From: Joe Thornber <ejt@redhat.com>
Date: Thu, 5 Dec 2013 00:16:11 +0000 (-0500)
Subject: dm thin: return error from alloc_data_block if pool is not in write mode
X-Git-Tag: firefly_0821_release~176^2~4606^2~27
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=8d30abff758b5f6c71343b7da6bb5de129a76c08;p=firefly-linux-kernel-4.4.55.git

dm thin: return error from alloc_data_block if pool is not in write mode

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 5f1b11e45702..1988019df5c9 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -923,6 +923,9 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result)
 	if (pool->no_free_space)
 		return -ENOSPC;
 
+	if (get_pool_mode(pool) != PM_WRITE)
+		return -EINVAL;
+
 	r = dm_pool_get_free_block_count(pool->pmd, &free_blocks);
 	if (r)
 		return r;