xref: /netbsd-src/sys/dev/dm/dm.h (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*        $NetBSD: dm.h,v 1.6 2009/01/02 11:03:24 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 #define DM_MAX_TYPE_NAME 16
47 #define DM_NAME_LEN 128
48 #define DM_UUID_LEN 129
49 
50 #define DM_VERSION_MAJOR	4
51 #define DM_VERSION_MINOR	13
52 #define DM_VERSION_PATCHLEVEL	0
53 
54 /*** Internal device-mapper structures ***/
55 
56 /*
57  * A table entry describes a physical range of the logical volume.
58  */
59 #define MAX_TARGET_STRING_LEN 32
60 
61 /*
62  * A device mapper table is a list of physical ranges plus the mapping target
63  * applied to them.
64  */
65 
66 typedef struct dm_table_entry {
67 	struct dm_dev *dm_dev;		/* backlink */
68 	uint64_t start;
69 	uint64_t length;
70 
71 	struct dm_target *target;      /* Link to table target. */
72 	void *target_config;           /* Target specific data. */
73 	SLIST_ENTRY(dm_table_entry) next;
74 } dm_table_entry_t;
75 
76 SLIST_HEAD(dm_table, dm_table_entry);
77 
78 typedef struct dm_table dm_table_t;
79 
80 typedef struct dm_table_head {
81 	/* Current active table is selected with this. */
82 	int cur_active_table;
83 	struct dm_table tables[2];
84 
85 	kmutex_t   table_mtx;
86 	kcondvar_t table_cv; /*IO waiting cv */
87 
88 	uint32_t io_cnt;
89 } dm_table_head_t;
90 
91 #define MAX_DEV_NAME 32
92 
93 /*
94  * This structure is used to store opened vnodes for disk with name.
95  * I need this because devices can be opened only once, but I can
96  * have more then one device on one partition.
97  */
98 
99 typedef struct dm_pdev {
100 	char name[MAX_DEV_NAME];
101 
102 	struct vnode *pdev_vnode;
103 	int ref_cnt; /* reference counter for users ofthis pdev */
104 
105 	SLIST_ENTRY(dm_pdev) next_pdev;
106 } dm_pdev_t;
107 
108 /*
109  * This structure is called for every device-mapper device.
110  * It points to SLIST of device tables and mirrored, snapshoted etc. devices.
111  */
112 TAILQ_HEAD(dm_dev_head, dm_dev) dm_devs;
113 
114 typedef struct dm_dev {
115 	char name[DM_NAME_LEN];
116 	char uuid[DM_UUID_LEN];
117 
118 	int minor;
119 	uint32_t flags; /* store communication protocol flags */
120 
121 	kmutex_t dev_mtx; /* mutex for generall device lock */
122 	kcondvar_t dev_cv; /* cv for between ioctl synchronisation */
123 
124 	uint32_t event_nr;
125 	uint32_t ref_cnt;
126 
127 	uint32_t dev_type;
128 
129 	dm_table_head_t table_head;
130 
131 	struct dm_dev_head upcalls;
132 
133 	struct disklabel *dk_label;    /* Disklabel for this table. */
134 
135 	TAILQ_ENTRY(dm_dev) next_upcall; /* LIST of mirrored, snapshoted devices. */
136 
137 	TAILQ_ENTRY(dm_dev) next_devlist; /* Major device list. */
138 } dm_dev_t;
139 
140 /* Device types used for upcalls */
141 #define DM_ZERO_DEV            (1 << 0)
142 #define DM_ERROR_DEV           (1 << 1)
143 #define DM_LINEAR_DEV          (1 << 2)
144 #define DM_MIRROR_DEV          (1 << 3)
145 #define DM_STRIPE_DEV          (1 << 4)
146 #define DM_SNAPSHOT_DEV        (1 << 5)
147 #define DM_SNAPSHOT_ORIG_DEV   (1 << 6)
148 #define DM_SPARE_DEV           (1 << 7)
149 /* Set this device type only during dev remove ioctl. */
150 #define DM_DELETING_DEV        (1 << 8)
151 
152 
153 /* for zero, error : dm_target->target_config == NULL */
154 
155 /*
156  * Target config is initiated with target_init function.
157  */
158 
159 /* for linear : */
160 typedef struct target_linear_config {
161 	dm_pdev_t *pdev;
162 	uint64_t offset;
163 } dm_target_linear_config_t;
164 
165 
166 /* for mirror : */
167 typedef struct target_mirror_config {
168 #define MAX_MIRROR_COPIES 4
169 	dm_pdev_t *orig;
170 	dm_pdev_t *copies[MAX_MIRROR_COPIES];
171 
172 	/* copied blocks bitmaps administration etc*/
173 	dm_pdev_t *log_pdev;	/* for administration */
174 	uint64_t log_regionsize;	/* blocksize of mirror */
175 
176 	/* list of parts that still need copied etc.; run length encoded? */
177 } dm_target_mirror_config_t;
178 
179 
180 /* for snapshot : */
181 typedef struct target_snapshot_config {
182 	dm_pdev_t *tsc_snap_dev;
183 	/* cow dev is set only for persistent snapshot devices */
184 	dm_pdev_t *tsc_cow_dev;
185 
186 	uint64_t tsc_chunk_size;
187 	uint32_t tsc_persistent_dev;
188 } dm_target_snapshot_config_t;
189 
190 /* for snapshot-origin devices */
191 typedef struct target_snapshot_origin_config {
192 	dm_pdev_t *tsoc_real_dev;
193 	/* list of snapshots ? */
194 } dm_target_snapshot_origin_config_t;
195 
196 /* constant dm_target structures for error, zero, linear, stripes etc. */
197 typedef struct dm_target {
198 	char name[DM_MAX_TYPE_NAME];
199 	/* Initialize target_config area */
200 	int (*init)(dm_dev_t *, void **, char *);
201 
202 	/* Destroy target_config area */
203 	int (*destroy)(dm_table_entry_t *);
204 
205 	int (*deps) (dm_table_entry_t *, prop_array_t);
206 	/*
207 	 * Status routine is called to get params string, which is target
208 	 * specific. When dm_table_status_ioctl is called with flag
209 	 * DM_STATUS_TABLE_FLAG I have to sent params string back.
210 	 */
211 	char * (*status)(void *);
212 	int (*strategy)(dm_table_entry_t *, struct buf *);
213 	int (*upcall)(dm_table_entry_t *, struct buf *);
214 
215 	uint32_t version[3];
216 	int ref_cnt;
217 
218 	TAILQ_ENTRY(dm_target) dm_target_next;
219 } dm_target_t;
220 
221 /* Interface structures */
222 
223 /*
224  * This structure is used to translate command sent to kernel driver in
225  * <key>command</key>
226  * <value></value>
227  * to function which I can call.
228  */
229 struct cmd_function {
230 	const char *cmd;
231 	int  (*fn)(prop_dictionary_t);
232 };
233 
234 /* device-mapper */
235 void dmgetdisklabel(struct disklabel *, dm_table_head_t *);
236 
237 /* dm_ioctl.c */
238 int dm_dev_create_ioctl(prop_dictionary_t);
239 int dm_dev_list_ioctl(prop_dictionary_t);
240 int dm_dev_remove_ioctl(prop_dictionary_t);
241 int dm_dev_rename_ioctl(prop_dictionary_t);
242 int dm_dev_resume_ioctl(prop_dictionary_t);
243 int dm_dev_status_ioctl(prop_dictionary_t);
244 int dm_dev_suspend_ioctl(prop_dictionary_t);
245 
246 int dm_check_version(prop_dictionary_t);
247 int dm_get_version_ioctl(prop_dictionary_t);
248 int dm_list_versions_ioctl(prop_dictionary_t);
249 
250 int dm_table_clear_ioctl(prop_dictionary_t);
251 int dm_table_deps_ioctl(prop_dictionary_t);
252 int dm_table_load_ioctl(prop_dictionary_t);
253 int dm_table_status_ioctl(prop_dictionary_t);
254 
255 /* dm_target.c */
256 dm_target_t* dm_target_alloc(const char *);
257 int dm_target_destroy(void);
258 int dm_target_insert(dm_target_t *);
259 prop_array_t dm_target_prop_list(void);
260 dm_target_t* dm_target_lookup(const char *);
261 int dm_target_rem(char *);
262 void dm_target_unbusy(dm_target_t *);
263 void dm_target_busy(dm_target_t *);
264 
265 /* XXX temporally add */
266 int dm_target_init(void);
267 
268 /* dm_target_zero.c */
269 int dm_target_zero_init(dm_dev_t *, void**,  char *);
270 char * dm_target_zero_status(void *);
271 int dm_target_zero_strategy(dm_table_entry_t *, struct buf *);
272 int dm_target_zero_destroy(dm_table_entry_t *);
273 int dm_target_zero_deps(dm_table_entry_t *, prop_array_t);
274 int dm_target_zero_upcall(dm_table_entry_t *, struct buf *);
275 
276 /* dm_target_error.c */
277 int dm_target_error_init(dm_dev_t *, void**, char *);
278 char * dm_target_error_status(void *);
279 int dm_target_error_strategy(dm_table_entry_t *, struct buf *);
280 int dm_target_error_deps(dm_table_entry_t *, prop_array_t);
281 int dm_target_error_destroy(dm_table_entry_t *);
282 int dm_target_error_upcall(dm_table_entry_t *, struct buf *);
283 
284 /* dm_target_linear.c */
285 int dm_target_linear_init(dm_dev_t *, void**, char *);
286 char * dm_target_linear_status(void *);
287 int dm_target_linear_strategy(dm_table_entry_t *, struct buf *);
288 int dm_target_linear_deps(dm_table_entry_t *, prop_array_t);
289 int dm_target_linear_destroy(dm_table_entry_t *);
290 int dm_target_linear_upcall(dm_table_entry_t *, struct buf *);
291 
292 /* Generic function used to convert char to string */
293 uint64_t atoi(const char *);
294 
295 /* dm_target_mirror.c */
296 int dm_target_mirror_init(dm_dev_t *, void**, char *);
297 char * dm_target_mirror_status(void *);
298 int dm_target_mirror_strategy(dm_table_entry_t *, struct buf *);
299 int dm_target_mirror_deps(dm_table_entry_t *, prop_array_t);
300 int dm_target_mirror_destroy(dm_table_entry_t *);
301 int dm_target_mirror_upcall(dm_table_entry_t *, struct buf *);
302 
303 /* dm_target_stripe.c */
304 int dm_target_stripe_init(dm_dev_t *, void**, char *);
305 char * dm_target_stripe_status(void *);
306 int dm_target_stripe_strategy(dm_table_entry_t *, struct buf *);
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_target_snapshot.c */
312 int dm_target_snapshot_init(dm_dev_t *, void**, char *);
313 char * dm_target_snapshot_status(void *);
314 int dm_target_snapshot_strategy(dm_table_entry_t *, struct buf *);
315 int dm_target_snapshot_deps(dm_table_entry_t *, prop_array_t);
316 int dm_target_snapshot_destroy(dm_table_entry_t *);
317 int dm_target_snapshot_upcall(dm_table_entry_t *, struct buf *);
318 
319 /* dm snapshot origin driver */
320 int dm_target_snapshot_orig_init(dm_dev_t *, void**, char *);
321 char * dm_target_snapshot_orig_status(void *);
322 int dm_target_snapshot_orig_strategy(dm_table_entry_t *, struct buf *);
323 int dm_target_snapshot_orig_deps(dm_table_entry_t *, prop_array_t);
324 int dm_target_snapshot_orig_destroy(dm_table_entry_t *);
325 int dm_target_snapshot_orig_upcall(dm_table_entry_t *, struct buf *);
326 
327 /* dm_table.c  */
328 #define DM_TABLE_ACTIVE 0
329 #define DM_TABLE_INACTIVE 1
330 
331 int dm_table_destroy(dm_table_head_t *, uint8_t);
332 uint64_t dm_table_size(dm_table_head_t *);
333 dm_table_t * dm_table_get_entry(dm_table_head_t *, uint8_t);
334 int dm_table_get_target_count(dm_table_head_t *, uint8_t);
335 void dm_table_release(dm_table_head_t *, uint8_t s);
336 void dm_table_switch_tables(dm_table_head_t *);
337 void dm_table_head_init(dm_table_head_t *);
338 void dm_table_head_destroy(dm_table_head_t *);
339 
340 /* dm_dev.c */
341 dm_dev_t* dm_dev_alloc(void);
342 void dm_dev_busy(dm_dev_t *);
343 int dm_dev_destroy(void);
344 int dm_dev_free(dm_dev_t *);
345 int dm_dev_init(void);
346 int dm_dev_insert(dm_dev_t *);
347 dm_dev_t* dm_dev_lookup(const char *, const char *, int);
348 prop_array_t dm_dev_prop_list(void);
349 dm_dev_t* dm_dev_rem(const char *, const char *, int);
350 /*int dm_dev_test_minor(int);*/
351 void dm_dev_unbusy(dm_dev_t *);
352 
353 /* dm_pdev.c */
354 int dm_pdev_decr(dm_pdev_t *);
355 int dm_pdev_destroy(void);
356 int dm_pdev_init(void);
357 dm_pdev_t* dm_pdev_insert(const char *);
358 
359 #endif /*_KERNEL*/
360 
361 #endif /*_DM_DEV_H_*/
362