From: NeilBrown <neilb@suse.de>
Date: Wed, 1 Jul 2009 03:15:35 +0000 (+1000)
Subject: md/raid5: suspend shouldn't affect read requests.
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a5c308d4d1659b1f4833b863394e3e24cdbdfc6e;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git

md/raid5: suspend shouldn't affect read requests.

md allows write to regions on an array to be suspended temporarily.
This allows user-space to participate is aspects of reshape.
In particular, data can be copied with not risk of a race.
We should not be blocking read requests though, so don't.

Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 92ef9b6abfc..1f444ae07f8 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3702,7 +3702,8 @@ static int make_request(struct request_queue *q, struct bio * bi)
 			/* FIXME what if we get a false positive because these
 			 * are being updated.
 			 */
-			if (logical_sector >= mddev->suspend_lo &&
+			if (bio_data_dir(bi) == WRITE &&
+			    logical_sector >= mddev->suspend_lo &&
 			    logical_sector < mddev->suspend_hi) {
 				release_stripe(sh);
 				schedule();