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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
31 * BIOS disk device handling.
33 * Ideas and algorithms from:
35 * - NetBSD libi386/biosdisk.c
36 * - FreeBSD biosboot/disk.c
42 #include <sys/disklabel.h>
43 #include <sys/diskmbr.h>
45 #include <machine/bootinfo.h>
50 #include <bootstrap.h>
54 #define BIOS_NUMDRIVES 0x475
55 #define BIOSDISK_SECSIZE 512
56 #define BUFSIZE (1 * BIOSDISK_SECSIZE)
57 #define MAXBDDEV MAXDEV
59 #define DT_ATAPI 0x10 /* disk type for ATAPI floppies */
60 #define WDMAJOR 0 /* major numbers for devices we frontend for */
66 # define DEBUG(fmt, args...) printf("%s: " fmt "\n" , __func__ , ## args)
68 # define DEBUG(fmt, args...)
71 #ifdef LOADER_GPT_SUPPORT
81 int od_dkunit; /* disk unit number */
82 int od_unit; /* BIOS unit number */
83 int od_cyl; /* BIOS geometry */
86 int od_boff; /* block offset from beginning of BIOS disk */
88 #define BD_MODEINT13 0x0000
89 #define BD_MODEEDD1 0x0001
90 #define BD_MODEEDD3 0x0002
91 #define BD_MODEMASK 0x0003
92 #define BD_FLOPPY 0x0004
93 #define BD_LABELOK 0x0008
94 #define BD_PARTTABOK 0x0010
95 #ifdef LOADER_GPT_SUPPORT
96 #define BD_GPTOK 0x0020
100 struct disklabel mbr_disklabel;
101 int mbr_nslices; /* slice count */
102 struct dos_partition mbr_slicetab[NEXTDOSPART];
104 #ifdef LOADER_GPT_SUPPORT
107 struct gpt_part *gpt_partitions;
113 #define od_disklabel _data._mbr.mbr_disklabel
114 #define od_nslices _data._mbr.mbr_nslices
115 #define od_slicetab _data._mbr.mbr_slicetab
116 #ifdef LOADER_GPT_SUPPORT
117 #define od_nparts _data._gpt.gpt_nparts
118 #define od_partitions _data._gpt.gpt_partitions
122 * List of BIOS devices, translation from disk unit number to
127 int bd_unit; /* BIOS unit number */
129 int bd_type; /* BIOS 'drive type' (floppy only) */
131 static int nbdinfo = 0;
133 static int bd_getgeom(struct open_disk *od);
134 static int bd_read(struct open_disk *od, daddr_t dblk, int blks,
136 static int bd_write(struct open_disk *od, daddr_t dblk, int blks,
139 static int bd_int13probe(struct bdinfo *bd);
141 #ifdef LOADER_GPT_SUPPORT
142 static void bd_printgptpart(struct open_disk *od, struct gpt_part *gp,
143 char *prefix, int verbose);
145 static void bd_printslice(struct open_disk *od, struct dos_partition *dp,
146 char *prefix, int verbose);
147 static void bd_printbsdslice(struct open_disk *od, daddr_t offset,
148 char *prefix, int verbose);
150 static int bd_init(void);
151 static int bd_strategy(void *devdata, int flag, daddr_t dblk,
152 size_t size, char *buf, size_t *rsize);
153 static int bd_realstrategy(void *devdata, int flag, daddr_t dblk,
154 size_t size, char *buf, size_t *rsize);
155 static int bd_open(struct open_file *f, ...);
156 static int bd_close(struct open_file *f);
157 static void bd_print(int verbose);
159 struct devsw biosdisk = {
171 static int bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev);
172 static void bd_closedisk(struct open_disk *od);
173 static int bd_open_mbr(struct open_disk *od, struct i386_devdesc *dev);
174 static int bd_bestslice(struct open_disk *od);
175 static void bd_checkextended(struct open_disk *od, int slicenum);
176 #ifdef LOADER_GPT_SUPPORT
177 static int bd_open_gpt(struct open_disk *od, struct i386_devdesc *dev);
178 static struct gpt_part *bd_best_gptpart(struct open_disk *od);
182 * Translate between BIOS device numbers and our private unit numbers.
185 bd_bios2unit(int biosdev)
189 DEBUG("looking for bios device 0x%x", biosdev);
190 for (i = 0; i < nbdinfo; i++) {
191 DEBUG("bd unit %d is BIOS device 0x%x", i, bdinfo[i].bd_unit);
192 if (bdinfo[i].bd_unit == biosdev)
199 bd_unit2bios(int unit)
201 if ((unit >= 0) && (unit < nbdinfo))
202 return(bdinfo[unit].bd_unit);
207 * Quiz the BIOS for disk devices, save a little info about them.
212 int base, unit, nfd = 0;
214 /* sequence 0, 0x80 */
215 for (base = 0; base <= 0x80; base += 0x80) {
216 for (unit = base; (nbdinfo < MAXBDDEV); unit++) {
217 /* check the BIOS equipment list for number of fixed disks */
219 (nfd >= *(unsigned char *)PTOV(BIOS_NUMDRIVES)))
222 bdinfo[nbdinfo].bd_unit = unit;
223 bdinfo[nbdinfo].bd_flags = (unit < 0x80) ? BD_FLOPPY : 0;
225 if (!bd_int13probe(&bdinfo[nbdinfo]))
228 /* XXX we need "disk aliases" to make this simpler */
229 printf("BIOS drive %c: is disk%d\n",
230 (unit < 0x80) ? ('A' + unit) : ('C' + unit - 0x80), nbdinfo);
240 * Try to detect a device supported by the legacy int13 BIOS
243 bd_int13probe(struct bdinfo *bd)
248 v86.edx = bd->bd_unit;
251 if (!(v86.efl & 0x1) && /* carry clear */
252 ((v86.edx & 0xff) > ((unsigned)bd->bd_unit & 0x7f))) { /* unit # OK */
253 if ((v86.ecx & 0x3f) == 0) { /* absurd sector size */
254 DEBUG("Invalid geometry for unit %d", bd->bd_unit);
255 return(0); /* skip device */
257 bd->bd_flags |= BD_MODEINT13;
258 bd->bd_type = v86.ebx & 0xff;
260 /* Determine if we can use EDD with this device. */
262 v86.edx = bd->bd_unit;
265 if (!(v86.efl & 0x1) && /* carry clear */
266 ((v86.ebx & 0xffff) == 0xaa55) && /* signature */
267 (v86.ecx & 0x1)) { /* packets mode ok */
268 bd->bd_flags |= BD_MODEEDD1;
269 if((v86.eax & 0xff00) >= 0x3000)
270 bd->bd_flags |= BD_MODEEDD3;
278 * Print information about disks
281 bd_print(int verbose)
285 struct i386_devdesc dev;
286 struct open_disk *od;
287 struct dos_partition *dptr;
289 for (i = 0; i < nbdinfo; i++) {
290 sprintf(line, " disk%d: BIOS drive %c:\n", i,
291 (bdinfo[i].bd_unit < 0x80) ? ('A' + bdinfo[i].bd_unit) : ('C' + bdinfo[i].bd_unit - 0x80));
294 /* try to open the whole disk */
296 dev.d_kind.biosdisk.slice = -1;
297 dev.d_kind.biosdisk.partition = -1;
299 if (!bd_opendisk(&od, &dev)) {
301 #ifdef LOADER_GPT_SUPPORT
302 /* Do we have a GPT table? */
303 if (od->od_flags & BD_GPTOK) {
304 for (j = 0; j < od->od_nparts; j++) {
305 sprintf(line, " disk%dp%d", i,
306 od->od_partitions[j].gp_index);
307 bd_printgptpart(od, &od->od_partitions[j], line, verbose);
311 /* Do we have a partition table? */
312 if (od->od_flags & BD_PARTTABOK) {
313 dptr = &od->od_slicetab[0];
315 /* Check for a "dedicated" disk */
316 if ((dptr[3].dp_typ == DOSPTYP_386BSD) &&
317 (dptr[3].dp_start == 0) &&
318 (dptr[3].dp_size == 50000)) {
319 sprintf(line, " disk%d", i);
320 bd_printbsdslice(od, 0, line, verbose);
322 for (j = 0; j < od->od_nslices; j++) {
323 sprintf(line, " disk%ds%d", i, j + 1);
324 bd_printslice(od, &dptr[j], line, verbose);
333 #ifdef LOADER_GPT_SUPPORT
334 static uuid_t efi = GPT_ENT_TYPE_EFI;
335 static uuid_t freebsd_boot = GPT_ENT_TYPE_FREEBSD_BOOT;
336 static uuid_t freebsd_ufs = GPT_ENT_TYPE_FREEBSD_UFS;
337 static uuid_t freebsd_swap = GPT_ENT_TYPE_FREEBSD_SWAP;
338 static uuid_t freebsd_zfs = GPT_ENT_TYPE_FREEBSD_ZFS;
339 static uuid_t ms_basic_data = GPT_ENT_TYPE_MS_BASIC_DATA;
342 bd_printgptpart(struct open_disk *od, struct gpt_part *gp, char *prefix,
351 size = (gp->gp_end + 1 - gp->gp_start) / 2048;
353 if (size >= 10240000) {
356 } else if (size >= 10000) {
360 sprintf(stats, " %.6ld%cB", (long)size, unit);
364 if (uuid_equal(&gp->gp_type, &efi, NULL))
365 sprintf(line, "%s: EFI%s\n", prefix, stats);
366 else if (uuid_equal(&gp->gp_type, &ms_basic_data, NULL))
367 sprintf(line, "%s: FAT/NTFS%s\n", prefix, stats);
368 else if (uuid_equal(&gp->gp_type, &freebsd_boot, NULL))
369 sprintf(line, "%s: FreeBSD boot%s\n", prefix, stats);
370 else if (uuid_equal(&gp->gp_type, &freebsd_ufs, NULL))
371 sprintf(line, "%s: FreeBSD UFS%s\n", prefix, stats);
372 else if (uuid_equal(&gp->gp_type, &freebsd_zfs, NULL))
373 sprintf(line, "%s: FreeBSD ZFS%s\n", prefix, stats);
374 else if (uuid_equal(&gp->gp_type, &freebsd_swap, NULL))
375 sprintf(line, "%s: FreeBSD swap%s\n", prefix, stats);
377 sprintf(line, "%s: %08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x%s\n",
378 gp->gp_type.time_low, gp->gp_type.time_mid,
379 gp->gp_type.time_hi_and_version,
380 gp->gp_type.clock_seq_hi_and_reserved, gp->gp_type.clock_seq_low,
381 gp->gp_type.node[0], gp->gp_type.node[1], gp->gp_type.node[2],
382 gp->gp_type.node[3], gp->gp_type.node[4], gp->gp_type.node[5],
389 * Print information about slices on a disk. For the size calculations we
390 * assume a 512 byte sector.
393 bd_printslice(struct open_disk *od, struct dos_partition *dp, char *prefix,
398 switch (dp->dp_typ) {
400 bd_printbsdslice(od, (daddr_t)dp->dp_start, prefix, verbose);
404 sprintf(line, "%s: Linux swap %.6dMB (%d - %d)\n",
405 prefix, dp->dp_size / 2048,
406 dp->dp_start, dp->dp_start + dp->dp_size);
408 sprintf(line, "%s: Linux swap\n", prefix);
413 * read the superblock to confirm this is an ext2fs partition?
416 sprintf(line, "%s: ext2fs %.6dMB (%d - %d)\n", prefix,
417 dp->dp_size / 2048, dp->dp_start,
418 dp->dp_start + dp->dp_size);
420 sprintf(line, "%s: ext2fs\n", prefix);
422 case 0x00: /* unused partition */
427 sprintf(line, "%s: FAT-12 %.6dMB (%d - %d)\n", prefix,
428 dp->dp_size / 2048, dp->dp_start,
429 dp->dp_start + dp->dp_size);
431 sprintf(line, "%s: FAT-12\n", prefix);
437 sprintf(line, "%s: FAT-16 %.6dMB (%d - %d)\n", prefix,
438 dp->dp_size / 2048, dp->dp_start,
439 dp->dp_start + dp->dp_size);
441 sprintf(line, "%s: FAT-16\n", prefix);
446 sprintf(line, "%s: FAT-32 %.6dMB (%d - %d)\n", prefix,
447 dp->dp_size / 2048, dp->dp_start,
448 dp->dp_start + dp->dp_size);
450 sprintf(line, "%s: FAT-32\n", prefix);
454 sprintf(line, "%s: Unknown fs: 0x%x %.6dMB (%d - %d)\n",
455 prefix, dp->dp_typ, dp->dp_size / 2048,
456 dp->dp_start, dp->dp_start + dp->dp_size);
458 sprintf(line, "%s: Unknown fs: 0x%x\n", prefix,
465 * Print out each valid partition in the disklabel of a FreeBSD slice.
466 * For size calculations, we assume a 512 byte sector size.
469 bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix,
473 char buf[BIOSDISK_SECSIZE];
474 struct disklabel *lp;
478 if (bd_read(od, offset + LABELSECTOR, 1, buf))
480 lp =(struct disklabel *)(&buf[0]);
481 if (lp->d_magic != DISKMAGIC) {
482 sprintf(line, "%s: FFS bad disklabel\n", prefix);
487 /* Print partitions */
488 for (i = 0; i < lp->d_npartitions; i++) {
490 * For each partition, make sure we know what type of fs it is. If
491 * not, then skip it. However, since floppies often have bogus
492 * fstypes, print the 'a' partition on a floppy even if it is marked
495 if ((lp->d_partitions[i].p_fstype == FS_BSDFFS) ||
496 (lp->d_partitions[i].p_fstype == FS_SWAP) ||
497 (lp->d_partitions[i].p_fstype == FS_VINUM) ||
498 ((lp->d_partitions[i].p_fstype == FS_UNUSED) &&
499 (od->od_flags & BD_FLOPPY) && (i == 0))) {
501 /* Only print out statistics in verbose mode */
503 sprintf(line, " %s%c: %s %.6dMB (%d - %d)\n", prefix, 'a' + i,
504 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap" :
505 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" :
507 lp->d_partitions[i].p_size / 2048,
508 lp->d_partitions[i].p_offset,
509 lp->d_partitions[i].p_offset + lp->d_partitions[i].p_size);
511 sprintf(line, " %s%c: %s\n", prefix, 'a' + i,
512 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap" :
513 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" :
522 * Attempt to open the disk described by (dev) for use by (f).
524 * Note that the philosophy here is "give them exactly what
525 * they ask for". This is necessary because being too "smart"
526 * about what the user might want leads to complications.
527 * (eg. given no slice or partition value, with a disk that is
528 * sliced - are they after the first BSD slice, or the DOS
532 bd_open(struct open_file *f, ...)
535 struct i386_devdesc *dev;
536 struct open_disk *od;
540 dev = va_arg(ap, struct i386_devdesc *);
542 if ((error = bd_opendisk(&od, dev)))
548 ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od;
549 DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff);
554 bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev)
556 struct open_disk *od;
559 if (dev->d_unit >= nbdinfo) {
560 DEBUG("attempt to open nonexistent disk");
564 od = (struct open_disk *)malloc(sizeof(struct open_disk));
570 /* Look up BIOS unit number, intialise open_disk structure */
571 od->od_dkunit = dev->d_unit;
572 od->od_unit = bdinfo[od->od_dkunit].bd_unit;
573 od->od_flags = bdinfo[od->od_dkunit].bd_flags;
576 DEBUG("open '%s', unit 0x%x slice %d partition %d",
577 i386_fmtdev(dev), dev->d_unit,
578 dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition);
580 /* Get geometry for this open (removable device may have changed) */
581 if (bd_getgeom(od)) {
582 DEBUG("can't get geometry");
587 /* Determine disk layout. */
588 #ifdef LOADER_GPT_SUPPORT
589 error = bd_open_gpt(od, dev);
592 error = bd_open_mbr(od, dev);
598 *odp = od; /* return the open disk */
604 bd_open_mbr(struct open_disk *od, struct i386_devdesc *dev)
606 struct dos_partition *dptr;
607 struct disklabel *lp;
608 int sector, slice, i;
613 * Following calculations attempt to determine the correct value
614 * for d->od_boff by looking for the slice and partition specified,
615 * or searching for reasonable defaults.
619 * Find the slice in the DOS slice table.
622 if (bd_read(od, 0, 1, buf)) {
623 DEBUG("error reading MBR");
628 * Check the slice table magic.
630 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
631 /* If a slice number was explicitly supplied, this is an error */
632 if (dev->d_kind.biosdisk.slice > 0) {
633 DEBUG("no slice table/MBR (no magic)");
637 goto unsliced; /* may be a floppy */
641 * copy the partition table, then pick up any extended partitions.
643 bcopy(buf + DOSPARTOFF, &od->od_slicetab,
644 sizeof(struct dos_partition) * NDOSPART);
645 od->od_nslices = 4; /* extended slices start here */
646 for (i = 0; i < NDOSPART; i++)
647 bd_checkextended(od, i);
648 od->od_flags |= BD_PARTTABOK;
649 dptr = &od->od_slicetab[0];
651 /* Is this a request for the whole disk? */
652 if (dev->d_kind.biosdisk.slice == -1) {
658 * if a slice number was supplied but not found, this is an error.
660 if (dev->d_kind.biosdisk.slice > 0) {
661 slice = dev->d_kind.biosdisk.slice - 1;
662 if (slice >= od->od_nslices) {
663 DEBUG("slice %d not found", slice);
669 * Check for the historically bogus MBR found on true dedicated disks
671 if ((dptr[3].dp_typ == DOSPTYP_386BSD) &&
672 (dptr[3].dp_start == 0) &&
673 (dptr[3].dp_size == 50000)) {
678 /* Try to auto-detect the best slice; this should always give a slice number */
679 if (dev->d_kind.biosdisk.slice == 0) {
680 slice = bd_bestslice(od);
684 dev->d_kind.biosdisk.slice = slice;
687 dptr = &od->od_slicetab[0];
689 * Accept the supplied slice number unequivocally (we may be looking
690 * at a DOS partition).
692 dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */
693 sector = dptr->dp_start;
694 DEBUG("slice entry %d at %d, %d sectors", dev->d_kind.biosdisk.slice - 1, sector, dptr->dp_size);
697 * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition
699 if ((dptr->dp_typ == DOSPTYP_386BSD) && (dev->d_kind.biosdisk.partition < 0))
700 dev->d_kind.biosdisk.partition = 0;
704 * Now we have the slice offset, look for the partition in the disklabel if we have
705 * a partition to start with.
707 * XXX we might want to check the label checksum.
709 if (dev->d_kind.biosdisk.partition < 0) {
710 od->od_boff = sector; /* no partition, must be after the slice */
711 DEBUG("opening raw slice");
714 if (bd_read(od, sector + LABELSECTOR, 1, buf)) {
715 DEBUG("error reading disklabel");
718 DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel), buf + LABELOFFSET, &od->od_disklabel);
719 bcopy(buf + LABELOFFSET, &od->od_disklabel, sizeof(struct disklabel));
720 lp = &od->od_disklabel;
721 od->od_flags |= BD_LABELOK;
723 if (lp->d_magic != DISKMAGIC) {
724 DEBUG("no disklabel");
727 if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) {
728 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
729 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions);
734 /* Complain if the partition is unused unless this is a floppy. */
735 if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) &&
736 !(od->od_flags & BD_FLOPPY))
737 DEBUG("warning, partition marked as unused");
741 lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset -
742 lp->d_partitions[RAW_PART].p_offset +
749 bd_checkextended(struct open_disk *od, int slicenum)
751 char buf[BIOSDISK_SECSIZE];
752 struct dos_partition *dp;
756 dp = &od->od_slicetab[slicenum];
757 start = od->od_nslices;
759 if (dp->dp_size == 0)
761 if (dp->dp_typ != DOSPTYP_EXT)
763 if (bd_read(od, (daddr_t)dp->dp_start, 1, buf))
765 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
766 DEBUG("no magic in extended table");
770 dp = (struct dos_partition *)(&buf[DOSPARTOFF]);
771 for (i = 0; i < NDOSPART; i++, dp++) {
772 if (dp->dp_size == 0)
774 if (od->od_nslices == NEXTDOSPART)
776 dp->dp_start += base;
777 bcopy(dp, &od->od_slicetab[od->od_nslices], sizeof(*dp));
780 end = od->od_nslices;
783 * now, recursively check the slices we just added
785 for (i = start; i < end; i++)
786 bd_checkextended(od, i);
792 * Search for a slice with the following preferences:
794 * 1: Active FreeBSD slice
795 * 2: Non-active FreeBSD slice
796 * 3: Active Linux slice
797 * 4: non-active Linux slice
798 * 5: Active FAT/FAT32 slice
799 * 6: non-active FAT/FAT32 slice
801 #define PREF_RAWDISK 0
802 #define PREF_FBSD_ACT 1
804 #define PREF_LINUX_ACT 3
806 #define PREF_DOS_ACT 5
811 * slicelimit is in the range 0 .. NDOSPART
814 bd_bestslice(struct open_disk *od)
816 struct dos_partition *dp;
821 preflevel = PREF_NONE;
823 dp = &od->od_slicetab[0];
824 for (i = 0; i < od->od_nslices; i++, dp++) {
826 switch (dp->dp_typ) {
827 case DOSPTYP_386BSD: /* FreeBSD */
828 pref = dp->dp_flag & 0x80 ? PREF_FBSD_ACT : PREF_FBSD;
832 pref = dp->dp_flag & 0x80 ? PREF_LINUX_ACT : PREF_LINUX;
835 case 0x01: /* DOS/Windows */
841 pref = dp->dp_flag & 0x80 ? PREF_DOS_ACT : PREF_DOS;
847 if (pref < preflevel) {
855 #ifdef LOADER_GPT_SUPPORT
857 bd_open_gpt(struct open_disk *od, struct i386_devdesc *dev)
859 struct dos_partition *dp;
863 int entries_per_sec, error, i, part;
865 char gpt[BIOSDISK_SECSIZE], tbl[BIOSDISK_SECSIZE];
868 * Following calculations attempt to determine the correct value
869 * for d->od_boff by looking for the slice and partition specified,
870 * or searching for reasonable defaults.
874 /* First, read the MBR and see if we have a PMBR. */
875 if (bd_read(od, 0, 1, tbl)) {
876 DEBUG("error reading MBR");
880 /* Check the slice table magic. */
881 if (((u_char)tbl[0x1fe] != 0x55) || ((u_char)tbl[0x1ff] != 0xaa))
884 /* Check for GPT slice. */
886 dp = (struct dos_partition *)(tbl + DOSPARTOFF);
887 for (i = 0; i < NDOSPART; i++) {
888 if (dp[i].dp_typ == 0xee)
890 else if (dp[i].dp_typ != 0x00)
896 /* Read primary GPT table header. */
897 if (bd_read(od, 1, 1, gpt)) {
898 DEBUG("error reading GPT header");
901 hdr = (struct gpt_hdr *)gpt;
902 if (bcmp(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig)) != 0 ||
903 hdr->hdr_lba_self != 1 || hdr->hdr_revision < 0x00010000 ||
904 hdr->hdr_entsz < sizeof(*ent) ||
905 BIOSDISK_SECSIZE % hdr->hdr_entsz != 0) {
906 DEBUG("Invalid GPT header\n");
910 /* Now walk the partition table to count the number of valid partitions. */
912 entries_per_sec = BIOSDISK_SECSIZE / hdr->hdr_entsz;
913 elba = hdr->hdr_lba_table + hdr->hdr_entries / entries_per_sec;
914 for (lba = hdr->hdr_lba_table; lba < elba; lba++) {
915 if (bd_read(od, lba, 1, tbl)) {
916 DEBUG("error reading GPT table");
919 for (i = 0; i < entries_per_sec; i++) {
920 ent = (struct gpt_ent *)(tbl + i * hdr->hdr_entsz);
921 if (uuid_is_nil(&ent->ent_type, NULL) || ent->ent_lba_start == 0 ||
922 ent->ent_lba_end < ent->ent_lba_start)
928 /* Save the important information about all the valid partitions. */
929 od->od_nparts = part;
931 od->od_partitions = malloc(part * sizeof(struct gpt_part));
933 for (lba = hdr->hdr_lba_table; lba < elba; lba++) {
934 if (bd_read(od, lba, 1, tbl)) {
935 DEBUG("error reading GPT table");
939 for (i = 0; i < entries_per_sec; i++) {
940 ent = (struct gpt_ent *)(tbl + i * hdr->hdr_entsz);
941 if (uuid_is_nil(&ent->ent_type, NULL) ||
942 ent->ent_lba_start == 0 ||
943 ent->ent_lba_end < ent->ent_lba_start)
945 od->od_partitions[part].gp_index = (lba - hdr->hdr_lba_table) *
946 entries_per_sec + i + 1;
947 od->od_partitions[part].gp_type = ent->ent_type;
948 od->od_partitions[part].gp_start = ent->ent_lba_start;
949 od->od_partitions[part].gp_end = ent->ent_lba_end;
954 od->od_flags |= BD_GPTOK;
956 /* Is this a request for the whole disk? */
957 if (dev->d_kind.biosdisk.slice < 0) {
963 * If a partition number was supplied, then the user is trying to use
964 * an MBR address rather than a GPT address, so fail.
966 if (dev->d_kind.biosdisk.partition != 0xff) {
971 /* If a slice number was supplied but not found, this is an error. */
973 if (dev->d_kind.biosdisk.slice > 0) {
974 for (i = 0; i < od->od_nparts; i++) {
975 if (od->od_partitions[i].gp_index == dev->d_kind.biosdisk.slice) {
976 gp = &od->od_partitions[i];
981 DEBUG("partition %d not found", dev->d_kind.biosdisk.slice);
987 /* Try to auto-detect the best partition. */
988 if (dev->d_kind.biosdisk.slice == 0) {
989 gp = bd_best_gptpart(od);
994 dev->d_kind.biosdisk.slice = gp->gp_index;
996 od->od_boff = gp->gp_start;
1000 free(od->od_partitions);
1004 static struct gpt_part *
1005 bd_best_gptpart(struct open_disk *od)
1007 struct gpt_part *gp, *prefpart;
1008 int i, pref, preflevel;
1011 preflevel = PREF_NONE;
1013 gp = od->od_partitions;
1014 for (i = 0; i < od->od_nparts; i++, gp++) {
1015 /* Windows. XXX: Also Linux. */
1016 if (uuid_equal(&gp->gp_type, &ms_basic_data, NULL))
1019 else if (uuid_equal(&gp->gp_type, &freebsd_ufs, NULL) ||
1020 uuid_equal(&gp->gp_type, &freebsd_zfs, NULL))
1024 if (pref < preflevel) {
1034 bd_close(struct open_file *f)
1036 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data);
1043 bd_closedisk(struct open_disk *od)
1045 DEBUG("open_disk %p", od);
1047 /* XXX is this required? (especially if disk already open...) */
1048 if (od->od_flags & BD_FLOPPY)
1051 #ifdef LOADER_GPT_SUPPORT
1052 if (od->od_flags & BD_GPTOK)
1053 free(od->od_partitions);
1059 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
1061 struct bcache_devdata bcd;
1062 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
1064 bcd.dv_strategy = bd_realstrategy;
1065 bcd.dv_devdata = devdata;
1066 return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize));
1070 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
1072 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
1074 #ifdef BD_SUPPORT_FRAGS
1075 char fragbuf[BIOSDISK_SECSIZE];
1078 fragsize = size % BIOSDISK_SECSIZE;
1080 if (size % BIOSDISK_SECSIZE)
1081 panic("bd_strategy: %d bytes I/O not multiple of block size", size);
1084 DEBUG("open_disk %p", od);
1085 blks = size / BIOSDISK_SECSIZE;
1091 DEBUG("read %d from %d to %p", blks, dblk, buf);
1093 if (blks && bd_read(od, dblk, blks, buf)) {
1094 DEBUG("read error");
1097 #ifdef BD_SUPPORT_FRAGS
1098 DEBUG("bd_strategy: frag read %d from %d+%d to %p",
1099 fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE));
1100 if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) {
1101 DEBUG("frag read error");
1104 bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize);
1108 DEBUG("write %d from %d to %p", blks, dblk, buf);
1110 if (blks && bd_write(od, dblk, blks, buf)) {
1111 DEBUG("write error");
1114 #ifdef BD_SUPPORT_FRAGS
1116 DEBUG("Attempted to write a frag");
1131 /* Max number of sectors to bounce-buffer if the request crosses a 64k boundary */
1132 #define FLOPPY_BOUNCEBUF 18
1135 bd_edd_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write)
1137 static struct edd_packet packet;
1140 packet.count = blks;
1141 packet.offset = VTOPOFF(dest);
1142 packet.seg = VTOPSEG(dest);
1144 v86.ctl = V86_FLAGS;
1147 /* Should we Write with verify ?? 0x4302 ? */
1151 v86.edx = od->od_unit;
1152 v86.ds = VTOPSEG(&packet);
1153 v86.esi = VTOPOFF(&packet);
1155 return (v86.efl & 0x1);
1159 bd_chs_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write)
1161 u_int x, bpc, cyl, hd, sec;
1163 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1165 cyl = x / bpc; /* block # / blocks per cylinder */
1166 x %= bpc; /* block offset into cylinder */
1167 hd = x / od->od_sec; /* offset / blocks per track */
1168 sec = x % od->od_sec; /* offset into track */
1170 /* correct sector number for 1-based BIOS numbering */
1174 /* CHS doesn't support cylinders > 1023. */
1177 v86.ctl = V86_FLAGS;
1180 v86.eax = 0x300 | blks;
1182 v86.eax = 0x200 | blks;
1183 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1184 v86.edx = (hd << 8) | od->od_unit;
1185 v86.es = VTOPSEG(dest);
1186 v86.ebx = VTOPOFF(dest);
1188 return (v86.efl & 0x1);
1192 bd_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write)
1194 u_int x, sec, result, resid, retry, maxfer;
1195 caddr_t p, xp, bbuf, breg;
1197 /* Just in case some idiot actually tries to read/write -1 blocks... */
1204 /* Decide whether we have to bounce */
1205 if (VTOP(dest) >> 20 != 0 || ((od->od_unit < 0x80) &&
1206 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16)))) {
1209 * There is a 64k physical boundary somewhere in the
1210 * destination buffer, or the destination buffer is above
1211 * first 1MB of physical memory so we have to arrange a
1212 * suitable bounce buffer. Allocate a buffer twice as large
1213 * as we need to. Use the bottom half unless there is a break
1214 * there, in which case we use the top half.
1216 x = min(FLOPPY_BOUNCEBUF, (unsigned)blks);
1217 bbuf = alloca(x * 2 * BIOSDISK_SECSIZE);
1218 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) ==
1219 ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) {
1222 breg = bbuf + x * BIOSDISK_SECSIZE;
1224 maxfer = x; /* limit transfers to bounce region size */
1232 * Play it safe and don't cross track boundaries.
1233 * (XXX this is probably unnecessary)
1235 sec = dblk % od->od_sec; /* offset into track */
1236 x = min(od->od_sec - sec, resid);
1238 x = min(x, maxfer); /* fit bounce buffer */
1240 /* where do we transfer to? */
1241 xp = bbuf == NULL ? p : breg;
1244 * Put your Data In, Put your Data out,
1245 * Put your Data In, and shake it all about
1247 if (write && bbuf != NULL)
1248 bcopy(p, breg, x * BIOSDISK_SECSIZE);
1251 * Loop retrying the operation a couple of times. The BIOS
1254 for (retry = 0; retry < 3; retry++) {
1255 /* if retrying, reset the drive */
1257 v86.ctl = V86_FLAGS;
1260 v86.edx = od->od_unit;
1264 if (od->od_flags & BD_MODEEDD1)
1265 result = bd_edd_io(od, dblk, x, xp, write);
1267 result = bd_chs_io(od, dblk, x, xp, write);
1273 DEBUG("%d sectors from %lld to %p (0x%x) %s", x, dblk, p, VTOP(p),
1274 result ? "failed" : "ok");
1276 DEBUG("%d sectors from %p (0x%x) to %lld %s", x, p, VTOP(p), dblk,
1277 result ? "failed" : "ok");
1281 if (!write && bbuf != NULL)
1282 bcopy(breg, p, x * BIOSDISK_SECSIZE);
1283 p += (x * BIOSDISK_SECSIZE);
1288 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1293 bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1296 return (bd_io(od, dblk, blks, dest, 0));
1300 bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1303 return (bd_io(od, dblk, blks, dest, 1));
1307 bd_getgeom(struct open_disk *od)
1310 v86.ctl = V86_FLAGS;
1313 v86.edx = od->od_unit;
1316 if ((v86.efl & 0x1) || /* carry set */
1317 ((v86.edx & 0xff) <= (unsigned)(od->od_unit & 0x7f))) /* unit # bad */
1320 /* convert max cyl # -> # of cylinders */
1321 od->od_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1;
1322 /* convert max head # -> # of heads */
1323 od->od_hds = ((v86.edx & 0xff00) >> 8) + 1;
1324 od->od_sec = v86.ecx & 0x3f;
1326 DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec);
1331 * Return the BIOS geometry of a given "fixed drive" in a format
1332 * suitable for the legacy bootinfo structure. Since the kernel is
1333 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we
1334 * prefer to get the information directly, rather than rely on being
1335 * able to put it together from information already maintained for
1336 * different purposes and for a probably different number of drives.
1338 * For valid drives, the geometry is expected in the format (31..0)
1339 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are
1340 * indicated by returning the geometry of a "1.2M" PC-format floppy
1341 * disk. And, incidentally, what is returned is not the geometry as
1342 * such but the highest valid cylinder, head, and sector numbers.
1345 bd_getbigeom(int bunit)
1348 v86.ctl = V86_FLAGS;
1351 v86.edx = 0x80 + bunit;
1355 return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
1356 (v86.edx & 0xff00) | (v86.ecx & 0x3f);
1360 * Return a suitable dev_t value for (dev).
1362 * In the case where it looks like (dev) is a SCSI disk, we allow the number of
1363 * IDE disks to be specified in $num_ide_disks. There should be a Better Way.
1366 bd_getdev(struct i386_devdesc *dev)
1368 struct open_disk *od;
1373 int unitofs = 0, i, unit;
1375 biosdev = bd_unit2bios(dev->d_unit);
1376 DEBUG("unit %d BIOS device %d", dev->d_unit, biosdev);
1377 if (biosdev == -1) /* not a BIOS device */
1379 if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */
1382 if (biosdev < 0x80) {
1383 /* floppy (or emulated floppy) or ATAPI device */
1384 if (bdinfo[dev->d_unit].bd_type == DT_ATAPI) {
1385 /* is an ATAPI disk */
1388 /* is a floppy disk */
1393 if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) {
1394 /* label OK, disk labelled as SCSI */
1396 /* check for unit number correction hint, now deprecated */
1397 if ((nip = getenv("num_ide_disks")) != NULL) {
1398 i = strtol(nip, &cp, 0);
1399 /* check for parse error */
1400 if ((cp != nip) && (*cp == 0))
1404 /* assume an IDE disk */
1408 /* default root disk unit number */
1409 unit = (biosdev & 0x7f) - unitofs;
1411 /* XXX a better kludge to set the root disk unit number */
1412 if ((nip = getenv("root_disk_unit")) != NULL) {
1413 i = strtol(nip, &cp, 0);
1414 /* check for parse error */
1415 if ((cp != nip) && (*cp == 0))
1419 rootdev = MAKEBOOTDEV(major, dev->d_kind.biosdisk.slice + 1, unit,
1420 dev->d_kind.biosdisk.partition);
1421 DEBUG("dev is 0x%x\n", rootdev);