arch/m32r/include/asm/pgtable.h

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