From 2f4369a862b637b20ac083a2e674a2d5d1489bda Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 8 Nov 2019 15:05:32 -0800 Subject: xfs: cleanup xfs_dir2_leaf_getdents Use an offset as the main means for iteration, and only do pointer arithmetics to find the data/unused entries. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_dir2_readdir.c | 36 +++++++++++++++++------------------- 1 file changed, 17 insertions(+), 19 deletions(-) diff --git a/fs/xfs/xfs_dir2_readdir.c b/fs/xfs/xfs_dir2_readdir.c index 0d234b649d65..4a29921d8880 100644 --- a/fs/xfs/xfs_dir2_readdir.c +++ b/fs/xfs/xfs_dir2_readdir.c @@ -348,16 +348,15 @@ xfs_dir2_leaf_getdents( { struct xfs_inode *dp = args->dp; struct xfs_buf *bp = NULL; /* data block buffer */ - xfs_dir2_data_hdr_t *hdr; /* data block header */ xfs_dir2_data_entry_t *dep; /* data entry */ xfs_dir2_data_unused_t *dup; /* unused entry */ - char *ptr = NULL; /* pointer to current data */ struct xfs_da_geometry *geo = args->geo; xfs_dablk_t rablk = 0; /* current readahead block */ xfs_dir2_off_t curoff; /* current overall offset */ int length; /* temporary length value */ int byteoff; /* offset in current block */ int lock_mode; + unsigned int offset = 0; int error = 0; /* error return value */ /* @@ -384,7 +383,7 @@ xfs_dir2_leaf_getdents( * If we have no buffer, or we're off the end of the * current buffer, need to get another one. */ - if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) { + if (!bp || offset >= geo->blksize) { if (bp) { xfs_trans_brelse(args->trans, bp); bp = NULL; @@ -397,12 +396,11 @@ xfs_dir2_leaf_getdents( if (error || !bp) break; - hdr = bp->b_addr; xfs_dir3_data_check(dp, bp); /* * Find our position in the block. */ - ptr = (char *)dp->d_ops->data_entry_p(hdr); + offset = dp->d_ops->data_entry_offset; byteoff = xfs_dir2_byte_to_off(geo, curoff); /* * Skip past the header. @@ -413,20 +411,20 @@ xfs_dir2_leaf_getdents( * Skip past entries until we reach our offset. */ else { - while ((char *)ptr - (char *)hdr < byteoff) { - dup = (xfs_dir2_data_unused_t *)ptr; + while (offset < byteoff) { + dup = bp->b_addr + offset; if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { length = be16_to_cpu(dup->length); - ptr += length; + offset += length; continue; } - dep = (xfs_dir2_data_entry_t *)ptr; + dep = bp->b_addr + offset; length = dp->d_ops->data_entsize(dep->namelen); - ptr += length; + offset += length; } /* * Now set our real offset. @@ -434,28 +432,28 @@ xfs_dir2_leaf_getdents( curoff = xfs_dir2_db_off_to_byte(geo, xfs_dir2_byte_to_db(geo, curoff), - (char *)ptr - (char *)hdr); - if (ptr >= (char *)hdr + geo->blksize) { + offset); + if (offset >= geo->blksize) continue; - } } } + /* - * We have a pointer to an entry. - * Is it a live one? + * We have a pointer to an entry. Is it a live one? */ - dup = (xfs_dir2_data_unused_t *)ptr; + dup = bp->b_addr + offset; + /* * No, it's unused, skip over it. */ if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { length = be16_to_cpu(dup->length); - ptr += length; + offset += length; curoff += length; continue; } - dep = (xfs_dir2_data_entry_t *)ptr; + dep = bp->b_addr + offset; length = dp->d_ops->data_entsize(dep->namelen); filetype = dp->d_ops->data_get_ftype(dep); @@ -474,7 +472,7 @@ xfs_dir2_leaf_getdents( /* * Advance to next entry in the block. */ - ptr += length; + offset += length; curoff += length; /* bufsize may have just been a guess; don't go negative */ bufsize = bufsize > length ? bufsize - length : 0; -- cgit v1.2.3