From: Miao Xie <miaox@cn.fujitsu.com>
Date: Thu, 1 Nov 2012 07:34:54 +0000 (+0000)
Subject: Btrfs: fix unprotected extent map operation when logging file extents
X-Git-Tag: v3.8-rc7~6^2~98
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=bbe1426764e5dfaa57e7b12cc954acdb3fb7f94b;p=platform%2Fupstream%2Fkernel-adaptation-pc.git

Btrfs: fix unprotected extent map operation when logging file extents

We forget to protect the modified_extents list, fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
---

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index bcf0e48..d1947af 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -3526,8 +3526,10 @@ next_slot:
 		struct extent_map_tree *tree = &BTRFS_I(inode)->extent_tree;
 		struct extent_map *em, *n;
 
+		write_lock(&tree->lock);
 		list_for_each_entry_safe(em, n, &tree->modified_extents, list)
 			list_del_init(&em->list);
+		write_unlock(&tree->lock);
 	}
 
 	if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) {