From: Yan Zheng <zheng.yan@oracle.com>
Date: Tue, 28 Jul 2009 12:41:57 +0000 (-0400)
Subject: Btrfs: Fix async caching interaction with unmount
X-Git-Tag: v2.6.31-rc5~7^2~2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f25784b35f590c81d5fb8245a8cd45e1afb6f1b2;p=platform%2Fkernel%2Flinux-3.10.git

Btrfs: Fix async caching interaction with unmount

- don't stop the caching thread until btrfs_commit_super return.

- if caching is interrupted by umount, set last to (u64)-1.
  otherwise the un-scanned range of block group will be considered
  as free extent.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
---

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index c658397..3a9b887 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2317,6 +2317,9 @@ int close_ctree(struct btrfs_root *root)
 			printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
 	}
 
+	fs_info->closing = 2;
+	smp_mb();
+
 	if (fs_info->delalloc_bytes) {
 		printk(KERN_INFO "btrfs: at unmount delalloc count %llu\n",
 		       (unsigned long long)fs_info->delalloc_bytes);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 08188f1..fadf69a 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -288,8 +288,10 @@ again:
 
 	while (1) {
 		smp_mb();
-		if (block_group->fs_info->closing)
+		if (block_group->fs_info->closing > 1) {
+			last = (u64)-1;
 			break;
+		}
 
 		leaf = path->nodes[0];
 		slot = path->slots[0];