2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
26 * $FreeBSD: src/sys/boot/i386/libi386/biosdisk.c,v 1.45 2004/09/21 06:46:44 wes Exp $
30 * BIOS disk device handling.
32 * Ideas and algorithms from:
34 * - NetBSD libi386/biosdisk.c
35 * - FreeBSD biosboot/disk.c
41 #include <sys/disklabel32.h>
42 #include <sys/disklabel64.h>
43 #include <sys/diskmbr.h>
44 #include <sys/dtype.h>
45 #include <machine/bootinfo.h>
49 #include <bootstrap.h>
53 #define BIOS_NUMDRIVES 0x475
54 #define BIOSDISK_SECSIZE 512
55 #define BUFSIZE (4 * BIOSDISK_SECSIZE)
56 #define MAXBDDEV MAXDEV
58 #define DT_ATAPI 0x10 /* disk type for ATAPI floppies */
59 #define WDMAJOR 0 /* major numbers for devices we frontend for */
65 # define DEBUG(fmt, args...) printf("%s: " fmt "\n" , __func__ , ## args)
67 # define DEBUG(fmt, args...)
71 int od_dkunit; /* disk unit number */
72 int od_unit; /* BIOS unit number */
73 int od_cyl; /* BIOS geometry */
76 int od_boff; /* block offset from beginning of BIOS disk */
78 #define BD_MODEINT13 0x0000
79 #define BD_MODEEDD1 0x0001
80 #define BD_MODEEDD3 0x0002
81 #define BD_MODEMASK 0x0003
82 #define BD_FLOPPY 0x0004
83 #define BD_LABELOK 0x0008
84 #define BD_PARTTABOK 0x0010
86 struct disklabel32 od_disklabel;
87 struct disklabel64 od_disklabel64;
89 int od_nslices; /* slice count */
90 struct dos_partition od_slicetab[NEXTDOSPART];
94 * List of BIOS devices, translation from disk unit number to
99 int bd_unit; /* BIOS unit number */
101 int bd_type; /* BIOS 'drive type' (floppy only) */
103 static int nbdinfo = 0;
105 static int bd_getgeom(struct open_disk *od);
106 static int bd_read(struct open_disk *od, daddr_t dblk, int blks,
108 static int bd_write(struct open_disk *od, daddr_t dblk, int blks,
111 static int bd_int13probe(struct bdinfo *bd);
113 static void bd_printslice(struct open_disk *od, struct dos_partition *dp,
114 char *prefix, int verbose);
115 static void bd_printbsdslice(struct open_disk *od, daddr_t offset,
116 char *prefix, int verbose);
118 static int bd_init(void);
119 static int bd_strategy(void *devdata, int flag, daddr_t dblk,
120 size_t size, char *buf, size_t *rsize);
121 static int bd_realstrategy(void *devdata, int flag, daddr_t dblk,
122 size_t size, char *buf, size_t *rsize);
123 static int bd_open(struct open_file *f, ...);
124 static int bd_close(struct open_file *f);
125 static void bd_print(int verbose);
127 struct devsw biosdisk = {
139 static int bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev);
140 static void bd_closedisk(struct open_disk *od);
141 static int bd_bestslice(struct open_disk *od);
142 static void bd_chainextended(struct open_disk *od, u_int32_t base, u_int32_t offset);
145 * Translate between BIOS device numbers and our private unit numbers.
148 bd_bios2unit(int biosdev)
152 DEBUG("looking for bios device 0x%x", biosdev);
153 for (i = 0; i < nbdinfo; i++) {
154 DEBUG("bd unit %d is BIOS device 0x%x", i, bdinfo[i].bd_unit);
155 if (bdinfo[i].bd_unit == biosdev)
162 bd_unit2bios(int unit)
164 if ((unit >= 0) && (unit < nbdinfo))
165 return(bdinfo[unit].bd_unit);
170 * Quiz the BIOS for disk devices, save a little info about them.
175 int base, unit, nfd = 0;
177 /* sequence 0, 0x80 */
178 for (base = 0; base <= 0x80; base += 0x80) {
179 for (unit = base; (nbdinfo < MAXBDDEV); unit++) {
180 /* check the BIOS equipment list for number of fixed disks */
182 (nfd >= *(unsigned char *)PTOV(BIOS_NUMDRIVES)))
185 bdinfo[nbdinfo].bd_unit = unit;
186 bdinfo[nbdinfo].bd_flags = (unit < 0x80) ? BD_FLOPPY : 0;
188 if (!bd_int13probe(&bdinfo[nbdinfo]))
191 /* XXX we need "disk aliases" to make this simpler */
192 printf("BIOS drive %c: is disk%d\n",
193 (unit < 0x80) ? ('A' + unit) : ('C' + unit - 0x80), nbdinfo);
203 * Try to detect a device supported by the legacy int13 BIOS
206 bd_int13probe(struct bdinfo *bd)
211 v86.edx = bd->bd_unit;
214 if (!(v86.efl & 0x1) && /* carry clear */
215 ((v86.edx & 0xff) > ((unsigned)bd->bd_unit & 0x7f))) { /* unit # OK */
218 * Ignore devices with an absurd sector size.
220 if ((v86.ecx & 0x3f) == 0) {
221 DEBUG("Invalid geometry for unit %d", bd->bd_unit);
224 bd->bd_flags |= BD_MODEINT13;
225 bd->bd_type = v86.ebx & 0xff;
227 /* Determine if we can use EDD with this device. */
229 v86.edx = bd->bd_unit;
232 if (!(v86.efl & 0x1) && /* carry clear */
233 ((v86.ebx & 0xffff) == 0xaa55) && /* signature */
234 (v86.ecx & 0x1)) { /* packets mode ok */
235 bd->bd_flags |= BD_MODEEDD1;
236 if((v86.eax & 0xff00) > 0x300)
237 bd->bd_flags |= BD_MODEEDD3;
245 * Print information about disks
248 bd_print(int verbose)
252 struct i386_devdesc dev;
253 struct open_disk *od;
254 struct dos_partition *dptr;
256 for (i = 0; i < nbdinfo; i++) {
257 sprintf(line, " disk%d: BIOS drive %c:\n", i,
258 (bdinfo[i].bd_unit < 0x80) ? ('A' + bdinfo[i].bd_unit) : ('C' + bdinfo[i].bd_unit - 0x80));
261 /* try to open the whole disk */
262 dev.d_kind.biosdisk.unit = i;
263 dev.d_kind.biosdisk.slice = -1;
264 dev.d_kind.biosdisk.partition = -1;
266 if (!bd_opendisk(&od, &dev)) {
268 /* Do we have a partition table? */
269 if (od->od_flags & BD_PARTTABOK) {
270 dptr = &od->od_slicetab[0];
272 /* Check for a "dedicated" disk */
273 if (((dptr[3].dp_typ == DOSPTYP_386BSD) ||
274 (dptr[3].dp_typ == DOSPTYP_NETBSD)) &&
275 (dptr[3].dp_start == 0) &&
276 (dptr[3].dp_size == 50000)) {
277 sprintf(line, " disk%d", i);
278 bd_printbsdslice(od, 0, line, verbose);
280 for (j = 0; j < od->od_nslices; j++) {
281 sprintf(line, " disk%ds%d", i, j + 1);
282 bd_printslice(od, &dptr[j], line, verbose);
292 * Print information about slices on a disk. For the size calculations we
293 * assume a 512 byte sector.
296 bd_printslice(struct open_disk *od, struct dos_partition *dp, char *prefix,
301 switch (dp->dp_typ) {
304 /* XXX: possibly add types 0 and 1, as in subr_disk, for gpt magic */
305 bd_printbsdslice(od, (daddr_t)dp->dp_start, prefix, verbose);
309 sprintf(line, "%s: Linux swap %.6dMB (%d - %d)\n",
310 prefix, dp->dp_size / 2048,
311 dp->dp_start, dp->dp_start + dp->dp_size);
313 sprintf(line, "%s: Linux swap\n", prefix);
318 * read the superblock to confirm this is an ext2fs partition?
321 sprintf(line, "%s: ext2fs %.6dMB (%d - %d)\n", prefix,
322 dp->dp_size / 2048, dp->dp_start,
323 dp->dp_start + dp->dp_size);
325 sprintf(line, "%s: ext2fs\n", prefix);
327 case 0x00: /* unused partition */
332 sprintf(line, "%s: FAT-12 %.6dMB (%d - %d)\n", prefix,
333 dp->dp_size / 2048, dp->dp_start,
334 dp->dp_start + dp->dp_size);
336 sprintf(line, "%s: FAT-12\n", prefix);
342 sprintf(line, "%s: FAT-16 %.6dMB (%d - %d)\n", prefix,
343 dp->dp_size / 2048, dp->dp_start,
344 dp->dp_start + dp->dp_size);
346 sprintf(line, "%s: FAT-16\n", prefix);
351 sprintf(line, "%s: FAT-32 %.6dMB (%d - %d)\n", prefix,
352 dp->dp_size / 2048, dp->dp_start,
353 dp->dp_start + dp->dp_size);
355 sprintf(line, "%s: FAT-32\n", prefix);
359 sprintf(line, "%s: Unknown fs: 0x%x %.6dMB (%d - %d)\n",
360 prefix, dp->dp_typ, dp->dp_size / 2048,
361 dp->dp_start, dp->dp_start + dp->dp_size);
363 sprintf(line, "%s: Unknown fs: 0x%x\n", prefix,
370 print_partition(u_int8_t fstype, unsigned long long offset,
371 unsigned long long size, int i, int od_flags,
372 char *prefix, int verbose, int type)
377 * For each partition, make sure we know what type of fs it is. If
378 * not, then skip it. However, since floppies often have bogus
379 * fstypes, print the 'a' partition on a floppy even if it is marked
382 if ((fstype == FS_SWAP) ||
383 (fstype == FS_VINUM) ||
384 (fstype == FS_HAMMER) ||
385 (fstype == FS_HAMMER2) ||
386 (fstype == FS_BSDFFS) ||
387 (fstype == FS_ZFS) ||
388 (fstype == FS_JFS2) ||
389 ((fstype == FS_UNUSED) &&
390 (od_flags & BD_FLOPPY) && (i == 0))) {
392 /* Only print out statistics in verbose mode */
394 sprintf(line, "%c %s%c: %s %.6lluMB (%llu - %llu)\n",
395 /* prefix disks that can be used to load modules with '*' */
396 ((fstype == FS_BSDFFS) || (fstype == FS_UNUSED) ||
397 (fstype == FS_VINUM)) ? '*' : ' ',
399 (fstype == FS_SWAP) ? "swap" :
400 (fstype == FS_VINUM) ? "vinum" :
401 (fstype == FS_HAMMER) ? "HAMMER" :
402 (fstype == FS_HAMMER2) ? "HAMMER2" :
403 (fstype == FS_JFS2) ? "JFS2" :
404 (fstype == FS_ZFS) ? "ZFS" :
405 (fstype == FS_BSDFFS) ? "FFS" :
407 (type==32)?(size / 2048):(size/1024/1024),
411 sprintf(line, "%c %s%c: %s\n",
412 /* prefix disks that can be used to load modules with '*' */
413 ((fstype == FS_BSDFFS) || (fstype == FS_UNUSED) ||
414 (fstype == FS_VINUM)) ? '*' : ' ',
416 (fstype == FS_SWAP) ? "swap" :
417 (fstype == FS_VINUM) ? "vinum" :
418 (fstype == FS_HAMMER) ? "HAMMER" :
419 (fstype == FS_HAMMER2) ? "HAMMER2" :
420 (fstype == FS_JFS2) ? "JFS2" :
421 (fstype == FS_ZFS) ? "ZFS" :
422 (fstype == FS_BSDFFS) ? "FFS" :
431 * Print out each valid partition in the disklabel of a FreeBSD slice.
432 * For size calculations, we assume a 512 byte sector size.
435 bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix,
439 char buf[BIOSDISK_SECSIZE*2];
440 struct disklabel32 *lp = NULL;
441 struct disklabel64 *lp64 = NULL;
445 if (bd_read(od, offset + LABELSECTOR32, 1, buf))
447 lp =(struct disklabel32 *)(&buf[0]);
448 if (lp->d_magic != DISKMAGIC32) {
449 if (bd_read(od, offset, 2, buf))
452 lp64 =(struct disklabel64 *)(&buf[0]);
453 if (lp64->d_magic != DISKMAGIC64) {
454 sprintf(line, "%s: bad disklabel\n", prefix);
458 lp = NULL; /* PARANOID */
461 /* We got ourselves a disklabel64 here */
462 for (i = 0; i < lp64->d_npartitions; i++) {
463 if (lp64->d_partitions[i].p_bsize == 0)
466 print_partition(lp64->d_partitions[i].p_fstype,
467 lp64->d_partitions[i].p_boffset,
468 lp64->d_partitions[i].p_bsize,
469 i, od->od_flags, prefix, verbose, 64);
472 /* Print partitions */
473 for (i = 0; i < lp->d_npartitions; i++) {
474 print_partition(lp->d_partitions[i].p_fstype,
475 lp->d_partitions[i].p_offset,
476 lp->d_partitions[i].p_size,
477 i, od->od_flags, prefix, verbose, 32);
484 * Attempt to open the disk described by (dev) for use by (f).
486 * Note that the philosophy here is "give them exactly what
487 * they ask for". This is necessary because being too "smart"
488 * about what the user might want leads to complications.
489 * (eg. given no slice or partition value, with a disk that is
490 * sliced - are they after the first BSD slice, or the DOS
494 bd_open(struct open_file *f, ...)
497 struct i386_devdesc *dev;
498 struct open_disk *od;
502 dev = va_arg(ap, struct i386_devdesc *);
504 if ((error = bd_opendisk(&od, dev)))
510 ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od;
511 DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff);
516 bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev)
518 struct dos_partition *dptr;
519 struct disklabel32 *lp;
520 struct disklabel64 *lp64;
521 struct open_disk *od;
522 int sector, slice, i;
524 static char buf[BUFSIZE];
526 if (dev->d_kind.biosdisk.unit >= nbdinfo) {
527 DEBUG("attempt to open nonexistent disk");
531 od = (struct open_disk *)malloc(sizeof(struct open_disk));
537 /* Look up BIOS unit number, intialise open_disk structure */
538 od->od_dkunit = dev->d_kind.biosdisk.unit;
539 od->od_unit = bdinfo[od->od_dkunit].bd_unit;
540 od->od_flags = bdinfo[od->od_dkunit].bd_flags;
544 DEBUG("open '%s', unit 0x%x slice %d partition %c",
545 i386_fmtdev(dev), dev->d_kind.biosdisk.unit,
546 dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition + 'a');
548 /* Get geometry for this open (removable device may have changed) */
549 if (bd_getgeom(od)) {
550 DEBUG("can't get geometry");
556 * Following calculations attempt to determine the correct value
557 * for d->od_boff by looking for the slice and partition specified,
558 * or searching for reasonable defaults.
562 * Find the slice in the DOS slice table.
564 if (bd_read(od, 0, 1, buf)) {
565 DEBUG("error reading MBR");
571 * Check the slice table magic.
573 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
574 /* If a slice number was explicitly supplied, this is an error */
575 if (dev->d_kind.biosdisk.slice > 0) {
576 DEBUG("no slice table/MBR (no magic)");
581 goto unsliced; /* may be a floppy */
585 * copy the partition table, then pick up any extended partitions. The
586 * base partition table always has four entries, even if some of them
587 * represented extended partitions. However, any additional sub-extended
588 * partitions will be silently recursed and not included in the slice
591 bcopy(buf + DOSPARTOFF, &od->od_slicetab,
592 sizeof(struct dos_partition) * NDOSPART);
593 od->od_nslices = NDOSPART;
595 dptr = &od->od_slicetab[0];
596 for (i = 0; i < NDOSPART; i++, dptr++) {
597 if ((dptr->dp_typ == DOSPTYP_EXT) || (dptr->dp_typ == DOSPTYP_EXTLBA))
598 bd_chainextended(od, dptr->dp_start, 0); /* 1st offset is zero */
600 od->od_flags |= BD_PARTTABOK;
601 dptr = &od->od_slicetab[0];
604 * Overflow entries are not loaded into memory but we still keep
605 * track of the count. Fix it up now.
607 if (od->od_nslices > NEXTDOSPART)
608 od->od_nslices = NEXTDOSPART;
611 * Is this a request for the whole disk?
613 if (dev->d_kind.biosdisk.slice == -1) {
619 * if a slice number was supplied but not found, this is an error.
621 if (dev->d_kind.biosdisk.slice > 0) {
622 slice = dev->d_kind.biosdisk.slice - 1;
623 if (slice >= od->od_nslices) {
624 DEBUG("slice %d not found", slice);
631 * Check for the historically bogus MBR found on true dedicated disks
633 if ((dptr[3].dp_typ == DOSPTYP_386BSD) &&
634 (dptr[3].dp_start == 0) &&
635 (dptr[3].dp_size == 50000)) {
640 /* Try to auto-detect the best slice; this should always give a slice number */
641 if (dev->d_kind.biosdisk.slice == 0) {
642 slice = bd_bestslice(od);
647 dev->d_kind.biosdisk.slice = slice;
650 dptr = &od->od_slicetab[0];
652 * Accept the supplied slice number unequivocally (we may be looking
653 * at a DOS partition).
655 dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */
656 sector = dptr->dp_start;
657 DEBUG("slice entry %d at %d, %d sectors", dev->d_kind.biosdisk.slice - 1, sector, dptr->dp_size);
660 * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition
662 if ((dptr->dp_typ == DOSPTYP_386BSD) && (dev->d_kind.biosdisk.partition < 0))
663 dev->d_kind.biosdisk.partition = 0;
667 * Now we have the slice offset, look for the partition in the disklabel if we have
668 * a partition to start with.
670 * XXX we might want to check the label checksum.
672 if (dev->d_kind.biosdisk.partition < 0) {
673 od->od_boff = sector; /* no partition, must be after the slice */
674 DEBUG("opening raw slice");
677 if (bd_read(od, sector + LABELSECTOR32, 1, buf)) {
678 DEBUG("error reading disklabel");
682 DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel32), buf + LABELOFFSET32, &od->od_disklabel);
683 bcopy(buf + LABELOFFSET32, &od->od_disklabel, sizeof(struct disklabel32));
684 lp = &od->od_disklabel;
686 if (lp->d_magic == DISKMAGIC32) {
687 od->od_flags |= BD_LABELOK;
689 if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) {
690 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
691 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions);
698 /* Complain if the partition is unused unless this is a floppy. */
699 if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) &&
700 !(od->od_flags & BD_FLOPPY))
701 DEBUG("warning, partition marked as unused");
705 lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset -
706 lp->d_partitions[RAW_PART].p_offset +
712 /* else maybe DISKLABEL64? */
714 if (bd_read(od, sector, (sizeof(od->od_disklabel64) + 511) / 512, buf)) {
715 DEBUG("error reading disklabel");
719 DEBUG("copy %d bytes of label from %p to %p", sizeof(od->od_disklabel64), buf, &od->od_disklabel64);
720 bcopy(buf, &od->od_disklabel64, sizeof(od->od_disklabel64));
721 lp64 = &od->od_disklabel64;
723 if (lp64->d_magic == DISKMAGIC64) {
724 od->od_flags |= BD_LABELOK;
726 if (dev->d_kind.biosdisk.partition >= lp64->d_npartitions ||
727 lp64->d_partitions[dev->d_kind.biosdisk.partition].p_bsize == 0) {
728 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
729 'a' + dev->d_kind.biosdisk.partition, 'a' + lp64->d_npartitions);
736 lp64->d_partitions[dev->d_kind.biosdisk.partition].p_boffset / 512 +
739 DEBUG("disklabel64 slice at %d", od->od_boff);
742 DEBUG("no disklabel");
751 *odp = od; /* return the open disk */
758 bd_chainextended(struct open_disk *od, u_int32_t base, u_int32_t offset)
760 char buf[BIOSDISK_SECSIZE];
761 struct dos_partition *dp1, *dp2;
764 if (bd_read(od, (daddr_t)(base + offset), 1, buf)) {
765 printf("\nerror reading extended partition table");
770 * dp1 points to the first record in the on-disk XPT,
771 * dp2 points to the next entry in the in-memory parition table.
773 * NOTE: dp2 may be out of bounds if od_nslices >= NEXTDOSPART.
775 * NOTE: unlike the extended partitions in our primary dos partition
776 * table, we do not record recursed extended partitions themselves
777 * in our in-memory partition table.
779 * NOTE: recording within our in-memory table must be breadth first
780 * ot match what the kernel does. Thus, two passes are required.
782 * NOTE: partitioning programs which support extended partitions seem
783 * to always use the first entry for the user partition and the
784 * second entry to chain, and also appear to disallow more then one
785 * extended partition at each level. Nevertheless we make our code
786 * somewhat more generic (and the same as the kernel's own slice
789 dp1 = (struct dos_partition *)(&buf[DOSPARTOFF]);
790 dp2 = &od->od_slicetab[od->od_nslices];
792 for (i = 0; i < NDOSPART; ++i, ++dp1) {
793 if (dp1->dp_scyl == 0 && dp1->dp_shd == 0 &&
794 dp1->dp_ssect == 0 && dp1->dp_start == 0 &&
798 if ((dp1->dp_typ == DOSPTYP_EXT) ||
799 (dp1->dp_typ == DOSPTYP_EXTLBA)) {
801 * breadth first traversal, must skip in the
808 * Only load up the in-memory data if we haven't overflowed
809 * our in-memory array.
811 if (od->od_nslices < NEXTDOSPART) {
812 dp2->dp_typ = dp1->dp_typ;
813 dp2->dp_start = base + offset + dp1->dp_start;
814 dp2->dp_size = dp1->dp_size;
821 * Pass 2 - handle extended partitions. Note that the extended
822 * slice itself is not stored in the slice array when we recurse,
823 * but any 'original' top-level extended slices are. This is to
824 * match what the kernel does.
827 for (i = 0; i < NDOSPART; ++i, ++dp1) {
828 if (dp1->dp_scyl == 0 && dp1->dp_shd == 0 &&
829 dp1->dp_ssect == 0 && dp1->dp_start == 0 &&
833 if ((dp1->dp_typ == DOSPTYP_EXT) ||
834 (dp1->dp_typ == DOSPTYP_EXTLBA)) {
835 bd_chainextended(od, base, dp1->dp_start);
842 * Search for a slice with the following preferences:
844 * 1: Active FreeBSD slice
845 * 2: Non-active FreeBSD slice
846 * 3: Active Linux slice
847 * 4: non-active Linux slice
848 * 5: Active FAT/FAT32 slice
849 * 6: non-active FAT/FAT32 slice
851 #define PREF_RAWDISK 0
852 #define PREF_FBSD_ACT 1
854 #define PREF_LINUX_ACT 3
856 #define PREF_DOS_ACT 5
861 * slicelimit is in the range 0 .. NDOSPART
864 bd_bestslice(struct open_disk *od)
866 struct dos_partition *dp;
871 preflevel = PREF_NONE;
873 dp = &od->od_slicetab[0];
874 for (i = 0; i < od->od_nslices; i++, dp++) {
875 switch (dp->dp_typ) {
876 case DOSPTYP_386BSD: /* FreeBSD */
877 pref = dp->dp_flag & 0x80 ? PREF_FBSD_ACT : PREF_FBSD;
881 pref = dp->dp_flag & 0x80 ? PREF_LINUX_ACT : PREF_LINUX;
884 case 0x01: /* DOS/Windows */
890 pref = dp->dp_flag & 0x80 ? PREF_DOS_ACT : PREF_DOS;
896 if (pref < preflevel) {
905 bd_close(struct open_file *f)
907 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data);
914 bd_closedisk(struct open_disk *od)
916 DEBUG("open_disk %p", od);
918 /* XXX is this required? (especially if disk already open...) */
919 if (od->od_flags & BD_FLOPPY)
926 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
928 struct bcache_devdata bcd;
929 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
931 bcd.dv_strategy = bd_realstrategy;
932 bcd.dv_devdata = devdata;
933 return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize));
937 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
939 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
941 #ifdef BD_SUPPORT_FRAGS
942 char fragbuf[BIOSDISK_SECSIZE];
945 fragsize = size % BIOSDISK_SECSIZE;
947 if (size % BIOSDISK_SECSIZE)
948 panic("bd_strategy: %d bytes I/O not multiple of block size", size);
951 DEBUG("open_disk %p", od);
955 blks = size / BIOSDISK_SECSIZE;
956 DEBUG("read %d from %d to %p", blks, dblk, buf);
960 if (blks && bd_read(od, dblk, blks, buf)) {
964 #ifdef BD_SUPPORT_FRAGS
965 DEBUG("bd_strategy: frag read %d from %d+%d to %p",
966 fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE));
967 if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) {
968 DEBUG("frag read error");
971 bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize);
977 blks = size / BIOSDISK_SECSIZE;
978 DEBUG("write %d from %d to %p", blks, dblk, buf);
982 if (blks && bd_write(od, dblk, blks, buf)) {
983 DEBUG("write error");
986 #ifdef BD_SUPPORT_FRAGS
988 DEBUG("Attempted to write a frag");
996 break; /* DO NOTHING */
1001 /* Max number of sectors to bounce-buffer if the request crosses a 64k boundary */
1002 #define FLOPPY_BOUNCEBUF 18
1005 bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1007 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer;
1008 caddr_t p, xp, bbuf, breg;
1010 /* Just in case some idiot actually tries to read -1 blocks... */
1014 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1018 /* Decide whether we have to bounce */
1019 if ((od->od_unit < 0x80) &&
1020 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16))) {
1023 * There is a 64k physical boundary somewhere in the destination buffer, so we have
1024 * to arrange a suitable bounce buffer. Allocate a buffer twice as large as we
1025 * need to. Use the bottom half unless there is a break there, in which case we
1028 x = min(FLOPPY_BOUNCEBUF, (unsigned)blks);
1029 bbuf = malloc(x * 2 * BIOSDISK_SECSIZE);
1030 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) == ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) {
1033 breg = bbuf + x * BIOSDISK_SECSIZE;
1035 maxfer = x; /* limit transfers to bounce region size */
1043 cyl = x / bpc; /* block # / blocks per cylinder */
1044 x %= bpc; /* block offset into cylinder */
1045 hd = x / od->od_sec; /* offset / blocks per track */
1046 sec = x % od->od_sec; /* offset into track */
1048 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */
1049 x = szmin(od->od_sec - sec, resid);
1051 x = min(x, maxfer); /* fit bounce buffer */
1053 /* where do we transfer to? */
1054 xp = bbuf == NULL ? p : breg;
1056 /* correct sector number for 1-based BIOS numbering */
1060 * Loop retrying the operation a couple of times. The BIOS may also
1063 for (retry = 0; retry < 3; retry++) {
1065 * If retrying, reset the drive.
1068 v86.ctl = V86_FLAGS;
1071 v86.edx = od->od_unit;
1076 * Always use EDD if the disk supports it, otherwise fall back
1077 * to CHS mode (returning an error if the cylinder number is
1080 if (od->od_flags & BD_MODEEDD1) {
1081 static unsigned short packet[8];
1085 packet[2] = VTOPOFF(xp);
1086 packet[3] = VTOPSEG(xp);
1087 packet[4] = dblk & 0xffff;
1088 packet[5] = dblk >> 16;
1091 v86.ctl = V86_FLAGS;
1094 v86.edx = od->od_unit;
1095 v86.ds = VTOPSEG(packet);
1096 v86.esi = VTOPOFF(packet);
1098 result = (v86.efl & 0x1);
1101 } else if (cyl < 1024) {
1102 /* Use normal CHS addressing */
1103 v86.ctl = V86_FLAGS;
1105 v86.eax = 0x200 | x;
1106 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1107 v86.edx = (hd << 8) | od->od_unit;
1108 v86.es = VTOPSEG(xp);
1109 v86.ebx = VTOPOFF(xp);
1111 result = (v86.efl & 0x1);
1120 DEBUG("%d sectors from %d/%d/%d to %p (0x%x) %s", x, cyl, hd, sec - 1, p, VTOP(p), result ? "failed" : "ok");
1121 /* BUG here, cannot use v86 in printf because putchar uses it too */
1122 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x",
1123 0x200 | x, ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec, (hd << 8) | od->od_unit, (v86.eax >> 8) & 0xff);
1130 bcopy(breg, p, x * BIOSDISK_SECSIZE);
1131 p += (x * BIOSDISK_SECSIZE);
1136 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1144 bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1146 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer;
1147 caddr_t p, xp, bbuf, breg;
1149 /* Just in case some idiot actually tries to read -1 blocks... */
1153 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1157 /* Decide whether we have to bounce */
1158 if ((od->od_unit < 0x80) &&
1159 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16))) {
1162 * There is a 64k physical boundary somewhere in the destination buffer, so we have
1163 * to arrange a suitable bounce buffer. Allocate a buffer twice as large as we
1164 * need to. Use the bottom half unless there is a break there, in which case we
1168 x = min(FLOPPY_BOUNCEBUF, (unsigned)blks);
1169 bbuf = malloc(x * 2 * BIOSDISK_SECSIZE);
1170 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) == ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) {
1173 breg = bbuf + x * BIOSDISK_SECSIZE;
1175 maxfer = x; /* limit transfers to bounce region size */
1183 cyl = x / bpc; /* block # / blocks per cylinder */
1184 x %= bpc; /* block offset into cylinder */
1185 hd = x / od->od_sec; /* offset / blocks per track */
1186 sec = x % od->od_sec; /* offset into track */
1188 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */
1189 x = szmin(od->od_sec - sec, resid);
1191 x = szmin(x, maxfer); /* fit bounce buffer */
1193 /* where do we transfer to? */
1194 xp = bbuf == NULL ? p : breg;
1196 /* correct sector number for 1-based BIOS numbering */
1200 /* Put your Data In, Put your Data out,
1201 Put your Data In, and shake it all about
1204 bcopy(p, breg, x * BIOSDISK_SECSIZE);
1205 p += (x * BIOSDISK_SECSIZE);
1210 * Loop retrying the operation a couple of times. The BIOS may also
1213 for (retry = 0; retry < 3; retry++) {
1215 * If retrying, reset the drive.
1218 v86.ctl = V86_FLAGS;
1221 v86.edx = od->od_unit;
1226 * Always use EDD if the disk supports it, otherwise fall back
1227 * to CHS mode (returning an error if the cylinder number is
1230 if (od->od_flags & BD_MODEEDD1) {
1231 static unsigned short packet[8];
1235 packet[2] = VTOPOFF(xp);
1236 packet[3] = VTOPSEG(xp);
1237 packet[4] = dblk & 0xffff;
1238 packet[5] = dblk >> 16;
1241 v86.ctl = V86_FLAGS;
1243 /* Should we Write with verify ?? 0x4302 ? */
1245 v86.edx = od->od_unit;
1246 v86.ds = VTOPSEG(packet);
1247 v86.esi = VTOPOFF(packet);
1249 result = (v86.efl & 0x1);
1252 } else if (cyl < 1024) {
1253 /* Use normal CHS addressing */
1254 v86.ctl = V86_FLAGS;
1256 v86.eax = 0x300 | x;
1257 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1258 v86.edx = (hd << 8) | od->od_unit;
1259 v86.es = VTOPSEG(xp);
1260 v86.ebx = VTOPOFF(xp);
1262 result = (v86.efl & 0x1);
1271 DEBUG("%d sectors from %d/%d/%d to %p (0x%x) %s", x, cyl, hd, sec - 1, p, VTOP(p), result ? "failed" : "ok");
1272 /* BUG here, cannot use v86 in printf because putchar uses it too */
1273 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x",
1274 0x200 | x, ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec, (hd << 8) | od->od_unit, (v86.eax >> 8) & 0xff);
1282 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1288 bd_getgeom(struct open_disk *od)
1291 v86.ctl = V86_FLAGS;
1294 v86.edx = od->od_unit;
1297 if ((v86.efl & 0x1) || /* carry set */
1298 ((v86.edx & 0xff) <= (unsigned)(od->od_unit & 0x7f))) /* unit # bad */
1301 /* convert max cyl # -> # of cylinders */
1302 od->od_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1;
1303 /* convert max head # -> # of heads */
1304 od->od_hds = ((v86.edx & 0xff00) >> 8) + 1;
1305 od->od_sec = v86.ecx & 0x3f;
1307 DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec);
1312 * Return the BIOS geometry of a given "fixed drive" in a format
1313 * suitable for the legacy bootinfo structure. Since the kernel is
1314 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we
1315 * prefer to get the information directly, rather than rely on being
1316 * able to put it together from information already maintained for
1317 * different purposes and for a probably different number of drives.
1319 * For valid drives, the geometry is expected in the format (31..0)
1320 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are
1321 * indicated by returning the geometry of a "1.2M" PC-format floppy
1322 * disk. And, incidentally, what is returned is not the geometry as
1323 * such but the highest valid cylinder, head, and sector numbers.
1326 bd_getbigeom(int bunit)
1329 v86.ctl = V86_FLAGS;
1332 v86.edx = 0x80 + bunit;
1336 return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
1337 (v86.edx & 0xff00) | (v86.ecx & 0x3f);
1341 * Return a suitable cdev_t value for (dev).
1343 * In the case where it looks like (dev) is a SCSI disk, we allow the number of
1344 * IDE disks to be specified in $num_ide_disks. There should be a Better Way.
1347 bd_getdev(struct i386_devdesc *dev)
1349 struct open_disk *od;
1354 int unitofs = 0, i, unit;
1356 biosdev = bd_unit2bios(dev->d_kind.biosdisk.unit);
1357 DEBUG("unit %d BIOS device %d", dev->d_kind.biosdisk.unit, biosdev);
1358 if (biosdev == -1) /* not a BIOS device */
1360 if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */
1363 if (biosdev < 0x80) {
1364 /* floppy (or emulated floppy) or ATAPI device */
1365 if (bdinfo[dev->d_kind.biosdisk.unit].bd_type == DT_ATAPI) {
1366 /* is an ATAPI disk */
1369 /* is a floppy disk */
1374 if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) {
1375 /* label OK, disk labelled as SCSI */
1377 /* check for unit number correction hint, now deprecated */
1378 if ((nip = getenv("num_ide_disks")) != NULL) {
1379 i = strtol(nip, &cp, 0);
1380 /* check for parse error */
1381 if ((cp != nip) && (*cp == 0))
1385 /* assume an IDE disk */
1389 /* default root disk unit number */
1390 unit = (biosdev & 0x7f) - unitofs;
1392 /* XXX a better kludge to set the root disk unit number */
1393 if ((nip = getenv("root_disk_unit")) != NULL) {
1394 i = strtol(nip, &cp, 0);
1395 /* check for parse error */
1396 if ((cp != nip) && (*cp == 0))
1400 rootdev = MAKEBOOTDEV(major,
1401 (dev->d_kind.biosdisk.slice + 1) >> 4, /* XXX slices may be wrong here */
1402 (dev->d_kind.biosdisk.slice + 1) & 0xf,
1404 dev->d_kind.biosdisk.partition);
1405 DEBUG("dev is 0x%x\n", rootdev);