md: raid5: fix clearing of biofill operations

ops_complete_biofill() runs outside of spin_lock(&sh->lock) and clears the
'pending' and 'ack' bits.  Since the test_and_ack_op() macro only checks
against 'complete' it can get an inconsistent snapshot of pending work.

Move the clearing of these bits to handle_stripe5(), under the lock.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Joel Bertrand <joel.bertrand@systella.fr>
Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Stable <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Dan Williams 2007-10-22 20:45:11 -07:00 committed by Linus Torvalds
parent 85bfb4da8c
commit 4ae3f847e4

View File

@ -376,7 +376,12 @@ static unsigned long get_stripe_work(struct stripe_head *sh)
ack++;
sh->ops.count -= ack;
BUG_ON(sh->ops.count < 0);
if (unlikely(sh->ops.count < 0)) {
printk(KERN_ERR "pending: %#lx ops.pending: %#lx ops.ack: %#lx "
"ops.complete: %#lx\n", pending, sh->ops.pending,
sh->ops.ack, sh->ops.complete);
BUG();
}
return pending;
}
@ -550,8 +555,7 @@ static void ops_complete_biofill(void *stripe_head_ref)
}
}
}
clear_bit(STRIPE_OP_BIOFILL, &sh->ops.ack);
clear_bit(STRIPE_OP_BIOFILL, &sh->ops.pending);
set_bit(STRIPE_OP_BIOFILL, &sh->ops.complete);
return_io(return_bi);
@ -2893,6 +2897,13 @@ static void handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state);
/* Now to look around and see what can be done */
/* clean-up completed biofill operations */
if (test_bit(STRIPE_OP_BIOFILL, &sh->ops.complete)) {
clear_bit(STRIPE_OP_BIOFILL, &sh->ops.pending);
clear_bit(STRIPE_OP_BIOFILL, &sh->ops.ack);
clear_bit(STRIPE_OP_BIOFILL, &sh->ops.complete);
}
rcu_read_lock();
for (i=disks; i--; ) {
mdk_rdev_t *rdev;