4 This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
6 Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
7 Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>.
8 Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.
10 Thanks to Carter Burden, Bart Grantham and Gennadiy Nerubayev
11 from Logicworks, Inc. for making SDP replication support possible.
13 drbd is free software; you can redistribute it and/or modify
14 it under the terms of the GNU General Public License as published by
15 the Free Software Foundation; either version 2, or (at your option)
18 drbd is distributed in the hope that it will be useful,
19 but WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 GNU General Public License for more details.
23 You should have received a copy of the GNU General Public License
24 along with drbd; see the file COPYING. If not, write to
25 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
29 #include <linux/module.h>
30 #include <linux/drbd.h>
31 #include <asm/uaccess.h>
32 #include <asm/types.h>
34 #include <linux/ctype.h>
35 #include <linux/mutex.h>
37 #include <linux/file.h>
38 #include <linux/proc_fs.h>
39 #include <linux/init.h>
41 #include <linux/memcontrol.h>
42 #include <linux/mm_inline.h>
43 #include <linux/slab.h>
44 #include <linux/random.h>
45 #include <linux/reboot.h>
46 #include <linux/notifier.h>
47 #include <linux/kthread.h>
49 #define __KERNEL_SYSCALLS__
50 #include <linux/unistd.h>
51 #include <linux/vmalloc.h>
53 #include <linux/drbd_limits.h>
55 #include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */
59 static DEFINE_MUTEX(drbd_main_mutex);
60 int drbdd_init(struct drbd_thread *);
61 int drbd_worker(struct drbd_thread *);
62 int drbd_asender(struct drbd_thread *);
65 static int drbd_open(struct block_device *bdev, fmode_t mode);
66 static int drbd_release(struct gendisk *gd, fmode_t mode);
67 static int w_md_sync(struct drbd_work *w, int unused);
68 static void md_sync_timer_fn(unsigned long data);
69 static int w_bitmap_io(struct drbd_work *w, int unused);
70 static int w_go_diskless(struct drbd_work *w, int unused);
72 MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, "
73 "Lars Ellenberg <lars@linbit.com>");
74 MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION);
75 MODULE_VERSION(REL_VERSION);
76 MODULE_LICENSE("GPL");
77 MODULE_PARM_DESC(minor_count, "Approximate number of drbd devices ("
78 __stringify(DRBD_MINOR_COUNT_MIN) "-" __stringify(DRBD_MINOR_COUNT_MAX) ")");
79 MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR);
81 #include <linux/moduleparam.h>
82 /* allow_open_on_secondary */
83 MODULE_PARM_DESC(allow_oos, "DONT USE!");
84 /* thanks to these macros, if compiled into the kernel (not-module),
85 * this becomes the boot parameter drbd.minor_count */
86 module_param(minor_count, uint, 0444);
87 module_param(disable_sendpage, bool, 0644);
88 module_param(allow_oos, bool, 0);
89 module_param(proc_details, int, 0644);
91 #ifdef CONFIG_DRBD_FAULT_INJECTION
94 static int fault_count;
96 /* bitmap of enabled faults */
97 module_param(enable_faults, int, 0664);
98 /* fault rate % value - applies to all enabled faults */
99 module_param(fault_rate, int, 0664);
100 /* count of faults inserted */
101 module_param(fault_count, int, 0664);
102 /* bitmap of devices to insert faults on */
103 module_param(fault_devs, int, 0644);
106 /* module parameter, defined */
107 unsigned int minor_count = DRBD_MINOR_COUNT_DEF;
108 int disable_sendpage;
110 int proc_details; /* Detail level in proc drbd*/
112 /* Module parameter for setting the user mode helper program
113 * to run. Default is /sbin/drbdadm */
114 char usermode_helper[80] = "/sbin/drbdadm";
116 module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644);
118 /* in 2.6.x, our device mapping and config info contains our virtual gendisks
119 * as member "struct gendisk *vdisk;"
122 struct list_head drbd_tconns; /* list of struct drbd_tconn */
123 DEFINE_MUTEX(drbd_cfg_mutex);
125 struct kmem_cache *drbd_request_cache;
126 struct kmem_cache *drbd_ee_cache; /* peer requests */
127 struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */
128 struct kmem_cache *drbd_al_ext_cache; /* activity log extents */
129 mempool_t *drbd_request_mempool;
130 mempool_t *drbd_ee_mempool;
131 mempool_t *drbd_md_io_page_pool;
132 struct bio_set *drbd_md_io_bio_set;
134 /* I do not use a standard mempool, because:
135 1) I want to hand out the pre-allocated objects first.
136 2) I want to be able to interrupt sleeping allocation with a signal.
137 Note: This is a single linked list, the next pointer is the private
138 member of struct page.
140 struct page *drbd_pp_pool;
141 spinlock_t drbd_pp_lock;
143 wait_queue_head_t drbd_pp_wait;
145 DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5);
147 static const struct block_device_operations drbd_ops = {
148 .owner = THIS_MODULE,
150 .release = drbd_release,
153 static void bio_destructor_drbd(struct bio *bio)
155 bio_free(bio, drbd_md_io_bio_set);
158 struct bio *bio_alloc_drbd(gfp_t gfp_mask)
162 if (!drbd_md_io_bio_set)
163 return bio_alloc(gfp_mask, 1);
165 bio = bio_alloc_bioset(gfp_mask, 1, drbd_md_io_bio_set);
168 bio->bi_destructor = bio_destructor_drbd;
173 /* When checking with sparse, and this is an inline function, sparse will
174 give tons of false positives. When this is a real functions sparse works.
176 int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
180 atomic_inc(&mdev->local_cnt);
181 io_allowed = (mdev->state.disk >= mins);
183 if (atomic_dec_and_test(&mdev->local_cnt))
184 wake_up(&mdev->misc_wait);
192 * DOC: The transfer log
194 * The transfer log is a single linked list of &struct drbd_tl_epoch objects.
195 * mdev->tconn->newest_tle points to the head, mdev->tconn->oldest_tle points to the tail
196 * of the list. There is always at least one &struct drbd_tl_epoch object.
198 * Each &struct drbd_tl_epoch has a circular double linked list of requests
201 static int tl_init(struct drbd_tconn *tconn)
203 struct drbd_tl_epoch *b;
205 /* during device minor initialization, we may well use GFP_KERNEL */
206 b = kmalloc(sizeof(struct drbd_tl_epoch), GFP_KERNEL);
209 INIT_LIST_HEAD(&b->requests);
210 INIT_LIST_HEAD(&b->w.list);
214 b->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
216 tconn->oldest_tle = b;
217 tconn->newest_tle = b;
218 INIT_LIST_HEAD(&tconn->out_of_sequence_requests);
223 static void tl_cleanup(struct drbd_tconn *tconn)
225 if (tconn->oldest_tle != tconn->newest_tle)
226 conn_err(tconn, "ASSERT FAILED: oldest_tle == newest_tle\n");
227 if (!list_empty(&tconn->out_of_sequence_requests))
228 conn_err(tconn, "ASSERT FAILED: list_empty(out_of_sequence_requests)\n");
229 kfree(tconn->oldest_tle);
230 tconn->oldest_tle = NULL;
231 kfree(tconn->unused_spare_tle);
232 tconn->unused_spare_tle = NULL;
236 * _tl_add_barrier() - Adds a barrier to the transfer log
237 * @mdev: DRBD device.
238 * @new: Barrier to be added before the current head of the TL.
240 * The caller must hold the req_lock.
242 void _tl_add_barrier(struct drbd_tconn *tconn, struct drbd_tl_epoch *new)
244 struct drbd_tl_epoch *newest_before;
246 INIT_LIST_HEAD(&new->requests);
247 INIT_LIST_HEAD(&new->w.list);
248 new->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
252 newest_before = tconn->newest_tle;
253 /* never send a barrier number == 0, because that is special-cased
254 * when using TCQ for our write ordering code */
255 new->br_number = (newest_before->br_number+1) ?: 1;
256 if (tconn->newest_tle != new) {
257 tconn->newest_tle->next = new;
258 tconn->newest_tle = new;
263 * tl_release() - Free or recycle the oldest &struct drbd_tl_epoch object of the TL
264 * @mdev: DRBD device.
265 * @barrier_nr: Expected identifier of the DRBD write barrier packet.
266 * @set_size: Expected number of requests before that barrier.
268 * In case the passed barrier_nr or set_size does not match the oldest
269 * &struct drbd_tl_epoch objects this function will cause a termination
272 void tl_release(struct drbd_tconn *tconn, unsigned int barrier_nr,
273 unsigned int set_size)
275 struct drbd_conf *mdev;
276 struct drbd_tl_epoch *b, *nob; /* next old barrier */
277 struct list_head *le, *tle;
278 struct drbd_request *r;
280 spin_lock_irq(&tconn->req_lock);
282 b = tconn->oldest_tle;
284 /* first some paranoia code */
286 conn_err(tconn, "BAD! BarrierAck #%u received, but no epoch in tl!?\n",
290 if (b->br_number != barrier_nr) {
291 conn_err(tconn, "BAD! BarrierAck #%u received, expected #%u!\n",
292 barrier_nr, b->br_number);
295 if (b->n_writes != set_size) {
296 conn_err(tconn, "BAD! BarrierAck #%u received with n_writes=%u, expected n_writes=%u!\n",
297 barrier_nr, set_size, b->n_writes);
301 /* Clean up list of requests processed during current epoch */
302 list_for_each_safe(le, tle, &b->requests) {
303 r = list_entry(le, struct drbd_request, tl_requests);
304 _req_mod(r, BARRIER_ACKED);
306 /* There could be requests on the list waiting for completion
307 of the write to the local disk. To avoid corruptions of
308 slab's data structures we have to remove the lists head.
310 Also there could have been a barrier ack out of sequence, overtaking
311 the write acks - which would be a bug and violating write ordering.
312 To not deadlock in case we lose connection while such requests are
313 still pending, we need some way to find them for the
314 _req_mode(CONNECTION_LOST_WHILE_PENDING).
316 These have been list_move'd to the out_of_sequence_requests list in
317 _req_mod(, BARRIER_ACKED) above.
319 list_del_init(&b->requests);
323 if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags)) {
324 _tl_add_barrier(tconn, b);
326 tconn->oldest_tle = nob;
327 /* if nob == NULL b was the only barrier, and becomes the new
328 barrier. Therefore tconn->oldest_tle points already to b */
330 D_ASSERT(nob != NULL);
331 tconn->oldest_tle = nob;
335 spin_unlock_irq(&tconn->req_lock);
336 dec_ap_pending(mdev);
341 spin_unlock_irq(&tconn->req_lock);
342 conn_request_state(tconn, NS(conn, C_PROTOCOL_ERROR), CS_HARD);
347 * _tl_restart() - Walks the transfer log, and applies an action to all requests
348 * @mdev: DRBD device.
349 * @what: The action/event to perform with all request objects
351 * @what might be one of CONNECTION_LOST_WHILE_PENDING, RESEND, FAIL_FROZEN_DISK_IO,
352 * RESTART_FROZEN_DISK_IO.
354 void _tl_restart(struct drbd_tconn *tconn, enum drbd_req_event what)
356 struct drbd_tl_epoch *b, *tmp, **pn;
357 struct list_head *le, *tle, carry_reads;
358 struct drbd_request *req;
359 int rv, n_writes, n_reads;
361 b = tconn->oldest_tle;
362 pn = &tconn->oldest_tle;
366 INIT_LIST_HEAD(&carry_reads);
367 list_for_each_safe(le, tle, &b->requests) {
368 req = list_entry(le, struct drbd_request, tl_requests);
369 rv = _req_mod(req, what);
371 n_writes += (rv & MR_WRITE) >> MR_WRITE_SHIFT;
372 n_reads += (rv & MR_READ) >> MR_READ_SHIFT;
377 if (what == RESEND) {
378 b->n_writes = n_writes;
379 if (b->w.cb == NULL) {
380 b->w.cb = w_send_barrier;
381 inc_ap_pending(b->w.mdev);
382 set_bit(CREATE_BARRIER, &b->w.mdev->flags);
385 drbd_queue_work(&tconn->data.work, &b->w);
390 list_add(&carry_reads, &b->requests);
391 /* there could still be requests on that ring list,
392 * in case local io is still pending */
393 list_del(&b->requests);
395 /* dec_ap_pending corresponding to queue_barrier.
396 * the newest barrier may not have been queued yet,
397 * in which case w.cb is still NULL. */
399 dec_ap_pending(b->w.mdev);
401 if (b == tconn->newest_tle) {
402 /* recycle, but reinit! */
404 conn_err(tconn, "ASSERT FAILED tmp == NULL");
405 INIT_LIST_HEAD(&b->requests);
406 list_splice(&carry_reads, &b->requests);
407 INIT_LIST_HEAD(&b->w.list);
409 b->br_number = net_random();
419 list_splice(&carry_reads, &b->requests);
425 * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL
426 * @mdev: DRBD device.
428 * This is called after the connection to the peer was lost. The storage covered
429 * by the requests on the transfer gets marked as our of sync. Called from the
430 * receiver thread and the worker thread.
432 void tl_clear(struct drbd_tconn *tconn)
434 struct drbd_conf *mdev;
435 struct list_head *le, *tle;
436 struct drbd_request *r;
439 spin_lock_irq(&tconn->req_lock);
441 _tl_restart(tconn, CONNECTION_LOST_WHILE_PENDING);
443 /* we expect this list to be empty. */
444 if (!list_empty(&tconn->out_of_sequence_requests))
445 conn_err(tconn, "ASSERT FAILED list_empty(&out_of_sequence_requests)\n");
447 /* but just in case, clean it up anyways! */
448 list_for_each_safe(le, tle, &tconn->out_of_sequence_requests) {
449 r = list_entry(le, struct drbd_request, tl_requests);
450 /* It would be nice to complete outside of spinlock.
451 * But this is easier for now. */
452 _req_mod(r, CONNECTION_LOST_WHILE_PENDING);
455 /* ensure bit indicating barrier is required is clear */
456 idr_for_each_entry(&tconn->volumes, mdev, vnr)
457 clear_bit(CREATE_BARRIER, &mdev->flags);
459 spin_unlock_irq(&tconn->req_lock);
462 void tl_restart(struct drbd_tconn *tconn, enum drbd_req_event what)
464 spin_lock_irq(&tconn->req_lock);
465 _tl_restart(tconn, what);
466 spin_unlock_irq(&tconn->req_lock);
469 static int drbd_thread_setup(void *arg)
471 struct drbd_thread *thi = (struct drbd_thread *) arg;
472 struct drbd_tconn *tconn = thi->tconn;
476 snprintf(current->comm, sizeof(current->comm), "drbd_%c_%s",
477 thi->name[0], thi->tconn->name);
480 retval = thi->function(thi);
482 spin_lock_irqsave(&thi->t_lock, flags);
484 /* if the receiver has been "EXITING", the last thing it did
485 * was set the conn state to "StandAlone",
486 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
487 * and receiver thread will be "started".
488 * drbd_thread_start needs to set "RESTARTING" in that case.
489 * t_state check and assignment needs to be within the same spinlock,
490 * so either thread_start sees EXITING, and can remap to RESTARTING,
491 * or thread_start see NONE, and can proceed as normal.
494 if (thi->t_state == RESTARTING) {
495 conn_info(tconn, "Restarting %s thread\n", thi->name);
496 thi->t_state = RUNNING;
497 spin_unlock_irqrestore(&thi->t_lock, flags);
504 complete(&thi->stop);
505 spin_unlock_irqrestore(&thi->t_lock, flags);
507 conn_info(tconn, "Terminating %s\n", current->comm);
509 /* Release mod reference taken when thread was started */
510 module_put(THIS_MODULE);
514 static void drbd_thread_init(struct drbd_tconn *tconn, struct drbd_thread *thi,
515 int (*func) (struct drbd_thread *), char *name)
517 spin_lock_init(&thi->t_lock);
520 thi->function = func;
522 strncpy(thi->name, name, ARRAY_SIZE(thi->name));
525 int drbd_thread_start(struct drbd_thread *thi)
527 struct drbd_tconn *tconn = thi->tconn;
528 struct task_struct *nt;
531 /* is used from state engine doing drbd_thread_stop_nowait,
532 * while holding the req lock irqsave */
533 spin_lock_irqsave(&thi->t_lock, flags);
535 switch (thi->t_state) {
537 conn_info(tconn, "Starting %s thread (from %s [%d])\n",
538 thi->name, current->comm, current->pid);
540 /* Get ref on module for thread - this is released when thread exits */
541 if (!try_module_get(THIS_MODULE)) {
542 conn_err(tconn, "Failed to get module reference in drbd_thread_start\n");
543 spin_unlock_irqrestore(&thi->t_lock, flags);
547 init_completion(&thi->stop);
548 thi->reset_cpu_mask = 1;
549 thi->t_state = RUNNING;
550 spin_unlock_irqrestore(&thi->t_lock, flags);
551 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
553 nt = kthread_create(drbd_thread_setup, (void *) thi,
554 "drbd_%c_%s", thi->name[0], thi->tconn->name);
557 conn_err(tconn, "Couldn't start thread\n");
559 module_put(THIS_MODULE);
562 spin_lock_irqsave(&thi->t_lock, flags);
564 thi->t_state = RUNNING;
565 spin_unlock_irqrestore(&thi->t_lock, flags);
569 thi->t_state = RESTARTING;
570 conn_info(tconn, "Restarting %s thread (from %s [%d])\n",
571 thi->name, current->comm, current->pid);
576 spin_unlock_irqrestore(&thi->t_lock, flags);
584 void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
588 enum drbd_thread_state ns = restart ? RESTARTING : EXITING;
590 /* may be called from state engine, holding the req lock irqsave */
591 spin_lock_irqsave(&thi->t_lock, flags);
593 if (thi->t_state == NONE) {
594 spin_unlock_irqrestore(&thi->t_lock, flags);
596 drbd_thread_start(thi);
600 if (thi->t_state != ns) {
601 if (thi->task == NULL) {
602 spin_unlock_irqrestore(&thi->t_lock, flags);
608 init_completion(&thi->stop);
609 if (thi->task != current)
610 force_sig(DRBD_SIGKILL, thi->task);
613 spin_unlock_irqrestore(&thi->t_lock, flags);
616 wait_for_completion(&thi->stop);
619 static struct drbd_thread *drbd_task_to_thread(struct drbd_tconn *tconn, struct task_struct *task)
621 struct drbd_thread *thi =
622 task == tconn->receiver.task ? &tconn->receiver :
623 task == tconn->asender.task ? &tconn->asender :
624 task == tconn->worker.task ? &tconn->worker : NULL;
629 char *drbd_task_to_thread_name(struct drbd_tconn *tconn, struct task_struct *task)
631 struct drbd_thread *thi = drbd_task_to_thread(tconn, task);
632 return thi ? thi->name : task->comm;
635 int conn_lowest_minor(struct drbd_tconn *tconn)
638 struct drbd_conf *mdev;
640 mdev = idr_get_next(&tconn->volumes, &vnr);
643 return mdev_to_minor(mdev);
648 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
649 * @mdev: DRBD device.
651 * Forces all threads of a device onto the same CPU. This is beneficial for
652 * DRBD's performance. May be overwritten by user's configuration.
654 void drbd_calc_cpu_mask(struct drbd_tconn *tconn)
659 if (cpumask_weight(tconn->cpu_mask))
662 ord = conn_lowest_minor(tconn) % cpumask_weight(cpu_online_mask);
663 for_each_online_cpu(cpu) {
665 cpumask_set_cpu(cpu, tconn->cpu_mask);
669 /* should not be reached */
670 cpumask_setall(tconn->cpu_mask);
674 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
675 * @mdev: DRBD device.
676 * @thi: drbd_thread object
678 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
681 void drbd_thread_current_set_cpu(struct drbd_thread *thi)
683 struct task_struct *p = current;
685 if (!thi->reset_cpu_mask)
687 thi->reset_cpu_mask = 0;
688 set_cpus_allowed_ptr(p, thi->tconn->cpu_mask);
692 static void prepare_header80(struct p_header80 *h, enum drbd_packet cmd, int size)
694 h->magic = cpu_to_be32(DRBD_MAGIC);
695 h->command = cpu_to_be16(cmd);
696 h->length = cpu_to_be16(size);
699 static void prepare_header95(struct p_header95 *h, enum drbd_packet cmd, int size)
701 h->magic = cpu_to_be16(DRBD_MAGIC_BIG);
702 h->command = cpu_to_be16(cmd);
703 h->length = cpu_to_be32(size);
706 static void _prepare_header(struct drbd_tconn *tconn, int vnr, struct p_header *h,
707 enum drbd_packet cmd, int size)
709 if (tconn->agreed_pro_version >= 100 || size > DRBD_MAX_SIZE_H80_PACKET)
710 prepare_header95(&h->h95, cmd, size);
712 prepare_header80(&h->h80, cmd, size);
715 static void prepare_header(struct drbd_conf *mdev, struct p_header *h,
716 enum drbd_packet cmd, int size)
718 _prepare_header(mdev->tconn, mdev->vnr, h, cmd, size);
721 /* the appropriate socket mutex must be held already */
722 int _conn_send_cmd(struct drbd_tconn *tconn, int vnr, struct socket *sock,
723 enum drbd_packet cmd, struct p_header *h, size_t size,
728 _prepare_header(tconn, vnr, h, cmd, size - sizeof(struct p_header));
729 err = drbd_send_all(tconn, sock, h, size, msg_flags);
730 if (err && !signal_pending(current))
731 conn_warn(tconn, "short send %s size=%d\n",
732 cmdname(cmd), (int)size);
736 /* don't pass the socket. we may only look at it
737 * when we hold the appropriate socket mutex.
739 int conn_send_cmd(struct drbd_tconn *tconn, int vnr, struct drbd_socket *sock,
740 enum drbd_packet cmd, struct p_header *h, size_t size)
744 mutex_lock(&sock->mutex);
746 err = _conn_send_cmd(tconn, vnr, sock->socket, cmd, h, size, 0);
747 mutex_unlock(&sock->mutex);
751 int conn_send_cmd2(struct drbd_tconn *tconn, enum drbd_packet cmd, char *data,
757 prepare_header80(&h, cmd, size);
758 err = drbd_get_data_sock(tconn);
760 err = drbd_send_all(tconn, tconn->data.socket, &h, sizeof(h), 0);
762 err = drbd_send_all(tconn, tconn->data.socket, data, size, 0);
763 drbd_put_data_sock(tconn);
768 int drbd_send_sync_param(struct drbd_conf *mdev)
770 struct p_rs_param_95 *p;
773 const int apv = mdev->tconn->agreed_pro_version;
775 size = apv <= 87 ? sizeof(struct p_rs_param)
776 : apv == 88 ? sizeof(struct p_rs_param)
777 + strlen(mdev->tconn->net_conf->verify_alg) + 1
778 : apv <= 94 ? sizeof(struct p_rs_param_89)
779 : /* apv >= 95 */ sizeof(struct p_rs_param_95);
781 /* used from admin command context and receiver/worker context.
782 * to avoid kmalloc, grab the socket right here,
783 * then use the pre-allocated sbuf there */
784 mutex_lock(&mdev->tconn->data.mutex);
785 sock = mdev->tconn->data.socket;
787 if (likely(sock != NULL)) {
788 enum drbd_packet cmd =
789 apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
791 p = &mdev->tconn->data.sbuf.rs_param_95;
793 /* initialize verify_alg and csums_alg */
794 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
796 if (get_ldev(mdev)) {
797 p->rate = cpu_to_be32(mdev->ldev->dc.resync_rate);
798 p->c_plan_ahead = cpu_to_be32(mdev->ldev->dc.c_plan_ahead);
799 p->c_delay_target = cpu_to_be32(mdev->ldev->dc.c_delay_target);
800 p->c_fill_target = cpu_to_be32(mdev->ldev->dc.c_fill_target);
801 p->c_max_rate = cpu_to_be32(mdev->ldev->dc.c_max_rate);
804 p->rate = cpu_to_be32(DRBD_RATE_DEF);
805 p->c_plan_ahead = cpu_to_be32(DRBD_C_PLAN_AHEAD_DEF);
806 p->c_delay_target = cpu_to_be32(DRBD_C_DELAY_TARGET_DEF);
807 p->c_fill_target = cpu_to_be32(DRBD_C_FILL_TARGET_DEF);
808 p->c_max_rate = cpu_to_be32(DRBD_C_MAX_RATE_DEF);
812 strcpy(p->verify_alg, mdev->tconn->net_conf->verify_alg);
814 strcpy(p->csums_alg, mdev->tconn->net_conf->csums_alg);
816 err = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
820 mutex_unlock(&mdev->tconn->data.mutex);
825 int drbd_send_protocol(struct drbd_tconn *tconn)
827 struct p_protocol *p;
830 size = sizeof(struct p_protocol);
832 if (tconn->agreed_pro_version >= 87)
833 size += strlen(tconn->net_conf->integrity_alg) + 1;
835 /* we must not recurse into our own queue,
836 * as that is blocked during handshake */
837 p = kmalloc(size, GFP_NOIO);
841 p->protocol = cpu_to_be32(tconn->net_conf->wire_protocol);
842 p->after_sb_0p = cpu_to_be32(tconn->net_conf->after_sb_0p);
843 p->after_sb_1p = cpu_to_be32(tconn->net_conf->after_sb_1p);
844 p->after_sb_2p = cpu_to_be32(tconn->net_conf->after_sb_2p);
845 p->two_primaries = cpu_to_be32(tconn->net_conf->two_primaries);
848 if (tconn->net_conf->want_lose)
850 if (tconn->net_conf->dry_run) {
851 if (tconn->agreed_pro_version >= 92)
854 conn_err(tconn, "--dry-run is not supported by peer");
859 p->conn_flags = cpu_to_be32(cf);
861 if (tconn->agreed_pro_version >= 87)
862 strcpy(p->integrity_alg, tconn->net_conf->integrity_alg);
864 err = conn_send_cmd2(tconn, P_PROTOCOL, p->head.payload, size - sizeof(struct p_header));
869 int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
874 if (!get_ldev_if_state(mdev, D_NEGOTIATING))
877 for (i = UI_CURRENT; i < UI_SIZE; i++)
878 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
880 mdev->comm_bm_set = drbd_bm_total_weight(mdev);
881 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
882 uuid_flags |= mdev->tconn->net_conf->want_lose ? 1 : 0;
883 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
884 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
885 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
889 return drbd_send_cmd(mdev, &mdev->tconn->data, P_UUIDS, &p.head, sizeof(p));
892 int drbd_send_uuids(struct drbd_conf *mdev)
894 return _drbd_send_uuids(mdev, 0);
897 int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
899 return _drbd_send_uuids(mdev, 8);
902 void drbd_print_uuids(struct drbd_conf *mdev, const char *text)
904 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
905 u64 *uuid = mdev->ldev->md.uuid;
906 dev_info(DEV, "%s %016llX:%016llX:%016llX:%016llX\n",
908 (unsigned long long)uuid[UI_CURRENT],
909 (unsigned long long)uuid[UI_BITMAP],
910 (unsigned long long)uuid[UI_HISTORY_START],
911 (unsigned long long)uuid[UI_HISTORY_END]);
914 dev_info(DEV, "%s effective data uuid: %016llX\n",
916 (unsigned long long)mdev->ed_uuid);
920 void drbd_gen_and_send_sync_uuid(struct drbd_conf *mdev)
925 D_ASSERT(mdev->state.disk == D_UP_TO_DATE);
927 uuid = mdev->ldev->md.uuid[UI_BITMAP] + UUID_NEW_BM_OFFSET;
928 drbd_uuid_set(mdev, UI_BITMAP, uuid);
929 drbd_print_uuids(mdev, "updated sync UUID");
931 p.uuid = cpu_to_be64(uuid);
933 drbd_send_cmd(mdev, &mdev->tconn->data, P_SYNC_UUID, &p.head, sizeof(p));
936 int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags)
939 sector_t d_size, u_size;
940 int q_order_type, max_bio_size;
942 if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
943 D_ASSERT(mdev->ldev->backing_bdev);
944 d_size = drbd_get_max_capacity(mdev->ldev);
945 u_size = mdev->ldev->dc.disk_size;
946 q_order_type = drbd_queue_order_type(mdev);
947 max_bio_size = queue_max_hw_sectors(mdev->ldev->backing_bdev->bd_disk->queue) << 9;
948 max_bio_size = min_t(int, max_bio_size, DRBD_MAX_BIO_SIZE);
953 q_order_type = QUEUE_ORDERED_NONE;
954 max_bio_size = DRBD_MAX_BIO_SIZE; /* ... multiple BIOs per peer_request */
957 p.d_size = cpu_to_be64(d_size);
958 p.u_size = cpu_to_be64(u_size);
959 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
960 p.max_bio_size = cpu_to_be32(max_bio_size);
961 p.queue_order_type = cpu_to_be16(q_order_type);
962 p.dds_flags = cpu_to_be16(flags);
964 return drbd_send_cmd(mdev, &mdev->tconn->data, P_SIZES, &p.head, sizeof(p));
968 * drbd_send_state() - Sends the drbd state to the peer
969 * @mdev: DRBD device.
971 int drbd_send_state(struct drbd_conf *mdev)
977 mutex_lock(&mdev->tconn->data.mutex);
979 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
980 sock = mdev->tconn->data.socket;
982 if (likely(sock != NULL))
983 err = _drbd_send_cmd(mdev, sock, P_STATE, &p.head, sizeof(p), 0);
985 mutex_unlock(&mdev->tconn->data.mutex);
990 int _conn_send_state_req(struct drbd_tconn *tconn, int vnr, enum drbd_packet cmd,
991 union drbd_state mask, union drbd_state val)
993 struct p_req_state p;
995 p.mask = cpu_to_be32(mask.i);
996 p.val = cpu_to_be32(val.i);
998 return conn_send_cmd(tconn, vnr, &tconn->data, cmd, &p.head, sizeof(p));
1001 void drbd_send_sr_reply(struct drbd_conf *mdev, enum drbd_state_rv retcode)
1003 struct p_req_state_reply p;
1005 p.retcode = cpu_to_be32(retcode);
1007 drbd_send_cmd(mdev, &mdev->tconn->meta, P_STATE_CHG_REPLY, &p.head, sizeof(p));
1010 int conn_send_sr_reply(struct drbd_tconn *tconn, enum drbd_state_rv retcode)
1012 struct p_req_state_reply p;
1013 enum drbd_packet cmd = tconn->agreed_pro_version < 100 ? P_STATE_CHG_REPLY : P_CONN_ST_CHG_REPLY;
1015 p.retcode = cpu_to_be32(retcode);
1017 return !conn_send_cmd(tconn, 0, &tconn->meta, cmd, &p.head, sizeof(p));
1020 int fill_bitmap_rle_bits(struct drbd_conf *mdev,
1021 struct p_compressed_bm *p,
1022 struct bm_xfer_ctx *c)
1024 struct bitstream bs;
1025 unsigned long plain_bits;
1032 /* may we use this feature? */
1033 if ((mdev->tconn->net_conf->use_rle == 0) ||
1034 (mdev->tconn->agreed_pro_version < 90))
1037 if (c->bit_offset >= c->bm_bits)
1038 return 0; /* nothing to do. */
1040 /* use at most thus many bytes */
1041 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
1042 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
1043 /* plain bits covered in this code string */
1046 /* p->encoding & 0x80 stores whether the first run length is set.
1047 * bit offset is implicit.
1048 * start with toggle == 2 to be able to tell the first iteration */
1051 /* see how much plain bits we can stuff into one packet
1052 * using RLE and VLI. */
1054 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
1055 : _drbd_bm_find_next(mdev, c->bit_offset);
1058 rl = tmp - c->bit_offset;
1060 if (toggle == 2) { /* first iteration */
1062 /* the first checked bit was set,
1063 * store start value, */
1064 DCBP_set_start(p, 1);
1065 /* but skip encoding of zero run length */
1069 DCBP_set_start(p, 0);
1072 /* paranoia: catch zero runlength.
1073 * can only happen if bitmap is modified while we scan it. */
1075 dev_err(DEV, "unexpected zero runlength while encoding bitmap "
1076 "t:%u bo:%lu\n", toggle, c->bit_offset);
1080 bits = vli_encode_bits(&bs, rl);
1081 if (bits == -ENOBUFS) /* buffer full */
1084 dev_err(DEV, "error while encoding bitmap: %d\n", bits);
1090 c->bit_offset = tmp;
1091 } while (c->bit_offset < c->bm_bits);
1093 len = bs.cur.b - p->code + !!bs.cur.bit;
1095 if (plain_bits < (len << 3)) {
1096 /* incompressible with this method.
1097 * we need to rewind both word and bit position. */
1098 c->bit_offset -= plain_bits;
1099 bm_xfer_ctx_bit_to_word_offset(c);
1100 c->bit_offset = c->word_offset * BITS_PER_LONG;
1104 /* RLE + VLI was able to compress it just fine.
1105 * update c->word_offset. */
1106 bm_xfer_ctx_bit_to_word_offset(c);
1108 /* store pad_bits */
1109 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
1115 * send_bitmap_rle_or_plain
1117 * Return 0 when done, 1 when another iteration is needed, and a negative error
1118 * code upon failure.
1121 send_bitmap_rle_or_plain(struct drbd_conf *mdev,
1122 struct p_header *h, struct bm_xfer_ctx *c)
1124 struct p_compressed_bm *p = (void*)h;
1125 unsigned long num_words;
1129 len = fill_bitmap_rle_bits(mdev, p, c);
1135 DCBP_set_code(p, RLE_VLI_Bits);
1136 ok = !_drbd_send_cmd(mdev, mdev->tconn->data.socket, P_COMPRESSED_BITMAP, h,
1137 sizeof(*p) + len, 0);
1140 c->bytes[0] += sizeof(*p) + len;
1142 if (c->bit_offset >= c->bm_bits)
1145 /* was not compressible.
1146 * send a buffer full of plain text bits instead. */
1147 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
1148 len = num_words * sizeof(long);
1150 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
1151 ok = !_drbd_send_cmd(mdev, mdev->tconn->data.socket, P_BITMAP,
1152 h, sizeof(struct p_header80) + len, 0);
1153 c->word_offset += num_words;
1154 c->bit_offset = c->word_offset * BITS_PER_LONG;
1157 c->bytes[1] += sizeof(struct p_header80) + len;
1159 if (c->bit_offset > c->bm_bits)
1160 c->bit_offset = c->bm_bits;
1164 INFO_bm_xfer_stats(mdev, "send", c);
1172 /* See the comment at receive_bitmap() */
1173 int _drbd_send_bitmap(struct drbd_conf *mdev)
1175 struct bm_xfer_ctx c;
1179 if (!expect(mdev->bitmap))
1182 /* maybe we should use some per thread scratch page,
1183 * and allocate that during initial device creation? */
1184 p = (struct p_header *) __get_free_page(GFP_NOIO);
1186 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
1190 if (get_ldev(mdev)) {
1191 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
1192 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
1193 drbd_bm_set_all(mdev);
1194 if (drbd_bm_write(mdev)) {
1195 /* write_bm did fail! Leave full sync flag set in Meta P_DATA
1196 * but otherwise process as per normal - need to tell other
1197 * side that a full resync is required! */
1198 dev_err(DEV, "Failed to write bitmap to disk!\n");
1200 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
1207 c = (struct bm_xfer_ctx) {
1208 .bm_bits = drbd_bm_bits(mdev),
1209 .bm_words = drbd_bm_words(mdev),
1213 err = send_bitmap_rle_or_plain(mdev, p, &c);
1216 free_page((unsigned long) p);
1220 int drbd_send_bitmap(struct drbd_conf *mdev)
1224 if (drbd_get_data_sock(mdev->tconn))
1226 err = !_drbd_send_bitmap(mdev);
1227 drbd_put_data_sock(mdev->tconn);
1230 void drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
1232 struct p_barrier_ack p;
1234 p.barrier = barrier_nr;
1235 p.set_size = cpu_to_be32(set_size);
1237 if (mdev->state.conn >= C_CONNECTED)
1238 drbd_send_cmd(mdev, &mdev->tconn->meta, P_BARRIER_ACK, &p.head, sizeof(p));
1242 * _drbd_send_ack() - Sends an ack packet
1243 * @mdev: DRBD device.
1244 * @cmd: Packet command code.
1245 * @sector: sector, needs to be in big endian byte order
1246 * @blksize: size in byte, needs to be in big endian byte order
1247 * @block_id: Id, big endian byte order
1249 static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packet cmd,
1250 u64 sector, u32 blksize, u64 block_id)
1252 struct p_block_ack p;
1255 p.block_id = block_id;
1256 p.blksize = blksize;
1257 p.seq_num = cpu_to_be32(atomic_inc_return(&mdev->packet_seq));
1259 if (!mdev->tconn->meta.socket || mdev->state.conn < C_CONNECTED)
1261 return drbd_send_cmd(mdev, &mdev->tconn->meta, cmd, &p.head, sizeof(p));
1264 /* dp->sector and dp->block_id already/still in network byte order,
1265 * data_size is payload size according to dp->head,
1266 * and may need to be corrected for digest size. */
1267 void drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packet cmd,
1268 struct p_data *dp, int data_size)
1270 data_size -= (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_r_tfm) ?
1271 crypto_hash_digestsize(mdev->tconn->integrity_r_tfm) : 0;
1272 _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
1276 void drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packet cmd,
1277 struct p_block_req *rp)
1279 _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
1283 * drbd_send_ack() - Sends an ack packet
1284 * @mdev: DRBD device
1285 * @cmd: packet command code
1286 * @peer_req: peer request
1288 int drbd_send_ack(struct drbd_conf *mdev, enum drbd_packet cmd,
1289 struct drbd_peer_request *peer_req)
1291 return _drbd_send_ack(mdev, cmd,
1292 cpu_to_be64(peer_req->i.sector),
1293 cpu_to_be32(peer_req->i.size),
1294 peer_req->block_id);
1297 /* This function misuses the block_id field to signal if the blocks
1298 * are is sync or not. */
1299 int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packet cmd,
1300 sector_t sector, int blksize, u64 block_id)
1302 return _drbd_send_ack(mdev, cmd,
1303 cpu_to_be64(sector),
1304 cpu_to_be32(blksize),
1305 cpu_to_be64(block_id));
1308 int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
1309 sector_t sector, int size, u64 block_id)
1311 struct p_block_req p;
1313 p.sector = cpu_to_be64(sector);
1314 p.block_id = block_id;
1315 p.blksize = cpu_to_be32(size);
1317 return drbd_send_cmd(mdev, &mdev->tconn->data, cmd, &p.head, sizeof(p));
1320 int drbd_send_drequest_csum(struct drbd_conf *mdev, sector_t sector, int size,
1321 void *digest, int digest_size, enum drbd_packet cmd)
1324 struct p_block_req p;
1326 prepare_header(mdev, &p.head, cmd, sizeof(p) - sizeof(struct p_header) + digest_size);
1327 p.sector = cpu_to_be64(sector);
1328 p.block_id = ID_SYNCER /* unused */;
1329 p.blksize = cpu_to_be32(size);
1331 mutex_lock(&mdev->tconn->data.mutex);
1332 err = drbd_send_all(mdev->tconn, mdev->tconn->data.socket, &p, sizeof(p), 0);
1334 err = drbd_send_all(mdev->tconn, mdev->tconn->data.socket, digest, digest_size, 0);
1335 mutex_unlock(&mdev->tconn->data.mutex);
1339 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
1341 struct p_block_req p;
1343 p.sector = cpu_to_be64(sector);
1344 p.block_id = ID_SYNCER /* unused */;
1345 p.blksize = cpu_to_be32(size);
1347 return drbd_send_cmd(mdev, &mdev->tconn->data, P_OV_REQUEST, &p.head, sizeof(p));
1350 /* called on sndtimeo
1351 * returns false if we should retry,
1352 * true if we think connection is dead
1354 static int we_should_drop_the_connection(struct drbd_tconn *tconn, struct socket *sock)
1357 /* long elapsed = (long)(jiffies - mdev->last_received); */
1359 drop_it = tconn->meta.socket == sock
1360 || !tconn->asender.task
1361 || get_t_state(&tconn->asender) != RUNNING
1362 || tconn->cstate < C_WF_REPORT_PARAMS;
1367 drop_it = !--tconn->ko_count;
1369 conn_err(tconn, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
1370 current->comm, current->pid, tconn->ko_count);
1371 request_ping(tconn);
1374 return drop_it; /* && (mdev->state == R_PRIMARY) */;
1377 static void drbd_update_congested(struct drbd_tconn *tconn)
1379 struct sock *sk = tconn->data.socket->sk;
1380 if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5)
1381 set_bit(NET_CONGESTED, &tconn->flags);
1384 /* The idea of sendpage seems to be to put some kind of reference
1385 * to the page into the skb, and to hand it over to the NIC. In
1386 * this process get_page() gets called.
1388 * As soon as the page was really sent over the network put_page()
1389 * gets called by some part of the network layer. [ NIC driver? ]
1391 * [ get_page() / put_page() increment/decrement the count. If count
1392 * reaches 0 the page will be freed. ]
1394 * This works nicely with pages from FSs.
1395 * But this means that in protocol A we might signal IO completion too early!
1397 * In order not to corrupt data during a resync we must make sure
1398 * that we do not reuse our own buffer pages (EEs) to early, therefore
1399 * we have the net_ee list.
1401 * XFS seems to have problems, still, it submits pages with page_count == 0!
1402 * As a workaround, we disable sendpage on pages
1403 * with page_count == 0 or PageSlab.
1405 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
1406 int offset, size_t size, unsigned msg_flags)
1408 struct socket *socket;
1412 socket = mdev->tconn->data.socket;
1413 addr = kmap(page) + offset;
1414 err = drbd_send_all(mdev->tconn, socket, addr, size, msg_flags);
1417 mdev->send_cnt += size >> 9;
1421 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
1422 int offset, size_t size, unsigned msg_flags)
1424 struct socket *socket = mdev->tconn->data.socket;
1425 mm_segment_t oldfs = get_fs();
1429 /* e.g. XFS meta- & log-data is in slab pages, which have a
1430 * page_count of 0 and/or have PageSlab() set.
1431 * we cannot use send_page for those, as that does get_page();
1432 * put_page(); and would cause either a VM_BUG directly, or
1433 * __page_cache_release a page that would actually still be referenced
1434 * by someone, leading to some obscure delayed Oops somewhere else. */
1435 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
1436 return _drbd_no_send_page(mdev, page, offset, size, msg_flags);
1438 msg_flags |= MSG_NOSIGNAL;
1439 drbd_update_congested(mdev->tconn);
1444 sent = socket->ops->sendpage(socket, page, offset, len, msg_flags);
1446 if (sent == -EAGAIN) {
1447 if (we_should_drop_the_connection(mdev->tconn, socket))
1451 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
1452 __func__, (int)size, len, sent);
1459 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
1461 clear_bit(NET_CONGESTED, &mdev->tconn->flags);
1465 mdev->send_cnt += size >> 9;
1470 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
1472 struct bio_vec *bvec;
1474 /* hint all but last page with MSG_MORE */
1475 __bio_for_each_segment(bvec, bio, i, 0) {
1478 err = _drbd_no_send_page(mdev, bvec->bv_page,
1479 bvec->bv_offset, bvec->bv_len,
1480 i == bio->bi_vcnt - 1 ? 0 : MSG_MORE);
1487 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
1489 struct bio_vec *bvec;
1491 /* hint all but last page with MSG_MORE */
1492 __bio_for_each_segment(bvec, bio, i, 0) {
1495 err = _drbd_send_page(mdev, bvec->bv_page,
1496 bvec->bv_offset, bvec->bv_len,
1497 i == bio->bi_vcnt - 1 ? 0 : MSG_MORE);
1504 static int _drbd_send_zc_ee(struct drbd_conf *mdev,
1505 struct drbd_peer_request *peer_req)
1507 struct page *page = peer_req->pages;
1508 unsigned len = peer_req->i.size;
1511 /* hint all but last page with MSG_MORE */
1512 page_chain_for_each(page) {
1513 unsigned l = min_t(unsigned, len, PAGE_SIZE);
1515 err = _drbd_send_page(mdev, page, 0, l,
1516 page_chain_next(page) ? MSG_MORE : 0);
1524 static u32 bio_flags_to_wire(struct drbd_conf *mdev, unsigned long bi_rw)
1526 if (mdev->tconn->agreed_pro_version >= 95)
1527 return (bi_rw & REQ_SYNC ? DP_RW_SYNC : 0) |
1528 (bi_rw & REQ_FUA ? DP_FUA : 0) |
1529 (bi_rw & REQ_FLUSH ? DP_FLUSH : 0) |
1530 (bi_rw & REQ_DISCARD ? DP_DISCARD : 0);
1532 return bi_rw & REQ_SYNC ? DP_RW_SYNC : 0;
1535 /* Used to send write requests
1536 * R_PRIMARY -> Peer (P_DATA)
1538 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
1542 unsigned int dp_flags = 0;
1546 if (drbd_get_data_sock(mdev->tconn))
1549 dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_w_tfm) ?
1550 crypto_hash_digestsize(mdev->tconn->integrity_w_tfm) : 0;
1552 prepare_header(mdev, &p.head, P_DATA, sizeof(p) - sizeof(struct p_header) + dgs + req->i.size);
1553 p.sector = cpu_to_be64(req->i.sector);
1554 p.block_id = (unsigned long)req;
1555 p.seq_num = cpu_to_be32(req->seq_num = atomic_inc_return(&mdev->packet_seq));
1557 dp_flags = bio_flags_to_wire(mdev, req->master_bio->bi_rw);
1559 if (mdev->state.conn >= C_SYNC_SOURCE &&
1560 mdev->state.conn <= C_PAUSED_SYNC_T)
1561 dp_flags |= DP_MAY_SET_IN_SYNC;
1563 p.dp_flags = cpu_to_be32(dp_flags);
1564 set_bit(UNPLUG_REMOTE, &mdev->flags);
1566 drbd_send(mdev->tconn, mdev->tconn->data.socket, &p, sizeof(p), dgs ? MSG_MORE : 0));
1568 dgb = mdev->tconn->int_dig_out;
1569 drbd_csum_bio(mdev, mdev->tconn->integrity_w_tfm, req->master_bio, dgb);
1570 ok = dgs == drbd_send(mdev->tconn, mdev->tconn->data.socket, dgb, dgs, 0);
1573 /* For protocol A, we have to memcpy the payload into
1574 * socket buffers, as we may complete right away
1575 * as soon as we handed it over to tcp, at which point the data
1576 * pages may become invalid.
1578 * For data-integrity enabled, we copy it as well, so we can be
1579 * sure that even if the bio pages may still be modified, it
1580 * won't change the data on the wire, thus if the digest checks
1581 * out ok after sending on this side, but does not fit on the
1582 * receiving side, we sure have detected corruption elsewhere.
1584 if (mdev->tconn->net_conf->wire_protocol == DRBD_PROT_A || dgs)
1585 ok = !_drbd_send_bio(mdev, req->master_bio);
1587 ok = !_drbd_send_zc_bio(mdev, req->master_bio);
1589 /* double check digest, sometimes buffers have been modified in flight. */
1590 if (dgs > 0 && dgs <= 64) {
1591 /* 64 byte, 512 bit, is the largest digest size
1592 * currently supported in kernel crypto. */
1593 unsigned char digest[64];
1594 drbd_csum_bio(mdev, mdev->tconn->integrity_w_tfm, req->master_bio, digest);
1595 if (memcmp(mdev->tconn->int_dig_out, digest, dgs)) {
1597 "Digest mismatch, buffer modified by upper layers during write: %llus +%u\n",
1598 (unsigned long long)req->i.sector, req->i.size);
1600 } /* else if (dgs > 64) {
1601 ... Be noisy about digest too large ...
1605 drbd_put_data_sock(mdev->tconn);
1610 /* answer packet, used to send data back for read requests:
1611 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
1612 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
1614 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packet cmd,
1615 struct drbd_peer_request *peer_req)
1622 dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_w_tfm) ?
1623 crypto_hash_digestsize(mdev->tconn->integrity_w_tfm) : 0;
1625 prepare_header(mdev, &p.head, cmd, sizeof(p) -
1626 sizeof(struct p_header80) +
1627 dgs + peer_req->i.size);
1628 p.sector = cpu_to_be64(peer_req->i.sector);
1629 p.block_id = peer_req->block_id;
1630 p.seq_num = 0; /* unused */
1632 /* Only called by our kernel thread.
1633 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
1634 * in response to admin command or module unload.
1636 err = drbd_get_data_sock(mdev->tconn);
1639 err = drbd_send_all(mdev->tconn, mdev->tconn->data.socket, &p,
1640 sizeof(p), dgs ? MSG_MORE : 0);
1642 dgb = mdev->tconn->int_dig_out;
1643 drbd_csum_ee(mdev, mdev->tconn->integrity_w_tfm, peer_req, dgb);
1644 err = drbd_send_all(mdev->tconn, mdev->tconn->data.socket, dgb,
1648 err = _drbd_send_zc_ee(mdev, peer_req);
1649 drbd_put_data_sock(mdev->tconn);
1654 int drbd_send_oos(struct drbd_conf *mdev, struct drbd_request *req)
1656 struct p_block_desc p;
1658 p.sector = cpu_to_be64(req->i.sector);
1659 p.blksize = cpu_to_be32(req->i.size);
1661 return drbd_send_cmd(mdev, &mdev->tconn->data, P_OUT_OF_SYNC, &p.head, sizeof(p));
1665 drbd_send distinguishes two cases:
1667 Packets sent via the data socket "sock"
1668 and packets sent via the meta data socket "msock"
1671 -----------------+-------------------------+------------------------------
1672 timeout conf.timeout / 2 conf.timeout / 2
1673 timeout action send a ping via msock Abort communication
1674 and close all sockets
1678 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
1680 int drbd_send(struct drbd_tconn *tconn, struct socket *sock,
1681 void *buf, size_t size, unsigned msg_flags)
1690 /* THINK if (signal_pending) return ... ? */
1695 msg.msg_name = NULL;
1696 msg.msg_namelen = 0;
1697 msg.msg_control = NULL;
1698 msg.msg_controllen = 0;
1699 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
1701 if (sock == tconn->data.socket) {
1702 tconn->ko_count = tconn->net_conf->ko_count;
1703 drbd_update_congested(tconn);
1707 * tcp_sendmsg does _not_ use its size parameter at all ?
1709 * -EAGAIN on timeout, -EINTR on signal.
1712 * do we need to block DRBD_SIG if sock == &meta.socket ??
1713 * otherwise wake_asender() might interrupt some send_*Ack !
1715 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
1716 if (rv == -EAGAIN) {
1717 if (we_should_drop_the_connection(tconn, sock))
1723 flush_signals(current);
1731 } while (sent < size);
1733 if (sock == tconn->data.socket)
1734 clear_bit(NET_CONGESTED, &tconn->flags);
1737 if (rv != -EAGAIN) {
1738 conn_err(tconn, "%s_sendmsg returned %d\n",
1739 sock == tconn->meta.socket ? "msock" : "sock",
1741 conn_request_state(tconn, NS(conn, C_BROKEN_PIPE), CS_HARD);
1743 conn_request_state(tconn, NS(conn, C_TIMEOUT), CS_HARD);
1750 * drbd_send_all - Send an entire buffer
1752 * Returns 0 upon success and a negative error value otherwise.
1754 int drbd_send_all(struct drbd_tconn *tconn, struct socket *sock, void *buffer,
1755 size_t size, unsigned msg_flags)
1759 err = drbd_send(tconn, sock, buffer, size, msg_flags);
1767 static int drbd_open(struct block_device *bdev, fmode_t mode)
1769 struct drbd_conf *mdev = bdev->bd_disk->private_data;
1770 unsigned long flags;
1773 mutex_lock(&drbd_main_mutex);
1774 spin_lock_irqsave(&mdev->tconn->req_lock, flags);
1775 /* to have a stable mdev->state.role
1776 * and no race with updating open_cnt */
1778 if (mdev->state.role != R_PRIMARY) {
1779 if (mode & FMODE_WRITE)
1781 else if (!allow_oos)
1787 spin_unlock_irqrestore(&mdev->tconn->req_lock, flags);
1788 mutex_unlock(&drbd_main_mutex);
1793 static int drbd_release(struct gendisk *gd, fmode_t mode)
1795 struct drbd_conf *mdev = gd->private_data;
1796 mutex_lock(&drbd_main_mutex);
1798 mutex_unlock(&drbd_main_mutex);
1802 static void drbd_set_defaults(struct drbd_conf *mdev)
1804 /* Beware! The actual layout differs
1805 * between big endian and little endian */
1806 mdev->state = (union drbd_state) {
1807 { .role = R_SECONDARY,
1809 .conn = C_STANDALONE,
1818 void drbd_init_set_defaults(struct drbd_conf *mdev)
1820 /* the memset(,0,) did most of this.
1821 * note: only assignments, no allocation in here */
1823 drbd_set_defaults(mdev);
1825 atomic_set(&mdev->ap_bio_cnt, 0);
1826 atomic_set(&mdev->ap_pending_cnt, 0);
1827 atomic_set(&mdev->rs_pending_cnt, 0);
1828 atomic_set(&mdev->unacked_cnt, 0);
1829 atomic_set(&mdev->local_cnt, 0);
1830 atomic_set(&mdev->pp_in_use, 0);
1831 atomic_set(&mdev->pp_in_use_by_net, 0);
1832 atomic_set(&mdev->rs_sect_in, 0);
1833 atomic_set(&mdev->rs_sect_ev, 0);
1834 atomic_set(&mdev->ap_in_flight, 0);
1836 mutex_init(&mdev->md_io_mutex);
1837 mutex_init(&mdev->own_state_mutex);
1838 mdev->state_mutex = &mdev->own_state_mutex;
1840 spin_lock_init(&mdev->al_lock);
1841 spin_lock_init(&mdev->peer_seq_lock);
1842 spin_lock_init(&mdev->epoch_lock);
1844 INIT_LIST_HEAD(&mdev->active_ee);
1845 INIT_LIST_HEAD(&mdev->sync_ee);
1846 INIT_LIST_HEAD(&mdev->done_ee);
1847 INIT_LIST_HEAD(&mdev->read_ee);
1848 INIT_LIST_HEAD(&mdev->net_ee);
1849 INIT_LIST_HEAD(&mdev->resync_reads);
1850 INIT_LIST_HEAD(&mdev->resync_work.list);
1851 INIT_LIST_HEAD(&mdev->unplug_work.list);
1852 INIT_LIST_HEAD(&mdev->go_diskless.list);
1853 INIT_LIST_HEAD(&mdev->md_sync_work.list);
1854 INIT_LIST_HEAD(&mdev->start_resync_work.list);
1855 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
1857 mdev->resync_work.cb = w_resync_timer;
1858 mdev->unplug_work.cb = w_send_write_hint;
1859 mdev->go_diskless.cb = w_go_diskless;
1860 mdev->md_sync_work.cb = w_md_sync;
1861 mdev->bm_io_work.w.cb = w_bitmap_io;
1862 mdev->start_resync_work.cb = w_start_resync;
1864 mdev->resync_work.mdev = mdev;
1865 mdev->unplug_work.mdev = mdev;
1866 mdev->go_diskless.mdev = mdev;
1867 mdev->md_sync_work.mdev = mdev;
1868 mdev->bm_io_work.w.mdev = mdev;
1869 mdev->start_resync_work.mdev = mdev;
1871 init_timer(&mdev->resync_timer);
1872 init_timer(&mdev->md_sync_timer);
1873 init_timer(&mdev->start_resync_timer);
1874 init_timer(&mdev->request_timer);
1875 mdev->resync_timer.function = resync_timer_fn;
1876 mdev->resync_timer.data = (unsigned long) mdev;
1877 mdev->md_sync_timer.function = md_sync_timer_fn;
1878 mdev->md_sync_timer.data = (unsigned long) mdev;
1879 mdev->start_resync_timer.function = start_resync_timer_fn;
1880 mdev->start_resync_timer.data = (unsigned long) mdev;
1881 mdev->request_timer.function = request_timer_fn;
1882 mdev->request_timer.data = (unsigned long) mdev;
1884 init_waitqueue_head(&mdev->misc_wait);
1885 init_waitqueue_head(&mdev->state_wait);
1886 init_waitqueue_head(&mdev->ee_wait);
1887 init_waitqueue_head(&mdev->al_wait);
1888 init_waitqueue_head(&mdev->seq_wait);
1890 /* mdev->tconn->agreed_pro_version gets initialized in drbd_connect() */
1891 mdev->write_ordering = WO_bdev_flush;
1892 mdev->resync_wenr = LC_FREE;
1893 mdev->peer_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
1894 mdev->local_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
1897 void drbd_mdev_cleanup(struct drbd_conf *mdev)
1900 if (mdev->tconn->receiver.t_state != NONE)
1901 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
1902 mdev->tconn->receiver.t_state);
1904 /* no need to lock it, I'm the only thread alive */
1905 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
1906 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
1916 mdev->rs_failed = 0;
1917 mdev->rs_last_events = 0;
1918 mdev->rs_last_sect_ev = 0;
1919 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
1920 mdev->rs_mark_left[i] = 0;
1921 mdev->rs_mark_time[i] = 0;
1923 D_ASSERT(mdev->tconn->net_conf == NULL);
1925 drbd_set_my_capacity(mdev, 0);
1927 /* maybe never allocated. */
1928 drbd_bm_resize(mdev, 0, 1);
1929 drbd_bm_cleanup(mdev);
1932 drbd_free_resources(mdev);
1933 clear_bit(AL_SUSPENDED, &mdev->flags);
1936 * currently we drbd_init_ee only on module load, so
1937 * we may do drbd_release_ee only on module unload!
1939 D_ASSERT(list_empty(&mdev->active_ee));
1940 D_ASSERT(list_empty(&mdev->sync_ee));
1941 D_ASSERT(list_empty(&mdev->done_ee));
1942 D_ASSERT(list_empty(&mdev->read_ee));
1943 D_ASSERT(list_empty(&mdev->net_ee));
1944 D_ASSERT(list_empty(&mdev->resync_reads));
1945 D_ASSERT(list_empty(&mdev->tconn->data.work.q));
1946 D_ASSERT(list_empty(&mdev->tconn->meta.work.q));
1947 D_ASSERT(list_empty(&mdev->resync_work.list));
1948 D_ASSERT(list_empty(&mdev->unplug_work.list));
1949 D_ASSERT(list_empty(&mdev->go_diskless.list));
1951 drbd_set_defaults(mdev);
1955 static void drbd_destroy_mempools(void)
1959 while (drbd_pp_pool) {
1960 page = drbd_pp_pool;
1961 drbd_pp_pool = (struct page *)page_private(page);
1966 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
1968 if (drbd_md_io_bio_set)
1969 bioset_free(drbd_md_io_bio_set);
1970 if (drbd_md_io_page_pool)
1971 mempool_destroy(drbd_md_io_page_pool);
1972 if (drbd_ee_mempool)
1973 mempool_destroy(drbd_ee_mempool);
1974 if (drbd_request_mempool)
1975 mempool_destroy(drbd_request_mempool);
1977 kmem_cache_destroy(drbd_ee_cache);
1978 if (drbd_request_cache)
1979 kmem_cache_destroy(drbd_request_cache);
1980 if (drbd_bm_ext_cache)
1981 kmem_cache_destroy(drbd_bm_ext_cache);
1982 if (drbd_al_ext_cache)
1983 kmem_cache_destroy(drbd_al_ext_cache);
1985 drbd_md_io_bio_set = NULL;
1986 drbd_md_io_page_pool = NULL;
1987 drbd_ee_mempool = NULL;
1988 drbd_request_mempool = NULL;
1989 drbd_ee_cache = NULL;
1990 drbd_request_cache = NULL;
1991 drbd_bm_ext_cache = NULL;
1992 drbd_al_ext_cache = NULL;
1997 static int drbd_create_mempools(void)
2000 const int number = (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count;
2003 /* prepare our caches and mempools */
2004 drbd_request_mempool = NULL;
2005 drbd_ee_cache = NULL;
2006 drbd_request_cache = NULL;
2007 drbd_bm_ext_cache = NULL;
2008 drbd_al_ext_cache = NULL;
2009 drbd_pp_pool = NULL;
2010 drbd_md_io_page_pool = NULL;
2011 drbd_md_io_bio_set = NULL;
2014 drbd_request_cache = kmem_cache_create(
2015 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
2016 if (drbd_request_cache == NULL)
2019 drbd_ee_cache = kmem_cache_create(
2020 "drbd_ee", sizeof(struct drbd_peer_request), 0, 0, NULL);
2021 if (drbd_ee_cache == NULL)
2024 drbd_bm_ext_cache = kmem_cache_create(
2025 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
2026 if (drbd_bm_ext_cache == NULL)
2029 drbd_al_ext_cache = kmem_cache_create(
2030 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
2031 if (drbd_al_ext_cache == NULL)
2035 drbd_md_io_bio_set = bioset_create(DRBD_MIN_POOL_PAGES, 0);
2036 if (drbd_md_io_bio_set == NULL)
2039 drbd_md_io_page_pool = mempool_create_page_pool(DRBD_MIN_POOL_PAGES, 0);
2040 if (drbd_md_io_page_pool == NULL)
2043 drbd_request_mempool = mempool_create(number,
2044 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
2045 if (drbd_request_mempool == NULL)
2048 drbd_ee_mempool = mempool_create(number,
2049 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2050 if (drbd_ee_mempool == NULL)
2053 /* drbd's page pool */
2054 spin_lock_init(&drbd_pp_lock);
2056 for (i = 0; i < number; i++) {
2057 page = alloc_page(GFP_HIGHUSER);
2060 set_page_private(page, (unsigned long)drbd_pp_pool);
2061 drbd_pp_pool = page;
2063 drbd_pp_vacant = number;
2068 drbd_destroy_mempools(); /* in case we allocated some */
2072 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
2075 /* just so we have it. you never know what interesting things we
2076 * might want to do here some day...
2082 static struct notifier_block drbd_notifier = {
2083 .notifier_call = drbd_notify_sys,
2086 static void drbd_release_ee_lists(struct drbd_conf *mdev)
2090 rr = drbd_release_ee(mdev, &mdev->active_ee);
2092 dev_err(DEV, "%d EEs in active list found!\n", rr);
2094 rr = drbd_release_ee(mdev, &mdev->sync_ee);
2096 dev_err(DEV, "%d EEs in sync list found!\n", rr);
2098 rr = drbd_release_ee(mdev, &mdev->read_ee);
2100 dev_err(DEV, "%d EEs in read list found!\n", rr);
2102 rr = drbd_release_ee(mdev, &mdev->done_ee);
2104 dev_err(DEV, "%d EEs in done list found!\n", rr);
2106 rr = drbd_release_ee(mdev, &mdev->net_ee);
2108 dev_err(DEV, "%d EEs in net list found!\n", rr);
2111 /* caution. no locking. */
2112 void drbd_delete_device(unsigned int minor)
2114 struct drbd_conf *mdev = minor_to_mdev(minor);
2119 idr_remove(&mdev->tconn->volumes, mdev->vnr);
2120 idr_remove(&minors, minor);
2123 /* paranoia asserts */
2124 D_ASSERT(mdev->open_cnt == 0);
2125 D_ASSERT(list_empty(&mdev->tconn->data.work.q));
2126 /* end paranoia asserts */
2128 del_gendisk(mdev->vdisk);
2130 /* cleanup stuff that may have been allocated during
2131 * device (re-)configuration or state changes */
2133 if (mdev->this_bdev)
2134 bdput(mdev->this_bdev);
2136 drbd_free_resources(mdev);
2138 drbd_release_ee_lists(mdev);
2140 lc_destroy(mdev->act_log);
2141 lc_destroy(mdev->resync);
2143 kfree(mdev->p_uuid);
2144 /* mdev->p_uuid = NULL; */
2146 /* cleanup the rest that has been
2147 * allocated from drbd_new_device
2148 * and actually free the mdev itself */
2149 drbd_free_mdev(mdev);
2152 static void drbd_cleanup(void)
2155 struct drbd_conf *mdev;
2157 unregister_reboot_notifier(&drbd_notifier);
2159 /* first remove proc,
2160 * drbdsetup uses it's presence to detect
2161 * whether DRBD is loaded.
2162 * If we would get stuck in proc removal,
2163 * but have netlink already deregistered,
2164 * some drbdsetup commands may wait forever
2168 remove_proc_entry("drbd", NULL);
2170 drbd_genl_unregister();
2172 idr_for_each_entry(&minors, mdev, i)
2173 drbd_delete_device(i);
2174 drbd_destroy_mempools();
2175 unregister_blkdev(DRBD_MAJOR, "drbd");
2177 idr_destroy(&minors);
2179 printk(KERN_INFO "drbd: module cleanup done.\n");
2183 * drbd_congested() - Callback for pdflush
2184 * @congested_data: User data
2185 * @bdi_bits: Bits pdflush is currently interested in
2187 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
2189 static int drbd_congested(void *congested_data, int bdi_bits)
2191 struct drbd_conf *mdev = congested_data;
2192 struct request_queue *q;
2196 if (!may_inc_ap_bio(mdev)) {
2197 /* DRBD has frozen IO */
2203 if (get_ldev(mdev)) {
2204 q = bdev_get_queue(mdev->ldev->backing_bdev);
2205 r = bdi_congested(&q->backing_dev_info, bdi_bits);
2211 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->tconn->flags)) {
2212 r |= (1 << BDI_async_congested);
2213 reason = reason == 'b' ? 'a' : 'n';
2217 mdev->congestion_reason = reason;
2221 static void drbd_init_workqueue(struct drbd_work_queue* wq)
2223 sema_init(&wq->s, 0);
2224 spin_lock_init(&wq->q_lock);
2225 INIT_LIST_HEAD(&wq->q);
2228 struct drbd_tconn *conn_by_name(const char *name)
2230 struct drbd_tconn *tconn;
2232 if (!name || !name[0])
2235 mutex_lock(&drbd_cfg_mutex);
2236 list_for_each_entry(tconn, &drbd_tconns, all_tconn) {
2237 if (!strcmp(tconn->name, name))
2242 mutex_unlock(&drbd_cfg_mutex);
2246 struct drbd_tconn *drbd_new_tconn(const char *name)
2248 struct drbd_tconn *tconn;
2250 tconn = kzalloc(sizeof(struct drbd_tconn), GFP_KERNEL);
2254 tconn->name = kstrdup(name, GFP_KERNEL);
2258 if (!zalloc_cpumask_var(&tconn->cpu_mask, GFP_KERNEL))
2261 if (!tl_init(tconn))
2264 tconn->cstate = C_STANDALONE;
2265 mutex_init(&tconn->cstate_mutex);
2266 spin_lock_init(&tconn->req_lock);
2267 atomic_set(&tconn->net_cnt, 0);
2268 init_waitqueue_head(&tconn->net_cnt_wait);
2269 init_waitqueue_head(&tconn->ping_wait);
2270 idr_init(&tconn->volumes);
2272 drbd_init_workqueue(&tconn->data.work);
2273 mutex_init(&tconn->data.mutex);
2275 drbd_init_workqueue(&tconn->meta.work);
2276 mutex_init(&tconn->meta.mutex);
2278 drbd_thread_init(tconn, &tconn->receiver, drbdd_init, "receiver");
2279 drbd_thread_init(tconn, &tconn->worker, drbd_worker, "worker");
2280 drbd_thread_init(tconn, &tconn->asender, drbd_asender, "asender");
2282 tconn->res_opts = (struct res_opts) {
2283 {}, 0, /* cpu_mask */
2284 DRBD_ON_NO_DATA_DEF, /* on_no_data */
2287 mutex_lock(&drbd_cfg_mutex);
2288 list_add_tail(&tconn->all_tconn, &drbd_tconns);
2289 mutex_unlock(&drbd_cfg_mutex);
2295 free_cpumask_var(tconn->cpu_mask);
2302 void drbd_free_tconn(struct drbd_tconn *tconn)
2304 list_del(&tconn->all_tconn);
2305 idr_destroy(&tconn->volumes);
2307 free_cpumask_var(tconn->cpu_mask);
2309 kfree(tconn->int_dig_out);
2310 kfree(tconn->int_dig_in);
2311 kfree(tconn->int_dig_vv);
2315 enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor, int vnr)
2317 struct drbd_conf *mdev;
2318 struct gendisk *disk;
2319 struct request_queue *q;
2321 int minor_got = minor;
2322 enum drbd_ret_code err = ERR_NOMEM;
2324 mdev = minor_to_mdev(minor);
2326 return ERR_MINOR_EXISTS;
2328 /* GFP_KERNEL, we are outside of all write-out paths */
2329 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
2333 mdev->tconn = tconn;
2334 mdev->minor = minor;
2337 drbd_init_set_defaults(mdev);
2339 q = blk_alloc_queue(GFP_KERNEL);
2343 q->queuedata = mdev;
2345 disk = alloc_disk(1);
2350 set_disk_ro(disk, true);
2353 disk->major = DRBD_MAJOR;
2354 disk->first_minor = minor;
2355 disk->fops = &drbd_ops;
2356 sprintf(disk->disk_name, "drbd%d", minor);
2357 disk->private_data = mdev;
2359 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
2360 /* we have no partitions. we contain only ourselves. */
2361 mdev->this_bdev->bd_contains = mdev->this_bdev;
2363 q->backing_dev_info.congested_fn = drbd_congested;
2364 q->backing_dev_info.congested_data = mdev;
2366 blk_queue_make_request(q, drbd_make_request);
2367 /* Setting the max_hw_sectors to an odd value of 8kibyte here
2368 This triggers a max_bio_size message upon first attach or connect */
2369 blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8);
2370 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
2371 blk_queue_merge_bvec(q, drbd_merge_bvec);
2372 q->queue_lock = &mdev->tconn->req_lock; /* needed since we use */
2374 mdev->md_io_page = alloc_page(GFP_KERNEL);
2375 if (!mdev->md_io_page)
2376 goto out_no_io_page;
2378 if (drbd_bm_init(mdev))
2380 mdev->read_requests = RB_ROOT;
2381 mdev->write_requests = RB_ROOT;
2383 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
2384 if (!mdev->current_epoch)
2387 INIT_LIST_HEAD(&mdev->current_epoch->list);
2390 if (!idr_pre_get(&minors, GFP_KERNEL))
2391 goto out_no_minor_idr;
2392 if (idr_get_new_above(&minors, mdev, minor, &minor_got))
2393 goto out_no_minor_idr;
2394 if (minor_got != minor) {
2395 err = ERR_MINOR_EXISTS;
2396 drbd_msg_put_info("requested minor exists already");
2397 goto out_idr_remove_minor;
2400 if (!idr_pre_get(&tconn->volumes, GFP_KERNEL))
2401 goto out_idr_remove_minor;
2402 if (idr_get_new_above(&tconn->volumes, mdev, vnr, &vnr_got))
2403 goto out_idr_remove_minor;
2404 if (vnr_got != vnr) {
2405 err = ERR_INVALID_REQUEST;
2406 drbd_msg_put_info("requested volume exists already");
2407 goto out_idr_remove_vol;
2411 /* inherit the connection state */
2412 mdev->state.conn = tconn->cstate;
2413 if (mdev->state.conn == C_WF_REPORT_PARAMS)
2414 drbd_connected(vnr, mdev, tconn);
2419 idr_remove(&tconn->volumes, vnr_got);
2420 out_idr_remove_minor:
2421 idr_remove(&minors, minor_got);
2424 kfree(mdev->current_epoch);
2426 drbd_bm_cleanup(mdev);
2428 __free_page(mdev->md_io_page);
2432 blk_cleanup_queue(q);
2438 /* counterpart of drbd_new_device.
2439 * last part of drbd_delete_device. */
2440 void drbd_free_mdev(struct drbd_conf *mdev)
2442 kfree(mdev->current_epoch);
2443 if (mdev->bitmap) /* should no longer be there. */
2444 drbd_bm_cleanup(mdev);
2445 __free_page(mdev->md_io_page);
2446 put_disk(mdev->vdisk);
2447 blk_cleanup_queue(mdev->rq_queue);
2452 int __init drbd_init(void)
2456 BUILD_BUG_ON(sizeof(struct p_header80) != sizeof(struct p_header95));
2457 BUILD_BUG_ON(sizeof(struct p_handshake) != 80);
2459 if (minor_count < DRBD_MINOR_COUNT_MIN || minor_count > DRBD_MINOR_COUNT_MAX) {
2461 "drbd: invalid minor_count (%d)\n", minor_count);
2469 err = register_blkdev(DRBD_MAJOR, "drbd");
2472 "drbd: unable to register block device major %d\n",
2477 err = drbd_genl_register();
2479 printk(KERN_ERR "drbd: unable to register generic netlink family\n");
2484 register_reboot_notifier(&drbd_notifier);
2487 * allocate all necessary structs
2491 init_waitqueue_head(&drbd_pp_wait);
2493 drbd_proc = NULL; /* play safe for drbd_cleanup */
2496 err = drbd_create_mempools();
2500 drbd_proc = proc_create_data("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops, NULL);
2502 printk(KERN_ERR "drbd: unable to register proc file\n");
2506 rwlock_init(&global_state_lock);
2507 INIT_LIST_HEAD(&drbd_tconns);
2509 printk(KERN_INFO "drbd: initialized. "
2510 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
2511 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
2512 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
2513 printk(KERN_INFO "drbd: registered as block device major %d\n",
2516 return 0; /* Success! */
2521 /* currently always the case */
2522 printk(KERN_ERR "drbd: ran out of memory\n");
2524 printk(KERN_ERR "drbd: initialization failure\n");
2528 void drbd_free_bc(struct drbd_backing_dev *ldev)
2533 blkdev_put(ldev->backing_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
2534 blkdev_put(ldev->md_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
2539 void drbd_free_sock(struct drbd_tconn *tconn)
2541 if (tconn->data.socket) {
2542 mutex_lock(&tconn->data.mutex);
2543 kernel_sock_shutdown(tconn->data.socket, SHUT_RDWR);
2544 sock_release(tconn->data.socket);
2545 tconn->data.socket = NULL;
2546 mutex_unlock(&tconn->data.mutex);
2548 if (tconn->meta.socket) {
2549 mutex_lock(&tconn->meta.mutex);
2550 kernel_sock_shutdown(tconn->meta.socket, SHUT_RDWR);
2551 sock_release(tconn->meta.socket);
2552 tconn->meta.socket = NULL;
2553 mutex_unlock(&tconn->meta.mutex);
2558 void drbd_free_resources(struct drbd_conf *mdev)
2560 crypto_free_hash(mdev->tconn->csums_tfm);
2561 mdev->tconn->csums_tfm = NULL;
2562 crypto_free_hash(mdev->tconn->verify_tfm);
2563 mdev->tconn->verify_tfm = NULL;
2564 crypto_free_hash(mdev->tconn->cram_hmac_tfm);
2565 mdev->tconn->cram_hmac_tfm = NULL;
2566 crypto_free_hash(mdev->tconn->integrity_w_tfm);
2567 mdev->tconn->integrity_w_tfm = NULL;
2568 crypto_free_hash(mdev->tconn->integrity_r_tfm);
2569 mdev->tconn->integrity_r_tfm = NULL;
2571 drbd_free_sock(mdev->tconn);
2574 drbd_free_bc(mdev->ldev);
2575 mdev->ldev = NULL;);
2578 /* meta data management */
2580 struct meta_data_on_disk {
2581 u64 la_size; /* last agreed size. */
2582 u64 uuid[UI_SIZE]; /* UUIDs. */
2585 u32 flags; /* MDF */
2588 u32 al_offset; /* offset to this block */
2589 u32 al_nr_extents; /* important for restoring the AL */
2590 /* `-- act_log->nr_elements <-- ldev->dc.al_extents */
2591 u32 bm_offset; /* offset to the bitmap, from here */
2592 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
2593 u32 la_peer_max_bio_size; /* last peer max_bio_size */
2594 u32 reserved_u32[3];
2599 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
2600 * @mdev: DRBD device.
2602 void drbd_md_sync(struct drbd_conf *mdev)
2604 struct meta_data_on_disk *buffer;
2608 del_timer(&mdev->md_sync_timer);
2609 /* timer may be rearmed by drbd_md_mark_dirty() now. */
2610 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
2613 /* We use here D_FAILED and not D_ATTACHING because we try to write
2614 * metadata even if we detach due to a disk failure! */
2615 if (!get_ldev_if_state(mdev, D_FAILED))
2618 mutex_lock(&mdev->md_io_mutex);
2619 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
2620 memset(buffer, 0, 512);
2622 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
2623 for (i = UI_CURRENT; i < UI_SIZE; i++)
2624 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
2625 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
2626 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
2628 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
2629 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
2630 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
2631 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
2632 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
2634 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
2635 buffer->la_peer_max_bio_size = cpu_to_be32(mdev->peer_max_bio_size);
2637 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
2638 sector = mdev->ldev->md.md_offset;
2640 if (!drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
2641 /* this was a try anyways ... */
2642 dev_err(DEV, "meta data update failed!\n");
2643 drbd_chk_io_error(mdev, 1, true);
2646 /* Update mdev->ldev->md.la_size_sect,
2647 * since we updated it on metadata. */
2648 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
2650 mutex_unlock(&mdev->md_io_mutex);
2655 * drbd_md_read() - Reads in the meta data super block
2656 * @mdev: DRBD device.
2657 * @bdev: Device from which the meta data should be read in.
2659 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_code in case
2660 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
2662 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
2664 struct meta_data_on_disk *buffer;
2665 int i, rv = NO_ERROR;
2667 if (!get_ldev_if_state(mdev, D_ATTACHING))
2668 return ERR_IO_MD_DISK;
2670 mutex_lock(&mdev->md_io_mutex);
2671 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
2673 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
2674 /* NOTE: can't do normal error processing here as this is
2675 called BEFORE disk is attached */
2676 dev_err(DEV, "Error while reading metadata.\n");
2677 rv = ERR_IO_MD_DISK;
2681 if (buffer->magic != cpu_to_be32(DRBD_MD_MAGIC)) {
2682 dev_err(DEV, "Error while reading metadata, magic not found.\n");
2683 rv = ERR_MD_INVALID;
2686 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
2687 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
2688 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
2689 rv = ERR_MD_INVALID;
2692 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
2693 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
2694 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
2695 rv = ERR_MD_INVALID;
2698 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
2699 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
2700 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
2701 rv = ERR_MD_INVALID;
2705 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
2706 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
2707 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
2708 rv = ERR_MD_INVALID;
2712 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
2713 for (i = UI_CURRENT; i < UI_SIZE; i++)
2714 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
2715 bdev->md.flags = be32_to_cpu(buffer->flags);
2716 bdev->dc.al_extents = be32_to_cpu(buffer->al_nr_extents);
2717 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
2719 spin_lock_irq(&mdev->tconn->req_lock);
2720 if (mdev->state.conn < C_CONNECTED) {
2722 peer = be32_to_cpu(buffer->la_peer_max_bio_size);
2723 peer = max_t(int, peer, DRBD_MAX_BIO_SIZE_SAFE);
2724 mdev->peer_max_bio_size = peer;
2726 spin_unlock_irq(&mdev->tconn->req_lock);
2728 if (bdev->dc.al_extents < 7)
2729 bdev->dc.al_extents = 127;
2732 mutex_unlock(&mdev->md_io_mutex);
2739 * drbd_md_mark_dirty() - Mark meta data super block as dirty
2740 * @mdev: DRBD device.
2742 * Call this function if you change anything that should be written to
2743 * the meta-data super block. This function sets MD_DIRTY, and starts a
2744 * timer that ensures that within five seconds you have to call drbd_md_sync().
2747 void drbd_md_mark_dirty_(struct drbd_conf *mdev, unsigned int line, const char *func)
2749 if (!test_and_set_bit(MD_DIRTY, &mdev->flags)) {
2750 mod_timer(&mdev->md_sync_timer, jiffies + HZ);
2751 mdev->last_md_mark_dirty.line = line;
2752 mdev->last_md_mark_dirty.func = func;
2756 void drbd_md_mark_dirty(struct drbd_conf *mdev)
2758 if (!test_and_set_bit(MD_DIRTY, &mdev->flags))
2759 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
2763 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
2767 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
2768 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
2771 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
2773 if (idx == UI_CURRENT) {
2774 if (mdev->state.role == R_PRIMARY)
2779 drbd_set_ed_uuid(mdev, val);
2782 mdev->ldev->md.uuid[idx] = val;
2783 drbd_md_mark_dirty(mdev);
2787 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
2789 if (mdev->ldev->md.uuid[idx]) {
2790 drbd_uuid_move_history(mdev);
2791 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
2793 _drbd_uuid_set(mdev, idx, val);
2797 * drbd_uuid_new_current() - Creates a new current UUID
2798 * @mdev: DRBD device.
2800 * Creates a new current UUID, and rotates the old current UUID into
2801 * the bitmap slot. Causes an incremental resync upon next connect.
2803 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
2806 unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];
2809 dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
2811 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
2813 get_random_bytes(&val, sizeof(u64));
2814 _drbd_uuid_set(mdev, UI_CURRENT, val);
2815 drbd_print_uuids(mdev, "new current UUID");
2816 /* get it to stable storage _now_ */
2820 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
2822 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
2826 drbd_uuid_move_history(mdev);
2827 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
2828 mdev->ldev->md.uuid[UI_BITMAP] = 0;
2830 unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];
2832 dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
2834 mdev->ldev->md.uuid[UI_BITMAP] = val & ~((u64)1);
2836 drbd_md_mark_dirty(mdev);
2840 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
2841 * @mdev: DRBD device.
2843 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
2845 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
2849 if (get_ldev_if_state(mdev, D_ATTACHING)) {
2850 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
2852 drbd_bm_set_all(mdev);
2854 rv = drbd_bm_write(mdev);
2857 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2868 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
2869 * @mdev: DRBD device.
2871 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
2873 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
2877 drbd_resume_al(mdev);
2878 if (get_ldev_if_state(mdev, D_ATTACHING)) {
2879 drbd_bm_clear_all(mdev);
2880 rv = drbd_bm_write(mdev);
2887 static int w_bitmap_io(struct drbd_work *w, int unused)
2889 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
2890 struct drbd_conf *mdev = w->mdev;
2893 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
2895 if (get_ldev(mdev)) {
2896 drbd_bm_lock(mdev, work->why, work->flags);
2897 rv = work->io_fn(mdev);
2898 drbd_bm_unlock(mdev);
2902 clear_bit_unlock(BITMAP_IO, &mdev->flags);
2903 wake_up(&mdev->misc_wait);
2906 work->done(mdev, rv);
2908 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
2915 void drbd_ldev_destroy(struct drbd_conf *mdev)
2917 lc_destroy(mdev->resync);
2918 mdev->resync = NULL;
2919 lc_destroy(mdev->act_log);
2920 mdev->act_log = NULL;
2922 drbd_free_bc(mdev->ldev);
2923 mdev->ldev = NULL;);
2925 clear_bit(GO_DISKLESS, &mdev->flags);
2928 static int w_go_diskless(struct drbd_work *w, int unused)
2930 struct drbd_conf *mdev = w->mdev;
2932 D_ASSERT(mdev->state.disk == D_FAILED);
2933 /* we cannot assert local_cnt == 0 here, as get_ldev_if_state will
2934 * inc/dec it frequently. Once we are D_DISKLESS, no one will touch
2935 * the protected members anymore, though, so once put_ldev reaches zero
2936 * again, it will be safe to free them. */
2937 drbd_force_state(mdev, NS(disk, D_DISKLESS));
2941 void drbd_go_diskless(struct drbd_conf *mdev)
2943 D_ASSERT(mdev->state.disk == D_FAILED);
2944 if (!test_and_set_bit(GO_DISKLESS, &mdev->flags))
2945 drbd_queue_work(&mdev->tconn->data.work, &mdev->go_diskless);
2949 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
2950 * @mdev: DRBD device.
2951 * @io_fn: IO callback to be called when bitmap IO is possible
2952 * @done: callback to be called after the bitmap IO was performed
2953 * @why: Descriptive text of the reason for doing the IO
2955 * While IO on the bitmap happens we freeze application IO thus we ensure
2956 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
2957 * called from worker context. It MUST NOT be used while a previous such
2958 * work is still pending!
2960 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
2961 int (*io_fn)(struct drbd_conf *),
2962 void (*done)(struct drbd_conf *, int),
2963 char *why, enum bm_flag flags)
2965 D_ASSERT(current == mdev->tconn->worker.task);
2967 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
2968 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
2969 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
2970 if (mdev->bm_io_work.why)
2971 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
2972 why, mdev->bm_io_work.why);
2974 mdev->bm_io_work.io_fn = io_fn;
2975 mdev->bm_io_work.done = done;
2976 mdev->bm_io_work.why = why;
2977 mdev->bm_io_work.flags = flags;
2979 spin_lock_irq(&mdev->tconn->req_lock);
2980 set_bit(BITMAP_IO, &mdev->flags);
2981 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
2982 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
2983 drbd_queue_work(&mdev->tconn->data.work, &mdev->bm_io_work.w);
2985 spin_unlock_irq(&mdev->tconn->req_lock);
2989 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
2990 * @mdev: DRBD device.
2991 * @io_fn: IO callback to be called when bitmap IO is possible
2992 * @why: Descriptive text of the reason for doing the IO
2994 * freezes application IO while that the actual IO operations runs. This
2995 * functions MAY NOT be called from worker context.
2997 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *),
2998 char *why, enum bm_flag flags)
3002 D_ASSERT(current != mdev->tconn->worker.task);
3004 if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
3005 drbd_suspend_io(mdev);
3007 drbd_bm_lock(mdev, why, flags);
3009 drbd_bm_unlock(mdev);
3011 if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
3012 drbd_resume_io(mdev);
3017 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3019 if ((mdev->ldev->md.flags & flag) != flag) {
3020 drbd_md_mark_dirty(mdev);
3021 mdev->ldev->md.flags |= flag;
3025 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3027 if ((mdev->ldev->md.flags & flag) != 0) {
3028 drbd_md_mark_dirty(mdev);
3029 mdev->ldev->md.flags &= ~flag;
3032 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
3034 return (bdev->md.flags & flag) != 0;
3037 static void md_sync_timer_fn(unsigned long data)
3039 struct drbd_conf *mdev = (struct drbd_conf *) data;
3041 drbd_queue_work_front(&mdev->tconn->data.work, &mdev->md_sync_work);
3044 static int w_md_sync(struct drbd_work *w, int unused)
3046 struct drbd_conf *mdev = w->mdev;
3048 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3050 dev_warn(DEV, "last md_mark_dirty: %s:%u\n",
3051 mdev->last_md_mark_dirty.func, mdev->last_md_mark_dirty.line);
3057 const char *cmdname(enum drbd_packet cmd)
3059 /* THINK may need to become several global tables
3060 * when we want to support more than
3061 * one PRO_VERSION */
3062 static const char *cmdnames[] = {
3064 [P_DATA_REPLY] = "DataReply",
3065 [P_RS_DATA_REPLY] = "RSDataReply",
3066 [P_BARRIER] = "Barrier",
3067 [P_BITMAP] = "ReportBitMap",
3068 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget",
3069 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource",
3070 [P_UNPLUG_REMOTE] = "UnplugRemote",
3071 [P_DATA_REQUEST] = "DataRequest",
3072 [P_RS_DATA_REQUEST] = "RSDataRequest",
3073 [P_SYNC_PARAM] = "SyncParam",
3074 [P_SYNC_PARAM89] = "SyncParam89",
3075 [P_PROTOCOL] = "ReportProtocol",
3076 [P_UUIDS] = "ReportUUIDs",
3077 [P_SIZES] = "ReportSizes",
3078 [P_STATE] = "ReportState",
3079 [P_SYNC_UUID] = "ReportSyncUUID",
3080 [P_AUTH_CHALLENGE] = "AuthChallenge",
3081 [P_AUTH_RESPONSE] = "AuthResponse",
3083 [P_PING_ACK] = "PingAck",
3084 [P_RECV_ACK] = "RecvAck",
3085 [P_WRITE_ACK] = "WriteAck",
3086 [P_RS_WRITE_ACK] = "RSWriteAck",
3087 [P_DISCARD_WRITE] = "DiscardWrite",
3088 [P_NEG_ACK] = "NegAck",
3089 [P_NEG_DREPLY] = "NegDReply",
3090 [P_NEG_RS_DREPLY] = "NegRSDReply",
3091 [P_BARRIER_ACK] = "BarrierAck",
3092 [P_STATE_CHG_REQ] = "StateChgRequest",
3093 [P_STATE_CHG_REPLY] = "StateChgReply",
3094 [P_OV_REQUEST] = "OVRequest",
3095 [P_OV_REPLY] = "OVReply",
3096 [P_OV_RESULT] = "OVResult",
3097 [P_CSUM_RS_REQUEST] = "CsumRSRequest",
3098 [P_RS_IS_IN_SYNC] = "CsumRSIsInSync",
3099 [P_COMPRESSED_BITMAP] = "CBitmap",
3100 [P_DELAY_PROBE] = "DelayProbe",
3101 [P_OUT_OF_SYNC] = "OutOfSync",
3102 [P_RETRY_WRITE] = "RetryWrite",
3105 if (cmd == P_HAND_SHAKE_M)
3106 return "HandShakeM";
3107 if (cmd == P_HAND_SHAKE_S)
3108 return "HandShakeS";
3109 if (cmd == P_HAND_SHAKE)
3111 if (cmd >= ARRAY_SIZE(cmdnames))
3113 return cmdnames[cmd];
3117 * drbd_wait_misc - wait for a request to make progress
3118 * @mdev: device associated with the request
3119 * @i: the struct drbd_interval embedded in struct drbd_request or
3120 * struct drbd_peer_request
3122 int drbd_wait_misc(struct drbd_conf *mdev, struct drbd_interval *i)
3124 struct net_conf *net_conf = mdev->tconn->net_conf;
3130 timeout = MAX_SCHEDULE_TIMEOUT;
3131 if (net_conf->ko_count)
3132 timeout = net_conf->timeout * HZ / 10 * net_conf->ko_count;
3134 /* Indicate to wake up mdev->misc_wait on progress. */
3136 prepare_to_wait(&mdev->misc_wait, &wait, TASK_INTERRUPTIBLE);
3137 spin_unlock_irq(&mdev->tconn->req_lock);
3138 timeout = schedule_timeout(timeout);
3139 finish_wait(&mdev->misc_wait, &wait);
3140 spin_lock_irq(&mdev->tconn->req_lock);
3141 if (!timeout || mdev->state.conn < C_CONNECTED)
3143 if (signal_pending(current))
3144 return -ERESTARTSYS;
3148 #ifdef CONFIG_DRBD_FAULT_INJECTION
3149 /* Fault insertion support including random number generator shamelessly
3150 * stolen from kernel/rcutorture.c */
3151 struct fault_random_state {
3152 unsigned long state;
3153 unsigned long count;
3156 #define FAULT_RANDOM_MULT 39916801 /* prime */
3157 #define FAULT_RANDOM_ADD 479001701 /* prime */
3158 #define FAULT_RANDOM_REFRESH 10000
3161 * Crude but fast random-number generator. Uses a linear congruential
3162 * generator, with occasional help from get_random_bytes().
3164 static unsigned long
3165 _drbd_fault_random(struct fault_random_state *rsp)
3169 if (!rsp->count--) {
3170 get_random_bytes(&refresh, sizeof(refresh));
3171 rsp->state += refresh;
3172 rsp->count = FAULT_RANDOM_REFRESH;
3174 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
3175 return swahw32(rsp->state);
3179 _drbd_fault_str(unsigned int type) {
3180 static char *_faults[] = {
3181 [DRBD_FAULT_MD_WR] = "Meta-data write",
3182 [DRBD_FAULT_MD_RD] = "Meta-data read",
3183 [DRBD_FAULT_RS_WR] = "Resync write",
3184 [DRBD_FAULT_RS_RD] = "Resync read",
3185 [DRBD_FAULT_DT_WR] = "Data write",
3186 [DRBD_FAULT_DT_RD] = "Data read",
3187 [DRBD_FAULT_DT_RA] = "Data read ahead",
3188 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
3189 [DRBD_FAULT_AL_EE] = "EE allocation",
3190 [DRBD_FAULT_RECEIVE] = "receive data corruption",
3193 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
3197 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
3199 static struct fault_random_state rrs = {0, 0};
3201 unsigned int ret = (
3203 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
3204 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
3209 if (__ratelimit(&drbd_ratelimit_state))
3210 dev_warn(DEV, "***Simulating %s failure\n",
3211 _drbd_fault_str(type));
3218 const char *drbd_buildtag(void)
3220 /* DRBD built from external sources has here a reference to the
3221 git hash of the source code. */
3223 static char buildtag[38] = "\0uilt-in";
3225 if (buildtag[0] == 0) {
3226 #ifdef CONFIG_MODULES
3227 if (THIS_MODULE != NULL)
3228 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
3237 module_init(drbd_init)
3238 module_exit(drbd_cleanup)
3240 EXPORT_SYMBOL(drbd_conn_str);
3241 EXPORT_SYMBOL(drbd_role_str);
3242 EXPORT_SYMBOL(drbd_disk_str);
3243 EXPORT_SYMBOL(drbd_set_st_err_str);