xref: /openbmc/linux/arch/arm64/mm/flush.c (revision 44900c3e)
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/libnvdimm.h>
12 #include <linux/pagemap.h>
13 
14 #include <asm/cacheflush.h>
15 #include <asm/cache.h>
16 #include <asm/tlbflush.h>
17 
18 void sync_icache_aliases(unsigned long start, unsigned long end)
19 {
20 	if (icache_is_aliasing()) {
21 		dcache_clean_pou(start, end);
22 		icache_inval_all_pou();
23 	} else {
24 		/*
25 		 * Don't issue kick_all_cpus_sync() after I-cache invalidation
26 		 * for user mappings.
27 		 */
28 		caches_clean_inval_pou(start, end);
29 	}
30 }
31 
32 static void flush_ptrace_access(struct vm_area_struct *vma, unsigned long start,
33 				unsigned long end)
34 {
35 	if (vma->vm_flags & VM_EXEC)
36 		sync_icache_aliases(start, end);
37 }
38 
39 /*
40  * Copy user data from/to a page which is mapped into a different processes
41  * address space.  Really, we want to allow our "user space" model to handle
42  * this.
43  */
44 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
45 		       unsigned long uaddr, void *dst, const void *src,
46 		       unsigned long len)
47 {
48 	memcpy(dst, src, len);
49 	flush_ptrace_access(vma, (unsigned long)dst, (unsigned long)dst + len);
50 }
51 
52 void __sync_icache_dcache(pte_t pte)
53 {
54 	struct page *page = pte_page(pte);
55 
56 	/*
57 	 * HugeTLB pages are always fully mapped, so only setting head page's
58 	 * PG_dcache_clean flag is enough.
59 	 */
60 	if (PageHuge(page))
61 		page = compound_head(page);
62 
63 	if (!test_bit(PG_dcache_clean, &page->flags)) {
64 		sync_icache_aliases((unsigned long)page_address(page),
65 				    (unsigned long)page_address(page) +
66 					    page_size(page));
67 		set_bit(PG_dcache_clean, &page->flags);
68 	}
69 }
70 EXPORT_SYMBOL_GPL(__sync_icache_dcache);
71 
72 /*
73  * This function is called when a page has been modified by the kernel. Mark
74  * it as dirty for later flushing when mapped in user space (if executable,
75  * see __sync_icache_dcache).
76  */
77 void flush_dcache_page(struct page *page)
78 {
79 	/*
80 	 * HugeTLB pages are always fully mapped and only head page will be
81 	 * set PG_dcache_clean (see comments in __sync_icache_dcache()).
82 	 */
83 	if (PageHuge(page))
84 		page = compound_head(page);
85 
86 	if (test_bit(PG_dcache_clean, &page->flags))
87 		clear_bit(PG_dcache_clean, &page->flags);
88 }
89 EXPORT_SYMBOL(flush_dcache_page);
90 
91 /*
92  * Additional functions defined in assembly.
93  */
94 EXPORT_SYMBOL(caches_clean_inval_pou);
95 
96 #ifdef CONFIG_ARCH_HAS_PMEM_API
97 void arch_wb_cache_pmem(void *addr, size_t size)
98 {
99 	/* Ensure order against any prior non-cacheable writes */
100 	dmb(osh);
101 	dcache_clean_pop((unsigned long)addr, (unsigned long)addr + size);
102 }
103 EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
104 
105 void arch_invalidate_pmem(void *addr, size_t size)
106 {
107 	dcache_inval_poc((unsigned long)addr, (unsigned long)addr + size);
108 }
109 EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
110 #endif
111