diff options
author | Zach Brown <zach.brown@oracle.com> | 2005-12-15 14:31:23 -0800 |
---|---|---|
committer | Joel Becker <joel.becker@oracle.com> | 2006-01-03 11:45:46 -0800 |
commit | 98211489d4147e41b11703e4245846d60b3acce4 (patch) | |
tree | f3c9c6b8df5bb001db79bc6314d8cbb5e127b45b /fs/ocfs2/cluster | |
parent | a7f6a5fb4bde142b622706e2006ba33f793e13ed (diff) |
[PATCH] OCFS2: The Second Oracle Cluster Filesystem
Node messaging via tcp. Used by the dlm and the file system for point
to point communication between nodes.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>
Diffstat (limited to 'fs/ocfs2/cluster')
-rw-r--r-- | fs/ocfs2/cluster/quorum.c | 315 | ||||
-rw-r--r-- | fs/ocfs2/cluster/quorum.h | 36 | ||||
-rw-r--r-- | fs/ocfs2/cluster/sys.c | 124 | ||||
-rw-r--r-- | fs/ocfs2/cluster/sys.h | 33 | ||||
-rw-r--r-- | fs/ocfs2/cluster/tcp.c | 1829 | ||||
-rw-r--r-- | fs/ocfs2/cluster/tcp.h | 113 | ||||
-rw-r--r-- | fs/ocfs2/cluster/tcp_internal.h | 174 |
7 files changed, 2624 insertions, 0 deletions
diff --git a/fs/ocfs2/cluster/quorum.c b/fs/ocfs2/cluster/quorum.c new file mode 100644 index 000000000000..7bba98fbfc15 --- /dev/null +++ b/fs/ocfs2/cluster/quorum.c @@ -0,0 +1,315 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * Copyright (C) 2005 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. + */ + +/* This quorum hack is only here until we transition to some more rational + * approach that is driven from userspace. Honest. No foolin'. + * + * Imagine two nodes lose network connectivity to each other but they're still + * up and operating in every other way. Presumably a network timeout indicates + * that a node is broken and should be recovered. They can't both recover each + * other and both carry on without serialising their access to the file system. + * They need to decide who is authoritative. Now extend that problem to + * arbitrary groups of nodes losing connectivity between each other. + * + * So we declare that a node which has given up on connecting to a majority + * of nodes who are still heartbeating will fence itself. + * + * There are huge opportunities for races here. After we give up on a node's + * connection we need to wait long enough to give heartbeat an opportunity + * to declare the node as truly dead. We also need to be careful with the + * race between when we see a node start heartbeating and when we connect + * to it. + * + * So nodes that are in this transtion put a hold on the quorum decision + * with a counter. As they fall out of this transition they drop the count + * and if they're the last, they fire off the decision. + */ +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/workqueue.h> + +#include "heartbeat.h" +#include "nodemanager.h" +#define MLOG_MASK_PREFIX ML_QUORUM +#include "masklog.h" +#include "quorum.h" + +static struct o2quo_state { + spinlock_t qs_lock; + struct work_struct qs_work; + int qs_pending; + int qs_heartbeating; + unsigned long qs_hb_bm[BITS_TO_LONGS(O2NM_MAX_NODES)]; + int qs_connected; + unsigned long qs_conn_bm[BITS_TO_LONGS(O2NM_MAX_NODES)]; + int qs_holds; + unsigned long qs_hold_bm[BITS_TO_LONGS(O2NM_MAX_NODES)]; +} o2quo_state; + +/* this is horribly heavy-handed. It should instead flip the file + * system RO and call some userspace script. */ +static void o2quo_fence_self(void) +{ + /* panic spins with interrupts enabled. with preempt + * threads can still schedule, etc, etc */ + o2hb_stop_all_regions(); + panic("ocfs2 is very sorry to be fencing this system by panicing\n"); +} + +/* Indicate that a timeout occured on a hearbeat region write. The + * other nodes in the cluster may consider us dead at that time so we + * want to "fence" ourselves so that we don't scribble on the disk + * after they think they've recovered us. This can't solve all + * problems related to writeout after recovery but this hack can at + * least close some of those gaps. When we have real fencing, this can + * go away as our node would be fenced externally before other nodes + * begin recovery. */ +void o2quo_disk_timeout(void) +{ + o2quo_fence_self(); +} + +static void o2quo_make_decision(void *arg) +{ + int quorum; + int lowest_hb, lowest_reachable = 0, fence = 0; + struct o2quo_state *qs = &o2quo_state; + + spin_lock(&qs->qs_lock); + + lowest_hb = find_first_bit(qs->qs_hb_bm, O2NM_MAX_NODES); + if (lowest_hb != O2NM_MAX_NODES) + lowest_reachable = test_bit(lowest_hb, qs->qs_conn_bm); + + mlog(0, "heartbeating: %d, connected: %d, " + "lowest: %d (%sreachable)\n", qs->qs_heartbeating, + qs->qs_connected, lowest_hb, lowest_reachable ? "" : "un"); + + if (!test_bit(o2nm_this_node(), qs->qs_hb_bm) || + qs->qs_heartbeating == 1) + goto out; + + if (qs->qs_heartbeating & 1) { + /* the odd numbered cluster case is straight forward -- + * if we can't talk to the majority we're hosed */ + quorum = (qs->qs_heartbeating + 1)/2; + if (qs->qs_connected < quorum) { + mlog(ML_ERROR, "fencing this node because it is " + "only connected to %u nodes and %u is needed " + "to make a quorum out of %u heartbeating nodes\n", + qs->qs_connected, quorum, + qs->qs_heartbeating); + fence = 1; + } + } else { + /* the even numbered cluster adds the possibility of each half + * of the cluster being able to talk amongst themselves.. in + * that case we're hosed if we can't talk to the group that has + * the lowest numbered node */ + quorum = qs->qs_heartbeating / 2; + if (qs->qs_connected < quorum) { + mlog(ML_ERROR, "fencing this node because it is " + "only connected to %u nodes and %u is needed " + "to make a quorum out of %u heartbeating nodes\n", + qs->qs_connected, quorum, + qs->qs_heartbeating); + fence = 1; + } + else if ((qs->qs_connected == quorum) && + !lowest_reachable) { + mlog(ML_ERROR, "fencing this node because it is " + "connected to a half-quorum of %u out of %u " + "nodes which doesn't include the lowest active " + "node %u\n", quorum, qs->qs_heartbeating, + lowest_hb); + fence = 1; + } + } + +out: + spin_unlock(&qs->qs_lock); + if (fence) + o2quo_fence_self(); +} + +static void o2quo_set_hold(struct o2quo_state *qs, u8 node) +{ + assert_spin_locked(&qs->qs_lock); + + if (!test_and_set_bit(node, qs->qs_hold_bm)) { + qs->qs_holds++; + mlog_bug_on_msg(qs->qs_holds == O2NM_MAX_NODES, + "node %u\n", node); + mlog(0, "node %u, %d total\n", node, qs->qs_holds); + } +} + +static void o2quo_clear_hold(struct o2quo_state *qs, u8 node) +{ + assert_spin_locked(&qs->qs_lock); + + if (test_and_clear_bit(node, qs->qs_hold_bm)) { + mlog(0, "node %u, %d total\n", node, qs->qs_holds - 1); + if (--qs->qs_holds == 0) { + if (qs->qs_pending) { + qs->qs_pending = 0; + schedule_work(&qs->qs_work); + } + } + mlog_bug_on_msg(qs->qs_holds < 0, "node %u, holds %d\n", + node, qs->qs_holds); + } +} + +/* as a node comes up we delay the quorum decision until we know the fate of + * the connection. the hold will be droped in conn_up or hb_down. it might be + * perpetuated by con_err until hb_down. if we already have a conn, we might + * be dropping a hold that conn_up got. */ +void o2quo_hb_up(u8 node) +{ + struct o2quo_state *qs = &o2quo_state; + + spin_lock(&qs->qs_lock); + + qs->qs_heartbeating++; + mlog_bug_on_msg(qs->qs_heartbeating == O2NM_MAX_NODES, + "node %u\n", node); + mlog_bug_on_msg(test_bit(node, qs->qs_hb_bm), "node %u\n", node); + set_bit(node, qs->qs_hb_bm); + + mlog(0, "node %u, %d total\n", node, qs->qs_heartbeating); + + if (!test_bit(node, qs->qs_conn_bm)) + o2quo_set_hold(qs, node); + else + o2quo_clear_hold(qs, node); + + spin_unlock(&qs->qs_lock); +} + +/* hb going down releases any holds we might have had due to this node from + * conn_up, conn_err, or hb_up */ +void o2quo_hb_down(u8 node) +{ + struct o2quo_state *qs = &o2quo_state; + + spin_lock(&qs->qs_lock); + + qs->qs_heartbeating--; + mlog_bug_on_msg(qs->qs_heartbeating < 0, + "node %u, %d heartbeating\n", + node, qs->qs_heartbeating); + mlog_bug_on_msg(!test_bit(node, qs->qs_hb_bm), "node %u\n", node); + clear_bit(node, qs->qs_hb_bm); + + mlog(0, "node %u, %d total\n", node, qs->qs_heartbeating); + + o2quo_clear_hold(qs, node); + + spin_unlock(&qs->qs_lock); +} + +/* this tells us that we've decided that the node is still heartbeating + * even though we've lost it's conn. it must only be called after conn_err + * and indicates that we must now make a quorum decision in the future, + * though we might be doing so after waiting for holds to drain. Here + * we'll be dropping the hold from conn_err. */ +void o2quo_hb_still_up(u8 node) +{ + struct o2quo_state *qs = &o2quo_state; + + spin_lock(&qs->qs_lock); + + mlog(0, "node %u\n", node); + + qs->qs_pending = 1; + o2quo_clear_hold(qs, node); + + spin_unlock(&qs->qs_lock); +} + +/* This is analagous to hb_up. as a node's connection comes up we delay the + * quorum decision until we see it heartbeating. the hold will be droped in + * hb_up or hb_down. it might be perpetuated by con_err until hb_down. if + * it's already heartbeating we we might be dropping a hold that conn_up got. + * */ +void o2quo_conn_up(u8 node) +{ + struct o2quo_state *qs = &o2quo_state; + + spin_lock(&qs->qs_lock); + + qs->qs_connected++; + mlog_bug_on_msg(qs->qs_connected == O2NM_MAX_NODES, + "node %u\n", node); + mlog_bug_on_msg(test_bit(node, qs->qs_conn_bm), "node %u\n", node); + set_bit(node, qs->qs_conn_bm); + + mlog(0, "node %u, %d total\n", node, qs->qs_connected); + + if (!test_bit(node, qs->qs_hb_bm)) + o2quo_set_hold(qs, node); + else + o2quo_clear_hold(qs, node); + + spin_unlock(&qs->qs_lock); +} + +/* we've decided that we won't ever be connecting to the node again. if it's + * still heartbeating we grab a hold that will delay decisions until either the + * node stops heartbeating from hb_down or the caller decides that the node is + * still up and calls still_up */ +void o2quo_conn_err(u8 node) +{ + struct o2quo_state *qs = &o2quo_state; + + spin_lock(&qs->qs_lock); + + if (test_bit(node, qs->qs_conn_bm)) { + qs->qs_connected--; + mlog_bug_on_msg(qs->qs_connected < 0, + "node %u, connected %d\n", + node, qs->qs_connected); + + clear_bit(node, qs->qs_conn_bm); + } + + mlog(0, "node %u, %d total\n", node, qs->qs_connected); + + if (test_bit(node, qs->qs_hb_bm)) + o2quo_set_hold(qs, node); + + spin_unlock(&qs->qs_lock); +} + +void o2quo_init(void) +{ + struct o2quo_state *qs = &o2quo_state; + + spin_lock_init(&qs->qs_lock); + INIT_WORK(&qs->qs_work, o2quo_make_decision, NULL); +} + +void o2quo_exit(void) +{ + flush_scheduled_work(); +} diff --git a/fs/ocfs2/cluster/quorum.h b/fs/ocfs2/cluster/quorum.h new file mode 100644 index 000000000000..6649cc6f67c9 --- /dev/null +++ b/fs/ocfs2/cluster/quorum.h @@ -0,0 +1,36 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * Copyright (C) 2005 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. + * + */ + +#ifndef O2CLUSTER_QUORUM_H +#define O2CLUSTER_QUORUM_H + +void o2quo_init(void); +void o2quo_exit(void); + +void o2quo_hb_up(u8 node); +void o2quo_hb_down(u8 node); +void o2quo_hb_still_up(u8 node); +void o2quo_conn_up(u8 node); +void o2quo_conn_err(u8 node); +void o2quo_disk_timeout(void); + +#endif /* O2CLUSTER_QUORUM_H */ diff --git a/fs/ocfs2/cluster/sys.c b/fs/ocfs2/cluster/sys.c new file mode 100644 index 000000000000..f1e99461bb0d --- /dev/null +++ b/fs/ocfs2/cluster/sys.c @@ -0,0 +1,124 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * sys.c + * + * OCFS2 cluster sysfs interface + * + * Copyright (C) 2005 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, + * version 2 of the License. + * + * 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. + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/kobject.h> +#include <linux/sysfs.h> + +#include "ocfs2_nodemanager.h" +#include "masklog.h" +#include "sys.h" + +struct o2cb_attribute { + struct attribute attr; + ssize_t (*show)(char *buf); + ssize_t (*store)(const char *buf, size_t count); +}; + +#define O2CB_ATTR(_name, _mode, _show, _store) \ +struct o2cb_attribute o2cb_attr_##_name = __ATTR(_name, _mode, _show, _store) + +#define to_o2cb_subsys(k) container_of(to_kset(k), struct subsystem, kset) +#define to_o2cb_attr(_attr) container_of(_attr, struct o2cb_attribute, attr) + +static ssize_t o2cb_interface_revision_show(char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%u\n", O2NM_API_VERSION); +} + +O2CB_ATTR(interface_revision, S_IFREG | S_IRUGO, o2cb_interface_revision_show, NULL); + +static struct attribute *o2cb_attrs[] = { + &o2cb_attr_interface_revision.attr, + NULL, +}; + +static ssize_t +o2cb_show(struct kobject * kobj, struct attribute * attr, char * buffer); +static ssize_t +o2cb_store(struct kobject * kobj, struct attribute * attr, + const char * buffer, size_t count); +static struct sysfs_ops o2cb_sysfs_ops = { + .show = o2cb_show, + .store = o2cb_store, +}; + +static struct kobj_type o2cb_subsys_type = { + .default_attrs = o2cb_attrs, + .sysfs_ops = &o2cb_sysfs_ops, +}; + +/* gives us o2cb_subsys */ +decl_subsys(o2cb, NULL, NULL); + +static ssize_t +o2cb_show(struct kobject * kobj, struct attribute * attr, char * buffer) +{ + struct o2cb_attribute *o2cb_attr = to_o2cb_attr(attr); + struct subsystem *sbs = to_o2cb_subsys(kobj); + + BUG_ON(sbs != &o2cb_subsys); + + if (o2cb_attr->show) + return o2cb_attr->show(buffer); + return -EIO; +} + +static ssize_t +o2cb_store(struct kobject * kobj, struct attribute * attr, + const char * buffer, size_t count) +{ + struct o2cb_attribute *o2cb_attr = to_o2cb_attr(attr); + struct subsystem *sbs = to_o2cb_subsys(kobj); + + BUG_ON(sbs != &o2cb_subsys); + + if (o2cb_attr->store) + return o2cb_attr->store(buffer, count); + return -EIO; +} + +void o2cb_sys_shutdown(void) +{ + mlog_sys_shutdown(); + subsystem_unregister(&o2cb_subsys); +} + +int o2cb_sys_init(void) +{ + int ret; + + o2cb_subsys.kset.kobj.ktype = &o2cb_subsys_type; + ret = subsystem_register(&o2cb_subsys); + if (ret) + return ret; + + ret = mlog_sys_init(&o2cb_subsys); + if (ret) + subsystem_unregister(&o2cb_subsys); + return ret; +} diff --git a/fs/ocfs2/cluster/sys.h b/fs/ocfs2/cluster/sys.h new file mode 100644 index 000000000000..d66b8ab0045e --- /dev/null +++ b/fs/ocfs2/cluster/sys.h @@ -0,0 +1,33 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * sys.h + * + * Function prototypes for o2cb sysfs interface + * + * Copyright (C) 2005 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, + * version 2 of the License. + * + * 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. + * + */ + +#ifndef O2CLUSTER_SYS_H +#define O2CLUSTER_SYS_H + +void o2cb_sys_shutdown(void); +int o2cb_sys_init(void); + +#endif /* O2CLUSTER_SYS_H */ diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c new file mode 100644 index 000000000000..35d92c01a972 --- /dev/null +++ b/fs/ocfs2/cluster/tcp.c @@ -0,0 +1,1829 @@ +/* -*- 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 rwlock_t o2net_handler_lock = RW_LOCK_UNLOCKED; +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 TC |