arch/mips/mm/cache.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1994 - 2003, 06, 07 by Ralf Baechle (ralf@linux-mips.org)
   7  * Copyright (C) 2007 MIPS Technologies, Inc.
   8  */
   9 #include <linux/fs.h>
  10 #include <linux/fcntl.h>
  11 #include <linux/kernel.h>
  12 #include <linux/linkage.h>
  13 #include <linux/export.h>
  14 #include <linux/sched.h>
  15 #include <linux/syscalls.h>
  16 #include <linux/mm.h>
  17 #include <linux/highmem.h>
  18 #include <linux/pagemap.h>
  19
  20 #include <asm/bcache.h>
  21 #include <asm/cacheflush.h>
  22 #include <asm/processor.h>
  23 #include <asm/cpu.h>
  24 #include <asm/cpu-features.h>
  25 #include <asm/setup.h>
  26 #include <asm/pgtable.h>
  27
  28 /* Cache operations. */
  29 void (*flush_cache_all)(void);
  30 void (*__flush_cache_all)(void);
  31 EXPORT_SYMBOL_GPL(__flush_cache_all);
  32 void (*flush_cache_mm)(struct mm_struct *mm);
  33 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
  34         unsigned long end);
  35 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
  36         unsigned long pfn);
  37 void (*flush_icache_range)(unsigned long start, unsigned long end);
  38 EXPORT_SYMBOL_GPL(flush_icache_range);
  39 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
  40 EXPORT_SYMBOL_GPL(local_flush_icache_range);
  41 void (*__flush_icache_user_range)(unsigned long start, unsigned long end);
  42 void (*__local_flush_icache_user_range)(unsigned long start, unsigned long end);
  43 EXPORT_SYMBOL_GPL(__local_flush_icache_user_range);
  44
  45 void (*__flush_cache_vmap)(void);
  46 void (*__flush_cache_vunmap)(void);
  47
  48 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
  49 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
  50
  51 /* MIPS specific cache operations */
  52 void (*flush_data_cache_page)(unsigned long addr);
  53 void (*flush_icache_all)(void);
  54
  55 EXPORT_SYMBOL(flush_data_cache_page);
  56 EXPORT_SYMBOL(flush_icache_all);
  57
  58 /*
  59  * Dummy cache handling routine
  60  */
  61
  62 void cache_noop(void) {}
  63
  64 #ifdef CONFIG_BOARD_SCACHE
  65
  66 static struct bcache_ops no_sc_ops = {
  67         .bc_enable = (void *)cache_noop,
  68         .bc_disable = (void *)cache_noop,
  69         .bc_wback_inv = (void *)cache_noop,
  70         .bc_inv = (void *)cache_noop
  71 };
  72
  73 struct bcache_ops *bcops = &no_sc_ops;
  74 #endif
  75
  76 #ifdef CONFIG_DMA_NONCOHERENT
  77
  78 /* DMA cache operations. */
  79 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
  80 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
  81 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
  82
  83 #endif /* CONFIG_DMA_NONCOHERENT */
  84
  85 /*
  86  * We could optimize the case where the cache argument is not BCACHE but
  87  * that seems very atypical use ...
  88  */
  89 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
  90         unsigned int, cache)
  91 {
  92         if (bytes == 0)
  93                 return 0;
  94         if (!access_ok((void __user *) addr, bytes))
  95                 return -EFAULT;
  96
  97         __flush_icache_user_range(addr, addr + bytes);
  98
  99         return 0;
 100 }
 101
 102 void __flush_dcache_pages(struct page *page, unsigned int nr)
 103 {
 104         struct folio *folio = page_folio(page);
 105         struct address_space *mapping = folio_flush_mapping(folio);
 106         unsigned long addr;
 107         unsigned int i;
 108
 109         if (mapping && !mapping_mapped(mapping)) {
 110                 folio_set_dcache_dirty(folio);
 111                 return;
 112         }
 113
 114         /*
 115          * We could delay the flush for the !page_mapping case too.  But that
 116          * case is for exec env/arg pages and those are %99 certainly going to
 117          * get faulted into the tlb (and thus flushed) anyways.
 118          */
 119         for (i = 0; i < nr; i++) {
 120                 addr = (unsigned long)kmap_local_page(nth_page(page, i));
 121                 flush_data_cache_page(addr);
 122                 kunmap_local((void *)addr);
 123         }
 124 }
 125 EXPORT_SYMBOL(__flush_dcache_pages);
 126
 127 void __flush_anon_page(struct page *page, unsigned long vmaddr)
 128 {
 129         unsigned long addr = (unsigned long) page_address(page);
 130         struct folio *folio = page_folio(page);
 131
 132         if (pages_do_alias(addr, vmaddr)) {
 133                 if (folio_mapped(folio) && !folio_test_dcache_dirty(folio)) {
 134                         void *kaddr;
 135
 136                         kaddr = kmap_coherent(page, vmaddr);
 137                         flush_data_cache_page((unsigned long)kaddr);
 138                         kunmap_coherent();
 139                 } else
 140                         flush_data_cache_page(addr);
 141         }
 142 }
 143
 144 EXPORT_SYMBOL(__flush_anon_page);
 145
 146 void __update_cache(unsigned long address, pte_t pte)
 147 {
 148         struct folio *folio;
 149         unsigned long pfn, addr;
 150         int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
 151         unsigned int i;
 152
 153         pfn = pte_pfn(pte);
 154         if (unlikely(!pfn_valid(pfn)))
 155                 return;
 156
 157         folio = page_folio(pfn_to_page(pfn));
 158         address &= PAGE_MASK;
 159         address -= offset_in_folio(folio, pfn << PAGE_SHIFT);
 160
 161         if (folio_test_dcache_dirty(folio)) {
 162                 for (i = 0; i < folio_nr_pages(folio); i++) {
 163                         addr = (unsigned long)kmap_local_folio(folio, i);
 164
 165                         if (exec || pages_do_alias(addr, address))
 166                                 flush_data_cache_page(addr);
 167                         kunmap_local((void *)addr);
 168                         address += PAGE_SIZE;
 169                 }
 170                 folio_clear_dcache_dirty(folio);
 171         }
 172 }
 173
 174 unsigned long _page_cachable_default;
 175 EXPORT_SYMBOL(_page_cachable_default);
 176
 177 #define PM(p)   __pgprot(_page_cachable_default | (p))
 178
 179 static pgprot_t protection_map[16] __ro_after_init;
 180 DECLARE_VM_GET_PAGE_PROT
 181
 182 static inline void setup_protection_map(void)
 183 {
 184         protection_map[0]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 185         protection_map[1]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
 186         protection_map[2]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 187         protection_map[3]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
 188         protection_map[4]  = PM(_PAGE_PRESENT);
 189         protection_map[5]  = PM(_PAGE_PRESENT);
 190         protection_map[6]  = PM(_PAGE_PRESENT);
 191         protection_map[7]  = PM(_PAGE_PRESENT);
 192
 193         protection_map[8]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 194         protection_map[9]  = PM(_PAGE_PRESENT | _PAGE_NO_EXEC);
 195         protection_map[10] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE |
 196                                 _PAGE_NO_READ);
 197         protection_map[11] = PM(_PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
 198         protection_map[12] = PM(_PAGE_PRESENT);
 199         protection_map[13] = PM(_PAGE_PRESENT);
 200         protection_map[14] = PM(_PAGE_PRESENT | _PAGE_WRITE);
 201         protection_map[15] = PM(_PAGE_PRESENT | _PAGE_WRITE);
 202 }
 203
 204 #undef PM
 205
 206 void cpu_cache_init(void)
 207 {
 208         if (cpu_has_3k_cache) {
 209                 extern void __weak r3k_cache_init(void);
 210
 211                 r3k_cache_init();
 212         }
 213         if (cpu_has_4k_cache) {
 214                 extern void __weak r4k_cache_init(void);
 215
 216                 r4k_cache_init();
 217         }
 218
 219         if (cpu_has_octeon_cache) {
 220                 extern void __weak octeon_cache_init(void);
 221
 222                 octeon_cache_init();
 223         }
 224
 225         setup_protection_map();
 226 }