Whamcloud - gitweb
a34ff43ef7c0c4f7911b43d3cadaed9a3662dfe3
[fs/lustre-release.git] / 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 EXPORT_SYMTAB
24
25 #define DEBUG_SUBSYSTEM S_RPC
26
27 #include <linux/lustre_net.h>
28
29 static spinlock_t conn_lock;
30 static struct list_head conn_list;
31 static struct list_head conn_unused_list;
32
33 struct ptlrpc_connection *ptlrpc_get_connection(struct lustre_peer *peer)
34 {
35         struct list_head *tmp, *pos;
36         struct ptlrpc_connection *c;
37         ENTRY;
38
39         spin_lock(&conn_lock);
40         list_for_each(tmp, &conn_list) {
41                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
42                 if (memcmp(peer, &c->c_peer, sizeof(*peer)) == 0) {
43                         atomic_inc(&c->c_refcount);
44                         GOTO(out, c);
45                 }
46         }
47
48         list_for_each_safe(tmp, pos, &conn_unused_list) {
49                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
50                 if (memcmp(peer, &c->c_peer, sizeof(*peer)) == 0) {
51                         atomic_inc(&c->c_refcount);
52                         list_del(&c->c_link);
53                         list_add(&c->c_link, &conn_list);
54                         GOTO(out, c);
55                 }
56         }
57
58         /* FIXME: this should be a slab once we can validate slab addresses
59          * without OOPSing */
60         OBD_ALLOC(c, sizeof(*c));
61         if (c == NULL)
62                 GOTO(out, c);
63
64         c->c_level = LUSTRE_CONN_NEW;
65         c->c_xid_in = 1;
66         c->c_xid_out = 1;
67         c->c_generation = 1;
68         c->c_epoch = 1;
69         c->c_bootcount = 0;
70         atomic_set(&c->c_refcount, 1);
71         spin_lock_init(&c->c_lock);
72
73         memcpy(&c->c_peer, peer, sizeof(c->c_peer));
74         list_add(&c->c_link, &conn_list);
75
76         EXIT;
77  out:
78         spin_unlock(&conn_lock);
79         return c;
80 }
81
82 int ptlrpc_put_connection(struct ptlrpc_connection *c)
83 {
84         int rc = 0;
85         ENTRY;
86
87         if (atomic_dec_and_test(&c->c_refcount)) {
88                 spin_lock(&conn_lock);
89                 list_del(&c->c_link);
90                 list_add(&c->c_link, &conn_unused_list);
91                 spin_unlock(&conn_lock);
92                 rc = 1;
93         }
94
95         RETURN(rc);
96 }
97
98 struct ptlrpc_connection *ptlrpc_connection_addref(struct ptlrpc_connection *c)
99 {
100         ENTRY;
101         atomic_inc(&c->c_refcount);
102         RETURN(c);
103 }
104
105 void ptlrpc_init_connection(void)
106 {
107         INIT_LIST_HEAD(&conn_list);
108         INIT_LIST_HEAD(&conn_unused_list);
109         conn_lock = SPIN_LOCK_UNLOCKED;
110 }
111
112 void ptlrpc_cleanup_connection(void)
113 {
114         struct list_head *tmp, *pos;
115         struct ptlrpc_connection *c;
116
117         spin_lock(&conn_lock);
118         list_for_each_safe(tmp, pos, &conn_unused_list) {
119                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
120                 list_del(&c->c_link);
121                 OBD_FREE(c, sizeof(*c));
122         }
123         list_for_each_safe(tmp, pos, &conn_list) {
124                 c = list_entry(tmp, struct ptlrpc_connection, c_link);
125                 CERROR("Connection %p has refcount %d at cleanup (nid=%lu)!\n",
126                        c, atomic_read(&c->c_refcount),
127                        (unsigned long)c->c_peer.peer_nid);
128                 list_del(&c->c_link);
129                 OBD_FREE(c, sizeof(*c));
130         }
131         spin_unlock(&conn_lock);
132 }