4 This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
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>.
10 Thanks to Carter Burden, Bart Grantham and Gennadiy Nerubayev
11 from Logicworks, Inc. for making SDP replication support possible.
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)
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.
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.
29 #include <linux/module.h>
30 #include <linux/drbd.h>
31 #include <asm/uaccess.h>
32 #include <asm/types.h>
34 #include <linux/ctype.h>
35 #include <linux/mutex.h>
37 #include <linux/file.h>
38 #include <linux/proc_fs.h>
39 #include <linux/init.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>
49 #define __KERNEL_SYSCALLS__
50 #include <linux/unistd.h>
51 #include <linux/vmalloc.h>
53 #include <linux/drbd_limits.h>
55 #include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */
59 struct after_state_chg_work {
63 enum chg_state_flags flags;
64 struct completion *done;
67 static DEFINE_MUTEX(drbd_main_mutex);
68 int drbdd_init(struct drbd_thread *);
69 int drbd_worker(struct drbd_thread *);
70 int drbd_asender(struct drbd_thread *);
73 static int drbd_open(struct block_device *bdev, fmode_t mode);
74 static int drbd_release(struct gendisk *gd, fmode_t mode);
75 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused);
76 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
77 union drbd_state ns, enum chg_state_flags flags);
78 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused);
79 static void md_sync_timer_fn(unsigned long data);
80 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused);
81 static int w_go_diskless(struct drbd_conf *mdev, struct drbd_work *w, int unused);
83 MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, "
84 "Lars Ellenberg <lars@linbit.com>");
85 MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION);
86 MODULE_VERSION(REL_VERSION);
87 MODULE_LICENSE("GPL");
88 MODULE_PARM_DESC(minor_count, "Maximum number of drbd devices ("
89 __stringify(DRBD_MINOR_COUNT_MIN) "-" __stringify(DRBD_MINOR_COUNT_MAX) ")");
90 MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR);
92 #include <linux/moduleparam.h>
93 /* allow_open_on_secondary */
94 MODULE_PARM_DESC(allow_oos, "DONT USE!");
95 /* thanks to these macros, if compiled into the kernel (not-module),
96 * this becomes the boot parameter drbd.minor_count */
97 module_param(minor_count, uint, 0444);
98 module_param(disable_sendpage, bool, 0644);
99 module_param(allow_oos, bool, 0);
100 module_param(cn_idx, uint, 0444);
101 module_param(proc_details, int, 0644);
103 #ifdef CONFIG_DRBD_FAULT_INJECTION
106 static int fault_count;
108 /* bitmap of enabled faults */
109 module_param(enable_faults, int, 0664);
110 /* fault rate % value - applies to all enabled faults */
111 module_param(fault_rate, int, 0664);
112 /* count of faults inserted */
113 module_param(fault_count, int, 0664);
114 /* bitmap of devices to insert faults on */
115 module_param(fault_devs, int, 0644);
118 /* module parameter, defined */
119 unsigned int minor_count = DRBD_MINOR_COUNT_DEF;
120 bool disable_sendpage;
122 unsigned int cn_idx = CN_IDX_DRBD;
123 int proc_details; /* Detail level in proc drbd*/
125 /* Module parameter for setting the user mode helper program
126 * to run. Default is /sbin/drbdadm */
127 char usermode_helper[80] = "/sbin/drbdadm";
129 module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644);
131 /* in 2.6.x, our device mapping and config info contains our virtual gendisks
132 * as member "struct gendisk *vdisk;"
134 struct drbd_conf **minor_table;
136 struct kmem_cache *drbd_request_cache;
137 struct kmem_cache *drbd_ee_cache; /* epoch entries */
138 struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */
139 struct kmem_cache *drbd_al_ext_cache; /* activity log extents */
140 mempool_t *drbd_request_mempool;
141 mempool_t *drbd_ee_mempool;
143 /* I do not use a standard mempool, because:
144 1) I want to hand out the pre-allocated objects first.
145 2) I want to be able to interrupt sleeping allocation with a signal.
146 Note: This is a single linked list, the next pointer is the private
147 member of struct page.
149 struct page *drbd_pp_pool;
150 spinlock_t drbd_pp_lock;
152 wait_queue_head_t drbd_pp_wait;
154 DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5);
156 static const struct block_device_operations drbd_ops = {
157 .owner = THIS_MODULE,
159 .release = drbd_release,
162 #define ARRY_SIZE(A) (sizeof(A)/sizeof(A[0]))
165 /* When checking with sparse, and this is an inline function, sparse will
166 give tons of false positives. When this is a real functions sparse works.
168 int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
172 atomic_inc(&mdev->local_cnt);
173 io_allowed = (mdev->state.disk >= mins);
175 if (atomic_dec_and_test(&mdev->local_cnt))
176 wake_up(&mdev->misc_wait);
184 * DOC: The transfer log
186 * The transfer log is a single linked list of &struct drbd_tl_epoch objects.
187 * mdev->newest_tle points to the head, mdev->oldest_tle points to the tail
188 * of the list. There is always at least one &struct drbd_tl_epoch object.
190 * Each &struct drbd_tl_epoch has a circular double linked list of requests
193 static int tl_init(struct drbd_conf *mdev)
195 struct drbd_tl_epoch *b;
197 /* during device minor initialization, we may well use GFP_KERNEL */
198 b = kmalloc(sizeof(struct drbd_tl_epoch), GFP_KERNEL);
201 INIT_LIST_HEAD(&b->requests);
202 INIT_LIST_HEAD(&b->w.list);
206 b->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
208 mdev->oldest_tle = b;
209 mdev->newest_tle = b;
210 INIT_LIST_HEAD(&mdev->out_of_sequence_requests);
211 INIT_LIST_HEAD(&mdev->barrier_acked_requests);
213 mdev->tl_hash = NULL;
219 static void tl_cleanup(struct drbd_conf *mdev)
221 D_ASSERT(mdev->oldest_tle == mdev->newest_tle);
222 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
223 kfree(mdev->oldest_tle);
224 mdev->oldest_tle = NULL;
225 kfree(mdev->unused_spare_tle);
226 mdev->unused_spare_tle = NULL;
227 kfree(mdev->tl_hash);
228 mdev->tl_hash = NULL;
233 * _tl_add_barrier() - Adds a barrier to the transfer log
234 * @mdev: DRBD device.
235 * @new: Barrier to be added before the current head of the TL.
237 * The caller must hold the req_lock.
239 void _tl_add_barrier(struct drbd_conf *mdev, struct drbd_tl_epoch *new)
241 struct drbd_tl_epoch *newest_before;
243 INIT_LIST_HEAD(&new->requests);
244 INIT_LIST_HEAD(&new->w.list);
245 new->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
249 newest_before = mdev->newest_tle;
250 /* never send a barrier number == 0, because that is special-cased
251 * when using TCQ for our write ordering code */
252 new->br_number = (newest_before->br_number+1) ?: 1;
253 if (mdev->newest_tle != new) {
254 mdev->newest_tle->next = new;
255 mdev->newest_tle = new;
260 * tl_release() - Free or recycle the oldest &struct drbd_tl_epoch object of the TL
261 * @mdev: DRBD device.
262 * @barrier_nr: Expected identifier of the DRBD write barrier packet.
263 * @set_size: Expected number of requests before that barrier.
265 * In case the passed barrier_nr or set_size does not match the oldest
266 * &struct drbd_tl_epoch objects this function will cause a termination
269 void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
270 unsigned int set_size)
272 struct drbd_tl_epoch *b, *nob; /* next old barrier */
273 struct list_head *le, *tle;
274 struct drbd_request *r;
276 spin_lock_irq(&mdev->req_lock);
278 b = mdev->oldest_tle;
280 /* first some paranoia code */
282 dev_err(DEV, "BAD! BarrierAck #%u received, but no epoch in tl!?\n",
286 if (b->br_number != barrier_nr) {
287 dev_err(DEV, "BAD! BarrierAck #%u received, expected #%u!\n",
288 barrier_nr, b->br_number);
291 if (b->n_writes != set_size) {
292 dev_err(DEV, "BAD! BarrierAck #%u received with n_writes=%u, expected n_writes=%u!\n",
293 barrier_nr, set_size, b->n_writes);
297 /* Clean up list of requests processed during current epoch */
298 list_for_each_safe(le, tle, &b->requests) {
299 r = list_entry(le, struct drbd_request, tl_requests);
300 _req_mod(r, barrier_acked);
302 /* There could be requests on the list waiting for completion
303 of the write to the local disk. To avoid corruptions of
304 slab's data structures we have to remove the lists head.
306 Also there could have been a barrier ack out of sequence, overtaking
307 the write acks - which would be a bug and violating write ordering.
308 To not deadlock in case we lose connection while such requests are
309 still pending, we need some way to find them for the
310 _req_mode(connection_lost_while_pending).
312 These have been list_move'd to the out_of_sequence_requests list in
313 _req_mod(, barrier_acked) above.
315 list_splice_init(&b->requests, &mdev->barrier_acked_requests);
318 if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags)) {
319 _tl_add_barrier(mdev, b);
321 mdev->oldest_tle = nob;
322 /* if nob == NULL b was the only barrier, and becomes the new
323 barrier. Therefore mdev->oldest_tle points already to b */
325 D_ASSERT(nob != NULL);
326 mdev->oldest_tle = nob;
330 spin_unlock_irq(&mdev->req_lock);
331 dec_ap_pending(mdev);
336 spin_unlock_irq(&mdev->req_lock);
337 drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
342 * _tl_restart() - Walks the transfer log, and applies an action to all requests
343 * @mdev: DRBD device.
344 * @what: The action/event to perform with all request objects
346 * @what might be one of connection_lost_while_pending, resend, fail_frozen_disk_io,
347 * restart_frozen_disk_io.
349 static void _tl_restart(struct drbd_conf *mdev, enum drbd_req_event what)
351 struct drbd_tl_epoch *b, *tmp, **pn;
352 struct list_head *le, *tle, carry_reads;
353 struct drbd_request *req;
354 int rv, n_writes, n_reads;
356 b = mdev->oldest_tle;
357 pn = &mdev->oldest_tle;
361 INIT_LIST_HEAD(&carry_reads);
362 list_for_each_safe(le, tle, &b->requests) {
363 req = list_entry(le, struct drbd_request, tl_requests);
364 rv = _req_mod(req, what);
366 n_writes += (rv & MR_WRITE) >> MR_WRITE_SHIFT;
367 n_reads += (rv & MR_READ) >> MR_READ_SHIFT;
372 if (what == resend) {
373 b->n_writes = n_writes;
374 if (b->w.cb == NULL) {
375 b->w.cb = w_send_barrier;
376 inc_ap_pending(mdev);
377 set_bit(CREATE_BARRIER, &mdev->flags);
380 drbd_queue_work(&mdev->data.work, &b->w);
385 list_add(&carry_reads, &b->requests);
386 /* there could still be requests on that ring list,
387 * in case local io is still pending */
388 list_del(&b->requests);
390 /* dec_ap_pending corresponding to queue_barrier.
391 * the newest barrier may not have been queued yet,
392 * in which case w.cb is still NULL. */
394 dec_ap_pending(mdev);
396 if (b == mdev->newest_tle) {
397 /* recycle, but reinit! */
398 D_ASSERT(tmp == NULL);
399 INIT_LIST_HEAD(&b->requests);
400 list_splice(&carry_reads, &b->requests);
401 INIT_LIST_HEAD(&b->w.list);
403 b->br_number = net_random();
413 list_splice(&carry_reads, &b->requests);
416 /* Actions operating on the disk state, also want to work on
417 requests that got barrier acked. */
419 case fail_frozen_disk_io:
420 case restart_frozen_disk_io:
421 list_for_each_safe(le, tle, &mdev->barrier_acked_requests) {
422 req = list_entry(le, struct drbd_request, tl_requests);
426 case connection_lost_while_pending:
430 dev_err(DEV, "what = %d in _tl_restart()\n", what);
436 * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL
437 * @mdev: DRBD device.
439 * This is called after the connection to the peer was lost. The storage covered
440 * by the requests on the transfer gets marked as our of sync. Called from the
441 * receiver thread and the worker thread.
443 void tl_clear(struct drbd_conf *mdev)
445 struct list_head *le, *tle;
446 struct drbd_request *r;
448 spin_lock_irq(&mdev->req_lock);
450 _tl_restart(mdev, connection_lost_while_pending);
452 /* we expect this list to be empty. */
453 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
455 /* but just in case, clean it up anyways! */
456 list_for_each_safe(le, tle, &mdev->out_of_sequence_requests) {
457 r = list_entry(le, struct drbd_request, tl_requests);
458 /* It would be nice to complete outside of spinlock.
459 * But this is easier for now. */
460 _req_mod(r, connection_lost_while_pending);
463 /* ensure bit indicating barrier is required is clear */
464 clear_bit(CREATE_BARRIER, &mdev->flags);
466 memset(mdev->app_reads_hash, 0, APP_R_HSIZE*sizeof(void *));
468 spin_unlock_irq(&mdev->req_lock);
471 void tl_restart(struct drbd_conf *mdev, enum drbd_req_event what)
473 spin_lock_irq(&mdev->req_lock);
474 _tl_restart(mdev, what);
475 spin_unlock_irq(&mdev->req_lock);
479 * tl_abort_disk_io() - Abort disk I/O for all requests for a certain mdev in the TL
480 * @mdev: DRBD device.
482 void tl_abort_disk_io(struct drbd_conf *mdev)
484 struct drbd_tl_epoch *b;
485 struct list_head *le, *tle;
486 struct drbd_request *req;
488 spin_lock_irq(&mdev->req_lock);
489 b = mdev->oldest_tle;
491 list_for_each_safe(le, tle, &b->requests) {
492 req = list_entry(le, struct drbd_request, tl_requests);
493 if (!(req->rq_state & RQ_LOCAL_PENDING))
495 _req_mod(req, abort_disk_io);
500 list_for_each_safe(le, tle, &mdev->barrier_acked_requests) {
501 req = list_entry(le, struct drbd_request, tl_requests);
502 if (!(req->rq_state & RQ_LOCAL_PENDING))
504 _req_mod(req, abort_disk_io);
507 spin_unlock_irq(&mdev->req_lock);
511 * cl_wide_st_chg() - true if the state change is a cluster wide one
512 * @mdev: DRBD device.
513 * @os: old (current) state.
514 * @ns: new (wanted) state.
516 static int cl_wide_st_chg(struct drbd_conf *mdev,
517 union drbd_state os, union drbd_state ns)
519 return (os.conn >= C_CONNECTED && ns.conn >= C_CONNECTED &&
520 ((os.role != R_PRIMARY && ns.role == R_PRIMARY) ||
521 (os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
522 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S) ||
523 (os.disk != D_FAILED && ns.disk == D_FAILED))) ||
524 (os.conn >= C_CONNECTED && ns.conn == C_DISCONNECTING) ||
525 (os.conn == C_CONNECTED && ns.conn == C_VERIFY_S);
529 drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f,
530 union drbd_state mask, union drbd_state val)
533 union drbd_state os, ns;
534 enum drbd_state_rv rv;
536 spin_lock_irqsave(&mdev->req_lock, flags);
538 ns.i = (os.i & ~mask.i) | val.i;
539 rv = _drbd_set_state(mdev, ns, f, NULL);
541 spin_unlock_irqrestore(&mdev->req_lock, flags);
547 * drbd_force_state() - Impose a change which happens outside our control on our state
548 * @mdev: DRBD device.
549 * @mask: mask of state bits to change.
550 * @val: value of new state bits.
552 void drbd_force_state(struct drbd_conf *mdev,
553 union drbd_state mask, union drbd_state val)
555 drbd_change_state(mdev, CS_HARD, mask, val);
558 static enum drbd_state_rv is_valid_state(struct drbd_conf *, union drbd_state);
559 static enum drbd_state_rv is_valid_state_transition(struct drbd_conf *,
562 enum sanitize_state_warnings {
564 ABORTED_ONLINE_VERIFY,
566 CONNECTION_LOST_NEGOTIATING,
567 IMPLICITLY_UPGRADED_DISK,
568 IMPLICITLY_UPGRADED_PDSK,
570 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
571 union drbd_state ns, enum sanitize_state_warnings *warn);
572 int drbd_send_state_req(struct drbd_conf *,
573 union drbd_state, union drbd_state);
575 static enum drbd_state_rv
576 _req_st_cond(struct drbd_conf *mdev, union drbd_state mask,
577 union drbd_state val)
579 union drbd_state os, ns;
581 enum drbd_state_rv rv;
583 if (test_and_clear_bit(CL_ST_CHG_SUCCESS, &mdev->flags))
584 return SS_CW_SUCCESS;
586 if (test_and_clear_bit(CL_ST_CHG_FAIL, &mdev->flags))
587 return SS_CW_FAILED_BY_PEER;
590 spin_lock_irqsave(&mdev->req_lock, flags);
592 ns.i = (os.i & ~mask.i) | val.i;
593 ns = sanitize_state(mdev, os, ns, NULL);
595 if (!cl_wide_st_chg(mdev, os, ns))
598 rv = is_valid_state(mdev, ns);
599 if (rv == SS_SUCCESS) {
600 rv = is_valid_state_transition(mdev, ns, os);
601 if (rv == SS_SUCCESS)
602 rv = SS_UNKNOWN_ERROR; /* cont waiting, otherwise fail. */
605 spin_unlock_irqrestore(&mdev->req_lock, flags);
611 * drbd_req_state() - Perform an eventually cluster wide state change
612 * @mdev: DRBD device.
613 * @mask: mask of state bits to change.
614 * @val: value of new state bits.
617 * Should not be called directly, use drbd_request_state() or
618 * _drbd_request_state().
620 static enum drbd_state_rv
621 drbd_req_state(struct drbd_conf *mdev, union drbd_state mask,
622 union drbd_state val, enum chg_state_flags f)
624 struct completion done;
626 union drbd_state os, ns;
627 enum drbd_state_rv rv;
629 init_completion(&done);
631 if (f & CS_SERIALIZE)
632 mutex_lock(&mdev->state_mutex);
634 spin_lock_irqsave(&mdev->req_lock, flags);
636 ns.i = (os.i & ~mask.i) | val.i;
637 ns = sanitize_state(mdev, os, ns, NULL);
639 if (cl_wide_st_chg(mdev, os, ns)) {
640 rv = is_valid_state(mdev, ns);
641 if (rv == SS_SUCCESS)
642 rv = is_valid_state_transition(mdev, ns, os);
643 spin_unlock_irqrestore(&mdev->req_lock, flags);
645 if (rv < SS_SUCCESS) {
647 print_st_err(mdev, os, ns, rv);
651 drbd_state_lock(mdev);
652 if (!drbd_send_state_req(mdev, mask, val)) {
653 drbd_state_unlock(mdev);
654 rv = SS_CW_FAILED_BY_PEER;
656 print_st_err(mdev, os, ns, rv);
660 wait_event(mdev->state_wait,
661 (rv = _req_st_cond(mdev, mask, val)));
663 if (rv < SS_SUCCESS) {
664 drbd_state_unlock(mdev);
666 print_st_err(mdev, os, ns, rv);
669 spin_lock_irqsave(&mdev->req_lock, flags);
671 ns.i = (os.i & ~mask.i) | val.i;
672 rv = _drbd_set_state(mdev, ns, f, &done);
673 drbd_state_unlock(mdev);
675 rv = _drbd_set_state(mdev, ns, f, &done);
678 spin_unlock_irqrestore(&mdev->req_lock, flags);
680 if (f & CS_WAIT_COMPLETE && rv == SS_SUCCESS) {
681 D_ASSERT(current != mdev->worker.task);
682 wait_for_completion(&done);
686 if (f & CS_SERIALIZE)
687 mutex_unlock(&mdev->state_mutex);
693 * _drbd_request_state() - Request a state change (with flags)
694 * @mdev: DRBD device.
695 * @mask: mask of state bits to change.
696 * @val: value of new state bits.
699 * Cousin of drbd_request_state(), useful with the CS_WAIT_COMPLETE
700 * flag, or when logging of failed state change requests is not desired.
703 _drbd_request_state(struct drbd_conf *mdev, union drbd_state mask,
704 union drbd_state val, enum chg_state_flags f)
706 enum drbd_state_rv rv;
708 wait_event(mdev->state_wait,
709 (rv = drbd_req_state(mdev, mask, val, f)) != SS_IN_TRANSIENT_STATE);
714 static void print_st(struct drbd_conf *mdev, char *name, union drbd_state ns)
716 dev_err(DEV, " %s = { cs:%s ro:%s/%s ds:%s/%s %c%c%c%c }\n",
718 drbd_conn_str(ns.conn),
719 drbd_role_str(ns.role),
720 drbd_role_str(ns.peer),
721 drbd_disk_str(ns.disk),
722 drbd_disk_str(ns.pdsk),
723 is_susp(ns) ? 's' : 'r',
724 ns.aftr_isp ? 'a' : '-',
725 ns.peer_isp ? 'p' : '-',
726 ns.user_isp ? 'u' : '-'
730 void print_st_err(struct drbd_conf *mdev, union drbd_state os,
731 union drbd_state ns, enum drbd_state_rv err)
733 if (err == SS_IN_TRANSIENT_STATE)
735 dev_err(DEV, "State change failed: %s\n", drbd_set_st_err_str(err));
736 print_st(mdev, " state", os);
737 print_st(mdev, "wanted", ns);
742 * is_valid_state() - Returns an SS_ error code if ns is not valid
743 * @mdev: DRBD device.
744 * @ns: State to consider.
746 static enum drbd_state_rv
747 is_valid_state(struct drbd_conf *mdev, union drbd_state ns)
749 /* See drbd_state_sw_errors in drbd_strings.c */
751 enum drbd_fencing_p fp;
752 enum drbd_state_rv rv = SS_SUCCESS;
755 if (get_ldev(mdev)) {
756 fp = mdev->ldev->dc.fencing;
760 if (get_net_conf(mdev)) {
761 if (!mdev->net_conf->two_primaries &&
762 ns.role == R_PRIMARY && ns.peer == R_PRIMARY)
763 rv = SS_TWO_PRIMARIES;
768 /* already found a reason to abort */;
769 else if (ns.role == R_SECONDARY && mdev->open_cnt)
770 rv = SS_DEVICE_IN_USE;
772 else if (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.disk < D_UP_TO_DATE)
773 rv = SS_NO_UP_TO_DATE_DISK;
775 else if (fp >= FP_RESOURCE &&
776 ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk >= D_UNKNOWN)
779 else if (ns.role == R_PRIMARY && ns.disk <= D_INCONSISTENT && ns.pdsk <= D_INCONSISTENT)
780 rv = SS_NO_UP_TO_DATE_DISK;
782 else if (ns.conn > C_CONNECTED && ns.disk < D_INCONSISTENT)
783 rv = SS_NO_LOCAL_DISK;
785 else if (ns.conn > C_CONNECTED && ns.pdsk < D_INCONSISTENT)
786 rv = SS_NO_REMOTE_DISK;
788 else if (ns.conn > C_CONNECTED && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE)
789 rv = SS_NO_UP_TO_DATE_DISK;
791 else if ((ns.conn == C_CONNECTED ||
792 ns.conn == C_WF_BITMAP_S ||
793 ns.conn == C_SYNC_SOURCE ||
794 ns.conn == C_PAUSED_SYNC_S) &&
795 ns.disk == D_OUTDATED)
796 rv = SS_CONNECTED_OUTDATES;
798 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
799 (mdev->sync_conf.verify_alg[0] == 0))
800 rv = SS_NO_VERIFY_ALG;
802 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
803 mdev->agreed_pro_version < 88)
804 rv = SS_NOT_SUPPORTED;
806 else if (ns.conn >= C_CONNECTED && ns.pdsk == D_UNKNOWN)
807 rv = SS_CONNECTED_OUTDATES;
813 * is_valid_state_transition() - Returns an SS_ error code if the state transition is not possible
814 * @mdev: DRBD device.
818 static enum drbd_state_rv
819 is_valid_state_transition(struct drbd_conf *mdev, union drbd_state ns,
822 enum drbd_state_rv rv = SS_SUCCESS;
824 if ((ns.conn == C_STARTING_SYNC_T || ns.conn == C_STARTING_SYNC_S) &&
825 os.conn > C_CONNECTED)
826 rv = SS_RESYNC_RUNNING;
828 if (ns.conn == C_DISCONNECTING && os.conn == C_STANDALONE)
829 rv = SS_ALREADY_STANDALONE;
831 if (ns.disk > D_ATTACHING && os.disk == D_DISKLESS)
834 if (ns.conn == C_WF_CONNECTION && os.conn < C_UNCONNECTED)
835 rv = SS_NO_NET_CONFIG;
837 if (ns.disk == D_OUTDATED && os.disk < D_OUTDATED && os.disk != D_ATTACHING)
838 rv = SS_LOWER_THAN_OUTDATED;
840 if (ns.conn == C_DISCONNECTING && os.conn == C_UNCONNECTED)
841 rv = SS_IN_TRANSIENT_STATE;
843 if (ns.conn == os.conn && ns.conn == C_WF_REPORT_PARAMS)
844 rv = SS_IN_TRANSIENT_STATE;
846 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && os.conn < C_CONNECTED)
847 rv = SS_NEED_CONNECTION;
849 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
850 ns.conn != os.conn && os.conn > C_CONNECTED)
851 rv = SS_RESYNC_RUNNING;
853 if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) &&
854 os.conn < C_CONNECTED)
855 rv = SS_NEED_CONNECTION;
857 if ((ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)
858 && os.conn < C_WF_REPORT_PARAMS)
859 rv = SS_NEED_CONNECTION; /* No NetworkFailure -> SyncTarget etc... */
864 static void print_sanitize_warnings(struct drbd_conf *mdev, enum sanitize_state_warnings warn)
866 static const char *msg_table[] = {
868 [ABORTED_ONLINE_VERIFY] = "Online-verify aborted.",
869 [ABORTED_RESYNC] = "Resync aborted.",
870 [CONNECTION_LOST_NEGOTIATING] = "Connection lost while negotiating, no data!",
871 [IMPLICITLY_UPGRADED_DISK] = "Implicitly upgraded disk",
872 [IMPLICITLY_UPGRADED_PDSK] = "Implicitly upgraded pdsk",
875 if (warn != NO_WARNING)
876 dev_warn(DEV, "%s\n", msg_table[warn]);
880 * sanitize_state() - Resolves implicitly necessary additional changes to a state transition
881 * @mdev: DRBD device.
886 * When we loose connection, we have to set the state of the peers disk (pdsk)
887 * to D_UNKNOWN. This rule and many more along those lines are in this function.
889 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
890 union drbd_state ns, enum sanitize_state_warnings *warn)
892 enum drbd_fencing_p fp;
893 enum drbd_disk_state disk_min, disk_max, pdsk_min, pdsk_max;
899 if (get_ldev(mdev)) {
900 fp = mdev->ldev->dc.fencing;
904 /* Disallow Network errors to configure a device's network part */
905 if ((ns.conn >= C_TIMEOUT && ns.conn <= C_TEAR_DOWN) &&
906 os.conn <= C_DISCONNECTING)
909 /* After a network error (+C_TEAR_DOWN) only C_UNCONNECTED or C_DISCONNECTING can follow.
910 * If you try to go into some Sync* state, that shall fail (elsewhere). */
911 if (os.conn >= C_TIMEOUT && os.conn <= C_TEAR_DOWN &&
912 ns.conn != C_UNCONNECTED && ns.conn != C_DISCONNECTING && ns.conn <= C_TEAR_DOWN)
915 /* we cannot fail (again) if we already detached */
916 if (ns.disk == D_FAILED && os.disk == D_DISKLESS)
917 ns.disk = D_DISKLESS;
919 /* if we are only D_ATTACHING yet,
920 * we can (and should) go directly to D_DISKLESS. */
921 if (ns.disk == D_FAILED && os.disk == D_ATTACHING)
922 ns.disk = D_DISKLESS;
924 /* After C_DISCONNECTING only C_STANDALONE may follow */
925 if (os.conn == C_DISCONNECTING && ns.conn != C_STANDALONE)
928 if (ns.conn < C_CONNECTED) {
931 if (ns.pdsk > D_UNKNOWN || ns.pdsk < D_INCONSISTENT)
935 /* Clear the aftr_isp when becoming unconfigured */
936 if (ns.conn == C_STANDALONE && ns.disk == D_DISKLESS && ns.role == R_SECONDARY)
939 /* Abort resync if a disk fails/detaches */
940 if (os.conn > C_CONNECTED && ns.conn > C_CONNECTED &&
941 (ns.disk <= D_FAILED || ns.pdsk <= D_FAILED)) {
943 *warn = os.conn == C_VERIFY_S || os.conn == C_VERIFY_T ?
944 ABORTED_ONLINE_VERIFY : ABORTED_RESYNC;
945 ns.conn = C_CONNECTED;
948 /* Connection breaks down before we finished "Negotiating" */
949 if (ns.conn < C_CONNECTED && ns.disk == D_NEGOTIATING &&
950 get_ldev_if_state(mdev, D_NEGOTIATING)) {
951 if (mdev->ed_uuid == mdev->ldev->md.uuid[UI_CURRENT]) {
952 ns.disk = mdev->new_state_tmp.disk;
953 ns.pdsk = mdev->new_state_tmp.pdsk;
956 *warn = CONNECTION_LOST_NEGOTIATING;
957 ns.disk = D_DISKLESS;
963 /* D_CONSISTENT and D_OUTDATED vanish when we get connected */
964 if (ns.conn >= C_CONNECTED && ns.conn < C_AHEAD) {
965 if (ns.disk == D_CONSISTENT || ns.disk == D_OUTDATED)
966 ns.disk = D_UP_TO_DATE;
967 if (ns.pdsk == D_CONSISTENT || ns.pdsk == D_OUTDATED)
968 ns.pdsk = D_UP_TO_DATE;
971 /* Implications of the connection stat on the disk states */
972 disk_min = D_DISKLESS;
973 disk_max = D_UP_TO_DATE;
974 pdsk_min = D_INCONSISTENT;
975 pdsk_max = D_UNKNOWN;
976 switch ((enum drbd_conns)ns.conn) {
978 case C_PAUSED_SYNC_T:
979 case C_STARTING_SYNC_T:
982 disk_min = D_INCONSISTENT;
983 disk_max = D_OUTDATED;
984 pdsk_min = D_UP_TO_DATE;
985 pdsk_max = D_UP_TO_DATE;
989 disk_min = D_UP_TO_DATE;
990 disk_max = D_UP_TO_DATE;
991 pdsk_min = D_UP_TO_DATE;
992 pdsk_max = D_UP_TO_DATE;
995 disk_min = D_DISKLESS;
996 disk_max = D_UP_TO_DATE;
997 pdsk_min = D_DISKLESS;
998 pdsk_max = D_UP_TO_DATE;
1001 case C_PAUSED_SYNC_S:
1002 case C_STARTING_SYNC_S:
1004 disk_min = D_UP_TO_DATE;
1005 disk_max = D_UP_TO_DATE;
1006 pdsk_min = D_INCONSISTENT;
1007 pdsk_max = D_CONSISTENT; /* D_OUTDATED would be nice. But explicit outdate necessary*/
1010 disk_min = D_INCONSISTENT;
1011 disk_max = D_INCONSISTENT;
1012 pdsk_min = D_UP_TO_DATE;
1013 pdsk_max = D_UP_TO_DATE;
1016 disk_min = D_UP_TO_DATE;
1017 disk_max = D_UP_TO_DATE;
1018 pdsk_min = D_INCONSISTENT;
1019 pdsk_max = D_INCONSISTENT;
1022 case C_DISCONNECTING:
1026 case C_NETWORK_FAILURE:
1027 case C_PROTOCOL_ERROR:
1029 case C_WF_CONNECTION:
1030 case C_WF_REPORT_PARAMS:
1034 if (ns.disk > disk_max)
1037 if (ns.disk < disk_min) {
1039 *warn = IMPLICITLY_UPGRADED_DISK;
1042 if (ns.pdsk > pdsk_max)
1045 if (ns.pdsk < pdsk_min) {
1047 *warn = IMPLICITLY_UPGRADED_PDSK;
1051 if (fp == FP_STONITH &&
1052 (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk > D_OUTDATED) &&
1053 !(os.role == R_PRIMARY && os.conn < C_CONNECTED && os.pdsk > D_OUTDATED))
1054 ns.susp_fen = 1; /* Suspend IO while fence-peer handler runs (peer lost) */
1056 if (mdev->sync_conf.on_no_data == OND_SUSPEND_IO &&
1057 (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE) &&
1058 !(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE))
1059 ns.susp_nod = 1; /* Suspend IO while no data available (no accessible data available) */
1061 if (ns.aftr_isp || ns.peer_isp || ns.user_isp) {
1062 if (ns.conn == C_SYNC_SOURCE)
1063 ns.conn = C_PAUSED_SYNC_S;
1064 if (ns.conn == C_SYNC_TARGET)
1065 ns.conn = C_PAUSED_SYNC_T;
1067 if (ns.conn == C_PAUSED_SYNC_S)
1068 ns.conn = C_SYNC_SOURCE;
1069 if (ns.conn == C_PAUSED_SYNC_T)
1070 ns.conn = C_SYNC_TARGET;
1076 /* helper for __drbd_set_state */
1077 static void set_ov_position(struct drbd_conf *mdev, enum drbd_conns cs)
1079 if (mdev->agreed_pro_version < 90)
1080 mdev->ov_start_sector = 0;
1081 mdev->rs_total = drbd_bm_bits(mdev);
1082 mdev->ov_position = 0;
1083 if (cs == C_VERIFY_T) {
1084 /* starting online verify from an arbitrary position
1085 * does not fit well into the existing protocol.
1086 * on C_VERIFY_T, we initialize ov_left and friends
1087 * implicitly in receive_DataRequest once the
1088 * first P_OV_REQUEST is received */
1089 mdev->ov_start_sector = ~(sector_t)0;
1091 unsigned long bit = BM_SECT_TO_BIT(mdev->ov_start_sector);
1092 if (bit >= mdev->rs_total) {
1093 mdev->ov_start_sector =
1094 BM_BIT_TO_SECT(mdev->rs_total - 1);
1097 mdev->rs_total -= bit;
1098 mdev->ov_position = mdev->ov_start_sector;
1100 mdev->ov_left = mdev->rs_total;
1103 static void drbd_resume_al(struct drbd_conf *mdev)
1105 if (test_and_clear_bit(AL_SUSPENDED, &mdev->flags))
1106 dev_info(DEV, "Resumed AL updates\n");
1110 * __drbd_set_state() - Set a new DRBD state
1111 * @mdev: DRBD device.
1114 * @done: Optional completion, that will get completed after the after_state_ch() finished
1116 * Caller needs to hold req_lock, and global_state_lock. Do not call directly.
1119 __drbd_set_state(struct drbd_conf *mdev, union drbd_state ns,
1120 enum chg_state_flags flags, struct completion *done)
1122 union drbd_state os;
1123 enum drbd_state_rv rv = SS_SUCCESS;
1124 enum sanitize_state_warnings ssw;
1125 struct after_state_chg_work *ascw;
1129 ns = sanitize_state(mdev, os, ns, &ssw);
1132 return SS_NOTHING_TO_DO;
1134 if (!(flags & CS_HARD)) {
1135 /* pre-state-change checks ; only look at ns */
1136 /* See drbd_state_sw_errors in drbd_strings.c */
1138 rv = is_valid_state(mdev, ns);
1139 if (rv < SS_SUCCESS) {
1140 /* If the old state was illegal as well, then let
1143 if (is_valid_state(mdev, os) == rv)
1144 rv = is_valid_state_transition(mdev, ns, os);
1146 rv = is_valid_state_transition(mdev, ns, os);
1149 if (rv < SS_SUCCESS) {
1150 if (flags & CS_VERBOSE)
1151 print_st_err(mdev, os, ns, rv);
1155 print_sanitize_warnings(mdev, ssw);
1161 if (ns.role != os.role)
1162 pbp += sprintf(pbp, "role( %s -> %s ) ",
1163 drbd_role_str(os.role),
1164 drbd_role_str(ns.role));
1165 if (ns.peer != os.peer)
1166 pbp += sprintf(pbp, "peer( %s -> %s ) ",
1167 drbd_role_str(os.peer),
1168 drbd_role_str(ns.peer));
1169 if (ns.conn != os.conn)
1170 pbp += sprintf(pbp, "conn( %s -> %s ) ",
1171 drbd_conn_str(os.conn),
1172 drbd_conn_str(ns.conn));
1173 if (ns.disk != os.disk)
1174 pbp += sprintf(pbp, "disk( %s -> %s ) ",
1175 drbd_disk_str(os.disk),
1176 drbd_disk_str(ns.disk));
1177 if (ns.pdsk != os.pdsk)
1178 pbp += sprintf(pbp, "pdsk( %s -> %s ) ",
1179 drbd_disk_str(os.pdsk),
1180 drbd_disk_str(ns.pdsk));
1181 if (is_susp(ns) != is_susp(os))
1182 pbp += sprintf(pbp, "susp( %d -> %d ) ",
1185 if (ns.aftr_isp != os.aftr_isp)
1186 pbp += sprintf(pbp, "aftr_isp( %d -> %d ) ",
1189 if (ns.peer_isp != os.peer_isp)
1190 pbp += sprintf(pbp, "peer_isp( %d -> %d ) ",
1193 if (ns.user_isp != os.user_isp)
1194 pbp += sprintf(pbp, "user_isp( %d -> %d ) ",
1197 dev_info(DEV, "%s\n", pb);
1200 /* solve the race between becoming unconfigured,
1201 * worker doing the cleanup, and
1202 * admin reconfiguring us:
1203 * on (re)configure, first set CONFIG_PENDING,
1204 * then wait for a potentially exiting worker,
1205 * start the worker, and schedule one no_op.
1206 * then proceed with configuration.
1208 if (ns.disk == D_DISKLESS &&
1209 ns.conn == C_STANDALONE &&
1210 ns.role == R_SECONDARY &&
1211 !test_and_set_bit(CONFIG_PENDING, &mdev->flags))
1212 set_bit(DEVICE_DYING, &mdev->flags);
1214 /* if we are going -> D_FAILED or D_DISKLESS, grab one extra reference
1215 * on the ldev here, to be sure the transition -> D_DISKLESS resp.
1216 * drbd_ldev_destroy() won't happen before our corresponding
1217 * after_state_ch works run, where we put_ldev again. */
1218 if ((os.disk != D_FAILED && ns.disk == D_FAILED) ||
1219 (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))
1220 atomic_inc(&mdev->local_cnt);
1224 if (os.disk == D_ATTACHING && ns.disk >= D_NEGOTIATING)
1225 drbd_print_uuids(mdev, "attached to UUIDs");
1227 wake_up(&mdev->misc_wait);
1228 wake_up(&mdev->state_wait);
1230 /* aborted verify run. log the last position */
1231 if ((os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) &&
1232 ns.conn < C_CONNECTED) {
1233 mdev->ov_start_sector =
1234 BM_BIT_TO_SECT(drbd_bm_bits(mdev) - mdev->ov_left);
1235 dev_info(DEV, "Online Verify reached sector %llu\n",
1236 (unsigned long long)mdev->ov_start_sector);
1239 if ((os.conn == C_PAUSED_SYNC_T || os.conn == C_PAUSED_SYNC_S) &&
1240 (ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)) {
1241 dev_info(DEV, "Syncer continues.\n");
1242 mdev->rs_paused += (long)jiffies
1243 -(long)mdev->rs_mark_time[mdev->rs_last_mark];
1244 if (ns.conn == C_SYNC_TARGET)
1245 mod_timer(&mdev->resync_timer, jiffies);
1248 if ((os.conn == C_SYNC_TARGET || os.conn == C_SYNC_SOURCE) &&
1249 (ns.conn == C_PAUSED_SYNC_T || ns.conn == C_PAUSED_SYNC_S)) {
1250 dev_info(DEV, "Resync suspended\n");
1251 mdev->rs_mark_time[mdev->rs_last_mark] = jiffies;
1254 if (os.conn == C_CONNECTED &&
1255 (ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T)) {
1256 unsigned long now = jiffies;
1259 set_ov_position(mdev, ns.conn);
1260 mdev->rs_start = now;
1261 mdev->rs_last_events = 0;
1262 mdev->rs_last_sect_ev = 0;
1263 mdev->ov_last_oos_size = 0;
1264 mdev->ov_last_oos_start = 0;
1266 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
1267 mdev->rs_mark_left[i] = mdev->ov_left;
1268 mdev->rs_mark_time[i] = now;
1271 drbd_rs_controller_reset(mdev);
1273 if (ns.conn == C_VERIFY_S) {
1274 dev_info(DEV, "Starting Online Verify from sector %llu\n",
1275 (unsigned long long)mdev->ov_position);
1276 mod_timer(&mdev->resync_timer, jiffies);
1280 if (get_ldev(mdev)) {
1281 u32 mdf = mdev->ldev->md.flags & ~(MDF_CONSISTENT|MDF_PRIMARY_IND|
1282 MDF_CONNECTED_IND|MDF_WAS_UP_TO_DATE|
1283 MDF_PEER_OUT_DATED|MDF_CRASHED_PRIMARY);
1285 if (test_bit(CRASHED_PRIMARY, &mdev->flags))
1286 mdf |= MDF_CRASHED_PRIMARY;
1287 if (mdev->state.role == R_PRIMARY ||
1288 (mdev->state.pdsk < D_INCONSISTENT && mdev->state.peer == R_PRIMARY))
1289 mdf |= MDF_PRIMARY_IND;
1290 if (mdev->state.conn > C_WF_REPORT_PARAMS)
1291 mdf |= MDF_CONNECTED_IND;
1292 if (mdev->state.disk > D_INCONSISTENT)
1293 mdf |= MDF_CONSISTENT;
1294 if (mdev->state.disk > D_OUTDATED)
1295 mdf |= MDF_WAS_UP_TO_DATE;
1296 if (mdev->state.pdsk <= D_OUTDATED && mdev->state.pdsk >= D_INCONSISTENT)
1297 mdf |= MDF_PEER_OUT_DATED;
1298 if (mdf != mdev->ldev->md.flags) {
1299 mdev->ldev->md.flags = mdf;
1300 drbd_md_mark_dirty(mdev);
1302 if (os.disk < D_CONSISTENT && ns.disk >= D_CONSISTENT)
1303 drbd_set_ed_uuid(mdev, mdev->ldev->md.uuid[UI_CURRENT]);
1307 /* Peer was forced D_UP_TO_DATE & R_PRIMARY, consider to resync */
1308 if (os.disk == D_INCONSISTENT && os.pdsk == D_INCONSISTENT &&
1309 os.peer == R_SECONDARY && ns.peer == R_PRIMARY)
1310 set_bit(CONSIDER_RESYNC, &mdev->flags);
1312 /* Receiver should clean up itself */
1313 if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING)
1314 drbd_thread_stop_nowait(&mdev->receiver);
1316 /* Now the receiver finished cleaning up itself, it should die */
1317 if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE)
1318 drbd_thread_stop_nowait(&mdev->receiver);
1320 /* Upon network failure, we need to restart the receiver. */
1321 if (os.conn > C_WF_CONNECTION &&
1322 ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT)
1323 drbd_thread_restart_nowait(&mdev->receiver);
1325 /* Resume AL writing if we get a connection */
1326 if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)
1327 drbd_resume_al(mdev);
1329 ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC);
1333 ascw->flags = flags;
1334 ascw->w.cb = w_after_state_ch;
1336 drbd_queue_work(&mdev->data.work, &ascw->w);
1338 dev_warn(DEV, "Could not kmalloc an ascw\n");
1344 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused)
1346 struct after_state_chg_work *ascw =
1347 container_of(w, struct after_state_chg_work, w);
1348 after_state_ch(mdev, ascw->os, ascw->ns, ascw->flags);
1349 if (ascw->flags & CS_WAIT_COMPLETE) {
1350 D_ASSERT(ascw->done != NULL);
1351 complete(ascw->done);
1358 static void abw_start_sync(struct drbd_conf *mdev, int rv)
1361 dev_err(DEV, "Writing the bitmap failed not starting resync.\n");
1362 _drbd_request_state(mdev, NS(conn, C_CONNECTED), CS_VERBOSE);
1366 switch (mdev->state.conn) {
1367 case C_STARTING_SYNC_T:
1368 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE);
1370 case C_STARTING_SYNC_S:
1371 drbd_start_resync(mdev, C_SYNC_SOURCE);
1376 int drbd_bitmap_io_from_worker(struct drbd_conf *mdev,
1377 int (*io_fn)(struct drbd_conf *),
1378 char *why, enum bm_flag flags)
1382 D_ASSERT(current == mdev->worker.task);
1384 /* open coded non-blocking drbd_suspend_io(mdev); */
1385 set_bit(SUSPEND_IO, &mdev->flags);
1387 drbd_bm_lock(mdev, why, flags);
1389 drbd_bm_unlock(mdev);
1391 drbd_resume_io(mdev);
1397 * after_state_ch() - Perform after state change actions that may sleep
1398 * @mdev: DRBD device.
1403 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
1404 union drbd_state ns, enum chg_state_flags flags)
1406 enum drbd_fencing_p fp;
1407 enum drbd_req_event what = nothing;
1408 union drbd_state nsm = (union drbd_state){ .i = -1 };
1410 if (os.conn != C_CONNECTED && ns.conn == C_CONNECTED) {
1411 clear_bit(CRASHED_PRIMARY, &mdev->flags);
1413 mdev->p_uuid[UI_FLAGS] &= ~((u64)2);
1417 if (get_ldev(mdev)) {
1418 fp = mdev->ldev->dc.fencing;
1422 /* Inform userspace about the change... */
1423 drbd_bcast_state(mdev, ns);
1425 if (!(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE) &&
1426 (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE))
1427 drbd_khelper(mdev, "pri-on-incon-degr");
1429 /* Here we have the actions that are performed after a
1430 state change. This function might sleep */
1432 if (os.disk <= D_NEGOTIATING && ns.disk > D_NEGOTIATING)
1433 mod_timer(&mdev->request_timer, jiffies + HZ);
1437 if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)
1440 if ((os.disk == D_ATTACHING || os.disk == D_NEGOTIATING) &&
1441 ns.disk > D_NEGOTIATING)
1442 what = restart_frozen_disk_io;
1444 if (what != nothing)
1449 /* case1: The outdate peer handler is successful: */
1450 if (os.pdsk > D_OUTDATED && ns.pdsk <= D_OUTDATED) {
1452 if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
1453 drbd_uuid_new_current(mdev);
1454 clear_bit(NEW_CUR_UUID, &mdev->flags);
1456 spin_lock_irq(&mdev->req_lock);
1457 _drbd_set_state(_NS(mdev, susp_fen, 0), CS_VERBOSE, NULL);
1458 spin_unlock_irq(&mdev->req_lock);
1460 /* case2: The connection was established again: */
1461 if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED) {
1462 clear_bit(NEW_CUR_UUID, &mdev->flags);
1468 if (what != nothing) {
1469 spin_lock_irq(&mdev->req_lock);
1470 _tl_restart(mdev, what);
1471 nsm.i &= mdev->state.i;
1472 _drbd_set_state(mdev, nsm, CS_VERBOSE, NULL);
1473 spin_unlock_irq(&mdev->req_lock);
1476 /* Became sync source. With protocol >= 96, we still need to send out
1477 * the sync uuid now. Need to do that before any drbd_send_state, or
1478 * the other side may go "paused sync" before receiving the sync uuids,
1479 * which is unexpected. */
1480 if ((os.conn != C_SYNC_SOURCE && os.conn != C_PAUSED_SYNC_S) &&
1481 (ns.conn == C_SYNC_SOURCE || ns.conn == C_PAUSED_SYNC_S) &&
1482 mdev->agreed_pro_version >= 96 && get_ldev(mdev)) {
1483 drbd_gen_and_send_sync_uuid(mdev);
1487 /* Do not change the order of the if above and the two below... */
1488 if (os.pdsk == D_DISKLESS && ns.pdsk > D_DISKLESS) { /* attach on the peer */
1489 drbd_send_uuids(mdev);
1490 drbd_send_state(mdev, ns);
1492 /* No point in queuing send_bitmap if we don't have a connection
1493 * anymore, so check also the _current_ state, not only the new state
1494 * at the time this work was queued. */
1495 if (os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S &&
1496 mdev->state.conn == C_WF_BITMAP_S)
1497 drbd_queue_bitmap_io(mdev, &drbd_send_bitmap, NULL,
1498 "send_bitmap (WFBitMapS)",
1499 BM_LOCKED_TEST_ALLOWED);
1501 /* Lost contact to peer's copy of the data */
1502 if ((os.pdsk >= D_INCONSISTENT &&
1503 os.pdsk != D_UNKNOWN &&
1504 os.pdsk != D_OUTDATED)
1505 && (ns.pdsk < D_INCONSISTENT ||
1506 ns.pdsk == D_UNKNOWN ||
1507 ns.pdsk == D_OUTDATED)) {
1508 if (get_ldev(mdev)) {
1509 if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) &&
1510 mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) {
1511 if (is_susp(mdev->state)) {
1512 set_bit(NEW_CUR_UUID, &mdev->flags);
1514 drbd_uuid_new_current(mdev);
1515 drbd_send_uuids(mdev);
1522 if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) {
1523 if (os.peer == R_SECONDARY && ns.peer == R_PRIMARY &&
1524 mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) {
1525 drbd_uuid_new_current(mdev);
1526 drbd_send_uuids(mdev);
1528 /* D_DISKLESS Peer becomes secondary */
1529 if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
1530 /* We may still be Primary ourselves.
1531 * No harm done if the bitmap still changes,
1532 * redirtied pages will follow later. */
1533 drbd_bitmap_io_from_worker(mdev, &drbd_bm_write,
1534 "demote diskless peer", BM_LOCKED_SET_ALLOWED);
1538 /* Write out all changed bits on demote.
1539 * Though, no need to da that just yet
1540 * if there is a resync going on still */
1541 if (os.role == R_PRIMARY && ns.role == R_SECONDARY &&
1542 mdev->state.conn <= C_CONNECTED && get_ldev(mdev)) {
1543 /* No changes to the bitmap expected this time, so assert that,
1544 * even though no harm was done if it did change. */
1545 drbd_bitmap_io_from_worker(mdev, &drbd_bm_write,
1546 "demote", BM_LOCKED_TEST_ALLOWED);
1550 /* Last part of the attaching process ... */
1551 if (ns.conn >= C_CONNECTED &&
1552 os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
1553 drbd_send_sizes(mdev, 0, 0); /* to start sync... */
1554 drbd_send_uuids(mdev);
1555 drbd_send_state(mdev, ns);
1558 /* We want to pause/continue resync, tell peer. */
1559 if (ns.conn >= C_CONNECTED &&
1560 ((os.aftr_isp != ns.aftr_isp) ||
1561 (os.user_isp != ns.user_isp)))
1562 drbd_send_state(mdev, ns);
1564 /* In case one of the isp bits got set, suspend other devices. */
1565 if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
1566 (ns.aftr_isp || ns.peer_isp || ns.user_isp))
1567 suspend_other_sg(mdev);
1569 /* Make sure the peer gets informed about eventual state
1570 changes (ISP bits) while we were in WFReportParams. */
1571 if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
1572 drbd_send_state(mdev, ns);
1574 if (os.conn != C_AHEAD && ns.conn == C_AHEAD)
1575 drbd_send_state(mdev, ns);
1577 /* We are in the progress to start a full sync... */
1578 if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
1579 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S))
1580 /* no other bitmap changes expected during this phase */
1581 drbd_queue_bitmap_io(mdev,
1582 &drbd_bmio_set_n_write, &abw_start_sync,
1583 "set_n_write from StartingSync", BM_LOCKED_TEST_ALLOWED);
1585 /* We are invalidating our self... */
1586 if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED &&
1587 os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT)
1588 /* other bitmap operation expected during this phase */
1589 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL,
1590 "set_n_write from invalidate", BM_LOCKED_MASK);
1592 /* first half of local IO error, failure to attach,
1593 * or administrative detach */
1594 if (os.disk != D_FAILED && ns.disk == D_FAILED) {
1595 enum drbd_io_error_p eh;
1597 /* corresponding get_ldev was in __drbd_set_state, to serialize
1598 * our cleanup here with the transition to D_DISKLESS,
1599 * so it is safe to dreference ldev here. */
1600 eh = mdev->ldev->dc.on_io_error;
1601 was_io_error = test_and_clear_bit(WAS_IO_ERROR, &mdev->flags);
1603 /* Immediately allow completion of all application IO, that waits
1604 for completion from the local disk. */
1605 tl_abort_disk_io(mdev);
1607 /* current state still has to be D_FAILED,
1608 * there is only one way out: to D_DISKLESS,
1609 * and that may only happen after our put_ldev below. */
1610 if (mdev->state.disk != D_FAILED)
1612 "ASSERT FAILED: disk is %s during detach\n",
1613 drbd_disk_str(mdev->state.disk));
1615 if (drbd_send_state(mdev, ns))
1616 dev_info(DEV, "Notified peer that I am detaching my disk\n");
1618 drbd_rs_cancel_all(mdev);
1620 /* In case we want to get something to stable storage still,
1621 * this may be the last chance.
1622 * Following put_ldev may transition to D_DISKLESS. */
1626 if (was_io_error && eh == EP_CALL_HELPER)
1627 drbd_khelper(mdev, "local-io-error");
1630 /* second half of local IO error, failure to attach,
1631 * or administrative detach,
1632 * after local_cnt references have reached zero again */
1633 if (os.disk != D_DISKLESS && ns.disk == D_DISKLESS) {
1634 /* We must still be diskless,
1635 * re-attach has to be serialized with this! */
1636 if (mdev->state.disk != D_DISKLESS)
1638 "ASSERT FAILED: disk is %s while going diskless\n",
1639 drbd_disk_str(mdev->state.disk));
1642 mdev->rs_failed = 0;
1643 atomic_set(&mdev->rs_pending_cnt, 0);
1645 if (drbd_send_state(mdev, ns))
1646 dev_info(DEV, "Notified peer that I'm now diskless.\n");
1647 /* corresponding get_ldev in __drbd_set_state
1648 * this may finally trigger drbd_ldev_destroy. */
1652 /* Notify peer that I had a local IO error, and did not detached.. */
1653 if (os.disk == D_UP_TO_DATE && ns.disk == D_INCONSISTENT)
1654 drbd_send_state(mdev, ns);
1656 /* Disks got bigger while they were detached */
1657 if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
1658 test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) {
1659 if (ns.conn == C_CONNECTED)
1660 resync_after_online_grow(mdev);
1663 /* A resync finished or aborted, wake paused devices... */
1664 if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) ||
1665 (os.peer_isp && !ns.peer_isp) ||
1666 (os.user_isp && !ns.user_isp))
1667 resume_next_sg(mdev);
1669 /* sync target done with resync. Explicitly notify peer, even though
1670 * it should (at least for non-empty resyncs) already know itself. */
1671 if (os.disk < D_UP_TO_DATE && os.conn >= C_SYNC_SOURCE && ns.conn == C_CONNECTED)
1672 drbd_send_state(mdev, ns);
1674 /* This triggers bitmap writeout of potentially still unwritten pages
1675 * if the resync finished cleanly, or aborted because of peer disk
1676 * failure, or because of connection loss.
1677 * For resync aborted because of local disk failure, we cannot do
1678 * any bitmap writeout anymore.
1679 * No harm done if some bits change during this phase.
1681 if (os.conn > C_CONNECTED && ns.conn <= C_CONNECTED && get_ldev(mdev)) {
1682 drbd_queue_bitmap_io(mdev, &drbd_bm_write, NULL,
1683 "write from resync_finished", BM_LOCKED_SET_ALLOWED);
1687 /* free tl_hash if we Got thawed and are C_STANDALONE */
1688 if (ns.conn == C_STANDALONE && !is_susp(ns) && mdev->tl_hash)
1689 drbd_free_tl_hash(mdev);
1691 /* Upon network connection, we need to start the receiver */
1692 if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED)
1693 drbd_thread_start(&mdev->receiver);
1695 /* Terminate worker thread if we are unconfigured - it will be
1696 restarted as needed... */
1697 if (ns.disk == D_DISKLESS &&
1698 ns.conn == C_STANDALONE &&
1699 ns.role == R_SECONDARY) {
1700 if (os.aftr_isp != ns.aftr_isp)
1701 resume_next_sg(mdev);
1702 /* set in __drbd_set_state, unless CONFIG_PENDING was set */
1703 if (test_bit(DEVICE_DYING, &mdev->flags))
1704 drbd_thread_stop_nowait(&mdev->worker);
1711 static int drbd_thread_setup(void *arg)
1713 struct drbd_thread *thi = (struct drbd_thread *) arg;
1714 struct drbd_conf *mdev = thi->mdev;
1715 unsigned long flags;
1719 retval = thi->function(thi);
1721 spin_lock_irqsave(&thi->t_lock, flags);
1723 /* if the receiver has been "Exiting", the last thing it did
1724 * was set the conn state to "StandAlone",
1725 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
1726 * and receiver thread will be "started".
1727 * drbd_thread_start needs to set "Restarting" in that case.
1728 * t_state check and assignment needs to be within the same spinlock,
1729 * so either thread_start sees Exiting, and can remap to Restarting,
1730 * or thread_start see None, and can proceed as normal.
1733 if (thi->t_state == Restarting) {
1734 dev_info(DEV, "Restarting %s\n", current->comm);
1735 thi->t_state = Running;
1736 spin_unlock_irqrestore(&thi->t_lock, flags);
1741 thi->t_state = None;
1743 complete(&thi->stop);
1744 spin_unlock_irqrestore(&thi->t_lock, flags);
1746 dev_info(DEV, "Terminating %s\n", current->comm);
1748 /* Release mod reference taken when thread was started */
1749 module_put(THIS_MODULE);
1753 static void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi,
1754 int (*func) (struct drbd_thread *))
1756 spin_lock_init(&thi->t_lock);
1758 thi->t_state = None;
1759 thi->function = func;
1763 int drbd_thread_start(struct drbd_thread *thi)
1765 struct drbd_conf *mdev = thi->mdev;
1766 struct task_struct *nt;
1767 unsigned long flags;
1770 thi == &mdev->receiver ? "receiver" :
1771 thi == &mdev->asender ? "asender" :
1772 thi == &mdev->worker ? "worker" : "NONSENSE";
1774 /* is used from state engine doing drbd_thread_stop_nowait,
1775 * while holding the req lock irqsave */
1776 spin_lock_irqsave(&thi->t_lock, flags);
1778 switch (thi->t_state) {
1780 dev_info(DEV, "Starting %s thread (from %s [%d])\n",
1781 me, current->comm, current->pid);
1783 /* Get ref on module for thread - this is released when thread exits */
1784 if (!try_module_get(THIS_MODULE)) {
1785 dev_err(DEV, "Failed to get module reference in drbd_thread_start\n");
1786 spin_unlock_irqrestore(&thi->t_lock, flags);
1790 init_completion(&thi->stop);
1791 D_ASSERT(thi->task == NULL);
1792 thi->reset_cpu_mask = 1;
1793 thi->t_state = Running;
1794 spin_unlock_irqrestore(&thi->t_lock, flags);
1795 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
1797 nt = kthread_create(drbd_thread_setup, (void *) thi,
1798 "drbd%d_%s", mdev_to_minor(mdev), me);
1801 dev_err(DEV, "Couldn't start thread\n");
1803 module_put(THIS_MODULE);
1806 spin_lock_irqsave(&thi->t_lock, flags);
1808 thi->t_state = Running;
1809 spin_unlock_irqrestore(&thi->t_lock, flags);
1810 wake_up_process(nt);
1813 thi->t_state = Restarting;
1814 dev_info(DEV, "Restarting %s thread (from %s [%d])\n",
1815 me, current->comm, current->pid);
1820 spin_unlock_irqrestore(&thi->t_lock, flags);
1828 void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
1830 unsigned long flags;
1832 enum drbd_thread_state ns = restart ? Restarting : Exiting;
1834 /* may be called from state engine, holding the req lock irqsave */
1835 spin_lock_irqsave(&thi->t_lock, flags);
1837 if (thi->t_state == None) {
1838 spin_unlock_irqrestore(&thi->t_lock, flags);
1840 drbd_thread_start(thi);
1844 if (thi->t_state != ns) {
1845 if (thi->task == NULL) {
1846 spin_unlock_irqrestore(&thi->t_lock, flags);
1852 init_completion(&thi->stop);
1853 if (thi->task != current)
1854 force_sig(DRBD_SIGKILL, thi->task);
1858 spin_unlock_irqrestore(&thi->t_lock, flags);
1861 wait_for_completion(&thi->stop);
1866 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
1867 * @mdev: DRBD device.
1869 * Forces all threads of a device onto the same CPU. This is beneficial for
1870 * DRBD's performance. May be overwritten by user's configuration.
1872 void drbd_calc_cpu_mask(struct drbd_conf *mdev)
1876 /* user override. */
1877 if (cpumask_weight(mdev->cpu_mask))
1880 ord = mdev_to_minor(mdev) % cpumask_weight(cpu_online_mask);
1881 for_each_online_cpu(cpu) {
1883 cpumask_set_cpu(cpu, mdev->cpu_mask);
1887 /* should not be reached */
1888 cpumask_setall(mdev->cpu_mask);
1892 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
1893 * @mdev: DRBD device.
1895 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
1898 void drbd_thread_current_set_cpu(struct drbd_conf *mdev)
1900 struct task_struct *p = current;
1901 struct drbd_thread *thi =
1902 p == mdev->asender.task ? &mdev->asender :
1903 p == mdev->receiver.task ? &mdev->receiver :
1904 p == mdev->worker.task ? &mdev->worker :
1908 if (!thi->reset_cpu_mask)
1910 thi->reset_cpu_mask = 0;
1911 set_cpus_allowed_ptr(p, mdev->cpu_mask);
1915 /* the appropriate socket mutex must be held already */
1916 int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1917 enum drbd_packets cmd, struct p_header80 *h,
1918 size_t size, unsigned msg_flags)
1922 ERR_IF(!h) return false;
1923 ERR_IF(!size) return false;
1925 h->magic = BE_DRBD_MAGIC;
1926 h->command = cpu_to_be16(cmd);
1927 h->length = cpu_to_be16(size-sizeof(struct p_header80));
1929 sent = drbd_send(mdev, sock, h, size, msg_flags);
1931 ok = (sent == size);
1932 if (!ok && !signal_pending(current))
1933 dev_warn(DEV, "short sent %s size=%d sent=%d\n",
1934 cmdname(cmd), (int)size, sent);
1938 /* don't pass the socket. we may only look at it
1939 * when we hold the appropriate socket mutex.
1941 int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1942 enum drbd_packets cmd, struct p_header80 *h, size_t size)
1945 struct socket *sock;
1947 if (use_data_socket) {
1948 mutex_lock(&mdev->data.mutex);
1949 sock = mdev->data.socket;
1951 mutex_lock(&mdev->meta.mutex);
1952 sock = mdev->meta.socket;
1955 /* drbd_disconnect() could have called drbd_free_sock()
1956 * while we were waiting in down()... */
1957 if (likely(sock != NULL))
1958 ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0);
1960 if (use_data_socket)
1961 mutex_unlock(&mdev->data.mutex);
1963 mutex_unlock(&mdev->meta.mutex);
1967 int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
1970 struct p_header80 h;
1973 h.magic = BE_DRBD_MAGIC;
1974 h.command = cpu_to_be16(cmd);
1975 h.length = cpu_to_be16(size);
1977 if (!drbd_get_data_sock(mdev))
1981 drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0));
1983 drbd_send(mdev, mdev->data.socket, data, size, 0));
1985 drbd_put_data_sock(mdev);
1990 int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc)
1992 struct p_rs_param_95 *p;
1993 struct socket *sock;
1995 const int apv = mdev->agreed_pro_version;
1997 size = apv <= 87 ? sizeof(struct p_rs_param)
1998 : apv == 88 ? sizeof(struct p_rs_param)
1999 + strlen(mdev->sync_conf.verify_alg) + 1
2000 : apv <= 94 ? sizeof(struct p_rs_param_89)
2001 : /* apv >= 95 */ sizeof(struct p_rs_param_95);
2003 /* used from admin command context and receiver/worker context.
2004 * to avoid kmalloc, grab the socket right here,
2005 * then use the pre-allocated sbuf there */
2006 mutex_lock(&mdev->data.mutex);
2007 sock = mdev->data.socket;
2009 if (likely(sock != NULL)) {
2010 enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
2012 p = &mdev->data.sbuf.rs_param_95;
2014 /* initialize verify_alg and csums_alg */
2015 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
2017 p->rate = cpu_to_be32(sc->rate);
2018 p->c_plan_ahead = cpu_to_be32(sc->c_plan_ahead);
2019 p->c_delay_target = cpu_to_be32(sc->c_delay_target);
2020 p->c_fill_target = cpu_to_be32(sc->c_fill_target);
2021 p->c_max_rate = cpu_to_be32(sc->c_max_rate);
2024 strcpy(p->verify_alg, mdev->sync_conf.verify_alg);
2026 strcpy(p->csums_alg, mdev->sync_conf.csums_alg);
2028 rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
2030 rv = 0; /* not ok */
2032 mutex_unlock(&mdev->data.mutex);
2037 int drbd_send_protocol(struct drbd_conf *mdev)
2039 struct p_protocol *p;
2042 size = sizeof(struct p_protocol);
2044 if (mdev->agreed_pro_version >= 87)
2045 size += strlen(mdev->net_conf->integrity_alg) + 1;
2047 /* we must not recurse into our own queue,
2048 * as that is blocked during handshake */
2049 p = kmalloc(size, GFP_NOIO);
2053 p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol);
2054 p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p);
2055 p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p);
2056 p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p);
2057 p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries);
2060 if (mdev->net_conf->want_lose)
2062 if (mdev->net_conf->dry_run) {
2063 if (mdev->agreed_pro_version >= 92)
2066 dev_err(DEV, "--dry-run is not supported by peer");
2071 p->conn_flags = cpu_to_be32(cf);
2073 if (mdev->agreed_pro_version >= 87)
2074 strcpy(p->integrity_alg, mdev->net_conf->integrity_alg);
2076 rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL,
2077 (struct p_header80 *)p, size);
2082 int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
2087 if (!get_ldev_if_state(mdev, D_NEGOTIATING))
2090 for (i = UI_CURRENT; i < UI_SIZE; i++)
2091 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
2093 mdev->comm_bm_set = drbd_bm_total_weight(mdev);
2094 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
2095 uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
2096 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
2097 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
2098 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
2102 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS,
2103 (struct p_header80 *)&p, sizeof(p));
2106 int drbd_send_uuids(struct drbd_conf *mdev)
2108 return _drbd_send_uuids(mdev, 0);
2111 int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
2113 return _drbd_send_uuids(mdev, 8);
2116 void drbd_print_uuids(struct drbd_conf *mdev, const char *text)
2118 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
2119 u64 *uuid = mdev->ldev->md.uuid;
2120 dev_info(DEV, "%s %016llX:%016llX:%016llX:%016llX\n",
2122 (unsigned long long)uuid[UI_CURRENT],
2123 (unsigned long long)uuid[UI_BITMAP],
2124 (unsigned long long)uuid[UI_HISTORY_START],
2125 (unsigned long long)uuid[UI_HISTORY_END]);
2128 dev_info(DEV, "%s effective data uuid: %016llX\n",
2130 (unsigned long long)mdev->ed_uuid);
2134 int drbd_gen_and_send_sync_uuid(struct drbd_conf *mdev)
2139 D_ASSERT(mdev->state.disk == D_UP_TO_DATE);
2141 uuid = mdev->ldev->md.uuid[UI_BITMAP];
2142 if (uuid && uuid != UUID_JUST_CREATED)
2143 uuid = uuid + UUID_NEW_BM_OFFSET;
2145 get_random_bytes(&uuid, sizeof(u64));
2146 drbd_uuid_set(mdev, UI_BITMAP, uuid);
2147 drbd_print_uuids(mdev, "updated sync UUID");
2149 p.uuid = cpu_to_be64(uuid);
2151 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID,
2152 (struct p_header80 *)&p, sizeof(p));
2155 int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags)
2158 sector_t d_size, u_size;
2159 int q_order_type, max_bio_size;
2162 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
2163 D_ASSERT(mdev->ldev->backing_bdev);
2164 d_size = drbd_get_max_capacity(mdev->ldev);
2165 u_size = mdev->ldev->dc.disk_size;
2166 q_order_type = drbd_queue_order_type(mdev);
2167 max_bio_size = queue_max_hw_sectors(mdev->ldev->backing_bdev->bd_disk->queue) << 9;
2168 max_bio_size = min_t(int, max_bio_size, DRBD_MAX_BIO_SIZE);
2173 q_order_type = QUEUE_ORDERED_NONE;
2174 max_bio_size = DRBD_MAX_BIO_SIZE; /* ... multiple BIOs per peer_request */
2177 /* Never allow old drbd (up to 8.3.7) to see more than 32KiB */
2178 if (mdev->agreed_pro_version <= 94)
2179 max_bio_size = min_t(int, max_bio_size, DRBD_MAX_SIZE_H80_PACKET);
2181 p.d_size = cpu_to_be64(d_size);
2182 p.u_size = cpu_to_be64(u_size);
2183 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
2184 p.max_bio_size = cpu_to_be32(max_bio_size);
2185 p.queue_order_type = cpu_to_be16(q_order_type);
2186 p.dds_flags = cpu_to_be16(flags);
2188 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES,
2189 (struct p_header80 *)&p, sizeof(p));
2194 * drbd_send_current_state() - Sends the drbd state to the peer
2195 * @mdev: DRBD device.
2197 int drbd_send_current_state(struct drbd_conf *mdev)
2199 struct socket *sock;
2203 /* Grab state lock so we wont send state if we're in the middle
2204 * of a cluster wide state change on another thread */
2205 drbd_state_lock(mdev);
2207 mutex_lock(&mdev->data.mutex);
2209 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
2210 sock = mdev->data.socket;
2212 if (likely(sock != NULL)) {
2213 ok = _drbd_send_cmd(mdev, sock, P_STATE,
2214 (struct p_header80 *)&p, sizeof(p), 0);
2217 mutex_unlock(&mdev->data.mutex);
2219 drbd_state_unlock(mdev);
2224 * drbd_send_state() - After a state change, sends the new state to the peer
2225 * @mdev: DRBD device.
2226 * @state: the state to send, not necessarily the current state.
2228 * Each state change queues an "after_state_ch" work, which will eventually
2229 * send the resulting new state to the peer. If more state changes happen
2230 * between queuing and processing of the after_state_ch work, we still
2231 * want to send each intermediary state in the order it occurred.
2233 int drbd_send_state(struct drbd_conf *mdev, union drbd_state state)
2235 struct socket *sock;
2239 mutex_lock(&mdev->data.mutex);
2241 p.state = cpu_to_be32(state.i);
2242 sock = mdev->data.socket;
2244 if (likely(sock != NULL)) {
2245 ok = _drbd_send_cmd(mdev, sock, P_STATE,
2246 (struct p_header80 *)&p, sizeof(p), 0);
2249 mutex_unlock(&mdev->data.mutex);
2254 int drbd_send_state_req(struct drbd_conf *mdev,
2255 union drbd_state mask, union drbd_state val)
2257 struct p_req_state p;
2259 p.mask = cpu_to_be32(mask.i);
2260 p.val = cpu_to_be32(val.i);
2262 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ,
2263 (struct p_header80 *)&p, sizeof(p));
2266 int drbd_send_sr_reply(struct drbd_conf *mdev, enum drbd_state_rv retcode)
2268 struct p_req_state_reply p;
2270 p.retcode = cpu_to_be32(retcode);
2272 return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY,
2273 (struct p_header80 *)&p, sizeof(p));
2276 int fill_bitmap_rle_bits(struct drbd_conf *mdev,
2277 struct p_compressed_bm *p,
2278 struct bm_xfer_ctx *c)
2280 struct bitstream bs;
2281 unsigned long plain_bits;
2288 /* may we use this feature? */
2289 if ((mdev->sync_conf.use_rle == 0) ||
2290 (mdev->agreed_pro_version < 90))
2293 if (c->bit_offset >= c->bm_bits)
2294 return 0; /* nothing to do. */
2296 /* use at most thus many bytes */
2297 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
2298 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
2299 /* plain bits covered in this code string */
2302 /* p->encoding & 0x80 stores whether the first run length is set.
2303 * bit offset is implicit.
2304 * start with toggle == 2 to be able to tell the first iteration */
2307 /* see how much plain bits we can stuff into one packet
2308 * using RLE and VLI. */
2310 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
2311 : _drbd_bm_find_next(mdev, c->bit_offset);
2314 rl = tmp - c->bit_offset;
2316 if (toggle == 2) { /* first iteration */
2318 /* the first checked bit was set,
2319 * store start value, */
2320 DCBP_set_start(p, 1);
2321 /* but skip encoding of zero run length */
2325 DCBP_set_start(p, 0);
2328 /* paranoia: catch zero runlength.
2329 * can only happen if bitmap is modified while we scan it. */
2331 dev_err(DEV, "unexpected zero runlength while encoding bitmap "
2332 "t:%u bo:%lu\n", toggle, c->bit_offset);
2336 bits = vli_encode_bits(&bs, rl);
2337 if (bits == -ENOBUFS) /* buffer full */
2340 dev_err(DEV, "error while encoding bitmap: %d\n", bits);
2346 c->bit_offset = tmp;
2347 } while (c->bit_offset < c->bm_bits);
2349 len = bs.cur.b - p->code + !!bs.cur.bit;
2351 if (plain_bits < (len << 3)) {
2352 /* incompressible with this method.
2353 * we need to rewind both word and bit position. */
2354 c->bit_offset -= plain_bits;
2355 bm_xfer_ctx_bit_to_word_offset(c);
2356 c->bit_offset = c->word_offset * BITS_PER_LONG;
2360 /* RLE + VLI was able to compress it just fine.
2361 * update c->word_offset. */
2362 bm_xfer_ctx_bit_to_word_offset(c);
2364 /* store pad_bits */
2365 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
2371 * send_bitmap_rle_or_plain
2373 * Return 0 when done, 1 when another iteration is needed, and a negative error
2374 * code upon failure.
2377 send_bitmap_rle_or_plain(struct drbd_conf *mdev,
2378 struct p_header80 *h, struct bm_xfer_ctx *c)
2380 struct p_compressed_bm *p = (void*)h;
2381 unsigned long num_words;
2385 len = fill_bitmap_rle_bits(mdev, p, c);
2391 DCBP_set_code(p, RLE_VLI_Bits);
2392 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h,
2393 sizeof(*p) + len, 0);
2396 c->bytes[0] += sizeof(*p) + len;
2398 if (c->bit_offset >= c->bm_bits)
2401 /* was not compressible.
2402 * send a buffer full of plain text bits instead. */
2403 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
2404 len = num_words * sizeof(long);
2406 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
2407 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP,
2408 h, sizeof(struct p_header80) + len, 0);
2409 c->word_offset += num_words;
2410 c->bit_offset = c->word_offset * BITS_PER_LONG;
2413 c->bytes[1] += sizeof(struct p_header80) + len;
2415 if (c->bit_offset > c->bm_bits)
2416 c->bit_offset = c->bm_bits;
2420 INFO_bm_xfer_stats(mdev, "send", c);
2428 /* See the comment at receive_bitmap() */
2429 int _drbd_send_bitmap(struct drbd_conf *mdev)
2431 struct bm_xfer_ctx c;
2432 struct p_header80 *p;
2435 ERR_IF(!mdev->bitmap) return false;
2437 /* maybe we should use some per thread scratch page,
2438 * and allocate that during initial device creation? */
2439 p = (struct p_header80 *) __get_free_page(GFP_NOIO);
2441 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
2445 if (get_ldev(mdev)) {
2446 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
2447 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
2448 drbd_bm_set_all(mdev);
2449 if (drbd_bm_write(mdev)) {
2450 /* write_bm did fail! Leave full sync flag set in Meta P_DATA
2451 * but otherwise process as per normal - need to tell other
2452 * side that a full resync is required! */
2453 dev_err(DEV, "Failed to write bitmap to disk!\n");
2455 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2462 c = (struct bm_xfer_ctx) {
2463 .bm_bits = drbd_bm_bits(mdev),
2464 .bm_words = drbd_bm_words(mdev),
2468 err = send_bitmap_rle_or_plain(mdev, p, &c);
2471 free_page((unsigned long) p);
2475 int drbd_send_bitmap(struct drbd_conf *mdev)
2479 if (!drbd_get_data_sock(mdev))
2481 err = !_drbd_send_bitmap(mdev);
2482 drbd_put_data_sock(mdev);
2486 int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
2489 struct p_barrier_ack p;
2491 p.barrier = barrier_nr;
2492 p.set_size = cpu_to_be32(set_size);
2494 if (mdev->state.conn < C_CONNECTED)
2496 ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK,
2497 (struct p_header80 *)&p, sizeof(p));
2502 * _drbd_send_ack() - Sends an ack packet
2503 * @mdev: DRBD device.
2504 * @cmd: Packet command code.
2505 * @sector: sector, needs to be in big endian byte order
2506 * @blksize: size in byte, needs to be in big endian byte order
2507 * @block_id: Id, big endian byte order
2509 static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
2515 struct p_block_ack p;
2518 p.block_id = block_id;
2519 p.blksize = blksize;
2520 p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq));
2522 if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED)
2524 ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd,
2525 (struct p_header80 *)&p, sizeof(p));
2529 /* dp->sector and dp->block_id already/still in network byte order,
2530 * data_size is payload size according to dp->head,
2531 * and may need to be corrected for digest size. */
2532 int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
2533 struct p_data *dp, int data_size)
2535 data_size -= (mdev->agreed_pro_version >= 87 && mdev->integrity_r_tfm) ?
2536 crypto_hash_digestsize(mdev->integrity_r_tfm) : 0;
2537 return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
2541 int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
2542 struct p_block_req *rp)
2544 return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
2548 * drbd_send_ack() - Sends an ack packet
2549 * @mdev: DRBD device.
2550 * @cmd: Packet command code.
2553 int drbd_send_ack(struct drbd_conf *mdev,
2554 enum drbd_packets cmd, struct drbd_epoch_entry *e)
2556 return _drbd_send_ack(mdev, cmd,
2557 cpu_to_be64(e->sector),
2558 cpu_to_be32(e->size),
2562 /* This function misuses the block_id field to signal if the blocks
2563 * are is sync or not. */
2564 int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
2565 sector_t sector, int blksize, u64 block_id)
2567 return _drbd_send_ack(mdev, cmd,
2568 cpu_to_be64(sector),
2569 cpu_to_be32(blksize),
2570 cpu_to_be64(block_id));
2573 int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
2574 sector_t sector, int size, u64 block_id)
2577 struct p_block_req p;
2579 p.sector = cpu_to_be64(sector);
2580 p.block_id = block_id;
2581 p.blksize = cpu_to_be32(size);
2583 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd,
2584 (struct p_header80 *)&p, sizeof(p));
2588 int drbd_send_drequest_csum(struct drbd_conf *mdev,
2589 sector_t sector, int size,
2590 void *digest, int digest_size,
2591 enum drbd_packets cmd)
2594 struct p_block_req p;
2596 p.sector = cpu_to_be64(sector);
2597 p.block_id = BE_DRBD_MAGIC + 0xbeef;
2598 p.blksize = cpu_to_be32(size);
2600 p.head.magic = BE_DRBD_MAGIC;
2601 p.head.command = cpu_to_be16(cmd);
2602 p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header80) + digest_size);
2604 mutex_lock(&mdev->data.mutex);
2606 ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0));
2607 ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0));
2609 mutex_unlock(&mdev->data.mutex);
2614 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
2617 struct p_block_req p;
2619 p.sector = cpu_to_be64(sector);
2620 p.block_id = BE_DRBD_MAGIC + 0xbabe;
2621 p.blksize = cpu_to_be32(size);
2623 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST,
2624 (struct p_header80 *)&p, sizeof(p));
2628 /* called on sndtimeo
2629 * returns false if we should retry,
2630 * true if we think connection is dead
2632 static int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock)
2635 /* long elapsed = (long)(jiffies - mdev->last_received); */
2637 drop_it = mdev->meta.socket == sock
2638 || !mdev->asender.task
2639 || get_t_state(&mdev->asender) != Running
2640 || mdev->state.conn < C_CONNECTED;
2645 drop_it = !--mdev->ko_count;
2647 dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
2648 current->comm, current->pid, mdev->ko_count);
2652 return drop_it; /* && (mdev->state == R_PRIMARY) */;
2655 /* The idea of sendpage seems to be to put some kind of reference
2656 * to the page into the skb, and to hand it over to the NIC. In
2657 * this process get_page() gets called.
2659 * As soon as the page was really sent over the network put_page()
2660 * gets called by some part of the network layer. [ NIC driver? ]
2662 * [ get_page() / put_page() increment/decrement the count. If count
2663 * reaches 0 the page will be freed. ]
2665 * This works nicely with pages from FSs.
2666 * But this means that in protocol A we might signal IO completion too early!
2668 * In order not to corrupt data during a resync we must make sure
2669 * that we do not reuse our own buffer pages (EEs) to early, therefore
2670 * we have the net_ee list.
2672 * XFS seems to have problems, still, it submits pages with page_count == 0!
2673 * As a workaround, we disable sendpage on pages
2674 * with page_count == 0 or PageSlab.
2676 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
2677 int offset, size_t size, unsigned msg_flags)
2679 int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, msg_flags);
2682 mdev->send_cnt += size>>9;
2683 return sent == size;
2686 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
2687 int offset, size_t size, unsigned msg_flags)
2689 mm_segment_t oldfs = get_fs();
2693 /* e.g. XFS meta- & log-data is in slab pages, which have a
2694 * page_count of 0 and/or have PageSlab() set.
2695 * we cannot use send_page for those, as that does get_page();
2696 * put_page(); and would cause either a VM_BUG directly, or
2697 * __page_cache_release a page that would actually still be referenced
2698 * by someone, leading to some obscure delayed Oops somewhere else. */
2699 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
2700 return _drbd_no_send_page(mdev, page, offset, size, msg_flags);
2702 msg_flags |= MSG_NOSIGNAL;
2703 drbd_update_congested(mdev);
2706 sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page,
2709 if (sent == -EAGAIN) {
2710 if (we_should_drop_the_connection(mdev,
2717 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
2718 __func__, (int)size, len, sent);
2723 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
2725 clear_bit(NET_CONGESTED, &mdev->flags);
2729 mdev->send_cnt += size>>9;
2733 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
2735 struct bio_vec *bvec;
2737 /* hint all but last page with MSG_MORE */
2738 __bio_for_each_segment(bvec, bio, i, 0) {
2739 if (!_drbd_no_send_page(mdev, bvec->bv_page,
2740 bvec->bv_offset, bvec->bv_len,
2741 i == bio->bi_vcnt -1 ? 0 : MSG_MORE))
2747 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
2749 struct bio_vec *bvec;
2751 /* hint all but last page with MSG_MORE */
2752 __bio_for_each_segment(bvec, bio, i, 0) {
2753 if (!_drbd_send_page(mdev, bvec->bv_page,
2754 bvec->bv_offset, bvec->bv_len,
2755 i == bio->bi_vcnt -1 ? 0 : MSG_MORE))
2761 static int _drbd_send_zc_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e)
2763 struct page *page = e->pages;
2764 unsigned len = e->size;
2765 /* hint all but last page with MSG_MORE */
2766 page_chain_for_each(page) {
2767 unsigned l = min_t(unsigned, len, PAGE_SIZE);
2768 if (!_drbd_send_page(mdev, page, 0, l,
2769 page_chain_next(page) ? MSG_MORE : 0))
2776 static u32 bio_flags_to_wire(struct drbd_conf *mdev, unsigned long bi_rw)
2778 if (mdev->agreed_pro_version >= 95)
2779 return (bi_rw & REQ_SYNC ? DP_RW_SYNC : 0) |
2780 (bi_rw & REQ_FUA ? DP_FUA : 0) |
2781 (bi_rw & REQ_FLUSH ? DP_FLUSH : 0) |
2782 (bi_rw & REQ_DISCARD ? DP_DISCARD : 0);
2784 return bi_rw & REQ_SYNC ? DP_RW_SYNC : 0;
2787 /* Used to send write requests
2788 * R_PRIMARY -> Peer (P_DATA)
2790 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
2794 unsigned int dp_flags = 0;
2798 if (!drbd_get_data_sock(mdev))
2801 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2802 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2804 if (req->size <= DRBD_MAX_SIZE_H80_PACKET) {
2805 p.head.h80.magic = BE_DRBD_MAGIC;
2806 p.head.h80.command = cpu_to_be16(P_DATA);
2808 cpu_to_be16(sizeof(p) - sizeof(union p_header) + dgs + req->size);
2810 p.head.h95.magic = BE_DRBD_MAGIC_BIG;
2811 p.head.h95.command = cpu_to_be16(P_DATA);
2813 cpu_to_be32(sizeof(p) - sizeof(union p_header) + dgs + req->size);
2816 p.sector = cpu_to_be64(req->sector);
2817 p.block_id = (unsigned long)req;
2818 p.seq_num = cpu_to_be32(req->seq_num =
2819 atomic_add_return(1, &mdev->packet_seq));
2821 dp_flags = bio_flags_to_wire(mdev, req->master_bio->bi_rw);
2823 if (mdev->state.conn >= C_SYNC_SOURCE &&
2824 mdev->state.conn <= C_PAUSED_SYNC_T)
2825 dp_flags |= DP_MAY_SET_IN_SYNC;
2827 p.dp_flags = cpu_to_be32(dp_flags);
2828 set_bit(UNPLUG_REMOTE, &mdev->flags);
2830 drbd_send(mdev, mdev->data.socket, &p, sizeof(p), dgs ? MSG_MORE : 0));
2832 dgb = mdev->int_dig_out;
2833 drbd_csum_bio(mdev, mdev->integrity_w_tfm, req->master_bio, dgb);
2834 ok = dgs == drbd_send(mdev, mdev->data.socket, dgb, dgs, 0);
2837 /* For protocol A, we have to memcpy the payload into
2838 * socket buffers, as we may complete right away
2839 * as soon as we handed it over to tcp, at which point the data
2840 * pages may become invalid.
2842 * For data-integrity enabled, we copy it as well, so we can be
2843 * sure that even if the bio pages may still be modified, it
2844 * won't change the data on the wire, thus if the digest checks
2845 * out ok after sending on this side, but does not fit on the
2846 * receiving side, we sure have detected corruption elsewhere.
2848 if (mdev->net_conf->wire_protocol == DRBD_PROT_A || dgs)
2849 ok = _drbd_send_bio(mdev, req->master_bio);
2851 ok = _drbd_send_zc_bio(mdev, req->master_bio);
2853 /* double check digest, sometimes buffers have been modified in flight. */
2854 if (dgs > 0 && dgs <= 64) {
2855 /* 64 byte, 512 bit, is the largest digest size
2856 * currently supported in kernel crypto. */
2857 unsigned char digest[64];
2858 drbd_csum_bio(mdev, mdev->integrity_w_tfm, req->master_bio, digest);
2859 if (memcmp(mdev->int_dig_out, digest, dgs)) {
2861 "Digest mismatch, buffer modified by upper layers during write: %llus +%u\n",
2862 (unsigned long long)req->sector, req->size);
2864 } /* else if (dgs > 64) {
2865 ... Be noisy about digest too large ...
2869 drbd_put_data_sock(mdev);
2874 /* answer packet, used to send data back for read requests:
2875 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
2876 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
2878 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
2879 struct drbd_epoch_entry *e)
2886 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2887 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2889 if (e->size <= DRBD_MAX_SIZE_H80_PACKET) {
2890 p.head.h80.magic = BE_DRBD_MAGIC;
2891 p.head.h80.command = cpu_to_be16(cmd);
2893 cpu_to_be16(sizeof(p) - sizeof(struct p_header80) + dgs + e->size);
2895 p.head.h95.magic = BE_DRBD_MAGIC_BIG;
2896 p.head.h95.command = cpu_to_be16(cmd);
2898 cpu_to_be32(sizeof(p) - sizeof(struct p_header80) + dgs + e->size);
2901 p.sector = cpu_to_be64(e->sector);
2902 p.block_id = e->block_id;
2903 /* p.seq_num = 0; No sequence numbers here.. */
2905 /* Only called by our kernel thread.
2906 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
2907 * in response to admin command or module unload.
2909 if (!drbd_get_data_sock(mdev))
2912 ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), dgs ? MSG_MORE : 0);
2914 dgb = mdev->int_dig_out;
2915 drbd_csum_ee(mdev, mdev->integrity_w_tfm, e, dgb);
2916 ok = dgs == drbd_send(mdev, mdev->data.socket, dgb, dgs, 0);
2919 ok = _drbd_send_zc_ee(mdev, e);
2921 drbd_put_data_sock(mdev);
2926 int drbd_send_oos(struct drbd_conf *mdev, struct drbd_request *req)
2928 struct p_block_desc p;
2930 p.sector = cpu_to_be64(req->sector);
2931 p.blksize = cpu_to_be32(req->size);
2933 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OUT_OF_SYNC, &p.head, sizeof(p));
2937 drbd_send distinguishes two cases:
2939 Packets sent via the data socket "sock"
2940 and packets sent via the meta data socket "msock"
2943 -----------------+-------------------------+------------------------------
2944 timeout conf.timeout / 2 conf.timeout / 2
2945 timeout action send a ping via msock Abort communication
2946 and close all sockets
2950 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
2952 int drbd_send(struct drbd_conf *mdev, struct socket *sock,
2953 void *buf, size_t size, unsigned msg_flags)
2962 /* THINK if (signal_pending) return ... ? */
2967 msg.msg_name = NULL;
2968 msg.msg_namelen = 0;
2969 msg.msg_control = NULL;
2970 msg.msg_controllen = 0;
2971 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
2973 if (sock == mdev->data.socket) {
2974 mdev->ko_count = mdev->net_conf->ko_count;
2975 drbd_update_congested(mdev);
2979 * tcp_sendmsg does _not_ use its size parameter at all ?
2981 * -EAGAIN on timeout, -EINTR on signal.
2984 * do we need to block DRBD_SIG if sock == &meta.socket ??
2985 * otherwise wake_asender() might interrupt some send_*Ack !
2987 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
2988 if (rv == -EAGAIN) {
2989 if (we_should_drop_the_connection(mdev, sock))
2996 flush_signals(current);
3004 } while (sent < size);
3006 if (sock == mdev->data.socket)
3007 clear_bit(NET_CONGESTED, &mdev->flags);
3010 if (rv != -EAGAIN) {
3011 dev_err(DEV, "%s_sendmsg returned %d\n",
3012 sock == mdev->meta.socket ? "msock" : "sock",
3014 drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE));
3016 drbd_force_state(mdev, NS(conn, C_TIMEOUT));
3022 static int drbd_open(struct block_device *bdev, fmode_t mode)
3024 struct drbd_conf *mdev = bdev->bd_disk->private_data;
3025 unsigned long flags;
3028 mutex_lock(&drbd_main_mutex);
3029 spin_lock_irqsave(&mdev->req_lock, flags);
3030 /* to have a stable mdev->state.role
3031 * and no race with updating open_cnt */
3033 if (mdev->state.role != R_PRIMARY) {
3034 if (mode & FMODE_WRITE)
3036 else if (!allow_oos)
3042 spin_unlock_irqrestore(&mdev->req_lock, flags);
3043 mutex_unlock(&drbd_main_mutex);
3048 static int drbd_release(struct gendisk *gd, fmode_t mode)
3050 struct drbd_conf *mdev = gd->private_data;
3051 mutex_lock(&drbd_main_mutex);
3053 mutex_unlock(&drbd_main_mutex);
3057 static void drbd_set_defaults(struct drbd_conf *mdev)
3059 /* This way we get a compile error when sync_conf grows,
3060 and we forgot to initialize it here */
3061 mdev->sync_conf = (struct syncer_conf) {
3062 /* .rate = */ DRBD_RATE_DEF,
3063 /* .after = */ DRBD_AFTER_DEF,
3064 /* .al_extents = */ DRBD_AL_EXTENTS_DEF,
3065 /* .verify_alg = */ {}, 0,
3066 /* .cpu_mask = */ {}, 0,
3067 /* .csums_alg = */ {}, 0,
3069 /* .on_no_data = */ DRBD_ON_NO_DATA_DEF,
3070 /* .c_plan_ahead = */ DRBD_C_PLAN_AHEAD_DEF,
3071 /* .c_delay_target = */ DRBD_C_DELAY_TARGET_DEF,
3072 /* .c_fill_target = */ DRBD_C_FILL_TARGET_DEF,
3073 /* .c_max_rate = */ DRBD_C_MAX_RATE_DEF,
3074 /* .c_min_rate = */ DRBD_C_MIN_RATE_DEF
3077 /* Have to use that way, because the layout differs between
3078 big endian and little endian */
3079 mdev->state = (union drbd_state) {
3080 { .role = R_SECONDARY,
3082 .conn = C_STANDALONE,
3091 void drbd_init_set_defaults(struct drbd_conf *mdev)
3093 /* the memset(,0,) did most of this.
3094 * note: only assignments, no allocation in here */
3096 drbd_set_defaults(mdev);
3098 atomic_set(&mdev->ap_bio_cnt, 0);
3099 atomic_set(&mdev->ap_pending_cnt, 0);
3100 atomic_set(&mdev->rs_pending_cnt, 0);
3101 atomic_set(&mdev->unacked_cnt, 0);
3102 atomic_set(&mdev->local_cnt, 0);
3103 atomic_set(&mdev->net_cnt, 0);
3104 atomic_set(&mdev->packet_seq, 0);
3105 atomic_set(&mdev->pp_in_use, 0);
3106 atomic_set(&mdev->pp_in_use_by_net, 0);
3107 atomic_set(&mdev->rs_sect_in, 0);
3108 atomic_set(&mdev->rs_sect_ev, 0);
3109 atomic_set(&mdev->ap_in_flight, 0);
3110 atomic_set(&mdev->md_io_in_use, 0);
3112 mutex_init(&mdev->data.mutex);
3113 mutex_init(&mdev->meta.mutex);
3114 sema_init(&mdev->data.work.s, 0);
3115 sema_init(&mdev->meta.work.s, 0);
3116 mutex_init(&mdev->state_mutex);
3118 spin_lock_init(&mdev->data.work.q_lock);
3119 spin_lock_init(&mdev->meta.work.q_lock);
3121 spin_lock_init(&mdev->al_lock);
3122 spin_lock_init(&mdev->req_lock);
3123 spin_lock_init(&mdev->peer_seq_lock);
3124 spin_lock_init(&mdev->epoch_lock);
3126 INIT_LIST_HEAD(&mdev->active_ee);
3127 INIT_LIST_HEAD(&mdev->sync_ee);
3128 INIT_LIST_HEAD(&mdev->done_ee);
3129 INIT_LIST_HEAD(&mdev->read_ee);
3130 INIT_LIST_HEAD(&mdev->net_ee);
3131 INIT_LIST_HEAD(&mdev->resync_reads);
3132 INIT_LIST_HEAD(&mdev->data.work.q);
3133 INIT_LIST_HEAD(&mdev->meta.work.q);
3134 INIT_LIST_HEAD(&mdev->resync_work.list);
3135 INIT_LIST_HEAD(&mdev->unplug_work.list);
3136 INIT_LIST_HEAD(&mdev->go_diskless.list);
3137 INIT_LIST_HEAD(&mdev->md_sync_work.list);
3138 INIT_LIST_HEAD(&mdev->start_resync_work.list);
3139 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
3141 mdev->resync_work.cb = w_resync_timer;
3142 mdev->unplug_work.cb = w_send_write_hint;
3143 mdev->go_diskless.cb = w_go_diskless;
3144 mdev->md_sync_work.cb = w_md_sync;
3145 mdev->bm_io_work.w.cb = w_bitmap_io;
3146 mdev->start_resync_work.cb = w_start_resync;
3147 init_timer(&mdev->resync_timer);
3148 init_timer(&mdev->md_sync_timer);
3149 init_timer(&mdev->start_resync_timer);
3150 init_timer(&mdev->request_timer);
3151 mdev->resync_timer.function = resync_timer_fn;
3152 mdev->resync_timer.data = (unsigned long) mdev;
3153 mdev->md_sync_timer.function = md_sync_timer_fn;
3154 mdev->md_sync_timer.data = (unsigned long) mdev;
3155 mdev->start_resync_timer.function = start_resync_timer_fn;
3156 mdev->start_resync_timer.data = (unsigned long) mdev;
3157 mdev->request_timer.function = request_timer_fn;
3158 mdev->request_timer.data = (unsigned long) mdev;
3160 init_waitqueue_head(&mdev->misc_wait);
3161 init_waitqueue_head(&mdev->state_wait);
3162 init_waitqueue_head(&mdev->net_cnt_wait);
3163 init_waitqueue_head(&mdev->ee_wait);
3164 init_waitqueue_head(&mdev->al_wait);
3165 init_waitqueue_head(&mdev->seq_wait);
3167 drbd_thread_init(mdev, &mdev->receiver, drbdd_init);
3168 drbd_thread_init(mdev, &mdev->worker, drbd_worker);
3169 drbd_thread_init(mdev, &mdev->asender, drbd_asender);
3171 mdev->agreed_pro_version = PRO_VERSION_MAX;
3172 mdev->write_ordering = WO_bdev_flush;
3173 mdev->resync_wenr = LC_FREE;
3174 mdev->peer_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
3175 mdev->local_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
3178 void drbd_mdev_cleanup(struct drbd_conf *mdev)
3181 if (mdev->receiver.t_state != None)
3182 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
3183 mdev->receiver.t_state);
3185 /* no need to lock it, I'm the only thread alive */
3186 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
3187 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
3197 mdev->rs_failed = 0;
3198 mdev->rs_last_events = 0;
3199 mdev->rs_last_sect_ev = 0;
3200 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
3201 mdev->rs_mark_left[i] = 0;
3202 mdev->rs_mark_time[i] = 0;
3204 D_ASSERT(mdev->net_conf == NULL);
3206 drbd_set_my_capacity(mdev, 0);
3208 /* maybe never allocated. */
3209 drbd_bm_resize(mdev, 0, 1);
3210 drbd_bm_cleanup(mdev);
3213 drbd_free_resources(mdev);
3214 clear_bit(AL_SUSPENDED, &mdev->flags);
3217 * currently we drbd_init_ee only on module load, so
3218 * we may do drbd_release_ee only on module unload!
3220 D_ASSERT(list_empty(&mdev->active_ee));
3221 D_ASSERT(list_empty(&mdev->sync_ee));
3222 D_ASSERT(list_empty(&mdev->done_ee));
3223 D_ASSERT(list_empty(&mdev->read_ee));
3224 D_ASSERT(list_empty(&mdev->net_ee));
3225 D_ASSERT(list_empty(&mdev->resync_reads));
3226 D_ASSERT(list_empty(&mdev->data.work.q));
3227 D_ASSERT(list_empty(&mdev->meta.work.q));
3228 D_ASSERT(list_empty(&mdev->resync_work.list));
3229 D_ASSERT(list_empty(&mdev->unplug_work.list));
3230 D_ASSERT(list_empty(&mdev->go_diskless.list));
3232 drbd_set_defaults(mdev);
3236 static void drbd_destroy_mempools(void)
3240 while (drbd_pp_pool) {
3241 page = drbd_pp_pool;
3242 drbd_pp_pool = (struct page *)page_private(page);
3247 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
3249 if (drbd_ee_mempool)
3250 mempool_destroy(drbd_ee_mempool);
3251 if (drbd_request_mempool)
3252 mempool_destroy(drbd_request_mempool);
3254 kmem_cache_destroy(drbd_ee_cache);
3255 if (drbd_request_cache)
3256 kmem_cache_destroy(drbd_request_cache);
3257 if (drbd_bm_ext_cache)
3258 kmem_cache_destroy(drbd_bm_ext_cache);
3259 if (drbd_al_ext_cache)
3260 kmem_cache_destroy(drbd_al_ext_cache);
3262 drbd_ee_mempool = NULL;
3263 drbd_request_mempool = NULL;
3264 drbd_ee_cache = NULL;
3265 drbd_request_cache = NULL;
3266 drbd_bm_ext_cache = NULL;
3267 drbd_al_ext_cache = NULL;
3272 static int drbd_create_mempools(void)
3275 const int number = (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count;
3278 /* prepare our caches and mempools */
3279 drbd_request_mempool = NULL;
3280 drbd_ee_cache = NULL;
3281 drbd_request_cache = NULL;
3282 drbd_bm_ext_cache = NULL;
3283 drbd_al_ext_cache = NULL;
3284 drbd_pp_pool = NULL;
3287 drbd_request_cache = kmem_cache_create(
3288 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
3289 if (drbd_request_cache == NULL)
3292 drbd_ee_cache = kmem_cache_create(
3293 "drbd_ee", sizeof(struct drbd_epoch_entry), 0, 0, NULL);
3294 if (drbd_ee_cache == NULL)
3297 drbd_bm_ext_cache = kmem_cache_create(
3298 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
3299 if (drbd_bm_ext_cache == NULL)
3302 drbd_al_ext_cache = kmem_cache_create(
3303 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
3304 if (drbd_al_ext_cache == NULL)
3308 drbd_request_mempool = mempool_create(number,
3309 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
3310 if (drbd_request_mempool == NULL)
3313 drbd_ee_mempool = mempool_create(number,
3314 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
3315 if (drbd_ee_mempool == NULL)
3318 /* drbd's page pool */
3319 spin_lock_init(&drbd_pp_lock);
3321 for (i = 0; i < number; i++) {
3322 page = alloc_page(GFP_HIGHUSER);
3325 set_page_private(page, (unsigned long)drbd_pp_pool);
3326 drbd_pp_pool = page;
3328 drbd_pp_vacant = number;
3333 drbd_destroy_mempools(); /* in case we allocated some */
3337 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
3340 /* just so we have it. you never know what interesting things we
3341 * might want to do here some day...
3347 static struct notifier_block drbd_notifier = {
3348 .notifier_call = drbd_notify_sys,
3351 static void drbd_release_ee_lists(struct drbd_conf *mdev)
3355 rr = drbd_release_ee(mdev, &mdev->active_ee);
3357 dev_err(DEV, "%d EEs in active list found!\n", rr);
3359 rr = drbd_release_ee(mdev, &mdev->sync_ee);
3361 dev_err(DEV, "%d EEs in sync list found!\n", rr);
3363 rr = drbd_release_ee(mdev, &mdev->read_ee);
3365 dev_err(DEV, "%d EEs in read list found!\n", rr);
3367 rr = drbd_release_ee(mdev, &mdev->done_ee);
3369 dev_err(DEV, "%d EEs in done list found!\n", rr);
3371 rr = drbd_release_ee(mdev, &mdev->net_ee);
3373 dev_err(DEV, "%d EEs in net list found!\n", rr);
3376 /* caution. no locking.
3377 * currently only used from module cleanup code. */
3378 static void drbd_delete_device(unsigned int minor)
3380 struct drbd_conf *mdev = minor_to_mdev(minor);
3385 del_timer_sync(&mdev->request_timer);
3387 /* paranoia asserts */
3388 if (mdev->open_cnt != 0)
3389 dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,
3390 __FILE__ , __LINE__);
3392 ERR_IF (!list_empty(&mdev->data.work.q)) {
3393 struct list_head *lp;
3394 list_for_each(lp, &mdev->data.work.q) {
3395 dev_err(DEV, "lp = %p\n", lp);
3398 /* end paranoia asserts */
3400 del_gendisk(mdev->vdisk);
3402 /* cleanup stuff that may have been allocated during
3403 * device (re-)configuration or state changes */
3405 if (mdev->this_bdev)
3406 bdput(mdev->this_bdev);
3408 drbd_free_resources(mdev);
3410 drbd_release_ee_lists(mdev);
3412 /* should be freed on disconnect? */
3413 kfree(mdev->ee_hash);
3415 mdev->ee_hash_s = 0;
3416 mdev->ee_hash = NULL;
3419 lc_destroy(mdev->act_log);
3420 lc_destroy(mdev->resync);
3422 kfree(mdev->p_uuid);
3423 /* mdev->p_uuid = NULL; */
3425 kfree(mdev->int_dig_out);
3426 kfree(mdev->int_dig_in);
3427 kfree(mdev->int_dig_vv);
3429 /* cleanup the rest that has been
3430 * allocated from drbd_new_device
3431 * and actually free the mdev itself */
3432 drbd_free_mdev(mdev);
3435 static void drbd_cleanup(void)
3439 unregister_reboot_notifier(&drbd_notifier);
3441 /* first remove proc,
3442 * drbdsetup uses it's presence to detect
3443 * whether DRBD is loaded.
3444 * If we would get stuck in proc removal,
3445 * but have netlink already deregistered,
3446 * some drbdsetup commands may wait forever
3450 remove_proc_entry("drbd", NULL);
3457 drbd_delete_device(i);
3458 drbd_destroy_mempools();
3463 unregister_blkdev(DRBD_MAJOR, "drbd");
3465 printk(KERN_INFO "drbd: module cleanup done.\n");
3469 * drbd_congested() - Callback for pdflush
3470 * @congested_data: User data
3471 * @bdi_bits: Bits pdflush is currently interested in
3473 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
3475 static int drbd_congested(void *congested_data, int bdi_bits)
3477 struct drbd_conf *mdev = congested_data;
3478 struct request_queue *q;
3482 if (!may_inc_ap_bio(mdev)) {
3483 /* DRBD has frozen IO */
3489 if (get_ldev(mdev)) {
3490 q = bdev_get_queue(mdev->ldev->backing_bdev);
3491 r = bdi_congested(&q->backing_dev_info, bdi_bits);
3497 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) {
3498 r |= (1 << BDI_async_congested);
3499 reason = reason == 'b' ? 'a' : 'n';
3503 mdev->congestion_reason = reason;
3507 struct drbd_conf *drbd_new_device(unsigned int minor)
3509 struct drbd_conf *mdev;
3510 struct gendisk *disk;
3511 struct request_queue *q;
3513 /* GFP_KERNEL, we are outside of all write-out paths */
3514 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
3517 if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL))
3518 goto out_no_cpumask;
3520 mdev->minor = minor;
3522 drbd_init_set_defaults(mdev);
3524 q = blk_alloc_queue(GFP_KERNEL);
3528 q->queuedata = mdev;
3530 disk = alloc_disk(1);
3535 set_disk_ro(disk, true);
3538 disk->major = DRBD_MAJOR;
3539 disk->first_minor = minor;
3540 disk->fops = &drbd_ops;
3541 sprintf(disk->disk_name, "drbd%d", minor);
3542 disk->private_data = mdev;
3544 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
3545 /* we have no partitions. we contain only ourselves. */
3546 mdev->this_bdev->bd_contains = mdev->this_bdev;
3548 q->backing_dev_info.congested_fn = drbd_congested;
3549 q->backing_dev_info.congested_data = mdev;
3551 blk_queue_make_request(q, drbd_make_request);
3552 /* Setting the max_hw_sectors to an odd value of 8kibyte here
3553 This triggers a max_bio_size message upon first attach or connect */
3554 blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8);
3555 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
3556 blk_queue_merge_bvec(q, drbd_merge_bvec);
3557 q->queue_lock = &mdev->req_lock;
3559 mdev->md_io_page = alloc_page(GFP_KERNEL);
3560 if (!mdev->md_io_page)
3561 goto out_no_io_page;
3563 if (drbd_bm_init(mdev))
3565 /* no need to lock access, we are still initializing this minor device. */
3569 mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL);
3570 if (!mdev->app_reads_hash)
3571 goto out_no_app_reads;
3573 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
3574 if (!mdev->current_epoch)
3577 INIT_LIST_HEAD(&mdev->current_epoch->list);
3582 /* out_whatever_else:
3583 kfree(mdev->current_epoch); */
3585 kfree(mdev->app_reads_hash);
3589 drbd_bm_cleanup(mdev);
3591 __free_page(mdev->md_io_page);
3595 blk_cleanup_queue(q);
3597 free_cpumask_var(mdev->cpu_mask);
3603 /* counterpart of drbd_new_device.
3604 * last part of drbd_delete_device. */
3605 void drbd_free_mdev(struct drbd_conf *mdev)
3607 kfree(mdev->current_epoch);
3608 kfree(mdev->app_reads_hash);
3610 if (mdev->bitmap) /* should no longer be there. */
3611 drbd_bm_cleanup(mdev);
3612 __free_page(mdev->md_io_page);
3613 put_disk(mdev->vdisk);
3614 blk_cleanup_queue(mdev->rq_queue);
3615 free_cpumask_var(mdev->cpu_mask);
3616 drbd_free_tl_hash(mdev);
3621 int __init drbd_init(void)
3625 if (sizeof(struct p_handshake) != 80) {
3627 "drbd: never change the size or layout "
3628 "of the HandShake packet.\n");
3632 if (minor_count < DRBD_MINOR_COUNT_MIN || minor_count > DRBD_MINOR_COUNT_MAX) {
3634 "drbd: invalid minor_count (%d)\n", minor_count);
3642 err = drbd_nl_init();
3646 err = register_blkdev(DRBD_MAJOR, "drbd");
3649 "drbd: unable to register block device major %d\n",
3654 register_reboot_notifier(&drbd_notifier);
3657 * allocate all necessary structs
3661 init_waitqueue_head(&drbd_pp_wait);
3663 drbd_proc = NULL; /* play safe for drbd_cleanup */
3664 minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
3669 err = drbd_create_mempools();
3673 drbd_proc = proc_create_data("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops, NULL);
3675 printk(KERN_ERR "drbd: unable to register proc file\n");
3679 rwlock_init(&global_state_lock);
3681 printk(KERN_INFO "drbd: initialized. "
3682 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
3683 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
3684 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
3685 printk(KERN_INFO "drbd: registered as block device major %d\n",
3687 printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
3689 return 0; /* Success! */
3694 /* currently always the case */
3695 printk(KERN_ERR "drbd: ran out of memory\n");
3697 printk(KERN_ERR "drbd: initialization failure\n");
3701 void drbd_free_bc(struct drbd_backing_dev *ldev)
3706 blkdev_put(ldev->backing_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
3707 blkdev_put(ldev->md_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
3712 void drbd_free_sock(struct drbd_conf *mdev)
3714 if (mdev->data.socket) {
3715 mutex_lock(&mdev->data.mutex);
3716 kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR);
3717 sock_release(mdev->data.socket);
3718 mdev->data.socket = NULL;
3719 mutex_unlock(&mdev->data.mutex);
3721 if (mdev->meta.socket) {
3722 mutex_lock(&mdev->meta.mutex);
3723 kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR);
3724 sock_release(mdev->meta.socket);
3725 mdev->meta.socket = NULL;
3726 mutex_unlock(&mdev->meta.mutex);
3731 void drbd_free_resources(struct drbd_conf *mdev)
3733 crypto_free_hash(mdev->csums_tfm);
3734 mdev->csums_tfm = NULL;
3735 crypto_free_hash(mdev->verify_tfm);
3736 mdev->verify_tfm = NULL;
3737 crypto_free_hash(mdev->cram_hmac_tfm);
3738 mdev->cram_hmac_tfm = NULL;
3739 crypto_free_hash(mdev->integrity_w_tfm);
3740 mdev->integrity_w_tfm = NULL;
3741 crypto_free_hash(mdev->integrity_r_tfm);
3742 mdev->integrity_r_tfm = NULL;
3744 drbd_free_sock(mdev);
3747 drbd_free_bc(mdev->ldev);
3748 mdev->ldev = NULL;);
3751 /* meta data management */
3753 struct meta_data_on_disk {
3754 u64 la_size; /* last agreed size. */
3755 u64 uuid[UI_SIZE]; /* UUIDs. */
3758 u32 flags; /* MDF */
3761 u32 al_offset; /* offset to this block */
3762 u32 al_nr_extents; /* important for restoring the AL */
3763 /* `-- act_log->nr_elements <-- sync_conf.al_extents */
3764 u32 bm_offset; /* offset to the bitmap, from here */
3765 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
3766 u32 la_peer_max_bio_size; /* last peer max_bio_size */
3767 u32 reserved_u32[3];
3772 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
3773 * @mdev: DRBD device.
3775 void drbd_md_sync(struct drbd_conf *mdev)
3777 struct meta_data_on_disk *buffer;
3781 del_timer(&mdev->md_sync_timer);
3782 /* timer may be rearmed by drbd_md_mark_dirty() now. */
3783 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
3786 /* We use here D_FAILED and not D_ATTACHING because we try to write
3787 * metadata even if we detach due to a disk failure! */
3788 if (!get_ldev_if_state(mdev, D_FAILED))
3791 buffer = drbd_md_get_buffer(mdev);
3795 memset(buffer, 0, 512);
3797 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
3798 for (i = UI_CURRENT; i < UI_SIZE; i++)
3799 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
3800 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
3801 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
3803 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
3804 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
3805 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
3806 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
3807 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
3809 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
3810 buffer->la_peer_max_bio_size = cpu_to_be32(mdev->peer_max_bio_size);
3812 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
3813 sector = mdev->ldev->md.md_offset;
3815 if (!drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
3816 /* this was a try anyways ... */
3817 dev_err(DEV, "meta data update failed!\n");
3818 drbd_chk_io_error(mdev, 1, true);
3821 /* Update mdev->ldev->md.la_size_sect,
3822 * since we updated it on metadata. */
3823 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
3825 drbd_md_put_buffer(mdev);
3831 * drbd_md_read() - Reads in the meta data super block
3832 * @mdev: DRBD device.
3833 * @bdev: Device from which the meta data should be read in.
3835 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_code in case
3836 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
3838 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
3840 struct meta_data_on_disk *buffer;
3841 int i, rv = NO_ERROR;
3843 if (!get_ldev_if_state(mdev, D_ATTACHING))
3844 return ERR_IO_MD_DISK;
3846 buffer = drbd_md_get_buffer(mdev);
3850 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
3851 /* NOTE: can't do normal error processing here as this is
3852 called BEFORE disk is attached */
3853 dev_err(DEV, "Error while reading metadata.\n");
3854 rv = ERR_IO_MD_DISK;
3858 if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) {
3859 dev_err(DEV, "Error while reading metadata, magic not found.\n");
3860 rv = ERR_MD_INVALID;
3863 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
3864 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
3865 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
3866 rv = ERR_MD_INVALID;
3869 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
3870 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
3871 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
3872 rv = ERR_MD_INVALID;
3875 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
3876 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
3877 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
3878 rv = ERR_MD_INVALID;
3882 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
3883 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
3884 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
3885 rv = ERR_MD_INVALID;
3889 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
3890 for (i = UI_CURRENT; i < UI_SIZE; i++)
3891 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
3892 bdev->md.flags = be32_to_cpu(buffer->flags);
3893 mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents);
3894 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
3896 spin_lock_irq(&mdev->req_lock);
3897 if (mdev->state.conn < C_CONNECTED) {
3899 peer = be32_to_cpu(buffer->la_peer_max_bio_size);
3900 peer = max_t(int, peer, DRBD_MAX_BIO_SIZE_SAFE);
3901 mdev->peer_max_bio_size = peer;
3903 spin_unlock_irq(&mdev->req_lock);
3905 if (mdev->sync_conf.al_extents < 7)
3906 mdev->sync_conf.al_extents = 127;
3909 drbd_md_put_buffer(mdev);
3917 * drbd_md_mark_dirty() - Mark meta data super block as dirty
3918 * @mdev: DRBD device.
3920 * Call this function if you change anything that should be written to
3921 * the meta-data super block. This function sets MD_DIRTY, and starts a
3922 * timer that ensures that within five seconds you have to call drbd_md_sync().
3925 void drbd_md_mark_dirty_(struct drbd_conf *mdev, unsigned int line, const char *func)
3927 if (!test_and_set_bit(MD_DIRTY, &mdev->flags)) {
3928 mod_timer(&mdev->md_sync_timer, jiffies + HZ);
3929 mdev->last_md_mark_dirty.line = line;
3930 mdev->last_md_mark_dirty.func = func;
3934 void drbd_md_mark_dirty(struct drbd_conf *mdev)
3936 if (!test_and_set_bit(MD_DIRTY, &mdev->flags))
3937 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
3941 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
3945 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
3946 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
3949 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3951 if (idx == UI_CURRENT) {
3952 if (mdev->state.role == R_PRIMARY)
3957 drbd_set_ed_uuid(mdev, val);
3960 mdev->ldev->md.uuid[idx] = val;
3961 drbd_md_mark_dirty(mdev);
3965 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3967 if (mdev->ldev->md.uuid[idx]) {
3968 drbd_uuid_move_history(mdev);
3969 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
3971 _drbd_uuid_set(mdev, idx, val);
3975 * drbd_uuid_new_current() - Creates a new current UUID
3976 * @mdev: DRBD device.
3978 * Creates a new current UUID, and rotates the old current UUID into
3979 * the bitmap slot. Causes an incremental resync upon next connect.
3981 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
3984 unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];
3987 dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
3989 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
3991 get_random_bytes(&val, sizeof(u64));
3992 _drbd_uuid_set(mdev, UI_CURRENT, val);
3993 drbd_print_uuids(mdev, "new current UUID");
3994 /* get it to stable storage _now_ */
3998 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
4000 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
4004 drbd_uuid_move_history(mdev);
4005 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
4006 mdev->ldev->md.uuid[UI_BITMAP] = 0;
4008 unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];
4010 dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
4012 mdev->ldev->md.uuid[UI_BITMAP] = val & ~((u64)1);
4014 drbd_md_mark_dirty(mdev);
4018 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
4019 * @mdev: DRBD device.
4021 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
4023 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
4027 if (get_ldev_if_state(mdev, D_ATTACHING)) {
4028 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
4030 drbd_bm_set_all(mdev);
4032 rv = drbd_bm_write(mdev);
4035 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
4046 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
4047 * @mdev: DRBD device.
4049 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
4051 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
4055 drbd_resume_al(mdev);
4056 if (get_ldev_if_state(mdev, D_ATTACHING)) {
4057 drbd_bm_clear_all(mdev);
4058 rv = drbd_bm_write(mdev);
4065 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused)
4067 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
4070 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
4072 if (get_ldev(mdev)) {
4073 drbd_bm_lock(mdev, work->why, work->flags);
4074 rv = work->io_fn(mdev);
4075 drbd_bm_unlock(mdev);
4079 clear_bit(BITMAP_IO, &mdev->flags);
4080 smp_mb__after_clear_bit();
4081 wake_up(&mdev->misc_wait);
4084 work->done(mdev, rv);
4086 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
4093 void drbd_ldev_destroy(struct drbd_conf *mdev)
4095 lc_destroy(mdev->resync);
4096 mdev->resync = NULL;
4097 lc_destroy(mdev->act_log);
4098 mdev->act_log = NULL;
4100 drbd_free_bc(mdev->ldev);
4101 mdev->ldev = NULL;);
4103 if (mdev->md_io_tmpp) {
4104 __free_page(mdev->md_io_tmpp);
4105 mdev->md_io_tmpp = NULL;
4107 clear_bit(GO_DISKLESS, &mdev->flags);
4110 static int w_go_diskless(struct drbd_conf *mdev, struct drbd_work *w, int unused)
4112 D_ASSERT(mdev->state.disk == D_FAILED);
4113 /* we cannot assert local_cnt == 0 here, as get_ldev_if_state will
4114 * inc/dec it frequently. Once we are D_DISKLESS, no one will touch
4115 * the protected members anymore, though, so once put_ldev reaches zero
4116 * again, it will be safe to free them. */
4117 drbd_force_state(mdev, NS(disk, D_DISKLESS));
4121 void drbd_go_diskless(struct drbd_conf *mdev)
4123 D_ASSERT(mdev->state.disk == D_FAILED);
4124 if (!test_and_set_bit(GO_DISKLESS, &mdev->flags))
4125 drbd_queue_work(&mdev->data.work, &mdev->go_diskless);
4129 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
4130 * @mdev: DRBD device.
4131 * @io_fn: IO callback to be called when bitmap IO is possible
4132 * @done: callback to be called after the bitmap IO was performed
4133 * @why: Descriptive text of the reason for doing the IO
4135 * While IO on the bitmap happens we freeze application IO thus we ensure
4136 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
4137 * called from worker context. It MUST NOT be used while a previous such
4138 * work is still pending!
4140 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
4141 int (*io_fn)(struct drbd_conf *),
4142 void (*done)(struct drbd_conf *, int),
4143 char *why, enum bm_flag flags)
4145 D_ASSERT(current == mdev->worker.task);
4147 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
4148 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
4149 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
4150 if (mdev->bm_io_work.why)
4151 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
4152 why, mdev->bm_io_work.why);
4154 mdev->bm_io_work.io_fn = io_fn;
4155 mdev->bm_io_work.done = done;
4156 mdev->bm_io_work.why = why;
4157 mdev->bm_io_work.flags = flags;
4159 spin_lock_irq(&mdev->req_lock);
4160 set_bit(BITMAP_IO, &mdev->flags);
4161 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
4162 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
4163 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
4165 spin_unlock_irq(&mdev->req_lock);
4169 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
4170 * @mdev: DRBD device.
4171 * @io_fn: IO callback to be called when bitmap IO is possible
4172 * @why: Descriptive text of the reason for doing the IO
4174 * freezes application IO while that the actual IO operations runs. This
4175 * functions MAY NOT be called from worker context.
4177 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *),
4178 char *why, enum bm_flag flags)
4182 D_ASSERT(current != mdev->worker.task);
4184 if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
4185 drbd_suspend_io(mdev);
4187 drbd_bm_lock(mdev, why, flags);
4189 drbd_bm_unlock(mdev);
4191 if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
4192 drbd_resume_io(mdev);
4197 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
4199 if ((mdev->ldev->md.flags & flag) != flag) {
4200 drbd_md_mark_dirty(mdev);
4201 mdev->ldev->md.flags |= flag;
4205 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
4207 if ((mdev->ldev->md.flags & flag) != 0) {
4208 drbd_md_mark_dirty(mdev);
4209 mdev->ldev->md.flags &= ~flag;
4212 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
4214 return (bdev->md.flags & flag) != 0;
4217 static void md_sync_timer_fn(unsigned long data)
4219 struct drbd_conf *mdev = (struct drbd_conf *) data;
4221 drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work);
4224 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused)
4226 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
4228 dev_warn(DEV, "last md_mark_dirty: %s:%u\n",
4229 mdev->last_md_mark_dirty.func, mdev->last_md_mark_dirty.line);
4235 #ifdef CONFIG_DRBD_FAULT_INJECTION
4236 /* Fault insertion support including random number generator shamelessly
4237 * stolen from kernel/rcutorture.c */
4238 struct fault_random_state {
4239 unsigned long state;
4240 unsigned long count;
4243 #define FAULT_RANDOM_MULT 39916801 /* prime */
4244 #define FAULT_RANDOM_ADD 479001701 /* prime */
4245 #define FAULT_RANDOM_REFRESH 10000
4248 * Crude but fast random-number generator. Uses a linear congruential
4249 * generator, with occasional help from get_random_bytes().
4251 static unsigned long
4252 _drbd_fault_random(struct fault_random_state *rsp)
4256 if (!rsp->count--) {
4257 get_random_bytes(&refresh, sizeof(refresh));
4258 rsp->state += refresh;
4259 rsp->count = FAULT_RANDOM_REFRESH;
4261 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
4262 return swahw32(rsp->state);
4266 _drbd_fault_str(unsigned int type) {
4267 static char *_faults[] = {
4268 [DRBD_FAULT_MD_WR] = "Meta-data write",
4269 [DRBD_FAULT_MD_RD] = "Meta-data read",
4270 [DRBD_FAULT_RS_WR] = "Resync write",
4271 [DRBD_FAULT_RS_RD] = "Resync read",
4272 [DRBD_FAULT_DT_WR] = "Data write",
4273 [DRBD_FAULT_DT_RD] = "Data read",
4274 [DRBD_FAULT_DT_RA] = "Data read ahead",
4275 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
4276 [DRBD_FAULT_AL_EE] = "EE allocation",
4277 [DRBD_FAULT_RECEIVE] = "receive data corruption",
4280 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
4284 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
4286 static struct fault_random_state rrs = {0, 0};
4288 unsigned int ret = (
4290 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
4291 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
4296 if (__ratelimit(&drbd_ratelimit_state))
4297 dev_warn(DEV, "***Simulating %s failure\n",
4298 _drbd_fault_str(type));
4305 const char *drbd_buildtag(void)
4307 /* DRBD built from external sources has here a reference to the
4308 git hash of the source code. */
4310 static char buildtag[38] = "\0uilt-in";
4312 if (buildtag[0] == 0) {
4313 #ifdef CONFIG_MODULES
4314 if (THIS_MODULE != NULL)
4315 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
4324 module_init(drbd_init)
4325 module_exit(drbd_cleanup)
4327 EXPORT_SYMBOL(drbd_conn_str);
4328 EXPORT_SYMBOL(drbd_role_str);
4329 EXPORT_SYMBOL(drbd_disk_str);
4330 EXPORT_SYMBOL(drbd_set_st_err_str);