1 /* $NetBSD: dm_dev.c,v 1.18 2020/07/08 15:07:13 thorpej 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 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: dm_dev.c,v 1.18 2020/07/08 15:07:13 thorpej Exp $"); 33 34 #include <sys/types.h> 35 #include <sys/param.h> 36 #include <sys/disk.h> 37 #include <sys/disklabel.h> 38 #include <sys/ioctl.h> 39 #include <sys/ioccom.h> 40 #include <sys/kmem.h> 41 42 #include "netbsd-dm.h" 43 #include "dm.h" 44 45 static dm_dev_t *dm_dev_lookup_name(const char *); 46 static dm_dev_t *dm_dev_lookup_uuid(const char *); 47 static dm_dev_t *dm_dev_lookup_minor(int); 48 49 static struct dm_dev_head dm_dev_list = TAILQ_HEAD_INITIALIZER(dm_dev_list); 50 51 static kmutex_t dm_dev_mutex; 52 53 /* dm_dev_mutex must be holdby caller before using disable_dev. */ 54 static void 55 disable_dev(dm_dev_t *dmv) 56 { 57 58 TAILQ_REMOVE(&dm_dev_list, dmv, next_devlist); 59 mutex_enter(&dmv->dev_mtx); 60 mutex_exit(&dm_dev_mutex); 61 while (dmv->ref_cnt != 0) 62 cv_wait(&dmv->dev_cv, &dmv->dev_mtx); 63 mutex_exit(&dmv->dev_mtx); 64 } 65 66 /* 67 * Generic function used to lookup dm_dev_t. Calling with dm_dev_name 68 * and dm_dev_uuid NULL is allowed. 69 */ 70 dm_dev_t * 71 dm_dev_lookup(const char *dm_dev_name, const char *dm_dev_uuid, 72 int dm_dev_minor) 73 { 74 dm_dev_t *dmv; 75 76 mutex_enter(&dm_dev_mutex); 77 /* KASSERT(dm_dev_name != NULL && dm_dev_uuid != NULL && dm_dev_minor 78 * > 0); */ 79 if (dm_dev_minor > 0) 80 if ((dmv = dm_dev_lookup_minor(dm_dev_minor)) != NULL) { 81 dm_dev_busy(dmv); 82 mutex_exit(&dm_dev_mutex); 83 return dmv; 84 } 85 if (dm_dev_name != NULL) 86 if ((dmv = dm_dev_lookup_name(dm_dev_name)) != NULL) { 87 dm_dev_busy(dmv); 88 mutex_exit(&dm_dev_mutex); 89 return dmv; 90 } 91 if (dm_dev_uuid != NULL) 92 if ((dmv = dm_dev_lookup_uuid(dm_dev_uuid)) != NULL) { 93 dm_dev_busy(dmv); 94 mutex_exit(&dm_dev_mutex); 95 return dmv; 96 } 97 mutex_exit(&dm_dev_mutex); 98 99 return NULL; 100 } 101 102 /* 103 * Lookup device with its minor number. 104 */ 105 static dm_dev_t * 106 dm_dev_lookup_minor(int dm_dev_minor) 107 { 108 dm_dev_t *dmv; 109 110 TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) 111 if (dm_dev_minor == dmv->minor) 112 return dmv; 113 114 return NULL; 115 } 116 117 /* 118 * Lookup device with its device name. 119 */ 120 static dm_dev_t * 121 dm_dev_lookup_name(const char *dm_dev_name) 122 { 123 dm_dev_t *dmv; 124 size_t dlen; 125 size_t slen; 126 127 slen = strlen(dm_dev_name); 128 129 if (slen == 0) 130 return NULL; 131 132 TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) { 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 /* 146 * Lookup device with its device uuid. Used mostly by LVM2tools. 147 */ 148 static dm_dev_t * 149 dm_dev_lookup_uuid(const char *dm_dev_uuid) 150 { 151 dm_dev_t *dmv; 152 size_t len; 153 154 len = 0; 155 len = strlen(dm_dev_uuid); 156 157 if (len == 0) 158 return NULL; 159 160 TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) { 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 /* 172 * Insert new device to the global list of devices. 173 */ 174 int 175 dm_dev_insert(dm_dev_t *dev) 176 { 177 dm_dev_t *dmv; 178 int r; 179 180 dmv = NULL; 181 r = 0; 182 183 KASSERT(dev != NULL); 184 mutex_enter(&dm_dev_mutex); 185 if (((dmv = dm_dev_lookup_uuid(dev->uuid)) == NULL) && 186 ((dmv = dm_dev_lookup_name(dev->name)) == NULL) && 187 ((dmv = dm_dev_lookup_minor(dev->minor)) == NULL)) { 188 TAILQ_INSERT_TAIL(&dm_dev_list, dev, next_devlist); 189 } else 190 r = EEXIST; 191 mutex_exit(&dm_dev_mutex); 192 193 return r; 194 } 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 mutex_enter(&dm_dev_mutex); 206 TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) { 207 if (dm_dev_minor == dmv->minor) { 208 mutex_exit(&dm_dev_mutex); 209 return 1; 210 } 211 } 212 mutex_exit(&dm_dev_mutex); 213 214 return 0; 215 } 216 #endif 217 218 /* 219 * dm_dev_lookup_devt look for selected device_t. We keep this routine 220 * outside of dm_dev_lookup because it is a temporally solution. 221 * 222 * TODO: This is a hack autoconf should be more flexible. 223 */ 224 dm_dev_t * 225 dm_dev_detach(device_t devt) 226 { 227 dm_dev_t *dmv; 228 229 mutex_enter(&dm_dev_mutex); 230 TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) { 231 if (devt == dmv->devt) { 232 disable_dev(dmv); 233 return dmv; 234 } 235 } 236 mutex_exit(&dm_dev_mutex); 237 238 return NULL; 239 } 240 241 /* 242 * Remove device selected with dm_dev from global list of devices. 243 */ 244 dm_dev_t * 245 dm_dev_rem(const char *dm_dev_name, const char *dm_dev_uuid, 246 int dm_dev_minor) 247 { 248 dm_dev_t *dmv; 249 250 mutex_enter(&dm_dev_mutex); 251 if (dm_dev_minor > 0) 252 if ((dmv = dm_dev_lookup_minor(dm_dev_minor)) != NULL) { 253 disable_dev(dmv); 254 return dmv; 255 } 256 if (dm_dev_name != NULL) 257 if ((dmv = dm_dev_lookup_name(dm_dev_name)) != NULL) { 258 disable_dev(dmv); 259 return dmv; 260 } 261 if (dm_dev_uuid != NULL) 262 if ((dmv = dm_dev_lookup_name(dm_dev_uuid)) != NULL) { 263 disable_dev(dmv); 264 return dmv; 265 } 266 mutex_exit(&dm_dev_mutex); 267 268 return NULL; 269 } 270 271 /* 272 * Destroy all devices created in device-mapper. Remove all tables 273 * free all allocated memmory. 274 */ 275 int 276 dm_dev_destroy(void) 277 { 278 dm_dev_t *dmv; 279 280 mutex_enter(&dm_dev_mutex); 281 while (TAILQ_FIRST(&dm_dev_list) != NULL) { 282 dmv = TAILQ_FIRST(&dm_dev_list); 283 284 TAILQ_REMOVE(&dm_dev_list, TAILQ_FIRST(&dm_dev_list), 285 next_devlist); 286 287 mutex_enter(&dmv->dev_mtx); 288 289 while (dmv->ref_cnt != 0) 290 cv_wait(&dmv->dev_cv, &dmv->dev_mtx); 291 292 /* Destroy active table first. */ 293 dm_table_destroy(&dmv->table_head, DM_TABLE_ACTIVE); 294 295 /* Destroy inactive table if exits, too. */ 296 dm_table_destroy(&dmv->table_head, DM_TABLE_INACTIVE); 297 298 dm_table_head_destroy(&dmv->table_head); 299 300 mutex_exit(&dmv->dev_mtx); 301 mutex_destroy(&dmv->dev_mtx); 302 cv_destroy(&dmv->dev_cv); 303 304 kmem_free(dmv, sizeof(dm_dev_t)); 305 } 306 mutex_exit(&dm_dev_mutex); 307 308 mutex_destroy(&dm_dev_mutex); 309 return 0; 310 } 311 312 /* 313 * Allocate new device entry. 314 */ 315 dm_dev_t * 316 dm_dev_alloc(void) 317 { 318 dm_dev_t *dmv; 319 320 dmv = kmem_zalloc(sizeof(dm_dev_t), KM_SLEEP); 321 dmv->diskp = kmem_zalloc(sizeof(struct disk), KM_SLEEP); 322 return dmv; 323 } 324 325 /* 326 * Freed device entry. 327 */ 328 int 329 dm_dev_free(dm_dev_t *dmv) 330 { 331 332 KASSERT(dmv != NULL); 333 334 mutex_destroy(&dmv->dev_mtx); 335 mutex_destroy(&dmv->diskp_mtx); 336 cv_destroy(&dmv->dev_cv); 337 338 if (dmv->diskp != NULL) 339 kmem_free(dmv->diskp, sizeof(struct disk)); 340 341 kmem_free(dmv, sizeof(dm_dev_t)); 342 343 return 0; 344 } 345 346 void 347 dm_dev_busy(dm_dev_t *dmv) 348 { 349 350 mutex_enter(&dmv->dev_mtx); 351 dmv->ref_cnt++; 352 mutex_exit(&dmv->dev_mtx); 353 } 354 355 void 356 dm_dev_unbusy(dm_dev_t *dmv) 357 { 358 359 KASSERT(dmv->ref_cnt != 0); 360 361 mutex_enter(&dmv->dev_mtx); 362 if (--dmv->ref_cnt == 0) 363 cv_broadcast(&dmv->dev_cv); 364 mutex_exit(&dmv->dev_mtx); 365 } 366 367 /* 368 * Return prop_array of dm_targer_list dictionaries. 369 */ 370 prop_array_t 371 dm_dev_prop_list(void) 372 { 373 dm_dev_t *dmv; 374 prop_array_t dev_array; 375 prop_dictionary_t dev_dict; 376 377 dev_array = prop_array_create(); 378 379 mutex_enter(&dm_dev_mutex); 380 381 TAILQ_FOREACH(dmv, &dm_dev_list, next_devlist) { 382 dev_dict = prop_dictionary_create(); 383 384 prop_dictionary_set_string(dev_dict, DM_DEV_NAME, dmv->name); 385 prop_dictionary_set_uint32(dev_dict, DM_DEV_DEV, dmv->minor); 386 387 prop_array_add(dev_array, dev_dict); 388 prop_object_release(dev_dict); 389 } 390 391 mutex_exit(&dm_dev_mutex); 392 return dev_array; 393 } 394 395 /* 396 * Initialize global device mutex. 397 */ 398 int 399 dm_dev_init(void) 400 { 401 402 TAILQ_INIT(&dm_dev_list); /* initialize global dev list */ 403 mutex_init(&dm_dev_mutex, MUTEX_DEFAULT, IPL_NONE); 404 return 0; 405 } 406