xref: /dragonfly/contrib/lvm2/dist/lib/zero/zero.c (revision 0ca59c34)
1 /*	$NetBSD: zero.c,v 1.1.1.2 2009/12/02 00:26:25 haad Exp $	*/
2 
3 /*
4  * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
5  *
6  * This file is part of LVM2.
7  *
8  * This copyrighted material is made available to anyone wishing to use,
9  * modify, copy, or redistribute it subject to the terms and conditions
10  * of the GNU Lesser General Public License v.2.1.
11  *
12  * You should have received a copy of the GNU Lesser General Public License
13  * along with this program; if not, write to the Free Software Foundation,
14  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
15  */
16 
17 #include "lib.h"
18 #include "toolcontext.h"
19 #include "segtype.h"
20 #include "display.h"
21 #include "text_export.h"
22 #include "text_import.h"
23 #include "config.h"
24 #include "str_list.h"
25 #include "targets.h"
26 #include "lvm-string.h"
27 #include "activate.h"
28 #include "metadata.h"
29 
30 static const char *_zero_name(const struct lv_segment *seg)
31 {
32 	return seg->segtype->name;
33 }
34 
35 static int _zero_merge_segments(struct lv_segment *seg1, struct lv_segment *seg2)
36 {
37 	seg1->len += seg2->len;
38 	seg1->area_len += seg2->area_len;
39 
40 	return 1;
41 }
42 
43 #ifdef DEVMAPPER_SUPPORT
44 static int _zero_add_target_line(struct dev_manager *dm __attribute((unused)),
45 				 struct dm_pool *mem __attribute((unused)),
46 				 struct cmd_context *cmd __attribute((unused)),
47 				 void **target_state __attribute((unused)),
48 				 struct lv_segment *seg __attribute((unused)),
49 				 struct dm_tree_node *node,uint64_t len,
50 				 uint32_t *pvmove_mirror_count __attribute((unused)))
51 {
52 	return dm_tree_node_add_zero_target(node, len);
53 }
54 
55 static int _zero_target_present(struct cmd_context *cmd,
56 				const struct lv_segment *seg __attribute((unused)),
57 				unsigned *attributes __attribute((unused)))
58 {
59 	static int _zero_checked = 0;
60 	static int _zero_present = 0;
61 
62 	if (!_zero_checked)
63 		_zero_present = target_present(cmd, "zero", 1);
64 
65 	_zero_checked = 1;
66 
67 	return _zero_present;
68 }
69 #endif
70 
71 static int _zero_modules_needed(struct dm_pool *mem,
72 				const struct lv_segment *seg __attribute((unused)),
73 				struct dm_list *modules)
74 {
75 	if (!str_list_add(mem, modules, "zero")) {
76 		log_error("zero module string list allocation failed");
77 		return 0;
78 	}
79 
80 	return 1;
81 }
82 
83 static void _zero_destroy(const struct segment_type *segtype)
84 {
85 	dm_free((void *) segtype);
86 }
87 
88 static struct segtype_handler _zero_ops = {
89 	.name = _zero_name,
90 	.merge_segments = _zero_merge_segments,
91 #ifdef DEVMAPPER_SUPPORT
92 	.add_target_line = _zero_add_target_line,
93 	.target_present = _zero_target_present,
94 #endif
95 	.modules_needed = _zero_modules_needed,
96 	.destroy = _zero_destroy,
97 };
98 
99 struct segment_type *init_zero_segtype(struct cmd_context *cmd)
100 {
101 	struct segment_type *segtype = dm_malloc(sizeof(*segtype));
102 
103 	if (!segtype)
104 		return_NULL;
105 
106 	segtype->cmd = cmd;
107 	segtype->ops = &_zero_ops;
108 	segtype->name = "zero";
109 	segtype->private = NULL;
110 	segtype->flags = SEG_CAN_SPLIT | SEG_VIRTUAL | SEG_CANNOT_BE_ZEROED;
111 
112 	log_very_verbose("Initialised segtype: %s", segtype->name);
113 
114 	return segtype;
115 }
116