Re: [Qemu-devel] [PATCH 0/9] block: add differential backup support

[John Snow <jsnow@redhat.com>]

Ping.

(Oh, I forgot to CC Stefan originally. :\)

Stefan: I know you said this wasn't expressly requisite, but I was
encouraged by Kevin to send it out as a usability patch for non-libvirt
users, so here it is.

Final "Yeah sure" or "No, definitely not" as 2.4 approaches?

Also note that if the answer is "Ehhh, maybe not now, nobody's REALLY
asked for it" we should still probably merge the first patch alone,
before our API solidifies -- this will give us the breathing room to add
these features in later if we want.

Thank you,
--John

(Oh, also note that this IS based on the now deprecated transactional
series I wrote, but if there is some use I can likely rebase without
much of a fuss on top of the BlockJobTxn approach.)


On 06/04/2015 08:20 PM, John Snow wrote:
> Requires: 1433454372-16356-1-git-send-email-jsnow@redhat.com
>           [0/10] block: incremental backup transactions
> 
> It's entirely possible to use the incremental backup primitives to
> achieve a differential backup mechanism, but in the interest of
> ease of use, I am proposing the explicit addition of the mechanism
> because it does not particularly complicate the code, add new edge
> cases, or present itself as difficult to test.
> 
> This series actually adds two ease of use features:
> 
> (1) Add a copy primitive for bitmaps to add flexibility to the
>     backup system in case users would like to later run multiple
>     backup chains (weekly vs. monthly or perhaps incremental vs.
>     differential)
> 
> (2) Add a 'differential' backup mode that does what the name says
>     on the tin.
> 
> ==
> For convenience, this branch is available at:
> https://github.com/jnsnow/qemu.git branch differential-backup
> https://github.com/jnsnow/qemu/tree/differential-backup
> 
> This version is tagged differential-backup-v1:
> https://github.com/jnsnow/qemu/releases/tag/differential-backup-v1
> ==
> 
> John Snow (9):
>   qapi: Rename 'dirty-bitmap' mode to 'incremental'
>   hbitmap: add hbitmap_copy
>   block: add bdrv_copy_dirty_bitmap
>   qapi: add Copy data type for bitmaps
>   qmp: add qmp cmd block-dirty-bitmap-copy
>   qmp: add block-dirty-bitmap-copy transaction
>   block: add differential backup mode
>   iotests: 124: support differential backups
>   iotests: add differential backup test
> 
>  block.c                    | 35 +++++++++++++++++-
>  block/backup.c             | 19 ++++++----
>  block/mirror.c             |  9 ++++-
>  blockdev.c                 | 61 +++++++++++++++++++++++++++++++
>  docs/bitmaps.md            |  8 ++--
>  include/block/block.h      |  5 +++
>  include/block/block_int.h  |  2 +-
>  include/qemu/hbitmap.h     |  9 +++++
>  qapi-schema.json           |  4 +-
>  qapi/block-core.json       | 40 ++++++++++++++++++--
>  qmp-commands.hx            | 36 ++++++++++++++++--
>  tests/qemu-iotests/124     | 91 +++++++++++++++++++++++++++++-----------------
>  tests/qemu-iotests/124.out |  4 +-
>  util/hbitmap.c             | 17 +++++++++
>  14 files changed, 280 insertions(+), 60 deletions(-)
> 

-- 
—js