[XFS] Always use struct xfs_btree_block instead of short / longform

structures.

Always use the generic xfs_btree_block type instead of the short / long
structures. Add XFS_BTREE_SBLOCK_LEN / XFS_BTREE_LBLOCK_LEN defines for
the length of a short / long form block. The rationale for this is that we
will grow more btree block header variants to support CRCs and other RAS
information, and always accessing them through the same datatype with
unions for the short / long form pointers makes implementing this much
easier.

SGI-PV: 988146

SGI-Modid: xfs-linux-melb:xfs-kern:32300a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

15 files changed, 165 insertions, 187 deletions

diff --git a/fs/xfs/xfs_alloc.c b/fs/xfs/xfs_alloc.c
index 0a2a87208b17..c47ce9075728 100644
--- a/fs/xfs/xfs_alloc.c
+++ b/fs/xfs/xfs_alloc.c
@@ -380,21 +380,20 @@ xfs_alloc_fixup_trees(
                         return error;
                 XFS_WANT_CORRUPTED_RETURN(i == 1);
         }
+
 #ifdef DEBUG
-        {
-                xfs_alloc_block_t       *bnoblock;
-                xfs_alloc_block_t       *cntblock;
-
-                if (bno_cur->bc_nlevels == 1 &&
-                    cnt_cur->bc_nlevels == 1) {
-                        bnoblock = XFS_BUF_TO_ALLOC_BLOCK(bno_cur->bc_bufs[0]);
-                        cntblock = XFS_BUF_TO_ALLOC_BLOCK(cnt_cur->bc_bufs[0]);
-                        XFS_WANT_CORRUPTED_RETURN(
-                                be16_to_cpu(bnoblock->bb_numrecs) ==
-                                be16_to_cpu(cntblock->bb_numrecs));
-                }
+        if (bno_cur->bc_nlevels == 1 && cnt_cur->bc_nlevels == 1) {
+                struct xfs_btree_block  *bnoblock;
+                struct xfs_btree_block  *cntblock;
+
+                bnoblock = XFS_BUF_TO_BLOCK(bno_cur->bc_bufs[0]);
+                cntblock = XFS_BUF_TO_BLOCK(cnt_cur->bc_bufs[0]);
+
+                XFS_WANT_CORRUPTED_RETURN(
+                        bnoblock->bb_numrecs == cntblock->bb_numrecs);
         }
 #endif
+
         /*
          * Deal with all four cases: the allocated record is contained
          * within the freespace record, so we can have new freespace
diff --git a/fs/xfs/xfs_alloc_btree.c b/fs/xfs/xfs_alloc_btree.c
index 72c083f62a94..733cb75a8c5d 100644
--- a/fs/xfs/xfs_alloc_btree.c
+++ b/fs/xfs/xfs_alloc_btree.c
@@ -490,7 +490,7 @@ xfs_allocbt_maxrecs(
         int                     blocklen,
         int                     leaf)
 {
-        blocklen -= sizeof(struct xfs_btree_sblock);
+        blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
 
         if (leaf)
                 return blocklen / sizeof(xfs_alloc_rec_t);
diff --git a/fs/xfs/xfs_alloc_btree.h b/fs/xfs/xfs_alloc_btree.h
index 579f9c7e0872..a6caa0022c9b 100644
--- a/fs/xfs/xfs_alloc_btree.h
+++ b/fs/xfs/xfs_alloc_btree.h
@@ -24,7 +24,6 @@
 
 struct xfs_buf;
 struct xfs_btree_cur;
-struct xfs_btree_sblock;
 struct xfs_mount;
 
 /*
@@ -50,10 +49,6 @@ typedef struct xfs_alloc_rec_incore {
 
 /* btree pointer type */
 typedef __be32 xfs_alloc_ptr_t;
-/* btree block header type */
-typedef struct xfs_btree_sblock xfs_alloc_block_t;
-
-#define XFS_BUF_TO_ALLOC_BLOCK(bp)      ((xfs_alloc_block_t *)XFS_BUF_PTR(bp))
 
 /*
  * Minimum and maximum blocksize and sectorsize.
@@ -77,6 +72,13 @@ typedef	struct xfs_btree_sblock xfs_alloc_block_t;
 #define XFS_CNT_BLOCK(mp)       ((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
 
 /*
+ * Btree block header size depends on a superblock flag.
+ *
+ * (not quite yet, but soon)
+ */
+#define XFS_ALLOC_BLOCK_LEN(mp) XFS_BTREE_SBLOCK_LEN
+
+/*
  * Record, key, and pointer address macros for btree blocks.
  *
  * (note that some of these may appear unused, but they are used in userspace)
@@ -84,19 +86,19 @@ typedef	struct xfs_btree_sblock xfs_alloc_block_t;
 #define XFS_ALLOC_REC_ADDR(mp, block, index) \
         ((xfs_alloc_rec_t *) \
                 ((char *)(block) + \
-                 sizeof(struct xfs_btree_sblock) + \
+                 XFS_ALLOC_BLOCK_LEN(mp) + \
                  (((index) - 1) * sizeof(xfs_alloc_rec_t))))
 
 #define XFS_ALLOC_KEY_ADDR(mp, block, index) \
         ((xfs_alloc_key_t *) \
                 ((char *)(block) + \
-                 sizeof(struct xfs_btree_sblock) + \
+                 XFS_ALLOC_BLOCK_LEN(mp) + \
                  ((index) - 1) * sizeof(xfs_alloc_key_t)))
 
 #define XFS_ALLOC_PTR_ADDR(mp, block, index, maxrecs) \
         ((xfs_alloc_ptr_t *) \
                 ((char *)(block) + \
-                 sizeof(struct xfs_btree_sblock) + \
+                 XFS_ALLOC_BLOCK_LEN(mp) + \
                  (maxrecs) * sizeof(xfs_alloc_key_t) + \
                  ((index) - 1) * sizeof(xfs_alloc_ptr_t)))
 
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index 3dab937d4b85..7796a0c140eb 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -394,7 +394,7 @@ xfs_bmap_count_leaves(
 STATIC void
 xfs_bmap_disk_count_leaves(
         struct xfs_mount        *mp,
-        xfs_bmbt_block_t        *block,
+        struct xfs_btree_block  *block,
         int                     numrecs,
         int                     *count);
 
@@ -3042,14 +3042,14 @@ xfs_bmap_btree_to_extents(
         int                     whichfork)  /* data or attr fork */
 {
         /* REFERENCED */
-        xfs_bmbt_block_t        *cblock;/* child btree block */
+        struct xfs_btree_block  *cblock;/* child btree block */
         xfs_fsblock_t           cbno;   /* child block number */
         xfs_buf_t               *cbp;   /* child block's buffer */
         int                     error;  /* error return value */
         xfs_ifork_t             *ifp;   /* inode fork data */
         xfs_mount_t             *mp;    /* mount point structure */
         __be64                  *pp;    /* ptr to block address */
-        xfs_bmbt_block_t        *rblock;/* root btree block */
+        struct xfs_btree_block  *rblock;/* root btree block */
 
         mp = ip->i_mount;
         ifp = XFS_IFORK_PTR(ip, whichfork);
@@ -3069,8 +3069,8 @@ xfs_bmap_btree_to_extents(
         if ((error = xfs_btree_read_bufl(mp, tp, cbno, 0, &cbp,
                         XFS_BMAP_BTREE_REF)))
                 return error;
-        cblock = XFS_BUF_TO_BMBT_BLOCK(cbp);
-        if ((error = xfs_btree_check_lblock(cur, cblock, 0, cbp)))
+        cblock = XFS_BUF_TO_BLOCK(cbp);
+        if ((error = xfs_btree_check_block(cur, cblock, 0, cbp)))
                 return error;
         xfs_bmap_add_free(cbno, 1, cur->bc_private.b.flist, mp);
         ip->i_d.di_nblocks--;
@@ -3450,11 +3450,11 @@ xfs_bmap_extents_to_btree(
         int                     *logflagsp,     /* inode logging flags */
         int                     whichfork)      /* data or attr fork */
 {
-        xfs_bmbt_block_t        *ablock;        /* allocated (child) bt block */
+        struct xfs_btree_block  *ablock;        /* allocated (child) bt block */
         xfs_buf_t               *abp;           /* buffer for ablock */
         xfs_alloc_arg_t         args;           /* allocation arguments */
         xfs_bmbt_rec_t          *arp;           /* child record pointer */
-        xfs_bmbt_block_t        *block;         /* btree root block */
+        struct xfs_btree_block  *block;         /* btree root block */
         xfs_btree_cur_t         *cur;           /* bmap btree cursor */
         xfs_bmbt_rec_host_t     *ep;            /* extent record pointer */
         int                     error;          /* error return value */
@@ -3474,6 +3474,7 @@ xfs_bmap_extents_to_btree(
          */
         xfs_iroot_realloc(ip, 1, whichfork);
         ifp->if_flags |= XFS_IFBROOT;
+
         /*
          * Fill in the root.
          */
@@ -3481,8 +3482,9 @@ xfs_bmap_extents_to_btree(
         block->bb_magic = cpu_to_be32(XFS_BMAP_MAGIC);
         block->bb_level = cpu_to_be16(1);
         block->bb_numrecs = cpu_to_be16(1);
-        block->bb_leftsib = cpu_to_be64(NULLDFSBNO);
-        block->bb_rightsib = cpu_to_be64(NULLDFSBNO);
+        block->bb_u.l.bb_leftsib = cpu_to_be64(NULLDFSBNO);
+        block->bb_u.l.bb_rightsib = cpu_to_be64(NULLDFSBNO);
+
         /*
          * Need a cursor.  Can't allocate until bb_level is filled in.
          */
@@ -3534,11 +3536,11 @@ xfs_bmap_extents_to_btree(
         /*
          * Fill in the child block.
          */
-        ablock = XFS_BUF_TO_BMBT_BLOCK(abp);
+        ablock = XFS_BUF_TO_BLOCK(abp);
         ablock->bb_magic = cpu_to_be32(XFS_BMAP_MAGIC);
         ablock->bb_level = 0;
-        ablock->bb_leftsib = cpu_to_be64(NULLDFSBNO);
-        ablock->bb_rightsib = cpu_to_be64(NULLDFSBNO);
+        ablock->bb_u.l.bb_leftsib = cpu_to_be64(NULLDFSBNO);
+        ablock->bb_u.l.bb_rightsib = cpu_to_be64(NULLDFSBNO);
         arp = XFS_BMBT_REC_ADDR(mp, ablock, 1);
         nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
         for (cnt = i = 0; i < nextents; i++) {
@@ -3550,7 +3552,8 @@ xfs_bmap_extents_to_btree(
                 }
         }
         ASSERT(cnt == XFS_IFORK_NEXTENTS(ip, whichfork));
-        ablock->bb_numrecs = cpu_to_be16(cnt);
+        xfs_btree_set_numrecs(ablock, cnt);
+
         /*
          * Fill in the root key and pointer.
          */
@@ -4533,7 +4536,7 @@ xfs_bmap_read_extents(
         xfs_inode_t             *ip,    /* incore inode */
         int                     whichfork) /* data or attr fork */
 {
-        xfs_bmbt_block_t        *block; /* current btree block */
+        struct xfs_btree_block  *block; /* current btree block */
         xfs_fsblock_t           bno;    /* block # of "block" */
         xfs_buf_t               *bp;    /* buffer for "block" */
         int                     error;  /* error return value */
@@ -4570,7 +4573,7 @@ xfs_bmap_read_extents(
                 if ((error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
                                 XFS_BMAP_BTREE_REF)))
                         return error;
-                block = XFS_BUF_TO_BMBT_BLOCK(bp);
+                block = XFS_BUF_TO_BLOCK(bp);
                 XFS_WANT_CORRUPTED_GOTO(
                         XFS_BMAP_SANITY_CHECK(mp, block, level),
                         error0);
@@ -4596,7 +4599,7 @@ xfs_bmap_read_extents(
                 xfs_extnum_t    start;
 
 
-                num_recs = be16_to_cpu(block->bb_numrecs);
+                num_recs = xfs_btree_get_numrecs(block);
                 if (unlikely(i + num_recs > room)) {
                         ASSERT(i + num_recs <= room);
                         xfs_fs_repair_cmn_err(CE_WARN, ip->i_mount,
@@ -4613,7 +4616,7 @@ xfs_bmap_read_extents(
                 /*
                  * Read-ahead the next leaf block, if any.
                  */
-                nextbno = be64_to_cpu(block->bb_rightsib);
+                nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
                 if (nextbno != NULLFSBLOCK)
                         xfs_btree_reada_bufl(mp, nextbno, 1);
                 /*
@@ -4650,7 +4653,7 @@ xfs_bmap_read_extents(
                 if ((error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
                                 XFS_BMAP_BTREE_REF)))
                         return error;
-                block = XFS_BUF_TO_BMBT_BLOCK(bp);
+                block = XFS_BUF_TO_BLOCK(bp);
         }
         ASSERT(i == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)));
         ASSERT(i == XFS_IFORK_NEXTENTS(ip, whichfork));
@@ -6175,7 +6178,7 @@ xfs_bmap_get_bp(
 
 void
 xfs_check_block(
-        xfs_bmbt_block_t        *block,
+        struct xfs_btree_block  *block,
         xfs_mount_t             *mp,
         int                     root,
         short                   sz)
@@ -6187,7 +6190,7 @@ xfs_check_block(
         ASSERT(be16_to_cpu(block->bb_level) > 0);
 
         prevp = NULL;
-        for( i = 1; i <= be16_to_cpu(block->bb_numrecs); i++) {
+        for( i = 1; i <= xfs_btree_get_numrecs(block); i++) {
                 dmxr = mp->m_bmap_dmxr[0];
                 keyp = XFS_BMBT_KEY_ADDR(mp, block, i);
 
@@ -6232,7 +6235,7 @@ xfs_bmap_check_leaf_extents(
         xfs_inode_t             *ip,            /* incore inode pointer */
         int                     whichfork)      /* data or attr fork */
 {
-        xfs_bmbt_block_t        *block; /* current btree block */
+        struct xfs_btree_block  *block; /* current btree block */
         xfs_fsblock_t           bno;    /* block # of "block" */
         xfs_buf_t               *bp;    /* buffer for "block" */
         int                     error;  /* error return value */
@@ -6282,7 +6285,7 @@ xfs_bmap_check_leaf_extents(
                 if (!bp && (error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
                                 XFS_BMAP_BTREE_REF)))
                         goto error_norelse;
-                block = XFS_BUF_TO_BMBT_BLOCK(bp);
+                block = XFS_BUF_TO_BLOCK(bp);
                 XFS_WANT_CORRUPTED_GOTO(
                         XFS_BMAP_SANITY_CHECK(mp, block, level),
                         error0);
@@ -6317,13 +6320,13 @@ xfs_bmap_check_leaf_extents(
                 xfs_extnum_t    num_recs;
 
 
-                num_recs = be16_to_cpu(block->bb_numrecs);
+                num_recs = xfs_btree_get_numrecs(block);
 
                 /*
                  * Read-ahead the next leaf block, if any.
                  */
 
-                nextbno = be64_to_cpu(block->bb_rightsib);
+                nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
 
                 /*
                  * Check all the extents to make sure they are OK.
@@ -6367,7 +6370,7 @@ xfs_bmap_check_leaf_extents(
                 if (!bp && (error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
                                 XFS_BMAP_BTREE_REF)))
                         goto error_norelse;
-                block = XFS_BUF_TO_BMBT_BLOCK(bp);
+                block = XFS_BUF_TO_BLOCK(bp);
         }
         if (bp_release) {
                 bp_release = 0;
@@ -6397,7 +6400,7 @@ xfs_bmap_count_blocks(
         int                     whichfork,      /* data or attr fork */
         int                     *count)         /* out: count of blocks */
 {
-        xfs_bmbt_block_t        *block; /* current btree block */
+        struct xfs_btree_block  *block; /* current btree block */
         xfs_fsblock_t           bno;    /* block # of "block" */
         xfs_ifork_t             *ifp;   /* fork structure */
         int                     level;  /* btree level, for checking */
@@ -6454,24 +6457,24 @@ xfs_bmap_count_tree(
         __be64                  *pp;
         xfs_fsblock_t           bno = blockno;
         xfs_fsblock_t           nextbno;
-        xfs_bmbt_block_t        *block, *nextblock;
+        struct xfs_btree_block  *block, *nextblock;
         int                     numrecs;
 
         if ((error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp, XFS_BMAP_BTREE_REF)))
                 return error;
         *count += 1;
-        block = XFS_BUF_TO_BMBT_BLOCK(bp);
+        block = XFS_BUF_TO_BLOCK(bp);
 
         if (--level) {
                 /* Not at node above leafs, count this level of nodes */
-                nextbno = be64_to_cpu(block->bb_rightsib);
+                nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
                 while (nextbno != NULLFSBLOCK) {
                         if ((error = xfs_btree_read_bufl(mp, tp, nextbno,
                                 0, &nbp, XFS_BMAP_BTREE_REF)))
                                 return error;
                         *count += 1;
-                        nextblock = XFS_BUF_TO_BMBT_BLOCK(nbp);
-                        nextbno = be64_to_cpu(nextblock->bb_rightsib);
+                        nextblock = XFS_BUF_TO_BLOCK(nbp);
+                        nextbno = be64_to_cpu(nextblock->bb_u.l.bb_rightsib);
                         xfs_trans_brelse(tp, nbp);
                 }
 
@@ -6489,7 +6492,7 @@ xfs_bmap_count_tree(
         } else {
                 /* count all level 1 nodes and their leaves */
                 for (;;) {
-                        nextbno = be64_to_cpu(block->bb_rightsib);
+                        nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
                         numrecs = be16_to_cpu(block->bb_numrecs);
                         xfs_bmap_disk_count_leaves(mp, block, numrecs, count);
                         xfs_trans_brelse(tp, bp);
@@ -6500,7 +6503,7 @@ xfs_bmap_count_tree(
                                 XFS_BMAP_BTREE_REF)))
                                 return error;
                         *count += 1;
-                        block = XFS_BUF_TO_BMBT_BLOCK(bp);
+                        block = XFS_BUF_TO_BLOCK(bp);
                 }
         }
         return 0;
@@ -6531,7 +6534,7 @@ xfs_bmap_count_leaves(
 STATIC void
 xfs_bmap_disk_count_leaves(
         struct xfs_mount        *mp,
-        xfs_bmbt_block_t        *block,
+        struct xfs_btree_block  *block,
         int                     numrecs,
         int                     *count)
 {
diff --git a/fs/xfs/xfs_bmap_btree.c b/fs/xfs/xfs_bmap_btree.c
index 11137c042c94..e46e02b8e277 100644
--- a/fs/xfs/xfs_bmap_btree.c
+++ b/fs/xfs/xfs_bmap_btree.c
@@ -68,7 +68,7 @@ xfs_bmdr_to_bmbt(
         struct xfs_mount        *mp,
         xfs_bmdr_block_t        *dblock,
         int                     dblocklen,
-        xfs_bmbt_block_t        *rblock,
+        struct xfs_btree_block  *rblock,
         int                     rblocklen)
 {
         int                     dmxr;
@@ -81,8 +81,8 @@ xfs_bmdr_to_bmbt(
         rblock->bb_level = dblock->bb_level;
         ASSERT(be16_to_cpu(rblock->bb_level) > 0);
         rblock->bb_numrecs = dblock->bb_numrecs;
-        rblock->bb_leftsib = cpu_to_be64(NULLDFSBNO);
-        rblock->bb_rightsib = cpu_to_be64(NULLDFSBNO);
+        rblock->bb_u.l.bb_leftsib = cpu_to_be64(NULLDFSBNO);
+        rblock->bb_u.l.bb_rightsib = cpu_to_be64(NULLDFSBNO);
         dmxr = xfs_bmdr_maxrecs(mp, dblocklen, 0);
         fkp = XFS_BMDR_KEY_ADDR(dblock, 1);
         tkp = XFS_BMBT_KEY_ADDR(mp, rblock, 1);
@@ -429,7 +429,7 @@ xfs_bmbt_set_state(
 void
 xfs_bmbt_to_bmdr(
         struct xfs_mount        *mp,
-        xfs_bmbt_block_t        *rblock,
+        struct xfs_btree_block  *rblock,
         int                     rblocklen,
         xfs_bmdr_block_t        *dblock,
         int                     dblocklen)
@@ -441,8 +441,8 @@ xfs_bmbt_to_bmdr(
         __be64                  *tpp;
 
         ASSERT(be32_to_cpu(rblock->bb_magic) == XFS_BMAP_MAGIC);
-        ASSERT(be64_to_cpu(rblock->bb_leftsib) == NULLDFSBNO);
-        ASSERT(be64_to_cpu(rblock->bb_rightsib) == NULLDFSBNO);
+        ASSERT(be64_to_cpu(rblock->bb_u.l.bb_leftsib) == NULLDFSBNO);
+        ASSERT(be64_to_cpu(rblock->bb_u.l.bb_rightsib) == NULLDFSBNO);
         ASSERT(be16_to_cpu(rblock->bb_level) > 0);
         dblock->bb_level = rblock->bb_level;
         dblock->bb_numrecs = rblock->bb_numrecs;
@@ -906,7 +906,7 @@ xfs_bmbt_maxrecs(
         int                     blocklen,
         int                     leaf)
 {
-        blocklen -= sizeof(struct xfs_btree_lblock);
+        blocklen -= XFS_BMBT_BLOCK_LEN(mp);
 
         if (leaf)
                 return blocklen / sizeof(xfs_bmbt_rec_t);
diff --git a/fs/xfs/xfs_bmap_btree.h b/fs/xfs/xfs_bmap_btree.h
index 7f001072db47..735a42418c99 100644
--- a/fs/xfs/xfs_bmap_btree.h
+++ b/fs/xfs/xfs_bmap_btree.h
@@ -22,7 +22,6 @@
 
 struct xfs_btree_cur;
 struct xfs_btree_block;
-struct xfs_btree_lblock;
 struct xfs_mount;
 struct xfs_inode;
 struct xfs_trans;
@@ -147,27 +146,29 @@ typedef struct xfs_bmbt_key {
 /* btree pointer type */
 typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
 
-/* btree block header type */
-typedef struct xfs_btree_lblock xfs_bmbt_block_t;
-
-#define XFS_BUF_TO_BMBT_BLOCK(bp)       ((xfs_bmbt_block_t *)XFS_BUF_PTR(bp))
+/*
+ * Btree block header size depends on a superblock flag.
+ *
+ * (not quite yet, but soon)
+ */
+#define XFS_BMBT_BLOCK_LEN(mp)  XFS_BTREE_LBLOCK_LEN
 
 #define XFS_BMBT_REC_ADDR(mp, block, index) \
         ((xfs_bmbt_rec_t *) \
                 ((char *)(block) + \
-                 sizeof(struct xfs_btree_lblock) + \
+                 XFS_BMBT_BLOCK_LEN(mp) + \
                  ((index) - 1) * sizeof(xfs_bmbt_rec_t)))
 
 #define XFS_BMBT_KEY_ADDR(mp, block, index) \
         ((xfs_bmbt_key_t *) \
                 ((char *)(block) + \
-                 sizeof(struct xfs_btree_lblock) + \
+                 XFS_BMBT_BLOCK_LEN(mp) + \
                  ((index) - 1) * sizeof(xfs_bmbt_key_t)))
 
 #define XFS_BMBT_PTR_ADDR(mp, block, index, maxrecs) \
         ((xfs_bmbt_ptr_t *) \
                 ((char *)(block) + \
-                 sizeof(struct xfs_btree_lblock) + \
+                 XFS_BMBT_BLOCK_LEN(mp) + \
                  (maxrecs) * sizeof(xfs_bmbt_key_t) + \
                  ((index) - 1) * sizeof(xfs_bmbt_ptr_t)))
 
@@ -198,7 +199,7 @@ typedef struct xfs_btree_lblock xfs_bmbt_block_t;
         XFS_BMBT_PTR_ADDR(mp, bb, i, xfs_bmbt_maxrecs(mp, sz, 0))
 
 #define XFS_BMAP_BROOT_SPACE_CALC(nrecs) \
-        (int)(sizeof(xfs_bmbt_block_t) + \
+        (int)(XFS_BTREE_LBLOCK_LEN + \
                ((nrecs) * (sizeof(xfs_bmbt_key_t) + sizeof(xfs_bmbt_ptr_t))))
 
 #define XFS_BMAP_BROOT_SPACE(bb) \
@@ -223,7 +224,7 @@ typedef struct xfs_btree_lblock xfs_bmbt_block_t;
  * Prototypes for xfs_bmap.c to call.
  */
 extern void xfs_bmdr_to_bmbt(struct xfs_mount *, xfs_bmdr_block_t *, int,
-                        xfs_bmbt_block_t *, int);
+                        struct xfs_btree_block *, int);
 extern void xfs_bmbt_get_all(xfs_bmbt_rec_host_t *r, xfs_bmbt_irec_t *s);
 extern xfs_filblks_t xfs_bmbt_get_blockcount(xfs_bmbt_rec_host_t *r);
 extern xfs_fsblock_t xfs_bmbt_get_startblock(xfs_bmbt_rec_host_t *r);
@@ -246,7 +247,7 @@ extern void xfs_bmbt_disk_set_all(xfs_bmbt_rec_t *r, xfs_bmbt_irec_t *s);
 extern void xfs_bmbt_disk_set_allf(xfs_bmbt_rec_t *r, xfs_fileoff_t o,
                         xfs_fsblock_t b, xfs_filblks_t c, xfs_exntst_t v);
 
-extern void xfs_bmbt_to_bmdr(struct xfs_mount *, xfs_bmbt_block_t *, int,
+extern void xfs_bmbt_to_bmdr(struct xfs_mount *, struct xfs_btree_block *, int,
                         xfs_bmdr_block_t *, int);
 
 extern int xfs_bmbt_get_maxrecs(struct xfs_btree_cur *, int level);
diff --git a/fs/xfs/xfs_btree.c b/fs/xfs/xfs_btree.c
index 72a26bb76430..7ed59267420d 100644
--- a/fs/xfs/xfs_btree.c
+++ b/fs/xfs/xfs_btree.c
@@ -53,10 +53,10 @@ const __uint32_t xfs_magics[XFS_BTNUM_MAX] = {
 };
 
 
-int                                     /* error (0 or EFSCORRUPTED) */
+STATIC int                              /* error (0 or EFSCORRUPTED) */
 xfs_btree_check_lblock(
         struct xfs_btree_cur    *cur,   /* btree cursor */
-        struct xfs_btree_lblock *block, /* btree long form block pointer */
+        struct xfs_btree_block  *block, /* btree long form block pointer */
         int                     level,  /* level of the btree block */
         struct xfs_buf          *bp)    /* buffer for block, if any */
 {
@@ -69,12 +69,14 @@ xfs_btree_check_lblock(
                 be16_to_cpu(block->bb_level) == level &&
                 be16_to_cpu(block->bb_numrecs) <=
                         cur->bc_ops->get_maxrecs(cur, level) &&
-                block->bb_leftsib &&
-                (be64_to_cpu(block->bb_leftsib) == NULLDFSBNO ||
-                 XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_leftsib))) &&
-                block->bb_rightsib &&
-                (be64_to_cpu(block->bb_rightsib) == NULLDFSBNO ||
-                 XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_rightsib)));
+                block->bb_u.l.bb_leftsib &&
+                (be64_to_cpu(block->bb_u.l.bb_leftsib) == NULLDFSBNO ||
+                 XFS_FSB_SANITY_CHECK(mp,
+                        be64_to_cpu(block->bb_u.l.bb_leftsib))) &&
+                block->bb_u.l.bb_rightsib &&
+                (be64_to_cpu(block->bb_u.l.bb_rightsib) == NULLDFSBNO ||
+                 XFS_FSB_SANITY_CHECK(mp,
+                        be64_to_cpu(block->bb_u.l.bb_rightsib)));
         if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp,
                         XFS_ERRTAG_BTREE_CHECK_LBLOCK,
                         XFS_RANDOM_BTREE_CHECK_LBLOCK))) {
@@ -90,7 +92,7 @@ xfs_btree_check_lblock(
 STATIC int                              /* error (0 or EFSCORRUPTED) */
 xfs_btree_check_sblock(
         struct xfs_btree_cur    *cur,   /* btree cursor */
-        struct xfs_btree_sblock *block, /* btree short form block pointer */
+        struct xfs_btree_block  *block, /* btree short form block pointer */
         int                     level,  /* level of the btree block */
         struct xfs_buf          *bp)    /* buffer containing block */
 {
@@ -107,12 +109,12 @@ xfs_btree_check_sblock(
                 be16_to_cpu(block->bb_level) == level &&
                 be16_to_cpu(block->bb_numrecs) <=
                         cur->bc_ops->get_maxrecs(cur, level) &&
-                (be32_to_cpu(block->bb_leftsib) == NULLAGBLOCK ||
-                 be32_to_cpu(block->bb_leftsib) < agflen) &&
-                block->bb_leftsib &&
-                (be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK ||
-                 be32_to_cpu(block->bb_rightsib) < agflen) &&
-                block->bb_rightsib;
+                (be32_to_cpu(block->bb_u.s.bb_leftsib) == NULLAGBLOCK ||
+                 be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) &&
+                block->bb_u.s.bb_leftsib &&
+                (be32_to_cpu(block->bb_u.s.bb_rightsib) == NULLAGBLOCK ||
+                 be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) &&
+                block->bb_u.s.bb_rightsib;
         if (unlikely(XFS_TEST_ERROR(!sblock_ok, cur->bc_mp,
                         XFS_ERRTAG_BTREE_CHECK_SBLOCK,
                         XFS_RANDOM_BTREE_CHECK_SBLOCK))) {
@@ -135,13 +137,10 @@ xfs_btree_check_block(
         int                     level,  /* level of the btree block */
         struct xfs_buf          *bp)    /* buffer containing block, if any */
 {
-        if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
-                return xfs_btree_check_lblock(cur,
-                                (struct xfs_btree_lblock *)block, level, bp);
-        } else {
-                return xfs_btree_check_sblock(cur,
-                                (struct xfs_btree_sblock *)block, level, bp);
-        }
+        if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
+                return xfs_btree_check_lblock(cur, block, level, bp);
+        else
+                return xfs_btree_check_sblock(cur, block, level, bp);
 }
 
 /*
@@ -326,8 +325,8 @@ xfs_btree_dup_cursor(
 static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur)
 {
         return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
-                sizeof(struct xfs_btree_lblock) :
-                sizeof(struct xfs_btree_sblock);
+                XFS_BTREE_LBLOCK_LEN :
+                XFS_BTREE_SBLOCK_LEN;
 }
 
 /*
@@ -510,7 +509,7 @@ xfs_btree_islastblock(
         xfs_btree_cur_t         *cur,   /* btree cursor */
         int                     level)  /* level to check */
 {
-        xfs_btree_block_t       *block; /* generic btree block pointer */
+        struct xfs_btree_block  *block; /* generic btree block pointer */
         xfs_buf_t               *bp;    /* buffer containing block */
 
         block = xfs_btree_get_block(cur, level, &bp);
@@ -530,7 +529,7 @@ xfs_btree_firstrec(
         xfs_btree_cur_t         *cur,   /* btree cursor */
         int                     level)  /* level to change */
 {
-        xfs_btree_block_t       *block; /* generic btree block pointer */
+        struct xfs_btree_block  *block; /* generic btree block pointer */
         xfs_buf_t               *bp;    /* buffer containing block */
 
         /*
@@ -559,7 +558,7 @@ xfs_btree_lastrec(
         xfs_btree_cur_t         *cur,   /* btree cursor */
         int                     level)  /* level to change */
 {
-        xfs_btree_block_t       *block; /* generic btree block pointer */
+        struct xfs_btree_block  *block; /* generic btree block pointer */
         xfs_buf_t               *bp;    /* buffer containing block */
 
         /*
@@ -814,7 +813,7 @@ xfs_btree_setbuf(
         int                     lev,    /* level in btree */
         xfs_buf_t               *bp)    /* new buffer to set */
 {
-        xfs_btree_block_t       *b;     /* btree block */
+        struct xfs_btree_block  *b;     /* btree block */
         xfs_buf_t               *obp;   /* old buffer pointer */
 
         obp = cur->bc_bufs[lev];
@@ -1252,20 +1251,20 @@ xfs_btree_log_block(
         int                     first;  /* first byte offset logged */
         int                     last;   /* last byte offset logged */
         static const short      soffsets[] = {  /* table of offsets (short) */
-                offsetof(struct xfs_btree_sblock, bb_magic),
-                offsetof(struct xfs_btree_sblock, bb_level),
-                offsetof(struct xfs_btree_sblock, bb_numrecs),
-                offsetof(struct xfs_btree_sblock, bb_leftsib),
-                offsetof(struct xfs_btree_sblock, bb_rightsib),
-                sizeof(struct xfs_btree_sblock)
+                offsetof(struct xfs_btree_block, bb_magic),
+                offsetof(struct xfs_btree_block, bb_level),
+                offsetof(struct xfs_btree_block, bb_numrecs),
+                offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib),
+                offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib),
+                XFS_BTREE_SBLOCK_LEN
         };
         static const short      loffsets[] = {  /* table of offsets (long) */
-                offsetof(struct xfs_btree_lblock, bb_magic),
-                offsetof(struct xfs_btree_lblock, bb_level),
-                offsetof(struct xfs_btree_lblock, bb_numrecs),
-                offsetof(struct xfs_btree_lblock, bb_leftsib),
-                offsetof(struct xfs_btree_lblock, bb_rightsib),
-                sizeof(struct xfs_btree_lblock)
+                offsetof(struct xfs_btree_block, bb_magic),
+                offsetof(struct xfs_btree_block, bb_level),
+                offsetof(struct xfs_btree_block, bb_numrecs),
+                offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib),
+                offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib),
+                XFS_BTREE_LBLOCK_LEN
         };
 
         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
@@ -3018,7 +3017,7 @@ xfs_btree_kill_iroot(
         if (index) {
                 xfs_iroot_realloc(cur->bc_private.b.ip, index,
                                   cur->bc_private.b.whichfork);
-                block = (struct xfs_btree_block *)ifp->if_broot;
+                block = ifp->if_broot;
         }
 
         be16_add_cpu(&block->bb_numrecs, index);
diff --git a/fs/xfs/xfs_btree.h b/fs/xfs/xfs_btree.h
index d6120a749060..789fffdf8b2f 100644
--- a/fs/xfs/xfs_btree.h
+++ b/fs/xfs/xfs_btree.h
@@ -39,31 +39,16 @@ extern kmem_zone_t	*xfs_btree_cur_zone;
 #define XFS_BTNUM_INO   ((xfs_btnum_t)XFS_BTNUM_INOi)
 
 /*
- * Short form header: space allocation btrees.
- */
-typedef struct xfs_btree_sblock {
-        __be32          bb_magic;       /* magic number for block type */
-        __be16          bb_level;       /* 0 is a leaf */
-        __be16          bb_numrecs;     /* current # of data records */
-        __be32          bb_leftsib;     /* left sibling block or NULLAGBLOCK */
-        __be32          bb_rightsib;    /* right sibling block or NULLAGBLOCK */
-} xfs_btree_sblock_t;
-
-/*
- * Long form header: bmap btrees.
- */
-typedef struct xfs_btree_lblock {
-        __be32          bb_magic;       /* magic number for block type */
-        __be16          bb_level;       /* 0 is a leaf */
-        __be16          bb_numrecs;     /* current # of data records */
-        __be64          bb_leftsib;     /* left sibling block or NULLDFSBNO */
-        __be64          bb_rightsib;    /* right sibling block or NULLDFSBNO */
-} xfs_btree_lblock_t;
-
-/*
- * Combined header and structure, used by common code.
+ * Generic btree header.
+ *
+ * This is a comination of the actual format used on disk for short and long
+ * format btrees.  The first three fields are shared by both format, but
+ * the pointers are different and should be used with care.
+ *
+ * To get the size of the actual short or long form headers please use
+ * the size macros below.  Never use sizeof(xfs_btree_block).
  */
-typedef struct xfs_btree_block {
+struct xfs_btree_block {
         __be32          bb_magic;       /* magic number for block type */
         __be16          bb_level;       /* 0 is a leaf */
         __be16          bb_numrecs;     /* current # of data records */
@@ -77,7 +62,11 @@ typedef struct xfs_btree_block {
                         __be64          bb_rightsib;
                 } l;                    /* long form pointers */
         } bb_u;                         /* rest */
-} xfs_btree_block_t;
+};
+
+#define XFS_BTREE_SBLOCK_LEN    16      /* size of a short form block */
+#define XFS_BTREE_LBLOCK_LEN    24      /* size of a long form block */
+
 
 /*
  * Generic key, ptr and record wrapper structures.
@@ -294,20 +283,8 @@ typedef struct xfs_btree_cur
 /*
  * Convert from buffer to btree block header.
  */
-#define XFS_BUF_TO_BLOCK(bp)    ((xfs_btree_block_t *)XFS_BUF_PTR(bp))
-#define XFS_BUF_TO_LBLOCK(bp)   ((xfs_btree_lblock_t *)XFS_BUF_PTR(bp))
-#define XFS_BUF_TO_SBLOCK(bp)   ((xfs_btree_sblock_t *)XFS_BUF_PTR(bp))
-
+#define XFS_BUF_TO_BLOCK(bp)    ((struct xfs_btree_block *)XFS_BUF_PTR(bp))
 
-/*
- * Check that long form block header is ok.
- */
-int                                     /* error (0 or EFSCORRUPTED) */
-xfs_btree_check_lblock(
-        struct xfs_btree_cur    *cur,   /* btree cursor */
-        struct xfs_btree_lblock *block, /* btree long form block pointer */
-        int                     level,  /* level of the btree block */
-        struct xfs_buf          *bp);   /* buffer containing block, if any */
 
 /*
  * Check that block header is ok.
diff --git a/fs/xfs/xfs_dinode.h b/fs/xfs/xfs_dinode.h
index 2a00fcc36d8e..d7cf392cc852 100644
--- a/fs/xfs/xfs_dinode.h
+++ b/fs/xfs/xfs_dinode.h
@@ -165,7 +165,7 @@ typedef enum xfs_dinode_fmt
  */
 #define XFS_LITINO(mp)  ((mp)->m_litino)
 #define XFS_BROOT_SIZE_ADJ      \
-        (sizeof(xfs_bmbt_block_t) - sizeof(xfs_bmdr_block_t))
+        (XFS_BTREE_LBLOCK_LEN - sizeof(xfs_bmdr_block_t))
 
 /*
  * Inode data & attribute fork sizes, per inode.
diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index 8ce72aba027f..f1d0585041b9 100644
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -126,7 +126,7 @@ xfs_growfs_data_private(
         xfs_extlen_t            agsize;
         xfs_extlen_t            tmpsize;
         xfs_alloc_rec_t         *arec;
-        xfs_btree_sblock_t      *block;
+        struct xfs_btree_block  *block;
         xfs_buf_t               *bp;
         int                     bucket;
         int                     dpct;
@@ -251,13 +251,13 @@ xfs_growfs_data_private(
                 bp = xfs_buf_get(mp->m_ddev_targp,
                         XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
                         BTOBB(mp->m_sb.sb_blocksize), 0);
-                block = XFS_BUF_TO_SBLOCK(bp);
+                block = XFS_BUF_TO_BLOCK(bp);
                 memset(block, 0, mp->m_sb.sb_blocksize);
                 block->bb_magic = cpu_to_be32(XFS_ABTB_MAGIC);
                 block->bb_level = 0;
                 block->bb_numrecs = cpu_to_be16(1);
-                block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
-                block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
+                block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
+                block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
                 arec = XFS_ALLOC_REC_ADDR(mp, block, 1);
                 arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
                 arec->ar_blockcount = cpu_to_be32(
@@ -272,13 +272,13 @@ xfs_growfs_data_private(
                 bp = xfs_buf_get(mp->m_ddev_targp,
                         XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
                         BTOBB(mp->m_sb.sb_blocksize), 0);
-                block = XFS_BUF_TO_SBLOCK(bp);
+                block = XFS_BUF_TO_BLOCK(bp);
                 memset(block, 0, mp->m_sb.sb_blocksize);
                 block->bb_magic = cpu_to_be32(XFS_ABTC_MAGIC);
                 block->bb_level = 0;
                 block->bb_numrecs = cpu_to_be16(1);
-                block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
-                block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
+                block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
+                block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
                 arec = XFS_ALLOC_REC_ADDR(mp, block, 1);
                 arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
                 arec->ar_blockcount = cpu_to_be32(
@@ -294,13 +294,13 @@ xfs_growfs_data_private(
                 bp = xfs_buf_get(mp->m_ddev_targp,
                         XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
                         BTOBB(mp->m_sb.sb_blocksize), 0);
-                block = XFS_BUF_TO_SBLOCK(bp);
+                block = XFS_BUF_TO_BLOCK(bp);
                 memset(block, 0, mp->m_sb.sb_blocksize);
                 block->bb_magic = cpu_to_be32(XFS_IBT_MAGIC);
                 block->bb_level = 0;
                 block->bb_numrecs = 0;
-                block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
-                block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
+                block->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
+                block->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
                 error = xfs_bwrite(mp, bp);
                 if (error) {
                         goto error0;
diff --git a/fs/xfs/xfs_ialloc_btree.c b/fs/xfs/xfs_ialloc_btree.c
index 46aabb3fcbf3..99f2408e8d8e 100644
--- a/fs/xfs/xfs_ialloc_btree.c
+++ b/fs/xfs/xfs_ialloc_btree.c
@@ -375,7 +375,7 @@ xfs_inobt_maxrecs(
         int                     blocklen,
         int                     leaf)
 {
-        blocklen -= sizeof(struct xfs_btree_sblock);
+        blocklen -= XFS_INOBT_BLOCK_LEN(mp);
 
         if (leaf)
                 return blocklen / sizeof(xfs_inobt_rec_t);
diff --git a/fs/xfs/xfs_ialloc_btree.h b/fs/xfs/xfs_ialloc_btree.h
index fa12c85db340..37e5dd01a577 100644
--- a/fs/xfs/xfs_ialloc_btree.h
+++ b/fs/xfs/xfs_ialloc_btree.h
@@ -24,7 +24,6 @@
 
 struct xfs_buf;
 struct xfs_btree_cur;
-struct xfs_btree_sblock;
 struct xfs_mount;
 
 /*
@@ -70,11 +69,6 @@ typedef struct xfs_inobt_key {
 /* btree pointer type */
 typedef __be32 xfs_inobt_ptr_t;
 
-/* btree block header type */
-typedef struct xfs_btree_sblock xfs_inobt_block_t;
-
-#define XFS_BUF_TO_INOBT_BLOCK(bp)      ((xfs_inobt_block_t *)XFS_BUF_PTR(bp))
-
 /*
  * Bit manipulations for ir_free.
  */
@@ -96,6 +90,13 @@ typedef	struct xfs_btree_sblock xfs_inobt_block_t;
 #define XFS_PREALLOC_BLOCKS(mp)         ((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
 
 /*
+ * Btree block header size depends on a superblock flag.
+ *
+ * (not quite yet, but soon)
+ */
+#define XFS_INOBT_BLOCK_LEN(mp) XFS_BTREE_SBLOCK_LEN
+
+/*
  * Record, key, and pointer address macros for btree blocks.
  *
  * (note that some of these may appear unused, but they are used in userspace)
@@ -103,19 +104,19 @@ typedef	struct xfs_btree_sblock xfs_inobt_block_t;
 #define XFS_INOBT_REC_ADDR(mp, block, index) \
         ((xfs_inobt_rec_t *) \
                 ((char *)(block) + \
-                 sizeof(struct xfs_btree_sblock) + \
+                 XFS_INOBT_BLOCK_LEN(mp) + \
                  (((index) - 1) * sizeof(xfs_inobt_rec_t))))
 
 #define XFS_INOBT_KEY_ADDR(mp, block, index) \
         ((xfs_inobt_key_t *) \
                 ((char *)(block) + \
-                 sizeof(struct xfs_btree_sblock) + \
+                 XFS_INOBT_BLOCK_LEN(mp) + \
                  ((index) - 1) * sizeof(xfs_inobt_key_t)))
 
 #define XFS_INOBT_PTR_ADDR(mp, block, index, maxrecs) \
         ((xfs_inobt_ptr_t *) \
                 ((char *)(block) + \
-                 sizeof(struct xfs_btree_sblock) + \
+                 XFS_INOBT_BLOCK_LEN(mp) + \
                  (maxrecs) * sizeof(xfs_inobt_key_t) + \
                  ((index) - 1) * sizeof(xfs_inobt_ptr_t)))
 
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 7b4f13c710d6..bc33762abc49 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -2352,7 +2352,7 @@ xfs_iroot_realloc(
         struct xfs_mount        *mp = ip->i_mount;
         int                     cur_max;
         xfs_ifork_t             *ifp;
-        xfs_bmbt_block_t        *new_broot;
+        struct xfs_btree_block  *new_broot;
         int                     new_max;
         size_t                  new_size;
         char                    *np;
@@ -2373,8 +2373,7 @@ xfs_iroot_realloc(
                  */
                 if (ifp->if_broot_bytes == 0) {
                         new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(rec_diff);
-                        ifp->if_broot = (xfs_bmbt_block_t*)kmem_alloc(new_size,
-                                                                     KM_SLEEP);
+                        ifp->if_broot = kmem_alloc(new_size, KM_SLEEP);
                         ifp->if_broot_bytes = (int)new_size;
                         return;
                 }
@@ -2388,9 +2387,7 @@ xfs_iroot_realloc(
                 cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
                 new_max = cur_max + rec_diff;
                 new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(new_max);
-                ifp->if_broot = (xfs_bmbt_block_t *)
-                  kmem_realloc(ifp->if_broot,
-                                new_size,
+                ifp->if_broot = kmem_realloc(ifp->if_broot, new_size,
                                 (size_t)XFS_BMAP_BROOT_SPACE_CALC(cur_max), /* old size */
                                 KM_SLEEP);
                 op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
@@ -2418,11 +2415,11 @@ xfs_iroot_realloc(
         else
                 new_size = 0;
         if (new_size > 0) {
-                new_broot = (xfs_bmbt_block_t *)kmem_alloc(new_size, KM_SLEEP);
+                new_broot = kmem_alloc(new_size, KM_SLEEP);
                 /*
                  * First copy over the btree block header.
                  */
-                memcpy(new_broot, ifp->if_broot, sizeof(xfs_bmbt_block_t));
+                memcpy(new_broot, ifp->if_broot, XFS_BTREE_LBLOCK_LEN);
         } else {
                 new_broot = NULL;
                 ifp->if_flags &= ~XFS_IFBROOT;
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 55d50b888b68..6fd20fc179a4 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -63,7 +63,7 @@ typedef struct xfs_ext_irec {
 typedef struct xfs_ifork {
         int                     if_bytes;       /* bytes in if_u1 */
         int                     if_real_bytes;  /* bytes allocated in if_u1 */
-        xfs_bmbt_block_t        *if_broot;      /* file's incore btree root */
+        struct xfs_btree_block  *if_broot;      /* file's incore btree root */
         short                   if_broot_bytes; /* bytes allocated for root */
         unsigned char           if_flags;       /* per-fork flags */
         unsigned char           if_ext_max;     /* max # of extent records */
@@ -213,7 +213,6 @@ struct ktrace;
 struct xfs_buf;
 struct xfs_bmap_free;
 struct xfs_bmbt_irec;
-struct xfs_bmbt_block;
 struct xfs_inode_log_item;
 struct xfs_mount;
 struct xfs_trans;
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 23c3a782a9e7..199c8ea36474 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -2452,8 +2452,8 @@ xlog_recover_do_inode_trans(
                 break;
 
         case XFS_ILOG_DBROOT:
-                xfs_bmbt_to_bmdr(mp, (xfs_bmbt_block_t *)src, len,
-                                 &(dip->di_u.di_bmbt),
+                xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src, len,
+                                 &dip->di_u.di_bmbt,
                                  XFS_DFORK_DSIZE(dip, mp));
                 break;
 
@@ -2490,8 +2490,8 @@ xlog_recover_do_inode_trans(
 
                 case XFS_ILOG_ABROOT:
                         dest = XFS_DFORK_APTR(dip);
-                        xfs_bmbt_to_bmdr(mp, (xfs_bmbt_block_t *)src, len,
-                                         (xfs_bmdr_block_t*)dest,
+                        xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src,
+                                         len, (xfs_bmdr_block_t*)dest,
                                          XFS_DFORK_ASIZE(dip, mp));
                         break;