From a64b04179735de6bfd9f00c130a68ed7f20d18ef Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 8 Jul 2011 14:35:32 +0200 Subject: [PATCH] xfs: kill struct xfs_dir2_block Remove the confusing xfs_dir2_block structure. It is supposed to describe an XFS dir2 block format btree block, but due to the variable sized nature of almost all elements in it it can't actuall do anything close to that job. In addition to accessing the fixed offset header structure it was only used to get a pointer to the first dir or unused entry after it, which can be trivially replaced by pointer arithmetics on the header pointer. For most users that is actually more natural anyway, as they don't use a typed pointer but rather a character pointer for further arithmetics. Signed-off-by: Christoph Hellwig Reviewed-by: Alex Elder Reviewed-by: Dave Chinner --- fs/xfs/xfs_dir2_block.c | 12 ++++------- fs/xfs/xfs_dir2_block.h | 44 +++++++++++++++++++++-------------------- fs/xfs/xfs_dir2_sf.c | 14 ++++++------- 3 files changed, 34 insertions(+), 36 deletions(-) diff --git a/fs/xfs/xfs_dir2_block.c b/fs/xfs/xfs_dir2_block.c index a0037cc4dd8c..9adaf803957a 100644 --- a/fs/xfs/xfs_dir2_block.c +++ b/fs/xfs/xfs_dir2_block.c @@ -437,7 +437,6 @@ xfs_dir2_block_getdents( xfs_off_t *offset, filldir_t filldir) { - xfs_dir2_block_t *block; /* directory block structure */ xfs_dir2_data_hdr_t *hdr; /* block header */ xfs_dabuf_t *bp; /* buffer for block */ xfs_dir2_block_tail_t *btp; /* block tail */ @@ -471,14 +470,13 @@ xfs_dir2_block_getdents( * We'll skip entries before this. */ wantoff = xfs_dir2_dataptr_to_off(mp, *offset); - block = bp->data; - hdr = &block->hdr; + hdr = bp->data; xfs_dir2_data_check(dp, bp); /* * Set up values for the loop. */ btp = xfs_dir2_block_tail_p(mp, hdr); - ptr = (char *)block->u; + ptr = (char *)(hdr + 1); endptr = (char *)xfs_dir2_block_leaf_p(btp); /* @@ -1020,7 +1018,6 @@ xfs_dir2_sf_to_block( xfs_da_args_t *args) /* operation arguments */ { xfs_dir2_db_t blkno; /* dir-relative block # (0) */ - xfs_dir2_block_t *block; /* block structure */ xfs_dir2_data_hdr_t *hdr; /* block header */ xfs_dir2_leaf_entry_t *blp; /* block leaf entries */ xfs_dabuf_t *bp; /* block buffer */ @@ -1091,8 +1088,7 @@ xfs_dir2_sf_to_block( kmem_free(sfp); return error; } - block = bp->data; - hdr = &block->hdr; + hdr = bp->data; hdr->magic = cpu_to_be32(XFS_DIR2_BLOCK_MAGIC); /* * Compute size of block "tail" area. @@ -1103,7 +1099,7 @@ xfs_dir2_sf_to_block( * The whole thing is initialized to free by the init routine. * Say we're using the leaf and tail area. */ - dup = (xfs_dir2_data_unused_t *)block->u; + dup = (xfs_dir2_data_unused_t *)(hdr + 1); needlog = needscan = 0; xfs_dir2_data_use_free(tp, bp, dup, mp->m_dirblksize - i, i, &needlog, &needscan); diff --git a/fs/xfs/xfs_dir2_block.h b/fs/xfs/xfs_dir2_block.h index fe91f88f880c..de59677e38ba 100644 --- a/fs/xfs/xfs_dir2_block.h +++ b/fs/xfs/xfs_dir2_block.h @@ -19,10 +19,30 @@ #define __XFS_DIR2_BLOCK_H__ /* - * xfs_dir2_block.h - * Directory version 2, single block format structures + * Directory version 2, single block format structures. + * + * The single block format looks like the following drawing on disk: + * + * +-------------------------------------------------+ + * | xfs_dir2_data_hdr_t | + * +-------------------------------------------------+ + * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | + * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | + * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | + * | ... | + * +-------------------------------------------------+ + * | unused space | + * +-------------------------------------------------+ + * | ... | + * | xfs_dir2_leaf_entry_t | + * | xfs_dir2_leaf_entry_t | + * +-------------------------------------------------+ + * | xfs_dir2_block_tail_t | + * +-------------------------------------------------+ + * + * As all the entries are variable size structures the accessors in this + * file and xfs_dir2_data.h should be used to iterate over them. */ - struct uio; struct xfs_dabuf; struct xfs_da_args; @@ -32,14 +52,6 @@ struct xfs_inode; struct xfs_mount; struct xfs_trans; -/* - * The single block format is as follows: - * xfs_dir2_data_hdr_t structure - * xfs_dir2_data_entry_t and xfs_dir2_data_unused_t structures - * xfs_dir2_leaf_entry_t structures - * xfs_dir2_block_tail_t structure - */ - #define XFS_DIR2_BLOCK_MAGIC 0x58443242 /* XD2B: for one block dirs */ typedef struct xfs_dir2_block_tail { @@ -47,16 +59,6 @@ typedef struct xfs_dir2_block_tail { __be32 stale; /* count of stale lf entries */ } xfs_dir2_block_tail_t; -/* - * Generic single-block structure, for xfs_db. - */ -typedef struct xfs_dir2_block { - xfs_dir2_data_hdr_t hdr; /* magic XFS_DIR2_BLOCK_MAGIC */ - xfs_dir2_data_union_t u[1]; - xfs_dir2_leaf_entry_t leaf[1]; - xfs_dir2_block_tail_t tail; -} xfs_dir2_block_t; - /* * Pointer to the leaf header embedded in a data block (1-block format) */ diff --git a/fs/xfs/xfs_dir2_sf.c b/fs/xfs/xfs_dir2_sf.c index 515efa5d29ca..b47a99c8f244 100644 --- a/fs/xfs/xfs_dir2_sf.c +++ b/fs/xfs/xfs_dir2_sf.c @@ -226,7 +226,7 @@ xfs_dir2_block_to_sf( int size, /* shortform directory size */ xfs_dir2_sf_hdr_t *sfhp) /* shortform directory hdr */ { - xfs_dir2_block_t *block; /* block structure */ + xfs_dir2_data_hdr_t *hdr; /* block header */ xfs_dir2_block_tail_t *btp; /* block tail pointer */ xfs_dir2_data_entry_t *dep; /* data entry pointer */ xfs_inode_t *dp; /* incore directory inode */ @@ -248,8 +248,8 @@ xfs_dir2_block_to_sf( * Make a copy of the block data, so we can shrink the inode * and add local data. */ - block = kmem_alloc(mp->m_dirblksize, KM_SLEEP); - memcpy(block, bp->data, mp->m_dirblksize); + hdr = kmem_alloc(mp->m_dirblksize, KM_SLEEP); + memcpy(hdr, bp->data, mp->m_dirblksize); logflags = XFS_ILOG_CORE; if ((error = xfs_dir2_shrink_inode(args, mp->m_dirdatablk, bp))) { ASSERT(error != ENOSPC); @@ -277,8 +277,8 @@ xfs_dir2_block_to_sf( /* * Set up to loop over the block's entries. */ - btp = xfs_dir2_block_tail_p(mp, &block->hdr); - ptr = (char *)block->u; + btp = xfs_dir2_block_tail_p(mp, hdr); + ptr = (char *)(hdr + 1); endptr = (char *)xfs_dir2_block_leaf_p(btp); sfep = xfs_dir2_sf_firstentry(sfp); /* @@ -314,7 +314,7 @@ xfs_dir2_block_to_sf( sfep->namelen = dep->namelen; xfs_dir2_sf_put_offset(sfep, (xfs_dir2_data_aoff_t) - ((char *)dep - (char *)block)); + ((char *)dep - (char *)hdr)); memcpy(sfep->name, dep->name, dep->namelen); xfs_dir2_sfe_put_ino(sfp, sfep, be64_to_cpu(dep->inumber)); @@ -327,7 +327,7 @@ xfs_dir2_block_to_sf( xfs_dir2_sf_check(args); out: xfs_trans_log_inode(args->trans, dp, logflags); - kmem_free(block); + kmem_free(hdr); return error; } -- 2.39.5