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From:   Logan Gunthorpe <logang@deltatee.com>
Message-ID: <805645c1-ea40-2e57-88eb-5dd34e579b2e@deltatee.com>
Date:   Wed, 2 May 2018 09:56:09 -0600
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Subject: Re: [PATCH v4 00/14] Copy Offload in NVMe Fabrics with P2P PCI Memory
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Hi Christian,

On 5/2/2018 5:51 AM, Christian König wrote:
> it would be rather nice to have if you could separate out the functions 
> to detect if peer2peer is possible between two devices.

This would essentially be pci_p2pdma_distance() in the existing 
patchset. It returns the sum of the distance between a list of clients 
and a P2PDMA provider. It returns -1 if peer2peer is not possible 
between the devices (presently this means they are not behind the same 
root port).

Logan