[libvirt] [PATCH 14.5/16] snapshot: Make virDomainMomentObjListGetNames more generic

[John Ferlan]

On 3/22/19 12:25 AM, Eric Blake wrote:
> Rather than hard-coding the snapshot filter bit values into the
> generic code, add another layer of indirection: callers must map which
> of their public filter bits correspond to supported moment bits, then
> pass two separate flags (the ones translated for moment code to
> operate on, and the remaining ones for the filter callback to operate
> on).
> 
> Signed-off-by: Eric Blake <eblake at redhat.com>
> ---
> 
> I realized I don't have to mess with matching public API bits at
> all. But if I'm smart, the bit values I choose for checkpoints will
> match the internal ones supported by moments, so that only the
> snapshot code has to do the mapping.
> 
>  src/conf/virdomainmomentobjlist.h   | 32 ++++++++++++++++++++++++++--
>  src/conf/virdomainmomentobjlist.c   | 33 +++++++++++++++--------------
>  src/conf/virdomainsnapshotobjlist.c | 29 +++++++++++++++++++++++--
>  3 files changed, 74 insertions(+), 20 deletions(-)
> 

[...]

> diff --git a/src/conf/virdomainmomentobjlist.c b/src/conf/virdomainmomentobjlist.c
> index 46bd3e448a..94b927746a 100644
> --- a/src/conf/virdomainmomentobjlist.c
> +++ b/src/conf/virdomainmomentobjlist.c

[...]

> @@ -346,21 +347,21 @@ virDomainMomentObjListGetNames(virDomainMomentObjListPtr moments,
>       * add the ability to track qcow2 internal snapshots without the
>       * use of metadata, in which case this check should move into the
>       * filter callback.  */
> -    if ((data.flags & VIR_DOMAIN_SNAPSHOT_FILTERS_METADATA) ==
> -        VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA)
> +    if ((data.flags & VIR_DOMAIN_MOMENT_FILTERS_METADATA) ==
> +        VIR_DOMAIN_MOMENT_LIST_NO_METADATA)
>          return 0;
> -    data.flags &= ~VIR_DOMAIN_SNAPSHOT_FILTERS_METADATA;
> +    data.flags &= ~VIR_DOMAIN_MOMENT_FILTERS_METADATA;
> 
> -    if (flags & VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS) {
> +    if (flags & VIR_DOMAIN_MOMENT_LIST_DESCENDANTS) {
>          /* We could just always do a topological visit; but it is
>           * possible to optimize for less stack usage and time when a
>           * simpler full hashtable visit or counter will do. */
>          if (from->def || (names &&
> -                          (flags & VIR_DOMAIN_SNAPSHOT_LIST_TOPOLOGICAL)))
> +                          (flags & VIR_DOMAIN_MOMENT_LIST_TOPOLOGICAL)))
>              virDomainMomentForEachDescendant(from,
>                                               virDomainMomentObjListCopyNames,
>                                               &data);
> -        else if (names || data.flags)
> +        else if (names || data.flags || filter_flags)
>              virHashForEach(moments->objs, virDomainMomentObjListCopyNames,
>                             &data);
>          else

Does the data.flags usage just below here calling *ForEachChild using
*ObjListCopyNames need the "|| filter_flags" as well? Seems so with the
call to data->filter possible.

Reviewed-by: John Ferlan <jferlan at redhat.com>

John

[...]