/* -*- mode: c; c-basic-offset: 8; -*- * * vim: noexpandtab sw=8 ts=8 sts=0: * * Copyright (C) 2004 Oracle. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. * * ---- * * Callers for this were originally written against a very simple synchronus * API. This implementation reflects those simple callers. Some day I'm sure * we'll need to move to a more robust posting/callback mechanism. * * Transmit calls pass in kernel virtual addresses and block copying this into * the socket's tx buffers via a usual blocking sendmsg. They'll block waiting * for a failed socket to timeout. TX callers can also pass in a poniter to an * 'int' which gets filled with an errno off the wire in response to the * message they send. * * Handlers for unsolicited messages are registered. Each socket has a page * that incoming data is copied into. First the header, then the data. * Handlers are called from only one thread with a reference to this per-socket * page. This page is destroyed after the handler call, so it can't be * referenced beyond the call. Handlers may block but are discouraged from * doing so. * * Any framing errors (bad magic, large payload lengths) close a connection. * * Our sock_container holds the state we associate with a socket. It's current * framing state is held there as well as the refcounting we do around when it * is safe to tear down the socket. The socket is only finally torn down from * the container when the container loses all of its references -- so as long * as you hold a ref on the container you can trust that the socket is valid * for use with kernel socket APIs. * * Connections are initiated between a pair of nodes when the node with the * higher node number gets a heartbeat callback which indicates that the lower * numbered node has started heartbeating. The lower numbered node is passive * and only accepts the connection if the higher numbered node is heartbeating. */ #include <linux/kernel.h> #include <linux/jiffies.h> #include <linux/slab.h> #include <linux/idr.h> #include <linux/kref.h> #include <net/tcp.h> #include <asm/uaccess.h> #include "heartbeat.h" #include "tcp.h" #include "nodemanager.h" #define MLOG_MASK_PREFIX ML_TCP #include "masklog.h" #include "quorum.h" #include "tcp_internal.h" /* * The linux network stack isn't sparse endian clean.. It has macros like * ntohs() which perform the endian checks and structs like sockaddr_in * which aren't annotated. So __force is found here to get the build * clean. When they emerge from the dark ages and annotate the code * we can remove these. */ #define SC_NODEF_FMT "node %s (num %u) at %u.%u.%u.%u:%u" #define SC_NODEF_ARGS(sc) sc->sc_node->nd_name, sc->sc_node->nd_num, \ NIPQUAD(sc->sc_node->nd_ipv4_address), \ ntohs(sc->sc_node->nd_ipv4_port) /* * In the following two log macros, the whitespace after the ',' just * before ##args is intentional. Otherwise, gcc 2.95 will eat the * previous token if args expands to nothing. */ #define msglog(hdr, fmt, args...) do { \ typeof(hdr) __hdr = (hdr); \ mlog(ML_MSG, "[mag %u len %u typ %u stat %d sys_stat %d " \ "key %08x num %u] " fmt, \ be16_to_cpu(__hdr->magic), be16_to_cpu(__hdr->data_len), \ be16_to_cpu(__hdr->msg_type), be32_to_cpu(__hdr->status), \ be32_to_cpu(__hdr->sys_status), be32_to_cpu(__hdr->key), \ be32_to_cpu(__hdr->msg_num) , ##args); \ } while (0) #define sclog(sc, fmt, args...) do { \ typeof(sc) __sc = (sc); \ mlog(ML_SOCKET, "[sc %p refs %d sock %p node %u page %p " \ "pg_off %zu] " fmt, __sc, \ atomic_read(&__sc->sc_kref.refcount), __sc->sc_sock, \ __sc->sc_node->nd_num, __sc->sc_page, __sc->sc_page_off , \ ##args); \ } while (0) static DEFINE_RWLOCK(o2net_handler_lock); static struct rb_root o2net_handler_tree = RB_ROOT; static struct o2net_node o2net_nodes[O2NM_MAX_NODES]; /* XXX someday we'll need better accounting */ static struct socket *o2net_listen_sock = NULL; /* * listen work is only queued by the listening socket callbacks on the * o2net_wq. teardown detaches the callbacks before destroying the workqueue. * quorum work is queued as sock containers are shutdown.. stop_listening * tears down all the node's sock containers, preventing future shutdowns * and queued quroum work, before canceling delayed quorum work and * destroying the work queue. */ static struct workqueue_struct *o2net_wq; static struct work_struct o2net_listen_work; static struct o2hb_callback_func o2net_hb_up, o2net_hb_down; #define O2NET_HB_PRI 0x1 static struct o2net_handshake *o2net_hand; static struct o2net_msg *o2net_keep_req, *o2net_keep_resp; static int o2net_sys_err_translations[O2NET_ERR_MAX] = {[O2NET_ERR_NONE] = 0, [O2NET_ERR_NO_HNDLR] = -ENOPROTOOPT, [O2NET_ERR_OVERFLOW] = -EOVERFLOW, [O2NET_ERR_DIED] = -EHOSTDOWN,}; /* can't quite avoid *all* internal declarations :/ */ static void o2net_sc_connect_completed(void *arg); static void o2net_rx_until_empty(void *arg); static void o2net_shutdown_sc(void *arg); static void o2net_listen_data_ready(struct sock *sk, int bytes); static void o2net_sc_send_keep_req(void *arg); static void o2net_idle_timer(unsigned long data); static void o2net_sc_postpone_idle(struct o2net_sock_container *sc); static inline int o2net_sys_err_to_errno(enum o2net_system_error err) { int trans; BUG_ON(err >= O2NET_ERR_MAX); trans = o2net_sys_err_translations[err]; /* Just in case we mess up the translation table above */ BUG_ON(err != O2NET_ERR_NONE && trans == 0); return trans; } static struct o2net_node * o2net_nn_from_num(u8 node_num) { BUG_ON(node_num >= ARRAY_SIZE(o2net_nodes)); return &o2net_nodes[node_num]; } static u8 o2net_num_from_nn(struct o2net_node *nn) { BUG_ON(nn == NULL); return nn - o2net_nodes; } /* ------------------------------------------------------------ */ static int o2net_prep_nsw(struct o2net_node *nn, struct o2net_status_wait *nsw) { int ret = 0; do { if (!idr_pre_get(&nn->nn_status_idr, GFP_ATOMIC)) { ret = -EAGAIN; break; } spin_lock(&nn->nn_lock); ret = idr_get_new(&nn->nn_status_idr, nsw, &nsw->ns_id); if (ret == 0) list_add_tail(&nsw->ns_node_item, &nn->nn_status_list); spin_unlock(&nn->nn_lock); } while (ret == -EAGAIN); if (ret == 0) { init_waitqueue_head(&nsw->ns_wq); nsw->ns_sys_status = O2NET_ERR_NONE; nsw->ns_status = 0; } return ret; } static void o2net_complete_nsw_locked(struct o2net_node *nn, struct o2net_status_wait *nsw, enum o2net_system_error sys_status, s32 status) { assert_spin_locked(&nn->nn_lock); if (!list_empty(&nsw->ns_node_item)) { list_del_init(&nsw->ns_node_item); nsw->ns_sys_status = sys_status; nsw->ns_status = status; idr_remove(&nn->nn_status_idr, nsw->ns_id); wake_up(&nsw->ns_wq); } } static void o2net_complete_nsw(struct o2net_node *nn, struct o2net_status_wait *nsw, u64 id, enum o2net_system_error sys_status, s32 status) { spin_lock(&nn->nn_lock); if (nsw == NULL) { if (id > INT_MAX) goto out; nsw = idr_find(&nn->nn_status_idr, id); if (nsw == NULL) goto out; } o2net_complete_nsw_locked(nn, nsw, sys_status, status); out: spin_unlock(&nn->nn_lock); return; } static void o2net_complete_nodes_nsw(struct o2net_node *nn) { struct list_head *iter, *tmp; unsigned int num_kills = 0; struct o2net_status_wait *nsw; assert_spin_locked(&nn->nn_lock); list_for_each_safe(iter, tmp, &nn->nn_status_list) { nsw = list_entry(iter, struct o2net_status_wait, ns_node_item); o2net_complete_nsw_locked(nn, nsw, O2NET_ERR_DIED, 0); num_kills++; } mlog(0, "completed %d messages for node %u\n", num_kills, o2net_num_from_nn(nn)); } static int o2net_nsw_completed(struct o2net_node *nn, struct o2net_status_wait *nsw) { int completed; spin_lock(&nn->nn_lock); completed = list_empty(&nsw->ns_node_item); spin_unlock(&nn->nn_lock); return completed; } /* ------------------------------------------------------------ */ static void sc_kref_release(struct kref *kref) { struct o2net_sock_container *sc = container_of(kref, struct o2net_sock_container, sc_kref); sclog(sc, "releasing\n"); if (sc->sc_sock) { sock_release(sc->sc_sock); sc->sc_sock = NULL; } o2nm_node_put(sc->sc_node); sc->sc_node = NULL; kfree(sc); } static void sc_put(struct o2net_sock_container *sc) { sclog(sc, "put\n"); kref_put(&sc->sc_kref, sc_kref_release); } static void sc_get(struct o2net_sock_container *sc) { sclog(sc, "get\n"); kref_get(&sc->sc_kref); } static struct o2net_sock_container *sc_alloc(struct o2nm_node *node) { struct o2net_sock_container *sc, *ret = NULL; struct page *page = NULL; page = alloc_page(GFP_NOFS); sc = kcalloc(1, sizeof(*sc), GFP_NOFS); if (sc == NULL || page == NULL) goto out; kref_init(&sc->sc_kref); o2nm_node_get(node); sc->sc_node = node; INIT_WORK(&sc->sc_connect_work, o2net_sc_connect_completed, sc); INIT_WORK(&sc->sc_rx_work, o2net_rx_until_empty, sc); INIT_WORK(&sc->sc_shutdown_work, o2net_shutdown_sc, sc); INIT_WORK(&sc->sc_keepalive_work, o2net_sc_send_keep_req, sc); init_timer(&sc->sc_idle_timeout); sc->sc_idle_timeout.function = o2net_idle_timer; sc->sc_idle_timeout.data = (unsigned long)sc; sclog(sc, "alloced\n"); ret = sc; sc->sc_page = page; sc = NULL; page = NULL; out: if (page) __free_page(page); kfree(sc); return ret; } /* ------------------------------------------------------------ */ static void o2net_sc_queue_work(struct o2net_sock_container *sc, struct work_struct *work) { sc_get(sc); if (!queue_work(o2net_wq, work)) sc_put(sc); } static void o2net_sc_queue_delayed_work(struct o2net_sock_container *sc, struct work_struct *work, int delay) { sc_get(sc); if (!queue_delayed_work(o2net_wq, work, delay)) sc_put(sc); } static void o2net_sc_cancel_delayed_work(struct o2net_sock_container *sc, struct work_struct *work) { if (cancel_delayed_work(work)) sc_put(sc); } static void o2net_set_nn_state(struct o2net_node *nn, struct o2net_sock_container *sc, unsigned valid, int err) { int was_valid = nn->nn_sc_valid; int was_err = nn->nn_persistent_error; struct o2net_sock_container *old_sc = nn->nn_sc; assert_spin_locked(&nn->nn_lock); /* the node num comparison and single connect/accept path should stop * an non-null sc from being overwritten with another */ BUG_ON(sc && nn->nn_sc && nn->nn_sc != sc); mlog_bug_on_msg(err && valid, "err %d valid %u\n", err, valid); mlog_bug_on_msg(valid && !sc, "valid %u sc %p\n", valid, sc); /* we won't reconnect after our valid conn goes away for * this hb iteration.. here so it shows up in the logs */ if (was_valid && !valid && err == 0) err = -ENOTCONN; mlog(ML_CONN, "node %u sc: %p -> %p, valid %u -> %u, err %d -> %d\n", o2net_num_from_nn(nn), nn->nn_sc, sc, nn->nn_sc_valid, valid, nn->nn_persistent_error, err); nn->nn_sc = sc; nn->nn_sc_valid = valid ? 1 : 0; nn->nn_persistent_error = err; /* mirrors o2net_tx_can_proceed() */ if (nn->nn_persistent_error || nn->nn_sc_valid) wake_up(&nn->nn_sc_wq); if (!was_err && nn->nn_persistent_error) { o2quo_conn_err(o2net_num_from_nn(nn)); queue_delayed_work(o2net_wq, &nn->nn_still_up, msecs_to_jiffies(O2NET_QUORUM_DELAY_MS)); } if (was_valid && !valid) { mlog(ML_NOTICE, "no longer connected to " SC_NODEF_FMT "\n", SC_NODEF_ARGS(old_sc)); o2net_complete_nodes_nsw(nn); } if (!was_valid && valid) { o2quo_conn_up(o2net_num_from_nn(nn)); /* this is a bit of a hack. we only try reconnecting * when heartbeating starts until we get a connection. * if that connection then dies we don't try reconnecting. * the only way to start connecting again is to down * heartbeat and bring it back up. */ cancel_delayed_work(&nn->nn_connect_expired); mlog(ML_NOTICE, "%s " SC_NODEF_FMT "\n", o2nm_this_node() > sc->sc_node->nd_num ? "connected to" : "accepted connection from", SC_NODEF_ARGS(sc)); } /* trigger the connecting worker func as long as we're not valid, * it will back off if it shouldn't connect. This can be called * from node config teardown and so needs to be careful about * the work queue actually being up. */ if (!valid && o2net_wq) { unsigned long delay; /* delay if we're withing a RECONNECT_DELAY of the * last attempt */ delay = (nn->nn_last_connect_attempt + msecs_to_jiffies(O2NET_RECONNECT_DELAY_MS)) - jiffies; if (delay > msecs_to_jiffies(O2NET_RECONNECT_DELAY_MS)) delay = 0; mlog(ML_CONN, "queueing conn attempt in %lu jiffies\n", delay); queue_delayed_work(o2net_wq, &nn->nn_connect_work, delay); } /* keep track of the nn's sc ref for the caller */ if ((old_sc == NULL) && sc) sc_get(sc); if (old_sc && (old_sc != sc)) { o2net_sc_queue_work(old_sc, &old_sc->sc_shutdown_work); sc_put(old_sc); } } /* see o2net_register_callbacks() */ static void o2net_data_ready(struct sock *sk, int bytes) { void (*ready)(struct sock *sk, int bytes); read_lock(&sk->sk_callback_lock); if (sk->sk_user_data) { struct o2net_sock_container *sc = sk->sk_user_data; sclog(sc, "data_ready hit\n"); do_gettimeofday(&sc->sc_tv_data_ready); o2net_sc_queue_work(sc, &sc->sc_rx_work); ready = sc->sc_data_ready; } else { ready = sk->sk_data_ready; } read_unlock(&sk->sk_callback_lock); ready(sk, bytes); } /* see o2net_register_callbacks() */ static void o2net_state_change(struct sock *sk) { void (*state_change)(struct sock *sk); struct o2net_sock_container *sc; read_lock(&sk->sk_callback_lock); sc = sk->sk_user_data; if (sc == NULL) { state_change = sk->sk_state_change; goto out; } sclog(sc, "state_change to %d\n", sk->sk_state); state_change = sc->sc_state_change; switch(sk->sk_state) { /* ignore connecting sockets as they make progress */ case TCP_SYN_SENT: case TCP_SYN_RECV: break; case TCP_ESTABLISHED: o2net_sc_queue_work(sc, &sc->sc_connect_work); break; default: o2net_sc_queue_work(sc, &sc->sc_shutdown_work); break; } out: read_unlock(&sk->sk_callback_lock); state_change(sk); } /* * we register callbacks so we can queue work on events before calling * the original callbacks. our callbacks our careful to test user_data * to discover when they've reaced with o2net_unregister_callbacks(). */ static void o2net_register_callbacks(struct sock *sk, struct o2net_sock_container *sc) { write_lock_bh(&sk->sk_callback_lock); /* accepted sockets inherit the old listen socket data ready */ if (sk->sk_data_ready == o2net_listen_data_ready) { sk->sk_data_ready = sk->sk_user_data; sk->sk_user_data = NULL; } BUG_ON(sk->sk_user_data != NULL); sk->sk_user_data = sc; sc_get(sc); sc->sc_data_ready = sk->sk_data_ready; sc->sc_state_change = sk->sk_state_change; sk->sk_data_ready = o2net_data_ready; sk->sk_state_change = o2net_state_change; write_unlock_bh(&sk->sk_callback_lock); } static int o2net_unregister_callbacks(struct sock *sk, struct o2net_sock_container *sc) { int ret = 0; write_lock_bh(&sk->sk_callback_lock); if (sk->sk_user_data == sc) { ret = 1; sk->sk_user_data = NULL; sk->sk_data_ready = sc->sc_data_ready; sk->sk_state_change = sc->sc_state_change; } write_unlock_bh(&sk->sk_callback_lock); return ret; } /* * this is a little helper that is called by callers who have seen a problem * with an sc and want to detach it from the nn if someone already hasn't beat * them to it. if an error is given then the shutdown will be persistent * and pending transmits will be canceled. */ static void o2net_ensure_shutdown(struct o2net_node *nn, struct o2net_sock_container *sc, int err) { spin_lock(&nn->nn_lock); if (nn->nn_sc == sc) o2net_set_nn_state(nn, NULL, 0, err); spin_unlock(&nn->nn_lock); } /* * This work queue function performs the blocking parts of socket shutdown. A * few paths lead here. set_nn_state will trigger this callback if it sees an * sc detached from the nn. state_change will also trigger this callback * directly when it sees errors. In that case we need to call set_nn_state * ourselves as state_change couldn't get the nn_lock and call set_nn_state * itself. */ static void o2net_shutdown_sc(void *arg) { struct o2net_sock_container *sc = arg; struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); sclog(sc, "shutting down\n"); /* drop the callbacks ref and call shutdown only once */ if (o2net_unregister_callbacks(sc->sc_sock->sk, sc)) { /* we shouldn't flush as we're in the thread, the * races with pending sc work structs are harmless */ del_timer_sync(&sc->sc_idle_timeout); o2net_sc_cancel_delayed_work(sc, &sc->sc_keepalive_work); sc_put(sc); sc->sc_sock->ops->shutdown(sc->sc_sock, RCV_SHUTDOWN|SEND_SHUTDOWN); } /* not fatal so failed connects before the other guy has our * heartbeat can be retried */ o2net_ensure_shutdown(nn, sc, 0); sc_put(sc); } /* ------------------------------------------------------------ */ static int o2net_handler_cmp(struct o2net_msg_handler *nmh, u32 msg_type, u32 key) { int ret = memcmp(&nmh->nh_key, &key, sizeof(key)); if (ret == 0) ret = memcmp(&nmh->nh_msg_type, &msg_type, sizeof(msg_type)); return ret; } static struct o2net_msg_handler * o2net_handler_tree_lookup(u32 msg_type, u32 key, struct rb_node ***ret_p, struct rb_node **ret_parent) { struct rb_node **p = &o2net_handler_tree.rb_node; struct rb_node *parent = NULL; struct o2net_msg_handler *nmh, *ret = NULL; int cmp; while (*p) { parent = *p; nmh = rb_entry(parent, struct o2net_msg_handler, nh_node); cmp = o2net_handler_cmp(nmh, msg_type, key); if (cmp < 0) p = &(*p)->rb_left; else if (cmp > 0) p = &(*p)->rb_right; else { ret = nmh; break; } } if (ret_p != NULL) *ret_p = p; if (ret_parent != NULL) *ret_parent = parent; return ret; } static void o2net_handler_kref_release(struct kref *kref) { struct o2net_msg_handler *nmh; nmh = container_of(kref, struct o2net_msg_handler, nh_kref); kfree(nmh); } static void o2net_handler_put(struct o2net_msg_handler *nmh) { kref_put(&nmh->nh_kref, o2net_handler_kref_release); } /* max_len is protection for the handler func. incoming messages won't * be given to the handler if their payload is longer than the max. */ int o2net_register_handler(u32 msg_type, u32 key, u32 max_len, o2net_msg_handler_func *func, void *data, struct list_head *unreg_list) { struct o2net_msg_handler *nmh = NULL; struct rb_node **p, *parent; int ret = 0; if (max_len > O2NET_MAX_PAYLOAD_BYTES) { mlog(0, "max_len for message handler out of range: %u\n", max_len); ret = -EINVAL; goto out; } if (!msg_type) { mlog(0, "no message type provided: %u, %p\n", msg_type, func); ret = -EINVAL; goto out; } if (!func) { mlog(0, "no message handler provided: %u, %p\n", msg_type, func); ret = -EINVAL; goto out; } nmh = kcalloc(1, sizeof(struct o2net_msg_handler), GFP_NOFS); if (nmh == NULL) { ret = -ENOMEM; goto out; } nmh->nh_func = func; nmh->nh_func_data = data; nmh->nh_msg_type = msg_type; nmh->nh_max_len = max_len; nmh->nh_key = key; /* the tree and list get this ref.. they're both removed in * unregister when this ref is dropped */ kref_init(&nmh->nh_kref); INIT_LIST_HEAD(&nmh->nh_unregister_item); write_lock(&o2net_handler_lock); if (o2net_handler_tree_lookup(msg_type, key, &p, &parent)) ret = -EEXIST; else { rb_link_node(&nmh->nh_node, parent, p); rb_insert_color(&nmh->nh_node, &o2net_handler_tree); list_add_tail(&nmh->nh_unregister_item, unreg_list); mlog(ML_TCP, "registered handler func %p type %u key %08x\n", func, msg_type, key); /* we've had some trouble with handlers seemingly vanishing. */ mlog_bug_on_msg(o2net_handler_tree_lookup(msg_type, key, &p, &parent) == NULL, "couldn't find handler we *just* registerd " "for type %u key %08x\n", msg_type, key); } write_unlock(&o2net_handler_lock); if (ret) goto out; out: if (ret) kfree(nmh); return ret; } EXPORT_SYMBOL_GPL(o2net_register_handler); void o2net_unregister_handler_list(struct list_head *list) { struct list_head *pos, *n; struct o2net_msg_handler *nmh; write_lock(&o2net_handler_lock); list_for_each_safe(pos, n, list) { nmh = list_entry(pos, struct o2net_msg_handler, nh_unregister_item); mlog(ML_TCP, "unregistering handler func %p type %u key %08x\n", nmh->nh_func, nmh->nh_msg_type, nmh->nh_key); rb_erase(&nmh->nh_node, &o2net_handler_tree); list_del_init(&nmh->nh_unregister_item); kref_put(&nmh->nh_kref, o2net_handler_kref_release); } write_unlock(&o2net_handler_lock); } EXPORT_SYMBOL_GPL(o2net_unregister_handler_list); static struct o2net_msg_handler *o2net_handler_get(u32 msg_type, u32 key) { struct o2net_msg_handler *nmh; read_lock(&o2net_handler_lock); nmh = o2net_handler_tree_lookup(msg_type, key, NULL, NULL); if (nmh) kref_get(&nmh->nh_kref); read_unlock(&o2net_handler_lock); return nmh; } /* ------------------------------------------------------------ */ static int o2net_recv_tcp_msg(struct socket *sock, void *data, size_t len) { int ret; mm_segment_t oldfs; struct kvec vec = { .iov_len = len, .iov_base = data, }; struct msghdr msg = { .msg_iovlen = 1, .msg_iov = (struct iovec *)&vec, .msg_flags = MSG_DONTWAIT, }; oldfs = get_fs(); set_fs(get_ds()); ret = sock_recvmsg(sock, &msg, len, msg.msg_flags); set_fs(oldfs); return ret; } static int o2net_send_tcp_msg(struct socket *sock, struct kvec *vec, size_t veclen, size_t total) { int ret; mm_segment_t oldfs; struct msghdr msg = { .msg_iov = (struct iovec *)vec, .msg_iovlen = veclen, }; if (sock == NULL) { ret = -EINVAL; goto out; } oldfs = get_fs(); set_fs(get_ds()); ret = sock_sendmsg(sock, &msg, total); set_fs(oldfs); if (ret != total) { mlog(ML_ERROR, "sendmsg returned %d instead of %zu\n", ret, total); if (ret >= 0) ret = -EPIPE; /* should be smarter, I bet */ goto out; } ret = 0; out: if (ret < 0) mlog(0, "returning error: %d\n", ret); return ret; } static void o2net_sendpage(struct o2net_sock_container *sc, void *kmalloced_virt, size_t size) { struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); ssize_t ret; ret = sc->sc_sock->ops->sendpage(sc->sc_sock, virt_to_page(kmalloced_virt), (long)kmalloced_virt & ~PAGE_MASK, size, MSG_DONTWAIT); if (ret != size) { mlog(ML_ERROR, "sendpage of size %zu to " SC_NODEF_FMT " failed with %zd\n", size, SC_NODEF_ARGS(sc), ret); o2net_ensure_shutdown(nn, sc, 0); } } static void o2net_init_msg(struct o2net_msg *msg, u16 data_len, u16 msg_type, u32 key) { memset(msg, 0, sizeof(struct o2net_msg)); msg->magic = cpu_to_be16(O2NET_MSG_MAGIC); msg->data_len = cpu_to_be16(data_len); msg->msg_type = cpu_to_be16(msg_type); msg->sys_status = cpu_to_be32(O2NET_ERR_NONE); msg->status = 0; msg->key = cpu_to_be32(key); } static int o2net_tx_can_proceed(struct o2net_node *nn, struct o2net_sock_container **sc_ret, int *error) { int ret = 0; spin_lock(&nn->nn_lock); if (nn->nn_persistent_error) { ret = 1; *sc_ret = NULL; *error = nn->nn_persistent_error; } else if (nn->nn_sc_valid) { kref_get(&nn->nn_sc->sc_kref); ret = 1; *sc_ret = nn->nn_sc; *error = 0; } spin_unlock(&nn->nn_lock); return ret; } int o2net_send_message_vec(u32 msg_type, u32 key, struct kvec *caller_vec, size_t caller_veclen, u8 target_node, int *status) { int ret, error = 0; struct o2net_msg *msg = NULL; size_t veclen, caller_bytes = 0; struct kvec *vec = NULL; struct o2net_sock_container *sc = NULL; struct o2net_node *nn = o2net_nn_from_num(target_node); struct o2net_status_wait nsw = { .ns_node_item = LIST_HEAD_INIT(nsw.ns_node_item), }; if (o2net_wq == NULL) { mlog(0, "attempt to tx without o2netd running\n"); ret = -ESRCH; goto out; } if (caller_veclen == 0) { mlog(0, "bad kvec array length\n"); ret = -EINVAL; goto out; } caller_bytes = iov_length((struct iovec *)caller_vec, caller_veclen); if (caller_bytes > O2NET_MAX_PAYLOAD_BYTES) { mlog(0, "total payload len %zu too large\n", caller_bytes); ret = -EINVAL; goto out; } if (target_node == o2nm_this_node()) { ret = -ELOOP; goto out; } ret = wait_event_interruptible(nn->nn_sc_wq, o2net_tx_can_proceed(nn, &sc, &error)); if (!ret && error) ret = error; if (ret) goto out; veclen = caller_veclen + 1; vec = kmalloc(sizeof(struct kvec) * veclen, GFP_ATOMIC); if (vec == NULL) { mlog(0, "failed to %zu element kvec!\n", veclen); ret = -ENOMEM; goto out; } msg = kmalloc(sizeof(struct o2net_msg), GFP_ATOMIC); if (!msg) { mlog(0, "failed to allocate a o2net_msg!\n"); ret = -ENOMEM; goto out; } o2net_init_msg(msg, caller_bytes, msg_type, key); vec[0].iov_len = sizeof(struct o2net_msg); vec[0].iov_base = msg; memcpy(&vec[1], caller_vec, caller_veclen * sizeof(struct kvec)); ret = o2net_prep_nsw(nn, &nsw); if (ret) goto out; msg->msg_num = cpu_to_be32(nsw.ns_id); /* finally, convert the message header to network byte-order * and send */ ret = o2net_send_tcp_msg(sc->sc_sock, vec, veclen, sizeof(struct o2net_msg) + caller_bytes); msglog(msg, "sending returned %d\n", ret); if (ret < 0) { mlog(0, "error returned from o2net_send_tcp_msg=%d\n", ret); goto out; } /* wait on other node's handler */ wait_event(nsw.ns_wq, o2net_nsw_completed(nn, &nsw)); /* Note that we avoid overwriting the callers status return * variable if a system error was reported on the other * side. Callers beware. */ ret = o2net_sys_err_to_errno(nsw.ns_sys_status); if (status && !ret) *status = nsw.ns_status; mlog(0, "woken, returning system status %d, user status %d\n", ret, nsw.ns_status); out: if (sc) sc_put(sc); if (vec) kfree(vec); if (msg) kfree(msg); o2net_complete_nsw(nn, &nsw, 0, 0, 0); return ret; } EXPORT_SYMBOL_GPL(o2net_send_message_vec); int o2net_send_message(u32 msg_type, u32 key, void *data, u32 len, u8 target_node, int *status) { struct kvec vec = { .iov_base = data, .iov_len = len, }; return o2net_send_message_vec(msg_type, key, &vec, 1, target_node, status); } EXPORT_SYMBOL_GPL(o2net_send_message); static int o2net_send_status_magic(struct socket *sock, struct o2net_msg *hdr, enum o2net_system_error syserr, int err) { struct kvec vec = { .iov_base = hdr, .iov_len = sizeof(struct o2net_msg), }; BUG_ON(syserr >= O2NET_ERR_MAX); /* leave other fields intact from the incoming message, msg_num * in particular */ hdr->sys_status = cpu_to_be32(syserr); hdr->status = cpu_to_be32(err); hdr->magic = cpu_to_be16(O2NET_MSG_STATUS_MAGIC); // twiddle the magic hdr->data_len = 0; msglog(hdr, "about to send status magic %d\n", err); /* hdr has been in host byteorder this whole time */ return o2net_send_tcp_msg(sock, &vec, 1, sizeof(struct o2net_msg)); } /* this returns -errno if the header was unknown or too large, etc. * after this is called the buffer us reused for the next message */ static int o2net_process_message(struct o2net_sock_container *sc, struct o2net_msg *hdr) { struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); int ret = 0, handler_status; enum o2net_system_error syserr; struct o2net_msg_handler *nmh = NULL; msglog(hdr, "processing message\n"); o2net_sc_postpone_idle(sc); switch(be16_to_cpu(hdr->magic)) { case O2NET_MSG_STATUS_MAGIC: /* special type for returning message status */ o2net_complete_nsw(nn, NULL, be32_to_cpu(hdr->msg_num), be32_to_cpu(hdr->sys_status), be32_to_cpu(hdr->status)); goto out; case O2NET_MSG_KEEP_REQ_MAGIC: o2net_sendpage(sc, o2net_keep_resp, sizeof(*o2net_keep_resp)); goto out; case O2NET_MSG_KEEP_RESP_MAGIC: goto out; case O2NET_MSG_MAGIC: break; default: msglog(hdr, "bad magic\n"); ret = -EINVAL; goto out; break; } /* find a handler for it */ handler_status = 0; nmh = o2net_handler_get(be16_to_cpu(hdr->msg_type), be32_to_cpu(hdr->key)); if (!nmh) { mlog(ML_TCP, "couldn't find handler for type %u key %08x\n", be16_to_cpu(hdr->msg_type), be32_to_cpu(hdr->key)); syserr = O2NET_ERR_NO_HNDLR; goto out_respond; } syserr = O2NET_ERR_NONE; if (be16_to_cpu(hdr->data_len) > nmh->nh_max_len) syserr = O2NET_ERR_OVERFLOW; if (syserr != O2NET_ERR_NONE) goto out_respond; do_gettimeofday(&sc->sc_tv_func_start); sc->sc_msg_key = be32_to_cpu(hdr->key); sc->sc_msg_type = be16_to_cpu(hdr->msg_type); handler_status = (nmh->nh_func)(hdr, sizeof(struct o2net_msg) + be16_to_cpu(hdr->data_len), nmh->nh_func_data); do_gettimeofday(&sc->sc_tv_func_stop); out_respond: /* this destroys the hdr, so don't use it after this */ ret = o2net_send_status_magic(sc->sc_sock, hdr, syserr, handler_status); hdr = NULL; mlog(0, "sending handler status %d, syserr %d returned %d\n", handler_status, syserr, ret); out: if (nmh) o2net_handler_put(nmh); return ret; } static int o2net_check_handshake(struct o2net_sock_container *sc) { struct o2net_handshake *hand = page_address(sc->sc_page); struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); if (hand->protocol_version != cpu_to_be64(O2NET_PROTOCOL_VERSION)) { mlog(ML_NOTICE, SC_NODEF_FMT " advertised net protocol " "version %llu but %llu is required, disconnecting\n", SC_NODEF_ARGS(sc), (unsigned long long)be64_to_cpu(hand->protocol_version), O2NET_PROTOCOL_VERSION); /* don't bother reconnecting if its the wrong version. */ o2net_ensure_shutdown(nn, sc, -ENOTCONN); return -1; } sc->sc_handshake_ok = 1; spin_lock(&nn->nn_lock); /* set valid and queue the idle timers only if it hasn't been * shut down already */ if (nn->nn_sc == sc) { o2net_sc_postpone_idle(sc); o2net_set_nn_state(nn, sc, 1, 0); } spin_unlock(&nn->nn_lock); /* shift everything up as though it wasn't there */ sc->sc_page_off -= sizeof(struct o2net_handshake); if (sc->sc_page_off) memmove(hand, hand + 1, sc->sc_page_off); return 0; } /* this demuxes the queued rx bytes into header or payload bits and calls * handlers as each full message is read off the socket. it returns -error, * == 0 eof, or > 0 for progress made.*/ static int o2net_advance_rx(struct o2net_sock_container *sc) { struct o2net_msg *hdr; int ret = 0; void *data; size_t datalen; sclog(sc, "receiving\n"); do_gettimeofday(&sc->sc_tv_advance_start); /* do we need more header? */ if (sc->sc_page_off < sizeof(struct o2net_msg)) { data = page_address(sc->sc_page) + sc->sc_page_off; datalen = sizeof(struct o2net_msg) - sc->sc_page_off; ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen); if (ret > 0) { sc->sc_page_off += ret; /* this working relies on the handshake being * smaller than the normal message header */ if (sc->sc_page_off >= sizeof(struct o2net_handshake)&& !sc->sc_handshake_ok && o2net_check_handshake(sc)) { ret = -EPROTO; goto out; } /* only swab incoming here.. we can * only get here once as we cross from * being under to over */ if (sc->sc_page_off == sizeof(struct o2net_msg)) { hdr = page_address(sc->sc_page); if (be16_to_cpu(hdr->data_len) > O2NET_MAX_PAYLOAD_BYTES) ret = -EOVERFLOW; } } if (ret <= 0) goto out; } if (sc->sc_page_off < sizeof(struct o2net_msg)) { /* oof, still don't have a header */ goto out; } /* this was swabbed above when we first read it */ hdr = page_address(sc->sc_page); msglog(hdr, "at page_off %zu\n", sc->sc_page_off); /* do we need more payload? */ if (sc->sc_page_off - sizeof(struct o2net_msg) < be16_to_cpu(hdr->data_len)) { /* need more payload */ data = page_address(sc->sc_page) + sc->sc_page_off; datalen = (sizeof(struct o2net_msg) + be16_to_cpu(hdr->data_len)) - sc->sc_page_off; ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen); if (ret > 0) sc->sc_page_off += ret; if (ret <= 0) goto out; } if (sc->sc_page_off - sizeof(struct o2net_msg) == be16_to_cpu(hdr->data_len)) { /* we can only get here once, the first time we read * the payload.. so set ret to progress if the handler * works out. after calling this the message is toast */ ret = o2net_process_message(sc, hdr); if (ret == 0) ret = 1; sc->sc_page_off = 0; } out: sclog(sc, "ret = %d\n", ret); do_gettimeofday(&sc->sc_tv_advance_stop); return ret; } /* this work func is triggerd by data ready. it reads until it can read no * more. it interprets 0, eof, as fatal. if data_ready hits while we're doing * our work the work struct will be marked and we'll be called again. */ static void o2net_rx_until_empty(void *arg) { struct o2net_sock_container *sc = arg; int ret; do { ret = o2net_advance_rx(sc); } while (ret > 0); if (ret <= 0 && ret != -EAGAIN) { struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); sclog(sc, "saw error %d, closing\n", ret); /* not permanent so read failed handshake can retry */ o2net_ensure_shutdown(nn, sc, 0); } sc_put(sc); } static int o2net_set_nodelay(struct socket *sock) { int ret, val = 1; mm_segment_t oldfs; oldfs = get_fs(); set_fs(KERNEL_DS); /* * Dear unsuspecting programmer, * * Don't use sock_setsockopt() for SOL_TCP. It doesn't check its level * argument and assumes SOL_SOCKET so, say, your TCP_NODELAY will * silently turn into SO_DEBUG. * * Yours, * Keeper of hilariously fragile interfaces. */ ret = sock->ops->setsockopt(sock, SOL_TCP, TCP_NODELAY, (char __user *)&val, sizeof(val)); set_fs(oldfs); return ret; } /* ------------------------------------------------------------ */ /* called when a connect completes and after a sock is accepted. the * rx path will see the response and mark the sc valid */ static void o2net_sc_connect_completed(void *arg) { struct o2net_sock_container *sc = arg; mlog(ML_MSG, "sc sending handshake with ver %llu id %llx\n", (unsigned long long)O2NET_PROTOCOL_VERSION, (unsigned long long)be64_to_cpu(o2net_hand->connector_id)); o2net_sendpage(sc, o2net_hand, sizeof(*o2net_hand)); sc_put(sc); } /* this is called as a work_struct func. */ static void o2net_sc_send_keep_req(void *arg) { struct o2net_sock_container *sc = arg; o2net_sendpage(sc, o2net_keep_req, sizeof(*o2net_keep_req)); sc_put(sc); } /* socket shutdown does a del_timer_sync against this as it tears down. * we can't start this timer until we've got to the point in sc buildup * where shutdown is going to be involved */ static void o2net_idle_timer(unsigned long data) { struct o2net_sock_container *sc = (struct o2net_sock_container *)data; struct timeval now; do_gettimeofday(&now); mlog(ML_NOTICE, "connection to " SC_NODEF_FMT " has been idle for 10 " "seconds, shutting it down.\n", SC_NODEF_ARGS(sc)); mlog(ML_NOTICE, "here are some times that might help debug the " "situation: (tmr %ld.%ld now %ld.%ld dr %ld.%ld adv " "%ld.%ld:%ld.%ld func (%08x:%u) %ld.%ld:%ld.%ld)\n", sc->sc_tv_timer.tv_sec, (long) sc->sc_tv_timer.tv_usec, now.tv_sec, (long) now.tv_usec, sc->sc_tv_data_ready.tv_sec, (long) sc->sc_tv_data_ready.tv_usec, sc->sc_tv_advance_start.tv_sec, (long) sc->sc_tv_advance_start.tv_usec, sc->sc_tv_advance_stop.tv_sec, (long) sc->sc_tv_advance_stop.tv_usec, sc->sc_msg_key, sc->sc_msg_type, sc->sc_tv_func_start.tv_sec, (long) sc->sc_tv_func_start.tv_usec, sc->sc_tv_func_stop.tv_sec, (long) sc->sc_tv_func_stop.tv_usec); o2net_sc_queue_work(sc, &sc->sc_shutdown_work); } static void o2net_sc_postpone_idle(struct o2net_sock_container *sc) { o2net_sc_cancel_delayed_work(sc, &sc->sc_keepalive_work); o2net_sc_queue_delayed_work(sc, &sc->sc_keepalive_work, O2NET_KEEPALIVE_DELAY_SECS * HZ); do_gettimeofday(&sc->sc_tv_timer); mod_timer(&sc->sc_idle_timeout, jiffies + (O2NET_IDLE_TIMEOUT_SECS * HZ)); } /* this work func is kicked whenever a path sets the nn state which doesn't * have valid set. This includes seeing hb come up, losing a connection, * having a connect attempt fail, etc. This centralizes the logic which decides * if a connect attempt should be made or if we should give up and all future * transmit attempts should fail */ static void o2net_start_connect(void *arg) { struct o2net_node *nn = arg; struct o2net_sock_container *sc = NULL; struct o2nm_node *node = NULL, *mynode = NULL; struct socket *sock = NULL; struct sockaddr_in myaddr = {0, }, remoteaddr = {0, }; int ret = 0; /* if we're greater we initiate tx, otherwise we accept */ if (o2nm_this_node() <= o2net_num_from_nn(nn)) goto out; /* watch for racing with tearing a node down */ node = o2nm_get_node_by_num(o2net_num_from_nn(nn)); if (node == NULL) { ret = 0; goto out; } mynode = o2nm_get_node_by_num(o2nm_this_node()); if (mynode == NULL) { ret = 0; goto out; } spin_lock(&nn->nn_lock); /* see if we already have one pending or have given up */ if (nn->nn_sc || nn->nn_persistent_error) arg = NULL; spin_unlock(&nn->nn_lock); if (arg == NULL) /* *shrug*, needed some indicator */ goto out; nn->nn_last_connect_attempt = jiffies; sc = sc_alloc(node); if (sc == NULL) { mlog(0, "couldn't allocate sc\n"); ret = -ENOMEM; goto out; } ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock); if (ret < 0) { mlog(0, "can't create socket: %d\n", ret); goto out; } sc->sc_sock = sock; /* freed by sc_kref_release */ sock->sk->sk_allocation = GFP_ATOMIC; myaddr.sin_family = AF_INET; myaddr.sin_addr.s_addr = (__force u32)mynode->nd_ipv4_address; myaddr.sin_port = (__force u16)htons(0); /* any port */ ret = sock->ops->bind(sock, (struct sockaddr *)&myaddr, sizeof(myaddr)); if (ret) { mlog(ML_ERROR, "bind failed with %d at address %u.%u.%u.%u\n", ret, NIPQUAD(mynode->nd_ipv4_address)); goto out; } ret = o2net_set_nodelay(sc->sc_sock); if (ret) { mlog(ML_ERROR, "setting TCP_NODELAY failed with %d\n", ret); goto out; } o2net_register_callbacks(sc->sc_sock->sk, sc); spin_lock(&nn->nn_lock); /* handshake completion will set nn->nn_sc_valid */ o2net_set_nn_state(nn, sc, 0, 0); spin_unlock(&nn->nn_lock); remoteaddr.sin_family = AF_INET; remoteaddr.sin_addr.s_addr = (__force u32)node->nd_ipv4_address; remoteaddr.sin_port = (__force u16)node->nd_ipv4_port; ret = sc->sc_sock->ops->connect(sc->sc_sock, (struct sockaddr *)&remoteaddr, sizeof(remoteaddr), O_NONBLOCK); if (ret == -EINPROGRESS) ret = 0; out: if (ret) { mlog(ML_NOTICE, "connect attempt to " SC_NODEF_FMT " failed " "with errno %d\n", SC_NODEF_ARGS(sc), ret); /* 0 err so that another will be queued and attempted * from set_nn_state */ if (sc) o2net_ensure_shutdown(nn, sc, 0); } if (sc) sc_put(sc); if (node) o2nm_node_put(node); if (mynode) o2nm_node_put(mynode); return; } static void o2net_connect_expired(void *arg) { struct o2net_node *nn = arg; spin_lock(&nn->nn_lock); if (!nn->nn_sc_valid) { mlog(ML_ERROR, "no connection established with node %u after " "%u seconds, giving up and returning errors.\n", o2net_num_from_nn(nn), O2NET_IDLE_TIMEOUT_SECS); o2net_set_nn_state(nn, NULL, 0, -ENOTCONN); } spin_unlock(&nn->nn_lock); } static void o2net_still_up(void *arg) { struct o2net_node *nn = arg; o2quo_hb_still_up(o2net_num_from_nn(nn)); } /* ------------------------------------------------------------ */ void o2net_disconnect_node(struct o2nm_node *node) { struct o2net_node *nn = o2net_nn_from_num(node->nd_num); /* don't reconnect until it's heartbeating again */ spin_lock(&nn->nn_lock); o2net_set_nn_state(nn, NULL, 0, -ENOTCONN); spin_unlock(&nn->nn_lock); if (o2net_wq) { cancel_delayed_work(&nn->nn_connect_expired); cancel_delayed_work(&nn->nn_connect_work); cancel_delayed_work(&nn->nn_still_up); flush_workqueue(o2net_wq); } } static void o2net_hb_node_down_cb(struct o2nm_node *node, int node_num, void *data) { o2quo_hb_down(node_num); if (node_num != o2nm_this_node()) o2net_disconnect_node(node); } static void o2net_hb_node_up_cb(struct o2nm_node *node, int node_num, void *data) { struct o2net_node *nn = o2net_nn_from_num(node_num); o2quo_hb_up(node_num); /* ensure an immediate connect attempt */ nn->nn_last_connect_attempt = jiffies - (msecs_to_jiffies(O2NET_RECONNECT_DELAY_MS) + 1); if (node_num != o2nm_this_node()) { /* heartbeat doesn't work unless a local node number is * configured and doing so brings up the o2net_wq, so we can * use it.. */ queue_delayed_work(o2net_wq, &nn->nn_connect_expired, O2NET_IDLE_TIMEOUT_SECS * HZ); /* believe it or not, accept and node hearbeating testing * can succeed for this node before we got here.. so * only use set_nn_state to clear the persistent error * if that hasn't already happened */ spin_lock(&nn->nn_lock); if (nn->nn_persistent_error) o2net_set_nn_state(nn, NULL, 0, 0); spin_unlock(&nn->nn_lock); } } void o2net_unregister_hb_callbacks(void) { int ret; ret = o2hb_unregister_callback(&o2net_hb_up); if (ret < 0) mlog(ML_ERROR, "Status return %d unregistering heartbeat up " "callback!\n", ret); ret = o2hb_unregister_callback(&o2net_hb_down); if (ret < 0) mlog(ML_ERROR, "Status return %d unregistering heartbeat down " "callback!\n", ret); } int o2net_register_hb_callbacks(void) { int ret; o2hb_setup_callback(&o2net_hb_down, O2HB_NODE_DOWN_CB, o2net_hb_node_down_cb, NULL, O2NET_HB_PRI); o2hb_setup_callback(&o2net_hb_up, O2HB_NODE_UP_CB, o2net_hb_node_up_cb, NULL, O2NET_HB_PRI); ret = o2hb_register_callback(&o2net_hb_up); if (ret == 0) ret = o2hb_register_callback(&o2net_hb_down); if (ret) o2net_unregister_hb_callbacks(); return ret; } /* ------------------------------------------------------------ */ static int o2net_accept_one(struct socket *sock) { int ret, slen; struct sockaddr_in sin; struct socket *new_sock = NULL; struct o2nm_node *node = NULL; struct o2net_sock_container *sc = NULL; struct o2net_node *nn; BUG_ON(sock == NULL); ret = sock_create_lite(sock->sk->sk_family, sock->sk->sk_type, sock->sk->sk_protocol, &new_sock); if (ret) goto out; new_sock->type = sock->type; new_sock->ops = sock->ops; ret = sock->ops->accept(sock, new_sock, O_NONBLOCK); if (ret < 0) goto out; new_sock->sk->sk_allocation = GFP_ATOMIC; ret = o2net_set_nodelay(new_sock); if (ret) { mlog(ML_ERROR, "setting TCP_NODELAY failed with %d\n", ret); goto out; } slen = sizeof(sin); ret = new_sock->ops->getname(new_sock, (struct sockaddr *) &sin, &slen, 1); if (ret < 0) goto out; node = o2nm_get_node_by_ip((__force __be32)sin.sin_addr.s_addr); if (node == NULL) { mlog(ML_NOTICE, "attempt to connect from unknown node at " "%u.%u.%u.%u:%d\n", NIPQUAD(sin.sin_addr.s_addr), ntohs((__force __be16)sin.sin_port)); ret = -EINVAL; goto out; } if (o2nm_this_node() > node->nd_num) { mlog(ML_NOTICE, "unexpected connect attempted from a lower " "numbered node '%s' at " "%u.%u.%u.%u:%d with num %u\n", node->nd_name, NIPQUAD(sin.sin_addr.s_addr), ntohs((__force __be16)sin.sin_port), node->nd_num); ret = -EINVAL; goto out; } /* this happens all the time when the other node sees our heartbeat * and tries to connect before we see their heartbeat */ if (!o2hb_check_node_heartbeating_from_callback(node->nd_num)) { mlog(ML_CONN, "attempt to connect from node '%s' at " "%u.%u.%u.%u:%d but it isn't heartbeating\n", node->nd_name, NIPQUAD(sin.sin_addr.s_addr), ntohs((__force __be16)sin.sin_port)); ret = -EINVAL; goto out; } nn = o2net_nn_from_num(node->nd_num); spin_lock(&nn->nn_lock); if (nn->nn_sc) ret = -EBUSY; else ret = 0; spin_unlock(&nn->nn_lock); if (ret) { mlog(ML_NOTICE, "attempt to connect from node '%s' at " "%u.%u.%u.%u:%d but it already has an open connection\n", node->nd_name, NIPQUAD(sin.sin_addr.s_addr), ntohs((__force __be16)sin.sin_port)); goto out; } sc = sc_alloc(node); if (sc == NULL) { ret = -ENOMEM; goto out; } sc->sc_sock = new_sock; new_sock = NULL; spin_lock(&nn->nn_lock); o2net_set_nn_state(nn, sc, 0, 0); spin_unlock(&nn->nn_lock); o2net_register_callbacks(sc->sc_sock->sk, sc); o2net_sc_queue_work(sc, &sc->sc_rx_work); o2net_sendpage(sc, o2net_hand, sizeof(*o2net_hand)); out: if (new_sock) sock_release(new_sock); if (node) o2nm_node_put(node); if (sc) sc_put(sc); return ret; } static void o2net_accept_many(void *arg) { struct socket *sock = arg; while (o2net_accept_one(sock) == 0) cond_resched(); } static void o2net_listen_data_ready(struct sock *sk, int bytes) { void (*ready)(struct sock *sk, int bytes); read_lock(&sk->sk_callback_lock); ready = sk->sk_user_data; if (ready == NULL) { /* check for teardown race */ ready = sk->sk_data_ready; goto out; } /* ->sk_data_ready is also called for a newly established child socket * before it has been accepted and the acceptor has set up their * data_ready.. we only want to queue listen work for our listening * socket */ if (sk->sk_state == TCP_LISTEN) { mlog(ML_TCP, "bytes: %d\n", bytes); queue_work(o2net_wq, &o2net_listen_work); } out: read_unlock(&sk->sk_callback_lock); ready(sk, bytes); } static int o2net_open_listening_sock(__be16 port) { struct socket *sock = NULL; int ret; struct sockaddr_in sin = { .sin_family = PF_INET, .sin_addr = { .s_addr = (__force u32)htonl(INADDR_ANY) }, .sin_port = (__force u16)port, }; ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock); if (ret < 0) { mlog(ML_ERROR, "unable to create socket, ret=%d\n", ret); goto out; } sock->sk->sk_allocation = GFP_ATOMIC; write_lock_bh(&sock->sk->sk_callback_lock); sock->sk->sk_user_data = sock->sk->sk_data_ready; sock->sk->sk_data_ready = o2net_listen_data_ready; write_unlock_bh(&sock->sk->sk_callback_lock); o2net_listen_sock = sock; INIT_WORK(&o2net_listen_work, o2net_accept_many, sock); sock->sk->sk_reuse = 1; ret = sock->ops->bind(sock, (struct sockaddr *)&sin, sizeof(sin)); if (ret < 0) { mlog(ML_ERROR, "unable to bind socket to port %d, ret=%d\n", ntohs(port), ret); goto out; } ret = sock->ops->listen(sock, 64); if (ret < 0) { mlog(ML_ERROR, "unable to listen on port %d, ret=%d\n", ntohs(port), ret); } out: if (ret) { o2net_listen_sock = NULL; if (sock) sock_release(sock); } return ret; } /* * called from node manager when we should bring up our network listening * socket. node manager handles all the serialization to only call this * once and to match it with o2net_stop_listening(). note, * o2nm_this_node() doesn't work yet as we're being called while it * is being set up. */ int o2net_start_listening(struct o2nm_node *node) { int ret = 0; BUG_ON(o2net_wq != NULL); BUG_ON(o2net_listen_sock != NULL); mlog(ML_KTHREAD, "starting o2net thread...\n"); o2net_wq = create_singlethread_workqueue("o2net"); if (o2net_wq == NULL) { mlog(ML_ERROR, "unable to launch o2net thread\n"); return -ENOMEM; /* ? */ } ret = o2net_open_listening_sock(node->nd_ipv4_port); if (ret) { destroy_workqueue(o2net_wq); o2net_wq = NULL; } else o2quo_conn_up(node->nd_num); return ret; } /* again, o2nm_this_node() doesn't work here as we're involved in * tearing it down */ void o2net_stop_listening(struct o2nm_node *node) { struct socket *sock = o2net_listen_sock; size_t i; BUG_ON(o2net_wq == NULL); BUG_ON(o2net_listen_sock == NULL); /* stop the listening socket from generating work */ write_lock_bh(&sock->sk->sk_callback_lock); sock->sk->sk_data_ready = sock->sk->sk_user_data; sock->sk->sk_user_data = NULL; write_unlock_bh(&sock->sk->sk_callback_lock); for (i = 0; i < ARRAY_SIZE(o2net_nodes); i++) { struct o2nm_node *node = o2nm_get_node_by_num(i); if (node) { o2net_disconnect_node(node); o2nm_node_put(node); } } /* finish all work and tear down the work queue */ mlog(ML_KTHREAD, "waiting for o2net thread to exit....\n"); destroy_workqueue(o2net_wq); o2net_wq = NULL; sock_release(o2net_listen_sock); o2net_listen_sock = NULL; o2quo_conn_err(node->nd_num); } /* ------------------------------------------------------------ */ int o2net_init(void) { unsigned long i; o2quo_init(); o2net_hand = kcalloc(1, sizeof(struct o2net_handshake), GFP_KERNEL); o2net_keep_req = kcalloc(1, sizeof(struct o2net_msg), GFP_KERNEL); o2net_keep_resp = kcalloc(1, sizeof(struct o2net_msg), GFP_KERNEL); if (!o2net_hand || !o2net_keep_req || !o2net_keep_resp) { kfree(o2net_hand); kfree(o2net_keep_req); kfree(o2net_keep_resp); return -ENOMEM; } o2net_hand->protocol_version = cpu_to_be64(O2NET_PROTOCOL_VERSION); o2net_hand->connector_id = cpu_to_be64(1); o2net_keep_req->magic = cpu_to_be16(O2NET_MSG_KEEP_REQ_MAGIC); o2net_keep_resp->magic = cpu_to_be16(O2NET_MSG_KEEP_RESP_MAGIC); for (i = 0; i < ARRAY_SIZE(o2net_nodes); i++) { struct o2net_node *nn = o2net_nn_from_num(i); spin_lock_init(&nn->nn_lock); INIT_WORK(&nn->nn_connect_work, o2net_start_connect, nn); INIT_WORK(&nn->nn_connect_expired, o2net_connect_expired, nn); INIT_WORK(&nn->nn_still_up, o2net_still_up, nn); /* until we see hb from a node we'll return einval */ nn->nn_persistent_error = -ENOTCONN; init_waitqueue_head(&nn->nn_sc_wq); idr_init(&nn->nn_status_idr); INIT_LIST_HEAD(&nn->nn_status_list); } return 0; } void o2net_exit(void) { o2quo_exit(); kfree(o2net_hand); kfree(o2net_keep_req); kfree(o2net_keep_resp); }