arch/m32r/include/asm/pgtable.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_M32R_PGTABLE_H
   3 #define _ASM_M32R_PGTABLE_H
   4
   5 #include <asm-generic/4level-fixup.h>
   6
   7 #ifdef __KERNEL__
   8 /*
   9  * The Linux memory management assumes a three-level page table setup. On
  10  * the M32R, we use that, but "fold" the mid level into the top-level page
  11  * table, so that we physically have the same two-level page table as the
  12  * M32R mmu expects.
  13  *
  14  * This file contains the functions and defines necessary to modify and use
  15  * the M32R page table tree.
  16  */
  17
  18 /* CAUTION!: If you change macro definitions in this file, you might have to
  19  * change arch/m32r/mmu.S manually.
  20  */
  21
  22 #ifndef __ASSEMBLY__
  23
  24 #include <linux/threads.h>
  25 #include <linux/bitops.h>
  26 #include <asm/processor.h>
  27 #include <asm/addrspace.h>
  28 #include <asm/page.h>
  29
  30 struct mm_struct;
  31 struct vm_area_struct;
  32
  33 extern pgd_t swapper_pg_dir[1024];
  34 extern void paging_init(void);
  35
  36 /*
  37  * ZERO_PAGE is a global shared page that is always zero: used
  38  * for zero-mapped memory areas etc..
  39  */
  40 extern unsigned long empty_zero_page[1024];
  41 #define ZERO_PAGE(vaddr)        (virt_to_page(empty_zero_page))
  42
  43 #endif /* !__ASSEMBLY__ */
  44
  45 #ifndef __ASSEMBLY__
  46 #include <asm/pgtable-2level.h>
  47 #endif
  48
  49 #define pgtable_cache_init()    do { } while (0)
  50
  51 #define PMD_SIZE        (1UL << PMD_SHIFT)
  52 #define PMD_MASK        (~(PMD_SIZE - 1))
  53 #define PGDIR_SIZE      (1UL << PGDIR_SHIFT)
  54 #define PGDIR_MASK      (~(PGDIR_SIZE - 1))
  55
  56 #define USER_PTRS_PER_PGD       (TASK_SIZE / PGDIR_SIZE)
  57 #define FIRST_USER_ADDRESS      0UL
  58
  59 #ifndef __ASSEMBLY__
  60 /* Just any arbitrary offset to the start of the vmalloc VM area: the
  61  * current 8MB value just means that there will be a 8MB "hole" after the
  62  * physical memory until the kernel virtual memory starts.  That means that
  63  * any out-of-bounds memory accesses will hopefully be caught.
  64  * The vmalloc() routines leaves a hole of 4kB between each vmalloced
  65  * area for the same reason. ;)
  66  */
  67 #define VMALLOC_START           KSEG2
  68 #define VMALLOC_END             KSEG3
  69
  70 /*
  71  *     M32R TLB format
  72  *
  73  *     [0]    [1:19]           [20:23]       [24:31]
  74  *     +-----------------------+----+-------------+
  75  *     |          VPN          |0000|    ASID     |
  76  *     +-----------------------+----+-------------+
  77  *     +-+---------------------+----+-+---+-+-+-+-+
  78  *     |0         PPN          |0000|N|AC |L|G|V| |
  79  *     +-+---------------------+----+-+---+-+-+-+-+
  80  *                                     RWX
  81  */
  82
  83 #define _PAGE_BIT_DIRTY         0       /* software: page changed */
  84 #define _PAGE_BIT_PRESENT       1       /* Valid: page is valid */
  85 #define _PAGE_BIT_GLOBAL        2       /* Global */
  86 #define _PAGE_BIT_LARGE         3       /* Large */
  87 #define _PAGE_BIT_EXEC          4       /* Execute */
  88 #define _PAGE_BIT_WRITE         5       /* Write */
  89 #define _PAGE_BIT_READ          6       /* Read */
  90 #define _PAGE_BIT_NONCACHABLE   7       /* Non cachable */
  91 #define _PAGE_BIT_ACCESSED      8       /* software: page referenced */
  92 #define _PAGE_BIT_PROTNONE      9       /* software: if not present */
  93
  94 #define _PAGE_DIRTY             (1UL << _PAGE_BIT_DIRTY)
  95 #define _PAGE_PRESENT           (1UL << _PAGE_BIT_PRESENT)
  96 #define _PAGE_GLOBAL            (1UL << _PAGE_BIT_GLOBAL)
  97 #define _PAGE_LARGE             (1UL << _PAGE_BIT_LARGE)
  98 #define _PAGE_EXEC              (1UL << _PAGE_BIT_EXEC)
  99 #define _PAGE_WRITE             (1UL << _PAGE_BIT_WRITE)
 100 #define _PAGE_READ              (1UL << _PAGE_BIT_READ)
 101 #define _PAGE_NONCACHABLE       (1UL << _PAGE_BIT_NONCACHABLE)
 102 #define _PAGE_ACCESSED          (1UL << _PAGE_BIT_ACCESSED)
 103 #define _PAGE_PROTNONE          (1UL << _PAGE_BIT_PROTNONE)
 104
 105 #define _PAGE_TABLE     \
 106         ( _PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED \
 107         | _PAGE_DIRTY )
 108 #define _KERNPG_TABLE   \
 109         ( _PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED \
 110         | _PAGE_DIRTY )
 111 #define _PAGE_CHG_MASK  \
 112         ( PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY )
 113
 114 #ifdef CONFIG_MMU
 115 #define PAGE_NONE       \
 116         __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
 117 #define PAGE_SHARED     \
 118         __pgprot(_PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED)
 119 #define PAGE_SHARED_EXEC \
 120         __pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_WRITE | _PAGE_READ \
 121                 | _PAGE_ACCESSED)
 122 #define PAGE_COPY       \
 123         __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_ACCESSED)
 124 #define PAGE_COPY_EXEC  \
 125         __pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_ACCESSED)
 126 #define PAGE_READONLY   \
 127         __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_ACCESSED)
 128 #define PAGE_READONLY_EXEC \
 129         __pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_ACCESSED)
 130
 131 #define __PAGE_KERNEL   \
 132         ( _PAGE_PRESENT | _PAGE_EXEC | _PAGE_WRITE | _PAGE_READ | _PAGE_DIRTY \
 133         | _PAGE_ACCESSED )
 134 #define __PAGE_KERNEL_RO        ( __PAGE_KERNEL & ~_PAGE_WRITE )
 135 #define __PAGE_KERNEL_NOCACHE   ( __PAGE_KERNEL | _PAGE_NONCACHABLE)
 136
 137 #define MAKE_GLOBAL(x)  __pgprot((x) | _PAGE_GLOBAL)
 138
 139 #define PAGE_KERNEL             MAKE_GLOBAL(__PAGE_KERNEL)
 140 #define PAGE_KERNEL_RO          MAKE_GLOBAL(__PAGE_KERNEL_RO)
 141 #define PAGE_KERNEL_NOCACHE     MAKE_GLOBAL(__PAGE_KERNEL_NOCACHE)
 142
 143 #else
 144 #define PAGE_NONE               __pgprot(0)
 145 #define PAGE_SHARED             __pgprot(0)
 146 #define PAGE_SHARED_EXEC        __pgprot(0)
 147 #define PAGE_COPY               __pgprot(0)
 148 #define PAGE_COPY_EXEC          __pgprot(0)
 149 #define PAGE_READONLY           __pgprot(0)
 150 #define PAGE_READONLY_EXEC      __pgprot(0)
 151
 152 #define PAGE_KERNEL             __pgprot(0)
 153 #define PAGE_KERNEL_RO          __pgprot(0)
 154 #define PAGE_KERNEL_NOCACHE     __pgprot(0)
 155 #endif /* CONFIG_MMU */
 156
 157         /* xwr */
 158 #define __P000  PAGE_NONE
 159 #define __P001  PAGE_READONLY
 160 #define __P010  PAGE_COPY
 161 #define __P011  PAGE_COPY
 162 #define __P100  PAGE_READONLY_EXEC
 163 #define __P101  PAGE_READONLY_EXEC
 164 #define __P110  PAGE_COPY_EXEC
 165 #define __P111  PAGE_COPY_EXEC
 166
 167 #define __S000  PAGE_NONE
 168 #define __S001  PAGE_READONLY
 169 #define __S010  PAGE_SHARED
 170 #define __S011  PAGE_SHARED
 171 #define __S100  PAGE_READONLY_EXEC
 172 #define __S101  PAGE_READONLY_EXEC
 173 #define __S110  PAGE_SHARED_EXEC
 174 #define __S111  PAGE_SHARED_EXEC
 175
 176 /* page table for 0-4MB for everybody */
 177
 178 #define pte_present(x)  (pte_val(x) & (_PAGE_PRESENT | _PAGE_PROTNONE))
 179 #define pte_clear(mm,addr,xp)   do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
 180
 181 #define pmd_none(x)     (!pmd_val(x))
 182 #define pmd_present(x)  (pmd_val(x) & _PAGE_PRESENT)
 183 #define pmd_clear(xp)   do { set_pmd(xp, __pmd(0)); } while (0)
 184 #define pmd_bad(x)      ((pmd_val(x) & ~PAGE_MASK) != _KERNPG_TABLE)
 185
 186 #define pages_to_mb(x)  ((x) >> (20 - PAGE_SHIFT))
 187
 188 /*
 189  * The following only work if pte_present() is true.
 190  * Undefined behaviour if not..
 191  */
 192 static inline int pte_dirty(pte_t pte)
 193 {
 194         return pte_val(pte) & _PAGE_DIRTY;
 195 }
 196
 197 static inline int pte_young(pte_t pte)
 198 {
 199         return pte_val(pte) & _PAGE_ACCESSED;
 200 }
 201
 202 static inline int pte_write(pte_t pte)
 203 {
 204         return pte_val(pte) & _PAGE_WRITE;
 205 }
 206
 207 static inline int pte_special(pte_t pte)
 208 {
 209         return 0;
 210 }
 211
 212 static inline pte_t pte_mkclean(pte_t pte)
 213 {
 214         pte_val(pte) &= ~_PAGE_DIRTY;
 215         return pte;
 216 }
 217
 218 static inline pte_t pte_mkold(pte_t pte)
 219 {
 220         pte_val(pte) &= ~_PAGE_ACCESSED;
 221         return pte;
 222 }
 223
 224 static inline pte_t pte_wrprotect(pte_t pte)
 225 {
 226         pte_val(pte) &= ~_PAGE_WRITE;
 227         return pte;
 228 }
 229
 230 static inline pte_t pte_mkdirty(pte_t pte)
 231 {
 232         pte_val(pte) |= _PAGE_DIRTY;
 233         return pte;
 234 }
 235
 236 static inline pte_t pte_mkyoung(pte_t pte)
 237 {
 238         pte_val(pte) |= _PAGE_ACCESSED;
 239         return pte;
 240 }
 241
 242 static inline pte_t pte_mkwrite(pte_t pte)
 243 {
 244         pte_val(pte) |= _PAGE_WRITE;
 245         return pte;
 246 }
 247
 248 static inline pte_t pte_mkspecial(pte_t pte)
 249 {
 250         return pte;
 251 }
 252
 253 static inline  int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
 254 {
 255         return test_and_clear_bit(_PAGE_BIT_ACCESSED, ptep);
 256 }
 257
 258 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 259 {
 260         clear_bit(_PAGE_BIT_WRITE, ptep);
 261 }
 262
 263 /*
 264  * Macro and implementation to make a page protection as uncachable.
 265  */
 266 static inline pgprot_t pgprot_noncached(pgprot_t _prot)
 267 {
 268         unsigned long prot = pgprot_val(_prot);
 269
 270         prot |= _PAGE_NONCACHABLE;
 271         return __pgprot(prot);
 272 }
 273
 274 #define pgprot_writecombine(prot) pgprot_noncached(prot)
 275
 276 /*
 277  * Conversion functions: convert a page and protection to a page entry,
 278  * and a page entry and page directory to the page they refer to.
 279  */
 280 #define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), pgprot)
 281
 282 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 283 {
 284         set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) \
 285                 | pgprot_val(newprot)));
 286
 287         return pte;
 288 }
 289
 290 /*
 291  * Conversion functions: convert a page and protection to a page entry,
 292  * and a page entry and page directory to the page they refer to.
 293  */
 294
 295 static inline void pmd_set(pmd_t * pmdp, pte_t * ptep)
 296 {
 297         pmd_val(*pmdp) = (((unsigned long) ptep) & PAGE_MASK);
 298 }
 299
 300 #define pmd_page_vaddr(pmd)     \
 301         ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 302
 303 #ifndef CONFIG_DISCONTIGMEM
 304 #define pmd_page(pmd)   (mem_map + ((pmd_val(pmd) >> PAGE_SHIFT) - PFN_BASE))
 305 #endif /* !CONFIG_DISCONTIGMEM */
 306
 307 /* to find an entry in a page-table-directory. */
 308 #define pgd_index(address)      \
 309         (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
 310
 311 #define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
 312
 313 /* to find an entry in a kernel page-table-directory */
 314 #define pgd_offset_k(address)   pgd_offset(&init_mm, address)
 315
 316 #define pmd_index(address)      \
 317         (((address) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
 318
 319 #define pte_index(address)      \
 320         (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 321 #define pte_offset_kernel(dir, address) \
 322         ((pte_t *)pmd_page_vaddr(*(dir)) + pte_index(address))
 323 #define pte_offset_map(dir, address)    \
 324         ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
 325 #define pte_unmap(pte)          do { } while (0)
 326
 327 /* Encode and de-code a swap entry */
 328 #define __swp_type(x)                   (((x).val >> 2) & 0x1f)
 329 #define __swp_offset(x)                 ((x).val >> 10)
 330 #define __swp_entry(type, offset)       \
 331         ((swp_entry_t) { ((type) << 2) | ((offset) << 10) })
 332 #define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val(pte) })
 333 #define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 334
 335 #endif /* !__ASSEMBLY__ */
 336
 337 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
 338 #define kern_addr_valid(addr)   (1)
 339
 340 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
 341 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 342 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
 343 #define __HAVE_ARCH_PTE_SAME
 344 #include <asm-generic/pgtable.h>
 345
 346 #endif /* __KERNEL__ */
 347
 348 #endif /* _ASM_M32R_PGTABLE_H */