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 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 /*
  33  * I want to say thank you to all people who helped me with this project.
  34  */
  35
  36 #include <sys/types.h>
  37 #include <sys/param.h>
  38
  39 #include <sys/buf.h>
  40 #include <sys/conf.h>
  41 #include <sys/device.h>
  42 #include <sys/devfs.h>
  43 #include <sys/disk.h>
  44 #include <sys/disklabel.h>
  45 #include <sys/dtype.h>
  46 #include <sys/ioccom.h>
  47 #include <sys/malloc.h>
  48 #include <sys/module.h>
  49 #include <sys/sysctl.h>
  50
  51 #include "netbsd-dm.h"
  52 #include "dm.h"
  53
  54 static  d_ioctl_t       dmioctl;
  55 static  d_open_t        dmopen;
  56 static  d_close_t       dmclose;
  57 static  d_psize_t       dmsize;
  58 static  d_strategy_t    dmstrategy;
  59 static  d_dump_t        dmdump;
  60
  61 /* attach and detach routines */
  62 void dmattach(int);
  63 static int dm_modcmd(module_t mod, int cmd, void *unused);
  64 static int dmdestroy(void);
  65
  66 static void dm_doinit(void);
  67
  68 static int dm_cmd_to_fun(prop_dictionary_t);
  69 static int disk_ioctl_switch(cdev_t, u_long, void *);
  70 static int dm_ioctl_switch(u_long);
  71 #if 0
  72 static void dmminphys(struct buf *);
  73 #endif
  74
  75 struct devfs_bitmap dm_minor_bitmap;
  76
  77 /* ***Variable-definitions*** */
  78 struct dev_ops dm_ops = {
  79         { "dm", 0, D_DISK | D_MPSAFE },
  80         .d_open         = dmopen,
  81         .d_close        = dmclose,
  82         .d_read         = physread,
  83         .d_write        = physwrite,
  84         .d_ioctl        = dmioctl,
  85         .d_strategy     = dmstrategy,
  86         .d_psize        = dmsize,
  87         .d_dump         = dmdump,
  88 /* D_DISK */
  89 };
  90
  91 MALLOC_DEFINE(M_DM, "dm", "Device Mapper allocations");
  92
  93 int dm_debug_level = 0;
  94
  95 extern uint64_t dm_dev_counter;
  96
  97 static cdev_t dmcdev;
  98
  99 static moduledata_t dm_mod = {
 100     "dm",
 101     dm_modcmd,
 102     NULL
 103 };
 104 DECLARE_MODULE(dm, dm_mod, SI_SUB_RAID, SI_ORDER_ANY);
 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  */
 115 static struct cmd_function cmd_fn[] = {
 116                 { .cmd = "version", .fn = dm_get_version_ioctl},
 117                 { .cmd = "targets", .fn = dm_list_versions_ioctl},
 118                 { .cmd = "create",  .fn = dm_dev_create_ioctl},
 119                 { .cmd = "info",    .fn = dm_dev_status_ioctl},
 120                 { .cmd = "mknodes", .fn = dm_dev_status_ioctl},
 121                 { .cmd = "names",   .fn = dm_dev_list_ioctl},
 122                 { .cmd = "suspend", .fn = dm_dev_suspend_ioctl},
 123                 { .cmd = "remove",  .fn = dm_dev_remove_ioctl},
 124                 { .cmd = "rename",  .fn = dm_dev_rename_ioctl},
 125                 { .cmd = "resume",  .fn = dm_dev_resume_ioctl},
 126                 { .cmd = "clear",   .fn = dm_table_clear_ioctl},
 127                 { .cmd = "deps",    .fn = dm_table_deps_ioctl},
 128                 { .cmd = "reload",  .fn = dm_table_load_ioctl},
 129                 { .cmd = "status",  .fn = dm_table_status_ioctl},
 130                 { .cmd = "table",   .fn = dm_table_status_ioctl},
 131                 {NULL, NULL}
 132 };
 133
 134 /* New module handle routine */
 135 static int
 136 dm_modcmd(module_t mod, int cmd, void *unused)
 137 {
 138         int error, bmajor, cmajor;
 139
 140         error = 0;
 141         bmajor = -1;
 142         cmajor = -1;
 143
 144         switch (cmd) {
 145         case MOD_LOAD:
 146                 devfs_clone_bitmap_init(&dm_minor_bitmap);
 147                 dm_doinit();
 148                 kprintf("Device Mapper version %d.%d.%d loaded\n",
 149                     DM_VERSION_MAJOR, DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL);
 150                 break;
 151
 152         case MOD_UNLOAD:
 153                 /*
 154                  * Disable unloading of dm module if there are any devices
 155                  * defined in driver. This is probably too strong we need
 156                  * to disable auto-unload only if there is mounted dm device
 157                  * present.
 158                  */
 159                 if (dm_dev_counter > 0)
 160                         return EBUSY;
 161
 162                 error = dmdestroy();
 163                 if (error)
 164                         break;
 165                 kprintf("Device Mapper unloaded\n");
 166                 break;
 167
 168         default:
 169                 break;
 170         }
 171
 172         return error;
 173 }
 174
 175 /*
 176  * dm_detach is called to completely destroy & remove a dm disk device.
 177  */
 178 int
 179 dm_detach(dm_dev_t *dmv)
 180 {
 181         int minor;
 182
 183         /* Remove device from list and wait for refcnt to drop to zero */
 184         dm_dev_rem(dmv, NULL, NULL, -1);
 185
 186         /* Destroy active table first.  */
 187         dm_table_destroy(&dmv->table_head, DM_TABLE_ACTIVE);
 188
 189         /* Destroy inactive table if exits, too. */
 190         dm_table_destroy(&dmv->table_head, DM_TABLE_INACTIVE);
 191
 192         dm_table_head_destroy(&dmv->table_head);
 193
 194         minor = dkunit(dmv->devt);
 195         disk_destroy(dmv->diskp);
 196         devstat_remove_entry(&dmv->stats);
 197
 198         release_dev(dmv->devt);
 199         devfs_clone_bitmap_put(&dm_minor_bitmap, minor);
 200
 201         /* Destroy device */
 202         (void)dm_dev_free(dmv);
 203
 204         /* Decrement device counter After removing device */
 205         --dm_dev_counter; /* XXX: was atomic 64 */
 206
 207         return 0;
 208 }
 209
 210 static void
 211 dm_doinit(void)
 212 {
 213         dm_target_init();
 214         dm_dev_init();
 215         dm_pdev_init();
 216         dmcdev = make_dev(&dm_ops, 0, UID_ROOT, GID_OPERATOR, 0640, "mapper/control");
 217 }
 218
 219 /* Destroy routine */
 220 static int
 221 dmdestroy(void)
 222 {
 223         destroy_dev(dmcdev);
 224
 225         dm_dev_destroy();
 226         dm_pdev_destroy();
 227         dm_target_destroy();
 228
 229         return 0;
 230 }
 231
 232 static int
 233 dmopen(struct dev_open_args *ap)
 234 {
 235         cdev_t dev = ap->a_head.a_dev;
 236         dm_dev_t *dmv;
 237
 238         /* Shortcut for the control device */
 239         if (minor(dev) == 0)
 240                 return 0;
 241
 242         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 243                 return ENXIO;
 244
 245         dmv->is_open = 1;
 246         dm_dev_unbusy(dmv);
 247
 248         aprint_debug("dm open routine called %" PRIu32 "\n",
 249             minor(ap->a_head.a_dev));
 250         return 0;
 251 }
 252
 253 static int
 254 dmclose(struct dev_close_args *ap)
 255 {
 256         cdev_t dev = ap->a_head.a_dev;
 257         dm_dev_t *dmv;
 258
 259         /* Shortcut for the control device */
 260         if (minor(dev) == 0)
 261                 return 0;
 262
 263         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 264                 return ENXIO;
 265
 266         dmv->is_open = 0;
 267         dm_dev_unbusy(dmv);
 268
 269         aprint_debug("dm close routine called %" PRIu32 "\n",
 270             minor(ap->a_head.a_dev));
 271         return 0;
 272 }
 273
 274
 275 static int
 276 dmioctl(struct dev_ioctl_args *ap)
 277 {
 278         cdev_t dev = ap->a_head.a_dev;
 279         u_long cmd = ap->a_cmd;
 280         void *data = ap->a_data;
 281
 282         int r, err;
 283         prop_dictionary_t dm_dict_in;
 284
 285         err = r = 0;
 286
 287         aprint_debug("dmioctl called\n");
 288
 289         KKASSERT(data != NULL);
 290
 291         if (( r = disk_ioctl_switch(dev, cmd, data)) == ENOTTY) {
 292                 struct plistref *pref = (struct plistref *) data;
 293
 294                 /* Check if we were called with NETBSD_DM_IOCTL ioctl
 295                    otherwise quit. */
 296                 if ((r = dm_ioctl_switch(cmd)) != 0)
 297                         return r;
 298
 299                 if((r = prop_dictionary_copyin_ioctl(pref, cmd, &dm_dict_in)) != 0)
 300                         return r;
 301
 302                 if ((r = dm_check_version(dm_dict_in)) != 0)
 303                         goto cleanup_exit;
 304
 305                 /* run ioctl routine */
 306                 if ((err = dm_cmd_to_fun(dm_dict_in)) != 0)
 307                         goto cleanup_exit;
 308
 309 cleanup_exit:
 310                 r = prop_dictionary_copyout_ioctl(pref, cmd, dm_dict_in);
 311                 prop_object_release(dm_dict_in);
 312         }
 313
 314         /*
 315          * Return the error of the actual command if one one has
 316          * happened. Otherwise return 'r' which indicates errors
 317          * that occurred during helper operations.
 318          */
 319         return (err != 0)?err:r;
 320 }
 321
 322 /*
 323  * Translate command sent from libdevmapper to func.
 324  */
 325 static int
 326 dm_cmd_to_fun(prop_dictionary_t dm_dict){
 327         int i, r;
 328         prop_string_t command;
 329
 330         r = 0;
 331
 332         if ((command = prop_dictionary_get(dm_dict, DM_IOCTL_COMMAND)) == NULL)
 333                 return EINVAL;
 334
 335         for(i = 0; cmd_fn[i].cmd != NULL; i++)
 336                 if (prop_string_equals_cstring(command, cmd_fn[i].cmd))
 337                         break;
 338
 339         if (cmd_fn[i].cmd == NULL)
 340                 return EINVAL;
 341
 342         aprint_debug("ioctl %s called\n", cmd_fn[i].cmd);
 343         r = cmd_fn[i].fn(dm_dict);
 344
 345         return r;
 346 }
 347
 348 /* Call apropriate ioctl handler function. */
 349 static int
 350 dm_ioctl_switch(u_long cmd)
 351 {
 352
 353         switch(cmd) {
 354
 355         case NETBSD_DM_IOCTL:
 356                 aprint_debug("dm NetBSD_DM_IOCTL called\n");
 357                 break;
 358         default:
 359                  aprint_debug("dm unknown ioctl called\n");
 360                  return ENOTTY;
 361                  break; /* NOT REACHED */
 362         }
 363
 364          return 0;
 365 }
 366
 367  /*
 368   * Check for disk specific ioctls.
 369   */
 370
 371 static int
 372 disk_ioctl_switch(cdev_t dev, u_long cmd, void *data)
 373 {
 374         dm_dev_t *dmv;
 375
 376         /* disk ioctls make sense only on block devices */
 377         if (minor(dev) == 0)
 378                 return ENOTTY;
 379
 380         switch(cmd) {
 381         case DIOCGPART:
 382         {
 383                 struct partinfo *dpart;
 384                 u_int64_t size;
 385                 dpart = (void *)data;
 386                 bzero(dpart, sizeof(*dpart));
 387
 388                 if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 389                         return ENODEV;
 390                 if (dmv->diskp->d_info.d_media_blksize == 0) {
 391                         dm_dev_unbusy(dmv);
 392                         return ENOTSUP;
 393                 } else {
 394                         size = dm_table_size(&dmv->table_head);
 395                         dpart->media_offset  = 0;
 396                         dpart->media_size    = size * DEV_BSIZE;
 397                         dpart->media_blocks  = size;
 398                         dpart->media_blksize = DEV_BSIZE;
 399                         dpart->fstype = FS_BSDFFS;
 400                 }
 401                 dm_dev_unbusy(dmv);
 402                 break;
 403         }
 404
 405         default:
 406                 aprint_debug("unknown disk_ioctl called\n");
 407                 return ENOTTY;
 408                 break; /* NOT REACHED */
 409         }
 410
 411         return 0;
 412 }
 413
 414 /*
 415  * Do all IO operations on dm logical devices.
 416  */
 417 static int
 418 dmstrategy(struct dev_strategy_args *ap)
 419 {
 420         cdev_t dev = ap->a_head.a_dev;
 421         struct bio *bio = ap->a_bio;
 422         struct buf *bp = bio->bio_buf;
 423         int bypass;
 424
 425         dm_dev_t *dmv;
 426         dm_table_t  *tbl;
 427         dm_table_entry_t *table_en;
 428         struct buf *nestbuf;
 429
 430         uint32_t dev_type;
 431
 432         uint64_t buf_start, buf_len, issued_len;
 433         uint64_t table_start, table_end;
 434         uint64_t start, end;
 435
 436         buf_start = bio->bio_offset;
 437         buf_len = bp->b_bcount;
 438
 439         tbl = NULL;
 440
 441         table_end = 0;
 442         dev_type = 0;
 443         issued_len = 0;
 444
 445         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL) {
 446                 bp->b_error = EIO;
 447                 bp->b_resid = bp->b_bcount;
 448                 biodone(bio);
 449                 return 0;
 450         }
 451
 452         switch(bp->b_cmd) {
 453         case BUF_CMD_READ:
 454         case BUF_CMD_WRITE:
 455         case BUF_CMD_FREEBLKS:
 456                 bypass = 0;
 457                 break;
 458         case BUF_CMD_FLUSH:
 459                 bypass = 1;
 460                 KKASSERT(buf_len == 0);
 461                 break;
 462         default:
 463                 dm_dev_unbusy(dmv);
 464                 bp->b_error = EIO;
 465                 bp->b_resid = bp->b_bcount;
 466                 biodone(bio);
 467                 return 0;
 468         }
 469
 470         if (bypass == 0 &&
 471             bounds_check_with_mediasize(bio, DEV_BSIZE,
 472                                         dm_table_size(&dmv->table_head)) <= 0) {
 473                 dm_dev_unbusy(dmv);
 474                 bp->b_resid = bp->b_bcount;
 475                 biodone(bio);
 476                 return 0;
 477         }
 478
 479         /* Select active table */
 480         tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
 481
 482         nestiobuf_init(bio);
 483         devstat_start_transaction(&dmv->stats);
 484
 485         /*
 486          * Find out what tables I want to select.
 487          */
 488         SLIST_FOREACH(table_en, tbl, next) {
 489                 /*
 490                  * I need need number of bytes not blocks.
 491                  */
 492                 table_start = table_en->start * DEV_BSIZE;
 493                 table_end = table_start + (table_en->length) * DEV_BSIZE;
 494
 495                 /*
 496                  * Calculate the start and end
 497                  */
 498                 start = MAX(table_start, buf_start);
 499                 end = MIN(table_end, buf_start + buf_len);
 500
 501                 aprint_debug("----------------------------------------\n");
 502                 aprint_debug("table_start %010" PRIu64", table_end %010"
 503                     PRIu64 "\n", table_start, table_end);
 504                 aprint_debug("buf_start %010" PRIu64", buf_len %010"
 505                     PRIu64"\n", buf_start, buf_len);
 506                 aprint_debug("start-buf_start %010"PRIu64", end %010"
 507                     PRIu64"\n", start - buf_start, end);
 508                 aprint_debug("start %010" PRIu64" , end %010"
 509                     PRIu64"\n", start, end);
 510                 aprint_debug("\n----------------------------------------\n");
 511
 512                 if (bypass) {
 513                         nestbuf = getpbuf(NULL);
 514                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 515
 516                         nestiobuf_add(bio, nestbuf, 0, 0, &dmv->stats);
 517                         nestbuf->b_bio1.bio_offset = 0;
 518                         table_en->target->strategy(table_en, nestbuf);
 519                 } else if (start < end) {
 520                         nestbuf = getpbuf(NULL);
 521                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 522
 523                         nestiobuf_add(bio, nestbuf,
 524                                       start - buf_start, (end - start),
 525                                       &dmv->stats);
 526                         issued_len += end - start;
 527
 528                         nestbuf->b_bio1.bio_offset = (start - table_start);
 529                         table_en->target->strategy(table_en, nestbuf);
 530                 }
 531         }
 532
 533         if (issued_len < buf_len)
 534                 nestiobuf_error(bio, EINVAL);
 535         nestiobuf_start(bio);
 536         dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
 537         dm_dev_unbusy(dmv);
 538
 539         return 0;
 540 }
 541
 542 static int
 543 dmdump(struct dev_dump_args *ap)
 544 {
 545         cdev_t dev = ap->a_head.a_dev;
 546         dm_dev_t *dmv;
 547         dm_table_t  *tbl;
 548         dm_table_entry_t *table_en;
 549         uint32_t dev_type;
 550         uint64_t buf_start, buf_len, issued_len;
 551         uint64_t table_start, table_end;
 552         uint64_t start, end, data_offset;
 553         off_t offset;
 554         size_t length;
 555         int error = 0;
 556
 557         buf_start = ap->a_offset;
 558         buf_len = ap->a_length;
 559
 560         tbl = NULL;
 561
 562         table_end = 0;
 563         dev_type = 0;
 564         issued_len = 0;
 565
 566         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL) {
 567                 return EIO;
 568         }
 569
 570         /* Select active table */
 571         tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
 572
 573
 574         /*
 575          * Find out what tables I want to select.
 576          */
 577         SLIST_FOREACH(table_en, tbl, next) {
 578                 /*
 579                  * I need need number of bytes not blocks.
 580                  */
 581                 table_start = table_en->start * DEV_BSIZE;
 582                 table_end = table_start + (table_en->length) * DEV_BSIZE;
 583
 584                 /*
 585                  * Calculate the start and end
 586                  */
 587                 start = MAX(table_start, buf_start);
 588                 end = MIN(table_end, buf_start + buf_len);
 589
 590                 if (ap->a_length == 0) {
 591                         if (table_en->target->dump == NULL) {
 592                                 error = ENXIO;
 593                                 goto out;
 594                         }
 595
 596                         table_en->target->dump(table_en, NULL, 0, 0);
 597                 } else if (start < end) {
 598                         data_offset = start - buf_start;
 599                         offset = start - table_start;
 600                         length = end - start;
 601
 602                         if (table_en->target->dump == NULL) {
 603                                 error = ENXIO;
 604                                 goto out;
 605                         }
 606
 607                         table_en->target->dump(table_en,
 608                             (char *)ap->a_virtual + data_offset,
 609                             length, offset);
 610
 611                         issued_len += end - start;
 612                 }
 613         }
 614
 615         if (issued_len < buf_len)
 616                 error = EINVAL;
 617
 618 out:
 619         dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
 620         dm_dev_unbusy(dmv);
 621
 622         return error;
 623 }
 624
 625 static int
 626 dmsize(struct dev_psize_args *ap)
 627 {
 628         cdev_t dev = ap->a_head.a_dev;
 629         dm_dev_t *dmv;
 630         uint64_t size;
 631
 632         size = 0;
 633
 634         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 635                         return ENOENT;
 636
 637         size = dm_table_size(&dmv->table_head);
 638         dm_dev_unbusy(dmv);
 639
 640         ap->a_result = (int64_t)size;
 641
 642         return 0;
 643 }
 644
 645 #if 0
 646 static void
 647 dmminphys(struct buf *bp)
 648 {
 649
 650         bp->b_bcount = MIN(bp->b_bcount, MAXPHYS);
 651 }
 652 #endif
 653
 654 void
 655 dmsetdiskinfo(struct disk *disk, dm_table_head_t *head)
 656 {
 657         struct disk_info info;
 658         uint64_t dmp_size;
 659
 660         dmp_size = dm_table_size(head);
 661
 662         bzero(&info, sizeof(struct disk_info));
 663         info.d_media_blksize = DEV_BSIZE;
 664         info.d_media_blocks = dmp_size;
 665 #if 0
 666         /* this is set by disk_setdiskinfo */
 667         info.d_media_size = dmp_size * DEV_BSIZE;
 668 #endif
 669         info.d_dsflags = DSO_MBRQUIET | DSO_DEVICEMAPPER;
 670
 671         info.d_secpertrack = 32;
 672         info.d_nheads = 64;
 673         info.d_secpercyl = info.d_secpertrack * info.d_nheads;
 674         info.d_ncylinders = dmp_size / info.d_secpercyl;
 675
 676         disk_setdiskinfo(disk, &info);
 677 }
 678
 679 TUNABLE_INT("debug.dm_debug", &dm_debug_level);
 680 SYSCTL_INT(_debug, OID_AUTO, dm_debug, CTLFLAG_RW, &dm_debug_level,
 681                0, "Eanble device mapper debugging");
 682