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 #ifdef __KERNEL__
  25 #include <linux/obd_support.h>
  26 #include <linux/obd_class.h>
  27 #include <linux/lustre_net.h>
  28 #else
  29 #include <liblustre.h>
  30 #endif
  31
  32 #include "ptlrpc_internal.h"
  33
  34 static spinlock_t conn_lock;
  35 static struct list_head conn_list;
  36 static struct list_head conn_unused_list;
  37
  38 void ptlrpc_dump_connections(void)
  39 {
  40         struct list_head *tmp;
  41         struct ptlrpc_connection *c;
  42         ENTRY;
  43
  44         list_for_each(tmp, &conn_list) {
  45                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  46                 CERROR("Connection %p/%s has refcount %d (nid="LPX64" on %s)\n",
  47                        c, c->c_remote_uuid.uuid, atomic_read(&c->c_refcount),
  48                        c->c_peer.peer_nid, c->c_peer.peer_ni->pni_name);
  49         }
  50         EXIT;
  51 }
  52
  53 struct ptlrpc_connection *ptlrpc_get_connection(struct ptlrpc_peer *peer,
  54                                                 struct obd_uuid *uuid)
  55 {
  56         struct list_head *tmp, *pos;
  57         struct ptlrpc_connection *c;
  58         ENTRY;
  59
  60
  61         CDEBUG(D_INFO, "peer is "LPX64" on %s\n",
  62                peer->peer_nid, peer->peer_ni->pni_name);
  63
  64         spin_lock(&conn_lock);
  65         list_for_each(tmp, &conn_list) {
  66                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  67                 if (peer->peer_nid == c->c_peer.peer_nid &&
  68                     peer->peer_ni == c->c_peer.peer_ni) {
  69                         ptlrpc_connection_addref(c);
  70                         GOTO(out, c);
  71                 }
  72         }
  73
  74         list_for_each_safe(tmp, pos, &conn_unused_list) {
  75                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  76                 if (peer->peer_nid == c->c_peer.peer_nid &&
  77                     peer->peer_ni == c->c_peer.peer_ni) {
  78                         ptlrpc_connection_addref(c);
  79                         list_del(&c->c_link);
  80                         list_add(&c->c_link, &conn_list);
  81                         GOTO(out, c);
  82                 }
  83         }
  84
  85         /* FIXME: this should be a slab once we can validate slab addresses
  86          * without OOPSing */
  87         OBD_ALLOC(c, sizeof(*c));
  88         if (c == NULL)
  89                 GOTO(out, c);
  90
  91         if (uuid && uuid->uuid)                         /* XXX ???? */
  92                 obd_str2uuid(&c->c_remote_uuid, uuid->uuid);
  93         atomic_set(&c->c_refcount, 0);
  94         memcpy(&c->c_peer, peer, sizeof(c->c_peer));
  95
  96         ptlrpc_connection_addref(c);
  97
  98         list_add(&c->c_link, &conn_list);
  99
 100         EXIT;
 101  out:
 102         spin_unlock(&conn_lock);
 103         return c;
 104 }
 105
 106 int ptlrpc_put_connection(struct ptlrpc_connection *c)
 107 {
 108         int rc = 0;
 109         ENTRY;
 110
 111         if (c == NULL) {
 112                 CERROR("NULL connection\n");
 113                 RETURN(0);
 114         }
 115
 116         CDEBUG (D_INFO, "connection=%p refcount %d to "LPX64" on %s\n",
 117                 c, atomic_read(&c->c_refcount) - 1, c->c_peer.peer_nid,
 118                 c->c_peer.peer_ni->pni_name);
 119
 120         if (atomic_dec_and_test(&c->c_refcount)) {
 121                 spin_lock(&conn_lock);
 122                 list_del(&c->c_link);
 123                 list_add(&c->c_link, &conn_unused_list);
 124                 spin_unlock(&conn_lock);
 125                 rc = 1;
 126         }
 127         if (atomic_read(&c->c_refcount) < 0)
 128                 CERROR("connection %p refcount %d!\n",
 129                        c, atomic_read(&c->c_refcount));
 130
 131         RETURN(rc);
 132 }
 133
 134 struct ptlrpc_connection *ptlrpc_connection_addref(struct ptlrpc_connection *c)
 135 {
 136         ENTRY;
 137         atomic_inc(&c->c_refcount);
 138         CDEBUG (D_INFO, "connection=%p refcount %d to "LPX64" on %s\n",
 139                 c, atomic_read(&c->c_refcount), c->c_peer.peer_nid,
 140                 c->c_peer.peer_ni->pni_name);
 141         RETURN(c);
 142 }
 143
 144 void ptlrpc_init_connection(void)
 145 {
 146         INIT_LIST_HEAD(&conn_list);
 147         INIT_LIST_HEAD(&conn_unused_list);
 148         conn_lock = SPIN_LOCK_UNLOCKED;
 149 }
 150
 151 void ptlrpc_cleanup_connection(void)
 152 {
 153         struct list_head *tmp, *pos;
 154         struct ptlrpc_connection *c;
 155
 156         spin_lock(&conn_lock);
 157         list_for_each_safe(tmp, pos, &conn_unused_list) {
 158                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
 159                 list_del(&c->c_link);
 160                 OBD_FREE(c, sizeof(*c));
 161         }
 162         list_for_each_safe(tmp, pos, &conn_list) {
 163                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
 164                 CERROR("Connection %p/%s has refcount %d (nid="LPX64" on %s)\n",
 165                        c, c->c_remote_uuid.uuid, atomic_read(&c->c_refcount),
 166                        c->c_peer.peer_nid, c->c_peer.peer_ni->pni_name);
 167                 list_del(&c->c_link);
 168                 OBD_FREE(c, sizeof(*c));
 169         }
 170         spin_unlock(&conn_lock);
 171 }