Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'md/4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md
Pull MD fixes from Shaohua Li:
"A few fixes for MD. Mainly fix a problem introduced in 4.13, which we
retry bio for some code paths but not all in some situations"
* tag 'md/4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
md/raid5: cap worker count
dm-raid: fix a race condition in request handling
md: fix a race condition for flush request handling
md: separate request handling
+50
-32
+1
-1
drivers/md/dm-raid.c
+1
-1
drivers/md/dm-raid.c
+43
-29
drivers/md/md.c
+43
-29
drivers/md/md.c
···
266
266
* call has finished, the bio has been linked into some internal structure
267
267
* and so is visible to ->quiesce(), so we don't need the refcount any more.
268
268
*/
269
+
void md_handle_request(struct mddev *mddev, struct bio *bio)
270
+
{
271
+
check_suspended:
272
+
rcu_read_lock();
273
+
if (mddev->suspended) {
274
+
DEFINE_WAIT(__wait);
275
+
for (;;) {
276
+
prepare_to_wait(&mddev->sb_wait, &__wait,
277
+
TASK_UNINTERRUPTIBLE);
278
+
if (!mddev->suspended)
279
+
break;
280
+
rcu_read_unlock();
281
+
schedule();
282
+
rcu_read_lock();
283
+
}
284
+
finish_wait(&mddev->sb_wait, &__wait);
285
+
}
286
+
atomic_inc(&mddev->active_io);
287
+
rcu_read_unlock();
288
+
289
+
if (!mddev->pers->make_request(mddev, bio)) {
290
+
atomic_dec(&mddev->active_io);
291
+
wake_up(&mddev->sb_wait);
292
+
goto check_suspended;
293
+
}
294
+
295
+
if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
296
+
wake_up(&mddev->sb_wait);
297
+
}
298
+
EXPORT_SYMBOL(md_handle_request);
299
+
269
300
static blk_qc_t md_make_request(struct request_queue *q, struct bio *bio)
270
301
{
271
302
const int rw = bio_data_dir(bio);
···
316
285
bio_endio(bio);
317
286
return BLK_QC_T_NONE;
318
287
}
319
-
check_suspended:
320
-
rcu_read_lock();
321
-
if (mddev->suspended) {
322
-
DEFINE_WAIT(__wait);
323
-
for (;;) {
324
-
prepare_to_wait(&mddev->sb_wait, &__wait,
325
-
TASK_UNINTERRUPTIBLE);
326
-
if (!mddev->suspended)
327
-
break;
328
-
rcu_read_unlock();
329
-
schedule();
330
-
rcu_read_lock();
331
-
}
332
-
finish_wait(&mddev->sb_wait, &__wait);
333
-
}
334
-
atomic_inc(&mddev->active_io);
335
-
rcu_read_unlock();
336
288
337
289
/*
338
290
* save the sectors now since our bio can
···
324
310
sectors = bio_sectors(bio);
325
311
/* bio could be mergeable after passing to underlayer */
326
312
bio->bi_opf &= ~REQ_NOMERGE;
327
-
if (!mddev->pers->make_request(mddev, bio)) {
328
-
atomic_dec(&mddev->active_io);
329
-
wake_up(&mddev->sb_wait);
330
-
goto check_suspended;
331
-
}
313
+
314
+
md_handle_request(mddev, bio);
332
315
333
316
cpu = part_stat_lock();
334
317
part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]);
335
318
part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], sectors);
336
319
part_stat_unlock();
337
-
338
-
if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
339
-
wake_up(&mddev->sb_wait);
340
320
341
321
return BLK_QC_T_NONE;
342
322
}
···
447
439
struct mddev *mddev = container_of(ws, struct mddev, flush_work);
448
440
struct bio *bio = mddev->flush_bio;
449
441
442
+
/*
443
+
* must reset flush_bio before calling into md_handle_request to avoid a
444
+
* deadlock, because other bios passed md_handle_request suspend check
445
+
* could wait for this and below md_handle_request could wait for those
446
+
* bios because of suspend check
447
+
*/
448
+
mddev->flush_bio = NULL;
449
+
wake_up(&mddev->sb_wait);
450
+
450
451
if (bio->bi_iter.bi_size == 0)
451
452
/* an empty barrier - all done */
452
453
bio_endio(bio);
453
454
else {
454
455
bio->bi_opf &= ~REQ_PREFLUSH;
455
-
mddev->pers->make_request(mddev, bio);
456
+
md_handle_request(mddev, bio);
456
457
}
457
-
458
-
mddev->flush_bio = NULL;
459
-
wake_up(&mddev->sb_wait);
460
458
}
461
459
462
460
void md_flush_request(struct mddev *mddev, struct bio *bio)
+1
drivers/md/md.h
+1
drivers/md/md.h
···
692
692
extern int md_rdev_init(struct md_rdev *rdev);
693
693
extern void md_rdev_clear(struct md_rdev *rdev);
694
694
695
+
extern void md_handle_request(struct mddev *mddev, struct bio *bio);
695
696
extern void mddev_suspend(struct mddev *mddev);
696
697
extern void mddev_resume(struct mddev *mddev);
697
698
extern struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs,
+5
-2
drivers/md/raid5.c
+5
-2
drivers/md/raid5.c
···
6575
6575
raid5_store_group_thread_cnt(struct mddev *mddev, const char *page, size_t len)
6576
6576
{
6577
6577
struct r5conf *conf;
6578
-
unsigned long new;
6578
+
unsigned int new;
6579
6579
int err;
6580
6580
struct r5worker_group *new_groups, *old_groups;
6581
6581
int group_cnt, worker_cnt_per_group;
6582
6582
6583
6583
if (len >= PAGE_SIZE)
6584
6584
return -EINVAL;
6585
-
if (kstrtoul(page, 10, &new))
6585
+
if (kstrtouint(page, 10, &new))
6586
+
return -EINVAL;
6587
+
/* 8192 should be big enough */
6588
+
if (new > 8192)
6586
6589
return -EINVAL;
6587
6590
6588
6591
err = mddev_lock(mddev);