Whamcloud - gitweb
LU-2358 procfs: Implement /proc/fs/lustre/mgs/MGS/fstype as symlink
[fs/lustre-release.git] / lustre / obdclass / lustre_peer.c
1 /*
2  * GPL HEADER START
3  *
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 only,
8  * as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License version 2 for more details (a copy is included
14  * in the LICENSE file that accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License
17  * version 2 along with this program; If not, see
18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
19  *
20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21  * CA 95054 USA or visit www.sun.com if you need additional information or
22  * have any questions.
23  *
24  * GPL HEADER END
25  */
26 /*
27  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
28  * Use is subject to license terms.
29  *
30  * Copyright (c) 2011, Whamcloud, Inc.
31  */
32 /*
33  * This file is part of Lustre, http://www.lustre.org/
34  * Lustre is a trademark of Sun Microsystems, Inc.
35  */
36
37 #define DEBUG_SUBSYSTEM S_RPC
38
39 #ifndef __KERNEL__
40 # include <liblustre.h>
41 #endif
42 #include <obd.h>
43 #include <obd_support.h>
44 #include <obd_class.h>
45 #include <lustre_lib.h>
46 #include <lustre_ha.h>
47 #include <lustre_net.h>
48 #include <lprocfs_status.h>
49
50 #define NIDS_MAX        32
51
52 struct uuid_nid_data {
53         cfs_list_t       un_list;
54         struct obd_uuid  un_uuid;
55         int              un_nid_count;
56         lnet_nid_t       un_nids[NIDS_MAX];
57 };
58
59 /* FIXME: This should probably become more elegant than a global linked list */
60 static cfs_list_t       g_uuid_list;
61 static spinlock_t       g_uuid_lock;
62
63 void class_init_uuidlist(void)
64 {
65         CFS_INIT_LIST_HEAD(&g_uuid_list);
66         spin_lock_init(&g_uuid_lock);
67 }
68
69 void class_exit_uuidlist(void)
70 {
71         /* delete all */
72         class_del_uuid(NULL);
73 }
74
75 int lustre_uuid_to_peer(const char *uuid, lnet_nid_t *peer_nid, int index)
76 {
77         struct uuid_nid_data *data;
78         struct obd_uuid tmp;
79         int rc = -ENOENT;
80
81         obd_str2uuid(&tmp, uuid);
82         spin_lock(&g_uuid_lock);
83         cfs_list_for_each_entry(data, &g_uuid_list, un_list) {
84                 if (obd_uuid_equals(&data->un_uuid, &tmp)) {
85                         if (index >= data->un_nid_count)
86                                 break;
87
88                         rc = 0;
89                         *peer_nid = data->un_nids[index];
90                         break;
91                 }
92         }
93         spin_unlock(&g_uuid_lock);
94         return rc;
95 }
96 EXPORT_SYMBOL(lustre_uuid_to_peer);
97
98 /* Add a nid to a niduuid.  Multiple nids can be added to a single uuid;
99    LNET will choose the best one. */
100 int class_add_uuid(const char *uuid, __u64 nid)
101 {
102         struct uuid_nid_data *data, *entry;
103         int found = 0;
104
105         LASSERT(nid != 0);  /* valid newconfig NID is never zero */
106
107         if (strlen(uuid) > UUID_MAX - 1)
108                 return -EOVERFLOW;
109
110         OBD_ALLOC_PTR(data);
111         if (data == NULL)
112                 return -ENOMEM;
113
114         obd_str2uuid(&data->un_uuid, uuid);
115         data->un_nids[0] = nid;
116         data->un_nid_count = 1;
117
118         spin_lock(&g_uuid_lock);
119         cfs_list_for_each_entry(entry, &g_uuid_list, un_list) {
120                 if (obd_uuid_equals(&entry->un_uuid, &data->un_uuid)) {
121                         int i;
122
123                         found = 1;
124                         for (i = 0; i < entry->un_nid_count; i++)
125                                 if (nid == entry->un_nids[i])
126                                         break;
127
128                         if (i == entry->un_nid_count) {
129                                 LASSERT(entry->un_nid_count < NIDS_MAX);
130                                 entry->un_nids[entry->un_nid_count++] = nid;
131                         }
132                         break;
133                 }
134         }
135         if (!found)
136                 cfs_list_add(&data->un_list, &g_uuid_list);
137         spin_unlock(&g_uuid_lock);
138
139         if (found) {
140                 CDEBUG(D_INFO, "found uuid %s %s cnt=%d\n", uuid,
141                        libcfs_nid2str(nid), entry->un_nid_count);
142                 OBD_FREE(data, sizeof(*data));
143         } else {
144                 CDEBUG(D_INFO, "add uuid %s %s\n", uuid, libcfs_nid2str(nid));
145         }
146         return 0;
147 }
148 EXPORT_SYMBOL(class_add_uuid);
149
150 /* Delete the nids for one uuid if specified, otherwise delete all */
151 int class_del_uuid(const char *uuid)
152 {
153         CFS_LIST_HEAD(deathrow);
154         struct uuid_nid_data *data;
155
156         spin_lock(&g_uuid_lock);
157         if (uuid != NULL) {
158                 struct obd_uuid tmp;
159
160                 obd_str2uuid(&tmp, uuid);
161                 cfs_list_for_each_entry(data, &g_uuid_list, un_list) {
162                         if (obd_uuid_equals(&data->un_uuid, &tmp)) {
163                                 cfs_list_move(&data->un_list, &deathrow);
164                                 break;
165                         }
166                 }
167         } else
168                 cfs_list_splice_init(&g_uuid_list, &deathrow);
169         spin_unlock(&g_uuid_lock);
170
171         if (uuid != NULL && cfs_list_empty(&deathrow)) {
172                 CDEBUG(D_INFO, "Try to delete a non-existent uuid %s\n", uuid);
173                 return -EINVAL;
174         }
175
176         while (!cfs_list_empty(&deathrow)) {
177                 data = cfs_list_entry(deathrow.next, struct uuid_nid_data,
178                                       un_list);
179                 cfs_list_del(&data->un_list);
180
181                 CDEBUG(D_INFO, "del uuid %s %s/%d\n",
182                        obd_uuid2str(&data->un_uuid),
183                        libcfs_nid2str(data->un_nids[0]),
184                        data->un_nid_count);
185
186                 OBD_FREE(data, sizeof(*data));
187         }
188
189         return 0;
190 }
191
192 /* check if @nid exists in nid list of @uuid */
193 int class_check_uuid(struct obd_uuid *uuid, __u64 nid)
194 {
195         struct uuid_nid_data *entry;
196         int found = 0;
197         ENTRY;
198
199         CDEBUG(D_INFO, "check if uuid %s has %s.\n",
200                obd_uuid2str(uuid), libcfs_nid2str(nid));
201
202         spin_lock(&g_uuid_lock);
203         cfs_list_for_each_entry(entry, &g_uuid_list, un_list) {
204                 int i;
205
206                 if (!obd_uuid_equals(&entry->un_uuid, uuid))
207                         continue;
208
209                 /* found the uuid, check if it has @nid */
210                 for (i = 0; i < entry->un_nid_count; i++) {
211                         if (entry->un_nids[i] == nid) {
212                                 found = 1;
213                                 break;
214                         }
215                 }
216                 break;
217         }
218         spin_unlock(&g_uuid_lock);
219         RETURN(found);
220 }
221 EXPORT_SYMBOL(class_check_uuid);