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_BSDFFS) ||
386 (fstype == FS_ZFS) ||
387 (fstype == FS_JFS2) ||
388 ((fstype == FS_UNUSED) &&
389 (od_flags & BD_FLOPPY) && (i == 0))) {
391 /* Only print out statistics in verbose mode */
393 sprintf(line, "%c %s%c: %s %.6lluMB (%llu - %llu)\n",
394 /* prefix disks that can be used to load modules with '*' */
395 ((fstype == FS_BSDFFS) || (fstype == FS_UNUSED) ||
396 (fstype == FS_VINUM)) ? '*' : ' ',
398 (fstype == FS_SWAP) ? "swap" :
399 (fstype == FS_VINUM) ? "vinum" :
400 (fstype == FS_HAMMER) ? "HAMMER" :
401 (fstype == FS_JFS2) ? "JFS2" :
402 (fstype == FS_ZFS) ? "ZFS" :
403 (fstype == FS_BSDFFS) ? "FFS" :
405 (type==32)?(size / 2048):(size/1024/1024),
409 sprintf(line, "%c %s%c: %s\n",
410 /* prefix disks that can be used to load modules with '*' */
411 ((fstype == FS_BSDFFS) || (fstype == FS_UNUSED) ||
412 (fstype == FS_VINUM)) ? '*' : ' ',
414 (fstype == FS_SWAP) ? "swap" :
415 (fstype == FS_VINUM) ? "vinum" :
416 (fstype == FS_HAMMER) ? "HAMMER" :
417 (fstype == FS_JFS2) ? "JFS2" :
418 (fstype == FS_ZFS) ? "ZFS" :
419 (fstype == FS_BSDFFS) ? "FFS" :
428 * Print out each valid partition in the disklabel of a FreeBSD slice.
429 * For size calculations, we assume a 512 byte sector size.
432 bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix,
436 char buf[BIOSDISK_SECSIZE*2];
437 struct disklabel32 *lp = NULL;
438 struct disklabel64 *lp64 = NULL;
442 if (bd_read(od, offset + LABELSECTOR32, 1, buf))
444 lp =(struct disklabel32 *)(&buf[0]);
445 if (lp->d_magic != DISKMAGIC32) {
446 if (bd_read(od, offset, 2, buf))
449 lp64 =(struct disklabel64 *)(&buf[0]);
450 if (lp64->d_magic != DISKMAGIC64) {
451 sprintf(line, "%s: bad disklabel\n", prefix);
455 lp = NULL; /* PARANOID */
458 /* We got ourselves a disklabel64 here */
459 for (i = 0; i < lp64->d_npartitions; i++) {
460 if (lp64->d_partitions[i].p_bsize == 0)
463 print_partition(lp64->d_partitions[i].p_fstype,
464 lp64->d_partitions[i].p_boffset,
465 lp64->d_partitions[i].p_bsize,
466 i, od->od_flags, prefix, verbose, 64);
469 /* Print partitions */
470 for (i = 0; i < lp->d_npartitions; i++) {
471 print_partition(lp->d_partitions[i].p_fstype,
472 lp->d_partitions[i].p_offset,
473 lp->d_partitions[i].p_size,
474 i, od->od_flags, prefix, verbose, 32);
481 * Attempt to open the disk described by (dev) for use by (f).
483 * Note that the philosophy here is "give them exactly what
484 * they ask for". This is necessary because being too "smart"
485 * about what the user might want leads to complications.
486 * (eg. given no slice or partition value, with a disk that is
487 * sliced - are they after the first BSD slice, or the DOS
491 bd_open(struct open_file *f, ...)
494 struct i386_devdesc *dev;
495 struct open_disk *od;
499 dev = va_arg(ap, struct i386_devdesc *);
501 if ((error = bd_opendisk(&od, dev)))
507 ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od;
508 DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff);
513 bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev)
515 struct dos_partition *dptr;
516 struct disklabel32 *lp;
517 struct disklabel64 *lp64;
518 struct open_disk *od;
519 int sector, slice, i;
521 static char buf[BUFSIZE];
523 if (dev->d_kind.biosdisk.unit >= nbdinfo) {
524 DEBUG("attempt to open nonexistent disk");
528 od = (struct open_disk *)malloc(sizeof(struct open_disk));
534 /* Look up BIOS unit number, intialise open_disk structure */
535 od->od_dkunit = dev->d_kind.biosdisk.unit;
536 od->od_unit = bdinfo[od->od_dkunit].bd_unit;
537 od->od_flags = bdinfo[od->od_dkunit].bd_flags;
541 DEBUG("open '%s', unit 0x%x slice %d partition %c",
542 i386_fmtdev(dev), dev->d_kind.biosdisk.unit,
543 dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition + 'a');
545 /* Get geometry for this open (removable device may have changed) */
546 if (bd_getgeom(od)) {
547 DEBUG("can't get geometry");
553 * Following calculations attempt to determine the correct value
554 * for d->od_boff by looking for the slice and partition specified,
555 * or searching for reasonable defaults.
559 * Find the slice in the DOS slice table.
561 if (bd_read(od, 0, 1, buf)) {
562 DEBUG("error reading MBR");
568 * Check the slice table magic.
570 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
571 /* If a slice number was explicitly supplied, this is an error */
572 if (dev->d_kind.biosdisk.slice > 0) {
573 DEBUG("no slice table/MBR (no magic)");
578 goto unsliced; /* may be a floppy */
582 * copy the partition table, then pick up any extended partitions. The
583 * base partition table always has four entries, even if some of them
584 * represented extended partitions. However, any additional sub-extended
585 * partitions will be silently recursed and not included in the slice
588 bcopy(buf + DOSPARTOFF, &od->od_slicetab,
589 sizeof(struct dos_partition) * NDOSPART);
590 od->od_nslices = NDOSPART;
592 dptr = &od->od_slicetab[0];
593 for (i = 0; i < NDOSPART; i++, dptr++) {
594 if ((dptr->dp_typ == DOSPTYP_EXT) || (dptr->dp_typ == DOSPTYP_EXTLBA))
595 bd_chainextended(od, dptr->dp_start, 0); /* 1st offset is zero */
597 od->od_flags |= BD_PARTTABOK;
598 dptr = &od->od_slicetab[0];
601 * Overflow entries are not loaded into memory but we still keep
602 * track of the count. Fix it up now.
604 if (od->od_nslices > NEXTDOSPART)
605 od->od_nslices = NEXTDOSPART;
608 * Is this a request for the whole disk?
610 if (dev->d_kind.biosdisk.slice == -1) {
616 * if a slice number was supplied but not found, this is an error.
618 if (dev->d_kind.biosdisk.slice > 0) {
619 slice = dev->d_kind.biosdisk.slice - 1;
620 if (slice >= od->od_nslices) {
621 DEBUG("slice %d not found", slice);
628 * Check for the historically bogus MBR found on true dedicated disks
630 if ((dptr[3].dp_typ == DOSPTYP_386BSD) &&
631 (dptr[3].dp_start == 0) &&
632 (dptr[3].dp_size == 50000)) {
637 /* Try to auto-detect the best slice; this should always give a slice number */
638 if (dev->d_kind.biosdisk.slice == 0) {
639 slice = bd_bestslice(od);
644 dev->d_kind.biosdisk.slice = slice;
647 dptr = &od->od_slicetab[0];
649 * Accept the supplied slice number unequivocally (we may be looking
650 * at a DOS partition).
652 dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */
653 sector = dptr->dp_start;
654 DEBUG("slice entry %d at %d, %d sectors", dev->d_kind.biosdisk.slice - 1, sector, dptr->dp_size);
657 * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition
659 if ((dptr->dp_typ == DOSPTYP_386BSD) && (dev->d_kind.biosdisk.partition < 0))
660 dev->d_kind.biosdisk.partition = 0;
664 * Now we have the slice offset, look for the partition in the disklabel if we have
665 * a partition to start with.
667 * XXX we might want to check the label checksum.
669 if (dev->d_kind.biosdisk.partition < 0) {
670 od->od_boff = sector; /* no partition, must be after the slice */
671 DEBUG("opening raw slice");
674 if (bd_read(od, sector + LABELSECTOR32, 1, buf)) {
675 DEBUG("error reading disklabel");
679 DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel32), buf + LABELOFFSET32, &od->od_disklabel);
680 bcopy(buf + LABELOFFSET32, &od->od_disklabel, sizeof(struct disklabel32));
681 lp = &od->od_disklabel;
683 if (lp->d_magic == DISKMAGIC32) {
684 od->od_flags |= BD_LABELOK;
686 if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) {
687 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
688 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions);
695 /* Complain if the partition is unused unless this is a floppy. */
696 if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) &&
697 !(od->od_flags & BD_FLOPPY))
698 DEBUG("warning, partition marked as unused");
702 lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset -
703 lp->d_partitions[RAW_PART].p_offset +
709 /* else maybe DISKLABEL64? */
711 if (bd_read(od, sector, (sizeof(od->od_disklabel64) + 511) / 512, buf)) {
712 DEBUG("error reading disklabel");
716 DEBUG("copy %d bytes of label from %p to %p", sizeof(od->od_disklabel64), buf, &od->od_disklabel64);
717 bcopy(buf, &od->od_disklabel64, sizeof(od->od_disklabel64));
718 lp64 = &od->od_disklabel64;
720 if (lp64->d_magic == DISKMAGIC64) {
721 od->od_flags |= BD_LABELOK;
723 if (dev->d_kind.biosdisk.partition >= lp64->d_npartitions ||
724 lp64->d_partitions[dev->d_kind.biosdisk.partition].p_bsize == 0) {
725 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
726 'a' + dev->d_kind.biosdisk.partition, 'a' + lp64->d_npartitions);
733 lp64->d_partitions[dev->d_kind.biosdisk.partition].p_boffset / 512 +
736 DEBUG("disklabel64 slice at %d", od->od_boff);
739 DEBUG("no disklabel");
748 *odp = od; /* return the open disk */
755 bd_chainextended(struct open_disk *od, u_int32_t base, u_int32_t offset)
757 char buf[BIOSDISK_SECSIZE];
758 struct dos_partition *dp1, *dp2;
761 if (bd_read(od, (daddr_t)(base + offset), 1, buf)) {
762 printf("\nerror reading extended partition table");
767 * dp1 points to the first record in the on-disk XPT,
768 * dp2 points to the next entry in the in-memory parition table.
770 * NOTE: dp2 may be out of bounds if od_nslices >= NEXTDOSPART.
772 * NOTE: unlike the extended partitions in our primary dos partition
773 * table, we do not record recursed extended partitions themselves
774 * in our in-memory partition table.
776 * NOTE: recording within our in-memory table must be breadth first
777 * ot match what the kernel does. Thus, two passes are required.
779 * NOTE: partitioning programs which support extended partitions seem
780 * to always use the first entry for the user partition and the
781 * second entry to chain, and also appear to disallow more then one
782 * extended partition at each level. Nevertheless we make our code
783 * somewhat more generic (and the same as the kernel's own slice
786 dp1 = (struct dos_partition *)(&buf[DOSPARTOFF]);
787 dp2 = &od->od_slicetab[od->od_nslices];
789 for (i = 0; i < NDOSPART; ++i, ++dp1) {
790 if (dp1->dp_scyl == 0 && dp1->dp_shd == 0 &&
791 dp1->dp_ssect == 0 && dp1->dp_start == 0 &&
795 if ((dp1->dp_typ == DOSPTYP_EXT) ||
796 (dp1->dp_typ == DOSPTYP_EXTLBA)) {
798 * breadth first traversal, must skip in the
805 * Only load up the in-memory data if we haven't overflowed
806 * our in-memory array.
808 if (od->od_nslices < NEXTDOSPART) {
809 dp2->dp_typ = dp1->dp_typ;
810 dp2->dp_start = base + offset + dp1->dp_start;
811 dp2->dp_size = dp1->dp_size;
818 * Pass 2 - handle extended partitions. Note that the extended
819 * slice itself is not stored in the slice array when we recurse,
820 * but any 'original' top-level extended slices are. This is to
821 * match what the kernel does.
824 for (i = 0; i < NDOSPART; ++i, ++dp1) {
825 if (dp1->dp_scyl == 0 && dp1->dp_shd == 0 &&
826 dp1->dp_ssect == 0 && dp1->dp_start == 0 &&
830 if ((dp1->dp_typ == DOSPTYP_EXT) ||
831 (dp1->dp_typ == DOSPTYP_EXTLBA)) {
832 bd_chainextended(od, base, dp1->dp_start);
839 * Search for a slice with the following preferences:
841 * 1: Active FreeBSD slice
842 * 2: Non-active FreeBSD slice
843 * 3: Active Linux slice
844 * 4: non-active Linux slice
845 * 5: Active FAT/FAT32 slice
846 * 6: non-active FAT/FAT32 slice
848 #define PREF_RAWDISK 0
849 #define PREF_FBSD_ACT 1
851 #define PREF_LINUX_ACT 3
853 #define PREF_DOS_ACT 5
858 * slicelimit is in the range 0 .. NDOSPART
861 bd_bestslice(struct open_disk *od)
863 struct dos_partition *dp;
868 preflevel = PREF_NONE;
870 dp = &od->od_slicetab[0];
871 for (i = 0; i < od->od_nslices; i++, dp++) {
872 switch (dp->dp_typ) {
873 case DOSPTYP_386BSD: /* FreeBSD */
874 pref = dp->dp_flag & 0x80 ? PREF_FBSD_ACT : PREF_FBSD;
878 pref = dp->dp_flag & 0x80 ? PREF_LINUX_ACT : PREF_LINUX;
881 case 0x01: /* DOS/Windows */
887 pref = dp->dp_flag & 0x80 ? PREF_DOS_ACT : PREF_DOS;
893 if (pref < preflevel) {
902 bd_close(struct open_file *f)
904 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data);
911 bd_closedisk(struct open_disk *od)
913 DEBUG("open_disk %p", od);
915 /* XXX is this required? (especially if disk already open...) */
916 if (od->od_flags & BD_FLOPPY)
923 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
925 struct bcache_devdata bcd;
926 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
928 bcd.dv_strategy = bd_realstrategy;
929 bcd.dv_devdata = devdata;
930 return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize));
934 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
936 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
938 #ifdef BD_SUPPORT_FRAGS
939 char fragbuf[BIOSDISK_SECSIZE];
942 fragsize = size % BIOSDISK_SECSIZE;
944 if (size % BIOSDISK_SECSIZE)
945 panic("bd_strategy: %d bytes I/O not multiple of block size", size);
948 DEBUG("open_disk %p", od);
952 blks = size / BIOSDISK_SECSIZE;
953 DEBUG("read %d from %d to %p", blks, dblk, buf);
957 if (blks && bd_read(od, dblk, blks, buf)) {
961 #ifdef BD_SUPPORT_FRAGS
962 DEBUG("bd_strategy: frag read %d from %d+%d to %p",
963 fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE));
964 if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) {
965 DEBUG("frag read error");
968 bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize);
974 blks = size / BIOSDISK_SECSIZE;
975 DEBUG("write %d from %d to %p", blks, dblk, buf);
979 if (blks && bd_write(od, dblk, blks, buf)) {
980 DEBUG("write error");
983 #ifdef BD_SUPPORT_FRAGS
985 DEBUG("Attempted to write a frag");
993 break; /* DO NOTHING */
998 /* Max number of sectors to bounce-buffer if the request crosses a 64k boundary */
999 #define FLOPPY_BOUNCEBUF 18
1002 bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1004 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer;
1005 caddr_t p, xp, bbuf, breg;
1007 /* Just in case some idiot actually tries to read -1 blocks... */
1011 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1015 /* Decide whether we have to bounce */
1016 if ((od->od_unit < 0x80) &&
1017 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16))) {
1020 * There is a 64k physical boundary somewhere in the destination buffer, so we have
1021 * to arrange a suitable bounce buffer. Allocate a buffer twice as large as we
1022 * need to. Use the bottom half unless there is a break there, in which case we
1025 x = min(FLOPPY_BOUNCEBUF, (unsigned)blks);
1026 bbuf = malloc(x * 2 * BIOSDISK_SECSIZE);
1027 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) == ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) {
1030 breg = bbuf + x * BIOSDISK_SECSIZE;
1032 maxfer = x; /* limit transfers to bounce region size */
1040 cyl = x / bpc; /* block # / blocks per cylinder */
1041 x %= bpc; /* block offset into cylinder */
1042 hd = x / od->od_sec; /* offset / blocks per track */
1043 sec = x % od->od_sec; /* offset into track */
1045 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */
1046 x = szmin(od->od_sec - sec, resid);
1048 x = min(x, maxfer); /* fit bounce buffer */
1050 /* where do we transfer to? */
1051 xp = bbuf == NULL ? p : breg;
1053 /* correct sector number for 1-based BIOS numbering */
1057 * Loop retrying the operation a couple of times. The BIOS may also
1060 for (retry = 0; retry < 3; retry++) {
1062 * If retrying, reset the drive.
1065 v86.ctl = V86_FLAGS;
1068 v86.edx = od->od_unit;
1073 * Always use EDD if the disk supports it, otherwise fall back
1074 * to CHS mode (returning an error if the cylinder number is
1077 if (od->od_flags & BD_MODEEDD1) {
1078 static unsigned short packet[8];
1082 packet[2] = VTOPOFF(xp);
1083 packet[3] = VTOPSEG(xp);
1084 packet[4] = dblk & 0xffff;
1085 packet[5] = dblk >> 16;
1088 v86.ctl = V86_FLAGS;
1091 v86.edx = od->od_unit;
1092 v86.ds = VTOPSEG(packet);
1093 v86.esi = VTOPOFF(packet);
1095 result = (v86.efl & 0x1);
1098 } else if (cyl < 1024) {
1099 /* Use normal CHS addressing */
1100 v86.ctl = V86_FLAGS;
1102 v86.eax = 0x200 | x;
1103 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1104 v86.edx = (hd << 8) | od->od_unit;
1105 v86.es = VTOPSEG(xp);
1106 v86.ebx = VTOPOFF(xp);
1108 result = (v86.efl & 0x1);
1117 DEBUG("%d sectors from %d/%d/%d to %p (0x%x) %s", x, cyl, hd, sec - 1, p, VTOP(p), result ? "failed" : "ok");
1118 /* BUG here, cannot use v86 in printf because putchar uses it too */
1119 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x",
1120 0x200 | x, ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec, (hd << 8) | od->od_unit, (v86.eax >> 8) & 0xff);
1127 bcopy(breg, p, x * BIOSDISK_SECSIZE);
1128 p += (x * BIOSDISK_SECSIZE);
1133 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1141 bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1143 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer;
1144 caddr_t p, xp, bbuf, breg;
1146 /* Just in case some idiot actually tries to read -1 blocks... */
1150 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1154 /* Decide whether we have to bounce */
1155 if ((od->od_unit < 0x80) &&
1156 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16))) {
1159 * There is a 64k physical boundary somewhere in the destination buffer, so we have
1160 * to arrange a suitable bounce buffer. Allocate a buffer twice as large as we
1161 * need to. Use the bottom half unless there is a break there, in which case we
1165 x = min(FLOPPY_BOUNCEBUF, (unsigned)blks);
1166 bbuf = malloc(x * 2 * BIOSDISK_SECSIZE);
1167 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) == ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) {
1170 breg = bbuf + x * BIOSDISK_SECSIZE;
1172 maxfer = x; /* limit transfers to bounce region size */
1180 cyl = x / bpc; /* block # / blocks per cylinder */
1181 x %= bpc; /* block offset into cylinder */
1182 hd = x / od->od_sec; /* offset / blocks per track */
1183 sec = x % od->od_sec; /* offset into track */
1185 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */
1186 x = szmin(od->od_sec - sec, resid);
1188 x = szmin(x, maxfer); /* fit bounce buffer */
1190 /* where do we transfer to? */
1191 xp = bbuf == NULL ? p : breg;
1193 /* correct sector number for 1-based BIOS numbering */
1197 /* Put your Data In, Put your Data out,
1198 Put your Data In, and shake it all about
1201 bcopy(p, breg, x * BIOSDISK_SECSIZE);
1202 p += (x * BIOSDISK_SECSIZE);
1207 * Loop retrying the operation a couple of times. The BIOS may also
1210 for (retry = 0; retry < 3; retry++) {
1212 * If retrying, reset the drive.
1215 v86.ctl = V86_FLAGS;
1218 v86.edx = od->od_unit;
1223 * Always use EDD if the disk supports it, otherwise fall back
1224 * to CHS mode (returning an error if the cylinder number is
1227 if (od->od_flags & BD_MODEEDD1) {
1228 static unsigned short packet[8];
1232 packet[2] = VTOPOFF(xp);
1233 packet[3] = VTOPSEG(xp);
1234 packet[4] = dblk & 0xffff;
1235 packet[5] = dblk >> 16;
1238 v86.ctl = V86_FLAGS;
1240 /* Should we Write with verify ?? 0x4302 ? */
1242 v86.edx = od->od_unit;
1243 v86.ds = VTOPSEG(packet);
1244 v86.esi = VTOPOFF(packet);
1246 result = (v86.efl & 0x1);
1249 } else if (cyl < 1024) {
1250 /* Use normal CHS addressing */
1251 v86.ctl = V86_FLAGS;
1253 v86.eax = 0x300 | x;
1254 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1255 v86.edx = (hd << 8) | od->od_unit;
1256 v86.es = VTOPSEG(xp);
1257 v86.ebx = VTOPOFF(xp);
1259 result = (v86.efl & 0x1);
1268 DEBUG("%d sectors from %d/%d/%d to %p (0x%x) %s", x, cyl, hd, sec - 1, p, VTOP(p), result ? "failed" : "ok");
1269 /* BUG here, cannot use v86 in printf because putchar uses it too */
1270 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x",
1271 0x200 | x, ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec, (hd << 8) | od->od_unit, (v86.eax >> 8) & 0xff);
1279 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1285 bd_getgeom(struct open_disk *od)
1288 v86.ctl = V86_FLAGS;
1291 v86.edx = od->od_unit;
1294 if ((v86.efl & 0x1) || /* carry set */
1295 ((v86.edx & 0xff) <= (unsigned)(od->od_unit & 0x7f))) /* unit # bad */
1298 /* convert max cyl # -> # of cylinders */
1299 od->od_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1;
1300 /* convert max head # -> # of heads */
1301 od->od_hds = ((v86.edx & 0xff00) >> 8) + 1;
1302 od->od_sec = v86.ecx & 0x3f;
1304 DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec);
1309 * Return the BIOS geometry of a given "fixed drive" in a format
1310 * suitable for the legacy bootinfo structure. Since the kernel is
1311 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we
1312 * prefer to get the information directly, rather than rely on being
1313 * able to put it together from information already maintained for
1314 * different purposes and for a probably different number of drives.
1316 * For valid drives, the geometry is expected in the format (31..0)
1317 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are
1318 * indicated by returning the geometry of a "1.2M" PC-format floppy
1319 * disk. And, incidentally, what is returned is not the geometry as
1320 * such but the highest valid cylinder, head, and sector numbers.
1323 bd_getbigeom(int bunit)
1326 v86.ctl = V86_FLAGS;
1329 v86.edx = 0x80 + bunit;
1333 return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
1334 (v86.edx & 0xff00) | (v86.ecx & 0x3f);
1338 * Return a suitable cdev_t value for (dev).
1340 * In the case where it looks like (dev) is a SCSI disk, we allow the number of
1341 * IDE disks to be specified in $num_ide_disks. There should be a Better Way.
1344 bd_getdev(struct i386_devdesc *dev)
1346 struct open_disk *od;
1351 int unitofs = 0, i, unit;
1353 biosdev = bd_unit2bios(dev->d_kind.biosdisk.unit);
1354 DEBUG("unit %d BIOS device %d", dev->d_kind.biosdisk.unit, biosdev);
1355 if (biosdev == -1) /* not a BIOS device */
1357 if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */
1360 if (biosdev < 0x80) {
1361 /* floppy (or emulated floppy) or ATAPI device */
1362 if (bdinfo[dev->d_kind.biosdisk.unit].bd_type == DT_ATAPI) {
1363 /* is an ATAPI disk */
1366 /* is a floppy disk */
1371 if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) {
1372 /* label OK, disk labelled as SCSI */
1374 /* check for unit number correction hint, now deprecated */
1375 if ((nip = getenv("num_ide_disks")) != NULL) {
1376 i = strtol(nip, &cp, 0);
1377 /* check for parse error */
1378 if ((cp != nip) && (*cp == 0))
1382 /* assume an IDE disk */
1386 /* default root disk unit number */
1387 unit = (biosdev & 0x7f) - unitofs;
1389 /* XXX a better kludge to set the root disk unit number */
1390 if ((nip = getenv("root_disk_unit")) != NULL) {
1391 i = strtol(nip, &cp, 0);
1392 /* check for parse error */
1393 if ((cp != nip) && (*cp == 0))
1397 rootdev = MAKEBOOTDEV(major,
1398 (dev->d_kind.biosdisk.slice + 1) >> 4, /* XXX slices may be wrong here */
1399 (dev->d_kind.biosdisk.slice + 1) & 0xf,
1401 dev->d_kind.biosdisk.partition);
1402 DEBUG("dev is 0x%x\n", rootdev);