1 /* $NetBSD: device-mapper.c,v 1.22 2010/03/26 15:46:04 jakllsch Exp $ */ 2 3 /* 4 * Copyright (c) 2010-2011 Alex Hornung <alex@alexhornung.com> 5 * Copyright (c) 2010 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Adam Hamsik. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * I want to say thank you to all people who helped me with this project. 35 */ 36 37 #include <sys/ctype.h> 38 #include <sys/conf.h> 39 #include <sys/device.h> 40 #include <sys/disk.h> 41 #include <sys/disklabel.h> 42 #include <sys/dtype.h> 43 #include <sys/malloc.h> 44 #include <sys/module.h> 45 #include <sys/sysctl.h> 46 #include <dev/disk/dm/dm.h> 47 #include <dev/disk/dm/netbsd-dm.h> 48 49 static d_ioctl_t dmioctl; 50 static d_open_t dmopen; 51 static d_close_t dmclose; 52 static d_psize_t dmsize; 53 static d_strategy_t dmstrategy; 54 static d_dump_t dmdump; 55 56 /* New module handle and destroy routines */ 57 static int dm_modcmd(module_t mod, int cmd, void *unused); 58 static int dmdestroy(void); 59 60 static void dm_doinit(void); 61 62 static int dm_cmd_to_fun(prop_dictionary_t); 63 static int disk_ioctl_switch(cdev_t, u_long, void *); 64 65 static struct dev_ops dmctl_ops = { 66 { "dm", 0, D_MPSAFE }, 67 .d_open = dmopen, 68 .d_close = dmclose, 69 .d_ioctl = dmioctl, 70 }; 71 72 struct dev_ops dm_ops = { 73 { "dm", 0, D_DISK | D_MPSAFE }, 74 .d_open = dmopen, 75 .d_close = dmclose, 76 .d_read = physread, 77 .d_write = physwrite, 78 .d_ioctl = dmioctl, 79 .d_strategy = dmstrategy, 80 .d_psize = dmsize, 81 .d_dump = dmdump, 82 }; 83 84 MALLOC_DEFINE(M_DM, "dm", "Device Mapper allocations"); 85 86 int dm_debug_level = 0; 87 88 extern uint64_t dm_dev_counter; 89 90 static cdev_t dmcdev; 91 92 static moduledata_t dm_mod = { 93 "dm", 94 dm_modcmd, 95 NULL 96 }; 97 DECLARE_MODULE(dm, dm_mod, SI_SUB_RAID, SI_ORDER_ANY); 98 MODULE_VERSION(dm, 1); 99 100 /* 101 * This structure is used to translate command sent to kernel driver in 102 * <key>command</key> 103 * <value></value> 104 * to function 105 */ 106 /* 107 * This array is used to translate cmd to function pointer. 108 * 109 * Interface between libdevmapper and lvm2tools uses different 110 * names for one IOCTL call because libdevmapper do another thing 111 * then. When I run "info" or "mknodes" libdevmapper will send same 112 * ioctl to kernel but will do another things in userspace. 113 */ 114 static struct cmd_function { 115 const char *cmd; 116 int (*fn)(prop_dictionary_t); 117 } cmd_fn[] = { 118 {.cmd = "version", .fn = NULL}, 119 {.cmd = "targets", .fn = dm_list_versions_ioctl}, 120 {.cmd = "create", .fn = dm_dev_create_ioctl}, 121 {.cmd = "info", .fn = dm_dev_status_ioctl}, 122 {.cmd = "mknodes", .fn = dm_dev_status_ioctl}, 123 {.cmd = "names", .fn = dm_dev_list_ioctl}, 124 {.cmd = "suspend", .fn = dm_dev_suspend_ioctl}, 125 {.cmd = "remove", .fn = dm_dev_remove_ioctl}, 126 {.cmd = "remove_all", .fn = dm_dev_remove_all_ioctl}, 127 {.cmd = "rename", .fn = dm_dev_rename_ioctl}, 128 {.cmd = "resume", .fn = dm_dev_resume_ioctl}, 129 {.cmd = "clear", .fn = dm_table_clear_ioctl}, 130 {.cmd = "deps", .fn = dm_table_deps_ioctl}, 131 {.cmd = "reload", .fn = dm_table_load_ioctl}, 132 {.cmd = "status", .fn = dm_table_status_ioctl}, 133 {.cmd = "table", .fn = dm_table_status_ioctl}, 134 {.cmd = "message", .fn = dm_message_ioctl}, 135 }; 136 137 /* 138 * New module handle routine 139 */ 140 static int 141 dm_modcmd(module_t mod, int cmd, void *unused) 142 { 143 int error; 144 145 error = 0; 146 147 switch (cmd) { 148 case MOD_LOAD: 149 dm_doinit(); 150 kprintf("Device Mapper version %d.%d.%d loaded\n", 151 DM_VERSION_MAJOR, DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL); 152 break; 153 154 case MOD_UNLOAD: 155 /* 156 * Disable unloading of dm module if there are any devices 157 * defined in driver. This is probably too strong we need 158 * to disable auto-unload only if there is mounted dm device 159 * present. 160 */ 161 if (dm_dev_counter > 0) 162 return EBUSY; 163 /* race window here */ 164 165 error = dmdestroy(); 166 if (error) 167 break; 168 kprintf("Device Mapper unloaded\n"); 169 break; 170 } 171 172 return error; 173 } 174 175 static void 176 dm_doinit(void) 177 { 178 dm_target_init(); 179 dm_dev_init(); 180 dm_pdev_init(); 181 dmcdev = make_dev(&dmctl_ops, 0, UID_ROOT, GID_OPERATOR, 0640, "mapper/control"); 182 } 183 184 /* 185 * Destroy routine 186 */ 187 static int 188 dmdestroy(void) 189 { 190 destroy_dev(dmcdev); 191 192 dm_dev_uninit(); 193 dm_pdev_uninit(); 194 dm_target_uninit(); 195 196 return 0; 197 } 198 199 static int 200 dmopen(struct dev_open_args *ap) 201 { 202 cdev_t dev = ap->a_head.a_dev; 203 dm_dev_t *dmv; 204 205 /* Shortcut for the control device */ 206 if (minor(dev) == 0) 207 return 0; 208 209 if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL) 210 return ENXIO; 211 212 dmv->is_open = 1; 213 dm_dev_unbusy(dmv); 214 215 dmdebug("minor=%" PRIu32 "\n", minor(ap->a_head.a_dev)); 216 return 0; 217 } 218 219 static int 220 dmclose(struct dev_close_args *ap) 221 { 222 cdev_t dev = ap->a_head.a_dev; 223 dm_dev_t *dmv; 224 225 /* Shortcut for the control device */ 226 if (minor(dev) == 0) 227 return 0; 228 229 if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL) 230 return ENXIO; 231 232 dmv->is_open = 0; 233 dm_dev_unbusy(dmv); 234 235 dmdebug("minor=%" PRIu32 "\n", minor(ap->a_head.a_dev)); 236 return 0; 237 } 238 239 240 static int 241 dmioctl(struct dev_ioctl_args *ap) 242 { 243 cdev_t dev = ap->a_head.a_dev; 244 u_long cmd = ap->a_cmd; 245 void *data = ap->a_data; 246 struct plistref *pref; 247 248 int r, err; 249 prop_dictionary_t dm_dict_in; 250 251 err = r = 0; 252 KKASSERT(data != NULL); 253 254 if ((r = disk_ioctl_switch(dev, cmd, data)) != ENOTTY) 255 return r; /* Handled disk ioctl */ 256 257 switch(cmd) { 258 case NETBSD_DM_IOCTL: 259 dmdebug("NETBSD_DM_IOCTL called\n"); 260 break; 261 default: 262 dmdebug("Unknown ioctl %lu called\n", cmd); 263 return ENOTTY; 264 } 265 266 pref = (struct plistref *)data; /* data is for libprop */ 267 if ((r = prop_dictionary_copyin_ioctl(pref, cmd, &dm_dict_in)) != 0) 268 return r; 269 270 if ((r = dm_check_version(dm_dict_in)) == 0) 271 err = dm_cmd_to_fun(dm_dict_in); 272 273 r = prop_dictionary_copyout_ioctl(pref, cmd, dm_dict_in); 274 prop_object_release(dm_dict_in); 275 276 /* Return the dm ioctl error if any. */ 277 if (err) 278 return err; 279 return r; 280 } 281 282 /* 283 * Translate command sent from libdevmapper to func. 284 */ 285 static int 286 dm_cmd_to_fun(prop_dictionary_t dm_dict) 287 { 288 int i, size; 289 prop_string_t command; 290 struct cmd_function *p = NULL; 291 292 size = sizeof(cmd_fn) / sizeof(cmd_fn[0]); 293 294 if ((command = prop_dictionary_get(dm_dict, DM_IOCTL_COMMAND)) == NULL) 295 return EINVAL; 296 297 for (i = 0; i < size; i++) { 298 p = &cmd_fn[i]; 299 if (prop_string_equals_cstring(command, p->cmd)) 300 break; 301 } 302 303 KKASSERT(p); 304 if (i == size) { 305 dmdebug("Unknown ioctl\n"); 306 return EINVAL; 307 } 308 309 dmdebug("ioctl %s called %p\n", p->cmd, p->fn); 310 if (p->fn == NULL) 311 return 0; /* No handler required */ 312 313 return p->fn(dm_dict); 314 } 315 316 /* 317 * Check for disk specific ioctls. 318 */ 319 static int 320 disk_ioctl_switch(cdev_t dev, u_long cmd, void *data) 321 { 322 dm_dev_t *dmv; 323 324 /* disk ioctls make sense only on block devices */ 325 if (minor(dev) == 0) 326 return ENOTTY; 327 328 switch(cmd) { 329 case DIOCGPART: 330 if ((dmv = dev->si_drv1) == NULL) 331 return ENODEV; 332 if (dmv->diskp->d_info.d_media_blksize == 0) { 333 return ENOTSUP; 334 } else { 335 u_int64_t size; 336 struct partinfo *dpart = data; 337 bzero(dpart, sizeof(*dpart)); 338 339 size = dm_table_size(&dmv->table_head); 340 dpart->media_offset = 0; 341 dpart->media_size = size * DEV_BSIZE; 342 dpart->media_blocks = size; 343 dpart->media_blksize = DEV_BSIZE; 344 dpart->fstype = FS_BSDFFS; 345 } 346 dmdebug("DIOCGPART called\n"); 347 break; 348 349 default: 350 dmdebug("Unknown disk ioctl %lu called\n", cmd); 351 return ENOTTY; 352 break; /* NOT REACHED */ 353 } 354 355 return 0; 356 } 357 358 /* 359 * Do all IO operations on dm logical devices. 360 */ 361 static int 362 dmstrategy(struct dev_strategy_args *ap) 363 { 364 cdev_t dev = ap->a_head.a_dev; 365 dm_dev_t *dmv = dev->si_drv1; 366 dm_table_t *tbl; 367 dm_table_entry_t *table_en; 368 369 struct bio *bio = ap->a_bio; 370 struct buf *bp = bio->bio_buf; 371 struct buf *nestbuf; 372 373 uint64_t buf_start, buf_len, issued_len; 374 uint64_t table_start, table_end; 375 uint64_t start, end; 376 int bypass; 377 378 buf_start = bio->bio_offset; 379 buf_len = bp->b_bcount; 380 issued_len = 0; 381 382 switch(bp->b_cmd) { 383 case BUF_CMD_READ: 384 case BUF_CMD_WRITE: 385 case BUF_CMD_FREEBLKS: 386 bypass = 0; 387 break; 388 case BUF_CMD_FLUSH: 389 bypass = 1; 390 KKASSERT(buf_len == 0); 391 break; 392 default: 393 bp->b_error = EIO; 394 bp->b_resid = bp->b_bcount; 395 biodone(bio); 396 return 0; 397 } 398 399 if (bypass == 0 && 400 bounds_check_with_mediasize(bio, DEV_BSIZE, 401 dm_table_size(&dmv->table_head)) <= 0) { 402 bp->b_resid = bp->b_bcount; 403 biodone(bio); 404 return 0; 405 } 406 407 /* Select active table */ 408 tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE); 409 410 nestiobuf_init(bio); 411 devstat_start_transaction(&dmv->stats); 412 413 /* 414 * Find out what tables I want to select. 415 */ 416 TAILQ_FOREACH(table_en, tbl, next) { 417 /* 418 * I need need number of bytes not blocks. 419 */ 420 table_start = table_en->start * DEV_BSIZE; 421 table_end = table_start + table_en->length * DEV_BSIZE; 422 423 /* 424 * Calculate the start and end 425 */ 426 start = MAX(table_start, buf_start); 427 end = MIN(table_end, buf_start + buf_len); 428 429 if (dm_debug_level) { 430 kprintf("----------------------------------------\n"); 431 kprintf("table_start %010" PRIu64", table_end %010" 432 PRIu64 "\n", table_start, table_end); 433 kprintf("buf_start %010" PRIu64", buf_len %010" 434 PRIu64"\n", buf_start, buf_len); 435 kprintf("start-buf_start %010"PRIu64", end %010" 436 PRIu64"\n", start - buf_start, end); 437 kprintf("start %010" PRIu64", end %010" 438 PRIu64"\n", start, end); 439 } 440 441 if (bypass) { 442 nestbuf = getpbuf(NULL); 443 nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS; 444 445 nestiobuf_add(bio, nestbuf, 0, 0, &dmv->stats); 446 nestbuf->b_bio1.bio_offset = 0; 447 table_en->target->strategy(table_en, nestbuf); 448 } else if (start < end) { 449 nestbuf = getpbuf(NULL); 450 nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS; 451 452 nestiobuf_add(bio, nestbuf, 453 start - buf_start, end - start, 454 &dmv->stats); 455 issued_len += end - start; 456 457 nestbuf->b_bio1.bio_offset = start - table_start; 458 table_en->target->strategy(table_en, nestbuf); 459 } 460 } 461 462 if (issued_len < buf_len) 463 nestiobuf_error(bio, EINVAL); 464 nestiobuf_start(bio); 465 dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE); 466 467 return 0; 468 } 469 470 static int 471 dmdump(struct dev_dump_args *ap) 472 { 473 cdev_t dev = ap->a_head.a_dev; 474 dm_dev_t *dmv = dev->si_drv1; 475 dm_table_t *tbl; 476 dm_table_entry_t *table_en; 477 478 uint64_t buf_start, buf_len, issued_len; 479 uint64_t table_start, table_end; 480 uint64_t start, end; 481 int error = 0; 482 483 buf_start = ap->a_offset; 484 buf_len = ap->a_length; 485 issued_len = 0; 486 487 /* Select active table */ 488 tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE); 489 490 /* 491 * Find out what tables I want to select. 492 */ 493 TAILQ_FOREACH(table_en, tbl, next) { 494 /* 495 * I need need number of bytes not blocks. 496 */ 497 table_start = table_en->start * DEV_BSIZE; 498 table_end = table_start + table_en->length * DEV_BSIZE; 499 500 /* 501 * Calculate the start and end 502 */ 503 start = MAX(table_start, buf_start); 504 end = MIN(table_end, buf_start + buf_len); 505 506 if (ap->a_length == 0) { 507 if (table_en->target->dump == NULL) { 508 error = ENXIO; 509 goto out; 510 } 511 512 table_en->target->dump(table_en, NULL, 0, 0); 513 } else if (start < end) { 514 if (table_en->target->dump == NULL) { 515 error = ENXIO; 516 goto out; 517 } 518 519 table_en->target->dump(table_en, 520 (char *)ap->a_virtual + start - buf_start, 521 end - start, start - table_start); 522 523 issued_len += end - start; 524 } 525 } 526 527 if (issued_len < buf_len) 528 error = EINVAL; 529 530 out: 531 dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE); 532 533 return error; 534 } 535 536 static int 537 dmsize(struct dev_psize_args *ap) 538 { 539 cdev_t dev = ap->a_head.a_dev; 540 dm_dev_t *dmv; 541 542 if ((dmv = dev->si_drv1) == NULL) 543 return ENXIO; 544 545 ap->a_result = (int64_t)dm_table_size(&dmv->table_head); 546 547 return 0; 548 } 549 550 void 551 dmsetdiskinfo(struct disk *disk, dm_table_head_t *head) 552 { 553 struct disk_info info; 554 uint64_t dmp_size; 555 556 dmp_size = dm_table_size(head); 557 558 bzero(&info, sizeof(struct disk_info)); 559 info.d_media_blksize = DEV_BSIZE; 560 info.d_media_blocks = dmp_size; 561 #if 0 562 /* this is set by disk_setdiskinfo */ 563 info.d_media_size = dmp_size * DEV_BSIZE; 564 #endif 565 info.d_dsflags = DSO_MBRQUIET | DSO_DEVICEMAPPER | DSO_RAWPSIZE; 566 567 info.d_secpertrack = 32; 568 info.d_nheads = 64; 569 info.d_secpercyl = info.d_secpertrack * info.d_nheads; 570 info.d_ncylinders = dmp_size / info.d_secpercyl; 571 572 /* 573 * The probe is asynchronous so call disk_config() to 574 * wait for it to complete. 575 */ 576 disk_setdiskinfo(disk, &info); 577 disk_config(NULL); 578 } 579 580 /* 581 * Transform char s to uint64_t offset number. 582 */ 583 uint64_t 584 atoi64(const char *s) 585 { 586 uint64_t n; 587 n = 0; 588 589 while (*s != '\0') { 590 if (!isdigit(*s)) 591 break; 592 593 n = (10 * n) + (*s - '0'); 594 s++; 595 } 596 597 return n; 598 } 599 600 char * 601 dm_alloc_string(int len) 602 { 603 if (len <= 0) 604 len = DM_MAX_PARAMS_SIZE; 605 return kmalloc(len, M_DM, M_WAITOK | M_ZERO); 606 } 607 608 void 609 dm_builtin_init(void *arg) 610 { 611 modeventhand_t evh = (modeventhand_t)arg; 612 613 KKASSERT(evh != NULL); 614 evh(NULL, MOD_LOAD, NULL); 615 } 616 617 void 618 dm_builtin_uninit(void *arg) 619 { 620 modeventhand_t evh = (modeventhand_t)arg; 621 622 KKASSERT(evh != NULL); 623 evh(NULL, MOD_UNLOAD, NULL); 624 } 625 626 TUNABLE_INT("debug.dm_debug", &dm_debug_level); 627 SYSCTL_INT(_debug, OID_AUTO, dm_debug, CTLFLAG_RW, &dm_debug_level, 628 0, "Enable device mapper debugging"); 629