[libvirt PATCH v2 07/16] qemu: use file cache for nbdkit caps

[Peter Krempa]

On Wed, Aug 31, 2022 at 13:40:52 -0500, Jonathon Jongsma wrote:
> Switch to using the virFileCache implementation for nbdkit capabilities
> so that we have persistent caching and re-load capabilities whenever
> something changes.

IMO it would be better to simply start with the proper implementation
from the beginning.

Thus don't add the cache to struct _virQEMUDriver until this patch.

Similarly qemuQueryNbdkitCaps can be dropped from the patch that added
it originally.