qemu-img should use QMP commands whenever possible in order to ensure feature completeness of both online and offline image operations. For the "commit" command, this is relatively easy, so implement it first (in the hope that indeed others will follow).
As qemu-img does not have access to QMP (due to QMP being intertwined with basically everything in qemu), we cannot directly use QMP, but at least use the functions the corresponding QMP commands are using (which would be "block-commit", in this case). v14: - Patch 3: - Pull the optimized code out into an own function [Kevin] - Only run the optimized code if the image header, the reftable, a single refblock and the L1 table can be described by that single refblock [Kevin] - Zero out the L1 table before modifying anything else [Kevin] - Always set bs->drv to NULL if an error occured which broke the in-memory refcount information and thus rendered the BDS unusable (because all of the qcow2 code assumes that the in-memory information is correct, obviously) [Kevin] - Do truncation last, because while it is the eventual goal, it is also the structurally least invasive and therefore least important operation (we don't want it to fail and leave the BDS unusable) [Kevin] - Patch 6: In the meantime, two more places which test data/len have crept in, remove them [Kevin] - Patch 8: - Drop the block_job_resume() call [Kevin, although he'd probably prefer not to be mentioned for this] - Improve error message when there is no backing file [Kevin] - Patch 10: Rebase onto patch 8 (dropped block_job_resume()) - Patch 11: - Rebase onto patch 8 (different error message if the base image has not been explicitly specified) - Explanation about what "For reasons of consistency" means (or at least an example of inconsistency) [Kevin] - Patch 14: - Write some data to the top image so it can be leaked - Swap order of l1_update and empty_image_prepare (l1_update now occurs before empty_image_prepare; the second l1_update occurs at the same time as the reftable_update, so it's safe to omit that one) - Output changed accordingly git-backport-diff against v13: Key: [----] : patches are identical [####] : number of functional differences between upstream/downstream patch [down] : patch is downstream-only The flags [FC] indicate (F)unctional and (C)ontextual differences, respectively 001/14:[----] [--] 'qcow2: Allow "full" discard' 002/14:[----] [--] 'qcow2: Implement bdrv_make_empty()' 003/14:[0306] [FC] 'qcow2: Optimize bdrv_make_empty()' 004/14:[----] [--] 'blockjob: Introduce block_job_complete_sync()' 005/14:[----] [--] 'blockjob: Add "ready" field' 006/14:[0002] [FC] 'iotests: Omit length/offset test in 040 and 041' 007/14:[----] [--] 'block/mirror: Improve progress report' 008/14:[0009] [FC] 'qemu-img: Implement commit like QMP' 009/14:[----] [--] 'qemu-img: Empty image after commit' 010/14:[0001] [FC] 'qemu-img: Enable progress output for commit' 011/14:[0019] [FC] 'qemu-img: Specify backing file for commit' 012/14:[----] [--] 'iotests: Add _filter_qemu_img_map' 013/14:[----] [--] 'iotests: Add test for backing-chain commits' 014/14:[0026] [FC] 'iotests: Add test for qcow2's bdrv_make_empty' Max Reitz (14): qcow2: Allow "full" discard qcow2: Implement bdrv_make_empty() qcow2: Optimize bdrv_make_empty() blockjob: Introduce block_job_complete_sync() blockjob: Add "ready" field iotests: Omit length/offset test in 040 and 041 block/mirror: Improve progress report qemu-img: Implement commit like QMP qemu-img: Empty image after commit qemu-img: Enable progress output for commit qemu-img: Specify backing file for commit iotests: Add _filter_qemu_img_map iotests: Add test for backing-chain commits iotests: Add test for qcow2's bdrv_make_empty block/Makefile.objs | 3 +- block/blkdebug.c | 2 + block/mirror.c | 34 ++++--- block/qcow2-cluster.c | 27 ++++-- block/qcow2-snapshot.c | 2 +- block/qcow2.c | 192 ++++++++++++++++++++++++++++++++++++++- block/qcow2.h | 2 +- blockjob.c | 42 +++++++-- include/block/block.h | 2 + include/block/blockjob.h | 20 ++++ qapi/block-core.json | 4 +- qemu-img-cmds.hx | 4 +- qemu-img.c | 147 +++++++++++++++++++++++++----- qemu-img.texi | 16 +++- tests/qemu-iotests/040 | 4 +- tests/qemu-iotests/041 | 5 +- tests/qemu-iotests/097 | 122 +++++++++++++++++++++++++ tests/qemu-iotests/097.out | 119 ++++++++++++++++++++++++ tests/qemu-iotests/098 | 82 +++++++++++++++++ tests/qemu-iotests/098.out | 52 +++++++++++ tests/qemu-iotests/common.filter | 7 ++ tests/qemu-iotests/group | 2 + tests/qemu-iotests/iotests.py | 3 +- 23 files changed, 823 insertions(+), 70 deletions(-) create mode 100755 tests/qemu-iotests/097 create mode 100644 tests/qemu-iotests/097.out create mode 100755 tests/qemu-iotests/098 create mode 100644 tests/qemu-iotests/098.out -- 1.9.3