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, 1 insertions, 0 deletions

diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
index 0dce969d6cad..faca44997099 100644
--- a/fs/xfs/Makefile
+++ b/fs/xfs/Makefile
@@ -98,6 +98,7 @@ xfs-y				+= $(addprefix $(XFS_LINUX)/, \
                                    kmem.o \
                                    xfs_aops.o \
                                    xfs_buf.o \
+                                   xfs_discard.o \
                                    xfs_export.o \
                                    xfs_file.o \
                                    xfs_fs_subr.o \