powerpc/mm: Merge various PTE bits and accessors definitions

Now that they are almost identical, we can merge some of the definitions
related to the PTE format into common files.

This creates a new pte-common.h which is included by both 32 and 64-bit
right after the CPU specific pte-*.h file, and which defines some
bits to "default" values if they haven't been defined already, and
then provides a generic definition of most of the bit combinations
based on these and exposed to the rest of the kernel.

I also moved to the common pgtable.h most of the "small" accessors to the
PTE bits and modification helpers (pte_mk*). The actual accessors remain
in their separate files.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h
index 7ce331e..ba45c99 100644
--- a/arch/powerpc/include/asm/pgtable-ppc32.h
+++ b/arch/powerpc/include/asm/pgtable-ppc32.h
@@ -97,174 +97,11 @@
 #include <asm/pte-hash32.h>
 #endif
 
-/* If _PAGE_SPECIAL is defined, then we advertise our support for it */
-#ifdef _PAGE_SPECIAL
-#define __HAVE_ARCH_PTE_SPECIAL
-#endif
-
-/*
- * Some bits are only used on some cpu families... Make sure that all
- * the undefined gets defined as 0
- */
-#ifndef _PAGE_HASHPTE
-#define _PAGE_HASHPTE	0
-#endif
-#ifndef _PTE_NONE_MASK
-#define _PTE_NONE_MASK 0
-#endif
-#ifndef _PAGE_SHARED
-#define _PAGE_SHARED	0
-#endif
-#ifndef _PAGE_HWWRITE
-#define _PAGE_HWWRITE	0
-#endif
-#ifndef _PAGE_HWEXEC
-#define _PAGE_HWEXEC	0
-#endif
-#ifndef _PAGE_EXEC
-#define _PAGE_EXEC	0
-#endif
-#ifndef _PAGE_ENDIAN
-#define _PAGE_ENDIAN	0
-#endif
-#ifndef _PAGE_COHERENT
-#define _PAGE_COHERENT	0
-#endif
-#ifndef _PAGE_WRITETHRU
-#define _PAGE_WRITETHRU	0
-#endif
-#ifndef _PAGE_SPECIAL
-#define _PAGE_SPECIAL	0
-#endif
-#ifndef _PMD_PRESENT_MASK
-#define _PMD_PRESENT_MASK	_PMD_PRESENT
-#endif
-#ifndef _PMD_SIZE
-#define _PMD_SIZE	0
-#define PMD_PAGE_SIZE(pmd)	bad_call_to_PMD_PAGE_SIZE()
-#endif
-
-#ifndef _PAGE_KERNEL_RO
-#define _PAGE_KERNEL_RO	0
-#endif
-#ifndef _PAGE_KERNEL_RW
-#define _PAGE_KERNEL_RW	(_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE)
-#endif
-
-#define _PAGE_HPTEFLAGS _PAGE_HASHPTE
-
-/* Location of the PFN in the PTE. Most platforms use the same as _PAGE_SHIFT
- * here (ie, naturally aligned). Platform who don't just pre-define the
- * value so we don't override it here
- */
-#ifndef PTE_RPN_SHIFT
-#define PTE_RPN_SHIFT	(PAGE_SHIFT)
-#endif
-
-#ifdef CONFIG_PTE_64BIT
-#define PTE_RPN_MAX	(1ULL << (64 - PTE_RPN_SHIFT))
-#define PTE_RPN_MASK	(~((1ULL<<PTE_RPN_SHIFT)-1))
-#else
-#define PTE_RPN_MAX	(1UL << (32 - PTE_RPN_SHIFT))
-#define PTE_RPN_MASK	(~((1UL<<PTE_RPN_SHIFT)-1))
-#endif
-
-/* _PAGE_CHG_MASK masks of bits that are to be preserved accross
- * pgprot changes
- */
-#define _PAGE_CHG_MASK	(PTE_RPN_MASK | _PAGE_HPTEFLAGS | _PAGE_DIRTY | \
-                         _PAGE_ACCESSED | _PAGE_SPECIAL)
-
-/* Mask of bits returned by pte_pgprot() */
-#define PAGE_PROT_BITS	(_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \
-			 _PAGE_WRITETHRU | _PAGE_ENDIAN | \
-			 _PAGE_USER | _PAGE_ACCESSED | \
-			 _PAGE_RW | _PAGE_HWWRITE | _PAGE_DIRTY | \
-			 _PAGE_EXEC | _PAGE_HWEXEC)
-
-/*
- * We define 2 sets of base prot bits, one for basic pages (ie,
- * cacheable kernel and user pages) and one for non cacheable
- * pages. We always set _PAGE_COHERENT when SMP is enabled or
- * the processor might need it for DMA coherency.
- */
-#if defined(CONFIG_SMP) || defined(CONFIG_PPC_STD_MMU)
-#define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_COHERENT)
-#else
-#define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED)
-#endif
-#define _PAGE_BASE_NC	(_PAGE_PRESENT | _PAGE_ACCESSED)
-
-/* Permission masks used for kernel mappings */
-#define PAGE_KERNEL	__pgprot(_PAGE_BASE | _PAGE_KERNEL_RW)
-#define PAGE_KERNEL_NC	__pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \
-				 _PAGE_NO_CACHE)
-#define PAGE_KERNEL_NCG	__pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \
-				 _PAGE_NO_CACHE | _PAGE_GUARDED)
-#define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW | _PAGE_EXEC)
-#define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO)
-#define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO | _PAGE_EXEC)
-
-#if defined(CONFIG_KGDB) || defined(CONFIG_XMON) || defined(CONFIG_BDI_SWITCH) ||\
-	defined(CONFIG_KPROBES)
-/* We want the debuggers to be able to set breakpoints anywhere, so
- * don't write protect the kernel text */
-#define PAGE_KERNEL_TEXT	PAGE_KERNEL_X
-#else
-#define PAGE_KERNEL_TEXT	PAGE_KERNEL_ROX
-#endif
-
-#define PAGE_NONE	__pgprot(_PAGE_BASE)
-#define PAGE_READONLY	__pgprot(_PAGE_BASE | _PAGE_USER)
-#define PAGE_READONLY_X	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
-#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)
-
-/*
- * The PowerPC can only do execute protection on a segment (256MB) basis,
- * not on a page basis.  So we consider execute permission the same as read.
- * Also, write permissions imply read permissions.
- * This is the closest we can get..
- */
-#define __P000	PAGE_NONE
-#define __P001	PAGE_READONLY_X
-#define __P010	PAGE_COPY
-#define __P011	PAGE_COPY_X
-#define __P100	PAGE_READONLY
-#define __P101	PAGE_READONLY_X
-#define __P110	PAGE_COPY
-#define __P111	PAGE_COPY_X
-
-#define __S000	PAGE_NONE
-#define __S001	PAGE_READONLY_X
-#define __S010	PAGE_SHARED
-#define __S011	PAGE_SHARED_X
-#define __S100	PAGE_READONLY
-#define __S101	PAGE_READONLY_X
-#define __S110	PAGE_SHARED
-#define __S111	PAGE_SHARED_X
+/* And here we include common definitions */
+#include <asm/pte-common.h>
 
 #ifndef __ASSEMBLY__
-/* Make sure we get a link error if PMD_PAGE_SIZE is ever called on a
- * kernel without large page PMD support */
-extern unsigned long bad_call_to_PMD_PAGE_SIZE(void);
 
-/*
- * Conversions between PTE values and page frame numbers.
- */
-
-#define pte_pfn(x)		(pte_val(x) >> PTE_RPN_SHIFT)
-#define pte_page(x)		pfn_to_page(pte_pfn(x))
-
-#define pfn_pte(pfn, prot)	__pte(((pte_basic_t)(pfn) << PTE_RPN_SHIFT) |\
-					pgprot_val(prot))
-#define mk_pte(page, prot)	pfn_pte(page_to_pfn(page), prot)
-#endif /* __ASSEMBLY__ */
-
-#define pte_none(pte)		((pte_val(pte) & ~_PTE_NONE_MASK) == 0)
-#define pte_present(pte)	(pte_val(pte) & _PAGE_PRESENT)
 #define pte_clear(mm, addr, ptep) \
 	do { pte_update(ptep, ~_PAGE_HASHPTE, 0); } while (0)
 
@@ -273,43 +110,6 @@
 #define	pmd_present(pmd)	(pmd_val(pmd) & _PMD_PRESENT_MASK)
 #define	pmd_clear(pmdp)		do { pmd_val(*(pmdp)) = 0; } while (0)
 
-#ifndef __ASSEMBLY__
-/*
- * The following only work if pte_present() is true.
- * Undefined behaviour if not..
- */
-static inline int pte_write(pte_t pte)		{ return pte_val(pte) & _PAGE_RW; }
-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; }
-static inline int pte_special(pte_t pte)	{ return pte_val(pte) & _PAGE_SPECIAL; }
-
-static inline pte_t pte_wrprotect(pte_t pte) {
-	pte_val(pte) &= ~(_PAGE_RW | _PAGE_HWWRITE); 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_RW; return pte; }
-static inline pte_t pte_mkdirty(pte_t pte) {
-	pte_val(pte) |= _PAGE_DIRTY; return pte; }
-static inline pte_t pte_mkyoung(pte_t pte) {
-	pte_val(pte) |= _PAGE_ACCESSED; return pte; }
-static inline pte_t pte_mkspecial(pte_t pte) {
-	pte_val(pte) |= _PAGE_SPECIAL; return pte; }
-static inline pgprot_t pte_pgprot(pte_t pte)
-{
-	return __pgprot(pte_val(pte) & PAGE_PROT_BITS);
-}
-
-static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
-{
-	pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot);
-	return pte;
-}
-
 /*
  * When flushing the tlb entry for a page, we also need to flush the hash
  * table entry.  flush_hash_pages is assembler (for speed) in hashtable.S.