1 /*$NetBSD: dm_target_mirror.c,v 1.8 2010/01/04 00:12:22 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 <dev/disk/dm/dm.h>
36 
37 typedef struct target_mirror_config {
38 #define MAX_MIRROR_COPIES 4
39 	dm_pdev_t *orig;
40 	dm_pdev_t *copies[MAX_MIRROR_COPIES];
41 
42 	/* copied blocks bitmaps administration etc*/
43 	dm_pdev_t *log_pdev;	/* for administration */
44 	uint64_t log_regionsize;	/* blocksize of mirror */
45 
46 	/* list of parts that still need copied etc.; run length encoded? */
47 } dm_target_mirror_config_t;
48 
49 int dm_target_mirror_init(dm_table_entry_t *, int, char **);
50 char *dm_target_mirror_table(void *);
51 int dm_target_mirror_strategy(dm_table_entry_t *, struct buf *);
52 int dm_target_mirror_deps(dm_table_entry_t *, prop_array_t);
53 int dm_target_mirror_destroy(dm_table_entry_t *);
54 
55 /*
56  * Init function called from dm_table_load_ioctl.
57  * start length mirror log_type #logargs logarg1 ... logargN #devs device1 offset1 ... deviceN offsetN
58  * 0 52428800 mirror clustered_disk 4 253:2 1024 UUID block_on_error 3 253:3 0 253:4 0 253:5 0
59  */
60 int
61 dm_target_mirror_init(dm_table_entry_t *table_en, int argc, char **argv)
62 {
63 
64 	kprintf("Mirror target init function called!!\n");
65 
66 	return ENOSYS;
67 }
68 
69 /* Table routine called to get params string. */
70 char *
71 dm_target_mirror_table(void *target_config)
72 {
73 	return NULL;
74 }
75 
76 /* Strategy routine called from dm_strategy. */
77 int
78 dm_target_mirror_strategy(dm_table_entry_t *table_en, struct buf *bp)
79 {
80 
81 	kprintf("Mirror target read function called!!\n");
82 
83 	bp->b_error = EIO;
84 	bp->b_resid = 0;
85 
86 	biodone(bp);
87 
88 	return 0;
89 }
90 
91 /* Doesn't do anything here. */
92 int
93 dm_target_mirror_destroy(dm_table_entry_t *table_en)
94 {
95 	/* Unbusy target so we can unload it */
96 	dm_target_unbusy(table_en->target);
97 
98 	return 0;
99 }
100 
101 /* Doesn't not need to do anything here. */
102 int
103 dm_target_mirror_deps(dm_table_entry_t *table_en, prop_array_t prop_array)
104 {
105 	return 0;
106 }
107