external/gpl2/lvm2/dist/lib/locking/no_locking.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
   5  * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
   6  *
   7  * This file is part of LVM2.
   8  *
   9  * This copyrighted material is made available to anyone wishing to use,
  10  * modify, copy, or redistribute it subject to the terms and conditions
  11  * of the GNU Lesser General Public License v.2.1.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public License
  14  * along with this program; if not, write to the Free Software Foundation,
  15  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  16  */
  17
  18 #include "lib.h"
  19 #include "locking.h"
  20 #include "locking_types.h"
  21 #include "lvm-string.h"
  22 #include "activate.h"
  23
  24 #include <signal.h>
  25
  26 /*
  27  * No locking
  28  */
  29
  30 static void _no_fin_locking(void)
  31 {
  32         return;
  33 }
  34
  35 static void _no_reset_locking(void)
  36 {
  37         return;
  38 }
  39
  40 static int _no_lock_resource(struct cmd_context *cmd, const char *resource,
  41                              uint32_t flags)
  42 {
  43         switch (flags & LCK_SCOPE_MASK) {
  44         case LCK_VG:
  45                 break;
  46         case LCK_LV:
  47                 switch (flags & LCK_TYPE_MASK) {
  48                 case LCK_NULL:
  49                         return lv_deactivate(cmd, resource);
  50                 case LCK_UNLOCK:
  51                         return lv_resume_if_active(cmd, resource);
  52                 case LCK_READ:
  53                         return lv_activate_with_filter(cmd, resource, 0);
  54                 case LCK_WRITE:
  55                         return lv_suspend_if_active(cmd, resource);
  56                 case LCK_EXCL:
  57                         return lv_activate_with_filter(cmd, resource, 1);
  58                 default:
  59                         break;
  60                 }
  61                 break;
  62         default:
  63                 log_error("Unrecognised lock scope: %d",
  64                           flags & LCK_SCOPE_MASK);
  65                 return 0;
  66         }
  67
  68         return 1;
  69 }
  70
  71 static int _readonly_lock_resource(struct cmd_context *cmd,
  72                                    const char *resource,
  73                                    uint32_t flags)
  74 {
  75         if ((flags & LCK_TYPE_MASK) == LCK_WRITE &&
  76             (flags & LCK_SCOPE_MASK) == LCK_VG &&
  77             !(flags & LCK_CACHE) &&
  78             strcmp(resource, VG_GLOBAL)) {
  79                 log_error("Write locks are prohibited with --ignorelockingfailure.");
  80                 return 0;
  81         }
  82
  83         return _no_lock_resource(cmd, resource, flags);
  84 }
  85
  86 int init_no_locking(struct locking_type *locking, struct cmd_context *cmd __attribute((unused)))
  87 {
  88         locking->lock_resource = _no_lock_resource;
  89         locking->reset_locking = _no_reset_locking;
  90         locking->fin_locking = _no_fin_locking;
  91         locking->flags = LCK_CLUSTERED;
  92
  93         return 1;
  94 }
  95
  96 int init_readonly_locking(struct locking_type *locking, struct cmd_context *cmd __attribute((unused)))
  97 {
  98         locking->lock_resource = _readonly_lock_resource;
  99         locking->reset_locking = _no_reset_locking;
 100         locking->fin_locking = _no_fin_locking;
 101         locking->flags = 0;
 102
 103         return 1;
 104 }