Currently there are many platforms that dont enable ARCH_HAS_PTE_SPECIAL
but required to define quite similar fallback stubs for special page
table entry helpers such as pte_special() and pte_mkspecial(), as they
get build in generic MM without a config check.  This creates two
generic fallback stub definitions for these helpers, eliminating much
code duplication.

mips platform has a special case where pte_special() and pte_mkspecial()
visibility is wider than what ARCH_HAS_PTE_SPECIAL enablement requires.
This restricts those symbol visibility in order to avoid redefinitions
which is now exposed through this new generic stubs and subsequent build
failure.  arm platform set_pte_at() definition needs to be moved into a
C file just to prevent a build failure.

[anshuman.khandual@arm.com: use defined(CONFIG_ARCH_HAS_PTE_SPECIAL) in mips per Thomas]
  Link: http://lkml.kernel.org/r/1583851924-21603-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Guo Ren <guoren@kernel.org>			[csky]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Acked-by: Stafford Horne <shorne@gmail.com>		[openrisc]
Acked-by: Helge Deller <deller@gmx.de>			[parisc]
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Link: http://lkml.kernel.org/r/1583802551-15406-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS
This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the
existing VM_STACK_DEFAULT_FLAGS.  While here, also define some more
macros with standard VMA access flag combinations that are used
frequently across many platforms.  Apart from simplification, this
reduces code duplication as well.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull irq fixes from Thomas Gleixner:
 "Two reverts addressing regressions of the Xilinx interrupt controller
  driver which affected the PPC users"

* tag 'irq-urgent-2020-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "irqchip/xilinx: Enable generic irq multi handler"
  Revert "irqchip/xilinx: Do not call irq_set_default_host()"

Change a header to mandatory-y if both of the following are met:

[1] At least one architecture (except um) specifies it as generic-y in
    arch/*/include/asm/Kbuild

[2] Every architecture (except um) either has its own implementation
    (arch/*/include/asm/*.h) or specifies it as generic-y in
    arch/*/include/asm/Kbuild

This commit was generated by the following shell script.

----------------------------------->8-----------------------------------

arches=$(cd arch; ls -1 | sed -e '/Kconfig/d' -e '/um/d')

tmpfile=$(mktemp)

grep "^mandatory-y +=" include/asm-generic/Kbuild > $tmpfile

find arch -path 'arch/*/include/asm/Kbuild' |
	xargs sed -n 's/^generic-y += \(.*\)/\1/p' | sort -u |
while read header
do
	mandatory=yes

	for arch in $arches
	do
		if ! grep -q "generic-y += $header" arch/$arch/include/asm/Kbuild &&
			! [ -f arch/$arch/include/asm/$header ]; then
			mandatory=no
			break
		fi
	done

	if [ "$mandatory" = yes ]; then
		echo "mandatory-y += $header" >> $tmpfile

		for arch in $arches
		do
			sed -i "/generic-y += $header/d" arch/$arch/include/asm/Kbuild
		done
	fi

done

sed -i '/^mandatory-y +=/d' include/asm-generic/Kbuild

LANG=C sort $tmpfile >> include/asm-generic/Kbuild

----------------------------------->8-----------------------------------

One obvious benefit is the diff stat:

 25 files changed, 52 insertions(+), 557 deletions(-)

It is tedious to list generic-y for each arch that needs it.

So, mandatory-y works like a fallback default (by just wrapping
asm-generic one) when arch does not have a specific header
implementation.

See the following commits:

def3f7cefe4e81c296090e1722a76551142c227c
a1b39bae16a62ce4aae02d958224f19316d98b24

It is tedious to convert headers one by one, so I processed by a shell
script.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: http://lkml.kernel.org/r/20200210175452.5030-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull irqchip fixes from Marc Zygnier:

 - Partially revert Xilinx changes that break PPC systems

This reverts commit a0789993bf8266e62fea6b4613945ba081c71e7d, which
breaks a number of PPC platforms.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/44b64be7-9240-fd52-af90-e0245220f38b@xilinx.com

Pull microblaze updates from Michal Simek:

 - convert license headers to SPDX

 - cleanup header handling and use asm-generic one

 - get rid of earlyprintk residues

 - define barriers and use it in the code

 - get rid of setup_irq() for timer

 - various small addons and fixes

* tag 'microblaze-v5.7-rc1' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze: Replace setup_irq() by request_irq()
  microblaze: Stop printing the virtual memory layout
  microblaze: Use asm generic cmpxchg.h for !SMP case
  microblaze: Define percpu sestion in linker file
  microblaze: Remove unused boot_cpuid variable
  microblaze: Add missing irqflags.h header
  microblaze: Add sync to tlb operations
  microblaze: Define microblaze barrier
  microblaze: Remove empty headers
  microblaze: Remove early printk setup
  microblaze: Remove architecture tlb.h and use generic one
  microblaze: Convert headers to SPDX license
  microblaze: Fix _reset() function
  microblaze: Kernel parameters should be parsed earlier

Pull irq updates from Thomas Gleixner:
 "Updates for the interrupt subsystem:

  Treewide:

    - Cleanup of setup_irq() which is not longer required because the
      memory allocator is available early.

      Most cleanup changes come through the various maintainer trees, so
      the final removal of setup_irq() is postponed towards the end of
      the merge window.

  Core:

    - Protection against unsafe invocation of interrupt handlers and
      unsafe interrupt injection including a fixup of the offending
      PCI/AER error injection mechanism.

      Invoking interrupt handlers from arbitrary contexts, i.e. outside
      of an actual interrupt, can cause inconsistent state on the
      fragile x86 interrupt affinity changing hardware trainwreck.

  Drivers:

    - Second wave of support for the new ARM GICv4.1

    - Multi-instance support for Xilinx and PLIC interrupt controllers

    - CPU-Hotplug support for PLIC

    - The obligatory new driver for X1000 TCU

    - Enhancements, cleanups and fixes all over the place"

* tag 'irq-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
  unicore32: Replace setup_irq() by request_irq()
  sh: Replace setup_irq() by request_irq()
  hexagon: Replace setup_irq() by request_irq()
  c6x: Replace setup_irq() by request_irq()
  alpha: Replace setup_irq() by request_irq()
  irqchip/gic-v4.1: Eagerly vmap vPEs
  irqchip/gic-v4.1: Add VSGI property setup
  irqchip/gic-v4.1: Add VSGI allocation/teardown
  irqchip/gic-v4.1: Move doorbell management to the GICv4 abstraction layer
  irqchip/gic-v4.1: Plumb set_vcpu_affinity SGI callbacks
  irqchip/gic-v4.1: Plumb get/set_irqchip_state SGI callbacks
  irqchip/gic-v4.1: Plumb mask/unmask SGI callbacks
  irqchip/gic-v4.1: Add initial SGI configuration
  irqchip/gic-v4.1: Plumb skeletal VSGI irqchip
  irqchip/stm32: Retrigger both in eoi and unmask callbacks
  irqchip/gic-v3: Move irq_domain_update_bus_token to after checking for NULL domain
  irqchip/xilinx: Do not call irq_set_default_host()
  irqchip/xilinx: Enable generic irq multi handler
  irqchip/xilinx: Fill error code when irq domain registration fails
  irqchip/xilinx: Add support for multiple instances
  ...

Pull uaccess futex cleanups for Al Viro:

     Consolidate access_ok() usage and the futex uaccess function zoo.

Move access_ok() in and pagefault_enable()/pagefault_disable() out.
Mechanical conversion only - some instances don't really need
a separate access_ok() at all (e.g. the ones only using
get_user()/put_user(), or architectures where access_ok()
is always true); we'll deal with that in followups.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>