fuse: add simple background helper
Create a helper named fuse_simple_background() that is similar to
fuse_simple_request(). Unlike the latter, it returns immediately and calls
the supplied 'end' callback when the reply is received.
The supplied 'args' pointer is stored in 'fuse_req' which allows the
callback to interpret the output arguments decoded from the reply.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 29723e1..a52a738 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -626,6 +626,51 @@ bool fuse_request_queue_background(struct fuse_conn *fc, struct fuse_req *req)
return queued;
}
+static void fuse_simple_end(struct fuse_conn *fc, struct fuse_req *req)
+{
+ struct fuse_args *args = req->args;
+ int err = req->out.h.error;
+
+ if (!err && args->out_argvar) {
+ BUG_ON(args->out_numargs == 0);
+ args->out_args[args->out_numargs - 1].size =
+ req->out.args[args->out_numargs - 1].size;
+ }
+ req->args->end(fc, req->args, req->out.h.error);
+}
+
+int fuse_simple_background(struct fuse_conn *fc, struct fuse_args *args,
+ gfp_t gfp_flags)
+{
+ struct fuse_req *req;
+
+ if (args->force) {
+ WARN_ON(!args->nocreds);
+ req = __fuse_request_alloc(0, gfp_flags);
+ if (!req)
+ return -ENOMEM;
+ __set_bit(FR_BACKGROUND, &req->flags);
+ } else {
+ WARN_ON(args->nocreds);
+ req = __fuse_get_req(fc, 0, true);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+ }
+
+ fuse_args_to_req(req, args);
+
+ req->args = args;
+ req->end = fuse_simple_end;
+
+ if (!fuse_request_queue_background(fc, req)) {
+ fuse_put_request(fc, req);
+ return -ENOTCONN;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(fuse_simple_background);
+
void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req)
{
WARN_ON(!req->end);
