/* * PUPA -- Preliminary Universal Programming Architecture for GRUB * Copyright (C) 1999,2000,2001,2002,2003 Free Software Foundation, Inc. * * PUPA 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 PUPA; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include #include #include #include #include #include /* Drive Parameters. */ struct pupa_biosdisk_drp { pupa_uint16_t size; pupa_uint16_t flags; pupa_uint32_t cylinders; pupa_uint32_t heads; pupa_uint32_t sectors; pupa_uint64_t total_sectors; pupa_uint16_t bytes_per_sector; /* ver 2.0 or higher */ pupa_uint32_t EDD_configuration_parameters; /* ver 3.0 or higher */ pupa_uint16_t signature_dpi; pupa_uint8_t length_dpi; pupa_uint8_t reserved[3]; pupa_uint8_t name_of_host_bus[4]; pupa_uint8_t name_of_interface_type[8]; pupa_uint8_t interface_path[8]; pupa_uint8_t device_path[8]; pupa_uint8_t reserved2; pupa_uint8_t checksum; /* XXX: This is necessary, because the BIOS of Thinkpad X20 writes a garbage to the tail of drive parameters, regardless of a size specified in a caller. */ pupa_uint8_t dummy[16]; } __attribute__ ((packed)); /* Disk Address Packet. */ struct pupa_biosdisk_dap { pupa_uint8_t length; pupa_uint8_t reserved; pupa_uint16_t blocks; pupa_uint32_t buffer; pupa_uint64_t block; } __attribute__ ((packed)); static int pupa_biosdisk_get_drive (const char *name) { unsigned long drive; if ((name[0] != 'f' && name[0] != 'h') || name[1] != 'd') goto fail; drive = pupa_strtoul (name + 2, 0, 10); if (pupa_errno != PUPA_ERR_NONE) goto fail; if (name[0] == 'h') drive += 0x80; return (int) drive ; fail: pupa_error (PUPA_ERR_UNKNOWN_DEVICE, "not a biosdisk"); return -1; } static int pupa_biosdisk_call_hook (int (*hook) (const char *name), int drive) { char name[10]; pupa_sprintf (name, (drive & 0x80) ? "hd%d" : "fd%d", drive & (~0x80)); return hook (name); } static int pupa_biosdisk_iterate (int (*hook) (const char *name)) { int drive; int num_floppies; /* For floppy disks, we can get the number safely. */ num_floppies = pupa_biosdisk_get_num_floppies (); for (drive = 0; drive < num_floppies; drive++) if (pupa_biosdisk_call_hook (hook, drive)) return 1; /* For hard disks, attempt to read the MBR. */ for (drive = 0x80; drive < 0x90; drive++) { if (pupa_biosdisk_rw_standard (0x02, drive, 0, 0, 1, 1, PUPA_MEMORY_MACHINE_SCRATCH_SEG) != 0) break; if (pupa_biosdisk_call_hook (hook, drive)) return 1; } return 0; } static pupa_err_t pupa_biosdisk_open (const char *name, pupa_disk_t disk) { unsigned long total_sectors = 0; int drive; struct pupa_biosdisk_data *data; drive = pupa_biosdisk_get_drive (name); if (drive < 0) return pupa_errno; disk->has_partitions = (drive & 0x80); disk->id = drive; data = (struct pupa_biosdisk_data *) pupa_malloc (sizeof (*data)); if (! data) return pupa_errno; data->drive = drive; data->flags = 0; if (drive & 0x80) { /* HDD */ int version; version = pupa_biosdisk_check_int13_extensions (drive); if (version) { struct pupa_biosdisk_drp *drp = (struct pupa_biosdisk_drp *) PUPA_MEMORY_MACHINE_SCRATCH_ADDR; /* Clear out the DRP. */ pupa_memset (drp, 0, sizeof (*drp)); drp->size = sizeof (*drp); if (!pupa_biosdisk_get_diskinfo_int13_extensions (drive, drp)) { data->flags = PUPA_BIOSDISK_FLAG_LBA; /* FIXME: 2TB limit. */ if (drp->total_sectors) total_sectors = drp->total_sectors & ~0L; else /* Some buggy BIOSes doesn't return the total sectors correctly but returns zero. So if it is zero, compute it by C/H/S returned by the LBA BIOS call. */ total_sectors = drp->cylinders * drp->heads * drp->sectors; } } } if (pupa_biosdisk_get_diskinfo_standard (drive, &data->cylinders, &data->heads, &data->sectors) != 0) { pupa_free (data); return pupa_error (PUPA_ERR_BAD_DEVICE, "cannot get C/H/S values"); } if (! total_sectors) total_sectors = data->cylinders * data->heads * data->sectors; disk->total_sectors = total_sectors; disk->data = data; return PUPA_ERR_NONE; } static void pupa_biosdisk_close (pupa_disk_t disk) { pupa_free (disk->data); } /* For readability. */ #define PUPA_BIOSDISK_READ 0 #define PUPA_BIOSDISK_WRITE 1 static pupa_err_t pupa_biosdisk_rw (int cmd, pupa_disk_t disk, unsigned long sector, unsigned long size, unsigned segment) { struct pupa_biosdisk_data *data = disk->data; if (data->flags & PUPA_BIOSDISK_FLAG_LBA) { struct pupa_biosdisk_dap *dap; dap = (struct pupa_biosdisk_dap *) (PUPA_MEMORY_MACHINE_SCRATCH_ADDR + (data->sectors << PUPA_DISK_SECTOR_BITS)); dap->length = sizeof (*dap); dap->reserved = 0; dap->blocks = size; dap->buffer = segment << 16; /* The format SEGMENT:ADDRESS. */ dap->block = sector; if (pupa_biosdisk_rw_int13_extensions (cmd + 0x42, data->drive, dap)) { /* Fall back to the CHS mode. */ data->flags &= ~PUPA_BIOSDISK_FLAG_LBA; disk->total_sectors = data->cylinders * data->heads * data->sectors; return pupa_biosdisk_rw (cmd, disk, sector, size, segment); } } else { unsigned coff, hoff, soff; unsigned head; soff = sector % data->sectors + 1; head = sector / data->sectors; hoff = head % data->heads; coff = head / data->heads; if (coff >= data->cylinders) return pupa_error (PUPA_ERR_OUT_OF_RANGE, "out of disk"); if (pupa_biosdisk_rw_standard (cmd + 0x02, data->drive, coff, hoff, soff, size, segment)) { switch (cmd) { case PUPA_BIOSDISK_READ: return pupa_error (PUPA_ERR_READ_ERROR, "biosdisk read error"); case PUPA_BIOSDISK_WRITE: return pupa_error (PUPA_ERR_WRITE_ERROR, "biosdisk write error"); } } } return PUPA_ERR_NONE; } static pupa_err_t pupa_biosdisk_read (pupa_disk_t disk, unsigned long sector, unsigned long size, char *buf) { struct pupa_biosdisk_data *data = disk->data; while (size) { unsigned long len; len = data->sectors - (sector % data->sectors); if (len > size) len = size; if (pupa_biosdisk_rw (PUPA_BIOSDISK_READ, disk, sector, len, PUPA_MEMORY_MACHINE_SCRATCH_SEG)) return pupa_errno; pupa_memcpy (buf, (void *) PUPA_MEMORY_MACHINE_SCRATCH_ADDR, len << PUPA_DISK_SECTOR_BITS); buf += len << PUPA_DISK_SECTOR_BITS; sector += len; size -= len; } return pupa_errno; } static pupa_err_t pupa_biosdisk_write (pupa_disk_t disk, unsigned long sector, unsigned long size, const char *buf) { struct pupa_biosdisk_data *data = disk->data; while (size) { unsigned long len; len = data->sectors - (sector % data->sectors); if (len > size) len = size; pupa_memcpy ((void *) PUPA_MEMORY_MACHINE_SCRATCH_ADDR, buf, len << PUPA_DISK_SECTOR_BITS); if (pupa_biosdisk_rw (PUPA_BIOSDISK_WRITE, disk, sector, len, PUPA_MEMORY_MACHINE_SCRATCH_SEG)) return pupa_errno; buf += len << PUPA_DISK_SECTOR_BITS; sector += len; size -= len; } return pupa_errno; } static struct pupa_disk_dev pupa_biosdisk_dev = { .name = "biosdisk", .iterate = pupa_biosdisk_iterate, .open = pupa_biosdisk_open, .close = pupa_biosdisk_close, .read = pupa_biosdisk_read, .write = pupa_biosdisk_write, .next = 0 }; void pupa_biosdisk_init (void) { pupa_disk_dev_register (&pupa_biosdisk_dev); }