Re: [RFC v3 1/8] ext4: Stop searching if PA doesn't satisfy non-extent file

From: Jan Kara
Date: Thu Sep 29 2022 - 07:25:09 EST


On Tue 27-09-22 14:46:41, Ojaswin Mujoo wrote:
> If we come across a PA that matches the logical offset but is unable to
> satisfy a non-extent file due to its physical start being higher than
> that supported by non extent files, then simply stop searching for
> another PA and break out of loop. This is because, since PAs don't
> overlap, we won't be able to find another inode PA which can satisfy the
> original request.
>
> Signed-off-by: Ojaswin Mujoo <ojaswin@xxxxxxxxxxxxx>
> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

Honza

> ---
> fs/ext4/mballoc.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
> index 71f5b67d7f28..2e3eb632a216 100644
> --- a/fs/ext4/mballoc.c
> +++ b/fs/ext4/mballoc.c
> @@ -4383,8 +4383,13 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac)
> /* non-extent files can't have physical blocks past 2^32 */
> if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS)) &&
> (pa->pa_pstart + EXT4_C2B(sbi, pa->pa_len) >
> - EXT4_MAX_BLOCK_FILE_PHYS))
> - continue;
> + EXT4_MAX_BLOCK_FILE_PHYS)) {
> + /*
> + * Since PAs don't overlap, we won't find any
> + * other PA to satisfy this.
> + */
> + break;
> + }
>
> /* found preallocated blocks, use them */
> spin_lock(&pa->pa_lock);
> --
> 2.31.1
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR