From a7b9f671f2d141528491c346e21e8a179cee9d21 Mon Sep 17 00:00:00 2001 From: LEROY Christophe Date: Mon, 19 Jan 2015 17:04:38 +0100 Subject: [PATCH] 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 [scottwood@freescale.com: fix whitespace] Signed-off-by: Scott Wood --- arch/powerpc/include/asm/pgtable-ppc32.h | 8 +++++--- arch/powerpc/include/asm/pgtable.h | 7 +++++-- arch/powerpc/include/asm/pte-common.h | 25 ++++++++++++++++-------- arch/powerpc/mm/pgtable_32.c | 2 +- 4 files changed, 28 insertions(+), 14 deletions(-) diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h index 234e07c47803..62a3e49a9a14 100644 --- a/arch/powerpc/include/asm/pgtable-ppc32.h +++ b/arch/powerpc/include/asm/pgtable-ppc32.h @@ -275,7 +275,7 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, 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 huge_ptep_set_wrprotect(struct mm_struct *mm, 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 diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index a8805fee0df9..7e77f2ca5132 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -30,7 +30,8 @@ struct mm_struct; #include /* Generic accessors to PTE bits */ -static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW; } +static inline int pte_write(pte_t pte) +{ return (pte_val(pte) & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO; } static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; } static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; } static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; } @@ -115,12 +116,14 @@ static inline unsigned long pte_pfn(pte_t pte) { /* Generic modifiers for PTE bits */ static inline pte_t pte_wrprotect(pte_t pte) { - pte_val(pte) &= ~(_PAGE_RW | _PAGE_HWWRITE); return pte; } + pte_val(pte) &= ~(_PAGE_RW | _PAGE_HWWRITE); + pte_val(pte) |= _PAGE_RO; return pte; } static inline pte_t pte_mkclean(pte_t pte) { pte_val(pte) &= ~(_PAGE_DIRTY | _PAGE_HWWRITE); return pte; } static inline pte_t pte_mkold(pte_t pte) { pte_val(pte) &= ~_PAGE_ACCESSED; return pte; } static inline pte_t pte_mkwrite(pte_t pte) { + pte_val(pte) &= ~_PAGE_RO; pte_val(pte) |= _PAGE_RW; return pte; } static inline pte_t pte_mkdirty(pte_t pte) { pte_val(pte) |= _PAGE_DIRTY; return pte; } diff --git a/arch/powerpc/include/asm/pte-common.h b/arch/powerpc/include/asm/pte-common.h index e040c3595129..2aef9b7a0eb2 100644 --- a/arch/powerpc/include/asm/pte-common.h +++ b/arch/powerpc/include/asm/pte-common.h @@ -34,6 +34,12 @@ #ifndef _PAGE_PSIZE #define _PAGE_PSIZE 0 #endif +/* _PAGE_RO and _PAGE_RW shall not be defined at the same time */ +#ifndef _PAGE_RO +#define _PAGE_RO 0 +#else +#define _PAGE_RW 0 +#endif #ifndef _PMD_PRESENT_MASK #define _PMD_PRESENT_MASK _PMD_PRESENT #endif @@ -42,10 +48,10 @@ #define PMD_PAGE_SIZE(pmd) bad_call_to_PMD_PAGE_SIZE() #endif #ifndef _PAGE_KERNEL_RO -#define _PAGE_KERNEL_RO 0 +#define _PAGE_KERNEL_RO (_PAGE_RO) #endif #ifndef _PAGE_KERNEL_ROX -#define _PAGE_KERNEL_ROX (_PAGE_EXEC) +#define _PAGE_KERNEL_ROX (_PAGE_EXEC | _PAGE_RO) #endif #ifndef _PAGE_KERNEL_RW #define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE) @@ -95,7 +101,7 @@ extern unsigned long bad_call_to_PMD_PAGE_SIZE(void); /* Mask of bits returned by pte_pgprot() */ #define PAGE_PROT_BITS (_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \ _PAGE_WRITETHRU | _PAGE_ENDIAN | _PAGE_4K_PFN | \ - _PAGE_USER | _PAGE_ACCESSED | \ + _PAGE_USER | _PAGE_ACCESSED | _PAGE_RO | \ _PAGE_RW | _PAGE_HWWRITE | _PAGE_DIRTY | _PAGE_EXEC) #ifdef CONFIG_NUMA_BALANCING @@ -128,11 +134,14 @@ extern unsigned long bad_call_to_PMD_PAGE_SIZE(void); */ #define PAGE_NONE __pgprot(_PAGE_BASE) #define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW) -#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC) -#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER) -#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) -#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER) -#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) +#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | \ + _PAGE_EXEC) +#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RO) +#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RO | \ + _PAGE_EXEC) +#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RO) +#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RO | \ + _PAGE_EXEC) #define __P000 PAGE_NONE #define __P001 PAGE_READONLY diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index 6eec88685a71..833139620431 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -146,7 +146,7 @@ void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags) { /* writeable implies dirty for kernel addresses */ - if (flags & _PAGE_RW) + if ((flags & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO) flags |= _PAGE_DIRTY | _PAGE_HWWRITE; /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */ -- 2.39.2