1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __UM_TLB_H 3 #define __UM_TLB_H 4 5 #include <linux/pagemap.h> 6 #include <linux/swap.h> 7 #include <asm/percpu.h> 8 #include <asm/pgalloc.h> 9 #include <asm/tlbflush.h> 10 11 #define tlb_start_vma(tlb, vma) do { } while (0) 12 #define tlb_end_vma(tlb, vma) do { } while (0) 13 #define tlb_flush(tlb) flush_tlb_mm((tlb)->mm) 14 15 /* struct mmu_gather is an opaque type used by the mm code for passing around 16 * any data needed by arch specific code for tlb_remove_page. 17 */ 18 struct mmu_gather { 19 struct mm_struct *mm; 20 unsigned int need_flush; /* Really unmapped some ptes? */ 21 unsigned long start; 22 unsigned long end; 23 unsigned int fullmm; /* non-zero means full mm flush */ 24 }; 25 26 static inline void __tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, 27 unsigned long address) 28 { 29 if (tlb->start > address) 30 tlb->start = address; 31 if (tlb->end < address + PAGE_SIZE) 32 tlb->end = address + PAGE_SIZE; 33 } 34 35 static inline void init_tlb_gather(struct mmu_gather *tlb) 36 { 37 tlb->need_flush = 0; 38 39 tlb->start = TASK_SIZE; 40 tlb->end = 0; 41 42 if (tlb->fullmm) { 43 tlb->start = 0; 44 tlb->end = TASK_SIZE; 45 } 46 } 47 48 static inline void 49 arch_tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, 50 unsigned long start, unsigned long end) 51 { 52 tlb->mm = mm; 53 tlb->start = start; 54 tlb->end = end; 55 tlb->fullmm = !(start | (end+1)); 56 57 init_tlb_gather(tlb); 58 } 59 60 extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, 61 unsigned long end); 62 63 static inline void 64 tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) 65 { 66 flush_tlb_mm_range(tlb->mm, tlb->start, tlb->end); 67 } 68 69 static inline void 70 tlb_flush_mmu_free(struct mmu_gather *tlb) 71 { 72 init_tlb_gather(tlb); 73 } 74 75 static inline void 76 tlb_flush_mmu(struct mmu_gather *tlb) 77 { 78 if (!tlb->need_flush) 79 return; 80 81 tlb_flush_mmu_tlbonly(tlb); 82 tlb_flush_mmu_free(tlb); 83 } 84 85 /* arch_tlb_finish_mmu 86 * Called at the end of the shootdown operation to free up any resources 87 * that were required. 88 */ 89 static inline void 90 arch_tlb_finish_mmu(struct mmu_gather *tlb, 91 unsigned long start, unsigned long end, bool force) 92 { 93 if (force) { 94 tlb->start = start; 95 tlb->end = end; 96 tlb->need_flush = 1; 97 } 98 tlb_flush_mmu(tlb); 99 100 /* keep the page table cache within bounds */ 101 check_pgt_cache(); 102 } 103 104 /* tlb_remove_page 105 * Must perform the equivalent to __free_pte(pte_get_and_clear(ptep)), 106 * while handling the additional races in SMP caused by other CPUs 107 * caching valid mappings in their TLBs. 108 */ 109 static inline int __tlb_remove_page(struct mmu_gather *tlb, struct page *page) 110 { 111 tlb->need_flush = 1; 112 free_page_and_swap_cache(page); 113 return false; /* avoid calling tlb_flush_mmu */ 114 } 115 116 static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page) 117 { 118 __tlb_remove_page(tlb, page); 119 } 120 121 static inline bool __tlb_remove_page_size(struct mmu_gather *tlb, 122 struct page *page, int page_size) 123 { 124 return __tlb_remove_page(tlb, page); 125 } 126 127 static inline void tlb_remove_page_size(struct mmu_gather *tlb, 128 struct page *page, int page_size) 129 { 130 return tlb_remove_page(tlb, page); 131 } 132 133 /** 134 * tlb_remove_tlb_entry - remember a pte unmapping for later tlb invalidation. 135 * 136 * Record the fact that pte's were really umapped in ->need_flush, so we can 137 * later optimise away the tlb invalidate. This helps when userspace is 138 * unmapping already-unmapped pages, which happens quite a lot. 139 */ 140 #define tlb_remove_tlb_entry(tlb, ptep, address) \ 141 do { \ 142 tlb->need_flush = 1; \ 143 __tlb_remove_tlb_entry(tlb, ptep, address); \ 144 } while (0) 145 146 #define tlb_remove_huge_tlb_entry(h, tlb, ptep, address) \ 147 tlb_remove_tlb_entry(tlb, ptep, address) 148 149 #define tlb_remove_check_page_size_change tlb_remove_check_page_size_change 150 static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb, 151 unsigned int page_size) 152 { 153 } 154 155 #define pte_free_tlb(tlb, ptep, addr) __pte_free_tlb(tlb, ptep, addr) 156 157 #define pud_free_tlb(tlb, pudp, addr) __pud_free_tlb(tlb, pudp, addr) 158 159 #define pmd_free_tlb(tlb, pmdp, addr) __pmd_free_tlb(tlb, pmdp, addr) 160 161 #define tlb_migrate_finish(mm) do {} while (0) 162 163 #endif 164