[PATCH V4 19/26] ia64/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: linux-ia64@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
 arch/ia64/Kconfig               |  1 +
 arch/ia64/include/asm/pgtable.h | 18 ------------------
 arch/ia64/mm/init.c             | 28 +++++++++++++++++++++++++++-
 3 files changed, 28 insertions(+), 19 deletions(-)

diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index cb93769a9f2a..0510a5737711 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -12,6 +12,7 @@ config IA64
 	select ARCH_HAS_DMA_MARK_CLEAN
 	select ARCH_HAS_STRNCPY_FROM_USER
 	select ARCH_HAS_STRNLEN_USER
+	select ARCH_HAS_VM_GET_PAGE_PROT
 	select ARCH_MIGHT_HAVE_PC_PARPORT
 	select ARCH_MIGHT_HAVE_PC_SERIO
 	select ACPI
diff --git a/arch/ia64/include/asm/pgtable.h b/arch/ia64/include/asm/pgtable.h
index 7aa8f2330fb1..6925e28ae61d 100644
--- a/arch/ia64/include/asm/pgtable.h
+++ b/arch/ia64/include/asm/pgtable.h
@@ -161,24 +161,6 @@
  * attempts to write to the page.
  */
 	/* xwr */
-#define __P000	PAGE_NONE
-#define __P001	PAGE_READONLY
-#define __P010	PAGE_READONLY	/* write to priv pg -> copy & make writable */
-#define __P011	PAGE_READONLY	/* ditto */
-#define __P100	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX)
-#define __P101	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
-#define __P110	PAGE_COPY_EXEC
-#define __P111	PAGE_COPY_EXEC
-
-#define __S000	PAGE_NONE
-#define __S001	PAGE_READONLY
-#define __S010	PAGE_SHARED	/* we don't have (and don't need) write-only */
-#define __S011	PAGE_SHARED
-#define __S100	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX)
-#define __S101	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
-#define __S110	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX)
-#define __S111	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX)
-
 #define pgd_ERROR(e)	printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
 #if CONFIG_PGTABLE_LEVELS == 4
 #define pud_ERROR(e)	printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 855d949d81df..9c91df243d62 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -273,7 +273,7 @@ static int __init gate_vma_init(void)
 	gate_vma.vm_start = FIXADDR_USER_START;
 	gate_vma.vm_end = FIXADDR_USER_END;
 	gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
-	gate_vma.vm_page_prot = __P101;
+	gate_vma.vm_page_prot = __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX);
 
 	return 0;
 }
@@ -490,3 +490,29 @@ void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
 	__remove_pages(start_pfn, nr_pages, altmap);
 }
 #endif
+
+static pgprot_t protection_map[16] __ro_after_init = {
+	[VM_NONE]					= PAGE_NONE,
+	[VM_READ]					= PAGE_READONLY,
+	[VM_WRITE]					= PAGE_READONLY,
+	[VM_WRITE | VM_READ]				= PAGE_READONLY,
+	[VM_EXEC]					= __pgprot(__ACCESS_BITS | _PAGE_PL_3 |
+								   _PAGE_AR_X_RX),
+	[VM_EXEC | VM_READ]				= __pgprot(__ACCESS_BITS | _PAGE_PL_3 |
+								   _PAGE_AR_RX),
+	[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]				= __pgprot(__ACCESS_BITS | _PAGE_PL_3 |
+								   _PAGE_AR_X_RX),
+	[VM_SHARED | VM_EXEC | VM_READ]			= __pgprot(__ACCESS_BITS | _PAGE_PL_3 |
+								   _PAGE_AR_RX),
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= __pgprot(__ACCESS_BITS | _PAGE_PL_3 |
+								   _PAGE_AR_RWX),
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= __pgprot(__ACCESS_BITS | _PAGE_PL_3 |
+								   _PAGE_AR_RWX)
+};
+DECLARE_VM_GET_PAGE_PROT
-- 
2.25.1