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 (1-255)");
89 MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR);
91 #include <linux/moduleparam.h>
92 /* allow_open_on_secondary */
93 MODULE_PARM_DESC(allow_oos, "DONT USE!");
94 /* thanks to these macros, if compiled into the kernel (not-module),
95 * this becomes the boot parameter drbd.minor_count */
96 module_param(minor_count, uint, 0444);
97 module_param(disable_sendpage, bool, 0644);
98 module_param(allow_oos, bool, 0);
99 module_param(cn_idx, uint, 0444);
100 module_param(proc_details, int, 0644);
102 #ifdef CONFIG_DRBD_FAULT_INJECTION
105 static int fault_count;
107 /* bitmap of enabled faults */
108 module_param(enable_faults, int, 0664);
109 /* fault rate % value - applies to all enabled faults */
110 module_param(fault_rate, int, 0664);
111 /* count of faults inserted */
112 module_param(fault_count, int, 0664);
113 /* bitmap of devices to insert faults on */
114 module_param(fault_devs, int, 0644);
117 /* module parameter, defined */
118 unsigned int minor_count = 32;
119 int disable_sendpage;
121 unsigned int cn_idx = CN_IDX_DRBD;
122 int proc_details; /* Detail level in proc drbd*/
124 /* Module parameter for setting the user mode helper program
125 * to run. Default is /sbin/drbdadm */
126 char usermode_helper[80] = "/sbin/drbdadm";
128 module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644);
130 /* in 2.6.x, our device mapping and config info contains our virtual gendisks
131 * as member "struct gendisk *vdisk;"
133 struct drbd_conf **minor_table;
135 struct kmem_cache *drbd_request_cache;
136 struct kmem_cache *drbd_ee_cache; /* epoch entries */
137 struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */
138 struct kmem_cache *drbd_al_ext_cache; /* activity log extents */
139 mempool_t *drbd_request_mempool;
140 mempool_t *drbd_ee_mempool;
142 /* I do not use a standard mempool, because:
143 1) I want to hand out the pre-allocated objects first.
144 2) I want to be able to interrupt sleeping allocation with a signal.
145 Note: This is a single linked list, the next pointer is the private
146 member of struct page.
148 struct page *drbd_pp_pool;
149 spinlock_t drbd_pp_lock;
151 wait_queue_head_t drbd_pp_wait;
153 DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5);
155 static const struct block_device_operations drbd_ops = {
156 .owner = THIS_MODULE,
158 .release = drbd_release,
161 #define ARRY_SIZE(A) (sizeof(A)/sizeof(A[0]))
164 /* When checking with sparse, and this is an inline function, sparse will
165 give tons of false positives. When this is a real functions sparse works.
167 int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
171 atomic_inc(&mdev->local_cnt);
172 io_allowed = (mdev->state.disk >= mins);
174 if (atomic_dec_and_test(&mdev->local_cnt))
175 wake_up(&mdev->misc_wait);
183 * DOC: The transfer log
185 * The transfer log is a single linked list of &struct drbd_tl_epoch objects.
186 * mdev->newest_tle points to the head, mdev->oldest_tle points to the tail
187 * of the list. There is always at least one &struct drbd_tl_epoch object.
189 * Each &struct drbd_tl_epoch has a circular double linked list of requests
192 static int tl_init(struct drbd_conf *mdev)
194 struct drbd_tl_epoch *b;
196 /* during device minor initialization, we may well use GFP_KERNEL */
197 b = kmalloc(sizeof(struct drbd_tl_epoch), GFP_KERNEL);
200 INIT_LIST_HEAD(&b->requests);
201 INIT_LIST_HEAD(&b->w.list);
205 b->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
207 mdev->oldest_tle = b;
208 mdev->newest_tle = b;
209 INIT_LIST_HEAD(&mdev->out_of_sequence_requests);
211 mdev->tl_hash = NULL;
217 static void tl_cleanup(struct drbd_conf *mdev)
219 D_ASSERT(mdev->oldest_tle == mdev->newest_tle);
220 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
221 kfree(mdev->oldest_tle);
222 mdev->oldest_tle = NULL;
223 kfree(mdev->unused_spare_tle);
224 mdev->unused_spare_tle = NULL;
225 kfree(mdev->tl_hash);
226 mdev->tl_hash = NULL;
231 * _tl_add_barrier() - Adds a barrier to the transfer log
232 * @mdev: DRBD device.
233 * @new: Barrier to be added before the current head of the TL.
235 * The caller must hold the req_lock.
237 void _tl_add_barrier(struct drbd_conf *mdev, struct drbd_tl_epoch *new)
239 struct drbd_tl_epoch *newest_before;
241 INIT_LIST_HEAD(&new->requests);
242 INIT_LIST_HEAD(&new->w.list);
243 new->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
247 newest_before = mdev->newest_tle;
248 /* never send a barrier number == 0, because that is special-cased
249 * when using TCQ for our write ordering code */
250 new->br_number = (newest_before->br_number+1) ?: 1;
251 if (mdev->newest_tle != new) {
252 mdev->newest_tle->next = new;
253 mdev->newest_tle = new;
258 * tl_release() - Free or recycle the oldest &struct drbd_tl_epoch object of the TL
259 * @mdev: DRBD device.
260 * @barrier_nr: Expected identifier of the DRBD write barrier packet.
261 * @set_size: Expected number of requests before that barrier.
263 * In case the passed barrier_nr or set_size does not match the oldest
264 * &struct drbd_tl_epoch objects this function will cause a termination
267 void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
268 unsigned int set_size)
270 struct drbd_tl_epoch *b, *nob; /* next old barrier */
271 struct list_head *le, *tle;
272 struct drbd_request *r;
274 spin_lock_irq(&mdev->req_lock);
276 b = mdev->oldest_tle;
278 /* first some paranoia code */
280 dev_err(DEV, "BAD! BarrierAck #%u received, but no epoch in tl!?\n",
284 if (b->br_number != barrier_nr) {
285 dev_err(DEV, "BAD! BarrierAck #%u received, expected #%u!\n",
286 barrier_nr, b->br_number);
289 if (b->n_writes != set_size) {
290 dev_err(DEV, "BAD! BarrierAck #%u received with n_writes=%u, expected n_writes=%u!\n",
291 barrier_nr, set_size, b->n_writes);
295 /* Clean up list of requests processed during current epoch */
296 list_for_each_safe(le, tle, &b->requests) {
297 r = list_entry(le, struct drbd_request, tl_requests);
298 _req_mod(r, barrier_acked);
300 /* There could be requests on the list waiting for completion
301 of the write to the local disk. To avoid corruptions of
302 slab's data structures we have to remove the lists head.
304 Also there could have been a barrier ack out of sequence, overtaking
305 the write acks - which would be a bug and violating write ordering.
306 To not deadlock in case we lose connection while such requests are
307 still pending, we need some way to find them for the
308 _req_mode(connection_lost_while_pending).
310 These have been list_move'd to the out_of_sequence_requests list in
311 _req_mod(, barrier_acked) above.
313 list_del_init(&b->requests);
316 if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags)) {
317 _tl_add_barrier(mdev, b);
319 mdev->oldest_tle = nob;
320 /* if nob == NULL b was the only barrier, and becomes the new
321 barrier. Therefore mdev->oldest_tle points already to b */
323 D_ASSERT(nob != NULL);
324 mdev->oldest_tle = nob;
328 spin_unlock_irq(&mdev->req_lock);
329 dec_ap_pending(mdev);
334 spin_unlock_irq(&mdev->req_lock);
335 drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
339 * _tl_restart() - Walks the transfer log, and applies an action to all requests
340 * @mdev: DRBD device.
341 * @what: The action/event to perform with all request objects
343 * @what might be one of connection_lost_while_pending, resend, fail_frozen_disk_io,
344 * restart_frozen_disk_io.
346 static void _tl_restart(struct drbd_conf *mdev, enum drbd_req_event what)
348 struct drbd_tl_epoch *b, *tmp, **pn;
349 struct list_head *le, *tle, carry_reads;
350 struct drbd_request *req;
351 int rv, n_writes, n_reads;
353 b = mdev->oldest_tle;
354 pn = &mdev->oldest_tle;
358 INIT_LIST_HEAD(&carry_reads);
359 list_for_each_safe(le, tle, &b->requests) {
360 req = list_entry(le, struct drbd_request, tl_requests);
361 rv = _req_mod(req, what);
363 n_writes += (rv & MR_WRITE) >> MR_WRITE_SHIFT;
364 n_reads += (rv & MR_READ) >> MR_READ_SHIFT;
369 if (what == resend) {
370 b->n_writes = n_writes;
371 if (b->w.cb == NULL) {
372 b->w.cb = w_send_barrier;
373 inc_ap_pending(mdev);
374 set_bit(CREATE_BARRIER, &mdev->flags);
377 drbd_queue_work(&mdev->data.work, &b->w);
382 list_add(&carry_reads, &b->requests);
383 /* there could still be requests on that ring list,
384 * in case local io is still pending */
385 list_del(&b->requests);
387 /* dec_ap_pending corresponding to queue_barrier.
388 * the newest barrier may not have been queued yet,
389 * in which case w.cb is still NULL. */
391 dec_ap_pending(mdev);
393 if (b == mdev->newest_tle) {
394 /* recycle, but reinit! */
395 D_ASSERT(tmp == NULL);
396 INIT_LIST_HEAD(&b->requests);
397 list_splice(&carry_reads, &b->requests);
398 INIT_LIST_HEAD(&b->w.list);
400 b->br_number = net_random();
410 list_splice(&carry_reads, &b->requests);
416 * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL
417 * @mdev: DRBD device.
419 * This is called after the connection to the peer was lost. The storage covered
420 * by the requests on the transfer gets marked as our of sync. Called from the
421 * receiver thread and the worker thread.
423 void tl_clear(struct drbd_conf *mdev)
425 struct list_head *le, *tle;
426 struct drbd_request *r;
428 spin_lock_irq(&mdev->req_lock);
430 _tl_restart(mdev, connection_lost_while_pending);
432 /* we expect this list to be empty. */
433 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
435 /* but just in case, clean it up anyways! */
436 list_for_each_safe(le, tle, &mdev->out_of_sequence_requests) {
437 r = list_entry(le, struct drbd_request, tl_requests);
438 /* It would be nice to complete outside of spinlock.
439 * But this is easier for now. */
440 _req_mod(r, connection_lost_while_pending);
443 /* ensure bit indicating barrier is required is clear */
444 clear_bit(CREATE_BARRIER, &mdev->flags);
446 memset(mdev->app_reads_hash, 0, APP_R_HSIZE*sizeof(void *));
448 spin_unlock_irq(&mdev->req_lock);
451 void tl_restart(struct drbd_conf *mdev, enum drbd_req_event what)
453 spin_lock_irq(&mdev->req_lock);
454 _tl_restart(mdev, what);
455 spin_unlock_irq(&mdev->req_lock);
459 * cl_wide_st_chg() - true if the state change is a cluster wide one
460 * @mdev: DRBD device.
461 * @os: old (current) state.
462 * @ns: new (wanted) state.
464 static int cl_wide_st_chg(struct drbd_conf *mdev,
465 union drbd_state os, union drbd_state ns)
467 return (os.conn >= C_CONNECTED && ns.conn >= C_CONNECTED &&
468 ((os.role != R_PRIMARY && ns.role == R_PRIMARY) ||
469 (os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
470 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S) ||
471 (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))) ||
472 (os.conn >= C_CONNECTED && ns.conn == C_DISCONNECTING) ||
473 (os.conn == C_CONNECTED && ns.conn == C_VERIFY_S);
477 drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f,
478 union drbd_state mask, union drbd_state val)
481 union drbd_state os, ns;
482 enum drbd_state_rv rv;
484 spin_lock_irqsave(&mdev->req_lock, flags);
486 ns.i = (os.i & ~mask.i) | val.i;
487 rv = _drbd_set_state(mdev, ns, f, NULL);
489 spin_unlock_irqrestore(&mdev->req_lock, flags);
495 * drbd_force_state() - Impose a change which happens outside our control on our state
496 * @mdev: DRBD device.
497 * @mask: mask of state bits to change.
498 * @val: value of new state bits.
500 void drbd_force_state(struct drbd_conf *mdev,
501 union drbd_state mask, union drbd_state val)
503 drbd_change_state(mdev, CS_HARD, mask, val);
506 static enum drbd_state_rv is_valid_state(struct drbd_conf *, union drbd_state);
507 static enum drbd_state_rv is_valid_state_transition(struct drbd_conf *,
510 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
511 union drbd_state ns, const char **warn_sync_abort);
512 int drbd_send_state_req(struct drbd_conf *,
513 union drbd_state, union drbd_state);
515 static enum drbd_state_rv
516 _req_st_cond(struct drbd_conf *mdev, union drbd_state mask,
517 union drbd_state val)
519 union drbd_state os, ns;
521 enum drbd_state_rv rv;
523 if (test_and_clear_bit(CL_ST_CHG_SUCCESS, &mdev->flags))
524 return SS_CW_SUCCESS;
526 if (test_and_clear_bit(CL_ST_CHG_FAIL, &mdev->flags))
527 return SS_CW_FAILED_BY_PEER;
530 spin_lock_irqsave(&mdev->req_lock, flags);
532 ns.i = (os.i & ~mask.i) | val.i;
533 ns = sanitize_state(mdev, os, ns, NULL);
535 if (!cl_wide_st_chg(mdev, os, ns))
538 rv = is_valid_state(mdev, ns);
539 if (rv == SS_SUCCESS) {
540 rv = is_valid_state_transition(mdev, ns, os);
541 if (rv == SS_SUCCESS)
542 rv = SS_UNKNOWN_ERROR; /* cont waiting, otherwise fail. */
545 spin_unlock_irqrestore(&mdev->req_lock, flags);
551 * drbd_req_state() - Perform an eventually cluster wide state change
552 * @mdev: DRBD device.
553 * @mask: mask of state bits to change.
554 * @val: value of new state bits.
557 * Should not be called directly, use drbd_request_state() or
558 * _drbd_request_state().
560 static enum drbd_state_rv
561 drbd_req_state(struct drbd_conf *mdev, union drbd_state mask,
562 union drbd_state val, enum chg_state_flags f)
564 struct completion done;
566 union drbd_state os, ns;
567 enum drbd_state_rv rv;
569 init_completion(&done);
571 if (f & CS_SERIALIZE)
572 mutex_lock(&mdev->state_mutex);
574 spin_lock_irqsave(&mdev->req_lock, flags);
576 ns.i = (os.i & ~mask.i) | val.i;
577 ns = sanitize_state(mdev, os, ns, NULL);
579 if (cl_wide_st_chg(mdev, os, ns)) {
580 rv = is_valid_state(mdev, ns);
581 if (rv == SS_SUCCESS)
582 rv = is_valid_state_transition(mdev, ns, os);
583 spin_unlock_irqrestore(&mdev->req_lock, flags);
585 if (rv < SS_SUCCESS) {
587 print_st_err(mdev, os, ns, rv);
591 drbd_state_lock(mdev);
592 if (!drbd_send_state_req(mdev, mask, val)) {
593 drbd_state_unlock(mdev);
594 rv = SS_CW_FAILED_BY_PEER;
596 print_st_err(mdev, os, ns, rv);
600 wait_event(mdev->state_wait,
601 (rv = _req_st_cond(mdev, mask, val)));
603 if (rv < SS_SUCCESS) {
604 drbd_state_unlock(mdev);
606 print_st_err(mdev, os, ns, rv);
609 spin_lock_irqsave(&mdev->req_lock, flags);
611 ns.i = (os.i & ~mask.i) | val.i;
612 rv = _drbd_set_state(mdev, ns, f, &done);
613 drbd_state_unlock(mdev);
615 rv = _drbd_set_state(mdev, ns, f, &done);
618 spin_unlock_irqrestore(&mdev->req_lock, flags);
620 if (f & CS_WAIT_COMPLETE && rv == SS_SUCCESS) {
621 D_ASSERT(current != mdev->worker.task);
622 wait_for_completion(&done);
626 if (f & CS_SERIALIZE)
627 mutex_unlock(&mdev->state_mutex);
633 * _drbd_request_state() - Request a state change (with flags)
634 * @mdev: DRBD device.
635 * @mask: mask of state bits to change.
636 * @val: value of new state bits.
639 * Cousin of drbd_request_state(), useful with the CS_WAIT_COMPLETE
640 * flag, or when logging of failed state change requests is not desired.
643 _drbd_request_state(struct drbd_conf *mdev, union drbd_state mask,
644 union drbd_state val, enum chg_state_flags f)
646 enum drbd_state_rv rv;
648 wait_event(mdev->state_wait,
649 (rv = drbd_req_state(mdev, mask, val, f)) != SS_IN_TRANSIENT_STATE);
654 static void print_st(struct drbd_conf *mdev, char *name, union drbd_state ns)
656 dev_err(DEV, " %s = { cs:%s ro:%s/%s ds:%s/%s %c%c%c%c }\n",
658 drbd_conn_str(ns.conn),
659 drbd_role_str(ns.role),
660 drbd_role_str(ns.peer),
661 drbd_disk_str(ns.disk),
662 drbd_disk_str(ns.pdsk),
663 is_susp(ns) ? 's' : 'r',
664 ns.aftr_isp ? 'a' : '-',
665 ns.peer_isp ? 'p' : '-',
666 ns.user_isp ? 'u' : '-'
670 void print_st_err(struct drbd_conf *mdev, union drbd_state os,
671 union drbd_state ns, enum drbd_state_rv err)
673 if (err == SS_IN_TRANSIENT_STATE)
675 dev_err(DEV, "State change failed: %s\n", drbd_set_st_err_str(err));
676 print_st(mdev, " state", os);
677 print_st(mdev, "wanted", ns);
682 * is_valid_state() - Returns an SS_ error code if ns is not valid
683 * @mdev: DRBD device.
684 * @ns: State to consider.
686 static enum drbd_state_rv
687 is_valid_state(struct drbd_conf *mdev, union drbd_state ns)
689 /* See drbd_state_sw_errors in drbd_strings.c */
691 enum drbd_fencing_p fp;
692 enum drbd_state_rv rv = SS_SUCCESS;
695 if (get_ldev(mdev)) {
696 fp = mdev->ldev->dc.fencing;
700 if (get_net_conf(mdev)) {
701 if (!mdev->net_conf->two_primaries &&
702 ns.role == R_PRIMARY && ns.peer == R_PRIMARY)
703 rv = SS_TWO_PRIMARIES;
708 /* already found a reason to abort */;
709 else if (ns.role == R_SECONDARY && mdev->open_cnt)
710 rv = SS_DEVICE_IN_USE;
712 else if (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.disk < D_UP_TO_DATE)
713 rv = SS_NO_UP_TO_DATE_DISK;
715 else if (fp >= FP_RESOURCE &&
716 ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk >= D_UNKNOWN)
719 else if (ns.role == R_PRIMARY && ns.disk <= D_INCONSISTENT && ns.pdsk <= D_INCONSISTENT)
720 rv = SS_NO_UP_TO_DATE_DISK;
722 else if (ns.conn > C_CONNECTED && ns.disk < D_INCONSISTENT)
723 rv = SS_NO_LOCAL_DISK;
725 else if (ns.conn > C_CONNECTED && ns.pdsk < D_INCONSISTENT)
726 rv = SS_NO_REMOTE_DISK;
728 else if (ns.conn > C_CONNECTED && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE)
729 rv = SS_NO_UP_TO_DATE_DISK;
731 else if ((ns.conn == C_CONNECTED ||
732 ns.conn == C_WF_BITMAP_S ||
733 ns.conn == C_SYNC_SOURCE ||
734 ns.conn == C_PAUSED_SYNC_S) &&
735 ns.disk == D_OUTDATED)
736 rv = SS_CONNECTED_OUTDATES;
738 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
739 (mdev->sync_conf.verify_alg[0] == 0))
740 rv = SS_NO_VERIFY_ALG;
742 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
743 mdev->agreed_pro_version < 88)
744 rv = SS_NOT_SUPPORTED;
750 * is_valid_state_transition() - Returns an SS_ error code if the state transition is not possible
751 * @mdev: DRBD device.
755 static enum drbd_state_rv
756 is_valid_state_transition(struct drbd_conf *mdev, union drbd_state ns,
759 enum drbd_state_rv rv = SS_SUCCESS;
761 if ((ns.conn == C_STARTING_SYNC_T || ns.conn == C_STARTING_SYNC_S) &&
762 os.conn > C_CONNECTED)
763 rv = SS_RESYNC_RUNNING;
765 if (ns.conn == C_DISCONNECTING && os.conn == C_STANDALONE)
766 rv = SS_ALREADY_STANDALONE;
768 if (ns.disk > D_ATTACHING && os.disk == D_DISKLESS)
771 if (ns.conn == C_WF_CONNECTION && os.conn < C_UNCONNECTED)
772 rv = SS_NO_NET_CONFIG;
774 if (ns.disk == D_OUTDATED && os.disk < D_OUTDATED && os.disk != D_ATTACHING)
775 rv = SS_LOWER_THAN_OUTDATED;
777 if (ns.conn == C_DISCONNECTING && os.conn == C_UNCONNECTED)
778 rv = SS_IN_TRANSIENT_STATE;
780 if (ns.conn == os.conn && ns.conn == C_WF_REPORT_PARAMS)
781 rv = SS_IN_TRANSIENT_STATE;
783 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && os.conn < C_CONNECTED)
784 rv = SS_NEED_CONNECTION;
786 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
787 ns.conn != os.conn && os.conn > C_CONNECTED)
788 rv = SS_RESYNC_RUNNING;
790 if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) &&
791 os.conn < C_CONNECTED)
792 rv = SS_NEED_CONNECTION;
794 if ((ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)
795 && os.conn < C_WF_REPORT_PARAMS)
796 rv = SS_NEED_CONNECTION; /* No NetworkFailure -> SyncTarget etc... */
802 * sanitize_state() - Resolves implicitly necessary additional changes to a state transition
803 * @mdev: DRBD device.
808 * When we loose connection, we have to set the state of the peers disk (pdsk)
809 * to D_UNKNOWN. This rule and many more along those lines are in this function.
811 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
812 union drbd_state ns, const char **warn_sync_abort)
814 enum drbd_fencing_p fp;
815 enum drbd_disk_state disk_min, disk_max, pdsk_min, pdsk_max;
818 if (get_ldev(mdev)) {
819 fp = mdev->ldev->dc.fencing;
823 /* Disallow Network errors to configure a device's network part */
824 if ((ns.conn >= C_TIMEOUT && ns.conn <= C_TEAR_DOWN) &&
825 os.conn <= C_DISCONNECTING)
828 /* After a network error (+C_TEAR_DOWN) only C_UNCONNECTED or C_DISCONNECTING can follow.
829 * If you try to go into some Sync* state, that shall fail (elsewhere). */
830 if (os.conn >= C_TIMEOUT && os.conn <= C_TEAR_DOWN &&
831 ns.conn != C_UNCONNECTED && ns.conn != C_DISCONNECTING && ns.conn <= C_TEAR_DOWN)
834 /* we cannot fail (again) if we already detached */
835 if (ns.disk == D_FAILED && os.disk == D_DISKLESS)
836 ns.disk = D_DISKLESS;
838 /* if we are only D_ATTACHING yet,
839 * we can (and should) go directly to D_DISKLESS. */
840 if (ns.disk == D_FAILED && os.disk == D_ATTACHING)
841 ns.disk = D_DISKLESS;
843 /* After C_DISCONNECTING only C_STANDALONE may follow */
844 if (os.conn == C_DISCONNECTING && ns.conn != C_STANDALONE)
847 if (ns.conn < C_CONNECTED) {
850 if (ns.pdsk > D_UNKNOWN || ns.pdsk < D_INCONSISTENT)
854 /* Clear the aftr_isp when becoming unconfigured */
855 if (ns.conn == C_STANDALONE && ns.disk == D_DISKLESS && ns.role == R_SECONDARY)
858 /* Abort resync if a disk fails/detaches */
859 if (os.conn > C_CONNECTED && ns.conn > C_CONNECTED &&
860 (ns.disk <= D_FAILED || ns.pdsk <= D_FAILED)) {
863 os.conn == C_VERIFY_S || os.conn == C_VERIFY_T ?
864 "Online-verify" : "Resync";
865 ns.conn = C_CONNECTED;
868 /* Connection breaks down before we finished "Negotiating" */
869 if (ns.conn < C_CONNECTED && ns.disk == D_NEGOTIATING &&
870 get_ldev_if_state(mdev, D_NEGOTIATING)) {
871 if (mdev->ed_uuid == mdev->ldev->md.uuid[UI_CURRENT]) {
872 ns.disk = mdev->new_state_tmp.disk;
873 ns.pdsk = mdev->new_state_tmp.pdsk;
875 dev_alert(DEV, "Connection lost while negotiating, no data!\n");
876 ns.disk = D_DISKLESS;
882 /* D_CONSISTENT and D_OUTDATED vanish when we get connected */
883 if (ns.conn >= C_CONNECTED && ns.conn < C_AHEAD) {
884 if (ns.disk == D_CONSISTENT || ns.disk == D_OUTDATED)
885 ns.disk = D_UP_TO_DATE;
886 if (ns.pdsk == D_CONSISTENT || ns.pdsk == D_OUTDATED)
887 ns.pdsk = D_UP_TO_DATE;
890 /* Implications of the connection stat on the disk states */
891 disk_min = D_DISKLESS;
892 disk_max = D_UP_TO_DATE;
893 pdsk_min = D_INCONSISTENT;
894 pdsk_max = D_UNKNOWN;
895 switch ((enum drbd_conns)ns.conn) {
897 case C_PAUSED_SYNC_T:
898 case C_STARTING_SYNC_T:
901 disk_min = D_INCONSISTENT;
902 disk_max = D_OUTDATED;
903 pdsk_min = D_UP_TO_DATE;
904 pdsk_max = D_UP_TO_DATE;
908 disk_min = D_UP_TO_DATE;
909 disk_max = D_UP_TO_DATE;
910 pdsk_min = D_UP_TO_DATE;
911 pdsk_max = D_UP_TO_DATE;
914 disk_min = D_DISKLESS;
915 disk_max = D_UP_TO_DATE;
916 pdsk_min = D_DISKLESS;
917 pdsk_max = D_UP_TO_DATE;
920 case C_PAUSED_SYNC_S:
921 case C_STARTING_SYNC_S:
923 disk_min = D_UP_TO_DATE;
924 disk_max = D_UP_TO_DATE;
925 pdsk_min = D_INCONSISTENT;
926 pdsk_max = D_CONSISTENT; /* D_OUTDATED would be nice. But explicit outdate necessary*/
929 disk_min = D_INCONSISTENT;
930 disk_max = D_INCONSISTENT;
931 pdsk_min = D_UP_TO_DATE;
932 pdsk_max = D_UP_TO_DATE;
935 disk_min = D_UP_TO_DATE;
936 disk_max = D_UP_TO_DATE;
937 pdsk_min = D_INCONSISTENT;
938 pdsk_max = D_INCONSISTENT;
941 case C_DISCONNECTING:
945 case C_NETWORK_FAILURE:
946 case C_PROTOCOL_ERROR:
948 case C_WF_CONNECTION:
949 case C_WF_REPORT_PARAMS:
953 if (ns.disk > disk_max)
956 if (ns.disk < disk_min) {
957 dev_warn(DEV, "Implicitly set disk from %s to %s\n",
958 drbd_disk_str(ns.disk), drbd_disk_str(disk_min));
961 if (ns.pdsk > pdsk_max)
964 if (ns.pdsk < pdsk_min) {
965 dev_warn(DEV, "Implicitly set pdsk from %s to %s\n",
966 drbd_disk_str(ns.pdsk), drbd_disk_str(pdsk_min));
970 if (fp == FP_STONITH &&
971 (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk > D_OUTDATED) &&
972 !(os.role == R_PRIMARY && os.conn < C_CONNECTED && os.pdsk > D_OUTDATED))
973 ns.susp_fen = 1; /* Suspend IO while fence-peer handler runs (peer lost) */
975 if (mdev->sync_conf.on_no_data == OND_SUSPEND_IO &&
976 (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE) &&
977 !(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE))
978 ns.susp_nod = 1; /* Suspend IO while no data available (no accessible data available) */
980 if (ns.aftr_isp || ns.peer_isp || ns.user_isp) {
981 if (ns.conn == C_SYNC_SOURCE)
982 ns.conn = C_PAUSED_SYNC_S;
983 if (ns.conn == C_SYNC_TARGET)
984 ns.conn = C_PAUSED_SYNC_T;
986 if (ns.conn == C_PAUSED_SYNC_S)
987 ns.conn = C_SYNC_SOURCE;
988 if (ns.conn == C_PAUSED_SYNC_T)
989 ns.conn = C_SYNC_TARGET;
995 /* helper for __drbd_set_state */
996 static void set_ov_position(struct drbd_conf *mdev, enum drbd_conns cs)
998 if (mdev->agreed_pro_version < 90)
999 mdev->ov_start_sector = 0;
1000 mdev->rs_total = drbd_bm_bits(mdev);
1001 mdev->ov_position = 0;
1002 if (cs == C_VERIFY_T) {
1003 /* starting online verify from an arbitrary position
1004 * does not fit well into the existing protocol.
1005 * on C_VERIFY_T, we initialize ov_left and friends
1006 * implicitly in receive_DataRequest once the
1007 * first P_OV_REQUEST is received */
1008 mdev->ov_start_sector = ~(sector_t)0;
1010 unsigned long bit = BM_SECT_TO_BIT(mdev->ov_start_sector);
1011 if (bit >= mdev->rs_total) {
1012 mdev->ov_start_sector =
1013 BM_BIT_TO_SECT(mdev->rs_total - 1);
1016 mdev->rs_total -= bit;
1017 mdev->ov_position = mdev->ov_start_sector;
1019 mdev->ov_left = mdev->rs_total;
1022 static void drbd_resume_al(struct drbd_conf *mdev)
1024 if (test_and_clear_bit(AL_SUSPENDED, &mdev->flags))
1025 dev_info(DEV, "Resumed AL updates\n");
1029 * __drbd_set_state() - Set a new DRBD state
1030 * @mdev: DRBD device.
1033 * @done: Optional completion, that will get completed after the after_state_ch() finished
1035 * Caller needs to hold req_lock, and global_state_lock. Do not call directly.
1038 __drbd_set_state(struct drbd_conf *mdev, union drbd_state ns,
1039 enum chg_state_flags flags, struct completion *done)
1041 union drbd_state os;
1042 enum drbd_state_rv rv = SS_SUCCESS;
1043 const char *warn_sync_abort = NULL;
1044 struct after_state_chg_work *ascw;
1048 ns = sanitize_state(mdev, os, ns, &warn_sync_abort);
1051 return SS_NOTHING_TO_DO;
1053 if (!(flags & CS_HARD)) {
1054 /* pre-state-change checks ; only look at ns */
1055 /* See drbd_state_sw_errors in drbd_strings.c */
1057 rv = is_valid_state(mdev, ns);
1058 if (rv < SS_SUCCESS) {
1059 /* If the old state was illegal as well, then let
1062 if (is_valid_state(mdev, os) == rv)
1063 rv = is_valid_state_transition(mdev, ns, os);
1065 rv = is_valid_state_transition(mdev, ns, os);
1068 if (rv < SS_SUCCESS) {
1069 if (flags & CS_VERBOSE)
1070 print_st_err(mdev, os, ns, rv);
1074 if (warn_sync_abort)
1075 dev_warn(DEV, "%s aborted.\n", warn_sync_abort);
1081 if (ns.role != os.role)
1082 pbp += sprintf(pbp, "role( %s -> %s ) ",
1083 drbd_role_str(os.role),
1084 drbd_role_str(ns.role));
1085 if (ns.peer != os.peer)
1086 pbp += sprintf(pbp, "peer( %s -> %s ) ",
1087 drbd_role_str(os.peer),
1088 drbd_role_str(ns.peer));
1089 if (ns.conn != os.conn)
1090 pbp += sprintf(pbp, "conn( %s -> %s ) ",
1091 drbd_conn_str(os.conn),
1092 drbd_conn_str(ns.conn));
1093 if (ns.disk != os.disk)
1094 pbp += sprintf(pbp, "disk( %s -> %s ) ",
1095 drbd_disk_str(os.disk),
1096 drbd_disk_str(ns.disk));
1097 if (ns.pdsk != os.pdsk)
1098 pbp += sprintf(pbp, "pdsk( %s -> %s ) ",
1099 drbd_disk_str(os.pdsk),
1100 drbd_disk_str(ns.pdsk));
1101 if (is_susp(ns) != is_susp(os))
1102 pbp += sprintf(pbp, "susp( %d -> %d ) ",
1105 if (ns.aftr_isp != os.aftr_isp)
1106 pbp += sprintf(pbp, "aftr_isp( %d -> %d ) ",
1109 if (ns.peer_isp != os.peer_isp)
1110 pbp += sprintf(pbp, "peer_isp( %d -> %d ) ",
1113 if (ns.user_isp != os.user_isp)
1114 pbp += sprintf(pbp, "user_isp( %d -> %d ) ",
1117 dev_info(DEV, "%s\n", pb);
1120 /* solve the race between becoming unconfigured,
1121 * worker doing the cleanup, and
1122 * admin reconfiguring us:
1123 * on (re)configure, first set CONFIG_PENDING,
1124 * then wait for a potentially exiting worker,
1125 * start the worker, and schedule one no_op.
1126 * then proceed with configuration.
1128 if (ns.disk == D_DISKLESS &&
1129 ns.conn == C_STANDALONE &&
1130 ns.role == R_SECONDARY &&
1131 !test_and_set_bit(CONFIG_PENDING, &mdev->flags))
1132 set_bit(DEVICE_DYING, &mdev->flags);
1134 /* if we are going -> D_FAILED or D_DISKLESS, grab one extra reference
1135 * on the ldev here, to be sure the transition -> D_DISKLESS resp.
1136 * drbd_ldev_destroy() won't happen before our corresponding
1137 * after_state_ch works run, where we put_ldev again. */
1138 if ((os.disk != D_FAILED && ns.disk == D_FAILED) ||
1139 (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))
1140 atomic_inc(&mdev->local_cnt);
1143 wake_up(&mdev->misc_wait);
1144 wake_up(&mdev->state_wait);
1146 /* aborted verify run. log the last position */
1147 if ((os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) &&
1148 ns.conn < C_CONNECTED) {
1149 mdev->ov_start_sector =
1150 BM_BIT_TO_SECT(drbd_bm_bits(mdev) - mdev->ov_left);
1151 dev_info(DEV, "Online Verify reached sector %llu\n",
1152 (unsigned long long)mdev->ov_start_sector);
1155 if ((os.conn == C_PAUSED_SYNC_T || os.conn == C_PAUSED_SYNC_S) &&
1156 (ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)) {
1157 dev_info(DEV, "Syncer continues.\n");
1158 mdev->rs_paused += (long)jiffies
1159 -(long)mdev->rs_mark_time[mdev->rs_last_mark];
1160 if (ns.conn == C_SYNC_TARGET)
1161 mod_timer(&mdev->resync_timer, jiffies);
1164 if ((os.conn == C_SYNC_TARGET || os.conn == C_SYNC_SOURCE) &&
1165 (ns.conn == C_PAUSED_SYNC_T || ns.conn == C_PAUSED_SYNC_S)) {
1166 dev_info(DEV, "Resync suspended\n");
1167 mdev->rs_mark_time[mdev->rs_last_mark] = jiffies;
1170 if (os.conn == C_CONNECTED &&
1171 (ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T)) {
1172 unsigned long now = jiffies;
1175 set_ov_position(mdev, ns.conn);
1176 mdev->rs_start = now;
1177 mdev->rs_last_events = 0;
1178 mdev->rs_last_sect_ev = 0;
1179 mdev->ov_last_oos_size = 0;
1180 mdev->ov_last_oos_start = 0;
1182 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
1183 mdev->rs_mark_left[i] = mdev->ov_left;
1184 mdev->rs_mark_time[i] = now;
1187 drbd_rs_controller_reset(mdev);
1189 if (ns.conn == C_VERIFY_S) {
1190 dev_info(DEV, "Starting Online Verify from sector %llu\n",
1191 (unsigned long long)mdev->ov_position);
1192 mod_timer(&mdev->resync_timer, jiffies);
1196 if (get_ldev(mdev)) {
1197 u32 mdf = mdev->ldev->md.flags & ~(MDF_CONSISTENT|MDF_PRIMARY_IND|
1198 MDF_CONNECTED_IND|MDF_WAS_UP_TO_DATE|
1199 MDF_PEER_OUT_DATED|MDF_CRASHED_PRIMARY);
1201 if (test_bit(CRASHED_PRIMARY, &mdev->flags))
1202 mdf |= MDF_CRASHED_PRIMARY;
1203 if (mdev->state.role == R_PRIMARY ||
1204 (mdev->state.pdsk < D_INCONSISTENT && mdev->state.peer == R_PRIMARY))
1205 mdf |= MDF_PRIMARY_IND;
1206 if (mdev->state.conn > C_WF_REPORT_PARAMS)
1207 mdf |= MDF_CONNECTED_IND;
1208 if (mdev->state.disk > D_INCONSISTENT)
1209 mdf |= MDF_CONSISTENT;
1210 if (mdev->state.disk > D_OUTDATED)
1211 mdf |= MDF_WAS_UP_TO_DATE;
1212 if (mdev->state.pdsk <= D_OUTDATED && mdev->state.pdsk >= D_INCONSISTENT)
1213 mdf |= MDF_PEER_OUT_DATED;
1214 if (mdf != mdev->ldev->md.flags) {
1215 mdev->ldev->md.flags = mdf;
1216 drbd_md_mark_dirty(mdev);
1218 if (os.disk < D_CONSISTENT && ns.disk >= D_CONSISTENT)
1219 drbd_set_ed_uuid(mdev, mdev->ldev->md.uuid[UI_CURRENT]);
1223 /* Peer was forced D_UP_TO_DATE & R_PRIMARY, consider to resync */
1224 if (os.disk == D_INCONSISTENT && os.pdsk == D_INCONSISTENT &&
1225 os.peer == R_SECONDARY && ns.peer == R_PRIMARY)
1226 set_bit(CONSIDER_RESYNC, &mdev->flags);
1228 /* Receiver should clean up itself */
1229 if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING)
1230 drbd_thread_stop_nowait(&mdev->receiver);
1232 /* Now the receiver finished cleaning up itself, it should die */
1233 if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE)
1234 drbd_thread_stop_nowait(&mdev->receiver);
1236 /* Upon network failure, we need to restart the receiver. */
1237 if (os.conn > C_TEAR_DOWN &&
1238 ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT)
1239 drbd_thread_restart_nowait(&mdev->receiver);
1241 /* Resume AL writing if we get a connection */
1242 if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)
1243 drbd_resume_al(mdev);
1245 ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC);
1249 ascw->flags = flags;
1250 ascw->w.cb = w_after_state_ch;
1252 drbd_queue_work(&mdev->data.work, &ascw->w);
1254 dev_warn(DEV, "Could not kmalloc an ascw\n");
1260 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused)
1262 struct after_state_chg_work *ascw =
1263 container_of(w, struct after_state_chg_work, w);
1264 after_state_ch(mdev, ascw->os, ascw->ns, ascw->flags);
1265 if (ascw->flags & CS_WAIT_COMPLETE) {
1266 D_ASSERT(ascw->done != NULL);
1267 complete(ascw->done);
1274 static void abw_start_sync(struct drbd_conf *mdev, int rv)
1277 dev_err(DEV, "Writing the bitmap failed not starting resync.\n");
1278 _drbd_request_state(mdev, NS(conn, C_CONNECTED), CS_VERBOSE);
1282 switch (mdev->state.conn) {
1283 case C_STARTING_SYNC_T:
1284 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE);
1286 case C_STARTING_SYNC_S:
1287 drbd_start_resync(mdev, C_SYNC_SOURCE);
1292 int drbd_bitmap_io_from_worker(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why)
1296 D_ASSERT(current == mdev->worker.task);
1298 /* open coded non-blocking drbd_suspend_io(mdev); */
1299 set_bit(SUSPEND_IO, &mdev->flags);
1300 if (!is_susp(mdev->state))
1301 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
1303 drbd_bm_lock(mdev, why);
1305 drbd_bm_unlock(mdev);
1307 drbd_resume_io(mdev);
1313 * after_state_ch() - Perform after state change actions that may sleep
1314 * @mdev: DRBD device.
1319 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
1320 union drbd_state ns, enum chg_state_flags flags)
1322 enum drbd_fencing_p fp;
1323 enum drbd_req_event what = nothing;
1324 union drbd_state nsm = (union drbd_state){ .i = -1 };
1326 if (os.conn != C_CONNECTED && ns.conn == C_CONNECTED) {
1327 clear_bit(CRASHED_PRIMARY, &mdev->flags);
1329 mdev->p_uuid[UI_FLAGS] &= ~((u64)2);
1333 if (get_ldev(mdev)) {
1334 fp = mdev->ldev->dc.fencing;
1338 /* Inform userspace about the change... */
1339 drbd_bcast_state(mdev, ns);
1341 if (!(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE) &&
1342 (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE))
1343 drbd_khelper(mdev, "pri-on-incon-degr");
1345 /* Here we have the actions that are performed after a
1346 state change. This function might sleep */
1350 if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED) {
1351 if (ns.conn == C_CONNECTED)
1352 what = resend, nsm.susp_nod = 0;
1353 else /* ns.conn > C_CONNECTED */
1354 dev_err(DEV, "Unexpected Resynd going on!\n");
1357 if (os.disk == D_ATTACHING && ns.disk > D_ATTACHING)
1358 what = restart_frozen_disk_io, nsm.susp_nod = 0;
1363 /* case1: The outdate peer handler is successful: */
1364 if (os.pdsk > D_OUTDATED && ns.pdsk <= D_OUTDATED) {
1366 if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
1367 drbd_uuid_new_current(mdev);
1368 clear_bit(NEW_CUR_UUID, &mdev->flags);
1370 spin_lock_irq(&mdev->req_lock);
1371 _drbd_set_state(_NS(mdev, susp_fen, 0), CS_VERBOSE, NULL);
1372 spin_unlock_irq(&mdev->req_lock);
1374 /* case2: The connection was established again: */
1375 if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED) {
1376 clear_bit(NEW_CUR_UUID, &mdev->flags);
1382 if (what != nothing) {
1383 spin_lock_irq(&mdev->req_lock);
1384 _tl_restart(mdev, what);
1385 nsm.i &= mdev->state.i;
1386 _drbd_set_state(mdev, nsm, CS_VERBOSE, NULL);
1387 spin_unlock_irq(&mdev->req_lock);
1390 /* Do not change the order of the if above and the two below... */
1391 if (os.pdsk == D_DISKLESS && ns.pdsk > D_DISKLESS) { /* attach on the peer */
1392 drbd_send_uuids(mdev);
1393 drbd_send_state(mdev);
1395 if (os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S)
1396 drbd_queue_bitmap_io(mdev, &drbd_send_bitmap, NULL, "send_bitmap (WFBitMapS)");
1398 /* Lost contact to peer's copy of the data */
1399 if ((os.pdsk >= D_INCONSISTENT &&
1400 os.pdsk != D_UNKNOWN &&
1401 os.pdsk != D_OUTDATED)
1402 && (ns.pdsk < D_INCONSISTENT ||
1403 ns.pdsk == D_UNKNOWN ||
1404 ns.pdsk == D_OUTDATED)) {
1405 if (get_ldev(mdev)) {
1406 if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) &&
1407 mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) {
1408 if (is_susp(mdev->state)) {
1409 set_bit(NEW_CUR_UUID, &mdev->flags);
1411 drbd_uuid_new_current(mdev);
1412 drbd_send_uuids(mdev);
1419 if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) {
1420 if (ns.peer == R_PRIMARY && mdev->ldev->md.uuid[UI_BITMAP] == 0) {
1421 drbd_uuid_new_current(mdev);
1422 drbd_send_uuids(mdev);
1425 /* D_DISKLESS Peer becomes secondary */
1426 if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
1427 drbd_bitmap_io_from_worker(mdev, &drbd_bm_write, "demote diskless peer");
1431 if (os.role == R_PRIMARY && ns.role == R_SECONDARY && get_ldev(mdev)) {
1432 drbd_bitmap_io_from_worker(mdev, &drbd_bm_write, "demote");
1436 /* Last part of the attaching process ... */
1437 if (ns.conn >= C_CONNECTED &&
1438 os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
1439 drbd_send_sizes(mdev, 0, 0); /* to start sync... */
1440 drbd_send_uuids(mdev);
1441 drbd_send_state(mdev);
1444 /* We want to pause/continue resync, tell peer. */
1445 if (ns.conn >= C_CONNECTED &&
1446 ((os.aftr_isp != ns.aftr_isp) ||
1447 (os.user_isp != ns.user_isp)))
1448 drbd_send_state(mdev);
1450 /* In case one of the isp bits got set, suspend other devices. */
1451 if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
1452 (ns.aftr_isp || ns.peer_isp || ns.user_isp))
1453 suspend_other_sg(mdev);
1455 /* Make sure the peer gets informed about eventual state
1456 changes (ISP bits) while we were in WFReportParams. */
1457 if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
1458 drbd_send_state(mdev);
1460 if (os.conn != C_AHEAD && ns.conn == C_AHEAD)
1461 drbd_send_state(mdev);
1463 /* We are in the progress to start a full sync... */
1464 if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
1465 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S))
1466 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, &abw_start_sync, "set_n_write from StartingSync");
1468 /* We are invalidating our self... */
1469 if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED &&
1470 os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT)
1471 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL, "set_n_write from invalidate");
1473 /* first half of local IO error, failure to attach,
1474 * or administrative detach */
1475 if (os.disk != D_FAILED && ns.disk == D_FAILED) {
1476 enum drbd_io_error_p eh;
1478 /* corresponding get_ldev was in __drbd_set_state, to serialize
1479 * our cleanup here with the transition to D_DISKLESS,
1480 * so it is safe to dreference ldev here. */
1481 eh = mdev->ldev->dc.on_io_error;
1482 was_io_error = test_and_clear_bit(WAS_IO_ERROR, &mdev->flags);
1484 /* current state still has to be D_FAILED,
1485 * there is only one way out: to D_DISKLESS,
1486 * and that may only happen after our put_ldev below. */
1487 if (mdev->state.disk != D_FAILED)
1489 "ASSERT FAILED: disk is %s during detach\n",
1490 drbd_disk_str(mdev->state.disk));
1492 if (drbd_send_state(mdev))
1493 dev_warn(DEV, "Notified peer that I am detaching my disk\n");
1495 dev_err(DEV, "Sending state for detaching disk failed\n");
1497 drbd_rs_cancel_all(mdev);
1499 /* In case we want to get something to stable storage still,
1500 * this may be the last chance.
1501 * Following put_ldev may transition to D_DISKLESS. */
1505 if (was_io_error && eh == EP_CALL_HELPER)
1506 drbd_khelper(mdev, "local-io-error");
1509 /* second half of local IO error, failure to attach,
1510 * or administrative detach,
1511 * after local_cnt references have reached zero again */
1512 if (os.disk != D_DISKLESS && ns.disk == D_DISKLESS) {
1513 /* We must still be diskless,
1514 * re-attach has to be serialized with this! */
1515 if (mdev->state.disk != D_DISKLESS)
1517 "ASSERT FAILED: disk is %s while going diskless\n",
1518 drbd_disk_str(mdev->state.disk));
1521 mdev->rs_failed = 0;
1522 atomic_set(&mdev->rs_pending_cnt, 0);
1524 if (drbd_send_state(mdev))
1525 dev_warn(DEV, "Notified peer that I'm now diskless.\n");
1527 dev_err(DEV, "Sending state for being diskless failed\n");
1528 /* corresponding get_ldev in __drbd_set_state
1529 * this may finaly trigger drbd_ldev_destroy. */
1533 /* Disks got bigger while they were detached */
1534 if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
1535 test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) {
1536 if (ns.conn == C_CONNECTED)
1537 resync_after_online_grow(mdev);
1540 /* A resync finished or aborted, wake paused devices... */
1541 if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) ||
1542 (os.peer_isp && !ns.peer_isp) ||
1543 (os.user_isp && !ns.user_isp))
1544 resume_next_sg(mdev);
1546 /* sync target done with resync. Explicitly notify peer, even though
1547 * it should (at least for non-empty resyncs) already know itself. */
1548 if (os.disk < D_UP_TO_DATE && os.conn >= C_SYNC_SOURCE && ns.conn == C_CONNECTED)
1549 drbd_send_state(mdev);
1551 if (os.conn > C_CONNECTED && ns.conn == C_CONNECTED)
1552 drbd_queue_bitmap_io(mdev, &drbd_bm_write, NULL, "write from resync_finished");
1554 /* free tl_hash if we Got thawed and are C_STANDALONE */
1555 if (ns.conn == C_STANDALONE && !is_susp(ns) && mdev->tl_hash)
1556 drbd_free_tl_hash(mdev);
1558 /* Upon network connection, we need to start the receiver */
1559 if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED)
1560 drbd_thread_start(&mdev->receiver);
1562 /* Terminate worker thread if we are unconfigured - it will be
1563 restarted as needed... */
1564 if (ns.disk == D_DISKLESS &&
1565 ns.conn == C_STANDALONE &&
1566 ns.role == R_SECONDARY) {
1567 if (os.aftr_isp != ns.aftr_isp)
1568 resume_next_sg(mdev);
1569 /* set in __drbd_set_state, unless CONFIG_PENDING was set */
1570 if (test_bit(DEVICE_DYING, &mdev->flags))
1571 drbd_thread_stop_nowait(&mdev->worker);
1578 static int drbd_thread_setup(void *arg)
1580 struct drbd_thread *thi = (struct drbd_thread *) arg;
1581 struct drbd_conf *mdev = thi->mdev;
1582 unsigned long flags;
1586 retval = thi->function(thi);
1588 spin_lock_irqsave(&thi->t_lock, flags);
1590 /* if the receiver has been "Exiting", the last thing it did
1591 * was set the conn state to "StandAlone",
1592 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
1593 * and receiver thread will be "started".
1594 * drbd_thread_start needs to set "Restarting" in that case.
1595 * t_state check and assignment needs to be within the same spinlock,
1596 * so either thread_start sees Exiting, and can remap to Restarting,
1597 * or thread_start see None, and can proceed as normal.
1600 if (thi->t_state == Restarting) {
1601 dev_info(DEV, "Restarting %s\n", current->comm);
1602 thi->t_state = Running;
1603 spin_unlock_irqrestore(&thi->t_lock, flags);
1608 thi->t_state = None;
1610 complete(&thi->stop);
1611 spin_unlock_irqrestore(&thi->t_lock, flags);
1613 dev_info(DEV, "Terminating %s\n", current->comm);
1615 /* Release mod reference taken when thread was started */
1616 module_put(THIS_MODULE);
1620 static void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi,
1621 int (*func) (struct drbd_thread *))
1623 spin_lock_init(&thi->t_lock);
1625 thi->t_state = None;
1626 thi->function = func;
1630 int drbd_thread_start(struct drbd_thread *thi)
1632 struct drbd_conf *mdev = thi->mdev;
1633 struct task_struct *nt;
1634 unsigned long flags;
1637 thi == &mdev->receiver ? "receiver" :
1638 thi == &mdev->asender ? "asender" :
1639 thi == &mdev->worker ? "worker" : "NONSENSE";
1641 /* is used from state engine doing drbd_thread_stop_nowait,
1642 * while holding the req lock irqsave */
1643 spin_lock_irqsave(&thi->t_lock, flags);
1645 switch (thi->t_state) {
1647 dev_info(DEV, "Starting %s thread (from %s [%d])\n",
1648 me, current->comm, current->pid);
1650 /* Get ref on module for thread - this is released when thread exits */
1651 if (!try_module_get(THIS_MODULE)) {
1652 dev_err(DEV, "Failed to get module reference in drbd_thread_start\n");
1653 spin_unlock_irqrestore(&thi->t_lock, flags);
1657 init_completion(&thi->stop);
1658 D_ASSERT(thi->task == NULL);
1659 thi->reset_cpu_mask = 1;
1660 thi->t_state = Running;
1661 spin_unlock_irqrestore(&thi->t_lock, flags);
1662 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
1664 nt = kthread_create(drbd_thread_setup, (void *) thi,
1665 "drbd%d_%s", mdev_to_minor(mdev), me);
1668 dev_err(DEV, "Couldn't start thread\n");
1670 module_put(THIS_MODULE);
1673 spin_lock_irqsave(&thi->t_lock, flags);
1675 thi->t_state = Running;
1676 spin_unlock_irqrestore(&thi->t_lock, flags);
1677 wake_up_process(nt);
1680 thi->t_state = Restarting;
1681 dev_info(DEV, "Restarting %s thread (from %s [%d])\n",
1682 me, current->comm, current->pid);
1687 spin_unlock_irqrestore(&thi->t_lock, flags);
1695 void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
1697 unsigned long flags;
1699 enum drbd_thread_state ns = restart ? Restarting : Exiting;
1701 /* may be called from state engine, holding the req lock irqsave */
1702 spin_lock_irqsave(&thi->t_lock, flags);
1704 if (thi->t_state == None) {
1705 spin_unlock_irqrestore(&thi->t_lock, flags);
1707 drbd_thread_start(thi);
1711 if (thi->t_state != ns) {
1712 if (thi->task == NULL) {
1713 spin_unlock_irqrestore(&thi->t_lock, flags);
1719 init_completion(&thi->stop);
1720 if (thi->task != current)
1721 force_sig(DRBD_SIGKILL, thi->task);
1725 spin_unlock_irqrestore(&thi->t_lock, flags);
1728 wait_for_completion(&thi->stop);
1733 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
1734 * @mdev: DRBD device.
1736 * Forces all threads of a device onto the same CPU. This is beneficial for
1737 * DRBD's performance. May be overwritten by user's configuration.
1739 void drbd_calc_cpu_mask(struct drbd_conf *mdev)
1743 /* user override. */
1744 if (cpumask_weight(mdev->cpu_mask))
1747 ord = mdev_to_minor(mdev) % cpumask_weight(cpu_online_mask);
1748 for_each_online_cpu(cpu) {
1750 cpumask_set_cpu(cpu, mdev->cpu_mask);
1754 /* should not be reached */
1755 cpumask_setall(mdev->cpu_mask);
1759 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
1760 * @mdev: DRBD device.
1762 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
1765 void drbd_thread_current_set_cpu(struct drbd_conf *mdev)
1767 struct task_struct *p = current;
1768 struct drbd_thread *thi =
1769 p == mdev->asender.task ? &mdev->asender :
1770 p == mdev->receiver.task ? &mdev->receiver :
1771 p == mdev->worker.task ? &mdev->worker :
1775 if (!thi->reset_cpu_mask)
1777 thi->reset_cpu_mask = 0;
1778 set_cpus_allowed_ptr(p, mdev->cpu_mask);
1782 /* the appropriate socket mutex must be held already */
1783 int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1784 enum drbd_packets cmd, struct p_header80 *h,
1785 size_t size, unsigned msg_flags)
1789 ERR_IF(!h) return false;
1790 ERR_IF(!size) return false;
1792 h->magic = BE_DRBD_MAGIC;
1793 h->command = cpu_to_be16(cmd);
1794 h->length = cpu_to_be16(size-sizeof(struct p_header80));
1796 sent = drbd_send(mdev, sock, h, size, msg_flags);
1798 ok = (sent == size);
1800 dev_err(DEV, "short sent %s size=%d sent=%d\n",
1801 cmdname(cmd), (int)size, sent);
1805 /* don't pass the socket. we may only look at it
1806 * when we hold the appropriate socket mutex.
1808 int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1809 enum drbd_packets cmd, struct p_header80 *h, size_t size)
1812 struct socket *sock;
1814 if (use_data_socket) {
1815 mutex_lock(&mdev->data.mutex);
1816 sock = mdev->data.socket;
1818 mutex_lock(&mdev->meta.mutex);
1819 sock = mdev->meta.socket;
1822 /* drbd_disconnect() could have called drbd_free_sock()
1823 * while we were waiting in down()... */
1824 if (likely(sock != NULL))
1825 ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0);
1827 if (use_data_socket)
1828 mutex_unlock(&mdev->data.mutex);
1830 mutex_unlock(&mdev->meta.mutex);
1834 int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
1837 struct p_header80 h;
1840 h.magic = BE_DRBD_MAGIC;
1841 h.command = cpu_to_be16(cmd);
1842 h.length = cpu_to_be16(size);
1844 if (!drbd_get_data_sock(mdev))
1848 drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0));
1850 drbd_send(mdev, mdev->data.socket, data, size, 0));
1852 drbd_put_data_sock(mdev);
1857 int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc)
1859 struct p_rs_param_95 *p;
1860 struct socket *sock;
1862 const int apv = mdev->agreed_pro_version;
1864 size = apv <= 87 ? sizeof(struct p_rs_param)
1865 : apv == 88 ? sizeof(struct p_rs_param)
1866 + strlen(mdev->sync_conf.verify_alg) + 1
1867 : apv <= 94 ? sizeof(struct p_rs_param_89)
1868 : /* apv >= 95 */ sizeof(struct p_rs_param_95);
1870 /* used from admin command context and receiver/worker context.
1871 * to avoid kmalloc, grab the socket right here,
1872 * then use the pre-allocated sbuf there */
1873 mutex_lock(&mdev->data.mutex);
1874 sock = mdev->data.socket;
1876 if (likely(sock != NULL)) {
1877 enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
1879 p = &mdev->data.sbuf.rs_param_95;
1881 /* initialize verify_alg and csums_alg */
1882 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
1884 p->rate = cpu_to_be32(sc->rate);
1885 p->c_plan_ahead = cpu_to_be32(sc->c_plan_ahead);
1886 p->c_delay_target = cpu_to_be32(sc->c_delay_target);
1887 p->c_fill_target = cpu_to_be32(sc->c_fill_target);
1888 p->c_max_rate = cpu_to_be32(sc->c_max_rate);
1891 strcpy(p->verify_alg, mdev->sync_conf.verify_alg);
1893 strcpy(p->csums_alg, mdev->sync_conf.csums_alg);
1895 rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
1897 rv = 0; /* not ok */
1899 mutex_unlock(&mdev->data.mutex);
1904 int drbd_send_protocol(struct drbd_conf *mdev)
1906 struct p_protocol *p;
1909 size = sizeof(struct p_protocol);
1911 if (mdev->agreed_pro_version >= 87)
1912 size += strlen(mdev->net_conf->integrity_alg) + 1;
1914 /* we must not recurse into our own queue,
1915 * as that is blocked during handshake */
1916 p = kmalloc(size, GFP_NOIO);
1920 p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol);
1921 p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p);
1922 p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p);
1923 p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p);
1924 p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries);
1927 if (mdev->net_conf->want_lose)
1929 if (mdev->net_conf->dry_run) {
1930 if (mdev->agreed_pro_version >= 92)
1933 dev_err(DEV, "--dry-run is not supported by peer");
1938 p->conn_flags = cpu_to_be32(cf);
1940 if (mdev->agreed_pro_version >= 87)
1941 strcpy(p->integrity_alg, mdev->net_conf->integrity_alg);
1943 rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL,
1944 (struct p_header80 *)p, size);
1949 int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
1954 if (!get_ldev_if_state(mdev, D_NEGOTIATING))
1957 for (i = UI_CURRENT; i < UI_SIZE; i++)
1958 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
1960 mdev->comm_bm_set = drbd_bm_total_weight(mdev);
1961 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
1962 uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
1963 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
1964 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
1965 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
1969 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS,
1970 (struct p_header80 *)&p, sizeof(p));
1973 int drbd_send_uuids(struct drbd_conf *mdev)
1975 return _drbd_send_uuids(mdev, 0);
1978 int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
1980 return _drbd_send_uuids(mdev, 8);
1984 int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val)
1988 p.uuid = cpu_to_be64(val);
1990 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID,
1991 (struct p_header80 *)&p, sizeof(p));
1994 int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags)
1997 sector_t d_size, u_size;
2001 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
2002 D_ASSERT(mdev->ldev->backing_bdev);
2003 d_size = drbd_get_max_capacity(mdev->ldev);
2004 u_size = mdev->ldev->dc.disk_size;
2005 q_order_type = drbd_queue_order_type(mdev);
2010 q_order_type = QUEUE_ORDERED_NONE;
2013 p.d_size = cpu_to_be64(d_size);
2014 p.u_size = cpu_to_be64(u_size);
2015 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
2016 p.max_bio_size = cpu_to_be32(queue_max_hw_sectors(mdev->rq_queue) << 9);
2017 p.queue_order_type = cpu_to_be16(q_order_type);
2018 p.dds_flags = cpu_to_be16(flags);
2020 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES,
2021 (struct p_header80 *)&p, sizeof(p));
2026 * drbd_send_state() - Sends the drbd state to the peer
2027 * @mdev: DRBD device.
2029 int drbd_send_state(struct drbd_conf *mdev)
2031 struct socket *sock;
2035 /* Grab state lock so we wont send state if we're in the middle
2036 * of a cluster wide state change on another thread */
2037 drbd_state_lock(mdev);
2039 mutex_lock(&mdev->data.mutex);
2041 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
2042 sock = mdev->data.socket;
2044 if (likely(sock != NULL)) {
2045 ok = _drbd_send_cmd(mdev, sock, P_STATE,
2046 (struct p_header80 *)&p, sizeof(p), 0);
2049 mutex_unlock(&mdev->data.mutex);
2051 drbd_state_unlock(mdev);
2055 int drbd_send_state_req(struct drbd_conf *mdev,
2056 union drbd_state mask, union drbd_state val)
2058 struct p_req_state p;
2060 p.mask = cpu_to_be32(mask.i);
2061 p.val = cpu_to_be32(val.i);
2063 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ,
2064 (struct p_header80 *)&p, sizeof(p));
2067 int drbd_send_sr_reply(struct drbd_conf *mdev, enum drbd_state_rv retcode)
2069 struct p_req_state_reply p;
2071 p.retcode = cpu_to_be32(retcode);
2073 return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY,
2074 (struct p_header80 *)&p, sizeof(p));
2077 int fill_bitmap_rle_bits(struct drbd_conf *mdev,
2078 struct p_compressed_bm *p,
2079 struct bm_xfer_ctx *c)
2081 struct bitstream bs;
2082 unsigned long plain_bits;
2089 /* may we use this feature? */
2090 if ((mdev->sync_conf.use_rle == 0) ||
2091 (mdev->agreed_pro_version < 90))
2094 if (c->bit_offset >= c->bm_bits)
2095 return 0; /* nothing to do. */
2097 /* use at most thus many bytes */
2098 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
2099 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
2100 /* plain bits covered in this code string */
2103 /* p->encoding & 0x80 stores whether the first run length is set.
2104 * bit offset is implicit.
2105 * start with toggle == 2 to be able to tell the first iteration */
2108 /* see how much plain bits we can stuff into one packet
2109 * using RLE and VLI. */
2111 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
2112 : _drbd_bm_find_next(mdev, c->bit_offset);
2115 rl = tmp - c->bit_offset;
2117 if (toggle == 2) { /* first iteration */
2119 /* the first checked bit was set,
2120 * store start value, */
2121 DCBP_set_start(p, 1);
2122 /* but skip encoding of zero run length */
2126 DCBP_set_start(p, 0);
2129 /* paranoia: catch zero runlength.
2130 * can only happen if bitmap is modified while we scan it. */
2132 dev_err(DEV, "unexpected zero runlength while encoding bitmap "
2133 "t:%u bo:%lu\n", toggle, c->bit_offset);
2137 bits = vli_encode_bits(&bs, rl);
2138 if (bits == -ENOBUFS) /* buffer full */
2141 dev_err(DEV, "error while encoding bitmap: %d\n", bits);
2147 c->bit_offset = tmp;
2148 } while (c->bit_offset < c->bm_bits);
2150 len = bs.cur.b - p->code + !!bs.cur.bit;
2152 if (plain_bits < (len << 3)) {
2153 /* incompressible with this method.
2154 * we need to rewind both word and bit position. */
2155 c->bit_offset -= plain_bits;
2156 bm_xfer_ctx_bit_to_word_offset(c);
2157 c->bit_offset = c->word_offset * BITS_PER_LONG;
2161 /* RLE + VLI was able to compress it just fine.
2162 * update c->word_offset. */
2163 bm_xfer_ctx_bit_to_word_offset(c);
2165 /* store pad_bits */
2166 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
2172 * send_bitmap_rle_or_plain
2174 * Return 0 when done, 1 when another iteration is needed, and a negative error
2175 * code upon failure.
2178 send_bitmap_rle_or_plain(struct drbd_conf *mdev,
2179 struct p_header80 *h, struct bm_xfer_ctx *c)
2181 struct p_compressed_bm *p = (void*)h;
2182 unsigned long num_words;
2186 len = fill_bitmap_rle_bits(mdev, p, c);
2192 DCBP_set_code(p, RLE_VLI_Bits);
2193 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h,
2194 sizeof(*p) + len, 0);
2197 c->bytes[0] += sizeof(*p) + len;
2199 if (c->bit_offset >= c->bm_bits)
2202 /* was not compressible.
2203 * send a buffer full of plain text bits instead. */
2204 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
2205 len = num_words * sizeof(long);
2207 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
2208 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP,
2209 h, sizeof(struct p_header80) + len, 0);
2210 c->word_offset += num_words;
2211 c->bit_offset = c->word_offset * BITS_PER_LONG;
2214 c->bytes[1] += sizeof(struct p_header80) + len;
2216 if (c->bit_offset > c->bm_bits)
2217 c->bit_offset = c->bm_bits;
2221 INFO_bm_xfer_stats(mdev, "send", c);
2229 /* See the comment at receive_bitmap() */
2230 int _drbd_send_bitmap(struct drbd_conf *mdev)
2232 struct bm_xfer_ctx c;
2233 struct p_header80 *p;
2236 ERR_IF(!mdev->bitmap) return false;
2238 /* maybe we should use some per thread scratch page,
2239 * and allocate that during initial device creation? */
2240 p = (struct p_header80 *) __get_free_page(GFP_NOIO);
2242 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
2246 if (get_ldev(mdev)) {
2247 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
2248 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
2249 drbd_bm_set_all(mdev);
2250 if (drbd_bm_write(mdev)) {
2251 /* write_bm did fail! Leave full sync flag set in Meta P_DATA
2252 * but otherwise process as per normal - need to tell other
2253 * side that a full resync is required! */
2254 dev_err(DEV, "Failed to write bitmap to disk!\n");
2256 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2263 c = (struct bm_xfer_ctx) {
2264 .bm_bits = drbd_bm_bits(mdev),
2265 .bm_words = drbd_bm_words(mdev),
2269 err = send_bitmap_rle_or_plain(mdev, p, &c);
2272 free_page((unsigned long) p);
2276 int drbd_send_bitmap(struct drbd_conf *mdev)
2280 if (!drbd_get_data_sock(mdev))
2282 err = !_drbd_send_bitmap(mdev);
2283 drbd_put_data_sock(mdev);
2287 int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
2290 struct p_barrier_ack p;
2292 p.barrier = barrier_nr;
2293 p.set_size = cpu_to_be32(set_size);
2295 if (mdev->state.conn < C_CONNECTED)
2297 ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK,
2298 (struct p_header80 *)&p, sizeof(p));
2303 * _drbd_send_ack() - Sends an ack packet
2304 * @mdev: DRBD device.
2305 * @cmd: Packet command code.
2306 * @sector: sector, needs to be in big endian byte order
2307 * @blksize: size in byte, needs to be in big endian byte order
2308 * @block_id: Id, big endian byte order
2310 static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
2316 struct p_block_ack p;
2319 p.block_id = block_id;
2320 p.blksize = blksize;
2321 p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq));
2323 if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED)
2325 ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd,
2326 (struct p_header80 *)&p, sizeof(p));
2330 /* dp->sector and dp->block_id already/still in network byte order,
2331 * data_size is payload size according to dp->head,
2332 * and may need to be corrected for digest size. */
2333 int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
2334 struct p_data *dp, int data_size)
2336 data_size -= (mdev->agreed_pro_version >= 87 && mdev->integrity_r_tfm) ?
2337 crypto_hash_digestsize(mdev->integrity_r_tfm) : 0;
2338 return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
2342 int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
2343 struct p_block_req *rp)
2345 return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
2349 * drbd_send_ack() - Sends an ack packet
2350 * @mdev: DRBD device.
2351 * @cmd: Packet command code.
2354 int drbd_send_ack(struct drbd_conf *mdev,
2355 enum drbd_packets cmd, struct drbd_epoch_entry *e)
2357 return _drbd_send_ack(mdev, cmd,
2358 cpu_to_be64(e->sector),
2359 cpu_to_be32(e->size),
2363 /* This function misuses the block_id field to signal if the blocks
2364 * are is sync or not. */
2365 int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
2366 sector_t sector, int blksize, u64 block_id)
2368 return _drbd_send_ack(mdev, cmd,
2369 cpu_to_be64(sector),
2370 cpu_to_be32(blksize),
2371 cpu_to_be64(block_id));
2374 int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
2375 sector_t sector, int size, u64 block_id)
2378 struct p_block_req p;
2380 p.sector = cpu_to_be64(sector);
2381 p.block_id = block_id;
2382 p.blksize = cpu_to_be32(size);
2384 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd,
2385 (struct p_header80 *)&p, sizeof(p));
2389 int drbd_send_drequest_csum(struct drbd_conf *mdev,
2390 sector_t sector, int size,
2391 void *digest, int digest_size,
2392 enum drbd_packets cmd)
2395 struct p_block_req p;
2397 p.sector = cpu_to_be64(sector);
2398 p.block_id = BE_DRBD_MAGIC + 0xbeef;
2399 p.blksize = cpu_to_be32(size);
2401 p.head.magic = BE_DRBD_MAGIC;
2402 p.head.command = cpu_to_be16(cmd);
2403 p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header80) + digest_size);
2405 mutex_lock(&mdev->data.mutex);
2407 ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0));
2408 ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0));
2410 mutex_unlock(&mdev->data.mutex);
2415 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
2418 struct p_block_req p;
2420 p.sector = cpu_to_be64(sector);
2421 p.block_id = BE_DRBD_MAGIC + 0xbabe;
2422 p.blksize = cpu_to_be32(size);
2424 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST,
2425 (struct p_header80 *)&p, sizeof(p));
2429 /* called on sndtimeo
2430 * returns false if we should retry,
2431 * true if we think connection is dead
2433 static int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock)
2436 /* long elapsed = (long)(jiffies - mdev->last_received); */
2438 drop_it = mdev->meta.socket == sock
2439 || !mdev->asender.task
2440 || get_t_state(&mdev->asender) != Running
2441 || mdev->state.conn < C_CONNECTED;
2446 drop_it = !--mdev->ko_count;
2448 dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
2449 current->comm, current->pid, mdev->ko_count);
2453 return drop_it; /* && (mdev->state == R_PRIMARY) */;
2456 /* The idea of sendpage seems to be to put some kind of reference
2457 * to the page into the skb, and to hand it over to the NIC. In
2458 * this process get_page() gets called.
2460 * As soon as the page was really sent over the network put_page()
2461 * gets called by some part of the network layer. [ NIC driver? ]
2463 * [ get_page() / put_page() increment/decrement the count. If count
2464 * reaches 0 the page will be freed. ]
2466 * This works nicely with pages from FSs.
2467 * But this means that in protocol A we might signal IO completion too early!
2469 * In order not to corrupt data during a resync we must make sure
2470 * that we do not reuse our own buffer pages (EEs) to early, therefore
2471 * we have the net_ee list.
2473 * XFS seems to have problems, still, it submits pages with page_count == 0!
2474 * As a workaround, we disable sendpage on pages
2475 * with page_count == 0 or PageSlab.
2477 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
2478 int offset, size_t size, unsigned msg_flags)
2480 int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, msg_flags);
2483 mdev->send_cnt += size>>9;
2484 return sent == size;
2487 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
2488 int offset, size_t size, unsigned msg_flags)
2490 mm_segment_t oldfs = get_fs();
2494 /* e.g. XFS meta- & log-data is in slab pages, which have a
2495 * page_count of 0 and/or have PageSlab() set.
2496 * we cannot use send_page for those, as that does get_page();
2497 * put_page(); and would cause either a VM_BUG directly, or
2498 * __page_cache_release a page that would actually still be referenced
2499 * by someone, leading to some obscure delayed Oops somewhere else. */
2500 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
2501 return _drbd_no_send_page(mdev, page, offset, size, msg_flags);
2503 msg_flags |= MSG_NOSIGNAL;
2504 drbd_update_congested(mdev);
2507 sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page,
2510 if (sent == -EAGAIN) {
2511 if (we_should_drop_the_connection(mdev,
2518 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
2519 __func__, (int)size, len, sent);
2524 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
2526 clear_bit(NET_CONGESTED, &mdev->flags);
2530 mdev->send_cnt += size>>9;
2534 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
2536 struct bio_vec *bvec;
2538 /* hint all but last page with MSG_MORE */
2539 __bio_for_each_segment(bvec, bio, i, 0) {
2540 if (!_drbd_no_send_page(mdev, bvec->bv_page,
2541 bvec->bv_offset, bvec->bv_len,
2542 i == bio->bi_vcnt -1 ? 0 : MSG_MORE))
2548 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
2550 struct bio_vec *bvec;
2552 /* hint all but last page with MSG_MORE */
2553 __bio_for_each_segment(bvec, bio, i, 0) {
2554 if (!_drbd_send_page(mdev, bvec->bv_page,
2555 bvec->bv_offset, bvec->bv_len,
2556 i == bio->bi_vcnt -1 ? 0 : MSG_MORE))
2562 static int _drbd_send_zc_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e)
2564 struct page *page = e->pages;
2565 unsigned len = e->size;
2566 /* hint all but last page with MSG_MORE */
2567 page_chain_for_each(page) {
2568 unsigned l = min_t(unsigned, len, PAGE_SIZE);
2569 if (!_drbd_send_page(mdev, page, 0, l,
2570 page_chain_next(page) ? MSG_MORE : 0))
2577 static u32 bio_flags_to_wire(struct drbd_conf *mdev, unsigned long bi_rw)
2579 if (mdev->agreed_pro_version >= 95)
2580 return (bi_rw & REQ_SYNC ? DP_RW_SYNC : 0) |
2581 (bi_rw & REQ_FUA ? DP_FUA : 0) |
2582 (bi_rw & REQ_FLUSH ? DP_FLUSH : 0) |
2583 (bi_rw & REQ_DISCARD ? DP_DISCARD : 0);
2585 return bi_rw & REQ_SYNC ? DP_RW_SYNC : 0;
2588 /* Used to send write requests
2589 * R_PRIMARY -> Peer (P_DATA)
2591 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
2595 unsigned int dp_flags = 0;
2599 if (!drbd_get_data_sock(mdev))
2602 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2603 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2605 if (req->size <= DRBD_MAX_SIZE_H80_PACKET) {
2606 p.head.h80.magic = BE_DRBD_MAGIC;
2607 p.head.h80.command = cpu_to_be16(P_DATA);
2609 cpu_to_be16(sizeof(p) - sizeof(union p_header) + dgs + req->size);
2611 p.head.h95.magic = BE_DRBD_MAGIC_BIG;
2612 p.head.h95.command = cpu_to_be16(P_DATA);
2614 cpu_to_be32(sizeof(p) - sizeof(union p_header) + dgs + req->size);
2617 p.sector = cpu_to_be64(req->sector);
2618 p.block_id = (unsigned long)req;
2619 p.seq_num = cpu_to_be32(req->seq_num =
2620 atomic_add_return(1, &mdev->packet_seq));
2622 dp_flags = bio_flags_to_wire(mdev, req->master_bio->bi_rw);
2624 if (mdev->state.conn >= C_SYNC_SOURCE &&
2625 mdev->state.conn <= C_PAUSED_SYNC_T)
2626 dp_flags |= DP_MAY_SET_IN_SYNC;
2628 p.dp_flags = cpu_to_be32(dp_flags);
2629 set_bit(UNPLUG_REMOTE, &mdev->flags);
2631 drbd_send(mdev, mdev->data.socket, &p, sizeof(p), dgs ? MSG_MORE : 0));
2633 dgb = mdev->int_dig_out;
2634 drbd_csum_bio(mdev, mdev->integrity_w_tfm, req->master_bio, dgb);
2635 ok = dgs == drbd_send(mdev, mdev->data.socket, dgb, dgs, 0);
2638 /* For protocol A, we have to memcpy the payload into
2639 * socket buffers, as we may complete right away
2640 * as soon as we handed it over to tcp, at which point the data
2641 * pages may become invalid.
2643 * For data-integrity enabled, we copy it as well, so we can be
2644 * sure that even if the bio pages may still be modified, it
2645 * won't change the data on the wire, thus if the digest checks
2646 * out ok after sending on this side, but does not fit on the
2647 * receiving side, we sure have detected corruption elsewhere.
2649 if (mdev->net_conf->wire_protocol == DRBD_PROT_A || dgs)
2650 ok = _drbd_send_bio(mdev, req->master_bio);
2652 ok = _drbd_send_zc_bio(mdev, req->master_bio);
2654 /* double check digest, sometimes buffers have been modified in flight. */
2655 if (dgs > 0 && dgs <= 64) {
2656 /* 64 byte, 512 bit, is the larges digest size
2657 * currently supported in kernel crypto. */
2658 unsigned char digest[64];
2659 drbd_csum_bio(mdev, mdev->integrity_w_tfm, req->master_bio, digest);
2660 if (memcmp(mdev->int_dig_out, digest, dgs)) {
2662 "Digest mismatch, buffer modified by upper layers during write: %llus +%u\n",
2663 (unsigned long long)req->sector, req->size);
2665 } /* else if (dgs > 64) {
2666 ... Be noisy about digest too large ...
2670 drbd_put_data_sock(mdev);
2675 /* answer packet, used to send data back for read requests:
2676 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
2677 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
2679 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
2680 struct drbd_epoch_entry *e)
2687 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2688 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2690 if (e->size <= DRBD_MAX_SIZE_H80_PACKET) {
2691 p.head.h80.magic = BE_DRBD_MAGIC;
2692 p.head.h80.command = cpu_to_be16(cmd);
2694 cpu_to_be16(sizeof(p) - sizeof(struct p_header80) + dgs + e->size);
2696 p.head.h95.magic = BE_DRBD_MAGIC_BIG;
2697 p.head.h95.command = cpu_to_be16(cmd);
2699 cpu_to_be32(sizeof(p) - sizeof(struct p_header80) + dgs + e->size);
2702 p.sector = cpu_to_be64(e->sector);
2703 p.block_id = e->block_id;
2704 /* p.seq_num = 0; No sequence numbers here.. */
2706 /* Only called by our kernel thread.
2707 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
2708 * in response to admin command or module unload.
2710 if (!drbd_get_data_sock(mdev))
2713 ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), dgs ? MSG_MORE : 0);
2715 dgb = mdev->int_dig_out;
2716 drbd_csum_ee(mdev, mdev->integrity_w_tfm, e, dgb);
2717 ok = dgs == drbd_send(mdev, mdev->data.socket, dgb, dgs, 0);
2720 ok = _drbd_send_zc_ee(mdev, e);
2722 drbd_put_data_sock(mdev);
2727 int drbd_send_oos(struct drbd_conf *mdev, struct drbd_request *req)
2729 struct p_block_desc p;
2731 p.sector = cpu_to_be64(req->sector);
2732 p.blksize = cpu_to_be32(req->size);
2734 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OUT_OF_SYNC, &p.head, sizeof(p));
2738 drbd_send distinguishes two cases:
2740 Packets sent via the data socket "sock"
2741 and packets sent via the meta data socket "msock"
2744 -----------------+-------------------------+------------------------------
2745 timeout conf.timeout / 2 conf.timeout / 2
2746 timeout action send a ping via msock Abort communication
2747 and close all sockets
2751 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
2753 int drbd_send(struct drbd_conf *mdev, struct socket *sock,
2754 void *buf, size_t size, unsigned msg_flags)
2763 /* THINK if (signal_pending) return ... ? */
2768 msg.msg_name = NULL;
2769 msg.msg_namelen = 0;
2770 msg.msg_control = NULL;
2771 msg.msg_controllen = 0;
2772 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
2774 if (sock == mdev->data.socket) {
2775 mdev->ko_count = mdev->net_conf->ko_count;
2776 drbd_update_congested(mdev);
2780 * tcp_sendmsg does _not_ use its size parameter at all ?
2782 * -EAGAIN on timeout, -EINTR on signal.
2785 * do we need to block DRBD_SIG if sock == &meta.socket ??
2786 * otherwise wake_asender() might interrupt some send_*Ack !
2788 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
2789 if (rv == -EAGAIN) {
2790 if (we_should_drop_the_connection(mdev, sock))
2797 flush_signals(current);
2805 } while (sent < size);
2807 if (sock == mdev->data.socket)
2808 clear_bit(NET_CONGESTED, &mdev->flags);
2811 if (rv != -EAGAIN) {
2812 dev_err(DEV, "%s_sendmsg returned %d\n",
2813 sock == mdev->meta.socket ? "msock" : "sock",
2815 drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE));
2817 drbd_force_state(mdev, NS(conn, C_TIMEOUT));
2823 static int drbd_open(struct block_device *bdev, fmode_t mode)
2825 struct drbd_conf *mdev = bdev->bd_disk->private_data;
2826 unsigned long flags;
2829 mutex_lock(&drbd_main_mutex);
2830 spin_lock_irqsave(&mdev->req_lock, flags);
2831 /* to have a stable mdev->state.role
2832 * and no race with updating open_cnt */
2834 if (mdev->state.role != R_PRIMARY) {
2835 if (mode & FMODE_WRITE)
2837 else if (!allow_oos)
2843 spin_unlock_irqrestore(&mdev->req_lock, flags);
2844 mutex_unlock(&drbd_main_mutex);
2849 static int drbd_release(struct gendisk *gd, fmode_t mode)
2851 struct drbd_conf *mdev = gd->private_data;
2852 mutex_lock(&drbd_main_mutex);
2854 mutex_unlock(&drbd_main_mutex);
2858 static void drbd_set_defaults(struct drbd_conf *mdev)
2860 /* This way we get a compile error when sync_conf grows,
2861 and we forgot to initialize it here */
2862 mdev->sync_conf = (struct syncer_conf) {
2863 /* .rate = */ DRBD_RATE_DEF,
2864 /* .after = */ DRBD_AFTER_DEF,
2865 /* .al_extents = */ DRBD_AL_EXTENTS_DEF,
2866 /* .verify_alg = */ {}, 0,
2867 /* .cpu_mask = */ {}, 0,
2868 /* .csums_alg = */ {}, 0,
2870 /* .on_no_data = */ DRBD_ON_NO_DATA_DEF,
2871 /* .c_plan_ahead = */ DRBD_C_PLAN_AHEAD_DEF,
2872 /* .c_delay_target = */ DRBD_C_DELAY_TARGET_DEF,
2873 /* .c_fill_target = */ DRBD_C_FILL_TARGET_DEF,
2874 /* .c_max_rate = */ DRBD_C_MAX_RATE_DEF,
2875 /* .c_min_rate = */ DRBD_C_MIN_RATE_DEF
2878 /* Have to use that way, because the layout differs between
2879 big endian and little endian */
2880 mdev->state = (union drbd_state) {
2881 { .role = R_SECONDARY,
2883 .conn = C_STANDALONE,
2892 void drbd_init_set_defaults(struct drbd_conf *mdev)
2894 /* the memset(,0,) did most of this.
2895 * note: only assignments, no allocation in here */
2897 drbd_set_defaults(mdev);
2899 atomic_set(&mdev->ap_bio_cnt, 0);
2900 atomic_set(&mdev->ap_pending_cnt, 0);
2901 atomic_set(&mdev->rs_pending_cnt, 0);
2902 atomic_set(&mdev->unacked_cnt, 0);
2903 atomic_set(&mdev->local_cnt, 0);
2904 atomic_set(&mdev->net_cnt, 0);
2905 atomic_set(&mdev->packet_seq, 0);
2906 atomic_set(&mdev->pp_in_use, 0);
2907 atomic_set(&mdev->pp_in_use_by_net, 0);
2908 atomic_set(&mdev->rs_sect_in, 0);
2909 atomic_set(&mdev->rs_sect_ev, 0);
2910 atomic_set(&mdev->ap_in_flight, 0);
2912 mutex_init(&mdev->md_io_mutex);
2913 mutex_init(&mdev->data.mutex);
2914 mutex_init(&mdev->meta.mutex);
2915 sema_init(&mdev->data.work.s, 0);
2916 sema_init(&mdev->meta.work.s, 0);
2917 mutex_init(&mdev->state_mutex);
2919 spin_lock_init(&mdev->data.work.q_lock);
2920 spin_lock_init(&mdev->meta.work.q_lock);
2922 spin_lock_init(&mdev->al_lock);
2923 spin_lock_init(&mdev->req_lock);
2924 spin_lock_init(&mdev->peer_seq_lock);
2925 spin_lock_init(&mdev->epoch_lock);
2927 INIT_LIST_HEAD(&mdev->active_ee);
2928 INIT_LIST_HEAD(&mdev->sync_ee);
2929 INIT_LIST_HEAD(&mdev->done_ee);
2930 INIT_LIST_HEAD(&mdev->read_ee);
2931 INIT_LIST_HEAD(&mdev->net_ee);
2932 INIT_LIST_HEAD(&mdev->resync_reads);
2933 INIT_LIST_HEAD(&mdev->data.work.q);
2934 INIT_LIST_HEAD(&mdev->meta.work.q);
2935 INIT_LIST_HEAD(&mdev->resync_work.list);
2936 INIT_LIST_HEAD(&mdev->unplug_work.list);
2937 INIT_LIST_HEAD(&mdev->go_diskless.list);
2938 INIT_LIST_HEAD(&mdev->md_sync_work.list);
2939 INIT_LIST_HEAD(&mdev->start_resync_work.list);
2940 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
2942 mdev->resync_work.cb = w_resync_inactive;
2943 mdev->unplug_work.cb = w_send_write_hint;
2944 mdev->go_diskless.cb = w_go_diskless;
2945 mdev->md_sync_work.cb = w_md_sync;
2946 mdev->bm_io_work.w.cb = w_bitmap_io;
2947 init_timer(&mdev->resync_timer);
2948 init_timer(&mdev->md_sync_timer);
2949 mdev->resync_timer.function = resync_timer_fn;
2950 mdev->resync_timer.data = (unsigned long) mdev;
2951 mdev->md_sync_timer.function = md_sync_timer_fn;
2952 mdev->md_sync_timer.data = (unsigned long) mdev;
2954 init_waitqueue_head(&mdev->misc_wait);
2955 init_waitqueue_head(&mdev->state_wait);
2956 init_waitqueue_head(&mdev->net_cnt_wait);
2957 init_waitqueue_head(&mdev->ee_wait);
2958 init_waitqueue_head(&mdev->al_wait);
2959 init_waitqueue_head(&mdev->seq_wait);
2961 drbd_thread_init(mdev, &mdev->receiver, drbdd_init);
2962 drbd_thread_init(mdev, &mdev->worker, drbd_worker);
2963 drbd_thread_init(mdev, &mdev->asender, drbd_asender);
2965 mdev->agreed_pro_version = PRO_VERSION_MAX;
2966 mdev->write_ordering = WO_bdev_flush;
2967 mdev->resync_wenr = LC_FREE;
2970 void drbd_mdev_cleanup(struct drbd_conf *mdev)
2973 if (mdev->receiver.t_state != None)
2974 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
2975 mdev->receiver.t_state);
2977 /* no need to lock it, I'm the only thread alive */
2978 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
2979 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
2989 mdev->rs_failed = 0;
2990 mdev->rs_last_events = 0;
2991 mdev->rs_last_sect_ev = 0;
2992 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
2993 mdev->rs_mark_left[i] = 0;
2994 mdev->rs_mark_time[i] = 0;
2996 D_ASSERT(mdev->net_conf == NULL);
2998 drbd_set_my_capacity(mdev, 0);
3000 /* maybe never allocated. */
3001 drbd_bm_resize(mdev, 0, 1);
3002 drbd_bm_cleanup(mdev);
3005 drbd_free_resources(mdev);
3006 clear_bit(AL_SUSPENDED, &mdev->flags);
3009 * currently we drbd_init_ee only on module load, so
3010 * we may do drbd_release_ee only on module unload!
3012 D_ASSERT(list_empty(&mdev->active_ee));
3013 D_ASSERT(list_empty(&mdev->sync_ee));
3014 D_ASSERT(list_empty(&mdev->done_ee));
3015 D_ASSERT(list_empty(&mdev->read_ee));
3016 D_ASSERT(list_empty(&mdev->net_ee));
3017 D_ASSERT(list_empty(&mdev->resync_reads));
3018 D_ASSERT(list_empty(&mdev->data.work.q));
3019 D_ASSERT(list_empty(&mdev->meta.work.q));
3020 D_ASSERT(list_empty(&mdev->resync_work.list));
3021 D_ASSERT(list_empty(&mdev->unplug_work.list));
3022 D_ASSERT(list_empty(&mdev->go_diskless.list));
3026 static void drbd_destroy_mempools(void)
3030 while (drbd_pp_pool) {
3031 page = drbd_pp_pool;
3032 drbd_pp_pool = (struct page *)page_private(page);
3037 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
3039 if (drbd_ee_mempool)
3040 mempool_destroy(drbd_ee_mempool);
3041 if (drbd_request_mempool)
3042 mempool_destroy(drbd_request_mempool);
3044 kmem_cache_destroy(drbd_ee_cache);
3045 if (drbd_request_cache)
3046 kmem_cache_destroy(drbd_request_cache);
3047 if (drbd_bm_ext_cache)
3048 kmem_cache_destroy(drbd_bm_ext_cache);
3049 if (drbd_al_ext_cache)
3050 kmem_cache_destroy(drbd_al_ext_cache);
3052 drbd_ee_mempool = NULL;
3053 drbd_request_mempool = NULL;
3054 drbd_ee_cache = NULL;
3055 drbd_request_cache = NULL;
3056 drbd_bm_ext_cache = NULL;
3057 drbd_al_ext_cache = NULL;
3062 static int drbd_create_mempools(void)
3065 const int number = (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count;
3068 /* prepare our caches and mempools */
3069 drbd_request_mempool = NULL;
3070 drbd_ee_cache = NULL;
3071 drbd_request_cache = NULL;
3072 drbd_bm_ext_cache = NULL;
3073 drbd_al_ext_cache = NULL;
3074 drbd_pp_pool = NULL;
3077 drbd_request_cache = kmem_cache_create(
3078 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
3079 if (drbd_request_cache == NULL)
3082 drbd_ee_cache = kmem_cache_create(
3083 "drbd_ee", sizeof(struct drbd_epoch_entry), 0, 0, NULL);
3084 if (drbd_ee_cache == NULL)
3087 drbd_bm_ext_cache = kmem_cache_create(
3088 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
3089 if (drbd_bm_ext_cache == NULL)
3092 drbd_al_ext_cache = kmem_cache_create(
3093 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
3094 if (drbd_al_ext_cache == NULL)
3098 drbd_request_mempool = mempool_create(number,
3099 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
3100 if (drbd_request_mempool == NULL)
3103 drbd_ee_mempool = mempool_create(number,
3104 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
3105 if (drbd_ee_mempool == NULL)
3108 /* drbd's page pool */
3109 spin_lock_init(&drbd_pp_lock);
3111 for (i = 0; i < number; i++) {
3112 page = alloc_page(GFP_HIGHUSER);
3115 set_page_private(page, (unsigned long)drbd_pp_pool);
3116 drbd_pp_pool = page;
3118 drbd_pp_vacant = number;
3123 drbd_destroy_mempools(); /* in case we allocated some */
3127 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
3130 /* just so we have it. you never know what interesting things we
3131 * might want to do here some day...
3137 static struct notifier_block drbd_notifier = {
3138 .notifier_call = drbd_notify_sys,
3141 static void drbd_release_ee_lists(struct drbd_conf *mdev)
3145 rr = drbd_release_ee(mdev, &mdev->active_ee);
3147 dev_err(DEV, "%d EEs in active list found!\n", rr);
3149 rr = drbd_release_ee(mdev, &mdev->sync_ee);
3151 dev_err(DEV, "%d EEs in sync list found!\n", rr);
3153 rr = drbd_release_ee(mdev, &mdev->read_ee);
3155 dev_err(DEV, "%d EEs in read list found!\n", rr);
3157 rr = drbd_release_ee(mdev, &mdev->done_ee);
3159 dev_err(DEV, "%d EEs in done list found!\n", rr);
3161 rr = drbd_release_ee(mdev, &mdev->net_ee);
3163 dev_err(DEV, "%d EEs in net list found!\n", rr);
3166 /* caution. no locking.
3167 * currently only used from module cleanup code. */
3168 static void drbd_delete_device(unsigned int minor)
3170 struct drbd_conf *mdev = minor_to_mdev(minor);
3175 /* paranoia asserts */
3176 if (mdev->open_cnt != 0)
3177 dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,
3178 __FILE__ , __LINE__);
3180 ERR_IF (!list_empty(&mdev->data.work.q)) {
3181 struct list_head *lp;
3182 list_for_each(lp, &mdev->data.work.q) {
3183 dev_err(DEV, "lp = %p\n", lp);
3186 /* end paranoia asserts */
3188 del_gendisk(mdev->vdisk);
3190 /* cleanup stuff that may have been allocated during
3191 * device (re-)configuration or state changes */
3193 if (mdev->this_bdev)
3194 bdput(mdev->this_bdev);
3196 drbd_free_resources(mdev);
3198 drbd_release_ee_lists(mdev);
3200 /* should be free'd on disconnect? */
3201 kfree(mdev->ee_hash);
3203 mdev->ee_hash_s = 0;
3204 mdev->ee_hash = NULL;
3207 lc_destroy(mdev->act_log);
3208 lc_destroy(mdev->resync);
3210 kfree(mdev->p_uuid);
3211 /* mdev->p_uuid = NULL; */
3213 kfree(mdev->int_dig_out);
3214 kfree(mdev->int_dig_in);
3215 kfree(mdev->int_dig_vv);
3217 /* cleanup the rest that has been
3218 * allocated from drbd_new_device
3219 * and actually free the mdev itself */
3220 drbd_free_mdev(mdev);
3223 static void drbd_cleanup(void)
3227 unregister_reboot_notifier(&drbd_notifier);
3229 /* first remove proc,
3230 * drbdsetup uses it's presence to detect
3231 * whether DRBD is loaded.
3232 * If we would get stuck in proc removal,
3233 * but have netlink already deregistered,
3234 * some drbdsetup commands may wait forever
3238 remove_proc_entry("drbd", NULL);
3245 drbd_delete_device(i);
3246 drbd_destroy_mempools();
3251 unregister_blkdev(DRBD_MAJOR, "drbd");
3253 printk(KERN_INFO "drbd: module cleanup done.\n");
3257 * drbd_congested() - Callback for pdflush
3258 * @congested_data: User data
3259 * @bdi_bits: Bits pdflush is currently interested in
3261 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
3263 static int drbd_congested(void *congested_data, int bdi_bits)
3265 struct drbd_conf *mdev = congested_data;
3266 struct request_queue *q;
3270 if (!may_inc_ap_bio(mdev)) {
3271 /* DRBD has frozen IO */
3277 if (get_ldev(mdev)) {
3278 q = bdev_get_queue(mdev->ldev->backing_bdev);
3279 r = bdi_congested(&q->backing_dev_info, bdi_bits);
3285 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) {
3286 r |= (1 << BDI_async_congested);
3287 reason = reason == 'b' ? 'a' : 'n';
3291 mdev->congestion_reason = reason;
3295 struct drbd_conf *drbd_new_device(unsigned int minor)
3297 struct drbd_conf *mdev;
3298 struct gendisk *disk;
3299 struct request_queue *q;
3301 /* GFP_KERNEL, we are outside of all write-out paths */
3302 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
3305 if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL))
3306 goto out_no_cpumask;
3308 mdev->minor = minor;
3310 drbd_init_set_defaults(mdev);
3312 q = blk_alloc_queue(GFP_KERNEL);
3316 q->queuedata = mdev;
3318 disk = alloc_disk(1);
3323 set_disk_ro(disk, true);
3326 disk->major = DRBD_MAJOR;
3327 disk->first_minor = minor;
3328 disk->fops = &drbd_ops;
3329 sprintf(disk->disk_name, "drbd%d", minor);
3330 disk->private_data = mdev;
3332 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
3333 /* we have no partitions. we contain only ourselves. */
3334 mdev->this_bdev->bd_contains = mdev->this_bdev;
3336 q->backing_dev_info.congested_fn = drbd_congested;
3337 q->backing_dev_info.congested_data = mdev;
3339 blk_queue_make_request(q, drbd_make_request);
3340 blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE >> 9);
3341 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
3342 blk_queue_merge_bvec(q, drbd_merge_bvec);
3343 q->queue_lock = &mdev->req_lock;
3345 mdev->md_io_page = alloc_page(GFP_KERNEL);
3346 if (!mdev->md_io_page)
3347 goto out_no_io_page;
3349 if (drbd_bm_init(mdev))
3351 /* no need to lock access, we are still initializing this minor device. */
3355 mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL);
3356 if (!mdev->app_reads_hash)
3357 goto out_no_app_reads;
3359 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
3360 if (!mdev->current_epoch)
3363 INIT_LIST_HEAD(&mdev->current_epoch->list);
3368 /* out_whatever_else:
3369 kfree(mdev->current_epoch); */
3371 kfree(mdev->app_reads_hash);
3375 drbd_bm_cleanup(mdev);
3377 __free_page(mdev->md_io_page);
3381 blk_cleanup_queue(q);
3383 free_cpumask_var(mdev->cpu_mask);
3389 /* counterpart of drbd_new_device.
3390 * last part of drbd_delete_device. */
3391 void drbd_free_mdev(struct drbd_conf *mdev)
3393 kfree(mdev->current_epoch);
3394 kfree(mdev->app_reads_hash);
3396 if (mdev->bitmap) /* should no longer be there. */
3397 drbd_bm_cleanup(mdev);
3398 __free_page(mdev->md_io_page);
3399 put_disk(mdev->vdisk);
3400 blk_cleanup_queue(mdev->rq_queue);
3401 free_cpumask_var(mdev->cpu_mask);
3402 drbd_free_tl_hash(mdev);
3407 int __init drbd_init(void)
3411 if (sizeof(struct p_handshake) != 80) {
3413 "drbd: never change the size or layout "
3414 "of the HandShake packet.\n");
3418 if (1 > minor_count || minor_count > 255) {
3420 "drbd: invalid minor_count (%d)\n", minor_count);
3428 err = drbd_nl_init();
3432 err = register_blkdev(DRBD_MAJOR, "drbd");
3435 "drbd: unable to register block device major %d\n",
3440 register_reboot_notifier(&drbd_notifier);
3443 * allocate all necessary structs
3447 init_waitqueue_head(&drbd_pp_wait);
3449 drbd_proc = NULL; /* play safe for drbd_cleanup */
3450 minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
3455 err = drbd_create_mempools();
3459 drbd_proc = proc_create_data("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops, NULL);
3461 printk(KERN_ERR "drbd: unable to register proc file\n");
3465 rwlock_init(&global_state_lock);
3467 printk(KERN_INFO "drbd: initialized. "
3468 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
3469 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
3470 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
3471 printk(KERN_INFO "drbd: registered as block device major %d\n",
3473 printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
3475 return 0; /* Success! */
3480 /* currently always the case */
3481 printk(KERN_ERR "drbd: ran out of memory\n");
3483 printk(KERN_ERR "drbd: initialization failure\n");
3487 void drbd_free_bc(struct drbd_backing_dev *ldev)
3492 blkdev_put(ldev->backing_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
3493 blkdev_put(ldev->md_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
3498 void drbd_free_sock(struct drbd_conf *mdev)
3500 if (mdev->data.socket) {
3501 mutex_lock(&mdev->data.mutex);
3502 kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR);
3503 sock_release(mdev->data.socket);
3504 mdev->data.socket = NULL;
3505 mutex_unlock(&mdev->data.mutex);
3507 if (mdev->meta.socket) {
3508 mutex_lock(&mdev->meta.mutex);
3509 kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR);
3510 sock_release(mdev->meta.socket);
3511 mdev->meta.socket = NULL;
3512 mutex_unlock(&mdev->meta.mutex);
3517 void drbd_free_resources(struct drbd_conf *mdev)
3519 crypto_free_hash(mdev->csums_tfm);
3520 mdev->csums_tfm = NULL;
3521 crypto_free_hash(mdev->verify_tfm);
3522 mdev->verify_tfm = NULL;
3523 crypto_free_hash(mdev->cram_hmac_tfm);
3524 mdev->cram_hmac_tfm = NULL;
3525 crypto_free_hash(mdev->integrity_w_tfm);
3526 mdev->integrity_w_tfm = NULL;
3527 crypto_free_hash(mdev->integrity_r_tfm);
3528 mdev->integrity_r_tfm = NULL;
3530 drbd_free_sock(mdev);
3533 drbd_free_bc(mdev->ldev);
3534 mdev->ldev = NULL;);
3537 /* meta data management */
3539 struct meta_data_on_disk {
3540 u64 la_size; /* last agreed size. */
3541 u64 uuid[UI_SIZE]; /* UUIDs. */
3544 u32 flags; /* MDF */
3547 u32 al_offset; /* offset to this block */
3548 u32 al_nr_extents; /* important for restoring the AL */
3549 /* `-- act_log->nr_elements <-- sync_conf.al_extents */
3550 u32 bm_offset; /* offset to the bitmap, from here */
3551 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
3552 u32 reserved_u32[4];
3557 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
3558 * @mdev: DRBD device.
3560 void drbd_md_sync(struct drbd_conf *mdev)
3562 struct meta_data_on_disk *buffer;
3566 del_timer(&mdev->md_sync_timer);
3567 /* timer may be rearmed by drbd_md_mark_dirty() now. */
3568 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
3571 /* We use here D_FAILED and not D_ATTACHING because we try to write
3572 * metadata even if we detach due to a disk failure! */
3573 if (!get_ldev_if_state(mdev, D_FAILED))
3576 mutex_lock(&mdev->md_io_mutex);
3577 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3578 memset(buffer, 0, 512);
3580 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
3581 for (i = UI_CURRENT; i < UI_SIZE; i++)
3582 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
3583 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
3584 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
3586 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
3587 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
3588 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
3589 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
3590 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
3592 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
3594 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
3595 sector = mdev->ldev->md.md_offset;
3597 if (!drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
3598 /* this was a try anyways ... */
3599 dev_err(DEV, "meta data update failed!\n");
3600 drbd_chk_io_error(mdev, 1, true);
3603 /* Update mdev->ldev->md.la_size_sect,
3604 * since we updated it on metadata. */
3605 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
3607 mutex_unlock(&mdev->md_io_mutex);
3612 * drbd_md_read() - Reads in the meta data super block
3613 * @mdev: DRBD device.
3614 * @bdev: Device from which the meta data should be read in.
3616 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_code in case
3617 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
3619 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
3621 struct meta_data_on_disk *buffer;
3622 int i, rv = NO_ERROR;
3624 if (!get_ldev_if_state(mdev, D_ATTACHING))
3625 return ERR_IO_MD_DISK;
3627 mutex_lock(&mdev->md_io_mutex);
3628 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3630 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
3631 /* NOTE: cant do normal error processing here as this is
3632 called BEFORE disk is attached */
3633 dev_err(DEV, "Error while reading metadata.\n");
3634 rv = ERR_IO_MD_DISK;
3638 if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) {
3639 dev_err(DEV, "Error while reading metadata, magic not found.\n");
3640 rv = ERR_MD_INVALID;
3643 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
3644 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
3645 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
3646 rv = ERR_MD_INVALID;
3649 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
3650 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
3651 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
3652 rv = ERR_MD_INVALID;
3655 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
3656 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
3657 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
3658 rv = ERR_MD_INVALID;
3662 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
3663 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
3664 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
3665 rv = ERR_MD_INVALID;
3669 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
3670 for (i = UI_CURRENT; i < UI_SIZE; i++)
3671 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
3672 bdev->md.flags = be32_to_cpu(buffer->flags);
3673 mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents);
3674 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
3676 if (mdev->sync_conf.al_extents < 7)
3677 mdev->sync_conf.al_extents = 127;
3680 mutex_unlock(&mdev->md_io_mutex);
3686 static void debug_drbd_uuid(struct drbd_conf *mdev, enum drbd_uuid_index index)
3688 static char *uuid_str[UI_EXTENDED_SIZE] = {
3689 [UI_CURRENT] = "CURRENT",
3690 [UI_BITMAP] = "BITMAP",
3691 [UI_HISTORY_START] = "HISTORY_START",
3692 [UI_HISTORY_END] = "HISTORY_END",
3694 [UI_FLAGS] = "FLAGS",
3697 if (index >= UI_EXTENDED_SIZE) {
3698 dev_warn(DEV, " uuid_index >= EXTENDED_SIZE\n");
3702 dynamic_dev_dbg(DEV, " uuid[%s] now %016llX\n",
3704 (unsigned long long)mdev->ldev->md.uuid[index]);
3709 * drbd_md_mark_dirty() - Mark meta data super block as dirty
3710 * @mdev: DRBD device.
3712 * Call this function if you change anything that should be written to
3713 * the meta-data super block. This function sets MD_DIRTY, and starts a
3714 * timer that ensures that within five seconds you have to call drbd_md_sync().
3717 void drbd_md_mark_dirty_(struct drbd_conf *mdev, unsigned int line, const char *func)
3719 if (!test_and_set_bit(MD_DIRTY, &mdev->flags)) {
3720 mod_timer(&mdev->md_sync_timer, jiffies + HZ);
3721 mdev->last_md_mark_dirty.line = line;
3722 mdev->last_md_mark_dirty.func = func;
3726 void drbd_md_mark_dirty(struct drbd_conf *mdev)
3728 if (!test_and_set_bit(MD_DIRTY, &mdev->flags))
3729 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
3733 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
3737 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++) {
3738 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
3739 debug_drbd_uuid(mdev, i+1);
3743 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3745 if (idx == UI_CURRENT) {
3746 if (mdev->state.role == R_PRIMARY)
3751 drbd_set_ed_uuid(mdev, val);
3754 mdev->ldev->md.uuid[idx] = val;
3755 debug_drbd_uuid(mdev, idx);
3756 drbd_md_mark_dirty(mdev);
3760 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3762 if (mdev->ldev->md.uuid[idx]) {
3763 drbd_uuid_move_history(mdev);
3764 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
3765 debug_drbd_uuid(mdev, UI_HISTORY_START);
3767 _drbd_uuid_set(mdev, idx, val);
3771 * drbd_uuid_new_current() - Creates a new current UUID
3772 * @mdev: DRBD device.
3774 * Creates a new current UUID, and rotates the old current UUID into
3775 * the bitmap slot. Causes an incremental resync upon next connect.
3777 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
3781 dev_info(DEV, "Creating new current UUID\n");
3782 D_ASSERT(mdev->ldev->md.uuid[UI_BITMAP] == 0);
3783 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
3784 debug_drbd_uuid(mdev, UI_BITMAP);
3786 get_random_bytes(&val, sizeof(u64));
3787 _drbd_uuid_set(mdev, UI_CURRENT, val);
3788 /* get it to stable storage _now_ */
3792 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
3794 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
3798 drbd_uuid_move_history(mdev);
3799 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
3800 mdev->ldev->md.uuid[UI_BITMAP] = 0;
3801 debug_drbd_uuid(mdev, UI_HISTORY_START);
3802 debug_drbd_uuid(mdev, UI_BITMAP);
3804 if (mdev->ldev->md.uuid[UI_BITMAP])
3805 dev_warn(DEV, "bm UUID already set");
3807 mdev->ldev->md.uuid[UI_BITMAP] = val;
3808 mdev->ldev->md.uuid[UI_BITMAP] &= ~((u64)1);
3810 debug_drbd_uuid(mdev, UI_BITMAP);
3812 drbd_md_mark_dirty(mdev);
3816 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3817 * @mdev: DRBD device.
3819 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
3821 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
3825 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3826 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
3828 drbd_bm_set_all(mdev);
3830 rv = drbd_bm_write(mdev);
3833 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
3844 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3845 * @mdev: DRBD device.
3847 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
3849 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
3853 drbd_resume_al(mdev);
3854 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3855 drbd_bm_clear_all(mdev);
3856 rv = drbd_bm_write(mdev);
3863 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3865 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
3868 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
3870 if (get_ldev(mdev)) {
3871 drbd_bm_lock(mdev, work->why);
3872 rv = work->io_fn(mdev);
3873 drbd_bm_unlock(mdev);
3877 clear_bit(BITMAP_IO, &mdev->flags);
3878 smp_mb__after_clear_bit();
3879 wake_up(&mdev->misc_wait);
3882 work->done(mdev, rv);
3884 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
3890 void drbd_ldev_destroy(struct drbd_conf *mdev)
3892 lc_destroy(mdev->resync);
3893 mdev->resync = NULL;
3894 lc_destroy(mdev->act_log);
3895 mdev->act_log = NULL;
3897 drbd_free_bc(mdev->ldev);
3898 mdev->ldev = NULL;);
3900 if (mdev->md_io_tmpp) {
3901 __free_page(mdev->md_io_tmpp);
3902 mdev->md_io_tmpp = NULL;
3904 clear_bit(GO_DISKLESS, &mdev->flags);
3907 static int w_go_diskless(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3909 D_ASSERT(mdev->state.disk == D_FAILED);
3910 /* we cannot assert local_cnt == 0 here, as get_ldev_if_state will
3911 * inc/dec it frequently. Once we are D_DISKLESS, no one will touch
3912 * the protected members anymore, though, so once put_ldev reaches zero
3913 * again, it will be safe to free them. */
3914 drbd_force_state(mdev, NS(disk, D_DISKLESS));
3918 void drbd_go_diskless(struct drbd_conf *mdev)
3920 D_ASSERT(mdev->state.disk == D_FAILED);
3921 if (!test_and_set_bit(GO_DISKLESS, &mdev->flags))
3922 drbd_queue_work(&mdev->data.work, &mdev->go_diskless);
3926 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
3927 * @mdev: DRBD device.
3928 * @io_fn: IO callback to be called when bitmap IO is possible
3929 * @done: callback to be called after the bitmap IO was performed
3930 * @why: Descriptive text of the reason for doing the IO
3932 * While IO on the bitmap happens we freeze application IO thus we ensure
3933 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
3934 * called from worker context. It MUST NOT be used while a previous such
3935 * work is still pending!
3937 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
3938 int (*io_fn)(struct drbd_conf *),
3939 void (*done)(struct drbd_conf *, int),
3942 D_ASSERT(current == mdev->worker.task);
3944 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
3945 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
3946 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
3947 if (mdev->bm_io_work.why)
3948 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
3949 why, mdev->bm_io_work.why);
3951 mdev->bm_io_work.io_fn = io_fn;
3952 mdev->bm_io_work.done = done;
3953 mdev->bm_io_work.why = why;
3955 spin_lock_irq(&mdev->req_lock);
3956 set_bit(BITMAP_IO, &mdev->flags);
3957 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
3958 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
3959 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
3961 spin_unlock_irq(&mdev->req_lock);
3965 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
3966 * @mdev: DRBD device.
3967 * @io_fn: IO callback to be called when bitmap IO is possible
3968 * @why: Descriptive text of the reason for doing the IO
3970 * freezes application IO while that the actual IO operations runs. This
3971 * functions MAY NOT be called from worker context.
3973 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why)
3977 D_ASSERT(current != mdev->worker.task);
3979 drbd_suspend_io(mdev);
3981 drbd_bm_lock(mdev, why);
3983 drbd_bm_unlock(mdev);
3985 drbd_resume_io(mdev);
3990 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3992 if ((mdev->ldev->md.flags & flag) != flag) {
3993 drbd_md_mark_dirty(mdev);
3994 mdev->ldev->md.flags |= flag;
3998 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
4000 if ((mdev->ldev->md.flags & flag) != 0) {
4001 drbd_md_mark_dirty(mdev);
4002 mdev->ldev->md.flags &= ~flag;
4005 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
4007 return (bdev->md.flags & flag) != 0;
4010 static void md_sync_timer_fn(unsigned long data)
4012 struct drbd_conf *mdev = (struct drbd_conf *) data;
4014 drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work);
4017 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused)
4019 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
4021 dev_warn(DEV, "last md_mark_dirty: %s:%u\n",
4022 mdev->last_md_mark_dirty.func, mdev->last_md_mark_dirty.line);
4028 #ifdef CONFIG_DRBD_FAULT_INJECTION
4029 /* Fault insertion support including random number generator shamelessly
4030 * stolen from kernel/rcutorture.c */
4031 struct fault_random_state {
4032 unsigned long state;
4033 unsigned long count;
4036 #define FAULT_RANDOM_MULT 39916801 /* prime */
4037 #define FAULT_RANDOM_ADD 479001701 /* prime */
4038 #define FAULT_RANDOM_REFRESH 10000
4041 * Crude but fast random-number generator. Uses a linear congruential
4042 * generator, with occasional help from get_random_bytes().
4044 static unsigned long
4045 _drbd_fault_random(struct fault_random_state *rsp)
4049 if (!rsp->count--) {
4050 get_random_bytes(&refresh, sizeof(refresh));
4051 rsp->state += refresh;
4052 rsp->count = FAULT_RANDOM_REFRESH;
4054 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
4055 return swahw32(rsp->state);
4059 _drbd_fault_str(unsigned int type) {
4060 static char *_faults[] = {
4061 [DRBD_FAULT_MD_WR] = "Meta-data write",
4062 [DRBD_FAULT_MD_RD] = "Meta-data read",
4063 [DRBD_FAULT_RS_WR] = "Resync write",
4064 [DRBD_FAULT_RS_RD] = "Resync read",
4065 [DRBD_FAULT_DT_WR] = "Data write",
4066 [DRBD_FAULT_DT_RD] = "Data read",
4067 [DRBD_FAULT_DT_RA] = "Data read ahead",
4068 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
4069 [DRBD_FAULT_AL_EE] = "EE allocation",
4070 [DRBD_FAULT_RECEIVE] = "receive data corruption",
4073 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
4077 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
4079 static struct fault_random_state rrs = {0, 0};
4081 unsigned int ret = (
4083 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
4084 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
4089 if (__ratelimit(&drbd_ratelimit_state))
4090 dev_warn(DEV, "***Simulating %s failure\n",
4091 _drbd_fault_str(type));
4098 const char *drbd_buildtag(void)
4100 /* DRBD built from external sources has here a reference to the
4101 git hash of the source code. */
4103 static char buildtag[38] = "\0uilt-in";
4105 if (buildtag[0] == 0) {
4106 #ifdef CONFIG_MODULES
4107 if (THIS_MODULE != NULL)
4108 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
4117 module_init(drbd_init)
4118 module_exit(drbd_cleanup)
4120 EXPORT_SYMBOL(drbd_conn_str);
4121 EXPORT_SYMBOL(drbd_role_str);
4122 EXPORT_SYMBOL(drbd_disk_str);
4123 EXPORT_SYMBOL(drbd_set_st_err_str);