parisc/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/20220711070600.2378316-14-anshuman.khandual@arm.comSigned-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/parisc/Kconfig

@@ -12,6 +12,7 @@ config PARISC
 	select ARCH_HAS_STRICT_KERNEL_RWX
 	select ARCH_HAS_STRICT_MODULE_RWX
 	select ARCH_HAS_UBSAN_SANITIZE_ALL
+	select ARCH_HAS_VM_GET_PAGE_PROT
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_NO_SG_CHAIN
 	select ARCH_SUPPORTS_HUGETLBFS if PA20

arch/parisc/include/asm/pgtable.h

@@ -271,24 +271,6 @@ extern void __update_cache(pte_t pte);
  */
 
 	 /*xwr*/
-#define __P000  PAGE_NONE
-#define __P001  PAGE_READONLY
-#define __P010  __P000 /* copy on write */
-#define __P011  __P001 /* copy on write */
-#define __P100  PAGE_EXECREAD
-#define __P101  PAGE_EXECREAD
-#define __P110  __P100 /* copy on write */
-#define __P111  __P101 /* copy on write */
-
-#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
-
 
 extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
 

arch/parisc/mm/init.c

@@ -871,3 +871,23 @@ void flush_tlb_all(void)
 	spin_unlock(&sid_lock);
 }
 #endif
+
+static const pgprot_t protection_map[16] = {
+	[VM_NONE]					= PAGE_NONE,
+	[VM_READ]					= PAGE_READONLY,
+	[VM_WRITE]					= PAGE_NONE,
+	[VM_WRITE | VM_READ]				= PAGE_READONLY,
+	[VM_EXEC]					= PAGE_EXECREAD,
+	[VM_EXEC | VM_READ]				= PAGE_EXECREAD,
+	[VM_EXEC | VM_WRITE]				= PAGE_EXECREAD,
+	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_EXECREAD,
+	[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