static int
grub_biosdisk_iterate (int (*hook) (const char *name))
{
int drive;
int num_floppies;
/* For hard disks, attempt to read the MBR. */
for (drive = 0x80; drive < 0x90; drive++)
{
if (grub_biosdisk_rw_standard (0x02, drive, 0, 0, 1, 1,
GRUB_MEMORY_MACHINE_SCRATCH_SEG) != 0)
{
grub_dprintf ("disk", "Read error when probing drive 0x%2x\n", drive);
break;
}
if (grub_biosdisk_call_hook (hook, drive))
return 1;
}
if (cd_drive)
{
if (grub_biosdisk_call_hook (hook, cd_drive))
return 1;
}
/* For floppy disks, we can get the number safely. */
num_floppies = grub_biosdisk_get_num_floppies ();
for (drive = 0; drive < num_floppies; drive++)
if (grub_biosdisk_call_hook (hook, drive))
return 1;
return 0;
}
static struct grub_biosdisk_data *
get_drive_geom (int drive)
{
int i;
struct grub_biosdisk_data *data = grub_biosdisk_geom;
grub_uint64_t total_sectors = 0;
unsigned long cylinders;
int is_fb = 0;
struct fb_mbr *m;
for (i = 0; i < grub_biosdisk_num; i++, data++)
if (data->drive == drive)
return data;
m = (struct fb_mbr *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
if (drive != cd_drive)
{
if (grub_biosdisk_rw_standard (0x02, drive, 0, 0, 1, 1,
GRUB_MEMORY_MACHINE_SCRATCH_SEG) != 0)
return 0;
is_fb = ((m->fb_magic == FB_MAGIC_LONG) && (m->end_magic == 0xaa55));
}
else
is_fb = 0;
if ((grub_biosdisk_num & (DISK_NUM_INC - 1)) == 0)
{
grub_biosdisk_geom = grub_realloc (grub_biosdisk_geom,
(grub_biosdisk_num + DISK_NUM_INC) *
sizeof (*data));
if (! grub_biosdisk_geom)
return 0;
}
data = &grub_biosdisk_geom[grub_biosdisk_num++];
grub_memset (data, 0, sizeof (*data));
data->drive = drive;
if (drive == cd_drive)
{
data->flags = GRUB_BIOSDISK_FLAG_LBA | GRUB_BIOSDISK_FLAG_CDROM;
data->max_sectors = data->sectors = 32;
data->total_sectors = GRUB_ULONG_MAX; /* TODO: get the correct size. */
return data;
}
if (drive & 0x80)
{
/* HDD */
int version;
version = grub_biosdisk_check_int13_extensions (drive);
if (version)
{
struct grub_biosdisk_drp *drp
= (struct grub_biosdisk_drp *)
(GRUB_MEMORY_MACHINE_SCRATCH_ADDR + 512);
/* Clear out the DRP. */
grub_memset (drp, 0, sizeof (*drp));
drp->size = sizeof (*drp);
if (! grub_biosdisk_get_diskinfo_int13_extensions (drive, drp))
{
data->flags = GRUB_BIOSDISK_FLAG_LBA;
if (drp->cylinders == 65535)
total_sectors = GRUB_ULONG_MAX;
else if (drp->total_sectors)
total_sectors = drp->total_sectors;
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;
}
}
data->sectors = 63;
data->heads = 255;
cylinders = 0;
grub_biosdisk_get_diskinfo_standard (drive, &cylinders,
&data->heads, &data->sectors);
}
else
{
grub_uint16_t t;
t = *((grub_uint16_t *) (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + 0x18));
data->sectors = ((t > 0) && (t <= 63)) ? t : 18;
t = *((grub_uint16_t *) (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + 0x1a));
data->heads = ((t > 0) && (t <= 255)) ? t : 2;
cylinders = 1024;
}
data->max_sectors = 63;
if (is_fb)
{
grub_uint16_t ofs = m->lba;
data->max_sectors = m->max_sec;
if (data->max_sectors >= 0x80)
{
data->max_sectors &= 0x7f;
data->flags &= ~GRUB_BIOSDISK_FLAG_LBA;
}
if (! (data->flags & GRUB_BIOSDISK_FLAG_LBA))
{
grub_uint16_t lba;
if (grub_biosdisk_rw_standard (0x02, drive,
0, 1, 1, 1,
GRUB_MEMORY_MACHINE_SCRATCH_SEG))
goto next;
lba = m->end_magic;
if (lba == 0xaa55)
{
if (m->fb_magic != FB_MAGIC_LONG)
goto next;
else
lba = m->lba;
}
data->sectors = lba - ofs;
if (grub_biosdisk_rw_standard (0x02, drive,
1, 0, 1, 1,
GRUB_MEMORY_MACHINE_SCRATCH_SEG))
goto next;
lba = m->end_magic;
if (lba == 0xaa55)
goto next;
data->heads = (lba - ofs) / data->sectors;
}
data->flags |= GRUB_BIOSDISK_FLAG_FB;
}
if ((data->flags & GRUB_BIOSDISK_FLAG_LBA) &&
(data->max_sectors == 63))
data->max_sectors = GRUB_BIOSDISK_MAX_SECTORS;
next:
cylinders *= data->heads * data->sectors;
if (total_sectors < cylinders)
total_sectors = cylinders;
data->total_sectors = total_sectors;
return data;
}