[PATCH] powerpc: Merge page.h

Merge asm-ppc/page.h and asm-ppc64/page.h into asm-powerpc/page.h,
asm-powerpc/page_32.h and asm-powerpc/page_64.h

Built for PPC (common_defconfig), with ARCH=powerpc, mostly built with
ARCH=ppc (other things break the build). Built and booted on P5 LPAR
for PPC64 with ARCH=ppc/powerpc (pseries_defconfig). Mostly built for
iSeries powerpc.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

include/asm-powerpc/page.h

+#ifndef _ASM_POWERPC_PAGE_H
+#define _ASM_POWERPC_PAGE_H
+
+/*
+ * Copyright (C) 2001,2005 IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifdef __KERNEL__
+#include <linux/config.h>
+#include <asm/asm-compat.h>
+
+/*
+ * On PPC32 page size is 4K. For PPC64 we support either 4K or 64K software
+ * page size. When using 64K pages however, whether we are really supporting
+ * 64K pages in HW or not is irrelevant to those definitions.
+ */
+#ifdef CONFIG_PPC_64K_PAGES
+#define PAGE_SHIFT		16
+#else
+#define PAGE_SHIFT		12
+#endif
+
+#define PAGE_SIZE		(ASM_CONST(1) << PAGE_SHIFT)
+
+/* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */
+#define __HAVE_ARCH_GATE_AREA		1
+
+/*
+ * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we
+ * assign PAGE_MASK to a larger type it gets extended the way we want
+ * (i.e. with 1s in the high bits)
+ */
+#define PAGE_MASK      (~((1 << PAGE_SHIFT) - 1))
+
+#define PAGE_OFFSET     ASM_CONST(CONFIG_KERNEL_START)
+#define KERNELBASE      PAGE_OFFSET
+
+#ifdef CONFIG_DISCONTIGMEM
+#define page_to_pfn(page)	discontigmem_page_to_pfn(page)
+#define pfn_to_page(pfn)	discontigmem_pfn_to_page(pfn)
+#define pfn_valid(pfn)		discontigmem_pfn_valid(pfn)
+#endif
+
+#ifdef CONFIG_FLATMEM
+#define pfn_to_page(pfn)	(mem_map + (pfn))
+#define page_to_pfn(page)	((unsigned long)((page) - mem_map))
+#define pfn_valid(pfn)		((pfn) < max_mapnr)
+#endif
+
+#define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
+#define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
+#define virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
+
+#define __va(x) ((void *)((unsigned long)(x) + KERNELBASE))
+#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET)
+
+/*
+ * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI,
+ * and needs to be executable.  This means the whole heap ends
+ * up being executable.
+ */
+#define VM_DATA_DEFAULT_FLAGS32	(VM_READ | VM_WRITE | VM_EXEC | \
+				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#define VM_DATA_DEFAULT_FLAGS64	(VM_READ | VM_WRITE | \
+				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#ifdef __powerpc64__
+#include <asm/page_64.h>
+#else
+#include <asm/page_32.h>
+#endif
+
+/* align addr on a size boundary - adjust address up/down if needed */
+#define _ALIGN_UP(addr,size)	(((addr)+((size)-1))&(~((size)-1)))
+#define _ALIGN_DOWN(addr,size)	((addr)&(~((size)-1)))
+
+/* align addr on a size boundary - adjust address up if needed */
+#define _ALIGN(addr,size)     _ALIGN_UP(addr,size)
+
+/* to align the pointer to the (next) page boundary */
+#define PAGE_ALIGN(addr)	_ALIGN(addr, PAGE_SIZE)
+
+#ifndef __ASSEMBLY__
+
+#undef STRICT_MM_TYPECHECKS
+
+#ifdef STRICT_MM_TYPECHECKS
+/* These are used to make use of C type-checking. */
+
+/* PTE level */
+typedef struct { pte_basic_t pte; } pte_t;
+#define pte_val(x)	((x).pte)
+#define __pte(x)	((pte_t) { (x) })
+
+/* 64k pages additionally define a bigger "real PTE" type that gathers
+ * the "second half" part of the PTE for pseudo 64k pages
+ */
+#ifdef CONFIG_PPC_64K_PAGES
+typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
+#else
+typedef struct { pte_t pte; } real_pte_t;
+#endif
+
+/* PMD level */
+typedef struct { unsigned long pmd; } pmd_t;
+#define pmd_val(x)	((x).pmd)
+#define __pmd(x)	((pmd_t) { (x) })
+
+/* PUD level exusts only on 4k pages */
+#ifndef CONFIG_PPC_64K_PAGES
+typedef struct { unsigned long pud; } pud_t;
+#define pud_val(x)	((x).pud)
+#define __pud(x)	((pud_t) { (x) })
+#endif
+
+/* PGD level */
+typedef struct { unsigned long pgd; } pgd_t;
+#define pgd_val(x)	((x).pgd)
+#define __pgd(x)	((pgd_t) { (x) })
+
+/* Page protection bits */
+typedef struct { unsigned long pgprot; } pgprot_t;
+#define pgprot_val(x)	((x).pgprot)
+#define __pgprot(x)	((pgprot_t) { (x) })
+
+#else
+
+/*
+ * .. while these make it easier on the compiler
+ */
+
+typedef pte_basic_t pte_t;
+#define pte_val(x)	(x)
+#define __pte(x)	(x)
+
+#ifdef CONFIG_PPC_64K_PAGES
+typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
+#else
+typedef unsigned long real_pte_t;
+#endif
+
+
+typedef unsigned long pmd_t;
+#define pmd_val(x)	(x)
+#define __pmd(x)	(x)
+
+#ifndef CONFIG_PPC_64K_PAGES
+typedef unsigned long pud_t;
+#define pud_val(x)	(x)
+#define __pud(x)	(x)
+#endif
+
+typedef unsigned long pgd_t;
+#define pgd_val(x)	(x)
+#define pgprot_val(x)	(x)
+
+typedef unsigned long pgprot_t;
+#define __pgd(x)	(x)
+#define __pgprot(x)	(x)
+
+#endif
+
+struct page;
+extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg);
+extern void copy_user_page(void *to, void *from, unsigned long vaddr,
+		struct page *p);
+extern int page_is_ram(unsigned long pfn);
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_POWERPC_PAGE_H */

include/asm-powerpc/page_32.h

+#ifndef _ASM_POWERPC_PAGE_32_H
+#define _ASM_POWERPC_PAGE_32_H
+
+#define VM_DATA_DEFAULT_FLAGS	VM_DATA_DEFAULT_FLAGS32
+
+#ifndef __ASSEMBLY__
+/*
+ * The basic type of a PTE - 64 bits for those CPUs with > 32 bit
+ * physical addressing.  For now this just the IBM PPC440.
+ */
+#ifdef CONFIG_PTE_64BIT
+typedef unsigned long long pte_basic_t;
+#define PTE_SHIFT	(PAGE_SHIFT - 3)	/* 512 ptes per page */
+#define PTE_FMT		"%16Lx"
+#else
+typedef unsigned long pte_basic_t;
+#define PTE_SHIFT	(PAGE_SHIFT - 2)	/* 1024 ptes per page */
+#define PTE_FMT		"%.8lx"
+#endif
+
+struct page;
+extern void clear_pages(void *page, int order);
+static inline void clear_page(void *page) { clear_pages(page, 0); }
+extern void copy_page(void *to, void *from);
+
+/* Pure 2^n version of get_order */
+extern __inline__ int get_order(unsigned long size)
+{
+	int lz;
+
+	size = (size-1) >> PAGE_SHIFT;
+	asm ("cntlzw %0,%1" : "=r" (lz) : "r" (size));
+	return 32 - lz;
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_POWERPC_PAGE_32_H */

include/asm-powerpc/page_64.h

+#ifndef _ASM_POWERPC_PAGE_64_H
+#define _ASM_POWERPC_PAGE_64_H
+
+/*
+ * Copyright (C) 2001 PPC64 Team, IBM Corp
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+/*
+ * We always define HW_PAGE_SHIFT to 12 as use of 64K pages remains Linux
+ * specific, every notion of page number shared with the firmware, TCEs,
+ * iommu, etc... still uses a page size of 4K.
+ */
+#define HW_PAGE_SHIFT		12
+#define HW_PAGE_SIZE		(ASM_CONST(1) << HW_PAGE_SHIFT)
+#define HW_PAGE_MASK		(~(HW_PAGE_SIZE-1))
+
+/*
+ * PAGE_FACTOR is the number of bits factor between PAGE_SHIFT and
+ * HW_PAGE_SHIFT, that is 4K pages.
+ */
+#define PAGE_FACTOR		(PAGE_SHIFT - HW_PAGE_SHIFT)
+
+#define REGION_SIZE   4UL
+#define REGION_SHIFT  60UL
+#define REGION_MASK   (((1UL<<REGION_SIZE)-1UL)<<REGION_SHIFT)
+
+#define VMALLOCBASE		ASM_CONST(0xD000000000000000)
+#define VMALLOC_REGION_ID	(VMALLOCBASE >> REGION_SHIFT)
+#define KERNEL_REGION_ID	(KERNELBASE >> REGION_SHIFT)
+#define USER_REGION_ID		(0UL)
+#define REGION_ID(ea)		(((unsigned long)(ea)) >> REGION_SHIFT)
+
+/* Segment size */
+#define SID_SHIFT		28
+#define SID_MASK		0xfffffffffUL
+#define ESID_MASK		0xfffffffff0000000UL
+#define GET_ESID(x)		(((x) >> SID_SHIFT) & SID_MASK)
+
+#ifndef __ASSEMBLY__
+#include <asm/cache.h>
+
+typedef unsigned long pte_basic_t;
+
+static __inline__ void clear_page(void *addr)
+{
+	unsigned long lines, line_size;
+
+	line_size = ppc64_caches.dline_size;
+	lines = ppc64_caches.dlines_per_page;
+
+	__asm__ __volatile__(
+	"mtctr	%1	# clear_page\n\
+1:      dcbz	0,%0\n\
+	add	%0,%0,%3\n\
+	bdnz+	1b"
+        : "=r" (addr)
+        : "r" (lines), "0" (addr), "r" (line_size)
+	: "ctr", "memory");
+}
+
+extern void copy_4K_page(void *to, void *from);
+
+#ifdef CONFIG_PPC_64K_PAGES
+static inline void copy_page(void *to, void *from)
+{
+	unsigned int i;
+	for (i=0; i < (1 << (PAGE_SHIFT - 12)); i++) {
+		copy_4K_page(to, from);
+		to += 4096;
+		from += 4096;
+	}
+}
+#else /* CONFIG_PPC_64K_PAGES */
+static inline void copy_page(void *to, void *from)
+{
+	copy_4K_page(to, from);
+}
+#endif /* CONFIG_PPC_64K_PAGES */
+
+/* Log 2 of page table size */
+extern u64 ppc64_pft_size;
+
+/* Large pages size */
+extern unsigned int HPAGE_SHIFT;
+#define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
+#define HPAGE_MASK		(~(HPAGE_SIZE - 1))
+#define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
+
+#endif /* __ASSEMBLY__ */
+
+#ifdef CONFIG_HUGETLB_PAGE
+
+#define HTLB_AREA_SHIFT		40
+#define HTLB_AREA_SIZE		(1UL << HTLB_AREA_SHIFT)
+#define GET_HTLB_AREA(x)	((x) >> HTLB_AREA_SHIFT)
+
+#define LOW_ESID_MASK(addr, len)    (((1U << (GET_ESID(addr+len-1)+1)) \
+		                      - (1U << GET_ESID(addr))) & 0xffff)
+#define HTLB_AREA_MASK(addr, len)   (((1U << (GET_HTLB_AREA(addr+len-1)+1)) \
+		                      - (1U << GET_HTLB_AREA(addr))) & 0xffff)
+
+#define ARCH_HAS_HUGEPAGE_ONLY_RANGE
+#define ARCH_HAS_PREPARE_HUGEPAGE_RANGE
+#define ARCH_HAS_SETCLEAR_HUGE_PTE
+
+#define touches_hugepage_low_range(mm, addr, len) \
+	(LOW_ESID_MASK((addr), (len)) & (mm)->context.low_htlb_areas)
+#define touches_hugepage_high_range(mm, addr, len) \
+	(HTLB_AREA_MASK((addr), (len)) & (mm)->context.high_htlb_areas)
+
+#define __within_hugepage_low_range(addr, len, segmask) \
+	((LOW_ESID_MASK((addr), (len)) | (segmask)) == (segmask))
+#define within_hugepage_low_range(addr, len) \
+	__within_hugepage_low_range((addr), (len), \
+				    current->mm->context.low_htlb_areas)
+#define __within_hugepage_high_range(addr, len, zonemask) \
+	((HTLB_AREA_MASK((addr), (len)) | (zonemask)) == (zonemask))
+#define within_hugepage_high_range(addr, len) \
+	__within_hugepage_high_range((addr), (len), \
+				    current->mm->context.high_htlb_areas)
+
+#define is_hugepage_only_range(mm, addr, len) \
+	(touches_hugepage_high_range((mm), (addr), (len)) || \
+	  touches_hugepage_low_range((mm), (addr), (len)))
+#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
+
+#define in_hugepage_area(context, addr) \
+	(cpu_has_feature(CPU_FTR_16M_PAGE) && \
+	 ( ((1 << GET_HTLB_AREA(addr)) & (context).high_htlb_areas) || \
+	   ( ((addr) < 0x100000000L) && \
+	     ((1 << GET_ESID(addr)) & (context).low_htlb_areas) ) ) )
+
+#else /* !CONFIG_HUGETLB_PAGE */
+
+#define in_hugepage_area(mm, addr)	0
+
+#endif /* !CONFIG_HUGETLB_PAGE */
+
+#ifdef MODULE
+#define __page_aligned __attribute__((__aligned__(PAGE_SIZE)))
+#else
+#define __page_aligned \
+	__attribute__((__aligned__(PAGE_SIZE), \
+		__section__(".data.page_aligned")))
+#endif
+
+#define VM_DATA_DEFAULT_FLAGS \
+	(test_thread_flag(TIF_32BIT) ? \
+	 VM_DATA_DEFAULT_FLAGS32 : VM_DATA_DEFAULT_FLAGS64)
+
+/*
+ * This is the default if a program doesn't have a PT_GNU_STACK
+ * program header entry. The PPC64 ELF ABI has a non executable stack
+ * stack by default, so in the absense of a PT_GNU_STACK program header
+ * we turn execute permission off.
+ */
+#define VM_STACK_DEFAULT_FLAGS32	(VM_READ | VM_WRITE | VM_EXEC | \
+					 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#define VM_STACK_DEFAULT_FLAGS64	(VM_READ | VM_WRITE | \
+					 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#define VM_STACK_DEFAULT_FLAGS \
+	(test_thread_flag(TIF_32BIT) ? \
+	 VM_STACK_DEFAULT_FLAGS32 : VM_STACK_DEFAULT_FLAGS64)
+
+#include <asm-generic/page.h>
+
+#endif /* _ASM_POWERPC_PAGE_64_H */