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
 307         case NETBSD_DM_IOCTL:
 308                 aprint_debug("dm NETBSD_DM_IOCTL called\n");
 309                 break;
 310         default:
 311                 aprint_debug("dm unknown ioctl called\n");
 312                 return ENOTTY;
 313                 break; /* NOT REACHED */
 314         }
 315
 316         return 0;
 317 }
 318
 319  /*
 320   * Check for disk specific ioctls.
 321   */
 322
 323 static int
 324 disk_ioctl_switch(cdev_t dev, u_long cmd, void *data)
 325 {
 326         dm_dev_t *dmv;
 327
 328         /* disk ioctls make sense only on block devices */
 329         if (minor(dev) == 0)
 330                 return ENOTTY;
 331
 332         switch(cmd) {
 333         case DIOCGPART:
 334         {
 335                 struct partinfo *dpart;
 336                 u_int64_t size;
 337                 dpart = data;
 338                 bzero(dpart, sizeof(*dpart));
 339
 340                 if ((dmv = dev->si_drv1) == NULL)
 341                         return ENODEV;
 342                 if (dmv->diskp->d_info.d_media_blksize == 0) {
 343                         return ENOTSUP;
 344                 } else {
 345                         size = dm_table_size(&dmv->table_head);
 346                         dpart->media_offset  = 0;
 347                         dpart->media_size    = size * DEV_BSIZE;
 348                         dpart->media_blocks  = size;
 349                         dpart->media_blksize = DEV_BSIZE;
 350                         dpart->fstype = FS_BSDFFS;
 351                 }
 352                 break;
 353         }
 354
 355         default:
 356                 aprint_debug("unknown disk_ioctl called\n");
 357                 return ENOTTY;
 358                 break; /* NOT REACHED */
 359         }
 360
 361         return 0;
 362 }
 363
 364 /*
 365  * Do all IO operations on dm logical devices.
 366  */
 367 static int
 368 dmstrategy(struct dev_strategy_args *ap)
 369 {
 370         cdev_t dev = ap->a_head.a_dev;
 371         struct bio *bio = ap->a_bio;
 372         struct buf *bp = bio->bio_buf;
 373         int bypass;
 374
 375         dm_dev_t *dmv;
 376         dm_table_t  *tbl;
 377         dm_table_entry_t *table_en;
 378         struct buf *nestbuf;
 379
 380         uint64_t buf_start, buf_len, issued_len;
 381         uint64_t table_start, table_end;
 382         uint64_t start, end;
 383
 384         buf_start = bio->bio_offset;
 385         buf_len = bp->b_bcount;
 386
 387         tbl = NULL;
 388
 389         table_end = 0;
 390         issued_len = 0;
 391
 392         dmv = dev->si_drv1;
 393
 394         switch(bp->b_cmd) {
 395         case BUF_CMD_READ:
 396         case BUF_CMD_WRITE:
 397         case BUF_CMD_FREEBLKS:
 398                 bypass = 0;
 399                 break;
 400         case BUF_CMD_FLUSH:
 401                 bypass = 1;
 402                 KKASSERT(buf_len == 0);
 403                 break;
 404         default:
 405                 bp->b_error = EIO;
 406                 bp->b_resid = bp->b_bcount;
 407                 biodone(bio);
 408                 return 0;
 409         }
 410
 411         if (bypass == 0 &&
 412             bounds_check_with_mediasize(bio, DEV_BSIZE,
 413                                         dm_table_size(&dmv->table_head)) <= 0) {
 414                 bp->b_resid = bp->b_bcount;
 415                 biodone(bio);
 416                 return 0;
 417         }
 418
 419         /* Select active table */
 420         tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
 421
 422         nestiobuf_init(bio);
 423         devstat_start_transaction(&dmv->stats);
 424
 425         /*
 426          * Find out what tables I want to select.
 427          */
 428         SLIST_FOREACH(table_en, tbl, next) {
 429                 /*
 430                  * I need need number of bytes not blocks.
 431                  */
 432                 table_start = table_en->start * DEV_BSIZE;
 433                 table_end = table_start + (table_en->length) * DEV_BSIZE;
 434
 435                 /*
 436                  * Calculate the start and end
 437                  */
 438                 start = MAX(table_start, buf_start);
 439                 end = MIN(table_end, buf_start + buf_len);
 440
 441                 if (dm_debug_level) {
 442                         aprint_normal("----------------------------------------\n");
 443                         aprint_normal("table_start %010" PRIu64", table_end %010"
 444                             PRIu64 "\n", table_start, table_end);
 445                         aprint_normal("buf_start %010" PRIu64", buf_len %010"
 446                             PRIu64"\n", buf_start, buf_len);
 447                         aprint_normal("start-buf_start %010"PRIu64", end %010"
 448                             PRIu64"\n", start - buf_start, end);
 449                         aprint_normal("start %010" PRIu64", end %010"
 450                             PRIu64"\n", start, end);
 451                         aprint_normal("----------------------------------------\n");
 452                 }
 453
 454                 if (bypass) {
 455                         nestbuf = getpbuf(NULL);
 456                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 457
 458                         nestiobuf_add(bio, nestbuf, 0, 0, &dmv->stats);
 459                         nestbuf->b_bio1.bio_offset = 0;
 460                         table_en->target->strategy(table_en, nestbuf);
 461                 } else if (start < end) {
 462                         nestbuf = getpbuf(NULL);
 463                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 464
 465                         nestiobuf_add(bio, nestbuf,
 466                                       start - buf_start, (end - start),
 467                                       &dmv->stats);
 468                         issued_len += end - start;
 469
 470                         nestbuf->b_bio1.bio_offset = (start - table_start);
 471                         table_en->target->strategy(table_en, nestbuf);
 472                 }
 473         }
 474
 475         if (issued_len < buf_len)
 476                 nestiobuf_error(bio, EINVAL);
 477         nestiobuf_start(bio);
 478         dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
 479
 480         return 0;
 481 }
 482
 483 static int
 484 dmdump(struct dev_dump_args *ap)
 485 {
 486         cdev_t dev = ap->a_head.a_dev;
 487         dm_dev_t *dmv;
 488         dm_table_t  *tbl;
 489         dm_table_entry_t *table_en;
 490         uint64_t buf_start, buf_len, issued_len;
 491         uint64_t table_start, table_end;
 492         uint64_t start, end, data_offset;
 493         off_t offset;
 494         size_t length;
 495         int error = 0;
 496
 497         buf_start = ap->a_offset;
 498         buf_len = ap->a_length;
 499
 500         tbl = NULL;
 501
 502         table_end = 0;
 503         issued_len = 0;
 504
 505         dmv = dev->si_drv1;
 506
 507         /* Select active table */
 508         tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
 509
 510
 511         /*
 512          * Find out what tables I want to select.
 513          */
 514         SLIST_FOREACH(table_en, tbl, next) {
 515                 /*
 516                  * I need need number of bytes not blocks.
 517                  */
 518                 table_start = table_en->start * DEV_BSIZE;
 519                 table_end = table_start + (table_en->length) * DEV_BSIZE;
 520
 521                 /*
 522                  * Calculate the start and end
 523                  */
 524                 start = MAX(table_start, buf_start);
 525                 end = MIN(table_end, buf_start + buf_len);
 526
 527                 if (ap->a_length == 0) {
 528                         if (table_en->target->dump == NULL) {
 529                                 error = ENXIO;
 530                                 goto out;
 531                         }
 532
 533                         table_en->target->dump(table_en, NULL, 0, 0);
 534                 } else if (start < end) {
 535                         data_offset = start - buf_start;
 536                         offset = start - table_start;
 537                         length = end - start;
 538
 539                         if (table_en->target->dump == NULL) {
 540                                 error = ENXIO;
 541                                 goto out;
 542                         }
 543
 544                         table_en->target->dump(table_en,
 545                             (char *)ap->a_virtual + data_offset,
 546                             length, offset);
 547
 548                         issued_len += end - start;
 549                 }
 550         }
 551
 552         if (issued_len < buf_len)
 553                 error = EINVAL;
 554
 555 out:
 556         dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
 557
 558         return error;
 559 }
 560
 561 static int
 562 dmsize(struct dev_psize_args *ap)
 563 {
 564         cdev_t dev = ap->a_head.a_dev;
 565         dm_dev_t *dmv;
 566         uint64_t size;
 567
 568         size = 0;
 569
 570         if ((dmv = dev->si_drv1) == NULL)
 571                 return ENXIO;
 572
 573         size = dm_table_size(&dmv->table_head);
 574         ap->a_result = (int64_t)size;
 575
 576         return 0;
 577 }
 578
 579 #if 0
 580 static void
 581 dmminphys(struct buf *bp)
 582 {
 583
 584         bp->b_bcount = MIN(bp->b_bcount, MAXPHYS);
 585 }
 586 #endif
 587
 588 void
 589 dmsetdiskinfo(struct disk *disk, dm_table_head_t *head)
 590 {
 591         struct disk_info info;
 592         uint64_t dmp_size;
 593
 594         dmp_size = dm_table_size(head);
 595
 596         bzero(&info, sizeof(struct disk_info));
 597         info.d_media_blksize = DEV_BSIZE;
 598         info.d_media_blocks = dmp_size;
 599 #if 0
 600         /* this is set by disk_setdiskinfo */
 601         info.d_media_size = dmp_size * DEV_BSIZE;
 602 #endif
 603         info.d_dsflags = DSO_MBRQUIET | DSO_DEVICEMAPPER | DSO_RAWPSIZE;
 604
 605         info.d_secpertrack = 32;
 606         info.d_nheads = 64;
 607         info.d_secpercyl = info.d_secpertrack * info.d_nheads;
 608         info.d_ncylinders = dmp_size / info.d_secpercyl;
 609
 610         disk_setdiskinfo(disk, &info);
 611 }
 612
 613 /*
 614  * Transform char s to uint64_t offset number.
 615  */
 616 uint64_t
 617 atoi64(const char *s)
 618 {
 619         uint64_t n;
 620         n = 0;
 621
 622         while (*s != '\0') {
 623                 if (!isdigit(*s))
 624                         break;
 625
 626                 n = (10 * n) + (*s - '0');
 627                 s++;
 628         }
 629
 630         return n;
 631 }
 632
 633 void
 634 dm_builtin_init(void *arg)
 635 {
 636         modeventhand_t evh = (modeventhand_t)arg;
 637
 638         KKASSERT(evh != NULL);
 639         evh(NULL, MOD_LOAD, NULL);
 640 }
 641
 642 void
 643 dm_builtin_uninit(void *arg)
 644 {
 645         modeventhand_t evh = (modeventhand_t)arg;
 646
 647         KKASSERT(evh != NULL);
 648         evh(NULL, MOD_UNLOAD, NULL);
 649 }
 650
 651 TUNABLE_INT("debug.dm_debug", &dm_debug_level);
 652 SYSCTL_INT(_debug, OID_AUTO, dm_debug, CTLFLAG_RW, &dm_debug_level,
 653                0, "Enable device mapper debugging");
 654