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/* ----------------------------------------------------------------------- *
*
* Copyright 2009 Pierre-Alexandre Meyer
*
* Some parts borrowed from chain.c32:
*
* Copyright 2003-2009 H. Peter Anvin - All Rights Reserved
* Copyright 2009 Intel Corporation; author: H. Peter Anvin
*
* This file is part of Syslinux, and is made available under
* the terms of the GNU General Public License version 2.
*
* ----------------------------------------------------------------------- */
#include <com32.h>
#include <stdlib.h>
#include <string.h>
#include <disk/common.h>
#include <disk/errno_disk.h>
#include <disk/read.h>
#include <disk/util.h>
#include <disk/write.h>
/**
* write_sectors - write several sectors from disk
* @drive_info: driveinfo struct describing the disk
* @lba: Position to write
* @data: Buffer to write
* @size: Size of the buffer (number of sectors)
*
* Return the number of sectors write on success or -1 on failure.
* errno_disk contains the error number.
**/
int write_sectors(const struct driveinfo *drive_info, const unsigned int lba,
const void *data, const int size)
{
com32sys_t inreg, outreg;
struct ebios_dapa *dapa = __com32.cs_bounce;
void *buf = (char *)__com32.cs_bounce + size;
memcpy(buf, data, size);
memset(&inreg, 0, sizeof inreg);
if (drive_info->ebios) {
dapa->len = sizeof(*dapa);
dapa->count = size;
dapa->off = OFFS(buf);
dapa->seg = SEG(buf);
dapa->lba = lba;
inreg.esi.w[0] = OFFS(dapa);
inreg.ds = SEG(dapa);
inreg.edx.b[0] = drive_info->disk;
inreg.eax.w[0] = 0x4300; /* Extended write */
} else {
unsigned int c, h, s;
if (!drive_info->cbios) { // XXX errno
/* We failed to get the geometry */
if (lba)
return -1; /* Can only write MBR */
s = 1;
h = 0;
c = 0;
} else
lba_to_chs(drive_info, lba, &s, &h, &c);
// XXX errno
if (s > 63 || h > 256 || c > 1023)
return -1;
inreg.eax.w[0] = 0x0301; /* Write one sector */
inreg.ecx.b[1] = c & 0xff;
inreg.ecx.b[0] = s + (c >> 6);
inreg.edx.b[1] = h;
inreg.edx.b[0] = drive_info->disk;
inreg.ebx.w[0] = OFFS(buf);
inreg.es = SEG(buf);
}
/* Perform the write */
if (int13_retry(&inreg, &outreg)) {
errno_disk = outreg.eax.b[1];
return -1; /* Give up */
} else
return size;
}
/**
* write_verify_sectors - write several sectors from disk
* @drive_info: driveinfo struct describing the disk
* @lba: Position to write
* @data: Buffer to write
**/
int write_verify_sector(struct driveinfo *drive_info,
const unsigned int lba, const void *data)
{
return write_verify_sectors(drive_info, lba, data, SECTOR);
}
/**
* write_verify_sectors - write several sectors from disk
* @drive_info: driveinfo struct describing the disk
* @lba: Position to write
* @data: Buffer to write
* @size: Size of the buffer (number of sectors)
**/
int write_verify_sectors(struct driveinfo *drive_info,
const unsigned int lba,
const void *data, const int size)
{
char *rb = malloc(SECTOR * size * sizeof(char));
int status;
if (write_sectors(drive_info, lba, data, size) == -1)
return -1; /* Write failure */
if (read_sectors(drive_info, rb, lba, size) == -1)
return -1; /* Readback failure */
status = memcmp(data, rb, SECTOR * size);
free(rb);
return status ? -1 : 0;
}
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