xref: /netbsd-src/sys/dev/dm/dm.h (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*        $NetBSD: dm.h,v 1.18 2010/05/18 15:10:41 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 #ifndef _DM_DEV_H_
33 #define _DM_DEV_H_
34 
35 
36 #ifdef _KERNEL
37 
38 #include <sys/errno.h>
39 
40 #include <sys/atomic.h>
41 #include <sys/fcntl.h>
42 #include <sys/condvar.h>
43 #include <sys/kauth.h>
44 #include <sys/mutex.h>
45 #include <sys/rwlock.h>
46 #include <sys/queue.h>
47 
48 #include <sys/device.h>
49 #include <sys/disklabel.h>
50 
51 #include <prop/proplib.h>
52 
53 #define DM_MAX_TYPE_NAME 16
54 #define DM_NAME_LEN 128
55 #define DM_UUID_LEN 129
56 
57 #define DM_VERSION_MAJOR	4
58 #define DM_VERSION_MINOR	16
59 
60 #define DM_VERSION_PATCHLEVEL	0
61 
62 /*** Internal device-mapper structures ***/
63 
64 /*
65  * A table entry describes a physical range of the logical volume.
66  */
67 #define MAX_TARGET_STRING_LEN 32
68 
69 /*
70  * A device mapper table is a list of physical ranges plus the mapping target
71  * applied to them.
72  */
73 
74 typedef struct dm_table_entry {
75 	struct dm_dev *dm_dev;		/* backlink */
76 	uint64_t start;
77 	uint64_t length;
78 
79 	struct dm_target *target;      /* Link to table target. */
80 	void *target_config;           /* Target specific data. */
81 	SLIST_ENTRY(dm_table_entry) next;
82 } dm_table_entry_t;
83 
84 SLIST_HEAD(dm_table, dm_table_entry);
85 
86 typedef struct dm_table dm_table_t;
87 
88 typedef struct dm_table_head {
89 	/* Current active table is selected with this. */
90 	int cur_active_table;
91 	struct dm_table tables[2];
92 
93 	kmutex_t   table_mtx;
94 	kcondvar_t table_cv; /*IO waiting cv */
95 
96 	uint32_t io_cnt;
97 } dm_table_head_t;
98 
99 #define MAX_DEV_NAME 32
100 
101 /*
102  * This structure is used to store opened vnodes for disk with name.
103  * I need this because devices can be opened only once, but I can
104  * have more then one device on one partition.
105  */
106 
107 typedef struct dm_pdev {
108 	char name[MAX_DEV_NAME];
109 
110 	struct vnode *pdev_vnode;
111 	int ref_cnt; /* reference counter for users ofthis pdev */
112 
113 	SLIST_ENTRY(dm_pdev) next_pdev;
114 } dm_pdev_t;
115 
116 /*
117  * This structure is called for every device-mapper device.
118  * It points to SLIST of device tables and mirrored, snapshoted etc. devices.
119  */
120 TAILQ_HEAD(dm_dev_head, dm_dev) dm_devs;
121 
122 typedef struct dm_dev {
123 	char name[DM_NAME_LEN];
124 	char uuid[DM_UUID_LEN];
125 
126 	device_t devt; /* pointer to autoconf device_t structure */
127 	uint64_t minor;
128 	uint32_t flags; /* store communication protocol flags */
129 
130 	kmutex_t dev_mtx; /* mutex for generall device lock */
131 	kcondvar_t dev_cv; /* cv for between ioctl synchronisation */
132 
133 	uint32_t event_nr;
134 	uint32_t ref_cnt;
135 
136 	uint32_t dev_type;
137 
138 	dm_table_head_t table_head;
139 
140 	struct dm_dev_head upcalls;
141 
142 	struct disk *diskp;
143 	kmutex_t diskp_mtx;
144 
145 	TAILQ_ENTRY(dm_dev) next_upcall; /* LIST of mirrored, snapshoted devices. */
146 
147 	TAILQ_ENTRY(dm_dev) next_devlist; /* Major device list. */
148 } dm_dev_t;
149 
150 /* Device types used for upcalls */
151 #define DM_ZERO_DEV            (1 << 0)
152 #define DM_ERROR_DEV           (1 << 1)
153 #define DM_LINEAR_DEV          (1 << 2)
154 #define DM_MIRROR_DEV          (1 << 3)
155 #define DM_STRIPE_DEV          (1 << 4)
156 #define DM_SNAPSHOT_DEV        (1 << 5)
157 #define DM_SNAPSHOT_ORIG_DEV   (1 << 6)
158 #define DM_SPARE_DEV           (1 << 7)
159 /* Set this device type only during dev remove ioctl. */
160 #define DM_DELETING_DEV        (1 << 8)
161 
162 
163 /* for zero, error : dm_target->target_config == NULL */
164 
165 /*
166  * Target config is initiated with target_init function.
167  */
168 
169 /* for linear : */
170 typedef struct target_linear_config {
171 	dm_pdev_t *pdev;
172 	uint64_t offset;
173 } dm_target_linear_config_t;
174 
175 /* for stripe : */
176 typedef struct target_stripe_config {
177 #define MAX_STRIPES 2
178 	struct target_linear_config stripe_devs[MAX_STRIPES];
179 	uint8_t stripe_num;
180 	uint64_t stripe_chunksize;
181 	size_t params_len;
182 } dm_target_stripe_config_t;
183 
184 /* for mirror : */
185 typedef struct target_mirror_config {
186 #define MAX_MIRROR_COPIES 4
187 	dm_pdev_t *orig;
188 	dm_pdev_t *copies[MAX_MIRROR_COPIES];
189 
190 	/* copied blocks bitmaps administration etc*/
191 	dm_pdev_t *log_pdev;	/* for administration */
192 	uint64_t log_regionsize;	/* blocksize of mirror */
193 
194 	/* list of parts that still need copied etc.; run length encoded? */
195 } dm_target_mirror_config_t;
196 
197 
198 /* for snapshot : */
199 typedef struct target_snapshot_config {
200 	dm_pdev_t *tsc_snap_dev;
201 	/* cow dev is set only for persistent snapshot devices */
202 	dm_pdev_t *tsc_cow_dev;
203 
204 	uint64_t tsc_chunk_size;
205 	uint32_t tsc_persistent_dev;
206 } dm_target_snapshot_config_t;
207 
208 /* for snapshot-origin devices */
209 typedef struct target_snapshot_origin_config {
210 	dm_pdev_t *tsoc_real_dev;
211 	/* list of snapshots ? */
212 } dm_target_snapshot_origin_config_t;
213 
214 /* constant dm_target structures for error, zero, linear, stripes etc. */
215 typedef struct dm_target {
216 	char name[DM_MAX_TYPE_NAME];
217 	/* Initialize target_config area */
218 	int (*init)(dm_dev_t *, void **, char *);
219 
220 	/* Destroy target_config area */
221 	int (*destroy)(dm_table_entry_t *);
222 
223 	int (*deps) (dm_table_entry_t *, prop_array_t);
224 	/*
225 	 * Status routine is called to get params string, which is target
226 	 * specific. When dm_table_status_ioctl is called with flag
227 	 * DM_STATUS_TABLE_FLAG I have to sent params string back.
228 	 */
229 	char * (*status)(void *);
230 	int (*strategy)(dm_table_entry_t *, struct buf *);
231 	int (*sync)(dm_table_entry_t *);
232 	int (*upcall)(dm_table_entry_t *, struct buf *);
233 
234 	uint32_t version[3];
235 	int ref_cnt;
236 
237 	TAILQ_ENTRY(dm_target) dm_target_next;
238 } dm_target_t;
239 
240 /* Interface structures */
241 
242 /*
243  * This structure is used to translate command sent to kernel driver in
244  * <key>command</key>
245  * <value></value>
246  * to function which I can call.
247  */
248 struct cmd_function {
249 	const char *cmd;
250 	int  (*fn)(prop_dictionary_t);
251 };
252 
253 /* device-mapper */
254 void dmgetproperties(struct disk *, dm_table_head_t *);
255 
256 /* dm_ioctl.c */
257 int dm_dev_create_ioctl(prop_dictionary_t);
258 int dm_dev_list_ioctl(prop_dictionary_t);
259 int dm_dev_remove_ioctl(prop_dictionary_t);
260 int dm_dev_rename_ioctl(prop_dictionary_t);
261 int dm_dev_resume_ioctl(prop_dictionary_t);
262 int dm_dev_status_ioctl(prop_dictionary_t);
263 int dm_dev_suspend_ioctl(prop_dictionary_t);
264 
265 int dm_check_version(prop_dictionary_t);
266 int dm_get_version_ioctl(prop_dictionary_t);
267 int dm_list_versions_ioctl(prop_dictionary_t);
268 
269 int dm_table_clear_ioctl(prop_dictionary_t);
270 int dm_table_deps_ioctl(prop_dictionary_t);
271 int dm_table_load_ioctl(prop_dictionary_t);
272 int dm_table_status_ioctl(prop_dictionary_t);
273 
274 /* dm_target.c */
275 dm_target_t* dm_target_alloc(const char *);
276 dm_target_t* dm_target_autoload(const char *);
277 int dm_target_destroy(void);
278 int dm_target_insert(dm_target_t *);
279 prop_array_t dm_target_prop_list(void);
280 dm_target_t* dm_target_lookup(const char *);
281 int dm_target_rem(char *);
282 void dm_target_unbusy(dm_target_t *);
283 void dm_target_busy(dm_target_t *);
284 
285 /* XXX temporally add */
286 int dm_target_init(void);
287 
288 #define DM_MAX_PARAMS_SIZE 1024
289 
290 /* dm_target_linear.c */
291 int dm_target_linear_init(dm_dev_t *, void**, char *);
292 char * dm_target_linear_status(void *);
293 int dm_target_linear_strategy(dm_table_entry_t *, struct buf *);
294 int dm_target_linear_sync(dm_table_entry_t *);
295 int dm_target_linear_deps(dm_table_entry_t *, prop_array_t);
296 int dm_target_linear_destroy(dm_table_entry_t *);
297 int dm_target_linear_upcall(dm_table_entry_t *, struct buf *);
298 
299 /* Generic function used to convert char to string */
300 uint64_t atoi(const char *);
301 
302 /* dm_target_stripe.c */
303 int dm_target_stripe_init(dm_dev_t *, void**, char *);
304 char * dm_target_stripe_status(void *);
305 int dm_target_stripe_strategy(dm_table_entry_t *, struct buf *);
306 int dm_target_stripe_sync(dm_table_entry_t *);
307 int dm_target_stripe_deps(dm_table_entry_t *, prop_array_t);
308 int dm_target_stripe_destroy(dm_table_entry_t *);
309 int dm_target_stripe_upcall(dm_table_entry_t *, struct buf *);
310 
311 /* dm_table.c  */
312 #define DM_TABLE_ACTIVE 0
313 #define DM_TABLE_INACTIVE 1
314 
315 int dm_table_destroy(dm_table_head_t *, uint8_t);
316 uint64_t dm_table_size(dm_table_head_t *);
317 dm_table_t * dm_table_get_entry(dm_table_head_t *, uint8_t);
318 int dm_table_get_target_count(dm_table_head_t *, uint8_t);
319 void dm_table_release(dm_table_head_t *, uint8_t s);
320 void dm_table_switch_tables(dm_table_head_t *);
321 void dm_table_head_init(dm_table_head_t *);
322 void dm_table_head_destroy(dm_table_head_t *);
323 
324 /* dm_dev.c */
325 dm_dev_t* dm_dev_alloc(void);
326 void dm_dev_busy(dm_dev_t *);
327 int dm_dev_destroy(void);
328 dm_dev_t* dm_dev_detach(device_t);
329 int dm_dev_free(dm_dev_t *);
330 int dm_dev_init(void);
331 int dm_dev_insert(dm_dev_t *);
332 dm_dev_t* dm_dev_lookup(const char *, const char *, int);
333 prop_array_t dm_dev_prop_list(void);
334 dm_dev_t* dm_dev_rem(const char *, const char *, int);
335 /*int dm_dev_test_minor(int);*/
336 void dm_dev_unbusy(dm_dev_t *);
337 
338 /* dm_pdev.c */
339 int dm_pdev_decr(dm_pdev_t *);
340 int dm_pdev_destroy(void);
341 int dm_pdev_init(void);
342 dm_pdev_t* dm_pdev_insert(const char *);
343 
344 #endif /*_KERNEL*/
345 
346 #endif /*_DM_DEV_H_*/
347