diff --git a/linux-user/ioctls.h b/linux-user/ioctls.h
index 1830de96e1..bc19448042 100644
--- a/linux-user/ioctls.h
+++ b/linux-user/ioctls.h
@@ -112,6 +112,8 @@
      IOCTL(BLKZEROOUT, IOC_W, MK_PTR(MK_ARRAY(TYPE_ULONGLONG, 2)))
 #endif
 
+     IOCTL(FDFLUSH, 0, TYPE_NULL)
+
 #ifdef FIBMAP
      IOCTL(FIBMAP, IOC_W | IOC_R, MK_PTR(TYPE_LONG))
 #endif
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 6928f654ce..e2af3c1494 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -89,6 +89,7 @@
 #include <linux/kd.h>
 #include <linux/mtio.h>
 #include <linux/fs.h>
+#include <linux/fd.h>
 #if defined(CONFIG_FIEMAP)
 #include <linux/fiemap.h>
 #endif
diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index 498223b777..917202a203 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -888,6 +888,10 @@ struct target_pollfd {
 #define TARGET_BLKROTATIONAL TARGET_IO(0x12, 126)
 #define TARGET_BLKZEROOUT TARGET_IO(0x12, 127)
 
+/* From <linux/fd.h> */
+
+#define TARGET_FDFLUSH        TARGET_IO(2, 0x4b)
+
 #define TARGET_FIBMAP     TARGET_IO(0x00,1)  /* bmap access */
 #define TARGET_FIGETBSZ   TARGET_IO(0x00,2)  /* get the block size used for bmap */