xref: /dflybsd-src/sys/dev/disk/dm/dm_dev.c (revision a9656fbcd49c376aba5e04370d8b0f1fa96e063c)
1 /*        $NetBSD: dm_dev.c,v 1.8 2010/01/04 00:19:08 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 #include <sys/types.h>
33 #include <sys/param.h>
34 
35 #include <sys/disk.h>
36 #include <sys/disklabel.h>
37 #include <sys/ioccom.h>
38 #include <sys/malloc.h>
39 
40 #include "netbsd-dm.h"
41 #include "dm.h"
42 
43 static dm_dev_t *dm_dev_lookup_name(const char *);
44 static dm_dev_t *dm_dev_lookup_uuid(const char *);
45 static dm_dev_t *dm_dev_lookup_minor(int);
46 
47 static struct dm_dev_head dm_dev_list =
48 TAILQ_HEAD_INITIALIZER(dm_dev_list);
49 
50 struct lock dm_dev_mutex;
51 
52 /* dm_dev_mutex must be holdby caller before using disable_dev. */
53 void
54 disable_dev(dm_dev_t * dmv)
55 {
56 	TAILQ_REMOVE(&dm_dev_list, dmv, next_devlist);
57 	lockmgr(&dmv->dev_mtx, LK_EXCLUSIVE);
58 	lockmgr(&dm_dev_mutex, LK_RELEASE);
59 	while (dmv->ref_cnt != 0)
60 		cv_wait(&dmv->dev_cv, &dmv->dev_mtx);
61 	lockmgr(&dmv->dev_mtx, LK_RELEASE);
62 }
63 /*
64  * Generic function used to lookup dm_dev_t. Calling with dm_dev_name
65  * and dm_dev_uuid NULL is allowed.
66  */
67 dm_dev_t *
68 dm_dev_lookup(const char *dm_dev_name, const char *dm_dev_uuid,
69     int dm_dev_minor)
70 {
71 	dm_dev_t *dmv;
72 
73 	dmv = NULL;
74 	lockmgr(&dm_dev_mutex, LK_EXCLUSIVE);
75 
76 	/* KKASSERT(dm_dev_name != NULL && dm_dev_uuid != NULL && dm_dev_minor
77 	 * > 0); */
78 	if (dm_dev_minor > 0)
79 		if ((dmv = dm_dev_lookup_minor(dm_dev_minor)) != NULL) {
80 			dm_dev_busy(dmv);
81 			lockmgr(&dm_dev_mutex, LK_RELEASE);
82 			return dmv;
83 		}
84 	if (dm_dev_name != NULL)
85 		if ((dmv = dm_dev_lookup_name(dm_dev_name)) != NULL) {
86 			dm_dev_busy(dmv);
87 			lockmgr(&dm_dev_mutex, LK_RELEASE);
88 			return dmv;
89 		}
90 	if (dm_dev_uuid != NULL)
91 		if ((dmv = dm_dev_lookup_uuid(dm_dev_uuid)) != NULL) {
92 			dm_dev_busy(dmv);
93 			lockmgr(&dm_dev_mutex, LK_RELEASE);
94 			return dmv;
95 		}
96 	lockmgr(&dm_dev_mutex, LK_RELEASE);
97 	return NULL;
98 }
99 
100 
101 /*
102  * Lookup device with its minor number.
103  */
104 static dm_dev_t *
105 dm_dev_lookup_minor(int dm_dev_minor)
106 {
107 	dm_dev_t *dmv;
108 
109 	TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) {
110 		if (dm_dev_minor == dmv->minor)
111 			return dmv;
112 	}
113 
114 	return NULL;
115 }
116 /*
117  * Lookup device with it's device name.
118  */
119 static dm_dev_t *
120 dm_dev_lookup_name(const char *dm_dev_name)
121 {
122 	dm_dev_t *dmv;
123 	int dlen;
124 	int slen;
125 
126 	slen = strlen(dm_dev_name);
127 
128 	if (slen == 0)
129 		return NULL;
130 
131 	TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) {
132 
133 		dlen = strlen(dmv->name);
134 
135 		if (slen != dlen)
136 			continue;
137 
138 		if (strncmp(dm_dev_name, dmv->name, slen) == 0)
139 			return dmv;
140 	}
141 
142 	return NULL;
143 }
144 /*
145  * Lookup device with it's device uuid. Used mostly by LVM2tools.
146  */
147 static dm_dev_t *
148 dm_dev_lookup_uuid(const char *dm_dev_uuid)
149 {
150 	dm_dev_t *dmv;
151 	size_t len;
152 
153 	len = 0;
154 	len = strlen(dm_dev_uuid);
155 
156 	if (len == 0)
157 		return NULL;
158 
159 	TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) {
160 
161 		if (strlen(dmv->uuid) != len)
162 			continue;
163 
164 		if (strncmp(dm_dev_uuid, dmv->uuid, strlen(dmv->uuid)) == 0)
165 			return dmv;
166 	}
167 
168 	return NULL;
169 }
170 /*
171  * Insert new device to the global list of devices.
172  */
173 int
174 dm_dev_insert(dm_dev_t * dev)
175 {
176 	dm_dev_t *dmv;
177 	int r;
178 
179 	dmv = NULL;
180 	r = 0;
181 
182 	KKASSERT(dev != NULL);
183 	lockmgr(&dm_dev_mutex, LK_EXCLUSIVE);
184 	if (((dmv = dm_dev_lookup_uuid(dev->uuid)) == NULL) &&
185 	    ((dmv = dm_dev_lookup_name(dev->name)) == NULL) &&
186 	    ((dmv = dm_dev_lookup_minor(dev->minor)) == NULL)) {
187 
188 		TAILQ_INSERT_TAIL(&dm_dev_list, dev, next_devlist);
189 
190 	} else
191 		r = EEXIST;
192 
193 	lockmgr(&dm_dev_mutex, LK_RELEASE);
194 	return r;
195 }
196 #ifdef notyet
197 /*
198  * Lookup device with its minor number.
199  */
200 int
201 dm_dev_test_minor(int dm_dev_minor)
202 {
203 	dm_dev_t *dmv;
204 
205 	lockmgr(&dm_dev_mutex, LK_EXCLUSIVE);
206 	TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) {
207 		if (dm_dev_minor == dmv->minor) {
208 			lockmgr(&dm_dev_mutex, LK_RELEASE);
209 			return 1;
210 		}
211 	}
212 	lockmgr(&dm_dev_mutex, LK_RELEASE);
213 
214 	return 0;
215 }
216 #endif
217 
218 #if 0
219 /*
220  * dm_dev_lookup_devt look for selected device_t. We keep this routine
221  * outside of dm_dev_lookup because it is a temporally solution.
222  *
223  * TODO: This is a hack autoconf should be more flexible.
224  */
225 dm_dev_t *
226 dm_dev_detach(device_t devt)
227 {
228        dm_dev_t *dmv;
229 
230        lockmgr(&dm_dev_mutex, LK_EXCLUSIVE);
231        TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) {
232                if (devt == dmv->devt) {
233                        disable_dev(dmv);
234                        lockmgr(&dm_dev_mutex, LK_RELEASE);
235                        return dmv;
236                }
237        }
238        lockmgr(&dm_dev_mutex, LK_RELEASE);
239 
240        return NULL;
241 }
242 #endif
243 
244 /*
245  * Remove device selected with dm_dev from global list of devices.
246  */
247 dm_dev_t *
248 dm_dev_rem(const char *dm_dev_name, const char *dm_dev_uuid,
249     int dm_dev_minor)
250 {
251 	dm_dev_t *dmv;
252 	dmv = NULL;
253 
254 	lockmgr(&dm_dev_mutex, LK_EXCLUSIVE);
255 
256 	if (dm_dev_minor > 0)
257 		if ((dmv = dm_dev_lookup_minor(dm_dev_minor)) != NULL) {
258 			disable_dev(dmv);
259 			return dmv;
260 		}
261 	if (dm_dev_name != NULL)
262 		if ((dmv = dm_dev_lookup_name(dm_dev_name)) != NULL) {
263 			disable_dev(dmv);
264 			return dmv;
265 		}
266 	if (dm_dev_uuid != NULL)
267 		if ((dmv = dm_dev_lookup_name(dm_dev_uuid)) != NULL) {
268 			disable_dev(dmv);
269 			return dmv;
270 		}
271 	lockmgr(&dm_dev_mutex, LK_RELEASE);
272 
273 	return NULL;
274 }
275 /*
276  * Destroy all devices created in device-mapper. Remove all tables
277  * free all allocated memmory.
278  */
279 int
280 dm_dev_destroy(void)
281 {
282 	dm_dev_t *dmv;
283 	lockmgr(&dm_dev_mutex, LK_EXCLUSIVE);
284 
285 	while (TAILQ_FIRST(&dm_dev_list) != NULL) {
286 
287 		dmv = TAILQ_FIRST(&dm_dev_list);
288 
289 		TAILQ_REMOVE(&dm_dev_list, TAILQ_FIRST(&dm_dev_list),
290 		    next_devlist);
291 
292 		lockmgr(&dmv->dev_mtx, LK_EXCLUSIVE);
293 
294 		while (dmv->ref_cnt != 0)
295 			cv_wait(&dmv->dev_cv, &dmv->dev_mtx);
296 
297 		/* Destroy active table first.  */
298 		dm_table_destroy(&dmv->table_head, DM_TABLE_ACTIVE);
299 
300 		/* Destroy inactive table if exits, too. */
301 		dm_table_destroy(&dmv->table_head, DM_TABLE_INACTIVE);
302 
303 		dm_table_head_destroy(&dmv->table_head);
304 
305 		lockmgr(&dmv->dev_mtx, LK_RELEASE);
306 		lockuninit(&dmv->dev_mtx);
307 		cv_destroy(&dmv->dev_cv);
308 
309 		(void) kfree(dmv, M_DM);
310 	}
311 	lockmgr(&dm_dev_mutex, LK_RELEASE);
312 
313 	lockuninit(&dm_dev_mutex);
314 	return 0;
315 }
316 /*
317  * Allocate new device entry.
318  */
319 dm_dev_t *
320 dm_dev_alloc(void)
321 {
322 	dm_dev_t *dmv;
323 
324 	dmv = kmalloc(sizeof(dm_dev_t), M_DM, M_WAITOK | M_ZERO);
325 
326 	if (dmv != NULL)
327 		dmv->diskp = kmalloc(sizeof(struct disk), M_DM, M_WAITOK | M_ZERO);
328 
329 	return dmv;
330 }
331 /*
332  * Freed device entry.
333  */
334 int
335 dm_dev_free(dm_dev_t * dmv)
336 {
337 	KKASSERT(dmv != NULL);
338 
339 	lockuninit(&dmv->dev_mtx);
340 	lockuninit(&dmv->diskp_mtx);
341 	cv_destroy(&dmv->dev_cv);
342 
343 	if (dmv->diskp != NULL)
344 		(void) kfree(dmv->diskp, M_DM);
345 
346 	(void) kfree(dmv, M_DM);
347 
348 	return 0;
349 }
350 
351 void
352 dm_dev_busy(dm_dev_t * dmv)
353 {
354 	lockmgr(&dmv->dev_mtx, LK_EXCLUSIVE);
355 	dmv->ref_cnt++;
356 	lockmgr(&dmv->dev_mtx, LK_RELEASE);
357 }
358 
359 void
360 dm_dev_unbusy(dm_dev_t * dmv)
361 {
362 	KKASSERT(dmv->ref_cnt != 0);
363 
364 	lockmgr(&dmv->dev_mtx, LK_EXCLUSIVE);
365 	if (--dmv->ref_cnt == 0)
366 		cv_broadcast(&dmv->dev_cv);
367 	lockmgr(&dmv->dev_mtx, LK_RELEASE);
368 }
369 /*
370  * Return prop_array of dm_targer_list dictionaries.
371  */
372 prop_array_t
373 dm_dev_prop_list(void)
374 {
375 	dm_dev_t *dmv;
376 	prop_array_t dev_array;
377 	prop_dictionary_t dev_dict;
378 
379 	dev_array = prop_array_create();
380 
381 	lockmgr(&dm_dev_mutex, LK_EXCLUSIVE);
382 
383 	TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) {
384 		dev_dict = prop_dictionary_create();
385 
386 		prop_dictionary_set_cstring(dev_dict, DM_DEV_NAME, dmv->name);
387 		prop_dictionary_set_uint32(dev_dict, DM_DEV_DEV, dmv->minor);
388 
389 		prop_array_add(dev_array, dev_dict);
390 		prop_object_release(dev_dict);
391 	}
392 
393 	lockmgr(&dm_dev_mutex, LK_RELEASE);
394 	return dev_array;
395 }
396 /*
397  * Initialize global device mutex.
398  */
399 int
400 dm_dev_init(void)
401 {
402 	TAILQ_INIT(&dm_dev_list);	/* initialize global dev list */
403 	lockinit(&dm_dev_mutex, "dmdevlist", 0, LK_CANRECURSE);
404 	return 0;
405 }
406