1 files changed, 3 insertions, 0 deletions

diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index 9bd086c1a4d5..f26051f44681 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -6,6 +6,7 @@
 #include <linux/elevator.h>
 #include <linux/fd.h>
 #include <linux/hdreg.h>
+#include <linux/slab.h>
 #include <linux/syscalls.h>
 #include <linux/smp_lock.h>
 #include <linux/types.h>
@@ -747,6 +748,8 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
                 return compat_put_uint(arg, bdev_io_opt(bdev));
         case BLKALIGNOFF:
                 return compat_put_int(arg, bdev_alignment_offset(bdev));
+        case BLKDISCARDZEROES:
+                return compat_put_uint(arg, bdev_discard_zeroes_data(bdev));
         case BLKFLSBUF:
         case BLKROSET:
         case BLKDISCARD: