1 #ifndef __ASM_SH_PGTABLE_32_H 2 #define __ASM_SH_PGTABLE_32_H 3 4 /* 5 * Linux PTEL encoding. 6 * 7 * Hardware and software bit definitions for the PTEL value (see below for 8 * notes on SH-X2 MMUs and 64-bit PTEs): 9 * 10 * - Bits 0 and 7 are reserved on SH-3 (_PAGE_WT and _PAGE_SZ1 on SH-4). 11 * 12 * - Bit 1 is the SH-bit, but is unused on SH-3 due to an MMU bug (the 13 * hardware PTEL value can't have the SH-bit set when MMUCR.IX is set, 14 * which is the default in cpu-sh3/mmu_context.h:MMU_CONTROL_INIT). 15 * 16 * In order to keep this relatively clean, do not use these for defining 17 * SH-3 specific flags until all of the other unused bits have been 18 * exhausted. 19 * 20 * - Bit 9 is reserved by everyone and used by _PAGE_PROTNONE. 21 * 22 * - Bits 10 and 11 are low bits of the PPN that are reserved on >= 4K pages. 23 * Bit 10 is used for _PAGE_ACCESSED, bit 11 remains unused. 24 * 25 * - On 29 bit platforms, bits 31 to 29 are used for the space attributes 26 * and timing control which (together with bit 0) are moved into the 27 * old-style PTEA on the parts that support it. 28 * 29 * XXX: Leave the _PAGE_FILE and _PAGE_WT overhaul for a rainy day. 30 * 31 * SH-X2 MMUs and extended PTEs 32 * 33 * SH-X2 supports an extended mode TLB with split data arrays due to the 34 * number of bits needed for PR and SZ (now EPR and ESZ) encodings. The PR and 35 * SZ bit placeholders still exist in data array 1, but are implemented as 36 * reserved bits, with the real logic existing in data array 2. 37 * 38 * The downside to this is that we can no longer fit everything in to a 32-bit 39 * PTE encoding, so a 64-bit pte_t is necessary for these parts. On the plus 40 * side, this gives us quite a few spare bits to play with for future usage. 41 */ 42 /* Legacy and compat mode bits */ 43 #define _PAGE_WT 0x001 /* WT-bit on SH-4, 0 on SH-3 */ 44 #define _PAGE_HW_SHARED 0x002 /* SH-bit : shared among processes */ 45 #define _PAGE_DIRTY 0x004 /* D-bit : page changed */ 46 #define _PAGE_CACHABLE 0x008 /* C-bit : cachable */ 47 #define _PAGE_SZ0 0x010 /* SZ0-bit : Size of page */ 48 #define _PAGE_RW 0x020 /* PR0-bit : write access allowed */ 49 #define _PAGE_USER 0x040 /* PR1-bit : user space access allowed*/ 50 #define _PAGE_SZ1 0x080 /* SZ1-bit : Size of page (on SH-4) */ 51 #define _PAGE_PRESENT 0x100 /* V-bit : page is valid */ 52 #define _PAGE_PROTNONE 0x200 /* software: if not present */ 53 #define _PAGE_ACCESSED 0x400 /* software: page referenced */ 54 #define _PAGE_FILE _PAGE_WT /* software: pagecache or swap? */ 55 56 #define _PAGE_SZ_MASK (_PAGE_SZ0 | _PAGE_SZ1) 57 #define _PAGE_PR_MASK (_PAGE_RW | _PAGE_USER) 58 59 /* Extended mode bits */ 60 #define _PAGE_EXT_ESZ0 0x0010 /* ESZ0-bit: Size of page */ 61 #define _PAGE_EXT_ESZ1 0x0020 /* ESZ1-bit: Size of page */ 62 #define _PAGE_EXT_ESZ2 0x0040 /* ESZ2-bit: Size of page */ 63 #define _PAGE_EXT_ESZ3 0x0080 /* ESZ3-bit: Size of page */ 64 65 #define _PAGE_EXT_USER_EXEC 0x0100 /* EPR0-bit: User space executable */ 66 #define _PAGE_EXT_USER_WRITE 0x0200 /* EPR1-bit: User space writable */ 67 #define _PAGE_EXT_USER_READ 0x0400 /* EPR2-bit: User space readable */ 68 69 #define _PAGE_EXT_KERN_EXEC 0x0800 /* EPR3-bit: Kernel space executable */ 70 #define _PAGE_EXT_KERN_WRITE 0x1000 /* EPR4-bit: Kernel space writable */ 71 #define _PAGE_EXT_KERN_READ 0x2000 /* EPR5-bit: Kernel space readable */ 72 73 /* Wrapper for extended mode pgprot twiddling */ 74 #define _PAGE_EXT(x) ((unsigned long long)(x) << 32) 75 76 /* software: moves to PTEA.TC (Timing Control) */ 77 #define _PAGE_PCC_AREA5 0x00000000 /* use BSC registers for area5 */ 78 #define _PAGE_PCC_AREA6 0x80000000 /* use BSC registers for area6 */ 79 80 /* software: moves to PTEA.SA[2:0] (Space Attributes) */ 81 #define _PAGE_PCC_IODYN 0x00000001 /* IO space, dynamically sized bus */ 82 #define _PAGE_PCC_IO8 0x20000000 /* IO space, 8 bit bus */ 83 #define _PAGE_PCC_IO16 0x20000001 /* IO space, 16 bit bus */ 84 #define _PAGE_PCC_COM8 0x40000000 /* Common Memory space, 8 bit bus */ 85 #define _PAGE_PCC_COM16 0x40000001 /* Common Memory space, 16 bit bus */ 86 #define _PAGE_PCC_ATR8 0x60000000 /* Attribute Memory space, 8 bit bus */ 87 #define _PAGE_PCC_ATR16 0x60000001 /* Attribute Memory space, 6 bit bus */ 88 89 /* Mask which drops unused bits from the PTEL value */ 90 #if defined(CONFIG_CPU_SH3) 91 #define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED| \ 92 _PAGE_FILE | _PAGE_SZ1 | \ 93 _PAGE_HW_SHARED) 94 #elif defined(CONFIG_X2TLB) 95 /* Get rid of the legacy PR/SZ bits when using extended mode */ 96 #define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED | \ 97 _PAGE_FILE | _PAGE_PR_MASK | _PAGE_SZ_MASK) 98 #else 99 #define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED | _PAGE_FILE) 100 #endif 101 102 #define _PAGE_FLAGS_HARDWARE_MASK (PHYS_ADDR_MASK & ~(_PAGE_CLEAR_FLAGS)) 103 104 /* Hardware flags, page size encoding */ 105 #if !defined(CONFIG_MMU) 106 # define _PAGE_FLAGS_HARD 0ULL 107 #elif defined(CONFIG_X2TLB) 108 # if defined(CONFIG_PAGE_SIZE_4KB) 109 # define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ0) 110 # elif defined(CONFIG_PAGE_SIZE_8KB) 111 # define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ1) 112 # elif defined(CONFIG_PAGE_SIZE_64KB) 113 # define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ2) 114 # endif 115 #else 116 # if defined(CONFIG_PAGE_SIZE_4KB) 117 # define _PAGE_FLAGS_HARD _PAGE_SZ0 118 # elif defined(CONFIG_PAGE_SIZE_64KB) 119 # define _PAGE_FLAGS_HARD _PAGE_SZ1 120 # endif 121 #endif 122 123 #if defined(CONFIG_X2TLB) 124 # if defined(CONFIG_HUGETLB_PAGE_SIZE_64K) 125 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ2) 126 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_256K) 127 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ2) 128 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB) 129 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ1 | _PAGE_EXT_ESZ2) 130 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_4MB) 131 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ3) 132 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_64MB) 133 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ2 | _PAGE_EXT_ESZ3) 134 # endif 135 #else 136 # if defined(CONFIG_HUGETLB_PAGE_SIZE_64K) 137 # define _PAGE_SZHUGE (_PAGE_SZ1) 138 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB) 139 # define _PAGE_SZHUGE (_PAGE_SZ0 | _PAGE_SZ1) 140 # endif 141 #endif 142 143 /* 144 * Stub out _PAGE_SZHUGE if we don't have a good definition for it, 145 * to make pte_mkhuge() happy. 146 */ 147 #ifndef _PAGE_SZHUGE 148 # define _PAGE_SZHUGE (_PAGE_FLAGS_HARD) 149 #endif 150 151 #define _PAGE_CHG_MASK \ 152 (PTE_MASK | _PAGE_ACCESSED | _PAGE_CACHABLE | _PAGE_DIRTY) 153 154 #ifndef __ASSEMBLY__ 155 156 #if defined(CONFIG_X2TLB) /* SH-X2 TLB */ 157 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \ 158 _PAGE_ACCESSED | _PAGE_FLAGS_HARD) 159 160 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \ 161 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \ 162 _PAGE_EXT(_PAGE_EXT_KERN_READ | \ 163 _PAGE_EXT_KERN_WRITE | \ 164 _PAGE_EXT_USER_READ | \ 165 _PAGE_EXT_USER_WRITE)) 166 167 #define PAGE_EXECREAD __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \ 168 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \ 169 _PAGE_EXT(_PAGE_EXT_KERN_EXEC | \ 170 _PAGE_EXT_KERN_READ | \ 171 _PAGE_EXT_USER_EXEC | \ 172 _PAGE_EXT_USER_READ)) 173 174 #define PAGE_COPY PAGE_EXECREAD 175 176 #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \ 177 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \ 178 _PAGE_EXT(_PAGE_EXT_KERN_READ | \ 179 _PAGE_EXT_USER_READ)) 180 181 #define PAGE_WRITEONLY __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \ 182 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \ 183 _PAGE_EXT(_PAGE_EXT_KERN_WRITE | \ 184 _PAGE_EXT_USER_WRITE)) 185 186 #define PAGE_RWX __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \ 187 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \ 188 _PAGE_EXT(_PAGE_EXT_KERN_WRITE | \ 189 _PAGE_EXT_KERN_READ | \ 190 _PAGE_EXT_KERN_EXEC | \ 191 _PAGE_EXT_USER_WRITE | \ 192 _PAGE_EXT_USER_READ | \ 193 _PAGE_EXT_USER_EXEC)) 194 195 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \ 196 _PAGE_DIRTY | _PAGE_ACCESSED | \ 197 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \ 198 _PAGE_EXT(_PAGE_EXT_KERN_READ | \ 199 _PAGE_EXT_KERN_WRITE | \ 200 _PAGE_EXT_KERN_EXEC)) 201 202 #define PAGE_KERNEL_NOCACHE \ 203 __pgprot(_PAGE_PRESENT | _PAGE_DIRTY | \ 204 _PAGE_ACCESSED | _PAGE_HW_SHARED | \ 205 _PAGE_FLAGS_HARD | \ 206 _PAGE_EXT(_PAGE_EXT_KERN_READ | \ 207 _PAGE_EXT_KERN_WRITE | \ 208 _PAGE_EXT_KERN_EXEC)) 209 210 #define PAGE_KERNEL_RO __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \ 211 _PAGE_DIRTY | _PAGE_ACCESSED | \ 212 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \ 213 _PAGE_EXT(_PAGE_EXT_KERN_READ | \ 214 _PAGE_EXT_KERN_EXEC)) 215 216 #define PAGE_KERNEL_PCC(slot, type) \ 217 __pgprot(_PAGE_PRESENT | _PAGE_DIRTY | \ 218 _PAGE_ACCESSED | _PAGE_FLAGS_HARD | \ 219 _PAGE_EXT(_PAGE_EXT_KERN_READ | \ 220 _PAGE_EXT_KERN_WRITE | \ 221 _PAGE_EXT_KERN_EXEC) \ 222 (slot ? _PAGE_PCC_AREA5 : _PAGE_PCC_AREA6) | \ 223 (type)) 224 225 #elif defined(CONFIG_MMU) /* SH-X TLB */ 226 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \ 227 _PAGE_ACCESSED | _PAGE_FLAGS_HARD) 228 229 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \ 230 _PAGE_CACHABLE | _PAGE_ACCESSED | \ 231 _PAGE_FLAGS_HARD) 232 233 #define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \ 234 _PAGE_ACCESSED | _PAGE_FLAGS_HARD) 235 236 #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \ 237 _PAGE_ACCESSED | _PAGE_FLAGS_HARD) 238 239 #define PAGE_EXECREAD PAGE_READONLY 240 #define PAGE_RWX PAGE_SHARED 241 #define PAGE_WRITEONLY PAGE_SHARED 242 243 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_CACHABLE | \ 244 _PAGE_DIRTY | _PAGE_ACCESSED | \ 245 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD) 246 247 #define PAGE_KERNEL_NOCACHE \ 248 __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \ 249 _PAGE_ACCESSED | _PAGE_HW_SHARED | \ 250 _PAGE_FLAGS_HARD) 251 252 #define PAGE_KERNEL_RO __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \ 253 _PAGE_DIRTY | _PAGE_ACCESSED | \ 254 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD) 255 256 #define PAGE_KERNEL_PCC(slot, type) \ 257 __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \ 258 _PAGE_ACCESSED | _PAGE_FLAGS_HARD | \ 259 (slot ? _PAGE_PCC_AREA5 : _PAGE_PCC_AREA6) | \ 260 (type)) 261 #else /* no mmu */ 262 #define PAGE_NONE __pgprot(0) 263 #define PAGE_SHARED __pgprot(0) 264 #define PAGE_COPY __pgprot(0) 265 #define PAGE_EXECREAD __pgprot(0) 266 #define PAGE_RWX __pgprot(0) 267 #define PAGE_READONLY __pgprot(0) 268 #define PAGE_WRITEONLY __pgprot(0) 269 #define PAGE_KERNEL __pgprot(0) 270 #define PAGE_KERNEL_NOCACHE __pgprot(0) 271 #define PAGE_KERNEL_RO __pgprot(0) 272 273 #define PAGE_KERNEL_PCC(slot, type) \ 274 __pgprot(0) 275 #endif 276 277 #endif /* __ASSEMBLY__ */ 278 279 #ifndef __ASSEMBLY__ 280 281 /* 282 * Certain architectures need to do special things when PTEs 283 * within a page table are directly modified. Thus, the following 284 * hook is made available. 285 */ 286 #ifdef CONFIG_X2TLB 287 static inline void set_pte(pte_t *ptep, pte_t pte) 288 { 289 ptep->pte_high = pte.pte_high; 290 smp_wmb(); 291 ptep->pte_low = pte.pte_low; 292 } 293 #else 294 #define set_pte(pteptr, pteval) (*(pteptr) = pteval) 295 #endif 296 297 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval) 298 299 /* 300 * (pmds are folded into pgds so this doesn't get actually called, 301 * but the define is needed for a generic inline function.) 302 */ 303 #define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval) 304 305 #define pfn_pte(pfn, prot) \ 306 __pte(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) 307 #define pfn_pmd(pfn, prot) \ 308 __pmd(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) 309 310 #define pte_none(x) (!pte_val(x)) 311 #define pte_present(x) ((x).pte_low & (_PAGE_PRESENT | _PAGE_PROTNONE)) 312 313 #define pte_clear(mm,addr,xp) do { set_pte_at(mm, addr, xp, __pte(0)); } while (0) 314 315 #define pmd_none(x) (!pmd_val(x)) 316 #define pmd_present(x) (pmd_val(x)) 317 #define pmd_clear(xp) do { set_pmd(xp, __pmd(0)); } while (0) 318 #define pmd_bad(x) (pmd_val(x) & ~PAGE_MASK) 319 320 #define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT)) 321 #define pte_page(x) pfn_to_page(pte_pfn(x)) 322 323 /* 324 * The following only work if pte_present() is true. 325 * Undefined behaviour if not.. 326 */ 327 #define pte_not_present(pte) (!((pte).pte_low & _PAGE_PRESENT)) 328 #define pte_dirty(pte) ((pte).pte_low & _PAGE_DIRTY) 329 #define pte_young(pte) ((pte).pte_low & _PAGE_ACCESSED) 330 #define pte_file(pte) ((pte).pte_low & _PAGE_FILE) 331 #define pte_special(pte) (0) 332 333 #ifdef CONFIG_X2TLB 334 #define pte_write(pte) ((pte).pte_high & _PAGE_EXT_USER_WRITE) 335 #else 336 #define pte_write(pte) ((pte).pte_low & _PAGE_RW) 337 #endif 338 339 #define PTE_BIT_FUNC(h,fn,op) \ 340 static inline pte_t pte_##fn(pte_t pte) { pte.pte_##h op; return pte; } 341 342 #ifdef CONFIG_X2TLB 343 /* 344 * We cheat a bit in the SH-X2 TLB case. As the permission bits are 345 * individually toggled (and user permissions are entirely decoupled from 346 * kernel permissions), we attempt to couple them a bit more sanely here. 347 */ 348 PTE_BIT_FUNC(high, wrprotect, &= ~_PAGE_EXT_USER_WRITE); 349 PTE_BIT_FUNC(high, mkwrite, |= _PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE); 350 PTE_BIT_FUNC(high, mkhuge, |= _PAGE_SZHUGE); 351 #else 352 PTE_BIT_FUNC(low, wrprotect, &= ~_PAGE_RW); 353 PTE_BIT_FUNC(low, mkwrite, |= _PAGE_RW); 354 PTE_BIT_FUNC(low, mkhuge, |= _PAGE_SZHUGE); 355 #endif 356 357 PTE_BIT_FUNC(low, mkclean, &= ~_PAGE_DIRTY); 358 PTE_BIT_FUNC(low, mkdirty, |= _PAGE_DIRTY); 359 PTE_BIT_FUNC(low, mkold, &= ~_PAGE_ACCESSED); 360 PTE_BIT_FUNC(low, mkyoung, |= _PAGE_ACCESSED); 361 362 static inline pte_t pte_mkspecial(pte_t pte) { return pte; } 363 364 /* 365 * Macro and implementation to make a page protection as uncachable. 366 */ 367 #define pgprot_writecombine(prot) \ 368 __pgprot(pgprot_val(prot) & ~_PAGE_CACHABLE) 369 370 #define pgprot_noncached pgprot_writecombine 371 372 /* 373 * Conversion functions: convert a page and protection to a page entry, 374 * and a page entry and page directory to the page they refer to. 375 * 376 * extern pte_t mk_pte(struct page *page, pgprot_t pgprot) 377 */ 378 #define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot)) 379 380 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 381 { 382 pte.pte_low &= _PAGE_CHG_MASK; 383 pte.pte_low |= pgprot_val(newprot); 384 385 #ifdef CONFIG_X2TLB 386 pte.pte_high |= pgprot_val(newprot) >> 32; 387 #endif 388 389 return pte; 390 } 391 392 #define pmd_page_vaddr(pmd) ((unsigned long)pmd_val(pmd)) 393 #define pmd_page(pmd) (virt_to_page(pmd_val(pmd))) 394 395 /* to find an entry in a page-table-directory. */ 396 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1)) 397 #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address)) 398 399 /* to find an entry in a kernel page-table-directory */ 400 #define pgd_offset_k(address) pgd_offset(&init_mm, address) 401 402 /* Find an entry in the third-level page table.. */ 403 #define pte_index(address) ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) 404 #define pte_offset_kernel(dir, address) \ 405 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address)) 406 #define pte_offset_map(dir, address) pte_offset_kernel(dir, address) 407 #define pte_offset_map_nested(dir, address) pte_offset_kernel(dir, address) 408 409 #define pte_unmap(pte) do { } while (0) 410 #define pte_unmap_nested(pte) do { } while (0) 411 412 #ifdef CONFIG_X2TLB 413 #define pte_ERROR(e) \ 414 printk("%s:%d: bad pte %p(%08lx%08lx).\n", __FILE__, __LINE__, \ 415 &(e), (e).pte_high, (e).pte_low) 416 #define pgd_ERROR(e) \ 417 printk("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e)) 418 #else 419 #define pte_ERROR(e) \ 420 printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e)) 421 #define pgd_ERROR(e) \ 422 printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e)) 423 #endif 424 425 /* 426 * Encode and de-code a swap entry 427 * 428 * Constraints: 429 * _PAGE_FILE at bit 0 430 * _PAGE_PRESENT at bit 8 431 * _PAGE_PROTNONE at bit 9 432 * 433 * For the normal case, we encode the swap type into bits 0:7 and the 434 * swap offset into bits 10:30. For the 64-bit PTE case, we keep the 435 * preserved bits in the low 32-bits and use the upper 32 as the swap 436 * offset (along with a 5-bit type), following the same approach as x86 437 * PAE. This keeps the logic quite simple, and allows for a full 32 438 * PTE_FILE_MAX_BITS, as opposed to the 29-bits we're constrained with 439 * in the pte_low case. 440 * 441 * As is evident by the Alpha code, if we ever get a 64-bit unsigned 442 * long (swp_entry_t) to match up with the 64-bit PTEs, this all becomes 443 * much cleaner.. 444 * 445 * NOTE: We should set ZEROs at the position of _PAGE_PRESENT 446 * and _PAGE_PROTNONE bits 447 */ 448 #ifdef CONFIG_X2TLB 449 #define __swp_type(x) ((x).val & 0x1f) 450 #define __swp_offset(x) ((x).val >> 5) 451 #define __swp_entry(type, offset) ((swp_entry_t){ (type) | (offset) << 5}) 452 #define __pte_to_swp_entry(pte) ((swp_entry_t){ (pte).pte_high }) 453 #define __swp_entry_to_pte(x) ((pte_t){ 0, (x).val }) 454 455 /* 456 * Encode and decode a nonlinear file mapping entry 457 */ 458 #define pte_to_pgoff(pte) ((pte).pte_high) 459 #define pgoff_to_pte(off) ((pte_t) { _PAGE_FILE, (off) }) 460 461 #define PTE_FILE_MAX_BITS 32 462 #else 463 #define __swp_type(x) ((x).val & 0xff) 464 #define __swp_offset(x) ((x).val >> 10) 465 #define __swp_entry(type, offset) ((swp_entry_t){(type) | (offset) <<10}) 466 467 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 1 }) 468 #define __swp_entry_to_pte(x) ((pte_t) { (x).val << 1 }) 469 470 /* 471 * Encode and decode a nonlinear file mapping entry 472 */ 473 #define PTE_FILE_MAX_BITS 29 474 #define pte_to_pgoff(pte) (pte_val(pte) >> 1) 475 #define pgoff_to_pte(off) ((pte_t) { ((off) << 1) | _PAGE_FILE }) 476 #endif 477 478 #endif /* __ASSEMBLY__ */ 479 #endif /* __ASM_SH_PGTABLE_32_H */ 480