xref: /netbsd-src/sys/dev/dm/dm_target_linear.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*        $NetBSD: dm_target_linear.c,v 1.10 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 /*
34  * This file implements initial version of device-mapper dklinear target.
35  */
36 
37 #include <sys/types.h>
38 #include <sys/param.h>
39 
40 #include <sys/buf.h>
41 #include <sys/kmem.h>
42 #include <sys/vnode.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
57 dm_target_linear_init(dm_dev_t * dmv, void **target_config, char *params)
58 {
59 	dm_target_linear_config_t *tlc;
60 	dm_pdev_t *dmp;
61 
62 	char **ap, *argv[3];
63 
64 	if (params == NULL)
65 		return EINVAL;
66 
67 	/*
68 	 * Parse a string, containing tokens delimited by white space,
69 	 * into an argument vector
70 	 */
71 	for (ap = argv; ap < &argv[2] &&
72 	    (*ap = strsep(&params, " \t")) != NULL;) {
73 		if (**ap != '\0')
74 			ap++;
75 	}
76 
77 	aprint_debug("Linear target init function called %s--%s!!\n",
78 	    argv[0], argv[1]);
79 
80 	/* Insert dmp to global pdev list */
81 	if ((dmp = dm_pdev_insert(argv[0])) == NULL)
82 		return ENOENT;
83 
84 	if ((tlc = kmem_alloc(sizeof(dm_target_linear_config_t), KM_SLEEP))
85 	    == NULL)
86 		return ENOMEM;
87 
88 	tlc->pdev = dmp;
89 	tlc->offset = 0;	/* default settings */
90 
91 	/* Check user input if it is not leave offset as 0. */
92 	tlc->offset = atoi(argv[1]);
93 
94 	*target_config = tlc;
95 
96 	dmv->dev_type = DM_LINEAR_DEV;
97 
98 	return 0;
99 }
100 /*
101  * Status routine is called to get params string, which is target
102  * specific. When dm_table_status_ioctl is called with flag
103  * DM_STATUS_TABLE_FLAG I have to sent params string back.
104  */
105 char *
106 dm_target_linear_status(void *target_config)
107 {
108 	dm_target_linear_config_t *tlc;
109 	char *params;
110 	tlc = target_config;
111 
112 	aprint_debug("Linear target status function called\n");
113 
114 	if ((params = kmem_alloc(DM_MAX_PARAMS_SIZE, KM_NOSLEEP)) == NULL)
115 		return NULL;
116 
117 	aprint_normal("%s %" PRIu64, tlc->pdev->name, tlc->offset);
118 	snprintf(params, DM_MAX_PARAMS_SIZE, "%s %" PRIu64,
119 	    tlc->pdev->name, tlc->offset);
120 
121 	return params;
122 }
123 /*
124  * Do IO operation, called from dmstrategy routine.
125  */
126 int
127 dm_target_linear_strategy(dm_table_entry_t * table_en, struct buf * bp)
128 {
129 	dm_target_linear_config_t *tlc;
130 
131 	tlc = table_en->target_config;
132 
133 /*	printf("Linear target read function called %" PRIu64 "!!\n",
134 	tlc->offset);*/
135 
136 	bp->b_blkno += tlc->offset;
137 
138 	VOP_STRATEGY(tlc->pdev->pdev_vnode, bp);
139 
140 	return 0;
141 
142 }
143 /*
144  * Sync underlying disk caches.
145  */
146 int
147 dm_target_linear_sync(dm_table_entry_t * table_en)
148 {
149 	int cmd;
150 	dm_target_linear_config_t *tlc;
151 
152 	tlc = table_en->target_config;
153 
154 	cmd = 1;
155 
156 	return VOP_IOCTL(tlc->pdev->pdev_vnode,  DIOCCACHESYNC, &cmd,
157 	    FREAD|FWRITE, kauth_cred_get());
158 }
159 /*
160  * Destroy target specific data. Decrement table pdevs.
161  */
162 int
163 dm_target_linear_destroy(dm_table_entry_t * table_en)
164 {
165 	dm_target_linear_config_t *tlc;
166 
167 	/*
168 	 * Destroy function is called for every target even if it
169 	 * doesn't have target_config.
170 	 */
171 
172 	if (table_en->target_config == NULL)
173 		return 0;
174 
175 	tlc = table_en->target_config;
176 
177 	/* Decrement pdev ref counter if 0 remove it */
178 	dm_pdev_decr(tlc->pdev);
179 
180 	/* Unbusy target so we can unload it */
181 	dm_target_unbusy(table_en->target);
182 
183 	kmem_free(table_en->target_config, sizeof(dm_target_linear_config_t));
184 
185 	table_en->target_config = NULL;
186 
187 	return 0;
188 }
189 /* Add this target pdev dependiences to prop_array_t */
190 int
191 dm_target_linear_deps(dm_table_entry_t * table_en, prop_array_t prop_array)
192 {
193 	dm_target_linear_config_t *tlc;
194 	struct vattr va;
195 
196 	int error;
197 
198 	if (table_en->target_config == NULL)
199 		return ENOENT;
200 
201 	tlc = table_en->target_config;
202 
203 	if ((error = VOP_GETATTR(tlc->pdev->pdev_vnode, &va, curlwp->l_cred)) != 0)
204 		return error;
205 
206 	prop_array_add_uint64(prop_array, (uint64_t) va.va_rdev);
207 
208 	return 0;
209 }
210 /*
211  * Register upcall device.
212  * Linear target doesn't need any upcall devices but other targets like
213  * mirror, snapshot, multipath, stripe will use this functionality.
214  */
215 int
216 dm_target_linear_upcall(dm_table_entry_t * table_en, struct buf * bp)
217 {
218 	return 0;
219 }
220 /*
221  * Transform char s to uint64_t offset number.
222  */
223 uint64_t
224 atoi(const char *s)
225 {
226 	uint64_t n;
227 	n = 0;
228 
229 	while (*s != '\0') {
230 		if (!isdigit(*s))
231 			break;
232 
233 		n = (10 * n) + (*s - '0');
234 		s++;
235 	}
236 
237 	return n;
238 }
239