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diff --git a/src/VBox/Devices/PC/BIOS/disk.c b/src/VBox/Devices/PC/BIOS/disk.c
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+++ b/src/VBox/Devices/PC/BIOS/disk.c
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+/* $Id: disk.c $ */
+/** @file
+ * PC BIOS - ???
+ */
+
+/*
+ * Copyright (C) 2006-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ * --------------------------------------------------------------------
+ *
+ * This code is based on:
+ *
+ * ROM BIOS for use with Bochs/Plex86/QEMU emulation environment
+ *
+ * Copyright (C) 2002 MandrakeSoft S.A.
+ *
+ * MandrakeSoft S.A.
+ * 43, rue d'Aboukir
+ * 75002 Paris - France
+ * http://www.linux-mandrake.com/
+ * http://www.mandrakesoft.com/
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+/*
+ * Oracle LGPL Disclaimer: For the avoidance of doubt, except that if any license choice
+ * other than GPL or LGPL is available it will apply instead, Oracle elects to use only
+ * the Lesser General Public License version 2.1 (LGPLv2) at this time for any software where
+ * a choice of LGPL license versions is made available with the language indicating
+ * that LGPLv2 or any later version may be used, or where a choice of which version
+ * of the LGPL is applied is otherwise unspecified.
+ */
+
+
+#include <stdint.h>
+#include "biosint.h"
+#include "inlines.h"
+#include "ebda.h"
+#include "ata.h"
+
+
+#if DEBUG_INT13_HD
+# define BX_DEBUG_INT13_HD(...) BX_DEBUG(__VA_ARGS__)
+#else
+# define BX_DEBUG_INT13_HD(...)
+#endif
+
+/* Generic disk read/write routine signature. */
+typedef __fastcall (* dsk_rw_func)(bio_dsk_t __far *bios_dsk);
+
+/* Controller specific disk access routines. Declared as a union to reduce
+ * the need for conditionals when choosing between read/write functions.
+ * Note that we get away with using near pointers, which is nice.
+ */
+typedef union {
+ struct {
+ dsk_rw_func read;
+ dsk_rw_func write;
+ } s;
+ dsk_rw_func a[2];
+} dsk_acc_t;
+
+/* Pointers to HW specific disk access routines. */
+dsk_acc_t dskacc[DSKTYP_CNT] = {
+ [DSK_TYPE_ATA] = { ata_read_sectors, ata_write_sectors },
+#ifdef VBOX_WITH_AHCI
+ [DSK_TYPE_AHCI] = { ahci_read_sectors, ahci_write_sectors },
+#endif
+#ifdef VBOX_WITH_SCSI
+ [DSK_TYPE_SCSI] = { scsi_read_sectors, scsi_write_sectors },
+#endif
+};
+
+
+/// @todo put in a header
+#define AX r.gr.u.r16.ax
+#define BX r.gr.u.r16.bx
+#define CX r.gr.u.r16.cx
+#define DX r.gr.u.r16.dx
+#define SI r.gr.u.r16.si
+#define DI r.gr.u.r16.di
+#define BP r.gr.u.r16.bp
+#define ELDX r.gr.u.r16.sp
+#define DS r.ds
+#define ES r.es
+#define FLAGS r.ra.flags.u.r16.flags
+
+
+/*
+ * Build translated CHS geometry given a disk size in sectors. Based on
+ * Phoenix EDD 3.0. This is used as a fallback to generate sane logical
+ * geometry in case none was provided in CMOS.
+ */
+void set_geom_lba(chs_t __far *lgeo, uint64_t nsectors64)
+{
+ uint32_t limit = 8257536; /* 1024 * 128 * 63 */
+ uint32_t nsectors;
+ unsigned heads = 255;
+ int i;
+
+ nsectors = (nsectors64 >> 32) ? 0xFFFFFFFFL : (uint32_t)nsectors64;
+ /* Start with ~4GB limit, go down to 504MB. */
+ for (i = 0; i < 4; ++i) {
+ if (nsectors <= limit)
+ heads = (heads + 1) / 2;
+ limit /= 2;
+ }
+
+ lgeo->cylinders = nsectors / (heads * 63UL);
+ if (lgeo->cylinders > 1024)
+ lgeo->cylinders = 1024;
+ lgeo->heads = heads;
+ lgeo->spt = 63; /* Always 63 sectors per track, the maximum. */
+}
+
+int edd_fill_dpt(dpt_t __far *dpt, bio_dsk_t __far *bios_dsk, uint8_t device)
+{
+ uint16_t ebda_seg = read_word(0x0040,0x000E);
+
+ /* Check if buffer is large enough. */
+ if (dpt->size < 0x1a)
+ return -1;
+
+ /* Fill in EDD 1.x table. */
+ if (dpt->size >= 0x1a) {
+ uint64_t lba;
+
+ dpt->size = 0x1a;
+ dpt->blksize = bios_dsk->devices[device].blksize;
+
+ if (bios_dsk->devices[device].device == DSK_DEVICE_CDROM) {
+ dpt->infos = 0x74; /* Removable, media change, lockable, max values */
+ dpt->cylinders = 0xffffffff;
+ dpt->heads = 0xffffffff;
+ dpt->spt = 0xffffffff;
+ dpt->sector_count1 = 0xffffffff;
+ dpt->sector_count2 = 0xffffffff;
+ } else {
+ dpt->infos = 0x02; // geometry is valid
+ dpt->cylinders = bios_dsk->devices[device].pchs.cylinders;
+ dpt->heads = bios_dsk->devices[device].pchs.heads;
+ dpt->spt = bios_dsk->devices[device].pchs.spt;
+ lba = bios_dsk->devices[device].sectors;
+ dpt->sector_count1 = lba;
+ dpt->sector_count2 = lba >> 32;
+ }
+ }
+
+ /* Fill in EDD 2.x table. */
+ if (dpt->size >= 0x1e) {
+ uint8_t channel, irq, mode, checksum, i, xlation;
+ uint16_t iobase1, iobase2, options;
+
+ dpt->size = 0x1e;
+ dpt->dpte_segment = ebda_seg;
+ dpt->dpte_offset = (uint16_t)&EbdaData->bdisk.dpte;
+
+ // Fill in dpte
+ channel = device / 2;
+ iobase1 = bios_dsk->channels[channel].iobase1;
+ iobase2 = bios_dsk->channels[channel].iobase2;
+ irq = bios_dsk->channels[channel].irq;
+ mode = bios_dsk->devices[device].mode;
+ xlation = bios_dsk->devices[device].translation;
+
+ options = (xlation == GEO_TRANSLATION_NONE ? 0 : 1 << 3); /* CHS translation */
+ options |= (1 << 4); /* LBA translation */
+ if (bios_dsk->devices[device].device == DSK_DEVICE_CDROM) {
+ options |= (1 << 5); /* Removable device */
+ options |= (1 << 6); /* ATAPI device */
+ }
+#if VBOX_BIOS_CPU >= 80386
+ options |= (mode == ATA_MODE_PIO32 ? 1 : 0 << 7);
+#endif
+ options |= (xlation == GEO_TRANSLATION_LBA ? 1 : 0 << 9);
+ options |= (xlation == GEO_TRANSLATION_RECHS ? 3 : 0 << 9);
+
+ bios_dsk->dpte.iobase1 = iobase1;
+ bios_dsk->dpte.iobase2 = iobase2;
+ bios_dsk->dpte.prefix = (0xe | (device % 2)) << 4;
+ bios_dsk->dpte.unused = 0xcb;
+ bios_dsk->dpte.irq = irq;
+ bios_dsk->dpte.blkcount = 1;
+ bios_dsk->dpte.dma = 0;
+ bios_dsk->dpte.pio = 0;
+ bios_dsk->dpte.options = options;
+ bios_dsk->dpte.reserved = 0;
+ bios_dsk->dpte.revision = 0x11;
+
+ checksum = 0;
+ for (i = 0; i < 15; ++i)
+ checksum += read_byte(ebda_seg, (uint16_t)&EbdaData->bdisk.dpte + i);
+ checksum = -checksum;
+ bios_dsk->dpte.checksum = checksum;
+ }
+
+ /* Fill in EDD 3.x table. */
+ if (dpt->size >= 0x42) {
+ uint8_t channel, iface, checksum, i;
+ uint16_t iobase1;
+
+ channel = device / 2;
+ iface = bios_dsk->channels[channel].iface;
+ iobase1 = bios_dsk->channels[channel].iobase1;
+
+ dpt->size = 0x42;
+ dpt->key = 0xbedd;
+ dpt->dpi_length = 0x24;
+ dpt->reserved1 = 0;
+ dpt->reserved2 = 0;
+
+ if (iface == ATA_IFACE_ISA) {
+ dpt->host_bus[0] = 'I';
+ dpt->host_bus[1] = 'S';
+ dpt->host_bus[2] = 'A';
+ dpt->host_bus[3] = ' ';
+ }
+ else {
+ // FIXME PCI
+ }
+ dpt->iface_type[0] = 'A';
+ dpt->iface_type[1] = 'T';
+ dpt->iface_type[2] = 'A';
+ dpt->iface_type[3] = ' ';
+ dpt->iface_type[4] = ' ';
+ dpt->iface_type[5] = ' ';
+ dpt->iface_type[6] = ' ';
+ dpt->iface_type[7] = ' ';
+
+ if (iface == ATA_IFACE_ISA) {
+ ((uint16_t __far *)dpt->iface_path)[0] = iobase1;
+ ((uint16_t __far *)dpt->iface_path)[1] = 0;
+ ((uint32_t __far *)dpt->iface_path)[1] = 0;
+ }
+ else {
+ // FIXME PCI
+ }
+ ((uint16_t __far *)dpt->device_path)[0] = device & 1; // device % 2; @todo: correct?
+ ((uint16_t __far *)dpt->device_path)[1] = 0;
+ ((uint32_t __far *)dpt->device_path)[1] = 0;
+
+ checksum = 0;
+ for (i = 30; i < 64; i++)
+ checksum += ((uint8_t __far *)dpt)[i];
+ checksum = -checksum;
+ dpt->checksum = checksum;
+ }
+ return 0;
+}
+
+void BIOSCALL int13_harddisk(disk_regs_t r)
+{
+ uint32_t lba;
+ uint16_t cylinder, head, sector;
+ uint16_t nlc, nlh, nlspt;
+ uint16_t count;
+ uint8_t device, status;
+ bio_dsk_t __far *bios_dsk;
+
+ BX_DEBUG_INT13_HD("%s: AX=%04x BX=%04x CX=%04x DX=%04x ES=%04x\n", __func__, AX, BX, CX, DX, ES);
+
+ SET_IF(); /* INT 13h always returns with interrupts enabled. */
+
+ bios_dsk = read_word(0x0040,0x000E) :> &EbdaData->bdisk;
+ write_byte(0x0040, 0x008e, 0); // clear completion flag
+
+ // basic check : device has to be defined
+ if ( (GET_ELDL() < 0x80) || (GET_ELDL() >= 0x80 + BX_MAX_STORAGE_DEVICES) ) {
+ BX_DEBUG("%s: function %02x, ELDL out of range %02x\n", __func__, GET_AH(), GET_ELDL());
+ goto int13_fail;
+ }
+
+ // Get the ata channel
+ device = bios_dsk->hdidmap[GET_ELDL()-0x80];
+
+ // basic check : device has to be valid
+ if (device >= BX_MAX_STORAGE_DEVICES) {
+ BX_DEBUG("%s: function %02x, unmapped device for ELDL=%02x\n", __func__, GET_AH(), GET_ELDL());
+ goto int13_fail;
+ }
+
+ switch (GET_AH()) {
+
+ case 0x00: /* disk controller reset */
+#ifdef VBOX_WITH_SCSI
+ /* SCSI controller does not need a reset. */
+ if (!VBOX_IS_SCSI_DEVICE(device))
+#endif
+ ata_reset (device);
+ goto int13_success;
+ break;
+
+ case 0x01: /* read disk status */
+ status = read_byte(0x0040, 0x0074);
+ SET_AH(status);
+ SET_DISK_RET_STATUS(0);
+ /* set CF if error status read */
+ if (status) goto int13_fail_nostatus;
+ else goto int13_success_noah;
+ break;
+
+ case 0x02: // read disk sectors
+ case 0x03: // write disk sectors
+ case 0x04: // verify disk sectors
+
+ count = GET_AL();
+ cylinder = GET_CH();
+ cylinder |= ( ((uint16_t) GET_CL()) << 2) & 0x300;
+ sector = (GET_CL() & 0x3f);
+ head = GET_DH();
+
+ /* Segment and offset are in ES:BX. */
+ if ( (count > 128) || (count == 0) ) {
+ BX_INFO("%s: function %02x, count out of range!\n", __func__, GET_AH());
+ goto int13_fail;
+ }
+
+ /* Get the logical CHS geometry. */
+ nlc = bios_dsk->devices[device].lchs.cylinders;
+ nlh = bios_dsk->devices[device].lchs.heads;
+ nlspt = bios_dsk->devices[device].lchs.spt;
+
+ /* Sanity check the geometry. */
+ if( (cylinder >= nlc) || (head >= nlh) || (sector > nlspt )) {
+ BX_INFO("%s: function %02x, disk %02x, parameters out of range %04x/%04x/%04x!\n", __func__, GET_AH(), GET_DL(), cylinder, head, sector);
+ goto int13_fail;
+ }
+
+ // FIXME verify
+ if ( GET_AH() == 0x04 )
+ goto int13_success;
+
+ /* If required, translate LCHS to LBA and execute command. */
+ /// @todo The IS_SCSI_DEVICE check should be redundant...
+ if (( (bios_dsk->devices[device].pchs.heads != nlh) || (bios_dsk->devices[device].pchs.spt != nlspt)) || VBOX_IS_SCSI_DEVICE(device)) {
+ lba = ((((uint32_t)cylinder * (uint32_t)nlh) + (uint32_t)head) * (uint32_t)nlspt) + (uint32_t)sector - 1;
+ sector = 0; // this forces the command to be lba
+ }
+
+ BX_DEBUG_INT13_HD("%s: %d sectors from lba %lu @ %04x:%04x\n", __func__,
+ count, lba, ES, BX);
+
+ /* Clear the count of transferred sectors/bytes. */
+ bios_dsk->drqp.trsfsectors = 0;
+ bios_dsk->drqp.trsfbytes = 0;
+
+ /* Pass request information to low level disk code. */
+ bios_dsk->drqp.lba = lba;
+ bios_dsk->drqp.buffer = MK_FP(ES, BX);
+ bios_dsk->drqp.nsect = count;
+ bios_dsk->drqp.sect_sz = 512; /// @todo device specific?
+ bios_dsk->drqp.cylinder = cylinder;
+ bios_dsk->drqp.head = head;
+ bios_dsk->drqp.sector = sector;
+ bios_dsk->drqp.dev_id = device;
+
+ status = dskacc[bios_dsk->devices[device].type].a[GET_AH() - 0x02](bios_dsk);
+
+ // Set nb of sector transferred
+ SET_AL(bios_dsk->drqp.trsfsectors);
+
+ if (status != 0) {
+ BX_INFO("%s: function %02x, error %02x !\n", __func__, GET_AH(), status);
+ SET_AH(0x0c);
+ goto int13_fail_noah;
+ }
+
+ goto int13_success;
+ break;
+
+ case 0x05: /* format disk track */
+ BX_INFO("format disk track called\n");
+ goto int13_success;
+ break;
+
+ case 0x08: /* read disk drive parameters */
+
+ /* Get the logical geometry from internal table. */
+ nlc = bios_dsk->devices[device].lchs.cylinders;
+ nlh = bios_dsk->devices[device].lchs.heads;
+ nlspt = bios_dsk->devices[device].lchs.spt;
+
+ count = bios_dsk->hdcount;
+ /* Maximum cylinder number is just one less than the number of cylinders. */
+ nlc = nlc - 1; /* 0 based , last sector not used */
+ SET_AL(0);
+ SET_CH(nlc & 0xff);
+ SET_CL(((nlc >> 2) & 0xc0) | (nlspt & 0x3f));
+ SET_DH(nlh - 1);
+ SET_DL(count); /* FIXME returns 0, 1, or n hard drives */
+
+ // FIXME should set ES & DI
+ /// @todo Actually, the above comment is nonsense.
+
+ goto int13_success;
+ break;
+
+ case 0x10: /* check drive ready */
+ // should look at 40:8E also???
+
+ // Read the status from controller
+ status = inb(bios_dsk->channels[device/2].iobase1 + ATA_CB_STAT);
+ if ( (status & ( ATA_CB_STAT_BSY | ATA_CB_STAT_RDY )) == ATA_CB_STAT_RDY ) {
+ goto int13_success;
+ } else {
+ SET_AH(0xAA);
+ goto int13_fail_noah;
+ }
+ break;
+
+ case 0x15: /* read disk drive size */
+
+ /* Get the physical geometry from internal table. */
+ cylinder = bios_dsk->devices[device].pchs.cylinders;
+ head = bios_dsk->devices[device].pchs.heads;
+ sector = bios_dsk->devices[device].pchs.spt;
+
+ /* Calculate sector count seen by old style INT 13h. */
+ lba = (uint32_t)cylinder * head * sector;
+ CX = lba >> 16;
+ DX = lba & 0xffff;
+
+ SET_AH(3); // hard disk accessible
+ goto int13_success_noah;
+ break;
+
+ case 0x09: /* initialize drive parameters */
+ case 0x0c: /* seek to specified cylinder */
+ case 0x0d: /* alternate disk reset */
+ case 0x11: /* recalibrate */
+ case 0x14: /* controller internal diagnostic */
+ BX_INFO("%s: function %02xh unimplemented, returns success\n", __func__, GET_AH());
+ goto int13_success;
+ break;
+
+ case 0x0a: /* read disk sectors with ECC */
+ case 0x0b: /* write disk sectors with ECC */
+ case 0x18: // set media type for format
+ default:
+ BX_INFO("%s: function %02xh unsupported, returns fail\n", __func__, GET_AH());
+ goto int13_fail;
+ break;
+ }
+
+int13_fail:
+ SET_AH(0x01); // defaults to invalid function in AH or invalid parameter
+int13_fail_noah:
+ SET_DISK_RET_STATUS(GET_AH());
+int13_fail_nostatus:
+ SET_CF(); // error occurred
+ return;
+
+int13_success:
+ SET_AH(0x00); // no error
+int13_success_noah:
+ SET_DISK_RET_STATUS(0x00);
+ CLEAR_CF(); // no error
+ return;
+}
+
+void BIOSCALL int13_harddisk_ext(disk_regs_t r)
+{
+ uint64_t lba;
+ uint16_t segment, offset;
+ uint8_t device, status;
+ uint16_t count;
+ uint8_t type;
+ bio_dsk_t __far *bios_dsk;
+ int13ext_t __far *i13_ext;
+#if 0
+ uint16_t ebda_seg = read_word(0x0040,0x000E);
+ uint16_t npc, nph, npspt;
+ uint16_t size;
+ dpt_t __far *dpt;
+#endif
+
+ bios_dsk = read_word(0x0040,0x000E) :> &EbdaData->bdisk;
+
+ BX_DEBUG_INT13_HD("%s: AX=%04x BX=%04x CX=%04x DX=%04x ES=%04x DS=%04x SI=%04x\n",
+ __func__, AX, BX, CX, DX, ES, DS, SI);
+
+ write_byte(0x0040, 0x008e, 0); // clear completion flag
+
+ // basic check : device has to be defined
+ if ( (GET_ELDL() < 0x80) || (GET_ELDL() >= 0x80 + BX_MAX_STORAGE_DEVICES) ) {
+ BX_DEBUG("%s: function %02x, ELDL out of range %02x\n", __func__, GET_AH(), GET_ELDL());
+ goto int13x_fail;
+ }
+
+ // Get the ata channel
+ device = bios_dsk->hdidmap[GET_ELDL()-0x80];
+
+ // basic check : device has to be valid
+ if (device >= BX_MAX_STORAGE_DEVICES) {
+ BX_DEBUG("%s: function %02x, unmapped device for ELDL=%02x\n", __func__, GET_AH(), GET_ELDL());
+ goto int13x_fail;
+ }
+
+ switch (GET_AH()) {
+ case 0x41: // IBM/MS installation check
+ BX=0xaa55; // install check
+ SET_AH(0x30); // EDD 3.0
+ CX=0x0007; // ext disk access and edd, removable supported
+ goto int13x_success_noah;
+ break;
+
+ case 0x42: // IBM/MS extended read
+ case 0x43: // IBM/MS extended write
+ case 0x44: // IBM/MS verify
+ case 0x47: // IBM/MS extended seek
+
+ /* Get a pointer to the extended structure. */
+ i13_ext = DS :> (int13ext_t *)SI;
+
+ count = i13_ext->count;
+ segment = i13_ext->segment;
+ offset = i13_ext->offset;
+
+ // Get 64 bits lba and check
+ lba = i13_ext->lba2;
+ lba <<= 32;
+ lba |= i13_ext->lba1;
+
+ BX_DEBUG_INT13_HD("%s: %d sectors from LBA 0x%llx @ %04x:%04x\n", __func__,
+ count, lba, segment, offset);
+
+ type = bios_dsk->devices[device].type;
+ if (lba >= bios_dsk->devices[device].sectors) {
+ BX_INFO("%s: function %02x. LBA out of range\n", __func__, GET_AH());
+ goto int13x_fail;
+ }
+
+ /* Don't bother with seek or verify. */
+ if (( GET_AH() == 0x44 ) || ( GET_AH() == 0x47 ))
+ goto int13x_success;
+
+ /* Clear the count of transferred sectors/bytes. */
+ bios_dsk->drqp.trsfsectors = 0;
+ bios_dsk->drqp.trsfbytes = 0;
+
+ /* Pass request information to low level disk code. */
+ bios_dsk->drqp.lba = lba;
+ bios_dsk->drqp.buffer = MK_FP(segment, offset);
+ bios_dsk->drqp.nsect = count;
+ bios_dsk->drqp.sect_sz = 512; /// @todo device specific?
+ bios_dsk->drqp.sector = 0; /* Indicate LBA. */
+ bios_dsk->drqp.dev_id = device;
+
+ /* Execute the read or write command. */
+ status = dskacc[type].a[GET_AH() - 0x42](bios_dsk);
+ count = bios_dsk->drqp.trsfsectors;
+ i13_ext->count = count;
+
+ if (status != 0) {
+ BX_INFO("%s: function %02x, error %02x !\n", __func__, GET_AH(), status);
+ SET_AH(0x0c);
+ goto int13x_fail_noah;
+ }
+
+ goto int13x_success;
+ break;
+
+ case 0x45: // IBM/MS lock/unlock drive
+ case 0x49: // IBM/MS extended media change
+ goto int13x_success; // Always success for HD
+ break;
+
+ case 0x46: // IBM/MS eject media
+ SET_AH(0xb2); // Volume Not Removable
+ goto int13x_fail_noah; // Always fail for HD
+ break;
+
+ case 0x48: // IBM/MS get drive parameters
+ if (edd_fill_dpt(DS :> (dpt_t *)SI, bios_dsk, device))
+ goto int13x_fail;
+ else
+ goto int13x_success;
+ break;
+
+ case 0x4e: // // IBM/MS set hardware configuration
+ // DMA, prefetch, PIO maximum not supported
+ switch (GET_AL()) {
+ case 0x01:
+ case 0x03:
+ case 0x04:
+ case 0x06:
+ goto int13x_success;
+ break;
+ default :
+ goto int13x_fail;
+ }
+ break;
+
+ case 0x50: // IBM/MS send packet command
+ default:
+ BX_INFO("%s: function %02xh unsupported, returns fail\n", __func__, GET_AH());
+ goto int13x_fail;
+ break;
+ }
+
+int13x_fail:
+ SET_AH(0x01); // defaults to invalid function in AH or invalid parameter
+int13x_fail_noah:
+ SET_DISK_RET_STATUS(GET_AH());
+ SET_CF(); // error occurred
+ return;
+
+int13x_success:
+ SET_AH(0x00); // no error
+int13x_success_noah:
+ SET_DISK_RET_STATUS(0x00);
+ CLEAR_CF(); // no error
+ return;
+}
+
+/* Avoid saving general registers already saved by caller (PUSHA). */
+#pragma aux int13_harddisk modify [di si cx dx bx];
+#pragma aux int13_harddisk_ext modify [di si cx dx bx];
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-30 04:42:08 +0000