1 /*- 2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org> 3 * Copyright (c) 2012 Andrey V. Elsukov <ae@FreeBSD.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 /* 32 * BIOS disk device handling. 33 * 34 * Ideas and algorithms from: 35 * 36 * - NetBSD libi386/biosdisk.c 37 * - FreeBSD biosboot/disk.c 38 * 39 */ 40 41 #include <sys/disk.h> 42 #include <sys/limits.h> 43 #include <sys/queue.h> 44 #include <stand.h> 45 #include <machine/bootinfo.h> 46 #include <stdarg.h> 47 #include <stdbool.h> 48 49 #include <bootstrap.h> 50 #include <btxv86.h> 51 #include <edd.h> 52 #include "disk.h" 53 #include "libi386.h" 54 55 #define BIOS_NUMDRIVES 0x475 56 #define BIOSDISK_SECSIZE 512 57 #define BUFSIZE (1 * BIOSDISK_SECSIZE) 58 59 #define DT_ATAPI 0x10 /* disk type for ATAPI floppies */ 60 #define WDMAJOR 0 /* major numbers for devices we frontend for */ 61 #define WFDMAJOR 1 62 #define FDMAJOR 2 63 #define DAMAJOR 4 64 #define ACDMAJOR 117 65 #define CDMAJOR 15 66 67 /* 68 * INT13 commands 69 */ 70 #define CMD_RESET 0x0000 71 #define CMD_READ_CHS 0x0200 72 #define CMD_WRITE_CHS 0x0300 73 #define CMD_READ_PARAM 0x0800 74 #define CMD_DRIVE_TYPE 0x1500 75 #define CMD_CHECK_EDD 0x4100 76 #define CMD_READ_LBA 0x4200 77 #define CMD_WRITE_LBA 0x4300 78 #define CMD_EXT_PARAM 0x4800 79 #define CMD_CD_GET_STATUS 0x4b01 80 81 #define DISK_BIOS 0x13 82 83 #ifdef DISK_DEBUG 84 #define DPRINTF(fmt, args...) printf("%s: " fmt "\n", __func__, ## args) 85 #else 86 #define DPRINTF(fmt, args...) ((void)0) 87 #endif 88 89 struct specification_packet { 90 uint8_t sp_size; 91 uint8_t sp_bootmedia; 92 uint8_t sp_drive; 93 uint8_t sp_controller; 94 uint32_t sp_lba; 95 uint16_t sp_devicespec; 96 uint16_t sp_buffersegment; 97 uint16_t sp_loadsegment; 98 uint16_t sp_sectorcount; 99 uint16_t sp_cylsec; 100 uint8_t sp_head; 101 uint8_t sp_dummy[16]; /* Avoid memory corruption */ 102 }; 103 104 /* 105 * List of BIOS devices, translation from disk unit number to 106 * BIOS unit number. 107 */ 108 typedef struct bdinfo 109 { 110 STAILQ_ENTRY(bdinfo) bd_link; /* link in device list */ 111 int bd_unit; /* BIOS unit number */ 112 int bd_cyl; /* BIOS geometry */ 113 int bd_hds; 114 int bd_sec; 115 int bd_flags; 116 #define BD_MODEINT13 0x0000 117 #define BD_MODEEDD1 0x0001 118 #define BD_MODEEDD3 0x0002 119 #define BD_MODEEDD (BD_MODEEDD1 | BD_MODEEDD3) 120 #define BD_MODEMASK 0x0003 121 #define BD_FLOPPY 0x0004 122 #define BD_CDROM 0x0008 123 #define BD_NO_MEDIA 0x0010 124 int bd_type; /* BIOS 'drive type' (floppy only) */ 125 uint16_t bd_sectorsize; /* Sector size */ 126 uint64_t bd_sectors; /* Disk size */ 127 int bd_open; /* reference counter */ 128 void *bd_bcache; /* buffer cache data */ 129 } bdinfo_t; 130 131 #define BD_RD 0 132 #define BD_WR 1 133 134 typedef STAILQ_HEAD(bdinfo_list, bdinfo) bdinfo_list_t; 135 static bdinfo_list_t fdinfo = STAILQ_HEAD_INITIALIZER(fdinfo); 136 static bdinfo_list_t cdinfo = STAILQ_HEAD_INITIALIZER(cdinfo); 137 static bdinfo_list_t hdinfo = STAILQ_HEAD_INITIALIZER(hdinfo); 138 139 static void bd_io_workaround(bdinfo_t *); 140 static int bd_io(struct disk_devdesc *, bdinfo_t *, daddr_t, int, caddr_t, int); 141 static bool bd_int13probe(bdinfo_t *); 142 143 static int bd_init(void); 144 static int cd_init(void); 145 static int fd_init(void); 146 static int bd_strategy(void *devdata, int flag, daddr_t dblk, size_t size, 147 char *buf, size_t *rsize); 148 static int bd_realstrategy(void *devdata, int flag, daddr_t dblk, size_t size, 149 char *buf, size_t *rsize); 150 static int bd_open(struct open_file *f, ...); 151 static int bd_close(struct open_file *f); 152 static int bd_ioctl(struct open_file *f, u_long cmd, void *data); 153 static int bd_print(int verbose); 154 static int cd_print(int verbose); 155 static int fd_print(int verbose); 156 static void bd_reset_disk(int); 157 static int bd_get_diskinfo_std(struct bdinfo *); 158 159 struct devsw biosfd = { 160 .dv_name = "fd", 161 .dv_type = DEVT_FD, 162 .dv_init = fd_init, 163 .dv_strategy = bd_strategy, 164 .dv_open = bd_open, 165 .dv_close = bd_close, 166 .dv_ioctl = bd_ioctl, 167 .dv_print = fd_print, 168 .dv_cleanup = nullsys, 169 }; 170 171 struct devsw bioscd = { 172 .dv_name = "cd", 173 .dv_type = DEVT_CD, 174 .dv_init = cd_init, 175 .dv_strategy = bd_strategy, 176 .dv_open = bd_open, 177 .dv_close = bd_close, 178 .dv_ioctl = bd_ioctl, 179 .dv_print = cd_print, 180 .dv_cleanup = nullsys, 181 }; 182 183 struct devsw bioshd = { 184 .dv_name = "disk", 185 .dv_type = DEVT_DISK, 186 .dv_init = bd_init, 187 .dv_strategy = bd_strategy, 188 .dv_open = bd_open, 189 .dv_close = bd_close, 190 .dv_ioctl = bd_ioctl, 191 .dv_print = bd_print, 192 .dv_cleanup = nullsys, 193 .dv_fmtdev = disk_fmtdev, 194 }; 195 196 static bdinfo_list_t * 197 bd_get_bdinfo_list(struct devsw *dev) 198 { 199 if (dev->dv_type == DEVT_DISK) 200 return (&hdinfo); 201 if (dev->dv_type == DEVT_CD) 202 return (&cdinfo); 203 if (dev->dv_type == DEVT_FD) 204 return (&fdinfo); 205 return (NULL); 206 } 207 208 /* XXX this gets called way way too often, investigate */ 209 static bdinfo_t * 210 bd_get_bdinfo(struct devdesc *dev) 211 { 212 bdinfo_list_t *bdi; 213 bdinfo_t *bd = NULL; 214 int unit; 215 216 bdi = bd_get_bdinfo_list(dev->d_dev); 217 if (bdi == NULL) 218 return (bd); 219 220 unit = 0; 221 STAILQ_FOREACH(bd, bdi, bd_link) { 222 if (unit == dev->d_unit) 223 return (bd); 224 unit++; 225 } 226 return (bd); 227 } 228 229 /* 230 * Translate between BIOS device numbers and our private unit numbers. 231 */ 232 int 233 bd_bios2unit(int biosdev) 234 { 235 bdinfo_list_t *bdi[] = { &fdinfo, &cdinfo, &hdinfo, NULL }; 236 bdinfo_t *bd; 237 int i, unit; 238 239 DPRINTF("looking for bios device 0x%x", biosdev); 240 for (i = 0; bdi[i] != NULL; i++) { 241 unit = 0; 242 STAILQ_FOREACH(bd, bdi[i], bd_link) { 243 if (bd->bd_unit == biosdev) { 244 DPRINTF("bd unit %d is BIOS device 0x%x", unit, 245 bd->bd_unit); 246 return (unit); 247 } 248 unit++; 249 } 250 } 251 return (-1); 252 } 253 254 int 255 bd_unit2bios(struct i386_devdesc *dev) 256 { 257 bdinfo_list_t *bdi; 258 bdinfo_t *bd; 259 int unit; 260 261 bdi = bd_get_bdinfo_list(dev->dd.d_dev); 262 if (bdi == NULL) 263 return (-1); 264 265 unit = 0; 266 STAILQ_FOREACH(bd, bdi, bd_link) { 267 if (unit == dev->dd.d_unit) 268 return (bd->bd_unit); 269 unit++; 270 } 271 return (-1); 272 } 273 274 /* 275 * Use INT13 AH=15 - Read Drive Type. 276 */ 277 static int 278 fd_count(void) 279 { 280 int drive; 281 282 for (drive = 0; drive < MAXBDDEV; drive++) { 283 bd_reset_disk(drive); 284 285 v86.ctl = V86_FLAGS; 286 v86.addr = DISK_BIOS; 287 v86.eax = CMD_DRIVE_TYPE; 288 v86.edx = drive; 289 v86int(); 290 291 if (V86_CY(v86.efl)) 292 break; 293 294 if ((v86.eax & 0x300) == 0) 295 break; 296 } 297 298 return (drive); 299 } 300 301 /* 302 * Quiz the BIOS for disk devices, save a little info about them. 303 */ 304 static int 305 fd_init(void) 306 { 307 int unit, numfd; 308 bdinfo_t *bd; 309 310 numfd = fd_count(); 311 for (unit = 0; unit < numfd; unit++) { 312 if ((bd = calloc(1, sizeof(*bd))) == NULL) 313 break; 314 315 bd->bd_sectorsize = BIOSDISK_SECSIZE; 316 bd->bd_flags = BD_FLOPPY; 317 bd->bd_unit = unit; 318 319 /* Use std diskinfo for floppy drive */ 320 if (bd_get_diskinfo_std(bd) != 0) { 321 free(bd); 322 break; 323 } 324 if (bd->bd_sectors == 0) 325 bd->bd_flags |= BD_NO_MEDIA; 326 327 printf("BIOS drive %c: is %s%d\n", ('A' + unit), 328 biosfd.dv_name, unit); 329 330 STAILQ_INSERT_TAIL(&fdinfo, bd, bd_link); 331 } 332 333 bcache_add_dev(unit); 334 return (0); 335 } 336 337 static int 338 bd_init(void) 339 { 340 int base, unit; 341 bdinfo_t *bd; 342 343 TSENTER(); 344 345 base = 0x80; 346 for (unit = 0; unit < *(unsigned char *)PTOV(BIOS_NUMDRIVES); unit++) { 347 /* 348 * Check the BIOS equipment list for number of fixed disks. 349 */ 350 if ((bd = calloc(1, sizeof(*bd))) == NULL) 351 break; 352 bd->bd_unit = base + unit; 353 if (!bd_int13probe(bd)) { 354 free(bd); 355 break; 356 } 357 358 printf("BIOS drive %c: is %s%d\n", ('C' + unit), 359 bioshd.dv_name, unit); 360 361 STAILQ_INSERT_TAIL(&hdinfo, bd, bd_link); 362 } 363 bcache_add_dev(unit); 364 TSEXIT(); 365 return (0); 366 } 367 368 /* 369 * We can't quiz, we have to be told what device to use, so this function 370 * doesn't do anything. Instead, the loader calls bc_add() with the BIOS 371 * device number to add. 372 */ 373 static int 374 cd_init(void) 375 { 376 377 return (0); 378 } 379 380 /* 381 * Information from bootable CD-ROM. 382 */ 383 static int 384 bd_get_diskinfo_cd(struct bdinfo *bd) 385 { 386 struct specification_packet bc_sp; 387 int ret = -1; 388 389 (void) memset(&bc_sp, 0, sizeof (bc_sp)); 390 /* Set sp_size as per specification. */ 391 bc_sp.sp_size = sizeof (bc_sp) - sizeof (bc_sp.sp_dummy); 392 393 v86.ctl = V86_FLAGS; 394 v86.addr = DISK_BIOS; 395 v86.eax = CMD_CD_GET_STATUS; 396 v86.edx = bd->bd_unit; 397 v86.ds = VTOPSEG(&bc_sp); 398 v86.esi = VTOPOFF(&bc_sp); 399 v86int(); 400 401 if ((v86.eax & 0xff00) == 0 && 402 bc_sp.sp_drive == bd->bd_unit) { 403 bd->bd_cyl = ((bc_sp.sp_cylsec & 0xc0) << 2) + 404 ((bc_sp.sp_cylsec & 0xff00) >> 8) + 1; 405 bd->bd_sec = bc_sp.sp_cylsec & 0x3f; 406 bd->bd_hds = bc_sp.sp_head + 1; 407 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 408 409 if (bc_sp.sp_bootmedia & 0x0F) { 410 /* Floppy or hard-disk emulation */ 411 bd->bd_sectorsize = BIOSDISK_SECSIZE; 412 return (-1); 413 } else { 414 bd->bd_sectorsize = 2048; 415 bd->bd_flags = BD_MODEEDD | BD_CDROM; 416 ret = 0; 417 } 418 } 419 420 /* 421 * If this is the boot_drive, default to non-emulation bootable CD-ROM. 422 */ 423 if (ret != 0 && bd->bd_unit >= 0x88) { 424 bd->bd_cyl = 0; 425 bd->bd_hds = 1; 426 bd->bd_sec = 15; 427 bd->bd_sectorsize = 2048; 428 bd->bd_flags = BD_MODEEDD | BD_CDROM; 429 bd->bd_sectors = 0; 430 ret = 0; 431 } 432 433 /* 434 * Note we can not use bd_get_diskinfo_ext() nor bd_get_diskinfo_std() 435 * here - some systems do get hung with those. 436 */ 437 /* 438 * Still no size? use 7.961GB. The size does not really matter 439 * as long as it is reasonably large to make our reads to pass 440 * the sector count check. 441 */ 442 if (bd->bd_sectors == 0) 443 bd->bd_sectors = 4173824; 444 445 return (ret); 446 } 447 448 int 449 bc_add(int biosdev) 450 { 451 bdinfo_t *bd; 452 int nbcinfo = 0; 453 454 if (!STAILQ_EMPTY(&cdinfo)) 455 return (-1); 456 457 if ((bd = calloc(1, sizeof(*bd))) == NULL) 458 return (-1); 459 460 bd->bd_unit = biosdev; 461 if (bd_get_diskinfo_cd(bd) < 0) { 462 free(bd); 463 return (-1); 464 } 465 466 STAILQ_INSERT_TAIL(&cdinfo, bd, bd_link); 467 printf("BIOS CD is cd%d\n", nbcinfo); 468 nbcinfo++; 469 bcache_add_dev(nbcinfo); /* register cd device in bcache */ 470 return(0); 471 } 472 473 /* 474 * Return EDD version or 0 if EDD is not supported on this drive. 475 */ 476 static int 477 bd_check_extensions(int unit) 478 { 479 /* do not use ext calls for floppy devices */ 480 if (unit < 0x80) 481 return (0); 482 483 /* Determine if we can use EDD with this device. */ 484 v86.ctl = V86_FLAGS; 485 v86.addr = DISK_BIOS; 486 v86.eax = CMD_CHECK_EDD; 487 v86.edx = unit; 488 v86.ebx = EDD_QUERY_MAGIC; 489 v86int(); 490 491 if (V86_CY(v86.efl) || /* carry set */ 492 (v86.ebx & 0xffff) != EDD_INSTALLED) /* signature */ 493 return (0); 494 495 /* extended disk access functions (AH=42h-44h,47h,48h) supported */ 496 if ((v86.ecx & EDD_INTERFACE_FIXED_DISK) == 0) 497 return (0); 498 499 return ((v86.eax >> 8) & 0xff); 500 } 501 502 static void 503 bd_reset_disk(int unit) 504 { 505 /* reset disk */ 506 v86.ctl = V86_FLAGS; 507 v86.addr = DISK_BIOS; 508 v86.eax = CMD_RESET; 509 v86.edx = unit; 510 v86int(); 511 } 512 513 /* 514 * Read CHS info. Return 0 on success, error otherwise. 515 */ 516 static int 517 bd_get_diskinfo_std(struct bdinfo *bd) 518 { 519 bzero(&v86, sizeof(v86)); 520 v86.ctl = V86_FLAGS; 521 v86.addr = DISK_BIOS; 522 v86.eax = CMD_READ_PARAM; 523 v86.edx = bd->bd_unit; 524 v86int(); 525 526 if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0)) 527 return ((v86.eax & 0xff00) >> 8); 528 529 /* return custom error on absurd sector number */ 530 if ((v86.ecx & 0x3f) == 0) 531 return (0x60); 532 533 bd->bd_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1; 534 /* Convert max head # -> # of heads */ 535 bd->bd_hds = ((v86.edx & 0xff00) >> 8) + 1; 536 bd->bd_sec = v86.ecx & 0x3f; 537 bd->bd_type = v86.ebx; 538 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 539 540 return (0); 541 } 542 543 /* 544 * Read EDD info. Return 0 on success, error otherwise. 545 * 546 * Avoid stack corruption on some systems by adding extra bytes to 547 * params block. 548 */ 549 static int 550 bd_get_diskinfo_ext(struct bdinfo *bd) 551 { 552 struct disk_params { 553 struct edd_params head; 554 struct edd_device_path_v3 device_path; 555 uint8_t dummy[16]; 556 } __packed dparams; 557 struct edd_params *params; 558 uint64_t total; 559 560 params = &dparams.head; 561 562 /* Get disk params */ 563 bzero(&dparams, sizeof(dparams)); 564 params->len = sizeof(struct edd_params_v3); 565 v86.ctl = V86_FLAGS; 566 v86.addr = DISK_BIOS; 567 v86.eax = CMD_EXT_PARAM; 568 v86.edx = bd->bd_unit; 569 v86.ds = VTOPSEG(&dparams); 570 v86.esi = VTOPOFF(&dparams); 571 v86int(); 572 573 if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0)) 574 return ((v86.eax & 0xff00) >> 8); 575 576 /* 577 * Sector size must be a multiple of 512 bytes. 578 * An alternate test would be to check power of 2, 579 * powerof2(params.sector_size). 580 * 16K is largest read buffer we can use at this time. 581 */ 582 if (params->sector_size >= 512 && 583 params->sector_size <= 16384 && 584 (params->sector_size % BIOSDISK_SECSIZE) == 0) 585 bd->bd_sectorsize = params->sector_size; 586 587 bd->bd_cyl = params->cylinders; 588 bd->bd_hds = params->heads; 589 bd->bd_sec = params->sectors_per_track; 590 591 if (params->sectors != 0) { 592 total = params->sectors; 593 } else { 594 total = (uint64_t)params->cylinders * 595 params->heads * params->sectors_per_track; 596 } 597 bd->bd_sectors = total; 598 599 return (0); 600 } 601 602 /* 603 * Try to detect a device supported by the legacy int13 BIOS 604 */ 605 static bool 606 bd_int13probe(bdinfo_t *bd) 607 { 608 int edd, ret; 609 610 bd->bd_flags &= ~BD_NO_MEDIA; 611 612 if ((bd->bd_flags & BD_CDROM) != 0) { 613 return (bd_get_diskinfo_cd(bd) == 0); 614 } 615 616 edd = bd_check_extensions(bd->bd_unit); 617 if (edd == 0) 618 bd->bd_flags |= BD_MODEINT13; 619 else if (edd < 0x30) 620 bd->bd_flags |= BD_MODEEDD1; 621 else 622 bd->bd_flags |= BD_MODEEDD3; 623 624 /* Default sector size */ 625 if (bd->bd_sectorsize == 0) 626 bd->bd_sectorsize = BIOSDISK_SECSIZE; 627 628 /* 629 * Test if the floppy device is present, so we can avoid receiving 630 * bogus information from bd_get_diskinfo_std(). 631 */ 632 if (bd->bd_unit < 0x80) { 633 /* reset disk */ 634 bd_reset_disk(bd->bd_unit); 635 636 /* Get disk type */ 637 v86.ctl = V86_FLAGS; 638 v86.addr = DISK_BIOS; 639 v86.eax = CMD_DRIVE_TYPE; 640 v86.edx = bd->bd_unit; 641 v86int(); 642 if (V86_CY(v86.efl) || (v86.eax & 0x300) == 0) 643 return (false); 644 } 645 646 ret = 1; 647 if (edd != 0) 648 ret = bd_get_diskinfo_ext(bd); 649 if (ret != 0 || bd->bd_sectors == 0) 650 ret = bd_get_diskinfo_std(bd); 651 652 if (ret != 0 && bd->bd_unit < 0x80) { 653 /* Set defaults for 1.44 floppy */ 654 bd->bd_cyl = 80; 655 bd->bd_hds = 2; 656 bd->bd_sec = 18; 657 bd->bd_sectors = 2880; 658 /* Since we are there, there most likely is no media */ 659 bd->bd_flags |= BD_NO_MEDIA; 660 ret = 0; 661 } 662 663 if (ret != 0) { 664 if (bd->bd_sectors != 0 && edd != 0) { 665 bd->bd_sec = 63; 666 bd->bd_hds = 255; 667 bd->bd_cyl = 668 (bd->bd_sectors + bd->bd_sec * bd->bd_hds - 1) / 669 bd->bd_sec * bd->bd_hds; 670 } else { 671 const char *dv_name; 672 673 if ((bd->bd_flags & BD_FLOPPY) != 0) 674 dv_name = biosfd.dv_name; 675 else 676 dv_name = bioshd.dv_name; 677 678 printf("Can not get information about %s unit %#x\n", 679 dv_name, bd->bd_unit); 680 return (false); 681 } 682 } 683 684 if (bd->bd_sec == 0) 685 bd->bd_sec = 63; 686 if (bd->bd_hds == 0) 687 bd->bd_hds = 255; 688 689 if (bd->bd_sectors == 0) 690 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 691 692 DPRINTF("unit 0x%x geometry %d/%d/%d\n", bd->bd_unit, bd->bd_cyl, 693 bd->bd_hds, bd->bd_sec); 694 695 return (true); 696 } 697 698 static int 699 bd_count(bdinfo_list_t *bdi) 700 { 701 bdinfo_t *bd; 702 int i; 703 704 i = 0; 705 STAILQ_FOREACH(bd, bdi, bd_link) 706 i++; 707 return (i); 708 } 709 710 /* 711 * Print information about disks 712 */ 713 static int 714 bd_print_common(struct devsw *dev, bdinfo_list_t *bdi, int verbose) 715 { 716 char line[80]; 717 struct disk_devdesc devd; 718 bdinfo_t *bd; 719 int i, ret = 0; 720 char drive; 721 722 if (STAILQ_EMPTY(bdi)) 723 return (0); 724 725 printf("%s devices:", dev->dv_name); 726 if ((ret = pager_output("\n")) != 0) 727 return (ret); 728 729 i = -1; 730 STAILQ_FOREACH(bd, bdi, bd_link) { 731 i++; 732 733 switch (dev->dv_type) { 734 case DEVT_FD: 735 drive = 'A'; 736 break; 737 case DEVT_CD: 738 drive = 'C' + bd_count(&hdinfo); 739 break; 740 default: 741 drive = 'C'; 742 break; 743 } 744 745 snprintf(line, sizeof(line), 746 " %s%d: BIOS drive %c (%s%ju X %u):\n", 747 dev->dv_name, i, drive + i, 748 (bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA ? 749 "no media, " : "", 750 (uintmax_t)bd->bd_sectors, 751 bd->bd_sectorsize); 752 if ((ret = pager_output(line)) != 0) 753 break; 754 755 if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 756 continue; 757 758 if (dev->dv_type != DEVT_DISK) 759 continue; 760 761 devd.dd.d_dev = dev; 762 devd.dd.d_unit = i; 763 devd.d_slice = D_SLICENONE; 764 devd.d_partition = D_PARTNONE; 765 if (disk_open(&devd, 766 bd->bd_sectorsize * bd->bd_sectors, 767 bd->bd_sectorsize) == 0) { 768 snprintf(line, sizeof(line), " %s%d", 769 dev->dv_name, i); 770 ret = disk_print(&devd, line, verbose); 771 disk_close(&devd); 772 if (ret != 0) 773 break; 774 } 775 } 776 return (ret); 777 } 778 779 static int 780 fd_print(int verbose) 781 { 782 return (bd_print_common(&biosfd, &fdinfo, verbose)); 783 } 784 785 static int 786 bd_print(int verbose) 787 { 788 return (bd_print_common(&bioshd, &hdinfo, verbose)); 789 } 790 791 static int 792 cd_print(int verbose) 793 { 794 return (bd_print_common(&bioscd, &cdinfo, verbose)); 795 } 796 797 /* 798 * Read disk size from partition. 799 * This is needed to work around buggy BIOS systems returning 800 * wrong (truncated) disk media size. 801 * During bd_probe() we tested if the multiplication of bd_sectors 802 * would overflow so it should be safe to perform here. 803 */ 804 static uint64_t 805 bd_disk_get_sectors(struct disk_devdesc *dev) 806 { 807 bdinfo_t *bd; 808 struct disk_devdesc disk; 809 uint64_t size; 810 811 bd = bd_get_bdinfo(&dev->dd); 812 if (bd == NULL) 813 return (0); 814 815 disk.dd.d_dev = dev->dd.d_dev; 816 disk.dd.d_unit = dev->dd.d_unit; 817 disk.d_slice = D_SLICENONE; 818 disk.d_partition = D_PARTNONE; 819 disk.d_offset = 0; 820 821 size = bd->bd_sectors * bd->bd_sectorsize; 822 if (disk_open(&disk, size, bd->bd_sectorsize) == 0) { 823 (void) disk_ioctl(&disk, DIOCGMEDIASIZE, &size); 824 disk_close(&disk); 825 } 826 return (size / bd->bd_sectorsize); 827 } 828 829 /* 830 * Attempt to open the disk described by (dev) for use by (f). 831 * 832 * Note that the philosophy here is "give them exactly what 833 * they ask for". This is necessary because being too "smart" 834 * about what the user might want leads to complications. 835 * (eg. given no slice or partition value, with a disk that is 836 * sliced - are they after the first BSD slice, or the DOS 837 * slice before it?) 838 */ 839 static int 840 bd_open(struct open_file *f, ...) 841 { 842 bdinfo_t *bd; 843 struct disk_devdesc *dev; 844 va_list ap; 845 int rc; 846 847 TSENTER(); 848 849 va_start(ap, f); 850 dev = va_arg(ap, struct disk_devdesc *); 851 va_end(ap); 852 853 bd = bd_get_bdinfo(&dev->dd); 854 if (bd == NULL) 855 return (EIO); 856 857 if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) { 858 if (!bd_int13probe(bd)) 859 return (EIO); 860 if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 861 return (EIO); 862 } 863 if (bd->bd_bcache == NULL) 864 bd->bd_bcache = bcache_allocate(); 865 866 if (bd->bd_open == 0) 867 bd->bd_sectors = bd_disk_get_sectors(dev); 868 bd->bd_open++; 869 870 rc = 0; 871 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 872 rc = disk_open(dev, bd->bd_sectors * bd->bd_sectorsize, 873 bd->bd_sectorsize); 874 if (rc != 0) { 875 bd->bd_open--; 876 if (bd->bd_open == 0) { 877 bcache_free(bd->bd_bcache); 878 bd->bd_bcache = NULL; 879 } 880 } 881 } 882 TSEXIT(); 883 return (rc); 884 } 885 886 static int 887 bd_close(struct open_file *f) 888 { 889 struct disk_devdesc *dev; 890 bdinfo_t *bd; 891 int rc = 0; 892 893 dev = (struct disk_devdesc *)f->f_devdata; 894 bd = bd_get_bdinfo(&dev->dd); 895 if (bd == NULL) 896 return (EIO); 897 898 bd->bd_open--; 899 if (bd->bd_open == 0) { 900 bcache_free(bd->bd_bcache); 901 bd->bd_bcache = NULL; 902 } 903 if (dev->dd.d_dev->dv_type == DEVT_DISK) 904 rc = disk_close(dev); 905 return (rc); 906 } 907 908 static int 909 bd_ioctl(struct open_file *f, u_long cmd, void *data) 910 { 911 bdinfo_t *bd; 912 struct disk_devdesc *dev; 913 int rc; 914 915 dev = (struct disk_devdesc *)f->f_devdata; 916 bd = bd_get_bdinfo(&dev->dd); 917 if (bd == NULL) 918 return (EIO); 919 920 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 921 rc = disk_ioctl(dev, cmd, data); 922 if (rc != ENOTTY) 923 return (rc); 924 } 925 926 switch (cmd) { 927 case DIOCGSECTORSIZE: 928 *(uint32_t *)data = bd->bd_sectorsize; 929 break; 930 case DIOCGMEDIASIZE: 931 *(uint64_t *)data = bd->bd_sectors * bd->bd_sectorsize; 932 break; 933 default: 934 return (ENOTTY); 935 } 936 return (0); 937 } 938 939 static int 940 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, 941 char *buf, size_t *rsize) 942 { 943 bdinfo_t *bd; 944 struct bcache_devdata bcd; 945 struct disk_devdesc *dev; 946 daddr_t offset; 947 948 dev = (struct disk_devdesc *)devdata; 949 bd = bd_get_bdinfo(&dev->dd); 950 if (bd == NULL) 951 return (EINVAL); 952 953 bcd.dv_strategy = bd_realstrategy; 954 bcd.dv_devdata = devdata; 955 bcd.dv_cache = bd->bd_bcache; 956 957 offset = 0; 958 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 959 960 offset = dev->d_offset * bd->bd_sectorsize; 961 offset /= BIOSDISK_SECSIZE; 962 } 963 return (bcache_strategy(&bcd, rw, dblk + offset, size, 964 buf, rsize)); 965 } 966 967 static int 968 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, 969 char *buf, size_t *rsize) 970 { 971 struct disk_devdesc *dev = (struct disk_devdesc *)devdata; 972 bdinfo_t *bd; 973 uint64_t disk_blocks, offset, d_offset; 974 size_t blks, blkoff, bsize, bio_size, rest; 975 caddr_t bbuf = NULL; 976 int rc; 977 978 bd = bd_get_bdinfo(&dev->dd); 979 if (bd == NULL || (bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 980 return (EIO); 981 982 /* 983 * First make sure the IO size is a multiple of 512 bytes. While we do 984 * process partial reads below, the strategy mechanism is built 985 * assuming IO is a multiple of 512B blocks. If the request is not 986 * a multiple of 512B blocks, it has to be some sort of bug. 987 */ 988 if (size == 0 || (size % BIOSDISK_SECSIZE) != 0) { 989 printf("bd_strategy: %d bytes I/O not multiple of %d\n", 990 size, BIOSDISK_SECSIZE); 991 return (EIO); 992 } 993 994 DPRINTF("open_disk %p", dev); 995 996 offset = dblk * BIOSDISK_SECSIZE; 997 dblk = offset / bd->bd_sectorsize; 998 blkoff = offset % bd->bd_sectorsize; 999 1000 /* 1001 * Check the value of the size argument. We do have quite small 1002 * heap (64MB), but we do not know good upper limit, so we check against 1003 * INT_MAX here. This will also protect us against possible overflows 1004 * while translating block count to bytes. 1005 */ 1006 if (size > INT_MAX) { 1007 DPRINTF("too large I/O: %zu bytes", size); 1008 return (EIO); 1009 } 1010 1011 blks = size / bd->bd_sectorsize; 1012 if (blks == 0 || (size % bd->bd_sectorsize) != 0) 1013 blks++; 1014 1015 if (dblk > dblk + blks) 1016 return (EIO); 1017 1018 if (rsize) 1019 *rsize = 0; 1020 1021 /* 1022 * Get disk blocks, this value is either for whole disk or for 1023 * partition. 1024 */ 1025 d_offset = 0; 1026 disk_blocks = 0; 1027 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 1028 if (disk_ioctl(dev, DIOCGMEDIASIZE, &disk_blocks) == 0) { 1029 /* DIOCGMEDIASIZE does return bytes. */ 1030 disk_blocks /= bd->bd_sectorsize; 1031 } 1032 d_offset = dev->d_offset; 1033 } 1034 if (disk_blocks == 0) 1035 disk_blocks = bd->bd_sectors * (bd->bd_sectorsize / 1036 BIOSDISK_SECSIZE) - d_offset; 1037 1038 /* Validate source block address. */ 1039 if (dblk < d_offset || dblk >= d_offset + disk_blocks) 1040 return (EIO); 1041 1042 /* 1043 * Truncate if we are crossing disk or partition end. 1044 */ 1045 if (dblk + blks >= d_offset + disk_blocks) { 1046 blks = d_offset + disk_blocks - dblk; 1047 size = blks * bd->bd_sectorsize; 1048 DPRINTF("short I/O %d", blks); 1049 } 1050 1051 bio_size = min(BIO_BUFFER_SIZE, size); 1052 while (bio_size > bd->bd_sectorsize) { 1053 bbuf = bio_alloc(bio_size); 1054 if (bbuf != NULL) 1055 break; 1056 bio_size -= bd->bd_sectorsize; 1057 } 1058 if (bbuf == NULL) { 1059 bio_size = V86_IO_BUFFER_SIZE; 1060 if (bio_size / bd->bd_sectorsize == 0) 1061 panic("BUG: Real mode buffer is too small"); 1062 1063 /* Use alternate 4k buffer */ 1064 bbuf = PTOV(V86_IO_BUFFER); 1065 } 1066 rest = size; 1067 rc = 0; 1068 while (blks > 0) { 1069 int x = min(blks, bio_size / bd->bd_sectorsize); 1070 1071 switch (rw & F_MASK) { 1072 case F_READ: 1073 DPRINTF("read %d from %lld to %p", x, dblk, buf); 1074 bsize = bd->bd_sectorsize * x - blkoff; 1075 if (rest < bsize) 1076 bsize = rest; 1077 1078 if ((rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD)) != 0) { 1079 rc = EIO; 1080 goto error; 1081 } 1082 1083 bcopy(bbuf + blkoff, buf, bsize); 1084 break; 1085 case F_WRITE : 1086 DPRINTF("write %d from %lld to %p", x, dblk, buf); 1087 if (blkoff != 0) { 1088 /* 1089 * We got offset to sector, read 1 sector to 1090 * bbuf. 1091 */ 1092 x = 1; 1093 bsize = bd->bd_sectorsize - blkoff; 1094 bsize = min(bsize, rest); 1095 rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD); 1096 } else if (rest < bd->bd_sectorsize) { 1097 /* 1098 * The remaining block is not full 1099 * sector. Read 1 sector to bbuf. 1100 */ 1101 x = 1; 1102 bsize = rest; 1103 rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD); 1104 } else { 1105 /* We can write full sector(s). */ 1106 bsize = bd->bd_sectorsize * x; 1107 } 1108 /* 1109 * Put your Data In, Put your Data out, 1110 * Put your Data In, and shake it all about 1111 */ 1112 bcopy(buf, bbuf + blkoff, bsize); 1113 if ((rc = bd_io(dev, bd, dblk, x, bbuf, BD_WR)) != 0) { 1114 rc = EIO; 1115 goto error; 1116 } 1117 1118 break; 1119 default: 1120 /* DO NOTHING */ 1121 rc = EROFS; 1122 goto error; 1123 } 1124 1125 blkoff = 0; 1126 buf += bsize; 1127 rest -= bsize; 1128 blks -= x; 1129 dblk += x; 1130 } 1131 1132 if (rsize != NULL) 1133 *rsize = size; 1134 error: 1135 if (bbuf != PTOV(V86_IO_BUFFER)) 1136 bio_free(bbuf, bio_size); 1137 return (rc); 1138 } 1139 1140 static int 1141 bd_edd_io(bdinfo_t *bd, daddr_t dblk, int blks, caddr_t dest, 1142 int dowrite) 1143 { 1144 static struct edd_packet packet; 1145 1146 TSENTER(); 1147 1148 packet.len = sizeof(struct edd_packet); 1149 packet.count = blks; 1150 packet.off = VTOPOFF(dest); 1151 packet.seg = VTOPSEG(dest); 1152 packet.lba = dblk; 1153 v86.ctl = V86_FLAGS; 1154 v86.addr = DISK_BIOS; 1155 if (dowrite == BD_WR) 1156 v86.eax = CMD_WRITE_LBA; /* maybe Write with verify 0x4302? */ 1157 else 1158 v86.eax = CMD_READ_LBA; 1159 v86.edx = bd->bd_unit; 1160 v86.ds = VTOPSEG(&packet); 1161 v86.esi = VTOPOFF(&packet); 1162 v86int(); 1163 if (V86_CY(v86.efl)) 1164 return (v86.eax >> 8); 1165 1166 TSEXIT(); 1167 return (0); 1168 } 1169 1170 static int 1171 bd_chs_io(bdinfo_t *bd, daddr_t dblk, int blks, caddr_t dest, 1172 int dowrite) 1173 { 1174 uint32_t x, bpc, cyl, hd, sec; 1175 1176 TSENTER(); 1177 1178 bpc = bd->bd_sec * bd->bd_hds; /* blocks per cylinder */ 1179 x = dblk; 1180 cyl = x / bpc; /* block # / blocks per cylinder */ 1181 x %= bpc; /* block offset into cylinder */ 1182 hd = x / bd->bd_sec; /* offset / blocks per track */ 1183 sec = x % bd->bd_sec; /* offset into track */ 1184 1185 /* correct sector number for 1-based BIOS numbering */ 1186 sec++; 1187 1188 if (cyl > 1023) { 1189 /* CHS doesn't support cylinders > 1023. */ 1190 return (1); 1191 } 1192 1193 v86.ctl = V86_FLAGS; 1194 v86.addr = DISK_BIOS; 1195 if (dowrite == BD_WR) 1196 v86.eax = CMD_WRITE_CHS | blks; 1197 else 1198 v86.eax = CMD_READ_CHS | blks; 1199 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec; 1200 v86.edx = (hd << 8) | bd->bd_unit; 1201 v86.es = VTOPSEG(dest); 1202 v86.ebx = VTOPOFF(dest); 1203 v86int(); 1204 if (V86_CY(v86.efl)) 1205 return (v86.eax >> 8); 1206 TSEXIT(); 1207 return (0); 1208 } 1209 1210 static void 1211 bd_io_workaround(bdinfo_t *bd) 1212 { 1213 uint8_t buf[8 * 1024]; 1214 1215 bd_edd_io(bd, 0xffffffff, 1, (caddr_t)buf, BD_RD); 1216 } 1217 1218 static int 1219 bd_io(struct disk_devdesc *dev, bdinfo_t *bd, daddr_t dblk, int blks, 1220 caddr_t dest, int dowrite) 1221 { 1222 int result, retry; 1223 1224 TSENTER(); 1225 1226 /* Just in case some idiot actually tries to read/write -1 blocks... */ 1227 if (blks < 0) 1228 return (-1); 1229 1230 /* 1231 * Workaround for a problem with some HP ProLiant BIOS failing to work 1232 * out the boot disk after installation. hrs and kuriyama discovered 1233 * this problem with an HP ProLiant DL320e Gen 8 with a 3TB HDD, and 1234 * discovered that an int13h call seems to cause a buffer overrun in 1235 * the bios. The problem is alleviated by doing an extra read before 1236 * the buggy read. It is not immediately known whether other models 1237 * are similarly affected. 1238 * Loop retrying the operation a couple of times. The BIOS 1239 * may also retry. 1240 */ 1241 if (dowrite == BD_RD && dblk >= 0x100000000) 1242 bd_io_workaround(bd); 1243 for (retry = 0; retry < 3; retry++) { 1244 if (bd->bd_flags & BD_MODEEDD) 1245 result = bd_edd_io(bd, dblk, blks, dest, dowrite); 1246 else 1247 result = bd_chs_io(bd, dblk, blks, dest, dowrite); 1248 1249 if (result == 0) { 1250 if (bd->bd_flags & BD_NO_MEDIA) 1251 bd->bd_flags &= ~BD_NO_MEDIA; 1252 break; 1253 } 1254 1255 bd_reset_disk(bd->bd_unit); 1256 1257 /* 1258 * Error codes: 1259 * 20h controller failure 1260 * 31h no media in drive (IBM/MS INT 13 extensions) 1261 * 80h no media in drive, VMWare (Fusion) 1262 * There is no reason to repeat the IO with errors above. 1263 */ 1264 if (result == 0x20 || result == 0x31 || result == 0x80) { 1265 bd->bd_flags |= BD_NO_MEDIA; 1266 break; 1267 } 1268 } 1269 1270 if (result != 0 && (bd->bd_flags & BD_NO_MEDIA) == 0) { 1271 if (dowrite == BD_WR) { 1272 printf("%s%d: Write %d sector(s) from %p (0x%x) " 1273 "to %lld: 0x%x\n", dev->dd.d_dev->dv_name, 1274 dev->dd.d_unit, blks, dest, VTOP(dest), dblk, 1275 result); 1276 } else { 1277 printf("%s%d: Read %d sector(s) from %lld to %p " 1278 "(0x%x): 0x%x\n", dev->dd.d_dev->dv_name, 1279 dev->dd.d_unit, blks, dblk, dest, VTOP(dest), 1280 result); 1281 } 1282 } 1283 1284 TSEXIT(); 1285 1286 return (result); 1287 } 1288 1289 /* 1290 * Return a suitable dev_t value for (dev). 1291 * 1292 * In the case where it looks like (dev) is a SCSI disk, we allow the number of 1293 * IDE disks to be specified in $num_ide_disks. There should be a Better Way. 1294 */ 1295 int 1296 bd_getdev(struct i386_devdesc *d) 1297 { 1298 struct disk_devdesc *dev; 1299 bdinfo_t *bd; 1300 int biosdev; 1301 int major; 1302 int rootdev; 1303 char *nip, *cp; 1304 int i, unit, slice, partition; 1305 1306 /* XXX: Assume partition 'a'. */ 1307 slice = 0; 1308 partition = 0; 1309 1310 dev = (struct disk_devdesc *)d; 1311 bd = bd_get_bdinfo(&dev->dd); 1312 if (bd == NULL) 1313 return (-1); 1314 1315 biosdev = bd_unit2bios(d); 1316 DPRINTF("unit %d BIOS device %d", dev->dd.d_unit, biosdev); 1317 if (biosdev == -1) /* not a BIOS device */ 1318 return (-1); 1319 1320 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 1321 if (disk_open(dev, bd->bd_sectors * bd->bd_sectorsize, 1322 bd->bd_sectorsize) != 0) /* oops, not a viable device */ 1323 return (-1); 1324 else 1325 disk_close(dev); 1326 slice = dev->d_slice + 1; 1327 partition = dev->d_partition; 1328 } 1329 1330 if (biosdev < 0x80) { 1331 /* floppy (or emulated floppy) or ATAPI device */ 1332 if (bd->bd_type == DT_ATAPI) { 1333 /* is an ATAPI disk */ 1334 major = WFDMAJOR; 1335 } else { 1336 /* is a floppy disk */ 1337 major = FDMAJOR; 1338 } 1339 } else { 1340 /* assume an IDE disk */ 1341 major = WDMAJOR; 1342 } 1343 /* default root disk unit number */ 1344 unit = biosdev & 0x7f; 1345 1346 if (dev->dd.d_dev->dv_type == DEVT_CD) { 1347 /* 1348 * XXX: Need to examine device spec here to figure out if 1349 * SCSI or ATAPI. No idea on how to figure out device number. 1350 * All we can really pass to the kernel is what bus and device 1351 * on which bus we were booted from, which dev_t isn't well 1352 * suited to since those number don't match to unit numbers 1353 * very well. We may just need to engage in a hack where 1354 * we pass -C to the boot args if we are the boot device. 1355 */ 1356 major = ACDMAJOR; 1357 unit = 0; /* XXX */ 1358 } 1359 1360 /* XXX a better kludge to set the root disk unit number */ 1361 if ((nip = getenv("root_disk_unit")) != NULL) { 1362 i = strtol(nip, &cp, 0); 1363 /* check for parse error */ 1364 if ((cp != nip) && (*cp == 0)) 1365 unit = i; 1366 } 1367 1368 rootdev = MAKEBOOTDEV(major, slice, unit, partition); 1369 DPRINTF("dev is 0x%x\n", rootdev); 1370 return (rootdev); 1371 } 1372