From 415e72d034c50520ddb7ff79e7d1792c1306f0c9 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Thu, 17 Jun 2010 17:25:21 +1000 Subject: [PATCH] md/raid5: Allow recovered part of partially recovered devices to be in-sync During a recovery of reshape the early part of some devices might be in-sync while the later parts are not. We we know we are looking at an early part it is good to treat that part as in-sync for stripe calculations. This is particularly important for a reshape which suffers device failure. Treating the data as in-sync can mean the difference between data-safety and data-loss. Signed-off-by: NeilBrown --- drivers/md/raid5.c | 42 ++++++++++++++++++++++++++++++------------ 1 file changed, 30 insertions(+), 12 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index d4b233c25f2e..09f07dadf404 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -3031,7 +3031,6 @@ static void handle_stripe5(struct stripe_head *sh) mdk_rdev_t *rdev; dev = &sh->dev[i]; - clear_bit(R5_Insync, &dev->flags); pr_debug("check %d: state 0x%lx toread %p read %p write %p " "written %p\n", i, dev->flags, dev->toread, dev->read, @@ -3068,17 +3067,27 @@ static void handle_stripe5(struct stripe_head *sh) blocked_rdev = rdev; atomic_inc(&rdev->nr_pending); } - if (!rdev || !test_bit(In_sync, &rdev->flags)) { + clear_bit(R5_Insync, &dev->flags); + if (!rdev) + /* Not in-sync */; + else if (test_bit(In_sync, &rdev->flags)) + set_bit(R5_Insync, &dev->flags); + else { + /* could be in-sync depending on recovery/reshape status */ + if (sh->sector + STRIPE_SECTORS <= rdev->recovery_offset) + set_bit(R5_Insync, &dev->flags); + } + if (!test_bit(R5_Insync, &dev->flags)) { /* The ReadError flag will just be confusing now */ clear_bit(R5_ReadError, &dev->flags); clear_bit(R5_ReWrite, &dev->flags); } - if (!rdev || !test_bit(In_sync, &rdev->flags) - || test_bit(R5_ReadError, &dev->flags)) { + if (test_bit(R5_ReadError, &dev->flags)) + clear_bit(R5_Insync, &dev->flags); + if (!test_bit(R5_Insync, &dev->flags)) { s.failed++; s.failed_num = i; - } else - set_bit(R5_Insync, &dev->flags); + } } rcu_read_unlock(); @@ -3312,7 +3321,6 @@ static void handle_stripe6(struct stripe_head *sh) for (i=disks; i--; ) { mdk_rdev_t *rdev; dev = &sh->dev[i]; - clear_bit(R5_Insync, &dev->flags); pr_debug("check %d: state 0x%lx read %p write %p written %p\n", i, dev->flags, dev->toread, dev->towrite, dev->written); @@ -3350,18 +3358,28 @@ static void handle_stripe6(struct stripe_head *sh) blocked_rdev = rdev; atomic_inc(&rdev->nr_pending); } - if (!rdev || !test_bit(In_sync, &rdev->flags)) { + clear_bit(R5_Insync, &dev->flags); + if (!rdev) + /* Not in-sync */; + else if (test_bit(In_sync, &rdev->flags)) + set_bit(R5_Insync, &dev->flags); + else { + /* in sync if before recovery_offset */ + if (sh->sector + STRIPE_SECTORS <= rdev->recovery_offset) + set_bit(R5_Insync, &dev->flags); + } + if (!test_bit(R5_Insync, &dev->flags)) { /* The ReadError flag will just be confusing now */ clear_bit(R5_ReadError, &dev->flags); clear_bit(R5_ReWrite, &dev->flags); } - if (!rdev || !test_bit(In_sync, &rdev->flags) - || test_bit(R5_ReadError, &dev->flags)) { + if (test_bit(R5_ReadError, &dev->flags)) + clear_bit(R5_Insync, &dev->flags); + if (!test_bit(R5_Insync, &dev->flags)) { if (s.failed < 2) r6s.failed_num[s.failed] = i; s.failed++; - } else - set_bit(R5_Insync, &dev->flags); + } } rcu_read_unlock(); -- 2.34.1