[PATCH v2] nvmet: pci-epf: Always configure BAR0 as 64-bit

[Keith Busch]

On Mon, Mar 17, 2025 at 10:57:04AM +0100, Niklas Cassel wrote:
> NVMe PCIe Transport Specification 1.1, section 2.1.10, claims that the
> BAR0 type is Implementation Specific.
> 
> However, in NVMe 1.1, the type is required to be 64-bit.
> 
> Thus, to make our PCI EPF work on as many host systems as possible,
> always configure the BAR0 type to be 64-bit.
> 
> In the rare case that the underlying PCI EPC does not support configuring
> BAR0 as 64-bit, the call to pci_epc_set_bar() will fail, and we will
> return a failure back to the user.
> 
> This should not be a problem, as most PCI EPCs support configuring a BAR
> as 64-bit (and those EPCs with .only_64bit set to true in epc_features
> only support configuring the BAR as 64-bit).

Thanks, applied to nvme-6.15.