[PATCH] ext4: Update i_disksize correctly in ext4_get_block

[PATCH] ext4: Update i_disksize correctly in ext4_get_block

[Aneesh Kumar K.V]

With delayed allocation we delay the allocation of blocks
and request for blocks in multiple chunks. We should not
update i_disksize to inode.i_size unless we are allocating
blocks corresponding to the end of file.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
 fs/ext4/extents.c |   10 ++++++++--
 fs/ext4/inode.c   |   10 ++++++++--
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index dae3b60..a6d7165 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -2698,6 +2698,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 	int err = 0, depth, ret;
 	unsigned long allocated = 0;
 	struct ext4_allocation_request ar;
+	loff_t disksize;
 
 	__clear_bit(BH_New, &bh_result->b_state);
 	ext_debug("blocks %u/%lu requested for inode %u\n",
@@ -2885,8 +2886,13 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 		goto out2;
 	}
 
-	if (extend_disksize && inode->i_size > EXT4_I(inode)->i_disksize)
-		EXT4_I(inode)->i_disksize = inode->i_size;
+	if (extend_disksize) {
+		disksize = ((loff_t) newblock + ar.len) << inode->i_blkbits;
+		if (disksize > i_size_read(inode))
+			disksize = i_size_read(inode);
+		if (disksize > EXT4_I(inode)->i_disksize)
+			EXT4_I(inode)->i_disksize = disksize;
+	}
 
 	/* previous routine could use block we allocated */
 	newblock = ext_pblock(&newex);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index a51d5f4..5265933 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -846,6 +846,7 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
 	struct ext4_inode_info *ei = EXT4_I(inode);
 	int count = 0;
 	ext4_fsblk_t first_block = 0;
+	loff_t disksize;
 
 
 	J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL));
@@ -921,8 +922,13 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
 	 * protect it if you're about to implement concurrent
 	 * ext4_get_block() -bzzz
 	*/
-	if (!err && extend_disksize && inode->i_size > ei->i_disksize)
-		ei->i_disksize = inode->i_size;
+	if (!err && extend_disksize) {
+		disksize = ((loff_t) iblock + count) << inode->i_blkbits;
+		if (disksize > i_size_read(inode))
+			disksize = i_size_read(inode);
+		if (disksize > ei->i_disksize)
+			ei->i_disksize = disksize;
+	}
 	if (err)
 		goto cleanup;
 
-- 
1.5.6.rc2.15.g457bb.dirty

Re: [PATCH] ext4: Update i_disksize correctly in ext4_get_block

[Aneesh Kumar K.V]

On Mon, Jun 09, 2008 at 01:39:30PM +0530, Aneesh Kumar K.V wrote:
> With delayed allocation we delay the allocation of blocks
> and request for blocks in multiple chunks. We should not
> update i_disksize to inode.i_size unless we are allocating
> blocks corresponding to the end of file.
> 
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> ---
>  fs/ext4/extents.c |   10 ++++++++--
>  fs/ext4/inode.c   |   10 ++++++++--
>  2 files changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
> index dae3b60..a6d7165 100644
> --- a/fs/ext4/extents.c
> +++ b/fs/ext4/extents.c
> @@ -2698,6 +2698,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
>  	int err = 0, depth, ret;
>  	unsigned long allocated = 0;
>  	struct ext4_allocation_request ar;
> +	loff_t disksize;
> 
>  	__clear_bit(BH_New, &bh_result->b_state);
>  	ext_debug("blocks %u/%lu requested for inode %u\n",
> @@ -2885,8 +2886,13 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
>  		goto out2;
>  	}
> 
> -	if (extend_disksize && inode->i_size > EXT4_I(inode)->i_disksize)
> -		EXT4_I(inode)->i_disksize = inode->i_size;
> +	if (extend_disksize) {
> +		disksize = ((loff_t) newblock + ar.len) << inode->i_blkbits;


s/newblock/iblock

I will send a new patch.



-aneesh