From 4e2c6567efdd6f252e1874c41c8db4abfb0a9bf3 Mon Sep 17 00:00:00 2001 From: Song Liu Date: Wed, 9 Dec 2020 11:43:43 -0800 Subject: Revert "md/raid10: pull codes that wait for blocked dev into one function" This reverts commit f046f5d0d79cdb968f219ce249e497fd1accf484. Matthew Ruffell reported data corruption in raid10 due to the changes in discard handling [1]. Revert these changes before we find a proper fix. [1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1907262/ Cc: Matthew Ruffell Cc: Xiao Ni Signed-off-by: Song Liu --- drivers/md/raid10.c | 118 +++++++++++++++++++++++----------------------------- 1 file changed, 51 insertions(+), 67 deletions(-) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 4ad8447fa868..f2ec44fda1a0 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1275,75 +1275,12 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio, } } -static void wait_blocked_dev(struct mddev *mddev, struct r10bio *r10_bio) -{ - int i; - struct r10conf *conf = mddev->private; - struct md_rdev *blocked_rdev; - -retry_wait: - blocked_rdev = NULL; - rcu_read_lock(); - for (i = 0; i < conf->copies; i++) { - struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); - struct md_rdev *rrdev = rcu_dereference( - conf->mirrors[i].replacement); - if (rdev == rrdev) - rrdev = NULL; - if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { - atomic_inc(&rdev->nr_pending); - blocked_rdev = rdev; - break; - } - if (rrdev && unlikely(test_bit(Blocked, &rrdev->flags))) { - atomic_inc(&rrdev->nr_pending); - blocked_rdev = rrdev; - break; - } - - if (rdev && test_bit(WriteErrorSeen, &rdev->flags)) { - sector_t first_bad; - sector_t dev_sector = r10_bio->devs[i].addr; - int bad_sectors; - int is_bad; - - /* Discard request doesn't care the write result - * so it doesn't need to wait blocked disk here. - */ - if (!r10_bio->sectors) - continue; - - is_bad = is_badblock(rdev, dev_sector, r10_bio->sectors, - &first_bad, &bad_sectors); - if (is_bad < 0) { - /* Mustn't write here until the bad block - * is acknowledged - */ - atomic_inc(&rdev->nr_pending); - set_bit(BlockedBadBlocks, &rdev->flags); - blocked_rdev = rdev; - break; - } - } - } - rcu_read_unlock(); - - if (unlikely(blocked_rdev)) { - /* Have to wait for this device to get unblocked, then retry */ - allow_barrier(conf); - raid10_log(conf->mddev, "%s wait rdev %d blocked", - __func__, blocked_rdev->raid_disk); - md_wait_for_blocked_rdev(blocked_rdev, mddev); - wait_barrier(conf); - goto retry_wait; - } -} - static void raid10_write_request(struct mddev *mddev, struct bio *bio, struct r10bio *r10_bio) { struct r10conf *conf = mddev->private; int i; + struct md_rdev *blocked_rdev; sector_t sectors; int max_sectors; @@ -1401,9 +1338,8 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio, r10_bio->read_slot = -1; /* make sure repl_bio gets freed */ raid10_find_phys(conf, r10_bio); - - wait_blocked_dev(mddev, r10_bio); - +retry_write: + blocked_rdev = NULL; rcu_read_lock(); max_sectors = r10_bio->sectors; @@ -1414,6 +1350,16 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio, conf->mirrors[d].replacement); if (rdev == rrdev) rrdev = NULL; + if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { + atomic_inc(&rdev->nr_pending); + blocked_rdev = rdev; + break; + } + if (rrdev && unlikely(test_bit(Blocked, &rrdev->flags))) { + atomic_inc(&rrdev->nr_pending); + blocked_rdev = rrdev; + break; + } if (rdev && (test_bit(Faulty, &rdev->flags))) rdev = NULL; if (rrdev && (test_bit(Faulty, &rrdev->flags))) @@ -1434,6 +1380,15 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio, is_bad = is_badblock(rdev, dev_sector, max_sectors, &first_bad, &bad_sectors); + if (is_bad < 0) { + /* Mustn't write here until the bad block + * is acknowledged + */ + atomic_inc(&rdev->nr_pending); + set_bit(BlockedBadBlocks, &rdev->flags); + blocked_rdev = rdev; + break; + } if (is_bad && first_bad <= dev_sector) { /* Cannot write here at all */ bad_sectors -= (dev_sector - first_bad); @@ -1469,6 +1424,35 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio, } rcu_read_unlock(); + if (unlikely(blocked_rdev)) { + /* Have to wait for this device to get unblocked, then retry */ + int j; + int d; + + for (j = 0; j < i; j++) { + if (r10_bio->devs[j].bio) { + d = r10_bio->devs[j].devnum; + rdev_dec_pending(conf->mirrors[d].rdev, mddev); + } + if (r10_bio->devs[j].repl_bio) { + struct md_rdev *rdev; + d = r10_bio->devs[j].devnum; + rdev = conf->mirrors[d].replacement; + if (!rdev) { + /* Race with remove_disk */ + smp_mb(); + rdev = conf->mirrors[d].rdev; + } + rdev_dec_pending(rdev, mddev); + } + } + allow_barrier(conf); + raid10_log(conf->mddev, "wait rdev %d blocked", blocked_rdev->raid_disk); + md_wait_for_blocked_rdev(blocked_rdev, mddev); + wait_barrier(conf); + goto retry_write; + } + if (max_sectors < r10_bio->sectors) r10_bio->sectors = max_sectors; -- cgit v1.2.3