powerpc32: adds handling of _PAGE_RO
Some powerpc like the 8xx don't have a RW bit in PTE bits but a RO
(Read Only) bit. This patch implements the handling of a _PAGE_RO flag
to be used in place of _PAGE_RW
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[scottwood@freescale.com: fix whitespace]
Signed-off-by: Scott Wood <scottwood@freescale.com>
diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h
index 234e07c..62a3e49 100644
--- a/arch/powerpc/include/asm/pgtable-ppc32.h
+++ b/arch/powerpc/include/asm/pgtable-ppc32.h
@@ -275,7 +275,7 @@
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
- pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), 0);
+ pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), _PAGE_RO);
}
static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
@@ -286,9 +286,11 @@
static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
{
- unsigned long bits = pte_val(entry) &
+ unsigned long set = pte_val(entry) &
(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
- pte_update(ptep, 0, bits);
+ unsigned long clr = ~pte_val(entry) & _PAGE_RO;
+
+ pte_update(ptep, clr, set);
}
#define __HAVE_ARCH_PTE_SAME