Home | History | Annotate | Line # | Download | only in locking 
      1 /*	$NetBSD: no_locking.c,v 1.1.1.2 2009/12/02 00:26:24 haad Exp $	*/
      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 }
    105