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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-only
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#include <linux/part_stat.h>
26
27#include "drbd_int.h"
28#include "drbd_protocol.h"
29#include "drbd_req.h"
30
31static int make_ov_request(struct drbd_peer_device *, int);
32static int make_resync_request(struct drbd_peer_device *, int);
33
34/* endio handlers:
35 * drbd_md_endio (defined here)
36 * drbd_request_endio (defined here)
37 * drbd_peer_request_endio (defined here)
38 * drbd_bm_endio (defined in drbd_bitmap.c)
39 *
40 * For all these callbacks, note the following:
41 * The callbacks will be called in irq context by the IDE drivers,
42 * and in Softirqs/Tasklets/BH context by the SCSI drivers.
43 * Try to get the locking right :)
44 *
45 */
46
47/* used for synchronous meta data and bitmap IO
48 * submitted by drbd_md_sync_page_io()
49 */
50void drbd_md_endio(struct bio *bio)
51{
52 struct drbd_device *device;
53
54 device = bio->bi_private;
55 device->md_io.error = blk_status_to_errno(bio->bi_status);
56
57 /* special case: drbd_md_read() during drbd_adm_attach() */
58 if (device->ldev)
59 put_ldev(device);
60 bio_put(bio);
61
62 /* We grabbed an extra reference in _drbd_md_sync_page_io() to be able
63 * to timeout on the lower level device, and eventually detach from it.
64 * If this io completion runs after that timeout expired, this
65 * drbd_md_put_buffer() may allow us to finally try and re-attach.
66 * During normal operation, this only puts that extra reference
67 * down to 1 again.
68 * Make sure we first drop the reference, and only then signal
69 * completion, or we may (in drbd_al_read_log()) cycle so fast into the
70 * next drbd_md_sync_page_io(), that we trigger the
71 * ASSERT(atomic_read(&device->md_io_in_use) == 1) there.
72 */
73 drbd_md_put_buffer(device);
74 device->md_io.done = 1;
75 wake_up(&device->misc_wait);
76}
77
78/* reads on behalf of the partner,
79 * "submitted" by the receiver
80 */
81static void drbd_endio_read_sec_final(struct drbd_peer_request *peer_req) __releases(local)
82{
83 unsigned long flags = 0;
84 struct drbd_peer_device *peer_device = peer_req->peer_device;
85 struct drbd_device *device = peer_device->device;
86
87 spin_lock_irqsave(&device->resource->req_lock, flags);
88 device->read_cnt += peer_req->i.size >> 9;
89 list_del(&peer_req->w.list);
90 if (list_empty(&device->read_ee))
91 wake_up(&device->ee_wait);
92 if (test_bit(__EE_WAS_ERROR, &peer_req->flags))
93 __drbd_chk_io_error(device, DRBD_READ_ERROR);
94 spin_unlock_irqrestore(&device->resource->req_lock, flags);
95
96 drbd_queue_work(&peer_device->connection->sender_work, &peer_req->w);
97 put_ldev(device);
98}
99
100/* writes on behalf of the partner, or resync writes,
101 * "submitted" by the receiver, final stage. */
102void drbd_endio_write_sec_final(struct drbd_peer_request *peer_req) __releases(local)
103{
104 unsigned long flags = 0;
105 struct drbd_peer_device *peer_device = peer_req->peer_device;
106 struct drbd_device *device = peer_device->device;
107 struct drbd_connection *connection = peer_device->connection;
108 struct drbd_interval i;
109 int do_wake;
110 u64 block_id;
111 int do_al_complete_io;
112
113 /* after we moved peer_req to done_ee,
114 * we may no longer access it,
115 * it may be freed/reused already!
116 * (as soon as we release the req_lock) */
117 i = peer_req->i;
118 do_al_complete_io = peer_req->flags & EE_CALL_AL_COMPLETE_IO;
119 block_id = peer_req->block_id;
120 peer_req->flags &= ~EE_CALL_AL_COMPLETE_IO;
121
122 if (peer_req->flags & EE_WAS_ERROR) {
123 /* In protocol != C, we usually do not send write acks.
124 * In case of a write error, send the neg ack anyways. */
125 if (!__test_and_set_bit(__EE_SEND_WRITE_ACK, &peer_req->flags))
126 inc_unacked(device);
127 drbd_set_out_of_sync(peer_device, peer_req->i.sector, peer_req->i.size);
128 }
129
130 spin_lock_irqsave(&device->resource->req_lock, flags);
131 device->writ_cnt += peer_req->i.size >> 9;
132 list_move_tail(&peer_req->w.list, &device->done_ee);
133
134 /*
135 * Do not remove from the write_requests tree here: we did not send the
136 * Ack yet and did not wake possibly waiting conflicting requests.
137 * Removed from the tree from "drbd_process_done_ee" within the
138 * appropriate dw.cb (e_end_block/e_end_resync_block) or from
139 * _drbd_clear_done_ee.
140 */
141
142 do_wake = list_empty(block_id == ID_SYNCER ? &device->sync_ee : &device->active_ee);
143
144 /* FIXME do we want to detach for failed REQ_OP_DISCARD?
145 * ((peer_req->flags & (EE_WAS_ERROR|EE_TRIM)) == EE_WAS_ERROR) */
146 if (peer_req->flags & EE_WAS_ERROR)
147 __drbd_chk_io_error(device, DRBD_WRITE_ERROR);
148
149 if (connection->cstate >= C_WF_REPORT_PARAMS) {
150 kref_get(&device->kref); /* put is in drbd_send_acks_wf() */
151 if (!queue_work(connection->ack_sender, &peer_device->send_acks_work))
152 kref_put(&device->kref, drbd_destroy_device);
153 }
154 spin_unlock_irqrestore(&device->resource->req_lock, flags);
155
156 if (block_id == ID_SYNCER)
157 drbd_rs_complete_io(device, i.sector);
158
159 if (do_wake)
160 wake_up(&device->ee_wait);
161
162 if (do_al_complete_io)
163 drbd_al_complete_io(device, &i);
164
165 put_ldev(device);
166}
167
168/* writes on behalf of the partner, or resync writes,
169 * "submitted" by the receiver.
170 */
171void drbd_peer_request_endio(struct bio *bio)
172{
173 struct drbd_peer_request *peer_req = bio->bi_private;
174 struct drbd_device *device = peer_req->peer_device->device;
175 bool is_write = bio_data_dir(bio) == WRITE;
176 bool is_discard = bio_op(bio) == REQ_OP_WRITE_ZEROES ||
177 bio_op(bio) == REQ_OP_DISCARD;
178
179 if (bio->bi_status && drbd_ratelimit())
180 drbd_warn(device, "%s: error=%d s=%llus\n",
181 is_write ? (is_discard ? "discard" : "write")
182 : "read", bio->bi_status,
183 (unsigned long long)peer_req->i.sector);
184
185 if (bio->bi_status)
186 set_bit(__EE_WAS_ERROR, &peer_req->flags);
187
188 bio_put(bio); /* no need for the bio anymore */
189 if (atomic_dec_and_test(&peer_req->pending_bios)) {
190 if (is_write)
191 drbd_endio_write_sec_final(peer_req);
192 else
193 drbd_endio_read_sec_final(peer_req);
194 }
195}
196
197static void
198drbd_panic_after_delayed_completion_of_aborted_request(struct drbd_device *device)
199{
200 panic("drbd%u %s/%u potential random memory corruption caused by delayed completion of aborted local request\n",
201 device->minor, device->resource->name, device->vnr);
202}
203
204/* read, readA or write requests on R_PRIMARY coming from drbd_make_request
205 */
206void drbd_request_endio(struct bio *bio)
207{
208 unsigned long flags;
209 struct drbd_request *req = bio->bi_private;
210 struct drbd_device *device = req->device;
211 struct bio_and_error m;
212 enum drbd_req_event what;
213
214 /* If this request was aborted locally before,
215 * but now was completed "successfully",
216 * chances are that this caused arbitrary data corruption.
217 *
218 * "aborting" requests, or force-detaching the disk, is intended for
219 * completely blocked/hung local backing devices which do no longer
220 * complete requests at all, not even do error completions. In this
221 * situation, usually a hard-reset and failover is the only way out.
222 *
223 * By "aborting", basically faking a local error-completion,
224 * we allow for a more graceful swichover by cleanly migrating services.
225 * Still the affected node has to be rebooted "soon".
226 *
227 * By completing these requests, we allow the upper layers to re-use
228 * the associated data pages.
229 *
230 * If later the local backing device "recovers", and now DMAs some data
231 * from disk into the original request pages, in the best case it will
232 * just put random data into unused pages; but typically it will corrupt
233 * meanwhile completely unrelated data, causing all sorts of damage.
234 *
235 * Which means delayed successful completion,
236 * especially for READ requests,
237 * is a reason to panic().
238 *
239 * We assume that a delayed *error* completion is OK,
240 * though we still will complain noisily about it.
241 */
242 if (unlikely(req->rq_state & RQ_LOCAL_ABORTED)) {
243 if (drbd_ratelimit())
244 drbd_emerg(device, "delayed completion of aborted local request; disk-timeout may be too aggressive\n");
245
246 if (!bio->bi_status)
247 drbd_panic_after_delayed_completion_of_aborted_request(device);
248 }
249
250 /* to avoid recursion in __req_mod */
251 if (unlikely(bio->bi_status)) {
252 switch (bio_op(bio)) {
253 case REQ_OP_WRITE_ZEROES:
254 case REQ_OP_DISCARD:
255 if (bio->bi_status == BLK_STS_NOTSUPP)
256 what = DISCARD_COMPLETED_NOTSUPP;
257 else
258 what = DISCARD_COMPLETED_WITH_ERROR;
259 break;
260 case REQ_OP_READ:
261 if (bio->bi_opf & REQ_RAHEAD)
262 what = READ_AHEAD_COMPLETED_WITH_ERROR;
263 else
264 what = READ_COMPLETED_WITH_ERROR;
265 break;
266 default:
267 what = WRITE_COMPLETED_WITH_ERROR;
268 break;
269 }
270 } else {
271 what = COMPLETED_OK;
272 }
273
274 req->private_bio = ERR_PTR(blk_status_to_errno(bio->bi_status));
275 bio_put(bio);
276
277 /* not req_mod(), we need irqsave here! */
278 spin_lock_irqsave(&device->resource->req_lock, flags);
279 __req_mod(req, what, NULL, &m);
280 spin_unlock_irqrestore(&device->resource->req_lock, flags);
281 put_ldev(device);
282
283 if (m.bio)
284 complete_master_bio(device, &m);
285}
286
287void drbd_csum_ee(struct crypto_shash *tfm, struct drbd_peer_request *peer_req, void *digest)
288{
289 SHASH_DESC_ON_STACK(desc, tfm);
290 struct page *page = peer_req->pages;
291 struct page *tmp;
292 unsigned len;
293 void *src;
294
295 desc->tfm = tfm;
296
297 crypto_shash_init(desc);
298
299 src = kmap_atomic(page);
300 while ((tmp = page_chain_next(page))) {
301 /* all but the last page will be fully used */
302 crypto_shash_update(desc, src, PAGE_SIZE);
303 kunmap_atomic(src);
304 page = tmp;
305 src = kmap_atomic(page);
306 }
307 /* and now the last, possibly only partially used page */
308 len = peer_req->i.size & (PAGE_SIZE - 1);
309 crypto_shash_update(desc, src, len ?: PAGE_SIZE);
310 kunmap_atomic(src);
311
312 crypto_shash_final(desc, digest);
313 shash_desc_zero(desc);
314}
315
316void drbd_csum_bio(struct crypto_shash *tfm, struct bio *bio, void *digest)
317{
318 SHASH_DESC_ON_STACK(desc, tfm);
319 struct bio_vec bvec;
320 struct bvec_iter iter;
321
322 desc->tfm = tfm;
323
324 crypto_shash_init(desc);
325
326 bio_for_each_segment(bvec, bio, iter) {
327 u8 *src;
328
329 src = bvec_kmap_local(&bvec);
330 crypto_shash_update(desc, src, bvec.bv_len);
331 kunmap_local(src);
332 }
333 crypto_shash_final(desc, digest);
334 shash_desc_zero(desc);
335}
336
337/* MAYBE merge common code with w_e_end_ov_req */
338static int w_e_send_csum(struct drbd_work *w, int cancel)
339{
340 struct drbd_peer_request *peer_req = container_of(w, struct drbd_peer_request, w);
341 struct drbd_peer_device *peer_device = peer_req->peer_device;
342 struct drbd_device *device = peer_device->device;
343 int digest_size;
344 void *digest;
345 int err = 0;
346
347 if (unlikely(cancel))
348 goto out;
349
350 if (unlikely((peer_req->flags & EE_WAS_ERROR) != 0))
351 goto out;
352
353 digest_size = crypto_shash_digestsize(peer_device->connection->csums_tfm);
354 digest = kmalloc(digest_size, GFP_NOIO);
355 if (digest) {
356 sector_t sector = peer_req->i.sector;
357 unsigned int size = peer_req->i.size;
358 drbd_csum_ee(peer_device->connection->csums_tfm, peer_req, digest);
359 /* Free peer_req and pages before send.
360 * In case we block on congestion, we could otherwise run into
361 * some distributed deadlock, if the other side blocks on
362 * congestion as well, because our receiver blocks in
363 * drbd_alloc_pages due to pp_in_use > max_buffers. */
364 drbd_free_peer_req(device, peer_req);
365 peer_req = NULL;
366 inc_rs_pending(peer_device);
367 err = drbd_send_drequest_csum(peer_device, sector, size,
368 digest, digest_size,
369 P_CSUM_RS_REQUEST);
370 kfree(digest);
371 } else {
372 drbd_err(device, "kmalloc() of digest failed.\n");
373 err = -ENOMEM;
374 }
375
376out:
377 if (peer_req)
378 drbd_free_peer_req(device, peer_req);
379
380 if (unlikely(err))
381 drbd_err(device, "drbd_send_drequest(..., csum) failed\n");
382 return err;
383}
384
385#define GFP_TRY (__GFP_HIGHMEM | __GFP_NOWARN)
386
387static int read_for_csum(struct drbd_peer_device *peer_device, sector_t sector, int size)
388{
389 struct drbd_device *device = peer_device->device;
390 struct drbd_peer_request *peer_req;
391
392 if (!get_ldev(device))
393 return -EIO;
394
395 /* GFP_TRY, because if there is no memory available right now, this may
396 * be rescheduled for later. It is "only" background resync, after all. */
397 peer_req = drbd_alloc_peer_req(peer_device, ID_SYNCER /* unused */, sector,
398 size, size, GFP_TRY);
399 if (!peer_req)
400 goto defer;
401
402 peer_req->w.cb = w_e_send_csum;
403 peer_req->opf = REQ_OP_READ;
404 spin_lock_irq(&device->resource->req_lock);
405 list_add_tail(&peer_req->w.list, &device->read_ee);
406 spin_unlock_irq(&device->resource->req_lock);
407
408 atomic_add(size >> 9, &device->rs_sect_ev);
409 if (drbd_submit_peer_request(peer_req) == 0)
410 return 0;
411
412 /* If it failed because of ENOMEM, retry should help. If it failed
413 * because bio_add_page failed (probably broken lower level driver),
414 * retry may or may not help.
415 * If it does not, you may need to force disconnect. */
416 spin_lock_irq(&device->resource->req_lock);
417 list_del(&peer_req->w.list);
418 spin_unlock_irq(&device->resource->req_lock);
419
420 drbd_free_peer_req(device, peer_req);
421defer:
422 put_ldev(device);
423 return -EAGAIN;
424}
425
426int w_resync_timer(struct drbd_work *w, int cancel)
427{
428 struct drbd_device *device =
429 container_of(w, struct drbd_device, resync_work);
430
431 switch (device->state.conn) {
432 case C_VERIFY_S:
433 make_ov_request(first_peer_device(device), cancel);
434 break;
435 case C_SYNC_TARGET:
436 make_resync_request(first_peer_device(device), cancel);
437 break;
438 }
439
440 return 0;
441}
442
443void resync_timer_fn(struct timer_list *t)
444{
445 struct drbd_device *device = from_timer(device, t, resync_timer);
446
447 drbd_queue_work_if_unqueued(
448 &first_peer_device(device)->connection->sender_work,
449 &device->resync_work);
450}
451
452static void fifo_set(struct fifo_buffer *fb, int value)
453{
454 int i;
455
456 for (i = 0; i < fb->size; i++)
457 fb->values[i] = value;
458}
459
460static int fifo_push(struct fifo_buffer *fb, int value)
461{
462 int ov;
463
464 ov = fb->values[fb->head_index];
465 fb->values[fb->head_index++] = value;
466
467 if (fb->head_index >= fb->size)
468 fb->head_index = 0;
469
470 return ov;
471}
472
473static void fifo_add_val(struct fifo_buffer *fb, int value)
474{
475 int i;
476
477 for (i = 0; i < fb->size; i++)
478 fb->values[i] += value;
479}
480
481struct fifo_buffer *fifo_alloc(unsigned int fifo_size)
482{
483 struct fifo_buffer *fb;
484
485 fb = kzalloc(struct_size(fb, values, fifo_size), GFP_NOIO);
486 if (!fb)
487 return NULL;
488
489 fb->head_index = 0;
490 fb->size = fifo_size;
491 fb->total = 0;
492
493 return fb;
494}
495
496static int drbd_rs_controller(struct drbd_peer_device *peer_device, unsigned int sect_in)
497{
498 struct drbd_device *device = peer_device->device;
499 struct disk_conf *dc;
500 unsigned int want; /* The number of sectors we want in-flight */
501 int req_sect; /* Number of sectors to request in this turn */
502 int correction; /* Number of sectors more we need in-flight */
503 int cps; /* correction per invocation of drbd_rs_controller() */
504 int steps; /* Number of time steps to plan ahead */
505 int curr_corr;
506 int max_sect;
507 struct fifo_buffer *plan;
508
509 dc = rcu_dereference(device->ldev->disk_conf);
510 plan = rcu_dereference(device->rs_plan_s);
511
512 steps = plan->size; /* (dc->c_plan_ahead * 10 * SLEEP_TIME) / HZ; */
513
514 if (device->rs_in_flight + sect_in == 0) { /* At start of resync */
515 want = ((dc->resync_rate * 2 * SLEEP_TIME) / HZ) * steps;
516 } else { /* normal path */
517 want = dc->c_fill_target ? dc->c_fill_target :
518 sect_in * dc->c_delay_target * HZ / (SLEEP_TIME * 10);
519 }
520
521 correction = want - device->rs_in_flight - plan->total;
522
523 /* Plan ahead */
524 cps = correction / steps;
525 fifo_add_val(plan, cps);
526 plan->total += cps * steps;
527
528 /* What we do in this step */
529 curr_corr = fifo_push(plan, 0);
530 plan->total -= curr_corr;
531
532 req_sect = sect_in + curr_corr;
533 if (req_sect < 0)
534 req_sect = 0;
535
536 max_sect = (dc->c_max_rate * 2 * SLEEP_TIME) / HZ;
537 if (req_sect > max_sect)
538 req_sect = max_sect;
539
540 /*
541 drbd_warn(device, "si=%u if=%d wa=%u co=%d st=%d cps=%d pl=%d cc=%d rs=%d\n",
542 sect_in, device->rs_in_flight, want, correction,
543 steps, cps, device->rs_planed, curr_corr, req_sect);
544 */
545
546 return req_sect;
547}
548
549static int drbd_rs_number_requests(struct drbd_peer_device *peer_device)
550{
551 struct drbd_device *device = peer_device->device;
552 unsigned int sect_in; /* Number of sectors that came in since the last turn */
553 int number, mxb;
554
555 sect_in = atomic_xchg(&device->rs_sect_in, 0);
556 device->rs_in_flight -= sect_in;
557
558 rcu_read_lock();
559 mxb = drbd_get_max_buffers(device) / 2;
560 if (rcu_dereference(device->rs_plan_s)->size) {
561 number = drbd_rs_controller(peer_device, sect_in) >> (BM_BLOCK_SHIFT - 9);
562 device->c_sync_rate = number * HZ * (BM_BLOCK_SIZE / 1024) / SLEEP_TIME;
563 } else {
564 device->c_sync_rate = rcu_dereference(device->ldev->disk_conf)->resync_rate;
565 number = SLEEP_TIME * device->c_sync_rate / ((BM_BLOCK_SIZE / 1024) * HZ);
566 }
567 rcu_read_unlock();
568
569 /* Don't have more than "max-buffers"/2 in-flight.
570 * Otherwise we may cause the remote site to stall on drbd_alloc_pages(),
571 * potentially causing a distributed deadlock on congestion during
572 * online-verify or (checksum-based) resync, if max-buffers,
573 * socket buffer sizes and resync rate settings are mis-configured. */
574
575 /* note that "number" is in units of "BM_BLOCK_SIZE" (which is 4k),
576 * mxb (as used here, and in drbd_alloc_pages on the peer) is
577 * "number of pages" (typically also 4k),
578 * but "rs_in_flight" is in "sectors" (512 Byte). */
579 if (mxb - device->rs_in_flight/8 < number)
580 number = mxb - device->rs_in_flight/8;
581
582 return number;
583}
584
585static int make_resync_request(struct drbd_peer_device *const peer_device, int cancel)
586{
587 struct drbd_device *const device = peer_device->device;
588 struct drbd_connection *const connection = peer_device ? peer_device->connection : NULL;
589 unsigned long bit;
590 sector_t sector;
591 const sector_t capacity = get_capacity(device->vdisk);
592 int max_bio_size;
593 int number, rollback_i, size;
594 int align, requeue = 0;
595 int i = 0;
596 int discard_granularity = 0;
597
598 if (unlikely(cancel))
599 return 0;
600
601 if (device->rs_total == 0) {
602 /* empty resync? */
603 drbd_resync_finished(peer_device);
604 return 0;
605 }
606
607 if (!get_ldev(device)) {
608 /* Since we only need to access device->rsync a
609 get_ldev_if_state(device,D_FAILED) would be sufficient, but
610 to continue resync with a broken disk makes no sense at
611 all */
612 drbd_err(device, "Disk broke down during resync!\n");
613 return 0;
614 }
615
616 if (connection->agreed_features & DRBD_FF_THIN_RESYNC) {
617 rcu_read_lock();
618 discard_granularity = rcu_dereference(device->ldev->disk_conf)->rs_discard_granularity;
619 rcu_read_unlock();
620 }
621
622 max_bio_size = queue_max_hw_sectors(device->rq_queue) << 9;
623 number = drbd_rs_number_requests(peer_device);
624 if (number <= 0)
625 goto requeue;
626
627 for (i = 0; i < number; i++) {
628 /* Stop generating RS requests when half of the send buffer is filled,
629 * but notify TCP that we'd like to have more space. */
630 mutex_lock(&connection->data.mutex);
631 if (connection->data.socket) {
632 struct sock *sk = connection->data.socket->sk;
633 int queued = sk->sk_wmem_queued;
634 int sndbuf = sk->sk_sndbuf;
635 if (queued > sndbuf / 2) {
636 requeue = 1;
637 if (sk->sk_socket)
638 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
639 }
640 } else
641 requeue = 1;
642 mutex_unlock(&connection->data.mutex);
643 if (requeue)
644 goto requeue;
645
646next_sector:
647 size = BM_BLOCK_SIZE;
648 bit = drbd_bm_find_next(device, device->bm_resync_fo);
649
650 if (bit == DRBD_END_OF_BITMAP) {
651 device->bm_resync_fo = drbd_bm_bits(device);
652 put_ldev(device);
653 return 0;
654 }
655
656 sector = BM_BIT_TO_SECT(bit);
657
658 if (drbd_try_rs_begin_io(peer_device, sector)) {
659 device->bm_resync_fo = bit;
660 goto requeue;
661 }
662 device->bm_resync_fo = bit + 1;
663
664 if (unlikely(drbd_bm_test_bit(device, bit) == 0)) {
665 drbd_rs_complete_io(device, sector);
666 goto next_sector;
667 }
668
669#if DRBD_MAX_BIO_SIZE > BM_BLOCK_SIZE
670 /* try to find some adjacent bits.
671 * we stop if we have already the maximum req size.
672 *
673 * Additionally always align bigger requests, in order to
674 * be prepared for all stripe sizes of software RAIDs.
675 */
676 align = 1;
677 rollback_i = i;
678 while (i < number) {
679 if (size + BM_BLOCK_SIZE > max_bio_size)
680 break;
681
682 /* Be always aligned */
683 if (sector & ((1<<(align+3))-1))
684 break;
685
686 if (discard_granularity && size == discard_granularity)
687 break;
688
689 /* do not cross extent boundaries */
690 if (((bit+1) & BM_BLOCKS_PER_BM_EXT_MASK) == 0)
691 break;
692 /* now, is it actually dirty, after all?
693 * caution, drbd_bm_test_bit is tri-state for some
694 * obscure reason; ( b == 0 ) would get the out-of-band
695 * only accidentally right because of the "oddly sized"
696 * adjustment below */
697 if (drbd_bm_test_bit(device, bit+1) != 1)
698 break;
699 bit++;
700 size += BM_BLOCK_SIZE;
701 if ((BM_BLOCK_SIZE << align) <= size)
702 align++;
703 i++;
704 }
705 /* if we merged some,
706 * reset the offset to start the next drbd_bm_find_next from */
707 if (size > BM_BLOCK_SIZE)
708 device->bm_resync_fo = bit + 1;
709#endif
710
711 /* adjust very last sectors, in case we are oddly sized */
712 if (sector + (size>>9) > capacity)
713 size = (capacity-sector)<<9;
714
715 if (device->use_csums) {
716 switch (read_for_csum(peer_device, sector, size)) {
717 case -EIO: /* Disk failure */
718 put_ldev(device);
719 return -EIO;
720 case -EAGAIN: /* allocation failed, or ldev busy */
721 drbd_rs_complete_io(device, sector);
722 device->bm_resync_fo = BM_SECT_TO_BIT(sector);
723 i = rollback_i;
724 goto requeue;
725 case 0:
726 /* everything ok */
727 break;
728 default:
729 BUG();
730 }
731 } else {
732 int err;
733
734 inc_rs_pending(peer_device);
735 err = drbd_send_drequest(peer_device,
736 size == discard_granularity ? P_RS_THIN_REQ : P_RS_DATA_REQUEST,
737 sector, size, ID_SYNCER);
738 if (err) {
739 drbd_err(device, "drbd_send_drequest() failed, aborting...\n");
740 dec_rs_pending(peer_device);
741 put_ldev(device);
742 return err;
743 }
744 }
745 }
746
747 if (device->bm_resync_fo >= drbd_bm_bits(device)) {
748 /* last syncer _request_ was sent,
749 * but the P_RS_DATA_REPLY not yet received. sync will end (and
750 * next sync group will resume), as soon as we receive the last
751 * resync data block, and the last bit is cleared.
752 * until then resync "work" is "inactive" ...
753 */
754 put_ldev(device);
755 return 0;
756 }
757
758 requeue:
759 device->rs_in_flight += (i << (BM_BLOCK_SHIFT - 9));
760 mod_timer(&device->resync_timer, jiffies + SLEEP_TIME);
761 put_ldev(device);
762 return 0;
763}
764
765static int make_ov_request(struct drbd_peer_device *peer_device, int cancel)
766{
767 struct drbd_device *device = peer_device->device;
768 int number, i, size;
769 sector_t sector;
770 const sector_t capacity = get_capacity(device->vdisk);
771 bool stop_sector_reached = false;
772
773 if (unlikely(cancel))
774 return 1;
775
776 number = drbd_rs_number_requests(peer_device);
777
778 sector = device->ov_position;
779 for (i = 0; i < number; i++) {
780 if (sector >= capacity)
781 return 1;
782
783 /* We check for "finished" only in the reply path:
784 * w_e_end_ov_reply().
785 * We need to send at least one request out. */
786 stop_sector_reached = i > 0
787 && verify_can_do_stop_sector(device)
788 && sector >= device->ov_stop_sector;
789 if (stop_sector_reached)
790 break;
791
792 size = BM_BLOCK_SIZE;
793
794 if (drbd_try_rs_begin_io(peer_device, sector)) {
795 device->ov_position = sector;
796 goto requeue;
797 }
798
799 if (sector + (size>>9) > capacity)
800 size = (capacity-sector)<<9;
801
802 inc_rs_pending(peer_device);
803 if (drbd_send_ov_request(first_peer_device(device), sector, size)) {
804 dec_rs_pending(peer_device);
805 return 0;
806 }
807 sector += BM_SECT_PER_BIT;
808 }
809 device->ov_position = sector;
810
811 requeue:
812 device->rs_in_flight += (i << (BM_BLOCK_SHIFT - 9));
813 if (i == 0 || !stop_sector_reached)
814 mod_timer(&device->resync_timer, jiffies + SLEEP_TIME);
815 return 1;
816}
817
818int w_ov_finished(struct drbd_work *w, int cancel)
819{
820 struct drbd_device_work *dw =
821 container_of(w, struct drbd_device_work, w);
822 struct drbd_device *device = dw->device;
823 kfree(dw);
824 ov_out_of_sync_print(first_peer_device(device));
825 drbd_resync_finished(first_peer_device(device));
826
827 return 0;
828}
829
830static int w_resync_finished(struct drbd_work *w, int cancel)
831{
832 struct drbd_device_work *dw =
833 container_of(w, struct drbd_device_work, w);
834 struct drbd_device *device = dw->device;
835 kfree(dw);
836
837 drbd_resync_finished(first_peer_device(device));
838
839 return 0;
840}
841
842static void ping_peer(struct drbd_device *device)
843{
844 struct drbd_connection *connection = first_peer_device(device)->connection;
845
846 clear_bit(GOT_PING_ACK, &connection->flags);
847 request_ping(connection);
848 wait_event(connection->ping_wait,
849 test_bit(GOT_PING_ACK, &connection->flags) || device->state.conn < C_CONNECTED);
850}
851
852int drbd_resync_finished(struct drbd_peer_device *peer_device)
853{
854 struct drbd_device *device = peer_device->device;
855 struct drbd_connection *connection = peer_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 = PFN_UP(peer_req->i.size);
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 (drbd_ratelimit())
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(peer_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 (drbd_ratelimit())
1143 drbd_err(device, "Not sending RSDataReply, "
1144 "partner DISKLESS!\n");
1145 err = 0;
1146 }
1147 } else {
1148 if (drbd_ratelimit())
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(peer_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(peer_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(peer_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 (drbd_ratelimit())
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(peer_device);
1265 err = drbd_send_drequest_csum(peer_device, sector, size, digest, digest_size, P_OV_REPLY);
1266 if (err)
1267 dec_rs_pending(peer_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_peer_device *peer_device, sector_t sector, int size)
1278{
1279 struct drbd_device *device = peer_device->device;
1280 if (device->ov_last_oos_start + device->ov_last_oos_size == sector) {
1281 device->ov_last_oos_size += size>>9;
1282 } else {
1283 device->ov_last_oos_start = sector;
1284 device->ov_last_oos_size = size>>9;
1285 }
1286 drbd_set_out_of_sync(peer_device, sector, size);
1287}
1288
1289int w_e_end_ov_reply(struct drbd_work *w, int cancel)
1290{
1291 struct drbd_peer_request *peer_req = container_of(w, struct drbd_peer_request, w);
1292 struct drbd_peer_device *peer_device = peer_req->peer_device;
1293 struct drbd_device *device = peer_device->device;
1294 struct digest_info *di;
1295 void *digest;
1296 sector_t sector = peer_req->i.sector;
1297 unsigned int size = peer_req->i.size;
1298 int digest_size;
1299 int err, eq = 0;
1300 bool stop_sector_reached = false;
1301
1302 if (unlikely(cancel)) {
1303 drbd_free_peer_req(device, peer_req);
1304 dec_unacked(device);
1305 return 0;
1306 }
1307
1308 /* after "cancel", because after drbd_disconnect/drbd_rs_cancel_all
1309 * the resync lru has been cleaned up already */
1310 if (get_ldev(device)) {
1311 drbd_rs_complete_io(device, peer_req->i.sector);
1312 put_ldev(device);
1313 }
1314
1315 di = peer_req->digest;
1316
1317 if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) {
1318 digest_size = crypto_shash_digestsize(peer_device->connection->verify_tfm);
1319 digest = kmalloc(digest_size, GFP_NOIO);
1320 if (digest) {
1321 drbd_csum_ee(peer_device->connection->verify_tfm, peer_req, digest);
1322
1323 D_ASSERT(device, digest_size == di->digest_size);
1324 eq = !memcmp(digest, di->digest, digest_size);
1325 kfree(digest);
1326 }
1327 }
1328
1329 /* Free peer_req and pages before send.
1330 * In case we block on congestion, we could otherwise run into
1331 * some distributed deadlock, if the other side blocks on
1332 * congestion as well, because our receiver blocks in
1333 * drbd_alloc_pages due to pp_in_use > max_buffers. */
1334 drbd_free_peer_req(device, peer_req);
1335 if (!eq)
1336 drbd_ov_out_of_sync_found(peer_device, sector, size);
1337 else
1338 ov_out_of_sync_print(peer_device);
1339
1340 err = drbd_send_ack_ex(peer_device, P_OV_RESULT, sector, size,
1341 eq ? ID_IN_SYNC : ID_OUT_OF_SYNC);
1342
1343 dec_unacked(device);
1344
1345 --device->ov_left;
1346
1347 /* let's advance progress step marks only for every other megabyte */
1348 if ((device->ov_left & 0x200) == 0x200)
1349 drbd_advance_rs_marks(peer_device, device->ov_left);
1350
1351 stop_sector_reached = verify_can_do_stop_sector(device) &&
1352 (sector + (size>>9)) >= device->ov_stop_sector;
1353
1354 if (device->ov_left == 0 || stop_sector_reached) {
1355 ov_out_of_sync_print(peer_device);
1356 drbd_resync_finished(peer_device);
1357 }
1358
1359 return err;
1360}
1361
1362/* FIXME
1363 * We need to track the number of pending barrier acks,
1364 * and to be able to wait for them.
1365 * See also comment in drbd_adm_attach before drbd_suspend_io.
1366 */
1367static int drbd_send_barrier(struct drbd_connection *connection)
1368{
1369 struct p_barrier *p;
1370 struct drbd_socket *sock;
1371
1372 sock = &connection->data;
1373 p = conn_prepare_command(connection, sock);
1374 if (!p)
1375 return -EIO;
1376 p->barrier = connection->send.current_epoch_nr;
1377 p->pad = 0;
1378 connection->send.current_epoch_writes = 0;
1379 connection->send.last_sent_barrier_jif = jiffies;
1380
1381 return conn_send_command(connection, sock, P_BARRIER, sizeof(*p), NULL, 0);
1382}
1383
1384static int pd_send_unplug_remote(struct drbd_peer_device *pd)
1385{
1386 struct drbd_socket *sock = &pd->connection->data;
1387 if (!drbd_prepare_command(pd, sock))
1388 return -EIO;
1389 return drbd_send_command(pd, sock, P_UNPLUG_REMOTE, 0, NULL, 0);
1390}
1391
1392int w_send_write_hint(struct drbd_work *w, int cancel)
1393{
1394 struct drbd_device *device =
1395 container_of(w, struct drbd_device, unplug_work);
1396
1397 if (cancel)
1398 return 0;
1399 return pd_send_unplug_remote(first_peer_device(device));
1400}
1401
1402static void re_init_if_first_write(struct drbd_connection *connection, unsigned int epoch)
1403{
1404 if (!connection->send.seen_any_write_yet) {
1405 connection->send.seen_any_write_yet = true;
1406 connection->send.current_epoch_nr = epoch;
1407 connection->send.current_epoch_writes = 0;
1408 connection->send.last_sent_barrier_jif = jiffies;
1409 }
1410}
1411
1412static void maybe_send_barrier(struct drbd_connection *connection, unsigned int epoch)
1413{
1414 /* re-init if first write on this connection */
1415 if (!connection->send.seen_any_write_yet)
1416 return;
1417 if (connection->send.current_epoch_nr != epoch) {
1418 if (connection->send.current_epoch_writes)
1419 drbd_send_barrier(connection);
1420 connection->send.current_epoch_nr = epoch;
1421 }
1422}
1423
1424int w_send_out_of_sync(struct drbd_work *w, int cancel)
1425{
1426 struct drbd_request *req = container_of(w, struct drbd_request, w);
1427 struct drbd_device *device = req->device;
1428 struct drbd_peer_device *const peer_device = first_peer_device(device);
1429 struct drbd_connection *const connection = peer_device->connection;
1430 int err;
1431
1432 if (unlikely(cancel)) {
1433 req_mod(req, SEND_CANCELED, peer_device);
1434 return 0;
1435 }
1436 req->pre_send_jif = jiffies;
1437
1438 /* this time, no connection->send.current_epoch_writes++;
1439 * If it was sent, it was the closing barrier for the last
1440 * replicated epoch, before we went into AHEAD mode.
1441 * No more barriers will be sent, until we leave AHEAD mode again. */
1442 maybe_send_barrier(connection, req->epoch);
1443
1444 err = drbd_send_out_of_sync(peer_device, req);
1445 req_mod(req, OOS_HANDED_TO_NETWORK, peer_device);
1446
1447 return err;
1448}
1449
1450/**
1451 * w_send_dblock() - Worker callback to send a P_DATA packet in order to mirror a write request
1452 * @w: work object.
1453 * @cancel: The connection will be closed anyways
1454 */
1455int w_send_dblock(struct drbd_work *w, int cancel)
1456{
1457 struct drbd_request *req = container_of(w, struct drbd_request, w);
1458 struct drbd_device *device = req->device;
1459 struct drbd_peer_device *const peer_device = first_peer_device(device);
1460 struct drbd_connection *connection = peer_device->connection;
1461 bool do_send_unplug = req->rq_state & RQ_UNPLUG;
1462 int err;
1463
1464 if (unlikely(cancel)) {
1465 req_mod(req, SEND_CANCELED, peer_device);
1466 return 0;
1467 }
1468 req->pre_send_jif = jiffies;
1469
1470 re_init_if_first_write(connection, req->epoch);
1471 maybe_send_barrier(connection, req->epoch);
1472 connection->send.current_epoch_writes++;
1473
1474 err = drbd_send_dblock(peer_device, req);
1475 req_mod(req, err ? SEND_FAILED : HANDED_OVER_TO_NETWORK, peer_device);
1476
1477 if (do_send_unplug && !err)
1478 pd_send_unplug_remote(peer_device);
1479
1480 return err;
1481}
1482
1483/**
1484 * w_send_read_req() - Worker callback to send a read request (P_DATA_REQUEST) packet
1485 * @w: work object.
1486 * @cancel: The connection will be closed anyways
1487 */
1488int w_send_read_req(struct drbd_work *w, int cancel)
1489{
1490 struct drbd_request *req = container_of(w, struct drbd_request, w);
1491 struct drbd_device *device = req->device;
1492 struct drbd_peer_device *const peer_device = first_peer_device(device);
1493 struct drbd_connection *connection = peer_device->connection;
1494 bool do_send_unplug = req->rq_state & RQ_UNPLUG;
1495 int err;
1496
1497 if (unlikely(cancel)) {
1498 req_mod(req, SEND_CANCELED, peer_device);
1499 return 0;
1500 }
1501 req->pre_send_jif = jiffies;
1502
1503 /* Even read requests may close a write epoch,
1504 * if there was any yet. */
1505 maybe_send_barrier(connection, req->epoch);
1506
1507 err = drbd_send_drequest(peer_device, P_DATA_REQUEST, req->i.sector, req->i.size,
1508 (unsigned long)req);
1509
1510 req_mod(req, err ? SEND_FAILED : HANDED_OVER_TO_NETWORK, peer_device);
1511
1512 if (do_send_unplug && !err)
1513 pd_send_unplug_remote(peer_device);
1514
1515 return err;
1516}
1517
1518int w_restart_disk_io(struct drbd_work *w, int cancel)
1519{
1520 struct drbd_request *req = container_of(w, struct drbd_request, w);
1521 struct drbd_device *device = req->device;
1522
1523 if (bio_data_dir(req->master_bio) == WRITE && req->rq_state & RQ_IN_ACT_LOG)
1524 drbd_al_begin_io(device, &req->i);
1525
1526 req->private_bio = bio_alloc_clone(device->ldev->backing_bdev,
1527 req->master_bio, GFP_NOIO,
1528 &drbd_io_bio_set);
1529 req->private_bio->bi_private = req;
1530 req->private_bio->bi_end_io = drbd_request_endio;
1531 submit_bio_noacct(req->private_bio);
1532
1533 return 0;
1534}
1535
1536static int _drbd_may_sync_now(struct drbd_device *device)
1537{
1538 struct drbd_device *odev = device;
1539 int resync_after;
1540
1541 while (1) {
1542 if (!odev->ldev || odev->state.disk == D_DISKLESS)
1543 return 1;
1544 rcu_read_lock();
1545 resync_after = rcu_dereference(odev->ldev->disk_conf)->resync_after;
1546 rcu_read_unlock();
1547 if (resync_after == -1)
1548 return 1;
1549 odev = minor_to_device(resync_after);
1550 if (!odev)
1551 return 1;
1552 if ((odev->state.conn >= C_SYNC_SOURCE &&
1553 odev->state.conn <= C_PAUSED_SYNC_T) ||
1554 odev->state.aftr_isp || odev->state.peer_isp ||
1555 odev->state.user_isp)
1556 return 0;
1557 }
1558}
1559
1560/**
1561 * drbd_pause_after() - Pause resync on all devices that may not resync now
1562 * @device: DRBD device.
1563 *
1564 * Called from process context only (admin command and after_state_ch).
1565 */
1566static bool drbd_pause_after(struct drbd_device *device)
1567{
1568 bool changed = false;
1569 struct drbd_device *odev;
1570 int i;
1571
1572 rcu_read_lock();
1573 idr_for_each_entry(&drbd_devices, odev, i) {
1574 if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS)
1575 continue;
1576 if (!_drbd_may_sync_now(odev) &&
1577 _drbd_set_state(_NS(odev, aftr_isp, 1),
1578 CS_HARD, NULL) != SS_NOTHING_TO_DO)
1579 changed = true;
1580 }
1581 rcu_read_unlock();
1582
1583 return changed;
1584}
1585
1586/**
1587 * drbd_resume_next() - Resume resync on all devices that may resync now
1588 * @device: DRBD device.
1589 *
1590 * Called from process context only (admin command and worker).
1591 */
1592static bool drbd_resume_next(struct drbd_device *device)
1593{
1594 bool changed = false;
1595 struct drbd_device *odev;
1596 int i;
1597
1598 rcu_read_lock();
1599 idr_for_each_entry(&drbd_devices, odev, i) {
1600 if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS)
1601 continue;
1602 if (odev->state.aftr_isp) {
1603 if (_drbd_may_sync_now(odev) &&
1604 _drbd_set_state(_NS(odev, aftr_isp, 0),
1605 CS_HARD, NULL) != SS_NOTHING_TO_DO)
1606 changed = true;
1607 }
1608 }
1609 rcu_read_unlock();
1610 return changed;
1611}
1612
1613void resume_next_sg(struct drbd_device *device)
1614{
1615 lock_all_resources();
1616 drbd_resume_next(device);
1617 unlock_all_resources();
1618}
1619
1620void suspend_other_sg(struct drbd_device *device)
1621{
1622 lock_all_resources();
1623 drbd_pause_after(device);
1624 unlock_all_resources();
1625}
1626
1627/* caller must lock_all_resources() */
1628enum drbd_ret_code drbd_resync_after_valid(struct drbd_device *device, int o_minor)
1629{
1630 struct drbd_device *odev;
1631 int resync_after;
1632
1633 if (o_minor == -1)
1634 return NO_ERROR;
1635 if (o_minor < -1 || o_minor > MINORMASK)
1636 return ERR_RESYNC_AFTER;
1637
1638 /* check for loops */
1639 odev = minor_to_device(o_minor);
1640 while (1) {
1641 if (odev == device)
1642 return ERR_RESYNC_AFTER_CYCLE;
1643
1644 /* You are free to depend on diskless, non-existing,
1645 * or not yet/no longer existing minors.
1646 * We only reject dependency loops.
1647 * We cannot follow the dependency chain beyond a detached or
1648 * missing minor.
1649 */
1650 if (!odev || !odev->ldev || odev->state.disk == D_DISKLESS)
1651 return NO_ERROR;
1652
1653 rcu_read_lock();
1654 resync_after = rcu_dereference(odev->ldev->disk_conf)->resync_after;
1655 rcu_read_unlock();
1656 /* dependency chain ends here, no cycles. */
1657 if (resync_after == -1)
1658 return NO_ERROR;
1659
1660 /* follow the dependency chain */
1661 odev = minor_to_device(resync_after);
1662 }
1663}
1664
1665/* caller must lock_all_resources() */
1666void drbd_resync_after_changed(struct drbd_device *device)
1667{
1668 int changed;
1669
1670 do {
1671 changed = drbd_pause_after(device);
1672 changed |= drbd_resume_next(device);
1673 } while (changed);
1674}
1675
1676void drbd_rs_controller_reset(struct drbd_peer_device *peer_device)
1677{
1678 struct drbd_device *device = peer_device->device;
1679 struct gendisk *disk = device->ldev->backing_bdev->bd_disk;
1680 struct fifo_buffer *plan;
1681
1682 atomic_set(&device->rs_sect_in, 0);
1683 atomic_set(&device->rs_sect_ev, 0);
1684 device->rs_in_flight = 0;
1685 device->rs_last_events =
1686 (int)part_stat_read_accum(disk->part0, sectors);
1687
1688 /* Updating the RCU protected object in place is necessary since
1689 this function gets called from atomic context.
1690 It is valid since all other updates also lead to an completely
1691 empty fifo */
1692 rcu_read_lock();
1693 plan = rcu_dereference(device->rs_plan_s);
1694 plan->total = 0;
1695 fifo_set(plan, 0);
1696 rcu_read_unlock();
1697}
1698
1699void start_resync_timer_fn(struct timer_list *t)
1700{
1701 struct drbd_device *device = from_timer(device, t, start_resync_timer);
1702 drbd_device_post_work(device, RS_START);
1703}
1704
1705static void do_start_resync(struct drbd_device *device)
1706{
1707 if (atomic_read(&device->unacked_cnt) || atomic_read(&device->rs_pending_cnt)) {
1708 drbd_warn(device, "postponing start_resync ...\n");
1709 device->start_resync_timer.expires = jiffies + HZ/10;
1710 add_timer(&device->start_resync_timer);
1711 return;
1712 }
1713
1714 drbd_start_resync(device, C_SYNC_SOURCE);
1715 clear_bit(AHEAD_TO_SYNC_SOURCE, &device->flags);
1716}
1717
1718static bool use_checksum_based_resync(struct drbd_connection *connection, struct drbd_device *device)
1719{
1720 bool csums_after_crash_only;
1721 rcu_read_lock();
1722 csums_after_crash_only = rcu_dereference(connection->net_conf)->csums_after_crash_only;
1723 rcu_read_unlock();
1724 return connection->agreed_pro_version >= 89 && /* supported? */
1725 connection->csums_tfm && /* configured? */
1726 (csums_after_crash_only == false /* use for each resync? */
1727 || test_bit(CRASHED_PRIMARY, &device->flags)); /* or only after Primary crash? */
1728}
1729
1730/**
1731 * drbd_start_resync() - Start the resync process
1732 * @device: DRBD device.
1733 * @side: Either C_SYNC_SOURCE or C_SYNC_TARGET
1734 *
1735 * This function might bring you directly into one of the
1736 * C_PAUSED_SYNC_* states.
1737 */
1738void drbd_start_resync(struct drbd_device *device, enum drbd_conns side)
1739{
1740 struct drbd_peer_device *peer_device = first_peer_device(device);
1741 struct drbd_connection *connection = peer_device ? peer_device->connection : NULL;
1742 union drbd_state ns;
1743 int r;
1744
1745 if (device->state.conn >= C_SYNC_SOURCE && device->state.conn < C_AHEAD) {
1746 drbd_err(device, "Resync already running!\n");
1747 return;
1748 }
1749
1750 if (!connection) {
1751 drbd_err(device, "No connection to peer, aborting!\n");
1752 return;
1753 }
1754
1755 if (!test_bit(B_RS_H_DONE, &device->flags)) {
1756 if (side == C_SYNC_TARGET) {
1757 /* Since application IO was locked out during C_WF_BITMAP_T and
1758 C_WF_SYNC_UUID we are still unmodified. Before going to C_SYNC_TARGET
1759 we check that we might make the data inconsistent. */
1760 r = drbd_khelper(device, "before-resync-target");
1761 r = (r >> 8) & 0xff;
1762 if (r > 0) {
1763 drbd_info(device, "before-resync-target handler returned %d, "
1764 "dropping connection.\n", r);
1765 conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
1766 return;
1767 }
1768 } else /* C_SYNC_SOURCE */ {
1769 r = drbd_khelper(device, "before-resync-source");
1770 r = (r >> 8) & 0xff;
1771 if (r > 0) {
1772 if (r == 3) {
1773 drbd_info(device, "before-resync-source handler returned %d, "
1774 "ignoring. Old userland tools?", r);
1775 } else {
1776 drbd_info(device, "before-resync-source handler returned %d, "
1777 "dropping connection.\n", r);
1778 conn_request_state(connection,
1779 NS(conn, C_DISCONNECTING), CS_HARD);
1780 return;
1781 }
1782 }
1783 }
1784 }
1785
1786 if (current == connection->worker.task) {
1787 /* The worker should not sleep waiting for state_mutex,
1788 that can take long */
1789 if (!mutex_trylock(device->state_mutex)) {
1790 set_bit(B_RS_H_DONE, &device->flags);
1791 device->start_resync_timer.expires = jiffies + HZ/5;
1792 add_timer(&device->start_resync_timer);
1793 return;
1794 }
1795 } else {
1796 mutex_lock(device->state_mutex);
1797 }
1798
1799 lock_all_resources();
1800 clear_bit(B_RS_H_DONE, &device->flags);
1801 /* Did some connection breakage or IO error race with us? */
1802 if (device->state.conn < C_CONNECTED
1803 || !get_ldev_if_state(device, D_NEGOTIATING)) {
1804 unlock_all_resources();
1805 goto out;
1806 }
1807
1808 ns = drbd_read_state(device);
1809
1810 ns.aftr_isp = !_drbd_may_sync_now(device);
1811
1812 ns.conn = side;
1813
1814 if (side == C_SYNC_TARGET)
1815 ns.disk = D_INCONSISTENT;
1816 else /* side == C_SYNC_SOURCE */
1817 ns.pdsk = D_INCONSISTENT;
1818
1819 r = _drbd_set_state(device, ns, CS_VERBOSE, NULL);
1820 ns = drbd_read_state(device);
1821
1822 if (ns.conn < C_CONNECTED)
1823 r = SS_UNKNOWN_ERROR;
1824
1825 if (r == SS_SUCCESS) {
1826 unsigned long tw = drbd_bm_total_weight(device);
1827 unsigned long now = jiffies;
1828 int i;
1829
1830 device->rs_failed = 0;
1831 device->rs_paused = 0;
1832 device->rs_same_csum = 0;
1833 device->rs_last_sect_ev = 0;
1834 device->rs_total = tw;
1835 device->rs_start = now;
1836 for (i = 0; i < DRBD_SYNC_MARKS; i++) {
1837 device->rs_mark_left[i] = tw;
1838 device->rs_mark_time[i] = now;
1839 }
1840 drbd_pause_after(device);
1841 /* Forget potentially stale cached per resync extent bit-counts.
1842 * Open coded drbd_rs_cancel_all(device), we already have IRQs
1843 * disabled, and know the disk state is ok. */
1844 spin_lock(&device->al_lock);
1845 lc_reset(device->resync);
1846 device->resync_locked = 0;
1847 device->resync_wenr = LC_FREE;
1848 spin_unlock(&device->al_lock);
1849 }
1850 unlock_all_resources();
1851
1852 if (r == SS_SUCCESS) {
1853 wake_up(&device->al_wait); /* for lc_reset() above */
1854 /* reset rs_last_bcast when a resync or verify is started,
1855 * to deal with potential jiffies wrap. */
1856 device->rs_last_bcast = jiffies - HZ;
1857
1858 drbd_info(device, "Began resync as %s (will sync %lu KB [%lu bits set]).\n",
1859 drbd_conn_str(ns.conn),
1860 (unsigned long) device->rs_total << (BM_BLOCK_SHIFT-10),
1861 (unsigned long) device->rs_total);
1862 if (side == C_SYNC_TARGET) {
1863 device->bm_resync_fo = 0;
1864 device->use_csums = use_checksum_based_resync(connection, device);
1865 } else {
1866 device->use_csums = false;
1867 }
1868
1869 /* Since protocol 96, we must serialize drbd_gen_and_send_sync_uuid
1870 * with w_send_oos, or the sync target will get confused as to
1871 * how much bits to resync. We cannot do that always, because for an
1872 * empty resync and protocol < 95, we need to do it here, as we call
1873 * drbd_resync_finished from here in that case.
1874 * We drbd_gen_and_send_sync_uuid here for protocol < 96,
1875 * and from after_state_ch otherwise. */
1876 if (side == C_SYNC_SOURCE && connection->agreed_pro_version < 96)
1877 drbd_gen_and_send_sync_uuid(peer_device);
1878
1879 if (connection->agreed_pro_version < 95 && device->rs_total == 0) {
1880 /* This still has a race (about when exactly the peers
1881 * detect connection loss) that can lead to a full sync
1882 * on next handshake. In 8.3.9 we fixed this with explicit
1883 * resync-finished notifications, but the fix
1884 * introduces a protocol change. Sleeping for some
1885 * time longer than the ping interval + timeout on the
1886 * SyncSource, to give the SyncTarget the chance to
1887 * detect connection loss, then waiting for a ping
1888 * response (implicit in drbd_resync_finished) reduces
1889 * the race considerably, but does not solve it. */
1890 if (side == C_SYNC_SOURCE) {
1891 struct net_conf *nc;
1892 int timeo;
1893
1894 rcu_read_lock();
1895 nc = rcu_dereference(connection->net_conf);
1896 timeo = nc->ping_int * HZ + nc->ping_timeo * HZ / 9;
1897 rcu_read_unlock();
1898 schedule_timeout_interruptible(timeo);
1899 }
1900 drbd_resync_finished(peer_device);
1901 }
1902
1903 drbd_rs_controller_reset(peer_device);
1904 /* ns.conn may already be != device->state.conn,
1905 * we may have been paused in between, or become paused until
1906 * the timer triggers.
1907 * No matter, that is handled in resync_timer_fn() */
1908 if (ns.conn == C_SYNC_TARGET)
1909 mod_timer(&device->resync_timer, jiffies);
1910
1911 drbd_md_sync(device);
1912 }
1913 put_ldev(device);
1914out:
1915 mutex_unlock(device->state_mutex);
1916}
1917
1918static void update_on_disk_bitmap(struct drbd_peer_device *peer_device, bool resync_done)
1919{
1920 struct drbd_device *device = peer_device->device;
1921 struct sib_info sib = { .sib_reason = SIB_SYNC_PROGRESS, };
1922 device->rs_last_bcast = jiffies;
1923
1924 if (!get_ldev(device))
1925 return;
1926
1927 drbd_bm_write_lazy(device, 0);
1928 if (resync_done && is_sync_state(device->state.conn))
1929 drbd_resync_finished(peer_device);
1930
1931 drbd_bcast_event(device, &sib);
1932 /* update timestamp, in case it took a while to write out stuff */
1933 device->rs_last_bcast = jiffies;
1934 put_ldev(device);
1935}
1936
1937static void drbd_ldev_destroy(struct drbd_device *device)
1938{
1939 lc_destroy(device->resync);
1940 device->resync = NULL;
1941 lc_destroy(device->act_log);
1942 device->act_log = NULL;
1943
1944 __acquire(local);
1945 drbd_backing_dev_free(device, device->ldev);
1946 device->ldev = NULL;
1947 __release(local);
1948
1949 clear_bit(GOING_DISKLESS, &device->flags);
1950 wake_up(&device->misc_wait);
1951}
1952
1953static void go_diskless(struct drbd_device *device)
1954{
1955 struct drbd_peer_device *peer_device = first_peer_device(device);
1956 D_ASSERT(device, device->state.disk == D_FAILED);
1957 /* we cannot assert local_cnt == 0 here, as get_ldev_if_state will
1958 * inc/dec it frequently. Once we are D_DISKLESS, no one will touch
1959 * the protected members anymore, though, so once put_ldev reaches zero
1960 * again, it will be safe to free them. */
1961
1962 /* Try to write changed bitmap pages, read errors may have just
1963 * set some bits outside the area covered by the activity log.
1964 *
1965 * If we have an IO error during the bitmap writeout,
1966 * we will want a full sync next time, just in case.
1967 * (Do we want a specific meta data flag for this?)
1968 *
1969 * If that does not make it to stable storage either,
1970 * we cannot do anything about that anymore.
1971 *
1972 * We still need to check if both bitmap and ldev are present, we may
1973 * end up here after a failed attach, before ldev was even assigned.
1974 */
1975 if (device->bitmap && device->ldev) {
1976 /* An interrupted resync or similar is allowed to recounts bits
1977 * while we detach.
1978 * Any modifications would not be expected anymore, though.
1979 */
1980 if (drbd_bitmap_io_from_worker(device, drbd_bm_write,
1981 "detach", BM_LOCKED_TEST_ALLOWED, peer_device)) {
1982 if (test_bit(WAS_READ_ERROR, &device->flags)) {
1983 drbd_md_set_flag(device, MDF_FULL_SYNC);
1984 drbd_md_sync(device);
1985 }
1986 }
1987 }
1988
1989 drbd_force_state(device, NS(disk, D_DISKLESS));
1990}
1991
1992static int do_md_sync(struct drbd_device *device)
1993{
1994 drbd_warn(device, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
1995 drbd_md_sync(device);
1996 return 0;
1997}
1998
1999/* only called from drbd_worker thread, no locking */
2000void __update_timing_details(
2001 struct drbd_thread_timing_details *tdp,
2002 unsigned int *cb_nr,
2003 void *cb,
2004 const char *fn, const unsigned int line)
2005{
2006 unsigned int i = *cb_nr % DRBD_THREAD_DETAILS_HIST;
2007 struct drbd_thread_timing_details *td = tdp + i;
2008
2009 td->start_jif = jiffies;
2010 td->cb_addr = cb;
2011 td->caller_fn = fn;
2012 td->line = line;
2013 td->cb_nr = *cb_nr;
2014
2015 i = (i+1) % DRBD_THREAD_DETAILS_HIST;
2016 td = tdp + i;
2017 memset(td, 0, sizeof(*td));
2018
2019 ++(*cb_nr);
2020}
2021
2022static void do_device_work(struct drbd_device *device, const unsigned long todo)
2023{
2024 if (test_bit(MD_SYNC, &todo))
2025 do_md_sync(device);
2026 if (test_bit(RS_DONE, &todo) ||
2027 test_bit(RS_PROGRESS, &todo))
2028 update_on_disk_bitmap(first_peer_device(device), test_bit(RS_DONE, &todo));
2029 if (test_bit(GO_DISKLESS, &todo))
2030 go_diskless(device);
2031 if (test_bit(DESTROY_DISK, &todo))
2032 drbd_ldev_destroy(device);
2033 if (test_bit(RS_START, &todo))
2034 do_start_resync(device);
2035}
2036
2037#define DRBD_DEVICE_WORK_MASK \
2038 ((1UL << GO_DISKLESS) \
2039 |(1UL << DESTROY_DISK) \
2040 |(1UL << MD_SYNC) \
2041 |(1UL << RS_START) \
2042 |(1UL << RS_PROGRESS) \
2043 |(1UL << RS_DONE) \
2044 )
2045
2046static unsigned long get_work_bits(unsigned long *flags)
2047{
2048 unsigned long old, new;
2049 do {
2050 old = *flags;
2051 new = old & ~DRBD_DEVICE_WORK_MASK;
2052 } while (cmpxchg(flags, old, new) != old);
2053 return old & DRBD_DEVICE_WORK_MASK;
2054}
2055
2056static void do_unqueued_work(struct drbd_connection *connection)
2057{
2058 struct drbd_peer_device *peer_device;
2059 int vnr;
2060
2061 rcu_read_lock();
2062 idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
2063 struct drbd_device *device = peer_device->device;
2064 unsigned long todo = get_work_bits(&device->flags);
2065 if (!todo)
2066 continue;
2067
2068 kref_get(&device->kref);
2069 rcu_read_unlock();
2070 do_device_work(device, todo);
2071 kref_put(&device->kref, drbd_destroy_device);
2072 rcu_read_lock();
2073 }
2074 rcu_read_unlock();
2075}
2076
2077static bool dequeue_work_batch(struct drbd_work_queue *queue, struct list_head *work_list)
2078{
2079 spin_lock_irq(&queue->q_lock);
2080 list_splice_tail_init(&queue->q, work_list);
2081 spin_unlock_irq(&queue->q_lock);
2082 return !list_empty(work_list);
2083}
2084
2085static void wait_for_work(struct drbd_connection *connection, struct list_head *work_list)
2086{
2087 DEFINE_WAIT(wait);
2088 struct net_conf *nc;
2089 int uncork, cork;
2090
2091 dequeue_work_batch(&connection->sender_work, work_list);
2092 if (!list_empty(work_list))
2093 return;
2094
2095 /* Still nothing to do?
2096 * Maybe we still need to close the current epoch,
2097 * even if no new requests are queued yet.
2098 *
2099 * Also, poke TCP, just in case.
2100 * Then wait for new work (or signal). */
2101 rcu_read_lock();
2102 nc = rcu_dereference(connection->net_conf);
2103 uncork = nc ? nc->tcp_cork : 0;
2104 rcu_read_unlock();
2105 if (uncork) {
2106 mutex_lock(&connection->data.mutex);
2107 if (connection->data.socket)
2108 tcp_sock_set_cork(connection->data.socket->sk, false);
2109 mutex_unlock(&connection->data.mutex);
2110 }
2111
2112 for (;;) {
2113 int send_barrier;
2114 prepare_to_wait(&connection->sender_work.q_wait, &wait, TASK_INTERRUPTIBLE);
2115 spin_lock_irq(&connection->resource->req_lock);
2116 spin_lock(&connection->sender_work.q_lock); /* FIXME get rid of this one? */
2117 if (!list_empty(&connection->sender_work.q))
2118 list_splice_tail_init(&connection->sender_work.q, work_list);
2119 spin_unlock(&connection->sender_work.q_lock); /* FIXME get rid of this one? */
2120 if (!list_empty(work_list) || signal_pending(current)) {
2121 spin_unlock_irq(&connection->resource->req_lock);
2122 break;
2123 }
2124
2125 /* We found nothing new to do, no to-be-communicated request,
2126 * no other work item. We may still need to close the last
2127 * epoch. Next incoming request epoch will be connection ->
2128 * current transfer log epoch number. If that is different
2129 * from the epoch of the last request we communicated, it is
2130 * safe to send the epoch separating barrier now.
2131 */
2132 send_barrier =
2133 atomic_read(&connection->current_tle_nr) !=
2134 connection->send.current_epoch_nr;
2135 spin_unlock_irq(&connection->resource->req_lock);
2136
2137 if (send_barrier)
2138 maybe_send_barrier(connection,
2139 connection->send.current_epoch_nr + 1);
2140
2141 if (test_bit(DEVICE_WORK_PENDING, &connection->flags))
2142 break;
2143
2144 /* drbd_send() may have called flush_signals() */
2145 if (get_t_state(&connection->worker) != RUNNING)
2146 break;
2147
2148 schedule();
2149 /* may be woken up for other things but new work, too,
2150 * e.g. if the current epoch got closed.
2151 * In which case we send the barrier above. */
2152 }
2153 finish_wait(&connection->sender_work.q_wait, &wait);
2154
2155 /* someone may have changed the config while we have been waiting above. */
2156 rcu_read_lock();
2157 nc = rcu_dereference(connection->net_conf);
2158 cork = nc ? nc->tcp_cork : 0;
2159 rcu_read_unlock();
2160 mutex_lock(&connection->data.mutex);
2161 if (connection->data.socket) {
2162 if (cork)
2163 tcp_sock_set_cork(connection->data.socket->sk, true);
2164 else if (!uncork)
2165 tcp_sock_set_cork(connection->data.socket->sk, false);
2166 }
2167 mutex_unlock(&connection->data.mutex);
2168}
2169
2170int drbd_worker(struct drbd_thread *thi)
2171{
2172 struct drbd_connection *connection = thi->connection;
2173 struct drbd_work *w = NULL;
2174 struct drbd_peer_device *peer_device;
2175 LIST_HEAD(work_list);
2176 int vnr;
2177
2178 while (get_t_state(thi) == RUNNING) {
2179 drbd_thread_current_set_cpu(thi);
2180
2181 if (list_empty(&work_list)) {
2182 update_worker_timing_details(connection, wait_for_work);
2183 wait_for_work(connection, &work_list);
2184 }
2185
2186 if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) {
2187 update_worker_timing_details(connection, do_unqueued_work);
2188 do_unqueued_work(connection);
2189 }
2190
2191 if (signal_pending(current)) {
2192 flush_signals(current);
2193 if (get_t_state(thi) == RUNNING) {
2194 drbd_warn(connection, "Worker got an unexpected signal\n");
2195 continue;
2196 }
2197 break;
2198 }
2199
2200 if (get_t_state(thi) != RUNNING)
2201 break;
2202
2203 if (!list_empty(&work_list)) {
2204 w = list_first_entry(&work_list, struct drbd_work, list);
2205 list_del_init(&w->list);
2206 update_worker_timing_details(connection, w->cb);
2207 if (w->cb(w, connection->cstate < C_WF_REPORT_PARAMS) == 0)
2208 continue;
2209 if (connection->cstate >= C_WF_REPORT_PARAMS)
2210 conn_request_state(connection, NS(conn, C_NETWORK_FAILURE), CS_HARD);
2211 }
2212 }
2213
2214 do {
2215 if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) {
2216 update_worker_timing_details(connection, do_unqueued_work);
2217 do_unqueued_work(connection);
2218 }
2219 if (!list_empty(&work_list)) {
2220 w = list_first_entry(&work_list, struct drbd_work, list);
2221 list_del_init(&w->list);
2222 update_worker_timing_details(connection, w->cb);
2223 w->cb(w, 1);
2224 } else
2225 dequeue_work_batch(&connection->sender_work, &work_list);
2226 } while (!list_empty(&work_list) || test_bit(DEVICE_WORK_PENDING, &connection->flags));
2227
2228 rcu_read_lock();
2229 idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
2230 struct drbd_device *device = peer_device->device;
2231 D_ASSERT(device, device->state.disk == D_DISKLESS && device->state.conn == C_STANDALONE);
2232 kref_get(&device->kref);
2233 rcu_read_unlock();
2234 drbd_device_cleanup(device);
2235 kref_put(&device->kref, drbd_destroy_device);
2236 rcu_read_lock();
2237 }
2238 rcu_read_unlock();
2239
2240 return 0;
2241}