From ca26f936f51b8c9219ede32b1a1f76c4924897aa Mon Sep 17 00:00:00 2001
From: Anshuman Khandual <anshuman.khandual@arm.com>
Date: Mon, 11 Jul 2022 12:35:57 +0530
Subject: arm/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/20220711070600.2378316-24-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
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: "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: 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/arm/mm/mmu.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

(limited to 'arch/arm/mm')

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 5e2be37a198e..2722abddd725 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -405,6 +405,26 @@ void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
 	local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
 }
 
+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
+
 /*
  * Adjust the PMD section entries according to the CPU in use.
  */
-- 
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