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diff --git a/gpxe/src/arch/i386/interface/pcbios/int13.c b/gpxe/src/arch/i386/interface/pcbios/int13.c
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@@ -1,715 +0,0 @@
-/*
- * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-FILE_LICENCE ( GPL2_OR_LATER );
-
-#include <stdint.h>
-#include <limits.h>
-#include <byteswap.h>
-#include <errno.h>
-#include <assert.h>
-#include <gpxe/list.h>
-#include <gpxe/blockdev.h>
-#include <gpxe/memmap.h>
-#include <realmode.h>
-#include <bios.h>
-#include <biosint.h>
-#include <bootsector.h>
-#include <int13.h>
-
-/** @file
- *
- * INT 13 emulation
- *
- * This module provides a mechanism for exporting block devices via
- * the BIOS INT 13 disk interrupt interface.
- *
- */
-
-/** Vector for chaining to other INT 13 handlers */
-static struct segoff __text16 ( int13_vector );
-#define int13_vector __use_text16 ( int13_vector )
-
-/** Assembly wrapper */
-extern void int13_wrapper ( void );
-
-/** List of registered emulated drives */
-static LIST_HEAD ( drives );
-
-/**
- * Number of BIOS drives
- *
- * Note that this is the number of drives in the system as a whole
- * (i.e. a mirror of the counter at 40:75), rather than a count of the
- * number of emulated drives.
- */
-static uint8_t num_drives;
-
-/**
- * Update BIOS drive count
- */
-static void int13_set_num_drives ( void ) {
- struct int13_drive *drive;
-
- /* Get current drive count */
- get_real ( num_drives, BDA_SEG, BDA_NUM_DRIVES );
-
- /* Ensure count is large enough to cover all of our emulated drives */
- list_for_each_entry ( drive, &drives, list ) {
- if ( num_drives <= ( drive->drive & 0x7f ) )
- num_drives = ( ( drive->drive & 0x7f ) + 1 );
- }
-
- /* Update current drive count */
- put_real ( num_drives, BDA_SEG, BDA_NUM_DRIVES );
-}
-
-/**
- * Check number of drives
- */
-static void int13_check_num_drives ( void ) {
- uint8_t check_num_drives;
-
- get_real ( check_num_drives, BDA_SEG, BDA_NUM_DRIVES );
- if ( check_num_drives != num_drives ) {
- int13_set_num_drives();
- DBG ( "INT13 fixing up number of drives from %d to %d\n",
- check_num_drives, num_drives );
- }
-}
-
-/**
- * INT 13, 00 - Reset disk system
- *
- * @v drive Emulated drive
- * @ret status Status code
- */
-static int int13_reset ( struct int13_drive *drive __unused,
- struct i386_all_regs *ix86 __unused ) {
- DBG ( "Reset drive\n" );
- return 0;
-}
-
-/**
- * INT 13, 01 - Get status of last operation
- *
- * @v drive Emulated drive
- * @ret status Status code
- */
-static int int13_get_last_status ( struct int13_drive *drive,
- struct i386_all_regs *ix86 __unused ) {
- DBG ( "Get status of last operation\n" );
- return drive->last_status;
-}
-
-/**
- * Read / write sectors
- *
- * @v drive Emulated drive
- * @v al Number of sectors to read or write (must be nonzero)
- * @v ch Low bits of cylinder number
- * @v cl (bits 7:6) High bits of cylinder number
- * @v cl (bits 5:0) Sector number
- * @v dh Head number
- * @v es:bx Data buffer
- * @v io Read / write method
- * @ret status Status code
- * @ret al Number of sectors read or written
- */
-static int int13_rw_sectors ( struct int13_drive *drive,
- struct i386_all_regs *ix86,
- int ( * io ) ( struct block_device *blockdev,
- uint64_t block,
- unsigned long count,
- userptr_t buffer ) ) {
- struct block_device *blockdev = drive->blockdev;
- unsigned int cylinder, head, sector;
- unsigned long lba;
- unsigned int count;
- userptr_t buffer;
- int rc;
-
- /* Validate blocksize */
- if ( blockdev->blksize != INT13_BLKSIZE ) {
- DBG ( "Invalid blocksize (%zd) for non-extended read/write\n",
- blockdev->blksize );
- return -INT13_STATUS_INVALID;
- }
-
- /* Calculate parameters */
- cylinder = ( ( ( ix86->regs.cl & 0xc0 ) << 2 ) | ix86->regs.ch );
- assert ( cylinder < drive->cylinders );
- head = ix86->regs.dh;
- assert ( head < drive->heads );
- sector = ( ix86->regs.cl & 0x3f );
- assert ( ( sector >= 1 ) && ( sector <= drive->sectors_per_track ) );
- lba = ( ( ( ( cylinder * drive->heads ) + head )
- * drive->sectors_per_track ) + sector - 1 );
- count = ix86->regs.al;
- buffer = real_to_user ( ix86->segs.es, ix86->regs.bx );
-
- DBG ( "C/H/S %d/%d/%d = LBA %#lx <-> %04x:%04x (count %d)\n", cylinder,
- head, sector, lba, ix86->segs.es, ix86->regs.bx, count );
-
- /* Read from / write to block device */
- if ( ( rc = io ( blockdev, lba, count, buffer ) ) != 0 ) {
- DBG ( "INT 13 failed: %s\n", strerror ( rc ) );
- return -INT13_STATUS_READ_ERROR;
- }
-
- return 0;
-}
-
-/**
- * INT 13, 02 - Read sectors
- *
- * @v drive Emulated drive
- * @v al Number of sectors to read (must be nonzero)
- * @v ch Low bits of cylinder number
- * @v cl (bits 7:6) High bits of cylinder number
- * @v cl (bits 5:0) Sector number
- * @v dh Head number
- * @v es:bx Data buffer
- * @ret status Status code
- * @ret al Number of sectors read
- */
-static int int13_read_sectors ( struct int13_drive *drive,
- struct i386_all_regs *ix86 ) {
- DBG ( "Read: " );
- return int13_rw_sectors ( drive, ix86, drive->blockdev->op->read );
-}
-
-/**
- * INT 13, 03 - Write sectors
- *
- * @v drive Emulated drive
- * @v al Number of sectors to write (must be nonzero)
- * @v ch Low bits of cylinder number
- * @v cl (bits 7:6) High bits of cylinder number
- * @v cl (bits 5:0) Sector number
- * @v dh Head number
- * @v es:bx Data buffer
- * @ret status Status code
- * @ret al Number of sectors written
- */
-static int int13_write_sectors ( struct int13_drive *drive,
- struct i386_all_regs *ix86 ) {
- DBG ( "Write: " );
- return int13_rw_sectors ( drive, ix86, drive->blockdev->op->write );
-}
-
-/**
- * INT 13, 08 - Get drive parameters
- *
- * @v drive Emulated drive
- * @ret status Status code
- * @ret ch Low bits of maximum cylinder number
- * @ret cl (bits 7:6) High bits of maximum cylinder number
- * @ret cl (bits 5:0) Maximum sector number
- * @ret dh Maximum head number
- * @ret dl Number of drives
- */
-static int int13_get_parameters ( struct int13_drive *drive,
- struct i386_all_regs *ix86 ) {
- unsigned int max_cylinder = drive->cylinders - 1;
- unsigned int max_head = drive->heads - 1;
- unsigned int max_sector = drive->sectors_per_track; /* sic */
-
- DBG ( "Get drive parameters\n" );
-
- ix86->regs.ch = ( max_cylinder & 0xff );
- ix86->regs.cl = ( ( ( max_cylinder >> 8 ) << 6 ) | max_sector );
- ix86->regs.dh = max_head;
- get_real ( ix86->regs.dl, BDA_SEG, BDA_NUM_DRIVES );
- return 0;
-}
-
-/**
- * INT 13, 15 - Get disk type
- *
- * @v drive Emulated drive
- * @ret ah Type code
- * @ret cx:dx Sector count
- * @ret status Status code / disk type
- */
-static int int13_get_disk_type ( struct int13_drive *drive,
- struct i386_all_regs *ix86 ) {
- uint32_t blocks;
-
- DBG ( "Get disk type\n" );
- blocks = ( ( drive->blockdev->blocks <= 0xffffffffUL ) ?
- drive->blockdev->blocks : 0xffffffffUL );
- ix86->regs.cx = ( blocks >> 16 );
- ix86->regs.dx = ( blocks & 0xffff );
- return INT13_DISK_TYPE_HDD;
-}
-
-/**
- * INT 13, 41 - Extensions installation check
- *
- * @v drive Emulated drive
- * @v bx 0x55aa
- * @ret bx 0xaa55
- * @ret cx Extensions API support bitmap
- * @ret status Status code / API version
- */
-static int int13_extension_check ( struct int13_drive *drive __unused,
- struct i386_all_regs *ix86 ) {
- if ( ix86->regs.bx == 0x55aa ) {
- DBG ( "INT 13 extensions installation check\n" );
- ix86->regs.bx = 0xaa55;
- ix86->regs.cx = INT13_EXTENSION_LINEAR;
- return INT13_EXTENSION_VER_1_X;
- } else {
- return -INT13_STATUS_INVALID;
- }
-}
-
-/**
- * Extended read / write
- *
- * @v drive Emulated drive
- * @v ds:si Disk address packet
- * @v io Read / write method
- * @ret status Status code
- */
-static int int13_extended_rw ( struct int13_drive *drive,
- struct i386_all_regs *ix86,
- int ( * io ) ( struct block_device *blockdev,
- uint64_t block,
- unsigned long count,
- userptr_t buffer ) ) {
- struct block_device *blockdev = drive->blockdev;
- struct int13_disk_address addr;
- uint64_t lba;
- unsigned long count;
- userptr_t buffer;
- int rc;
-
- /* Read parameters from disk address structure */
- copy_from_real ( &addr, ix86->segs.ds, ix86->regs.si, sizeof ( addr ));
- lba = addr.lba;
- count = addr.count;
- buffer = real_to_user ( addr.buffer.segment, addr.buffer.offset );
-
- DBG ( "LBA %#llx <-> %04x:%04x (count %ld)\n", (unsigned long long)lba,
- addr.buffer.segment, addr.buffer.offset, count );
-
- /* Read from / write to block device */
- if ( ( rc = io ( blockdev, lba, count, buffer ) ) != 0 ) {
- DBG ( "INT 13 failed: %s\n", strerror ( rc ) );
- return -INT13_STATUS_READ_ERROR;
- }
-
- return 0;
-}
-
-/**
- * INT 13, 42 - Extended read
- *
- * @v drive Emulated drive
- * @v ds:si Disk address packet
- * @ret status Status code
- */
-static int int13_extended_read ( struct int13_drive *drive,
- struct i386_all_regs *ix86 ) {
- DBG ( "Extended read: " );
- return int13_extended_rw ( drive, ix86, drive->blockdev->op->read );
-}
-
-/**
- * INT 13, 43 - Extended write
- *
- * @v drive Emulated drive
- * @v ds:si Disk address packet
- * @ret status Status code
- */
-static int int13_extended_write ( struct int13_drive *drive,
- struct i386_all_regs *ix86 ) {
- DBG ( "Extended write: " );
- return int13_extended_rw ( drive, ix86, drive->blockdev->op->write );
-}
-
-/**
- * INT 13, 48 - Get extended parameters
- *
- * @v drive Emulated drive
- * @v ds:si Drive parameter table
- * @ret status Status code
- */
-static int int13_get_extended_parameters ( struct int13_drive *drive,
- struct i386_all_regs *ix86 ) {
- struct int13_disk_parameters params = {
- .bufsize = sizeof ( params ),
- .flags = INT13_FL_DMA_TRANSPARENT,
- .cylinders = drive->cylinders,
- .heads = drive->heads,
- .sectors_per_track = drive->sectors_per_track,
- .sectors = drive->blockdev->blocks,
- .sector_size = drive->blockdev->blksize,
- };
-
- DBG ( "Get extended drive parameters to %04x:%04x\n",
- ix86->segs.ds, ix86->regs.si );
-
- copy_to_real ( ix86->segs.ds, ix86->regs.si, &params,
- sizeof ( params ) );
- return 0;
-}
-
-/**
- * INT 13 handler
- *
- */
-static __asmcall void int13 ( struct i386_all_regs *ix86 ) {
- int command = ix86->regs.ah;
- unsigned int bios_drive = ix86->regs.dl;
- struct int13_drive *drive;
- int status;
-
- /* Check BIOS hasn't killed off our drive */
- int13_check_num_drives();
-
- list_for_each_entry ( drive, &drives, list ) {
-
- if ( bios_drive != drive->drive ) {
- /* Remap any accesses to this drive's natural number */
- if ( bios_drive == drive->natural_drive ) {
- DBG ( "INT 13,%04x (%02x) remapped to "
- "(%02x)\n", ix86->regs.ax,
- bios_drive, drive->drive );
- ix86->regs.dl = drive->drive;
- return;
- }
- continue;
- }
-
- DBG ( "INT 13,%04x (%02x): ", ix86->regs.ax, drive->drive );
-
- switch ( command ) {
- case INT13_RESET:
- status = int13_reset ( drive, ix86 );
- break;
- case INT13_GET_LAST_STATUS:
- status = int13_get_last_status ( drive, ix86 );
- break;
- case INT13_READ_SECTORS:
- status = int13_read_sectors ( drive, ix86 );
- break;
- case INT13_WRITE_SECTORS:
- status = int13_write_sectors ( drive, ix86 );
- break;
- case INT13_GET_PARAMETERS:
- status = int13_get_parameters ( drive, ix86 );
- break;
- case INT13_GET_DISK_TYPE:
- status = int13_get_disk_type ( drive, ix86 );
- break;
- case INT13_EXTENSION_CHECK:
- status = int13_extension_check ( drive, ix86 );
- break;
- case INT13_EXTENDED_READ:
- status = int13_extended_read ( drive, ix86 );
- break;
- case INT13_EXTENDED_WRITE:
- status = int13_extended_write ( drive, ix86 );
- break;
- case INT13_GET_EXTENDED_PARAMETERS:
- status = int13_get_extended_parameters ( drive, ix86 );
- break;
- default:
- DBG ( "*** Unrecognised INT 13 ***\n" );
- status = -INT13_STATUS_INVALID;
- break;
- }
-
- /* Store status for INT 13,01 */
- drive->last_status = status;
-
- /* Negative status indicates an error */
- if ( status < 0 ) {
- status = -status;
- DBG ( "INT 13 returning failure status %x\n", status );
- } else {
- ix86->flags &= ~CF;
- }
- ix86->regs.ah = status;
-
- /* Set OF to indicate to wrapper not to chain this call */
- ix86->flags |= OF;
-
- return;
- }
-}
-
-/**
- * Hook INT 13 handler
- *
- */
-static void hook_int13 ( void ) {
- /* Assembly wrapper to call int13(). int13() sets OF if we
- * should not chain to the previous handler. (The wrapper
- * clears CF and OF before calling int13()).
- */
- __asm__ __volatile__ (
- TEXT16_CODE ( "\nint13_wrapper:\n\t"
- /* Preserve %ax and %dx for future reference */
- "pushw %%bp\n\t"
- "movw %%sp, %%bp\n\t"
- "pushw %%ax\n\t"
- "pushw %%dx\n\t"
- /* Clear OF, set CF, call int13() */
- "orb $0, %%al\n\t"
- "stc\n\t"
- "pushl %0\n\t"
- "pushw %%cs\n\t"
- "call prot_call\n\t"
- /* Chain if OF not set */
- "jo 1f\n\t"
- "pushfw\n\t"
- "lcall *%%cs:int13_vector\n\t"
- "\n1:\n\t"
- /* Overwrite flags for iret */
- "pushfw\n\t"
- "popw 6(%%bp)\n\t"
- /* Fix up %dl:
- *
- * INT 13,15 : do nothing
- * INT 13,08 : load with number of drives
- * all others: restore original value
- */
- "cmpb $0x15, -1(%%bp)\n\t"
- "je 2f\n\t"
- "movb -4(%%bp), %%dl\n\t"
- "cmpb $0x08, -1(%%bp)\n\t"
- "jne 2f\n\t"
- "pushw %%ds\n\t"
- "pushw %1\n\t"
- "popw %%ds\n\t"
- "movb %c2, %%dl\n\t"
- "popw %%ds\n\t"
- /* Return */
- "\n2:\n\t"
- "movw %%bp, %%sp\n\t"
- "popw %%bp\n\t"
- "iret\n\t" )
- : : "i" ( int13 ), "i" ( BDA_SEG ), "i" ( BDA_NUM_DRIVES ) );
-
- hook_bios_interrupt ( 0x13, ( unsigned int ) int13_wrapper,
- &int13_vector );
-}
-
-/**
- * Unhook INT 13 handler
- */
-static void unhook_int13 ( void ) {
- unhook_bios_interrupt ( 0x13, ( unsigned int ) int13_wrapper,
- &int13_vector );
-}
-
-/**
- * Guess INT 13 drive geometry
- *
- * @v drive Emulated drive
- *
- * Guesses the drive geometry by inspecting the partition table.
- */
-static void guess_int13_geometry ( struct int13_drive *drive ) {
- struct master_boot_record mbr;
- struct partition_table_entry *partition;
- unsigned int guessed_heads = 255;
- unsigned int guessed_sectors_per_track = 63;
- unsigned long blocks;
- unsigned long blocks_per_cyl;
- unsigned int i;
-
- /* Don't even try when the blksize is invalid for C/H/S access */
- if ( drive->blockdev->blksize != INT13_BLKSIZE )
- return;
-
- /* Scan through partition table and modify guesses for heads
- * and sectors_per_track if we find any used partitions.
- */
- if ( drive->blockdev->op->read ( drive->blockdev, 0, 1,
- virt_to_user ( &mbr ) ) == 0 ) {
- for ( i = 0 ; i < 4 ; i++ ) {
- partition = &mbr.partitions[i];
- if ( ! partition->type )
- continue;
- guessed_heads =
- ( PART_HEAD ( partition->chs_end ) + 1 );
- guessed_sectors_per_track =
- PART_SECTOR ( partition->chs_end );
- DBG ( "Guessing C/H/S xx/%d/%d based on partition "
- "%d\n", guessed_heads,
- guessed_sectors_per_track, ( i + 1 ) );
- }
- } else {
- DBG ( "Could not read partition table to guess geometry\n" );
- }
-
- /* Apply guesses if no geometry already specified */
- if ( ! drive->heads )
- drive->heads = guessed_heads;
- if ( ! drive->sectors_per_track )
- drive->sectors_per_track = guessed_sectors_per_track;
- if ( ! drive->cylinders ) {
- /* Avoid attempting a 64-bit divide on a 32-bit system */
- blocks = ( ( drive->blockdev->blocks <= ULONG_MAX ) ?
- drive->blockdev->blocks : ULONG_MAX );
- blocks_per_cyl = ( drive->heads * drive->sectors_per_track );
- assert ( blocks_per_cyl != 0 );
- drive->cylinders = ( blocks / blocks_per_cyl );
- if ( drive->cylinders > 1024 )
- drive->cylinders = 1024;
- }
-}
-
-/**
- * Register INT 13 emulated drive
- *
- * @v drive Emulated drive
- *
- * Registers the drive with the INT 13 emulation subsystem, and hooks
- * the INT 13 interrupt vector (if not already hooked).
- *
- * The underlying block device must be valid. A drive number and
- * geometry will be assigned if left blank.
- */
-void register_int13_drive ( struct int13_drive *drive ) {
- uint8_t num_drives;
-
- /* Give drive a default geometry if none specified */
- guess_int13_geometry ( drive );
-
- /* Assign natural drive number */
- get_real ( num_drives, BDA_SEG, BDA_NUM_DRIVES );
- drive->natural_drive = ( num_drives | 0x80 );
-
- /* Assign drive number */
- if ( ( drive->drive & 0xff ) == 0xff ) {
- /* Drive number == -1 => use natural drive number */
- drive->drive = drive->natural_drive;
- } else {
- /* Use specified drive number (+0x80 if necessary) */
- drive->drive |= 0x80;
- }
-
- DBG ( "Registered INT13 drive %02x (naturally %02x) with C/H/S "
- "geometry %d/%d/%d\n", drive->drive, drive->natural_drive,
- drive->cylinders, drive->heads, drive->sectors_per_track );
-
- /* Hook INT 13 vector if not already hooked */
- if ( list_empty ( &drives ) )
- hook_int13();
-
- /* Add to list of emulated drives */
- list_add ( &drive->list, &drives );
-
- /* Update BIOS drive count */
- int13_set_num_drives();
-}
-
-/**
- * Unregister INT 13 emulated drive
- *
- * @v drive Emulated drive
- *
- * Unregisters the drive from the INT 13 emulation subsystem. If this
- * is the last emulated drive, the INT 13 vector is unhooked (if
- * possible).
- */
-void unregister_int13_drive ( struct int13_drive *drive ) {
- /* Remove from list of emulated drives */
- list_del ( &drive->list );
-
- /* Should adjust BIOS drive count, but it's difficult to do so
- * reliably.
- */
-
- DBG ( "Unregistered INT13 drive %02x\n", drive->drive );
-
- /* Unhook INT 13 vector if no more drives */
- if ( list_empty ( &drives ) )
- unhook_int13();
-}
-
-/**
- * Attempt to boot from an INT 13 drive
- *
- * @v drive Drive number
- * @ret rc Return status code
- *
- * This boots from the specified INT 13 drive by loading the Master
- * Boot Record to 0000:7c00 and jumping to it. INT 18 is hooked to
- * capture an attempt by the MBR to boot the next device. (This is
- * the closest thing to a return path from an MBR).
- *
- * Note that this function can never return success, by definition.
- */
-int int13_boot ( unsigned int drive ) {
- struct memory_map memmap;
- int status, signature;
- int discard_c, discard_d;
- int rc;
-
- DBG ( "Booting from INT 13 drive %02x\n", drive );
-
- /* Use INT 13 to read the boot sector */
- __asm__ __volatile__ ( REAL_CODE ( "pushw %%es\n\t"
- "pushw $0\n\t"
- "popw %%es\n\t"
- "stc\n\t"
- "sti\n\t"
- "int $0x13\n\t"
- "sti\n\t" /* BIOS bugs */
- "jc 1f\n\t"
- "xorl %%eax, %%eax\n\t"
- "\n1:\n\t"
- "movzwl %%es:0x7dfe, %%ebx\n\t"
- "popw %%es\n\t" )
- : "=a" ( status ), "=b" ( signature ),
- "=c" ( discard_c ), "=d" ( discard_d )
- : "a" ( 0x0201 ), "b" ( 0x7c00 ),
- "c" ( 1 ), "d" ( drive ) );
- if ( status )
- return -EIO;
-
- /* Check signature is correct */
- if ( signature != be16_to_cpu ( 0x55aa ) ) {
- DBG ( "Invalid disk signature %#04x (should be 0x55aa)\n",
- cpu_to_be16 ( signature ) );
- return -ENOEXEC;
- }
-
- /* Dump out memory map prior to boot, if memmap debugging is
- * enabled. Not required for program flow, but we have so
- * many problems that turn out to be memory-map related that
- * it's worth doing.
- */
- get_memmap ( &memmap );
-
- /* Jump to boot sector */
- if ( ( rc = call_bootsector ( 0x0, 0x7c00, drive ) ) != 0 ) {
- DBG ( "INT 13 drive %02x boot returned: %s\n",
- drive, strerror ( rc ) );
- return rc;
- }
-
- return -ECANCELED; /* -EIMPOSSIBLE */
-}
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