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freebsd-dev/stand/i386/libi386/biosdisk.c
Colin Percival 313724bab9 loader: Use tslog to instrument some functions 
In my initial testing, these are the functions which showed up as
being worth instrumenting.  More may be added later.

common/console.c: cons_probe
common/gfx_fb.c: read_list, insert_font, autoload_font
common/interp.c: interact
common/interp_lua.c: interp_init, interp_run
efi/libefi/efipart.c: efipart_readwrite
i386/libi386/biosdisk.c: bd_init, bd_open, bd_edd_io, bd_chs_io, bd_io
libsa/open.c: open
libsa/read.c: read
libsa/twiddle.c: twiddle

Note that profiling interp_run may be of questionable utility as it
may depend on user behaviour (e.g. pressing keys).

Reviewed by:	kevans (earlier version)
2021-06-20 20:09:48 -07:00

1399 lines
32 KiB
C
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/*-
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* Copyright (c) 2012 Andrey V. Elsukov <ae@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* BIOS disk device handling.
*
* Ideas and algorithms from:
*
* - NetBSD libi386/biosdisk.c
* - FreeBSD biosboot/disk.c
*
*/
#include <sys/disk.h>
#include <sys/limits.h>
#include <sys/queue.h>
#include <stand.h>
#include <machine/bootinfo.h>
#include <stdarg.h>
#include <stdbool.h>
#include <bootstrap.h>
#include <btxv86.h>
#include <edd.h>
#include "disk.h"
#include "libi386.h"
#define BIOS_NUMDRIVES 0x475
#define BIOSDISK_SECSIZE 512
#define BUFSIZE (1 * BIOSDISK_SECSIZE)
#define DT_ATAPI 0x10 /* disk type for ATAPI floppies */
#define WDMAJOR 0 /* major numbers for devices we frontend for */
#define WFDMAJOR 1
#define FDMAJOR 2
#define DAMAJOR 4
#define ACDMAJOR 117
#define CDMAJOR 15
/*
* INT13 commands
*/
#define CMD_RESET 0x0000
#define CMD_READ_CHS 0x0200
#define CMD_WRITE_CHS 0x0300
#define CMD_READ_PARAM 0x0800
#define CMD_DRIVE_TYPE 0x1500
#define CMD_CHECK_EDD 0x4100
#define CMD_READ_LBA 0x4200
#define CMD_WRITE_LBA 0x4300
#define CMD_EXT_PARAM 0x4800
#define CMD_CD_GET_STATUS 0x4b01
#define DISK_BIOS 0x13
#ifdef DISK_DEBUG
#define DPRINTF(fmt, args...) printf("%s: " fmt "\n", __func__, ## args)
#else
#define DPRINTF(fmt, args...) ((void)0)
#endif
struct specification_packet {
uint8_t sp_size;
uint8_t sp_bootmedia;
uint8_t sp_drive;
uint8_t sp_controller;
uint32_t sp_lba;
uint16_t sp_devicespec;
uint16_t sp_buffersegment;
uint16_t sp_loadsegment;
uint16_t sp_sectorcount;
uint16_t sp_cylsec;
uint8_t sp_head;
uint8_t sp_dummy[16]; /* Avoid memory corruption */
};
/*
* List of BIOS devices, translation from disk unit number to
* BIOS unit number.
*/
typedef struct bdinfo
{
STAILQ_ENTRY(bdinfo) bd_link; /* link in device list */
int bd_unit; /* BIOS unit number */
int bd_cyl; /* BIOS geometry */
int bd_hds;
int bd_sec;
int bd_flags;
#define BD_MODEINT13 0x0000
#define BD_MODEEDD1 0x0001
#define BD_MODEEDD3 0x0002
#define BD_MODEEDD (BD_MODEEDD1 | BD_MODEEDD3)
#define BD_MODEMASK 0x0003
#define BD_FLOPPY 0x0004
#define BD_CDROM 0x0008
#define BD_NO_MEDIA 0x0010
int bd_type; /* BIOS 'drive type' (floppy only) */
uint16_t bd_sectorsize; /* Sector size */
uint64_t bd_sectors; /* Disk size */
int bd_open; /* reference counter */
void *bd_bcache; /* buffer cache data */
} bdinfo_t;
#define BD_RD 0
#define BD_WR 1
typedef STAILQ_HEAD(bdinfo_list, bdinfo) bdinfo_list_t;
static bdinfo_list_t fdinfo = STAILQ_HEAD_INITIALIZER(fdinfo);
static bdinfo_list_t cdinfo = STAILQ_HEAD_INITIALIZER(cdinfo);
static bdinfo_list_t hdinfo = STAILQ_HEAD_INITIALIZER(hdinfo);
static void bd_io_workaround(bdinfo_t *);
static int bd_io(struct disk_devdesc *, bdinfo_t *, daddr_t, int, caddr_t, int);
static bool bd_int13probe(bdinfo_t *);
static int bd_init(void);
static int cd_init(void);
static int fd_init(void);
static int bd_strategy(void *devdata, int flag, daddr_t dblk, size_t size,
char *buf, size_t *rsize);
static int bd_realstrategy(void *devdata, int flag, daddr_t dblk, size_t size,
char *buf, size_t *rsize);
static int bd_open(struct open_file *f, ...);
static int bd_close(struct open_file *f);
static int bd_ioctl(struct open_file *f, u_long cmd, void *data);
static int bd_print(int verbose);
static int cd_print(int verbose);
static int fd_print(int verbose);
static void bd_reset_disk(int);
static int bd_get_diskinfo_std(struct bdinfo *);
struct devsw biosfd = {
.dv_name = "fd",
.dv_type = DEVT_FD,
.dv_init = fd_init,
.dv_strategy = bd_strategy,
.dv_open = bd_open,
.dv_close = bd_close,
.dv_ioctl = bd_ioctl,
.dv_print = fd_print,
.dv_cleanup = NULL
};
struct devsw bioscd = {
.dv_name = "cd",
.dv_type = DEVT_CD,
.dv_init = cd_init,
.dv_strategy = bd_strategy,
.dv_open = bd_open,
.dv_close = bd_close,
.dv_ioctl = bd_ioctl,
.dv_print = cd_print,
.dv_cleanup = NULL
};
struct devsw bioshd = {
.dv_name = "disk",
.dv_type = DEVT_DISK,
.dv_init = bd_init,
.dv_strategy = bd_strategy,
.dv_open = bd_open,
.dv_close = bd_close,
.dv_ioctl = bd_ioctl,
.dv_print = bd_print,
.dv_cleanup = NULL
};
static bdinfo_list_t *
bd_get_bdinfo_list(struct devsw *dev)
{
if (dev->dv_type == DEVT_DISK)
return (&hdinfo);
if (dev->dv_type == DEVT_CD)
return (&cdinfo);
if (dev->dv_type == DEVT_FD)
return (&fdinfo);
return (NULL);
}
/* XXX this gets called way way too often, investigate */
static bdinfo_t *
bd_get_bdinfo(struct devdesc *dev)
{
bdinfo_list_t *bdi;
bdinfo_t *bd = NULL;
int unit;
bdi = bd_get_bdinfo_list(dev->d_dev);
if (bdi == NULL)
return (bd);
unit = 0;
STAILQ_FOREACH(bd, bdi, bd_link) {
if (unit == dev->d_unit)
return (bd);
unit++;
}
return (bd);
}
/*
* Translate between BIOS device numbers and our private unit numbers.
*/
int
bd_bios2unit(int biosdev)
{
bdinfo_list_t *bdi[] = { &fdinfo, &cdinfo, &hdinfo, NULL };
bdinfo_t *bd;
int i, unit;
DPRINTF("looking for bios device 0x%x", biosdev);
for (i = 0; bdi[i] != NULL; i++) {
unit = 0;
STAILQ_FOREACH(bd, bdi[i], bd_link) {
if (bd->bd_unit == biosdev) {
DPRINTF("bd unit %d is BIOS device 0x%x", unit,
bd->bd_unit);
return (unit);
}
unit++;
}
}
return (-1);
}
int
bd_unit2bios(struct i386_devdesc *dev)
{
bdinfo_list_t *bdi;
bdinfo_t *bd;
int unit;
bdi = bd_get_bdinfo_list(dev->dd.d_dev);
if (bdi == NULL)
return (-1);
unit = 0;
STAILQ_FOREACH(bd, bdi, bd_link) {
if (unit == dev->dd.d_unit)
return (bd->bd_unit);
unit++;
}
return (-1);
}
/*
* Use INT13 AH=15 - Read Drive Type.
*/
static int
fd_count(void)
{
int drive;
for (drive = 0; drive < MAXBDDEV; drive++) {
bd_reset_disk(drive);
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
v86.eax = CMD_DRIVE_TYPE;
v86.edx = drive;
v86int();
if (V86_CY(v86.efl))
break;
if ((v86.eax & 0x300) == 0)
break;
}
return (drive);
}
/*
* Quiz the BIOS for disk devices, save a little info about them.
*/
static int
fd_init(void)
{
int unit, numfd;
bdinfo_t *bd;
numfd = fd_count();
for (unit = 0; unit < numfd; unit++) {
if ((bd = calloc(1, sizeof(*bd))) == NULL)
break;
bd->bd_sectorsize = BIOSDISK_SECSIZE;
bd->bd_flags = BD_FLOPPY;
bd->bd_unit = unit;
/* Use std diskinfo for floppy drive */
if (bd_get_diskinfo_std(bd) != 0) {
free(bd);
break;
}
if (bd->bd_sectors == 0)
bd->bd_flags |= BD_NO_MEDIA;
printf("BIOS drive %c: is %s%d\n", ('A' + unit),
biosfd.dv_name, unit);
STAILQ_INSERT_TAIL(&fdinfo, bd, bd_link);
}
bcache_add_dev(unit);
return (0);
}
static int
bd_init(void)
{
int base, unit;
bdinfo_t *bd;
TSENTER();
base = 0x80;
for (unit = 0; unit < *(unsigned char *)PTOV(BIOS_NUMDRIVES); unit++) {
/*
* Check the BIOS equipment list for number of fixed disks.
*/
if ((bd = calloc(1, sizeof(*bd))) == NULL)
break;
bd->bd_unit = base + unit;
if (!bd_int13probe(bd)) {
free(bd);
break;
}
printf("BIOS drive %c: is %s%d\n", ('C' + unit),
bioshd.dv_name, unit);
STAILQ_INSERT_TAIL(&hdinfo, bd, bd_link);
}
bcache_add_dev(unit);
TSEXIT();
return (0);
}
/*
* We can't quiz, we have to be told what device to use, so this function
* doesn't do anything. Instead, the loader calls bc_add() with the BIOS
* device number to add.
*/
static int
cd_init(void)
{
return (0);
}
/*
* Information from bootable CD-ROM.
*/
static int
bd_get_diskinfo_cd(struct bdinfo *bd)
{
struct specification_packet bc_sp;
int ret = -1;
(void) memset(&bc_sp, 0, sizeof (bc_sp));
/* Set sp_size as per specification. */
bc_sp.sp_size = sizeof (bc_sp) - sizeof (bc_sp.sp_dummy);
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
v86.eax = CMD_CD_GET_STATUS;
v86.edx = bd->bd_unit;
v86.ds = VTOPSEG(&bc_sp);
v86.esi = VTOPOFF(&bc_sp);
v86int();
if ((v86.eax & 0xff00) == 0 &&
bc_sp.sp_drive == bd->bd_unit) {
bd->bd_cyl = ((bc_sp.sp_cylsec & 0xc0) << 2) +
((bc_sp.sp_cylsec & 0xff00) >> 8) + 1;
bd->bd_sec = bc_sp.sp_cylsec & 0x3f;
bd->bd_hds = bc_sp.sp_head + 1;
bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec;
if (bc_sp.sp_bootmedia & 0x0F) {
/* Floppy or hard-disk emulation */
bd->bd_sectorsize = BIOSDISK_SECSIZE;
return (-1);
} else {
bd->bd_sectorsize = 2048;
bd->bd_flags = BD_MODEEDD | BD_CDROM;
ret = 0;
}
}
/*
* If this is the boot_drive, default to non-emulation bootable CD-ROM.
*/
if (ret != 0 && bd->bd_unit >= 0x88) {
bd->bd_cyl = 0;
bd->bd_hds = 1;
bd->bd_sec = 15;
bd->bd_sectorsize = 2048;
bd->bd_flags = BD_MODEEDD | BD_CDROM;
bd->bd_sectors = 0;
ret = 0;
}
/*
* Note we can not use bd_get_diskinfo_ext() nor bd_get_diskinfo_std()
* here - some systems do get hung with those.
*/
/*
* Still no size? use 7.961GB. The size does not really matter
* as long as it is reasonably large to make our reads to pass
* the sector count check.
*/
if (bd->bd_sectors == 0)
bd->bd_sectors = 4173824;
return (ret);
}
int
bc_add(int biosdev)
{
bdinfo_t *bd;
int nbcinfo = 0;
if (!STAILQ_EMPTY(&cdinfo))
return (-1);
if ((bd = calloc(1, sizeof(*bd))) == NULL)
return (-1);
bd->bd_unit = biosdev;
if (bd_get_diskinfo_cd(bd) < 0) {
free(bd);
return (-1);
}
STAILQ_INSERT_TAIL(&cdinfo, bd, bd_link);
printf("BIOS CD is cd%d\n", nbcinfo);
nbcinfo++;
bcache_add_dev(nbcinfo); /* register cd device in bcache */
return(0);
}
/*
* Return EDD version or 0 if EDD is not supported on this drive.
*/
static int
bd_check_extensions(int unit)
{
/* do not use ext calls for floppy devices */
if (unit < 0x80)
return (0);
/* Determine if we can use EDD with this device. */
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
v86.eax = CMD_CHECK_EDD;
v86.edx = unit;
v86.ebx = EDD_QUERY_MAGIC;
v86int();
if (V86_CY(v86.efl) || /* carry set */
(v86.ebx & 0xffff) != EDD_INSTALLED) /* signature */
return (0);
/* extended disk access functions (AH=42h-44h,47h,48h) supported */
if ((v86.ecx & EDD_INTERFACE_FIXED_DISK) == 0)
return (0);
return ((v86.eax >> 8) & 0xff);
}
static void
bd_reset_disk(int unit)
{
/* reset disk */
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
v86.eax = CMD_RESET;
v86.edx = unit;
v86int();
}
/*
* Read CHS info. Return 0 on success, error otherwise.
*/
static int
bd_get_diskinfo_std(struct bdinfo *bd)
{
bzero(&v86, sizeof(v86));
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
v86.eax = CMD_READ_PARAM;
v86.edx = bd->bd_unit;
v86int();
if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0))
return ((v86.eax & 0xff00) >> 8);
/* return custom error on absurd sector number */
if ((v86.ecx & 0x3f) == 0)
return (0x60);
bd->bd_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1;
/* Convert max head # -> # of heads */
bd->bd_hds = ((v86.edx & 0xff00) >> 8) + 1;
bd->bd_sec = v86.ecx & 0x3f;
bd->bd_type = v86.ebx;
bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec;
return (0);
}
/*
* Read EDD info. Return 0 on success, error otherwise.
*
* Avoid stack corruption on some systems by adding extra bytes to
* params block.
*/
static int
bd_get_diskinfo_ext(struct bdinfo *bd)
{
struct disk_params {
struct edd_params head;
struct edd_device_path_v3 device_path;
uint8_t dummy[16];
} __packed dparams;
struct edd_params *params;
uint64_t total;
params = &dparams.head;
/* Get disk params */
bzero(&dparams, sizeof(dparams));
params->len = sizeof(struct edd_params_v3);
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
v86.eax = CMD_EXT_PARAM;
v86.edx = bd->bd_unit;
v86.ds = VTOPSEG(&dparams);
v86.esi = VTOPOFF(&dparams);
v86int();
if (V86_CY(v86.efl) && ((v86.eax & 0xff00) != 0))
return ((v86.eax & 0xff00) >> 8);
/*
* Sector size must be a multiple of 512 bytes.
* An alternate test would be to check power of 2,
* powerof2(params.sector_size).
* 16K is largest read buffer we can use at this time.
*/
if (params->sector_size >= 512 &&
params->sector_size <= 16384 &&
(params->sector_size % BIOSDISK_SECSIZE) == 0)
bd->bd_sectorsize = params->sector_size;
bd->bd_cyl = params->cylinders;
bd->bd_hds = params->heads;
bd->bd_sec = params->sectors_per_track;
if (params->sectors != 0) {
total = params->sectors;
} else {
total = (uint64_t)params->cylinders *
params->heads * params->sectors_per_track;
}
bd->bd_sectors = total;
return (0);
}
/*
* Try to detect a device supported by the legacy int13 BIOS
*/
static bool
bd_int13probe(bdinfo_t *bd)
{
int edd, ret;
bd->bd_flags &= ~BD_NO_MEDIA;
if ((bd->bd_flags & BD_CDROM) != 0) {
return (bd_get_diskinfo_cd(bd) == 0);
}
edd = bd_check_extensions(bd->bd_unit);
if (edd == 0)
bd->bd_flags |= BD_MODEINT13;
else if (edd < 0x30)
bd->bd_flags |= BD_MODEEDD1;
else
bd->bd_flags |= BD_MODEEDD3;
/* Default sector size */
if (bd->bd_sectorsize == 0)
bd->bd_sectorsize = BIOSDISK_SECSIZE;
/*
* Test if the floppy device is present, so we can avoid receiving
* bogus information from bd_get_diskinfo_std().
*/
if (bd->bd_unit < 0x80) {
/* reset disk */
bd_reset_disk(bd->bd_unit);
/* Get disk type */
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
v86.eax = CMD_DRIVE_TYPE;
v86.edx = bd->bd_unit;
v86int();
if (V86_CY(v86.efl) || (v86.eax & 0x300) == 0)
return (false);
}
ret = 1;
if (edd != 0)
ret = bd_get_diskinfo_ext(bd);
if (ret != 0 || bd->bd_sectors == 0)
ret = bd_get_diskinfo_std(bd);
if (ret != 0 && bd->bd_unit < 0x80) {
/* Set defaults for 1.44 floppy */
bd->bd_cyl = 80;
bd->bd_hds = 2;
bd->bd_sec = 18;
bd->bd_sectors = 2880;
/* Since we are there, there most likely is no media */
bd->bd_flags |= BD_NO_MEDIA;
ret = 0;
}
if (ret != 0) {
if (bd->bd_sectors != 0 && edd != 0) {
bd->bd_sec = 63;
bd->bd_hds = 255;
bd->bd_cyl =
(bd->bd_sectors + bd->bd_sec * bd->bd_hds - 1) /
bd->bd_sec * bd->bd_hds;
} else {
const char *dv_name;
if ((bd->bd_flags & BD_FLOPPY) != 0)
dv_name = biosfd.dv_name;
else
dv_name = bioshd.dv_name;
printf("Can not get information about %s unit %#x\n",
dv_name, bd->bd_unit);
return (false);
}
}
if (bd->bd_sec == 0)
bd->bd_sec = 63;
if (bd->bd_hds == 0)
bd->bd_hds = 255;
if (bd->bd_sectors == 0)
bd->bd_sectors = (uint64_t)bd->bd_cyl * bd->bd_hds * bd->bd_sec;
DPRINTF("unit 0x%x geometry %d/%d/%d\n", bd->bd_unit, bd->bd_cyl,
bd->bd_hds, bd->bd_sec);
return (true);
}
static int
bd_count(bdinfo_list_t *bdi)
{
bdinfo_t *bd;
int i;
i = 0;
STAILQ_FOREACH(bd, bdi, bd_link)
i++;
return (i);
}
/*
* Print information about disks
*/
static int
bd_print_common(struct devsw *dev, bdinfo_list_t *bdi, int verbose)
{
char line[80];
struct disk_devdesc devd;
bdinfo_t *bd;
int i, ret = 0;
char drive;
if (STAILQ_EMPTY(bdi))
return (0);
printf("%s devices:", dev->dv_name);
if ((ret = pager_output("\n")) != 0)
return (ret);
i = -1;
STAILQ_FOREACH(bd, bdi, bd_link) {
i++;
switch (dev->dv_type) {
case DEVT_FD:
drive = 'A';
break;
case DEVT_CD:
drive = 'C' + bd_count(&hdinfo);
break;
default:
drive = 'C';
break;
}
snprintf(line, sizeof(line),
" %s%d: BIOS drive %c (%s%ju X %u):\n",
dev->dv_name, i, drive + i,
(bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA ?
"no media, " : "",
(uintmax_t)bd->bd_sectors,
bd->bd_sectorsize);
if ((ret = pager_output(line)) != 0)
break;
if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA)
continue;
if (dev->dv_type != DEVT_DISK)
continue;
devd.dd.d_dev = dev;
devd.dd.d_unit = i;
devd.d_slice = D_SLICENONE;
devd.d_partition = D_PARTNONE;
if (disk_open(&devd,
bd->bd_sectorsize * bd->bd_sectors,
bd->bd_sectorsize) == 0) {
snprintf(line, sizeof(line), " %s%d",
dev->dv_name, i);
ret = disk_print(&devd, line, verbose);
disk_close(&devd);
if (ret != 0)
break;
}
}
return (ret);
}
static int
fd_print(int verbose)
{
return (bd_print_common(&biosfd, &fdinfo, verbose));
}
static int
bd_print(int verbose)
{
return (bd_print_common(&bioshd, &hdinfo, verbose));
}
static int
cd_print(int verbose)
{
return (bd_print_common(&bioscd, &cdinfo, verbose));
}
/*
* Read disk size from partition.
* This is needed to work around buggy BIOS systems returning
* wrong (truncated) disk media size.
* During bd_probe() we tested if the multiplication of bd_sectors
* would overflow so it should be safe to perform here.
*/
static uint64_t
bd_disk_get_sectors(struct disk_devdesc *dev)
{
bdinfo_t *bd;
struct disk_devdesc disk;
uint64_t size;
bd = bd_get_bdinfo(&dev->dd);
if (bd == NULL)
return (0);
disk.dd.d_dev = dev->dd.d_dev;
disk.dd.d_unit = dev->dd.d_unit;
disk.d_slice = D_SLICENONE;
disk.d_partition = D_PARTNONE;
disk.d_offset = 0;
size = bd->bd_sectors * bd->bd_sectorsize;
if (disk_open(&disk, size, bd->bd_sectorsize) == 0) {
(void) disk_ioctl(&disk, DIOCGMEDIASIZE, &size);
disk_close(&disk);
}
return (size / bd->bd_sectorsize);
}
/*
* Attempt to open the disk described by (dev) for use by (f).
*
* Note that the philosophy here is "give them exactly what
* they ask for". This is necessary because being too "smart"
* about what the user might want leads to complications.
* (eg. given no slice or partition value, with a disk that is
* sliced - are they after the first BSD slice, or the DOS
* slice before it?)
*/
static int
bd_open(struct open_file *f, ...)
{
bdinfo_t *bd;
struct disk_devdesc *dev;
va_list ap;
int rc;
TSENTER();
va_start(ap, f);
dev = va_arg(ap, struct disk_devdesc *);
va_end(ap);
bd = bd_get_bdinfo(&dev->dd);
if (bd == NULL)
return (EIO);
if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA) {
if (!bd_int13probe(bd))
return (EIO);
if ((bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA)
return (EIO);
}
if (bd->bd_bcache == NULL)
bd->bd_bcache = bcache_allocate();
if (bd->bd_open == 0)
bd->bd_sectors = bd_disk_get_sectors(dev);
bd->bd_open++;
rc = 0;
if (dev->dd.d_dev->dv_type == DEVT_DISK) {
rc = disk_open(dev, bd->bd_sectors * bd->bd_sectorsize,
bd->bd_sectorsize);
if (rc != 0) {
bd->bd_open--;
if (bd->bd_open == 0) {
bcache_free(bd->bd_bcache);
bd->bd_bcache = NULL;
}
}
}
TSEXIT();
return (rc);
}
static int
bd_close(struct open_file *f)
{
struct disk_devdesc *dev;
bdinfo_t *bd;
int rc = 0;
dev = (struct disk_devdesc *)f->f_devdata;
bd = bd_get_bdinfo(&dev->dd);
if (bd == NULL)
return (EIO);
bd->bd_open--;
if (bd->bd_open == 0) {
bcache_free(bd->bd_bcache);
bd->bd_bcache = NULL;
}
if (dev->dd.d_dev->dv_type == DEVT_DISK)
rc = disk_close(dev);
return (rc);
}
static int
bd_ioctl(struct open_file *f, u_long cmd, void *data)
{
bdinfo_t *bd;
struct disk_devdesc *dev;
int rc;
dev = (struct disk_devdesc *)f->f_devdata;
bd = bd_get_bdinfo(&dev->dd);
if (bd == NULL)
return (EIO);
if (dev->dd.d_dev->dv_type == DEVT_DISK) {
rc = disk_ioctl(dev, cmd, data);
if (rc != ENOTTY)
return (rc);
}
switch (cmd) {
case DIOCGSECTORSIZE:
*(uint32_t *)data = bd->bd_sectorsize;
break;
case DIOCGMEDIASIZE:
*(uint64_t *)data = bd->bd_sectors * bd->bd_sectorsize;
break;
default:
return (ENOTTY);
}
return (0);
}
static int
bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size,
char *buf, size_t *rsize)
{
bdinfo_t *bd;
struct bcache_devdata bcd;
struct disk_devdesc *dev;
daddr_t offset;
dev = (struct disk_devdesc *)devdata;
bd = bd_get_bdinfo(&dev->dd);
if (bd == NULL)
return (EINVAL);
bcd.dv_strategy = bd_realstrategy;
bcd.dv_devdata = devdata;
bcd.dv_cache = bd->bd_bcache;
offset = 0;
if (dev->dd.d_dev->dv_type == DEVT_DISK) {
offset = dev->d_offset * bd->bd_sectorsize;
offset /= BIOSDISK_SECSIZE;
}
return (bcache_strategy(&bcd, rw, dblk + offset, size,
buf, rsize));
}
static int
bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size,
char *buf, size_t *rsize)
{
struct disk_devdesc *dev = (struct disk_devdesc *)devdata;
bdinfo_t *bd;
uint64_t disk_blocks, offset, d_offset;
size_t blks, blkoff, bsize, bio_size, rest;
caddr_t bbuf = NULL;
int rc;
bd = bd_get_bdinfo(&dev->dd);
if (bd == NULL || (bd->bd_flags & BD_NO_MEDIA) == BD_NO_MEDIA)
return (EIO);
/*
* First make sure the IO size is a multiple of 512 bytes. While we do
* process partial reads below, the strategy mechanism is built
* assuming IO is a multiple of 512B blocks. If the request is not
* a multiple of 512B blocks, it has to be some sort of bug.
*/
if (size == 0 || (size % BIOSDISK_SECSIZE) != 0) {
printf("bd_strategy: %d bytes I/O not multiple of %d\n",
size, BIOSDISK_SECSIZE);
return (EIO);
}
DPRINTF("open_disk %p", dev);
offset = dblk * BIOSDISK_SECSIZE;
dblk = offset / bd->bd_sectorsize;
blkoff = offset % bd->bd_sectorsize;
/*
* Check the value of the size argument. We do have quite small
* heap (64MB), but we do not know good upper limit, so we check against
* INT_MAX here. This will also protect us against possible overflows
* while translating block count to bytes.
*/
if (size > INT_MAX) {
DPRINTF("too large I/O: %zu bytes", size);
return (EIO);
}
blks = size / bd->bd_sectorsize;
if (blks == 0 || (size % bd->bd_sectorsize) != 0)
blks++;
if (dblk > dblk + blks)
return (EIO);
if (rsize)
*rsize = 0;
/*
* Get disk blocks, this value is either for whole disk or for
* partition.
*/
d_offset = 0;
disk_blocks = 0;
if (dev->dd.d_dev->dv_type == DEVT_DISK) {
if (disk_ioctl(dev, DIOCGMEDIASIZE, &disk_blocks) == 0) {
/* DIOCGMEDIASIZE does return bytes. */
disk_blocks /= bd->bd_sectorsize;
}
d_offset = dev->d_offset;
}
if (disk_blocks == 0)
disk_blocks = bd->bd_sectors - d_offset;
/* Validate source block address. */
if (dblk < d_offset || dblk >= d_offset + disk_blocks)
return (EIO);
/*
* Truncate if we are crossing disk or partition end.
*/
if (dblk + blks >= d_offset + disk_blocks) {
blks = d_offset + disk_blocks - dblk;
size = blks * bd->bd_sectorsize;
DPRINTF("short I/O %d", blks);
}
bio_size = min(BIO_BUFFER_SIZE, size);
while (bio_size > bd->bd_sectorsize) {
bbuf = bio_alloc(bio_size);
if (bbuf != NULL)
break;
bio_size -= bd->bd_sectorsize;
}
if (bbuf == NULL) {
bio_size = V86_IO_BUFFER_SIZE;
if (bio_size / bd->bd_sectorsize == 0)
panic("BUG: Real mode buffer is too small");
/* Use alternate 4k buffer */
bbuf = PTOV(V86_IO_BUFFER);
}
rest = size;
rc = 0;
while (blks > 0) {
int x = min(blks, bio_size / bd->bd_sectorsize);
switch (rw & F_MASK) {
case F_READ:
DPRINTF("read %d from %lld to %p", x, dblk, buf);
bsize = bd->bd_sectorsize * x - blkoff;
if (rest < bsize)
bsize = rest;
if ((rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD)) != 0) {
rc = EIO;
goto error;
}
bcopy(bbuf + blkoff, buf, bsize);
break;
case F_WRITE :
DPRINTF("write %d from %lld to %p", x, dblk, buf);
if (blkoff != 0) {
/*
* We got offset to sector, read 1 sector to
* bbuf.
*/
x = 1;
bsize = bd->bd_sectorsize - blkoff;
bsize = min(bsize, rest);
rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD);
} else if (rest < bd->bd_sectorsize) {
/*
* The remaining block is not full
* sector. Read 1 sector to bbuf.
*/
x = 1;
bsize = rest;
rc = bd_io(dev, bd, dblk, x, bbuf, BD_RD);
} else {
/* We can write full sector(s). */
bsize = bd->bd_sectorsize * x;
}
/*
* Put your Data In, Put your Data out,
* Put your Data In, and shake it all about
*/
bcopy(buf, bbuf + blkoff, bsize);
if ((rc = bd_io(dev, bd, dblk, x, bbuf, BD_WR)) != 0) {
rc = EIO;
goto error;
}
break;
default:
/* DO NOTHING */
rc = EROFS;
goto error;
}
blkoff = 0;
buf += bsize;
rest -= bsize;
blks -= x;
dblk += x;
}
if (rsize != NULL)
*rsize = size;
error:
if (bbuf != PTOV(V86_IO_BUFFER))
bio_free(bbuf, bio_size);
return (rc);
}
static int
bd_edd_io(bdinfo_t *bd, daddr_t dblk, int blks, caddr_t dest,
int dowrite)
{
static struct edd_packet packet;
TSENTER();
packet.len = sizeof(struct edd_packet);
packet.count = blks;
packet.off = VTOPOFF(dest);
packet.seg = VTOPSEG(dest);
packet.lba = dblk;
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
if (dowrite == BD_WR)
v86.eax = CMD_WRITE_LBA; /* maybe Write with verify 0x4302? */
else
v86.eax = CMD_READ_LBA;
v86.edx = bd->bd_unit;
v86.ds = VTOPSEG(&packet);
v86.esi = VTOPOFF(&packet);
v86int();
if (V86_CY(v86.efl))
return (v86.eax >> 8);
TSEXIT();
return (0);
}
static int
bd_chs_io(bdinfo_t *bd, daddr_t dblk, int blks, caddr_t dest,
int dowrite)
{
uint32_t x, bpc, cyl, hd, sec;
TSENTER();
bpc = bd->bd_sec * bd->bd_hds; /* blocks per cylinder */
x = dblk;
cyl = x / bpc; /* block # / blocks per cylinder */
x %= bpc; /* block offset into cylinder */
hd = x / bd->bd_sec; /* offset / blocks per track */
sec = x % bd->bd_sec; /* offset into track */
/* correct sector number for 1-based BIOS numbering */
sec++;
if (cyl > 1023) {
/* CHS doesn't support cylinders > 1023. */
return (1);
}
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
if (dowrite == BD_WR)
v86.eax = CMD_WRITE_CHS | blks;
else
v86.eax = CMD_READ_CHS | blks;
v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec;
v86.edx = (hd << 8) | bd->bd_unit;
v86.es = VTOPSEG(dest);
v86.ebx = VTOPOFF(dest);
v86int();
if (V86_CY(v86.efl))
return (v86.eax >> 8);
TSEXIT();
return (0);
}
static void
bd_io_workaround(bdinfo_t *bd)
{
uint8_t buf[8 * 1024];
bd_edd_io(bd, 0xffffffff, 1, (caddr_t)buf, BD_RD);
}
static int
bd_io(struct disk_devdesc *dev, bdinfo_t *bd, daddr_t dblk, int blks,
caddr_t dest, int dowrite)
{
int result, retry;
TSENTER();
/* Just in case some idiot actually tries to read/write -1 blocks... */
if (blks < 0)
return (-1);
/*
* Workaround for a problem with some HP ProLiant BIOS failing to work
* out the boot disk after installation. hrs and kuriyama discovered
* this problem with an HP ProLiant DL320e Gen 8 with a 3TB HDD, and
* discovered that an int13h call seems to cause a buffer overrun in
* the bios. The problem is alleviated by doing an extra read before
* the buggy read. It is not immediately known whether other models
* are similarly affected.
* Loop retrying the operation a couple of times. The BIOS
* may also retry.
*/
if (dowrite == BD_RD && dblk >= 0x100000000)
bd_io_workaround(bd);
for (retry = 0; retry < 3; retry++) {
if (bd->bd_flags & BD_MODEEDD)
result = bd_edd_io(bd, dblk, blks, dest, dowrite);
else
result = bd_chs_io(bd, dblk, blks, dest, dowrite);
if (result == 0) {
if (bd->bd_flags & BD_NO_MEDIA)
bd->bd_flags &= ~BD_NO_MEDIA;
break;
}
bd_reset_disk(bd->bd_unit);
/*
* Error codes:
* 20h controller failure
* 31h no media in drive (IBM/MS INT 13 extensions)
* 80h no media in drive, VMWare (Fusion)
* There is no reason to repeat the IO with errors above.
*/
if (result == 0x20 || result == 0x31 || result == 0x80) {
bd->bd_flags |= BD_NO_MEDIA;
break;
}
}
if (result != 0 && (bd->bd_flags & BD_NO_MEDIA) == 0) {
if (dowrite == BD_WR) {
printf("%s%d: Write %d sector(s) from %p (0x%x) "
"to %lld: 0x%x\n", dev->dd.d_dev->dv_name,
dev->dd.d_unit, blks, dest, VTOP(dest), dblk,
result);
} else {
printf("%s%d: Read %d sector(s) from %lld to %p "
"(0x%x): 0x%x\n", dev->dd.d_dev->dv_name,
dev->dd.d_unit, blks, dblk, dest, VTOP(dest),
result);
}
}
TSEXIT();
return (result);
}
/*
* Return the BIOS geometry of a given "fixed drive" in a format
* suitable for the legacy bootinfo structure. Since the kernel is
* expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we
* prefer to get the information directly, rather than rely on being
* able to put it together from information already maintained for
* different purposes and for a probably different number of drives.
*
* For valid drives, the geometry is expected in the format (31..0)
* "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are
* indicated by returning the geometry of a "1.2M" PC-format floppy
* disk. And, incidentally, what is returned is not the geometry as
* such but the highest valid cylinder, head, and sector numbers.
*/
uint32_t
bd_getbigeom(int bunit)
{
v86.ctl = V86_FLAGS;
v86.addr = DISK_BIOS;
v86.eax = CMD_READ_PARAM;
v86.edx = 0x80 + bunit;
v86int();
if (V86_CY(v86.efl))
return (0x4f010f);
return (((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
(v86.edx & 0xff00) | (v86.ecx & 0x3f));
}
/*
* Return a suitable dev_t value for (dev).
*
* In the case where it looks like (dev) is a SCSI disk, we allow the number of
* IDE disks to be specified in $num_ide_disks. There should be a Better Way.
*/
int
bd_getdev(struct i386_devdesc *d)
{
struct disk_devdesc *dev;
bdinfo_t *bd;
int biosdev;
int major;
int rootdev;
char *nip, *cp;
int i, unit, slice, partition;
/* XXX: Assume partition 'a'. */
slice = 0;
partition = 0;
dev = (struct disk_devdesc *)d;
bd = bd_get_bdinfo(&dev->dd);
if (bd == NULL)
return (-1);
biosdev = bd_unit2bios(d);
DPRINTF("unit %d BIOS device %d", dev->dd.d_unit, biosdev);
if (biosdev == -1) /* not a BIOS device */
return (-1);
if (dev->dd.d_dev->dv_type == DEVT_DISK) {
if (disk_open(dev, bd->bd_sectors * bd->bd_sectorsize,
bd->bd_sectorsize) != 0) /* oops, not a viable device */
return (-1);
else
disk_close(dev);
slice = dev->d_slice + 1;
partition = dev->d_partition;
}
if (biosdev < 0x80) {
/* floppy (or emulated floppy) or ATAPI device */
if (bd->bd_type == DT_ATAPI) {
/* is an ATAPI disk */
major = WFDMAJOR;
} else {
/* is a floppy disk */
major = FDMAJOR;
}
} else {
/* assume an IDE disk */
major = WDMAJOR;
}
/* default root disk unit number */
unit = biosdev & 0x7f;
if (dev->dd.d_dev->dv_type == DEVT_CD) {
/*
* XXX: Need to examine device spec here to figure out if
* SCSI or ATAPI. No idea on how to figure out device number.
* All we can really pass to the kernel is what bus and device
* on which bus we were booted from, which dev_t isn't well
* suited to since those number don't match to unit numbers
* very well. We may just need to engage in a hack where
* we pass -C to the boot args if we are the boot device.
*/
major = ACDMAJOR;
unit = 0; /* XXX */
}
/* XXX a better kludge to set the root disk unit number */
if ((nip = getenv("root_disk_unit")) != NULL) {
i = strtol(nip, &cp, 0);
/* check for parse error */
if ((cp != nip) && (*cp == 0))
unit = i;
}
rootdev = MAKEBOOTDEV(major, slice, unit, partition);
DPRINTF("dev is 0x%x\n", rootdev);
return (rootdev);
}
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