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>
55 #define BIOS_NUMDRIVES 0x475
56 #define BIOSDISK_SECSIZE 512
57 #define BUFSIZE (1 * BIOSDISK_SECSIZE)
58 #define MAXBDDEV MAXDEV
60 #define DT_ATAPI 0x10 /* disk type for ATAPI floppies */
61 #define WDMAJOR 0 /* major numbers for devices we frontend for */
67 # define DEBUG(fmt, args...) printf("%s: " fmt "\n" , __func__ , ## args)
69 # define DEBUG(fmt, args...)
72 #ifdef LOADER_GPT_SUPPORT
82 int od_dkunit; /* disk unit number */
83 int od_unit; /* BIOS unit number */
84 int od_cyl; /* BIOS geometry */
87 daddr_t od_boff; /* block offset from beginning of BIOS disk */
89 #define BD_MODEINT13 0x0000
90 #define BD_MODEEDD1 0x0001
91 #define BD_MODEEDD3 0x0002
92 #define BD_MODEMASK 0x0003
93 #define BD_FLOPPY 0x0004
94 #define BD_LABELOK 0x0008
95 #define BD_PARTTABOK 0x0010
96 #ifdef LOADER_GPT_SUPPORT
97 #define BD_GPTOK 0x0020
101 struct disklabel mbr_disklabel;
102 int mbr_nslices; /* slice count */
103 struct dos_partition mbr_slicetab[NEXTDOSPART];
105 #ifdef LOADER_GPT_SUPPORT
108 struct gpt_part *gpt_partitions;
114 #define od_disklabel _data._mbr.mbr_disklabel
115 #define od_nslices _data._mbr.mbr_nslices
116 #define od_slicetab _data._mbr.mbr_slicetab
117 #ifdef LOADER_GPT_SUPPORT
118 #define od_nparts _data._gpt.gpt_nparts
119 #define od_partitions _data._gpt.gpt_partitions
123 * List of BIOS devices, translation from disk unit number to
128 int bd_unit; /* BIOS unit number */
130 int bd_type; /* BIOS 'drive type' (floppy only) */
132 static int nbdinfo = 0;
134 static int bd_getgeom(struct open_disk *od);
135 static int bd_read(struct open_disk *od, daddr_t dblk, int blks,
137 static int bd_write(struct open_disk *od, daddr_t dblk, int blks,
140 static int bd_int13probe(struct bdinfo *bd);
142 #ifdef LOADER_GPT_SUPPORT
143 static void bd_printgptpart(struct open_disk *od, struct gpt_part *gp,
144 char *prefix, int verbose);
146 static void bd_printslice(struct open_disk *od, struct dos_partition *dp,
147 char *prefix, int verbose);
148 static void bd_printbsdslice(struct open_disk *od, daddr_t offset,
149 char *prefix, int verbose);
151 static int bd_init(void);
152 static int bd_strategy(void *devdata, int flag, daddr_t dblk,
153 size_t size, char *buf, size_t *rsize);
154 static int bd_realstrategy(void *devdata, int flag, daddr_t dblk,
155 size_t size, char *buf, size_t *rsize);
156 static int bd_open(struct open_file *f, ...);
157 static int bd_close(struct open_file *f);
158 static void bd_print(int verbose);
160 struct devsw biosdisk = {
172 static int bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev);
173 static void bd_closedisk(struct open_disk *od);
174 static int bd_open_mbr(struct open_disk *od, struct i386_devdesc *dev);
175 static int bd_bestslice(struct open_disk *od);
176 static void bd_checkextended(struct open_disk *od, int slicenum);
177 #ifdef LOADER_GPT_SUPPORT
178 static int bd_open_gpt(struct open_disk *od, struct i386_devdesc *dev);
179 static struct gpt_part *bd_best_gptpart(struct open_disk *od);
183 * Translate between BIOS device numbers and our private unit numbers.
186 bd_bios2unit(int biosdev)
190 DEBUG("looking for bios device 0x%x", biosdev);
191 for (i = 0; i < nbdinfo; i++) {
192 DEBUG("bd unit %d is BIOS device 0x%x", i, bdinfo[i].bd_unit);
193 if (bdinfo[i].bd_unit == biosdev)
200 bd_unit2bios(int unit)
202 if ((unit >= 0) && (unit < nbdinfo))
203 return(bdinfo[unit].bd_unit);
208 * Quiz the BIOS for disk devices, save a little info about them.
213 int base, unit, nfd = 0;
215 /* sequence 0, 0x80 */
216 for (base = 0; base <= 0x80; base += 0x80) {
217 for (unit = base; (nbdinfo < MAXBDDEV); unit++) {
219 /* check the BIOS equipment list for number of fixed disks */
221 (nfd >= *(unsigned char *)PTOV(BIOS_NUMDRIVES)))
225 bdinfo[nbdinfo].bd_unit = unit;
226 bdinfo[nbdinfo].bd_flags = (unit < 0x80) ? BD_FLOPPY : 0;
228 if (!bd_int13probe(&bdinfo[nbdinfo]))
231 /* XXX we need "disk aliases" to make this simpler */
232 printf("BIOS drive %c: is disk%d\n",
233 (unit < 0x80) ? ('A' + unit) : ('C' + unit - 0x80), nbdinfo);
243 * Try to detect a device supported by the legacy int13 BIOS
246 bd_int13probe(struct bdinfo *bd)
251 v86.edx = bd->bd_unit;
254 if (!(v86.efl & 0x1) && /* carry clear */
255 ((v86.edx & 0xff) > ((unsigned)bd->bd_unit & 0x7f))) { /* unit # OK */
256 if ((v86.ecx & 0x3f) == 0) { /* absurd sector size */
257 DEBUG("Invalid geometry for unit %d", bd->bd_unit);
258 return(0); /* skip device */
260 bd->bd_flags |= BD_MODEINT13;
261 bd->bd_type = v86.ebx & 0xff;
263 /* Determine if we can use EDD with this device. */
265 v86.edx = bd->bd_unit;
268 if (!(v86.efl & 0x1) && /* carry clear */
269 ((v86.ebx & 0xffff) == 0xaa55) && /* signature */
270 (v86.ecx & EDD_INTERFACE_FIXED_DISK)) { /* packets mode ok */
271 bd->bd_flags |= BD_MODEEDD1;
272 if((v86.eax & 0xff00) >= 0x3000)
273 bd->bd_flags |= BD_MODEEDD3;
281 * Print information about disks
284 bd_print(int verbose)
288 struct i386_devdesc dev;
289 struct open_disk *od;
290 struct dos_partition *dptr;
292 for (i = 0; i < nbdinfo; i++) {
293 sprintf(line, " disk%d: BIOS drive %c:\n", i,
294 (bdinfo[i].bd_unit < 0x80) ? ('A' + bdinfo[i].bd_unit) : ('C' + bdinfo[i].bd_unit - 0x80));
297 /* try to open the whole disk */
299 dev.d_kind.biosdisk.slice = -1;
300 dev.d_kind.biosdisk.partition = -1;
302 if (!bd_opendisk(&od, &dev)) {
304 #ifdef LOADER_GPT_SUPPORT
305 /* Do we have a GPT table? */
306 if (od->od_flags & BD_GPTOK) {
307 for (j = 0; j < od->od_nparts; j++) {
308 sprintf(line, " disk%dp%d", i,
309 od->od_partitions[j].gp_index);
310 bd_printgptpart(od, &od->od_partitions[j], line, verbose);
314 /* Do we have a partition table? */
315 if (od->od_flags & BD_PARTTABOK) {
316 dptr = &od->od_slicetab[0];
318 /* Check for a "dedicated" disk */
319 if ((dptr[3].dp_typ == DOSPTYP_386BSD) &&
320 (dptr[3].dp_start == 0) &&
321 (dptr[3].dp_size == 50000)) {
322 sprintf(line, " disk%d", i);
323 bd_printbsdslice(od, 0, line, verbose);
325 for (j = 0; j < od->od_nslices; j++) {
326 sprintf(line, " disk%ds%d", i, j + 1);
327 bd_printslice(od, &dptr[j], line, verbose);
336 /* Given a size in 512 byte sectors, convert it to a human-readable number. */
338 display_size(uint64_t size)
345 if (size >= 10485760000LL) {
348 } else if (size >= 10240000) {
351 } else if (size >= 10000) {
355 sprintf(buf, "%.6ld%cB", (long)size, unit);
359 #ifdef LOADER_GPT_SUPPORT
360 static uuid_t efi = GPT_ENT_TYPE_EFI;
361 static uuid_t freebsd_boot = GPT_ENT_TYPE_FREEBSD_BOOT;
362 static uuid_t freebsd_ufs = GPT_ENT_TYPE_FREEBSD_UFS;
363 static uuid_t freebsd_swap = GPT_ENT_TYPE_FREEBSD_SWAP;
364 static uuid_t freebsd_zfs = GPT_ENT_TYPE_FREEBSD_ZFS;
365 static uuid_t ms_basic_data = GPT_ENT_TYPE_MS_BASIC_DATA;
368 bd_printgptpart(struct open_disk *od, struct gpt_part *gp, char *prefix,
375 sprintf(stats, " %s", display_size(gp->gp_end + 1 - gp->gp_start));
379 if (uuid_equal(&gp->gp_type, &efi, NULL))
380 sprintf(line, "%s: EFI %s\n", prefix, stats);
381 else if (uuid_equal(&gp->gp_type, &ms_basic_data, NULL))
382 sprintf(line, "%s: FAT/NTFS %s\n", prefix, stats);
383 else if (uuid_equal(&gp->gp_type, &freebsd_boot, NULL))
384 sprintf(line, "%s: FreeBSD boot%s\n", prefix, stats);
385 else if (uuid_equal(&gp->gp_type, &freebsd_ufs, NULL))
386 sprintf(line, "%s: FreeBSD UFS %s\n", prefix, stats);
387 else if (uuid_equal(&gp->gp_type, &freebsd_zfs, NULL))
388 sprintf(line, "%s: FreeBSD ZFS %s\n", prefix, stats);
389 else if (uuid_equal(&gp->gp_type, &freebsd_swap, NULL))
390 sprintf(line, "%s: FreeBSD swap%s\n", prefix, stats);
392 sprintf(line, "%s: %08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x%s\n",
394 gp->gp_type.time_low, gp->gp_type.time_mid,
395 gp->gp_type.time_hi_and_version,
396 gp->gp_type.clock_seq_hi_and_reserved, gp->gp_type.clock_seq_low,
397 gp->gp_type.node[0], gp->gp_type.node[1], gp->gp_type.node[2],
398 gp->gp_type.node[3], gp->gp_type.node[4], gp->gp_type.node[5],
405 * Print information about slices on a disk. For the size calculations we
406 * assume a 512 byte sector.
409 bd_printslice(struct open_disk *od, struct dos_partition *dp, char *prefix,
416 sprintf(stats, " %s (%d - %d)", display_size(dp->dp_size),
417 dp->dp_start, dp->dp_start + dp->dp_size);
421 switch (dp->dp_typ) {
423 bd_printbsdslice(od, (daddr_t)dp->dp_start, prefix, verbose);
426 sprintf(line, "%s: Linux swap%s\n", prefix, stats);
431 * read the superblock to confirm this is an ext2fs partition?
433 sprintf(line, "%s: ext2fs%s\n", prefix, stats);
435 case 0x00: /* unused partition */
439 sprintf(line, "%s: FAT-12%s\n", prefix, stats);
444 sprintf(line, "%s: FAT-16%s\n", prefix, stats);
447 sprintf(line, "%s: NTFS/HPFS%s\n", prefix, stats);
451 sprintf(line, "%s: FAT-32%s\n", prefix, stats);
454 sprintf(line, "%s: Unknown fs: 0x%x %s\n", prefix, dp->dp_typ,
461 * Print out each valid partition in the disklabel of a FreeBSD slice.
462 * For size calculations, we assume a 512 byte sector size.
465 bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix,
469 char buf[BIOSDISK_SECSIZE];
470 struct disklabel *lp;
474 if (bd_read(od, offset + LABELSECTOR, 1, buf))
476 lp =(struct disklabel *)(&buf[0]);
477 if (lp->d_magic != DISKMAGIC) {
478 sprintf(line, "%s: FFS bad disklabel\n", prefix);
483 /* Print partitions */
484 for (i = 0; i < lp->d_npartitions; i++) {
486 * For each partition, make sure we know what type of fs it is. If
487 * not, then skip it. However, since floppies often have bogus
488 * fstypes, print the 'a' partition on a floppy even if it is marked
491 if ((lp->d_partitions[i].p_fstype == FS_BSDFFS) ||
492 (lp->d_partitions[i].p_fstype == FS_SWAP) ||
493 (lp->d_partitions[i].p_fstype == FS_VINUM) ||
494 ((lp->d_partitions[i].p_fstype == FS_UNUSED) &&
495 (od->od_flags & BD_FLOPPY) && (i == 0))) {
497 /* Only print out statistics in verbose mode */
499 sprintf(line, " %s%c: %s %s (%d - %d)\n", prefix, 'a' + i,
500 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap " :
501 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" :
503 display_size(lp->d_partitions[i].p_size),
504 lp->d_partitions[i].p_offset,
505 lp->d_partitions[i].p_offset + lp->d_partitions[i].p_size);
507 sprintf(line, " %s%c: %s\n", prefix, 'a' + i,
508 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap" :
509 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" :
518 * Attempt to open the disk described by (dev) for use by (f).
520 * Note that the philosophy here is "give them exactly what
521 * they ask for". This is necessary because being too "smart"
522 * about what the user might want leads to complications.
523 * (eg. given no slice or partition value, with a disk that is
524 * sliced - are they after the first BSD slice, or the DOS
528 bd_open(struct open_file *f, ...)
531 struct i386_devdesc *dev;
532 struct open_disk *od;
536 dev = va_arg(ap, struct i386_devdesc *);
538 if ((error = bd_opendisk(&od, dev)))
544 ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od;
545 DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff);
550 bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev)
552 struct open_disk *od;
555 if (dev->d_unit >= nbdinfo) {
556 DEBUG("attempt to open nonexistent disk");
560 od = (struct open_disk *)malloc(sizeof(struct open_disk));
566 /* Look up BIOS unit number, intialise open_disk structure */
567 od->od_dkunit = dev->d_unit;
568 od->od_unit = bdinfo[od->od_dkunit].bd_unit;
569 od->od_flags = bdinfo[od->od_dkunit].bd_flags;
572 DEBUG("open '%s', unit 0x%x slice %d partition %d",
573 i386_fmtdev(dev), dev->d_unit,
574 dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition);
576 /* Get geometry for this open (removable device may have changed) */
577 if (bd_getgeom(od)) {
578 DEBUG("can't get geometry");
583 /* Determine disk layout. */
584 #ifdef LOADER_GPT_SUPPORT
585 error = bd_open_gpt(od, dev);
588 error = bd_open_mbr(od, dev);
594 *odp = od; /* return the open disk */
600 bd_open_mbr(struct open_disk *od, struct i386_devdesc *dev)
602 struct dos_partition *dptr;
603 struct disklabel *lp;
604 int sector, slice, i;
609 * Following calculations attempt to determine the correct value
610 * for d->od_boff by looking for the slice and partition specified,
611 * or searching for reasonable defaults.
615 * Find the slice in the DOS slice table.
618 if (bd_read(od, 0, 1, buf)) {
619 DEBUG("error reading MBR");
624 * Check the slice table magic.
626 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
627 /* If a slice number was explicitly supplied, this is an error */
628 if (dev->d_kind.biosdisk.slice > 0) {
629 DEBUG("no slice table/MBR (no magic)");
633 goto unsliced; /* may be a floppy */
637 * copy the partition table, then pick up any extended partitions.
639 bcopy(buf + DOSPARTOFF, &od->od_slicetab,
640 sizeof(struct dos_partition) * NDOSPART);
641 od->od_nslices = 4; /* extended slices start here */
642 for (i = 0; i < NDOSPART; i++)
643 bd_checkextended(od, i);
644 od->od_flags |= BD_PARTTABOK;
645 dptr = &od->od_slicetab[0];
647 /* Is this a request for the whole disk? */
648 if (dev->d_kind.biosdisk.slice == -1) {
654 * if a slice number was supplied but not found, this is an error.
656 if (dev->d_kind.biosdisk.slice > 0) {
657 slice = dev->d_kind.biosdisk.slice - 1;
658 if (slice >= od->od_nslices) {
659 DEBUG("slice %d not found", slice);
665 * Check for the historically bogus MBR found on true dedicated disks
667 if ((dptr[3].dp_typ == DOSPTYP_386BSD) &&
668 (dptr[3].dp_start == 0) &&
669 (dptr[3].dp_size == 50000)) {
674 /* Try to auto-detect the best slice; this should always give a slice number */
675 if (dev->d_kind.biosdisk.slice == 0) {
676 slice = bd_bestslice(od);
680 dev->d_kind.biosdisk.slice = slice;
683 dptr = &od->od_slicetab[0];
685 * Accept the supplied slice number unequivocally (we may be looking
686 * at a DOS partition).
688 dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */
689 sector = dptr->dp_start;
690 DEBUG("slice entry %d at %d, %d sectors", dev->d_kind.biosdisk.slice - 1, sector, dptr->dp_size);
693 * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition
695 if ((dptr->dp_typ == DOSPTYP_386BSD) && (dev->d_kind.biosdisk.partition < 0))
696 dev->d_kind.biosdisk.partition = 0;
700 * Now we have the slice offset, look for the partition in the disklabel if we have
701 * a partition to start with.
703 * XXX we might want to check the label checksum.
705 if (dev->d_kind.biosdisk.partition < 0) {
706 od->od_boff = sector; /* no partition, must be after the slice */
707 DEBUG("opening raw slice");
710 if (bd_read(od, sector + LABELSECTOR, 1, buf)) {
711 DEBUG("error reading disklabel");
714 DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel), buf + LABELOFFSET, &od->od_disklabel);
715 bcopy(buf + LABELOFFSET, &od->od_disklabel, sizeof(struct disklabel));
716 lp = &od->od_disklabel;
717 od->od_flags |= BD_LABELOK;
719 if (lp->d_magic != DISKMAGIC) {
720 DEBUG("no disklabel");
723 if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) {
724 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
725 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions);
730 /* Complain if the partition is unused unless this is a floppy. */
731 if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) &&
732 !(od->od_flags & BD_FLOPPY))
733 DEBUG("warning, partition marked as unused");
737 lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset -
738 lp->d_partitions[RAW_PART].p_offset +
745 bd_checkextended(struct open_disk *od, int slicenum)
747 char buf[BIOSDISK_SECSIZE];
748 struct dos_partition *dp;
752 dp = &od->od_slicetab[slicenum];
753 start = od->od_nslices;
755 if (dp->dp_size == 0)
757 if (dp->dp_typ != DOSPTYP_EXT)
759 if (bd_read(od, (daddr_t)dp->dp_start, 1, buf))
761 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
762 DEBUG("no magic in extended table");
766 dp = (struct dos_partition *)(&buf[DOSPARTOFF]);
767 for (i = 0; i < NDOSPART; i++, dp++) {
768 if (dp->dp_size == 0)
770 if (od->od_nslices == NEXTDOSPART)
772 dp->dp_start += base;
773 bcopy(dp, &od->od_slicetab[od->od_nslices], sizeof(*dp));
776 end = od->od_nslices;
779 * now, recursively check the slices we just added
781 for (i = start; i < end; i++)
782 bd_checkextended(od, i);
788 * Search for a slice with the following preferences:
790 * 1: Active FreeBSD slice
791 * 2: Non-active FreeBSD slice
792 * 3: Active Linux slice
793 * 4: non-active Linux slice
794 * 5: Active FAT/FAT32 slice
795 * 6: non-active FAT/FAT32 slice
797 #define PREF_RAWDISK 0
798 #define PREF_FBSD_ACT 1
800 #define PREF_LINUX_ACT 3
802 #define PREF_DOS_ACT 5
807 * slicelimit is in the range 0 .. NDOSPART
810 bd_bestslice(struct open_disk *od)
812 struct dos_partition *dp;
817 preflevel = PREF_NONE;
819 dp = &od->od_slicetab[0];
820 for (i = 0; i < od->od_nslices; i++, dp++) {
822 switch (dp->dp_typ) {
823 case DOSPTYP_386BSD: /* FreeBSD */
824 pref = dp->dp_flag & 0x80 ? PREF_FBSD_ACT : PREF_FBSD;
828 pref = dp->dp_flag & 0x80 ? PREF_LINUX_ACT : PREF_LINUX;
831 case 0x01: /* DOS/Windows */
837 pref = dp->dp_flag & 0x80 ? PREF_DOS_ACT : PREF_DOS;
843 if (pref < preflevel) {
851 #ifdef LOADER_GPT_SUPPORT
853 bd_open_gpt(struct open_disk *od, struct i386_devdesc *dev)
855 struct dos_partition *dp;
859 int entries_per_sec, error, i, part;
861 char gpt[BIOSDISK_SECSIZE], tbl[BIOSDISK_SECSIZE];
864 * Following calculations attempt to determine the correct value
865 * for d->od_boff by looking for the slice and partition specified,
866 * or searching for reasonable defaults.
870 /* First, read the MBR and see if we have a PMBR. */
871 if (bd_read(od, 0, 1, tbl)) {
872 DEBUG("error reading MBR");
876 /* Check the slice table magic. */
877 if (((u_char)tbl[0x1fe] != 0x55) || ((u_char)tbl[0x1ff] != 0xaa))
880 /* Check for GPT slice. */
882 dp = (struct dos_partition *)(tbl + DOSPARTOFF);
883 for (i = 0; i < NDOSPART; i++) {
884 if (dp[i].dp_typ == 0xee)
886 else if ((part != 1) && (dp[i].dp_typ != 0x00))
892 /* Read primary GPT table header. */
893 if (bd_read(od, 1, 1, gpt)) {
894 DEBUG("error reading GPT header");
897 hdr = (struct gpt_hdr *)gpt;
898 if (bcmp(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig)) != 0 ||
899 hdr->hdr_lba_self != 1 || hdr->hdr_revision < 0x00010000 ||
900 hdr->hdr_entsz < sizeof(*ent) ||
901 BIOSDISK_SECSIZE % hdr->hdr_entsz != 0) {
902 DEBUG("Invalid GPT header\n");
906 /* Now walk the partition table to count the number of valid partitions. */
908 entries_per_sec = BIOSDISK_SECSIZE / hdr->hdr_entsz;
909 elba = hdr->hdr_lba_table + hdr->hdr_entries / entries_per_sec;
910 for (lba = hdr->hdr_lba_table; lba < elba; lba++) {
911 if (bd_read(od, lba, 1, tbl)) {
912 DEBUG("error reading GPT table");
915 for (i = 0; i < entries_per_sec; i++) {
916 ent = (struct gpt_ent *)(tbl + i * hdr->hdr_entsz);
917 if (uuid_is_nil(&ent->ent_type, NULL) || ent->ent_lba_start == 0 ||
918 ent->ent_lba_end < ent->ent_lba_start)
924 /* Save the important information about all the valid partitions. */
925 od->od_nparts = part;
927 od->od_partitions = malloc(part * sizeof(struct gpt_part));
929 for (lba = hdr->hdr_lba_table; lba < elba; lba++) {
930 if (bd_read(od, lba, 1, tbl)) {
931 DEBUG("error reading GPT table");
935 for (i = 0; i < entries_per_sec; i++) {
936 ent = (struct gpt_ent *)(tbl + i * hdr->hdr_entsz);
937 if (uuid_is_nil(&ent->ent_type, NULL) ||
938 ent->ent_lba_start == 0 ||
939 ent->ent_lba_end < ent->ent_lba_start)
941 od->od_partitions[part].gp_index = (lba - hdr->hdr_lba_table) *
942 entries_per_sec + i + 1;
943 od->od_partitions[part].gp_type = ent->ent_type;
944 od->od_partitions[part].gp_start = ent->ent_lba_start;
945 od->od_partitions[part].gp_end = ent->ent_lba_end;
950 od->od_flags |= BD_GPTOK;
952 /* Is this a request for the whole disk? */
953 if (dev->d_kind.biosdisk.slice < 0) {
959 * If a partition number was supplied, then the user is trying to use
960 * an MBR address rather than a GPT address, so fail.
962 if (dev->d_kind.biosdisk.partition != 0xff) {
967 /* If a slice number was supplied but not found, this is an error. */
969 if (dev->d_kind.biosdisk.slice > 0) {
970 for (i = 0; i < od->od_nparts; i++) {
971 if (od->od_partitions[i].gp_index == dev->d_kind.biosdisk.slice) {
972 gp = &od->od_partitions[i];
977 DEBUG("partition %d not found", dev->d_kind.biosdisk.slice);
983 /* Try to auto-detect the best partition. */
984 if (dev->d_kind.biosdisk.slice == 0) {
985 gp = bd_best_gptpart(od);
990 dev->d_kind.biosdisk.slice = gp->gp_index;
992 od->od_boff = gp->gp_start;
996 if (od->od_nparts > 0)
997 free(od->od_partitions);
998 od->od_flags &= ~BD_GPTOK;
1003 static struct gpt_part *
1004 bd_best_gptpart(struct open_disk *od)
1006 struct gpt_part *gp, *prefpart;
1007 int i, pref, preflevel;
1010 preflevel = PREF_NONE;
1012 gp = od->od_partitions;
1013 for (i = 0; i < od->od_nparts; i++, gp++) {
1014 /* Windows. XXX: Also Linux. */
1015 if (uuid_equal(&gp->gp_type, &ms_basic_data, NULL))
1018 else if (uuid_equal(&gp->gp_type, &freebsd_ufs, NULL) ||
1019 uuid_equal(&gp->gp_type, &freebsd_zfs, NULL))
1023 if (pref < preflevel) {
1033 bd_close(struct open_file *f)
1035 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data);
1042 bd_closedisk(struct open_disk *od)
1044 DEBUG("open_disk %p", od);
1046 /* XXX is this required? (especially if disk already open...) */
1047 if (od->od_flags & BD_FLOPPY)
1050 #ifdef LOADER_GPT_SUPPORT
1051 if (od->od_flags & BD_GPTOK && od->od_nparts > 0)
1052 free(od->od_partitions);
1058 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
1060 struct bcache_devdata bcd;
1061 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
1063 bcd.dv_strategy = bd_realstrategy;
1064 bcd.dv_devdata = devdata;
1065 return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize));
1069 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
1071 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
1073 #ifdef BD_SUPPORT_FRAGS
1074 char fragbuf[BIOSDISK_SECSIZE];
1077 fragsize = size % BIOSDISK_SECSIZE;
1079 if (size % BIOSDISK_SECSIZE)
1080 panic("bd_strategy: %d bytes I/O not multiple of block size", size);
1083 DEBUG("open_disk %p", od);
1084 blks = size / BIOSDISK_SECSIZE;
1090 DEBUG("read %d from %lld to %p", blks, dblk, buf);
1092 if (blks && bd_read(od, dblk, blks, buf)) {
1093 DEBUG("read error");
1096 #ifdef BD_SUPPORT_FRAGS
1097 DEBUG("bd_strategy: frag read %d from %d+%d to %p",
1098 fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE));
1099 if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) {
1100 DEBUG("frag read error");
1103 bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize);
1107 DEBUG("write %d from %d to %p", blks, dblk, buf);
1109 if (blks && bd_write(od, dblk, blks, buf)) {
1110 DEBUG("write error");
1113 #ifdef BD_SUPPORT_FRAGS
1115 DEBUG("Attempted to write a frag");
1130 /* Max number of sectors to bounce-buffer if the request crosses a 64k boundary */
1131 #define FLOPPY_BOUNCEBUF 18
1134 bd_edd_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write)
1136 static struct edd_packet packet;
1138 packet.len = sizeof(struct edd_packet);
1139 packet.count = blks;
1140 packet.off = VTOPOFF(dest);
1141 packet.seg = VTOPSEG(dest);
1143 v86.ctl = V86_FLAGS;
1146 /* Should we Write with verify ?? 0x4302 ? */
1150 v86.edx = od->od_unit;
1151 v86.ds = VTOPSEG(&packet);
1152 v86.esi = VTOPOFF(&packet);
1154 return (v86.efl & 0x1);
1158 bd_chs_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write)
1160 u_int x, bpc, cyl, hd, sec;
1162 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1164 cyl = x / bpc; /* block # / blocks per cylinder */
1165 x %= bpc; /* block offset into cylinder */
1166 hd = x / od->od_sec; /* offset / blocks per track */
1167 sec = x % od->od_sec; /* offset into track */
1169 /* correct sector number for 1-based BIOS numbering */
1173 /* CHS doesn't support cylinders > 1023. */
1176 v86.ctl = V86_FLAGS;
1179 v86.eax = 0x300 | blks;
1181 v86.eax = 0x200 | blks;
1182 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1183 v86.edx = (hd << 8) | od->od_unit;
1184 v86.es = VTOPSEG(dest);
1185 v86.ebx = VTOPOFF(dest);
1187 return (v86.efl & 0x1);
1191 bd_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write)
1193 u_int x, sec, result, resid, retry, maxfer;
1194 caddr_t p, xp, bbuf, breg;
1196 /* Just in case some idiot actually tries to read/write -1 blocks... */
1203 /* Decide whether we have to bounce */
1204 if (VTOP(dest) >> 20 != 0 || ((od->od_unit < 0x80) &&
1205 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16)))) {
1208 * There is a 64k physical boundary somewhere in the
1209 * destination buffer, or the destination buffer is above
1210 * first 1MB of physical memory so we have to arrange a
1211 * suitable bounce buffer. Allocate a buffer twice as large
1212 * as we need to. Use the bottom half unless there is a break
1213 * there, in which case we use the top half.
1215 x = min(FLOPPY_BOUNCEBUF, (unsigned)blks);
1216 bbuf = alloca(x * 2 * BIOSDISK_SECSIZE);
1217 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) ==
1218 ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) {
1221 breg = bbuf + x * BIOSDISK_SECSIZE;
1223 maxfer = x; /* limit transfers to bounce region size */
1231 * Play it safe and don't cross track boundaries.
1232 * (XXX this is probably unnecessary)
1234 sec = dblk % od->od_sec; /* offset into track */
1235 x = min(od->od_sec - sec, resid);
1237 x = min(x, maxfer); /* fit bounce buffer */
1239 /* where do we transfer to? */
1240 xp = bbuf == NULL ? p : breg;
1243 * Put your Data In, Put your Data out,
1244 * Put your Data In, and shake it all about
1246 if (write && bbuf != NULL)
1247 bcopy(p, breg, x * BIOSDISK_SECSIZE);
1250 * Loop retrying the operation a couple of times. The BIOS
1253 for (retry = 0; retry < 3; retry++) {
1254 /* if retrying, reset the drive */
1256 v86.ctl = V86_FLAGS;
1259 v86.edx = od->od_unit;
1263 if (od->od_flags & BD_MODEEDD1)
1264 result = bd_edd_io(od, dblk, x, xp, write);
1266 result = bd_chs_io(od, dblk, x, xp, write);
1272 DEBUG("Write %d sector(s) from %p (0x%x) to %lld %s", x,
1273 p, VTOP(p), dblk, result ? "failed" : "ok");
1275 DEBUG("Read %d sector(s) from %lld to %p (0x%x) %s", x,
1276 dblk, p, VTOP(p), result ? "failed" : "ok");
1280 if (!write && bbuf != NULL)
1281 bcopy(breg, p, x * BIOSDISK_SECSIZE);
1282 p += (x * BIOSDISK_SECSIZE);
1287 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1292 bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1295 return (bd_io(od, dblk, blks, dest, 0));
1299 bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1302 return (bd_io(od, dblk, blks, dest, 1));
1306 bd_getgeom(struct open_disk *od)
1309 v86.ctl = V86_FLAGS;
1312 v86.edx = od->od_unit;
1315 if ((v86.efl & 0x1) || /* carry set */
1316 ((v86.edx & 0xff) <= (unsigned)(od->od_unit & 0x7f))) /* unit # bad */
1319 /* convert max cyl # -> # of cylinders */
1320 od->od_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1;
1321 /* convert max head # -> # of heads */
1322 od->od_hds = ((v86.edx & 0xff00) >> 8) + 1;
1323 od->od_sec = v86.ecx & 0x3f;
1325 DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec);
1330 * Return the BIOS geometry of a given "fixed drive" in a format
1331 * suitable for the legacy bootinfo structure. Since the kernel is
1332 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we
1333 * prefer to get the information directly, rather than rely on being
1334 * able to put it together from information already maintained for
1335 * different purposes and for a probably different number of drives.
1337 * For valid drives, the geometry is expected in the format (31..0)
1338 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are
1339 * indicated by returning the geometry of a "1.2M" PC-format floppy
1340 * disk. And, incidentally, what is returned is not the geometry as
1341 * such but the highest valid cylinder, head, and sector numbers.
1344 bd_getbigeom(int bunit)
1347 v86.ctl = V86_FLAGS;
1350 v86.edx = 0x80 + bunit;
1354 return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
1355 (v86.edx & 0xff00) | (v86.ecx & 0x3f);
1359 * Return a suitable dev_t value for (dev).
1361 * In the case where it looks like (dev) is a SCSI disk, we allow the number of
1362 * IDE disks to be specified in $num_ide_disks. There should be a Better Way.
1365 bd_getdev(struct i386_devdesc *dev)
1367 struct open_disk *od;
1372 int unitofs = 0, i, unit;
1374 biosdev = bd_unit2bios(dev->d_unit);
1375 DEBUG("unit %d BIOS device %d", dev->d_unit, biosdev);
1376 if (biosdev == -1) /* not a BIOS device */
1378 if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */
1381 if (biosdev < 0x80) {
1382 /* floppy (or emulated floppy) or ATAPI device */
1383 if (bdinfo[dev->d_unit].bd_type == DT_ATAPI) {
1384 /* is an ATAPI disk */
1387 /* is a floppy disk */
1392 if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) {
1393 /* label OK, disk labelled as SCSI */
1395 /* check for unit number correction hint, now deprecated */
1396 if ((nip = getenv("num_ide_disks")) != NULL) {
1397 i = strtol(nip, &cp, 0);
1398 /* check for parse error */
1399 if ((cp != nip) && (*cp == 0))
1403 /* assume an IDE disk */
1407 /* default root disk unit number */
1408 unit = (biosdev & 0x7f) - unitofs;
1410 /* XXX a better kludge to set the root disk unit number */
1411 if ((nip = getenv("root_disk_unit")) != NULL) {
1412 i = strtol(nip, &cp, 0);
1413 /* check for parse error */
1414 if ((cp != nip) && (*cp == 0))
1418 rootdev = MAKEBOOTDEV(major, dev->d_kind.biosdisk.slice + 1, unit,
1419 dev->d_kind.biosdisk.partition);
1420 DEBUG("dev is 0x%x\n", rootdev);