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 <stand.h> 44 #include <machine/bootinfo.h> 45 #include <stdarg.h> 46 47 #include <bootstrap.h> 48 #include <btxv86.h> 49 #include <edd.h> 50 #include "disk.h" 51 #include "libi386.h" 52 53 #define BIOS_NUMDRIVES 0x475 54 #define BIOSDISK_SECSIZE 512 55 #define BUFSIZE (1 * BIOSDISK_SECSIZE) 56 57 #define DT_ATAPI 0x10 /* disk type for ATAPI floppies */ 58 #define WDMAJOR 0 /* major numbers for devices we frontend for */ 59 #define WFDMAJOR 1 60 #define FDMAJOR 2 61 #define DAMAJOR 4 62 63 #ifdef DISK_DEBUG 64 #define DEBUG(fmt, args...) printf("%s: " fmt "\n", __func__, ## args) 65 #else 66 #define DEBUG(fmt, args...) 67 #endif 68 69 /* 70 * List of BIOS devices, translation from disk unit number to 71 * BIOS unit number. 72 */ 73 static struct bdinfo 74 { 75 int bd_unit; /* BIOS unit number */ 76 int bd_cyl; /* BIOS geometry */ 77 int bd_hds; 78 int bd_sec; 79 int bd_flags; 80 #define BD_MODEINT13 0x0000 81 #define BD_MODEEDD1 0x0001 82 #define BD_MODEEDD3 0x0002 83 #define BD_MODEEDD (BD_MODEEDD1 | BD_MODEEDD3) 84 #define BD_MODEMASK 0x0003 85 #define BD_FLOPPY 0x0004 86 #define BD_NO_MEDIA 0x0008 87 int bd_type; /* BIOS 'drive type' (floppy only) */ 88 uint16_t bd_sectorsize; /* Sector size */ 89 uint64_t bd_sectors; /* Disk size */ 90 int bd_open; /* reference counter */ 91 void *bd_bcache; /* buffer cache data */ 92 } bdinfo [MAXBDDEV]; 93 static int nbdinfo = 0; 94 95 #define BD(dev) (bdinfo[(dev)->dd.d_unit]) 96 #define BD_RD 0 97 #define BD_WR 1 98 99 static void bd_io_workaround(struct disk_devdesc *dev); 100 101 static int bd_io(struct disk_devdesc *, daddr_t, int, caddr_t, int); 102 static int bd_int13probe(struct bdinfo *bd); 103 104 static int bd_init(void); 105 static int bd_strategy(void *devdata, int flag, daddr_t dblk, size_t size, 106 char *buf, size_t *rsize); 107 static int bd_realstrategy(void *devdata, int flag, daddr_t dblk, size_t size, 108 char *buf, size_t *rsize); 109 static int bd_open(struct open_file *f, ...); 110 static int bd_close(struct open_file *f); 111 static int bd_ioctl(struct open_file *f, u_long cmd, void *data); 112 static int bd_print(int verbose); 113 114 struct devsw biosdisk = { 115 "disk", 116 DEVT_DISK, 117 bd_init, 118 bd_strategy, 119 bd_open, 120 bd_close, 121 bd_ioctl, 122 bd_print, 123 NULL 124 }; 125 126 /* 127 * Translate between BIOS device numbers and our private unit numbers. 128 */ 129 int 130 bd_bios2unit(int biosdev) 131 { 132 int i; 133 134 DEBUG("looking for bios device 0x%x", biosdev); 135 for (i = 0; i < nbdinfo; i++) { 136 DEBUG("bd unit %d is BIOS device 0x%x", i, bdinfo[i].bd_unit); 137 if (bdinfo[i].bd_unit == biosdev) 138 return (i); 139 } 140 return (-1); 141 } 142 143 int 144 bd_unit2bios(int unit) 145 { 146 147 if ((unit >= 0) && (unit < nbdinfo)) 148 return (bdinfo[unit].bd_unit); 149 return (-1); 150 } 151 152 /* 153 * Quiz the BIOS for disk devices, save a little info about them. 154 */ 155 static int 156 bd_init(void) 157 { 158 int base, unit, nfd = 0; 159 160 /* sequence 0, 0x80 */ 161 for (base = 0; base <= 0x80; base += 0x80) { 162 for (unit = base; (nbdinfo < MAXBDDEV); unit++) { 163 #ifndef VIRTUALBOX 164 /* 165 * Check the BIOS equipment list for number 166 * of fixed disks. 167 */ 168 if (base == 0x80 && 169 (nfd >= *(unsigned char *)PTOV(BIOS_NUMDRIVES))) 170 break; 171 #endif 172 bdinfo[nbdinfo].bd_open = 0; 173 bdinfo[nbdinfo].bd_bcache = NULL; 174 bdinfo[nbdinfo].bd_unit = unit; 175 bdinfo[nbdinfo].bd_flags = unit < 0x80 ? BD_FLOPPY: 0; 176 if (!bd_int13probe(&bdinfo[nbdinfo])) 177 break; 178 179 /* XXX we need "disk aliases" to make this simpler */ 180 printf("BIOS drive %c: is disk%d\n", (unit < 0x80) ? 181 ('A' + unit): ('C' + unit - 0x80), nbdinfo); 182 nbdinfo++; 183 if (base == 0x80) 184 nfd++; 185 } 186 } 187 bcache_add_dev(nbdinfo); 188 return (0); 189 } 190 191 /* 192 * Return EDD version or 0 if EDD is not supported on this drive. 193 */ 194 static int 195 bd_check_extensions(int unit) 196 { 197 /* Determine if we can use EDD with this device. */ 198 v86.ctl = V86_FLAGS; 199 v86.addr = 0x13; 200 v86.eax = 0x4100; 201 v86.edx = unit; 202 v86.ebx = 0x55aa; 203 v86int(); 204 205 if (V86_CY(v86.efl) || /* carry set */ 206 (v86.ebx & 0xffff) != 0xaa55) /* signature */ 207 return (0); 208 209 /* extended disk access functions (AH=42h-44h,47h,48h) supported */ 210 if ((v86.ecx & EDD_INTERFACE_FIXED_DISK) == 0) 211 return (0); 212 213 return ((v86.eax >> 8) & 0xff); 214 } 215 216 static void 217 bd_reset_disk(int unit) 218 { 219 /* reset disk */ 220 v86.ctl = V86_FLAGS; 221 v86.addr = 0x13; 222 v86.eax = 0; 223 v86.edx = unit; 224 v86int(); 225 } 226 227 /* 228 * Read CHS info. Return 0 on success, error otherwise. 229 */ 230 static int 231 bd_get_diskinfo_std(struct bdinfo *bd) 232 { 233 bzero(&v86, sizeof(v86)); 234 v86.ctl = V86_FLAGS; 235 v86.addr = 0x13; 236 v86.eax = 0x800; 237 v86.edx = bd->bd_unit; 238 v86int(); 239 240 if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0)) 241 return ((v86.eax & 0xff00) >> 8); 242 243 /* return custom error on absurd sector number */ 244 if ((v86.ecx & 0x3f) == 0) 245 return (0x60); 246 247 bd->bd_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1; 248 /* Convert max head # -> # of heads */ 249 bd->bd_hds = ((v86.edx & 0xff00) >> 8) + 1; 250 bd->bd_sec = v86.ecx & 0x3f; 251 bd->bd_type = v86.ebx; 252 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 253 254 return (0); 255 } 256 257 /* 258 * Read EDD info. Return 0 on success, error otherwise. 259 */ 260 static int 261 bd_get_diskinfo_ext(struct bdinfo *bd) 262 { 263 struct edd_params params; 264 uint64_t total; 265 266 /* Get disk params */ 267 bzero(¶ms, sizeof(params)); 268 params.len = sizeof(params); 269 v86.ctl = V86_FLAGS; 270 v86.addr = 0x13; 271 v86.eax = 0x4800; 272 v86.edx = bd->bd_unit; 273 v86.ds = VTOPSEG(¶ms); 274 v86.esi = VTOPOFF(¶ms); 275 v86int(); 276 277 if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0)) 278 return ((v86.eax & 0xff00) >> 8); 279 280 /* 281 * Sector size must be a multiple of 512 bytes. 282 * An alternate test would be to check power of 2, 283 * powerof2(params.sector_size). 284 * 4K is largest read buffer we can use at this time. 285 */ 286 if (params.sector_size >= 512 && 287 params.sector_size <= 4096 && 288 (params.sector_size % BIOSDISK_SECSIZE) == 0) 289 bd->bd_sectorsize = params.sector_size; 290 291 bd->bd_cyl = params.cylinders; 292 bd->bd_hds = params.heads; 293 bd->bd_sec = params.sectors_per_track; 294 295 if (params.sectors != 0) { 296 total = params.sectors; 297 } else { 298 total = (uint64_t)params.cylinders * 299 params.heads * params.sectors_per_track; 300 } 301 bd->bd_sectors = total; 302 303 return (0); 304 } 305 306 /* 307 * Try to detect a device supported by the legacy int13 BIOS 308 */ 309 static int 310 bd_int13probe(struct bdinfo *bd) 311 { 312 int edd; 313 int ret; 314 315 bd->bd_flags &= ~BD_NO_MEDIA; 316 317 edd = bd_check_extensions(bd->bd_unit); 318 if (edd == 0) 319 bd->bd_flags |= BD_MODEINT13; 320 else if (edd < 0x30) 321 bd->bd_flags |= BD_MODEEDD1; 322 else 323 bd->bd_flags |= BD_MODEEDD3; 324 325 /* Default sector size */ 326 bd->bd_sectorsize = BIOSDISK_SECSIZE; 327 328 /* 329 * Test if the floppy device is present, so we can avoid receiving 330 * bogus information from bd_get_diskinfo_std(). 331 */ 332 if (bd->bd_unit < 0x80) { 333 /* reset disk */ 334 bd_reset_disk(bd->bd_unit); 335 336 /* Get disk type */ 337 v86.ctl = V86_FLAGS; 338 v86.addr = 0x13; 339 v86.eax = 0x1500; 340 v86.edx = bd->bd_unit; 341 v86int(); 342 if (V86_CY(v86.efl) || (v86.eax & 0x300) == 0) 343 return (0); 344 } 345 346 ret = 1; 347 if (edd != 0) 348 ret = bd_get_diskinfo_ext(bd); 349 if (ret != 0 || bd->bd_sectors == 0) 350 ret = bd_get_diskinfo_std(bd); 351 352 if (ret != 0 && bd->bd_unit < 0x80) { 353 /* Set defaults for 1.44 floppy */ 354 bd->bd_cyl = 80; 355 bd->bd_hds = 2; 356 bd->bd_sec = 18; 357 bd->bd_type = 4; 358 bd->bd_sectors = 2880; 359 /* Since we are there, there most likely is no media */ 360 bd->bd_flags |= BD_NO_MEDIA; 361 ret = 0; 362 } 363 364 if (ret != 0) { 365 if (bd->bd_sectors != 0 && edd != 0) { 366 bd->bd_sec = 63; 367 bd->bd_hds = 255; 368 bd->bd_cyl = 369 (bd->bd_sectors + bd->bd_sec * bd->bd_hds - 1) / 370 bd->bd_sec * bd->bd_hds; 371 } else { 372 printf("Can not get information about %s unit %#x\n", 373 biosdisk.dv_name, bd->bd_unit); 374 return (0); 375 } 376 } 377 378 if (bd->bd_sec == 0) 379 bd->bd_sec = 63; 380 if (bd->bd_hds == 0) 381 bd->bd_hds = 255; 382 383 if (bd->bd_sectors == 0) 384 bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec; 385 386 DEBUG("unit 0x%x geometry %d/%d/%d", bd->bd_unit, bd->bd_cyl, 387 bd->bd_hds, bd->bd_sec); 388 389 return (1); 390 } 391 392 /* 393 * Print information about disks 394 */ 395 static int 396 bd_print(int verbose) 397 { 398 static char line[80]; 399 struct disk_devdesc dev; 400 int i, ret = 0; 401 402 if (nbdinfo == 0) 403 return (0); 404 405 printf("%s devices:", biosdisk.dv_name); 406 if ((ret = pager_output("\n")) != 0) 407 return (ret); 408 409 for (i = 0; i < nbdinfo; i++) { 410 snprintf(line, sizeof(line), 411 " disk%d: BIOS drive %c (%s%ju X %u):\n", i, 412 (bdinfo[i].bd_unit < 0x80) ? ('A' + bdinfo[i].bd_unit): 413 ('C' + bdinfo[i].bd_unit - 0x80), 414 (bdinfo[i].bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA ? 415 "no media, " : "", 416 (uintmax_t)bdinfo[i].bd_sectors, 417 bdinfo[i].bd_sectorsize); 418 if ((ret = pager_output(line)) != 0) 419 break; 420 421 if ((bdinfo[i].bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 422 continue; 423 424 dev.dd.d_dev = &biosdisk; 425 dev.dd.d_unit = i; 426 dev.d_slice = -1; 427 dev.d_partition = -1; 428 if (disk_open(&dev, 429 bdinfo[i].bd_sectorsize * bdinfo[i].bd_sectors, 430 bdinfo[i].bd_sectorsize) == 0) { 431 snprintf(line, sizeof(line), " disk%d", i); 432 ret = disk_print(&dev, line, verbose); 433 disk_close(&dev); 434 if (ret != 0) 435 break; 436 } 437 } 438 return (ret); 439 } 440 441 /* 442 * Attempt to open the disk described by (dev) for use by (f). 443 * 444 * Note that the philosophy here is "give them exactly what 445 * they ask for". This is necessary because being too "smart" 446 * about what the user might want leads to complications. 447 * (eg. given no slice or partition value, with a disk that is 448 * sliced - are they after the first BSD slice, or the DOS 449 * slice before it?) 450 */ 451 static int 452 bd_open(struct open_file *f, ...) 453 { 454 struct disk_devdesc *dev; 455 struct disk_devdesc disk; 456 va_list ap; 457 uint64_t size; 458 int rc; 459 460 va_start(ap, f); 461 dev = va_arg(ap, struct disk_devdesc *); 462 va_end(ap); 463 464 if (dev->dd.d_unit < 0 || dev->dd.d_unit >= nbdinfo) 465 return (EIO); 466 467 if ((BD(dev).bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) { 468 if (!bd_int13probe(&BD(dev))) 469 return (EIO); 470 if ((BD(dev).bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 471 return (EIO); 472 } 473 BD(dev).bd_open++; 474 if (BD(dev).bd_bcache == NULL) 475 BD(dev).bd_bcache = bcache_allocate(); 476 477 /* 478 * Read disk size from partition. 479 * This is needed to work around buggy BIOS systems returning 480 * wrong (truncated) disk media size. 481 * During bd_probe() we tested if the mulitplication of bd_sectors 482 * would overflow so it should be safe to perform here. 483 */ 484 disk.dd.d_dev = dev->dd.d_dev; 485 disk.dd.d_unit = dev->dd.d_unit; 486 disk.d_slice = -1; 487 disk.d_partition = -1; 488 disk.d_offset = 0; 489 490 if (disk_open(&disk, BD(dev).bd_sectors * BD(dev).bd_sectorsize, 491 BD(dev).bd_sectorsize) == 0) { 492 493 if (disk_ioctl(&disk, DIOCGMEDIASIZE, &size) == 0) { 494 size /= BD(dev).bd_sectorsize; 495 if (size > BD(dev).bd_sectors) 496 BD(dev).bd_sectors = size; 497 } 498 disk_close(&disk); 499 } 500 501 rc = disk_open(dev, BD(dev).bd_sectors * BD(dev).bd_sectorsize, 502 BD(dev).bd_sectorsize); 503 if (rc != 0) { 504 BD(dev).bd_open--; 505 if (BD(dev).bd_open == 0) { 506 bcache_free(BD(dev).bd_bcache); 507 BD(dev).bd_bcache = NULL; 508 } 509 } 510 return (rc); 511 } 512 513 static int 514 bd_close(struct open_file *f) 515 { 516 struct disk_devdesc *dev; 517 518 dev = (struct disk_devdesc *)f->f_devdata; 519 BD(dev).bd_open--; 520 if (BD(dev).bd_open == 0) { 521 bcache_free(BD(dev).bd_bcache); 522 BD(dev).bd_bcache = NULL; 523 } 524 return (disk_close(dev)); 525 } 526 527 static int 528 bd_ioctl(struct open_file *f, u_long cmd, void *data) 529 { 530 struct disk_devdesc *dev; 531 int rc; 532 533 dev = (struct disk_devdesc *)f->f_devdata; 534 535 rc = disk_ioctl(dev, cmd, data); 536 if (rc != ENOTTY) 537 return (rc); 538 539 switch (cmd) { 540 case DIOCGSECTORSIZE: 541 *(uint32_t *)data = BD(dev).bd_sectorsize; 542 break; 543 case DIOCGMEDIASIZE: 544 *(uint64_t *)data = BD(dev).bd_sectors * BD(dev).bd_sectorsize; 545 break; 546 default: 547 return (ENOTTY); 548 } 549 return (0); 550 } 551 552 static int 553 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, 554 char *buf, size_t *rsize) 555 { 556 struct bcache_devdata bcd; 557 struct disk_devdesc *dev; 558 559 dev = (struct disk_devdesc *)devdata; 560 bcd.dv_strategy = bd_realstrategy; 561 bcd.dv_devdata = devdata; 562 bcd.dv_cache = BD(dev).bd_bcache; 563 return (bcache_strategy(&bcd, rw, dblk + dev->d_offset, size, 564 buf, rsize)); 565 } 566 567 static int 568 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, 569 char *buf, size_t *rsize) 570 { 571 struct disk_devdesc *dev = (struct disk_devdesc *)devdata; 572 uint64_t disk_blocks, offset; 573 size_t blks, blkoff, bsize, rest; 574 caddr_t bbuf; 575 int rc; 576 577 if ((BD(dev).bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) 578 return (EIO); 579 580 /* 581 * First make sure the IO size is a multiple of 512 bytes. While we do 582 * process partial reads below, the strategy mechanism is built 583 * assuming IO is a multiple of 512B blocks. If the request is not 584 * a multiple of 512B blocks, it has to be some sort of bug. 585 */ 586 if (size == 0 || (size % BIOSDISK_SECSIZE) != 0) { 587 printf("bd_strategy: %d bytes I/O not multiple of %d\n", 588 size, BIOSDISK_SECSIZE); 589 return (EIO); 590 } 591 592 DEBUG("open_disk %p", dev); 593 594 offset = dblk * BIOSDISK_SECSIZE; 595 dblk = offset / BD(dev).bd_sectorsize; 596 blkoff = offset % BD(dev).bd_sectorsize; 597 598 /* 599 * Check the value of the size argument. We do have quite small 600 * heap (64MB), but we do not know good upper limit, so we check against 601 * INT_MAX here. This will also protect us against possible overflows 602 * while translating block count to bytes. 603 */ 604 if (size > INT_MAX) { 605 DEBUG("too large I/O: %zu bytes", size); 606 return (EIO); 607 } 608 609 blks = size / BD(dev).bd_sectorsize; 610 if (blks == 0 || (size % BD(dev).bd_sectorsize) != 0) 611 blks++; 612 613 if (dblk > dblk + blks) 614 return (EIO); 615 616 if (rsize) 617 *rsize = 0; 618 619 /* 620 * Get disk blocks, this value is either for whole disk or for 621 * partition. 622 */ 623 if (disk_ioctl(dev, DIOCGMEDIASIZE, &disk_blocks) == 0) { 624 /* DIOCGMEDIASIZE does return bytes. */ 625 disk_blocks /= BD(dev).bd_sectorsize; 626 } else { 627 /* We should not get here. Just try to survive. */ 628 disk_blocks = BD(dev).bd_sectors - dev->d_offset; 629 } 630 631 /* Validate source block address. */ 632 if (dblk < dev->d_offset || dblk >= dev->d_offset + disk_blocks) 633 return (EIO); 634 635 /* 636 * Truncate if we are crossing disk or partition end. 637 */ 638 if (dblk + blks >= dev->d_offset + disk_blocks) { 639 blks = dev->d_offset + disk_blocks - dblk; 640 size = blks * BD(dev).bd_sectorsize; 641 DEBUG("short I/O %d", blks); 642 } 643 644 if (V86_IO_BUFFER_SIZE / BD(dev).bd_sectorsize == 0) 645 panic("BUG: Real mode buffer is too small\n"); 646 647 bbuf = PTOV(V86_IO_BUFFER); 648 rest = size; 649 650 while (blks > 0) { 651 int x = min(blks, V86_IO_BUFFER_SIZE / BD(dev).bd_sectorsize); 652 653 switch (rw & F_MASK) { 654 case F_READ: 655 DEBUG("read %d from %lld to %p", x, dblk, buf); 656 bsize = BD(dev).bd_sectorsize * x - blkoff; 657 if (rest < bsize) 658 bsize = rest; 659 660 if ((rc = bd_io(dev, dblk, x, bbuf, BD_RD)) != 0) 661 return (EIO); 662 663 bcopy(bbuf + blkoff, buf, bsize); 664 break; 665 case F_WRITE : 666 DEBUG("write %d from %lld to %p", x, dblk, buf); 667 if (blkoff != 0) { 668 /* 669 * We got offset to sector, read 1 sector to 670 * bbuf. 671 */ 672 x = 1; 673 bsize = BD(dev).bd_sectorsize - blkoff; 674 bsize = min(bsize, rest); 675 rc = bd_io(dev, dblk, x, bbuf, BD_RD); 676 } else if (rest < BD(dev).bd_sectorsize) { 677 /* 678 * The remaining block is not full 679 * sector. Read 1 sector to bbuf. 680 */ 681 x = 1; 682 bsize = rest; 683 rc = bd_io(dev, dblk, x, bbuf, BD_RD); 684 } else { 685 /* We can write full sector(s). */ 686 bsize = BD(dev).bd_sectorsize * x; 687 } 688 /* 689 * Put your Data In, Put your Data out, 690 * Put your Data In, and shake it all about 691 */ 692 bcopy(buf, bbuf + blkoff, bsize); 693 if ((rc = bd_io(dev, dblk, x, bbuf, BD_WR)) != 0) 694 return (EIO); 695 696 break; 697 default: 698 /* DO NOTHING */ 699 return (EROFS); 700 } 701 702 blkoff = 0; 703 buf += bsize; 704 rest -= bsize; 705 blks -= x; 706 dblk += x; 707 } 708 709 if (rsize != NULL) 710 *rsize = size; 711 return (0); 712 } 713 714 static int 715 bd_edd_io(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest, 716 int dowrite) 717 { 718 static struct edd_packet packet; 719 720 packet.len = sizeof(struct edd_packet); 721 packet.count = blks; 722 packet.off = VTOPOFF(dest); 723 packet.seg = VTOPSEG(dest); 724 packet.lba = dblk; 725 v86.ctl = V86_FLAGS; 726 v86.addr = 0x13; 727 /* Should we Write with verify ?? 0x4302 ? */ 728 if (dowrite == BD_WR) 729 v86.eax = 0x4300; 730 else 731 v86.eax = 0x4200; 732 v86.edx = BD(dev).bd_unit; 733 v86.ds = VTOPSEG(&packet); 734 v86.esi = VTOPOFF(&packet); 735 v86int(); 736 if (V86_CY(v86.efl)) 737 return (v86.eax >> 8); 738 return (0); 739 } 740 741 static int 742 bd_chs_io(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest, 743 int dowrite) 744 { 745 uint32_t x, bpc, cyl, hd, sec; 746 747 bpc = BD(dev).bd_sec * BD(dev).bd_hds; /* blocks per cylinder */ 748 x = dblk; 749 cyl = x / bpc; /* block # / blocks per cylinder */ 750 x %= bpc; /* block offset into cylinder */ 751 hd = x / BD(dev).bd_sec; /* offset / blocks per track */ 752 sec = x % BD(dev).bd_sec; /* offset into track */ 753 754 /* correct sector number for 1-based BIOS numbering */ 755 sec++; 756 757 if (cyl > 1023) { 758 /* CHS doesn't support cylinders > 1023. */ 759 return (1); 760 } 761 762 v86.ctl = V86_FLAGS; 763 v86.addr = 0x13; 764 if (dowrite == BD_WR) 765 v86.eax = 0x300 | blks; 766 else 767 v86.eax = 0x200 | blks; 768 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec; 769 v86.edx = (hd << 8) | BD(dev).bd_unit; 770 v86.es = VTOPSEG(dest); 771 v86.ebx = VTOPOFF(dest); 772 v86int(); 773 if (V86_CY(v86.efl)) 774 return (v86.eax >> 8); 775 return (0); 776 } 777 778 static void 779 bd_io_workaround(struct disk_devdesc *dev) 780 { 781 uint8_t buf[8 * 1024]; 782 783 bd_edd_io(dev, 0xffffffff, 1, (caddr_t)buf, BD_RD); 784 } 785 786 static int 787 bd_io(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest, 788 int dowrite) 789 { 790 int result, retry; 791 792 /* Just in case some idiot actually tries to read/write -1 blocks... */ 793 if (blks < 0) 794 return (-1); 795 796 /* 797 * Workaround for a problem with some HP ProLiant BIOS failing to work 798 * out the boot disk after installation. hrs and kuriyama discovered 799 * this problem with an HP ProLiant DL320e Gen 8 with a 3TB HDD, and 800 * discovered that an int13h call seems to cause a buffer overrun in 801 * the bios. The problem is alleviated by doing an extra read before 802 * the buggy read. It is not immediately known whether other models 803 * are similarly affected. 804 * Loop retrying the operation a couple of times. The BIOS 805 * may also retry. 806 */ 807 if (dowrite == BD_RD && dblk >= 0x100000000) 808 bd_io_workaround(dev); 809 for (retry = 0; retry < 3; retry++) { 810 if (BD(dev).bd_flags & BD_MODEEDD) 811 result = bd_edd_io(dev, dblk, blks, dest, dowrite); 812 else 813 result = bd_chs_io(dev, dblk, blks, dest, dowrite); 814 815 if (result == 0) { 816 if (BD(dev).bd_flags & BD_NO_MEDIA) 817 BD(dev).bd_flags &= ~BD_NO_MEDIA; 818 break; 819 } 820 821 bd_reset_disk(BD(dev).bd_unit); 822 823 /* 824 * Error codes: 825 * 20h controller failure 826 * 31h no media in drive (IBM/MS INT 13 extensions) 827 * 80h no media in drive, VMWare (Fusion) 828 * There is no reason to repeat the IO with errors above. 829 */ 830 if (result == 0x20 || result == 0x31 || result == 0x80) { 831 BD(dev).bd_flags |= BD_NO_MEDIA; 832 break; 833 } 834 } 835 836 if (result != 0 && (BD(dev).bd_flags & BD_NO_MEDIA) == 0) { 837 if (dowrite == BD_WR) { 838 printf("%s%d: Write %d sector(s) from %p (0x%x) " 839 "to %lld: 0x%x\n", dev->dd.d_dev->dv_name, 840 dev->dd.d_unit, blks, dest, VTOP(dest), dblk, 841 result); 842 } else { 843 printf("%s%d: Read %d sector(s) from %lld to %p " 844 "(0x%x): 0x%x\n", dev->dd.d_dev->dv_name, 845 dev->dd.d_unit, blks, dblk, dest, VTOP(dest), 846 result); 847 } 848 } 849 850 return (result); 851 } 852 853 /* 854 * Return the BIOS geometry of a given "fixed drive" in a format 855 * suitable for the legacy bootinfo structure. Since the kernel is 856 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we 857 * prefer to get the information directly, rather than rely on being 858 * able to put it together from information already maintained for 859 * different purposes and for a probably different number of drives. 860 * 861 * For valid drives, the geometry is expected in the format (31..0) 862 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are 863 * indicated by returning the geometry of a "1.2M" PC-format floppy 864 * disk. And, incidentally, what is returned is not the geometry as 865 * such but the highest valid cylinder, head, and sector numbers. 866 */ 867 uint32_t 868 bd_getbigeom(int bunit) 869 { 870 871 v86.ctl = V86_FLAGS; 872 v86.addr = 0x13; 873 v86.eax = 0x800; 874 v86.edx = 0x80 + bunit; 875 v86int(); 876 if (V86_CY(v86.efl)) 877 return (0x4f010f); 878 return (((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) | 879 (v86.edx & 0xff00) | (v86.ecx & 0x3f)); 880 } 881 882 /* 883 * Return a suitable dev_t value for (dev). 884 * 885 * In the case where it looks like (dev) is a SCSI disk, we allow the number of 886 * IDE disks to be specified in $num_ide_disks. There should be a Better Way. 887 */ 888 int 889 bd_getdev(struct i386_devdesc *d) 890 { 891 struct disk_devdesc *dev; 892 int biosdev; 893 int major; 894 int rootdev; 895 char *nip, *cp; 896 int i, unit; 897 898 dev = (struct disk_devdesc *)d; 899 biosdev = bd_unit2bios(dev->dd.d_unit); 900 DEBUG("unit %d BIOS device %d", dev->dd.d_unit, biosdev); 901 if (biosdev == -1) /* not a BIOS device */ 902 return (-1); 903 if (disk_open(dev, BD(dev).bd_sectors * BD(dev).bd_sectorsize, 904 BD(dev).bd_sectorsize) != 0) /* oops, not a viable device */ 905 return (-1); 906 else 907 disk_close(dev); 908 909 if (biosdev < 0x80) { 910 /* floppy (or emulated floppy) or ATAPI device */ 911 if (bdinfo[dev->dd.d_unit].bd_type == DT_ATAPI) { 912 /* is an ATAPI disk */ 913 major = WFDMAJOR; 914 } else { 915 /* is a floppy disk */ 916 major = FDMAJOR; 917 } 918 } else { 919 /* assume an IDE disk */ 920 major = WDMAJOR; 921 } 922 /* default root disk unit number */ 923 unit = biosdev & 0x7f; 924 925 /* XXX a better kludge to set the root disk unit number */ 926 if ((nip = getenv("root_disk_unit")) != NULL) { 927 i = strtol(nip, &cp, 0); 928 /* check for parse error */ 929 if ((cp != nip) && (*cp == 0)) 930 unit = i; 931 } 932 933 rootdev = MAKEBOOTDEV(major, dev->d_slice + 1, unit, dev->d_partition); 934 DEBUG("dev is 0x%x\n", rootdev); 935 return (rootdev); 936 } 937