lustre/obdclass/lustre_peer.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (c) 2002, 2003 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of the Lustre file system, http://www.lustre.org
   7  *   Lustre is a trademark of Cluster File Systems, Inc.
   8  *
   9  *   You may have signed or agreed to another license before downloading
  10  *   this software.  If so, you are bound by the terms and conditions
  11  *   of that agreement, and the following does not apply to you.  See the
  12  *   LICENSE file included with this distribution for more information.
  13  *
  14  *   If you did not agree to a different license, then this copy of Lustre
  15  *   is open source software; you can redistribute it and/or modify it
  16  *   under the terms of version 2 of the GNU General Public License as
  17  *   published by the Free Software Foundation.
  18  *
  19  *   In either case, Lustre is distributed in the hope that it will be
  20  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  21  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  *   license text for more details.
  23  *
  24  */
  25
  26 #define DEBUG_SUBSYSTEM S_RPC
  27
  28 #ifndef __KERNEL__
  29 # include <liblustre.h>
  30 #endif
  31 #include <obd.h>
  32 #include <obd_support.h>
  33 #include <obd_class.h>
  34 #include <lustre_lib.h>
  35 #include <lustre_ha.h>
  36 #include <lustre_net.h>
  37 #include <lprocfs_status.h>
  38
  39 struct uuid_nid_data {
  40         struct list_head un_list;
  41         lnet_nid_t       un_nid;
  42         char            *un_uuid;
  43         int              un_count;  /* nid/uuid pair refcount */
  44 };
  45
  46 /* FIXME: This should probably become more elegant than a global linked list */
  47 static struct list_head g_uuid_list;
  48 static spinlock_t       g_uuid_lock;
  49
  50 void class_init_uuidlist(void)
  51 {
  52         CFS_INIT_LIST_HEAD(&g_uuid_list);
  53         spin_lock_init(&g_uuid_lock);
  54 }
  55
  56 void class_exit_uuidlist(void)
  57 {
  58         /* delete all */
  59         class_del_uuid(NULL);
  60 }
  61
  62 int lustre_uuid_to_peer(const char *uuid, lnet_nid_t *peer_nid, int index)
  63 {
  64         struct list_head *tmp;
  65
  66         spin_lock (&g_uuid_lock);
  67
  68         list_for_each(tmp, &g_uuid_list) {
  69                 struct uuid_nid_data *data =
  70                         list_entry(tmp, struct uuid_nid_data, un_list);
  71
  72                 if (!strcmp(data->un_uuid, uuid) &&
  73                     index-- == 0) {
  74                         *peer_nid = data->un_nid;
  75
  76                         spin_unlock (&g_uuid_lock);
  77                         return 0;
  78                 }
  79         }
  80
  81         spin_unlock (&g_uuid_lock);
  82         return -ENOENT;
  83 }
  84
  85 /* Add a nid to a niduuid.  Multiple nids can be added to a single uuid;
  86    LNET will choose the best one. */
  87 int class_add_uuid(const char *uuid, __u64 nid)
  88 {
  89         struct uuid_nid_data *data, *entry;
  90         int nob = strnlen (uuid, CFS_PAGE_SIZE) + 1;
  91         int found = 0;
  92
  93         LASSERT(nid != 0);  /* valid newconfig NID is never zero */
  94
  95         if (nob > CFS_PAGE_SIZE)
  96                 return -EINVAL;
  97
  98         OBD_ALLOC(data, sizeof(*data));
  99         if (data == NULL)
 100                 return -ENOMEM;
 101
 102         OBD_ALLOC(data->un_uuid, nob);
 103         if (data == NULL) {
 104                 OBD_FREE(data, sizeof(*data));
 105                 return -ENOMEM;
 106         }
 107
 108         memcpy(data->un_uuid, uuid, nob);
 109         data->un_nid = nid;
 110         data->un_count = 1;
 111
 112         spin_lock (&g_uuid_lock);
 113
 114         list_for_each_entry(entry, &g_uuid_list, un_list) {
 115                 if (entry->un_nid == nid &&
 116                     (strcmp(entry->un_uuid, uuid) == 0)) {
 117                         found++;
 118                         entry->un_count++;
 119                         break;
 120                 }
 121         }
 122         if (!found)
 123                 list_add(&data->un_list, &g_uuid_list);
 124         spin_unlock (&g_uuid_lock);
 125
 126         if (found) {
 127                 CDEBUG(D_INFO, "found uuid %s %s cnt=%d\n", uuid,
 128                        libcfs_nid2str(nid), entry->un_count);
 129                 OBD_FREE(data->un_uuid, nob);
 130                 OBD_FREE(data, sizeof(*data));
 131         } else {
 132                 CDEBUG(D_INFO, "add uuid %s %s\n", uuid, libcfs_nid2str(nid));
 133         }
 134         return 0;
 135 }
 136
 137 /* Delete the nids for one uuid if specified, otherwise delete all */
 138 int class_del_uuid(const char *uuid)
 139 {
 140         CFS_LIST_HEAD(deathrow);
 141         struct uuid_nid_data *data;
 142         int found = 0;
 143
 144         spin_lock (&g_uuid_lock);
 145         if (uuid == NULL) {
 146                 list_splice_init(&g_uuid_list, &deathrow);
 147                 found = 1;
 148         } else {
 149                 list_for_each_entry(data, &g_uuid_list, un_list) {
 150                         if (strcmp(data->un_uuid, uuid))
 151                                 continue;
 152                         --data->un_count;
 153                         LASSERT(data->un_count >= 0);
 154                         if (data->un_count == 0)
 155                                 list_move(&data->un_list, &deathrow);
 156                         found = 1;
 157                         break;
 158                 }
 159         }
 160         spin_unlock (&g_uuid_lock);
 161
 162         if (!found) {
 163                 if (uuid)
 164                         CERROR("Try to delete a non-existent uuid %s\n", uuid);
 165                 return -EINVAL;
 166         }
 167
 168         while (!list_empty(&deathrow)) {
 169                 data = list_entry(deathrow.next, struct uuid_nid_data, un_list);
 170                 list_del(&data->un_list);
 171
 172                 CDEBUG(D_INFO, "del uuid %s %s\n", data->un_uuid,
 173                        libcfs_nid2str(data->un_nid));
 174
 175                 OBD_FREE(data->un_uuid, strlen(data->un_uuid) + 1);
 176                 OBD_FREE(data, sizeof(*data));
 177         }
 178
 179         return 0;
 180 }