Re: [PATCH v4 0/4] Support VFIO sparse mmap in PCI bus

[Thomas Monjalon <thomas@monjalon.net>]

31/05/2023 07:37, Miao Li:
> This series introduces a VFIO standard capability, called sparse
> mmap to PCI bus. In linux kernel, it's defined as
> VFIO_REGION_INFO_CAP_SPARSE_MMAP. Sparse mmap means instead of
> mmap whole BAR region into DPDK process, only mmap part of the
> BAR region after getting sparse mmap information from kernel.
> For the rest of BAR region that is not mmap-ed, DPDK process
> can use pread/pwrite system calls to access. Sparse mmap is
> useful when kernel does not want userspace to mmap whole BAR
> region, or kernel wants to control over access to specific BAR
> region. Vendors can choose to enable this feature or not for
> their devices in their specific kernel modules.
> 
> In this patchset:
> 
> Patch 1-3 is mainly for introducing BAR access APIs so that
> driver could use them to access specific BAR using pread/pwrite
> system calls when part of the BAR is not mmap-able. Patch 4
> adds the VFIO sparse mmap support finally.
> 
> v4:
> 1. add sparse mmap information allocation and release
> 2. add release note for BAR access APIs
> 
> v3:
> fix variable 'pdev' and 'info' uninitialized error
> 
> v2:
> 1. add PCI device internal structure in bus/pci/windows/pci.c
> 2. fix parameter type error
> 
> Chenbo Xia (3):
>   bus/pci: introduce an internal representation of PCI device
>   bus/pci: avoid depending on private value in kernel source
>   bus/pci: introduce helper for MMIO read and write
> 
> Miao Li (1):
>   bus/pci: add VFIO sparse mmap support

Applied, thanks.

Is there some drivers which may reuse the new MMIO helpers?