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 if (get_ldev(mdev)) {
1217 if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) &&
1218 mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE &&
1219 !atomic_read(&mdev->new_c_uuid))
1220 atomic_set(&mdev->new_c_uuid, 2);
1225 if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) {
1226 /* Diskless peer becomes primary or got connected do diskless, primary peer. */
1227 if (ns.peer == R_PRIMARY && mdev->ldev->md.uuid[UI_BITMAP] == 0 &&
1228 !atomic_read(&mdev->new_c_uuid))
1229 atomic_set(&mdev->new_c_uuid, 2);
1231 /* D_DISKLESS Peer becomes secondary */
1232 if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
1233 drbd_al_to_on_disk_bm(mdev);
1237 /* Last part of the attaching process ... */
1238 if (ns.conn >= C_CONNECTED &&
1239 os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
1240 kfree(mdev->p_uuid); /* We expect to receive up-to-date UUIDs soon. */
1241 mdev->p_uuid = NULL; /* ...to not use the old ones in the mean time */
1242 drbd_send_sizes(mdev, 0, 0); /* to start sync... */
1243 drbd_send_uuids(mdev);
1244 drbd_send_state(mdev);
1247 /* We want to pause/continue resync, tell peer. */
1248 if (ns.conn >= C_CONNECTED &&
1249 ((os.aftr_isp != ns.aftr_isp) ||
1250 (os.user_isp != ns.user_isp)))
1251 drbd_send_state(mdev);
1253 /* In case one of the isp bits got set, suspend other devices. */
1254 if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
1255 (ns.aftr_isp || ns.peer_isp || ns.user_isp))
1256 suspend_other_sg(mdev);
1258 /* Make sure the peer gets informed about eventual state
1259 changes (ISP bits) while we were in WFReportParams. */
1260 if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
1261 drbd_send_state(mdev);
1263 /* We are in the progress to start a full sync... */
1264 if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
1265 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S))
1266 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, &abw_start_sync, "set_n_write from StartingSync");
1268 /* We are invalidating our self... */
1269 if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED &&
1270 os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT)
1271 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL, "set_n_write from invalidate");
1273 if (os.disk > D_FAILED && ns.disk == D_FAILED) {
1274 enum drbd_io_error_p eh;
1277 if (get_ldev_if_state(mdev, D_FAILED)) {
1278 eh = mdev->ldev->dc.on_io_error;
1282 drbd_rs_cancel_all(mdev);
1283 /* since get_ldev() only works as long as disk>=D_INCONSISTENT,
1284 and it is D_DISKLESS here, local_cnt can only go down, it can
1285 not increase... It will reach zero */
1286 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1288 mdev->rs_failed = 0;
1289 atomic_set(&mdev->rs_pending_cnt, 0);
1291 spin_lock_irq(&mdev->req_lock);
1292 _drbd_set_state(_NS(mdev, disk, D_DISKLESS), CS_HARD, NULL);
1293 spin_unlock_irq(&mdev->req_lock);
1295 if (eh == EP_CALL_HELPER)
1296 drbd_khelper(mdev, "local-io-error");
1299 if (os.disk > D_DISKLESS && ns.disk == D_DISKLESS) {
1301 if (os.disk == D_FAILED) /* && ns.disk == D_DISKLESS*/ {
1302 if (drbd_send_state(mdev))
1303 dev_warn(DEV, "Notified peer that my disk is broken.\n");
1305 dev_err(DEV, "Sending state in drbd_io_error() failed\n");
1308 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1309 lc_destroy(mdev->resync);
1310 mdev->resync = NULL;
1311 lc_destroy(mdev->act_log);
1312 mdev->act_log = NULL;
1314 drbd_free_bc(mdev->ldev);
1315 mdev->ldev = NULL;);
1317 if (mdev->md_io_tmpp)
1318 __free_page(mdev->md_io_tmpp);
1321 /* Disks got bigger while they were detached */
1322 if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
1323 test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) {
1324 if (ns.conn == C_CONNECTED)
1325 resync_after_online_grow(mdev);
1328 /* A resync finished or aborted, wake paused devices... */
1329 if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) ||
1330 (os.peer_isp && !ns.peer_isp) ||
1331 (os.user_isp && !ns.user_isp))
1332 resume_next_sg(mdev);
1334 /* Upon network connection, we need to start the receiver */
1335 if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED)
1336 drbd_thread_start(&mdev->receiver);
1338 /* Terminate worker thread if we are unconfigured - it will be
1339 restarted as needed... */
1340 if (ns.disk == D_DISKLESS &&
1341 ns.conn == C_STANDALONE &&
1342 ns.role == R_SECONDARY) {
1343 if (os.aftr_isp != ns.aftr_isp)
1344 resume_next_sg(mdev);
1345 /* set in __drbd_set_state, unless CONFIG_PENDING was set */
1346 if (test_bit(DEVICE_DYING, &mdev->flags))
1347 drbd_thread_stop_nowait(&mdev->worker);
1353 static int w_new_current_uuid(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1355 if (get_ldev(mdev)) {
1356 if (mdev->ldev->md.uuid[UI_BITMAP] == 0) {
1357 drbd_uuid_new_current(mdev);
1358 if (get_net_conf(mdev)) {
1359 drbd_send_uuids(mdev);
1366 atomic_dec(&mdev->new_c_uuid);
1367 wake_up(&mdev->misc_wait);
1372 static int drbd_thread_setup(void *arg)
1374 struct drbd_thread *thi = (struct drbd_thread *) arg;
1375 struct drbd_conf *mdev = thi->mdev;
1376 unsigned long flags;
1380 retval = thi->function(thi);
1382 spin_lock_irqsave(&thi->t_lock, flags);
1384 /* if the receiver has been "Exiting", the last thing it did
1385 * was set the conn state to "StandAlone",
1386 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
1387 * and receiver thread will be "started".
1388 * drbd_thread_start needs to set "Restarting" in that case.
1389 * t_state check and assignment needs to be within the same spinlock,
1390 * so either thread_start sees Exiting, and can remap to Restarting,
1391 * or thread_start see None, and can proceed as normal.
1394 if (thi->t_state == Restarting) {
1395 dev_info(DEV, "Restarting %s\n", current->comm);
1396 thi->t_state = Running;
1397 spin_unlock_irqrestore(&thi->t_lock, flags);
1402 thi->t_state = None;
1404 complete(&thi->stop);
1405 spin_unlock_irqrestore(&thi->t_lock, flags);
1407 dev_info(DEV, "Terminating %s\n", current->comm);
1409 /* Release mod reference taken when thread was started */
1410 module_put(THIS_MODULE);
1414 static void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi,
1415 int (*func) (struct drbd_thread *))
1417 spin_lock_init(&thi->t_lock);
1419 thi->t_state = None;
1420 thi->function = func;
1424 int drbd_thread_start(struct drbd_thread *thi)
1426 struct drbd_conf *mdev = thi->mdev;
1427 struct task_struct *nt;
1428 unsigned long flags;
1431 thi == &mdev->receiver ? "receiver" :
1432 thi == &mdev->asender ? "asender" :
1433 thi == &mdev->worker ? "worker" : "NONSENSE";
1435 /* is used from state engine doing drbd_thread_stop_nowait,
1436 * while holding the req lock irqsave */
1437 spin_lock_irqsave(&thi->t_lock, flags);
1439 switch (thi->t_state) {
1441 dev_info(DEV, "Starting %s thread (from %s [%d])\n",
1442 me, current->comm, current->pid);
1444 /* Get ref on module for thread - this is released when thread exits */
1445 if (!try_module_get(THIS_MODULE)) {
1446 dev_err(DEV, "Failed to get module reference in drbd_thread_start\n");
1447 spin_unlock_irqrestore(&thi->t_lock, flags);
1451 init_completion(&thi->stop);
1452 D_ASSERT(thi->task == NULL);
1453 thi->reset_cpu_mask = 1;
1454 thi->t_state = Running;
1455 spin_unlock_irqrestore(&thi->t_lock, flags);
1456 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
1458 nt = kthread_create(drbd_thread_setup, (void *) thi,
1459 "drbd%d_%s", mdev_to_minor(mdev), me);
1462 dev_err(DEV, "Couldn't start thread\n");
1464 module_put(THIS_MODULE);
1467 spin_lock_irqsave(&thi->t_lock, flags);
1469 thi->t_state = Running;
1470 spin_unlock_irqrestore(&thi->t_lock, flags);
1471 wake_up_process(nt);
1474 thi->t_state = Restarting;
1475 dev_info(DEV, "Restarting %s thread (from %s [%d])\n",
1476 me, current->comm, current->pid);
1481 spin_unlock_irqrestore(&thi->t_lock, flags);
1489 void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
1491 unsigned long flags;
1493 enum drbd_thread_state ns = restart ? Restarting : Exiting;
1495 /* may be called from state engine, holding the req lock irqsave */
1496 spin_lock_irqsave(&thi->t_lock, flags);
1498 if (thi->t_state == None) {
1499 spin_unlock_irqrestore(&thi->t_lock, flags);
1501 drbd_thread_start(thi);
1505 if (thi->t_state != ns) {
1506 if (thi->task == NULL) {
1507 spin_unlock_irqrestore(&thi->t_lock, flags);
1513 init_completion(&thi->stop);
1514 if (thi->task != current)
1515 force_sig(DRBD_SIGKILL, thi->task);
1519 spin_unlock_irqrestore(&thi->t_lock, flags);
1522 wait_for_completion(&thi->stop);
1527 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
1528 * @mdev: DRBD device.
1530 * Forces all threads of a device onto the same CPU. This is beneficial for
1531 * DRBD's performance. May be overwritten by user's configuration.
1533 void drbd_calc_cpu_mask(struct drbd_conf *mdev)
1537 /* user override. */
1538 if (cpumask_weight(mdev->cpu_mask))
1541 ord = mdev_to_minor(mdev) % cpumask_weight(cpu_online_mask);
1542 for_each_online_cpu(cpu) {
1544 cpumask_set_cpu(cpu, mdev->cpu_mask);
1548 /* should not be reached */
1549 cpumask_setall(mdev->cpu_mask);
1553 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
1554 * @mdev: DRBD device.
1556 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
1559 void drbd_thread_current_set_cpu(struct drbd_conf *mdev)
1561 struct task_struct *p = current;
1562 struct drbd_thread *thi =
1563 p == mdev->asender.task ? &mdev->asender :
1564 p == mdev->receiver.task ? &mdev->receiver :
1565 p == mdev->worker.task ? &mdev->worker :
1569 if (!thi->reset_cpu_mask)
1571 thi->reset_cpu_mask = 0;
1572 set_cpus_allowed_ptr(p, mdev->cpu_mask);
1576 /* the appropriate socket mutex must be held already */
1577 int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1578 enum drbd_packets cmd, struct p_header *h,
1579 size_t size, unsigned msg_flags)
1583 ERR_IF(!h) return FALSE;
1584 ERR_IF(!size) return FALSE;
1586 h->magic = BE_DRBD_MAGIC;
1587 h->command = cpu_to_be16(cmd);
1588 h->length = cpu_to_be16(size-sizeof(struct p_header));
1590 sent = drbd_send(mdev, sock, h, size, msg_flags);
1592 ok = (sent == size);
1594 dev_err(DEV, "short sent %s size=%d sent=%d\n",
1595 cmdname(cmd), (int)size, sent);
1599 /* don't pass the socket. we may only look at it
1600 * when we hold the appropriate socket mutex.
1602 int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1603 enum drbd_packets cmd, struct p_header *h, size_t size)
1606 struct socket *sock;
1608 if (use_data_socket) {
1609 mutex_lock(&mdev->data.mutex);
1610 sock = mdev->data.socket;
1612 mutex_lock(&mdev->meta.mutex);
1613 sock = mdev->meta.socket;
1616 /* drbd_disconnect() could have called drbd_free_sock()
1617 * while we were waiting in down()... */
1618 if (likely(sock != NULL))
1619 ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0);
1621 if (use_data_socket)
1622 mutex_unlock(&mdev->data.mutex);
1624 mutex_unlock(&mdev->meta.mutex);
1628 int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
1634 h.magic = BE_DRBD_MAGIC;
1635 h.command = cpu_to_be16(cmd);
1636 h.length = cpu_to_be16(size);
1638 if (!drbd_get_data_sock(mdev))
1642 drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0));
1644 drbd_send(mdev, mdev->data.socket, data, size, 0));
1646 drbd_put_data_sock(mdev);
1651 int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc)
1653 struct p_rs_param_89 *p;
1654 struct socket *sock;
1656 const int apv = mdev->agreed_pro_version;
1658 size = apv <= 87 ? sizeof(struct p_rs_param)
1659 : apv == 88 ? sizeof(struct p_rs_param)
1660 + strlen(mdev->sync_conf.verify_alg) + 1
1661 : /* 89 */ sizeof(struct p_rs_param_89);
1663 /* used from admin command context and receiver/worker context.
1664 * to avoid kmalloc, grab the socket right here,
1665 * then use the pre-allocated sbuf there */
1666 mutex_lock(&mdev->data.mutex);
1667 sock = mdev->data.socket;
1669 if (likely(sock != NULL)) {
1670 enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
1672 p = &mdev->data.sbuf.rs_param_89;
1674 /* initialize verify_alg and csums_alg */
1675 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
1677 p->rate = cpu_to_be32(sc->rate);
1680 strcpy(p->verify_alg, mdev->sync_conf.verify_alg);
1682 strcpy(p->csums_alg, mdev->sync_conf.csums_alg);
1684 rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
1686 rv = 0; /* not ok */
1688 mutex_unlock(&mdev->data.mutex);
1693 int drbd_send_protocol(struct drbd_conf *mdev)
1695 struct p_protocol *p;
1698 size = sizeof(struct p_protocol);
1700 if (mdev->agreed_pro_version >= 87)
1701 size += strlen(mdev->net_conf->integrity_alg) + 1;
1703 /* we must not recurse into our own queue,
1704 * as that is blocked during handshake */
1705 p = kmalloc(size, GFP_NOIO);
1709 p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol);
1710 p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p);
1711 p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p);
1712 p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p);
1713 p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries);
1716 if (mdev->net_conf->want_lose)
1718 if (mdev->net_conf->dry_run) {
1719 if (mdev->agreed_pro_version >= 92)
1722 dev_err(DEV, "--dry-run is not supported by peer");
1727 p->conn_flags = cpu_to_be32(cf);
1729 if (mdev->agreed_pro_version >= 87)
1730 strcpy(p->integrity_alg, mdev->net_conf->integrity_alg);
1732 rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL,
1733 (struct p_header *)p, size);
1738 int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
1743 if (!get_ldev_if_state(mdev, D_NEGOTIATING))
1746 for (i = UI_CURRENT; i < UI_SIZE; i++)
1747 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
1749 mdev->comm_bm_set = drbd_bm_total_weight(mdev);
1750 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
1751 uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
1752 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
1753 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
1754 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
1758 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS,
1759 (struct p_header *)&p, sizeof(p));
1762 int drbd_send_uuids(struct drbd_conf *mdev)
1764 return _drbd_send_uuids(mdev, 0);
1767 int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
1769 return _drbd_send_uuids(mdev, 8);
1773 int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val)
1777 p.uuid = cpu_to_be64(val);
1779 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID,
1780 (struct p_header *)&p, sizeof(p));
1783 int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags)
1786 sector_t d_size, u_size;
1790 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
1791 D_ASSERT(mdev->ldev->backing_bdev);
1792 d_size = drbd_get_max_capacity(mdev->ldev);
1793 u_size = mdev->ldev->dc.disk_size;
1794 q_order_type = drbd_queue_order_type(mdev);
1799 q_order_type = QUEUE_ORDERED_NONE;
1802 p.d_size = cpu_to_be64(d_size);
1803 p.u_size = cpu_to_be64(u_size);
1804 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
1805 p.max_segment_size = cpu_to_be32(queue_max_segment_size(mdev->rq_queue));
1806 p.queue_order_type = cpu_to_be16(q_order_type);
1807 p.dds_flags = cpu_to_be16(flags);
1809 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES,
1810 (struct p_header *)&p, sizeof(p));
1815 * drbd_send_state() - Sends the drbd state to the peer
1816 * @mdev: DRBD device.
1818 int drbd_send_state(struct drbd_conf *mdev)
1820 struct socket *sock;
1824 /* Grab state lock so we wont send state if we're in the middle
1825 * of a cluster wide state change on another thread */
1826 drbd_state_lock(mdev);
1828 mutex_lock(&mdev->data.mutex);
1830 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
1831 sock = mdev->data.socket;
1833 if (likely(sock != NULL)) {
1834 ok = _drbd_send_cmd(mdev, sock, P_STATE,
1835 (struct p_header *)&p, sizeof(p), 0);
1838 mutex_unlock(&mdev->data.mutex);
1840 drbd_state_unlock(mdev);
1844 int drbd_send_state_req(struct drbd_conf *mdev,
1845 union drbd_state mask, union drbd_state val)
1847 struct p_req_state p;
1849 p.mask = cpu_to_be32(mask.i);
1850 p.val = cpu_to_be32(val.i);
1852 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ,
1853 (struct p_header *)&p, sizeof(p));
1856 int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode)
1858 struct p_req_state_reply p;
1860 p.retcode = cpu_to_be32(retcode);
1862 return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY,
1863 (struct p_header *)&p, sizeof(p));
1866 int fill_bitmap_rle_bits(struct drbd_conf *mdev,
1867 struct p_compressed_bm *p,
1868 struct bm_xfer_ctx *c)
1870 struct bitstream bs;
1871 unsigned long plain_bits;
1878 /* may we use this feature? */
1879 if ((mdev->sync_conf.use_rle == 0) ||
1880 (mdev->agreed_pro_version < 90))
1883 if (c->bit_offset >= c->bm_bits)
1884 return 0; /* nothing to do. */
1886 /* use at most thus many bytes */
1887 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
1888 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
1889 /* plain bits covered in this code string */
1892 /* p->encoding & 0x80 stores whether the first run length is set.
1893 * bit offset is implicit.
1894 * start with toggle == 2 to be able to tell the first iteration */
1897 /* see how much plain bits we can stuff into one packet
1898 * using RLE and VLI. */
1900 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
1901 : _drbd_bm_find_next(mdev, c->bit_offset);
1904 rl = tmp - c->bit_offset;
1906 if (toggle == 2) { /* first iteration */
1908 /* the first checked bit was set,
1909 * store start value, */
1910 DCBP_set_start(p, 1);
1911 /* but skip encoding of zero run length */
1915 DCBP_set_start(p, 0);
1918 /* paranoia: catch zero runlength.
1919 * can only happen if bitmap is modified while we scan it. */
1921 dev_err(DEV, "unexpected zero runlength while encoding bitmap "
1922 "t:%u bo:%lu\n", toggle, c->bit_offset);
1926 bits = vli_encode_bits(&bs, rl);
1927 if (bits == -ENOBUFS) /* buffer full */
1930 dev_err(DEV, "error while encoding bitmap: %d\n", bits);
1936 c->bit_offset = tmp;
1937 } while (c->bit_offset < c->bm_bits);
1939 len = bs.cur.b - p->code + !!bs.cur.bit;
1941 if (plain_bits < (len << 3)) {
1942 /* incompressible with this method.
1943 * we need to rewind both word and bit position. */
1944 c->bit_offset -= plain_bits;
1945 bm_xfer_ctx_bit_to_word_offset(c);
1946 c->bit_offset = c->word_offset * BITS_PER_LONG;
1950 /* RLE + VLI was able to compress it just fine.
1951 * update c->word_offset. */
1952 bm_xfer_ctx_bit_to_word_offset(c);
1954 /* store pad_bits */
1955 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
1960 enum { OK, FAILED, DONE }
1961 send_bitmap_rle_or_plain(struct drbd_conf *mdev,
1962 struct p_header *h, struct bm_xfer_ctx *c)
1964 struct p_compressed_bm *p = (void*)h;
1965 unsigned long num_words;
1969 len = fill_bitmap_rle_bits(mdev, p, c);
1975 DCBP_set_code(p, RLE_VLI_Bits);
1976 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h,
1977 sizeof(*p) + len, 0);
1980 c->bytes[0] += sizeof(*p) + len;
1982 if (c->bit_offset >= c->bm_bits)
1985 /* was not compressible.
1986 * send a buffer full of plain text bits instead. */
1987 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
1988 len = num_words * sizeof(long);
1990 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
1991 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP,
1992 h, sizeof(struct p_header) + len, 0);
1993 c->word_offset += num_words;
1994 c->bit_offset = c->word_offset * BITS_PER_LONG;
1997 c->bytes[1] += sizeof(struct p_header) + len;
1999 if (c->bit_offset > c->bm_bits)
2000 c->bit_offset = c->bm_bits;
2002 ok = ok ? ((len == 0) ? DONE : OK) : FAILED;
2005 INFO_bm_xfer_stats(mdev, "send", c);
2009 /* See the comment at receive_bitmap() */
2010 int _drbd_send_bitmap(struct drbd_conf *mdev)
2012 struct bm_xfer_ctx c;
2016 ERR_IF(!mdev->bitmap) return FALSE;
2018 /* maybe we should use some per thread scratch page,
2019 * and allocate that during initial device creation? */
2020 p = (struct p_header *) __get_free_page(GFP_NOIO);
2022 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
2026 if (get_ldev(mdev)) {
2027 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
2028 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
2029 drbd_bm_set_all(mdev);
2030 if (drbd_bm_write(mdev)) {
2031 /* write_bm did fail! Leave full sync flag set in Meta P_DATA
2032 * but otherwise process as per normal - need to tell other
2033 * side that a full resync is required! */
2034 dev_err(DEV, "Failed to write bitmap to disk!\n");
2036 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2043 c = (struct bm_xfer_ctx) {
2044 .bm_bits = drbd_bm_bits(mdev),
2045 .bm_words = drbd_bm_words(mdev),
2049 ret = send_bitmap_rle_or_plain(mdev, p, &c);
2050 } while (ret == OK);
2052 free_page((unsigned long) p);
2053 return (ret == DONE);
2056 int drbd_send_bitmap(struct drbd_conf *mdev)
2060 if (!drbd_get_data_sock(mdev))
2062 err = !_drbd_send_bitmap(mdev);
2063 drbd_put_data_sock(mdev);
2067 int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
2070 struct p_barrier_ack p;
2072 p.barrier = barrier_nr;
2073 p.set_size = cpu_to_be32(set_size);
2075 if (mdev->state.conn < C_CONNECTED)
2077 ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK,
2078 (struct p_header *)&p, sizeof(p));
2083 * _drbd_send_ack() - Sends an ack packet
2084 * @mdev: DRBD device.
2085 * @cmd: Packet command code.
2086 * @sector: sector, needs to be in big endian byte order
2087 * @blksize: size in byte, needs to be in big endian byte order
2088 * @block_id: Id, big endian byte order
2090 static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
2096 struct p_block_ack p;
2099 p.block_id = block_id;
2100 p.blksize = blksize;
2101 p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq));
2103 if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED)
2105 ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd,
2106 (struct p_header *)&p, sizeof(p));
2110 int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
2113 const int header_size = sizeof(struct p_data)
2114 - sizeof(struct p_header);
2115 int data_size = ((struct p_header *)dp)->length - header_size;
2117 return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
2121 int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
2122 struct p_block_req *rp)
2124 return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
2128 * drbd_send_ack() - Sends an ack packet
2129 * @mdev: DRBD device.
2130 * @cmd: Packet command code.
2133 int drbd_send_ack(struct drbd_conf *mdev,
2134 enum drbd_packets cmd, struct drbd_epoch_entry *e)
2136 return _drbd_send_ack(mdev, cmd,
2137 cpu_to_be64(e->sector),
2138 cpu_to_be32(e->size),
2142 /* This function misuses the block_id field to signal if the blocks
2143 * are is sync or not. */
2144 int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
2145 sector_t sector, int blksize, u64 block_id)
2147 return _drbd_send_ack(mdev, cmd,
2148 cpu_to_be64(sector),
2149 cpu_to_be32(blksize),
2150 cpu_to_be64(block_id));
2153 int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
2154 sector_t sector, int size, u64 block_id)
2157 struct p_block_req p;
2159 p.sector = cpu_to_be64(sector);
2160 p.block_id = block_id;
2161 p.blksize = cpu_to_be32(size);
2163 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd,
2164 (struct p_header *)&p, sizeof(p));
2168 int drbd_send_drequest_csum(struct drbd_conf *mdev,
2169 sector_t sector, int size,
2170 void *digest, int digest_size,
2171 enum drbd_packets cmd)
2174 struct p_block_req p;
2176 p.sector = cpu_to_be64(sector);
2177 p.block_id = BE_DRBD_MAGIC + 0xbeef;
2178 p.blksize = cpu_to_be32(size);
2180 p.head.magic = BE_DRBD_MAGIC;
2181 p.head.command = cpu_to_be16(cmd);
2182 p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header) + digest_size);
2184 mutex_lock(&mdev->data.mutex);
2186 ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0));
2187 ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0));
2189 mutex_unlock(&mdev->data.mutex);
2194 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
2197 struct p_block_req p;
2199 p.sector = cpu_to_be64(sector);
2200 p.block_id = BE_DRBD_MAGIC + 0xbabe;
2201 p.blksize = cpu_to_be32(size);
2203 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST,
2204 (struct p_header *)&p, sizeof(p));
2208 static int drbd_send_delay_probe(struct drbd_conf *mdev, struct drbd_socket *ds)
2210 struct p_delay_probe dp;
2214 mutex_lock(&ds->mutex);
2215 if (likely(ds->socket)) {
2216 do_gettimeofday(&now);
2217 offset = now.tv_usec - mdev->dps_time.tv_usec +
2218 (now.tv_sec - mdev->dps_time.tv_sec) * 1000000;
2219 dp.seq_num = cpu_to_be32(mdev->delay_seq);
2220 dp.offset = cpu_to_be32(offset);
2222 ok = _drbd_send_cmd(mdev, ds->socket, P_DELAY_PROBE,
2223 (struct p_header *)&dp, sizeof(dp), 0);
2225 mutex_unlock(&ds->mutex);
2230 static int drbd_send_delay_probes(struct drbd_conf *mdev)
2235 do_gettimeofday(&mdev->dps_time);
2236 ok = drbd_send_delay_probe(mdev, &mdev->meta);
2237 ok = ok && drbd_send_delay_probe(mdev, &mdev->data);
2239 mdev->dp_volume_last = mdev->send_cnt;
2240 mod_timer(&mdev->delay_probe_timer, jiffies + mdev->sync_conf.dp_interval * HZ / 10);
2245 /* called on sndtimeo
2246 * returns FALSE if we should retry,
2247 * TRUE if we think connection is dead
2249 static int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock)
2252 /* long elapsed = (long)(jiffies - mdev->last_received); */
2254 drop_it = mdev->meta.socket == sock
2255 || !mdev->asender.task
2256 || get_t_state(&mdev->asender) != Running
2257 || mdev->state.conn < C_CONNECTED;
2262 drop_it = !--mdev->ko_count;
2264 dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
2265 current->comm, current->pid, mdev->ko_count);
2269 return drop_it; /* && (mdev->state == R_PRIMARY) */;
2272 /* The idea of sendpage seems to be to put some kind of reference
2273 * to the page into the skb, and to hand it over to the NIC. In
2274 * this process get_page() gets called.
2276 * As soon as the page was really sent over the network put_page()
2277 * gets called by some part of the network layer. [ NIC driver? ]
2279 * [ get_page() / put_page() increment/decrement the count. If count
2280 * reaches 0 the page will be freed. ]
2282 * This works nicely with pages from FSs.
2283 * But this means that in protocol A we might signal IO completion too early!
2285 * In order not to corrupt data during a resync we must make sure
2286 * that we do not reuse our own buffer pages (EEs) to early, therefore
2287 * we have the net_ee list.
2289 * XFS seems to have problems, still, it submits pages with page_count == 0!
2290 * As a workaround, we disable sendpage on pages
2291 * with page_count == 0 or PageSlab.
2293 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
2294 int offset, size_t size)
2296 int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, 0);
2299 mdev->send_cnt += size>>9;
2300 return sent == size;
2303 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
2304 int offset, size_t size)
2306 mm_segment_t oldfs = get_fs();
2310 /* e.g. XFS meta- & log-data is in slab pages, which have a
2311 * page_count of 0 and/or have PageSlab() set.
2312 * we cannot use send_page for those, as that does get_page();
2313 * put_page(); and would cause either a VM_BUG directly, or
2314 * __page_cache_release a page that would actually still be referenced
2315 * by someone, leading to some obscure delayed Oops somewhere else. */
2316 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
2317 return _drbd_no_send_page(mdev, page, offset, size);
2319 drbd_update_congested(mdev);
2322 sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page,
2325 if (sent == -EAGAIN) {
2326 if (we_should_drop_the_connection(mdev,
2333 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
2334 __func__, (int)size, len, sent);
2339 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
2341 clear_bit(NET_CONGESTED, &mdev->flags);
2345 mdev->send_cnt += size>>9;
2349 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
2351 struct bio_vec *bvec;
2353 __bio_for_each_segment(bvec, bio, i, 0) {
2354 if (!_drbd_no_send_page(mdev, bvec->bv_page,
2355 bvec->bv_offset, bvec->bv_len))
2361 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
2363 struct bio_vec *bvec;
2365 __bio_for_each_segment(bvec, bio, i, 0) {
2366 if (!_drbd_send_page(mdev, bvec->bv_page,
2367 bvec->bv_offset, bvec->bv_len))
2374 static int _drbd_send_zc_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e)
2376 struct page *page = e->pages;
2377 unsigned len = e->size;
2378 page_chain_for_each(page) {
2379 unsigned l = min_t(unsigned, len, PAGE_SIZE);
2380 if (!_drbd_send_page(mdev, page, 0, l))
2387 static void consider_delay_probes(struct drbd_conf *mdev)
2389 if (mdev->state.conn != C_SYNC_SOURCE || mdev->agreed_pro_version < 93)
2392 if (mdev->dp_volume_last + mdev->sync_conf.dp_volume * 2 < mdev->send_cnt)
2393 drbd_send_delay_probes(mdev);
2396 static int w_delay_probes(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
2398 if (!cancel && mdev->state.conn == C_SYNC_SOURCE)
2399 drbd_send_delay_probes(mdev);
2404 static void delay_probe_timer_fn(unsigned long data)
2406 struct drbd_conf *mdev = (struct drbd_conf *) data;
2408 if (list_empty(&mdev->delay_probe_work.list))
2409 drbd_queue_work(&mdev->data.work, &mdev->delay_probe_work);
2412 /* Used to send write requests
2413 * R_PRIMARY -> Peer (P_DATA)
2415 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
2419 unsigned int dp_flags = 0;
2423 if (!drbd_get_data_sock(mdev))
2426 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2427 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2429 p.head.magic = BE_DRBD_MAGIC;
2430 p.head.command = cpu_to_be16(P_DATA);
2432 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + req->size);
2434 p.sector = cpu_to_be64(req->sector);
2435 p.block_id = (unsigned long)req;
2436 p.seq_num = cpu_to_be32(req->seq_num =
2437 atomic_add_return(1, &mdev->packet_seq));
2440 /* NOTE: no need to check if barriers supported here as we would
2441 * not pass the test in make_request_common in that case
2443 if (bio_rw_flagged(req->master_bio, BIO_RW_BARRIER)) {
2444 dev_err(DEV, "ASSERT FAILED would have set DP_HARDBARRIER\n");
2445 /* dp_flags |= DP_HARDBARRIER; */
2447 if (bio_rw_flagged(req->master_bio, BIO_RW_SYNCIO))
2448 dp_flags |= DP_RW_SYNC;
2449 /* for now handle SYNCIO and UNPLUG
2450 * as if they still were one and the same flag */
2451 if (bio_rw_flagged(req->master_bio, BIO_RW_UNPLUG))
2452 dp_flags |= DP_RW_SYNC;
2453 if (mdev->state.conn >= C_SYNC_SOURCE &&
2454 mdev->state.conn <= C_PAUSED_SYNC_T)
2455 dp_flags |= DP_MAY_SET_IN_SYNC;
2457 p.dp_flags = cpu_to_be32(dp_flags);
2458 set_bit(UNPLUG_REMOTE, &mdev->flags);
2460 drbd_send(mdev, mdev->data.socket, &p, sizeof(p), MSG_MORE));
2462 dgb = mdev->int_dig_out;
2463 drbd_csum_bio(mdev, mdev->integrity_w_tfm, req->master_bio, dgb);
2464 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2467 if (mdev->net_conf->wire_protocol == DRBD_PROT_A)
2468 ok = _drbd_send_bio(mdev, req->master_bio);
2470 ok = _drbd_send_zc_bio(mdev, req->master_bio);
2473 drbd_put_data_sock(mdev);
2476 consider_delay_probes(mdev);
2481 /* answer packet, used to send data back for read requests:
2482 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
2483 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
2485 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
2486 struct drbd_epoch_entry *e)
2493 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2494 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2496 p.head.magic = BE_DRBD_MAGIC;
2497 p.head.command = cpu_to_be16(cmd);
2499 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + e->size);
2501 p.sector = cpu_to_be64(e->sector);
2502 p.block_id = e->block_id;
2503 /* p.seq_num = 0; No sequence numbers here.. */
2505 /* Only called by our kernel thread.
2506 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
2507 * in response to admin command or module unload.
2509 if (!drbd_get_data_sock(mdev))
2512 ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p,
2513 sizeof(p), MSG_MORE);
2515 dgb = mdev->int_dig_out;
2516 drbd_csum_ee(mdev, mdev->integrity_w_tfm, e, dgb);
2517 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2520 ok = _drbd_send_zc_ee(mdev, e);
2522 drbd_put_data_sock(mdev);
2525 consider_delay_probes(mdev);
2531 drbd_send distinguishes two cases:
2533 Packets sent via the data socket "sock"
2534 and packets sent via the meta data socket "msock"
2537 -----------------+-------------------------+------------------------------
2538 timeout conf.timeout / 2 conf.timeout / 2
2539 timeout action send a ping via msock Abort communication
2540 and close all sockets
2544 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
2546 int drbd_send(struct drbd_conf *mdev, struct socket *sock,
2547 void *buf, size_t size, unsigned msg_flags)
2556 /* THINK if (signal_pending) return ... ? */
2561 msg.msg_name = NULL;
2562 msg.msg_namelen = 0;
2563 msg.msg_control = NULL;
2564 msg.msg_controllen = 0;
2565 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
2567 if (sock == mdev->data.socket) {
2568 mdev->ko_count = mdev->net_conf->ko_count;
2569 drbd_update_congested(mdev);
2573 * tcp_sendmsg does _not_ use its size parameter at all ?
2575 * -EAGAIN on timeout, -EINTR on signal.
2578 * do we need to block DRBD_SIG if sock == &meta.socket ??
2579 * otherwise wake_asender() might interrupt some send_*Ack !
2581 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
2582 if (rv == -EAGAIN) {
2583 if (we_should_drop_the_connection(mdev, sock))
2590 flush_signals(current);
2598 } while (sent < size);
2600 if (sock == mdev->data.socket)
2601 clear_bit(NET_CONGESTED, &mdev->flags);
2604 if (rv != -EAGAIN) {
2605 dev_err(DEV, "%s_sendmsg returned %d\n",
2606 sock == mdev->meta.socket ? "msock" : "sock",
2608 drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE));
2610 drbd_force_state(mdev, NS(conn, C_TIMEOUT));
2616 static int drbd_open(struct block_device *bdev, fmode_t mode)
2618 struct drbd_conf *mdev = bdev->bd_disk->private_data;
2619 unsigned long flags;
2622 spin_lock_irqsave(&mdev->req_lock, flags);
2623 /* to have a stable mdev->state.role
2624 * and no race with updating open_cnt */
2626 if (mdev->state.role != R_PRIMARY) {
2627 if (mode & FMODE_WRITE)
2629 else if (!allow_oos)
2635 spin_unlock_irqrestore(&mdev->req_lock, flags);
2640 static int drbd_release(struct gendisk *gd, fmode_t mode)
2642 struct drbd_conf *mdev = gd->private_data;
2647 static void drbd_unplug_fn(struct request_queue *q)
2649 struct drbd_conf *mdev = q->queuedata;
2652 spin_lock_irq(q->queue_lock);
2654 spin_unlock_irq(q->queue_lock);
2656 /* only if connected */
2657 spin_lock_irq(&mdev->req_lock);
2658 if (mdev->state.pdsk >= D_INCONSISTENT && mdev->state.conn >= C_CONNECTED) {
2659 D_ASSERT(mdev->state.role == R_PRIMARY);
2660 if (test_and_clear_bit(UNPLUG_REMOTE, &mdev->flags)) {
2661 /* add to the data.work queue,
2662 * unless already queued.
2663 * XXX this might be a good addition to drbd_queue_work
2664 * anyways, to detect "double queuing" ... */
2665 if (list_empty(&mdev->unplug_work.list))
2666 drbd_queue_work(&mdev->data.work,
2667 &mdev->unplug_work);
2670 spin_unlock_irq(&mdev->req_lock);
2672 if (mdev->state.disk >= D_INCONSISTENT)
2676 static void drbd_set_defaults(struct drbd_conf *mdev)
2678 mdev->sync_conf.after = DRBD_AFTER_DEF;
2679 mdev->sync_conf.rate = DRBD_RATE_DEF;
2680 mdev->sync_conf.al_extents = DRBD_AL_EXTENTS_DEF;
2681 mdev->state = (union drbd_state) {
2682 { .role = R_SECONDARY,
2684 .conn = C_STANDALONE,
2691 void drbd_init_set_defaults(struct drbd_conf *mdev)
2693 /* the memset(,0,) did most of this.
2694 * note: only assignments, no allocation in here */
2696 drbd_set_defaults(mdev);
2698 /* for now, we do NOT yet support it,
2699 * even though we start some framework
2700 * to eventually support barriers */
2701 set_bit(NO_BARRIER_SUPP, &mdev->flags);
2703 atomic_set(&mdev->ap_bio_cnt, 0);
2704 atomic_set(&mdev->ap_pending_cnt, 0);
2705 atomic_set(&mdev->rs_pending_cnt, 0);
2706 atomic_set(&mdev->unacked_cnt, 0);
2707 atomic_set(&mdev->local_cnt, 0);
2708 atomic_set(&mdev->net_cnt, 0);
2709 atomic_set(&mdev->packet_seq, 0);
2710 atomic_set(&mdev->pp_in_use, 0);
2711 atomic_set(&mdev->new_c_uuid, 0);
2713 mutex_init(&mdev->md_io_mutex);
2714 mutex_init(&mdev->data.mutex);
2715 mutex_init(&mdev->meta.mutex);
2716 sema_init(&mdev->data.work.s, 0);
2717 sema_init(&mdev->meta.work.s, 0);
2718 mutex_init(&mdev->state_mutex);
2720 spin_lock_init(&mdev->data.work.q_lock);
2721 spin_lock_init(&mdev->meta.work.q_lock);
2723 spin_lock_init(&mdev->al_lock);
2724 spin_lock_init(&mdev->req_lock);
2725 spin_lock_init(&mdev->peer_seq_lock);
2726 spin_lock_init(&mdev->epoch_lock);
2728 INIT_LIST_HEAD(&mdev->active_ee);
2729 INIT_LIST_HEAD(&mdev->sync_ee);
2730 INIT_LIST_HEAD(&mdev->done_ee);
2731 INIT_LIST_HEAD(&mdev->read_ee);
2732 INIT_LIST_HEAD(&mdev->net_ee);
2733 INIT_LIST_HEAD(&mdev->resync_reads);
2734 INIT_LIST_HEAD(&mdev->data.work.q);
2735 INIT_LIST_HEAD(&mdev->meta.work.q);
2736 INIT_LIST_HEAD(&mdev->resync_work.list);
2737 INIT_LIST_HEAD(&mdev->unplug_work.list);
2738 INIT_LIST_HEAD(&mdev->md_sync_work.list);
2739 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
2740 INIT_LIST_HEAD(&mdev->delay_probes);
2741 INIT_LIST_HEAD(&mdev->delay_probe_work.list);
2742 INIT_LIST_HEAD(&mdev->uuid_work.list);
2744 mdev->resync_work.cb = w_resync_inactive;
2745 mdev->unplug_work.cb = w_send_write_hint;
2746 mdev->md_sync_work.cb = w_md_sync;
2747 mdev->bm_io_work.w.cb = w_bitmap_io;
2748 mdev->delay_probe_work.cb = w_delay_probes;
2749 mdev->uuid_work.cb = w_new_current_uuid;
2750 init_timer(&mdev->resync_timer);
2751 init_timer(&mdev->md_sync_timer);
2752 init_timer(&mdev->delay_probe_timer);
2753 mdev->resync_timer.function = resync_timer_fn;
2754 mdev->resync_timer.data = (unsigned long) mdev;
2755 mdev->md_sync_timer.function = md_sync_timer_fn;
2756 mdev->md_sync_timer.data = (unsigned long) mdev;
2757 mdev->delay_probe_timer.function = delay_probe_timer_fn;
2758 mdev->delay_probe_timer.data = (unsigned long) mdev;
2761 init_waitqueue_head(&mdev->misc_wait);
2762 init_waitqueue_head(&mdev->state_wait);
2763 init_waitqueue_head(&mdev->ee_wait);
2764 init_waitqueue_head(&mdev->al_wait);
2765 init_waitqueue_head(&mdev->seq_wait);
2767 drbd_thread_init(mdev, &mdev->receiver, drbdd_init);
2768 drbd_thread_init(mdev, &mdev->worker, drbd_worker);
2769 drbd_thread_init(mdev, &mdev->asender, drbd_asender);
2771 mdev->agreed_pro_version = PRO_VERSION_MAX;
2772 mdev->write_ordering = WO_bio_barrier;
2773 mdev->resync_wenr = LC_FREE;
2776 void drbd_mdev_cleanup(struct drbd_conf *mdev)
2778 if (mdev->receiver.t_state != None)
2779 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
2780 mdev->receiver.t_state);
2782 /* no need to lock it, I'm the only thread alive */
2783 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
2784 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
2795 mdev->rs_mark_left =
2796 mdev->rs_mark_time = 0;
2797 D_ASSERT(mdev->net_conf == NULL);
2799 drbd_set_my_capacity(mdev, 0);
2801 /* maybe never allocated. */
2802 drbd_bm_resize(mdev, 0, 1);
2803 drbd_bm_cleanup(mdev);
2806 drbd_free_resources(mdev);
2809 * currently we drbd_init_ee only on module load, so
2810 * we may do drbd_release_ee only on module unload!
2812 D_ASSERT(list_empty(&mdev->active_ee));
2813 D_ASSERT(list_empty(&mdev->sync_ee));
2814 D_ASSERT(list_empty(&mdev->done_ee));
2815 D_ASSERT(list_empty(&mdev->read_ee));
2816 D_ASSERT(list_empty(&mdev->net_ee));
2817 D_ASSERT(list_empty(&mdev->resync_reads));
2818 D_ASSERT(list_empty(&mdev->data.work.q));
2819 D_ASSERT(list_empty(&mdev->meta.work.q));
2820 D_ASSERT(list_empty(&mdev->resync_work.list));
2821 D_ASSERT(list_empty(&mdev->unplug_work.list));
2826 static void drbd_destroy_mempools(void)
2830 while (drbd_pp_pool) {
2831 page = drbd_pp_pool;
2832 drbd_pp_pool = (struct page *)page_private(page);
2837 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
2839 if (drbd_ee_mempool)
2840 mempool_destroy(drbd_ee_mempool);
2841 if (drbd_request_mempool)
2842 mempool_destroy(drbd_request_mempool);
2844 kmem_cache_destroy(drbd_ee_cache);
2845 if (drbd_request_cache)
2846 kmem_cache_destroy(drbd_request_cache);
2847 if (drbd_bm_ext_cache)
2848 kmem_cache_destroy(drbd_bm_ext_cache);
2849 if (drbd_al_ext_cache)
2850 kmem_cache_destroy(drbd_al_ext_cache);
2852 drbd_ee_mempool = NULL;
2853 drbd_request_mempool = NULL;
2854 drbd_ee_cache = NULL;
2855 drbd_request_cache = NULL;
2856 drbd_bm_ext_cache = NULL;
2857 drbd_al_ext_cache = NULL;
2862 static int drbd_create_mempools(void)
2865 const int number = (DRBD_MAX_SEGMENT_SIZE/PAGE_SIZE) * minor_count;
2868 /* prepare our caches and mempools */
2869 drbd_request_mempool = NULL;
2870 drbd_ee_cache = NULL;
2871 drbd_request_cache = NULL;
2872 drbd_bm_ext_cache = NULL;
2873 drbd_al_ext_cache = NULL;
2874 drbd_pp_pool = NULL;
2877 drbd_request_cache = kmem_cache_create(
2878 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
2879 if (drbd_request_cache == NULL)
2882 drbd_ee_cache = kmem_cache_create(
2883 "drbd_ee", sizeof(struct drbd_epoch_entry), 0, 0, NULL);
2884 if (drbd_ee_cache == NULL)
2887 drbd_bm_ext_cache = kmem_cache_create(
2888 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
2889 if (drbd_bm_ext_cache == NULL)
2892 drbd_al_ext_cache = kmem_cache_create(
2893 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
2894 if (drbd_al_ext_cache == NULL)
2898 drbd_request_mempool = mempool_create(number,
2899 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
2900 if (drbd_request_mempool == NULL)
2903 drbd_ee_mempool = mempool_create(number,
2904 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2905 if (drbd_request_mempool == NULL)
2908 /* drbd's page pool */
2909 spin_lock_init(&drbd_pp_lock);
2911 for (i = 0; i < number; i++) {
2912 page = alloc_page(GFP_HIGHUSER);
2915 set_page_private(page, (unsigned long)drbd_pp_pool);
2916 drbd_pp_pool = page;
2918 drbd_pp_vacant = number;
2923 drbd_destroy_mempools(); /* in case we allocated some */
2927 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
2930 /* just so we have it. you never know what interesting things we
2931 * might want to do here some day...
2937 static struct notifier_block drbd_notifier = {
2938 .notifier_call = drbd_notify_sys,
2941 static void drbd_release_ee_lists(struct drbd_conf *mdev)
2945 rr = drbd_release_ee(mdev, &mdev->active_ee);
2947 dev_err(DEV, "%d EEs in active list found!\n", rr);
2949 rr = drbd_release_ee(mdev, &mdev->sync_ee);
2951 dev_err(DEV, "%d EEs in sync list found!\n", rr);
2953 rr = drbd_release_ee(mdev, &mdev->read_ee);
2955 dev_err(DEV, "%d EEs in read list found!\n", rr);
2957 rr = drbd_release_ee(mdev, &mdev->done_ee);
2959 dev_err(DEV, "%d EEs in done list found!\n", rr);
2961 rr = drbd_release_ee(mdev, &mdev->net_ee);
2963 dev_err(DEV, "%d EEs in net list found!\n", rr);
2966 /* caution. no locking.
2967 * currently only used from module cleanup code. */
2968 static void drbd_delete_device(unsigned int minor)
2970 struct drbd_conf *mdev = minor_to_mdev(minor);
2975 /* paranoia asserts */
2976 if (mdev->open_cnt != 0)
2977 dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,
2978 __FILE__ , __LINE__);
2980 ERR_IF (!list_empty(&mdev->data.work.q)) {
2981 struct list_head *lp;
2982 list_for_each(lp, &mdev->data.work.q) {
2983 dev_err(DEV, "lp = %p\n", lp);
2986 /* end paranoia asserts */
2988 del_gendisk(mdev->vdisk);
2990 /* cleanup stuff that may have been allocated during
2991 * device (re-)configuration or state changes */
2993 if (mdev->this_bdev)
2994 bdput(mdev->this_bdev);
2996 drbd_free_resources(mdev);
2998 drbd_release_ee_lists(mdev);
3000 /* should be free'd on disconnect? */
3001 kfree(mdev->ee_hash);
3003 mdev->ee_hash_s = 0;
3004 mdev->ee_hash = NULL;
3007 lc_destroy(mdev->act_log);
3008 lc_destroy(mdev->resync);
3010 kfree(mdev->p_uuid);
3011 /* mdev->p_uuid = NULL; */
3013 kfree(mdev->int_dig_out);
3014 kfree(mdev->int_dig_in);
3015 kfree(mdev->int_dig_vv);
3017 /* cleanup the rest that has been
3018 * allocated from drbd_new_device
3019 * and actually free the mdev itself */
3020 drbd_free_mdev(mdev);
3023 static void drbd_cleanup(void)
3027 unregister_reboot_notifier(&drbd_notifier);
3033 remove_proc_entry("drbd", NULL);
3036 drbd_delete_device(i);
3037 drbd_destroy_mempools();
3042 unregister_blkdev(DRBD_MAJOR, "drbd");
3044 printk(KERN_INFO "drbd: module cleanup done.\n");
3048 * drbd_congested() - Callback for pdflush
3049 * @congested_data: User data
3050 * @bdi_bits: Bits pdflush is currently interested in
3052 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
3054 static int drbd_congested(void *congested_data, int bdi_bits)
3056 struct drbd_conf *mdev = congested_data;
3057 struct request_queue *q;
3061 if (!__inc_ap_bio_cond(mdev)) {
3062 /* DRBD has frozen IO */
3068 if (get_ldev(mdev)) {
3069 q = bdev_get_queue(mdev->ldev->backing_bdev);
3070 r = bdi_congested(&q->backing_dev_info, bdi_bits);
3076 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) {
3077 r |= (1 << BDI_async_congested);
3078 reason = reason == 'b' ? 'a' : 'n';
3082 mdev->congestion_reason = reason;
3086 struct drbd_conf *drbd_new_device(unsigned int minor)
3088 struct drbd_conf *mdev;
3089 struct gendisk *disk;
3090 struct request_queue *q;
3092 /* GFP_KERNEL, we are outside of all write-out paths */
3093 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
3096 if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL))
3097 goto out_no_cpumask;
3099 mdev->minor = minor;
3101 drbd_init_set_defaults(mdev);
3103 q = blk_alloc_queue(GFP_KERNEL);
3107 q->queuedata = mdev;
3109 disk = alloc_disk(1);
3114 set_disk_ro(disk, TRUE);
3117 disk->major = DRBD_MAJOR;
3118 disk->first_minor = minor;
3119 disk->fops = &drbd_ops;
3120 sprintf(disk->disk_name, "drbd%d", minor);
3121 disk->private_data = mdev;
3123 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
3124 /* we have no partitions. we contain only ourselves. */
3125 mdev->this_bdev->bd_contains = mdev->this_bdev;
3127 q->backing_dev_info.congested_fn = drbd_congested;
3128 q->backing_dev_info.congested_data = mdev;
3130 blk_queue_make_request(q, drbd_make_request_26);
3131 blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE);
3132 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
3133 blk_queue_merge_bvec(q, drbd_merge_bvec);
3134 q->queue_lock = &mdev->req_lock; /* needed since we use */
3135 /* plugging on a queue, that actually has no requests! */
3136 q->unplug_fn = drbd_unplug_fn;
3138 mdev->md_io_page = alloc_page(GFP_KERNEL);
3139 if (!mdev->md_io_page)
3140 goto out_no_io_page;
3142 if (drbd_bm_init(mdev))
3144 /* no need to lock access, we are still initializing this minor device. */
3148 mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL);
3149 if (!mdev->app_reads_hash)
3150 goto out_no_app_reads;
3152 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
3153 if (!mdev->current_epoch)
3156 INIT_LIST_HEAD(&mdev->current_epoch->list);
3161 /* out_whatever_else:
3162 kfree(mdev->current_epoch); */
3164 kfree(mdev->app_reads_hash);
3168 drbd_bm_cleanup(mdev);
3170 __free_page(mdev->md_io_page);
3174 blk_cleanup_queue(q);
3176 free_cpumask_var(mdev->cpu_mask);
3182 /* counterpart of drbd_new_device.
3183 * last part of drbd_delete_device. */
3184 void drbd_free_mdev(struct drbd_conf *mdev)
3186 kfree(mdev->current_epoch);
3187 kfree(mdev->app_reads_hash);
3189 if (mdev->bitmap) /* should no longer be there. */
3190 drbd_bm_cleanup(mdev);
3191 __free_page(mdev->md_io_page);
3192 put_disk(mdev->vdisk);
3193 blk_cleanup_queue(mdev->rq_queue);
3194 free_cpumask_var(mdev->cpu_mask);
3199 int __init drbd_init(void)
3203 if (sizeof(struct p_handshake) != 80) {
3205 "drbd: never change the size or layout "
3206 "of the HandShake packet.\n");
3210 if (1 > minor_count || minor_count > 255) {
3212 "drbd: invalid minor_count (%d)\n", minor_count);
3220 err = drbd_nl_init();
3224 err = register_blkdev(DRBD_MAJOR, "drbd");
3227 "drbd: unable to register block device major %d\n",
3232 register_reboot_notifier(&drbd_notifier);
3235 * allocate all necessary structs
3239 init_waitqueue_head(&drbd_pp_wait);
3241 drbd_proc = NULL; /* play safe for drbd_cleanup */
3242 minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
3247 err = drbd_create_mempools();
3251 drbd_proc = proc_create_data("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops, NULL);
3253 printk(KERN_ERR "drbd: unable to register proc file\n");
3257 rwlock_init(&global_state_lock);
3259 printk(KERN_INFO "drbd: initialized. "
3260 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
3261 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
3262 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
3263 printk(KERN_INFO "drbd: registered as block device major %d\n",
3265 printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
3267 return 0; /* Success! */
3272 /* currently always the case */
3273 printk(KERN_ERR "drbd: ran out of memory\n");
3275 printk(KERN_ERR "drbd: initialization failure\n");
3279 void drbd_free_bc(struct drbd_backing_dev *ldev)
3284 bd_release(ldev->backing_bdev);
3285 bd_release(ldev->md_bdev);
3287 fput(ldev->lo_file);
3288 fput(ldev->md_file);
3293 void drbd_free_sock(struct drbd_conf *mdev)
3295 if (mdev->data.socket) {
3296 mutex_lock(&mdev->data.mutex);
3297 kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR);
3298 sock_release(mdev->data.socket);
3299 mdev->data.socket = NULL;
3300 mutex_unlock(&mdev->data.mutex);
3302 if (mdev->meta.socket) {
3303 mutex_lock(&mdev->meta.mutex);
3304 kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR);
3305 sock_release(mdev->meta.socket);
3306 mdev->meta.socket = NULL;
3307 mutex_unlock(&mdev->meta.mutex);
3312 void drbd_free_resources(struct drbd_conf *mdev)
3314 crypto_free_hash(mdev->csums_tfm);
3315 mdev->csums_tfm = NULL;
3316 crypto_free_hash(mdev->verify_tfm);
3317 mdev->verify_tfm = NULL;
3318 crypto_free_hash(mdev->cram_hmac_tfm);
3319 mdev->cram_hmac_tfm = NULL;
3320 crypto_free_hash(mdev->integrity_w_tfm);
3321 mdev->integrity_w_tfm = NULL;
3322 crypto_free_hash(mdev->integrity_r_tfm);
3323 mdev->integrity_r_tfm = NULL;
3325 drbd_free_sock(mdev);
3328 drbd_free_bc(mdev->ldev);
3329 mdev->ldev = NULL;);
3332 /* meta data management */
3334 struct meta_data_on_disk {
3335 u64 la_size; /* last agreed size. */
3336 u64 uuid[UI_SIZE]; /* UUIDs. */
3339 u32 flags; /* MDF */
3342 u32 al_offset; /* offset to this block */
3343 u32 al_nr_extents; /* important for restoring the AL */
3344 /* `-- act_log->nr_elements <-- sync_conf.al_extents */
3345 u32 bm_offset; /* offset to the bitmap, from here */
3346 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
3347 u32 reserved_u32[4];
3352 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
3353 * @mdev: DRBD device.
3355 void drbd_md_sync(struct drbd_conf *mdev)
3357 struct meta_data_on_disk *buffer;
3361 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
3363 del_timer(&mdev->md_sync_timer);
3365 /* We use here D_FAILED and not D_ATTACHING because we try to write
3366 * metadata even if we detach due to a disk failure! */
3367 if (!get_ldev_if_state(mdev, D_FAILED))
3370 mutex_lock(&mdev->md_io_mutex);
3371 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3372 memset(buffer, 0, 512);
3374 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
3375 for (i = UI_CURRENT; i < UI_SIZE; i++)
3376 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
3377 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
3378 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
3380 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
3381 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
3382 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
3383 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
3384 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
3386 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
3388 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
3389 sector = mdev->ldev->md.md_offset;
3391 if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
3392 clear_bit(MD_DIRTY, &mdev->flags);
3394 /* this was a try anyways ... */
3395 dev_err(DEV, "meta data update failed!\n");
3397 drbd_chk_io_error(mdev, 1, TRUE);
3400 /* Update mdev->ldev->md.la_size_sect,
3401 * since we updated it on metadata. */
3402 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
3404 mutex_unlock(&mdev->md_io_mutex);
3409 * drbd_md_read() - Reads in the meta data super block
3410 * @mdev: DRBD device.
3411 * @bdev: Device from which the meta data should be read in.
3413 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_codes in case
3414 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
3416 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
3418 struct meta_data_on_disk *buffer;
3419 int i, rv = NO_ERROR;
3421 if (!get_ldev_if_state(mdev, D_ATTACHING))
3422 return ERR_IO_MD_DISK;
3424 mutex_lock(&mdev->md_io_mutex);
3425 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3427 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
3428 /* NOTE: cant do normal error processing here as this is
3429 called BEFORE disk is attached */
3430 dev_err(DEV, "Error while reading metadata.\n");
3431 rv = ERR_IO_MD_DISK;
3435 if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) {
3436 dev_err(DEV, "Error while reading metadata, magic not found.\n");
3437 rv = ERR_MD_INVALID;
3440 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
3441 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
3442 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
3443 rv = ERR_MD_INVALID;
3446 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
3447 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
3448 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
3449 rv = ERR_MD_INVALID;
3452 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
3453 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
3454 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
3455 rv = ERR_MD_INVALID;
3459 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
3460 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
3461 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
3462 rv = ERR_MD_INVALID;
3466 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
3467 for (i = UI_CURRENT; i < UI_SIZE; i++)
3468 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
3469 bdev->md.flags = be32_to_cpu(buffer->flags);
3470 mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents);
3471 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
3473 if (mdev->sync_conf.al_extents < 7)
3474 mdev->sync_conf.al_extents = 127;
3477 mutex_unlock(&mdev->md_io_mutex);
3484 * drbd_md_mark_dirty() - Mark meta data super block as dirty
3485 * @mdev: DRBD device.
3487 * Call this function if you change anything that should be written to
3488 * the meta-data super block. This function sets MD_DIRTY, and starts a
3489 * timer that ensures that within five seconds you have to call drbd_md_sync().
3491 void drbd_md_mark_dirty(struct drbd_conf *mdev)
3493 set_bit(MD_DIRTY, &mdev->flags);
3494 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
3498 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
3502 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
3503 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
3506 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3508 if (idx == UI_CURRENT) {
3509 if (mdev->state.role == R_PRIMARY)
3514 drbd_set_ed_uuid(mdev, val);
3517 mdev->ldev->md.uuid[idx] = val;
3518 drbd_md_mark_dirty(mdev);
3522 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3524 if (mdev->ldev->md.uuid[idx]) {
3525 drbd_uuid_move_history(mdev);
3526 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
3528 _drbd_uuid_set(mdev, idx, val);
3532 * drbd_uuid_new_current() - Creates a new current UUID
3533 * @mdev: DRBD device.
3535 * Creates a new current UUID, and rotates the old current UUID into
3536 * the bitmap slot. Causes an incremental resync upon next connect.
3538 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
3542 dev_info(DEV, "Creating new current UUID\n");
3543 D_ASSERT(mdev->ldev->md.uuid[UI_BITMAP] == 0);
3544 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
3546 get_random_bytes(&val, sizeof(u64));
3547 _drbd_uuid_set(mdev, UI_CURRENT, val);
3550 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
3552 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
3556 drbd_uuid_move_history(mdev);
3557 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
3558 mdev->ldev->md.uuid[UI_BITMAP] = 0;
3560 if (mdev->ldev->md.uuid[UI_BITMAP])
3561 dev_warn(DEV, "bm UUID already set");
3563 mdev->ldev->md.uuid[UI_BITMAP] = val;
3564 mdev->ldev->md.uuid[UI_BITMAP] &= ~((u64)1);
3567 drbd_md_mark_dirty(mdev);
3571 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3572 * @mdev: DRBD device.
3574 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
3576 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
3580 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3581 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
3583 drbd_bm_set_all(mdev);
3585 rv = drbd_bm_write(mdev);
3588 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
3599 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3600 * @mdev: DRBD device.
3602 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
3604 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
3608 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3609 drbd_bm_clear_all(mdev);
3610 rv = drbd_bm_write(mdev);
3617 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3619 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
3622 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
3624 drbd_bm_lock(mdev, work->why);
3625 rv = work->io_fn(mdev);
3626 drbd_bm_unlock(mdev);
3628 clear_bit(BITMAP_IO, &mdev->flags);
3629 wake_up(&mdev->misc_wait);
3632 work->done(mdev, rv);
3634 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
3641 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
3642 * @mdev: DRBD device.
3643 * @io_fn: IO callback to be called when bitmap IO is possible
3644 * @done: callback to be called after the bitmap IO was performed
3645 * @why: Descriptive text of the reason for doing the IO
3647 * While IO on the bitmap happens we freeze application IO thus we ensure
3648 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
3649 * called from worker context. It MUST NOT be used while a previous such
3650 * work is still pending!
3652 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
3653 int (*io_fn)(struct drbd_conf *),
3654 void (*done)(struct drbd_conf *, int),
3657 D_ASSERT(current == mdev->worker.task);
3659 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
3660 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
3661 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
3662 if (mdev->bm_io_work.why)
3663 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
3664 why, mdev->bm_io_work.why);
3666 mdev->bm_io_work.io_fn = io_fn;
3667 mdev->bm_io_work.done = done;
3668 mdev->bm_io_work.why = why;
3670 set_bit(BITMAP_IO, &mdev->flags);
3671 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
3672 if (list_empty(&mdev->bm_io_work.w.list)) {
3673 set_bit(BITMAP_IO_QUEUED, &mdev->flags);
3674 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
3676 dev_err(DEV, "FIXME avoided double queuing bm_io_work\n");
3681 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
3682 * @mdev: DRBD device.
3683 * @io_fn: IO callback to be called when bitmap IO is possible
3684 * @why: Descriptive text of the reason for doing the IO
3686 * freezes application IO while that the actual IO operations runs. This
3687 * functions MAY NOT be called from worker context.
3689 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why)
3693 D_ASSERT(current != mdev->worker.task);
3695 drbd_suspend_io(mdev);
3697 drbd_bm_lock(mdev, why);
3699 drbd_bm_unlock(mdev);
3701 drbd_resume_io(mdev);
3706 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3708 if ((mdev->ldev->md.flags & flag) != flag) {
3709 drbd_md_mark_dirty(mdev);
3710 mdev->ldev->md.flags |= flag;
3714 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3716 if ((mdev->ldev->md.flags & flag) != 0) {
3717 drbd_md_mark_dirty(mdev);
3718 mdev->ldev->md.flags &= ~flag;
3721 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
3723 return (bdev->md.flags & flag) != 0;
3726 static void md_sync_timer_fn(unsigned long data)
3728 struct drbd_conf *mdev = (struct drbd_conf *) data;
3730 drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work);
3733 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3735 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3741 #ifdef CONFIG_DRBD_FAULT_INJECTION
3742 /* Fault insertion support including random number generator shamelessly
3743 * stolen from kernel/rcutorture.c */
3744 struct fault_random_state {
3745 unsigned long state;
3746 unsigned long count;
3749 #define FAULT_RANDOM_MULT 39916801 /* prime */
3750 #define FAULT_RANDOM_ADD 479001701 /* prime */
3751 #define FAULT_RANDOM_REFRESH 10000
3754 * Crude but fast random-number generator. Uses a linear congruential
3755 * generator, with occasional help from get_random_bytes().
3757 static unsigned long
3758 _drbd_fault_random(struct fault_random_state *rsp)
3762 if (!rsp->count--) {
3763 get_random_bytes(&refresh, sizeof(refresh));
3764 rsp->state += refresh;
3765 rsp->count = FAULT_RANDOM_REFRESH;
3767 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
3768 return swahw32(rsp->state);
3772 _drbd_fault_str(unsigned int type) {
3773 static char *_faults[] = {
3774 [DRBD_FAULT_MD_WR] = "Meta-data write",
3775 [DRBD_FAULT_MD_RD] = "Meta-data read",
3776 [DRBD_FAULT_RS_WR] = "Resync write",
3777 [DRBD_FAULT_RS_RD] = "Resync read",
3778 [DRBD_FAULT_DT_WR] = "Data write",
3779 [DRBD_FAULT_DT_RD] = "Data read",
3780 [DRBD_FAULT_DT_RA] = "Data read ahead",
3781 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
3782 [DRBD_FAULT_AL_EE] = "EE allocation",
3783 [DRBD_FAULT_RECEIVE] = "receive data corruption",
3786 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
3790 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
3792 static struct fault_random_state rrs = {0, 0};
3794 unsigned int ret = (
3796 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
3797 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
3802 if (printk_ratelimit())
3803 dev_warn(DEV, "***Simulating %s failure\n",
3804 _drbd_fault_str(type));
3811 const char *drbd_buildtag(void)
3813 /* DRBD built from external sources has here a reference to the
3814 git hash of the source code. */
3816 static char buildtag[38] = "\0uilt-in";
3818 if (buildtag[0] == 0) {
3819 #ifdef CONFIG_MODULES
3820 if (THIS_MODULE != NULL)
3821 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
3830 module_init(drbd_init)
3831 module_exit(drbd_cleanup)
3833 EXPORT_SYMBOL(drbd_conn_str);
3834 EXPORT_SYMBOL(drbd_role_str);
3835 EXPORT_SYMBOL(drbd_disk_str);
3836 EXPORT_SYMBOL(drbd_set_st_err_str);