diff options
Diffstat (limited to 'drivers/block/nbd.c')
| -rw-r--r-- | drivers/block/nbd.c | 63 |
1 files changed, 59 insertions, 4 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 71e98cb78c95..c5f866bcfea6 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -77,9 +77,12 @@ struct link_dead_args { struct nbd_config { u32 flags; unsigned long runtime_flags; + u64 dead_conn_timeout; struct nbd_sock **socks; int num_connections; + atomic_t live_connections; + wait_queue_head_t conn_wait; atomic_t recv_threads; wait_queue_head_t recv_wq; @@ -178,8 +181,10 @@ static void nbd_mark_nsock_dead(struct nbd_device *nbd, struct nbd_sock *nsock, queue_work(system_wq, &args->work); } } - if (!nsock->dead) + if (!nsock->dead) { kernel_sock_shutdown(nsock->sock, SHUT_RDWR); + atomic_dec(&nbd->config->live_connections); + } nsock->dead = true; nsock->pending = NULL; nsock->sent = 0; @@ -257,6 +262,14 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req, return BLK_EH_HANDLED; } + /* If we are waiting on our dead timer then we could get timeout + * callbacks for our request. For this we just want to reset the timer + * and let the queue side take care of everything. + */ + if (!completion_done(&cmd->send_complete)) { + nbd_config_put(nbd); + return BLK_EH_RESET_TIMER; + } config = nbd->config; if (config->num_connections > 1) { @@ -665,6 +678,19 @@ static int find_fallback(struct nbd_device *nbd, int index) return new_index; } +static int wait_for_reconnect(struct nbd_device *nbd) +{ + struct nbd_config *config = nbd->config; + if (!config->dead_conn_timeout) + return 0; + if (test_bit(NBD_DISCONNECTED, &config->runtime_flags)) + return 0; + wait_event_interruptible_timeout(config->conn_wait, + atomic_read(&config->live_connections), + config->dead_conn_timeout); + return atomic_read(&config->live_connections); +} + static int nbd_handle_cmd(struct nbd_cmd *cmd, int index) { struct request *req = blk_mq_rq_from_pdu(cmd); @@ -691,12 +717,24 @@ again: nsock = config->socks[index]; mutex_lock(&nsock->tx_lock); if (nsock->dead) { + int old_index = index; index = find_fallback(nbd, index); + mutex_unlock(&nsock->tx_lock); if (index < 0) { - ret = -EIO; - goto out; + if (wait_for_reconnect(nbd)) { + index = old_index; + goto again; + } + /* All the sockets should already be down at this point, + * we just want to make sure that DISCONNECTED is set so + * any requests that come in that were queue'ed waiting + * for the reconnect timer don't trigger the timer again + * and instead just error out. + */ + sock_shutdown(nbd); + nbd_config_put(nbd); + return -EIO; } - mutex_unlock(&nsock->tx_lock); goto again; } @@ -809,6 +847,7 @@ static int nbd_add_socket(struct nbd_device *nbd, unsigned long arg, nsock->sent = 0; nsock->cookie = 0; socks[config->num_connections++] = nsock; + atomic_inc(&config->live_connections); return 0; } @@ -860,6 +899,9 @@ static int nbd_reconnect_socket(struct nbd_device *nbd, unsigned long arg) * need to queue_work outside of the tx_mutex. */ queue_work(recv_workqueue, &args->work); + + atomic_inc(&config->live_connections); + wake_up(&config->conn_wait); return 0; } sockfd_put(sock); @@ -1137,7 +1179,9 @@ static struct nbd_config *nbd_alloc_config(void) return NULL; atomic_set(&config->recv_threads, 0); init_waitqueue_head(&config->recv_wq); + init_waitqueue_head(&config->conn_wait); config->blksize = 1024; + atomic_set(&config->live_connections, 0); try_module_get(THIS_MODULE); return config; } @@ -1448,6 +1492,7 @@ static struct nla_policy nbd_attr_policy[NBD_ATTR_MAX + 1] = { [NBD_ATTR_SERVER_FLAGS] = { .type = NLA_U64 }, [NBD_ATTR_CLIENT_FLAGS] = { .type = NLA_U64 }, [NBD_ATTR_SOCKETS] = { .type = NLA_NESTED}, + [NBD_ATTR_DEAD_CONN_TIMEOUT] = { .type = NLA_U64 }, }; static struct nla_policy nbd_sock_policy[NBD_SOCK_MAX + 1] = { @@ -1534,6 +1579,11 @@ again: nbd->tag_set.timeout = timeout * HZ; blk_queue_rq_timeout(nbd->disk->queue, timeout * HZ); } + if (info->attrs[NBD_ATTR_DEAD_CONN_TIMEOUT]) { + config->dead_conn_timeout = + nla_get_u64(info->attrs[NBD_ATTR_DEAD_CONN_TIMEOUT]); + config->dead_conn_timeout *= HZ; + } if (info->attrs[NBD_ATTR_SERVER_FLAGS]) config->flags = nla_get_u64(info->attrs[NBD_ATTR_SERVER_FLAGS]); @@ -1654,6 +1704,11 @@ static int nbd_genl_reconfigure(struct sk_buff *skb, struct genl_info *info) nbd->tag_set.timeout = timeout * HZ; blk_queue_rq_timeout(nbd->disk->queue, timeout * HZ); } + if (info->attrs[NBD_ATTR_DEAD_CONN_TIMEOUT]) { + config->dead_conn_timeout = + nla_get_u64(info->attrs[NBD_ATTR_DEAD_CONN_TIMEOUT]); + config->dead_conn_timeout *= HZ; + } if (info->attrs[NBD_ATTR_SOCKETS]) { struct nlattr *attr; |