Re: [PATCH v2 00/27] PCI resource mmap cleanup

[Bjorn Helgaas]

On Tue, Apr 18, 2017 at 01:28:16PM -0500, Bjorn Helgaas wrote:
> On Wed, Apr 12, 2017 at 01:25:49PM +0100, David Woodhouse wrote:
> > This pursues my previous patch set all the way to its logical conclusion.
> > 
> > It kills off the legacy arch-provided pci_mmap_page_range() completely,
> > along with its vile 'address converted by pci_resource_to_user()' API
> > and the various bugs and other strange behaviour that various
> > architectures had.
> > 
> > In some cases like IA64 I've killed off the odd behaviour *first* in
> > separately reviewable patches, before the final switch over to the
> > generic code which should then basically have no functional effect.
> > 
> > To accommodate the ARM64 maintainers' desire *not* to support mmap
> > through /proc/bus/pci I have separated HAVE_PCI_MMAP from the sysfs
> > implementation, which (as of the last patch in the series) ends up
> > present on *all* platforms with an MMU. I still don't think that's a
> > *good* idea though; it's a generic part of /proc, and nobody ever did
> > answer my question about what *else* we can delete from /proc on ARM64
> > "because it's a new platform"...
> > 
> > I would very much like the interesting parts of this to go through the
> > arch maintainers' trees. I'd suggest that we can pull everything up to
> > and including patch 19 ("pci: Add I/O BAR support to generic
> > pci_mmap_resource_range()") through the PCI tree, which includes the
> > relatively trivial architectures. Then the others can go through the
> > appropriate arch tree with more careful review and testing.
> > 
> > Once everything's done, then we can apply something like the final
> > patch ("pci: Kill ARCH_GENERIC_PCI_MMAP_RESOURCE"). But that's mostly
> > just there for now as a demonstration of the intended end point.
> > 
> > This is in
> >  git://git.infradead.org/users/dwmw2/random-2.6.git pcimmap
> >  http://git.infradead.org/users/dwmw2/random-2.6.git/shortlog/refs/heads/pcimmap
> 
> Applied to pci/resource-mmap for v4.12, thanks!
> 
> This consists of the email patches + the acks/etc so far.  It doesn't
> include any updates from your git branch (but it doesn't look like it's
> been updated recently).

Oops, sorry, I just noticed your desired merge process above.

I removed everything after patch 19 from my branch, so it now contains
these patches:

  e34bedcbfa71 PCI: Add I/O BAR support to generic pci_mmap_resource_range()
  4f27eb90214b x86/PCI: Use generic pci_mmap_resource_range()
  192702a91cdc unicore32/PCI: Use generic pci_mmap_resource_range()
  11c9d07f5a48 sh/PCI: Use generic pci_mmap_resource_range()
  c18dc595e36c parisc: Use generic pci_mmap_resource_range()
  f8773c830087 mn10300/PCI: Use generic pci_mmap_resource_range()
  93ec50f6955d MIPS: PCI: Use generic pci_mmap_resource_range()
  e47765a11a38 cris/PCI: Use generic pci_mmap_resource_range()
  a2f4dd2b148b ARM/PCI: Use generic pci_mmap_resource_range()
  9f97f5c8fb0e PCI: Add pci_mmap_resource_range() and use it for ARM64
  4536661783d8 PCI: Add BAR index argument to pci_mmap_page_range()
  3e07a66fe61c PCI: Use BAR index in sysfs attr->private instead of resource pointer
  416a332dcf00 pci: Add arch_can_pci_mmap_io() on architectures which can mmap() I/O space
  11df19546fe4 PCI: Move multiple declarations of pci_mmap_page_range() to <linux/pci.h>
  ae749c7ab475 PCI: Add arch_can_pci_mmap_wc() macro
  03a064b431eb xtensa/PCI: Do not mmap PCI BARs to userspace as write-through
  cef4d02305a0 PCI: Only allow WC mmap on prefetchable resources
  17caf5673131 PCI: Fix another sanity check bug in /proc/pci mmap
  6bccc7f426ab PCI: Fix pci_mmap_fits() for HAVE_PCI_RESOURCE_TO_USER platforms

> > David Woodhouse (27):
> >   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
> >   xtensa: Do not mmap PCI BARs to userspace as write-through
> >   pci: Add arch_can_pci_mmap_wc() macro
> >   pci: Move multiple declarations of pci_mmap_page_range() to
> >     <linux/pci.h>
> >   pci: Add arch_can_pci_mmap_io() on 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()
> >   x86: Use generic pci_mmap_resource_range()
> >   pci: Add I/O BAR support to generic pci_mmap_resource_range()
> >   powerpc: Use generic pci_mmap_resource_range()
> >   microblaze: Use generic pci_mmap_resource_range()
> >   xtensa: Use generic pci_mmap_resource_range()
> >   ia64: Remove redundant valid_mmap_phys_addr_range() from
> >     pci_mmap_page_range()
> >   ia64: Remove redundant checks for WC in pci_mmap_page_range()
> >   ia64: Use generic pci_mmap_resource_range()
> >   sparc: Use generic pci_mmap_resource_range()
> >   pci: Kill ARCH_GENERIC_PCI_MMAP_RESOURCE
> > 
> >  Documentation/filesystems/sysfs-pci.txt |  12 ++-
> >  arch/arm/include/asm/pci.h              |   2 -
> >  arch/arm/kernel/bios32.c                |  19 ----
> >  arch/cris/arch-v32/drivers/pci/bios.c   |  22 -----
> >  arch/cris/include/asm/pci.h             |   3 -
> >  arch/ia64/include/asm/pci.h             |   4 +-
> >  arch/ia64/pci/pci.c                     |  46 ----------
> >  arch/microblaze/include/asm/pci.h       |   8 +-
> >  arch/microblaze/pci/pci-common.c        |  99 ++------------------
> >  arch/mips/include/asm/pci.h             |   4 -
> >  arch/mips/pci/pci.c                     |  24 -----
> >  arch/mn10300/include/asm/pci.h          |   3 -
> >  arch/mn10300/unit-asb2305/pci-asb2305.c |  23 -----
> >  arch/parisc/include/asm/pci.h           |   3 -
> >  arch/parisc/kernel/pci.c                |  28 ------
> >  arch/powerpc/include/asm/pci.h          |   9 +-
> >  arch/powerpc/kernel/pci-common.c        | 105 +++-------------------
> >  arch/sh/drivers/pci/pci.c               |  21 -----
> >  arch/sh/include/asm/pci.h               |   3 +-
> >  arch/sparc/include/asm/pci_64.h         |   5 +-
> >  arch/sparc/kernel/pci.c                 | 155 --------------------------------
> >  arch/unicore32/include/asm/pci.h        |   2 -
> >  arch/unicore32/kernel/pci.c             |  23 -----
> >  arch/x86/include/asm/pci.h              |   6 +-
> >  arch/x86/pci/i386.c                     |  47 ----------
> >  arch/xtensa/include/asm/pci.h           |   9 +-
> >  arch/xtensa/kernel/pci.c                | 112 ++---------------------
> >  drivers/pci/Makefile                    |   1 +
> >  drivers/pci/mmap.c                      |  67 ++++++++++++++
> >  drivers/pci/pci-sysfs.c                 |  76 +++++++---------
> >  drivers/pci/pci.h                       |   4 +-
> >  drivers/pci/proc.c                      |  41 ++++++---
> >  include/linux/pci.h                     |  30 +++++++
> >  33 files changed, 211 insertions(+), 805 deletions(-)
> >  create mode 100644 drivers/pci/mmap.c
> > 
> > -- 
> > 2.9.3
> >