Re: [PATCH v3 0/4] Additional parameters for qemu_img map

[Eyal Moscovici]

On 13/05/2020 20:49, Eric Blake wrote:
> On 5/13/20 8:36 AM, Eyal Moscovici wrote:
> > Hi,
> >
> > The following series adds two parameters to qemu-img map:
> > 1. start-offset: mapping starting offset.
> > 2. max-length: the length of the mapping.
> >
> > These parameters proved useful when mapping large disk spread across
> > long store file chains. It allows us to bound the execution time of each
> > qemu-img map execution as well as recover from failed mapping
> > operations. In addition the map operation can divided to
> > multiple independent tasks.
> >
> > V3 changes:
> > 1. Add cvtnum_full and made cvtnum a wrapper function.
> > 2. Keep the original boundaries checks.
> > 3. Tone down error messages.
>
> While this does not directly touch NBD code, I find it quite handy for 
> my tests of incremental backups over NBD (since I frequently use 
> x-dirty-bitmap coupled with qemu-img map to read bitmaps, and 
> subsetting the output is indeed nice), so I'll queue this through my 
> NBD tree.  It may be another week or so before I send a pull request 
> including this and other collected patches.
>
> Congratulations on your first qemu contribution!
Thanks :)
> >  qemu-img.c                 | 76 +++++++++++++++++---------------------
> >  tests/qemu-iotests/049.out |  8 ++--
> >  2 files changed, 38 insertions(+), 46 deletions(-)
>
> This series diffstat is off; later in the series, in 4/4, I see:
I had some copy & paste issues with my cover letter, sorry.
> >  docs/tools/qemu-img.rst |  2 +-
> >  qemu-img-cmds.hx        |  4 ++--
> >  qemu-img.c              | 22 +++++++++++++++++++++-
> >  3 files changed, 24 insertions(+), 4 deletions(-)
>
> What I don't see is any iotest coverage of the new options, to ensure 
> they don't regress.  Either a new iotest, or an enhancement to an 
> existing iotest.  If you feel up to the task, post a 5/4 patch; if 
> not, I'll probably enhance 223 (my x-dirty-bitmap reading code 
> mentioned above).
I will take a look at test 223, and see if I can enhance it.