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=%s)\n",
  47                        c, c->c_remote_uuid.uuid, atomic_read(&c->c_refcount),
  48                        libcfs_nid2str(c->c_peer.nid));
  49         }
  50         EXIT;
  51 }
  52
  53 struct ptlrpc_connection *ptlrpc_get_connection(ptl_process_id_t peer,
  54                                                 struct obd_uuid *uuid)
  55 {
  56         struct list_head *tmp, *pos;
  57         struct ptlrpc_connection *c;
  58         ENTRY;
  59
  60         CDEBUG(D_INFO, "peer is %s\n", libcfs_id2str(peer));
  61
  62         spin_lock(&conn_lock);
  63         list_for_each(tmp, &conn_list) {
  64                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  65                 if (memcmp(&peer, &c->c_peer, sizeof(peer)) == 0) {
  66                         ptlrpc_connection_addref(c);
  67                         GOTO(out, c);
  68                 }
  69         }
  70
  71         list_for_each_safe(tmp, pos, &conn_unused_list) {
  72                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  73                 if (memcmp(&peer, &c->c_peer, sizeof(peer)) == 0) {
  74                         ptlrpc_connection_addref(c);
  75                         list_del(&c->c_link);
  76                         list_add(&c->c_link, &conn_list);
  77                         GOTO(out, c);
  78                 }
  79         }
  80
  81         /* FIXME: this should be a slab once we can validate slab addresses
  82          * without OOPSing */
  83         OBD_ALLOC_GFP(c, sizeof(*c), GFP_ATOMIC);
  84
  85         if (c == NULL)
  86                 GOTO(out, c);
  87
  88         if (uuid && uuid->uuid)                         /* XXX ???? */
  89                 obd_str2uuid(&c->c_remote_uuid, uuid->uuid);
  90         atomic_set(&c->c_refcount, 0);
  91         memcpy(&c->c_peer, &peer, sizeof(c->c_peer));
  92
  93         ptlrpc_connection_addref(c);
  94
  95         list_add(&c->c_link, &conn_list);
  96
  97         EXIT;
  98  out:
  99         spin_unlock(&conn_lock);
 100         return c;
 101 }
 102
 103 int ptlrpc_put_connection(struct ptlrpc_connection *c)
 104 {
 105         int rc = 0;
 106         ENTRY;
 107
 108         if (c == NULL) {
 109                 CERROR("NULL connection\n");
 110                 RETURN(0);
 111         }
 112
 113         CDEBUG (D_INFO, "connection=%p refcount %d to %s\n",
 114                 c, atomic_read(&c->c_refcount) - 1,
 115                 libcfs_nid2str(c->c_peer.nid));
 116
 117         if (atomic_dec_and_test(&c->c_refcount)) {
 118                 spin_lock(&conn_lock);
 119                 list_del(&c->c_link);
 120                 list_add(&c->c_link, &conn_unused_list);
 121                 spin_unlock(&conn_lock);
 122                 rc = 1;
 123         }
 124         if (atomic_read(&c->c_refcount) < 0)
 125                 CERROR("connection %p refcount %d!\n",
 126                        c, atomic_read(&c->c_refcount));
 127
 128         RETURN(rc);
 129 }
 130
 131 struct ptlrpc_connection *ptlrpc_connection_addref(struct ptlrpc_connection *c)
 132 {
 133         ENTRY;
 134         atomic_inc(&c->c_refcount);
 135         CDEBUG (D_INFO, "connection=%p refcount %d to %s\n",
 136                 c, atomic_read(&c->c_refcount),
 137                 libcfs_nid2str(c->c_peer.nid));
 138         RETURN(c);
 139 }
 140
 141 void ptlrpc_init_connection(void)
 142 {
 143         INIT_LIST_HEAD(&conn_list);
 144         INIT_LIST_HEAD(&conn_unused_list);
 145         conn_lock = SPIN_LOCK_UNLOCKED;
 146 }
 147
 148 void ptlrpc_cleanup_connection(void)
 149 {
 150         struct list_head *tmp, *pos;
 151         struct ptlrpc_connection *c;
 152
 153         spin_lock(&conn_lock);
 154         list_for_each_safe(tmp, pos, &conn_unused_list) {
 155                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
 156                 list_del(&c->c_link);
 157                 OBD_FREE(c, sizeof(*c));
 158         }
 159         list_for_each_safe(tmp, pos, &conn_list) {
 160                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
 161                 CERROR("Connection %p/%s has refcount %d (nid=%s)\n",
 162                        c, c->c_remote_uuid.uuid, atomic_read(&c->c_refcount),
 163                        libcfs_nid2str(c->c_peer.nid));
 164                 list_del(&c->c_link);
 165                 OBD_FREE(c, sizeof(*c));
 166         }
 167         spin_unlock(&conn_lock);
 168 }