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 <neilb@suse.de>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index d4b233c..09f07da 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3031,7 +3031,6 @@
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 @@
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 @@
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 @@
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();