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Date:   Thu, 14 Jun 2018 06:33:41 -0400
From:   okaya@codeaurora.org
To:     Srinath Mannam <srinath.mannam@broadcom.com>
Cc:     Christoph Hellwig <hch@lst.de>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Abhishek Shah <abhishek.shah@broadcom.com>,
        Vikram Prakash <vikram.prakash@broadcom.com>,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-nvme@lists.infradead.org,
        Alex Williamson <alex.williamson@redhat.com>,
        kvm@vger.kernel.org, linux-pci-owner@vger.kernel.org
Subject: Re: Requirement to get BAR pci_bus_address in user space
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On 2018-06-14 06:29, Srinath Mannam wrote:
> ++ Alex Williamson, kvm,
> 
> Hi Christoph,
> 
> Thank you for quick reply.
> 
> If we want to add this in vfio then I think we need to do the same in
> uio case also.
> 
> As I mentioned in previous mail, in the current implementation
> resource information (address and size) is gathering from resource
> named file created in /sys directory.
> So I expect it would be better to have similar method as existing in 
> sysfs.
> 

Can you give some info on why you need the actual bar address value?

> 
> Regards,
> Srinath.
> 
> On Thu, Jun 14, 2018 at 3:50 PM, Christoph Hellwig <hch@lst.de> wrote:
>> The only safe way to use PCI(e) devices in userspace is through vfio.
>> I think that is where you need to take your inquiries.