Re: [PATCH 00/17] PCI resource mmap cleanup

From: Bjorn Helgaas
Date: Tue Apr 04 2017 - 18:44:04 EST


On Wed, Mar 22, 2017 at 01:25:14PM +0000, David Woodhouse wrote:
> This started out as a fairly trivial "add pci_mmap_page_range() for
> ARM64" patch. But pci_mmap_page_range() is a vile interface, taking
> "user visible" resource addresses converted with pci_resource_to_user()
> on those platforms unlucky enough to use that... and even in the *sane*
> sysfs-based mmap method, we convert through user addresses to call the
> platform-specific method.
>
> In most cases there's just no need for any of this crap. We can migrate
> most architectures to a generic implementation without much thought,
> and the few that aren't converted in this series can probably be added
> fairly easily too but need a little more arch-specific attention.
>
> Utterly untested for now; I'll do some testing while I deal with the
> inevitable bikeshedding.

This looks really nice; thanks a lot for doing this!

I agree with Arnd about the __aarch64__ ifdef in pci/proc.c; I'd rather get
rid of that if we can.

I think you had a couple other updates; can you post a v2 when you're done
with those?

> David Woodhouse (17):
> pci: Fix pci_mmap_fits() for HAVE_PCI_RESOURCE_TO_USER platforms
> pci: Fix another sanity check bug in /proc/pci mmap
> pci: Only allow WC mmap on prefetchable resources
> pci: Add arch_can_pci_mmap_wc() macro
> pci: Move multiple declarations of pci_mmap_page_range() to <linux/pci.h>
> pci: Add HAVE_PCI_MMAP_IO to architectures which can mmap() I/O space
> pci: Use BAR index in sysfs attr->private instead of resource pointer
> pci: Add BAR index argument to pci_mmap_page_range()
> pci: Add pci_mmap_resource_range() and use it for ARM64
> arm: Use generic pci_mmap_resource_range()
> cris: Use generic pci_mmap_resource_range()
> mips: Use generic pci_mmap_resource_range()
> mn10300: Use generic pci_mmap_resource_range()
> parisc: Use generic pci_mmap_resource_range()
> sh: Use generic pci_mmap_resource_range()
> unicore: Use generic pci_mmap_resource_range()
> arm64: Do not expose PCI mmap through procfs
>
> Documentation/filesystems/sysfs-pci.txt | 9 +++-
> arch/arm/include/asm/pci.h | 3 +-
> arch/arm/kernel/bios32.c | 19 -------
> arch/arm64/include/asm/pci.h | 3 ++
> arch/cris/arch-v32/drivers/pci/bios.c | 22 --------
> arch/cris/include/asm/pci.h | 4 +-
> arch/ia64/include/asm/pci.h | 4 +-
> arch/ia64/pci/pci.c | 3 +-
> arch/microblaze/include/asm/pci.h | 6 +--
> arch/microblaze/pci/pci-common.c | 2 +-
> arch/mips/include/asm/pci.h | 5 +-
> arch/mips/pci/pci.c | 24 ---------
> arch/mn10300/include/asm/pci.h | 4 +-
> arch/mn10300/unit-asb2305/pci-asb2305.c | 23 ---------
> arch/parisc/include/asm/pci.h | 4 +-
> arch/parisc/kernel/pci.c | 28 ----------
> arch/powerpc/include/asm/pci.h | 9 ++--
> arch/powerpc/kernel/pci-common.c | 3 +-
> arch/sh/drivers/pci/pci.c | 21 --------
> arch/sh/include/asm/pci.h | 4 +-
> arch/sparc/include/asm/pci_64.h | 5 +-
> arch/sparc/kernel/pci.c | 6 +--
> arch/unicore32/include/asm/pci.h | 3 +-
> arch/unicore32/kernel/pci.c | 23 ---------
> arch/x86/include/asm/pci.h | 6 +--
> arch/x86/pci/i386.c | 3 +-
> arch/xtensa/include/asm/pci.h | 11 ++--
> arch/xtensa/kernel/pci.c | 5 +-
> drivers/pci/Makefile | 2 +-
> drivers/pci/mmap.c | 90 +++++++++++++++++++++++++++++++++
> drivers/pci/pci-sysfs.c | 77 +++++++++++++---------------
> drivers/pci/proc.c | 55 ++++++++++++++------
> include/linux/pci.h | 19 +++++++
> 33 files changed, 233 insertions(+), 272 deletions(-)
> create mode 100644 drivers/pci/mmap.c
>
> --
> 2.9.3
>