diff options
| -rw-r--r-- | drivers/block/nbd.c | 141 | ||||
| -rw-r--r-- | include/uapi/linux/nbd-netlink.h | 1 |
2 files changed, 142 insertions, 0 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index efd2eba37c69..394ea891d909 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -785,6 +785,59 @@ static int nbd_add_socket(struct nbd_device *nbd, unsigned long arg, return 0; } +static int nbd_reconnect_socket(struct nbd_device *nbd, unsigned long arg) +{ + struct nbd_config *config = nbd->config; + struct socket *sock, *old; + struct recv_thread_args *args; + int i; + int err; + + sock = sockfd_lookup(arg, &err); + if (!sock) + return err; + + args = kzalloc(sizeof(*args), GFP_KERNEL); + if (!args) { + sockfd_put(sock); + return -ENOMEM; + } + + for (i = 0; i < config->num_connections; i++) { + struct nbd_sock *nsock = config->socks[i]; + + if (!nsock->dead) + continue; + + mutex_lock(&nsock->tx_lock); + if (!nsock->dead) { + mutex_unlock(&nsock->tx_lock); + continue; + } + sk_set_memalloc(sock->sk); + atomic_inc(&config->recv_threads); + refcount_inc(&nbd->config_refs); + old = nsock->sock; + nsock->fallback_index = -1; + nsock->sock = sock; + nsock->dead = false; + INIT_WORK(&args->work, recv_work); + args->index = i; + args->nbd = nbd; + mutex_unlock(&nsock->tx_lock); + sockfd_put(old); + + /* We take the tx_mutex in an error path in the recv_work, so we + * need to queue_work outside of the tx_mutex. + */ + queue_work(recv_workqueue, &args->work); + return 0; + } + sockfd_put(sock); + kfree(args); + return -ENOSPC; +} + /* Reset all properties of an NBD device */ static void nbd_reset(struct nbd_device *nbd) { @@ -1528,6 +1581,89 @@ static int nbd_genl_disconnect(struct sk_buff *skb, struct genl_info *info) return 0; } +static int nbd_genl_reconfigure(struct sk_buff *skb, struct genl_info *info) +{ + struct nbd_device *nbd = NULL; + struct nbd_config *config; + int index; + int ret = -EINVAL; + + if (!netlink_capable(skb, CAP_SYS_ADMIN)) + return -EPERM; + + if (!info->attrs[NBD_ATTR_INDEX]) { + printk(KERN_ERR "nbd: must specify a device to reconfigure\n"); + return -EINVAL; + } + index = nla_get_u32(info->attrs[NBD_ATTR_INDEX]); + mutex_lock(&nbd_index_mutex); + nbd = idr_find(&nbd_index_idr, index); + mutex_unlock(&nbd_index_mutex); + if (!nbd) { + printk(KERN_ERR "nbd: couldn't find a device at index %d\n", + index); + return -EINVAL; + } + + if (!refcount_inc_not_zero(&nbd->config_refs)) { + dev_err(nbd_to_dev(nbd), + "not configured, cannot reconfigure\n"); + return -EINVAL; + } + + mutex_lock(&nbd->config_lock); + config = nbd->config; + if (!test_bit(NBD_BOUND, &config->runtime_flags) || + !nbd->task_recv) { + dev_err(nbd_to_dev(nbd), + "not configured, cannot reconfigure\n"); + goto out; + } + + if (info->attrs[NBD_ATTR_TIMEOUT]) { + u64 timeout = nla_get_u64(info->attrs[NBD_ATTR_TIMEOUT]); + nbd->tag_set.timeout = timeout * HZ; + blk_queue_rq_timeout(nbd->disk->queue, timeout * HZ); + } + + if (info->attrs[NBD_ATTR_SOCKETS]) { + struct nlattr *attr; + int rem, fd; + + nla_for_each_nested(attr, info->attrs[NBD_ATTR_SOCKETS], + rem) { + struct nlattr *socks[NBD_SOCK_MAX+1]; + + if (nla_type(attr) != NBD_SOCK_ITEM) { + printk(KERN_ERR "nbd: socks must be embedded in a SOCK_ITEM attr\n"); + ret = -EINVAL; + goto out; + } + ret = nla_parse_nested(socks, NBD_SOCK_MAX, attr, + nbd_sock_policy); + if (ret != 0) { + printk(KERN_ERR "nbd: error processing sock list\n"); + ret = -EINVAL; + goto out; + } + if (!socks[NBD_SOCK_FD]) + continue; + fd = (int)nla_get_u32(socks[NBD_SOCK_FD]); + ret = nbd_reconnect_socket(nbd, fd); + if (ret) { + if (ret == -ENOSPC) + ret = 0; + goto out; + } + dev_info(nbd_to_dev(nbd), "reconnected socket\n"); + } + } +out: + mutex_unlock(&nbd->config_lock); + nbd_config_put(nbd); + return ret; +} + static const struct genl_ops nbd_connect_genl_ops[] = { { .cmd = NBD_CMD_CONNECT, @@ -1539,6 +1675,11 @@ static const struct genl_ops nbd_connect_genl_ops[] = { .policy = nbd_attr_policy, .doit = nbd_genl_disconnect, }, + { + .cmd = NBD_CMD_RECONFIGURE, + .policy = nbd_attr_policy, + .doit = nbd_genl_reconfigure, + }, }; static struct genl_family nbd_genl_family __ro_after_init = { diff --git a/include/uapi/linux/nbd-netlink.h b/include/uapi/linux/nbd-netlink.h index fd0f4e45f03e..f932f96a7c2f 100644 --- a/include/uapi/linux/nbd-netlink.h +++ b/include/uapi/linux/nbd-netlink.h @@ -62,6 +62,7 @@ enum { NBD_CMD_UNSPEC, NBD_CMD_CONNECT, NBD_CMD_DISCONNECT, + NBD_CMD_RECONFIGURE, __NBD_CMD_MAX, }; #define NBD_CMD_MAX (__NBD_CMD_MAX - 1) |