With active mode, the guest write speed is limited by the synchronous writes to the mirror target. For this reason, management applications might want to start out in background mode and only switch to active mode later, when certain conditions are met. This series adds a block-job-change QMP command to acheive that, as well as job-type-specific information when querying block jobs, which can be used to decide when the switch should happen.
For now, only the direction background -> active is supported. The information added upon querying is whether the target is actively synced, the total data sent, and the remaining dirty bytes. Initially, I tried to go for a more general 'job-change' command, but I couldn't figure out a way to avoid mutual inclusion between block-core.json and job.json. Fiona Ebner (9): blockjob: introduce block-job-change QMP command block/mirror: set actively_synced even after the job is ready mirror: implement mirror_change method qapi/block-core: use JobType for BlockJobInfo's type qapi/block-core: turn BlockJobInfo into a union blockjob: query driver-specific info via a new 'query' driver method mirror: return mirror-specific information upon query mirror: return the remaining dirty bytes upon query mirror: return the total number of bytes sent upon query block/mirror.c | 61 ++++++++++++++++++++++++++++++-- block/monitor/block-hmp-cmds.c | 4 +-- blockdev.c | 14 ++++++++ blockjob.c | 26 +++++++++++++- include/block/blockjob.h | 11 ++++++ include/block/blockjob_int.h | 10 ++++++ job.c | 1 + qapi/block-core.json | 63 ++++++++++++++++++++++++++++++++-- qapi/job.json | 4 ++- 9 files changed, 184 insertions(+), 10 deletions(-) -- 2.30.2