[PATCH 4/4] MIPS: mm: Clean up setup of protection map

From: Thomas Bogendoerfer
Date: Fri Nov 13 2020 - 06:12:40 EST


Protection map difference between RIXI and non RIXI cpus is _PAGE_NO_EXEC
and _PAGE_NO_READ usage. Both already take care of cpu_has_rixi while
setting up the page bits. So we just need one setup of protection map
and can drop the now unused (and broken for RIXI) PAGE_* defines.

Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
---
arch/mips/include/asm/pgtable.h | 8 ------
arch/mips/mm/cache.c | 55 ++++++++++++++---------------------------
2 files changed, 18 insertions(+), 45 deletions(-)

diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index e5ef0fdd4838..158ba3aa3bf1 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -25,14 +25,6 @@
struct mm_struct;
struct vm_area_struct;

-#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_NO_READ | \
- _page_cachable_default)
-#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
- _page_cachable_default)
-#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_NO_EXEC | \
- _page_cachable_default)
-#define PAGE_READONLY __pgprot(_PAGE_PRESENT | \
- _page_cachable_default)
#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
_PAGE_GLOBAL | _page_cachable_default)
#define PAGE_KERNEL_NC __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index f66a8bfc030e..36bcf4e955e8 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -159,43 +159,24 @@ EXPORT_SYMBOL(_page_cachable_default);

static inline void setup_protection_map(void)
{
- if (cpu_has_rixi) {
- 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);
-
- } else {
- protection_map[0] = PAGE_NONE;
- protection_map[1] = PAGE_READONLY;
- protection_map[2] = PAGE_COPY;
- protection_map[3] = PAGE_COPY;
- protection_map[4] = PAGE_READONLY;
- protection_map[5] = PAGE_READONLY;
- protection_map[6] = PAGE_COPY;
- protection_map[7] = PAGE_COPY;
- protection_map[8] = PAGE_NONE;
- protection_map[9] = PAGE_READONLY;
- protection_map[10] = PAGE_SHARED;
- protection_map[11] = PAGE_SHARED;
- protection_map[12] = PAGE_READONLY;
- protection_map[13] = PAGE_READONLY;
- protection_map[14] = PAGE_SHARED;
- protection_map[15] = PAGE_SHARED;
- }
+ 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
--
2.16.4