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/disk.h>
  43 #include <sys/disklabel.h>
  44 #include <sys/dtype.h>
  45 #include <sys/ioccom.h>
  46 #include <sys/malloc.h>
  47 #include <sys/module.h>
  48 #include <sys/sysctl.h>
  49 #include <dev/disk/dm/dm.h>
  50
  51 #include "netbsd-dm.h"
  52
  53 static  d_ioctl_t       dmioctl;
  54 static  d_open_t        dmopen;
  55 static  d_close_t       dmclose;
  56 static  d_psize_t       dmsize;
  57 static  d_strategy_t    dmstrategy;
  58 static  d_dump_t        dmdump;
  59
  60 /* attach and detach routines */
  61 void dmattach(int);
  62 static int dm_modcmd(module_t mod, int cmd, void *unused);
  63 static int dmdestroy(void);
  64
  65 static void dm_doinit(void);
  66
  67 static int dm_cmd_to_fun(prop_dictionary_t);
  68 static int disk_ioctl_switch(cdev_t, u_long, void *);
  69 static int dm_ioctl_switch(u_long);
  70 #if 0
  71 static void dmminphys(struct buf *);
  72 #endif
  73
  74 /* ***Variable-definitions*** */
  75 struct dev_ops dm_ops = {
  76         { "dm", 0, D_DISK | D_MPSAFE },
  77         .d_open         = dmopen,
  78         .d_close        = dmclose,
  79         .d_read         = physread,
  80         .d_write        = physwrite,
  81         .d_ioctl        = dmioctl,
  82         .d_strategy     = dmstrategy,
  83         .d_psize        = dmsize,
  84         .d_dump         = dmdump,
  85 /* D_DISK */
  86 };
  87
  88 MALLOC_DEFINE(M_DM, "dm", "Device Mapper allocations");
  89
  90 int dm_debug_level = 0;
  91
  92 extern uint64_t dm_dev_counter;
  93
  94 static cdev_t dmcdev;
  95
  96 static moduledata_t dm_mod = {
  97     "dm",
  98     dm_modcmd,
  99     NULL
 100 };
 101 DECLARE_MODULE(dm, dm_mod, SI_SUB_RAID, SI_ORDER_ANY);
 102 MODULE_VERSION(dm, 1);
 103
 104 /*
 105  * This array is used to translate cmd to function pointer.
 106  *
 107  * Interface between libdevmapper and lvm2tools uses different
 108  * names for one IOCTL call because libdevmapper do another thing
 109  * then. When I run "info" or "mknodes" libdevmapper will send same
 110  * ioctl to kernel but will do another things in userspace.
 111  *
 112  */
 113 static struct cmd_function cmd_fn[] = {
 114                 { .cmd = "version", .fn = dm_get_version_ioctl},
 115                 { .cmd = "targets", .fn = dm_list_versions_ioctl},
 116                 { .cmd = "create",  .fn = dm_dev_create_ioctl},
 117                 { .cmd = "info",    .fn = dm_dev_status_ioctl},
 118                 { .cmd = "mknodes", .fn = dm_dev_status_ioctl},
 119                 { .cmd = "names",   .fn = dm_dev_list_ioctl},
 120                 { .cmd = "suspend", .fn = dm_dev_suspend_ioctl},
 121                 { .cmd = "remove",  .fn = dm_dev_remove_ioctl},
 122                 { .cmd = "remove_all", .fn = dm_dev_remove_all_ioctl},
 123                 { .cmd = "rename",  .fn = dm_dev_rename_ioctl},
 124                 { .cmd = "resume",  .fn = dm_dev_resume_ioctl},
 125                 { .cmd = "clear",   .fn = dm_table_clear_ioctl},
 126                 { .cmd = "deps",    .fn = dm_table_deps_ioctl},
 127                 { .cmd = "reload",  .fn = dm_table_load_ioctl},
 128                 { .cmd = "status",  .fn = dm_table_status_ioctl},
 129                 { .cmd = "table",   .fn = dm_table_status_ioctl},
 130                 {NULL, NULL}
 131 };
 132
 133 /* New module handle routine */
 134 static int
 135 dm_modcmd(module_t mod, int cmd, void *unused)
 136 {
 137         int error, bmajor, cmajor;
 138
 139         error = 0;
 140         bmajor = -1;
 141         cmajor = -1;
 142
 143         switch (cmd) {
 144         case MOD_LOAD:
 145                 dm_doinit();
 146                 kprintf("Device Mapper version %d.%d.%d loaded\n",
 147                     DM_VERSION_MAJOR, DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL);
 148                 break;
 149
 150         case MOD_UNLOAD:
 151                 /*
 152                  * Disable unloading of dm module if there are any devices
 153                  * defined in driver. This is probably too strong we need
 154                  * to disable auto-unload only if there is mounted dm device
 155                  * present.
 156                  */
 157                 if (dm_dev_counter > 0)
 158                         return EBUSY;
 159
 160                 error = dmdestroy();
 161                 if (error)
 162                         break;
 163                 kprintf("Device Mapper unloaded\n");
 164                 break;
 165
 166         default:
 167                 break;
 168         }
 169
 170         return error;
 171 }
 172
 173 static void
 174 dm_doinit(void)
 175 {
 176         dm_target_init();
 177         dm_dev_init();
 178         dm_pdev_init();
 179         dmcdev = make_dev(&dm_ops, 0, UID_ROOT, GID_OPERATOR, 0640, "mapper/control");
 180 }
 181
 182 /* Destroy routine */
 183 static int
 184 dmdestroy(void)
 185 {
 186         destroy_dev(dmcdev);
 187
 188         dm_dev_uninit();
 189         dm_pdev_uninit();
 190         dm_target_uninit();
 191
 192         return 0;
 193 }
 194
 195 static int
 196 dmopen(struct dev_open_args *ap)
 197 {
 198         cdev_t dev = ap->a_head.a_dev;
 199         dm_dev_t *dmv;
 200
 201         /* Shortcut for the control device */
 202         if (minor(dev) == 0)
 203                 return 0;
 204
 205         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 206                 return ENXIO;
 207
 208         dmv->is_open = 1;
 209         dm_dev_unbusy(dmv);
 210
 211         aprint_debug("dm open routine called %" PRIu32 "\n",
 212             minor(ap->a_head.a_dev));
 213         return 0;
 214 }
 215
 216 static int
 217 dmclose(struct dev_close_args *ap)
 218 {
 219         cdev_t dev = ap->a_head.a_dev;
 220         dm_dev_t *dmv;
 221
 222         /* Shortcut for the control device */
 223         if (minor(dev) == 0)
 224                 return 0;
 225
 226         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 227                 return ENXIO;
 228
 229         dmv->is_open = 0;
 230         dm_dev_unbusy(dmv);
 231
 232         aprint_debug("dm close routine called %" PRIu32 "\n",
 233             minor(ap->a_head.a_dev));
 234         return 0;
 235 }
 236
 237
 238 static int
 239 dmioctl(struct dev_ioctl_args *ap)
 240 {
 241         cdev_t dev = ap->a_head.a_dev;
 242         u_long cmd = ap->a_cmd;
 243         void *data = ap->a_data;
 244
 245         int r, err;
 246         prop_dictionary_t dm_dict_in;
 247
 248         err = r = 0;
 249
 250         aprint_debug("dmioctl called\n");
 251
 252         KKASSERT(data != NULL);
 253
 254         if (( r = disk_ioctl_switch(dev, cmd, data)) == ENOTTY) {
 255                 struct plistref *pref = (struct plistref *) data;
 256
 257                 /* Check if we were called with NETBSD_DM_IOCTL ioctl
 258                    otherwise quit. */
 259                 if ((r = dm_ioctl_switch(cmd)) != 0)
 260                         return r;
 261
 262                 if((r = prop_dictionary_copyin_ioctl(pref, cmd, &dm_dict_in)) != 0)
 263                         return r;
 264
 265                 if ((r = dm_check_version(dm_dict_in)) != 0)
 266                         goto cleanup_exit;
 267
 268                 /* run ioctl routine */
 269                 if ((err = dm_cmd_to_fun(dm_dict_in)) != 0)
 270                         goto cleanup_exit;
 271
 272 cleanup_exit:
 273                 r = prop_dictionary_copyout_ioctl(pref, cmd, dm_dict_in);
 274                 prop_object_release(dm_dict_in);
 275         }
 276
 277         /*
 278          * Return the error of the actual command if one one has
 279          * happened. Otherwise return 'r' which indicates errors
 280          * that occurred during helper operations.
 281          */
 282         return (err != 0)?err:r;
 283 }
 284
 285 /*
 286  * Translate command sent from libdevmapper to func.
 287  */
 288 static int
 289 dm_cmd_to_fun(prop_dictionary_t dm_dict){
 290         int i, r;
 291         prop_string_t command;
 292
 293         r = 0;
 294
 295         if ((command = prop_dictionary_get(dm_dict, DM_IOCTL_COMMAND)) == NULL)
 296                 return EINVAL;
 297
 298         for(i = 0; cmd_fn[i].cmd != NULL; i++)
 299                 if (prop_string_equals_cstring(command, cmd_fn[i].cmd))
 300                         break;
 301
 302         if (cmd_fn[i].cmd == NULL)
 303                 return EINVAL;
 304
 305         aprint_debug("ioctl %s called\n", cmd_fn[i].cmd);
 306         r = cmd_fn[i].fn(dm_dict);
 307
 308         return r;
 309 }
 310
 311 /* Call apropriate ioctl handler function. */
 312 static int
 313 dm_ioctl_switch(u_long cmd)
 314 {
 315
 316         switch(cmd) {
 317
 318         case NETBSD_DM_IOCTL:
 319                 aprint_debug("dm NetBSD_DM_IOCTL called\n");
 320                 break;
 321         default:
 322                  aprint_debug("dm unknown ioctl called\n");
 323                  return ENOTTY;
 324                  break; /* NOT REACHED */
 325         }
 326
 327          return 0;
 328 }
 329
 330  /*
 331   * Check for disk specific ioctls.
 332   */
 333
 334 static int
 335 disk_ioctl_switch(cdev_t dev, u_long cmd, void *data)
 336 {
 337         dm_dev_t *dmv;
 338
 339         /* disk ioctls make sense only on block devices */
 340         if (minor(dev) == 0)
 341                 return ENOTTY;
 342
 343         switch(cmd) {
 344         case DIOCGPART:
 345         {
 346                 struct partinfo *dpart;
 347                 u_int64_t size;
 348                 dpart = (void *)data;
 349                 bzero(dpart, sizeof(*dpart));
 350
 351                 if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 352                         return ENODEV;
 353                 if (dmv->diskp->d_info.d_media_blksize == 0) {
 354                         dm_dev_unbusy(dmv);
 355                         return ENOTSUP;
 356                 } else {
 357                         size = dm_table_size(&dmv->table_head);
 358                         dpart->media_offset  = 0;
 359                         dpart->media_size    = size * DEV_BSIZE;
 360                         dpart->media_blocks  = size;
 361                         dpart->media_blksize = DEV_BSIZE;
 362                         dpart->fstype = FS_BSDFFS;
 363                 }
 364                 dm_dev_unbusy(dmv);
 365                 break;
 366         }
 367
 368         default:
 369                 aprint_debug("unknown disk_ioctl called\n");
 370                 return ENOTTY;
 371                 break; /* NOT REACHED */
 372         }
 373
 374         return 0;
 375 }
 376
 377 /*
 378  * Do all IO operations on dm logical devices.
 379  */
 380 static int
 381 dmstrategy(struct dev_strategy_args *ap)
 382 {
 383         cdev_t dev = ap->a_head.a_dev;
 384         struct bio *bio = ap->a_bio;
 385         struct buf *bp = bio->bio_buf;
 386         int bypass;
 387
 388         dm_dev_t *dmv;
 389         dm_table_t  *tbl;
 390         dm_table_entry_t *table_en;
 391         struct buf *nestbuf;
 392
 393         uint32_t dev_type;
 394
 395         uint64_t buf_start, buf_len, issued_len;
 396         uint64_t table_start, table_end;
 397         uint64_t start, end;
 398
 399         buf_start = bio->bio_offset;
 400         buf_len = bp->b_bcount;
 401
 402         tbl = NULL;
 403
 404         table_end = 0;
 405         dev_type = 0;
 406         issued_len = 0;
 407
 408         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL) {
 409                 bp->b_error = EIO;
 410                 bp->b_resid = bp->b_bcount;
 411                 biodone(bio);
 412                 return 0;
 413         }
 414
 415         switch(bp->b_cmd) {
 416         case BUF_CMD_READ:
 417         case BUF_CMD_WRITE:
 418         case BUF_CMD_FREEBLKS:
 419                 bypass = 0;
 420                 break;
 421         case BUF_CMD_FLUSH:
 422                 bypass = 1;
 423                 KKASSERT(buf_len == 0);
 424                 break;
 425         default:
 426                 dm_dev_unbusy(dmv);
 427                 bp->b_error = EIO;
 428                 bp->b_resid = bp->b_bcount;
 429                 biodone(bio);
 430                 return 0;
 431         }
 432
 433         if (bypass == 0 &&
 434             bounds_check_with_mediasize(bio, DEV_BSIZE,
 435                                         dm_table_size(&dmv->table_head)) <= 0) {
 436                 dm_dev_unbusy(dmv);
 437                 bp->b_resid = bp->b_bcount;
 438                 biodone(bio);
 439                 return 0;
 440         }
 441
 442         /* Select active table */
 443         tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
 444
 445         nestiobuf_init(bio);
 446         devstat_start_transaction(&dmv->stats);
 447
 448         /*
 449          * Find out what tables I want to select.
 450          */
 451         SLIST_FOREACH(table_en, tbl, next) {
 452                 /*
 453                  * I need need number of bytes not blocks.
 454                  */
 455                 table_start = table_en->start * DEV_BSIZE;
 456                 table_end = table_start + (table_en->length) * DEV_BSIZE;
 457
 458                 /*
 459                  * Calculate the start and end
 460                  */
 461                 start = MAX(table_start, buf_start);
 462                 end = MIN(table_end, buf_start + buf_len);
 463
 464                 aprint_debug("----------------------------------------\n");
 465                 aprint_debug("table_start %010" PRIu64", table_end %010"
 466                     PRIu64 "\n", table_start, table_end);
 467                 aprint_debug("buf_start %010" PRIu64", buf_len %010"
 468                     PRIu64"\n", buf_start, buf_len);
 469                 aprint_debug("start-buf_start %010"PRIu64", end %010"
 470                     PRIu64"\n", start - buf_start, end);
 471                 aprint_debug("start %010" PRIu64" , end %010"
 472                     PRIu64"\n", start, end);
 473                 aprint_debug("\n----------------------------------------\n");
 474
 475                 if (bypass) {
 476                         nestbuf = getpbuf(NULL);
 477                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 478
 479                         nestiobuf_add(bio, nestbuf, 0, 0, &dmv->stats);
 480                         nestbuf->b_bio1.bio_offset = 0;
 481                         table_en->target->strategy(table_en, nestbuf);
 482                 } else if (start < end) {
 483                         nestbuf = getpbuf(NULL);
 484                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 485
 486                         nestiobuf_add(bio, nestbuf,
 487                                       start - buf_start, (end - start),
 488                                       &dmv->stats);
 489                         issued_len += end - start;
 490
 491                         nestbuf->b_bio1.bio_offset = (start - table_start);
 492                         table_en->target->strategy(table_en, nestbuf);
 493                 }
 494         }
 495
 496         if (issued_len < buf_len)
 497                 nestiobuf_error(bio, EINVAL);
 498         nestiobuf_start(bio);
 499         dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
 500         dm_dev_unbusy(dmv);
 501
 502         return 0;
 503 }
 504
 505 static int
 506 dmdump(struct dev_dump_args *ap)
 507 {
 508         cdev_t dev = ap->a_head.a_dev;
 509         dm_dev_t *dmv;
 510         dm_table_t  *tbl;
 511         dm_table_entry_t *table_en;
 512         uint32_t dev_type;
 513         uint64_t buf_start, buf_len, issued_len;
 514         uint64_t table_start, table_end;
 515         uint64_t start, end, data_offset;
 516         off_t offset;
 517         size_t length;
 518         int error = 0;
 519
 520         buf_start = ap->a_offset;
 521         buf_len = ap->a_length;
 522
 523         tbl = NULL;
 524
 525         table_end = 0;
 526         dev_type = 0;
 527         issued_len = 0;
 528
 529         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL) {
 530                 return EIO;
 531         }
 532
 533         /* Select active table */
 534         tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
 535
 536
 537         /*
 538          * Find out what tables I want to select.
 539          */
 540         SLIST_FOREACH(table_en, tbl, next) {
 541                 /*
 542                  * I need need number of bytes not blocks.
 543                  */
 544                 table_start = table_en->start * DEV_BSIZE;
 545                 table_end = table_start + (table_en->length) * DEV_BSIZE;
 546
 547                 /*
 548                  * Calculate the start and end
 549                  */
 550                 start = MAX(table_start, buf_start);
 551                 end = MIN(table_end, buf_start + buf_len);
 552
 553                 if (ap->a_length == 0) {
 554                         if (table_en->target->dump == NULL) {
 555                                 error = ENXIO;
 556                                 goto out;
 557                         }
 558
 559                         table_en->target->dump(table_en, NULL, 0, 0);
 560                 } else if (start < end) {
 561                         data_offset = start - buf_start;
 562                         offset = start - table_start;
 563                         length = end - start;
 564
 565                         if (table_en->target->dump == NULL) {
 566                                 error = ENXIO;
 567                                 goto out;
 568                         }
 569
 570                         table_en->target->dump(table_en,
 571                             (char *)ap->a_virtual + data_offset,
 572                             length, offset);
 573
 574                         issued_len += end - start;
 575                 }
 576         }
 577
 578         if (issued_len < buf_len)
 579                 error = EINVAL;
 580
 581 out:
 582         dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
 583         dm_dev_unbusy(dmv);
 584
 585         return error;
 586 }
 587
 588 static int
 589 dmsize(struct dev_psize_args *ap)
 590 {
 591         cdev_t dev = ap->a_head.a_dev;
 592         dm_dev_t *dmv;
 593         uint64_t size;
 594
 595         size = 0;
 596
 597         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 598                         return ENOENT;
 599
 600         size = dm_table_size(&dmv->table_head);
 601         dm_dev_unbusy(dmv);
 602
 603         ap->a_result = (int64_t)size;
 604
 605         return 0;
 606 }
 607
 608 #if 0
 609 static void
 610 dmminphys(struct buf *bp)
 611 {
 612
 613         bp->b_bcount = MIN(bp->b_bcount, MAXPHYS);
 614 }
 615 #endif
 616
 617 void
 618 dmsetdiskinfo(struct disk *disk, dm_table_head_t *head)
 619 {
 620         struct disk_info info;
 621         uint64_t dmp_size;
 622
 623         dmp_size = dm_table_size(head);
 624
 625         bzero(&info, sizeof(struct disk_info));
 626         info.d_media_blksize = DEV_BSIZE;
 627         info.d_media_blocks = dmp_size;
 628 #if 0
 629         /* this is set by disk_setdiskinfo */
 630         info.d_media_size = dmp_size * DEV_BSIZE;
 631 #endif
 632         info.d_dsflags = DSO_MBRQUIET | DSO_DEVICEMAPPER;
 633
 634         info.d_secpertrack = 32;
 635         info.d_nheads = 64;
 636         info.d_secpercyl = info.d_secpertrack * info.d_nheads;
 637         info.d_ncylinders = dmp_size / info.d_secpercyl;
 638
 639         disk_setdiskinfo(disk, &info);
 640 }
 641
 642 /*
 643  * Transform char s to uint64_t offset number.
 644  */
 645 uint64_t
 646 atoi64(const char *s)
 647 {
 648         uint64_t n;
 649         n = 0;
 650
 651         while (*s != '\0') {
 652                 if (!isdigit(*s))
 653                         break;
 654
 655                 n = (10 * n) + (*s - '0');
 656                 s++;
 657         }
 658
 659         return n;
 660 }
 661
 662 void
 663 dm_builtin_init(void *arg)
 664 {
 665         modeventhand_t evh = (modeventhand_t)arg;
 666
 667         KKASSERT(evh != NULL);
 668         evh(NULL, MOD_LOAD, NULL);
 669 }
 670
 671 void
 672 dm_builtin_uninit(void *arg)
 673 {
 674         modeventhand_t evh = (modeventhand_t)arg;
 675
 676         KKASSERT(evh != NULL);
 677         evh(NULL, MOD_UNLOAD, NULL);
 678 }
 679
 680 TUNABLE_INT("debug.dm_debug", &dm_debug_level);
 681 SYSCTL_INT(_debug, OID_AUTO, dm_debug, CTLFLAG_RW, &dm_debug_level,
 682                0, "Eanble device mapper debugging");
 683