sh/mm: enable ARCH_HAS_VM_GET_PAGE_PROT

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.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Anshuman Khandual <[e-mail]>
Cc: Yoshinori Sato <[e-mail]>
Cc: Rich Felker <[e-mail]>
Cc: Arnd Bergmann <[e-mail]>
Cc: Brian Cain <[e-mail]>
Cc: Catalin Marinas <[e-mail]>
Cc: Christophe Leroy <[e-mail]>
Cc: Christoph Hellwig <[e-mail]>
Cc: Christoph Hellwig <[e-mail]>
Cc: Chris Zankel <[e-mail]>
Cc: "David S. Miller" <[e-mail]>
Cc: Dinh Nguyen <[e-mail]>
Cc: Geert Uytterhoeven <[e-mail]>
Cc: Guo Ren <[e-mail]>
Cc: Heiko Carstens <[e-mail]>
Cc: Huacai Chen <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: "James E.J. Bottomley" <[e-mail]>
Cc: Jeff Dike <[e-mail]>
Cc: Jonas Bonn <[e-mail]>
Cc: Michael Ellerman <[e-mail]>
Cc: Michal Simek <[e-mail]>
Cc: Nicholas Piggin <[e-mail]>
Cc: Palmer Dabbelt <[e-mail]>
Cc: Paul Mackerras <[e-mail]>
Cc: Paul Walmsley <[e-mail]>
Cc: Richard Henderson <[e-mail]>
Cc: Russell King <[e-mail]>
Cc: Sam Ravnborg <[e-mail]>
Cc: Stafford Horne <[e-mail]>
Cc: Thomas Bogendoerfer <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Vasily Gorbik <[e-mail]>
Cc: Vineet Gupta <[e-mail]>
Cc: WANG Xuerui <[e-mail]>
Cc: Will Deacon <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

arch/sh/Kconfig

···
 	select ARCH_HAS_GCOV_PROFILE_ALL
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
+	select ARCH_HAS_VM_GET_PAGE_PROT
 	select ARCH_HIBERNATION_POSSIBLE if MMU
 	select ARCH_MIGHT_HAVE_PC_PARPORT
 	select ARCH_WANT_IPC_PARSE_VERSION

arch/sh/include/asm/pgtable.h

···
  * completely separate permission bits for user and kernel space.
  */
 	 /*xwr*/
-#define __P000	PAGE_NONE
-#define __P001	PAGE_READONLY
-#define __P010	PAGE_COPY
-#define __P011	PAGE_COPY
-#define __P100	PAGE_EXECREAD
-#define __P101	PAGE_EXECREAD
-#define __P110	PAGE_COPY
-#define __P111	PAGE_COPY
-
-#define __S000	PAGE_NONE
-#define __S001	PAGE_READONLY
-#define __S010	PAGE_WRITEONLY
-#define __S011	PAGE_SHARED
-#define __S100	PAGE_EXECREAD
-#define __S101	PAGE_EXECREAD
-#define __S110	PAGE_RWX
-#define __S111	PAGE_RWX
 
 typedef pte_t *pte_addr_t;
 

arch/sh/mm/mmap.c

···
 EXPORT_SYMBOL(shm_align_mask);
 
 #ifdef CONFIG_MMU
+static const pgprot_t protection_map[16] = {
+	[VM_NONE]					= PAGE_NONE,
+	[VM_READ]					= PAGE_READONLY,
+	[VM_WRITE]					= PAGE_COPY,
+	[VM_WRITE | VM_READ]				= PAGE_COPY,
+	[VM_EXEC]					= PAGE_EXECREAD,
+	[VM_EXEC | VM_READ]				= PAGE_EXECREAD,
+	[VM_EXEC | VM_WRITE]				= PAGE_COPY,
+	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_COPY,
+	[VM_SHARED]					= PAGE_NONE,
+	[VM_SHARED | VM_READ]				= PAGE_READONLY,
+	[VM_SHARED | VM_WRITE]				= PAGE_WRITEONLY,
+	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_SHARED,
+	[VM_SHARED | VM_EXEC]				= PAGE_EXECREAD,
+	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_EXECREAD,
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_RWX,
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_RWX
+};
+DECLARE_VM_GET_PAGE_PROT
+
 /*
  * To avoid cache aliases, we map the shared page with same color.
  */