fuse: export fuse_len_args()

virtio-fs will need to query the length of fuse_arg lists.  Make the symbol
visible.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

fs/fuse/dev.c

@@ -177,7 +177,7 @@ static void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
 }
 EXPORT_SYMBOL_GPL(fuse_put_request);
 
-static unsigned len_args(unsigned numargs, struct fuse_arg *args)
+unsigned int fuse_len_args(unsigned int numargs, struct fuse_arg *args)
 {
 	unsigned nbytes = 0;
 	unsigned i;
@@ -187,6 +187,7 @@ static unsigned len_args(unsigned numargs, struct fuse_arg *args)
 
 	return nbytes;
 }
+EXPORT_SYMBOL_GPL(fuse_len_args);
 
 static u64 fuse_get_unique(struct fuse_iqueue *fiq)
 {
@@ -202,8 +203,8 @@ static unsigned int fuse_req_hash(u64 unique)
 static void queue_request(struct fuse_iqueue *fiq, struct fuse_req *req)
 {
 	req->in.h.len = sizeof(struct fuse_in_header) +
-		len_args(req->args->in_numargs,
-			 (struct fuse_arg *) req->args->in_args);
+		fuse_len_args(req->args->in_numargs,
+			      (struct fuse_arg *) req->args->in_args);
 	list_add_tail(&req->list, &fiq->pending);
 	wake_up(&fiq->waitq);
 	kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
@@ -1779,7 +1780,7 @@ static int copy_out_args(struct fuse_copy_state *cs, struct fuse_args *args,
 {
 	unsigned reqsize = sizeof(struct fuse_out_header);
 
-	reqsize += len_args(args->out_numargs, args->out_args);
+	reqsize += fuse_len_args(args->out_numargs, args->out_args);
 
 	if (reqsize < nbytes || (reqsize > nbytes && !args->out_argvar))
 		return -EINVAL;

fs/fuse/fuse_i.h

@@ -971,4 +971,9 @@ int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type);
 /* readdir.c */
 int fuse_readdir(struct file *file, struct dir_context *ctx);
 
+/**
+ * Return the number of bytes in an arguments list
+ */
+unsigned int fuse_len_args(unsigned int numargs, struct fuse_arg *args);
+
 #endif /* _FS_FUSE_I_H */