3.16.35-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Jes Sorensen <[email protected]> commit e7597e69dec59b65c5525db1626b9d34afdfa678 upstream. 'max_discard_sectors' is in sectors, while 'stripe' is in bytes. This fixes the problem where DISCARD would get disabled on some larger RAID5 configurations (6 or more drives in my testing), while it worked as expected with smaller configurations. Fixes: 620125f2bf8 ("MD: raid5 trim support") Signed-off-by: Jes Sorensen <[email protected]> Signed-off-by: Shaohua Li <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- drivers/md/raid5.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -6264,8 +6264,8 @@ static int run(struct mddev *mddev) } if (discard_supported && - mddev->queue->limits.max_discard_sectors >= stripe && - mddev->queue->limits.discard_granularity >= stripe) + mddev->queue->limits.max_discard_sectors >= (stripe >> 9) && + mddev->queue->limits.discard_granularity >= stripe) queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); else

