diff --git a/fs/block_dev.c b/fs/block_dev.c
index 7eeb0635338b..37967bcea05c 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1648,7 +1648,7 @@ ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
 }
 EXPORT_SYMBOL_GPL(blkdev_aio_write);
 
-int blkdev_mmap(struct file *file, struct vm_area_struct *vma)
+static int blkdev_mmap(struct file *file, struct vm_area_struct *vma)
 {
 	int ret;
 	struct block_device *bdev = I_BDEV(file->f_mapping->host);