[PATCH V3 07/30] mips/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT

Anshuman Khandual
2022-02-28T10:51:28Z

This defines and exports a platform specific custom vm_get_page_prot() via
subscribing ARCH_HAS_VM_GET_PAGE_PROT. Subsequently all __SXXX and __PXXX
macros can be dropped which are no longer needed.

Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
arch/mips/Kconfig | 1 +
arch/mips/include/asm/pgtable.h | 22 ------------
arch/mips/mm/cache.c | 60 +++++++++++++++++++--------------
3 files changed, 36 insertions(+), 47 deletions(-)

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 058446f01487..fcbfc52a1567 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -13,6 +13,7 @@ config MIPS
select ARCH_HAS_STRNLEN_USER
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_HAS_VM_GET_PAGE_PROT
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_KEEP_MEMBLOCK
select ARCH_SUPPORTS_UPROBES
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 7b8037f25d9e..bf193ad4f195 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -41,28 +41,6 @@ struct vm_area_struct;
* by reasonable means..
*/

-/*
- * Dummy values to fill the table in mmap.c
- * The real values will be generated at runtime
- */
-#define __P000 __pgprot(0)
-#define __P001 __pgprot(0)
-#define __P010 __pgprot(0)
-#define __P011 __pgprot(0)
-#define __P100 __pgprot(0)
-#define __P101 __pgprot(0)
-#define __P110 __pgprot(0)
-#define __P111 __pgprot(0)
-
-#define __S000 __pgprot(0)
-#define __S001 __pgprot(0)
-#define __S010 __pgprot(0)
-#define __S011 __pgprot(0)
-#define __S100 __pgprot(0)
-#define __S101 __pgprot(0)
-#define __S110 __pgprot(0)
-#define __S111 __pgprot(0)
-
extern unsigned long _page_cachable_default;
extern void __update_cache(unsigned long address, pte_t pte);

diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index 830ab91e574f..9f33ce4fb105 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -159,30 +159,6 @@ EXPORT_SYMBOL(_page_cachable_default);

#define PM(p) __pgprot(_page_cachable_default | (p))

-static inline void setup_protection_map(void)
-{
- protection_map[0] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
- protection_map[1] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
- protection_map[2] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
- protection_map[3] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
- protection_map[4] = PM(_PAGE_PRESENT);
- protection_map[5] = PM(_PAGE_PRESENT);
- protection_map[6] = PM(_PAGE_PRESENT);
- protection_map[7] = PM(_PAGE_PRESENT);
-
- protection_map[8] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
- protection_map[9] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
- protection_map[10] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE |
- _PAGE_NO_READ);
- protection_map[11] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
- protection_map[12] = PM(_PAGE_PRESENT);
- protection_map[13] = PM(_PAGE_PRESENT);
- protection_map[14] = PM(_PAGE_PRESENT | _PAGE_WRITE);
- protection_map[15] = PM(_PAGE_PRESENT | _PAGE_WRITE);
-}
-
-#undef PM
-
void cpu_cache_init(void)
{
if (cpu_has_3k_cache) {
@@ -206,6 +182,40 @@ void cpu_cache_init(void)

octeon_cache_init();
}
+}

- setup_protection_map();
+pgprot_t vm_get_page_prot(unsigned long vm_flags)
+{
+ switch (vm_flags & (VM_READ | VM_WRITE | VM_EXEC | VM_SHARED)) {
+ case VM_NONE:
+ return PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
+ case VM_READ:
+ return PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
+ case VM_WRITE:
+ return PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
+ case VM_WRITE | VM_READ:
+ return PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
+ case VM_EXEC:
+ case VM_EXEC | VM_READ:
+ case VM_EXEC | VM_WRITE:
+ case VM_EXEC | VM_WRITE | VM_READ:
+ return PM(_PAGE_PRESENT);
+ case VM_SHARED:
+ return PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
+ case VM_SHARED | VM_READ:
+ return PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
+ case VM_SHARED | VM_WRITE:
+ return PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
+ case VM_SHARED | VM_WRITE | VM_READ:
+ return PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
+ case VM_SHARED | VM_EXEC:
+ case VM_SHARED | VM_EXEC | VM_READ:
+ return PM(_PAGE_PRESENT);
+ case VM_SHARED | VM_EXEC | VM_WRITE:
+ case VM_SHARED | VM_EXEC | VM_WRITE | VM_READ:
+ return PM(_PAGE_PRESENT | _PAGE_WRITE);
+ default:
+ BUILD_BUG();
+ }
}
+EXPORT_SYMBOL(vm_get_page_prot);
--
2.25.1