1/*- 2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD$"); 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 56#define DT_ATAPI 0x10 /* disk type for ATAPI floppies */ 57#define WDMAJOR 0 /* major numbers for devices we frontend for */ 58#define WFDMAJOR 1 59#define FDMAJOR 2 60#define DAMAJOR 4 61 62#ifdef DISK_DEBUG 63# define DEBUG(fmt, args...) printf("%s: " fmt "\n" , __func__ , ## args) 64#else 65# define DEBUG(fmt, args...) 66#endif 67 68struct open_disk { 69 int od_dkunit; /* disk unit number */ 70 int od_unit; /* BIOS unit number */ 71 int od_cyl; /* BIOS geometry */ 72 int od_hds; 73 int od_sec; 74 int od_boff; /* block offset from beginning of BIOS disk */ 75 int od_flags; 76#define BD_MODEINT13 0x0000 77#define BD_MODEEDD1 0x0001 78#define BD_MODEEDD3 0x0002 79#define BD_MODEMASK 0x0003 80#define BD_FLOPPY 0x0004 81#define BD_LABELOK 0x0008 82#define BD_PARTTABOK 0x0010 83#define BD_OPTICAL 0x0020 84 struct disklabel od_disklabel; 85 int od_nslices; /* slice count */ 86 struct pc98_partition od_slicetab[NDOSPART]; 87}; 88 89/* 90 * List of BIOS devices, translation from disk unit number to 91 * BIOS unit number. 92 */ 93static struct bdinfo 94{ 95 int bd_unit; /* BIOS unit number */ 96 int bd_flags; 97 int bd_type; /* BIOS 'drive type' (floppy only) */ 98 int bd_da_unit; /* kernel unit number for da */ 99} bdinfo [MAXBDDEV]; 100static int nbdinfo = 0; 101 102static int bd_getgeom(struct open_disk *od); 103static int bd_read(struct open_disk *od, daddr_t dblk, int blks, 104 caddr_t dest); 105static int bd_write(struct open_disk *od, daddr_t dblk, int blks, 106 caddr_t dest); 107 108static int bd_int13probe(struct bdinfo *bd); 109 110static void bd_printslice(struct open_disk *od, struct pc98_partition *dp, 111 char *prefix, int verbose); 112static void bd_printbsdslice(struct open_disk *od, daddr_t offset, 113 char *prefix, int verbose); 114 115static int bd_init(void); 116static int bd_strategy(void *devdata, int flag, daddr_t dblk, 117 size_t size, char *buf, size_t *rsize); 118static int bd_realstrategy(void *devdata, int flag, daddr_t dblk, 119 size_t size, char *buf, size_t *rsize); 120static int bd_open(struct open_file *f, ...); 121static int bd_close(struct open_file *f); 122static void bd_print(int verbose); 123 124struct devsw biosdisk = { 125 "disk", 126 DEVT_DISK, 127 bd_init, 128 bd_strategy, 129 bd_open, 130 bd_close, 131 noioctl, 132 bd_print, 133 NULL 134}; 135 136static int bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev); 137static void bd_closedisk(struct open_disk *od); 138static int bd_open_pc98(struct open_disk *od, struct i386_devdesc *dev); 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 sprintf(line, " disk%ds%d", i, j + 1); 272 bd_printslice(od, &dptr[j], line, verbose); 273 } 274 } 275 bd_closedisk(od); 276 } 277 } 278} 279 280/* Given a size in 512 byte sectors, convert it to a human-readable number. */ 281static char * 282display_size(uint64_t size) 283{ 284 static char buf[80]; 285 char unit; 286 287 size /= 2; 288 unit = 'K'; 289 if (size >= 10485760000LL) { 290 size /= 1073741824; 291 unit = 'T'; 292 } else if (size >= 10240000) { 293 size /= 1048576; 294 unit = 'G'; 295 } else if (size >= 10000) { 296 size /= 1024; 297 unit = 'M'; 298 } 299 sprintf(buf, "%6ld%cB", (long)size, unit); 300 return (buf); 301} 302 303/* 304 * Print information about slices on a disk. For the size calculations we 305 * assume a 512 byte sector. 306 */ 307static void 308bd_printslice(struct open_disk *od, struct pc98_partition *dp, char *prefix, 309 int verbose) 310{ 311 int cylsecs, start, size; 312 char stats[80]; 313 char line[80]; 314 315 cylsecs = od->od_hds * od->od_sec; 316 start = dp->dp_scyl * cylsecs + dp->dp_shd * od->od_sec + dp->dp_ssect; 317 size = (dp->dp_ecyl - dp->dp_scyl + 1) * cylsecs; 318 319 if (verbose) 320 sprintf(stats, " %s (%d - %d)", display_size(size), 321 start, start + size); 322 else 323 stats[0] = '\0'; 324 325 switch(dp->dp_mid & PC98_MID_MASK) { 326 case PC98_MID_386BSD: 327 bd_printbsdslice(od, start, prefix, verbose); 328 return; 329 case 0x00: /* unused partition */ 330 return; 331 case 0x01: 332 sprintf(line, "%s: FAT-12%s\n", prefix, stats); 333 break; 334 case 0x11: 335 case 0x20: 336 case 0x21: 337 case 0x22: 338 case 0x23: 339 case 0x24: 340 sprintf(line, "%s: FAT-16%s\n", prefix, stats); 341 break; 342 default: 343 sprintf(line, "%s: Unknown fs: 0x%x %s\n", prefix, dp->dp_mid, 344 stats); 345 } 346 pager_output(line); 347} 348 349/* 350 * Print out each valid partition in the disklabel of a FreeBSD slice. 351 * For size calculations, we assume a 512 byte sector size. 352 */ 353static void 354bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix, 355 int verbose) 356{ 357 char line[80]; 358 char buf[BIOSDISK_SECSIZE]; 359 struct disklabel *lp; 360 int i; 361 362 /* read disklabel */ 363 if (bd_read(od, offset + LABELSECTOR, 1, buf)) 364 return; 365 lp =(struct disklabel *)(&buf[0]); 366 if (lp->d_magic != DISKMAGIC) { 367 sprintf(line, "%s: FFS bad disklabel\n", prefix); 368 pager_output(line); 369 return; 370 } 371 372 /* Print partitions */ 373 for (i = 0; i < lp->d_npartitions; i++) { 374 /* 375 * For each partition, make sure we know what type of fs it is. If 376 * not, then skip it. However, since floppies often have bogus 377 * fstypes, print the 'a' partition on a floppy even if it is marked 378 * unused. 379 */ 380 if ((lp->d_partitions[i].p_fstype == FS_BSDFFS) || 381 (lp->d_partitions[i].p_fstype == FS_SWAP) || 382 (lp->d_partitions[i].p_fstype == FS_VINUM) || 383 ((lp->d_partitions[i].p_fstype == FS_UNUSED) && 384 (od->od_flags & BD_FLOPPY) && (i == 0))) { 385 386 /* Only print out statistics in verbose mode */ 387 if (verbose) 388 sprintf(line, " %s%c: %s %s (%d - %d)\n", prefix, 'a' + i, 389 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap " : 390 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" : 391 "FFS ", 392 display_size(lp->d_partitions[i].p_size), 393 lp->d_partitions[i].p_offset, 394 lp->d_partitions[i].p_offset + lp->d_partitions[i].p_size); 395 else 396 sprintf(line, " %s%c: %s\n", prefix, 'a' + i, 397 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap" : 398 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" : 399 "FFS"); 400 pager_output(line); 401 } 402 } 403} 404 405 406/* 407 * Attempt to open the disk described by (dev) for use by (f). 408 * 409 * Note that the philosophy here is "give them exactly what 410 * they ask for". This is necessary because being too "smart" 411 * about what the user might want leads to complications. 412 * (eg. given no slice or partition value, with a disk that is 413 * sliced - are they after the first BSD slice, or the DOS 414 * slice before it?) 415 */ 416static int 417bd_open(struct open_file *f, ...) 418{ 419 va_list ap; 420 struct i386_devdesc *dev; 421 struct open_disk *od; 422 int error; 423 424 va_start(ap, f); 425 dev = va_arg(ap, struct i386_devdesc *); 426 va_end(ap); 427 if ((error = bd_opendisk(&od, dev))) 428 return(error); 429 430 /* 431 * Save our context 432 */ 433 ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od; 434 DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff); 435 return(0); 436} 437 438static int 439bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev) 440{ 441 struct open_disk *od; 442 int error; 443 444 if (dev->d_unit >= nbdinfo) { 445 DEBUG("attempt to open nonexistent disk"); 446 return(ENXIO); 447 } 448 449 od = (struct open_disk *)malloc(sizeof(struct open_disk)); 450 if (!od) { 451 DEBUG("no memory"); 452 return (ENOMEM); 453 } 454 455 /* Look up BIOS unit number, intialise open_disk structure */ 456 od->od_dkunit = dev->d_unit; 457 od->od_unit = bdinfo[od->od_dkunit].bd_unit; 458 od->od_flags = bdinfo[od->od_dkunit].bd_flags; 459 od->od_boff = 0; 460 error = 0; 461 DEBUG("open '%s', unit 0x%x slice %d partition %d", 462 i386_fmtdev(dev), dev->d_unit, 463 dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition); 464 465 /* Get geometry for this open (removable device may have changed) */ 466 if (bd_getgeom(od)) { 467 DEBUG("can't get geometry"); 468 error = ENXIO; 469 goto out; 470 } 471 472 /* Determine disk layout. */ 473 error = bd_open_pc98(od, dev); 474 475 out: 476 if (error) { 477 free(od); 478 } else { 479 *odp = od; /* return the open disk */ 480 } 481 return(error); 482} 483 484static int 485bd_open_pc98(struct open_disk *od, struct i386_devdesc *dev) 486{ 487 struct pc98_partition *dptr; 488 struct disklabel *lp; 489 int sector, slice, i; 490 char buf[BUFSIZE]; 491 492 /* 493 * Following calculations attempt to determine the correct value 494 * for d->od_boff by looking for the slice and partition specified, 495 * or searching for reasonable defaults. 496 */ 497 498 /* 499 * Find the slice in the DOS slice table. 500 */ 501 od->od_nslices = 0; 502 if (od->od_flags & BD_FLOPPY) { 503 sector = 0; 504 goto unsliced; 505 } 506 if (bd_read(od, 0, 1, buf)) { 507 DEBUG("error reading MBR"); 508 return (EIO); 509 } 510 511 /* 512 * Check the slice table magic. 513 */ 514 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) { 515 /* If a slice number was explicitly supplied, this is an error */ 516 if (dev->d_kind.biosdisk.slice > 0) { 517 DEBUG("no slice table/MBR (no magic)"); 518 return (ENOENT); 519 } 520 sector = 0; 521 goto unsliced; /* may be a floppy */ 522 } 523 if (bd_read(od, 1, 1, buf)) { 524 DEBUG("error reading MBR"); 525 return (EIO); 526 } 527 528 /* 529 * copy the partition table, then pick up any extended partitions. 530 */ 531 bcopy(buf + DOSPARTOFF, &od->od_slicetab, 532 sizeof(struct pc98_partition) * NDOSPART); 533 od->od_nslices = NDOSPART; /* extended slices start here */ 534 od->od_flags |= BD_PARTTABOK; 535 dptr = &od->od_slicetab[0]; 536 537 /* Is this a request for the whole disk? */ 538 if (dev->d_kind.biosdisk.slice == -1) { 539 sector = 0; 540 goto unsliced; 541 } 542 543 /* 544 * if a slice number was supplied but not found, this is an error. 545 */ 546 if (dev->d_kind.biosdisk.slice > 0) { 547 slice = dev->d_kind.biosdisk.slice - 1; 548 if (slice >= od->od_nslices) { 549 DEBUG("slice %d not found", slice); 550 return (ENOENT); 551 } 552 } 553 554 /* Try to auto-detect the best slice; this should always give a slice number */ 555 if (dev->d_kind.biosdisk.slice == 0) { 556 slice = bd_bestslice(od); 557 if (slice == -1) { 558 return (ENOENT); 559 } 560 dev->d_kind.biosdisk.slice = slice; 561 } 562 563 dptr = &od->od_slicetab[0]; 564 /* 565 * Accept the supplied slice number unequivocally (we may be looking 566 * at a DOS partition). 567 */ 568 dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */ 569 sector = dptr->dp_scyl * od->od_hds * od->od_sec + 570 dptr->dp_shd * od->od_sec + dptr->dp_ssect; 571 { 572 int end = dptr->dp_ecyl * od->od_hds * od->od_sec + 573 dptr->dp_ehd * od->od_sec + dptr->dp_esect; 574 DEBUG("slice entry %d at %d, %d sectors", 575 dev->d_kind.biosdisk.slice - 1, sector, end-sector); 576 } 577 578 /* 579 * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition 580 */ 581 if ((dptr->dp_mid == DOSMID_386BSD) && (dev->d_kind.biosdisk.partition < 0)) 582 dev->d_kind.biosdisk.partition = 0; 583 584 unsliced: 585 /* 586 * Now we have the slice offset, look for the partition in the disklabel if we have 587 * a partition to start with. 588 * 589 * XXX we might want to check the label checksum. 590 */ 591 if (dev->d_kind.biosdisk.partition < 0) { 592 od->od_boff = sector; /* no partition, must be after the slice */ 593 DEBUG("opening raw slice"); 594 } else { 595 596 if (bd_read(od, sector + LABELSECTOR, 1, buf)) { 597 DEBUG("error reading disklabel"); 598 return (EIO); 599 } 600 DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel), buf + LABELOFFSET, &od->od_disklabel); 601 bcopy(buf + LABELOFFSET, &od->od_disklabel, sizeof(struct disklabel)); 602 lp = &od->od_disklabel; 603 od->od_flags |= BD_LABELOK; 604 605 if (lp->d_magic != DISKMAGIC) { 606 DEBUG("no disklabel"); 607 return (ENOENT); 608 } 609 if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) { 610 DEBUG("partition '%c' exceeds partitions in table (a-'%c')", 611 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions); 612 return (EPART); 613 } 614 615#ifdef DISK_DEBUG 616 /* Complain if the partition is unused unless this is a floppy. */ 617 if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) && 618 !(od->od_flags & BD_FLOPPY)) 619 DEBUG("warning, partition marked as unused"); 620#endif 621 622 od->od_boff = 623 lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset - 624 lp->d_partitions[RAW_PART].p_offset + 625 sector; 626 } 627 return (0); 628} 629 630/* 631 * Search for a slice with the following preferences: 632 * 633 * 1: Active FreeBSD slice 634 * 2: Non-active FreeBSD slice 635 * 3: Active Linux slice 636 * 4: non-active Linux slice 637 * 5: Active FAT/FAT32 slice 638 * 6: non-active FAT/FAT32 slice 639 */ 640#define PREF_RAWDISK 0 641#define PREF_FBSD_ACT 1 642#define PREF_FBSD 2 643#define PREF_LINUX_ACT 3 644#define PREF_LINUX 4 645#define PREF_DOS_ACT 5 646#define PREF_DOS 6 647#define PREF_NONE 7 648 649/* 650 * slicelimit is in the range 0 .. NDOSPART 651 */ 652static int 653bd_bestslice(struct open_disk *od) 654{ 655 struct pc98_partition *dp; 656 int pref, preflevel; 657 int i, prefslice; 658 659 prefslice = 0; 660 preflevel = PREF_NONE; 661 662 dp = &od->od_slicetab[0]; 663 for (i = 0; i < od->od_nslices; i++, dp++) { 664 switch(dp->dp_mid & PC98_MID_MASK) { 665 case PC98_MID_386BSD: /* FreeBSD */ 666 if ((dp->dp_mid & PC98_MID_BOOTABLE) && 667 (preflevel > PREF_FBSD_ACT)) { 668 pref = i; 669 preflevel = PREF_FBSD_ACT; 670 } else if (preflevel > PREF_FBSD) { 671 pref = i; 672 preflevel = PREF_FBSD; 673 } 674 break; 675 676 case 0x11: /* DOS/Windows */ 677 case 0x20: 678 case 0x21: 679 case 0x22: 680 case 0x23: 681 case 0x63: 682 if ((dp->dp_mid & PC98_MID_BOOTABLE) && 683 (preflevel > PREF_DOS_ACT)) { 684 pref = i; 685 preflevel = PREF_DOS_ACT; 686 } else if (preflevel > PREF_DOS) { 687 pref = i; 688 preflevel = PREF_DOS; 689 } 690 break; 691 } 692 } 693 return (prefslice); 694} 695 696static int 697bd_close(struct open_file *f) 698{ 699 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data); 700 701 bd_closedisk(od); 702 return(0); 703} 704 705static void 706bd_closedisk(struct open_disk *od) 707{ 708 DEBUG("open_disk %p", od); 709#if 0 710 /* XXX is this required? (especially if disk already open...) */ 711 if (od->od_flags & BD_FLOPPY) 712 delay(3000000); 713#endif 714 free(od); 715} 716 717static int 718bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize) 719{ 720 struct bcache_devdata bcd; 721 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data); 722 723 bcd.dv_strategy = bd_realstrategy; 724 bcd.dv_devdata = devdata; 725 return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize)); 726} 727 728static int 729bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize) 730{ 731 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data); 732 int blks; 733#ifdef BD_SUPPORT_FRAGS 734 char fragbuf[BIOSDISK_SECSIZE]; 735 size_t fragsize; 736 737 fragsize = size % BIOSDISK_SECSIZE; 738#else 739 if (size % BIOSDISK_SECSIZE) 740 panic("bd_strategy: %d bytes I/O not multiple of block size", size); 741#endif 742 743 DEBUG("open_disk %p", od); 744 blks = size / BIOSDISK_SECSIZE; 745 if (rsize) 746 *rsize = 0; 747 748 switch(rw){ 749 case F_READ: 750 DEBUG("read %d from %d to %p", blks, dblk, buf); 751 752 if (blks && bd_read(od, dblk, blks, buf)) { 753 DEBUG("read error"); 754 return (EIO); 755 } 756#ifdef BD_SUPPORT_FRAGS 757 DEBUG("bd_strategy: frag read %d from %d+%d to %p", 758 fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE)); 759 if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) { 760 DEBUG("frag read error"); 761 return(EIO); 762 } 763 bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize); 764#endif 765 break; 766 case F_WRITE : 767 DEBUG("write %d from %d to %p", blks, dblk, buf); 768 769 if (blks && bd_write(od, dblk, blks, buf)) { 770 DEBUG("write error"); 771 return (EIO); 772 } 773#ifdef BD_SUPPORT_FRAGS 774 if(fragsize) { 775 DEBUG("Attempted to write a frag"); 776 return (EIO); 777 } 778#endif 779 break; 780 default: 781 /* DO NOTHING */ 782 return (EROFS); 783 } 784 785 if (rsize) 786 *rsize = size; 787 return (0); 788} 789 790/* Max number of sectors to bounce-buffer if the request crosses a 64k boundary */ 791#define FLOPPY_BOUNCEBUF 18 792 793static int 794bd_chs_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write) 795{ 796 u_int x, bpc, cyl, hd, sec; 797 798 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */ 799 x = dblk; 800 cyl = x / bpc; /* block # / blocks per cylinder */ 801 x %= bpc; /* block offset into cylinder */ 802 hd = x / od->od_sec; /* offset / blocks per track */ 803 sec = x % od->od_sec; /* offset into track */ 804 805 v86.ctl = V86_FLAGS; 806 v86.addr = 0x1b; 807 if (write) 808 v86.eax = 0x0500 | od->od_unit; 809 else 810 v86.eax = 0x0600 | od->od_unit; 811 if (od->od_flags & BD_FLOPPY) { 812 v86.eax |= 0xd000; 813 v86.ecx = 0x0200 | (cyl & 0xff); 814 v86.edx = (hd << 8) | (sec + 1); 815 } else if (od->od_flags & BD_OPTICAL) { 816 v86.eax &= 0xFF7F; 817 v86.ecx = dblk & 0xFFFF; 818 v86.edx = dblk >> 16; 819 } else { 820 v86.ecx = cyl; 821 v86.edx = (hd << 8) | sec; 822 } 823 v86.ebx = blks * BIOSDISK_SECSIZE; 824 v86.es = VTOPSEG(dest); 825 v86.ebp = VTOPOFF(dest); 826 v86int(); 827 return (v86.efl & 0x1); 828} 829 830static int 831bd_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write) 832{ 833 u_int x, sec, result, resid, retry, maxfer; 834 caddr_t p, xp, bbuf, breg; 835 836 /* Just in case some idiot actually tries to read/write -1 blocks... */ 837 if (blks < 0) 838 return (-1); 839 840 resid = blks; 841 p = dest; 842 843 /* Decide whether we have to bounce */ 844 if (VTOP(dest) >> 20 != 0 || 845 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16))) { 846 847 /* 848 * There is a 64k physical boundary somewhere in the 849 * destination buffer, or the destination buffer is above 850 * first 1MB of physical memory so we have to arrange a 851 * suitable bounce buffer. Allocate a buffer twice as large 852 * as we need to. Use the bottom half unless there is a break 853 * there, in which case we use the top half. 854 */ 855 x = min(od->od_sec, (unsigned)blks); 856 bbuf = alloca(x * 2 * BIOSDISK_SECSIZE); 857 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) == 858 ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) { 859 breg = bbuf; 860 } else { 861 breg = bbuf + x * BIOSDISK_SECSIZE; 862 } 863 maxfer = x; /* limit transfers to bounce region size */ 864 } else { 865 breg = bbuf = NULL; 866 maxfer = 0; 867 } 868 869 while (resid > 0) { 870 /* 871 * Play it safe and don't cross track boundaries. 872 * (XXX this is probably unnecessary) 873 */ 874 sec = dblk % od->od_sec; /* offset into track */ 875 x = min(od->od_sec - sec, resid); 876 if (maxfer > 0) 877 x = min(x, maxfer); /* fit bounce buffer */ 878 879 /* where do we transfer to? */ 880 xp = bbuf == NULL ? p : breg; 881 882 /* 883 * Put your Data In, Put your Data out, 884 * Put your Data In, and shake it all about 885 */ 886 if (write && bbuf != NULL) 887 bcopy(p, breg, x * BIOSDISK_SECSIZE); 888 889 /* 890 * Loop retrying the operation a couple of times. The BIOS 891 * may also retry. 892 */ 893 for (retry = 0; retry < 3; retry++) { 894 /* if retrying, reset the drive */ 895 if (retry > 0) { 896 v86.ctl = V86_FLAGS; 897 v86.addr = 0x1b; 898 v86.eax = 0x0300 | od->od_unit; 899 v86int(); 900 } 901 902 result = bd_chs_io(od, dblk, x, xp, write); 903 if (result == 0) 904 break; 905 } 906 907 if (write) 908 DEBUG("Write %d sector(s) from %p (0x%x) to %lld %s", x, 909 p, VTOP(p), dblk, result ? "failed" : "ok"); 910 else 911 DEBUG("Read %d sector(s) from %lld to %p (0x%x) %s", x, 912 dblk, p, VTOP(p), result ? "failed" : "ok"); 913 if (result) { 914 return(-1); 915 } 916 if (!write && bbuf != NULL) 917 bcopy(breg, p, x * BIOSDISK_SECSIZE); 918 p += (x * BIOSDISK_SECSIZE); 919 dblk += x; 920 resid -= x; 921 } 922 923/* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */ 924 return(0); 925} 926 927static int 928bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest) 929{ 930 931 return (bd_io(od, dblk, blks, dest, 0)); 932} 933 934static int 935bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest) 936{ 937 938 return (bd_io(od, dblk, blks, dest, 1)); 939} 940 941static int 942bd_getgeom(struct open_disk *od) 943{ 944 945 if (od->od_flags & BD_FLOPPY) { 946 od->od_cyl = 79; 947 od->od_hds = 2; 948 od->od_sec = (od->od_unit & 0xf0) == 0x30 ? 18 : 15; 949 } else if (od->od_flags & BD_OPTICAL) { 950 od->od_cyl = 0xFFFE; 951 od->od_hds = 8; 952 od->od_sec = 32; 953 } else { 954 v86.ctl = V86_FLAGS; 955 v86.addr = 0x1b; 956 v86.eax = 0x8400 | od->od_unit; 957 v86int(); 958 959 od->od_cyl = v86.ecx; 960 od->od_hds = (v86.edx >> 8) & 0xff; 961 od->od_sec = v86.edx & 0xff; 962 if (v86.efl & 0x1) 963 return(1); 964 } 965 966 DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec); 967 return(0); 968} 969 970/* 971 * Return the BIOS geometry of a given "fixed drive" in a format 972 * suitable for the legacy bootinfo structure. Since the kernel is 973 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we 974 * prefer to get the information directly, rather than rely on being 975 * able to put it together from information already maintained for 976 * different purposes and for a probably different number of drives. 977 * 978 * For valid drives, the geometry is expected in the format (31..0) 979 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are 980 * indicated by returning the geometry of a "1.2M" PC-format floppy 981 * disk. And, incidentally, what is returned is not the geometry as 982 * such but the highest valid cylinder, head, and sector numbers. 983 */ 984u_int32_t 985bd_getbigeom(int bunit) 986{ 987 int hds = 0; 988 int unit = 0x80; /* IDE HDD */ 989 u_int addr = 0xA155d; 990 991 while (unit < 0xa7) { 992 if (*(u_char *)PTOV(addr) & (1 << (unit & 0x0f))) 993 if (hds++ == bunit) 994 break; 995 996 if (unit >= 0xA0) { 997 int media = ((unsigned *)PTOV(0xA1460))[unit & 0x0F] & 0x1F; 998 999 if (media == 7 && hds++ == bunit) /* SCSI MO */ 1000 return(0xFFFE0820); /* C:65535 H:8 S:32 */ 1001 } 1002 if (++unit == 0x84) { 1003 unit = 0xA0; /* SCSI HDD */ 1004 addr = 0xA1482; 1005 } 1006 } 1007 if (unit == 0xa7) 1008 return 0x4F020F; /* 1200KB FD C:80 H:2 S:15 */ 1009 v86.ctl = V86_FLAGS; 1010 v86.addr = 0x1b; 1011 v86.eax = 0x8400 | unit; 1012 v86int(); 1013 if (v86.efl & 0x1) 1014 return 0x4F020F; /* 1200KB FD C:80 H:2 S:15 */ 1015 return ((v86.ecx & 0xffff) << 16) | (v86.edx & 0xffff); 1016} 1017 1018/* 1019 * Return a suitable dev_t value for (dev). 1020 * 1021 * In the case where it looks like (dev) is a SCSI disk, we allow the number of 1022 * IDE disks to be specified in $num_ide_disks. There should be a Better Way. 1023 */ 1024int 1025bd_getdev(struct i386_devdesc *dev) 1026{ 1027 struct open_disk *od; 1028 int biosdev; 1029 int major; 1030 int rootdev; 1031 char *nip, *cp; 1032 int unitofs = 0, i, unit; 1033 1034 biosdev = bd_unit2bios(dev->d_unit); 1035 DEBUG("unit %d BIOS device %d", dev->d_unit, biosdev); 1036 if (biosdev == -1) /* not a BIOS device */ 1037 return(-1); 1038 if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */ 1039 return(-1); 1040 1041 if ((biosdev & 0xf0) == 0x90 || (biosdev & 0xf0) == 0x30) { 1042 /* floppy (or emulated floppy) or ATAPI device */ 1043 if (bdinfo[dev->d_unit].bd_type == DT_ATAPI) { 1044 /* is an ATAPI disk */ 1045 major = WFDMAJOR; 1046 } else { 1047 /* is a floppy disk */ 1048 major = FDMAJOR; 1049 } 1050 } else { 1051 /* harddisk */ 1052 if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) { 1053 /* label OK, disk labelled as SCSI */ 1054 major = DAMAJOR; 1055 /* check for unit number correction hint, now deprecated */ 1056 if ((nip = getenv("num_ide_disks")) != NULL) { 1057 i = strtol(nip, &cp, 0); 1058 /* check for parse error */ 1059 if ((cp != nip) && (*cp == 0)) 1060 unitofs = i; 1061 } 1062 } else { 1063 /* assume an IDE disk */ 1064 major = WDMAJOR; 1065 } 1066 } 1067 /* default root disk unit number */ 1068 if ((biosdev & 0xf0) == 0xa0) 1069 unit = bdinfo[dev->d_unit].bd_da_unit; 1070 else 1071 unit = biosdev & 0xf; 1072 1073 /* XXX a better kludge to set the root disk unit number */ 1074 if ((nip = getenv("root_disk_unit")) != NULL) { 1075 i = strtol(nip, &cp, 0); 1076 /* check for parse error */ 1077 if ((cp != nip) && (*cp == 0)) 1078 unit = i; 1079 } 1080 1081 rootdev = MAKEBOOTDEV(major, dev->d_kind.biosdisk.slice + 1, unit, 1082 dev->d_kind.biosdisk.partition); 1083 DEBUG("dev is 0x%x\n", rootdev); 1084 return(rootdev); 1085} 1086