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         char str[PTL_NALFMT_SIZE];
  41         struct list_head *tmp;
  42         struct ptlrpc_connection *c;
  43         ENTRY;
  44
  45         list_for_each(tmp, &conn_list) {
  46                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  47                 CERROR("Connection %p/%s has refcount %d (nid=%s on %s)\n",
  48                        c, c->c_remote_uuid.uuid, atomic_read(&c->c_refcount),
  49                        ptlrpc_peernid2str(&c->c_peer, str),
  50                        c->c_peer.peer_ni->pni_name);
  51         }
  52         EXIT;
  53 }
  54
  55 struct ptlrpc_connection *ptlrpc_get_connection(struct ptlrpc_peer *peer,
  56                                                 struct obd_uuid *uuid)
  57 {
  58         char str[PTL_NALFMT_SIZE];
  59         struct list_head *tmp, *pos;
  60         struct ptlrpc_connection *c;
  61         ENTRY;
  62
  63
  64         CDEBUG(D_INFO, "peer is %s on %s\n",
  65                ptlrpc_peernid2str(peer, str), peer->peer_ni->pni_name);
  66
  67         spin_lock(&conn_lock);
  68         list_for_each(tmp, &conn_list) {
  69                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  70                 if (peer->peer_nid == c->c_peer.peer_nid &&
  71                     peer->peer_ni == c->c_peer.peer_ni) {
  72                         ptlrpc_connection_addref(c);
  73                         GOTO(out, c);
  74                 }
  75         }
  76
  77         list_for_each_safe(tmp, pos, &conn_unused_list) {
  78                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
  79                 if (peer->peer_nid == c->c_peer.peer_nid &&
  80                     peer->peer_ni == c->c_peer.peer_ni) {
  81                         ptlrpc_connection_addref(c);
  82                         list_del(&c->c_link);
  83                         list_add(&c->c_link, &conn_list);
  84                         GOTO(out, c);
  85                 }
  86         }
  87
  88         /* FIXME: this should be a slab once we can validate slab addresses
  89          * without OOPSing */
  90         OBD_ALLOC_GFP(c, sizeof(*c), GFP_ATOMIC);
  91
  92         if (c == NULL)
  93                 GOTO(out, c);
  94
  95         if (uuid && uuid->uuid)                         /* XXX ???? */
  96                 obd_str2uuid(&c->c_remote_uuid, uuid->uuid);
  97         atomic_set(&c->c_refcount, 0);
  98         memcpy(&c->c_peer, peer, sizeof(c->c_peer));
  99
 100         ptlrpc_connection_addref(c);
 101
 102         list_add(&c->c_link, &conn_list);
 103
 104         EXIT;
 105  out:
 106         spin_unlock(&conn_lock);
 107         return c;
 108 }
 109
 110 int ptlrpc_put_connection(struct ptlrpc_connection *c)
 111 {
 112         char str[PTL_NALFMT_SIZE];
 113         int rc = 0;
 114         ENTRY;
 115
 116         if (c == NULL) {
 117                 CERROR("NULL connection\n");
 118                 RETURN(0);
 119         }
 120
 121         CDEBUG (D_INFO, "connection=%p refcount %d to %s on %s\n",
 122                 c, atomic_read(&c->c_refcount) - 1,
 123                 ptlrpc_peernid2str(&c->c_peer, str),
 124                 c->c_peer.peer_ni->pni_name);
 125
 126         if (atomic_dec_and_test(&c->c_refcount)) {
 127                 spin_lock(&conn_lock);
 128                 list_del(&c->c_link);
 129                 list_add(&c->c_link, &conn_unused_list);
 130                 spin_unlock(&conn_lock);
 131                 rc = 1;
 132         }
 133         if (atomic_read(&c->c_refcount) < 0)
 134                 CERROR("connection %p refcount %d!\n",
 135                        c, atomic_read(&c->c_refcount));
 136
 137         RETURN(rc);
 138 }
 139
 140 struct ptlrpc_connection *ptlrpc_connection_addref(struct ptlrpc_connection *c)
 141 {
 142         char str[PTL_NALFMT_SIZE];
 143         ENTRY;
 144         atomic_inc(&c->c_refcount);
 145         CDEBUG (D_INFO, "connection=%p refcount %d to %s on %s\n",
 146                 c, atomic_read(&c->c_refcount),
 147                 ptlrpc_peernid2str(&c->c_peer, str),
 148                 c->c_peer.peer_ni->pni_name);
 149         RETURN(c);
 150 }
 151
 152 void ptlrpc_init_connection(void)
 153 {
 154         INIT_LIST_HEAD(&conn_list);
 155         INIT_LIST_HEAD(&conn_unused_list);
 156         conn_lock = SPIN_LOCK_UNLOCKED;
 157 }
 158
 159 void ptlrpc_cleanup_connection(void)
 160 {
 161         char str[PTL_NALFMT_SIZE];
 162         struct list_head *tmp, *pos;
 163         struct ptlrpc_connection *c;
 164
 165         spin_lock(&conn_lock);
 166         list_for_each_safe(tmp, pos, &conn_unused_list) {
 167                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
 168                 list_del(&c->c_link);
 169                 OBD_FREE(c, sizeof(*c));
 170         }
 171         list_for_each_safe(tmp, pos, &conn_list) {
 172                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
 173                 CERROR("Connection %p/%s has refcount %d (nid=%s on %s)\n",
 174                        c, c->c_remote_uuid.uuid, atomic_read(&c->c_refcount),
 175                        ptlrpc_peernid2str(&c->c_peer, str),
 176                        c->c_peer.peer_ni->pni_name);
 177                 list_del(&c->c_link);
 178                 OBD_FREE(c, sizeof(*c));
 179         }
 180         spin_unlock(&conn_lock);
 181 }