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Date:   Wed, 29 Jun 2022 08:42:35 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Logan Gunthorpe <logang@deltatee.com>
Cc:     linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
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Subject: Re: [PATCH v7 11/21] RDMA/core: introduce
 ib_dma_pci_p2p_dma_supported()
Message-ID: <20220629064235.GK17234@lst.de>
References: <20220615161233.17527-1-logang@deltatee.com> <20220615161233.17527-12-logang@deltatee.com>
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On Wed, Jun 15, 2022 at 10:12:23AM -0600, Logan Gunthorpe wrote:
> Introduce the helper function ib_dma_pci_p2p_dma_supported() to check
> if a given ib_device can be used in P2PDMA transfers. This ensures
> the ib_device is not using virt_dma and also that the underlying
> dma_device supports P2PDMA.
> 
> Use the new helper in nvme-rdma to replace the existing check for
> ib_uses_virt_dma(). Adding the dma_pci_p2pdma_supported() check allows
> switching away from pci_p2pdma_[un]map_sg().
> 
> Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>