From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH for-4.6 5/8] tools/libxl: Save and restore
 EMULATOR_XENSTORE_DATA content
Date: Fri, 31 Jul 2015 17:38:23 +0100
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To: Ian Jackson <Ian.Jackson@eu.citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>, Ian Campbell <Ian.Campbell@citrix.com>, Xen-devel <xen-devel@lists.xen.org>
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On 31/07/15 17:34, Ian Jackson wrote:
> Andrew Cooper writes ("Re: [PATCH for-4.6 5/8] tools/libxl: Save and restore EMULATOR_XENSTORE_DATA content"):
>> On 29/07/15 12:49, Ian Jackson wrote:
>>>> +    rel_start = strlen(xs_path) - 7;
>>> This is horrible.
>> What do you recommend instead?
> I don't see why it is necessary to do something like rel_start at all.
>
> This whole patch could probably be made much simpler with something
> like
>
>    static const char *const physmap_entries[] = {
>        "start_addr", "size", "name", NULL
>    };
>
> and then loop over it a few times.

But the rel_path has nothing to do with which subkeys get chosen.

It is to strip out the current domains information from
/local/domain/$dm_domid/device-model/$domid/.

This is because both of the domid in the path will be different on the
other side of migration.  This is why EMULATOR_XENSTORE_DATA is
purposefully specified relative to the above path, rather than as
absolute paths.

~Andrew