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Date: Mon, 27 Oct 2025 09:16:58 +0100
From: Christoph Hellwig <hch@lst.de>
To: Leon Romanovsky <leon@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	Keith Busch <kbusch@kernel.org>, Sagi Grimberg <sagi@grimberg.me>,
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-nvme@lists.infradead.org
Subject: Re: [PATCH v3 2/2] block-dma: properly take MMIO path
Message-ID: <20251027081658.GA15229@lst.de>
References: <20251027-block-with-mmio-v3-0-ac3370e1f7b7@nvidia.com> <20251027-block-with-mmio-v3-2-ac3370e1f7b7@nvidia.com> <20251027074922.GA14543@lst.de> <20251027075738.GF12554@unreal> <20251027081142.GG12554@unreal>
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On Mon, Oct 27, 2025 at 10:11:42AM +0200, Leon Romanovsky wrote:
> BTW, one can reorganize pci_p2pdma_map_type to make sure that
> PCI_P2PDMA_MAP_BUS_ADDR will be 2 and PCI_P2PDMA_MAP_THRU_HOST_BRIDGE
> will be 3, so it will be possible to take 2 bits per-type instead of 3.

Maybe.  I'd be happy to leave this as-is and then see if we can optimize
things once we grow more users.