Commit 5e3c3a7e authored by Kevin Vigor's avatar Kevin Vigor Committed by Jens Axboe
Browse files

nbd: clear DISCONNECT_REQUESTED flag once disconnection occurs. 



When a userspace client requests a NBD device be disconnected, the
DISCONNECT_REQUESTED flag is set. While this flag is set, the driver
will not inform userspace when a connection is closed.

Unfortunately the flag was never cleared, so once a disconnect was
requested the driver would thereafter never tell userspace about a
closed connection. Thus when connections failed due to timeout, no
attempt to reconnect was made and eventually the device would fail.

Fix by clearing the DISCONNECT_REQUESTED flag (and setting the
DISCONNECTED flag) once all connections are closed.

Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarKevin Vigor <kvigor@fb.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 2ab74cd2

drivers/block/nbd.c

+15 −6
Original line number Original line Diff line number Diff line
@@ -216,7 +216,15 @@ static void nbd_mark_nsock_dead(struct nbd_device *nbd, struct nbd_sock *nsock, 
	}

	}

	if (!nsock->dead) {

	if (!nsock->dead) {

		kernel_sock_shutdown(nsock->sock, SHUT_RDWR);

		kernel_sock_shutdown(nsock->sock, SHUT_RDWR);

		atomic_dec(&nbd->config->live_connections);

		if (atomic_dec_return(&nbd->config->live_connections) == 0) {

			if (test_and_clear_bit(NBD_DISCONNECT_REQUESTED,

					       &nbd->config->runtime_flags)) {

				set_bit(NBD_DISCONNECTED,

					&nbd->config->runtime_flags);

				dev_info(nbd_to_dev(nbd),

					"Disconnected due to user request.\n");

			}

		}

	}

	}

	nsock->dead = true;

	nsock->dead = true;

	nsock->pending = NULL;

	nsock->pending = NULL;
@@ -310,7 +318,9 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req, 




	if (config->num_connections > 1) {

	if (config->num_connections > 1) {

		dev_err_ratelimited(nbd_to_dev(nbd),

		dev_err_ratelimited(nbd_to_dev(nbd),

				    "Connection timed out, retrying\n");

				    "Connection timed out, retrying (%d/%d alive)\n",

				    atomic_read(&config->live_connections),

				    config->num_connections);

		/*

		/*

		 * Hooray we have more connections, requeue this IO, the submit

		 * Hooray we have more connections, requeue this IO, the submit

		 * path will put it on a real connection.

		 * path will put it on a real connection.
@@ -733,10 +743,9 @@ static int wait_for_reconnect(struct nbd_device *nbd) 
		return 0;

		return 0;

	if (test_bit(NBD_DISCONNECTED, &config->runtime_flags))

	if (test_bit(NBD_DISCONNECTED, &config->runtime_flags))

		return 0;

		return 0;

	wait_event_timeout(config->conn_wait,

	return wait_event_timeout(config->conn_wait,

			   atomic_read(&config->live_connections),

				  atomic_read(&config->live_connections) > 0,

			   config->dead_conn_timeout);

				  config->dead_conn_timeout) > 0;

	return atomic_read(&config->live_connections);

}

}





static int nbd_handle_cmd(struct nbd_cmd *cmd, int index)

static int nbd_handle_cmd(struct nbd_cmd *cmd, int index)

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