[PATCH V4 03/26] powerpc/mm: Move protection_map[] inside the platform

Anshuman Khandual
2022-06-24T04:44:39Z

This moves protection_map[] inside the platform and while here, also enable
ARCH_HAS_VM_GET_PAGE_PROT on 32 bit platforms via DECLARE_VM_GET_PAGE_PROT.

Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
arch/powerpc/Kconfig | 2 +-
arch/powerpc/include/asm/pgtable.h | 20 +-------------------
arch/powerpc/mm/pgtable.c | 24 ++++++++++++++++++++++++
3 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index c2ce2e60c8f0..1035d172c7dd 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -140,7 +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_HAS_VM_GET_PAGE_PROT
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_KEEP_MEMBLOCK
select ARCH_MIGHT_HAVE_PC_PARPORT
diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
index d564d0ecd4cd..bf98db844579 100644
--- a/arch/powerpc/include/asm/pgtable.h
+++ b/arch/powerpc/include/asm/pgtable.h
@@ -20,25 +20,6 @@ struct mm_struct;
#include <asm/nohash/pgtable.h>
#endif /* !CONFIG_PPC_BOOK3S */

-/* Note due to the way vm flags are laid out, the bits are XWR */
-#define __P000 PAGE_NONE
-#define __P001 PAGE_READONLY
-#define __P010 PAGE_COPY
-#define __P011 PAGE_COPY
-#define __P100 PAGE_READONLY_X
-#define __P101 PAGE_READONLY_X
-#define __P110 PAGE_COPY_X
-#define __P111 PAGE_COPY_X
-
-#define __S000 PAGE_NONE
-#define __S001 PAGE_READONLY
-#define __S010 PAGE_SHARED
-#define __S011 PAGE_SHARED
-#define __S100 PAGE_READONLY_X
-#define __S101 PAGE_READONLY_X
-#define __S110 PAGE_SHARED_X
-#define __S111 PAGE_SHARED_X
-
#ifndef __ASSEMBLY__

#ifndef MAX_PTRS_PER_PGD
@@ -79,6 +60,7 @@ extern void paging_init(void);
void poking_init(void);

extern unsigned long ioremap_bot;
+extern pgprot_t protection_map[16] __ro_after_init;

/*
* kern_addr_valid is intended to indicate whether an address is a valid
diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index e6166b71d36d..618f30d35b17 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -472,3 +472,27 @@ pte_t *__find_linux_pte(pgd_t *pgdir, unsigned long ea,
return ret_pte;
}
EXPORT_SYMBOL_GPL(__find_linux_pte);
+
+/* Note due to the way vm flags are laid out, the bits are XWR */
+pgprot_t protection_map[16] __ro_after_init = {
+ [VM_NONE] = PAGE_NONE,
+ [VM_READ] = PAGE_READONLY,
+ [VM_WRITE] = PAGE_COPY,
+ [VM_WRITE | VM_READ] = PAGE_COPY,
+ [VM_EXEC] = PAGE_READONLY_X,
+ [VM_EXEC | VM_READ] = PAGE_READONLY_X,
+ [VM_EXEC | VM_WRITE] = PAGE_COPY_X,
+ [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_X,
+ [VM_SHARED] = PAGE_NONE,
+ [VM_SHARED | VM_READ] = PAGE_READONLY,
+ [VM_SHARED | VM_WRITE] = PAGE_SHARED,
+ [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
+ [VM_SHARED | VM_EXEC] = PAGE_READONLY_X,
+ [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY_X,
+ [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_X,
+ [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_X
+};
+
+#ifndef CONFIG_PPC_BOOK3S_64
+DECLARE_VM_GET_PAGE_PROT
+#endif
--
2.25.1