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diff --git a/contrib/syslinux-4.02/gpxe/src/arch/i386/interface/pcbios/int13.c b/contrib/syslinux-4.02/gpxe/src/arch/i386/interface/pcbios/int13.c
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+/*
+ * 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 */
+}
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-05-17 15:05:34 +0200