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/smp_lock.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 int drbdd_init(struct drbd_thread *);
68 int drbd_worker(struct drbd_thread *);
69 int drbd_asender(struct drbd_thread *);
72 static int drbd_open(struct block_device *bdev, fmode_t mode);
73 static int drbd_release(struct gendisk *gd, fmode_t mode);
74 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused);
75 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
76 union drbd_state ns, enum chg_state_flags flags);
77 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused);
78 static void md_sync_timer_fn(unsigned long data);
79 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused);
81 MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, "
82 "Lars Ellenberg <lars@linbit.com>");
83 MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION);
84 MODULE_VERSION(REL_VERSION);
85 MODULE_LICENSE("GPL");
86 MODULE_PARM_DESC(minor_count, "Maximum number of drbd devices (1-255)");
87 MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR);
89 #include <linux/moduleparam.h>
90 /* allow_open_on_secondary */
91 MODULE_PARM_DESC(allow_oos, "DONT USE!");
92 /* thanks to these macros, if compiled into the kernel (not-module),
93 * this becomes the boot parameter drbd.minor_count */
94 module_param(minor_count, uint, 0444);
95 module_param(disable_sendpage, bool, 0644);
96 module_param(allow_oos, bool, 0);
97 module_param(cn_idx, uint, 0444);
98 module_param(proc_details, int, 0644);
100 #ifdef CONFIG_DRBD_FAULT_INJECTION
103 static int fault_count;
105 /* bitmap of enabled faults */
106 module_param(enable_faults, int, 0664);
107 /* fault rate % value - applies to all enabled faults */
108 module_param(fault_rate, int, 0664);
109 /* count of faults inserted */
110 module_param(fault_count, int, 0664);
111 /* bitmap of devices to insert faults on */
112 module_param(fault_devs, int, 0644);
115 /* module parameter, defined */
116 unsigned int minor_count = 32;
117 int disable_sendpage;
119 unsigned int cn_idx = CN_IDX_DRBD;
120 int proc_details; /* Detail level in proc drbd*/
122 /* Module parameter for setting the user mode helper program
123 * to run. Default is /sbin/drbdadm */
124 char usermode_helper[80] = "/sbin/drbdadm";
126 module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644);
128 /* in 2.6.x, our device mapping and config info contains our virtual gendisks
129 * as member "struct gendisk *vdisk;"
131 struct drbd_conf **minor_table;
133 struct kmem_cache *drbd_request_cache;
134 struct kmem_cache *drbd_ee_cache; /* epoch entries */
135 struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */
136 struct kmem_cache *drbd_al_ext_cache; /* activity log extents */
137 mempool_t *drbd_request_mempool;
138 mempool_t *drbd_ee_mempool;
140 /* I do not use a standard mempool, because:
141 1) I want to hand out the pre-allocated objects first.
142 2) I want to be able to interrupt sleeping allocation with a signal.
143 Note: This is a single linked list, the next pointer is the private
144 member of struct page.
146 struct page *drbd_pp_pool;
147 spinlock_t drbd_pp_lock;
149 wait_queue_head_t drbd_pp_wait;
151 DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5);
153 static const struct block_device_operations drbd_ops = {
154 .owner = THIS_MODULE,
156 .release = drbd_release,
159 #define ARRY_SIZE(A) (sizeof(A)/sizeof(A[0]))
162 /* When checking with sparse, and this is an inline function, sparse will
163 give tons of false positives. When this is a real functions sparse works.
165 int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
169 atomic_inc(&mdev->local_cnt);
170 io_allowed = (mdev->state.disk >= mins);
172 if (atomic_dec_and_test(&mdev->local_cnt))
173 wake_up(&mdev->misc_wait);
181 * DOC: The transfer log
183 * The transfer log is a single linked list of &struct drbd_tl_epoch objects.
184 * mdev->newest_tle points to the head, mdev->oldest_tle points to the tail
185 * of the list. There is always at least one &struct drbd_tl_epoch object.
187 * Each &struct drbd_tl_epoch has a circular double linked list of requests
190 static int tl_init(struct drbd_conf *mdev)
192 struct drbd_tl_epoch *b;
194 /* during device minor initialization, we may well use GFP_KERNEL */
195 b = kmalloc(sizeof(struct drbd_tl_epoch), GFP_KERNEL);
198 INIT_LIST_HEAD(&b->requests);
199 INIT_LIST_HEAD(&b->w.list);
203 b->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
205 mdev->oldest_tle = b;
206 mdev->newest_tle = b;
207 INIT_LIST_HEAD(&mdev->out_of_sequence_requests);
209 mdev->tl_hash = NULL;
215 static void tl_cleanup(struct drbd_conf *mdev)
217 D_ASSERT(mdev->oldest_tle == mdev->newest_tle);
218 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
219 kfree(mdev->oldest_tle);
220 mdev->oldest_tle = NULL;
221 kfree(mdev->unused_spare_tle);
222 mdev->unused_spare_tle = NULL;
223 kfree(mdev->tl_hash);
224 mdev->tl_hash = NULL;
229 * _tl_add_barrier() - Adds a barrier to the transfer log
230 * @mdev: DRBD device.
231 * @new: Barrier to be added before the current head of the TL.
233 * The caller must hold the req_lock.
235 void _tl_add_barrier(struct drbd_conf *mdev, struct drbd_tl_epoch *new)
237 struct drbd_tl_epoch *newest_before;
239 INIT_LIST_HEAD(&new->requests);
240 INIT_LIST_HEAD(&new->w.list);
241 new->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
245 newest_before = mdev->newest_tle;
246 /* never send a barrier number == 0, because that is special-cased
247 * when using TCQ for our write ordering code */
248 new->br_number = (newest_before->br_number+1) ?: 1;
249 if (mdev->newest_tle != new) {
250 mdev->newest_tle->next = new;
251 mdev->newest_tle = new;
256 * tl_release() - Free or recycle the oldest &struct drbd_tl_epoch object of the TL
257 * @mdev: DRBD device.
258 * @barrier_nr: Expected identifier of the DRBD write barrier packet.
259 * @set_size: Expected number of requests before that barrier.
261 * In case the passed barrier_nr or set_size does not match the oldest
262 * &struct drbd_tl_epoch objects this function will cause a termination
265 void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
266 unsigned int set_size)
268 struct drbd_tl_epoch *b, *nob; /* next old barrier */
269 struct list_head *le, *tle;
270 struct drbd_request *r;
272 spin_lock_irq(&mdev->req_lock);
274 b = mdev->oldest_tle;
276 /* first some paranoia code */
278 dev_err(DEV, "BAD! BarrierAck #%u received, but no epoch in tl!?\n",
282 if (b->br_number != barrier_nr) {
283 dev_err(DEV, "BAD! BarrierAck #%u received, expected #%u!\n",
284 barrier_nr, b->br_number);
287 if (b->n_req != set_size) {
288 dev_err(DEV, "BAD! BarrierAck #%u received with n_req=%u, expected n_req=%u!\n",
289 barrier_nr, set_size, b->n_req);
293 /* Clean up list of requests processed during current epoch */
294 list_for_each_safe(le, tle, &b->requests) {
295 r = list_entry(le, struct drbd_request, tl_requests);
296 _req_mod(r, barrier_acked);
298 /* There could be requests on the list waiting for completion
299 of the write to the local disk. To avoid corruptions of
300 slab's data structures we have to remove the lists head.
302 Also there could have been a barrier ack out of sequence, overtaking
303 the write acks - which would be a bug and violating write ordering.
304 To not deadlock in case we lose connection while such requests are
305 still pending, we need some way to find them for the
306 _req_mode(connection_lost_while_pending).
308 These have been list_move'd to the out_of_sequence_requests list in
309 _req_mod(, barrier_acked) above.
311 list_del_init(&b->requests);
314 if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags)) {
315 _tl_add_barrier(mdev, b);
317 mdev->oldest_tle = nob;
318 /* if nob == NULL b was the only barrier, and becomes the new
319 barrier. Therefore mdev->oldest_tle points already to b */
321 D_ASSERT(nob != NULL);
322 mdev->oldest_tle = nob;
326 spin_unlock_irq(&mdev->req_lock);
327 dec_ap_pending(mdev);
332 spin_unlock_irq(&mdev->req_lock);
333 drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
338 * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL
339 * @mdev: DRBD device.
341 * This is called after the connection to the peer was lost. The storage covered
342 * by the requests on the transfer gets marked as our of sync. Called from the
343 * receiver thread and the worker thread.
345 void tl_clear(struct drbd_conf *mdev)
347 struct drbd_tl_epoch *b, *tmp;
348 struct list_head *le, *tle;
349 struct drbd_request *r;
350 int new_initial_bnr = net_random();
352 spin_lock_irq(&mdev->req_lock);
354 b = mdev->oldest_tle;
356 list_for_each_safe(le, tle, &b->requests) {
357 r = list_entry(le, struct drbd_request, tl_requests);
358 /* It would be nice to complete outside of spinlock.
359 * But this is easier for now. */
360 _req_mod(r, connection_lost_while_pending);
364 /* there could still be requests on that ring list,
365 * in case local io is still pending */
366 list_del(&b->requests);
368 /* dec_ap_pending corresponding to queue_barrier.
369 * the newest barrier may not have been queued yet,
370 * in which case w.cb is still NULL. */
372 dec_ap_pending(mdev);
374 if (b == mdev->newest_tle) {
375 /* recycle, but reinit! */
376 D_ASSERT(tmp == NULL);
377 INIT_LIST_HEAD(&b->requests);
378 INIT_LIST_HEAD(&b->w.list);
380 b->br_number = new_initial_bnr;
383 mdev->oldest_tle = b;
390 /* we expect this list to be empty. */
391 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
393 /* but just in case, clean it up anyways! */
394 list_for_each_safe(le, tle, &mdev->out_of_sequence_requests) {
395 r = list_entry(le, struct drbd_request, tl_requests);
396 /* It would be nice to complete outside of spinlock.
397 * But this is easier for now. */
398 _req_mod(r, connection_lost_while_pending);
401 /* ensure bit indicating barrier is required is clear */
402 clear_bit(CREATE_BARRIER, &mdev->flags);
404 spin_unlock_irq(&mdev->req_lock);
408 * cl_wide_st_chg() - TRUE if the state change is a cluster wide one
409 * @mdev: DRBD device.
410 * @os: old (current) state.
411 * @ns: new (wanted) state.
413 static int cl_wide_st_chg(struct drbd_conf *mdev,
414 union drbd_state os, union drbd_state ns)
416 return (os.conn >= C_CONNECTED && ns.conn >= C_CONNECTED &&
417 ((os.role != R_PRIMARY && ns.role == R_PRIMARY) ||
418 (os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
419 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S) ||
420 (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))) ||
421 (os.conn >= C_CONNECTED && ns.conn == C_DISCONNECTING) ||
422 (os.conn == C_CONNECTED && ns.conn == C_VERIFY_S);
425 int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f,
426 union drbd_state mask, union drbd_state val)
429 union drbd_state os, ns;
432 spin_lock_irqsave(&mdev->req_lock, flags);
434 ns.i = (os.i & ~mask.i) | val.i;
435 rv = _drbd_set_state(mdev, ns, f, NULL);
437 spin_unlock_irqrestore(&mdev->req_lock, flags);
443 * drbd_force_state() - Impose a change which happens outside our control on our state
444 * @mdev: DRBD device.
445 * @mask: mask of state bits to change.
446 * @val: value of new state bits.
448 void drbd_force_state(struct drbd_conf *mdev,
449 union drbd_state mask, union drbd_state val)
451 drbd_change_state(mdev, CS_HARD, mask, val);
454 static int is_valid_state(struct drbd_conf *mdev, union drbd_state ns);
455 static int is_valid_state_transition(struct drbd_conf *,
456 union drbd_state, union drbd_state);
457 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
458 union drbd_state ns, int *warn_sync_abort);
459 int drbd_send_state_req(struct drbd_conf *,
460 union drbd_state, union drbd_state);
462 static enum drbd_state_ret_codes _req_st_cond(struct drbd_conf *mdev,
463 union drbd_state mask, union drbd_state val)
465 union drbd_state os, ns;
469 if (test_and_clear_bit(CL_ST_CHG_SUCCESS, &mdev->flags))
470 return SS_CW_SUCCESS;
472 if (test_and_clear_bit(CL_ST_CHG_FAIL, &mdev->flags))
473 return SS_CW_FAILED_BY_PEER;
476 spin_lock_irqsave(&mdev->req_lock, flags);
478 ns.i = (os.i & ~mask.i) | val.i;
479 ns = sanitize_state(mdev, os, ns, NULL);
481 if (!cl_wide_st_chg(mdev, os, ns))
484 rv = is_valid_state(mdev, ns);
485 if (rv == SS_SUCCESS) {
486 rv = is_valid_state_transition(mdev, ns, os);
487 if (rv == SS_SUCCESS)
488 rv = 0; /* cont waiting, otherwise fail. */
491 spin_unlock_irqrestore(&mdev->req_lock, flags);
497 * drbd_req_state() - Perform an eventually cluster wide state change
498 * @mdev: DRBD device.
499 * @mask: mask of state bits to change.
500 * @val: value of new state bits.
503 * Should not be called directly, use drbd_request_state() or
504 * _drbd_request_state().
506 static int drbd_req_state(struct drbd_conf *mdev,
507 union drbd_state mask, union drbd_state val,
508 enum chg_state_flags f)
510 struct completion done;
512 union drbd_state os, ns;
515 init_completion(&done);
517 if (f & CS_SERIALIZE)
518 mutex_lock(&mdev->state_mutex);
520 spin_lock_irqsave(&mdev->req_lock, flags);
522 ns.i = (os.i & ~mask.i) | val.i;
523 ns = sanitize_state(mdev, os, ns, NULL);
525 if (cl_wide_st_chg(mdev, os, ns)) {
526 rv = is_valid_state(mdev, ns);
527 if (rv == SS_SUCCESS)
528 rv = is_valid_state_transition(mdev, ns, os);
529 spin_unlock_irqrestore(&mdev->req_lock, flags);
531 if (rv < SS_SUCCESS) {
533 print_st_err(mdev, os, ns, rv);
537 drbd_state_lock(mdev);
538 if (!drbd_send_state_req(mdev, mask, val)) {
539 drbd_state_unlock(mdev);
540 rv = SS_CW_FAILED_BY_PEER;
542 print_st_err(mdev, os, ns, rv);
546 wait_event(mdev->state_wait,
547 (rv = _req_st_cond(mdev, mask, val)));
549 if (rv < SS_SUCCESS) {
550 drbd_state_unlock(mdev);
552 print_st_err(mdev, os, ns, rv);
555 spin_lock_irqsave(&mdev->req_lock, flags);
557 ns.i = (os.i & ~mask.i) | val.i;
558 rv = _drbd_set_state(mdev, ns, f, &done);
559 drbd_state_unlock(mdev);
561 rv = _drbd_set_state(mdev, ns, f, &done);
564 spin_unlock_irqrestore(&mdev->req_lock, flags);
566 if (f & CS_WAIT_COMPLETE && rv == SS_SUCCESS) {
567 D_ASSERT(current != mdev->worker.task);
568 wait_for_completion(&done);
572 if (f & CS_SERIALIZE)
573 mutex_unlock(&mdev->state_mutex);
579 * _drbd_request_state() - Request a state change (with flags)
580 * @mdev: DRBD device.
581 * @mask: mask of state bits to change.
582 * @val: value of new state bits.
585 * Cousin of drbd_request_state(), useful with the CS_WAIT_COMPLETE
586 * flag, or when logging of failed state change requests is not desired.
588 int _drbd_request_state(struct drbd_conf *mdev, union drbd_state mask,
589 union drbd_state val, enum chg_state_flags f)
593 wait_event(mdev->state_wait,
594 (rv = drbd_req_state(mdev, mask, val, f)) != SS_IN_TRANSIENT_STATE);
599 static void print_st(struct drbd_conf *mdev, char *name, union drbd_state ns)
601 dev_err(DEV, " %s = { cs:%s ro:%s/%s ds:%s/%s %c%c%c%c }\n",
603 drbd_conn_str(ns.conn),
604 drbd_role_str(ns.role),
605 drbd_role_str(ns.peer),
606 drbd_disk_str(ns.disk),
607 drbd_disk_str(ns.pdsk),
609 ns.aftr_isp ? 'a' : '-',
610 ns.peer_isp ? 'p' : '-',
611 ns.user_isp ? 'u' : '-'
615 void print_st_err(struct drbd_conf *mdev,
616 union drbd_state os, union drbd_state ns, int err)
618 if (err == SS_IN_TRANSIENT_STATE)
620 dev_err(DEV, "State change failed: %s\n", drbd_set_st_err_str(err));
621 print_st(mdev, " state", os);
622 print_st(mdev, "wanted", ns);
626 #define drbd_peer_str drbd_role_str
627 #define drbd_pdsk_str drbd_disk_str
629 #define drbd_susp_str(A) ((A) ? "1" : "0")
630 #define drbd_aftr_isp_str(A) ((A) ? "1" : "0")
631 #define drbd_peer_isp_str(A) ((A) ? "1" : "0")
632 #define drbd_user_isp_str(A) ((A) ? "1" : "0")
635 ({ if (ns.A != os.A) { \
636 pbp += sprintf(pbp, #A "( %s -> %s ) ", \
637 drbd_##A##_str(os.A), \
638 drbd_##A##_str(ns.A)); \
642 * is_valid_state() - Returns an SS_ error code if ns is not valid
643 * @mdev: DRBD device.
644 * @ns: State to consider.
646 static int is_valid_state(struct drbd_conf *mdev, union drbd_state ns)
648 /* See drbd_state_sw_errors in drbd_strings.c */
650 enum drbd_fencing_p fp;
654 if (get_ldev(mdev)) {
655 fp = mdev->ldev->dc.fencing;
659 if (get_net_conf(mdev)) {
660 if (!mdev->net_conf->two_primaries &&
661 ns.role == R_PRIMARY && ns.peer == R_PRIMARY)
662 rv = SS_TWO_PRIMARIES;
667 /* already found a reason to abort */;
668 else if (ns.role == R_SECONDARY && mdev->open_cnt)
669 rv = SS_DEVICE_IN_USE;
671 else if (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.disk < D_UP_TO_DATE)
672 rv = SS_NO_UP_TO_DATE_DISK;
674 else if (fp >= FP_RESOURCE &&
675 ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk >= D_UNKNOWN)
678 else if (ns.role == R_PRIMARY && ns.disk <= D_INCONSISTENT && ns.pdsk <= D_INCONSISTENT)
679 rv = SS_NO_UP_TO_DATE_DISK;
681 else if (ns.conn > C_CONNECTED && ns.disk < D_INCONSISTENT)
682 rv = SS_NO_LOCAL_DISK;
684 else if (ns.conn > C_CONNECTED && ns.pdsk < D_INCONSISTENT)
685 rv = SS_NO_REMOTE_DISK;
687 else if (ns.conn > C_CONNECTED && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE)
688 rv = SS_NO_UP_TO_DATE_DISK;
690 else if ((ns.conn == C_CONNECTED ||
691 ns.conn == C_WF_BITMAP_S ||
692 ns.conn == C_SYNC_SOURCE ||
693 ns.conn == C_PAUSED_SYNC_S) &&
694 ns.disk == D_OUTDATED)
695 rv = SS_CONNECTED_OUTDATES;
697 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
698 (mdev->sync_conf.verify_alg[0] == 0))
699 rv = SS_NO_VERIFY_ALG;
701 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
702 mdev->agreed_pro_version < 88)
703 rv = SS_NOT_SUPPORTED;
709 * is_valid_state_transition() - Returns an SS_ error code if the state transition is not possible
710 * @mdev: DRBD device.
714 static int is_valid_state_transition(struct drbd_conf *mdev,
715 union drbd_state ns, union drbd_state os)
719 if ((ns.conn == C_STARTING_SYNC_T || ns.conn == C_STARTING_SYNC_S) &&
720 os.conn > C_CONNECTED)
721 rv = SS_RESYNC_RUNNING;
723 if (ns.conn == C_DISCONNECTING && os.conn == C_STANDALONE)
724 rv = SS_ALREADY_STANDALONE;
726 if (ns.disk > D_ATTACHING && os.disk == D_DISKLESS)
729 if (ns.conn == C_WF_CONNECTION && os.conn < C_UNCONNECTED)
730 rv = SS_NO_NET_CONFIG;
732 if (ns.disk == D_OUTDATED && os.disk < D_OUTDATED && os.disk != D_ATTACHING)
733 rv = SS_LOWER_THAN_OUTDATED;
735 if (ns.conn == C_DISCONNECTING && os.conn == C_UNCONNECTED)
736 rv = SS_IN_TRANSIENT_STATE;
738 if (ns.conn == os.conn && ns.conn == C_WF_REPORT_PARAMS)
739 rv = SS_IN_TRANSIENT_STATE;
741 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && os.conn < C_CONNECTED)
742 rv = SS_NEED_CONNECTION;
744 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
745 ns.conn != os.conn && os.conn > C_CONNECTED)
746 rv = SS_RESYNC_RUNNING;
748 if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) &&
749 os.conn < C_CONNECTED)
750 rv = SS_NEED_CONNECTION;
756 * sanitize_state() - Resolves implicitly necessary additional changes to a state transition
757 * @mdev: DRBD device.
762 * When we loose connection, we have to set the state of the peers disk (pdsk)
763 * to D_UNKNOWN. This rule and many more along those lines are in this function.
765 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
766 union drbd_state ns, int *warn_sync_abort)
768 enum drbd_fencing_p fp;
771 if (get_ldev(mdev)) {
772 fp = mdev->ldev->dc.fencing;
776 /* Disallow Network errors to configure a device's network part */
777 if ((ns.conn >= C_TIMEOUT && ns.conn <= C_TEAR_DOWN) &&
778 os.conn <= C_DISCONNECTING)
781 /* After a network error (+C_TEAR_DOWN) only C_UNCONNECTED or C_DISCONNECTING can follow */
782 if (os.conn >= C_TIMEOUT && os.conn <= C_TEAR_DOWN &&
783 ns.conn != C_UNCONNECTED && ns.conn != C_DISCONNECTING)
786 /* After C_DISCONNECTING only C_STANDALONE may follow */
787 if (os.conn == C_DISCONNECTING && ns.conn != C_STANDALONE)
790 if (ns.conn < C_CONNECTED) {
793 if (ns.pdsk > D_UNKNOWN || ns.pdsk < D_INCONSISTENT)
797 /* Clear the aftr_isp when becoming unconfigured */
798 if (ns.conn == C_STANDALONE && ns.disk == D_DISKLESS && ns.role == R_SECONDARY)
801 if (ns.conn <= C_DISCONNECTING && ns.disk == D_DISKLESS)
804 /* Abort resync if a disk fails/detaches */
805 if (os.conn > C_CONNECTED && ns.conn > C_CONNECTED &&
806 (ns.disk <= D_FAILED || ns.pdsk <= D_FAILED)) {
808 *warn_sync_abort = 1;
809 ns.conn = C_CONNECTED;
812 if (ns.conn >= C_CONNECTED &&
813 ((ns.disk == D_CONSISTENT || ns.disk == D_OUTDATED) ||
814 (ns.disk == D_NEGOTIATING && ns.conn == C_WF_BITMAP_T))) {
817 case C_PAUSED_SYNC_T:
818 ns.disk = D_OUTDATED;
823 case C_PAUSED_SYNC_S:
824 ns.disk = D_UP_TO_DATE;
827 ns.disk = D_INCONSISTENT;
828 dev_warn(DEV, "Implicitly set disk state Inconsistent!\n");
831 if (os.disk == D_OUTDATED && ns.disk == D_UP_TO_DATE)
832 dev_warn(DEV, "Implicitly set disk from Outdated to UpToDate\n");
835 if (ns.conn >= C_CONNECTED &&
836 (ns.pdsk == D_CONSISTENT || ns.pdsk == D_OUTDATED)) {
840 case C_PAUSED_SYNC_T:
842 ns.pdsk = D_UP_TO_DATE;
845 case C_PAUSED_SYNC_S:
846 /* remap any consistent state to D_OUTDATED,
847 * but disallow "upgrade" of not even consistent states.
850 (D_DISKLESS < os.pdsk && os.pdsk < D_OUTDATED)
851 ? os.pdsk : D_OUTDATED;
854 ns.pdsk = D_INCONSISTENT;
855 dev_warn(DEV, "Implicitly set pdsk Inconsistent!\n");
858 if (os.pdsk == D_OUTDATED && ns.pdsk == D_UP_TO_DATE)
859 dev_warn(DEV, "Implicitly set pdsk from Outdated to UpToDate\n");
862 /* Connection breaks down before we finished "Negotiating" */
863 if (ns.conn < C_CONNECTED && ns.disk == D_NEGOTIATING &&
864 get_ldev_if_state(mdev, D_NEGOTIATING)) {
865 if (mdev->ed_uuid == mdev->ldev->md.uuid[UI_CURRENT]) {
866 ns.disk = mdev->new_state_tmp.disk;
867 ns.pdsk = mdev->new_state_tmp.pdsk;
869 dev_alert(DEV, "Connection lost while negotiating, no data!\n");
870 ns.disk = D_DISKLESS;
876 if (fp == FP_STONITH &&
877 (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk > D_OUTDATED) &&
878 !(os.role == R_PRIMARY && os.conn < C_CONNECTED && os.pdsk > D_OUTDATED))
881 if (ns.aftr_isp || ns.peer_isp || ns.user_isp) {
882 if (ns.conn == C_SYNC_SOURCE)
883 ns.conn = C_PAUSED_SYNC_S;
884 if (ns.conn == C_SYNC_TARGET)
885 ns.conn = C_PAUSED_SYNC_T;
887 if (ns.conn == C_PAUSED_SYNC_S)
888 ns.conn = C_SYNC_SOURCE;
889 if (ns.conn == C_PAUSED_SYNC_T)
890 ns.conn = C_SYNC_TARGET;
896 /* helper for __drbd_set_state */
897 static void set_ov_position(struct drbd_conf *mdev, enum drbd_conns cs)
899 if (cs == C_VERIFY_T) {
900 /* starting online verify from an arbitrary position
901 * does not fit well into the existing protocol.
902 * on C_VERIFY_T, we initialize ov_left and friends
903 * implicitly in receive_DataRequest once the
904 * first P_OV_REQUEST is received */
905 mdev->ov_start_sector = ~(sector_t)0;
907 unsigned long bit = BM_SECT_TO_BIT(mdev->ov_start_sector);
908 if (bit >= mdev->rs_total)
909 mdev->ov_start_sector =
910 BM_BIT_TO_SECT(mdev->rs_total - 1);
911 mdev->ov_position = mdev->ov_start_sector;
916 * __drbd_set_state() - Set a new DRBD state
917 * @mdev: DRBD device.
920 * @done: Optional completion, that will get completed after the after_state_ch() finished
922 * Caller needs to hold req_lock, and global_state_lock. Do not call directly.
924 int __drbd_set_state(struct drbd_conf *mdev,
925 union drbd_state ns, enum chg_state_flags flags,
926 struct completion *done)
930 int warn_sync_abort = 0;
931 struct after_state_chg_work *ascw;
935 ns = sanitize_state(mdev, os, ns, &warn_sync_abort);
938 return SS_NOTHING_TO_DO;
940 if (!(flags & CS_HARD)) {
941 /* pre-state-change checks ; only look at ns */
942 /* See drbd_state_sw_errors in drbd_strings.c */
944 rv = is_valid_state(mdev, ns);
945 if (rv < SS_SUCCESS) {
946 /* If the old state was illegal as well, then let
949 if (is_valid_state(mdev, os) == rv) {
950 dev_err(DEV, "Considering state change from bad state. "
951 "Error would be: '%s'\n",
952 drbd_set_st_err_str(rv));
953 print_st(mdev, "old", os);
954 print_st(mdev, "new", ns);
955 rv = is_valid_state_transition(mdev, ns, os);
958 rv = is_valid_state_transition(mdev, ns, os);
961 if (rv < SS_SUCCESS) {
962 if (flags & CS_VERBOSE)
963 print_st_err(mdev, os, ns, rv);
968 dev_warn(DEV, "Resync aborted.\n");
983 dev_info(DEV, "%s\n", pb);
986 /* solve the race between becoming unconfigured,
987 * worker doing the cleanup, and
988 * admin reconfiguring us:
989 * on (re)configure, first set CONFIG_PENDING,
990 * then wait for a potentially exiting worker,
991 * start the worker, and schedule one no_op.
992 * then proceed with configuration.
994 if (ns.disk == D_DISKLESS &&
995 ns.conn == C_STANDALONE &&
996 ns.role == R_SECONDARY &&
997 !test_and_set_bit(CONFIG_PENDING, &mdev->flags))
998 set_bit(DEVICE_DYING, &mdev->flags);
1000 mdev->state.i = ns.i;
1001 wake_up(&mdev->misc_wait);
1002 wake_up(&mdev->state_wait);
1004 /* post-state-change actions */
1005 if (os.conn >= C_SYNC_SOURCE && ns.conn <= C_CONNECTED) {
1006 set_bit(STOP_SYNC_TIMER, &mdev->flags);
1007 mod_timer(&mdev->resync_timer, jiffies);
1010 /* aborted verify run. log the last position */
1011 if ((os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) &&
1012 ns.conn < C_CONNECTED) {
1013 mdev->ov_start_sector =
1014 BM_BIT_TO_SECT(mdev->rs_total - mdev->ov_left);
1015 dev_info(DEV, "Online Verify reached sector %llu\n",
1016 (unsigned long long)mdev->ov_start_sector);
1019 if ((os.conn == C_PAUSED_SYNC_T || os.conn == C_PAUSED_SYNC_S) &&
1020 (ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)) {
1021 dev_info(DEV, "Syncer continues.\n");
1022 mdev->rs_paused += (long)jiffies-(long)mdev->rs_mark_time;
1023 if (ns.conn == C_SYNC_TARGET) {
1024 if (!test_and_clear_bit(STOP_SYNC_TIMER, &mdev->flags))
1025 mod_timer(&mdev->resync_timer, jiffies);
1026 /* This if (!test_bit) is only needed for the case
1027 that a device that has ceased to used its timer,
1028 i.e. it is already in drbd_resync_finished() gets
1029 paused and resumed. */
1033 if ((os.conn == C_SYNC_TARGET || os.conn == C_SYNC_SOURCE) &&
1034 (ns.conn == C_PAUSED_SYNC_T || ns.conn == C_PAUSED_SYNC_S)) {
1035 dev_info(DEV, "Resync suspended\n");
1036 mdev->rs_mark_time = jiffies;
1037 if (ns.conn == C_PAUSED_SYNC_T)
1038 set_bit(STOP_SYNC_TIMER, &mdev->flags);
1041 if (os.conn == C_CONNECTED &&
1042 (ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T)) {
1043 mdev->ov_position = 0;
1045 mdev->rs_mark_left = drbd_bm_bits(mdev);
1046 if (mdev->agreed_pro_version >= 90)
1047 set_ov_position(mdev, ns.conn);
1049 mdev->ov_start_sector = 0;
1050 mdev->ov_left = mdev->rs_total
1051 - BM_SECT_TO_BIT(mdev->ov_position);
1053 mdev->rs_mark_time = jiffies;
1054 mdev->ov_last_oos_size = 0;
1055 mdev->ov_last_oos_start = 0;
1057 if (ns.conn == C_VERIFY_S) {
1058 dev_info(DEV, "Starting Online Verify from sector %llu\n",
1059 (unsigned long long)mdev->ov_position);
1060 mod_timer(&mdev->resync_timer, jiffies);
1064 if (get_ldev(mdev)) {
1065 u32 mdf = mdev->ldev->md.flags & ~(MDF_CONSISTENT|MDF_PRIMARY_IND|
1066 MDF_CONNECTED_IND|MDF_WAS_UP_TO_DATE|
1067 MDF_PEER_OUT_DATED|MDF_CRASHED_PRIMARY);
1069 if (test_bit(CRASHED_PRIMARY, &mdev->flags))
1070 mdf |= MDF_CRASHED_PRIMARY;
1071 if (mdev->state.role == R_PRIMARY ||
1072 (mdev->state.pdsk < D_INCONSISTENT && mdev->state.peer == R_PRIMARY))
1073 mdf |= MDF_PRIMARY_IND;
1074 if (mdev->state.conn > C_WF_REPORT_PARAMS)
1075 mdf |= MDF_CONNECTED_IND;
1076 if (mdev->state.disk > D_INCONSISTENT)
1077 mdf |= MDF_CONSISTENT;
1078 if (mdev->state.disk > D_OUTDATED)
1079 mdf |= MDF_WAS_UP_TO_DATE;
1080 if (mdev->state.pdsk <= D_OUTDATED && mdev->state.pdsk >= D_INCONSISTENT)
1081 mdf |= MDF_PEER_OUT_DATED;
1082 if (mdf != mdev->ldev->md.flags) {
1083 mdev->ldev->md.flags = mdf;
1084 drbd_md_mark_dirty(mdev);
1086 if (os.disk < D_CONSISTENT && ns.disk >= D_CONSISTENT)
1087 drbd_set_ed_uuid(mdev, mdev->ldev->md.uuid[UI_CURRENT]);
1091 /* Peer was forced D_UP_TO_DATE & R_PRIMARY, consider to resync */
1092 if (os.disk == D_INCONSISTENT && os.pdsk == D_INCONSISTENT &&
1093 os.peer == R_SECONDARY && ns.peer == R_PRIMARY)
1094 set_bit(CONSIDER_RESYNC, &mdev->flags);
1096 /* Receiver should clean up itself */
1097 if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING)
1098 drbd_thread_stop_nowait(&mdev->receiver);
1100 /* Now the receiver finished cleaning up itself, it should die */
1101 if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE)
1102 drbd_thread_stop_nowait(&mdev->receiver);
1104 /* Upon network failure, we need to restart the receiver. */
1105 if (os.conn > C_TEAR_DOWN &&
1106 ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT)
1107 drbd_thread_restart_nowait(&mdev->receiver);
1109 ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC);
1113 ascw->flags = flags;
1114 ascw->w.cb = w_after_state_ch;
1116 drbd_queue_work(&mdev->data.work, &ascw->w);
1118 dev_warn(DEV, "Could not kmalloc an ascw\n");
1124 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused)
1126 struct after_state_chg_work *ascw =
1127 container_of(w, struct after_state_chg_work, w);
1128 after_state_ch(mdev, ascw->os, ascw->ns, ascw->flags);
1129 if (ascw->flags & CS_WAIT_COMPLETE) {
1130 D_ASSERT(ascw->done != NULL);
1131 complete(ascw->done);
1138 static void abw_start_sync(struct drbd_conf *mdev, int rv)
1141 dev_err(DEV, "Writing the bitmap failed not starting resync.\n");
1142 _drbd_request_state(mdev, NS(conn, C_CONNECTED), CS_VERBOSE);
1146 switch (mdev->state.conn) {
1147 case C_STARTING_SYNC_T:
1148 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE);
1150 case C_STARTING_SYNC_S:
1151 drbd_start_resync(mdev, C_SYNC_SOURCE);
1157 * after_state_ch() - Perform after state change actions that may sleep
1158 * @mdev: DRBD device.
1163 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
1164 union drbd_state ns, enum chg_state_flags flags)
1166 enum drbd_fencing_p fp;
1168 if (os.conn != C_CONNECTED && ns.conn == C_CONNECTED) {
1169 clear_bit(CRASHED_PRIMARY, &mdev->flags);
1171 mdev->p_uuid[UI_FLAGS] &= ~((u64)2);
1175 if (get_ldev(mdev)) {
1176 fp = mdev->ldev->dc.fencing;
1180 /* Inform userspace about the change... */
1181 drbd_bcast_state(mdev, ns);
1183 if (!(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE) &&
1184 (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE))
1185 drbd_khelper(mdev, "pri-on-incon-degr");
1187 /* Here we have the actions that are performed after a
1188 state change. This function might sleep */
1190 if (fp == FP_STONITH && ns.susp) {
1191 /* case1: The outdate peer handler is successful:
1192 * case2: The connection was established again: */
1193 if ((os.pdsk > D_OUTDATED && ns.pdsk <= D_OUTDATED) ||
1194 (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)) {
1196 spin_lock_irq(&mdev->req_lock);
1197 _drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL);
1198 spin_unlock_irq(&mdev->req_lock);
1201 /* Do not change the order of the if above and the two below... */
1202 if (os.pdsk == D_DISKLESS && ns.pdsk > D_DISKLESS) { /* attach on the peer */
1203 drbd_send_uuids(mdev);
1204 drbd_send_state(mdev);
1206 if (os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S)
1207 drbd_queue_bitmap_io(mdev, &drbd_send_bitmap, NULL, "send_bitmap (WFBitMapS)");
1209 /* Lost contact to peer's copy of the data */
1210 if ((os.pdsk >= D_INCONSISTENT &&
1211 os.pdsk != D_UNKNOWN &&
1212 os.pdsk != D_OUTDATED)
1213 && (ns.pdsk < D_INCONSISTENT ||
1214 ns.pdsk == D_UNKNOWN ||
1215 ns.pdsk == D_OUTDATED)) {
1216 kfree(mdev->p_uuid);
1217 mdev->p_uuid = NULL;
1218 if (get_ldev(mdev)) {
1219 if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) &&
1220 mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE)
1221 atomic_set(&mdev->new_c_uuid, 2);
1226 if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) {
1227 /* Diskless peer becomes primary or got connected do diskless, primary peer. */
1228 if (ns.peer == R_PRIMARY && mdev->ldev->md.uuid[UI_BITMAP] == 0)
1229 atomic_set(&mdev->new_c_uuid, 2);
1231 /* D_DISKLESS Peer becomes secondary */
1232 if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
1233 drbd_al_to_on_disk_bm(mdev);
1237 /* Last part of the attaching process ... */
1238 if (ns.conn >= C_CONNECTED &&
1239 os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
1240 kfree(mdev->p_uuid); /* We expect to receive up-to-date UUIDs soon. */
1241 mdev->p_uuid = NULL; /* ...to not use the old ones in the mean time */
1242 drbd_send_sizes(mdev, 0, 0); /* to start sync... */
1243 drbd_send_uuids(mdev);
1244 drbd_send_state(mdev);
1247 /* We want to pause/continue resync, tell peer. */
1248 if (ns.conn >= C_CONNECTED &&
1249 ((os.aftr_isp != ns.aftr_isp) ||
1250 (os.user_isp != ns.user_isp)))
1251 drbd_send_state(mdev);
1253 /* In case one of the isp bits got set, suspend other devices. */
1254 if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
1255 (ns.aftr_isp || ns.peer_isp || ns.user_isp))
1256 suspend_other_sg(mdev);
1258 /* Make sure the peer gets informed about eventual state
1259 changes (ISP bits) while we were in WFReportParams. */
1260 if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
1261 drbd_send_state(mdev);
1263 /* We are in the progress to start a full sync... */
1264 if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
1265 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S))
1266 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, &abw_start_sync, "set_n_write from StartingSync");
1268 /* We are invalidating our self... */
1269 if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED &&
1270 os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT)
1271 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL, "set_n_write from invalidate");
1273 if (os.disk > D_FAILED && ns.disk == D_FAILED) {
1274 enum drbd_io_error_p eh;
1277 if (get_ldev_if_state(mdev, D_FAILED)) {
1278 eh = mdev->ldev->dc.on_io_error;
1282 drbd_rs_cancel_all(mdev);
1283 /* since get_ldev() only works as long as disk>=D_INCONSISTENT,
1284 and it is D_DISKLESS here, local_cnt can only go down, it can
1285 not increase... It will reach zero */
1286 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1288 mdev->rs_failed = 0;
1289 atomic_set(&mdev->rs_pending_cnt, 0);
1291 spin_lock_irq(&mdev->req_lock);
1292 _drbd_set_state(_NS(mdev, disk, D_DISKLESS), CS_HARD, NULL);
1293 spin_unlock_irq(&mdev->req_lock);
1295 if (eh == EP_CALL_HELPER)
1296 drbd_khelper(mdev, "local-io-error");
1299 if (os.disk > D_DISKLESS && ns.disk == D_DISKLESS) {
1301 if (os.disk == D_FAILED) /* && ns.disk == D_DISKLESS*/ {
1302 if (drbd_send_state(mdev))
1303 dev_warn(DEV, "Notified peer that my disk is broken.\n");
1305 dev_err(DEV, "Sending state in drbd_io_error() failed\n");
1308 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1309 lc_destroy(mdev->resync);
1310 mdev->resync = NULL;
1311 lc_destroy(mdev->act_log);
1312 mdev->act_log = NULL;
1314 drbd_free_bc(mdev->ldev);
1315 mdev->ldev = NULL;);
1317 if (mdev->md_io_tmpp)
1318 __free_page(mdev->md_io_tmpp);
1321 /* Disks got bigger while they were detached */
1322 if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
1323 test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) {
1324 if (ns.conn == C_CONNECTED)
1325 resync_after_online_grow(mdev);
1328 /* A resync finished or aborted, wake paused devices... */
1329 if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) ||
1330 (os.peer_isp && !ns.peer_isp) ||
1331 (os.user_isp && !ns.user_isp))
1332 resume_next_sg(mdev);
1334 /* Upon network connection, we need to start the receiver */
1335 if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED)
1336 drbd_thread_start(&mdev->receiver);
1338 /* Terminate worker thread if we are unconfigured - it will be
1339 restarted as needed... */
1340 if (ns.disk == D_DISKLESS &&
1341 ns.conn == C_STANDALONE &&
1342 ns.role == R_SECONDARY) {
1343 if (os.aftr_isp != ns.aftr_isp)
1344 resume_next_sg(mdev);
1345 /* set in __drbd_set_state, unless CONFIG_PENDING was set */
1346 if (test_bit(DEVICE_DYING, &mdev->flags))
1347 drbd_thread_stop_nowait(&mdev->worker);
1353 static int w_new_current_uuid(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1355 if (get_ldev(mdev)) {
1356 drbd_uuid_new_current(mdev);
1357 drbd_send_uuids(mdev);
1361 atomic_dec(&mdev->new_c_uuid);
1362 wake_up(&mdev->misc_wait);
1367 static int drbd_thread_setup(void *arg)
1369 struct drbd_thread *thi = (struct drbd_thread *) arg;
1370 struct drbd_conf *mdev = thi->mdev;
1371 unsigned long flags;
1375 retval = thi->function(thi);
1377 spin_lock_irqsave(&thi->t_lock, flags);
1379 /* if the receiver has been "Exiting", the last thing it did
1380 * was set the conn state to "StandAlone",
1381 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
1382 * and receiver thread will be "started".
1383 * drbd_thread_start needs to set "Restarting" in that case.
1384 * t_state check and assignment needs to be within the same spinlock,
1385 * so either thread_start sees Exiting, and can remap to Restarting,
1386 * or thread_start see None, and can proceed as normal.
1389 if (thi->t_state == Restarting) {
1390 dev_info(DEV, "Restarting %s\n", current->comm);
1391 thi->t_state = Running;
1392 spin_unlock_irqrestore(&thi->t_lock, flags);
1397 thi->t_state = None;
1399 complete(&thi->stop);
1400 spin_unlock_irqrestore(&thi->t_lock, flags);
1402 dev_info(DEV, "Terminating %s\n", current->comm);
1404 /* Release mod reference taken when thread was started */
1405 module_put(THIS_MODULE);
1409 static void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi,
1410 int (*func) (struct drbd_thread *))
1412 spin_lock_init(&thi->t_lock);
1414 thi->t_state = None;
1415 thi->function = func;
1419 int drbd_thread_start(struct drbd_thread *thi)
1421 struct drbd_conf *mdev = thi->mdev;
1422 struct task_struct *nt;
1423 unsigned long flags;
1426 thi == &mdev->receiver ? "receiver" :
1427 thi == &mdev->asender ? "asender" :
1428 thi == &mdev->worker ? "worker" : "NONSENSE";
1430 /* is used from state engine doing drbd_thread_stop_nowait,
1431 * while holding the req lock irqsave */
1432 spin_lock_irqsave(&thi->t_lock, flags);
1434 switch (thi->t_state) {
1436 dev_info(DEV, "Starting %s thread (from %s [%d])\n",
1437 me, current->comm, current->pid);
1439 /* Get ref on module for thread - this is released when thread exits */
1440 if (!try_module_get(THIS_MODULE)) {
1441 dev_err(DEV, "Failed to get module reference in drbd_thread_start\n");
1442 spin_unlock_irqrestore(&thi->t_lock, flags);
1446 init_completion(&thi->stop);
1447 D_ASSERT(thi->task == NULL);
1448 thi->reset_cpu_mask = 1;
1449 thi->t_state = Running;
1450 spin_unlock_irqrestore(&thi->t_lock, flags);
1451 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
1453 nt = kthread_create(drbd_thread_setup, (void *) thi,
1454 "drbd%d_%s", mdev_to_minor(mdev), me);
1457 dev_err(DEV, "Couldn't start thread\n");
1459 module_put(THIS_MODULE);
1462 spin_lock_irqsave(&thi->t_lock, flags);
1464 thi->t_state = Running;
1465 spin_unlock_irqrestore(&thi->t_lock, flags);
1466 wake_up_process(nt);
1469 thi->t_state = Restarting;
1470 dev_info(DEV, "Restarting %s thread (from %s [%d])\n",
1471 me, current->comm, current->pid);
1476 spin_unlock_irqrestore(&thi->t_lock, flags);
1484 void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
1486 unsigned long flags;
1488 enum drbd_thread_state ns = restart ? Restarting : Exiting;
1490 /* may be called from state engine, holding the req lock irqsave */
1491 spin_lock_irqsave(&thi->t_lock, flags);
1493 if (thi->t_state == None) {
1494 spin_unlock_irqrestore(&thi->t_lock, flags);
1496 drbd_thread_start(thi);
1500 if (thi->t_state != ns) {
1501 if (thi->task == NULL) {
1502 spin_unlock_irqrestore(&thi->t_lock, flags);
1508 init_completion(&thi->stop);
1509 if (thi->task != current)
1510 force_sig(DRBD_SIGKILL, thi->task);
1514 spin_unlock_irqrestore(&thi->t_lock, flags);
1517 wait_for_completion(&thi->stop);
1522 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
1523 * @mdev: DRBD device.
1525 * Forces all threads of a device onto the same CPU. This is beneficial for
1526 * DRBD's performance. May be overwritten by user's configuration.
1528 void drbd_calc_cpu_mask(struct drbd_conf *mdev)
1532 /* user override. */
1533 if (cpumask_weight(mdev->cpu_mask))
1536 ord = mdev_to_minor(mdev) % cpumask_weight(cpu_online_mask);
1537 for_each_online_cpu(cpu) {
1539 cpumask_set_cpu(cpu, mdev->cpu_mask);
1543 /* should not be reached */
1544 cpumask_setall(mdev->cpu_mask);
1548 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
1549 * @mdev: DRBD device.
1551 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
1554 void drbd_thread_current_set_cpu(struct drbd_conf *mdev)
1556 struct task_struct *p = current;
1557 struct drbd_thread *thi =
1558 p == mdev->asender.task ? &mdev->asender :
1559 p == mdev->receiver.task ? &mdev->receiver :
1560 p == mdev->worker.task ? &mdev->worker :
1564 if (!thi->reset_cpu_mask)
1566 thi->reset_cpu_mask = 0;
1567 set_cpus_allowed_ptr(p, mdev->cpu_mask);
1571 /* the appropriate socket mutex must be held already */
1572 int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1573 enum drbd_packets cmd, struct p_header *h,
1574 size_t size, unsigned msg_flags)
1578 ERR_IF(!h) return FALSE;
1579 ERR_IF(!size) return FALSE;
1581 h->magic = BE_DRBD_MAGIC;
1582 h->command = cpu_to_be16(cmd);
1583 h->length = cpu_to_be16(size-sizeof(struct p_header));
1585 sent = drbd_send(mdev, sock, h, size, msg_flags);
1587 ok = (sent == size);
1589 dev_err(DEV, "short sent %s size=%d sent=%d\n",
1590 cmdname(cmd), (int)size, sent);
1594 /* don't pass the socket. we may only look at it
1595 * when we hold the appropriate socket mutex.
1597 int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1598 enum drbd_packets cmd, struct p_header *h, size_t size)
1601 struct socket *sock;
1603 if (use_data_socket) {
1604 mutex_lock(&mdev->data.mutex);
1605 sock = mdev->data.socket;
1607 mutex_lock(&mdev->meta.mutex);
1608 sock = mdev->meta.socket;
1611 /* drbd_disconnect() could have called drbd_free_sock()
1612 * while we were waiting in down()... */
1613 if (likely(sock != NULL))
1614 ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0);
1616 if (use_data_socket)
1617 mutex_unlock(&mdev->data.mutex);
1619 mutex_unlock(&mdev->meta.mutex);
1623 int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
1629 h.magic = BE_DRBD_MAGIC;
1630 h.command = cpu_to_be16(cmd);
1631 h.length = cpu_to_be16(size);
1633 if (!drbd_get_data_sock(mdev))
1637 drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0));
1639 drbd_send(mdev, mdev->data.socket, data, size, 0));
1641 drbd_put_data_sock(mdev);
1646 int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc)
1648 struct p_rs_param_89 *p;
1649 struct socket *sock;
1651 const int apv = mdev->agreed_pro_version;
1653 size = apv <= 87 ? sizeof(struct p_rs_param)
1654 : apv == 88 ? sizeof(struct p_rs_param)
1655 + strlen(mdev->sync_conf.verify_alg) + 1
1656 : /* 89 */ sizeof(struct p_rs_param_89);
1658 /* used from admin command context and receiver/worker context.
1659 * to avoid kmalloc, grab the socket right here,
1660 * then use the pre-allocated sbuf there */
1661 mutex_lock(&mdev->data.mutex);
1662 sock = mdev->data.socket;
1664 if (likely(sock != NULL)) {
1665 enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
1667 p = &mdev->data.sbuf.rs_param_89;
1669 /* initialize verify_alg and csums_alg */
1670 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
1672 p->rate = cpu_to_be32(sc->rate);
1675 strcpy(p->verify_alg, mdev->sync_conf.verify_alg);
1677 strcpy(p->csums_alg, mdev->sync_conf.csums_alg);
1679 rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
1681 rv = 0; /* not ok */
1683 mutex_unlock(&mdev->data.mutex);
1688 int drbd_send_protocol(struct drbd_conf *mdev)
1690 struct p_protocol *p;
1693 size = sizeof(struct p_protocol);
1695 if (mdev->agreed_pro_version >= 87)
1696 size += strlen(mdev->net_conf->integrity_alg) + 1;
1698 /* we must not recurse into our own queue,
1699 * as that is blocked during handshake */
1700 p = kmalloc(size, GFP_NOIO);
1704 p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol);
1705 p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p);
1706 p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p);
1707 p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p);
1708 p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries);
1711 if (mdev->net_conf->want_lose)
1713 if (mdev->net_conf->dry_run) {
1714 if (mdev->agreed_pro_version >= 92)
1717 dev_err(DEV, "--dry-run is not supported by peer");
1722 p->conn_flags = cpu_to_be32(cf);
1724 if (mdev->agreed_pro_version >= 87)
1725 strcpy(p->integrity_alg, mdev->net_conf->integrity_alg);
1727 rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL,
1728 (struct p_header *)p, size);
1733 int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
1738 if (!get_ldev_if_state(mdev, D_NEGOTIATING))
1741 for (i = UI_CURRENT; i < UI_SIZE; i++)
1742 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
1744 mdev->comm_bm_set = drbd_bm_total_weight(mdev);
1745 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
1746 uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
1747 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
1748 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
1749 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
1753 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS,
1754 (struct p_header *)&p, sizeof(p));
1757 int drbd_send_uuids(struct drbd_conf *mdev)
1759 return _drbd_send_uuids(mdev, 0);
1762 int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
1764 return _drbd_send_uuids(mdev, 8);
1768 int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val)
1772 p.uuid = cpu_to_be64(val);
1774 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID,
1775 (struct p_header *)&p, sizeof(p));
1778 int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags)
1781 sector_t d_size, u_size;
1785 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
1786 D_ASSERT(mdev->ldev->backing_bdev);
1787 d_size = drbd_get_max_capacity(mdev->ldev);
1788 u_size = mdev->ldev->dc.disk_size;
1789 q_order_type = drbd_queue_order_type(mdev);
1794 q_order_type = QUEUE_ORDERED_NONE;
1797 p.d_size = cpu_to_be64(d_size);
1798 p.u_size = cpu_to_be64(u_size);
1799 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
1800 p.max_segment_size = cpu_to_be32(queue_max_segment_size(mdev->rq_queue));
1801 p.queue_order_type = cpu_to_be16(q_order_type);
1802 p.dds_flags = cpu_to_be16(flags);
1804 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES,
1805 (struct p_header *)&p, sizeof(p));
1810 * drbd_send_state() - Sends the drbd state to the peer
1811 * @mdev: DRBD device.
1813 int drbd_send_state(struct drbd_conf *mdev)
1815 struct socket *sock;
1819 /* Grab state lock so we wont send state if we're in the middle
1820 * of a cluster wide state change on another thread */
1821 drbd_state_lock(mdev);
1823 mutex_lock(&mdev->data.mutex);
1825 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
1826 sock = mdev->data.socket;
1828 if (likely(sock != NULL)) {
1829 ok = _drbd_send_cmd(mdev, sock, P_STATE,
1830 (struct p_header *)&p, sizeof(p), 0);
1833 mutex_unlock(&mdev->data.mutex);
1835 drbd_state_unlock(mdev);
1839 int drbd_send_state_req(struct drbd_conf *mdev,
1840 union drbd_state mask, union drbd_state val)
1842 struct p_req_state p;
1844 p.mask = cpu_to_be32(mask.i);
1845 p.val = cpu_to_be32(val.i);
1847 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ,
1848 (struct p_header *)&p, sizeof(p));
1851 int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode)
1853 struct p_req_state_reply p;
1855 p.retcode = cpu_to_be32(retcode);
1857 return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY,
1858 (struct p_header *)&p, sizeof(p));
1861 int fill_bitmap_rle_bits(struct drbd_conf *mdev,
1862 struct p_compressed_bm *p,
1863 struct bm_xfer_ctx *c)
1865 struct bitstream bs;
1866 unsigned long plain_bits;
1873 /* may we use this feature? */
1874 if ((mdev->sync_conf.use_rle == 0) ||
1875 (mdev->agreed_pro_version < 90))
1878 if (c->bit_offset >= c->bm_bits)
1879 return 0; /* nothing to do. */
1881 /* use at most thus many bytes */
1882 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
1883 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
1884 /* plain bits covered in this code string */
1887 /* p->encoding & 0x80 stores whether the first run length is set.
1888 * bit offset is implicit.
1889 * start with toggle == 2 to be able to tell the first iteration */
1892 /* see how much plain bits we can stuff into one packet
1893 * using RLE and VLI. */
1895 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
1896 : _drbd_bm_find_next(mdev, c->bit_offset);
1899 rl = tmp - c->bit_offset;
1901 if (toggle == 2) { /* first iteration */
1903 /* the first checked bit was set,
1904 * store start value, */
1905 DCBP_set_start(p, 1);
1906 /* but skip encoding of zero run length */
1910 DCBP_set_start(p, 0);
1913 /* paranoia: catch zero runlength.
1914 * can only happen if bitmap is modified while we scan it. */
1916 dev_err(DEV, "unexpected zero runlength while encoding bitmap "
1917 "t:%u bo:%lu\n", toggle, c->bit_offset);
1921 bits = vli_encode_bits(&bs, rl);
1922 if (bits == -ENOBUFS) /* buffer full */
1925 dev_err(DEV, "error while encoding bitmap: %d\n", bits);
1931 c->bit_offset = tmp;
1932 } while (c->bit_offset < c->bm_bits);
1934 len = bs.cur.b - p->code + !!bs.cur.bit;
1936 if (plain_bits < (len << 3)) {
1937 /* incompressible with this method.
1938 * we need to rewind both word and bit position. */
1939 c->bit_offset -= plain_bits;
1940 bm_xfer_ctx_bit_to_word_offset(c);
1941 c->bit_offset = c->word_offset * BITS_PER_LONG;
1945 /* RLE + VLI was able to compress it just fine.
1946 * update c->word_offset. */
1947 bm_xfer_ctx_bit_to_word_offset(c);
1949 /* store pad_bits */
1950 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
1955 enum { OK, FAILED, DONE }
1956 send_bitmap_rle_or_plain(struct drbd_conf *mdev,
1957 struct p_header *h, struct bm_xfer_ctx *c)
1959 struct p_compressed_bm *p = (void*)h;
1960 unsigned long num_words;
1964 len = fill_bitmap_rle_bits(mdev, p, c);
1970 DCBP_set_code(p, RLE_VLI_Bits);
1971 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h,
1972 sizeof(*p) + len, 0);
1975 c->bytes[0] += sizeof(*p) + len;
1977 if (c->bit_offset >= c->bm_bits)
1980 /* was not compressible.
1981 * send a buffer full of plain text bits instead. */
1982 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
1983 len = num_words * sizeof(long);
1985 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
1986 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP,
1987 h, sizeof(struct p_header) + len, 0);
1988 c->word_offset += num_words;
1989 c->bit_offset = c->word_offset * BITS_PER_LONG;
1992 c->bytes[1] += sizeof(struct p_header) + len;
1994 if (c->bit_offset > c->bm_bits)
1995 c->bit_offset = c->bm_bits;
1997 ok = ok ? ((len == 0) ? DONE : OK) : FAILED;
2000 INFO_bm_xfer_stats(mdev, "send", c);
2004 /* See the comment at receive_bitmap() */
2005 int _drbd_send_bitmap(struct drbd_conf *mdev)
2007 struct bm_xfer_ctx c;
2011 ERR_IF(!mdev->bitmap) return FALSE;
2013 /* maybe we should use some per thread scratch page,
2014 * and allocate that during initial device creation? */
2015 p = (struct p_header *) __get_free_page(GFP_NOIO);
2017 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
2021 if (get_ldev(mdev)) {
2022 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
2023 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
2024 drbd_bm_set_all(mdev);
2025 if (drbd_bm_write(mdev)) {
2026 /* write_bm did fail! Leave full sync flag set in Meta P_DATA
2027 * but otherwise process as per normal - need to tell other
2028 * side that a full resync is required! */
2029 dev_err(DEV, "Failed to write bitmap to disk!\n");
2031 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2038 c = (struct bm_xfer_ctx) {
2039 .bm_bits = drbd_bm_bits(mdev),
2040 .bm_words = drbd_bm_words(mdev),
2044 ret = send_bitmap_rle_or_plain(mdev, p, &c);
2045 } while (ret == OK);
2047 free_page((unsigned long) p);
2048 return (ret == DONE);
2051 int drbd_send_bitmap(struct drbd_conf *mdev)
2055 if (!drbd_get_data_sock(mdev))
2057 err = !_drbd_send_bitmap(mdev);
2058 drbd_put_data_sock(mdev);
2062 int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
2065 struct p_barrier_ack p;
2067 p.barrier = barrier_nr;
2068 p.set_size = cpu_to_be32(set_size);
2070 if (mdev->state.conn < C_CONNECTED)
2072 ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK,
2073 (struct p_header *)&p, sizeof(p));
2078 * _drbd_send_ack() - Sends an ack packet
2079 * @mdev: DRBD device.
2080 * @cmd: Packet command code.
2081 * @sector: sector, needs to be in big endian byte order
2082 * @blksize: size in byte, needs to be in big endian byte order
2083 * @block_id: Id, big endian byte order
2085 static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
2091 struct p_block_ack p;
2094 p.block_id = block_id;
2095 p.blksize = blksize;
2096 p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq));
2098 if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED)
2100 ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd,
2101 (struct p_header *)&p, sizeof(p));
2105 int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
2108 const int header_size = sizeof(struct p_data)
2109 - sizeof(struct p_header);
2110 int data_size = ((struct p_header *)dp)->length - header_size;
2112 return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
2116 int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
2117 struct p_block_req *rp)
2119 return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
2123 * drbd_send_ack() - Sends an ack packet
2124 * @mdev: DRBD device.
2125 * @cmd: Packet command code.
2128 int drbd_send_ack(struct drbd_conf *mdev,
2129 enum drbd_packets cmd, struct drbd_epoch_entry *e)
2131 return _drbd_send_ack(mdev, cmd,
2132 cpu_to_be64(e->sector),
2133 cpu_to_be32(e->size),
2137 /* This function misuses the block_id field to signal if the blocks
2138 * are is sync or not. */
2139 int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
2140 sector_t sector, int blksize, u64 block_id)
2142 return _drbd_send_ack(mdev, cmd,
2143 cpu_to_be64(sector),
2144 cpu_to_be32(blksize),
2145 cpu_to_be64(block_id));
2148 int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
2149 sector_t sector, int size, u64 block_id)
2152 struct p_block_req p;
2154 p.sector = cpu_to_be64(sector);
2155 p.block_id = block_id;
2156 p.blksize = cpu_to_be32(size);
2158 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd,
2159 (struct p_header *)&p, sizeof(p));
2163 int drbd_send_drequest_csum(struct drbd_conf *mdev,
2164 sector_t sector, int size,
2165 void *digest, int digest_size,
2166 enum drbd_packets cmd)
2169 struct p_block_req p;
2171 p.sector = cpu_to_be64(sector);
2172 p.block_id = BE_DRBD_MAGIC + 0xbeef;
2173 p.blksize = cpu_to_be32(size);
2175 p.head.magic = BE_DRBD_MAGIC;
2176 p.head.command = cpu_to_be16(cmd);
2177 p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header) + digest_size);
2179 mutex_lock(&mdev->data.mutex);
2181 ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0));
2182 ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0));
2184 mutex_unlock(&mdev->data.mutex);
2189 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
2192 struct p_block_req p;
2194 p.sector = cpu_to_be64(sector);
2195 p.block_id = BE_DRBD_MAGIC + 0xbabe;
2196 p.blksize = cpu_to_be32(size);
2198 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST,
2199 (struct p_header *)&p, sizeof(p));
2203 static int drbd_send_delay_probe(struct drbd_conf *mdev, struct drbd_socket *ds)
2205 struct p_delay_probe dp;
2209 mutex_lock(&ds->mutex);
2210 if (likely(ds->socket)) {
2211 do_gettimeofday(&now);
2212 offset = now.tv_usec - mdev->dps_time.tv_usec +
2213 (now.tv_sec - mdev->dps_time.tv_sec) * 1000000;
2214 dp.seq_num = cpu_to_be32(mdev->delay_seq);
2215 dp.offset = cpu_to_be32(offset);
2217 ok = _drbd_send_cmd(mdev, ds->socket, P_DELAY_PROBE,
2218 (struct p_header *)&dp, sizeof(dp), 0);
2220 mutex_unlock(&ds->mutex);
2225 static int drbd_send_delay_probes(struct drbd_conf *mdev)
2230 do_gettimeofday(&mdev->dps_time);
2231 ok = drbd_send_delay_probe(mdev, &mdev->meta);
2232 ok = ok && drbd_send_delay_probe(mdev, &mdev->data);
2234 mdev->dp_volume_last = mdev->send_cnt;
2235 mod_timer(&mdev->delay_probe_timer, jiffies + mdev->sync_conf.dp_interval * HZ / 10);
2240 /* called on sndtimeo
2241 * returns FALSE if we should retry,
2242 * TRUE if we think connection is dead
2244 static int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock)
2247 /* long elapsed = (long)(jiffies - mdev->last_received); */
2249 drop_it = mdev->meta.socket == sock
2250 || !mdev->asender.task
2251 || get_t_state(&mdev->asender) != Running
2252 || mdev->state.conn < C_CONNECTED;
2257 drop_it = !--mdev->ko_count;
2259 dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
2260 current->comm, current->pid, mdev->ko_count);
2264 return drop_it; /* && (mdev->state == R_PRIMARY) */;
2267 /* The idea of sendpage seems to be to put some kind of reference
2268 * to the page into the skb, and to hand it over to the NIC. In
2269 * this process get_page() gets called.
2271 * As soon as the page was really sent over the network put_page()
2272 * gets called by some part of the network layer. [ NIC driver? ]
2274 * [ get_page() / put_page() increment/decrement the count. If count
2275 * reaches 0 the page will be freed. ]
2277 * This works nicely with pages from FSs.
2278 * But this means that in protocol A we might signal IO completion too early!
2280 * In order not to corrupt data during a resync we must make sure
2281 * that we do not reuse our own buffer pages (EEs) to early, therefore
2282 * we have the net_ee list.
2284 * XFS seems to have problems, still, it submits pages with page_count == 0!
2285 * As a workaround, we disable sendpage on pages
2286 * with page_count == 0 or PageSlab.
2288 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
2289 int offset, size_t size)
2291 int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, 0);
2294 mdev->send_cnt += size>>9;
2295 return sent == size;
2298 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
2299 int offset, size_t size)
2301 mm_segment_t oldfs = get_fs();
2305 /* e.g. XFS meta- & log-data is in slab pages, which have a
2306 * page_count of 0 and/or have PageSlab() set.
2307 * we cannot use send_page for those, as that does get_page();
2308 * put_page(); and would cause either a VM_BUG directly, or
2309 * __page_cache_release a page that would actually still be referenced
2310 * by someone, leading to some obscure delayed Oops somewhere else. */
2311 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
2312 return _drbd_no_send_page(mdev, page, offset, size);
2314 drbd_update_congested(mdev);
2317 sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page,
2320 if (sent == -EAGAIN) {
2321 if (we_should_drop_the_connection(mdev,
2328 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
2329 __func__, (int)size, len, sent);
2334 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
2336 clear_bit(NET_CONGESTED, &mdev->flags);
2340 mdev->send_cnt += size>>9;
2344 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
2346 struct bio_vec *bvec;
2348 __bio_for_each_segment(bvec, bio, i, 0) {
2349 if (!_drbd_no_send_page(mdev, bvec->bv_page,
2350 bvec->bv_offset, bvec->bv_len))
2356 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
2358 struct bio_vec *bvec;
2360 __bio_for_each_segment(bvec, bio, i, 0) {
2361 if (!_drbd_send_page(mdev, bvec->bv_page,
2362 bvec->bv_offset, bvec->bv_len))
2369 static int _drbd_send_zc_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e)
2371 struct page *page = e->pages;
2372 unsigned len = e->size;
2373 page_chain_for_each(page) {
2374 unsigned l = min_t(unsigned, len, PAGE_SIZE);
2375 if (!_drbd_send_page(mdev, page, 0, l))
2382 static void consider_delay_probes(struct drbd_conf *mdev)
2384 if (mdev->state.conn != C_SYNC_SOURCE || mdev->agreed_pro_version < 93)
2387 if (mdev->dp_volume_last + mdev->sync_conf.dp_volume * 2 < mdev->send_cnt)
2388 drbd_send_delay_probes(mdev);
2391 static int w_delay_probes(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
2393 if (!cancel && mdev->state.conn == C_SYNC_SOURCE)
2394 drbd_send_delay_probes(mdev);
2399 static void delay_probe_timer_fn(unsigned long data)
2401 struct drbd_conf *mdev = (struct drbd_conf *) data;
2403 if (list_empty(&mdev->delay_probe_work.list))
2404 drbd_queue_work(&mdev->data.work, &mdev->delay_probe_work);
2407 /* Used to send write requests
2408 * R_PRIMARY -> Peer (P_DATA)
2410 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
2414 unsigned int dp_flags = 0;
2418 if (!drbd_get_data_sock(mdev))
2421 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2422 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2424 p.head.magic = BE_DRBD_MAGIC;
2425 p.head.command = cpu_to_be16(P_DATA);
2427 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + req->size);
2429 p.sector = cpu_to_be64(req->sector);
2430 p.block_id = (unsigned long)req;
2431 p.seq_num = cpu_to_be32(req->seq_num =
2432 atomic_add_return(1, &mdev->packet_seq));
2435 /* NOTE: no need to check if barriers supported here as we would
2436 * not pass the test in make_request_common in that case
2438 if (bio_rw_flagged(req->master_bio, BIO_RW_BARRIER)) {
2439 dev_err(DEV, "ASSERT FAILED would have set DP_HARDBARRIER\n");
2440 /* dp_flags |= DP_HARDBARRIER; */
2442 if (bio_rw_flagged(req->master_bio, BIO_RW_SYNCIO))
2443 dp_flags |= DP_RW_SYNC;
2444 /* for now handle SYNCIO and UNPLUG
2445 * as if they still were one and the same flag */
2446 if (bio_rw_flagged(req->master_bio, BIO_RW_UNPLUG))
2447 dp_flags |= DP_RW_SYNC;
2448 if (mdev->state.conn >= C_SYNC_SOURCE &&
2449 mdev->state.conn <= C_PAUSED_SYNC_T)
2450 dp_flags |= DP_MAY_SET_IN_SYNC;
2452 p.dp_flags = cpu_to_be32(dp_flags);
2453 set_bit(UNPLUG_REMOTE, &mdev->flags);
2455 drbd_send(mdev, mdev->data.socket, &p, sizeof(p), MSG_MORE));
2457 dgb = mdev->int_dig_out;
2458 drbd_csum_bio(mdev, mdev->integrity_w_tfm, req->master_bio, dgb);
2459 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2462 if (mdev->net_conf->wire_protocol == DRBD_PROT_A)
2463 ok = _drbd_send_bio(mdev, req->master_bio);
2465 ok = _drbd_send_zc_bio(mdev, req->master_bio);
2468 drbd_put_data_sock(mdev);
2471 consider_delay_probes(mdev);
2476 /* answer packet, used to send data back for read requests:
2477 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
2478 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
2480 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
2481 struct drbd_epoch_entry *e)
2488 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2489 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2491 p.head.magic = BE_DRBD_MAGIC;
2492 p.head.command = cpu_to_be16(cmd);
2494 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + e->size);
2496 p.sector = cpu_to_be64(e->sector);
2497 p.block_id = e->block_id;
2498 /* p.seq_num = 0; No sequence numbers here.. */
2500 /* Only called by our kernel thread.
2501 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
2502 * in response to admin command or module unload.
2504 if (!drbd_get_data_sock(mdev))
2507 ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p,
2508 sizeof(p), MSG_MORE);
2510 dgb = mdev->int_dig_out;
2511 drbd_csum_ee(mdev, mdev->integrity_w_tfm, e, dgb);
2512 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2515 ok = _drbd_send_zc_ee(mdev, e);
2517 drbd_put_data_sock(mdev);
2520 consider_delay_probes(mdev);
2526 drbd_send distinguishes two cases:
2528 Packets sent via the data socket "sock"
2529 and packets sent via the meta data socket "msock"
2532 -----------------+-------------------------+------------------------------
2533 timeout conf.timeout / 2 conf.timeout / 2
2534 timeout action send a ping via msock Abort communication
2535 and close all sockets
2539 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
2541 int drbd_send(struct drbd_conf *mdev, struct socket *sock,
2542 void *buf, size_t size, unsigned msg_flags)
2551 /* THINK if (signal_pending) return ... ? */
2556 msg.msg_name = NULL;
2557 msg.msg_namelen = 0;
2558 msg.msg_control = NULL;
2559 msg.msg_controllen = 0;
2560 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
2562 if (sock == mdev->data.socket) {
2563 mdev->ko_count = mdev->net_conf->ko_count;
2564 drbd_update_congested(mdev);
2568 * tcp_sendmsg does _not_ use its size parameter at all ?
2570 * -EAGAIN on timeout, -EINTR on signal.
2573 * do we need to block DRBD_SIG if sock == &meta.socket ??
2574 * otherwise wake_asender() might interrupt some send_*Ack !
2576 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
2577 if (rv == -EAGAIN) {
2578 if (we_should_drop_the_connection(mdev, sock))
2585 flush_signals(current);
2593 } while (sent < size);
2595 if (sock == mdev->data.socket)
2596 clear_bit(NET_CONGESTED, &mdev->flags);
2599 if (rv != -EAGAIN) {
2600 dev_err(DEV, "%s_sendmsg returned %d\n",
2601 sock == mdev->meta.socket ? "msock" : "sock",
2603 drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE));
2605 drbd_force_state(mdev, NS(conn, C_TIMEOUT));
2611 static int drbd_open(struct block_device *bdev, fmode_t mode)
2613 struct drbd_conf *mdev = bdev->bd_disk->private_data;
2614 unsigned long flags;
2617 spin_lock_irqsave(&mdev->req_lock, flags);
2618 /* to have a stable mdev->state.role
2619 * and no race with updating open_cnt */
2621 if (mdev->state.role != R_PRIMARY) {
2622 if (mode & FMODE_WRITE)
2624 else if (!allow_oos)
2630 spin_unlock_irqrestore(&mdev->req_lock, flags);
2635 static int drbd_release(struct gendisk *gd, fmode_t mode)
2637 struct drbd_conf *mdev = gd->private_data;
2642 static void drbd_unplug_fn(struct request_queue *q)
2644 struct drbd_conf *mdev = q->queuedata;
2647 spin_lock_irq(q->queue_lock);
2649 spin_unlock_irq(q->queue_lock);
2651 /* only if connected */
2652 spin_lock_irq(&mdev->req_lock);
2653 if (mdev->state.pdsk >= D_INCONSISTENT && mdev->state.conn >= C_CONNECTED) {
2654 D_ASSERT(mdev->state.role == R_PRIMARY);
2655 if (test_and_clear_bit(UNPLUG_REMOTE, &mdev->flags)) {
2656 /* add to the data.work queue,
2657 * unless already queued.
2658 * XXX this might be a good addition to drbd_queue_work
2659 * anyways, to detect "double queuing" ... */
2660 if (list_empty(&mdev->unplug_work.list))
2661 drbd_queue_work(&mdev->data.work,
2662 &mdev->unplug_work);
2665 spin_unlock_irq(&mdev->req_lock);
2667 if (mdev->state.disk >= D_INCONSISTENT)
2671 static void drbd_set_defaults(struct drbd_conf *mdev)
2673 mdev->sync_conf.after = DRBD_AFTER_DEF;
2674 mdev->sync_conf.rate = DRBD_RATE_DEF;
2675 mdev->sync_conf.al_extents = DRBD_AL_EXTENTS_DEF;
2676 mdev->state = (union drbd_state) {
2677 { .role = R_SECONDARY,
2679 .conn = C_STANDALONE,
2686 void drbd_init_set_defaults(struct drbd_conf *mdev)
2688 /* the memset(,0,) did most of this.
2689 * note: only assignments, no allocation in here */
2691 drbd_set_defaults(mdev);
2693 /* for now, we do NOT yet support it,
2694 * even though we start some framework
2695 * to eventually support barriers */
2696 set_bit(NO_BARRIER_SUPP, &mdev->flags);
2698 atomic_set(&mdev->ap_bio_cnt, 0);
2699 atomic_set(&mdev->ap_pending_cnt, 0);
2700 atomic_set(&mdev->rs_pending_cnt, 0);
2701 atomic_set(&mdev->unacked_cnt, 0);
2702 atomic_set(&mdev->local_cnt, 0);
2703 atomic_set(&mdev->net_cnt, 0);
2704 atomic_set(&mdev->packet_seq, 0);
2705 atomic_set(&mdev->pp_in_use, 0);
2706 atomic_set(&mdev->new_c_uuid, 0);
2708 mutex_init(&mdev->md_io_mutex);
2709 mutex_init(&mdev->data.mutex);
2710 mutex_init(&mdev->meta.mutex);
2711 sema_init(&mdev->data.work.s, 0);
2712 sema_init(&mdev->meta.work.s, 0);
2713 mutex_init(&mdev->state_mutex);
2715 spin_lock_init(&mdev->data.work.q_lock);
2716 spin_lock_init(&mdev->meta.work.q_lock);
2718 spin_lock_init(&mdev->al_lock);
2719 spin_lock_init(&mdev->req_lock);
2720 spin_lock_init(&mdev->peer_seq_lock);
2721 spin_lock_init(&mdev->epoch_lock);
2723 INIT_LIST_HEAD(&mdev->active_ee);
2724 INIT_LIST_HEAD(&mdev->sync_ee);
2725 INIT_LIST_HEAD(&mdev->done_ee);
2726 INIT_LIST_HEAD(&mdev->read_ee);
2727 INIT_LIST_HEAD(&mdev->net_ee);
2728 INIT_LIST_HEAD(&mdev->resync_reads);
2729 INIT_LIST_HEAD(&mdev->data.work.q);
2730 INIT_LIST_HEAD(&mdev->meta.work.q);
2731 INIT_LIST_HEAD(&mdev->resync_work.list);
2732 INIT_LIST_HEAD(&mdev->unplug_work.list);
2733 INIT_LIST_HEAD(&mdev->md_sync_work.list);
2734 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
2735 INIT_LIST_HEAD(&mdev->delay_probes);
2736 INIT_LIST_HEAD(&mdev->delay_probe_work.list);
2737 INIT_LIST_HEAD(&mdev->uuid_work.list);
2739 mdev->resync_work.cb = w_resync_inactive;
2740 mdev->unplug_work.cb = w_send_write_hint;
2741 mdev->md_sync_work.cb = w_md_sync;
2742 mdev->bm_io_work.w.cb = w_bitmap_io;
2743 mdev->delay_probe_work.cb = w_delay_probes;
2744 mdev->uuid_work.cb = w_new_current_uuid;
2745 init_timer(&mdev->resync_timer);
2746 init_timer(&mdev->md_sync_timer);
2747 init_timer(&mdev->delay_probe_timer);
2748 mdev->resync_timer.function = resync_timer_fn;
2749 mdev->resync_timer.data = (unsigned long) mdev;
2750 mdev->md_sync_timer.function = md_sync_timer_fn;
2751 mdev->md_sync_timer.data = (unsigned long) mdev;
2752 mdev->delay_probe_timer.function = delay_probe_timer_fn;
2753 mdev->delay_probe_timer.data = (unsigned long) mdev;
2756 init_waitqueue_head(&mdev->misc_wait);
2757 init_waitqueue_head(&mdev->state_wait);
2758 init_waitqueue_head(&mdev->ee_wait);
2759 init_waitqueue_head(&mdev->al_wait);
2760 init_waitqueue_head(&mdev->seq_wait);
2762 drbd_thread_init(mdev, &mdev->receiver, drbdd_init);
2763 drbd_thread_init(mdev, &mdev->worker, drbd_worker);
2764 drbd_thread_init(mdev, &mdev->asender, drbd_asender);
2766 mdev->agreed_pro_version = PRO_VERSION_MAX;
2767 mdev->write_ordering = WO_bio_barrier;
2768 mdev->resync_wenr = LC_FREE;
2771 void drbd_mdev_cleanup(struct drbd_conf *mdev)
2773 if (mdev->receiver.t_state != None)
2774 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
2775 mdev->receiver.t_state);
2777 /* no need to lock it, I'm the only thread alive */
2778 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
2779 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
2790 mdev->rs_mark_left =
2791 mdev->rs_mark_time = 0;
2792 D_ASSERT(mdev->net_conf == NULL);
2794 drbd_set_my_capacity(mdev, 0);
2796 /* maybe never allocated. */
2797 drbd_bm_resize(mdev, 0, 1);
2798 drbd_bm_cleanup(mdev);
2801 drbd_free_resources(mdev);
2804 * currently we drbd_init_ee only on module load, so
2805 * we may do drbd_release_ee only on module unload!
2807 D_ASSERT(list_empty(&mdev->active_ee));
2808 D_ASSERT(list_empty(&mdev->sync_ee));
2809 D_ASSERT(list_empty(&mdev->done_ee));
2810 D_ASSERT(list_empty(&mdev->read_ee));
2811 D_ASSERT(list_empty(&mdev->net_ee));
2812 D_ASSERT(list_empty(&mdev->resync_reads));
2813 D_ASSERT(list_empty(&mdev->data.work.q));
2814 D_ASSERT(list_empty(&mdev->meta.work.q));
2815 D_ASSERT(list_empty(&mdev->resync_work.list));
2816 D_ASSERT(list_empty(&mdev->unplug_work.list));
2821 static void drbd_destroy_mempools(void)
2825 while (drbd_pp_pool) {
2826 page = drbd_pp_pool;
2827 drbd_pp_pool = (struct page *)page_private(page);
2832 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
2834 if (drbd_ee_mempool)
2835 mempool_destroy(drbd_ee_mempool);
2836 if (drbd_request_mempool)
2837 mempool_destroy(drbd_request_mempool);
2839 kmem_cache_destroy(drbd_ee_cache);
2840 if (drbd_request_cache)
2841 kmem_cache_destroy(drbd_request_cache);
2842 if (drbd_bm_ext_cache)
2843 kmem_cache_destroy(drbd_bm_ext_cache);
2844 if (drbd_al_ext_cache)
2845 kmem_cache_destroy(drbd_al_ext_cache);
2847 drbd_ee_mempool = NULL;
2848 drbd_request_mempool = NULL;
2849 drbd_ee_cache = NULL;
2850 drbd_request_cache = NULL;
2851 drbd_bm_ext_cache = NULL;
2852 drbd_al_ext_cache = NULL;
2857 static int drbd_create_mempools(void)
2860 const int number = (DRBD_MAX_SEGMENT_SIZE/PAGE_SIZE) * minor_count;
2863 /* prepare our caches and mempools */
2864 drbd_request_mempool = NULL;
2865 drbd_ee_cache = NULL;
2866 drbd_request_cache = NULL;
2867 drbd_bm_ext_cache = NULL;
2868 drbd_al_ext_cache = NULL;
2869 drbd_pp_pool = NULL;
2872 drbd_request_cache = kmem_cache_create(
2873 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
2874 if (drbd_request_cache == NULL)
2877 drbd_ee_cache = kmem_cache_create(
2878 "drbd_ee", sizeof(struct drbd_epoch_entry), 0, 0, NULL);
2879 if (drbd_ee_cache == NULL)
2882 drbd_bm_ext_cache = kmem_cache_create(
2883 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
2884 if (drbd_bm_ext_cache == NULL)
2887 drbd_al_ext_cache = kmem_cache_create(
2888 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
2889 if (drbd_al_ext_cache == NULL)
2893 drbd_request_mempool = mempool_create(number,
2894 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
2895 if (drbd_request_mempool == NULL)
2898 drbd_ee_mempool = mempool_create(number,
2899 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2900 if (drbd_request_mempool == NULL)
2903 /* drbd's page pool */
2904 spin_lock_init(&drbd_pp_lock);
2906 for (i = 0; i < number; i++) {
2907 page = alloc_page(GFP_HIGHUSER);
2910 set_page_private(page, (unsigned long)drbd_pp_pool);
2911 drbd_pp_pool = page;
2913 drbd_pp_vacant = number;
2918 drbd_destroy_mempools(); /* in case we allocated some */
2922 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
2925 /* just so we have it. you never know what interesting things we
2926 * might want to do here some day...
2932 static struct notifier_block drbd_notifier = {
2933 .notifier_call = drbd_notify_sys,
2936 static void drbd_release_ee_lists(struct drbd_conf *mdev)
2940 rr = drbd_release_ee(mdev, &mdev->active_ee);
2942 dev_err(DEV, "%d EEs in active list found!\n", rr);
2944 rr = drbd_release_ee(mdev, &mdev->sync_ee);
2946 dev_err(DEV, "%d EEs in sync list found!\n", rr);
2948 rr = drbd_release_ee(mdev, &mdev->read_ee);
2950 dev_err(DEV, "%d EEs in read list found!\n", rr);
2952 rr = drbd_release_ee(mdev, &mdev->done_ee);
2954 dev_err(DEV, "%d EEs in done list found!\n", rr);
2956 rr = drbd_release_ee(mdev, &mdev->net_ee);
2958 dev_err(DEV, "%d EEs in net list found!\n", rr);
2961 /* caution. no locking.
2962 * currently only used from module cleanup code. */
2963 static void drbd_delete_device(unsigned int minor)
2965 struct drbd_conf *mdev = minor_to_mdev(minor);
2970 /* paranoia asserts */
2971 if (mdev->open_cnt != 0)
2972 dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,
2973 __FILE__ , __LINE__);
2975 ERR_IF (!list_empty(&mdev->data.work.q)) {
2976 struct list_head *lp;
2977 list_for_each(lp, &mdev->data.work.q) {
2978 dev_err(DEV, "lp = %p\n", lp);
2981 /* end paranoia asserts */
2983 del_gendisk(mdev->vdisk);
2985 /* cleanup stuff that may have been allocated during
2986 * device (re-)configuration or state changes */
2988 if (mdev->this_bdev)
2989 bdput(mdev->this_bdev);
2991 drbd_free_resources(mdev);
2993 drbd_release_ee_lists(mdev);
2995 /* should be free'd on disconnect? */
2996 kfree(mdev->ee_hash);
2998 mdev->ee_hash_s = 0;
2999 mdev->ee_hash = NULL;
3002 lc_destroy(mdev->act_log);
3003 lc_destroy(mdev->resync);
3005 kfree(mdev->p_uuid);
3006 /* mdev->p_uuid = NULL; */
3008 kfree(mdev->int_dig_out);
3009 kfree(mdev->int_dig_in);
3010 kfree(mdev->int_dig_vv);
3012 /* cleanup the rest that has been
3013 * allocated from drbd_new_device
3014 * and actually free the mdev itself */
3015 drbd_free_mdev(mdev);
3018 static void drbd_cleanup(void)
3022 unregister_reboot_notifier(&drbd_notifier);
3028 remove_proc_entry("drbd", NULL);
3031 drbd_delete_device(i);
3032 drbd_destroy_mempools();
3037 unregister_blkdev(DRBD_MAJOR, "drbd");
3039 printk(KERN_INFO "drbd: module cleanup done.\n");
3043 * drbd_congested() - Callback for pdflush
3044 * @congested_data: User data
3045 * @bdi_bits: Bits pdflush is currently interested in
3047 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
3049 static int drbd_congested(void *congested_data, int bdi_bits)
3051 struct drbd_conf *mdev = congested_data;
3052 struct request_queue *q;
3056 if (!__inc_ap_bio_cond(mdev)) {
3057 /* DRBD has frozen IO */
3063 if (get_ldev(mdev)) {
3064 q = bdev_get_queue(mdev->ldev->backing_bdev);
3065 r = bdi_congested(&q->backing_dev_info, bdi_bits);
3071 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) {
3072 r |= (1 << BDI_async_congested);
3073 reason = reason == 'b' ? 'a' : 'n';
3077 mdev->congestion_reason = reason;
3081 struct drbd_conf *drbd_new_device(unsigned int minor)
3083 struct drbd_conf *mdev;
3084 struct gendisk *disk;
3085 struct request_queue *q;
3087 /* GFP_KERNEL, we are outside of all write-out paths */
3088 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
3091 if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL))
3092 goto out_no_cpumask;
3094 mdev->minor = minor;
3096 drbd_init_set_defaults(mdev);
3098 q = blk_alloc_queue(GFP_KERNEL);
3102 q->queuedata = mdev;
3104 disk = alloc_disk(1);
3109 set_disk_ro(disk, TRUE);
3112 disk->major = DRBD_MAJOR;
3113 disk->first_minor = minor;
3114 disk->fops = &drbd_ops;
3115 sprintf(disk->disk_name, "drbd%d", minor);
3116 disk->private_data = mdev;
3118 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
3119 /* we have no partitions. we contain only ourselves. */
3120 mdev->this_bdev->bd_contains = mdev->this_bdev;
3122 q->backing_dev_info.congested_fn = drbd_congested;
3123 q->backing_dev_info.congested_data = mdev;
3125 blk_queue_make_request(q, drbd_make_request_26);
3126 blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE);
3127 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
3128 blk_queue_merge_bvec(q, drbd_merge_bvec);
3129 q->queue_lock = &mdev->req_lock; /* needed since we use */
3130 /* plugging on a queue, that actually has no requests! */
3131 q->unplug_fn = drbd_unplug_fn;
3133 mdev->md_io_page = alloc_page(GFP_KERNEL);
3134 if (!mdev->md_io_page)
3135 goto out_no_io_page;
3137 if (drbd_bm_init(mdev))
3139 /* no need to lock access, we are still initializing this minor device. */
3143 mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL);
3144 if (!mdev->app_reads_hash)
3145 goto out_no_app_reads;
3147 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
3148 if (!mdev->current_epoch)
3151 INIT_LIST_HEAD(&mdev->current_epoch->list);
3156 /* out_whatever_else:
3157 kfree(mdev->current_epoch); */
3159 kfree(mdev->app_reads_hash);
3163 drbd_bm_cleanup(mdev);
3165 __free_page(mdev->md_io_page);
3169 blk_cleanup_queue(q);
3171 free_cpumask_var(mdev->cpu_mask);
3177 /* counterpart of drbd_new_device.
3178 * last part of drbd_delete_device. */
3179 void drbd_free_mdev(struct drbd_conf *mdev)
3181 kfree(mdev->current_epoch);
3182 kfree(mdev->app_reads_hash);
3184 if (mdev->bitmap) /* should no longer be there. */
3185 drbd_bm_cleanup(mdev);
3186 __free_page(mdev->md_io_page);
3187 put_disk(mdev->vdisk);
3188 blk_cleanup_queue(mdev->rq_queue);
3189 free_cpumask_var(mdev->cpu_mask);
3194 int __init drbd_init(void)
3198 if (sizeof(struct p_handshake) != 80) {
3200 "drbd: never change the size or layout "
3201 "of the HandShake packet.\n");
3205 if (1 > minor_count || minor_count > 255) {
3207 "drbd: invalid minor_count (%d)\n", minor_count);
3215 err = drbd_nl_init();
3219 err = register_blkdev(DRBD_MAJOR, "drbd");
3222 "drbd: unable to register block device major %d\n",
3227 register_reboot_notifier(&drbd_notifier);
3230 * allocate all necessary structs
3234 init_waitqueue_head(&drbd_pp_wait);
3236 drbd_proc = NULL; /* play safe for drbd_cleanup */
3237 minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
3242 err = drbd_create_mempools();
3246 drbd_proc = proc_create_data("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops, NULL);
3248 printk(KERN_ERR "drbd: unable to register proc file\n");
3252 rwlock_init(&global_state_lock);
3254 printk(KERN_INFO "drbd: initialized. "
3255 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
3256 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
3257 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
3258 printk(KERN_INFO "drbd: registered as block device major %d\n",
3260 printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
3262 return 0; /* Success! */
3267 /* currently always the case */
3268 printk(KERN_ERR "drbd: ran out of memory\n");
3270 printk(KERN_ERR "drbd: initialization failure\n");
3274 void drbd_free_bc(struct drbd_backing_dev *ldev)
3279 bd_release(ldev->backing_bdev);
3280 bd_release(ldev->md_bdev);
3282 fput(ldev->lo_file);
3283 fput(ldev->md_file);
3288 void drbd_free_sock(struct drbd_conf *mdev)
3290 if (mdev->data.socket) {
3291 mutex_lock(&mdev->data.mutex);
3292 kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR);
3293 sock_release(mdev->data.socket);
3294 mdev->data.socket = NULL;
3295 mutex_unlock(&mdev->data.mutex);
3297 if (mdev->meta.socket) {
3298 mutex_lock(&mdev->meta.mutex);
3299 kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR);
3300 sock_release(mdev->meta.socket);
3301 mdev->meta.socket = NULL;
3302 mutex_unlock(&mdev->meta.mutex);
3307 void drbd_free_resources(struct drbd_conf *mdev)
3309 crypto_free_hash(mdev->csums_tfm);
3310 mdev->csums_tfm = NULL;
3311 crypto_free_hash(mdev->verify_tfm);
3312 mdev->verify_tfm = NULL;
3313 crypto_free_hash(mdev->cram_hmac_tfm);
3314 mdev->cram_hmac_tfm = NULL;
3315 crypto_free_hash(mdev->integrity_w_tfm);
3316 mdev->integrity_w_tfm = NULL;
3317 crypto_free_hash(mdev->integrity_r_tfm);
3318 mdev->integrity_r_tfm = NULL;
3320 drbd_free_sock(mdev);
3323 drbd_free_bc(mdev->ldev);
3324 mdev->ldev = NULL;);
3327 /* meta data management */
3329 struct meta_data_on_disk {
3330 u64 la_size; /* last agreed size. */
3331 u64 uuid[UI_SIZE]; /* UUIDs. */
3334 u32 flags; /* MDF */
3337 u32 al_offset; /* offset to this block */
3338 u32 al_nr_extents; /* important for restoring the AL */
3339 /* `-- act_log->nr_elements <-- sync_conf.al_extents */
3340 u32 bm_offset; /* offset to the bitmap, from here */
3341 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
3342 u32 reserved_u32[4];
3347 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
3348 * @mdev: DRBD device.
3350 void drbd_md_sync(struct drbd_conf *mdev)
3352 struct meta_data_on_disk *buffer;
3356 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
3358 del_timer(&mdev->md_sync_timer);
3360 /* We use here D_FAILED and not D_ATTACHING because we try to write
3361 * metadata even if we detach due to a disk failure! */
3362 if (!get_ldev_if_state(mdev, D_FAILED))
3365 mutex_lock(&mdev->md_io_mutex);
3366 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3367 memset(buffer, 0, 512);
3369 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
3370 for (i = UI_CURRENT; i < UI_SIZE; i++)
3371 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
3372 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
3373 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
3375 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
3376 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
3377 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
3378 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
3379 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
3381 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
3383 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
3384 sector = mdev->ldev->md.md_offset;
3386 if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
3387 clear_bit(MD_DIRTY, &mdev->flags);
3389 /* this was a try anyways ... */
3390 dev_err(DEV, "meta data update failed!\n");
3392 drbd_chk_io_error(mdev, 1, TRUE);
3395 /* Update mdev->ldev->md.la_size_sect,
3396 * since we updated it on metadata. */
3397 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
3399 mutex_unlock(&mdev->md_io_mutex);
3404 * drbd_md_read() - Reads in the meta data super block
3405 * @mdev: DRBD device.
3406 * @bdev: Device from which the meta data should be read in.
3408 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_codes in case
3409 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
3411 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
3413 struct meta_data_on_disk *buffer;
3414 int i, rv = NO_ERROR;
3416 if (!get_ldev_if_state(mdev, D_ATTACHING))
3417 return ERR_IO_MD_DISK;
3419 mutex_lock(&mdev->md_io_mutex);
3420 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3422 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
3423 /* NOTE: cant do normal error processing here as this is
3424 called BEFORE disk is attached */
3425 dev_err(DEV, "Error while reading metadata.\n");
3426 rv = ERR_IO_MD_DISK;
3430 if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) {
3431 dev_err(DEV, "Error while reading metadata, magic not found.\n");
3432 rv = ERR_MD_INVALID;
3435 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
3436 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
3437 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
3438 rv = ERR_MD_INVALID;
3441 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
3442 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
3443 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
3444 rv = ERR_MD_INVALID;
3447 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
3448 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
3449 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
3450 rv = ERR_MD_INVALID;
3454 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
3455 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
3456 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
3457 rv = ERR_MD_INVALID;
3461 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
3462 for (i = UI_CURRENT; i < UI_SIZE; i++)
3463 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
3464 bdev->md.flags = be32_to_cpu(buffer->flags);
3465 mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents);
3466 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
3468 if (mdev->sync_conf.al_extents < 7)
3469 mdev->sync_conf.al_extents = 127;
3472 mutex_unlock(&mdev->md_io_mutex);
3479 * drbd_md_mark_dirty() - Mark meta data super block as dirty
3480 * @mdev: DRBD device.
3482 * Call this function if you change anything that should be written to
3483 * the meta-data super block. This function sets MD_DIRTY, and starts a
3484 * timer that ensures that within five seconds you have to call drbd_md_sync().
3486 void drbd_md_mark_dirty(struct drbd_conf *mdev)
3488 set_bit(MD_DIRTY, &mdev->flags);
3489 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
3493 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
3497 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
3498 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
3501 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3503 if (idx == UI_CURRENT) {
3504 if (mdev->state.role == R_PRIMARY)
3509 drbd_set_ed_uuid(mdev, val);
3512 mdev->ldev->md.uuid[idx] = val;
3513 drbd_md_mark_dirty(mdev);
3517 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3519 if (mdev->ldev->md.uuid[idx]) {
3520 drbd_uuid_move_history(mdev);
3521 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
3523 _drbd_uuid_set(mdev, idx, val);
3527 * drbd_uuid_new_current() - Creates a new current UUID
3528 * @mdev: DRBD device.
3530 * Creates a new current UUID, and rotates the old current UUID into
3531 * the bitmap slot. Causes an incremental resync upon next connect.
3533 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
3537 dev_info(DEV, "Creating new current UUID\n");
3538 D_ASSERT(mdev->ldev->md.uuid[UI_BITMAP] == 0);
3539 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
3541 get_random_bytes(&val, sizeof(u64));
3542 _drbd_uuid_set(mdev, UI_CURRENT, val);
3545 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
3547 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
3551 drbd_uuid_move_history(mdev);
3552 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
3553 mdev->ldev->md.uuid[UI_BITMAP] = 0;
3555 if (mdev->ldev->md.uuid[UI_BITMAP])
3556 dev_warn(DEV, "bm UUID already set");
3558 mdev->ldev->md.uuid[UI_BITMAP] = val;
3559 mdev->ldev->md.uuid[UI_BITMAP] &= ~((u64)1);
3562 drbd_md_mark_dirty(mdev);
3566 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3567 * @mdev: DRBD device.
3569 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
3571 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
3575 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3576 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
3578 drbd_bm_set_all(mdev);
3580 rv = drbd_bm_write(mdev);
3583 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
3594 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3595 * @mdev: DRBD device.
3597 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
3599 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
3603 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3604 drbd_bm_clear_all(mdev);
3605 rv = drbd_bm_write(mdev);
3612 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3614 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
3617 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
3619 drbd_bm_lock(mdev, work->why);
3620 rv = work->io_fn(mdev);
3621 drbd_bm_unlock(mdev);
3623 clear_bit(BITMAP_IO, &mdev->flags);
3624 wake_up(&mdev->misc_wait);
3627 work->done(mdev, rv);
3629 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
3636 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
3637 * @mdev: DRBD device.
3638 * @io_fn: IO callback to be called when bitmap IO is possible
3639 * @done: callback to be called after the bitmap IO was performed
3640 * @why: Descriptive text of the reason for doing the IO
3642 * While IO on the bitmap happens we freeze application IO thus we ensure
3643 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
3644 * called from worker context. It MUST NOT be used while a previous such
3645 * work is still pending!
3647 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
3648 int (*io_fn)(struct drbd_conf *),
3649 void (*done)(struct drbd_conf *, int),
3652 D_ASSERT(current == mdev->worker.task);
3654 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
3655 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
3656 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
3657 if (mdev->bm_io_work.why)
3658 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
3659 why, mdev->bm_io_work.why);
3661 mdev->bm_io_work.io_fn = io_fn;
3662 mdev->bm_io_work.done = done;
3663 mdev->bm_io_work.why = why;
3665 set_bit(BITMAP_IO, &mdev->flags);
3666 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
3667 if (list_empty(&mdev->bm_io_work.w.list)) {
3668 set_bit(BITMAP_IO_QUEUED, &mdev->flags);
3669 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
3671 dev_err(DEV, "FIXME avoided double queuing bm_io_work\n");
3676 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
3677 * @mdev: DRBD device.
3678 * @io_fn: IO callback to be called when bitmap IO is possible
3679 * @why: Descriptive text of the reason for doing the IO
3681 * freezes application IO while that the actual IO operations runs. This
3682 * functions MAY NOT be called from worker context.
3684 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why)
3688 D_ASSERT(current != mdev->worker.task);
3690 drbd_suspend_io(mdev);
3692 drbd_bm_lock(mdev, why);
3694 drbd_bm_unlock(mdev);
3696 drbd_resume_io(mdev);
3701 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3703 if ((mdev->ldev->md.flags & flag) != flag) {
3704 drbd_md_mark_dirty(mdev);
3705 mdev->ldev->md.flags |= flag;
3709 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3711 if ((mdev->ldev->md.flags & flag) != 0) {
3712 drbd_md_mark_dirty(mdev);
3713 mdev->ldev->md.flags &= ~flag;
3716 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
3718 return (bdev->md.flags & flag) != 0;
3721 static void md_sync_timer_fn(unsigned long data)
3723 struct drbd_conf *mdev = (struct drbd_conf *) data;
3725 drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work);
3728 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3730 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3736 #ifdef CONFIG_DRBD_FAULT_INJECTION
3737 /* Fault insertion support including random number generator shamelessly
3738 * stolen from kernel/rcutorture.c */
3739 struct fault_random_state {
3740 unsigned long state;
3741 unsigned long count;
3744 #define FAULT_RANDOM_MULT 39916801 /* prime */
3745 #define FAULT_RANDOM_ADD 479001701 /* prime */
3746 #define FAULT_RANDOM_REFRESH 10000
3749 * Crude but fast random-number generator. Uses a linear congruential
3750 * generator, with occasional help from get_random_bytes().
3752 static unsigned long
3753 _drbd_fault_random(struct fault_random_state *rsp)
3757 if (!rsp->count--) {
3758 get_random_bytes(&refresh, sizeof(refresh));
3759 rsp->state += refresh;
3760 rsp->count = FAULT_RANDOM_REFRESH;
3762 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
3763 return swahw32(rsp->state);
3767 _drbd_fault_str(unsigned int type) {
3768 static char *_faults[] = {
3769 [DRBD_FAULT_MD_WR] = "Meta-data write",
3770 [DRBD_FAULT_MD_RD] = "Meta-data read",
3771 [DRBD_FAULT_RS_WR] = "Resync write",
3772 [DRBD_FAULT_RS_RD] = "Resync read",
3773 [DRBD_FAULT_DT_WR] = "Data write",
3774 [DRBD_FAULT_DT_RD] = "Data read",
3775 [DRBD_FAULT_DT_RA] = "Data read ahead",
3776 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
3777 [DRBD_FAULT_AL_EE] = "EE allocation",
3778 [DRBD_FAULT_RECEIVE] = "receive data corruption",
3781 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
3785 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
3787 static struct fault_random_state rrs = {0, 0};
3789 unsigned int ret = (
3791 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
3792 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
3797 if (printk_ratelimit())
3798 dev_warn(DEV, "***Simulating %s failure\n",
3799 _drbd_fault_str(type));
3806 const char *drbd_buildtag(void)
3808 /* DRBD built from external sources has here a reference to the
3809 git hash of the source code. */
3811 static char buildtag[38] = "\0uilt-in";
3813 if (buildtag[0] == 0) {
3814 #ifdef CONFIG_MODULES
3815 if (THIS_MODULE != NULL)
3816 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
3825 module_init(drbd_init)
3826 module_exit(drbd_cleanup)
3828 EXPORT_SYMBOL(drbd_conn_str);
3829 EXPORT_SYMBOL(drbd_role_str);
3830 EXPORT_SYMBOL(drbd_disk_str);
3831 EXPORT_SYMBOL(drbd_set_st_err_str);