1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Based on arch/arm/mm/flush.c 4 * 5 * Copyright (C) 1995-2002 Russell King 6 * Copyright (C) 2012 ARM Ltd. 7 */ 8 9 #include <linux/export.h> 10 #include <linux/mm.h> 11 #include <linux/pagemap.h> 12 13 #include <asm/cacheflush.h> 14 #include <asm/cache.h> 15 #include <asm/tlbflush.h> 16 17 void sync_icache_aliases(unsigned long start, unsigned long end) 18 { 19 if (icache_is_aliasing()) { 20 dcache_clean_pou(start, end); 21 icache_inval_all_pou(); 22 } else { 23 /* 24 * Don't issue kick_all_cpus_sync() after I-cache invalidation 25 * for user mappings. 26 */ 27 caches_clean_inval_pou(start, end); 28 } 29 } 30 31 static void flush_ptrace_access(struct vm_area_struct *vma, unsigned long start, 32 unsigned long end) 33 { 34 if (vma->vm_flags & VM_EXEC) 35 sync_icache_aliases(start, end); 36 } 37 38 /* 39 * Copy user data from/to a page which is mapped into a different processes 40 * address space. Really, we want to allow our "user space" model to handle 41 * this. 42 */ 43 void copy_to_user_page(struct vm_area_struct *vma, struct page *page, 44 unsigned long uaddr, void *dst, const void *src, 45 unsigned long len) 46 { 47 memcpy(dst, src, len); 48 flush_ptrace_access(vma, (unsigned long)dst, (unsigned long)dst + len); 49 } 50 51 void __sync_icache_dcache(pte_t pte) 52 { 53 struct page *page = pte_page(pte); 54 55 /* 56 * HugeTLB pages are always fully mapped, so only setting head page's 57 * PG_dcache_clean flag is enough. 58 */ 59 if (PageHuge(page)) 60 page = compound_head(page); 61 62 if (!test_bit(PG_dcache_clean, &page->flags)) { 63 sync_icache_aliases((unsigned long)page_address(page), 64 (unsigned long)page_address(page) + 65 page_size(page)); 66 set_bit(PG_dcache_clean, &page->flags); 67 } 68 } 69 EXPORT_SYMBOL_GPL(__sync_icache_dcache); 70 71 /* 72 * This function is called when a page has been modified by the kernel. Mark 73 * it as dirty for later flushing when mapped in user space (if executable, 74 * see __sync_icache_dcache). 75 */ 76 void flush_dcache_page(struct page *page) 77 { 78 /* 79 * Only the head page's flags of HugeTLB can be cleared since the tail 80 * vmemmap pages associated with each HugeTLB page are mapped with 81 * read-only when CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP is enabled (more 82 * details can refer to vmemmap_remap_pte()). Although 83 * __sync_icache_dcache() only set PG_dcache_clean flag on the head 84 * page struct, there is more than one page struct with PG_dcache_clean 85 * associated with the HugeTLB page since the head vmemmap page frame 86 * is reused (more details can refer to the comments above 87 * page_fixed_fake_head()). 88 */ 89 if (hugetlb_optimize_vmemmap_enabled() && PageHuge(page)) 90 page = compound_head(page); 91 92 if (test_bit(PG_dcache_clean, &page->flags)) 93 clear_bit(PG_dcache_clean, &page->flags); 94 } 95 EXPORT_SYMBOL(flush_dcache_page); 96 97 /* 98 * Additional functions defined in assembly. 99 */ 100 EXPORT_SYMBOL(caches_clean_inval_pou); 101 102 #ifdef CONFIG_ARCH_HAS_PMEM_API 103 void arch_wb_cache_pmem(void *addr, size_t size) 104 { 105 /* Ensure order against any prior non-cacheable writes */ 106 dmb(osh); 107 dcache_clean_pop((unsigned long)addr, (unsigned long)addr + size); 108 } 109 EXPORT_SYMBOL_GPL(arch_wb_cache_pmem); 110 111 void arch_invalidate_pmem(void *addr, size_t size) 112 { 113 dcache_inval_poc((unsigned long)addr, (unsigned long)addr + size); 114 } 115 EXPORT_SYMBOL_GPL(arch_invalidate_pmem); 116 #endif 117