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 = NULL 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 = NULL 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 = NULL 193 }; 194 195 static bdinfo_list_t * 196 bd_get_bdinfo_list(struct devsw *dev) 197 { 198 if (dev->dv_type == DEVT_DISK) 199 return (&hdinfo); 200 if (dev->dv_type == DEVT_CD) 201 return (&cdinfo); 202 if (dev->dv_type == DEVT_FD) 203 return (&fdinfo); 204 return (NULL); 205 } 206 207 /* XXX this gets called way way too often, investigate */ 208 static bdinfo_t * 209 bd_get_bdinfo(struct devdesc *dev) 210 { 211 bdinfo_list_t *bdi; 212 bdinfo_t *bd = NULL; 213 int unit; 214 215 bdi = bd_get_bdinfo_list(dev->d_dev); 216 if (bdi == NULL) 217 return (bd); 218 219 unit = 0; 220 STAILQ_FOREACH(bd, bdi, bd_link) { 221 if (unit == dev->d_unit) 222 return (bd); 223 unit++; 224 } 225 return (bd); 226 } 227 228 /* 229 * Translate between BIOS device numbers and our private unit numbers. 230 */ 231 int 232 bd_bios2unit(int biosdev) 233 { 234 bdinfo_list_t *bdi[] = { &fdinfo, &cdinfo, &hdinfo, NULL }; 235 bdinfo_t *bd; 236 int i, unit; 237 238 DPRINTF("looking for bios device 0x%x", biosdev); 239 for (i = 0; bdi[i] != NULL; i++) { 240 unit = 0; 241 STAILQ_FOREACH(bd, bdi[i], bd_link) { 242 if (bd->bd_unit == biosdev) { 243 DPRINTF("bd unit %d is BIOS device 0x%x", unit, 244 bd->bd_unit); 245 return (unit); 246 } 247 unit++; 248 } 249 } 250 return (-1); 251 } 252 253 int 254 bd_unit2bios(struct i386_devdesc *dev) 255 { 256 bdinfo_list_t *bdi; 257 bdinfo_t *bd; 258 int unit; 259 260 bdi = bd_get_bdinfo_list(dev->dd.d_dev); 261 if (bdi == NULL) 262 return (-1); 263 264 unit = 0; 265 STAILQ_FOREACH(bd, bdi, bd_link) { 266 if (unit == dev->dd.d_unit) 267 return (bd->bd_unit); 268 unit++; 269 } 270 return (-1); 271 } 272 273 /* 274 * Use INT13 AH=15 - Read Drive Type. 275 */ 276 static int 277 fd_count(void) 278 { 279 int drive; 280 281 for (drive = 0; drive < MAXBDDEV; drive++) { 282 bd_reset_disk(drive); 283 284 v86.ctl = V86_FLAGS; 285 v86.addr = DISK_BIOS; 286 v86.eax = CMD_DRIVE_TYPE; 287 v86.edx = drive; 288 v86int(); 289 290 if (V86_CY(v86.efl)) 291 break; 292 293 if ((v86.eax & 0x300) == 0) 294 break; 295 } 296 297 return (drive); 298 } 299 300 /* 301 * Quiz the BIOS for disk devices, save a little info about them. 302 */ 303 static int 304 fd_init(void) 305 { 306 int unit, numfd; 307 bdinfo_t *bd; 308 309 numfd = fd_count(); 310 for (unit = 0; unit < numfd; unit++) { 311 if ((bd = calloc(1, sizeof(*bd))) == NULL) 312 break; 313 314 bd->bd_sectorsize = BIOSDISK_SECSIZE; 315 bd->bd_flags = BD_FLOPPY; 316 bd->bd_unit = unit; 317 318 /* Use std diskinfo for floppy drive */ 319 if (bd_get_diskinfo_std(bd) != 0) { 320 free(bd); 321 break; 322 } 323 if (bd->bd_sectors == 0) 324 bd->bd_flags |= BD_NO_MEDIA; 325 326 printf("BIOS drive %c: is %s%d\n", ('A' + unit), 327 biosfd.dv_name, unit); 328 329 STAILQ_INSERT_TAIL(&fdinfo, bd, bd_link); 330 } 331 332 bcache_add_dev(unit); 333 return (0); 334 } 335 336 static int 337 bd_init(void) 338 { 339 int base, unit; 340 bdinfo_t *bd; 341 342 TSENTER(); 343 344 base = 0x80; 345 for (unit = 0; unit < *(unsigned char *)PTOV(BIOS_NUMDRIVES); unit++) { 346 /* 347 * Check the BIOS equipment list for number of fixed disks. 348 */ 349 if ((bd = calloc(1, sizeof(*bd))) == NULL) 350 break; 351 bd->bd_unit = base + unit; 352 if (!bd_int13probe(bd)) { 353 free(bd); 354 break; 355 } 356 357 printf("BIOS drive %c: is %s%d\n", ('C' + unit), 358 bioshd.dv_name, unit); 359 360 STAILQ_INSERT_TAIL(&hdinfo, bd, bd_link); 361 } 362 bcache_add_dev(unit); 363 TSEXIT(); 364 return (0); 365 } 366 367 /* 368 * We can't quiz, we have to be told what device to use, so this function 369 * doesn't do anything. Instead, the loader calls bc_add() with the BIOS 370 * device number to add. 371 */ 372 static int 373 cd_init(void) 374 { 375 376 return (0); 377 } 378 379 /* 380 * Information from bootable CD-ROM. 381 */ 382 static int 383 bd_get_diskinfo_cd(struct bdinfo *bd) 384 { 385 struct specification_packet bc_sp; 386 int ret = -1; 387 388 (void) memset(&bc_sp, 0, sizeof (bc_sp)); 389 /* Set sp_size as per specification. */ 390 bc_sp.sp_size = sizeof (bc_sp) - sizeof (bc_sp.sp_dummy); 391 392 v86.ctl = V86_FLAGS; 393 v86.addr = DISK_BIOS; 394 v86.eax = CMD_CD_GET_STATUS; 395 v86.edx = bd->bd_unit; 396 v86.ds = VTOPSEG(&bc_sp); 397 v86.esi = VTOPOFF(&bc_sp); 398 v86int(); 399 400 if ((v86.eax & 0xff00) == 0 && 401 bc_sp.sp_drive == bd->bd_unit) { 402 bd->bd_cyl = ((bc_sp.sp_cylsec & 0xc0) << 2) + 403 ((bc_sp.sp_cylsec & 0xff00) >> 8) + 1; 404 bd->bd_sec = bc_sp.sp_cylsec & 0x3f; 405 bd->bd_hds = bc_sp.sp_head + 1; 406 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 407 408 if (bc_sp.sp_bootmedia & 0x0F) { 409 /* Floppy or hard-disk emulation */ 410 bd->bd_sectorsize = BIOSDISK_SECSIZE; 411 return (-1); 412 } else { 413 bd->bd_sectorsize = 2048; 414 bd->bd_flags = BD_MODEEDD | BD_CDROM; 415 ret = 0; 416 } 417 } 418 419 /* 420 * If this is the boot_drive, default to non-emulation bootable CD-ROM. 421 */ 422 if (ret != 0 && bd->bd_unit >= 0x88) { 423 bd->bd_cyl = 0; 424 bd->bd_hds = 1; 425 bd->bd_sec = 15; 426 bd->bd_sectorsize = 2048; 427 bd->bd_flags = BD_MODEEDD | BD_CDROM; 428 bd->bd_sectors = 0; 429 ret = 0; 430 } 431 432 /* 433 * Note we can not use bd_get_diskinfo_ext() nor bd_get_diskinfo_std() 434 * here - some systems do get hung with those. 435 */ 436 /* 437 * Still no size? use 7.961GB. The size does not really matter 438 * as long as it is reasonably large to make our reads to pass 439 * the sector count check. 440 */ 441 if (bd->bd_sectors == 0) 442 bd->bd_sectors = 4173824; 443 444 return (ret); 445 } 446 447 int 448 bc_add(int biosdev) 449 { 450 bdinfo_t *bd; 451 int nbcinfo = 0; 452 453 if (!STAILQ_EMPTY(&cdinfo)) 454 return (-1); 455 456 if ((bd = calloc(1, sizeof(*bd))) == NULL) 457 return (-1); 458 459 bd->bd_unit = biosdev; 460 if (bd_get_diskinfo_cd(bd) < 0) { 461 free(bd); 462 return (-1); 463 } 464 465 STAILQ_INSERT_TAIL(&cdinfo, bd, bd_link); 466 printf("BIOS CD is cd%d\n", nbcinfo); 467 nbcinfo++; 468 bcache_add_dev(nbcinfo); /* register cd device in bcache */ 469 return(0); 470 } 471 472 /* 473 * Return EDD version or 0 if EDD is not supported on this drive. 474 */ 475 static int 476 bd_check_extensions(int unit) 477 { 478 /* do not use ext calls for floppy devices */ 479 if (unit < 0x80) 480 return (0); 481 482 /* Determine if we can use EDD with this device. */ 483 v86.ctl = V86_FLAGS; 484 v86.addr = DISK_BIOS; 485 v86.eax = CMD_CHECK_EDD; 486 v86.edx = unit; 487 v86.ebx = EDD_QUERY_MAGIC; 488 v86int(); 489 490 if (V86_CY(v86.efl) || /* carry set */ 491 (v86.ebx & 0xffff) != EDD_INSTALLED) /* signature */ 492 return (0); 493 494 /* extended disk access functions (AH=42h-44h,47h,48h) supported */ 495 if ((v86.ecx & EDD_INTERFACE_FIXED_DISK) == 0) 496 return (0); 497 498 return ((v86.eax >> 8) & 0xff); 499 } 500 501 static void 502 bd_reset_disk(int unit) 503 { 504 /* reset disk */ 505 v86.ctl = V86_FLAGS; 506 v86.addr = DISK_BIOS; 507 v86.eax = CMD_RESET; 508 v86.edx = unit; 509 v86int(); 510 } 511 512 /* 513 * Read CHS info. Return 0 on success, error otherwise. 514 */ 515 static int 516 bd_get_diskinfo_std(struct bdinfo *bd) 517 { 518 bzero(&v86, sizeof(v86)); 519 v86.ctl = V86_FLAGS; 520 v86.addr = DISK_BIOS; 521 v86.eax = CMD_READ_PARAM; 522 v86.edx = bd->bd_unit; 523 v86int(); 524 525 if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0)) 526 return ((v86.eax & 0xff00) >> 8); 527 528 /* return custom error on absurd sector number */ 529 if ((v86.ecx & 0x3f) == 0) 530 return (0x60); 531 532 bd->bd_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1; 533 /* Convert max head # -> # of heads */ 534 bd->bd_hds = ((v86.edx & 0xff00) >> 8) + 1; 535 bd->bd_sec = v86.ecx & 0x3f; 536 bd->bd_type = v86.ebx; 537 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 538 539 return (0); 540 } 541 542 /* 543 * Read EDD info. Return 0 on success, error otherwise. 544 * 545 * Avoid stack corruption on some systems by adding extra bytes to 546 * params block. 547 */ 548 static int 549 bd_get_diskinfo_ext(struct bdinfo *bd) 550 { 551 struct disk_params { 552 struct edd_params head; 553 struct edd_device_path_v3 device_path; 554 uint8_t dummy[16]; 555 } __packed dparams; 556 struct edd_params *params; 557 uint64_t total; 558 559 params = &dparams.head; 560 561 /* Get disk params */ 562 bzero(&dparams, sizeof(dparams)); 563 params->len = sizeof(struct edd_params_v3); 564 v86.ctl = V86_FLAGS; 565 v86.addr = DISK_BIOS; 566 v86.eax = CMD_EXT_PARAM; 567 v86.edx = bd->bd_unit; 568 v86.ds = VTOPSEG(&dparams); 569 v86.esi = VTOPOFF(&dparams); 570 v86int(); 571 572 if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0)) 573 return ((v86.eax & 0xff00) >> 8); 574 575 /* 576 * Sector size must be a multiple of 512 bytes. 577 * An alternate test would be to check power of 2, 578 * powerof2(params.sector_size). 579 * 16K is largest read buffer we can use at this time. 580 */ 581 if (params->sector_size >= 512 && 582 params->sector_size <= 16384 && 583 (params->sector_size % BIOSDISK_SECSIZE) == 0) 584 bd->bd_sectorsize = params->sector_size; 585 586 bd->bd_cyl = params->cylinders; 587 bd->bd_hds = params->heads; 588 bd->bd_sec = params->sectors_per_track; 589 590 if (params->sectors != 0) { 591 total = params->sectors; 592 } else { 593 total = (uint64_t)params->cylinders * 594 params->heads * params->sectors_per_track; 595 } 596 bd->bd_sectors = total; 597 598 return (0); 599 } 600 601 /* 602 * Try to detect a device supported by the legacy int13 BIOS 603 */ 604 static bool 605 bd_int13probe(bdinfo_t *bd) 606 { 607 int edd, ret; 608 609 bd->bd_flags &= ~BD_NO_MEDIA; 610 611 if ((bd->bd_flags & BD_CDROM) != 0) { 612 return (bd_get_diskinfo_cd(bd) == 0); 613 } 614 615 edd = bd_check_extensions(bd->bd_unit); 616 if (edd == 0) 617 bd->bd_flags |= BD_MODEINT13; 618 else if (edd < 0x30) 619 bd->bd_flags |= BD_MODEEDD1; 620 else 621 bd->bd_flags |= BD_MODEEDD3; 622 623 /* Default sector size */ 624 if (bd->bd_sectorsize == 0) 625 bd->bd_sectorsize = BIOSDISK_SECSIZE; 626 627 /* 628 * Test if the floppy device is present, so we can avoid receiving 629 * bogus information from bd_get_diskinfo_std(). 630 */ 631 if (bd->bd_unit < 0x80) { 632 /* reset disk */ 633 bd_reset_disk(bd->bd_unit); 634 635 /* Get disk type */ 636 v86.ctl = V86_FLAGS; 637 v86.addr = DISK_BIOS; 638 v86.eax = CMD_DRIVE_TYPE; 639 v86.edx = bd->bd_unit; 640 v86int(); 641 if (V86_CY(v86.efl) || (v86.eax & 0x300) == 0) 642 return (false); 643 } 644 645 ret = 1; 646 if (edd != 0) 647 ret = bd_get_diskinfo_ext(bd); 648 if (ret != 0 || bd->bd_sectors == 0) 649 ret = bd_get_diskinfo_std(bd); 650 651 if (ret != 0 && bd->bd_unit < 0x80) { 652 /* Set defaults for 1.44 floppy */ 653 bd->bd_cyl = 80; 654 bd->bd_hds = 2; 655 bd->bd_sec = 18; 656 bd->bd_sectors = 2880; 657 /* Since we are there, there most likely is no media */ 658 bd->bd_flags |= BD_NO_MEDIA; 659 ret = 0; 660 } 661 662 if (ret != 0) { 663 if (bd->bd_sectors != 0 && edd != 0) { 664 bd->bd_sec = 63; 665 bd->bd_hds = 255; 666 bd->bd_cyl = 667 (bd->bd_sectors + bd->bd_sec * bd->bd_hds - 1) / 668 bd->bd_sec * bd->bd_hds; 669 } else { 670 const char *dv_name; 671 672 if ((bd->bd_flags & BD_FLOPPY) != 0) 673 dv_name = biosfd.dv_name; 674 else 675 dv_name = bioshd.dv_name; 676 677 printf("Can not get information about %s unit %#x\n", 678 dv_name, bd->bd_unit); 679 return (false); 680 } 681 } 682 683 if (bd->bd_sec == 0) 684 bd->bd_sec = 63; 685 if (bd->bd_hds == 0) 686 bd->bd_hds = 255; 687 688 if (bd->bd_sectors == 0) 689 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 690 691 DPRINTF("unit 0x%x geometry %d/%d/%d\n", bd->bd_unit, bd->bd_cyl, 692 bd->bd_hds, bd->bd_sec); 693 694 return (true); 695 } 696 697 static int 698 bd_count(bdinfo_list_t *bdi) 699 { 700 bdinfo_t *bd; 701 int i; 702 703 i = 0; 704 STAILQ_FOREACH(bd, bdi, bd_link) 705 i++; 706 return (i); 707 } 708 709 /* 710 * Print information about disks 711 */ 712 static int 713 bd_print_common(struct devsw *dev, bdinfo_list_t *bdi, int verbose) 714 { 715 char line[80]; 716 struct disk_devdesc devd; 717 bdinfo_t *bd; 718 int i, ret = 0; 719 char drive; 720 721 if (STAILQ_EMPTY(bdi)) 722 return (0); 723 724 printf("%s devices:", dev->dv_name); 725 if ((ret = pager_output("\n")) != 0) 726 return (ret); 727 728 i = -1; 729 STAILQ_FOREACH(bd, bdi, bd_link) { 730 i++; 731 732 switch (dev->dv_type) { 733 case DEVT_FD: 734 drive = 'A'; 735 break; 736 case DEVT_CD: 737 drive = 'C' + bd_count(&hdinfo); 738 break; 739 default: 740 drive = 'C'; 741 break; 742 } 743 744 snprintf(line, sizeof(line), 745 " %s%d: BIOS drive %c (%s%ju X %u):\n", 746 dev->dv_name, i, drive + i, 747 (bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA ? 748 "no media, " : "", 749 (uintmax_t)bd->bd_sectors, 750 bd->bd_sectorsize); 751 if ((ret = pager_output(line)) != 0) 752 break; 753 754 if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 755 continue; 756 757 if (dev->dv_type != DEVT_DISK) 758 continue; 759 760 devd.dd.d_dev = dev; 761 devd.dd.d_unit = i; 762 devd.d_slice = D_SLICENONE; 763 devd.d_partition = D_PARTNONE; 764 if (disk_open(&devd, 765 bd->bd_sectorsize * bd->bd_sectors, 766 bd->bd_sectorsize) == 0) { 767 snprintf(line, sizeof(line), " %s%d", 768 dev->dv_name, i); 769 ret = disk_print(&devd, line, verbose); 770 disk_close(&devd); 771 if (ret != 0) 772 break; 773 } 774 } 775 return (ret); 776 } 777 778 static int 779 fd_print(int verbose) 780 { 781 return (bd_print_common(&biosfd, &fdinfo, verbose)); 782 } 783 784 static int 785 bd_print(int verbose) 786 { 787 return (bd_print_common(&bioshd, &hdinfo, verbose)); 788 } 789 790 static int 791 cd_print(int verbose) 792 { 793 return (bd_print_common(&bioscd, &cdinfo, verbose)); 794 } 795 796 /* 797 * Read disk size from partition. 798 * This is needed to work around buggy BIOS systems returning 799 * wrong (truncated) disk media size. 800 * During bd_probe() we tested if the multiplication of bd_sectors 801 * would overflow so it should be safe to perform here. 802 */ 803 static uint64_t 804 bd_disk_get_sectors(struct disk_devdesc *dev) 805 { 806 bdinfo_t *bd; 807 struct disk_devdesc disk; 808 uint64_t size; 809 810 bd = bd_get_bdinfo(&dev->dd); 811 if (bd == NULL) 812 return (0); 813 814 disk.dd.d_dev = dev->dd.d_dev; 815 disk.dd.d_unit = dev->dd.d_unit; 816 disk.d_slice = D_SLICENONE; 817 disk.d_partition = D_PARTNONE; 818 disk.d_offset = 0; 819 820 size = bd->bd_sectors * bd->bd_sectorsize; 821 if (disk_open(&disk, size, bd->bd_sectorsize) == 0) { 822 (void) disk_ioctl(&disk, DIOCGMEDIASIZE, &size); 823 disk_close(&disk); 824 } 825 return (size / bd->bd_sectorsize); 826 } 827 828 /* 829 * Attempt to open the disk described by (dev) for use by (f). 830 * 831 * Note that the philosophy here is "give them exactly what 832 * they ask for". This is necessary because being too "smart" 833 * about what the user might want leads to complications. 834 * (eg. given no slice or partition value, with a disk that is 835 * sliced - are they after the first BSD slice, or the DOS 836 * slice before it?) 837 */ 838 static int 839 bd_open(struct open_file *f, ...) 840 { 841 bdinfo_t *bd; 842 struct disk_devdesc *dev; 843 va_list ap; 844 int rc; 845 846 TSENTER(); 847 848 va_start(ap, f); 849 dev = va_arg(ap, struct disk_devdesc *); 850 va_end(ap); 851 852 bd = bd_get_bdinfo(&dev->dd); 853 if (bd == NULL) 854 return (EIO); 855 856 if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) { 857 if (!bd_int13probe(bd)) 858 return (EIO); 859 if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 860 return (EIO); 861 } 862 if (bd->bd_bcache == NULL) 863 bd->bd_bcache = bcache_allocate(); 864 865 if (bd->bd_open == 0) 866 bd->bd_sectors = bd_disk_get_sectors(dev); 867 bd->bd_open++; 868 869 rc = 0; 870 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 871 rc = disk_open(dev, bd->bd_sectors * bd->bd_sectorsize, 872 bd->bd_sectorsize); 873 if (rc != 0) { 874 bd->bd_open--; 875 if (bd->bd_open == 0) { 876 bcache_free(bd->bd_bcache); 877 bd->bd_bcache = NULL; 878 } 879 } 880 } 881 TSEXIT(); 882 return (rc); 883 } 884 885 static int 886 bd_close(struct open_file *f) 887 { 888 struct disk_devdesc *dev; 889 bdinfo_t *bd; 890 int rc = 0; 891 892 dev = (struct disk_devdesc *)f->f_devdata; 893 bd = bd_get_bdinfo(&dev->dd); 894 if (bd == NULL) 895 return (EIO); 896 897 bd->bd_open--; 898 if (bd->bd_open == 0) { 899 bcache_free(bd->bd_bcache); 900 bd->bd_bcache = NULL; 901 } 902 if (dev->dd.d_dev->dv_type == DEVT_DISK) 903 rc = disk_close(dev); 904 return (rc); 905 } 906 907 static int 908 bd_ioctl(struct open_file *f, u_long cmd, void *data) 909 { 910 bdinfo_t *bd; 911 struct disk_devdesc *dev; 912 int rc; 913 914 dev = (struct disk_devdesc *)f->f_devdata; 915 bd = bd_get_bdinfo(&dev->dd); 916 if (bd == NULL) 917 return (EIO); 918 919 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 920 rc = disk_ioctl(dev, cmd, data); 921 if (rc != ENOTTY) 922 return (rc); 923 } 924 925 switch (cmd) { 926 case DIOCGSECTORSIZE: 927 *(uint32_t *)data = bd->bd_sectorsize; 928 break; 929 case DIOCGMEDIASIZE: 930 *(uint64_t *)data = bd->bd_sectors * bd->bd_sectorsize; 931 break; 932 default: 933 return (ENOTTY); 934 } 935 return (0); 936 } 937 938 static int 939 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, 940 char *buf, size_t *rsize) 941 { 942 bdinfo_t *bd; 943 struct bcache_devdata bcd; 944 struct disk_devdesc *dev; 945 daddr_t offset; 946 947 dev = (struct disk_devdesc *)devdata; 948 bd = bd_get_bdinfo(&dev->dd); 949 if (bd == NULL) 950 return (EINVAL); 951 952 bcd.dv_strategy = bd_realstrategy; 953 bcd.dv_devdata = devdata; 954 bcd.dv_cache = bd->bd_bcache; 955 956 offset = 0; 957 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 958 959 offset = dev->d_offset * bd->bd_sectorsize; 960 offset /= BIOSDISK_SECSIZE; 961 } 962 return (bcache_strategy(&bcd, rw, dblk + offset, size, 963 buf, rsize)); 964 } 965 966 static int 967 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, 968 char *buf, size_t *rsize) 969 { 970 struct disk_devdesc *dev = (struct disk_devdesc *)devdata; 971 bdinfo_t *bd; 972 uint64_t disk_blocks, offset, d_offset; 973 size_t blks, blkoff, bsize, bio_size, rest; 974 caddr_t bbuf = NULL; 975 int rc; 976 977 bd = bd_get_bdinfo(&dev->dd); 978 if (bd == NULL || (bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 979 return (EIO); 980 981 /* 982 * First make sure the IO size is a multiple of 512 bytes. While we do 983 * process partial reads below, the strategy mechanism is built 984 * assuming IO is a multiple of 512B blocks. If the request is not 985 * a multiple of 512B blocks, it has to be some sort of bug. 986 */ 987 if (size == 0 || (size % BIOSDISK_SECSIZE) != 0) { 988 printf("bd_strategy: %d bytes I/O not multiple of %d\n", 989 size, BIOSDISK_SECSIZE); 990 return (EIO); 991 } 992 993 DPRINTF("open_disk %p", dev); 994 995 offset = dblk * BIOSDISK_SECSIZE; 996 dblk = offset / bd->bd_sectorsize; 997 blkoff = offset % bd->bd_sectorsize; 998 999 /* 1000 * Check the value of the size argument. We do have quite small 1001 * heap (64MB), but we do not know good upper limit, so we check against 1002 * INT_MAX here. This will also protect us against possible overflows 1003 * while translating block count to bytes. 1004 */ 1005 if (size > INT_MAX) { 1006 DPRINTF("too large I/O: %zu bytes", size); 1007 return (EIO); 1008 } 1009 1010 blks = size / bd->bd_sectorsize; 1011 if (blks == 0 || (size % bd->bd_sectorsize) != 0) 1012 blks++; 1013 1014 if (dblk > dblk + blks) 1015 return (EIO); 1016 1017 if (rsize) 1018 *rsize = 0; 1019 1020 /* 1021 * Get disk blocks, this value is either for whole disk or for 1022 * partition. 1023 */ 1024 d_offset = 0; 1025 disk_blocks = 0; 1026 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 1027 if (disk_ioctl(dev, DIOCGMEDIASIZE, &disk_blocks) == 0) { 1028 /* DIOCGMEDIASIZE does return bytes. */ 1029 disk_blocks /= bd->bd_sectorsize; 1030 } 1031 d_offset = dev->d_offset; 1032 } 1033 if (disk_blocks == 0) 1034 disk_blocks = bd->bd_sectors - d_offset; 1035 1036 /* Validate source block address. */ 1037 if (dblk < d_offset || dblk >= d_offset + disk_blocks) 1038 return (EIO); 1039 1040 /* 1041 * Truncate if we are crossing disk or partition end. 1042 */ 1043 if (dblk + blks >= d_offset + disk_blocks) { 1044 blks = d_offset + disk_blocks - dblk; 1045 size = blks * bd->bd_sectorsize; 1046 DPRINTF("short I/O %d", blks); 1047 } 1048 1049 bio_size = min(BIO_BUFFER_SIZE, size); 1050 while (bio_size > bd->bd_sectorsize) { 1051 bbuf = bio_alloc(bio_size); 1052 if (bbuf != NULL) 1053 break; 1054 bio_size -= bd->bd_sectorsize; 1055 } 1056 if (bbuf == NULL) { 1057 bio_size = V86_IO_BUFFER_SIZE; 1058 if (bio_size / bd->bd_sectorsize == 0) 1059 panic("BUG: Real mode buffer is too small"); 1060 1061 /* Use alternate 4k buffer */ 1062 bbuf = PTOV(V86_IO_BUFFER); 1063 } 1064 rest = size; 1065 rc = 0; 1066 while (blks > 0) { 1067 int x = min(blks, bio_size / bd->bd_sectorsize); 1068 1069 switch (rw & F_MASK) { 1070 case F_READ: 1071 DPRINTF("read %d from %lld to %p", x, dblk, buf); 1072 bsize = bd->bd_sectorsize * x - blkoff; 1073 if (rest < bsize) 1074 bsize = rest; 1075 1076 if ((rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD)) != 0) { 1077 rc = EIO; 1078 goto error; 1079 } 1080 1081 bcopy(bbuf + blkoff, buf, bsize); 1082 break; 1083 case F_WRITE : 1084 DPRINTF("write %d from %lld to %p", x, dblk, buf); 1085 if (blkoff != 0) { 1086 /* 1087 * We got offset to sector, read 1 sector to 1088 * bbuf. 1089 */ 1090 x = 1; 1091 bsize = bd->bd_sectorsize - blkoff; 1092 bsize = min(bsize, rest); 1093 rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD); 1094 } else if (rest < bd->bd_sectorsize) { 1095 /* 1096 * The remaining block is not full 1097 * sector. Read 1 sector to bbuf. 1098 */ 1099 x = 1; 1100 bsize = rest; 1101 rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD); 1102 } else { 1103 /* We can write full sector(s). */ 1104 bsize = bd->bd_sectorsize * x; 1105 } 1106 /* 1107 * Put your Data In, Put your Data out, 1108 * Put your Data In, and shake it all about 1109 */ 1110 bcopy(buf, bbuf + blkoff, bsize); 1111 if ((rc = bd_io(dev, bd, dblk, x, bbuf, BD_WR)) != 0) { 1112 rc = EIO; 1113 goto error; 1114 } 1115 1116 break; 1117 default: 1118 /* DO NOTHING */ 1119 rc = EROFS; 1120 goto error; 1121 } 1122 1123 blkoff = 0; 1124 buf += bsize; 1125 rest -= bsize; 1126 blks -= x; 1127 dblk += x; 1128 } 1129 1130 if (rsize != NULL) 1131 *rsize = size; 1132 error: 1133 if (bbuf != PTOV(V86_IO_BUFFER)) 1134 bio_free(bbuf, bio_size); 1135 return (rc); 1136 } 1137 1138 static int 1139 bd_edd_io(bdinfo_t *bd, daddr_t dblk, int blks, caddr_t dest, 1140 int dowrite) 1141 { 1142 static struct edd_packet packet; 1143 1144 TSENTER(); 1145 1146 packet.len = sizeof(struct edd_packet); 1147 packet.count = blks; 1148 packet.off = VTOPOFF(dest); 1149 packet.seg = VTOPSEG(dest); 1150 packet.lba = dblk; 1151 v86.ctl = V86_FLAGS; 1152 v86.addr = DISK_BIOS; 1153 if (dowrite == BD_WR) 1154 v86.eax = CMD_WRITE_LBA; /* maybe Write with verify 0x4302? */ 1155 else 1156 v86.eax = CMD_READ_LBA; 1157 v86.edx = bd->bd_unit; 1158 v86.ds = VTOPSEG(&packet); 1159 v86.esi = VTOPOFF(&packet); 1160 v86int(); 1161 if (V86_CY(v86.efl)) 1162 return (v86.eax >> 8); 1163 1164 TSEXIT(); 1165 return (0); 1166 } 1167 1168 static int 1169 bd_chs_io(bdinfo_t *bd, daddr_t dblk, int blks, caddr_t dest, 1170 int dowrite) 1171 { 1172 uint32_t x, bpc, cyl, hd, sec; 1173 1174 TSENTER(); 1175 1176 bpc = bd->bd_sec * bd->bd_hds; /* blocks per cylinder */ 1177 x = dblk; 1178 cyl = x / bpc; /* block # / blocks per cylinder */ 1179 x %= bpc; /* block offset into cylinder */ 1180 hd = x / bd->bd_sec; /* offset / blocks per track */ 1181 sec = x % bd->bd_sec; /* offset into track */ 1182 1183 /* correct sector number for 1-based BIOS numbering */ 1184 sec++; 1185 1186 if (cyl > 1023) { 1187 /* CHS doesn't support cylinders > 1023. */ 1188 return (1); 1189 } 1190 1191 v86.ctl = V86_FLAGS; 1192 v86.addr = DISK_BIOS; 1193 if (dowrite == BD_WR) 1194 v86.eax = CMD_WRITE_CHS | blks; 1195 else 1196 v86.eax = CMD_READ_CHS | blks; 1197 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec; 1198 v86.edx = (hd << 8) | bd->bd_unit; 1199 v86.es = VTOPSEG(dest); 1200 v86.ebx = VTOPOFF(dest); 1201 v86int(); 1202 if (V86_CY(v86.efl)) 1203 return (v86.eax >> 8); 1204 TSEXIT(); 1205 return (0); 1206 } 1207 1208 static void 1209 bd_io_workaround(bdinfo_t *bd) 1210 { 1211 uint8_t buf[8 * 1024]; 1212 1213 bd_edd_io(bd, 0xffffffff, 1, (caddr_t)buf, BD_RD); 1214 } 1215 1216 static int 1217 bd_io(struct disk_devdesc *dev, bdinfo_t *bd, daddr_t dblk, int blks, 1218 caddr_t dest, int dowrite) 1219 { 1220 int result, retry; 1221 1222 TSENTER(); 1223 1224 /* Just in case some idiot actually tries to read/write -1 blocks... */ 1225 if (blks < 0) 1226 return (-1); 1227 1228 /* 1229 * Workaround for a problem with some HP ProLiant BIOS failing to work 1230 * out the boot disk after installation. hrs and kuriyama discovered 1231 * this problem with an HP ProLiant DL320e Gen 8 with a 3TB HDD, and 1232 * discovered that an int13h call seems to cause a buffer overrun in 1233 * the bios. The problem is alleviated by doing an extra read before 1234 * the buggy read. It is not immediately known whether other models 1235 * are similarly affected. 1236 * Loop retrying the operation a couple of times. The BIOS 1237 * may also retry. 1238 */ 1239 if (dowrite == BD_RD && dblk >= 0x100000000) 1240 bd_io_workaround(bd); 1241 for (retry = 0; retry < 3; retry++) { 1242 if (bd->bd_flags & BD_MODEEDD) 1243 result = bd_edd_io(bd, dblk, blks, dest, dowrite); 1244 else 1245 result = bd_chs_io(bd, dblk, blks, dest, dowrite); 1246 1247 if (result == 0) { 1248 if (bd->bd_flags & BD_NO_MEDIA) 1249 bd->bd_flags &= ~BD_NO_MEDIA; 1250 break; 1251 } 1252 1253 bd_reset_disk(bd->bd_unit); 1254 1255 /* 1256 * Error codes: 1257 * 20h controller failure 1258 * 31h no media in drive (IBM/MS INT 13 extensions) 1259 * 80h no media in drive, VMWare (Fusion) 1260 * There is no reason to repeat the IO with errors above. 1261 */ 1262 if (result == 0x20 || result == 0x31 || result == 0x80) { 1263 bd->bd_flags |= BD_NO_MEDIA; 1264 break; 1265 } 1266 } 1267 1268 if (result != 0 && (bd->bd_flags & BD_NO_MEDIA) == 0) { 1269 if (dowrite == BD_WR) { 1270 printf("%s%d: Write %d sector(s) from %p (0x%x) " 1271 "to %lld: 0x%x\n", dev->dd.d_dev->dv_name, 1272 dev->dd.d_unit, blks, dest, VTOP(dest), dblk, 1273 result); 1274 } else { 1275 printf("%s%d: Read %d sector(s) from %lld to %p " 1276 "(0x%x): 0x%x\n", dev->dd.d_dev->dv_name, 1277 dev->dd.d_unit, blks, dblk, dest, VTOP(dest), 1278 result); 1279 } 1280 } 1281 1282 TSEXIT(); 1283 1284 return (result); 1285 } 1286 1287 /* 1288 * Return the BIOS geometry of a given "fixed drive" in a format 1289 * suitable for the legacy bootinfo structure. Since the kernel is 1290 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we 1291 * prefer to get the information directly, rather than rely on being 1292 * able to put it together from information already maintained for 1293 * different purposes and for a probably different number of drives. 1294 * 1295 * For valid drives, the geometry is expected in the format (31..0) 1296 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are 1297 * indicated by returning the geometry of a "1.2M" PC-format floppy 1298 * disk. And, incidentally, what is returned is not the geometry as 1299 * such but the highest valid cylinder, head, and sector numbers. 1300 */ 1301 uint32_t 1302 bd_getbigeom(int bunit) 1303 { 1304 1305 v86.ctl = V86_FLAGS; 1306 v86.addr = DISK_BIOS; 1307 v86.eax = CMD_READ_PARAM; 1308 v86.edx = 0x80 + bunit; 1309 v86int(); 1310 if (V86_CY(v86.efl)) 1311 return (0x4f010f); 1312 return (((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) | 1313 (v86.edx & 0xff00) | (v86.ecx & 0x3f)); 1314 } 1315 1316 /* 1317 * Return a suitable dev_t value for (dev). 1318 * 1319 * In the case where it looks like (dev) is a SCSI disk, we allow the number of 1320 * IDE disks to be specified in $num_ide_disks. There should be a Better Way. 1321 */ 1322 int 1323 bd_getdev(struct i386_devdesc *d) 1324 { 1325 struct disk_devdesc *dev; 1326 bdinfo_t *bd; 1327 int biosdev; 1328 int major; 1329 int rootdev; 1330 char *nip, *cp; 1331 int i, unit, slice, partition; 1332 1333 /* XXX: Assume partition 'a'. */ 1334 slice = 0; 1335 partition = 0; 1336 1337 dev = (struct disk_devdesc *)d; 1338 bd = bd_get_bdinfo(&dev->dd); 1339 if (bd == NULL) 1340 return (-1); 1341 1342 biosdev = bd_unit2bios(d); 1343 DPRINTF("unit %d BIOS device %d", dev->dd.d_unit, biosdev); 1344 if (biosdev == -1) /* not a BIOS device */ 1345 return (-1); 1346 1347 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 1348 if (disk_open(dev, bd->bd_sectors * bd->bd_sectorsize, 1349 bd->bd_sectorsize) != 0) /* oops, not a viable device */ 1350 return (-1); 1351 else 1352 disk_close(dev); 1353 slice = dev->d_slice + 1; 1354 partition = dev->d_partition; 1355 } 1356 1357 if (biosdev < 0x80) { 1358 /* floppy (or emulated floppy) or ATAPI device */ 1359 if (bd->bd_type == DT_ATAPI) { 1360 /* is an ATAPI disk */ 1361 major = WFDMAJOR; 1362 } else { 1363 /* is a floppy disk */ 1364 major = FDMAJOR; 1365 } 1366 } else { 1367 /* assume an IDE disk */ 1368 major = WDMAJOR; 1369 } 1370 /* default root disk unit number */ 1371 unit = biosdev & 0x7f; 1372 1373 if (dev->dd.d_dev->dv_type == DEVT_CD) { 1374 /* 1375 * XXX: Need to examine device spec here to figure out if 1376 * SCSI or ATAPI. No idea on how to figure out device number. 1377 * All we can really pass to the kernel is what bus and device 1378 * on which bus we were booted from, which dev_t isn't well 1379 * suited to since those number don't match to unit numbers 1380 * very well. We may just need to engage in a hack where 1381 * we pass -C to the boot args if we are the boot device. 1382 */ 1383 major = ACDMAJOR; 1384 unit = 0; /* XXX */ 1385 } 1386 1387 /* XXX a better kludge to set the root disk unit number */ 1388 if ((nip = getenv("root_disk_unit")) != NULL) { 1389 i = strtol(nip, &cp, 0); 1390 /* check for parse error */ 1391 if ((cp != nip) && (*cp == 0)) 1392 unit = i; 1393 } 1394 1395 rootdev = MAKEBOOTDEV(major, slice, unit, partition); 1396 DPRINTF("dev is 0x%x\n", rootdev); 1397 return (rootdev); 1398 } 1399