LXR linux/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/cache.h>
  26#include <asm/tlbflush.h>
  27
  28void sync_icache_aliases(void *kaddr, unsigned long len)
  29{
  30        unsigned long addr = (unsigned long)kaddr;
  31
  32        if (icache_is_aliasing()) {
  33                __clean_dcache_area_pou(kaddr, len);
  34                __flush_icache_all();
  35        } else {
  36                flush_icache_range(addr, addr + len);
  37        }
  38}
  39
  40static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
  41                                unsigned long uaddr, void *kaddr,
  42                                unsigned long len)
  43{
  44        if (vma->vm_flags & VM_EXEC)
  45                sync_icache_aliases(kaddr, len);
  46}
  47
  48/*
  49 * Copy user data from/to a page which is mapped into a different processes
  50 * address space.  Really, we want to allow our "user space" model to handle
  51 * this.
  52 */
  53void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
  54                       unsigned long uaddr, void *dst, const void *src,
  55                       unsigned long len)
  56{
  57        memcpy(dst, src, len);
  58        flush_ptrace_access(vma, page, uaddr, dst, len);
  59}
  60
  61void __sync_icache_dcache(pte_t pte, unsigned long addr)
  62{
  63        struct page *page = pte_page(pte);
  64
  65        if (!test_and_set_bit(PG_dcache_clean, &page->flags))
  66                sync_icache_aliases(page_address(page),
  67                                    PAGE_SIZE << compound_order(page));
  68}
  69
  70/*
  71 * This function is called when a page has been modified by the kernel. Mark
  72 * it as dirty for later flushing when mapped in user space (if executable,
  73 * see __sync_icache_dcache).
  74 */
  75void flush_dcache_page(struct page *page)
  76{
  77        if (test_bit(PG_dcache_clean, &page->flags))
  78                clear_bit(PG_dcache_clean, &page->flags);
  79}
  80EXPORT_SYMBOL(flush_dcache_page);
  81
  82/*
  83 * Additional functions defined in assembly.
  84 */
  85EXPORT_SYMBOL(flush_icache_range);
  86