Btrfs: fix wrong disk space information of the files

Btrfsck report errors after the 83th case of xfstests was run, The error
number is 400, it means the used disk space of the file is wrong.

The reason of this bug is that:
The file truncation may fail when the space of the file system is not enough,
and leave some file extents, whose offset are beyond the end of the files.
When we want to expand those files, we will drop those file extents, and
put in dummy file extents, and then we should update the i-node. But btrfs
forgets to do it.

This patch adds the forgotten i-node update.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 4bbceb928aff95488f58a5fd7949341f639138eb..f1c4bceed072b551389057686e2372135e40d221 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3327,7 +3327,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
                        u64 hint_byte = 0;
                        hole_size = last_byte - cur_offset;
 
-                       trans = btrfs_start_transaction(root, 2);
+                       trans = btrfs_start_transaction(root, 3);
                        if (IS_ERR(trans)) {
                                err = PTR_ERR(trans);
                                break;
@@ -3337,6 +3337,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
                                                 cur_offset + hole_size,
                                                 &hint_byte, 1);
                        if (err) {
+                               btrfs_update_inode(trans, root, inode);
                                btrfs_end_transaction(trans, root);
                                break;
                        }
@@ -3346,6 +3347,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
                                        0, hole_size, 0, hole_size,
                                        0, 0, 0);
                        if (err) {
+                               btrfs_update_inode(trans, root, inode);
                                btrfs_end_transaction(trans, root);
                                break;
                        }
@@ -3353,6 +3355,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
                        btrfs_drop_extent_cache(inode, hole_start,
                                        last_byte - 1, 0);
 
+                       btrfs_update_inode(trans, root, inode);
                        btrfs_end_transaction(trans, root);
                }
                free_extent_map(em);