Discussion for v2:
https://lore.kernel.org/qemu-devel/20240528120114.344416-1-f.eb...@proxmox.com/
Changes in v3:
* Pass min_cluster_size option directly without checking
has_min_cluster_size, because the default is 0 anyways.
* Calculate maximum of passed-in argument and default once at the
beginning of block_copy_calculate_cluster_size()
* Update warning message to reflect actual value used
* Do not leak qdict in error case
* Use PRI{i,u}64 macros
Discussion for v1:
https://lore.kernel.org/qemu-devel/20240308155158.830258-1-f.eb...@proxmox.com/
-
Changes in v2:
* Use 'size' type in QAPI.
* Remove option in cbw_parse_options(), i.e. before parsing generic
blockdev options.
* Reword commit messages hoping to describe the issue in a more
straight-forward way.
In the context of backup fleecing, discarding the source will not work
when the fleecing image has a larger granularity than the one used for
block-copy operations (can happen if the backup target has smaller
cluster size), because cbw_co_pdiscard_snapshot() will align down the
discard requests and thus effectively ignore then.
To make @discard-source work in such a scenario, allow specifying the
minimum cluster size used for block-copy operations and thus in
particular also the granularity for discard requests to the source.
Fiona Ebner (2):
copy-before-write: allow specifying minimum cluster size
backup: add minimum cluster size to performance options
block/backup.c | 2 +-
block/block-copy.c | 36 ++++++++++++++++++++++++++----------
block/copy-before-write.c | 14 +++++++++++++-
block/copy-before-write.h | 1 +
blockdev.c | 3 +++
include/block/block-copy.h | 1 +
qapi/block-core.json | 17 ++++++++++++++---
7 files changed, 59 insertions(+), 15 deletions(-)
--
2.39.2
