Re: [PATCH 1/5] ext4: Use filemap_write_and_wait_range() correctly in collapse range

Lukáš Czerner
2014-04-16T20:44:22Z

So unfortunately this does not fix all the problems. Even though
this fixes all the problems with collapse rage when page size ==
block size it still fails some tests when page size > block size so
I guess we still have some work to do.

Thanks!
-Lukas

On Wed, 16 Apr 2014, Lukas Czerner wrote:

> Date: Wed, 16 Apr 2014 20:32:58 +0200
> From: Lukas Czerner <lczerner@redhat.com>
> To: linux-ext4@vger.kernel.org
> Cc: linkinjeon@gmail.com, Lukas Czerner <lczerner@redhat.com>
> Subject: [PATCH 1/5] ext4: Use filemap_write_and_wait_range() correctly in
> collapse range
>
> Currently we're passing -1 as lend argumnet for
> filemap_write_and_wait_range() which is wrong since lend is signed type
> so it would cause some confusion and we might not write_and_wait for the
> entire range we're expecting to write.
>
> Fix it by using LLONG_MAX instead.
>
> Signed-off-by: Lukas Czerner <lczerner@redhat.com>
> ---
> fs/ext4/extents.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
> index ff823b7..821c1d4 100644
> --- a/fs/ext4/extents.c
> +++ b/fs/ext4/extents.c
> @@ -5378,7 +5378,7 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
> punch_stop = (offset + len) >> EXT4_BLOCK_SIZE_BITS(sb);
>
> /* Write out all dirty pages */
> - ret = filemap_write_and_wait_range(inode->i_mapping, offset, -1);
> + ret = filemap_write_and_wait_range(inode->i_mapping, offset, LLONG_MAX);
> if (ret)
> return ret;
>
>