xref: /netbsd-src/sys/dev/dm/dm.h (revision 4e6df137e8e14049b5a701d249962c480449c141)
1 /*        $NetBSD: dm.h,v 1.17 2009/12/29 23:37:48 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/condvar.h>
42 #include <sys/mutex.h>
43 #include <sys/rwlock.h>
44 #include <sys/queue.h>
45 
46 #include <sys/device.h>
47 #include <sys/disklabel.h>
48 
49 #include <prop/proplib.h>
50 
51 #define DM_MAX_TYPE_NAME 16
52 #define DM_NAME_LEN 128
53 #define DM_UUID_LEN 129
54 
55 #define DM_VERSION_MAJOR	4
56 #define DM_VERSION_MINOR	16
57 
58 #define DM_VERSION_PATCHLEVEL	0
59 
60 /*** Internal device-mapper structures ***/
61 
62 /*
63  * A table entry describes a physical range of the logical volume.
64  */
65 #define MAX_TARGET_STRING_LEN 32
66 
67 /*
68  * A device mapper table is a list of physical ranges plus the mapping target
69  * applied to them.
70  */
71 
72 typedef struct dm_table_entry {
73 	struct dm_dev *dm_dev;		/* backlink */
74 	uint64_t start;
75 	uint64_t length;
76 
77 	struct dm_target *target;      /* Link to table target. */
78 	void *target_config;           /* Target specific data. */
79 	SLIST_ENTRY(dm_table_entry) next;
80 } dm_table_entry_t;
81 
82 SLIST_HEAD(dm_table, dm_table_entry);
83 
84 typedef struct dm_table dm_table_t;
85 
86 typedef struct dm_table_head {
87 	/* Current active table is selected with this. */
88 	int cur_active_table;
89 	struct dm_table tables[2];
90 
91 	kmutex_t   table_mtx;
92 	kcondvar_t table_cv; /*IO waiting cv */
93 
94 	uint32_t io_cnt;
95 } dm_table_head_t;
96 
97 #define MAX_DEV_NAME 32
98 
99 /*
100  * This structure is used to store opened vnodes for disk with name.
101  * I need this because devices can be opened only once, but I can
102  * have more then one device on one partition.
103  */
104 
105 typedef struct dm_pdev {
106 	char name[MAX_DEV_NAME];
107 
108 	struct vnode *pdev_vnode;
109 	int ref_cnt; /* reference counter for users ofthis pdev */
110 
111 	SLIST_ENTRY(dm_pdev) next_pdev;
112 } dm_pdev_t;
113 
114 /*
115  * This structure is called for every device-mapper device.
116  * It points to SLIST of device tables and mirrored, snapshoted etc. devices.
117  */
118 TAILQ_HEAD(dm_dev_head, dm_dev) dm_devs;
119 
120 typedef struct dm_dev {
121 	char name[DM_NAME_LEN];
122 	char uuid[DM_UUID_LEN];
123 
124 	device_t devt; /* pointer to autoconf device_t structure */
125 	uint64_t minor;
126 	uint32_t flags; /* store communication protocol flags */
127 
128 	kmutex_t dev_mtx; /* mutex for generall device lock */
129 	kcondvar_t dev_cv; /* cv for between ioctl synchronisation */
130 
131 	uint32_t event_nr;
132 	uint32_t ref_cnt;
133 
134 	uint32_t dev_type;
135 
136 	dm_table_head_t table_head;
137 
138 	struct dm_dev_head upcalls;
139 
140 	struct disk *diskp;
141 	kmutex_t diskp_mtx;
142 
143 	TAILQ_ENTRY(dm_dev) next_upcall; /* LIST of mirrored, snapshoted devices. */
144 
145 	TAILQ_ENTRY(dm_dev) next_devlist; /* Major device list. */
146 } dm_dev_t;
147 
148 /* Device types used for upcalls */
149 #define DM_ZERO_DEV            (1 << 0)
150 #define DM_ERROR_DEV           (1 << 1)
151 #define DM_LINEAR_DEV          (1 << 2)
152 #define DM_MIRROR_DEV          (1 << 3)
153 #define DM_STRIPE_DEV          (1 << 4)
154 #define DM_SNAPSHOT_DEV        (1 << 5)
155 #define DM_SNAPSHOT_ORIG_DEV   (1 << 6)
156 #define DM_SPARE_DEV           (1 << 7)
157 /* Set this device type only during dev remove ioctl. */
158 #define DM_DELETING_DEV        (1 << 8)
159 
160 
161 /* for zero, error : dm_target->target_config == NULL */
162 
163 /*
164  * Target config is initiated with target_init function.
165  */
166 
167 /* for linear : */
168 typedef struct target_linear_config {
169 	dm_pdev_t *pdev;
170 	uint64_t offset;
171 } dm_target_linear_config_t;
172 
173 /* for stripe : */
174 typedef struct target_stripe_config {
175 #define MAX_STRIPES 2
176 	struct target_linear_config stripe_devs[MAX_STRIPES];
177 	uint8_t stripe_num;
178 	uint64_t stripe_chunksize;
179 	size_t params_len;
180 } dm_target_stripe_config_t;
181 
182 /* for mirror : */
183 typedef struct target_mirror_config {
184 #define MAX_MIRROR_COPIES 4
185 	dm_pdev_t *orig;
186 	dm_pdev_t *copies[MAX_MIRROR_COPIES];
187 
188 	/* copied blocks bitmaps administration etc*/
189 	dm_pdev_t *log_pdev;	/* for administration */
190 	uint64_t log_regionsize;	/* blocksize of mirror */
191 
192 	/* list of parts that still need copied etc.; run length encoded? */
193 } dm_target_mirror_config_t;
194 
195 
196 /* for snapshot : */
197 typedef struct target_snapshot_config {
198 	dm_pdev_t *tsc_snap_dev;
199 	/* cow dev is set only for persistent snapshot devices */
200 	dm_pdev_t *tsc_cow_dev;
201 
202 	uint64_t tsc_chunk_size;
203 	uint32_t tsc_persistent_dev;
204 } dm_target_snapshot_config_t;
205 
206 /* for snapshot-origin devices */
207 typedef struct target_snapshot_origin_config {
208 	dm_pdev_t *tsoc_real_dev;
209 	/* list of snapshots ? */
210 } dm_target_snapshot_origin_config_t;
211 
212 /* constant dm_target structures for error, zero, linear, stripes etc. */
213 typedef struct dm_target {
214 	char name[DM_MAX_TYPE_NAME];
215 	/* Initialize target_config area */
216 	int (*init)(dm_dev_t *, void **, char *);
217 
218 	/* Destroy target_config area */
219 	int (*destroy)(dm_table_entry_t *);
220 
221 	int (*deps) (dm_table_entry_t *, prop_array_t);
222 	/*
223 	 * Status routine is called to get params string, which is target
224 	 * specific. When dm_table_status_ioctl is called with flag
225 	 * DM_STATUS_TABLE_FLAG I have to sent params string back.
226 	 */
227 	char * (*status)(void *);
228 	int (*strategy)(dm_table_entry_t *, struct buf *);
229 	int (*upcall)(dm_table_entry_t *, struct buf *);
230 
231 	uint32_t version[3];
232 	int ref_cnt;
233 
234 	TAILQ_ENTRY(dm_target) dm_target_next;
235 } dm_target_t;
236 
237 /* Interface structures */
238 
239 /*
240  * This structure is used to translate command sent to kernel driver in
241  * <key>command</key>
242  * <value></value>
243  * to function which I can call.
244  */
245 struct cmd_function {
246 	const char *cmd;
247 	int  (*fn)(prop_dictionary_t);
248 };
249 
250 /* device-mapper */
251 void dmgetproperties(struct disk *, dm_table_head_t *);
252 
253 /* dm_ioctl.c */
254 int dm_dev_create_ioctl(prop_dictionary_t);
255 int dm_dev_list_ioctl(prop_dictionary_t);
256 int dm_dev_remove_ioctl(prop_dictionary_t);
257 int dm_dev_rename_ioctl(prop_dictionary_t);
258 int dm_dev_resume_ioctl(prop_dictionary_t);
259 int dm_dev_status_ioctl(prop_dictionary_t);
260 int dm_dev_suspend_ioctl(prop_dictionary_t);
261 
262 int dm_check_version(prop_dictionary_t);
263 int dm_get_version_ioctl(prop_dictionary_t);
264 int dm_list_versions_ioctl(prop_dictionary_t);
265 
266 int dm_table_clear_ioctl(prop_dictionary_t);
267 int dm_table_deps_ioctl(prop_dictionary_t);
268 int dm_table_load_ioctl(prop_dictionary_t);
269 int dm_table_status_ioctl(prop_dictionary_t);
270 
271 /* dm_target.c */
272 dm_target_t* dm_target_alloc(const char *);
273 dm_target_t* dm_target_autoload(const char *);
274 int dm_target_destroy(void);
275 int dm_target_insert(dm_target_t *);
276 prop_array_t dm_target_prop_list(void);
277 dm_target_t* dm_target_lookup(const char *);
278 int dm_target_rem(char *);
279 void dm_target_unbusy(dm_target_t *);
280 void dm_target_busy(dm_target_t *);
281 
282 /* XXX temporally add */
283 int dm_target_init(void);
284 
285 #define DM_MAX_PARAMS_SIZE 1024
286 
287 /* dm_target_zero.c */
288 int dm_target_zero_init(dm_dev_t *, void**,  char *);
289 char * dm_target_zero_status(void *);
290 int dm_target_zero_strategy(dm_table_entry_t *, struct buf *);
291 int dm_target_zero_destroy(dm_table_entry_t *);
292 int dm_target_zero_deps(dm_table_entry_t *, prop_array_t);
293 int dm_target_zero_upcall(dm_table_entry_t *, struct buf *);
294 
295 /* dm_target_error.c */
296 int dm_target_error_init(dm_dev_t *, void**, char *);
297 char * dm_target_error_status(void *);
298 int dm_target_error_strategy(dm_table_entry_t *, struct buf *);
299 int dm_target_error_deps(dm_table_entry_t *, prop_array_t);
300 int dm_target_error_destroy(dm_table_entry_t *);
301 int dm_target_error_upcall(dm_table_entry_t *, struct buf *);
302 
303 /* dm_target_linear.c */
304 int dm_target_linear_init(dm_dev_t *, void**, char *);
305 char * dm_target_linear_status(void *);
306 int dm_target_linear_strategy(dm_table_entry_t *, struct buf *);
307 int dm_target_linear_deps(dm_table_entry_t *, prop_array_t);
308 int dm_target_linear_destroy(dm_table_entry_t *);
309 int dm_target_linear_upcall(dm_table_entry_t *, struct buf *);
310 
311 /* Generic function used to convert char to string */
312 uint64_t atoi(const char *);
313 
314 /* dm_target_mirror.c */
315 int dm_target_mirror_init(dm_dev_t *, void**, char *);
316 char * dm_target_mirror_status(void *);
317 int dm_target_mirror_strategy(dm_table_entry_t *, struct buf *);
318 int dm_target_mirror_deps(dm_table_entry_t *, prop_array_t);
319 int dm_target_mirror_destroy(dm_table_entry_t *);
320 int dm_target_mirror_upcall(dm_table_entry_t *, struct buf *);
321 
322 /* dm_target_stripe.c */
323 int dm_target_stripe_init(dm_dev_t *, void**, char *);
324 char * dm_target_stripe_status(void *);
325 int dm_target_stripe_strategy(dm_table_entry_t *, struct buf *);
326 int dm_target_stripe_deps(dm_table_entry_t *, prop_array_t);
327 int dm_target_stripe_destroy(dm_table_entry_t *);
328 int dm_target_stripe_upcall(dm_table_entry_t *, struct buf *);
329 
330 /* dm_target_snapshot.c */
331 int dm_target_snapshot_init(dm_dev_t *, void**, char *);
332 char * dm_target_snapshot_status(void *);
333 int dm_target_snapshot_strategy(dm_table_entry_t *, struct buf *);
334 int dm_target_snapshot_deps(dm_table_entry_t *, prop_array_t);
335 int dm_target_snapshot_destroy(dm_table_entry_t *);
336 int dm_target_snapshot_upcall(dm_table_entry_t *, struct buf *);
337 
338 /* dm snapshot origin driver */
339 int dm_target_snapshot_orig_init(dm_dev_t *, void**, char *);
340 char * dm_target_snapshot_orig_status(void *);
341 int dm_target_snapshot_orig_strategy(dm_table_entry_t *, struct buf *);
342 int dm_target_snapshot_orig_deps(dm_table_entry_t *, prop_array_t);
343 int dm_target_snapshot_orig_destroy(dm_table_entry_t *);
344 int dm_target_snapshot_orig_upcall(dm_table_entry_t *, struct buf *);
345 
346 /* dm_table.c  */
347 #define DM_TABLE_ACTIVE 0
348 #define DM_TABLE_INACTIVE 1
349 
350 int dm_table_destroy(dm_table_head_t *, uint8_t);
351 uint64_t dm_table_size(dm_table_head_t *);
352 dm_table_t * dm_table_get_entry(dm_table_head_t *, uint8_t);
353 int dm_table_get_target_count(dm_table_head_t *, uint8_t);
354 void dm_table_release(dm_table_head_t *, uint8_t s);
355 void dm_table_switch_tables(dm_table_head_t *);
356 void dm_table_head_init(dm_table_head_t *);
357 void dm_table_head_destroy(dm_table_head_t *);
358 
359 /* dm_dev.c */
360 dm_dev_t* dm_dev_alloc(void);
361 void dm_dev_busy(dm_dev_t *);
362 int dm_dev_destroy(void);
363 dm_dev_t* dm_dev_detach(device_t);
364 int dm_dev_free(dm_dev_t *);
365 int dm_dev_init(void);
366 int dm_dev_insert(dm_dev_t *);
367 dm_dev_t* dm_dev_lookup(const char *, const char *, int);
368 prop_array_t dm_dev_prop_list(void);
369 dm_dev_t* dm_dev_rem(const char *, const char *, int);
370 /*int dm_dev_test_minor(int);*/
371 void dm_dev_unbusy(dm_dev_t *);
372 
373 /* dm_pdev.c */
374 int dm_pdev_decr(dm_pdev_t *);
375 int dm_pdev_destroy(void);
376 int dm_pdev_init(void);
377 dm_pdev_t* dm_pdev_insert(const char *);
378 
379 #endif /*_KERNEL*/
380 
381 #endif /*_DM_DEV_H_*/
382