Re: [PATCH 08/19] xfs: indicate if xfs_bmap_adjacent changed ap->blkno

Darrick J. Wong
2023-12-14T20:52:23Z

On Thu, Dec 14, 2023 at 07:34:27AM +0100, Christoph Hellwig wrote:
> Add a return value to xfs_bmap_adjacent to indicate if it did change
> ap->blkno or not.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks fine to me, though I don't see any immediate callsite changes so I
guess I'll look out for whatever uses the return value.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> ---
> fs/xfs/libxfs/xfs_bmap.c | 19 ++++++++++++++-----
> fs/xfs/xfs_bmap_util.h | 2 +-
> 2 files changed, 15 insertions(+), 6 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
> index 6722205949ad4c..46a9b22a3733e3 100644
> --- a/fs/xfs/libxfs/xfs_bmap.c
> +++ b/fs/xfs/libxfs/xfs_bmap.c
> @@ -3044,7 +3044,8 @@ xfs_bmap_extsize_align(
>
> #define XFS_ALLOC_GAP_UNITS 4
>
> -void
> +/* returns true if ap->blkno was modified */
> +bool
> xfs_bmap_adjacent(
> struct xfs_bmalloca *ap) /* bmap alloc argument struct */
> {
> @@ -3079,13 +3080,14 @@ xfs_bmap_adjacent(
> if (adjust &&
> ISVALID(ap->blkno + adjust, ap->prev.br_startblock))
> ap->blkno += adjust;
> + return true;
> }
> /*
> * If not at eof, then compare the two neighbor blocks.
> * Figure out whether either one gives us a good starting point,
> * and pick the better one.
> */
> - else if (!ap->eof) {
> + if (!ap->eof) {
> xfs_fsblock_t gotbno; /* right side block number */
> xfs_fsblock_t gotdiff=0; /* right side difference */
> xfs_fsblock_t prevbno; /* left side block number */
> @@ -3165,14 +3167,21 @@ xfs_bmap_adjacent(
> * If both valid, pick the better one, else the only good
> * one, else ap->blkno is already set (to 0 or the inode block).
> */
> - if (prevbno != NULLFSBLOCK && gotbno != NULLFSBLOCK)
> + if (prevbno != NULLFSBLOCK && gotbno != NULLFSBLOCK) {
> ap->blkno = prevdiff <= gotdiff ? prevbno : gotbno;
> - else if (prevbno != NULLFSBLOCK)
> + return true;
> + }
> + if (prevbno != NULLFSBLOCK) {
> ap->blkno = prevbno;
> - else if (gotbno != NULLFSBLOCK)
> + return true;
> + }
> + if (gotbno != NULLFSBLOCK) {
> ap->blkno = gotbno;
> + return true;
> + }
> }
> #undef ISVALID
> + return false;
> }
>
> int
> diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h
> index 6888078f5c31e0..77ecbb753ef207 100644
> --- a/fs/xfs/xfs_bmap_util.h
> +++ b/fs/xfs/xfs_bmap_util.h
> @@ -47,7 +47,7 @@ int xfs_bmap_extsize_align(struct xfs_mount *mp, struct xfs_bmbt_irec *gotp,
> struct xfs_bmbt_irec *prevp, xfs_extlen_t extsz,
> int rt, int eof, int delay, int convert,
> xfs_fileoff_t *offp, xfs_extlen_t *lenp);
> -void xfs_bmap_adjacent(struct xfs_bmalloca *ap);
> +bool xfs_bmap_adjacent(struct xfs_bmalloca *ap);
> int xfs_bmap_last_extent(struct xfs_trans *tp, struct xfs_inode *ip,
> int whichfork, struct xfs_bmbt_irec *rec,
> int *is_empty);
> --
> 2.39.2
>
>