1 #ifndef _ASM_IA64_PGTABLE_H 2 #define _ASM_IA64_PGTABLE_H 3 4 /* 5 * This file contains the functions and defines necessary to modify and use 6 * the IA-64 page table tree. 7 * 8 * This hopefully works with any (fixed) IA-64 page-size, as defined 9 * in <asm/page.h>. 10 * 11 * Copyright (C) 1998-2005 Hewlett-Packard Co 12 * David Mosberger-Tang <davidm@hpl.hp.com> 13 */ 14 15 16 #include <asm/mman.h> 17 #include <asm/page.h> 18 #include <asm/processor.h> 19 #include <asm/types.h> 20 21 #define IA64_MAX_PHYS_BITS 50 /* max. number of physical address bits (architected) */ 22 23 /* 24 * First, define the various bits in a PTE. Note that the PTE format 25 * matches the VHPT short format, the firt doubleword of the VHPD long 26 * format, and the first doubleword of the TLB insertion format. 27 */ 28 #define _PAGE_P_BIT 0 29 #define _PAGE_A_BIT 5 30 #define _PAGE_D_BIT 6 31 32 #define _PAGE_P (1 << _PAGE_P_BIT) /* page present bit */ 33 #define _PAGE_MA_WB (0x0 << 2) /* write back memory attribute */ 34 #define _PAGE_MA_UC (0x4 << 2) /* uncacheable memory attribute */ 35 #define _PAGE_MA_UCE (0x5 << 2) /* UC exported attribute */ 36 #define _PAGE_MA_WC (0x6 << 2) /* write coalescing memory attribute */ 37 #define _PAGE_MA_NAT (0x7 << 2) /* not-a-thing attribute */ 38 #define _PAGE_MA_MASK (0x7 << 2) 39 #define _PAGE_PL_0 (0 << 7) /* privilege level 0 (kernel) */ 40 #define _PAGE_PL_1 (1 << 7) /* privilege level 1 (unused) */ 41 #define _PAGE_PL_2 (2 << 7) /* privilege level 2 (unused) */ 42 #define _PAGE_PL_3 (3 << 7) /* privilege level 3 (user) */ 43 #define _PAGE_PL_MASK (3 << 7) 44 #define _PAGE_AR_R (0 << 9) /* read only */ 45 #define _PAGE_AR_RX (1 << 9) /* read & execute */ 46 #define _PAGE_AR_RW (2 << 9) /* read & write */ 47 #define _PAGE_AR_RWX (3 << 9) /* read, write & execute */ 48 #define _PAGE_AR_R_RW (4 << 9) /* read / read & write */ 49 #define _PAGE_AR_RX_RWX (5 << 9) /* read & exec / read, write & exec */ 50 #define _PAGE_AR_RWX_RW (6 << 9) /* read, write & exec / read & write */ 51 #define _PAGE_AR_X_RX (7 << 9) /* exec & promote / read & exec */ 52 #define _PAGE_AR_MASK (7 << 9) 53 #define _PAGE_AR_SHIFT 9 54 #define _PAGE_A (1 << _PAGE_A_BIT) /* page accessed bit */ 55 #define _PAGE_D (1 << _PAGE_D_BIT) /* page dirty bit */ 56 #define _PAGE_PPN_MASK (((__IA64_UL(1) << IA64_MAX_PHYS_BITS) - 1) & ~0xfffUL) 57 #define _PAGE_ED (__IA64_UL(1) << 52) /* exception deferral */ 58 #define _PAGE_PROTNONE (__IA64_UL(1) << 63) 59 60 #define _PFN_MASK _PAGE_PPN_MASK 61 /* Mask of bits which may be changed by pte_modify(); the odd bits are there for _PAGE_PROTNONE */ 62 #define _PAGE_CHG_MASK (_PAGE_P | _PAGE_PROTNONE | _PAGE_PL_MASK | _PAGE_AR_MASK | _PAGE_ED) 63 64 #define _PAGE_SIZE_4K 12 65 #define _PAGE_SIZE_8K 13 66 #define _PAGE_SIZE_16K 14 67 #define _PAGE_SIZE_64K 16 68 #define _PAGE_SIZE_256K 18 69 #define _PAGE_SIZE_1M 20 70 #define _PAGE_SIZE_4M 22 71 #define _PAGE_SIZE_16M 24 72 #define _PAGE_SIZE_64M 26 73 #define _PAGE_SIZE_256M 28 74 #define _PAGE_SIZE_1G 30 75 #define _PAGE_SIZE_4G 32 76 77 #define __ACCESS_BITS _PAGE_ED | _PAGE_A | _PAGE_P | _PAGE_MA_WB 78 #define __DIRTY_BITS_NO_ED _PAGE_A | _PAGE_P | _PAGE_D | _PAGE_MA_WB 79 #define __DIRTY_BITS _PAGE_ED | __DIRTY_BITS_NO_ED 80 81 /* 82 * How many pointers will a page table level hold expressed in shift 83 */ 84 #define PTRS_PER_PTD_SHIFT (PAGE_SHIFT-3) 85 86 /* 87 * Definitions for fourth level: 88 */ 89 #define PTRS_PER_PTE (__IA64_UL(1) << (PTRS_PER_PTD_SHIFT)) 90 91 /* 92 * Definitions for third level: 93 * 94 * PMD_SHIFT determines the size of the area a third-level page table 95 * can map. 96 */ 97 #define PMD_SHIFT (PAGE_SHIFT + (PTRS_PER_PTD_SHIFT)) 98 #define PMD_SIZE (1UL << PMD_SHIFT) 99 #define PMD_MASK (~(PMD_SIZE-1)) 100 #define PTRS_PER_PMD (1UL << (PTRS_PER_PTD_SHIFT)) 101 102 #if CONFIG_PGTABLE_LEVELS == 4 103 /* 104 * Definitions for second level: 105 * 106 * PUD_SHIFT determines the size of the area a second-level page table 107 * can map. 108 */ 109 #define PUD_SHIFT (PMD_SHIFT + (PTRS_PER_PTD_SHIFT)) 110 #define PUD_SIZE (1UL << PUD_SHIFT) 111 #define PUD_MASK (~(PUD_SIZE-1)) 112 #define PTRS_PER_PUD (1UL << (PTRS_PER_PTD_SHIFT)) 113 #endif 114 115 /* 116 * Definitions for first level: 117 * 118 * PGDIR_SHIFT determines what a first-level page table entry can map. 119 */ 120 #if CONFIG_PGTABLE_LEVELS == 4 121 #define PGDIR_SHIFT (PUD_SHIFT + (PTRS_PER_PTD_SHIFT)) 122 #else 123 #define PGDIR_SHIFT (PMD_SHIFT + (PTRS_PER_PTD_SHIFT)) 124 #endif 125 #define PGDIR_SIZE (__IA64_UL(1) << PGDIR_SHIFT) 126 #define PGDIR_MASK (~(PGDIR_SIZE-1)) 127 #define PTRS_PER_PGD_SHIFT PTRS_PER_PTD_SHIFT 128 #define PTRS_PER_PGD (1UL << PTRS_PER_PGD_SHIFT) 129 #define USER_PTRS_PER_PGD (5*PTRS_PER_PGD/8) /* regions 0-4 are user regions */ 130 #define FIRST_USER_ADDRESS 0UL 131 132 /* 133 * All the normal masks have the "page accessed" bits on, as any time 134 * they are used, the page is accessed. They are cleared only by the 135 * page-out routines. 136 */ 137 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_A) 138 #define PAGE_SHARED __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RW) 139 #define PAGE_READONLY __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_R) 140 #define PAGE_COPY __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_R) 141 #define PAGE_COPY_EXEC __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX) 142 #define PAGE_GATE __pgprot(__ACCESS_BITS | _PAGE_PL_0 | _PAGE_AR_X_RX) 143 #define PAGE_KERNEL __pgprot(__DIRTY_BITS | _PAGE_PL_0 | _PAGE_AR_RWX) 144 #define PAGE_KERNELRX __pgprot(__ACCESS_BITS | _PAGE_PL_0 | _PAGE_AR_RX) 145 #define PAGE_KERNEL_UC __pgprot(__DIRTY_BITS | _PAGE_PL_0 | _PAGE_AR_RWX | \ 146 _PAGE_MA_UC) 147 148 # ifndef __ASSEMBLY__ 149 150 #include <linux/sched.h> /* for mm_struct */ 151 #include <linux/bitops.h> 152 #include <asm/cacheflush.h> 153 #include <asm/mmu_context.h> 154 155 /* 156 * Next come the mappings that determine how mmap() protection bits 157 * (PROT_EXEC, PROT_READ, PROT_WRITE, PROT_NONE) get implemented. The 158 * _P version gets used for a private shared memory segment, the _S 159 * version gets used for a shared memory segment with MAP_SHARED on. 160 * In a private shared memory segment, we do a copy-on-write if a task 161 * attempts to write to the page. 162 */ 163 /* xwr */ 164 #define __P000 PAGE_NONE 165 #define __P001 PAGE_READONLY 166 #define __P010 PAGE_READONLY /* write to priv pg -> copy & make writable */ 167 #define __P011 PAGE_READONLY /* ditto */ 168 #define __P100 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX) 169 #define __P101 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX) 170 #define __P110 PAGE_COPY_EXEC 171 #define __P111 PAGE_COPY_EXEC 172 173 #define __S000 PAGE_NONE 174 #define __S001 PAGE_READONLY 175 #define __S010 PAGE_SHARED /* we don't have (and don't need) write-only */ 176 #define __S011 PAGE_SHARED 177 #define __S100 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX) 178 #define __S101 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX) 179 #define __S110 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX) 180 #define __S111 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX) 181 182 #define pgd_ERROR(e) printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e)) 183 #if CONFIG_PGTABLE_LEVELS == 4 184 #define pud_ERROR(e) printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e)) 185 #endif 186 #define pmd_ERROR(e) printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e)) 187 #define pte_ERROR(e) printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e)) 188 189 190 /* 191 * Some definitions to translate between mem_map, PTEs, and page addresses: 192 */ 193 194 195 /* Quick test to see if ADDR is a (potentially) valid physical address. */ 196 static inline long 197 ia64_phys_addr_valid (unsigned long addr) 198 { 199 return (addr & (local_cpu_data->unimpl_pa_mask)) == 0; 200 } 201 202 /* 203 * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel 204 * memory. For the return value to be meaningful, ADDR must be >= 205 * PAGE_OFFSET. This operation can be relatively expensive (e.g., 206 * require a hash-, or multi-level tree-lookup or something of that 207 * sort) but it guarantees to return TRUE only if accessing the page 208 * at that address does not cause an error. Note that there may be 209 * addresses for which kern_addr_valid() returns FALSE even though an 210 * access would not cause an error (e.g., this is typically true for 211 * memory mapped I/O regions. 212 * 213 * XXX Need to implement this for IA-64. 214 */ 215 #define kern_addr_valid(addr) (1) 216 217 218 /* 219 * Now come the defines and routines to manage and access the three-level 220 * page table. 221 */ 222 223 224 #define VMALLOC_START (RGN_BASE(RGN_GATE) + 0x200000000UL) 225 #ifdef CONFIG_VIRTUAL_MEM_MAP 226 # define VMALLOC_END_INIT (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9))) 227 extern unsigned long VMALLOC_END; 228 #else 229 #if defined(CONFIG_SPARSEMEM) && defined(CONFIG_SPARSEMEM_VMEMMAP) 230 /* SPARSEMEM_VMEMMAP uses half of vmalloc... */ 231 # define VMALLOC_END (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 10))) 232 # define vmemmap ((struct page *)VMALLOC_END) 233 #else 234 # define VMALLOC_END (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9))) 235 #endif 236 #endif 237 238 /* fs/proc/kcore.c */ 239 #define kc_vaddr_to_offset(v) ((v) - RGN_BASE(RGN_GATE)) 240 #define kc_offset_to_vaddr(o) ((o) + RGN_BASE(RGN_GATE)) 241 242 #define RGN_MAP_SHIFT (PGDIR_SHIFT + PTRS_PER_PGD_SHIFT - 3) 243 #define RGN_MAP_LIMIT ((1UL << RGN_MAP_SHIFT) - PAGE_SIZE) /* per region addr limit */ 244 245 /* 246 * Conversion functions: convert page frame number (pfn) and a protection value to a page 247 * table entry (pte). 248 */ 249 #define pfn_pte(pfn, pgprot) \ 250 ({ pte_t __pte; pte_val(__pte) = ((pfn) << PAGE_SHIFT) | pgprot_val(pgprot); __pte; }) 251 252 /* Extract pfn from pte. */ 253 #define pte_pfn(_pte) ((pte_val(_pte) & _PFN_MASK) >> PAGE_SHIFT) 254 255 #define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot)) 256 257 /* This takes a physical page address that is used by the remapping functions */ 258 #define mk_pte_phys(physpage, pgprot) \ 259 ({ pte_t __pte; pte_val(__pte) = physpage + pgprot_val(pgprot); __pte; }) 260 261 #define pte_modify(_pte, newprot) \ 262 (__pte((pte_val(_pte) & ~_PAGE_CHG_MASK) | (pgprot_val(newprot) & _PAGE_CHG_MASK))) 263 264 #define pte_none(pte) (!pte_val(pte)) 265 #define pte_present(pte) (pte_val(pte) & (_PAGE_P | _PAGE_PROTNONE)) 266 #define pte_clear(mm,addr,pte) (pte_val(*(pte)) = 0UL) 267 /* pte_page() returns the "struct page *" corresponding to the PTE: */ 268 #define pte_page(pte) virt_to_page(((pte_val(pte) & _PFN_MASK) + PAGE_OFFSET)) 269 270 #define pmd_none(pmd) (!pmd_val(pmd)) 271 #define pmd_bad(pmd) (!ia64_phys_addr_valid(pmd_val(pmd))) 272 #define pmd_present(pmd) (pmd_val(pmd) != 0UL) 273 #define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0UL) 274 #define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & _PFN_MASK)) 275 #define pmd_page(pmd) virt_to_page((pmd_val(pmd) + PAGE_OFFSET)) 276 277 #define pud_none(pud) (!pud_val(pud)) 278 #define pud_bad(pud) (!ia64_phys_addr_valid(pud_val(pud))) 279 #define pud_present(pud) (pud_val(pud) != 0UL) 280 #define pud_clear(pudp) (pud_val(*(pudp)) = 0UL) 281 #define pud_page_vaddr(pud) ((unsigned long) __va(pud_val(pud) & _PFN_MASK)) 282 #define pud_page(pud) virt_to_page((pud_val(pud) + PAGE_OFFSET)) 283 284 #if CONFIG_PGTABLE_LEVELS == 4 285 #define pgd_none(pgd) (!pgd_val(pgd)) 286 #define pgd_bad(pgd) (!ia64_phys_addr_valid(pgd_val(pgd))) 287 #define pgd_present(pgd) (pgd_val(pgd) != 0UL) 288 #define pgd_clear(pgdp) (pgd_val(*(pgdp)) = 0UL) 289 #define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_val(pgd) & _PFN_MASK)) 290 #define pgd_page(pgd) virt_to_page((pgd_val(pgd) + PAGE_OFFSET)) 291 #endif 292 293 /* 294 * The following have defined behavior only work if pte_present() is true. 295 */ 296 #define pte_write(pte) ((unsigned) (((pte_val(pte) & _PAGE_AR_MASK) >> _PAGE_AR_SHIFT) - 2) <= 4) 297 #define pte_exec(pte) ((pte_val(pte) & _PAGE_AR_RX) != 0) 298 #define pte_dirty(pte) ((pte_val(pte) & _PAGE_D) != 0) 299 #define pte_young(pte) ((pte_val(pte) & _PAGE_A) != 0) 300 #define pte_special(pte) 0 301 302 /* 303 * Note: we convert AR_RWX to AR_RX and AR_RW to AR_R by clearing the 2nd bit in the 304 * access rights: 305 */ 306 #define pte_wrprotect(pte) (__pte(pte_val(pte) & ~_PAGE_AR_RW)) 307 #define pte_mkwrite(pte) (__pte(pte_val(pte) | _PAGE_AR_RW)) 308 #define pte_mkold(pte) (__pte(pte_val(pte) & ~_PAGE_A)) 309 #define pte_mkyoung(pte) (__pte(pte_val(pte) | _PAGE_A)) 310 #define pte_mkclean(pte) (__pte(pte_val(pte) & ~_PAGE_D)) 311 #define pte_mkdirty(pte) (__pte(pte_val(pte) | _PAGE_D)) 312 #define pte_mkhuge(pte) (__pte(pte_val(pte))) 313 #define pte_mkspecial(pte) (pte) 314 315 /* 316 * Because ia64's Icache and Dcache is not coherent (on a cpu), we need to 317 * sync icache and dcache when we insert *new* executable page. 318 * __ia64_sync_icache_dcache() check Pg_arch_1 bit and flush icache 319 * if necessary. 320 * 321 * set_pte() is also called by the kernel, but we can expect that the kernel 322 * flushes icache explicitly if necessary. 323 */ 324 #define pte_present_exec_user(pte)\ 325 ((pte_val(pte) & (_PAGE_P | _PAGE_PL_MASK | _PAGE_AR_RX)) == \ 326 (_PAGE_P | _PAGE_PL_3 | _PAGE_AR_RX)) 327 328 extern void __ia64_sync_icache_dcache(pte_t pteval); 329 static inline void set_pte(pte_t *ptep, pte_t pteval) 330 { 331 /* page is present && page is user && page is executable 332 * && (page swapin or new page or page migraton 333 * || copy_on_write with page copying.) 334 */ 335 if (pte_present_exec_user(pteval) && 336 (!pte_present(*ptep) || 337 pte_pfn(*ptep) != pte_pfn(pteval))) 338 /* load_module() calles flush_icache_range() explicitly*/ 339 __ia64_sync_icache_dcache(pteval); 340 *ptep = pteval; 341 } 342 343 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval) 344 345 /* 346 * Make page protection values cacheable, uncacheable, or write- 347 * combining. Note that "protection" is really a misnomer here as the 348 * protection value contains the memory attribute bits, dirty bits, and 349 * various other bits as well. 350 */ 351 #define pgprot_cacheable(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WB) 352 #define pgprot_noncached(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_UC) 353 #define pgprot_writecombine(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WC) 354 355 struct file; 356 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 357 unsigned long size, pgprot_t vma_prot); 358 #define __HAVE_PHYS_MEM_ACCESS_PROT 359 360 static inline unsigned long 361 pgd_index (unsigned long address) 362 { 363 unsigned long region = address >> 61; 364 unsigned long l1index = (address >> PGDIR_SHIFT) & ((PTRS_PER_PGD >> 3) - 1); 365 366 return (region << (PAGE_SHIFT - 6)) | l1index; 367 } 368 369 /* The offset in the 1-level directory is given by the 3 region bits 370 (61..63) and the level-1 bits. */ 371 static inline pgd_t* 372 pgd_offset (const struct mm_struct *mm, unsigned long address) 373 { 374 return mm->pgd + pgd_index(address); 375 } 376 377 /* In the kernel's mapped region we completely ignore the region number 378 (since we know it's in region number 5). */ 379 #define pgd_offset_k(addr) \ 380 (init_mm.pgd + (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))) 381 382 /* Look up a pgd entry in the gate area. On IA-64, the gate-area 383 resides in the kernel-mapped segment, hence we use pgd_offset_k() 384 here. */ 385 #define pgd_offset_gate(mm, addr) pgd_offset_k(addr) 386 387 #if CONFIG_PGTABLE_LEVELS == 4 388 /* Find an entry in the second-level page table.. */ 389 #define pud_offset(dir,addr) \ 390 ((pud_t *) pgd_page_vaddr(*(dir)) + (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))) 391 #endif 392 393 /* Find an entry in the third-level page table.. */ 394 #define pmd_offset(dir,addr) \ 395 ((pmd_t *) pud_page_vaddr(*(dir)) + (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))) 396 397 /* 398 * Find an entry in the third-level page table. This looks more complicated than it 399 * should be because some platforms place page tables in high memory. 400 */ 401 #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) 402 #define pte_offset_kernel(dir,addr) ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr)) 403 #define pte_offset_map(dir,addr) pte_offset_kernel(dir, addr) 404 #define pte_unmap(pte) do { } while (0) 405 406 /* atomic versions of the some PTE manipulations: */ 407 408 static inline int 409 ptep_test_and_clear_young (struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) 410 { 411 #ifdef CONFIG_SMP 412 if (!pte_young(*ptep)) 413 return 0; 414 return test_and_clear_bit(_PAGE_A_BIT, ptep); 415 #else 416 pte_t pte = *ptep; 417 if (!pte_young(pte)) 418 return 0; 419 set_pte_at(vma->vm_mm, addr, ptep, pte_mkold(pte)); 420 return 1; 421 #endif 422 } 423 424 static inline pte_t 425 ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) 426 { 427 #ifdef CONFIG_SMP 428 return __pte(xchg((long *) ptep, 0)); 429 #else 430 pte_t pte = *ptep; 431 pte_clear(mm, addr, ptep); 432 return pte; 433 #endif 434 } 435 436 static inline void 437 ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) 438 { 439 #ifdef CONFIG_SMP 440 unsigned long new, old; 441 442 do { 443 old = pte_val(*ptep); 444 new = pte_val(pte_wrprotect(__pte (old))); 445 } while (cmpxchg((unsigned long *) ptep, old, new) != old); 446 #else 447 pte_t old_pte = *ptep; 448 set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte)); 449 #endif 450 } 451 452 static inline int 453 pte_same (pte_t a, pte_t b) 454 { 455 return pte_val(a) == pte_val(b); 456 } 457 458 #define update_mmu_cache(vma, address, ptep) do { } while (0) 459 460 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 461 extern void paging_init (void); 462 463 /* 464 * Note: The macros below rely on the fact that MAX_SWAPFILES_SHIFT <= number of 465 * bits in the swap-type field of the swap pte. It would be nice to 466 * enforce that, but we can't easily include <linux/swap.h> here. 467 * (Of course, better still would be to define MAX_SWAPFILES_SHIFT here...). 468 * 469 * Format of swap pte: 470 * bit 0 : present bit (must be zero) 471 * bits 1- 7: swap-type 472 * bits 8-62: swap offset 473 * bit 63 : _PAGE_PROTNONE bit 474 */ 475 #define __swp_type(entry) (((entry).val >> 1) & 0x7f) 476 #define __swp_offset(entry) (((entry).val << 1) >> 9) 477 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << 1) | ((long) (offset) << 8) }) 478 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 479 #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) 480 481 /* 482 * ZERO_PAGE is a global shared page that is always zero: used 483 * for zero-mapped memory areas etc.. 484 */ 485 extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)]; 486 extern struct page *zero_page_memmap_ptr; 487 #define ZERO_PAGE(vaddr) (zero_page_memmap_ptr) 488 489 /* We provide our own get_unmapped_area to cope with VA holes for userland */ 490 #define HAVE_ARCH_UNMAPPED_AREA 491 492 #ifdef CONFIG_HUGETLB_PAGE 493 #define HUGETLB_PGDIR_SHIFT (HPAGE_SHIFT + 2*(PAGE_SHIFT-3)) 494 #define HUGETLB_PGDIR_SIZE (__IA64_UL(1) << HUGETLB_PGDIR_SHIFT) 495 #define HUGETLB_PGDIR_MASK (~(HUGETLB_PGDIR_SIZE-1)) 496 #endif 497 498 499 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS 500 /* 501 * Update PTEP with ENTRY, which is guaranteed to be a less 502 * restrictive PTE. That is, ENTRY may have the ACCESSED, DIRTY, and 503 * WRITABLE bits turned on, when the value at PTEP did not. The 504 * WRITABLE bit may only be turned if SAFELY_WRITABLE is TRUE. 505 * 506 * SAFELY_WRITABLE is TRUE if we can update the value at PTEP without 507 * having to worry about races. On SMP machines, there are only two 508 * cases where this is true: 509 * 510 * (1) *PTEP has the PRESENT bit turned OFF 511 * (2) ENTRY has the DIRTY bit turned ON 512 * 513 * On ia64, we could implement this routine with a cmpxchg()-loop 514 * which ORs in the _PAGE_A/_PAGE_D bit if they're set in ENTRY. 515 * However, like on x86, we can get a more streamlined version by 516 * observing that it is OK to drop ACCESSED bit updates when 517 * SAFELY_WRITABLE is FALSE. Besides being rare, all that would do is 518 * result in an extra Access-bit fault, which would then turn on the 519 * ACCESSED bit in the low-level fault handler (iaccess_bit or 520 * daccess_bit in ivt.S). 521 */ 522 #ifdef CONFIG_SMP 523 # define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \ 524 ({ \ 525 int __changed = !pte_same(*(__ptep), __entry); \ 526 if (__changed && __safely_writable) { \ 527 set_pte(__ptep, __entry); \ 528 flush_tlb_page(__vma, __addr); \ 529 } \ 530 __changed; \ 531 }) 532 #else 533 # define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \ 534 ({ \ 535 int __changed = !pte_same(*(__ptep), __entry); \ 536 if (__changed) { \ 537 set_pte_at((__vma)->vm_mm, (__addr), __ptep, __entry); \ 538 flush_tlb_page(__vma, __addr); \ 539 } \ 540 __changed; \ 541 }) 542 #endif 543 544 # ifdef CONFIG_VIRTUAL_MEM_MAP 545 /* arch mem_map init routine is needed due to holes in a virtual mem_map */ 546 # define __HAVE_ARCH_MEMMAP_INIT 547 extern void memmap_init (unsigned long size, int nid, unsigned long zone, 548 unsigned long start_pfn); 549 # endif /* CONFIG_VIRTUAL_MEM_MAP */ 550 # endif /* !__ASSEMBLY__ */ 551 552 /* 553 * Identity-mapped regions use a large page size. We'll call such large pages 554 * "granules". If you can think of a better name that's unambiguous, let me 555 * know... 556 */ 557 #if defined(CONFIG_IA64_GRANULE_64MB) 558 # define IA64_GRANULE_SHIFT _PAGE_SIZE_64M 559 #elif defined(CONFIG_IA64_GRANULE_16MB) 560 # define IA64_GRANULE_SHIFT _PAGE_SIZE_16M 561 #endif 562 #define IA64_GRANULE_SIZE (1 << IA64_GRANULE_SHIFT) 563 /* 564 * log2() of the page size we use to map the kernel image (IA64_TR_KERNEL): 565 */ 566 #define KERNEL_TR_PAGE_SHIFT _PAGE_SIZE_64M 567 #define KERNEL_TR_PAGE_SIZE (1 << KERNEL_TR_PAGE_SHIFT) 568 569 /* 570 * No page table caches to initialise 571 */ 572 #define pgtable_cache_init() do { } while (0) 573 574 /* These tell get_user_pages() that the first gate page is accessible from user-level. */ 575 #define FIXADDR_USER_START GATE_ADDR 576 #ifdef HAVE_BUGGY_SEGREL 577 # define FIXADDR_USER_END (GATE_ADDR + 2*PAGE_SIZE) 578 #else 579 # define FIXADDR_USER_END (GATE_ADDR + 2*PERCPU_PAGE_SIZE) 580 #endif 581 582 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG 583 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR 584 #define __HAVE_ARCH_PTEP_SET_WRPROTECT 585 #define __HAVE_ARCH_PTE_SAME 586 #define __HAVE_ARCH_PGD_OFFSET_GATE 587 588 589 #if CONFIG_PGTABLE_LEVELS == 3 590 #include <asm-generic/pgtable-nopud.h> 591 #endif 592 #include <asm-generic/pgtable.h> 593 594 #endif /* _ASM_IA64_PGTABLE_H */ 595