arch/arm64/mm/flush.c

   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 void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
  29                        unsigned long end)
  30 {
  31         if (vma->vm_flags & VM_EXEC)
  32                 __flush_icache_all();
  33 }
  34
  35 static void sync_icache_aliases(void *kaddr, unsigned long len)
  36 {
  37         unsigned long addr = (unsigned long)kaddr;
  38
  39         if (icache_is_aliasing()) {
  40                 __clean_dcache_area_pou(kaddr, len);
  41                 __flush_icache_all();
  42         } else {
  43                 flush_icache_range(addr, addr + len);
  44         }
  45 }
  46
  47 static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
  48                                 unsigned long uaddr, void *kaddr,
  49                                 unsigned long len)
  50 {
  51         if (vma->vm_flags & VM_EXEC)
  52                 sync_icache_aliases(kaddr, len);
  53 }
  54
  55 /*
  56  * Copy user data from/to a page which is mapped into a different processes
  57  * address space.  Really, we want to allow our "user space" model to handle
  58  * this.
  59  */
  60 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
  61                        unsigned long uaddr, void *dst, const void *src,
  62                        unsigned long len)
  63 {
  64         memcpy(dst, src, len);
  65         flush_ptrace_access(vma, page, uaddr, dst, len);
  66 }
  67
  68 void __sync_icache_dcache(pte_t pte, unsigned long addr)
  69 {
  70         struct page *page = pte_page(pte);
  71
  72         if (!test_and_set_bit(PG_dcache_clean, &page->flags))
  73                 sync_icache_aliases(page_address(page),
  74                                     PAGE_SIZE << compound_order(page));
  75         else if (icache_is_aivivt())
  76                 __flush_icache_all();
  77 }
  78
  79 /*
  80  * This function is called when a page has been modified by the kernel. Mark
  81  * it as dirty for later flushing when mapped in user space (if executable,
  82  * see __sync_icache_dcache).
  83  */
  84 void flush_dcache_page(struct page *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(flush_icache_range);