1 files changed, 317 insertions, 0 deletions
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
new file mode 100644
index 000000000..ef48a55e9
--- /dev/null
+++ b/arch/arm/include/asm/pgtable.h
@@ -0,0 +1,317 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ *  arch/arm/include/asm/pgtable.h
+ *
+ *  Copyright (C) 1995-2002 Russell King
+ */
+#ifndef _ASMARM_PGTABLE_H
+#define _ASMARM_PGTABLE_H
+
+#include <linux/const.h>
+#include <asm/proc-fns.h>
+
+#ifndef __ASSEMBLY__
+/*
+ * ZERO_PAGE is a global shared page that is always zero: used
+ * for zero-mapped memory areas etc..
+ */
+extern struct page *empty_zero_page;
+#define ZERO_PAGE(vaddr)	(empty_zero_page)
+#endif
+
+#ifndef CONFIG_MMU
+
+#include <asm-generic/pgtable-nopud.h>
+#include <asm/pgtable-nommu.h>
+
+#else
+
+#include <asm-generic/pgtable-nopud.h>
+#include <asm/memory.h>
+#include <asm/pgtable-hwdef.h>
+
+
+#include <asm/tlbflush.h>
+
+#ifdef CONFIG_ARM_LPAE
+#include <asm/pgtable-3level.h>
+#else
+#include <asm/pgtable-2level.h>
+#endif
+
+/*
+ * Just any arbitrary offset to the start of the vmalloc VM area: the
+ * current 8MB value just means that there will be a 8MB "hole" after the
+ * physical memory until the kernel virtual memory starts.  That means that
+ * any out-of-bounds memory accesses will hopefully be caught.
+ * The vmalloc() routines leaves a hole of 4kB between each vmalloced
+ * area for the same reason. ;)
+ */
+#define VMALLOC_OFFSET		(8*1024*1024)
+#define VMALLOC_START		(((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
+#define VMALLOC_END		0xff800000UL
+
+#define LIBRARY_TEXT_START	0x0c000000
+
+#ifndef __ASSEMBLY__
+extern void __pte_error(const char *file, int line, pte_t);
+extern void __pmd_error(const char *file, int line, pmd_t);
+extern void __pgd_error(const char *file, int line, pgd_t);
+
+#define pte_ERROR(pte)		__pte_error(__FILE__, __LINE__, pte)
+#define pmd_ERROR(pmd)		__pmd_error(__FILE__, __LINE__, pmd)
+#define pgd_ERROR(pgd)		__pgd_error(__FILE__, __LINE__, pgd)
+
+/*
+ * This is the lowest virtual address we can permit any user space
+ * mapping to be mapped at.  This is particularly important for
+ * non-high vector CPUs.
+ */
+#define FIRST_USER_ADDRESS	(PAGE_SIZE * 2)
+
+/*
+ * Use TASK_SIZE as the ceiling argument for free_pgtables() and
+ * free_pgd_range() to avoid freeing the modules pmd when LPAE is enabled (pmd
+ * page shared between user and kernel).
+ */
+#ifdef CONFIG_ARM_LPAE
+#define USER_PGTABLES_CEILING	TASK_SIZE
+#endif
+
+/*
+ * The pgprot_* and protection_map entries will be fixed up in runtime
+ * to include the cachable and bufferable bits based on memory policy,
+ * as well as any architecture dependent bits like global/ASID and SMP
+ * shared mapping bits.
+ */
+#define _L_PTE_DEFAULT	L_PTE_PRESENT | L_PTE_YOUNG
+
+extern pgprot_t		pgprot_user;
+extern pgprot_t		pgprot_kernel;
+
+#define _MOD_PROT(p, b)	__pgprot(pgprot_val(p) | (b))
+
+#define PAGE_NONE		_MOD_PROT(pgprot_user, L_PTE_XN | L_PTE_RDONLY | L_PTE_NONE)
+#define PAGE_SHARED		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_XN)
+#define PAGE_SHARED_EXEC	_MOD_PROT(pgprot_user, L_PTE_USER)
+#define PAGE_COPY		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
+#define PAGE_COPY_EXEC		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
+#define PAGE_READONLY		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
+#define PAGE_READONLY_EXEC	_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
+#define PAGE_KERNEL		_MOD_PROT(pgprot_kernel, L_PTE_XN)
+#define PAGE_KERNEL_EXEC	pgprot_kernel
+
+#define __PAGE_NONE		__pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN | L_PTE_NONE)
+#define __PAGE_SHARED		__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN)
+#define __PAGE_SHARED_EXEC	__pgprot(_L_PTE_DEFAULT | L_PTE_USER)
+#define __PAGE_COPY		__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
+#define __PAGE_COPY_EXEC	__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
+#define __PAGE_READONLY		__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
+#define __PAGE_READONLY_EXEC	__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
+
+#define __pgprot_modify(prot,mask,bits)		\
+	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
+
+#define pgprot_noncached(prot) \
+	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
+
+#define pgprot_writecombine(prot) \
+	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE)
+
+#define pgprot_stronglyordered(prot) \
+	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
+
+#define pgprot_device(prot) \
+	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_DEV_SHARED | L_PTE_SHARED | L_PTE_DIRTY | L_PTE_XN)
+
+#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
+#define pgprot_dmacoherent(prot) \
+	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN)
+#define __HAVE_PHYS_MEM_ACCESS_PROT
+struct file;
+extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+				     unsigned long size, pgprot_t vma_prot);
+#else
+#define pgprot_dmacoherent(prot) \
+	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN)
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+/*
+ * The table below defines the page protection levels that we insert into our
+ * Linux page table version.  These get translated into the best that the
+ * architecture can perform.  Note that on most ARM hardware:
+ *  1) We cannot do execute protection
+ *  2) If we could do execute protection, then read is implied
+ *  3) write implies read permissions
+ */
+
+#ifndef __ASSEMBLY__
+
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+
+#define pud_page(pud)		pmd_page(__pmd(pud_val(pud)))
+#define pud_write(pud)		pmd_write(__pmd(pud_val(pud)))
+
+#define pmd_none(pmd)		(!pmd_val(pmd))
+
+static inline pte_t *pmd_page_vaddr(pmd_t pmd)
+{
+	return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
+}
+
+#define pmd_page(pmd)		pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
+
+#define pte_pfn(pte)		((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
+#define pfn_pte(pfn,prot)	__pte(__pfn_to_phys(pfn) | pgprot_val(prot))
+
+#define pte_page(pte)		pfn_to_page(pte_pfn(pte))
+#define mk_pte(page,prot)	pfn_pte(page_to_pfn(page), prot)
+
+#define pte_clear(mm,addr,ptep)	set_pte_ext(ptep, __pte(0), 0)
+
+#define pte_isset(pte, val)	((u32)(val) == (val) ? pte_val(pte) & (val) \
+						: !!(pte_val(pte) & (val)))
+#define pte_isclear(pte, val)	(!(pte_val(pte) & (val)))
+
+#define pte_none(pte)		(!pte_val(pte))
+#define pte_present(pte)	(pte_isset((pte), L_PTE_PRESENT))
+#define pte_valid(pte)		(pte_isset((pte), L_PTE_VALID))
+#define pte_accessible(mm, pte)	(mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte))
+#define pte_write(pte)		(pte_isclear((pte), L_PTE_RDONLY))
+#define pte_dirty(pte)		(pte_isset((pte), L_PTE_DIRTY))
+#define pte_young(pte)		(pte_isset((pte), L_PTE_YOUNG))
+#define pte_exec(pte)		(pte_isclear((pte), L_PTE_XN))
+
+#define pte_valid_user(pte)	\
+	(pte_valid(pte) && pte_isset((pte), L_PTE_USER) && pte_young(pte))
+
+static inline bool pte_access_permitted(pte_t pte, bool write)
+{
+	pteval_t mask = L_PTE_PRESENT | L_PTE_USER;
+	pteval_t needed = mask;
+
+	if (write)
+		mask |= L_PTE_RDONLY;
+
+	return (pte_val(pte) & mask) == needed;
+}
+#define pte_access_permitted pte_access_permitted
+
+#if __LINUX_ARM_ARCH__ < 6
+static inline void __sync_icache_dcache(pte_t pteval)
+{
+}
+#else
+extern void __sync_icache_dcache(pte_t pteval);
+#endif
+
+void set_pte_at(struct mm_struct *mm, unsigned long addr,
+		      pte_t *ptep, pte_t pteval);
+
+static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
+{
+	pte_val(pte) &= ~pgprot_val(prot);
+	return pte;
+}
+
+static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
+{
+	pte_val(pte) |= pgprot_val(prot);
+	return pte;
+}
+
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+	return set_pte_bit(pte, __pgprot(L_PTE_RDONLY));
+}
+
+static inline pte_t pte_mkwrite(pte_t pte)
+{
+	return clear_pte_bit(pte, __pgprot(L_PTE_RDONLY));
+}
+
+static inline pte_t pte_mkclean(pte_t pte)
+{
+	return clear_pte_bit(pte, __pgprot(L_PTE_DIRTY));
+}
+
+static inline pte_t pte_mkdirty(pte_t pte)
+{
+	return set_pte_bit(pte, __pgprot(L_PTE_DIRTY));
+}
+
+static inline pte_t pte_mkold(pte_t pte)
+{
+	return clear_pte_bit(pte, __pgprot(L_PTE_YOUNG));
+}
+
+static inline pte_t pte_mkyoung(pte_t pte)
+{
+	return set_pte_bit(pte, __pgprot(L_PTE_YOUNG));
+}
+
+static inline pte_t pte_mkexec(pte_t pte)
+{
+	return clear_pte_bit(pte, __pgprot(L_PTE_XN));
+}
+
+static inline pte_t pte_mknexec(pte_t pte)
+{
+	return set_pte_bit(pte, __pgprot(L_PTE_XN));
+}
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+	const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER |
+		L_PTE_NONE | L_PTE_VALID;
+	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
+	return pte;
+}
+
+/*
+ * Encode and decode a swap entry.  Swap entries are stored in the Linux
+ * page tables as follows:
+ *
+ *   3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
+ *   1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
+ *   <--------------- offset ------------------------> < type -> 0 0
+ *
+ * This gives us up to 31 swap files and 128GB per swap file.  Note that
+ * the offset field is always non-zero.
+ */
+#define __SWP_TYPE_SHIFT	2
+#define __SWP_TYPE_BITS		5
+#define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
+#define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
+
+#define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
+#define __swp_offset(x)		((x).val >> __SWP_OFFSET_SHIFT)
+#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
+
+#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(swp)	__pte((swp).val | PTE_TYPE_FAULT)
+
+/*
+ * It is an error for the kernel to have more swap files than we can
+ * encode in the PTEs.  This ensures that we know when MAX_SWAPFILES
+ * is increased beyond what we presently support.
+ */
+#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
+
+/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
+/* FIXME: this is not correct */
+#define kern_addr_valid(addr)	(1)
+
+/*
+ * We provide our own arch_get_unmapped_area to cope with VIPT caches.
+ */
+#define HAVE_ARCH_UNMAPPED_AREA
+#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* CONFIG_MMU */
+
+#endif /* _ASMARM_PGTABLE_H */