[PATCH 3/4 v2] code clean up for dio fallocate handling

[PATCH 3/4 v2] code clean up for dio fallocate handling

[Mingming]

ext4: code clean up for dio fallocate handling

The ext4_debug() call in ext4_end_io_dio() (inode.c) has a
should be moved after checking the io_end structure to be not a NULL pointer.

The comment above ext4_get_block_dio_write() ("Maximum
number of blocks...") is a duplicate; the original and correct comment
is above the #define DIO_MAX_BLOCKS up above.

The check for allocated > max_blocks in ext4_split_unwritten_extents()
can be removed, since the code returns immediately once allocated blocks is
less or equals to the requested blocks to convert.

Based on review comments from Curt Wohlgemuth.

Signed-off-by:	Mingming Cao <cmm@us.ibm.com>
---
 fs/ext4/extents.c |   96 +++++++++++++++++++++++++-----------------------------
 fs/ext4/inode.c   |    9 ++---
 2 files changed, 50 insertions(+), 55 deletions(-)

Index: linux-2.6.31-rc4/fs/ext4/inode.c
===================================================================
--- linux-2.6.31-rc4.orig/fs/ext4/inode.c
+++ linux-2.6.31-rc4/fs/ext4/inode.c
@@ -3367,8 +3367,6 @@ out:
 	return ret;
 }
 
-/* Maximum number of blocks we map for direct IO at once. */

Re: [PATCH 3/4 v2] code clean up for dio fallocate handling

[Theodore Tso]

On Thu, Oct 08, 2009 at 06:13:33PM -0700, Mingming wrote:
> ext4: code clean up for dio fallocate handling
> 
> The ext4_debug() call in ext4_end_io_dio() (inode.c) has a
> should be moved after checking the io_end structure to be not a NULL pointer.
> 
> The comment above ext4_get_block_dio_write() ("Maximum
> number of blocks...") is a duplicate; the original and correct comment
> is above the #define DIO_MAX_BLOCKS up above.
> 
> The check for allocated > max_blocks in ext4_split_unwritten_extents()
> can be removed, since the code returns immediately once allocated blocks is
> less or equals to the requested blocks to convert.
> 
> Based on review comments from Curt Wohlgemuth.
> 
> Signed-off-by:	Mingming Cao <cmm@us.ibm.com>

The changes described last paragraph wasn't in the patch.  I assume it
was because patch #4 in this series changed:

	if (allocated <= max_blocks)

to:

	if (iblock == ee_block && allocated <= max_blocks)

I replaced the commit description with the following:


ext4: code clean up for dio fallocate handling

From: Mingming <cmm@us.ibm.com>

The ext4_debug() call in ext4_end_io_dio() should be moved after the
check to make sure that io_end is non-NULL.

The comment above ext4_get_block_dio_write() ("Maximum number of
blocks...") is a duplicate; the original and correct comment is above
the #define DIO_MAX_BLOCKS up above.

Based on review comments from Curt Wohlgemuth.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

Added to the patch queue

						- Ted