1 /* $NetBSD: dm_target_linear.c,v 1.37 2020/01/21 16:27:53 tkusumi 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 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: dm_target_linear.c,v 1.37 2020/01/21 16:27:53 tkusumi Exp $");
33
34 /*
35 * This file implements initial version of device-mapper linear target.
36 */
37
38 #include <sys/types.h>
39 #include <sys/param.h>
40 #include <sys/buf.h>
41 #include <sys/kmem.h>
42 #include <sys/lwp.h>
43
44 #include <machine/int_fmtio.h>
45
46 #include "dm.h"
47
48 /*
49 * Allocate target specific config data, and link them to table.
50 * This function is called only when, flags is not READONLY and
51 * therefore we can add things to pdev list. This should not a
52 * problem because this routine is called only from dm_table_load_ioctl.
53 * @argv[0] is name,
54 * @argv[1] is physical data offset.
55 */
56 int
dm_target_linear_init(dm_table_entry_t * table_en,int argc,char ** argv)57 dm_target_linear_init(dm_table_entry_t *table_en, int argc, char **argv)
58 {
59 dm_target_linear_config_t *tlc;
60 dm_pdev_t *dmp;
61
62 if (argc != 2) {
63 printf("Linear target takes 2 args, %d given\n", argc);
64 return EINVAL;
65 }
66
67 aprint_debug("Linear target init function called %s--%s!!\n",
68 argv[0], argv[1]);
69
70 /* Insert dmp to global pdev list */
71 if ((dmp = dm_pdev_insert(argv[0])) == NULL)
72 return ENOENT;
73
74 tlc = kmem_alloc(sizeof(dm_target_linear_config_t), KM_SLEEP);
75 tlc->pdev = dmp;
76 tlc->offset = atoi64(argv[1]);
77
78 dm_table_add_deps(table_en, dmp);
79 table_en->target_config = tlc;
80
81 return 0;
82 }
83
84 /*
85 * Table routine is called to get params string, which is target
86 * specific. When dm_table_status_ioctl is called with flag
87 * DM_STATUS_TABLE_FLAG I have to sent params string back.
88 */
89 char *
dm_target_linear_table(void * target_config)90 dm_target_linear_table(void *target_config)
91 {
92 dm_target_linear_config_t *tlc;
93 char *params;
94 tlc = target_config;
95
96 aprint_debug("Linear target table function called\n");
97
98 params = kmem_alloc(DM_MAX_PARAMS_SIZE, KM_SLEEP);
99 snprintf(params, DM_MAX_PARAMS_SIZE, "%s %" PRIu64,
100 tlc->pdev->udev_name, tlc->offset);
101
102 return params;
103 }
104
105 /*
106 * Do IO operation, called from dmstrategy routine.
107 */
108 int
dm_target_linear_strategy(dm_table_entry_t * table_en,struct buf * bp)109 dm_target_linear_strategy(dm_table_entry_t *table_en, struct buf *bp)
110 {
111 dm_target_linear_config_t *tlc;
112
113 tlc = table_en->target_config;
114
115 bp->b_blkno += tlc->offset;
116
117 VOP_STRATEGY(tlc->pdev->pdev_vnode, bp);
118
119 return 0;
120 }
121
122 /*
123 * Sync underlying disk caches.
124 */
125 int
dm_target_linear_sync(dm_table_entry_t * table_en)126 dm_target_linear_sync(dm_table_entry_t *table_en)
127 {
128 int cmd;
129 dm_target_linear_config_t *tlc;
130
131 tlc = table_en->target_config;
132
133 cmd = 1;
134
135 return VOP_IOCTL(tlc->pdev->pdev_vnode, DIOCCACHESYNC, &cmd,
136 FREAD|FWRITE, kauth_cred_get());
137 }
138
139 /*
140 * Destroy target specific data. Decrement table pdevs.
141 */
142 int
dm_target_linear_destroy(dm_table_entry_t * table_en)143 dm_target_linear_destroy(dm_table_entry_t *table_en)
144 {
145
146 /*
147 * Destroy function is called for every target even if it
148 * doesn't have target_config.
149 */
150 if (table_en->target_config == NULL)
151 goto out;
152
153 dm_target_linear_config_t *tlc = table_en->target_config;
154
155 /* Decrement pdev ref counter if 0 remove it */
156 dm_pdev_decr(tlc->pdev);
157
158 kmem_free(tlc, sizeof(*tlc));
159
160 out:
161 /* Unbusy target so we can unload it */
162 dm_target_unbusy(table_en->target);
163 return 0;
164 }
165
166 #if 0
167 /*
168 * Register upcall device.
169 * Linear target doesn't need any upcall devices but other targets like
170 * mirror, snapshot, multipath, stripe will use this functionality.
171 */
172 int
173 dm_target_linear_upcall(dm_table_entry_t *table_en, struct buf *bp)
174 {
175
176 return 0;
177 }
178 #endif
179
180 /*
181 * Query physical block size of this target
182 * For a linear target this is just the sector size of the underlying device
183 */
184 int
dm_target_linear_secsize(dm_table_entry_t * table_en,unsigned int * secsizep)185 dm_target_linear_secsize(dm_table_entry_t *table_en, unsigned int *secsizep)
186 {
187 dm_target_linear_config_t *tlc;
188 unsigned int secsize;
189
190 secsize = 0;
191
192 tlc = table_en->target_config;
193 if (tlc != NULL)
194 secsize = tlc->pdev->pdev_secsize;
195
196 *secsizep = secsize;
197
198 return 0;
199 }
200