From ca64cae96037de16e4af92678814f5d4bf0c1c65 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 21 Nov 2012 16:33:40 +1100 Subject: [PATCH] md/raid5: Make sure we clear R5_Discard when discard is finished. commit 9e44476851e91c86c98eb92b9bc27fb801f89072 MD: raid5 avoid unnecessary zero page for trim change raid5 to clear R5_Discard when the complete request is handled rather than when submitting the per-device discard request. However it did not clear R5_Discard for the parity device. This means that if the stripe_head was reused before it expired from the cache, the setting would be wrong and a hang would result. Also if the R5_Uptodate bit happens to be set, R5_Discard again won't be cleared. But R5_Uptodate really should be clear at this point. So make sure R5_Discard is cleared in all cases, and clear R5_Uptodate when a 'discard' completes. Signed-off-by: NeilBrown --- drivers/md/raid5.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 0fb988556eea..a4502686e7a8 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2774,10 +2774,12 @@ static void handle_stripe_clean_event(struct r5conf *conf, dev = &sh->dev[i]; if (!test_bit(R5_LOCKED, &dev->flags) && (test_bit(R5_UPTODATE, &dev->flags) || - test_and_clear_bit(R5_Discard, &dev->flags))) { + test_bit(R5_Discard, &dev->flags))) { /* We can return any write requests */ struct bio *wbi, *wbi2; pr_debug("Return write for disc %d\n", i); + if (test_and_clear_bit(R5_Discard, &dev->flags)) + clear_bit(R5_UPTODATE, &dev->flags); wbi = dev->written; dev->written = NULL; while (wbi && wbi->bi_sector < @@ -2795,7 +2797,8 @@ static void handle_stripe_clean_event(struct r5conf *conf, !test_bit(STRIPE_DEGRADED, &sh->state), 0); } - } + } else if (test_bit(R5_Discard, &sh->dev[i].flags)) + clear_bit(R5_Discard, &sh->dev[i].flags); if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) if (atomic_dec_and_test(&conf->pending_full_writes)) -- 2.30.2