xref: /netbsd-src/sys/dev/dm/dm_target_error.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*        $NetBSD: dm_target_error.c,v 1.11 2010/05/18 15:10:38 haad Exp $      */
2 
3 /*
4  * Copyright (c) 2008 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 error 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 /* dm_target_error.c */
43 int dm_target_error_init(dm_dev_t *, void**, char *);
44 char * dm_target_error_status(void *);
45 int dm_target_error_strategy(dm_table_entry_t *, struct buf *);
46 int dm_target_error_sync(dm_table_entry_t *);
47 int dm_target_error_deps(dm_table_entry_t *, prop_array_t);
48 int dm_target_error_destroy(dm_table_entry_t *);
49 int dm_target_error_upcall(dm_table_entry_t *, struct buf *);
50 
51 #ifdef DM_TARGET_MODULE
52 /*
53  * Every target can be compiled directly to dm driver or as a
54  * separate module this part of target is used for loading targets
55  * to dm driver.
56  * Target can be unloaded from kernel only if there are no users of
57  * it e.g. there are no devices which uses that target.
58  */
59 #include <sys/kernel.h>
60 #include <sys/module.h>
61 
62 MODULE(MODULE_CLASS_MISC, dm_target_error, "dm");
63 
64 static int
65 dm_target_error_modcmd(modcmd_t cmd, void *arg)
66 {
67 	dm_target_t *dmt;
68 	int r;
69 	dmt = NULL;
70 
71 	switch (cmd) {
72 	case MODULE_CMD_INIT:
73 		if ((dmt = dm_target_lookup("error")) != NULL) {
74 			dm_target_unbusy(dmt);
75 			return EEXIST;
76 		}
77 		dmt = dm_target_alloc("error");
78 
79 		dmt->version[0] = 1;
80 		dmt->version[1] = 0;
81 		dmt->version[2] = 0;
82 		strlcpy(dmt->name, "error", DM_MAX_TYPE_NAME);
83 		dmt->init = &dm_target_error_init;
84 		dmt->status = &dm_target_error_status;
85 		dmt->strategy = &dm_target_error_strategy;
86 		dmt->sync = &dm_target_error_sync;
87 		dmt->deps = &dm_target_error_deps;
88 		dmt->destroy = &dm_target_error_destroy;
89 		dmt->upcall = &dm_target_error_upcall;
90 
91 		r = dm_target_insert(dmt);
92 
93 		break;
94 
95 	case MODULE_CMD_FINI:
96 		r = dm_target_rem("error");
97 		break;
98 
99 	case MODULE_CMD_STAT:
100 		return ENOTTY;
101 
102 	default:
103 		return ENOTTY;
104 	}
105 
106 	return r;
107 }
108 #endif
109 
110 /* Init function called from dm_table_load_ioctl. */
111 int
112 dm_target_error_init(dm_dev_t * dmv, void **target_config, char *argv)
113 {
114 
115 	printf("Error target init function called!!\n");
116 
117 	*target_config = NULL;
118 
119 	dmv->dev_type = DM_ERROR_DEV;
120 
121 	return 0;
122 }
123 /* Status routine called to get params string. */
124 char *
125 dm_target_error_status(void *target_config)
126 {
127 	return NULL;
128 }
129 /* Strategy routine called from dm_strategy. */
130 int
131 dm_target_error_strategy(dm_table_entry_t * table_en, struct buf * bp)
132 {
133 
134 	printf("Error target read function called!!\n");
135 
136 	bp->b_error = EIO;
137 	bp->b_resid = 0;
138 
139 	biodone(bp);
140 
141 	return 0;
142 }
143 /* Sync underlying disk caches. */
144 int
145 dm_target_error_sync(dm_table_entry_t * table_en)
146 {
147 
148 	return 0;
149 }
150 /* Doesn't do anything here. */
151 int
152 dm_target_error_destroy(dm_table_entry_t * table_en)
153 {
154 	table_en->target_config = NULL;
155 
156 	/* Unbusy target so we can unload it */
157 	dm_target_unbusy(table_en->target);
158 
159 	return 0;
160 }
161 /* Doesn't not need to do anything here. */
162 int
163 dm_target_error_deps(dm_table_entry_t * table_en, prop_array_t prop_array)
164 {
165 	return 0;
166 }
167 /* Unsupported for this target. */
168 int
169 dm_target_error_upcall(dm_table_entry_t * table_en, struct buf * bp)
170 {
171 	return 0;
172 }
173