[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PULL 06/18] qemu-img: Add --target-is-zero to convert

From: David Edmondson
Subject: Re: [PULL 06/18] qemu-img: Add --target-is-zero to convert
Date: Thu, 20 Feb 2020 20:18:44 +0000

On Thursday, 2020-02-20 at 10:36:04 -06, Eric Blake wrote:

> On 2/20/20 10:06 AM, Max Reitz wrote:
>> From: David Edmondson <address@hidden>
>> In many cases the target of a convert operation is a newly provisioned
>> target that the user knows is blank (reads as zero). In this situation
>> there is no requirement for qemu-img to wastefully zero out the entire
>> device.
>> Add a new option, --target-is-zero, allowing the user to indicate that
>> an existing target device will return zeros for all reads.
>> Signed-off-by: David Edmondson <address@hidden>
>> Message-Id: <address@hidden>
>> Reviewed-by: Vladimir Sementsov-Ogievskiy <address@hidden>
>> Reviewed-by: Eric Blake <address@hidden>
>> Signed-off-by: Max Reitz <address@hidden>
>> ---
>>   docs/interop/qemu-img.rst |  9 ++++++++-
>>   qemu-img-cmds.hx          |  4 ++--
>>   qemu-img.c                | 26 +++++++++++++++++++++++---
>>   3 files changed, 33 insertions(+), 6 deletions(-)
>> diff --git a/docs/interop/qemu-img.rst b/docs/interop/qemu-img.rst
>> index 42e4451db4..5f40137c10 100644
>> --- a/docs/interop/qemu-img.rst
>> +++ b/docs/interop/qemu-img.rst
>> @@ -214,6 +214,13 @@ Parameters to convert subcommand:
>>     will still be printed.  Areas that cannot be read from the source will be
>>     treated as containing only zeroes.
>> +.. option:: --target-is-zero
>> +
>> +  Assume that reading the destination image will always return
>> +  zeros. This parameter is mutually exclusive with a destination image
> Late tweak now that this is in a pull request, so we may want a followup 
> patch, but:
> The image doesn't always return zeros after we write to it, maybe we 
> should tweak this sentence:
> Assume that reading the destination image will initially return all zeros.

I will send a patch for this.

> Also, my earlier comment about 'zeroes' one line before 'zeros' still 
> applies - although both spellings are valid, we look inconsistent when 
> we can't make up our mind within two adjacent paragraphs.

If we can agree on one of "zeros" or "zeroes" then I'm happy to send a
patch making it consistent everywhere.

I think that given there are existing functions with "zeroes" in the
name, I'd be inclined to go that way.

Why stay in college? Why go to night school?

reply via email to

[Prev in Thread] Current Thread [Next in Thread]