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 30 /* 31 * BIOS disk device handling. 32 * 33 * Ideas and algorithms from: 34 * 35 * - NetBSD libi386/biosdisk.c 36 * - FreeBSD biosboot/disk.c 37 * 38 */ 39 40 #include <sys/disk.h> 41 #include <sys/limits.h> 42 #include <stand.h> 43 #include <machine/bootinfo.h> 44 #include <stdarg.h> 45 46 #include <bootstrap.h> 47 #include <btxv86.h> 48 #include <edd.h> 49 #include "disk.h" 50 #include "libi386.h" 51 52 CTASSERT(sizeof(struct i386_devdesc) >= sizeof(struct disk_devdesc)); 53 54 #define BIOS_NUMDRIVES 0x475 55 #define BIOSDISK_SECSIZE 512 56 #define BUFSIZE (1 * BIOSDISK_SECSIZE) 57 58 #define DT_ATAPI 0x10 /* disk type for ATAPI floppies */ 59 #define WDMAJOR 0 /* major numbers for devices we frontend for */ 60 #define WFDMAJOR 1 61 #define FDMAJOR 2 62 #define DAMAJOR 4 63 64 #ifdef DISK_DEBUG 65 # define DEBUG(fmt, args...) printf("%s: " fmt "\n" , __func__ , ## args) 66 #else 67 # define DEBUG(fmt, args...) 68 #endif 69 70 /* 71 * List of BIOS devices, translation from disk unit number to 72 * BIOS unit number. 73 */ 74 static struct bdinfo 75 { 76 int bd_unit; /* BIOS unit number */ 77 int bd_cyl; /* BIOS geometry */ 78 int bd_hds; 79 int bd_sec; 80 int bd_flags; 81 #define BD_MODEINT13 0x0000 82 #define BD_MODEEDD1 0x0001 83 #define BD_MODEEDD3 0x0002 84 #define BD_MODEMASK 0x0003 85 #define BD_FLOPPY 0x0004 86 int bd_type; /* BIOS 'drive type' (floppy only) */ 87 uint16_t bd_sectorsize; /* Sector size */ 88 uint64_t bd_sectors; /* Disk size */ 89 int bd_open; /* reference counter */ 90 void *bd_bcache; /* buffer cache data */ 91 } bdinfo [MAXBDDEV]; 92 static int nbdinfo = 0; 93 94 #define BD(dev) (bdinfo[(dev)->d_unit]) 95 96 static int bd_io(struct disk_devdesc *, daddr_t, int, caddr_t, int); 97 static int bd_int13probe(struct bdinfo *bd); 98 99 static int bd_init(void); 100 static int bd_strategy(void *devdata, int flag, daddr_t dblk, size_t size, 101 char *buf, size_t *rsize); 102 static int bd_realstrategy(void *devdata, int flag, daddr_t dblk, size_t size, 103 char *buf, size_t *rsize); 104 static int bd_open(struct open_file *f, ...); 105 static int bd_close(struct open_file *f); 106 static int bd_ioctl(struct open_file *f, u_long cmd, void *data); 107 static int bd_print(int verbose); 108 109 struct devsw biosdisk = { 110 "disk", 111 DEVT_DISK, 112 bd_init, 113 bd_strategy, 114 bd_open, 115 bd_close, 116 bd_ioctl, 117 bd_print, 118 NULL 119 }; 120 121 /* 122 * Translate between BIOS device numbers and our private unit numbers. 123 */ 124 int 125 bd_bios2unit(int biosdev) 126 { 127 int i; 128 129 DEBUG("looking for bios device 0x%x", biosdev); 130 for (i = 0; i < nbdinfo; i++) { 131 DEBUG("bd unit %d is BIOS device 0x%x", i, bdinfo[i].bd_unit); 132 if (bdinfo[i].bd_unit == biosdev) 133 return (i); 134 } 135 return (-1); 136 } 137 138 int 139 bd_unit2bios(int unit) 140 { 141 142 if ((unit >= 0) && (unit < nbdinfo)) 143 return (bdinfo[unit].bd_unit); 144 return (-1); 145 } 146 147 /* 148 * Quiz the BIOS for disk devices, save a little info about them. 149 */ 150 static int 151 bd_init(void) 152 { 153 int base, unit, nfd = 0; 154 155 /* sequence 0, 0x80 */ 156 for (base = 0; base <= 0x80; base += 0x80) { 157 for (unit = base; (nbdinfo < MAXBDDEV); unit++) { 158 #ifndef VIRTUALBOX 159 /* 160 * Check the BIOS equipment list for number 161 * of fixed disks. 162 */ 163 if(base == 0x80 && 164 (nfd >= *(unsigned char *)PTOV(BIOS_NUMDRIVES))) 165 break; 166 #endif 167 bdinfo[nbdinfo].bd_open = 0; 168 bdinfo[nbdinfo].bd_bcache = NULL; 169 bdinfo[nbdinfo].bd_unit = unit; 170 bdinfo[nbdinfo].bd_flags = unit < 0x80 ? BD_FLOPPY: 0; 171 if (!bd_int13probe(&bdinfo[nbdinfo])) 172 break; 173 174 #ifndef BOOT2 175 /* XXX we need "disk aliases" to make this simpler */ 176 printf("BIOS drive %c: is disk%d\n", (unit < 0x80) ? 177 ('A' + unit): ('C' + unit - 0x80), nbdinfo); 178 #endif 179 nbdinfo++; 180 if (base == 0x80) 181 nfd++; 182 } 183 } 184 bcache_add_dev(nbdinfo); 185 return(0); 186 } 187 188 /* 189 * Try to detect a device supported by the legacy int13 BIOS 190 */ 191 static int 192 bd_int13probe(struct bdinfo *bd) 193 { 194 struct edd_params params; 195 int ret = 1; /* assume success */ 196 197 v86.ctl = V86_FLAGS; 198 v86.addr = 0x13; 199 v86.eax = 0x800; 200 v86.edx = bd->bd_unit; 201 v86int(); 202 203 /* Don't error out if we get bad sector number, try EDD as well */ 204 if (V86_CY(v86.efl) || /* carry set */ 205 (v86.edx & 0xff) <= (unsigned)(bd->bd_unit & 0x7f)) /* unit # bad */ 206 return (0); /* skip device */ 207 208 if ((v86.ecx & 0x3f) == 0) /* absurd sector number */ 209 ret = 0; /* set error */ 210 211 /* Convert max cyl # -> # of cylinders */ 212 bd->bd_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1; 213 /* Convert max head # -> # of heads */ 214 bd->bd_hds = ((v86.edx & 0xff00) >> 8) + 1; 215 bd->bd_sec = v86.ecx & 0x3f; 216 bd->bd_type = v86.ebx & 0xff; 217 bd->bd_flags |= BD_MODEINT13; 218 219 /* Calculate sectors count from the geometry */ 220 bd->bd_sectors = bd->bd_cyl * bd->bd_hds * bd->bd_sec; 221 bd->bd_sectorsize = BIOSDISK_SECSIZE; 222 DEBUG("unit 0x%x geometry %d/%d/%d", bd->bd_unit, bd->bd_cyl, 223 bd->bd_hds, bd->bd_sec); 224 225 /* Determine if we can use EDD with this device. */ 226 v86.ctl = V86_FLAGS; 227 v86.addr = 0x13; 228 v86.eax = 0x4100; 229 v86.edx = bd->bd_unit; 230 v86.ebx = 0x55aa; 231 v86int(); 232 if (V86_CY(v86.efl) || /* carry set */ 233 (v86.ebx & 0xffff) != 0xaa55 || /* signature */ 234 (v86.ecx & EDD_INTERFACE_FIXED_DISK) == 0) 235 return (ret); /* return code from int13 AH=08 */ 236 237 /* EDD supported */ 238 bd->bd_flags |= BD_MODEEDD1; 239 if ((v86.eax & 0xff00) >= 0x3000) 240 bd->bd_flags |= BD_MODEEDD3; 241 /* Get disk params */ 242 params.len = sizeof(struct edd_params); 243 v86.ctl = V86_FLAGS; 244 v86.addr = 0x13; 245 v86.eax = 0x4800; 246 v86.edx = bd->bd_unit; 247 v86.ds = VTOPSEG(¶ms); 248 v86.esi = VTOPOFF(¶ms); 249 v86int(); 250 if (!V86_CY(v86.efl)) { 251 uint64_t total; 252 253 /* 254 * Sector size must be a multiple of 512 bytes. 255 * An alternate test would be to check power of 2, 256 * powerof2(params.sector_size). 257 */ 258 if (params.sector_size % BIOSDISK_SECSIZE) 259 bd->bd_sectorsize = BIOSDISK_SECSIZE; 260 else 261 bd->bd_sectorsize = params.sector_size; 262 263 total = bd->bd_sectorsize * params.sectors; 264 if (params.sectors != 0) { 265 /* Only update if we did not overflow. */ 266 if (total > params.sectors) 267 bd->bd_sectors = params.sectors; 268 } 269 270 total = (uint64_t)params.cylinders * 271 params.heads * params.sectors_per_track; 272 if (bd->bd_sectors < total) 273 bd->bd_sectors = total; 274 275 ret = 1; 276 } 277 DEBUG("unit 0x%x flags %x, sectors %llu, sectorsize %u", 278 bd->bd_unit, bd->bd_flags, bd->bd_sectors, bd->bd_sectorsize); 279 return (ret); 280 } 281 282 /* 283 * Print information about disks 284 */ 285 static int 286 bd_print(int verbose) 287 { 288 static char line[80]; 289 struct disk_devdesc dev; 290 int i, ret = 0; 291 292 if (nbdinfo == 0) 293 return (0); 294 295 printf("%s devices:", biosdisk.dv_name); 296 if ((ret = pager_output("\n")) != 0) 297 return (ret); 298 299 for (i = 0; i < nbdinfo; i++) { 300 snprintf(line, sizeof (line), 301 " disk%d: BIOS drive %c (%ju X %u):\n", i, 302 (bdinfo[i].bd_unit < 0x80) ? ('A' + bdinfo[i].bd_unit): 303 ('C' + bdinfo[i].bd_unit - 0x80), 304 (uintmax_t)bdinfo[i].bd_sectors, 305 bdinfo[i].bd_sectorsize); 306 ret = pager_output(line); 307 if (ret != 0) 308 return (ret); 309 310 dev.d_dev = &biosdisk; 311 dev.d_unit = i; 312 dev.d_slice = -1; 313 dev.d_partition = -1; 314 if (disk_open(&dev, 315 bdinfo[i].bd_sectorsize * bdinfo[i].bd_sectors, 316 bdinfo[i].bd_sectorsize) == 0) { 317 sprintf(line, " disk%d", i); 318 ret = disk_print(&dev, line, verbose); 319 disk_close(&dev); 320 if (ret != 0) 321 return (ret); 322 } 323 } 324 return (ret); 325 } 326 327 /* 328 * Attempt to open the disk described by (dev) for use by (f). 329 * 330 * Note that the philosophy here is "give them exactly what 331 * they ask for". This is necessary because being too "smart" 332 * about what the user might want leads to complications. 333 * (eg. given no slice or partition value, with a disk that is 334 * sliced - are they after the first BSD slice, or the DOS 335 * slice before it?) 336 */ 337 static int 338 bd_open(struct open_file *f, ...) 339 { 340 struct disk_devdesc *dev; 341 struct disk_devdesc disk; 342 va_list ap; 343 uint64_t size; 344 int rc; 345 346 va_start(ap, f); 347 dev = va_arg(ap, struct disk_devdesc *); 348 va_end(ap); 349 350 if (dev->d_unit < 0 || dev->d_unit >= nbdinfo) 351 return (EIO); 352 BD(dev).bd_open++; 353 if (BD(dev).bd_bcache == NULL) 354 BD(dev).bd_bcache = bcache_allocate(); 355 356 /* 357 * Read disk size from partition. 358 * This is needed to work around buggy BIOS systems returning 359 * wrong (truncated) disk media size. 360 * During bd_probe() we tested if the mulitplication of bd_sectors 361 * would overflow so it should be safe to perform here. 362 */ 363 disk.d_dev = dev->d_dev; 364 disk.d_type = dev->d_type; 365 disk.d_unit = dev->d_unit; 366 disk.d_opendata = NULL; 367 disk.d_slice = -1; 368 disk.d_partition = -1; 369 disk.d_offset = 0; 370 371 if (disk_open(&disk, BD(dev).bd_sectors * BD(dev).bd_sectorsize, 372 BD(dev).bd_sectorsize) == 0) { 373 374 if (disk_ioctl(&disk, DIOCGMEDIASIZE, &size) == 0) { 375 size /= BD(dev).bd_sectorsize; 376 if (size > BD(dev).bd_sectors) 377 BD(dev).bd_sectors = size; 378 } 379 disk_close(&disk); 380 } 381 382 rc = disk_open(dev, BD(dev).bd_sectors * BD(dev).bd_sectorsize, 383 BD(dev).bd_sectorsize); 384 if (rc != 0) { 385 BD(dev).bd_open--; 386 if (BD(dev).bd_open == 0) { 387 bcache_free(BD(dev).bd_bcache); 388 BD(dev).bd_bcache = NULL; 389 } 390 } 391 return (rc); 392 } 393 394 static int 395 bd_close(struct open_file *f) 396 { 397 struct disk_devdesc *dev; 398 399 dev = (struct disk_devdesc *)f->f_devdata; 400 BD(dev).bd_open--; 401 if (BD(dev).bd_open == 0) { 402 bcache_free(BD(dev).bd_bcache); 403 BD(dev).bd_bcache = NULL; 404 } 405 return (disk_close(dev)); 406 } 407 408 static int 409 bd_ioctl(struct open_file *f, u_long cmd, void *data) 410 { 411 struct disk_devdesc *dev; 412 int rc; 413 414 dev = (struct disk_devdesc *)f->f_devdata; 415 416 rc = disk_ioctl(dev, cmd, data); 417 if (rc != ENOTTY) 418 return (rc); 419 420 switch (cmd) { 421 case DIOCGSECTORSIZE: 422 *(u_int *)data = BD(dev).bd_sectorsize; 423 break; 424 case DIOCGMEDIASIZE: 425 *(uint64_t *)data = BD(dev).bd_sectors * BD(dev).bd_sectorsize; 426 break; 427 default: 428 return (ENOTTY); 429 } 430 return (0); 431 } 432 433 static int 434 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, 435 char *buf, size_t *rsize) 436 { 437 struct bcache_devdata bcd; 438 struct disk_devdesc *dev; 439 440 dev = (struct disk_devdesc *)devdata; 441 bcd.dv_strategy = bd_realstrategy; 442 bcd.dv_devdata = devdata; 443 bcd.dv_cache = BD(dev).bd_bcache; 444 445 return (bcache_strategy(&bcd, rw, dblk + dev->d_offset, size, 446 buf, rsize)); 447 } 448 449 static int 450 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, 451 char *buf, size_t *rsize) 452 { 453 struct disk_devdesc *dev = (struct disk_devdesc *)devdata; 454 uint64_t disk_blocks, offset; 455 size_t blks, blkoff, bsize, rest; 456 caddr_t bbuf; 457 int rc; 458 459 /* 460 * First make sure the IO size is a multiple of 512 bytes. While we do 461 * process partial reads below, the strategy mechanism is built 462 * assuming IO is a multiple of 512B blocks. If the request is not 463 * a multiple of 512B blocks, it has to be some sort of bug. 464 */ 465 if (size == 0 || (size % BIOSDISK_SECSIZE) != 0) { 466 printf("bd_strategy: %d bytes I/O not multiple of %d\n", 467 size, BIOSDISK_SECSIZE); 468 return (EIO); 469 } 470 471 DEBUG("open_disk %p", dev); 472 473 offset = dblk * BIOSDISK_SECSIZE; 474 dblk = offset / BD(dev).bd_sectorsize; 475 blkoff = offset % BD(dev).bd_sectorsize; 476 477 /* 478 * Check the value of the size argument. We do have quite small 479 * heap (64MB), but we do not know good upper limit, so we check against 480 * INT_MAX here. This will also protect us against possible overflows 481 * while translating block count to bytes. 482 */ 483 if (size > INT_MAX) { 484 DEBUG("requested read: %zu too large", size); 485 return (EIO); 486 } 487 488 blks = size / BD(dev).bd_sectorsize; 489 if (blks == 0 || (size % BD(dev).bd_sectorsize) != 0) 490 blks++; 491 492 if (dblk > dblk + blks) 493 return (EIO); 494 495 if (rsize) 496 *rsize = 0; 497 498 /* 499 * Get disk blocks, this value is either for whole disk or for 500 * partition. 501 */ 502 if (disk_ioctl(dev, DIOCGMEDIASIZE, &disk_blocks) == 0) { 503 /* DIOCGMEDIASIZE does return bytes. */ 504 disk_blocks /= BD(dev).bd_sectorsize; 505 } else { 506 /* We should not get here. Just try to survive. */ 507 disk_blocks = BD(dev).bd_sectors - dev->d_offset; 508 } 509 510 /* Validate source block address. */ 511 if (dblk < dev->d_offset || dblk >= dev->d_offset + disk_blocks) 512 return (EIO); 513 514 /* 515 * Truncate if we are crossing disk or partition end. 516 */ 517 if (dblk + blks >= dev->d_offset + disk_blocks) { 518 blks = dev->d_offset + disk_blocks - dblk; 519 size = blks * BD(dev).bd_sectorsize; 520 DEBUG("short read %d", blks); 521 } 522 523 if (V86_IO_BUFFER_SIZE / BD(dev).bd_sectorsize == 0) 524 panic("BUG: Real mode buffer is too small\n"); 525 526 bbuf = PTOV(V86_IO_BUFFER); 527 rest = size; 528 529 while (blks > 0) { 530 int x = min(blks, V86_IO_BUFFER_SIZE / BD(dev).bd_sectorsize); 531 532 switch (rw & F_MASK) { 533 case F_READ: 534 DEBUG("read %d from %lld to %p", x, dblk, buf); 535 bsize = BD(dev).bd_sectorsize * x - blkoff; 536 if (rest < bsize) 537 bsize = rest; 538 539 if ((rc = bd_io(dev, dblk, x, bbuf, 0)) != 0) 540 return (EIO); 541 542 bcopy(bbuf + blkoff, buf, bsize); 543 break; 544 case F_WRITE : 545 DEBUG("write %d from %lld to %p", x, dblk, buf); 546 if (blkoff != 0) { 547 /* 548 * We got offset to sector, read 1 sector to 549 * bbuf. 550 */ 551 x = 1; 552 bsize = BD(dev).bd_sectorsize - blkoff; 553 bsize = min(bsize, rest); 554 rc = bd_io(dev, dblk, x, bbuf, 0); 555 } else if (rest < BD(dev).bd_sectorsize) { 556 /* 557 * The remaining block is not full 558 * sector. Read 1 sector to bbuf. 559 */ 560 x = 1; 561 bsize = rest; 562 rc = bd_io(dev, dblk, x, bbuf, 0); 563 } else { 564 /* We can write full sector(s). */ 565 bsize = BD(dev).bd_sectorsize * x; 566 } 567 /* 568 * Put your Data In, Put your Data out, 569 * Put your Data In, and shake it all about 570 */ 571 bcopy(buf, bbuf + blkoff, bsize); 572 if ((rc = bd_io(dev, dblk, x, bbuf, 1)) != 0) 573 return (EIO); 574 575 break; 576 default: 577 /* DO NOTHING */ 578 return (EROFS); 579 } 580 581 blkoff = 0; 582 buf += bsize; 583 rest -= bsize; 584 blks -= x; 585 dblk += x; 586 } 587 588 if (rsize != NULL) 589 *rsize = size; 590 return (0); 591 } 592 593 static int 594 bd_edd_io(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest, 595 int dowrite) 596 { 597 static struct edd_packet packet; 598 599 packet.len = sizeof(struct edd_packet); 600 packet.count = blks; 601 packet.off = VTOPOFF(dest); 602 packet.seg = VTOPSEG(dest); 603 packet.lba = dblk; 604 v86.ctl = V86_FLAGS; 605 v86.addr = 0x13; 606 if (dowrite) 607 /* Should we Write with verify ?? 0x4302 ? */ 608 v86.eax = 0x4300; 609 else 610 v86.eax = 0x4200; 611 v86.edx = BD(dev).bd_unit; 612 v86.ds = VTOPSEG(&packet); 613 v86.esi = VTOPOFF(&packet); 614 v86int(); 615 if (V86_CY(v86.efl)) 616 return (v86.eax >> 8); 617 return (0); 618 } 619 620 static int 621 bd_chs_io(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest, 622 int dowrite) 623 { 624 u_int x, bpc, cyl, hd, sec; 625 626 bpc = BD(dev).bd_sec * BD(dev).bd_hds; /* blocks per cylinder */ 627 x = dblk; 628 cyl = x / bpc; /* block # / blocks per cylinder */ 629 x %= bpc; /* block offset into cylinder */ 630 hd = x / BD(dev).bd_sec; /* offset / blocks per track */ 631 sec = x % BD(dev).bd_sec; /* offset into track */ 632 633 /* correct sector number for 1-based BIOS numbering */ 634 sec++; 635 636 if (cyl > 1023) 637 /* CHS doesn't support cylinders > 1023. */ 638 return (1); 639 640 v86.ctl = V86_FLAGS; 641 v86.addr = 0x13; 642 if (dowrite) 643 v86.eax = 0x300 | blks; 644 else 645 v86.eax = 0x200 | blks; 646 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec; 647 v86.edx = (hd << 8) | BD(dev).bd_unit; 648 v86.es = VTOPSEG(dest); 649 v86.ebx = VTOPOFF(dest); 650 v86int(); 651 if (V86_CY(v86.efl)) 652 return (v86.eax >> 8); 653 return (0); 654 } 655 656 static int 657 bd_io(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest, 658 int dowrite) 659 { 660 u_int result, retry; 661 662 /* Just in case some idiot actually tries to read/write -1 blocks... */ 663 if (blks < 0) 664 return (-1); 665 666 /* 667 * Loop retrying the operation a couple of times. The BIOS 668 * may also retry. 669 */ 670 for (retry = 0; retry < 3; retry++) { 671 /* if retrying, reset the drive */ 672 if (retry > 0) { 673 v86.ctl = V86_FLAGS; 674 v86.addr = 0x13; 675 v86.eax = 0; 676 v86.edx = BD(dev).bd_unit; 677 v86int(); 678 } 679 680 if (BD(dev).bd_flags & BD_MODEEDD1) 681 result = bd_edd_io(dev, dblk, blks, dest, dowrite); 682 else 683 result = bd_chs_io(dev, dblk, blks, dest, dowrite); 684 685 if (result == 0) 686 break; 687 } 688 689 /* 690 * 0x20 - Controller failure. This is common error when the 691 * media is not present. 692 */ 693 if (result != 0 && result != 0x20) { 694 if (dowrite != 0) { 695 printf("%s%d: Write %d sector(s) from %p (0x%x) " 696 "to %lld: 0x%x", dev->d_dev->dv_name, dev->d_unit, 697 blks, dest, VTOP(dest), dblk, result); 698 } else { 699 printf("%s%d: Read %d sector(s) from %lld to %p " 700 "(0x%x): 0x%x", dev->d_dev->dv_name, dev->d_unit, 701 blks, dblk, dest, VTOP(dest), result); 702 } 703 704 if (result != 0) 705 return (result); 706 } 707 708 return(0); 709 } 710 711 /* 712 * Return the BIOS geometry of a given "fixed drive" in a format 713 * suitable for the legacy bootinfo structure. Since the kernel is 714 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we 715 * prefer to get the information directly, rather than rely on being 716 * able to put it together from information already maintained for 717 * different purposes and for a probably different number of drives. 718 * 719 * For valid drives, the geometry is expected in the format (31..0) 720 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are 721 * indicated by returning the geometry of a "1.2M" PC-format floppy 722 * disk. And, incidentally, what is returned is not the geometry as 723 * such but the highest valid cylinder, head, and sector numbers. 724 */ 725 u_int32_t 726 bd_getbigeom(int bunit) 727 { 728 729 v86.ctl = V86_FLAGS; 730 v86.addr = 0x13; 731 v86.eax = 0x800; 732 v86.edx = 0x80 + bunit; 733 v86int(); 734 if (V86_CY(v86.efl)) 735 return 0x4f010f; 736 return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) | 737 (v86.edx & 0xff00) | (v86.ecx & 0x3f); 738 } 739 740 /* 741 * Return a suitable dev_t value for (dev). 742 * 743 * In the case where it looks like (dev) is a SCSI disk, we allow the number of 744 * IDE disks to be specified in $num_ide_disks. There should be a Better Way. 745 */ 746 int 747 bd_getdev(struct i386_devdesc *d) 748 { 749 struct disk_devdesc *dev; 750 int biosdev; 751 int major; 752 int rootdev; 753 char *nip, *cp; 754 int i, unit; 755 756 dev = (struct disk_devdesc *)d; 757 biosdev = bd_unit2bios(dev->d_unit); 758 DEBUG("unit %d BIOS device %d", dev->d_unit, biosdev); 759 if (biosdev == -1) /* not a BIOS device */ 760 return(-1); 761 if (disk_open(dev, BD(dev).bd_sectors * BD(dev).bd_sectorsize, 762 BD(dev).bd_sectorsize) != 0) /* oops, not a viable device */ 763 return (-1); 764 else 765 disk_close(dev); 766 767 if (biosdev < 0x80) { 768 /* floppy (or emulated floppy) or ATAPI device */ 769 if (bdinfo[dev->d_unit].bd_type == DT_ATAPI) { 770 /* is an ATAPI disk */ 771 major = WFDMAJOR; 772 } else { 773 /* is a floppy disk */ 774 major = FDMAJOR; 775 } 776 } else { 777 /* assume an IDE disk */ 778 major = WDMAJOR; 779 } 780 /* default root disk unit number */ 781 unit = biosdev & 0x7f; 782 783 /* XXX a better kludge to set the root disk unit number */ 784 if ((nip = getenv("root_disk_unit")) != NULL) { 785 i = strtol(nip, &cp, 0); 786 /* check for parse error */ 787 if ((cp != nip) && (*cp == 0)) 788 unit = i; 789 } 790 791 rootdev = MAKEBOOTDEV(major, dev->d_slice + 1, unit, dev->d_partition); 792 DEBUG("dev is 0x%x\n", rootdev); 793 return(rootdev); 794 } 795