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,
145 char bounce_base[BOUNCEBUF_SIZE]; /* also used by CD code */
149 * Translate between BIOS device numbers and our private unit numbers.
152 bd_bios2unit(int biosdev)
156 DEBUG("looking for bios device 0x%x", biosdev);
157 for (i = 0; i < nbdinfo; i++) {
158 DEBUG("bd unit %d is BIOS device 0x%x", i, bdinfo[i].bd_unit);
159 if (bdinfo[i].bd_unit == biosdev)
166 bd_unit2bios(int unit)
168 if ((unit >= 0) && (unit < nbdinfo))
169 return(bdinfo[unit].bd_unit);
174 * Quiz the BIOS for disk devices, save a little info about them.
179 int base, unit, nfd = 0;
181 /* sequence 0, 0x80 */
182 for (base = 0; base <= 0x80; base += 0x80) {
183 for (unit = base; (nbdinfo < MAXBDDEV); unit++) {
184 /* check the BIOS equipment list for number of fixed disks */
186 (nfd >= *(unsigned char *)PTOV(BIOS_NUMDRIVES)))
189 bdinfo[nbdinfo].bd_unit = unit;
190 bdinfo[nbdinfo].bd_flags = (unit < 0x80) ? BD_FLOPPY : 0;
192 if (!bd_int13probe(&bdinfo[nbdinfo]))
195 /* XXX we need "disk aliases" to make this simpler */
196 printf("BIOS drive %c: is disk%d\n",
197 (unit < 0x80) ? ('A' + unit) : ('C' + unit - 0x80), nbdinfo);
207 * Try to detect a device supported by the legacy int13 BIOS
210 bd_int13probe(struct bdinfo *bd)
215 v86.edx = bd->bd_unit;
218 if (!(v86.efl & 0x1) && /* carry clear */
219 ((v86.edx & 0xff) > ((unsigned)bd->bd_unit & 0x7f))) { /* unit # OK */
222 * Ignore devices with an absurd sector size.
224 if ((v86.ecx & 0x3f) == 0) {
225 DEBUG("Invalid geometry for unit %d", bd->bd_unit);
228 bd->bd_flags |= BD_MODEINT13;
229 bd->bd_type = v86.ebx & 0xff;
231 /* Determine if we can use EDD with this device. */
235 v86.edx = bd->bd_unit;
238 if (!(v86.efl & 0x1) && /* carry clear */
239 ((v86.ebx & 0xffff) == 0xaa55) && /* signature */
240 (v86.ecx & 0x1)) { /* packets mode ok */
241 bd->bd_flags |= BD_MODEEDD1;
242 if((v86.eax & 0xff00) > 0x300)
243 bd->bd_flags |= BD_MODEEDD3;
251 * Print information about disks
254 bd_print(int verbose)
258 struct i386_devdesc dev;
259 struct open_disk *od;
260 struct dos_partition *dptr;
262 for (i = 0; i < nbdinfo; i++) {
263 sprintf(line, " disk%d: BIOS drive %c:\n", i,
264 (bdinfo[i].bd_unit < 0x80) ? ('A' + bdinfo[i].bd_unit) : ('C' + bdinfo[i].bd_unit - 0x80));
267 /* try to open the whole disk */
268 dev.d_kind.biosdisk.unit = i;
269 dev.d_kind.biosdisk.slice = -1;
270 dev.d_kind.biosdisk.partition = -1;
272 if (!bd_opendisk(&od, &dev)) {
274 /* Do we have a partition table? */
275 if (od->od_flags & BD_PARTTABOK) {
276 dptr = &od->od_slicetab[0];
278 /* Check for a "dedicated" disk */
279 if (((dptr[3].dp_typ == DOSPTYP_386BSD) ||
280 (dptr[3].dp_typ == DOSPTYP_NETBSD)) &&
281 (dptr[3].dp_start == 0) &&
282 (dptr[3].dp_size == 50000)) {
283 sprintf(line, " disk%d", i);
284 bd_printbsdslice(od, 0, line, verbose);
286 for (j = 0; j < od->od_nslices; j++) {
287 sprintf(line, " disk%ds%d", i, j + 1);
288 bd_printslice(od, &dptr[j], line, verbose);
298 * Print information about slices on a disk. For the size calculations we
299 * assume a 512 byte sector.
302 bd_printslice(struct open_disk *od, struct dos_partition *dp, char *prefix,
307 switch (dp->dp_typ) {
310 /* XXX: possibly add types 0 and 1, as in subr_disk, for gpt magic */
311 bd_printbsdslice(od, (daddr_t)dp->dp_start, prefix, verbose);
315 sprintf(line, "%s: Linux swap %.6dMB (%d - %d)\n",
316 prefix, dp->dp_size / 2048,
317 dp->dp_start, dp->dp_start + dp->dp_size);
319 sprintf(line, "%s: Linux swap\n", prefix);
324 * read the superblock to confirm this is an ext2fs partition?
327 sprintf(line, "%s: ext2fs %.6dMB (%d - %d)\n", prefix,
328 dp->dp_size / 2048, dp->dp_start,
329 dp->dp_start + dp->dp_size);
331 sprintf(line, "%s: ext2fs\n", prefix);
333 case 0x00: /* unused partition */
338 sprintf(line, "%s: FAT-12 %.6dMB (%d - %d)\n", prefix,
339 dp->dp_size / 2048, dp->dp_start,
340 dp->dp_start + dp->dp_size);
342 sprintf(line, "%s: FAT-12\n", prefix);
348 sprintf(line, "%s: FAT-16 %.6dMB (%d - %d)\n", prefix,
349 dp->dp_size / 2048, dp->dp_start,
350 dp->dp_start + dp->dp_size);
352 sprintf(line, "%s: FAT-16\n", prefix);
357 sprintf(line, "%s: FAT-32 %.6dMB (%d - %d)\n", prefix,
358 dp->dp_size / 2048, dp->dp_start,
359 dp->dp_start + dp->dp_size);
361 sprintf(line, "%s: FAT-32\n", prefix);
365 sprintf(line, "%s: Unknown fs: 0x%x %.6dMB (%d - %d)\n",
366 prefix, dp->dp_typ, dp->dp_size / 2048,
367 dp->dp_start, dp->dp_start + dp->dp_size);
369 sprintf(line, "%s: Unknown fs: 0x%x\n", prefix,
376 print_partition(u_int8_t fstype, unsigned long long offset,
377 unsigned long long size, int i, int od_flags,
378 char *prefix, int verbose, int type)
383 * For each partition, make sure we know what type of fs it is. If
384 * not, then skip it. However, since floppies often have bogus
385 * fstypes, print the 'a' partition on a floppy even if it is marked
388 if ((fstype == FS_SWAP) ||
389 (fstype == FS_VINUM) ||
390 (fstype == FS_HAMMER) ||
391 (fstype == FS_HAMMER2) ||
392 (fstype == FS_BSDFFS) ||
393 (fstype == FS_ZFS) ||
394 (fstype == FS_JFS2) ||
395 ((fstype == FS_UNUSED) &&
396 (od_flags & BD_FLOPPY) && (i == 0))) {
398 /* Only print out statistics in verbose mode */
400 sprintf(line, "%c %s%c: %s %.6lluMB (%llu - %llu)\n",
401 /* prefix disks that can be used to load modules with '*' */
402 ((fstype == FS_BSDFFS) || (fstype == FS_UNUSED) ||
403 (fstype == FS_VINUM)) ? '*' : ' ',
405 (fstype == FS_SWAP) ? "swap" :
406 (fstype == FS_VINUM) ? "vinum" :
407 (fstype == FS_HAMMER) ? "HAMMER" :
408 (fstype == FS_HAMMER2) ? "HAMMER2" :
409 (fstype == FS_JFS2) ? "JFS2" :
410 (fstype == FS_ZFS) ? "ZFS" :
411 (fstype == FS_BSDFFS) ? "FFS" :
413 (type==32)?(size / 2048):(size/1024/1024),
417 sprintf(line, "%c %s%c: %s\n",
418 /* prefix disks that can be used to load modules with '*' */
419 ((fstype == FS_BSDFFS) || (fstype == FS_UNUSED) ||
420 (fstype == FS_VINUM)) ? '*' : ' ',
422 (fstype == FS_SWAP) ? "swap" :
423 (fstype == FS_VINUM) ? "vinum" :
424 (fstype == FS_HAMMER) ? "HAMMER" :
425 (fstype == FS_HAMMER2) ? "HAMMER2" :
426 (fstype == FS_JFS2) ? "JFS2" :
427 (fstype == FS_ZFS) ? "ZFS" :
428 (fstype == FS_BSDFFS) ? "FFS" :
437 * Print out each valid partition in the disklabel of a FreeBSD slice.
438 * For size calculations, we assume a 512 byte sector size.
441 bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix,
445 char buf[BIOSDISK_SECSIZE*2];
446 struct disklabel32 *lp = NULL;
447 struct disklabel64 *lp64 = NULL;
451 if (bd_read(od, offset + LABELSECTOR32, 1, buf))
453 lp =(struct disklabel32 *)(&buf[0]);
454 if (lp->d_magic != DISKMAGIC32) {
455 if (bd_read(od, offset, 2, buf))
458 lp64 =(struct disklabel64 *)(&buf[0]);
459 if (lp64->d_magic != DISKMAGIC64) {
460 sprintf(line, "%s: bad disklabel\n", prefix);
464 lp = NULL; /* PARANOID */
467 /* We got ourselves a disklabel64 here */
468 for (i = 0; i < lp64->d_npartitions; i++) {
469 if (lp64->d_partitions[i].p_bsize == 0)
472 print_partition(lp64->d_partitions[i].p_fstype,
473 lp64->d_partitions[i].p_boffset,
474 lp64->d_partitions[i].p_bsize,
475 i, od->od_flags, prefix, verbose, 64);
478 /* Print partitions */
479 for (i = 0; i < lp->d_npartitions; i++) {
480 print_partition(lp->d_partitions[i].p_fstype,
481 lp->d_partitions[i].p_offset,
482 lp->d_partitions[i].p_size,
483 i, od->od_flags, prefix, verbose, 32);
490 * Attempt to open the disk described by (dev) for use by (f).
492 * Note that the philosophy here is "give them exactly what
493 * they ask for". This is necessary because being too "smart"
494 * about what the user might want leads to complications.
495 * (eg. given no slice or partition value, with a disk that is
496 * sliced - are they after the first BSD slice, or the DOS
500 bd_open(struct open_file *f, ...)
503 struct i386_devdesc *dev;
504 struct open_disk *od;
508 dev = va_arg(ap, struct i386_devdesc *);
510 if ((error = bd_opendisk(&od, dev)))
516 ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od;
517 DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff);
522 bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev)
524 struct dos_partition *dptr;
525 struct disklabel32 *lp;
526 struct disklabel64 *lp64;
527 struct open_disk *od;
528 int sector, slice, i;
530 static char buf[BUFSIZE];
532 if (dev->d_kind.biosdisk.unit >= nbdinfo) {
533 DEBUG("attempt to open nonexistent disk");
537 od = (struct open_disk *)malloc(sizeof(struct open_disk));
543 /* Look up BIOS unit number, intialise open_disk structure */
544 od->od_dkunit = dev->d_kind.biosdisk.unit;
545 od->od_unit = bdinfo[od->od_dkunit].bd_unit;
546 od->od_flags = bdinfo[od->od_dkunit].bd_flags;
550 DEBUG("open '%s', unit 0x%x slice %d partition %c",
551 i386_fmtdev(dev), dev->d_kind.biosdisk.unit,
552 dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition + 'a');
554 /* Get geometry for this open (removable device may have changed) */
555 if (bd_getgeom(od)) {
556 DEBUG("can't get geometry");
562 * Following calculations attempt to determine the correct value
563 * for d->od_boff by looking for the slice and partition specified,
564 * or searching for reasonable defaults.
568 * Find the slice in the DOS slice table.
570 if (bd_read(od, 0, 1, buf)) {
571 DEBUG("error reading MBR");
577 * Check the slice table magic.
579 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
580 /* If a slice number was explicitly supplied, this is an error */
581 if (dev->d_kind.biosdisk.slice > 0) {
582 DEBUG("no slice table/MBR (no magic)");
587 goto unsliced; /* may be a floppy */
591 * copy the partition table, then pick up any extended partitions. The
592 * base partition table always has four entries, even if some of them
593 * represented extended partitions. However, any additional sub-extended
594 * partitions will be silently recursed and not included in the slice
597 bcopy(buf + DOSPARTOFF, &od->od_slicetab,
598 sizeof(struct dos_partition) * NDOSPART);
599 od->od_nslices = NDOSPART;
601 dptr = &od->od_slicetab[0];
602 for (i = 0; i < NDOSPART; i++, dptr++) {
603 if ((dptr->dp_typ == DOSPTYP_EXT) || (dptr->dp_typ == DOSPTYP_EXTLBA))
604 bd_chainextended(od, dptr->dp_start, 0); /* 1st offset is zero */
606 od->od_flags |= BD_PARTTABOK;
607 dptr = &od->od_slicetab[0];
610 * Overflow entries are not loaded into memory but we still keep
611 * track of the count. Fix it up now.
613 if (od->od_nslices > NEXTDOSPART)
614 od->od_nslices = NEXTDOSPART;
617 * Is this a request for the whole disk?
619 if (dev->d_kind.biosdisk.slice == -1) {
625 * if a slice number was supplied but not found, this is an error.
627 if (dev->d_kind.biosdisk.slice > 0) {
628 slice = dev->d_kind.biosdisk.slice - 1;
629 if (slice >= od->od_nslices) {
630 DEBUG("slice %d not found", slice);
637 * Check for the historically bogus MBR found on true dedicated disks
639 if ((dptr[3].dp_typ == DOSPTYP_386BSD) &&
640 (dptr[3].dp_start == 0) &&
641 (dptr[3].dp_size == 50000)) {
646 /* Try to auto-detect the best slice; this should always give a slice number */
647 if (dev->d_kind.biosdisk.slice == 0) {
648 slice = bd_bestslice(od);
653 dev->d_kind.biosdisk.slice = slice;
656 dptr = &od->od_slicetab[0];
658 * Accept the supplied slice number unequivocally (we may be looking
659 * at a DOS partition).
661 dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */
662 sector = dptr->dp_start;
663 DEBUG("slice entry %d at %d, %d sectors", dev->d_kind.biosdisk.slice - 1, sector, dptr->dp_size);
666 * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition
668 if ((dptr->dp_typ == DOSPTYP_386BSD) && (dev->d_kind.biosdisk.partition < 0))
669 dev->d_kind.biosdisk.partition = 0;
673 * Now we have the slice offset, look for the partition in the disklabel if we have
674 * a partition to start with.
676 * XXX we might want to check the label checksum.
678 if (dev->d_kind.biosdisk.partition < 0) {
679 od->od_boff = sector; /* no partition, must be after the slice */
680 DEBUG("opening raw slice");
683 if (bd_read(od, sector + LABELSECTOR32, 1, buf)) {
684 DEBUG("error reading disklabel");
688 DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel32), buf + LABELOFFSET32, &od->od_disklabel);
689 bcopy(buf + LABELOFFSET32, &od->od_disklabel, sizeof(struct disklabel32));
690 lp = &od->od_disklabel;
692 if (lp->d_magic == DISKMAGIC32) {
693 od->od_flags |= BD_LABELOK;
695 if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) {
696 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
697 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions);
704 /* Complain if the partition is unused unless this is a floppy. */
705 if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) &&
706 !(od->od_flags & BD_FLOPPY))
707 DEBUG("warning, partition marked as unused");
711 lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset -
712 lp->d_partitions[RAW_PART].p_offset +
718 /* else maybe DISKLABEL64? */
720 if (bd_read(od, sector, (sizeof(od->od_disklabel64) + 511) / 512, buf)) {
721 DEBUG("error reading disklabel");
725 DEBUG("copy %d bytes of label from %p to %p", sizeof(od->od_disklabel64), buf, &od->od_disklabel64);
726 bcopy(buf, &od->od_disklabel64, sizeof(od->od_disklabel64));
727 lp64 = &od->od_disklabel64;
729 if (lp64->d_magic == DISKMAGIC64) {
730 od->od_flags |= BD_LABELOK;
732 if (dev->d_kind.biosdisk.partition >= lp64->d_npartitions ||
733 lp64->d_partitions[dev->d_kind.biosdisk.partition].p_bsize == 0) {
734 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
735 'a' + dev->d_kind.biosdisk.partition, 'a' + lp64->d_npartitions);
742 lp64->d_partitions[dev->d_kind.biosdisk.partition].p_boffset / 512 +
745 DEBUG("disklabel64 slice at %d", od->od_boff);
748 DEBUG("no disklabel");
757 *odp = od; /* return the open disk */
764 bd_chainextended(struct open_disk *od, u_int32_t base, u_int32_t offset)
766 char buf[BIOSDISK_SECSIZE];
767 struct dos_partition *dp1, *dp2;
770 if (bd_read(od, (daddr_t)(base + offset), 1, buf)) {
771 printf("\nerror reading extended partition table");
776 * dp1 points to the first record in the on-disk XPT,
777 * dp2 points to the next entry in the in-memory parition table.
779 * NOTE: dp2 may be out of bounds if od_nslices >= NEXTDOSPART.
781 * NOTE: unlike the extended partitions in our primary dos partition
782 * table, we do not record recursed extended partitions themselves
783 * in our in-memory partition table.
785 * NOTE: recording within our in-memory table must be breadth first
786 * ot match what the kernel does. Thus, two passes are required.
788 * NOTE: partitioning programs which support extended partitions seem
789 * to always use the first entry for the user partition and the
790 * second entry to chain, and also appear to disallow more then one
791 * extended partition at each level. Nevertheless we make our code
792 * somewhat more generic (and the same as the kernel's own slice
795 dp1 = (struct dos_partition *)(&buf[DOSPARTOFF]);
796 dp2 = &od->od_slicetab[od->od_nslices];
798 for (i = 0; i < NDOSPART; ++i, ++dp1) {
799 if (dp1->dp_scyl == 0 && dp1->dp_shd == 0 &&
800 dp1->dp_ssect == 0 && dp1->dp_start == 0 &&
804 if ((dp1->dp_typ == DOSPTYP_EXT) ||
805 (dp1->dp_typ == DOSPTYP_EXTLBA)) {
807 * breadth first traversal, must skip in the
814 * Only load up the in-memory data if we haven't overflowed
815 * our in-memory array.
817 if (od->od_nslices < NEXTDOSPART) {
818 dp2->dp_typ = dp1->dp_typ;
819 dp2->dp_start = base + offset + dp1->dp_start;
820 dp2->dp_size = dp1->dp_size;
827 * Pass 2 - handle extended partitions. Note that the extended
828 * slice itself is not stored in the slice array when we recurse,
829 * but any 'original' top-level extended slices are. This is to
830 * match what the kernel does.
833 for (i = 0; i < NDOSPART; ++i, ++dp1) {
834 if (dp1->dp_scyl == 0 && dp1->dp_shd == 0 &&
835 dp1->dp_ssect == 0 && dp1->dp_start == 0 &&
839 if ((dp1->dp_typ == DOSPTYP_EXT) ||
840 (dp1->dp_typ == DOSPTYP_EXTLBA))
841 bd_chainextended(od, base, dp1->dp_start);
846 * Search for a slice with the following preferences:
848 * 1: Active FreeBSD slice
849 * 2: Non-active FreeBSD slice
850 * 3: Active Linux slice
851 * 4: non-active Linux slice
852 * 5: Active FAT/FAT32 slice
853 * 6: non-active FAT/FAT32 slice
855 #define PREF_RAWDISK 0
856 #define PREF_FBSD_ACT 1
858 #define PREF_LINUX_ACT 3
860 #define PREF_DOS_ACT 5
865 * slicelimit is in the range 0 .. NDOSPART
868 bd_bestslice(struct open_disk *od)
870 struct dos_partition *dp;
875 preflevel = PREF_NONE;
877 dp = &od->od_slicetab[0];
878 for (i = 0; i < od->od_nslices; i++, dp++) {
879 switch (dp->dp_typ) {
880 case DOSPTYP_386BSD: /* FreeBSD */
881 pref = dp->dp_flag & 0x80 ? PREF_FBSD_ACT : PREF_FBSD;
885 pref = dp->dp_flag & 0x80 ? PREF_LINUX_ACT : PREF_LINUX;
888 case 0x01: /* DOS/Windows */
894 pref = dp->dp_flag & 0x80 ? PREF_DOS_ACT : PREF_DOS;
900 if (pref < preflevel) {
909 bd_close(struct open_file *f)
911 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data);
918 bd_closedisk(struct open_disk *od)
920 DEBUG("open_disk %p", od);
922 /* XXX is this required? (especially if disk already open...) */
923 if (od->od_flags & BD_FLOPPY)
930 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
932 struct bcache_devdata bcd;
933 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
935 bcd.dv_strategy = bd_realstrategy;
936 bcd.dv_devdata = devdata;
937 return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize));
941 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
943 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
945 #ifdef BD_SUPPORT_FRAGS
946 char fragbuf[BIOSDISK_SECSIZE];
949 fragsize = size % BIOSDISK_SECSIZE;
951 if (size % BIOSDISK_SECSIZE)
952 panic("bd_strategy: %d bytes I/O not multiple of block size", size);
955 DEBUG("open_disk %p", od);
959 blks = size / BIOSDISK_SECSIZE;
960 DEBUG("read %d from %d to %p", blks, dblk, buf);
964 if (blks && bd_read(od, dblk, blks, buf)) {
968 #ifdef BD_SUPPORT_FRAGS
969 DEBUG("bd_strategy: frag read %d from %d+%d to %p",
970 fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE));
971 if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) {
972 DEBUG("frag read error");
975 bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize);
981 blks = size / BIOSDISK_SECSIZE;
982 DEBUG("write %d from %d to %p", blks, dblk, buf);
986 if (blks && bd_write(od, dblk, blks, buf)) {
987 DEBUG("write error");
990 #ifdef BD_SUPPORT_FRAGS
992 DEBUG("Attempted to write a frag");
1000 break; /* DO NOTHING */
1006 bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1008 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer;
1009 caddr_t p, xp, bbuf, breg;
1011 /* Just in case some idiot actually tries to read -1 blocks... */
1015 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1020 * Always bounce. Our buffer is probably not segment-addressable.
1025 * There is a 64k physical boundary somewhere in the destination
1026 * buffer, so we have to arrange a suitable bounce buffer. Allocate
1027 * a buffer twice as large as we need to. Use the bottom half unless
1028 * there is a break there, in which case we use the top half.
1031 x = min(BOUNCEBUF_SECTS, (unsigned)blks);
1033 if (((u_int32_t)VTOP(bbuf) & 0xffff8000) ==
1034 ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE - 1) & 0xffff8000)) {
1037 breg = bbuf + x * BIOSDISK_SECSIZE;
1039 maxfer = x; /* limit transfers to bounce region size */
1047 cyl = x / bpc; /* block # / blocks per cylinder */
1048 x %= bpc; /* block offset into cylinder */
1049 hd = x / od->od_sec; /* offset / blocks per track */
1050 sec = x % od->od_sec; /* offset into track */
1052 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */
1053 x = szmin(od->od_sec - sec, resid);
1055 x = min(x, maxfer); /* fit bounce buffer */
1057 /* where do we transfer to? */
1058 xp = (bbuf == NULL ? p : breg);
1060 /* correct sector number for 1-based BIOS numbering */
1064 * Loop retrying the operation a couple of times. The BIOS may also
1067 for (retry = 0; retry < 3; retry++) {
1069 * If retrying, reset the drive.
1072 v86.ctl = V86_FLAGS;
1075 v86.edx = od->od_unit;
1080 * Always use EDD if the disk supports it, otherwise fall back
1081 * to CHS mode (returning an error if the cylinder number is
1084 if (od->od_flags & BD_MODEEDD1) {
1085 static unsigned short packet[8];
1089 packet[2] = VTOPOFF(xp);
1090 packet[3] = VTOPSEG(xp);
1091 packet[4] = dblk & 0xffff;
1092 packet[5] = dblk >> 16;
1095 v86.ctl = V86_FLAGS;
1098 v86.edx = od->od_unit;
1099 v86.ds = VTOPSEG(packet);
1100 v86.esi = VTOPOFF(packet);
1102 result = (v86.efl & 0x1);
1105 } else if (cyl < 1024) {
1106 /* Use normal CHS addressing */
1107 v86.ctl = V86_FLAGS;
1109 v86.eax = 0x200 | x;
1110 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1111 v86.edx = (hd << 8) | od->od_unit;
1112 v86.es = VTOPSEG(xp);
1113 v86.ebx = VTOPOFF(xp);
1115 result = (v86.efl & 0x1);
1124 DEBUG("%u sectors from %u/%u/%d to %p (0x%x) %s",
1125 x, cyl, hd, sec - 1, p, VTOP(p), result ? "failed" : "ok");
1126 /* BUG here, cannot use v86 in printf because putchar uses it too */
1127 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x",
1129 ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec,
1130 (hd << 8) | od->od_unit,
1131 (v86.eax >> 8) & 0xff);
1135 bcopy(breg, p, x * BIOSDISK_SECSIZE);
1136 p += (x * BIOSDISK_SECSIZE);
1141 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1147 bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1149 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer;
1150 caddr_t p, xp, bbuf, breg;
1152 /* Just in case some idiot actually tries to read -1 blocks... */
1156 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1161 * Always bounce. Our buffer is probably not segment-addressable.
1165 * There is a 64k physical boundary somewhere in the destination
1166 * buffer, so we have to arrange a suitable bounce buffer. Allocate
1167 * a buffer twice as large as we need to. Use the bottom half
1168 * unless there is a break there, in which case we use the top half.
1171 x = min(BOUNCEBUF_SECTS, (unsigned)blks);
1173 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) ==
1174 ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE - 1) & 0xffff0000)) {
1177 breg = bbuf + x * BIOSDISK_SECSIZE;
1179 maxfer = x; /* limit transfers to bounce region size */
1187 cyl = x / bpc; /* block # / blocks per cylinder */
1188 x %= bpc; /* block offset into cylinder */
1189 hd = x / od->od_sec; /* offset / blocks per track */
1190 sec = x % od->od_sec; /* offset into track */
1192 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */
1193 x = szmin(od->od_sec - sec, resid);
1195 x = szmin(x, maxfer); /* fit bounce buffer */
1197 /* where do we transfer to? */
1198 xp = (bbuf == NULL ? p : breg);
1200 /* correct sector number for 1-based BIOS numbering */
1204 /* Put your Data In, Put your Data out,
1205 Put your Data In, and shake it all about
1208 bcopy(p, breg, x * BIOSDISK_SECSIZE);
1209 p += (x * BIOSDISK_SECSIZE);
1214 * Loop retrying the operation a couple of times. The BIOS may also
1217 for (retry = 0; retry < 3; retry++) {
1219 * If retrying, reset the drive.
1222 v86.ctl = V86_FLAGS;
1225 v86.edx = od->od_unit;
1230 * Always use EDD if the disk supports it, otherwise fall back
1231 * to CHS mode (returning an error if the cylinder number is
1234 if (od->od_flags & BD_MODEEDD1) {
1235 static unsigned short packet[8];
1239 packet[2] = VTOPOFF(xp);
1240 packet[3] = VTOPSEG(xp);
1241 packet[4] = dblk & 0xffff;
1242 packet[5] = dblk >> 16;
1245 v86.ctl = V86_FLAGS;
1247 /* Should we Write with verify ?? 0x4302 ? */
1249 v86.edx = od->od_unit;
1250 v86.ds = VTOPSEG(packet);
1251 v86.esi = VTOPOFF(packet);
1253 result = (v86.efl & 0x1);
1256 } else if (cyl < 1024) {
1257 /* Use normal CHS addressing */
1258 v86.ctl = V86_FLAGS;
1260 v86.eax = 0x300 | x;
1261 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1262 v86.edx = (hd << 8) | od->od_unit;
1263 v86.es = VTOPSEG(xp);
1264 v86.ebx = VTOPOFF(xp);
1266 result = (v86.efl & 0x1);
1275 DEBUG("%u sectors from %u/%u/%d to %p (0x%x) %s", x, cyl, hd, sec - 1, p, VTOP(p), result ? "failed" : "ok");
1276 /* BUG here, cannot use v86 in printf because putchar uses it too */
1277 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x",
1278 0x200 | x, ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec, (hd << 8) | od->od_unit, (v86.eax >> 8) & 0xff);
1283 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1287 bd_getgeom(struct open_disk *od)
1290 v86.ctl = V86_FLAGS;
1293 v86.edx = od->od_unit;
1296 if ((v86.efl & 0x1) || /* carry set */
1297 ((v86.edx & 0xff) <= (unsigned)(od->od_unit & 0x7f))) /* unit # bad */
1300 /* convert max cyl # -> # of cylinders */
1301 od->od_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1;
1302 /* convert max head # -> # of heads */
1303 od->od_hds = ((v86.edx & 0xff00) >> 8) + 1;
1304 od->od_sec = v86.ecx & 0x3f;
1306 DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec);
1311 * Return the BIOS geometry of a given "fixed drive" in a format
1312 * suitable for the legacy bootinfo structure. Since the kernel is
1313 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we
1314 * prefer to get the information directly, rather than rely on being
1315 * able to put it together from information already maintained for
1316 * different purposes and for a probably different number of drives.
1318 * For valid drives, the geometry is expected in the format (31..0)
1319 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are
1320 * indicated by returning the geometry of a "1.2M" PC-format floppy
1321 * disk. And, incidentally, what is returned is not the geometry as
1322 * such but the highest valid cylinder, head, and sector numbers.
1325 bd_getbigeom(int bunit)
1328 v86.ctl = V86_FLAGS;
1331 v86.edx = 0x80 + bunit;
1335 return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
1336 (v86.edx & 0xff00) | (v86.ecx & 0x3f);
1340 * Return a suitable cdev_t value for (dev).
1342 * In the case where it looks like (dev) is a SCSI disk, we allow the number of
1343 * IDE disks to be specified in $num_ide_disks. There should be a Better Way.
1346 bd_getdev(struct i386_devdesc *dev)
1348 struct open_disk *od;
1353 int unitofs = 0, i, unit;
1355 biosdev = bd_unit2bios(dev->d_kind.biosdisk.unit);
1356 DEBUG("unit %d BIOS device %d", dev->d_kind.biosdisk.unit, biosdev);
1357 if (biosdev == -1) /* not a BIOS device */
1359 if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */
1362 if (biosdev < 0x80) {
1363 /* floppy (or emulated floppy) or ATAPI device */
1364 if (bdinfo[dev->d_kind.biosdisk.unit].bd_type == DT_ATAPI) {
1365 /* is an ATAPI disk */
1368 /* is a floppy disk */
1373 if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) {
1374 /* label OK, disk labelled as SCSI */
1376 /* check for unit number correction hint, now deprecated */
1377 if ((nip = getenv("num_ide_disks")) != NULL) {
1378 i = strtol(nip, &cp, 0);
1379 /* check for parse error */
1380 if ((cp != nip) && (*cp == 0))
1384 /* assume an IDE disk */
1388 /* default root disk unit number */
1389 unit = (biosdev & 0x7f) - unitofs;
1391 /* XXX a better kludge to set the root disk unit number */
1392 if ((nip = getenv("root_disk_unit")) != NULL) {
1393 i = strtol(nip, &cp, 0);
1394 /* check for parse error */
1395 if ((cp != nip) && (*cp == 0))
1399 rootdev = MAKEBOOTDEV(major,
1400 (dev->d_kind.biosdisk.slice + 1) >> 4, /* XXX slices may be wrong here */
1401 (dev->d_kind.biosdisk.slice + 1) & 0xf,
1403 dev->d_kind.biosdisk.partition);
1404 DEBUG("dev is 0x%x\n", rootdev);