lustre/ptlrpc/connection.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (C) 2002 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of Lustre, http://www.lustre.org.
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  */
  22
  23 #define DEBUG_SUBSYSTEM S_RPC
  24
  25 #include <linux/obd_support.h>
  26 #include <linux/lustre_net.h>
  27
  28 static spinlock_t conn_lock;
  29 static struct list_head conn_list;
  30 static struct list_head conn_unused_list;
  31
  32 struct ptlrpc_connection *ptlrpc_get_connection(struct lustre_peer *peer,
  33                                                 char *uuid)
  34 {
  35         struct list_head *tmp, *pos;
  36         struct ptlrpc_connection *c;
  37         ENTRY;
  38
  39         CDEBUG(D_INFO, "peer is %08x %08lx %08lx\n",
  40                peer->peer_nid, peer->peer_ni.nal_idx, peer->peer_ni.handle_idx);
  41
  42         spin_lock(&conn_lock);
  43         list_for_each(tmp, &conn_list) {
  44                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  45                 if (memcmp(peer, &c->c_peer, sizeof(*peer)) == 0 &&
  46                     (!uuid || strcmp(c->c_remote_uuid, uuid) == 0)) {
  47                         ptlrpc_connection_addref(c);
  48                         GOTO(out, c);
  49                 }
  50         }
  51
  52         list_for_each_safe(tmp, pos, &conn_unused_list) {
  53                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  54                 if (memcmp(peer, &c->c_peer, sizeof(*peer)) == 0 &&
  55                     (!uuid || strcmp(c->c_remote_uuid, uuid) == 0)) {
  56                         ptlrpc_connection_addref(c);
  57                         list_del(&c->c_link);
  58                         list_add(&c->c_link, &conn_list);
  59                         GOTO(out, c);
  60                 }
  61         }
  62
  63         /* FIXME: this should be a slab once we can validate slab addresses
  64          * without OOPSing */
  65         OBD_ALLOC(c, sizeof(*c));
  66         if (c == NULL)
  67                 GOTO(out, c);
  68
  69         c->c_level = LUSTRE_CONN_NEW;
  70         c->c_xid_in = 1;
  71         c->c_xid_out = 1;
  72         c->c_generation = 1;
  73         c->c_epoch = 1;
  74         c->c_bootcount = 0;
  75         strcpy(c->c_remote_uuid, uuid);
  76         INIT_LIST_HEAD(&c->c_delayed_head);
  77         INIT_LIST_HEAD(&c->c_sending_head);
  78         INIT_LIST_HEAD(&c->c_dying_head);
  79         INIT_LIST_HEAD(&c->c_clients);
  80         INIT_LIST_HEAD(&c->c_exports);
  81         atomic_set(&c->c_refcount, 0);
  82         ptlrpc_connection_addref(c);
  83         spin_lock_init(&c->c_lock);
  84
  85         memcpy(&c->c_peer, peer, sizeof(c->c_peer));
  86         list_add(&c->c_link, &conn_list);
  87
  88         EXIT;
  89  out:
  90         spin_unlock(&conn_lock);
  91         return c;
  92 }
  93
  94 int ptlrpc_put_connection(struct ptlrpc_connection *c)
  95 {
  96         int rc = 0;
  97         ENTRY;
  98
  99         CDEBUG(D_INFO, "connection=%p refcount %d\n",
 100                c, atomic_read(&c->c_refcount) - 1);
 101         if (atomic_dec_and_test(&c->c_refcount)) {
 102                 spin_lock(&conn_lock);
 103                 list_del(&c->c_link);
 104                 list_add(&c->c_link, &conn_unused_list);
 105                 spin_unlock(&conn_lock);
 106                 rc = 1;
 107         }
 108         if (atomic_read(&c->c_refcount) < 0)
 109                 CERROR("connection %p refcount %d!\n",
 110                        c, atomic_read(&c->c_refcount));
 111
 112         RETURN(rc);
 113 }
 114
 115 struct ptlrpc_connection *ptlrpc_connection_addref(struct ptlrpc_connection *c)
 116 {
 117         ENTRY;
 118         CDEBUG(D_INFO, "connection=%p refcount %d\n",
 119                c, atomic_read(&c->c_refcount) + 1);
 120         atomic_inc(&c->c_refcount);
 121         RETURN(c);
 122 }
 123
 124 void ptlrpc_init_connection(void)
 125 {
 126         INIT_LIST_HEAD(&conn_list);
 127         INIT_LIST_HEAD(&conn_unused_list);
 128         conn_lock = SPIN_LOCK_UNLOCKED;
 129 }
 130
 131 void ptlrpc_cleanup_connection(void)
 132 {
 133         struct list_head *tmp, *pos;
 134         struct ptlrpc_connection *c;
 135
 136         spin_lock(&conn_lock);
 137         list_for_each_safe(tmp, pos, &conn_unused_list) {
 138                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
 139                 list_del(&c->c_link);
 140                 OBD_FREE(c, sizeof(*c));
 141         }
 142         list_for_each_safe(tmp, pos, &conn_list) {
 143                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
 144                 CERROR("Connection %p has refcount %d at cleanup (nid=%lu)!\n",
 145                        c, atomic_read(&c->c_refcount),
 146                        (unsigned long)c->c_peer.peer_nid);
 147                 list_del(&c->c_link);
 148                 OBD_FREE(c, sizeof(*c));
 149         }
 150         spin_unlock(&conn_lock);
 151 }