diff options
Diffstat (limited to 'arch/riscv/include/asm/pgtable.h')
| -rw-r--r-- | arch/riscv/include/asm/pgtable.h | 835 |
1 files changed, 835 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..59bb53da4 --- /dev/null +++ b/arch/riscv/include/asm/pgtable.h @@ -0,0 +1,835 @@ +/* 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 (half 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. + */ +#ifdef CONFIG_64BIT +#define VA_BITS (pgtable_l5_enabled ? \ + 57 : (pgtable_l4_enabled ? 48 : 39)) +#else +#define VA_BITS 32 +#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> + +#define __page_val_to_pfn(_val) (((_val) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT) + +#ifdef CONFIG_64BIT +#include <asm/pgtable-64.h> +#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[]; + +#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)); +} + +/* Yields the page frame number (PFN) of a page table entry */ +static inline unsigned long pte_pfn(pte_t pte) +{ + return __page_val_to_pfn(pte_val(pte)); +} + +#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(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(struct vm_area_struct *vma, + unsigned long address, pte_t *ptep) +{ + /* + * 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. + */ + local_flush_tlb_page(address); +} + +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(struct mm_struct *mm, + unsigned long addr, 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_pte_at(struct mm_struct *mm, + unsigned long addr, pte_t *ptep, pte_t pteval) +{ + page_table_check_pte_set(mm, addr, ptep, pteval); + __set_pte_at(mm, addr, ptep, pteval); +} + +static inline void pte_clear(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + __set_pte_at(mm, addr, 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(vma->vm_mm, address, 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, address, 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(pmd_t pmd) +{ + return pte_pmd(pte_mkwrite(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, addr, pmdp, pmd); + return __set_pte_at(mm, addr, (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, addr, pudp, pud); + return __set_pte_at(mm, addr, (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, address, 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, address, pmdp, pmd); + return __pmd(atomic_long_xchg((atomic_long_t *)pmdp, pmd_val(pmd))); +} +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ + +/* + * Encode and decode a swap entry + * + * Format of swap PTE: + * bit 0: _PAGE_PRESENT (zero) + * bit 1 to 3: _PAGE_LEAF (zero) + * bit 5: _PAGE_PROT_NONE (zero) + * bits 6 to 10: swap type + * bits 10 to XLEN-1: swap offset + */ +#define __SWP_TYPE_SHIFT 6 +#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_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 }) + +#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 + * + * 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." + */ +#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) - PAGE_SIZE) +#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 */ + +#define kern_addr_valid(addr) (1) /* FIXME */ + +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 */ |