fs/ocfs2/cluster/tcp_internal.h

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * Copyright (C) 2005 Oracle.  All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public
  17  * License along with this program; if not, write to the
  18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19  * Boston, MA 021110-1307, USA.
  20  */
  21
  22 #ifndef O2CLUSTER_TCP_INTERNAL_H
  23 #define O2CLUSTER_TCP_INTERNAL_H
  24
  25 #define O2NET_MSG_MAGIC           ((u16)0xfa55)
  26 #define O2NET_MSG_STATUS_MAGIC    ((u16)0xfa56)
  27 #define O2NET_MSG_KEEP_REQ_MAGIC  ((u16)0xfa57)
  28 #define O2NET_MSG_KEEP_RESP_MAGIC ((u16)0xfa58)
  29
  30 /* same as hb delay, we're waiting for another node to recognize our hb */
  31 #define O2NET_RECONNECT_DELAY_MS        O2HB_REGION_TIMEOUT_MS
  32
  33 /* we're delaying our quorum decision so that heartbeat will have timed
  34  * out truly dead nodes by the time we come around to making decisions
  35  * on their number */
  36 #define O2NET_QUORUM_DELAY_MS   ((o2hb_dead_threshold + 2) * O2HB_REGION_TIMEOUT_MS)
  37
  38 #define O2NET_KEEPALIVE_DELAY_SECS      5
  39 #define O2NET_IDLE_TIMEOUT_SECS         10
  40
  41 /*
  42  * This version number represents quite a lot, unfortunately.  It not
  43  * only represents the raw network message protocol on the wire but also
  44  * locking semantics of the file system using the protocol.  It should
  45  * be somewhere else, I'm sure, but right now it isn't.
  46  *
  47  * New in version 4:
  48  *      - Remove i_generation from lock names for better stat performance.
  49  *
  50  * New in version 3:
  51  *      - Replace dentry votes with a cluster lock
  52  *
  53  * New in version 2:
  54  *      - full 64 bit i_size in the metadata lock lvbs
  55  *      - introduction of "rw" lock and pushing meta/data locking down
  56  */
  57 #define O2NET_PROTOCOL_VERSION 4ULL
  58 struct o2net_handshake {
  59         __be64  protocol_version;
  60         __be64  connector_id;
  61 };
  62
  63 struct o2net_node {
  64         /* this is never called from int/bh */
  65         spinlock_t                      nn_lock;
  66
  67         /* set the moment an sc is allocated and a connect is started */
  68         struct o2net_sock_container     *nn_sc;
  69         /* _valid is only set after the handshake passes and tx can happen */
  70         unsigned                        nn_sc_valid:1;
  71         /* if this is set tx just returns it */
  72         int                             nn_persistent_error;
  73
  74         /* threads waiting for an sc to arrive wait on the wq for generation
  75          * to increase.  it is increased when a connecting socket succeeds
  76          * or fails or when an accepted socket is attached. */
  77         wait_queue_head_t               nn_sc_wq;
  78
  79         struct idr                      nn_status_idr;
  80         struct list_head                nn_status_list;
  81
  82         /* connects are attempted from when heartbeat comes up until either hb
  83          * goes down, the node is unconfigured, no connect attempts succeed
  84          * before O2NET_CONN_IDLE_DELAY, or a connect succeeds.  connect_work
  85          * is queued from set_nn_state both from hb up and from itself if a
  86          * connect attempt fails and so can be self-arming.  shutdown is
  87          * careful to first mark the nn such that no connects will be attempted
  88          * before canceling delayed connect work and flushing the queue. */
  89         struct work_struct              nn_connect_work;
  90         unsigned long                   nn_last_connect_attempt;
  91
  92         /* this is queued as nodes come up and is canceled when a connection is
  93          * established.  this expiring gives up on the node and errors out
  94          * transmits */
  95         struct work_struct              nn_connect_expired;
  96
  97         /* after we give up on a socket we wait a while before deciding
  98          * that it is still heartbeating and that we should do some
  99          * quorum work */
 100         struct work_struct              nn_still_up;
 101 };
 102
 103 struct o2net_sock_container {
 104         struct kref             sc_kref;
 105         /* the next two are vaild for the life time of the sc */
 106         struct socket           *sc_sock;
 107         struct o2nm_node        *sc_node;
 108
 109         /* all of these sc work structs hold refs on the sc while they are
 110          * queued.  they should not be able to ref a freed sc.  the teardown
 111          * race is with o2net_wq destruction in o2net_stop_listening() */
 112
 113         /* rx and connect work are generated from socket callbacks.  sc
 114          * shutdown removes the callbacks and then flushes the work queue */
 115         struct work_struct      sc_rx_work;
 116         struct work_struct      sc_connect_work;
 117         /* shutdown work is triggered in two ways.  the simple way is
 118          * for a code path calls ensure_shutdown which gets a lock, removes
 119          * the sc from the nn, and queues the work.  in this case the
 120          * work is single-shot.  the work is also queued from a sock
 121          * callback, though, and in this case the work will find the sc
 122          * still on the nn and will call ensure_shutdown itself.. this
 123          * ends up triggering the shutdown work again, though nothing
 124          * will be done in that second iteration.  so work queue teardown
 125          * has to be careful to remove the sc from the nn before waiting
 126          * on the work queue so that the shutdown work doesn't remove the
 127          * sc and rearm itself.
 128          */
 129         struct work_struct      sc_shutdown_work;
 130
 131         struct timer_list       sc_idle_timeout;
 132         struct work_struct      sc_keepalive_work;
 133
 134         unsigned                sc_handshake_ok:1;
 135
 136         struct page             *sc_page;
 137         size_t                  sc_page_off;
 138
 139         /* original handlers for the sockets */
 140         void                    (*sc_state_change)(struct sock *sk);
 141         void                    (*sc_data_ready)(struct sock *sk, int bytes);
 142
 143         struct timeval          sc_tv_timer;
 144         struct timeval          sc_tv_data_ready;
 145         struct timeval          sc_tv_advance_start;
 146         struct timeval          sc_tv_advance_stop;
 147         struct timeval          sc_tv_func_start;
 148         struct timeval          sc_tv_func_stop;
 149         u32                     sc_msg_key;
 150         u16                     sc_msg_type;
 151 };
 152
 153 struct o2net_msg_handler {
 154         struct rb_node          nh_node;
 155         u32                     nh_max_len;
 156         u32                     nh_msg_type;
 157         u32                     nh_key;
 158         o2net_msg_handler_func  *nh_func;
 159         o2net_msg_handler_func  *nh_func_data;
 160         struct kref             nh_kref;
 161         struct list_head        nh_unregister_item;
 162 };
 163
 164 enum o2net_system_error {
 165         O2NET_ERR_NONE = 0,
 166         O2NET_ERR_NO_HNDLR,
 167         O2NET_ERR_OVERFLOW,
 168         O2NET_ERR_DIED,
 169         O2NET_ERR_MAX
 170 };
 171
 172 struct o2net_status_wait {
 173         enum o2net_system_error ns_sys_status;
 174         s32                     ns_status;
 175         int                     ns_id;
 176         wait_queue_head_t       ns_wq;
 177         struct list_head        ns_node_item;
 178 };
 179
 180 #endif /* O2CLUSTER_TCP_INTERNAL_H */