[XFS] split up xfs_btree_init_cursor

xfs_btree_init_cursor contains close to little shared code for the
different btrees and will get even more non-common code in the future.
Split it up into one routine per btree type.

Because xfs_btree_dup_cursor needs to call the init routine for a generic
btree cursor add a new btree operation vector that contains a dup_cursor
method that initializes a new cursor based on an existing one.

The btree operations vector is based on an idea and code from Dave Chinner
and will grow more entries later during this series.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32176a

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>

1 files changed, 4 insertions, 0 deletions

diff --git a/fs/xfs/xfs_bmap_btree.h b/fs/xfs/xfs_bmap_btree.h
index cd0d4b4bb816..4f12fff54975 100644
--- a/fs/xfs/xfs_bmap_btree.h
+++ b/fs/xfs/xfs_bmap_btree.h
@@ -24,6 +24,7 @@ struct xfs_btree_cur;
 struct xfs_btree_lblock;
 struct xfs_mount;
 struct xfs_inode;
+struct xfs_trans;
 
 /*
  * Bmap root header, on-disk form only.
@@ -300,6 +301,9 @@ extern void xfs_bmbt_to_bmdr(xfs_bmbt_block_t *, int, xfs_bmdr_block_t *, int);
 extern int xfs_bmbt_update(struct xfs_btree_cur *, xfs_fileoff_t,
                                 xfs_fsblock_t, xfs_filblks_t, xfs_exntst_t);
 
+extern struct xfs_btree_cur *xfs_bmbt_init_cursor(struct xfs_mount *,
+                struct xfs_trans *, struct xfs_inode *, int);
+
 #endif  /* __KERNEL__ */
 
 #endif  /* __XFS_BMAP_BTREE_H__ */