On Mon, Jan 06, 2020 at 12:55:33PM -0800, Eric Biggers wrote: > From: Eric Biggers <ebiggers@xxxxxxxxxx> > > When fs-verity verifies data pages, currently it reads each Merkle tree > page synchronously using read_mapping_page(). > > Therefore, when the Merkle tree pages aren't already cached, fs-verity > causes an extra 4 KiB I/O request for every 512 KiB of data (assuming > that the Merkle tree uses SHA-256 and 4 KiB blocks). This results in > more I/O requests and performance loss than is strictly necessary. > > Therefore, implement readahead of the Merkle tree pages. Looks good. Feel free to add: Reviewed-by: Theodore Ts'o <tytso@xxxxxxx> (for the ext4 and fs/verity bits)
