22.07.2020 15:22, Max Reitz wrote:
On 01.06.20 20:11, Vladimir Sementsov-Ogievskiy wrote:
Add new parameters to configure future backup features. The patch
doesn't introduce aio backup requests (so we actually have only one
worker) neither requests larger than one cluster. Still, formally we
satisfy these maximums anyway, so add the parameters now, to facilitate
further patch which will really change backup job behavior.
Options are added with x- prefixes, as the only use for them are some
very conservative iotests which will be updated soon.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
---
qapi/block-core.json | 9 ++++++++-
include/block/block_int.h | 7 +++++++
block/backup.c | 21 +++++++++++++++++++++
block/replication.c | 2 +-
blockdev.c | 5 +++++
5 files changed, 42 insertions(+), 2 deletions(-)
[..]
@@ -422,6 +436,11 @@ BlockJob *backup_job_create(const char *job_id,
BlockDriverState *bs,
if (cluster_size < 0) {
goto error;
}
+ if (max_chunk && max_chunk < cluster_size) {
+ error_setg(errp, "Required max-chunk (%" PRIi64") is less than backup "
(missing a space after PRIi64)
+ "cluster size (%" PRIi64 ")", max_chunk, cluster_size);
Should this be noted in the QAPI documentation?
Hmm.. It makes sense, but I don't know what to write: should be >= job
cluster_size? But then I'll have to describe the logic of
backup_calculate_cluster_size()...
(And perhaps the fact
that without copy offloading, we’ll never copy anything bigger than one
cluster at a time anyway?)
This is a parameter for background copying. Look at block_copy_task_create(),
if call_state has own max_chunk, it's used instead of common copy_size (derived
from cluster_size). But at a moment of this patch background process through
async block-copy is not yet implemented, and the parameter doesn't work, which
is described in commit message.
+ return NULL;
+ }
/*
[..]
--
Best regards,
Vladimir
