ext4: merge uninitialized extents

Allow for merging uninitialized extents.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Darrick J. Wong 2014-02-20 21:17:35 -05:00 committed by Theodore Ts'o
parent e251f9bca9
commit a9b8241594

View File

@ -1691,7 +1691,7 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
* the extent that was written properly split out and conversion to
* initialized is trivial.
*/
if (ext4_ext_is_uninitialized(ex1) || ext4_ext_is_uninitialized(ex2))
if (ext4_ext_is_uninitialized(ex1) != ext4_ext_is_uninitialized(ex2))
return 0;
ext1_ee_len = ext4_ext_get_actual_len(ex1);
@ -1708,6 +1708,11 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
*/
if (ext1_ee_len + ext2_ee_len > EXT_INIT_MAX_LEN)
return 0;
if (ext4_ext_is_uninitialized(ex1) &&
(ext4_test_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN) ||
atomic_read(&EXT4_I(inode)->i_unwritten) ||
(ext1_ee_len + ext2_ee_len > EXT_UNINIT_MAX_LEN)))
return 0;
#ifdef AGGRESSIVE_TEST
if (ext1_ee_len >= 4)
return 0;
@ -1731,7 +1736,7 @@ static int ext4_ext_try_to_merge_right(struct inode *inode,
{
struct ext4_extent_header *eh;
unsigned int depth, len;
int merge_done = 0;
int merge_done = 0, uninit;
depth = ext_depth(inode);
BUG_ON(path[depth].p_hdr == NULL);
@ -1741,8 +1746,11 @@ static int ext4_ext_try_to_merge_right(struct inode *inode,
if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
break;
/* merge with next extent! */
uninit = ext4_ext_is_uninitialized(ex);
ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
+ ext4_ext_get_actual_len(ex + 1));
if (uninit)
ext4_ext_mark_uninitialized(ex);
if (ex + 1 < EXT_LAST_EXTENT(eh)) {
len = (EXT_LAST_EXTENT(eh) - ex - 1)
@ -1896,7 +1904,7 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
struct ext4_ext_path *npath = NULL;
int depth, len, err;
ext4_lblk_t next;
int mb_flags = 0;
int mb_flags = 0, uninit;
if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
@ -1946,9 +1954,11 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
path + depth);
if (err)
return err;
uninit = ext4_ext_is_uninitialized(ex);
ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
+ ext4_ext_get_actual_len(newext));
if (uninit)
ext4_ext_mark_uninitialized(ex);
eh = path[depth].p_hdr;
nearex = ex;
goto merge;
@ -1971,10 +1981,13 @@ prepend:
if (err)
return err;
uninit = ext4_ext_is_uninitialized(ex);
ex->ee_block = newext->ee_block;
ext4_ext_store_pblock(ex, ext4_ext_pblock(newext));
ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
+ ext4_ext_get_actual_len(newext));
if (uninit)
ext4_ext_mark_uninitialized(ex);
eh = path[depth].p_hdr;
nearex = ex;
goto merge;