[PATCH V4 11/26] extensa/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT

[Anshuman Khandual]

This enables ARCH_HAS_VM_GET_PAGE_PROT on the platform and exports standard
vm_get_page_prot() implementation via DECLARE_VM_GET_PAGE_PROT, which looks
up a private and static protection_map[] array. Subsequently all __SXXX and
__PXXX macros can be dropped which are no longer needed.

Cc: Chris Zankel <chris@xxxxxxxxxx>
Cc: Guo Ren <guoren@xxxxxxxxxx>
Cc: linux-xtensa@xxxxxxxxxxxxxxxx
Cc: linux-csky@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
 arch/xtensa/Kconfig               |  1 +
 arch/xtensa/include/asm/pgtable.h | 18 ------------------
 arch/xtensa/mm/init.c             | 20 ++++++++++++++++++++
 3 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 0b0f0172cced..4c0d83520ff1 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -11,6 +11,7 @@ config XTENSA
 	select ARCH_HAS_DMA_SET_UNCACHED if MMU
 	select ARCH_HAS_STRNCPY_FROM_USER if !KASAN
 	select ARCH_HAS_STRNLEN_USER
+	select ARCH_HAS_VM_GET_PAGE_PROT
 	select ARCH_USE_MEMTEST
 	select ARCH_USE_QUEUED_RWLOCKS
 	select ARCH_USE_QUEUED_SPINLOCKS
diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
index 0a91376131c5..e0d5531ae00d 100644
--- a/arch/xtensa/include/asm/pgtable.h
+++ b/arch/xtensa/include/asm/pgtable.h
@@ -200,24 +200,6 @@
  * What follows is the closest we can get by reasonable means..
  * See linux/mm/mmap.c for protection_map[] array that uses these definitions.
  */
-#define __P000	PAGE_NONE		/* private --- */
-#define __P001	PAGE_READONLY		/* private --r */
-#define __P010	PAGE_COPY		/* private -w- */
-#define __P011	PAGE_COPY		/* private -wr */
-#define __P100	PAGE_READONLY_EXEC	/* private x-- */
-#define __P101	PAGE_READONLY_EXEC	/* private x-r */
-#define __P110	PAGE_COPY_EXEC		/* private xw- */
-#define __P111	PAGE_COPY_EXEC		/* private xwr */
-
-#define __S000	PAGE_NONE		/* shared  --- */
-#define __S001	PAGE_READONLY		/* shared  --r */
-#define __S010	PAGE_SHARED		/* shared  -w- */
-#define __S011	PAGE_SHARED		/* shared  -wr */
-#define __S100	PAGE_READONLY_EXEC	/* shared  x-- */
-#define __S101	PAGE_READONLY_EXEC	/* shared  x-r */
-#define __S110	PAGE_SHARED_EXEC	/* shared  xw- */
-#define __S111	PAGE_SHARED_EXEC	/* shared  xwr */
-
 #ifndef __ASSEMBLY__
 
 #define pte_ERROR(e) \
diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c
index 6a32b2cf2718..7d5ac1b049c3 100644
--- a/arch/xtensa/mm/init.c
+++ b/arch/xtensa/mm/init.c
@@ -216,3 +216,23 @@ static int __init parse_memmap_opt(char *str)
 	return 0;
 }
 early_param("memmap", parse_memmap_opt);
+
+static 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_EXEC,
+	[VM_EXEC | VM_READ]				= PAGE_READONLY_EXEC,
+	[VM_EXEC | VM_WRITE]				= PAGE_COPY_EXEC,
+	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_COPY_EXEC,
+	[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_EXEC,
+	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_READONLY_EXEC,
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_SHARED_EXEC,
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_SHARED_EXEC
+};
+DECLARE_VM_GET_PAGE_PROT
-- 
2.25.1