Commit 3d49d0d3 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by David Sterba
Browse files

btrfs: remove now unused checksumming helpers 



Remove the unused btrfs_verify_data_csum helper, and fold
btrfs_check_data_csum into its only caller.

Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent ac9f942e

fs/btrfs/btrfs_inode.h

+0 −5
Original line number Diff line number Diff line
@@ -421,13 +421,8 @@ blk_status_t btrfs_submit_bio_start_direct_io(struct btrfs_inode *inode, 
					      u64 dio_file_offset);

int btrfs_check_sector_csum(struct btrfs_fs_info *fs_info, struct page *page,

			    u32 pgoff, u8 *csum, const u8 * const csum_expected);

int btrfs_check_data_csum(struct btrfs_inode *inode, struct btrfs_bio *bbio,

			  u32 bio_offset, struct page *page, u32 pgoff);

bool btrfs_data_csum_ok(struct btrfs_bio *bbio, struct btrfs_device *dev,

			u32 bio_offset, struct bio_vec *bv);

unsigned int btrfs_verify_data_csum(struct btrfs_bio *bbio,

				    u32 bio_offset, struct page *page,

				    u64 start, u64 end);

noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,

			      u64 *orig_start, u64 *orig_block_len,

			      u64 *ram_bytes, bool nowait, bool strict);

fs/btrfs/inode.c

+16 −108
Original line number Diff line number Diff line
@@ -3456,45 +3456,6 @@ static u8 *btrfs_csum_ptr(const struct btrfs_fs_info *fs_info, u8 *csums, u64 of 
	return csums + offset_in_sectors * fs_info->csum_size;

}



/*

 * check_data_csum - verify checksum of one sector of uncompressed data

 * @inode:	inode

 * @bbio:	btrfs_bio which contains the csum

 * @bio_offset:	offset to the beginning of the bio (in bytes)

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

 * @pgoff:	offset inside the page

 *

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

 *

 * When csum mismatch is detected, we will also report the error and fill the

 * corrupted range with zero. (Thus it needs the extra parameters)

 */

int btrfs_check_data_csum(struct btrfs_inode *inode, struct btrfs_bio *bbio,

			  u32 bio_offset, struct page *page, u32 pgoff)

{

	struct btrfs_fs_info *fs_info = inode->root->fs_info;

	u32 len = fs_info->sectorsize;

	u8 *csum_expected;

	u8 csum[BTRFS_CSUM_SIZE];



	ASSERT(pgoff + len <= PAGE_SIZE);



	csum_expected = btrfs_csum_ptr(fs_info, bbio->csum, bio_offset);



	if (btrfs_check_sector_csum(fs_info, page, pgoff, csum, csum_expected))

		goto zeroit;

	return 0;



zeroit:

	btrfs_print_data_csum_error(inode, bbio->file_offset + bio_offset,

				    csum, csum_expected, bbio->mirror_num);

	if (bbio->device)

		btrfs_dev_stat_inc_and_print(bbio->device,

					     BTRFS_DEV_STAT_CORRUPTION_ERRS);

	memzero_page(page, pgoff, len);

	return -EIO;

}



/*

 * Verify the checksum of a single data sector.

 *
@@ -3512,8 +3473,13 @@ bool btrfs_data_csum_ok(struct btrfs_bio *bbio, struct btrfs_device *dev, 
			u32 bio_offset, struct bio_vec *bv)

{

	struct btrfs_inode *inode = bbio->inode;

	struct btrfs_fs_info *fs_info = inode->root->fs_info;

	u64 file_offset = bbio->file_offset + bio_offset;

	u64 end = file_offset + bv->bv_len - 1;

	u8 *csum_expected;

	u8 csum[BTRFS_CSUM_SIZE];



	ASSERT(bv->bv_len == fs_info->sectorsize);



	if (!bbio->csum)

		return true;
@@ -3527,77 +3493,19 @@ bool btrfs_data_csum_ok(struct btrfs_bio *bbio, struct btrfs_device *dev, 
		return true;

	}



	if (btrfs_check_data_csum(inode, bbio, bio_offset, bv->bv_page,

				  bv->bv_offset) < 0)

		return false;

	csum_expected = btrfs_csum_ptr(fs_info, bbio->csum, bio_offset);

	if (btrfs_check_sector_csum(fs_info, bv->bv_page, bv->bv_offset, csum,

				    csum_expected))

		goto zeroit;

	return true;

}



/*

 * When reads are done, we need to check csums to verify the data is correct.

 * if there's a match, we allow the bio to finish.  If not, the code in

 * extent_io.c will try to find good copies for us.

 *

 * @bio_offset:	offset to the beginning of the bio (in bytes)

 * @start:	file offset of the range start

 * @end:	file offset of the range end (inclusive)

 *

 * Return a bitmap where bit set means a csum mismatch, and bit not set means

 * csum match.

 */

unsigned int btrfs_verify_data_csum(struct btrfs_bio *bbio,

				    u32 bio_offset, struct page *page,

				    u64 start, u64 end)

{

	struct btrfs_inode *inode = BTRFS_I(page->mapping->host);

	struct btrfs_root *root = inode->root;

	struct btrfs_fs_info *fs_info = root->fs_info;

	struct extent_io_tree *io_tree = &inode->io_tree;

	const u32 sectorsize = root->fs_info->sectorsize;

	u32 pg_off;

	unsigned int result = 0;



	/*

	 * This only happens for NODATASUM or compressed read.

	 * Normally this should be covered by above check for compressed read

	 * or the next check for NODATASUM.  Just do a quicker exit here.

	 */

	if (bbio->csum == NULL)

		return 0;



	if (inode->flags & BTRFS_INODE_NODATASUM)

		return 0;



	if (unlikely(test_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state)))

		return 0;



	ASSERT(page_offset(page) <= start &&

	       end <= page_offset(page) + PAGE_SIZE - 1);

	for (pg_off = offset_in_page(start);

	     pg_off < offset_in_page(end);

	     pg_off += sectorsize, bio_offset += sectorsize) {

		u64 file_offset = pg_off + page_offset(page);

		int ret;



		if (btrfs_is_data_reloc_root(root) &&

		    test_range_bit(io_tree, file_offset,

				   file_offset + sectorsize - 1,

				   EXTENT_NODATASUM, 1, NULL)) {

			/* Skip the range without csum for data reloc inode */

			clear_extent_bits(io_tree, file_offset,

					  file_offset + sectorsize - 1,

					  EXTENT_NODATASUM);

			continue;

		}

		ret = btrfs_check_data_csum(inode, bbio, bio_offset, page, pg_off);

		if (ret < 0) {

			const int nr_bit = (pg_off - offset_in_page(start)) >>

				     root->fs_info->sectorsize_bits;



			result |= (1U << nr_bit);

		}

	}

	return result;

zeroit:

	btrfs_print_data_csum_error(inode, file_offset, csum, csum_expected,

				    bbio->mirror_num);

	if (dev)

		btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS);

	memzero_bvec(bv);

	return false;

}



/*