1 files changed, 492 insertions, 0 deletions
diff --git a/arch/mn10300/include/asm/pgtable.h b/arch/mn10300/include/asm/pgtable.h
new file mode 100644
index 000000000000..6dc30fc827c4
--- /dev/null
+++ b/arch/mn10300/include/asm/pgtable.h
@@ -0,0 +1,492 @@
+/* MN10300 Page table manipulators and constants
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ *
+ *
+ * The Linux memory management assumes a three-level page table setup. On
+ * the i386, we use that, but "fold" the mid level into the top-level page
+ * table, so that we physically have the same two-level page table as the
+ * i386 mmu expects.
+ *
+ * This file contains the functions and defines necessary to modify and use
+ * the i386 page table tree for the purposes of the MN10300 TLB handler
+ * functions.
+ */
+#ifndef _ASM_PGTABLE_H
+#define _ASM_PGTABLE_H
+
+#include <asm/cpu-regs.h>
+
+#ifndef __ASSEMBLY__
+#include <asm/processor.h>
+#include <asm/cache.h>
+#include <linux/threads.h>
+
+#include <asm/bitops.h>
+
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+
+/*
+ * ZERO_PAGE is a global shared page that is always zero: used
+ * for zero-mapped memory areas etc..
+ */
+#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
+extern unsigned long empty_zero_page[1024];
+extern spinlock_t pgd_lock;
+extern struct page *pgd_list;
+
+extern void pmd_ctor(void *, struct kmem_cache *, unsigned long);
+extern void pgtable_cache_init(void);
+extern void paging_init(void);
+
+#endif /* !__ASSEMBLY__ */
+
+/*
+ * The Linux mn10300 paging architecture only implements both the traditional
+ * 2-level page tables
+ */
+#define PGDIR_SHIFT	22
+#define PTRS_PER_PGD	1024
+#define PTRS_PER_PUD	1	/* we don't really have any PUD physically */
+#define PTRS_PER_PMD	1	/* we don't really have any PMD physically */
+#define PTRS_PER_PTE	1024
+
+#define PGD_SIZE	PAGE_SIZE
+#define PMD_SIZE	(1UL << PMD_SHIFT)
+#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
+#define PGDIR_MASK	(~(PGDIR_SIZE - 1))
+
+#define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
+#define FIRST_USER_ADDRESS	0
+
+#define USER_PGD_PTRS		(PAGE_OFFSET >> PGDIR_SHIFT)
+#define KERNEL_PGD_PTRS		(PTRS_PER_PGD - USER_PGD_PTRS)
+
+#define TWOLEVEL_PGDIR_SHIFT	22
+#define BOOT_USER_PGD_PTRS	(__PAGE_OFFSET >> TWOLEVEL_PGDIR_SHIFT)
+#define BOOT_KERNEL_PGD_PTRS	(1024 - BOOT_USER_PGD_PTRS)
+
+#ifndef __ASSEMBLY__
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+#endif
+
+/*
+ * Unfortunately, due to the way the MMU works on the MN10300, the vmalloc VM
+ * area has to be in the lower half of the virtual address range (the upper
+ * half is not translated through the TLB).
+ *
+ * So in this case, the vmalloc area goes at the bottom of the address map
+ * (leaving a hole at the very bottom to catch addressing errors), and
+ * userspace starts immediately above.
+ *
+ * The vmalloc() routines also leaves a hole of 4kB between each vmalloced
+ * area to catch addressing errors.
+ */
+#define VMALLOC_OFFSET	(8 * 1024 * 1024)
+#define VMALLOC_START	(0x70000000)
+#define VMALLOC_END	(0x7C000000)
+
+#ifndef __ASSEMBLY__
+extern pte_t kernel_vmalloc_ptes[(VMALLOC_END - VMALLOC_START) / PAGE_SIZE];
+#endif
+
+/* IPTEL/DPTEL bit assignments */
+#define _PAGE_BIT_VALID		xPTEL_V_BIT
+#define _PAGE_BIT_ACCESSED	xPTEL_UNUSED1_BIT	/* mustn't be loaded into IPTEL/DPTEL */
+#define _PAGE_BIT_NX		xPTEL_UNUSED2_BIT	/* mustn't be loaded into IPTEL/DPTEL */
+#define _PAGE_BIT_CACHE		xPTEL_C_BIT
+#define _PAGE_BIT_PRESENT	xPTEL_PV_BIT
+#define _PAGE_BIT_DIRTY		xPTEL_D_BIT
+#define _PAGE_BIT_GLOBAL	xPTEL_G_BIT
+
+#define _PAGE_VALID		xPTEL_V
+#define _PAGE_ACCESSED		xPTEL_UNUSED1
+#define _PAGE_NX		xPTEL_UNUSED2		/* no-execute bit */
+#define _PAGE_CACHE		xPTEL_C
+#define _PAGE_PRESENT		xPTEL_PV
+#define _PAGE_DIRTY		xPTEL_D
+#define _PAGE_PROT		xPTEL_PR
+#define _PAGE_PROT_RKNU		xPTEL_PR_ROK
+#define _PAGE_PROT_WKNU		xPTEL_PR_RWK
+#define _PAGE_PROT_RKRU		xPTEL_PR_ROK_ROU
+#define _PAGE_PROT_WKRU		xPTEL_PR_RWK_ROU
+#define _PAGE_PROT_WKWU		xPTEL_PR_RWK_RWU
+#define _PAGE_GLOBAL		xPTEL_G
+#define _PAGE_PSE		xPTEL_PS_4Mb		/* 4MB page */
+
+#define _PAGE_FILE		xPTEL_UNUSED1_BIT	/* set:pagecache unset:swap */
+
+#define __PAGE_PROT_UWAUX	0x040
+#define __PAGE_PROT_USER	0x080
+#define __PAGE_PROT_WRITE	0x100
+
+#define _PAGE_PRESENTV		(_PAGE_PRESENT|_PAGE_VALID)
+#define _PAGE_PROTNONE		0x000	/* If not present */
+
+#ifndef __ASSEMBLY__
+
+#define VMALLOC_VMADDR(x) ((unsigned long)(x))
+
+#define _PAGE_TABLE	(_PAGE_PRESENTV | _PAGE_PROT_WKNU | _PAGE_ACCESSED | _PAGE_DIRTY)
+#define _PAGE_CHG_MASK	(PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
+
+#define __PAGE_NONE	(_PAGE_PRESENTV | _PAGE_PROT_RKNU | _PAGE_ACCESSED | _PAGE_CACHE)
+#define __PAGE_SHARED	(_PAGE_PRESENTV | _PAGE_PROT_WKWU | _PAGE_ACCESSED | _PAGE_CACHE)
+#define __PAGE_COPY	(_PAGE_PRESENTV | _PAGE_PROT_RKRU | _PAGE_ACCESSED | _PAGE_CACHE)
+#define __PAGE_READONLY	(_PAGE_PRESENTV | _PAGE_PROT_RKRU | _PAGE_ACCESSED | _PAGE_CACHE)
+
+#define PAGE_NONE		__pgprot(__PAGE_NONE     | _PAGE_NX)
+#define PAGE_SHARED_NOEXEC	__pgprot(__PAGE_SHARED   | _PAGE_NX)
+#define PAGE_COPY_NOEXEC	__pgprot(__PAGE_COPY     | _PAGE_NX)
+#define PAGE_READONLY_NOEXEC	__pgprot(__PAGE_READONLY | _PAGE_NX)
+#define PAGE_SHARED_EXEC	__pgprot(__PAGE_SHARED)
+#define PAGE_COPY_EXEC		__pgprot(__PAGE_COPY)
+#define PAGE_READONLY_EXEC	__pgprot(__PAGE_READONLY)
+#define PAGE_COPY		PAGE_COPY_NOEXEC
+#define PAGE_READONLY		PAGE_READONLY_NOEXEC
+#define PAGE_SHARED		PAGE_SHARED_EXEC
+
+#define __PAGE_KERNEL_BASE (_PAGE_PRESENTV | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_GLOBAL)
+
+#define __PAGE_KERNEL		(__PAGE_KERNEL_BASE | _PAGE_PROT_WKNU | _PAGE_CACHE | _PAGE_NX)
+#define __PAGE_KERNEL_NOCACHE	(__PAGE_KERNEL_BASE | _PAGE_PROT_WKNU | _PAGE_NX)
+#define __PAGE_KERNEL_EXEC	(__PAGE_KERNEL & ~_PAGE_NX)
+#define __PAGE_KERNEL_RO	(__PAGE_KERNEL_BASE | _PAGE_PROT_RKNU | _PAGE_CACHE | _PAGE_NX)
+#define __PAGE_KERNEL_LARGE	(__PAGE_KERNEL | _PAGE_PSE)
+#define __PAGE_KERNEL_LARGE_EXEC (__PAGE_KERNEL_EXEC | _PAGE_PSE)
+
+#define PAGE_KERNEL		__pgprot(__PAGE_KERNEL)
+#define PAGE_KERNEL_RO		__pgprot(__PAGE_KERNEL_RO)
+#define PAGE_KERNEL_EXEC	__pgprot(__PAGE_KERNEL_EXEC)
+#define PAGE_KERNEL_NOCACHE	__pgprot(__PAGE_KERNEL_NOCACHE)
+#define PAGE_KERNEL_LARGE	__pgprot(__PAGE_KERNEL_LARGE)
+#define PAGE_KERNEL_LARGE_EXEC	__pgprot(__PAGE_KERNEL_LARGE_EXEC)
+
+/*
+ * Whilst the MN10300 can do page protection for execute (given separate data
+ * and insn TLBs), we are not supporting it at the moment. Write permission,
+ * however, always implies read permission (but not execute permission).
+ */
+#define __P000	PAGE_NONE
+#define __P001	PAGE_READONLY_NOEXEC
+#define __P010	PAGE_COPY_NOEXEC
+#define __P011	PAGE_COPY_NOEXEC
+#define __P100	PAGE_READONLY_EXEC
+#define __P101	PAGE_READONLY_EXEC
+#define __P110	PAGE_COPY_EXEC
+#define __P111	PAGE_COPY_EXEC
+
+#define __S000	PAGE_NONE
+#define __S001	PAGE_READONLY_NOEXEC
+#define __S010	PAGE_SHARED_NOEXEC
+#define __S011	PAGE_SHARED_NOEXEC
+#define __S100	PAGE_READONLY_EXEC
+#define __S101	PAGE_READONLY_EXEC
+#define __S110	PAGE_SHARED_EXEC
+#define __S111	PAGE_SHARED_EXEC
+
+/*
+ * Define this to warn about kernel memory accesses that are
+ * done without a 'verify_area(VERIFY_WRITE,..)'
+ */
+#undef TEST_VERIFY_AREA
+
+#define pte_present(x)	(pte_val(x) & _PAGE_VALID)
+#define pte_clear(mm, addr, xp)				\
+do {							\
+	set_pte_at((mm), (addr), (xp), __pte(0));	\
+} while (0)
+
+#define pmd_none(x)	(!pmd_val(x))
+#define pmd_present(x)	(!pmd_none(x))
+#define pmd_clear(xp)	do { set_pmd(xp, __pmd(0)); } while (0)
+#define	pmd_bad(x)	0
+
+
+#define pages_to_mb(x) ((x) >> (20 - PAGE_SHIFT))
+
+#ifndef __ASSEMBLY__
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+static inline int pte_user(pte_t pte)	{ return pte_val(pte) & __PAGE_PROT_USER; }
+static inline int pte_read(pte_t pte)	{ return pte_val(pte) & __PAGE_PROT_USER; }
+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_write(pte_t pte)	{ return pte_val(pte) & __PAGE_PROT_WRITE; }
+static inline int pte_special(pte_t pte){ return 0; }
+
+/*
+ * The following only works if pte_present() is not true.
+ */
+static inline int pte_file(pte_t pte)	{ return pte_val(pte) & _PAGE_FILE; }
+
+static inline pte_t pte_rdprotect(pte_t pte)
+{
+	pte_val(pte) &= ~(__PAGE_PROT_USER|__PAGE_PROT_UWAUX); return pte;
+}
+static inline pte_t pte_exprotect(pte_t pte)
+{
+	pte_val(pte) |= _PAGE_NX; return pte;
+}
+
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+	pte_val(pte) &= ~(__PAGE_PROT_WRITE|__PAGE_PROT_UWAUX); return pte;
+}
+
+static inline pte_t pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
+static inline pte_t pte_mkold(pte_t pte)	{ pte_val(pte) &= ~_PAGE_ACCESSED; 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_mkexec(pte_t pte)	{ pte_val(pte) &= ~_PAGE_NX; return pte; }
+
+static inline pte_t pte_mkread(pte_t pte)
+{
+	pte_val(pte) |= __PAGE_PROT_USER;
+	if (pte_write(pte))
+		pte_val(pte) |= __PAGE_PROT_UWAUX;
+	return pte;
+}
+static inline pte_t pte_mkwrite(pte_t pte)
+{
+	pte_val(pte) |= __PAGE_PROT_WRITE;
+	if (pte_val(pte) & __PAGE_PROT_USER)
+		pte_val(pte) |= __PAGE_PROT_UWAUX;
+	return pte;
+}
+
+static inline pte_t pte_mkspecial(pte_t pte)	{ return pte; }
+
+#define pte_ERROR(e) \
+	printk(KERN_ERR "%s:%d: bad pte %08lx.\n", \
+	       __FILE__, __LINE__, pte_val(e))
+#define pgd_ERROR(e) \
+	printk(KERN_ERR "%s:%d: bad pgd %08lx.\n", \
+	       __FILE__, __LINE__, pgd_val(e))
+
+/*
+ * The "pgd_xxx()" functions here are trivial for a folded two-level
+ * setup: the pgd is never bad, and a pmd always exists (as it's folded
+ * into the pgd entry)
+ */
+#define pgd_clear(xp)				do { } while (0)
+
+/*
+ * Certain architectures need to do special things when PTEs
+ * within a page table are directly modified.  Thus, the following
+ * hook is made available.
+ */
+#define set_pte(pteptr, pteval)			(*(pteptr) = pteval)
+#define set_pte_at(mm, addr, ptep, pteval)	set_pte((ptep), (pteval))
+#define set_pte_atomic(pteptr, pteval)		set_pte((pteptr), (pteval))
+
+/*
+ * (pmds are folded into pgds so this doesn't get actually called,
+ * but the define is needed for a generic inline function.)
+ */
+#define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
+
+#define ptep_get_and_clear(mm, addr, ptep) \
+	__pte(xchg(&(ptep)->pte, 0))
+#define pte_same(a, b)		(pte_val(a) == pte_val(b))
+#define pte_page(x)		pfn_to_page(pte_pfn(x))
+#define pte_none(x)		(!pte_val(x))
+#define pte_pfn(x)		((unsigned long) (pte_val(x) >> PAGE_SHIFT))
+#define __pfn_addr(pfn)		((pfn) << PAGE_SHIFT)
+#define pfn_pte(pfn, prot)	__pte(__pfn_addr(pfn) | pgprot_val(prot))
+#define pfn_pmd(pfn, prot)	__pmd(__pfn_addr(pfn) | pgprot_val(prot))
+
+/*
+ * All present user pages are user-executable:
+ */
+static inline int pte_exec(pte_t pte)
+{
+	return pte_user(pte);
+}
+
+/*
+ * All present pages are kernel-executable:
+ */
+static inline int pte_exec_kernel(pte_t pte)
+{
+	return 1;
+}
+
+/*
+ * Bits 0 and 1 are taken, split up the 29 bits of offset
+ * into this range:
+ */
+#define PTE_FILE_MAX_BITS	29
+
+#define pte_to_pgoff(pte)	(pte_val(pte) >> 2)
+#define pgoff_to_pte(off)	__pte((off) << 2 | _PAGE_FILE)
+
+/* Encode and de-code a swap entry */
+#define __swp_type(x)			(((x).val >> 2) & 0x3f)
+#define __swp_offset(x)			((x).val >> 8)
+#define __swp_entry(type, offset) \
+	((swp_entry_t) { ((type) << 2) | ((offset) << 8) })
+#define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(x)		__pte((x).val)
+
+static inline
+int ptep_test_and_clear_dirty(struct vm_area_struct *vma, unsigned long addr,
+			      pte_t *ptep)
+{
+	if (!pte_dirty(*ptep))
+		return 0;
+	return test_and_clear_bit(_PAGE_BIT_DIRTY, &ptep->pte);
+}
+
+static inline
+int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr,
+			      pte_t *ptep)
+{
+	if (!pte_young(*ptep))
+		return 0;
+	return test_and_clear_bit(_PAGE_BIT_ACCESSED, &ptep->pte);
+}
+
+static inline
+void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
+{
+	pte_val(*ptep) &= ~(__PAGE_PROT_WRITE|__PAGE_PROT_UWAUX);
+}
+
+static inline void ptep_mkdirty(pte_t *ptep)
+{
+	set_bit(_PAGE_BIT_DIRTY, &ptep->pte);
+}
+
+/*
+ * Macro to mark a page protection value as "uncacheable".  On processors which
+ * do not support it, this is a no-op.
+ */
+#define pgprot_noncached(prot)	__pgprot(pgprot_val(prot) | _PAGE_CACHE)
+
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+
+#define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
+#define mk_pte_huge(entry) \
+	((entry).pte |= _PAGE_PRESENT | _PAGE_PSE | _PAGE_VALID)
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+	pte_val(pte) &= _PAGE_CHG_MASK;
+	pte_val(pte) |= pgprot_val(newprot);
+	return pte;
+}
+
+#define page_pte(page)	page_pte_prot((page), __pgprot(0))
+
+#define pmd_page_kernel(pmd) \
+	((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
+
+#define pmd_page(pmd)	pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)
+
+#define pmd_large(pmd) \
+	((pmd_val(pmd) & (_PAGE_PSE | _PAGE_PRESENT)) == \
+	 (_PAGE_PSE | _PAGE_PRESENT))
+
+/*
+ * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
+ *
+ * this macro returns the index of the entry in the pgd page which would
+ * control the given virtual address
+ */
+#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
+
+/*
+ * pgd_offset() returns a (pgd_t *)
+ * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
+ */
+#define pgd_offset(mm, address)	((mm)->pgd + pgd_index(address))
+
+/*
+ * a shortcut which implies the use of the kernel's pgd, instead
+ * of a process's
+ */
+#define pgd_offset_k(address)	pgd_offset(&init_mm, address)
+
+/*
+ * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
+ *
+ * this macro returns the index of the entry in the pmd page which would
+ * control the given virtual address
+ */
+#define pmd_index(address) \
+	(((address) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
+
+/*
+ * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
+ *
+ * this macro returns the index of the entry in the pte page which would
+ * control the given virtual address
+ */
+#define pte_index(address) \
+	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
+
+#define pte_offset_kernel(dir, address) \
+	((pte_t *) pmd_page_kernel(*(dir)) +  pte_index(address))
+
+/*
+ * Make a given kernel text page executable/non-executable.
+ * Returns the previous executability setting of that page (which
+ * is used to restore the previous state). Used by the SMP bootup code.
+ * NOTE: this is an __init function for security reasons.
+ */
+static inline int set_kernel_exec(unsigned long vaddr, int enable)
+{
+	return 0;
+}
+
+#define pte_offset_map(dir, address) \
+	((pte_t *) page_address(pmd_page(*(dir))) + pte_index(address))
+#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
+#define pte_unmap(pte)		do {} while (0)
+#define pte_unmap_nested(pte)	do {} while (0)
+
+/*
+ * The MN10300 has external MMU info in the form of a TLB: this is adapted from
+ * the kernel page tables containing the necessary information by tlb-mn10300.S
+ */
+extern void update_mmu_cache(struct vm_area_struct *vma,
+			     unsigned long address, pte_t pte);
+
+#endif /* !__ASSEMBLY__ */
+
+#define kern_addr_valid(addr)	(1)
+
+#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
+	remap_pfn_range((vma), (vaddr), (pfn), (size), (prot))
+
+#define MK_IOSPACE_PFN(space, pfn)	(pfn)
+#define GET_IOSPACE(pfn)		0
+#define GET_PFN(pfn)			(pfn)
+
+#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
+#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
+#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
+#define __HAVE_ARCH_PTEP_SET_WRPROTECT
+#define __HAVE_ARCH_PTEP_MKDIRTY
+#define __HAVE_ARCH_PTE_SAME
+#include <asm-generic/pgtable.h>
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_PGTABLE_H */