contrib/vhost-user-blk: fix the compilation issue

Signed-off-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <1547615970-23545-2-git-send-email-changpeng.liu@intel.com>
[PMD: this patch was first (incorrectly) introduced as a56de056]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190212140621.17009-3-philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>

contrib/vhost-user-blk/vhost-user-blk.c

@@ -20,6 +20,10 @@
 #include "contrib/libvhost-user/libvhost-user-glib.h"
 #include "contrib/libvhost-user/libvhost-user.h"
 
+#if defined(__linux__)
+#include <linux/fs.h>
+#include <sys/ioctl.h>
+#endif
 
 struct virtio_blk_inhdr {
     unsigned char status;
@@ -521,7 +525,7 @@ vub_get_blocksize(int fd)
 
 #if defined(__linux__) && defined(BLKSSZGET)
     if (ioctl(fd, BLKSSZGET, &blocksize) == 0) {
-        return blocklen;
+        return blocksize;
     }
 #endif