diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 1dafe07..a0a94a3 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1726,12 +1726,7 @@
 
 	mutex_lock(&inode->i_mutex);
 
-	err = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
-	if (err) {
-		mutex_unlock(&inode->i_mutex);
-		goto out;
-	}
-	count = ocount;
+	count = ocount = iov_length(iov, nr_segs);
 
 	current->backing_dev_info = inode->i_mapping->backing_dev_info;
 	err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));