sep: Convert sep_lock_user_pages() to get_user_pages_fast()

CC: Mark Allyn <mark.a.allyn@intel.com>
CC: Jayant Mangalampalli <jayant.mangalampalli@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/sep/sep_main.c

@@ -1263,13 +1263,8 @@ static int sep_lock_user_pages(struct sep_device *sep,
 	}
 
 	/* Convert the application virtual address into a set of physical */
-	down_read(&current->mm->mmap_sem);
-	result = get_user_pages(current, current->mm, app_virt_addr,
-		num_pages,
-		((in_out_flag == SEP_DRIVER_IN_FLAG) ? 0 : 1),
-		0, page_array, NULL);
-
-	up_read(&current->mm->mmap_sem);
+	result = get_user_pages_fast(app_virt_addr, num_pages,
+		((in_out_flag == SEP_DRIVER_IN_FLAG) ? 0 : 1), page_array);
 
 	/* Check the number of pages locked - if not all then exit with error */
 	if (result != num_pages) {