I've collected several improvements for qcow2 zero-cluster handling. Available as a tag at: git fetch git://repo.or.cz/qemu/ericb.git nbd-blkdebug-v13
Marked as v13 for "hysterical raisins", since it it the half of v10 [1] that was not resubmitted as v11 [2]. Depends on Max's block tree: https://lists.gnu.org/archive/html/qemu-devel/2017-05/msg00641.html and on Max's qcow2 cleanups: https://lists.gnu.org/archive/html/qemu-devel/2017-05/msg00689.html [1] https://lists.gnu.org/archive/html/qemu-devel/2017-04/msg05227.html [2] https://lists.gnu.org/archive/html/qemu-devel/2017-04/msg05896.html [3] https://lists.gnu.org/archive/html/qemu-devel/2017-05/msg00722.html Changes since last posting (v12 [3]): - 2 more new patches: split indentation from other changes (patch 1), and add a typedef (patch 5) - address Max's findings 001/12:[down] 'qcow2: Nicer variable names in qcow2_update_snapshot_refcount()' 002/12:[0040] [FC] 'qcow2: Use consistent switch indentation' 003/12:[----] [--] 'block: Update comments on BDRV_BLOCK_* meanings' 004/12:[----] [--] 'qcow2: Correctly report status of preallocated zero clusters' 005/12:[down] 'qcow2: Name typedef for cluster type' 006/12:[0032] [FC] 'qcow2: Make distinction between zero cluster types obvious' 007/12:[0002] [FC] 'qcow2: Optimize zero_single_l2() to minimize L2 churn' 008/12:[0002] [FC] 'iotests: Improve _filter_qemu_img_map' 009/12:[0010] [FC] 'iotests: Add test 179 to cover write zeroes with unmap' 010/12:[0003] [FC] 'qcow2: Optimize write zero of unaligned tail cluster' 011/12:[----] [--] 'qcow2: Assert that cluster operations are aligned' 012/12:[----] [--] 'qcow2: Discard/zero clusters by byte count' Eric Blake (12): qcow2: Nicer variable names in qcow2_update_snapshot_refcount() qcow2: Use consistent switch indentation block: Update comments on BDRV_BLOCK_* meanings qcow2: Correctly report status of preallocated zero clusters qcow2: Name typedef for cluster type qcow2: Make distinction between zero cluster types obvious qcow2: Optimize zero_single_l2() to minimize L2 churn iotests: Improve _filter_qemu_img_map iotests: Add test 179 to cover write zeroes with unmap qcow2: Optimize write zero of unaligned tail cluster qcow2: Assert that cluster operations are aligned qcow2: Discard/zero clusters by byte count block/qcow2.h | 23 +++-- include/block/block.h | 35 ++++---- include/block/block_int.h | 7 ++ block/qcow2-cluster.c | 181 ++++++++++++++++++++++----------------- block/qcow2-refcount.c | 144 +++++++++++++++---------------- block/qcow2-snapshot.c | 7 +- block/qcow2.c | 38 ++++---- tests/qemu-iotests/common.filter | 4 +- tests/qemu-iotests/060.out | 6 +- tests/qemu-iotests/122.out | 16 ++-- tests/qemu-iotests/154 | 160 +++++++++++++++++++++++++++++++++- tests/qemu-iotests/154.out | 158 ++++++++++++++++++++++++++++++---- tests/qemu-iotests/179 | 130 ++++++++++++++++++++++++++++ tests/qemu-iotests/179.out | 156 +++++++++++++++++++++++++++++++++ tests/qemu-iotests/group | 1 + 15 files changed, 840 insertions(+), 226 deletions(-) create mode 100755 tests/qemu-iotests/179 create mode 100644 tests/qemu-iotests/179.out -- 2.9.3
