dm_target_mirror.c revision 1.6 1 /*$NetBSD: dm_target_mirror.c,v 1.6 2009/06/05 19:56:40 haad Exp $*/
2
3 /*
4 * Copyright (c) 2009 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Adam Hamsik.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 /*
33 * This file implements initial version of device-mapper mirror target.
34 */
35 #include <sys/types.h>
36 #include <sys/param.h>
37
38 #include <sys/buf.h>
39
40 #include "dm.h"
41
42 #ifdef DM_TARGET_MODULE
43 /*
44 * Every target can be compiled directly to dm driver or as a
45 * separate module this part of target is used for loading targets
46 * to dm driver.
47 * Target can be unloaded from kernel only if there are no users of
48 * it e.g. there are no devices which uses that target.
49 */
50 #include <sys/kernel.h>
51 #include <sys/module.h>
52
53 MODULE(MODULE_CLASS_MISC, dm_target_mirror, "dm");
54
55 static int
56 dm_target_mirror_modcmd(modcmd_t cmd, void *arg)
57 {
58 dm_target_t *dmt;
59 int r;
60 dmt = NULL;
61
62 switch (cmd) {
63 case MODULE_CMD_INIT:
64 if ((dmt = dm_target_lookup("mirror")) != NULL){
65 dm_target_unbusy(dmt);
66 return EEXIST;
67 }
68 dmt = dm_target_alloc("mirror");
69
70 dmt->version[0] = 1;
71 dmt->version[1] = 0;
72 dmt->version[2] = 0;
73 strlcpy(dmt->name, "mirror", DM_MAX_TYPE_NAME);
74 dmt->init = &dm_target_mirror_init;
75 dmt->status = &dm_target_mirror_status;
76 dmt->strategy = &dm_target_mirror_strategy;
77 dmt->deps = &dm_target_mirror_deps;
78 dmt->destroy = &dm_target_mirror_destroy;
79 dmt->upcall = &dm_target_mirror_upcall;
80
81 r = dm_target_insert(dmt);
82
83 break;
84
85 case MODULE_CMD_FINI:
86 r = dm_target_rem("mirror");
87 break;
88
89 case MODULE_CMD_STAT:
90 return ENOTTY;
91
92 default:
93 return ENOTTY;
94 }
95
96 return r;
97 }
98
99 #endif
100
101 /*
102 * Init function called from dm_table_load_ioctl.
103 * start length mirror log_type #logargs logarg1 ... logargN #devs device1 offset1 ... deviceN offsetN
104 * 0 52428800 mirror clustered_disk 4 253:2 1024 UUID block_on_error 3 253:3 0 253:4 0 253:5 0
105 */
106 int
107 dm_target_mirror_init(dm_dev_t *dmv, void **target_config, prop_dictionary_t dict)
108 {
109
110 printf("Mirror target init function called!!\n");
111
112 *target_config = NULL;
113
114 dmv->dev_type = DM_MIRROR_DEV;
115
116 return ENOSYS;
117 }
118
119 /* Status routine called to get params string. */
120 char *
121 dm_target_mirror_status(void *target_config)
122 {
123 return NULL;
124 }
125
126 /* Strategy routine called from dm_strategy. */
127 int
128 dm_target_mirror_strategy(dm_table_entry_t *table_en, struct buf *bp)
129 {
130
131 printf("Mirror target read function called!!\n");
132
133 bp->b_error = EIO;
134 bp->b_resid = 0;
135
136 biodone(bp);
137
138 return 0;
139 }
140
141 /* Doesn't do anything here. */
142 int
143 dm_target_mirror_destroy(dm_table_entry_t *table_en)
144 {
145 table_en->target_config = NULL;
146
147 /* Unbusy target so we can unload it */
148 dm_target_unbusy(table_en->target);
149
150 return 0;
151 }
152
153 /* Doesn't not need to do anything here. */
154 int
155 dm_target_mirror_deps(dm_table_entry_t *table_en, prop_array_t prop_array)
156 {
157 return 0;
158 }
159
160 /* Unsupported for this target. */
161 int
162 dm_target_mirror_upcall(dm_table_entry_t *table_en, struct buf *bp)
163 {
164 return 0;
165 }
166