On Tue, Feb 18, 2025 at 10:10:08PM +1100, Alexey Kardashevskiy wrote:
> Add another resource#d_enc to allow mapping MMIO as
> an encrypted/private region.
I guess this means a sysfs file. Document alongside the others.
> Unlike resourceN_wc, the node is added always as ability to
> map MMIO as private depends on negotiation with the TSM which
> happens quite late.
Match capitalization (subject) and wrap to fill 75 columns.
> +++ b/include/linux/pci.h
> @@ -2129,7 +2129,7 @@ pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
> */
> int pci_mmap_resource_range(struct pci_dev *dev, int bar,
> struct vm_area_struct *vma,
> - enum pci_mmap_state mmap_state, int write_combine);
> + enum pci_mmap_state mmap_state, int write_combine, int enc);
Wrap to fit in 80 columns.
>
> #ifndef arch_can_pci_mmap_wc
> #define arch_can_pci_mmap_wc() 0
> diff --git a/drivers/pci/mmap.c b/drivers/pci/mmap.c
> index 8da3347a95c4..4fd522aeb767 100644
> --- a/drivers/pci/mmap.c
> +++ b/drivers/pci/mmap.c
> @@ -23,7 +23,7 @@ static const struct vm_operations_struct pci_phys_vm_ops = {
>
> int pci_mmap_resource_range(struct pci_dev *pdev, int bar,
> struct vm_area_struct *vma,
> - enum pci_mmap_state mmap_state, int write_combine)
> + enum pci_mmap_state mmap_state, int write_combine, int enc)
Ditto.
> {
> unsigned long size;
> int ret;
> @@ -46,6 +46,15 @@ int pci_mmap_resource_range(struct pci_dev *pdev, int bar,
>
> vma->vm_ops = &pci_phys_vm_ops;
>
> + /*
> + * Calling remap_pfn_range() directly as io_remap_pfn_range()
> + * enforces shared mapping.
s/Calling/Call/
> + */
> + if (enc)
> + return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
> + vma->vm_end - vma->vm_start,
> + vma->vm_page_prot);
> +
> return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
> vma->vm_end - vma->vm_start,
> vma->vm_page_prot);
