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Date:   Wed, 13 Apr 2022 07:55:24 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Jason Gunthorpe <jgg@nvidia.com>
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Subject: Re: [PATCH 1/9] vfio: Make vfio_(un)register_notifier accept a
 vfio_device
Message-ID: <20220413055524.GB32092@lst.de>
References: <0-v1-a8faf768d202+125dd-vfio_mdev_no_group_jgg@nvidia.com> <1-v1-a8faf768d202+125dd-vfio_mdev_no_group_jgg@nvidia.com>
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On Tue, Apr 12, 2022 at 12:53:28PM -0300, Jason Gunthorpe wrote:
> All callers have a struct vfio_device trivially available, pass it in
> directly and avoid calling the expensive vfio_group_get_from_dev().

Instead of bothering the drivers with the notifiers at all, the two
notifier_blocks should move into struct vfio_device, and the
vfio_ops should just grow two new dma_unmap and set_kvm methods.

This will isolate the drives from the whole notifiers mess and it's
boilerplate code.