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 #ifdef DISK_DEBUG 68 #define DPRINTF(fmt, args...) printf("%s: " fmt "\n", __func__, ## args) 69 #else 70 #define DPRINTF(fmt, args...) ((void)0) 71 #endif 72 73 struct specification_packet { 74 uint8_t sp_size; 75 uint8_t sp_bootmedia; 76 uint8_t sp_drive; 77 uint8_t sp_controller; 78 uint32_t sp_lba; 79 uint16_t sp_devicespec; 80 uint16_t sp_buffersegment; 81 uint16_t sp_loadsegment; 82 uint16_t sp_sectorcount; 83 uint16_t sp_cylsec; 84 uint8_t sp_head; 85 }; 86 87 /* 88 * List of BIOS devices, translation from disk unit number to 89 * BIOS unit number. 90 */ 91 typedef struct bdinfo 92 { 93 STAILQ_ENTRY(bdinfo) bd_link; /* link in device list */ 94 int bd_unit; /* BIOS unit number */ 95 int bd_cyl; /* BIOS geometry */ 96 int bd_hds; 97 int bd_sec; 98 int bd_flags; 99 #define BD_MODEINT13 0x0000 100 #define BD_MODEEDD1 0x0001 101 #define BD_MODEEDD3 0x0002 102 #define BD_MODEEDD (BD_MODEEDD1 | BD_MODEEDD3) 103 #define BD_MODEMASK 0x0003 104 #define BD_FLOPPY 0x0004 105 #define BD_CDROM 0x0008 106 #define BD_NO_MEDIA 0x0010 107 int bd_type; /* BIOS 'drive type' (floppy only) */ 108 uint16_t bd_sectorsize; /* Sector size */ 109 uint64_t bd_sectors; /* Disk size */ 110 int bd_open; /* reference counter */ 111 void *bd_bcache; /* buffer cache data */ 112 } bdinfo_t; 113 114 #define BD_RD 0 115 #define BD_WR 1 116 117 typedef STAILQ_HEAD(bdinfo_list, bdinfo) bdinfo_list_t; 118 static bdinfo_list_t fdinfo = STAILQ_HEAD_INITIALIZER(fdinfo); 119 static bdinfo_list_t cdinfo = STAILQ_HEAD_INITIALIZER(cdinfo); 120 static bdinfo_list_t hdinfo = STAILQ_HEAD_INITIALIZER(hdinfo); 121 122 static void bd_io_workaround(bdinfo_t *); 123 static int bd_io(struct disk_devdesc *, bdinfo_t *, daddr_t, int, caddr_t, int); 124 static bool bd_int13probe(bdinfo_t *); 125 126 static int bd_init(void); 127 static int cd_init(void); 128 static int fd_init(void); 129 static int bd_strategy(void *devdata, int flag, daddr_t dblk, size_t size, 130 char *buf, size_t *rsize); 131 static int bd_realstrategy(void *devdata, int flag, daddr_t dblk, size_t size, 132 char *buf, size_t *rsize); 133 static int bd_open(struct open_file *f, ...); 134 static int bd_close(struct open_file *f); 135 static int bd_ioctl(struct open_file *f, u_long cmd, void *data); 136 static int bd_print(int verbose); 137 static int cd_print(int verbose); 138 static int fd_print(int verbose); 139 static void bd_reset_disk(int); 140 static int bd_get_diskinfo_std(struct bdinfo *); 141 142 struct devsw biosfd = { 143 .dv_name = "fd", 144 .dv_type = DEVT_FD, 145 .dv_init = fd_init, 146 .dv_strategy = bd_strategy, 147 .dv_open = bd_open, 148 .dv_close = bd_close, 149 .dv_ioctl = bd_ioctl, 150 .dv_print = fd_print, 151 .dv_cleanup = NULL 152 }; 153 154 struct devsw bioscd = { 155 .dv_name = "cd", 156 .dv_type = DEVT_CD, 157 .dv_init = cd_init, 158 .dv_strategy = bd_strategy, 159 .dv_open = bd_open, 160 .dv_close = bd_close, 161 .dv_ioctl = bd_ioctl, 162 .dv_print = cd_print, 163 .dv_cleanup = NULL 164 }; 165 166 struct devsw bioshd = { 167 .dv_name = "disk", 168 .dv_type = DEVT_DISK, 169 .dv_init = bd_init, 170 .dv_strategy = bd_strategy, 171 .dv_open = bd_open, 172 .dv_close = bd_close, 173 .dv_ioctl = bd_ioctl, 174 .dv_print = bd_print, 175 .dv_cleanup = NULL 176 }; 177 178 static bdinfo_list_t * 179 bd_get_bdinfo_list(struct devsw *dev) 180 { 181 if (dev->dv_type == DEVT_DISK) 182 return (&hdinfo); 183 if (dev->dv_type == DEVT_CD) 184 return (&cdinfo); 185 if (dev->dv_type == DEVT_FD) 186 return (&fdinfo); 187 return (NULL); 188 } 189 190 /* XXX this gets called way way too often, investigate */ 191 static bdinfo_t * 192 bd_get_bdinfo(struct devdesc *dev) 193 { 194 bdinfo_list_t *bdi; 195 bdinfo_t *bd = NULL; 196 int unit; 197 198 bdi = bd_get_bdinfo_list(dev->d_dev); 199 if (bdi == NULL) 200 return (bd); 201 202 unit = 0; 203 STAILQ_FOREACH(bd, bdi, bd_link) { 204 if (unit == dev->d_unit) 205 return (bd); 206 unit++; 207 } 208 return (bd); 209 } 210 211 /* 212 * Translate between BIOS device numbers and our private unit numbers. 213 */ 214 int 215 bd_bios2unit(int biosdev) 216 { 217 bdinfo_list_t *bdi[] = { &fdinfo, &cdinfo, &hdinfo, NULL }; 218 bdinfo_t *bd; 219 int i, unit; 220 221 DPRINTF("looking for bios device 0x%x", biosdev); 222 for (i = 0; bdi[i] != NULL; i++) { 223 unit = 0; 224 STAILQ_FOREACH(bd, bdi[i], bd_link) { 225 if (bd->bd_unit == biosdev) { 226 DPRINTF("bd unit %d is BIOS device 0x%x", unit, 227 bd->bd_unit); 228 return (unit); 229 } 230 unit++; 231 } 232 } 233 return (-1); 234 } 235 236 int 237 bd_unit2bios(struct i386_devdesc *dev) 238 { 239 bdinfo_list_t *bdi; 240 bdinfo_t *bd; 241 int unit; 242 243 bdi = bd_get_bdinfo_list(dev->dd.d_dev); 244 if (bdi == NULL) 245 return (-1); 246 247 unit = 0; 248 STAILQ_FOREACH(bd, bdi, bd_link) { 249 if (unit == dev->dd.d_unit) 250 return (bd->bd_unit); 251 unit++; 252 } 253 return (-1); 254 } 255 256 /* 257 * Use INT13 AH=15 - Read Drive Type. 258 */ 259 static int 260 fd_count(void) 261 { 262 int drive; 263 264 for (drive = 0; drive < MAXBDDEV; drive++) { 265 bd_reset_disk(drive); 266 267 v86.ctl = V86_FLAGS; 268 v86.addr = 0x13; 269 v86.eax = 0x1500; 270 v86.edx = drive; 271 v86int(); 272 273 if (V86_CY(v86.efl)) 274 break; 275 276 if ((v86.eax & 0x300) == 0) 277 break; 278 } 279 280 return (drive); 281 } 282 283 /* 284 * Quiz the BIOS for disk devices, save a little info about them. 285 */ 286 static int 287 fd_init(void) 288 { 289 int unit, numfd; 290 bdinfo_t *bd; 291 292 numfd = fd_count(); 293 for (unit = 0; unit < numfd; unit++) { 294 if ((bd = calloc(1, sizeof(*bd))) == NULL) 295 break; 296 297 bd->bd_sectorsize = BIOSDISK_SECSIZE; 298 bd->bd_flags = BD_FLOPPY; 299 bd->bd_unit = unit; 300 301 /* Use std diskinfo for floppy drive */ 302 if (bd_get_diskinfo_std(bd) != 0) { 303 free(bd); 304 break; 305 } 306 if (bd->bd_sectors == 0) 307 bd->bd_flags |= BD_NO_MEDIA; 308 309 printf("BIOS drive %c: is %s%d\n", ('A' + unit), 310 biosfd.dv_name, unit); 311 312 STAILQ_INSERT_TAIL(&fdinfo, bd, bd_link); 313 } 314 315 bcache_add_dev(unit); 316 return (0); 317 } 318 319 static int 320 bd_init(void) 321 { 322 int base, unit; 323 bdinfo_t *bd; 324 325 base = 0x80; 326 for (unit = 0; unit < *(unsigned char *)PTOV(BIOS_NUMDRIVES); unit++) { 327 /* 328 * Check the BIOS equipment list for number of fixed disks. 329 */ 330 if ((bd = calloc(1, sizeof(*bd))) == NULL) 331 break; 332 bd->bd_unit = base + unit; 333 if (!bd_int13probe(bd)) { 334 free(bd); 335 break; 336 } 337 338 printf("BIOS drive %c: is %s%d\n", ('C' + unit), 339 bioshd.dv_name, unit); 340 341 STAILQ_INSERT_TAIL(&hdinfo, bd, bd_link); 342 } 343 bcache_add_dev(unit); 344 return (0); 345 } 346 347 /* 348 * We can't quiz, we have to be told what device to use, so this function 349 * doesn't do anything. Instead, the loader calls bc_add() with the BIOS 350 * device number to add. 351 */ 352 static int 353 cd_init(void) 354 { 355 356 return (0); 357 } 358 359 int 360 bc_add(int biosdev) 361 { 362 bdinfo_t *bd; 363 struct specification_packet bc_sp; 364 int nbcinfo = 0; 365 366 if (!STAILQ_EMPTY(&cdinfo)) 367 return (-1); 368 369 v86.ctl = V86_FLAGS; 370 v86.addr = 0x13; 371 v86.eax = 0x4b01; 372 v86.edx = biosdev; 373 v86.ds = VTOPSEG(&bc_sp); 374 v86.esi = VTOPOFF(&bc_sp); 375 v86int(); 376 if ((v86.eax & 0xff00) != 0) 377 return (-1); 378 379 if ((bd = calloc(1, sizeof(*bd))) == NULL) 380 return (-1); 381 382 bd->bd_flags = BD_CDROM; 383 bd->bd_unit = biosdev; 384 385 /* 386 * Ignore result from bd_int13probe(), we will use local 387 * workaround below. 388 */ 389 (void)bd_int13probe(bd); 390 391 if (bd->bd_cyl == 0) { 392 bd->bd_cyl = ((bc_sp.sp_cylsec & 0xc0) << 2) + 393 ((bc_sp.sp_cylsec & 0xff00) >> 8) + 1; 394 } 395 if (bd->bd_hds == 0) 396 bd->bd_hds = bc_sp.sp_head + 1; 397 if (bd->bd_sec == 0) 398 bd->bd_sec = bc_sp.sp_cylsec & 0x3f; 399 if (bd->bd_sectors == 0) 400 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 401 402 /* Still no size? use 7.961GB */ 403 if (bd->bd_sectors == 0) 404 bd->bd_sectors = 4173824; 405 406 STAILQ_INSERT_TAIL(&cdinfo, bd, bd_link); 407 printf("BIOS CD is cd%d\n", nbcinfo); 408 nbcinfo++; 409 bcache_add_dev(nbcinfo); /* register cd device in bcache */ 410 return(0); 411 } 412 413 /* 414 * Return EDD version or 0 if EDD is not supported on this drive. 415 */ 416 static int 417 bd_check_extensions(int unit) 418 { 419 /* do not use ext calls for floppy devices */ 420 if (unit < 0x80) 421 return (0); 422 423 /* Determine if we can use EDD with this device. */ 424 v86.ctl = V86_FLAGS; 425 v86.addr = 0x13; 426 v86.eax = 0x4100; 427 v86.edx = unit; 428 v86.ebx = 0x55aa; 429 v86int(); 430 431 if (V86_CY(v86.efl) || /* carry set */ 432 (v86.ebx & 0xffff) != 0xaa55) /* signature */ 433 return (0); 434 435 /* extended disk access functions (AH=42h-44h,47h,48h) supported */ 436 if ((v86.ecx & EDD_INTERFACE_FIXED_DISK) == 0) 437 return (0); 438 439 return ((v86.eax >> 8) & 0xff); 440 } 441 442 static void 443 bd_reset_disk(int unit) 444 { 445 /* reset disk */ 446 v86.ctl = V86_FLAGS; 447 v86.addr = 0x13; 448 v86.eax = 0; 449 v86.edx = unit; 450 v86int(); 451 } 452 453 /* 454 * Read CHS info. Return 0 on success, error otherwise. 455 */ 456 static int 457 bd_get_diskinfo_std(struct bdinfo *bd) 458 { 459 bzero(&v86, sizeof(v86)); 460 v86.ctl = V86_FLAGS; 461 v86.addr = 0x13; 462 v86.eax = 0x800; 463 v86.edx = bd->bd_unit; 464 v86int(); 465 466 if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0)) 467 return ((v86.eax & 0xff00) >> 8); 468 469 /* return custom error on absurd sector number */ 470 if ((v86.ecx & 0x3f) == 0) 471 return (0x60); 472 473 bd->bd_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1; 474 /* Convert max head # -> # of heads */ 475 bd->bd_hds = ((v86.edx & 0xff00) >> 8) + 1; 476 bd->bd_sec = v86.ecx & 0x3f; 477 bd->bd_type = v86.ebx; 478 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 479 480 return (0); 481 } 482 483 /* 484 * Read EDD info. Return 0 on success, error otherwise. 485 */ 486 static int 487 bd_get_diskinfo_ext(struct bdinfo *bd) 488 { 489 struct edd_params params; 490 uint64_t total; 491 492 /* Get disk params */ 493 bzero(¶ms, sizeof(params)); 494 params.len = sizeof(params); 495 v86.ctl = V86_FLAGS; 496 v86.addr = 0x13; 497 v86.eax = 0x4800; 498 v86.edx = bd->bd_unit; 499 v86.ds = VTOPSEG(¶ms); 500 v86.esi = VTOPOFF(¶ms); 501 v86int(); 502 503 if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0)) 504 return ((v86.eax & 0xff00) >> 8); 505 506 /* 507 * Sector size must be a multiple of 512 bytes. 508 * An alternate test would be to check power of 2, 509 * powerof2(params.sector_size). 510 * 16K is largest read buffer we can use at this time. 511 */ 512 if (params.sector_size >= 512 && 513 params.sector_size <= 16384 && 514 (params.sector_size % BIOSDISK_SECSIZE) == 0) 515 bd->bd_sectorsize = params.sector_size; 516 517 bd->bd_cyl = params.cylinders; 518 bd->bd_hds = params.heads; 519 bd->bd_sec = params.sectors_per_track; 520 521 if (params.sectors != 0) { 522 total = params.sectors; 523 } else { 524 total = (uint64_t)params.cylinders * 525 params.heads * params.sectors_per_track; 526 } 527 bd->bd_sectors = total; 528 529 return (0); 530 } 531 532 /* 533 * Try to detect a device supported by the legacy int13 BIOS 534 */ 535 static bool 536 bd_int13probe(bdinfo_t *bd) 537 { 538 int edd, ret; 539 540 bd->bd_flags &= ~BD_NO_MEDIA; 541 542 edd = bd_check_extensions(bd->bd_unit); 543 if (edd == 0) 544 bd->bd_flags |= BD_MODEINT13; 545 else if (edd < 0x30) 546 bd->bd_flags |= BD_MODEEDD1; 547 else 548 bd->bd_flags |= BD_MODEEDD3; 549 550 /* Default sector size */ 551 bd->bd_sectorsize = BIOSDISK_SECSIZE; 552 553 /* 554 * Test if the floppy device is present, so we can avoid receiving 555 * bogus information from bd_get_diskinfo_std(). 556 */ 557 if (bd->bd_unit < 0x80) { 558 /* reset disk */ 559 bd_reset_disk(bd->bd_unit); 560 561 /* Get disk type */ 562 v86.ctl = V86_FLAGS; 563 v86.addr = 0x13; 564 v86.eax = 0x1500; 565 v86.edx = bd->bd_unit; 566 v86int(); 567 if (V86_CY(v86.efl) || (v86.eax & 0x300) == 0) 568 return (false); 569 } 570 571 ret = 1; 572 if (edd != 0) 573 ret = bd_get_diskinfo_ext(bd); 574 if (ret != 0 || bd->bd_sectors == 0) 575 ret = bd_get_diskinfo_std(bd); 576 577 if (ret != 0 && bd->bd_unit < 0x80) { 578 /* Set defaults for 1.44 floppy */ 579 bd->bd_cyl = 80; 580 bd->bd_hds = 2; 581 bd->bd_sec = 18; 582 bd->bd_sectors = 2880; 583 /* Since we are there, there most likely is no media */ 584 bd->bd_flags |= BD_NO_MEDIA; 585 ret = 0; 586 } 587 588 if (ret != 0) { 589 /* CD is special case, bc_add() has its own fallback. */ 590 if ((bd->bd_flags & BD_CDROM) != 0) 591 return (true); 592 593 if (bd->bd_sectors != 0 && edd != 0) { 594 bd->bd_sec = 63; 595 bd->bd_hds = 255; 596 bd->bd_cyl = 597 (bd->bd_sectors + bd->bd_sec * bd->bd_hds - 1) / 598 bd->bd_sec * bd->bd_hds; 599 } else { 600 const char *dv_name; 601 602 if ((bd->bd_flags & BD_FLOPPY) != 0) 603 dv_name = biosfd.dv_name; 604 else if ((bd->bd_flags & BD_CDROM) != 0) 605 dv_name = bioscd.dv_name; 606 else 607 dv_name = bioshd.dv_name; 608 609 printf("Can not get information about %s unit %#x\n", 610 dv_name, bd->bd_unit); 611 return (false); 612 } 613 } 614 615 if (bd->bd_sec == 0) 616 bd->bd_sec = 63; 617 if (bd->bd_hds == 0) 618 bd->bd_hds = 255; 619 620 if (bd->bd_sectors == 0) 621 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 622 623 DPRINTF("unit 0x%x geometry %d/%d/%d\n", bd->bd_unit, bd->bd_cyl, 624 bd->bd_hds, bd->bd_sec); 625 626 return (true); 627 } 628 629 static int 630 bd_count(bdinfo_list_t *bdi) 631 { 632 bdinfo_t *bd; 633 int i; 634 635 i = 0; 636 STAILQ_FOREACH(bd, bdi, bd_link) 637 i++; 638 return (i); 639 } 640 641 /* 642 * Print information about disks 643 */ 644 static int 645 bd_print_common(struct devsw *dev, bdinfo_list_t *bdi, int verbose) 646 { 647 char line[80]; 648 struct disk_devdesc devd; 649 bdinfo_t *bd; 650 int i, ret = 0; 651 char drive; 652 653 if (STAILQ_EMPTY(bdi)) 654 return (0); 655 656 printf("%s devices:", dev->dv_name); 657 if ((ret = pager_output("\n")) != 0) 658 return (ret); 659 660 i = -1; 661 STAILQ_FOREACH(bd, bdi, bd_link) { 662 i++; 663 664 switch (dev->dv_type) { 665 case DEVT_FD: 666 drive = 'A'; 667 break; 668 case DEVT_CD: 669 drive = 'C' + bd_count(&hdinfo); 670 break; 671 default: 672 drive = 'C'; 673 break; 674 } 675 676 snprintf(line, sizeof(line), 677 " %s%d: BIOS drive %c (%s%ju X %u):\n", 678 dev->dv_name, i, drive + i, 679 (bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA ? 680 "no media, " : "", 681 (uintmax_t)bd->bd_sectors, 682 bd->bd_sectorsize); 683 if ((ret = pager_output(line)) != 0) 684 break; 685 686 if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 687 continue; 688 689 if (dev->dv_type != DEVT_DISK) 690 continue; 691 692 devd.dd.d_dev = dev; 693 devd.dd.d_unit = i; 694 devd.d_slice = D_SLICENONE; 695 devd.d_partition = D_PARTNONE; 696 if (disk_open(&devd, 697 bd->bd_sectorsize * bd->bd_sectors, 698 bd->bd_sectorsize) == 0) { 699 snprintf(line, sizeof(line), " %s%d", 700 dev->dv_name, i); 701 ret = disk_print(&devd, line, verbose); 702 disk_close(&devd); 703 if (ret != 0) 704 break; 705 } 706 } 707 return (ret); 708 } 709 710 static int 711 fd_print(int verbose) 712 { 713 return (bd_print_common(&biosfd, &fdinfo, verbose)); 714 } 715 716 static int 717 bd_print(int verbose) 718 { 719 return (bd_print_common(&bioshd, &hdinfo, verbose)); 720 } 721 722 static int 723 cd_print(int verbose) 724 { 725 return (bd_print_common(&bioscd, &cdinfo, verbose)); 726 } 727 728 /* 729 * Read disk size from partition. 730 * This is needed to work around buggy BIOS systems returning 731 * wrong (truncated) disk media size. 732 * During bd_probe() we tested if the multiplication of bd_sectors 733 * would overflow so it should be safe to perform here. 734 */ 735 static uint64_t 736 bd_disk_get_sectors(struct disk_devdesc *dev) 737 { 738 bdinfo_t *bd; 739 struct disk_devdesc disk; 740 uint64_t size; 741 742 bd = bd_get_bdinfo(&dev->dd); 743 if (bd == NULL) 744 return (0); 745 746 disk.dd.d_dev = dev->dd.d_dev; 747 disk.dd.d_unit = dev->dd.d_unit; 748 disk.d_slice = D_SLICENONE; 749 disk.d_partition = D_PARTNONE; 750 disk.d_offset = 0; 751 752 size = bd->bd_sectors * bd->bd_sectorsize; 753 if (disk_open(&disk, size, bd->bd_sectorsize) == 0) { 754 (void) disk_ioctl(&disk, DIOCGMEDIASIZE, &size); 755 disk_close(&disk); 756 } 757 return (size / bd->bd_sectorsize); 758 } 759 760 /* 761 * Attempt to open the disk described by (dev) for use by (f). 762 * 763 * Note that the philosophy here is "give them exactly what 764 * they ask for". This is necessary because being too "smart" 765 * about what the user might want leads to complications. 766 * (eg. given no slice or partition value, with a disk that is 767 * sliced - are they after the first BSD slice, or the DOS 768 * slice before it?) 769 */ 770 static int 771 bd_open(struct open_file *f, ...) 772 { 773 bdinfo_t *bd; 774 struct disk_devdesc *dev; 775 va_list ap; 776 int rc; 777 778 va_start(ap, f); 779 dev = va_arg(ap, struct disk_devdesc *); 780 va_end(ap); 781 782 bd = bd_get_bdinfo(&dev->dd); 783 if (bd == NULL) 784 return (EIO); 785 786 if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) { 787 if (!bd_int13probe(bd)) 788 return (EIO); 789 if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 790 return (EIO); 791 } 792 if (bd->bd_bcache == NULL) 793 bd->bd_bcache = bcache_allocate(); 794 795 if (bd->bd_open == 0) 796 bd->bd_sectors = bd_disk_get_sectors(dev); 797 bd->bd_open++; 798 799 rc = 0; 800 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 801 rc = disk_open(dev, bd->bd_sectors * bd->bd_sectorsize, 802 bd->bd_sectorsize); 803 if (rc != 0) { 804 bd->bd_open--; 805 if (bd->bd_open == 0) { 806 bcache_free(bd->bd_bcache); 807 bd->bd_bcache = NULL; 808 } 809 } 810 } 811 return (rc); 812 } 813 814 static int 815 bd_close(struct open_file *f) 816 { 817 struct disk_devdesc *dev; 818 bdinfo_t *bd; 819 int rc = 0; 820 821 dev = (struct disk_devdesc *)f->f_devdata; 822 bd = bd_get_bdinfo(&dev->dd); 823 if (bd == NULL) 824 return (EIO); 825 826 bd->bd_open--; 827 if (bd->bd_open == 0) { 828 bcache_free(bd->bd_bcache); 829 bd->bd_bcache = NULL; 830 } 831 if (dev->dd.d_dev->dv_type == DEVT_DISK) 832 rc = disk_close(dev); 833 return (rc); 834 } 835 836 static int 837 bd_ioctl(struct open_file *f, u_long cmd, void *data) 838 { 839 bdinfo_t *bd; 840 struct disk_devdesc *dev; 841 int rc; 842 843 dev = (struct disk_devdesc *)f->f_devdata; 844 bd = bd_get_bdinfo(&dev->dd); 845 if (bd == NULL) 846 return (EIO); 847 848 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 849 rc = disk_ioctl(dev, cmd, data); 850 if (rc != ENOTTY) 851 return (rc); 852 } 853 854 switch (cmd) { 855 case DIOCGSECTORSIZE: 856 *(uint32_t *)data = bd->bd_sectorsize; 857 break; 858 case DIOCGMEDIASIZE: 859 *(uint64_t *)data = bd->bd_sectors * bd->bd_sectorsize; 860 break; 861 default: 862 return (ENOTTY); 863 } 864 return (0); 865 } 866 867 static int 868 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, 869 char *buf, size_t *rsize) 870 { 871 bdinfo_t *bd; 872 struct bcache_devdata bcd; 873 struct disk_devdesc *dev; 874 daddr_t offset; 875 876 dev = (struct disk_devdesc *)devdata; 877 bd = bd_get_bdinfo(&dev->dd); 878 if (bd == NULL) 879 return (EINVAL); 880 881 bcd.dv_strategy = bd_realstrategy; 882 bcd.dv_devdata = devdata; 883 bcd.dv_cache = bd->bd_bcache; 884 885 offset = 0; 886 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 887 888 offset = dev->d_offset * bd->bd_sectorsize; 889 offset /= BIOSDISK_SECSIZE; 890 } 891 return (bcache_strategy(&bcd, rw, dblk + offset, size, 892 buf, rsize)); 893 } 894 895 static int 896 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, 897 char *buf, size_t *rsize) 898 { 899 struct disk_devdesc *dev = (struct disk_devdesc *)devdata; 900 bdinfo_t *bd; 901 uint64_t disk_blocks, offset, d_offset; 902 size_t blks, blkoff, bsize, bio_size, rest; 903 caddr_t bbuf = NULL; 904 int rc; 905 906 bd = bd_get_bdinfo(&dev->dd); 907 if (bd == NULL || (bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 908 return (EIO); 909 910 /* 911 * First make sure the IO size is a multiple of 512 bytes. While we do 912 * process partial reads below, the strategy mechanism is built 913 * assuming IO is a multiple of 512B blocks. If the request is not 914 * a multiple of 512B blocks, it has to be some sort of bug. 915 */ 916 if (size == 0 || (size % BIOSDISK_SECSIZE) != 0) { 917 printf("bd_strategy: %d bytes I/O not multiple of %d\n", 918 size, BIOSDISK_SECSIZE); 919 return (EIO); 920 } 921 922 DPRINTF("open_disk %p", dev); 923 924 offset = dblk * BIOSDISK_SECSIZE; 925 dblk = offset / bd->bd_sectorsize; 926 blkoff = offset % bd->bd_sectorsize; 927 928 /* 929 * Check the value of the size argument. We do have quite small 930 * heap (64MB), but we do not know good upper limit, so we check against 931 * INT_MAX here. This will also protect us against possible overflows 932 * while translating block count to bytes. 933 */ 934 if (size > INT_MAX) { 935 DPRINTF("too large I/O: %zu bytes", size); 936 return (EIO); 937 } 938 939 blks = size / bd->bd_sectorsize; 940 if (blks == 0 || (size % bd->bd_sectorsize) != 0) 941 blks++; 942 943 if (dblk > dblk + blks) 944 return (EIO); 945 946 if (rsize) 947 *rsize = 0; 948 949 /* 950 * Get disk blocks, this value is either for whole disk or for 951 * partition. 952 */ 953 d_offset = 0; 954 disk_blocks = 0; 955 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 956 if (disk_ioctl(dev, DIOCGMEDIASIZE, &disk_blocks) == 0) { 957 /* DIOCGMEDIASIZE does return bytes. */ 958 disk_blocks /= bd->bd_sectorsize; 959 } 960 d_offset = dev->d_offset; 961 } 962 if (disk_blocks == 0) 963 disk_blocks = bd->bd_sectors - d_offset; 964 965 /* Validate source block address. */ 966 if (dblk < d_offset || dblk >= d_offset + disk_blocks) 967 return (EIO); 968 969 /* 970 * Truncate if we are crossing disk or partition end. 971 */ 972 if (dblk + blks >= d_offset + disk_blocks) { 973 blks = d_offset + disk_blocks - dblk; 974 size = blks * bd->bd_sectorsize; 975 DPRINTF("short I/O %d", blks); 976 } 977 978 bio_size = min(BIO_BUFFER_SIZE, size); 979 while (bio_size > bd->bd_sectorsize) { 980 bbuf = bio_alloc(bio_size); 981 if (bbuf != NULL) 982 break; 983 bio_size -= bd->bd_sectorsize; 984 } 985 if (bbuf == NULL) { 986 bio_size = V86_IO_BUFFER_SIZE; 987 if (bio_size / bd->bd_sectorsize == 0) 988 panic("BUG: Real mode buffer is too small"); 989 990 /* Use alternate 4k buffer */ 991 bbuf = PTOV(V86_IO_BUFFER); 992 } 993 rest = size; 994 rc = 0; 995 while (blks > 0) { 996 int x = min(blks, bio_size / bd->bd_sectorsize); 997 998 switch (rw & F_MASK) { 999 case F_READ: 1000 DPRINTF("read %d from %lld to %p", x, dblk, buf); 1001 bsize = bd->bd_sectorsize * x - blkoff; 1002 if (rest < bsize) 1003 bsize = rest; 1004 1005 if ((rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD)) != 0) { 1006 rc = EIO; 1007 goto error; 1008 } 1009 1010 bcopy(bbuf + blkoff, buf, bsize); 1011 break; 1012 case F_WRITE : 1013 DPRINTF("write %d from %lld to %p", x, dblk, buf); 1014 if (blkoff != 0) { 1015 /* 1016 * We got offset to sector, read 1 sector to 1017 * bbuf. 1018 */ 1019 x = 1; 1020 bsize = bd->bd_sectorsize - blkoff; 1021 bsize = min(bsize, rest); 1022 rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD); 1023 } else if (rest < bd->bd_sectorsize) { 1024 /* 1025 * The remaining block is not full 1026 * sector. Read 1 sector to bbuf. 1027 */ 1028 x = 1; 1029 bsize = rest; 1030 rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD); 1031 } else { 1032 /* We can write full sector(s). */ 1033 bsize = bd->bd_sectorsize * x; 1034 } 1035 /* 1036 * Put your Data In, Put your Data out, 1037 * Put your Data In, and shake it all about 1038 */ 1039 bcopy(buf, bbuf + blkoff, bsize); 1040 if ((rc = bd_io(dev, bd, dblk, x, bbuf, BD_WR)) != 0) { 1041 rc = EIO; 1042 goto error; 1043 } 1044 1045 break; 1046 default: 1047 /* DO NOTHING */ 1048 rc = EROFS; 1049 goto error; 1050 } 1051 1052 blkoff = 0; 1053 buf += bsize; 1054 rest -= bsize; 1055 blks -= x; 1056 dblk += x; 1057 } 1058 1059 if (rsize != NULL) 1060 *rsize = size; 1061 error: 1062 if (bbuf != PTOV(V86_IO_BUFFER)) 1063 bio_free(bbuf, bio_size); 1064 return (rc); 1065 } 1066 1067 static int 1068 bd_edd_io(bdinfo_t *bd, daddr_t dblk, int blks, caddr_t dest, 1069 int dowrite) 1070 { 1071 static struct edd_packet packet; 1072 1073 packet.len = sizeof(struct edd_packet); 1074 packet.count = blks; 1075 packet.off = VTOPOFF(dest); 1076 packet.seg = VTOPSEG(dest); 1077 packet.lba = dblk; 1078 v86.ctl = V86_FLAGS; 1079 v86.addr = 0x13; 1080 /* Should we Write with verify ?? 0x4302 ? */ 1081 if (dowrite == BD_WR) 1082 v86.eax = 0x4300; 1083 else 1084 v86.eax = 0x4200; 1085 v86.edx = bd->bd_unit; 1086 v86.ds = VTOPSEG(&packet); 1087 v86.esi = VTOPOFF(&packet); 1088 v86int(); 1089 if (V86_CY(v86.efl)) 1090 return (v86.eax >> 8); 1091 return (0); 1092 } 1093 1094 static int 1095 bd_chs_io(bdinfo_t *bd, daddr_t dblk, int blks, caddr_t dest, 1096 int dowrite) 1097 { 1098 uint32_t x, bpc, cyl, hd, sec; 1099 1100 bpc = bd->bd_sec * bd->bd_hds; /* blocks per cylinder */ 1101 x = dblk; 1102 cyl = x / bpc; /* block # / blocks per cylinder */ 1103 x %= bpc; /* block offset into cylinder */ 1104 hd = x / bd->bd_sec; /* offset / blocks per track */ 1105 sec = x % bd->bd_sec; /* offset into track */ 1106 1107 /* correct sector number for 1-based BIOS numbering */ 1108 sec++; 1109 1110 if (cyl > 1023) { 1111 /* CHS doesn't support cylinders > 1023. */ 1112 return (1); 1113 } 1114 1115 v86.ctl = V86_FLAGS; 1116 v86.addr = 0x13; 1117 if (dowrite == BD_WR) 1118 v86.eax = 0x300 | blks; 1119 else 1120 v86.eax = 0x200 | blks; 1121 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec; 1122 v86.edx = (hd << 8) | bd->bd_unit; 1123 v86.es = VTOPSEG(dest); 1124 v86.ebx = VTOPOFF(dest); 1125 v86int(); 1126 if (V86_CY(v86.efl)) 1127 return (v86.eax >> 8); 1128 return (0); 1129 } 1130 1131 static void 1132 bd_io_workaround(bdinfo_t *bd) 1133 { 1134 uint8_t buf[8 * 1024]; 1135 1136 bd_edd_io(bd, 0xffffffff, 1, (caddr_t)buf, BD_RD); 1137 } 1138 1139 static int 1140 bd_io(struct disk_devdesc *dev, bdinfo_t *bd, daddr_t dblk, int blks, 1141 caddr_t dest, int dowrite) 1142 { 1143 int result, retry; 1144 1145 /* Just in case some idiot actually tries to read/write -1 blocks... */ 1146 if (blks < 0) 1147 return (-1); 1148 1149 /* 1150 * Workaround for a problem with some HP ProLiant BIOS failing to work 1151 * out the boot disk after installation. hrs and kuriyama discovered 1152 * this problem with an HP ProLiant DL320e Gen 8 with a 3TB HDD, and 1153 * discovered that an int13h call seems to cause a buffer overrun in 1154 * the bios. The problem is alleviated by doing an extra read before 1155 * the buggy read. It is not immediately known whether other models 1156 * are similarly affected. 1157 * Loop retrying the operation a couple of times. The BIOS 1158 * may also retry. 1159 */ 1160 if (dowrite == BD_RD && dblk >= 0x100000000) 1161 bd_io_workaround(bd); 1162 for (retry = 0; retry < 3; retry++) { 1163 if (bd->bd_flags & BD_MODEEDD) 1164 result = bd_edd_io(bd, dblk, blks, dest, dowrite); 1165 else 1166 result = bd_chs_io(bd, dblk, blks, dest, dowrite); 1167 1168 if (result == 0) { 1169 if (bd->bd_flags & BD_NO_MEDIA) 1170 bd->bd_flags &= ~BD_NO_MEDIA; 1171 break; 1172 } 1173 1174 bd_reset_disk(bd->bd_unit); 1175 1176 /* 1177 * Error codes: 1178 * 20h controller failure 1179 * 31h no media in drive (IBM/MS INT 13 extensions) 1180 * 80h no media in drive, VMWare (Fusion) 1181 * There is no reason to repeat the IO with errors above. 1182 */ 1183 if (result == 0x20 || result == 0x31 || result == 0x80) { 1184 bd->bd_flags |= BD_NO_MEDIA; 1185 break; 1186 } 1187 } 1188 1189 if (result != 0 && (bd->bd_flags & BD_NO_MEDIA) == 0) { 1190 if (dowrite == BD_WR) { 1191 printf("%s%d: Write %d sector(s) from %p (0x%x) " 1192 "to %lld: 0x%x\n", dev->dd.d_dev->dv_name, 1193 dev->dd.d_unit, blks, dest, VTOP(dest), dblk, 1194 result); 1195 } else { 1196 printf("%s%d: Read %d sector(s) from %lld to %p " 1197 "(0x%x): 0x%x\n", dev->dd.d_dev->dv_name, 1198 dev->dd.d_unit, blks, dblk, dest, VTOP(dest), 1199 result); 1200 } 1201 } 1202 1203 return (result); 1204 } 1205 1206 /* 1207 * Return the BIOS geometry of a given "fixed drive" in a format 1208 * suitable for the legacy bootinfo structure. Since the kernel is 1209 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we 1210 * prefer to get the information directly, rather than rely on being 1211 * able to put it together from information already maintained for 1212 * different purposes and for a probably different number of drives. 1213 * 1214 * For valid drives, the geometry is expected in the format (31..0) 1215 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are 1216 * indicated by returning the geometry of a "1.2M" PC-format floppy 1217 * disk. And, incidentally, what is returned is not the geometry as 1218 * such but the highest valid cylinder, head, and sector numbers. 1219 */ 1220 uint32_t 1221 bd_getbigeom(int bunit) 1222 { 1223 1224 v86.ctl = V86_FLAGS; 1225 v86.addr = 0x13; 1226 v86.eax = 0x800; 1227 v86.edx = 0x80 + bunit; 1228 v86int(); 1229 if (V86_CY(v86.efl)) 1230 return (0x4f010f); 1231 return (((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) | 1232 (v86.edx & 0xff00) | (v86.ecx & 0x3f)); 1233 } 1234 1235 /* 1236 * Return a suitable dev_t value for (dev). 1237 * 1238 * In the case where it looks like (dev) is a SCSI disk, we allow the number of 1239 * IDE disks to be specified in $num_ide_disks. There should be a Better Way. 1240 */ 1241 int 1242 bd_getdev(struct i386_devdesc *d) 1243 { 1244 struct disk_devdesc *dev; 1245 bdinfo_t *bd; 1246 int biosdev; 1247 int major; 1248 int rootdev; 1249 char *nip, *cp; 1250 int i, unit, slice, partition; 1251 1252 /* XXX: Assume partition 'a'. */ 1253 slice = 0; 1254 partition = 0; 1255 1256 dev = (struct disk_devdesc *)d; 1257 bd = bd_get_bdinfo(&dev->dd); 1258 if (bd == NULL) 1259 return (-1); 1260 1261 biosdev = bd_unit2bios(d); 1262 DPRINTF("unit %d BIOS device %d", dev->dd.d_unit, biosdev); 1263 if (biosdev == -1) /* not a BIOS device */ 1264 return (-1); 1265 1266 if (dev->dd.d_dev->dv_type == DEVT_DISK) { 1267 if (disk_open(dev, bd->bd_sectors * bd->bd_sectorsize, 1268 bd->bd_sectorsize) != 0) /* oops, not a viable device */ 1269 return (-1); 1270 else 1271 disk_close(dev); 1272 slice = dev->d_slice + 1; 1273 partition = dev->d_partition; 1274 } 1275 1276 if (biosdev < 0x80) { 1277 /* floppy (or emulated floppy) or ATAPI device */ 1278 if (bd->bd_type == DT_ATAPI) { 1279 /* is an ATAPI disk */ 1280 major = WFDMAJOR; 1281 } else { 1282 /* is a floppy disk */ 1283 major = FDMAJOR; 1284 } 1285 } else { 1286 /* assume an IDE disk */ 1287 major = WDMAJOR; 1288 } 1289 /* default root disk unit number */ 1290 unit = biosdev & 0x7f; 1291 1292 if (dev->dd.d_dev->dv_type == DEVT_CD) { 1293 /* 1294 * XXX: Need to examine device spec here to figure out if 1295 * SCSI or ATAPI. No idea on how to figure out device number. 1296 * All we can really pass to the kernel is what bus and device 1297 * on which bus we were booted from, which dev_t isn't well 1298 * suited to since those number don't match to unit numbers 1299 * very well. We may just need to engage in a hack where 1300 * we pass -C to the boot args if we are the boot device. 1301 */ 1302 major = ACDMAJOR; 1303 unit = 0; /* XXX */ 1304 } 1305 1306 /* XXX a better kludge to set the root disk unit number */ 1307 if ((nip = getenv("root_disk_unit")) != NULL) { 1308 i = strtol(nip, &cp, 0); 1309 /* check for parse error */ 1310 if ((cp != nip) && (*cp == 0)) 1311 unit = i; 1312 } 1313 1314 rootdev = MAKEBOOTDEV(major, slice, unit, partition); 1315 DPRINTF("dev is 0x%x\n", rootdev); 1316 return (rootdev); 1317 } 1318