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/autoconf.h>
30 #include <linux/module.h>
31 #include <linux/version.h>
32 #include <linux/drbd.h>
33 #include <asm/uaccess.h>
34 #include <asm/types.h>
36 #include <linux/ctype.h>
37 #include <linux/smp_lock.h>
39 #include <linux/file.h>
40 #include <linux/proc_fs.h>
41 #include <linux/init.h>
43 #include <linux/memcontrol.h>
44 #include <linux/mm_inline.h>
45 #include <linux/slab.h>
46 #include <linux/random.h>
47 #include <linux/reboot.h>
48 #include <linux/notifier.h>
49 #include <linux/kthread.h>
51 #define __KERNEL_SYSCALLS__
52 #include <linux/unistd.h>
53 #include <linux/vmalloc.h>
55 #include <linux/drbd_limits.h>
57 #include "drbd_tracing.h"
58 #include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */
62 struct after_state_chg_work {
66 enum chg_state_flags flags;
67 struct completion *done;
70 int drbdd_init(struct drbd_thread *);
71 int drbd_worker(struct drbd_thread *);
72 int drbd_asender(struct drbd_thread *);
75 static int drbd_open(struct block_device *bdev, fmode_t mode);
76 static int drbd_release(struct gendisk *gd, fmode_t mode);
77 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused);
78 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
79 union drbd_state ns, enum chg_state_flags flags);
80 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused);
81 static void md_sync_timer_fn(unsigned long data);
82 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused);
84 DEFINE_TRACE(drbd_unplug);
85 DEFINE_TRACE(drbd_uuid);
86 DEFINE_TRACE(drbd_ee);
87 DEFINE_TRACE(drbd_packet);
88 DEFINE_TRACE(drbd_md_io);
89 DEFINE_TRACE(drbd_epoch);
90 DEFINE_TRACE(drbd_netlink);
91 DEFINE_TRACE(drbd_actlog);
92 DEFINE_TRACE(drbd_bio);
93 DEFINE_TRACE(_drbd_resync);
94 DEFINE_TRACE(drbd_req);
96 MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, "
97 "Lars Ellenberg <lars@linbit.com>");
98 MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION);
99 MODULE_VERSION(REL_VERSION);
100 MODULE_LICENSE("GPL");
101 MODULE_PARM_DESC(minor_count, "Maximum number of drbd devices (1-255)");
102 MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR);
104 #include <linux/moduleparam.h>
105 /* allow_open_on_secondary */
106 MODULE_PARM_DESC(allow_oos, "DONT USE!");
107 /* thanks to these macros, if compiled into the kernel (not-module),
108 * this becomes the boot parameter drbd.minor_count */
109 module_param(minor_count, uint, 0444);
110 module_param(disable_sendpage, bool, 0644);
111 module_param(allow_oos, bool, 0);
112 module_param(cn_idx, uint, 0444);
113 module_param(proc_details, int, 0644);
115 #ifdef CONFIG_DRBD_FAULT_INJECTION
118 static int fault_count;
120 /* bitmap of enabled faults */
121 module_param(enable_faults, int, 0664);
122 /* fault rate % value - applies to all enabled faults */
123 module_param(fault_rate, int, 0664);
124 /* count of faults inserted */
125 module_param(fault_count, int, 0664);
126 /* bitmap of devices to insert faults on */
127 module_param(fault_devs, int, 0644);
130 /* module parameter, defined */
131 unsigned int minor_count = 32;
132 int disable_sendpage;
134 unsigned int cn_idx = CN_IDX_DRBD;
135 int proc_details; /* Detail level in proc drbd*/
137 /* Module parameter for setting the user mode helper program
138 * to run. Default is /sbin/drbdadm */
139 char usermode_helper[80] = "/sbin/drbdadm";
141 module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644);
143 /* in 2.6.x, our device mapping and config info contains our virtual gendisks
144 * as member "struct gendisk *vdisk;"
146 struct drbd_conf **minor_table;
148 struct kmem_cache *drbd_request_cache;
149 struct kmem_cache *drbd_ee_cache; /* epoch entries */
150 struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */
151 struct kmem_cache *drbd_al_ext_cache; /* activity log extents */
152 mempool_t *drbd_request_mempool;
153 mempool_t *drbd_ee_mempool;
155 /* I do not use a standard mempool, because:
156 1) I want to hand out the pre-allocated objects first.
157 2) I want to be able to interrupt sleeping allocation with a signal.
158 Note: This is a single linked list, the next pointer is the private
159 member of struct page.
161 struct page *drbd_pp_pool;
162 spinlock_t drbd_pp_lock;
164 wait_queue_head_t drbd_pp_wait;
166 DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5);
168 static struct block_device_operations drbd_ops = {
169 .owner = THIS_MODULE,
171 .release = drbd_release,
174 #define ARRY_SIZE(A) (sizeof(A)/sizeof(A[0]))
177 /* When checking with sparse, and this is an inline function, sparse will
178 give tons of false positives. When this is a real functions sparse works.
180 int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
184 atomic_inc(&mdev->local_cnt);
185 io_allowed = (mdev->state.disk >= mins);
187 if (atomic_dec_and_test(&mdev->local_cnt))
188 wake_up(&mdev->misc_wait);
196 * DOC: The transfer log
198 * The transfer log is a single linked list of &struct drbd_tl_epoch objects.
199 * mdev->newest_tle points to the head, mdev->oldest_tle points to the tail
200 * of the list. There is always at least one &struct drbd_tl_epoch object.
202 * Each &struct drbd_tl_epoch has a circular double linked list of requests
205 static int tl_init(struct drbd_conf *mdev)
207 struct drbd_tl_epoch *b;
209 /* during device minor initialization, we may well use GFP_KERNEL */
210 b = kmalloc(sizeof(struct drbd_tl_epoch), GFP_KERNEL);
213 INIT_LIST_HEAD(&b->requests);
214 INIT_LIST_HEAD(&b->w.list);
218 b->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
220 mdev->oldest_tle = b;
221 mdev->newest_tle = b;
222 INIT_LIST_HEAD(&mdev->out_of_sequence_requests);
224 mdev->tl_hash = NULL;
230 static void tl_cleanup(struct drbd_conf *mdev)
232 D_ASSERT(mdev->oldest_tle == mdev->newest_tle);
233 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
234 kfree(mdev->oldest_tle);
235 mdev->oldest_tle = NULL;
236 kfree(mdev->unused_spare_tle);
237 mdev->unused_spare_tle = NULL;
238 kfree(mdev->tl_hash);
239 mdev->tl_hash = NULL;
244 * _tl_add_barrier() - Adds a barrier to the transfer log
245 * @mdev: DRBD device.
246 * @new: Barrier to be added before the current head of the TL.
248 * The caller must hold the req_lock.
250 void _tl_add_barrier(struct drbd_conf *mdev, struct drbd_tl_epoch *new)
252 struct drbd_tl_epoch *newest_before;
254 INIT_LIST_HEAD(&new->requests);
255 INIT_LIST_HEAD(&new->w.list);
256 new->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
260 newest_before = mdev->newest_tle;
261 /* never send a barrier number == 0, because that is special-cased
262 * when using TCQ for our write ordering code */
263 new->br_number = (newest_before->br_number+1) ?: 1;
264 if (mdev->newest_tle != new) {
265 mdev->newest_tle->next = new;
266 mdev->newest_tle = new;
271 * tl_release() - Free or recycle the oldest &struct drbd_tl_epoch object of the TL
272 * @mdev: DRBD device.
273 * @barrier_nr: Expected identifier of the DRBD write barrier packet.
274 * @set_size: Expected number of requests before that barrier.
276 * In case the passed barrier_nr or set_size does not match the oldest
277 * &struct drbd_tl_epoch objects this function will cause a termination
280 void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
281 unsigned int set_size)
283 struct drbd_tl_epoch *b, *nob; /* next old barrier */
284 struct list_head *le, *tle;
285 struct drbd_request *r;
287 spin_lock_irq(&mdev->req_lock);
289 b = mdev->oldest_tle;
291 /* first some paranoia code */
293 dev_err(DEV, "BAD! BarrierAck #%u received, but no epoch in tl!?\n",
297 if (b->br_number != barrier_nr) {
298 dev_err(DEV, "BAD! BarrierAck #%u received, expected #%u!\n",
299 barrier_nr, b->br_number);
302 if (b->n_req != set_size) {
303 dev_err(DEV, "BAD! BarrierAck #%u received with n_req=%u, expected n_req=%u!\n",
304 barrier_nr, set_size, b->n_req);
308 /* Clean up list of requests processed during current epoch */
309 list_for_each_safe(le, tle, &b->requests) {
310 r = list_entry(le, struct drbd_request, tl_requests);
311 _req_mod(r, barrier_acked);
313 /* There could be requests on the list waiting for completion
314 of the write to the local disk. To avoid corruptions of
315 slab's data structures we have to remove the lists head.
317 Also there could have been a barrier ack out of sequence, overtaking
318 the write acks - which would be a bug and violating write ordering.
319 To not deadlock in case we lose connection while such requests are
320 still pending, we need some way to find them for the
321 _req_mode(connection_lost_while_pending).
323 These have been list_move'd to the out_of_sequence_requests list in
324 _req_mod(, barrier_acked) above.
326 list_del_init(&b->requests);
329 if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags)) {
330 _tl_add_barrier(mdev, b);
332 mdev->oldest_tle = nob;
333 /* if nob == NULL b was the only barrier, and becomes the new
334 barrier. Therefore mdev->oldest_tle points already to b */
336 D_ASSERT(nob != NULL);
337 mdev->oldest_tle = nob;
341 spin_unlock_irq(&mdev->req_lock);
342 dec_ap_pending(mdev);
347 spin_unlock_irq(&mdev->req_lock);
348 drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
353 * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL
354 * @mdev: DRBD device.
356 * This is called after the connection to the peer was lost. The storage covered
357 * by the requests on the transfer gets marked as our of sync. Called from the
358 * receiver thread and the worker thread.
360 void tl_clear(struct drbd_conf *mdev)
362 struct drbd_tl_epoch *b, *tmp;
363 struct list_head *le, *tle;
364 struct drbd_request *r;
365 int new_initial_bnr = net_random();
367 spin_lock_irq(&mdev->req_lock);
369 b = mdev->oldest_tle;
371 list_for_each_safe(le, tle, &b->requests) {
372 r = list_entry(le, struct drbd_request, tl_requests);
373 /* It would be nice to complete outside of spinlock.
374 * But this is easier for now. */
375 _req_mod(r, connection_lost_while_pending);
379 /* there could still be requests on that ring list,
380 * in case local io is still pending */
381 list_del(&b->requests);
383 /* dec_ap_pending corresponding to queue_barrier.
384 * the newest barrier may not have been queued yet,
385 * in which case w.cb is still NULL. */
387 dec_ap_pending(mdev);
389 if (b == mdev->newest_tle) {
390 /* recycle, but reinit! */
391 D_ASSERT(tmp == NULL);
392 INIT_LIST_HEAD(&b->requests);
393 INIT_LIST_HEAD(&b->w.list);
395 b->br_number = new_initial_bnr;
398 mdev->oldest_tle = b;
405 /* we expect this list to be empty. */
406 D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
408 /* but just in case, clean it up anyways! */
409 list_for_each_safe(le, tle, &mdev->out_of_sequence_requests) {
410 r = list_entry(le, struct drbd_request, tl_requests);
411 /* It would be nice to complete outside of spinlock.
412 * But this is easier for now. */
413 _req_mod(r, connection_lost_while_pending);
416 /* ensure bit indicating barrier is required is clear */
417 clear_bit(CREATE_BARRIER, &mdev->flags);
419 spin_unlock_irq(&mdev->req_lock);
423 * cl_wide_st_chg() - TRUE if the state change is a cluster wide one
424 * @mdev: DRBD device.
425 * @os: old (current) state.
426 * @ns: new (wanted) state.
428 static int cl_wide_st_chg(struct drbd_conf *mdev,
429 union drbd_state os, union drbd_state ns)
431 return (os.conn >= C_CONNECTED && ns.conn >= C_CONNECTED &&
432 ((os.role != R_PRIMARY && ns.role == R_PRIMARY) ||
433 (os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
434 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S) ||
435 (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))) ||
436 (os.conn >= C_CONNECTED && ns.conn == C_DISCONNECTING) ||
437 (os.conn == C_CONNECTED && ns.conn == C_VERIFY_S);
440 int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f,
441 union drbd_state mask, union drbd_state val)
444 union drbd_state os, ns;
447 spin_lock_irqsave(&mdev->req_lock, flags);
449 ns.i = (os.i & ~mask.i) | val.i;
450 rv = _drbd_set_state(mdev, ns, f, NULL);
452 spin_unlock_irqrestore(&mdev->req_lock, flags);
458 * drbd_force_state() - Impose a change which happens outside our control on our state
459 * @mdev: DRBD device.
460 * @mask: mask of state bits to change.
461 * @val: value of new state bits.
463 void drbd_force_state(struct drbd_conf *mdev,
464 union drbd_state mask, union drbd_state val)
466 drbd_change_state(mdev, CS_HARD, mask, val);
469 static int is_valid_state(struct drbd_conf *mdev, union drbd_state ns);
470 static int is_valid_state_transition(struct drbd_conf *,
471 union drbd_state, union drbd_state);
472 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
473 union drbd_state ns, int *warn_sync_abort);
474 int drbd_send_state_req(struct drbd_conf *,
475 union drbd_state, union drbd_state);
477 static enum drbd_state_ret_codes _req_st_cond(struct drbd_conf *mdev,
478 union drbd_state mask, union drbd_state val)
480 union drbd_state os, ns;
484 if (test_and_clear_bit(CL_ST_CHG_SUCCESS, &mdev->flags))
485 return SS_CW_SUCCESS;
487 if (test_and_clear_bit(CL_ST_CHG_FAIL, &mdev->flags))
488 return SS_CW_FAILED_BY_PEER;
491 spin_lock_irqsave(&mdev->req_lock, flags);
493 ns.i = (os.i & ~mask.i) | val.i;
494 ns = sanitize_state(mdev, os, ns, NULL);
496 if (!cl_wide_st_chg(mdev, os, ns))
499 rv = is_valid_state(mdev, ns);
500 if (rv == SS_SUCCESS) {
501 rv = is_valid_state_transition(mdev, ns, os);
502 if (rv == SS_SUCCESS)
503 rv = 0; /* cont waiting, otherwise fail. */
506 spin_unlock_irqrestore(&mdev->req_lock, flags);
512 * drbd_req_state() - Perform an eventually cluster wide state change
513 * @mdev: DRBD device.
514 * @mask: mask of state bits to change.
515 * @val: value of new state bits.
518 * Should not be called directly, use drbd_request_state() or
519 * _drbd_request_state().
521 static int drbd_req_state(struct drbd_conf *mdev,
522 union drbd_state mask, union drbd_state val,
523 enum chg_state_flags f)
525 struct completion done;
527 union drbd_state os, ns;
530 init_completion(&done);
532 if (f & CS_SERIALIZE)
533 mutex_lock(&mdev->state_mutex);
535 spin_lock_irqsave(&mdev->req_lock, flags);
537 ns.i = (os.i & ~mask.i) | val.i;
538 ns = sanitize_state(mdev, os, ns, NULL);
540 if (cl_wide_st_chg(mdev, os, ns)) {
541 rv = is_valid_state(mdev, ns);
542 if (rv == SS_SUCCESS)
543 rv = is_valid_state_transition(mdev, ns, os);
544 spin_unlock_irqrestore(&mdev->req_lock, flags);
546 if (rv < SS_SUCCESS) {
548 print_st_err(mdev, os, ns, rv);
552 drbd_state_lock(mdev);
553 if (!drbd_send_state_req(mdev, mask, val)) {
554 drbd_state_unlock(mdev);
555 rv = SS_CW_FAILED_BY_PEER;
557 print_st_err(mdev, os, ns, rv);
561 wait_event(mdev->state_wait,
562 (rv = _req_st_cond(mdev, mask, val)));
564 if (rv < SS_SUCCESS) {
565 drbd_state_unlock(mdev);
567 print_st_err(mdev, os, ns, rv);
570 spin_lock_irqsave(&mdev->req_lock, flags);
572 ns.i = (os.i & ~mask.i) | val.i;
573 rv = _drbd_set_state(mdev, ns, f, &done);
574 drbd_state_unlock(mdev);
576 rv = _drbd_set_state(mdev, ns, f, &done);
579 spin_unlock_irqrestore(&mdev->req_lock, flags);
581 if (f & CS_WAIT_COMPLETE && rv == SS_SUCCESS) {
582 D_ASSERT(current != mdev->worker.task);
583 wait_for_completion(&done);
587 if (f & CS_SERIALIZE)
588 mutex_unlock(&mdev->state_mutex);
594 * _drbd_request_state() - Request a state change (with flags)
595 * @mdev: DRBD device.
596 * @mask: mask of state bits to change.
597 * @val: value of new state bits.
600 * Cousin of drbd_request_state(), useful with the CS_WAIT_COMPLETE
601 * flag, or when logging of failed state change requests is not desired.
603 int _drbd_request_state(struct drbd_conf *mdev, union drbd_state mask,
604 union drbd_state val, enum chg_state_flags f)
608 wait_event(mdev->state_wait,
609 (rv = drbd_req_state(mdev, mask, val, f)) != SS_IN_TRANSIENT_STATE);
614 static void print_st(struct drbd_conf *mdev, char *name, union drbd_state ns)
616 dev_err(DEV, " %s = { cs:%s ro:%s/%s ds:%s/%s %c%c%c%c }\n",
618 drbd_conn_str(ns.conn),
619 drbd_role_str(ns.role),
620 drbd_role_str(ns.peer),
621 drbd_disk_str(ns.disk),
622 drbd_disk_str(ns.pdsk),
624 ns.aftr_isp ? 'a' : '-',
625 ns.peer_isp ? 'p' : '-',
626 ns.user_isp ? 'u' : '-'
630 void print_st_err(struct drbd_conf *mdev,
631 union drbd_state os, union drbd_state ns, int err)
633 if (err == SS_IN_TRANSIENT_STATE)
635 dev_err(DEV, "State change failed: %s\n", drbd_set_st_err_str(err));
636 print_st(mdev, " state", os);
637 print_st(mdev, "wanted", ns);
641 #define drbd_peer_str drbd_role_str
642 #define drbd_pdsk_str drbd_disk_str
644 #define drbd_susp_str(A) ((A) ? "1" : "0")
645 #define drbd_aftr_isp_str(A) ((A) ? "1" : "0")
646 #define drbd_peer_isp_str(A) ((A) ? "1" : "0")
647 #define drbd_user_isp_str(A) ((A) ? "1" : "0")
650 ({ if (ns.A != os.A) { \
651 pbp += sprintf(pbp, #A "( %s -> %s ) ", \
652 drbd_##A##_str(os.A), \
653 drbd_##A##_str(ns.A)); \
657 * is_valid_state() - Returns an SS_ error code if ns is not valid
658 * @mdev: DRBD device.
659 * @ns: State to consider.
661 static int is_valid_state(struct drbd_conf *mdev, union drbd_state ns)
663 /* See drbd_state_sw_errors in drbd_strings.c */
665 enum drbd_fencing_p fp;
669 if (get_ldev(mdev)) {
670 fp = mdev->ldev->dc.fencing;
674 if (get_net_conf(mdev)) {
675 if (!mdev->net_conf->two_primaries &&
676 ns.role == R_PRIMARY && ns.peer == R_PRIMARY)
677 rv = SS_TWO_PRIMARIES;
682 /* already found a reason to abort */;
683 else if (ns.role == R_SECONDARY && mdev->open_cnt)
684 rv = SS_DEVICE_IN_USE;
686 else if (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.disk < D_UP_TO_DATE)
687 rv = SS_NO_UP_TO_DATE_DISK;
689 else if (fp >= FP_RESOURCE &&
690 ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk >= D_UNKNOWN)
693 else if (ns.role == R_PRIMARY && ns.disk <= D_INCONSISTENT && ns.pdsk <= D_INCONSISTENT)
694 rv = SS_NO_UP_TO_DATE_DISK;
696 else if (ns.conn > C_CONNECTED && ns.disk < D_INCONSISTENT)
697 rv = SS_NO_LOCAL_DISK;
699 else if (ns.conn > C_CONNECTED && ns.pdsk < D_INCONSISTENT)
700 rv = SS_NO_REMOTE_DISK;
702 else if ((ns.conn == C_CONNECTED ||
703 ns.conn == C_WF_BITMAP_S ||
704 ns.conn == C_SYNC_SOURCE ||
705 ns.conn == C_PAUSED_SYNC_S) &&
706 ns.disk == D_OUTDATED)
707 rv = SS_CONNECTED_OUTDATES;
709 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
710 (mdev->sync_conf.verify_alg[0] == 0))
711 rv = SS_NO_VERIFY_ALG;
713 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
714 mdev->agreed_pro_version < 88)
715 rv = SS_NOT_SUPPORTED;
721 * is_valid_state_transition() - Returns an SS_ error code if the state transition is not possible
722 * @mdev: DRBD device.
726 static int is_valid_state_transition(struct drbd_conf *mdev,
727 union drbd_state ns, union drbd_state os)
731 if ((ns.conn == C_STARTING_SYNC_T || ns.conn == C_STARTING_SYNC_S) &&
732 os.conn > C_CONNECTED)
733 rv = SS_RESYNC_RUNNING;
735 if (ns.conn == C_DISCONNECTING && os.conn == C_STANDALONE)
736 rv = SS_ALREADY_STANDALONE;
738 if (ns.disk > D_ATTACHING && os.disk == D_DISKLESS)
741 if (ns.conn == C_WF_CONNECTION && os.conn < C_UNCONNECTED)
742 rv = SS_NO_NET_CONFIG;
744 if (ns.disk == D_OUTDATED && os.disk < D_OUTDATED && os.disk != D_ATTACHING)
745 rv = SS_LOWER_THAN_OUTDATED;
747 if (ns.conn == C_DISCONNECTING && os.conn == C_UNCONNECTED)
748 rv = SS_IN_TRANSIENT_STATE;
750 if (ns.conn == os.conn && ns.conn == C_WF_REPORT_PARAMS)
751 rv = SS_IN_TRANSIENT_STATE;
753 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && os.conn < C_CONNECTED)
754 rv = SS_NEED_CONNECTION;
756 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
757 ns.conn != os.conn && os.conn > C_CONNECTED)
758 rv = SS_RESYNC_RUNNING;
760 if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) &&
761 os.conn < C_CONNECTED)
762 rv = SS_NEED_CONNECTION;
768 * sanitize_state() - Resolves implicitly necessary additional changes to a state transition
769 * @mdev: DRBD device.
774 * When we loose connection, we have to set the state of the peers disk (pdsk)
775 * to D_UNKNOWN. This rule and many more along those lines are in this function.
777 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
778 union drbd_state ns, int *warn_sync_abort)
780 enum drbd_fencing_p fp;
783 if (get_ldev(mdev)) {
784 fp = mdev->ldev->dc.fencing;
788 /* Disallow Network errors to configure a device's network part */
789 if ((ns.conn >= C_TIMEOUT && ns.conn <= C_TEAR_DOWN) &&
790 os.conn <= C_DISCONNECTING)
793 /* After a network error (+C_TEAR_DOWN) only C_UNCONNECTED or C_DISCONNECTING can follow */
794 if (os.conn >= C_TIMEOUT && os.conn <= C_TEAR_DOWN &&
795 ns.conn != C_UNCONNECTED && ns.conn != C_DISCONNECTING)
798 /* After C_DISCONNECTING only C_STANDALONE may follow */
799 if (os.conn == C_DISCONNECTING && ns.conn != C_STANDALONE)
802 if (ns.conn < C_CONNECTED) {
805 if (ns.pdsk > D_UNKNOWN || ns.pdsk < D_INCONSISTENT)
809 /* Clear the aftr_isp when becoming unconfigured */
810 if (ns.conn == C_STANDALONE && ns.disk == D_DISKLESS && ns.role == R_SECONDARY)
813 if (ns.conn <= C_DISCONNECTING && ns.disk == D_DISKLESS)
816 /* Abort resync if a disk fails/detaches */
817 if (os.conn > C_CONNECTED && ns.conn > C_CONNECTED &&
818 (ns.disk <= D_FAILED || ns.pdsk <= D_FAILED)) {
820 *warn_sync_abort = 1;
821 ns.conn = C_CONNECTED;
824 if (ns.conn >= C_CONNECTED &&
825 ((ns.disk == D_CONSISTENT || ns.disk == D_OUTDATED) ||
826 (ns.disk == D_NEGOTIATING && ns.conn == C_WF_BITMAP_T))) {
829 case C_PAUSED_SYNC_T:
830 ns.disk = D_OUTDATED;
835 case C_PAUSED_SYNC_S:
836 ns.disk = D_UP_TO_DATE;
839 ns.disk = D_INCONSISTENT;
840 dev_warn(DEV, "Implicitly set disk state Inconsistent!\n");
843 if (os.disk == D_OUTDATED && ns.disk == D_UP_TO_DATE)
844 dev_warn(DEV, "Implicitly set disk from Outdated to UpToDate\n");
847 if (ns.conn >= C_CONNECTED &&
848 (ns.pdsk == D_CONSISTENT || ns.pdsk == D_OUTDATED)) {
852 case C_PAUSED_SYNC_T:
854 ns.pdsk = D_UP_TO_DATE;
857 case C_PAUSED_SYNC_S:
858 ns.pdsk = D_OUTDATED;
861 ns.pdsk = D_INCONSISTENT;
862 dev_warn(DEV, "Implicitly set pdsk Inconsistent!\n");
865 if (os.pdsk == D_OUTDATED && ns.pdsk == D_UP_TO_DATE)
866 dev_warn(DEV, "Implicitly set pdsk from Outdated to UpToDate\n");
869 /* Connection breaks down before we finished "Negotiating" */
870 if (ns.conn < C_CONNECTED && ns.disk == D_NEGOTIATING &&
871 get_ldev_if_state(mdev, D_NEGOTIATING)) {
872 if (mdev->ed_uuid == mdev->ldev->md.uuid[UI_CURRENT]) {
873 ns.disk = mdev->new_state_tmp.disk;
874 ns.pdsk = mdev->new_state_tmp.pdsk;
876 dev_alert(DEV, "Connection lost while negotiating, no data!\n");
877 ns.disk = D_DISKLESS;
883 if (fp == FP_STONITH &&
884 (ns.role == R_PRIMARY &&
885 ns.conn < C_CONNECTED &&
886 ns.pdsk > D_OUTDATED))
889 if (ns.aftr_isp || ns.peer_isp || ns.user_isp) {
890 if (ns.conn == C_SYNC_SOURCE)
891 ns.conn = C_PAUSED_SYNC_S;
892 if (ns.conn == C_SYNC_TARGET)
893 ns.conn = C_PAUSED_SYNC_T;
895 if (ns.conn == C_PAUSED_SYNC_S)
896 ns.conn = C_SYNC_SOURCE;
897 if (ns.conn == C_PAUSED_SYNC_T)
898 ns.conn = C_SYNC_TARGET;
904 /* helper for __drbd_set_state */
905 static void set_ov_position(struct drbd_conf *mdev, enum drbd_conns cs)
907 if (cs == C_VERIFY_T) {
908 /* starting online verify from an arbitrary position
909 * does not fit well into the existing protocol.
910 * on C_VERIFY_T, we initialize ov_left and friends
911 * implicitly in receive_DataRequest once the
912 * first P_OV_REQUEST is received */
913 mdev->ov_start_sector = ~(sector_t)0;
915 unsigned long bit = BM_SECT_TO_BIT(mdev->ov_start_sector);
916 if (bit >= mdev->rs_total)
917 mdev->ov_start_sector =
918 BM_BIT_TO_SECT(mdev->rs_total - 1);
919 mdev->ov_position = mdev->ov_start_sector;
924 * __drbd_set_state() - Set a new DRBD state
925 * @mdev: DRBD device.
928 * @done: Optional completion, that will get completed after the after_state_ch() finished
930 * Caller needs to hold req_lock, and global_state_lock. Do not call directly.
932 int __drbd_set_state(struct drbd_conf *mdev,
933 union drbd_state ns, enum chg_state_flags flags,
934 struct completion *done)
938 int warn_sync_abort = 0;
939 struct after_state_chg_work *ascw;
943 ns = sanitize_state(mdev, os, ns, &warn_sync_abort);
946 return SS_NOTHING_TO_DO;
948 if (!(flags & CS_HARD)) {
949 /* pre-state-change checks ; only look at ns */
950 /* See drbd_state_sw_errors in drbd_strings.c */
952 rv = is_valid_state(mdev, ns);
953 if (rv < SS_SUCCESS) {
954 /* If the old state was illegal as well, then let
957 if (is_valid_state(mdev, os) == rv) {
958 dev_err(DEV, "Considering state change from bad state. "
959 "Error would be: '%s'\n",
960 drbd_set_st_err_str(rv));
961 print_st(mdev, "old", os);
962 print_st(mdev, "new", ns);
963 rv = is_valid_state_transition(mdev, ns, os);
966 rv = is_valid_state_transition(mdev, ns, os);
969 if (rv < SS_SUCCESS) {
970 if (flags & CS_VERBOSE)
971 print_st_err(mdev, os, ns, rv);
976 dev_warn(DEV, "Resync aborted.\n");
991 dev_info(DEV, "%s\n", pb);
994 /* solve the race between becoming unconfigured,
995 * worker doing the cleanup, and
996 * admin reconfiguring us:
997 * on (re)configure, first set CONFIG_PENDING,
998 * then wait for a potentially exiting worker,
999 * start the worker, and schedule one no_op.
1000 * then proceed with configuration.
1002 if (ns.disk == D_DISKLESS &&
1003 ns.conn == C_STANDALONE &&
1004 ns.role == R_SECONDARY &&
1005 !test_and_set_bit(CONFIG_PENDING, &mdev->flags))
1006 set_bit(DEVICE_DYING, &mdev->flags);
1008 mdev->state.i = ns.i;
1009 wake_up(&mdev->misc_wait);
1010 wake_up(&mdev->state_wait);
1012 /* post-state-change actions */
1013 if (os.conn >= C_SYNC_SOURCE && ns.conn <= C_CONNECTED) {
1014 set_bit(STOP_SYNC_TIMER, &mdev->flags);
1015 mod_timer(&mdev->resync_timer, jiffies);
1018 /* aborted verify run. log the last position */
1019 if ((os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) &&
1020 ns.conn < C_CONNECTED) {
1021 mdev->ov_start_sector =
1022 BM_BIT_TO_SECT(mdev->rs_total - mdev->ov_left);
1023 dev_info(DEV, "Online Verify reached sector %llu\n",
1024 (unsigned long long)mdev->ov_start_sector);
1027 if ((os.conn == C_PAUSED_SYNC_T || os.conn == C_PAUSED_SYNC_S) &&
1028 (ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)) {
1029 dev_info(DEV, "Syncer continues.\n");
1030 mdev->rs_paused += (long)jiffies-(long)mdev->rs_mark_time;
1031 if (ns.conn == C_SYNC_TARGET) {
1032 if (!test_and_clear_bit(STOP_SYNC_TIMER, &mdev->flags))
1033 mod_timer(&mdev->resync_timer, jiffies);
1034 /* This if (!test_bit) is only needed for the case
1035 that a device that has ceased to used its timer,
1036 i.e. it is already in drbd_resync_finished() gets
1037 paused and resumed. */
1041 if ((os.conn == C_SYNC_TARGET || os.conn == C_SYNC_SOURCE) &&
1042 (ns.conn == C_PAUSED_SYNC_T || ns.conn == C_PAUSED_SYNC_S)) {
1043 dev_info(DEV, "Resync suspended\n");
1044 mdev->rs_mark_time = jiffies;
1045 if (ns.conn == C_PAUSED_SYNC_T)
1046 set_bit(STOP_SYNC_TIMER, &mdev->flags);
1049 if (os.conn == C_CONNECTED &&
1050 (ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T)) {
1051 mdev->ov_position = 0;
1053 mdev->rs_mark_left = drbd_bm_bits(mdev);
1054 if (mdev->agreed_pro_version >= 90)
1055 set_ov_position(mdev, ns.conn);
1057 mdev->ov_start_sector = 0;
1058 mdev->ov_left = mdev->rs_total
1059 - BM_SECT_TO_BIT(mdev->ov_position);
1061 mdev->rs_mark_time = jiffies;
1062 mdev->ov_last_oos_size = 0;
1063 mdev->ov_last_oos_start = 0;
1065 if (ns.conn == C_VERIFY_S) {
1066 dev_info(DEV, "Starting Online Verify from sector %llu\n",
1067 (unsigned long long)mdev->ov_position);
1068 mod_timer(&mdev->resync_timer, jiffies);
1072 if (get_ldev(mdev)) {
1073 u32 mdf = mdev->ldev->md.flags & ~(MDF_CONSISTENT|MDF_PRIMARY_IND|
1074 MDF_CONNECTED_IND|MDF_WAS_UP_TO_DATE|
1075 MDF_PEER_OUT_DATED|MDF_CRASHED_PRIMARY);
1077 if (test_bit(CRASHED_PRIMARY, &mdev->flags))
1078 mdf |= MDF_CRASHED_PRIMARY;
1079 if (mdev->state.role == R_PRIMARY ||
1080 (mdev->state.pdsk < D_INCONSISTENT && mdev->state.peer == R_PRIMARY))
1081 mdf |= MDF_PRIMARY_IND;
1082 if (mdev->state.conn > C_WF_REPORT_PARAMS)
1083 mdf |= MDF_CONNECTED_IND;
1084 if (mdev->state.disk > D_INCONSISTENT)
1085 mdf |= MDF_CONSISTENT;
1086 if (mdev->state.disk > D_OUTDATED)
1087 mdf |= MDF_WAS_UP_TO_DATE;
1088 if (mdev->state.pdsk <= D_OUTDATED && mdev->state.pdsk >= D_INCONSISTENT)
1089 mdf |= MDF_PEER_OUT_DATED;
1090 if (mdf != mdev->ldev->md.flags) {
1091 mdev->ldev->md.flags = mdf;
1092 drbd_md_mark_dirty(mdev);
1094 if (os.disk < D_CONSISTENT && ns.disk >= D_CONSISTENT)
1095 drbd_set_ed_uuid(mdev, mdev->ldev->md.uuid[UI_CURRENT]);
1099 /* Peer was forced D_UP_TO_DATE & R_PRIMARY, consider to resync */
1100 if (os.disk == D_INCONSISTENT && os.pdsk == D_INCONSISTENT &&
1101 os.peer == R_SECONDARY && ns.peer == R_PRIMARY)
1102 set_bit(CONSIDER_RESYNC, &mdev->flags);
1104 /* Receiver should clean up itself */
1105 if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING)
1106 drbd_thread_stop_nowait(&mdev->receiver);
1108 /* Now the receiver finished cleaning up itself, it should die */
1109 if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE)
1110 drbd_thread_stop_nowait(&mdev->receiver);
1112 /* Upon network failure, we need to restart the receiver. */
1113 if (os.conn > C_TEAR_DOWN &&
1114 ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT)
1115 drbd_thread_restart_nowait(&mdev->receiver);
1117 ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC);
1121 ascw->flags = flags;
1122 ascw->w.cb = w_after_state_ch;
1124 drbd_queue_work(&mdev->data.work, &ascw->w);
1126 dev_warn(DEV, "Could not kmalloc an ascw\n");
1132 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused)
1134 struct after_state_chg_work *ascw =
1135 container_of(w, struct after_state_chg_work, w);
1136 after_state_ch(mdev, ascw->os, ascw->ns, ascw->flags);
1137 if (ascw->flags & CS_WAIT_COMPLETE) {
1138 D_ASSERT(ascw->done != NULL);
1139 complete(ascw->done);
1146 static void abw_start_sync(struct drbd_conf *mdev, int rv)
1149 dev_err(DEV, "Writing the bitmap failed not starting resync.\n");
1150 _drbd_request_state(mdev, NS(conn, C_CONNECTED), CS_VERBOSE);
1154 switch (mdev->state.conn) {
1155 case C_STARTING_SYNC_T:
1156 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE);
1158 case C_STARTING_SYNC_S:
1159 drbd_start_resync(mdev, C_SYNC_SOURCE);
1165 * after_state_ch() - Perform after state change actions that may sleep
1166 * @mdev: DRBD device.
1171 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
1172 union drbd_state ns, enum chg_state_flags flags)
1174 enum drbd_fencing_p fp;
1176 if (os.conn != C_CONNECTED && ns.conn == C_CONNECTED) {
1177 clear_bit(CRASHED_PRIMARY, &mdev->flags);
1179 mdev->p_uuid[UI_FLAGS] &= ~((u64)2);
1183 if (get_ldev(mdev)) {
1184 fp = mdev->ldev->dc.fencing;
1188 /* Inform userspace about the change... */
1189 drbd_bcast_state(mdev, ns);
1191 if (!(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE) &&
1192 (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE))
1193 drbd_khelper(mdev, "pri-on-incon-degr");
1195 /* Here we have the actions that are performed after a
1196 state change. This function might sleep */
1198 if (fp == FP_STONITH && ns.susp) {
1199 /* case1: The outdate peer handler is successful:
1200 * case2: The connection was established again: */
1201 if ((os.pdsk > D_OUTDATED && ns.pdsk <= D_OUTDATED) ||
1202 (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)) {
1204 spin_lock_irq(&mdev->req_lock);
1205 _drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL);
1206 spin_unlock_irq(&mdev->req_lock);
1209 /* Do not change the order of the if above and the two below... */
1210 if (os.pdsk == D_DISKLESS && ns.pdsk > D_DISKLESS) { /* attach on the peer */
1211 drbd_send_uuids(mdev);
1212 drbd_send_state(mdev);
1214 if (os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S)
1215 drbd_queue_bitmap_io(mdev, &drbd_send_bitmap, NULL, "send_bitmap (WFBitMapS)");
1217 /* Lost contact to peer's copy of the data */
1218 if ((os.pdsk >= D_INCONSISTENT &&
1219 os.pdsk != D_UNKNOWN &&
1220 os.pdsk != D_OUTDATED)
1221 && (ns.pdsk < D_INCONSISTENT ||
1222 ns.pdsk == D_UNKNOWN ||
1223 ns.pdsk == D_OUTDATED)) {
1224 kfree(mdev->p_uuid);
1225 mdev->p_uuid = NULL;
1226 if (get_ldev(mdev)) {
1227 if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) &&
1228 mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) {
1229 drbd_uuid_new_current(mdev);
1230 drbd_send_uuids(mdev);
1236 if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) {
1237 if (ns.peer == R_PRIMARY && mdev->ldev->md.uuid[UI_BITMAP] == 0)
1238 drbd_uuid_new_current(mdev);
1240 /* D_DISKLESS Peer becomes secondary */
1241 if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
1242 drbd_al_to_on_disk_bm(mdev);
1246 /* Last part of the attaching process ... */
1247 if (ns.conn >= C_CONNECTED &&
1248 os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
1249 kfree(mdev->p_uuid); /* We expect to receive up-to-date UUIDs soon. */
1250 mdev->p_uuid = NULL; /* ...to not use the old ones in the mean time */
1251 drbd_send_sizes(mdev, 0); /* to start sync... */
1252 drbd_send_uuids(mdev);
1253 drbd_send_state(mdev);
1256 /* We want to pause/continue resync, tell peer. */
1257 if (ns.conn >= C_CONNECTED &&
1258 ((os.aftr_isp != ns.aftr_isp) ||
1259 (os.user_isp != ns.user_isp)))
1260 drbd_send_state(mdev);
1262 /* In case one of the isp bits got set, suspend other devices. */
1263 if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
1264 (ns.aftr_isp || ns.peer_isp || ns.user_isp))
1265 suspend_other_sg(mdev);
1267 /* Make sure the peer gets informed about eventual state
1268 changes (ISP bits) while we were in WFReportParams. */
1269 if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
1270 drbd_send_state(mdev);
1272 /* We are in the progress to start a full sync... */
1273 if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
1274 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S))
1275 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, &abw_start_sync, "set_n_write from StartingSync");
1277 /* We are invalidating our self... */
1278 if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED &&
1279 os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT)
1280 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL, "set_n_write from invalidate");
1282 if (os.disk > D_FAILED && ns.disk == D_FAILED) {
1283 enum drbd_io_error_p eh;
1286 if (get_ldev_if_state(mdev, D_FAILED)) {
1287 eh = mdev->ldev->dc.on_io_error;
1291 drbd_rs_cancel_all(mdev);
1292 /* since get_ldev() only works as long as disk>=D_INCONSISTENT,
1293 and it is D_DISKLESS here, local_cnt can only go down, it can
1294 not increase... It will reach zero */
1295 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1297 mdev->rs_failed = 0;
1298 atomic_set(&mdev->rs_pending_cnt, 0);
1300 spin_lock_irq(&mdev->req_lock);
1301 _drbd_set_state(_NS(mdev, disk, D_DISKLESS), CS_HARD, NULL);
1302 spin_unlock_irq(&mdev->req_lock);
1304 if (eh == EP_CALL_HELPER)
1305 drbd_khelper(mdev, "local-io-error");
1308 if (os.disk > D_DISKLESS && ns.disk == D_DISKLESS) {
1310 if (os.disk == D_FAILED) /* && ns.disk == D_DISKLESS*/ {
1311 if (drbd_send_state(mdev))
1312 dev_warn(DEV, "Notified peer that my disk is broken.\n");
1314 dev_err(DEV, "Sending state in drbd_io_error() failed\n");
1317 lc_destroy(mdev->resync);
1318 mdev->resync = NULL;
1319 lc_destroy(mdev->act_log);
1320 mdev->act_log = NULL;
1322 drbd_free_bc(mdev->ldev);
1323 mdev->ldev = NULL;);
1325 if (mdev->md_io_tmpp)
1326 __free_page(mdev->md_io_tmpp);
1329 /* Disks got bigger while they were detached */
1330 if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
1331 test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) {
1332 if (ns.conn == C_CONNECTED)
1333 resync_after_online_grow(mdev);
1336 /* A resync finished or aborted, wake paused devices... */
1337 if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) ||
1338 (os.peer_isp && !ns.peer_isp) ||
1339 (os.user_isp && !ns.user_isp))
1340 resume_next_sg(mdev);
1342 /* Upon network connection, we need to start the receiver */
1343 if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED)
1344 drbd_thread_start(&mdev->receiver);
1346 /* Terminate worker thread if we are unconfigured - it will be
1347 restarted as needed... */
1348 if (ns.disk == D_DISKLESS &&
1349 ns.conn == C_STANDALONE &&
1350 ns.role == R_SECONDARY) {
1351 if (os.aftr_isp != ns.aftr_isp)
1352 resume_next_sg(mdev);
1353 /* set in __drbd_set_state, unless CONFIG_PENDING was set */
1354 if (test_bit(DEVICE_DYING, &mdev->flags))
1355 drbd_thread_stop_nowait(&mdev->worker);
1362 static int drbd_thread_setup(void *arg)
1364 struct drbd_thread *thi = (struct drbd_thread *) arg;
1365 struct drbd_conf *mdev = thi->mdev;
1366 unsigned long flags;
1370 retval = thi->function(thi);
1372 spin_lock_irqsave(&thi->t_lock, flags);
1374 /* if the receiver has been "Exiting", the last thing it did
1375 * was set the conn state to "StandAlone",
1376 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
1377 * and receiver thread will be "started".
1378 * drbd_thread_start needs to set "Restarting" in that case.
1379 * t_state check and assignment needs to be within the same spinlock,
1380 * so either thread_start sees Exiting, and can remap to Restarting,
1381 * or thread_start see None, and can proceed as normal.
1384 if (thi->t_state == Restarting) {
1385 dev_info(DEV, "Restarting %s\n", current->comm);
1386 thi->t_state = Running;
1387 spin_unlock_irqrestore(&thi->t_lock, flags);
1392 thi->t_state = None;
1394 complete(&thi->stop);
1395 spin_unlock_irqrestore(&thi->t_lock, flags);
1397 dev_info(DEV, "Terminating %s\n", current->comm);
1399 /* Release mod reference taken when thread was started */
1400 module_put(THIS_MODULE);
1404 static void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi,
1405 int (*func) (struct drbd_thread *))
1407 spin_lock_init(&thi->t_lock);
1409 thi->t_state = None;
1410 thi->function = func;
1414 int drbd_thread_start(struct drbd_thread *thi)
1416 struct drbd_conf *mdev = thi->mdev;
1417 struct task_struct *nt;
1418 unsigned long flags;
1421 thi == &mdev->receiver ? "receiver" :
1422 thi == &mdev->asender ? "asender" :
1423 thi == &mdev->worker ? "worker" : "NONSENSE";
1425 /* is used from state engine doing drbd_thread_stop_nowait,
1426 * while holding the req lock irqsave */
1427 spin_lock_irqsave(&thi->t_lock, flags);
1429 switch (thi->t_state) {
1431 dev_info(DEV, "Starting %s thread (from %s [%d])\n",
1432 me, current->comm, current->pid);
1434 /* Get ref on module for thread - this is released when thread exits */
1435 if (!try_module_get(THIS_MODULE)) {
1436 dev_err(DEV, "Failed to get module reference in drbd_thread_start\n");
1437 spin_unlock_irqrestore(&thi->t_lock, flags);
1441 init_completion(&thi->stop);
1442 D_ASSERT(thi->task == NULL);
1443 thi->reset_cpu_mask = 1;
1444 thi->t_state = Running;
1445 spin_unlock_irqrestore(&thi->t_lock, flags);
1446 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
1448 nt = kthread_create(drbd_thread_setup, (void *) thi,
1449 "drbd%d_%s", mdev_to_minor(mdev), me);
1452 dev_err(DEV, "Couldn't start thread\n");
1454 module_put(THIS_MODULE);
1457 spin_lock_irqsave(&thi->t_lock, flags);
1459 thi->t_state = Running;
1460 spin_unlock_irqrestore(&thi->t_lock, flags);
1461 wake_up_process(nt);
1464 thi->t_state = Restarting;
1465 dev_info(DEV, "Restarting %s thread (from %s [%d])\n",
1466 me, current->comm, current->pid);
1471 spin_unlock_irqrestore(&thi->t_lock, flags);
1479 void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
1481 unsigned long flags;
1483 enum drbd_thread_state ns = restart ? Restarting : Exiting;
1485 /* may be called from state engine, holding the req lock irqsave */
1486 spin_lock_irqsave(&thi->t_lock, flags);
1488 if (thi->t_state == None) {
1489 spin_unlock_irqrestore(&thi->t_lock, flags);
1491 drbd_thread_start(thi);
1495 if (thi->t_state != ns) {
1496 if (thi->task == NULL) {
1497 spin_unlock_irqrestore(&thi->t_lock, flags);
1503 init_completion(&thi->stop);
1504 if (thi->task != current)
1505 force_sig(DRBD_SIGKILL, thi->task);
1509 spin_unlock_irqrestore(&thi->t_lock, flags);
1512 wait_for_completion(&thi->stop);
1517 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
1518 * @mdev: DRBD device.
1520 * Forces all threads of a device onto the same CPU. This is beneficial for
1521 * DRBD's performance. May be overwritten by user's configuration.
1523 void drbd_calc_cpu_mask(struct drbd_conf *mdev)
1527 /* user override. */
1528 if (cpumask_weight(mdev->cpu_mask))
1531 ord = mdev_to_minor(mdev) % cpumask_weight(cpu_online_mask);
1532 for_each_online_cpu(cpu) {
1534 cpumask_set_cpu(cpu, mdev->cpu_mask);
1538 /* should not be reached */
1539 cpumask_setall(mdev->cpu_mask);
1543 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
1544 * @mdev: DRBD device.
1546 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
1549 void drbd_thread_current_set_cpu(struct drbd_conf *mdev)
1551 struct task_struct *p = current;
1552 struct drbd_thread *thi =
1553 p == mdev->asender.task ? &mdev->asender :
1554 p == mdev->receiver.task ? &mdev->receiver :
1555 p == mdev->worker.task ? &mdev->worker :
1559 if (!thi->reset_cpu_mask)
1561 thi->reset_cpu_mask = 0;
1562 set_cpus_allowed_ptr(p, mdev->cpu_mask);
1566 /* the appropriate socket mutex must be held already */
1567 int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1568 enum drbd_packets cmd, struct p_header *h,
1569 size_t size, unsigned msg_flags)
1573 ERR_IF(!h) return FALSE;
1574 ERR_IF(!size) return FALSE;
1576 h->magic = BE_DRBD_MAGIC;
1577 h->command = cpu_to_be16(cmd);
1578 h->length = cpu_to_be16(size-sizeof(struct p_header));
1580 trace_drbd_packet(mdev, sock, 0, (void *)h, __FILE__, __LINE__);
1581 sent = drbd_send(mdev, sock, h, size, msg_flags);
1583 ok = (sent == size);
1585 dev_err(DEV, "short sent %s size=%d sent=%d\n",
1586 cmdname(cmd), (int)size, sent);
1590 /* don't pass the socket. we may only look at it
1591 * when we hold the appropriate socket mutex.
1593 int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1594 enum drbd_packets cmd, struct p_header *h, size_t size)
1597 struct socket *sock;
1599 if (use_data_socket) {
1600 mutex_lock(&mdev->data.mutex);
1601 sock = mdev->data.socket;
1603 mutex_lock(&mdev->meta.mutex);
1604 sock = mdev->meta.socket;
1607 /* drbd_disconnect() could have called drbd_free_sock()
1608 * while we were waiting in down()... */
1609 if (likely(sock != NULL))
1610 ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0);
1612 if (use_data_socket)
1613 mutex_unlock(&mdev->data.mutex);
1615 mutex_unlock(&mdev->meta.mutex);
1619 int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
1625 h.magic = BE_DRBD_MAGIC;
1626 h.command = cpu_to_be16(cmd);
1627 h.length = cpu_to_be16(size);
1629 if (!drbd_get_data_sock(mdev))
1632 trace_drbd_packet(mdev, mdev->data.socket, 0, (void *)&h, __FILE__, __LINE__);
1635 drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0));
1637 drbd_send(mdev, mdev->data.socket, data, size, 0));
1639 drbd_put_data_sock(mdev);
1644 int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc)
1646 struct p_rs_param_89 *p;
1647 struct socket *sock;
1649 const int apv = mdev->agreed_pro_version;
1651 size = apv <= 87 ? sizeof(struct p_rs_param)
1652 : apv == 88 ? sizeof(struct p_rs_param)
1653 + strlen(mdev->sync_conf.verify_alg) + 1
1654 : /* 89 */ sizeof(struct p_rs_param_89);
1656 /* used from admin command context and receiver/worker context.
1657 * to avoid kmalloc, grab the socket right here,
1658 * then use the pre-allocated sbuf there */
1659 mutex_lock(&mdev->data.mutex);
1660 sock = mdev->data.socket;
1662 if (likely(sock != NULL)) {
1663 enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
1665 p = &mdev->data.sbuf.rs_param_89;
1667 /* initialize verify_alg and csums_alg */
1668 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
1670 p->rate = cpu_to_be32(sc->rate);
1673 strcpy(p->verify_alg, mdev->sync_conf.verify_alg);
1675 strcpy(p->csums_alg, mdev->sync_conf.csums_alg);
1677 rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
1679 rv = 0; /* not ok */
1681 mutex_unlock(&mdev->data.mutex);
1686 int drbd_send_protocol(struct drbd_conf *mdev)
1688 struct p_protocol *p;
1691 size = sizeof(struct p_protocol);
1693 if (mdev->agreed_pro_version >= 87)
1694 size += strlen(mdev->net_conf->integrity_alg) + 1;
1696 /* we must not recurse into our own queue,
1697 * as that is blocked during handshake */
1698 p = kmalloc(size, GFP_NOIO);
1702 p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol);
1703 p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p);
1704 p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p);
1705 p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p);
1706 p->want_lose = cpu_to_be32(mdev->net_conf->want_lose);
1707 p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries);
1709 if (mdev->agreed_pro_version >= 87)
1710 strcpy(p->integrity_alg, mdev->net_conf->integrity_alg);
1712 rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL,
1713 (struct p_header *)p, size);
1718 int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
1723 if (!get_ldev_if_state(mdev, D_NEGOTIATING))
1726 for (i = UI_CURRENT; i < UI_SIZE; i++)
1727 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
1729 mdev->comm_bm_set = drbd_bm_total_weight(mdev);
1730 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
1731 uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
1732 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
1733 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
1734 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
1738 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS,
1739 (struct p_header *)&p, sizeof(p));
1742 int drbd_send_uuids(struct drbd_conf *mdev)
1744 return _drbd_send_uuids(mdev, 0);
1747 int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
1749 return _drbd_send_uuids(mdev, 8);
1753 int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val)
1757 p.uuid = cpu_to_be64(val);
1759 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID,
1760 (struct p_header *)&p, sizeof(p));
1763 int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply)
1766 sector_t d_size, u_size;
1770 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
1771 D_ASSERT(mdev->ldev->backing_bdev);
1772 d_size = drbd_get_max_capacity(mdev->ldev);
1773 u_size = mdev->ldev->dc.disk_size;
1774 q_order_type = drbd_queue_order_type(mdev);
1775 p.queue_order_type = cpu_to_be32(drbd_queue_order_type(mdev));
1780 q_order_type = QUEUE_ORDERED_NONE;
1783 p.d_size = cpu_to_be64(d_size);
1784 p.u_size = cpu_to_be64(u_size);
1785 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
1786 p.max_segment_size = cpu_to_be32(queue_max_segment_size(mdev->rq_queue));
1787 p.queue_order_type = cpu_to_be32(q_order_type);
1789 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES,
1790 (struct p_header *)&p, sizeof(p));
1795 * drbd_send_state() - Sends the drbd state to the peer
1796 * @mdev: DRBD device.
1798 int drbd_send_state(struct drbd_conf *mdev)
1800 struct socket *sock;
1804 /* Grab state lock so we wont send state if we're in the middle
1805 * of a cluster wide state change on another thread */
1806 drbd_state_lock(mdev);
1808 mutex_lock(&mdev->data.mutex);
1810 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
1811 sock = mdev->data.socket;
1813 if (likely(sock != NULL)) {
1814 ok = _drbd_send_cmd(mdev, sock, P_STATE,
1815 (struct p_header *)&p, sizeof(p), 0);
1818 mutex_unlock(&mdev->data.mutex);
1820 drbd_state_unlock(mdev);
1824 int drbd_send_state_req(struct drbd_conf *mdev,
1825 union drbd_state mask, union drbd_state val)
1827 struct p_req_state p;
1829 p.mask = cpu_to_be32(mask.i);
1830 p.val = cpu_to_be32(val.i);
1832 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ,
1833 (struct p_header *)&p, sizeof(p));
1836 int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode)
1838 struct p_req_state_reply p;
1840 p.retcode = cpu_to_be32(retcode);
1842 return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY,
1843 (struct p_header *)&p, sizeof(p));
1846 int fill_bitmap_rle_bits(struct drbd_conf *mdev,
1847 struct p_compressed_bm *p,
1848 struct bm_xfer_ctx *c)
1850 struct bitstream bs;
1851 unsigned long plain_bits;
1858 /* may we use this feature? */
1859 if ((mdev->sync_conf.use_rle == 0) ||
1860 (mdev->agreed_pro_version < 90))
1863 if (c->bit_offset >= c->bm_bits)
1864 return 0; /* nothing to do. */
1866 /* use at most thus many bytes */
1867 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
1868 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
1869 /* plain bits covered in this code string */
1872 /* p->encoding & 0x80 stores whether the first run length is set.
1873 * bit offset is implicit.
1874 * start with toggle == 2 to be able to tell the first iteration */
1877 /* see how much plain bits we can stuff into one packet
1878 * using RLE and VLI. */
1880 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
1881 : _drbd_bm_find_next(mdev, c->bit_offset);
1884 rl = tmp - c->bit_offset;
1886 if (toggle == 2) { /* first iteration */
1888 /* the first checked bit was set,
1889 * store start value, */
1890 DCBP_set_start(p, 1);
1891 /* but skip encoding of zero run length */
1895 DCBP_set_start(p, 0);
1898 /* paranoia: catch zero runlength.
1899 * can only happen if bitmap is modified while we scan it. */
1901 dev_err(DEV, "unexpected zero runlength while encoding bitmap "
1902 "t:%u bo:%lu\n", toggle, c->bit_offset);
1906 bits = vli_encode_bits(&bs, rl);
1907 if (bits == -ENOBUFS) /* buffer full */
1910 dev_err(DEV, "error while encoding bitmap: %d\n", bits);
1916 c->bit_offset = tmp;
1917 } while (c->bit_offset < c->bm_bits);
1919 len = bs.cur.b - p->code + !!bs.cur.bit;
1921 if (plain_bits < (len << 3)) {
1922 /* incompressible with this method.
1923 * we need to rewind both word and bit position. */
1924 c->bit_offset -= plain_bits;
1925 bm_xfer_ctx_bit_to_word_offset(c);
1926 c->bit_offset = c->word_offset * BITS_PER_LONG;
1930 /* RLE + VLI was able to compress it just fine.
1931 * update c->word_offset. */
1932 bm_xfer_ctx_bit_to_word_offset(c);
1934 /* store pad_bits */
1935 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
1940 enum { OK, FAILED, DONE }
1941 send_bitmap_rle_or_plain(struct drbd_conf *mdev,
1942 struct p_header *h, struct bm_xfer_ctx *c)
1944 struct p_compressed_bm *p = (void*)h;
1945 unsigned long num_words;
1949 len = fill_bitmap_rle_bits(mdev, p, c);
1955 DCBP_set_code(p, RLE_VLI_Bits);
1956 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h,
1957 sizeof(*p) + len, 0);
1960 c->bytes[0] += sizeof(*p) + len;
1962 if (c->bit_offset >= c->bm_bits)
1965 /* was not compressible.
1966 * send a buffer full of plain text bits instead. */
1967 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
1968 len = num_words * sizeof(long);
1970 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
1971 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP,
1972 h, sizeof(struct p_header) + len, 0);
1973 c->word_offset += num_words;
1974 c->bit_offset = c->word_offset * BITS_PER_LONG;
1977 c->bytes[1] += sizeof(struct p_header) + len;
1979 if (c->bit_offset > c->bm_bits)
1980 c->bit_offset = c->bm_bits;
1982 ok = ok ? ((len == 0) ? DONE : OK) : FAILED;
1985 INFO_bm_xfer_stats(mdev, "send", c);
1989 /* See the comment at receive_bitmap() */
1990 int _drbd_send_bitmap(struct drbd_conf *mdev)
1992 struct bm_xfer_ctx c;
1996 ERR_IF(!mdev->bitmap) return FALSE;
1998 /* maybe we should use some per thread scratch page,
1999 * and allocate that during initial device creation? */
2000 p = (struct p_header *) __get_free_page(GFP_NOIO);
2002 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
2006 if (get_ldev(mdev)) {
2007 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
2008 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
2009 drbd_bm_set_all(mdev);
2010 if (drbd_bm_write(mdev)) {
2011 /* write_bm did fail! Leave full sync flag set in Meta P_DATA
2012 * but otherwise process as per normal - need to tell other
2013 * side that a full resync is required! */
2014 dev_err(DEV, "Failed to write bitmap to disk!\n");
2016 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2023 c = (struct bm_xfer_ctx) {
2024 .bm_bits = drbd_bm_bits(mdev),
2025 .bm_words = drbd_bm_words(mdev),
2029 ret = send_bitmap_rle_or_plain(mdev, p, &c);
2030 } while (ret == OK);
2032 free_page((unsigned long) p);
2033 return (ret == DONE);
2036 int drbd_send_bitmap(struct drbd_conf *mdev)
2040 if (!drbd_get_data_sock(mdev))
2042 err = !_drbd_send_bitmap(mdev);
2043 drbd_put_data_sock(mdev);
2047 int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
2050 struct p_barrier_ack p;
2052 p.barrier = barrier_nr;
2053 p.set_size = cpu_to_be32(set_size);
2055 if (mdev->state.conn < C_CONNECTED)
2057 ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK,
2058 (struct p_header *)&p, sizeof(p));
2063 * _drbd_send_ack() - Sends an ack packet
2064 * @mdev: DRBD device.
2065 * @cmd: Packet command code.
2066 * @sector: sector, needs to be in big endian byte order
2067 * @blksize: size in byte, needs to be in big endian byte order
2068 * @block_id: Id, big endian byte order
2070 static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
2076 struct p_block_ack p;
2079 p.block_id = block_id;
2080 p.blksize = blksize;
2081 p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq));
2083 if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED)
2085 ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd,
2086 (struct p_header *)&p, sizeof(p));
2090 int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
2093 const int header_size = sizeof(struct p_data)
2094 - sizeof(struct p_header);
2095 int data_size = ((struct p_header *)dp)->length - header_size;
2097 return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
2101 int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
2102 struct p_block_req *rp)
2104 return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
2108 * drbd_send_ack() - Sends an ack packet
2109 * @mdev: DRBD device.
2110 * @cmd: Packet command code.
2113 int drbd_send_ack(struct drbd_conf *mdev,
2114 enum drbd_packets cmd, struct drbd_epoch_entry *e)
2116 return _drbd_send_ack(mdev, cmd,
2117 cpu_to_be64(e->sector),
2118 cpu_to_be32(e->size),
2122 /* This function misuses the block_id field to signal if the blocks
2123 * are is sync or not. */
2124 int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
2125 sector_t sector, int blksize, u64 block_id)
2127 return _drbd_send_ack(mdev, cmd,
2128 cpu_to_be64(sector),
2129 cpu_to_be32(blksize),
2130 cpu_to_be64(block_id));
2133 int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
2134 sector_t sector, int size, u64 block_id)
2137 struct p_block_req p;
2139 p.sector = cpu_to_be64(sector);
2140 p.block_id = block_id;
2141 p.blksize = cpu_to_be32(size);
2143 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd,
2144 (struct p_header *)&p, sizeof(p));
2148 int drbd_send_drequest_csum(struct drbd_conf *mdev,
2149 sector_t sector, int size,
2150 void *digest, int digest_size,
2151 enum drbd_packets cmd)
2154 struct p_block_req p;
2156 p.sector = cpu_to_be64(sector);
2157 p.block_id = BE_DRBD_MAGIC + 0xbeef;
2158 p.blksize = cpu_to_be32(size);
2160 p.head.magic = BE_DRBD_MAGIC;
2161 p.head.command = cpu_to_be16(cmd);
2162 p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header) + digest_size);
2164 mutex_lock(&mdev->data.mutex);
2166 ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0));
2167 ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0));
2169 mutex_unlock(&mdev->data.mutex);
2174 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
2177 struct p_block_req p;
2179 p.sector = cpu_to_be64(sector);
2180 p.block_id = BE_DRBD_MAGIC + 0xbabe;
2181 p.blksize = cpu_to_be32(size);
2183 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST,
2184 (struct p_header *)&p, sizeof(p));
2188 /* called on sndtimeo
2189 * returns FALSE if we should retry,
2190 * TRUE if we think connection is dead
2192 static int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock)
2195 /* long elapsed = (long)(jiffies - mdev->last_received); */
2197 drop_it = mdev->meta.socket == sock
2198 || !mdev->asender.task
2199 || get_t_state(&mdev->asender) != Running
2200 || mdev->state.conn < C_CONNECTED;
2205 drop_it = !--mdev->ko_count;
2207 dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
2208 current->comm, current->pid, mdev->ko_count);
2212 return drop_it; /* && (mdev->state == R_PRIMARY) */;
2215 /* The idea of sendpage seems to be to put some kind of reference
2216 * to the page into the skb, and to hand it over to the NIC. In
2217 * this process get_page() gets called.
2219 * As soon as the page was really sent over the network put_page()
2220 * gets called by some part of the network layer. [ NIC driver? ]
2222 * [ get_page() / put_page() increment/decrement the count. If count
2223 * reaches 0 the page will be freed. ]
2225 * This works nicely with pages from FSs.
2226 * But this means that in protocol A we might signal IO completion too early!
2228 * In order not to corrupt data during a resync we must make sure
2229 * that we do not reuse our own buffer pages (EEs) to early, therefore
2230 * we have the net_ee list.
2232 * XFS seems to have problems, still, it submits pages with page_count == 0!
2233 * As a workaround, we disable sendpage on pages
2234 * with page_count == 0 or PageSlab.
2236 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
2237 int offset, size_t size)
2239 int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, 0);
2242 mdev->send_cnt += size>>9;
2243 return sent == size;
2246 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
2247 int offset, size_t size)
2249 mm_segment_t oldfs = get_fs();
2253 /* e.g. XFS meta- & log-data is in slab pages, which have a
2254 * page_count of 0 and/or have PageSlab() set.
2255 * we cannot use send_page for those, as that does get_page();
2256 * put_page(); and would cause either a VM_BUG directly, or
2257 * __page_cache_release a page that would actually still be referenced
2258 * by someone, leading to some obscure delayed Oops somewhere else. */
2259 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
2260 return _drbd_no_send_page(mdev, page, offset, size);
2262 drbd_update_congested(mdev);
2265 sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page,
2268 if (sent == -EAGAIN) {
2269 if (we_should_drop_the_connection(mdev,
2276 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
2277 __func__, (int)size, len, sent);
2282 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
2284 clear_bit(NET_CONGESTED, &mdev->flags);
2288 mdev->send_cnt += size>>9;
2292 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
2294 struct bio_vec *bvec;
2296 __bio_for_each_segment(bvec, bio, i, 0) {
2297 if (!_drbd_no_send_page(mdev, bvec->bv_page,
2298 bvec->bv_offset, bvec->bv_len))
2304 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
2306 struct bio_vec *bvec;
2308 __bio_for_each_segment(bvec, bio, i, 0) {
2309 if (!_drbd_send_page(mdev, bvec->bv_page,
2310 bvec->bv_offset, bvec->bv_len))
2317 /* Used to send write requests
2318 * R_PRIMARY -> Peer (P_DATA)
2320 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
2324 unsigned int dp_flags = 0;
2328 if (!drbd_get_data_sock(mdev))
2331 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2332 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2334 p.head.magic = BE_DRBD_MAGIC;
2335 p.head.command = cpu_to_be16(P_DATA);
2337 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + req->size);
2339 p.sector = cpu_to_be64(req->sector);
2340 p.block_id = (unsigned long)req;
2341 p.seq_num = cpu_to_be32(req->seq_num =
2342 atomic_add_return(1, &mdev->packet_seq));
2345 /* NOTE: no need to check if barriers supported here as we would
2346 * not pass the test in make_request_common in that case
2348 if (bio_rw_flagged(req->master_bio, BIO_RW_BARRIER)) {
2349 dev_err(DEV, "ASSERT FAILED would have set DP_HARDBARRIER\n");
2350 /* dp_flags |= DP_HARDBARRIER; */
2352 if (bio_rw_flagged(req->master_bio, BIO_RW_SYNCIO))
2353 dp_flags |= DP_RW_SYNC;
2354 /* for now handle SYNCIO and UNPLUG
2355 * as if they still were one and the same flag */
2356 if (bio_rw_flagged(req->master_bio, BIO_RW_UNPLUG))
2357 dp_flags |= DP_RW_SYNC;
2358 if (mdev->state.conn >= C_SYNC_SOURCE &&
2359 mdev->state.conn <= C_PAUSED_SYNC_T)
2360 dp_flags |= DP_MAY_SET_IN_SYNC;
2362 p.dp_flags = cpu_to_be32(dp_flags);
2363 trace_drbd_packet(mdev, mdev->data.socket, 0, (void *)&p, __FILE__, __LINE__);
2364 set_bit(UNPLUG_REMOTE, &mdev->flags);
2366 drbd_send(mdev, mdev->data.socket, &p, sizeof(p), MSG_MORE));
2368 dgb = mdev->int_dig_out;
2369 drbd_csum(mdev, mdev->integrity_w_tfm, req->master_bio, dgb);
2370 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2373 if (mdev->net_conf->wire_protocol == DRBD_PROT_A)
2374 ok = _drbd_send_bio(mdev, req->master_bio);
2376 ok = _drbd_send_zc_bio(mdev, req->master_bio);
2379 drbd_put_data_sock(mdev);
2383 /* answer packet, used to send data back for read requests:
2384 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
2385 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
2387 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
2388 struct drbd_epoch_entry *e)
2395 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
2396 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
2398 p.head.magic = BE_DRBD_MAGIC;
2399 p.head.command = cpu_to_be16(cmd);
2401 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + e->size);
2403 p.sector = cpu_to_be64(e->sector);
2404 p.block_id = e->block_id;
2405 /* p.seq_num = 0; No sequence numbers here.. */
2407 /* Only called by our kernel thread.
2408 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
2409 * in response to admin command or module unload.
2411 if (!drbd_get_data_sock(mdev))
2414 trace_drbd_packet(mdev, mdev->data.socket, 0, (void *)&p, __FILE__, __LINE__);
2415 ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p,
2416 sizeof(p), MSG_MORE);
2418 dgb = mdev->int_dig_out;
2419 drbd_csum(mdev, mdev->integrity_w_tfm, e->private_bio, dgb);
2420 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
2423 ok = _drbd_send_zc_bio(mdev, e->private_bio);
2425 drbd_put_data_sock(mdev);
2430 drbd_send distinguishes two cases:
2432 Packets sent via the data socket "sock"
2433 and packets sent via the meta data socket "msock"
2436 -----------------+-------------------------+------------------------------
2437 timeout conf.timeout / 2 conf.timeout / 2
2438 timeout action send a ping via msock Abort communication
2439 and close all sockets
2443 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
2445 int drbd_send(struct drbd_conf *mdev, struct socket *sock,
2446 void *buf, size_t size, unsigned msg_flags)
2455 /* THINK if (signal_pending) return ... ? */
2460 msg.msg_name = NULL;
2461 msg.msg_namelen = 0;
2462 msg.msg_control = NULL;
2463 msg.msg_controllen = 0;
2464 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
2466 if (sock == mdev->data.socket) {
2467 mdev->ko_count = mdev->net_conf->ko_count;
2468 drbd_update_congested(mdev);
2472 * tcp_sendmsg does _not_ use its size parameter at all ?
2474 * -EAGAIN on timeout, -EINTR on signal.
2477 * do we need to block DRBD_SIG if sock == &meta.socket ??
2478 * otherwise wake_asender() might interrupt some send_*Ack !
2480 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
2481 if (rv == -EAGAIN) {
2482 if (we_should_drop_the_connection(mdev, sock))
2489 flush_signals(current);
2497 } while (sent < size);
2499 if (sock == mdev->data.socket)
2500 clear_bit(NET_CONGESTED, &mdev->flags);
2503 if (rv != -EAGAIN) {
2504 dev_err(DEV, "%s_sendmsg returned %d\n",
2505 sock == mdev->meta.socket ? "msock" : "sock",
2507 drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE));
2509 drbd_force_state(mdev, NS(conn, C_TIMEOUT));
2515 static int drbd_open(struct block_device *bdev, fmode_t mode)
2517 struct drbd_conf *mdev = bdev->bd_disk->private_data;
2518 unsigned long flags;
2521 spin_lock_irqsave(&mdev->req_lock, flags);
2522 /* to have a stable mdev->state.role
2523 * and no race with updating open_cnt */
2525 if (mdev->state.role != R_PRIMARY) {
2526 if (mode & FMODE_WRITE)
2528 else if (!allow_oos)
2534 spin_unlock_irqrestore(&mdev->req_lock, flags);
2539 static int drbd_release(struct gendisk *gd, fmode_t mode)
2541 struct drbd_conf *mdev = gd->private_data;
2546 static void drbd_unplug_fn(struct request_queue *q)
2548 struct drbd_conf *mdev = q->queuedata;
2550 trace_drbd_unplug(mdev, "got unplugged");
2553 spin_lock_irq(q->queue_lock);
2555 spin_unlock_irq(q->queue_lock);
2557 /* only if connected */
2558 spin_lock_irq(&mdev->req_lock);
2559 if (mdev->state.pdsk >= D_INCONSISTENT && mdev->state.conn >= C_CONNECTED) {
2560 D_ASSERT(mdev->state.role == R_PRIMARY);
2561 if (test_and_clear_bit(UNPLUG_REMOTE, &mdev->flags)) {
2562 /* add to the data.work queue,
2563 * unless already queued.
2564 * XXX this might be a good addition to drbd_queue_work
2565 * anyways, to detect "double queuing" ... */
2566 if (list_empty(&mdev->unplug_work.list))
2567 drbd_queue_work(&mdev->data.work,
2568 &mdev->unplug_work);
2571 spin_unlock_irq(&mdev->req_lock);
2573 if (mdev->state.disk >= D_INCONSISTENT)
2577 static void drbd_set_defaults(struct drbd_conf *mdev)
2579 mdev->sync_conf.after = DRBD_AFTER_DEF;
2580 mdev->sync_conf.rate = DRBD_RATE_DEF;
2581 mdev->sync_conf.al_extents = DRBD_AL_EXTENTS_DEF;
2582 mdev->state = (union drbd_state) {
2583 { .role = R_SECONDARY,
2585 .conn = C_STANDALONE,
2592 void drbd_init_set_defaults(struct drbd_conf *mdev)
2594 /* the memset(,0,) did most of this.
2595 * note: only assignments, no allocation in here */
2597 drbd_set_defaults(mdev);
2599 /* for now, we do NOT yet support it,
2600 * even though we start some framework
2601 * to eventually support barriers */
2602 set_bit(NO_BARRIER_SUPP, &mdev->flags);
2604 atomic_set(&mdev->ap_bio_cnt, 0);
2605 atomic_set(&mdev->ap_pending_cnt, 0);
2606 atomic_set(&mdev->rs_pending_cnt, 0);
2607 atomic_set(&mdev->unacked_cnt, 0);
2608 atomic_set(&mdev->local_cnt, 0);
2609 atomic_set(&mdev->net_cnt, 0);
2610 atomic_set(&mdev->packet_seq, 0);
2611 atomic_set(&mdev->pp_in_use, 0);
2613 mutex_init(&mdev->md_io_mutex);
2614 mutex_init(&mdev->data.mutex);
2615 mutex_init(&mdev->meta.mutex);
2616 sema_init(&mdev->data.work.s, 0);
2617 sema_init(&mdev->meta.work.s, 0);
2618 mutex_init(&mdev->state_mutex);
2620 spin_lock_init(&mdev->data.work.q_lock);
2621 spin_lock_init(&mdev->meta.work.q_lock);
2623 spin_lock_init(&mdev->al_lock);
2624 spin_lock_init(&mdev->req_lock);
2625 spin_lock_init(&mdev->peer_seq_lock);
2626 spin_lock_init(&mdev->epoch_lock);
2628 INIT_LIST_HEAD(&mdev->active_ee);
2629 INIT_LIST_HEAD(&mdev->sync_ee);
2630 INIT_LIST_HEAD(&mdev->done_ee);
2631 INIT_LIST_HEAD(&mdev->read_ee);
2632 INIT_LIST_HEAD(&mdev->net_ee);
2633 INIT_LIST_HEAD(&mdev->resync_reads);
2634 INIT_LIST_HEAD(&mdev->data.work.q);
2635 INIT_LIST_HEAD(&mdev->meta.work.q);
2636 INIT_LIST_HEAD(&mdev->resync_work.list);
2637 INIT_LIST_HEAD(&mdev->unplug_work.list);
2638 INIT_LIST_HEAD(&mdev->md_sync_work.list);
2639 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
2640 mdev->resync_work.cb = w_resync_inactive;
2641 mdev->unplug_work.cb = w_send_write_hint;
2642 mdev->md_sync_work.cb = w_md_sync;
2643 mdev->bm_io_work.w.cb = w_bitmap_io;
2644 init_timer(&mdev->resync_timer);
2645 init_timer(&mdev->md_sync_timer);
2646 mdev->resync_timer.function = resync_timer_fn;
2647 mdev->resync_timer.data = (unsigned long) mdev;
2648 mdev->md_sync_timer.function = md_sync_timer_fn;
2649 mdev->md_sync_timer.data = (unsigned long) mdev;
2651 init_waitqueue_head(&mdev->misc_wait);
2652 init_waitqueue_head(&mdev->state_wait);
2653 init_waitqueue_head(&mdev->ee_wait);
2654 init_waitqueue_head(&mdev->al_wait);
2655 init_waitqueue_head(&mdev->seq_wait);
2657 drbd_thread_init(mdev, &mdev->receiver, drbdd_init);
2658 drbd_thread_init(mdev, &mdev->worker, drbd_worker);
2659 drbd_thread_init(mdev, &mdev->asender, drbd_asender);
2661 mdev->agreed_pro_version = PRO_VERSION_MAX;
2662 mdev->write_ordering = WO_bio_barrier;
2663 mdev->resync_wenr = LC_FREE;
2666 void drbd_mdev_cleanup(struct drbd_conf *mdev)
2668 if (mdev->receiver.t_state != None)
2669 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
2670 mdev->receiver.t_state);
2672 /* no need to lock it, I'm the only thread alive */
2673 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
2674 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
2685 mdev->rs_mark_left =
2686 mdev->rs_mark_time = 0;
2687 D_ASSERT(mdev->net_conf == NULL);
2689 drbd_set_my_capacity(mdev, 0);
2691 /* maybe never allocated. */
2692 drbd_bm_resize(mdev, 0);
2693 drbd_bm_cleanup(mdev);
2696 drbd_free_resources(mdev);
2699 * currently we drbd_init_ee only on module load, so
2700 * we may do drbd_release_ee only on module unload!
2702 D_ASSERT(list_empty(&mdev->active_ee));
2703 D_ASSERT(list_empty(&mdev->sync_ee));
2704 D_ASSERT(list_empty(&mdev->done_ee));
2705 D_ASSERT(list_empty(&mdev->read_ee));
2706 D_ASSERT(list_empty(&mdev->net_ee));
2707 D_ASSERT(list_empty(&mdev->resync_reads));
2708 D_ASSERT(list_empty(&mdev->data.work.q));
2709 D_ASSERT(list_empty(&mdev->meta.work.q));
2710 D_ASSERT(list_empty(&mdev->resync_work.list));
2711 D_ASSERT(list_empty(&mdev->unplug_work.list));
2716 static void drbd_destroy_mempools(void)
2720 while (drbd_pp_pool) {
2721 page = drbd_pp_pool;
2722 drbd_pp_pool = (struct page *)page_private(page);
2727 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
2729 if (drbd_ee_mempool)
2730 mempool_destroy(drbd_ee_mempool);
2731 if (drbd_request_mempool)
2732 mempool_destroy(drbd_request_mempool);
2734 kmem_cache_destroy(drbd_ee_cache);
2735 if (drbd_request_cache)
2736 kmem_cache_destroy(drbd_request_cache);
2737 if (drbd_bm_ext_cache)
2738 kmem_cache_destroy(drbd_bm_ext_cache);
2739 if (drbd_al_ext_cache)
2740 kmem_cache_destroy(drbd_al_ext_cache);
2742 drbd_ee_mempool = NULL;
2743 drbd_request_mempool = NULL;
2744 drbd_ee_cache = NULL;
2745 drbd_request_cache = NULL;
2746 drbd_bm_ext_cache = NULL;
2747 drbd_al_ext_cache = NULL;
2752 static int drbd_create_mempools(void)
2755 const int number = (DRBD_MAX_SEGMENT_SIZE/PAGE_SIZE) * minor_count;
2758 /* prepare our caches and mempools */
2759 drbd_request_mempool = NULL;
2760 drbd_ee_cache = NULL;
2761 drbd_request_cache = NULL;
2762 drbd_bm_ext_cache = NULL;
2763 drbd_al_ext_cache = NULL;
2764 drbd_pp_pool = NULL;
2767 drbd_request_cache = kmem_cache_create(
2768 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
2769 if (drbd_request_cache == NULL)
2772 drbd_ee_cache = kmem_cache_create(
2773 "drbd_ee", sizeof(struct drbd_epoch_entry), 0, 0, NULL);
2774 if (drbd_ee_cache == NULL)
2777 drbd_bm_ext_cache = kmem_cache_create(
2778 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
2779 if (drbd_bm_ext_cache == NULL)
2782 drbd_al_ext_cache = kmem_cache_create(
2783 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
2784 if (drbd_al_ext_cache == NULL)
2788 drbd_request_mempool = mempool_create(number,
2789 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
2790 if (drbd_request_mempool == NULL)
2793 drbd_ee_mempool = mempool_create(number,
2794 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2795 if (drbd_request_mempool == NULL)
2798 /* drbd's page pool */
2799 spin_lock_init(&drbd_pp_lock);
2801 for (i = 0; i < number; i++) {
2802 page = alloc_page(GFP_HIGHUSER);
2805 set_page_private(page, (unsigned long)drbd_pp_pool);
2806 drbd_pp_pool = page;
2808 drbd_pp_vacant = number;
2813 drbd_destroy_mempools(); /* in case we allocated some */
2817 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
2820 /* just so we have it. you never know what interesting things we
2821 * might want to do here some day...
2827 static struct notifier_block drbd_notifier = {
2828 .notifier_call = drbd_notify_sys,
2831 static void drbd_release_ee_lists(struct drbd_conf *mdev)
2835 rr = drbd_release_ee(mdev, &mdev->active_ee);
2837 dev_err(DEV, "%d EEs in active list found!\n", rr);
2839 rr = drbd_release_ee(mdev, &mdev->sync_ee);
2841 dev_err(DEV, "%d EEs in sync list found!\n", rr);
2843 rr = drbd_release_ee(mdev, &mdev->read_ee);
2845 dev_err(DEV, "%d EEs in read list found!\n", rr);
2847 rr = drbd_release_ee(mdev, &mdev->done_ee);
2849 dev_err(DEV, "%d EEs in done list found!\n", rr);
2851 rr = drbd_release_ee(mdev, &mdev->net_ee);
2853 dev_err(DEV, "%d EEs in net list found!\n", rr);
2856 /* caution. no locking.
2857 * currently only used from module cleanup code. */
2858 static void drbd_delete_device(unsigned int minor)
2860 struct drbd_conf *mdev = minor_to_mdev(minor);
2865 /* paranoia asserts */
2866 if (mdev->open_cnt != 0)
2867 dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,
2868 __FILE__ , __LINE__);
2870 ERR_IF (!list_empty(&mdev->data.work.q)) {
2871 struct list_head *lp;
2872 list_for_each(lp, &mdev->data.work.q) {
2873 dev_err(DEV, "lp = %p\n", lp);
2876 /* end paranoia asserts */
2878 del_gendisk(mdev->vdisk);
2880 /* cleanup stuff that may have been allocated during
2881 * device (re-)configuration or state changes */
2883 if (mdev->this_bdev)
2884 bdput(mdev->this_bdev);
2886 drbd_free_resources(mdev);
2888 drbd_release_ee_lists(mdev);
2890 /* should be free'd on disconnect? */
2891 kfree(mdev->ee_hash);
2893 mdev->ee_hash_s = 0;
2894 mdev->ee_hash = NULL;
2897 lc_destroy(mdev->act_log);
2898 lc_destroy(mdev->resync);
2900 kfree(mdev->p_uuid);
2901 /* mdev->p_uuid = NULL; */
2903 kfree(mdev->int_dig_out);
2904 kfree(mdev->int_dig_in);
2905 kfree(mdev->int_dig_vv);
2907 /* cleanup the rest that has been
2908 * allocated from drbd_new_device
2909 * and actually free the mdev itself */
2910 drbd_free_mdev(mdev);
2913 static void drbd_cleanup(void)
2917 unregister_reboot_notifier(&drbd_notifier);
2923 remove_proc_entry("drbd", NULL);
2926 drbd_delete_device(i);
2927 drbd_destroy_mempools();
2932 unregister_blkdev(DRBD_MAJOR, "drbd");
2934 printk(KERN_INFO "drbd: module cleanup done.\n");
2938 * drbd_congested() - Callback for pdflush
2939 * @congested_data: User data
2940 * @bdi_bits: Bits pdflush is currently interested in
2942 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
2944 static int drbd_congested(void *congested_data, int bdi_bits)
2946 struct drbd_conf *mdev = congested_data;
2947 struct request_queue *q;
2951 if (!__inc_ap_bio_cond(mdev)) {
2952 /* DRBD has frozen IO */
2958 if (get_ldev(mdev)) {
2959 q = bdev_get_queue(mdev->ldev->backing_bdev);
2960 r = bdi_congested(&q->backing_dev_info, bdi_bits);
2966 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) {
2967 r |= (1 << BDI_async_congested);
2968 reason = reason == 'b' ? 'a' : 'n';
2972 mdev->congestion_reason = reason;
2976 struct drbd_conf *drbd_new_device(unsigned int minor)
2978 struct drbd_conf *mdev;
2979 struct gendisk *disk;
2980 struct request_queue *q;
2982 /* GFP_KERNEL, we are outside of all write-out paths */
2983 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
2986 if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL))
2987 goto out_no_cpumask;
2989 mdev->minor = minor;
2991 drbd_init_set_defaults(mdev);
2993 q = blk_alloc_queue(GFP_KERNEL);
2997 q->queuedata = mdev;
2998 blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE);
3000 disk = alloc_disk(1);
3005 set_disk_ro(disk, TRUE);
3008 disk->major = DRBD_MAJOR;
3009 disk->first_minor = minor;
3010 disk->fops = &drbd_ops;
3011 sprintf(disk->disk_name, "drbd%d", minor);
3012 disk->private_data = mdev;
3014 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
3015 /* we have no partitions. we contain only ourselves. */
3016 mdev->this_bdev->bd_contains = mdev->this_bdev;
3018 q->backing_dev_info.congested_fn = drbd_congested;
3019 q->backing_dev_info.congested_data = mdev;
3021 blk_queue_make_request(q, drbd_make_request_26);
3022 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
3023 blk_queue_merge_bvec(q, drbd_merge_bvec);
3024 q->queue_lock = &mdev->req_lock; /* needed since we use */
3025 /* plugging on a queue, that actually has no requests! */
3026 q->unplug_fn = drbd_unplug_fn;
3028 mdev->md_io_page = alloc_page(GFP_KERNEL);
3029 if (!mdev->md_io_page)
3030 goto out_no_io_page;
3032 if (drbd_bm_init(mdev))
3034 /* no need to lock access, we are still initializing this minor device. */
3038 mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL);
3039 if (!mdev->app_reads_hash)
3040 goto out_no_app_reads;
3042 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
3043 if (!mdev->current_epoch)
3046 INIT_LIST_HEAD(&mdev->current_epoch->list);
3051 /* out_whatever_else:
3052 kfree(mdev->current_epoch); */
3054 kfree(mdev->app_reads_hash);
3058 drbd_bm_cleanup(mdev);
3060 __free_page(mdev->md_io_page);
3064 blk_cleanup_queue(q);
3066 free_cpumask_var(mdev->cpu_mask);
3072 /* counterpart of drbd_new_device.
3073 * last part of drbd_delete_device. */
3074 void drbd_free_mdev(struct drbd_conf *mdev)
3076 kfree(mdev->current_epoch);
3077 kfree(mdev->app_reads_hash);
3079 if (mdev->bitmap) /* should no longer be there. */
3080 drbd_bm_cleanup(mdev);
3081 __free_page(mdev->md_io_page);
3082 put_disk(mdev->vdisk);
3083 blk_cleanup_queue(mdev->rq_queue);
3084 free_cpumask_var(mdev->cpu_mask);
3089 int __init drbd_init(void)
3093 if (sizeof(struct p_handshake) != 80) {
3095 "drbd: never change the size or layout "
3096 "of the HandShake packet.\n");
3100 if (1 > minor_count || minor_count > 255) {
3102 "drbd: invalid minor_count (%d)\n", minor_count);
3110 err = drbd_nl_init();
3114 err = register_blkdev(DRBD_MAJOR, "drbd");
3117 "drbd: unable to register block device major %d\n",
3122 register_reboot_notifier(&drbd_notifier);
3125 * allocate all necessary structs
3129 init_waitqueue_head(&drbd_pp_wait);
3131 drbd_proc = NULL; /* play safe for drbd_cleanup */
3132 minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
3137 err = drbd_create_mempools();
3141 drbd_proc = proc_create("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops);
3143 printk(KERN_ERR "drbd: unable to register proc file\n");
3147 rwlock_init(&global_state_lock);
3149 printk(KERN_INFO "drbd: initialized. "
3150 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
3151 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
3152 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
3153 printk(KERN_INFO "drbd: registered as block device major %d\n",
3155 printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
3157 return 0; /* Success! */
3162 /* currently always the case */
3163 printk(KERN_ERR "drbd: ran out of memory\n");
3165 printk(KERN_ERR "drbd: initialization failure\n");
3169 void drbd_free_bc(struct drbd_backing_dev *ldev)
3174 bd_release(ldev->backing_bdev);
3175 bd_release(ldev->md_bdev);
3177 fput(ldev->lo_file);
3178 fput(ldev->md_file);
3183 void drbd_free_sock(struct drbd_conf *mdev)
3185 if (mdev->data.socket) {
3186 kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR);
3187 sock_release(mdev->data.socket);
3188 mdev->data.socket = NULL;
3190 if (mdev->meta.socket) {
3191 kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR);
3192 sock_release(mdev->meta.socket);
3193 mdev->meta.socket = NULL;
3198 void drbd_free_resources(struct drbd_conf *mdev)
3200 crypto_free_hash(mdev->csums_tfm);
3201 mdev->csums_tfm = NULL;
3202 crypto_free_hash(mdev->verify_tfm);
3203 mdev->verify_tfm = NULL;
3204 crypto_free_hash(mdev->cram_hmac_tfm);
3205 mdev->cram_hmac_tfm = NULL;
3206 crypto_free_hash(mdev->integrity_w_tfm);
3207 mdev->integrity_w_tfm = NULL;
3208 crypto_free_hash(mdev->integrity_r_tfm);
3209 mdev->integrity_r_tfm = NULL;
3211 drbd_free_sock(mdev);
3214 drbd_free_bc(mdev->ldev);
3215 mdev->ldev = NULL;);
3218 /* meta data management */
3220 struct meta_data_on_disk {
3221 u64 la_size; /* last agreed size. */
3222 u64 uuid[UI_SIZE]; /* UUIDs. */
3225 u32 flags; /* MDF */
3228 u32 al_offset; /* offset to this block */
3229 u32 al_nr_extents; /* important for restoring the AL */
3230 /* `-- act_log->nr_elements <-- sync_conf.al_extents */
3231 u32 bm_offset; /* offset to the bitmap, from here */
3232 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
3233 u32 reserved_u32[4];
3238 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
3239 * @mdev: DRBD device.
3241 void drbd_md_sync(struct drbd_conf *mdev)
3243 struct meta_data_on_disk *buffer;
3247 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
3249 del_timer(&mdev->md_sync_timer);
3251 /* We use here D_FAILED and not D_ATTACHING because we try to write
3252 * metadata even if we detach due to a disk failure! */
3253 if (!get_ldev_if_state(mdev, D_FAILED))
3256 trace_drbd_md_io(mdev, WRITE, mdev->ldev);
3258 mutex_lock(&mdev->md_io_mutex);
3259 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3260 memset(buffer, 0, 512);
3262 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
3263 for (i = UI_CURRENT; i < UI_SIZE; i++)
3264 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
3265 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
3266 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
3268 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
3269 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
3270 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
3271 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
3272 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
3274 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
3276 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
3277 sector = mdev->ldev->md.md_offset;
3279 if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
3280 clear_bit(MD_DIRTY, &mdev->flags);
3282 /* this was a try anyways ... */
3283 dev_err(DEV, "meta data update failed!\n");
3285 drbd_chk_io_error(mdev, 1, TRUE);
3288 /* Update mdev->ldev->md.la_size_sect,
3289 * since we updated it on metadata. */
3290 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
3292 mutex_unlock(&mdev->md_io_mutex);
3297 * drbd_md_read() - Reads in the meta data super block
3298 * @mdev: DRBD device.
3299 * @bdev: Device from which the meta data should be read in.
3301 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_codes in case
3302 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
3304 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
3306 struct meta_data_on_disk *buffer;
3307 int i, rv = NO_ERROR;
3309 if (!get_ldev_if_state(mdev, D_ATTACHING))
3310 return ERR_IO_MD_DISK;
3312 trace_drbd_md_io(mdev, READ, bdev);
3314 mutex_lock(&mdev->md_io_mutex);
3315 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
3317 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
3318 /* NOTE: cant do normal error processing here as this is
3319 called BEFORE disk is attached */
3320 dev_err(DEV, "Error while reading metadata.\n");
3321 rv = ERR_IO_MD_DISK;
3325 if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) {
3326 dev_err(DEV, "Error while reading metadata, magic not found.\n");
3327 rv = ERR_MD_INVALID;
3330 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
3331 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
3332 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
3333 rv = ERR_MD_INVALID;
3336 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
3337 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
3338 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
3339 rv = ERR_MD_INVALID;
3342 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
3343 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
3344 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
3345 rv = ERR_MD_INVALID;
3349 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
3350 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
3351 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
3352 rv = ERR_MD_INVALID;
3356 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
3357 for (i = UI_CURRENT; i < UI_SIZE; i++)
3358 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
3359 bdev->md.flags = be32_to_cpu(buffer->flags);
3360 mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents);
3361 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
3363 if (mdev->sync_conf.al_extents < 7)
3364 mdev->sync_conf.al_extents = 127;
3367 mutex_unlock(&mdev->md_io_mutex);
3374 * drbd_md_mark_dirty() - Mark meta data super block as dirty
3375 * @mdev: DRBD device.
3377 * Call this function if you change anything that should be written to
3378 * the meta-data super block. This function sets MD_DIRTY, and starts a
3379 * timer that ensures that within five seconds you have to call drbd_md_sync().
3381 void drbd_md_mark_dirty(struct drbd_conf *mdev)
3383 set_bit(MD_DIRTY, &mdev->flags);
3384 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
3388 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
3392 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++) {
3393 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
3395 trace_drbd_uuid(mdev, i+1);
3399 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3401 if (idx == UI_CURRENT) {
3402 if (mdev->state.role == R_PRIMARY)
3407 drbd_set_ed_uuid(mdev, val);
3410 mdev->ldev->md.uuid[idx] = val;
3411 trace_drbd_uuid(mdev, idx);
3412 drbd_md_mark_dirty(mdev);
3416 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
3418 if (mdev->ldev->md.uuid[idx]) {
3419 drbd_uuid_move_history(mdev);
3420 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
3421 trace_drbd_uuid(mdev, UI_HISTORY_START);
3423 _drbd_uuid_set(mdev, idx, val);
3427 * drbd_uuid_new_current() - Creates a new current UUID
3428 * @mdev: DRBD device.
3430 * Creates a new current UUID, and rotates the old current UUID into
3431 * the bitmap slot. Causes an incremental resync upon next connect.
3433 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
3437 dev_info(DEV, "Creating new current UUID\n");
3438 D_ASSERT(mdev->ldev->md.uuid[UI_BITMAP] == 0);
3439 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
3440 trace_drbd_uuid(mdev, UI_BITMAP);
3442 get_random_bytes(&val, sizeof(u64));
3443 _drbd_uuid_set(mdev, UI_CURRENT, val);
3446 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
3448 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
3452 drbd_uuid_move_history(mdev);
3453 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
3454 mdev->ldev->md.uuid[UI_BITMAP] = 0;
3455 trace_drbd_uuid(mdev, UI_HISTORY_START);
3456 trace_drbd_uuid(mdev, UI_BITMAP);
3458 if (mdev->ldev->md.uuid[UI_BITMAP])
3459 dev_warn(DEV, "bm UUID already set");
3461 mdev->ldev->md.uuid[UI_BITMAP] = val;
3462 mdev->ldev->md.uuid[UI_BITMAP] &= ~((u64)1);
3464 trace_drbd_uuid(mdev, UI_BITMAP);
3466 drbd_md_mark_dirty(mdev);
3470 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3471 * @mdev: DRBD device.
3473 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
3475 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
3479 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3480 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
3482 drbd_bm_set_all(mdev);
3484 rv = drbd_bm_write(mdev);
3487 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
3498 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
3499 * @mdev: DRBD device.
3501 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
3503 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
3507 if (get_ldev_if_state(mdev, D_ATTACHING)) {
3508 drbd_bm_clear_all(mdev);
3509 rv = drbd_bm_write(mdev);
3516 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3518 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
3521 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
3523 drbd_bm_lock(mdev, work->why);
3524 rv = work->io_fn(mdev);
3525 drbd_bm_unlock(mdev);
3527 clear_bit(BITMAP_IO, &mdev->flags);
3528 wake_up(&mdev->misc_wait);
3531 work->done(mdev, rv);
3533 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
3540 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
3541 * @mdev: DRBD device.
3542 * @io_fn: IO callback to be called when bitmap IO is possible
3543 * @done: callback to be called after the bitmap IO was performed
3544 * @why: Descriptive text of the reason for doing the IO
3546 * While IO on the bitmap happens we freeze application IO thus we ensure
3547 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
3548 * called from worker context. It MUST NOT be used while a previous such
3549 * work is still pending!
3551 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
3552 int (*io_fn)(struct drbd_conf *),
3553 void (*done)(struct drbd_conf *, int),
3556 D_ASSERT(current == mdev->worker.task);
3558 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
3559 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
3560 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
3561 if (mdev->bm_io_work.why)
3562 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
3563 why, mdev->bm_io_work.why);
3565 mdev->bm_io_work.io_fn = io_fn;
3566 mdev->bm_io_work.done = done;
3567 mdev->bm_io_work.why = why;
3569 set_bit(BITMAP_IO, &mdev->flags);
3570 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
3571 if (list_empty(&mdev->bm_io_work.w.list)) {
3572 set_bit(BITMAP_IO_QUEUED, &mdev->flags);
3573 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
3575 dev_err(DEV, "FIXME avoided double queuing bm_io_work\n");
3580 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
3581 * @mdev: DRBD device.
3582 * @io_fn: IO callback to be called when bitmap IO is possible
3583 * @why: Descriptive text of the reason for doing the IO
3585 * freezes application IO while that the actual IO operations runs. This
3586 * functions MAY NOT be called from worker context.
3588 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why)
3592 D_ASSERT(current != mdev->worker.task);
3594 drbd_suspend_io(mdev);
3596 drbd_bm_lock(mdev, why);
3598 drbd_bm_unlock(mdev);
3600 drbd_resume_io(mdev);
3605 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3607 if ((mdev->ldev->md.flags & flag) != flag) {
3608 drbd_md_mark_dirty(mdev);
3609 mdev->ldev->md.flags |= flag;
3613 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3615 if ((mdev->ldev->md.flags & flag) != 0) {
3616 drbd_md_mark_dirty(mdev);
3617 mdev->ldev->md.flags &= ~flag;
3620 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
3622 return (bdev->md.flags & flag) != 0;
3625 static void md_sync_timer_fn(unsigned long data)
3627 struct drbd_conf *mdev = (struct drbd_conf *) data;
3629 drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work);
3632 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused)
3634 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3640 #ifdef CONFIG_DRBD_FAULT_INJECTION
3641 /* Fault insertion support including random number generator shamelessly
3642 * stolen from kernel/rcutorture.c */
3643 struct fault_random_state {
3644 unsigned long state;
3645 unsigned long count;
3648 #define FAULT_RANDOM_MULT 39916801 /* prime */
3649 #define FAULT_RANDOM_ADD 479001701 /* prime */
3650 #define FAULT_RANDOM_REFRESH 10000
3653 * Crude but fast random-number generator. Uses a linear congruential
3654 * generator, with occasional help from get_random_bytes().
3656 static unsigned long
3657 _drbd_fault_random(struct fault_random_state *rsp)
3661 if (--rsp->count < 0) {
3662 get_random_bytes(&refresh, sizeof(refresh));
3663 rsp->state += refresh;
3664 rsp->count = FAULT_RANDOM_REFRESH;
3666 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
3667 return swahw32(rsp->state);
3671 _drbd_fault_str(unsigned int type) {
3672 static char *_faults[] = {
3673 [DRBD_FAULT_MD_WR] = "Meta-data write",
3674 [DRBD_FAULT_MD_RD] = "Meta-data read",
3675 [DRBD_FAULT_RS_WR] = "Resync write",
3676 [DRBD_FAULT_RS_RD] = "Resync read",
3677 [DRBD_FAULT_DT_WR] = "Data write",
3678 [DRBD_FAULT_DT_RD] = "Data read",
3679 [DRBD_FAULT_DT_RA] = "Data read ahead",
3680 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
3681 [DRBD_FAULT_AL_EE] = "EE allocation"
3684 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
3688 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
3690 static struct fault_random_state rrs = {0, 0};
3692 unsigned int ret = (
3694 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
3695 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
3700 if (printk_ratelimit())
3701 dev_warn(DEV, "***Simulating %s failure\n",
3702 _drbd_fault_str(type));
3709 const char *drbd_buildtag(void)
3711 /* DRBD built from external sources has here a reference to the
3712 git hash of the source code. */
3714 static char buildtag[38] = "\0uilt-in";
3716 if (buildtag[0] == 0) {
3717 #ifdef CONFIG_MODULES
3718 if (THIS_MODULE != NULL)
3719 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
3728 module_init(drbd_init)
3729 module_exit(drbd_cleanup)
3731 /* For drbd_tracing: */
3732 EXPORT_SYMBOL(drbd_conn_str);
3733 EXPORT_SYMBOL(drbd_role_str);
3734 EXPORT_SYMBOL(drbd_disk_str);
3735 EXPORT_SYMBOL(drbd_set_st_err_str);