ext4: Automatically allocate delay allocated blocks on close

(cherry picked from commit 7d8f9f7d150dded7b68e61ca6403a1f166fb4edf)

When closing a file that had been previously truncated, force any
delay allocated blocks that to be allocated so that if the filesystem
is mounted with data=ordered, the data blocks will be pushed out to
disk along with the journal commit.  Many application programs expect
this, so we do this to avoid zero length files if the system crashes
unexpectedly.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index cfb2ee1fcc49962998ae939d6c4cb32aefa3fd96..19857211f977f41e17f3182b23dc27a7861ceac1 100644 (file)
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -279,6 +279,7 @@ static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 #define EXT4_STATE_NEW                 0x00000002 /* inode is newly created */
 #define EXT4_STATE_XATTR               0x00000004 /* has in-inode xattrs */
 #define EXT4_STATE_NO_EXPAND           0x00000008 /* No space for expansion */
+#define EXT4_STATE_DA_ALLOC_CLOSE      0x00000010 /* Alloc DA blks on close */
 
 /* Used to pass group descriptor data when online resize is done */
 struct ext4_new_group_input {

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 430eb7978db4c92f0503b92895a59000d8f97b3e..b080072bc507e66622be73750f34b9a280aae4b6 100644 (file)
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -33,6 +33,10 @@
  */
 static int ext4_release_file (struct inode * inode, struct file * filp)
 {
+       if (EXT4_I(inode)->i_state & EXT4_STATE_DA_ALLOC_CLOSE) {
+               ext4_alloc_da_blocks(inode);
+               EXT4_I(inode)->i_state &= ~EXT4_STATE_DA_ALLOC_CLOSE;
+       }
        /* if we are the last writer on the inode, drop the block reservation */
        if ((filp->f_mode & FMODE_WRITE) &&
                        (atomic_read(&inode->i_writecount) == 1))

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index a6e004f8042cb778d33a430c590fdc511210d16e..89eb1dc24d7a403f66ca5d0e63d4f15b4c13a3a9 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3636,6 +3636,9 @@ void ext4_truncate(struct inode *inode)
        if (!ext4_can_truncate(inode))
                return;
 
+       if (inode->i_size == 0)
+               ei->i_state |= EXT4_STATE_DA_ALLOC_CLOSE;
+
        if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
                ext4_ext_truncate(inode);
                return;