Re: [PATCH 37/46] xfs: replace xfs_dir3_data_endp with xfs_dir3_data_end_offset

Darrick J. Wong
2019-11-08T01:04:26Z

On Thu, Nov 07, 2019 at 07:24:01PM +0100, Christoph Hellwig wrote:
> All the callers really want an offset into the buffer, so adopt
> the helper to return that instead.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

/me feels like he's been walked down the dirent^Wgarden path...

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

--D

> ---
> fs/xfs/libxfs/xfs_dir2.h | 2 +-
> fs/xfs/libxfs/xfs_dir2_data.c | 29 +++++++++++++++--------------
> fs/xfs/libxfs/xfs_dir2_sf.c | 2 +-
> fs/xfs/scrub/dir.c | 10 +++++-----
> fs/xfs/xfs_dir2_readdir.c | 2 +-
> 5 files changed, 23 insertions(+), 22 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_dir2.h b/fs/xfs/libxfs/xfs_dir2.h
> index a160f2d4ff37..3a4b98d4973d 100644
> --- a/fs/xfs/libxfs/xfs_dir2.h
> +++ b/fs/xfs/libxfs/xfs_dir2.h
> @@ -266,7 +266,7 @@ xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
> #define XFS_READDIR_BUFSIZE (32768)
>
> unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
> -void *xfs_dir3_data_endp(struct xfs_da_geometry *geo,
> +unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo,
> struct xfs_dir2_data_hdr *hdr);
> bool xfs_dir2_namecheck(const void *name, size_t length);
>
> diff --git a/fs/xfs/libxfs/xfs_dir2_data.c b/fs/xfs/libxfs/xfs_dir2_data.c
> index 8c729270f9f1..f5fa8b9187b0 100644
> --- a/fs/xfs/libxfs/xfs_dir2_data.c
> +++ b/fs/xfs/libxfs/xfs_dir2_data.c
> @@ -55,7 +55,6 @@ __xfs_dir3_data_check(
> int count; /* count of entries found */
> xfs_dir2_data_hdr_t *hdr; /* data block header */
> xfs_dir2_data_free_t *dfp; /* bestfree entry */
> - void *endp; /* end of useful data */
> int freeseen; /* mask of bestfrees seen */
> xfs_dahash_t hash; /* hash of current name */
> int i; /* leaf index */
> @@ -102,10 +101,9 @@ __xfs_dir3_data_check(
> default:
> return __this_address;
> }
> - endp = xfs_dir3_data_endp(geo, hdr);
> - if (!endp)
> + end = xfs_dir3_data_end_offset(geo, hdr);
> + if (!end)
> return __this_address;
> - end = endp - bp->b_addr;
>
> /*
> * Account for zero bestfree entries.
> @@ -590,7 +588,7 @@ xfs_dir2_data_freescan_int(
> memset(bf, 0, sizeof(*bf) * XFS_DIR2_DATA_FD_COUNT);
> *loghead = 1;
>
> - end = xfs_dir3_data_endp(geo, addr) - addr;
> + end = xfs_dir3_data_end_offset(geo, addr);
> while (offset < end) {
> struct xfs_dir2_data_unused *dup = addr + offset;
> struct xfs_dir2_data_entry *dep = addr + offset;
> @@ -784,11 +782,11 @@ xfs_dir2_data_make_free(
> {
> xfs_dir2_data_hdr_t *hdr; /* data block pointer */
> xfs_dir2_data_free_t *dfp; /* bestfree pointer */
> - char *endptr; /* end of data area */
> int needscan; /* need to regen bestfree */
> xfs_dir2_data_unused_t *newdup; /* new unused entry */
> xfs_dir2_data_unused_t *postdup; /* unused entry after us */
> xfs_dir2_data_unused_t *prevdup; /* unused entry before us */
> + unsigned int end;
> struct xfs_dir2_data_free *bf;
>
> hdr = bp->b_addr;
> @@ -796,8 +794,8 @@ xfs_dir2_data_make_free(
> /*
> * Figure out where the end of the data area is.
> */
> - endptr = xfs_dir3_data_endp(args->geo, hdr);
> - ASSERT(endptr != NULL);
> + end = xfs_dir3_data_end_offset(args->geo, hdr);
> + ASSERT(end != 0);
>
> /*
> * If this isn't the start of the block, then back up to
> @@ -816,7 +814,7 @@ xfs_dir2_data_make_free(
> * If this isn't the end of the block, see if the entry after
> * us is free.
> */
> - if ((char *)hdr + offset + len < endptr) {
> + if (offset + len < end) {
> postdup =
> (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
> if (be16_to_cpu(postdup->freetag) != XFS_DIR2_DATA_FREE_TAG)
> @@ -1144,19 +1142,22 @@ xfs_dir2_data_use_free(
> }
>
> /* Find the end of the entry data in a data/block format dir block. */
> -void *
> -xfs_dir3_data_endp(
> +unsigned int
> +xfs_dir3_data_end_offset(
> struct xfs_da_geometry *geo,
> struct xfs_dir2_data_hdr *hdr)
> {
> + void *p;
> +
> switch (hdr->magic) {
> case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC):
> case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC):
> - return xfs_dir2_block_leaf_p(xfs_dir2_block_tail_p(geo, hdr));
> + p = xfs_dir2_block_leaf_p(xfs_dir2_block_tail_p(geo, hdr));
> + return p - (void *)hdr;
> case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
> case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
> - return (char *)hdr + geo->blksize;
> + return geo->blksize;
> default:
> - return NULL;
> + return 0;
> }
> }
> diff --git a/fs/xfs/libxfs/xfs_dir2_sf.c b/fs/xfs/libxfs/xfs_dir2_sf.c
> index a1aed589dc8c..bb6491a3c473 100644
> --- a/fs/xfs/libxfs/xfs_dir2_sf.c
> +++ b/fs/xfs/libxfs/xfs_dir2_sf.c
> @@ -283,7 +283,7 @@ xfs_dir2_block_to_sf(
> * Loop over the active and unused entries. Stop when we reach the
> * leaf/tail portion of the block.
> */
> - end = xfs_dir3_data_endp(args->geo, bp->b_addr) - bp->b_addr;
> + end = xfs_dir3_data_end_offset(args->geo, bp->b_addr);
> sfep = xfs_dir2_sf_firstentry(sfp);
> while (offset < end) {
> struct xfs_dir2_data_unused *dup = bp->b_addr + offset;
> diff --git a/fs/xfs/scrub/dir.c b/fs/xfs/scrub/dir.c
> index 4cef21b9d336..7f03f0fb178a 100644
> --- a/fs/xfs/scrub/dir.c
> +++ b/fs/xfs/scrub/dir.c
> @@ -187,7 +187,7 @@ xchk_dir_rec(
> struct xfs_dir2_data_entry *dent;
> struct xfs_buf *bp;
> struct xfs_dir2_leaf_entry *ent;
> - void *endp;
> + unsigned int end;
> unsigned int offset;
> xfs_ino_t ino;
> xfs_dablk_t rec_bno;
> @@ -242,8 +242,8 @@ xchk_dir_rec(
>
> /* Make sure we got a real directory entry. */
> offset = mp->m_dir_inode_ops->data_entry_offset;
> - endp = xfs_dir3_data_endp(mp->m_dir_geo, bp->b_addr);
> - if (!endp) {
> + end = xfs_dir3_data_end_offset(mp->m_dir_geo, bp->b_addr);
> + if (!end) {
> xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
> goto out_relse;
> }
> @@ -251,7 +251,7 @@ xchk_dir_rec(
> struct xfs_dir2_data_entry *dep = bp->b_addr + offset;
> struct xfs_dir2_data_unused *dup = bp->b_addr + offset;
>
> - if (offset >= endp - bp->b_addr) {
> + if (offset >= end) {
> xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
> goto out_relse;
> }
> @@ -390,7 +390,7 @@ xchk_directory_data_bestfree(
>
> /* Make sure the bestfrees are actually the best free spaces. */
> offset = d_ops->data_entry_offset;
> - end = xfs_dir3_data_endp(mp->m_dir_geo, bp->b_addr) - bp->b_addr;
> + end = xfs_dir3_data_end_offset(mp->m_dir_geo, bp->b_addr);
>
> /* Iterate the entries, stopping when we hit or go past the end. */
> while (offset < end) {
> diff --git a/fs/xfs/xfs_dir2_readdir.c b/fs/xfs/xfs_dir2_readdir.c
> index c4314e9e3dd8..6d229aa93d01 100644
> --- a/fs/xfs/xfs_dir2_readdir.c
> +++ b/fs/xfs/xfs_dir2_readdir.c
> @@ -175,7 +175,7 @@ xfs_dir2_block_getdents(
> * Each object is a real entry (dep) or an unused one (dup).
> */
> offset = dp->d_ops->data_entry_offset;
> - end = xfs_dir3_data_endp(geo, bp->b_addr) - bp->b_addr;
> + end = xfs_dir3_data_end_offset(geo, bp->b_addr);
> while (offset < end) {
> struct xfs_dir2_data_unused *dup = bp->b_addr + offset;
> struct xfs_dir2_data_entry *dep = bp->b_addr + offset;
> --
> 2.20.1
>