Re: [Qemu-devel] [PATCH v2 00/17] block: transactionless incremental backup series

[Max Reitz <mreitz@redhat.com>]

On 2015-03-02 at 18:19, John Snow wrote:
> New topic, new version, same great incremental backup taste.
>
> This series relies on [Qemu-devel] [PULL 30/69] blkdebug: fix "once" rule,
> part of Stefan's 69 patch pull request submitted 2015-02-27.
>
> This patchset enables the in-memory part of the incremental backup
> feature, without transactional support.
>
> Support for transactions will come at a later date, but getting this
> portion upstream will help stabilize work on bitmap persistence and
> bitmap migration.
>
> Transactional support is being postponed to allow more development
> to create a transactional callback system that will allow objects used
> by the drive backup routines to perform cleanup actions conditionally
> based on the outcome of all backups in the transaction group.
>
> This series was once said to have been written by a man known only
> to Qemu-Devel as "Fam Zheng", A programming maverick hellbent on never
> again wasting space by making full backups when he did not have to. The
> true origins of this series are now lost to the sands of time.
>
> (12+ revisions later: Thanks, Fam!)
>
> ===
> v2:
> ===
>
> 01: Added a new opening blurb.
>      Adjusted codeblock indentations to be 4 spaces instead of 3,

That was easy...

Max

>      so it works as MD or GFMD.
>      Adjusted errors explanation.
>      Make visual separations between json data and shell commands
>      Eliminate any ligering single quotes
>
> 07: Remember that memset takes bytes, not n_items ...
>
> ===
> v1:
> ===
>
> Deletions:
>   - Removed Transactions, to be added later.
>   - Removed Transaction tests, as above.
>
> Changes:
> 01: Indentation fixes.
>      Removed enable/disable documentation.
>      Added a note that transactions aren't implemented yet.
>      Removed my needless commas
>      Added error case documentation.
>
> 07: QMP enable/disable commands are deleted.
>
> 14: Some comments concerning assertions.
>      Scrub re-alloc memory if we expand the array.
>      Do not attempt to scrub memory if fix_count is 0
>
> Changes made with Reviews kept:
>
> 02: Since 2.4
> 04: Since 2.4
>      Demingled the QMP command documentation.
> 08: Additions to what was qmp_block_dirty_enable/disable
>      are no longer present as those function no longer exist.
> 09: Since 2.4
> 10: Since 2.4
>      Demingled QMP command documentation.
> 11: Since 2.4
> 15: Test 112 --> 124
> 17: Number of tests altered. (Only 4, now.)
>
> Fam Zheng (1):
>    qapi: Add optional field "name" to block dirty bitmap
>
> John Snow (16):
>    docs: incremental backup documentation
>    qmp: Ensure consistent granularity type
>    qmp: Add block-dirty-bitmap-add and block-dirty-bitmap-remove
>    block: Introduce bdrv_dirty_bitmap_granularity()
>    hbitmap: add hbitmap_merge
>    block: Add bitmap disabled status
>    block: Add bitmap successors
>    qmp: Add support of "dirty-bitmap" sync mode for drive-backup
>    qmp: add block-dirty-bitmap-clear
>    qmp: Add dirty bitmap status fields in query-block
>    block: add BdrvDirtyBitmap documentation
>    block: Ensure consistent bitmap function prototypes
>    block: Resize bitmaps on bdrv_truncate
>    iotests: add invalid input incremental backup tests
>    iotests: add simple incremental backup case
>    iotests: add incremental backup failure recovery test
>
>   block.c                       | 248 +++++++++++++++++++++++++++++++--
>   block/backup.c                | 149 ++++++++++++++++----
>   block/mirror.c                |  46 +++----
>   blockdev.c                    | 162 +++++++++++++++++++++-
>   docs/bitmaps.md               | 311 ++++++++++++++++++++++++++++++++++++++++++
>   hmp.c                         |   3 +-
>   include/block/block.h         |  34 ++++-
>   include/block/block_int.h     |   4 +-
>   include/qemu/hbitmap.h        |  21 +++
>   migration/block.c             |   9 +-
>   qapi/block-core.json          |  92 ++++++++++++-
>   qmp-commands.hx               |  92 ++++++++++++-
>   tests/qemu-iotests/124        | 266 ++++++++++++++++++++++++++++++++++++
>   tests/qemu-iotests/124.out    |   5 +
>   tests/qemu-iotests/group      |   1 +
>   tests/qemu-iotests/iotests.py |   6 +-
>   util/hbitmap.c                |  87 ++++++++++++
>   17 files changed, 1446 insertions(+), 90 deletions(-)
>   create mode 100644 docs/bitmaps.md
>   create mode 100644 tests/qemu-iotests/124
>   create mode 100644 tests/qemu-iotests/124.out
>