This patchset is a cleanup of the previous QCOW2 deduplication rfc. One can compile and install https://github.com/wernerd/Skein3Fish and use the --enable-skein-dedup configure option in order to use the faster skein HASH.
Images must be created with "-o dedup=[skein|sha256]" in order to activate the deduplication in the image. Deduplication is now fast enough to be usable. v4: Fix and complete qcow2 spec [Stefan] Hash the hash_algo field in the header extension [Stefan] Fix qcow2 spec [Eric] Remove pointer to hash and simplify hash memory management [Stefan] Rename and move qcow2_read_cluster_data to qcow2.c [Stefan] Document lock dropping behaviour of the previous function [Stefan] cleanup qcow2_dedup_read_missing_cluster_data [Stefan] rename *_offset to *_sect [Stefan] add a ./configure check for ssl [Stefan] Replace openssl by gnutls [Stefan] Implement Skein hashes Rewrite pretty every qcow2-dedup.c commits after Add qcow2_dedup_read_missing_and_concatenate to simplify the code Use 64KB deduplication hash block to reduce allocation flushes Use 64KB l2 tables to reduce allocation flushes [breaks compatibility] Use lazy refcounts to avoid qcow2_cache_set_dependency loops resultings in frequent caches flushes Do not create and load dedup RAM structures when bdrs->read_only is true v3: make it work barely replace kernel red black trees by gtree. *** BLURB HERE *** Benoît Canet (30): qcow2: Add deduplication to the qcow2 specification. qcow2: Add deduplication structures and fields. qcow2: Add qcow2_dedup_read_missing_and_concatenate qcow2: Make update_refcount public. qcow2: Create a way to link to l2 tables when deduplicating. qcow2: Add qcow2_dedup and related functions qcow2: Add qcow2_dedup_store_new_hashes. qcow2: Implement qcow2_compute_cluster_hash. qcow2: Extract qcow2_dedup_grow_table qcow2: Add qcow2_dedup_grow_table and use it. qcow2: create function to load deduplication hashes at startup. qcow2: Load and save deduplication table header extension. qcow2: Extract qcow2_do_table_init. qcow2-cache: Allow to choose table size at creation. qcow2: Add qcow2_dedup_init and qcow2_dedup_close. qcow2: Extract qcow2_add_feature and qcow2_remove_feature. block: Add qemu-img dedup create option. qcow2: Behave correctly when refcount reach 0 or 2^16. qcow2: Integrate deduplication in qcow2_co_writev loop. qcow2: Serialize write requests when deduplication is activated. qcow2: Add verification of dedup table. qcow2: Adapt checking of QCOW_OFLAG_COPIED for dedup. qcow2: Add check_dedup_l2 in order to check l2 of dedup table. qcow2: Do not overwrite existing entries with QCOW_OFLAG_COPIED. qcow2: Integrate SKEIN hash algorithm in deduplication. qcow2: Add lazy refcounts to deduplication to prevent qcow2_cache_set_dependency loops qcow2: Use large L2 table for deduplication. qcow: Set dedup cluster block size to 64KB. qcow2: init and cleanup deduplication. qemu-iotests: Filter dedup=on/off so existing tests don't break. block/Makefile.objs | 1 + block/qcow2-cache.c | 12 +- block/qcow2-cluster.c | 116 +++-- block/qcow2-dedup.c | 1157 ++++++++++++++++++++++++++++++++++++++++++ block/qcow2-refcount.c | 157 ++++-- block/qcow2.c | 357 +++++++++++-- block/qcow2.h | 120 ++++- configure | 55 ++ docs/specs/qcow2.txt | 100 +++- include/block/block_int.h | 1 + tests/qemu-iotests/common.rc | 3 +- 11 files changed, 1955 insertions(+), 124 deletions(-) create mode 100644 block/qcow2-dedup.c -- 1.7.10.4