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 daddr_t 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 /* Given a size in 512 byte sectors, convert it to a human-readable number. */
335 display_size(uint64_t size)
342 if (size >= 10485760000LL) {
345 } else if (size >= 10240000) {
348 } else if (size >= 10000) {
352 sprintf(buf, "%.6ld%cB", (long)size, unit);
356 #ifdef LOADER_GPT_SUPPORT
357 static uuid_t efi = GPT_ENT_TYPE_EFI;
358 static uuid_t freebsd_boot = GPT_ENT_TYPE_FREEBSD_BOOT;
359 static uuid_t freebsd_ufs = GPT_ENT_TYPE_FREEBSD_UFS;
360 static uuid_t freebsd_swap = GPT_ENT_TYPE_FREEBSD_SWAP;
361 static uuid_t freebsd_zfs = GPT_ENT_TYPE_FREEBSD_ZFS;
362 static uuid_t ms_basic_data = GPT_ENT_TYPE_MS_BASIC_DATA;
365 bd_printgptpart(struct open_disk *od, struct gpt_part *gp, char *prefix,
372 sprintf(stats, " %s", display_size(gp->gp_end + 1 - gp->gp_start));
376 if (uuid_equal(&gp->gp_type, &efi, NULL))
377 sprintf(line, "%s: EFI %s\n", prefix, stats);
378 else if (uuid_equal(&gp->gp_type, &ms_basic_data, NULL))
379 sprintf(line, "%s: FAT/NTFS %s\n", prefix, stats);
380 else if (uuid_equal(&gp->gp_type, &freebsd_boot, NULL))
381 sprintf(line, "%s: FreeBSD boot%s\n", prefix, stats);
382 else if (uuid_equal(&gp->gp_type, &freebsd_ufs, NULL))
383 sprintf(line, "%s: FreeBSD UFS %s\n", prefix, stats);
384 else if (uuid_equal(&gp->gp_type, &freebsd_zfs, NULL))
385 sprintf(line, "%s: FreeBSD ZFS %s\n", prefix, stats);
386 else if (uuid_equal(&gp->gp_type, &freebsd_swap, NULL))
387 sprintf(line, "%s: FreeBSD swap%s\n", prefix, stats);
389 sprintf(line, "%s: %08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x%s\n",
391 gp->gp_type.time_low, gp->gp_type.time_mid,
392 gp->gp_type.time_hi_and_version,
393 gp->gp_type.clock_seq_hi_and_reserved, gp->gp_type.clock_seq_low,
394 gp->gp_type.node[0], gp->gp_type.node[1], gp->gp_type.node[2],
395 gp->gp_type.node[3], gp->gp_type.node[4], gp->gp_type.node[5],
402 * Print information about slices on a disk. For the size calculations we
403 * assume a 512 byte sector.
406 bd_printslice(struct open_disk *od, struct dos_partition *dp, char *prefix,
413 sprintf(stats, " %s (%d - %d)", display_size(dp->dp_size),
414 dp->dp_start, dp->dp_start + dp->dp_size);
418 switch (dp->dp_typ) {
420 bd_printbsdslice(od, (daddr_t)dp->dp_start, prefix, verbose);
423 sprintf(line, "%s: Linux swap%s\n", prefix, stats);
428 * read the superblock to confirm this is an ext2fs partition?
430 sprintf(line, "%s: ext2fs%s\n", prefix, stats);
432 case 0x00: /* unused partition */
436 sprintf(line, "%s: FAT-12%s\n", prefix, stats);
441 sprintf(line, "%s: FAT-16%s\n", prefix, stats);
444 sprintf(line, "%s: NTFS/HPFS%s\n", prefix, stats);
448 sprintf(line, "%s: FAT-32%s\n", prefix, stats);
451 sprintf(line, "%s: Unknown fs: 0x%x %s\n", prefix, dp->dp_typ,
458 * Print out each valid partition in the disklabel of a FreeBSD slice.
459 * For size calculations, we assume a 512 byte sector size.
462 bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix,
466 char buf[BIOSDISK_SECSIZE];
467 struct disklabel *lp;
471 if (bd_read(od, offset + LABELSECTOR, 1, buf))
473 lp =(struct disklabel *)(&buf[0]);
474 if (lp->d_magic != DISKMAGIC) {
475 sprintf(line, "%s: FFS bad disklabel\n", prefix);
480 /* Print partitions */
481 for (i = 0; i < lp->d_npartitions; i++) {
483 * For each partition, make sure we know what type of fs it is. If
484 * not, then skip it. However, since floppies often have bogus
485 * fstypes, print the 'a' partition on a floppy even if it is marked
488 if ((lp->d_partitions[i].p_fstype == FS_BSDFFS) ||
489 (lp->d_partitions[i].p_fstype == FS_SWAP) ||
490 (lp->d_partitions[i].p_fstype == FS_VINUM) ||
491 ((lp->d_partitions[i].p_fstype == FS_UNUSED) &&
492 (od->od_flags & BD_FLOPPY) && (i == 0))) {
494 /* Only print out statistics in verbose mode */
496 sprintf(line, " %s%c: %s %s (%d - %d)\n", prefix, 'a' + i,
497 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap " :
498 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" :
500 display_size(lp->d_partitions[i].p_size),
501 lp->d_partitions[i].p_offset,
502 lp->d_partitions[i].p_offset + lp->d_partitions[i].p_size);
504 sprintf(line, " %s%c: %s\n", prefix, 'a' + i,
505 (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap" :
506 (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" :
515 * Attempt to open the disk described by (dev) for use by (f).
517 * Note that the philosophy here is "give them exactly what
518 * they ask for". This is necessary because being too "smart"
519 * about what the user might want leads to complications.
520 * (eg. given no slice or partition value, with a disk that is
521 * sliced - are they after the first BSD slice, or the DOS
525 bd_open(struct open_file *f, ...)
528 struct i386_devdesc *dev;
529 struct open_disk *od;
533 dev = va_arg(ap, struct i386_devdesc *);
535 if ((error = bd_opendisk(&od, dev)))
541 ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od;
542 DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff);
547 bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev)
549 struct open_disk *od;
552 if (dev->d_unit >= nbdinfo) {
553 DEBUG("attempt to open nonexistent disk");
557 od = (struct open_disk *)malloc(sizeof(struct open_disk));
563 /* Look up BIOS unit number, intialise open_disk structure */
564 od->od_dkunit = dev->d_unit;
565 od->od_unit = bdinfo[od->od_dkunit].bd_unit;
566 od->od_flags = bdinfo[od->od_dkunit].bd_flags;
569 DEBUG("open '%s', unit 0x%x slice %d partition %d",
570 i386_fmtdev(dev), dev->d_unit,
571 dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition);
573 /* Get geometry for this open (removable device may have changed) */
574 if (bd_getgeom(od)) {
575 DEBUG("can't get geometry");
580 /* Determine disk layout. */
581 #ifdef LOADER_GPT_SUPPORT
582 error = bd_open_gpt(od, dev);
585 error = bd_open_mbr(od, dev);
591 *odp = od; /* return the open disk */
597 bd_open_mbr(struct open_disk *od, struct i386_devdesc *dev)
599 struct dos_partition *dptr;
600 struct disklabel *lp;
601 int sector, slice, i;
606 * Following calculations attempt to determine the correct value
607 * for d->od_boff by looking for the slice and partition specified,
608 * or searching for reasonable defaults.
612 * Find the slice in the DOS slice table.
615 if (bd_read(od, 0, 1, buf)) {
616 DEBUG("error reading MBR");
621 * Check the slice table magic.
623 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
624 /* If a slice number was explicitly supplied, this is an error */
625 if (dev->d_kind.biosdisk.slice > 0) {
626 DEBUG("no slice table/MBR (no magic)");
630 goto unsliced; /* may be a floppy */
634 * copy the partition table, then pick up any extended partitions.
636 bcopy(buf + DOSPARTOFF, &od->od_slicetab,
637 sizeof(struct dos_partition) * NDOSPART);
638 od->od_nslices = 4; /* extended slices start here */
639 for (i = 0; i < NDOSPART; i++)
640 bd_checkextended(od, i);
641 od->od_flags |= BD_PARTTABOK;
642 dptr = &od->od_slicetab[0];
644 /* Is this a request for the whole disk? */
645 if (dev->d_kind.biosdisk.slice == -1) {
651 * if a slice number was supplied but not found, this is an error.
653 if (dev->d_kind.biosdisk.slice > 0) {
654 slice = dev->d_kind.biosdisk.slice - 1;
655 if (slice >= od->od_nslices) {
656 DEBUG("slice %d not found", slice);
662 * Check for the historically bogus MBR found on true dedicated disks
664 if ((dptr[3].dp_typ == DOSPTYP_386BSD) &&
665 (dptr[3].dp_start == 0) &&
666 (dptr[3].dp_size == 50000)) {
671 /* Try to auto-detect the best slice; this should always give a slice number */
672 if (dev->d_kind.biosdisk.slice == 0) {
673 slice = bd_bestslice(od);
677 dev->d_kind.biosdisk.slice = slice;
680 dptr = &od->od_slicetab[0];
682 * Accept the supplied slice number unequivocally (we may be looking
683 * at a DOS partition).
685 dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */
686 sector = dptr->dp_start;
687 DEBUG("slice entry %d at %d, %d sectors", dev->d_kind.biosdisk.slice - 1, sector, dptr->dp_size);
690 * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition
692 if ((dptr->dp_typ == DOSPTYP_386BSD) && (dev->d_kind.biosdisk.partition < 0))
693 dev->d_kind.biosdisk.partition = 0;
697 * Now we have the slice offset, look for the partition in the disklabel if we have
698 * a partition to start with.
700 * XXX we might want to check the label checksum.
702 if (dev->d_kind.biosdisk.partition < 0) {
703 od->od_boff = sector; /* no partition, must be after the slice */
704 DEBUG("opening raw slice");
707 if (bd_read(od, sector + LABELSECTOR, 1, buf)) {
708 DEBUG("error reading disklabel");
711 DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel), buf + LABELOFFSET, &od->od_disklabel);
712 bcopy(buf + LABELOFFSET, &od->od_disklabel, sizeof(struct disklabel));
713 lp = &od->od_disklabel;
714 od->od_flags |= BD_LABELOK;
716 if (lp->d_magic != DISKMAGIC) {
717 DEBUG("no disklabel");
720 if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) {
721 DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
722 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions);
727 /* Complain if the partition is unused unless this is a floppy. */
728 if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) &&
729 !(od->od_flags & BD_FLOPPY))
730 DEBUG("warning, partition marked as unused");
734 lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset -
735 lp->d_partitions[RAW_PART].p_offset +
742 bd_checkextended(struct open_disk *od, int slicenum)
744 char buf[BIOSDISK_SECSIZE];
745 struct dos_partition *dp;
749 dp = &od->od_slicetab[slicenum];
750 start = od->od_nslices;
752 if (dp->dp_size == 0)
754 if (dp->dp_typ != DOSPTYP_EXT)
756 if (bd_read(od, (daddr_t)dp->dp_start, 1, buf))
758 if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) {
759 DEBUG("no magic in extended table");
763 dp = (struct dos_partition *)(&buf[DOSPARTOFF]);
764 for (i = 0; i < NDOSPART; i++, dp++) {
765 if (dp->dp_size == 0)
767 if (od->od_nslices == NEXTDOSPART)
769 dp->dp_start += base;
770 bcopy(dp, &od->od_slicetab[od->od_nslices], sizeof(*dp));
773 end = od->od_nslices;
776 * now, recursively check the slices we just added
778 for (i = start; i < end; i++)
779 bd_checkextended(od, i);
785 * Search for a slice with the following preferences:
787 * 1: Active FreeBSD slice
788 * 2: Non-active FreeBSD slice
789 * 3: Active Linux slice
790 * 4: non-active Linux slice
791 * 5: Active FAT/FAT32 slice
792 * 6: non-active FAT/FAT32 slice
794 #define PREF_RAWDISK 0
795 #define PREF_FBSD_ACT 1
797 #define PREF_LINUX_ACT 3
799 #define PREF_DOS_ACT 5
804 * slicelimit is in the range 0 .. NDOSPART
807 bd_bestslice(struct open_disk *od)
809 struct dos_partition *dp;
814 preflevel = PREF_NONE;
816 dp = &od->od_slicetab[0];
817 for (i = 0; i < od->od_nslices; i++, dp++) {
819 switch (dp->dp_typ) {
820 case DOSPTYP_386BSD: /* FreeBSD */
821 pref = dp->dp_flag & 0x80 ? PREF_FBSD_ACT : PREF_FBSD;
825 pref = dp->dp_flag & 0x80 ? PREF_LINUX_ACT : PREF_LINUX;
828 case 0x01: /* DOS/Windows */
834 pref = dp->dp_flag & 0x80 ? PREF_DOS_ACT : PREF_DOS;
840 if (pref < preflevel) {
848 #ifdef LOADER_GPT_SUPPORT
850 bd_open_gpt(struct open_disk *od, struct i386_devdesc *dev)
852 struct dos_partition *dp;
856 int entries_per_sec, error, i, part;
858 char gpt[BIOSDISK_SECSIZE], tbl[BIOSDISK_SECSIZE];
861 * Following calculations attempt to determine the correct value
862 * for d->od_boff by looking for the slice and partition specified,
863 * or searching for reasonable defaults.
867 /* First, read the MBR and see if we have a PMBR. */
868 if (bd_read(od, 0, 1, tbl)) {
869 DEBUG("error reading MBR");
873 /* Check the slice table magic. */
874 if (((u_char)tbl[0x1fe] != 0x55) || ((u_char)tbl[0x1ff] != 0xaa))
877 /* Check for GPT slice. */
879 dp = (struct dos_partition *)(tbl + DOSPARTOFF);
880 for (i = 0; i < NDOSPART; i++) {
881 if (dp[i].dp_typ == 0xee)
883 else if ((part != 1) && (dp[i].dp_typ != 0x00))
889 /* Read primary GPT table header. */
890 if (bd_read(od, 1, 1, gpt)) {
891 DEBUG("error reading GPT header");
894 hdr = (struct gpt_hdr *)gpt;
895 if (bcmp(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig)) != 0 ||
896 hdr->hdr_lba_self != 1 || hdr->hdr_revision < 0x00010000 ||
897 hdr->hdr_entsz < sizeof(*ent) ||
898 BIOSDISK_SECSIZE % hdr->hdr_entsz != 0) {
899 DEBUG("Invalid GPT header\n");
903 /* Now walk the partition table to count the number of valid partitions. */
905 entries_per_sec = BIOSDISK_SECSIZE / hdr->hdr_entsz;
906 elba = hdr->hdr_lba_table + hdr->hdr_entries / entries_per_sec;
907 for (lba = hdr->hdr_lba_table; lba < elba; lba++) {
908 if (bd_read(od, lba, 1, tbl)) {
909 DEBUG("error reading GPT table");
912 for (i = 0; i < entries_per_sec; i++) {
913 ent = (struct gpt_ent *)(tbl + i * hdr->hdr_entsz);
914 if (uuid_is_nil(&ent->ent_type, NULL) || ent->ent_lba_start == 0 ||
915 ent->ent_lba_end < ent->ent_lba_start)
921 /* Save the important information about all the valid partitions. */
922 od->od_nparts = part;
924 od->od_partitions = malloc(part * sizeof(struct gpt_part));
926 for (lba = hdr->hdr_lba_table; lba < elba; lba++) {
927 if (bd_read(od, lba, 1, tbl)) {
928 DEBUG("error reading GPT table");
932 for (i = 0; i < entries_per_sec; i++) {
933 ent = (struct gpt_ent *)(tbl + i * hdr->hdr_entsz);
934 if (uuid_is_nil(&ent->ent_type, NULL) ||
935 ent->ent_lba_start == 0 ||
936 ent->ent_lba_end < ent->ent_lba_start)
938 od->od_partitions[part].gp_index = (lba - hdr->hdr_lba_table) *
939 entries_per_sec + i + 1;
940 od->od_partitions[part].gp_type = ent->ent_type;
941 od->od_partitions[part].gp_start = ent->ent_lba_start;
942 od->od_partitions[part].gp_end = ent->ent_lba_end;
947 od->od_flags |= BD_GPTOK;
949 /* Is this a request for the whole disk? */
950 if (dev->d_kind.biosdisk.slice < 0) {
956 * If a partition number was supplied, then the user is trying to use
957 * an MBR address rather than a GPT address, so fail.
959 if (dev->d_kind.biosdisk.partition != 0xff) {
964 /* If a slice number was supplied but not found, this is an error. */
966 if (dev->d_kind.biosdisk.slice > 0) {
967 for (i = 0; i < od->od_nparts; i++) {
968 if (od->od_partitions[i].gp_index == dev->d_kind.biosdisk.slice) {
969 gp = &od->od_partitions[i];
974 DEBUG("partition %d not found", dev->d_kind.biosdisk.slice);
980 /* Try to auto-detect the best partition. */
981 if (dev->d_kind.biosdisk.slice == 0) {
982 gp = bd_best_gptpart(od);
987 dev->d_kind.biosdisk.slice = gp->gp_index;
989 od->od_boff = gp->gp_start;
993 if (od->od_nparts > 0)
994 free(od->od_partitions);
995 od->od_flags &= ~BD_GPTOK;
1000 static struct gpt_part *
1001 bd_best_gptpart(struct open_disk *od)
1003 struct gpt_part *gp, *prefpart;
1004 int i, pref, preflevel;
1007 preflevel = PREF_NONE;
1009 gp = od->od_partitions;
1010 for (i = 0; i < od->od_nparts; i++, gp++) {
1011 /* Windows. XXX: Also Linux. */
1012 if (uuid_equal(&gp->gp_type, &ms_basic_data, NULL))
1015 else if (uuid_equal(&gp->gp_type, &freebsd_ufs, NULL) ||
1016 uuid_equal(&gp->gp_type, &freebsd_zfs, NULL))
1020 if (pref < preflevel) {
1030 bd_close(struct open_file *f)
1032 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data);
1039 bd_closedisk(struct open_disk *od)
1041 DEBUG("open_disk %p", od);
1043 /* XXX is this required? (especially if disk already open...) */
1044 if (od->od_flags & BD_FLOPPY)
1047 #ifdef LOADER_GPT_SUPPORT
1048 if (od->od_flags & BD_GPTOK && od->od_nparts > 0)
1049 free(od->od_partitions);
1055 bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
1057 struct bcache_devdata bcd;
1058 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
1060 bcd.dv_strategy = bd_realstrategy;
1061 bcd.dv_devdata = devdata;
1062 return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize));
1066 bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
1068 struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data);
1070 #ifdef BD_SUPPORT_FRAGS
1071 char fragbuf[BIOSDISK_SECSIZE];
1074 fragsize = size % BIOSDISK_SECSIZE;
1076 if (size % BIOSDISK_SECSIZE)
1077 panic("bd_strategy: %d bytes I/O not multiple of block size", size);
1080 DEBUG("open_disk %p", od);
1081 blks = size / BIOSDISK_SECSIZE;
1087 DEBUG("read %d from %lld to %p", blks, dblk, buf);
1089 if (blks && bd_read(od, dblk, blks, buf)) {
1090 DEBUG("read error");
1093 #ifdef BD_SUPPORT_FRAGS
1094 DEBUG("bd_strategy: frag read %d from %d+%d to %p",
1095 fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE));
1096 if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) {
1097 DEBUG("frag read error");
1100 bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize);
1104 DEBUG("write %d from %d to %p", blks, dblk, buf);
1106 if (blks && bd_write(od, dblk, blks, buf)) {
1107 DEBUG("write error");
1110 #ifdef BD_SUPPORT_FRAGS
1112 DEBUG("Attempted to write a frag");
1127 /* Max number of sectors to bounce-buffer if the request crosses a 64k boundary */
1128 #define FLOPPY_BOUNCEBUF 18
1131 bd_edd_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write)
1133 static struct edd_packet packet;
1136 packet.count = blks;
1137 packet.offset = VTOPOFF(dest);
1138 packet.seg = VTOPSEG(dest);
1140 v86.ctl = V86_FLAGS;
1143 /* Should we Write with verify ?? 0x4302 ? */
1147 v86.edx = od->od_unit;
1148 v86.ds = VTOPSEG(&packet);
1149 v86.esi = VTOPOFF(&packet);
1151 return (v86.efl & 0x1);
1155 bd_chs_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write)
1157 u_int x, bpc, cyl, hd, sec;
1159 bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */
1161 cyl = x / bpc; /* block # / blocks per cylinder */
1162 x %= bpc; /* block offset into cylinder */
1163 hd = x / od->od_sec; /* offset / blocks per track */
1164 sec = x % od->od_sec; /* offset into track */
1166 /* correct sector number for 1-based BIOS numbering */
1170 /* CHS doesn't support cylinders > 1023. */
1173 v86.ctl = V86_FLAGS;
1176 v86.eax = 0x300 | blks;
1178 v86.eax = 0x200 | blks;
1179 v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
1180 v86.edx = (hd << 8) | od->od_unit;
1181 v86.es = VTOPSEG(dest);
1182 v86.ebx = VTOPOFF(dest);
1184 return (v86.efl & 0x1);
1188 bd_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write)
1190 u_int x, sec, result, resid, retry, maxfer;
1191 caddr_t p, xp, bbuf, breg;
1193 /* Just in case some idiot actually tries to read/write -1 blocks... */
1200 /* Decide whether we have to bounce */
1201 if (VTOP(dest) >> 20 != 0 || ((od->od_unit < 0x80) &&
1202 ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16)))) {
1205 * There is a 64k physical boundary somewhere in the
1206 * destination buffer, or the destination buffer is above
1207 * first 1MB of physical memory so we have to arrange a
1208 * suitable bounce buffer. Allocate a buffer twice as large
1209 * as we need to. Use the bottom half unless there is a break
1210 * there, in which case we use the top half.
1212 x = min(FLOPPY_BOUNCEBUF, (unsigned)blks);
1213 bbuf = alloca(x * 2 * BIOSDISK_SECSIZE);
1214 if (((u_int32_t)VTOP(bbuf) & 0xffff0000) ==
1215 ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) {
1218 breg = bbuf + x * BIOSDISK_SECSIZE;
1220 maxfer = x; /* limit transfers to bounce region size */
1228 * Play it safe and don't cross track boundaries.
1229 * (XXX this is probably unnecessary)
1231 sec = dblk % od->od_sec; /* offset into track */
1232 x = min(od->od_sec - sec, resid);
1234 x = min(x, maxfer); /* fit bounce buffer */
1236 /* where do we transfer to? */
1237 xp = bbuf == NULL ? p : breg;
1240 * Put your Data In, Put your Data out,
1241 * Put your Data In, and shake it all about
1243 if (write && bbuf != NULL)
1244 bcopy(p, breg, x * BIOSDISK_SECSIZE);
1247 * Loop retrying the operation a couple of times. The BIOS
1250 for (retry = 0; retry < 3; retry++) {
1251 /* if retrying, reset the drive */
1253 v86.ctl = V86_FLAGS;
1256 v86.edx = od->od_unit;
1260 if (od->od_flags & BD_MODEEDD1)
1261 result = bd_edd_io(od, dblk, x, xp, write);
1263 result = bd_chs_io(od, dblk, x, xp, write);
1269 DEBUG("Write %d sector(s) from %p (0x%x) to %lld %s", x,
1270 p, VTOP(p), dblk, result ? "failed" : "ok");
1272 DEBUG("Read %d sector(s) from %lld to %p (0x%x) %s", x,
1273 dblk, p, VTOP(p), result ? "failed" : "ok");
1277 if (!write && bbuf != NULL)
1278 bcopy(breg, p, x * BIOSDISK_SECSIZE);
1279 p += (x * BIOSDISK_SECSIZE);
1284 /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */
1289 bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1292 return (bd_io(od, dblk, blks, dest, 0));
1296 bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest)
1299 return (bd_io(od, dblk, blks, dest, 1));
1303 bd_getgeom(struct open_disk *od)
1306 v86.ctl = V86_FLAGS;
1309 v86.edx = od->od_unit;
1312 if ((v86.efl & 0x1) || /* carry set */
1313 ((v86.edx & 0xff) <= (unsigned)(od->od_unit & 0x7f))) /* unit # bad */
1316 /* convert max cyl # -> # of cylinders */
1317 od->od_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1;
1318 /* convert max head # -> # of heads */
1319 od->od_hds = ((v86.edx & 0xff00) >> 8) + 1;
1320 od->od_sec = v86.ecx & 0x3f;
1322 DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec);
1327 * Return the BIOS geometry of a given "fixed drive" in a format
1328 * suitable for the legacy bootinfo structure. Since the kernel is
1329 * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we
1330 * prefer to get the information directly, rather than rely on being
1331 * able to put it together from information already maintained for
1332 * different purposes and for a probably different number of drives.
1334 * For valid drives, the geometry is expected in the format (31..0)
1335 * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are
1336 * indicated by returning the geometry of a "1.2M" PC-format floppy
1337 * disk. And, incidentally, what is returned is not the geometry as
1338 * such but the highest valid cylinder, head, and sector numbers.
1341 bd_getbigeom(int bunit)
1344 v86.ctl = V86_FLAGS;
1347 v86.edx = 0x80 + bunit;
1351 return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
1352 (v86.edx & 0xff00) | (v86.ecx & 0x3f);
1356 * Return a suitable dev_t value for (dev).
1358 * In the case where it looks like (dev) is a SCSI disk, we allow the number of
1359 * IDE disks to be specified in $num_ide_disks. There should be a Better Way.
1362 bd_getdev(struct i386_devdesc *dev)
1364 struct open_disk *od;
1369 int unitofs = 0, i, unit;
1371 biosdev = bd_unit2bios(dev->d_unit);
1372 DEBUG("unit %d BIOS device %d", dev->d_unit, biosdev);
1373 if (biosdev == -1) /* not a BIOS device */
1375 if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */
1378 if (biosdev < 0x80) {
1379 /* floppy (or emulated floppy) or ATAPI device */
1380 if (bdinfo[dev->d_unit].bd_type == DT_ATAPI) {
1381 /* is an ATAPI disk */
1384 /* is a floppy disk */
1389 if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) {
1390 /* label OK, disk labelled as SCSI */
1392 /* check for unit number correction hint, now deprecated */
1393 if ((nip = getenv("num_ide_disks")) != NULL) {
1394 i = strtol(nip, &cp, 0);
1395 /* check for parse error */
1396 if ((cp != nip) && (*cp == 0))
1400 /* assume an IDE disk */
1404 /* default root disk unit number */
1405 unit = (biosdev & 0x7f) - unitofs;
1407 /* XXX a better kludge to set the root disk unit number */
1408 if ((nip = getenv("root_disk_unit")) != NULL) {
1409 i = strtol(nip, &cp, 0);
1410 /* check for parse error */
1411 if ((cp != nip) && (*cp == 0))
1415 rootdev = MAKEBOOTDEV(major, dev->d_kind.biosdisk.slice + 1, unit,
1416 dev->d_kind.biosdisk.partition);
1417 DEBUG("dev is 0x%x\n", rootdev);