Commit 265d4ac0 authored by Qu Wenruo's avatar Qu Wenruo Committed by David Sterba
Browse files

btrfs: sink parameter start and len to check_data_csum 



For check_data_csum(), the page we're using is directly from the inode
mapping, thus it has valid page_offset().

We can use (page_offset() + pg_off) to replace @start parameter
completely, while the @len should always be sectorsize.

Since we're here, also add some comment, as there are quite some
confusion in words like start/offset, without explaining whether it's
file_offset or logical bytenr.

This should not affect the existing behavior, as for current sectorsize
== PAGE_SIZE case, @pgoff should always be 0, and len is always
PAGE_SIZE (or sectorsize from the dio read path).

Reviewed-by: default avatarGoldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: default avatarQu Wenruo <wqu@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 8896a08d

fs/btrfs/inode.c

+18 −8
Original line number Diff line number Diff line
@@ -2889,17 +2889,29 @@ void btrfs_writepage_endio_finish_ordered(struct page *page, u64 start, 
	btrfs_queue_work(wq, &ordered_extent->work);

}



/*

 * check_data_csum - verify checksum of one sector of uncompressed data

 * @inode:	the inode

 * @io_bio:	btrfs_io_bio which contains the csum

 * @icsum:	checksum index in the io_bio->csum array, size of csum_size

 * @page:	page where is the data to be verified

 * @pgoff:	offset inside the page

 *

 * The length of such check is always one sector size.

 */

static int check_data_csum(struct inode *inode, struct btrfs_io_bio *io_bio,

			   int icsum, struct page *page, int pgoff, u64 start,

			   size_t len)

			   int icsum, struct page *page, int pgoff)

{

	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);

	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);

	char *kaddr;

	u32 len = fs_info->sectorsize;

	u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);

	u8 *csum_expected;

	u8 csum[BTRFS_CSUM_SIZE];



	ASSERT(pgoff + len <= PAGE_SIZE);



	csum_expected = ((u8 *)io_bio->csum) + icsum * csum_size;



	kaddr = kmap_atomic(page);
@@ -2913,8 +2925,8 @@ static int check_data_csum(struct inode *inode, struct btrfs_io_bio *io_bio, 
	kunmap_atomic(kaddr);

	return 0;

zeroit:

	btrfs_print_data_csum_error(BTRFS_I(inode), start, csum, csum_expected,

				    io_bio->mirror_num);

	btrfs_print_data_csum_error(BTRFS_I(inode), page_offset(page) + pgoff,

				    csum, csum_expected, io_bio->mirror_num);

	if (io_bio->device)

		btrfs_dev_stat_inc_and_print(io_bio->device,

					     BTRFS_DEV_STAT_CORRUPTION_ERRS);
@@ -2955,8 +2967,7 @@ int btrfs_verify_data_csum(struct btrfs_io_bio *io_bio, u64 phy_offset, 
	}



	phy_offset >>= inode->i_sb->s_blocksize_bits;

	return check_data_csum(inode, io_bio, phy_offset, page, offset, start,

			       (size_t)(end - start + 1));

	return check_data_csum(inode, io_bio, phy_offset, page, offset);

}



/*
@@ -7674,8 +7685,7 @@ static blk_status_t btrfs_check_read_dio_bio(struct inode *inode, 
			ASSERT(pgoff < PAGE_SIZE);

			if (uptodate &&

			    (!csum || !check_data_csum(inode, io_bio, icsum,

						       bvec.bv_page, pgoff,

						       start, sectorsize))) {

						       bvec.bv_page, pgoff))) {

				clean_io_failure(fs_info, failure_tree, io_tree,

						 start, bvec.bv_page,

						 btrfs_ino(BTRFS_I(inode)),