From: Mike Snitzer <snitzer@redhat.com>
Date: Wed, 21 Aug 2013 21:40:11 +0000 (-0400)
Subject: dm thin: set pool read-only if breaking_sharing fails block allocation
X-Git-Tag: v3.12-rc1~70^2~6
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=d6fc204201ca7d019ab0eb5304d1e5c690ddedc8;p=linux.git

dm thin: set pool read-only if breaking_sharing fails block allocation

break_sharing() now handles an arbitrary alloc_data_block() error
the same way as provision_block(): marks pool read-only and errors the
cell.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
---

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index c151cbf80b10..3aff1c27e5b4 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -1086,6 +1086,7 @@ static void break_sharing(struct thin_c *tc, struct bio *bio, dm_block_t block,
 {
 	int r;
 	dm_block_t data_block;
+	struct pool *pool = tc->pool;
 
 	r = alloc_data_block(tc, &data_block);
 	switch (r) {
@@ -1095,13 +1096,14 @@ static void break_sharing(struct thin_c *tc, struct bio *bio, dm_block_t block,
 		break;
 
 	case -ENOSPC:
-		no_space(tc->pool, cell);
+		no_space(pool, cell);
 		break;
 
 	default:
 		DMERR_LIMIT("%s: alloc_data_block() failed: error = %d",
 			    __func__, r);
-		cell_error(tc->pool, cell);
+		set_pool_mode(pool, PM_READ_ONLY);
+		cell_error(pool, cell);
 		break;
 	}
 }