Re: [Qemu-devel] [PATCH 4/7] block: close unused image files at the end of streaming

[Federico Simoncelli]

----- Original Message -----
> From: "Paolo Bonzini" <address@hidden>
> To: address@hidden
> Cc: "Marcelo Tosatti" <address@hidden>, "Federico Simoncelli" <address@hidden>
> Sent: Thursday, April 5, 2012 5:42:58 PM
> Subject: [PATCH 4/7] block: close unused image files at the end of streaming
> 
> From: Marcelo Tosatti <address@hidden>
> 
> Close the now unused images that were part of the previous backing
> file
> chain and adjust ->backing_hd properly.
> 
> Note that this only works with relative paths.

s/relative/absolute/

> Given the images:
> 
>  /tmp/a/base.raw
>  /tmp/a/snap1.qcow2
>  /tmp/b/snap2.qcow2
> 
> chained as:
> 
>  base(bak:"") <- snap1(bak:"base.raw") <-
>  snap2(bak:"../a/snap1.qcow2")
> 
> merging snap1 and snap2 we will obtain:
> 
>  base(bak:"") <- snap2(bak:"base.raw")
> 
> However this should be maintained by the user/admin: one can also
> screw up relative paths using qemu-img manually.

The patch is fine but I disagree with this comment. The user/admin didn't make
any mistake and he shouldn't be in charge of additional maintenance (which is
also tricky since the VM is running).

-- 
Federico