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);
1333 ok = (sizeof(p) == drbd_send(mdev->tconn, mdev->tconn->data.socket, &p, sizeof(p), 0));
1334 ok = ok && (digest_size == drbd_send(mdev->tconn, mdev->tconn->data.socket, digest, digest_size, 0));
1336 mutex_unlock(&mdev->tconn->data.mutex);
1341 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
1343 struct p_block_req p;
1345 p.sector = cpu_to_be64(sector);
1346 p.block_id = ID_SYNCER /* unused */;
1347 p.blksize = cpu_to_be32(size);
1349 return drbd_send_cmd(mdev, &mdev->tconn->data, P_OV_REQUEST, &p.head, sizeof(p));
1352 /* called on sndtimeo
1353 * returns false if we should retry,
1354 * true if we think connection is dead
1356 static int we_should_drop_the_connection(struct drbd_tconn *tconn, struct socket *sock)
1359 /* long elapsed = (long)(jiffies - mdev->last_received); */
1361 drop_it = tconn->meta.socket == sock
1362 || !tconn->asender.task
1363 || get_t_state(&tconn->asender) != RUNNING
1364 || tconn->cstate < C_WF_REPORT_PARAMS;
1369 drop_it = !--tconn->ko_count;
1371 conn_err(tconn, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
1372 current->comm, current->pid, tconn->ko_count);
1373 request_ping(tconn);
1376 return drop_it; /* && (mdev->state == R_PRIMARY) */;
1379 static void drbd_update_congested(struct drbd_tconn *tconn)
1381 struct sock *sk = tconn->data.socket->sk;
1382 if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5)
1383 set_bit(NET_CONGESTED, &tconn->flags);
1386 /* The idea of sendpage seems to be to put some kind of reference
1387 * to the page into the skb, and to hand it over to the NIC. In
1388 * this process get_page() gets called.
1390 * As soon as the page was really sent over the network put_page()
1391 * gets called by some part of the network layer. [ NIC driver? ]
1393 * [ get_page() / put_page() increment/decrement the count. If count
1394 * reaches 0 the page will be freed. ]
1396 * This works nicely with pages from FSs.
1397 * But this means that in protocol A we might signal IO completion too early!
1399 * In order not to corrupt data during a resync we must make sure
1400 * that we do not reuse our own buffer pages (EEs) to early, therefore
1401 * we have the net_ee list.
1403 * XFS seems to have problems, still, it submits pages with page_count == 0!
1404 * As a workaround, we disable sendpage on pages
1405 * with page_count == 0 or PageSlab.
1407 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
1408 int offset, size_t size, unsigned msg_flags)
1410 int sent = drbd_send(mdev->tconn, mdev->tconn->data.socket, kmap(page) + offset, size, msg_flags);
1413 mdev->send_cnt += size>>9;
1414 return sent == size;
1417 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
1418 int offset, size_t size, unsigned msg_flags)
1420 mm_segment_t oldfs = get_fs();
1424 /* e.g. XFS meta- & log-data is in slab pages, which have a
1425 * page_count of 0 and/or have PageSlab() set.
1426 * we cannot use send_page for those, as that does get_page();
1427 * put_page(); and would cause either a VM_BUG directly, or
1428 * __page_cache_release a page that would actually still be referenced
1429 * by someone, leading to some obscure delayed Oops somewhere else. */
1430 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
1431 return _drbd_no_send_page(mdev, page, offset, size, msg_flags);
1433 msg_flags |= MSG_NOSIGNAL;
1434 drbd_update_congested(mdev->tconn);
1437 sent = mdev->tconn->data.socket->ops->sendpage(mdev->tconn->data.socket, page,
1440 if (sent == -EAGAIN) {
1441 if (we_should_drop_the_connection(mdev->tconn,
1442 mdev->tconn->data.socket))
1448 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
1449 __func__, (int)size, len, sent);
1454 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
1456 clear_bit(NET_CONGESTED, &mdev->tconn->flags);
1460 mdev->send_cnt += size>>9;
1464 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
1466 struct bio_vec *bvec;
1468 /* hint all but last page with MSG_MORE */
1469 __bio_for_each_segment(bvec, bio, i, 0) {
1470 if (!_drbd_no_send_page(mdev, bvec->bv_page,
1471 bvec->bv_offset, bvec->bv_len,
1472 i == bio->bi_vcnt -1 ? 0 : MSG_MORE))
1478 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
1480 struct bio_vec *bvec;
1482 /* hint all but last page with MSG_MORE */
1483 __bio_for_each_segment(bvec, bio, i, 0) {
1484 if (!_drbd_send_page(mdev, bvec->bv_page,
1485 bvec->bv_offset, bvec->bv_len,
1486 i == bio->bi_vcnt -1 ? 0 : MSG_MORE))
1492 static int _drbd_send_zc_ee(struct drbd_conf *mdev,
1493 struct drbd_peer_request *peer_req)
1495 struct page *page = peer_req->pages;
1496 unsigned len = peer_req->i.size;
1498 /* hint all but last page with MSG_MORE */
1499 page_chain_for_each(page) {
1500 unsigned l = min_t(unsigned, len, PAGE_SIZE);
1501 if (!_drbd_send_page(mdev, page, 0, l,
1502 page_chain_next(page) ? MSG_MORE : 0))
1509 static u32 bio_flags_to_wire(struct drbd_conf *mdev, unsigned long bi_rw)
1511 if (mdev->tconn->agreed_pro_version >= 95)
1512 return (bi_rw & REQ_SYNC ? DP_RW_SYNC : 0) |
1513 (bi_rw & REQ_FUA ? DP_FUA : 0) |
1514 (bi_rw & REQ_FLUSH ? DP_FLUSH : 0) |
1515 (bi_rw & REQ_DISCARD ? DP_DISCARD : 0);
1517 return bi_rw & REQ_SYNC ? DP_RW_SYNC : 0;
1520 /* Used to send write requests
1521 * R_PRIMARY -> Peer (P_DATA)
1523 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
1527 unsigned int dp_flags = 0;
1531 if (drbd_get_data_sock(mdev->tconn))
1534 dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_w_tfm) ?
1535 crypto_hash_digestsize(mdev->tconn->integrity_w_tfm) : 0;
1537 prepare_header(mdev, &p.head, P_DATA, sizeof(p) - sizeof(struct p_header) + dgs + req->i.size);
1538 p.sector = cpu_to_be64(req->i.sector);
1539 p.block_id = (unsigned long)req;
1540 p.seq_num = cpu_to_be32(req->seq_num = atomic_inc_return(&mdev->packet_seq));
1542 dp_flags = bio_flags_to_wire(mdev, req->master_bio->bi_rw);
1544 if (mdev->state.conn >= C_SYNC_SOURCE &&
1545 mdev->state.conn <= C_PAUSED_SYNC_T)
1546 dp_flags |= DP_MAY_SET_IN_SYNC;
1548 p.dp_flags = cpu_to_be32(dp_flags);
1549 set_bit(UNPLUG_REMOTE, &mdev->flags);
1551 drbd_send(mdev->tconn, mdev->tconn->data.socket, &p, sizeof(p), dgs ? MSG_MORE : 0));
1553 dgb = mdev->tconn->int_dig_out;
1554 drbd_csum_bio(mdev, mdev->tconn->integrity_w_tfm, req->master_bio, dgb);
1555 ok = dgs == drbd_send(mdev->tconn, mdev->tconn->data.socket, dgb, dgs, 0);
1558 /* For protocol A, we have to memcpy the payload into
1559 * socket buffers, as we may complete right away
1560 * as soon as we handed it over to tcp, at which point the data
1561 * pages may become invalid.
1563 * For data-integrity enabled, we copy it as well, so we can be
1564 * sure that even if the bio pages may still be modified, it
1565 * won't change the data on the wire, thus if the digest checks
1566 * out ok after sending on this side, but does not fit on the
1567 * receiving side, we sure have detected corruption elsewhere.
1569 if (mdev->tconn->net_conf->wire_protocol == DRBD_PROT_A || dgs)
1570 ok = _drbd_send_bio(mdev, req->master_bio);
1572 ok = _drbd_send_zc_bio(mdev, req->master_bio);
1574 /* double check digest, sometimes buffers have been modified in flight. */
1575 if (dgs > 0 && dgs <= 64) {
1576 /* 64 byte, 512 bit, is the largest digest size
1577 * currently supported in kernel crypto. */
1578 unsigned char digest[64];
1579 drbd_csum_bio(mdev, mdev->tconn->integrity_w_tfm, req->master_bio, digest);
1580 if (memcmp(mdev->tconn->int_dig_out, digest, dgs)) {
1582 "Digest mismatch, buffer modified by upper layers during write: %llus +%u\n",
1583 (unsigned long long)req->i.sector, req->i.size);
1585 } /* else if (dgs > 64) {
1586 ... Be noisy about digest too large ...
1590 drbd_put_data_sock(mdev->tconn);
1595 /* answer packet, used to send data back for read requests:
1596 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
1597 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
1599 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packet cmd,
1600 struct drbd_peer_request *peer_req)
1607 dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_w_tfm) ?
1608 crypto_hash_digestsize(mdev->tconn->integrity_w_tfm) : 0;
1610 prepare_header(mdev, &p.head, cmd, sizeof(p) -
1611 sizeof(struct p_header80) +
1612 dgs + peer_req->i.size);
1613 p.sector = cpu_to_be64(peer_req->i.sector);
1614 p.block_id = peer_req->block_id;
1615 p.seq_num = 0; /* unused */
1617 /* Only called by our kernel thread.
1618 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL
1619 * in response to admin command or module unload.
1621 if (drbd_get_data_sock(mdev->tconn))
1624 ok = sizeof(p) == drbd_send(mdev->tconn, mdev->tconn->data.socket, &p, sizeof(p), dgs ? MSG_MORE : 0);
1626 dgb = mdev->tconn->int_dig_out;
1627 drbd_csum_ee(mdev, mdev->tconn->integrity_w_tfm, peer_req, dgb);
1628 ok = dgs == drbd_send(mdev->tconn, mdev->tconn->data.socket, dgb, dgs, 0);
1631 ok = _drbd_send_zc_ee(mdev, peer_req);
1633 drbd_put_data_sock(mdev->tconn);
1638 int drbd_send_oos(struct drbd_conf *mdev, struct drbd_request *req)
1640 struct p_block_desc p;
1642 p.sector = cpu_to_be64(req->i.sector);
1643 p.blksize = cpu_to_be32(req->i.size);
1645 return !drbd_send_cmd(mdev, &mdev->tconn->data, P_OUT_OF_SYNC, &p.head, sizeof(p));
1649 drbd_send distinguishes two cases:
1651 Packets sent via the data socket "sock"
1652 and packets sent via the meta data socket "msock"
1655 -----------------+-------------------------+------------------------------
1656 timeout conf.timeout / 2 conf.timeout / 2
1657 timeout action send a ping via msock Abort communication
1658 and close all sockets
1662 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
1664 int drbd_send(struct drbd_tconn *tconn, struct socket *sock,
1665 void *buf, size_t size, unsigned msg_flags)
1674 /* THINK if (signal_pending) return ... ? */
1679 msg.msg_name = NULL;
1680 msg.msg_namelen = 0;
1681 msg.msg_control = NULL;
1682 msg.msg_controllen = 0;
1683 msg.msg_flags = msg_flags | MSG_NOSIGNAL;
1685 if (sock == tconn->data.socket) {
1686 tconn->ko_count = tconn->net_conf->ko_count;
1687 drbd_update_congested(tconn);
1691 * tcp_sendmsg does _not_ use its size parameter at all ?
1693 * -EAGAIN on timeout, -EINTR on signal.
1696 * do we need to block DRBD_SIG if sock == &meta.socket ??
1697 * otherwise wake_asender() might interrupt some send_*Ack !
1699 rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
1700 if (rv == -EAGAIN) {
1701 if (we_should_drop_the_connection(tconn, sock))
1707 flush_signals(current);
1715 } while (sent < size);
1717 if (sock == tconn->data.socket)
1718 clear_bit(NET_CONGESTED, &tconn->flags);
1721 if (rv != -EAGAIN) {
1722 conn_err(tconn, "%s_sendmsg returned %d\n",
1723 sock == tconn->meta.socket ? "msock" : "sock",
1725 conn_request_state(tconn, NS(conn, C_BROKEN_PIPE), CS_HARD);
1727 conn_request_state(tconn, NS(conn, C_TIMEOUT), CS_HARD);
1734 * drbd_send_all - Send an entire buffer
1736 * Returns 0 upon success and a negative error value otherwise.
1738 int drbd_send_all(struct drbd_tconn *tconn, struct socket *sock, void *buffer,
1739 size_t size, unsigned msg_flags)
1743 err = drbd_send(tconn, sock, buffer, size, msg_flags);
1751 static int drbd_open(struct block_device *bdev, fmode_t mode)
1753 struct drbd_conf *mdev = bdev->bd_disk->private_data;
1754 unsigned long flags;
1757 mutex_lock(&drbd_main_mutex);
1758 spin_lock_irqsave(&mdev->tconn->req_lock, flags);
1759 /* to have a stable mdev->state.role
1760 * and no race with updating open_cnt */
1762 if (mdev->state.role != R_PRIMARY) {
1763 if (mode & FMODE_WRITE)
1765 else if (!allow_oos)
1771 spin_unlock_irqrestore(&mdev->tconn->req_lock, flags);
1772 mutex_unlock(&drbd_main_mutex);
1777 static int drbd_release(struct gendisk *gd, fmode_t mode)
1779 struct drbd_conf *mdev = gd->private_data;
1780 mutex_lock(&drbd_main_mutex);
1782 mutex_unlock(&drbd_main_mutex);
1786 static void drbd_set_defaults(struct drbd_conf *mdev)
1788 /* Beware! The actual layout differs
1789 * between big endian and little endian */
1790 mdev->state = (union drbd_state) {
1791 { .role = R_SECONDARY,
1793 .conn = C_STANDALONE,
1802 void drbd_init_set_defaults(struct drbd_conf *mdev)
1804 /* the memset(,0,) did most of this.
1805 * note: only assignments, no allocation in here */
1807 drbd_set_defaults(mdev);
1809 atomic_set(&mdev->ap_bio_cnt, 0);
1810 atomic_set(&mdev->ap_pending_cnt, 0);
1811 atomic_set(&mdev->rs_pending_cnt, 0);
1812 atomic_set(&mdev->unacked_cnt, 0);
1813 atomic_set(&mdev->local_cnt, 0);
1814 atomic_set(&mdev->pp_in_use, 0);
1815 atomic_set(&mdev->pp_in_use_by_net, 0);
1816 atomic_set(&mdev->rs_sect_in, 0);
1817 atomic_set(&mdev->rs_sect_ev, 0);
1818 atomic_set(&mdev->ap_in_flight, 0);
1820 mutex_init(&mdev->md_io_mutex);
1821 mutex_init(&mdev->own_state_mutex);
1822 mdev->state_mutex = &mdev->own_state_mutex;
1824 spin_lock_init(&mdev->al_lock);
1825 spin_lock_init(&mdev->peer_seq_lock);
1826 spin_lock_init(&mdev->epoch_lock);
1828 INIT_LIST_HEAD(&mdev->active_ee);
1829 INIT_LIST_HEAD(&mdev->sync_ee);
1830 INIT_LIST_HEAD(&mdev->done_ee);
1831 INIT_LIST_HEAD(&mdev->read_ee);
1832 INIT_LIST_HEAD(&mdev->net_ee);
1833 INIT_LIST_HEAD(&mdev->resync_reads);
1834 INIT_LIST_HEAD(&mdev->resync_work.list);
1835 INIT_LIST_HEAD(&mdev->unplug_work.list);
1836 INIT_LIST_HEAD(&mdev->go_diskless.list);
1837 INIT_LIST_HEAD(&mdev->md_sync_work.list);
1838 INIT_LIST_HEAD(&mdev->start_resync_work.list);
1839 INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
1841 mdev->resync_work.cb = w_resync_timer;
1842 mdev->unplug_work.cb = w_send_write_hint;
1843 mdev->go_diskless.cb = w_go_diskless;
1844 mdev->md_sync_work.cb = w_md_sync;
1845 mdev->bm_io_work.w.cb = w_bitmap_io;
1846 mdev->start_resync_work.cb = w_start_resync;
1848 mdev->resync_work.mdev = mdev;
1849 mdev->unplug_work.mdev = mdev;
1850 mdev->go_diskless.mdev = mdev;
1851 mdev->md_sync_work.mdev = mdev;
1852 mdev->bm_io_work.w.mdev = mdev;
1853 mdev->start_resync_work.mdev = mdev;
1855 init_timer(&mdev->resync_timer);
1856 init_timer(&mdev->md_sync_timer);
1857 init_timer(&mdev->start_resync_timer);
1858 init_timer(&mdev->request_timer);
1859 mdev->resync_timer.function = resync_timer_fn;
1860 mdev->resync_timer.data = (unsigned long) mdev;
1861 mdev->md_sync_timer.function = md_sync_timer_fn;
1862 mdev->md_sync_timer.data = (unsigned long) mdev;
1863 mdev->start_resync_timer.function = start_resync_timer_fn;
1864 mdev->start_resync_timer.data = (unsigned long) mdev;
1865 mdev->request_timer.function = request_timer_fn;
1866 mdev->request_timer.data = (unsigned long) mdev;
1868 init_waitqueue_head(&mdev->misc_wait);
1869 init_waitqueue_head(&mdev->state_wait);
1870 init_waitqueue_head(&mdev->ee_wait);
1871 init_waitqueue_head(&mdev->al_wait);
1872 init_waitqueue_head(&mdev->seq_wait);
1874 /* mdev->tconn->agreed_pro_version gets initialized in drbd_connect() */
1875 mdev->write_ordering = WO_bdev_flush;
1876 mdev->resync_wenr = LC_FREE;
1877 mdev->peer_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
1878 mdev->local_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
1881 void drbd_mdev_cleanup(struct drbd_conf *mdev)
1884 if (mdev->tconn->receiver.t_state != NONE)
1885 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
1886 mdev->tconn->receiver.t_state);
1888 /* no need to lock it, I'm the only thread alive */
1889 if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
1890 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
1900 mdev->rs_failed = 0;
1901 mdev->rs_last_events = 0;
1902 mdev->rs_last_sect_ev = 0;
1903 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
1904 mdev->rs_mark_left[i] = 0;
1905 mdev->rs_mark_time[i] = 0;
1907 D_ASSERT(mdev->tconn->net_conf == NULL);
1909 drbd_set_my_capacity(mdev, 0);
1911 /* maybe never allocated. */
1912 drbd_bm_resize(mdev, 0, 1);
1913 drbd_bm_cleanup(mdev);
1916 drbd_free_resources(mdev);
1917 clear_bit(AL_SUSPENDED, &mdev->flags);
1920 * currently we drbd_init_ee only on module load, so
1921 * we may do drbd_release_ee only on module unload!
1923 D_ASSERT(list_empty(&mdev->active_ee));
1924 D_ASSERT(list_empty(&mdev->sync_ee));
1925 D_ASSERT(list_empty(&mdev->done_ee));
1926 D_ASSERT(list_empty(&mdev->read_ee));
1927 D_ASSERT(list_empty(&mdev->net_ee));
1928 D_ASSERT(list_empty(&mdev->resync_reads));
1929 D_ASSERT(list_empty(&mdev->tconn->data.work.q));
1930 D_ASSERT(list_empty(&mdev->tconn->meta.work.q));
1931 D_ASSERT(list_empty(&mdev->resync_work.list));
1932 D_ASSERT(list_empty(&mdev->unplug_work.list));
1933 D_ASSERT(list_empty(&mdev->go_diskless.list));
1935 drbd_set_defaults(mdev);
1939 static void drbd_destroy_mempools(void)
1943 while (drbd_pp_pool) {
1944 page = drbd_pp_pool;
1945 drbd_pp_pool = (struct page *)page_private(page);
1950 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
1952 if (drbd_md_io_bio_set)
1953 bioset_free(drbd_md_io_bio_set);
1954 if (drbd_md_io_page_pool)
1955 mempool_destroy(drbd_md_io_page_pool);
1956 if (drbd_ee_mempool)
1957 mempool_destroy(drbd_ee_mempool);
1958 if (drbd_request_mempool)
1959 mempool_destroy(drbd_request_mempool);
1961 kmem_cache_destroy(drbd_ee_cache);
1962 if (drbd_request_cache)
1963 kmem_cache_destroy(drbd_request_cache);
1964 if (drbd_bm_ext_cache)
1965 kmem_cache_destroy(drbd_bm_ext_cache);
1966 if (drbd_al_ext_cache)
1967 kmem_cache_destroy(drbd_al_ext_cache);
1969 drbd_md_io_bio_set = NULL;
1970 drbd_md_io_page_pool = NULL;
1971 drbd_ee_mempool = NULL;
1972 drbd_request_mempool = NULL;
1973 drbd_ee_cache = NULL;
1974 drbd_request_cache = NULL;
1975 drbd_bm_ext_cache = NULL;
1976 drbd_al_ext_cache = NULL;
1981 static int drbd_create_mempools(void)
1984 const int number = (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count;
1987 /* prepare our caches and mempools */
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;
1993 drbd_pp_pool = NULL;
1994 drbd_md_io_page_pool = NULL;
1995 drbd_md_io_bio_set = NULL;
1998 drbd_request_cache = kmem_cache_create(
1999 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
2000 if (drbd_request_cache == NULL)
2003 drbd_ee_cache = kmem_cache_create(
2004 "drbd_ee", sizeof(struct drbd_peer_request), 0, 0, NULL);
2005 if (drbd_ee_cache == NULL)
2008 drbd_bm_ext_cache = kmem_cache_create(
2009 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
2010 if (drbd_bm_ext_cache == NULL)
2013 drbd_al_ext_cache = kmem_cache_create(
2014 "drbd_al", sizeof(struct lc_element), 0, 0, NULL);
2015 if (drbd_al_ext_cache == NULL)
2019 drbd_md_io_bio_set = bioset_create(DRBD_MIN_POOL_PAGES, 0);
2020 if (drbd_md_io_bio_set == NULL)
2023 drbd_md_io_page_pool = mempool_create_page_pool(DRBD_MIN_POOL_PAGES, 0);
2024 if (drbd_md_io_page_pool == NULL)
2027 drbd_request_mempool = mempool_create(number,
2028 mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
2029 if (drbd_request_mempool == NULL)
2032 drbd_ee_mempool = mempool_create(number,
2033 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2034 if (drbd_ee_mempool == NULL)
2037 /* drbd's page pool */
2038 spin_lock_init(&drbd_pp_lock);
2040 for (i = 0; i < number; i++) {
2041 page = alloc_page(GFP_HIGHUSER);
2044 set_page_private(page, (unsigned long)drbd_pp_pool);
2045 drbd_pp_pool = page;
2047 drbd_pp_vacant = number;
2052 drbd_destroy_mempools(); /* in case we allocated some */
2056 static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
2059 /* just so we have it. you never know what interesting things we
2060 * might want to do here some day...
2066 static struct notifier_block drbd_notifier = {
2067 .notifier_call = drbd_notify_sys,
2070 static void drbd_release_ee_lists(struct drbd_conf *mdev)
2074 rr = drbd_release_ee(mdev, &mdev->active_ee);
2076 dev_err(DEV, "%d EEs in active list found!\n", rr);
2078 rr = drbd_release_ee(mdev, &mdev->sync_ee);
2080 dev_err(DEV, "%d EEs in sync list found!\n", rr);
2082 rr = drbd_release_ee(mdev, &mdev->read_ee);
2084 dev_err(DEV, "%d EEs in read list found!\n", rr);
2086 rr = drbd_release_ee(mdev, &mdev->done_ee);
2088 dev_err(DEV, "%d EEs in done list found!\n", rr);
2090 rr = drbd_release_ee(mdev, &mdev->net_ee);
2092 dev_err(DEV, "%d EEs in net list found!\n", rr);
2095 /* caution. no locking. */
2096 void drbd_delete_device(unsigned int minor)
2098 struct drbd_conf *mdev = minor_to_mdev(minor);
2103 idr_remove(&mdev->tconn->volumes, mdev->vnr);
2104 idr_remove(&minors, minor);
2107 /* paranoia asserts */
2108 D_ASSERT(mdev->open_cnt == 0);
2109 D_ASSERT(list_empty(&mdev->tconn->data.work.q));
2110 /* end paranoia asserts */
2112 del_gendisk(mdev->vdisk);
2114 /* cleanup stuff that may have been allocated during
2115 * device (re-)configuration or state changes */
2117 if (mdev->this_bdev)
2118 bdput(mdev->this_bdev);
2120 drbd_free_resources(mdev);
2122 drbd_release_ee_lists(mdev);
2124 lc_destroy(mdev->act_log);
2125 lc_destroy(mdev->resync);
2127 kfree(mdev->p_uuid);
2128 /* mdev->p_uuid = NULL; */
2130 /* cleanup the rest that has been
2131 * allocated from drbd_new_device
2132 * and actually free the mdev itself */
2133 drbd_free_mdev(mdev);
2136 static void drbd_cleanup(void)
2139 struct drbd_conf *mdev;
2141 unregister_reboot_notifier(&drbd_notifier);
2143 /* first remove proc,
2144 * drbdsetup uses it's presence to detect
2145 * whether DRBD is loaded.
2146 * If we would get stuck in proc removal,
2147 * but have netlink already deregistered,
2148 * some drbdsetup commands may wait forever
2152 remove_proc_entry("drbd", NULL);
2154 drbd_genl_unregister();
2156 idr_for_each_entry(&minors, mdev, i)
2157 drbd_delete_device(i);
2158 drbd_destroy_mempools();
2159 unregister_blkdev(DRBD_MAJOR, "drbd");
2161 idr_destroy(&minors);
2163 printk(KERN_INFO "drbd: module cleanup done.\n");
2167 * drbd_congested() - Callback for pdflush
2168 * @congested_data: User data
2169 * @bdi_bits: Bits pdflush is currently interested in
2171 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
2173 static int drbd_congested(void *congested_data, int bdi_bits)
2175 struct drbd_conf *mdev = congested_data;
2176 struct request_queue *q;
2180 if (!may_inc_ap_bio(mdev)) {
2181 /* DRBD has frozen IO */
2187 if (get_ldev(mdev)) {
2188 q = bdev_get_queue(mdev->ldev->backing_bdev);
2189 r = bdi_congested(&q->backing_dev_info, bdi_bits);
2195 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->tconn->flags)) {
2196 r |= (1 << BDI_async_congested);
2197 reason = reason == 'b' ? 'a' : 'n';
2201 mdev->congestion_reason = reason;
2205 static void drbd_init_workqueue(struct drbd_work_queue* wq)
2207 sema_init(&wq->s, 0);
2208 spin_lock_init(&wq->q_lock);
2209 INIT_LIST_HEAD(&wq->q);
2212 struct drbd_tconn *conn_by_name(const char *name)
2214 struct drbd_tconn *tconn;
2216 if (!name || !name[0])
2219 mutex_lock(&drbd_cfg_mutex);
2220 list_for_each_entry(tconn, &drbd_tconns, all_tconn) {
2221 if (!strcmp(tconn->name, name))
2226 mutex_unlock(&drbd_cfg_mutex);
2230 struct drbd_tconn *drbd_new_tconn(const char *name)
2232 struct drbd_tconn *tconn;
2234 tconn = kzalloc(sizeof(struct drbd_tconn), GFP_KERNEL);
2238 tconn->name = kstrdup(name, GFP_KERNEL);
2242 if (!zalloc_cpumask_var(&tconn->cpu_mask, GFP_KERNEL))
2245 if (!tl_init(tconn))
2248 tconn->cstate = C_STANDALONE;
2249 mutex_init(&tconn->cstate_mutex);
2250 spin_lock_init(&tconn->req_lock);
2251 atomic_set(&tconn->net_cnt, 0);
2252 init_waitqueue_head(&tconn->net_cnt_wait);
2253 init_waitqueue_head(&tconn->ping_wait);
2254 idr_init(&tconn->volumes);
2256 drbd_init_workqueue(&tconn->data.work);
2257 mutex_init(&tconn->data.mutex);
2259 drbd_init_workqueue(&tconn->meta.work);
2260 mutex_init(&tconn->meta.mutex);
2262 drbd_thread_init(tconn, &tconn->receiver, drbdd_init, "receiver");
2263 drbd_thread_init(tconn, &tconn->worker, drbd_worker, "worker");
2264 drbd_thread_init(tconn, &tconn->asender, drbd_asender, "asender");
2266 tconn->res_opts = (struct res_opts) {
2267 {}, 0, /* cpu_mask */
2268 DRBD_ON_NO_DATA_DEF, /* on_no_data */
2271 mutex_lock(&drbd_cfg_mutex);
2272 list_add_tail(&tconn->all_tconn, &drbd_tconns);
2273 mutex_unlock(&drbd_cfg_mutex);
2279 free_cpumask_var(tconn->cpu_mask);
2286 void drbd_free_tconn(struct drbd_tconn *tconn)
2288 list_del(&tconn->all_tconn);
2289 idr_destroy(&tconn->volumes);
2291 free_cpumask_var(tconn->cpu_mask);
2293 kfree(tconn->int_dig_out);
2294 kfree(tconn->int_dig_in);
2295 kfree(tconn->int_dig_vv);
2299 enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor, int vnr)
2301 struct drbd_conf *mdev;
2302 struct gendisk *disk;
2303 struct request_queue *q;
2305 int minor_got = minor;
2306 enum drbd_ret_code err = ERR_NOMEM;
2308 mdev = minor_to_mdev(minor);
2310 return ERR_MINOR_EXISTS;
2312 /* GFP_KERNEL, we are outside of all write-out paths */
2313 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
2317 mdev->tconn = tconn;
2318 mdev->minor = minor;
2321 drbd_init_set_defaults(mdev);
2323 q = blk_alloc_queue(GFP_KERNEL);
2327 q->queuedata = mdev;
2329 disk = alloc_disk(1);
2334 set_disk_ro(disk, true);
2337 disk->major = DRBD_MAJOR;
2338 disk->first_minor = minor;
2339 disk->fops = &drbd_ops;
2340 sprintf(disk->disk_name, "drbd%d", minor);
2341 disk->private_data = mdev;
2343 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
2344 /* we have no partitions. we contain only ourselves. */
2345 mdev->this_bdev->bd_contains = mdev->this_bdev;
2347 q->backing_dev_info.congested_fn = drbd_congested;
2348 q->backing_dev_info.congested_data = mdev;
2350 blk_queue_make_request(q, drbd_make_request);
2351 /* Setting the max_hw_sectors to an odd value of 8kibyte here
2352 This triggers a max_bio_size message upon first attach or connect */
2353 blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8);
2354 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
2355 blk_queue_merge_bvec(q, drbd_merge_bvec);
2356 q->queue_lock = &mdev->tconn->req_lock; /* needed since we use */
2358 mdev->md_io_page = alloc_page(GFP_KERNEL);
2359 if (!mdev->md_io_page)
2360 goto out_no_io_page;
2362 if (drbd_bm_init(mdev))
2364 mdev->read_requests = RB_ROOT;
2365 mdev->write_requests = RB_ROOT;
2367 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
2368 if (!mdev->current_epoch)
2371 INIT_LIST_HEAD(&mdev->current_epoch->list);
2374 if (!idr_pre_get(&minors, GFP_KERNEL))
2375 goto out_no_minor_idr;
2376 if (idr_get_new_above(&minors, mdev, minor, &minor_got))
2377 goto out_no_minor_idr;
2378 if (minor_got != minor) {
2379 err = ERR_MINOR_EXISTS;
2380 drbd_msg_put_info("requested minor exists already");
2381 goto out_idr_remove_minor;
2384 if (!idr_pre_get(&tconn->volumes, GFP_KERNEL))
2385 goto out_idr_remove_minor;
2386 if (idr_get_new_above(&tconn->volumes, mdev, vnr, &vnr_got))
2387 goto out_idr_remove_minor;
2388 if (vnr_got != vnr) {
2389 err = ERR_INVALID_REQUEST;
2390 drbd_msg_put_info("requested volume exists already");
2391 goto out_idr_remove_vol;
2395 /* inherit the connection state */
2396 mdev->state.conn = tconn->cstate;
2397 if (mdev->state.conn == C_WF_REPORT_PARAMS)
2398 drbd_connected(vnr, mdev, tconn);
2403 idr_remove(&tconn->volumes, vnr_got);
2404 out_idr_remove_minor:
2405 idr_remove(&minors, minor_got);
2408 kfree(mdev->current_epoch);
2410 drbd_bm_cleanup(mdev);
2412 __free_page(mdev->md_io_page);
2416 blk_cleanup_queue(q);
2422 /* counterpart of drbd_new_device.
2423 * last part of drbd_delete_device. */
2424 void drbd_free_mdev(struct drbd_conf *mdev)
2426 kfree(mdev->current_epoch);
2427 if (mdev->bitmap) /* should no longer be there. */
2428 drbd_bm_cleanup(mdev);
2429 __free_page(mdev->md_io_page);
2430 put_disk(mdev->vdisk);
2431 blk_cleanup_queue(mdev->rq_queue);
2436 int __init drbd_init(void)
2440 BUILD_BUG_ON(sizeof(struct p_header80) != sizeof(struct p_header95));
2441 BUILD_BUG_ON(sizeof(struct p_handshake) != 80);
2443 if (minor_count < DRBD_MINOR_COUNT_MIN || minor_count > DRBD_MINOR_COUNT_MAX) {
2445 "drbd: invalid minor_count (%d)\n", minor_count);
2453 err = register_blkdev(DRBD_MAJOR, "drbd");
2456 "drbd: unable to register block device major %d\n",
2461 err = drbd_genl_register();
2463 printk(KERN_ERR "drbd: unable to register generic netlink family\n");
2468 register_reboot_notifier(&drbd_notifier);
2471 * allocate all necessary structs
2475 init_waitqueue_head(&drbd_pp_wait);
2477 drbd_proc = NULL; /* play safe for drbd_cleanup */
2480 err = drbd_create_mempools();
2484 drbd_proc = proc_create_data("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops, NULL);
2486 printk(KERN_ERR "drbd: unable to register proc file\n");
2490 rwlock_init(&global_state_lock);
2491 INIT_LIST_HEAD(&drbd_tconns);
2493 printk(KERN_INFO "drbd: initialized. "
2494 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
2495 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
2496 printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
2497 printk(KERN_INFO "drbd: registered as block device major %d\n",
2500 return 0; /* Success! */
2505 /* currently always the case */
2506 printk(KERN_ERR "drbd: ran out of memory\n");
2508 printk(KERN_ERR "drbd: initialization failure\n");
2512 void drbd_free_bc(struct drbd_backing_dev *ldev)
2517 blkdev_put(ldev->backing_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
2518 blkdev_put(ldev->md_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
2523 void drbd_free_sock(struct drbd_tconn *tconn)
2525 if (tconn->data.socket) {
2526 mutex_lock(&tconn->data.mutex);
2527 kernel_sock_shutdown(tconn->data.socket, SHUT_RDWR);
2528 sock_release(tconn->data.socket);
2529 tconn->data.socket = NULL;
2530 mutex_unlock(&tconn->data.mutex);
2532 if (tconn->meta.socket) {
2533 mutex_lock(&tconn->meta.mutex);
2534 kernel_sock_shutdown(tconn->meta.socket, SHUT_RDWR);
2535 sock_release(tconn->meta.socket);
2536 tconn->meta.socket = NULL;
2537 mutex_unlock(&tconn->meta.mutex);
2542 void drbd_free_resources(struct drbd_conf *mdev)
2544 crypto_free_hash(mdev->tconn->csums_tfm);
2545 mdev->tconn->csums_tfm = NULL;
2546 crypto_free_hash(mdev->tconn->verify_tfm);
2547 mdev->tconn->verify_tfm = NULL;
2548 crypto_free_hash(mdev->tconn->cram_hmac_tfm);
2549 mdev->tconn->cram_hmac_tfm = NULL;
2550 crypto_free_hash(mdev->tconn->integrity_w_tfm);
2551 mdev->tconn->integrity_w_tfm = NULL;
2552 crypto_free_hash(mdev->tconn->integrity_r_tfm);
2553 mdev->tconn->integrity_r_tfm = NULL;
2555 drbd_free_sock(mdev->tconn);
2558 drbd_free_bc(mdev->ldev);
2559 mdev->ldev = NULL;);
2562 /* meta data management */
2564 struct meta_data_on_disk {
2565 u64 la_size; /* last agreed size. */
2566 u64 uuid[UI_SIZE]; /* UUIDs. */
2569 u32 flags; /* MDF */
2572 u32 al_offset; /* offset to this block */
2573 u32 al_nr_extents; /* important for restoring the AL */
2574 /* `-- act_log->nr_elements <-- ldev->dc.al_extents */
2575 u32 bm_offset; /* offset to the bitmap, from here */
2576 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
2577 u32 la_peer_max_bio_size; /* last peer max_bio_size */
2578 u32 reserved_u32[3];
2583 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
2584 * @mdev: DRBD device.
2586 void drbd_md_sync(struct drbd_conf *mdev)
2588 struct meta_data_on_disk *buffer;
2592 del_timer(&mdev->md_sync_timer);
2593 /* timer may be rearmed by drbd_md_mark_dirty() now. */
2594 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
2597 /* We use here D_FAILED and not D_ATTACHING because we try to write
2598 * metadata even if we detach due to a disk failure! */
2599 if (!get_ldev_if_state(mdev, D_FAILED))
2602 mutex_lock(&mdev->md_io_mutex);
2603 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
2604 memset(buffer, 0, 512);
2606 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
2607 for (i = UI_CURRENT; i < UI_SIZE; i++)
2608 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
2609 buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
2610 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
2612 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
2613 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
2614 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
2615 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
2616 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
2618 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
2619 buffer->la_peer_max_bio_size = cpu_to_be32(mdev->peer_max_bio_size);
2621 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
2622 sector = mdev->ldev->md.md_offset;
2624 if (!drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
2625 /* this was a try anyways ... */
2626 dev_err(DEV, "meta data update failed!\n");
2627 drbd_chk_io_error(mdev, 1, true);
2630 /* Update mdev->ldev->md.la_size_sect,
2631 * since we updated it on metadata. */
2632 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
2634 mutex_unlock(&mdev->md_io_mutex);
2639 * drbd_md_read() - Reads in the meta data super block
2640 * @mdev: DRBD device.
2641 * @bdev: Device from which the meta data should be read in.
2643 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_code in case
2644 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
2646 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
2648 struct meta_data_on_disk *buffer;
2649 int i, rv = NO_ERROR;
2651 if (!get_ldev_if_state(mdev, D_ATTACHING))
2652 return ERR_IO_MD_DISK;
2654 mutex_lock(&mdev->md_io_mutex);
2655 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
2657 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
2658 /* NOTE: can't do normal error processing here as this is
2659 called BEFORE disk is attached */
2660 dev_err(DEV, "Error while reading metadata.\n");
2661 rv = ERR_IO_MD_DISK;
2665 if (buffer->magic != cpu_to_be32(DRBD_MD_MAGIC)) {
2666 dev_err(DEV, "Error while reading metadata, magic not found.\n");
2667 rv = ERR_MD_INVALID;
2670 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
2671 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
2672 be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
2673 rv = ERR_MD_INVALID;
2676 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
2677 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
2678 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
2679 rv = ERR_MD_INVALID;
2682 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
2683 dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
2684 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
2685 rv = ERR_MD_INVALID;
2689 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
2690 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
2691 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
2692 rv = ERR_MD_INVALID;
2696 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
2697 for (i = UI_CURRENT; i < UI_SIZE; i++)
2698 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
2699 bdev->md.flags = be32_to_cpu(buffer->flags);
2700 bdev->dc.al_extents = be32_to_cpu(buffer->al_nr_extents);
2701 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
2703 spin_lock_irq(&mdev->tconn->req_lock);
2704 if (mdev->state.conn < C_CONNECTED) {
2706 peer = be32_to_cpu(buffer->la_peer_max_bio_size);
2707 peer = max_t(int, peer, DRBD_MAX_BIO_SIZE_SAFE);
2708 mdev->peer_max_bio_size = peer;
2710 spin_unlock_irq(&mdev->tconn->req_lock);
2712 if (bdev->dc.al_extents < 7)
2713 bdev->dc.al_extents = 127;
2716 mutex_unlock(&mdev->md_io_mutex);
2723 * drbd_md_mark_dirty() - Mark meta data super block as dirty
2724 * @mdev: DRBD device.
2726 * Call this function if you change anything that should be written to
2727 * the meta-data super block. This function sets MD_DIRTY, and starts a
2728 * timer that ensures that within five seconds you have to call drbd_md_sync().
2731 void drbd_md_mark_dirty_(struct drbd_conf *mdev, unsigned int line, const char *func)
2733 if (!test_and_set_bit(MD_DIRTY, &mdev->flags)) {
2734 mod_timer(&mdev->md_sync_timer, jiffies + HZ);
2735 mdev->last_md_mark_dirty.line = line;
2736 mdev->last_md_mark_dirty.func = func;
2740 void drbd_md_mark_dirty(struct drbd_conf *mdev)
2742 if (!test_and_set_bit(MD_DIRTY, &mdev->flags))
2743 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
2747 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
2751 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
2752 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
2755 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
2757 if (idx == UI_CURRENT) {
2758 if (mdev->state.role == R_PRIMARY)
2763 drbd_set_ed_uuid(mdev, val);
2766 mdev->ldev->md.uuid[idx] = val;
2767 drbd_md_mark_dirty(mdev);
2771 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
2773 if (mdev->ldev->md.uuid[idx]) {
2774 drbd_uuid_move_history(mdev);
2775 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
2777 _drbd_uuid_set(mdev, idx, val);
2781 * drbd_uuid_new_current() - Creates a new current UUID
2782 * @mdev: DRBD device.
2784 * Creates a new current UUID, and rotates the old current UUID into
2785 * the bitmap slot. Causes an incremental resync upon next connect.
2787 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
2790 unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];
2793 dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
2795 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
2797 get_random_bytes(&val, sizeof(u64));
2798 _drbd_uuid_set(mdev, UI_CURRENT, val);
2799 drbd_print_uuids(mdev, "new current UUID");
2800 /* get it to stable storage _now_ */
2804 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
2806 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
2810 drbd_uuid_move_history(mdev);
2811 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
2812 mdev->ldev->md.uuid[UI_BITMAP] = 0;
2814 unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];
2816 dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
2818 mdev->ldev->md.uuid[UI_BITMAP] = val & ~((u64)1);
2820 drbd_md_mark_dirty(mdev);
2824 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
2825 * @mdev: DRBD device.
2827 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
2829 int drbd_bmio_set_n_write(struct drbd_conf *mdev)
2833 if (get_ldev_if_state(mdev, D_ATTACHING)) {
2834 drbd_md_set_flag(mdev, MDF_FULL_SYNC);
2836 drbd_bm_set_all(mdev);
2838 rv = drbd_bm_write(mdev);
2841 drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
2852 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
2853 * @mdev: DRBD device.
2855 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
2857 int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
2861 drbd_resume_al(mdev);
2862 if (get_ldev_if_state(mdev, D_ATTACHING)) {
2863 drbd_bm_clear_all(mdev);
2864 rv = drbd_bm_write(mdev);
2871 static int w_bitmap_io(struct drbd_work *w, int unused)
2873 struct bm_io_work *work = container_of(w, struct bm_io_work, w);
2874 struct drbd_conf *mdev = w->mdev;
2877 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
2879 if (get_ldev(mdev)) {
2880 drbd_bm_lock(mdev, work->why, work->flags);
2881 rv = work->io_fn(mdev);
2882 drbd_bm_unlock(mdev);
2886 clear_bit_unlock(BITMAP_IO, &mdev->flags);
2887 wake_up(&mdev->misc_wait);
2890 work->done(mdev, rv);
2892 clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
2899 void drbd_ldev_destroy(struct drbd_conf *mdev)
2901 lc_destroy(mdev->resync);
2902 mdev->resync = NULL;
2903 lc_destroy(mdev->act_log);
2904 mdev->act_log = NULL;
2906 drbd_free_bc(mdev->ldev);
2907 mdev->ldev = NULL;);
2909 clear_bit(GO_DISKLESS, &mdev->flags);
2912 static int w_go_diskless(struct drbd_work *w, int unused)
2914 struct drbd_conf *mdev = w->mdev;
2916 D_ASSERT(mdev->state.disk == D_FAILED);
2917 /* we cannot assert local_cnt == 0 here, as get_ldev_if_state will
2918 * inc/dec it frequently. Once we are D_DISKLESS, no one will touch
2919 * the protected members anymore, though, so once put_ldev reaches zero
2920 * again, it will be safe to free them. */
2921 drbd_force_state(mdev, NS(disk, D_DISKLESS));
2925 void drbd_go_diskless(struct drbd_conf *mdev)
2927 D_ASSERT(mdev->state.disk == D_FAILED);
2928 if (!test_and_set_bit(GO_DISKLESS, &mdev->flags))
2929 drbd_queue_work(&mdev->tconn->data.work, &mdev->go_diskless);
2933 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
2934 * @mdev: DRBD device.
2935 * @io_fn: IO callback to be called when bitmap IO is possible
2936 * @done: callback to be called after the bitmap IO was performed
2937 * @why: Descriptive text of the reason for doing the IO
2939 * While IO on the bitmap happens we freeze application IO thus we ensure
2940 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
2941 * called from worker context. It MUST NOT be used while a previous such
2942 * work is still pending!
2944 void drbd_queue_bitmap_io(struct drbd_conf *mdev,
2945 int (*io_fn)(struct drbd_conf *),
2946 void (*done)(struct drbd_conf *, int),
2947 char *why, enum bm_flag flags)
2949 D_ASSERT(current == mdev->tconn->worker.task);
2951 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
2952 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
2953 D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
2954 if (mdev->bm_io_work.why)
2955 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
2956 why, mdev->bm_io_work.why);
2958 mdev->bm_io_work.io_fn = io_fn;
2959 mdev->bm_io_work.done = done;
2960 mdev->bm_io_work.why = why;
2961 mdev->bm_io_work.flags = flags;
2963 spin_lock_irq(&mdev->tconn->req_lock);
2964 set_bit(BITMAP_IO, &mdev->flags);
2965 if (atomic_read(&mdev->ap_bio_cnt) == 0) {
2966 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
2967 drbd_queue_work(&mdev->tconn->data.work, &mdev->bm_io_work.w);
2969 spin_unlock_irq(&mdev->tconn->req_lock);
2973 * drbd_bitmap_io() - Does an IO operation on the whole bitmap
2974 * @mdev: DRBD device.
2975 * @io_fn: IO callback to be called when bitmap IO is possible
2976 * @why: Descriptive text of the reason for doing the IO
2978 * freezes application IO while that the actual IO operations runs. This
2979 * functions MAY NOT be called from worker context.
2981 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *),
2982 char *why, enum bm_flag flags)
2986 D_ASSERT(current != mdev->tconn->worker.task);
2988 if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
2989 drbd_suspend_io(mdev);
2991 drbd_bm_lock(mdev, why, flags);
2993 drbd_bm_unlock(mdev);
2995 if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
2996 drbd_resume_io(mdev);
3001 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3003 if ((mdev->ldev->md.flags & flag) != flag) {
3004 drbd_md_mark_dirty(mdev);
3005 mdev->ldev->md.flags |= flag;
3009 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
3011 if ((mdev->ldev->md.flags & flag) != 0) {
3012 drbd_md_mark_dirty(mdev);
3013 mdev->ldev->md.flags &= ~flag;
3016 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
3018 return (bdev->md.flags & flag) != 0;
3021 static void md_sync_timer_fn(unsigned long data)
3023 struct drbd_conf *mdev = (struct drbd_conf *) data;
3025 drbd_queue_work_front(&mdev->tconn->data.work, &mdev->md_sync_work);
3028 static int w_md_sync(struct drbd_work *w, int unused)
3030 struct drbd_conf *mdev = w->mdev;
3032 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3034 dev_warn(DEV, "last md_mark_dirty: %s:%u\n",
3035 mdev->last_md_mark_dirty.func, mdev->last_md_mark_dirty.line);
3041 const char *cmdname(enum drbd_packet cmd)
3043 /* THINK may need to become several global tables
3044 * when we want to support more than
3045 * one PRO_VERSION */
3046 static const char *cmdnames[] = {
3048 [P_DATA_REPLY] = "DataReply",
3049 [P_RS_DATA_REPLY] = "RSDataReply",
3050 [P_BARRIER] = "Barrier",
3051 [P_BITMAP] = "ReportBitMap",
3052 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget",
3053 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource",
3054 [P_UNPLUG_REMOTE] = "UnplugRemote",
3055 [P_DATA_REQUEST] = "DataRequest",
3056 [P_RS_DATA_REQUEST] = "RSDataRequest",
3057 [P_SYNC_PARAM] = "SyncParam",
3058 [P_SYNC_PARAM89] = "SyncParam89",
3059 [P_PROTOCOL] = "ReportProtocol",
3060 [P_UUIDS] = "ReportUUIDs",
3061 [P_SIZES] = "ReportSizes",
3062 [P_STATE] = "ReportState",
3063 [P_SYNC_UUID] = "ReportSyncUUID",
3064 [P_AUTH_CHALLENGE] = "AuthChallenge",
3065 [P_AUTH_RESPONSE] = "AuthResponse",
3067 [P_PING_ACK] = "PingAck",
3068 [P_RECV_ACK] = "RecvAck",
3069 [P_WRITE_ACK] = "WriteAck",
3070 [P_RS_WRITE_ACK] = "RSWriteAck",
3071 [P_DISCARD_WRITE] = "DiscardWrite",
3072 [P_NEG_ACK] = "NegAck",
3073 [P_NEG_DREPLY] = "NegDReply",
3074 [P_NEG_RS_DREPLY] = "NegRSDReply",
3075 [P_BARRIER_ACK] = "BarrierAck",
3076 [P_STATE_CHG_REQ] = "StateChgRequest",
3077 [P_STATE_CHG_REPLY] = "StateChgReply",
3078 [P_OV_REQUEST] = "OVRequest",
3079 [P_OV_REPLY] = "OVReply",
3080 [P_OV_RESULT] = "OVResult",
3081 [P_CSUM_RS_REQUEST] = "CsumRSRequest",
3082 [P_RS_IS_IN_SYNC] = "CsumRSIsInSync",
3083 [P_COMPRESSED_BITMAP] = "CBitmap",
3084 [P_DELAY_PROBE] = "DelayProbe",
3085 [P_OUT_OF_SYNC] = "OutOfSync",
3086 [P_RETRY_WRITE] = "RetryWrite",
3089 if (cmd == P_HAND_SHAKE_M)
3090 return "HandShakeM";
3091 if (cmd == P_HAND_SHAKE_S)
3092 return "HandShakeS";
3093 if (cmd == P_HAND_SHAKE)
3095 if (cmd >= ARRAY_SIZE(cmdnames))
3097 return cmdnames[cmd];
3101 * drbd_wait_misc - wait for a request to make progress
3102 * @mdev: device associated with the request
3103 * @i: the struct drbd_interval embedded in struct drbd_request or
3104 * struct drbd_peer_request
3106 int drbd_wait_misc(struct drbd_conf *mdev, struct drbd_interval *i)
3108 struct net_conf *net_conf = mdev->tconn->net_conf;
3114 timeout = MAX_SCHEDULE_TIMEOUT;
3115 if (net_conf->ko_count)
3116 timeout = net_conf->timeout * HZ / 10 * net_conf->ko_count;
3118 /* Indicate to wake up mdev->misc_wait on progress. */
3120 prepare_to_wait(&mdev->misc_wait, &wait, TASK_INTERRUPTIBLE);
3121 spin_unlock_irq(&mdev->tconn->req_lock);
3122 timeout = schedule_timeout(timeout);
3123 finish_wait(&mdev->misc_wait, &wait);
3124 spin_lock_irq(&mdev->tconn->req_lock);
3125 if (!timeout || mdev->state.conn < C_CONNECTED)
3127 if (signal_pending(current))
3128 return -ERESTARTSYS;
3132 #ifdef CONFIG_DRBD_FAULT_INJECTION
3133 /* Fault insertion support including random number generator shamelessly
3134 * stolen from kernel/rcutorture.c */
3135 struct fault_random_state {
3136 unsigned long state;
3137 unsigned long count;
3140 #define FAULT_RANDOM_MULT 39916801 /* prime */
3141 #define FAULT_RANDOM_ADD 479001701 /* prime */
3142 #define FAULT_RANDOM_REFRESH 10000
3145 * Crude but fast random-number generator. Uses a linear congruential
3146 * generator, with occasional help from get_random_bytes().
3148 static unsigned long
3149 _drbd_fault_random(struct fault_random_state *rsp)
3153 if (!rsp->count--) {
3154 get_random_bytes(&refresh, sizeof(refresh));
3155 rsp->state += refresh;
3156 rsp->count = FAULT_RANDOM_REFRESH;
3158 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
3159 return swahw32(rsp->state);
3163 _drbd_fault_str(unsigned int type) {
3164 static char *_faults[] = {
3165 [DRBD_FAULT_MD_WR] = "Meta-data write",
3166 [DRBD_FAULT_MD_RD] = "Meta-data read",
3167 [DRBD_FAULT_RS_WR] = "Resync write",
3168 [DRBD_FAULT_RS_RD] = "Resync read",
3169 [DRBD_FAULT_DT_WR] = "Data write",
3170 [DRBD_FAULT_DT_RD] = "Data read",
3171 [DRBD_FAULT_DT_RA] = "Data read ahead",
3172 [DRBD_FAULT_BM_ALLOC] = "BM allocation",
3173 [DRBD_FAULT_AL_EE] = "EE allocation",
3174 [DRBD_FAULT_RECEIVE] = "receive data corruption",
3177 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
3181 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
3183 static struct fault_random_state rrs = {0, 0};
3185 unsigned int ret = (
3187 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
3188 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
3193 if (__ratelimit(&drbd_ratelimit_state))
3194 dev_warn(DEV, "***Simulating %s failure\n",
3195 _drbd_fault_str(type));
3202 const char *drbd_buildtag(void)
3204 /* DRBD built from external sources has here a reference to the
3205 git hash of the source code. */
3207 static char buildtag[38] = "\0uilt-in";
3209 if (buildtag[0] == 0) {
3210 #ifdef CONFIG_MODULES
3211 if (THIS_MODULE != NULL)
3212 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
3221 module_init(drbd_init)
3222 module_exit(drbd_cleanup)
3224 EXPORT_SYMBOL(drbd_conn_str);
3225 EXPORT_SYMBOL(drbd_role_str);
3226 EXPORT_SYMBOL(drbd_disk_str);
3227 EXPORT_SYMBOL(drbd_set_st_err_str);