[PATCH 1/3] mm: introduce ARCH_HAS_PTE_SPECIAL

From: Laurent Dufour
Date: Mon Apr 09 2018 - 09:57:43 EST


Currently the PTE special supports is turned on in per architecture header
files. Most of the time, it is defined in arch/*/include/asm/pgtable.h
depending or not on some other per architecture static definition.

This patch introduce a new configuration variable to manage this directly
in the Kconfig files. It would later replace __HAVE_ARCH_PTE_SPECIAL.

Here notes for some architecture where the definition of
__HAVE_ARCH_PTE_SPECIAL is not obvious:

arm
__HAVE_ARCH_PTE_SPECIAL which is currently defined in
arch/arm/include/asm/pgtable-3level.h which is included by
arch/arm/include/asm/pgtable.h when CONFIG_ARM_LPAE is set.
So select ARCH_HAS_PTE_SPECIAL if ARM_LPAE.

powerpc
__HAVE_ARCH_PTE_SPECIAL is defined in 2 files:
- arch/powerpc/include/asm/book3s/64/pgtable.h
- arch/powerpc/include/asm/pte-common.h
The first one is included if (PPC_BOOK3S & PPC64) while the second is
included in all the other cases.
So select ARCH_HAS_PTE_SPECIAL all the time.

sparc:
__HAVE_ARCH_PTE_SPECIAL is defined if defined(__sparc__) &&
defined(__arch64__) which are defined through the compiler in
sparc/Makefile if !SPARC32 which I assume to be if SPARC64.
So select ARCH_HAS_PTE_SPECIAL if SPARC64

Suggested-by: Jerome Glisse <jglisse@xxxxxxxxxx>
Signed-off-by: Laurent Dufour <ldufour@xxxxxxxxxxxxxxxxxx>
---
arch/arc/Kconfig | 1 +
arch/arm/Kconfig | 1 +
arch/arm64/Kconfig | 1 +
arch/powerpc/Kconfig | 1 +
arch/riscv/Kconfig | 1 +
arch/s390/Kconfig | 1 +
arch/sh/Kconfig | 1 +
arch/sparc/Kconfig | 1 +
arch/x86/Kconfig | 1 +
mm/Kconfig | 3 +++
10 files changed, 12 insertions(+)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index d76bf4a83740..8516e2b0239a 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -44,6 +44,7 @@ config ARC
select HAVE_GENERIC_DMA_COHERENT
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZMA
+ select ARCH_HAS_PTE_SPECIAL

config MIGHT_HAVE_PCI
bool
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 1878083771af..a67973cb041c 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -7,6 +7,7 @@ config ARM
select ARCH_HAS_DEBUG_VIRTUAL if MMU
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_HAS_ELF_RANDOMIZE
+ select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
select ARCH_HAS_SET_MEMORY
select ARCH_HAS_PHYS_TO_DMA
select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 276e96ceaf27..7ae3c09921fb 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -17,6 +17,7 @@ config ARM64
select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
select ARCH_HAS_KCOV
select ARCH_HAS_MEMBARRIER_SYNC_CORE
+ select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_SET_MEMORY
select ARCH_HAS_SG_CHAIN
select ARCH_HAS_STRICT_KERNEL_RWX
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index c32a181a7cbb..f7415fe25c07 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -141,6 +141,7 @@ config PPC
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_HAS_PHYS_TO_DMA
select ARCH_HAS_PMEM_API if PPC64
+ select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_MEMBARRIER_CALLBACKS
select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE
select ARCH_HAS_SG_CHAIN
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 148865de1692..b0a8404bf684 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -34,6 +34,7 @@ config RISCV
select THREAD_INFO_IN_TASK
select RISCV_TIMER
select GENERIC_IRQ_MULTI_HANDLER
+ select ARCH_HAS_PTE_SPECIAL

config MMU
def_bool y
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 32a0d5b958bf..5f1f4997e7e9 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -72,6 +72,7 @@ config S390
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
select ARCH_HAS_KCOV
+ select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_SET_MEMORY
select ARCH_HAS_SG_CHAIN
select ARCH_HAS_STRICT_KERNEL_RWX
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 97fe29316476..a6c75b6806d2 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -50,6 +50,7 @@ config SUPERH
select HAVE_ARCH_AUDITSYSCALL
select HAVE_FUTEX_CMPXCHG if FUTEX
select HAVE_NMI
+ select ARCH_HAS_PTE_SPECIAL
help
The SuperH is a RISC processor targeted for use in embedded systems
and consumer electronics; it was also used in the Sega Dreamcast
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 8767e45f1b2b..6b5a4f05dcb2 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -86,6 +86,7 @@ config SPARC64
select ARCH_USE_QUEUED_SPINLOCKS
select GENERIC_TIME_VSYSCALL
select ARCH_CLOCKSOURCE_DATA
+ select ARCH_HAS_PTE_SPECIAL

config ARCH_DEFCONFIG
string
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index bf4ddea48e61..3f5fb25486bf 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -56,6 +56,7 @@ config X86
select ARCH_HAS_KCOV if X86_64
select ARCH_HAS_MEMBARRIER_SYNC_CORE
select ARCH_HAS_PMEM_API if X86_64
+ select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_REFCOUNT
select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
select ARCH_HAS_SET_MEMORY
diff --git a/mm/Kconfig b/mm/Kconfig
index bf9d6366bced..60ae67b83e62 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -757,3 +757,6 @@ config GUP_BENCHMARK
performance of get_user_pages_fast().

See tools/testing/selftests/vm/gup_benchmark.c
+
+config ARCH_HAS_PTE_SPECIAL
+ bool
--
2.7.4