From affa9d28f7e9a802c8f497ed54fe79a5689d95e9 Mon Sep 17 00:00:00 2001 From: Heinz Mauelshagen Date: Thu, 24 Nov 2016 18:53:44 +0100 Subject: dm raid: don't allow "write behind" with raid4/5/6 Remove CTR_FLAG_MAX_WRITE_BEHIND from raid4/5/6's valid ctr flags. Only the md raid1 personality supports setting a maximum number of "write behind" write IOs on any legs set to "write mostly". "write mostly" enhances throughput with slow links/disks. Technically the "write behind" value is a write intent bitmap property only being respected by the raid1 personality. It allows a maximum number of "write behind" writes to any "write mostly" raid1 mirror legs to be delayed and avoids reads from such legs. No other MD personalities supported via dm-raid make use of "write behind", thus setting this property is superfluous; it wouldn't cause harm but it is correct to reject it. Signed-off-by: Heinz Mauelshagen Signed-off-by: Mike Snitzer --- drivers/md/dm-raid.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'drivers/md') diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 698b03e9d955..9d5c6bb9e35b 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -160,7 +160,6 @@ struct raid_dev { CTR_FLAG_DAEMON_SLEEP | \ CTR_FLAG_MIN_RECOVERY_RATE | \ CTR_FLAG_MAX_RECOVERY_RATE | \ - CTR_FLAG_MAX_WRITE_BEHIND | \ CTR_FLAG_STRIPE_CACHE | \ CTR_FLAG_REGION_SIZE | \ CTR_FLAG_DELTA_DISKS | \ @@ -171,7 +170,6 @@ struct raid_dev { CTR_FLAG_DAEMON_SLEEP | \ CTR_FLAG_MIN_RECOVERY_RATE | \ CTR_FLAG_MAX_RECOVERY_RATE | \ - CTR_FLAG_MAX_WRITE_BEHIND | \ CTR_FLAG_STRIPE_CACHE | \ CTR_FLAG_REGION_SIZE | \ CTR_FLAG_DELTA_DISKS | \ -- cgit v1.2.3