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, 3 insertions, 7 deletions

diff --git a/fs/xfs/xfs_alloc.c b/fs/xfs/xfs_alloc.c
index fa8723f5870a..f3227984a9bf 100644
--- a/fs/xfs/xfs_alloc.c
+++ b/fs/xfs/xfs_alloc.c
@@ -41,10 +41,6 @@
 #define XFSA_FIXUP_BNO_OK       1
 #define XFSA_FIXUP_CNT_OK       2
 
-static int
-xfs_alloc_busy_search(struct xfs_mount *mp, xfs_agnumber_t agno,
-                    xfs_agblock_t bno, xfs_extlen_t len);
-
 /*
  * Prototypes for per-ag allocation routines
  */
@@ -94,7 +90,7 @@ xfs_alloc_lookup_ge(
  * Lookup the first record less than or equal to [bno, len]
  * in the btree given by cur.
  */
-STATIC int                              /* error */
+int                                     /* error */
 xfs_alloc_lookup_le(
         struct xfs_btree_cur    *cur,   /* btree cursor */
         xfs_agblock_t           bno,    /* starting block of extent */
@@ -127,7 +123,7 @@ xfs_alloc_update(
 /*
  * Get the data from the pointed-to record.
  */
-STATIC int                              /* error */
+int                                     /* error */
 xfs_alloc_get_rec(
         struct xfs_btree_cur    *cur,   /* btree cursor */
         xfs_agblock_t           *bno,   /* output: starting block of extent */
@@ -2615,7 +2611,7 @@ restart:
  * will require a synchronous transaction, but it can still be
  * used to distinguish between a partial or exact match.
  */
-static int
+int
 xfs_alloc_busy_search(
         struct xfs_mount        *mp,
         xfs_agnumber_t          agno,