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 drbd_uuid_new_current(mdev);
1222 drbd_send_uuids(mdev);
1228 if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) {
1229 if (ns.peer == R_PRIMARY && mdev->ldev->md.uuid[UI_BITMAP] == 0)
1230 drbd_uuid_new_current(mdev);
1232 /* D_DISKLESS Peer becomes secondary */
1233 if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
1234 drbd_al_to_on_disk_bm(mdev);
1238 /* Last part of the attaching process ... */
1239 if (ns.conn >= C_CONNECTED &&
1240 os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
1241 kfree(mdev->p_uuid); /* We expect to receive up-to-date UUIDs soon. */
1242 mdev->p_uuid = NULL; /* ...to not use the old ones in the mean time */
1243 drbd_send_sizes(mdev, 0, 0); /* to start sync... */
1244 drbd_send_uuids(mdev);
1245 drbd_send_state(mdev);
1248 /* We want to pause/continue resync, tell peer. */
1249 if (ns.conn >= C_CONNECTED &&
1250 ((os.aftr_isp != ns.aftr_isp) ||
1251 (os.user_isp != ns.user_isp)))
1252 drbd_send_state(mdev);
1254 /* In case one of the isp bits got set, suspend other devices. */
1255 if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
1256 (ns.aftr_isp || ns.peer_isp || ns.user_isp))
1257 suspend_other_sg(mdev);
1259 /* Make sure the peer gets informed about eventual state
1260 changes (ISP bits) while we were in WFReportParams. */
1261 if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
1262 drbd_send_state(mdev);
1264 /* We are in the progress to start a full sync... */
1265 if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
1266 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S))
1267 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, &abw_start_sync, "set_n_write from StartingSync");
1269 /* We are invalidating our self... */
1270 if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED &&
1271 os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT)
1272 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL, "set_n_write from invalidate");
1274 if (os.disk > D_FAILED && ns.disk == D_FAILED) {
1275 enum drbd_io_error_p eh;
1278 if (get_ldev_if_state(mdev, D_FAILED)) {
1279 eh = mdev->ldev->dc.on_io_error;
1283 drbd_rs_cancel_all(mdev);
1284 /* since get_ldev() only works as long as disk>=D_INCONSISTENT,
1285 and it is D_DISKLESS here, local_cnt can only go down, it can
1286 not increase... It will reach zero */
1287 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1289 mdev->rs_failed = 0;
1290 atomic_set(&mdev->rs_pending_cnt, 0);
1292 spin_lock_irq(&mdev->req_lock);
1293 _drbd_set_state(_NS(mdev, disk, D_DISKLESS), CS_HARD, NULL);
1294 spin_unlock_irq(&mdev->req_lock);
1296 if (eh == EP_CALL_HELPER)
1297 drbd_khelper(mdev, "local-io-error");
1300 if (os.disk > D_DISKLESS && ns.disk == D_DISKLESS) {
1302 if (os.disk == D_FAILED) /* && ns.disk == D_DISKLESS*/ {
1303 if (drbd_send_state(mdev))
1304 dev_warn(DEV, "Notified peer that my disk is broken.\n");
1306 dev_err(DEV, "Sending state in drbd_io_error() failed\n");
1309 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1310 lc_destroy(mdev->resync);
1311 mdev->resync = NULL;
1312 lc_destroy(mdev->act_log);
1313 mdev->act_log = NULL;
1315 drbd_free_bc(mdev->ldev);
1316 mdev->ldev = NULL;);
1318 if (mdev->md_io_tmpp)
1319 __free_page(mdev->md_io_tmpp);
1322 /* Disks got bigger while they were detached */
1323 if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
1324 test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) {
1325 if (ns.conn == C_CONNECTED)
1326 resync_after_online_grow(mdev);
1329 /* A resync finished or aborted, wake paused devices... */
1330 if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) ||
1331 (os.peer_isp && !ns.peer_isp) ||
1332 (os.user_isp && !ns.user_isp))
1333 resume_next_sg(mdev);
1335 /* Upon network connection, we need to start the receiver */
1336 if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED)
1337 drbd_thread_start(&mdev->receiver);
1339 /* Terminate worker thread if we are unconfigured - it will be
1340 restarted as needed... */
1341 if (ns.disk == D_DISKLESS &&
1342 ns.conn == C_STANDALONE &&
1343 ns.role == R_SECONDARY) {
1344 if (os.aftr_isp != ns.aftr_isp)
1345 resume_next_sg(mdev);
1346 /* set in __drbd_set_state, unless CONFIG_PENDING was set */
1347 if (test_bit(DEVICE_DYING, &mdev->flags))
1348 drbd_thread_stop_nowait(&mdev->worker);
1355 static int drbd_thread_setup(void *arg)
1357 struct drbd_thread *thi = (struct drbd_thread *) arg;
1358 struct drbd_conf *mdev = thi->mdev;
1359 unsigned long flags;
1363 retval = thi->function(thi);
1365 spin_lock_irqsave(&thi->t_lock, flags);
1367 /* if the receiver has been "Exiting", the last thing it did
1368 * was set the conn state to "StandAlone",
1369 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
1370 * and receiver thread will be "started".
1371 * drbd_thread_start needs to set "Restarting" in that case.
1372 * t_state check and assignment needs to be within the same spinlock,
1373 * so either thread_start sees Exiting, and can remap to Restarting,
1374 * or thread_start see None, and can proceed as normal.
1377 if (thi->t_state == Restarting) {
1378 dev_info(DEV, "Restarting %s\n", current->comm);
1379 thi->t_state = Running;
1380 spin_unlock_irqrestore(&thi->t_lock, flags);
1385 thi->t_state = None;
1387 complete(&thi->stop);
1388 spin_unlock_irqrestore(&thi->t_lock, flags);
1390 dev_info(DEV, "Terminating %s\n", current->comm);
1392 /* Release mod reference taken when thread was started */
1393 module_put(THIS_MODULE);
1397 static void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi,
1398 int (*func) (struct drbd_thread *))
1400 spin_lock_init(&thi->t_lock);
1402 thi->t_state = None;
1403 thi->function = func;
1407 int drbd_thread_start(struct drbd_thread *thi)
1409 struct drbd_conf *mdev = thi->mdev;
1410 struct task_struct *nt;
1411 unsigned long flags;
1414 thi == &mdev->receiver ? "receiver" :
1415 thi == &mdev->asender ? "asender" :
1416 thi == &mdev->worker ? "worker" : "NONSENSE";
1418 /* is used from state engine doing drbd_thread_stop_nowait,
1419 * while holding the req lock irqsave */
1420 spin_lock_irqsave(&thi->t_lock, flags);
1422 switch (thi->t_state) {
1424 dev_info(DEV, "Starting %s thread (from %s [%d])\n",
1425 me, current->comm, current->pid);
1427 /* Get ref on module for thread - this is released when thread exits */
1428 if (!try_module_get(THIS_MODULE)) {
1429 dev_err(DEV, "Failed to get module reference in drbd_thread_start\n");
1430 spin_unlock_irqrestore(&thi->t_lock, flags);
1434 init_completion(&thi->stop);
1435 D_ASSERT(thi->task == NULL);
1436 thi->reset_cpu_mask = 1;
1437 thi->t_state = Running;
1438 spin_unlock_irqrestore(&thi->t_lock, flags);
1439 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
1441 nt = kthread_create(drbd_thread_setup, (void *) thi,
1442 "drbd%d_%s", mdev_to_minor(mdev), me);
1445 dev_err(DEV, "Couldn't start thread\n");
1447 module_put(THIS_MODULE);
1450 spin_lock_irqsave(&thi->t_lock, flags);
1452 thi->t_state = Running;
1453 spin_unlock_irqrestore(&thi->t_lock, flags);
1454 wake_up_process(nt);
1457 thi->t_state = Restarting;
1458 dev_info(DEV, "Restarting %s thread (from %s [%d])\n",
1459 me, current->comm, current->pid);
1464 spin_unlock_irqrestore(&thi->t_lock, flags);
1472 void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
1474 unsigned long flags;
1476 enum drbd_thread_state ns = restart ? Restarting : Exiting;
1478 /* may be called from state engine, holding the req lock irqsave */
1479 spin_lock_irqsave(&thi->t_lock, flags);
1481 if (thi->t_state == None) {
1482 spin_unlock_irqrestore(&thi->t_lock, flags);
1484 drbd_thread_start(thi);
1488 if (thi->t_state != ns) {
1489 if (thi->task == NULL) {
1490 spin_unlock_irqrestore(&thi->t_lock, flags);
1496 init_completion(&thi->stop);
1497 if (thi->task != current)
1498 force_sig(DRBD_SIGKILL, thi->task);
1502 spin_unlock_irqrestore(&thi->t_lock, flags);
1505 wait_for_completion(&thi->stop);
1510 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
1511 * @mdev: DRBD device.
1513 * Forces all threads of a device onto the same CPU. This is beneficial for
1514 * DRBD's performance. May be overwritten by user's configuration.
1516 void drbd_calc_cpu_mask(struct drbd_conf *mdev)
1520 /* user override. */
1521 if (cpumask_weight(mdev->cpu_mask))
1524 ord = mdev_to_minor(mdev) % cpumask_weight(cpu_online_mask);
1525 for_each_online_cpu(cpu) {
1527 cpumask_set_cpu(cpu, mdev->cpu_mask);
1531 /* should not be reached */
1532 cpumask_setall(mdev->cpu_mask);
1536 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
1537 * @mdev: DRBD device.
1539 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
1542 void drbd_thread_current_set_cpu(struct drbd_conf *mdev)
1544 struct task_struct *p = current;
1545 struct drbd_thread *thi =
1546 p == mdev->asender.task ? &mdev->asender :
1547 p == mdev->receiver.task ? &mdev->receiver :
1548 p == mdev->worker.task ? &mdev->worker :
1552 if (!thi->reset_cpu_mask)
1554 thi->reset_cpu_mask = 0;
1555 set_cpus_allowed_ptr(p, mdev->cpu_mask);
1559 /* the appropriate socket mutex must be held already */
1560 int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1561 enum drbd_packets cmd, struct p_header *h,
1562 size_t size, unsigned msg_flags)
1566 ERR_IF(!h) return FALSE;
1567 ERR_IF(!size) return FALSE;
1569 h->magic = BE_DRBD_MAGIC;
1570 h->command = cpu_to_be16(cmd);
1571 h->length = cpu_to_be16(size-sizeof(struct p_header));
1573 sent = drbd_send(mdev, sock, h, size, msg_flags);
1575 ok = (sent == size);
1577 dev_err(DEV, "short sent %s size=%d sent=%d\n",
1578 cmdname(cmd), (int)size, sent);
1582 /* don't pass the socket. we may only look at it
1583 * when we hold the appropriate socket mutex.
1585 int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1586 enum drbd_packets cmd, struct p_header *h, size_t size)
1589 struct socket *sock;
1591 if (use_data_socket) {
1592 mutex_lock(&mdev->data.mutex);
1593 sock = mdev->data.socket;
1595 mutex_lock(&mdev->meta.mutex);
1596 sock = mdev->meta.socket;
1599 /* drbd_disconnect() could have called drbd_free_sock()
1600 * while we were waiting in down()... */
1601 if (likely(sock != NULL))
1602 ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0);
1604 if (use_data_socket)
1605 mutex_unlock(&mdev->data.mutex);
1607 mutex_unlock(&mdev->meta.mutex);
1611 int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
1617 h.magic = BE_DRBD_MAGIC;
1618 h.command = cpu_to_be16(cmd);
1619 h.length = cpu_to_be16(size);
1621 if (!drbd_get_data_sock(mdev))
1625 drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0));
1627 drbd_send(mdev, mdev->data.socket, data, size, 0));
1629 drbd_put_data_sock(mdev);
1634 int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc)
1636 struct p_rs_param_89 *p;
1637 struct socket *sock;
1639 const int apv = mdev->agreed_pro_version;
1641 size = apv <= 87 ? sizeof(struct p_rs_param)
1642 : apv == 88 ? sizeof(struct p_rs_param)
1643 + strlen(mdev->sync_conf.verify_alg) + 1
1644 : /* 89 */ sizeof(struct p_rs_param_89);
1646 /* used from admin command context and receiver/worker context.
1647 * to avoid kmalloc, grab the socket right here,
1648 * then use the pre-allocated sbuf there */
1649 mutex_lock(&mdev->data.mutex);
1650 sock = mdev->data.socket;
1652 if (likely(sock != NULL)) {
1653 enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
1655 p = &mdev->data.sbuf.rs_param_89;
1657 /* initialize verify_alg and csums_alg */
1658 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
1660 p->rate = cpu_to_be32(sc->rate);
1663 strcpy(p->verify_alg, mdev->sync_conf.verify_alg);
1665 strcpy(p->csums_alg, mdev->sync_conf.csums_alg);
1667 rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
1669 rv = 0; /* not ok */
1671 mutex_unlock(&mdev->data.mutex);
1676 int drbd_send_protocol(struct drbd_conf *mdev)
1678 struct p_protocol *p;
1681 size = sizeof(struct p_protocol);
1683 if (mdev->agreed_pro_version >= 87)
1684 size += strlen(mdev->net_conf->integrity_alg) + 1;
1686 /* we must not recurse into our own queue,
1687 * as that is blocked during handshake */
1688 p = kmalloc(size, GFP_NOIO);
1692 p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol);
1693 p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p);
1694 p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p);
1695 p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p);
1696 p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries);
1699 if (mdev->net_conf->want_lose)
1701 if (mdev->net_conf->dry_run) {
1702 if (mdev->agreed_pro_version >= 92)
1705 dev_err(DEV, "--dry-run is not supported by peer");
1710 p->conn_flags = cpu_to_be32(cf);
1712 if (mdev->agreed_pro_version >= 87)
1713 strcpy(p->integrity_alg, mdev->net_conf->integrity_alg);
1715 rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL,
1716 (struct p_header *)p, size);
1721 int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
1726 if (!get_ldev_if_state(mdev, D_NEGOTIATING))
1729 for (i = UI_CURRENT; i < UI_SIZE; i++)
1730 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
1732 mdev->comm_bm_set = drbd_bm_total_weight(mdev);
1733 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
1734 uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
1735 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
1736 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
1737 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
1741 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS,
1742 (struct p_header *)&p, sizeof(p));
1745 int drbd_send_uuids(struct drbd_conf *mdev)
1747 return _drbd_send_uuids(mdev, 0);
1750 int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
1752 return _drbd_send_uuids(mdev, 8);
1756 int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val)
1760 p.uuid = cpu_to_be64(val);
1762 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID,
1763 (struct p_header *)&p, sizeof(p));
1766 int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags)
1769 sector_t d_size, u_size;
1773 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
1774 D_ASSERT(mdev->ldev->backing_bdev);
1775 d_size = drbd_get_max_capacity(mdev->ldev);
1776 u_size = mdev->ldev->dc.disk_size;
1777 q_order_type = drbd_queue_order_type(mdev);
1782 q_order_type = QUEUE_ORDERED_NONE;
1785 p.d_size = cpu_to_be64(d_size);
1786 p.u_size = cpu_to_be64(u_size);
1787 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
1788 p.max_segment_size = cpu_to_be32(queue_max_segment_size(mdev->rq_queue));
1789 p.queue_order_type = cpu_to_be16(q_order_type);
1790 p.dds_flags = cpu_to_be16(flags);
1792 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES,
1793 (struct p_header *)&p, sizeof(p));
1798 * drbd_send_state() - Sends the drbd state to the peer
1799 * @mdev: DRBD device.
1801 int drbd_send_state(struct drbd_conf *mdev)
1803 struct socket *sock;
1807 /* Grab state lock so we wont send state if we're in the middle
1808 * of a cluster wide state change on another thread */
1809 drbd_state_lock(mdev);
1811 mutex_lock(&mdev->data.mutex);
1813 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
1814 sock = mdev->data.socket;
1816 if (likely(sock != NULL)) {
1817 ok = _drbd_send_cmd(mdev, sock, P_STATE,
1818 (struct p_header *)&p, sizeof(p), 0);
1821 mutex_unlock(&mdev->data.mutex);
1823 drbd_state_unlock(mdev);
1827 int drbd_send_state_req(struct drbd_conf *mdev,
1828 union drbd_state mask, union drbd_state val)
1830 struct p_req_state p;
1832 p.mask = cpu_to_be32(mask.i);
1833 p.val = cpu_to_be32(val.i);
1835 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ,
1836 (struct p_header *)&p, sizeof(p));
1839 int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode)
1841 struct p_req_state_reply p;
1843 p.retcode = cpu_to_be32(retcode);
1845 return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY,
1846 (struct p_header *)&p, sizeof(p));
1849 int fill_bitmap_rle_bits(struct drbd_conf *mdev,
1850 struct p_compressed_bm *p,
1851 struct bm_xfer_ctx *c)
1853 struct bitstream bs;
1854 unsigned long plain_bits;
1861 /* may we use this feature? */
1862 if ((mdev->sync_conf.use_rle == 0) ||
1863 (mdev->agreed_pro_version < 90))
1866 if (c->bit_offset >= c->bm_bits)
1867 return 0; /* nothing to do. */
1869 /* use at most thus many bytes */
1870 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
1871 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
1872 /* plain bits covered in this code string */
1875 /* p->encoding & 0x80 stores whether the first run length is set.
1876 * bit offset is implicit.
1877 * start with toggle == 2 to be able to tell the first iteration */
1880 /* see how much plain bits we can stuff into one packet
1881 * using RLE and VLI. */
1883 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
1884 : _drbd_bm_find_next(mdev, c->bit_offset);
1887 rl = tmp - c->bit_offset;
1889 if (toggle == 2) { /* first iteration */
1891 /* the first checked bit was set,
1892 * store start value, */
1893 DCBP_set_start(p, 1);
1894 /* but skip encoding of zero run length */
1898 DCBP_set_start(p, 0);
1901 /* paranoia: catch zero runlength.
1902 * can only happen if bitmap is modified while we scan it. */
1904 dev_err(DEV, "unexpected zero runlength while encoding bitmap "
1905 "t:%u bo:%lu\n", toggle, c->bit_offset);
1909 bits = vli_encode_bits(&bs, rl);
1910 if (bits == -ENOBUFS) /* buffer full */
1913 dev_err(DEV, "error while encoding bitmap: %d\n", bits);
1919 c->bit_offset = tmp;
1920 } while (c->bit_offset < c->bm_bits);
1922 len = bs.cur.b - p->code + !!bs.cur.bit;
1924 if (plain_bits < (len << 3)) {
1925 /* incompressible with this method.
1926 * we need to rewind both word and bit position. */
1927 c->bit_offset -= plain_bits;
1928 bm_xfer_ctx_bit_to_word_offset(c);
1929 c->bit_offset = c->word_offset * BITS_PER_LONG;
1933 /* RLE + VLI was able to compress it just fine.
1934 * update c->word_offset. */
1935 bm_xfer_ctx_bit_to_word_offset(c);
1937 /* store pad_bits */
1938 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
1943 enum { OK, FAILED, DONE }
1944 send_bitmap_rle_or_plain(struct drbd_conf *mdev,
1945 struct p_header *h, struct bm_xfer_ctx *c)
1947 struct p_compressed_bm *p = (void*)h;
1948 unsigned long num_words;
1952 len = fill_bitmap_rle_bits(mdev, p, c);
1958 DCBP_set_code(p, RLE_VLI_Bits);
1959 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h,
1960 sizeof(*p) + len, 0);
1963 c->bytes[0] += sizeof(*p) + len;
1965 if (c->bit_offset >= c->bm_bits)
1968 /* was not compressible.
1969 * send a buffer full of plain text bits instead. */
1970 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
1971 len = num_words * sizeof(long);
1973 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
1974 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP,
1975 h, sizeof(struct p_header) + len, 0);
1976 c->word_offset += num_words;
1977 c->bit_offset = c->word_offset * BITS_PER_LONG;
1980 c->bytes[1] += sizeof(struct p_header) + len;
1982 if (c->bit_offset > c->bm_bits)
1983 c->bit_offset = c->bm_bits;
1985 ok = ok ? ((len == 0) ? DONE : OK) : FAILED;
1988 INFO_bm_xfer_stats(mdev, "send", c);
1992 /* See the comment at receive_bitmap() */
1993 int _drbd_send_bitmap(struct drbd_conf *mdev)
1995 struct bm_xfer_ctx c;
1999 ERR_IF(!mdev->bitmap) return FALSE;
2001 /* maybe we should use some per thread scratch page,
2002 * and allocate that during initial device creation? */
2003 p = (struct p_header *) __get_free_page(GFP_NOIO);
2005 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
2009 if (get_ldev(mdev)) {
2010 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
2011 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
2012 drbd_bm_set_all(mdev);
2013 if (drbd_bm_write(mdev)) {
2014 /* write_bm did fail! Leave full sync flag set in Meta P_DATA
2015 * but otherwise process as per normal - need to tell other
2016 * side that a full resync is required! */
2017 dev_err(DEV, "Failed to write bitmap to disk!\n");
2019 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2026 c = (struct bm_xfer_ctx) {
2027 .bm_bits = drbd_bm_bits(mdev),
2028 .bm_words = drbd_bm_words(mdev),
2032 ret = send_bitmap_rle_or_plain(mdev, p, &c);
2033 } while (ret == OK);
2035 free_page((unsigned long) p);
2036 return (ret == DONE);
2039 int drbd_send_bitmap(struct drbd_conf *mdev)
2043 if (!drbd_get_data_sock(mdev))
2045 err = !_drbd_send_bitmap(mdev);
2046 drbd_put_data_sock(mdev);
2050 int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
2053 struct p_barrier_ack p;
2055 p.barrier = barrier_nr;
2056 p.set_size = cpu_to_be32(set_size);
2058 if (mdev->state.conn < C_CONNECTED)
2060 ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK,
2061 (struct p_header *)&p, sizeof(p));
2066 * _drbd_send_ack() - Sends an ack packet
2067 * @mdev: DRBD device.
2068 * @cmd: Packet command code.
2069 * @sector: sector, needs to be in big endian byte order
2070 * @blksize: size in byte, needs to be in big endian byte order
2071 * @block_id: Id, big endian byte order
2073 static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
2079 struct p_block_ack p;
2082 p.block_id = block_id;
2083 p.blksize = blksize;
2084 p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq));
2086 if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED)
2088 ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd,
2089 (struct p_header *)&p, sizeof(p));
2093 int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
2096 const int header_size = sizeof(struct p_data)
2097 - sizeof(struct p_header);
2098 int data_size = ((struct p_header *)dp)->length - header_size;
2100 return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
2104 int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
2105 struct p_block_req *rp)
2107 return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
2111 * drbd_send_ack() - Sends an ack packet
2112 * @mdev: DRBD device.
2113 * @cmd: Packet command code.
2116 int drbd_send_ack(struct drbd_conf *mdev,
2117 enum drbd_packets cmd, struct drbd_epoch_entry *e)
2119 return _drbd_send_ack(mdev, cmd,
2120 cpu_to_be64(e->sector),
2121 cpu_to_be32(e->size),
2125 /* This function misuses the block_id field to signal if the blocks
2126 * are is sync or not. */
2127 int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
2128 sector_t sector, int blksize, u64 block_id)
2130 return _drbd_send_ack(mdev, cmd,
2131 cpu_to_be64(sector),
2132 cpu_to_be32(blksize),
2133 cpu_to_be64(block_id));
2136 int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
2137 sector_t sector, int size, u64 block_id)
2140 struct p_block_req p;
2142 p.sector = cpu_to_be64(sector);
2143 p.block_id = block_id;
2144 p.blksize = cpu_to_be32(size);
2146 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd,
2147 (struct p_header *)&p, sizeof(p));
2151 int drbd_send_drequest_csum(struct drbd_conf *mdev,
2152 sector_t sector, int size,
2153 void *digest, int digest_size,
2154 enum drbd_packets cmd)
2157 struct p_block_req p;
2159 p.sector = cpu_to_be64(sector);
2160 p.block_id = BE_DRBD_MAGIC + 0xbeef;
2161 p.blksize = cpu_to_be32(size);
2163 p.head.magic = BE_DRBD_MAGIC;
2164 p.head.command = cpu_to_be16(cmd);
2165 p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header) + digest_size);
2167 mutex_lock(&mdev->data.mutex);
2169 ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0));
2170 ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0));
2172 mutex_unlock(&mdev->data.mutex);
2177 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
2180 struct p_block_req p;
2182 p.sector = cpu_to_be64(sector);
2183 p.block_id = BE_DRBD_MAGIC + 0xbabe;
2184 p.blksize = cpu_to_be32(size);
2186 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST,
2187 (struct p_header *)&p, sizeof(p));
2191 static int drbd_send_delay_probe(struct drbd_conf *mdev, struct drbd_socket *ds)
2193 struct p_delay_probe dp;
2197 mutex_lock(&ds->mutex);
2198 if (likely(ds->socket)) {
2199 do_gettimeofday(&now);
2200 offset = now.tv_usec - mdev->dps_time.tv_usec +
2201 (now.tv_sec - mdev->dps_time.tv_sec) * 1000000;
2202 dp.seq_num = cpu_to_be32(atomic_read(&mdev->delay_seq));
2203 dp.offset = cpu_to_be32(offset);
2205 ok = _drbd_send_cmd(mdev, ds->socket, P_DELAY_PROBE,
2206 (struct p_header *)&dp, sizeof(dp), 0);
2208 mutex_unlock(&ds->mutex);
2213 static int drbd_send_delay_probes(struct drbd_conf *mdev)
2216 atomic_inc(&mdev->delay_seq);
2217 do_gettimeofday(&mdev->dps_time);
2218 ok = drbd_send_delay_probe(mdev, &mdev->meta);
2219 ok = ok && drbd_send_delay_probe(mdev, &mdev->data);
2221 mdev->dp_volume_last = mdev->send_cnt;
2222 mod_timer(&mdev->delay_probe_timer, jiffies + mdev->sync_conf.dp_interval * HZ / 10);
2227 /* called on sndtimeo
2228 * returns FALSE if we should retry,
2229 * TRUE if we think connection is dead
2231 static int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock)
2234 /* long elapsed = (long)(jiffies - mdev->last_received); */
2236 drop_it = mdev->meta.socket == sock
2237 || !mdev->asender.task
2238 || get_t_state(&mdev->asender) != Running
2239 || mdev->state.conn < C_CONNECTED;
2244 drop_it = !--mdev->ko_count;
2246 dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
2247 current->comm, current->pid, mdev->ko_count);
2251 return drop_it; /* && (mdev->state == R_PRIMARY) */;
2254 /* The idea of sendpage seems to be to put some kind of reference
2255 * to the page into the skb, and to hand it over to the NIC. In
2256 * this process get_page() gets called.
2258 * As soon as the page was really sent over the network put_page()
2259 * gets called by some part of the network layer. [ NIC driver? ]
2261 * [ get_page() / put_page() increment/decrement the count. If count
2262 * reaches 0 the page will be freed. ]
2264 * This works nicely with pages from FSs.
2265 * But this means that in protocol A we might signal IO completion too early!
2267 * In order not to corrupt data during a resync we must make sure
2268 * that we do not reuse our own buffer pages (EEs) to early, therefore
2269 * we have the net_ee list.
2271 * XFS seems to have problems, still, it submits pages with page_count == 0!
2272 * As a workaround, we disable sendpage on pages
2273 * with page_count == 0 or PageSlab.
2275 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
2276 int offset, size_t size)
2278 int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, 0);
2281 mdev->send_cnt += size>>9;
2282 return sent == size;
2285 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
2286 int offset, size_t size)
2288 mm_segment_t oldfs = get_fs();
2292 /* e.g. XFS meta- & log-data is in slab pages, which have a
2293 * page_count of 0 and/or have PageSlab() set.
2294 * we cannot use send_page for those, as that does get_page();
2295 * put_page(); and would cause either a VM_BUG directly, or
2296 * __page_cache_release a page that would actually still be referenced
2297 * by someone, leading to some obscure delayed Oops somewhere else. */
2298 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
2299 return _drbd_no_send_page(mdev, page, offset, size);
2301 drbd_update_congested(mdev);
2304 sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page,
2307 if (sent == -EAGAIN) {
2308 if (we_should_drop_the_connection(mdev,
2315 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
2316 __func__, (int)size, len, sent);
2321 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
2323 clear_bit(NET_CONGESTED, &mdev->flags);
2327 mdev->send_cnt += size>>9;
2331 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
2333 struct bio_vec *bvec;
2335 __bio_for_each_segment(bvec, bio, i, 0) {
2336 if (!_drbd_no_send_page(mdev, bvec->bv_page,
2337 bvec->bv_offset, bvec->bv_len))
2343 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
2345 struct bio_vec *bvec;
2347 __bio_for_each_segment(bvec, bio, i, 0) {
2348 if (!_drbd_send_page(mdev, bvec->bv_page,
2349 bvec->bv_offset, bvec->bv_len))
2356 static void consider_delay_probes(struct drbd_conf *mdev)
2358 if (mdev->state.conn != C_SYNC_SOURCE)
2361 if (mdev->dp_volume_last + mdev->sync_conf.dp_volume * 2 < mdev->send_cnt)
2362 drbd_send_delay_probes(mdev);
2365 static int w_delay_probes(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
2367 if (!cancel && mdev->state.conn == C_SYNC_SOURCE)
2368 drbd_send_delay_probes(mdev);
2373 static void delay_probe_timer_fn(unsigned long data)
2375 struct drbd_conf *mdev = (struct drbd_conf *) data;
2377 if (list_empty(&mdev->delay_probe_work.list))
2378 drbd_queue_work(&mdev->data.work, &mdev->delay_probe_work);
2381 /* Used to send write requests
2382 * R_PRIMARY -> Peer (P_DATA)
2384 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
2388 unsigned int dp_flags = 0;
2392 if (!drbd_get_data_sock(mdev))
2395 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2396 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2398 p.head.magic = BE_DRBD_MAGIC;
2399 p.head.command = cpu_to_be16(P_DATA);
2401 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + req->size);
2403 p.sector = cpu_to_be64(req->sector);
2404 p.block_id = (unsigned long)req;
2405 p.seq_num = cpu_to_be32(req->seq_num =
2406 atomic_add_return(1, &mdev->packet_seq));
2409 /* NOTE: no need to check if barriers supported here as we would
2410 * not pass the test in make_request_common in that case
2412 if (bio_rw_flagged(req->master_bio, BIO_RW_BARRIER)) {
2413 dev_err(DEV, "ASSERT FAILED would have set DP_HARDBARRIER\n");
2414 /* dp_flags |= DP_HARDBARRIER; */
2416 if (bio_rw_flagged(req->master_bio, BIO_RW_SYNCIO))
2417 dp_flags |= DP_RW_SYNC;
2418 /* for now handle SYNCIO and UNPLUG
2419 * as if they still were one and the same flag */
2420 if (bio_rw_flagged(req->master_bio, BIO_RW_UNPLUG))
2421 dp_flags |= DP_RW_SYNC;
2422 if (mdev->state.conn >= C_SYNC_SOURCE &&
2423 mdev->state.conn <= C_PAUSED_SYNC_T)
2424 dp_flags |= DP_MAY_SET_IN_SYNC;
2426 p.dp_flags = cpu_to_be32(dp_flags);
2427 set_bit(UNPLUG_REMOTE, &mdev->flags);
2429 drbd_send(mdev, mdev->data.socket, &p, sizeof(p), MSG_MORE));
2431 dgb = mdev->int_dig_out;
2432 drbd_csum(mdev, mdev->integrity_w_tfm, req->master_bio, dgb);
2433 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2436 if (mdev->net_conf->wire_protocol == DRBD_PROT_A)
2437 ok = _drbd_send_bio(mdev, req->master_bio);
2439 ok = _drbd_send_zc_bio(mdev, req->master_bio);
2442 drbd_put_data_sock(mdev);
2445 consider_delay_probes(mdev);
2450 /* answer packet, used to send data back for read requests:
2451 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
2452 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
2454 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
2455 struct drbd_epoch_entry *e)
2462 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2463 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2465 p.head.magic = BE_DRBD_MAGIC;
2466 p.head.command = cpu_to_be16(cmd);
2468 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + e->size);
2470 p.sector = cpu_to_be64(e->sector);
2471 p.block_id = e->block_id;
2472 /* p.seq_num = 0; No sequence numbers here.. */
2474 /* Only called by our kernel thread.
2475 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
2476 * in response to admin command or module unload.
2478 if (!drbd_get_data_sock(mdev))
2481 ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p,
2482 sizeof(p), MSG_MORE);
2484 dgb = mdev->int_dig_out;
2485 drbd_csum(mdev, mdev->integrity_w_tfm, e->private_bio, dgb);
2486 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2489 ok = _drbd_send_zc_bio(mdev, e->private_bio);
2491 drbd_put_data_sock(mdev);
2494 consider_delay_probes(mdev);
2500 drbd_send distinguishes two cases:
2502 Packets sent via the data socket "sock"
2503 and packets sent via the meta data socket "msock"
2506 -----------------+-------------------------+------------------------------
2507 timeout conf.timeout / 2 conf.timeout / 2
2508 timeout action send a ping via msock Abort communication
2509 and close all sockets
2513 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
2515 int drbd_send(struct drbd_conf *mdev, struct socket *sock,
2516 void *buf, size_t size, unsigned msg_flags)
2525 /* THINK if (signal_pending) return ... ? */
2530 msg.msg_name = NULL;
2531 msg.msg_namelen = 0;
2532 msg.msg_control = NULL;
2533 msg.msg_controllen = 0;
2534 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
2536 if (sock == mdev->data.socket) {
2537 mdev->ko_count = mdev->net_conf->ko_count;
2538 drbd_update_congested(mdev);
2542 * tcp_sendmsg does _not_ use its size parameter at all ?
2544 * -EAGAIN on timeout, -EINTR on signal.
2547 * do we need to block DRBD_SIG if sock == &meta.socket ??
2548 * otherwise wake_asender() might interrupt some send_*Ack !
2550 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
2551 if (rv == -EAGAIN) {
2552 if (we_should_drop_the_connection(mdev, sock))
2559 flush_signals(current);
2567 } while (sent < size);
2569 if (sock == mdev->data.socket)
2570 clear_bit(NET_CONGESTED, &mdev->flags);
2573 if (rv != -EAGAIN) {
2574 dev_err(DEV, "%s_sendmsg returned %d\n",
2575 sock == mdev->meta.socket ? "msock" : "sock",
2577 drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE));
2579 drbd_force_state(mdev, NS(conn, C_TIMEOUT));
2585 static int drbd_open(struct block_device *bdev, fmode_t mode)
2587 struct drbd_conf *mdev = bdev->bd_disk->private_data;
2588 unsigned long flags;
2591 spin_lock_irqsave(&mdev->req_lock, flags);
2592 /* to have a stable mdev->state.role
2593 * and no race with updating open_cnt */
2595 if (mdev->state.role != R_PRIMARY) {
2596 if (mode & FMODE_WRITE)
2598 else if (!allow_oos)
2604 spin_unlock_irqrestore(&mdev->req_lock, flags);
2609 static int drbd_release(struct gendisk *gd, fmode_t mode)
2611 struct drbd_conf *mdev = gd->private_data;
2616 static void drbd_unplug_fn(struct request_queue *q)
2618 struct drbd_conf *mdev = q->queuedata;
2621 spin_lock_irq(q->queue_lock);
2623 spin_unlock_irq(q->queue_lock);
2625 /* only if connected */
2626 spin_lock_irq(&mdev->req_lock);
2627 if (mdev->state.pdsk >= D_INCONSISTENT && mdev->state.conn >= C_CONNECTED) {
2628 D_ASSERT(mdev->state.role == R_PRIMARY);
2629 if (test_and_clear_bit(UNPLUG_REMOTE, &mdev->flags)) {
2630 /* add to the data.work queue,
2631 * unless already queued.
2632 * XXX this might be a good addition to drbd_queue_work
2633 * anyways, to detect "double queuing" ... */
2634 if (list_empty(&mdev->unplug_work.list))
2635 drbd_queue_work(&mdev->data.work,
2636 &mdev->unplug_work);
2639 spin_unlock_irq(&mdev->req_lock);
2641 if (mdev->state.disk >= D_INCONSISTENT)
2645 static void drbd_set_defaults(struct drbd_conf *mdev)
2647 mdev->sync_conf.after = DRBD_AFTER_DEF;
2648 mdev->sync_conf.rate = DRBD_RATE_DEF;
2649 mdev->sync_conf.al_extents = DRBD_AL_EXTENTS_DEF;
2650 mdev->state = (union drbd_state) {
2651 { .role = R_SECONDARY,
2653 .conn = C_STANDALONE,
2660 void drbd_init_set_defaults(struct drbd_conf *mdev)
2662 /* the memset(,0,) did most of this.
2663 * note: only assignments, no allocation in here */
2665 drbd_set_defaults(mdev);
2667 /* for now, we do NOT yet support it,
2668 * even though we start some framework
2669 * to eventually support barriers */
2670 set_bit(NO_BARRIER_SUPP, &mdev->flags);
2672 atomic_set(&mdev->ap_bio_cnt, 0);
2673 atomic_set(&mdev->ap_pending_cnt, 0);
2674 atomic_set(&mdev->rs_pending_cnt, 0);
2675 atomic_set(&mdev->unacked_cnt, 0);
2676 atomic_set(&mdev->local_cnt, 0);
2677 atomic_set(&mdev->net_cnt, 0);
2678 atomic_set(&mdev->packet_seq, 0);
2679 atomic_set(&mdev->pp_in_use, 0);
2680 atomic_set(&mdev->delay_seq, 0);
2682 mutex_init(&mdev->md_io_mutex);
2683 mutex_init(&mdev->data.mutex);
2684 mutex_init(&mdev->meta.mutex);
2685 sema_init(&mdev->data.work.s, 0);
2686 sema_init(&mdev->meta.work.s, 0);
2687 mutex_init(&mdev->state_mutex);
2689 spin_lock_init(&mdev->data.work.q_lock);
2690 spin_lock_init(&mdev->meta.work.q_lock);
2692 spin_lock_init(&mdev->al_lock);
2693 spin_lock_init(&mdev->req_lock);
2694 spin_lock_init(&mdev->peer_seq_lock);
2695 spin_lock_init(&mdev->epoch_lock);
2697 INIT_LIST_HEAD(&mdev->active_ee);
2698 INIT_LIST_HEAD(&mdev->sync_ee);
2699 INIT_LIST_HEAD(&mdev->done_ee);
2700 INIT_LIST_HEAD(&mdev->read_ee);
2701 INIT_LIST_HEAD(&mdev->net_ee);
2702 INIT_LIST_HEAD(&mdev->resync_reads);
2703 INIT_LIST_HEAD(&mdev->data.work.q);
2704 INIT_LIST_HEAD(&mdev->meta.work.q);
2705 INIT_LIST_HEAD(&mdev->resync_work.list);
2706 INIT_LIST_HEAD(&mdev->unplug_work.list);
2707 INIT_LIST_HEAD(&mdev->md_sync_work.list);
2708 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
2709 INIT_LIST_HEAD(&mdev->delay_probes);
2710 INIT_LIST_HEAD(&mdev->delay_probe_work.list);
2712 mdev->resync_work.cb = w_resync_inactive;
2713 mdev->unplug_work.cb = w_send_write_hint;
2714 mdev->md_sync_work.cb = w_md_sync;
2715 mdev->bm_io_work.w.cb = w_bitmap_io;
2716 mdev->delay_probe_work.cb = w_delay_probes;
2717 init_timer(&mdev->resync_timer);
2718 init_timer(&mdev->md_sync_timer);
2719 init_timer(&mdev->delay_probe_timer);
2720 mdev->resync_timer.function = resync_timer_fn;
2721 mdev->resync_timer.data = (unsigned long) mdev;
2722 mdev->md_sync_timer.function = md_sync_timer_fn;
2723 mdev->md_sync_timer.data = (unsigned long) mdev;
2724 mdev->delay_probe_timer.function = delay_probe_timer_fn;
2725 mdev->delay_probe_timer.data = (unsigned long) mdev;
2728 init_waitqueue_head(&mdev->misc_wait);
2729 init_waitqueue_head(&mdev->state_wait);
2730 init_waitqueue_head(&mdev->ee_wait);
2731 init_waitqueue_head(&mdev->al_wait);
2732 init_waitqueue_head(&mdev->seq_wait);
2734 drbd_thread_init(mdev, &mdev->receiver, drbdd_init);
2735 drbd_thread_init(mdev, &mdev->worker, drbd_worker);
2736 drbd_thread_init(mdev, &mdev->asender, drbd_asender);
2738 mdev->agreed_pro_version = PRO_VERSION_MAX;
2739 mdev->write_ordering = WO_bio_barrier;
2740 mdev->resync_wenr = LC_FREE;
2743 void drbd_mdev_cleanup(struct drbd_conf *mdev)
2745 if (mdev->receiver.t_state != None)
2746 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
2747 mdev->receiver.t_state);
2749 /* no need to lock it, I'm the only thread alive */
2750 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
2751 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
2762 mdev->rs_mark_left =
2763 mdev->rs_mark_time = 0;
2764 D_ASSERT(mdev->net_conf == NULL);
2766 drbd_set_my_capacity(mdev, 0);
2768 /* maybe never allocated. */
2769 drbd_bm_resize(mdev, 0, 1);
2770 drbd_bm_cleanup(mdev);
2773 drbd_free_resources(mdev);
2776 * currently we drbd_init_ee only on module load, so
2777 * we may do drbd_release_ee only on module unload!
2779 D_ASSERT(list_empty(&mdev->active_ee));
2780 D_ASSERT(list_empty(&mdev->sync_ee));
2781 D_ASSERT(list_empty(&mdev->done_ee));
2782 D_ASSERT(list_empty(&mdev->read_ee));
2783 D_ASSERT(list_empty(&mdev->net_ee));
2784 D_ASSERT(list_empty(&mdev->resync_reads));
2785 D_ASSERT(list_empty(&mdev->data.work.q));
2786 D_ASSERT(list_empty(&mdev->meta.work.q));
2787 D_ASSERT(list_empty(&mdev->resync_work.list));
2788 D_ASSERT(list_empty(&mdev->unplug_work.list));
2793 static void drbd_destroy_mempools(void)
2797 while (drbd_pp_pool) {
2798 page = drbd_pp_pool;
2799 drbd_pp_pool = (struct page *)page_private(page);
2804 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
2806 if (drbd_ee_mempool)
2807 mempool_destroy(drbd_ee_mempool);
2808 if (drbd_request_mempool)
2809 mempool_destroy(drbd_request_mempool);
2811 kmem_cache_destroy(drbd_ee_cache);
2812 if (drbd_request_cache)
2813 kmem_cache_destroy(drbd_request_cache);
2814 if (drbd_bm_ext_cache)
2815 kmem_cache_destroy(drbd_bm_ext_cache);
2816 if (drbd_al_ext_cache)
2817 kmem_cache_destroy(drbd_al_ext_cache);
2819 drbd_ee_mempool = NULL;
2820 drbd_request_mempool = NULL;
2821 drbd_ee_cache = NULL;
2822 drbd_request_cache = NULL;
2823 drbd_bm_ext_cache = NULL;
2824 drbd_al_ext_cache = NULL;
2829 static int drbd_create_mempools(void)
2832 const int number = (DRBD_MAX_SEGMENT_SIZE/PAGE_SIZE) * minor_count;
2835 /* prepare our caches and mempools */
2836 drbd_request_mempool = NULL;
2837 drbd_ee_cache = NULL;
2838 drbd_request_cache = NULL;
2839 drbd_bm_ext_cache = NULL;
2840 drbd_al_ext_cache = NULL;
2841 drbd_pp_pool = NULL;
2844 drbd_request_cache = kmem_cache_create(
2845 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
2846 if (drbd_request_cache == NULL)
2849 drbd_ee_cache = kmem_cache_create(
2850 "drbd_ee", sizeof(struct drbd_epoch_entry), 0, 0, NULL);
2851 if (drbd_ee_cache == NULL)
2854 drbd_bm_ext_cache = kmem_cache_create(
2855 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
2856 if (drbd_bm_ext_cache == NULL)
2859 drbd_al_ext_cache = kmem_cache_create(
2860 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
2861 if (drbd_al_ext_cache == NULL)
2865 drbd_request_mempool = mempool_create(number,
2866 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
2867 if (drbd_request_mempool == NULL)
2870 drbd_ee_mempool = mempool_create(number,
2871 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2872 if (drbd_request_mempool == NULL)
2875 /* drbd's page pool */
2876 spin_lock_init(&drbd_pp_lock);
2878 for (i = 0; i < number; i++) {
2879 page = alloc_page(GFP_HIGHUSER);
2882 set_page_private(page, (unsigned long)drbd_pp_pool);
2883 drbd_pp_pool = page;
2885 drbd_pp_vacant = number;
2890 drbd_destroy_mempools(); /* in case we allocated some */
2894 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
2897 /* just so we have it. you never know what interesting things we
2898 * might want to do here some day...
2904 static struct notifier_block drbd_notifier = {
2905 .notifier_call = drbd_notify_sys,
2908 static void drbd_release_ee_lists(struct drbd_conf *mdev)
2912 rr = drbd_release_ee(mdev, &mdev->active_ee);
2914 dev_err(DEV, "%d EEs in active list found!\n", rr);
2916 rr = drbd_release_ee(mdev, &mdev->sync_ee);
2918 dev_err(DEV, "%d EEs in sync list found!\n", rr);
2920 rr = drbd_release_ee(mdev, &mdev->read_ee);
2922 dev_err(DEV, "%d EEs in read list found!\n", rr);
2924 rr = drbd_release_ee(mdev, &mdev->done_ee);
2926 dev_err(DEV, "%d EEs in done list found!\n", rr);
2928 rr = drbd_release_ee(mdev, &mdev->net_ee);
2930 dev_err(DEV, "%d EEs in net list found!\n", rr);
2933 /* caution. no locking.
2934 * currently only used from module cleanup code. */
2935 static void drbd_delete_device(unsigned int minor)
2937 struct drbd_conf *mdev = minor_to_mdev(minor);
2942 /* paranoia asserts */
2943 if (mdev->open_cnt != 0)
2944 dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,
2945 __FILE__ , __LINE__);
2947 ERR_IF (!list_empty(&mdev->data.work.q)) {
2948 struct list_head *lp;
2949 list_for_each(lp, &mdev->data.work.q) {
2950 dev_err(DEV, "lp = %p\n", lp);
2953 /* end paranoia asserts */
2955 del_gendisk(mdev->vdisk);
2957 /* cleanup stuff that may have been allocated during
2958 * device (re-)configuration or state changes */
2960 if (mdev->this_bdev)
2961 bdput(mdev->this_bdev);
2963 drbd_free_resources(mdev);
2965 drbd_release_ee_lists(mdev);
2967 /* should be free'd on disconnect? */
2968 kfree(mdev->ee_hash);
2970 mdev->ee_hash_s = 0;
2971 mdev->ee_hash = NULL;
2974 lc_destroy(mdev->act_log);
2975 lc_destroy(mdev->resync);
2977 kfree(mdev->p_uuid);
2978 /* mdev->p_uuid = NULL; */
2980 kfree(mdev->int_dig_out);
2981 kfree(mdev->int_dig_in);
2982 kfree(mdev->int_dig_vv);
2984 /* cleanup the rest that has been
2985 * allocated from drbd_new_device
2986 * and actually free the mdev itself */
2987 drbd_free_mdev(mdev);
2990 static void drbd_cleanup(void)
2994 unregister_reboot_notifier(&drbd_notifier);
3000 remove_proc_entry("drbd", NULL);
3003 drbd_delete_device(i);
3004 drbd_destroy_mempools();
3009 unregister_blkdev(DRBD_MAJOR, "drbd");
3011 printk(KERN_INFO "drbd: module cleanup done.\n");
3015 * drbd_congested() - Callback for pdflush
3016 * @congested_data: User data
3017 * @bdi_bits: Bits pdflush is currently interested in
3019 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
3021 static int drbd_congested(void *congested_data, int bdi_bits)
3023 struct drbd_conf *mdev = congested_data;
3024 struct request_queue *q;
3028 if (!__inc_ap_bio_cond(mdev)) {
3029 /* DRBD has frozen IO */
3035 if (get_ldev(mdev)) {
3036 q = bdev_get_queue(mdev->ldev->backing_bdev);
3037 r = bdi_congested(&q->backing_dev_info, bdi_bits);
3043 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) {
3044 r |= (1 << BDI_async_congested);
3045 reason = reason == 'b' ? 'a' : 'n';
3049 mdev->congestion_reason = reason;
3053 struct drbd_conf *drbd_new_device(unsigned int minor)
3055 struct drbd_conf *mdev;
3056 struct gendisk *disk;
3057 struct request_queue *q;
3059 /* GFP_KERNEL, we are outside of all write-out paths */
3060 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
3063 if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL))
3064 goto out_no_cpumask;
3066 mdev->minor = minor;
3068 drbd_init_set_defaults(mdev);
3070 q = blk_alloc_queue(GFP_KERNEL);
3074 q->queuedata = mdev;
3076 disk = alloc_disk(1);
3081 set_disk_ro(disk, TRUE);
3084 disk->major = DRBD_MAJOR;
3085 disk->first_minor = minor;
3086 disk->fops = &drbd_ops;
3087 sprintf(disk->disk_name, "drbd%d", minor);
3088 disk->private_data = mdev;
3090 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
3091 /* we have no partitions. we contain only ourselves. */
3092 mdev->this_bdev->bd_contains = mdev->this_bdev;
3094 q->backing_dev_info.congested_fn = drbd_congested;
3095 q->backing_dev_info.congested_data = mdev;
3097 blk_queue_make_request(q, drbd_make_request_26);
3098 blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE);
3099 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
3100 blk_queue_merge_bvec(q, drbd_merge_bvec);
3101 q->queue_lock = &mdev->req_lock; /* needed since we use */
3102 /* plugging on a queue, that actually has no requests! */
3103 q->unplug_fn = drbd_unplug_fn;
3105 mdev->md_io_page = alloc_page(GFP_KERNEL);
3106 if (!mdev->md_io_page)
3107 goto out_no_io_page;
3109 if (drbd_bm_init(mdev))
3111 /* no need to lock access, we are still initializing this minor device. */
3115 mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL);
3116 if (!mdev->app_reads_hash)
3117 goto out_no_app_reads;
3119 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
3120 if (!mdev->current_epoch)
3123 INIT_LIST_HEAD(&mdev->current_epoch->list);
3128 /* out_whatever_else:
3129 kfree(mdev->current_epoch); */
3131 kfree(mdev->app_reads_hash);
3135 drbd_bm_cleanup(mdev);
3137 __free_page(mdev->md_io_page);
3141 blk_cleanup_queue(q);
3143 free_cpumask_var(mdev->cpu_mask);
3149 /* counterpart of drbd_new_device.
3150 * last part of drbd_delete_device. */
3151 void drbd_free_mdev(struct drbd_conf *mdev)
3153 kfree(mdev->current_epoch);
3154 kfree(mdev->app_reads_hash);
3156 if (mdev->bitmap) /* should no longer be there. */
3157 drbd_bm_cleanup(mdev);
3158 __free_page(mdev->md_io_page);
3159 put_disk(mdev->vdisk);
3160 blk_cleanup_queue(mdev->rq_queue);
3161 free_cpumask_var(mdev->cpu_mask);
3166 int __init drbd_init(void)
3170 if (sizeof(struct p_handshake) != 80) {
3172 "drbd: never change the size or layout "
3173 "of the HandShake packet.\n");
3177 if (1 > minor_count || minor_count > 255) {
3179 "drbd: invalid minor_count (%d)\n", minor_count);
3187 err = drbd_nl_init();
3191 err = register_blkdev(DRBD_MAJOR, "drbd");
3194 "drbd: unable to register block device major %d\n",
3199 register_reboot_notifier(&drbd_notifier);
3202 * allocate all necessary structs
3206 init_waitqueue_head(&drbd_pp_wait);
3208 drbd_proc = NULL; /* play safe for drbd_cleanup */
3209 minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
3214 err = drbd_create_mempools();
3218 drbd_proc = proc_create_data("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops, NULL);
3220 printk(KERN_ERR "drbd: unable to register proc file\n");
3224 rwlock_init(&global_state_lock);
3226 printk(KERN_INFO "drbd: initialized. "
3227 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
3228 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
3229 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
3230 printk(KERN_INFO "drbd: registered as block device major %d\n",
3232 printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
3234 return 0; /* Success! */
3239 /* currently always the case */
3240 printk(KERN_ERR "drbd: ran out of memory\n");
3242 printk(KERN_ERR "drbd: initialization failure\n");
3246 void drbd_free_bc(struct drbd_backing_dev *ldev)
3251 bd_release(ldev->backing_bdev);
3252 bd_release(ldev->md_bdev);
3254 fput(ldev->lo_file);
3255 fput(ldev->md_file);
3260 void drbd_free_sock(struct drbd_conf *mdev)
3262 if (mdev->data.socket) {
3263 mutex_lock(&mdev->data.mutex);
3264 kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR);
3265 sock_release(mdev->data.socket);
3266 mdev->data.socket = NULL;
3267 mutex_unlock(&mdev->data.mutex);
3269 if (mdev->meta.socket) {
3270 mutex_lock(&mdev->meta.mutex);
3271 kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR);
3272 sock_release(mdev->meta.socket);
3273 mdev->meta.socket = NULL;
3274 mutex_unlock(&mdev->meta.mutex);
3279 void drbd_free_resources(struct drbd_conf *mdev)
3281 crypto_free_hash(mdev->csums_tfm);
3282 mdev->csums_tfm = NULL;
3283 crypto_free_hash(mdev->verify_tfm);
3284 mdev->verify_tfm = NULL;
3285 crypto_free_hash(mdev->cram_hmac_tfm);
3286 mdev->cram_hmac_tfm = NULL;
3287 crypto_free_hash(mdev->integrity_w_tfm);
3288 mdev->integrity_w_tfm = NULL;
3289 crypto_free_hash(mdev->integrity_r_tfm);
3290 mdev->integrity_r_tfm = NULL;
3292 drbd_free_sock(mdev);
3295 drbd_free_bc(mdev->ldev);
3296 mdev->ldev = NULL;);
3299 /* meta data management */
3301 struct meta_data_on_disk {
3302 u64 la_size; /* last agreed size. */
3303 u64 uuid[UI_SIZE]; /* UUIDs. */
3306 u32 flags; /* MDF */
3309 u32 al_offset; /* offset to this block */
3310 u32 al_nr_extents; /* important for restoring the AL */
3311 /* `-- act_log->nr_elements <-- sync_conf.al_extents */
3312 u32 bm_offset; /* offset to the bitmap, from here */
3313 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
3314 u32 reserved_u32[4];
3319 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
3320 * @mdev: DRBD device.
3322 void drbd_md_sync(struct drbd_conf *mdev)
3324 struct meta_data_on_disk *buffer;
3328 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
3330 del_timer(&mdev->md_sync_timer);
3332 /* We use here D_FAILED and not D_ATTACHING because we try to write
3333 * metadata even if we detach due to a disk failure! */
3334 if (!get_ldev_if_state(mdev, D_FAILED))
3337 mutex_lock(&mdev->md_io_mutex);
3338 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3339 memset(buffer, 0, 512);
3341 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
3342 for (i = UI_CURRENT; i < UI_SIZE; i++)
3343 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
3344 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
3345 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
3347 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
3348 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
3349 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
3350 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
3351 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
3353 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
3355 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
3356 sector = mdev->ldev->md.md_offset;
3358 if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
3359 clear_bit(MD_DIRTY, &mdev->flags);
3361 /* this was a try anyways ... */
3362 dev_err(DEV, "meta data update failed!\n");
3364 drbd_chk_io_error(mdev, 1, TRUE);
3367 /* Update mdev->ldev->md.la_size_sect,
3368 * since we updated it on metadata. */
3369 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
3371 mutex_unlock(&mdev->md_io_mutex);
3376 * drbd_md_read() - Reads in the meta data super block
3377 * @mdev: DRBD device.
3378 * @bdev: Device from which the meta data should be read in.
3380 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_codes in case
3381 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
3383 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
3385 struct meta_data_on_disk *buffer;
3386 int i, rv = NO_ERROR;
3388 if (!get_ldev_if_state(mdev, D_ATTACHING))
3389 return ERR_IO_MD_DISK;
3391 mutex_lock(&mdev->md_io_mutex);
3392 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3394 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
3395 /* NOTE: cant do normal error processing here as this is
3396 called BEFORE disk is attached */
3397 dev_err(DEV, "Error while reading metadata.\n");
3398 rv = ERR_IO_MD_DISK;
3402 if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) {
3403 dev_err(DEV, "Error while reading metadata, magic not found.\n");
3404 rv = ERR_MD_INVALID;
3407 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
3408 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
3409 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
3410 rv = ERR_MD_INVALID;
3413 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
3414 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
3415 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
3416 rv = ERR_MD_INVALID;
3419 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
3420 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
3421 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
3422 rv = ERR_MD_INVALID;
3426 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
3427 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
3428 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
3429 rv = ERR_MD_INVALID;
3433 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
3434 for (i = UI_CURRENT; i < UI_SIZE; i++)
3435 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
3436 bdev->md.flags = be32_to_cpu(buffer->flags);
3437 mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents);
3438 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
3440 if (mdev->sync_conf.al_extents < 7)
3441 mdev->sync_conf.al_extents = 127;
3444 mutex_unlock(&mdev->md_io_mutex);
3451 * drbd_md_mark_dirty() - Mark meta data super block as dirty
3452 * @mdev: DRBD device.
3454 * Call this function if you change anything that should be written to
3455 * the meta-data super block. This function sets MD_DIRTY, and starts a
3456 * timer that ensures that within five seconds you have to call drbd_md_sync().
3458 void drbd_md_mark_dirty(struct drbd_conf *mdev)
3460 set_bit(MD_DIRTY, &mdev->flags);
3461 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
3465 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
3469 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
3470 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
3473 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3475 if (idx == UI_CURRENT) {
3476 if (mdev->state.role == R_PRIMARY)
3481 drbd_set_ed_uuid(mdev, val);
3484 mdev->ldev->md.uuid[idx] = val;
3485 drbd_md_mark_dirty(mdev);
3489 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3491 if (mdev->ldev->md.uuid[idx]) {
3492 drbd_uuid_move_history(mdev);
3493 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
3495 _drbd_uuid_set(mdev, idx, val);
3499 * drbd_uuid_new_current() - Creates a new current UUID
3500 * @mdev: DRBD device.
3502 * Creates a new current UUID, and rotates the old current UUID into
3503 * the bitmap slot. Causes an incremental resync upon next connect.
3505 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
3509 dev_info(DEV, "Creating new current UUID\n");
3510 D_ASSERT(mdev->ldev->md.uuid[UI_BITMAP] == 0);
3511 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
3513 get_random_bytes(&val, sizeof(u64));
3514 _drbd_uuid_set(mdev, UI_CURRENT, val);
3517 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
3519 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
3523 drbd_uuid_move_history(mdev);
3524 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
3525 mdev->ldev->md.uuid[UI_BITMAP] = 0;
3527 if (mdev->ldev->md.uuid[UI_BITMAP])
3528 dev_warn(DEV, "bm UUID already set");
3530 mdev->ldev->md.uuid[UI_BITMAP] = val;
3531 mdev->ldev->md.uuid[UI_BITMAP] &= ~((u64)1);
3534 drbd_md_mark_dirty(mdev);
3538 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3539 * @mdev: DRBD device.
3541 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
3543 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
3547 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3548 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
3550 drbd_bm_set_all(mdev);
3552 rv = drbd_bm_write(mdev);
3555 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
3566 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3567 * @mdev: DRBD device.
3569 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
3571 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
3575 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3576 drbd_bm_clear_all(mdev);
3577 rv = drbd_bm_write(mdev);
3584 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3586 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
3589 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
3591 drbd_bm_lock(mdev, work->why);
3592 rv = work->io_fn(mdev);
3593 drbd_bm_unlock(mdev);
3595 clear_bit(BITMAP_IO, &mdev->flags);
3596 wake_up(&mdev->misc_wait);
3599 work->done(mdev, rv);
3601 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
3608 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
3609 * @mdev: DRBD device.
3610 * @io_fn: IO callback to be called when bitmap IO is possible
3611 * @done: callback to be called after the bitmap IO was performed
3612 * @why: Descriptive text of the reason for doing the IO
3614 * While IO on the bitmap happens we freeze application IO thus we ensure
3615 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
3616 * called from worker context. It MUST NOT be used while a previous such
3617 * work is still pending!
3619 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
3620 int (*io_fn)(struct drbd_conf *),
3621 void (*done)(struct drbd_conf *, int),
3624 D_ASSERT(current == mdev->worker.task);
3626 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
3627 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
3628 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
3629 if (mdev->bm_io_work.why)
3630 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
3631 why, mdev->bm_io_work.why);
3633 mdev->bm_io_work.io_fn = io_fn;
3634 mdev->bm_io_work.done = done;
3635 mdev->bm_io_work.why = why;
3637 set_bit(BITMAP_IO, &mdev->flags);
3638 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
3639 if (list_empty(&mdev->bm_io_work.w.list)) {
3640 set_bit(BITMAP_IO_QUEUED, &mdev->flags);
3641 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
3643 dev_err(DEV, "FIXME avoided double queuing bm_io_work\n");
3648 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
3649 * @mdev: DRBD device.
3650 * @io_fn: IO callback to be called when bitmap IO is possible
3651 * @why: Descriptive text of the reason for doing the IO
3653 * freezes application IO while that the actual IO operations runs. This
3654 * functions MAY NOT be called from worker context.
3656 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why)
3660 D_ASSERT(current != mdev->worker.task);
3662 drbd_suspend_io(mdev);
3664 drbd_bm_lock(mdev, why);
3666 drbd_bm_unlock(mdev);
3668 drbd_resume_io(mdev);
3673 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3675 if ((mdev->ldev->md.flags & flag) != flag) {
3676 drbd_md_mark_dirty(mdev);
3677 mdev->ldev->md.flags |= flag;
3681 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3683 if ((mdev->ldev->md.flags & flag) != 0) {
3684 drbd_md_mark_dirty(mdev);
3685 mdev->ldev->md.flags &= ~flag;
3688 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
3690 return (bdev->md.flags & flag) != 0;
3693 static void md_sync_timer_fn(unsigned long data)
3695 struct drbd_conf *mdev = (struct drbd_conf *) data;
3697 drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work);
3700 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3702 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3708 #ifdef CONFIG_DRBD_FAULT_INJECTION
3709 /* Fault insertion support including random number generator shamelessly
3710 * stolen from kernel/rcutorture.c */
3711 struct fault_random_state {
3712 unsigned long state;
3713 unsigned long count;
3716 #define FAULT_RANDOM_MULT 39916801 /* prime */
3717 #define FAULT_RANDOM_ADD 479001701 /* prime */
3718 #define FAULT_RANDOM_REFRESH 10000
3721 * Crude but fast random-number generator. Uses a linear congruential
3722 * generator, with occasional help from get_random_bytes().
3724 static unsigned long
3725 _drbd_fault_random(struct fault_random_state *rsp)
3729 if (!rsp->count--) {
3730 get_random_bytes(&refresh, sizeof(refresh));
3731 rsp->state += refresh;
3732 rsp->count = FAULT_RANDOM_REFRESH;
3734 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
3735 return swahw32(rsp->state);
3739 _drbd_fault_str(unsigned int type) {
3740 static char *_faults[] = {
3741 [DRBD_FAULT_MD_WR] = "Meta-data write",
3742 [DRBD_FAULT_MD_RD] = "Meta-data read",
3743 [DRBD_FAULT_RS_WR] = "Resync write",
3744 [DRBD_FAULT_RS_RD] = "Resync read",
3745 [DRBD_FAULT_DT_WR] = "Data write",
3746 [DRBD_FAULT_DT_RD] = "Data read",
3747 [DRBD_FAULT_DT_RA] = "Data read ahead",
3748 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
3749 [DRBD_FAULT_AL_EE] = "EE allocation",
3750 [DRBD_FAULT_RECEIVE] = "receive data corruption",
3753 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
3757 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
3759 static struct fault_random_state rrs = {0, 0};
3761 unsigned int ret = (
3763 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
3764 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
3769 if (printk_ratelimit())
3770 dev_warn(DEV, "***Simulating %s failure\n",
3771 _drbd_fault_str(type));
3778 const char *drbd_buildtag(void)
3780 /* DRBD built from external sources has here a reference to the
3781 git hash of the source code. */
3783 static char buildtag[38] = "\0uilt-in";
3785 if (buildtag[0] == 0) {
3786 #ifdef CONFIG_MODULES
3787 if (THIS_MODULE != NULL)
3788 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
3797 module_init(drbd_init)
3798 module_exit(drbd_cleanup)
3800 EXPORT_SYMBOL(drbd_conn_str);
3801 EXPORT_SYMBOL(drbd_role_str);
3802 EXPORT_SYMBOL(drbd_disk_str);
3803 EXPORT_SYMBOL(drbd_set_st_err_str);