blob: 31140d1259dcdd84e373c3affeee5e529de3af8b [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * raid5.c : Multiple Devices driver for Linux
3 * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman
4 * Copyright (C) 1999, 2000 Ingo Molnar
NeilBrown16a53ec2006-06-26 00:27:38 -07005 * Copyright (C) 2002, 2003 H. Peter Anvin
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 *
NeilBrown16a53ec2006-06-26 00:27:38 -07007 * RAID-4/5/6 management functions.
8 * Thanks to Penguin Computing for making the RAID-6 development possible
9 * by donating a test server!
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2, or (at your option)
14 * any later version.
15 *
16 * You should have received a copy of the GNU General Public License
17 * (for example /usr/src/linux/COPYING); if not, write to the Free
18 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20
NeilBrownae3c20c2006-07-10 04:44:17 -070021/*
22 * BITMAP UNPLUGGING:
23 *
24 * The sequencing for updating the bitmap reliably is a little
25 * subtle (and I got it wrong the first time) so it deserves some
26 * explanation.
27 *
28 * We group bitmap updates into batches. Each batch has a number.
29 * We may write out several batches at once, but that isn't very important.
30 * conf->bm_write is the number of the last batch successfully written.
31 * conf->bm_flush is the number of the last batch that was closed to
32 * new additions.
33 * When we discover that we will need to write to any block in a stripe
34 * (in add_stripe_bio) we update the in-memory bitmap and record in sh->bm_seq
35 * the number of the batch it will be in. This is bm_flush+1.
36 * When we are ready to do a write, if that batch hasn't been written yet,
37 * we plug the array and queue the stripe for later.
38 * When an unplug happens, we increment bm_flush, thus closing the current
39 * batch.
40 * When we notice that bm_flush > bm_write, we write out all pending updates
41 * to the bitmap, and advance bm_write to where bm_flush was.
42 * This may occasionally write a bit out twice, but is sure never to
43 * miss any bits.
44 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
NeilBrownbff61972009-03-31 14:33:13 +110046#include <linux/blkdev.h>
NeilBrownf6705572006-03-27 01:18:11 -080047#include <linux/kthread.h>
Dan Williamsf701d582009-03-31 15:09:39 +110048#include <linux/raid/pq.h>
Dan Williams91c00922007-01-02 13:52:30 -070049#include <linux/async_tx.h>
Dan Williams07a3b412009-08-29 19:13:13 -070050#include <linux/async.h>
NeilBrownbff61972009-03-31 14:33:13 +110051#include <linux/seq_file.h>
Dan Williams36d1c642009-07-14 11:48:22 -070052#include <linux/cpu.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090053#include <linux/slab.h>
NeilBrown43b2e5d2009-03-31 14:33:13 +110054#include "md.h"
NeilBrownbff61972009-03-31 14:33:13 +110055#include "raid5.h"
Trela Maciej54071b32010-03-08 16:02:42 +110056#include "raid0.h"
Christoph Hellwigef740c32009-03-31 14:27:03 +110057#include "bitmap.h"
NeilBrown72626682005-09-09 16:23:54 -070058
Linus Torvalds1da177e2005-04-16 15:20:36 -070059/*
60 * Stripe cache
61 */
62
63#define NR_STRIPES 256
64#define STRIPE_SIZE PAGE_SIZE
65#define STRIPE_SHIFT (PAGE_SHIFT - 9)
66#define STRIPE_SECTORS (STRIPE_SIZE>>9)
67#define IO_THRESHOLD 1
Dan Williams8b3e6cd2008-04-28 02:15:53 -070068#define BYPASS_THRESHOLD 1
NeilBrownfccddba2006-01-06 00:20:33 -080069#define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head))
Linus Torvalds1da177e2005-04-16 15:20:36 -070070#define HASH_MASK (NR_HASH - 1)
71
NeilBrownfccddba2006-01-06 00:20:33 -080072#define stripe_hash(conf, sect) (&((conf)->stripe_hashtbl[((sect) >> STRIPE_SHIFT) & HASH_MASK]))
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74/* bio's attached to a stripe+device for I/O are linked together in bi_sector
75 * order without overlap. There may be several bio's per stripe+device, and
76 * a bio could span several devices.
77 * When walking this list for a particular stripe+device, we must never proceed
78 * beyond a bio that extends past this device, as the next bio might no longer
79 * be valid.
80 * This macro is used to determine the 'next' bio in the list, given the sector
81 * of the current stripe+device
82 */
83#define r5_next_bio(bio, sect) ( ( (bio)->bi_sector + ((bio)->bi_size>>9) < sect + STRIPE_SECTORS) ? (bio)->bi_next : NULL)
84/*
85 * The following can be used to debug the driver
86 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070087#define RAID5_PARANOIA 1
88#if RAID5_PARANOIA && defined(CONFIG_SMP)
89# define CHECK_DEVLOCK() assert_spin_locked(&conf->device_lock)
90#else
91# define CHECK_DEVLOCK()
92#endif
93
Dan Williams45b42332007-07-09 11:56:43 -070094#ifdef DEBUG
Linus Torvalds1da177e2005-04-16 15:20:36 -070095#define inline
96#define __inline__
97#endif
98
Bernd Schubert6be9d492008-05-23 13:04:34 -070099#define printk_rl(args...) ((void) (printk_ratelimit() && printk(args)))
100
Jens Axboe960e7392008-08-15 10:41:18 +0200101/*
Jens Axboe5b99c2f2008-08-15 10:56:11 +0200102 * We maintain a biased count of active stripes in the bottom 16 bits of
103 * bi_phys_segments, and a count of processed stripes in the upper 16 bits
Jens Axboe960e7392008-08-15 10:41:18 +0200104 */
105static inline int raid5_bi_phys_segments(struct bio *bio)
106{
Jens Axboe5b99c2f2008-08-15 10:56:11 +0200107 return bio->bi_phys_segments & 0xffff;
Jens Axboe960e7392008-08-15 10:41:18 +0200108}
109
110static inline int raid5_bi_hw_segments(struct bio *bio)
111{
Jens Axboe5b99c2f2008-08-15 10:56:11 +0200112 return (bio->bi_phys_segments >> 16) & 0xffff;
Jens Axboe960e7392008-08-15 10:41:18 +0200113}
114
115static inline int raid5_dec_bi_phys_segments(struct bio *bio)
116{
117 --bio->bi_phys_segments;
118 return raid5_bi_phys_segments(bio);
119}
120
121static inline int raid5_dec_bi_hw_segments(struct bio *bio)
122{
123 unsigned short val = raid5_bi_hw_segments(bio);
124
125 --val;
Jens Axboe5b99c2f2008-08-15 10:56:11 +0200126 bio->bi_phys_segments = (val << 16) | raid5_bi_phys_segments(bio);
Jens Axboe960e7392008-08-15 10:41:18 +0200127 return val;
128}
129
130static inline void raid5_set_bi_hw_segments(struct bio *bio, unsigned int cnt)
131{
Jens Axboe5b99c2f2008-08-15 10:56:11 +0200132 bio->bi_phys_segments = raid5_bi_phys_segments(bio) || (cnt << 16);
Jens Axboe960e7392008-08-15 10:41:18 +0200133}
134
NeilBrownd0dabf72009-03-31 14:39:38 +1100135/* Find first data disk in a raid6 stripe */
136static inline int raid6_d0(struct stripe_head *sh)
137{
NeilBrown67cc2b82009-03-31 14:39:38 +1100138 if (sh->ddf_layout)
139 /* ddf always start from first device */
140 return 0;
141 /* md starts just after Q block */
NeilBrownd0dabf72009-03-31 14:39:38 +1100142 if (sh->qd_idx == sh->disks - 1)
143 return 0;
144 else
145 return sh->qd_idx + 1;
146}
NeilBrown16a53ec2006-06-26 00:27:38 -0700147static inline int raid6_next_disk(int disk, int raid_disks)
148{
149 disk++;
150 return (disk < raid_disks) ? disk : 0;
151}
Dan Williamsa4456852007-07-09 11:56:43 -0700152
NeilBrownd0dabf72009-03-31 14:39:38 +1100153/* When walking through the disks in a raid5, starting at raid6_d0,
154 * We need to map each disk to a 'slot', where the data disks are slot
155 * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk
156 * is raid_disks-1. This help does that mapping.
157 */
NeilBrown67cc2b82009-03-31 14:39:38 +1100158static int raid6_idx_to_slot(int idx, struct stripe_head *sh,
159 int *count, int syndrome_disks)
NeilBrownd0dabf72009-03-31 14:39:38 +1100160{
Dan Williams66295422009-10-19 18:09:32 -0700161 int slot = *count;
NeilBrown67cc2b82009-03-31 14:39:38 +1100162
NeilBrowne4424fe2009-10-16 16:27:34 +1100163 if (sh->ddf_layout)
Dan Williams66295422009-10-19 18:09:32 -0700164 (*count)++;
NeilBrownd0dabf72009-03-31 14:39:38 +1100165 if (idx == sh->pd_idx)
NeilBrown67cc2b82009-03-31 14:39:38 +1100166 return syndrome_disks;
NeilBrownd0dabf72009-03-31 14:39:38 +1100167 if (idx == sh->qd_idx)
NeilBrown67cc2b82009-03-31 14:39:38 +1100168 return syndrome_disks + 1;
NeilBrowne4424fe2009-10-16 16:27:34 +1100169 if (!sh->ddf_layout)
Dan Williams66295422009-10-19 18:09:32 -0700170 (*count)++;
NeilBrownd0dabf72009-03-31 14:39:38 +1100171 return slot;
172}
173
Dan Williamsa4456852007-07-09 11:56:43 -0700174static void return_io(struct bio *return_bi)
175{
176 struct bio *bi = return_bi;
177 while (bi) {
Dan Williamsa4456852007-07-09 11:56:43 -0700178
179 return_bi = bi->bi_next;
180 bi->bi_next = NULL;
181 bi->bi_size = 0;
Neil Brown0e13fe232008-06-28 08:31:20 +1000182 bio_endio(bi, 0);
Dan Williamsa4456852007-07-09 11:56:43 -0700183 bi = return_bi;
184 }
185}
186
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187static void print_raid5_conf (raid5_conf_t *conf);
188
Dan Williams600aa102008-06-28 08:32:05 +1000189static int stripe_operations_active(struct stripe_head *sh)
190{
191 return sh->check_state || sh->reconstruct_state ||
192 test_bit(STRIPE_BIOFILL_RUN, &sh->state) ||
193 test_bit(STRIPE_COMPUTE_RUN, &sh->state);
194}
195
Arjan van de Ven858119e2006-01-14 13:20:43 -0800196static void __release_stripe(raid5_conf_t *conf, struct stripe_head *sh)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197{
198 if (atomic_dec_and_test(&sh->count)) {
Eric Sesterhenn78bafeb2006-04-02 13:31:42 +0200199 BUG_ON(!list_empty(&sh->lru));
200 BUG_ON(atomic_read(&conf->active_stripes)==0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 if (test_bit(STRIPE_HANDLE, &sh->state)) {
NeilBrown7c785b72006-07-10 04:44:16 -0700202 if (test_bit(STRIPE_DELAYED, &sh->state)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 list_add_tail(&sh->lru, &conf->delayed_list);
NeilBrown2ac87402010-06-01 19:37:29 +1000204 plugger_set_plug(&conf->plug);
NeilBrown7c785b72006-07-10 04:44:16 -0700205 } else if (test_bit(STRIPE_BIT_DELAY, &sh->state) &&
NeilBrownae3c20c2006-07-10 04:44:17 -0700206 sh->bm_seq - conf->seq_write > 0) {
NeilBrown72626682005-09-09 16:23:54 -0700207 list_add_tail(&sh->lru, &conf->bitmap_list);
NeilBrown2ac87402010-06-01 19:37:29 +1000208 plugger_set_plug(&conf->plug);
NeilBrown7c785b72006-07-10 04:44:16 -0700209 } else {
NeilBrown72626682005-09-09 16:23:54 -0700210 clear_bit(STRIPE_BIT_DELAY, &sh->state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 list_add_tail(&sh->lru, &conf->handle_list);
NeilBrown72626682005-09-09 16:23:54 -0700212 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213 md_wakeup_thread(conf->mddev->thread);
214 } else {
Dan Williams600aa102008-06-28 08:32:05 +1000215 BUG_ON(stripe_operations_active(sh));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
217 atomic_dec(&conf->preread_active_stripes);
218 if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD)
219 md_wakeup_thread(conf->mddev->thread);
220 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 atomic_dec(&conf->active_stripes);
NeilBrownccfcc3c2006-03-27 01:18:09 -0800222 if (!test_bit(STRIPE_EXPANDING, &sh->state)) {
223 list_add_tail(&sh->lru, &conf->inactive_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 wake_up(&conf->wait_for_stripe);
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -0800225 if (conf->retry_read_aligned)
226 md_wakeup_thread(conf->mddev->thread);
NeilBrownccfcc3c2006-03-27 01:18:09 -0800227 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 }
229 }
230}
NeilBrownd0dabf72009-03-31 14:39:38 +1100231
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232static void release_stripe(struct stripe_head *sh)
233{
234 raid5_conf_t *conf = sh->raid_conf;
235 unsigned long flags;
NeilBrown16a53ec2006-06-26 00:27:38 -0700236
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 spin_lock_irqsave(&conf->device_lock, flags);
238 __release_stripe(conf, sh);
239 spin_unlock_irqrestore(&conf->device_lock, flags);
240}
241
NeilBrownfccddba2006-01-06 00:20:33 -0800242static inline void remove_hash(struct stripe_head *sh)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243{
Dan Williams45b42332007-07-09 11:56:43 -0700244 pr_debug("remove_hash(), stripe %llu\n",
245 (unsigned long long)sh->sector);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246
NeilBrownfccddba2006-01-06 00:20:33 -0800247 hlist_del_init(&sh->hash);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248}
249
NeilBrown16a53ec2006-06-26 00:27:38 -0700250static inline void insert_hash(raid5_conf_t *conf, struct stripe_head *sh)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251{
NeilBrownfccddba2006-01-06 00:20:33 -0800252 struct hlist_head *hp = stripe_hash(conf, sh->sector);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
Dan Williams45b42332007-07-09 11:56:43 -0700254 pr_debug("insert_hash(), stripe %llu\n",
255 (unsigned long long)sh->sector);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256
257 CHECK_DEVLOCK();
NeilBrownfccddba2006-01-06 00:20:33 -0800258 hlist_add_head(&sh->hash, hp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259}
260
261
262/* find an idle stripe, make sure it is unhashed, and return it. */
263static struct stripe_head *get_free_stripe(raid5_conf_t *conf)
264{
265 struct stripe_head *sh = NULL;
266 struct list_head *first;
267
268 CHECK_DEVLOCK();
269 if (list_empty(&conf->inactive_list))
270 goto out;
271 first = conf->inactive_list.next;
272 sh = list_entry(first, struct stripe_head, lru);
273 list_del_init(first);
274 remove_hash(sh);
275 atomic_inc(&conf->active_stripes);
276out:
277 return sh;
278}
279
NeilBrowne4e11e32010-06-16 16:45:16 +1000280static void shrink_buffers(struct stripe_head *sh)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281{
282 struct page *p;
283 int i;
NeilBrowne4e11e32010-06-16 16:45:16 +1000284 int num = sh->raid_conf->pool_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285
NeilBrowne4e11e32010-06-16 16:45:16 +1000286 for (i = 0; i < num ; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 p = sh->dev[i].page;
288 if (!p)
289 continue;
290 sh->dev[i].page = NULL;
NeilBrown2d1f3b52006-01-06 00:20:31 -0800291 put_page(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 }
293}
294
NeilBrowne4e11e32010-06-16 16:45:16 +1000295static int grow_buffers(struct stripe_head *sh)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296{
297 int i;
NeilBrowne4e11e32010-06-16 16:45:16 +1000298 int num = sh->raid_conf->pool_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299
NeilBrowne4e11e32010-06-16 16:45:16 +1000300 for (i = 0; i < num; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 struct page *page;
302
303 if (!(page = alloc_page(GFP_KERNEL))) {
304 return 1;
305 }
306 sh->dev[i].page = page;
307 }
308 return 0;
309}
310
NeilBrown784052e2009-03-31 15:19:07 +1100311static void raid5_build_block(struct stripe_head *sh, int i, int previous);
NeilBrown911d4ee2009-03-31 14:39:38 +1100312static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous,
313 struct stripe_head *sh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314
NeilBrownb5663ba2009-03-31 14:39:38 +1100315static void init_stripe(struct stripe_head *sh, sector_t sector, int previous)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316{
317 raid5_conf_t *conf = sh->raid_conf;
NeilBrown7ecaa1e2006-03-27 01:18:08 -0800318 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319
Eric Sesterhenn78bafeb2006-04-02 13:31:42 +0200320 BUG_ON(atomic_read(&sh->count) != 0);
321 BUG_ON(test_bit(STRIPE_HANDLE, &sh->state));
Dan Williams600aa102008-06-28 08:32:05 +1000322 BUG_ON(stripe_operations_active(sh));
Dan Williamsd84e0f12007-01-02 13:52:30 -0700323
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 CHECK_DEVLOCK();
Dan Williams45b42332007-07-09 11:56:43 -0700325 pr_debug("init_stripe called, stripe %llu\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 (unsigned long long)sh->sector);
327
328 remove_hash(sh);
NeilBrown16a53ec2006-06-26 00:27:38 -0700329
NeilBrown86b42c72009-03-31 15:19:03 +1100330 sh->generation = conf->generation - previous;
NeilBrownb5663ba2009-03-31 14:39:38 +1100331 sh->disks = previous ? conf->previous_raid_disks : conf->raid_disks;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 sh->sector = sector;
NeilBrown911d4ee2009-03-31 14:39:38 +1100333 stripe_set_idx(sector, conf, previous, sh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 sh->state = 0;
335
NeilBrown7ecaa1e2006-03-27 01:18:08 -0800336
337 for (i = sh->disks; i--; ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 struct r5dev *dev = &sh->dev[i];
339
Dan Williamsd84e0f12007-01-02 13:52:30 -0700340 if (dev->toread || dev->read || dev->towrite || dev->written ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 test_bit(R5_LOCKED, &dev->flags)) {
Dan Williamsd84e0f12007-01-02 13:52:30 -0700342 printk(KERN_ERR "sector=%llx i=%d %p %p %p %p %d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 (unsigned long long)sh->sector, i, dev->toread,
Dan Williamsd84e0f12007-01-02 13:52:30 -0700344 dev->read, dev->towrite, dev->written,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 test_bit(R5_LOCKED, &dev->flags));
346 BUG();
347 }
348 dev->flags = 0;
NeilBrown784052e2009-03-31 15:19:07 +1100349 raid5_build_block(sh, i, previous);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 }
351 insert_hash(conf, sh);
352}
353
NeilBrown86b42c72009-03-31 15:19:03 +1100354static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector,
355 short generation)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356{
357 struct stripe_head *sh;
NeilBrownfccddba2006-01-06 00:20:33 -0800358 struct hlist_node *hn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359
360 CHECK_DEVLOCK();
Dan Williams45b42332007-07-09 11:56:43 -0700361 pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector);
NeilBrownfccddba2006-01-06 00:20:33 -0800362 hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash)
NeilBrown86b42c72009-03-31 15:19:03 +1100363 if (sh->sector == sector && sh->generation == generation)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 return sh;
Dan Williams45b42332007-07-09 11:56:43 -0700365 pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 return NULL;
367}
368
NeilBrown674806d2010-06-16 17:17:53 +1000369/*
370 * Need to check if array has failed when deciding whether to:
371 * - start an array
372 * - remove non-faulty devices
373 * - add a spare
374 * - allow a reshape
375 * This determination is simple when no reshape is happening.
376 * However if there is a reshape, we need to carefully check
377 * both the before and after sections.
378 * This is because some failed devices may only affect one
379 * of the two sections, and some non-in_sync devices may
380 * be insync in the section most affected by failed devices.
381 */
382static int has_failed(raid5_conf_t *conf)
383{
384 int degraded;
385 int i;
386 if (conf->mddev->reshape_position == MaxSector)
387 return conf->mddev->degraded > conf->max_degraded;
388
389 rcu_read_lock();
390 degraded = 0;
391 for (i = 0; i < conf->previous_raid_disks; i++) {
392 mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev);
393 if (!rdev || test_bit(Faulty, &rdev->flags))
394 degraded++;
395 else if (test_bit(In_sync, &rdev->flags))
396 ;
397 else
398 /* not in-sync or faulty.
399 * If the reshape increases the number of devices,
400 * this is being recovered by the reshape, so
401 * this 'previous' section is not in_sync.
402 * If the number of devices is being reduced however,
403 * the device can only be part of the array if
404 * we are reverting a reshape, so this section will
405 * be in-sync.
406 */
407 if (conf->raid_disks >= conf->previous_raid_disks)
408 degraded++;
409 }
410 rcu_read_unlock();
411 if (degraded > conf->max_degraded)
412 return 1;
413 rcu_read_lock();
414 degraded = 0;
415 for (i = 0; i < conf->raid_disks; i++) {
416 mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev);
417 if (!rdev || test_bit(Faulty, &rdev->flags))
418 degraded++;
419 else if (test_bit(In_sync, &rdev->flags))
420 ;
421 else
422 /* not in-sync or faulty.
423 * If reshape increases the number of devices, this
424 * section has already been recovered, else it
425 * almost certainly hasn't.
426 */
427 if (conf->raid_disks <= conf->previous_raid_disks)
428 degraded++;
429 }
430 rcu_read_unlock();
431 if (degraded > conf->max_degraded)
432 return 1;
433 return 0;
434}
435
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436static void unplug_slaves(mddev_t *mddev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
NeilBrownb5663ba2009-03-31 14:39:38 +1100438static struct stripe_head *
439get_active_stripe(raid5_conf_t *conf, sector_t sector,
NeilBrowna8c906c2009-06-09 14:39:59 +1000440 int previous, int noblock, int noquiesce)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441{
442 struct stripe_head *sh;
443
Dan Williams45b42332007-07-09 11:56:43 -0700444 pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445
446 spin_lock_irq(&conf->device_lock);
447
448 do {
NeilBrown72626682005-09-09 16:23:54 -0700449 wait_event_lock_irq(conf->wait_for_stripe,
NeilBrowna8c906c2009-06-09 14:39:59 +1000450 conf->quiesce == 0 || noquiesce,
NeilBrown72626682005-09-09 16:23:54 -0700451 conf->device_lock, /* nothing */);
NeilBrown86b42c72009-03-31 15:19:03 +1100452 sh = __find_stripe(conf, sector, conf->generation - previous);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 if (!sh) {
454 if (!conf->inactive_blocked)
455 sh = get_free_stripe(conf);
456 if (noblock && sh == NULL)
457 break;
458 if (!sh) {
459 conf->inactive_blocked = 1;
460 wait_event_lock_irq(conf->wait_for_stripe,
461 !list_empty(&conf->inactive_list) &&
NeilBrown50368052005-12-12 02:39:17 -0800462 (atomic_read(&conf->active_stripes)
463 < (conf->max_nr_stripes *3/4)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464 || !conf->inactive_blocked),
465 conf->device_lock,
NeilBrown9f7c2222010-07-26 12:04:13 +1000466 md_raid5_unplug_device(conf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 );
468 conf->inactive_blocked = 0;
469 } else
NeilBrownb5663ba2009-03-31 14:39:38 +1100470 init_stripe(sh, sector, previous);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471 } else {
472 if (atomic_read(&sh->count)) {
NeilBrownab69ae12009-03-31 15:26:47 +1100473 BUG_ON(!list_empty(&sh->lru)
474 && !test_bit(STRIPE_EXPANDING, &sh->state));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 } else {
476 if (!test_bit(STRIPE_HANDLE, &sh->state))
477 atomic_inc(&conf->active_stripes);
NeilBrownff4e8d92006-07-10 04:44:16 -0700478 if (list_empty(&sh->lru) &&
479 !test_bit(STRIPE_EXPANDING, &sh->state))
NeilBrown16a53ec2006-06-26 00:27:38 -0700480 BUG();
481 list_del_init(&sh->lru);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 }
483 }
484 } while (sh == NULL);
485
486 if (sh)
487 atomic_inc(&sh->count);
488
489 spin_unlock_irq(&conf->device_lock);
490 return sh;
491}
492
NeilBrown6712ecf2007-09-27 12:47:43 +0200493static void
494raid5_end_read_request(struct bio *bi, int error);
495static void
496raid5_end_write_request(struct bio *bi, int error);
Dan Williams91c00922007-01-02 13:52:30 -0700497
Dan Williamsc4e5ac02008-06-28 08:31:53 +1000498static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
Dan Williams91c00922007-01-02 13:52:30 -0700499{
500 raid5_conf_t *conf = sh->raid_conf;
501 int i, disks = sh->disks;
502
503 might_sleep();
504
505 for (i = disks; i--; ) {
506 int rw;
507 struct bio *bi;
508 mdk_rdev_t *rdev;
Tejun Heoe9c74692010-09-03 11:56:18 +0200509 if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) {
510 if (test_and_clear_bit(R5_WantFUA, &sh->dev[i].flags))
511 rw = WRITE_FUA;
512 else
513 rw = WRITE;
514 } else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags))
Dan Williams91c00922007-01-02 13:52:30 -0700515 rw = READ;
516 else
517 continue;
518
519 bi = &sh->dev[i].req;
520
521 bi->bi_rw = rw;
522 if (rw == WRITE)
523 bi->bi_end_io = raid5_end_write_request;
524 else
525 bi->bi_end_io = raid5_end_read_request;
526
527 rcu_read_lock();
528 rdev = rcu_dereference(conf->disks[i].rdev);
529 if (rdev && test_bit(Faulty, &rdev->flags))
530 rdev = NULL;
531 if (rdev)
532 atomic_inc(&rdev->nr_pending);
533 rcu_read_unlock();
534
535 if (rdev) {
Dan Williamsc4e5ac02008-06-28 08:31:53 +1000536 if (s->syncing || s->expanding || s->expanded)
Dan Williams91c00922007-01-02 13:52:30 -0700537 md_sync_acct(rdev->bdev, STRIPE_SECTORS);
538
Dan Williams2b7497f2008-06-28 08:31:52 +1000539 set_bit(STRIPE_IO_STARTED, &sh->state);
540
Dan Williams91c00922007-01-02 13:52:30 -0700541 bi->bi_bdev = rdev->bdev;
542 pr_debug("%s: for %llu schedule op %ld on disc %d\n",
Harvey Harrisone46b2722008-04-28 02:15:50 -0700543 __func__, (unsigned long long)sh->sector,
Dan Williams91c00922007-01-02 13:52:30 -0700544 bi->bi_rw, i);
545 atomic_inc(&sh->count);
546 bi->bi_sector = sh->sector + rdev->data_offset;
547 bi->bi_flags = 1 << BIO_UPTODATE;
548 bi->bi_vcnt = 1;
549 bi->bi_max_vecs = 1;
550 bi->bi_idx = 0;
551 bi->bi_io_vec = &sh->dev[i].vec;
552 bi->bi_io_vec[0].bv_len = STRIPE_SIZE;
553 bi->bi_io_vec[0].bv_offset = 0;
554 bi->bi_size = STRIPE_SIZE;
555 bi->bi_next = NULL;
556 if (rw == WRITE &&
557 test_bit(R5_ReWrite, &sh->dev[i].flags))
558 atomic_add(STRIPE_SECTORS,
559 &rdev->corrected_errors);
560 generic_make_request(bi);
561 } else {
562 if (rw == WRITE)
563 set_bit(STRIPE_DEGRADED, &sh->state);
564 pr_debug("skip op %ld on disc %d for sector %llu\n",
565 bi->bi_rw, i, (unsigned long long)sh->sector);
566 clear_bit(R5_LOCKED, &sh->dev[i].flags);
567 set_bit(STRIPE_HANDLE, &sh->state);
568 }
569 }
570}
571
572static struct dma_async_tx_descriptor *
573async_copy_data(int frombio, struct bio *bio, struct page *page,
574 sector_t sector, struct dma_async_tx_descriptor *tx)
575{
576 struct bio_vec *bvl;
577 struct page *bio_page;
578 int i;
579 int page_offset;
Dan Williamsa08abd82009-06-03 11:43:59 -0700580 struct async_submit_ctl submit;
Dan Williams0403e382009-09-08 17:42:50 -0700581 enum async_tx_flags flags = 0;
Dan Williams91c00922007-01-02 13:52:30 -0700582
583 if (bio->bi_sector >= sector)
584 page_offset = (signed)(bio->bi_sector - sector) * 512;
585 else
586 page_offset = (signed)(sector - bio->bi_sector) * -512;
Dan Williamsa08abd82009-06-03 11:43:59 -0700587
Dan Williams0403e382009-09-08 17:42:50 -0700588 if (frombio)
589 flags |= ASYNC_TX_FENCE;
590 init_async_submit(&submit, flags, tx, NULL, NULL, NULL);
591
Dan Williams91c00922007-01-02 13:52:30 -0700592 bio_for_each_segment(bvl, bio, i) {
593 int len = bio_iovec_idx(bio, i)->bv_len;
594 int clen;
595 int b_offset = 0;
596
597 if (page_offset < 0) {
598 b_offset = -page_offset;
599 page_offset += b_offset;
600 len -= b_offset;
601 }
602
603 if (len > 0 && page_offset + len > STRIPE_SIZE)
604 clen = STRIPE_SIZE - page_offset;
605 else
606 clen = len;
607
608 if (clen > 0) {
609 b_offset += bio_iovec_idx(bio, i)->bv_offset;
610 bio_page = bio_iovec_idx(bio, i)->bv_page;
611 if (frombio)
612 tx = async_memcpy(page, bio_page, page_offset,
Dan Williamsa08abd82009-06-03 11:43:59 -0700613 b_offset, clen, &submit);
Dan Williams91c00922007-01-02 13:52:30 -0700614 else
615 tx = async_memcpy(bio_page, page, b_offset,
Dan Williamsa08abd82009-06-03 11:43:59 -0700616 page_offset, clen, &submit);
Dan Williams91c00922007-01-02 13:52:30 -0700617 }
Dan Williamsa08abd82009-06-03 11:43:59 -0700618 /* chain the operations */
619 submit.depend_tx = tx;
620
Dan Williams91c00922007-01-02 13:52:30 -0700621 if (clen < len) /* hit end of page */
622 break;
623 page_offset += len;
624 }
625
626 return tx;
627}
628
629static void ops_complete_biofill(void *stripe_head_ref)
630{
631 struct stripe_head *sh = stripe_head_ref;
632 struct bio *return_bi = NULL;
633 raid5_conf_t *conf = sh->raid_conf;
Dan Williamse4d84902007-09-24 10:06:13 -0700634 int i;
Dan Williams91c00922007-01-02 13:52:30 -0700635
Harvey Harrisone46b2722008-04-28 02:15:50 -0700636 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -0700637 (unsigned long long)sh->sector);
638
639 /* clear completed biofills */
Dan Williams83de75c2008-06-28 08:31:58 +1000640 spin_lock_irq(&conf->device_lock);
Dan Williams91c00922007-01-02 13:52:30 -0700641 for (i = sh->disks; i--; ) {
642 struct r5dev *dev = &sh->dev[i];
Dan Williams91c00922007-01-02 13:52:30 -0700643
644 /* acknowledge completion of a biofill operation */
Dan Williamse4d84902007-09-24 10:06:13 -0700645 /* and check if we need to reply to a read request,
646 * new R5_Wantfill requests are held off until
Dan Williams83de75c2008-06-28 08:31:58 +1000647 * !STRIPE_BIOFILL_RUN
Dan Williamse4d84902007-09-24 10:06:13 -0700648 */
649 if (test_and_clear_bit(R5_Wantfill, &dev->flags)) {
Dan Williams91c00922007-01-02 13:52:30 -0700650 struct bio *rbi, *rbi2;
Dan Williams91c00922007-01-02 13:52:30 -0700651
Dan Williams91c00922007-01-02 13:52:30 -0700652 BUG_ON(!dev->read);
653 rbi = dev->read;
654 dev->read = NULL;
655 while (rbi && rbi->bi_sector <
656 dev->sector + STRIPE_SECTORS) {
657 rbi2 = r5_next_bio(rbi, dev->sector);
Jens Axboe960e7392008-08-15 10:41:18 +0200658 if (!raid5_dec_bi_phys_segments(rbi)) {
Dan Williams91c00922007-01-02 13:52:30 -0700659 rbi->bi_next = return_bi;
660 return_bi = rbi;
661 }
Dan Williams91c00922007-01-02 13:52:30 -0700662 rbi = rbi2;
663 }
664 }
665 }
Dan Williams83de75c2008-06-28 08:31:58 +1000666 spin_unlock_irq(&conf->device_lock);
667 clear_bit(STRIPE_BIOFILL_RUN, &sh->state);
Dan Williams91c00922007-01-02 13:52:30 -0700668
669 return_io(return_bi);
670
Dan Williamse4d84902007-09-24 10:06:13 -0700671 set_bit(STRIPE_HANDLE, &sh->state);
Dan Williams91c00922007-01-02 13:52:30 -0700672 release_stripe(sh);
673}
674
675static void ops_run_biofill(struct stripe_head *sh)
676{
677 struct dma_async_tx_descriptor *tx = NULL;
678 raid5_conf_t *conf = sh->raid_conf;
Dan Williamsa08abd82009-06-03 11:43:59 -0700679 struct async_submit_ctl submit;
Dan Williams91c00922007-01-02 13:52:30 -0700680 int i;
681
Harvey Harrisone46b2722008-04-28 02:15:50 -0700682 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -0700683 (unsigned long long)sh->sector);
684
685 for (i = sh->disks; i--; ) {
686 struct r5dev *dev = &sh->dev[i];
687 if (test_bit(R5_Wantfill, &dev->flags)) {
688 struct bio *rbi;
689 spin_lock_irq(&conf->device_lock);
690 dev->read = rbi = dev->toread;
691 dev->toread = NULL;
692 spin_unlock_irq(&conf->device_lock);
693 while (rbi && rbi->bi_sector <
694 dev->sector + STRIPE_SECTORS) {
695 tx = async_copy_data(0, rbi, dev->page,
696 dev->sector, tx);
697 rbi = r5_next_bio(rbi, dev->sector);
698 }
699 }
700 }
701
702 atomic_inc(&sh->count);
Dan Williamsa08abd82009-06-03 11:43:59 -0700703 init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_biofill, sh, NULL);
704 async_trigger_callback(&submit);
Dan Williams91c00922007-01-02 13:52:30 -0700705}
706
Dan Williams4e7d2c02009-08-29 19:13:11 -0700707static void mark_target_uptodate(struct stripe_head *sh, int target)
708{
709 struct r5dev *tgt;
710
711 if (target < 0)
712 return;
713
714 tgt = &sh->dev[target];
715 set_bit(R5_UPTODATE, &tgt->flags);
716 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
717 clear_bit(R5_Wantcompute, &tgt->flags);
718}
719
Dan Williamsac6b53b2009-07-14 13:40:19 -0700720static void ops_complete_compute(void *stripe_head_ref)
Dan Williams91c00922007-01-02 13:52:30 -0700721{
722 struct stripe_head *sh = stripe_head_ref;
Dan Williams91c00922007-01-02 13:52:30 -0700723
Harvey Harrisone46b2722008-04-28 02:15:50 -0700724 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -0700725 (unsigned long long)sh->sector);
726
Dan Williamsac6b53b2009-07-14 13:40:19 -0700727 /* mark the computed target(s) as uptodate */
Dan Williams4e7d2c02009-08-29 19:13:11 -0700728 mark_target_uptodate(sh, sh->ops.target);
Dan Williamsac6b53b2009-07-14 13:40:19 -0700729 mark_target_uptodate(sh, sh->ops.target2);
Dan Williams4e7d2c02009-08-29 19:13:11 -0700730
Dan Williamsecc65c92008-06-28 08:31:57 +1000731 clear_bit(STRIPE_COMPUTE_RUN, &sh->state);
732 if (sh->check_state == check_state_compute_run)
733 sh->check_state = check_state_compute_result;
Dan Williams91c00922007-01-02 13:52:30 -0700734 set_bit(STRIPE_HANDLE, &sh->state);
735 release_stripe(sh);
736}
737
Dan Williamsd6f38f32009-07-14 11:50:52 -0700738/* return a pointer to the address conversion region of the scribble buffer */
739static addr_conv_t *to_addr_conv(struct stripe_head *sh,
740 struct raid5_percpu *percpu)
Dan Williams91c00922007-01-02 13:52:30 -0700741{
Dan Williamsd6f38f32009-07-14 11:50:52 -0700742 return percpu->scribble + sizeof(struct page *) * (sh->disks + 2);
743}
744
745static struct dma_async_tx_descriptor *
746ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu)
747{
Dan Williams91c00922007-01-02 13:52:30 -0700748 int disks = sh->disks;
Dan Williamsd6f38f32009-07-14 11:50:52 -0700749 struct page **xor_srcs = percpu->scribble;
Dan Williams91c00922007-01-02 13:52:30 -0700750 int target = sh->ops.target;
751 struct r5dev *tgt = &sh->dev[target];
752 struct page *xor_dest = tgt->page;
753 int count = 0;
754 struct dma_async_tx_descriptor *tx;
Dan Williamsa08abd82009-06-03 11:43:59 -0700755 struct async_submit_ctl submit;
Dan Williams91c00922007-01-02 13:52:30 -0700756 int i;
757
758 pr_debug("%s: stripe %llu block: %d\n",
Harvey Harrisone46b2722008-04-28 02:15:50 -0700759 __func__, (unsigned long long)sh->sector, target);
Dan Williams91c00922007-01-02 13:52:30 -0700760 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
761
762 for (i = disks; i--; )
763 if (i != target)
764 xor_srcs[count++] = sh->dev[i].page;
765
766 atomic_inc(&sh->count);
767
Dan Williams0403e382009-09-08 17:42:50 -0700768 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, NULL,
Dan Williamsac6b53b2009-07-14 13:40:19 -0700769 ops_complete_compute, sh, to_addr_conv(sh, percpu));
Dan Williams91c00922007-01-02 13:52:30 -0700770 if (unlikely(count == 1))
Dan Williamsa08abd82009-06-03 11:43:59 -0700771 tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
Dan Williams91c00922007-01-02 13:52:30 -0700772 else
Dan Williamsa08abd82009-06-03 11:43:59 -0700773 tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
Dan Williams91c00922007-01-02 13:52:30 -0700774
Dan Williams91c00922007-01-02 13:52:30 -0700775 return tx;
776}
777
Dan Williamsac6b53b2009-07-14 13:40:19 -0700778/* set_syndrome_sources - populate source buffers for gen_syndrome
779 * @srcs - (struct page *) array of size sh->disks
780 * @sh - stripe_head to parse
781 *
782 * Populates srcs in proper layout order for the stripe and returns the
783 * 'count' of sources to be used in a call to async_gen_syndrome. The P
784 * destination buffer is recorded in srcs[count] and the Q destination
785 * is recorded in srcs[count+1]].
786 */
787static int set_syndrome_sources(struct page **srcs, struct stripe_head *sh)
788{
789 int disks = sh->disks;
790 int syndrome_disks = sh->ddf_layout ? disks : (disks - 2);
791 int d0_idx = raid6_d0(sh);
792 int count;
793 int i;
794
795 for (i = 0; i < disks; i++)
NeilBrown5dd33c92009-10-16 16:40:25 +1100796 srcs[i] = NULL;
Dan Williamsac6b53b2009-07-14 13:40:19 -0700797
798 count = 0;
799 i = d0_idx;
800 do {
801 int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
802
803 srcs[slot] = sh->dev[i].page;
804 i = raid6_next_disk(i, disks);
805 } while (i != d0_idx);
Dan Williamsac6b53b2009-07-14 13:40:19 -0700806
NeilBrowne4424fe2009-10-16 16:27:34 +1100807 return syndrome_disks;
Dan Williamsac6b53b2009-07-14 13:40:19 -0700808}
809
810static struct dma_async_tx_descriptor *
811ops_run_compute6_1(struct stripe_head *sh, struct raid5_percpu *percpu)
812{
813 int disks = sh->disks;
814 struct page **blocks = percpu->scribble;
815 int target;
816 int qd_idx = sh->qd_idx;
817 struct dma_async_tx_descriptor *tx;
818 struct async_submit_ctl submit;
819 struct r5dev *tgt;
820 struct page *dest;
821 int i;
822 int count;
823
824 if (sh->ops.target < 0)
825 target = sh->ops.target2;
826 else if (sh->ops.target2 < 0)
827 target = sh->ops.target;
828 else
829 /* we should only have one valid target */
830 BUG();
831 BUG_ON(target < 0);
832 pr_debug("%s: stripe %llu block: %d\n",
833 __func__, (unsigned long long)sh->sector, target);
834
835 tgt = &sh->dev[target];
836 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
837 dest = tgt->page;
838
839 atomic_inc(&sh->count);
840
841 if (target == qd_idx) {
842 count = set_syndrome_sources(blocks, sh);
843 blocks[count] = NULL; /* regenerating p is not necessary */
844 BUG_ON(blocks[count+1] != dest); /* q should already be set */
Dan Williams0403e382009-09-08 17:42:50 -0700845 init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
846 ops_complete_compute, sh,
Dan Williamsac6b53b2009-07-14 13:40:19 -0700847 to_addr_conv(sh, percpu));
848 tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
849 } else {
850 /* Compute any data- or p-drive using XOR */
851 count = 0;
852 for (i = disks; i-- ; ) {
853 if (i == target || i == qd_idx)
854 continue;
855 blocks[count++] = sh->dev[i].page;
856 }
857
Dan Williams0403e382009-09-08 17:42:50 -0700858 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST,
859 NULL, ops_complete_compute, sh,
Dan Williamsac6b53b2009-07-14 13:40:19 -0700860 to_addr_conv(sh, percpu));
861 tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE, &submit);
862 }
863
864 return tx;
865}
866
867static struct dma_async_tx_descriptor *
868ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu)
869{
870 int i, count, disks = sh->disks;
871 int syndrome_disks = sh->ddf_layout ? disks : disks-2;
872 int d0_idx = raid6_d0(sh);
873 int faila = -1, failb = -1;
874 int target = sh->ops.target;
875 int target2 = sh->ops.target2;
876 struct r5dev *tgt = &sh->dev[target];
877 struct r5dev *tgt2 = &sh->dev[target2];
878 struct dma_async_tx_descriptor *tx;
879 struct page **blocks = percpu->scribble;
880 struct async_submit_ctl submit;
881
882 pr_debug("%s: stripe %llu block1: %d block2: %d\n",
883 __func__, (unsigned long long)sh->sector, target, target2);
884 BUG_ON(target < 0 || target2 < 0);
885 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
886 BUG_ON(!test_bit(R5_Wantcompute, &tgt2->flags));
887
Dan Williams6c910a72009-09-16 12:24:54 -0700888 /* we need to open-code set_syndrome_sources to handle the
Dan Williamsac6b53b2009-07-14 13:40:19 -0700889 * slot number conversion for 'faila' and 'failb'
890 */
891 for (i = 0; i < disks ; i++)
NeilBrown5dd33c92009-10-16 16:40:25 +1100892 blocks[i] = NULL;
Dan Williamsac6b53b2009-07-14 13:40:19 -0700893 count = 0;
894 i = d0_idx;
895 do {
896 int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
897
898 blocks[slot] = sh->dev[i].page;
899
900 if (i == target)
901 faila = slot;
902 if (i == target2)
903 failb = slot;
904 i = raid6_next_disk(i, disks);
905 } while (i != d0_idx);
Dan Williamsac6b53b2009-07-14 13:40:19 -0700906
907 BUG_ON(faila == failb);
908 if (failb < faila)
909 swap(faila, failb);
910 pr_debug("%s: stripe: %llu faila: %d failb: %d\n",
911 __func__, (unsigned long long)sh->sector, faila, failb);
912
913 atomic_inc(&sh->count);
914
915 if (failb == syndrome_disks+1) {
916 /* Q disk is one of the missing disks */
917 if (faila == syndrome_disks) {
918 /* Missing P+Q, just recompute */
Dan Williams0403e382009-09-08 17:42:50 -0700919 init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
920 ops_complete_compute, sh,
921 to_addr_conv(sh, percpu));
NeilBrowne4424fe2009-10-16 16:27:34 +1100922 return async_gen_syndrome(blocks, 0, syndrome_disks+2,
Dan Williamsac6b53b2009-07-14 13:40:19 -0700923 STRIPE_SIZE, &submit);
924 } else {
925 struct page *dest;
926 int data_target;
927 int qd_idx = sh->qd_idx;
928
929 /* Missing D+Q: recompute D from P, then recompute Q */
930 if (target == qd_idx)
931 data_target = target2;
932 else
933 data_target = target;
934
935 count = 0;
936 for (i = disks; i-- ; ) {
937 if (i == data_target || i == qd_idx)
938 continue;
939 blocks[count++] = sh->dev[i].page;
940 }
941 dest = sh->dev[data_target].page;
Dan Williams0403e382009-09-08 17:42:50 -0700942 init_async_submit(&submit,
943 ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST,
944 NULL, NULL, NULL,
945 to_addr_conv(sh, percpu));
Dan Williamsac6b53b2009-07-14 13:40:19 -0700946 tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE,
947 &submit);
948
949 count = set_syndrome_sources(blocks, sh);
Dan Williams0403e382009-09-08 17:42:50 -0700950 init_async_submit(&submit, ASYNC_TX_FENCE, tx,
951 ops_complete_compute, sh,
952 to_addr_conv(sh, percpu));
Dan Williamsac6b53b2009-07-14 13:40:19 -0700953 return async_gen_syndrome(blocks, 0, count+2,
954 STRIPE_SIZE, &submit);
955 }
Dan Williamsac6b53b2009-07-14 13:40:19 -0700956 } else {
Dan Williams6c910a72009-09-16 12:24:54 -0700957 init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
958 ops_complete_compute, sh,
959 to_addr_conv(sh, percpu));
960 if (failb == syndrome_disks) {
961 /* We're missing D+P. */
962 return async_raid6_datap_recov(syndrome_disks+2,
963 STRIPE_SIZE, faila,
964 blocks, &submit);
965 } else {
966 /* We're missing D+D. */
967 return async_raid6_2data_recov(syndrome_disks+2,
968 STRIPE_SIZE, faila, failb,
969 blocks, &submit);
970 }
Dan Williamsac6b53b2009-07-14 13:40:19 -0700971 }
972}
973
974
Dan Williams91c00922007-01-02 13:52:30 -0700975static void ops_complete_prexor(void *stripe_head_ref)
976{
977 struct stripe_head *sh = stripe_head_ref;
978
Harvey Harrisone46b2722008-04-28 02:15:50 -0700979 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -0700980 (unsigned long long)sh->sector);
Dan Williams91c00922007-01-02 13:52:30 -0700981}
982
983static struct dma_async_tx_descriptor *
Dan Williamsd6f38f32009-07-14 11:50:52 -0700984ops_run_prexor(struct stripe_head *sh, struct raid5_percpu *percpu,
985 struct dma_async_tx_descriptor *tx)
Dan Williams91c00922007-01-02 13:52:30 -0700986{
Dan Williams91c00922007-01-02 13:52:30 -0700987 int disks = sh->disks;
Dan Williamsd6f38f32009-07-14 11:50:52 -0700988 struct page **xor_srcs = percpu->scribble;
Dan Williams91c00922007-01-02 13:52:30 -0700989 int count = 0, pd_idx = sh->pd_idx, i;
Dan Williamsa08abd82009-06-03 11:43:59 -0700990 struct async_submit_ctl submit;
Dan Williams91c00922007-01-02 13:52:30 -0700991
992 /* existing parity data subtracted */
993 struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page;
994
Harvey Harrisone46b2722008-04-28 02:15:50 -0700995 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -0700996 (unsigned long long)sh->sector);
997
998 for (i = disks; i--; ) {
999 struct r5dev *dev = &sh->dev[i];
1000 /* Only process blocks that are known to be uptodate */
Dan Williamsd8ee0722008-06-28 08:32:06 +10001001 if (test_bit(R5_Wantdrain, &dev->flags))
Dan Williams91c00922007-01-02 13:52:30 -07001002 xor_srcs[count++] = dev->page;
1003 }
1004
Dan Williams0403e382009-09-08 17:42:50 -07001005 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
Dan Williamsd6f38f32009-07-14 11:50:52 -07001006 ops_complete_prexor, sh, to_addr_conv(sh, percpu));
Dan Williamsa08abd82009-06-03 11:43:59 -07001007 tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
Dan Williams91c00922007-01-02 13:52:30 -07001008
1009 return tx;
1010}
1011
1012static struct dma_async_tx_descriptor *
Dan Williamsd8ee0722008-06-28 08:32:06 +10001013ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
Dan Williams91c00922007-01-02 13:52:30 -07001014{
1015 int disks = sh->disks;
Dan Williamsd8ee0722008-06-28 08:32:06 +10001016 int i;
Dan Williams91c00922007-01-02 13:52:30 -07001017
Harvey Harrisone46b2722008-04-28 02:15:50 -07001018 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -07001019 (unsigned long long)sh->sector);
1020
1021 for (i = disks; i--; ) {
1022 struct r5dev *dev = &sh->dev[i];
1023 struct bio *chosen;
Dan Williams91c00922007-01-02 13:52:30 -07001024
Dan Williamsd8ee0722008-06-28 08:32:06 +10001025 if (test_and_clear_bit(R5_Wantdrain, &dev->flags)) {
Dan Williams91c00922007-01-02 13:52:30 -07001026 struct bio *wbi;
1027
1028 spin_lock(&sh->lock);
1029 chosen = dev->towrite;
1030 dev->towrite = NULL;
1031 BUG_ON(dev->written);
1032 wbi = dev->written = chosen;
1033 spin_unlock(&sh->lock);
1034
1035 while (wbi && wbi->bi_sector <
1036 dev->sector + STRIPE_SECTORS) {
Tejun Heoe9c74692010-09-03 11:56:18 +02001037 if (wbi->bi_rw & REQ_FUA)
1038 set_bit(R5_WantFUA, &dev->flags);
Dan Williams91c00922007-01-02 13:52:30 -07001039 tx = async_copy_data(1, wbi, dev->page,
1040 dev->sector, tx);
1041 wbi = r5_next_bio(wbi, dev->sector);
1042 }
1043 }
1044 }
1045
1046 return tx;
1047}
1048
Dan Williamsac6b53b2009-07-14 13:40:19 -07001049static void ops_complete_reconstruct(void *stripe_head_ref)
Dan Williams91c00922007-01-02 13:52:30 -07001050{
1051 struct stripe_head *sh = stripe_head_ref;
Dan Williamsac6b53b2009-07-14 13:40:19 -07001052 int disks = sh->disks;
1053 int pd_idx = sh->pd_idx;
1054 int qd_idx = sh->qd_idx;
1055 int i;
Tejun Heoe9c74692010-09-03 11:56:18 +02001056 bool fua = false;
Dan Williams91c00922007-01-02 13:52:30 -07001057
Harvey Harrisone46b2722008-04-28 02:15:50 -07001058 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -07001059 (unsigned long long)sh->sector);
1060
Tejun Heoe9c74692010-09-03 11:56:18 +02001061 for (i = disks; i--; )
1062 fua |= test_bit(R5_WantFUA, &sh->dev[i].flags);
1063
Dan Williams91c00922007-01-02 13:52:30 -07001064 for (i = disks; i--; ) {
1065 struct r5dev *dev = &sh->dev[i];
Dan Williamsac6b53b2009-07-14 13:40:19 -07001066
Tejun Heoe9c74692010-09-03 11:56:18 +02001067 if (dev->written || i == pd_idx || i == qd_idx) {
Dan Williams91c00922007-01-02 13:52:30 -07001068 set_bit(R5_UPTODATE, &dev->flags);
Tejun Heoe9c74692010-09-03 11:56:18 +02001069 if (fua)
1070 set_bit(R5_WantFUA, &dev->flags);
1071 }
Dan Williams91c00922007-01-02 13:52:30 -07001072 }
1073
Dan Williamsd8ee0722008-06-28 08:32:06 +10001074 if (sh->reconstruct_state == reconstruct_state_drain_run)
1075 sh->reconstruct_state = reconstruct_state_drain_result;
1076 else if (sh->reconstruct_state == reconstruct_state_prexor_drain_run)
1077 sh->reconstruct_state = reconstruct_state_prexor_drain_result;
1078 else {
1079 BUG_ON(sh->reconstruct_state != reconstruct_state_run);
1080 sh->reconstruct_state = reconstruct_state_result;
1081 }
Dan Williams91c00922007-01-02 13:52:30 -07001082
1083 set_bit(STRIPE_HANDLE, &sh->state);
1084 release_stripe(sh);
1085}
1086
1087static void
Dan Williamsac6b53b2009-07-14 13:40:19 -07001088ops_run_reconstruct5(struct stripe_head *sh, struct raid5_percpu *percpu,
1089 struct dma_async_tx_descriptor *tx)
Dan Williams91c00922007-01-02 13:52:30 -07001090{
Dan Williams91c00922007-01-02 13:52:30 -07001091 int disks = sh->disks;
Dan Williamsd6f38f32009-07-14 11:50:52 -07001092 struct page **xor_srcs = percpu->scribble;
Dan Williamsa08abd82009-06-03 11:43:59 -07001093 struct async_submit_ctl submit;
Dan Williams91c00922007-01-02 13:52:30 -07001094 int count = 0, pd_idx = sh->pd_idx, i;
1095 struct page *xor_dest;
Dan Williamsd8ee0722008-06-28 08:32:06 +10001096 int prexor = 0;
Dan Williams91c00922007-01-02 13:52:30 -07001097 unsigned long flags;
Dan Williams91c00922007-01-02 13:52:30 -07001098
Harvey Harrisone46b2722008-04-28 02:15:50 -07001099 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -07001100 (unsigned long long)sh->sector);
1101
1102 /* check if prexor is active which means only process blocks
1103 * that are part of a read-modify-write (written)
1104 */
Dan Williamsd8ee0722008-06-28 08:32:06 +10001105 if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) {
1106 prexor = 1;
Dan Williams91c00922007-01-02 13:52:30 -07001107 xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page;
1108 for (i = disks; i--; ) {
1109 struct r5dev *dev = &sh->dev[i];
1110 if (dev->written)
1111 xor_srcs[count++] = dev->page;
1112 }
1113 } else {
1114 xor_dest = sh->dev[pd_idx].page;
1115 for (i = disks; i--; ) {
1116 struct r5dev *dev = &sh->dev[i];
1117 if (i != pd_idx)
1118 xor_srcs[count++] = dev->page;
1119 }
1120 }
1121
Dan Williams91c00922007-01-02 13:52:30 -07001122 /* 1/ if we prexor'd then the dest is reused as a source
1123 * 2/ if we did not prexor then we are redoing the parity
1124 * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
1125 * for the synchronous xor case
1126 */
Dan Williams88ba2aa2009-04-09 16:16:18 -07001127 flags = ASYNC_TX_ACK |
Dan Williams91c00922007-01-02 13:52:30 -07001128 (prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST);
1129
1130 atomic_inc(&sh->count);
1131
Dan Williamsac6b53b2009-07-14 13:40:19 -07001132 init_async_submit(&submit, flags, tx, ops_complete_reconstruct, sh,
Dan Williamsd6f38f32009-07-14 11:50:52 -07001133 to_addr_conv(sh, percpu));
Dan Williamsa08abd82009-06-03 11:43:59 -07001134 if (unlikely(count == 1))
1135 tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
1136 else
1137 tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
Dan Williams91c00922007-01-02 13:52:30 -07001138}
1139
Dan Williamsac6b53b2009-07-14 13:40:19 -07001140static void
1141ops_run_reconstruct6(struct stripe_head *sh, struct raid5_percpu *percpu,
1142 struct dma_async_tx_descriptor *tx)
1143{
1144 struct async_submit_ctl submit;
1145 struct page **blocks = percpu->scribble;
1146 int count;
1147
1148 pr_debug("%s: stripe %llu\n", __func__, (unsigned long long)sh->sector);
1149
1150 count = set_syndrome_sources(blocks, sh);
1151
1152 atomic_inc(&sh->count);
1153
1154 init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_reconstruct,
1155 sh, to_addr_conv(sh, percpu));
1156 async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
Dan Williams91c00922007-01-02 13:52:30 -07001157}
1158
1159static void ops_complete_check(void *stripe_head_ref)
1160{
1161 struct stripe_head *sh = stripe_head_ref;
Dan Williams91c00922007-01-02 13:52:30 -07001162
Harvey Harrisone46b2722008-04-28 02:15:50 -07001163 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -07001164 (unsigned long long)sh->sector);
1165
Dan Williamsecc65c92008-06-28 08:31:57 +10001166 sh->check_state = check_state_check_result;
Dan Williams91c00922007-01-02 13:52:30 -07001167 set_bit(STRIPE_HANDLE, &sh->state);
1168 release_stripe(sh);
1169}
1170
Dan Williamsac6b53b2009-07-14 13:40:19 -07001171static void ops_run_check_p(struct stripe_head *sh, struct raid5_percpu *percpu)
Dan Williams91c00922007-01-02 13:52:30 -07001172{
Dan Williams91c00922007-01-02 13:52:30 -07001173 int disks = sh->disks;
Dan Williamsac6b53b2009-07-14 13:40:19 -07001174 int pd_idx = sh->pd_idx;
1175 int qd_idx = sh->qd_idx;
1176 struct page *xor_dest;
Dan Williamsd6f38f32009-07-14 11:50:52 -07001177 struct page **xor_srcs = percpu->scribble;
Dan Williams91c00922007-01-02 13:52:30 -07001178 struct dma_async_tx_descriptor *tx;
Dan Williamsa08abd82009-06-03 11:43:59 -07001179 struct async_submit_ctl submit;
Dan Williamsac6b53b2009-07-14 13:40:19 -07001180 int count;
1181 int i;
Dan Williams91c00922007-01-02 13:52:30 -07001182
Harvey Harrisone46b2722008-04-28 02:15:50 -07001183 pr_debug("%s: stripe %llu\n", __func__,
Dan Williams91c00922007-01-02 13:52:30 -07001184 (unsigned long long)sh->sector);
1185
Dan Williamsac6b53b2009-07-14 13:40:19 -07001186 count = 0;
1187 xor_dest = sh->dev[pd_idx].page;
1188 xor_srcs[count++] = xor_dest;
Dan Williams91c00922007-01-02 13:52:30 -07001189 for (i = disks; i--; ) {
Dan Williamsac6b53b2009-07-14 13:40:19 -07001190 if (i == pd_idx || i == qd_idx)
1191 continue;
1192 xor_srcs[count++] = sh->dev[i].page;
Dan Williams91c00922007-01-02 13:52:30 -07001193 }
1194
Dan Williamsd6f38f32009-07-14 11:50:52 -07001195 init_async_submit(&submit, 0, NULL, NULL, NULL,
1196 to_addr_conv(sh, percpu));
Dan Williams099f53c2009-04-08 14:28:37 -07001197 tx = async_xor_val(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
Dan Williamsa08abd82009-06-03 11:43:59 -07001198 &sh->ops.zero_sum_result, &submit);
Dan Williams91c00922007-01-02 13:52:30 -07001199
Dan Williams91c00922007-01-02 13:52:30 -07001200 atomic_inc(&sh->count);
Dan Williamsa08abd82009-06-03 11:43:59 -07001201 init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_check, sh, NULL);
1202 tx = async_trigger_callback(&submit);
Dan Williams91c00922007-01-02 13:52:30 -07001203}
1204
Dan Williamsac6b53b2009-07-14 13:40:19 -07001205static void ops_run_check_pq(struct stripe_head *sh, struct raid5_percpu *percpu, int checkp)
1206{
1207 struct page **srcs = percpu->scribble;
1208 struct async_submit_ctl submit;
1209 int count;
1210
1211 pr_debug("%s: stripe %llu checkp: %d\n", __func__,
1212 (unsigned long long)sh->sector, checkp);
1213
1214 count = set_syndrome_sources(srcs, sh);
1215 if (!checkp)
1216 srcs[count] = NULL;
1217
1218 atomic_inc(&sh->count);
1219 init_async_submit(&submit, ASYNC_TX_ACK, NULL, ops_complete_check,
1220 sh, to_addr_conv(sh, percpu));
1221 async_syndrome_val(srcs, 0, count+2, STRIPE_SIZE,
1222 &sh->ops.zero_sum_result, percpu->spare_page, &submit);
1223}
1224
Dan Williams417b8d42009-10-16 16:25:22 +11001225static void __raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
Dan Williams91c00922007-01-02 13:52:30 -07001226{
1227 int overlap_clear = 0, i, disks = sh->disks;
1228 struct dma_async_tx_descriptor *tx = NULL;
Dan Williamsd6f38f32009-07-14 11:50:52 -07001229 raid5_conf_t *conf = sh->raid_conf;
Dan Williamsac6b53b2009-07-14 13:40:19 -07001230 int level = conf->level;
Dan Williamsd6f38f32009-07-14 11:50:52 -07001231 struct raid5_percpu *percpu;
1232 unsigned long cpu;
Dan Williams91c00922007-01-02 13:52:30 -07001233
Dan Williamsd6f38f32009-07-14 11:50:52 -07001234 cpu = get_cpu();
1235 percpu = per_cpu_ptr(conf->percpu, cpu);
Dan Williams83de75c2008-06-28 08:31:58 +10001236 if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) {
Dan Williams91c00922007-01-02 13:52:30 -07001237 ops_run_biofill(sh);
1238 overlap_clear++;
1239 }
1240
Dan Williams7b3a8712008-06-28 08:32:09 +10001241 if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) {
Dan Williamsac6b53b2009-07-14 13:40:19 -07001242 if (level < 6)
1243 tx = ops_run_compute5(sh, percpu);
1244 else {
1245 if (sh->ops.target2 < 0 || sh->ops.target < 0)
1246 tx = ops_run_compute6_1(sh, percpu);
1247 else
1248 tx = ops_run_compute6_2(sh, percpu);
1249 }
1250 /* terminate the chain if reconstruct is not set to be run */
1251 if (tx && !test_bit(STRIPE_OP_RECONSTRUCT, &ops_request))
Dan Williams7b3a8712008-06-28 08:32:09 +10001252 async_tx_ack(tx);
1253 }
Dan Williams91c00922007-01-02 13:52:30 -07001254
Dan Williams600aa102008-06-28 08:32:05 +10001255 if (test_bit(STRIPE_OP_PREXOR, &ops_request))
Dan Williamsd6f38f32009-07-14 11:50:52 -07001256 tx = ops_run_prexor(sh, percpu, tx);
Dan Williams91c00922007-01-02 13:52:30 -07001257
Dan Williams600aa102008-06-28 08:32:05 +10001258 if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) {
Dan Williamsd8ee0722008-06-28 08:32:06 +10001259 tx = ops_run_biodrain(sh, tx);
Dan Williams91c00922007-01-02 13:52:30 -07001260 overlap_clear++;
1261 }
1262
Dan Williamsac6b53b2009-07-14 13:40:19 -07001263 if (test_bit(STRIPE_OP_RECONSTRUCT, &ops_request)) {
1264 if (level < 6)
1265 ops_run_reconstruct5(sh, percpu, tx);
1266 else
1267 ops_run_reconstruct6(sh, percpu, tx);
1268 }
Dan Williams91c00922007-01-02 13:52:30 -07001269
Dan Williamsac6b53b2009-07-14 13:40:19 -07001270 if (test_bit(STRIPE_OP_CHECK, &ops_request)) {
1271 if (sh->check_state == check_state_run)
1272 ops_run_check_p(sh, percpu);
1273 else if (sh->check_state == check_state_run_q)
1274 ops_run_check_pq(sh, percpu, 0);
1275 else if (sh->check_state == check_state_run_pq)
1276 ops_run_check_pq(sh, percpu, 1);
1277 else
1278 BUG();
1279 }
Dan Williams91c00922007-01-02 13:52:30 -07001280
Dan Williams91c00922007-01-02 13:52:30 -07001281 if (overlap_clear)
1282 for (i = disks; i--; ) {
1283 struct r5dev *dev = &sh->dev[i];
1284 if (test_and_clear_bit(R5_Overlap, &dev->flags))
1285 wake_up(&sh->raid_conf->wait_for_overlap);
1286 }
Dan Williamsd6f38f32009-07-14 11:50:52 -07001287 put_cpu();
Dan Williams91c00922007-01-02 13:52:30 -07001288}
1289
Dan Williams417b8d42009-10-16 16:25:22 +11001290#ifdef CONFIG_MULTICORE_RAID456
1291static void async_run_ops(void *param, async_cookie_t cookie)
1292{
1293 struct stripe_head *sh = param;
1294 unsigned long ops_request = sh->ops.request;
1295
1296 clear_bit_unlock(STRIPE_OPS_REQ_PENDING, &sh->state);
1297 wake_up(&sh->ops.wait_for_ops);
1298
1299 __raid_run_ops(sh, ops_request);
1300 release_stripe(sh);
1301}
1302
1303static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
1304{
1305 /* since handle_stripe can be called outside of raid5d context
1306 * we need to ensure sh->ops.request is de-staged before another
1307 * request arrives
1308 */
1309 wait_event(sh->ops.wait_for_ops,
1310 !test_and_set_bit_lock(STRIPE_OPS_REQ_PENDING, &sh->state));
1311 sh->ops.request = ops_request;
1312
1313 atomic_inc(&sh->count);
1314 async_schedule(async_run_ops, sh);
1315}
1316#else
1317#define raid_run_ops __raid_run_ops
1318#endif
1319
NeilBrown3f294f42005-11-08 21:39:25 -08001320static int grow_one_stripe(raid5_conf_t *conf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001321{
1322 struct stripe_head *sh;
NeilBrown3f294f42005-11-08 21:39:25 -08001323 sh = kmem_cache_alloc(conf->slab_cache, GFP_KERNEL);
1324 if (!sh)
1325 return 0;
NeilBrowne4e11e32010-06-16 16:45:16 +10001326 memset(sh, 0, sizeof(*sh) + (conf->pool_size-1)*sizeof(struct r5dev));
NeilBrown3f294f42005-11-08 21:39:25 -08001327 sh->raid_conf = conf;
1328 spin_lock_init(&sh->lock);
Dan Williams417b8d42009-10-16 16:25:22 +11001329 #ifdef CONFIG_MULTICORE_RAID456
1330 init_waitqueue_head(&sh->ops.wait_for_ops);
1331 #endif
NeilBrown3f294f42005-11-08 21:39:25 -08001332
NeilBrowne4e11e32010-06-16 16:45:16 +10001333 if (grow_buffers(sh)) {
1334 shrink_buffers(sh);
NeilBrown3f294f42005-11-08 21:39:25 -08001335 kmem_cache_free(conf->slab_cache, sh);
1336 return 0;
1337 }
1338 /* we just created an active stripe so... */
1339 atomic_set(&sh->count, 1);
1340 atomic_inc(&conf->active_stripes);
1341 INIT_LIST_HEAD(&sh->lru);
1342 release_stripe(sh);
1343 return 1;
1344}
1345
1346static int grow_stripes(raid5_conf_t *conf, int num)
1347{
Christoph Lametere18b8902006-12-06 20:33:20 -08001348 struct kmem_cache *sc;
NeilBrown5e5e3e72009-10-16 16:35:30 +11001349 int devs = max(conf->raid_disks, conf->previous_raid_disks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350
NeilBrownf4be6b42010-06-01 19:37:25 +10001351 if (conf->mddev->gendisk)
1352 sprintf(conf->cache_name[0],
1353 "raid%d-%s", conf->level, mdname(conf->mddev));
1354 else
1355 sprintf(conf->cache_name[0],
1356 "raid%d-%p", conf->level, conf->mddev);
1357 sprintf(conf->cache_name[1], "%s-alt", conf->cache_name[0]);
1358
NeilBrownad01c9e2006-03-27 01:18:07 -08001359 conf->active_name = 0;
1360 sc = kmem_cache_create(conf->cache_name[conf->active_name],
Linus Torvalds1da177e2005-04-16 15:20:36 -07001361 sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev),
Paul Mundt20c2df82007-07-20 10:11:58 +09001362 0, 0, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363 if (!sc)
1364 return 1;
1365 conf->slab_cache = sc;
NeilBrownad01c9e2006-03-27 01:18:07 -08001366 conf->pool_size = devs;
NeilBrown16a53ec2006-06-26 00:27:38 -07001367 while (num--)
NeilBrown3f294f42005-11-08 21:39:25 -08001368 if (!grow_one_stripe(conf))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370 return 0;
1371}
NeilBrown29269552006-03-27 01:18:10 -08001372
Dan Williamsd6f38f32009-07-14 11:50:52 -07001373/**
1374 * scribble_len - return the required size of the scribble region
1375 * @num - total number of disks in the array
1376 *
1377 * The size must be enough to contain:
1378 * 1/ a struct page pointer for each device in the array +2
1379 * 2/ room to convert each entry in (1) to its corresponding dma
1380 * (dma_map_page()) or page (page_address()) address.
1381 *
1382 * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
1383 * calculate over all devices (not just the data blocks), using zeros in place
1384 * of the P and Q blocks.
1385 */
1386static size_t scribble_len(int num)
1387{
1388 size_t len;
1389
1390 len = sizeof(struct page *) * (num+2) + sizeof(addr_conv_t) * (num+2);
1391
1392 return len;
1393}
1394
NeilBrownad01c9e2006-03-27 01:18:07 -08001395static int resize_stripes(raid5_conf_t *conf, int newsize)
1396{
1397 /* Make all the stripes able to hold 'newsize' devices.
1398 * New slots in each stripe get 'page' set to a new page.
1399 *
1400 * This happens in stages:
1401 * 1/ create a new kmem_cache and allocate the required number of
1402 * stripe_heads.
1403 * 2/ gather all the old stripe_heads and tranfer the pages across
1404 * to the new stripe_heads. This will have the side effect of
1405 * freezing the array as once all stripe_heads have been collected,
1406 * no IO will be possible. Old stripe heads are freed once their
1407 * pages have been transferred over, and the old kmem_cache is
1408 * freed when all stripes are done.
1409 * 3/ reallocate conf->disks to be suitable bigger. If this fails,
1410 * we simple return a failre status - no need to clean anything up.
1411 * 4/ allocate new pages for the new slots in the new stripe_heads.
1412 * If this fails, we don't bother trying the shrink the
1413 * stripe_heads down again, we just leave them as they are.
1414 * As each stripe_head is processed the new one is released into
1415 * active service.
1416 *
1417 * Once step2 is started, we cannot afford to wait for a write,
1418 * so we use GFP_NOIO allocations.
1419 */
1420 struct stripe_head *osh, *nsh;
1421 LIST_HEAD(newstripes);
1422 struct disk_info *ndisks;
Dan Williamsd6f38f32009-07-14 11:50:52 -07001423 unsigned long cpu;
Dan Williamsb5470dc2008-06-27 21:44:04 -07001424 int err;
Christoph Lametere18b8902006-12-06 20:33:20 -08001425 struct kmem_cache *sc;
NeilBrownad01c9e2006-03-27 01:18:07 -08001426 int i;
1427
1428 if (newsize <= conf->pool_size)
1429 return 0; /* never bother to shrink */
1430
Dan Williamsb5470dc2008-06-27 21:44:04 -07001431 err = md_allow_write(conf->mddev);
1432 if (err)
1433 return err;
NeilBrown2a2275d2007-01-26 00:57:11 -08001434
NeilBrownad01c9e2006-03-27 01:18:07 -08001435 /* Step 1 */
1436 sc = kmem_cache_create(conf->cache_name[1-conf->active_name],
1437 sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev),
Paul Mundt20c2df82007-07-20 10:11:58 +09001438 0, 0, NULL);
NeilBrownad01c9e2006-03-27 01:18:07 -08001439 if (!sc)
1440 return -ENOMEM;
1441
1442 for (i = conf->max_nr_stripes; i; i--) {
1443 nsh = kmem_cache_alloc(sc, GFP_KERNEL);
1444 if (!nsh)
1445 break;
1446
1447 memset(nsh, 0, sizeof(*nsh) + (newsize-1)*sizeof(struct r5dev));
1448
1449 nsh->raid_conf = conf;
1450 spin_lock_init(&nsh->lock);
Dan Williams417b8d42009-10-16 16:25:22 +11001451 #ifdef CONFIG_MULTICORE_RAID456
1452 init_waitqueue_head(&nsh->ops.wait_for_ops);
1453 #endif
NeilBrownad01c9e2006-03-27 01:18:07 -08001454
1455 list_add(&nsh->lru, &newstripes);
1456 }
1457 if (i) {
1458 /* didn't get enough, give up */
1459 while (!list_empty(&newstripes)) {
1460 nsh = list_entry(newstripes.next, struct stripe_head, lru);
1461 list_del(&nsh->lru);
1462 kmem_cache_free(sc, nsh);
1463 }
1464 kmem_cache_destroy(sc);
1465 return -ENOMEM;
1466 }
1467 /* Step 2 - Must use GFP_NOIO now.
1468 * OK, we have enough stripes, start collecting inactive
1469 * stripes and copying them over
1470 */
1471 list_for_each_entry(nsh, &newstripes, lru) {
1472 spin_lock_irq(&conf->device_lock);
1473 wait_event_lock_irq(conf->wait_for_stripe,
1474 !list_empty(&conf->inactive_list),
1475 conf->device_lock,
NeilBrownb3b46be2006-03-27 01:18:16 -08001476 unplug_slaves(conf->mddev)
NeilBrownad01c9e2006-03-27 01:18:07 -08001477 );
1478 osh = get_free_stripe(conf);
1479 spin_unlock_irq(&conf->device_lock);
1480 atomic_set(&nsh->count, 1);
1481 for(i=0; i<conf->pool_size; i++)
1482 nsh->dev[i].page = osh->dev[i].page;
1483 for( ; i<newsize; i++)
1484 nsh->dev[i].page = NULL;
1485 kmem_cache_free(conf->slab_cache, osh);
1486 }
1487 kmem_cache_destroy(conf->slab_cache);
1488
1489 /* Step 3.
1490 * At this point, we are holding all the stripes so the array
1491 * is completely stalled, so now is a good time to resize
Dan Williamsd6f38f32009-07-14 11:50:52 -07001492 * conf->disks and the scribble region
NeilBrownad01c9e2006-03-27 01:18:07 -08001493 */
1494 ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO);
1495 if (ndisks) {
1496 for (i=0; i<conf->raid_disks; i++)
1497 ndisks[i] = conf->disks[i];
1498 kfree(conf->disks);
1499 conf->disks = ndisks;
1500 } else
1501 err = -ENOMEM;
1502
Dan Williamsd6f38f32009-07-14 11:50:52 -07001503 get_online_cpus();
1504 conf->scribble_len = scribble_len(newsize);
1505 for_each_present_cpu(cpu) {
1506 struct raid5_percpu *percpu;
1507 void *scribble;
1508
1509 percpu = per_cpu_ptr(conf->percpu, cpu);
1510 scribble = kmalloc(conf->scribble_len, GFP_NOIO);
1511
1512 if (scribble) {
1513 kfree(percpu->scribble);
1514 percpu->scribble = scribble;
1515 } else {
1516 err = -ENOMEM;
1517 break;
1518 }
1519 }
1520 put_online_cpus();
1521
NeilBrownad01c9e2006-03-27 01:18:07 -08001522 /* Step 4, return new stripes to service */
1523 while(!list_empty(&newstripes)) {
1524 nsh = list_entry(newstripes.next, struct stripe_head, lru);
1525 list_del_init(&nsh->lru);
Dan Williamsd6f38f32009-07-14 11:50:52 -07001526
NeilBrownad01c9e2006-03-27 01:18:07 -08001527 for (i=conf->raid_disks; i < newsize; i++)
1528 if (nsh->dev[i].page == NULL) {
1529 struct page *p = alloc_page(GFP_NOIO);
1530 nsh->dev[i].page = p;
1531 if (!p)
1532 err = -ENOMEM;
1533 }
1534 release_stripe(nsh);
1535 }
1536 /* critical section pass, GFP_NOIO no longer needed */
1537
1538 conf->slab_cache = sc;
1539 conf->active_name = 1-conf->active_name;
1540 conf->pool_size = newsize;
1541 return err;
1542}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001543
NeilBrown3f294f42005-11-08 21:39:25 -08001544static int drop_one_stripe(raid5_conf_t *conf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001545{
1546 struct stripe_head *sh;
1547
NeilBrown3f294f42005-11-08 21:39:25 -08001548 spin_lock_irq(&conf->device_lock);
1549 sh = get_free_stripe(conf);
1550 spin_unlock_irq(&conf->device_lock);
1551 if (!sh)
1552 return 0;
Eric Sesterhenn78bafeb2006-04-02 13:31:42 +02001553 BUG_ON(atomic_read(&sh->count));
NeilBrowne4e11e32010-06-16 16:45:16 +10001554 shrink_buffers(sh);
NeilBrown3f294f42005-11-08 21:39:25 -08001555 kmem_cache_free(conf->slab_cache, sh);
1556 atomic_dec(&conf->active_stripes);
1557 return 1;
1558}
1559
1560static void shrink_stripes(raid5_conf_t *conf)
1561{
1562 while (drop_one_stripe(conf))
1563 ;
1564
NeilBrown29fc7e32006-02-03 03:03:41 -08001565 if (conf->slab_cache)
1566 kmem_cache_destroy(conf->slab_cache);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001567 conf->slab_cache = NULL;
1568}
1569
NeilBrown6712ecf2007-09-27 12:47:43 +02001570static void raid5_end_read_request(struct bio * bi, int error)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001571{
NeilBrown99c0fb52009-03-31 14:39:38 +11001572 struct stripe_head *sh = bi->bi_private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573 raid5_conf_t *conf = sh->raid_conf;
NeilBrown7ecaa1e2006-03-27 01:18:08 -08001574 int disks = sh->disks, i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001575 int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags);
NeilBrownd6950432006-07-10 04:44:20 -07001576 char b[BDEVNAME_SIZE];
1577 mdk_rdev_t *rdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001578
Linus Torvalds1da177e2005-04-16 15:20:36 -07001579
1580 for (i=0 ; i<disks; i++)
1581 if (bi == &sh->dev[i].req)
1582 break;
1583
Dan Williams45b42332007-07-09 11:56:43 -07001584 pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n",
1585 (unsigned long long)sh->sector, i, atomic_read(&sh->count),
Linus Torvalds1da177e2005-04-16 15:20:36 -07001586 uptodate);
1587 if (i == disks) {
1588 BUG();
NeilBrown6712ecf2007-09-27 12:47:43 +02001589 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001590 }
1591
1592 if (uptodate) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593 set_bit(R5_UPTODATE, &sh->dev[i].flags);
NeilBrown4e5314b2005-11-08 21:39:22 -08001594 if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
NeilBrownd6950432006-07-10 04:44:20 -07001595 rdev = conf->disks[i].rdev;
NeilBrown0c55e022010-05-03 14:09:02 +10001596 printk_rl(KERN_INFO "md/raid:%s: read error corrected"
Bernd Schubert6be9d492008-05-23 13:04:34 -07001597 " (%lu sectors at %llu on %s)\n",
1598 mdname(conf->mddev), STRIPE_SECTORS,
1599 (unsigned long long)(sh->sector
1600 + rdev->data_offset),
1601 bdevname(rdev->bdev, b));
NeilBrown4e5314b2005-11-08 21:39:22 -08001602 clear_bit(R5_ReadError, &sh->dev[i].flags);
1603 clear_bit(R5_ReWrite, &sh->dev[i].flags);
1604 }
NeilBrownba22dcb2005-11-08 21:39:31 -08001605 if (atomic_read(&conf->disks[i].rdev->read_errors))
1606 atomic_set(&conf->disks[i].rdev->read_errors, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001607 } else {
NeilBrownd6950432006-07-10 04:44:20 -07001608 const char *bdn = bdevname(conf->disks[i].rdev->bdev, b);
NeilBrownba22dcb2005-11-08 21:39:31 -08001609 int retry = 0;
NeilBrownd6950432006-07-10 04:44:20 -07001610 rdev = conf->disks[i].rdev;
1611
Linus Torvalds1da177e2005-04-16 15:20:36 -07001612 clear_bit(R5_UPTODATE, &sh->dev[i].flags);
NeilBrownd6950432006-07-10 04:44:20 -07001613 atomic_inc(&rdev->read_errors);
Gabriele A. Trombetti7b0bb532010-04-28 11:51:17 +10001614 if (conf->mddev->degraded >= conf->max_degraded)
Bernd Schubert6be9d492008-05-23 13:04:34 -07001615 printk_rl(KERN_WARNING
NeilBrown0c55e022010-05-03 14:09:02 +10001616 "md/raid:%s: read error not correctable "
Bernd Schubert6be9d492008-05-23 13:04:34 -07001617 "(sector %llu on %s).\n",
1618 mdname(conf->mddev),
1619 (unsigned long long)(sh->sector
1620 + rdev->data_offset),
1621 bdn);
NeilBrownba22dcb2005-11-08 21:39:31 -08001622 else if (test_bit(R5_ReWrite, &sh->dev[i].flags))
NeilBrown4e5314b2005-11-08 21:39:22 -08001623 /* Oh, no!!! */
Bernd Schubert6be9d492008-05-23 13:04:34 -07001624 printk_rl(KERN_WARNING
NeilBrown0c55e022010-05-03 14:09:02 +10001625 "md/raid:%s: read error NOT corrected!! "
Bernd Schubert6be9d492008-05-23 13:04:34 -07001626 "(sector %llu on %s).\n",
1627 mdname(conf->mddev),
1628 (unsigned long long)(sh->sector
1629 + rdev->data_offset),
1630 bdn);
NeilBrownd6950432006-07-10 04:44:20 -07001631 else if (atomic_read(&rdev->read_errors)
NeilBrownba22dcb2005-11-08 21:39:31 -08001632 > conf->max_nr_stripes)
NeilBrown14f8d262006-01-06 00:20:14 -08001633 printk(KERN_WARNING
NeilBrown0c55e022010-05-03 14:09:02 +10001634 "md/raid:%s: Too many read errors, failing device %s.\n",
NeilBrownd6950432006-07-10 04:44:20 -07001635 mdname(conf->mddev), bdn);
NeilBrownba22dcb2005-11-08 21:39:31 -08001636 else
1637 retry = 1;
1638 if (retry)
1639 set_bit(R5_ReadError, &sh->dev[i].flags);
1640 else {
NeilBrown4e5314b2005-11-08 21:39:22 -08001641 clear_bit(R5_ReadError, &sh->dev[i].flags);
1642 clear_bit(R5_ReWrite, &sh->dev[i].flags);
NeilBrownd6950432006-07-10 04:44:20 -07001643 md_error(conf->mddev, rdev);
NeilBrownba22dcb2005-11-08 21:39:31 -08001644 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001645 }
1646 rdev_dec_pending(conf->disks[i].rdev, conf->mddev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001647 clear_bit(R5_LOCKED, &sh->dev[i].flags);
1648 set_bit(STRIPE_HANDLE, &sh->state);
1649 release_stripe(sh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001650}
1651
NeilBrownd710e132008-10-13 11:55:12 +11001652static void raid5_end_write_request(struct bio *bi, int error)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653{
NeilBrown99c0fb52009-03-31 14:39:38 +11001654 struct stripe_head *sh = bi->bi_private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001655 raid5_conf_t *conf = sh->raid_conf;
NeilBrown7ecaa1e2006-03-27 01:18:08 -08001656 int disks = sh->disks, i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags);
1658
Linus Torvalds1da177e2005-04-16 15:20:36 -07001659 for (i=0 ; i<disks; i++)
1660 if (bi == &sh->dev[i].req)
1661 break;
1662
Dan Williams45b42332007-07-09 11:56:43 -07001663 pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001664 (unsigned long long)sh->sector, i, atomic_read(&sh->count),
1665 uptodate);
1666 if (i == disks) {
1667 BUG();
NeilBrown6712ecf2007-09-27 12:47:43 +02001668 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669 }
1670
Linus Torvalds1da177e2005-04-16 15:20:36 -07001671 if (!uptodate)
1672 md_error(conf->mddev, conf->disks[i].rdev);
1673
1674 rdev_dec_pending(conf->disks[i].rdev, conf->mddev);
1675
1676 clear_bit(R5_LOCKED, &sh->dev[i].flags);
1677 set_bit(STRIPE_HANDLE, &sh->state);
NeilBrownc04be0a2006-10-03 01:15:53 -07001678 release_stripe(sh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001679}
1680
1681
NeilBrown784052e2009-03-31 15:19:07 +11001682static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001683
NeilBrown784052e2009-03-31 15:19:07 +11001684static void raid5_build_block(struct stripe_head *sh, int i, int previous)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685{
1686 struct r5dev *dev = &sh->dev[i];
1687
1688 bio_init(&dev->req);
1689 dev->req.bi_io_vec = &dev->vec;
1690 dev->req.bi_vcnt++;
1691 dev->req.bi_max_vecs++;
1692 dev->vec.bv_page = dev->page;
1693 dev->vec.bv_len = STRIPE_SIZE;
1694 dev->vec.bv_offset = 0;
1695
1696 dev->req.bi_sector = sh->sector;
1697 dev->req.bi_private = sh;
1698
1699 dev->flags = 0;
NeilBrown784052e2009-03-31 15:19:07 +11001700 dev->sector = compute_blocknr(sh, i, previous);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001701}
1702
1703static void error(mddev_t *mddev, mdk_rdev_t *rdev)
1704{
1705 char b[BDEVNAME_SIZE];
H Hartley Sweeten7b928132010-03-08 16:02:40 +11001706 raid5_conf_t *conf = mddev->private;
NeilBrown0c55e022010-05-03 14:09:02 +10001707 pr_debug("raid456: error called\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001708
NeilBrownb2d444d2005-11-08 21:39:31 -08001709 if (!test_bit(Faulty, &rdev->flags)) {
NeilBrown850b2b42006-10-03 01:15:46 -07001710 set_bit(MD_CHANGE_DEVS, &mddev->flags);
NeilBrownc04be0a2006-10-03 01:15:53 -07001711 if (test_and_clear_bit(In_sync, &rdev->flags)) {
1712 unsigned long flags;
1713 spin_lock_irqsave(&conf->device_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001714 mddev->degraded++;
NeilBrownc04be0a2006-10-03 01:15:53 -07001715 spin_unlock_irqrestore(&conf->device_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001716 /*
1717 * if recovery was running, make sure it aborts.
1718 */
NeilBrowndfc70642008-05-23 13:04:39 -07001719 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001720 }
NeilBrownb2d444d2005-11-08 21:39:31 -08001721 set_bit(Faulty, &rdev->flags);
NeilBrownd710e132008-10-13 11:55:12 +11001722 printk(KERN_ALERT
NeilBrown0c55e022010-05-03 14:09:02 +10001723 "md/raid:%s: Disk failure on %s, disabling device.\n"
1724 KERN_ALERT
1725 "md/raid:%s: Operation continuing on %d devices.\n",
1726 mdname(mddev),
1727 bdevname(rdev->bdev, b),
1728 mdname(mddev),
1729 conf->raid_disks - mddev->degraded);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001730 }
NeilBrown16a53ec2006-06-26 00:27:38 -07001731}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001732
1733/*
1734 * Input: a 'big' sector number,
1735 * Output: index of the data and parity disk, and the sector # in them.
1736 */
NeilBrown112bf892009-03-31 14:39:38 +11001737static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector,
NeilBrown911d4ee2009-03-31 14:39:38 +11001738 int previous, int *dd_idx,
1739 struct stripe_head *sh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001740{
NeilBrown6e3b96e2010-04-23 07:08:28 +10001741 sector_t stripe, stripe2;
NeilBrown35f2a592010-04-20 14:13:34 +10001742 sector_t chunk_number;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001743 unsigned int chunk_offset;
NeilBrown911d4ee2009-03-31 14:39:38 +11001744 int pd_idx, qd_idx;
NeilBrown67cc2b82009-03-31 14:39:38 +11001745 int ddf_layout = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001746 sector_t new_sector;
NeilBrowne183eae2009-03-31 15:20:22 +11001747 int algorithm = previous ? conf->prev_algo
1748 : conf->algorithm;
Andre Noll09c9e5f2009-06-18 08:45:55 +10001749 int sectors_per_chunk = previous ? conf->prev_chunk_sectors
1750 : conf->chunk_sectors;
NeilBrown112bf892009-03-31 14:39:38 +11001751 int raid_disks = previous ? conf->previous_raid_disks
1752 : conf->raid_disks;
1753 int data_disks = raid_disks - conf->max_degraded;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001754
1755 /* First compute the information on this sector */
1756
1757 /*
1758 * Compute the chunk number and the sector offset inside the chunk
1759 */
1760 chunk_offset = sector_div(r_sector, sectors_per_chunk);
1761 chunk_number = r_sector;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001762
1763 /*
1764 * Compute the stripe number
1765 */
NeilBrown35f2a592010-04-20 14:13:34 +10001766 stripe = chunk_number;
1767 *dd_idx = sector_div(stripe, data_disks);
NeilBrown6e3b96e2010-04-23 07:08:28 +10001768 stripe2 = stripe;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001769 /*
1770 * Select the parity disk based on the user selected algorithm.
1771 */
NeilBrown911d4ee2009-03-31 14:39:38 +11001772 pd_idx = qd_idx = ~0;
NeilBrown16a53ec2006-06-26 00:27:38 -07001773 switch(conf->level) {
1774 case 4:
NeilBrown911d4ee2009-03-31 14:39:38 +11001775 pd_idx = data_disks;
NeilBrown16a53ec2006-06-26 00:27:38 -07001776 break;
1777 case 5:
NeilBrowne183eae2009-03-31 15:20:22 +11001778 switch (algorithm) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001779 case ALGORITHM_LEFT_ASYMMETRIC:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001780 pd_idx = data_disks - sector_div(stripe2, raid_disks);
NeilBrown911d4ee2009-03-31 14:39:38 +11001781 if (*dd_idx >= pd_idx)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001782 (*dd_idx)++;
1783 break;
1784 case ALGORITHM_RIGHT_ASYMMETRIC:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001785 pd_idx = sector_div(stripe2, raid_disks);
NeilBrown911d4ee2009-03-31 14:39:38 +11001786 if (*dd_idx >= pd_idx)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001787 (*dd_idx)++;
1788 break;
1789 case ALGORITHM_LEFT_SYMMETRIC:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001790 pd_idx = data_disks - sector_div(stripe2, raid_disks);
NeilBrown911d4ee2009-03-31 14:39:38 +11001791 *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001792 break;
1793 case ALGORITHM_RIGHT_SYMMETRIC:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001794 pd_idx = sector_div(stripe2, raid_disks);
NeilBrown911d4ee2009-03-31 14:39:38 +11001795 *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001796 break;
NeilBrown99c0fb52009-03-31 14:39:38 +11001797 case ALGORITHM_PARITY_0:
1798 pd_idx = 0;
1799 (*dd_idx)++;
1800 break;
1801 case ALGORITHM_PARITY_N:
1802 pd_idx = data_disks;
1803 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001804 default:
NeilBrown99c0fb52009-03-31 14:39:38 +11001805 BUG();
NeilBrown16a53ec2006-06-26 00:27:38 -07001806 }
1807 break;
1808 case 6:
1809
NeilBrowne183eae2009-03-31 15:20:22 +11001810 switch (algorithm) {
NeilBrown16a53ec2006-06-26 00:27:38 -07001811 case ALGORITHM_LEFT_ASYMMETRIC:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001812 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
NeilBrown911d4ee2009-03-31 14:39:38 +11001813 qd_idx = pd_idx + 1;
1814 if (pd_idx == raid_disks-1) {
NeilBrown99c0fb52009-03-31 14:39:38 +11001815 (*dd_idx)++; /* Q D D D P */
NeilBrown911d4ee2009-03-31 14:39:38 +11001816 qd_idx = 0;
1817 } else if (*dd_idx >= pd_idx)
NeilBrown16a53ec2006-06-26 00:27:38 -07001818 (*dd_idx) += 2; /* D D P Q D */
1819 break;
1820 case ALGORITHM_RIGHT_ASYMMETRIC:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001821 pd_idx = sector_div(stripe2, raid_disks);
NeilBrown911d4ee2009-03-31 14:39:38 +11001822 qd_idx = pd_idx + 1;
1823 if (pd_idx == raid_disks-1) {
NeilBrown99c0fb52009-03-31 14:39:38 +11001824 (*dd_idx)++; /* Q D D D P */
NeilBrown911d4ee2009-03-31 14:39:38 +11001825 qd_idx = 0;
1826 } else if (*dd_idx >= pd_idx)
NeilBrown16a53ec2006-06-26 00:27:38 -07001827 (*dd_idx) += 2; /* D D P Q D */
1828 break;
1829 case ALGORITHM_LEFT_SYMMETRIC:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001830 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
NeilBrown911d4ee2009-03-31 14:39:38 +11001831 qd_idx = (pd_idx + 1) % raid_disks;
1832 *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks;
NeilBrown16a53ec2006-06-26 00:27:38 -07001833 break;
1834 case ALGORITHM_RIGHT_SYMMETRIC:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001835 pd_idx = sector_div(stripe2, raid_disks);
NeilBrown911d4ee2009-03-31 14:39:38 +11001836 qd_idx = (pd_idx + 1) % raid_disks;
1837 *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks;
NeilBrown16a53ec2006-06-26 00:27:38 -07001838 break;
NeilBrown99c0fb52009-03-31 14:39:38 +11001839
1840 case ALGORITHM_PARITY_0:
1841 pd_idx = 0;
1842 qd_idx = 1;
1843 (*dd_idx) += 2;
1844 break;
1845 case ALGORITHM_PARITY_N:
1846 pd_idx = data_disks;
1847 qd_idx = data_disks + 1;
1848 break;
1849
1850 case ALGORITHM_ROTATING_ZERO_RESTART:
1851 /* Exactly the same as RIGHT_ASYMMETRIC, but or
1852 * of blocks for computing Q is different.
1853 */
NeilBrown6e3b96e2010-04-23 07:08:28 +10001854 pd_idx = sector_div(stripe2, raid_disks);
NeilBrown99c0fb52009-03-31 14:39:38 +11001855 qd_idx = pd_idx + 1;
1856 if (pd_idx == raid_disks-1) {
1857 (*dd_idx)++; /* Q D D D P */
1858 qd_idx = 0;
1859 } else if (*dd_idx >= pd_idx)
1860 (*dd_idx) += 2; /* D D P Q D */
NeilBrown67cc2b82009-03-31 14:39:38 +11001861 ddf_layout = 1;
NeilBrown99c0fb52009-03-31 14:39:38 +11001862 break;
1863
1864 case ALGORITHM_ROTATING_N_RESTART:
1865 /* Same a left_asymmetric, by first stripe is
1866 * D D D P Q rather than
1867 * Q D D D P
1868 */
NeilBrown6e3b96e2010-04-23 07:08:28 +10001869 stripe2 += 1;
1870 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
NeilBrown99c0fb52009-03-31 14:39:38 +11001871 qd_idx = pd_idx + 1;
1872 if (pd_idx == raid_disks-1) {
1873 (*dd_idx)++; /* Q D D D P */
1874 qd_idx = 0;
1875 } else if (*dd_idx >= pd_idx)
1876 (*dd_idx) += 2; /* D D P Q D */
NeilBrown67cc2b82009-03-31 14:39:38 +11001877 ddf_layout = 1;
NeilBrown99c0fb52009-03-31 14:39:38 +11001878 break;
1879
1880 case ALGORITHM_ROTATING_N_CONTINUE:
1881 /* Same as left_symmetric but Q is before P */
NeilBrown6e3b96e2010-04-23 07:08:28 +10001882 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
NeilBrown99c0fb52009-03-31 14:39:38 +11001883 qd_idx = (pd_idx + raid_disks - 1) % raid_disks;
1884 *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
NeilBrown67cc2b82009-03-31 14:39:38 +11001885 ddf_layout = 1;
NeilBrown99c0fb52009-03-31 14:39:38 +11001886 break;
1887
1888 case ALGORITHM_LEFT_ASYMMETRIC_6:
1889 /* RAID5 left_asymmetric, with Q on last device */
NeilBrown6e3b96e2010-04-23 07:08:28 +10001890 pd_idx = data_disks - sector_div(stripe2, raid_disks-1);
NeilBrown99c0fb52009-03-31 14:39:38 +11001891 if (*dd_idx >= pd_idx)
1892 (*dd_idx)++;
1893 qd_idx = raid_disks - 1;
1894 break;
1895
1896 case ALGORITHM_RIGHT_ASYMMETRIC_6:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001897 pd_idx = sector_div(stripe2, raid_disks-1);
NeilBrown99c0fb52009-03-31 14:39:38 +11001898 if (*dd_idx >= pd_idx)
1899 (*dd_idx)++;
1900 qd_idx = raid_disks - 1;
1901 break;
1902
1903 case ALGORITHM_LEFT_SYMMETRIC_6:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001904 pd_idx = data_disks - sector_div(stripe2, raid_disks-1);
NeilBrown99c0fb52009-03-31 14:39:38 +11001905 *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1);
1906 qd_idx = raid_disks - 1;
1907 break;
1908
1909 case ALGORITHM_RIGHT_SYMMETRIC_6:
NeilBrown6e3b96e2010-04-23 07:08:28 +10001910 pd_idx = sector_div(stripe2, raid_disks-1);
NeilBrown99c0fb52009-03-31 14:39:38 +11001911 *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1);
1912 qd_idx = raid_disks - 1;
1913 break;
1914
1915 case ALGORITHM_PARITY_0_6:
1916 pd_idx = 0;
1917 (*dd_idx)++;
1918 qd_idx = raid_disks - 1;
1919 break;
1920
NeilBrown16a53ec2006-06-26 00:27:38 -07001921 default:
NeilBrown99c0fb52009-03-31 14:39:38 +11001922 BUG();
NeilBrown16a53ec2006-06-26 00:27:38 -07001923 }
1924 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001925 }
1926
NeilBrown911d4ee2009-03-31 14:39:38 +11001927 if (sh) {
1928 sh->pd_idx = pd_idx;
1929 sh->qd_idx = qd_idx;
NeilBrown67cc2b82009-03-31 14:39:38 +11001930 sh->ddf_layout = ddf_layout;
NeilBrown911d4ee2009-03-31 14:39:38 +11001931 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001932 /*
1933 * Finally, compute the new sector number
1934 */
1935 new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset;
1936 return new_sector;
1937}
1938
1939
NeilBrown784052e2009-03-31 15:19:07 +11001940static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001941{
1942 raid5_conf_t *conf = sh->raid_conf;
NeilBrownb875e532006-12-10 02:20:49 -08001943 int raid_disks = sh->disks;
1944 int data_disks = raid_disks - conf->max_degraded;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001945 sector_t new_sector = sh->sector, check;
Andre Noll09c9e5f2009-06-18 08:45:55 +10001946 int sectors_per_chunk = previous ? conf->prev_chunk_sectors
1947 : conf->chunk_sectors;
NeilBrowne183eae2009-03-31 15:20:22 +11001948 int algorithm = previous ? conf->prev_algo
1949 : conf->algorithm;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001950 sector_t stripe;
1951 int chunk_offset;
NeilBrown35f2a592010-04-20 14:13:34 +10001952 sector_t chunk_number;
1953 int dummy1, dd_idx = i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001954 sector_t r_sector;
NeilBrown911d4ee2009-03-31 14:39:38 +11001955 struct stripe_head sh2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001956
NeilBrown16a53ec2006-06-26 00:27:38 -07001957
Linus Torvalds1da177e2005-04-16 15:20:36 -07001958 chunk_offset = sector_div(new_sector, sectors_per_chunk);
1959 stripe = new_sector;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001960
NeilBrown16a53ec2006-06-26 00:27:38 -07001961 if (i == sh->pd_idx)
1962 return 0;
1963 switch(conf->level) {
1964 case 4: break;
1965 case 5:
NeilBrowne183eae2009-03-31 15:20:22 +11001966 switch (algorithm) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001967 case ALGORITHM_LEFT_ASYMMETRIC:
1968 case ALGORITHM_RIGHT_ASYMMETRIC:
1969 if (i > sh->pd_idx)
1970 i--;
1971 break;
1972 case ALGORITHM_LEFT_SYMMETRIC:
1973 case ALGORITHM_RIGHT_SYMMETRIC:
1974 if (i < sh->pd_idx)
1975 i += raid_disks;
1976 i -= (sh->pd_idx + 1);
1977 break;
NeilBrown99c0fb52009-03-31 14:39:38 +11001978 case ALGORITHM_PARITY_0:
1979 i -= 1;
1980 break;
1981 case ALGORITHM_PARITY_N:
1982 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001983 default:
NeilBrown99c0fb52009-03-31 14:39:38 +11001984 BUG();
NeilBrown16a53ec2006-06-26 00:27:38 -07001985 }
1986 break;
1987 case 6:
NeilBrownd0dabf72009-03-31 14:39:38 +11001988 if (i == sh->qd_idx)
NeilBrown16a53ec2006-06-26 00:27:38 -07001989 return 0; /* It is the Q disk */
NeilBrowne183eae2009-03-31 15:20:22 +11001990 switch (algorithm) {
NeilBrown16a53ec2006-06-26 00:27:38 -07001991 case ALGORITHM_LEFT_ASYMMETRIC:
1992 case ALGORITHM_RIGHT_ASYMMETRIC:
NeilBrown99c0fb52009-03-31 14:39:38 +11001993 case ALGORITHM_ROTATING_ZERO_RESTART:
1994 case ALGORITHM_ROTATING_N_RESTART:
1995 if (sh->pd_idx == raid_disks-1)
1996 i--; /* Q D D D P */
NeilBrown16a53ec2006-06-26 00:27:38 -07001997 else if (i > sh->pd_idx)
1998 i -= 2; /* D D P Q D */
1999 break;
2000 case ALGORITHM_LEFT_SYMMETRIC:
2001 case ALGORITHM_RIGHT_SYMMETRIC:
2002 if (sh->pd_idx == raid_disks-1)
2003 i--; /* Q D D D P */
2004 else {
2005 /* D D P Q D */
2006 if (i < sh->pd_idx)
2007 i += raid_disks;
2008 i -= (sh->pd_idx + 2);
2009 }
2010 break;
NeilBrown99c0fb52009-03-31 14:39:38 +11002011 case ALGORITHM_PARITY_0:
2012 i -= 2;
2013 break;
2014 case ALGORITHM_PARITY_N:
2015 break;
2016 case ALGORITHM_ROTATING_N_CONTINUE:
NeilBrowne4424fe2009-10-16 16:27:34 +11002017 /* Like left_symmetric, but P is before Q */
NeilBrown99c0fb52009-03-31 14:39:38 +11002018 if (sh->pd_idx == 0)
2019 i--; /* P D D D Q */
NeilBrowne4424fe2009-10-16 16:27:34 +11002020 else {
2021 /* D D Q P D */
2022 if (i < sh->pd_idx)
2023 i += raid_disks;
2024 i -= (sh->pd_idx + 1);
2025 }
NeilBrown99c0fb52009-03-31 14:39:38 +11002026 break;
2027 case ALGORITHM_LEFT_ASYMMETRIC_6:
2028 case ALGORITHM_RIGHT_ASYMMETRIC_6:
2029 if (i > sh->pd_idx)
2030 i--;
2031 break;
2032 case ALGORITHM_LEFT_SYMMETRIC_6:
2033 case ALGORITHM_RIGHT_SYMMETRIC_6:
2034 if (i < sh->pd_idx)
2035 i += data_disks + 1;
2036 i -= (sh->pd_idx + 1);
2037 break;
2038 case ALGORITHM_PARITY_0_6:
2039 i -= 1;
2040 break;
NeilBrown16a53ec2006-06-26 00:27:38 -07002041 default:
NeilBrown99c0fb52009-03-31 14:39:38 +11002042 BUG();
NeilBrown16a53ec2006-06-26 00:27:38 -07002043 }
2044 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002045 }
2046
2047 chunk_number = stripe * data_disks + i;
NeilBrown35f2a592010-04-20 14:13:34 +10002048 r_sector = chunk_number * sectors_per_chunk + chunk_offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002049
NeilBrown112bf892009-03-31 14:39:38 +11002050 check = raid5_compute_sector(conf, r_sector,
NeilBrown784052e2009-03-31 15:19:07 +11002051 previous, &dummy1, &sh2);
NeilBrown911d4ee2009-03-31 14:39:38 +11002052 if (check != sh->sector || dummy1 != dd_idx || sh2.pd_idx != sh->pd_idx
2053 || sh2.qd_idx != sh->qd_idx) {
NeilBrown0c55e022010-05-03 14:09:02 +10002054 printk(KERN_ERR "md/raid:%s: compute_blocknr: map not correct\n",
2055 mdname(conf->mddev));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002056 return 0;
2057 }
2058 return r_sector;
2059}
2060
2061
Dan Williams600aa102008-06-28 08:32:05 +10002062static void
Yuri Tikhonovc0f7bdd2009-08-29 19:13:12 -07002063schedule_reconstruction(struct stripe_head *sh, struct stripe_head_state *s,
Dan Williams600aa102008-06-28 08:32:05 +10002064 int rcw, int expand)
Dan Williamse33129d2007-01-02 13:52:30 -07002065{
2066 int i, pd_idx = sh->pd_idx, disks = sh->disks;
Yuri Tikhonovc0f7bdd2009-08-29 19:13:12 -07002067 raid5_conf_t *conf = sh->raid_conf;
2068 int level = conf->level;
NeilBrown16a53ec2006-06-26 00:27:38 -07002069
Dan Williamse33129d2007-01-02 13:52:30 -07002070 if (rcw) {
2071 /* if we are not expanding this is a proper write request, and
2072 * there will be bios with new data to be drained into the
2073 * stripe cache
2074 */
2075 if (!expand) {
Dan Williams600aa102008-06-28 08:32:05 +10002076 sh->reconstruct_state = reconstruct_state_drain_run;
2077 set_bit(STRIPE_OP_BIODRAIN, &s->ops_request);
2078 } else
2079 sh->reconstruct_state = reconstruct_state_run;
Dan Williamse33129d2007-01-02 13:52:30 -07002080
Dan Williamsac6b53b2009-07-14 13:40:19 -07002081 set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request);
Dan Williamse33129d2007-01-02 13:52:30 -07002082
2083 for (i = disks; i--; ) {
2084 struct r5dev *dev = &sh->dev[i];
2085
2086 if (dev->towrite) {
2087 set_bit(R5_LOCKED, &dev->flags);
Dan Williamsd8ee0722008-06-28 08:32:06 +10002088 set_bit(R5_Wantdrain, &dev->flags);
Dan Williamse33129d2007-01-02 13:52:30 -07002089 if (!expand)
2090 clear_bit(R5_UPTODATE, &dev->flags);
Dan Williams600aa102008-06-28 08:32:05 +10002091 s->locked++;
Dan Williamse33129d2007-01-02 13:52:30 -07002092 }
2093 }
Yuri Tikhonovc0f7bdd2009-08-29 19:13:12 -07002094 if (s->locked + conf->max_degraded == disks)
Dan Williams8b3e6cd2008-04-28 02:15:53 -07002095 if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state))
Yuri Tikhonovc0f7bdd2009-08-29 19:13:12 -07002096 atomic_inc(&conf->pending_full_writes);
Dan Williamse33129d2007-01-02 13:52:30 -07002097 } else {
Yuri Tikhonovc0f7bdd2009-08-29 19:13:12 -07002098 BUG_ON(level == 6);
Dan Williamse33129d2007-01-02 13:52:30 -07002099 BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) ||
2100 test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags)));
2101
Dan Williamsd8ee0722008-06-28 08:32:06 +10002102 sh->reconstruct_state = reconstruct_state_prexor_drain_run;
Dan Williams600aa102008-06-28 08:32:05 +10002103 set_bit(STRIPE_OP_PREXOR, &s->ops_request);
2104 set_bit(STRIPE_OP_BIODRAIN, &s->ops_request);
Dan Williamsac6b53b2009-07-14 13:40:19 -07002105 set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request);
Dan Williamse33129d2007-01-02 13:52:30 -07002106
2107 for (i = disks; i--; ) {
2108 struct r5dev *dev = &sh->dev[i];
2109 if (i == pd_idx)
2110 continue;
2111
Dan Williamse33129d2007-01-02 13:52:30 -07002112 if (dev->towrite &&
2113 (test_bit(R5_UPTODATE, &dev->flags) ||
Dan Williamsd8ee0722008-06-28 08:32:06 +10002114 test_bit(R5_Wantcompute, &dev->flags))) {
2115 set_bit(R5_Wantdrain, &dev->flags);
Dan Williamse33129d2007-01-02 13:52:30 -07002116 set_bit(R5_LOCKED, &dev->flags);
2117 clear_bit(R5_UPTODATE, &dev->flags);
Dan Williams600aa102008-06-28 08:32:05 +10002118 s->locked++;
Dan Williamse33129d2007-01-02 13:52:30 -07002119 }
2120 }
2121 }
2122
Yuri Tikhonovc0f7bdd2009-08-29 19:13:12 -07002123 /* keep the parity disk(s) locked while asynchronous operations
Dan Williamse33129d2007-01-02 13:52:30 -07002124 * are in flight
2125 */
2126 set_bit(R5_LOCKED, &sh->dev[pd_idx].flags);
2127 clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
Dan Williams600aa102008-06-28 08:32:05 +10002128 s->locked++;
Dan Williamse33129d2007-01-02 13:52:30 -07002129
Yuri Tikhonovc0f7bdd2009-08-29 19:13:12 -07002130 if (level == 6) {
2131 int qd_idx = sh->qd_idx;
2132 struct r5dev *dev = &sh->dev[qd_idx];
2133
2134 set_bit(R5_LOCKED, &dev->flags);
2135 clear_bit(R5_UPTODATE, &dev->flags);
2136 s->locked++;
2137 }
2138
Dan Williams600aa102008-06-28 08:32:05 +10002139 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
Harvey Harrisone46b2722008-04-28 02:15:50 -07002140 __func__, (unsigned long long)sh->sector,
Dan Williams600aa102008-06-28 08:32:05 +10002141 s->locked, s->ops_request);
Dan Williamse33129d2007-01-02 13:52:30 -07002142}
NeilBrown16a53ec2006-06-26 00:27:38 -07002143
Linus Torvalds1da177e2005-04-16 15:20:36 -07002144/*
2145 * Each stripe/dev can have one or more bion attached.
NeilBrown16a53ec2006-06-26 00:27:38 -07002146 * toread/towrite point to the first in a chain.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002147 * The bi_next chain must be in order.
2148 */
2149static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite)
2150{
2151 struct bio **bip;
2152 raid5_conf_t *conf = sh->raid_conf;
NeilBrown72626682005-09-09 16:23:54 -07002153 int firstwrite=0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002154
Dan Williams45b42332007-07-09 11:56:43 -07002155 pr_debug("adding bh b#%llu to stripe s#%llu\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002156 (unsigned long long)bi->bi_sector,
2157 (unsigned long long)sh->sector);
2158
2159
2160 spin_lock(&sh->lock);
2161 spin_lock_irq(&conf->device_lock);
NeilBrown72626682005-09-09 16:23:54 -07002162 if (forwrite) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002163 bip = &sh->dev[dd_idx].towrite;
NeilBrown72626682005-09-09 16:23:54 -07002164 if (*bip == NULL && sh->dev[dd_idx].written == NULL)
2165 firstwrite = 1;
2166 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -07002167 bip = &sh->dev[dd_idx].toread;
2168 while (*bip && (*bip)->bi_sector < bi->bi_sector) {
2169 if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector)
2170 goto overlap;
2171 bip = & (*bip)->bi_next;
2172 }
2173 if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9))
2174 goto overlap;
2175
Eric Sesterhenn78bafeb2006-04-02 13:31:42 +02002176 BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002177 if (*bip)
2178 bi->bi_next = *bip;
2179 *bip = bi;
Jens Axboe960e7392008-08-15 10:41:18 +02002180 bi->bi_phys_segments++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002181 spin_unlock_irq(&conf->device_lock);
2182 spin_unlock(&sh->lock);
2183
Dan Williams45b42332007-07-09 11:56:43 -07002184 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002185 (unsigned long long)bi->bi_sector,
2186 (unsigned long long)sh->sector, dd_idx);
2187
NeilBrown72626682005-09-09 16:23:54 -07002188 if (conf->mddev->bitmap && firstwrite) {
NeilBrown72626682005-09-09 16:23:54 -07002189 bitmap_startwrite(conf->mddev->bitmap, sh->sector,
2190 STRIPE_SECTORS, 0);
NeilBrownae3c20c2006-07-10 04:44:17 -07002191 sh->bm_seq = conf->seq_flush+1;
NeilBrown72626682005-09-09 16:23:54 -07002192 set_bit(STRIPE_BIT_DELAY, &sh->state);
2193 }
2194
Linus Torvalds1da177e2005-04-16 15:20:36 -07002195 if (forwrite) {
2196 /* check if page is covered */
2197 sector_t sector = sh->dev[dd_idx].sector;
2198 for (bi=sh->dev[dd_idx].towrite;
2199 sector < sh->dev[dd_idx].sector + STRIPE_SECTORS &&
2200 bi && bi->bi_sector <= sector;
2201 bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) {
2202 if (bi->bi_sector + (bi->bi_size>>9) >= sector)
2203 sector = bi->bi_sector + (bi->bi_size>>9);
2204 }
2205 if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS)
2206 set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags);
2207 }
2208 return 1;
2209
2210 overlap:
2211 set_bit(R5_Overlap, &sh->dev[dd_idx].flags);
2212 spin_unlock_irq(&conf->device_lock);
2213 spin_unlock(&sh->lock);
2214 return 0;
2215}
2216
NeilBrown29269552006-03-27 01:18:10 -08002217static void end_reshape(raid5_conf_t *conf);
2218
NeilBrown911d4ee2009-03-31 14:39:38 +11002219static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous,
2220 struct stripe_head *sh)
NeilBrownccfcc3c2006-03-27 01:18:09 -08002221{
NeilBrown784052e2009-03-31 15:19:07 +11002222 int sectors_per_chunk =
Andre Noll09c9e5f2009-06-18 08:45:55 +10002223 previous ? conf->prev_chunk_sectors : conf->chunk_sectors;
NeilBrown911d4ee2009-03-31 14:39:38 +11002224 int dd_idx;
Coywolf Qi Hunt2d2063c2006-10-03 01:15:50 -07002225 int chunk_offset = sector_div(stripe, sectors_per_chunk);
NeilBrown112bf892009-03-31 14:39:38 +11002226 int disks = previous ? conf->previous_raid_disks : conf->raid_disks;
Coywolf Qi Hunt2d2063c2006-10-03 01:15:50 -07002227
NeilBrown112bf892009-03-31 14:39:38 +11002228 raid5_compute_sector(conf,
2229 stripe * (disks - conf->max_degraded)
NeilBrownb875e532006-12-10 02:20:49 -08002230 *sectors_per_chunk + chunk_offset,
NeilBrown112bf892009-03-31 14:39:38 +11002231 previous,
NeilBrown911d4ee2009-03-31 14:39:38 +11002232 &dd_idx, sh);
NeilBrownccfcc3c2006-03-27 01:18:09 -08002233}
2234
Dan Williamsa4456852007-07-09 11:56:43 -07002235static void
Dan Williams1fe797e2008-06-28 09:16:30 +10002236handle_failed_stripe(raid5_conf_t *conf, struct stripe_head *sh,
Dan Williamsa4456852007-07-09 11:56:43 -07002237 struct stripe_head_state *s, int disks,
2238 struct bio **return_bi)
2239{
2240 int i;
2241 for (i = disks; i--; ) {
2242 struct bio *bi;
2243 int bitmap_end = 0;
2244
2245 if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
2246 mdk_rdev_t *rdev;
2247 rcu_read_lock();
2248 rdev = rcu_dereference(conf->disks[i].rdev);
2249 if (rdev && test_bit(In_sync, &rdev->flags))
2250 /* multiple read failures in one stripe */
2251 md_error(conf->mddev, rdev);
2252 rcu_read_unlock();
2253 }
2254 spin_lock_irq(&conf->device_lock);
2255 /* fail all writes first */
2256 bi = sh->dev[i].towrite;
2257 sh->dev[i].towrite = NULL;
2258 if (bi) {
2259 s->to_write--;
2260 bitmap_end = 1;
2261 }
2262
2263 if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
2264 wake_up(&conf->wait_for_overlap);
2265
2266 while (bi && bi->bi_sector <
2267 sh->dev[i].sector + STRIPE_SECTORS) {
2268 struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector);
2269 clear_bit(BIO_UPTODATE, &bi->bi_flags);
Jens Axboe960e7392008-08-15 10:41:18 +02002270 if (!raid5_dec_bi_phys_segments(bi)) {
Dan Williamsa4456852007-07-09 11:56:43 -07002271 md_write_end(conf->mddev);
2272 bi->bi_next = *return_bi;
2273 *return_bi = bi;
2274 }
2275 bi = nextbi;
2276 }
2277 /* and fail all 'written' */
2278 bi = sh->dev[i].written;
2279 sh->dev[i].written = NULL;
2280 if (bi) bitmap_end = 1;
2281 while (bi && bi->bi_sector <
2282 sh->dev[i].sector + STRIPE_SECTORS) {
2283 struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector);
2284 clear_bit(BIO_UPTODATE, &bi->bi_flags);
Jens Axboe960e7392008-08-15 10:41:18 +02002285 if (!raid5_dec_bi_phys_segments(bi)) {
Dan Williamsa4456852007-07-09 11:56:43 -07002286 md_write_end(conf->mddev);
2287 bi->bi_next = *return_bi;
2288 *return_bi = bi;
2289 }
2290 bi = bi2;
2291 }
2292
Dan Williamsb5e98d62007-01-02 13:52:31 -07002293 /* fail any reads if this device is non-operational and
2294 * the data has not reached the cache yet.
2295 */
2296 if (!test_bit(R5_Wantfill, &sh->dev[i].flags) &&
2297 (!test_bit(R5_Insync, &sh->dev[i].flags) ||
2298 test_bit(R5_ReadError, &sh->dev[i].flags))) {
Dan Williamsa4456852007-07-09 11:56:43 -07002299 bi = sh->dev[i].toread;
2300 sh->dev[i].toread = NULL;
2301 if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
2302 wake_up(&conf->wait_for_overlap);
2303 if (bi) s->to_read--;
2304 while (bi && bi->bi_sector <
2305 sh->dev[i].sector + STRIPE_SECTORS) {
2306 struct bio *nextbi =
2307 r5_next_bio(bi, sh->dev[i].sector);
2308 clear_bit(BIO_UPTODATE, &bi->bi_flags);
Jens Axboe960e7392008-08-15 10:41:18 +02002309 if (!raid5_dec_bi_phys_segments(bi)) {
Dan Williamsa4456852007-07-09 11:56:43 -07002310 bi->bi_next = *return_bi;
2311 *return_bi = bi;
2312 }
2313 bi = nextbi;
2314 }
2315 }
2316 spin_unlock_irq(&conf->device_lock);
2317 if (bitmap_end)
2318 bitmap_endwrite(conf->mddev->bitmap, sh->sector,
2319 STRIPE_SECTORS, 0, 0);
2320 }
2321
Dan Williams8b3e6cd2008-04-28 02:15:53 -07002322 if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state))
2323 if (atomic_dec_and_test(&conf->pending_full_writes))
2324 md_wakeup_thread(conf->mddev->thread);
Dan Williamsa4456852007-07-09 11:56:43 -07002325}
2326
Dan Williams1fe797e2008-06-28 09:16:30 +10002327/* fetch_block5 - checks the given member device to see if its data needs
2328 * to be read or computed to satisfy a request.
2329 *
2330 * Returns 1 when no more member devices need to be checked, otherwise returns
2331 * 0 to tell the loop in handle_stripe_fill5 to continue
Dan Williamsf38e1212007-01-02 13:52:30 -07002332 */
Dan Williams1fe797e2008-06-28 09:16:30 +10002333static int fetch_block5(struct stripe_head *sh, struct stripe_head_state *s,
2334 int disk_idx, int disks)
Dan Williamsf38e1212007-01-02 13:52:30 -07002335{
2336 struct r5dev *dev = &sh->dev[disk_idx];
2337 struct r5dev *failed_dev = &sh->dev[s->failed_num];
2338
Dan Williamsf38e1212007-01-02 13:52:30 -07002339 /* is the data in this block needed, and can we get it? */
2340 if (!test_bit(R5_LOCKED, &dev->flags) &&
Dan Williams1fe797e2008-06-28 09:16:30 +10002341 !test_bit(R5_UPTODATE, &dev->flags) &&
2342 (dev->toread ||
2343 (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) ||
2344 s->syncing || s->expanding ||
2345 (s->failed &&
2346 (failed_dev->toread ||
2347 (failed_dev->towrite &&
2348 !test_bit(R5_OVERWRITE, &failed_dev->flags)))))) {
Dan Williams976ea8d2008-06-28 08:32:03 +10002349 /* We would like to get this block, possibly by computing it,
2350 * otherwise read it if the backing disk is insync
Dan Williamsf38e1212007-01-02 13:52:30 -07002351 */
2352 if ((s->uptodate == disks - 1) &&
Dan Williamsecc65c92008-06-28 08:31:57 +10002353 (s->failed && disk_idx == s->failed_num)) {
Dan Williams976ea8d2008-06-28 08:32:03 +10002354 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
2355 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
Dan Williamsf38e1212007-01-02 13:52:30 -07002356 set_bit(R5_Wantcompute, &dev->flags);
2357 sh->ops.target = disk_idx;
Dan Williamsac6b53b2009-07-14 13:40:19 -07002358 sh->ops.target2 = -1;
Dan Williamsf38e1212007-01-02 13:52:30 -07002359 s->req_compute = 1;
Dan Williamsf38e1212007-01-02 13:52:30 -07002360 /* Careful: from this point on 'uptodate' is in the eye
Dan Williamsac6b53b2009-07-14 13:40:19 -07002361 * of raid_run_ops which services 'compute' operations
Dan Williamsf38e1212007-01-02 13:52:30 -07002362 * before writes. R5_Wantcompute flags a block that will
2363 * be R5_UPTODATE by the time it is needed for a
2364 * subsequent operation.
2365 */
2366 s->uptodate++;
Dan Williams1fe797e2008-06-28 09:16:30 +10002367 return 1; /* uptodate + compute == disks */
Dan Williams7a1fc532008-07-10 04:54:57 -07002368 } else if (test_bit(R5_Insync, &dev->flags)) {
Dan Williamsf38e1212007-01-02 13:52:30 -07002369 set_bit(R5_LOCKED, &dev->flags);
2370 set_bit(R5_Wantread, &dev->flags);
Dan Williamsf38e1212007-01-02 13:52:30 -07002371 s->locked++;
2372 pr_debug("Reading block %d (sync=%d)\n", disk_idx,
2373 s->syncing);
2374 }
2375 }
2376
Dan Williams1fe797e2008-06-28 09:16:30 +10002377 return 0;
Dan Williamsf38e1212007-01-02 13:52:30 -07002378}
2379
Dan Williams1fe797e2008-06-28 09:16:30 +10002380/**
2381 * handle_stripe_fill5 - read or compute data to satisfy pending requests.
2382 */
2383static void handle_stripe_fill5(struct stripe_head *sh,
Dan Williamsa4456852007-07-09 11:56:43 -07002384 struct stripe_head_state *s, int disks)
2385{
2386 int i;
Dan Williamsf38e1212007-01-02 13:52:30 -07002387
Dan Williamsf38e1212007-01-02 13:52:30 -07002388 /* look for blocks to read/compute, skip this if a compute
2389 * is already in flight, or if the stripe contents are in the
2390 * midst of changing due to a write
2391 */
Dan Williams976ea8d2008-06-28 08:32:03 +10002392 if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state &&
Dan Williams1fe797e2008-06-28 09:16:30 +10002393 !sh->reconstruct_state)
Dan Williamsf38e1212007-01-02 13:52:30 -07002394 for (i = disks; i--; )
Dan Williams1fe797e2008-06-28 09:16:30 +10002395 if (fetch_block5(sh, s, i, disks))
Dan Williamsf38e1212007-01-02 13:52:30 -07002396 break;
Dan Williamsa4456852007-07-09 11:56:43 -07002397 set_bit(STRIPE_HANDLE, &sh->state);
2398}
2399
Yuri Tikhonov5599bec2009-08-29 19:13:12 -07002400/* fetch_block6 - checks the given member device to see if its data needs
2401 * to be read or computed to satisfy a request.
2402 *
2403 * Returns 1 when no more member devices need to be checked, otherwise returns
2404 * 0 to tell the loop in handle_stripe_fill6 to continue
2405 */
2406static int fetch_block6(struct stripe_head *sh, struct stripe_head_state *s,
2407 struct r6_state *r6s, int disk_idx, int disks)
2408{
2409 struct r5dev *dev = &sh->dev[disk_idx];
2410 struct r5dev *fdev[2] = { &sh->dev[r6s->failed_num[0]],
2411 &sh->dev[r6s->failed_num[1]] };
2412
2413 if (!test_bit(R5_LOCKED, &dev->flags) &&
2414 !test_bit(R5_UPTODATE, &dev->flags) &&
2415 (dev->toread ||
2416 (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) ||
2417 s->syncing || s->expanding ||
2418 (s->failed >= 1 &&
2419 (fdev[0]->toread || s->to_write)) ||
2420 (s->failed >= 2 &&
2421 (fdev[1]->toread || s->to_write)))) {
2422 /* we would like to get this block, possibly by computing it,
2423 * otherwise read it if the backing disk is insync
2424 */
2425 BUG_ON(test_bit(R5_Wantcompute, &dev->flags));
2426 BUG_ON(test_bit(R5_Wantread, &dev->flags));
2427 if ((s->uptodate == disks - 1) &&
2428 (s->failed && (disk_idx == r6s->failed_num[0] ||
2429 disk_idx == r6s->failed_num[1]))) {
2430 /* have disk failed, and we're requested to fetch it;
2431 * do compute it
2432 */
2433 pr_debug("Computing stripe %llu block %d\n",
2434 (unsigned long long)sh->sector, disk_idx);
2435 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
2436 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
2437 set_bit(R5_Wantcompute, &dev->flags);
2438 sh->ops.target = disk_idx;
2439 sh->ops.target2 = -1; /* no 2nd target */
2440 s->req_compute = 1;
2441 s->uptodate++;
2442 return 1;
2443 } else if (s->uptodate == disks-2 && s->failed >= 2) {
2444 /* Computing 2-failure is *very* expensive; only
2445 * do it if failed >= 2
2446 */
2447 int other;
2448 for (other = disks; other--; ) {
2449 if (other == disk_idx)
2450 continue;
2451 if (!test_bit(R5_UPTODATE,
2452 &sh->dev[other].flags))
2453 break;
2454 }
2455 BUG_ON(other < 0);
2456 pr_debug("Computing stripe %llu blocks %d,%d\n",
2457 (unsigned long long)sh->sector,
2458 disk_idx, other);
2459 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
2460 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
2461 set_bit(R5_Wantcompute, &sh->dev[disk_idx].flags);
2462 set_bit(R5_Wantcompute, &sh->dev[other].flags);
2463 sh->ops.target = disk_idx;
2464 sh->ops.target2 = other;
2465 s->uptodate += 2;
2466 s->req_compute = 1;
2467 return 1;
2468 } else if (test_bit(R5_Insync, &dev->flags)) {
2469 set_bit(R5_LOCKED, &dev->flags);
2470 set_bit(R5_Wantread, &dev->flags);
2471 s->locked++;
2472 pr_debug("Reading block %d (sync=%d)\n",
2473 disk_idx, s->syncing);
2474 }
2475 }
2476
2477 return 0;
2478}
2479
2480/**
2481 * handle_stripe_fill6 - read or compute data to satisfy pending requests.
2482 */
Dan Williams1fe797e2008-06-28 09:16:30 +10002483static void handle_stripe_fill6(struct stripe_head *sh,
Dan Williamsa4456852007-07-09 11:56:43 -07002484 struct stripe_head_state *s, struct r6_state *r6s,
2485 int disks)
2486{
2487 int i;
Yuri Tikhonov5599bec2009-08-29 19:13:12 -07002488
2489 /* look for blocks to read/compute, skip this if a compute
2490 * is already in flight, or if the stripe contents are in the
2491 * midst of changing due to a write
2492 */
2493 if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state &&
2494 !sh->reconstruct_state)
2495 for (i = disks; i--; )
2496 if (fetch_block6(sh, s, r6s, i, disks))
2497 break;
Dan Williamsa4456852007-07-09 11:56:43 -07002498 set_bit(STRIPE_HANDLE, &sh->state);
2499}
2500
2501
Dan Williams1fe797e2008-06-28 09:16:30 +10002502/* handle_stripe_clean_event
Dan Williamsa4456852007-07-09 11:56:43 -07002503 * any written block on an uptodate or failed drive can be returned.
2504 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
2505 * never LOCKED, so we don't need to test 'failed' directly.
2506 */
Dan Williams1fe797e2008-06-28 09:16:30 +10002507static void handle_stripe_clean_event(raid5_conf_t *conf,
Dan Williamsa4456852007-07-09 11:56:43 -07002508 struct stripe_head *sh, int disks, struct bio **return_bi)
2509{
2510 int i;
2511 struct r5dev *dev;
2512
2513 for (i = disks; i--; )
2514 if (sh->dev[i].written) {
2515 dev = &sh->dev[i];
2516 if (!test_bit(R5_LOCKED, &dev->flags) &&
2517 test_bit(R5_UPTODATE, &dev->flags)) {
2518 /* We can return any write requests */
2519 struct bio *wbi, *wbi2;
2520 int bitmap_end = 0;
Dan Williams45b42332007-07-09 11:56:43 -07002521 pr_debug("Return write for disc %d\n", i);
Dan Williamsa4456852007-07-09 11:56:43 -07002522 spin_lock_irq(&conf->device_lock);
2523 wbi = dev->written;
2524 dev->written = NULL;
2525 while (wbi && wbi->bi_sector <
2526 dev->sector + STRIPE_SECTORS) {
2527 wbi2 = r5_next_bio(wbi, dev->sector);
Jens Axboe960e7392008-08-15 10:41:18 +02002528 if (!raid5_dec_bi_phys_segments(wbi)) {
Dan Williamsa4456852007-07-09 11:56:43 -07002529 md_write_end(conf->mddev);
2530 wbi->bi_next = *return_bi;
2531 *return_bi = wbi;
2532 }
2533 wbi = wbi2;
2534 }
2535 if (dev->towrite == NULL)
2536 bitmap_end = 1;
2537 spin_unlock_irq(&conf->device_lock);
2538 if (bitmap_end)
2539 bitmap_endwrite(conf->mddev->bitmap,
2540 sh->sector,
2541 STRIPE_SECTORS,
2542 !test_bit(STRIPE_DEGRADED, &sh->state),
2543 0);
2544 }
2545 }
Dan Williams8b3e6cd2008-04-28 02:15:53 -07002546
2547 if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state))
2548 if (atomic_dec_and_test(&conf->pending_full_writes))
2549 md_wakeup_thread(conf->mddev->thread);
Dan Williamsa4456852007-07-09 11:56:43 -07002550}
2551
Dan Williams1fe797e2008-06-28 09:16:30 +10002552static void handle_stripe_dirtying5(raid5_conf_t *conf,
Dan Williamsa4456852007-07-09 11:56:43 -07002553 struct stripe_head *sh, struct stripe_head_state *s, int disks)
2554{
2555 int rmw = 0, rcw = 0, i;
2556 for (i = disks; i--; ) {
2557 /* would I have to read this buffer for read_modify_write */
2558 struct r5dev *dev = &sh->dev[i];
2559 if ((dev->towrite || i == sh->pd_idx) &&
2560 !test_bit(R5_LOCKED, &dev->flags) &&
Dan Williamsf38e1212007-01-02 13:52:30 -07002561 !(test_bit(R5_UPTODATE, &dev->flags) ||
2562 test_bit(R5_Wantcompute, &dev->flags))) {
Dan Williamsa4456852007-07-09 11:56:43 -07002563 if (test_bit(R5_Insync, &dev->flags))
2564 rmw++;
2565 else
2566 rmw += 2*disks; /* cannot read it */
2567 }
2568 /* Would I have to read this buffer for reconstruct_write */
2569 if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx &&
2570 !test_bit(R5_LOCKED, &dev->flags) &&
Dan Williamsf38e1212007-01-02 13:52:30 -07002571 !(test_bit(R5_UPTODATE, &dev->flags) ||
2572 test_bit(R5_Wantcompute, &dev->flags))) {
2573 if (test_bit(R5_Insync, &dev->flags)) rcw++;
Dan Williamsa4456852007-07-09 11:56:43 -07002574 else
2575 rcw += 2*disks;
2576 }
2577 }
Dan Williams45b42332007-07-09 11:56:43 -07002578 pr_debug("for sector %llu, rmw=%d rcw=%d\n",
Dan Williamsa4456852007-07-09 11:56:43 -07002579 (unsigned long long)sh->sector, rmw, rcw);
2580 set_bit(STRIPE_HANDLE, &sh->state);
2581 if (rmw < rcw && rmw > 0)
2582 /* prefer read-modify-write, but need to get some data */
2583 for (i = disks; i--; ) {
2584 struct r5dev *dev = &sh->dev[i];
2585 if ((dev->towrite || i == sh->pd_idx) &&
2586 !test_bit(R5_LOCKED, &dev->flags) &&
Dan Williamsf38e1212007-01-02 13:52:30 -07002587 !(test_bit(R5_UPTODATE, &dev->flags) ||
2588 test_bit(R5_Wantcompute, &dev->flags)) &&
Dan Williamsa4456852007-07-09 11:56:43 -07002589 test_bit(R5_Insync, &dev->flags)) {
2590 if (
2591 test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
Dan Williams45b42332007-07-09 11:56:43 -07002592 pr_debug("Read_old block "
Dan Williamsa4456852007-07-09 11:56:43 -07002593 "%d for r-m-w\n", i);
2594 set_bit(R5_LOCKED, &dev->flags);
2595 set_bit(R5_Wantread, &dev->flags);
2596 s->locked++;
2597 } else {
2598 set_bit(STRIPE_DELAYED, &sh->state);
2599 set_bit(STRIPE_HANDLE, &sh->state);
2600 }
2601 }
2602 }
2603 if (rcw <= rmw && rcw > 0)
2604 /* want reconstruct write, but need to get some data */
2605 for (i = disks; i--; ) {
2606 struct r5dev *dev = &sh->dev[i];
2607 if (!test_bit(R5_OVERWRITE, &dev->flags) &&
2608 i != sh->pd_idx &&
2609 !test_bit(R5_LOCKED, &dev->flags) &&
Dan Williamsf38e1212007-01-02 13:52:30 -07002610 !(test_bit(R5_UPTODATE, &dev->flags) ||
2611 test_bit(R5_Wantcompute, &dev->flags)) &&
Dan Williamsa4456852007-07-09 11:56:43 -07002612 test_bit(R5_Insync, &dev->flags)) {
2613 if (
2614 test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
Dan Williams45b42332007-07-09 11:56:43 -07002615 pr_debug("Read_old block "
Dan Williamsa4456852007-07-09 11:56:43 -07002616 "%d for Reconstruct\n", i);
2617 set_bit(R5_LOCKED, &dev->flags);
2618 set_bit(R5_Wantread, &dev->flags);
2619 s->locked++;
2620 } else {
2621 set_bit(STRIPE_DELAYED, &sh->state);
2622 set_bit(STRIPE_HANDLE, &sh->state);
2623 }
2624 }
2625 }
2626 /* now if nothing is locked, and if we have enough data,
2627 * we can start a write request
2628 */
Dan Williamsf38e1212007-01-02 13:52:30 -07002629 /* since handle_stripe can be called at any time we need to handle the
2630 * case where a compute block operation has been submitted and then a
Dan Williamsac6b53b2009-07-14 13:40:19 -07002631 * subsequent call wants to start a write request. raid_run_ops only
2632 * handles the case where compute block and reconstruct are requested
Dan Williamsf38e1212007-01-02 13:52:30 -07002633 * simultaneously. If this is not the case then new writes need to be
2634 * held off until the compute completes.
2635 */
Dan Williams976ea8d2008-06-28 08:32:03 +10002636 if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) &&
2637 (s->locked == 0 && (rcw == 0 || rmw == 0) &&
2638 !test_bit(STRIPE_BIT_DELAY, &sh->state)))
Yuri Tikhonovc0f7bdd2009-08-29 19:13:12 -07002639 schedule_reconstruction(sh, s, rcw == 0, 0);
Dan Williamsa4456852007-07-09 11:56:43 -07002640}
2641
Dan Williams1fe797e2008-06-28 09:16:30 +10002642static void handle_stripe_dirtying6(raid5_conf_t *conf,
Dan Williamsa4456852007-07-09 11:56:43 -07002643 struct stripe_head *sh, struct stripe_head_state *s,
2644 struct r6_state *r6s, int disks)
2645{
Yuri Tikhonova9b39a72009-08-29 19:13:12 -07002646 int rcw = 0, pd_idx = sh->pd_idx, i;
NeilBrown34e04e82009-03-31 15:10:16 +11002647 int qd_idx = sh->qd_idx;
Yuri Tikhonova9b39a72009-08-29 19:13:12 -07002648
2649 set_bit(STRIPE_HANDLE, &sh->state);
Dan Williamsa4456852007-07-09 11:56:43 -07002650 for (i = disks; i--; ) {
2651 struct r5dev *dev = &sh->dev[i];
Yuri Tikhonova9b39a72009-08-29 19:13:12 -07002652 /* check if we haven't enough data */
2653 if (!test_bit(R5_OVERWRITE, &dev->flags) &&
2654 i != pd_idx && i != qd_idx &&
2655 !test_bit(R5_LOCKED, &dev->flags) &&
2656 !(test_bit(R5_UPTODATE, &dev->flags) ||
2657 test_bit(R5_Wantcompute, &dev->flags))) {
2658 rcw++;
2659 if (!test_bit(R5_Insync, &dev->flags))
2660 continue; /* it's a failed drive */
2661
2662 if (
2663 test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
2664 pr_debug("Read_old stripe %llu "
2665 "block %d for Reconstruct\n",
2666 (unsigned long long)sh->sector, i);
2667 set_bit(R5_LOCKED, &dev->flags);
2668 set_bit(R5_Wantread, &dev->flags);
2669 s->locked++;
2670 } else {
2671 pr_debug("Request delayed stripe %llu "
2672 "block %d for Reconstruct\n",
2673 (unsigned long long)sh->sector, i);
2674 set_bit(STRIPE_DELAYED, &sh->state);
2675 set_bit(STRIPE_HANDLE, &sh->state);
Dan Williamsa4456852007-07-09 11:56:43 -07002676 }
2677 }
2678 }
Dan Williamsa4456852007-07-09 11:56:43 -07002679 /* now if nothing is locked, and if we have enough data, we can start a
2680 * write request
2681 */
Yuri Tikhonova9b39a72009-08-29 19:13:12 -07002682 if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) &&
2683 s->locked == 0 && rcw == 0 &&
Dan Williamsa4456852007-07-09 11:56:43 -07002684 !test_bit(STRIPE_BIT_DELAY, &sh->state)) {
Yuri Tikhonova9b39a72009-08-29 19:13:12 -07002685 schedule_reconstruction(sh, s, 1, 0);
Dan Williamsa4456852007-07-09 11:56:43 -07002686 }
2687}
2688
2689static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh,
2690 struct stripe_head_state *s, int disks)
2691{
Dan Williamsecc65c92008-06-28 08:31:57 +10002692 struct r5dev *dev = NULL;
Dan Williamse89f8962007-01-02 13:52:31 -07002693
Dan Williamsbd2ab672008-04-10 21:29:27 -07002694 set_bit(STRIPE_HANDLE, &sh->state);
2695
Dan Williamsecc65c92008-06-28 08:31:57 +10002696 switch (sh->check_state) {
2697 case check_state_idle:
2698 /* start a new check operation if there are no failures */
Dan Williamsbd2ab672008-04-10 21:29:27 -07002699 if (s->failed == 0) {
Dan Williamsbd2ab672008-04-10 21:29:27 -07002700 BUG_ON(s->uptodate != disks);
Dan Williamsecc65c92008-06-28 08:31:57 +10002701 sh->check_state = check_state_run;
2702 set_bit(STRIPE_OP_CHECK, &s->ops_request);
Dan Williamsbd2ab672008-04-10 21:29:27 -07002703 clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags);
Dan Williamsbd2ab672008-04-10 21:29:27 -07002704 s->uptodate--;
Dan Williamsecc65c92008-06-28 08:31:57 +10002705 break;
Dan Williamsbd2ab672008-04-10 21:29:27 -07002706 }
Dan Williamsa4456852007-07-09 11:56:43 -07002707 dev = &sh->dev[s->failed_num];
Dan Williamsecc65c92008-06-28 08:31:57 +10002708 /* fall through */
2709 case check_state_compute_result:
2710 sh->check_state = check_state_idle;
2711 if (!dev)
2712 dev = &sh->dev[sh->pd_idx];
2713
2714 /* check that a write has not made the stripe insync */
2715 if (test_bit(STRIPE_INSYNC, &sh->state))
2716 break;
2717
2718 /* either failed parity check, or recovery is happening */
Dan Williamsa4456852007-07-09 11:56:43 -07002719 BUG_ON(!test_bit(R5_UPTODATE, &dev->flags));
2720 BUG_ON(s->uptodate != disks);
2721
2722 set_bit(R5_LOCKED, &dev->flags);
Dan Williamsecc65c92008-06-28 08:31:57 +10002723 s->locked++;
Dan Williamsa4456852007-07-09 11:56:43 -07002724 set_bit(R5_Wantwrite, &dev->flags);
Dan Williams830ea012007-01-02 13:52:31 -07002725
Dan Williamsa4456852007-07-09 11:56:43 -07002726 clear_bit(STRIPE_DEGRADED, &sh->state);
Dan Williamsa4456852007-07-09 11:56:43 -07002727 set_bit(STRIPE_INSYNC, &sh->state);
Dan Williamsecc65c92008-06-28 08:31:57 +10002728 break;
2729 case check_state_run:
2730 break; /* we will be called again upon completion */
2731 case check_state_check_result:
2732 sh->check_state = check_state_idle;
2733
2734 /* if a failure occurred during the check operation, leave
2735 * STRIPE_INSYNC not set and let the stripe be handled again
2736 */
2737 if (s->failed)
2738 break;
2739
2740 /* handle a successful check operation, if parity is correct
2741 * we are done. Otherwise update the mismatch count and repair
2742 * parity if !MD_RECOVERY_CHECK
2743 */
Dan Williamsad283ea2009-08-29 19:09:26 -07002744 if ((sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) == 0)
Dan Williamsecc65c92008-06-28 08:31:57 +10002745 /* parity is correct (on disc,
2746 * not in buffer any more)
2747 */
2748 set_bit(STRIPE_INSYNC, &sh->state);
2749 else {
2750 conf->mddev->resync_mismatches += STRIPE_SECTORS;
2751 if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery))
2752 /* don't try to repair!! */
2753 set_bit(STRIPE_INSYNC, &sh->state);
2754 else {
2755 sh->check_state = check_state_compute_run;
Dan Williams976ea8d2008-06-28 08:32:03 +10002756 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
Dan Williamsecc65c92008-06-28 08:31:57 +10002757 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
2758 set_bit(R5_Wantcompute,
2759 &sh->dev[sh->pd_idx].flags);
2760 sh->ops.target = sh->pd_idx;
Dan Williamsac6b53b2009-07-14 13:40:19 -07002761 sh->ops.target2 = -1;
Dan Williamsecc65c92008-06-28 08:31:57 +10002762 s->uptodate++;
2763 }
2764 }
2765 break;
2766 case check_state_compute_run:
2767 break;
2768 default:
2769 printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n",
2770 __func__, sh->check_state,
2771 (unsigned long long) sh->sector);
2772 BUG();
Dan Williamsa4456852007-07-09 11:56:43 -07002773 }
2774}
2775
2776
2777static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh,
Dan Williams36d1c642009-07-14 11:48:22 -07002778 struct stripe_head_state *s,
2779 struct r6_state *r6s, int disks)
Dan Williamsa4456852007-07-09 11:56:43 -07002780{
Dan Williamsa4456852007-07-09 11:56:43 -07002781 int pd_idx = sh->pd_idx;
NeilBrown34e04e82009-03-31 15:10:16 +11002782 int qd_idx = sh->qd_idx;
Dan Williamsd82dfee2009-07-14 13:40:57 -07002783 struct r5dev *dev;
Dan Williamsa4456852007-07-09 11:56:43 -07002784
2785 set_bit(STRIPE_HANDLE, &sh->state);
2786
2787 BUG_ON(s->failed > 2);
Dan Williamsd82dfee2009-07-14 13:40:57 -07002788
Dan Williamsa4456852007-07-09 11:56:43 -07002789 /* Want to check and possibly repair P and Q.
2790 * However there could be one 'failed' device, in which
2791 * case we can only check one of them, possibly using the
2792 * other to generate missing data
2793 */
2794
Dan Williamsd82dfee2009-07-14 13:40:57 -07002795 switch (sh->check_state) {
2796 case check_state_idle:
2797 /* start a new check operation if there are < 2 failures */
Dan Williamsa4456852007-07-09 11:56:43 -07002798 if (s->failed == r6s->q_failed) {
Dan Williamsd82dfee2009-07-14 13:40:57 -07002799 /* The only possible failed device holds Q, so it
Dan Williamsa4456852007-07-09 11:56:43 -07002800 * makes sense to check P (If anything else were failed,
2801 * we would have used P to recreate it).
2802 */
Dan Williamsd82dfee2009-07-14 13:40:57 -07002803 sh->check_state = check_state_run;
Dan Williamsa4456852007-07-09 11:56:43 -07002804 }
2805 if (!r6s->q_failed && s->failed < 2) {
Dan Williamsd82dfee2009-07-14 13:40:57 -07002806 /* Q is not failed, and we didn't use it to generate
Dan Williamsa4456852007-07-09 11:56:43 -07002807 * anything, so it makes sense to check it
2808 */
Dan Williamsd82dfee2009-07-14 13:40:57 -07002809 if (sh->check_state == check_state_run)
2810 sh->check_state = check_state_run_pq;
2811 else
2812 sh->check_state = check_state_run_q;
Dan Williamsa4456852007-07-09 11:56:43 -07002813 }
Dan Williams36d1c642009-07-14 11:48:22 -07002814
Dan Williamsd82dfee2009-07-14 13:40:57 -07002815 /* discard potentially stale zero_sum_result */
2816 sh->ops.zero_sum_result = 0;
Dan Williams36d1c642009-07-14 11:48:22 -07002817
Dan Williamsd82dfee2009-07-14 13:40:57 -07002818 if (sh->check_state == check_state_run) {
2819 /* async_xor_zero_sum destroys the contents of P */
2820 clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
2821 s->uptodate--;
Dan Williamsa4456852007-07-09 11:56:43 -07002822 }
Dan Williamsd82dfee2009-07-14 13:40:57 -07002823 if (sh->check_state >= check_state_run &&
2824 sh->check_state <= check_state_run_pq) {
2825 /* async_syndrome_zero_sum preserves P and Q, so
2826 * no need to mark them !uptodate here
2827 */
2828 set_bit(STRIPE_OP_CHECK, &s->ops_request);
2829 break;
2830 }
Dan Williams36d1c642009-07-14 11:48:22 -07002831
Dan Williamsd82dfee2009-07-14 13:40:57 -07002832 /* we have 2-disk failure */
2833 BUG_ON(s->failed != 2);
2834 /* fall through */
2835 case check_state_compute_result:
2836 sh->check_state = check_state_idle;
Dan Williams36d1c642009-07-14 11:48:22 -07002837
Dan Williamsd82dfee2009-07-14 13:40:57 -07002838 /* check that a write has not made the stripe insync */
2839 if (test_bit(STRIPE_INSYNC, &sh->state))
2840 break;
Dan Williamsa4456852007-07-09 11:56:43 -07002841
2842 /* now write out any block on a failed drive,
Dan Williamsd82dfee2009-07-14 13:40:57 -07002843 * or P or Q if they were recomputed
Dan Williamsa4456852007-07-09 11:56:43 -07002844 */
Dan Williamsd82dfee2009-07-14 13:40:57 -07002845 BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */
Dan Williamsa4456852007-07-09 11:56:43 -07002846 if (s->failed == 2) {
2847 dev = &sh->dev[r6s->failed_num[1]];
2848 s->locked++;
2849 set_bit(R5_LOCKED, &dev->flags);
2850 set_bit(R5_Wantwrite, &dev->flags);
2851 }
2852 if (s->failed >= 1) {
2853 dev = &sh->dev[r6s->failed_num[0]];
2854 s->locked++;
2855 set_bit(R5_LOCKED, &dev->flags);
2856 set_bit(R5_Wantwrite, &dev->flags);
2857 }
Dan Williamsd82dfee2009-07-14 13:40:57 -07002858 if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) {
Dan Williamsa4456852007-07-09 11:56:43 -07002859 dev = &sh->dev[pd_idx];
2860 s->locked++;
2861 set_bit(R5_LOCKED, &dev->flags);
2862 set_bit(R5_Wantwrite, &dev->flags);
2863 }
Dan Williamsd82dfee2009-07-14 13:40:57 -07002864 if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) {
Dan Williamsa4456852007-07-09 11:56:43 -07002865 dev = &sh->dev[qd_idx];
2866 s->locked++;
2867 set_bit(R5_LOCKED, &dev->flags);
2868 set_bit(R5_Wantwrite, &dev->flags);
2869 }
2870 clear_bit(STRIPE_DEGRADED, &sh->state);
2871
2872 set_bit(STRIPE_INSYNC, &sh->state);
Dan Williamsd82dfee2009-07-14 13:40:57 -07002873 break;
2874 case check_state_run:
2875 case check_state_run_q:
2876 case check_state_run_pq:
2877 break; /* we will be called again upon completion */
2878 case check_state_check_result:
2879 sh->check_state = check_state_idle;
2880
2881 /* handle a successful check operation, if parity is correct
2882 * we are done. Otherwise update the mismatch count and repair
2883 * parity if !MD_RECOVERY_CHECK
2884 */
2885 if (sh->ops.zero_sum_result == 0) {
2886 /* both parities are correct */
2887 if (!s->failed)
2888 set_bit(STRIPE_INSYNC, &sh->state);
2889 else {
2890 /* in contrast to the raid5 case we can validate
2891 * parity, but still have a failure to write
2892 * back
2893 */
2894 sh->check_state = check_state_compute_result;
2895 /* Returning at this point means that we may go
2896 * off and bring p and/or q uptodate again so
2897 * we make sure to check zero_sum_result again
2898 * to verify if p or q need writeback
2899 */
2900 }
2901 } else {
2902 conf->mddev->resync_mismatches += STRIPE_SECTORS;
2903 if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery))
2904 /* don't try to repair!! */
2905 set_bit(STRIPE_INSYNC, &sh->state);
2906 else {
2907 int *target = &sh->ops.target;
2908
2909 sh->ops.target = -1;
2910 sh->ops.target2 = -1;
2911 sh->check_state = check_state_compute_run;
2912 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
2913 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
2914 if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) {
2915 set_bit(R5_Wantcompute,
2916 &sh->dev[pd_idx].flags);
2917 *target = pd_idx;
2918 target = &sh->ops.target2;
2919 s->uptodate++;
2920 }
2921 if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) {
2922 set_bit(R5_Wantcompute,
2923 &sh->dev[qd_idx].flags);
2924 *target = qd_idx;
2925 s->uptodate++;
2926 }
2927 }
2928 }
2929 break;
2930 case check_state_compute_run:
2931 break;
2932 default:
2933 printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n",
2934 __func__, sh->check_state,
2935 (unsigned long long) sh->sector);
2936 BUG();
Dan Williamsa4456852007-07-09 11:56:43 -07002937 }
2938}
2939
2940static void handle_stripe_expansion(raid5_conf_t *conf, struct stripe_head *sh,
2941 struct r6_state *r6s)
2942{
2943 int i;
2944
2945 /* We have read all the blocks in this stripe and now we need to
2946 * copy some of them into a target stripe for expand.
2947 */
Dan Williamsf0a50d32007-01-02 13:52:31 -07002948 struct dma_async_tx_descriptor *tx = NULL;
Dan Williamsa4456852007-07-09 11:56:43 -07002949 clear_bit(STRIPE_EXPAND_SOURCE, &sh->state);
2950 for (i = 0; i < sh->disks; i++)
NeilBrown34e04e82009-03-31 15:10:16 +11002951 if (i != sh->pd_idx && i != sh->qd_idx) {
NeilBrown911d4ee2009-03-31 14:39:38 +11002952 int dd_idx, j;
Dan Williamsa4456852007-07-09 11:56:43 -07002953 struct stripe_head *sh2;
Dan Williamsa08abd82009-06-03 11:43:59 -07002954 struct async_submit_ctl submit;
Dan Williamsa4456852007-07-09 11:56:43 -07002955
NeilBrown784052e2009-03-31 15:19:07 +11002956 sector_t bn = compute_blocknr(sh, i, 1);
NeilBrown911d4ee2009-03-31 14:39:38 +11002957 sector_t s = raid5_compute_sector(conf, bn, 0,
2958 &dd_idx, NULL);
NeilBrowna8c906c2009-06-09 14:39:59 +10002959 sh2 = get_active_stripe(conf, s, 0, 1, 1);
Dan Williamsa4456852007-07-09 11:56:43 -07002960 if (sh2 == NULL)
2961 /* so far only the early blocks of this stripe
2962 * have been requested. When later blocks
2963 * get requested, we will try again
2964 */
2965 continue;
2966 if (!test_bit(STRIPE_EXPANDING, &sh2->state) ||
2967 test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) {
2968 /* must have already done this block */
2969 release_stripe(sh2);
2970 continue;
2971 }
Dan Williamsf0a50d32007-01-02 13:52:31 -07002972
2973 /* place all the copies on one channel */
Dan Williamsa08abd82009-06-03 11:43:59 -07002974 init_async_submit(&submit, 0, tx, NULL, NULL, NULL);
Dan Williamsf0a50d32007-01-02 13:52:31 -07002975 tx = async_memcpy(sh2->dev[dd_idx].page,
Dan Williams88ba2aa2009-04-09 16:16:18 -07002976 sh->dev[i].page, 0, 0, STRIPE_SIZE,
Dan Williamsa08abd82009-06-03 11:43:59 -07002977 &submit);
Dan Williamsf0a50d32007-01-02 13:52:31 -07002978
Dan Williamsa4456852007-07-09 11:56:43 -07002979 set_bit(R5_Expanded, &sh2->dev[dd_idx].flags);
2980 set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags);
2981 for (j = 0; j < conf->raid_disks; j++)
2982 if (j != sh2->pd_idx &&
NeilBrownd0dabf72009-03-31 14:39:38 +11002983 (!r6s || j != sh2->qd_idx) &&
Dan Williamsa4456852007-07-09 11:56:43 -07002984 !test_bit(R5_Expanded, &sh2->dev[j].flags))
2985 break;
2986 if (j == conf->raid_disks) {
2987 set_bit(STRIPE_EXPAND_READY, &sh2->state);
2988 set_bit(STRIPE_HANDLE, &sh2->state);
2989 }
2990 release_stripe(sh2);
Dan Williamsf0a50d32007-01-02 13:52:31 -07002991
Dan Williamsa4456852007-07-09 11:56:43 -07002992 }
NeilBrowna2e08552007-09-11 15:23:36 -07002993 /* done submitting copies, wait for them to complete */
2994 if (tx) {
2995 async_tx_ack(tx);
2996 dma_wait_for_async_tx(tx);
2997 }
Dan Williamsa4456852007-07-09 11:56:43 -07002998}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002999
Dan Williams6bfe0b42008-04-30 00:52:32 -07003000
Linus Torvalds1da177e2005-04-16 15:20:36 -07003001/*
3002 * handle_stripe - do things to a stripe.
3003 *
3004 * We lock the stripe and then examine the state of various bits
3005 * to see what needs to be done.
3006 * Possible results:
3007 * return some read request which now have data
3008 * return some write requests which are safely on disc
3009 * schedule a read on some buffers
3010 * schedule a write of some buffers
3011 * return confirmation of parity correctness
3012 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07003013 * buffers are taken off read_list or write_list, and bh_cache buffers
3014 * get BH_Lock set before the stripe lock is released.
3015 *
3016 */
Dan Williamsa4456852007-07-09 11:56:43 -07003017
NeilBrown14425772009-10-16 15:55:25 +11003018static void handle_stripe5(struct stripe_head *sh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003019{
3020 raid5_conf_t *conf = sh->raid_conf;
Dan Williamsa4456852007-07-09 11:56:43 -07003021 int disks = sh->disks, i;
3022 struct bio *return_bi = NULL;
3023 struct stripe_head_state s;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003024 struct r5dev *dev;
Dan Williams6bfe0b42008-04-30 00:52:32 -07003025 mdk_rdev_t *blocked_rdev = NULL;
Dan Williamse0a115e2008-06-05 22:45:52 -07003026 int prexor;
NeilBrown729a1862009-12-14 12:49:50 +11003027 int dec_preread_active = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003028
Dan Williamsa4456852007-07-09 11:56:43 -07003029 memset(&s, 0, sizeof(s));
Dan Williams600aa102008-06-28 08:32:05 +10003030 pr_debug("handling stripe %llu, state=%#lx cnt=%d, pd_idx=%d check:%d "
3031 "reconstruct:%d\n", (unsigned long long)sh->sector, sh->state,
3032 atomic_read(&sh->count), sh->pd_idx, sh->check_state,
3033 sh->reconstruct_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003034
3035 spin_lock(&sh->lock);
3036 clear_bit(STRIPE_HANDLE, &sh->state);
3037 clear_bit(STRIPE_DELAYED, &sh->state);
3038
Dan Williamsa4456852007-07-09 11:56:43 -07003039 s.syncing = test_bit(STRIPE_SYNCING, &sh->state);
3040 s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state);
3041 s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state);
Dan Williams83de75c2008-06-28 08:31:58 +10003042
Linus Torvalds1da177e2005-04-16 15:20:36 -07003043 /* Now to look around and see what can be done */
NeilBrown9910f162006-01-06 00:20:24 -08003044 rcu_read_lock();
Linus Torvalds1da177e2005-04-16 15:20:36 -07003045 for (i=disks; i--; ) {
3046 mdk_rdev_t *rdev;
NeilBrowna9f326e2009-09-23 18:06:41 +10003047
3048 dev = &sh->dev[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07003049
Dan Williamsb5e98d62007-01-02 13:52:31 -07003050 pr_debug("check %d: state 0x%lx toread %p read %p write %p "
3051 "written %p\n", i, dev->flags, dev->toread, dev->read,
3052 dev->towrite, dev->written);
3053
3054 /* maybe we can request a biofill operation
3055 *
3056 * new wantfill requests are only permitted while
Dan Williams83de75c2008-06-28 08:31:58 +10003057 * ops_complete_biofill is guaranteed to be inactive
Dan Williamsb5e98d62007-01-02 13:52:31 -07003058 */
3059 if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread &&
Dan Williams83de75c2008-06-28 08:31:58 +10003060 !test_bit(STRIPE_BIOFILL_RUN, &sh->state))
Dan Williamsb5e98d62007-01-02 13:52:31 -07003061 set_bit(R5_Wantfill, &dev->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003062
3063 /* now count some things */
Dan Williamsa4456852007-07-09 11:56:43 -07003064 if (test_bit(R5_LOCKED, &dev->flags)) s.locked++;
3065 if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++;
Dan Williamsf38e1212007-01-02 13:52:30 -07003066 if (test_bit(R5_Wantcompute, &dev->flags)) s.compute++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003067
Dan Williamsb5e98d62007-01-02 13:52:31 -07003068 if (test_bit(R5_Wantfill, &dev->flags))
3069 s.to_fill++;
3070 else if (dev->toread)
Dan Williamsa4456852007-07-09 11:56:43 -07003071 s.to_read++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003072 if (dev->towrite) {
Dan Williamsa4456852007-07-09 11:56:43 -07003073 s.to_write++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003074 if (!test_bit(R5_OVERWRITE, &dev->flags))
Dan Williamsa4456852007-07-09 11:56:43 -07003075 s.non_overwrite++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003076 }
Dan Williamsa4456852007-07-09 11:56:43 -07003077 if (dev->written)
3078 s.written++;
NeilBrown9910f162006-01-06 00:20:24 -08003079 rdev = rcu_dereference(conf->disks[i].rdev);
NeilBrownac4090d2008-08-05 15:54:13 +10003080 if (blocked_rdev == NULL &&
3081 rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
Dan Williams6bfe0b42008-04-30 00:52:32 -07003082 blocked_rdev = rdev;
3083 atomic_inc(&rdev->nr_pending);
Dan Williams6bfe0b42008-04-30 00:52:32 -07003084 }
NeilBrown415e72d2010-06-17 17:25:21 +10003085 clear_bit(R5_Insync, &dev->flags);
3086 if (!rdev)
3087 /* Not in-sync */;
3088 else if (test_bit(In_sync, &rdev->flags))
3089 set_bit(R5_Insync, &dev->flags);
3090 else {
3091 /* could be in-sync depending on recovery/reshape status */
3092 if (sh->sector + STRIPE_SECTORS <= rdev->recovery_offset)
3093 set_bit(R5_Insync, &dev->flags);
3094 }
3095 if (!test_bit(R5_Insync, &dev->flags)) {
NeilBrown14f8d262006-01-06 00:20:14 -08003096 /* The ReadError flag will just be confusing now */
NeilBrown4e5314b2005-11-08 21:39:22 -08003097 clear_bit(R5_ReadError, &dev->flags);
3098 clear_bit(R5_ReWrite, &dev->flags);
3099 }
NeilBrown415e72d2010-06-17 17:25:21 +10003100 if (test_bit(R5_ReadError, &dev->flags))
3101 clear_bit(R5_Insync, &dev->flags);
3102 if (!test_bit(R5_Insync, &dev->flags)) {
Dan Williamsa4456852007-07-09 11:56:43 -07003103 s.failed++;
3104 s.failed_num = i;
NeilBrown415e72d2010-06-17 17:25:21 +10003105 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003106 }
NeilBrown9910f162006-01-06 00:20:24 -08003107 rcu_read_unlock();
Dan Williamsb5e98d62007-01-02 13:52:31 -07003108
Dan Williams6bfe0b42008-04-30 00:52:32 -07003109 if (unlikely(blocked_rdev)) {
NeilBrownac4090d2008-08-05 15:54:13 +10003110 if (s.syncing || s.expanding || s.expanded ||
3111 s.to_write || s.written) {
3112 set_bit(STRIPE_HANDLE, &sh->state);
3113 goto unlock;
3114 }
3115 /* There is nothing for the blocked_rdev to block */
3116 rdev_dec_pending(blocked_rdev, conf->mddev);
3117 blocked_rdev = NULL;
Dan Williams6bfe0b42008-04-30 00:52:32 -07003118 }
3119
Dan Williams83de75c2008-06-28 08:31:58 +10003120 if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) {
3121 set_bit(STRIPE_OP_BIOFILL, &s.ops_request);
3122 set_bit(STRIPE_BIOFILL_RUN, &sh->state);
3123 }
Dan Williamsb5e98d62007-01-02 13:52:31 -07003124
Dan Williams45b42332007-07-09 11:56:43 -07003125 pr_debug("locked=%d uptodate=%d to_read=%d"
Linus Torvalds1da177e2005-04-16 15:20:36 -07003126 " to_write=%d failed=%d failed_num=%d\n",
Dan Williamsa4456852007-07-09 11:56:43 -07003127 s.locked, s.uptodate, s.to_read, s.to_write,
3128 s.failed, s.failed_num);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003129 /* check if the array has lost two devices and, if so, some requests might
3130 * need to be failed
3131 */
Dan Williamsa4456852007-07-09 11:56:43 -07003132 if (s.failed > 1 && s.to_read+s.to_write+s.written)
Dan Williams1fe797e2008-06-28 09:16:30 +10003133 handle_failed_stripe(conf, sh, &s, disks, &return_bi);
Dan Williamsa4456852007-07-09 11:56:43 -07003134 if (s.failed > 1 && s.syncing) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003135 md_done_sync(conf->mddev, STRIPE_SECTORS,0);
3136 clear_bit(STRIPE_SYNCING, &sh->state);
Dan Williamsa4456852007-07-09 11:56:43 -07003137 s.syncing = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003138 }
3139
3140 /* might be able to return some write requests if the parity block
3141 * is safe, or on a failed drive
3142 */
3143 dev = &sh->dev[sh->pd_idx];
Dan Williamsa4456852007-07-09 11:56:43 -07003144 if ( s.written &&
3145 ((test_bit(R5_Insync, &dev->flags) &&
3146 !test_bit(R5_LOCKED, &dev->flags) &&
3147 test_bit(R5_UPTODATE, &dev->flags)) ||
3148 (s.failed == 1 && s.failed_num == sh->pd_idx)))
Dan Williams1fe797e2008-06-28 09:16:30 +10003149 handle_stripe_clean_event(conf, sh, disks, &return_bi);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003150
3151 /* Now we might consider reading some blocks, either to check/generate
3152 * parity, or to satisfy requests
3153 * or to load a block that is being partially written.
3154 */
Dan Williamsa4456852007-07-09 11:56:43 -07003155 if (s.to_read || s.non_overwrite ||
Dan Williams976ea8d2008-06-28 08:32:03 +10003156 (s.syncing && (s.uptodate + s.compute < disks)) || s.expanding)
Dan Williams1fe797e2008-06-28 09:16:30 +10003157 handle_stripe_fill5(sh, &s, disks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003158
Dan Williamse33129d2007-01-02 13:52:30 -07003159 /* Now we check to see if any write operations have recently
3160 * completed
3161 */
Dan Williamse0a115e2008-06-05 22:45:52 -07003162 prexor = 0;
Dan Williamsd8ee0722008-06-28 08:32:06 +10003163 if (sh->reconstruct_state == reconstruct_state_prexor_drain_result)
Dan Williamse0a115e2008-06-05 22:45:52 -07003164 prexor = 1;
Dan Williamsd8ee0722008-06-28 08:32:06 +10003165 if (sh->reconstruct_state == reconstruct_state_drain_result ||
3166 sh->reconstruct_state == reconstruct_state_prexor_drain_result) {
Dan Williams600aa102008-06-28 08:32:05 +10003167 sh->reconstruct_state = reconstruct_state_idle;
Dan Williamse33129d2007-01-02 13:52:30 -07003168
3169 /* All the 'written' buffers and the parity block are ready to
3170 * be written back to disk
3171 */
3172 BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags));
3173 for (i = disks; i--; ) {
3174 dev = &sh->dev[i];
3175 if (test_bit(R5_LOCKED, &dev->flags) &&
3176 (i == sh->pd_idx || dev->written)) {
3177 pr_debug("Writing block %d\n", i);
3178 set_bit(R5_Wantwrite, &dev->flags);
Dan Williamse0a115e2008-06-05 22:45:52 -07003179 if (prexor)
3180 continue;
Dan Williamse33129d2007-01-02 13:52:30 -07003181 if (!test_bit(R5_Insync, &dev->flags) ||
3182 (i == sh->pd_idx && s.failed == 0))
3183 set_bit(STRIPE_INSYNC, &sh->state);
3184 }
3185 }
NeilBrown729a1862009-12-14 12:49:50 +11003186 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
3187 dec_preread_active = 1;
Dan Williamse33129d2007-01-02 13:52:30 -07003188 }
3189
3190 /* Now to consider new write requests and what else, if anything
3191 * should be read. We do not handle new writes when:
3192 * 1/ A 'write' operation (copy+xor) is already in flight.
3193 * 2/ A 'check' operation is in flight, as it may clobber the parity
3194 * block.
3195 */
Dan Williams600aa102008-06-28 08:32:05 +10003196 if (s.to_write && !sh->reconstruct_state && !sh->check_state)
Dan Williams1fe797e2008-06-28 09:16:30 +10003197 handle_stripe_dirtying5(conf, sh, &s, disks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003198
3199 /* maybe we need to check and possibly fix the parity for this stripe
Dan Williamse89f8962007-01-02 13:52:31 -07003200 * Any reads will already have been scheduled, so we just see if enough
3201 * data is available. The parity check is held off while parity
3202 * dependent operations are in flight.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003203 */
Dan Williamsecc65c92008-06-28 08:31:57 +10003204 if (sh->check_state ||
3205 (s.syncing && s.locked == 0 &&
Dan Williams976ea8d2008-06-28 08:32:03 +10003206 !test_bit(STRIPE_COMPUTE_RUN, &sh->state) &&
Dan Williamsecc65c92008-06-28 08:31:57 +10003207 !test_bit(STRIPE_INSYNC, &sh->state)))
Dan Williamsa4456852007-07-09 11:56:43 -07003208 handle_parity_checks5(conf, sh, &s, disks);
Dan Williamse89f8962007-01-02 13:52:31 -07003209
Dan Williamsa4456852007-07-09 11:56:43 -07003210 if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003211 md_done_sync(conf->mddev, STRIPE_SECTORS,1);
3212 clear_bit(STRIPE_SYNCING, &sh->state);
3213 }
NeilBrown4e5314b2005-11-08 21:39:22 -08003214
3215 /* If the failed drive is just a ReadError, then we might need to progress
3216 * the repair/check process
3217 */
Dan Williamsa4456852007-07-09 11:56:43 -07003218 if (s.failed == 1 && !conf->mddev->ro &&
3219 test_bit(R5_ReadError, &sh->dev[s.failed_num].flags)
3220 && !test_bit(R5_LOCKED, &sh->dev[s.failed_num].flags)
3221 && test_bit(R5_UPTODATE, &sh->dev[s.failed_num].flags)
NeilBrown4e5314b2005-11-08 21:39:22 -08003222 ) {
Dan Williamsa4456852007-07-09 11:56:43 -07003223 dev = &sh->dev[s.failed_num];
NeilBrown4e5314b2005-11-08 21:39:22 -08003224 if (!test_bit(R5_ReWrite, &dev->flags)) {
3225 set_bit(R5_Wantwrite, &dev->flags);
3226 set_bit(R5_ReWrite, &dev->flags);
3227 set_bit(R5_LOCKED, &dev->flags);
Dan Williamsa4456852007-07-09 11:56:43 -07003228 s.locked++;
NeilBrown4e5314b2005-11-08 21:39:22 -08003229 } else {
3230 /* let's read it back */
3231 set_bit(R5_Wantread, &dev->flags);
3232 set_bit(R5_LOCKED, &dev->flags);
Dan Williamsa4456852007-07-09 11:56:43 -07003233 s.locked++;
NeilBrown4e5314b2005-11-08 21:39:22 -08003234 }
3235 }
3236
Dan Williams600aa102008-06-28 08:32:05 +10003237 /* Finish reconstruct operations initiated by the expansion process */
3238 if (sh->reconstruct_state == reconstruct_state_result) {
NeilBrownab69ae12009-03-31 15:26:47 +11003239 struct stripe_head *sh2
NeilBrowna8c906c2009-06-09 14:39:59 +10003240 = get_active_stripe(conf, sh->sector, 1, 1, 1);
NeilBrownab69ae12009-03-31 15:26:47 +11003241 if (sh2 && test_bit(STRIPE_EXPAND_SOURCE, &sh2->state)) {
3242 /* sh cannot be written until sh2 has been read.
3243 * so arrange for sh to be delayed a little
3244 */
3245 set_bit(STRIPE_DELAYED, &sh->state);
3246 set_bit(STRIPE_HANDLE, &sh->state);
3247 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE,
3248 &sh2->state))
3249 atomic_inc(&conf->preread_active_stripes);
3250 release_stripe(sh2);
3251 goto unlock;
3252 }
3253 if (sh2)
3254 release_stripe(sh2);
3255
Dan Williams600aa102008-06-28 08:32:05 +10003256 sh->reconstruct_state = reconstruct_state_idle;
Dan Williamsf0a50d32007-01-02 13:52:31 -07003257 clear_bit(STRIPE_EXPANDING, &sh->state);
Dan Williams23397882008-07-23 20:05:34 -07003258 for (i = conf->raid_disks; i--; ) {
Dan Williamsf0a50d32007-01-02 13:52:31 -07003259 set_bit(R5_Wantwrite, &sh->dev[i].flags);
Dan Williams23397882008-07-23 20:05:34 -07003260 set_bit(R5_LOCKED, &sh->dev[i].flags);
Neil Brownefe31142008-06-28 08:31:14 +10003261 s.locked++;
Dan Williams23397882008-07-23 20:05:34 -07003262 }
Dan Williamsf0a50d32007-01-02 13:52:31 -07003263 }
3264
3265 if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) &&
Dan Williams600aa102008-06-28 08:32:05 +10003266 !sh->reconstruct_state) {
NeilBrownccfcc3c2006-03-27 01:18:09 -08003267 /* Need to write out all blocks after computing parity */
3268 sh->disks = conf->raid_disks;
NeilBrown911d4ee2009-03-31 14:39:38 +11003269 stripe_set_idx(sh->sector, conf, 0, sh);
Yuri Tikhonovc0f7bdd2009-08-29 19:13:12 -07003270 schedule_reconstruction(sh, &s, 1, 1);
Dan Williams600aa102008-06-28 08:32:05 +10003271 } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) {
NeilBrownccfcc3c2006-03-27 01:18:09 -08003272 clear_bit(STRIPE_EXPAND_READY, &sh->state);
NeilBrownf6705572006-03-27 01:18:11 -08003273 atomic_dec(&conf->reshape_stripes);
NeilBrownccfcc3c2006-03-27 01:18:09 -08003274 wake_up(&conf->wait_for_overlap);
3275 md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
3276 }
3277
Dan Williams0f94e872008-01-08 15:32:53 -08003278 if (s.expanding && s.locked == 0 &&
Dan Williams976ea8d2008-06-28 08:32:03 +10003279 !test_bit(STRIPE_COMPUTE_RUN, &sh->state))
Dan Williamsa4456852007-07-09 11:56:43 -07003280 handle_stripe_expansion(conf, sh, NULL);
NeilBrownccfcc3c2006-03-27 01:18:09 -08003281
Dan Williams6bfe0b42008-04-30 00:52:32 -07003282 unlock:
Linus Torvalds1da177e2005-04-16 15:20:36 -07003283 spin_unlock(&sh->lock);
3284
Dan Williams6bfe0b42008-04-30 00:52:32 -07003285 /* wait for this device to become unblocked */
3286 if (unlikely(blocked_rdev))
3287 md_wait_for_blocked_rdev(blocked_rdev, conf->mddev);
3288
Dan Williams600aa102008-06-28 08:32:05 +10003289 if (s.ops_request)
Dan Williamsac6b53b2009-07-14 13:40:19 -07003290 raid_run_ops(sh, s.ops_request);
Dan Williamsd84e0f12007-01-02 13:52:30 -07003291
Dan Williamsc4e5ac02008-06-28 08:31:53 +10003292 ops_run_io(sh, &s);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003293
NeilBrown729a1862009-12-14 12:49:50 +11003294 if (dec_preread_active) {
3295 /* We delay this until after ops_run_io so that if make_request
Tejun Heoe9c74692010-09-03 11:56:18 +02003296 * is waiting on a flush, it won't continue until the writes
NeilBrown729a1862009-12-14 12:49:50 +11003297 * have actually been submitted.
3298 */
3299 atomic_dec(&conf->preread_active_stripes);
3300 if (atomic_read(&conf->preread_active_stripes) <
3301 IO_THRESHOLD)
3302 md_wakeup_thread(conf->mddev->thread);
3303 }
Dan Williamsa4456852007-07-09 11:56:43 -07003304 return_io(return_bi);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003305}
3306
NeilBrown14425772009-10-16 15:55:25 +11003307static void handle_stripe6(struct stripe_head *sh)
NeilBrown16a53ec2006-06-26 00:27:38 -07003308{
NeilBrownbff61972009-03-31 14:33:13 +11003309 raid5_conf_t *conf = sh->raid_conf;
NeilBrownf4168852007-02-28 20:11:53 -08003310 int disks = sh->disks;
Dan Williamsa4456852007-07-09 11:56:43 -07003311 struct bio *return_bi = NULL;
NeilBrown34e04e82009-03-31 15:10:16 +11003312 int i, pd_idx = sh->pd_idx, qd_idx = sh->qd_idx;
Dan Williamsa4456852007-07-09 11:56:43 -07003313 struct stripe_head_state s;
3314 struct r6_state r6s;
NeilBrown16a53ec2006-06-26 00:27:38 -07003315 struct r5dev *dev, *pdev, *qdev;
Dan Williams6bfe0b42008-04-30 00:52:32 -07003316 mdk_rdev_t *blocked_rdev = NULL;
NeilBrown729a1862009-12-14 12:49:50 +11003317 int dec_preread_active = 0;
NeilBrown16a53ec2006-06-26 00:27:38 -07003318
Dan Williams45b42332007-07-09 11:56:43 -07003319 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003320 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
Dan Williamsa4456852007-07-09 11:56:43 -07003321 (unsigned long long)sh->sector, sh->state,
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003322 atomic_read(&sh->count), pd_idx, qd_idx,
3323 sh->check_state, sh->reconstruct_state);
Dan Williamsa4456852007-07-09 11:56:43 -07003324 memset(&s, 0, sizeof(s));
NeilBrown16a53ec2006-06-26 00:27:38 -07003325
3326 spin_lock(&sh->lock);
3327 clear_bit(STRIPE_HANDLE, &sh->state);
3328 clear_bit(STRIPE_DELAYED, &sh->state);
3329
Dan Williamsa4456852007-07-09 11:56:43 -07003330 s.syncing = test_bit(STRIPE_SYNCING, &sh->state);
3331 s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state);
3332 s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state);
NeilBrown16a53ec2006-06-26 00:27:38 -07003333 /* Now to look around and see what can be done */
3334
3335 rcu_read_lock();
3336 for (i=disks; i--; ) {
3337 mdk_rdev_t *rdev;
3338 dev = &sh->dev[i];
NeilBrown16a53ec2006-06-26 00:27:38 -07003339
Dan Williams45b42332007-07-09 11:56:43 -07003340 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
NeilBrown16a53ec2006-06-26 00:27:38 -07003341 i, dev->flags, dev->toread, dev->towrite, dev->written);
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003342 /* maybe we can reply to a read
3343 *
3344 * new wantfill requests are only permitted while
3345 * ops_complete_biofill is guaranteed to be inactive
3346 */
3347 if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread &&
3348 !test_bit(STRIPE_BIOFILL_RUN, &sh->state))
3349 set_bit(R5_Wantfill, &dev->flags);
NeilBrown16a53ec2006-06-26 00:27:38 -07003350
3351 /* now count some things */
Dan Williamsa4456852007-07-09 11:56:43 -07003352 if (test_bit(R5_LOCKED, &dev->flags)) s.locked++;
3353 if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++;
Dan Williams2d6e4ec2009-09-16 12:11:54 -07003354 if (test_bit(R5_Wantcompute, &dev->flags)) {
3355 s.compute++;
3356 BUG_ON(s.compute > 2);
3357 }
NeilBrown16a53ec2006-06-26 00:27:38 -07003358
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003359 if (test_bit(R5_Wantfill, &dev->flags)) {
3360 s.to_fill++;
3361 } else if (dev->toread)
Dan Williamsa4456852007-07-09 11:56:43 -07003362 s.to_read++;
NeilBrown16a53ec2006-06-26 00:27:38 -07003363 if (dev->towrite) {
Dan Williamsa4456852007-07-09 11:56:43 -07003364 s.to_write++;
NeilBrown16a53ec2006-06-26 00:27:38 -07003365 if (!test_bit(R5_OVERWRITE, &dev->flags))
Dan Williamsa4456852007-07-09 11:56:43 -07003366 s.non_overwrite++;
NeilBrown16a53ec2006-06-26 00:27:38 -07003367 }
Dan Williamsa4456852007-07-09 11:56:43 -07003368 if (dev->written)
3369 s.written++;
NeilBrown16a53ec2006-06-26 00:27:38 -07003370 rdev = rcu_dereference(conf->disks[i].rdev);
NeilBrownac4090d2008-08-05 15:54:13 +10003371 if (blocked_rdev == NULL &&
3372 rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
Dan Williams6bfe0b42008-04-30 00:52:32 -07003373 blocked_rdev = rdev;
3374 atomic_inc(&rdev->nr_pending);
Dan Williams6bfe0b42008-04-30 00:52:32 -07003375 }
NeilBrown415e72d2010-06-17 17:25:21 +10003376 clear_bit(R5_Insync, &dev->flags);
3377 if (!rdev)
3378 /* Not in-sync */;
3379 else if (test_bit(In_sync, &rdev->flags))
3380 set_bit(R5_Insync, &dev->flags);
3381 else {
3382 /* in sync if before recovery_offset */
3383 if (sh->sector + STRIPE_SECTORS <= rdev->recovery_offset)
3384 set_bit(R5_Insync, &dev->flags);
3385 }
3386 if (!test_bit(R5_Insync, &dev->flags)) {
NeilBrown16a53ec2006-06-26 00:27:38 -07003387 /* The ReadError flag will just be confusing now */
3388 clear_bit(R5_ReadError, &dev->flags);
3389 clear_bit(R5_ReWrite, &dev->flags);
3390 }
NeilBrown415e72d2010-06-17 17:25:21 +10003391 if (test_bit(R5_ReadError, &dev->flags))
3392 clear_bit(R5_Insync, &dev->flags);
3393 if (!test_bit(R5_Insync, &dev->flags)) {
Dan Williamsa4456852007-07-09 11:56:43 -07003394 if (s.failed < 2)
3395 r6s.failed_num[s.failed] = i;
3396 s.failed++;
NeilBrown415e72d2010-06-17 17:25:21 +10003397 }
NeilBrown16a53ec2006-06-26 00:27:38 -07003398 }
3399 rcu_read_unlock();
Dan Williams6bfe0b42008-04-30 00:52:32 -07003400
3401 if (unlikely(blocked_rdev)) {
NeilBrownac4090d2008-08-05 15:54:13 +10003402 if (s.syncing || s.expanding || s.expanded ||
3403 s.to_write || s.written) {
3404 set_bit(STRIPE_HANDLE, &sh->state);
3405 goto unlock;
3406 }
3407 /* There is nothing for the blocked_rdev to block */
3408 rdev_dec_pending(blocked_rdev, conf->mddev);
3409 blocked_rdev = NULL;
Dan Williams6bfe0b42008-04-30 00:52:32 -07003410 }
NeilBrownac4090d2008-08-05 15:54:13 +10003411
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003412 if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) {
3413 set_bit(STRIPE_OP_BIOFILL, &s.ops_request);
3414 set_bit(STRIPE_BIOFILL_RUN, &sh->state);
3415 }
3416
Dan Williams45b42332007-07-09 11:56:43 -07003417 pr_debug("locked=%d uptodate=%d to_read=%d"
NeilBrown16a53ec2006-06-26 00:27:38 -07003418 " to_write=%d failed=%d failed_num=%d,%d\n",
Dan Williamsa4456852007-07-09 11:56:43 -07003419 s.locked, s.uptodate, s.to_read, s.to_write, s.failed,
3420 r6s.failed_num[0], r6s.failed_num[1]);
3421 /* check if the array has lost >2 devices and, if so, some requests
3422 * might need to be failed
NeilBrown16a53ec2006-06-26 00:27:38 -07003423 */
Dan Williamsa4456852007-07-09 11:56:43 -07003424 if (s.failed > 2 && s.to_read+s.to_write+s.written)
Dan Williams1fe797e2008-06-28 09:16:30 +10003425 handle_failed_stripe(conf, sh, &s, disks, &return_bi);
Dan Williamsa4456852007-07-09 11:56:43 -07003426 if (s.failed > 2 && s.syncing) {
NeilBrown16a53ec2006-06-26 00:27:38 -07003427 md_done_sync(conf->mddev, STRIPE_SECTORS,0);
3428 clear_bit(STRIPE_SYNCING, &sh->state);
Dan Williamsa4456852007-07-09 11:56:43 -07003429 s.syncing = 0;
NeilBrown16a53ec2006-06-26 00:27:38 -07003430 }
3431
3432 /*
3433 * might be able to return some write requests if the parity blocks
3434 * are safe, or on a failed drive
3435 */
3436 pdev = &sh->dev[pd_idx];
Dan Williamsa4456852007-07-09 11:56:43 -07003437 r6s.p_failed = (s.failed >= 1 && r6s.failed_num[0] == pd_idx)
3438 || (s.failed >= 2 && r6s.failed_num[1] == pd_idx);
NeilBrown34e04e82009-03-31 15:10:16 +11003439 qdev = &sh->dev[qd_idx];
3440 r6s.q_failed = (s.failed >= 1 && r6s.failed_num[0] == qd_idx)
3441 || (s.failed >= 2 && r6s.failed_num[1] == qd_idx);
NeilBrown16a53ec2006-06-26 00:27:38 -07003442
Dan Williamsa4456852007-07-09 11:56:43 -07003443 if ( s.written &&
3444 ( r6s.p_failed || ((test_bit(R5_Insync, &pdev->flags)
NeilBrown16a53ec2006-06-26 00:27:38 -07003445 && !test_bit(R5_LOCKED, &pdev->flags)
Dan Williamsa4456852007-07-09 11:56:43 -07003446 && test_bit(R5_UPTODATE, &pdev->flags)))) &&
3447 ( r6s.q_failed || ((test_bit(R5_Insync, &qdev->flags)
NeilBrown16a53ec2006-06-26 00:27:38 -07003448 && !test_bit(R5_LOCKED, &qdev->flags)
Dan Williamsa4456852007-07-09 11:56:43 -07003449 && test_bit(R5_UPTODATE, &qdev->flags)))))
Dan Williams1fe797e2008-06-28 09:16:30 +10003450 handle_stripe_clean_event(conf, sh, disks, &return_bi);
NeilBrown16a53ec2006-06-26 00:27:38 -07003451
3452 /* Now we might consider reading some blocks, either to check/generate
3453 * parity, or to satisfy requests
3454 * or to load a block that is being partially written.
3455 */
Dan Williamsa4456852007-07-09 11:56:43 -07003456 if (s.to_read || s.non_overwrite || (s.to_write && s.failed) ||
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003457 (s.syncing && (s.uptodate + s.compute < disks)) || s.expanding)
Dan Williams1fe797e2008-06-28 09:16:30 +10003458 handle_stripe_fill6(sh, &s, &r6s, disks);
NeilBrown16a53ec2006-06-26 00:27:38 -07003459
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003460 /* Now we check to see if any write operations have recently
3461 * completed
3462 */
3463 if (sh->reconstruct_state == reconstruct_state_drain_result) {
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003464
3465 sh->reconstruct_state = reconstruct_state_idle;
3466 /* All the 'written' buffers and the parity blocks are ready to
3467 * be written back to disk
3468 */
3469 BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags));
3470 BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[qd_idx].flags));
3471 for (i = disks; i--; ) {
3472 dev = &sh->dev[i];
3473 if (test_bit(R5_LOCKED, &dev->flags) &&
3474 (i == sh->pd_idx || i == qd_idx ||
3475 dev->written)) {
3476 pr_debug("Writing block %d\n", i);
3477 BUG_ON(!test_bit(R5_UPTODATE, &dev->flags));
3478 set_bit(R5_Wantwrite, &dev->flags);
3479 if (!test_bit(R5_Insync, &dev->flags) ||
3480 ((i == sh->pd_idx || i == qd_idx) &&
3481 s.failed == 0))
3482 set_bit(STRIPE_INSYNC, &sh->state);
3483 }
3484 }
NeilBrown729a1862009-12-14 12:49:50 +11003485 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
3486 dec_preread_active = 1;
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003487 }
3488
Yuri Tikhonova9b39a72009-08-29 19:13:12 -07003489 /* Now to consider new write requests and what else, if anything
3490 * should be read. We do not handle new writes when:
3491 * 1/ A 'write' operation (copy+gen_syndrome) is already in flight.
3492 * 2/ A 'check' operation is in flight, as it may clobber the parity
3493 * block.
3494 */
3495 if (s.to_write && !sh->reconstruct_state && !sh->check_state)
Dan Williams1fe797e2008-06-28 09:16:30 +10003496 handle_stripe_dirtying6(conf, sh, &s, &r6s, disks);
NeilBrown16a53ec2006-06-26 00:27:38 -07003497
3498 /* maybe we need to check and possibly fix the parity for this stripe
Dan Williamsa4456852007-07-09 11:56:43 -07003499 * Any reads will already have been scheduled, so we just see if enough
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003500 * data is available. The parity check is held off while parity
3501 * dependent operations are in flight.
NeilBrown16a53ec2006-06-26 00:27:38 -07003502 */
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003503 if (sh->check_state ||
3504 (s.syncing && s.locked == 0 &&
3505 !test_bit(STRIPE_COMPUTE_RUN, &sh->state) &&
3506 !test_bit(STRIPE_INSYNC, &sh->state)))
Dan Williams36d1c642009-07-14 11:48:22 -07003507 handle_parity_checks6(conf, sh, &s, &r6s, disks);
NeilBrown16a53ec2006-06-26 00:27:38 -07003508
Dan Williamsa4456852007-07-09 11:56:43 -07003509 if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) {
NeilBrown16a53ec2006-06-26 00:27:38 -07003510 md_done_sync(conf->mddev, STRIPE_SECTORS,1);
3511 clear_bit(STRIPE_SYNCING, &sh->state);
3512 }
3513
3514 /* If the failed drives are just a ReadError, then we might need
3515 * to progress the repair/check process
3516 */
Dan Williamsa4456852007-07-09 11:56:43 -07003517 if (s.failed <= 2 && !conf->mddev->ro)
3518 for (i = 0; i < s.failed; i++) {
3519 dev = &sh->dev[r6s.failed_num[i]];
NeilBrown16a53ec2006-06-26 00:27:38 -07003520 if (test_bit(R5_ReadError, &dev->flags)
3521 && !test_bit(R5_LOCKED, &dev->flags)
3522 && test_bit(R5_UPTODATE, &dev->flags)
3523 ) {
3524 if (!test_bit(R5_ReWrite, &dev->flags)) {
3525 set_bit(R5_Wantwrite, &dev->flags);
3526 set_bit(R5_ReWrite, &dev->flags);
3527 set_bit(R5_LOCKED, &dev->flags);
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003528 s.locked++;
NeilBrown16a53ec2006-06-26 00:27:38 -07003529 } else {
3530 /* let's read it back */
3531 set_bit(R5_Wantread, &dev->flags);
3532 set_bit(R5_LOCKED, &dev->flags);
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003533 s.locked++;
NeilBrown16a53ec2006-06-26 00:27:38 -07003534 }
3535 }
3536 }
NeilBrownf4168852007-02-28 20:11:53 -08003537
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003538 /* Finish reconstruct operations initiated by the expansion process */
3539 if (sh->reconstruct_state == reconstruct_state_result) {
3540 sh->reconstruct_state = reconstruct_state_idle;
3541 clear_bit(STRIPE_EXPANDING, &sh->state);
3542 for (i = conf->raid_disks; i--; ) {
3543 set_bit(R5_Wantwrite, &sh->dev[i].flags);
3544 set_bit(R5_LOCKED, &sh->dev[i].flags);
3545 s.locked++;
3546 }
3547 }
3548
3549 if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) &&
3550 !sh->reconstruct_state) {
NeilBrownab69ae12009-03-31 15:26:47 +11003551 struct stripe_head *sh2
NeilBrowna8c906c2009-06-09 14:39:59 +10003552 = get_active_stripe(conf, sh->sector, 1, 1, 1);
NeilBrownab69ae12009-03-31 15:26:47 +11003553 if (sh2 && test_bit(STRIPE_EXPAND_SOURCE, &sh2->state)) {
3554 /* sh cannot be written until sh2 has been read.
3555 * so arrange for sh to be delayed a little
3556 */
3557 set_bit(STRIPE_DELAYED, &sh->state);
3558 set_bit(STRIPE_HANDLE, &sh->state);
3559 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE,
3560 &sh2->state))
3561 atomic_inc(&conf->preread_active_stripes);
3562 release_stripe(sh2);
3563 goto unlock;
3564 }
3565 if (sh2)
3566 release_stripe(sh2);
3567
NeilBrownf4168852007-02-28 20:11:53 -08003568 /* Need to write out all blocks after computing P&Q */
3569 sh->disks = conf->raid_disks;
NeilBrown911d4ee2009-03-31 14:39:38 +11003570 stripe_set_idx(sh->sector, conf, 0, sh);
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003571 schedule_reconstruction(sh, &s, 1, 1);
3572 } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) {
NeilBrownf4168852007-02-28 20:11:53 -08003573 clear_bit(STRIPE_EXPAND_READY, &sh->state);
3574 atomic_dec(&conf->reshape_stripes);
3575 wake_up(&conf->wait_for_overlap);
3576 md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
3577 }
3578
Dan Williams0f94e872008-01-08 15:32:53 -08003579 if (s.expanding && s.locked == 0 &&
Dan Williams976ea8d2008-06-28 08:32:03 +10003580 !test_bit(STRIPE_COMPUTE_RUN, &sh->state))
Dan Williamsa4456852007-07-09 11:56:43 -07003581 handle_stripe_expansion(conf, sh, &r6s);
NeilBrownf4168852007-02-28 20:11:53 -08003582
Dan Williams6bfe0b42008-04-30 00:52:32 -07003583 unlock:
NeilBrown16a53ec2006-06-26 00:27:38 -07003584 spin_unlock(&sh->lock);
3585
Dan Williams6bfe0b42008-04-30 00:52:32 -07003586 /* wait for this device to become unblocked */
3587 if (unlikely(blocked_rdev))
3588 md_wait_for_blocked_rdev(blocked_rdev, conf->mddev);
3589
Yuri Tikhonov6c0069c2009-08-29 19:13:13 -07003590 if (s.ops_request)
3591 raid_run_ops(sh, s.ops_request);
3592
Dan Williamsf0e43bc2008-06-28 08:31:55 +10003593 ops_run_io(sh, &s);
3594
NeilBrown729a1862009-12-14 12:49:50 +11003595
3596 if (dec_preread_active) {
3597 /* We delay this until after ops_run_io so that if make_request
Tejun Heoe9c74692010-09-03 11:56:18 +02003598 * is waiting on a flush, it won't continue until the writes
NeilBrown729a1862009-12-14 12:49:50 +11003599 * have actually been submitted.
3600 */
3601 atomic_dec(&conf->preread_active_stripes);
3602 if (atomic_read(&conf->preread_active_stripes) <
3603 IO_THRESHOLD)
3604 md_wakeup_thread(conf->mddev->thread);
3605 }
3606
Dan Williamsa4456852007-07-09 11:56:43 -07003607 return_io(return_bi);
NeilBrown16a53ec2006-06-26 00:27:38 -07003608}
3609
NeilBrown14425772009-10-16 15:55:25 +11003610static void handle_stripe(struct stripe_head *sh)
NeilBrown16a53ec2006-06-26 00:27:38 -07003611{
3612 if (sh->raid_conf->level == 6)
NeilBrown14425772009-10-16 15:55:25 +11003613 handle_stripe6(sh);
NeilBrown16a53ec2006-06-26 00:27:38 -07003614 else
NeilBrown14425772009-10-16 15:55:25 +11003615 handle_stripe5(sh);
NeilBrown16a53ec2006-06-26 00:27:38 -07003616}
3617
Arjan van de Ven858119e2006-01-14 13:20:43 -08003618static void raid5_activate_delayed(raid5_conf_t *conf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003619{
3620 if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) {
3621 while (!list_empty(&conf->delayed_list)) {
3622 struct list_head *l = conf->delayed_list.next;
3623 struct stripe_head *sh;
3624 sh = list_entry(l, struct stripe_head, lru);
3625 list_del_init(l);
3626 clear_bit(STRIPE_DELAYED, &sh->state);
3627 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
3628 atomic_inc(&conf->preread_active_stripes);
Dan Williams8b3e6cd2008-04-28 02:15:53 -07003629 list_add_tail(&sh->lru, &conf->hold_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003630 }
NeilBrown6ed30032008-02-06 01:40:00 -08003631 } else
NeilBrown2ac87402010-06-01 19:37:29 +10003632 plugger_set_plug(&conf->plug);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003633}
3634
Arjan van de Ven858119e2006-01-14 13:20:43 -08003635static void activate_bit_delay(raid5_conf_t *conf)
NeilBrown72626682005-09-09 16:23:54 -07003636{
3637 /* device_lock is held */
3638 struct list_head head;
3639 list_add(&head, &conf->bitmap_list);
3640 list_del_init(&conf->bitmap_list);
3641 while (!list_empty(&head)) {
3642 struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru);
3643 list_del_init(&sh->lru);
3644 atomic_inc(&sh->count);
3645 __release_stripe(conf, sh);
3646 }
3647}
3648
Linus Torvalds1da177e2005-04-16 15:20:36 -07003649static void unplug_slaves(mddev_t *mddev)
3650{
NeilBrown070ec552009-06-16 16:54:21 +10003651 raid5_conf_t *conf = mddev->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003652 int i;
NeilBrown5e5e3e72009-10-16 16:35:30 +11003653 int devs = max(conf->raid_disks, conf->previous_raid_disks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003654
3655 rcu_read_lock();
NeilBrown5e5e3e72009-10-16 16:35:30 +11003656 for (i = 0; i < devs; i++) {
Suzanne Woodd6065f72005-11-08 21:39:27 -08003657 mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev);
NeilBrownb2d444d2005-11-08 21:39:31 -08003658 if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) {
Jens Axboe165125e2007-07-24 09:28:11 +02003659 struct request_queue *r_queue = bdev_get_queue(rdev->bdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003660
3661 atomic_inc(&rdev->nr_pending);
3662 rcu_read_unlock();
3663
Alan D. Brunelle2ad8b1e2007-11-07 14:26:56 -05003664 blk_unplug(r_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003665
3666 rdev_dec_pending(rdev, mddev);
3667 rcu_read_lock();
3668 }
3669 }
3670 rcu_read_unlock();
3671}
3672
NeilBrown9f7c2222010-07-26 12:04:13 +10003673void md_raid5_unplug_device(raid5_conf_t *conf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003674{
Linus Torvalds1da177e2005-04-16 15:20:36 -07003675 unsigned long flags;
3676
3677 spin_lock_irqsave(&conf->device_lock, flags);
3678
NeilBrown2ac87402010-06-01 19:37:29 +10003679 if (plugger_remove_plug(&conf->plug)) {
NeilBrown72626682005-09-09 16:23:54 -07003680 conf->seq_flush++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003681 raid5_activate_delayed(conf);
NeilBrown72626682005-09-09 16:23:54 -07003682 }
NeilBrown2ac87402010-06-01 19:37:29 +10003683 md_wakeup_thread(conf->mddev->thread);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003684
3685 spin_unlock_irqrestore(&conf->device_lock, flags);
3686
NeilBrown2ac87402010-06-01 19:37:29 +10003687 unplug_slaves(conf->mddev);
3688}
NeilBrown9f7c2222010-07-26 12:04:13 +10003689EXPORT_SYMBOL_GPL(md_raid5_unplug_device);
NeilBrown2ac87402010-06-01 19:37:29 +10003690
3691static void raid5_unplug(struct plug_handle *plug)
3692{
3693 raid5_conf_t *conf = container_of(plug, raid5_conf_t, plug);
NeilBrown9f7c2222010-07-26 12:04:13 +10003694 md_raid5_unplug_device(conf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003695}
3696
NeilBrown2ac87402010-06-01 19:37:29 +10003697static void raid5_unplug_queue(struct request_queue *q)
NeilBrownf022b2f2006-10-03 01:15:56 -07003698{
NeilBrown2ac87402010-06-01 19:37:29 +10003699 mddev_t *mddev = q->queuedata;
NeilBrown9f7c2222010-07-26 12:04:13 +10003700 md_raid5_unplug_device(mddev->private);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003701}
3702
NeilBrown11d8a6e2010-07-26 11:57:07 +10003703int md_raid5_congested(mddev_t *mddev, int bits)
NeilBrownf022b2f2006-10-03 01:15:56 -07003704{
NeilBrown070ec552009-06-16 16:54:21 +10003705 raid5_conf_t *conf = mddev->private;
NeilBrownf022b2f2006-10-03 01:15:56 -07003706
3707 /* No difference between reads and writes. Just check
3708 * how busy the stripe_cache is
3709 */
NeilBrown3fa841d2009-09-23 18:10:29 +10003710
NeilBrownf022b2f2006-10-03 01:15:56 -07003711 if (conf->inactive_blocked)
3712 return 1;
3713 if (conf->quiesce)
3714 return 1;
3715 if (list_empty_careful(&conf->inactive_list))
3716 return 1;
3717
3718 return 0;
3719}
NeilBrown11d8a6e2010-07-26 11:57:07 +10003720EXPORT_SYMBOL_GPL(md_raid5_congested);
3721
3722static int raid5_congested(void *data, int bits)
3723{
3724 mddev_t *mddev = data;
3725
3726 return mddev_congested(mddev, bits) ||
3727 md_raid5_congested(mddev, bits);
3728}
NeilBrownf022b2f2006-10-03 01:15:56 -07003729
Raz Ben-Jehuda(caro)23032a02006-12-10 02:20:45 -08003730/* We want read requests to align with chunks where possible,
3731 * but write requests don't need to.
3732 */
Alasdair G Kergoncc371e62008-07-03 09:53:43 +02003733static int raid5_mergeable_bvec(struct request_queue *q,
3734 struct bvec_merge_data *bvm,
3735 struct bio_vec *biovec)
Raz Ben-Jehuda(caro)23032a02006-12-10 02:20:45 -08003736{
3737 mddev_t *mddev = q->queuedata;
Alasdair G Kergoncc371e62008-07-03 09:53:43 +02003738 sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
Raz Ben-Jehuda(caro)23032a02006-12-10 02:20:45 -08003739 int max;
Andre Noll9d8f0362009-06-18 08:45:01 +10003740 unsigned int chunk_sectors = mddev->chunk_sectors;
Alasdair G Kergoncc371e62008-07-03 09:53:43 +02003741 unsigned int bio_sectors = bvm->bi_size >> 9;
Raz Ben-Jehuda(caro)23032a02006-12-10 02:20:45 -08003742
Alasdair G Kergoncc371e62008-07-03 09:53:43 +02003743 if ((bvm->bi_rw & 1) == WRITE)
Raz Ben-Jehuda(caro)23032a02006-12-10 02:20:45 -08003744 return biovec->bv_len; /* always allow writes to be mergeable */
3745
Andre Noll664e7c42009-06-18 08:45:27 +10003746 if (mddev->new_chunk_sectors < mddev->chunk_sectors)
3747 chunk_sectors = mddev->new_chunk_sectors;
Raz Ben-Jehuda(caro)23032a02006-12-10 02:20:45 -08003748 max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9;
3749 if (max < 0) max = 0;
3750 if (max <= biovec->bv_len && bio_sectors == 0)
3751 return biovec->bv_len;
3752 else
3753 return max;
3754}
3755
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003756
3757static int in_chunk_boundary(mddev_t *mddev, struct bio *bio)
3758{
3759 sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev);
Andre Noll9d8f0362009-06-18 08:45:01 +10003760 unsigned int chunk_sectors = mddev->chunk_sectors;
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003761 unsigned int bio_sectors = bio->bi_size >> 9;
3762
Andre Noll664e7c42009-06-18 08:45:27 +10003763 if (mddev->new_chunk_sectors < mddev->chunk_sectors)
3764 chunk_sectors = mddev->new_chunk_sectors;
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003765 return chunk_sectors >=
3766 ((sector & (chunk_sectors - 1)) + bio_sectors);
3767}
3768
3769/*
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003770 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
3771 * later sampled by raid5d.
3772 */
3773static void add_bio_to_retry(struct bio *bi,raid5_conf_t *conf)
3774{
3775 unsigned long flags;
3776
3777 spin_lock_irqsave(&conf->device_lock, flags);
3778
3779 bi->bi_next = conf->retry_read_aligned_list;
3780 conf->retry_read_aligned_list = bi;
3781
3782 spin_unlock_irqrestore(&conf->device_lock, flags);
3783 md_wakeup_thread(conf->mddev->thread);
3784}
3785
3786
3787static struct bio *remove_bio_from_retry(raid5_conf_t *conf)
3788{
3789 struct bio *bi;
3790
3791 bi = conf->retry_read_aligned;
3792 if (bi) {
3793 conf->retry_read_aligned = NULL;
3794 return bi;
3795 }
3796 bi = conf->retry_read_aligned_list;
3797 if(bi) {
Neil Brown387bb172007-02-08 14:20:29 -08003798 conf->retry_read_aligned_list = bi->bi_next;
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003799 bi->bi_next = NULL;
Jens Axboe960e7392008-08-15 10:41:18 +02003800 /*
3801 * this sets the active strip count to 1 and the processed
3802 * strip count to zero (upper 8 bits)
3803 */
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003804 bi->bi_phys_segments = 1; /* biased count of active stripes */
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003805 }
3806
3807 return bi;
3808}
3809
3810
3811/*
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003812 * The "raid5_align_endio" should check if the read succeeded and if it
3813 * did, call bio_endio on the original bio (having bio_put the new bio
3814 * first).
3815 * If the read failed..
3816 */
NeilBrown6712ecf2007-09-27 12:47:43 +02003817static void raid5_align_endio(struct bio *bi, int error)
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003818{
3819 struct bio* raid_bi = bi->bi_private;
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003820 mddev_t *mddev;
3821 raid5_conf_t *conf;
3822 int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags);
3823 mdk_rdev_t *rdev;
3824
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003825 bio_put(bi);
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003826
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003827 rdev = (void*)raid_bi->bi_next;
3828 raid_bi->bi_next = NULL;
NeilBrown2b7f2222010-03-25 16:06:03 +11003829 mddev = rdev->mddev;
3830 conf = mddev->private;
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003831
3832 rdev_dec_pending(rdev, conf->mddev);
3833
3834 if (!error && uptodate) {
NeilBrown6712ecf2007-09-27 12:47:43 +02003835 bio_endio(raid_bi, 0);
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003836 if (atomic_dec_and_test(&conf->active_aligned_reads))
3837 wake_up(&conf->wait_for_stripe);
NeilBrown6712ecf2007-09-27 12:47:43 +02003838 return;
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003839 }
3840
3841
Dan Williams45b42332007-07-09 11:56:43 -07003842 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003843
3844 add_bio_to_retry(raid_bi, conf);
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003845}
3846
Neil Brown387bb172007-02-08 14:20:29 -08003847static int bio_fits_rdev(struct bio *bi)
3848{
Jens Axboe165125e2007-07-24 09:28:11 +02003849 struct request_queue *q = bdev_get_queue(bi->bi_bdev);
Neil Brown387bb172007-02-08 14:20:29 -08003850
Martin K. Petersenae03bf62009-05-22 17:17:50 -04003851 if ((bi->bi_size>>9) > queue_max_sectors(q))
Neil Brown387bb172007-02-08 14:20:29 -08003852 return 0;
3853 blk_recount_segments(q, bi);
Martin K. Petersen8a783622010-02-26 00:20:39 -05003854 if (bi->bi_phys_segments > queue_max_segments(q))
Neil Brown387bb172007-02-08 14:20:29 -08003855 return 0;
3856
3857 if (q->merge_bvec_fn)
3858 /* it's too hard to apply the merge_bvec_fn at this stage,
3859 * just just give up
3860 */
3861 return 0;
3862
3863 return 1;
3864}
3865
3866
NeilBrown21a52c62010-04-01 15:02:13 +11003867static int chunk_aligned_read(mddev_t *mddev, struct bio * raid_bio)
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003868{
NeilBrown070ec552009-06-16 16:54:21 +10003869 raid5_conf_t *conf = mddev->private;
NeilBrown8553fe72009-12-14 12:49:47 +11003870 int dd_idx;
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003871 struct bio* align_bi;
3872 mdk_rdev_t *rdev;
3873
3874 if (!in_chunk_boundary(mddev, raid_bio)) {
Dan Williams45b42332007-07-09 11:56:43 -07003875 pr_debug("chunk_aligned_read : non aligned\n");
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003876 return 0;
3877 }
3878 /*
NeilBrown99c0fb52009-03-31 14:39:38 +11003879 * use bio_clone to make a copy of the bio
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003880 */
3881 align_bi = bio_clone(raid_bio, GFP_NOIO);
3882 if (!align_bi)
3883 return 0;
3884 /*
3885 * set bi_end_io to a new function, and set bi_private to the
3886 * original bio.
3887 */
3888 align_bi->bi_end_io = raid5_align_endio;
3889 align_bi->bi_private = raid_bio;
3890 /*
3891 * compute position
3892 */
NeilBrown112bf892009-03-31 14:39:38 +11003893 align_bi->bi_sector = raid5_compute_sector(conf, raid_bio->bi_sector,
3894 0,
NeilBrown911d4ee2009-03-31 14:39:38 +11003895 &dd_idx, NULL);
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003896
3897 rcu_read_lock();
3898 rdev = rcu_dereference(conf->disks[dd_idx].rdev);
3899 if (rdev && test_bit(In_sync, &rdev->flags)) {
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003900 atomic_inc(&rdev->nr_pending);
3901 rcu_read_unlock();
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003902 raid_bio->bi_next = (void*)rdev;
3903 align_bi->bi_bdev = rdev->bdev;
3904 align_bi->bi_flags &= ~(1 << BIO_SEG_VALID);
3905 align_bi->bi_sector += rdev->data_offset;
3906
Neil Brown387bb172007-02-08 14:20:29 -08003907 if (!bio_fits_rdev(align_bi)) {
3908 /* too big in some way */
3909 bio_put(align_bi);
3910 rdev_dec_pending(rdev, mddev);
3911 return 0;
3912 }
3913
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003914 spin_lock_irq(&conf->device_lock);
3915 wait_event_lock_irq(conf->wait_for_stripe,
3916 conf->quiesce == 0,
3917 conf->device_lock, /* nothing */);
3918 atomic_inc(&conf->active_aligned_reads);
3919 spin_unlock_irq(&conf->device_lock);
3920
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003921 generic_make_request(align_bi);
3922 return 1;
3923 } else {
3924 rcu_read_unlock();
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08003925 bio_put(align_bi);
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003926 return 0;
3927 }
3928}
3929
Dan Williams8b3e6cd2008-04-28 02:15:53 -07003930/* __get_priority_stripe - get the next stripe to process
3931 *
3932 * Full stripe writes are allowed to pass preread active stripes up until
3933 * the bypass_threshold is exceeded. In general the bypass_count
3934 * increments when the handle_list is handled before the hold_list; however, it
3935 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
3936 * stripe with in flight i/o. The bypass_count will be reset when the
3937 * head of the hold_list has changed, i.e. the head was promoted to the
3938 * handle_list.
3939 */
3940static struct stripe_head *__get_priority_stripe(raid5_conf_t *conf)
3941{
3942 struct stripe_head *sh;
3943
3944 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
3945 __func__,
3946 list_empty(&conf->handle_list) ? "empty" : "busy",
3947 list_empty(&conf->hold_list) ? "empty" : "busy",
3948 atomic_read(&conf->pending_full_writes), conf->bypass_count);
3949
3950 if (!list_empty(&conf->handle_list)) {
3951 sh = list_entry(conf->handle_list.next, typeof(*sh), lru);
3952
3953 if (list_empty(&conf->hold_list))
3954 conf->bypass_count = 0;
3955 else if (!test_bit(STRIPE_IO_STARTED, &sh->state)) {
3956 if (conf->hold_list.next == conf->last_hold)
3957 conf->bypass_count++;
3958 else {
3959 conf->last_hold = conf->hold_list.next;
3960 conf->bypass_count -= conf->bypass_threshold;
3961 if (conf->bypass_count < 0)
3962 conf->bypass_count = 0;
3963 }
3964 }
3965 } else if (!list_empty(&conf->hold_list) &&
3966 ((conf->bypass_threshold &&
3967 conf->bypass_count > conf->bypass_threshold) ||
3968 atomic_read(&conf->pending_full_writes) == 0)) {
3969 sh = list_entry(conf->hold_list.next,
3970 typeof(*sh), lru);
3971 conf->bypass_count -= conf->bypass_threshold;
3972 if (conf->bypass_count < 0)
3973 conf->bypass_count = 0;
3974 } else
3975 return NULL;
3976
3977 list_del_init(&sh->lru);
3978 atomic_inc(&sh->count);
3979 BUG_ON(atomic_read(&sh->count) != 1);
3980 return sh;
3981}
Raz Ben-Jehuda(caro)f6796232006-12-10 02:20:46 -08003982
NeilBrown21a52c62010-04-01 15:02:13 +11003983static int make_request(mddev_t *mddev, struct bio * bi)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003984{
NeilBrown070ec552009-06-16 16:54:21 +10003985 raid5_conf_t *conf = mddev->private;
NeilBrown911d4ee2009-03-31 14:39:38 +11003986 int dd_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003987 sector_t new_sector;
3988 sector_t logical_sector, last_sector;
3989 struct stripe_head *sh;
Jens Axboea3623572005-11-01 09:26:16 +01003990 const int rw = bio_data_dir(bi);
NeilBrown49077322010-03-25 16:20:56 +11003991 int remaining;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003992
Tejun Heoe9c74692010-09-03 11:56:18 +02003993 if (unlikely(bi->bi_rw & REQ_FLUSH)) {
3994 md_flush_request(mddev, bi);
NeilBrowne5dcdd82005-09-09 16:23:41 -07003995 return 0;
3996 }
3997
NeilBrown3d310eb2005-06-21 17:17:26 -07003998 md_write_start(mddev, bi);
NeilBrown06d91a52005-06-21 17:17:12 -07003999
NeilBrown802ba062006-12-13 00:34:13 -08004000 if (rw == READ &&
Raz Ben-Jehuda(caro)52488612006-12-10 02:20:48 -08004001 mddev->reshape_position == MaxSector &&
NeilBrown21a52c62010-04-01 15:02:13 +11004002 chunk_aligned_read(mddev,bi))
NeilBrown99c0fb52009-03-31 14:39:38 +11004003 return 0;
Raz Ben-Jehuda(caro)52488612006-12-10 02:20:48 -08004004
Linus Torvalds1da177e2005-04-16 15:20:36 -07004005 logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1);
4006 last_sector = bi->bi_sector + (bi->bi_size>>9);
4007 bi->bi_next = NULL;
4008 bi->bi_phys_segments = 1; /* over-loaded to count active stripes */
NeilBrown06d91a52005-06-21 17:17:12 -07004009
Linus Torvalds1da177e2005-04-16 15:20:36 -07004010 for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) {
4011 DEFINE_WAIT(w);
NeilBrown16a53ec2006-06-26 00:27:38 -07004012 int disks, data_disks;
NeilBrownb5663ba2009-03-31 14:39:38 +11004013 int previous;
NeilBrownb578d552006-03-27 01:18:12 -08004014
NeilBrown7ecaa1e2006-03-27 01:18:08 -08004015 retry:
NeilBrownb5663ba2009-03-31 14:39:38 +11004016 previous = 0;
NeilBrownb0f9ec02009-03-31 15:27:18 +11004017 disks = conf->raid_disks;
NeilBrownb578d552006-03-27 01:18:12 -08004018 prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE);
NeilBrownb0f9ec02009-03-31 15:27:18 +11004019 if (unlikely(conf->reshape_progress != MaxSector)) {
NeilBrownfef9c612009-03-31 15:16:46 +11004020 /* spinlock is needed as reshape_progress may be
NeilBrowndf8e7f72006-03-27 01:18:15 -08004021 * 64bit on a 32bit platform, and so it might be
4022 * possible to see a half-updated value
NeilBrownfef9c612009-03-31 15:16:46 +11004023 * Ofcourse reshape_progress could change after
NeilBrowndf8e7f72006-03-27 01:18:15 -08004024 * the lock is dropped, so once we get a reference
4025 * to the stripe that we think it is, we will have
4026 * to check again.
4027 */
NeilBrown7ecaa1e2006-03-27 01:18:08 -08004028 spin_lock_irq(&conf->device_lock);
NeilBrownfef9c612009-03-31 15:16:46 +11004029 if (mddev->delta_disks < 0
4030 ? logical_sector < conf->reshape_progress
4031 : logical_sector >= conf->reshape_progress) {
NeilBrown7ecaa1e2006-03-27 01:18:08 -08004032 disks = conf->previous_raid_disks;
NeilBrownb5663ba2009-03-31 14:39:38 +11004033 previous = 1;
4034 } else {
NeilBrownfef9c612009-03-31 15:16:46 +11004035 if (mddev->delta_disks < 0
4036 ? logical_sector < conf->reshape_safe
4037 : logical_sector >= conf->reshape_safe) {
NeilBrownb578d552006-03-27 01:18:12 -08004038 spin_unlock_irq(&conf->device_lock);
4039 schedule();
4040 goto retry;
4041 }
4042 }
NeilBrown7ecaa1e2006-03-27 01:18:08 -08004043 spin_unlock_irq(&conf->device_lock);
4044 }
NeilBrown16a53ec2006-06-26 00:27:38 -07004045 data_disks = disks - conf->max_degraded;
4046
NeilBrown112bf892009-03-31 14:39:38 +11004047 new_sector = raid5_compute_sector(conf, logical_sector,
4048 previous,
NeilBrown911d4ee2009-03-31 14:39:38 +11004049 &dd_idx, NULL);
NeilBrown0c55e022010-05-03 14:09:02 +10004050 pr_debug("raid456: make_request, sector %llu logical %llu\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07004051 (unsigned long long)new_sector,
4052 (unsigned long long)logical_sector);
4053
NeilBrownb5663ba2009-03-31 14:39:38 +11004054 sh = get_active_stripe(conf, new_sector, previous,
NeilBrowna8c906c2009-06-09 14:39:59 +10004055 (bi->bi_rw&RWA_MASK), 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004056 if (sh) {
NeilBrownb0f9ec02009-03-31 15:27:18 +11004057 if (unlikely(previous)) {
NeilBrown7ecaa1e2006-03-27 01:18:08 -08004058 /* expansion might have moved on while waiting for a
NeilBrowndf8e7f72006-03-27 01:18:15 -08004059 * stripe, so we must do the range check again.
4060 * Expansion could still move past after this
4061 * test, but as we are holding a reference to
4062 * 'sh', we know that if that happens,
4063 * STRIPE_EXPANDING will get set and the expansion
4064 * won't proceed until we finish with the stripe.
NeilBrown7ecaa1e2006-03-27 01:18:08 -08004065 */
4066 int must_retry = 0;
4067 spin_lock_irq(&conf->device_lock);
NeilBrownb0f9ec02009-03-31 15:27:18 +11004068 if (mddev->delta_disks < 0
4069 ? logical_sector >= conf->reshape_progress
4070 : logical_sector < conf->reshape_progress)
NeilBrown7ecaa1e2006-03-27 01:18:08 -08004071 /* mismatch, need to try again */
4072 must_retry = 1;
4073 spin_unlock_irq(&conf->device_lock);
4074 if (must_retry) {
4075 release_stripe(sh);
Dan Williams7a3ab902009-06-16 16:00:33 -07004076 schedule();
NeilBrown7ecaa1e2006-03-27 01:18:08 -08004077 goto retry;
4078 }
4079 }
NeilBrowne62e58a2009-07-01 13:15:35 +10004080
NeilBrowna5c308d2009-07-01 13:15:35 +10004081 if (bio_data_dir(bi) == WRITE &&
4082 logical_sector >= mddev->suspend_lo &&
NeilBrowne464eaf2006-03-27 01:18:14 -08004083 logical_sector < mddev->suspend_hi) {
4084 release_stripe(sh);
NeilBrowne62e58a2009-07-01 13:15:35 +10004085 /* As the suspend_* range is controlled by
4086 * userspace, we want an interruptible
4087 * wait.
4088 */
4089 flush_signals(current);
4090 prepare_to_wait(&conf->wait_for_overlap,
4091 &w, TASK_INTERRUPTIBLE);
4092 if (logical_sector >= mddev->suspend_lo &&
4093 logical_sector < mddev->suspend_hi)
4094 schedule();
NeilBrowne464eaf2006-03-27 01:18:14 -08004095 goto retry;
4096 }
NeilBrown7ecaa1e2006-03-27 01:18:08 -08004097
4098 if (test_bit(STRIPE_EXPANDING, &sh->state) ||
4099 !add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) {
4100 /* Stripe is busy expanding or
4101 * add failed due to overlap. Flush everything
Linus Torvalds1da177e2005-04-16 15:20:36 -07004102 * and wait a while
4103 */
NeilBrown9f7c2222010-07-26 12:04:13 +10004104 md_raid5_unplug_device(conf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004105 release_stripe(sh);
4106 schedule();
4107 goto retry;
4108 }
4109 finish_wait(&conf->wait_for_overlap, &w);
NeilBrown6ed30032008-02-06 01:40:00 -08004110 set_bit(STRIPE_HANDLE, &sh->state);
4111 clear_bit(STRIPE_DELAYED, &sh->state);
Tejun Heoe9c74692010-09-03 11:56:18 +02004112 if ((bi->bi_rw & REQ_SYNC) &&
NeilBrown729a1862009-12-14 12:49:50 +11004113 !test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
4114 atomic_inc(&conf->preread_active_stripes);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004115 release_stripe(sh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004116 } else {
4117 /* cannot get stripe for read-ahead, just give-up */
4118 clear_bit(BIO_UPTODATE, &bi->bi_flags);
4119 finish_wait(&conf->wait_for_overlap, &w);
4120 break;
4121 }
4122
4123 }
4124 spin_lock_irq(&conf->device_lock);
Jens Axboe960e7392008-08-15 10:41:18 +02004125 remaining = raid5_dec_bi_phys_segments(bi);
NeilBrownf6344752006-03-27 01:18:17 -08004126 spin_unlock_irq(&conf->device_lock);
4127 if (remaining == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004128
NeilBrown16a53ec2006-06-26 00:27:38 -07004129 if ( rw == WRITE )
Linus Torvalds1da177e2005-04-16 15:20:36 -07004130 md_write_end(mddev);
NeilBrown6712ecf2007-09-27 12:47:43 +02004131
Neil Brown0e13fe232008-06-28 08:31:20 +10004132 bio_endio(bi, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004133 }
NeilBrown729a1862009-12-14 12:49:50 +11004134
Linus Torvalds1da177e2005-04-16 15:20:36 -07004135 return 0;
4136}
4137
Dan Williamsb522adc2009-03-31 15:00:31 +11004138static sector_t raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks);
4139
NeilBrown52c03292006-06-26 00:27:43 -07004140static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004141{
NeilBrown52c03292006-06-26 00:27:43 -07004142 /* reshaping is quite different to recovery/resync so it is
4143 * handled quite separately ... here.
4144 *
4145 * On each call to sync_request, we gather one chunk worth of
4146 * destination stripes and flag them as expanding.
4147 * Then we find all the source stripes and request reads.
4148 * As the reads complete, handle_stripe will copy the data
4149 * into the destination stripe and release that stripe.
4150 */
H Hartley Sweeten7b928132010-03-08 16:02:40 +11004151 raid5_conf_t *conf = mddev->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004152 struct stripe_head *sh;
NeilBrownccfcc3c2006-03-27 01:18:09 -08004153 sector_t first_sector, last_sector;
NeilBrownf4168852007-02-28 20:11:53 -08004154 int raid_disks = conf->previous_raid_disks;
4155 int data_disks = raid_disks - conf->max_degraded;
4156 int new_data_disks = conf->raid_disks - conf->max_degraded;
NeilBrown52c03292006-06-26 00:27:43 -07004157 int i;
4158 int dd_idx;
NeilBrownc8f517c2009-03-31 15:28:40 +11004159 sector_t writepos, readpos, safepos;
NeilBrownec32a2b2009-03-31 15:17:38 +11004160 sector_t stripe_addr;
NeilBrown7a661382009-03-31 15:21:40 +11004161 int reshape_sectors;
NeilBrownab69ae12009-03-31 15:26:47 +11004162 struct list_head stripes;
NeilBrown52c03292006-06-26 00:27:43 -07004163
NeilBrownfef9c612009-03-31 15:16:46 +11004164 if (sector_nr == 0) {
4165 /* If restarting in the middle, skip the initial sectors */
4166 if (mddev->delta_disks < 0 &&
4167 conf->reshape_progress < raid5_size(mddev, 0, 0)) {
4168 sector_nr = raid5_size(mddev, 0, 0)
4169 - conf->reshape_progress;
NeilBrowna6397552009-08-13 10:13:00 +10004170 } else if (mddev->delta_disks >= 0 &&
NeilBrownfef9c612009-03-31 15:16:46 +11004171 conf->reshape_progress > 0)
4172 sector_nr = conf->reshape_progress;
NeilBrownf4168852007-02-28 20:11:53 -08004173 sector_div(sector_nr, new_data_disks);
NeilBrownfef9c612009-03-31 15:16:46 +11004174 if (sector_nr) {
NeilBrown8dee7212009-11-06 14:59:29 +11004175 mddev->curr_resync_completed = sector_nr;
4176 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
NeilBrownfef9c612009-03-31 15:16:46 +11004177 *skipped = 1;
4178 return sector_nr;
4179 }
NeilBrown52c03292006-06-26 00:27:43 -07004180 }
4181
NeilBrown7a661382009-03-31 15:21:40 +11004182 /* We need to process a full chunk at a time.
4183 * If old and new chunk sizes differ, we need to process the
4184 * largest of these
4185 */
Andre Noll664e7c42009-06-18 08:45:27 +10004186 if (mddev->new_chunk_sectors > mddev->chunk_sectors)
4187 reshape_sectors = mddev->new_chunk_sectors;
NeilBrown7a661382009-03-31 15:21:40 +11004188 else
Andre Noll9d8f0362009-06-18 08:45:01 +10004189 reshape_sectors = mddev->chunk_sectors;
NeilBrown7a661382009-03-31 15:21:40 +11004190
NeilBrown52c03292006-06-26 00:27:43 -07004191 /* we update the metadata when there is more than 3Meg
4192 * in the block range (that is rather arbitrary, should
4193 * probably be time based) or when the data about to be
4194 * copied would over-write the source of the data at
4195 * the front of the range.
NeilBrownfef9c612009-03-31 15:16:46 +11004196 * i.e. one new_stripe along from reshape_progress new_maps
4197 * to after where reshape_safe old_maps to
NeilBrown52c03292006-06-26 00:27:43 -07004198 */
NeilBrownfef9c612009-03-31 15:16:46 +11004199 writepos = conf->reshape_progress;
NeilBrownf4168852007-02-28 20:11:53 -08004200 sector_div(writepos, new_data_disks);
NeilBrownc8f517c2009-03-31 15:28:40 +11004201 readpos = conf->reshape_progress;
4202 sector_div(readpos, data_disks);
NeilBrownfef9c612009-03-31 15:16:46 +11004203 safepos = conf->reshape_safe;
NeilBrownf4168852007-02-28 20:11:53 -08004204 sector_div(safepos, data_disks);
NeilBrownfef9c612009-03-31 15:16:46 +11004205 if (mddev->delta_disks < 0) {
NeilBrowned37d832009-05-27 21:39:05 +10004206 writepos -= min_t(sector_t, reshape_sectors, writepos);
NeilBrownc8f517c2009-03-31 15:28:40 +11004207 readpos += reshape_sectors;
NeilBrown7a661382009-03-31 15:21:40 +11004208 safepos += reshape_sectors;
NeilBrownfef9c612009-03-31 15:16:46 +11004209 } else {
NeilBrown7a661382009-03-31 15:21:40 +11004210 writepos += reshape_sectors;
NeilBrowned37d832009-05-27 21:39:05 +10004211 readpos -= min_t(sector_t, reshape_sectors, readpos);
4212 safepos -= min_t(sector_t, reshape_sectors, safepos);
NeilBrownfef9c612009-03-31 15:16:46 +11004213 }
NeilBrown52c03292006-06-26 00:27:43 -07004214
NeilBrownc8f517c2009-03-31 15:28:40 +11004215 /* 'writepos' is the most advanced device address we might write.
4216 * 'readpos' is the least advanced device address we might read.
4217 * 'safepos' is the least address recorded in the metadata as having
4218 * been reshaped.
4219 * If 'readpos' is behind 'writepos', then there is no way that we can
4220 * ensure safety in the face of a crash - that must be done by userspace
4221 * making a backup of the data. So in that case there is no particular
4222 * rush to update metadata.
4223 * Otherwise if 'safepos' is behind 'writepos', then we really need to
4224 * update the metadata to advance 'safepos' to match 'readpos' so that
4225 * we can be safe in the event of a crash.
4226 * So we insist on updating metadata if safepos is behind writepos and
4227 * readpos is beyond writepos.
4228 * In any case, update the metadata every 10 seconds.
4229 * Maybe that number should be configurable, but I'm not sure it is
4230 * worth it.... maybe it could be a multiple of safemode_delay???
4231 */
NeilBrownfef9c612009-03-31 15:16:46 +11004232 if ((mddev->delta_disks < 0
NeilBrownc8f517c2009-03-31 15:28:40 +11004233 ? (safepos > writepos && readpos < writepos)
4234 : (safepos < writepos && readpos > writepos)) ||
4235 time_after(jiffies, conf->reshape_checkpoint + 10*HZ)) {
NeilBrown52c03292006-06-26 00:27:43 -07004236 /* Cannot proceed until we've updated the superblock... */
4237 wait_event(conf->wait_for_overlap,
4238 atomic_read(&conf->reshape_stripes)==0);
NeilBrownfef9c612009-03-31 15:16:46 +11004239 mddev->reshape_position = conf->reshape_progress;
NeilBrownacb180b2009-04-14 16:28:34 +10004240 mddev->curr_resync_completed = mddev->curr_resync;
NeilBrownc8f517c2009-03-31 15:28:40 +11004241 conf->reshape_checkpoint = jiffies;
NeilBrown850b2b42006-10-03 01:15:46 -07004242 set_bit(MD_CHANGE_DEVS, &mddev->flags);
NeilBrown52c03292006-06-26 00:27:43 -07004243 md_wakeup_thread(mddev->thread);
NeilBrown850b2b42006-10-03 01:15:46 -07004244 wait_event(mddev->sb_wait, mddev->flags == 0 ||
NeilBrown52c03292006-06-26 00:27:43 -07004245 kthread_should_stop());
4246 spin_lock_irq(&conf->device_lock);
NeilBrownfef9c612009-03-31 15:16:46 +11004247 conf->reshape_safe = mddev->reshape_position;
NeilBrown52c03292006-06-26 00:27:43 -07004248 spin_unlock_irq(&conf->device_lock);
4249 wake_up(&conf->wait_for_overlap);
NeilBrownacb180b2009-04-14 16:28:34 +10004250 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
NeilBrown52c03292006-06-26 00:27:43 -07004251 }
4252
NeilBrownec32a2b2009-03-31 15:17:38 +11004253 if (mddev->delta_disks < 0) {
4254 BUG_ON(conf->reshape_progress == 0);
4255 stripe_addr = writepos;
4256 BUG_ON((mddev->dev_sectors &
NeilBrown7a661382009-03-31 15:21:40 +11004257 ~((sector_t)reshape_sectors - 1))
4258 - reshape_sectors - stripe_addr
NeilBrownec32a2b2009-03-31 15:17:38 +11004259 != sector_nr);
4260 } else {
NeilBrown7a661382009-03-31 15:21:40 +11004261 BUG_ON(writepos != sector_nr + reshape_sectors);
NeilBrownec32a2b2009-03-31 15:17:38 +11004262 stripe_addr = sector_nr;
4263 }
NeilBrownab69ae12009-03-31 15:26:47 +11004264 INIT_LIST_HEAD(&stripes);
NeilBrown7a661382009-03-31 15:21:40 +11004265 for (i = 0; i < reshape_sectors; i += STRIPE_SECTORS) {
NeilBrown52c03292006-06-26 00:27:43 -07004266 int j;
NeilBrowna9f326e2009-09-23 18:06:41 +10004267 int skipped_disk = 0;
NeilBrowna8c906c2009-06-09 14:39:59 +10004268 sh = get_active_stripe(conf, stripe_addr+i, 0, 0, 1);
NeilBrown52c03292006-06-26 00:27:43 -07004269 set_bit(STRIPE_EXPANDING, &sh->state);
4270 atomic_inc(&conf->reshape_stripes);
4271 /* If any of this stripe is beyond the end of the old
4272 * array, then we need to zero those blocks
4273 */
4274 for (j=sh->disks; j--;) {
4275 sector_t s;
4276 if (j == sh->pd_idx)
4277 continue;
NeilBrownf4168852007-02-28 20:11:53 -08004278 if (conf->level == 6 &&
NeilBrownd0dabf72009-03-31 14:39:38 +11004279 j == sh->qd_idx)
NeilBrownf4168852007-02-28 20:11:53 -08004280 continue;
NeilBrown784052e2009-03-31 15:19:07 +11004281 s = compute_blocknr(sh, j, 0);
Dan Williamsb522adc2009-03-31 15:00:31 +11004282 if (s < raid5_size(mddev, 0, 0)) {
NeilBrowna9f326e2009-09-23 18:06:41 +10004283 skipped_disk = 1;
NeilBrown52c03292006-06-26 00:27:43 -07004284 continue;
4285 }
4286 memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE);
4287 set_bit(R5_Expanded, &sh->dev[j].flags);
4288 set_bit(R5_UPTODATE, &sh->dev[j].flags);
4289 }
NeilBrowna9f326e2009-09-23 18:06:41 +10004290 if (!skipped_disk) {
NeilBrown52c03292006-06-26 00:27:43 -07004291 set_bit(STRIPE_EXPAND_READY, &sh->state);
4292 set_bit(STRIPE_HANDLE, &sh->state);
4293 }
NeilBrownab69ae12009-03-31 15:26:47 +11004294 list_add(&sh->lru, &stripes);
NeilBrown52c03292006-06-26 00:27:43 -07004295 }
4296 spin_lock_irq(&conf->device_lock);
NeilBrownfef9c612009-03-31 15:16:46 +11004297 if (mddev->delta_disks < 0)
NeilBrown7a661382009-03-31 15:21:40 +11004298 conf->reshape_progress -= reshape_sectors * new_data_disks;
NeilBrownfef9c612009-03-31 15:16:46 +11004299 else
NeilBrown7a661382009-03-31 15:21:40 +11004300 conf->reshape_progress += reshape_sectors * new_data_disks;
NeilBrown52c03292006-06-26 00:27:43 -07004301 spin_unlock_irq(&conf->device_lock);
4302 /* Ok, those stripe are ready. We can start scheduling
4303 * reads on the source stripes.
4304 * The source stripes are determined by mapping the first and last
4305 * block on the destination stripes.
4306 */
NeilBrown52c03292006-06-26 00:27:43 -07004307 first_sector =
NeilBrownec32a2b2009-03-31 15:17:38 +11004308 raid5_compute_sector(conf, stripe_addr*(new_data_disks),
NeilBrown911d4ee2009-03-31 14:39:38 +11004309 1, &dd_idx, NULL);
NeilBrown52c03292006-06-26 00:27:43 -07004310 last_sector =
NeilBrown0e6e0272009-06-09 16:32:22 +10004311 raid5_compute_sector(conf, ((stripe_addr+reshape_sectors)
Andre Noll09c9e5f2009-06-18 08:45:55 +10004312 * new_data_disks - 1),
NeilBrown911d4ee2009-03-31 14:39:38 +11004313 1, &dd_idx, NULL);
Andre Noll58c0fed2009-03-31 14:33:13 +11004314 if (last_sector >= mddev->dev_sectors)
4315 last_sector = mddev->dev_sectors - 1;
NeilBrown52c03292006-06-26 00:27:43 -07004316 while (first_sector <= last_sector) {
NeilBrowna8c906c2009-06-09 14:39:59 +10004317 sh = get_active_stripe(conf, first_sector, 1, 0, 1);
NeilBrown52c03292006-06-26 00:27:43 -07004318 set_bit(STRIPE_EXPAND_SOURCE, &sh->state);
4319 set_bit(STRIPE_HANDLE, &sh->state);
4320 release_stripe(sh);
4321 first_sector += STRIPE_SECTORS;
4322 }
NeilBrownab69ae12009-03-31 15:26:47 +11004323 /* Now that the sources are clearly marked, we can release
4324 * the destination stripes
4325 */
4326 while (!list_empty(&stripes)) {
4327 sh = list_entry(stripes.next, struct stripe_head, lru);
4328 list_del_init(&sh->lru);
4329 release_stripe(sh);
4330 }
NeilBrownc6207272008-02-06 01:39:52 -08004331 /* If this takes us to the resync_max point where we have to pause,
4332 * then we need to write out the superblock.
4333 */
NeilBrown7a661382009-03-31 15:21:40 +11004334 sector_nr += reshape_sectors;
NeilBrownc03f6a12009-04-17 11:06:30 +10004335 if ((sector_nr - mddev->curr_resync_completed) * 2
4336 >= mddev->resync_max - mddev->curr_resync_completed) {
NeilBrownc6207272008-02-06 01:39:52 -08004337 /* Cannot proceed until we've updated the superblock... */
4338 wait_event(conf->wait_for_overlap,
4339 atomic_read(&conf->reshape_stripes) == 0);
NeilBrownfef9c612009-03-31 15:16:46 +11004340 mddev->reshape_position = conf->reshape_progress;
NeilBrown48606a92009-06-18 09:14:12 +10004341 mddev->curr_resync_completed = mddev->curr_resync + reshape_sectors;
NeilBrownc8f517c2009-03-31 15:28:40 +11004342 conf->reshape_checkpoint = jiffies;
NeilBrownc6207272008-02-06 01:39:52 -08004343 set_bit(MD_CHANGE_DEVS, &mddev->flags);
4344 md_wakeup_thread(mddev->thread);
4345 wait_event(mddev->sb_wait,
4346 !test_bit(MD_CHANGE_DEVS, &mddev->flags)
4347 || kthread_should_stop());
4348 spin_lock_irq(&conf->device_lock);
NeilBrownfef9c612009-03-31 15:16:46 +11004349 conf->reshape_safe = mddev->reshape_position;
NeilBrownc6207272008-02-06 01:39:52 -08004350 spin_unlock_irq(&conf->device_lock);
4351 wake_up(&conf->wait_for_overlap);
NeilBrownacb180b2009-04-14 16:28:34 +10004352 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
NeilBrownc6207272008-02-06 01:39:52 -08004353 }
NeilBrown7a661382009-03-31 15:21:40 +11004354 return reshape_sectors;
NeilBrown52c03292006-06-26 00:27:43 -07004355}
4356
4357/* FIXME go_faster isn't used */
4358static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster)
4359{
H Hartley Sweeten7b928132010-03-08 16:02:40 +11004360 raid5_conf_t *conf = mddev->private;
NeilBrown52c03292006-06-26 00:27:43 -07004361 struct stripe_head *sh;
Andre Noll58c0fed2009-03-31 14:33:13 +11004362 sector_t max_sector = mddev->dev_sectors;
NeilBrown72626682005-09-09 16:23:54 -07004363 int sync_blocks;
NeilBrown16a53ec2006-06-26 00:27:38 -07004364 int still_degraded = 0;
4365 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004366
NeilBrown72626682005-09-09 16:23:54 -07004367 if (sector_nr >= max_sector) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004368 /* just being told to finish up .. nothing much to do */
4369 unplug_slaves(mddev);
NeilBrowncea9c222009-03-31 15:15:05 +11004370
NeilBrown29269552006-03-27 01:18:10 -08004371 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) {
4372 end_reshape(conf);
4373 return 0;
4374 }
NeilBrown72626682005-09-09 16:23:54 -07004375
4376 if (mddev->curr_resync < max_sector) /* aborted */
4377 bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
4378 &sync_blocks, 1);
NeilBrown16a53ec2006-06-26 00:27:38 -07004379 else /* completed sync */
NeilBrown72626682005-09-09 16:23:54 -07004380 conf->fullsync = 0;
4381 bitmap_close_sync(mddev->bitmap);
4382
Linus Torvalds1da177e2005-04-16 15:20:36 -07004383 return 0;
4384 }
NeilBrownccfcc3c2006-03-27 01:18:09 -08004385
NeilBrown64bd6602009-08-03 10:59:58 +10004386 /* Allow raid5_quiesce to complete */
4387 wait_event(conf->wait_for_overlap, conf->quiesce != 2);
4388
NeilBrown52c03292006-06-26 00:27:43 -07004389 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
4390 return reshape_request(mddev, sector_nr, skipped);
NeilBrownf6705572006-03-27 01:18:11 -08004391
NeilBrownc6207272008-02-06 01:39:52 -08004392 /* No need to check resync_max as we never do more than one
4393 * stripe, and as resync_max will always be on a chunk boundary,
4394 * if the check in md_do_sync didn't fire, there is no chance
4395 * of overstepping resync_max here
4396 */
4397
NeilBrown16a53ec2006-06-26 00:27:38 -07004398 /* if there is too many failed drives and we are trying
Linus Torvalds1da177e2005-04-16 15:20:36 -07004399 * to resync, then assert that we are finished, because there is
4400 * nothing we can do.
4401 */
NeilBrown3285edf2006-06-26 00:27:55 -07004402 if (mddev->degraded >= conf->max_degraded &&
NeilBrown16a53ec2006-06-26 00:27:38 -07004403 test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
Andre Noll58c0fed2009-03-31 14:33:13 +11004404 sector_t rv = mddev->dev_sectors - sector_nr;
NeilBrown57afd892005-06-21 17:17:13 -07004405 *skipped = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004406 return rv;
4407 }
NeilBrown72626682005-09-09 16:23:54 -07004408 if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
NeilBrown3855ad92005-11-08 21:39:38 -08004409 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
NeilBrown72626682005-09-09 16:23:54 -07004410 !conf->fullsync && sync_blocks >= STRIPE_SECTORS) {
4411 /* we can skip this block, and probably more */
4412 sync_blocks /= STRIPE_SECTORS;
4413 *skipped = 1;
4414 return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */
4415 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07004416
NeilBrownb47490c2008-02-06 01:39:50 -08004417
4418 bitmap_cond_end_sync(mddev->bitmap, sector_nr);
4419
NeilBrowna8c906c2009-06-09 14:39:59 +10004420 sh = get_active_stripe(conf, sector_nr, 0, 1, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004421 if (sh == NULL) {
NeilBrowna8c906c2009-06-09 14:39:59 +10004422 sh = get_active_stripe(conf, sector_nr, 0, 0, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004423 /* make sure we don't swamp the stripe cache if someone else
NeilBrown16a53ec2006-06-26 00:27:38 -07004424 * is trying to get access
Linus Torvalds1da177e2005-04-16 15:20:36 -07004425 */
Nishanth Aravamudan66c006a2005-11-07 01:01:17 -08004426 schedule_timeout_uninterruptible(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004427 }
NeilBrown16a53ec2006-06-26 00:27:38 -07004428 /* Need to check if array will still be degraded after recovery/resync
4429 * We don't need to check the 'failed' flag as when that gets set,
4430 * recovery aborts.
4431 */
NeilBrownf001a702009-06-09 14:30:31 +10004432 for (i = 0; i < conf->raid_disks; i++)
NeilBrown16a53ec2006-06-26 00:27:38 -07004433 if (conf->disks[i].rdev == NULL)
4434 still_degraded = 1;
4435
4436 bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded);
4437
4438 spin_lock(&sh->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004439 set_bit(STRIPE_SYNCING, &sh->state);
4440 clear_bit(STRIPE_INSYNC, &sh->state);
4441 spin_unlock(&sh->lock);
4442
NeilBrown14425772009-10-16 15:55:25 +11004443 handle_stripe(sh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004444 release_stripe(sh);
4445
4446 return STRIPE_SECTORS;
4447}
4448
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004449static int retry_aligned_read(raid5_conf_t *conf, struct bio *raid_bio)
4450{
4451 /* We may not be able to submit a whole bio at once as there
4452 * may not be enough stripe_heads available.
4453 * We cannot pre-allocate enough stripe_heads as we may need
4454 * more than exist in the cache (if we allow ever large chunks).
4455 * So we do one stripe head at a time and record in
4456 * ->bi_hw_segments how many have been done.
4457 *
4458 * We *know* that this entire raid_bio is in one chunk, so
4459 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
4460 */
4461 struct stripe_head *sh;
NeilBrown911d4ee2009-03-31 14:39:38 +11004462 int dd_idx;
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004463 sector_t sector, logical_sector, last_sector;
4464 int scnt = 0;
4465 int remaining;
4466 int handled = 0;
4467
4468 logical_sector = raid_bio->bi_sector & ~((sector_t)STRIPE_SECTORS-1);
NeilBrown112bf892009-03-31 14:39:38 +11004469 sector = raid5_compute_sector(conf, logical_sector,
NeilBrown911d4ee2009-03-31 14:39:38 +11004470 0, &dd_idx, NULL);
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004471 last_sector = raid_bio->bi_sector + (raid_bio->bi_size>>9);
4472
4473 for (; logical_sector < last_sector;
Neil Brown387bb172007-02-08 14:20:29 -08004474 logical_sector += STRIPE_SECTORS,
4475 sector += STRIPE_SECTORS,
4476 scnt++) {
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004477
Jens Axboe960e7392008-08-15 10:41:18 +02004478 if (scnt < raid5_bi_hw_segments(raid_bio))
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004479 /* already done this stripe */
4480 continue;
4481
NeilBrowna8c906c2009-06-09 14:39:59 +10004482 sh = get_active_stripe(conf, sector, 0, 1, 0);
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004483
4484 if (!sh) {
4485 /* failed to get a stripe - must wait */
Jens Axboe960e7392008-08-15 10:41:18 +02004486 raid5_set_bi_hw_segments(raid_bio, scnt);
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004487 conf->retry_read_aligned = raid_bio;
4488 return handled;
4489 }
4490
4491 set_bit(R5_ReadError, &sh->dev[dd_idx].flags);
Neil Brown387bb172007-02-08 14:20:29 -08004492 if (!add_stripe_bio(sh, raid_bio, dd_idx, 0)) {
4493 release_stripe(sh);
Jens Axboe960e7392008-08-15 10:41:18 +02004494 raid5_set_bi_hw_segments(raid_bio, scnt);
Neil Brown387bb172007-02-08 14:20:29 -08004495 conf->retry_read_aligned = raid_bio;
4496 return handled;
4497 }
4498
Dan Williams36d1c642009-07-14 11:48:22 -07004499 handle_stripe(sh);
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004500 release_stripe(sh);
4501 handled++;
4502 }
4503 spin_lock_irq(&conf->device_lock);
Jens Axboe960e7392008-08-15 10:41:18 +02004504 remaining = raid5_dec_bi_phys_segments(raid_bio);
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004505 spin_unlock_irq(&conf->device_lock);
Neil Brown0e13fe232008-06-28 08:31:20 +10004506 if (remaining == 0)
4507 bio_endio(raid_bio, 0);
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004508 if (atomic_dec_and_test(&conf->active_aligned_reads))
4509 wake_up(&conf->wait_for_stripe);
4510 return handled;
4511}
4512
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004513
Linus Torvalds1da177e2005-04-16 15:20:36 -07004514/*
4515 * This is our raid5 kernel thread.
4516 *
4517 * We scan the hash table for stripes which can be handled now.
4518 * During the scan, completed stripes are saved for us by the interrupt
4519 * handler, so that they will not have to wait for our next wakeup.
4520 */
NeilBrown6ed30032008-02-06 01:40:00 -08004521static void raid5d(mddev_t *mddev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004522{
4523 struct stripe_head *sh;
NeilBrown070ec552009-06-16 16:54:21 +10004524 raid5_conf_t *conf = mddev->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004525 int handled;
4526
Dan Williams45b42332007-07-09 11:56:43 -07004527 pr_debug("+++ raid5d active\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07004528
4529 md_check_recovery(mddev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004530
4531 handled = 0;
4532 spin_lock_irq(&conf->device_lock);
4533 while (1) {
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004534 struct bio *bio;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004535
NeilBrownae3c20c2006-07-10 04:44:17 -07004536 if (conf->seq_flush != conf->seq_write) {
NeilBrown72626682005-09-09 16:23:54 -07004537 int seq = conf->seq_flush;
NeilBrown700e4322005-11-28 13:44:10 -08004538 spin_unlock_irq(&conf->device_lock);
NeilBrown72626682005-09-09 16:23:54 -07004539 bitmap_unplug(mddev->bitmap);
NeilBrown700e4322005-11-28 13:44:10 -08004540 spin_lock_irq(&conf->device_lock);
NeilBrown72626682005-09-09 16:23:54 -07004541 conf->seq_write = seq;
4542 activate_bit_delay(conf);
4543 }
4544
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08004545 while ((bio = remove_bio_from_retry(conf))) {
4546 int ok;
4547 spin_unlock_irq(&conf->device_lock);
4548 ok = retry_aligned_read(conf, bio);
4549 spin_lock_irq(&conf->device_lock);
4550 if (!ok)
4551 break;
4552 handled++;
4553 }
4554
Dan Williams8b3e6cd2008-04-28 02:15:53 -07004555 sh = __get_priority_stripe(conf);
4556
Dan Williamsc9f21aa2008-07-23 12:05:51 -07004557 if (!sh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004558 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004559 spin_unlock_irq(&conf->device_lock);
4560
4561 handled++;
Dan Williams417b8d42009-10-16 16:25:22 +11004562 handle_stripe(sh);
4563 release_stripe(sh);
4564 cond_resched();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004565
4566 spin_lock_irq(&conf->device_lock);
4567 }
Dan Williams45b42332007-07-09 11:56:43 -07004568 pr_debug("%d stripes handled\n", handled);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004569
4570 spin_unlock_irq(&conf->device_lock);
4571
Dan Williamsc9f21aa2008-07-23 12:05:51 -07004572 async_tx_issue_pending_all();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004573 unplug_slaves(mddev);
4574
Dan Williams45b42332007-07-09 11:56:43 -07004575 pr_debug("--- raid5d inactive\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07004576}
4577
NeilBrown3f294f42005-11-08 21:39:25 -08004578static ssize_t
NeilBrown007583c2005-11-08 21:39:30 -08004579raid5_show_stripe_cache_size(mddev_t *mddev, char *page)
NeilBrown3f294f42005-11-08 21:39:25 -08004580{
NeilBrown070ec552009-06-16 16:54:21 +10004581 raid5_conf_t *conf = mddev->private;
NeilBrown96de1e62005-11-08 21:39:39 -08004582 if (conf)
4583 return sprintf(page, "%d\n", conf->max_nr_stripes);
4584 else
4585 return 0;
NeilBrown3f294f42005-11-08 21:39:25 -08004586}
4587
NeilBrownc41d4ac2010-06-01 19:37:24 +10004588int
4589raid5_set_cache_size(mddev_t *mddev, int size)
4590{
4591 raid5_conf_t *conf = mddev->private;
4592 int err;
4593
4594 if (size <= 16 || size > 32768)
4595 return -EINVAL;
4596 while (size < conf->max_nr_stripes) {
4597 if (drop_one_stripe(conf))
4598 conf->max_nr_stripes--;
4599 else
4600 break;
4601 }
4602 err = md_allow_write(mddev);
4603 if (err)
4604 return err;
4605 while (size > conf->max_nr_stripes) {
4606 if (grow_one_stripe(conf))
4607 conf->max_nr_stripes++;
4608 else break;
4609 }
4610 return 0;
4611}
4612EXPORT_SYMBOL(raid5_set_cache_size);
4613
NeilBrown3f294f42005-11-08 21:39:25 -08004614static ssize_t
NeilBrown007583c2005-11-08 21:39:30 -08004615raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len)
NeilBrown3f294f42005-11-08 21:39:25 -08004616{
NeilBrown070ec552009-06-16 16:54:21 +10004617 raid5_conf_t *conf = mddev->private;
Dan Williams4ef197d82008-04-28 02:15:54 -07004618 unsigned long new;
Dan Williamsb5470dc2008-06-27 21:44:04 -07004619 int err;
4620
NeilBrown3f294f42005-11-08 21:39:25 -08004621 if (len >= PAGE_SIZE)
4622 return -EINVAL;
NeilBrown96de1e62005-11-08 21:39:39 -08004623 if (!conf)
4624 return -ENODEV;
NeilBrown3f294f42005-11-08 21:39:25 -08004625
Dan Williams4ef197d82008-04-28 02:15:54 -07004626 if (strict_strtoul(page, 10, &new))
NeilBrown3f294f42005-11-08 21:39:25 -08004627 return -EINVAL;
NeilBrownc41d4ac2010-06-01 19:37:24 +10004628 err = raid5_set_cache_size(mddev, new);
Dan Williamsb5470dc2008-06-27 21:44:04 -07004629 if (err)
4630 return err;
NeilBrown3f294f42005-11-08 21:39:25 -08004631 return len;
4632}
NeilBrown007583c2005-11-08 21:39:30 -08004633
NeilBrown96de1e62005-11-08 21:39:39 -08004634static struct md_sysfs_entry
4635raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR,
4636 raid5_show_stripe_cache_size,
4637 raid5_store_stripe_cache_size);
NeilBrown3f294f42005-11-08 21:39:25 -08004638
4639static ssize_t
Dan Williams8b3e6cd2008-04-28 02:15:53 -07004640raid5_show_preread_threshold(mddev_t *mddev, char *page)
4641{
NeilBrown070ec552009-06-16 16:54:21 +10004642 raid5_conf_t *conf = mddev->private;
Dan Williams8b3e6cd2008-04-28 02:15:53 -07004643 if (conf)
4644 return sprintf(page, "%d\n", conf->bypass_threshold);
4645 else
4646 return 0;
4647}
4648
4649static ssize_t
4650raid5_store_preread_threshold(mddev_t *mddev, const char *page, size_t len)
4651{
NeilBrown070ec552009-06-16 16:54:21 +10004652 raid5_conf_t *conf = mddev->private;
Dan Williams4ef197d82008-04-28 02:15:54 -07004653 unsigned long new;
Dan Williams8b3e6cd2008-04-28 02:15:53 -07004654 if (len >= PAGE_SIZE)
4655 return -EINVAL;
4656 if (!conf)
4657 return -ENODEV;
4658
Dan Williams4ef197d82008-04-28 02:15:54 -07004659 if (strict_strtoul(page, 10, &new))
Dan Williams8b3e6cd2008-04-28 02:15:53 -07004660 return -EINVAL;
Dan Williams4ef197d82008-04-28 02:15:54 -07004661 if (new > conf->max_nr_stripes)
Dan Williams8b3e6cd2008-04-28 02:15:53 -07004662 return -EINVAL;
4663 conf->bypass_threshold = new;
4664 return len;
4665}
4666
4667static struct md_sysfs_entry
4668raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold,
4669 S_IRUGO | S_IWUSR,
4670 raid5_show_preread_threshold,
4671 raid5_store_preread_threshold);
4672
4673static ssize_t
NeilBrown96de1e62005-11-08 21:39:39 -08004674stripe_cache_active_show(mddev_t *mddev, char *page)
NeilBrown3f294f42005-11-08 21:39:25 -08004675{
NeilBrown070ec552009-06-16 16:54:21 +10004676 raid5_conf_t *conf = mddev->private;
NeilBrown96de1e62005-11-08 21:39:39 -08004677 if (conf)
4678 return sprintf(page, "%d\n", atomic_read(&conf->active_stripes));
4679 else
4680 return 0;
NeilBrown3f294f42005-11-08 21:39:25 -08004681}
4682
NeilBrown96de1e62005-11-08 21:39:39 -08004683static struct md_sysfs_entry
4684raid5_stripecache_active = __ATTR_RO(stripe_cache_active);
NeilBrown3f294f42005-11-08 21:39:25 -08004685
NeilBrown007583c2005-11-08 21:39:30 -08004686static struct attribute *raid5_attrs[] = {
NeilBrown3f294f42005-11-08 21:39:25 -08004687 &raid5_stripecache_size.attr,
4688 &raid5_stripecache_active.attr,
Dan Williams8b3e6cd2008-04-28 02:15:53 -07004689 &raid5_preread_bypass_threshold.attr,
NeilBrown3f294f42005-11-08 21:39:25 -08004690 NULL,
4691};
NeilBrown007583c2005-11-08 21:39:30 -08004692static struct attribute_group raid5_attrs_group = {
4693 .name = NULL,
4694 .attrs = raid5_attrs,
NeilBrown3f294f42005-11-08 21:39:25 -08004695};
4696
Dan Williams80c3a6c2009-03-17 18:10:40 -07004697static sector_t
4698raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks)
4699{
NeilBrown070ec552009-06-16 16:54:21 +10004700 raid5_conf_t *conf = mddev->private;
Dan Williams80c3a6c2009-03-17 18:10:40 -07004701
4702 if (!sectors)
4703 sectors = mddev->dev_sectors;
NeilBrown5e5e3e72009-10-16 16:35:30 +11004704 if (!raid_disks)
NeilBrown7ec05472009-03-31 15:10:36 +11004705 /* size is defined by the smallest of previous and new size */
NeilBrown5e5e3e72009-10-16 16:35:30 +11004706 raid_disks = min(conf->raid_disks, conf->previous_raid_disks);
Dan Williams80c3a6c2009-03-17 18:10:40 -07004707
Andre Noll9d8f0362009-06-18 08:45:01 +10004708 sectors &= ~((sector_t)mddev->chunk_sectors - 1);
Andre Noll664e7c42009-06-18 08:45:27 +10004709 sectors &= ~((sector_t)mddev->new_chunk_sectors - 1);
Dan Williams80c3a6c2009-03-17 18:10:40 -07004710 return sectors * (raid_disks - conf->max_degraded);
4711}
4712
Dan Williams36d1c642009-07-14 11:48:22 -07004713static void raid5_free_percpu(raid5_conf_t *conf)
4714{
4715 struct raid5_percpu *percpu;
4716 unsigned long cpu;
4717
4718 if (!conf->percpu)
4719 return;
4720
4721 get_online_cpus();
4722 for_each_possible_cpu(cpu) {
4723 percpu = per_cpu_ptr(conf->percpu, cpu);
4724 safe_put_page(percpu->spare_page);
Dan Williamsd6f38f32009-07-14 11:50:52 -07004725 kfree(percpu->scribble);
Dan Williams36d1c642009-07-14 11:48:22 -07004726 }
4727#ifdef CONFIG_HOTPLUG_CPU
4728 unregister_cpu_notifier(&conf->cpu_notify);
4729#endif
4730 put_online_cpus();
4731
4732 free_percpu(conf->percpu);
4733}
4734
Dan Williams95fc17a2009-07-31 12:39:15 +10004735static void free_conf(raid5_conf_t *conf)
4736{
4737 shrink_stripes(conf);
Dan Williams36d1c642009-07-14 11:48:22 -07004738 raid5_free_percpu(conf);
Dan Williams95fc17a2009-07-31 12:39:15 +10004739 kfree(conf->disks);
4740 kfree(conf->stripe_hashtbl);
4741 kfree(conf);
4742}
4743
Dan Williams36d1c642009-07-14 11:48:22 -07004744#ifdef CONFIG_HOTPLUG_CPU
4745static int raid456_cpu_notify(struct notifier_block *nfb, unsigned long action,
4746 void *hcpu)
4747{
4748 raid5_conf_t *conf = container_of(nfb, raid5_conf_t, cpu_notify);
4749 long cpu = (long)hcpu;
4750 struct raid5_percpu *percpu = per_cpu_ptr(conf->percpu, cpu);
4751
4752 switch (action) {
4753 case CPU_UP_PREPARE:
4754 case CPU_UP_PREPARE_FROZEN:
Dan Williamsd6f38f32009-07-14 11:50:52 -07004755 if (conf->level == 6 && !percpu->spare_page)
Dan Williams36d1c642009-07-14 11:48:22 -07004756 percpu->spare_page = alloc_page(GFP_KERNEL);
Dan Williamsd6f38f32009-07-14 11:50:52 -07004757 if (!percpu->scribble)
4758 percpu->scribble = kmalloc(conf->scribble_len, GFP_KERNEL);
4759
4760 if (!percpu->scribble ||
4761 (conf->level == 6 && !percpu->spare_page)) {
4762 safe_put_page(percpu->spare_page);
4763 kfree(percpu->scribble);
Dan Williams36d1c642009-07-14 11:48:22 -07004764 pr_err("%s: failed memory allocation for cpu%ld\n",
4765 __func__, cpu);
Akinobu Mita55af6bb2010-05-26 14:43:35 -07004766 return notifier_from_errno(-ENOMEM);
Dan Williams36d1c642009-07-14 11:48:22 -07004767 }
4768 break;
4769 case CPU_DEAD:
4770 case CPU_DEAD_FROZEN:
4771 safe_put_page(percpu->spare_page);
Dan Williamsd6f38f32009-07-14 11:50:52 -07004772 kfree(percpu->scribble);
Dan Williams36d1c642009-07-14 11:48:22 -07004773 percpu->spare_page = NULL;
Dan Williamsd6f38f32009-07-14 11:50:52 -07004774 percpu->scribble = NULL;
Dan Williams36d1c642009-07-14 11:48:22 -07004775 break;
4776 default:
4777 break;
4778 }
4779 return NOTIFY_OK;
4780}
4781#endif
4782
4783static int raid5_alloc_percpu(raid5_conf_t *conf)
4784{
4785 unsigned long cpu;
4786 struct page *spare_page;
Tejun Heoa29d8b82010-02-02 14:39:15 +09004787 struct raid5_percpu __percpu *allcpus;
Dan Williamsd6f38f32009-07-14 11:50:52 -07004788 void *scribble;
Dan Williams36d1c642009-07-14 11:48:22 -07004789 int err;
4790
Dan Williams36d1c642009-07-14 11:48:22 -07004791 allcpus = alloc_percpu(struct raid5_percpu);
4792 if (!allcpus)
4793 return -ENOMEM;
4794 conf->percpu = allcpus;
4795
4796 get_online_cpus();
4797 err = 0;
4798 for_each_present_cpu(cpu) {
Dan Williamsd6f38f32009-07-14 11:50:52 -07004799 if (conf->level == 6) {
4800 spare_page = alloc_page(GFP_KERNEL);
4801 if (!spare_page) {
4802 err = -ENOMEM;
4803 break;
4804 }
4805 per_cpu_ptr(conf->percpu, cpu)->spare_page = spare_page;
4806 }
NeilBrown5e5e3e72009-10-16 16:35:30 +11004807 scribble = kmalloc(conf->scribble_len, GFP_KERNEL);
Dan Williamsd6f38f32009-07-14 11:50:52 -07004808 if (!scribble) {
Dan Williams36d1c642009-07-14 11:48:22 -07004809 err = -ENOMEM;
4810 break;
4811 }
Dan Williamsd6f38f32009-07-14 11:50:52 -07004812 per_cpu_ptr(conf->percpu, cpu)->scribble = scribble;
Dan Williams36d1c642009-07-14 11:48:22 -07004813 }
4814#ifdef CONFIG_HOTPLUG_CPU
4815 conf->cpu_notify.notifier_call = raid456_cpu_notify;
4816 conf->cpu_notify.priority = 0;
4817 if (err == 0)
4818 err = register_cpu_notifier(&conf->cpu_notify);
4819#endif
4820 put_online_cpus();
4821
4822 return err;
4823}
4824
NeilBrown91adb562009-03-31 14:39:39 +11004825static raid5_conf_t *setup_conf(mddev_t *mddev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004826{
4827 raid5_conf_t *conf;
NeilBrown5e5e3e72009-10-16 16:35:30 +11004828 int raid_disk, memory, max_disks;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004829 mdk_rdev_t *rdev;
4830 struct disk_info *disk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004831
NeilBrown91adb562009-03-31 14:39:39 +11004832 if (mddev->new_level != 5
4833 && mddev->new_level != 4
4834 && mddev->new_level != 6) {
NeilBrown0c55e022010-05-03 14:09:02 +10004835 printk(KERN_ERR "md/raid:%s: raid level not set to 4/5/6 (%d)\n",
NeilBrown91adb562009-03-31 14:39:39 +11004836 mdname(mddev), mddev->new_level);
4837 return ERR_PTR(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004838 }
NeilBrown91adb562009-03-31 14:39:39 +11004839 if ((mddev->new_level == 5
4840 && !algorithm_valid_raid5(mddev->new_layout)) ||
4841 (mddev->new_level == 6
4842 && !algorithm_valid_raid6(mddev->new_layout))) {
NeilBrown0c55e022010-05-03 14:09:02 +10004843 printk(KERN_ERR "md/raid:%s: layout %d not supported\n",
NeilBrown91adb562009-03-31 14:39:39 +11004844 mdname(mddev), mddev->new_layout);
4845 return ERR_PTR(-EIO);
4846 }
4847 if (mddev->new_level == 6 && mddev->raid_disks < 4) {
NeilBrown0c55e022010-05-03 14:09:02 +10004848 printk(KERN_ERR "md/raid:%s: not enough configured devices (%d, minimum 4)\n",
NeilBrown91adb562009-03-31 14:39:39 +11004849 mdname(mddev), mddev->raid_disks);
4850 return ERR_PTR(-EINVAL);
NeilBrown99c0fb52009-03-31 14:39:38 +11004851 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07004852
Andre Noll664e7c42009-06-18 08:45:27 +10004853 if (!mddev->new_chunk_sectors ||
4854 (mddev->new_chunk_sectors << 9) % PAGE_SIZE ||
4855 !is_power_of_2(mddev->new_chunk_sectors)) {
NeilBrown0c55e022010-05-03 14:09:02 +10004856 printk(KERN_ERR "md/raid:%s: invalid chunk size %d\n",
4857 mdname(mddev), mddev->new_chunk_sectors << 9);
NeilBrown91adb562009-03-31 14:39:39 +11004858 return ERR_PTR(-EINVAL);
NeilBrown4bbf3772008-10-13 11:55:12 +11004859 }
4860
NeilBrown91adb562009-03-31 14:39:39 +11004861 conf = kzalloc(sizeof(raid5_conf_t), GFP_KERNEL);
4862 if (conf == NULL)
4863 goto abort;
Dan Williamsf5efd452009-10-16 15:55:38 +11004864 spin_lock_init(&conf->device_lock);
4865 init_waitqueue_head(&conf->wait_for_stripe);
4866 init_waitqueue_head(&conf->wait_for_overlap);
4867 INIT_LIST_HEAD(&conf->handle_list);
4868 INIT_LIST_HEAD(&conf->hold_list);
4869 INIT_LIST_HEAD(&conf->delayed_list);
4870 INIT_LIST_HEAD(&conf->bitmap_list);
4871 INIT_LIST_HEAD(&conf->inactive_list);
4872 atomic_set(&conf->active_stripes, 0);
4873 atomic_set(&conf->preread_active_stripes, 0);
4874 atomic_set(&conf->active_aligned_reads, 0);
4875 conf->bypass_threshold = BYPASS_THRESHOLD;
NeilBrown91adb562009-03-31 14:39:39 +11004876
4877 conf->raid_disks = mddev->raid_disks;
4878 if (mddev->reshape_position == MaxSector)
4879 conf->previous_raid_disks = mddev->raid_disks;
4880 else
4881 conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks;
NeilBrown5e5e3e72009-10-16 16:35:30 +11004882 max_disks = max(conf->raid_disks, conf->previous_raid_disks);
4883 conf->scribble_len = scribble_len(max_disks);
NeilBrown91adb562009-03-31 14:39:39 +11004884
NeilBrown5e5e3e72009-10-16 16:35:30 +11004885 conf->disks = kzalloc(max_disks * sizeof(struct disk_info),
NeilBrown91adb562009-03-31 14:39:39 +11004886 GFP_KERNEL);
4887 if (!conf->disks)
4888 goto abort;
4889
4890 conf->mddev = mddev;
4891
4892 if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL)
4893 goto abort;
4894
Dan Williams36d1c642009-07-14 11:48:22 -07004895 conf->level = mddev->new_level;
4896 if (raid5_alloc_percpu(conf) != 0)
4897 goto abort;
4898
NeilBrown0c55e022010-05-03 14:09:02 +10004899 pr_debug("raid456: run(%s) called.\n", mdname(mddev));
NeilBrown91adb562009-03-31 14:39:39 +11004900
4901 list_for_each_entry(rdev, &mddev->disks, same_set) {
4902 raid_disk = rdev->raid_disk;
NeilBrown5e5e3e72009-10-16 16:35:30 +11004903 if (raid_disk >= max_disks
NeilBrown91adb562009-03-31 14:39:39 +11004904 || raid_disk < 0)
4905 continue;
4906 disk = conf->disks + raid_disk;
4907
4908 disk->rdev = rdev;
4909
4910 if (test_bit(In_sync, &rdev->flags)) {
4911 char b[BDEVNAME_SIZE];
NeilBrown0c55e022010-05-03 14:09:02 +10004912 printk(KERN_INFO "md/raid:%s: device %s operational as raid"
4913 " disk %d\n",
4914 mdname(mddev), bdevname(rdev->bdev, b), raid_disk);
NeilBrown91adb562009-03-31 14:39:39 +11004915 } else
4916 /* Cannot rely on bitmap to complete recovery */
4917 conf->fullsync = 1;
4918 }
4919
Andre Noll09c9e5f2009-06-18 08:45:55 +10004920 conf->chunk_sectors = mddev->new_chunk_sectors;
NeilBrown91adb562009-03-31 14:39:39 +11004921 conf->level = mddev->new_level;
4922 if (conf->level == 6)
4923 conf->max_degraded = 2;
4924 else
4925 conf->max_degraded = 1;
4926 conf->algorithm = mddev->new_layout;
4927 conf->max_nr_stripes = NR_STRIPES;
NeilBrownfef9c612009-03-31 15:16:46 +11004928 conf->reshape_progress = mddev->reshape_position;
NeilBrowne183eae2009-03-31 15:20:22 +11004929 if (conf->reshape_progress != MaxSector) {
Andre Noll09c9e5f2009-06-18 08:45:55 +10004930 conf->prev_chunk_sectors = mddev->chunk_sectors;
NeilBrowne183eae2009-03-31 15:20:22 +11004931 conf->prev_algo = mddev->layout;
4932 }
NeilBrown91adb562009-03-31 14:39:39 +11004933
4934 memory = conf->max_nr_stripes * (sizeof(struct stripe_head) +
NeilBrown5e5e3e72009-10-16 16:35:30 +11004935 max_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024;
NeilBrown91adb562009-03-31 14:39:39 +11004936 if (grow_stripes(conf, conf->max_nr_stripes)) {
4937 printk(KERN_ERR
NeilBrown0c55e022010-05-03 14:09:02 +10004938 "md/raid:%s: couldn't allocate %dkB for buffers\n",
4939 mdname(mddev), memory);
NeilBrown91adb562009-03-31 14:39:39 +11004940 goto abort;
4941 } else
NeilBrown0c55e022010-05-03 14:09:02 +10004942 printk(KERN_INFO "md/raid:%s: allocated %dkB\n",
4943 mdname(mddev), memory);
NeilBrown91adb562009-03-31 14:39:39 +11004944
NeilBrown0da3c612009-09-23 18:09:45 +10004945 conf->thread = md_register_thread(raid5d, mddev, NULL);
NeilBrown91adb562009-03-31 14:39:39 +11004946 if (!conf->thread) {
4947 printk(KERN_ERR
NeilBrown0c55e022010-05-03 14:09:02 +10004948 "md/raid:%s: couldn't allocate thread.\n",
NeilBrown91adb562009-03-31 14:39:39 +11004949 mdname(mddev));
4950 goto abort;
4951 }
4952
4953 return conf;
4954
4955 abort:
4956 if (conf) {
Dan Williams95fc17a2009-07-31 12:39:15 +10004957 free_conf(conf);
NeilBrown91adb562009-03-31 14:39:39 +11004958 return ERR_PTR(-EIO);
4959 } else
4960 return ERR_PTR(-ENOMEM);
4961}
4962
NeilBrownc148ffd2009-11-13 17:47:00 +11004963
4964static int only_parity(int raid_disk, int algo, int raid_disks, int max_degraded)
4965{
4966 switch (algo) {
4967 case ALGORITHM_PARITY_0:
4968 if (raid_disk < max_degraded)
4969 return 1;
4970 break;
4971 case ALGORITHM_PARITY_N:
4972 if (raid_disk >= raid_disks - max_degraded)
4973 return 1;
4974 break;
4975 case ALGORITHM_PARITY_0_6:
4976 if (raid_disk == 0 ||
4977 raid_disk == raid_disks - 1)
4978 return 1;
4979 break;
4980 case ALGORITHM_LEFT_ASYMMETRIC_6:
4981 case ALGORITHM_RIGHT_ASYMMETRIC_6:
4982 case ALGORITHM_LEFT_SYMMETRIC_6:
4983 case ALGORITHM_RIGHT_SYMMETRIC_6:
4984 if (raid_disk == raid_disks - 1)
4985 return 1;
4986 }
4987 return 0;
4988}
4989
NeilBrown91adb562009-03-31 14:39:39 +11004990static int run(mddev_t *mddev)
4991{
4992 raid5_conf_t *conf;
NeilBrown9f7c2222010-07-26 12:04:13 +10004993 int working_disks = 0;
NeilBrownc148ffd2009-11-13 17:47:00 +11004994 int dirty_parity_disks = 0;
NeilBrown91adb562009-03-31 14:39:39 +11004995 mdk_rdev_t *rdev;
NeilBrownc148ffd2009-11-13 17:47:00 +11004996 sector_t reshape_offset = 0;
NeilBrown91adb562009-03-31 14:39:39 +11004997
Andre Noll8c6ac862009-06-18 08:48:06 +10004998 if (mddev->recovery_cp != MaxSector)
NeilBrown0c55e022010-05-03 14:09:02 +10004999 printk(KERN_NOTICE "md/raid:%s: not clean"
Andre Noll8c6ac862009-06-18 08:48:06 +10005000 " -- starting background reconstruction\n",
5001 mdname(mddev));
NeilBrownf6705572006-03-27 01:18:11 -08005002 if (mddev->reshape_position != MaxSector) {
5003 /* Check that we can continue the reshape.
5004 * Currently only disks can change, it must
5005 * increase, and we must be past the point where
5006 * a stripe over-writes itself
5007 */
5008 sector_t here_new, here_old;
5009 int old_disks;
Andre Noll18b00332009-03-31 15:00:56 +11005010 int max_degraded = (mddev->level == 6 ? 2 : 1);
NeilBrownf6705572006-03-27 01:18:11 -08005011
NeilBrown88ce4932009-03-31 15:24:23 +11005012 if (mddev->new_level != mddev->level) {
NeilBrown0c55e022010-05-03 14:09:02 +10005013 printk(KERN_ERR "md/raid:%s: unsupported reshape "
NeilBrownf4168852007-02-28 20:11:53 -08005014 "required - aborting.\n",
NeilBrownf6705572006-03-27 01:18:11 -08005015 mdname(mddev));
5016 return -EINVAL;
5017 }
NeilBrownf6705572006-03-27 01:18:11 -08005018 old_disks = mddev->raid_disks - mddev->delta_disks;
5019 /* reshape_position must be on a new-stripe boundary, and one
NeilBrownf4168852007-02-28 20:11:53 -08005020 * further up in new geometry must map after here in old
5021 * geometry.
NeilBrownf6705572006-03-27 01:18:11 -08005022 */
5023 here_new = mddev->reshape_position;
Andre Noll664e7c42009-06-18 08:45:27 +10005024 if (sector_div(here_new, mddev->new_chunk_sectors *
NeilBrownf4168852007-02-28 20:11:53 -08005025 (mddev->raid_disks - max_degraded))) {
NeilBrown0c55e022010-05-03 14:09:02 +10005026 printk(KERN_ERR "md/raid:%s: reshape_position not "
5027 "on a stripe boundary\n", mdname(mddev));
NeilBrownf6705572006-03-27 01:18:11 -08005028 return -EINVAL;
5029 }
NeilBrownc148ffd2009-11-13 17:47:00 +11005030 reshape_offset = here_new * mddev->new_chunk_sectors;
NeilBrownf6705572006-03-27 01:18:11 -08005031 /* here_new is the stripe we will write to */
5032 here_old = mddev->reshape_position;
Andre Noll9d8f0362009-06-18 08:45:01 +10005033 sector_div(here_old, mddev->chunk_sectors *
NeilBrownf4168852007-02-28 20:11:53 -08005034 (old_disks-max_degraded));
5035 /* here_old is the first stripe that we might need to read
5036 * from */
NeilBrown67ac6012009-08-13 10:06:24 +10005037 if (mddev->delta_disks == 0) {
5038 /* We cannot be sure it is safe to start an in-place
5039 * reshape. It is only safe if user-space if monitoring
5040 * and taking constant backups.
5041 * mdadm always starts a situation like this in
5042 * readonly mode so it can take control before
5043 * allowing any writes. So just check for that.
5044 */
5045 if ((here_new * mddev->new_chunk_sectors !=
5046 here_old * mddev->chunk_sectors) ||
5047 mddev->ro == 0) {
NeilBrown0c55e022010-05-03 14:09:02 +10005048 printk(KERN_ERR "md/raid:%s: in-place reshape must be started"
5049 " in read-only mode - aborting\n",
5050 mdname(mddev));
NeilBrown67ac6012009-08-13 10:06:24 +10005051 return -EINVAL;
5052 }
5053 } else if (mddev->delta_disks < 0
5054 ? (here_new * mddev->new_chunk_sectors <=
5055 here_old * mddev->chunk_sectors)
5056 : (here_new * mddev->new_chunk_sectors >=
5057 here_old * mddev->chunk_sectors)) {
NeilBrownf6705572006-03-27 01:18:11 -08005058 /* Reading from the same stripe as writing to - bad */
NeilBrown0c55e022010-05-03 14:09:02 +10005059 printk(KERN_ERR "md/raid:%s: reshape_position too early for "
5060 "auto-recovery - aborting.\n",
5061 mdname(mddev));
NeilBrownf6705572006-03-27 01:18:11 -08005062 return -EINVAL;
5063 }
NeilBrown0c55e022010-05-03 14:09:02 +10005064 printk(KERN_INFO "md/raid:%s: reshape will continue\n",
5065 mdname(mddev));
NeilBrownf6705572006-03-27 01:18:11 -08005066 /* OK, we should be able to continue; */
NeilBrownf6705572006-03-27 01:18:11 -08005067 } else {
NeilBrown91adb562009-03-31 14:39:39 +11005068 BUG_ON(mddev->level != mddev->new_level);
5069 BUG_ON(mddev->layout != mddev->new_layout);
Andre Noll664e7c42009-06-18 08:45:27 +10005070 BUG_ON(mddev->chunk_sectors != mddev->new_chunk_sectors);
NeilBrown91adb562009-03-31 14:39:39 +11005071 BUG_ON(mddev->delta_disks != 0);
NeilBrownf6705572006-03-27 01:18:11 -08005072 }
5073
NeilBrown245f46c2009-03-31 14:39:39 +11005074 if (mddev->private == NULL)
5075 conf = setup_conf(mddev);
5076 else
5077 conf = mddev->private;
5078
NeilBrown91adb562009-03-31 14:39:39 +11005079 if (IS_ERR(conf))
5080 return PTR_ERR(conf);
NeilBrown9ffae0c2006-01-06 00:20:32 -08005081
NeilBrown91adb562009-03-31 14:39:39 +11005082 mddev->thread = conf->thread;
5083 conf->thread = NULL;
5084 mddev->private = conf;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005085
Linus Torvalds1da177e2005-04-16 15:20:36 -07005086 /*
NeilBrown16a53ec2006-06-26 00:27:38 -07005087 * 0 for a fully functional array, 1 or 2 for a degraded array.
Linus Torvalds1da177e2005-04-16 15:20:36 -07005088 */
NeilBrownc148ffd2009-11-13 17:47:00 +11005089 list_for_each_entry(rdev, &mddev->disks, same_set) {
5090 if (rdev->raid_disk < 0)
5091 continue;
NeilBrown2f115882010-06-17 17:41:03 +10005092 if (test_bit(In_sync, &rdev->flags)) {
NeilBrown91adb562009-03-31 14:39:39 +11005093 working_disks++;
NeilBrown2f115882010-06-17 17:41:03 +10005094 continue;
5095 }
NeilBrownc148ffd2009-11-13 17:47:00 +11005096 /* This disc is not fully in-sync. However if it
5097 * just stored parity (beyond the recovery_offset),
5098 * when we don't need to be concerned about the
5099 * array being dirty.
5100 * When reshape goes 'backwards', we never have
5101 * partially completed devices, so we only need
5102 * to worry about reshape going forwards.
5103 */
5104 /* Hack because v0.91 doesn't store recovery_offset properly. */
5105 if (mddev->major_version == 0 &&
5106 mddev->minor_version > 90)
5107 rdev->recovery_offset = reshape_offset;
5108
NeilBrownc148ffd2009-11-13 17:47:00 +11005109 if (rdev->recovery_offset < reshape_offset) {
5110 /* We need to check old and new layout */
5111 if (!only_parity(rdev->raid_disk,
5112 conf->algorithm,
5113 conf->raid_disks,
5114 conf->max_degraded))
5115 continue;
5116 }
5117 if (!only_parity(rdev->raid_disk,
5118 conf->prev_algo,
5119 conf->previous_raid_disks,
5120 conf->max_degraded))
5121 continue;
5122 dirty_parity_disks++;
5123 }
NeilBrown91adb562009-03-31 14:39:39 +11005124
NeilBrown5e5e3e72009-10-16 16:35:30 +11005125 mddev->degraded = (max(conf->raid_disks, conf->previous_raid_disks)
5126 - working_disks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005127
NeilBrown674806d2010-06-16 17:17:53 +10005128 if (has_failed(conf)) {
NeilBrown0c55e022010-05-03 14:09:02 +10005129 printk(KERN_ERR "md/raid:%s: not enough operational devices"
Linus Torvalds1da177e2005-04-16 15:20:36 -07005130 " (%d/%d failed)\n",
NeilBrown02c2de82006-10-03 01:15:47 -07005131 mdname(mddev), mddev->degraded, conf->raid_disks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005132 goto abort;
5133 }
5134
NeilBrown91adb562009-03-31 14:39:39 +11005135 /* device size must be a multiple of chunk size */
Andre Noll9d8f0362009-06-18 08:45:01 +10005136 mddev->dev_sectors &= ~(mddev->chunk_sectors - 1);
NeilBrown91adb562009-03-31 14:39:39 +11005137 mddev->resync_max_sectors = mddev->dev_sectors;
5138
NeilBrownc148ffd2009-11-13 17:47:00 +11005139 if (mddev->degraded > dirty_parity_disks &&
Linus Torvalds1da177e2005-04-16 15:20:36 -07005140 mddev->recovery_cp != MaxSector) {
NeilBrown6ff8d8e2006-01-06 00:20:15 -08005141 if (mddev->ok_start_degraded)
5142 printk(KERN_WARNING
NeilBrown0c55e022010-05-03 14:09:02 +10005143 "md/raid:%s: starting dirty degraded array"
5144 " - data corruption possible.\n",
NeilBrown6ff8d8e2006-01-06 00:20:15 -08005145 mdname(mddev));
5146 else {
5147 printk(KERN_ERR
NeilBrown0c55e022010-05-03 14:09:02 +10005148 "md/raid:%s: cannot start dirty degraded array.\n",
NeilBrown6ff8d8e2006-01-06 00:20:15 -08005149 mdname(mddev));
5150 goto abort;
5151 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07005152 }
5153
Linus Torvalds1da177e2005-04-16 15:20:36 -07005154 if (mddev->degraded == 0)
NeilBrown0c55e022010-05-03 14:09:02 +10005155 printk(KERN_INFO "md/raid:%s: raid level %d active with %d out of %d"
5156 " devices, algorithm %d\n", mdname(mddev), conf->level,
NeilBrowne183eae2009-03-31 15:20:22 +11005157 mddev->raid_disks-mddev->degraded, mddev->raid_disks,
5158 mddev->new_layout);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005159 else
NeilBrown0c55e022010-05-03 14:09:02 +10005160 printk(KERN_ALERT "md/raid:%s: raid level %d active with %d"
5161 " out of %d devices, algorithm %d\n",
5162 mdname(mddev), conf->level,
5163 mddev->raid_disks - mddev->degraded,
5164 mddev->raid_disks, mddev->new_layout);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005165
5166 print_raid5_conf(conf);
5167
NeilBrownfef9c612009-03-31 15:16:46 +11005168 if (conf->reshape_progress != MaxSector) {
NeilBrownfef9c612009-03-31 15:16:46 +11005169 conf->reshape_safe = conf->reshape_progress;
NeilBrownf6705572006-03-27 01:18:11 -08005170 atomic_set(&conf->reshape_stripes, 0);
5171 clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
5172 clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
5173 set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
5174 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
5175 mddev->sync_thread = md_register_thread(md_do_sync, mddev,
NeilBrown0da3c612009-09-23 18:09:45 +10005176 "reshape");
NeilBrownf6705572006-03-27 01:18:11 -08005177 }
5178
Linus Torvalds1da177e2005-04-16 15:20:36 -07005179
5180 /* Ok, everything is just fine now */
NeilBrowna64c8762010-04-14 17:15:37 +10005181 if (mddev->to_remove == &raid5_attrs_group)
5182 mddev->to_remove = NULL;
NeilBrown00bcb4a2010-06-01 19:37:23 +10005183 else if (mddev->kobj.sd &&
5184 sysfs_create_group(&mddev->kobj, &raid5_attrs_group))
NeilBrown5e55e2f2007-03-26 21:32:14 -08005185 printk(KERN_WARNING
NeilBrown4a5add42010-06-01 19:37:28 +10005186 "raid5: failed to create sysfs attributes for %s\n",
NeilBrown5e55e2f2007-03-26 21:32:14 -08005187 mdname(mddev));
NeilBrown4a5add42010-06-01 19:37:28 +10005188 md_set_array_sectors(mddev, raid5_size(mddev, 0, 0));
5189
NeilBrown2ac87402010-06-01 19:37:29 +10005190 plugger_init(&conf->plug, raid5_unplug);
NeilBrown252ac522010-06-01 19:37:29 +10005191 mddev->plug = &conf->plug;
NeilBrown4a5add42010-06-01 19:37:28 +10005192 if (mddev->queue) {
NeilBrown9f7c2222010-07-26 12:04:13 +10005193 int chunk_size;
NeilBrown4a5add42010-06-01 19:37:28 +10005194 /* read-ahead size must cover two whole stripes, which
5195 * is 2 * (datadisks) * chunksize where 'n' is the
5196 * number of raid devices
5197 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07005198 int data_disks = conf->previous_raid_disks - conf->max_degraded;
5199 int stripe = data_disks *
5200 ((mddev->chunk_sectors << 9) / PAGE_SIZE);
5201 if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe)
5202 mddev->queue->backing_dev_info.ra_pages = 2 * stripe;
NeilBrown4a5add42010-06-01 19:37:28 +10005203
5204 blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec);
NeilBrown11d8a6e2010-07-26 11:57:07 +10005205
5206 mddev->queue->backing_dev_info.congested_data = mddev;
5207 mddev->queue->backing_dev_info.congested_fn = raid5_congested;
NeilBrown9f7c2222010-07-26 12:04:13 +10005208 mddev->queue->queue_lock = &conf->device_lock;
5209 mddev->queue->unplug_fn = raid5_unplug_queue;
5210
5211 chunk_size = mddev->chunk_sectors << 9;
5212 blk_queue_io_min(mddev->queue, chunk_size);
5213 blk_queue_io_opt(mddev->queue, chunk_size *
5214 (conf->raid_disks - conf->max_degraded));
5215
5216 list_for_each_entry(rdev, &mddev->disks, same_set)
5217 disk_stack_limits(mddev->gendisk, rdev->bdev,
5218 rdev->data_offset << 9);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005219 }
5220
Linus Torvalds1da177e2005-04-16 15:20:36 -07005221 return 0;
5222abort:
NeilBrowne0cf8f02009-03-31 14:39:39 +11005223 md_unregister_thread(mddev->thread);
NeilBrown91adb562009-03-31 14:39:39 +11005224 mddev->thread = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005225 if (conf) {
5226 print_raid5_conf(conf);
Dan Williams95fc17a2009-07-31 12:39:15 +10005227 free_conf(conf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005228 }
5229 mddev->private = NULL;
NeilBrown0c55e022010-05-03 14:09:02 +10005230 printk(KERN_ALERT "md/raid:%s: failed to run raid set.\n", mdname(mddev));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005231 return -EIO;
5232}
5233
NeilBrown3f294f42005-11-08 21:39:25 -08005234static int stop(mddev_t *mddev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07005235{
H Hartley Sweeten7b928132010-03-08 16:02:40 +11005236 raid5_conf_t *conf = mddev->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005237
5238 md_unregister_thread(mddev->thread);
5239 mddev->thread = NULL;
NeilBrown11d8a6e2010-07-26 11:57:07 +10005240 if (mddev->queue)
5241 mddev->queue->backing_dev_info.congested_fn = NULL;
NeilBrown2ac87402010-06-01 19:37:29 +10005242 plugger_flush(&conf->plug); /* the unplug fn references 'conf'*/
Dan Williams95fc17a2009-07-31 12:39:15 +10005243 free_conf(conf);
NeilBrowna64c8762010-04-14 17:15:37 +10005244 mddev->private = NULL;
5245 mddev->to_remove = &raid5_attrs_group;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005246 return 0;
5247}
5248
Dan Williams45b42332007-07-09 11:56:43 -07005249#ifdef DEBUG
NeilBrownd710e132008-10-13 11:55:12 +11005250static void print_sh(struct seq_file *seq, struct stripe_head *sh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07005251{
5252 int i;
5253
NeilBrown16a53ec2006-06-26 00:27:38 -07005254 seq_printf(seq, "sh %llu, pd_idx %d, state %ld.\n",
5255 (unsigned long long)sh->sector, sh->pd_idx, sh->state);
5256 seq_printf(seq, "sh %llu, count %d.\n",
5257 (unsigned long long)sh->sector, atomic_read(&sh->count));
5258 seq_printf(seq, "sh %llu, ", (unsigned long long)sh->sector);
NeilBrown7ecaa1e2006-03-27 01:18:08 -08005259 for (i = 0; i < sh->disks; i++) {
NeilBrown16a53ec2006-06-26 00:27:38 -07005260 seq_printf(seq, "(cache%d: %p %ld) ",
5261 i, sh->dev[i].page, sh->dev[i].flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005262 }
NeilBrown16a53ec2006-06-26 00:27:38 -07005263 seq_printf(seq, "\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07005264}
5265
NeilBrownd710e132008-10-13 11:55:12 +11005266static void printall(struct seq_file *seq, raid5_conf_t *conf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07005267{
5268 struct stripe_head *sh;
NeilBrownfccddba2006-01-06 00:20:33 -08005269 struct hlist_node *hn;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005270 int i;
5271
5272 spin_lock_irq(&conf->device_lock);
5273 for (i = 0; i < NR_HASH; i++) {
NeilBrownfccddba2006-01-06 00:20:33 -08005274 hlist_for_each_entry(sh, hn, &conf->stripe_hashtbl[i], hash) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07005275 if (sh->raid_conf != conf)
5276 continue;
NeilBrown16a53ec2006-06-26 00:27:38 -07005277 print_sh(seq, sh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005278 }
5279 }
5280 spin_unlock_irq(&conf->device_lock);
5281}
5282#endif
5283
NeilBrownd710e132008-10-13 11:55:12 +11005284static void status(struct seq_file *seq, mddev_t *mddev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07005285{
H Hartley Sweeten7b928132010-03-08 16:02:40 +11005286 raid5_conf_t *conf = mddev->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005287 int i;
5288
Andre Noll9d8f0362009-06-18 08:45:01 +10005289 seq_printf(seq, " level %d, %dk chunk, algorithm %d", mddev->level,
5290 mddev->chunk_sectors / 2, mddev->layout);
NeilBrown02c2de82006-10-03 01:15:47 -07005291 seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005292 for (i = 0; i < conf->raid_disks; i++)
5293 seq_printf (seq, "%s",
5294 conf->disks[i].rdev &&
NeilBrownb2d444d2005-11-08 21:39:31 -08005295 test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_");
Linus Torvalds1da177e2005-04-16 15:20:36 -07005296 seq_printf (seq, "]");
Dan Williams45b42332007-07-09 11:56:43 -07005297#ifdef DEBUG
NeilBrown16a53ec2006-06-26 00:27:38 -07005298 seq_printf (seq, "\n");
5299 printall(seq, conf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005300#endif
5301}
5302
5303static void print_raid5_conf (raid5_conf_t *conf)
5304{
5305 int i;
5306 struct disk_info *tmp;
5307
NeilBrown0c55e022010-05-03 14:09:02 +10005308 printk(KERN_DEBUG "RAID conf printout:\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07005309 if (!conf) {
5310 printk("(conf==NULL)\n");
5311 return;
5312 }
NeilBrown0c55e022010-05-03 14:09:02 +10005313 printk(KERN_DEBUG " --- level:%d rd:%d wd:%d\n", conf->level,
5314 conf->raid_disks,
5315 conf->raid_disks - conf->mddev->degraded);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005316
5317 for (i = 0; i < conf->raid_disks; i++) {
5318 char b[BDEVNAME_SIZE];
5319 tmp = conf->disks + i;
5320 if (tmp->rdev)
NeilBrown0c55e022010-05-03 14:09:02 +10005321 printk(KERN_DEBUG " disk %d, o:%d, dev:%s\n",
5322 i, !test_bit(Faulty, &tmp->rdev->flags),
5323 bdevname(tmp->rdev->bdev, b));
Linus Torvalds1da177e2005-04-16 15:20:36 -07005324 }
5325}
5326
5327static int raid5_spare_active(mddev_t *mddev)
5328{
5329 int i;
5330 raid5_conf_t *conf = mddev->private;
5331 struct disk_info *tmp;
NeilBrown6b965622010-08-18 11:56:59 +10005332 int count = 0;
5333 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005334
5335 for (i = 0; i < conf->raid_disks; i++) {
5336 tmp = conf->disks + i;
5337 if (tmp->rdev
NeilBrown70fffd02010-06-16 17:01:25 +10005338 && tmp->rdev->recovery_offset == MaxSector
NeilBrownb2d444d2005-11-08 21:39:31 -08005339 && !test_bit(Faulty, &tmp->rdev->flags)
NeilBrownc04be0a2006-10-03 01:15:53 -07005340 && !test_and_set_bit(In_sync, &tmp->rdev->flags)) {
NeilBrown6b965622010-08-18 11:56:59 +10005341 count++;
Adrian Drzewieckie6ffbcb2010-08-18 11:49:02 +10005342 sysfs_notify_dirent(tmp->rdev->sysfs_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005343 }
5344 }
NeilBrown6b965622010-08-18 11:56:59 +10005345 spin_lock_irqsave(&conf->device_lock, flags);
5346 mddev->degraded -= count;
5347 spin_unlock_irqrestore(&conf->device_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005348 print_raid5_conf(conf);
NeilBrown6b965622010-08-18 11:56:59 +10005349 return count;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005350}
5351
5352static int raid5_remove_disk(mddev_t *mddev, int number)
5353{
5354 raid5_conf_t *conf = mddev->private;
5355 int err = 0;
5356 mdk_rdev_t *rdev;
5357 struct disk_info *p = conf->disks + number;
5358
5359 print_raid5_conf(conf);
5360 rdev = p->rdev;
5361 if (rdev) {
NeilBrownec32a2b2009-03-31 15:17:38 +11005362 if (number >= conf->raid_disks &&
5363 conf->reshape_progress == MaxSector)
5364 clear_bit(In_sync, &rdev->flags);
5365
NeilBrownb2d444d2005-11-08 21:39:31 -08005366 if (test_bit(In_sync, &rdev->flags) ||
Linus Torvalds1da177e2005-04-16 15:20:36 -07005367 atomic_read(&rdev->nr_pending)) {
5368 err = -EBUSY;
5369 goto abort;
5370 }
NeilBrowndfc70642008-05-23 13:04:39 -07005371 /* Only remove non-faulty devices if recovery
5372 * isn't possible.
5373 */
5374 if (!test_bit(Faulty, &rdev->flags) &&
NeilBrown674806d2010-06-16 17:17:53 +10005375 !has_failed(conf) &&
NeilBrownec32a2b2009-03-31 15:17:38 +11005376 number < conf->raid_disks) {
NeilBrowndfc70642008-05-23 13:04:39 -07005377 err = -EBUSY;
5378 goto abort;
5379 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07005380 p->rdev = NULL;
Paul E. McKenneyfbd568a3e2005-05-01 08:59:04 -07005381 synchronize_rcu();
Linus Torvalds1da177e2005-04-16 15:20:36 -07005382 if (atomic_read(&rdev->nr_pending)) {
5383 /* lost the race, try later */
5384 err = -EBUSY;
5385 p->rdev = rdev;
5386 }
5387 }
5388abort:
5389
5390 print_raid5_conf(conf);
5391 return err;
5392}
5393
5394static int raid5_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
5395{
5396 raid5_conf_t *conf = mddev->private;
Neil Brown199050e2008-06-28 08:31:33 +10005397 int err = -EEXIST;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005398 int disk;
5399 struct disk_info *p;
Neil Brown6c2fce22008-06-28 08:31:31 +10005400 int first = 0;
5401 int last = conf->raid_disks - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005402
NeilBrown674806d2010-06-16 17:17:53 +10005403 if (has_failed(conf))
Linus Torvalds1da177e2005-04-16 15:20:36 -07005404 /* no point adding a device */
Neil Brown199050e2008-06-28 08:31:33 +10005405 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005406
Neil Brown6c2fce22008-06-28 08:31:31 +10005407 if (rdev->raid_disk >= 0)
5408 first = last = rdev->raid_disk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005409
5410 /*
NeilBrown16a53ec2006-06-26 00:27:38 -07005411 * find the disk ... but prefer rdev->saved_raid_disk
5412 * if possible.
Linus Torvalds1da177e2005-04-16 15:20:36 -07005413 */
NeilBrown16a53ec2006-06-26 00:27:38 -07005414 if (rdev->saved_raid_disk >= 0 &&
Neil Brown6c2fce22008-06-28 08:31:31 +10005415 rdev->saved_raid_disk >= first &&
NeilBrown16a53ec2006-06-26 00:27:38 -07005416 conf->disks[rdev->saved_raid_disk].rdev == NULL)
5417 disk = rdev->saved_raid_disk;
5418 else
Neil Brown6c2fce22008-06-28 08:31:31 +10005419 disk = first;
5420 for ( ; disk <= last ; disk++)
Linus Torvalds1da177e2005-04-16 15:20:36 -07005421 if ((p=conf->disks + disk)->rdev == NULL) {
NeilBrownb2d444d2005-11-08 21:39:31 -08005422 clear_bit(In_sync, &rdev->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005423 rdev->raid_disk = disk;
Neil Brown199050e2008-06-28 08:31:33 +10005424 err = 0;
NeilBrown72626682005-09-09 16:23:54 -07005425 if (rdev->saved_raid_disk != disk)
5426 conf->fullsync = 1;
Suzanne Woodd6065f72005-11-08 21:39:27 -08005427 rcu_assign_pointer(p->rdev, rdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005428 break;
5429 }
5430 print_raid5_conf(conf);
Neil Brown199050e2008-06-28 08:31:33 +10005431 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005432}
5433
5434static int raid5_resize(mddev_t *mddev, sector_t sectors)
5435{
5436 /* no resync is happening, and there is enough space
5437 * on all devices, so we can resize.
5438 * We need to make sure resync covers any new space.
5439 * If the array is shrinking we should possibly wait until
5440 * any io in the removed space completes, but it hardly seems
5441 * worth it.
5442 */
Andre Noll9d8f0362009-06-18 08:45:01 +10005443 sectors &= ~((sector_t)mddev->chunk_sectors - 1);
Dan Williams1f403622009-03-31 14:59:03 +11005444 md_set_array_sectors(mddev, raid5_size(mddev, sectors,
5445 mddev->raid_disks));
Dan Williamsb522adc2009-03-31 15:00:31 +11005446 if (mddev->array_sectors >
5447 raid5_size(mddev, sectors, mddev->raid_disks))
5448 return -EINVAL;
Andre Nollf233ea52008-07-21 17:05:22 +10005449 set_capacity(mddev->gendisk, mddev->array_sectors);
NeilBrown449aad32009-08-03 10:59:58 +10005450 revalidate_disk(mddev->gendisk);
Andre Noll58c0fed2009-03-31 14:33:13 +11005451 if (sectors > mddev->dev_sectors && mddev->recovery_cp == MaxSector) {
5452 mddev->recovery_cp = mddev->dev_sectors;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005453 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5454 }
Andre Noll58c0fed2009-03-31 14:33:13 +11005455 mddev->dev_sectors = sectors;
NeilBrown4b5c7ae2005-07-27 11:43:28 -07005456 mddev->resync_max_sectors = sectors;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005457 return 0;
5458}
5459
NeilBrown01ee22b2009-06-18 08:47:20 +10005460static int check_stripe_cache(mddev_t *mddev)
5461{
5462 /* Can only proceed if there are plenty of stripe_heads.
5463 * We need a minimum of one full stripe,, and for sensible progress
5464 * it is best to have about 4 times that.
5465 * If we require 4 times, then the default 256 4K stripe_heads will
5466 * allow for chunk sizes up to 256K, which is probably OK.
5467 * If the chunk size is greater, user-space should request more
5468 * stripe_heads first.
5469 */
5470 raid5_conf_t *conf = mddev->private;
5471 if (((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4
5472 > conf->max_nr_stripes ||
5473 ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4
5474 > conf->max_nr_stripes) {
NeilBrown0c55e022010-05-03 14:09:02 +10005475 printk(KERN_WARNING "md/raid:%s: reshape: not enough stripes. Needed %lu\n",
5476 mdname(mddev),
NeilBrown01ee22b2009-06-18 08:47:20 +10005477 ((max(mddev->chunk_sectors, mddev->new_chunk_sectors) << 9)
5478 / STRIPE_SIZE)*4);
5479 return 0;
5480 }
5481 return 1;
5482}
5483
NeilBrown50ac1682009-06-18 08:47:55 +10005484static int check_reshape(mddev_t *mddev)
NeilBrown29269552006-03-27 01:18:10 -08005485{
NeilBrown070ec552009-06-16 16:54:21 +10005486 raid5_conf_t *conf = mddev->private;
NeilBrown29269552006-03-27 01:18:10 -08005487
NeilBrown88ce4932009-03-31 15:24:23 +11005488 if (mddev->delta_disks == 0 &&
5489 mddev->new_layout == mddev->layout &&
Andre Noll664e7c42009-06-18 08:45:27 +10005490 mddev->new_chunk_sectors == mddev->chunk_sectors)
NeilBrown50ac1682009-06-18 08:47:55 +10005491 return 0; /* nothing to do */
NeilBrowndba034e2008-08-05 15:54:13 +10005492 if (mddev->bitmap)
5493 /* Cannot grow a bitmap yet */
5494 return -EBUSY;
NeilBrown674806d2010-06-16 17:17:53 +10005495 if (has_failed(conf))
NeilBrownec32a2b2009-03-31 15:17:38 +11005496 return -EINVAL;
5497 if (mddev->delta_disks < 0) {
5498 /* We might be able to shrink, but the devices must
5499 * be made bigger first.
5500 * For raid6, 4 is the minimum size.
5501 * Otherwise 2 is the minimum
5502 */
5503 int min = 2;
5504 if (mddev->level == 6)
5505 min = 4;
5506 if (mddev->raid_disks + mddev->delta_disks < min)
5507 return -EINVAL;
5508 }
NeilBrown29269552006-03-27 01:18:10 -08005509
NeilBrown01ee22b2009-06-18 08:47:20 +10005510 if (!check_stripe_cache(mddev))
NeilBrown29269552006-03-27 01:18:10 -08005511 return -ENOSPC;
NeilBrown29269552006-03-27 01:18:10 -08005512
NeilBrownec32a2b2009-03-31 15:17:38 +11005513 return resize_stripes(conf, conf->raid_disks + mddev->delta_disks);
NeilBrown63c70c42006-03-27 01:18:13 -08005514}
5515
5516static int raid5_start_reshape(mddev_t *mddev)
5517{
NeilBrown070ec552009-06-16 16:54:21 +10005518 raid5_conf_t *conf = mddev->private;
NeilBrown63c70c42006-03-27 01:18:13 -08005519 mdk_rdev_t *rdev;
NeilBrown63c70c42006-03-27 01:18:13 -08005520 int spares = 0;
5521 int added_devices = 0;
NeilBrownc04be0a2006-10-03 01:15:53 -07005522 unsigned long flags;
NeilBrown63c70c42006-03-27 01:18:13 -08005523
NeilBrownf4168852007-02-28 20:11:53 -08005524 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
NeilBrown63c70c42006-03-27 01:18:13 -08005525 return -EBUSY;
5526
NeilBrown01ee22b2009-06-18 08:47:20 +10005527 if (!check_stripe_cache(mddev))
5528 return -ENOSPC;
5529
Cheng Renquan159ec1f2009-01-09 08:31:08 +11005530 list_for_each_entry(rdev, &mddev->disks, same_set)
NeilBrown29269552006-03-27 01:18:10 -08005531 if (rdev->raid_disk < 0 &&
5532 !test_bit(Faulty, &rdev->flags))
5533 spares++;
NeilBrown63c70c42006-03-27 01:18:13 -08005534
NeilBrownf4168852007-02-28 20:11:53 -08005535 if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded)
NeilBrown29269552006-03-27 01:18:10 -08005536 /* Not enough devices even to make a degraded array
5537 * of that size
5538 */
5539 return -EINVAL;
5540
NeilBrownec32a2b2009-03-31 15:17:38 +11005541 /* Refuse to reduce size of the array. Any reductions in
5542 * array size must be through explicit setting of array_size
5543 * attribute.
5544 */
5545 if (raid5_size(mddev, 0, conf->raid_disks + mddev->delta_disks)
5546 < mddev->array_sectors) {
NeilBrown0c55e022010-05-03 14:09:02 +10005547 printk(KERN_ERR "md/raid:%s: array size must be reduced "
NeilBrownec32a2b2009-03-31 15:17:38 +11005548 "before number of disks\n", mdname(mddev));
5549 return -EINVAL;
5550 }
5551
NeilBrownf6705572006-03-27 01:18:11 -08005552 atomic_set(&conf->reshape_stripes, 0);
NeilBrown29269552006-03-27 01:18:10 -08005553 spin_lock_irq(&conf->device_lock);
5554 conf->previous_raid_disks = conf->raid_disks;
NeilBrown63c70c42006-03-27 01:18:13 -08005555 conf->raid_disks += mddev->delta_disks;
Andre Noll09c9e5f2009-06-18 08:45:55 +10005556 conf->prev_chunk_sectors = conf->chunk_sectors;
5557 conf->chunk_sectors = mddev->new_chunk_sectors;
NeilBrown88ce4932009-03-31 15:24:23 +11005558 conf->prev_algo = conf->algorithm;
5559 conf->algorithm = mddev->new_layout;
NeilBrownfef9c612009-03-31 15:16:46 +11005560 if (mddev->delta_disks < 0)
5561 conf->reshape_progress = raid5_size(mddev, 0, 0);
5562 else
5563 conf->reshape_progress = 0;
5564 conf->reshape_safe = conf->reshape_progress;
NeilBrown86b42c72009-03-31 15:19:03 +11005565 conf->generation++;
NeilBrown29269552006-03-27 01:18:10 -08005566 spin_unlock_irq(&conf->device_lock);
5567
5568 /* Add some new drives, as many as will fit.
5569 * We know there are enough to make the newly sized array work.
NeilBrown3424bf62010-06-17 17:48:26 +10005570 * Don't add devices if we are reducing the number of
5571 * devices in the array. This is because it is not possible
5572 * to correctly record the "partially reconstructed" state of
5573 * such devices during the reshape and confusion could result.
NeilBrown29269552006-03-27 01:18:10 -08005574 */
NeilBrown3424bf62010-06-17 17:48:26 +10005575 if (mddev->delta_disks >= 0)
5576 list_for_each_entry(rdev, &mddev->disks, same_set)
NeilBrown29269552006-03-27 01:18:10 -08005577 if (rdev->raid_disk < 0 &&
5578 !test_bit(Faulty, &rdev->flags)) {
Neil Brown199050e2008-06-28 08:31:33 +10005579 if (raid5_add_disk(mddev, rdev) == 0) {
NeilBrown29269552006-03-27 01:18:10 -08005580 char nm[20];
NeilBrown9eb07c22010-02-09 12:31:47 +11005581 if (rdev->raid_disk >= conf->previous_raid_disks) {
NeilBrown7ef90142009-11-13 17:40:51 +11005582 set_bit(In_sync, &rdev->flags);
NeilBrown9eb07c22010-02-09 12:31:47 +11005583 added_devices++;
5584 } else
NeilBrown7ef90142009-11-13 17:40:51 +11005585 rdev->recovery_offset = 0;
NeilBrown29269552006-03-27 01:18:10 -08005586 sprintf(nm, "rd%d", rdev->raid_disk);
NeilBrown5e55e2f2007-03-26 21:32:14 -08005587 if (sysfs_create_link(&mddev->kobj,
5588 &rdev->kobj, nm))
NeilBrown00bcb4a2010-06-01 19:37:23 +10005589 /* Failure here is OK */;
NeilBrown29269552006-03-27 01:18:10 -08005590 } else
5591 break;
5592 }
5593
NeilBrown9eb07c22010-02-09 12:31:47 +11005594 /* When a reshape changes the number of devices, ->degraded
NeilBrown3424bf62010-06-17 17:48:26 +10005595 * is measured against the larger of the pre and post number of
NeilBrown9eb07c22010-02-09 12:31:47 +11005596 * devices.*/
NeilBrownec32a2b2009-03-31 15:17:38 +11005597 if (mddev->delta_disks > 0) {
5598 spin_lock_irqsave(&conf->device_lock, flags);
NeilBrown9eb07c22010-02-09 12:31:47 +11005599 mddev->degraded += (conf->raid_disks - conf->previous_raid_disks)
NeilBrownec32a2b2009-03-31 15:17:38 +11005600 - added_devices;
5601 spin_unlock_irqrestore(&conf->device_lock, flags);
5602 }
NeilBrown63c70c42006-03-27 01:18:13 -08005603 mddev->raid_disks = conf->raid_disks;
NeilBrowne5164022009-08-03 10:59:57 +10005604 mddev->reshape_position = conf->reshape_progress;
NeilBrown850b2b42006-10-03 01:15:46 -07005605 set_bit(MD_CHANGE_DEVS, &mddev->flags);
NeilBrownf6705572006-03-27 01:18:11 -08005606
NeilBrown29269552006-03-27 01:18:10 -08005607 clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
5608 clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
5609 set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
5610 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
5611 mddev->sync_thread = md_register_thread(md_do_sync, mddev,
NeilBrown0da3c612009-09-23 18:09:45 +10005612 "reshape");
NeilBrown29269552006-03-27 01:18:10 -08005613 if (!mddev->sync_thread) {
5614 mddev->recovery = 0;
5615 spin_lock_irq(&conf->device_lock);
5616 mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks;
NeilBrownfef9c612009-03-31 15:16:46 +11005617 conf->reshape_progress = MaxSector;
NeilBrown29269552006-03-27 01:18:10 -08005618 spin_unlock_irq(&conf->device_lock);
5619 return -EAGAIN;
5620 }
NeilBrownc8f517c2009-03-31 15:28:40 +11005621 conf->reshape_checkpoint = jiffies;
NeilBrown29269552006-03-27 01:18:10 -08005622 md_wakeup_thread(mddev->sync_thread);
5623 md_new_event(mddev);
5624 return 0;
5625}
NeilBrown29269552006-03-27 01:18:10 -08005626
NeilBrownec32a2b2009-03-31 15:17:38 +11005627/* This is called from the reshape thread and should make any
5628 * changes needed in 'conf'
5629 */
NeilBrown29269552006-03-27 01:18:10 -08005630static void end_reshape(raid5_conf_t *conf)
5631{
NeilBrown29269552006-03-27 01:18:10 -08005632
NeilBrownf6705572006-03-27 01:18:11 -08005633 if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) {
Dan Williams80c3a6c2009-03-17 18:10:40 -07005634
NeilBrownf6705572006-03-27 01:18:11 -08005635 spin_lock_irq(&conf->device_lock);
NeilBrowncea9c222009-03-31 15:15:05 +11005636 conf->previous_raid_disks = conf->raid_disks;
NeilBrownfef9c612009-03-31 15:16:46 +11005637 conf->reshape_progress = MaxSector;
NeilBrownf6705572006-03-27 01:18:11 -08005638 spin_unlock_irq(&conf->device_lock);
NeilBrownb0f9ec02009-03-31 15:27:18 +11005639 wake_up(&conf->wait_for_overlap);
NeilBrown16a53ec2006-06-26 00:27:38 -07005640
5641 /* read-ahead size must cover two whole stripes, which is
5642 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
5643 */
NeilBrown4a5add42010-06-01 19:37:28 +10005644 if (conf->mddev->queue) {
NeilBrowncea9c222009-03-31 15:15:05 +11005645 int data_disks = conf->raid_disks - conf->max_degraded;
Andre Noll09c9e5f2009-06-18 08:45:55 +10005646 int stripe = data_disks * ((conf->chunk_sectors << 9)
NeilBrowncea9c222009-03-31 15:15:05 +11005647 / PAGE_SIZE);
NeilBrown16a53ec2006-06-26 00:27:38 -07005648 if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe)
5649 conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe;
5650 }
NeilBrown29269552006-03-27 01:18:10 -08005651 }
NeilBrown29269552006-03-27 01:18:10 -08005652}
5653
NeilBrownec32a2b2009-03-31 15:17:38 +11005654/* This is called from the raid5d thread with mddev_lock held.
5655 * It makes config changes to the device.
5656 */
NeilBrowncea9c222009-03-31 15:15:05 +11005657static void raid5_finish_reshape(mddev_t *mddev)
5658{
NeilBrown070ec552009-06-16 16:54:21 +10005659 raid5_conf_t *conf = mddev->private;
NeilBrowncea9c222009-03-31 15:15:05 +11005660
5661 if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
5662
NeilBrownec32a2b2009-03-31 15:17:38 +11005663 if (mddev->delta_disks > 0) {
5664 md_set_array_sectors(mddev, raid5_size(mddev, 0, 0));
5665 set_capacity(mddev->gendisk, mddev->array_sectors);
NeilBrown449aad32009-08-03 10:59:58 +10005666 revalidate_disk(mddev->gendisk);
NeilBrownec32a2b2009-03-31 15:17:38 +11005667 } else {
5668 int d;
NeilBrownec32a2b2009-03-31 15:17:38 +11005669 mddev->degraded = conf->raid_disks;
5670 for (d = 0; d < conf->raid_disks ; d++)
5671 if (conf->disks[d].rdev &&
5672 test_bit(In_sync,
5673 &conf->disks[d].rdev->flags))
5674 mddev->degraded--;
5675 for (d = conf->raid_disks ;
5676 d < conf->raid_disks - mddev->delta_disks;
NeilBrown1a67dde2009-08-13 10:41:49 +10005677 d++) {
5678 mdk_rdev_t *rdev = conf->disks[d].rdev;
5679 if (rdev && raid5_remove_disk(mddev, d) == 0) {
5680 char nm[20];
5681 sprintf(nm, "rd%d", rdev->raid_disk);
5682 sysfs_remove_link(&mddev->kobj, nm);
5683 rdev->raid_disk = -1;
5684 }
5685 }
NeilBrowncea9c222009-03-31 15:15:05 +11005686 }
NeilBrown88ce4932009-03-31 15:24:23 +11005687 mddev->layout = conf->algorithm;
Andre Noll09c9e5f2009-06-18 08:45:55 +10005688 mddev->chunk_sectors = conf->chunk_sectors;
NeilBrownec32a2b2009-03-31 15:17:38 +11005689 mddev->reshape_position = MaxSector;
5690 mddev->delta_disks = 0;
NeilBrowncea9c222009-03-31 15:15:05 +11005691 }
5692}
5693
NeilBrown72626682005-09-09 16:23:54 -07005694static void raid5_quiesce(mddev_t *mddev, int state)
5695{
NeilBrown070ec552009-06-16 16:54:21 +10005696 raid5_conf_t *conf = mddev->private;
NeilBrown72626682005-09-09 16:23:54 -07005697
5698 switch(state) {
NeilBrowne464eaf2006-03-27 01:18:14 -08005699 case 2: /* resume for a suspend */
5700 wake_up(&conf->wait_for_overlap);
5701 break;
5702
NeilBrown72626682005-09-09 16:23:54 -07005703 case 1: /* stop all writes */
5704 spin_lock_irq(&conf->device_lock);
NeilBrown64bd6602009-08-03 10:59:58 +10005705 /* '2' tells resync/reshape to pause so that all
5706 * active stripes can drain
5707 */
5708 conf->quiesce = 2;
NeilBrown72626682005-09-09 16:23:54 -07005709 wait_event_lock_irq(conf->wait_for_stripe,
Raz Ben-Jehuda(caro)46031f92006-12-10 02:20:47 -08005710 atomic_read(&conf->active_stripes) == 0 &&
5711 atomic_read(&conf->active_aligned_reads) == 0,
NeilBrown72626682005-09-09 16:23:54 -07005712 conf->device_lock, /* nothing */);
NeilBrown64bd6602009-08-03 10:59:58 +10005713 conf->quiesce = 1;
NeilBrown72626682005-09-09 16:23:54 -07005714 spin_unlock_irq(&conf->device_lock);
NeilBrown64bd6602009-08-03 10:59:58 +10005715 /* allow reshape to continue */
5716 wake_up(&conf->wait_for_overlap);
NeilBrown72626682005-09-09 16:23:54 -07005717 break;
5718
5719 case 0: /* re-enable writes */
5720 spin_lock_irq(&conf->device_lock);
5721 conf->quiesce = 0;
5722 wake_up(&conf->wait_for_stripe);
NeilBrowne464eaf2006-03-27 01:18:14 -08005723 wake_up(&conf->wait_for_overlap);
NeilBrown72626682005-09-09 16:23:54 -07005724 spin_unlock_irq(&conf->device_lock);
5725 break;
5726 }
NeilBrown72626682005-09-09 16:23:54 -07005727}
NeilBrownb15c2e52006-01-06 00:20:16 -08005728
NeilBrownd562b0c2009-03-31 14:39:39 +11005729
Dan Williamsf1b29bc2010-05-01 18:09:05 -07005730static void *raid45_takeover_raid0(mddev_t *mddev, int level)
Trela Maciej54071b32010-03-08 16:02:42 +11005731{
Dan Williamsf1b29bc2010-05-01 18:09:05 -07005732 struct raid0_private_data *raid0_priv = mddev->private;
Trela Maciej54071b32010-03-08 16:02:42 +11005733
Dan Williamsf1b29bc2010-05-01 18:09:05 -07005734 /* for raid0 takeover only one zone is supported */
5735 if (raid0_priv->nr_strip_zones > 1) {
NeilBrown0c55e022010-05-03 14:09:02 +10005736 printk(KERN_ERR "md/raid:%s: cannot takeover raid0 with more than one zone.\n",
5737 mdname(mddev));
Dan Williamsf1b29bc2010-05-01 18:09:05 -07005738 return ERR_PTR(-EINVAL);
5739 }
5740
5741 mddev->new_level = level;
Trela Maciej54071b32010-03-08 16:02:42 +11005742 mddev->new_layout = ALGORITHM_PARITY_N;
5743 mddev->new_chunk_sectors = mddev->chunk_sectors;
5744 mddev->raid_disks += 1;
5745 mddev->delta_disks = 1;
5746 /* make sure it will be not marked as dirty */
5747 mddev->recovery_cp = MaxSector;
5748
5749 return setup_conf(mddev);
5750}
5751
5752
NeilBrownd562b0c2009-03-31 14:39:39 +11005753static void *raid5_takeover_raid1(mddev_t *mddev)
5754{
5755 int chunksect;
5756
5757 if (mddev->raid_disks != 2 ||
5758 mddev->degraded > 1)
5759 return ERR_PTR(-EINVAL);
5760
5761 /* Should check if there are write-behind devices? */
5762
5763 chunksect = 64*2; /* 64K by default */
5764
5765 /* The array must be an exact multiple of chunksize */
5766 while (chunksect && (mddev->array_sectors & (chunksect-1)))
5767 chunksect >>= 1;
5768
5769 if ((chunksect<<9) < STRIPE_SIZE)
5770 /* array size does not allow a suitable chunk size */
5771 return ERR_PTR(-EINVAL);
5772
5773 mddev->new_level = 5;
5774 mddev->new_layout = ALGORITHM_LEFT_SYMMETRIC;
Andre Noll664e7c42009-06-18 08:45:27 +10005775 mddev->new_chunk_sectors = chunksect;
NeilBrownd562b0c2009-03-31 14:39:39 +11005776
5777 return setup_conf(mddev);
5778}
5779
NeilBrownfc9739c2009-03-31 14:57:20 +11005780static void *raid5_takeover_raid6(mddev_t *mddev)
5781{
5782 int new_layout;
5783
5784 switch (mddev->layout) {
5785 case ALGORITHM_LEFT_ASYMMETRIC_6:
5786 new_layout = ALGORITHM_LEFT_ASYMMETRIC;
5787 break;
5788 case ALGORITHM_RIGHT_ASYMMETRIC_6:
5789 new_layout = ALGORITHM_RIGHT_ASYMMETRIC;
5790 break;
5791 case ALGORITHM_LEFT_SYMMETRIC_6:
5792 new_layout = ALGORITHM_LEFT_SYMMETRIC;
5793 break;
5794 case ALGORITHM_RIGHT_SYMMETRIC_6:
5795 new_layout = ALGORITHM_RIGHT_SYMMETRIC;
5796 break;
5797 case ALGORITHM_PARITY_0_6:
5798 new_layout = ALGORITHM_PARITY_0;
5799 break;
5800 case ALGORITHM_PARITY_N:
5801 new_layout = ALGORITHM_PARITY_N;
5802 break;
5803 default:
5804 return ERR_PTR(-EINVAL);
5805 }
5806 mddev->new_level = 5;
5807 mddev->new_layout = new_layout;
5808 mddev->delta_disks = -1;
5809 mddev->raid_disks -= 1;
5810 return setup_conf(mddev);
5811}
5812
NeilBrownd562b0c2009-03-31 14:39:39 +11005813
NeilBrown50ac1682009-06-18 08:47:55 +10005814static int raid5_check_reshape(mddev_t *mddev)
NeilBrownb3546032009-03-31 14:56:41 +11005815{
NeilBrown88ce4932009-03-31 15:24:23 +11005816 /* For a 2-drive array, the layout and chunk size can be changed
5817 * immediately as not restriping is needed.
5818 * For larger arrays we record the new value - after validation
5819 * to be used by a reshape pass.
NeilBrownb3546032009-03-31 14:56:41 +11005820 */
NeilBrown070ec552009-06-16 16:54:21 +10005821 raid5_conf_t *conf = mddev->private;
NeilBrown597a7112009-06-18 08:47:42 +10005822 int new_chunk = mddev->new_chunk_sectors;
NeilBrownb3546032009-03-31 14:56:41 +11005823
NeilBrown597a7112009-06-18 08:47:42 +10005824 if (mddev->new_layout >= 0 && !algorithm_valid_raid5(mddev->new_layout))
NeilBrownb3546032009-03-31 14:56:41 +11005825 return -EINVAL;
5826 if (new_chunk > 0) {
Andre Noll0ba459d2009-06-18 08:46:10 +10005827 if (!is_power_of_2(new_chunk))
NeilBrownb3546032009-03-31 14:56:41 +11005828 return -EINVAL;
NeilBrown597a7112009-06-18 08:47:42 +10005829 if (new_chunk < (PAGE_SIZE>>9))
NeilBrownb3546032009-03-31 14:56:41 +11005830 return -EINVAL;
NeilBrown597a7112009-06-18 08:47:42 +10005831 if (mddev->array_sectors & (new_chunk-1))
NeilBrownb3546032009-03-31 14:56:41 +11005832 /* not factor of array size */
5833 return -EINVAL;
5834 }
5835
5836 /* They look valid */
5837
NeilBrown88ce4932009-03-31 15:24:23 +11005838 if (mddev->raid_disks == 2) {
NeilBrown597a7112009-06-18 08:47:42 +10005839 /* can make the change immediately */
5840 if (mddev->new_layout >= 0) {
5841 conf->algorithm = mddev->new_layout;
5842 mddev->layout = mddev->new_layout;
NeilBrown88ce4932009-03-31 15:24:23 +11005843 }
5844 if (new_chunk > 0) {
NeilBrown597a7112009-06-18 08:47:42 +10005845 conf->chunk_sectors = new_chunk ;
5846 mddev->chunk_sectors = new_chunk;
NeilBrown88ce4932009-03-31 15:24:23 +11005847 }
5848 set_bit(MD_CHANGE_DEVS, &mddev->flags);
5849 md_wakeup_thread(mddev->thread);
NeilBrownb3546032009-03-31 14:56:41 +11005850 }
NeilBrown50ac1682009-06-18 08:47:55 +10005851 return check_reshape(mddev);
NeilBrown88ce4932009-03-31 15:24:23 +11005852}
5853
NeilBrown50ac1682009-06-18 08:47:55 +10005854static int raid6_check_reshape(mddev_t *mddev)
NeilBrown88ce4932009-03-31 15:24:23 +11005855{
NeilBrown597a7112009-06-18 08:47:42 +10005856 int new_chunk = mddev->new_chunk_sectors;
NeilBrown50ac1682009-06-18 08:47:55 +10005857
NeilBrown597a7112009-06-18 08:47:42 +10005858 if (mddev->new_layout >= 0 && !algorithm_valid_raid6(mddev->new_layout))
NeilBrown88ce4932009-03-31 15:24:23 +11005859 return -EINVAL;
NeilBrownb3546032009-03-31 14:56:41 +11005860 if (new_chunk > 0) {
Andre Noll0ba459d2009-06-18 08:46:10 +10005861 if (!is_power_of_2(new_chunk))
NeilBrown88ce4932009-03-31 15:24:23 +11005862 return -EINVAL;
NeilBrown597a7112009-06-18 08:47:42 +10005863 if (new_chunk < (PAGE_SIZE >> 9))
NeilBrown88ce4932009-03-31 15:24:23 +11005864 return -EINVAL;
NeilBrown597a7112009-06-18 08:47:42 +10005865 if (mddev->array_sectors & (new_chunk-1))
NeilBrown88ce4932009-03-31 15:24:23 +11005866 /* not factor of array size */
5867 return -EINVAL;
NeilBrownb3546032009-03-31 14:56:41 +11005868 }
NeilBrown88ce4932009-03-31 15:24:23 +11005869
5870 /* They look valid */
NeilBrown50ac1682009-06-18 08:47:55 +10005871 return check_reshape(mddev);
NeilBrownb3546032009-03-31 14:56:41 +11005872}
5873
NeilBrownd562b0c2009-03-31 14:39:39 +11005874static void *raid5_takeover(mddev_t *mddev)
5875{
5876 /* raid5 can take over:
Dan Williamsf1b29bc2010-05-01 18:09:05 -07005877 * raid0 - if there is only one strip zone - make it a raid4 layout
NeilBrownd562b0c2009-03-31 14:39:39 +11005878 * raid1 - if there are two drives. We need to know the chunk size
5879 * raid4 - trivial - just use a raid4 layout.
5880 * raid6 - Providing it is a *_6 layout
NeilBrownd562b0c2009-03-31 14:39:39 +11005881 */
Dan Williamsf1b29bc2010-05-01 18:09:05 -07005882 if (mddev->level == 0)
5883 return raid45_takeover_raid0(mddev, 5);
NeilBrownd562b0c2009-03-31 14:39:39 +11005884 if (mddev->level == 1)
5885 return raid5_takeover_raid1(mddev);
NeilBrowne9d47582009-03-31 14:57:09 +11005886 if (mddev->level == 4) {
5887 mddev->new_layout = ALGORITHM_PARITY_N;
5888 mddev->new_level = 5;
5889 return setup_conf(mddev);
5890 }
NeilBrownfc9739c2009-03-31 14:57:20 +11005891 if (mddev->level == 6)
5892 return raid5_takeover_raid6(mddev);
NeilBrownd562b0c2009-03-31 14:39:39 +11005893
5894 return ERR_PTR(-EINVAL);
5895}
5896
NeilBrowna78d38a2010-03-22 16:53:49 +11005897static void *raid4_takeover(mddev_t *mddev)
5898{
Dan Williamsf1b29bc2010-05-01 18:09:05 -07005899 /* raid4 can take over:
5900 * raid0 - if there is only one strip zone
5901 * raid5 - if layout is right
NeilBrowna78d38a2010-03-22 16:53:49 +11005902 */
Dan Williamsf1b29bc2010-05-01 18:09:05 -07005903 if (mddev->level == 0)
5904 return raid45_takeover_raid0(mddev, 4);
NeilBrowna78d38a2010-03-22 16:53:49 +11005905 if (mddev->level == 5 &&
5906 mddev->layout == ALGORITHM_PARITY_N) {
5907 mddev->new_layout = 0;
5908 mddev->new_level = 4;
5909 return setup_conf(mddev);
5910 }
5911 return ERR_PTR(-EINVAL);
5912}
NeilBrownd562b0c2009-03-31 14:39:39 +11005913
NeilBrown245f46c2009-03-31 14:39:39 +11005914static struct mdk_personality raid5_personality;
5915
5916static void *raid6_takeover(mddev_t *mddev)
5917{
5918 /* Currently can only take over a raid5. We map the
5919 * personality to an equivalent raid6 personality
5920 * with the Q block at the end.
5921 */
5922 int new_layout;
5923
5924 if (mddev->pers != &raid5_personality)
5925 return ERR_PTR(-EINVAL);
5926 if (mddev->degraded > 1)
5927 return ERR_PTR(-EINVAL);
5928 if (mddev->raid_disks > 253)
5929 return ERR_PTR(-EINVAL);
5930 if (mddev->raid_disks < 3)
5931 return ERR_PTR(-EINVAL);
5932
5933 switch (mddev->layout) {
5934 case ALGORITHM_LEFT_ASYMMETRIC:
5935 new_layout = ALGORITHM_LEFT_ASYMMETRIC_6;
5936 break;
5937 case ALGORITHM_RIGHT_ASYMMETRIC:
5938 new_layout = ALGORITHM_RIGHT_ASYMMETRIC_6;
5939 break;
5940 case ALGORITHM_LEFT_SYMMETRIC:
5941 new_layout = ALGORITHM_LEFT_SYMMETRIC_6;
5942 break;
5943 case ALGORITHM_RIGHT_SYMMETRIC:
5944 new_layout = ALGORITHM_RIGHT_SYMMETRIC_6;
5945 break;
5946 case ALGORITHM_PARITY_0:
5947 new_layout = ALGORITHM_PARITY_0_6;
5948 break;
5949 case ALGORITHM_PARITY_N:
5950 new_layout = ALGORITHM_PARITY_N;
5951 break;
5952 default:
5953 return ERR_PTR(-EINVAL);
5954 }
5955 mddev->new_level = 6;
5956 mddev->new_layout = new_layout;
5957 mddev->delta_disks = 1;
5958 mddev->raid_disks += 1;
5959 return setup_conf(mddev);
5960}
5961
5962
NeilBrown16a53ec2006-06-26 00:27:38 -07005963static struct mdk_personality raid6_personality =
5964{
5965 .name = "raid6",
5966 .level = 6,
5967 .owner = THIS_MODULE,
5968 .make_request = make_request,
5969 .run = run,
5970 .stop = stop,
5971 .status = status,
5972 .error_handler = error,
5973 .hot_add_disk = raid5_add_disk,
5974 .hot_remove_disk= raid5_remove_disk,
5975 .spare_active = raid5_spare_active,
5976 .sync_request = sync_request,
5977 .resize = raid5_resize,
Dan Williams80c3a6c2009-03-17 18:10:40 -07005978 .size = raid5_size,
NeilBrown50ac1682009-06-18 08:47:55 +10005979 .check_reshape = raid6_check_reshape,
NeilBrownf4168852007-02-28 20:11:53 -08005980 .start_reshape = raid5_start_reshape,
NeilBrowncea9c222009-03-31 15:15:05 +11005981 .finish_reshape = raid5_finish_reshape,
NeilBrown16a53ec2006-06-26 00:27:38 -07005982 .quiesce = raid5_quiesce,
NeilBrown245f46c2009-03-31 14:39:39 +11005983 .takeover = raid6_takeover,
NeilBrown16a53ec2006-06-26 00:27:38 -07005984};
NeilBrown2604b702006-01-06 00:20:36 -08005985static struct mdk_personality raid5_personality =
Linus Torvalds1da177e2005-04-16 15:20:36 -07005986{
5987 .name = "raid5",
NeilBrown2604b702006-01-06 00:20:36 -08005988 .level = 5,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005989 .owner = THIS_MODULE,
5990 .make_request = make_request,
5991 .run = run,
5992 .stop = stop,
5993 .status = status,
5994 .error_handler = error,
5995 .hot_add_disk = raid5_add_disk,
5996 .hot_remove_disk= raid5_remove_disk,
5997 .spare_active = raid5_spare_active,
5998 .sync_request = sync_request,
5999 .resize = raid5_resize,
Dan Williams80c3a6c2009-03-17 18:10:40 -07006000 .size = raid5_size,
NeilBrown63c70c42006-03-27 01:18:13 -08006001 .check_reshape = raid5_check_reshape,
6002 .start_reshape = raid5_start_reshape,
NeilBrowncea9c222009-03-31 15:15:05 +11006003 .finish_reshape = raid5_finish_reshape,
NeilBrown72626682005-09-09 16:23:54 -07006004 .quiesce = raid5_quiesce,
NeilBrownd562b0c2009-03-31 14:39:39 +11006005 .takeover = raid5_takeover,
Linus Torvalds1da177e2005-04-16 15:20:36 -07006006};
6007
NeilBrown2604b702006-01-06 00:20:36 -08006008static struct mdk_personality raid4_personality =
Linus Torvalds1da177e2005-04-16 15:20:36 -07006009{
NeilBrown2604b702006-01-06 00:20:36 -08006010 .name = "raid4",
6011 .level = 4,
6012 .owner = THIS_MODULE,
6013 .make_request = make_request,
6014 .run = run,
6015 .stop = stop,
6016 .status = status,
6017 .error_handler = error,
6018 .hot_add_disk = raid5_add_disk,
6019 .hot_remove_disk= raid5_remove_disk,
6020 .spare_active = raid5_spare_active,
6021 .sync_request = sync_request,
6022 .resize = raid5_resize,
Dan Williams80c3a6c2009-03-17 18:10:40 -07006023 .size = raid5_size,
NeilBrown3d378902007-03-26 21:32:13 -08006024 .check_reshape = raid5_check_reshape,
6025 .start_reshape = raid5_start_reshape,
NeilBrowncea9c222009-03-31 15:15:05 +11006026 .finish_reshape = raid5_finish_reshape,
NeilBrown2604b702006-01-06 00:20:36 -08006027 .quiesce = raid5_quiesce,
NeilBrowna78d38a2010-03-22 16:53:49 +11006028 .takeover = raid4_takeover,
NeilBrown2604b702006-01-06 00:20:36 -08006029};
6030
6031static int __init raid5_init(void)
6032{
NeilBrown16a53ec2006-06-26 00:27:38 -07006033 register_md_personality(&raid6_personality);
NeilBrown2604b702006-01-06 00:20:36 -08006034 register_md_personality(&raid5_personality);
6035 register_md_personality(&raid4_personality);
6036 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07006037}
6038
NeilBrown2604b702006-01-06 00:20:36 -08006039static void raid5_exit(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07006040{
NeilBrown16a53ec2006-06-26 00:27:38 -07006041 unregister_md_personality(&raid6_personality);
NeilBrown2604b702006-01-06 00:20:36 -08006042 unregister_md_personality(&raid5_personality);
6043 unregister_md_personality(&raid4_personality);
Linus Torvalds1da177e2005-04-16 15:20:36 -07006044}
6045
6046module_init(raid5_init);
6047module_exit(raid5_exit);
6048MODULE_LICENSE("GPL");
NeilBrown0efb9e62009-12-14 12:49:58 +11006049MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
Linus Torvalds1da177e2005-04-16 15:20:36 -07006050MODULE_ALIAS("md-personality-4"); /* RAID5 */
NeilBrownd9d166c2006-01-06 00:20:51 -08006051MODULE_ALIAS("md-raid5");
6052MODULE_ALIAS("md-raid4");
NeilBrown2604b702006-01-06 00:20:36 -08006053MODULE_ALIAS("md-level-5");
6054MODULE_ALIAS("md-level-4");
NeilBrown16a53ec2006-06-26 00:27:38 -07006055MODULE_ALIAS("md-personality-8"); /* RAID6 */
6056MODULE_ALIAS("md-raid6");
6057MODULE_ALIAS("md-level-6");
6058
6059/* This used to be two separate modules, they were: */
6060MODULE_ALIAS("raid5");
6061MODULE_ALIAS("raid6");