[PATCH V7 2/7] powerpc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT

From: Anshuman Khandual
Date: Thu Apr 14 2022 - 02:21:18 EST


This defines and exports a platform specific custom vm_get_page_prot() via
subscribing ARCH_HAS_VM_GET_PAGE_PROT. While here, this also localizes
arch_vm_get_page_prot() as __vm_get_page_prot() and moves it near
vm_get_page_prot().

Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/mman.h | 12 ------------
arch/powerpc/mm/book3s64/pgtable.c | 17 +++++++++++++++++
3 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 174edabb74fa..69e44358a235 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -140,6 +140,7 @@ config PPC
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_UACCESS_FLUSHCACHE
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_HAS_VM_GET_PAGE_PROT if PPC_BOOK3S_64
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_KEEP_MEMBLOCK
select ARCH_MIGHT_HAVE_PC_PARPORT
diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h
index 7cb6d18f5cd6..1b024e64c8ec 100644
--- a/arch/powerpc/include/asm/mman.h
+++ b/arch/powerpc/include/asm/mman.h
@@ -24,18 +24,6 @@ static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
}
#define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)

-static inline pgprot_t arch_vm_get_page_prot(unsigned long vm_flags)
-{
-#ifdef CONFIG_PPC_MEM_KEYS
- return (vm_flags & VM_SAO) ?
- __pgprot(_PAGE_SAO | vmflag_to_pte_pkey_bits(vm_flags)) :
- __pgprot(0 | vmflag_to_pte_pkey_bits(vm_flags));
-#else
- return (vm_flags & VM_SAO) ? __pgprot(_PAGE_SAO) : __pgprot(0);
-#endif
-}
-#define arch_vm_get_page_prot(vm_flags) arch_vm_get_page_prot(vm_flags)
-
static inline bool arch_validate_prot(unsigned long prot, unsigned long addr)
{
if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_SAO))
diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
index 052e6590f84f..8b474ab32f67 100644
--- a/arch/powerpc/mm/book3s64/pgtable.c
+++ b/arch/powerpc/mm/book3s64/pgtable.c
@@ -7,6 +7,7 @@
#include <linux/mm_types.h>
#include <linux/memblock.h>
#include <linux/memremap.h>
+#include <linux/pkeys.h>
#include <linux/debugfs.h>
#include <misc/cxl-base.h>

@@ -549,3 +550,19 @@ unsigned long memremap_compat_align(void)
}
EXPORT_SYMBOL_GPL(memremap_compat_align);
#endif
+
+pgprot_t vm_get_page_prot(unsigned long vm_flags)
+{
+ unsigned long prot = pgprot_val(protection_map[vm_flags &
+ (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]);
+
+ if (vm_flags & VM_SAO)
+ prot |= _PAGE_SAO;
+
+#ifdef CONFIG_PPC_MEM_KEYS
+ prot |= vmflag_to_pte_pkey_bits(vm_flags);
+#endif
+
+ return __pgprot(prot);
+}
+EXPORT_SYMBOL(vm_get_page_prot);
--
2.25.1