drivers/staging/lustre/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.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2011, 2012, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  */
  32
  33 #define DEBUG_SUBSYSTEM S_RPC
  34
  35 #include <obd.h>
  36 #include <obd_support.h>
  37 #include <obd_class.h>
  38 #include <lustre_lib.h>
  39 #include <lustre_ha.h>
  40 #include <lustre_net.h>
  41 #include <lprocfs_status.h>
  42
  43 #define NIDS_MAX        32
  44
  45 struct uuid_nid_data {
  46         struct list_head       un_list;
  47         struct obd_uuid  un_uuid;
  48         int           un_nid_count;
  49         lnet_nid_t       un_nids[NIDS_MAX];
  50 };
  51
  52 /* FIXME: This should probably become more elegant than a global linked list */
  53 static struct list_head g_uuid_list;
  54 static spinlock_t       g_uuid_lock;
  55
  56 void class_init_uuidlist(void)
  57 {
  58         INIT_LIST_HEAD(&g_uuid_list);
  59         spin_lock_init(&g_uuid_lock);
  60 }
  61
  62 void class_exit_uuidlist(void)
  63 {
  64         /* delete all */
  65         class_del_uuid(NULL);
  66 }
  67
  68 int lustre_uuid_to_peer(const char *uuid, lnet_nid_t *peer_nid, int index)
  69 {
  70         struct uuid_nid_data *data;
  71         struct obd_uuid tmp;
  72         int rc = -ENOENT;
  73
  74         obd_str2uuid(&tmp, uuid);
  75         spin_lock(&g_uuid_lock);
  76         list_for_each_entry(data, &g_uuid_list, un_list) {
  77                 if (obd_uuid_equals(&data->un_uuid, &tmp)) {
  78                         if (index >= data->un_nid_count)
  79                                 break;
  80
  81                         rc = 0;
  82                         *peer_nid = data->un_nids[index];
  83                         break;
  84                 }
  85         }
  86         spin_unlock(&g_uuid_lock);
  87         return rc;
  88 }
  89 EXPORT_SYMBOL(lustre_uuid_to_peer);
  90
  91 /* Add a nid to a niduuid.  Multiple nids can be added to a single uuid;
  92  * LNET will choose the best one.
  93  */
  94 int class_add_uuid(const char *uuid, __u64 nid)
  95 {
  96         struct uuid_nid_data *data, *entry;
  97         int found = 0;
  98
  99         LASSERT(nid != 0);  /* valid newconfig NID is never zero */
 100
 101         if (strlen(uuid) > UUID_MAX - 1)
 102                 return -EOVERFLOW;
 103
 104         data = kzalloc(sizeof(*data), GFP_NOFS);
 105         if (!data)
 106                 return -ENOMEM;
 107
 108         obd_str2uuid(&data->un_uuid, uuid);
 109         data->un_nids[0] = nid;
 110         data->un_nid_count = 1;
 111
 112         spin_lock(&g_uuid_lock);
 113         list_for_each_entry(entry, &g_uuid_list, un_list) {
 114                 if (obd_uuid_equals(&entry->un_uuid, &data->un_uuid)) {
 115                         int i;
 116
 117                         found = 1;
 118                         for (i = 0; i < entry->un_nid_count; i++)
 119                                 if (nid == entry->un_nids[i])
 120                                         break;
 121
 122                         if (i == entry->un_nid_count) {
 123                                 LASSERT(entry->un_nid_count < NIDS_MAX);
 124                                 entry->un_nids[entry->un_nid_count++] = nid;
 125                         }
 126                         break;
 127                 }
 128         }
 129         if (!found)
 130                 list_add(&data->un_list, &g_uuid_list);
 131         spin_unlock(&g_uuid_lock);
 132
 133         if (found) {
 134                 CDEBUG(D_INFO, "found uuid %s %s cnt=%d\n", uuid,
 135                        libcfs_nid2str(nid), entry->un_nid_count);
 136                 kfree(data);
 137         } else {
 138                 CDEBUG(D_INFO, "add uuid %s %s\n", uuid, libcfs_nid2str(nid));
 139         }
 140         return 0;
 141 }
 142
 143 /* Delete the nids for one uuid if specified, otherwise delete all */
 144 int class_del_uuid(const char *uuid)
 145 {
 146         LIST_HEAD(deathrow);
 147         struct uuid_nid_data *data;
 148         struct uuid_nid_data *temp;
 149
 150         spin_lock(&g_uuid_lock);
 151         if (uuid) {
 152                 struct obd_uuid tmp;
 153
 154                 obd_str2uuid(&tmp, uuid);
 155                 list_for_each_entry(data, &g_uuid_list, un_list) {
 156                         if (obd_uuid_equals(&data->un_uuid, &tmp)) {
 157                                 list_move(&data->un_list, &deathrow);
 158                                 break;
 159                         }
 160                 }
 161         } else {
 162                 list_splice_init(&g_uuid_list, &deathrow);
 163         }
 164         spin_unlock(&g_uuid_lock);
 165
 166         if (uuid && list_empty(&deathrow)) {
 167                 CDEBUG(D_INFO, "Try to delete a non-existent uuid %s\n", uuid);
 168                 return -EINVAL;
 169         }
 170
 171         list_for_each_entry_safe(data, temp, &deathrow, un_list) {
 172                 list_del(&data->un_list);
 173
 174                 CDEBUG(D_INFO, "del uuid %s %s/%d\n",
 175                        obd_uuid2str(&data->un_uuid),
 176                        libcfs_nid2str(data->un_nids[0]),
 177                        data->un_nid_count);
 178
 179                 kfree(data);
 180         }
 181
 182         return 0;
 183 }
 184
 185 /* check if @nid exists in nid list of @uuid */
 186 int class_check_uuid(struct obd_uuid *uuid, __u64 nid)
 187 {
 188         struct uuid_nid_data *entry;
 189         int found = 0;
 190
 191         CDEBUG(D_INFO, "check if uuid %s has %s.\n",
 192                obd_uuid2str(uuid), libcfs_nid2str(nid));
 193
 194         spin_lock(&g_uuid_lock);
 195         list_for_each_entry(entry, &g_uuid_list, un_list) {
 196                 int i;
 197
 198                 if (!obd_uuid_equals(&entry->un_uuid, uuid))
 199                         continue;
 200
 201                 /* found the uuid, check if it has @nid */
 202                 for (i = 0; i < entry->un_nid_count; i++) {
 203                         if (entry->un_nids[i] == nid) {
 204                                 found = 1;
 205                                 break;
 206                         }
 207                 }
 208                 break;
 209         }
 210         spin_unlock(&g_uuid_lock);
 211         return found;
 212 }
 213 EXPORT_SYMBOL(class_check_uuid);