On Mon, Feb 12, 2024 at 05:58:05PM +0100, Andrey Albershteyn wrote:
> + u64 block_offset;
'hblock_pos', to make it clear that it's in bytes, and that it's for the hash
block, not the data block.
> + u64 ra_bytes = 0;
> + u64 tree_size;
>
> /*
> * The index of the block in the current level; also the index
> @@ -105,18 +106,20 @@ verify_data_block(struct inode *inode, struct fsverity_info *vi,
> /* Index of the hash block in the tree overall */
> hblock_idx = params->level_start[level] + next_hidx;
>
> - /* Index of the hash page in the tree overall */
> - hpage_idx = hblock_idx >> params->log_blocks_per_page;
> + /* Offset of the Merkle tree block into the tree */
> + block_offset = hblock_idx << params->log_blocksize;
>
> /* Byte offset of the hash within the block */
> hoffset = (hidx << params->log_digestsize) &
> (params->block_size - 1);
>
> - num_ra_pages = level == 0 ?
> - min(max_ra_pages, params->tree_pages - hpage_idx) : 0;
> + if (level == 0) {
> + tree_size = params->tree_pages << PAGE_SHIFT;
> + ra_bytes = min(max_ra_bytes, (tree_size - block_offset));
> + }
How about:
ra_bytes = level == 0 ?
min(max_ra_bytes, params->tree_size - hblock_pos) : 0;
- Eric
