[Qemu-devel] [Patch v12 00/10] Block replication for continuous checkpoints

[Wen Congyang <wency@cn.fujitsu.com>]

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

You can get the detailed information about block replication from here:
http://wiki.qemu.org/Features/BlockReplication

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

This patch series is based on the following patch series:
1. http://lists.nongnu.org/archive/html/qemu-devel/2015-11/msg04949.html
2. http://lists.nongnu.org/archive/html/qemu-devel/2015-11/msg06043.html

You can get the patch here:
https://github.com/coloft/qemu/tree/wency/block-replication-v12

You can get the patch with framework here:
https://github.com/coloft/qemu/tree/wency/colo_framework_v11.2

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

Changs Log:
V12:
1. Rebase to the newest codes
2. Use backing reference to replcace 'allow-write-backing-file'
V11:
1. Reopen the backing file when starting blcok replication if it is not
   opened in R/W mode
2. Unblock BLOCK_OP_TYPE_BACKUP_SOURCE and BLOCK_OP_TYPE_BACKUP_TARGET
   when opening backing file
3. Block the top BDS so there is only one block job for the top BDS and
   its backing chain.
V10:
1. Use blockdev-remove-medium and blockdev-insert-medium to replace backing
   reference.
2. Address the comments from Eric Blake
V9:
1. Update the error messages
2. Rebase to the newest qemu
3. Split child add/delete support. These patches are sent in another patchset.
V8:
1. Address Alberto Garcia's comments
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 (10):
  unblock backup operations in backing file
  Store parent BDS in BdrvChild
  Backup: clear all bitmap when doing block checkpoint
  Allow creating backup jobs when opening BDS
  docs: block replication's description
  Add new block driver interfaces to control block replication
  quorum: implement block driver interfaces for block replication
  Implement new driver for block replication
  support replication driver in blockdev-add
  Add a new API to start/stop replication, do checkpoint to all BDSes

 block.c                    | 145 ++++++++++++
 block/Makefile.objs        |   3 +-
 block/backup.c             |  14 ++
 block/quorum.c             |  78 +++++++
 block/replication.c        | 549 +++++++++++++++++++++++++++++++++++++++++++++
 blockjob.c                 |  11 +
 docs/block-replication.txt | 227 +++++++++++++++++++
 include/block/block.h      |   9 +
 include/block/block_int.h  |  15 ++
 include/block/blockjob.h   |  12 +
 qapi/block-core.json       |  34 ++-
 11 files changed, 1093 insertions(+), 4 deletions(-)
 create mode 100644 block/replication.c
 create mode 100644 docs/block-replication.txt

-- 
2.5.0