blob: 16ba55ad708992f7e942b2f6ce2048d12be5c1b6 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright (C) 2001 Sistina Software (UK) Limited.
Mikulas Patockad5816872009-01-06 03:05:10 +00003 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
5 * This file is released under the GPL.
6 */
7
8#include "dm.h"
9
10#include <linux/module.h>
11#include <linux/vmalloc.h>
12#include <linux/blkdev.h>
13#include <linux/namei.h>
14#include <linux/ctype.h>
André Goddard Rosae7d28602009-12-14 18:01:06 -080015#include <linux/string.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <linux/slab.h>
17#include <linux/interrupt.h>
Arjan van de Ven48c9c272006-03-27 01:18:20 -080018#include <linux/mutex.h>
Mikulas Patockad5816872009-01-06 03:05:10 +000019#include <linux/delay.h>
Arun Sharma600634972011-07-26 16:09:06 -070020#include <linux/atomic.h>
Mike Snitzerbfebd1c2015-03-08 00:51:47 -050021#include <linux/blk-mq.h>
Dan Ehrenberg644bda62015-02-10 15:20:51 -080022#include <linux/mount.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
Alasdair G Kergon72d94862006-06-26 00:27:35 -070024#define DM_MSG_PREFIX "table"
25
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#define MAX_DEPTH 16
27#define NODE_SIZE L1_CACHE_BYTES
28#define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
29#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
30
31struct dm_table {
Mike Anderson1134e5a2006-03-27 01:17:54 -080032 struct mapped_device *md;
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +010033 unsigned type;
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
35 /* btree table */
36 unsigned int depth;
37 unsigned int counts[MAX_DEPTH]; /* in nodes */
38 sector_t *index[MAX_DEPTH];
39
40 unsigned int num_targets;
41 unsigned int num_allocated;
42 sector_t *highs;
43 struct dm_target *targets;
44
Alasdair G Kergon36a04562011-10-31 20:19:04 +000045 struct target_type *immutable_target_type;
Martin K. Petersena91a2782011-03-17 11:11:05 +010046 unsigned integrity_supported:1;
Alasdair G Kergon3791e2f2011-10-31 20:19:00 +000047 unsigned singleton:1;
Mike Snitzer5ae89a82010-08-12 04:14:08 +010048
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 /*
50 * Indicates the rw permissions for the new logical
51 * device. This should be a combination of FMODE_READ
52 * and FMODE_WRITE.
53 */
Al Viroaeb5d722008-09-02 15:28:45 -040054 fmode_t mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -070055
56 /* a list of devices used by this table */
57 struct list_head devices;
58
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 /* events get handed up using this callback */
60 void (*event_fn)(void *);
61 void *event_context;
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +010062
63 struct dm_md_mempools *mempools;
NeilBrown9d357b02011-01-13 20:00:01 +000064
65 struct list_head target_callbacks;
Linus Torvalds1da177e2005-04-16 15:20:36 -070066};
67
68/*
69 * Similar to ceiling(log_size(n))
70 */
71static unsigned int int_log(unsigned int n, unsigned int base)
72{
73 int result = 0;
74
75 while (n > 1) {
76 n = dm_div_up(n, base);
77 result++;
78 }
79
80 return result;
81}
82
83/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 * Calculate the index of the child node of the n'th node k'th key.
85 */
86static inline unsigned int get_child(unsigned int n, unsigned int k)
87{
88 return (n * CHILDREN_PER_NODE) + k;
89}
90
91/*
92 * Return the n'th node of level l from table t.
93 */
94static inline sector_t *get_node(struct dm_table *t,
95 unsigned int l, unsigned int n)
96{
97 return t->index[l] + (n * KEYS_PER_NODE);
98}
99
100/*
101 * Return the highest key that you could lookup from the n'th
102 * node on level l of the btree.
103 */
104static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
105{
106 for (; l < t->depth - 1; l++)
107 n = get_child(n, CHILDREN_PER_NODE - 1);
108
109 if (n >= t->counts[l])
110 return (sector_t) - 1;
111
112 return get_node(t, l, n)[KEYS_PER_NODE - 1];
113}
114
115/*
116 * Fills in a level of the btree based on the highs of the level
117 * below it.
118 */
119static int setup_btree_index(unsigned int l, struct dm_table *t)
120{
121 unsigned int n, k;
122 sector_t *node;
123
124 for (n = 0U; n < t->counts[l]; n++) {
125 node = get_node(t, l, n);
126
127 for (k = 0U; k < KEYS_PER_NODE; k++)
128 node[k] = high(t, l + 1, get_child(n, k));
129 }
130
131 return 0;
132}
133
134void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size)
135{
136 unsigned long size;
137 void *addr;
138
139 /*
140 * Check that we're not going to overflow.
141 */
142 if (nmemb > (ULONG_MAX / elem_size))
143 return NULL;
144
145 size = nmemb * elem_size;
Joe Perchese29e65a2011-08-02 12:32:02 +0100146 addr = vzalloc(size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147
148 return addr;
149}
Mike Snitzer08649012011-08-02 12:32:04 +0100150EXPORT_SYMBOL(dm_vcalloc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151
152/*
153 * highs, and targets are managed as dynamic arrays during a
154 * table load.
155 */
156static int alloc_targets(struct dm_table *t, unsigned int num)
157{
158 sector_t *n_highs;
159 struct dm_target *n_targets;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160
161 /*
162 * Allocate both the target array and offset array at once.
Jun'ichi Nomura512875b2007-12-13 14:15:25 +0000163 * Append an empty entry to catch sectors beyond the end of
164 * the device.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165 */
Jun'ichi Nomura512875b2007-12-13 14:15:25 +0000166 n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) +
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 sizeof(sector_t));
168 if (!n_highs)
169 return -ENOMEM;
170
171 n_targets = (struct dm_target *) (n_highs + num);
172
Mikulas Patocka57a2f232013-11-22 19:51:39 -0500173 memset(n_highs, -1, sizeof(*n_highs) * num);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 vfree(t->highs);
175
176 t->num_allocated = num;
177 t->highs = n_highs;
178 t->targets = n_targets;
179
180 return 0;
181}
182
Al Viroaeb5d722008-09-02 15:28:45 -0400183int dm_table_create(struct dm_table **result, fmode_t mode,
Mike Anderson1134e5a2006-03-27 01:17:54 -0800184 unsigned num_targets, struct mapped_device *md)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185{
Dmitry Monakhov094262d2007-10-19 22:38:51 +0100186 struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187
188 if (!t)
189 return -ENOMEM;
190
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 INIT_LIST_HEAD(&t->devices);
NeilBrown9d357b02011-01-13 20:00:01 +0000192 INIT_LIST_HEAD(&t->target_callbacks);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193
194 if (!num_targets)
195 num_targets = KEYS_PER_NODE;
196
197 num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
198
Mikulas Patocka5b2d0652013-11-22 19:52:06 -0500199 if (!num_targets) {
200 kfree(t);
201 return -ENOMEM;
202 }
203
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 if (alloc_targets(t, num_targets)) {
205 kfree(t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206 return -ENOMEM;
207 }
208
209 t->mode = mode;
Mike Anderson1134e5a2006-03-27 01:17:54 -0800210 t->md = md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 *result = t;
212 return 0;
213}
214
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500215static void free_devices(struct list_head *devices, struct mapped_device *md)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216{
217 struct list_head *tmp, *next;
218
Paul Jimenezafb24522008-02-08 02:09:59 +0000219 list_for_each_safe(tmp, next, devices) {
Mikulas Patocka82b15192008-10-10 13:37:09 +0100220 struct dm_dev_internal *dd =
221 list_entry(tmp, struct dm_dev_internal, list);
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500222 DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s",
223 dm_device_name(md), dd->dm_dev->name);
224 dm_put_table_device(md, dd->dm_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 kfree(dd);
226 }
227}
228
Mikulas Patockad5816872009-01-06 03:05:10 +0000229void dm_table_destroy(struct dm_table *t)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230{
231 unsigned int i;
232
Alasdair G Kergona7940152009-12-10 23:52:23 +0000233 if (!t)
234 return;
235
Will Drewry26803b92010-08-12 04:14:03 +0100236 /* free the indexes */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 if (t->depth >= 2)
238 vfree(t->index[t->depth - 2]);
239
240 /* free the targets */
241 for (i = 0; i < t->num_targets; i++) {
242 struct dm_target *tgt = t->targets + i;
243
244 if (tgt->type->dtr)
245 tgt->type->dtr(tgt);
246
247 dm_put_target_type(tgt->type);
248 }
249
250 vfree(t->highs);
251
252 /* free the device list */
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500253 free_devices(&t->devices, t->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100255 dm_free_md_mempools(t->mempools);
256
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 kfree(t);
258}
259
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 * See if we've already got a device in the list.
262 */
Mikulas Patocka82b15192008-10-10 13:37:09 +0100263static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264{
Mikulas Patocka82b15192008-10-10 13:37:09 +0100265 struct dm_dev_internal *dd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266
267 list_for_each_entry (dd, l, list)
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500268 if (dd->dm_dev->bdev->bd_dev == dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 return dd;
270
271 return NULL;
272}
273
274/*
Mikulas Patockaf6a1ed12009-09-04 20:40:22 +0100275 * If possible, this checks an area of a destination device is invalid.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 */
Mikulas Patockaf6a1ed12009-09-04 20:40:22 +0100277static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
278 sector_t start, sector_t len, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279{
Milan Brozf4808ca2011-05-29 13:02:52 +0100280 struct request_queue *q;
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100281 struct queue_limits *limits = data;
282 struct block_device *bdev = dev->bdev;
283 sector_t dev_size =
284 i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
Mike Snitzer02acc3a2009-06-22 10:12:30 +0100285 unsigned short logical_block_size_sectors =
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100286 limits->logical_block_size >> SECTOR_SHIFT;
Mike Snitzer02acc3a2009-06-22 10:12:30 +0100287 char b[BDEVNAME_SIZE];
Mike Anderson2cd54d92007-05-09 02:32:57 -0700288
Milan Brozf4808ca2011-05-29 13:02:52 +0100289 /*
290 * Some devices exist without request functions,
291 * such as loop devices not yet bound to backing files.
292 * Forbid the use of such devices.
293 */
294 q = bdev_get_queue(bdev);
295 if (!q || !q->make_request_fn) {
296 DMWARN("%s: %s is not yet initialised: "
297 "start=%llu, len=%llu, dev_size=%llu",
298 dm_device_name(ti->table->md), bdevname(bdev, b),
299 (unsigned long long)start,
300 (unsigned long long)len,
301 (unsigned long long)dev_size);
302 return 1;
303 }
304
Mike Anderson2cd54d92007-05-09 02:32:57 -0700305 if (!dev_size)
Mikulas Patockaf6a1ed12009-09-04 20:40:22 +0100306 return 0;
Mike Anderson2cd54d92007-05-09 02:32:57 -0700307
Mike Snitzer5dea2712009-07-23 20:30:42 +0100308 if ((start >= dev_size) || (start + len > dev_size)) {
Mike Snitzera963a952009-09-04 20:40:24 +0100309 DMWARN("%s: %s too small for target: "
310 "start=%llu, len=%llu, dev_size=%llu",
311 dm_device_name(ti->table->md), bdevname(bdev, b),
312 (unsigned long long)start,
313 (unsigned long long)len,
314 (unsigned long long)dev_size);
Mikulas Patockaf6a1ed12009-09-04 20:40:22 +0100315 return 1;
Mike Snitzer02acc3a2009-06-22 10:12:30 +0100316 }
317
318 if (logical_block_size_sectors <= 1)
Mikulas Patockaf6a1ed12009-09-04 20:40:22 +0100319 return 0;
Mike Snitzer02acc3a2009-06-22 10:12:30 +0100320
321 if (start & (logical_block_size_sectors - 1)) {
322 DMWARN("%s: start=%llu not aligned to h/w "
Mike Snitzera963a952009-09-04 20:40:24 +0100323 "logical block size %u of %s",
Mike Snitzer02acc3a2009-06-22 10:12:30 +0100324 dm_device_name(ti->table->md),
325 (unsigned long long)start,
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100326 limits->logical_block_size, bdevname(bdev, b));
Mikulas Patockaf6a1ed12009-09-04 20:40:22 +0100327 return 1;
Mike Snitzer02acc3a2009-06-22 10:12:30 +0100328 }
329
Mike Snitzer5dea2712009-07-23 20:30:42 +0100330 if (len & (logical_block_size_sectors - 1)) {
Mike Snitzer02acc3a2009-06-22 10:12:30 +0100331 DMWARN("%s: len=%llu not aligned to h/w "
Mike Snitzera963a952009-09-04 20:40:24 +0100332 "logical block size %u of %s",
Mike Snitzer02acc3a2009-06-22 10:12:30 +0100333 dm_device_name(ti->table->md),
Mike Snitzer5dea2712009-07-23 20:30:42 +0100334 (unsigned long long)len,
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100335 limits->logical_block_size, bdevname(bdev, b));
Mikulas Patockaf6a1ed12009-09-04 20:40:22 +0100336 return 1;
Mike Snitzer02acc3a2009-06-22 10:12:30 +0100337 }
338
Mikulas Patockaf6a1ed12009-09-04 20:40:22 +0100339 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340}
341
342/*
Alasdair G Kergon570b9d92009-04-02 19:55:28 +0100343 * This upgrades the mode on an already open dm_dev, being
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344 * careful to leave things as they were if we fail to reopen the
Alasdair G Kergon570b9d92009-04-02 19:55:28 +0100345 * device and not to touch the existing bdev field in case
346 * it is accessed concurrently inside dm_table_any_congested().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347 */
Al Viroaeb5d722008-09-02 15:28:45 -0400348static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
Mikulas Patocka82b15192008-10-10 13:37:09 +0100349 struct mapped_device *md)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350{
351 int r;
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500352 struct dm_dev *old_dev, *new_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500354 old_dev = dd->dm_dev;
Alasdair G Kergon570b9d92009-04-02 19:55:28 +0100355
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500356 r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev,
357 dd->dm_dev->mode | new_mode, &new_dev);
Alasdair G Kergon570b9d92009-04-02 19:55:28 +0100358 if (r)
359 return r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500361 dd->dm_dev = new_dev;
362 dm_put_table_device(md, old_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363
Alasdair G Kergon570b9d92009-04-02 19:55:28 +0100364 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365}
366
367/*
368 * Add a device to the list, or just increment the usage count if
369 * it's already present.
370 */
Mike Snitzer08649012011-08-02 12:32:04 +0100371int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
372 struct dm_dev **result)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373{
374 int r;
Andrew Morton69a2ce72008-02-08 02:10:14 +0000375 dev_t uninitialized_var(dev);
Mikulas Patocka82b15192008-10-10 13:37:09 +0100376 struct dm_dev_internal *dd;
Mike Snitzer08649012011-08-02 12:32:04 +0100377 struct dm_table *t = ti->table;
Dan Ehrenberg644bda62015-02-10 15:20:51 -0800378 struct block_device *bdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379
Eric Sesterhenn547bc922006-03-26 18:22:50 +0200380 BUG_ON(!t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381
Dan Ehrenberg644bda62015-02-10 15:20:51 -0800382 /* convert the path to a device */
383 bdev = lookup_bdev(path);
384 if (IS_ERR(bdev)) {
385 dev = name_to_dev_t(path);
386 if (!dev)
387 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 } else {
Christoph Hellwig72e82642008-08-11 00:24:08 +0200389 dev = bdev->bd_dev;
390 bdput(bdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 }
392
393 dd = find_device(&t->devices, dev);
394 if (!dd) {
395 dd = kmalloc(sizeof(*dd), GFP_KERNEL);
396 if (!dd)
397 return -ENOMEM;
398
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500399 if ((r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 kfree(dd);
401 return r;
402 }
403
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404 atomic_set(&dd->count, 0);
405 list_add(&dd->list, &t->devices);
406
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500407 } else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) {
Jun'ichi Nomuraf1659212006-03-27 01:17:59 -0800408 r = upgrade_mode(dd, mode, t->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 if (r)
410 return r;
411 }
412 atomic_inc(&dd->count);
413
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500414 *result = dd->dm_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 return 0;
416}
Mike Snitzer08649012011-08-02 12:32:04 +0100417EXPORT_SYMBOL(dm_get_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418
Mike Snitzer11f04312014-06-03 10:30:28 -0400419static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
420 sector_t start, sector_t len, void *data)
Bryn Reeves3cb40212006-10-03 01:15:42 -0700421{
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100422 struct queue_limits *limits = data;
423 struct block_device *bdev = dev->bdev;
Jens Axboe165125e2007-07-24 09:28:11 +0200424 struct request_queue *q = bdev_get_queue(bdev);
Alasdair G Kergon0c2322e2008-10-10 13:37:13 +0100425 char b[BDEVNAME_SIZE];
426
427 if (unlikely(!q)) {
428 DMWARN("%s: Cannot set limits for nonexistent device %s",
429 dm_device_name(ti->table->md), bdevname(bdev, b));
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100430 return 0;
Alasdair G Kergon0c2322e2008-10-10 13:37:13 +0100431 }
Bryn Reeves3cb40212006-10-03 01:15:42 -0700432
Martin K. Petersenb27d7f12010-01-11 03:21:50 -0500433 if (bdev_stack_limits(limits, bdev, start) < 0)
434 DMWARN("%s: adding target device %s caused an alignment inconsistency: "
Mike Snitzera963a952009-09-04 20:40:24 +0100435 "physical_block_size=%u, logical_block_size=%u, "
436 "alignment_offset=%u, start=%llu",
437 dm_device_name(ti->table->md), bdevname(bdev, b),
438 q->limits.physical_block_size,
439 q->limits.logical_block_size,
440 q->limits.alignment_offset,
Martin K. Petersenb27d7f12010-01-11 03:21:50 -0500441 (unsigned long long) start << SECTOR_SHIFT);
Bryn Reeves3cb40212006-10-03 01:15:42 -0700442
Milan Broz9980c632008-07-21 12:00:39 +0100443 /*
444 * Check if merge fn is supported.
445 * If not we'll force DM to use PAGE_SIZE or
446 * smaller I/O, just to be safe.
Bryn Reeves3cb40212006-10-03 01:15:42 -0700447 */
Mikulas Patockad5b9dd02011-08-02 12:32:04 +0100448 if (dm_queue_merge_is_compulsory(q) && !ti->type->merge)
Mike Snitzer72d4cd92010-12-17 08:34:20 +0100449 blk_limits_max_hw_sectors(limits,
450 (unsigned int) (PAGE_SIZE >> 9));
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100451 return 0;
Bryn Reeves3cb40212006-10-03 01:15:42 -0700452}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454/*
Mike Snitzer08649012011-08-02 12:32:04 +0100455 * Decrement a device's use count and remove it if necessary.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 */
Mikulas Patocka82b15192008-10-10 13:37:09 +0100457void dm_put_device(struct dm_target *ti, struct dm_dev *d)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458{
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500459 int found = 0;
460 struct list_head *devices = &ti->table->devices;
461 struct dm_dev_internal *dd;
Mikulas Patocka82b15192008-10-10 13:37:09 +0100462
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500463 list_for_each_entry(dd, devices, list) {
464 if (dd->dm_dev == d) {
465 found = 1;
466 break;
467 }
468 }
469 if (!found) {
470 DMWARN("%s: device %s not in table devices list",
471 dm_device_name(ti->table->md), d->name);
472 return;
473 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 if (atomic_dec_and_test(&dd->count)) {
Benjamin Marzinski86f11522014-08-13 13:53:43 -0500475 dm_put_table_device(ti->table->md, d);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 list_del(&dd->list);
477 kfree(dd);
478 }
479}
Mike Snitzer08649012011-08-02 12:32:04 +0100480EXPORT_SYMBOL(dm_put_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481
482/*
483 * Checks to see if the target joins onto the end of the table.
484 */
485static int adjoin(struct dm_table *table, struct dm_target *ti)
486{
487 struct dm_target *prev;
488
489 if (!table->num_targets)
490 return !ti->begin;
491
492 prev = &table->targets[table->num_targets - 1];
493 return (ti->begin == (prev->begin + prev->len));
494}
495
496/*
497 * Used to dynamically allocate the arg array.
Mikulas Patockaf36afb32013-10-31 13:55:45 -0400498 *
499 * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must
500 * process messages even if some device is suspended. These messages have a
501 * small fixed number of arguments.
502 *
503 * On the other hand, dm-switch needs to process bulk data using messages and
504 * excessive use of GFP_NOIO could cause trouble.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505 */
506static char **realloc_argv(unsigned *array_size, char **old_argv)
507{
508 char **argv;
509 unsigned new_size;
Mikulas Patockaf36afb32013-10-31 13:55:45 -0400510 gfp_t gfp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511
Mikulas Patockaf36afb32013-10-31 13:55:45 -0400512 if (*array_size) {
513 new_size = *array_size * 2;
514 gfp = GFP_KERNEL;
515 } else {
516 new_size = 8;
517 gfp = GFP_NOIO;
518 }
519 argv = kmalloc(new_size * sizeof(*argv), gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 if (argv) {
521 memcpy(argv, old_argv, *array_size * sizeof(*argv));
522 *array_size = new_size;
523 }
524
525 kfree(old_argv);
526 return argv;
527}
528
529/*
530 * Destructively splits up the argument list to pass to ctr.
531 */
532int dm_split_args(int *argc, char ***argvp, char *input)
533{
534 char *start, *end = input, *out, **argv = NULL;
535 unsigned array_size = 0;
536
537 *argc = 0;
David Teigland814d6862006-06-26 00:27:31 -0700538
539 if (!input) {
540 *argvp = NULL;
541 return 0;
542 }
543
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 argv = realloc_argv(&array_size, argv);
545 if (!argv)
546 return -ENOMEM;
547
548 while (1) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 /* Skip whitespace */
André Goddard Rosae7d28602009-12-14 18:01:06 -0800550 start = skip_spaces(end);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551
552 if (!*start)
553 break; /* success, we hit the end */
554
555 /* 'out' is used to remove any back-quotes */
556 end = out = start;
557 while (*end) {
558 /* Everything apart from '\0' can be quoted */
559 if (*end == '\\' && *(end + 1)) {
560 *out++ = *(end + 1);
561 end += 2;
562 continue;
563 }
564
565 if (isspace(*end))
566 break; /* end of token */
567
568 *out++ = *end++;
569 }
570
571 /* have we already filled the array ? */
572 if ((*argc + 1) > array_size) {
573 argv = realloc_argv(&array_size, argv);
574 if (!argv)
575 return -ENOMEM;
576 }
577
578 /* we know this is whitespace */
579 if (*end)
580 end++;
581
582 /* terminate the string and put it in the array */
583 *out = '\0';
584 argv[*argc] = start;
585 (*argc)++;
586 }
587
588 *argvp = argv;
589 return 0;
590}
591
Mike Snitzerbe6d4302009-06-22 10:12:31 +0100592/*
593 * Impose necessary and sufficient conditions on a devices's table such
594 * that any incoming bio which respects its logical_block_size can be
595 * processed successfully. If it falls across the boundary between
596 * two or more targets, the size of each piece it gets split into must
597 * be compatible with the logical_block_size of the target processing it.
598 */
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100599static int validate_hardware_logical_block_alignment(struct dm_table *table,
600 struct queue_limits *limits)
Mike Snitzerbe6d4302009-06-22 10:12:31 +0100601{
602 /*
603 * This function uses arithmetic modulo the logical_block_size
604 * (in units of 512-byte sectors).
605 */
606 unsigned short device_logical_block_size_sects =
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100607 limits->logical_block_size >> SECTOR_SHIFT;
Mike Snitzerbe6d4302009-06-22 10:12:31 +0100608
609 /*
610 * Offset of the start of the next table entry, mod logical_block_size.
611 */
612 unsigned short next_target_start = 0;
613
614 /*
615 * Given an aligned bio that extends beyond the end of a
616 * target, how many sectors must the next target handle?
617 */
618 unsigned short remaining = 0;
619
620 struct dm_target *uninitialized_var(ti);
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100621 struct queue_limits ti_limits;
Mike Snitzerbe6d4302009-06-22 10:12:31 +0100622 unsigned i = 0;
623
624 /*
625 * Check each entry in the table in turn.
626 */
627 while (i < dm_table_get_num_targets(table)) {
628 ti = dm_table_get_target(table, i++);
629
Martin K. Petersenb1bd0552012-01-11 16:27:11 +0100630 blk_set_stacking_limits(&ti_limits);
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100631
632 /* combine all target devices' limits */
633 if (ti->type->iterate_devices)
634 ti->type->iterate_devices(ti, dm_set_device_limits,
635 &ti_limits);
636
Mike Snitzerbe6d4302009-06-22 10:12:31 +0100637 /*
638 * If the remaining sectors fall entirely within this
639 * table entry are they compatible with its logical_block_size?
640 */
641 if (remaining < ti->len &&
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100642 remaining & ((ti_limits.logical_block_size >>
Mike Snitzerbe6d4302009-06-22 10:12:31 +0100643 SECTOR_SHIFT) - 1))
644 break; /* Error */
645
646 next_target_start =
647 (unsigned short) ((next_target_start + ti->len) &
648 (device_logical_block_size_sects - 1));
649 remaining = next_target_start ?
650 device_logical_block_size_sects - next_target_start : 0;
651 }
652
653 if (remaining) {
654 DMWARN("%s: table line %u (start sect %llu len %llu) "
Mike Snitzera963a952009-09-04 20:40:24 +0100655 "not aligned to h/w logical block size %u",
Mike Snitzerbe6d4302009-06-22 10:12:31 +0100656 dm_device_name(table->md), i,
657 (unsigned long long) ti->begin,
658 (unsigned long long) ti->len,
Mike Snitzer754c5fc2009-06-22 10:12:34 +0100659 limits->logical_block_size);
Mike Snitzerbe6d4302009-06-22 10:12:31 +0100660 return -EINVAL;
661 }
662
663 return 0;
664}
665
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666int dm_table_add_target(struct dm_table *t, const char *type,
667 sector_t start, sector_t len, char *params)
668{
669 int r = -EINVAL, argc;
670 char **argv;
671 struct dm_target *tgt;
672
Alasdair G Kergon3791e2f2011-10-31 20:19:00 +0000673 if (t->singleton) {
674 DMERR("%s: target type %s must appear alone in table",
675 dm_device_name(t->md), t->targets->type->name);
676 return -EINVAL;
677 }
678
Mikulas Patocka57a2f232013-11-22 19:51:39 -0500679 BUG_ON(t->num_targets >= t->num_allocated);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680
681 tgt = t->targets + t->num_targets;
682 memset(tgt, 0, sizeof(*tgt));
683
684 if (!len) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -0700685 DMERR("%s: zero-length target", dm_device_name(t->md));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 return -EINVAL;
687 }
688
689 tgt->type = dm_get_target_type(type);
690 if (!tgt->type) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -0700691 DMERR("%s: %s: unknown target type", dm_device_name(t->md),
692 type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693 return -EINVAL;
694 }
695
Alasdair G Kergon3791e2f2011-10-31 20:19:00 +0000696 if (dm_target_needs_singleton(tgt->type)) {
697 if (t->num_targets) {
698 DMERR("%s: target type %s must appear alone in table",
699 dm_device_name(t->md), type);
700 return -EINVAL;
701 }
702 t->singleton = 1;
703 }
704
Alasdair G Kergoncc6cbe12011-10-31 20:19:02 +0000705 if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) {
706 DMERR("%s: target type %s may not be included in read-only tables",
707 dm_device_name(t->md), type);
708 return -EINVAL;
709 }
710
Alasdair G Kergon36a04562011-10-31 20:19:04 +0000711 if (t->immutable_target_type) {
712 if (t->immutable_target_type != tgt->type) {
713 DMERR("%s: immutable target type %s cannot be mixed with other target types",
714 dm_device_name(t->md), t->immutable_target_type->name);
715 return -EINVAL;
716 }
717 } else if (dm_target_is_immutable(tgt->type)) {
718 if (t->num_targets) {
719 DMERR("%s: immutable target type %s cannot be mixed with other target types",
720 dm_device_name(t->md), tgt->type->name);
721 return -EINVAL;
722 }
723 t->immutable_target_type = tgt->type;
724 }
725
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 tgt->table = t;
727 tgt->begin = start;
728 tgt->len = len;
729 tgt->error = "Unknown error";
730
731 /*
732 * Does this target adjoin the previous one ?
733 */
734 if (!adjoin(t, tgt)) {
735 tgt->error = "Gap in table";
736 r = -EINVAL;
737 goto bad;
738 }
739
740 r = dm_split_args(&argc, &argv, params);
741 if (r) {
742 tgt->error = "couldn't split parameters (insufficient memory)";
743 goto bad;
744 }
745
746 r = tgt->type->ctr(tgt, argc, argv);
747 kfree(argv);
748 if (r)
749 goto bad;
750
751 t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
752
Alasdair G Kergon55a62ee2013-03-01 22:45:47 +0000753 if (!tgt->num_discard_bios && tgt->discards_supported)
754 DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
Mike Snitzer936688d2011-08-02 12:32:01 +0100755 dm_device_name(t->md), type);
Mike Snitzer5ae89a82010-08-12 04:14:08 +0100756
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 return 0;
758
759 bad:
Alasdair G Kergon72d94862006-06-26 00:27:35 -0700760 DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 dm_put_target_type(tgt->type);
762 return r;
763}
764
Mike Snitzer498f0102011-08-02 12:32:04 +0100765/*
766 * Target argument parsing helpers.
767 */
768static int validate_next_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
769 unsigned *value, char **error, unsigned grouped)
770{
771 const char *arg_str = dm_shift_arg(arg_set);
Mikulas Patocka31998ef2012-03-28 18:41:26 +0100772 char dummy;
Mike Snitzer498f0102011-08-02 12:32:04 +0100773
774 if (!arg_str ||
Mikulas Patocka31998ef2012-03-28 18:41:26 +0100775 (sscanf(arg_str, "%u%c", value, &dummy) != 1) ||
Mike Snitzer498f0102011-08-02 12:32:04 +0100776 (*value < arg->min) ||
777 (*value > arg->max) ||
778 (grouped && arg_set->argc < *value)) {
779 *error = arg->error;
780 return -EINVAL;
781 }
782
783 return 0;
784}
785
786int dm_read_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
787 unsigned *value, char **error)
788{
789 return validate_next_arg(arg, arg_set, value, error, 0);
790}
791EXPORT_SYMBOL(dm_read_arg);
792
793int dm_read_arg_group(struct dm_arg *arg, struct dm_arg_set *arg_set,
794 unsigned *value, char **error)
795{
796 return validate_next_arg(arg, arg_set, value, error, 1);
797}
798EXPORT_SYMBOL(dm_read_arg_group);
799
800const char *dm_shift_arg(struct dm_arg_set *as)
801{
802 char *r;
803
804 if (as->argc) {
805 as->argc--;
806 r = *as->argv;
807 as->argv++;
808 return r;
809 }
810
811 return NULL;
812}
813EXPORT_SYMBOL(dm_shift_arg);
814
815void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
816{
817 BUG_ON(as->argc < num_args);
818 as->argc -= num_args;
819 as->argv += num_args;
820}
821EXPORT_SYMBOL(dm_consume_args);
822
Junichi Nomura15b94a62015-05-29 08:51:03 +0000823static bool __table_type_request_based(unsigned table_type)
824{
825 return (table_type == DM_TYPE_REQUEST_BASED ||
826 table_type == DM_TYPE_MQ_REQUEST_BASED);
827}
828
Will Drewry26803b92010-08-12 04:14:03 +0100829static int dm_table_set_type(struct dm_table *t)
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100830{
831 unsigned i;
Mike Snitzer169e2cc2013-08-22 18:21:38 -0400832 unsigned bio_based = 0, request_based = 0, hybrid = 0;
Mike Snitzere5863d92014-12-17 21:08:12 -0500833 bool use_blk_mq = false;
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100834 struct dm_target *tgt;
835 struct dm_dev_internal *dd;
836 struct list_head *devices;
Mike Snitzer65803c22014-12-18 16:26:47 -0500837 unsigned live_md_type = dm_get_md_type(t->md);
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100838
839 for (i = 0; i < t->num_targets; i++) {
840 tgt = t->targets + i;
Mike Snitzer169e2cc2013-08-22 18:21:38 -0400841 if (dm_target_hybrid(tgt))
842 hybrid = 1;
843 else if (dm_target_request_based(tgt))
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100844 request_based = 1;
845 else
846 bio_based = 1;
847
848 if (bio_based && request_based) {
849 DMWARN("Inconsistent table: different target types"
850 " can't be mixed up");
851 return -EINVAL;
852 }
853 }
854
Mike Snitzer169e2cc2013-08-22 18:21:38 -0400855 if (hybrid && !bio_based && !request_based) {
856 /*
857 * The targets can work either way.
858 * Determine the type from the live device.
859 * Default to bio-based if device is new.
860 */
Junichi Nomura15b94a62015-05-29 08:51:03 +0000861 if (__table_type_request_based(live_md_type))
Mike Snitzer169e2cc2013-08-22 18:21:38 -0400862 request_based = 1;
863 else
864 bio_based = 1;
865 }
866
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100867 if (bio_based) {
868 /* We must use this table as bio-based */
869 t->type = DM_TYPE_BIO_BASED;
870 return 0;
871 }
872
873 BUG_ON(!request_based); /* No targets in this table */
874
Mike Snitzer65803c22014-12-18 16:26:47 -0500875 /*
876 * Request-based dm supports only tables that have a single target now.
877 * To support multiple targets, request splitting support is needed,
878 * and that needs lots of changes in the block-layer.
879 * (e.g. request completion process for partial completion.)
880 */
881 if (t->num_targets > 1) {
882 DMWARN("Request-based dm doesn't support multiple targets yet");
883 return -EINVAL;
884 }
885
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100886 /* Non-request-stackable devices can't be used for request-based dm */
887 devices = dm_table_get_devices(t);
888 list_for_each_entry(dd, devices, list) {
Mike Snitzere5863d92014-12-17 21:08:12 -0500889 struct request_queue *q = bdev_get_queue(dd->dm_dev->bdev);
890
891 if (!blk_queue_stackable(q)) {
892 DMERR("table load rejected: including"
893 " non-request-stackable devices");
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100894 return -EINVAL;
895 }
Mike Snitzere5863d92014-12-17 21:08:12 -0500896
897 if (q->mq_ops)
898 use_blk_mq = true;
899 }
900
901 if (use_blk_mq) {
902 /* verify _all_ devices in the table are blk-mq devices */
903 list_for_each_entry(dd, devices, list)
904 if (!bdev_get_queue(dd->dm_dev->bdev)->mq_ops) {
905 DMERR("table load rejected: not all devices"
906 " are blk-mq request-stackable");
907 return -EINVAL;
908 }
Mike Snitzer65803c22014-12-18 16:26:47 -0500909 t->type = DM_TYPE_MQ_REQUEST_BASED;
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100910
Junichi Nomura15b94a62015-05-29 08:51:03 +0000911 } else if (list_empty(devices) && __table_type_request_based(live_md_type)) {
Mike Snitzer65803c22014-12-18 16:26:47 -0500912 /* inherit live MD type */
913 t->type = live_md_type;
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100914
Mike Snitzer65803c22014-12-18 16:26:47 -0500915 } else
916 t->type = DM_TYPE_REQUEST_BASED;
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100917
918 return 0;
919}
920
921unsigned dm_table_get_type(struct dm_table *t)
922{
923 return t->type;
924}
925
Alasdair G Kergon36a04562011-10-31 20:19:04 +0000926struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
927{
928 return t->immutable_target_type;
929}
930
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100931bool dm_table_request_based(struct dm_table *t)
932{
Junichi Nomura15b94a62015-05-29 08:51:03 +0000933 return __table_type_request_based(dm_table_get_type(t));
Mike Snitzere5863d92014-12-17 21:08:12 -0500934}
935
936bool dm_table_mq_request_based(struct dm_table *t)
937{
938 return dm_table_get_type(t) == DM_TYPE_MQ_REQUEST_BASED;
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100939}
940
Mike Snitzer17e149b2015-03-11 15:01:09 -0400941static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100942{
943 unsigned type = dm_table_get_type(t);
Mikulas Patockac0820cf2012-12-21 20:23:38 +0000944 unsigned per_bio_data_size = 0;
Mike Snitzer78d8e582015-06-26 10:01:13 -0400945 struct dm_target *tgt;
Mikulas Patockac0820cf2012-12-21 20:23:38 +0000946 unsigned i;
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100947
Mike Snitzer78d8e582015-06-26 10:01:13 -0400948 if (unlikely(type == DM_TYPE_NONE)) {
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100949 DMWARN("no table type is set, can't allocate mempools");
950 return -EINVAL;
951 }
952
Mike Snitzer78d8e582015-06-26 10:01:13 -0400953 if (type == DM_TYPE_BIO_BASED)
954 for (i = 0; i < t->num_targets; i++) {
955 tgt = t->targets + i;
956 per_bio_data_size = max(per_bio_data_size, tgt->per_bio_data_size);
957 }
958
959 t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported, per_bio_data_size);
Mike Snitzer4e6e36c2015-06-26 09:42:57 -0400960 if (!t->mempools)
961 return -ENOMEM;
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +0100962
963 return 0;
964}
965
966void dm_table_free_md_mempools(struct dm_table *t)
967{
968 dm_free_md_mempools(t->mempools);
969 t->mempools = NULL;
970}
971
972struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
973{
974 return t->mempools;
975}
976
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977static int setup_indexes(struct dm_table *t)
978{
979 int i;
980 unsigned int total = 0;
981 sector_t *indexes;
982
983 /* allocate the space for *all* the indexes */
984 for (i = t->depth - 2; i >= 0; i--) {
985 t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
986 total += t->counts[i];
987 }
988
989 indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE);
990 if (!indexes)
991 return -ENOMEM;
992
993 /* set up internal nodes, bottom-up */
Jun'ichi Nomura82d601d2008-02-08 02:10:04 +0000994 for (i = t->depth - 2; i >= 0; i--) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 t->index[i] = indexes;
996 indexes += (KEYS_PER_NODE * t->counts[i]);
997 setup_btree_index(i, t);
998 }
999
1000 return 0;
1001}
1002
1003/*
1004 * Builds the btree to index the map.
1005 */
Will Drewry26803b92010-08-12 04:14:03 +01001006static int dm_table_build_index(struct dm_table *t)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007{
1008 int r = 0;
1009 unsigned int leaf_nodes;
1010
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 /* how many indexes will the btree have ? */
1012 leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
1013 t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
1014
1015 /* leaf layer has already been set up */
1016 t->counts[t->depth - 1] = leaf_nodes;
1017 t->index[t->depth - 1] = t->highs;
1018
1019 if (t->depth >= 2)
1020 r = setup_indexes(t);
1021
1022 return r;
1023}
1024
Will Drewry26803b92010-08-12 04:14:03 +01001025/*
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001026 * Get a disk whose integrity profile reflects the table's profile.
1027 * If %match_all is true, all devices' profiles must match.
1028 * If %match_all is false, all devices must at least have an
1029 * allocated integrity profile; but uninitialized is ok.
1030 * Returns NULL if integrity support was inconsistent or unavailable.
1031 */
1032static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t,
1033 bool match_all)
1034{
1035 struct list_head *devices = dm_table_get_devices(t);
1036 struct dm_dev_internal *dd = NULL;
1037 struct gendisk *prev_disk = NULL, *template_disk = NULL;
1038
1039 list_for_each_entry(dd, devices, list) {
Benjamin Marzinski86f11522014-08-13 13:53:43 -05001040 template_disk = dd->dm_dev->bdev->bd_disk;
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001041 if (!blk_get_integrity(template_disk))
1042 goto no_integrity;
1043 if (!match_all && !blk_integrity_is_initialized(template_disk))
1044 continue; /* skip uninitialized profiles */
1045 else if (prev_disk &&
1046 blk_integrity_compare(prev_disk, template_disk) < 0)
1047 goto no_integrity;
1048 prev_disk = template_disk;
1049 }
1050
1051 return template_disk;
1052
1053no_integrity:
1054 if (prev_disk)
1055 DMWARN("%s: integrity not set: %s and %s profile mismatch",
1056 dm_device_name(t->md),
1057 prev_disk->disk_name,
1058 template_disk->disk_name);
1059 return NULL;
1060}
1061
1062/*
Will Drewry26803b92010-08-12 04:14:03 +01001063 * Register the mapped device for blk_integrity support if
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001064 * the underlying devices have an integrity profile. But all devices
1065 * may not have matching profiles (checking all devices isn't reliable
1066 * during table load because this table may use other DM device(s) which
1067 * must be resumed before they will have an initialized integity profile).
1068 * Stacked DM devices force a 2 stage integrity profile validation:
1069 * 1 - during load, validate all initialized integrity profiles match
1070 * 2 - during resume, validate all integrity profiles match
Will Drewry26803b92010-08-12 04:14:03 +01001071 */
1072static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md)
1073{
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001074 struct gendisk *template_disk = NULL;
Will Drewry26803b92010-08-12 04:14:03 +01001075
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001076 template_disk = dm_table_get_integrity_disk(t, false);
1077 if (!template_disk)
1078 return 0;
Will Drewry26803b92010-08-12 04:14:03 +01001079
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001080 if (!blk_integrity_is_initialized(dm_disk(md))) {
1081 t->integrity_supported = 1;
1082 return blk_integrity_register(dm_disk(md), NULL);
1083 }
1084
1085 /*
1086 * If DM device already has an initalized integrity
1087 * profile the new profile should not conflict.
1088 */
1089 if (blk_integrity_is_initialized(template_disk) &&
1090 blk_integrity_compare(dm_disk(md), template_disk) < 0) {
1091 DMWARN("%s: conflict with existing integrity profile: "
1092 "%s profile mismatch",
1093 dm_device_name(t->md),
1094 template_disk->disk_name);
1095 return 1;
1096 }
1097
1098 /* Preserve existing initialized integrity profile */
1099 t->integrity_supported = 1;
Will Drewry26803b92010-08-12 04:14:03 +01001100 return 0;
1101}
1102
1103/*
1104 * Prepares the table for use by building the indices,
1105 * setting the type, and allocating mempools.
1106 */
1107int dm_table_complete(struct dm_table *t)
1108{
1109 int r;
1110
1111 r = dm_table_set_type(t);
1112 if (r) {
1113 DMERR("unable to set table type");
1114 return r;
1115 }
1116
1117 r = dm_table_build_index(t);
1118 if (r) {
1119 DMERR("unable to build btrees");
1120 return r;
1121 }
1122
1123 r = dm_table_prealloc_integrity(t, t->md);
1124 if (r) {
1125 DMERR("could not register integrity profile.");
1126 return r;
1127 }
1128
Mike Snitzer17e149b2015-03-11 15:01:09 -04001129 r = dm_table_alloc_md_mempools(t, t->md);
Will Drewry26803b92010-08-12 04:14:03 +01001130 if (r)
1131 DMERR("unable to allocate mempools");
1132
1133 return r;
1134}
1135
Arjan van de Ven48c9c272006-03-27 01:18:20 -08001136static DEFINE_MUTEX(_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137void dm_table_event_callback(struct dm_table *t,
1138 void (*fn)(void *), void *context)
1139{
Arjan van de Ven48c9c272006-03-27 01:18:20 -08001140 mutex_lock(&_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141 t->event_fn = fn;
1142 t->event_context = context;
Arjan van de Ven48c9c272006-03-27 01:18:20 -08001143 mutex_unlock(&_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001144}
1145
1146void dm_table_event(struct dm_table *t)
1147{
1148 /*
1149 * You can no longer call dm_table_event() from interrupt
1150 * context, use a bottom half instead.
1151 */
1152 BUG_ON(in_interrupt());
1153
Arjan van de Ven48c9c272006-03-27 01:18:20 -08001154 mutex_lock(&_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155 if (t->event_fn)
1156 t->event_fn(t->event_context);
Arjan van de Ven48c9c272006-03-27 01:18:20 -08001157 mutex_unlock(&_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158}
Mike Snitzer08649012011-08-02 12:32:04 +01001159EXPORT_SYMBOL(dm_table_event);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001160
1161sector_t dm_table_get_size(struct dm_table *t)
1162{
1163 return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
1164}
Mike Snitzer08649012011-08-02 12:32:04 +01001165EXPORT_SYMBOL(dm_table_get_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001166
1167struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
1168{
Milan Broz14353532006-06-26 00:27:27 -07001169 if (index >= t->num_targets)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001170 return NULL;
1171
1172 return t->targets + index;
1173}
1174
1175/*
1176 * Search the btree for the correct target.
Jun'ichi Nomura512875b2007-12-13 14:15:25 +00001177 *
1178 * Caller should check returned pointer with dm_target_is_valid()
1179 * to trap I/O beyond end of device.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180 */
1181struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
1182{
1183 unsigned int l, n = 0, k = 0;
1184 sector_t *node;
1185
1186 for (l = 0; l < t->depth; l++) {
1187 n = get_child(n, k);
1188 node = get_node(t, l, n);
1189
1190 for (k = 0; k < KEYS_PER_NODE; k++)
1191 if (node[k] >= sector)
1192 break;
1193 }
1194
1195 return &t->targets[(KEYS_PER_NODE * n) + k];
1196}
1197
Mike Snitzer3ae70652012-09-26 23:45:45 +01001198static int count_device(struct dm_target *ti, struct dm_dev *dev,
1199 sector_t start, sector_t len, void *data)
1200{
1201 unsigned *num_devices = data;
1202
1203 (*num_devices)++;
1204
1205 return 0;
1206}
1207
1208/*
1209 * Check whether a table has no data devices attached using each
1210 * target's iterate_devices method.
1211 * Returns false if the result is unknown because a target doesn't
1212 * support iterate_devices.
1213 */
1214bool dm_table_has_no_data_devices(struct dm_table *table)
1215{
1216 struct dm_target *uninitialized_var(ti);
1217 unsigned i = 0, num_devices = 0;
1218
1219 while (i < dm_table_get_num_targets(table)) {
1220 ti = dm_table_get_target(table, i++);
1221
1222 if (!ti->type->iterate_devices)
1223 return false;
1224
1225 ti->type->iterate_devices(ti, count_device, &num_devices);
1226 if (num_devices)
1227 return false;
1228 }
1229
1230 return true;
1231}
1232
Martin K. Petersen9c470082009-04-09 00:27:12 +01001233/*
Mike Snitzer754c5fc2009-06-22 10:12:34 +01001234 * Establish the new table's queue_limits and validate them.
1235 */
1236int dm_calculate_queue_limits(struct dm_table *table,
1237 struct queue_limits *limits)
1238{
1239 struct dm_target *uninitialized_var(ti);
1240 struct queue_limits ti_limits;
1241 unsigned i = 0;
1242
Martin K. Petersenb1bd0552012-01-11 16:27:11 +01001243 blk_set_stacking_limits(limits);
Mike Snitzer754c5fc2009-06-22 10:12:34 +01001244
1245 while (i < dm_table_get_num_targets(table)) {
Martin K. Petersenb1bd0552012-01-11 16:27:11 +01001246 blk_set_stacking_limits(&ti_limits);
Mike Snitzer754c5fc2009-06-22 10:12:34 +01001247
1248 ti = dm_table_get_target(table, i++);
1249
1250 if (!ti->type->iterate_devices)
1251 goto combine_limits;
1252
1253 /*
1254 * Combine queue limits of all the devices this target uses.
1255 */
1256 ti->type->iterate_devices(ti, dm_set_device_limits,
1257 &ti_limits);
1258
Mike Snitzer40bea432009-09-04 20:40:25 +01001259 /* Set I/O hints portion of queue limits */
1260 if (ti->type->io_hints)
1261 ti->type->io_hints(ti, &ti_limits);
1262
Mike Snitzer754c5fc2009-06-22 10:12:34 +01001263 /*
1264 * Check each device area is consistent with the target's
1265 * overall queue limits.
1266 */
Mikulas Patockaf6a1ed12009-09-04 20:40:22 +01001267 if (ti->type->iterate_devices(ti, device_area_is_invalid,
1268 &ti_limits))
Mike Snitzer754c5fc2009-06-22 10:12:34 +01001269 return -EINVAL;
1270
1271combine_limits:
1272 /*
1273 * Merge this target's queue limits into the overall limits
1274 * for the table.
1275 */
1276 if (blk_stack_limits(limits, &ti_limits, 0) < 0)
Martin K. Petersenb27d7f12010-01-11 03:21:50 -05001277 DMWARN("%s: adding target device "
Mike Snitzer754c5fc2009-06-22 10:12:34 +01001278 "(start sect %llu len %llu) "
Martin K. Petersenb27d7f12010-01-11 03:21:50 -05001279 "caused an alignment inconsistency",
Mike Snitzer754c5fc2009-06-22 10:12:34 +01001280 dm_device_name(table->md),
1281 (unsigned long long) ti->begin,
1282 (unsigned long long) ti->len);
1283 }
1284
1285 return validate_hardware_logical_block_alignment(table, limits);
1286}
1287
1288/*
Martin K. Petersen9c470082009-04-09 00:27:12 +01001289 * Set the integrity profile for this device if all devices used have
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001290 * matching profiles. We're quite deep in the resume path but still
1291 * don't know if all devices (particularly DM devices this device
1292 * may be stacked on) have matching profiles. Even if the profiles
1293 * don't match we have no way to fail (to resume) at this point.
Martin K. Petersen9c470082009-04-09 00:27:12 +01001294 */
1295static void dm_table_set_integrity(struct dm_table *t)
1296{
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001297 struct gendisk *template_disk = NULL;
Martin K. Petersen9c470082009-04-09 00:27:12 +01001298
1299 if (!blk_get_integrity(dm_disk(t->md)))
1300 return;
1301
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001302 template_disk = dm_table_get_integrity_disk(t, true);
Mike Snitzer876fbba2011-09-25 23:26:17 +01001303 if (template_disk)
1304 blk_integrity_register(dm_disk(t->md),
1305 blk_get_integrity(template_disk));
1306 else if (blk_integrity_is_initialized(dm_disk(t->md)))
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001307 DMWARN("%s: device no longer has a valid integrity profile",
1308 dm_device_name(t->md));
Mike Snitzer876fbba2011-09-25 23:26:17 +01001309 else
1310 DMWARN("%s: unable to establish an integrity profile",
1311 dm_device_name(t->md));
Martin K. Petersen9c470082009-04-09 00:27:12 +01001312}
1313
Mike Snitzered8b7522011-08-02 12:32:08 +01001314static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
1315 sector_t start, sector_t len, void *data)
1316{
1317 unsigned flush = (*(unsigned *)data);
1318 struct request_queue *q = bdev_get_queue(dev->bdev);
1319
1320 return q && (q->flush_flags & flush);
1321}
1322
1323static bool dm_table_supports_flush(struct dm_table *t, unsigned flush)
1324{
1325 struct dm_target *ti;
1326 unsigned i = 0;
1327
1328 /*
1329 * Require at least one underlying device to support flushes.
1330 * t->devices includes internal dm devices such as mirror logs
1331 * so we need to use iterate_devices here, which targets
1332 * supporting flushes must provide.
1333 */
1334 while (i < dm_table_get_num_targets(t)) {
1335 ti = dm_table_get_target(t, i++);
1336
Alasdair G Kergon55a62ee2013-03-01 22:45:47 +00001337 if (!ti->num_flush_bios)
Mike Snitzered8b7522011-08-02 12:32:08 +01001338 continue;
1339
Joe Thornber0e9c24e2012-07-27 15:08:07 +01001340 if (ti->flush_supported)
Joe Perches7f61f5a2015-03-30 10:43:18 -07001341 return true;
Joe Thornber0e9c24e2012-07-27 15:08:07 +01001342
Mike Snitzered8b7522011-08-02 12:32:08 +01001343 if (ti->type->iterate_devices &&
1344 ti->type->iterate_devices(ti, device_flush_capable, &flush))
Joe Perches7f61f5a2015-03-30 10:43:18 -07001345 return true;
Mike Snitzered8b7522011-08-02 12:32:08 +01001346 }
1347
Joe Perches7f61f5a2015-03-30 10:43:18 -07001348 return false;
Mike Snitzered8b7522011-08-02 12:32:08 +01001349}
1350
Milan Broz983c7db2011-09-25 23:26:21 +01001351static bool dm_table_discard_zeroes_data(struct dm_table *t)
1352{
1353 struct dm_target *ti;
1354 unsigned i = 0;
1355
1356 /* Ensure that all targets supports discard_zeroes_data. */
1357 while (i < dm_table_get_num_targets(t)) {
1358 ti = dm_table_get_target(t, i++);
1359
1360 if (ti->discard_zeroes_data_unsupported)
Joe Perches7f61f5a2015-03-30 10:43:18 -07001361 return false;
Milan Broz983c7db2011-09-25 23:26:21 +01001362 }
1363
Joe Perches7f61f5a2015-03-30 10:43:18 -07001364 return true;
Milan Broz983c7db2011-09-25 23:26:21 +01001365}
1366
Mandeep Singh Baines4693c9662011-10-31 20:18:50 +00001367static int device_is_nonrot(struct dm_target *ti, struct dm_dev *dev,
1368 sector_t start, sector_t len, void *data)
1369{
1370 struct request_queue *q = bdev_get_queue(dev->bdev);
1371
1372 return q && blk_queue_nonrot(q);
1373}
1374
Milan Brozc3c4555e2012-09-26 23:45:43 +01001375static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev,
1376 sector_t start, sector_t len, void *data)
1377{
1378 struct request_queue *q = bdev_get_queue(dev->bdev);
1379
1380 return q && !blk_queue_add_random(q);
1381}
1382
Jeff Moyer200612e2014-08-08 11:03:41 -04001383static int queue_supports_sg_merge(struct dm_target *ti, struct dm_dev *dev,
1384 sector_t start, sector_t len, void *data)
1385{
1386 struct request_queue *q = bdev_get_queue(dev->bdev);
1387
1388 return q && !test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags);
1389}
1390
Keith Buscha4afe762015-01-24 15:10:49 -07001391static int queue_supports_sg_gaps(struct dm_target *ti, struct dm_dev *dev,
1392 sector_t start, sector_t len, void *data)
1393{
1394 struct request_queue *q = bdev_get_queue(dev->bdev);
1395
1396 return q && !test_bit(QUEUE_FLAG_SG_GAPS, &q->queue_flags);
1397}
1398
Milan Brozc3c4555e2012-09-26 23:45:43 +01001399static bool dm_table_all_devices_attribute(struct dm_table *t,
1400 iterate_devices_callout_fn func)
Mandeep Singh Baines4693c9662011-10-31 20:18:50 +00001401{
1402 struct dm_target *ti;
1403 unsigned i = 0;
1404
Mandeep Singh Baines4693c9662011-10-31 20:18:50 +00001405 while (i < dm_table_get_num_targets(t)) {
1406 ti = dm_table_get_target(t, i++);
1407
1408 if (!ti->type->iterate_devices ||
Milan Brozc3c4555e2012-09-26 23:45:43 +01001409 !ti->type->iterate_devices(ti, func, NULL))
Joe Perches7f61f5a2015-03-30 10:43:18 -07001410 return false;
Mandeep Singh Baines4693c9662011-10-31 20:18:50 +00001411 }
1412
Joe Perches7f61f5a2015-03-30 10:43:18 -07001413 return true;
Mandeep Singh Baines4693c9662011-10-31 20:18:50 +00001414}
1415
Mike Snitzerd54eaa52012-12-21 20:23:36 +00001416static int device_not_write_same_capable(struct dm_target *ti, struct dm_dev *dev,
1417 sector_t start, sector_t len, void *data)
1418{
1419 struct request_queue *q = bdev_get_queue(dev->bdev);
1420
1421 return q && !q->limits.max_write_same_sectors;
1422}
1423
1424static bool dm_table_supports_write_same(struct dm_table *t)
1425{
1426 struct dm_target *ti;
1427 unsigned i = 0;
1428
1429 while (i < dm_table_get_num_targets(t)) {
1430 ti = dm_table_get_target(t, i++);
1431
Alasdair G Kergon55a62ee2013-03-01 22:45:47 +00001432 if (!ti->num_write_same_bios)
Mike Snitzerd54eaa52012-12-21 20:23:36 +00001433 return false;
1434
1435 if (!ti->type->iterate_devices ||
Mike Snitzerdc019b22013-05-10 14:37:16 +01001436 ti->type->iterate_devices(ti, device_not_write_same_capable, NULL))
Mike Snitzerd54eaa52012-12-21 20:23:36 +00001437 return false;
1438 }
1439
1440 return true;
1441}
1442
Mikulas Patockaa7ffb6a2014-07-10 12:23:07 -04001443static int device_discard_capable(struct dm_target *ti, struct dm_dev *dev,
1444 sector_t start, sector_t len, void *data)
1445{
1446 struct request_queue *q = bdev_get_queue(dev->bdev);
1447
1448 return q && blk_queue_discard(q);
1449}
1450
1451static bool dm_table_supports_discards(struct dm_table *t)
1452{
1453 struct dm_target *ti;
1454 unsigned i = 0;
1455
1456 /*
1457 * Unless any target used by the table set discards_supported,
1458 * require at least one underlying device to support discards.
1459 * t->devices includes internal dm devices such as mirror logs
1460 * so we need to use iterate_devices here, which targets
1461 * supporting discard selectively must provide.
1462 */
1463 while (i < dm_table_get_num_targets(t)) {
1464 ti = dm_table_get_target(t, i++);
1465
1466 if (!ti->num_discard_bios)
1467 continue;
1468
1469 if (ti->discards_supported)
Joe Perches7f61f5a2015-03-30 10:43:18 -07001470 return true;
Mikulas Patockaa7ffb6a2014-07-10 12:23:07 -04001471
1472 if (ti->type->iterate_devices &&
1473 ti->type->iterate_devices(ti, device_discard_capable, NULL))
Joe Perches7f61f5a2015-03-30 10:43:18 -07001474 return true;
Mikulas Patockaa7ffb6a2014-07-10 12:23:07 -04001475 }
1476
Joe Perches7f61f5a2015-03-30 10:43:18 -07001477 return false;
Mikulas Patockaa7ffb6a2014-07-10 12:23:07 -04001478}
1479
Mike Snitzer754c5fc2009-06-22 10:12:34 +01001480void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
1481 struct queue_limits *limits)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482{
Mike Snitzered8b7522011-08-02 12:32:08 +01001483 unsigned flush = 0;
1484
Linus Torvalds1da177e2005-04-16 15:20:36 -07001485 /*
Mike Snitzer11977642009-06-22 10:12:32 +01001486 * Copy table's limits to the DM device's request_queue
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487 */
Mike Snitzer754c5fc2009-06-22 10:12:34 +01001488 q->limits = *limits;
Jens Axboec9a3f6d2008-04-29 19:12:35 +02001489
Mike Snitzer5ae89a82010-08-12 04:14:08 +01001490 if (!dm_table_supports_discards(t))
1491 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
1492 else
1493 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
1494
Mike Snitzered8b7522011-08-02 12:32:08 +01001495 if (dm_table_supports_flush(t, REQ_FLUSH)) {
1496 flush |= REQ_FLUSH;
1497 if (dm_table_supports_flush(t, REQ_FUA))
1498 flush |= REQ_FUA;
1499 }
1500 blk_queue_flush(q, flush);
1501
Milan Broz983c7db2011-09-25 23:26:21 +01001502 if (!dm_table_discard_zeroes_data(t))
1503 q->limits.discard_zeroes_data = 0;
1504
Milan Brozc3c4555e2012-09-26 23:45:43 +01001505 /* Ensure that all underlying devices are non-rotational. */
1506 if (dm_table_all_devices_attribute(t, device_is_nonrot))
Mandeep Singh Baines4693c9662011-10-31 20:18:50 +00001507 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
1508 else
1509 queue_flag_clear_unlocked(QUEUE_FLAG_NONROT, q);
1510
Mike Snitzerd54eaa52012-12-21 20:23:36 +00001511 if (!dm_table_supports_write_same(t))
1512 q->limits.max_write_same_sectors = 0;
Mike Snitzerc1a94672012-12-21 20:23:30 +00001513
Jeff Moyer200612e2014-08-08 11:03:41 -04001514 if (dm_table_all_devices_attribute(t, queue_supports_sg_merge))
1515 queue_flag_clear_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);
1516 else
1517 queue_flag_set_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);
1518
Keith Buscha4afe762015-01-24 15:10:49 -07001519 if (dm_table_all_devices_attribute(t, queue_supports_sg_gaps))
1520 queue_flag_clear_unlocked(QUEUE_FLAG_SG_GAPS, q);
1521 else
1522 queue_flag_set_unlocked(QUEUE_FLAG_SG_GAPS, q);
1523
Martin K. Petersen9c470082009-04-09 00:27:12 +01001524 dm_table_set_integrity(t);
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +01001525
1526 /*
Milan Brozc3c4555e2012-09-26 23:45:43 +01001527 * Determine whether or not this queue's I/O timings contribute
1528 * to the entropy pool, Only request-based targets use this.
1529 * Clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not
1530 * have it set.
1531 */
1532 if (blk_queue_add_random(q) && dm_table_all_devices_attribute(t, device_is_not_random))
1533 queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, q);
1534
1535 /*
Kiyoshi Uedae6ee8c02009-06-22 10:12:36 +01001536 * QUEUE_FLAG_STACKABLE must be set after all queue settings are
1537 * visible to other CPUs because, once the flag is set, incoming bios
1538 * are processed by request-based dm, which refers to the queue
1539 * settings.
1540 * Until the flag set, bios are passed to bio-based dm and queued to
1541 * md->deferred where queue settings are not needed yet.
1542 * Those bios are passed to request-based dm at the resume time.
1543 */
1544 smp_mb();
1545 if (dm_table_request_based(t))
1546 queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, q);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001547}
1548
1549unsigned int dm_table_get_num_targets(struct dm_table *t)
1550{
1551 return t->num_targets;
1552}
1553
1554struct list_head *dm_table_get_devices(struct dm_table *t)
1555{
1556 return &t->devices;
1557}
1558
Al Viroaeb5d722008-09-02 15:28:45 -04001559fmode_t dm_table_get_mode(struct dm_table *t)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001560{
1561 return t->mode;
1562}
Mike Snitzer08649012011-08-02 12:32:04 +01001563EXPORT_SYMBOL(dm_table_get_mode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001564
Mike Snitzerd67ee212014-10-28 20:13:31 -04001565enum suspend_mode {
1566 PRESUSPEND,
1567 PRESUSPEND_UNDO,
1568 POSTSUSPEND,
1569};
1570
1571static void suspend_targets(struct dm_table *t, enum suspend_mode mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001572{
1573 int i = t->num_targets;
1574 struct dm_target *ti = t->targets;
1575
1576 while (i--) {
Mike Snitzerd67ee212014-10-28 20:13:31 -04001577 switch (mode) {
1578 case PRESUSPEND:
1579 if (ti->type->presuspend)
1580 ti->type->presuspend(ti);
1581 break;
1582 case PRESUSPEND_UNDO:
1583 if (ti->type->presuspend_undo)
1584 ti->type->presuspend_undo(ti);
1585 break;
1586 case POSTSUSPEND:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001587 if (ti->type->postsuspend)
1588 ti->type->postsuspend(ti);
Mike Snitzerd67ee212014-10-28 20:13:31 -04001589 break;
1590 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001591 ti++;
1592 }
1593}
1594
1595void dm_table_presuspend_targets(struct dm_table *t)
1596{
Alasdair G Kergoncf222b32005-07-28 21:15:57 -07001597 if (!t)
1598 return;
1599
Mike Snitzerd67ee212014-10-28 20:13:31 -04001600 suspend_targets(t, PRESUSPEND);
1601}
1602
1603void dm_table_presuspend_undo_targets(struct dm_table *t)
1604{
1605 if (!t)
1606 return;
1607
1608 suspend_targets(t, PRESUSPEND_UNDO);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001609}
1610
1611void dm_table_postsuspend_targets(struct dm_table *t)
1612{
Alasdair G Kergoncf222b32005-07-28 21:15:57 -07001613 if (!t)
1614 return;
1615
Mike Snitzerd67ee212014-10-28 20:13:31 -04001616 suspend_targets(t, POSTSUSPEND);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001617}
1618
Milan Broz8757b772006-10-03 01:15:36 -07001619int dm_table_resume_targets(struct dm_table *t)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620{
Milan Broz8757b772006-10-03 01:15:36 -07001621 int i, r = 0;
1622
1623 for (i = 0; i < t->num_targets; i++) {
1624 struct dm_target *ti = t->targets + i;
1625
1626 if (!ti->type->preresume)
1627 continue;
1628
1629 r = ti->type->preresume(ti);
Mike Snitzer7833b082013-10-24 14:10:29 -04001630 if (r) {
1631 DMERR("%s: %s: preresume failed, error = %d",
1632 dm_device_name(t->md), ti->type->name, r);
Milan Broz8757b772006-10-03 01:15:36 -07001633 return r;
Mike Snitzer7833b082013-10-24 14:10:29 -04001634 }
Milan Broz8757b772006-10-03 01:15:36 -07001635 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001636
1637 for (i = 0; i < t->num_targets; i++) {
1638 struct dm_target *ti = t->targets + i;
1639
1640 if (ti->type->resume)
1641 ti->type->resume(ti);
1642 }
Milan Broz8757b772006-10-03 01:15:36 -07001643
1644 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001645}
1646
NeilBrown9d357b02011-01-13 20:00:01 +00001647void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb)
1648{
1649 list_add(&cb->list, &t->target_callbacks);
1650}
1651EXPORT_SYMBOL_GPL(dm_table_add_target_callbacks);
1652
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653int dm_table_any_congested(struct dm_table *t, int bdi_bits)
1654{
Mikulas Patocka82b15192008-10-10 13:37:09 +01001655 struct dm_dev_internal *dd;
Paul Jimenezafb24522008-02-08 02:09:59 +00001656 struct list_head *devices = dm_table_get_devices(t);
NeilBrown9d357b02011-01-13 20:00:01 +00001657 struct dm_target_callbacks *cb;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001658 int r = 0;
1659
Paul Jimenezafb24522008-02-08 02:09:59 +00001660 list_for_each_entry(dd, devices, list) {
Benjamin Marzinski86f11522014-08-13 13:53:43 -05001661 struct request_queue *q = bdev_get_queue(dd->dm_dev->bdev);
Alasdair G Kergon0c2322e2008-10-10 13:37:13 +01001662 char b[BDEVNAME_SIZE];
1663
1664 if (likely(q))
1665 r |= bdi_congested(&q->backing_dev_info, bdi_bits);
1666 else
1667 DMWARN_LIMIT("%s: any_congested: nonexistent device %s",
1668 dm_device_name(t->md),
Benjamin Marzinski86f11522014-08-13 13:53:43 -05001669 bdevname(dd->dm_dev->bdev, b));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001670 }
1671
NeilBrown9d357b02011-01-13 20:00:01 +00001672 list_for_each_entry(cb, &t->target_callbacks, list)
1673 if (cb->congested_fn)
1674 r |= cb->congested_fn(cb, bdi_bits);
1675
Linus Torvalds1da177e2005-04-16 15:20:36 -07001676 return r;
1677}
1678
Mike Anderson1134e5a2006-03-27 01:17:54 -08001679struct mapped_device *dm_table_get_md(struct dm_table *t)
1680{
Mike Anderson1134e5a2006-03-27 01:17:54 -08001681 return t->md;
1682}
Mike Snitzer08649012011-08-02 12:32:04 +01001683EXPORT_SYMBOL(dm_table_get_md);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001684
Mike Snitzer9974fa22014-02-28 15:33:43 +01001685void dm_table_run_md_queue_async(struct dm_table *t)
1686{
1687 struct mapped_device *md;
1688 struct request_queue *queue;
1689 unsigned long flags;
1690
1691 if (!dm_table_request_based(t))
1692 return;
1693
1694 md = dm_table_get_md(t);
1695 queue = dm_get_md_queue(md);
1696 if (queue) {
Mike Snitzerbfebd1c2015-03-08 00:51:47 -05001697 if (queue->mq_ops)
1698 blk_mq_run_hw_queues(queue, true);
1699 else {
1700 spin_lock_irqsave(queue->queue_lock, flags);
1701 blk_run_queue_async(queue);
1702 spin_unlock_irqrestore(queue->queue_lock, flags);
1703 }
Mike Snitzer9974fa22014-02-28 15:33:43 +01001704 }
1705}
1706EXPORT_SYMBOL(dm_table_run_md_queue_async);
1707