xfs: factor out code to find the longest free extent in the AG

Signed-off-by: Dave Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/xfs/xfs_alloc.h b/fs/xfs/xfs_alloc.h
index 588172796f7b..e704caee10df 100644
--- a/fs/xfs/xfs_alloc.h
+++ b/fs/xfs/xfs_alloc.h
@@ -100,6 +100,12 @@ typedef struct xfs_alloc_arg {
 #define XFS_ALLOC_USERDATA              1       /* allocation is for user data*/
 #define XFS_ALLOC_INITIAL_USER_DATA     2       /* special case start of file */
 
+/*
+ * Find the length of the longest extent in an AG.
+ */
+xfs_extlen_t
+xfs_alloc_longest_free_extent(struct xfs_mount *mp,
+                struct xfs_perag *pag);
 
 #ifdef __KERNEL__