| /* common.c - miscellaneous shared variables and routines */ |
| /* |
| * GRUB -- GRand Unified Bootloader |
| * Copyright (C) 1999,2000,2001,2002,2004 Free Software Foundation, Inc. |
| * |
| * 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 |
| * (at your option) 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. |
| */ |
| |
| #include <shared.h> |
| #include <iso9660.h> |
| |
| #ifdef SUPPORT_DISKLESS |
| # define GRUB 1 |
| # include <etherboot.h> |
| #endif |
| |
| /* |
| * Shared BIOS/boot data. |
| */ |
| |
| struct multiboot_info mbi; |
| unsigned long saved_drive; |
| unsigned long saved_partition; |
| //unsigned long cdrom_drives[8] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}; |
| unsigned long cdrom_drive = GRUB_INVALID_DRIVE; |
| unsigned long force_cdrom_as_boot_device = 1; |
| unsigned long ram_drive; |
| unsigned long rd_base = 0; /* Note the rd_base value of -1 invalidates the ram drive. */ |
| unsigned long rd_size = 0; /* The rd_size 0 stands for 4GB, not for length of 0. */ |
| #ifndef STAGE1_5 |
| unsigned long saved_mem_upper; |
| |
| /* This saves the maximum size of extended memory (in KB). */ |
| unsigned long extended_memory; |
| #endif |
| int is64bit = 0; |
| int errorcheck = 1; |
| |
| /* |
| * Error code stuff. |
| */ |
| |
| grub_error_t errnum = ERR_NONE; |
| |
| #ifndef STAGE1_5 |
| |
| char *err_list[] = |
| { |
| [ERR_NONE] = 0, |
| [ERR_BAD_ARGUMENT] = "Invalid argument", |
| [ERR_BAD_FILENAME] = "Filename must be either an absolute pathname or blocklist", |
| [ERR_BAD_FILETYPE] = "Bad file or directory type", |
| [ERR_BAD_GZIP_DATA] = "Bad or corrupt data while decompressing file", |
| [ERR_BAD_GZIP_HEADER] = "Bad or incompatible header in compressed file", |
| [ERR_BAD_PART_TABLE] = "Partition table invalid or corrupt", |
| [ERR_BAD_VERSION] = "Mismatched or corrupt version of stage1/stage2", |
| [ERR_BELOW_1MB] = "Loading below 1MB is not supported", |
| [ERR_BOOT_COMMAND] = "Kernel must be loaded before booting", |
| [ERR_BOOT_FAILURE] = "Unknown boot failure", |
| [ERR_BOOT_FEATURES] = "Unsupported Multiboot features requested", |
| [ERR_DEV_FORMAT] = "Unrecognized device string", |
| [ERR_DEV_NEED_INIT] = "Device not initialized yet", |
| [ERR_DEV_VALUES] = "Invalid device requested", |
| [ERR_EXEC_FORMAT] = "Invalid or unsupported executable format", |
| [ERR_FILELENGTH] = "Filesystem compatibility error, cannot read whole file", |
| [ERR_FILE_NOT_FOUND] = "File not found", |
| [ERR_FSYS_CORRUPT] = "Inconsistent filesystem structure", |
| [ERR_FSYS_MOUNT] = "Cannot mount selected partition", |
| [ERR_GEOM] = "Selected cylinder exceeds maximum supported by BIOS", |
| [ERR_HD_VOL_START_0] = "The BPB hidden_sectors should not be zero for a hard-disk partition boot sector", |
| [ERR_IN_SITU_FLOPPY] = "Only hard drives could be mapped in situ.", |
| [ERR_IN_SITU_MEM] = "Should not use --mem together with --in-situ.", |
| [ERR_NEED_LX_KERNEL] = "Linux kernel must be loaded before initrd", |
| [ERR_NEED_MB_KERNEL] = "Multiboot kernel must be loaded before modules", |
| [ERR_NO_DISK] = "Selected disk does not exist", |
| [ERR_NO_DISK_SPACE] = "No spare sectors on the disk", |
| [ERR_NO_PART] = "No such partition", |
| [ERR_NO_HEADS] = "The number of heads must be specified. The `--heads=0' option tells map to choose a value(but maybe unsuitable) for you", |
| [ERR_NO_SECTORS] = "The number of sectors per track must be specified. The `--sectors-per-track=0' option tells map to choose a value(but maybe unsuitable) for you", |
| [ERR_NON_CONTIGUOUS] = "File for drive emulation must be in one contiguous disk area", |
| [ERR_NUMBER_OVERFLOW] = "Overflow while parsing number", |
| [ERR_NUMBER_PARSING] = "Error while parsing number", |
| [ERR_OUTSIDE_PART] = "Attempt to access block outside partition", |
| [ERR_PRIVILEGED] = "Must be authenticated", |
| [ERR_READ] = "Disk read error", |
| [ERR_SYMLINK_LOOP] = "Too many symbolic links", |
| [ERR_UNALIGNED] = "File is not sector aligned", |
| [ERR_UNRECOGNIZED] = "Unrecognized command", |
| [ERR_WONT_FIT] = "Selected item cannot fit into memory", |
| [ERR_WRITE] = "Disk write error", |
| [ERR_INT13_ON_HOOK] = "The int13 handler already on hook", |
| [ERR_INT13_OFF_HOOK] = "The int13 handler not yet on hook", |
| [ERR_NO_DRIVE_MAPPED] = "Refuse to hook int13 because of empty drive map table", |
| [ERR_INVALID_HEADS] = "Invalid heads. Should be between 0 and 256(0 means auto)", |
| [ERR_INVALID_SECTORS] = "Invalid sectors. Should be between 0 and 63(0 means auto)", |
| [ERR_SPECIFY_GEOM] = "Should not specify geometry when mapping a whole drive or when emulating a hard disk with a logical partition", |
| [ERR_EXTENDED_PARTITION] = "Extended partition table is invalid, or its CHS values conflict with the BPB in a logical partition", |
| [ERR_DEL_MEM_DRIVE] = "You should delete other mem drive first, or use `--mem' option to force the deletion", |
| [ERR_SPECIFY_MEM] = "Should not specify `--mem' when mapping a whole drive", |
| [ERR_INVALID_FLOPPIES] = "Invalid floppies. Should be between 0 and 2", |
| [ERR_INVALID_HARDDRIVES] = "Invalid harddrives. Should be between 0 and 127", |
| [ERR_INVALID_LOAD_SEGMENT] = "Invalid load segment. Should be between 0 and 0x9FFF", |
| [ERR_INVALID_LOAD_OFFSET] = "Invalid load offset. Should be between 0 and 0xFFFF", |
| [ERR_INVALID_LOAD_LENGTH] = "Invalid load length. Should be between 512 and 0xA0000", |
| [ERR_INVALID_SKIP_LENGTH] = "Invalid skip length. Should be non-negative and less than the file size", |
| [ERR_INVALID_BOOT_CS] = "Invalid boot CS. Should be between 0 and 0xFFFF", |
| [ERR_INVALID_BOOT_IP] = "Invalid boot IP. Should be between 0 and 0xFFFF", |
| [ERR_INVALID_RAM_DRIVE] = "Invalid ram_drive. Should be between 0 and 254", |
| // [ERR_INVALID_RD_BASE] = "Invalid rd_base. Should not be 0xffffffff", |
| // [ERR_INVALID_RD_SIZE] = "Invalid rd_size. Should not be 0", |
| [ERR_MD_BASE] = "When mapping whole mem device at a fixed location, you must specify --mem to a value > 0.", |
| [ERR_RD_BASE] = "RD_BASE must be sector-aligned and non-zero for mapping at a fixed location", |
| [ERR_DOS_BACKUP] = "GRUB was not booted from DOS, or the backup copy of DOS at physical\naddress 0x200000 is corrupt", |
| [ERR_ENABLE_A20] = "Failed to turn on Gate A20!", |
| [ERR_DISABLE_A20] = "Failed to turn off Gate A20!", |
| [ERR_DEFAULT_FILE] = "Invalid DEFAULT file format. Please copy a valid DEFAULT file from the grub4dos release and try again. Also note that the DEFAULT file must be uncompressed.", |
| [ERR_PARTITION_TABLE_FULL] = "Cannot use --in-situ because the partition table is full(i.e., all the 4 entries are in use).", |
| |
| }; |
| |
| |
| /* static for BIOS memory map fakery */ |
| static struct AddrRangeDesc fakemap[3] = |
| { |
| {20, 0, 0, MB_ARD_MEMORY}, |
| {20, 0x100000, 0, MB_ARD_MEMORY}, |
| {20, 0x1000000, 0, MB_ARD_MEMORY} |
| }; |
| |
| /* A big problem is that the memory areas aren't guaranteed to be: |
| (1) contiguous, (2) sorted in ascending order, or (3) non-overlapping. |
| Thus this kludge. */ |
| static unsigned long |
| mmap_avail_at (unsigned long bottom) |
| { |
| unsigned long long top; |
| unsigned long addr; |
| int cont; |
| |
| top = bottom; |
| do |
| { |
| for (cont = 0, addr = mbi.mmap_addr; |
| addr < mbi.mmap_addr + mbi.mmap_length; |
| addr += *((unsigned long *) addr) + 4) |
| { |
| struct AddrRangeDesc *desc = (struct AddrRangeDesc *) addr; |
| |
| if (desc->Type == MB_ARD_MEMORY |
| && desc->BaseAddr <= top |
| && desc->BaseAddr + desc->Length > top) |
| { |
| top = desc->BaseAddr + desc->Length; |
| cont++; |
| } |
| } |
| } |
| while (cont); |
| |
| /* For now, GRUB assumes 32bits addresses, so... */ |
| if (top > 0xFFFFFFFF) |
| top = 0xFFFFFFFF; |
| |
| return (unsigned long) top - bottom; |
| } |
| #endif /* ! STAGE1_5 */ |
| |
| /* This queries for BIOS information. */ |
| void |
| init_bios_info (void) |
| { |
| #ifndef STAGE1_5 |
| unsigned long cont, memtmp, addr; |
| int drive; |
| #endif |
| |
| /* |
| * Get information from BIOS on installed RAM. |
| */ |
| |
| mbi.mem_lower = get_memsize (0); /* int12 --------safe enough */ |
| mbi.mem_upper = get_memsize (1); /* int15/88 -----safe enough */ |
| |
| #ifndef STAGE1_5 |
| /* |
| * We need to call this somewhere before trying to put data |
| * above 1 MB, since without calling it, address line 20 will be wired |
| * to 0. Not too desirable. |
| */ |
| |
| #ifndef GRUB_UTIL |
| debug = 1; |
| printf("Turning on gate A20... "); |
| if (gateA20 (1)) /* int15/24 -----safe enough */ |
| printf("Success.\n"); |
| else |
| printf("Failure!\n"); |
| #endif |
| |
| /* Store the size of extended memory in EXTENDED_MEMORY, in order to |
| tell it to non-Multiboot OSes. */ |
| extended_memory = mbi.mem_upper; |
| |
| /* |
| * The "mbi.mem_upper" variable only recognizes upper memory in the |
| * first memory region. If there are multiple memory regions, |
| * the rest are reported to a Multiboot-compliant OS, but otherwise |
| * unused by GRUB. |
| */ |
| |
| addr = get_code_end (); |
| mbi.mmap_addr = addr; |
| mbi.mmap_length = 0; |
| cont = 0; |
| |
| do |
| { |
| cont = get_mmap_entry ((void *) addr, cont); /* int15/e820 ------ will write memory! */ |
| |
| /* If the returned buffer's length is zero, quit. */ |
| if (! *((unsigned long *) addr)) |
| break; |
| |
| mbi.mmap_length += *((unsigned long *) addr) + 4; |
| addr += *((unsigned long *) addr) + 4; |
| } |
| while (cont); |
| |
| if (mbi.mmap_length) |
| { |
| unsigned long long max_addr; |
| |
| /* |
| * This is to get the lower memory, and upper memory (up to the |
| * first memory hole), into the "mbi.mem_{lower,upper}" |
| * elements. This is for OS's that don't care about the memory |
| * map, but might care about total RAM available. |
| */ |
| mbi.mem_lower = mmap_avail_at (0) >> 10; |
| mbi.mem_upper = mmap_avail_at (0x100000) >> 10; |
| |
| /* Find the maximum available address. Ignore any memory holes. */ |
| for (max_addr = 0, addr = mbi.mmap_addr; |
| addr < mbi.mmap_addr + mbi.mmap_length; |
| addr += *((unsigned long *) addr) + 4) |
| { |
| struct AddrRangeDesc *desc = (struct AddrRangeDesc *) addr; |
| |
| if (desc->Type == MB_ARD_MEMORY && desc->Length > 0 |
| && desc->BaseAddr + desc->Length > max_addr) |
| max_addr = desc->BaseAddr + desc->Length; |
| } |
| |
| extended_memory = (max_addr - 0x100000) >> 10; |
| } |
| else if ((memtmp = get_eisamemsize ()) != -1) /* int15/e801 ------safe enough */ |
| { |
| cont = memtmp & ~0xFFFF; |
| memtmp = memtmp & 0xFFFF; |
| |
| if (cont != 0) |
| extended_memory = (cont >> 10) + 0x3c00; |
| else |
| extended_memory = memtmp; |
| |
| if (!cont || (memtmp == 0x3c00)) |
| memtmp += (cont >> 10); |
| else |
| { |
| /* XXX should I do this at all ??? */ |
| |
| mbi.mmap_addr = (unsigned long) fakemap; |
| mbi.mmap_length = sizeof (fakemap); |
| fakemap[0].Length = (mbi.mem_lower << 10); |
| fakemap[1].Length = (memtmp << 10); |
| fakemap[2].Length = cont; |
| } |
| |
| mbi.mem_upper = memtmp; |
| } |
| |
| saved_mem_upper = mbi.mem_upper; |
| |
| #ifndef GRUB_UTIL |
| is64bit = check_64bit (); |
| #endif |
| |
| /* Get the drive info. */ |
| /* FIXME: This should be postponed until a Multiboot kernel actually |
| requires it, because this could slow down the start-up |
| unreasonably. */ |
| mbi.drives_length = 0; |
| mbi.drives_addr = addr; |
| |
| /* For now, GRUB doesn't probe floppies, since it is trivial to map |
| floppy drives to BIOS drives. */ |
| #ifdef GRUB_UTIL |
| #define FIND_DRIVES 8 |
| #else |
| #define FIND_DRIVES (*((char *)0x475)) |
| #endif |
| if (debug) |
| grub_printf ("hard drives: %d, int13: %X, int15: %X\n", FIND_DRIVES, *(unsigned long *)0x4C, *(unsigned long *)0x54); |
| //#ifndef GRUB_UTIL |
| // FIND_DRIVES = 1; |
| //#endif |
| for (drive = 0x80; drive < 0x80 + FIND_DRIVES; drive++) |
| // for (drive = 0x80 + FIND_DRIVES - 1; drive >= 0x80; drive--) |
| { |
| #undef FIND_DRIVES |
| // struct geometry tmp_geom; |
| struct drive_info *info = (struct drive_info *) addr; |
| unsigned short *port; |
| |
| /* Get the geometry. This ensures that the drive is present. */ |
| if (debug) |
| grub_printf ("get_diskinfo(%X), ", drive); |
| if (get_diskinfo (drive, &tmp_geom)) |
| break; |
| if (debug) |
| grub_printf (" %sC/H/S=%d/%d/%d, Sector Count/Size=%d/%d\n", |
| (tmp_geom.flags & BIOSDISK_FLAG_LBA_EXTENSION) ? "LBA, " : "", |
| tmp_geom.cylinders, tmp_geom.heads, tmp_geom.sectors, |
| tmp_geom.total_sectors, tmp_geom.sector_size); |
| |
| /* Clean out the I/O map. */ |
| grub_memset ((char *) io_map, 0, |
| IO_MAP_SIZE * sizeof (unsigned short)); |
| |
| /* Disable to probe I/O ports temporarily, because this doesn't |
| work with some BIOSes (maybe they are too buggy). */ |
| #if 0 |
| /* Track the int13 handler. */ |
| track_int13 (drive); |
| #endif |
| |
| /* Set the information. */ |
| info->drive_number = drive; |
| info->drive_mode = ((tmp_geom.flags & BIOSDISK_FLAG_LBA_EXTENSION) |
| ? MB_DI_LBA_MODE : MB_DI_CHS_MODE); |
| info->drive_cylinders = tmp_geom.cylinders; |
| info->drive_heads = tmp_geom.heads; |
| info->drive_sectors = tmp_geom.sectors; |
| |
| addr += sizeof (struct drive_info); |
| for (port = io_map; *port; port++, addr += sizeof (unsigned short)) |
| *((unsigned short *) addr) = *port; |
| |
| info->size = addr - (unsigned long) info; |
| mbi.drives_length += info->size; |
| } |
| |
| /* Set the boot loader name. */ |
| mbi.boot_loader_name = (unsigned long) "GNU GRUB " VERSION; |
| |
| /* |
| * Initialize other Multiboot Info flags. |
| */ |
| |
| mbi.flags = (MB_INFO_MEMORY | MB_INFO_CMDLINE | MB_INFO_BOOTDEV |
| | MB_INFO_DRIVE_INFO | MB_INFO_CONFIG_TABLE |
| | MB_INFO_BOOT_LOADER_NAME); |
| |
| #if 0 |
| |
| /* Only multi_boot need this. So we should not initialize it here. |
| * Moved to boot_func in builtins.c |
| */ |
| |
| /* Get the ROM configuration table by INT 15, AH=C0h. */ |
| mbi.config_table = get_rom_config_table (); |
| |
| /* Get the APM BIOS table. */ |
| get_apm_info (); |
| if (apm_bios_info.version) |
| mbi.apm_table = (unsigned long) &apm_bios_info; |
| |
| if (apm_bios_info.version) |
| mbi.flags |= MB_INFO_APM_TABLE; |
| |
| #endif |
| |
| #endif /* STAGE1_5 */ |
| |
| #if !defined(STAGE1_5) && !defined(GRUB_UTIL) |
| /* Set cdrom drive. */ |
| |
| //#if 0 |
| // /* Get the geometry. */ |
| // if (get_diskinfo (boot_drive, &tmp_geom) |
| // || ! (geom.flags & BIOSDISK_FLAG_CDROM)) |
| // cdrom_drive = GRUB_INVALID_DRIVE; |
| // else |
| // cdrom_drive = boot_drive; |
| //#else |
| /* Get the geometry. */ |
| if (debug) |
| printf("boot drive=%X, ", boot_drive); |
| cdrom_drive = get_cdinfo (boot_drive, &tmp_geom); |
| if (! cdrom_drive || cdrom_drive != boot_drive) |
| cdrom_drive = GRUB_INVALID_DRIVE; |
| if (debug) |
| printf("%s\n", cdrom_drive == GRUB_INVALID_DRIVE ? "Not CD":"Is CD"); |
| //#endif |
| #endif |
| |
| #if !defined(STAGE1_5) && !defined(GRUB_UTIL) |
| |
| if (cdrom_drive == GRUB_INVALID_DRIVE) |
| { |
| int err; |
| int version; |
| struct drive_parameters *drp = (struct drive_parameters *)0x600; |
| |
| #ifdef GRUB_UTIL |
| #define FIND_DRIVES 8 |
| #else |
| #define FIND_DRIVES (*((char *)0x475)) |
| #endif |
| for (drive = 0x7F; drive < 0xff; drive++) |
| { |
| // struct geometry tmp_geom; |
| |
| if (drive >= 0x80 && drive < 0x80 + FIND_DRIVES) |
| continue; |
| |
| /* Get the geometry. */ |
| if (debug) |
| grub_printf ("\rget_cdinfo(%X),", drive); |
| cdrom_drive = get_cdinfo (drive, &tmp_geom); |
| // if (debug) |
| // grub_printf ("cdrom_drive=%X", cdrom_drive); |
| if (cdrom_drive) |
| break; |
| |
| cdrom_drive = GRUB_INVALID_DRIVE; |
| |
| /* Some buggy BIOSes will hang at EBIOS `Get Drive Parameters' call |
| * (INT 13h function 48h). So we only do further checks for Bochs. |
| */ |
| |
| if (bios_id != 1) /* if it is not Bochs ... */ |
| continue; /* ... skip and try next drive. */ |
| |
| /* When qemu has a cdrom attached but not booted from cdrom, its |
| * `get bootable cdrom status call', the int13/ax=4B01, returns CF=0 |
| * but with a wrong `Bootable CD-ROM Specification Packet' as follows: |
| * |
| * The first byte(packet size) is 0x13, all the rest bytes are 0's. |
| * |
| * So we need to call get_diskinfo() here as a workaround. |
| * |
| * (The bug was reported by Jacopo Lazzari. Thanks!) |
| */ |
| |
| if (drive >= 0x80) |
| { |
| //printf("check drive: 0x%X\t\t", drive); |
| |
| //printf (" check_int13_extensions (0x%X) ...", drive); |
| version = check_int13_extensions (drive); |
| //printf (" OK! version=0x%X\n", version); |
| |
| if (! (version & 1)) /* not support functions 42h-44h, 47h-48h */ |
| continue; /* failure, try next drive. */ |
| |
| /* PhoenixBIOS 4.0 Revision 6.0 for ZF Micro might understand |
| the greater buffer size for the "get drive parameters" int |
| 0x13 call in its own way. Supposedly the BIOS assumes even |
| bigger space is available and thus corrupts the stack. |
| This is why we specify the exactly necessary size of 0x42 |
| bytes. */ |
| |
| /* It is safe to clear out DRP. */ |
| grub_memset (drp, 0, sizeof (struct drive_parameters)); |
| |
| drp->size = sizeof (struct drive_parameters) - 16; |
| |
| //printf (" biosdisk_int13_extensions (0x4800, 0x%X) ...", drive); |
| err = biosdisk_int13_extensions (0x4800, drive, drp); |
| //printf (" OK! err=0x%X\n", err); |
| if (! err && drp->bytes_per_sector == ISO_SECTOR_SIZE) |
| { |
| /* Assume it is CDROM. */ |
| cdrom_drive = drive; |
| break; |
| } |
| //printf("not cdrom\r", drive); |
| } /* if (drive >= 0x80) */ |
| |
| } /* for (drive = 0x7F; drive < 0xff; drive++) */ |
| } /* if (cdrom_drive == GRUB_INVALID_DRIVE) */ |
| #undef FIND_DRIVES |
| |
| if (debug) |
| grub_printf(" cdrom_drive == %X.\n", cdrom_drive); |
| #endif /* ! STAGE1_5 && ! GRUB_UTIL */ |
| |
| /* check if the no-emulation-mode bootable cdrom exists. */ |
| |
| /* if cdrom_drive is active, we assume it is the boot device */ |
| if (saved_entryno == 0 && force_cdrom_as_boot_device) |
| force_cdrom_as_boot_device = 0; |
| if (cdrom_drive != GRUB_INVALID_DRIVE && force_cdrom_as_boot_device) |
| { |
| boot_drive = cdrom_drive; /* force it to be the boot drive */ |
| } |
| |
| if (boot_drive == cdrom_drive) |
| /* force it to be "whole drive" without partition table */ |
| install_partition = 0xFFFFFF; |
| |
| /* Set boot drive and partition. */ |
| saved_drive = boot_drive; |
| saved_partition = install_partition; |
| |
| #ifndef GRUB_UTIL |
| #ifndef STAGE1_5 |
| debug = 0; |
| #if 0 |
| if (cdrom_drive == GRUB_INVALID_DRIVE) |
| { |
| min_cdrom_id = 0xE0; |
| }else{ |
| min_cdrom_id = cdrom_drive <= 0xE0 ? cdrom_drive + 1 : cdrom_drive - 0x20; |
| } |
| #else |
| min_cdrom_id = (cdrom_drive < 0xE0 && cdrom_drive >= 0xC0) ? 0xE0 : 0xC0; |
| //min_cdrom_id = 0xC0 | ((cdrom_drive < 0xE0) << 5); |
| #endif |
| |
| /* if grub.exe is booted as a Linux kernel, check the initrd disk. */ |
| |
| /* the real mode zero page(only the beginning 2 sectors, the boot params) is loaded at 0xA00 */ |
| |
| /* check the header signature "HdrS" (0x53726448) */ |
| |
| ram_drive = 0x7f; /* the default ram_drive is a floppy. */ |
| if (*(unsigned long*)(int*)(0xA00 + 0x202) == 0x53726448) |
| { |
| unsigned long initrd_addr; |
| unsigned long initrd_size; |
| |
| initrd_addr = *(unsigned long*)(int*)(0xA00 + 0x218); |
| initrd_size = *(unsigned long*)(int*)(0xA00 + 0x21c); |
| if (initrd_addr && initrd_size) |
| { |
| rd_base = initrd_addr; |
| rd_size = initrd_size; |
| |
| /* check if there is a partition table */ |
| if (*(unsigned short *)(initrd_addr + 0x40) == 0xAA55) |
| { |
| #if 0 |
| initrd_addr += 0x1BE; /* here begins the partition table */ |
| initrd_size = 0; /* count valid partition entries */ |
| |
| for (i = 0; i < 4; i++) |
| { |
| if ((unsigned char)(*(char*)(initrd_addr + i*16) & 0x7F)) |
| break; |
| if ((*(long long *)(initrd_addr + i*16)) | (*(long long *)(initrd_addr + i*16 + 8))) |
| { |
| if (! (*(long *)(initrd_addr + i*16 + 8)) || ! (*(long long *)(initrd_addr + i*16 + 12))) |
| break; |
| if (! (*(char *)(initrd_addr + i*16 + 2)) & 0x3f) |
| break; |
| if (! (*(char *)(initrd_addr + i*16 + 6)) & 0x3f) |
| break; |
| initrd_size++; |
| } |
| } |
| |
| if (i == 4 && initrd_size) /* partition table is valid. */ |
| ram_drive = 0xfe; /* let it be a harddrive */ |
| #else |
| if (! probe_mbr ((struct master_and_dos_boot_sector *)initrd_addr, 0, initrd_size, 0)) |
| ram_drive = 0xfe; /* partition table is valid, so let it be a harddrive */ |
| else |
| grub_printf ("\nUnrecognized partition table for RAM DRIVE; assuming floppy. Please rebuild\nit using a Microsoft-compatible FDISK tool, if the INITRD is a hard-disk image.\n"); |
| #endif |
| } |
| } |
| } |
| #endif /* ! STAGE1_5 */ |
| #endif /* ! GRUB_UTIL */ |
| |
| /* Start main routine here. */ |
| |
| grub_printf("Starting cmain() ... "); |
| |
| cmain (); |
| } |