xfs: use XFS_BMAP_BMDR_SPACE vs. XFS_BROOT_SIZE_ADJ

XFS_BROOT_SIZE_ADJ is an undocumented macro which accounts for
the difference in size between the on-disk and in-core btree
root.  It's much clearer to just use the newly-added
XFS_BMAP_BMDR_SPACE macro which gives us the on-disk size
directly.

In one case, we must test that the if_broot exists before
applying the macro, however.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

2 files changed, 7 insertions, 10 deletions

diff --git a/fs/xfs/xfs_dinode.h b/fs/xfs/xfs_dinode.h
index f7a0e95d197a..07d735a80a0f 100644
--- a/fs/xfs/xfs_dinode.h
+++ b/fs/xfs/xfs_dinode.h
@@ -132,9 +132,6 @@ typedef enum xfs_dinode_fmt {
 #define XFS_LITINO(mp, version) \
         ((int)(((mp)->m_sb.sb_inodesize) - xfs_dinode_size(version)))
 
-#define XFS_BROOT_SIZE_ADJ(ip) \
-        (XFS_BMBT_BLOCK_LEN((ip)->i_mount) - sizeof(xfs_bmdr_block_t))
-
 /*
  * Inode data & attribute fork sizes, per inode.
  */
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 9ecfe1e559fc..b78481f99d9d 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -2156,8 +2156,8 @@ xfs_iroot_realloc(
                 np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
                                                      (int)new_size);
                 ifp->if_broot_bytes = (int)new_size;
-                ASSERT(ifp->if_broot_bytes <=
-                        XFS_IFORK_SIZE(ip, whichfork) + XFS_BROOT_SIZE_ADJ(ip));
+                ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
+                        XFS_IFORK_SIZE(ip, whichfork));
                 memmove(np, op, cur_max * (uint)sizeof(xfs_dfsbno_t));
                 return;
         }
@@ -2210,8 +2210,9 @@ xfs_iroot_realloc(
         kmem_free(ifp->if_broot);
         ifp->if_broot = new_broot;
         ifp->if_broot_bytes = (int)new_size;
-        ASSERT(ifp->if_broot_bytes <=
-                XFS_IFORK_SIZE(ip, whichfork) + XFS_BROOT_SIZE_ADJ(ip));
+        if (ifp->if_broot)
+                ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
+                        XFS_IFORK_SIZE(ip, whichfork));
         return;
 }
 
@@ -2522,9 +2523,8 @@ xfs_iflush_fork(
                 if ((iip->ili_fields & brootflag[whichfork]) &&
                     (ifp->if_broot_bytes > 0)) {
                         ASSERT(ifp->if_broot != NULL);
-                        ASSERT(ifp->if_broot_bytes <=
-                               (XFS_IFORK_SIZE(ip, whichfork) +
-                                XFS_BROOT_SIZE_ADJ(ip)));
+                        ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
+                                XFS_IFORK_SIZE(ip, whichfork));
                         xfs_bmbt_to_bmdr(mp, ifp->if_broot, ifp->if_broot_bytes,
                                 (xfs_bmdr_block_t *)cp,
                                 XFS_DFORK_SIZE(dip, mp, whichfork));