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-rw-r--r--arch/riscv/include/asm/pgtable.h931
1 files changed, 931 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
new file mode 100644
index 000000000..511cb385b
--- /dev/null
+++ b/arch/riscv/include/asm/pgtable.h
@@ -0,0 +1,931 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ */
+
+#ifndef _ASM_RISCV_PGTABLE_H
+#define _ASM_RISCV_PGTABLE_H
+
+#include <linux/mmzone.h>
+#include <linux/sizes.h>
+
+#include <asm/pgtable-bits.h>
+
+#ifndef CONFIG_MMU
+#define KERNEL_LINK_ADDR PAGE_OFFSET
+#define KERN_VIRT_SIZE (UL(-1))
+#else
+
+#define ADDRESS_SPACE_END (UL(-1))
+
+#ifdef CONFIG_64BIT
+/* Leave 2GB for kernel and BPF at the end of the address space */
+#define KERNEL_LINK_ADDR (ADDRESS_SPACE_END - SZ_2G + 1)
+#else
+#define KERNEL_LINK_ADDR PAGE_OFFSET
+#endif
+
+/* Number of entries in the page global directory */
+#define PTRS_PER_PGD (PAGE_SIZE / sizeof(pgd_t))
+/* Number of entries in the page table */
+#define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t))
+
+/*
+ * Half of the kernel address space (1/4 of the entries of the page global
+ * directory) is for the direct mapping.
+ */
+#define KERN_VIRT_SIZE ((PTRS_PER_PGD / 2 * PGDIR_SIZE) / 2)
+
+#define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1)
+#define VMALLOC_END PAGE_OFFSET
+#define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE)
+
+#define BPF_JIT_REGION_SIZE (SZ_128M)
+#ifdef CONFIG_64BIT
+#define BPF_JIT_REGION_START (BPF_JIT_REGION_END - BPF_JIT_REGION_SIZE)
+#define BPF_JIT_REGION_END (MODULES_END)
+#else
+#define BPF_JIT_REGION_START (PAGE_OFFSET - BPF_JIT_REGION_SIZE)
+#define BPF_JIT_REGION_END (VMALLOC_END)
+#endif
+
+/* Modules always live before the kernel */
+#ifdef CONFIG_64BIT
+/* This is used to define the end of the KASAN shadow region */
+#define MODULES_LOWEST_VADDR (KERNEL_LINK_ADDR - SZ_2G)
+#define MODULES_VADDR (PFN_ALIGN((unsigned long)&_end) - SZ_2G)
+#define MODULES_END (PFN_ALIGN((unsigned long)&_start))
+#endif
+
+/*
+ * Roughly size the vmemmap space to be large enough to fit enough
+ * struct pages to map half the virtual address space. Then
+ * position vmemmap directly below the VMALLOC region.
+ */
+#define VA_BITS_SV32 32
+#ifdef CONFIG_64BIT
+#define VA_BITS_SV39 39
+#define VA_BITS_SV48 48
+#define VA_BITS_SV57 57
+
+#define VA_BITS (pgtable_l5_enabled ? \
+ VA_BITS_SV57 : (pgtable_l4_enabled ? VA_BITS_SV48 : VA_BITS_SV39))
+#else
+#define VA_BITS VA_BITS_SV32
+#endif
+
+#define VMEMMAP_SHIFT \
+ (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT)
+#define VMEMMAP_SIZE BIT(VMEMMAP_SHIFT)
+#define VMEMMAP_END VMALLOC_START
+#define VMEMMAP_START (VMALLOC_START - VMEMMAP_SIZE)
+
+/*
+ * Define vmemmap for pfn_to_page & page_to_pfn calls. Needed if kernel
+ * is configured with CONFIG_SPARSEMEM_VMEMMAP enabled.
+ */
+#define vmemmap ((struct page *)VMEMMAP_START)
+
+#define PCI_IO_SIZE SZ_16M
+#define PCI_IO_END VMEMMAP_START
+#define PCI_IO_START (PCI_IO_END - PCI_IO_SIZE)
+
+#define FIXADDR_TOP PCI_IO_START
+#ifdef CONFIG_64BIT
+#define MAX_FDT_SIZE PMD_SIZE
+#define FIX_FDT_SIZE (MAX_FDT_SIZE + SZ_2M)
+#define FIXADDR_SIZE (PMD_SIZE + FIX_FDT_SIZE)
+#else
+#define MAX_FDT_SIZE PGDIR_SIZE
+#define FIX_FDT_SIZE MAX_FDT_SIZE
+#define FIXADDR_SIZE (PGDIR_SIZE + FIX_FDT_SIZE)
+#endif
+#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
+
+#endif
+
+#ifdef CONFIG_XIP_KERNEL
+#define XIP_OFFSET SZ_32M
+#define XIP_OFFSET_MASK (SZ_32M - 1)
+#else
+#define XIP_OFFSET 0
+#endif
+
+#ifndef __ASSEMBLY__
+
+#include <asm/page.h>
+#include <asm/tlbflush.h>
+#include <linux/mm_types.h>
+#include <asm/compat.h>
+
+#define __page_val_to_pfn(_val) (((_val) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT)
+
+#ifdef CONFIG_64BIT
+#include <asm/pgtable-64.h>
+
+#define VA_USER_SV39 (UL(1) << (VA_BITS_SV39 - 1))
+#define VA_USER_SV48 (UL(1) << (VA_BITS_SV48 - 1))
+#define VA_USER_SV57 (UL(1) << (VA_BITS_SV57 - 1))
+
+#ifdef CONFIG_COMPAT
+#define MMAP_VA_BITS_64 ((VA_BITS >= VA_BITS_SV48) ? VA_BITS_SV48 : VA_BITS)
+#define MMAP_MIN_VA_BITS_64 (VA_BITS_SV39)
+#define MMAP_VA_BITS (is_compat_task() ? VA_BITS_SV32 : MMAP_VA_BITS_64)
+#define MMAP_MIN_VA_BITS (is_compat_task() ? VA_BITS_SV32 : MMAP_MIN_VA_BITS_64)
+#else
+#define MMAP_VA_BITS ((VA_BITS >= VA_BITS_SV48) ? VA_BITS_SV48 : VA_BITS)
+#define MMAP_MIN_VA_BITS (VA_BITS_SV39)
+#endif /* CONFIG_COMPAT */
+
+#else
+#include <asm/pgtable-32.h>
+#endif /* CONFIG_64BIT */
+
+#include <linux/page_table_check.h>
+
+#ifdef CONFIG_XIP_KERNEL
+#define XIP_FIXUP(addr) ({ \
+ uintptr_t __a = (uintptr_t)(addr); \
+ (__a >= CONFIG_XIP_PHYS_ADDR && \
+ __a < CONFIG_XIP_PHYS_ADDR + XIP_OFFSET * 2) ? \
+ __a - CONFIG_XIP_PHYS_ADDR + CONFIG_PHYS_RAM_BASE - XIP_OFFSET :\
+ __a; \
+ })
+#else
+#define XIP_FIXUP(addr) (addr)
+#endif /* CONFIG_XIP_KERNEL */
+
+struct pt_alloc_ops {
+ pte_t *(*get_pte_virt)(phys_addr_t pa);
+ phys_addr_t (*alloc_pte)(uintptr_t va);
+#ifndef __PAGETABLE_PMD_FOLDED
+ pmd_t *(*get_pmd_virt)(phys_addr_t pa);
+ phys_addr_t (*alloc_pmd)(uintptr_t va);
+ pud_t *(*get_pud_virt)(phys_addr_t pa);
+ phys_addr_t (*alloc_pud)(uintptr_t va);
+ p4d_t *(*get_p4d_virt)(phys_addr_t pa);
+ phys_addr_t (*alloc_p4d)(uintptr_t va);
+#endif
+};
+
+extern struct pt_alloc_ops pt_ops __initdata;
+
+#ifdef CONFIG_MMU
+/* Number of PGD entries that a user-mode program can use */
+#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
+
+/* Page protection bits */
+#define _PAGE_BASE (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_USER)
+
+#define PAGE_NONE __pgprot(_PAGE_PROT_NONE | _PAGE_READ)
+#define PAGE_READ __pgprot(_PAGE_BASE | _PAGE_READ)
+#define PAGE_WRITE __pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_WRITE)
+#define PAGE_EXEC __pgprot(_PAGE_BASE | _PAGE_EXEC)
+#define PAGE_READ_EXEC __pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_EXEC)
+#define PAGE_WRITE_EXEC __pgprot(_PAGE_BASE | _PAGE_READ | \
+ _PAGE_EXEC | _PAGE_WRITE)
+
+#define PAGE_COPY PAGE_READ
+#define PAGE_COPY_EXEC PAGE_READ_EXEC
+#define PAGE_SHARED PAGE_WRITE
+#define PAGE_SHARED_EXEC PAGE_WRITE_EXEC
+
+#define _PAGE_KERNEL (_PAGE_READ \
+ | _PAGE_WRITE \
+ | _PAGE_PRESENT \
+ | _PAGE_ACCESSED \
+ | _PAGE_DIRTY \
+ | _PAGE_GLOBAL)
+
+#define PAGE_KERNEL __pgprot(_PAGE_KERNEL)
+#define PAGE_KERNEL_READ __pgprot(_PAGE_KERNEL & ~_PAGE_WRITE)
+#define PAGE_KERNEL_EXEC __pgprot(_PAGE_KERNEL | _PAGE_EXEC)
+#define PAGE_KERNEL_READ_EXEC __pgprot((_PAGE_KERNEL & ~_PAGE_WRITE) \
+ | _PAGE_EXEC)
+
+#define PAGE_TABLE __pgprot(_PAGE_TABLE)
+
+#define _PAGE_IOREMAP ((_PAGE_KERNEL & ~_PAGE_MTMASK) | _PAGE_IO)
+#define PAGE_KERNEL_IO __pgprot(_PAGE_IOREMAP)
+
+extern pgd_t swapper_pg_dir[];
+extern pgd_t trampoline_pg_dir[];
+extern pgd_t early_pg_dir[];
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline int pmd_present(pmd_t pmd)
+{
+ /*
+ * Checking for _PAGE_LEAF is needed too because:
+ * When splitting a THP, split_huge_page() will temporarily clear
+ * the present bit, in this situation, pmd_present() and
+ * pmd_trans_huge() still needs to return true.
+ */
+ return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE | _PAGE_LEAF));
+}
+#else
+static inline int pmd_present(pmd_t pmd)
+{
+ return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
+}
+#endif
+
+static inline int pmd_none(pmd_t pmd)
+{
+ return (pmd_val(pmd) == 0);
+}
+
+static inline int pmd_bad(pmd_t pmd)
+{
+ return !pmd_present(pmd) || (pmd_val(pmd) & _PAGE_LEAF);
+}
+
+#define pmd_leaf pmd_leaf
+static inline int pmd_leaf(pmd_t pmd)
+{
+ return pmd_present(pmd) && (pmd_val(pmd) & _PAGE_LEAF);
+}
+
+static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
+{
+ *pmdp = pmd;
+}
+
+static inline void pmd_clear(pmd_t *pmdp)
+{
+ set_pmd(pmdp, __pmd(0));
+}
+
+static inline pgd_t pfn_pgd(unsigned long pfn, pgprot_t prot)
+{
+ unsigned long prot_val = pgprot_val(prot);
+
+ ALT_THEAD_PMA(prot_val);
+
+ return __pgd((pfn << _PAGE_PFN_SHIFT) | prot_val);
+}
+
+static inline unsigned long _pgd_pfn(pgd_t pgd)
+{
+ return __page_val_to_pfn(pgd_val(pgd));
+}
+
+static inline struct page *pmd_page(pmd_t pmd)
+{
+ return pfn_to_page(__page_val_to_pfn(pmd_val(pmd)));
+}
+
+static inline unsigned long pmd_page_vaddr(pmd_t pmd)
+{
+ return (unsigned long)pfn_to_virt(__page_val_to_pfn(pmd_val(pmd)));
+}
+
+static inline pte_t pmd_pte(pmd_t pmd)
+{
+ return __pte(pmd_val(pmd));
+}
+
+static inline pte_t pud_pte(pud_t pud)
+{
+ return __pte(pud_val(pud));
+}
+
+#ifdef CONFIG_RISCV_ISA_SVNAPOT
+
+static __always_inline bool has_svnapot(void)
+{
+ return riscv_has_extension_likely(RISCV_ISA_EXT_SVNAPOT);
+}
+
+static inline unsigned long pte_napot(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_NAPOT;
+}
+
+static inline pte_t pte_mknapot(pte_t pte, unsigned int order)
+{
+ int pos = order - 1 + _PAGE_PFN_SHIFT;
+ unsigned long napot_bit = BIT(pos);
+ unsigned long napot_mask = ~GENMASK(pos, _PAGE_PFN_SHIFT);
+
+ return __pte((pte_val(pte) & napot_mask) | napot_bit | _PAGE_NAPOT);
+}
+
+#else
+
+static __always_inline bool has_svnapot(void) { return false; }
+
+static inline unsigned long pte_napot(pte_t pte)
+{
+ return 0;
+}
+
+#endif /* CONFIG_RISCV_ISA_SVNAPOT */
+
+/* Yields the page frame number (PFN) of a page table entry */
+static inline unsigned long pte_pfn(pte_t pte)
+{
+ unsigned long res = __page_val_to_pfn(pte_val(pte));
+
+ if (has_svnapot() && pte_napot(pte))
+ res = res & (res - 1UL);
+
+ return res;
+}
+
+#define pte_page(x) pfn_to_page(pte_pfn(x))
+
+/* Constructs a page table entry */
+static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot)
+{
+ unsigned long prot_val = pgprot_val(prot);
+
+ ALT_THEAD_PMA(prot_val);
+
+ return __pte((pfn << _PAGE_PFN_SHIFT) | prot_val);
+}
+
+#define mk_pte(page, prot) pfn_pte(page_to_pfn(page), prot)
+
+static inline int pte_present(pte_t pte)
+{
+ return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
+}
+
+static inline int pte_none(pte_t pte)
+{
+ return (pte_val(pte) == 0);
+}
+
+static inline int pte_write(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_WRITE;
+}
+
+static inline int pte_exec(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_EXEC;
+}
+
+static inline int pte_user(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_USER;
+}
+
+static inline int pte_huge(pte_t pte)
+{
+ return pte_present(pte) && (pte_val(pte) & _PAGE_LEAF);
+}
+
+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_special(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_SPECIAL;
+}
+
+/* static inline pte_t pte_rdprotect(pte_t pte) */
+
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~(_PAGE_WRITE));
+}
+
+/* static inline pte_t pte_mkread(pte_t pte) */
+
+static inline pte_t pte_mkwrite_novma(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_WRITE);
+}
+
+/* static inline pte_t pte_mkexec(pte_t pte) */
+
+static inline pte_t pte_mkdirty(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_DIRTY);
+}
+
+static inline pte_t pte_mkclean(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~(_PAGE_DIRTY));
+}
+
+static inline pte_t pte_mkyoung(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_ACCESSED);
+}
+
+static inline pte_t pte_mkold(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~(_PAGE_ACCESSED));
+}
+
+static inline pte_t pte_mkspecial(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_SPECIAL);
+}
+
+static inline pte_t pte_mkhuge(pte_t pte)
+{
+ return pte;
+}
+
+#ifdef CONFIG_NUMA_BALANCING
+/*
+ * See the comment in include/asm-generic/pgtable.h
+ */
+static inline int pte_protnone(pte_t pte)
+{
+ return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE)) == _PAGE_PROT_NONE;
+}
+
+static inline int pmd_protnone(pmd_t pmd)
+{
+ return pte_protnone(pmd_pte(pmd));
+}
+#endif
+
+/* Modify page protection bits */
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+ unsigned long newprot_val = pgprot_val(newprot);
+
+ ALT_THEAD_PMA(newprot_val);
+
+ return __pte((pte_val(pte) & _PAGE_CHG_MASK) | newprot_val);
+}
+
+#define pgd_ERROR(e) \
+ pr_err("%s:%d: bad pgd " PTE_FMT ".\n", __FILE__, __LINE__, pgd_val(e))
+
+
+/* Commit new configuration to MMU hardware */
+static inline void update_mmu_cache_range(struct vm_fault *vmf,
+ struct vm_area_struct *vma, unsigned long address,
+ pte_t *ptep, unsigned int nr)
+{
+ /*
+ * The kernel assumes that TLBs don't cache invalid entries, but
+ * in RISC-V, SFENCE.VMA specifies an ordering constraint, not a
+ * cache flush; it is necessary even after writing invalid entries.
+ * Relying on flush_tlb_fix_spurious_fault would suffice, but
+ * the extra traps reduce performance. So, eagerly SFENCE.VMA.
+ */
+ while (nr--)
+ local_flush_tlb_page(address + nr * PAGE_SIZE);
+}
+#define update_mmu_cache(vma, addr, ptep) \
+ update_mmu_cache_range(NULL, vma, addr, ptep, 1)
+
+#define __HAVE_ARCH_UPDATE_MMU_TLB
+#define update_mmu_tlb update_mmu_cache
+
+static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp)
+{
+ pte_t *ptep = (pte_t *)pmdp;
+
+ update_mmu_cache(vma, address, ptep);
+}
+
+#define __HAVE_ARCH_PTE_SAME
+static inline int pte_same(pte_t pte_a, pte_t pte_b)
+{
+ return pte_val(pte_a) == pte_val(pte_b);
+}
+
+/*
+ * Certain architectures need to do special things when PTEs within
+ * a page table are directly modified. Thus, the following hook is
+ * made available.
+ */
+static inline void set_pte(pte_t *ptep, pte_t pteval)
+{
+ *ptep = pteval;
+}
+
+void flush_icache_pte(pte_t pte);
+
+static inline void __set_pte_at(pte_t *ptep, pte_t pteval)
+{
+ if (pte_present(pteval) && pte_exec(pteval))
+ flush_icache_pte(pteval);
+
+ set_pte(ptep, pteval);
+}
+
+static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pteval, unsigned int nr)
+{
+ page_table_check_ptes_set(mm, ptep, pteval, nr);
+
+ for (;;) {
+ __set_pte_at(ptep, pteval);
+ if (--nr == 0)
+ break;
+ ptep++;
+ pte_val(pteval) += 1 << _PAGE_PFN_SHIFT;
+ }
+}
+#define set_ptes set_ptes
+
+static inline void pte_clear(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ __set_pte_at(ptep, __pte(0));
+}
+
+#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
+static inline int ptep_set_access_flags(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep,
+ pte_t entry, int dirty)
+{
+ if (!pte_same(*ptep, entry))
+ __set_pte_at(ptep, entry);
+ /*
+ * update_mmu_cache will unconditionally execute, handling both
+ * the case that the PTE changed and the spurious fault case.
+ */
+ return true;
+}
+
+#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
+static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
+ unsigned long address, pte_t *ptep)
+{
+ pte_t pte = __pte(atomic_long_xchg((atomic_long_t *)ptep, 0));
+
+ page_table_check_pte_clear(mm, pte);
+
+ return pte;
+}
+
+#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
+static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
+ unsigned long address,
+ pte_t *ptep)
+{
+ if (!pte_young(*ptep))
+ return 0;
+ return test_and_clear_bit(_PAGE_ACCESSED_OFFSET, &pte_val(*ptep));
+}
+
+#define __HAVE_ARCH_PTEP_SET_WRPROTECT
+static inline void ptep_set_wrprotect(struct mm_struct *mm,
+ unsigned long address, pte_t *ptep)
+{
+ atomic_long_and(~(unsigned long)_PAGE_WRITE, (atomic_long_t *)ptep);
+}
+
+#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
+static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep)
+{
+ /*
+ * This comment is borrowed from x86, but applies equally to RISC-V:
+ *
+ * Clearing the accessed bit without a TLB flush
+ * doesn't cause data corruption. [ It could cause incorrect
+ * page aging and the (mistaken) reclaim of hot pages, but the
+ * chance of that should be relatively low. ]
+ *
+ * So as a performance optimization don't flush the TLB when
+ * clearing the accessed bit, it will eventually be flushed by
+ * a context switch or a VM operation anyway. [ In the rare
+ * event of it not getting flushed for a long time the delay
+ * shouldn't really matter because there's no real memory
+ * pressure for swapout to react to. ]
+ */
+ return ptep_test_and_clear_young(vma, address, ptep);
+}
+
+#define pgprot_noncached pgprot_noncached
+static inline pgprot_t pgprot_noncached(pgprot_t _prot)
+{
+ unsigned long prot = pgprot_val(_prot);
+
+ prot &= ~_PAGE_MTMASK;
+ prot |= _PAGE_IO;
+
+ return __pgprot(prot);
+}
+
+#define pgprot_writecombine pgprot_writecombine
+static inline pgprot_t pgprot_writecombine(pgprot_t _prot)
+{
+ unsigned long prot = pgprot_val(_prot);
+
+ prot &= ~_PAGE_MTMASK;
+ prot |= _PAGE_NOCACHE;
+
+ return __pgprot(prot);
+}
+
+/*
+ * THP functions
+ */
+static inline pmd_t pte_pmd(pte_t pte)
+{
+ return __pmd(pte_val(pte));
+}
+
+static inline pmd_t pmd_mkhuge(pmd_t pmd)
+{
+ return pmd;
+}
+
+static inline pmd_t pmd_mkinvalid(pmd_t pmd)
+{
+ return __pmd(pmd_val(pmd) & ~(_PAGE_PRESENT|_PAGE_PROT_NONE));
+}
+
+#define __pmd_to_phys(pmd) (__page_val_to_pfn(pmd_val(pmd)) << PAGE_SHIFT)
+
+static inline unsigned long pmd_pfn(pmd_t pmd)
+{
+ return ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT);
+}
+
+#define __pud_to_phys(pud) (__page_val_to_pfn(pud_val(pud)) << PAGE_SHIFT)
+
+static inline unsigned long pud_pfn(pud_t pud)
+{
+ return ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT);
+}
+
+static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
+{
+ return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
+}
+
+#define pmd_write pmd_write
+static inline int pmd_write(pmd_t pmd)
+{
+ return pte_write(pmd_pte(pmd));
+}
+
+static inline int pmd_dirty(pmd_t pmd)
+{
+ return pte_dirty(pmd_pte(pmd));
+}
+
+#define pmd_young pmd_young
+static inline int pmd_young(pmd_t pmd)
+{
+ return pte_young(pmd_pte(pmd));
+}
+
+static inline int pmd_user(pmd_t pmd)
+{
+ return pte_user(pmd_pte(pmd));
+}
+
+static inline pmd_t pmd_mkold(pmd_t pmd)
+{
+ return pte_pmd(pte_mkold(pmd_pte(pmd)));
+}
+
+static inline pmd_t pmd_mkyoung(pmd_t pmd)
+{
+ return pte_pmd(pte_mkyoung(pmd_pte(pmd)));
+}
+
+static inline pmd_t pmd_mkwrite_novma(pmd_t pmd)
+{
+ return pte_pmd(pte_mkwrite_novma(pmd_pte(pmd)));
+}
+
+static inline pmd_t pmd_wrprotect(pmd_t pmd)
+{
+ return pte_pmd(pte_wrprotect(pmd_pte(pmd)));
+}
+
+static inline pmd_t pmd_mkclean(pmd_t pmd)
+{
+ return pte_pmd(pte_mkclean(pmd_pte(pmd)));
+}
+
+static inline pmd_t pmd_mkdirty(pmd_t pmd)
+{
+ return pte_pmd(pte_mkdirty(pmd_pte(pmd)));
+}
+
+static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
+ pmd_t *pmdp, pmd_t pmd)
+{
+ page_table_check_pmd_set(mm, pmdp, pmd);
+ return __set_pte_at((pte_t *)pmdp, pmd_pte(pmd));
+}
+
+static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
+ pud_t *pudp, pud_t pud)
+{
+ page_table_check_pud_set(mm, pudp, pud);
+ return __set_pte_at((pte_t *)pudp, pud_pte(pud));
+}
+
+#ifdef CONFIG_PAGE_TABLE_CHECK
+static inline bool pte_user_accessible_page(pte_t pte)
+{
+ return pte_present(pte) && pte_user(pte);
+}
+
+static inline bool pmd_user_accessible_page(pmd_t pmd)
+{
+ return pmd_leaf(pmd) && pmd_user(pmd);
+}
+
+static inline bool pud_user_accessible_page(pud_t pud)
+{
+ return pud_leaf(pud) && pud_user(pud);
+}
+#endif
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline int pmd_trans_huge(pmd_t pmd)
+{
+ return pmd_leaf(pmd);
+}
+
+#define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
+static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp,
+ pmd_t entry, int dirty)
+{
+ return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty);
+}
+
+#define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
+static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp)
+{
+ return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
+}
+
+#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
+static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
+ unsigned long address, pmd_t *pmdp)
+{
+ pmd_t pmd = __pmd(atomic_long_xchg((atomic_long_t *)pmdp, 0));
+
+ page_table_check_pmd_clear(mm, pmd);
+
+ return pmd;
+}
+
+#define __HAVE_ARCH_PMDP_SET_WRPROTECT
+static inline void pmdp_set_wrprotect(struct mm_struct *mm,
+ unsigned long address, pmd_t *pmdp)
+{
+ ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
+}
+
+#define pmdp_establish pmdp_establish
+static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp, pmd_t pmd)
+{
+ page_table_check_pmd_set(vma->vm_mm, pmdp, pmd);
+ return __pmd(atomic_long_xchg((atomic_long_t *)pmdp, pmd_val(pmd)));
+}
+
+#define pmdp_collapse_flush pmdp_collapse_flush
+extern pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp);
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
+/*
+ * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
+ * are !pte_none() && !pte_present().
+ *
+ * Format of swap PTE:
+ * bit 0: _PAGE_PRESENT (zero)
+ * bit 1 to 3: _PAGE_LEAF (zero)
+ * bit 5: _PAGE_PROT_NONE (zero)
+ * bit 6: exclusive marker
+ * bits 7 to 11: swap type
+ * bits 11 to XLEN-1: swap offset
+ */
+#define __SWP_TYPE_SHIFT 7
+#define __SWP_TYPE_BITS 5
+#define __SWP_TYPE_MASK ((1UL << __SWP_TYPE_BITS) - 1)
+#define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
+
+#define MAX_SWAPFILES_CHECK() \
+ BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
+
+#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_MASK) << __SWP_TYPE_SHIFT) | \
+ ((offset) << __SWP_OFFSET_SHIFT) })
+
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
+
+static inline int pte_swp_exclusive(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_SWP_EXCLUSIVE;
+}
+
+static inline pte_t pte_swp_mkexclusive(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_SWP_EXCLUSIVE);
+}
+
+static inline pte_t pte_swp_clear_exclusive(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_SWP_EXCLUSIVE);
+}
+
+#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
+#define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })
+#define __swp_entry_to_pmd(swp) __pmd((swp).val)
+#endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
+
+/*
+ * In the RV64 Linux scheme, we give the user half of the virtual-address space
+ * and give the kernel the other (upper) half.
+ */
+#ifdef CONFIG_64BIT
+#define KERN_VIRT_START (-(BIT(VA_BITS)) + TASK_SIZE)
+#else
+#define KERN_VIRT_START FIXADDR_START
+#endif
+
+/*
+ * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32.
+ * Note that PGDIR_SIZE must evenly divide TASK_SIZE.
+ * Task size is:
+ * - 0x9fc00000 (~2.5GB) for RV32.
+ * - 0x4000000000 ( 256GB) for RV64 using SV39 mmu
+ * - 0x800000000000 ( 128TB) for RV64 using SV48 mmu
+ * - 0x100000000000000 ( 64PB) for RV64 using SV57 mmu
+ *
+ * Note that PGDIR_SIZE must evenly divide TASK_SIZE since "RISC-V
+ * Instruction Set Manual Volume II: Privileged Architecture" states that
+ * "load and store effective addresses, which are 64bits, must have bits
+ * 63–48 all equal to bit 47, or else a page-fault exception will occur."
+ * Similarly for SV57, bits 63–57 must be equal to bit 56.
+ */
+#ifdef CONFIG_64BIT
+#define TASK_SIZE_64 (PGDIR_SIZE * PTRS_PER_PGD / 2)
+#define TASK_SIZE_MIN (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
+
+#ifdef CONFIG_COMPAT
+#define TASK_SIZE_32 (_AC(0x80000000, UL))
+#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
+ TASK_SIZE_32 : TASK_SIZE_64)
+#else
+#define TASK_SIZE TASK_SIZE_64
+#endif
+
+#else
+#define TASK_SIZE FIXADDR_START
+#define TASK_SIZE_MIN TASK_SIZE
+#endif
+
+#else /* CONFIG_MMU */
+
+#define PAGE_SHARED __pgprot(0)
+#define PAGE_KERNEL __pgprot(0)
+#define swapper_pg_dir NULL
+#define TASK_SIZE 0xffffffffUL
+#define VMALLOC_START 0
+#define VMALLOC_END TASK_SIZE
+
+#endif /* !CONFIG_MMU */
+
+extern char _start[];
+extern void *_dtb_early_va;
+extern uintptr_t _dtb_early_pa;
+#if defined(CONFIG_XIP_KERNEL) && defined(CONFIG_MMU)
+#define dtb_early_va (*(void **)XIP_FIXUP(&_dtb_early_va))
+#define dtb_early_pa (*(uintptr_t *)XIP_FIXUP(&_dtb_early_pa))
+#else
+#define dtb_early_va _dtb_early_va
+#define dtb_early_pa _dtb_early_pa
+#endif /* CONFIG_XIP_KERNEL */
+extern u64 satp_mode;
+extern bool pgtable_l4_enabled;
+
+void paging_init(void);
+void misc_mem_init(void);
+
+/*
+ * ZERO_PAGE is a global shared page that is always zero,
+ * used for zero-mapped memory areas, etc.
+ */
+extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
+#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_PGTABLE_H */