fuse: add flag fc->initialized

Existing flag fc->blocked is used to suspend request allocation both in case
of many background request submitted and period of time before init_reply
arrives from userspace. Next patch will skip blocking allocations of
synchronous request (disregarding fc->blocked). This is mostly OK, but
we still need to suspend allocations if init_reply is not arrived yet. The
patch introduces flag fc->initialized which will serve this purpose.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

fs/fuse/cuse.c

@@ -505,6 +505,7 @@ static int cuse_channel_open(struct inode *inode, struct file *file)
 
 	cc->fc.connected = 1;
 	cc->fc.blocked = 0;
+	cc->fc.initialized = 1;
 	rc = cuse_send_init(cc);
 	if (rc) {
 		fuse_conn_put(&cc->fc);

fs/fuse/dev.c

@@ -2087,6 +2087,7 @@ void fuse_abort_conn(struct fuse_conn *fc)
 	if (fc->connected) {
 		fc->connected = 0;
 		fc->blocked = 0;
+		fc->initialized = 1;
 		end_io_requests(fc);
 		end_queued_requests(fc);
 		end_polls(fc);

fs/fuse/fuse_i.h

@@ -417,6 +417,10 @@ struct fuse_conn {
 	/** Batching of FORGET requests (positive indicates FORGET batch) */
 	int forget_batch;
 
+	/** Flag indicating that INIT reply has been received. Allocating
+	 * any fuse request will be suspended until the flag is set */
+	int initialized;
+
 	/** Flag indicating if connection is blocked.  This will be
 	    the case before the INIT reply is received, and if there
 	    are too many outstading backgrounds requests */

fs/fuse/inode.c

@@ -363,6 +363,7 @@ void fuse_conn_kill(struct fuse_conn *fc)
 	spin_lock(&fc->lock);
 	fc->connected = 0;
 	fc->blocked = 0;
+	fc->initialized = 1;
 	spin_unlock(&fc->lock);
 	/* Flush all readers on this fs */
 	kill_fasync(&fc->fasync, SIGIO, POLL_IN);
@@ -583,6 +584,7 @@ void fuse_conn_init(struct fuse_conn *fc)
 	fc->polled_files = RB_ROOT;
 	fc->reqctr = 0;
 	fc->blocked = 1;
+	fc->initialized = 0;
 	fc->attr_version = 1;
 	get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
 }
@@ -882,6 +884,7 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
 		fc->conn_init = 1;
 	}
 	fc->blocked = 0;
+	fc->initialized = 1;
 	wake_up_all(&fc->blocked_waitq);
 }