sys/dev/disk/dm/device-mapper.c

   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");