arch/arm64/include/asm/cacheflush.h

   1 /*
   2  * Based on arch/arm/include/asm/cacheflush.h
   3  *
   4  * Copyright (C) 1999-2002 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 #ifndef __ASM_CACHEFLUSH_H
  20 #define __ASM_CACHEFLUSH_H
  21
  22 #include <linux/mm.h>
  23
  24 /*
  25  * This flag is used to indicate that the page pointed to by a pte is clean
  26  * and does not require cleaning before returning it to the user.
  27  */
  28 #define PG_dcache_clean PG_arch_1
  29
  30 /*
  31  *      MM Cache Management
  32  *      ===================
  33  *
  34  *      The arch/arm64/mm/cache.S implements these methods.
  35  *
  36  *      Start addresses are inclusive and end addresses are exclusive; start
  37  *      addresses should be rounded down, end addresses up.
  38  *
  39  *      See Documentation/cachetlb.txt for more information. Please note that
  40  *      the implementation assumes non-aliasing VIPT D-cache and (aliasing)
  41  *      VIPT or ASID-tagged VIVT I-cache.
  42  *
  43  *      flush_cache_all()
  44  *
  45  *              Unconditionally clean and invalidate the entire cache.
  46  *
  47  *      flush_cache_mm(mm)
  48  *
  49  *              Clean and invalidate all user space cache entries
  50  *              before a change of page tables.
  51  *
  52  *      flush_icache_range(start, end)
  53  *
  54  *              Ensure coherency between the I-cache and the D-cache in the
  55  *              region described by start, end.
  56  *              - start  - virtual start address
  57  *              - end    - virtual end address
  58  *
  59  *      __flush_cache_user_range(start, end)
  60  *
  61  *              Ensure coherency between the I-cache and the D-cache in the
  62  *              region described by start, end.
  63  *              - start  - virtual start address
  64  *              - end    - virtual end address
  65  *
  66  *      __flush_dcache_area(kaddr, size)
  67  *
  68  *              Ensure that the data held in page is written back.
  69  *              - kaddr  - page address
  70  *              - size   - region size
  71  */
  72 extern void flush_cache_all(void);
  73 extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
  74 extern void flush_icache_range(unsigned long start, unsigned long end);
  75 extern void __flush_dcache_area(void *addr, size_t len);
  76 extern void __flush_cache_user_range(unsigned long start, unsigned long end);
  77
  78 static inline void flush_cache_mm(struct mm_struct *mm)
  79 {
  80 }
  81
  82 static inline void flush_cache_page(struct vm_area_struct *vma,
  83                                     unsigned long user_addr, unsigned long pfn)
  84 {
  85 }
  86
  87 /*
  88  * Copy user data from/to a page which is mapped into a different
  89  * processes address space.  Really, we want to allow our "user
  90  * space" model to handle this.
  91  */
  92 extern void copy_to_user_page(struct vm_area_struct *, struct page *,
  93         unsigned long, void *, const void *, unsigned long);
  94 #define copy_from_user_page(vma, page, vaddr, dst, src, len) \
  95         do {                                                    \
  96                 memcpy(dst, src, len);                          \
  97         } while (0)
  98
  99 #define flush_cache_dup_mm(mm) flush_cache_mm(mm)
 100
 101 /*
 102  * flush_dcache_page is used when the kernel has written to the page
 103  * cache page at virtual address page->virtual.
 104  *
 105  * If this page isn't mapped (ie, page_mapping == NULL), or it might
 106  * have userspace mappings, then we _must_ always clean + invalidate
 107  * the dcache entries associated with the kernel mapping.
 108  *
 109  * Otherwise we can defer the operation, and clean the cache when we are
 110  * about to change to user space.  This is the same method as used on SPARC64.
 111  * See update_mmu_cache for the user space part.
 112  */
 113 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 114 extern void flush_dcache_page(struct page *);
 115
 116 static inline void __flush_icache_all(void)
 117 {
 118         asm("ic ialluis");
 119         dsb();
 120 }
 121
 122 #define flush_dcache_mmap_lock(mapping) \
 123         spin_lock_irq(&(mapping)->tree_lock)
 124 #define flush_dcache_mmap_unlock(mapping) \
 125         spin_unlock_irq(&(mapping)->tree_lock)
 126
 127 /*
 128  * We don't appear to need to do anything here.  In fact, if we did, we'd
 129  * duplicate cache flushing elsewhere performed by flush_dcache_page().
 130  */
 131 #define flush_icache_page(vma,page)     do { } while (0)
 132
 133 /*
 134  * flush_cache_vmap() is used when creating mappings (eg, via vmap,
 135  * vmalloc, ioremap etc) in kernel space for pages.  On non-VIPT
 136  * caches, since the direct-mappings of these pages may contain cached
 137  * data, we need to do a full cache flush to ensure that writebacks
 138  * don't corrupt data placed into these pages via the new mappings.
 139  */
 140 static inline void flush_cache_vmap(unsigned long start, unsigned long end)
 141 {
 142         /*
 143          * set_pte_at() called from vmap_pte_range() does not
 144          * have a DSB after cleaning the cache line.
 145          */
 146         dsb();
 147 }
 148
 149 static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
 150 {
 151 }
 152
 153 #endif