ext4: Make ext4_get_blocks_wrap take the truncate_mutex early.

When doing a migrate from ext3 to ext4 inode we need to make sure the test
for inode type and walking inode data happens inside  lock. To make this
happen move truncate_mutex early before checking the i_flags.


This actually should enable us to remove the verify_chain().

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/ext4_fs.h b/include/linux/ext4_fs.h
index 55a376e7bca0..583049c1d366 100644
--- a/include/linux/ext4_fs.h
+++ b/include/linux/ext4_fs.h
@@ -1113,6 +1113,7 @@ ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
                         int create, int extend_disksize)
 {
         int retval;
+        mutex_lock(&EXT4_I(inode)->truncate_mutex);
         if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
                 retval = ext4_ext_get_blocks(handle, inode,
                                                 (ext4_lblk_t)block, max_blocks,
@@ -1122,6 +1123,7 @@ ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
                                                 (ext4_lblk_t)block, max_blocks,
                                                 bh, create, extend_disksize);
         }
+        mutex_unlock(&EXT4_I(inode)->truncate_mutex);
         return retval;
 }