V1 was here: https://lists.gnu.org/archive/html/qemu-devel/2025-04/msg01654.html
In v2: - Rearrange and split several patches - Fewer changes to file-posix.c; instead, - New bdrv_co_is_all_zeroes() in io.c, which works on both file-posix and NBD - Clean up several corner cases spotted during review - Better iotest coverage, required pulling in Andrey's patch for disk_usage Andrey Drobyshev (1): iotests/common.rc: add disk_usage function Eric Blake (10): block: Expand block status mode from bool to enum file-posix: Handle zero block status hint better block: Let bdrv_co_is_zero_fast consolidate adjacent extents block: Add new bdrv_co_is_all_zeroes() function iotests: Improve iotest 194 to mirror data mirror: Minor refactoring mirror: Skip pre-zeroing destination if it is already zero mirror: Skip writing zeroes when target is already zero tests: Add iotest mirror-sparse for recent patches mirror: Allow QMP override to declare target already zero qapi/block-core.json | 8 +- block/coroutines.h | 4 +- include/block/block-common.h | 26 ++++ include/block/block-io.h | 2 + include/block/block_int-common.h | 25 ++-- include/block/block_int-global-state.h | 3 +- include/block/block_int-io.h | 4 +- block/io.c | 120 ++++++++++++---- block/blkdebug.c | 6 +- block/copy-before-write.c | 4 +- block/file-posix.c | 5 +- block/gluster.c | 4 +- block/iscsi.c | 6 +- block/mirror.c | 121 +++++++++++++--- block/nbd.c | 4 +- block/null.c | 6 +- block/parallels.c | 6 +- block/qcow.c | 2 +- block/qcow2.c | 6 +- block/qed.c | 6 +- block/quorum.c | 4 +- block/raw-format.c | 4 +- block/rbd.c | 6 +- block/snapshot-access.c | 4 +- block/vdi.c | 4 +- block/vmdk.c | 2 +- block/vpc.c | 2 +- block/vvfat.c | 6 +- blockdev.c | 18 ++- tests/unit/test-block-iothread.c | 4 +- tests/qemu-iotests/common.rc | 6 + tests/qemu-iotests/194 | 1 + tests/qemu-iotests/250 | 5 - tests/qemu-iotests/tests/mirror-sparse | 109 +++++++++++++++ tests/qemu-iotests/tests/mirror-sparse.out | 153 +++++++++++++++++++++ 35 files changed, 571 insertions(+), 125 deletions(-) create mode 100755 tests/qemu-iotests/tests/mirror-sparse create mode 100644 tests/qemu-iotests/tests/mirror-sparse.out -- 2.49.0
