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 ||
688 ns.conn == C_WF_BITMAP_S ||
689 ns.conn == C_SYNC_SOURCE ||
690 ns.conn == C_PAUSED_SYNC_S) &&
691 ns.disk == D_OUTDATED)
692 rv = SS_CONNECTED_OUTDATES;
694 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
695 (mdev->sync_conf.verify_alg[0] == 0))
696 rv = SS_NO_VERIFY_ALG;
698 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
699 mdev->agreed_pro_version < 88)
700 rv = SS_NOT_SUPPORTED;
706 * is_valid_state_transition() - Returns an SS_ error code if the state transition is not possible
707 * @mdev: DRBD device.
711 static int is_valid_state_transition(struct drbd_conf *mdev,
712 union drbd_state ns, union drbd_state os)
716 if ((ns.conn == C_STARTING_SYNC_T || ns.conn == C_STARTING_SYNC_S) &&
717 os.conn > C_CONNECTED)
718 rv = SS_RESYNC_RUNNING;
720 if (ns.conn == C_DISCONNECTING && os.conn == C_STANDALONE)
721 rv = SS_ALREADY_STANDALONE;
723 if (ns.disk > D_ATTACHING && os.disk == D_DISKLESS)
726 if (ns.conn == C_WF_CONNECTION && os.conn < C_UNCONNECTED)
727 rv = SS_NO_NET_CONFIG;
729 if (ns.disk == D_OUTDATED && os.disk < D_OUTDATED && os.disk != D_ATTACHING)
730 rv = SS_LOWER_THAN_OUTDATED;
732 if (ns.conn == C_DISCONNECTING && os.conn == C_UNCONNECTED)
733 rv = SS_IN_TRANSIENT_STATE;
735 if (ns.conn == os.conn && ns.conn == C_WF_REPORT_PARAMS)
736 rv = SS_IN_TRANSIENT_STATE;
738 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && os.conn < C_CONNECTED)
739 rv = SS_NEED_CONNECTION;
741 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
742 ns.conn != os.conn && os.conn > C_CONNECTED)
743 rv = SS_RESYNC_RUNNING;
745 if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) &&
746 os.conn < C_CONNECTED)
747 rv = SS_NEED_CONNECTION;
753 * sanitize_state() - Resolves implicitly necessary additional changes to a state transition
754 * @mdev: DRBD device.
759 * When we loose connection, we have to set the state of the peers disk (pdsk)
760 * to D_UNKNOWN. This rule and many more along those lines are in this function.
762 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
763 union drbd_state ns, int *warn_sync_abort)
765 enum drbd_fencing_p fp;
768 if (get_ldev(mdev)) {
769 fp = mdev->ldev->dc.fencing;
773 /* Disallow Network errors to configure a device's network part */
774 if ((ns.conn >= C_TIMEOUT && ns.conn <= C_TEAR_DOWN) &&
775 os.conn <= C_DISCONNECTING)
778 /* After a network error (+C_TEAR_DOWN) only C_UNCONNECTED or C_DISCONNECTING can follow */
779 if (os.conn >= C_TIMEOUT && os.conn <= C_TEAR_DOWN &&
780 ns.conn != C_UNCONNECTED && ns.conn != C_DISCONNECTING)
783 /* After C_DISCONNECTING only C_STANDALONE may follow */
784 if (os.conn == C_DISCONNECTING && ns.conn != C_STANDALONE)
787 if (ns.conn < C_CONNECTED) {
790 if (ns.pdsk > D_UNKNOWN || ns.pdsk < D_INCONSISTENT)
794 /* Clear the aftr_isp when becoming unconfigured */
795 if (ns.conn == C_STANDALONE && ns.disk == D_DISKLESS && ns.role == R_SECONDARY)
798 if (ns.conn <= C_DISCONNECTING && ns.disk == D_DISKLESS)
801 /* Abort resync if a disk fails/detaches */
802 if (os.conn > C_CONNECTED && ns.conn > C_CONNECTED &&
803 (ns.disk <= D_FAILED || ns.pdsk <= D_FAILED)) {
805 *warn_sync_abort = 1;
806 ns.conn = C_CONNECTED;
809 if (ns.conn >= C_CONNECTED &&
810 ((ns.disk == D_CONSISTENT || ns.disk == D_OUTDATED) ||
811 (ns.disk == D_NEGOTIATING && ns.conn == C_WF_BITMAP_T))) {
814 case C_PAUSED_SYNC_T:
815 ns.disk = D_OUTDATED;
820 case C_PAUSED_SYNC_S:
821 ns.disk = D_UP_TO_DATE;
824 ns.disk = D_INCONSISTENT;
825 dev_warn(DEV, "Implicitly set disk state Inconsistent!\n");
828 if (os.disk == D_OUTDATED && ns.disk == D_UP_TO_DATE)
829 dev_warn(DEV, "Implicitly set disk from Outdated to UpToDate\n");
832 if (ns.conn >= C_CONNECTED &&
833 (ns.pdsk == D_CONSISTENT || ns.pdsk == D_OUTDATED)) {
837 case C_PAUSED_SYNC_T:
839 ns.pdsk = D_UP_TO_DATE;
842 case C_PAUSED_SYNC_S:
843 ns.pdsk = D_OUTDATED;
846 ns.pdsk = D_INCONSISTENT;
847 dev_warn(DEV, "Implicitly set pdsk Inconsistent!\n");
850 if (os.pdsk == D_OUTDATED && ns.pdsk == D_UP_TO_DATE)
851 dev_warn(DEV, "Implicitly set pdsk from Outdated to UpToDate\n");
854 /* Connection breaks down before we finished "Negotiating" */
855 if (ns.conn < C_CONNECTED && ns.disk == D_NEGOTIATING &&
856 get_ldev_if_state(mdev, D_NEGOTIATING)) {
857 if (mdev->ed_uuid == mdev->ldev->md.uuid[UI_CURRENT]) {
858 ns.disk = mdev->new_state_tmp.disk;
859 ns.pdsk = mdev->new_state_tmp.pdsk;
861 dev_alert(DEV, "Connection lost while negotiating, no data!\n");
862 ns.disk = D_DISKLESS;
868 if (fp == FP_STONITH &&
869 (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk > D_OUTDATED) &&
870 !(os.role == R_PRIMARY && os.conn < C_CONNECTED && os.pdsk > D_OUTDATED))
873 if (ns.aftr_isp || ns.peer_isp || ns.user_isp) {
874 if (ns.conn == C_SYNC_SOURCE)
875 ns.conn = C_PAUSED_SYNC_S;
876 if (ns.conn == C_SYNC_TARGET)
877 ns.conn = C_PAUSED_SYNC_T;
879 if (ns.conn == C_PAUSED_SYNC_S)
880 ns.conn = C_SYNC_SOURCE;
881 if (ns.conn == C_PAUSED_SYNC_T)
882 ns.conn = C_SYNC_TARGET;
888 /* helper for __drbd_set_state */
889 static void set_ov_position(struct drbd_conf *mdev, enum drbd_conns cs)
891 if (cs == C_VERIFY_T) {
892 /* starting online verify from an arbitrary position
893 * does not fit well into the existing protocol.
894 * on C_VERIFY_T, we initialize ov_left and friends
895 * implicitly in receive_DataRequest once the
896 * first P_OV_REQUEST is received */
897 mdev->ov_start_sector = ~(sector_t)0;
899 unsigned long bit = BM_SECT_TO_BIT(mdev->ov_start_sector);
900 if (bit >= mdev->rs_total)
901 mdev->ov_start_sector =
902 BM_BIT_TO_SECT(mdev->rs_total - 1);
903 mdev->ov_position = mdev->ov_start_sector;
908 * __drbd_set_state() - Set a new DRBD state
909 * @mdev: DRBD device.
912 * @done: Optional completion, that will get completed after the after_state_ch() finished
914 * Caller needs to hold req_lock, and global_state_lock. Do not call directly.
916 int __drbd_set_state(struct drbd_conf *mdev,
917 union drbd_state ns, enum chg_state_flags flags,
918 struct completion *done)
922 int warn_sync_abort = 0;
923 struct after_state_chg_work *ascw;
927 ns = sanitize_state(mdev, os, ns, &warn_sync_abort);
930 return SS_NOTHING_TO_DO;
932 if (!(flags & CS_HARD)) {
933 /* pre-state-change checks ; only look at ns */
934 /* See drbd_state_sw_errors in drbd_strings.c */
936 rv = is_valid_state(mdev, ns);
937 if (rv < SS_SUCCESS) {
938 /* If the old state was illegal as well, then let
941 if (is_valid_state(mdev, os) == rv) {
942 dev_err(DEV, "Considering state change from bad state. "
943 "Error would be: '%s'\n",
944 drbd_set_st_err_str(rv));
945 print_st(mdev, "old", os);
946 print_st(mdev, "new", ns);
947 rv = is_valid_state_transition(mdev, ns, os);
950 rv = is_valid_state_transition(mdev, ns, os);
953 if (rv < SS_SUCCESS) {
954 if (flags & CS_VERBOSE)
955 print_st_err(mdev, os, ns, rv);
960 dev_warn(DEV, "Resync aborted.\n");
975 dev_info(DEV, "%s\n", pb);
978 /* solve the race between becoming unconfigured,
979 * worker doing the cleanup, and
980 * admin reconfiguring us:
981 * on (re)configure, first set CONFIG_PENDING,
982 * then wait for a potentially exiting worker,
983 * start the worker, and schedule one no_op.
984 * then proceed with configuration.
986 if (ns.disk == D_DISKLESS &&
987 ns.conn == C_STANDALONE &&
988 ns.role == R_SECONDARY &&
989 !test_and_set_bit(CONFIG_PENDING, &mdev->flags))
990 set_bit(DEVICE_DYING, &mdev->flags);
992 mdev->state.i = ns.i;
993 wake_up(&mdev->misc_wait);
994 wake_up(&mdev->state_wait);
996 /* post-state-change actions */
997 if (os.conn >= C_SYNC_SOURCE && ns.conn <= C_CONNECTED) {
998 set_bit(STOP_SYNC_TIMER, &mdev->flags);
999 mod_timer(&mdev->resync_timer, jiffies);
1002 /* aborted verify run. log the last position */
1003 if ((os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) &&
1004 ns.conn < C_CONNECTED) {
1005 mdev->ov_start_sector =
1006 BM_BIT_TO_SECT(mdev->rs_total - mdev->ov_left);
1007 dev_info(DEV, "Online Verify reached sector %llu\n",
1008 (unsigned long long)mdev->ov_start_sector);
1011 if ((os.conn == C_PAUSED_SYNC_T || os.conn == C_PAUSED_SYNC_S) &&
1012 (ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)) {
1013 dev_info(DEV, "Syncer continues.\n");
1014 mdev->rs_paused += (long)jiffies-(long)mdev->rs_mark_time;
1015 if (ns.conn == C_SYNC_TARGET) {
1016 if (!test_and_clear_bit(STOP_SYNC_TIMER, &mdev->flags))
1017 mod_timer(&mdev->resync_timer, jiffies);
1018 /* This if (!test_bit) is only needed for the case
1019 that a device that has ceased to used its timer,
1020 i.e. it is already in drbd_resync_finished() gets
1021 paused and resumed. */
1025 if ((os.conn == C_SYNC_TARGET || os.conn == C_SYNC_SOURCE) &&
1026 (ns.conn == C_PAUSED_SYNC_T || ns.conn == C_PAUSED_SYNC_S)) {
1027 dev_info(DEV, "Resync suspended\n");
1028 mdev->rs_mark_time = jiffies;
1029 if (ns.conn == C_PAUSED_SYNC_T)
1030 set_bit(STOP_SYNC_TIMER, &mdev->flags);
1033 if (os.conn == C_CONNECTED &&
1034 (ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T)) {
1035 mdev->ov_position = 0;
1037 mdev->rs_mark_left = drbd_bm_bits(mdev);
1038 if (mdev->agreed_pro_version >= 90)
1039 set_ov_position(mdev, ns.conn);
1041 mdev->ov_start_sector = 0;
1042 mdev->ov_left = mdev->rs_total
1043 - BM_SECT_TO_BIT(mdev->ov_position);
1045 mdev->rs_mark_time = jiffies;
1046 mdev->ov_last_oos_size = 0;
1047 mdev->ov_last_oos_start = 0;
1049 if (ns.conn == C_VERIFY_S) {
1050 dev_info(DEV, "Starting Online Verify from sector %llu\n",
1051 (unsigned long long)mdev->ov_position);
1052 mod_timer(&mdev->resync_timer, jiffies);
1056 if (get_ldev(mdev)) {
1057 u32 mdf = mdev->ldev->md.flags & ~(MDF_CONSISTENT|MDF_PRIMARY_IND|
1058 MDF_CONNECTED_IND|MDF_WAS_UP_TO_DATE|
1059 MDF_PEER_OUT_DATED|MDF_CRASHED_PRIMARY);
1061 if (test_bit(CRASHED_PRIMARY, &mdev->flags))
1062 mdf |= MDF_CRASHED_PRIMARY;
1063 if (mdev->state.role == R_PRIMARY ||
1064 (mdev->state.pdsk < D_INCONSISTENT && mdev->state.peer == R_PRIMARY))
1065 mdf |= MDF_PRIMARY_IND;
1066 if (mdev->state.conn > C_WF_REPORT_PARAMS)
1067 mdf |= MDF_CONNECTED_IND;
1068 if (mdev->state.disk > D_INCONSISTENT)
1069 mdf |= MDF_CONSISTENT;
1070 if (mdev->state.disk > D_OUTDATED)
1071 mdf |= MDF_WAS_UP_TO_DATE;
1072 if (mdev->state.pdsk <= D_OUTDATED && mdev->state.pdsk >= D_INCONSISTENT)
1073 mdf |= MDF_PEER_OUT_DATED;
1074 if (mdf != mdev->ldev->md.flags) {
1075 mdev->ldev->md.flags = mdf;
1076 drbd_md_mark_dirty(mdev);
1078 if (os.disk < D_CONSISTENT && ns.disk >= D_CONSISTENT)
1079 drbd_set_ed_uuid(mdev, mdev->ldev->md.uuid[UI_CURRENT]);
1083 /* Peer was forced D_UP_TO_DATE & R_PRIMARY, consider to resync */
1084 if (os.disk == D_INCONSISTENT && os.pdsk == D_INCONSISTENT &&
1085 os.peer == R_SECONDARY && ns.peer == R_PRIMARY)
1086 set_bit(CONSIDER_RESYNC, &mdev->flags);
1088 /* Receiver should clean up itself */
1089 if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING)
1090 drbd_thread_stop_nowait(&mdev->receiver);
1092 /* Now the receiver finished cleaning up itself, it should die */
1093 if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE)
1094 drbd_thread_stop_nowait(&mdev->receiver);
1096 /* Upon network failure, we need to restart the receiver. */
1097 if (os.conn > C_TEAR_DOWN &&
1098 ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT)
1099 drbd_thread_restart_nowait(&mdev->receiver);
1101 ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC);
1105 ascw->flags = flags;
1106 ascw->w.cb = w_after_state_ch;
1108 drbd_queue_work(&mdev->data.work, &ascw->w);
1110 dev_warn(DEV, "Could not kmalloc an ascw\n");
1116 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused)
1118 struct after_state_chg_work *ascw =
1119 container_of(w, struct after_state_chg_work, w);
1120 after_state_ch(mdev, ascw->os, ascw->ns, ascw->flags);
1121 if (ascw->flags & CS_WAIT_COMPLETE) {
1122 D_ASSERT(ascw->done != NULL);
1123 complete(ascw->done);
1130 static void abw_start_sync(struct drbd_conf *mdev, int rv)
1133 dev_err(DEV, "Writing the bitmap failed not starting resync.\n");
1134 _drbd_request_state(mdev, NS(conn, C_CONNECTED), CS_VERBOSE);
1138 switch (mdev->state.conn) {
1139 case C_STARTING_SYNC_T:
1140 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE);
1142 case C_STARTING_SYNC_S:
1143 drbd_start_resync(mdev, C_SYNC_SOURCE);
1149 * after_state_ch() - Perform after state change actions that may sleep
1150 * @mdev: DRBD device.
1155 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
1156 union drbd_state ns, enum chg_state_flags flags)
1158 enum drbd_fencing_p fp;
1160 if (os.conn != C_CONNECTED && ns.conn == C_CONNECTED) {
1161 clear_bit(CRASHED_PRIMARY, &mdev->flags);
1163 mdev->p_uuid[UI_FLAGS] &= ~((u64)2);
1167 if (get_ldev(mdev)) {
1168 fp = mdev->ldev->dc.fencing;
1172 /* Inform userspace about the change... */
1173 drbd_bcast_state(mdev, ns);
1175 if (!(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE) &&
1176 (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE))
1177 drbd_khelper(mdev, "pri-on-incon-degr");
1179 /* Here we have the actions that are performed after a
1180 state change. This function might sleep */
1182 if (fp == FP_STONITH && ns.susp) {
1183 /* case1: The outdate peer handler is successful:
1184 * case2: The connection was established again: */
1185 if ((os.pdsk > D_OUTDATED && ns.pdsk <= D_OUTDATED) ||
1186 (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)) {
1188 spin_lock_irq(&mdev->req_lock);
1189 _drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL);
1190 spin_unlock_irq(&mdev->req_lock);
1193 /* Do not change the order of the if above and the two below... */
1194 if (os.pdsk == D_DISKLESS && ns.pdsk > D_DISKLESS) { /* attach on the peer */
1195 drbd_send_uuids(mdev);
1196 drbd_send_state(mdev);
1198 if (os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S)
1199 drbd_queue_bitmap_io(mdev, &drbd_send_bitmap, NULL, "send_bitmap (WFBitMapS)");
1201 /* Lost contact to peer's copy of the data */
1202 if ((os.pdsk >= D_INCONSISTENT &&
1203 os.pdsk != D_UNKNOWN &&
1204 os.pdsk != D_OUTDATED)
1205 && (ns.pdsk < D_INCONSISTENT ||
1206 ns.pdsk == D_UNKNOWN ||
1207 ns.pdsk == D_OUTDATED)) {
1208 kfree(mdev->p_uuid);
1209 mdev->p_uuid = NULL;
1210 if (get_ldev(mdev)) {
1211 if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) &&
1212 mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) {
1213 drbd_uuid_new_current(mdev);
1214 drbd_send_uuids(mdev);
1220 if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) {
1221 if (ns.peer == R_PRIMARY && mdev->ldev->md.uuid[UI_BITMAP] == 0)
1222 drbd_uuid_new_current(mdev);
1224 /* D_DISKLESS Peer becomes secondary */
1225 if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
1226 drbd_al_to_on_disk_bm(mdev);
1230 /* Last part of the attaching process ... */
1231 if (ns.conn >= C_CONNECTED &&
1232 os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
1233 kfree(mdev->p_uuid); /* We expect to receive up-to-date UUIDs soon. */
1234 mdev->p_uuid = NULL; /* ...to not use the old ones in the mean time */
1235 drbd_send_sizes(mdev, 0); /* to start sync... */
1236 drbd_send_uuids(mdev);
1237 drbd_send_state(mdev);
1240 /* We want to pause/continue resync, tell peer. */
1241 if (ns.conn >= C_CONNECTED &&
1242 ((os.aftr_isp != ns.aftr_isp) ||
1243 (os.user_isp != ns.user_isp)))
1244 drbd_send_state(mdev);
1246 /* In case one of the isp bits got set, suspend other devices. */
1247 if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
1248 (ns.aftr_isp || ns.peer_isp || ns.user_isp))
1249 suspend_other_sg(mdev);
1251 /* Make sure the peer gets informed about eventual state
1252 changes (ISP bits) while we were in WFReportParams. */
1253 if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
1254 drbd_send_state(mdev);
1256 /* We are in the progress to start a full sync... */
1257 if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
1258 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S))
1259 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, &abw_start_sync, "set_n_write from StartingSync");
1261 /* We are invalidating our self... */
1262 if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED &&
1263 os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT)
1264 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL, "set_n_write from invalidate");
1266 if (os.disk > D_FAILED && ns.disk == D_FAILED) {
1267 enum drbd_io_error_p eh;
1270 if (get_ldev_if_state(mdev, D_FAILED)) {
1271 eh = mdev->ldev->dc.on_io_error;
1275 drbd_rs_cancel_all(mdev);
1276 /* since get_ldev() only works as long as disk>=D_INCONSISTENT,
1277 and it is D_DISKLESS here, local_cnt can only go down, it can
1278 not increase... It will reach zero */
1279 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1281 mdev->rs_failed = 0;
1282 atomic_set(&mdev->rs_pending_cnt, 0);
1284 spin_lock_irq(&mdev->req_lock);
1285 _drbd_set_state(_NS(mdev, disk, D_DISKLESS), CS_HARD, NULL);
1286 spin_unlock_irq(&mdev->req_lock);
1288 if (eh == EP_CALL_HELPER)
1289 drbd_khelper(mdev, "local-io-error");
1292 if (os.disk > D_DISKLESS && ns.disk == D_DISKLESS) {
1294 if (os.disk == D_FAILED) /* && ns.disk == D_DISKLESS*/ {
1295 if (drbd_send_state(mdev))
1296 dev_warn(DEV, "Notified peer that my disk is broken.\n");
1298 dev_err(DEV, "Sending state in drbd_io_error() failed\n");
1301 lc_destroy(mdev->resync);
1302 mdev->resync = NULL;
1303 lc_destroy(mdev->act_log);
1304 mdev->act_log = NULL;
1306 drbd_free_bc(mdev->ldev);
1307 mdev->ldev = NULL;);
1309 if (mdev->md_io_tmpp)
1310 __free_page(mdev->md_io_tmpp);
1313 /* Disks got bigger while they were detached */
1314 if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
1315 test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) {
1316 if (ns.conn == C_CONNECTED)
1317 resync_after_online_grow(mdev);
1320 /* A resync finished or aborted, wake paused devices... */
1321 if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) ||
1322 (os.peer_isp && !ns.peer_isp) ||
1323 (os.user_isp && !ns.user_isp))
1324 resume_next_sg(mdev);
1326 /* Upon network connection, we need to start the receiver */
1327 if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED)
1328 drbd_thread_start(&mdev->receiver);
1330 /* Terminate worker thread if we are unconfigured - it will be
1331 restarted as needed... */
1332 if (ns.disk == D_DISKLESS &&
1333 ns.conn == C_STANDALONE &&
1334 ns.role == R_SECONDARY) {
1335 if (os.aftr_isp != ns.aftr_isp)
1336 resume_next_sg(mdev);
1337 /* set in __drbd_set_state, unless CONFIG_PENDING was set */
1338 if (test_bit(DEVICE_DYING, &mdev->flags))
1339 drbd_thread_stop_nowait(&mdev->worker);
1346 static int drbd_thread_setup(void *arg)
1348 struct drbd_thread *thi = (struct drbd_thread *) arg;
1349 struct drbd_conf *mdev = thi->mdev;
1350 unsigned long flags;
1354 retval = thi->function(thi);
1356 spin_lock_irqsave(&thi->t_lock, flags);
1358 /* if the receiver has been "Exiting", the last thing it did
1359 * was set the conn state to "StandAlone",
1360 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
1361 * and receiver thread will be "started".
1362 * drbd_thread_start needs to set "Restarting" in that case.
1363 * t_state check and assignment needs to be within the same spinlock,
1364 * so either thread_start sees Exiting, and can remap to Restarting,
1365 * or thread_start see None, and can proceed as normal.
1368 if (thi->t_state == Restarting) {
1369 dev_info(DEV, "Restarting %s\n", current->comm);
1370 thi->t_state = Running;
1371 spin_unlock_irqrestore(&thi->t_lock, flags);
1376 thi->t_state = None;
1378 complete(&thi->stop);
1379 spin_unlock_irqrestore(&thi->t_lock, flags);
1381 dev_info(DEV, "Terminating %s\n", current->comm);
1383 /* Release mod reference taken when thread was started */
1384 module_put(THIS_MODULE);
1388 static void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi,
1389 int (*func) (struct drbd_thread *))
1391 spin_lock_init(&thi->t_lock);
1393 thi->t_state = None;
1394 thi->function = func;
1398 int drbd_thread_start(struct drbd_thread *thi)
1400 struct drbd_conf *mdev = thi->mdev;
1401 struct task_struct *nt;
1402 unsigned long flags;
1405 thi == &mdev->receiver ? "receiver" :
1406 thi == &mdev->asender ? "asender" :
1407 thi == &mdev->worker ? "worker" : "NONSENSE";
1409 /* is used from state engine doing drbd_thread_stop_nowait,
1410 * while holding the req lock irqsave */
1411 spin_lock_irqsave(&thi->t_lock, flags);
1413 switch (thi->t_state) {
1415 dev_info(DEV, "Starting %s thread (from %s [%d])\n",
1416 me, current->comm, current->pid);
1418 /* Get ref on module for thread - this is released when thread exits */
1419 if (!try_module_get(THIS_MODULE)) {
1420 dev_err(DEV, "Failed to get module reference in drbd_thread_start\n");
1421 spin_unlock_irqrestore(&thi->t_lock, flags);
1425 init_completion(&thi->stop);
1426 D_ASSERT(thi->task == NULL);
1427 thi->reset_cpu_mask = 1;
1428 thi->t_state = Running;
1429 spin_unlock_irqrestore(&thi->t_lock, flags);
1430 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
1432 nt = kthread_create(drbd_thread_setup, (void *) thi,
1433 "drbd%d_%s", mdev_to_minor(mdev), me);
1436 dev_err(DEV, "Couldn't start thread\n");
1438 module_put(THIS_MODULE);
1441 spin_lock_irqsave(&thi->t_lock, flags);
1443 thi->t_state = Running;
1444 spin_unlock_irqrestore(&thi->t_lock, flags);
1445 wake_up_process(nt);
1448 thi->t_state = Restarting;
1449 dev_info(DEV, "Restarting %s thread (from %s [%d])\n",
1450 me, current->comm, current->pid);
1455 spin_unlock_irqrestore(&thi->t_lock, flags);
1463 void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
1465 unsigned long flags;
1467 enum drbd_thread_state ns = restart ? Restarting : Exiting;
1469 /* may be called from state engine, holding the req lock irqsave */
1470 spin_lock_irqsave(&thi->t_lock, flags);
1472 if (thi->t_state == None) {
1473 spin_unlock_irqrestore(&thi->t_lock, flags);
1475 drbd_thread_start(thi);
1479 if (thi->t_state != ns) {
1480 if (thi->task == NULL) {
1481 spin_unlock_irqrestore(&thi->t_lock, flags);
1487 init_completion(&thi->stop);
1488 if (thi->task != current)
1489 force_sig(DRBD_SIGKILL, thi->task);
1493 spin_unlock_irqrestore(&thi->t_lock, flags);
1496 wait_for_completion(&thi->stop);
1501 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
1502 * @mdev: DRBD device.
1504 * Forces all threads of a device onto the same CPU. This is beneficial for
1505 * DRBD's performance. May be overwritten by user's configuration.
1507 void drbd_calc_cpu_mask(struct drbd_conf *mdev)
1511 /* user override. */
1512 if (cpumask_weight(mdev->cpu_mask))
1515 ord = mdev_to_minor(mdev) % cpumask_weight(cpu_online_mask);
1516 for_each_online_cpu(cpu) {
1518 cpumask_set_cpu(cpu, mdev->cpu_mask);
1522 /* should not be reached */
1523 cpumask_setall(mdev->cpu_mask);
1527 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
1528 * @mdev: DRBD device.
1530 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
1533 void drbd_thread_current_set_cpu(struct drbd_conf *mdev)
1535 struct task_struct *p = current;
1536 struct drbd_thread *thi =
1537 p == mdev->asender.task ? &mdev->asender :
1538 p == mdev->receiver.task ? &mdev->receiver :
1539 p == mdev->worker.task ? &mdev->worker :
1543 if (!thi->reset_cpu_mask)
1545 thi->reset_cpu_mask = 0;
1546 set_cpus_allowed_ptr(p, mdev->cpu_mask);
1550 /* the appropriate socket mutex must be held already */
1551 int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1552 enum drbd_packets cmd, struct p_header *h,
1553 size_t size, unsigned msg_flags)
1557 ERR_IF(!h) return FALSE;
1558 ERR_IF(!size) return FALSE;
1560 h->magic = BE_DRBD_MAGIC;
1561 h->command = cpu_to_be16(cmd);
1562 h->length = cpu_to_be16(size-sizeof(struct p_header));
1564 sent = drbd_send(mdev, sock, h, size, msg_flags);
1566 ok = (sent == size);
1568 dev_err(DEV, "short sent %s size=%d sent=%d\n",
1569 cmdname(cmd), (int)size, sent);
1573 /* don't pass the socket. we may only look at it
1574 * when we hold the appropriate socket mutex.
1576 int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1577 enum drbd_packets cmd, struct p_header *h, size_t size)
1580 struct socket *sock;
1582 if (use_data_socket) {
1583 mutex_lock(&mdev->data.mutex);
1584 sock = mdev->data.socket;
1586 mutex_lock(&mdev->meta.mutex);
1587 sock = mdev->meta.socket;
1590 /* drbd_disconnect() could have called drbd_free_sock()
1591 * while we were waiting in down()... */
1592 if (likely(sock != NULL))
1593 ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0);
1595 if (use_data_socket)
1596 mutex_unlock(&mdev->data.mutex);
1598 mutex_unlock(&mdev->meta.mutex);
1602 int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
1608 h.magic = BE_DRBD_MAGIC;
1609 h.command = cpu_to_be16(cmd);
1610 h.length = cpu_to_be16(size);
1612 if (!drbd_get_data_sock(mdev))
1616 drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0));
1618 drbd_send(mdev, mdev->data.socket, data, size, 0));
1620 drbd_put_data_sock(mdev);
1625 int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc)
1627 struct p_rs_param_89 *p;
1628 struct socket *sock;
1630 const int apv = mdev->agreed_pro_version;
1632 size = apv <= 87 ? sizeof(struct p_rs_param)
1633 : apv == 88 ? sizeof(struct p_rs_param)
1634 + strlen(mdev->sync_conf.verify_alg) + 1
1635 : /* 89 */ sizeof(struct p_rs_param_89);
1637 /* used from admin command context and receiver/worker context.
1638 * to avoid kmalloc, grab the socket right here,
1639 * then use the pre-allocated sbuf there */
1640 mutex_lock(&mdev->data.mutex);
1641 sock = mdev->data.socket;
1643 if (likely(sock != NULL)) {
1644 enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
1646 p = &mdev->data.sbuf.rs_param_89;
1648 /* initialize verify_alg and csums_alg */
1649 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
1651 p->rate = cpu_to_be32(sc->rate);
1654 strcpy(p->verify_alg, mdev->sync_conf.verify_alg);
1656 strcpy(p->csums_alg, mdev->sync_conf.csums_alg);
1658 rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
1660 rv = 0; /* not ok */
1662 mutex_unlock(&mdev->data.mutex);
1667 int drbd_send_protocol(struct drbd_conf *mdev)
1669 struct p_protocol *p;
1672 size = sizeof(struct p_protocol);
1674 if (mdev->agreed_pro_version >= 87)
1675 size += strlen(mdev->net_conf->integrity_alg) + 1;
1677 /* we must not recurse into our own queue,
1678 * as that is blocked during handshake */
1679 p = kmalloc(size, GFP_NOIO);
1683 p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol);
1684 p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p);
1685 p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p);
1686 p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p);
1687 p->want_lose = cpu_to_be32(mdev->net_conf->want_lose);
1688 p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries);
1690 if (mdev->agreed_pro_version >= 87)
1691 strcpy(p->integrity_alg, mdev->net_conf->integrity_alg);
1693 rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL,
1694 (struct p_header *)p, size);
1699 int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
1704 if (!get_ldev_if_state(mdev, D_NEGOTIATING))
1707 for (i = UI_CURRENT; i < UI_SIZE; i++)
1708 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
1710 mdev->comm_bm_set = drbd_bm_total_weight(mdev);
1711 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
1712 uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
1713 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
1714 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
1715 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
1719 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS,
1720 (struct p_header *)&p, sizeof(p));
1723 int drbd_send_uuids(struct drbd_conf *mdev)
1725 return _drbd_send_uuids(mdev, 0);
1728 int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
1730 return _drbd_send_uuids(mdev, 8);
1734 int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val)
1738 p.uuid = cpu_to_be64(val);
1740 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID,
1741 (struct p_header *)&p, sizeof(p));
1744 int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply)
1747 sector_t d_size, u_size;
1751 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
1752 D_ASSERT(mdev->ldev->backing_bdev);
1753 d_size = drbd_get_max_capacity(mdev->ldev);
1754 u_size = mdev->ldev->dc.disk_size;
1755 q_order_type = drbd_queue_order_type(mdev);
1756 p.queue_order_type = cpu_to_be32(drbd_queue_order_type(mdev));
1761 q_order_type = QUEUE_ORDERED_NONE;
1764 p.d_size = cpu_to_be64(d_size);
1765 p.u_size = cpu_to_be64(u_size);
1766 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
1767 p.max_segment_size = cpu_to_be32(queue_max_segment_size(mdev->rq_queue));
1768 p.queue_order_type = cpu_to_be32(q_order_type);
1770 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES,
1771 (struct p_header *)&p, sizeof(p));
1776 * drbd_send_state() - Sends the drbd state to the peer
1777 * @mdev: DRBD device.
1779 int drbd_send_state(struct drbd_conf *mdev)
1781 struct socket *sock;
1785 /* Grab state lock so we wont send state if we're in the middle
1786 * of a cluster wide state change on another thread */
1787 drbd_state_lock(mdev);
1789 mutex_lock(&mdev->data.mutex);
1791 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
1792 sock = mdev->data.socket;
1794 if (likely(sock != NULL)) {
1795 ok = _drbd_send_cmd(mdev, sock, P_STATE,
1796 (struct p_header *)&p, sizeof(p), 0);
1799 mutex_unlock(&mdev->data.mutex);
1801 drbd_state_unlock(mdev);
1805 int drbd_send_state_req(struct drbd_conf *mdev,
1806 union drbd_state mask, union drbd_state val)
1808 struct p_req_state p;
1810 p.mask = cpu_to_be32(mask.i);
1811 p.val = cpu_to_be32(val.i);
1813 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ,
1814 (struct p_header *)&p, sizeof(p));
1817 int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode)
1819 struct p_req_state_reply p;
1821 p.retcode = cpu_to_be32(retcode);
1823 return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY,
1824 (struct p_header *)&p, sizeof(p));
1827 int fill_bitmap_rle_bits(struct drbd_conf *mdev,
1828 struct p_compressed_bm *p,
1829 struct bm_xfer_ctx *c)
1831 struct bitstream bs;
1832 unsigned long plain_bits;
1839 /* may we use this feature? */
1840 if ((mdev->sync_conf.use_rle == 0) ||
1841 (mdev->agreed_pro_version < 90))
1844 if (c->bit_offset >= c->bm_bits)
1845 return 0; /* nothing to do. */
1847 /* use at most thus many bytes */
1848 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
1849 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
1850 /* plain bits covered in this code string */
1853 /* p->encoding & 0x80 stores whether the first run length is set.
1854 * bit offset is implicit.
1855 * start with toggle == 2 to be able to tell the first iteration */
1858 /* see how much plain bits we can stuff into one packet
1859 * using RLE and VLI. */
1861 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
1862 : _drbd_bm_find_next(mdev, c->bit_offset);
1865 rl = tmp - c->bit_offset;
1867 if (toggle == 2) { /* first iteration */
1869 /* the first checked bit was set,
1870 * store start value, */
1871 DCBP_set_start(p, 1);
1872 /* but skip encoding of zero run length */
1876 DCBP_set_start(p, 0);
1879 /* paranoia: catch zero runlength.
1880 * can only happen if bitmap is modified while we scan it. */
1882 dev_err(DEV, "unexpected zero runlength while encoding bitmap "
1883 "t:%u bo:%lu\n", toggle, c->bit_offset);
1887 bits = vli_encode_bits(&bs, rl);
1888 if (bits == -ENOBUFS) /* buffer full */
1891 dev_err(DEV, "error while encoding bitmap: %d\n", bits);
1897 c->bit_offset = tmp;
1898 } while (c->bit_offset < c->bm_bits);
1900 len = bs.cur.b - p->code + !!bs.cur.bit;
1902 if (plain_bits < (len << 3)) {
1903 /* incompressible with this method.
1904 * we need to rewind both word and bit position. */
1905 c->bit_offset -= plain_bits;
1906 bm_xfer_ctx_bit_to_word_offset(c);
1907 c->bit_offset = c->word_offset * BITS_PER_LONG;
1911 /* RLE + VLI was able to compress it just fine.
1912 * update c->word_offset. */
1913 bm_xfer_ctx_bit_to_word_offset(c);
1915 /* store pad_bits */
1916 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
1921 enum { OK, FAILED, DONE }
1922 send_bitmap_rle_or_plain(struct drbd_conf *mdev,
1923 struct p_header *h, struct bm_xfer_ctx *c)
1925 struct p_compressed_bm *p = (void*)h;
1926 unsigned long num_words;
1930 len = fill_bitmap_rle_bits(mdev, p, c);
1936 DCBP_set_code(p, RLE_VLI_Bits);
1937 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h,
1938 sizeof(*p) + len, 0);
1941 c->bytes[0] += sizeof(*p) + len;
1943 if (c->bit_offset >= c->bm_bits)
1946 /* was not compressible.
1947 * send a buffer full of plain text bits instead. */
1948 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
1949 len = num_words * sizeof(long);
1951 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
1952 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP,
1953 h, sizeof(struct p_header) + len, 0);
1954 c->word_offset += num_words;
1955 c->bit_offset = c->word_offset * BITS_PER_LONG;
1958 c->bytes[1] += sizeof(struct p_header) + len;
1960 if (c->bit_offset > c->bm_bits)
1961 c->bit_offset = c->bm_bits;
1963 ok = ok ? ((len == 0) ? DONE : OK) : FAILED;
1966 INFO_bm_xfer_stats(mdev, "send", c);
1970 /* See the comment at receive_bitmap() */
1971 int _drbd_send_bitmap(struct drbd_conf *mdev)
1973 struct bm_xfer_ctx c;
1977 ERR_IF(!mdev->bitmap) return FALSE;
1979 /* maybe we should use some per thread scratch page,
1980 * and allocate that during initial device creation? */
1981 p = (struct p_header *) __get_free_page(GFP_NOIO);
1983 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
1987 if (get_ldev(mdev)) {
1988 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
1989 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
1990 drbd_bm_set_all(mdev);
1991 if (drbd_bm_write(mdev)) {
1992 /* write_bm did fail! Leave full sync flag set in Meta P_DATA
1993 * but otherwise process as per normal - need to tell other
1994 * side that a full resync is required! */
1995 dev_err(DEV, "Failed to write bitmap to disk!\n");
1997 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2004 c = (struct bm_xfer_ctx) {
2005 .bm_bits = drbd_bm_bits(mdev),
2006 .bm_words = drbd_bm_words(mdev),
2010 ret = send_bitmap_rle_or_plain(mdev, p, &c);
2011 } while (ret == OK);
2013 free_page((unsigned long) p);
2014 return (ret == DONE);
2017 int drbd_send_bitmap(struct drbd_conf *mdev)
2021 if (!drbd_get_data_sock(mdev))
2023 err = !_drbd_send_bitmap(mdev);
2024 drbd_put_data_sock(mdev);
2028 int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
2031 struct p_barrier_ack p;
2033 p.barrier = barrier_nr;
2034 p.set_size = cpu_to_be32(set_size);
2036 if (mdev->state.conn < C_CONNECTED)
2038 ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK,
2039 (struct p_header *)&p, sizeof(p));
2044 * _drbd_send_ack() - Sends an ack packet
2045 * @mdev: DRBD device.
2046 * @cmd: Packet command code.
2047 * @sector: sector, needs to be in big endian byte order
2048 * @blksize: size in byte, needs to be in big endian byte order
2049 * @block_id: Id, big endian byte order
2051 static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
2057 struct p_block_ack p;
2060 p.block_id = block_id;
2061 p.blksize = blksize;
2062 p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq));
2064 if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED)
2066 ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd,
2067 (struct p_header *)&p, sizeof(p));
2071 int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
2074 const int header_size = sizeof(struct p_data)
2075 - sizeof(struct p_header);
2076 int data_size = ((struct p_header *)dp)->length - header_size;
2078 return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
2082 int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
2083 struct p_block_req *rp)
2085 return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
2089 * drbd_send_ack() - Sends an ack packet
2090 * @mdev: DRBD device.
2091 * @cmd: Packet command code.
2094 int drbd_send_ack(struct drbd_conf *mdev,
2095 enum drbd_packets cmd, struct drbd_epoch_entry *e)
2097 return _drbd_send_ack(mdev, cmd,
2098 cpu_to_be64(e->sector),
2099 cpu_to_be32(e->size),
2103 /* This function misuses the block_id field to signal if the blocks
2104 * are is sync or not. */
2105 int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
2106 sector_t sector, int blksize, u64 block_id)
2108 return _drbd_send_ack(mdev, cmd,
2109 cpu_to_be64(sector),
2110 cpu_to_be32(blksize),
2111 cpu_to_be64(block_id));
2114 int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
2115 sector_t sector, int size, u64 block_id)
2118 struct p_block_req p;
2120 p.sector = cpu_to_be64(sector);
2121 p.block_id = block_id;
2122 p.blksize = cpu_to_be32(size);
2124 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd,
2125 (struct p_header *)&p, sizeof(p));
2129 int drbd_send_drequest_csum(struct drbd_conf *mdev,
2130 sector_t sector, int size,
2131 void *digest, int digest_size,
2132 enum drbd_packets cmd)
2135 struct p_block_req p;
2137 p.sector = cpu_to_be64(sector);
2138 p.block_id = BE_DRBD_MAGIC + 0xbeef;
2139 p.blksize = cpu_to_be32(size);
2141 p.head.magic = BE_DRBD_MAGIC;
2142 p.head.command = cpu_to_be16(cmd);
2143 p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header) + digest_size);
2145 mutex_lock(&mdev->data.mutex);
2147 ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0));
2148 ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0));
2150 mutex_unlock(&mdev->data.mutex);
2155 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
2158 struct p_block_req p;
2160 p.sector = cpu_to_be64(sector);
2161 p.block_id = BE_DRBD_MAGIC + 0xbabe;
2162 p.blksize = cpu_to_be32(size);
2164 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST,
2165 (struct p_header *)&p, sizeof(p));
2169 /* called on sndtimeo
2170 * returns FALSE if we should retry,
2171 * TRUE if we think connection is dead
2173 static int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock)
2176 /* long elapsed = (long)(jiffies - mdev->last_received); */
2178 drop_it = mdev->meta.socket == sock
2179 || !mdev->asender.task
2180 || get_t_state(&mdev->asender) != Running
2181 || mdev->state.conn < C_CONNECTED;
2186 drop_it = !--mdev->ko_count;
2188 dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
2189 current->comm, current->pid, mdev->ko_count);
2193 return drop_it; /* && (mdev->state == R_PRIMARY) */;
2196 /* The idea of sendpage seems to be to put some kind of reference
2197 * to the page into the skb, and to hand it over to the NIC. In
2198 * this process get_page() gets called.
2200 * As soon as the page was really sent over the network put_page()
2201 * gets called by some part of the network layer. [ NIC driver? ]
2203 * [ get_page() / put_page() increment/decrement the count. If count
2204 * reaches 0 the page will be freed. ]
2206 * This works nicely with pages from FSs.
2207 * But this means that in protocol A we might signal IO completion too early!
2209 * In order not to corrupt data during a resync we must make sure
2210 * that we do not reuse our own buffer pages (EEs) to early, therefore
2211 * we have the net_ee list.
2213 * XFS seems to have problems, still, it submits pages with page_count == 0!
2214 * As a workaround, we disable sendpage on pages
2215 * with page_count == 0 or PageSlab.
2217 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
2218 int offset, size_t size)
2220 int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, 0);
2223 mdev->send_cnt += size>>9;
2224 return sent == size;
2227 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
2228 int offset, size_t size)
2230 mm_segment_t oldfs = get_fs();
2234 /* e.g. XFS meta- & log-data is in slab pages, which have a
2235 * page_count of 0 and/or have PageSlab() set.
2236 * we cannot use send_page for those, as that does get_page();
2237 * put_page(); and would cause either a VM_BUG directly, or
2238 * __page_cache_release a page that would actually still be referenced
2239 * by someone, leading to some obscure delayed Oops somewhere else. */
2240 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
2241 return _drbd_no_send_page(mdev, page, offset, size);
2243 drbd_update_congested(mdev);
2246 sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page,
2249 if (sent == -EAGAIN) {
2250 if (we_should_drop_the_connection(mdev,
2257 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
2258 __func__, (int)size, len, sent);
2263 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
2265 clear_bit(NET_CONGESTED, &mdev->flags);
2269 mdev->send_cnt += size>>9;
2273 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
2275 struct bio_vec *bvec;
2277 __bio_for_each_segment(bvec, bio, i, 0) {
2278 if (!_drbd_no_send_page(mdev, bvec->bv_page,
2279 bvec->bv_offset, bvec->bv_len))
2285 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
2287 struct bio_vec *bvec;
2289 __bio_for_each_segment(bvec, bio, i, 0) {
2290 if (!_drbd_send_page(mdev, bvec->bv_page,
2291 bvec->bv_offset, bvec->bv_len))
2298 /* Used to send write requests
2299 * R_PRIMARY -> Peer (P_DATA)
2301 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
2305 unsigned int dp_flags = 0;
2309 if (!drbd_get_data_sock(mdev))
2312 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2313 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2315 p.head.magic = BE_DRBD_MAGIC;
2316 p.head.command = cpu_to_be16(P_DATA);
2318 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + req->size);
2320 p.sector = cpu_to_be64(req->sector);
2321 p.block_id = (unsigned long)req;
2322 p.seq_num = cpu_to_be32(req->seq_num =
2323 atomic_add_return(1, &mdev->packet_seq));
2326 /* NOTE: no need to check if barriers supported here as we would
2327 * not pass the test in make_request_common in that case
2329 if (bio_rw_flagged(req->master_bio, BIO_RW_BARRIER)) {
2330 dev_err(DEV, "ASSERT FAILED would have set DP_HARDBARRIER\n");
2331 /* dp_flags |= DP_HARDBARRIER; */
2333 if (bio_rw_flagged(req->master_bio, BIO_RW_SYNCIO))
2334 dp_flags |= DP_RW_SYNC;
2335 /* for now handle SYNCIO and UNPLUG
2336 * as if they still were one and the same flag */
2337 if (bio_rw_flagged(req->master_bio, BIO_RW_UNPLUG))
2338 dp_flags |= DP_RW_SYNC;
2339 if (mdev->state.conn >= C_SYNC_SOURCE &&
2340 mdev->state.conn <= C_PAUSED_SYNC_T)
2341 dp_flags |= DP_MAY_SET_IN_SYNC;
2343 p.dp_flags = cpu_to_be32(dp_flags);
2344 set_bit(UNPLUG_REMOTE, &mdev->flags);
2346 drbd_send(mdev, mdev->data.socket, &p, sizeof(p), MSG_MORE));
2348 dgb = mdev->int_dig_out;
2349 drbd_csum(mdev, mdev->integrity_w_tfm, req->master_bio, dgb);
2350 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2353 if (mdev->net_conf->wire_protocol == DRBD_PROT_A)
2354 ok = _drbd_send_bio(mdev, req->master_bio);
2356 ok = _drbd_send_zc_bio(mdev, req->master_bio);
2359 drbd_put_data_sock(mdev);
2363 /* answer packet, used to send data back for read requests:
2364 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
2365 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
2367 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
2368 struct drbd_epoch_entry *e)
2375 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2376 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2378 p.head.magic = BE_DRBD_MAGIC;
2379 p.head.command = cpu_to_be16(cmd);
2381 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + e->size);
2383 p.sector = cpu_to_be64(e->sector);
2384 p.block_id = e->block_id;
2385 /* p.seq_num = 0; No sequence numbers here.. */
2387 /* Only called by our kernel thread.
2388 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
2389 * in response to admin command or module unload.
2391 if (!drbd_get_data_sock(mdev))
2394 ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p,
2395 sizeof(p), MSG_MORE);
2397 dgb = mdev->int_dig_out;
2398 drbd_csum(mdev, mdev->integrity_w_tfm, e->private_bio, dgb);
2399 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2402 ok = _drbd_send_zc_bio(mdev, e->private_bio);
2404 drbd_put_data_sock(mdev);
2409 drbd_send distinguishes two cases:
2411 Packets sent via the data socket "sock"
2412 and packets sent via the meta data socket "msock"
2415 -----------------+-------------------------+------------------------------
2416 timeout conf.timeout / 2 conf.timeout / 2
2417 timeout action send a ping via msock Abort communication
2418 and close all sockets
2422 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
2424 int drbd_send(struct drbd_conf *mdev, struct socket *sock,
2425 void *buf, size_t size, unsigned msg_flags)
2434 /* THINK if (signal_pending) return ... ? */
2439 msg.msg_name = NULL;
2440 msg.msg_namelen = 0;
2441 msg.msg_control = NULL;
2442 msg.msg_controllen = 0;
2443 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
2445 if (sock == mdev->data.socket) {
2446 mdev->ko_count = mdev->net_conf->ko_count;
2447 drbd_update_congested(mdev);
2451 * tcp_sendmsg does _not_ use its size parameter at all ?
2453 * -EAGAIN on timeout, -EINTR on signal.
2456 * do we need to block DRBD_SIG if sock == &meta.socket ??
2457 * otherwise wake_asender() might interrupt some send_*Ack !
2459 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
2460 if (rv == -EAGAIN) {
2461 if (we_should_drop_the_connection(mdev, sock))
2468 flush_signals(current);
2476 } while (sent < size);
2478 if (sock == mdev->data.socket)
2479 clear_bit(NET_CONGESTED, &mdev->flags);
2482 if (rv != -EAGAIN) {
2483 dev_err(DEV, "%s_sendmsg returned %d\n",
2484 sock == mdev->meta.socket ? "msock" : "sock",
2486 drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE));
2488 drbd_force_state(mdev, NS(conn, C_TIMEOUT));
2494 static int drbd_open(struct block_device *bdev, fmode_t mode)
2496 struct drbd_conf *mdev = bdev->bd_disk->private_data;
2497 unsigned long flags;
2500 spin_lock_irqsave(&mdev->req_lock, flags);
2501 /* to have a stable mdev->state.role
2502 * and no race with updating open_cnt */
2504 if (mdev->state.role != R_PRIMARY) {
2505 if (mode & FMODE_WRITE)
2507 else if (!allow_oos)
2513 spin_unlock_irqrestore(&mdev->req_lock, flags);
2518 static int drbd_release(struct gendisk *gd, fmode_t mode)
2520 struct drbd_conf *mdev = gd->private_data;
2525 static void drbd_unplug_fn(struct request_queue *q)
2527 struct drbd_conf *mdev = q->queuedata;
2530 spin_lock_irq(q->queue_lock);
2532 spin_unlock_irq(q->queue_lock);
2534 /* only if connected */
2535 spin_lock_irq(&mdev->req_lock);
2536 if (mdev->state.pdsk >= D_INCONSISTENT && mdev->state.conn >= C_CONNECTED) {
2537 D_ASSERT(mdev->state.role == R_PRIMARY);
2538 if (test_and_clear_bit(UNPLUG_REMOTE, &mdev->flags)) {
2539 /* add to the data.work queue,
2540 * unless already queued.
2541 * XXX this might be a good addition to drbd_queue_work
2542 * anyways, to detect "double queuing" ... */
2543 if (list_empty(&mdev->unplug_work.list))
2544 drbd_queue_work(&mdev->data.work,
2545 &mdev->unplug_work);
2548 spin_unlock_irq(&mdev->req_lock);
2550 if (mdev->state.disk >= D_INCONSISTENT)
2554 static void drbd_set_defaults(struct drbd_conf *mdev)
2556 mdev->sync_conf.after = DRBD_AFTER_DEF;
2557 mdev->sync_conf.rate = DRBD_RATE_DEF;
2558 mdev->sync_conf.al_extents = DRBD_AL_EXTENTS_DEF;
2559 mdev->state = (union drbd_state) {
2560 { .role = R_SECONDARY,
2562 .conn = C_STANDALONE,
2569 void drbd_init_set_defaults(struct drbd_conf *mdev)
2571 /* the memset(,0,) did most of this.
2572 * note: only assignments, no allocation in here */
2574 drbd_set_defaults(mdev);
2576 /* for now, we do NOT yet support it,
2577 * even though we start some framework
2578 * to eventually support barriers */
2579 set_bit(NO_BARRIER_SUPP, &mdev->flags);
2581 atomic_set(&mdev->ap_bio_cnt, 0);
2582 atomic_set(&mdev->ap_pending_cnt, 0);
2583 atomic_set(&mdev->rs_pending_cnt, 0);
2584 atomic_set(&mdev->unacked_cnt, 0);
2585 atomic_set(&mdev->local_cnt, 0);
2586 atomic_set(&mdev->net_cnt, 0);
2587 atomic_set(&mdev->packet_seq, 0);
2588 atomic_set(&mdev->pp_in_use, 0);
2590 mutex_init(&mdev->md_io_mutex);
2591 mutex_init(&mdev->data.mutex);
2592 mutex_init(&mdev->meta.mutex);
2593 sema_init(&mdev->data.work.s, 0);
2594 sema_init(&mdev->meta.work.s, 0);
2595 mutex_init(&mdev->state_mutex);
2597 spin_lock_init(&mdev->data.work.q_lock);
2598 spin_lock_init(&mdev->meta.work.q_lock);
2600 spin_lock_init(&mdev->al_lock);
2601 spin_lock_init(&mdev->req_lock);
2602 spin_lock_init(&mdev->peer_seq_lock);
2603 spin_lock_init(&mdev->epoch_lock);
2605 INIT_LIST_HEAD(&mdev->active_ee);
2606 INIT_LIST_HEAD(&mdev->sync_ee);
2607 INIT_LIST_HEAD(&mdev->done_ee);
2608 INIT_LIST_HEAD(&mdev->read_ee);
2609 INIT_LIST_HEAD(&mdev->net_ee);
2610 INIT_LIST_HEAD(&mdev->resync_reads);
2611 INIT_LIST_HEAD(&mdev->data.work.q);
2612 INIT_LIST_HEAD(&mdev->meta.work.q);
2613 INIT_LIST_HEAD(&mdev->resync_work.list);
2614 INIT_LIST_HEAD(&mdev->unplug_work.list);
2615 INIT_LIST_HEAD(&mdev->md_sync_work.list);
2616 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
2617 mdev->resync_work.cb = w_resync_inactive;
2618 mdev->unplug_work.cb = w_send_write_hint;
2619 mdev->md_sync_work.cb = w_md_sync;
2620 mdev->bm_io_work.w.cb = w_bitmap_io;
2621 init_timer(&mdev->resync_timer);
2622 init_timer(&mdev->md_sync_timer);
2623 mdev->resync_timer.function = resync_timer_fn;
2624 mdev->resync_timer.data = (unsigned long) mdev;
2625 mdev->md_sync_timer.function = md_sync_timer_fn;
2626 mdev->md_sync_timer.data = (unsigned long) mdev;
2628 init_waitqueue_head(&mdev->misc_wait);
2629 init_waitqueue_head(&mdev->state_wait);
2630 init_waitqueue_head(&mdev->ee_wait);
2631 init_waitqueue_head(&mdev->al_wait);
2632 init_waitqueue_head(&mdev->seq_wait);
2634 drbd_thread_init(mdev, &mdev->receiver, drbdd_init);
2635 drbd_thread_init(mdev, &mdev->worker, drbd_worker);
2636 drbd_thread_init(mdev, &mdev->asender, drbd_asender);
2638 mdev->agreed_pro_version = PRO_VERSION_MAX;
2639 mdev->write_ordering = WO_bio_barrier;
2640 mdev->resync_wenr = LC_FREE;
2643 void drbd_mdev_cleanup(struct drbd_conf *mdev)
2645 if (mdev->receiver.t_state != None)
2646 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
2647 mdev->receiver.t_state);
2649 /* no need to lock it, I'm the only thread alive */
2650 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
2651 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
2662 mdev->rs_mark_left =
2663 mdev->rs_mark_time = 0;
2664 D_ASSERT(mdev->net_conf == NULL);
2666 drbd_set_my_capacity(mdev, 0);
2668 /* maybe never allocated. */
2669 drbd_bm_resize(mdev, 0);
2670 drbd_bm_cleanup(mdev);
2673 drbd_free_resources(mdev);
2676 * currently we drbd_init_ee only on module load, so
2677 * we may do drbd_release_ee only on module unload!
2679 D_ASSERT(list_empty(&mdev->active_ee));
2680 D_ASSERT(list_empty(&mdev->sync_ee));
2681 D_ASSERT(list_empty(&mdev->done_ee));
2682 D_ASSERT(list_empty(&mdev->read_ee));
2683 D_ASSERT(list_empty(&mdev->net_ee));
2684 D_ASSERT(list_empty(&mdev->resync_reads));
2685 D_ASSERT(list_empty(&mdev->data.work.q));
2686 D_ASSERT(list_empty(&mdev->meta.work.q));
2687 D_ASSERT(list_empty(&mdev->resync_work.list));
2688 D_ASSERT(list_empty(&mdev->unplug_work.list));
2693 static void drbd_destroy_mempools(void)
2697 while (drbd_pp_pool) {
2698 page = drbd_pp_pool;
2699 drbd_pp_pool = (struct page *)page_private(page);
2704 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
2706 if (drbd_ee_mempool)
2707 mempool_destroy(drbd_ee_mempool);
2708 if (drbd_request_mempool)
2709 mempool_destroy(drbd_request_mempool);
2711 kmem_cache_destroy(drbd_ee_cache);
2712 if (drbd_request_cache)
2713 kmem_cache_destroy(drbd_request_cache);
2714 if (drbd_bm_ext_cache)
2715 kmem_cache_destroy(drbd_bm_ext_cache);
2716 if (drbd_al_ext_cache)
2717 kmem_cache_destroy(drbd_al_ext_cache);
2719 drbd_ee_mempool = NULL;
2720 drbd_request_mempool = NULL;
2721 drbd_ee_cache = NULL;
2722 drbd_request_cache = NULL;
2723 drbd_bm_ext_cache = NULL;
2724 drbd_al_ext_cache = NULL;
2729 static int drbd_create_mempools(void)
2732 const int number = (DRBD_MAX_SEGMENT_SIZE/PAGE_SIZE) * minor_count;
2735 /* prepare our caches and mempools */
2736 drbd_request_mempool = NULL;
2737 drbd_ee_cache = NULL;
2738 drbd_request_cache = NULL;
2739 drbd_bm_ext_cache = NULL;
2740 drbd_al_ext_cache = NULL;
2741 drbd_pp_pool = NULL;
2744 drbd_request_cache = kmem_cache_create(
2745 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
2746 if (drbd_request_cache == NULL)
2749 drbd_ee_cache = kmem_cache_create(
2750 "drbd_ee", sizeof(struct drbd_epoch_entry), 0, 0, NULL);
2751 if (drbd_ee_cache == NULL)
2754 drbd_bm_ext_cache = kmem_cache_create(
2755 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
2756 if (drbd_bm_ext_cache == NULL)
2759 drbd_al_ext_cache = kmem_cache_create(
2760 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
2761 if (drbd_al_ext_cache == NULL)
2765 drbd_request_mempool = mempool_create(number,
2766 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
2767 if (drbd_request_mempool == NULL)
2770 drbd_ee_mempool = mempool_create(number,
2771 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2772 if (drbd_request_mempool == NULL)
2775 /* drbd's page pool */
2776 spin_lock_init(&drbd_pp_lock);
2778 for (i = 0; i < number; i++) {
2779 page = alloc_page(GFP_HIGHUSER);
2782 set_page_private(page, (unsigned long)drbd_pp_pool);
2783 drbd_pp_pool = page;
2785 drbd_pp_vacant = number;
2790 drbd_destroy_mempools(); /* in case we allocated some */
2794 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
2797 /* just so we have it. you never know what interesting things we
2798 * might want to do here some day...
2804 static struct notifier_block drbd_notifier = {
2805 .notifier_call = drbd_notify_sys,
2808 static void drbd_release_ee_lists(struct drbd_conf *mdev)
2812 rr = drbd_release_ee(mdev, &mdev->active_ee);
2814 dev_err(DEV, "%d EEs in active list found!\n", rr);
2816 rr = drbd_release_ee(mdev, &mdev->sync_ee);
2818 dev_err(DEV, "%d EEs in sync list found!\n", rr);
2820 rr = drbd_release_ee(mdev, &mdev->read_ee);
2822 dev_err(DEV, "%d EEs in read list found!\n", rr);
2824 rr = drbd_release_ee(mdev, &mdev->done_ee);
2826 dev_err(DEV, "%d EEs in done list found!\n", rr);
2828 rr = drbd_release_ee(mdev, &mdev->net_ee);
2830 dev_err(DEV, "%d EEs in net list found!\n", rr);
2833 /* caution. no locking.
2834 * currently only used from module cleanup code. */
2835 static void drbd_delete_device(unsigned int minor)
2837 struct drbd_conf *mdev = minor_to_mdev(minor);
2842 /* paranoia asserts */
2843 if (mdev->open_cnt != 0)
2844 dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,
2845 __FILE__ , __LINE__);
2847 ERR_IF (!list_empty(&mdev->data.work.q)) {
2848 struct list_head *lp;
2849 list_for_each(lp, &mdev->data.work.q) {
2850 dev_err(DEV, "lp = %p\n", lp);
2853 /* end paranoia asserts */
2855 del_gendisk(mdev->vdisk);
2857 /* cleanup stuff that may have been allocated during
2858 * device (re-)configuration or state changes */
2860 if (mdev->this_bdev)
2861 bdput(mdev->this_bdev);
2863 drbd_free_resources(mdev);
2865 drbd_release_ee_lists(mdev);
2867 /* should be free'd on disconnect? */
2868 kfree(mdev->ee_hash);
2870 mdev->ee_hash_s = 0;
2871 mdev->ee_hash = NULL;
2874 lc_destroy(mdev->act_log);
2875 lc_destroy(mdev->resync);
2877 kfree(mdev->p_uuid);
2878 /* mdev->p_uuid = NULL; */
2880 kfree(mdev->int_dig_out);
2881 kfree(mdev->int_dig_in);
2882 kfree(mdev->int_dig_vv);
2884 /* cleanup the rest that has been
2885 * allocated from drbd_new_device
2886 * and actually free the mdev itself */
2887 drbd_free_mdev(mdev);
2890 static void drbd_cleanup(void)
2894 unregister_reboot_notifier(&drbd_notifier);
2900 remove_proc_entry("drbd", NULL);
2903 drbd_delete_device(i);
2904 drbd_destroy_mempools();
2909 unregister_blkdev(DRBD_MAJOR, "drbd");
2911 printk(KERN_INFO "drbd: module cleanup done.\n");
2915 * drbd_congested() - Callback for pdflush
2916 * @congested_data: User data
2917 * @bdi_bits: Bits pdflush is currently interested in
2919 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
2921 static int drbd_congested(void *congested_data, int bdi_bits)
2923 struct drbd_conf *mdev = congested_data;
2924 struct request_queue *q;
2928 if (!__inc_ap_bio_cond(mdev)) {
2929 /* DRBD has frozen IO */
2935 if (get_ldev(mdev)) {
2936 q = bdev_get_queue(mdev->ldev->backing_bdev);
2937 r = bdi_congested(&q->backing_dev_info, bdi_bits);
2943 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) {
2944 r |= (1 << BDI_async_congested);
2945 reason = reason == 'b' ? 'a' : 'n';
2949 mdev->congestion_reason = reason;
2953 struct drbd_conf *drbd_new_device(unsigned int minor)
2955 struct drbd_conf *mdev;
2956 struct gendisk *disk;
2957 struct request_queue *q;
2959 /* GFP_KERNEL, we are outside of all write-out paths */
2960 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
2963 if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL))
2964 goto out_no_cpumask;
2966 mdev->minor = minor;
2968 drbd_init_set_defaults(mdev);
2970 q = blk_alloc_queue(GFP_KERNEL);
2974 q->queuedata = mdev;
2975 blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE);
2977 disk = alloc_disk(1);
2982 set_disk_ro(disk, TRUE);
2985 disk->major = DRBD_MAJOR;
2986 disk->first_minor = minor;
2987 disk->fops = &drbd_ops;
2988 sprintf(disk->disk_name, "drbd%d", minor);
2989 disk->private_data = mdev;
2991 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
2992 /* we have no partitions. we contain only ourselves. */
2993 mdev->this_bdev->bd_contains = mdev->this_bdev;
2995 q->backing_dev_info.congested_fn = drbd_congested;
2996 q->backing_dev_info.congested_data = mdev;
2998 blk_queue_make_request(q, drbd_make_request_26);
2999 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
3000 blk_queue_merge_bvec(q, drbd_merge_bvec);
3001 q->queue_lock = &mdev->req_lock; /* needed since we use */
3002 /* plugging on a queue, that actually has no requests! */
3003 q->unplug_fn = drbd_unplug_fn;
3005 mdev->md_io_page = alloc_page(GFP_KERNEL);
3006 if (!mdev->md_io_page)
3007 goto out_no_io_page;
3009 if (drbd_bm_init(mdev))
3011 /* no need to lock access, we are still initializing this minor device. */
3015 mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL);
3016 if (!mdev->app_reads_hash)
3017 goto out_no_app_reads;
3019 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
3020 if (!mdev->current_epoch)
3023 INIT_LIST_HEAD(&mdev->current_epoch->list);
3028 /* out_whatever_else:
3029 kfree(mdev->current_epoch); */
3031 kfree(mdev->app_reads_hash);
3035 drbd_bm_cleanup(mdev);
3037 __free_page(mdev->md_io_page);
3041 blk_cleanup_queue(q);
3043 free_cpumask_var(mdev->cpu_mask);
3049 /* counterpart of drbd_new_device.
3050 * last part of drbd_delete_device. */
3051 void drbd_free_mdev(struct drbd_conf *mdev)
3053 kfree(mdev->current_epoch);
3054 kfree(mdev->app_reads_hash);
3056 if (mdev->bitmap) /* should no longer be there. */
3057 drbd_bm_cleanup(mdev);
3058 __free_page(mdev->md_io_page);
3059 put_disk(mdev->vdisk);
3060 blk_cleanup_queue(mdev->rq_queue);
3061 free_cpumask_var(mdev->cpu_mask);
3066 int __init drbd_init(void)
3070 if (sizeof(struct p_handshake) != 80) {
3072 "drbd: never change the size or layout "
3073 "of the HandShake packet.\n");
3077 if (1 > minor_count || minor_count > 255) {
3079 "drbd: invalid minor_count (%d)\n", minor_count);
3087 err = drbd_nl_init();
3091 err = register_blkdev(DRBD_MAJOR, "drbd");
3094 "drbd: unable to register block device major %d\n",
3099 register_reboot_notifier(&drbd_notifier);
3102 * allocate all necessary structs
3106 init_waitqueue_head(&drbd_pp_wait);
3108 drbd_proc = NULL; /* play safe for drbd_cleanup */
3109 minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
3114 err = drbd_create_mempools();
3118 drbd_proc = proc_create("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops);
3120 printk(KERN_ERR "drbd: unable to register proc file\n");
3124 rwlock_init(&global_state_lock);
3126 printk(KERN_INFO "drbd: initialized. "
3127 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
3128 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
3129 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
3130 printk(KERN_INFO "drbd: registered as block device major %d\n",
3132 printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
3134 return 0; /* Success! */
3139 /* currently always the case */
3140 printk(KERN_ERR "drbd: ran out of memory\n");
3142 printk(KERN_ERR "drbd: initialization failure\n");
3146 void drbd_free_bc(struct drbd_backing_dev *ldev)
3151 bd_release(ldev->backing_bdev);
3152 bd_release(ldev->md_bdev);
3154 fput(ldev->lo_file);
3155 fput(ldev->md_file);
3160 void drbd_free_sock(struct drbd_conf *mdev)
3162 if (mdev->data.socket) {
3163 kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR);
3164 sock_release(mdev->data.socket);
3165 mdev->data.socket = NULL;
3167 if (mdev->meta.socket) {
3168 kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR);
3169 sock_release(mdev->meta.socket);
3170 mdev->meta.socket = NULL;
3175 void drbd_free_resources(struct drbd_conf *mdev)
3177 crypto_free_hash(mdev->csums_tfm);
3178 mdev->csums_tfm = NULL;
3179 crypto_free_hash(mdev->verify_tfm);
3180 mdev->verify_tfm = NULL;
3181 crypto_free_hash(mdev->cram_hmac_tfm);
3182 mdev->cram_hmac_tfm = NULL;
3183 crypto_free_hash(mdev->integrity_w_tfm);
3184 mdev->integrity_w_tfm = NULL;
3185 crypto_free_hash(mdev->integrity_r_tfm);
3186 mdev->integrity_r_tfm = NULL;
3188 drbd_free_sock(mdev);
3191 drbd_free_bc(mdev->ldev);
3192 mdev->ldev = NULL;);
3195 /* meta data management */
3197 struct meta_data_on_disk {
3198 u64 la_size; /* last agreed size. */
3199 u64 uuid[UI_SIZE]; /* UUIDs. */
3202 u32 flags; /* MDF */
3205 u32 al_offset; /* offset to this block */
3206 u32 al_nr_extents; /* important for restoring the AL */
3207 /* `-- act_log->nr_elements <-- sync_conf.al_extents */
3208 u32 bm_offset; /* offset to the bitmap, from here */
3209 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
3210 u32 reserved_u32[4];
3215 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
3216 * @mdev: DRBD device.
3218 void drbd_md_sync(struct drbd_conf *mdev)
3220 struct meta_data_on_disk *buffer;
3224 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
3226 del_timer(&mdev->md_sync_timer);
3228 /* We use here D_FAILED and not D_ATTACHING because we try to write
3229 * metadata even if we detach due to a disk failure! */
3230 if (!get_ldev_if_state(mdev, D_FAILED))
3233 mutex_lock(&mdev->md_io_mutex);
3234 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3235 memset(buffer, 0, 512);
3237 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
3238 for (i = UI_CURRENT; i < UI_SIZE; i++)
3239 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
3240 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
3241 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
3243 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
3244 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
3245 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
3246 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
3247 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
3249 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
3251 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
3252 sector = mdev->ldev->md.md_offset;
3254 if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
3255 clear_bit(MD_DIRTY, &mdev->flags);
3257 /* this was a try anyways ... */
3258 dev_err(DEV, "meta data update failed!\n");
3260 drbd_chk_io_error(mdev, 1, TRUE);
3263 /* Update mdev->ldev->md.la_size_sect,
3264 * since we updated it on metadata. */
3265 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
3267 mutex_unlock(&mdev->md_io_mutex);
3272 * drbd_md_read() - Reads in the meta data super block
3273 * @mdev: DRBD device.
3274 * @bdev: Device from which the meta data should be read in.
3276 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_codes in case
3277 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
3279 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
3281 struct meta_data_on_disk *buffer;
3282 int i, rv = NO_ERROR;
3284 if (!get_ldev_if_state(mdev, D_ATTACHING))
3285 return ERR_IO_MD_DISK;
3287 mutex_lock(&mdev->md_io_mutex);
3288 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3290 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
3291 /* NOTE: cant do normal error processing here as this is
3292 called BEFORE disk is attached */
3293 dev_err(DEV, "Error while reading metadata.\n");
3294 rv = ERR_IO_MD_DISK;
3298 if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) {
3299 dev_err(DEV, "Error while reading metadata, magic not found.\n");
3300 rv = ERR_MD_INVALID;
3303 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
3304 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
3305 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
3306 rv = ERR_MD_INVALID;
3309 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
3310 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
3311 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
3312 rv = ERR_MD_INVALID;
3315 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
3316 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
3317 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
3318 rv = ERR_MD_INVALID;
3322 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
3323 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
3324 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
3325 rv = ERR_MD_INVALID;
3329 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
3330 for (i = UI_CURRENT; i < UI_SIZE; i++)
3331 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
3332 bdev->md.flags = be32_to_cpu(buffer->flags);
3333 mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents);
3334 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
3336 if (mdev->sync_conf.al_extents < 7)
3337 mdev->sync_conf.al_extents = 127;
3340 mutex_unlock(&mdev->md_io_mutex);
3347 * drbd_md_mark_dirty() - Mark meta data super block as dirty
3348 * @mdev: DRBD device.
3350 * Call this function if you change anything that should be written to
3351 * the meta-data super block. This function sets MD_DIRTY, and starts a
3352 * timer that ensures that within five seconds you have to call drbd_md_sync().
3354 void drbd_md_mark_dirty(struct drbd_conf *mdev)
3356 set_bit(MD_DIRTY, &mdev->flags);
3357 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
3361 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
3365 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
3366 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
3369 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3371 if (idx == UI_CURRENT) {
3372 if (mdev->state.role == R_PRIMARY)
3377 drbd_set_ed_uuid(mdev, val);
3380 mdev->ldev->md.uuid[idx] = val;
3381 drbd_md_mark_dirty(mdev);
3385 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3387 if (mdev->ldev->md.uuid[idx]) {
3388 drbd_uuid_move_history(mdev);
3389 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
3391 _drbd_uuid_set(mdev, idx, val);
3395 * drbd_uuid_new_current() - Creates a new current UUID
3396 * @mdev: DRBD device.
3398 * Creates a new current UUID, and rotates the old current UUID into
3399 * the bitmap slot. Causes an incremental resync upon next connect.
3401 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
3405 dev_info(DEV, "Creating new current UUID\n");
3406 D_ASSERT(mdev->ldev->md.uuid[UI_BITMAP] == 0);
3407 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
3409 get_random_bytes(&val, sizeof(u64));
3410 _drbd_uuid_set(mdev, UI_CURRENT, val);
3413 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
3415 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
3419 drbd_uuid_move_history(mdev);
3420 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
3421 mdev->ldev->md.uuid[UI_BITMAP] = 0;
3423 if (mdev->ldev->md.uuid[UI_BITMAP])
3424 dev_warn(DEV, "bm UUID already set");
3426 mdev->ldev->md.uuid[UI_BITMAP] = val;
3427 mdev->ldev->md.uuid[UI_BITMAP] &= ~((u64)1);
3430 drbd_md_mark_dirty(mdev);
3434 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3435 * @mdev: DRBD device.
3437 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
3439 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
3443 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3444 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
3446 drbd_bm_set_all(mdev);
3448 rv = drbd_bm_write(mdev);
3451 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
3462 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3463 * @mdev: DRBD device.
3465 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
3467 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
3471 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3472 drbd_bm_clear_all(mdev);
3473 rv = drbd_bm_write(mdev);
3480 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3482 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
3485 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
3487 drbd_bm_lock(mdev, work->why);
3488 rv = work->io_fn(mdev);
3489 drbd_bm_unlock(mdev);
3491 clear_bit(BITMAP_IO, &mdev->flags);
3492 wake_up(&mdev->misc_wait);
3495 work->done(mdev, rv);
3497 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
3504 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
3505 * @mdev: DRBD device.
3506 * @io_fn: IO callback to be called when bitmap IO is possible
3507 * @done: callback to be called after the bitmap IO was performed
3508 * @why: Descriptive text of the reason for doing the IO
3510 * While IO on the bitmap happens we freeze application IO thus we ensure
3511 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
3512 * called from worker context. It MUST NOT be used while a previous such
3513 * work is still pending!
3515 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
3516 int (*io_fn)(struct drbd_conf *),
3517 void (*done)(struct drbd_conf *, int),
3520 D_ASSERT(current == mdev->worker.task);
3522 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
3523 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
3524 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
3525 if (mdev->bm_io_work.why)
3526 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
3527 why, mdev->bm_io_work.why);
3529 mdev->bm_io_work.io_fn = io_fn;
3530 mdev->bm_io_work.done = done;
3531 mdev->bm_io_work.why = why;
3533 set_bit(BITMAP_IO, &mdev->flags);
3534 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
3535 if (list_empty(&mdev->bm_io_work.w.list)) {
3536 set_bit(BITMAP_IO_QUEUED, &mdev->flags);
3537 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
3539 dev_err(DEV, "FIXME avoided double queuing bm_io_work\n");
3544 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
3545 * @mdev: DRBD device.
3546 * @io_fn: IO callback to be called when bitmap IO is possible
3547 * @why: Descriptive text of the reason for doing the IO
3549 * freezes application IO while that the actual IO operations runs. This
3550 * functions MAY NOT be called from worker context.
3552 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why)
3556 D_ASSERT(current != mdev->worker.task);
3558 drbd_suspend_io(mdev);
3560 drbd_bm_lock(mdev, why);
3562 drbd_bm_unlock(mdev);
3564 drbd_resume_io(mdev);
3569 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3571 if ((mdev->ldev->md.flags & flag) != flag) {
3572 drbd_md_mark_dirty(mdev);
3573 mdev->ldev->md.flags |= flag;
3577 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3579 if ((mdev->ldev->md.flags & flag) != 0) {
3580 drbd_md_mark_dirty(mdev);
3581 mdev->ldev->md.flags &= ~flag;
3584 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
3586 return (bdev->md.flags & flag) != 0;
3589 static void md_sync_timer_fn(unsigned long data)
3591 struct drbd_conf *mdev = (struct drbd_conf *) data;
3593 drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work);
3596 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3598 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3604 #ifdef CONFIG_DRBD_FAULT_INJECTION
3605 /* Fault insertion support including random number generator shamelessly
3606 * stolen from kernel/rcutorture.c */
3607 struct fault_random_state {
3608 unsigned long state;
3609 unsigned long count;
3612 #define FAULT_RANDOM_MULT 39916801 /* prime */
3613 #define FAULT_RANDOM_ADD 479001701 /* prime */
3614 #define FAULT_RANDOM_REFRESH 10000
3617 * Crude but fast random-number generator. Uses a linear congruential
3618 * generator, with occasional help from get_random_bytes().
3620 static unsigned long
3621 _drbd_fault_random(struct fault_random_state *rsp)
3625 if (!rsp->count--) {
3626 get_random_bytes(&refresh, sizeof(refresh));
3627 rsp->state += refresh;
3628 rsp->count = FAULT_RANDOM_REFRESH;
3630 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
3631 return swahw32(rsp->state);
3635 _drbd_fault_str(unsigned int type) {
3636 static char *_faults[] = {
3637 [DRBD_FAULT_MD_WR] = "Meta-data write",
3638 [DRBD_FAULT_MD_RD] = "Meta-data read",
3639 [DRBD_FAULT_RS_WR] = "Resync write",
3640 [DRBD_FAULT_RS_RD] = "Resync read",
3641 [DRBD_FAULT_DT_WR] = "Data write",
3642 [DRBD_FAULT_DT_RD] = "Data read",
3643 [DRBD_FAULT_DT_RA] = "Data read ahead",
3644 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
3645 [DRBD_FAULT_AL_EE] = "EE allocation"
3648 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
3652 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
3654 static struct fault_random_state rrs = {0, 0};
3656 unsigned int ret = (
3658 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
3659 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
3664 if (printk_ratelimit())
3665 dev_warn(DEV, "***Simulating %s failure\n",
3666 _drbd_fault_str(type));
3673 const char *drbd_buildtag(void)
3675 /* DRBD built from external sources has here a reference to the
3676 git hash of the source code. */
3678 static char buildtag[38] = "\0uilt-in";
3680 if (buildtag[0] == 0) {
3681 #ifdef CONFIG_MODULES
3682 if (THIS_MODULE != NULL)
3683 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
3692 module_init(drbd_init)
3693 module_exit(drbd_cleanup)
3695 EXPORT_SYMBOL(drbd_conn_str);
3696 EXPORT_SYMBOL(drbd_role_str);
3697 EXPORT_SYMBOL(drbd_disk_str);
3698 EXPORT_SYMBOL(drbd_set_st_err_str);