Commit 771aba0d authored by David Sterba's avatar David Sterba
Browse files

btrfs: scrub: simplify data block checksum calculation 



We have sectorsize same as PAGE_SIZE, the checksum can be calculated in
one go.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent c7460541

fs/btrfs/scrub.c

+3 −21
Original line number Diff line number Diff line
@@ -1789,37 +1789,19 @@ static int scrub_checksum_data(struct scrub_block *sblock) 
	u8 *on_disk_csum;

	struct page *page;

	char *kaddr;

	u64 len;

	int index;



	BUG_ON(sblock->page_count < 1);

	if (!sblock->pagev[0]->have_csum)

		return 0;



	shash->tfm = fs_info->csum_shash;

	crypto_shash_init(shash);



	on_disk_csum = sblock->pagev[0]->csum;

	page = sblock->pagev[0]->page;

	kaddr = page_address(page);



	len = sctx->fs_info->sectorsize;

	index = 0;

	for (;;) {

		u64 l = min_t(u64, len, PAGE_SIZE);



		crypto_shash_update(shash, kaddr, l);

		len -= l;

		if (len == 0)

			break;

		index++;

		BUG_ON(index >= sblock->page_count);

		BUG_ON(!sblock->pagev[index]->page);

		page = sblock->pagev[index]->page;

		kaddr = page_address(page);

	}

	shash->tfm = fs_info->csum_shash;

	crypto_shash_init(shash);

	crypto_shash_digest(shash, kaddr, PAGE_SIZE, csum);



	crypto_shash_final(shash, csum);

	if (memcmp(csum, on_disk_csum, sctx->csum_size))

		sblock->checksum_error = 1;