Hi all!
It's an alternative lock-less solution to
[PATCH v4 0/3] qcow2: fix parallel rewrite and discard (rw-lock)
In v6 a lot of things are rewritten.
What is changed:
1. rename the feature to host_range_refcnt, move it to separate file
2. better naming for everything (I hope)
3. cover reads, not only writes
4. do "ref" in qcow2_get_host_offset(), qcow2_alloc_host_offset(),
qcow2_alloc_compressed_cluster_offset().
and callers do "unref" appropriately.
Vladimir Sementsov-Ogievskiy (12):
iotests: add qcow2-discard-during-rewrite
qcow2: fix cache discarding in update_refcount()
block/qcow2-cluster: assert no data_file on compressed write path
block/qcow2-refcount: rename and publish update_refcount_discard()
block/qcow2: introduce qcow2_parse_compressed_cluster_descriptor()
block/qcow2: refactor qcow2_co_preadv_task() to have one return
block/qcow2: qcow2_co_pwrite_zeroes: use QEMU_LOCK_GUARD
qcow2: introduce is_cluster_free() helper
qcow2: introduce host-range-refs
qcow2: introduce qcow2_host_cluster_postponed_discard()
qcow2: protect data writing by host range reference
qcow2: protect data reading by host range reference
block/qcow2.h | 26 +++
block/qcow2-cluster.c | 55 +++++-
block/qcow2-host-range-refs.c | 174 ++++++++++++++++++
block/qcow2-refcount.c | 61 ++++--
block/qcow2.c | 118 ++++++++----
block/meson.build | 1 +
.../tests/qcow2-discard-during-rewrite | 72 ++++++++
.../tests/qcow2-discard-during-rewrite.out | 21 +++
8 files changed, 475 insertions(+), 53 deletions(-)
create mode 100644 block/qcow2-host-range-refs.c
create mode 100755 tests/qemu-iotests/tests/qcow2-discard-during-rewrite
create mode 100644 tests/qemu-iotests/tests/qcow2-discard-during-rewrite.out
--
2.29.2
