xfs: add FITRIM support

Allow manual discards from userspace using the FITRIM ioctl.  This is not
intended to be run during normal workloads, as the freepsace btree walks
can cause large performance degradation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>

1 files changed, 20 insertions, 5 deletions

diff --git a/fs/xfs/xfs_alloc.h b/fs/xfs/xfs_alloc.h
index 895009a97271..0ab56b32c7eb 100644
--- a/fs/xfs/xfs_alloc.h
+++ b/fs/xfs/xfs_alloc.h
@@ -19,6 +19,7 @@
 #define __XFS_ALLOC_H__
 
 struct xfs_buf;
+struct xfs_btree_cur;
 struct xfs_mount;
 struct xfs_perag;
 struct xfs_trans;
@@ -118,16 +119,16 @@ xfs_alloc_longest_free_extent(struct xfs_mount *mp,
                 struct xfs_perag *pag);
 
 #ifdef __KERNEL__
-
 void
-xfs_alloc_busy_insert(xfs_trans_t *tp,
-                xfs_agnumber_t agno,
-                xfs_agblock_t bno,
-                xfs_extlen_t len);
+xfs_alloc_busy_insert(struct xfs_trans *tp, xfs_agnumber_t agno,
+        xfs_agblock_t bno, xfs_extlen_t len);
 
 void
 xfs_alloc_busy_clear(struct xfs_mount *mp, struct xfs_busy_extent *busyp);
 
+int
+xfs_alloc_busy_search(struct xfs_mount *mp, xfs_agnumber_t agno,
+        xfs_agblock_t bno, xfs_extlen_t len);
 #endif  /* __KERNEL__ */
 
 /*
@@ -205,4 +206,18 @@ xfs_free_extent(
         xfs_fsblock_t   bno,    /* starting block number of extent */
         xfs_extlen_t    len);   /* length of extent */
 
+int                                     /* error */
+xfs_alloc_lookup_le(
+        struct xfs_btree_cur    *cur,   /* btree cursor */
+        xfs_agblock_t           bno,    /* starting block of extent */
+        xfs_extlen_t            len,    /* length of extent */
+        int                     *stat); /* success/failure */
+
+int                                     /* error */
+xfs_alloc_get_rec(
+        struct xfs_btree_cur    *cur,   /* btree cursor */
+        xfs_agblock_t           *bno,   /* output: starting block of extent */
+        xfs_extlen_t            *len,   /* output: length of extent */
+        int                     *stat); /* output: success/failure */
+
 #endif  /* __XFS_ALLOC_H__ */