xref: /dflybsd-src/sys/dev/disk/dm/dm_target_error.c (revision 3484c4aa8f394b9ac6147d925d119ffb4cd9edb6)
1 /*        $NetBSD: dm_target_error.c,v 1.10 2010/01/04 00:12:22 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 
37 #include <sys/buf.h>
38 
39 #include <dev/disk/dm/dm.h>
40 
41 /* Init function called from dm_table_load_ioctl. */
42 static int
43 dm_target_error_init(dm_dev_t *dmv, void **target_config, char *argv)
44 {
45 
46 	kprintf("Error target init function called!!\n");
47 
48 	*target_config = NULL;
49 
50 	dmv->dev_type = DM_ERROR_DEV;
51 
52 	return 0;
53 }
54 
55 /* Table routine called to get params string. */
56 static char *
57 dm_target_error_table(void *target_config)
58 {
59 	return NULL;
60 }
61 
62 /* Strategy routine called from dm_strategy. */
63 static int
64 dm_target_error_strategy(dm_table_entry_t *table_en, struct buf *bp)
65 {
66 
67 	/* kprintf("Error target read function called!!\n"); */
68 
69 	bp->b_error = EIO;
70 	bp->b_resid = 0;
71 
72 	biodone(&bp->b_bio1);
73 
74 	return 0;
75 }
76 
77 /* Doesn't do anything here. */
78 static int
79 dm_target_error_destroy(dm_table_entry_t *table_en)
80 {
81 	table_en->target_config = NULL;
82 
83 	return 0;
84 }
85 
86 /* Doesn't not need to do anything here. */
87 static int
88 dm_target_error_deps(dm_table_entry_t *table_en, prop_array_t prop_array)
89 {
90 	return 0;
91 }
92 
93 /* Unsupported for this target. */
94 static int
95 dm_target_error_upcall(dm_table_entry_t *table_en, struct buf *bp)
96 {
97 	return 0;
98 }
99 
100 static int
101 dmte_mod_handler(module_t mod, int type, void *unused)
102 {
103 	dm_target_t *dmt = NULL;
104 	int err = 0;
105 
106 	switch(type) {
107 	case MOD_LOAD:
108 		if ((dmt = dm_target_lookup("error")) != NULL) {
109 			dm_target_unbusy(dmt);
110 			return EEXIST;
111 		}
112 		dmt = dm_target_alloc("error");
113 		dmt->version[0] = 1;
114 		dmt->version[1] = 0;
115 		dmt->version[2] = 0;
116 		strlcpy(dmt->name, "error", DM_MAX_TYPE_NAME);
117 		dmt->init = &dm_target_error_init;
118 		dmt->table = &dm_target_error_table;
119 		dmt->strategy = &dm_target_error_strategy;
120 		dmt->deps = &dm_target_error_deps;
121 		dmt->destroy = &dm_target_error_destroy;
122 		dmt->upcall = &dm_target_error_upcall;
123 		dmt->dump = NULL;
124 
125 		err = dm_target_insert(dmt);
126 		if (err == 0)
127 			kprintf("dm_target_error: Successfully initialized\n");
128 		break;
129 
130 	case MOD_UNLOAD:
131 		err = dm_target_rem("error");
132 		if (err == 0)
133 			kprintf("dm_target_error: unloaded\n");
134 		break;
135 
136 	default:
137 		break;
138 	}
139 
140 	return err;
141 }
142 
143 DM_TARGET_BUILTIN(dm_target_error, dmte_mod_handler);
144