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1/*
2 drbd_worker.c
3
4 This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
5
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>.
9
10 drbd is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2, or (at your option)
13 any later version.
14
15 drbd is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
19
20 You should have received a copy of the GNU General Public License
21 along with drbd; see the file COPYING. If not, write to
22 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
23
24 */
25
26#include <linux/module.h>
27#include <linux/drbd.h>
28#include <linux/sched.h>
29#include <linux/wait.h>
30#include <linux/mm.h>
31#include <linux/memcontrol.h>
32#include <linux/mm_inline.h>
33#include <linux/slab.h>
34#include <linux/random.h>
35#include <linux/string.h>
36#include <linux/scatterlist.h>
37
38#include "drbd_int.h"
39#include "drbd_req.h"
40
41static int w_make_ov_request(struct drbd_conf *mdev, struct drbd_work *w, int cancel);
42static int w_make_resync_request(struct drbd_conf *mdev,
43 struct drbd_work *w, int cancel);
44
45
46
47/* endio handlers:
48 * drbd_md_io_complete (defined here)
49 * drbd_endio_pri (defined here)
50 * drbd_endio_sec (defined here)
51 * bm_async_io_complete (defined in drbd_bitmap.c)
52 *
53 * For all these callbacks, note the following:
54 * The callbacks will be called in irq context by the IDE drivers,
55 * and in Softirqs/Tasklets/BH context by the SCSI drivers.
56 * Try to get the locking right :)
57 *
58 */
59
60
61/* About the global_state_lock
62 Each state transition on an device holds a read lock. In case we have
63 to evaluate the sync after dependencies, we grab a write lock, because
64 we need stable states on all devices for that. */
65rwlock_t global_state_lock;
66
67/* used for synchronous meta data and bitmap IO
68 * submitted by drbd_md_sync_page_io()
69 */
70void drbd_md_io_complete(struct bio *bio, int error)
71{
72 struct drbd_md_io *md_io;
73
74 md_io = (struct drbd_md_io *)bio->bi_private;
75 md_io->error = error;
76
77 complete(&md_io->event);
78}
79
80/* reads on behalf of the partner,
81 * "submitted" by the receiver
82 */
83void drbd_endio_read_sec_final(struct drbd_epoch_entry *e) __releases(local)
84{
85 unsigned long flags = 0;
86 struct drbd_conf *mdev = e->mdev;
87
88 D_ASSERT(e->block_id != ID_VACANT);
89
90 spin_lock_irqsave(&mdev->req_lock, flags);
91 mdev->read_cnt += e->size >> 9;
92 list_del(&e->w.list);
93 if (list_empty(&mdev->read_ee))
94 wake_up(&mdev->ee_wait);
95 if (test_bit(__EE_WAS_ERROR, &e->flags))
96 __drbd_chk_io_error(mdev, false);
97 spin_unlock_irqrestore(&mdev->req_lock, flags);
98
99 drbd_queue_work(&mdev->data.work, &e->w);
100 put_ldev(mdev);
101}
102
103/* writes on behalf of the partner, or resync writes,
104 * "submitted" by the receiver, final stage. */
105static void drbd_endio_write_sec_final(struct drbd_epoch_entry *e) __releases(local)
106{
107 unsigned long flags = 0;
108 struct drbd_conf *mdev = e->mdev;
109 sector_t e_sector;
110 int do_wake;
111 int is_syncer_req;
112 int do_al_complete_io;
113
114 D_ASSERT(e->block_id != ID_VACANT);
115
116 /* after we moved e to done_ee,
117 * we may no longer access it,
118 * it may be freed/reused already!
119 * (as soon as we release the req_lock) */
120 e_sector = e->sector;
121 do_al_complete_io = e->flags & EE_CALL_AL_COMPLETE_IO;
122 is_syncer_req = is_syncer_block_id(e->block_id);
123
124 spin_lock_irqsave(&mdev->req_lock, flags);
125 mdev->writ_cnt += e->size >> 9;
126 list_del(&e->w.list); /* has been on active_ee or sync_ee */
127 list_add_tail(&e->w.list, &mdev->done_ee);
128
129 /* No hlist_del_init(&e->collision) here, we did not send the Ack yet,
130 * neither did we wake possibly waiting conflicting requests.
131 * done from "drbd_process_done_ee" within the appropriate w.cb
132 * (e_end_block/e_end_resync_block) or from _drbd_clear_done_ee */
133
134 do_wake = is_syncer_req
135 ? list_empty(&mdev->sync_ee)
136 : list_empty(&mdev->active_ee);
137
138 if (test_bit(__EE_WAS_ERROR, &e->flags))
139 __drbd_chk_io_error(mdev, false);
140 spin_unlock_irqrestore(&mdev->req_lock, flags);
141
142 if (is_syncer_req)
143 drbd_rs_complete_io(mdev, e_sector);
144
145 if (do_wake)
146 wake_up(&mdev->ee_wait);
147
148 if (do_al_complete_io)
149 drbd_al_complete_io(mdev, e_sector);
150
151 wake_asender(mdev);
152 put_ldev(mdev);
153}
154
155/* writes on behalf of the partner, or resync writes,
156 * "submitted" by the receiver.
157 */
158void drbd_endio_sec(struct bio *bio, int error)
159{
160 struct drbd_epoch_entry *e = bio->bi_private;
161 struct drbd_conf *mdev = e->mdev;
162 int uptodate = bio_flagged(bio, BIO_UPTODATE);
163 int is_write = bio_data_dir(bio) == WRITE;
164
165 if (error && __ratelimit(&drbd_ratelimit_state))
166 dev_warn(DEV, "%s: error=%d s=%llus\n",
167 is_write ? "write" : "read", error,
168 (unsigned long long)e->sector);
169 if (!error && !uptodate) {
170 if (__ratelimit(&drbd_ratelimit_state))
171 dev_warn(DEV, "%s: setting error to -EIO s=%llus\n",
172 is_write ? "write" : "read",
173 (unsigned long long)e->sector);
174 /* strange behavior of some lower level drivers...
175 * fail the request by clearing the uptodate flag,
176 * but do not return any error?! */
177 error = -EIO;
178 }
179
180 if (error)
181 set_bit(__EE_WAS_ERROR, &e->flags);
182
183 bio_put(bio); /* no need for the bio anymore */
184 if (atomic_dec_and_test(&e->pending_bios)) {
185 if (is_write)
186 drbd_endio_write_sec_final(e);
187 else
188 drbd_endio_read_sec_final(e);
189 }
190}
191
192/* read, readA or write requests on R_PRIMARY coming from drbd_make_request
193 */
194void drbd_endio_pri(struct bio *bio, int error)
195{
196 unsigned long flags;
197 struct drbd_request *req = bio->bi_private;
198 struct drbd_conf *mdev = req->mdev;
199 struct bio_and_error m;
200 enum drbd_req_event what;
201 int uptodate = bio_flagged(bio, BIO_UPTODATE);
202
203 if (!error && !uptodate) {
204 dev_warn(DEV, "p %s: setting error to -EIO\n",
205 bio_data_dir(bio) == WRITE ? "write" : "read");
206 /* strange behavior of some lower level drivers...
207 * fail the request by clearing the uptodate flag,
208 * but do not return any error?! */
209 error = -EIO;
210 }
211
212 /* to avoid recursion in __req_mod */
213 if (unlikely(error)) {
214 what = (bio_data_dir(bio) == WRITE)
215 ? write_completed_with_error
216 : (bio_rw(bio) == READ)
217 ? read_completed_with_error
218 : read_ahead_completed_with_error;
219 } else
220 what = completed_ok;
221
222 bio_put(req->private_bio);
223 req->private_bio = ERR_PTR(error);
224
225 /* not req_mod(), we need irqsave here! */
226 spin_lock_irqsave(&mdev->req_lock, flags);
227 __req_mod(req, what, &m);
228 spin_unlock_irqrestore(&mdev->req_lock, flags);
229
230 if (m.bio)
231 complete_master_bio(mdev, &m);
232}
233
234int w_read_retry_remote(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
235{
236 struct drbd_request *req = container_of(w, struct drbd_request, w);
237
238 /* We should not detach for read io-error,
239 * but try to WRITE the P_DATA_REPLY to the failed location,
240 * to give the disk the chance to relocate that block */
241
242 spin_lock_irq(&mdev->req_lock);
243 if (cancel || mdev->state.pdsk != D_UP_TO_DATE) {
244 _req_mod(req, read_retry_remote_canceled);
245 spin_unlock_irq(&mdev->req_lock);
246 return 1;
247 }
248 spin_unlock_irq(&mdev->req_lock);
249
250 return w_send_read_req(mdev, w, 0);
251}
252
253void drbd_csum_ee(struct drbd_conf *mdev, struct crypto_hash *tfm, struct drbd_epoch_entry *e, void *digest)
254{
255 struct hash_desc desc;
256 struct scatterlist sg;
257 struct page *page = e->pages;
258 struct page *tmp;
259 unsigned len;
260
261 desc.tfm = tfm;
262 desc.flags = 0;
263
264 sg_init_table(&sg, 1);
265 crypto_hash_init(&desc);
266
267 while ((tmp = page_chain_next(page))) {
268 /* all but the last page will be fully used */
269 sg_set_page(&sg, page, PAGE_SIZE, 0);
270 crypto_hash_update(&desc, &sg, sg.length);
271 page = tmp;
272 }
273 /* and now the last, possibly only partially used page */
274 len = e->size & (PAGE_SIZE - 1);
275 sg_set_page(&sg, page, len ?: PAGE_SIZE, 0);
276 crypto_hash_update(&desc, &sg, sg.length);
277 crypto_hash_final(&desc, digest);
278}
279
280void drbd_csum_bio(struct drbd_conf *mdev, struct crypto_hash *tfm, struct bio *bio, void *digest)
281{
282 struct hash_desc desc;
283 struct scatterlist sg;
284 struct bio_vec *bvec;
285 int i;
286
287 desc.tfm = tfm;
288 desc.flags = 0;
289
290 sg_init_table(&sg, 1);
291 crypto_hash_init(&desc);
292
293 __bio_for_each_segment(bvec, bio, i, 0) {
294 sg_set_page(&sg, bvec->bv_page, bvec->bv_len, bvec->bv_offset);
295 crypto_hash_update(&desc, &sg, sg.length);
296 }
297 crypto_hash_final(&desc, digest);
298}
299
300/* TODO merge common code with w_e_end_ov_req */
301int w_e_send_csum(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
302{
303 struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w);
304 int digest_size;
305 void *digest;
306 int ok = 1;
307
308 D_ASSERT(e->block_id == DRBD_MAGIC + 0xbeef);
309
310 if (unlikely(cancel))
311 goto out;
312
313 if (likely((e->flags & EE_WAS_ERROR) != 0))
314 goto out;
315
316 digest_size = crypto_hash_digestsize(mdev->csums_tfm);
317 digest = kmalloc(digest_size, GFP_NOIO);
318 if (digest) {
319 sector_t sector = e->sector;
320 unsigned int size = e->size;
321 drbd_csum_ee(mdev, mdev->csums_tfm, e, digest);
322 /* Free e and pages before send.
323 * In case we block on congestion, we could otherwise run into
324 * some distributed deadlock, if the other side blocks on
325 * congestion as well, because our receiver blocks in
326 * drbd_pp_alloc due to pp_in_use > max_buffers. */
327 drbd_free_ee(mdev, e);
328 e = NULL;
329 inc_rs_pending(mdev);
330 ok = drbd_send_drequest_csum(mdev, sector, size,
331 digest, digest_size,
332 P_CSUM_RS_REQUEST);
333 kfree(digest);
334 } else {
335 dev_err(DEV, "kmalloc() of digest failed.\n");
336 ok = 0;
337 }
338
339out:
340 if (e)
341 drbd_free_ee(mdev, e);
342
343 if (unlikely(!ok))
344 dev_err(DEV, "drbd_send_drequest(..., csum) failed\n");
345 return ok;
346}
347
348#define GFP_TRY (__GFP_HIGHMEM | __GFP_NOWARN)
349
350static int read_for_csum(struct drbd_conf *mdev, sector_t sector, int size)
351{
352 struct drbd_epoch_entry *e;
353
354 if (!get_ldev(mdev))
355 return -EIO;
356
357 if (drbd_rs_should_slow_down(mdev, sector))
358 goto defer;
359
360 /* GFP_TRY, because if there is no memory available right now, this may
361 * be rescheduled for later. It is "only" background resync, after all. */
362 e = drbd_alloc_ee(mdev, DRBD_MAGIC+0xbeef, sector, size, GFP_TRY);
363 if (!e)
364 goto defer;
365
366 e->w.cb = w_e_send_csum;
367 spin_lock_irq(&mdev->req_lock);
368 list_add(&e->w.list, &mdev->read_ee);
369 spin_unlock_irq(&mdev->req_lock);
370
371 atomic_add(size >> 9, &mdev->rs_sect_ev);
372 if (drbd_submit_ee(mdev, e, READ, DRBD_FAULT_RS_RD) == 0)
373 return 0;
374
375 /* If it failed because of ENOMEM, retry should help. If it failed
376 * because bio_add_page failed (probably broken lower level driver),
377 * retry may or may not help.
378 * If it does not, you may need to force disconnect. */
379 spin_lock_irq(&mdev->req_lock);
380 list_del(&e->w.list);
381 spin_unlock_irq(&mdev->req_lock);
382
383 drbd_free_ee(mdev, e);
384defer:
385 put_ldev(mdev);
386 return -EAGAIN;
387}
388
389int w_resync_timer(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
390{
391 switch (mdev->state.conn) {
392 case C_VERIFY_S:
393 w_make_ov_request(mdev, w, cancel);
394 break;
395 case C_SYNC_TARGET:
396 w_make_resync_request(mdev, w, cancel);
397 break;
398 }
399
400 return 1;
401}
402
403void resync_timer_fn(unsigned long data)
404{
405 struct drbd_conf *mdev = (struct drbd_conf *) data;
406
407 if (list_empty(&mdev->resync_work.list))
408 drbd_queue_work(&mdev->data.work, &mdev->resync_work);
409}
410
411static void fifo_set(struct fifo_buffer *fb, int value)
412{
413 int i;
414
415 for (i = 0; i < fb->size; i++)
416 fb->values[i] = value;
417}
418
419static int fifo_push(struct fifo_buffer *fb, int value)
420{
421 int ov;
422
423 ov = fb->values[fb->head_index];
424 fb->values[fb->head_index++] = value;
425
426 if (fb->head_index >= fb->size)
427 fb->head_index = 0;
428
429 return ov;
430}
431
432static void fifo_add_val(struct fifo_buffer *fb, int value)
433{
434 int i;
435
436 for (i = 0; i < fb->size; i++)
437 fb->values[i] += value;
438}
439
440static int drbd_rs_controller(struct drbd_conf *mdev)
441{
442 unsigned int sect_in; /* Number of sectors that came in since the last turn */
443 unsigned int want; /* The number of sectors we want in the proxy */
444 int req_sect; /* Number of sectors to request in this turn */
445 int correction; /* Number of sectors more we need in the proxy*/
446 int cps; /* correction per invocation of drbd_rs_controller() */
447 int steps; /* Number of time steps to plan ahead */
448 int curr_corr;
449 int max_sect;
450
451 sect_in = atomic_xchg(&mdev->rs_sect_in, 0); /* Number of sectors that came in */
452 mdev->rs_in_flight -= sect_in;
453
454 spin_lock(&mdev->peer_seq_lock); /* get an atomic view on mdev->rs_plan_s */
455
456 steps = mdev->rs_plan_s.size; /* (mdev->sync_conf.c_plan_ahead * 10 * SLEEP_TIME) / HZ; */
457
458 if (mdev->rs_in_flight + sect_in == 0) { /* At start of resync */
459 want = ((mdev->sync_conf.rate * 2 * SLEEP_TIME) / HZ) * steps;
460 } else { /* normal path */
461 want = mdev->sync_conf.c_fill_target ? mdev->sync_conf.c_fill_target :
462 sect_in * mdev->sync_conf.c_delay_target * HZ / (SLEEP_TIME * 10);
463 }
464
465 correction = want - mdev->rs_in_flight - mdev->rs_planed;
466
467 /* Plan ahead */
468 cps = correction / steps;
469 fifo_add_val(&mdev->rs_plan_s, cps);
470 mdev->rs_planed += cps * steps;
471
472 /* What we do in this step */
473 curr_corr = fifo_push(&mdev->rs_plan_s, 0);
474 spin_unlock(&mdev->peer_seq_lock);
475 mdev->rs_planed -= curr_corr;
476
477 req_sect = sect_in + curr_corr;
478 if (req_sect < 0)
479 req_sect = 0;
480
481 max_sect = (mdev->sync_conf.c_max_rate * 2 * SLEEP_TIME) / HZ;
482 if (req_sect > max_sect)
483 req_sect = max_sect;
484
485 /*
486 dev_warn(DEV, "si=%u if=%d wa=%u co=%d st=%d cps=%d pl=%d cc=%d rs=%d\n",
487 sect_in, mdev->rs_in_flight, want, correction,
488 steps, cps, mdev->rs_planed, curr_corr, req_sect);
489 */
490
491 return req_sect;
492}
493
494static int drbd_rs_number_requests(struct drbd_conf *mdev)
495{
496 int number;
497 if (mdev->rs_plan_s.size) { /* mdev->sync_conf.c_plan_ahead */
498 number = drbd_rs_controller(mdev) >> (BM_BLOCK_SHIFT - 9);
499 mdev->c_sync_rate = number * HZ * (BM_BLOCK_SIZE / 1024) / SLEEP_TIME;
500 } else {
501 mdev->c_sync_rate = mdev->sync_conf.rate;
502 number = SLEEP_TIME * mdev->c_sync_rate / ((BM_BLOCK_SIZE / 1024) * HZ);
503 }
504
505 /* ignore the amount of pending requests, the resync controller should
506 * throttle down to incoming reply rate soon enough anyways. */
507 return number;
508}
509
510static int w_make_resync_request(struct drbd_conf *mdev,
511 struct drbd_work *w, int cancel)
512{
513 unsigned long bit;
514 sector_t sector;
515 const sector_t capacity = drbd_get_capacity(mdev->this_bdev);
516 int max_bio_size;
517 int number, rollback_i, size;
518 int align, queued, sndbuf;
519 int i = 0;
520
521 if (unlikely(cancel))
522 return 1;
523
524 if (mdev->rs_total == 0) {
525 /* empty resync? */
526 drbd_resync_finished(mdev);
527 return 1;
528 }
529
530 if (!get_ldev(mdev)) {
531 /* Since we only need to access mdev->rsync a
532 get_ldev_if_state(mdev,D_FAILED) would be sufficient, but
533 to continue resync with a broken disk makes no sense at
534 all */
535 dev_err(DEV, "Disk broke down during resync!\n");
536 return 1;
537 }
538
539 max_bio_size = queue_max_hw_sectors(mdev->rq_queue) << 9;
540 number = drbd_rs_number_requests(mdev);
541 if (number == 0)
542 goto requeue;
543
544 for (i = 0; i < number; i++) {
545 /* Stop generating RS requests, when half of the send buffer is filled */
546 mutex_lock(&mdev->data.mutex);
547 if (mdev->data.socket) {
548 queued = mdev->data.socket->sk->sk_wmem_queued;
549 sndbuf = mdev->data.socket->sk->sk_sndbuf;
550 } else {
551 queued = 1;
552 sndbuf = 0;
553 }
554 mutex_unlock(&mdev->data.mutex);
555 if (queued > sndbuf / 2)
556 goto requeue;
557
558next_sector:
559 size = BM_BLOCK_SIZE;
560 bit = drbd_bm_find_next(mdev, mdev->bm_resync_fo);
561
562 if (bit == DRBD_END_OF_BITMAP) {
563 mdev->bm_resync_fo = drbd_bm_bits(mdev);
564 put_ldev(mdev);
565 return 1;
566 }
567
568 sector = BM_BIT_TO_SECT(bit);
569
570 if (drbd_rs_should_slow_down(mdev, sector) ||
571 drbd_try_rs_begin_io(mdev, sector)) {
572 mdev->bm_resync_fo = bit;
573 goto requeue;
574 }
575 mdev->bm_resync_fo = bit + 1;
576
577 if (unlikely(drbd_bm_test_bit(mdev, bit) == 0)) {
578 drbd_rs_complete_io(mdev, sector);
579 goto next_sector;
580 }
581
582#if DRBD_MAX_BIO_SIZE > BM_BLOCK_SIZE
583 /* try to find some adjacent bits.
584 * we stop if we have already the maximum req size.
585 *
586 * Additionally always align bigger requests, in order to
587 * be prepared for all stripe sizes of software RAIDs.
588 */
589 align = 1;
590 rollback_i = i;
591 for (;;) {
592 if (size + BM_BLOCK_SIZE > max_bio_size)
593 break;
594
595 /* Be always aligned */
596 if (sector & ((1<<(align+3))-1))
597 break;
598
599 /* do not cross extent boundaries */
600 if (((bit+1) & BM_BLOCKS_PER_BM_EXT_MASK) == 0)
601 break;
602 /* now, is it actually dirty, after all?
603 * caution, drbd_bm_test_bit is tri-state for some
604 * obscure reason; ( b == 0 ) would get the out-of-band
605 * only accidentally right because of the "oddly sized"
606 * adjustment below */
607 if (drbd_bm_test_bit(mdev, bit+1) != 1)
608 break;
609 bit++;
610 size += BM_BLOCK_SIZE;
611 if ((BM_BLOCK_SIZE << align) <= size)
612 align++;
613 i++;
614 }
615 /* if we merged some,
616 * reset the offset to start the next drbd_bm_find_next from */
617 if (size > BM_BLOCK_SIZE)
618 mdev->bm_resync_fo = bit + 1;
619#endif
620
621 /* adjust very last sectors, in case we are oddly sized */
622 if (sector + (size>>9) > capacity)
623 size = (capacity-sector)<<9;
624 if (mdev->agreed_pro_version >= 89 && mdev->csums_tfm) {
625 switch (read_for_csum(mdev, sector, size)) {
626 case -EIO: /* Disk failure */
627 put_ldev(mdev);
628 return 0;
629 case -EAGAIN: /* allocation failed, or ldev busy */
630 drbd_rs_complete_io(mdev, sector);
631 mdev->bm_resync_fo = BM_SECT_TO_BIT(sector);
632 i = rollback_i;
633 goto requeue;
634 case 0:
635 /* everything ok */
636 break;
637 default:
638 BUG();
639 }
640 } else {
641 inc_rs_pending(mdev);
642 if (!drbd_send_drequest(mdev, P_RS_DATA_REQUEST,
643 sector, size, ID_SYNCER)) {
644 dev_err(DEV, "drbd_send_drequest() failed, aborting...\n");
645 dec_rs_pending(mdev);
646 put_ldev(mdev);
647 return 0;
648 }
649 }
650 }
651
652 if (mdev->bm_resync_fo >= drbd_bm_bits(mdev)) {
653 /* last syncer _request_ was sent,
654 * but the P_RS_DATA_REPLY not yet received. sync will end (and
655 * next sync group will resume), as soon as we receive the last
656 * resync data block, and the last bit is cleared.
657 * until then resync "work" is "inactive" ...
658 */
659 put_ldev(mdev);
660 return 1;
661 }
662
663 requeue:
664 mdev->rs_in_flight += (i << (BM_BLOCK_SHIFT - 9));
665 mod_timer(&mdev->resync_timer, jiffies + SLEEP_TIME);
666 put_ldev(mdev);
667 return 1;
668}
669
670static int w_make_ov_request(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
671{
672 int number, i, size;
673 sector_t sector;
674 const sector_t capacity = drbd_get_capacity(mdev->this_bdev);
675
676 if (unlikely(cancel))
677 return 1;
678
679 number = drbd_rs_number_requests(mdev);
680
681 sector = mdev->ov_position;
682 for (i = 0; i < number; i++) {
683 if (sector >= capacity) {
684 return 1;
685 }
686
687 size = BM_BLOCK_SIZE;
688
689 if (drbd_rs_should_slow_down(mdev, sector) ||
690 drbd_try_rs_begin_io(mdev, sector)) {
691 mdev->ov_position = sector;
692 goto requeue;
693 }
694
695 if (sector + (size>>9) > capacity)
696 size = (capacity-sector)<<9;
697
698 inc_rs_pending(mdev);
699 if (!drbd_send_ov_request(mdev, sector, size)) {
700 dec_rs_pending(mdev);
701 return 0;
702 }
703 sector += BM_SECT_PER_BIT;
704 }
705 mdev->ov_position = sector;
706
707 requeue:
708 mdev->rs_in_flight += (i << (BM_BLOCK_SHIFT - 9));
709 mod_timer(&mdev->resync_timer, jiffies + SLEEP_TIME);
710 return 1;
711}
712
713
714void start_resync_timer_fn(unsigned long data)
715{
716 struct drbd_conf *mdev = (struct drbd_conf *) data;
717
718 drbd_queue_work(&mdev->data.work, &mdev->start_resync_work);
719}
720
721int w_start_resync(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
722{
723 if (atomic_read(&mdev->unacked_cnt) || atomic_read(&mdev->rs_pending_cnt)) {
724 dev_warn(DEV, "w_start_resync later...\n");
725 mdev->start_resync_timer.expires = jiffies + HZ/10;
726 add_timer(&mdev->start_resync_timer);
727 return 1;
728 }
729
730 drbd_start_resync(mdev, C_SYNC_SOURCE);
731 clear_bit(AHEAD_TO_SYNC_SOURCE, &mdev->current_epoch->flags);
732 return 1;
733}
734
735int w_ov_finished(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
736{
737 kfree(w);
738 ov_oos_print(mdev);
739 drbd_resync_finished(mdev);
740
741 return 1;
742}
743
744static int w_resync_finished(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
745{
746 kfree(w);
747
748 drbd_resync_finished(mdev);
749
750 return 1;
751}
752
753static void ping_peer(struct drbd_conf *mdev)
754{
755 clear_bit(GOT_PING_ACK, &mdev->flags);
756 request_ping(mdev);
757 wait_event(mdev->misc_wait,
758 test_bit(GOT_PING_ACK, &mdev->flags) || mdev->state.conn < C_CONNECTED);
759}
760
761int drbd_resync_finished(struct drbd_conf *mdev)
762{
763 unsigned long db, dt, dbdt;
764 unsigned long n_oos;
765 union drbd_state os, ns;
766 struct drbd_work *w;
767 char *khelper_cmd = NULL;
768 int verify_done = 0;
769
770 /* Remove all elements from the resync LRU. Since future actions
771 * might set bits in the (main) bitmap, then the entries in the
772 * resync LRU would be wrong. */
773 if (drbd_rs_del_all(mdev)) {
774 /* In case this is not possible now, most probably because
775 * there are P_RS_DATA_REPLY Packets lingering on the worker's
776 * queue (or even the read operations for those packets
777 * is not finished by now). Retry in 100ms. */
778
779 schedule_timeout_interruptible(HZ / 10);
780 w = kmalloc(sizeof(struct drbd_work), GFP_ATOMIC);
781 if (w) {
782 w->cb = w_resync_finished;
783 drbd_queue_work(&mdev->data.work, w);
784 return 1;
785 }
786 dev_err(DEV, "Warn failed to drbd_rs_del_all() and to kmalloc(w).\n");
787 }
788
789 dt = (jiffies - mdev->rs_start - mdev->rs_paused) / HZ;
790 if (dt <= 0)
791 dt = 1;
792 db = mdev->rs_total;
793 dbdt = Bit2KB(db/dt);
794 mdev->rs_paused /= HZ;
795
796 if (!get_ldev(mdev))
797 goto out;
798
799 ping_peer(mdev);
800
801 spin_lock_irq(&mdev->req_lock);
802 os = mdev->state;
803
804 verify_done = (os.conn == C_VERIFY_S || os.conn == C_VERIFY_T);
805
806 /* This protects us against multiple calls (that can happen in the presence
807 of application IO), and against connectivity loss just before we arrive here. */
808 if (os.conn <= C_CONNECTED)
809 goto out_unlock;
810
811 ns = os;
812 ns.conn = C_CONNECTED;
813
814 dev_info(DEV, "%s done (total %lu sec; paused %lu sec; %lu K/sec)\n",
815 verify_done ? "Online verify " : "Resync",
816 dt + mdev->rs_paused, mdev->rs_paused, dbdt);
817
818 n_oos = drbd_bm_total_weight(mdev);
819
820 if (os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) {
821 if (n_oos) {
822 dev_alert(DEV, "Online verify found %lu %dk block out of sync!\n",
823 n_oos, Bit2KB(1));
824 khelper_cmd = "out-of-sync";
825 }
826 } else {
827 D_ASSERT((n_oos - mdev->rs_failed) == 0);
828
829 if (os.conn == C_SYNC_TARGET || os.conn == C_PAUSED_SYNC_T)
830 khelper_cmd = "after-resync-target";
831
832 if (mdev->csums_tfm && mdev->rs_total) {
833 const unsigned long s = mdev->rs_same_csum;
834 const unsigned long t = mdev->rs_total;
835 const int ratio =
836 (t == 0) ? 0 :
837 (t < 100000) ? ((s*100)/t) : (s/(t/100));
838 dev_info(DEV, "%u %% had equal checksums, eliminated: %luK; "
839 "transferred %luK total %luK\n",
840 ratio,
841 Bit2KB(mdev->rs_same_csum),
842 Bit2KB(mdev->rs_total - mdev->rs_same_csum),
843 Bit2KB(mdev->rs_total));
844 }
845 }
846
847 if (mdev->rs_failed) {
848 dev_info(DEV, " %lu failed blocks\n", mdev->rs_failed);
849
850 if (os.conn == C_SYNC_TARGET || os.conn == C_PAUSED_SYNC_T) {
851 ns.disk = D_INCONSISTENT;
852 ns.pdsk = D_UP_TO_DATE;
853 } else {
854 ns.disk = D_UP_TO_DATE;
855 ns.pdsk = D_INCONSISTENT;
856 }
857 } else {
858 ns.disk = D_UP_TO_DATE;
859 ns.pdsk = D_UP_TO_DATE;
860
861 if (os.conn == C_SYNC_TARGET || os.conn == C_PAUSED_SYNC_T) {
862 if (mdev->p_uuid) {
863 int i;
864 for (i = UI_BITMAP ; i <= UI_HISTORY_END ; i++)
865 _drbd_uuid_set(mdev, i, mdev->p_uuid[i]);
866 drbd_uuid_set(mdev, UI_BITMAP, mdev->ldev->md.uuid[UI_CURRENT]);
867 _drbd_uuid_set(mdev, UI_CURRENT, mdev->p_uuid[UI_CURRENT]);
868 } else {
869 dev_err(DEV, "mdev->p_uuid is NULL! BUG\n");
870 }
871 }
872
873 if (!(os.conn == C_VERIFY_S || os.conn == C_VERIFY_T)) {
874 /* for verify runs, we don't update uuids here,
875 * so there would be nothing to report. */
876 drbd_uuid_set_bm(mdev, 0UL);
877 drbd_print_uuids(mdev, "updated UUIDs");
878 if (mdev->p_uuid) {
879 /* Now the two UUID sets are equal, update what we
880 * know of the peer. */
881 int i;
882 for (i = UI_CURRENT ; i <= UI_HISTORY_END ; i++)
883 mdev->p_uuid[i] = mdev->ldev->md.uuid[i];
884 }
885 }
886 }
887
888 _drbd_set_state(mdev, ns, CS_VERBOSE, NULL);
889out_unlock:
890 spin_unlock_irq(&mdev->req_lock);
891 put_ldev(mdev);
892out:
893 mdev->rs_total = 0;
894 mdev->rs_failed = 0;
895 mdev->rs_paused = 0;
896 if (verify_done)
897 mdev->ov_start_sector = 0;
898
899 drbd_md_sync(mdev);
900
901 if (khelper_cmd)
902 drbd_khelper(mdev, khelper_cmd);
903
904 return 1;
905}
906
907/* helper */
908static void move_to_net_ee_or_free(struct drbd_conf *mdev, struct drbd_epoch_entry *e)
909{
910 if (drbd_ee_has_active_page(e)) {
911 /* This might happen if sendpage() has not finished */
912 int i = (e->size + PAGE_SIZE -1) >> PAGE_SHIFT;
913 atomic_add(i, &mdev->pp_in_use_by_net);
914 atomic_sub(i, &mdev->pp_in_use);
915 spin_lock_irq(&mdev->req_lock);
916 list_add_tail(&e->w.list, &mdev->net_ee);
917 spin_unlock_irq(&mdev->req_lock);
918 wake_up(&drbd_pp_wait);
919 } else
920 drbd_free_ee(mdev, e);
921}
922
923/**
924 * w_e_end_data_req() - Worker callback, to send a P_DATA_REPLY packet in response to a P_DATA_REQUEST
925 * @mdev: DRBD device.
926 * @w: work object.
927 * @cancel: The connection will be closed anyways
928 */
929int w_e_end_data_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
930{
931 struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w);
932 int ok;
933
934 if (unlikely(cancel)) {
935 drbd_free_ee(mdev, e);
936 dec_unacked(mdev);
937 return 1;
938 }
939
940 if (likely((e->flags & EE_WAS_ERROR) == 0)) {
941 ok = drbd_send_block(mdev, P_DATA_REPLY, e);
942 } else {
943 if (__ratelimit(&drbd_ratelimit_state))
944 dev_err(DEV, "Sending NegDReply. sector=%llus.\n",
945 (unsigned long long)e->sector);
946
947 ok = drbd_send_ack(mdev, P_NEG_DREPLY, e);
948 }
949
950 dec_unacked(mdev);
951
952 move_to_net_ee_or_free(mdev, e);
953
954 if (unlikely(!ok))
955 dev_err(DEV, "drbd_send_block() failed\n");
956 return ok;
957}
958
959/**
960 * w_e_end_rsdata_req() - Worker callback to send a P_RS_DATA_REPLY packet in response to a P_RS_DATA_REQUESTRS
961 * @mdev: DRBD device.
962 * @w: work object.
963 * @cancel: The connection will be closed anyways
964 */
965int w_e_end_rsdata_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
966{
967 struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w);
968 int ok;
969
970 if (unlikely(cancel)) {
971 drbd_free_ee(mdev, e);
972 dec_unacked(mdev);
973 return 1;
974 }
975
976 if (get_ldev_if_state(mdev, D_FAILED)) {
977 drbd_rs_complete_io(mdev, e->sector);
978 put_ldev(mdev);
979 }
980
981 if (mdev->state.conn == C_AHEAD) {
982 ok = drbd_send_ack(mdev, P_RS_CANCEL, e);
983 } else if (likely((e->flags & EE_WAS_ERROR) == 0)) {
984 if (likely(mdev->state.pdsk >= D_INCONSISTENT)) {
985 inc_rs_pending(mdev);
986 ok = drbd_send_block(mdev, P_RS_DATA_REPLY, e);
987 } else {
988 if (__ratelimit(&drbd_ratelimit_state))
989 dev_err(DEV, "Not sending RSDataReply, "
990 "partner DISKLESS!\n");
991 ok = 1;
992 }
993 } else {
994 if (__ratelimit(&drbd_ratelimit_state))
995 dev_err(DEV, "Sending NegRSDReply. sector %llus.\n",
996 (unsigned long long)e->sector);
997
998 ok = drbd_send_ack(mdev, P_NEG_RS_DREPLY, e);
999
1000 /* update resync data with failure */
1001 drbd_rs_failed_io(mdev, e->sector, e->size);
1002 }
1003
1004 dec_unacked(mdev);
1005
1006 move_to_net_ee_or_free(mdev, e);
1007
1008 if (unlikely(!ok))
1009 dev_err(DEV, "drbd_send_block() failed\n");
1010 return ok;
1011}
1012
1013int w_e_end_csum_rs_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1014{
1015 struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w);
1016 struct digest_info *di;
1017 int digest_size;
1018 void *digest = NULL;
1019 int ok, eq = 0;
1020
1021 if (unlikely(cancel)) {
1022 drbd_free_ee(mdev, e);
1023 dec_unacked(mdev);
1024 return 1;
1025 }
1026
1027 if (get_ldev(mdev)) {
1028 drbd_rs_complete_io(mdev, e->sector);
1029 put_ldev(mdev);
1030 }
1031
1032 di = e->digest;
1033
1034 if (likely((e->flags & EE_WAS_ERROR) == 0)) {
1035 /* quick hack to try to avoid a race against reconfiguration.
1036 * a real fix would be much more involved,
1037 * introducing more locking mechanisms */
1038 if (mdev->csums_tfm) {
1039 digest_size = crypto_hash_digestsize(mdev->csums_tfm);
1040 D_ASSERT(digest_size == di->digest_size);
1041 digest = kmalloc(digest_size, GFP_NOIO);
1042 }
1043 if (digest) {
1044 drbd_csum_ee(mdev, mdev->csums_tfm, e, digest);
1045 eq = !memcmp(digest, di->digest, digest_size);
1046 kfree(digest);
1047 }
1048
1049 if (eq) {
1050 drbd_set_in_sync(mdev, e->sector, e->size);
1051 /* rs_same_csums unit is BM_BLOCK_SIZE */
1052 mdev->rs_same_csum += e->size >> BM_BLOCK_SHIFT;
1053 ok = drbd_send_ack(mdev, P_RS_IS_IN_SYNC, e);
1054 } else {
1055 inc_rs_pending(mdev);
1056 e->block_id = ID_SYNCER; /* By setting block_id, digest pointer becomes invalid! */
1057 e->flags &= ~EE_HAS_DIGEST; /* This e no longer has a digest pointer */
1058 kfree(di);
1059 ok = drbd_send_block(mdev, P_RS_DATA_REPLY, e);
1060 }
1061 } else {
1062 ok = drbd_send_ack(mdev, P_NEG_RS_DREPLY, e);
1063 if (__ratelimit(&drbd_ratelimit_state))
1064 dev_err(DEV, "Sending NegDReply. I guess it gets messy.\n");
1065 }
1066
1067 dec_unacked(mdev);
1068 move_to_net_ee_or_free(mdev, e);
1069
1070 if (unlikely(!ok))
1071 dev_err(DEV, "drbd_send_block/ack() failed\n");
1072 return ok;
1073}
1074
1075/* TODO merge common code with w_e_send_csum */
1076int w_e_end_ov_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1077{
1078 struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w);
1079 sector_t sector = e->sector;
1080 unsigned int size = e->size;
1081 int digest_size;
1082 void *digest;
1083 int ok = 1;
1084
1085 if (unlikely(cancel))
1086 goto out;
1087
1088 digest_size = crypto_hash_digestsize(mdev->verify_tfm);
1089 digest = kmalloc(digest_size, GFP_NOIO);
1090 if (!digest) {
1091 ok = 0; /* terminate the connection in case the allocation failed */
1092 goto out;
1093 }
1094
1095 if (likely(!(e->flags & EE_WAS_ERROR)))
1096 drbd_csum_ee(mdev, mdev->verify_tfm, e, digest);
1097 else
1098 memset(digest, 0, digest_size);
1099
1100 /* Free e and pages before send.
1101 * In case we block on congestion, we could otherwise run into
1102 * some distributed deadlock, if the other side blocks on
1103 * congestion as well, because our receiver blocks in
1104 * drbd_pp_alloc due to pp_in_use > max_buffers. */
1105 drbd_free_ee(mdev, e);
1106 e = NULL;
1107 inc_rs_pending(mdev);
1108 ok = drbd_send_drequest_csum(mdev, sector, size,
1109 digest, digest_size,
1110 P_OV_REPLY);
1111 if (!ok)
1112 dec_rs_pending(mdev);
1113 kfree(digest);
1114
1115out:
1116 if (e)
1117 drbd_free_ee(mdev, e);
1118 dec_unacked(mdev);
1119 return ok;
1120}
1121
1122void drbd_ov_oos_found(struct drbd_conf *mdev, sector_t sector, int size)
1123{
1124 if (mdev->ov_last_oos_start + mdev->ov_last_oos_size == sector) {
1125 mdev->ov_last_oos_size += size>>9;
1126 } else {
1127 mdev->ov_last_oos_start = sector;
1128 mdev->ov_last_oos_size = size>>9;
1129 }
1130 drbd_set_out_of_sync(mdev, sector, size);
1131}
1132
1133int w_e_end_ov_reply(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1134{
1135 struct drbd_epoch_entry *e = container_of(w, struct drbd_epoch_entry, w);
1136 struct digest_info *di;
1137 void *digest;
1138 sector_t sector = e->sector;
1139 unsigned int size = e->size;
1140 int digest_size;
1141 int ok, eq = 0;
1142
1143 if (unlikely(cancel)) {
1144 drbd_free_ee(mdev, e);
1145 dec_unacked(mdev);
1146 return 1;
1147 }
1148
1149 /* after "cancel", because after drbd_disconnect/drbd_rs_cancel_all
1150 * the resync lru has been cleaned up already */
1151 if (get_ldev(mdev)) {
1152 drbd_rs_complete_io(mdev, e->sector);
1153 put_ldev(mdev);
1154 }
1155
1156 di = e->digest;
1157
1158 if (likely((e->flags & EE_WAS_ERROR) == 0)) {
1159 digest_size = crypto_hash_digestsize(mdev->verify_tfm);
1160 digest = kmalloc(digest_size, GFP_NOIO);
1161 if (digest) {
1162 drbd_csum_ee(mdev, mdev->verify_tfm, e, digest);
1163
1164 D_ASSERT(digest_size == di->digest_size);
1165 eq = !memcmp(digest, di->digest, digest_size);
1166 kfree(digest);
1167 }
1168 }
1169
1170 /* Free e and pages before send.
1171 * In case we block on congestion, we could otherwise run into
1172 * some distributed deadlock, if the other side blocks on
1173 * congestion as well, because our receiver blocks in
1174 * drbd_pp_alloc due to pp_in_use > max_buffers. */
1175 drbd_free_ee(mdev, e);
1176 if (!eq)
1177 drbd_ov_oos_found(mdev, sector, size);
1178 else
1179 ov_oos_print(mdev);
1180
1181 ok = drbd_send_ack_ex(mdev, P_OV_RESULT, sector, size,
1182 eq ? ID_IN_SYNC : ID_OUT_OF_SYNC);
1183
1184 dec_unacked(mdev);
1185
1186 --mdev->ov_left;
1187
1188 /* let's advance progress step marks only for every other megabyte */
1189 if ((mdev->ov_left & 0x200) == 0x200)
1190 drbd_advance_rs_marks(mdev, mdev->ov_left);
1191
1192 if (mdev->ov_left == 0) {
1193 ov_oos_print(mdev);
1194 drbd_resync_finished(mdev);
1195 }
1196
1197 return ok;
1198}
1199
1200int w_prev_work_done(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1201{
1202 struct drbd_wq_barrier *b = container_of(w, struct drbd_wq_barrier, w);
1203 complete(&b->done);
1204 return 1;
1205}
1206
1207int w_send_barrier(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1208{
1209 struct drbd_tl_epoch *b = container_of(w, struct drbd_tl_epoch, w);
1210 struct p_barrier *p = &mdev->data.sbuf.barrier;
1211 int ok = 1;
1212
1213 /* really avoid racing with tl_clear. w.cb may have been referenced
1214 * just before it was reassigned and re-queued, so double check that.
1215 * actually, this race was harmless, since we only try to send the
1216 * barrier packet here, and otherwise do nothing with the object.
1217 * but compare with the head of w_clear_epoch */
1218 spin_lock_irq(&mdev->req_lock);
1219 if (w->cb != w_send_barrier || mdev->state.conn < C_CONNECTED)
1220 cancel = 1;
1221 spin_unlock_irq(&mdev->req_lock);
1222 if (cancel)
1223 return 1;
1224
1225 if (!drbd_get_data_sock(mdev))
1226 return 0;
1227 p->barrier = b->br_number;
1228 /* inc_ap_pending was done where this was queued.
1229 * dec_ap_pending will be done in got_BarrierAck
1230 * or (on connection loss) in w_clear_epoch. */
1231 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BARRIER,
1232 (struct p_header80 *)p, sizeof(*p), 0);
1233 drbd_put_data_sock(mdev);
1234
1235 return ok;
1236}
1237
1238int w_send_write_hint(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1239{
1240 if (cancel)
1241 return 1;
1242 return drbd_send_short_cmd(mdev, P_UNPLUG_REMOTE);
1243}
1244
1245int w_send_oos(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1246{
1247 struct drbd_request *req = container_of(w, struct drbd_request, w);
1248 int ok;
1249
1250 if (unlikely(cancel)) {
1251 req_mod(req, send_canceled);
1252 return 1;
1253 }
1254
1255 ok = drbd_send_oos(mdev, req);
1256 req_mod(req, oos_handed_to_network);
1257
1258 return ok;
1259}
1260
1261/**
1262 * w_send_dblock() - Worker callback to send a P_DATA packet in order to mirror a write request
1263 * @mdev: DRBD device.
1264 * @w: work object.
1265 * @cancel: The connection will be closed anyways
1266 */
1267int w_send_dblock(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1268{
1269 struct drbd_request *req = container_of(w, struct drbd_request, w);
1270 int ok;
1271
1272 if (unlikely(cancel)) {
1273 req_mod(req, send_canceled);
1274 return 1;
1275 }
1276
1277 ok = drbd_send_dblock(mdev, req);
1278 req_mod(req, ok ? handed_over_to_network : send_failed);
1279
1280 return ok;
1281}
1282
1283/**
1284 * w_send_read_req() - Worker callback to send a read request (P_DATA_REQUEST) packet
1285 * @mdev: DRBD device.
1286 * @w: work object.
1287 * @cancel: The connection will be closed anyways
1288 */
1289int w_send_read_req(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1290{
1291 struct drbd_request *req = container_of(w, struct drbd_request, w);
1292 int ok;
1293
1294 if (unlikely(cancel)) {
1295 req_mod(req, send_canceled);
1296 return 1;
1297 }
1298
1299 ok = drbd_send_drequest(mdev, P_DATA_REQUEST, req->sector, req->size,
1300 (unsigned long)req);
1301
1302 if (!ok) {
1303 /* ?? we set C_TIMEOUT or C_BROKEN_PIPE in drbd_send();
1304 * so this is probably redundant */
1305 if (mdev->state.conn >= C_CONNECTED)
1306 drbd_force_state(mdev, NS(conn, C_NETWORK_FAILURE));
1307 }
1308 req_mod(req, ok ? handed_over_to_network : send_failed);
1309
1310 return ok;
1311}
1312
1313int w_restart_disk_io(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
1314{
1315 struct drbd_request *req = container_of(w, struct drbd_request, w);
1316
1317 if (bio_data_dir(req->master_bio) == WRITE && req->rq_state & RQ_IN_ACT_LOG)
1318 drbd_al_begin_io(mdev, req->sector);
1319 /* Calling drbd_al_begin_io() out of the worker might deadlocks
1320 theoretically. Practically it can not deadlock, since this is
1321 only used when unfreezing IOs. All the extents of the requests
1322 that made it into the TL are already active */
1323
1324 drbd_req_make_private_bio(req, req->master_bio);
1325 req->private_bio->bi_bdev = mdev->ldev->backing_bdev;
1326 generic_make_request(req->private_bio);
1327
1328 return 1;
1329}
1330
1331static int _drbd_may_sync_now(struct drbd_conf *mdev)
1332{
1333 struct drbd_conf *odev = mdev;
1334
1335 while (1) {
1336 if (odev->sync_conf.after == -1)
1337 return 1;
1338 odev = minor_to_mdev(odev->sync_conf.after);
1339 ERR_IF(!odev) return 1;
1340 if ((odev->state.conn >= C_SYNC_SOURCE &&
1341 odev->state.conn <= C_PAUSED_SYNC_T) ||
1342 odev->state.aftr_isp || odev->state.peer_isp ||
1343 odev->state.user_isp)
1344 return 0;
1345 }
1346}
1347
1348/**
1349 * _drbd_pause_after() - Pause resync on all devices that may not resync now
1350 * @mdev: DRBD device.
1351 *
1352 * Called from process context only (admin command and after_state_ch).
1353 */
1354static int _drbd_pause_after(struct drbd_conf *mdev)
1355{
1356 struct drbd_conf *odev;
1357 int i, rv = 0;
1358
1359 for (i = 0; i < minor_count; i++) {
1360 odev = minor_to_mdev(i);
1361 if (!odev)
1362 continue;
1363 if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS)
1364 continue;
1365 if (!_drbd_may_sync_now(odev))
1366 rv |= (__drbd_set_state(_NS(odev, aftr_isp, 1), CS_HARD, NULL)
1367 != SS_NOTHING_TO_DO);
1368 }
1369
1370 return rv;
1371}
1372
1373/**
1374 * _drbd_resume_next() - Resume resync on all devices that may resync now
1375 * @mdev: DRBD device.
1376 *
1377 * Called from process context only (admin command and worker).
1378 */
1379static int _drbd_resume_next(struct drbd_conf *mdev)
1380{
1381 struct drbd_conf *odev;
1382 int i, rv = 0;
1383
1384 for (i = 0; i < minor_count; i++) {
1385 odev = minor_to_mdev(i);
1386 if (!odev)
1387 continue;
1388 if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS)
1389 continue;
1390 if (odev->state.aftr_isp) {
1391 if (_drbd_may_sync_now(odev))
1392 rv |= (__drbd_set_state(_NS(odev, aftr_isp, 0),
1393 CS_HARD, NULL)
1394 != SS_NOTHING_TO_DO) ;
1395 }
1396 }
1397 return rv;
1398}
1399
1400void resume_next_sg(struct drbd_conf *mdev)
1401{
1402 write_lock_irq(&global_state_lock);
1403 _drbd_resume_next(mdev);
1404 write_unlock_irq(&global_state_lock);
1405}
1406
1407void suspend_other_sg(struct drbd_conf *mdev)
1408{
1409 write_lock_irq(&global_state_lock);
1410 _drbd_pause_after(mdev);
1411 write_unlock_irq(&global_state_lock);
1412}
1413
1414static int sync_after_error(struct drbd_conf *mdev, int o_minor)
1415{
1416 struct drbd_conf *odev;
1417
1418 if (o_minor == -1)
1419 return NO_ERROR;
1420 if (o_minor < -1 || minor_to_mdev(o_minor) == NULL)
1421 return ERR_SYNC_AFTER;
1422
1423 /* check for loops */
1424 odev = minor_to_mdev(o_minor);
1425 while (1) {
1426 if (odev == mdev)
1427 return ERR_SYNC_AFTER_CYCLE;
1428
1429 /* dependency chain ends here, no cycles. */
1430 if (odev->sync_conf.after == -1)
1431 return NO_ERROR;
1432
1433 /* follow the dependency chain */
1434 odev = minor_to_mdev(odev->sync_conf.after);
1435 }
1436}
1437
1438int drbd_alter_sa(struct drbd_conf *mdev, int na)
1439{
1440 int changes;
1441 int retcode;
1442
1443 write_lock_irq(&global_state_lock);
1444 retcode = sync_after_error(mdev, na);
1445 if (retcode == NO_ERROR) {
1446 mdev->sync_conf.after = na;
1447 do {
1448 changes = _drbd_pause_after(mdev);
1449 changes |= _drbd_resume_next(mdev);
1450 } while (changes);
1451 }
1452 write_unlock_irq(&global_state_lock);
1453 return retcode;
1454}
1455
1456void drbd_rs_controller_reset(struct drbd_conf *mdev)
1457{
1458 atomic_set(&mdev->rs_sect_in, 0);
1459 atomic_set(&mdev->rs_sect_ev, 0);
1460 mdev->rs_in_flight = 0;
1461 mdev->rs_planed = 0;
1462 spin_lock(&mdev->peer_seq_lock);
1463 fifo_set(&mdev->rs_plan_s, 0);
1464 spin_unlock(&mdev->peer_seq_lock);
1465}
1466
1467/**
1468 * drbd_start_resync() - Start the resync process
1469 * @mdev: DRBD device.
1470 * @side: Either C_SYNC_SOURCE or C_SYNC_TARGET
1471 *
1472 * This function might bring you directly into one of the
1473 * C_PAUSED_SYNC_* states.
1474 */
1475void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side)
1476{
1477 union drbd_state ns;
1478 int r;
1479
1480 if (mdev->state.conn >= C_SYNC_SOURCE && mdev->state.conn < C_AHEAD) {
1481 dev_err(DEV, "Resync already running!\n");
1482 return;
1483 }
1484
1485 if (mdev->state.conn < C_AHEAD) {
1486 /* In case a previous resync run was aborted by an IO error/detach on the peer. */
1487 drbd_rs_cancel_all(mdev);
1488 /* This should be done when we abort the resync. We definitely do not
1489 want to have this for connections going back and forth between
1490 Ahead/Behind and SyncSource/SyncTarget */
1491 }
1492
1493 if (side == C_SYNC_TARGET) {
1494 /* Since application IO was locked out during C_WF_BITMAP_T and
1495 C_WF_SYNC_UUID we are still unmodified. Before going to C_SYNC_TARGET
1496 we check that we might make the data inconsistent. */
1497 r = drbd_khelper(mdev, "before-resync-target");
1498 r = (r >> 8) & 0xff;
1499 if (r > 0) {
1500 dev_info(DEV, "before-resync-target handler returned %d, "
1501 "dropping connection.\n", r);
1502 drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
1503 return;
1504 }
1505 } else /* C_SYNC_SOURCE */ {
1506 r = drbd_khelper(mdev, "before-resync-source");
1507 r = (r >> 8) & 0xff;
1508 if (r > 0) {
1509 if (r == 3) {
1510 dev_info(DEV, "before-resync-source handler returned %d, "
1511 "ignoring. Old userland tools?", r);
1512 } else {
1513 dev_info(DEV, "before-resync-source handler returned %d, "
1514 "dropping connection.\n", r);
1515 drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
1516 return;
1517 }
1518 }
1519 }
1520
1521 drbd_state_lock(mdev);
1522
1523 if (!get_ldev_if_state(mdev, D_NEGOTIATING)) {
1524 drbd_state_unlock(mdev);
1525 return;
1526 }
1527
1528 write_lock_irq(&global_state_lock);
1529 ns = mdev->state;
1530
1531 ns.aftr_isp = !_drbd_may_sync_now(mdev);
1532
1533 ns.conn = side;
1534
1535 if (side == C_SYNC_TARGET)
1536 ns.disk = D_INCONSISTENT;
1537 else /* side == C_SYNC_SOURCE */
1538 ns.pdsk = D_INCONSISTENT;
1539
1540 r = __drbd_set_state(mdev, ns, CS_VERBOSE, NULL);
1541 ns = mdev->state;
1542
1543 if (ns.conn < C_CONNECTED)
1544 r = SS_UNKNOWN_ERROR;
1545
1546 if (r == SS_SUCCESS) {
1547 unsigned long tw = drbd_bm_total_weight(mdev);
1548 unsigned long now = jiffies;
1549 int i;
1550
1551 mdev->rs_failed = 0;
1552 mdev->rs_paused = 0;
1553 mdev->rs_same_csum = 0;
1554 mdev->rs_last_events = 0;
1555 mdev->rs_last_sect_ev = 0;
1556 mdev->rs_total = tw;
1557 mdev->rs_start = now;
1558 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
1559 mdev->rs_mark_left[i] = tw;
1560 mdev->rs_mark_time[i] = now;
1561 }
1562 _drbd_pause_after(mdev);
1563 }
1564 write_unlock_irq(&global_state_lock);
1565
1566 if (r == SS_SUCCESS) {
1567 dev_info(DEV, "Began resync as %s (will sync %lu KB [%lu bits set]).\n",
1568 drbd_conn_str(ns.conn),
1569 (unsigned long) mdev->rs_total << (BM_BLOCK_SHIFT-10),
1570 (unsigned long) mdev->rs_total);
1571 if (side == C_SYNC_TARGET)
1572 mdev->bm_resync_fo = 0;
1573
1574 /* Since protocol 96, we must serialize drbd_gen_and_send_sync_uuid
1575 * with w_send_oos, or the sync target will get confused as to
1576 * how much bits to resync. We cannot do that always, because for an
1577 * empty resync and protocol < 95, we need to do it here, as we call
1578 * drbd_resync_finished from here in that case.
1579 * We drbd_gen_and_send_sync_uuid here for protocol < 96,
1580 * and from after_state_ch otherwise. */
1581 if (side == C_SYNC_SOURCE && mdev->agreed_pro_version < 96)
1582 drbd_gen_and_send_sync_uuid(mdev);
1583
1584 if (mdev->agreed_pro_version < 95 && mdev->rs_total == 0) {
1585 /* This still has a race (about when exactly the peers
1586 * detect connection loss) that can lead to a full sync
1587 * on next handshake. In 8.3.9 we fixed this with explicit
1588 * resync-finished notifications, but the fix
1589 * introduces a protocol change. Sleeping for some
1590 * time longer than the ping interval + timeout on the
1591 * SyncSource, to give the SyncTarget the chance to
1592 * detect connection loss, then waiting for a ping
1593 * response (implicit in drbd_resync_finished) reduces
1594 * the race considerably, but does not solve it. */
1595 if (side == C_SYNC_SOURCE)
1596 schedule_timeout_interruptible(
1597 mdev->net_conf->ping_int * HZ +
1598 mdev->net_conf->ping_timeo*HZ/9);
1599 drbd_resync_finished(mdev);
1600 }
1601
1602 drbd_rs_controller_reset(mdev);
1603 /* ns.conn may already be != mdev->state.conn,
1604 * we may have been paused in between, or become paused until
1605 * the timer triggers.
1606 * No matter, that is handled in resync_timer_fn() */
1607 if (ns.conn == C_SYNC_TARGET)
1608 mod_timer(&mdev->resync_timer, jiffies);
1609
1610 drbd_md_sync(mdev);
1611 }
1612 put_ldev(mdev);
1613 drbd_state_unlock(mdev);
1614}
1615
1616int drbd_worker(struct drbd_thread *thi)
1617{
1618 struct drbd_conf *mdev = thi->mdev;
1619 struct drbd_work *w = NULL;
1620 LIST_HEAD(work_list);
1621 int intr = 0, i;
1622
1623 sprintf(current->comm, "drbd%d_worker", mdev_to_minor(mdev));
1624
1625 while (get_t_state(thi) == Running) {
1626 drbd_thread_current_set_cpu(mdev);
1627
1628 if (down_trylock(&mdev->data.work.s)) {
1629 mutex_lock(&mdev->data.mutex);
1630 if (mdev->data.socket && !mdev->net_conf->no_cork)
1631 drbd_tcp_uncork(mdev->data.socket);
1632 mutex_unlock(&mdev->data.mutex);
1633
1634 intr = down_interruptible(&mdev->data.work.s);
1635
1636 mutex_lock(&mdev->data.mutex);
1637 if (mdev->data.socket && !mdev->net_conf->no_cork)
1638 drbd_tcp_cork(mdev->data.socket);
1639 mutex_unlock(&mdev->data.mutex);
1640 }
1641
1642 if (intr) {
1643 D_ASSERT(intr == -EINTR);
1644 flush_signals(current);
1645 ERR_IF (get_t_state(thi) == Running)
1646 continue;
1647 break;
1648 }
1649
1650 if (get_t_state(thi) != Running)
1651 break;
1652 /* With this break, we have done a down() but not consumed
1653 the entry from the list. The cleanup code takes care of
1654 this... */
1655
1656 w = NULL;
1657 spin_lock_irq(&mdev->data.work.q_lock);
1658 ERR_IF(list_empty(&mdev->data.work.q)) {
1659 /* something terribly wrong in our logic.
1660 * we were able to down() the semaphore,
1661 * but the list is empty... doh.
1662 *
1663 * what is the best thing to do now?
1664 * try again from scratch, restarting the receiver,
1665 * asender, whatnot? could break even more ugly,
1666 * e.g. when we are primary, but no good local data.
1667 *
1668 * I'll try to get away just starting over this loop.
1669 */
1670 spin_unlock_irq(&mdev->data.work.q_lock);
1671 continue;
1672 }
1673 w = list_entry(mdev->data.work.q.next, struct drbd_work, list);
1674 list_del_init(&w->list);
1675 spin_unlock_irq(&mdev->data.work.q_lock);
1676
1677 if (!w->cb(mdev, w, mdev->state.conn < C_CONNECTED)) {
1678 /* dev_warn(DEV, "worker: a callback failed! \n"); */
1679 if (mdev->state.conn >= C_CONNECTED)
1680 drbd_force_state(mdev,
1681 NS(conn, C_NETWORK_FAILURE));
1682 }
1683 }
1684 D_ASSERT(test_bit(DEVICE_DYING, &mdev->flags));
1685 D_ASSERT(test_bit(CONFIG_PENDING, &mdev->flags));
1686
1687 spin_lock_irq(&mdev->data.work.q_lock);
1688 i = 0;
1689 while (!list_empty(&mdev->data.work.q)) {
1690 list_splice_init(&mdev->data.work.q, &work_list);
1691 spin_unlock_irq(&mdev->data.work.q_lock);
1692
1693 while (!list_empty(&work_list)) {
1694 w = list_entry(work_list.next, struct drbd_work, list);
1695 list_del_init(&w->list);
1696 w->cb(mdev, w, 1);
1697 i++; /* dead debugging code */
1698 }
1699
1700 spin_lock_irq(&mdev->data.work.q_lock);
1701 }
1702 sema_init(&mdev->data.work.s, 0);
1703 /* DANGEROUS race: if someone did queue his work within the spinlock,
1704 * but up() ed outside the spinlock, we could get an up() on the
1705 * semaphore without corresponding list entry.
1706 * So don't do that.
1707 */
1708 spin_unlock_irq(&mdev->data.work.q_lock);
1709
1710 D_ASSERT(mdev->state.disk == D_DISKLESS && mdev->state.conn == C_STANDALONE);
1711 /* _drbd_set_state only uses stop_nowait.
1712 * wait here for the Exiting receiver. */
1713 drbd_thread_stop(&mdev->receiver);
1714 drbd_mdev_cleanup(mdev);
1715
1716 dev_info(DEV, "worker terminated\n");
1717
1718 clear_bit(DEVICE_DYING, &mdev->flags);
1719 clear_bit(CONFIG_PENDING, &mdev->flags);
1720 wake_up(&mdev->state_wait);
1721
1722 return 0;
1723}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 drbd_worker.c
4
5 This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
6
7 Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
8 Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>.
9 Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.
10
11
12*/
13
14#include <linux/module.h>
15#include <linux/drbd.h>
16#include <linux/sched/signal.h>
17#include <linux/wait.h>
18#include <linux/mm.h>
19#include <linux/memcontrol.h>
20#include <linux/mm_inline.h>
21#include <linux/slab.h>
22#include <linux/random.h>
23#include <linux/string.h>
24#include <linux/scatterlist.h>
25
26#include "drbd_int.h"
27#include "drbd_protocol.h"
28#include "drbd_req.h"
29
30static int make_ov_request(struct drbd_device *, int);
31static int make_resync_request(struct drbd_device *, int);
32
33/* endio handlers:
34 * drbd_md_endio (defined here)
35 * drbd_request_endio (defined here)
36 * drbd_peer_request_endio (defined here)
37 * drbd_bm_endio (defined in drbd_bitmap.c)
38 *
39 * For all these callbacks, note the following:
40 * The callbacks will be called in irq context by the IDE drivers,
41 * and in Softirqs/Tasklets/BH context by the SCSI drivers.
42 * Try to get the locking right :)
43 *
44 */
45
46/* used for synchronous meta data and bitmap IO
47 * submitted by drbd_md_sync_page_io()
48 */
49void drbd_md_endio(struct bio *bio)
50{
51 struct drbd_device *device;
52
53 device = bio->bi_private;
54 device->md_io.error = blk_status_to_errno(bio->bi_status);
55
56 /* special case: drbd_md_read() during drbd_adm_attach() */
57 if (device->ldev)
58 put_ldev(device);
59 bio_put(bio);
60
61 /* We grabbed an extra reference in _drbd_md_sync_page_io() to be able
62 * to timeout on the lower level device, and eventually detach from it.
63 * If this io completion runs after that timeout expired, this
64 * drbd_md_put_buffer() may allow us to finally try and re-attach.
65 * During normal operation, this only puts that extra reference
66 * down to 1 again.
67 * Make sure we first drop the reference, and only then signal
68 * completion, or we may (in drbd_al_read_log()) cycle so fast into the
69 * next drbd_md_sync_page_io(), that we trigger the
70 * ASSERT(atomic_read(&device->md_io_in_use) == 1) there.
71 */
72 drbd_md_put_buffer(device);
73 device->md_io.done = 1;
74 wake_up(&device->misc_wait);
75}
76
77/* reads on behalf of the partner,
78 * "submitted" by the receiver
79 */
80static void drbd_endio_read_sec_final(struct drbd_peer_request *peer_req) __releases(local)
81{
82 unsigned long flags = 0;
83 struct drbd_peer_device *peer_device = peer_req->peer_device;
84 struct drbd_device *device = peer_device->device;
85
86 spin_lock_irqsave(&device->resource->req_lock, flags);
87 device->read_cnt += peer_req->i.size >> 9;
88 list_del(&peer_req->w.list);
89 if (list_empty(&device->read_ee))
90 wake_up(&device->ee_wait);
91 if (test_bit(__EE_WAS_ERROR, &peer_req->flags))
92 __drbd_chk_io_error(device, DRBD_READ_ERROR);
93 spin_unlock_irqrestore(&device->resource->req_lock, flags);
94
95 drbd_queue_work(&peer_device->connection->sender_work, &peer_req->w);
96 put_ldev(device);
97}
98
99/* writes on behalf of the partner, or resync writes,
100 * "submitted" by the receiver, final stage. */
101void drbd_endio_write_sec_final(struct drbd_peer_request *peer_req) __releases(local)
102{
103 unsigned long flags = 0;
104 struct drbd_peer_device *peer_device = peer_req->peer_device;
105 struct drbd_device *device = peer_device->device;
106 struct drbd_connection *connection = peer_device->connection;
107 struct drbd_interval i;
108 int do_wake;
109 u64 block_id;
110 int do_al_complete_io;
111
112 /* after we moved peer_req to done_ee,
113 * we may no longer access it,
114 * it may be freed/reused already!
115 * (as soon as we release the req_lock) */
116 i = peer_req->i;
117 do_al_complete_io = peer_req->flags & EE_CALL_AL_COMPLETE_IO;
118 block_id = peer_req->block_id;
119 peer_req->flags &= ~EE_CALL_AL_COMPLETE_IO;
120
121 if (peer_req->flags & EE_WAS_ERROR) {
122 /* In protocol != C, we usually do not send write acks.
123 * In case of a write error, send the neg ack anyways. */
124 if (!__test_and_set_bit(__EE_SEND_WRITE_ACK, &peer_req->flags))
125 inc_unacked(device);
126 drbd_set_out_of_sync(device, peer_req->i.sector, peer_req->i.size);
127 }
128
129 spin_lock_irqsave(&device->resource->req_lock, flags);
130 device->writ_cnt += peer_req->i.size >> 9;
131 list_move_tail(&peer_req->w.list, &device->done_ee);
132
133 /*
134 * Do not remove from the write_requests tree here: we did not send the
135 * Ack yet and did not wake possibly waiting conflicting requests.
136 * Removed from the tree from "drbd_process_done_ee" within the
137 * appropriate dw.cb (e_end_block/e_end_resync_block) or from
138 * _drbd_clear_done_ee.
139 */
140
141 do_wake = list_empty(block_id == ID_SYNCER ? &device->sync_ee : &device->active_ee);
142
143 /* FIXME do we want to detach for failed REQ_OP_DISCARD?
144 * ((peer_req->flags & (EE_WAS_ERROR|EE_TRIM)) == EE_WAS_ERROR) */
145 if (peer_req->flags & EE_WAS_ERROR)
146 __drbd_chk_io_error(device, DRBD_WRITE_ERROR);
147
148 if (connection->cstate >= C_WF_REPORT_PARAMS) {
149 kref_get(&device->kref); /* put is in drbd_send_acks_wf() */
150 if (!queue_work(connection->ack_sender, &peer_device->send_acks_work))
151 kref_put(&device->kref, drbd_destroy_device);
152 }
153 spin_unlock_irqrestore(&device->resource->req_lock, flags);
154
155 if (block_id == ID_SYNCER)
156 drbd_rs_complete_io(device, i.sector);
157
158 if (do_wake)
159 wake_up(&device->ee_wait);
160
161 if (do_al_complete_io)
162 drbd_al_complete_io(device, &i);
163
164 put_ldev(device);
165}
166
167/* writes on behalf of the partner, or resync writes,
168 * "submitted" by the receiver.
169 */
170void drbd_peer_request_endio(struct bio *bio)
171{
172 struct drbd_peer_request *peer_req = bio->bi_private;
173 struct drbd_device *device = peer_req->peer_device->device;
174 bool is_write = bio_data_dir(bio) == WRITE;
175 bool is_discard = bio_op(bio) == REQ_OP_WRITE_ZEROES ||
176 bio_op(bio) == REQ_OP_DISCARD;
177
178 if (bio->bi_status && __ratelimit(&drbd_ratelimit_state))
179 drbd_warn(device, "%s: error=%d s=%llus\n",
180 is_write ? (is_discard ? "discard" : "write")
181 : "read", bio->bi_status,
182 (unsigned long long)peer_req->i.sector);
183
184 if (bio->bi_status)
185 set_bit(__EE_WAS_ERROR, &peer_req->flags);
186
187 bio_put(bio); /* no need for the bio anymore */
188 if (atomic_dec_and_test(&peer_req->pending_bios)) {
189 if (is_write)
190 drbd_endio_write_sec_final(peer_req);
191 else
192 drbd_endio_read_sec_final(peer_req);
193 }
194}
195
196static void
197drbd_panic_after_delayed_completion_of_aborted_request(struct drbd_device *device)
198{
199 panic("drbd%u %s/%u potential random memory corruption caused by delayed completion of aborted local request\n",
200 device->minor, device->resource->name, device->vnr);
201}
202
203/* read, readA or write requests on R_PRIMARY coming from drbd_make_request
204 */
205void drbd_request_endio(struct bio *bio)
206{
207 unsigned long flags;
208 struct drbd_request *req = bio->bi_private;
209 struct drbd_device *device = req->device;
210 struct bio_and_error m;
211 enum drbd_req_event what;
212
213 /* If this request was aborted locally before,
214 * but now was completed "successfully",
215 * chances are that this caused arbitrary data corruption.
216 *
217 * "aborting" requests, or force-detaching the disk, is intended for
218 * completely blocked/hung local backing devices which do no longer
219 * complete requests at all, not even do error completions. In this
220 * situation, usually a hard-reset and failover is the only way out.
221 *
222 * By "aborting", basically faking a local error-completion,
223 * we allow for a more graceful swichover by cleanly migrating services.
224 * Still the affected node has to be rebooted "soon".
225 *
226 * By completing these requests, we allow the upper layers to re-use
227 * the associated data pages.
228 *
229 * If later the local backing device "recovers", and now DMAs some data
230 * from disk into the original request pages, in the best case it will
231 * just put random data into unused pages; but typically it will corrupt
232 * meanwhile completely unrelated data, causing all sorts of damage.
233 *
234 * Which means delayed successful completion,
235 * especially for READ requests,
236 * is a reason to panic().
237 *
238 * We assume that a delayed *error* completion is OK,
239 * though we still will complain noisily about it.
240 */
241 if (unlikely(req->rq_state & RQ_LOCAL_ABORTED)) {
242 if (__ratelimit(&drbd_ratelimit_state))
243 drbd_emerg(device, "delayed completion of aborted local request; disk-timeout may be too aggressive\n");
244
245 if (!bio->bi_status)
246 drbd_panic_after_delayed_completion_of_aborted_request(device);
247 }
248
249 /* to avoid recursion in __req_mod */
250 if (unlikely(bio->bi_status)) {
251 switch (bio_op(bio)) {
252 case REQ_OP_WRITE_ZEROES:
253 case REQ_OP_DISCARD:
254 if (bio->bi_status == BLK_STS_NOTSUPP)
255 what = DISCARD_COMPLETED_NOTSUPP;
256 else
257 what = DISCARD_COMPLETED_WITH_ERROR;
258 break;
259 case REQ_OP_READ:
260 if (bio->bi_opf & REQ_RAHEAD)
261 what = READ_AHEAD_COMPLETED_WITH_ERROR;
262 else
263 what = READ_COMPLETED_WITH_ERROR;
264 break;
265 default:
266 what = WRITE_COMPLETED_WITH_ERROR;
267 break;
268 }
269 } else {
270 what = COMPLETED_OK;
271 }
272
273 req->private_bio = ERR_PTR(blk_status_to_errno(bio->bi_status));
274 bio_put(bio);
275
276 /* not req_mod(), we need irqsave here! */
277 spin_lock_irqsave(&device->resource->req_lock, flags);
278 __req_mod(req, what, &m);
279 spin_unlock_irqrestore(&device->resource->req_lock, flags);
280 put_ldev(device);
281
282 if (m.bio)
283 complete_master_bio(device, &m);
284}
285
286void drbd_csum_ee(struct crypto_shash *tfm, struct drbd_peer_request *peer_req, void *digest)
287{
288 SHASH_DESC_ON_STACK(desc, tfm);
289 struct page *page = peer_req->pages;
290 struct page *tmp;
291 unsigned len;
292 void *src;
293
294 desc->tfm = tfm;
295
296 crypto_shash_init(desc);
297
298 src = kmap_atomic(page);
299 while ((tmp = page_chain_next(page))) {
300 /* all but the last page will be fully used */
301 crypto_shash_update(desc, src, PAGE_SIZE);
302 kunmap_atomic(src);
303 page = tmp;
304 src = kmap_atomic(page);
305 }
306 /* and now the last, possibly only partially used page */
307 len = peer_req->i.size & (PAGE_SIZE - 1);
308 crypto_shash_update(desc, src, len ?: PAGE_SIZE);
309 kunmap_atomic(src);
310
311 crypto_shash_final(desc, digest);
312 shash_desc_zero(desc);
313}
314
315void drbd_csum_bio(struct crypto_shash *tfm, struct bio *bio, void *digest)
316{
317 SHASH_DESC_ON_STACK(desc, tfm);
318 struct bio_vec bvec;
319 struct bvec_iter iter;
320
321 desc->tfm = tfm;
322
323 crypto_shash_init(desc);
324
325 bio_for_each_segment(bvec, bio, iter) {
326 u8 *src;
327
328 src = kmap_atomic(bvec.bv_page);
329 crypto_shash_update(desc, src + bvec.bv_offset, bvec.bv_len);
330 kunmap_atomic(src);
331
332 /* REQ_OP_WRITE_SAME has only one segment,
333 * checksum the payload only once. */
334 if (bio_op(bio) == REQ_OP_WRITE_SAME)
335 break;
336 }
337 crypto_shash_final(desc, digest);
338 shash_desc_zero(desc);
339}
340
341/* MAYBE merge common code with w_e_end_ov_req */
342static int w_e_send_csum(struct drbd_work *w, int cancel)
343{
344 struct drbd_peer_request *peer_req = container_of(w, struct drbd_peer_request, w);
345 struct drbd_peer_device *peer_device = peer_req->peer_device;
346 struct drbd_device *device = peer_device->device;
347 int digest_size;
348 void *digest;
349 int err = 0;
350
351 if (unlikely(cancel))
352 goto out;
353
354 if (unlikely((peer_req->flags & EE_WAS_ERROR) != 0))
355 goto out;
356
357 digest_size = crypto_shash_digestsize(peer_device->connection->csums_tfm);
358 digest = kmalloc(digest_size, GFP_NOIO);
359 if (digest) {
360 sector_t sector = peer_req->i.sector;
361 unsigned int size = peer_req->i.size;
362 drbd_csum_ee(peer_device->connection->csums_tfm, peer_req, digest);
363 /* Free peer_req and pages before send.
364 * In case we block on congestion, we could otherwise run into
365 * some distributed deadlock, if the other side blocks on
366 * congestion as well, because our receiver blocks in
367 * drbd_alloc_pages due to pp_in_use > max_buffers. */
368 drbd_free_peer_req(device, peer_req);
369 peer_req = NULL;
370 inc_rs_pending(device);
371 err = drbd_send_drequest_csum(peer_device, sector, size,
372 digest, digest_size,
373 P_CSUM_RS_REQUEST);
374 kfree(digest);
375 } else {
376 drbd_err(device, "kmalloc() of digest failed.\n");
377 err = -ENOMEM;
378 }
379
380out:
381 if (peer_req)
382 drbd_free_peer_req(device, peer_req);
383
384 if (unlikely(err))
385 drbd_err(device, "drbd_send_drequest(..., csum) failed\n");
386 return err;
387}
388
389#define GFP_TRY (__GFP_HIGHMEM | __GFP_NOWARN)
390
391static int read_for_csum(struct drbd_peer_device *peer_device, sector_t sector, int size)
392{
393 struct drbd_device *device = peer_device->device;
394 struct drbd_peer_request *peer_req;
395
396 if (!get_ldev(device))
397 return -EIO;
398
399 /* GFP_TRY, because if there is no memory available right now, this may
400 * be rescheduled for later. It is "only" background resync, after all. */
401 peer_req = drbd_alloc_peer_req(peer_device, ID_SYNCER /* unused */, sector,
402 size, size, GFP_TRY);
403 if (!peer_req)
404 goto defer;
405
406 peer_req->w.cb = w_e_send_csum;
407 spin_lock_irq(&device->resource->req_lock);
408 list_add_tail(&peer_req->w.list, &device->read_ee);
409 spin_unlock_irq(&device->resource->req_lock);
410
411 atomic_add(size >> 9, &device->rs_sect_ev);
412 if (drbd_submit_peer_request(device, peer_req, REQ_OP_READ, 0,
413 DRBD_FAULT_RS_RD) == 0)
414 return 0;
415
416 /* If it failed because of ENOMEM, retry should help. If it failed
417 * because bio_add_page failed (probably broken lower level driver),
418 * retry may or may not help.
419 * If it does not, you may need to force disconnect. */
420 spin_lock_irq(&device->resource->req_lock);
421 list_del(&peer_req->w.list);
422 spin_unlock_irq(&device->resource->req_lock);
423
424 drbd_free_peer_req(device, peer_req);
425defer:
426 put_ldev(device);
427 return -EAGAIN;
428}
429
430int w_resync_timer(struct drbd_work *w, int cancel)
431{
432 struct drbd_device *device =
433 container_of(w, struct drbd_device, resync_work);
434
435 switch (device->state.conn) {
436 case C_VERIFY_S:
437 make_ov_request(device, cancel);
438 break;
439 case C_SYNC_TARGET:
440 make_resync_request(device, cancel);
441 break;
442 }
443
444 return 0;
445}
446
447void resync_timer_fn(struct timer_list *t)
448{
449 struct drbd_device *device = from_timer(device, t, resync_timer);
450
451 drbd_queue_work_if_unqueued(
452 &first_peer_device(device)->connection->sender_work,
453 &device->resync_work);
454}
455
456static void fifo_set(struct fifo_buffer *fb, int value)
457{
458 int i;
459
460 for (i = 0; i < fb->size; i++)
461 fb->values[i] = value;
462}
463
464static int fifo_push(struct fifo_buffer *fb, int value)
465{
466 int ov;
467
468 ov = fb->values[fb->head_index];
469 fb->values[fb->head_index++] = value;
470
471 if (fb->head_index >= fb->size)
472 fb->head_index = 0;
473
474 return ov;
475}
476
477static void fifo_add_val(struct fifo_buffer *fb, int value)
478{
479 int i;
480
481 for (i = 0; i < fb->size; i++)
482 fb->values[i] += value;
483}
484
485struct fifo_buffer *fifo_alloc(int fifo_size)
486{
487 struct fifo_buffer *fb;
488
489 fb = kzalloc(sizeof(struct fifo_buffer) + sizeof(int) * fifo_size, GFP_NOIO);
490 if (!fb)
491 return NULL;
492
493 fb->head_index = 0;
494 fb->size = fifo_size;
495 fb->total = 0;
496
497 return fb;
498}
499
500static int drbd_rs_controller(struct drbd_device *device, unsigned int sect_in)
501{
502 struct disk_conf *dc;
503 unsigned int want; /* The number of sectors we want in-flight */
504 int req_sect; /* Number of sectors to request in this turn */
505 int correction; /* Number of sectors more we need in-flight */
506 int cps; /* correction per invocation of drbd_rs_controller() */
507 int steps; /* Number of time steps to plan ahead */
508 int curr_corr;
509 int max_sect;
510 struct fifo_buffer *plan;
511
512 dc = rcu_dereference(device->ldev->disk_conf);
513 plan = rcu_dereference(device->rs_plan_s);
514
515 steps = plan->size; /* (dc->c_plan_ahead * 10 * SLEEP_TIME) / HZ; */
516
517 if (device->rs_in_flight + sect_in == 0) { /* At start of resync */
518 want = ((dc->resync_rate * 2 * SLEEP_TIME) / HZ) * steps;
519 } else { /* normal path */
520 want = dc->c_fill_target ? dc->c_fill_target :
521 sect_in * dc->c_delay_target * HZ / (SLEEP_TIME * 10);
522 }
523
524 correction = want - device->rs_in_flight - plan->total;
525
526 /* Plan ahead */
527 cps = correction / steps;
528 fifo_add_val(plan, cps);
529 plan->total += cps * steps;
530
531 /* What we do in this step */
532 curr_corr = fifo_push(plan, 0);
533 plan->total -= curr_corr;
534
535 req_sect = sect_in + curr_corr;
536 if (req_sect < 0)
537 req_sect = 0;
538
539 max_sect = (dc->c_max_rate * 2 * SLEEP_TIME) / HZ;
540 if (req_sect > max_sect)
541 req_sect = max_sect;
542
543 /*
544 drbd_warn(device, "si=%u if=%d wa=%u co=%d st=%d cps=%d pl=%d cc=%d rs=%d\n",
545 sect_in, device->rs_in_flight, want, correction,
546 steps, cps, device->rs_planed, curr_corr, req_sect);
547 */
548
549 return req_sect;
550}
551
552static int drbd_rs_number_requests(struct drbd_device *device)
553{
554 unsigned int sect_in; /* Number of sectors that came in since the last turn */
555 int number, mxb;
556
557 sect_in = atomic_xchg(&device->rs_sect_in, 0);
558 device->rs_in_flight -= sect_in;
559
560 rcu_read_lock();
561 mxb = drbd_get_max_buffers(device) / 2;
562 if (rcu_dereference(device->rs_plan_s)->size) {
563 number = drbd_rs_controller(device, sect_in) >> (BM_BLOCK_SHIFT - 9);
564 device->c_sync_rate = number * HZ * (BM_BLOCK_SIZE / 1024) / SLEEP_TIME;
565 } else {
566 device->c_sync_rate = rcu_dereference(device->ldev->disk_conf)->resync_rate;
567 number = SLEEP_TIME * device->c_sync_rate / ((BM_BLOCK_SIZE / 1024) * HZ);
568 }
569 rcu_read_unlock();
570
571 /* Don't have more than "max-buffers"/2 in-flight.
572 * Otherwise we may cause the remote site to stall on drbd_alloc_pages(),
573 * potentially causing a distributed deadlock on congestion during
574 * online-verify or (checksum-based) resync, if max-buffers,
575 * socket buffer sizes and resync rate settings are mis-configured. */
576
577 /* note that "number" is in units of "BM_BLOCK_SIZE" (which is 4k),
578 * mxb (as used here, and in drbd_alloc_pages on the peer) is
579 * "number of pages" (typically also 4k),
580 * but "rs_in_flight" is in "sectors" (512 Byte). */
581 if (mxb - device->rs_in_flight/8 < number)
582 number = mxb - device->rs_in_flight/8;
583
584 return number;
585}
586
587static int make_resync_request(struct drbd_device *const device, int cancel)
588{
589 struct drbd_peer_device *const peer_device = first_peer_device(device);
590 struct drbd_connection *const connection = peer_device ? peer_device->connection : NULL;
591 unsigned long bit;
592 sector_t sector;
593 const sector_t capacity = drbd_get_capacity(device->this_bdev);
594 int max_bio_size;
595 int number, rollback_i, size;
596 int align, requeue = 0;
597 int i = 0;
598 int discard_granularity = 0;
599
600 if (unlikely(cancel))
601 return 0;
602
603 if (device->rs_total == 0) {
604 /* empty resync? */
605 drbd_resync_finished(device);
606 return 0;
607 }
608
609 if (!get_ldev(device)) {
610 /* Since we only need to access device->rsync a
611 get_ldev_if_state(device,D_FAILED) would be sufficient, but
612 to continue resync with a broken disk makes no sense at
613 all */
614 drbd_err(device, "Disk broke down during resync!\n");
615 return 0;
616 }
617
618 if (connection->agreed_features & DRBD_FF_THIN_RESYNC) {
619 rcu_read_lock();
620 discard_granularity = rcu_dereference(device->ldev->disk_conf)->rs_discard_granularity;
621 rcu_read_unlock();
622 }
623
624 max_bio_size = queue_max_hw_sectors(device->rq_queue) << 9;
625 number = drbd_rs_number_requests(device);
626 if (number <= 0)
627 goto requeue;
628
629 for (i = 0; i < number; i++) {
630 /* Stop generating RS requests when half of the send buffer is filled,
631 * but notify TCP that we'd like to have more space. */
632 mutex_lock(&connection->data.mutex);
633 if (connection->data.socket) {
634 struct sock *sk = connection->data.socket->sk;
635 int queued = sk->sk_wmem_queued;
636 int sndbuf = sk->sk_sndbuf;
637 if (queued > sndbuf / 2) {
638 requeue = 1;
639 if (sk->sk_socket)
640 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
641 }
642 } else
643 requeue = 1;
644 mutex_unlock(&connection->data.mutex);
645 if (requeue)
646 goto requeue;
647
648next_sector:
649 size = BM_BLOCK_SIZE;
650 bit = drbd_bm_find_next(device, device->bm_resync_fo);
651
652 if (bit == DRBD_END_OF_BITMAP) {
653 device->bm_resync_fo = drbd_bm_bits(device);
654 put_ldev(device);
655 return 0;
656 }
657
658 sector = BM_BIT_TO_SECT(bit);
659
660 if (drbd_try_rs_begin_io(device, sector)) {
661 device->bm_resync_fo = bit;
662 goto requeue;
663 }
664 device->bm_resync_fo = bit + 1;
665
666 if (unlikely(drbd_bm_test_bit(device, bit) == 0)) {
667 drbd_rs_complete_io(device, sector);
668 goto next_sector;
669 }
670
671#if DRBD_MAX_BIO_SIZE > BM_BLOCK_SIZE
672 /* try to find some adjacent bits.
673 * we stop if we have already the maximum req size.
674 *
675 * Additionally always align bigger requests, in order to
676 * be prepared for all stripe sizes of software RAIDs.
677 */
678 align = 1;
679 rollback_i = i;
680 while (i < number) {
681 if (size + BM_BLOCK_SIZE > max_bio_size)
682 break;
683
684 /* Be always aligned */
685 if (sector & ((1<<(align+3))-1))
686 break;
687
688 if (discard_granularity && size == discard_granularity)
689 break;
690
691 /* do not cross extent boundaries */
692 if (((bit+1) & BM_BLOCKS_PER_BM_EXT_MASK) == 0)
693 break;
694 /* now, is it actually dirty, after all?
695 * caution, drbd_bm_test_bit is tri-state for some
696 * obscure reason; ( b == 0 ) would get the out-of-band
697 * only accidentally right because of the "oddly sized"
698 * adjustment below */
699 if (drbd_bm_test_bit(device, bit+1) != 1)
700 break;
701 bit++;
702 size += BM_BLOCK_SIZE;
703 if ((BM_BLOCK_SIZE << align) <= size)
704 align++;
705 i++;
706 }
707 /* if we merged some,
708 * reset the offset to start the next drbd_bm_find_next from */
709 if (size > BM_BLOCK_SIZE)
710 device->bm_resync_fo = bit + 1;
711#endif
712
713 /* adjust very last sectors, in case we are oddly sized */
714 if (sector + (size>>9) > capacity)
715 size = (capacity-sector)<<9;
716
717 if (device->use_csums) {
718 switch (read_for_csum(peer_device, sector, size)) {
719 case -EIO: /* Disk failure */
720 put_ldev(device);
721 return -EIO;
722 case -EAGAIN: /* allocation failed, or ldev busy */
723 drbd_rs_complete_io(device, sector);
724 device->bm_resync_fo = BM_SECT_TO_BIT(sector);
725 i = rollback_i;
726 goto requeue;
727 case 0:
728 /* everything ok */
729 break;
730 default:
731 BUG();
732 }
733 } else {
734 int err;
735
736 inc_rs_pending(device);
737 err = drbd_send_drequest(peer_device,
738 size == discard_granularity ? P_RS_THIN_REQ : P_RS_DATA_REQUEST,
739 sector, size, ID_SYNCER);
740 if (err) {
741 drbd_err(device, "drbd_send_drequest() failed, aborting...\n");
742 dec_rs_pending(device);
743 put_ldev(device);
744 return err;
745 }
746 }
747 }
748
749 if (device->bm_resync_fo >= drbd_bm_bits(device)) {
750 /* last syncer _request_ was sent,
751 * but the P_RS_DATA_REPLY not yet received. sync will end (and
752 * next sync group will resume), as soon as we receive the last
753 * resync data block, and the last bit is cleared.
754 * until then resync "work" is "inactive" ...
755 */
756 put_ldev(device);
757 return 0;
758 }
759
760 requeue:
761 device->rs_in_flight += (i << (BM_BLOCK_SHIFT - 9));
762 mod_timer(&device->resync_timer, jiffies + SLEEP_TIME);
763 put_ldev(device);
764 return 0;
765}
766
767static int make_ov_request(struct drbd_device *device, int cancel)
768{
769 int number, i, size;
770 sector_t sector;
771 const sector_t capacity = drbd_get_capacity(device->this_bdev);
772 bool stop_sector_reached = false;
773
774 if (unlikely(cancel))
775 return 1;
776
777 number = drbd_rs_number_requests(device);
778
779 sector = device->ov_position;
780 for (i = 0; i < number; i++) {
781 if (sector >= capacity)
782 return 1;
783
784 /* We check for "finished" only in the reply path:
785 * w_e_end_ov_reply().
786 * We need to send at least one request out. */
787 stop_sector_reached = i > 0
788 && verify_can_do_stop_sector(device)
789 && sector >= device->ov_stop_sector;
790 if (stop_sector_reached)
791 break;
792
793 size = BM_BLOCK_SIZE;
794
795 if (drbd_try_rs_begin_io(device, sector)) {
796 device->ov_position = sector;
797 goto requeue;
798 }
799
800 if (sector + (size>>9) > capacity)
801 size = (capacity-sector)<<9;
802
803 inc_rs_pending(device);
804 if (drbd_send_ov_request(first_peer_device(device), sector, size)) {
805 dec_rs_pending(device);
806 return 0;
807 }
808 sector += BM_SECT_PER_BIT;
809 }
810 device->ov_position = sector;
811
812 requeue:
813 device->rs_in_flight += (i << (BM_BLOCK_SHIFT - 9));
814 if (i == 0 || !stop_sector_reached)
815 mod_timer(&device->resync_timer, jiffies + SLEEP_TIME);
816 return 1;
817}
818
819int w_ov_finished(struct drbd_work *w, int cancel)
820{
821 struct drbd_device_work *dw =
822 container_of(w, struct drbd_device_work, w);
823 struct drbd_device *device = dw->device;
824 kfree(dw);
825 ov_out_of_sync_print(device);
826 drbd_resync_finished(device);
827
828 return 0;
829}
830
831static int w_resync_finished(struct drbd_work *w, int cancel)
832{
833 struct drbd_device_work *dw =
834 container_of(w, struct drbd_device_work, w);
835 struct drbd_device *device = dw->device;
836 kfree(dw);
837
838 drbd_resync_finished(device);
839
840 return 0;
841}
842
843static void ping_peer(struct drbd_device *device)
844{
845 struct drbd_connection *connection = first_peer_device(device)->connection;
846
847 clear_bit(GOT_PING_ACK, &connection->flags);
848 request_ping(connection);
849 wait_event(connection->ping_wait,
850 test_bit(GOT_PING_ACK, &connection->flags) || device->state.conn < C_CONNECTED);
851}
852
853int drbd_resync_finished(struct drbd_device *device)
854{
855 struct drbd_connection *connection = first_peer_device(device)->connection;
856 unsigned long db, dt, dbdt;
857 unsigned long n_oos;
858 union drbd_state os, ns;
859 struct drbd_device_work *dw;
860 char *khelper_cmd = NULL;
861 int verify_done = 0;
862
863 /* Remove all elements from the resync LRU. Since future actions
864 * might set bits in the (main) bitmap, then the entries in the
865 * resync LRU would be wrong. */
866 if (drbd_rs_del_all(device)) {
867 /* In case this is not possible now, most probably because
868 * there are P_RS_DATA_REPLY Packets lingering on the worker's
869 * queue (or even the read operations for those packets
870 * is not finished by now). Retry in 100ms. */
871
872 schedule_timeout_interruptible(HZ / 10);
873 dw = kmalloc(sizeof(struct drbd_device_work), GFP_ATOMIC);
874 if (dw) {
875 dw->w.cb = w_resync_finished;
876 dw->device = device;
877 drbd_queue_work(&connection->sender_work, &dw->w);
878 return 1;
879 }
880 drbd_err(device, "Warn failed to drbd_rs_del_all() and to kmalloc(dw).\n");
881 }
882
883 dt = (jiffies - device->rs_start - device->rs_paused) / HZ;
884 if (dt <= 0)
885 dt = 1;
886
887 db = device->rs_total;
888 /* adjust for verify start and stop sectors, respective reached position */
889 if (device->state.conn == C_VERIFY_S || device->state.conn == C_VERIFY_T)
890 db -= device->ov_left;
891
892 dbdt = Bit2KB(db/dt);
893 device->rs_paused /= HZ;
894
895 if (!get_ldev(device))
896 goto out;
897
898 ping_peer(device);
899
900 spin_lock_irq(&device->resource->req_lock);
901 os = drbd_read_state(device);
902
903 verify_done = (os.conn == C_VERIFY_S || os.conn == C_VERIFY_T);
904
905 /* This protects us against multiple calls (that can happen in the presence
906 of application IO), and against connectivity loss just before we arrive here. */
907 if (os.conn <= C_CONNECTED)
908 goto out_unlock;
909
910 ns = os;
911 ns.conn = C_CONNECTED;
912
913 drbd_info(device, "%s done (total %lu sec; paused %lu sec; %lu K/sec)\n",
914 verify_done ? "Online verify" : "Resync",
915 dt + device->rs_paused, device->rs_paused, dbdt);
916
917 n_oos = drbd_bm_total_weight(device);
918
919 if (os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) {
920 if (n_oos) {
921 drbd_alert(device, "Online verify found %lu %dk block out of sync!\n",
922 n_oos, Bit2KB(1));
923 khelper_cmd = "out-of-sync";
924 }
925 } else {
926 D_ASSERT(device, (n_oos - device->rs_failed) == 0);
927
928 if (os.conn == C_SYNC_TARGET || os.conn == C_PAUSED_SYNC_T)
929 khelper_cmd = "after-resync-target";
930
931 if (device->use_csums && device->rs_total) {
932 const unsigned long s = device->rs_same_csum;
933 const unsigned long t = device->rs_total;
934 const int ratio =
935 (t == 0) ? 0 :
936 (t < 100000) ? ((s*100)/t) : (s/(t/100));
937 drbd_info(device, "%u %% had equal checksums, eliminated: %luK; "
938 "transferred %luK total %luK\n",
939 ratio,
940 Bit2KB(device->rs_same_csum),
941 Bit2KB(device->rs_total - device->rs_same_csum),
942 Bit2KB(device->rs_total));
943 }
944 }
945
946 if (device->rs_failed) {
947 drbd_info(device, " %lu failed blocks\n", device->rs_failed);
948
949 if (os.conn == C_SYNC_TARGET || os.conn == C_PAUSED_SYNC_T) {
950 ns.disk = D_INCONSISTENT;
951 ns.pdsk = D_UP_TO_DATE;
952 } else {
953 ns.disk = D_UP_TO_DATE;
954 ns.pdsk = D_INCONSISTENT;
955 }
956 } else {
957 ns.disk = D_UP_TO_DATE;
958 ns.pdsk = D_UP_TO_DATE;
959
960 if (os.conn == C_SYNC_TARGET || os.conn == C_PAUSED_SYNC_T) {
961 if (device->p_uuid) {
962 int i;
963 for (i = UI_BITMAP ; i <= UI_HISTORY_END ; i++)
964 _drbd_uuid_set(device, i, device->p_uuid[i]);
965 drbd_uuid_set(device, UI_BITMAP, device->ldev->md.uuid[UI_CURRENT]);
966 _drbd_uuid_set(device, UI_CURRENT, device->p_uuid[UI_CURRENT]);
967 } else {
968 drbd_err(device, "device->p_uuid is NULL! BUG\n");
969 }
970 }
971
972 if (!(os.conn == C_VERIFY_S || os.conn == C_VERIFY_T)) {
973 /* for verify runs, we don't update uuids here,
974 * so there would be nothing to report. */
975 drbd_uuid_set_bm(device, 0UL);
976 drbd_print_uuids(device, "updated UUIDs");
977 if (device->p_uuid) {
978 /* Now the two UUID sets are equal, update what we
979 * know of the peer. */
980 int i;
981 for (i = UI_CURRENT ; i <= UI_HISTORY_END ; i++)
982 device->p_uuid[i] = device->ldev->md.uuid[i];
983 }
984 }
985 }
986
987 _drbd_set_state(device, ns, CS_VERBOSE, NULL);
988out_unlock:
989 spin_unlock_irq(&device->resource->req_lock);
990
991 /* If we have been sync source, and have an effective fencing-policy,
992 * once *all* volumes are back in sync, call "unfence". */
993 if (os.conn == C_SYNC_SOURCE) {
994 enum drbd_disk_state disk_state = D_MASK;
995 enum drbd_disk_state pdsk_state = D_MASK;
996 enum drbd_fencing_p fp = FP_DONT_CARE;
997
998 rcu_read_lock();
999 fp = rcu_dereference(device->ldev->disk_conf)->fencing;
1000 if (fp != FP_DONT_CARE) {
1001 struct drbd_peer_device *peer_device;
1002 int vnr;
1003 idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
1004 struct drbd_device *device = peer_device->device;
1005 disk_state = min_t(enum drbd_disk_state, disk_state, device->state.disk);
1006 pdsk_state = min_t(enum drbd_disk_state, pdsk_state, device->state.pdsk);
1007 }
1008 }
1009 rcu_read_unlock();
1010 if (disk_state == D_UP_TO_DATE && pdsk_state == D_UP_TO_DATE)
1011 conn_khelper(connection, "unfence-peer");
1012 }
1013
1014 put_ldev(device);
1015out:
1016 device->rs_total = 0;
1017 device->rs_failed = 0;
1018 device->rs_paused = 0;
1019
1020 /* reset start sector, if we reached end of device */
1021 if (verify_done && device->ov_left == 0)
1022 device->ov_start_sector = 0;
1023
1024 drbd_md_sync(device);
1025
1026 if (khelper_cmd)
1027 drbd_khelper(device, khelper_cmd);
1028
1029 return 1;
1030}
1031
1032/* helper */
1033static void move_to_net_ee_or_free(struct drbd_device *device, struct drbd_peer_request *peer_req)
1034{
1035 if (drbd_peer_req_has_active_page(peer_req)) {
1036 /* This might happen if sendpage() has not finished */
1037 int i = (peer_req->i.size + PAGE_SIZE -1) >> PAGE_SHIFT;
1038 atomic_add(i, &device->pp_in_use_by_net);
1039 atomic_sub(i, &device->pp_in_use);
1040 spin_lock_irq(&device->resource->req_lock);
1041 list_add_tail(&peer_req->w.list, &device->net_ee);
1042 spin_unlock_irq(&device->resource->req_lock);
1043 wake_up(&drbd_pp_wait);
1044 } else
1045 drbd_free_peer_req(device, peer_req);
1046}
1047
1048/**
1049 * w_e_end_data_req() - Worker callback, to send a P_DATA_REPLY packet in response to a P_DATA_REQUEST
1050 * @w: work object.
1051 * @cancel: The connection will be closed anyways
1052 */
1053int w_e_end_data_req(struct drbd_work *w, int cancel)
1054{
1055 struct drbd_peer_request *peer_req = container_of(w, struct drbd_peer_request, w);
1056 struct drbd_peer_device *peer_device = peer_req->peer_device;
1057 struct drbd_device *device = peer_device->device;
1058 int err;
1059
1060 if (unlikely(cancel)) {
1061 drbd_free_peer_req(device, peer_req);
1062 dec_unacked(device);
1063 return 0;
1064 }
1065
1066 if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) {
1067 err = drbd_send_block(peer_device, P_DATA_REPLY, peer_req);
1068 } else {
1069 if (__ratelimit(&drbd_ratelimit_state))
1070 drbd_err(device, "Sending NegDReply. sector=%llus.\n",
1071 (unsigned long long)peer_req->i.sector);
1072
1073 err = drbd_send_ack(peer_device, P_NEG_DREPLY, peer_req);
1074 }
1075
1076 dec_unacked(device);
1077
1078 move_to_net_ee_or_free(device, peer_req);
1079
1080 if (unlikely(err))
1081 drbd_err(device, "drbd_send_block() failed\n");
1082 return err;
1083}
1084
1085static bool all_zero(struct drbd_peer_request *peer_req)
1086{
1087 struct page *page = peer_req->pages;
1088 unsigned int len = peer_req->i.size;
1089
1090 page_chain_for_each(page) {
1091 unsigned int l = min_t(unsigned int, len, PAGE_SIZE);
1092 unsigned int i, words = l / sizeof(long);
1093 unsigned long *d;
1094
1095 d = kmap_atomic(page);
1096 for (i = 0; i < words; i++) {
1097 if (d[i]) {
1098 kunmap_atomic(d);
1099 return false;
1100 }
1101 }
1102 kunmap_atomic(d);
1103 len -= l;
1104 }
1105
1106 return true;
1107}
1108
1109/**
1110 * w_e_end_rsdata_req() - Worker callback to send a P_RS_DATA_REPLY packet in response to a P_RS_DATA_REQUEST
1111 * @w: work object.
1112 * @cancel: The connection will be closed anyways
1113 */
1114int w_e_end_rsdata_req(struct drbd_work *w, int cancel)
1115{
1116 struct drbd_peer_request *peer_req = container_of(w, struct drbd_peer_request, w);
1117 struct drbd_peer_device *peer_device = peer_req->peer_device;
1118 struct drbd_device *device = peer_device->device;
1119 int err;
1120
1121 if (unlikely(cancel)) {
1122 drbd_free_peer_req(device, peer_req);
1123 dec_unacked(device);
1124 return 0;
1125 }
1126
1127 if (get_ldev_if_state(device, D_FAILED)) {
1128 drbd_rs_complete_io(device, peer_req->i.sector);
1129 put_ldev(device);
1130 }
1131
1132 if (device->state.conn == C_AHEAD) {
1133 err = drbd_send_ack(peer_device, P_RS_CANCEL, peer_req);
1134 } else if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) {
1135 if (likely(device->state.pdsk >= D_INCONSISTENT)) {
1136 inc_rs_pending(device);
1137 if (peer_req->flags & EE_RS_THIN_REQ && all_zero(peer_req))
1138 err = drbd_send_rs_deallocated(peer_device, peer_req);
1139 else
1140 err = drbd_send_block(peer_device, P_RS_DATA_REPLY, peer_req);
1141 } else {
1142 if (__ratelimit(&drbd_ratelimit_state))
1143 drbd_err(device, "Not sending RSDataReply, "
1144 "partner DISKLESS!\n");
1145 err = 0;
1146 }
1147 } else {
1148 if (__ratelimit(&drbd_ratelimit_state))
1149 drbd_err(device, "Sending NegRSDReply. sector %llus.\n",
1150 (unsigned long long)peer_req->i.sector);
1151
1152 err = drbd_send_ack(peer_device, P_NEG_RS_DREPLY, peer_req);
1153
1154 /* update resync data with failure */
1155 drbd_rs_failed_io(device, peer_req->i.sector, peer_req->i.size);
1156 }
1157
1158 dec_unacked(device);
1159
1160 move_to_net_ee_or_free(device, peer_req);
1161
1162 if (unlikely(err))
1163 drbd_err(device, "drbd_send_block() failed\n");
1164 return err;
1165}
1166
1167int w_e_end_csum_rs_req(struct drbd_work *w, int cancel)
1168{
1169 struct drbd_peer_request *peer_req = container_of(w, struct drbd_peer_request, w);
1170 struct drbd_peer_device *peer_device = peer_req->peer_device;
1171 struct drbd_device *device = peer_device->device;
1172 struct digest_info *di;
1173 int digest_size;
1174 void *digest = NULL;
1175 int err, eq = 0;
1176
1177 if (unlikely(cancel)) {
1178 drbd_free_peer_req(device, peer_req);
1179 dec_unacked(device);
1180 return 0;
1181 }
1182
1183 if (get_ldev(device)) {
1184 drbd_rs_complete_io(device, peer_req->i.sector);
1185 put_ldev(device);
1186 }
1187
1188 di = peer_req->digest;
1189
1190 if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) {
1191 /* quick hack to try to avoid a race against reconfiguration.
1192 * a real fix would be much more involved,
1193 * introducing more locking mechanisms */
1194 if (peer_device->connection->csums_tfm) {
1195 digest_size = crypto_shash_digestsize(peer_device->connection->csums_tfm);
1196 D_ASSERT(device, digest_size == di->digest_size);
1197 digest = kmalloc(digest_size, GFP_NOIO);
1198 }
1199 if (digest) {
1200 drbd_csum_ee(peer_device->connection->csums_tfm, peer_req, digest);
1201 eq = !memcmp(digest, di->digest, digest_size);
1202 kfree(digest);
1203 }
1204
1205 if (eq) {
1206 drbd_set_in_sync(device, peer_req->i.sector, peer_req->i.size);
1207 /* rs_same_csums unit is BM_BLOCK_SIZE */
1208 device->rs_same_csum += peer_req->i.size >> BM_BLOCK_SHIFT;
1209 err = drbd_send_ack(peer_device, P_RS_IS_IN_SYNC, peer_req);
1210 } else {
1211 inc_rs_pending(device);
1212 peer_req->block_id = ID_SYNCER; /* By setting block_id, digest pointer becomes invalid! */
1213 peer_req->flags &= ~EE_HAS_DIGEST; /* This peer request no longer has a digest pointer */
1214 kfree(di);
1215 err = drbd_send_block(peer_device, P_RS_DATA_REPLY, peer_req);
1216 }
1217 } else {
1218 err = drbd_send_ack(peer_device, P_NEG_RS_DREPLY, peer_req);
1219 if (__ratelimit(&drbd_ratelimit_state))
1220 drbd_err(device, "Sending NegDReply. I guess it gets messy.\n");
1221 }
1222
1223 dec_unacked(device);
1224 move_to_net_ee_or_free(device, peer_req);
1225
1226 if (unlikely(err))
1227 drbd_err(device, "drbd_send_block/ack() failed\n");
1228 return err;
1229}
1230
1231int w_e_end_ov_req(struct drbd_work *w, int cancel)
1232{
1233 struct drbd_peer_request *peer_req = container_of(w, struct drbd_peer_request, w);
1234 struct drbd_peer_device *peer_device = peer_req->peer_device;
1235 struct drbd_device *device = peer_device->device;
1236 sector_t sector = peer_req->i.sector;
1237 unsigned int size = peer_req->i.size;
1238 int digest_size;
1239 void *digest;
1240 int err = 0;
1241
1242 if (unlikely(cancel))
1243 goto out;
1244
1245 digest_size = crypto_shash_digestsize(peer_device->connection->verify_tfm);
1246 digest = kmalloc(digest_size, GFP_NOIO);
1247 if (!digest) {
1248 err = 1; /* terminate the connection in case the allocation failed */
1249 goto out;
1250 }
1251
1252 if (likely(!(peer_req->flags & EE_WAS_ERROR)))
1253 drbd_csum_ee(peer_device->connection->verify_tfm, peer_req, digest);
1254 else
1255 memset(digest, 0, digest_size);
1256
1257 /* Free e and pages before send.
1258 * In case we block on congestion, we could otherwise run into
1259 * some distributed deadlock, if the other side blocks on
1260 * congestion as well, because our receiver blocks in
1261 * drbd_alloc_pages due to pp_in_use > max_buffers. */
1262 drbd_free_peer_req(device, peer_req);
1263 peer_req = NULL;
1264 inc_rs_pending(device);
1265 err = drbd_send_drequest_csum(peer_device, sector, size, digest, digest_size, P_OV_REPLY);
1266 if (err)
1267 dec_rs_pending(device);
1268 kfree(digest);
1269
1270out:
1271 if (peer_req)
1272 drbd_free_peer_req(device, peer_req);
1273 dec_unacked(device);
1274 return err;
1275}
1276
1277void drbd_ov_out_of_sync_found(struct drbd_device *device, sector_t sector, int size)
1278{
1279 if (device->ov_last_oos_start + device->ov_last_oos_size == sector) {
1280 device->ov_last_oos_size += size>>9;
1281 } else {
1282 device->ov_last_oos_start = sector;
1283 device->ov_last_oos_size = size>>9;
1284 }
1285 drbd_set_out_of_sync(device, sector, size);
1286}
1287
1288int w_e_end_ov_reply(struct drbd_work *w, int cancel)
1289{
1290 struct drbd_peer_request *peer_req = container_of(w, struct drbd_peer_request, w);
1291 struct drbd_peer_device *peer_device = peer_req->peer_device;
1292 struct drbd_device *device = peer_device->device;
1293 struct digest_info *di;
1294 void *digest;
1295 sector_t sector = peer_req->i.sector;
1296 unsigned int size = peer_req->i.size;
1297 int digest_size;
1298 int err, eq = 0;
1299 bool stop_sector_reached = false;
1300
1301 if (unlikely(cancel)) {
1302 drbd_free_peer_req(device, peer_req);
1303 dec_unacked(device);
1304 return 0;
1305 }
1306
1307 /* after "cancel", because after drbd_disconnect/drbd_rs_cancel_all
1308 * the resync lru has been cleaned up already */
1309 if (get_ldev(device)) {
1310 drbd_rs_complete_io(device, peer_req->i.sector);
1311 put_ldev(device);
1312 }
1313
1314 di = peer_req->digest;
1315
1316 if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) {
1317 digest_size = crypto_shash_digestsize(peer_device->connection->verify_tfm);
1318 digest = kmalloc(digest_size, GFP_NOIO);
1319 if (digest) {
1320 drbd_csum_ee(peer_device->connection->verify_tfm, peer_req, digest);
1321
1322 D_ASSERT(device, digest_size == di->digest_size);
1323 eq = !memcmp(digest, di->digest, digest_size);
1324 kfree(digest);
1325 }
1326 }
1327
1328 /* Free peer_req and pages before send.
1329 * In case we block on congestion, we could otherwise run into
1330 * some distributed deadlock, if the other side blocks on
1331 * congestion as well, because our receiver blocks in
1332 * drbd_alloc_pages due to pp_in_use > max_buffers. */
1333 drbd_free_peer_req(device, peer_req);
1334 if (!eq)
1335 drbd_ov_out_of_sync_found(device, sector, size);
1336 else
1337 ov_out_of_sync_print(device);
1338
1339 err = drbd_send_ack_ex(peer_device, P_OV_RESULT, sector, size,
1340 eq ? ID_IN_SYNC : ID_OUT_OF_SYNC);
1341
1342 dec_unacked(device);
1343
1344 --device->ov_left;
1345
1346 /* let's advance progress step marks only for every other megabyte */
1347 if ((device->ov_left & 0x200) == 0x200)
1348 drbd_advance_rs_marks(device, device->ov_left);
1349
1350 stop_sector_reached = verify_can_do_stop_sector(device) &&
1351 (sector + (size>>9)) >= device->ov_stop_sector;
1352
1353 if (device->ov_left == 0 || stop_sector_reached) {
1354 ov_out_of_sync_print(device);
1355 drbd_resync_finished(device);
1356 }
1357
1358 return err;
1359}
1360
1361/* FIXME
1362 * We need to track the number of pending barrier acks,
1363 * and to be able to wait for them.
1364 * See also comment in drbd_adm_attach before drbd_suspend_io.
1365 */
1366static int drbd_send_barrier(struct drbd_connection *connection)
1367{
1368 struct p_barrier *p;
1369 struct drbd_socket *sock;
1370
1371 sock = &connection->data;
1372 p = conn_prepare_command(connection, sock);
1373 if (!p)
1374 return -EIO;
1375 p->barrier = connection->send.current_epoch_nr;
1376 p->pad = 0;
1377 connection->send.current_epoch_writes = 0;
1378 connection->send.last_sent_barrier_jif = jiffies;
1379
1380 return conn_send_command(connection, sock, P_BARRIER, sizeof(*p), NULL, 0);
1381}
1382
1383static int pd_send_unplug_remote(struct drbd_peer_device *pd)
1384{
1385 struct drbd_socket *sock = &pd->connection->data;
1386 if (!drbd_prepare_command(pd, sock))
1387 return -EIO;
1388 return drbd_send_command(pd, sock, P_UNPLUG_REMOTE, 0, NULL, 0);
1389}
1390
1391int w_send_write_hint(struct drbd_work *w, int cancel)
1392{
1393 struct drbd_device *device =
1394 container_of(w, struct drbd_device, unplug_work);
1395
1396 if (cancel)
1397 return 0;
1398 return pd_send_unplug_remote(first_peer_device(device));
1399}
1400
1401static void re_init_if_first_write(struct drbd_connection *connection, unsigned int epoch)
1402{
1403 if (!connection->send.seen_any_write_yet) {
1404 connection->send.seen_any_write_yet = true;
1405 connection->send.current_epoch_nr = epoch;
1406 connection->send.current_epoch_writes = 0;
1407 connection->send.last_sent_barrier_jif = jiffies;
1408 }
1409}
1410
1411static void maybe_send_barrier(struct drbd_connection *connection, unsigned int epoch)
1412{
1413 /* re-init if first write on this connection */
1414 if (!connection->send.seen_any_write_yet)
1415 return;
1416 if (connection->send.current_epoch_nr != epoch) {
1417 if (connection->send.current_epoch_writes)
1418 drbd_send_barrier(connection);
1419 connection->send.current_epoch_nr = epoch;
1420 }
1421}
1422
1423int w_send_out_of_sync(struct drbd_work *w, int cancel)
1424{
1425 struct drbd_request *req = container_of(w, struct drbd_request, w);
1426 struct drbd_device *device = req->device;
1427 struct drbd_peer_device *const peer_device = first_peer_device(device);
1428 struct drbd_connection *const connection = peer_device->connection;
1429 int err;
1430
1431 if (unlikely(cancel)) {
1432 req_mod(req, SEND_CANCELED);
1433 return 0;
1434 }
1435 req->pre_send_jif = jiffies;
1436
1437 /* this time, no connection->send.current_epoch_writes++;
1438 * If it was sent, it was the closing barrier for the last
1439 * replicated epoch, before we went into AHEAD mode.
1440 * No more barriers will be sent, until we leave AHEAD mode again. */
1441 maybe_send_barrier(connection, req->epoch);
1442
1443 err = drbd_send_out_of_sync(peer_device, req);
1444 req_mod(req, OOS_HANDED_TO_NETWORK);
1445
1446 return err;
1447}
1448
1449/**
1450 * w_send_dblock() - Worker callback to send a P_DATA packet in order to mirror a write request
1451 * @w: work object.
1452 * @cancel: The connection will be closed anyways
1453 */
1454int w_send_dblock(struct drbd_work *w, int cancel)
1455{
1456 struct drbd_request *req = container_of(w, struct drbd_request, w);
1457 struct drbd_device *device = req->device;
1458 struct drbd_peer_device *const peer_device = first_peer_device(device);
1459 struct drbd_connection *connection = peer_device->connection;
1460 bool do_send_unplug = req->rq_state & RQ_UNPLUG;
1461 int err;
1462
1463 if (unlikely(cancel)) {
1464 req_mod(req, SEND_CANCELED);
1465 return 0;
1466 }
1467 req->pre_send_jif = jiffies;
1468
1469 re_init_if_first_write(connection, req->epoch);
1470 maybe_send_barrier(connection, req->epoch);
1471 connection->send.current_epoch_writes++;
1472
1473 err = drbd_send_dblock(peer_device, req);
1474 req_mod(req, err ? SEND_FAILED : HANDED_OVER_TO_NETWORK);
1475
1476 if (do_send_unplug && !err)
1477 pd_send_unplug_remote(peer_device);
1478
1479 return err;
1480}
1481
1482/**
1483 * w_send_read_req() - Worker callback to send a read request (P_DATA_REQUEST) packet
1484 * @w: work object.
1485 * @cancel: The connection will be closed anyways
1486 */
1487int w_send_read_req(struct drbd_work *w, int cancel)
1488{
1489 struct drbd_request *req = container_of(w, struct drbd_request, w);
1490 struct drbd_device *device = req->device;
1491 struct drbd_peer_device *const peer_device = first_peer_device(device);
1492 struct drbd_connection *connection = peer_device->connection;
1493 bool do_send_unplug = req->rq_state & RQ_UNPLUG;
1494 int err;
1495
1496 if (unlikely(cancel)) {
1497 req_mod(req, SEND_CANCELED);
1498 return 0;
1499 }
1500 req->pre_send_jif = jiffies;
1501
1502 /* Even read requests may close a write epoch,
1503 * if there was any yet. */
1504 maybe_send_barrier(connection, req->epoch);
1505
1506 err = drbd_send_drequest(peer_device, P_DATA_REQUEST, req->i.sector, req->i.size,
1507 (unsigned long)req);
1508
1509 req_mod(req, err ? SEND_FAILED : HANDED_OVER_TO_NETWORK);
1510
1511 if (do_send_unplug && !err)
1512 pd_send_unplug_remote(peer_device);
1513
1514 return err;
1515}
1516
1517int w_restart_disk_io(struct drbd_work *w, int cancel)
1518{
1519 struct drbd_request *req = container_of(w, struct drbd_request, w);
1520 struct drbd_device *device = req->device;
1521
1522 if (bio_data_dir(req->master_bio) == WRITE && req->rq_state & RQ_IN_ACT_LOG)
1523 drbd_al_begin_io(device, &req->i);
1524
1525 drbd_req_make_private_bio(req, req->master_bio);
1526 bio_set_dev(req->private_bio, device->ldev->backing_bdev);
1527 generic_make_request(req->private_bio);
1528
1529 return 0;
1530}
1531
1532static int _drbd_may_sync_now(struct drbd_device *device)
1533{
1534 struct drbd_device *odev = device;
1535 int resync_after;
1536
1537 while (1) {
1538 if (!odev->ldev || odev->state.disk == D_DISKLESS)
1539 return 1;
1540 rcu_read_lock();
1541 resync_after = rcu_dereference(odev->ldev->disk_conf)->resync_after;
1542 rcu_read_unlock();
1543 if (resync_after == -1)
1544 return 1;
1545 odev = minor_to_device(resync_after);
1546 if (!odev)
1547 return 1;
1548 if ((odev->state.conn >= C_SYNC_SOURCE &&
1549 odev->state.conn <= C_PAUSED_SYNC_T) ||
1550 odev->state.aftr_isp || odev->state.peer_isp ||
1551 odev->state.user_isp)
1552 return 0;
1553 }
1554}
1555
1556/**
1557 * drbd_pause_after() - Pause resync on all devices that may not resync now
1558 * @device: DRBD device.
1559 *
1560 * Called from process context only (admin command and after_state_ch).
1561 */
1562static bool drbd_pause_after(struct drbd_device *device)
1563{
1564 bool changed = false;
1565 struct drbd_device *odev;
1566 int i;
1567
1568 rcu_read_lock();
1569 idr_for_each_entry(&drbd_devices, odev, i) {
1570 if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS)
1571 continue;
1572 if (!_drbd_may_sync_now(odev) &&
1573 _drbd_set_state(_NS(odev, aftr_isp, 1),
1574 CS_HARD, NULL) != SS_NOTHING_TO_DO)
1575 changed = true;
1576 }
1577 rcu_read_unlock();
1578
1579 return changed;
1580}
1581
1582/**
1583 * drbd_resume_next() - Resume resync on all devices that may resync now
1584 * @device: DRBD device.
1585 *
1586 * Called from process context only (admin command and worker).
1587 */
1588static bool drbd_resume_next(struct drbd_device *device)
1589{
1590 bool changed = false;
1591 struct drbd_device *odev;
1592 int i;
1593
1594 rcu_read_lock();
1595 idr_for_each_entry(&drbd_devices, odev, i) {
1596 if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS)
1597 continue;
1598 if (odev->state.aftr_isp) {
1599 if (_drbd_may_sync_now(odev) &&
1600 _drbd_set_state(_NS(odev, aftr_isp, 0),
1601 CS_HARD, NULL) != SS_NOTHING_TO_DO)
1602 changed = true;
1603 }
1604 }
1605 rcu_read_unlock();
1606 return changed;
1607}
1608
1609void resume_next_sg(struct drbd_device *device)
1610{
1611 lock_all_resources();
1612 drbd_resume_next(device);
1613 unlock_all_resources();
1614}
1615
1616void suspend_other_sg(struct drbd_device *device)
1617{
1618 lock_all_resources();
1619 drbd_pause_after(device);
1620 unlock_all_resources();
1621}
1622
1623/* caller must lock_all_resources() */
1624enum drbd_ret_code drbd_resync_after_valid(struct drbd_device *device, int o_minor)
1625{
1626 struct drbd_device *odev;
1627 int resync_after;
1628
1629 if (o_minor == -1)
1630 return NO_ERROR;
1631 if (o_minor < -1 || o_minor > MINORMASK)
1632 return ERR_RESYNC_AFTER;
1633
1634 /* check for loops */
1635 odev = minor_to_device(o_minor);
1636 while (1) {
1637 if (odev == device)
1638 return ERR_RESYNC_AFTER_CYCLE;
1639
1640 /* You are free to depend on diskless, non-existing,
1641 * or not yet/no longer existing minors.
1642 * We only reject dependency loops.
1643 * We cannot follow the dependency chain beyond a detached or
1644 * missing minor.
1645 */
1646 if (!odev || !odev->ldev || odev->state.disk == D_DISKLESS)
1647 return NO_ERROR;
1648
1649 rcu_read_lock();
1650 resync_after = rcu_dereference(odev->ldev->disk_conf)->resync_after;
1651 rcu_read_unlock();
1652 /* dependency chain ends here, no cycles. */
1653 if (resync_after == -1)
1654 return NO_ERROR;
1655
1656 /* follow the dependency chain */
1657 odev = minor_to_device(resync_after);
1658 }
1659}
1660
1661/* caller must lock_all_resources() */
1662void drbd_resync_after_changed(struct drbd_device *device)
1663{
1664 int changed;
1665
1666 do {
1667 changed = drbd_pause_after(device);
1668 changed |= drbd_resume_next(device);
1669 } while (changed);
1670}
1671
1672void drbd_rs_controller_reset(struct drbd_device *device)
1673{
1674 struct gendisk *disk = device->ldev->backing_bdev->bd_contains->bd_disk;
1675 struct fifo_buffer *plan;
1676
1677 atomic_set(&device->rs_sect_in, 0);
1678 atomic_set(&device->rs_sect_ev, 0);
1679 device->rs_in_flight = 0;
1680 device->rs_last_events = (int)part_stat_read_accum(&disk->part0, sectors);
1681
1682 /* Updating the RCU protected object in place is necessary since
1683 this function gets called from atomic context.
1684 It is valid since all other updates also lead to an completely
1685 empty fifo */
1686 rcu_read_lock();
1687 plan = rcu_dereference(device->rs_plan_s);
1688 plan->total = 0;
1689 fifo_set(plan, 0);
1690 rcu_read_unlock();
1691}
1692
1693void start_resync_timer_fn(struct timer_list *t)
1694{
1695 struct drbd_device *device = from_timer(device, t, start_resync_timer);
1696 drbd_device_post_work(device, RS_START);
1697}
1698
1699static void do_start_resync(struct drbd_device *device)
1700{
1701 if (atomic_read(&device->unacked_cnt) || atomic_read(&device->rs_pending_cnt)) {
1702 drbd_warn(device, "postponing start_resync ...\n");
1703 device->start_resync_timer.expires = jiffies + HZ/10;
1704 add_timer(&device->start_resync_timer);
1705 return;
1706 }
1707
1708 drbd_start_resync(device, C_SYNC_SOURCE);
1709 clear_bit(AHEAD_TO_SYNC_SOURCE, &device->flags);
1710}
1711
1712static bool use_checksum_based_resync(struct drbd_connection *connection, struct drbd_device *device)
1713{
1714 bool csums_after_crash_only;
1715 rcu_read_lock();
1716 csums_after_crash_only = rcu_dereference(connection->net_conf)->csums_after_crash_only;
1717 rcu_read_unlock();
1718 return connection->agreed_pro_version >= 89 && /* supported? */
1719 connection->csums_tfm && /* configured? */
1720 (csums_after_crash_only == false /* use for each resync? */
1721 || test_bit(CRASHED_PRIMARY, &device->flags)); /* or only after Primary crash? */
1722}
1723
1724/**
1725 * drbd_start_resync() - Start the resync process
1726 * @device: DRBD device.
1727 * @side: Either C_SYNC_SOURCE or C_SYNC_TARGET
1728 *
1729 * This function might bring you directly into one of the
1730 * C_PAUSED_SYNC_* states.
1731 */
1732void drbd_start_resync(struct drbd_device *device, enum drbd_conns side)
1733{
1734 struct drbd_peer_device *peer_device = first_peer_device(device);
1735 struct drbd_connection *connection = peer_device ? peer_device->connection : NULL;
1736 union drbd_state ns;
1737 int r;
1738
1739 if (device->state.conn >= C_SYNC_SOURCE && device->state.conn < C_AHEAD) {
1740 drbd_err(device, "Resync already running!\n");
1741 return;
1742 }
1743
1744 if (!connection) {
1745 drbd_err(device, "No connection to peer, aborting!\n");
1746 return;
1747 }
1748
1749 if (!test_bit(B_RS_H_DONE, &device->flags)) {
1750 if (side == C_SYNC_TARGET) {
1751 /* Since application IO was locked out during C_WF_BITMAP_T and
1752 C_WF_SYNC_UUID we are still unmodified. Before going to C_SYNC_TARGET
1753 we check that we might make the data inconsistent. */
1754 r = drbd_khelper(device, "before-resync-target");
1755 r = (r >> 8) & 0xff;
1756 if (r > 0) {
1757 drbd_info(device, "before-resync-target handler returned %d, "
1758 "dropping connection.\n", r);
1759 conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
1760 return;
1761 }
1762 } else /* C_SYNC_SOURCE */ {
1763 r = drbd_khelper(device, "before-resync-source");
1764 r = (r >> 8) & 0xff;
1765 if (r > 0) {
1766 if (r == 3) {
1767 drbd_info(device, "before-resync-source handler returned %d, "
1768 "ignoring. Old userland tools?", r);
1769 } else {
1770 drbd_info(device, "before-resync-source handler returned %d, "
1771 "dropping connection.\n", r);
1772 conn_request_state(connection,
1773 NS(conn, C_DISCONNECTING), CS_HARD);
1774 return;
1775 }
1776 }
1777 }
1778 }
1779
1780 if (current == connection->worker.task) {
1781 /* The worker should not sleep waiting for state_mutex,
1782 that can take long */
1783 if (!mutex_trylock(device->state_mutex)) {
1784 set_bit(B_RS_H_DONE, &device->flags);
1785 device->start_resync_timer.expires = jiffies + HZ/5;
1786 add_timer(&device->start_resync_timer);
1787 return;
1788 }
1789 } else {
1790 mutex_lock(device->state_mutex);
1791 }
1792
1793 lock_all_resources();
1794 clear_bit(B_RS_H_DONE, &device->flags);
1795 /* Did some connection breakage or IO error race with us? */
1796 if (device->state.conn < C_CONNECTED
1797 || !get_ldev_if_state(device, D_NEGOTIATING)) {
1798 unlock_all_resources();
1799 goto out;
1800 }
1801
1802 ns = drbd_read_state(device);
1803
1804 ns.aftr_isp = !_drbd_may_sync_now(device);
1805
1806 ns.conn = side;
1807
1808 if (side == C_SYNC_TARGET)
1809 ns.disk = D_INCONSISTENT;
1810 else /* side == C_SYNC_SOURCE */
1811 ns.pdsk = D_INCONSISTENT;
1812
1813 r = _drbd_set_state(device, ns, CS_VERBOSE, NULL);
1814 ns = drbd_read_state(device);
1815
1816 if (ns.conn < C_CONNECTED)
1817 r = SS_UNKNOWN_ERROR;
1818
1819 if (r == SS_SUCCESS) {
1820 unsigned long tw = drbd_bm_total_weight(device);
1821 unsigned long now = jiffies;
1822 int i;
1823
1824 device->rs_failed = 0;
1825 device->rs_paused = 0;
1826 device->rs_same_csum = 0;
1827 device->rs_last_sect_ev = 0;
1828 device->rs_total = tw;
1829 device->rs_start = now;
1830 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
1831 device->rs_mark_left[i] = tw;
1832 device->rs_mark_time[i] = now;
1833 }
1834 drbd_pause_after(device);
1835 /* Forget potentially stale cached per resync extent bit-counts.
1836 * Open coded drbd_rs_cancel_all(device), we already have IRQs
1837 * disabled, and know the disk state is ok. */
1838 spin_lock(&device->al_lock);
1839 lc_reset(device->resync);
1840 device->resync_locked = 0;
1841 device->resync_wenr = LC_FREE;
1842 spin_unlock(&device->al_lock);
1843 }
1844 unlock_all_resources();
1845
1846 if (r == SS_SUCCESS) {
1847 wake_up(&device->al_wait); /* for lc_reset() above */
1848 /* reset rs_last_bcast when a resync or verify is started,
1849 * to deal with potential jiffies wrap. */
1850 device->rs_last_bcast = jiffies - HZ;
1851
1852 drbd_info(device, "Began resync as %s (will sync %lu KB [%lu bits set]).\n",
1853 drbd_conn_str(ns.conn),
1854 (unsigned long) device->rs_total << (BM_BLOCK_SHIFT-10),
1855 (unsigned long) device->rs_total);
1856 if (side == C_SYNC_TARGET) {
1857 device->bm_resync_fo = 0;
1858 device->use_csums = use_checksum_based_resync(connection, device);
1859 } else {
1860 device->use_csums = false;
1861 }
1862
1863 /* Since protocol 96, we must serialize drbd_gen_and_send_sync_uuid
1864 * with w_send_oos, or the sync target will get confused as to
1865 * how much bits to resync. We cannot do that always, because for an
1866 * empty resync and protocol < 95, we need to do it here, as we call
1867 * drbd_resync_finished from here in that case.
1868 * We drbd_gen_and_send_sync_uuid here for protocol < 96,
1869 * and from after_state_ch otherwise. */
1870 if (side == C_SYNC_SOURCE && connection->agreed_pro_version < 96)
1871 drbd_gen_and_send_sync_uuid(peer_device);
1872
1873 if (connection->agreed_pro_version < 95 && device->rs_total == 0) {
1874 /* This still has a race (about when exactly the peers
1875 * detect connection loss) that can lead to a full sync
1876 * on next handshake. In 8.3.9 we fixed this with explicit
1877 * resync-finished notifications, but the fix
1878 * introduces a protocol change. Sleeping for some
1879 * time longer than the ping interval + timeout on the
1880 * SyncSource, to give the SyncTarget the chance to
1881 * detect connection loss, then waiting for a ping
1882 * response (implicit in drbd_resync_finished) reduces
1883 * the race considerably, but does not solve it. */
1884 if (side == C_SYNC_SOURCE) {
1885 struct net_conf *nc;
1886 int timeo;
1887
1888 rcu_read_lock();
1889 nc = rcu_dereference(connection->net_conf);
1890 timeo = nc->ping_int * HZ + nc->ping_timeo * HZ / 9;
1891 rcu_read_unlock();
1892 schedule_timeout_interruptible(timeo);
1893 }
1894 drbd_resync_finished(device);
1895 }
1896
1897 drbd_rs_controller_reset(device);
1898 /* ns.conn may already be != device->state.conn,
1899 * we may have been paused in between, or become paused until
1900 * the timer triggers.
1901 * No matter, that is handled in resync_timer_fn() */
1902 if (ns.conn == C_SYNC_TARGET)
1903 mod_timer(&device->resync_timer, jiffies);
1904
1905 drbd_md_sync(device);
1906 }
1907 put_ldev(device);
1908out:
1909 mutex_unlock(device->state_mutex);
1910}
1911
1912static void update_on_disk_bitmap(struct drbd_device *device, bool resync_done)
1913{
1914 struct sib_info sib = { .sib_reason = SIB_SYNC_PROGRESS, };
1915 device->rs_last_bcast = jiffies;
1916
1917 if (!get_ldev(device))
1918 return;
1919
1920 drbd_bm_write_lazy(device, 0);
1921 if (resync_done && is_sync_state(device->state.conn))
1922 drbd_resync_finished(device);
1923
1924 drbd_bcast_event(device, &sib);
1925 /* update timestamp, in case it took a while to write out stuff */
1926 device->rs_last_bcast = jiffies;
1927 put_ldev(device);
1928}
1929
1930static void drbd_ldev_destroy(struct drbd_device *device)
1931{
1932 lc_destroy(device->resync);
1933 device->resync = NULL;
1934 lc_destroy(device->act_log);
1935 device->act_log = NULL;
1936
1937 __acquire(local);
1938 drbd_backing_dev_free(device, device->ldev);
1939 device->ldev = NULL;
1940 __release(local);
1941
1942 clear_bit(GOING_DISKLESS, &device->flags);
1943 wake_up(&device->misc_wait);
1944}
1945
1946static void go_diskless(struct drbd_device *device)
1947{
1948 D_ASSERT(device, device->state.disk == D_FAILED);
1949 /* we cannot assert local_cnt == 0 here, as get_ldev_if_state will
1950 * inc/dec it frequently. Once we are D_DISKLESS, no one will touch
1951 * the protected members anymore, though, so once put_ldev reaches zero
1952 * again, it will be safe to free them. */
1953
1954 /* Try to write changed bitmap pages, read errors may have just
1955 * set some bits outside the area covered by the activity log.
1956 *
1957 * If we have an IO error during the bitmap writeout,
1958 * we will want a full sync next time, just in case.
1959 * (Do we want a specific meta data flag for this?)
1960 *
1961 * If that does not make it to stable storage either,
1962 * we cannot do anything about that anymore.
1963 *
1964 * We still need to check if both bitmap and ldev are present, we may
1965 * end up here after a failed attach, before ldev was even assigned.
1966 */
1967 if (device->bitmap && device->ldev) {
1968 /* An interrupted resync or similar is allowed to recounts bits
1969 * while we detach.
1970 * Any modifications would not be expected anymore, though.
1971 */
1972 if (drbd_bitmap_io_from_worker(device, drbd_bm_write,
1973 "detach", BM_LOCKED_TEST_ALLOWED)) {
1974 if (test_bit(WAS_READ_ERROR, &device->flags)) {
1975 drbd_md_set_flag(device, MDF_FULL_SYNC);
1976 drbd_md_sync(device);
1977 }
1978 }
1979 }
1980
1981 drbd_force_state(device, NS(disk, D_DISKLESS));
1982}
1983
1984static int do_md_sync(struct drbd_device *device)
1985{
1986 drbd_warn(device, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
1987 drbd_md_sync(device);
1988 return 0;
1989}
1990
1991/* only called from drbd_worker thread, no locking */
1992void __update_timing_details(
1993 struct drbd_thread_timing_details *tdp,
1994 unsigned int *cb_nr,
1995 void *cb,
1996 const char *fn, const unsigned int line)
1997{
1998 unsigned int i = *cb_nr % DRBD_THREAD_DETAILS_HIST;
1999 struct drbd_thread_timing_details *td = tdp + i;
2000
2001 td->start_jif = jiffies;
2002 td->cb_addr = cb;
2003 td->caller_fn = fn;
2004 td->line = line;
2005 td->cb_nr = *cb_nr;
2006
2007 i = (i+1) % DRBD_THREAD_DETAILS_HIST;
2008 td = tdp + i;
2009 memset(td, 0, sizeof(*td));
2010
2011 ++(*cb_nr);
2012}
2013
2014static void do_device_work(struct drbd_device *device, const unsigned long todo)
2015{
2016 if (test_bit(MD_SYNC, &todo))
2017 do_md_sync(device);
2018 if (test_bit(RS_DONE, &todo) ||
2019 test_bit(RS_PROGRESS, &todo))
2020 update_on_disk_bitmap(device, test_bit(RS_DONE, &todo));
2021 if (test_bit(GO_DISKLESS, &todo))
2022 go_diskless(device);
2023 if (test_bit(DESTROY_DISK, &todo))
2024 drbd_ldev_destroy(device);
2025 if (test_bit(RS_START, &todo))
2026 do_start_resync(device);
2027}
2028
2029#define DRBD_DEVICE_WORK_MASK \
2030 ((1UL << GO_DISKLESS) \
2031 |(1UL << DESTROY_DISK) \
2032 |(1UL << MD_SYNC) \
2033 |(1UL << RS_START) \
2034 |(1UL << RS_PROGRESS) \
2035 |(1UL << RS_DONE) \
2036 )
2037
2038static unsigned long get_work_bits(unsigned long *flags)
2039{
2040 unsigned long old, new;
2041 do {
2042 old = *flags;
2043 new = old & ~DRBD_DEVICE_WORK_MASK;
2044 } while (cmpxchg(flags, old, new) != old);
2045 return old & DRBD_DEVICE_WORK_MASK;
2046}
2047
2048static void do_unqueued_work(struct drbd_connection *connection)
2049{
2050 struct drbd_peer_device *peer_device;
2051 int vnr;
2052
2053 rcu_read_lock();
2054 idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
2055 struct drbd_device *device = peer_device->device;
2056 unsigned long todo = get_work_bits(&device->flags);
2057 if (!todo)
2058 continue;
2059
2060 kref_get(&device->kref);
2061 rcu_read_unlock();
2062 do_device_work(device, todo);
2063 kref_put(&device->kref, drbd_destroy_device);
2064 rcu_read_lock();
2065 }
2066 rcu_read_unlock();
2067}
2068
2069static bool dequeue_work_batch(struct drbd_work_queue *queue, struct list_head *work_list)
2070{
2071 spin_lock_irq(&queue->q_lock);
2072 list_splice_tail_init(&queue->q, work_list);
2073 spin_unlock_irq(&queue->q_lock);
2074 return !list_empty(work_list);
2075}
2076
2077static void wait_for_work(struct drbd_connection *connection, struct list_head *work_list)
2078{
2079 DEFINE_WAIT(wait);
2080 struct net_conf *nc;
2081 int uncork, cork;
2082
2083 dequeue_work_batch(&connection->sender_work, work_list);
2084 if (!list_empty(work_list))
2085 return;
2086
2087 /* Still nothing to do?
2088 * Maybe we still need to close the current epoch,
2089 * even if no new requests are queued yet.
2090 *
2091 * Also, poke TCP, just in case.
2092 * Then wait for new work (or signal). */
2093 rcu_read_lock();
2094 nc = rcu_dereference(connection->net_conf);
2095 uncork = nc ? nc->tcp_cork : 0;
2096 rcu_read_unlock();
2097 if (uncork) {
2098 mutex_lock(&connection->data.mutex);
2099 if (connection->data.socket)
2100 drbd_tcp_uncork(connection->data.socket);
2101 mutex_unlock(&connection->data.mutex);
2102 }
2103
2104 for (;;) {
2105 int send_barrier;
2106 prepare_to_wait(&connection->sender_work.q_wait, &wait, TASK_INTERRUPTIBLE);
2107 spin_lock_irq(&connection->resource->req_lock);
2108 spin_lock(&connection->sender_work.q_lock); /* FIXME get rid of this one? */
2109 if (!list_empty(&connection->sender_work.q))
2110 list_splice_tail_init(&connection->sender_work.q, work_list);
2111 spin_unlock(&connection->sender_work.q_lock); /* FIXME get rid of this one? */
2112 if (!list_empty(work_list) || signal_pending(current)) {
2113 spin_unlock_irq(&connection->resource->req_lock);
2114 break;
2115 }
2116
2117 /* We found nothing new to do, no to-be-communicated request,
2118 * no other work item. We may still need to close the last
2119 * epoch. Next incoming request epoch will be connection ->
2120 * current transfer log epoch number. If that is different
2121 * from the epoch of the last request we communicated, it is
2122 * safe to send the epoch separating barrier now.
2123 */
2124 send_barrier =
2125 atomic_read(&connection->current_tle_nr) !=
2126 connection->send.current_epoch_nr;
2127 spin_unlock_irq(&connection->resource->req_lock);
2128
2129 if (send_barrier)
2130 maybe_send_barrier(connection,
2131 connection->send.current_epoch_nr + 1);
2132
2133 if (test_bit(DEVICE_WORK_PENDING, &connection->flags))
2134 break;
2135
2136 /* drbd_send() may have called flush_signals() */
2137 if (get_t_state(&connection->worker) != RUNNING)
2138 break;
2139
2140 schedule();
2141 /* may be woken up for other things but new work, too,
2142 * e.g. if the current epoch got closed.
2143 * In which case we send the barrier above. */
2144 }
2145 finish_wait(&connection->sender_work.q_wait, &wait);
2146
2147 /* someone may have changed the config while we have been waiting above. */
2148 rcu_read_lock();
2149 nc = rcu_dereference(connection->net_conf);
2150 cork = nc ? nc->tcp_cork : 0;
2151 rcu_read_unlock();
2152 mutex_lock(&connection->data.mutex);
2153 if (connection->data.socket) {
2154 if (cork)
2155 drbd_tcp_cork(connection->data.socket);
2156 else if (!uncork)
2157 drbd_tcp_uncork(connection->data.socket);
2158 }
2159 mutex_unlock(&connection->data.mutex);
2160}
2161
2162int drbd_worker(struct drbd_thread *thi)
2163{
2164 struct drbd_connection *connection = thi->connection;
2165 struct drbd_work *w = NULL;
2166 struct drbd_peer_device *peer_device;
2167 LIST_HEAD(work_list);
2168 int vnr;
2169
2170 while (get_t_state(thi) == RUNNING) {
2171 drbd_thread_current_set_cpu(thi);
2172
2173 if (list_empty(&work_list)) {
2174 update_worker_timing_details(connection, wait_for_work);
2175 wait_for_work(connection, &work_list);
2176 }
2177
2178 if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) {
2179 update_worker_timing_details(connection, do_unqueued_work);
2180 do_unqueued_work(connection);
2181 }
2182
2183 if (signal_pending(current)) {
2184 flush_signals(current);
2185 if (get_t_state(thi) == RUNNING) {
2186 drbd_warn(connection, "Worker got an unexpected signal\n");
2187 continue;
2188 }
2189 break;
2190 }
2191
2192 if (get_t_state(thi) != RUNNING)
2193 break;
2194
2195 if (!list_empty(&work_list)) {
2196 w = list_first_entry(&work_list, struct drbd_work, list);
2197 list_del_init(&w->list);
2198 update_worker_timing_details(connection, w->cb);
2199 if (w->cb(w, connection->cstate < C_WF_REPORT_PARAMS) == 0)
2200 continue;
2201 if (connection->cstate >= C_WF_REPORT_PARAMS)
2202 conn_request_state(connection, NS(conn, C_NETWORK_FAILURE), CS_HARD);
2203 }
2204 }
2205
2206 do {
2207 if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) {
2208 update_worker_timing_details(connection, do_unqueued_work);
2209 do_unqueued_work(connection);
2210 }
2211 if (!list_empty(&work_list)) {
2212 w = list_first_entry(&work_list, struct drbd_work, list);
2213 list_del_init(&w->list);
2214 update_worker_timing_details(connection, w->cb);
2215 w->cb(w, 1);
2216 } else
2217 dequeue_work_batch(&connection->sender_work, &work_list);
2218 } while (!list_empty(&work_list) || test_bit(DEVICE_WORK_PENDING, &connection->flags));
2219
2220 rcu_read_lock();
2221 idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
2222 struct drbd_device *device = peer_device->device;
2223 D_ASSERT(device, device->state.disk == D_DISKLESS && device->state.conn == C_STANDALONE);
2224 kref_get(&device->kref);
2225 rcu_read_unlock();
2226 drbd_device_cleanup(device);
2227 kref_put(&device->kref, drbd_destroy_device);
2228 rcu_read_lock();
2229 }
2230 rcu_read_unlock();
2231
2232 return 0;
2233}