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