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);
128 * Max number of sectors to bounce-buffer if the request crosses a 64k boundary
130 #define BOUNCEBUF_SIZE 8192
131 #define BOUNCEBUF_SECTS (BOUNCEBUF_SIZE / BIOSDISK_SECSIZE)
133 struct devsw biosdisk = {
145 static int bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev);
146 static void bd_closedisk(struct open_disk *od);
147 static int bd_bestslice(struct open_disk *od);
148 static void bd_chainextended(struct open_disk *od, u_int32_t base,
151 static caddr_t bounce_base;
154 * Translate between BIOS device numbers and our private unit numbers.
157 bd_bios2unit(int biosdev)
161 DEBUG("looking for bios device 0x%x", biosdev);
162 for (i = 0; i < nbdinfo; i++) {
163 DEBUG("bd unit %d is BIOS device 0x%x", i, bdinfo[i].bd_unit);
164 if (bdinfo[i].bd_unit == biosdev)
171 bd_unit2bios(int unit)
173 if ((unit >= 0) && (unit < nbdinfo))
174 return(bdinfo[unit].bd_unit);
179 * Quiz the BIOS for disk devices, save a little info about them.
184 int base, unit, nfd = 0;
186 if (bounce_base == NULL)
187 bounce_base = malloc(BOUNCEBUF_SIZE * 2);
189 /* sequence 0, 0x80 */
190 for (base = 0; base <= 0x80; base += 0x80) {
191 for (unit = base; (nbdinfo < MAXBDDEV); unit++) {
192 /* check the BIOS equipment list for number of fixed disks */
194 (nfd >= *(unsigned char *)PTOV(BIOS_NUMDRIVES)))
197 bdinfo[nbdinfo].bd_unit = unit;
198 bdinfo[nbdinfo].bd_flags = (unit < 0x80) ? BD_FLOPPY : 0;
200 if (!bd_int13probe(&bdinfo[nbdinfo]))
203 /* XXX we need "disk aliases" to make this simpler */
204 printf("BIOS drive %c: is disk%d\n",
205 (unit < 0x80) ? ('A' + unit) : ('C' + unit - 0x80), nbdinfo);
215 * Try to detect a device supported by the legacy int13 BIOS
218 bd_int13probe(struct bdinfo *bd)
223 v86.edx = bd->bd_unit;
226 if (!(v86.efl & 0x1) && /* carry clear */
227 ((v86.edx & 0xff) > ((unsigned)bd->bd_unit & 0x7f))) { /* unit # OK */
230 * Ignore devices with an absurd sector size.
232 if ((v86.ecx & 0x3f) == 0) {
233 DEBUG("Invalid geometry for unit %d", bd->bd_unit);
236 bd->bd_flags |= BD_MODEINT13;
237 bd->bd_type = v86.ebx & 0xff;
239 /* Determine if we can use EDD with this device. */
241 v86.edx = bd->bd_unit;
244 if (!(v86.efl & 0x1) && /* carry clear */
245 ((v86.ebx & 0xffff) == 0xaa55) && /* signature */
246 (v86.ecx & 0x1)) { /* packets mode ok */
247 bd->bd_flags |= BD_MODEEDD1;
248 if((v86.eax & 0xff00) > 0x300)
249 bd->bd_flags |= BD_MODEEDD3;
257 * Print information about disks
260 bd_print(int verbose)
264 struct i386_devdesc dev;
265 struct open_disk *od;
266 struct dos_partition *dptr;
268 for (i = 0; i < nbdinfo; i++) {
269 sprintf(line, " disk%d: BIOS drive %c:\n", i,
270 (bdinfo[i].bd_unit < 0x80) ? ('A' + bdinfo[i].bd_unit) : ('C' + bdinfo[i].bd_unit - 0x80));
273 /* try to open the whole disk */
274 dev.d_kind.biosdisk.unit = i;
275 dev.d_kind.biosdisk.slice = -1;
276 dev.d_kind.biosdisk.partition = -1;
278 if (!bd_opendisk(&od, &dev)) {
280 /* Do we have a partition table? */
281 if (od->od_flags & BD_PARTTABOK) {
282 dptr = &od->od_slicetab[0];
284 /* Check for a "dedicated" disk */
285 if (((dptr[3].dp_typ == DOSPTYP_386BSD) ||
286 (dptr[3].dp_typ == DOSPTYP_NETBSD)) &&
287 (dptr[3].dp_start == 0) &&
288 (dptr[3].dp_size == 50000)) {
289 sprintf(line, " disk%d", i);
290 bd_printbsdslice(od, 0, line, verbose);
292 for (j = 0; j < od->od_nslices; j++) {
293 sprintf(line, " disk%ds%d", i, j + 1);
294 bd_printslice(od, &dptr[j], line, verbose);
304 * Print information about slices on a disk. For the size calculations we
305 * assume a 512 byte sector.
308 bd_printslice(struct open_disk *od, struct dos_partition *dp, char *prefix,
313 switch (dp->dp_typ) {
316 /* XXX: possibly add types 0 and 1, as in subr_disk, for gpt magic */
317 bd_printbsdslice(od, (daddr_t)dp->dp_start, prefix, verbose);
321 sprintf(line, "%s: Linux swap %.6dMB (%d - %d)\n",
322 prefix, dp->dp_size / 2048,
323 dp->dp_start, dp->dp_start + dp->dp_size);
325 sprintf(line, "%s: Linux swap\n", prefix);
330 * read the superblock to confirm this is an ext2fs partition?
333 sprintf(line, "%s: ext2fs %.6dMB (%d - %d)\n", prefix,
334 dp->dp_size / 2048, dp->dp_start,
335 dp->dp_start + dp->dp_size);
337 sprintf(line, "%s: ext2fs\n", prefix);
339 case 0x00: /* unused partition */
344 sprintf(line, "%s: FAT-12 %.6dMB (%d - %d)\n", prefix,
345 dp->dp_size / 2048, dp->dp_start,
346 dp->dp_start + dp->dp_size);
348 sprintf(line, "%s: FAT-12\n", prefix);
354 sprintf(line, "%s: FAT-16 %.6dMB (%d - %d)\n", prefix,
355 dp->dp_size / 2048, dp->dp_start,
356 dp->dp_start + dp->dp_size);
358 sprintf(line, "%s: FAT-16\n", prefix);
363 sprintf(line, "%s: FAT-32 %.6dMB (%d - %d)\n", prefix,
364 dp->dp_size / 2048, dp->dp_start,
365 dp->dp_start + dp->dp_size);
367 sprintf(line, "%s: FAT-32\n", prefix);
371 sprintf(line, "%s: Unknown fs: 0x%x %.6dMB (%d - %d)\n",
372 prefix, dp->dp_typ, dp->dp_size / 2048,
373 dp->dp_start, dp->dp_start + dp->dp_size);
375 sprintf(line, "%s: Unknown fs: 0x%x\n", prefix,
382 print_partition(u_int8_t fstype, unsigned long long offset,
383 unsigned long long size, int i, int od_flags,
384 char *prefix, int verbose, int type)
389 * For each partition, make sure we know what type of fs it is. If
390 * not, then skip it. However, since floppies often have bogus
391 * fstypes, print the 'a' partition on a floppy even if it is marked
394 if ((fstype == FS_SWAP) ||
395 (fstype == FS_VINUM) ||
396 (fstype == FS_HAMMER) ||
397 (fstype == FS_HAMMER2) ||
398 (fstype == FS_BSDFFS) ||
399 (fstype == FS_ZFS) ||
400 (fstype == FS_JFS2) ||
401 ((fstype == FS_UNUSED) &&
402 (od_flags & BD_FLOPPY) && (i == 0))) {
404 /* Only print out statistics in verbose mode */
406 sprintf(line, "%c %s%c: %s %.6lluMB (%llu - %llu)\n",
407 /* prefix disks that can be used to load modules with '*' */
408 ((fstype == FS_BSDFFS) || (fstype == FS_UNUSED) ||
409 (fstype == FS_VINUM)) ? '*' : ' ',
411 (fstype == FS_SWAP) ? "swap" :
412 (fstype == FS_VINUM) ? "vinum" :
413 (fstype == FS_HAMMER) ? "HAMMER" :
414 (fstype == FS_HAMMER2) ? "HAMMER2" :
415 (fstype == FS_JFS2) ? "JFS2" :
416 (fstype == FS_ZFS) ? "ZFS" :
417 (fstype == FS_BSDFFS) ? "FFS" :
419 (type==32)?(size / 2048):(size/1024/1024),
423 sprintf(line, "%c %s%c: %s\n",
424 /* prefix disks that can be used to load modules with '*' */
425 ((fstype == FS_BSDFFS) || (fstype == FS_UNUSED) ||
426 (fstype == FS_VINUM)) ? '*' : ' ',
428 (fstype == FS_SWAP) ? "swap" :
429 (fstype == FS_VINUM) ? "vinum" :
430 (fstype == FS_HAMMER) ? "HAMMER" :
431 (fstype == FS_HAMMER2) ? "HAMMER2" :
432 (fstype == FS_JFS2) ? "JFS2" :
433 (fstype == FS_ZFS) ? "ZFS" :
434 (fstype == FS_BSDFFS) ? "FFS" :
443 * Print out each valid partition in the disklabel of a FreeBSD slice.
444 * For size calculations, we assume a 512 byte sector size.
447 bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix,
451 char buf[BIOSDISK_SECSIZE*2];
452 struct disklabel32 *lp = NULL;
453 struct disklabel64 *lp64 = NULL;
457 if (bd_read(od, offset + LABELSECTOR32, 1, buf))
459 lp =(struct disklabel32 *)(&buf[0]);
460 if (lp->d_magic != DISKMAGIC32) {
461 if (bd_read(od, offset, 2, buf))
464 lp64 =(struct disklabel64 *)(&buf[0]);
465 if (lp64->d_magic != DISKMAGIC64) {
466 sprintf(line, "%s: bad disklabel\n", prefix);
470 lp = NULL; /* PARANOID */
473 /* We got ourselves a disklabel64 here */
474 for (i = 0; i < lp64->d_npartitions; i++) {
475 if (lp64->d_partitions[i].p_bsize == 0)
478 print_partition(lp64->d_partitions[i].p_fstype,
479 lp64->d_partitions[i].p_boffset,
480 lp64->d_partitions[i].p_bsize,
481 i, od->od_flags, prefix, verbose, 64);
484 /* Print partitions */
485 for (i = 0; i < lp->d_npartitions; i++) {
486 print_partition(lp->d_partitions[i].p_fstype,
487 lp->d_partitions[i].p_offset,
488 lp->d_partitions[i].p_size,
489 i, od->od_flags, prefix, verbose, 32);
496 * Attempt to open the disk described by (dev) for use by (f).
498 * Note that the philosophy here is "give them exactly what
499 * they ask for". This is necessary because being too "smart"
500 * about what the user might want leads to complications.
501 * (eg. given no slice or partition value, with a disk that is
502 * sliced - are they after the first BSD slice, or the DOS
506 bd_open(struct open_file *f, ...)
509 struct i386_devdesc *dev;
510 struct open_disk *od;
514 dev = va_arg(ap, struct i386_devdesc *);
516 if ((error = bd_opendisk(&od, dev)))
522 ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od;
523 DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff);
528 bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev)
530 struct dos_partition *dptr;
531 struct disklabel32 *lp;
532 struct disklabel64 *lp64;
533 struct open_disk *od;
534 int sector, slice, i;
536 static char buf[BUFSIZE];
538 if (dev->d_kind.biosdisk.unit >= nbdinfo) {
539 DEBUG("attempt to open nonexistent disk");
543 od = (struct open_disk *)malloc(sizeof(struct open_disk));
549 /* Look up BIOS unit number, intialise open_disk structure */
550 od->od_dkunit = dev->d_kind.biosdisk.unit;
551 od->od_unit = bdinfo[od->od_dkunit].bd_unit;
552 od->od_flags = bdinfo[od->od_dkunit].bd_flags;
556 DEBUG("open '%s', unit 0x%x slice %d partition %c",
557 i386_fmtdev(dev), dev->d_kind.biosdisk.unit,
558 dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition + 'a');
560 /* Get geometry for this open (removable device may have changed) */
561 if (bd_getgeom(od)) {
562 DEBUG("can't get geometry");
568 * Following calculations attempt to determine the correct value
569 * for d->od_boff by looking for the slice and partition specified,
570 * or searching for reasonable defaults.
574 * Find the slice in the DOS slice table.
576 if (bd_read(od, 0, 1, buf)) {
577 DEBUG("error reading MBR");
583 * Check the slice table magic.
585 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
586 /* If a slice number was explicitly supplied, this is an error */
587 if (dev->d_kind.biosdisk.slice > 0) {
588 DEBUG("no slice table/MBR (no magic)");
593 goto unsliced; /* may be a floppy */
597 * copy the partition table, then pick up any extended partitions. The
598 * base partition table always has four entries, even if some of them
599 * represented extended partitions. However, any additional sub-extended
600 * partitions will be silently recursed and not included in the slice
603 bcopy(buf + DOSPARTOFF, &od->od_slicetab,
604 sizeof(struct dos_partition) * NDOSPART);
605 od->od_nslices = NDOSPART;
607 dptr = &od->od_slicetab[0];
608 for (i = 0; i < NDOSPART; i++, dptr++) {
609 if ((dptr->dp_typ == DOSPTYP_EXT) || (dptr->dp_typ == DOSPTYP_EXTLBA))
610 bd_chainextended(od, dptr->dp_start, 0); /* 1st offset is zero */
612 od->od_flags |= BD_PARTTABOK;
613 dptr = &od->od_slicetab[0];
616 * Overflow entries are not loaded into memory but we still keep
617 * track of the count. Fix it up now.
619 if (od->od_nslices > NEXTDOSPART)
620 od->od_nslices = NEXTDOSPART;
623 * Is this a request for the whole disk?
625 if (dev->d_kind.biosdisk.slice == -1) {
631 * if a slice number was supplied but not found, this is an error.
633 if (dev->d_kind.biosdisk.slice > 0) {
634 slice = dev->d_kind.biosdisk.slice - 1;
635 if (slice >= od->od_nslices) {
636 DEBUG("slice %d not found", slice);
643 * Check for the historically bogus MBR found on true dedicated disks
645 if ((dptr[3].dp_typ == DOSPTYP_386BSD) &&
646 (dptr[3].dp_start == 0) &&
647 (dptr[3].dp_size == 50000)) {
652 /* Try to auto-detect the best slice; this should always give a slice number */
653 if (dev->d_kind.biosdisk.slice == 0) {
654 slice = bd_bestslice(od);
659 dev->d_kind.biosdisk.slice = slice;
662 dptr = &od->od_slicetab[0];
664 * Accept the supplied slice number unequivocally (we may be looking
665 * at a DOS partition).
667 dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */
668 sector = dptr->dp_start;
669 DEBUG("slice entry %d at %d, %d sectors", dev->d_kind.biosdisk.slice - 1, sector, dptr->dp_size);
672 * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition
674 if ((dptr->dp_typ == DOSPTYP_386BSD) && (dev->d_kind.biosdisk.partition < 0))
675 dev->d_kind.biosdisk.partition = 0;
679 * Now we have the slice offset, look for the partition in the disklabel if we have
680 * a partition to start with.
682 * XXX we might want to check the label checksum.
684 if (dev->d_kind.biosdisk.partition < 0) {
685 od->od_boff = sector; /* no partition, must be after the slice */
686 DEBUG("opening raw slice");
689 if (bd_read(od, sector + LABELSECTOR32, 1, buf)) {
690 DEBUG("error reading disklabel");
694 DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel32), buf + LABELOFFSET32, &od->od_disklabel);
695 bcopy(buf + LABELOFFSET32, &od->od_disklabel, sizeof(struct disklabel32));
696 lp = &od->od_disklabel;
698 if (lp->d_magic == DISKMAGIC32) {
699 od->od_flags |= BD_LABELOK;
701 if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) {
702 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
703 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions);
710 /* Complain if the partition is unused unless this is a floppy. */
711 if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) &&
712 !(od->od_flags & BD_FLOPPY))
713 DEBUG("warning, partition marked as unused");
717 lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset -
718 lp->d_partitions[RAW_PART].p_offset +
724 /* else maybe DISKLABEL64? */
726 if (bd_read(od, sector, (sizeof(od->od_disklabel64) + 511) / 512, buf)) {
727 DEBUG("error reading disklabel");
731 DEBUG("copy %d bytes of label from %p to %p", sizeof(od->od_disklabel64), buf, &od->od_disklabel64);
732 bcopy(buf, &od->od_disklabel64, sizeof(od->od_disklabel64));
733 lp64 = &od->od_disklabel64;
735 if (lp64->d_magic == DISKMAGIC64) {
736 od->od_flags |= BD_LABELOK;
738 if (dev->d_kind.biosdisk.partition >= lp64->d_npartitions ||
739 lp64->d_partitions[dev->d_kind.biosdisk.partition].p_bsize == 0) {
740 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
741 'a' + dev->d_kind.biosdisk.partition, 'a' + lp64->d_npartitions);
748 lp64->d_partitions[dev->d_kind.biosdisk.partition].p_boffset / 512 +
751 DEBUG("disklabel64 slice at %d", od->od_boff);
754 DEBUG("no disklabel");
763 *odp = od; /* return the open disk */
770 bd_chainextended(struct open_disk *od, u_int32_t base, u_int32_t offset)
772 char buf[BIOSDISK_SECSIZE];
773 struct dos_partition *dp1, *dp2;
776 if (bd_read(od, (daddr_t)(base + offset), 1, buf)) {
777 printf("\nerror reading extended partition table");
782 * dp1 points to the first record in the on-disk XPT,
783 * dp2 points to the next entry in the in-memory parition table.
785 * NOTE: dp2 may be out of bounds if od_nslices >= NEXTDOSPART.
787 * NOTE: unlike the extended partitions in our primary dos partition
788 * table, we do not record recursed extended partitions themselves
789 * in our in-memory partition table.
791 * NOTE: recording within our in-memory table must be breadth first
792 * ot match what the kernel does. Thus, two passes are required.
794 * NOTE: partitioning programs which support extended partitions seem
795 * to always use the first entry for the user partition and the
796 * second entry to chain, and also appear to disallow more then one
797 * extended partition at each level. Nevertheless we make our code
798 * somewhat more generic (and the same as the kernel's own slice
801 dp1 = (struct dos_partition *)(&buf[DOSPARTOFF]);
802 dp2 = &od->od_slicetab[od->od_nslices];
804 for (i = 0; i < NDOSPART; ++i, ++dp1) {
805 if (dp1->dp_scyl == 0 && dp1->dp_shd == 0 &&
806 dp1->dp_ssect == 0 && dp1->dp_start == 0 &&
810 if ((dp1->dp_typ == DOSPTYP_EXT) ||
811 (dp1->dp_typ == DOSPTYP_EXTLBA)) {
813 * breadth first traversal, must skip in the
820 * Only load up the in-memory data if we haven't overflowed
821 * our in-memory array.
823 if (od->od_nslices < NEXTDOSPART) {
824 dp2->dp_typ = dp1->dp_typ;
825 dp2->dp_start = base + offset + dp1->dp_start;
826 dp2->dp_size = dp1->dp_size;
833 * Pass 2 - handle extended partitions. Note that the extended
834 * slice itself is not stored in the slice array when we recurse,
835 * but any 'original' top-level extended slices are. This is to
836 * match what the kernel does.
839 for (i = 0; i < NDOSPART; ++i, ++dp1) {
840 if (dp1->dp_scyl == 0 && dp1->dp_shd == 0 &&
841 dp1->dp_ssect == 0 && dp1->dp_start == 0 &&
845 if ((dp1->dp_typ == DOSPTYP_EXT) ||
846 (dp1->dp_typ == DOSPTYP_EXTLBA))
847 bd_chainextended(od, base, dp1->dp_start);
852 * Search for a slice with the following preferences:
854 * 1: Active FreeBSD slice
855 * 2: Non-active FreeBSD slice
856 * 3: Active Linux slice
857 * 4: non-active Linux slice
858 * 5: Active FAT/FAT32 slice
859 * 6: non-active FAT/FAT32 slice
861 #define PREF_RAWDISK 0
862 #define PREF_FBSD_ACT 1
864 #define PREF_LINUX_ACT 3
866 #define PREF_DOS_ACT 5
871 * slicelimit is in the range 0 .. NDOSPART
874 bd_bestslice(struct open_disk *od)
876 struct dos_partition *dp;
881 preflevel = PREF_NONE;
883 dp = &od->od_slicetab[0];
884 for (i = 0; i < od->od_nslices; i++, dp++) {
885 switch (dp->dp_typ) {
886 case DOSPTYP_386BSD: /* FreeBSD */
887 pref = dp->dp_flag & 0x80 ? PREF_FBSD_ACT : PREF_FBSD;
891 pref = dp->dp_flag & 0x80 ? PREF_LINUX_ACT : PREF_LINUX;
894 case 0x01: /* DOS/Windows */
900 pref = dp->dp_flag & 0x80 ? PREF_DOS_ACT : PREF_DOS;
906 if (pref < preflevel) {
915 bd_close(struct open_file *f)
917 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data);
924 bd_closedisk(struct open_disk *od)
926 DEBUG("open_disk %p", od);
928 /* XXX is this required? (especially if disk already open...) */
929 if (od->od_flags & BD_FLOPPY)
936 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
938 struct bcache_devdata bcd;
939 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
941 bcd.dv_strategy = bd_realstrategy;
942 bcd.dv_devdata = devdata;
943 return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize));
947 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
949 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
951 #ifdef BD_SUPPORT_FRAGS
952 char fragbuf[BIOSDISK_SECSIZE];
955 fragsize = size % BIOSDISK_SECSIZE;
957 if (size % BIOSDISK_SECSIZE)
958 panic("bd_strategy: %d bytes I/O not multiple of block size", size);
961 DEBUG("open_disk %p", od);
965 blks = size / BIOSDISK_SECSIZE;
966 DEBUG("read %d from %d to %p", blks, dblk, buf);
970 if (blks && bd_read(od, dblk, blks, buf)) {
974 #ifdef BD_SUPPORT_FRAGS
975 DEBUG("bd_strategy: frag read %d from %d+%d to %p",
976 fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE));
977 if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) {
978 DEBUG("frag read error");
981 bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize);
987 blks = size / BIOSDISK_SECSIZE;
988 DEBUG("write %d from %d to %p", blks, dblk, buf);
992 if (blks && bd_write(od, dblk, blks, buf)) {
993 DEBUG("write error");
996 #ifdef BD_SUPPORT_FRAGS
998 DEBUG("Attempted to write a frag");
1006 break; /* DO NOTHING */
1012 bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1014 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer;
1015 caddr_t p, xp, bbuf, breg;
1017 /* Just in case some idiot actually tries to read -1 blocks... */
1021 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1026 * Always bounce. Our buffer is probably not segment-addressable.
1031 * There is a 64k physical boundary somewhere in the destination
1032 * buffer, so we have to arrange a suitable bounce buffer. Allocate
1033 * a buffer twice as large as we need to. Use the bottom half unless
1034 * there is a break there, in which case we use the top half.
1037 x = min(BOUNCEBUF_SECTS, (unsigned)blks);
1039 if (((u_int32_t)VTOP(bbuf) & 0xffff8000) ==
1040 ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE - 1) & 0xffff8000)) {
1043 breg = bbuf + x * BIOSDISK_SECSIZE;
1045 maxfer = x; /* limit transfers to bounce region size */
1053 cyl = x / bpc; /* block # / blocks per cylinder */
1054 x %= bpc; /* block offset into cylinder */
1055 hd = x / od->od_sec; /* offset / blocks per track */
1056 sec = x % od->od_sec; /* offset into track */
1058 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */
1059 x = szmin(od->od_sec - sec, resid);
1061 x = min(x, maxfer); /* fit bounce buffer */
1063 /* where do we transfer to? */
1064 xp = (bbuf == NULL ? p : breg);
1066 /* correct sector number for 1-based BIOS numbering */
1070 * Loop retrying the operation a couple of times. The BIOS may also
1073 for (retry = 0; retry < 3; retry++) {
1075 * If retrying, reset the drive.
1078 v86.ctl = V86_FLAGS;
1081 v86.edx = od->od_unit;
1086 * Always use EDD if the disk supports it, otherwise fall back
1087 * to CHS mode (returning an error if the cylinder number is
1090 if (od->od_flags & BD_MODEEDD1) {
1091 static unsigned short packet[8];
1095 packet[2] = VTOPOFF(xp);
1096 packet[3] = VTOPSEG(xp);
1097 packet[4] = dblk & 0xffff;
1098 packet[5] = dblk >> 16;
1101 v86.ctl = V86_FLAGS;
1104 v86.edx = od->od_unit;
1105 v86.ds = VTOPSEG(packet);
1106 v86.esi = VTOPOFF(packet);
1108 result = (v86.efl & 0x1);
1111 } else if (cyl < 1024) {
1112 /* Use normal CHS addressing */
1113 v86.ctl = V86_FLAGS;
1115 v86.eax = 0x200 | x;
1116 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1117 v86.edx = (hd << 8) | od->od_unit;
1118 v86.es = VTOPSEG(xp);
1119 v86.ebx = VTOPOFF(xp);
1121 result = (v86.efl & 0x1);
1130 DEBUG("%u sectors from %u/%u/%d to %p (0x%x) %s",
1131 x, cyl, hd, sec - 1, p, VTOP(p), result ? "failed" : "ok");
1132 /* BUG here, cannot use v86 in printf because putchar uses it too */
1133 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x",
1135 ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec,
1136 (hd << 8) | od->od_unit,
1137 (v86.eax >> 8) & 0xff);
1141 bcopy(breg, p, x * BIOSDISK_SECSIZE);
1142 p += (x * BIOSDISK_SECSIZE);
1147 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1153 bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1155 u_int x, bpc, cyl, hd, sec, result, resid, retry, maxfer;
1156 caddr_t p, xp, bbuf, breg;
1158 /* Just in case some idiot actually tries to read -1 blocks... */
1162 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1167 * Always bounce. Our buffer is probably not segment-addressable.
1171 * There is a 64k physical boundary somewhere in the destination
1172 * buffer, so we have to arrange a suitable bounce buffer. Allocate
1173 * a buffer twice as large as we need to. Use the bottom half
1174 * unless there is a break there, in which case we use the top half.
1177 x = min(BOUNCEBUF_SECTS, (unsigned)blks);
1179 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) ==
1180 ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE - 1) & 0xffff0000)) {
1183 breg = bbuf + x * BIOSDISK_SECSIZE;
1185 maxfer = x; /* limit transfers to bounce region size */
1193 cyl = x / bpc; /* block # / blocks per cylinder */
1194 x %= bpc; /* block offset into cylinder */
1195 hd = x / od->od_sec; /* offset / blocks per track */
1196 sec = x % od->od_sec; /* offset into track */
1198 /* play it safe and don't cross track boundaries (XXX this is probably unnecessary) */
1199 x = szmin(od->od_sec - sec, resid);
1201 x = szmin(x, maxfer); /* fit bounce buffer */
1203 /* where do we transfer to? */
1204 xp = (bbuf == NULL ? p : breg);
1206 /* correct sector number for 1-based BIOS numbering */
1210 /* Put your Data In, Put your Data out,
1211 Put your Data In, and shake it all about
1214 bcopy(p, breg, x * BIOSDISK_SECSIZE);
1215 p += (x * BIOSDISK_SECSIZE);
1220 * Loop retrying the operation a couple of times. The BIOS may also
1223 for (retry = 0; retry < 3; retry++) {
1225 * If retrying, reset the drive.
1228 v86.ctl = V86_FLAGS;
1231 v86.edx = od->od_unit;
1236 * Always use EDD if the disk supports it, otherwise fall back
1237 * to CHS mode (returning an error if the cylinder number is
1240 if (od->od_flags & BD_MODEEDD1) {
1241 static unsigned short packet[8];
1245 packet[2] = VTOPOFF(xp);
1246 packet[3] = VTOPSEG(xp);
1247 packet[4] = dblk & 0xffff;
1248 packet[5] = dblk >> 16;
1251 v86.ctl = V86_FLAGS;
1253 /* Should we Write with verify ?? 0x4302 ? */
1255 v86.edx = od->od_unit;
1256 v86.ds = VTOPSEG(packet);
1257 v86.esi = VTOPOFF(packet);
1259 result = (v86.efl & 0x1);
1262 } else if (cyl < 1024) {
1263 /* Use normal CHS addressing */
1264 v86.ctl = V86_FLAGS;
1266 v86.eax = 0x300 | x;
1267 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1268 v86.edx = (hd << 8) | od->od_unit;
1269 v86.es = VTOPSEG(xp);
1270 v86.ebx = VTOPOFF(xp);
1272 result = (v86.efl & 0x1);
1281 DEBUG("%u sectors from %u/%u/%d to %p (0x%x) %s", x, cyl, hd, sec - 1, p, VTOP(p), result ? "failed" : "ok");
1282 /* BUG here, cannot use v86 in printf because putchar uses it too */
1283 DEBUG("ax = 0x%04x cx = 0x%04x dx = 0x%04x status 0x%x",
1284 0x200 | x, ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec, (hd << 8) | od->od_unit, (v86.eax >> 8) & 0xff);
1289 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1293 bd_getgeom(struct open_disk *od)
1296 v86.ctl = V86_FLAGS;
1299 v86.edx = od->od_unit;
1302 if ((v86.efl & 0x1) || /* carry set */
1303 ((v86.edx & 0xff) <= (unsigned)(od->od_unit & 0x7f))) /* unit # bad */
1306 /* convert max cyl # -> # of cylinders */
1307 od->od_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1;
1308 /* convert max head # -> # of heads */
1309 od->od_hds = ((v86.edx & 0xff00) >> 8) + 1;
1310 od->od_sec = v86.ecx & 0x3f;
1312 DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec);
1317 * Return the BIOS geometry of a given "fixed drive" in a format
1318 * suitable for the legacy bootinfo structure. Since the kernel is
1319 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we
1320 * prefer to get the information directly, rather than rely on being
1321 * able to put it together from information already maintained for
1322 * different purposes and for a probably different number of drives.
1324 * For valid drives, the geometry is expected in the format (31..0)
1325 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are
1326 * indicated by returning the geometry of a "1.2M" PC-format floppy
1327 * disk. And, incidentally, what is returned is not the geometry as
1328 * such but the highest valid cylinder, head, and sector numbers.
1331 bd_getbigeom(int bunit)
1334 v86.ctl = V86_FLAGS;
1337 v86.edx = 0x80 + bunit;
1341 return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
1342 (v86.edx & 0xff00) | (v86.ecx & 0x3f);
1346 * Return a suitable cdev_t value for (dev).
1348 * In the case where it looks like (dev) is a SCSI disk, we allow the number of
1349 * IDE disks to be specified in $num_ide_disks. There should be a Better Way.
1352 bd_getdev(struct i386_devdesc *dev)
1354 struct open_disk *od;
1359 int unitofs = 0, i, unit;
1361 biosdev = bd_unit2bios(dev->d_kind.biosdisk.unit);
1362 DEBUG("unit %d BIOS device %d", dev->d_kind.biosdisk.unit, biosdev);
1363 if (biosdev == -1) /* not a BIOS device */
1365 if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */
1368 if (biosdev < 0x80) {
1369 /* floppy (or emulated floppy) or ATAPI device */
1370 if (bdinfo[dev->d_kind.biosdisk.unit].bd_type == DT_ATAPI) {
1371 /* is an ATAPI disk */
1374 /* is a floppy disk */
1379 if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) {
1380 /* label OK, disk labelled as SCSI */
1382 /* check for unit number correction hint, now deprecated */
1383 if ((nip = getenv("num_ide_disks")) != NULL) {
1384 i = strtol(nip, &cp, 0);
1385 /* check for parse error */
1386 if ((cp != nip) && (*cp == 0))
1390 /* assume an IDE disk */
1394 /* default root disk unit number */
1395 unit = (biosdev & 0x7f) - unitofs;
1397 /* XXX a better kludge to set the root disk unit number */
1398 if ((nip = getenv("root_disk_unit")) != NULL) {
1399 i = strtol(nip, &cp, 0);
1400 /* check for parse error */
1401 if ((cp != nip) && (*cp == 0))
1405 rootdev = MAKEBOOTDEV(major,
1406 (dev->d_kind.biosdisk.slice + 1) >> 4, /* XXX slices may be wrong here */
1407 (dev->d_kind.biosdisk.slice + 1) & 0xf,
1409 dev->d_kind.biosdisk.partition);
1410 DEBUG("dev is 0x%x\n", rootdev);