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Initial variable sector size support

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This commit is contained in:
Vladimir 'phcoder' Serbinenko 2011-03-29 02:02:55 +02:00
parent f329eda79e
commit 09573499ff
7 changed files with 155 additions and 96 deletions
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52
grub-core/disk/i386/pc/biosdisk.c
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@ -338,7 +338,8 @@ grub_biosdisk_open (const char *name, grub_disk_t disk)
if ((cd_drive) && (drive == cd_drive))
{
data->flags = GRUB_BIOSDISK_FLAG_LBA | GRUB_BIOSDISK_FLAG_CDROM;
data->sectors = 32;
data->sectors = 8;
disk->log_sector_size = 11;
/* TODO: get the correct size. */
total_sectors = GRUB_DISK_SIZE_UNKNOWN;
}
@ -347,6 +348,8 @@ grub_biosdisk_open (const char *name, grub_disk_t disk)
/* HDD */
int version;
disk->log_sector_size = 9;
version = grub_biosdisk_check_int13_extensions (drive);
if (version)
{
@ -367,6 +370,15 @@ grub_biosdisk_open (const char *name, grub_disk_t disk)
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 (drp->bytes_per_sector
&& !(drp->bytes_per_sector & (drp->bytes_per_sector - 1))
&& drp->bytes_per_sector >= 512
&& drp->bytes_per_sector <= 16384)
{
for (disk->log_sector_size = 0;
(1 << disk->log_sector_size) < drp->bytes_per_sector;
disk->log_sector_size++);
}
}
}
}
@ -429,7 +441,7 @@ grub_biosdisk_rw (int cmd, grub_disk_t disk,
dap = (struct grub_biosdisk_dap *) (GRUB_MEMORY_MACHINE_SCRATCH_ADDR
+ (data->sectors
<< GRUB_DISK_SECTOR_BITS));
<< disk->log_sector_size));
dap->length = sizeof (*dap);
dap->reserved = 0;
dap->blocks = size;
@ -443,9 +455,6 @@ grub_biosdisk_rw (int cmd, grub_disk_t disk,
if (cmd)
return grub_error (GRUB_ERR_WRITE_ERROR, "can\'t write to cdrom");
dap->blocks = ALIGN_UP (dap->blocks, 4) >> 2;
dap->block >>= 2;
for (i = 0; i < GRUB_BIOSDISK_CDROM_RETRY_COUNT; i++)
if (! grub_biosdisk_rw_int13_extensions (0x42, data->drive, dap))
break;
@ -501,10 +510,12 @@ grub_biosdisk_rw (int cmd, grub_disk_t disk,
/* Return the number of sectors which can be read safely at a time. */
static grub_size_t
get_safe_sectors (grub_disk_addr_t sector, grub_uint32_t sectors)
get_safe_sectors (grub_disk_t disk, grub_disk_addr_t sector)
{
grub_size_t size;
grub_uint32_t offset;
struct grub_biosdisk_data *data = disk->data;
grub_uint32_t sectors = data->sectors;
/* OFFSET = SECTOR % SECTORS */
grub_divmod64 (sector, sectors, &offset);
@ -512,8 +523,8 @@ get_safe_sectors (grub_disk_addr_t sector, grub_uint32_t sectors)
size = sectors - offset;
/* Limit the max to 0x7f because of Phoenix EDD. */
if (size > 0x7f)
size = 0x7f;
if (size > ((0x7fU << GRUB_DISK_SECTOR_BITS) >> disk->log_sector_size))
size = ((0x7fU << GRUB_DISK_SECTOR_BITS) >> disk->log_sector_size);
return size;
}
@ -522,21 +533,11 @@ static grub_err_t
grub_biosdisk_read (grub_disk_t disk, grub_disk_addr_t sector,
grub_size_t size, char *buf)
{
struct grub_biosdisk_data *data = disk->data;
while (size)
{
grub_size_t len;
grub_size_t cdoff = 0;
len = get_safe_sectors (sector, data->sectors);
if (data->flags & GRUB_BIOSDISK_FLAG_CDROM)
{
cdoff = (sector & 3) << GRUB_DISK_SECTOR_BITS;
len = ALIGN_UP (sector + len, 4) - (sector & ~3);
sector &= ~3;
}
len = get_safe_sectors (disk, sector);
if (len > size)
len = size;
@ -545,9 +546,10 @@ grub_biosdisk_read (grub_disk_t disk, grub_disk_addr_t sector,
GRUB_MEMORY_MACHINE_SCRATCH_SEG))
return grub_errno;
grub_memcpy (buf, (void *) (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + cdoff),
len << GRUB_DISK_SECTOR_BITS);
buf += len << GRUB_DISK_SECTOR_BITS;
grub_memcpy (buf, (void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR,
len << disk->log_sector_size);
buf += len << disk->log_sector_size;
sector += len;
size -= len;
}
@ -568,18 +570,18 @@ grub_biosdisk_write (grub_disk_t disk, grub_disk_addr_t sector,
{
grub_size_t len;
len = get_safe_sectors (sector, data->sectors);
len = get_safe_sectors (disk, sector);
if (len > size)
len = size;
grub_memcpy ((void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR, buf,
len << GRUB_DISK_SECTOR_BITS);
len << disk->log_sector_size);
if (grub_biosdisk_rw (GRUB_BIOSDISK_WRITE, disk, sector, len,
GRUB_MEMORY_MACHINE_SCRATCH_SEG))
return grub_errno;
buf += len << GRUB_DISK_SECTOR_BITS;
buf += len << disk->log_sector_size;
sector += len;
size -= len;
}