[XFS] make btree root in inode support generic
The bmap btree is rooted in the inode and not in a disk block. Make the
support for this feature more generic by adding a btree flag to for this
feature instead of relying on the XFS_BTNUM_BMAP btnum check.
Also clean up xfs_btree_get_block where this new flag is used.
Based upon a patch from Dave Chinner.
SGI-PV: 985583
SGI-Modid: xfs-linux-melb:xfs-kern:32180a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Bill O'Donnell <billodo@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
diff --git a/fs/xfs/xfs_btree.c b/fs/xfs/xfs_btree.c
index 074f7f6..57e858f 100644
--- a/fs/xfs/xfs_btree.c
+++ b/fs/xfs/xfs_btree.c
@@ -422,32 +422,39 @@
}
/*
- * Retrieve the block pointer from the cursor at the given level.
- * This may be a bmap btree root or from a buffer.
+ * Get a the root block which is stored in the inode.
+ *
+ * For now this btree implementation assumes the btree root is always
+ * stored in the if_broot field of an inode fork.
*/
-STATIC xfs_btree_block_t * /* generic btree block pointer */
-xfs_btree_get_block(
- xfs_btree_cur_t *cur, /* btree cursor */
- int level, /* level in btree */
- xfs_buf_t **bpp) /* buffer containing the block */
+STATIC struct xfs_btree_block *
+xfs_btree_get_iroot(
+ struct xfs_btree_cur *cur)
{
- xfs_btree_block_t *block; /* return value */
- xfs_buf_t *bp; /* return buffer */
- xfs_ifork_t *ifp; /* inode fork pointer */
- int whichfork; /* data or attr fork */
+ struct xfs_ifork *ifp;
- if (cur->bc_btnum == XFS_BTNUM_BMAP && level == cur->bc_nlevels - 1) {
- whichfork = cur->bc_private.b.whichfork;
- ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, whichfork);
- block = (xfs_btree_block_t *)ifp->if_broot;
- bp = NULL;
- } else {
- bp = cur->bc_bufs[level];
- block = XFS_BUF_TO_BLOCK(bp);
+ ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork);
+ return (struct xfs_btree_block *)ifp->if_broot;
+}
+
+/*
+ * Retrieve the block pointer from the cursor at the given level.
+ * This may be an inode btree root or from a buffer.
+ */
+STATIC struct xfs_btree_block * /* generic btree block pointer */
+xfs_btree_get_block(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ int level, /* level in btree */
+ struct xfs_buf **bpp) /* buffer containing the block */
+{
+ if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
+ (level == cur->bc_nlevels - 1)) {
+ *bpp = NULL;
+ return xfs_btree_get_iroot(cur);
}
- ASSERT(block != NULL);
- *bpp = bp;
- return block;
+
+ *bpp = cur->bc_bufs[level];
+ return XFS_BUF_TO_BLOCK(*bpp);
}
/*