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 <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

1 files changed, 4 insertions, 8 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);