tree ae2abf74cff5203e1e4d985da7719c59ffe51ac4
parent 59a0fcdb489dae25416e93b9fc67cc97a6847f01
author David Sterba <dsterba@suse.com> 1582833647 +0100
committer David Sterba <dsterba@suse.com> 1584979312 +0100

btrfs: simplify tree block checksumming loop

Thw whole point of csum_tree_block is to iterate over all extent buffer
pages and pass it to checksumming functions. The bytes where checksum is
stored must be skipped, thus map_private_extent_buffer. This complicates
further offset calculations.

As the first page will be always present, checksum the relevant bytes
unconditionally and then do a simple iteration over the remaining pages.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>