md/raid5: Ensure a batch member is not handled prematurely.

If a stripe is a member of a batch, but not the head, it must
not be handled separately from the rest of the batch.

'clear_batch_ready()' handles this requirement to some
extent but not completely.  If a member is passed to handle_stripe()
a second time it returns '0' indicating the stripe can be handled,
which is wrong.
So add an extra test.

Signed-off-by: NeilBrown <neilb@suse.de>
This commit is contained in:
NeilBrown 2015-05-22 15:20:04 +10:00
parent d0852df543
commit b15a9dbdbf

View File

@ -4200,9 +4200,13 @@ static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s)
static int clear_batch_ready(struct stripe_head *sh)
{
/* Return '1' if this is a member of batch, or
* '0' if it is a lone stripe or a head which can now be
* handled.
*/
struct stripe_head *tmp;
if (!test_and_clear_bit(STRIPE_BATCH_READY, &sh->state))
return 0;
return (sh->batch_head && sh->batch_head != sh);
spin_lock(&sh->stripe_lock);
if (!sh->batch_head) {
spin_unlock(&sh->stripe_lock);