tablet/grub
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

disk/i386/pc/biosdisk: Read up to 63 sectors in LBA mode

Browse Source 
Current code imposes limitations on the amount of sectors read in
a single call according to CHS layout of the disk even in LBA
read mode. There's no need to obey CHS layout restrictions for
LBA reads on LBA disks. It only slows down booting process.

See: https://lore.kernel.org/grub-devel/d42a11fa-2a59-b5e7-08b1-d2c60444bb99@valdikss.org.ru/

Signed-off-by: ValdikSS <iam@valdikss.org.ru>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
ValdikSS 2023-10-10 21:28:44 +03:00 committed by Daniel Kiper
parent cab04dcda3
commit 4266fd2bb2
2 changed files with 7 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
grub-core/disk/i386/pc/biosdisk.c
View File

@ -471,7 +471,7 @@ grub_biosdisk_rw (int cmd, grub_disk_t disk,
struct grub_biosdisk_dap *dap;
dap = (struct grub_biosdisk_dap *) (GRUB_MEMORY_MACHINE_SCRATCH_ADDR
+ (data->sectors
+ (GRUB_DISK_MAX_LBA_SECTORS
<< disk->log_sector_size));
dap->length = sizeof (*dap);
dap->reserved = 0;
@ -561,6 +561,9 @@ get_safe_sectors (grub_disk_t disk, grub_disk_addr_t sector)
struct grub_biosdisk_data *data = disk->data;
grub_uint32_t sectors = data->sectors;
if (data->flags & GRUB_BIOSDISK_FLAG_LBA)
sectors = GRUB_DISK_MAX_LBA_SECTORS;
/* OFFSET = SECTOR % SECTORS */
grub_divmod64 (sector, sectors, &offset);

3
include/grub/disk.h
View File

@ -190,6 +190,9 @@ typedef struct grub_disk_memberlist *grub_disk_memberlist_t;
#define GRUB_DISK_MAX_MAX_AGGLOMERATE ((1 << (30 - GRUB_DISK_CACHE_BITS - GRUB_DISK_SECTOR_BITS)) - 1)
/* Maximum number of sectors to read in LBA mode at once. */
#define GRUB_DISK_MAX_LBA_SECTORS 63
/* Return value of grub_disk_native_sectors() in case disk size is unknown. */
#define GRUB_DISK_SIZE_UNKNOWN 0xffffffffffffffffULL