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
30static const char *_zero_name(const struct lv_segment *seg)
31{
32	return seg->segtype->name;
33}
34
35static 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
44static 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
55static 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
71static 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
83static void _zero_destroy(const struct segment_type *segtype)
84{
85	dm_free((void *) segtype);
86}
87
88static 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
99struct 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