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Philipp Reisnerb411b362009-09-25 16:07:19 -07001/*
2 drbd.c
3
4 This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
5
6 Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
7 Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>.
8 Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.
9
10 Thanks to Carter Burden, Bart Grantham and Gennadiy Nerubayev
11 from Logicworks, Inc. for making SDP replication support possible.
12
13 drbd is free software; you can redistribute it and/or modify
14 it under the terms of the GNU General Public License as published by
15 the Free Software Foundation; either version 2, or (at your option)
16 any later version.
17
18 drbd is distributed in the hope that it will be useful,
19 but WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 GNU General Public License for more details.
22
23 You should have received a copy of the GNU General Public License
24 along with drbd; see the file COPYING. If not, write to
25 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
26
27 */
28
Philipp Reisnerb411b362009-09-25 16:07:19 -070029#include <linux/module.h>
Philipp Reisnerb411b362009-09-25 16:07:19 -070030#include <linux/drbd.h>
31#include <asm/uaccess.h>
32#include <asm/types.h>
33#include <net/sock.h>
34#include <linux/ctype.h>
35#include <linux/smp_lock.h>
36#include <linux/fs.h>
37#include <linux/file.h>
38#include <linux/proc_fs.h>
39#include <linux/init.h>
40#include <linux/mm.h>
41#include <linux/memcontrol.h>
42#include <linux/mm_inline.h>
43#include <linux/slab.h>
44#include <linux/random.h>
45#include <linux/reboot.h>
46#include <linux/notifier.h>
47#include <linux/kthread.h>
48
49#define __KERNEL_SYSCALLS__
50#include <linux/unistd.h>
51#include <linux/vmalloc.h>
52
53#include <linux/drbd_limits.h>
54#include "drbd_int.h"
Philipp Reisnerb411b362009-09-25 16:07:19 -070055#include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */
56
57#include "drbd_vli.h"
58
59struct after_state_chg_work {
60 struct drbd_work w;
61 union drbd_state os;
62 union drbd_state ns;
63 enum chg_state_flags flags;
64 struct completion *done;
65};
66
67int drbdd_init(struct drbd_thread *);
68int drbd_worker(struct drbd_thread *);
69int drbd_asender(struct drbd_thread *);
70
71int drbd_init(void);
72static int drbd_open(struct block_device *bdev, fmode_t mode);
73static int drbd_release(struct gendisk *gd, fmode_t mode);
74static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused);
75static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
76 union drbd_state ns, enum chg_state_flags flags);
77static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused);
78static void md_sync_timer_fn(unsigned long data);
79static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused);
80
Philipp Reisnerb411b362009-09-25 16:07:19 -070081MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, "
82 "Lars Ellenberg <lars@linbit.com>");
83MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION);
84MODULE_VERSION(REL_VERSION);
85MODULE_LICENSE("GPL");
86MODULE_PARM_DESC(minor_count, "Maximum number of drbd devices (1-255)");
87MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR);
88
89#include <linux/moduleparam.h>
90/* allow_open_on_secondary */
91MODULE_PARM_DESC(allow_oos, "DONT USE!");
92/* thanks to these macros, if compiled into the kernel (not-module),
93 * this becomes the boot parameter drbd.minor_count */
94module_param(minor_count, uint, 0444);
95module_param(disable_sendpage, bool, 0644);
96module_param(allow_oos, bool, 0);
97module_param(cn_idx, uint, 0444);
98module_param(proc_details, int, 0644);
99
100#ifdef CONFIG_DRBD_FAULT_INJECTION
101int enable_faults;
102int fault_rate;
103static int fault_count;
104int fault_devs;
105/* bitmap of enabled faults */
106module_param(enable_faults, int, 0664);
107/* fault rate % value - applies to all enabled faults */
108module_param(fault_rate, int, 0664);
109/* count of faults inserted */
110module_param(fault_count, int, 0664);
111/* bitmap of devices to insert faults on */
112module_param(fault_devs, int, 0644);
113#endif
114
115/* module parameter, defined */
116unsigned int minor_count = 32;
117int disable_sendpage;
118int allow_oos;
119unsigned int cn_idx = CN_IDX_DRBD;
120int proc_details; /* Detail level in proc drbd*/
121
122/* Module parameter for setting the user mode helper program
123 * to run. Default is /sbin/drbdadm */
124char usermode_helper[80] = "/sbin/drbdadm";
125
126module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644);
127
128/* in 2.6.x, our device mapping and config info contains our virtual gendisks
129 * as member "struct gendisk *vdisk;"
130 */
131struct drbd_conf **minor_table;
132
133struct kmem_cache *drbd_request_cache;
134struct kmem_cache *drbd_ee_cache; /* epoch entries */
135struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */
136struct kmem_cache *drbd_al_ext_cache; /* activity log extents */
137mempool_t *drbd_request_mempool;
138mempool_t *drbd_ee_mempool;
139
140/* I do not use a standard mempool, because:
141 1) I want to hand out the pre-allocated objects first.
142 2) I want to be able to interrupt sleeping allocation with a signal.
143 Note: This is a single linked list, the next pointer is the private
144 member of struct page.
145 */
146struct page *drbd_pp_pool;
147spinlock_t drbd_pp_lock;
148int drbd_pp_vacant;
149wait_queue_head_t drbd_pp_wait;
150
151DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5);
152
Emese Revfy7d4e9d02009-12-14 00:59:30 +0100153static const struct block_device_operations drbd_ops = {
Philipp Reisnerb411b362009-09-25 16:07:19 -0700154 .owner = THIS_MODULE,
155 .open = drbd_open,
156 .release = drbd_release,
157};
158
159#define ARRY_SIZE(A) (sizeof(A)/sizeof(A[0]))
160
161#ifdef __CHECKER__
162/* When checking with sparse, and this is an inline function, sparse will
163 give tons of false positives. When this is a real functions sparse works.
164 */
165int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
166{
167 int io_allowed;
168
169 atomic_inc(&mdev->local_cnt);
170 io_allowed = (mdev->state.disk >= mins);
171 if (!io_allowed) {
172 if (atomic_dec_and_test(&mdev->local_cnt))
173 wake_up(&mdev->misc_wait);
174 }
175 return io_allowed;
176}
177
178#endif
179
180/**
181 * DOC: The transfer log
182 *
183 * The transfer log is a single linked list of &struct drbd_tl_epoch objects.
184 * mdev->newest_tle points to the head, mdev->oldest_tle points to the tail
185 * of the list. There is always at least one &struct drbd_tl_epoch object.
186 *
187 * Each &struct drbd_tl_epoch has a circular double linked list of requests
188 * attached.
189 */
190static int tl_init(struct drbd_conf *mdev)
191{
192 struct drbd_tl_epoch *b;
193
194 /* during device minor initialization, we may well use GFP_KERNEL */
195 b = kmalloc(sizeof(struct drbd_tl_epoch), GFP_KERNEL);
196 if (!b)
197 return 0;
198 INIT_LIST_HEAD(&b->requests);
199 INIT_LIST_HEAD(&b->w.list);
200 b->next = NULL;
201 b->br_number = 4711;
202 b->n_req = 0;
203 b->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
204
205 mdev->oldest_tle = b;
206 mdev->newest_tle = b;
207 INIT_LIST_HEAD(&mdev->out_of_sequence_requests);
208
209 mdev->tl_hash = NULL;
210 mdev->tl_hash_s = 0;
211
212 return 1;
213}
214
215static void tl_cleanup(struct drbd_conf *mdev)
216{
217 D_ASSERT(mdev->oldest_tle == mdev->newest_tle);
218 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
219 kfree(mdev->oldest_tle);
220 mdev->oldest_tle = NULL;
221 kfree(mdev->unused_spare_tle);
222 mdev->unused_spare_tle = NULL;
223 kfree(mdev->tl_hash);
224 mdev->tl_hash = NULL;
225 mdev->tl_hash_s = 0;
226}
227
228/**
229 * _tl_add_barrier() - Adds a barrier to the transfer log
230 * @mdev: DRBD device.
231 * @new: Barrier to be added before the current head of the TL.
232 *
233 * The caller must hold the req_lock.
234 */
235void _tl_add_barrier(struct drbd_conf *mdev, struct drbd_tl_epoch *new)
236{
237 struct drbd_tl_epoch *newest_before;
238
239 INIT_LIST_HEAD(&new->requests);
240 INIT_LIST_HEAD(&new->w.list);
241 new->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
242 new->next = NULL;
243 new->n_req = 0;
244
245 newest_before = mdev->newest_tle;
246 /* never send a barrier number == 0, because that is special-cased
247 * when using TCQ for our write ordering code */
248 new->br_number = (newest_before->br_number+1) ?: 1;
249 if (mdev->newest_tle != new) {
250 mdev->newest_tle->next = new;
251 mdev->newest_tle = new;
252 }
253}
254
255/**
256 * tl_release() - Free or recycle the oldest &struct drbd_tl_epoch object of the TL
257 * @mdev: DRBD device.
258 * @barrier_nr: Expected identifier of the DRBD write barrier packet.
259 * @set_size: Expected number of requests before that barrier.
260 *
261 * In case the passed barrier_nr or set_size does not match the oldest
262 * &struct drbd_tl_epoch objects this function will cause a termination
263 * of the connection.
264 */
265void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
266 unsigned int set_size)
267{
268 struct drbd_tl_epoch *b, *nob; /* next old barrier */
269 struct list_head *le, *tle;
270 struct drbd_request *r;
271
272 spin_lock_irq(&mdev->req_lock);
273
274 b = mdev->oldest_tle;
275
276 /* first some paranoia code */
277 if (b == NULL) {
278 dev_err(DEV, "BAD! BarrierAck #%u received, but no epoch in tl!?\n",
279 barrier_nr);
280 goto bail;
281 }
282 if (b->br_number != barrier_nr) {
283 dev_err(DEV, "BAD! BarrierAck #%u received, expected #%u!\n",
284 barrier_nr, b->br_number);
285 goto bail;
286 }
287 if (b->n_req != set_size) {
288 dev_err(DEV, "BAD! BarrierAck #%u received with n_req=%u, expected n_req=%u!\n",
289 barrier_nr, set_size, b->n_req);
290 goto bail;
291 }
292
293 /* Clean up list of requests processed during current epoch */
294 list_for_each_safe(le, tle, &b->requests) {
295 r = list_entry(le, struct drbd_request, tl_requests);
296 _req_mod(r, barrier_acked);
297 }
298 /* There could be requests on the list waiting for completion
299 of the write to the local disk. To avoid corruptions of
300 slab's data structures we have to remove the lists head.
301
302 Also there could have been a barrier ack out of sequence, overtaking
303 the write acks - which would be a bug and violating write ordering.
304 To not deadlock in case we lose connection while such requests are
305 still pending, we need some way to find them for the
306 _req_mode(connection_lost_while_pending).
307
308 These have been list_move'd to the out_of_sequence_requests list in
309 _req_mod(, barrier_acked) above.
310 */
311 list_del_init(&b->requests);
312
313 nob = b->next;
314 if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags)) {
315 _tl_add_barrier(mdev, b);
316 if (nob)
317 mdev->oldest_tle = nob;
318 /* if nob == NULL b was the only barrier, and becomes the new
319 barrier. Therefore mdev->oldest_tle points already to b */
320 } else {
321 D_ASSERT(nob != NULL);
322 mdev->oldest_tle = nob;
323 kfree(b);
324 }
325
326 spin_unlock_irq(&mdev->req_lock);
327 dec_ap_pending(mdev);
328
329 return;
330
331bail:
332 spin_unlock_irq(&mdev->req_lock);
333 drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
334}
335
336
337/**
338 * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL
339 * @mdev: DRBD device.
340 *
341 * This is called after the connection to the peer was lost. The storage covered
342 * by the requests on the transfer gets marked as our of sync. Called from the
343 * receiver thread and the worker thread.
344 */
345void tl_clear(struct drbd_conf *mdev)
346{
347 struct drbd_tl_epoch *b, *tmp;
348 struct list_head *le, *tle;
349 struct drbd_request *r;
350 int new_initial_bnr = net_random();
351
352 spin_lock_irq(&mdev->req_lock);
353
354 b = mdev->oldest_tle;
355 while (b) {
356 list_for_each_safe(le, tle, &b->requests) {
357 r = list_entry(le, struct drbd_request, tl_requests);
358 /* It would be nice to complete outside of spinlock.
359 * But this is easier for now. */
360 _req_mod(r, connection_lost_while_pending);
361 }
362 tmp = b->next;
363
364 /* there could still be requests on that ring list,
365 * in case local io is still pending */
366 list_del(&b->requests);
367
368 /* dec_ap_pending corresponding to queue_barrier.
369 * the newest barrier may not have been queued yet,
370 * in which case w.cb is still NULL. */
371 if (b->w.cb != NULL)
372 dec_ap_pending(mdev);
373
374 if (b == mdev->newest_tle) {
375 /* recycle, but reinit! */
376 D_ASSERT(tmp == NULL);
377 INIT_LIST_HEAD(&b->requests);
378 INIT_LIST_HEAD(&b->w.list);
379 b->w.cb = NULL;
380 b->br_number = new_initial_bnr;
381 b->n_req = 0;
382
383 mdev->oldest_tle = b;
384 break;
385 }
386 kfree(b);
387 b = tmp;
388 }
389
390 /* we expect this list to be empty. */
391 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
392
393 /* but just in case, clean it up anyways! */
394 list_for_each_safe(le, tle, &mdev->out_of_sequence_requests) {
395 r = list_entry(le, struct drbd_request, tl_requests);
396 /* It would be nice to complete outside of spinlock.
397 * But this is easier for now. */
398 _req_mod(r, connection_lost_while_pending);
399 }
400
401 /* ensure bit indicating barrier is required is clear */
402 clear_bit(CREATE_BARRIER, &mdev->flags);
403
404 spin_unlock_irq(&mdev->req_lock);
405}
406
407/**
408 * cl_wide_st_chg() - TRUE if the state change is a cluster wide one
409 * @mdev: DRBD device.
410 * @os: old (current) state.
411 * @ns: new (wanted) state.
412 */
413static int cl_wide_st_chg(struct drbd_conf *mdev,
414 union drbd_state os, union drbd_state ns)
415{
416 return (os.conn >= C_CONNECTED && ns.conn >= C_CONNECTED &&
417 ((os.role != R_PRIMARY && ns.role == R_PRIMARY) ||
418 (os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
419 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S) ||
420 (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))) ||
421 (os.conn >= C_CONNECTED && ns.conn == C_DISCONNECTING) ||
422 (os.conn == C_CONNECTED && ns.conn == C_VERIFY_S);
423}
424
425int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f,
426 union drbd_state mask, union drbd_state val)
427{
428 unsigned long flags;
429 union drbd_state os, ns;
430 int rv;
431
432 spin_lock_irqsave(&mdev->req_lock, flags);
433 os = mdev->state;
434 ns.i = (os.i & ~mask.i) | val.i;
435 rv = _drbd_set_state(mdev, ns, f, NULL);
436 ns = mdev->state;
437 spin_unlock_irqrestore(&mdev->req_lock, flags);
438
439 return rv;
440}
441
442/**
443 * drbd_force_state() - Impose a change which happens outside our control on our state
444 * @mdev: DRBD device.
445 * @mask: mask of state bits to change.
446 * @val: value of new state bits.
447 */
448void drbd_force_state(struct drbd_conf *mdev,
449 union drbd_state mask, union drbd_state val)
450{
451 drbd_change_state(mdev, CS_HARD, mask, val);
452}
453
454static int is_valid_state(struct drbd_conf *mdev, union drbd_state ns);
455static int is_valid_state_transition(struct drbd_conf *,
456 union drbd_state, union drbd_state);
457static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
458 union drbd_state ns, int *warn_sync_abort);
459int drbd_send_state_req(struct drbd_conf *,
460 union drbd_state, union drbd_state);
461
462static enum drbd_state_ret_codes _req_st_cond(struct drbd_conf *mdev,
463 union drbd_state mask, union drbd_state val)
464{
465 union drbd_state os, ns;
466 unsigned long flags;
467 int rv;
468
469 if (test_and_clear_bit(CL_ST_CHG_SUCCESS, &mdev->flags))
470 return SS_CW_SUCCESS;
471
472 if (test_and_clear_bit(CL_ST_CHG_FAIL, &mdev->flags))
473 return SS_CW_FAILED_BY_PEER;
474
475 rv = 0;
476 spin_lock_irqsave(&mdev->req_lock, flags);
477 os = mdev->state;
478 ns.i = (os.i & ~mask.i) | val.i;
479 ns = sanitize_state(mdev, os, ns, NULL);
480
481 if (!cl_wide_st_chg(mdev, os, ns))
482 rv = SS_CW_NO_NEED;
483 if (!rv) {
484 rv = is_valid_state(mdev, ns);
485 if (rv == SS_SUCCESS) {
486 rv = is_valid_state_transition(mdev, ns, os);
487 if (rv == SS_SUCCESS)
488 rv = 0; /* cont waiting, otherwise fail. */
489 }
490 }
491 spin_unlock_irqrestore(&mdev->req_lock, flags);
492
493 return rv;
494}
495
496/**
497 * drbd_req_state() - Perform an eventually cluster wide state change
498 * @mdev: DRBD device.
499 * @mask: mask of state bits to change.
500 * @val: value of new state bits.
501 * @f: flags
502 *
503 * Should not be called directly, use drbd_request_state() or
504 * _drbd_request_state().
505 */
506static int drbd_req_state(struct drbd_conf *mdev,
507 union drbd_state mask, union drbd_state val,
508 enum chg_state_flags f)
509{
510 struct completion done;
511 unsigned long flags;
512 union drbd_state os, ns;
513 int rv;
514
515 init_completion(&done);
516
517 if (f & CS_SERIALIZE)
518 mutex_lock(&mdev->state_mutex);
519
520 spin_lock_irqsave(&mdev->req_lock, flags);
521 os = mdev->state;
522 ns.i = (os.i & ~mask.i) | val.i;
523 ns = sanitize_state(mdev, os, ns, NULL);
524
525 if (cl_wide_st_chg(mdev, os, ns)) {
526 rv = is_valid_state(mdev, ns);
527 if (rv == SS_SUCCESS)
528 rv = is_valid_state_transition(mdev, ns, os);
529 spin_unlock_irqrestore(&mdev->req_lock, flags);
530
531 if (rv < SS_SUCCESS) {
532 if (f & CS_VERBOSE)
533 print_st_err(mdev, os, ns, rv);
534 goto abort;
535 }
536
537 drbd_state_lock(mdev);
538 if (!drbd_send_state_req(mdev, mask, val)) {
539 drbd_state_unlock(mdev);
540 rv = SS_CW_FAILED_BY_PEER;
541 if (f & CS_VERBOSE)
542 print_st_err(mdev, os, ns, rv);
543 goto abort;
544 }
545
546 wait_event(mdev->state_wait,
547 (rv = _req_st_cond(mdev, mask, val)));
548
549 if (rv < SS_SUCCESS) {
550 drbd_state_unlock(mdev);
551 if (f & CS_VERBOSE)
552 print_st_err(mdev, os, ns, rv);
553 goto abort;
554 }
555 spin_lock_irqsave(&mdev->req_lock, flags);
556 os = mdev->state;
557 ns.i = (os.i & ~mask.i) | val.i;
558 rv = _drbd_set_state(mdev, ns, f, &done);
559 drbd_state_unlock(mdev);
560 } else {
561 rv = _drbd_set_state(mdev, ns, f, &done);
562 }
563
564 spin_unlock_irqrestore(&mdev->req_lock, flags);
565
566 if (f & CS_WAIT_COMPLETE && rv == SS_SUCCESS) {
567 D_ASSERT(current != mdev->worker.task);
568 wait_for_completion(&done);
569 }
570
571abort:
572 if (f & CS_SERIALIZE)
573 mutex_unlock(&mdev->state_mutex);
574
575 return rv;
576}
577
578/**
579 * _drbd_request_state() - Request a state change (with flags)
580 * @mdev: DRBD device.
581 * @mask: mask of state bits to change.
582 * @val: value of new state bits.
583 * @f: flags
584 *
585 * Cousin of drbd_request_state(), useful with the CS_WAIT_COMPLETE
586 * flag, or when logging of failed state change requests is not desired.
587 */
588int _drbd_request_state(struct drbd_conf *mdev, union drbd_state mask,
589 union drbd_state val, enum chg_state_flags f)
590{
591 int rv;
592
593 wait_event(mdev->state_wait,
594 (rv = drbd_req_state(mdev, mask, val, f)) != SS_IN_TRANSIENT_STATE);
595
596 return rv;
597}
598
599static void print_st(struct drbd_conf *mdev, char *name, union drbd_state ns)
600{
601 dev_err(DEV, " %s = { cs:%s ro:%s/%s ds:%s/%s %c%c%c%c }\n",
602 name,
603 drbd_conn_str(ns.conn),
604 drbd_role_str(ns.role),
605 drbd_role_str(ns.peer),
606 drbd_disk_str(ns.disk),
607 drbd_disk_str(ns.pdsk),
608 ns.susp ? 's' : 'r',
609 ns.aftr_isp ? 'a' : '-',
610 ns.peer_isp ? 'p' : '-',
611 ns.user_isp ? 'u' : '-'
612 );
613}
614
615void print_st_err(struct drbd_conf *mdev,
616 union drbd_state os, union drbd_state ns, int err)
617{
618 if (err == SS_IN_TRANSIENT_STATE)
619 return;
620 dev_err(DEV, "State change failed: %s\n", drbd_set_st_err_str(err));
621 print_st(mdev, " state", os);
622 print_st(mdev, "wanted", ns);
623}
624
625
626#define drbd_peer_str drbd_role_str
627#define drbd_pdsk_str drbd_disk_str
628
629#define drbd_susp_str(A) ((A) ? "1" : "0")
630#define drbd_aftr_isp_str(A) ((A) ? "1" : "0")
631#define drbd_peer_isp_str(A) ((A) ? "1" : "0")
632#define drbd_user_isp_str(A) ((A) ? "1" : "0")
633
634#define PSC(A) \
635 ({ if (ns.A != os.A) { \
636 pbp += sprintf(pbp, #A "( %s -> %s ) ", \
637 drbd_##A##_str(os.A), \
638 drbd_##A##_str(ns.A)); \
639 } })
640
641/**
642 * is_valid_state() - Returns an SS_ error code if ns is not valid
643 * @mdev: DRBD device.
644 * @ns: State to consider.
645 */
646static int is_valid_state(struct drbd_conf *mdev, union drbd_state ns)
647{
648 /* See drbd_state_sw_errors in drbd_strings.c */
649
650 enum drbd_fencing_p fp;
651 int rv = SS_SUCCESS;
652
653 fp = FP_DONT_CARE;
654 if (get_ldev(mdev)) {
655 fp = mdev->ldev->dc.fencing;
656 put_ldev(mdev);
657 }
658
659 if (get_net_conf(mdev)) {
660 if (!mdev->net_conf->two_primaries &&
661 ns.role == R_PRIMARY && ns.peer == R_PRIMARY)
662 rv = SS_TWO_PRIMARIES;
663 put_net_conf(mdev);
664 }
665
666 if (rv <= 0)
667 /* already found a reason to abort */;
668 else if (ns.role == R_SECONDARY && mdev->open_cnt)
669 rv = SS_DEVICE_IN_USE;
670
671 else if (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.disk < D_UP_TO_DATE)
672 rv = SS_NO_UP_TO_DATE_DISK;
673
674 else if (fp >= FP_RESOURCE &&
675 ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk >= D_UNKNOWN)
676 rv = SS_PRIMARY_NOP;
677
678 else if (ns.role == R_PRIMARY && ns.disk <= D_INCONSISTENT && ns.pdsk <= D_INCONSISTENT)
679 rv = SS_NO_UP_TO_DATE_DISK;
680
681 else if (ns.conn > C_CONNECTED && ns.disk < D_INCONSISTENT)
682 rv = SS_NO_LOCAL_DISK;
683
684 else if (ns.conn > C_CONNECTED && ns.pdsk < D_INCONSISTENT)
685 rv = SS_NO_REMOTE_DISK;
686
687 else if ((ns.conn == C_CONNECTED ||
688 ns.conn == C_WF_BITMAP_S ||
689 ns.conn == C_SYNC_SOURCE ||
690 ns.conn == C_PAUSED_SYNC_S) &&
691 ns.disk == D_OUTDATED)
692 rv = SS_CONNECTED_OUTDATES;
693
694 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
695 (mdev->sync_conf.verify_alg[0] == 0))
696 rv = SS_NO_VERIFY_ALG;
697
698 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
699 mdev->agreed_pro_version < 88)
700 rv = SS_NOT_SUPPORTED;
701
702 return rv;
703}
704
705/**
706 * is_valid_state_transition() - Returns an SS_ error code if the state transition is not possible
707 * @mdev: DRBD device.
708 * @ns: new state.
709 * @os: old state.
710 */
711static int is_valid_state_transition(struct drbd_conf *mdev,
712 union drbd_state ns, union drbd_state os)
713{
714 int rv = SS_SUCCESS;
715
716 if ((ns.conn == C_STARTING_SYNC_T || ns.conn == C_STARTING_SYNC_S) &&
717 os.conn > C_CONNECTED)
718 rv = SS_RESYNC_RUNNING;
719
720 if (ns.conn == C_DISCONNECTING && os.conn == C_STANDALONE)
721 rv = SS_ALREADY_STANDALONE;
722
723 if (ns.disk > D_ATTACHING && os.disk == D_DISKLESS)
724 rv = SS_IS_DISKLESS;
725
726 if (ns.conn == C_WF_CONNECTION && os.conn < C_UNCONNECTED)
727 rv = SS_NO_NET_CONFIG;
728
729 if (ns.disk == D_OUTDATED && os.disk < D_OUTDATED && os.disk != D_ATTACHING)
730 rv = SS_LOWER_THAN_OUTDATED;
731
732 if (ns.conn == C_DISCONNECTING && os.conn == C_UNCONNECTED)
733 rv = SS_IN_TRANSIENT_STATE;
734
735 if (ns.conn == os.conn && ns.conn == C_WF_REPORT_PARAMS)
736 rv = SS_IN_TRANSIENT_STATE;
737
738 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && os.conn < C_CONNECTED)
739 rv = SS_NEED_CONNECTION;
740
741 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
742 ns.conn != os.conn && os.conn > C_CONNECTED)
743 rv = SS_RESYNC_RUNNING;
744
745 if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) &&
746 os.conn < C_CONNECTED)
747 rv = SS_NEED_CONNECTION;
748
749 return rv;
750}
751
752/**
753 * sanitize_state() - Resolves implicitly necessary additional changes to a state transition
754 * @mdev: DRBD device.
755 * @os: old state.
756 * @ns: new state.
757 * @warn_sync_abort:
758 *
759 * When we loose connection, we have to set the state of the peers disk (pdsk)
760 * to D_UNKNOWN. This rule and many more along those lines are in this function.
761 */
762static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
763 union drbd_state ns, int *warn_sync_abort)
764{
765 enum drbd_fencing_p fp;
766
767 fp = FP_DONT_CARE;
768 if (get_ldev(mdev)) {
769 fp = mdev->ldev->dc.fencing;
770 put_ldev(mdev);
771 }
772
773 /* Disallow Network errors to configure a device's network part */
774 if ((ns.conn >= C_TIMEOUT && ns.conn <= C_TEAR_DOWN) &&
775 os.conn <= C_DISCONNECTING)
776 ns.conn = os.conn;
777
778 /* After a network error (+C_TEAR_DOWN) only C_UNCONNECTED or C_DISCONNECTING can follow */
779 if (os.conn >= C_TIMEOUT && os.conn <= C_TEAR_DOWN &&
780 ns.conn != C_UNCONNECTED && ns.conn != C_DISCONNECTING)
781 ns.conn = os.conn;
782
783 /* After C_DISCONNECTING only C_STANDALONE may follow */
784 if (os.conn == C_DISCONNECTING && ns.conn != C_STANDALONE)
785 ns.conn = os.conn;
786
787 if (ns.conn < C_CONNECTED) {
788 ns.peer_isp = 0;
789 ns.peer = R_UNKNOWN;
790 if (ns.pdsk > D_UNKNOWN || ns.pdsk < D_INCONSISTENT)
791 ns.pdsk = D_UNKNOWN;
792 }
793
794 /* Clear the aftr_isp when becoming unconfigured */
795 if (ns.conn == C_STANDALONE && ns.disk == D_DISKLESS && ns.role == R_SECONDARY)
796 ns.aftr_isp = 0;
797
798 if (ns.conn <= C_DISCONNECTING && ns.disk == D_DISKLESS)
799 ns.pdsk = D_UNKNOWN;
800
801 /* Abort resync if a disk fails/detaches */
802 if (os.conn > C_CONNECTED && ns.conn > C_CONNECTED &&
803 (ns.disk <= D_FAILED || ns.pdsk <= D_FAILED)) {
804 if (warn_sync_abort)
805 *warn_sync_abort = 1;
806 ns.conn = C_CONNECTED;
807 }
808
809 if (ns.conn >= C_CONNECTED &&
810 ((ns.disk == D_CONSISTENT || ns.disk == D_OUTDATED) ||
811 (ns.disk == D_NEGOTIATING && ns.conn == C_WF_BITMAP_T))) {
812 switch (ns.conn) {
813 case C_WF_BITMAP_T:
814 case C_PAUSED_SYNC_T:
815 ns.disk = D_OUTDATED;
816 break;
817 case C_CONNECTED:
818 case C_WF_BITMAP_S:
819 case C_SYNC_SOURCE:
820 case C_PAUSED_SYNC_S:
821 ns.disk = D_UP_TO_DATE;
822 break;
823 case C_SYNC_TARGET:
824 ns.disk = D_INCONSISTENT;
825 dev_warn(DEV, "Implicitly set disk state Inconsistent!\n");
826 break;
827 }
828 if (os.disk == D_OUTDATED && ns.disk == D_UP_TO_DATE)
829 dev_warn(DEV, "Implicitly set disk from Outdated to UpToDate\n");
830 }
831
832 if (ns.conn >= C_CONNECTED &&
833 (ns.pdsk == D_CONSISTENT || ns.pdsk == D_OUTDATED)) {
834 switch (ns.conn) {
835 case C_CONNECTED:
836 case C_WF_BITMAP_T:
837 case C_PAUSED_SYNC_T:
838 case C_SYNC_TARGET:
839 ns.pdsk = D_UP_TO_DATE;
840 break;
841 case C_WF_BITMAP_S:
842 case C_PAUSED_SYNC_S:
843 ns.pdsk = D_OUTDATED;
844 break;
845 case C_SYNC_SOURCE:
846 ns.pdsk = D_INCONSISTENT;
847 dev_warn(DEV, "Implicitly set pdsk Inconsistent!\n");
848 break;
849 }
850 if (os.pdsk == D_OUTDATED && ns.pdsk == D_UP_TO_DATE)
851 dev_warn(DEV, "Implicitly set pdsk from Outdated to UpToDate\n");
852 }
853
854 /* Connection breaks down before we finished "Negotiating" */
855 if (ns.conn < C_CONNECTED && ns.disk == D_NEGOTIATING &&
856 get_ldev_if_state(mdev, D_NEGOTIATING)) {
857 if (mdev->ed_uuid == mdev->ldev->md.uuid[UI_CURRENT]) {
858 ns.disk = mdev->new_state_tmp.disk;
859 ns.pdsk = mdev->new_state_tmp.pdsk;
860 } else {
861 dev_alert(DEV, "Connection lost while negotiating, no data!\n");
862 ns.disk = D_DISKLESS;
863 ns.pdsk = D_UNKNOWN;
864 }
865 put_ldev(mdev);
866 }
867
868 if (fp == FP_STONITH &&
Philipp Reisner0a492162009-10-21 13:08:29 +0200869 (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk > D_OUTDATED) &&
870 !(os.role == R_PRIMARY && os.conn < C_CONNECTED && os.pdsk > D_OUTDATED))
871 ns.susp = 1;
Philipp Reisnerb411b362009-09-25 16:07:19 -0700872
873 if (ns.aftr_isp || ns.peer_isp || ns.user_isp) {
874 if (ns.conn == C_SYNC_SOURCE)
875 ns.conn = C_PAUSED_SYNC_S;
876 if (ns.conn == C_SYNC_TARGET)
877 ns.conn = C_PAUSED_SYNC_T;
878 } else {
879 if (ns.conn == C_PAUSED_SYNC_S)
880 ns.conn = C_SYNC_SOURCE;
881 if (ns.conn == C_PAUSED_SYNC_T)
882 ns.conn = C_SYNC_TARGET;
883 }
884
885 return ns;
886}
887
888/* helper for __drbd_set_state */
889static void set_ov_position(struct drbd_conf *mdev, enum drbd_conns cs)
890{
891 if (cs == C_VERIFY_T) {
892 /* starting online verify from an arbitrary position
893 * does not fit well into the existing protocol.
894 * on C_VERIFY_T, we initialize ov_left and friends
895 * implicitly in receive_DataRequest once the
896 * first P_OV_REQUEST is received */
897 mdev->ov_start_sector = ~(sector_t)0;
898 } else {
899 unsigned long bit = BM_SECT_TO_BIT(mdev->ov_start_sector);
900 if (bit >= mdev->rs_total)
901 mdev->ov_start_sector =
902 BM_BIT_TO_SECT(mdev->rs_total - 1);
903 mdev->ov_position = mdev->ov_start_sector;
904 }
905}
906
907/**
908 * __drbd_set_state() - Set a new DRBD state
909 * @mdev: DRBD device.
910 * @ns: new state.
911 * @flags: Flags
912 * @done: Optional completion, that will get completed after the after_state_ch() finished
913 *
914 * Caller needs to hold req_lock, and global_state_lock. Do not call directly.
915 */
916int __drbd_set_state(struct drbd_conf *mdev,
917 union drbd_state ns, enum chg_state_flags flags,
918 struct completion *done)
919{
920 union drbd_state os;
921 int rv = SS_SUCCESS;
922 int warn_sync_abort = 0;
923 struct after_state_chg_work *ascw;
924
925 os = mdev->state;
926
927 ns = sanitize_state(mdev, os, ns, &warn_sync_abort);
928
929 if (ns.i == os.i)
930 return SS_NOTHING_TO_DO;
931
932 if (!(flags & CS_HARD)) {
933 /* pre-state-change checks ; only look at ns */
934 /* See drbd_state_sw_errors in drbd_strings.c */
935
936 rv = is_valid_state(mdev, ns);
937 if (rv < SS_SUCCESS) {
938 /* If the old state was illegal as well, then let
939 this happen...*/
940
941 if (is_valid_state(mdev, os) == rv) {
942 dev_err(DEV, "Considering state change from bad state. "
943 "Error would be: '%s'\n",
944 drbd_set_st_err_str(rv));
945 print_st(mdev, "old", os);
946 print_st(mdev, "new", ns);
947 rv = is_valid_state_transition(mdev, ns, os);
948 }
949 } else
950 rv = is_valid_state_transition(mdev, ns, os);
951 }
952
953 if (rv < SS_SUCCESS) {
954 if (flags & CS_VERBOSE)
955 print_st_err(mdev, os, ns, rv);
956 return rv;
957 }
958
959 if (warn_sync_abort)
960 dev_warn(DEV, "Resync aborted.\n");
961
962 {
963 char *pbp, pb[300];
964 pbp = pb;
965 *pbp = 0;
966 PSC(role);
967 PSC(peer);
968 PSC(conn);
969 PSC(disk);
970 PSC(pdsk);
971 PSC(susp);
972 PSC(aftr_isp);
973 PSC(peer_isp);
974 PSC(user_isp);
975 dev_info(DEV, "%s\n", pb);
976 }
977
978 /* solve the race between becoming unconfigured,
979 * worker doing the cleanup, and
980 * admin reconfiguring us:
981 * on (re)configure, first set CONFIG_PENDING,
982 * then wait for a potentially exiting worker,
983 * start the worker, and schedule one no_op.
984 * then proceed with configuration.
985 */
986 if (ns.disk == D_DISKLESS &&
987 ns.conn == C_STANDALONE &&
988 ns.role == R_SECONDARY &&
989 !test_and_set_bit(CONFIG_PENDING, &mdev->flags))
990 set_bit(DEVICE_DYING, &mdev->flags);
991
992 mdev->state.i = ns.i;
993 wake_up(&mdev->misc_wait);
994 wake_up(&mdev->state_wait);
995
996 /* post-state-change actions */
997 if (os.conn >= C_SYNC_SOURCE && ns.conn <= C_CONNECTED) {
998 set_bit(STOP_SYNC_TIMER, &mdev->flags);
999 mod_timer(&mdev->resync_timer, jiffies);
1000 }
1001
1002 /* aborted verify run. log the last position */
1003 if ((os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) &&
1004 ns.conn < C_CONNECTED) {
1005 mdev->ov_start_sector =
1006 BM_BIT_TO_SECT(mdev->rs_total - mdev->ov_left);
1007 dev_info(DEV, "Online Verify reached sector %llu\n",
1008 (unsigned long long)mdev->ov_start_sector);
1009 }
1010
1011 if ((os.conn == C_PAUSED_SYNC_T || os.conn == C_PAUSED_SYNC_S) &&
1012 (ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)) {
1013 dev_info(DEV, "Syncer continues.\n");
1014 mdev->rs_paused += (long)jiffies-(long)mdev->rs_mark_time;
1015 if (ns.conn == C_SYNC_TARGET) {
1016 if (!test_and_clear_bit(STOP_SYNC_TIMER, &mdev->flags))
1017 mod_timer(&mdev->resync_timer, jiffies);
1018 /* This if (!test_bit) is only needed for the case
1019 that a device that has ceased to used its timer,
1020 i.e. it is already in drbd_resync_finished() gets
1021 paused and resumed. */
1022 }
1023 }
1024
1025 if ((os.conn == C_SYNC_TARGET || os.conn == C_SYNC_SOURCE) &&
1026 (ns.conn == C_PAUSED_SYNC_T || ns.conn == C_PAUSED_SYNC_S)) {
1027 dev_info(DEV, "Resync suspended\n");
1028 mdev->rs_mark_time = jiffies;
1029 if (ns.conn == C_PAUSED_SYNC_T)
1030 set_bit(STOP_SYNC_TIMER, &mdev->flags);
1031 }
1032
1033 if (os.conn == C_CONNECTED &&
1034 (ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T)) {
1035 mdev->ov_position = 0;
1036 mdev->rs_total =
1037 mdev->rs_mark_left = drbd_bm_bits(mdev);
1038 if (mdev->agreed_pro_version >= 90)
1039 set_ov_position(mdev, ns.conn);
1040 else
1041 mdev->ov_start_sector = 0;
1042 mdev->ov_left = mdev->rs_total
1043 - BM_SECT_TO_BIT(mdev->ov_position);
1044 mdev->rs_start =
1045 mdev->rs_mark_time = jiffies;
1046 mdev->ov_last_oos_size = 0;
1047 mdev->ov_last_oos_start = 0;
1048
1049 if (ns.conn == C_VERIFY_S) {
1050 dev_info(DEV, "Starting Online Verify from sector %llu\n",
1051 (unsigned long long)mdev->ov_position);
1052 mod_timer(&mdev->resync_timer, jiffies);
1053 }
1054 }
1055
1056 if (get_ldev(mdev)) {
1057 u32 mdf = mdev->ldev->md.flags & ~(MDF_CONSISTENT|MDF_PRIMARY_IND|
1058 MDF_CONNECTED_IND|MDF_WAS_UP_TO_DATE|
1059 MDF_PEER_OUT_DATED|MDF_CRASHED_PRIMARY);
1060
1061 if (test_bit(CRASHED_PRIMARY, &mdev->flags))
1062 mdf |= MDF_CRASHED_PRIMARY;
1063 if (mdev->state.role == R_PRIMARY ||
1064 (mdev->state.pdsk < D_INCONSISTENT && mdev->state.peer == R_PRIMARY))
1065 mdf |= MDF_PRIMARY_IND;
1066 if (mdev->state.conn > C_WF_REPORT_PARAMS)
1067 mdf |= MDF_CONNECTED_IND;
1068 if (mdev->state.disk > D_INCONSISTENT)
1069 mdf |= MDF_CONSISTENT;
1070 if (mdev->state.disk > D_OUTDATED)
1071 mdf |= MDF_WAS_UP_TO_DATE;
1072 if (mdev->state.pdsk <= D_OUTDATED && mdev->state.pdsk >= D_INCONSISTENT)
1073 mdf |= MDF_PEER_OUT_DATED;
1074 if (mdf != mdev->ldev->md.flags) {
1075 mdev->ldev->md.flags = mdf;
1076 drbd_md_mark_dirty(mdev);
1077 }
1078 if (os.disk < D_CONSISTENT && ns.disk >= D_CONSISTENT)
1079 drbd_set_ed_uuid(mdev, mdev->ldev->md.uuid[UI_CURRENT]);
1080 put_ldev(mdev);
1081 }
1082
1083 /* Peer was forced D_UP_TO_DATE & R_PRIMARY, consider to resync */
1084 if (os.disk == D_INCONSISTENT && os.pdsk == D_INCONSISTENT &&
1085 os.peer == R_SECONDARY && ns.peer == R_PRIMARY)
1086 set_bit(CONSIDER_RESYNC, &mdev->flags);
1087
1088 /* Receiver should clean up itself */
1089 if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING)
1090 drbd_thread_stop_nowait(&mdev->receiver);
1091
1092 /* Now the receiver finished cleaning up itself, it should die */
1093 if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE)
1094 drbd_thread_stop_nowait(&mdev->receiver);
1095
1096 /* Upon network failure, we need to restart the receiver. */
1097 if (os.conn > C_TEAR_DOWN &&
1098 ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT)
1099 drbd_thread_restart_nowait(&mdev->receiver);
1100
1101 ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC);
1102 if (ascw) {
1103 ascw->os = os;
1104 ascw->ns = ns;
1105 ascw->flags = flags;
1106 ascw->w.cb = w_after_state_ch;
1107 ascw->done = done;
1108 drbd_queue_work(&mdev->data.work, &ascw->w);
1109 } else {
1110 dev_warn(DEV, "Could not kmalloc an ascw\n");
1111 }
1112
1113 return rv;
1114}
1115
1116static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused)
1117{
1118 struct after_state_chg_work *ascw =
1119 container_of(w, struct after_state_chg_work, w);
1120 after_state_ch(mdev, ascw->os, ascw->ns, ascw->flags);
1121 if (ascw->flags & CS_WAIT_COMPLETE) {
1122 D_ASSERT(ascw->done != NULL);
1123 complete(ascw->done);
1124 }
1125 kfree(ascw);
1126
1127 return 1;
1128}
1129
1130static void abw_start_sync(struct drbd_conf *mdev, int rv)
1131{
1132 if (rv) {
1133 dev_err(DEV, "Writing the bitmap failed not starting resync.\n");
1134 _drbd_request_state(mdev, NS(conn, C_CONNECTED), CS_VERBOSE);
1135 return;
1136 }
1137
1138 switch (mdev->state.conn) {
1139 case C_STARTING_SYNC_T:
1140 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE);
1141 break;
1142 case C_STARTING_SYNC_S:
1143 drbd_start_resync(mdev, C_SYNC_SOURCE);
1144 break;
1145 }
1146}
1147
1148/**
1149 * after_state_ch() - Perform after state change actions that may sleep
1150 * @mdev: DRBD device.
1151 * @os: old state.
1152 * @ns: new state.
1153 * @flags: Flags
1154 */
1155static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
1156 union drbd_state ns, enum chg_state_flags flags)
1157{
1158 enum drbd_fencing_p fp;
1159
1160 if (os.conn != C_CONNECTED && ns.conn == C_CONNECTED) {
1161 clear_bit(CRASHED_PRIMARY, &mdev->flags);
1162 if (mdev->p_uuid)
1163 mdev->p_uuid[UI_FLAGS] &= ~((u64)2);
1164 }
1165
1166 fp = FP_DONT_CARE;
1167 if (get_ldev(mdev)) {
1168 fp = mdev->ldev->dc.fencing;
1169 put_ldev(mdev);
1170 }
1171
1172 /* Inform userspace about the change... */
1173 drbd_bcast_state(mdev, ns);
1174
1175 if (!(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE) &&
1176 (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE))
1177 drbd_khelper(mdev, "pri-on-incon-degr");
1178
1179 /* Here we have the actions that are performed after a
1180 state change. This function might sleep */
1181
1182 if (fp == FP_STONITH && ns.susp) {
1183 /* case1: The outdate peer handler is successful:
1184 * case2: The connection was established again: */
1185 if ((os.pdsk > D_OUTDATED && ns.pdsk <= D_OUTDATED) ||
1186 (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)) {
1187 tl_clear(mdev);
1188 spin_lock_irq(&mdev->req_lock);
1189 _drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL);
1190 spin_unlock_irq(&mdev->req_lock);
1191 }
1192 }
1193 /* Do not change the order of the if above and the two below... */
1194 if (os.pdsk == D_DISKLESS && ns.pdsk > D_DISKLESS) { /* attach on the peer */
1195 drbd_send_uuids(mdev);
1196 drbd_send_state(mdev);
1197 }
1198 if (os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S)
1199 drbd_queue_bitmap_io(mdev, &drbd_send_bitmap, NULL, "send_bitmap (WFBitMapS)");
1200
1201 /* Lost contact to peer's copy of the data */
1202 if ((os.pdsk >= D_INCONSISTENT &&
1203 os.pdsk != D_UNKNOWN &&
1204 os.pdsk != D_OUTDATED)
1205 && (ns.pdsk < D_INCONSISTENT ||
1206 ns.pdsk == D_UNKNOWN ||
1207 ns.pdsk == D_OUTDATED)) {
1208 kfree(mdev->p_uuid);
1209 mdev->p_uuid = NULL;
1210 if (get_ldev(mdev)) {
1211 if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) &&
1212 mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) {
1213 drbd_uuid_new_current(mdev);
1214 drbd_send_uuids(mdev);
1215 }
1216 put_ldev(mdev);
1217 }
1218 }
1219
1220 if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) {
1221 if (ns.peer == R_PRIMARY && mdev->ldev->md.uuid[UI_BITMAP] == 0)
1222 drbd_uuid_new_current(mdev);
1223
1224 /* D_DISKLESS Peer becomes secondary */
1225 if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
1226 drbd_al_to_on_disk_bm(mdev);
1227 put_ldev(mdev);
1228 }
1229
1230 /* Last part of the attaching process ... */
1231 if (ns.conn >= C_CONNECTED &&
1232 os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
1233 kfree(mdev->p_uuid); /* We expect to receive up-to-date UUIDs soon. */
1234 mdev->p_uuid = NULL; /* ...to not use the old ones in the mean time */
1235 drbd_send_sizes(mdev, 0); /* to start sync... */
1236 drbd_send_uuids(mdev);
1237 drbd_send_state(mdev);
1238 }
1239
1240 /* We want to pause/continue resync, tell peer. */
1241 if (ns.conn >= C_CONNECTED &&
1242 ((os.aftr_isp != ns.aftr_isp) ||
1243 (os.user_isp != ns.user_isp)))
1244 drbd_send_state(mdev);
1245
1246 /* In case one of the isp bits got set, suspend other devices. */
1247 if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
1248 (ns.aftr_isp || ns.peer_isp || ns.user_isp))
1249 suspend_other_sg(mdev);
1250
1251 /* Make sure the peer gets informed about eventual state
1252 changes (ISP bits) while we were in WFReportParams. */
1253 if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
1254 drbd_send_state(mdev);
1255
1256 /* We are in the progress to start a full sync... */
1257 if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
1258 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S))
1259 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, &abw_start_sync, "set_n_write from StartingSync");
1260
1261 /* We are invalidating our self... */
1262 if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED &&
1263 os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT)
1264 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL, "set_n_write from invalidate");
1265
1266 if (os.disk > D_FAILED && ns.disk == D_FAILED) {
1267 enum drbd_io_error_p eh;
1268
1269 eh = EP_PASS_ON;
1270 if (get_ldev_if_state(mdev, D_FAILED)) {
1271 eh = mdev->ldev->dc.on_io_error;
1272 put_ldev(mdev);
1273 }
1274
1275 drbd_rs_cancel_all(mdev);
1276 /* since get_ldev() only works as long as disk>=D_INCONSISTENT,
1277 and it is D_DISKLESS here, local_cnt can only go down, it can
1278 not increase... It will reach zero */
1279 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1280 mdev->rs_total = 0;
1281 mdev->rs_failed = 0;
1282 atomic_set(&mdev->rs_pending_cnt, 0);
1283
1284 spin_lock_irq(&mdev->req_lock);
1285 _drbd_set_state(_NS(mdev, disk, D_DISKLESS), CS_HARD, NULL);
1286 spin_unlock_irq(&mdev->req_lock);
1287
1288 if (eh == EP_CALL_HELPER)
1289 drbd_khelper(mdev, "local-io-error");
1290 }
1291
1292 if (os.disk > D_DISKLESS && ns.disk == D_DISKLESS) {
1293
1294 if (os.disk == D_FAILED) /* && ns.disk == D_DISKLESS*/ {
1295 if (drbd_send_state(mdev))
1296 dev_warn(DEV, "Notified peer that my disk is broken.\n");
1297 else
1298 dev_err(DEV, "Sending state in drbd_io_error() failed\n");
1299 }
1300
Philipp Reisner0a6dbf22009-12-28 16:58:38 +01001301 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
Philipp Reisnerb411b362009-09-25 16:07:19 -07001302 lc_destroy(mdev->resync);
1303 mdev->resync = NULL;
1304 lc_destroy(mdev->act_log);
1305 mdev->act_log = NULL;
1306 __no_warn(local,
1307 drbd_free_bc(mdev->ldev);
1308 mdev->ldev = NULL;);
1309
1310 if (mdev->md_io_tmpp)
1311 __free_page(mdev->md_io_tmpp);
1312 }
1313
1314 /* Disks got bigger while they were detached */
1315 if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
1316 test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) {
1317 if (ns.conn == C_CONNECTED)
1318 resync_after_online_grow(mdev);
1319 }
1320
1321 /* A resync finished or aborted, wake paused devices... */
1322 if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) ||
1323 (os.peer_isp && !ns.peer_isp) ||
1324 (os.user_isp && !ns.user_isp))
1325 resume_next_sg(mdev);
1326
1327 /* Upon network connection, we need to start the receiver */
1328 if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED)
1329 drbd_thread_start(&mdev->receiver);
1330
1331 /* Terminate worker thread if we are unconfigured - it will be
1332 restarted as needed... */
1333 if (ns.disk == D_DISKLESS &&
1334 ns.conn == C_STANDALONE &&
1335 ns.role == R_SECONDARY) {
1336 if (os.aftr_isp != ns.aftr_isp)
1337 resume_next_sg(mdev);
1338 /* set in __drbd_set_state, unless CONFIG_PENDING was set */
1339 if (test_bit(DEVICE_DYING, &mdev->flags))
1340 drbd_thread_stop_nowait(&mdev->worker);
1341 }
1342
1343 drbd_md_sync(mdev);
1344}
1345
1346
1347static int drbd_thread_setup(void *arg)
1348{
1349 struct drbd_thread *thi = (struct drbd_thread *) arg;
1350 struct drbd_conf *mdev = thi->mdev;
1351 unsigned long flags;
1352 int retval;
1353
1354restart:
1355 retval = thi->function(thi);
1356
1357 spin_lock_irqsave(&thi->t_lock, flags);
1358
1359 /* if the receiver has been "Exiting", the last thing it did
1360 * was set the conn state to "StandAlone",
1361 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
1362 * and receiver thread will be "started".
1363 * drbd_thread_start needs to set "Restarting" in that case.
1364 * t_state check and assignment needs to be within the same spinlock,
1365 * so either thread_start sees Exiting, and can remap to Restarting,
1366 * or thread_start see None, and can proceed as normal.
1367 */
1368
1369 if (thi->t_state == Restarting) {
1370 dev_info(DEV, "Restarting %s\n", current->comm);
1371 thi->t_state = Running;
1372 spin_unlock_irqrestore(&thi->t_lock, flags);
1373 goto restart;
1374 }
1375
1376 thi->task = NULL;
1377 thi->t_state = None;
1378 smp_mb();
1379 complete(&thi->stop);
1380 spin_unlock_irqrestore(&thi->t_lock, flags);
1381
1382 dev_info(DEV, "Terminating %s\n", current->comm);
1383
1384 /* Release mod reference taken when thread was started */
1385 module_put(THIS_MODULE);
1386 return retval;
1387}
1388
1389static void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi,
1390 int (*func) (struct drbd_thread *))
1391{
1392 spin_lock_init(&thi->t_lock);
1393 thi->task = NULL;
1394 thi->t_state = None;
1395 thi->function = func;
1396 thi->mdev = mdev;
1397}
1398
1399int drbd_thread_start(struct drbd_thread *thi)
1400{
1401 struct drbd_conf *mdev = thi->mdev;
1402 struct task_struct *nt;
1403 unsigned long flags;
1404
1405 const char *me =
1406 thi == &mdev->receiver ? "receiver" :
1407 thi == &mdev->asender ? "asender" :
1408 thi == &mdev->worker ? "worker" : "NONSENSE";
1409
1410 /* is used from state engine doing drbd_thread_stop_nowait,
1411 * while holding the req lock irqsave */
1412 spin_lock_irqsave(&thi->t_lock, flags);
1413
1414 switch (thi->t_state) {
1415 case None:
1416 dev_info(DEV, "Starting %s thread (from %s [%d])\n",
1417 me, current->comm, current->pid);
1418
1419 /* Get ref on module for thread - this is released when thread exits */
1420 if (!try_module_get(THIS_MODULE)) {
1421 dev_err(DEV, "Failed to get module reference in drbd_thread_start\n");
1422 spin_unlock_irqrestore(&thi->t_lock, flags);
1423 return FALSE;
1424 }
1425
1426 init_completion(&thi->stop);
1427 D_ASSERT(thi->task == NULL);
1428 thi->reset_cpu_mask = 1;
1429 thi->t_state = Running;
1430 spin_unlock_irqrestore(&thi->t_lock, flags);
1431 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
1432
1433 nt = kthread_create(drbd_thread_setup, (void *) thi,
1434 "drbd%d_%s", mdev_to_minor(mdev), me);
1435
1436 if (IS_ERR(nt)) {
1437 dev_err(DEV, "Couldn't start thread\n");
1438
1439 module_put(THIS_MODULE);
1440 return FALSE;
1441 }
1442 spin_lock_irqsave(&thi->t_lock, flags);
1443 thi->task = nt;
1444 thi->t_state = Running;
1445 spin_unlock_irqrestore(&thi->t_lock, flags);
1446 wake_up_process(nt);
1447 break;
1448 case Exiting:
1449 thi->t_state = Restarting;
1450 dev_info(DEV, "Restarting %s thread (from %s [%d])\n",
1451 me, current->comm, current->pid);
1452 /* fall through */
1453 case Running:
1454 case Restarting:
1455 default:
1456 spin_unlock_irqrestore(&thi->t_lock, flags);
1457 break;
1458 }
1459
1460 return TRUE;
1461}
1462
1463
1464void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
1465{
1466 unsigned long flags;
1467
1468 enum drbd_thread_state ns = restart ? Restarting : Exiting;
1469
1470 /* may be called from state engine, holding the req lock irqsave */
1471 spin_lock_irqsave(&thi->t_lock, flags);
1472
1473 if (thi->t_state == None) {
1474 spin_unlock_irqrestore(&thi->t_lock, flags);
1475 if (restart)
1476 drbd_thread_start(thi);
1477 return;
1478 }
1479
1480 if (thi->t_state != ns) {
1481 if (thi->task == NULL) {
1482 spin_unlock_irqrestore(&thi->t_lock, flags);
1483 return;
1484 }
1485
1486 thi->t_state = ns;
1487 smp_mb();
1488 init_completion(&thi->stop);
1489 if (thi->task != current)
1490 force_sig(DRBD_SIGKILL, thi->task);
1491
1492 }
1493
1494 spin_unlock_irqrestore(&thi->t_lock, flags);
1495
1496 if (wait)
1497 wait_for_completion(&thi->stop);
1498}
1499
1500#ifdef CONFIG_SMP
1501/**
1502 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
1503 * @mdev: DRBD device.
1504 *
1505 * Forces all threads of a device onto the same CPU. This is beneficial for
1506 * DRBD's performance. May be overwritten by user's configuration.
1507 */
1508void drbd_calc_cpu_mask(struct drbd_conf *mdev)
1509{
1510 int ord, cpu;
1511
1512 /* user override. */
1513 if (cpumask_weight(mdev->cpu_mask))
1514 return;
1515
1516 ord = mdev_to_minor(mdev) % cpumask_weight(cpu_online_mask);
1517 for_each_online_cpu(cpu) {
1518 if (ord-- == 0) {
1519 cpumask_set_cpu(cpu, mdev->cpu_mask);
1520 return;
1521 }
1522 }
1523 /* should not be reached */
1524 cpumask_setall(mdev->cpu_mask);
1525}
1526
1527/**
1528 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
1529 * @mdev: DRBD device.
1530 *
1531 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
1532 * prematurely.
1533 */
1534void drbd_thread_current_set_cpu(struct drbd_conf *mdev)
1535{
1536 struct task_struct *p = current;
1537 struct drbd_thread *thi =
1538 p == mdev->asender.task ? &mdev->asender :
1539 p == mdev->receiver.task ? &mdev->receiver :
1540 p == mdev->worker.task ? &mdev->worker :
1541 NULL;
1542 ERR_IF(thi == NULL)
1543 return;
1544 if (!thi->reset_cpu_mask)
1545 return;
1546 thi->reset_cpu_mask = 0;
1547 set_cpus_allowed_ptr(p, mdev->cpu_mask);
1548}
1549#endif
1550
1551/* the appropriate socket mutex must be held already */
1552int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1553 enum drbd_packets cmd, struct p_header *h,
1554 size_t size, unsigned msg_flags)
1555{
1556 int sent, ok;
1557
1558 ERR_IF(!h) return FALSE;
1559 ERR_IF(!size) return FALSE;
1560
1561 h->magic = BE_DRBD_MAGIC;
1562 h->command = cpu_to_be16(cmd);
1563 h->length = cpu_to_be16(size-sizeof(struct p_header));
1564
Philipp Reisnerb411b362009-09-25 16:07:19 -07001565 sent = drbd_send(mdev, sock, h, size, msg_flags);
1566
1567 ok = (sent == size);
1568 if (!ok)
1569 dev_err(DEV, "short sent %s size=%d sent=%d\n",
1570 cmdname(cmd), (int)size, sent);
1571 return ok;
1572}
1573
1574/* don't pass the socket. we may only look at it
1575 * when we hold the appropriate socket mutex.
1576 */
1577int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1578 enum drbd_packets cmd, struct p_header *h, size_t size)
1579{
1580 int ok = 0;
1581 struct socket *sock;
1582
1583 if (use_data_socket) {
1584 mutex_lock(&mdev->data.mutex);
1585 sock = mdev->data.socket;
1586 } else {
1587 mutex_lock(&mdev->meta.mutex);
1588 sock = mdev->meta.socket;
1589 }
1590
1591 /* drbd_disconnect() could have called drbd_free_sock()
1592 * while we were waiting in down()... */
1593 if (likely(sock != NULL))
1594 ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0);
1595
1596 if (use_data_socket)
1597 mutex_unlock(&mdev->data.mutex);
1598 else
1599 mutex_unlock(&mdev->meta.mutex);
1600 return ok;
1601}
1602
1603int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
1604 size_t size)
1605{
1606 struct p_header h;
1607 int ok;
1608
1609 h.magic = BE_DRBD_MAGIC;
1610 h.command = cpu_to_be16(cmd);
1611 h.length = cpu_to_be16(size);
1612
1613 if (!drbd_get_data_sock(mdev))
1614 return 0;
1615
Philipp Reisnerb411b362009-09-25 16:07:19 -07001616 ok = (sizeof(h) ==
1617 drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0));
1618 ok = ok && (size ==
1619 drbd_send(mdev, mdev->data.socket, data, size, 0));
1620
1621 drbd_put_data_sock(mdev);
1622
1623 return ok;
1624}
1625
1626int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc)
1627{
1628 struct p_rs_param_89 *p;
1629 struct socket *sock;
1630 int size, rv;
1631 const int apv = mdev->agreed_pro_version;
1632
1633 size = apv <= 87 ? sizeof(struct p_rs_param)
1634 : apv == 88 ? sizeof(struct p_rs_param)
1635 + strlen(mdev->sync_conf.verify_alg) + 1
1636 : /* 89 */ sizeof(struct p_rs_param_89);
1637
1638 /* used from admin command context and receiver/worker context.
1639 * to avoid kmalloc, grab the socket right here,
1640 * then use the pre-allocated sbuf there */
1641 mutex_lock(&mdev->data.mutex);
1642 sock = mdev->data.socket;
1643
1644 if (likely(sock != NULL)) {
1645 enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
1646
1647 p = &mdev->data.sbuf.rs_param_89;
1648
1649 /* initialize verify_alg and csums_alg */
1650 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
1651
1652 p->rate = cpu_to_be32(sc->rate);
1653
1654 if (apv >= 88)
1655 strcpy(p->verify_alg, mdev->sync_conf.verify_alg);
1656 if (apv >= 89)
1657 strcpy(p->csums_alg, mdev->sync_conf.csums_alg);
1658
1659 rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
1660 } else
1661 rv = 0; /* not ok */
1662
1663 mutex_unlock(&mdev->data.mutex);
1664
1665 return rv;
1666}
1667
1668int drbd_send_protocol(struct drbd_conf *mdev)
1669{
1670 struct p_protocol *p;
1671 int size, rv;
1672
1673 size = sizeof(struct p_protocol);
1674
1675 if (mdev->agreed_pro_version >= 87)
1676 size += strlen(mdev->net_conf->integrity_alg) + 1;
1677
1678 /* we must not recurse into our own queue,
1679 * as that is blocked during handshake */
1680 p = kmalloc(size, GFP_NOIO);
1681 if (p == NULL)
1682 return 0;
1683
1684 p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol);
1685 p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p);
1686 p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p);
1687 p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p);
1688 p->want_lose = cpu_to_be32(mdev->net_conf->want_lose);
1689 p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries);
1690
1691 if (mdev->agreed_pro_version >= 87)
1692 strcpy(p->integrity_alg, mdev->net_conf->integrity_alg);
1693
1694 rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL,
1695 (struct p_header *)p, size);
1696 kfree(p);
1697 return rv;
1698}
1699
1700int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
1701{
1702 struct p_uuids p;
1703 int i;
1704
1705 if (!get_ldev_if_state(mdev, D_NEGOTIATING))
1706 return 1;
1707
1708 for (i = UI_CURRENT; i < UI_SIZE; i++)
1709 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
1710
1711 mdev->comm_bm_set = drbd_bm_total_weight(mdev);
1712 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
1713 uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
1714 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
1715 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
1716 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
1717
1718 put_ldev(mdev);
1719
1720 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS,
1721 (struct p_header *)&p, sizeof(p));
1722}
1723
1724int drbd_send_uuids(struct drbd_conf *mdev)
1725{
1726 return _drbd_send_uuids(mdev, 0);
1727}
1728
1729int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
1730{
1731 return _drbd_send_uuids(mdev, 8);
1732}
1733
1734
1735int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val)
1736{
1737 struct p_rs_uuid p;
1738
1739 p.uuid = cpu_to_be64(val);
1740
1741 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID,
1742 (struct p_header *)&p, sizeof(p));
1743}
1744
1745int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply)
1746{
1747 struct p_sizes p;
1748 sector_t d_size, u_size;
1749 int q_order_type;
1750 int ok;
1751
1752 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
1753 D_ASSERT(mdev->ldev->backing_bdev);
1754 d_size = drbd_get_max_capacity(mdev->ldev);
1755 u_size = mdev->ldev->dc.disk_size;
1756 q_order_type = drbd_queue_order_type(mdev);
1757 p.queue_order_type = cpu_to_be32(drbd_queue_order_type(mdev));
1758 put_ldev(mdev);
1759 } else {
1760 d_size = 0;
1761 u_size = 0;
1762 q_order_type = QUEUE_ORDERED_NONE;
1763 }
1764
1765 p.d_size = cpu_to_be64(d_size);
1766 p.u_size = cpu_to_be64(u_size);
1767 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
1768 p.max_segment_size = cpu_to_be32(queue_max_segment_size(mdev->rq_queue));
1769 p.queue_order_type = cpu_to_be32(q_order_type);
1770
1771 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES,
1772 (struct p_header *)&p, sizeof(p));
1773 return ok;
1774}
1775
1776/**
1777 * drbd_send_state() - Sends the drbd state to the peer
1778 * @mdev: DRBD device.
1779 */
1780int drbd_send_state(struct drbd_conf *mdev)
1781{
1782 struct socket *sock;
1783 struct p_state p;
1784 int ok = 0;
1785
1786 /* Grab state lock so we wont send state if we're in the middle
1787 * of a cluster wide state change on another thread */
1788 drbd_state_lock(mdev);
1789
1790 mutex_lock(&mdev->data.mutex);
1791
1792 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
1793 sock = mdev->data.socket;
1794
1795 if (likely(sock != NULL)) {
1796 ok = _drbd_send_cmd(mdev, sock, P_STATE,
1797 (struct p_header *)&p, sizeof(p), 0);
1798 }
1799
1800 mutex_unlock(&mdev->data.mutex);
1801
1802 drbd_state_unlock(mdev);
1803 return ok;
1804}
1805
1806int drbd_send_state_req(struct drbd_conf *mdev,
1807 union drbd_state mask, union drbd_state val)
1808{
1809 struct p_req_state p;
1810
1811 p.mask = cpu_to_be32(mask.i);
1812 p.val = cpu_to_be32(val.i);
1813
1814 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ,
1815 (struct p_header *)&p, sizeof(p));
1816}
1817
1818int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode)
1819{
1820 struct p_req_state_reply p;
1821
1822 p.retcode = cpu_to_be32(retcode);
1823
1824 return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY,
1825 (struct p_header *)&p, sizeof(p));
1826}
1827
1828int fill_bitmap_rle_bits(struct drbd_conf *mdev,
1829 struct p_compressed_bm *p,
1830 struct bm_xfer_ctx *c)
1831{
1832 struct bitstream bs;
1833 unsigned long plain_bits;
1834 unsigned long tmp;
1835 unsigned long rl;
1836 unsigned len;
1837 unsigned toggle;
1838 int bits;
1839
1840 /* may we use this feature? */
1841 if ((mdev->sync_conf.use_rle == 0) ||
1842 (mdev->agreed_pro_version < 90))
1843 return 0;
1844
1845 if (c->bit_offset >= c->bm_bits)
1846 return 0; /* nothing to do. */
1847
1848 /* use at most thus many bytes */
1849 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
1850 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
1851 /* plain bits covered in this code string */
1852 plain_bits = 0;
1853
1854 /* p->encoding & 0x80 stores whether the first run length is set.
1855 * bit offset is implicit.
1856 * start with toggle == 2 to be able to tell the first iteration */
1857 toggle = 2;
1858
1859 /* see how much plain bits we can stuff into one packet
1860 * using RLE and VLI. */
1861 do {
1862 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
1863 : _drbd_bm_find_next(mdev, c->bit_offset);
1864 if (tmp == -1UL)
1865 tmp = c->bm_bits;
1866 rl = tmp - c->bit_offset;
1867
1868 if (toggle == 2) { /* first iteration */
1869 if (rl == 0) {
1870 /* the first checked bit was set,
1871 * store start value, */
1872 DCBP_set_start(p, 1);
1873 /* but skip encoding of zero run length */
1874 toggle = !toggle;
1875 continue;
1876 }
1877 DCBP_set_start(p, 0);
1878 }
1879
1880 /* paranoia: catch zero runlength.
1881 * can only happen if bitmap is modified while we scan it. */
1882 if (rl == 0) {
1883 dev_err(DEV, "unexpected zero runlength while encoding bitmap "
1884 "t:%u bo:%lu\n", toggle, c->bit_offset);
1885 return -1;
1886 }
1887
1888 bits = vli_encode_bits(&bs, rl);
1889 if (bits == -ENOBUFS) /* buffer full */
1890 break;
1891 if (bits <= 0) {
1892 dev_err(DEV, "error while encoding bitmap: %d\n", bits);
1893 return 0;
1894 }
1895
1896 toggle = !toggle;
1897 plain_bits += rl;
1898 c->bit_offset = tmp;
1899 } while (c->bit_offset < c->bm_bits);
1900
1901 len = bs.cur.b - p->code + !!bs.cur.bit;
1902
1903 if (plain_bits < (len << 3)) {
1904 /* incompressible with this method.
1905 * we need to rewind both word and bit position. */
1906 c->bit_offset -= plain_bits;
1907 bm_xfer_ctx_bit_to_word_offset(c);
1908 c->bit_offset = c->word_offset * BITS_PER_LONG;
1909 return 0;
1910 }
1911
1912 /* RLE + VLI was able to compress it just fine.
1913 * update c->word_offset. */
1914 bm_xfer_ctx_bit_to_word_offset(c);
1915
1916 /* store pad_bits */
1917 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
1918
1919 return len;
1920}
1921
1922enum { OK, FAILED, DONE }
1923send_bitmap_rle_or_plain(struct drbd_conf *mdev,
1924 struct p_header *h, struct bm_xfer_ctx *c)
1925{
1926 struct p_compressed_bm *p = (void*)h;
1927 unsigned long num_words;
1928 int len;
1929 int ok;
1930
1931 len = fill_bitmap_rle_bits(mdev, p, c);
1932
1933 if (len < 0)
1934 return FAILED;
1935
1936 if (len) {
1937 DCBP_set_code(p, RLE_VLI_Bits);
1938 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h,
1939 sizeof(*p) + len, 0);
1940
1941 c->packets[0]++;
1942 c->bytes[0] += sizeof(*p) + len;
1943
1944 if (c->bit_offset >= c->bm_bits)
1945 len = 0; /* DONE */
1946 } else {
1947 /* was not compressible.
1948 * send a buffer full of plain text bits instead. */
1949 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
1950 len = num_words * sizeof(long);
1951 if (len)
1952 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
1953 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP,
1954 h, sizeof(struct p_header) + len, 0);
1955 c->word_offset += num_words;
1956 c->bit_offset = c->word_offset * BITS_PER_LONG;
1957
1958 c->packets[1]++;
1959 c->bytes[1] += sizeof(struct p_header) + len;
1960
1961 if (c->bit_offset > c->bm_bits)
1962 c->bit_offset = c->bm_bits;
1963 }
1964 ok = ok ? ((len == 0) ? DONE : OK) : FAILED;
1965
1966 if (ok == DONE)
1967 INFO_bm_xfer_stats(mdev, "send", c);
1968 return ok;
1969}
1970
1971/* See the comment at receive_bitmap() */
1972int _drbd_send_bitmap(struct drbd_conf *mdev)
1973{
1974 struct bm_xfer_ctx c;
1975 struct p_header *p;
1976 int ret;
1977
1978 ERR_IF(!mdev->bitmap) return FALSE;
1979
1980 /* maybe we should use some per thread scratch page,
1981 * and allocate that during initial device creation? */
1982 p = (struct p_header *) __get_free_page(GFP_NOIO);
1983 if (!p) {
1984 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
1985 return FALSE;
1986 }
1987
1988 if (get_ldev(mdev)) {
1989 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
1990 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
1991 drbd_bm_set_all(mdev);
1992 if (drbd_bm_write(mdev)) {
1993 /* write_bm did fail! Leave full sync flag set in Meta P_DATA
1994 * but otherwise process as per normal - need to tell other
1995 * side that a full resync is required! */
1996 dev_err(DEV, "Failed to write bitmap to disk!\n");
1997 } else {
1998 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
1999 drbd_md_sync(mdev);
2000 }
2001 }
2002 put_ldev(mdev);
2003 }
2004
2005 c = (struct bm_xfer_ctx) {
2006 .bm_bits = drbd_bm_bits(mdev),
2007 .bm_words = drbd_bm_words(mdev),
2008 };
2009
2010 do {
2011 ret = send_bitmap_rle_or_plain(mdev, p, &c);
2012 } while (ret == OK);
2013
2014 free_page((unsigned long) p);
2015 return (ret == DONE);
2016}
2017
2018int drbd_send_bitmap(struct drbd_conf *mdev)
2019{
2020 int err;
2021
2022 if (!drbd_get_data_sock(mdev))
2023 return -1;
2024 err = !_drbd_send_bitmap(mdev);
2025 drbd_put_data_sock(mdev);
2026 return err;
2027}
2028
2029int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
2030{
2031 int ok;
2032 struct p_barrier_ack p;
2033
2034 p.barrier = barrier_nr;
2035 p.set_size = cpu_to_be32(set_size);
2036
2037 if (mdev->state.conn < C_CONNECTED)
2038 return FALSE;
2039 ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK,
2040 (struct p_header *)&p, sizeof(p));
2041 return ok;
2042}
2043
2044/**
2045 * _drbd_send_ack() - Sends an ack packet
2046 * @mdev: DRBD device.
2047 * @cmd: Packet command code.
2048 * @sector: sector, needs to be in big endian byte order
2049 * @blksize: size in byte, needs to be in big endian byte order
2050 * @block_id: Id, big endian byte order
2051 */
2052static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
2053 u64 sector,
2054 u32 blksize,
2055 u64 block_id)
2056{
2057 int ok;
2058 struct p_block_ack p;
2059
2060 p.sector = sector;
2061 p.block_id = block_id;
2062 p.blksize = blksize;
2063 p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq));
2064
2065 if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED)
2066 return FALSE;
2067 ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd,
2068 (struct p_header *)&p, sizeof(p));
2069 return ok;
2070}
2071
2072int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
2073 struct p_data *dp)
2074{
2075 const int header_size = sizeof(struct p_data)
2076 - sizeof(struct p_header);
2077 int data_size = ((struct p_header *)dp)->length - header_size;
2078
2079 return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
2080 dp->block_id);
2081}
2082
2083int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
2084 struct p_block_req *rp)
2085{
2086 return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
2087}
2088
2089/**
2090 * drbd_send_ack() - Sends an ack packet
2091 * @mdev: DRBD device.
2092 * @cmd: Packet command code.
2093 * @e: Epoch entry.
2094 */
2095int drbd_send_ack(struct drbd_conf *mdev,
2096 enum drbd_packets cmd, struct drbd_epoch_entry *e)
2097{
2098 return _drbd_send_ack(mdev, cmd,
2099 cpu_to_be64(e->sector),
2100 cpu_to_be32(e->size),
2101 e->block_id);
2102}
2103
2104/* This function misuses the block_id field to signal if the blocks
2105 * are is sync or not. */
2106int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
2107 sector_t sector, int blksize, u64 block_id)
2108{
2109 return _drbd_send_ack(mdev, cmd,
2110 cpu_to_be64(sector),
2111 cpu_to_be32(blksize),
2112 cpu_to_be64(block_id));
2113}
2114
2115int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
2116 sector_t sector, int size, u64 block_id)
2117{
2118 int ok;
2119 struct p_block_req p;
2120
2121 p.sector = cpu_to_be64(sector);
2122 p.block_id = block_id;
2123 p.blksize = cpu_to_be32(size);
2124
2125 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd,
2126 (struct p_header *)&p, sizeof(p));
2127 return ok;
2128}
2129
2130int drbd_send_drequest_csum(struct drbd_conf *mdev,
2131 sector_t sector, int size,
2132 void *digest, int digest_size,
2133 enum drbd_packets cmd)
2134{
2135 int ok;
2136 struct p_block_req p;
2137
2138 p.sector = cpu_to_be64(sector);
2139 p.block_id = BE_DRBD_MAGIC + 0xbeef;
2140 p.blksize = cpu_to_be32(size);
2141
2142 p.head.magic = BE_DRBD_MAGIC;
2143 p.head.command = cpu_to_be16(cmd);
2144 p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header) + digest_size);
2145
2146 mutex_lock(&mdev->data.mutex);
2147
2148 ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0));
2149 ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0));
2150
2151 mutex_unlock(&mdev->data.mutex);
2152
2153 return ok;
2154}
2155
2156int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
2157{
2158 int ok;
2159 struct p_block_req p;
2160
2161 p.sector = cpu_to_be64(sector);
2162 p.block_id = BE_DRBD_MAGIC + 0xbabe;
2163 p.blksize = cpu_to_be32(size);
2164
2165 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST,
2166 (struct p_header *)&p, sizeof(p));
2167 return ok;
2168}
2169
2170/* called on sndtimeo
2171 * returns FALSE if we should retry,
2172 * TRUE if we think connection is dead
2173 */
2174static int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock)
2175{
2176 int drop_it;
2177 /* long elapsed = (long)(jiffies - mdev->last_received); */
2178
2179 drop_it = mdev->meta.socket == sock
2180 || !mdev->asender.task
2181 || get_t_state(&mdev->asender) != Running
2182 || mdev->state.conn < C_CONNECTED;
2183
2184 if (drop_it)
2185 return TRUE;
2186
2187 drop_it = !--mdev->ko_count;
2188 if (!drop_it) {
2189 dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
2190 current->comm, current->pid, mdev->ko_count);
2191 request_ping(mdev);
2192 }
2193
2194 return drop_it; /* && (mdev->state == R_PRIMARY) */;
2195}
2196
2197/* The idea of sendpage seems to be to put some kind of reference
2198 * to the page into the skb, and to hand it over to the NIC. In
2199 * this process get_page() gets called.
2200 *
2201 * As soon as the page was really sent over the network put_page()
2202 * gets called by some part of the network layer. [ NIC driver? ]
2203 *
2204 * [ get_page() / put_page() increment/decrement the count. If count
2205 * reaches 0 the page will be freed. ]
2206 *
2207 * This works nicely with pages from FSs.
2208 * But this means that in protocol A we might signal IO completion too early!
2209 *
2210 * In order not to corrupt data during a resync we must make sure
2211 * that we do not reuse our own buffer pages (EEs) to early, therefore
2212 * we have the net_ee list.
2213 *
2214 * XFS seems to have problems, still, it submits pages with page_count == 0!
2215 * As a workaround, we disable sendpage on pages
2216 * with page_count == 0 or PageSlab.
2217 */
2218static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
2219 int offset, size_t size)
2220{
2221 int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, 0);
2222 kunmap(page);
2223 if (sent == size)
2224 mdev->send_cnt += size>>9;
2225 return sent == size;
2226}
2227
2228static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
2229 int offset, size_t size)
2230{
2231 mm_segment_t oldfs = get_fs();
2232 int sent, ok;
2233 int len = size;
2234
2235 /* e.g. XFS meta- & log-data is in slab pages, which have a
2236 * page_count of 0 and/or have PageSlab() set.
2237 * we cannot use send_page for those, as that does get_page();
2238 * put_page(); and would cause either a VM_BUG directly, or
2239 * __page_cache_release a page that would actually still be referenced
2240 * by someone, leading to some obscure delayed Oops somewhere else. */
2241 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
2242 return _drbd_no_send_page(mdev, page, offset, size);
2243
2244 drbd_update_congested(mdev);
2245 set_fs(KERNEL_DS);
2246 do {
2247 sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page,
2248 offset, len,
2249 MSG_NOSIGNAL);
2250 if (sent == -EAGAIN) {
2251 if (we_should_drop_the_connection(mdev,
2252 mdev->data.socket))
2253 break;
2254 else
2255 continue;
2256 }
2257 if (sent <= 0) {
2258 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
2259 __func__, (int)size, len, sent);
2260 break;
2261 }
2262 len -= sent;
2263 offset += sent;
2264 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
2265 set_fs(oldfs);
2266 clear_bit(NET_CONGESTED, &mdev->flags);
2267
2268 ok = (len == 0);
2269 if (likely(ok))
2270 mdev->send_cnt += size>>9;
2271 return ok;
2272}
2273
2274static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
2275{
2276 struct bio_vec *bvec;
2277 int i;
2278 __bio_for_each_segment(bvec, bio, i, 0) {
2279 if (!_drbd_no_send_page(mdev, bvec->bv_page,
2280 bvec->bv_offset, bvec->bv_len))
2281 return 0;
2282 }
2283 return 1;
2284}
2285
2286static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
2287{
2288 struct bio_vec *bvec;
2289 int i;
2290 __bio_for_each_segment(bvec, bio, i, 0) {
2291 if (!_drbd_send_page(mdev, bvec->bv_page,
2292 bvec->bv_offset, bvec->bv_len))
2293 return 0;
2294 }
2295
2296 return 1;
2297}
2298
2299/* Used to send write requests
2300 * R_PRIMARY -> Peer (P_DATA)
2301 */
2302int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
2303{
2304 int ok = 1;
2305 struct p_data p;
2306 unsigned int dp_flags = 0;
2307 void *dgb;
2308 int dgs;
2309
2310 if (!drbd_get_data_sock(mdev))
2311 return 0;
2312
2313 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2314 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2315
2316 p.head.magic = BE_DRBD_MAGIC;
2317 p.head.command = cpu_to_be16(P_DATA);
2318 p.head.length =
2319 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + req->size);
2320
2321 p.sector = cpu_to_be64(req->sector);
2322 p.block_id = (unsigned long)req;
2323 p.seq_num = cpu_to_be32(req->seq_num =
2324 atomic_add_return(1, &mdev->packet_seq));
2325 dp_flags = 0;
2326
2327 /* NOTE: no need to check if barriers supported here as we would
2328 * not pass the test in make_request_common in that case
2329 */
2330 if (bio_rw_flagged(req->master_bio, BIO_RW_BARRIER)) {
2331 dev_err(DEV, "ASSERT FAILED would have set DP_HARDBARRIER\n");
2332 /* dp_flags |= DP_HARDBARRIER; */
2333 }
2334 if (bio_rw_flagged(req->master_bio, BIO_RW_SYNCIO))
2335 dp_flags |= DP_RW_SYNC;
2336 /* for now handle SYNCIO and UNPLUG
2337 * as if they still were one and the same flag */
2338 if (bio_rw_flagged(req->master_bio, BIO_RW_UNPLUG))
2339 dp_flags |= DP_RW_SYNC;
2340 if (mdev->state.conn >= C_SYNC_SOURCE &&
2341 mdev->state.conn <= C_PAUSED_SYNC_T)
2342 dp_flags |= DP_MAY_SET_IN_SYNC;
2343
2344 p.dp_flags = cpu_to_be32(dp_flags);
Philipp Reisnerb411b362009-09-25 16:07:19 -07002345 set_bit(UNPLUG_REMOTE, &mdev->flags);
2346 ok = (sizeof(p) ==
2347 drbd_send(mdev, mdev->data.socket, &p, sizeof(p), MSG_MORE));
2348 if (ok && dgs) {
2349 dgb = mdev->int_dig_out;
2350 drbd_csum(mdev, mdev->integrity_w_tfm, req->master_bio, dgb);
2351 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2352 }
2353 if (ok) {
2354 if (mdev->net_conf->wire_protocol == DRBD_PROT_A)
2355 ok = _drbd_send_bio(mdev, req->master_bio);
2356 else
2357 ok = _drbd_send_zc_bio(mdev, req->master_bio);
2358 }
2359
2360 drbd_put_data_sock(mdev);
2361 return ok;
2362}
2363
2364/* answer packet, used to send data back for read requests:
2365 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
2366 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
2367 */
2368int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
2369 struct drbd_epoch_entry *e)
2370{
2371 int ok;
2372 struct p_data p;
2373 void *dgb;
2374 int dgs;
2375
2376 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2377 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2378
2379 p.head.magic = BE_DRBD_MAGIC;
2380 p.head.command = cpu_to_be16(cmd);
2381 p.head.length =
2382 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + e->size);
2383
2384 p.sector = cpu_to_be64(e->sector);
2385 p.block_id = e->block_id;
2386 /* p.seq_num = 0; No sequence numbers here.. */
2387
2388 /* Only called by our kernel thread.
2389 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
2390 * in response to admin command or module unload.
2391 */
2392 if (!drbd_get_data_sock(mdev))
2393 return 0;
2394
Philipp Reisnerb411b362009-09-25 16:07:19 -07002395 ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p,
2396 sizeof(p), MSG_MORE);
2397 if (ok && dgs) {
2398 dgb = mdev->int_dig_out;
2399 drbd_csum(mdev, mdev->integrity_w_tfm, e->private_bio, dgb);
2400 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2401 }
2402 if (ok)
2403 ok = _drbd_send_zc_bio(mdev, e->private_bio);
2404
2405 drbd_put_data_sock(mdev);
2406 return ok;
2407}
2408
2409/*
2410 drbd_send distinguishes two cases:
2411
2412 Packets sent via the data socket "sock"
2413 and packets sent via the meta data socket "msock"
2414
2415 sock msock
2416 -----------------+-------------------------+------------------------------
2417 timeout conf.timeout / 2 conf.timeout / 2
2418 timeout action send a ping via msock Abort communication
2419 and close all sockets
2420*/
2421
2422/*
2423 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
2424 */
2425int drbd_send(struct drbd_conf *mdev, struct socket *sock,
2426 void *buf, size_t size, unsigned msg_flags)
2427{
2428 struct kvec iov;
2429 struct msghdr msg;
2430 int rv, sent = 0;
2431
2432 if (!sock)
2433 return -1000;
2434
2435 /* THINK if (signal_pending) return ... ? */
2436
2437 iov.iov_base = buf;
2438 iov.iov_len = size;
2439
2440 msg.msg_name = NULL;
2441 msg.msg_namelen = 0;
2442 msg.msg_control = NULL;
2443 msg.msg_controllen = 0;
2444 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
2445
2446 if (sock == mdev->data.socket) {
2447 mdev->ko_count = mdev->net_conf->ko_count;
2448 drbd_update_congested(mdev);
2449 }
2450 do {
2451 /* STRANGE
2452 * tcp_sendmsg does _not_ use its size parameter at all ?
2453 *
2454 * -EAGAIN on timeout, -EINTR on signal.
2455 */
2456/* THINK
2457 * do we need to block DRBD_SIG if sock == &meta.socket ??
2458 * otherwise wake_asender() might interrupt some send_*Ack !
2459 */
2460 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
2461 if (rv == -EAGAIN) {
2462 if (we_should_drop_the_connection(mdev, sock))
2463 break;
2464 else
2465 continue;
2466 }
2467 D_ASSERT(rv != 0);
2468 if (rv == -EINTR) {
2469 flush_signals(current);
2470 rv = 0;
2471 }
2472 if (rv < 0)
2473 break;
2474 sent += rv;
2475 iov.iov_base += rv;
2476 iov.iov_len -= rv;
2477 } while (sent < size);
2478
2479 if (sock == mdev->data.socket)
2480 clear_bit(NET_CONGESTED, &mdev->flags);
2481
2482 if (rv <= 0) {
2483 if (rv != -EAGAIN) {
2484 dev_err(DEV, "%s_sendmsg returned %d\n",
2485 sock == mdev->meta.socket ? "msock" : "sock",
2486 rv);
2487 drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE));
2488 } else
2489 drbd_force_state(mdev, NS(conn, C_TIMEOUT));
2490 }
2491
2492 return sent;
2493}
2494
2495static int drbd_open(struct block_device *bdev, fmode_t mode)
2496{
2497 struct drbd_conf *mdev = bdev->bd_disk->private_data;
2498 unsigned long flags;
2499 int rv = 0;
2500
2501 spin_lock_irqsave(&mdev->req_lock, flags);
2502 /* to have a stable mdev->state.role
2503 * and no race with updating open_cnt */
2504
2505 if (mdev->state.role != R_PRIMARY) {
2506 if (mode & FMODE_WRITE)
2507 rv = -EROFS;
2508 else if (!allow_oos)
2509 rv = -EMEDIUMTYPE;
2510 }
2511
2512 if (!rv)
2513 mdev->open_cnt++;
2514 spin_unlock_irqrestore(&mdev->req_lock, flags);
2515
2516 return rv;
2517}
2518
2519static int drbd_release(struct gendisk *gd, fmode_t mode)
2520{
2521 struct drbd_conf *mdev = gd->private_data;
2522 mdev->open_cnt--;
2523 return 0;
2524}
2525
2526static void drbd_unplug_fn(struct request_queue *q)
2527{
2528 struct drbd_conf *mdev = q->queuedata;
2529
Philipp Reisnerb411b362009-09-25 16:07:19 -07002530 /* unplug FIRST */
2531 spin_lock_irq(q->queue_lock);
2532 blk_remove_plug(q);
2533 spin_unlock_irq(q->queue_lock);
2534
2535 /* only if connected */
2536 spin_lock_irq(&mdev->req_lock);
2537 if (mdev->state.pdsk >= D_INCONSISTENT && mdev->state.conn >= C_CONNECTED) {
2538 D_ASSERT(mdev->state.role == R_PRIMARY);
2539 if (test_and_clear_bit(UNPLUG_REMOTE, &mdev->flags)) {
2540 /* add to the data.work queue,
2541 * unless already queued.
2542 * XXX this might be a good addition to drbd_queue_work
2543 * anyways, to detect "double queuing" ... */
2544 if (list_empty(&mdev->unplug_work.list))
2545 drbd_queue_work(&mdev->data.work,
2546 &mdev->unplug_work);
2547 }
2548 }
2549 spin_unlock_irq(&mdev->req_lock);
2550
2551 if (mdev->state.disk >= D_INCONSISTENT)
2552 drbd_kick_lo(mdev);
2553}
2554
2555static void drbd_set_defaults(struct drbd_conf *mdev)
2556{
2557 mdev->sync_conf.after = DRBD_AFTER_DEF;
2558 mdev->sync_conf.rate = DRBD_RATE_DEF;
2559 mdev->sync_conf.al_extents = DRBD_AL_EXTENTS_DEF;
2560 mdev->state = (union drbd_state) {
2561 { .role = R_SECONDARY,
2562 .peer = R_UNKNOWN,
2563 .conn = C_STANDALONE,
2564 .disk = D_DISKLESS,
2565 .pdsk = D_UNKNOWN,
2566 .susp = 0
2567 } };
2568}
2569
2570void drbd_init_set_defaults(struct drbd_conf *mdev)
2571{
2572 /* the memset(,0,) did most of this.
2573 * note: only assignments, no allocation in here */
2574
2575 drbd_set_defaults(mdev);
2576
2577 /* for now, we do NOT yet support it,
2578 * even though we start some framework
2579 * to eventually support barriers */
2580 set_bit(NO_BARRIER_SUPP, &mdev->flags);
2581
2582 atomic_set(&mdev->ap_bio_cnt, 0);
2583 atomic_set(&mdev->ap_pending_cnt, 0);
2584 atomic_set(&mdev->rs_pending_cnt, 0);
2585 atomic_set(&mdev->unacked_cnt, 0);
2586 atomic_set(&mdev->local_cnt, 0);
2587 atomic_set(&mdev->net_cnt, 0);
2588 atomic_set(&mdev->packet_seq, 0);
2589 atomic_set(&mdev->pp_in_use, 0);
2590
2591 mutex_init(&mdev->md_io_mutex);
2592 mutex_init(&mdev->data.mutex);
2593 mutex_init(&mdev->meta.mutex);
2594 sema_init(&mdev->data.work.s, 0);
2595 sema_init(&mdev->meta.work.s, 0);
2596 mutex_init(&mdev->state_mutex);
2597
2598 spin_lock_init(&mdev->data.work.q_lock);
2599 spin_lock_init(&mdev->meta.work.q_lock);
2600
2601 spin_lock_init(&mdev->al_lock);
2602 spin_lock_init(&mdev->req_lock);
2603 spin_lock_init(&mdev->peer_seq_lock);
2604 spin_lock_init(&mdev->epoch_lock);
2605
2606 INIT_LIST_HEAD(&mdev->active_ee);
2607 INIT_LIST_HEAD(&mdev->sync_ee);
2608 INIT_LIST_HEAD(&mdev->done_ee);
2609 INIT_LIST_HEAD(&mdev->read_ee);
2610 INIT_LIST_HEAD(&mdev->net_ee);
2611 INIT_LIST_HEAD(&mdev->resync_reads);
2612 INIT_LIST_HEAD(&mdev->data.work.q);
2613 INIT_LIST_HEAD(&mdev->meta.work.q);
2614 INIT_LIST_HEAD(&mdev->resync_work.list);
2615 INIT_LIST_HEAD(&mdev->unplug_work.list);
2616 INIT_LIST_HEAD(&mdev->md_sync_work.list);
2617 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
2618 mdev->resync_work.cb = w_resync_inactive;
2619 mdev->unplug_work.cb = w_send_write_hint;
2620 mdev->md_sync_work.cb = w_md_sync;
2621 mdev->bm_io_work.w.cb = w_bitmap_io;
2622 init_timer(&mdev->resync_timer);
2623 init_timer(&mdev->md_sync_timer);
2624 mdev->resync_timer.function = resync_timer_fn;
2625 mdev->resync_timer.data = (unsigned long) mdev;
2626 mdev->md_sync_timer.function = md_sync_timer_fn;
2627 mdev->md_sync_timer.data = (unsigned long) mdev;
2628
2629 init_waitqueue_head(&mdev->misc_wait);
2630 init_waitqueue_head(&mdev->state_wait);
2631 init_waitqueue_head(&mdev->ee_wait);
2632 init_waitqueue_head(&mdev->al_wait);
2633 init_waitqueue_head(&mdev->seq_wait);
2634
2635 drbd_thread_init(mdev, &mdev->receiver, drbdd_init);
2636 drbd_thread_init(mdev, &mdev->worker, drbd_worker);
2637 drbd_thread_init(mdev, &mdev->asender, drbd_asender);
2638
2639 mdev->agreed_pro_version = PRO_VERSION_MAX;
2640 mdev->write_ordering = WO_bio_barrier;
2641 mdev->resync_wenr = LC_FREE;
2642}
2643
2644void drbd_mdev_cleanup(struct drbd_conf *mdev)
2645{
2646 if (mdev->receiver.t_state != None)
2647 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
2648 mdev->receiver.t_state);
2649
2650 /* no need to lock it, I'm the only thread alive */
2651 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
2652 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
2653 mdev->al_writ_cnt =
2654 mdev->bm_writ_cnt =
2655 mdev->read_cnt =
2656 mdev->recv_cnt =
2657 mdev->send_cnt =
2658 mdev->writ_cnt =
2659 mdev->p_size =
2660 mdev->rs_start =
2661 mdev->rs_total =
2662 mdev->rs_failed =
2663 mdev->rs_mark_left =
2664 mdev->rs_mark_time = 0;
2665 D_ASSERT(mdev->net_conf == NULL);
2666
2667 drbd_set_my_capacity(mdev, 0);
2668 if (mdev->bitmap) {
2669 /* maybe never allocated. */
2670 drbd_bm_resize(mdev, 0);
2671 drbd_bm_cleanup(mdev);
2672 }
2673
2674 drbd_free_resources(mdev);
2675
2676 /*
2677 * currently we drbd_init_ee only on module load, so
2678 * we may do drbd_release_ee only on module unload!
2679 */
2680 D_ASSERT(list_empty(&mdev->active_ee));
2681 D_ASSERT(list_empty(&mdev->sync_ee));
2682 D_ASSERT(list_empty(&mdev->done_ee));
2683 D_ASSERT(list_empty(&mdev->read_ee));
2684 D_ASSERT(list_empty(&mdev->net_ee));
2685 D_ASSERT(list_empty(&mdev->resync_reads));
2686 D_ASSERT(list_empty(&mdev->data.work.q));
2687 D_ASSERT(list_empty(&mdev->meta.work.q));
2688 D_ASSERT(list_empty(&mdev->resync_work.list));
2689 D_ASSERT(list_empty(&mdev->unplug_work.list));
2690
2691}
2692
2693
2694static void drbd_destroy_mempools(void)
2695{
2696 struct page *page;
2697
2698 while (drbd_pp_pool) {
2699 page = drbd_pp_pool;
2700 drbd_pp_pool = (struct page *)page_private(page);
2701 __free_page(page);
2702 drbd_pp_vacant--;
2703 }
2704
2705 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
2706
2707 if (drbd_ee_mempool)
2708 mempool_destroy(drbd_ee_mempool);
2709 if (drbd_request_mempool)
2710 mempool_destroy(drbd_request_mempool);
2711 if (drbd_ee_cache)
2712 kmem_cache_destroy(drbd_ee_cache);
2713 if (drbd_request_cache)
2714 kmem_cache_destroy(drbd_request_cache);
2715 if (drbd_bm_ext_cache)
2716 kmem_cache_destroy(drbd_bm_ext_cache);
2717 if (drbd_al_ext_cache)
2718 kmem_cache_destroy(drbd_al_ext_cache);
2719
2720 drbd_ee_mempool = NULL;
2721 drbd_request_mempool = NULL;
2722 drbd_ee_cache = NULL;
2723 drbd_request_cache = NULL;
2724 drbd_bm_ext_cache = NULL;
2725 drbd_al_ext_cache = NULL;
2726
2727 return;
2728}
2729
2730static int drbd_create_mempools(void)
2731{
2732 struct page *page;
2733 const int number = (DRBD_MAX_SEGMENT_SIZE/PAGE_SIZE) * minor_count;
2734 int i;
2735
2736 /* prepare our caches and mempools */
2737 drbd_request_mempool = NULL;
2738 drbd_ee_cache = NULL;
2739 drbd_request_cache = NULL;
2740 drbd_bm_ext_cache = NULL;
2741 drbd_al_ext_cache = NULL;
2742 drbd_pp_pool = NULL;
2743
2744 /* caches */
2745 drbd_request_cache = kmem_cache_create(
2746 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
2747 if (drbd_request_cache == NULL)
2748 goto Enomem;
2749
2750 drbd_ee_cache = kmem_cache_create(
2751 "drbd_ee", sizeof(struct drbd_epoch_entry), 0, 0, NULL);
2752 if (drbd_ee_cache == NULL)
2753 goto Enomem;
2754
2755 drbd_bm_ext_cache = kmem_cache_create(
2756 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
2757 if (drbd_bm_ext_cache == NULL)
2758 goto Enomem;
2759
2760 drbd_al_ext_cache = kmem_cache_create(
2761 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
2762 if (drbd_al_ext_cache == NULL)
2763 goto Enomem;
2764
2765 /* mempools */
2766 drbd_request_mempool = mempool_create(number,
2767 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
2768 if (drbd_request_mempool == NULL)
2769 goto Enomem;
2770
2771 drbd_ee_mempool = mempool_create(number,
2772 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2773 if (drbd_request_mempool == NULL)
2774 goto Enomem;
2775
2776 /* drbd's page pool */
2777 spin_lock_init(&drbd_pp_lock);
2778
2779 for (i = 0; i < number; i++) {
2780 page = alloc_page(GFP_HIGHUSER);
2781 if (!page)
2782 goto Enomem;
2783 set_page_private(page, (unsigned long)drbd_pp_pool);
2784 drbd_pp_pool = page;
2785 }
2786 drbd_pp_vacant = number;
2787
2788 return 0;
2789
2790Enomem:
2791 drbd_destroy_mempools(); /* in case we allocated some */
2792 return -ENOMEM;
2793}
2794
2795static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
2796 void *unused)
2797{
2798 /* just so we have it. you never know what interesting things we
2799 * might want to do here some day...
2800 */
2801
2802 return NOTIFY_DONE;
2803}
2804
2805static struct notifier_block drbd_notifier = {
2806 .notifier_call = drbd_notify_sys,
2807};
2808
2809static void drbd_release_ee_lists(struct drbd_conf *mdev)
2810{
2811 int rr;
2812
2813 rr = drbd_release_ee(mdev, &mdev->active_ee);
2814 if (rr)
2815 dev_err(DEV, "%d EEs in active list found!\n", rr);
2816
2817 rr = drbd_release_ee(mdev, &mdev->sync_ee);
2818 if (rr)
2819 dev_err(DEV, "%d EEs in sync list found!\n", rr);
2820
2821 rr = drbd_release_ee(mdev, &mdev->read_ee);
2822 if (rr)
2823 dev_err(DEV, "%d EEs in read list found!\n", rr);
2824
2825 rr = drbd_release_ee(mdev, &mdev->done_ee);
2826 if (rr)
2827 dev_err(DEV, "%d EEs in done list found!\n", rr);
2828
2829 rr = drbd_release_ee(mdev, &mdev->net_ee);
2830 if (rr)
2831 dev_err(DEV, "%d EEs in net list found!\n", rr);
2832}
2833
2834/* caution. no locking.
2835 * currently only used from module cleanup code. */
2836static void drbd_delete_device(unsigned int minor)
2837{
2838 struct drbd_conf *mdev = minor_to_mdev(minor);
2839
2840 if (!mdev)
2841 return;
2842
2843 /* paranoia asserts */
2844 if (mdev->open_cnt != 0)
2845 dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,
2846 __FILE__ , __LINE__);
2847
2848 ERR_IF (!list_empty(&mdev->data.work.q)) {
2849 struct list_head *lp;
2850 list_for_each(lp, &mdev->data.work.q) {
2851 dev_err(DEV, "lp = %p\n", lp);
2852 }
2853 };
2854 /* end paranoia asserts */
2855
2856 del_gendisk(mdev->vdisk);
2857
2858 /* cleanup stuff that may have been allocated during
2859 * device (re-)configuration or state changes */
2860
2861 if (mdev->this_bdev)
2862 bdput(mdev->this_bdev);
2863
2864 drbd_free_resources(mdev);
2865
2866 drbd_release_ee_lists(mdev);
2867
2868 /* should be free'd on disconnect? */
2869 kfree(mdev->ee_hash);
2870 /*
2871 mdev->ee_hash_s = 0;
2872 mdev->ee_hash = NULL;
2873 */
2874
2875 lc_destroy(mdev->act_log);
2876 lc_destroy(mdev->resync);
2877
2878 kfree(mdev->p_uuid);
2879 /* mdev->p_uuid = NULL; */
2880
2881 kfree(mdev->int_dig_out);
2882 kfree(mdev->int_dig_in);
2883 kfree(mdev->int_dig_vv);
2884
2885 /* cleanup the rest that has been
2886 * allocated from drbd_new_device
2887 * and actually free the mdev itself */
2888 drbd_free_mdev(mdev);
2889}
2890
2891static void drbd_cleanup(void)
2892{
2893 unsigned int i;
2894
2895 unregister_reboot_notifier(&drbd_notifier);
2896
2897 drbd_nl_cleanup();
2898
2899 if (minor_table) {
2900 if (drbd_proc)
2901 remove_proc_entry("drbd", NULL);
2902 i = minor_count;
2903 while (i--)
2904 drbd_delete_device(i);
2905 drbd_destroy_mempools();
2906 }
2907
2908 kfree(minor_table);
2909
2910 unregister_blkdev(DRBD_MAJOR, "drbd");
2911
2912 printk(KERN_INFO "drbd: module cleanup done.\n");
2913}
2914
2915/**
2916 * drbd_congested() - Callback for pdflush
2917 * @congested_data: User data
2918 * @bdi_bits: Bits pdflush is currently interested in
2919 *
2920 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
2921 */
2922static int drbd_congested(void *congested_data, int bdi_bits)
2923{
2924 struct drbd_conf *mdev = congested_data;
2925 struct request_queue *q;
2926 char reason = '-';
2927 int r = 0;
2928
2929 if (!__inc_ap_bio_cond(mdev)) {
2930 /* DRBD has frozen IO */
2931 r = bdi_bits;
2932 reason = 'd';
2933 goto out;
2934 }
2935
2936 if (get_ldev(mdev)) {
2937 q = bdev_get_queue(mdev->ldev->backing_bdev);
2938 r = bdi_congested(&q->backing_dev_info, bdi_bits);
2939 put_ldev(mdev);
2940 if (r)
2941 reason = 'b';
2942 }
2943
2944 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) {
2945 r |= (1 << BDI_async_congested);
2946 reason = reason == 'b' ? 'a' : 'n';
2947 }
2948
2949out:
2950 mdev->congestion_reason = reason;
2951 return r;
2952}
2953
2954struct drbd_conf *drbd_new_device(unsigned int minor)
2955{
2956 struct drbd_conf *mdev;
2957 struct gendisk *disk;
2958 struct request_queue *q;
2959
2960 /* GFP_KERNEL, we are outside of all write-out paths */
2961 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
2962 if (!mdev)
2963 return NULL;
2964 if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL))
2965 goto out_no_cpumask;
2966
2967 mdev->minor = minor;
2968
2969 drbd_init_set_defaults(mdev);
2970
2971 q = blk_alloc_queue(GFP_KERNEL);
2972 if (!q)
2973 goto out_no_q;
2974 mdev->rq_queue = q;
2975 q->queuedata = mdev;
Philipp Reisnerb411b362009-09-25 16:07:19 -07002976
2977 disk = alloc_disk(1);
2978 if (!disk)
2979 goto out_no_disk;
2980 mdev->vdisk = disk;
2981
2982 set_disk_ro(disk, TRUE);
2983
2984 disk->queue = q;
2985 disk->major = DRBD_MAJOR;
2986 disk->first_minor = minor;
2987 disk->fops = &drbd_ops;
2988 sprintf(disk->disk_name, "drbd%d", minor);
2989 disk->private_data = mdev;
2990
2991 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
2992 /* we have no partitions. we contain only ourselves. */
2993 mdev->this_bdev->bd_contains = mdev->this_bdev;
2994
2995 q->backing_dev_info.congested_fn = drbd_congested;
2996 q->backing_dev_info.congested_data = mdev;
2997
2998 blk_queue_make_request(q, drbd_make_request_26);
Lars Ellenberg98ec2862010-01-21 19:33:14 +01002999 blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE);
Philipp Reisnerb411b362009-09-25 16:07:19 -07003000 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
3001 blk_queue_merge_bvec(q, drbd_merge_bvec);
3002 q->queue_lock = &mdev->req_lock; /* needed since we use */
3003 /* plugging on a queue, that actually has no requests! */
3004 q->unplug_fn = drbd_unplug_fn;
3005
3006 mdev->md_io_page = alloc_page(GFP_KERNEL);
3007 if (!mdev->md_io_page)
3008 goto out_no_io_page;
3009
3010 if (drbd_bm_init(mdev))
3011 goto out_no_bitmap;
3012 /* no need to lock access, we are still initializing this minor device. */
3013 if (!tl_init(mdev))
3014 goto out_no_tl;
3015
3016 mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL);
3017 if (!mdev->app_reads_hash)
3018 goto out_no_app_reads;
3019
3020 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
3021 if (!mdev->current_epoch)
3022 goto out_no_epoch;
3023
3024 INIT_LIST_HEAD(&mdev->current_epoch->list);
3025 mdev->epochs = 1;
3026
3027 return mdev;
3028
3029/* out_whatever_else:
3030 kfree(mdev->current_epoch); */
3031out_no_epoch:
3032 kfree(mdev->app_reads_hash);
3033out_no_app_reads:
3034 tl_cleanup(mdev);
3035out_no_tl:
3036 drbd_bm_cleanup(mdev);
3037out_no_bitmap:
3038 __free_page(mdev->md_io_page);
3039out_no_io_page:
3040 put_disk(disk);
3041out_no_disk:
3042 blk_cleanup_queue(q);
3043out_no_q:
3044 free_cpumask_var(mdev->cpu_mask);
3045out_no_cpumask:
3046 kfree(mdev);
3047 return NULL;
3048}
3049
3050/* counterpart of drbd_new_device.
3051 * last part of drbd_delete_device. */
3052void drbd_free_mdev(struct drbd_conf *mdev)
3053{
3054 kfree(mdev->current_epoch);
3055 kfree(mdev->app_reads_hash);
3056 tl_cleanup(mdev);
3057 if (mdev->bitmap) /* should no longer be there. */
3058 drbd_bm_cleanup(mdev);
3059 __free_page(mdev->md_io_page);
3060 put_disk(mdev->vdisk);
3061 blk_cleanup_queue(mdev->rq_queue);
3062 free_cpumask_var(mdev->cpu_mask);
3063 kfree(mdev);
3064}
3065
3066
3067int __init drbd_init(void)
3068{
3069 int err;
3070
3071 if (sizeof(struct p_handshake) != 80) {
3072 printk(KERN_ERR
3073 "drbd: never change the size or layout "
3074 "of the HandShake packet.\n");
3075 return -EINVAL;
3076 }
3077
3078 if (1 > minor_count || minor_count > 255) {
3079 printk(KERN_ERR
3080 "drbd: invalid minor_count (%d)\n", minor_count);
3081#ifdef MODULE
3082 return -EINVAL;
3083#else
3084 minor_count = 8;
3085#endif
3086 }
3087
3088 err = drbd_nl_init();
3089 if (err)
3090 return err;
3091
3092 err = register_blkdev(DRBD_MAJOR, "drbd");
3093 if (err) {
3094 printk(KERN_ERR
3095 "drbd: unable to register block device major %d\n",
3096 DRBD_MAJOR);
3097 return err;
3098 }
3099
3100 register_reboot_notifier(&drbd_notifier);
3101
3102 /*
3103 * allocate all necessary structs
3104 */
3105 err = -ENOMEM;
3106
3107 init_waitqueue_head(&drbd_pp_wait);
3108
3109 drbd_proc = NULL; /* play safe for drbd_cleanup */
3110 minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
3111 GFP_KERNEL);
3112 if (!minor_table)
3113 goto Enomem;
3114
3115 err = drbd_create_mempools();
3116 if (err)
3117 goto Enomem;
3118
3119 drbd_proc = proc_create("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops);
3120 if (!drbd_proc) {
3121 printk(KERN_ERR "drbd: unable to register proc file\n");
3122 goto Enomem;
3123 }
3124
3125 rwlock_init(&global_state_lock);
3126
3127 printk(KERN_INFO "drbd: initialized. "
3128 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
3129 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
3130 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
3131 printk(KERN_INFO "drbd: registered as block device major %d\n",
3132 DRBD_MAJOR);
3133 printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
3134
3135 return 0; /* Success! */
3136
3137Enomem:
3138 drbd_cleanup();
3139 if (err == -ENOMEM)
3140 /* currently always the case */
3141 printk(KERN_ERR "drbd: ran out of memory\n");
3142 else
3143 printk(KERN_ERR "drbd: initialization failure\n");
3144 return err;
3145}
3146
3147void drbd_free_bc(struct drbd_backing_dev *ldev)
3148{
3149 if (ldev == NULL)
3150 return;
3151
3152 bd_release(ldev->backing_bdev);
3153 bd_release(ldev->md_bdev);
3154
3155 fput(ldev->lo_file);
3156 fput(ldev->md_file);
3157
3158 kfree(ldev);
3159}
3160
3161void drbd_free_sock(struct drbd_conf *mdev)
3162{
3163 if (mdev->data.socket) {
3164 kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR);
3165 sock_release(mdev->data.socket);
3166 mdev->data.socket = NULL;
3167 }
3168 if (mdev->meta.socket) {
3169 kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR);
3170 sock_release(mdev->meta.socket);
3171 mdev->meta.socket = NULL;
3172 }
3173}
3174
3175
3176void drbd_free_resources(struct drbd_conf *mdev)
3177{
3178 crypto_free_hash(mdev->csums_tfm);
3179 mdev->csums_tfm = NULL;
3180 crypto_free_hash(mdev->verify_tfm);
3181 mdev->verify_tfm = NULL;
3182 crypto_free_hash(mdev->cram_hmac_tfm);
3183 mdev->cram_hmac_tfm = NULL;
3184 crypto_free_hash(mdev->integrity_w_tfm);
3185 mdev->integrity_w_tfm = NULL;
3186 crypto_free_hash(mdev->integrity_r_tfm);
3187 mdev->integrity_r_tfm = NULL;
3188
3189 drbd_free_sock(mdev);
3190
3191 __no_warn(local,
3192 drbd_free_bc(mdev->ldev);
3193 mdev->ldev = NULL;);
3194}
3195
3196/* meta data management */
3197
3198struct meta_data_on_disk {
3199 u64 la_size; /* last agreed size. */
3200 u64 uuid[UI_SIZE]; /* UUIDs. */
3201 u64 device_uuid;
3202 u64 reserved_u64_1;
3203 u32 flags; /* MDF */
3204 u32 magic;
3205 u32 md_size_sect;
3206 u32 al_offset; /* offset to this block */
3207 u32 al_nr_extents; /* important for restoring the AL */
3208 /* `-- act_log->nr_elements <-- sync_conf.al_extents */
3209 u32 bm_offset; /* offset to the bitmap, from here */
3210 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
3211 u32 reserved_u32[4];
3212
3213} __packed;
3214
3215/**
3216 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
3217 * @mdev: DRBD device.
3218 */
3219void drbd_md_sync(struct drbd_conf *mdev)
3220{
3221 struct meta_data_on_disk *buffer;
3222 sector_t sector;
3223 int i;
3224
3225 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
3226 return;
3227 del_timer(&mdev->md_sync_timer);
3228
3229 /* We use here D_FAILED and not D_ATTACHING because we try to write
3230 * metadata even if we detach due to a disk failure! */
3231 if (!get_ldev_if_state(mdev, D_FAILED))
3232 return;
3233
Philipp Reisnerb411b362009-09-25 16:07:19 -07003234 mutex_lock(&mdev->md_io_mutex);
3235 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3236 memset(buffer, 0, 512);
3237
3238 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
3239 for (i = UI_CURRENT; i < UI_SIZE; i++)
3240 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
3241 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
3242 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
3243
3244 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
3245 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
3246 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
3247 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
3248 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
3249
3250 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
3251
3252 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
3253 sector = mdev->ldev->md.md_offset;
3254
3255 if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
3256 clear_bit(MD_DIRTY, &mdev->flags);
3257 } else {
3258 /* this was a try anyways ... */
3259 dev_err(DEV, "meta data update failed!\n");
3260
3261 drbd_chk_io_error(mdev, 1, TRUE);
3262 }
3263
3264 /* Update mdev->ldev->md.la_size_sect,
3265 * since we updated it on metadata. */
3266 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
3267
3268 mutex_unlock(&mdev->md_io_mutex);
3269 put_ldev(mdev);
3270}
3271
3272/**
3273 * drbd_md_read() - Reads in the meta data super block
3274 * @mdev: DRBD device.
3275 * @bdev: Device from which the meta data should be read in.
3276 *
3277 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_codes in case
3278 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
3279 */
3280int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
3281{
3282 struct meta_data_on_disk *buffer;
3283 int i, rv = NO_ERROR;
3284
3285 if (!get_ldev_if_state(mdev, D_ATTACHING))
3286 return ERR_IO_MD_DISK;
3287
Philipp Reisnerb411b362009-09-25 16:07:19 -07003288 mutex_lock(&mdev->md_io_mutex);
3289 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3290
3291 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
3292 /* NOTE: cant do normal error processing here as this is
3293 called BEFORE disk is attached */
3294 dev_err(DEV, "Error while reading metadata.\n");
3295 rv = ERR_IO_MD_DISK;
3296 goto err;
3297 }
3298
3299 if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) {
3300 dev_err(DEV, "Error while reading metadata, magic not found.\n");
3301 rv = ERR_MD_INVALID;
3302 goto err;
3303 }
3304 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
3305 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
3306 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
3307 rv = ERR_MD_INVALID;
3308 goto err;
3309 }
3310 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
3311 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
3312 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
3313 rv = ERR_MD_INVALID;
3314 goto err;
3315 }
3316 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
3317 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
3318 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
3319 rv = ERR_MD_INVALID;
3320 goto err;
3321 }
3322
3323 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
3324 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
3325 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
3326 rv = ERR_MD_INVALID;
3327 goto err;
3328 }
3329
3330 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
3331 for (i = UI_CURRENT; i < UI_SIZE; i++)
3332 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
3333 bdev->md.flags = be32_to_cpu(buffer->flags);
3334 mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents);
3335 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
3336
3337 if (mdev->sync_conf.al_extents < 7)
3338 mdev->sync_conf.al_extents = 127;
3339
3340 err:
3341 mutex_unlock(&mdev->md_io_mutex);
3342 put_ldev(mdev);
3343
3344 return rv;
3345}
3346
3347/**
3348 * drbd_md_mark_dirty() - Mark meta data super block as dirty
3349 * @mdev: DRBD device.
3350 *
3351 * Call this function if you change anything that should be written to
3352 * the meta-data super block. This function sets MD_DIRTY, and starts a
3353 * timer that ensures that within five seconds you have to call drbd_md_sync().
3354 */
3355void drbd_md_mark_dirty(struct drbd_conf *mdev)
3356{
3357 set_bit(MD_DIRTY, &mdev->flags);
3358 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
3359}
3360
3361
3362static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
3363{
3364 int i;
3365
Jens Axboe6a0afdf2009-10-01 09:04:14 +02003366 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
Philipp Reisnerb411b362009-09-25 16:07:19 -07003367 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
Philipp Reisnerb411b362009-09-25 16:07:19 -07003368}
3369
3370void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3371{
3372 if (idx == UI_CURRENT) {
3373 if (mdev->state.role == R_PRIMARY)
3374 val |= 1;
3375 else
3376 val &= ~((u64)1);
3377
3378 drbd_set_ed_uuid(mdev, val);
3379 }
3380
3381 mdev->ldev->md.uuid[idx] = val;
Philipp Reisnerb411b362009-09-25 16:07:19 -07003382 drbd_md_mark_dirty(mdev);
3383}
3384
3385
3386void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3387{
3388 if (mdev->ldev->md.uuid[idx]) {
3389 drbd_uuid_move_history(mdev);
3390 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
Philipp Reisnerb411b362009-09-25 16:07:19 -07003391 }
3392 _drbd_uuid_set(mdev, idx, val);
3393}
3394
3395/**
3396 * drbd_uuid_new_current() - Creates a new current UUID
3397 * @mdev: DRBD device.
3398 *
3399 * Creates a new current UUID, and rotates the old current UUID into
3400 * the bitmap slot. Causes an incremental resync upon next connect.
3401 */
3402void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
3403{
3404 u64 val;
3405
3406 dev_info(DEV, "Creating new current UUID\n");
3407 D_ASSERT(mdev->ldev->md.uuid[UI_BITMAP] == 0);
3408 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
Philipp Reisnerb411b362009-09-25 16:07:19 -07003409
3410 get_random_bytes(&val, sizeof(u64));
3411 _drbd_uuid_set(mdev, UI_CURRENT, val);
3412}
3413
3414void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
3415{
3416 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
3417 return;
3418
3419 if (val == 0) {
3420 drbd_uuid_move_history(mdev);
3421 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
3422 mdev->ldev->md.uuid[UI_BITMAP] = 0;
Philipp Reisnerb411b362009-09-25 16:07:19 -07003423 } else {
3424 if (mdev->ldev->md.uuid[UI_BITMAP])
3425 dev_warn(DEV, "bm UUID already set");
3426
3427 mdev->ldev->md.uuid[UI_BITMAP] = val;
3428 mdev->ldev->md.uuid[UI_BITMAP] &= ~((u64)1);
3429
Philipp Reisnerb411b362009-09-25 16:07:19 -07003430 }
3431 drbd_md_mark_dirty(mdev);
3432}
3433
3434/**
3435 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3436 * @mdev: DRBD device.
3437 *
3438 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
3439 */
3440int drbd_bmio_set_n_write(struct drbd_conf *mdev)
3441{
3442 int rv = -EIO;
3443
3444 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3445 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
3446 drbd_md_sync(mdev);
3447 drbd_bm_set_all(mdev);
3448
3449 rv = drbd_bm_write(mdev);
3450
3451 if (!rv) {
3452 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
3453 drbd_md_sync(mdev);
3454 }
3455
3456 put_ldev(mdev);
3457 }
3458
3459 return rv;
3460}
3461
3462/**
3463 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3464 * @mdev: DRBD device.
3465 *
3466 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
3467 */
3468int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
3469{
3470 int rv = -EIO;
3471
3472 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3473 drbd_bm_clear_all(mdev);
3474 rv = drbd_bm_write(mdev);
3475 put_ldev(mdev);
3476 }
3477
3478 return rv;
3479}
3480
3481static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3482{
3483 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
3484 int rv;
3485
3486 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
3487
3488 drbd_bm_lock(mdev, work->why);
3489 rv = work->io_fn(mdev);
3490 drbd_bm_unlock(mdev);
3491
3492 clear_bit(BITMAP_IO, &mdev->flags);
3493 wake_up(&mdev->misc_wait);
3494
3495 if (work->done)
3496 work->done(mdev, rv);
3497
3498 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
3499 work->why = NULL;
3500
3501 return 1;
3502}
3503
3504/**
3505 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
3506 * @mdev: DRBD device.
3507 * @io_fn: IO callback to be called when bitmap IO is possible
3508 * @done: callback to be called after the bitmap IO was performed
3509 * @why: Descriptive text of the reason for doing the IO
3510 *
3511 * While IO on the bitmap happens we freeze application IO thus we ensure
3512 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
3513 * called from worker context. It MUST NOT be used while a previous such
3514 * work is still pending!
3515 */
3516void drbd_queue_bitmap_io(struct drbd_conf *mdev,
3517 int (*io_fn)(struct drbd_conf *),
3518 void (*done)(struct drbd_conf *, int),
3519 char *why)
3520{
3521 D_ASSERT(current == mdev->worker.task);
3522
3523 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
3524 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
3525 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
3526 if (mdev->bm_io_work.why)
3527 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
3528 why, mdev->bm_io_work.why);
3529
3530 mdev->bm_io_work.io_fn = io_fn;
3531 mdev->bm_io_work.done = done;
3532 mdev->bm_io_work.why = why;
3533
3534 set_bit(BITMAP_IO, &mdev->flags);
3535 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
3536 if (list_empty(&mdev->bm_io_work.w.list)) {
3537 set_bit(BITMAP_IO_QUEUED, &mdev->flags);
3538 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
3539 } else
3540 dev_err(DEV, "FIXME avoided double queuing bm_io_work\n");
3541 }
3542}
3543
3544/**
3545 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
3546 * @mdev: DRBD device.
3547 * @io_fn: IO callback to be called when bitmap IO is possible
3548 * @why: Descriptive text of the reason for doing the IO
3549 *
3550 * freezes application IO while that the actual IO operations runs. This
3551 * functions MAY NOT be called from worker context.
3552 */
3553int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why)
3554{
3555 int rv;
3556
3557 D_ASSERT(current != mdev->worker.task);
3558
3559 drbd_suspend_io(mdev);
3560
3561 drbd_bm_lock(mdev, why);
3562 rv = io_fn(mdev);
3563 drbd_bm_unlock(mdev);
3564
3565 drbd_resume_io(mdev);
3566
3567 return rv;
3568}
3569
3570void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3571{
3572 if ((mdev->ldev->md.flags & flag) != flag) {
3573 drbd_md_mark_dirty(mdev);
3574 mdev->ldev->md.flags |= flag;
3575 }
3576}
3577
3578void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3579{
3580 if ((mdev->ldev->md.flags & flag) != 0) {
3581 drbd_md_mark_dirty(mdev);
3582 mdev->ldev->md.flags &= ~flag;
3583 }
3584}
3585int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
3586{
3587 return (bdev->md.flags & flag) != 0;
3588}
3589
3590static void md_sync_timer_fn(unsigned long data)
3591{
3592 struct drbd_conf *mdev = (struct drbd_conf *) data;
3593
3594 drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work);
3595}
3596
3597static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3598{
3599 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3600 drbd_md_sync(mdev);
3601
3602 return 1;
3603}
3604
3605#ifdef CONFIG_DRBD_FAULT_INJECTION
3606/* Fault insertion support including random number generator shamelessly
3607 * stolen from kernel/rcutorture.c */
3608struct fault_random_state {
3609 unsigned long state;
3610 unsigned long count;
3611};
3612
3613#define FAULT_RANDOM_MULT 39916801 /* prime */
3614#define FAULT_RANDOM_ADD 479001701 /* prime */
3615#define FAULT_RANDOM_REFRESH 10000
3616
3617/*
3618 * Crude but fast random-number generator. Uses a linear congruential
3619 * generator, with occasional help from get_random_bytes().
3620 */
3621static unsigned long
3622_drbd_fault_random(struct fault_random_state *rsp)
3623{
3624 long refresh;
3625
Roel Kluin49829ea2009-12-15 22:55:44 +01003626 if (!rsp->count--) {
Philipp Reisnerb411b362009-09-25 16:07:19 -07003627 get_random_bytes(&refresh, sizeof(refresh));
3628 rsp->state += refresh;
3629 rsp->count = FAULT_RANDOM_REFRESH;
3630 }
3631 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
3632 return swahw32(rsp->state);
3633}
3634
3635static char *
3636_drbd_fault_str(unsigned int type) {
3637 static char *_faults[] = {
3638 [DRBD_FAULT_MD_WR] = "Meta-data write",
3639 [DRBD_FAULT_MD_RD] = "Meta-data read",
3640 [DRBD_FAULT_RS_WR] = "Resync write",
3641 [DRBD_FAULT_RS_RD] = "Resync read",
3642 [DRBD_FAULT_DT_WR] = "Data write",
3643 [DRBD_FAULT_DT_RD] = "Data read",
3644 [DRBD_FAULT_DT_RA] = "Data read ahead",
3645 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
3646 [DRBD_FAULT_AL_EE] = "EE allocation"
3647 };
3648
3649 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
3650}
3651
3652unsigned int
3653_drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
3654{
3655 static struct fault_random_state rrs = {0, 0};
3656
3657 unsigned int ret = (
3658 (fault_devs == 0 ||
3659 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
3660 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
3661
3662 if (ret) {
3663 fault_count++;
3664
3665 if (printk_ratelimit())
3666 dev_warn(DEV, "***Simulating %s failure\n",
3667 _drbd_fault_str(type));
3668 }
3669
3670 return ret;
3671}
3672#endif
3673
3674const char *drbd_buildtag(void)
3675{
3676 /* DRBD built from external sources has here a reference to the
3677 git hash of the source code. */
3678
3679 static char buildtag[38] = "\0uilt-in";
3680
3681 if (buildtag[0] == 0) {
3682#ifdef CONFIG_MODULES
3683 if (THIS_MODULE != NULL)
3684 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
3685 else
3686#endif
3687 buildtag[0] = 'b';
3688 }
3689
3690 return buildtag;
3691}
3692
3693module_init(drbd_init)
3694module_exit(drbd_cleanup)
3695
Philipp Reisnerb411b362009-09-25 16:07:19 -07003696EXPORT_SYMBOL(drbd_conn_str);
3697EXPORT_SYMBOL(drbd_role_str);
3698EXPORT_SYMBOL(drbd_disk_str);
3699EXPORT_SYMBOL(drbd_set_st_err_str);