m68k/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/20220711070600.2378316-22-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
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: 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: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.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 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>

3 files changed, 104 insertions, 0 deletions

diff --git a/arch/m68k/mm/mcfmmu.c b/arch/m68k/mm/mcfmmu.c
index 6f1f25125294..70aa0979e027 100644
--- a/arch/m68k/mm/mcfmmu.c
+++ b/arch/m68k/mm/mcfmmu.c
@@ -234,3 +234,58 @@ void steal_context(void)
 	destroy_context(mm);
 }
 
+static const pgprot_t protection_map[16] = {
+	[VM_NONE]					= PAGE_NONE,
+	[VM_READ]					= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_READABLE),
+	[VM_WRITE]					= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_WRITABLE),
+	[VM_WRITE | VM_READ]				= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_READABLE |
+								   CF_PAGE_WRITABLE),
+	[VM_EXEC]					= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_EXEC),
+	[VM_EXEC | VM_READ]				= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_READABLE |
+								   CF_PAGE_EXEC),
+	[VM_EXEC | VM_WRITE]				= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_WRITABLE |
+								   CF_PAGE_EXEC),
+	[VM_EXEC | VM_WRITE | VM_READ]			=  __pgprot(CF_PAGE_VALID |
+								    CF_PAGE_ACCESSED |
+								    CF_PAGE_READABLE |
+								    CF_PAGE_WRITABLE |
+								    CF_PAGE_EXEC),
+	[VM_SHARED]					= PAGE_NONE,
+	[VM_SHARED | VM_READ]				= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_READABLE),
+	[VM_SHARED | VM_WRITE]				= PAGE_SHARED,
+	[VM_SHARED | VM_WRITE | VM_READ]		= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_READABLE |
+								   CF_PAGE_SHARED),
+	[VM_SHARED | VM_EXEC]				= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_EXEC),
+	[VM_SHARED | VM_EXEC | VM_READ]			= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_READABLE |
+								   CF_PAGE_EXEC),
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_SHARED |
+								   CF_PAGE_EXEC),
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= __pgprot(CF_PAGE_VALID |
+								   CF_PAGE_ACCESSED |
+								   CF_PAGE_READABLE |
+								   CF_PAGE_SHARED |
+								   CF_PAGE_EXEC)
+};
+DECLARE_VM_GET_PAGE_PROT
diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c
index df7f797c908a..2a375637e007 100644
--- a/arch/m68k/mm/motorola.c
+++ b/arch/m68k/mm/motorola.c
@@ -383,6 +383,35 @@ static void __init map_node(int node)
 }
 
 /*
+ * Alternate definitions that are compile time constants, for
+ * initializing protection_map.  The cachebits are fixed later.
+ */
+#define PAGE_NONE_C	__pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
+#define PAGE_SHARED_C	__pgprot(_PAGE_PRESENT | _PAGE_ACCESSED)
+#define PAGE_COPY_C	__pgprot(_PAGE_PRESENT | _PAGE_RONLY | _PAGE_ACCESSED)
+#define PAGE_READONLY_C	__pgprot(_PAGE_PRESENT | _PAGE_RONLY | _PAGE_ACCESSED)
+
+static pgprot_t protection_map[16] __ro_after_init = {
+	[VM_NONE]					= PAGE_NONE_C,
+	[VM_READ]					= PAGE_READONLY_C,
+	[VM_WRITE]					= PAGE_COPY_C,
+	[VM_WRITE | VM_READ]				= PAGE_COPY_C,
+	[VM_EXEC]					= PAGE_READONLY_C,
+	[VM_EXEC | VM_READ]				= PAGE_READONLY_C,
+	[VM_EXEC | VM_WRITE]				= PAGE_COPY_C,
+	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_COPY_C,
+	[VM_SHARED]					= PAGE_NONE_C,
+	[VM_SHARED | VM_READ]				= PAGE_READONLY_C,
+	[VM_SHARED | VM_WRITE]				= PAGE_SHARED_C,
+	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_SHARED_C,
+	[VM_SHARED | VM_EXEC]				= PAGE_READONLY_C,
+	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_READONLY_C,
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_SHARED_C,
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_SHARED_C
+};
+DECLARE_VM_GET_PAGE_PROT
+
+/*
  * paging_init() continues the virtual memory environment setup which
  * was begun by the code in arch/head.S.
  */
diff --git a/arch/m68k/mm/sun3mmu.c b/arch/m68k/mm/sun3mmu.c
index dad494224497..b619d0d4319c 100644
--- a/arch/m68k/mm/sun3mmu.c
+++ b/arch/m68k/mm/sun3mmu.c
@@ -95,3 +95,23 @@ void __init paging_init(void)
 
 
 }
+
+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_READONLY,
+	[VM_EXEC | VM_READ]				= PAGE_READONLY,
+	[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_SHARED,
+	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_SHARED,
+	[VM_SHARED | VM_EXEC]				= PAGE_READONLY,
+	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_READONLY,
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_SHARED,
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_SHARED
+};
+DECLARE_VM_GET_PAGE_PROT