[Qemu-devel] [PATCH COLO-BLOCK v7 00/17] Block replication for continuous checkpoints

[Wen Congyang]

Block replication is a very important feature which is used for
continuous checkpoints(for example: COLO).

Usage:
Please refer to docs/block-replication.txt

You can get the patch here:
https://github.com/wencongyang/qemu-colo/commits/block-replication-v7

You can get ths patch with framework here:
https://github.com/wencongyang/qemu-colo/commits/colo_framework_v7.2

TODO:
1. Continuous block replication. It will be started after basic functions
   are accepted.

Changs Log:
V7:
1. Implement adding/removing quorum child. Remove the option non-connect.
2. Simplify the backing refrence option according to Stefan Hajnoczi's 
suggestion
V6:
1. Rebase to the newest qemu.
V5:
1. Address the comments from Gong Lei
2. Speed the failover up. The secondary vm can take over very quickly even
   if there are too many I/O requests.
V4:
1. Introduce a new driver replication to avoid touch nbd and qcow2.
V3:
1: use error_setg() instead of error_set()
2. Add a new block job API
3. Active disk, hidden disk and nbd target uses the same AioContext
4. Add a testcase to test new hbitmap API
V2:
1. Redesign the secondary qemu(use image-fleecing)
2. Use Error objects to return error message
3. Address the comments from Max Reitz and Eric Blake


Wen Congyang (17):
  Add new block driver interface to add/delete a BDS's child
  quorum: implement block driver interfaces add/delete a BDS's child
  hmp: add monitor command to add/remove a child
  introduce a new API qemu_opts_absorb_qdict_by_index()
  quorum: allow ignoring child errors
  introduce a new API to enable/disable attach device model
  introduce a new API to check if blk is attached
  block: make bdrv_put_ref_bh_schedule() as a public API
  Backup: clear all bitmap when doing block checkpoint
  allow writing to the backing file
  Allow creating backup jobs when opening BDS
  block: Allow references for backing files
  docs: block replication's description
  Add new block driver interfaces to control block replication
  skip nbd_target when starting block replication
  quorum: implement block driver interfaces for block replication
  Implement new driver for block replication

 block.c                        | 198 +++++++++++++++++-
 block/Makefile.objs            |   3 +-
 block/backup.c                 |  13 ++
 block/block-backend.c          |  33 +++
 block/quorum.c                 | 244 ++++++++++++++++++++++-
 block/replication.c            | 443 +++++++++++++++++++++++++++++++++++++++++
 blockdev.c                     |  90 ++++++---
 blockjob.c                     |  10 +
 docs/block-replication.txt     | 179 +++++++++++++++++
 hmp-commands.hx                |  28 +++
 include/block/block.h          |  11 +
 include/block/block_int.h      |  19 ++
 include/block/blockjob.h       |  12 ++
 include/qemu/option.h          |   2 +
 include/sysemu/block-backend.h |   3 +
 include/sysemu/blockdev.h      |   2 +
 qapi/block.json                |  16 ++
 util/qemu-option.c             |  44 ++++
 18 files changed, 1303 insertions(+), 47 deletions(-)
 create mode 100644 block/replication.c
 create mode 100644 docs/block-replication.txt

-- 
2.4.3