2008-03-04 12:40:51

by Aneesh Kumar K.V

Subject: [PATCH] ext4: Fix fallocate error path.

Put the old extent details back if we fail to split the
uninitialized extent.

Signed-off-by: Aneesh Kumar K.V <[email protected]>
---
fs/ext4/extents.c | 26 ++++++++++++++++++++++++--
1 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 39d5315..d315cc1 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -2152,7 +2152,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
ext4_lblk_t iblock,
unsigned long max_blocks)
{
- struct ext4_extent *ex, newex;
+ struct ext4_extent *ex, newex, orig_ex;
struct ext4_extent *ex1 = NULL;
struct ext4_extent *ex2 = NULL;
struct ext4_extent *ex3 = NULL;
@@ -2171,6 +2171,9 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
allocated = ee_len - (iblock - ee_block);
newblock = iblock - ee_block + ext_pblock(ex);
ex2 = ex;
+ orig_ex.ee_block = ex->ee_block;
+ orig_ex.ee_len = cpu_to_le16(ee_len);
+ ext4_ext_store_pblock(&orig_ex, ext_pblock(ex));

err = ext4_ext_get_access(handle, inode, path + depth);
if (err)
@@ -2199,13 +2202,25 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
ex3->ee_len = cpu_to_le16(allocated - max_blocks);
ext4_ext_mark_uninitialized(ex3);
err = ext4_ext_insert_extent(handle, inode, path, ex3);
- if (err)
+ if (err) {
+ ex->ee_block = orig_ex.ee_block;
+ ex->ee_len = orig_ex.ee_len;
+ ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+ ext4_ext_mark_uninitialized(ex);
+ ext4_ext_dirty(handle, inode, path + depth);
goto out;
+ }
/*
* The depth, and hence eh & ex might change
* as part of the insert above.
*/
newdepth = ext_depth(inode);
+ /*
+ * update the extent length after successfull insert of the
+ * split extent
+ */
+ orig_ex.ee_len = cpu_to_le16(ee_len -
+ ext4_ext_get_actual_len(ex3));
if (newdepth != depth) {
depth = newdepth;
ext4_ext_drop_refs(path);
@@ -2280,6 +2295,13 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
goto out;
insert:
err = ext4_ext_insert_extent(handle, inode, path, &newex);
+ if (err) {
+ ex->ee_block = orig_ex.ee_block;
+ ex->ee_len = orig_ex.ee_len;
+ ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+ ext4_ext_mark_uninitialized(ex);
+ ext4_ext_dirty(handle, inode, path + depth);
+ }
out:
return err ? err : allocated;
}
--
1.5.4.3.422.g34cd6.dirty

2008-03-05 00:45:10

by Mingming Cao

Subject: Re: [PATCH] ext4: Fix fallocate error path.

On Tue, 2008-03-04 at 18:10 +0530, Aneesh Kumar K.V wrote:
> Put the old extent details back if we fail to split the
> uninitialized extent.
>
Reviewed, add to the patch queue.

Mingming
> Signed-off-by: Aneesh Kumar K.V <[email protected]>
> ---
> fs/ext4/extents.c | 26 ++++++++++++++++++++++++--
> 1 files changed, 24 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
> index 39d5315..d315cc1 100644
> --- a/fs/ext4/extents.c
> +++ b/fs/ext4/extents.c
> @@ -2152,7 +2152,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
> ext4_lblk_t iblock,
> unsigned long max_blocks)
> {
> - struct ext4_extent *ex, newex;
> + struct ext4_extent *ex, newex, orig_ex;
> struct ext4_extent *ex1 = NULL;
> struct ext4_extent *ex2 = NULL;
> struct ext4_extent *ex3 = NULL;
> @@ -2171,6 +2171,9 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
> allocated = ee_len - (iblock - ee_block);
> newblock = iblock - ee_block + ext_pblock(ex);
> ex2 = ex;
> + orig_ex.ee_block = ex->ee_block;
> + orig_ex.ee_len = cpu_to_le16(ee_len);
> + ext4_ext_store_pblock(&orig_ex, ext_pblock(ex));
>
> err = ext4_ext_get_access(handle, inode, path + depth);
> if (err)
> @@ -2199,13 +2202,25 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
> ex3->ee_len = cpu_to_le16(allocated - max_blocks);
> ext4_ext_mark_uninitialized(ex3);
> err = ext4_ext_insert_extent(handle, inode, path, ex3);
> - if (err)
> + if (err) {
> + ex->ee_block = orig_ex.ee_block;
> + ex->ee_len = orig_ex.ee_len;
> + ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
> + ext4_ext_mark_uninitialized(ex);
> + ext4_ext_dirty(handle, inode, path + depth);
> goto out;
> + }
> /*
> * The depth, and hence eh & ex might change
> * as part of the insert above.
> */
> newdepth = ext_depth(inode);
> + /*
> + * update the extent length after successfull insert of the
> + * split extent
> + */
> + orig_ex.ee_len = cpu_to_le16(ee_len -
> + ext4_ext_get_actual_len(ex3));
> if (newdepth != depth) {
> depth = newdepth;
> ext4_ext_drop_refs(path);
> @@ -2280,6 +2295,13 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
> goto out;
> insert:
> err = ext4_ext_insert_extent(handle, inode, path, &newex);
> + if (err) {
> + ex->ee_block = orig_ex.ee_block;
> + ex->ee_len = orig_ex.ee_len;
> + ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
> + ext4_ext_mark_uninitialized(ex);
> + ext4_ext_dirty(handle, inode, path + depth);
> + }
> out:
> return err ? err : allocated;
> }