From c0d00403a297d6023eab6189ba87dc8a3f6d1e85 Mon Sep 17 00:00:00 2001 From: Michael Chang Date: Mon, 7 Feb 2022 20:44:40 +0800 Subject: [PATCH 2/5] Add grub_disk_write_tail helper function This helps in writing data to partition where the end of buffer is aligned to end of partition. Signed-off-by: Michael Chang --- grub-core/lib/disk.c | 18 ++++++++++++++++++ include/grub/disk.h | 3 +++ 2 files changed, 21 insertions(+) diff --git a/grub-core/lib/disk.c b/grub-core/lib/disk.c index b4eb064a81..08e24485f0 100644 --- a/grub-core/lib/disk.c +++ b/grub-core/lib/disk.c @@ -51,6 +51,24 @@ grub_disk_cache_invalidate (unsigned long dev_id, unsigned long disk_id, } } +grub_err_t +grub_disk_write_tail (grub_disk_t disk, grub_size_t size, const void *buf) +{ + grub_partition_t part; + grub_disk_addr_t sector; + grub_off_t offset; + + if (!disk->partition) + return GRUB_ERR_NONE; + + part = disk->partition; + sector = part->len; + sector -= (size + GRUB_DISK_SECTOR_SIZE - 1) >> GRUB_DISK_SECTOR_BITS; + offset = size & (GRUB_DISK_SECTOR_SIZE - 1); + + return grub_disk_write (disk, sector, offset, size, buf); +} + grub_err_t grub_disk_write (grub_disk_t disk, grub_disk_addr_t sector, grub_off_t offset, grub_size_t size, const void *buf) diff --git a/include/grub/disk.h b/include/grub/disk.h index f95aca929a..6d656c4315 100644 --- a/include/grub/disk.h +++ b/include/grub/disk.h @@ -232,6 +232,9 @@ grub_err_t EXPORT_FUNC(grub_disk_read) (grub_disk_t disk, grub_off_t offset, grub_size_t size, void *buf); +grub_err_t grub_disk_write_tail (grub_disk_t disk, + grub_size_t size, + const void *buf); grub_err_t grub_disk_write (grub_disk_t disk, grub_disk_addr_t sector, grub_off_t offset, -- 2.34.1