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/types.h>
  38 #include <sys/ctype.h>
  39
  40 #include <sys/buf.h>
  41 #include <sys/conf.h>
  42 #include <sys/device.h>
  43 #include <sys/disk.h>
  44 #include <sys/disklabel.h>
  45 #include <sys/dtype.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 /* New module handle and destroy routines */
  61 static int dm_modcmd(module_t mod, int cmd, void *unused);
  62 static int dmdestroy(void);
  63
  64 static void dm_doinit(void);
  65
  66 static int dm_cmd_to_fun(prop_dictionary_t);
  67 static int disk_ioctl_switch(cdev_t, u_long, void *);
  68 static int dm_ioctl_switch(u_long);
  69 #if 0
  70 static void dmminphys(struct buf *);
  71 #endif
  72
  73 /* ***Variable-definitions*** */
  74 struct dev_ops dm_ops = {
  75         { "dm", 0, D_DISK | D_MPSAFE },
  76         .d_open         = dmopen,
  77         .d_close        = dmclose,
  78         .d_read         = physread,
  79         .d_write        = physwrite,
  80         .d_ioctl        = dmioctl,
  81         .d_strategy     = dmstrategy,
  82         .d_psize        = dmsize,
  83         .d_dump         = dmdump,
  84 /* D_DISK */
  85 };
  86
  87 MALLOC_DEFINE(M_DM, "dm", "Device Mapper allocations");
  88
  89 int dm_debug_level = 0;
  90
  91 extern uint64_t dm_dev_counter;
  92
  93 static cdev_t dmcdev;
  94
  95 static moduledata_t dm_mod = {
  96     "dm",
  97     dm_modcmd,
  98     NULL
  99 };
 100 DECLARE_MODULE(dm, dm_mod, SI_SUB_RAID, SI_ORDER_ANY);
 101 MODULE_VERSION(dm, 1);
 102
 103 /*
 104  * This array is used to translate cmd to function pointer.
 105  *
 106  * Interface between libdevmapper and lvm2tools uses different
 107  * names for one IOCTL call because libdevmapper do another thing
 108  * then. When I run "info" or "mknodes" libdevmapper will send same
 109  * ioctl to kernel but will do another things in userspace.
 110  *
 111  */
 112 static struct cmd_function cmd_fn[] = {
 113                 { .cmd = "version", .fn = dm_get_version_ioctl},
 114                 { .cmd = "targets", .fn = dm_list_versions_ioctl},
 115                 { .cmd = "create",  .fn = dm_dev_create_ioctl},
 116                 { .cmd = "info",    .fn = dm_dev_status_ioctl},
 117                 { .cmd = "mknodes", .fn = dm_dev_status_ioctl},
 118                 { .cmd = "names",   .fn = dm_dev_list_ioctl},
 119                 { .cmd = "suspend", .fn = dm_dev_suspend_ioctl},
 120                 { .cmd = "remove",  .fn = dm_dev_remove_ioctl},
 121                 { .cmd = "remove_all", .fn = dm_dev_remove_all_ioctl},
 122                 { .cmd = "rename",  .fn = dm_dev_rename_ioctl},
 123                 { .cmd = "resume",  .fn = dm_dev_resume_ioctl},
 124                 { .cmd = "clear",   .fn = dm_table_clear_ioctl},
 125                 { .cmd = "deps",    .fn = dm_table_deps_ioctl},
 126                 { .cmd = "reload",  .fn = dm_table_load_ioctl},
 127                 { .cmd = "status",  .fn = dm_table_status_ioctl},
 128                 { .cmd = "table",   .fn = dm_table_status_ioctl},
 129                 { .cmd = "message", .fn = dm_message_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;
 138
 139         error = 0;
 140
 141         switch (cmd) {
 142         case MOD_LOAD:
 143                 dm_doinit();
 144                 kprintf("Device Mapper version %d.%d.%d loaded\n",
 145                     DM_VERSION_MAJOR, DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL);
 146                 break;
 147
 148         case MOD_UNLOAD:
 149                 /*
 150                  * Disable unloading of dm module if there are any devices
 151                  * defined in driver. This is probably too strong we need
 152                  * to disable auto-unload only if there is mounted dm device
 153                  * present.
 154                  */
 155                 if (dm_dev_counter > 0)
 156                         return EBUSY;
 157
 158                 error = dmdestroy();
 159                 if (error)
 160                         break;
 161                 kprintf("Device Mapper unloaded\n");
 162                 break;
 163
 164         default:
 165                 break;
 166         }
 167
 168         return error;
 169 }
 170
 171 static void
 172 dm_doinit(void)
 173 {
 174         dm_target_init();
 175         dm_dev_init();
 176         dm_pdev_init();
 177         dmcdev = make_dev(&dm_ops, 0, UID_ROOT, GID_OPERATOR, 0640, "mapper/control");
 178 }
 179
 180 /* Destroy routine */
 181 static int
 182 dmdestroy(void)
 183 {
 184         destroy_dev(dmcdev);
 185
 186         dm_dev_uninit();
 187         dm_pdev_uninit();
 188         dm_target_uninit();
 189
 190         return 0;
 191 }
 192
 193 static int
 194 dmopen(struct dev_open_args *ap)
 195 {
 196         cdev_t dev = ap->a_head.a_dev;
 197         dm_dev_t *dmv;
 198
 199         /* Shortcut for the control device */
 200         if (minor(dev) == 0)
 201                 return 0;
 202
 203         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 204                 return ENXIO;
 205
 206         dmv->is_open = 1;
 207         dm_dev_unbusy(dmv);
 208
 209         aprint_debug("dm open routine called %" PRIu32 "\n",
 210             minor(ap->a_head.a_dev));
 211         return 0;
 212 }
 213
 214 static int
 215 dmclose(struct dev_close_args *ap)
 216 {
 217         cdev_t dev = ap->a_head.a_dev;
 218         dm_dev_t *dmv;
 219
 220         /* Shortcut for the control device */
 221         if (minor(dev) == 0)
 222                 return 0;
 223
 224         if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
 225                 return ENXIO;
 226
 227         dmv->is_open = 0;
 228         dm_dev_unbusy(dmv);
 229
 230         aprint_debug("dm close routine called %" PRIu32 "\n",
 231             minor(ap->a_head.a_dev));
 232         return 0;
 233 }
 234
 235
 236 static int
 237 dmioctl(struct dev_ioctl_args *ap)
 238 {
 239         cdev_t dev = ap->a_head.a_dev;
 240         u_long cmd = ap->a_cmd;
 241         void *data = ap->a_data;
 242         struct plistref *pref = (struct plistref *)data;
 243
 244         int r, err;
 245         prop_dictionary_t dm_dict_in;
 246
 247         err = r = 0;
 248
 249         aprint_debug("dmioctl called\n");
 250         KKASSERT(data != NULL);
 251
 252         if ((r = disk_ioctl_switch(dev, cmd, data)) != ENOTTY)
 253                 return r;  /* Handled disk ioctl */
 254
 255         if ((r = dm_ioctl_switch(cmd)) != 0)
 256                 return r;  /* Not NETBSD_DM_IOCTL */
 257
 258         if ((r = prop_dictionary_copyin_ioctl(pref, cmd, &dm_dict_in)) != 0)
 259                 return r;
 260
 261         if ((r = dm_check_version(dm_dict_in)) == 0)
 262                 err = dm_cmd_to_fun(dm_dict_in);
 263
 264         r = prop_dictionary_copyout_ioctl(pref, cmd, dm_dict_in);
 265         prop_object_release(dm_dict_in);
 266
 267         /* Return the dm ioctl error if any. */
 268         if (err)
 269                 return err;
 270         return r;
 271 }
 272
 273 /*
 274  * Translate command sent from libdevmapper to func.
 275  */
 276 static int
 277 dm_cmd_to_fun(prop_dictionary_t dm_dict)
 278 {
 279         int i, r;
 280         prop_string_t command;
 281
 282         r = 0;
 283
 284         if ((command = prop_dictionary_get(dm_dict, DM_IOCTL_COMMAND)) == NULL)
 285                 return EINVAL;
 286
 287         for (i = 0; cmd_fn[i].cmd != NULL; i++)
 288                 if (prop_string_equals_cstring(command, cmd_fn[i].cmd))
 289                         break;
 290
 291         if (cmd_fn[i].cmd == NULL)
 292                 return EINVAL;
 293
 294         aprint_debug("ioctl %s called\n", cmd_fn[i].cmd);
 295         r = cmd_fn[i].fn(dm_dict);
 296
 297         return r;
 298 }
 299
 300 /* Call apropriate ioctl handler function. */
 301 static int
 302 dm_ioctl_switch(u_long cmd)
 303 {
 304
 305         switch(cmd) {
 306         case NETBSD_DM_IOCTL:
 307                 aprint_debug("dm NETBSD_DM_IOCTL called\n");
 308                 break;
 309         default:
 310                 aprint_debug("dm unknown ioctl called\n");
 311                 return ENOTTY;
 312                 break; /* NOT REACHED */
 313         }
 314
 315         return 0;
 316 }
 317
 318  /*
 319   * Check for disk specific ioctls.
 320   */
 321
 322 static int
 323 disk_ioctl_switch(cdev_t dev, u_long cmd, void *data)
 324 {
 325         dm_dev_t *dmv;
 326
 327         /* disk ioctls make sense only on block devices */
 328         if (minor(dev) == 0)
 329                 return ENOTTY;
 330
 331         switch(cmd) {
 332         case DIOCGPART:
 333                 if ((dmv = dev->si_drv1) == NULL)
 334                         return ENODEV;
 335                 if (dmv->diskp->d_info.d_media_blksize == 0) {
 336                         return ENOTSUP;
 337                 } else {
 338                         u_int64_t size;
 339                         struct partinfo *dpart = data;
 340                         bzero(dpart, sizeof(*dpart));
 341
 342                         size = dm_table_size(&dmv->table_head);
 343                         dpart->media_offset  = 0;
 344                         dpart->media_size    = size * DEV_BSIZE;
 345                         dpart->media_blocks  = size;
 346                         dpart->media_blksize = DEV_BSIZE;
 347                         dpart->fstype = FS_BSDFFS;
 348                 }
 349                 break;
 350
 351         default:
 352                 aprint_debug("unknown disk_ioctl called\n");
 353                 return ENOTTY;
 354                 break; /* NOT REACHED */
 355         }
 356
 357         return 0;
 358 }
 359
 360 /*
 361  * Do all IO operations on dm logical devices.
 362  */
 363 static int
 364 dmstrategy(struct dev_strategy_args *ap)
 365 {
 366         cdev_t dev = ap->a_head.a_dev;
 367         struct bio *bio = ap->a_bio;
 368         struct buf *bp = bio->bio_buf;
 369         int bypass;
 370
 371         dm_dev_t *dmv;
 372         dm_table_t  *tbl;
 373         dm_table_entry_t *table_en;
 374         struct buf *nestbuf;
 375
 376         uint64_t buf_start, buf_len, issued_len;
 377         uint64_t table_start, table_end;
 378         uint64_t start, end;
 379
 380         buf_start = bio->bio_offset;
 381         buf_len = bp->b_bcount;
 382
 383         tbl = NULL;
 384
 385         table_end = 0;
 386         issued_len = 0;
 387
 388         dmv = dev->si_drv1;
 389
 390         switch(bp->b_cmd) {
 391         case BUF_CMD_READ:
 392         case BUF_CMD_WRITE:
 393         case BUF_CMD_FREEBLKS:
 394                 bypass = 0;
 395                 break;
 396         case BUF_CMD_FLUSH:
 397                 bypass = 1;
 398                 KKASSERT(buf_len == 0);
 399                 break;
 400         default:
 401                 bp->b_error = EIO;
 402                 bp->b_resid = bp->b_bcount;
 403                 biodone(bio);
 404                 return 0;
 405         }
 406
 407         if (bypass == 0 &&
 408             bounds_check_with_mediasize(bio, DEV_BSIZE,
 409                                         dm_table_size(&dmv->table_head)) <= 0) {
 410                 bp->b_resid = bp->b_bcount;
 411                 biodone(bio);
 412                 return 0;
 413         }
 414
 415         /* Select active table */
 416         tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
 417
 418         nestiobuf_init(bio);
 419         devstat_start_transaction(&dmv->stats);
 420
 421         /*
 422          * Find out what tables I want to select.
 423          */
 424         SLIST_FOREACH(table_en, tbl, next) {
 425                 /*
 426                  * I need need number of bytes not blocks.
 427                  */
 428                 table_start = table_en->start * DEV_BSIZE;
 429                 table_end = table_start + (table_en->length) * DEV_BSIZE;
 430
 431                 /*
 432                  * Calculate the start and end
 433                  */
 434                 start = MAX(table_start, buf_start);
 435                 end = MIN(table_end, buf_start + buf_len);
 436
 437                 if (dm_debug_level) {
 438                         aprint_normal("----------------------------------------\n");
 439                         aprint_normal("table_start %010" PRIu64", table_end %010"
 440                             PRIu64 "\n", table_start, table_end);
 441                         aprint_normal("buf_start %010" PRIu64", buf_len %010"
 442                             PRIu64"\n", buf_start, buf_len);
 443                         aprint_normal("start-buf_start %010"PRIu64", end %010"
 444                             PRIu64"\n", start - buf_start, end);
 445                         aprint_normal("start %010" PRIu64", end %010"
 446                             PRIu64"\n", start, end);
 447                         aprint_normal("----------------------------------------\n");
 448                 }
 449
 450                 if (bypass) {
 451                         nestbuf = getpbuf(NULL);
 452                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 453
 454                         nestiobuf_add(bio, nestbuf, 0, 0, &dmv->stats);
 455                         nestbuf->b_bio1.bio_offset = 0;
 456                         table_en->target->strategy(table_en, nestbuf);
 457                 } else if (start < end) {
 458                         nestbuf = getpbuf(NULL);
 459                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 460
 461                         nestiobuf_add(bio, nestbuf,
 462                                       start - buf_start, (end - start),
 463                                       &dmv->stats);
 464                         issued_len += end - start;
 465
 466                         nestbuf->b_bio1.bio_offset = (start - table_start);
 467                         table_en->target->strategy(table_en, nestbuf);
 468                 }
 469         }
 470
 471         if (issued_len < buf_len)
 472                 nestiobuf_error(bio, EINVAL);
 473         nestiobuf_start(bio);
 474         dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
 475
 476         return 0;
 477 }
 478
 479 static int
 480 dmdump(struct dev_dump_args *ap)
 481 {
 482         cdev_t dev = ap->a_head.a_dev;
 483         dm_dev_t *dmv;
 484         dm_table_t  *tbl;
 485         dm_table_entry_t *table_en;
 486         uint64_t buf_start, buf_len, issued_len;
 487         uint64_t table_start, table_end;
 488         uint64_t start, end, data_offset;
 489         off_t offset;
 490         size_t length;
 491         int error = 0;
 492
 493         buf_start = ap->a_offset;
 494         buf_len = ap->a_length;
 495
 496         tbl = NULL;
 497
 498         table_end = 0;
 499         issued_len = 0;
 500
 501         dmv = dev->si_drv1;
 502
 503         /* Select active table */
 504         tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
 505
 506
 507         /*
 508          * Find out what tables I want to select.
 509          */
 510         SLIST_FOREACH(table_en, tbl, next) {
 511                 /*
 512                  * I need need number of bytes not blocks.
 513                  */
 514                 table_start = table_en->start * DEV_BSIZE;
 515                 table_end = table_start + (table_en->length) * DEV_BSIZE;
 516
 517                 /*
 518                  * Calculate the start and end
 519                  */
 520                 start = MAX(table_start, buf_start);
 521                 end = MIN(table_end, buf_start + buf_len);
 522
 523                 if (ap->a_length == 0) {
 524                         if (table_en->target->dump == NULL) {
 525                                 error = ENXIO;
 526                                 goto out;
 527                         }
 528
 529                         table_en->target->dump(table_en, NULL, 0, 0);
 530                 } else if (start < end) {
 531                         data_offset = start - buf_start;
 532                         offset = start - table_start;
 533                         length = end - start;
 534
 535                         if (table_en->target->dump == NULL) {
 536                                 error = ENXIO;
 537                                 goto out;
 538                         }
 539
 540                         table_en->target->dump(table_en,
 541                             (char *)ap->a_virtual + data_offset,
 542                             length, offset);
 543
 544                         issued_len += end - start;
 545                 }
 546         }
 547
 548         if (issued_len < buf_len)
 549                 error = EINVAL;
 550
 551 out:
 552         dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
 553
 554         return error;
 555 }
 556
 557 static int
 558 dmsize(struct dev_psize_args *ap)
 559 {
 560         cdev_t dev = ap->a_head.a_dev;
 561         dm_dev_t *dmv;
 562         uint64_t size;
 563
 564         size = 0;
 565
 566         if ((dmv = dev->si_drv1) == NULL)
 567                 return ENXIO;
 568
 569         size = dm_table_size(&dmv->table_head);
 570         ap->a_result = (int64_t)size;
 571
 572         return 0;
 573 }
 574
 575 #if 0
 576 static void
 577 dmminphys(struct buf *bp)
 578 {
 579
 580         bp->b_bcount = MIN(bp->b_bcount, MAXPHYS);
 581 }
 582 #endif
 583
 584 void
 585 dmsetdiskinfo(struct disk *disk, dm_table_head_t *head)
 586 {
 587         struct disk_info info;
 588         uint64_t dmp_size;
 589
 590         dmp_size = dm_table_size(head);
 591
 592         bzero(&info, sizeof(struct disk_info));
 593         info.d_media_blksize = DEV_BSIZE;
 594         info.d_media_blocks = dmp_size;
 595 #if 0
 596         /* this is set by disk_setdiskinfo */
 597         info.d_media_size = dmp_size * DEV_BSIZE;
 598 #endif
 599         info.d_dsflags = DSO_MBRQUIET | DSO_DEVICEMAPPER | DSO_RAWPSIZE;
 600
 601         info.d_secpertrack = 32;
 602         info.d_nheads = 64;
 603         info.d_secpercyl = info.d_secpertrack * info.d_nheads;
 604         info.d_ncylinders = dmp_size / info.d_secpercyl;
 605
 606         disk_setdiskinfo(disk, &info);
 607 }
 608
 609 /*
 610  * Transform char s to uint64_t offset number.
 611  */
 612 uint64_t
 613 atoi64(const char *s)
 614 {
 615         uint64_t n;
 616         n = 0;
 617
 618         while (*s != '\0') {
 619                 if (!isdigit(*s))
 620                         break;
 621
 622                 n = (10 * n) + (*s - '0');
 623                 s++;
 624         }
 625
 626         return n;
 627 }
 628
 629 void
 630 dm_builtin_init(void *arg)
 631 {
 632         modeventhand_t evh = (modeventhand_t)arg;
 633
 634         KKASSERT(evh != NULL);
 635         evh(NULL, MOD_LOAD, NULL);
 636 }
 637
 638 void
 639 dm_builtin_uninit(void *arg)
 640 {
 641         modeventhand_t evh = (modeventhand_t)arg;
 642
 643         KKASSERT(evh != NULL);
 644         evh(NULL, MOD_UNLOAD, NULL);
 645 }
 646
 647 TUNABLE_INT("debug.dm_debug", &dm_debug_level);
 648 SYSCTL_INT(_debug, OID_AUTO, dm_debug, CTLFLAG_RW, &dm_debug_level,
 649                0, "Enable device mapper debugging");
 650