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Date:   Fri, 12 Mar 2021 18:36:57 -0800
From:   Ira Weiny <ira.weiny@intel.com>
To:     Logan Gunthorpe <logang@deltatee.com>
Cc:     linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
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Subject: Re: [RFC PATCH v2 07/11] dma-mapping: Add flags to dma_map_ops to
 indicate PCI P2PDMA support
Message-ID: <20210313023657.GC3402637@iweiny-DESK2.sc.intel.com>
References: <20210311233142.7900-1-logang@deltatee.com>
 <20210311233142.7900-8-logang@deltatee.com>
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On Thu, Mar 11, 2021 at 04:31:37PM -0700, Logan Gunthorpe wrote:
 
> +int dma_pci_p2pdma_supported(struct device *dev)
   ^^^
  bool?

> +{
> +	const struct dma_map_ops *ops = get_dma_ops(dev);
> +
> +	return !ops || ops->flags & DMA_F_PCI_P2PDMA_SUPPORTED;

Is this logic correct?  I would have expected.

	return (ops && ops->flags & DMA_F_PCI_P2PDMA_SUPPORTED);

Ira