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) {
1476 if (_drbd_no_send_page(mdev, bvec->bv_page,
1477 bvec->bv_offset, bvec->bv_len,
1478 i == bio->bi_vcnt -1 ? 0 : MSG_MORE))
1484 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
1486 struct bio_vec *bvec;
1488 /* hint all but last page with MSG_MORE */
1489 __bio_for_each_segment(bvec, bio, i, 0) {
1490 if (_drbd_send_page(mdev, bvec->bv_page,
1491 bvec->bv_offset, bvec->bv_len,
1492 i == bio->bi_vcnt -1 ? 0 : MSG_MORE))
1498 static int _drbd_send_zc_ee(struct drbd_conf *mdev,
1499 struct drbd_peer_request *peer_req)
1501 struct page *page = peer_req->pages;
1502 unsigned len = peer_req->i.size;
1505 /* hint all but last page with MSG_MORE */
1506 page_chain_for_each(page) {
1507 unsigned l = min_t(unsigned, len, PAGE_SIZE);
1509 err = _drbd_send_page(mdev, page, 0, l,
1510 page_chain_next(page) ? MSG_MORE : 0);
1518 static u32 bio_flags_to_wire(struct drbd_conf *mdev, unsigned long bi_rw)
1520 if (mdev->tconn->agreed_pro_version >= 95)
1521 return (bi_rw & REQ_SYNC ? DP_RW_SYNC : 0) |
1522 (bi_rw & REQ_FUA ? DP_FUA : 0) |
1523 (bi_rw & REQ_FLUSH ? DP_FLUSH : 0) |
1524 (bi_rw & REQ_DISCARD ? DP_DISCARD : 0);
1526 return bi_rw & REQ_SYNC ? DP_RW_SYNC : 0;
1529 /* Used to send write requests
1530 * R_PRIMARY -> Peer (P_DATA)
1532 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
1536 unsigned int dp_flags = 0;
1540 if (drbd_get_data_sock(mdev->tconn))
1543 dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_w_tfm) ?
1544 crypto_hash_digestsize(mdev->tconn->integrity_w_tfm) : 0;
1546 prepare_header(mdev, &p.head, P_DATA, sizeof(p) - sizeof(struct p_header) + dgs + req->i.size);
1547 p.sector = cpu_to_be64(req->i.sector);
1548 p.block_id = (unsigned long)req;
1549 p.seq_num = cpu_to_be32(req->seq_num = atomic_inc_return(&mdev->packet_seq));
1551 dp_flags = bio_flags_to_wire(mdev, req->master_bio->bi_rw);
1553 if (mdev->state.conn >= C_SYNC_SOURCE &&
1554 mdev->state.conn <= C_PAUSED_SYNC_T)
1555 dp_flags |= DP_MAY_SET_IN_SYNC;
1557 p.dp_flags = cpu_to_be32(dp_flags);
1558 set_bit(UNPLUG_REMOTE, &mdev->flags);
1560 drbd_send(mdev->tconn, mdev->tconn->data.socket, &p, sizeof(p), dgs ? MSG_MORE : 0));
1562 dgb = mdev->tconn->int_dig_out;
1563 drbd_csum_bio(mdev, mdev->tconn->integrity_w_tfm, req->master_bio, dgb);
1564 ok = dgs == drbd_send(mdev->tconn, mdev->tconn->data.socket, dgb, dgs, 0);
1567 /* For protocol A, we have to memcpy the payload into
1568 * socket buffers, as we may complete right away
1569 * as soon as we handed it over to tcp, at which point the data
1570 * pages may become invalid.
1572 * For data-integrity enabled, we copy it as well, so we can be
1573 * sure that even if the bio pages may still be modified, it
1574 * won't change the data on the wire, thus if the digest checks
1575 * out ok after sending on this side, but does not fit on the
1576 * receiving side, we sure have detected corruption elsewhere.
1578 if (mdev->tconn->net_conf->wire_protocol == DRBD_PROT_A || dgs)
1579 ok = _drbd_send_bio(mdev, req->master_bio);
1581 ok = _drbd_send_zc_bio(mdev, req->master_bio);
1583 /* double check digest, sometimes buffers have been modified in flight. */
1584 if (dgs > 0 && dgs <= 64) {
1585 /* 64 byte, 512 bit, is the largest digest size
1586 * currently supported in kernel crypto. */
1587 unsigned char digest[64];
1588 drbd_csum_bio(mdev, mdev->tconn->integrity_w_tfm, req->master_bio, digest);
1589 if (memcmp(mdev->tconn->int_dig_out, digest, dgs)) {
1591 "Digest mismatch, buffer modified by upper layers during write: %llus +%u\n",
1592 (unsigned long long)req->i.sector, req->i.size);
1594 } /* else if (dgs > 64) {
1595 ... Be noisy about digest too large ...
1599 drbd_put_data_sock(mdev->tconn);
1604 /* answer packet, used to send data back for read requests:
1605 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
1606 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
1608 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packet cmd,
1609 struct drbd_peer_request *peer_req)
1616 dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_w_tfm) ?
1617 crypto_hash_digestsize(mdev->tconn->integrity_w_tfm) : 0;
1619 prepare_header(mdev, &p.head, cmd, sizeof(p) -
1620 sizeof(struct p_header80) +
1621 dgs + peer_req->i.size);
1622 p.sector = cpu_to_be64(peer_req->i.sector);
1623 p.block_id = peer_req->block_id;
1624 p.seq_num = 0; /* unused */
1626 /* Only called by our kernel thread.
1627 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
1628 * in response to admin command or module unload.
1630 if (drbd_get_data_sock(mdev->tconn))
1633 ok = sizeof(p) == drbd_send(mdev->tconn, mdev->tconn->data.socket, &p, sizeof(p), dgs ? MSG_MORE : 0);
1635 dgb = mdev->tconn->int_dig_out;
1636 drbd_csum_ee(mdev, mdev->tconn->integrity_w_tfm, peer_req, dgb);
1637 ok = dgs == drbd_send(mdev->tconn, mdev->tconn->data.socket, dgb, dgs, 0);
1640 ok = !_drbd_send_zc_ee(mdev, peer_req);
1642 drbd_put_data_sock(mdev->tconn);
1647 int drbd_send_oos(struct drbd_conf *mdev, struct drbd_request *req)
1649 struct p_block_desc p;
1651 p.sector = cpu_to_be64(req->i.sector);
1652 p.blksize = cpu_to_be32(req->i.size);
1654 return drbd_send_cmd(mdev, &mdev->tconn->data, P_OUT_OF_SYNC, &p.head, sizeof(p));
1658 drbd_send distinguishes two cases:
1660 Packets sent via the data socket "sock"
1661 and packets sent via the meta data socket "msock"
1664 -----------------+-------------------------+------------------------------
1665 timeout conf.timeout / 2 conf.timeout / 2
1666 timeout action send a ping via msock Abort communication
1667 and close all sockets
1671 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
1673 int drbd_send(struct drbd_tconn *tconn, struct socket *sock,
1674 void *buf, size_t size, unsigned msg_flags)
1683 /* THINK if (signal_pending) return ... ? */
1688 msg.msg_name = NULL;
1689 msg.msg_namelen = 0;
1690 msg.msg_control = NULL;
1691 msg.msg_controllen = 0;
1692 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
1694 if (sock == tconn->data.socket) {
1695 tconn->ko_count = tconn->net_conf->ko_count;
1696 drbd_update_congested(tconn);
1700 * tcp_sendmsg does _not_ use its size parameter at all ?
1702 * -EAGAIN on timeout, -EINTR on signal.
1705 * do we need to block DRBD_SIG if sock == &meta.socket ??
1706 * otherwise wake_asender() might interrupt some send_*Ack !
1708 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
1709 if (rv == -EAGAIN) {
1710 if (we_should_drop_the_connection(tconn, sock))
1716 flush_signals(current);
1724 } while (sent < size);
1726 if (sock == tconn->data.socket)
1727 clear_bit(NET_CONGESTED, &tconn->flags);
1730 if (rv != -EAGAIN) {
1731 conn_err(tconn, "%s_sendmsg returned %d\n",
1732 sock == tconn->meta.socket ? "msock" : "sock",
1734 conn_request_state(tconn, NS(conn, C_BROKEN_PIPE), CS_HARD);
1736 conn_request_state(tconn, NS(conn, C_TIMEOUT), CS_HARD);
1743 * drbd_send_all - Send an entire buffer
1745 * Returns 0 upon success and a negative error value otherwise.
1747 int drbd_send_all(struct drbd_tconn *tconn, struct socket *sock, void *buffer,
1748 size_t size, unsigned msg_flags)
1752 err = drbd_send(tconn, sock, buffer, size, msg_flags);
1760 static int drbd_open(struct block_device *bdev, fmode_t mode)
1762 struct drbd_conf *mdev = bdev->bd_disk->private_data;
1763 unsigned long flags;
1766 mutex_lock(&drbd_main_mutex);
1767 spin_lock_irqsave(&mdev->tconn->req_lock, flags);
1768 /* to have a stable mdev->state.role
1769 * and no race with updating open_cnt */
1771 if (mdev->state.role != R_PRIMARY) {
1772 if (mode & FMODE_WRITE)
1774 else if (!allow_oos)
1780 spin_unlock_irqrestore(&mdev->tconn->req_lock, flags);
1781 mutex_unlock(&drbd_main_mutex);
1786 static int drbd_release(struct gendisk *gd, fmode_t mode)
1788 struct drbd_conf *mdev = gd->private_data;
1789 mutex_lock(&drbd_main_mutex);
1791 mutex_unlock(&drbd_main_mutex);
1795 static void drbd_set_defaults(struct drbd_conf *mdev)
1797 /* Beware! The actual layout differs
1798 * between big endian and little endian */
1799 mdev->state = (union drbd_state) {
1800 { .role = R_SECONDARY,
1802 .conn = C_STANDALONE,
1811 void drbd_init_set_defaults(struct drbd_conf *mdev)
1813 /* the memset(,0,) did most of this.
1814 * note: only assignments, no allocation in here */
1816 drbd_set_defaults(mdev);
1818 atomic_set(&mdev->ap_bio_cnt, 0);
1819 atomic_set(&mdev->ap_pending_cnt, 0);
1820 atomic_set(&mdev->rs_pending_cnt, 0);
1821 atomic_set(&mdev->unacked_cnt, 0);
1822 atomic_set(&mdev->local_cnt, 0);
1823 atomic_set(&mdev->pp_in_use, 0);
1824 atomic_set(&mdev->pp_in_use_by_net, 0);
1825 atomic_set(&mdev->rs_sect_in, 0);
1826 atomic_set(&mdev->rs_sect_ev, 0);
1827 atomic_set(&mdev->ap_in_flight, 0);
1829 mutex_init(&mdev->md_io_mutex);
1830 mutex_init(&mdev->own_state_mutex);
1831 mdev->state_mutex = &mdev->own_state_mutex;
1833 spin_lock_init(&mdev->al_lock);
1834 spin_lock_init(&mdev->peer_seq_lock);
1835 spin_lock_init(&mdev->epoch_lock);
1837 INIT_LIST_HEAD(&mdev->active_ee);
1838 INIT_LIST_HEAD(&mdev->sync_ee);
1839 INIT_LIST_HEAD(&mdev->done_ee);
1840 INIT_LIST_HEAD(&mdev->read_ee);
1841 INIT_LIST_HEAD(&mdev->net_ee);
1842 INIT_LIST_HEAD(&mdev->resync_reads);
1843 INIT_LIST_HEAD(&mdev->resync_work.list);
1844 INIT_LIST_HEAD(&mdev->unplug_work.list);
1845 INIT_LIST_HEAD(&mdev->go_diskless.list);
1846 INIT_LIST_HEAD(&mdev->md_sync_work.list);
1847 INIT_LIST_HEAD(&mdev->start_resync_work.list);
1848 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
1850 mdev->resync_work.cb = w_resync_timer;
1851 mdev->unplug_work.cb = w_send_write_hint;
1852 mdev->go_diskless.cb = w_go_diskless;
1853 mdev->md_sync_work.cb = w_md_sync;
1854 mdev->bm_io_work.w.cb = w_bitmap_io;
1855 mdev->start_resync_work.cb = w_start_resync;
1857 mdev->resync_work.mdev = mdev;
1858 mdev->unplug_work.mdev = mdev;
1859 mdev->go_diskless.mdev = mdev;
1860 mdev->md_sync_work.mdev = mdev;
1861 mdev->bm_io_work.w.mdev = mdev;
1862 mdev->start_resync_work.mdev = mdev;
1864 init_timer(&mdev->resync_timer);
1865 init_timer(&mdev->md_sync_timer);
1866 init_timer(&mdev->start_resync_timer);
1867 init_timer(&mdev->request_timer);
1868 mdev->resync_timer.function = resync_timer_fn;
1869 mdev->resync_timer.data = (unsigned long) mdev;
1870 mdev->md_sync_timer.function = md_sync_timer_fn;
1871 mdev->md_sync_timer.data = (unsigned long) mdev;
1872 mdev->start_resync_timer.function = start_resync_timer_fn;
1873 mdev->start_resync_timer.data = (unsigned long) mdev;
1874 mdev->request_timer.function = request_timer_fn;
1875 mdev->request_timer.data = (unsigned long) mdev;
1877 init_waitqueue_head(&mdev->misc_wait);
1878 init_waitqueue_head(&mdev->state_wait);
1879 init_waitqueue_head(&mdev->ee_wait);
1880 init_waitqueue_head(&mdev->al_wait);
1881 init_waitqueue_head(&mdev->seq_wait);
1883 /* mdev->tconn->agreed_pro_version gets initialized in drbd_connect() */
1884 mdev->write_ordering = WO_bdev_flush;
1885 mdev->resync_wenr = LC_FREE;
1886 mdev->peer_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
1887 mdev->local_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
1890 void drbd_mdev_cleanup(struct drbd_conf *mdev)
1893 if (mdev->tconn->receiver.t_state != NONE)
1894 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
1895 mdev->tconn->receiver.t_state);
1897 /* no need to lock it, I'm the only thread alive */
1898 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
1899 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
1909 mdev->rs_failed = 0;
1910 mdev->rs_last_events = 0;
1911 mdev->rs_last_sect_ev = 0;
1912 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
1913 mdev->rs_mark_left[i] = 0;
1914 mdev->rs_mark_time[i] = 0;
1916 D_ASSERT(mdev->tconn->net_conf == NULL);
1918 drbd_set_my_capacity(mdev, 0);
1920 /* maybe never allocated. */
1921 drbd_bm_resize(mdev, 0, 1);
1922 drbd_bm_cleanup(mdev);
1925 drbd_free_resources(mdev);
1926 clear_bit(AL_SUSPENDED, &mdev->flags);
1929 * currently we drbd_init_ee only on module load, so
1930 * we may do drbd_release_ee only on module unload!
1932 D_ASSERT(list_empty(&mdev->active_ee));
1933 D_ASSERT(list_empty(&mdev->sync_ee));
1934 D_ASSERT(list_empty(&mdev->done_ee));
1935 D_ASSERT(list_empty(&mdev->read_ee));
1936 D_ASSERT(list_empty(&mdev->net_ee));
1937 D_ASSERT(list_empty(&mdev->resync_reads));
1938 D_ASSERT(list_empty(&mdev->tconn->data.work.q));
1939 D_ASSERT(list_empty(&mdev->tconn->meta.work.q));
1940 D_ASSERT(list_empty(&mdev->resync_work.list));
1941 D_ASSERT(list_empty(&mdev->unplug_work.list));
1942 D_ASSERT(list_empty(&mdev->go_diskless.list));
1944 drbd_set_defaults(mdev);
1948 static void drbd_destroy_mempools(void)
1952 while (drbd_pp_pool) {
1953 page = drbd_pp_pool;
1954 drbd_pp_pool = (struct page *)page_private(page);
1959 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
1961 if (drbd_md_io_bio_set)
1962 bioset_free(drbd_md_io_bio_set);
1963 if (drbd_md_io_page_pool)
1964 mempool_destroy(drbd_md_io_page_pool);
1965 if (drbd_ee_mempool)
1966 mempool_destroy(drbd_ee_mempool);
1967 if (drbd_request_mempool)
1968 mempool_destroy(drbd_request_mempool);
1970 kmem_cache_destroy(drbd_ee_cache);
1971 if (drbd_request_cache)
1972 kmem_cache_destroy(drbd_request_cache);
1973 if (drbd_bm_ext_cache)
1974 kmem_cache_destroy(drbd_bm_ext_cache);
1975 if (drbd_al_ext_cache)
1976 kmem_cache_destroy(drbd_al_ext_cache);
1978 drbd_md_io_bio_set = NULL;
1979 drbd_md_io_page_pool = NULL;
1980 drbd_ee_mempool = NULL;
1981 drbd_request_mempool = NULL;
1982 drbd_ee_cache = NULL;
1983 drbd_request_cache = NULL;
1984 drbd_bm_ext_cache = NULL;
1985 drbd_al_ext_cache = NULL;
1990 static int drbd_create_mempools(void)
1993 const int number = (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count;
1996 /* prepare our caches and mempools */
1997 drbd_request_mempool = NULL;
1998 drbd_ee_cache = NULL;
1999 drbd_request_cache = NULL;
2000 drbd_bm_ext_cache = NULL;
2001 drbd_al_ext_cache = NULL;
2002 drbd_pp_pool = NULL;
2003 drbd_md_io_page_pool = NULL;
2004 drbd_md_io_bio_set = NULL;
2007 drbd_request_cache = kmem_cache_create(
2008 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
2009 if (drbd_request_cache == NULL)
2012 drbd_ee_cache = kmem_cache_create(
2013 "drbd_ee", sizeof(struct drbd_peer_request), 0, 0, NULL);
2014 if (drbd_ee_cache == NULL)
2017 drbd_bm_ext_cache = kmem_cache_create(
2018 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
2019 if (drbd_bm_ext_cache == NULL)
2022 drbd_al_ext_cache = kmem_cache_create(
2023 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
2024 if (drbd_al_ext_cache == NULL)
2028 drbd_md_io_bio_set = bioset_create(DRBD_MIN_POOL_PAGES, 0);
2029 if (drbd_md_io_bio_set == NULL)
2032 drbd_md_io_page_pool = mempool_create_page_pool(DRBD_MIN_POOL_PAGES, 0);
2033 if (drbd_md_io_page_pool == NULL)
2036 drbd_request_mempool = mempool_create(number,
2037 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
2038 if (drbd_request_mempool == NULL)
2041 drbd_ee_mempool = mempool_create(number,
2042 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2043 if (drbd_ee_mempool == NULL)
2046 /* drbd's page pool */
2047 spin_lock_init(&drbd_pp_lock);
2049 for (i = 0; i < number; i++) {
2050 page = alloc_page(GFP_HIGHUSER);
2053 set_page_private(page, (unsigned long)drbd_pp_pool);
2054 drbd_pp_pool = page;
2056 drbd_pp_vacant = number;
2061 drbd_destroy_mempools(); /* in case we allocated some */
2065 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
2068 /* just so we have it. you never know what interesting things we
2069 * might want to do here some day...
2075 static struct notifier_block drbd_notifier = {
2076 .notifier_call = drbd_notify_sys,
2079 static void drbd_release_ee_lists(struct drbd_conf *mdev)
2083 rr = drbd_release_ee(mdev, &mdev->active_ee);
2085 dev_err(DEV, "%d EEs in active list found!\n", rr);
2087 rr = drbd_release_ee(mdev, &mdev->sync_ee);
2089 dev_err(DEV, "%d EEs in sync list found!\n", rr);
2091 rr = drbd_release_ee(mdev, &mdev->read_ee);
2093 dev_err(DEV, "%d EEs in read list found!\n", rr);
2095 rr = drbd_release_ee(mdev, &mdev->done_ee);
2097 dev_err(DEV, "%d EEs in done list found!\n", rr);
2099 rr = drbd_release_ee(mdev, &mdev->net_ee);
2101 dev_err(DEV, "%d EEs in net list found!\n", rr);
2104 /* caution. no locking. */
2105 void drbd_delete_device(unsigned int minor)
2107 struct drbd_conf *mdev = minor_to_mdev(minor);
2112 idr_remove(&mdev->tconn->volumes, mdev->vnr);
2113 idr_remove(&minors, minor);
2116 /* paranoia asserts */
2117 D_ASSERT(mdev->open_cnt == 0);
2118 D_ASSERT(list_empty(&mdev->tconn->data.work.q));
2119 /* end paranoia asserts */
2121 del_gendisk(mdev->vdisk);
2123 /* cleanup stuff that may have been allocated during
2124 * device (re-)configuration or state changes */
2126 if (mdev->this_bdev)
2127 bdput(mdev->this_bdev);
2129 drbd_free_resources(mdev);
2131 drbd_release_ee_lists(mdev);
2133 lc_destroy(mdev->act_log);
2134 lc_destroy(mdev->resync);
2136 kfree(mdev->p_uuid);
2137 /* mdev->p_uuid = NULL; */
2139 /* cleanup the rest that has been
2140 * allocated from drbd_new_device
2141 * and actually free the mdev itself */
2142 drbd_free_mdev(mdev);
2145 static void drbd_cleanup(void)
2148 struct drbd_conf *mdev;
2150 unregister_reboot_notifier(&drbd_notifier);
2152 /* first remove proc,
2153 * drbdsetup uses it's presence to detect
2154 * whether DRBD is loaded.
2155 * If we would get stuck in proc removal,
2156 * but have netlink already deregistered,
2157 * some drbdsetup commands may wait forever
2161 remove_proc_entry("drbd", NULL);
2163 drbd_genl_unregister();
2165 idr_for_each_entry(&minors, mdev, i)
2166 drbd_delete_device(i);
2167 drbd_destroy_mempools();
2168 unregister_blkdev(DRBD_MAJOR, "drbd");
2170 idr_destroy(&minors);
2172 printk(KERN_INFO "drbd: module cleanup done.\n");
2176 * drbd_congested() - Callback for pdflush
2177 * @congested_data: User data
2178 * @bdi_bits: Bits pdflush is currently interested in
2180 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
2182 static int drbd_congested(void *congested_data, int bdi_bits)
2184 struct drbd_conf *mdev = congested_data;
2185 struct request_queue *q;
2189 if (!may_inc_ap_bio(mdev)) {
2190 /* DRBD has frozen IO */
2196 if (get_ldev(mdev)) {
2197 q = bdev_get_queue(mdev->ldev->backing_bdev);
2198 r = bdi_congested(&q->backing_dev_info, bdi_bits);
2204 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->tconn->flags)) {
2205 r |= (1 << BDI_async_congested);
2206 reason = reason == 'b' ? 'a' : 'n';
2210 mdev->congestion_reason = reason;
2214 static void drbd_init_workqueue(struct drbd_work_queue* wq)
2216 sema_init(&wq->s, 0);
2217 spin_lock_init(&wq->q_lock);
2218 INIT_LIST_HEAD(&wq->q);
2221 struct drbd_tconn *conn_by_name(const char *name)
2223 struct drbd_tconn *tconn;
2225 if (!name || !name[0])
2228 mutex_lock(&drbd_cfg_mutex);
2229 list_for_each_entry(tconn, &drbd_tconns, all_tconn) {
2230 if (!strcmp(tconn->name, name))
2235 mutex_unlock(&drbd_cfg_mutex);
2239 struct drbd_tconn *drbd_new_tconn(const char *name)
2241 struct drbd_tconn *tconn;
2243 tconn = kzalloc(sizeof(struct drbd_tconn), GFP_KERNEL);
2247 tconn->name = kstrdup(name, GFP_KERNEL);
2251 if (!zalloc_cpumask_var(&tconn->cpu_mask, GFP_KERNEL))
2254 if (!tl_init(tconn))
2257 tconn->cstate = C_STANDALONE;
2258 mutex_init(&tconn->cstate_mutex);
2259 spin_lock_init(&tconn->req_lock);
2260 atomic_set(&tconn->net_cnt, 0);
2261 init_waitqueue_head(&tconn->net_cnt_wait);
2262 init_waitqueue_head(&tconn->ping_wait);
2263 idr_init(&tconn->volumes);
2265 drbd_init_workqueue(&tconn->data.work);
2266 mutex_init(&tconn->data.mutex);
2268 drbd_init_workqueue(&tconn->meta.work);
2269 mutex_init(&tconn->meta.mutex);
2271 drbd_thread_init(tconn, &tconn->receiver, drbdd_init, "receiver");
2272 drbd_thread_init(tconn, &tconn->worker, drbd_worker, "worker");
2273 drbd_thread_init(tconn, &tconn->asender, drbd_asender, "asender");
2275 tconn->res_opts = (struct res_opts) {
2276 {}, 0, /* cpu_mask */
2277 DRBD_ON_NO_DATA_DEF, /* on_no_data */
2280 mutex_lock(&drbd_cfg_mutex);
2281 list_add_tail(&tconn->all_tconn, &drbd_tconns);
2282 mutex_unlock(&drbd_cfg_mutex);
2288 free_cpumask_var(tconn->cpu_mask);
2295 void drbd_free_tconn(struct drbd_tconn *tconn)
2297 list_del(&tconn->all_tconn);
2298 idr_destroy(&tconn->volumes);
2300 free_cpumask_var(tconn->cpu_mask);
2302 kfree(tconn->int_dig_out);
2303 kfree(tconn->int_dig_in);
2304 kfree(tconn->int_dig_vv);
2308 enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor, int vnr)
2310 struct drbd_conf *mdev;
2311 struct gendisk *disk;
2312 struct request_queue *q;
2314 int minor_got = minor;
2315 enum drbd_ret_code err = ERR_NOMEM;
2317 mdev = minor_to_mdev(minor);
2319 return ERR_MINOR_EXISTS;
2321 /* GFP_KERNEL, we are outside of all write-out paths */
2322 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
2326 mdev->tconn = tconn;
2327 mdev->minor = minor;
2330 drbd_init_set_defaults(mdev);
2332 q = blk_alloc_queue(GFP_KERNEL);
2336 q->queuedata = mdev;
2338 disk = alloc_disk(1);
2343 set_disk_ro(disk, true);
2346 disk->major = DRBD_MAJOR;
2347 disk->first_minor = minor;
2348 disk->fops = &drbd_ops;
2349 sprintf(disk->disk_name, "drbd%d", minor);
2350 disk->private_data = mdev;
2352 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
2353 /* we have no partitions. we contain only ourselves. */
2354 mdev->this_bdev->bd_contains = mdev->this_bdev;
2356 q->backing_dev_info.congested_fn = drbd_congested;
2357 q->backing_dev_info.congested_data = mdev;
2359 blk_queue_make_request(q, drbd_make_request);
2360 /* Setting the max_hw_sectors to an odd value of 8kibyte here
2361 This triggers a max_bio_size message upon first attach or connect */
2362 blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8);
2363 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
2364 blk_queue_merge_bvec(q, drbd_merge_bvec);
2365 q->queue_lock = &mdev->tconn->req_lock; /* needed since we use */
2367 mdev->md_io_page = alloc_page(GFP_KERNEL);
2368 if (!mdev->md_io_page)
2369 goto out_no_io_page;
2371 if (drbd_bm_init(mdev))
2373 mdev->read_requests = RB_ROOT;
2374 mdev->write_requests = RB_ROOT;
2376 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
2377 if (!mdev->current_epoch)
2380 INIT_LIST_HEAD(&mdev->current_epoch->list);
2383 if (!idr_pre_get(&minors, GFP_KERNEL))
2384 goto out_no_minor_idr;
2385 if (idr_get_new_above(&minors, mdev, minor, &minor_got))
2386 goto out_no_minor_idr;
2387 if (minor_got != minor) {
2388 err = ERR_MINOR_EXISTS;
2389 drbd_msg_put_info("requested minor exists already");
2390 goto out_idr_remove_minor;
2393 if (!idr_pre_get(&tconn->volumes, GFP_KERNEL))
2394 goto out_idr_remove_minor;
2395 if (idr_get_new_above(&tconn->volumes, mdev, vnr, &vnr_got))
2396 goto out_idr_remove_minor;
2397 if (vnr_got != vnr) {
2398 err = ERR_INVALID_REQUEST;
2399 drbd_msg_put_info("requested volume exists already");
2400 goto out_idr_remove_vol;
2404 /* inherit the connection state */
2405 mdev->state.conn = tconn->cstate;
2406 if (mdev->state.conn == C_WF_REPORT_PARAMS)
2407 drbd_connected(vnr, mdev, tconn);
2412 idr_remove(&tconn->volumes, vnr_got);
2413 out_idr_remove_minor:
2414 idr_remove(&minors, minor_got);
2417 kfree(mdev->current_epoch);
2419 drbd_bm_cleanup(mdev);
2421 __free_page(mdev->md_io_page);
2425 blk_cleanup_queue(q);
2431 /* counterpart of drbd_new_device.
2432 * last part of drbd_delete_device. */
2433 void drbd_free_mdev(struct drbd_conf *mdev)
2435 kfree(mdev->current_epoch);
2436 if (mdev->bitmap) /* should no longer be there. */
2437 drbd_bm_cleanup(mdev);
2438 __free_page(mdev->md_io_page);
2439 put_disk(mdev->vdisk);
2440 blk_cleanup_queue(mdev->rq_queue);
2445 int __init drbd_init(void)
2449 BUILD_BUG_ON(sizeof(struct p_header80) != sizeof(struct p_header95));
2450 BUILD_BUG_ON(sizeof(struct p_handshake) != 80);
2452 if (minor_count < DRBD_MINOR_COUNT_MIN || minor_count > DRBD_MINOR_COUNT_MAX) {
2454 "drbd: invalid minor_count (%d)\n", minor_count);
2462 err = register_blkdev(DRBD_MAJOR, "drbd");
2465 "drbd: unable to register block device major %d\n",
2470 err = drbd_genl_register();
2472 printk(KERN_ERR "drbd: unable to register generic netlink family\n");
2477 register_reboot_notifier(&drbd_notifier);
2480 * allocate all necessary structs
2484 init_waitqueue_head(&drbd_pp_wait);
2486 drbd_proc = NULL; /* play safe for drbd_cleanup */
2489 err = drbd_create_mempools();
2493 drbd_proc = proc_create_data("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops, NULL);
2495 printk(KERN_ERR "drbd: unable to register proc file\n");
2499 rwlock_init(&global_state_lock);
2500 INIT_LIST_HEAD(&drbd_tconns);
2502 printk(KERN_INFO "drbd: initialized. "
2503 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
2504 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
2505 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
2506 printk(KERN_INFO "drbd: registered as block device major %d\n",
2509 return 0; /* Success! */
2514 /* currently always the case */
2515 printk(KERN_ERR "drbd: ran out of memory\n");
2517 printk(KERN_ERR "drbd: initialization failure\n");
2521 void drbd_free_bc(struct drbd_backing_dev *ldev)
2526 blkdev_put(ldev->backing_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
2527 blkdev_put(ldev->md_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
2532 void drbd_free_sock(struct drbd_tconn *tconn)
2534 if (tconn->data.socket) {
2535 mutex_lock(&tconn->data.mutex);
2536 kernel_sock_shutdown(tconn->data.socket, SHUT_RDWR);
2537 sock_release(tconn->data.socket);
2538 tconn->data.socket = NULL;
2539 mutex_unlock(&tconn->data.mutex);
2541 if (tconn->meta.socket) {
2542 mutex_lock(&tconn->meta.mutex);
2543 kernel_sock_shutdown(tconn->meta.socket, SHUT_RDWR);
2544 sock_release(tconn->meta.socket);
2545 tconn->meta.socket = NULL;
2546 mutex_unlock(&tconn->meta.mutex);
2551 void drbd_free_resources(struct drbd_conf *mdev)
2553 crypto_free_hash(mdev->tconn->csums_tfm);
2554 mdev->tconn->csums_tfm = NULL;
2555 crypto_free_hash(mdev->tconn->verify_tfm);
2556 mdev->tconn->verify_tfm = NULL;
2557 crypto_free_hash(mdev->tconn->cram_hmac_tfm);
2558 mdev->tconn->cram_hmac_tfm = NULL;
2559 crypto_free_hash(mdev->tconn->integrity_w_tfm);
2560 mdev->tconn->integrity_w_tfm = NULL;
2561 crypto_free_hash(mdev->tconn->integrity_r_tfm);
2562 mdev->tconn->integrity_r_tfm = NULL;
2564 drbd_free_sock(mdev->tconn);
2567 drbd_free_bc(mdev->ldev);
2568 mdev->ldev = NULL;);
2571 /* meta data management */
2573 struct meta_data_on_disk {
2574 u64 la_size; /* last agreed size. */
2575 u64 uuid[UI_SIZE]; /* UUIDs. */
2578 u32 flags; /* MDF */
2581 u32 al_offset; /* offset to this block */
2582 u32 al_nr_extents; /* important for restoring the AL */
2583 /* `-- act_log->nr_elements <-- ldev->dc.al_extents */
2584 u32 bm_offset; /* offset to the bitmap, from here */
2585 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
2586 u32 la_peer_max_bio_size; /* last peer max_bio_size */
2587 u32 reserved_u32[3];
2592 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
2593 * @mdev: DRBD device.
2595 void drbd_md_sync(struct drbd_conf *mdev)
2597 struct meta_data_on_disk *buffer;
2601 del_timer(&mdev->md_sync_timer);
2602 /* timer may be rearmed by drbd_md_mark_dirty() now. */
2603 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
2606 /* We use here D_FAILED and not D_ATTACHING because we try to write
2607 * metadata even if we detach due to a disk failure! */
2608 if (!get_ldev_if_state(mdev, D_FAILED))
2611 mutex_lock(&mdev->md_io_mutex);
2612 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
2613 memset(buffer, 0, 512);
2615 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
2616 for (i = UI_CURRENT; i < UI_SIZE; i++)
2617 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
2618 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
2619 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
2621 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
2622 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
2623 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
2624 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
2625 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
2627 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
2628 buffer->la_peer_max_bio_size = cpu_to_be32(mdev->peer_max_bio_size);
2630 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
2631 sector = mdev->ldev->md.md_offset;
2633 if (!drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
2634 /* this was a try anyways ... */
2635 dev_err(DEV, "meta data update failed!\n");
2636 drbd_chk_io_error(mdev, 1, true);
2639 /* Update mdev->ldev->md.la_size_sect,
2640 * since we updated it on metadata. */
2641 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
2643 mutex_unlock(&mdev->md_io_mutex);
2648 * drbd_md_read() - Reads in the meta data super block
2649 * @mdev: DRBD device.
2650 * @bdev: Device from which the meta data should be read in.
2652 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_code in case
2653 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
2655 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
2657 struct meta_data_on_disk *buffer;
2658 int i, rv = NO_ERROR;
2660 if (!get_ldev_if_state(mdev, D_ATTACHING))
2661 return ERR_IO_MD_DISK;
2663 mutex_lock(&mdev->md_io_mutex);
2664 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
2666 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
2667 /* NOTE: can't do normal error processing here as this is
2668 called BEFORE disk is attached */
2669 dev_err(DEV, "Error while reading metadata.\n");
2670 rv = ERR_IO_MD_DISK;
2674 if (buffer->magic != cpu_to_be32(DRBD_MD_MAGIC)) {
2675 dev_err(DEV, "Error while reading metadata, magic not found.\n");
2676 rv = ERR_MD_INVALID;
2679 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
2680 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
2681 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
2682 rv = ERR_MD_INVALID;
2685 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
2686 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
2687 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
2688 rv = ERR_MD_INVALID;
2691 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
2692 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
2693 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
2694 rv = ERR_MD_INVALID;
2698 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
2699 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
2700 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
2701 rv = ERR_MD_INVALID;
2705 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
2706 for (i = UI_CURRENT; i < UI_SIZE; i++)
2707 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
2708 bdev->md.flags = be32_to_cpu(buffer->flags);
2709 bdev->dc.al_extents = be32_to_cpu(buffer->al_nr_extents);
2710 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
2712 spin_lock_irq(&mdev->tconn->req_lock);
2713 if (mdev->state.conn < C_CONNECTED) {
2715 peer = be32_to_cpu(buffer->la_peer_max_bio_size);
2716 peer = max_t(int, peer, DRBD_MAX_BIO_SIZE_SAFE);
2717 mdev->peer_max_bio_size = peer;
2719 spin_unlock_irq(&mdev->tconn->req_lock);
2721 if (bdev->dc.al_extents < 7)
2722 bdev->dc.al_extents = 127;
2725 mutex_unlock(&mdev->md_io_mutex);
2732 * drbd_md_mark_dirty() - Mark meta data super block as dirty
2733 * @mdev: DRBD device.
2735 * Call this function if you change anything that should be written to
2736 * the meta-data super block. This function sets MD_DIRTY, and starts a
2737 * timer that ensures that within five seconds you have to call drbd_md_sync().
2740 void drbd_md_mark_dirty_(struct drbd_conf *mdev, unsigned int line, const char *func)
2742 if (!test_and_set_bit(MD_DIRTY, &mdev->flags)) {
2743 mod_timer(&mdev->md_sync_timer, jiffies + HZ);
2744 mdev->last_md_mark_dirty.line = line;
2745 mdev->last_md_mark_dirty.func = func;
2749 void drbd_md_mark_dirty(struct drbd_conf *mdev)
2751 if (!test_and_set_bit(MD_DIRTY, &mdev->flags))
2752 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
2756 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
2760 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
2761 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
2764 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
2766 if (idx == UI_CURRENT) {
2767 if (mdev->state.role == R_PRIMARY)
2772 drbd_set_ed_uuid(mdev, val);
2775 mdev->ldev->md.uuid[idx] = val;
2776 drbd_md_mark_dirty(mdev);
2780 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
2782 if (mdev->ldev->md.uuid[idx]) {
2783 drbd_uuid_move_history(mdev);
2784 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
2786 _drbd_uuid_set(mdev, idx, val);
2790 * drbd_uuid_new_current() - Creates a new current UUID
2791 * @mdev: DRBD device.
2793 * Creates a new current UUID, and rotates the old current UUID into
2794 * the bitmap slot. Causes an incremental resync upon next connect.
2796 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
2799 unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];
2802 dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
2804 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
2806 get_random_bytes(&val, sizeof(u64));
2807 _drbd_uuid_set(mdev, UI_CURRENT, val);
2808 drbd_print_uuids(mdev, "new current UUID");
2809 /* get it to stable storage _now_ */
2813 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
2815 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
2819 drbd_uuid_move_history(mdev);
2820 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
2821 mdev->ldev->md.uuid[UI_BITMAP] = 0;
2823 unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];
2825 dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
2827 mdev->ldev->md.uuid[UI_BITMAP] = val & ~((u64)1);
2829 drbd_md_mark_dirty(mdev);
2833 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
2834 * @mdev: DRBD device.
2836 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
2838 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
2842 if (get_ldev_if_state(mdev, D_ATTACHING)) {
2843 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
2845 drbd_bm_set_all(mdev);
2847 rv = drbd_bm_write(mdev);
2850 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2861 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
2862 * @mdev: DRBD device.
2864 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
2866 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
2870 drbd_resume_al(mdev);
2871 if (get_ldev_if_state(mdev, D_ATTACHING)) {
2872 drbd_bm_clear_all(mdev);
2873 rv = drbd_bm_write(mdev);
2880 static int w_bitmap_io(struct drbd_work *w, int unused)
2882 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
2883 struct drbd_conf *mdev = w->mdev;
2886 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
2888 if (get_ldev(mdev)) {
2889 drbd_bm_lock(mdev, work->why, work->flags);
2890 rv = work->io_fn(mdev);
2891 drbd_bm_unlock(mdev);
2895 clear_bit_unlock(BITMAP_IO, &mdev->flags);
2896 wake_up(&mdev->misc_wait);
2899 work->done(mdev, rv);
2901 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
2908 void drbd_ldev_destroy(struct drbd_conf *mdev)
2910 lc_destroy(mdev->resync);
2911 mdev->resync = NULL;
2912 lc_destroy(mdev->act_log);
2913 mdev->act_log = NULL;
2915 drbd_free_bc(mdev->ldev);
2916 mdev->ldev = NULL;);
2918 clear_bit(GO_DISKLESS, &mdev->flags);
2921 static int w_go_diskless(struct drbd_work *w, int unused)
2923 struct drbd_conf *mdev = w->mdev;
2925 D_ASSERT(mdev->state.disk == D_FAILED);
2926 /* we cannot assert local_cnt == 0 here, as get_ldev_if_state will
2927 * inc/dec it frequently. Once we are D_DISKLESS, no one will touch
2928 * the protected members anymore, though, so once put_ldev reaches zero
2929 * again, it will be safe to free them. */
2930 drbd_force_state(mdev, NS(disk, D_DISKLESS));
2934 void drbd_go_diskless(struct drbd_conf *mdev)
2936 D_ASSERT(mdev->state.disk == D_FAILED);
2937 if (!test_and_set_bit(GO_DISKLESS, &mdev->flags))
2938 drbd_queue_work(&mdev->tconn->data.work, &mdev->go_diskless);
2942 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
2943 * @mdev: DRBD device.
2944 * @io_fn: IO callback to be called when bitmap IO is possible
2945 * @done: callback to be called after the bitmap IO was performed
2946 * @why: Descriptive text of the reason for doing the IO
2948 * While IO on the bitmap happens we freeze application IO thus we ensure
2949 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
2950 * called from worker context. It MUST NOT be used while a previous such
2951 * work is still pending!
2953 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
2954 int (*io_fn)(struct drbd_conf *),
2955 void (*done)(struct drbd_conf *, int),
2956 char *why, enum bm_flag flags)
2958 D_ASSERT(current == mdev->tconn->worker.task);
2960 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
2961 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
2962 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
2963 if (mdev->bm_io_work.why)
2964 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
2965 why, mdev->bm_io_work.why);
2967 mdev->bm_io_work.io_fn = io_fn;
2968 mdev->bm_io_work.done = done;
2969 mdev->bm_io_work.why = why;
2970 mdev->bm_io_work.flags = flags;
2972 spin_lock_irq(&mdev->tconn->req_lock);
2973 set_bit(BITMAP_IO, &mdev->flags);
2974 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
2975 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
2976 drbd_queue_work(&mdev->tconn->data.work, &mdev->bm_io_work.w);
2978 spin_unlock_irq(&mdev->tconn->req_lock);
2982 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
2983 * @mdev: DRBD device.
2984 * @io_fn: IO callback to be called when bitmap IO is possible
2985 * @why: Descriptive text of the reason for doing the IO
2987 * freezes application IO while that the actual IO operations runs. This
2988 * functions MAY NOT be called from worker context.
2990 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *),
2991 char *why, enum bm_flag flags)
2995 D_ASSERT(current != mdev->tconn->worker.task);
2997 if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
2998 drbd_suspend_io(mdev);
3000 drbd_bm_lock(mdev, why, flags);
3002 drbd_bm_unlock(mdev);
3004 if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
3005 drbd_resume_io(mdev);
3010 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3012 if ((mdev->ldev->md.flags & flag) != flag) {
3013 drbd_md_mark_dirty(mdev);
3014 mdev->ldev->md.flags |= flag;
3018 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3020 if ((mdev->ldev->md.flags & flag) != 0) {
3021 drbd_md_mark_dirty(mdev);
3022 mdev->ldev->md.flags &= ~flag;
3025 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
3027 return (bdev->md.flags & flag) != 0;
3030 static void md_sync_timer_fn(unsigned long data)
3032 struct drbd_conf *mdev = (struct drbd_conf *) data;
3034 drbd_queue_work_front(&mdev->tconn->data.work, &mdev->md_sync_work);
3037 static int w_md_sync(struct drbd_work *w, int unused)
3039 struct drbd_conf *mdev = w->mdev;
3041 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3043 dev_warn(DEV, "last md_mark_dirty: %s:%u\n",
3044 mdev->last_md_mark_dirty.func, mdev->last_md_mark_dirty.line);
3050 const char *cmdname(enum drbd_packet cmd)
3052 /* THINK may need to become several global tables
3053 * when we want to support more than
3054 * one PRO_VERSION */
3055 static const char *cmdnames[] = {
3057 [P_DATA_REPLY] = "DataReply",
3058 [P_RS_DATA_REPLY] = "RSDataReply",
3059 [P_BARRIER] = "Barrier",
3060 [P_BITMAP] = "ReportBitMap",
3061 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget",
3062 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource",
3063 [P_UNPLUG_REMOTE] = "UnplugRemote",
3064 [P_DATA_REQUEST] = "DataRequest",
3065 [P_RS_DATA_REQUEST] = "RSDataRequest",
3066 [P_SYNC_PARAM] = "SyncParam",
3067 [P_SYNC_PARAM89] = "SyncParam89",
3068 [P_PROTOCOL] = "ReportProtocol",
3069 [P_UUIDS] = "ReportUUIDs",
3070 [P_SIZES] = "ReportSizes",
3071 [P_STATE] = "ReportState",
3072 [P_SYNC_UUID] = "ReportSyncUUID",
3073 [P_AUTH_CHALLENGE] = "AuthChallenge",
3074 [P_AUTH_RESPONSE] = "AuthResponse",
3076 [P_PING_ACK] = "PingAck",
3077 [P_RECV_ACK] = "RecvAck",
3078 [P_WRITE_ACK] = "WriteAck",
3079 [P_RS_WRITE_ACK] = "RSWriteAck",
3080 [P_DISCARD_WRITE] = "DiscardWrite",
3081 [P_NEG_ACK] = "NegAck",
3082 [P_NEG_DREPLY] = "NegDReply",
3083 [P_NEG_RS_DREPLY] = "NegRSDReply",
3084 [P_BARRIER_ACK] = "BarrierAck",
3085 [P_STATE_CHG_REQ] = "StateChgRequest",
3086 [P_STATE_CHG_REPLY] = "StateChgReply",
3087 [P_OV_REQUEST] = "OVRequest",
3088 [P_OV_REPLY] = "OVReply",
3089 [P_OV_RESULT] = "OVResult",
3090 [P_CSUM_RS_REQUEST] = "CsumRSRequest",
3091 [P_RS_IS_IN_SYNC] = "CsumRSIsInSync",
3092 [P_COMPRESSED_BITMAP] = "CBitmap",
3093 [P_DELAY_PROBE] = "DelayProbe",
3094 [P_OUT_OF_SYNC] = "OutOfSync",
3095 [P_RETRY_WRITE] = "RetryWrite",
3098 if (cmd == P_HAND_SHAKE_M)
3099 return "HandShakeM";
3100 if (cmd == P_HAND_SHAKE_S)
3101 return "HandShakeS";
3102 if (cmd == P_HAND_SHAKE)
3104 if (cmd >= ARRAY_SIZE(cmdnames))
3106 return cmdnames[cmd];
3110 * drbd_wait_misc - wait for a request to make progress
3111 * @mdev: device associated with the request
3112 * @i: the struct drbd_interval embedded in struct drbd_request or
3113 * struct drbd_peer_request
3115 int drbd_wait_misc(struct drbd_conf *mdev, struct drbd_interval *i)
3117 struct net_conf *net_conf = mdev->tconn->net_conf;
3123 timeout = MAX_SCHEDULE_TIMEOUT;
3124 if (net_conf->ko_count)
3125 timeout = net_conf->timeout * HZ / 10 * net_conf->ko_count;
3127 /* Indicate to wake up mdev->misc_wait on progress. */
3129 prepare_to_wait(&mdev->misc_wait, &wait, TASK_INTERRUPTIBLE);
3130 spin_unlock_irq(&mdev->tconn->req_lock);
3131 timeout = schedule_timeout(timeout);
3132 finish_wait(&mdev->misc_wait, &wait);
3133 spin_lock_irq(&mdev->tconn->req_lock);
3134 if (!timeout || mdev->state.conn < C_CONNECTED)
3136 if (signal_pending(current))
3137 return -ERESTARTSYS;
3141 #ifdef CONFIG_DRBD_FAULT_INJECTION
3142 /* Fault insertion support including random number generator shamelessly
3143 * stolen from kernel/rcutorture.c */
3144 struct fault_random_state {
3145 unsigned long state;
3146 unsigned long count;
3149 #define FAULT_RANDOM_MULT 39916801 /* prime */
3150 #define FAULT_RANDOM_ADD 479001701 /* prime */
3151 #define FAULT_RANDOM_REFRESH 10000
3154 * Crude but fast random-number generator. Uses a linear congruential
3155 * generator, with occasional help from get_random_bytes().
3157 static unsigned long
3158 _drbd_fault_random(struct fault_random_state *rsp)
3162 if (!rsp->count--) {
3163 get_random_bytes(&refresh, sizeof(refresh));
3164 rsp->state += refresh;
3165 rsp->count = FAULT_RANDOM_REFRESH;
3167 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
3168 return swahw32(rsp->state);
3172 _drbd_fault_str(unsigned int type) {
3173 static char *_faults[] = {
3174 [DRBD_FAULT_MD_WR] = "Meta-data write",
3175 [DRBD_FAULT_MD_RD] = "Meta-data read",
3176 [DRBD_FAULT_RS_WR] = "Resync write",
3177 [DRBD_FAULT_RS_RD] = "Resync read",
3178 [DRBD_FAULT_DT_WR] = "Data write",
3179 [DRBD_FAULT_DT_RD] = "Data read",
3180 [DRBD_FAULT_DT_RA] = "Data read ahead",
3181 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
3182 [DRBD_FAULT_AL_EE] = "EE allocation",
3183 [DRBD_FAULT_RECEIVE] = "receive data corruption",
3186 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
3190 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
3192 static struct fault_random_state rrs = {0, 0};
3194 unsigned int ret = (
3196 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
3197 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
3202 if (__ratelimit(&drbd_ratelimit_state))
3203 dev_warn(DEV, "***Simulating %s failure\n",
3204 _drbd_fault_str(type));
3211 const char *drbd_buildtag(void)
3213 /* DRBD built from external sources has here a reference to the
3214 git hash of the source code. */
3216 static char buildtag[38] = "\0uilt-in";
3218 if (buildtag[0] == 0) {
3219 #ifdef CONFIG_MODULES
3220 if (THIS_MODULE != NULL)
3221 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
3230 module_init(drbd_init)
3231 module_exit(drbd_cleanup)
3233 EXPORT_SYMBOL(drbd_conn_str);
3234 EXPORT_SYMBOL(drbd_role_str);
3235 EXPORT_SYMBOL(drbd_disk_str);
3236 EXPORT_SYMBOL(drbd_set_st_err_str);