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 <stand.h> 41 42#include <sys/disklabel.h> 43#include <sys/diskpc98.h> 44#include <machine/bootinfo.h> 45 46#include <stdarg.h> 47 48#include <bootstrap.h> 49#include <btxv86.h> 50#include "libi386.h" 51 52#define BIOS_NUMDRIVES 0x475 53#define BIOSDISK_SECSIZE 512 54#define BUFSIZE (1 * BIOSDISK_SECSIZE) 55#define MAXBDDEV MAXDEV 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 69struct open_disk { 70 int od_dkunit; /* disk unit number */ 71 int od_unit; /* BIOS unit number */ 72 int od_cyl; /* BIOS geometry */ 73 int od_hds; 74 int od_sec; 75 int od_boff; /* block offset from beginning of BIOS disk */ 76 int od_flags; 77#define BD_MODEINT13 0x0000 78#define BD_MODEEDD1 0x0001 79#define BD_MODEEDD3 0x0002 80#define BD_MODEMASK 0x0003 81#define BD_FLOPPY 0x0004 82#define BD_LABELOK 0x0008 83#define BD_PARTTABOK 0x0010 84#define BD_OPTICAL 0x0020 85 struct disklabel od_disklabel; 86 int od_nslices; /* slice count */ 87 struct pc98_partition od_slicetab[NDOSPART]; 88}; 89 90/* 91 * List of BIOS devices, translation from disk unit number to 92 * BIOS unit number. 93 */ 94static struct bdinfo 95{ 96 int bd_unit; /* BIOS unit number */ 97 int bd_flags; 98 int bd_type; /* BIOS 'drive type' (floppy only) */ 99 int bd_da_unit; /* kernel unit number for da */ 100} bdinfo [MAXBDDEV]; 101static int nbdinfo = 0; 102 103static int bd_getgeom(struct open_disk *od); 104static int bd_read(struct open_disk *od, daddr_t dblk, int blks, 105 caddr_t dest); 106static int bd_write(struct open_disk *od, daddr_t dblk, int blks, 107 caddr_t dest); 108 109static int bd_int13probe(struct bdinfo *bd); 110 111static void bd_printslice(struct open_disk *od, struct pc98_partition *dp, 112 char *prefix, int verbose); 113static void bd_printbsdslice(struct open_disk *od, daddr_t offset, 114 char *prefix, int verbose); 115 116static int bd_init(void); 117static int bd_strategy(void *devdata, int flag, daddr_t dblk, 118 size_t size, char *buf, size_t *rsize); 119static int bd_realstrategy(void *devdata, int flag, daddr_t dblk, 120 size_t size, char *buf, size_t *rsize); 121static int bd_open(struct open_file *f, ...); 122static int bd_close(struct open_file *f); 123static void bd_print(int verbose); 124 125struct devsw biosdisk = { 126 "disk", 127 DEVT_DISK, 128 bd_init, 129 bd_strategy, 130 bd_open, 131 bd_close, 132 noioctl, 133 bd_print, 134 NULL 135}; 136 137static int bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev); 138static void bd_closedisk(struct open_disk *od); 139static int bd_bestslice(struct open_disk *od); 140static void bd_checkextended(struct open_disk *od, int slicenum); 141 142/* 143 * Translate between BIOS device numbers and our private unit numbers. 144 */ 145int 146bd_bios2unit(int biosdev) 147{ 148 int i; 149 150 DEBUG("looking for bios device 0x%x", biosdev); 151 for (i = 0; i < nbdinfo; i++) { 152 DEBUG("bd unit %d is BIOS device 0x%x", i, bdinfo[i].bd_unit); 153 if (bdinfo[i].bd_unit == biosdev) 154 return(i); 155 } 156 return(-1); 157} 158 159int 160bd_unit2bios(int unit) 161{ 162 if ((unit >= 0) && (unit < nbdinfo)) 163 return(bdinfo[unit].bd_unit); 164 return(-1); 165} 166 167/* 168 * Quiz the BIOS for disk devices, save a little info about them. 169 */ 170static int 171bd_init(void) 172{ 173 int base, unit; 174 int da_drive=0, n=-0x10; 175 176 /* sequence 0x90, 0x80, 0xa0 */ 177 for (base = 0x90; base <= 0xa0; base += n, n += 0x30) { 178 for (unit = base; (nbdinfo < MAXBDDEV) || ((unit & 0x0f) < 4); unit++) { 179 bdinfo[nbdinfo].bd_unit = unit; 180 bdinfo[nbdinfo].bd_flags = (unit & 0xf0) == 0x90 ? BD_FLOPPY : 0; 181 182 if (!bd_int13probe(&bdinfo[nbdinfo])){ 183 if (((unit & 0xf0) == 0x90 && (unit & 0x0f) < 4) || 184 ((unit & 0xf0) == 0xa0 && (unit & 0x0f) < 6)) 185 continue; /* Target IDs are not contiguous. */ 186 else 187 break; 188 } 189 190 if (bdinfo[nbdinfo].bd_flags & BD_FLOPPY){ 191 /* available 1.44MB access? */ 192 if (*(u_char *)PTOV(0xA15AE) & (1<<(unit & 0xf))) { 193 /* boot media 1.2MB FD? */ 194 if ((*(u_char *)PTOV(0xA1584) & 0xf0) != 0x90) 195 bdinfo[nbdinfo].bd_unit = 0x30 + (unit & 0xf); 196 } 197 } 198 else { 199 if ((unit & 0xF0) == 0xA0) /* SCSI HD or MO */ 200 bdinfo[nbdinfo].bd_da_unit = da_drive++; 201 } 202 /* XXX we need "disk aliases" to make this simpler */ 203 printf("BIOS drive %c: is disk%d\n", 204 'A' + nbdinfo, nbdinfo); 205 nbdinfo++; 206 } 207 } 208 return(0); 209} 210 211/* 212 * Try to detect a device supported by the legacy int13 BIOS 213 */ 214static int 215bd_int13probe(struct bdinfo *bd) 216{ 217 int addr; 218 219 if (bd->bd_flags & BD_FLOPPY) { 220 addr = 0xa155c; 221 } else { 222 if ((bd->bd_unit & 0xf0) == 0x80) 223 addr = 0xa155d; 224 else 225 addr = 0xa1482; 226 } 227 if ( *(u_char *)PTOV(addr) & (1<<(bd->bd_unit & 0x0f))) { 228 bd->bd_flags |= BD_MODEINT13; 229 return(1); 230 } 231 if ((bd->bd_unit & 0xF0) == 0xA0) { 232 int media = ((unsigned *)PTOV(0xA1460))[bd->bd_unit & 0x0F] & 0x1F; 233 234 if (media == 7) { /* MO */ 235 bd->bd_flags |= BD_MODEINT13 | BD_OPTICAL; 236 return(1); 237 } 238 } 239 return(0); 240} 241 242/* 243 * Print information about disks 244 */ 245static void 246bd_print(int verbose) 247{ 248 int i, j; 249 char line[80]; 250 struct i386_devdesc dev; 251 struct open_disk *od; 252 struct pc98_partition *dptr; 253 254 for (i = 0; i < nbdinfo; i++) { 255 sprintf(line, " disk%d: BIOS drive %c:\n", i, 'A' + i); 256 pager_output(line); 257 258 /* try to open the whole disk */ 259 dev.d_unit = i; 260 dev.d_kind.biosdisk.slice = -1; 261 dev.d_kind.biosdisk.partition = -1; 262 263 if (!bd_opendisk(&od, &dev)) { 264 265 /* Do we have a partition table? */ 266 if (od->od_flags & BD_PARTTABOK) { 267 dptr = &od->od_slicetab[0]; 268 269 /* Check for a "dedicated" disk */ 270 for (j = 0; j < od->od_nslices; j++) { 271 switch(dptr[j].dp_mid) { 272 case DOSMID_386BSD: 273 sprintf(line, " disk%ds%d", i, j + 1); 274 bd_printbsdslice(od, 275 dptr[j].dp_scyl * od->od_hds * od->od_sec + 276 dptr[j].dp_shd * od->od_sec + dptr[j].dp_ssect, 277 line, verbose); 278 break; 279 default: 280 break; 281 } 282 } 283 } 284 bd_closedisk(od); 285 } 286 } 287} 288 289/* 290 * Print out each valid partition in the disklabel of a FreeBSD slice. 291 * For size calculations, we assume a 512 byte sector size. 292 */ 293static void 294bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix, 295 int verbose) 296{ 297 char line[80]; 298 char buf[BIOSDISK_SECSIZE]; 299 struct disklabel *lp; 300 int i; 301 302 /* read disklabel */ 303 if (bd_read(od, offset + LABELSECTOR, 1, buf)) 304 return; 305 lp =(struct disklabel *)(&buf[0]); 306 if (lp->d_magic != DISKMAGIC) { 307 sprintf(line, "%s: FFS bad disklabel\n", prefix); 308 pager_output(line); 309 return; 310 } 311 312 /* Print partitions */ 313 for (i = 0; i < lp->d_npartitions; i++) { 314 /* 315 * For each partition, make sure we know what type of fs it is. If 316 * not, then skip it. However, since floppies often have bogus 317 * fstypes, print the 'a' partition on a floppy even if it is marked 318 * unused. 319 */ 320 if ((lp->d_partitions[i].p_fstype == FS_BSDFFS) || 321 (lp->d_partitions[i].p_fstype == FS_SWAP) || 322 (lp->d_partitions[i].p_fstype == FS_VINUM) || 323 ((lp->d_partitions[i].p_fstype == FS_UNUSED) && 324 (od->od_flags & BD_FLOPPY) && (i == 0))) { 325 326 /* Only print out statistics in verbose mode */ 327 if (verbose) 328 sprintf(line, " %s%c: %s %.6dMB (%d - %d)\n", prefix, 'a' + i, 329 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap" : 330 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" : 331 "FFS", 332 lp->d_partitions[i].p_size / 2048, 333 lp->d_partitions[i].p_offset, 334 lp->d_partitions[i].p_offset + lp->d_partitions[i].p_size); 335 else 336 sprintf(line, " %s%c: %s\n", prefix, 'a' + i, 337 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap" : 338 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" : 339 "FFS"); 340 pager_output(line); 341 } 342 } 343} 344 345 346/* 347 * Attempt to open the disk described by (dev) for use by (f). 348 * 349 * Note that the philosophy here is "give them exactly what 350 * they ask for". This is necessary because being too "smart" 351 * about what the user might want leads to complications. 352 * (eg. given no slice or partition value, with a disk that is 353 * sliced - are they after the first BSD slice, or the DOS 354 * slice before it?) 355 */ 356static int 357bd_open(struct open_file *f, ...) 358{ 359 va_list ap; 360 struct i386_devdesc *dev; 361 struct open_disk *od; 362 int error; 363 364 va_start(ap, f); 365 dev = va_arg(ap, struct i386_devdesc *); 366 va_end(ap); 367 if ((error = bd_opendisk(&od, dev))) 368 return(error); 369 370 /* 371 * Save our context 372 */ 373 ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od; 374 DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff); 375 return(0); 376} 377 378static int 379bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev) 380{ 381 struct pc98_partition *dptr; 382 struct disklabel *lp; 383 struct open_disk *od; 384 int sector, slice, i; 385 int error; 386 char buf[BUFSIZE]; 387 388 if (dev->d_unit >= nbdinfo) { 389 DEBUG("attempt to open nonexistent disk"); 390 return(ENXIO); 391 } 392 393 od = (struct open_disk *)malloc(sizeof(struct open_disk)); 394 if (!od) { 395 DEBUG("no memory"); 396 return (ENOMEM); 397 } 398 399 /* Look up BIOS unit number, intialise open_disk structure */ 400 od->od_dkunit = dev->d_unit; 401 od->od_unit = bdinfo[od->od_dkunit].bd_unit; 402 od->od_flags = bdinfo[od->od_dkunit].bd_flags; 403 od->od_boff = 0; 404 od->od_nslices = 0; 405 error = 0; 406 DEBUG("open '%s', unit 0x%x slice %d partition %c", 407 i386_fmtdev(dev), dev->d_unit, 408 dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition + 'a'); 409 410 /* Get geometry for this open (removable device may have changed) */ 411 if (bd_getgeom(od)) { 412 DEBUG("can't get geometry"); 413 error = ENXIO; 414 goto out; 415 } 416 417 /* 418 * Following calculations attempt to determine the correct value 419 * for d->od_boff by looking for the slice and partition specified, 420 * or searching for reasonable defaults. 421 */ 422 423 /* 424 * Find the slice in the DOS slice table. 425 */ 426 if (od->od_flags & BD_FLOPPY) { 427 sector = 0; 428 goto unsliced; 429 } 430 if (bd_read(od, 0, 1, buf)) { 431 DEBUG("error reading MBR"); 432 error = EIO; 433 goto out; 434 } 435 436 /* 437 * Check the slice table magic. 438 */ 439 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) { 440 /* If a slice number was explicitly supplied, this is an error */ 441 if (dev->d_kind.biosdisk.slice > 0) { 442 DEBUG("no slice table/MBR (no magic)"); 443 error = ENOENT; 444 goto out; 445 } 446 sector = 0; 447 goto unsliced; /* may be a floppy */ 448 } 449 if (bd_read(od, 1, 1, buf)) { 450 DEBUG("error reading MBR"); 451 error = EIO; 452 goto out; 453 } 454 455 /* 456 * copy the partition table, then pick up any extended partitions. 457 */ 458 bcopy(buf + DOSPARTOFF, &od->od_slicetab, 459 sizeof(struct pc98_partition) * NDOSPART); 460 od->od_nslices = NDOSPART; /* extended slices start here */ 461 od->od_flags |= BD_PARTTABOK; 462 dptr = &od->od_slicetab[0]; 463 464 /* Is this a request for the whole disk? */ 465 if (dev->d_kind.biosdisk.slice == -1) { 466 sector = 0; 467 goto unsliced; 468 } 469 470 /* 471 * if a slice number was supplied but not found, this is an error. 472 */ 473 if (dev->d_kind.biosdisk.slice > 0) { 474 slice = dev->d_kind.biosdisk.slice - 1; 475 if (slice >= od->od_nslices) { 476 DEBUG("slice %d not found", slice); 477 error = ENOENT; 478 goto out; 479 } 480 } 481 482 /* Try to auto-detect the best slice; this should always give a slice number */ 483 if (dev->d_kind.biosdisk.slice == 0) { 484 slice = bd_bestslice(od); 485 if (slice == -1) { 486 error = ENOENT; 487 goto out; 488 } 489 dev->d_kind.biosdisk.slice = slice; 490 } 491 492 dptr = &od->od_slicetab[0]; 493 /* 494 * Accept the supplied slice number unequivocally (we may be looking 495 * at a DOS partition). 496 */ 497 dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */ 498 sector = dptr->dp_scyl * od->od_hds * od->od_sec + 499 dptr->dp_shd * od->od_sec + dptr->dp_ssect; 500 { 501 int end = dptr->dp_ecyl * od->od_hds * od->od_sec + 502 dptr->dp_ehd * od->od_sec + dptr->dp_esect; 503 DEBUG("slice entry %d at %d, %d sectors", 504 dev->d_kind.biosdisk.slice - 1, sector, end-sector); 505 } 506 507 /* 508 * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition 509 */ 510 if ((dptr->dp_mid == DOSMID_386BSD) && (dev->d_kind.biosdisk.partition < 0)) 511 dev->d_kind.biosdisk.partition = 0; 512 513 unsliced: 514 /* 515 * Now we have the slice offset, look for the partition in the disklabel if we have 516 * a partition to start with. 517 * 518 * XXX we might want to check the label checksum. 519 */ 520 if (dev->d_kind.biosdisk.partition < 0) { 521 od->od_boff = sector; /* no partition, must be after the slice */ 522 DEBUG("opening raw slice"); 523 } else { 524 525 if (bd_read(od, sector + LABELSECTOR, 1, buf)) { 526 DEBUG("error reading disklabel"); 527 error = EIO; 528 goto out; 529 } 530 DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel), buf + LABELOFFSET, &od->od_disklabel); 531 bcopy(buf + LABELOFFSET, &od->od_disklabel, sizeof(struct disklabel)); 532 lp = &od->od_disklabel; 533 od->od_flags |= BD_LABELOK; 534 535 if (lp->d_magic != DISKMAGIC) { 536 DEBUG("no disklabel"); 537 error = ENOENT; 538 goto out; 539 } 540 if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) { 541 DEBUG("partition '%c' exceeds partitions in table (a-'%c')", 542 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions); 543 error = EPART; 544 goto out; 545 546 } 547 548#ifdef DISK_DEBUG 549 /* Complain if the partition is unused unless this is a floppy. */ 550 if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) && 551 !(od->od_flags & BD_FLOPPY)) 552 DEBUG("warning, partition marked as unused"); 553#endif 554 555 od->od_boff = 556 lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset - 557 lp->d_partitions[RAW_PART].p_offset + 558 sector; 559 } 560 561 out: 562 if (error) { 563 free(od); 564 } else { 565 *odp = od; /* return the open disk */ 566 } 567 return(error); 568} 569 570/* 571 * Search for a slice with the following preferences: 572 * 573 * 1: Active FreeBSD slice 574 * 2: Non-active FreeBSD slice 575 * 3: Active Linux slice 576 * 4: non-active Linux slice 577 * 5: Active FAT/FAT32 slice 578 * 6: non-active FAT/FAT32 slice 579 */ 580#define PREF_RAWDISK 0 581#define PREF_FBSD_ACT 1 582#define PREF_FBSD 2 583#define PREF_LINUX_ACT 3 584#define PREF_LINUX 4 585#define PREF_DOS_ACT 5 586#define PREF_DOS 6 587#define PREF_NONE 7 588 589/* 590 * slicelimit is in the range 0 .. NDOSPART 591 */ 592static int 593bd_bestslice(struct open_disk *od) 594{ 595 struct pc98_partition *dp; 596 int pref, preflevel; 597 int i, prefslice; 598 599 prefslice = 0; 600 preflevel = PREF_NONE; 601 602 dp = &od->od_slicetab[0]; 603 for (i = 0; i < od->od_nslices; i++, dp++) { 604 switch(dp->dp_mid & 0x7f) { 605 case DOSMID_386BSD & 0x7f: /* FreeBSD */ 606 if ((dp->dp_mid & 0x80) && 607 (preflevel > PREF_FBSD_ACT)) { 608 pref = i; 609 preflevel = PREF_FBSD_ACT; 610 } else if (preflevel > PREF_FBSD) { 611 pref = i; 612 preflevel = PREF_FBSD; 613 } 614 break; 615 616 case 0x11: /* DOS/Windows */ 617 case 0x20: 618 case 0x21: 619 case 0x22: 620 case 0x23: 621 case 0x63: 622 if ((dp->dp_mid & 0x80) && 623 (preflevel > PREF_DOS_ACT)) { 624 pref = i; 625 preflevel = PREF_DOS_ACT; 626 } else if (preflevel > PREF_DOS) { 627 pref = i; 628 preflevel = PREF_DOS; 629 } 630 break; 631 } 632 } 633 return (prefslice); 634} 635 636static int 637bd_close(struct open_file *f) 638{ 639 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data); 640 641 bd_closedisk(od); 642 return(0); 643} 644 645static void 646bd_closedisk(struct open_disk *od) 647{ 648 DEBUG("open_disk %p", od); 649#if 0 650 /* XXX is this required? (especially if disk already open...) */ 651 if (od->od_flags & BD_FLOPPY) 652 delay(3000000); 653#endif 654 free(od); 655} 656 657static int 658bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize) 659{ 660 struct bcache_devdata bcd; 661 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data); 662 663 bcd.dv_strategy = bd_realstrategy; 664 bcd.dv_devdata = devdata; 665 return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize)); 666} 667 668static int 669bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize) 670{ 671 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data); 672 int blks; 673#ifdef BD_SUPPORT_FRAGS 674 char fragbuf[BIOSDISK_SECSIZE]; 675 size_t fragsize; 676 677 fragsize = size % BIOSDISK_SECSIZE; 678#else 679 if (size % BIOSDISK_SECSIZE) 680 panic("bd_strategy: %d bytes I/O not multiple of block size", size); 681#endif 682 683 DEBUG("open_disk %p", od); 684 685 686 switch(rw){ 687 case F_READ: 688 blks = size / BIOSDISK_SECSIZE; 689 DEBUG("read %d from %d to %p", blks, dblk, buf); 690 691 if (rsize) 692 *rsize = 0; 693 if (blks && bd_read(od, dblk, blks, buf)) { 694 DEBUG("read error"); 695 return (EIO); 696 } 697#ifdef BD_SUPPORT_FRAGS 698 DEBUG("bd_strategy: frag read %d from %d+%d to %p", 699 fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE)); 700 if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) { 701 DEBUG("frag read error"); 702 return(EIO); 703 } 704 bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize); 705#endif 706 if (rsize) 707 *rsize = size; 708 return (0); 709 break; 710 711 case F_WRITE : 712 blks = size / BIOSDISK_SECSIZE; 713 DEBUG("write %d from %d to %p", blks, dblk, buf); 714 715 if (rsize) 716 *rsize = 0; 717 if (blks && bd_write(od, dblk, blks, buf)) { 718 DEBUG("write error"); 719 return (EIO); 720 } 721#ifdef BD_SUPPORT_FRAGS 722 if(fragsize) { 723 DEBUG("Attempted to write a frag"); 724 return (EIO); 725 } 726#endif 727 728 if (rsize) 729 *rsize = size; 730 return (0); 731 default: 732 /* DO NOTHING */ 733 break; 734 } 735 736 return EROFS; 737} 738 739/* Max number of sectors to bounce-buffer if the request crosses a 64k boundary */ 740#define FLOPPY_BOUNCEBUF 18 741 742static int 743bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest) 744{ 745 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer; 746 caddr_t p, xp, bbuf, breg; 747 748 /* Just in case some idiot actually tries to read -1 blocks... */ 749 if (blks < 0) 750 return (-1); 751 752 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */ 753 resid = blks; 754 p = dest; 755 756 /* Decide whether we have to bounce */ 757 if (VTOP(dest) >> 20 != 0 || 758 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16))) { 759 760 /* 761 * There is a 64k physical boundary somewhere in the destination buffer, or the 762 * destination buffer is above first 1MB of physical memory so we have 763 * to arrange a suitable bounce buffer. Allocate a buffer twice as large as we 764 * need to. Use the bottom half unless there is a break there, in which case we 765 * use the top half. 766 */ 767 x = min(od->od_sec, (unsigned)blks); 768 bbuf = alloca(x * 2 * BIOSDISK_SECSIZE); 769 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) == ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) { 770 breg = bbuf; 771 } else { 772 breg = bbuf + x * BIOSDISK_SECSIZE; 773 } 774 maxfer = x; /* limit transfers to bounce region size */ 775 } else { 776 breg = bbuf = NULL; 777 maxfer = 0; 778 } 779 780 while (resid > 0) { 781 x = dblk; 782 cyl = x / bpc; /* block # / blocks per cylinder */ 783 x %= bpc; /* block offset into cylinder */ 784 hd = x / od->od_sec; /* offset / blocks per track */ 785 sec = x % od->od_sec; /* offset into track */ 786 787 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */ 788 x = min(od->od_sec - sec, resid); 789 if (maxfer > 0) 790 x = min(x, maxfer); /* fit bounce buffer */ 791 792 /* where do we transfer to? */ 793 xp = bbuf == NULL ? p : breg; 794 795 /* correct sector number for 1-based BIOS numbering */ 796 if ((od->od_unit & 0xf0) == 0x30 || (od->od_unit & 0xf0) == 0x90) 797 sec++; 798 799 /* Loop retrying the operation a couple of times. The BIOS may also retry. */ 800 for (retry = 0; retry < 3; retry++) { 801 /* if retrying, reset the drive */ 802 if (retry > 0) { 803 v86.ctl = V86_FLAGS; 804 v86.addr = 0x1b; 805 v86.eax = 0x0300 | od->od_unit; 806 v86int(); 807 } 808 809 v86.ctl = V86_FLAGS; 810 v86.addr = 0x1b; 811 if (od->od_flags & BD_FLOPPY) { 812 v86.eax = 0xd600 | od->od_unit; 813 v86.ecx = 0x0200 | (cyl & 0xff); 814 } 815 else { 816 v86.eax = 0x0600 | od->od_unit; 817 v86.ecx = cyl; 818 } 819 if (od->od_flags & BD_OPTICAL) { 820 v86.eax &= 0xFF7F; 821 v86.ecx = dblk & 0xFFFF; 822 v86.edx = dblk >> 16; 823 } else { 824 v86.edx = (hd << 8) | sec; 825 } 826 v86.ebx = x * BIOSDISK_SECSIZE; 827 v86.es = VTOPSEG(xp); 828 v86.ebp = VTOPOFF(xp); 829 v86int(); 830 result = (v86.efl & 0x1); 831 if (result == 0) 832 break; 833 } 834 835 DEBUG("%d sectors from %d/%d/%d to %p (0x%x) %s", x, cyl, hd, od->od_flags & BD_FLOPPY ? sec - 1 : sec, p, VTOP(p), result ? "failed" : "ok"); 836 /* BUG here, cannot use v86 in printf because putchar uses it too */ 837 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x", 838 od->od_flags & BD_FLOPPY ? 0xd600 | od->od_unit : 0x0600 | od->od_unit, 839 od->od_flags & BD_FLOPPY ? 0x0200 | cyl : cyl, (hd << 8) | sec, 840 (v86.eax >> 8) & 0xff); 841 if (result) { 842 return(-1); 843 } 844 if (bbuf != NULL) 845 bcopy(breg, p, x * BIOSDISK_SECSIZE); 846 p += (x * BIOSDISK_SECSIZE); 847 dblk += x; 848 resid -= x; 849 } 850 851/* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */ 852 return(0); 853} 854 855 856static int 857bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest) 858{ 859 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer; 860 caddr_t p, xp, bbuf, breg; 861 862 /* Just in case some idiot actually tries to read -1 blocks... */ 863 if (blks < 0) 864 return (-1); 865 866 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */ 867 resid = blks; 868 p = dest; 869 870 /* Decide whether we have to bounce */ 871 if (VTOP(dest) >> 20 != 0 || 872 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16))) { 873 874 /* 875 * There is a 64k physical boundary somewhere in the destination buffer, or the 876 * destination buffer is above first 1MB of physical memory so we have 877 * to arrange a suitable bounce buffer. Allocate a buffer twice as large as we 878 * need to. Use the bottom half unless there is a break there, in which case we 879 * use the top half. 880 */ 881 x = min(od->od_sec, (unsigned)blks); 882 bbuf = alloca(x * 2 * BIOSDISK_SECSIZE); 883 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) == ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) { 884 breg = bbuf; 885 } else { 886 breg = bbuf + x * BIOSDISK_SECSIZE; 887 } 888 maxfer = x; /* limit transfers to bounce region size */ 889 } else { 890 breg = bbuf = NULL; 891 maxfer = 0; 892 } 893 894 while (resid > 0) { 895 x = dblk; 896 cyl = x / bpc; /* block # / blocks per cylinder */ 897 x %= bpc; /* block offset into cylinder */ 898 hd = x / od->od_sec; /* offset / blocks per track */ 899 sec = x % od->od_sec; /* offset into track */ 900 901 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */ 902 x = min(od->od_sec - sec, resid); 903 if (maxfer > 0) 904 x = min(x, maxfer); /* fit bounce buffer */ 905 906 /* where do we transfer to? */ 907 xp = bbuf == NULL ? p : breg; 908 909 /* correct sector number for 1-based BIOS numbering */ 910 if ((od->od_unit & 0xf0) == 0x30 || (od->od_unit & 0xf0) == 0x90) 911 sec++; 912 913 /* Put your Data In, Put your Data out, 914 Put your Data In, and shake it all about 915 */ 916 if (bbuf != NULL) 917 bcopy(p, breg, x * BIOSDISK_SECSIZE); 918 p += (x * BIOSDISK_SECSIZE); 919 dblk += x; 920 resid -= x; 921 922 /* Loop retrying the operation a couple of times. The BIOS may also retry. */ 923 for (retry = 0; retry < 3; retry++) { 924 /* if retrying, reset the drive */ 925 if (retry > 0) { 926 v86.ctl = V86_FLAGS; 927 v86.addr = 0x1b; 928 v86.eax = 0x0300 | od->od_unit; 929 v86int(); 930 } 931 932 v86.ctl = V86_FLAGS; 933 v86.addr = 0x1b; 934 if (od->od_flags & BD_FLOPPY) { 935 v86.eax = 0xd500 | od->od_unit; 936 v86.ecx = 0x0200 | (cyl & 0xff); 937 } else { 938 v86.eax = 0x0500 | od->od_unit; 939 v86.ecx = cyl; 940 } 941 v86.edx = (hd << 8) | sec; 942 v86.ebx = x * BIOSDISK_SECSIZE; 943 v86.es = VTOPSEG(xp); 944 v86.ebp = VTOPOFF(xp); 945 v86int(); 946 result = (v86.efl & 0x1); 947 if (result == 0) 948 break; 949 } 950 951 DEBUG("%d sectors from %d/%d/%d to %p (0x%x) %s", x, cyl, hd, 952 od->od_flags & BD_FLOPPY ? sec - 1 : sec, p, VTOP(p), 953 result ? "failed" : "ok"); 954 /* BUG here, cannot use v86 in printf because putchar uses it too */ 955 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x", 956 od->od_flags & BD_FLOPPY ? 0xd600 | od->od_unit : 0x0600 | od->od_unit, 957 od->od_flags & BD_FLOPPY ? 0x0200 | cyl : cyl, (hd << 8) | sec, 958 (v86.eax >> 8) & 0xff); 959 960 if (result) { 961 return(-1); 962 } 963 } 964 965/* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */ 966 return(0); 967} 968static int 969bd_getgeom(struct open_disk *od) 970{ 971 972 if (od->od_flags & BD_FLOPPY) { 973 od->od_cyl = 79; 974 od->od_hds = 2; 975 od->od_sec = (od->od_unit & 0xf0) == 0x30 ? 18 : 15; 976 } else if (od->od_flags & BD_OPTICAL) { 977 od->od_cyl = 0xFFFE; 978 od->od_hds = 8; 979 od->od_sec = 32; 980 } else { 981 v86.ctl = V86_FLAGS; 982 v86.addr = 0x1b; 983 v86.eax = 0x8400 | od->od_unit; 984 v86int(); 985 986 od->od_cyl = v86.ecx; 987 od->od_hds = (v86.edx >> 8) & 0xff; 988 od->od_sec = v86.edx & 0xff; 989 if (v86.efl & 0x1) 990 return(1); 991 } 992 993 DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec); 994 return(0); 995} 996 997/* 998 * Return the BIOS geometry of a given "fixed drive" in a format 999 * suitable for the legacy bootinfo structure. Since the kernel is 1000 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we 1001 * prefer to get the information directly, rather than rely on being 1002 * able to put it together from information already maintained for 1003 * different purposes and for a probably different number of drives. 1004 * 1005 * For valid drives, the geometry is expected in the format (31..0) 1006 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are 1007 * indicated by returning the geometry of a "1.2M" PC-format floppy 1008 * disk. And, incidentally, what is returned is not the geometry as 1009 * such but the highest valid cylinder, head, and sector numbers. 1010 */ 1011u_int32_t 1012bd_getbigeom(int bunit) 1013{ 1014 int hds = 0; 1015 int unit = 0x80; /* IDE HDD */ 1016 u_int addr = 0xA155d; 1017 1018 while (unit < 0xa7) { 1019 if (*(u_char *)PTOV(addr) & (1 << (unit & 0x0f))) 1020 if (hds++ == bunit) 1021 break; 1022 1023 if (unit >= 0xA0) { 1024 int media = ((unsigned *)PTOV(0xA1460))[unit & 0x0F] & 0x1F; 1025 1026 if (media == 7 && hds++ == bunit) /* SCSI MO */ 1027 return(0xFFFE0820); /* C:65535 H:8 S:32 */ 1028 } 1029 if (++unit == 0x84) { 1030 unit = 0xA0; /* SCSI HDD */ 1031 addr = 0xA1482; 1032 } 1033 } 1034 if (unit == 0xa7) 1035 return 0x4F020F; /* 1200KB FD C:80 H:2 S:15 */ 1036 v86.ctl = V86_FLAGS; 1037 v86.addr = 0x1b; 1038 v86.eax = 0x8400 | unit; 1039 v86int(); 1040 if (v86.efl & 0x1) 1041 return 0x4F020F; /* 1200KB FD C:80 H:2 S:15 */ 1042 return ((v86.ecx & 0xffff) << 16) | (v86.edx & 0xffff); 1043} 1044 1045/* 1046 * Return a suitable dev_t value for (dev). 1047 * 1048 * In the case where it looks like (dev) is a SCSI disk, we allow the number of 1049 * IDE disks to be specified in $num_ide_disks. There should be a Better Way. 1050 */ 1051int 1052bd_getdev(struct i386_devdesc *dev) 1053{ 1054 struct open_disk *od; 1055 int biosdev; 1056 int major; 1057 int rootdev; 1058 char *nip, *cp; 1059 int unitofs = 0, i, unit; 1060 1061 biosdev = bd_unit2bios(dev->d_unit); 1062 DEBUG("unit %d BIOS device %d", dev->d_unit, biosdev); 1063 if (biosdev == -1) /* not a BIOS device */ 1064 return(-1); 1065 if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */ 1066 return(-1); 1067 1068 if ((biosdev & 0xf0) == 0x90 || (biosdev & 0xf0) == 0x30) { 1069 /* floppy (or emulated floppy) or ATAPI device */ 1070 if (bdinfo[dev->d_unit].bd_type == DT_ATAPI) { 1071 /* is an ATAPI disk */ 1072 major = WFDMAJOR; 1073 } else { 1074 /* is a floppy disk */ 1075 major = FDMAJOR; 1076 } 1077 } else { 1078 /* harddisk */ 1079 if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) { 1080 /* label OK, disk labelled as SCSI */ 1081 major = DAMAJOR; 1082 /* check for unit number correction hint, now deprecated */ 1083 if ((nip = getenv("num_ide_disks")) != NULL) { 1084 i = strtol(nip, &cp, 0); 1085 /* check for parse error */ 1086 if ((cp != nip) && (*cp == 0)) 1087 unitofs = i; 1088 } 1089 } else { 1090 /* assume an IDE disk */ 1091 major = WDMAJOR; 1092 } 1093 } 1094 /* default root disk unit number */ 1095 if ((biosdev & 0xf0) == 0xa0) 1096 unit = bdinfo[dev->d_unit].bd_da_unit; 1097 else 1098 unit = biosdev & 0xf; 1099 1100 /* XXX a better kludge to set the root disk unit number */ 1101 if ((nip = getenv("root_disk_unit")) != NULL) { 1102 i = strtol(nip, &cp, 0); 1103 /* check for parse error */ 1104 if ((cp != nip) && (*cp == 0)) 1105 unit = i; 1106 } 1107
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