xref: /netbsd-src/sys/dev/dm/dm.h (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*        $NetBSD: dm.h,v 1.25 2013/12/09 09:35:16 wiz 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/disk.h>
50 #include <sys/disklabel.h>
51 
52 #include <prop/proplib.h>
53 
54 #define DM_MAX_TYPE_NAME 16
55 #define DM_NAME_LEN 128
56 #define DM_UUID_LEN 129
57 
58 #define DM_VERSION_MAJOR	4
59 #define DM_VERSION_MINOR	16
60 
61 #define DM_VERSION_PATCHLEVEL	0
62 
63 /*** Internal device-mapper structures ***/
64 
65 /*
66  * A table entry describes a physical range of the logical volume.
67  */
68 #define MAX_TARGET_STRING_LEN 32
69 
70 /*
71  * A device mapper table is a list of physical ranges plus the mapping target
72  * applied to them.
73  */
74 
75 typedef struct dm_table_entry {
76 	struct dm_dev *dm_dev;		/* backlink */
77 	uint64_t start;
78 	uint64_t length;
79 
80 	struct dm_target *target;      /* Link to table target. */
81 	void *target_config;           /* Target specific data. */
82 	SLIST_ENTRY(dm_table_entry) next;
83 } dm_table_entry_t;
84 
85 SLIST_HEAD(dm_table, dm_table_entry);
86 
87 typedef struct dm_table dm_table_t;
88 
89 typedef struct dm_table_head {
90 	/* Current active table is selected with this. */
91 	int cur_active_table;
92 	struct dm_table tables[2];
93 
94 	kmutex_t   table_mtx;
95 	kcondvar_t table_cv; /*IO waiting cv */
96 
97 	uint32_t io_cnt;
98 } dm_table_head_t;
99 
100 #define MAX_DEV_NAME 32
101 
102 /*
103  * This structure is used to store opened vnodes for disk with name.
104  * I need this because devices can be opened only once, but I can
105  * have more than one device on one partition.
106  */
107 
108 typedef struct dm_pdev {
109 	char name[MAX_DEV_NAME];
110 
111 	struct vnode *pdev_vnode;
112 	uint64_t pdev_numsec;
113 	unsigned pdev_secsize;
114 	int ref_cnt; /* reference counter for users ofthis pdev */
115 
116 	SLIST_ENTRY(dm_pdev) next_pdev;
117 } dm_pdev_t;
118 
119 /*
120  * This structure is called for every device-mapper device.
121  * It points to SLIST of device tables and mirrored, snapshoted etc. devices.
122  */
123 TAILQ_HEAD(dm_dev_head, dm_dev);
124 //extern struct dm_dev_head dm_devs;
125 
126 typedef struct dm_dev {
127 	char name[DM_NAME_LEN];
128 	char uuid[DM_UUID_LEN];
129 
130 	device_t devt; /* pointer to autoconf device_t structure */
131 	uint64_t minor; /* Device minor number */
132 	uint32_t flags; /* store communication protocol flags */
133 
134 	kmutex_t dev_mtx; /* mutex for generall device lock */
135 	kcondvar_t dev_cv; /* cv for between ioctl synchronisation */
136 
137 	uint32_t event_nr;
138 	uint32_t ref_cnt;
139 
140 	uint32_t dev_type;
141 
142 	dm_table_head_t table_head;
143 
144 	struct dm_dev_head upcalls;
145 
146 	struct disk *diskp;
147 	kmutex_t diskp_mtx;
148 
149 	TAILQ_ENTRY(dm_dev) next_upcall; /* LIST of mirrored, snapshoted devices. */
150 
151 	TAILQ_ENTRY(dm_dev) next_devlist; /* Major device list. */
152 } dm_dev_t;
153 
154 /* Device types used for upcalls */
155 #define DM_ZERO_DEV            (1 << 0)
156 #define DM_ERROR_DEV           (1 << 1)
157 #define DM_LINEAR_DEV          (1 << 2)
158 #define DM_MIRROR_DEV          (1 << 3)
159 #define DM_STRIPE_DEV          (1 << 4)
160 #define DM_SNAPSHOT_DEV        (1 << 5)
161 #define DM_SNAPSHOT_ORIG_DEV   (1 << 6)
162 #define DM_SPARE_DEV           (1 << 7)
163 /* Set this device type only during dev remove ioctl. */
164 #define DM_DELETING_DEV        (1 << 8)
165 
166 
167 /* for zero, error : dm_target->target_config == NULL */
168 
169 /*
170  * Target config is initiated with target_init function.
171  */
172 
173 /* for linear : */
174 typedef struct target_linear_config {
175 	dm_pdev_t *pdev;
176 	uint64_t offset;
177 	TAILQ_ENTRY(target_linear_config) entries;
178 } dm_target_linear_config_t;
179 
180 /*
181  * Striping devices are stored in a linked list, this might be inefficient
182  * for more than 8 striping devices and can be changed to something more
183  * scalable.
184  * TODO: look for other options than linked list.
185  */
186 TAILQ_HEAD(target_linear_devs, target_linear_config);
187 
188 typedef struct target_linear_devs dm_target_linear_devs_t;
189 
190 /* for stripe : */
191 typedef struct target_stripe_config {
192 #define DM_STRIPE_DEV_OFFSET 2
193 	struct target_linear_devs stripe_devs;
194 	uint8_t stripe_num;
195 	uint64_t stripe_chunksize;
196 	size_t params_len;
197 } dm_target_stripe_config_t;
198 
199 /* for mirror : */
200 typedef struct target_mirror_config {
201 #define MAX_MIRROR_COPIES 4
202 	dm_pdev_t *orig;
203 	dm_pdev_t *copies[MAX_MIRROR_COPIES];
204 
205 	/* copied blocks bitmaps administration etc*/
206 	dm_pdev_t *log_pdev;	/* for administration */
207 	uint64_t log_regionsize;	/* blocksize of mirror */
208 
209 	/* list of parts that still need copied etc.; run length encoded? */
210 } dm_target_mirror_config_t;
211 
212 
213 /* for snapshot : */
214 typedef struct target_snapshot_config {
215 	dm_pdev_t *tsc_snap_dev;
216 	/* cow dev is set only for persistent snapshot devices */
217 	dm_pdev_t *tsc_cow_dev;
218 
219 	uint64_t tsc_chunk_size;
220 	uint32_t tsc_persistent_dev;
221 } dm_target_snapshot_config_t;
222 
223 /* for snapshot-origin devices */
224 typedef struct target_snapshot_origin_config {
225 	dm_pdev_t *tsoc_real_dev;
226 	/* list of snapshots ? */
227 } dm_target_snapshot_origin_config_t;
228 
229 /* constant dm_target structures for error, zero, linear, stripes etc. */
230 typedef struct dm_target {
231 	char name[DM_MAX_TYPE_NAME];
232 	/* Initialize target_config area */
233 	int (*init)(dm_dev_t *, void **, char *);
234 
235 	/* Destroy target_config area */
236 	int (*destroy)(dm_table_entry_t *);
237 
238 	int (*deps) (dm_table_entry_t *, prop_array_t);
239 	/*
240 	 * Status routine is called to get params string, which is target
241 	 * specific. When dm_table_status_ioctl is called with flag
242 	 * DM_STATUS_TABLE_FLAG I have to sent params string back.
243 	 */
244 	char * (*status)(void *);
245 	int (*strategy)(dm_table_entry_t *, struct buf *);
246 	int (*sync)(dm_table_entry_t *);
247 	int (*upcall)(dm_table_entry_t *, struct buf *);
248 	int (*secsize)(dm_table_entry_t *, unsigned *);
249 
250 	uint32_t version[3];
251 	int ref_cnt;
252 
253 	TAILQ_ENTRY(dm_target) dm_target_next;
254 } dm_target_t;
255 
256 /* Interface structures */
257 
258 /*
259  * This structure is used to translate command sent to kernel driver in
260  * <key>command</key>
261  * <value></value>
262  * to function which I can call, and if the command is allowed for
263  * non-superusers.
264  */
265 struct cmd_function {
266 	const char *cmd;
267 	int  (*fn)(prop_dictionary_t);
268 	int  allowed;
269 };
270 
271 /* device-mapper */
272 void dmgetproperties(struct disk *, dm_table_head_t *);
273 
274 /* dm_ioctl.c */
275 int dm_dev_create_ioctl(prop_dictionary_t);
276 int dm_dev_list_ioctl(prop_dictionary_t);
277 int dm_dev_remove_ioctl(prop_dictionary_t);
278 int dm_dev_rename_ioctl(prop_dictionary_t);
279 int dm_dev_resume_ioctl(prop_dictionary_t);
280 int dm_dev_status_ioctl(prop_dictionary_t);
281 int dm_dev_suspend_ioctl(prop_dictionary_t);
282 
283 int dm_check_version(prop_dictionary_t);
284 int dm_get_version_ioctl(prop_dictionary_t);
285 int dm_list_versions_ioctl(prop_dictionary_t);
286 
287 int dm_table_clear_ioctl(prop_dictionary_t);
288 int dm_table_deps_ioctl(prop_dictionary_t);
289 int dm_table_load_ioctl(prop_dictionary_t);
290 int dm_table_status_ioctl(prop_dictionary_t);
291 
292 /* dm_target.c */
293 dm_target_t* dm_target_alloc(const char *);
294 dm_target_t* dm_target_autoload(const char *);
295 int dm_target_destroy(void);
296 int dm_target_insert(dm_target_t *);
297 prop_array_t dm_target_prop_list(void);
298 dm_target_t* dm_target_lookup(const char *);
299 int dm_target_rem(char *);
300 void dm_target_unbusy(dm_target_t *);
301 void dm_target_busy(dm_target_t *);
302 
303 /* XXX temporally add */
304 int dm_target_init(void);
305 
306 #define DM_MAX_PARAMS_SIZE 1024
307 
308 /* dm_target_linear.c */
309 int dm_target_linear_init(dm_dev_t *, void**, char *);
310 char * dm_target_linear_status(void *);
311 int dm_target_linear_strategy(dm_table_entry_t *, struct buf *);
312 int dm_target_linear_sync(dm_table_entry_t *);
313 int dm_target_linear_deps(dm_table_entry_t *, prop_array_t);
314 int dm_target_linear_destroy(dm_table_entry_t *);
315 int dm_target_linear_upcall(dm_table_entry_t *, struct buf *);
316 int dm_target_linear_secsize(dm_table_entry_t *, unsigned *);
317 
318 /* Generic function used to convert char to string */
319 uint64_t atoi(const char *);
320 
321 /* dm_target_stripe.c */
322 int dm_target_stripe_init(dm_dev_t *, void**, char *);
323 char * dm_target_stripe_status(void *);
324 int dm_target_stripe_strategy(dm_table_entry_t *, struct buf *);
325 int dm_target_stripe_sync(dm_table_entry_t *);
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 int dm_target_stripe_secsize(dm_table_entry_t *, unsigned *);
330 
331 /* dm_table.c  */
332 #define DM_TABLE_ACTIVE 0
333 #define DM_TABLE_INACTIVE 1
334 
335 int dm_table_destroy(dm_table_head_t *, uint8_t);
336 uint64_t dm_table_size(dm_table_head_t *);
337 uint64_t dm_inactive_table_size(dm_table_head_t *);
338 void dm_table_disksize(dm_table_head_t *, uint64_t *, unsigned *);
339 dm_table_t * dm_table_get_entry(dm_table_head_t *, uint8_t);
340 int dm_table_get_target_count(dm_table_head_t *, uint8_t);
341 void dm_table_release(dm_table_head_t *, uint8_t s);
342 void dm_table_switch_tables(dm_table_head_t *);
343 void dm_table_head_init(dm_table_head_t *);
344 void dm_table_head_destroy(dm_table_head_t *);
345 
346 /* dm_dev.c */
347 dm_dev_t* dm_dev_alloc(void);
348 void dm_dev_busy(dm_dev_t *);
349 int dm_dev_destroy(void);
350 dm_dev_t* dm_dev_detach(device_t);
351 int dm_dev_free(dm_dev_t *);
352 int dm_dev_init(void);
353 int dm_dev_insert(dm_dev_t *);
354 dm_dev_t* dm_dev_lookup(const char *, const char *, int);
355 prop_array_t dm_dev_prop_list(void);
356 dm_dev_t* dm_dev_rem(const char *, const char *, int);
357 /*int dm_dev_test_minor(int);*/
358 void dm_dev_unbusy(dm_dev_t *);
359 
360 /* dm_pdev.c */
361 int dm_pdev_decr(dm_pdev_t *);
362 int dm_pdev_destroy(void);
363 int dm_pdev_init(void);
364 dm_pdev_t* dm_pdev_insert(const char *);
365 
366 #endif /*_KERNEL*/
367 
368 #endif /*_DM_DEV_H_*/
369