1 /* 2 * Based on arch/arm/mm/flush.c 3 * 4 * Copyright (C) 1995-2002 Russell King 5 * Copyright (C) 2012 ARM Ltd. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include <linux/export.h> 21 #include <linux/mm.h> 22 #include <linux/pagemap.h> 23 24 #include <asm/cacheflush.h> 25 #include <asm/cachetype.h> 26 #include <asm/tlbflush.h> 27 28 #include "mm.h" 29 30 void flush_cache_range(struct vm_area_struct *vma, unsigned long start, 31 unsigned long end) 32 { 33 if (vma->vm_flags & VM_EXEC) 34 __flush_icache_all(); 35 } 36 37 static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page, 38 unsigned long uaddr, void *kaddr, 39 unsigned long len) 40 { 41 if (vma->vm_flags & VM_EXEC) { 42 unsigned long addr = (unsigned long)kaddr; 43 if (icache_is_aliasing()) { 44 __flush_dcache_area(kaddr, len); 45 __flush_icache_all(); 46 } else { 47 flush_icache_range(addr, addr + len); 48 } 49 } 50 } 51 52 /* 53 * Copy user data from/to a page which is mapped into a different processes 54 * address space. Really, we want to allow our "user space" model to handle 55 * this. 56 * 57 * Note that this code needs to run on the current CPU. 58 */ 59 void copy_to_user_page(struct vm_area_struct *vma, struct page *page, 60 unsigned long uaddr, void *dst, const void *src, 61 unsigned long len) 62 { 63 #ifdef CONFIG_SMP 64 preempt_disable(); 65 #endif 66 memcpy(dst, src, len); 67 flush_ptrace_access(vma, page, uaddr, dst, len); 68 #ifdef CONFIG_SMP 69 preempt_enable(); 70 #endif 71 } 72 73 void __sync_icache_dcache(pte_t pte, unsigned long addr) 74 { 75 struct page *page = pte_page(pte); 76 77 /* no flushing needed for anonymous pages */ 78 if (!page_mapping(page)) 79 return; 80 81 if (!test_and_set_bit(PG_dcache_clean, &page->flags)) { 82 __flush_dcache_area(page_address(page), 83 PAGE_SIZE << compound_order(page)); 84 __flush_icache_all(); 85 } else if (icache_is_aivivt()) { 86 __flush_icache_all(); 87 } 88 } 89 90 /* 91 * This function is called when a page has been modified by the kernel. Mark 92 * it as dirty for later flushing when mapped in user space (if executable, 93 * see __sync_icache_dcache). 94 */ 95 void flush_dcache_page(struct page *page) 96 { 97 if (test_bit(PG_dcache_clean, &page->flags)) 98 clear_bit(PG_dcache_clean, &page->flags); 99 } 100 EXPORT_SYMBOL(flush_dcache_page); 101 102 /* 103 * Additional functions defined in assembly. 104 */ 105 EXPORT_SYMBOL(flush_cache_all); 106 EXPORT_SYMBOL(flush_icache_range); 107 108 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 109 #ifdef CONFIG_HAVE_RCU_TABLE_FREE 110 void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, 111 pmd_t *pmdp) 112 { 113 pmd_t pmd = pmd_mksplitting(*pmdp); 114 115 VM_BUG_ON(address & ~PMD_MASK); 116 set_pmd_at(vma->vm_mm, address, pmdp, pmd); 117 118 /* dummy IPI to serialise against fast_gup */ 119 kick_all_cpus_sync(); 120 } 121 #endif /* CONFIG_HAVE_RCU_TABLE_FREE */ 122 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 123