1 /* 2 * include/asm-s390/pgtable.h 3 * 4 * S390 version 5 * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation 6 * Author(s): Hartmut Penner (hp@de.ibm.com) 7 * Ulrich Weigand (weigand@de.ibm.com) 8 * Martin Schwidefsky (schwidefsky@de.ibm.com) 9 * 10 * Derived from "include/asm-i386/pgtable.h" 11 */ 12 13 #ifndef _ASM_S390_PGTABLE_H 14 #define _ASM_S390_PGTABLE_H 15 16 /* 17 * The Linux memory management assumes a three-level page table setup. For 18 * s390 31 bit we "fold" the mid level into the top-level page table, so 19 * that we physically have the same two-level page table as the s390 mmu 20 * expects in 31 bit mode. For s390 64 bit we use three of the five levels 21 * the hardware provides (region first and region second tables are not 22 * used). 23 * 24 * The "pgd_xxx()" functions are trivial for a folded two-level 25 * setup: the pgd is never bad, and a pmd always exists (as it's folded 26 * into the pgd entry) 27 * 28 * This file contains the functions and defines necessary to modify and use 29 * the S390 page table tree. 30 */ 31 #ifndef __ASSEMBLY__ 32 #include <linux/sched.h> 33 #include <linux/mm_types.h> 34 #include <asm/bug.h> 35 #include <asm/page.h> 36 37 extern pgd_t swapper_pg_dir[] __attribute__ ((aligned (4096))); 38 extern void paging_init(void); 39 extern void vmem_map_init(void); 40 extern void fault_init(void); 41 42 /* 43 * The S390 doesn't have any external MMU info: the kernel page 44 * tables contain all the necessary information. 45 */ 46 #define update_mmu_cache(vma, address, ptep) do { } while (0) 47 48 /* 49 * ZERO_PAGE is a global shared page that is always zero; used 50 * for zero-mapped memory areas etc.. 51 */ 52 53 extern unsigned long empty_zero_page; 54 extern unsigned long zero_page_mask; 55 56 #define ZERO_PAGE(vaddr) \ 57 (virt_to_page((void *)(empty_zero_page + \ 58 (((unsigned long)(vaddr)) &zero_page_mask)))) 59 60 #define is_zero_pfn is_zero_pfn 61 static inline int is_zero_pfn(unsigned long pfn) 62 { 63 extern unsigned long zero_pfn; 64 unsigned long offset_from_zero_pfn = pfn - zero_pfn; 65 return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT); 66 } 67 68 #define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr)) 69 70 #endif /* !__ASSEMBLY__ */ 71 72 /* 73 * PMD_SHIFT determines the size of the area a second-level page 74 * table can map 75 * PGDIR_SHIFT determines what a third-level page table entry can map 76 */ 77 #ifndef __s390x__ 78 # define PMD_SHIFT 20 79 # define PUD_SHIFT 20 80 # define PGDIR_SHIFT 20 81 #else /* __s390x__ */ 82 # define PMD_SHIFT 20 83 # define PUD_SHIFT 31 84 # define PGDIR_SHIFT 42 85 #endif /* __s390x__ */ 86 87 #define PMD_SIZE (1UL << PMD_SHIFT) 88 #define PMD_MASK (~(PMD_SIZE-1)) 89 #define PUD_SIZE (1UL << PUD_SHIFT) 90 #define PUD_MASK (~(PUD_SIZE-1)) 91 #define PGDIR_SIZE (1UL << PGDIR_SHIFT) 92 #define PGDIR_MASK (~(PGDIR_SIZE-1)) 93 94 /* 95 * entries per page directory level: the S390 is two-level, so 96 * we don't really have any PMD directory physically. 97 * for S390 segment-table entries are combined to one PGD 98 * that leads to 1024 pte per pgd 99 */ 100 #define PTRS_PER_PTE 256 101 #ifndef __s390x__ 102 #define PTRS_PER_PMD 1 103 #define PTRS_PER_PUD 1 104 #else /* __s390x__ */ 105 #define PTRS_PER_PMD 2048 106 #define PTRS_PER_PUD 2048 107 #endif /* __s390x__ */ 108 #define PTRS_PER_PGD 2048 109 110 #define FIRST_USER_ADDRESS 0 111 112 #define pte_ERROR(e) \ 113 printk("%s:%d: bad pte %p.\n", __FILE__, __LINE__, (void *) pte_val(e)) 114 #define pmd_ERROR(e) \ 115 printk("%s:%d: bad pmd %p.\n", __FILE__, __LINE__, (void *) pmd_val(e)) 116 #define pud_ERROR(e) \ 117 printk("%s:%d: bad pud %p.\n", __FILE__, __LINE__, (void *) pud_val(e)) 118 #define pgd_ERROR(e) \ 119 printk("%s:%d: bad pgd %p.\n", __FILE__, __LINE__, (void *) pgd_val(e)) 120 121 #ifndef __ASSEMBLY__ 122 /* 123 * The vmalloc area will always be on the topmost area of the kernel 124 * mapping. We reserve 96MB (31bit) / 128GB (64bit) for vmalloc, 125 * which should be enough for any sane case. 126 * By putting vmalloc at the top, we maximise the gap between physical 127 * memory and vmalloc to catch misplaced memory accesses. As a side 128 * effect, this also makes sure that 64 bit module code cannot be used 129 * as system call address. 130 */ 131 132 extern unsigned long VMALLOC_START; 133 134 #ifndef __s390x__ 135 #define VMALLOC_SIZE (96UL << 20) 136 #define VMALLOC_END 0x7e000000UL 137 #define VMEM_MAP_END 0x80000000UL 138 #else /* __s390x__ */ 139 #define VMALLOC_SIZE (128UL << 30) 140 #define VMALLOC_END 0x3e000000000UL 141 #define VMEM_MAP_END 0x40000000000UL 142 #endif /* __s390x__ */ 143 144 /* 145 * VMEM_MAX_PHYS is the highest physical address that can be added to the 1:1 146 * mapping. This needs to be calculated at compile time since the size of the 147 * VMEM_MAP is static but the size of struct page can change. 148 */ 149 #define VMEM_MAX_PAGES ((VMEM_MAP_END - VMALLOC_END) / sizeof(struct page)) 150 #define VMEM_MAX_PFN min(VMALLOC_START >> PAGE_SHIFT, VMEM_MAX_PAGES) 151 #define VMEM_MAX_PHYS ((VMEM_MAX_PFN << PAGE_SHIFT) & ~((16 << 20) - 1)) 152 #define vmemmap ((struct page *) VMALLOC_END) 153 154 /* 155 * A 31 bit pagetable entry of S390 has following format: 156 * | PFRA | | OS | 157 * 0 0IP0 158 * 00000000001111111111222222222233 159 * 01234567890123456789012345678901 160 * 161 * I Page-Invalid Bit: Page is not available for address-translation 162 * P Page-Protection Bit: Store access not possible for page 163 * 164 * A 31 bit segmenttable entry of S390 has following format: 165 * | P-table origin | |PTL 166 * 0 IC 167 * 00000000001111111111222222222233 168 * 01234567890123456789012345678901 169 * 170 * I Segment-Invalid Bit: Segment is not available for address-translation 171 * C Common-Segment Bit: Segment is not private (PoP 3-30) 172 * PTL Page-Table-Length: Page-table length (PTL+1*16 entries -> up to 256) 173 * 174 * The 31 bit segmenttable origin of S390 has following format: 175 * 176 * |S-table origin | | STL | 177 * X **GPS 178 * 00000000001111111111222222222233 179 * 01234567890123456789012345678901 180 * 181 * X Space-Switch event: 182 * G Segment-Invalid Bit: * 183 * P Private-Space Bit: Segment is not private (PoP 3-30) 184 * S Storage-Alteration: 185 * STL Segment-Table-Length: Segment-table length (STL+1*16 entries -> up to 2048) 186 * 187 * A 64 bit pagetable entry of S390 has following format: 188 * | PFRA |0IPC| OS | 189 * 0000000000111111111122222222223333333333444444444455555555556666 190 * 0123456789012345678901234567890123456789012345678901234567890123 191 * 192 * I Page-Invalid Bit: Page is not available for address-translation 193 * P Page-Protection Bit: Store access not possible for page 194 * C Change-bit override: HW is not required to set change bit 195 * 196 * A 64 bit segmenttable entry of S390 has following format: 197 * | P-table origin | TT 198 * 0000000000111111111122222222223333333333444444444455555555556666 199 * 0123456789012345678901234567890123456789012345678901234567890123 200 * 201 * I Segment-Invalid Bit: Segment is not available for address-translation 202 * C Common-Segment Bit: Segment is not private (PoP 3-30) 203 * P Page-Protection Bit: Store access not possible for page 204 * TT Type 00 205 * 206 * A 64 bit region table entry of S390 has following format: 207 * | S-table origin | TF TTTL 208 * 0000000000111111111122222222223333333333444444444455555555556666 209 * 0123456789012345678901234567890123456789012345678901234567890123 210 * 211 * I Segment-Invalid Bit: Segment is not available for address-translation 212 * TT Type 01 213 * TF 214 * TL Table length 215 * 216 * The 64 bit regiontable origin of S390 has following format: 217 * | region table origon | DTTL 218 * 0000000000111111111122222222223333333333444444444455555555556666 219 * 0123456789012345678901234567890123456789012345678901234567890123 220 * 221 * X Space-Switch event: 222 * G Segment-Invalid Bit: 223 * P Private-Space Bit: 224 * S Storage-Alteration: 225 * R Real space 226 * TL Table-Length: 227 * 228 * A storage key has the following format: 229 * | ACC |F|R|C|0| 230 * 0 3 4 5 6 7 231 * ACC: access key 232 * F : fetch protection bit 233 * R : referenced bit 234 * C : changed bit 235 */ 236 237 /* Hardware bits in the page table entry */ 238 #define _PAGE_CO 0x100 /* HW Change-bit override */ 239 #define _PAGE_RO 0x200 /* HW read-only bit */ 240 #define _PAGE_INVALID 0x400 /* HW invalid bit */ 241 242 /* Software bits in the page table entry */ 243 #define _PAGE_SWT 0x001 /* SW pte type bit t */ 244 #define _PAGE_SWX 0x002 /* SW pte type bit x */ 245 #define _PAGE_SWC 0x004 /* SW pte changed bit (for KVM) */ 246 #define _PAGE_SWR 0x008 /* SW pte referenced bit (for KVM) */ 247 #define _PAGE_SPECIAL 0x010 /* SW associated with special page */ 248 #define __HAVE_ARCH_PTE_SPECIAL 249 250 /* Set of bits not changed in pte_modify */ 251 #define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_SPECIAL | _PAGE_SWC | _PAGE_SWR) 252 253 /* Six different types of pages. */ 254 #define _PAGE_TYPE_EMPTY 0x400 255 #define _PAGE_TYPE_NONE 0x401 256 #define _PAGE_TYPE_SWAP 0x403 257 #define _PAGE_TYPE_FILE 0x601 /* bit 0x002 is used for offset !! */ 258 #define _PAGE_TYPE_RO 0x200 259 #define _PAGE_TYPE_RW 0x000 260 261 /* 262 * Only four types for huge pages, using the invalid bit and protection bit 263 * of a segment table entry. 264 */ 265 #define _HPAGE_TYPE_EMPTY 0x020 /* _SEGMENT_ENTRY_INV */ 266 #define _HPAGE_TYPE_NONE 0x220 267 #define _HPAGE_TYPE_RO 0x200 /* _SEGMENT_ENTRY_RO */ 268 #define _HPAGE_TYPE_RW 0x000 269 270 /* 271 * PTE type bits are rather complicated. handle_pte_fault uses pte_present, 272 * pte_none and pte_file to find out the pte type WITHOUT holding the page 273 * table lock. ptep_clear_flush on the other hand uses ptep_clear_flush to 274 * invalidate a given pte. ipte sets the hw invalid bit and clears all tlbs 275 * for the page. The page table entry is set to _PAGE_TYPE_EMPTY afterwards. 276 * This change is done while holding the lock, but the intermediate step 277 * of a previously valid pte with the hw invalid bit set can be observed by 278 * handle_pte_fault. That makes it necessary that all valid pte types with 279 * the hw invalid bit set must be distinguishable from the four pte types 280 * empty, none, swap and file. 281 * 282 * irxt ipte irxt 283 * _PAGE_TYPE_EMPTY 1000 -> 1000 284 * _PAGE_TYPE_NONE 1001 -> 1001 285 * _PAGE_TYPE_SWAP 1011 -> 1011 286 * _PAGE_TYPE_FILE 11?1 -> 11?1 287 * _PAGE_TYPE_RO 0100 -> 1100 288 * _PAGE_TYPE_RW 0000 -> 1000 289 * 290 * pte_none is true for bits combinations 1000, 1010, 1100, 1110 291 * pte_present is true for bits combinations 0000, 0010, 0100, 0110, 1001 292 * pte_file is true for bits combinations 1101, 1111 293 * swap pte is 1011 and 0001, 0011, 0101, 0111 are invalid. 294 */ 295 296 #ifndef __s390x__ 297 298 /* Bits in the segment table address-space-control-element */ 299 #define _ASCE_SPACE_SWITCH 0x80000000UL /* space switch event */ 300 #define _ASCE_ORIGIN_MASK 0x7ffff000UL /* segment table origin */ 301 #define _ASCE_PRIVATE_SPACE 0x100 /* private space control */ 302 #define _ASCE_ALT_EVENT 0x80 /* storage alteration event control */ 303 #define _ASCE_TABLE_LENGTH 0x7f /* 128 x 64 entries = 8k */ 304 305 /* Bits in the segment table entry */ 306 #define _SEGMENT_ENTRY_ORIGIN 0x7fffffc0UL /* page table origin */ 307 #define _SEGMENT_ENTRY_RO 0x200 /* page protection bit */ 308 #define _SEGMENT_ENTRY_INV 0x20 /* invalid segment table entry */ 309 #define _SEGMENT_ENTRY_COMMON 0x10 /* common segment bit */ 310 #define _SEGMENT_ENTRY_PTL 0x0f /* page table length */ 311 312 #define _SEGMENT_ENTRY (_SEGMENT_ENTRY_PTL) 313 #define _SEGMENT_ENTRY_EMPTY (_SEGMENT_ENTRY_INV) 314 315 /* Page status table bits for virtualization */ 316 #define RCP_ACC_BITS 0xf0000000UL 317 #define RCP_FP_BIT 0x08000000UL 318 #define RCP_PCL_BIT 0x00800000UL 319 #define RCP_HR_BIT 0x00400000UL 320 #define RCP_HC_BIT 0x00200000UL 321 #define RCP_GR_BIT 0x00040000UL 322 #define RCP_GC_BIT 0x00020000UL 323 324 /* User dirty / referenced bit for KVM's migration feature */ 325 #define KVM_UR_BIT 0x00008000UL 326 #define KVM_UC_BIT 0x00004000UL 327 328 #else /* __s390x__ */ 329 330 /* Bits in the segment/region table address-space-control-element */ 331 #define _ASCE_ORIGIN ~0xfffUL/* segment table origin */ 332 #define _ASCE_PRIVATE_SPACE 0x100 /* private space control */ 333 #define _ASCE_ALT_EVENT 0x80 /* storage alteration event control */ 334 #define _ASCE_SPACE_SWITCH 0x40 /* space switch event */ 335 #define _ASCE_REAL_SPACE 0x20 /* real space control */ 336 #define _ASCE_TYPE_MASK 0x0c /* asce table type mask */ 337 #define _ASCE_TYPE_REGION1 0x0c /* region first table type */ 338 #define _ASCE_TYPE_REGION2 0x08 /* region second table type */ 339 #define _ASCE_TYPE_REGION3 0x04 /* region third table type */ 340 #define _ASCE_TYPE_SEGMENT 0x00 /* segment table type */ 341 #define _ASCE_TABLE_LENGTH 0x03 /* region table length */ 342 343 /* Bits in the region table entry */ 344 #define _REGION_ENTRY_ORIGIN ~0xfffUL/* region/segment table origin */ 345 #define _REGION_ENTRY_INV 0x20 /* invalid region table entry */ 346 #define _REGION_ENTRY_TYPE_MASK 0x0c /* region/segment table type mask */ 347 #define _REGION_ENTRY_TYPE_R1 0x0c /* region first table type */ 348 #define _REGION_ENTRY_TYPE_R2 0x08 /* region second table type */ 349 #define _REGION_ENTRY_TYPE_R3 0x04 /* region third table type */ 350 #define _REGION_ENTRY_LENGTH 0x03 /* region third length */ 351 352 #define _REGION1_ENTRY (_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_LENGTH) 353 #define _REGION1_ENTRY_EMPTY (_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INV) 354 #define _REGION2_ENTRY (_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_LENGTH) 355 #define _REGION2_ENTRY_EMPTY (_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INV) 356 #define _REGION3_ENTRY (_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_LENGTH) 357 #define _REGION3_ENTRY_EMPTY (_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INV) 358 359 /* Bits in the segment table entry */ 360 #define _SEGMENT_ENTRY_ORIGIN ~0x7ffUL/* segment table origin */ 361 #define _SEGMENT_ENTRY_RO 0x200 /* page protection bit */ 362 #define _SEGMENT_ENTRY_INV 0x20 /* invalid segment table entry */ 363 364 #define _SEGMENT_ENTRY (0) 365 #define _SEGMENT_ENTRY_EMPTY (_SEGMENT_ENTRY_INV) 366 367 #define _SEGMENT_ENTRY_LARGE 0x400 /* STE-format control, large page */ 368 #define _SEGMENT_ENTRY_CO 0x100 /* change-recording override */ 369 370 /* Page status table bits for virtualization */ 371 #define RCP_ACC_BITS 0xf000000000000000UL 372 #define RCP_FP_BIT 0x0800000000000000UL 373 #define RCP_PCL_BIT 0x0080000000000000UL 374 #define RCP_HR_BIT 0x0040000000000000UL 375 #define RCP_HC_BIT 0x0020000000000000UL 376 #define RCP_GR_BIT 0x0004000000000000UL 377 #define RCP_GC_BIT 0x0002000000000000UL 378 379 /* User dirty / referenced bit for KVM's migration feature */ 380 #define KVM_UR_BIT 0x0000800000000000UL 381 #define KVM_UC_BIT 0x0000400000000000UL 382 383 #endif /* __s390x__ */ 384 385 /* 386 * A user page table pointer has the space-switch-event bit, the 387 * private-space-control bit and the storage-alteration-event-control 388 * bit set. A kernel page table pointer doesn't need them. 389 */ 390 #define _ASCE_USER_BITS (_ASCE_SPACE_SWITCH | _ASCE_PRIVATE_SPACE | \ 391 _ASCE_ALT_EVENT) 392 393 /* 394 * Page protection definitions. 395 */ 396 #define PAGE_NONE __pgprot(_PAGE_TYPE_NONE) 397 #define PAGE_RO __pgprot(_PAGE_TYPE_RO) 398 #define PAGE_RW __pgprot(_PAGE_TYPE_RW) 399 400 #define PAGE_KERNEL PAGE_RW 401 #define PAGE_COPY PAGE_RO 402 403 /* 404 * On s390 the page table entry has an invalid bit and a read-only bit. 405 * Read permission implies execute permission and write permission 406 * implies read permission. 407 */ 408 /*xwr*/ 409 #define __P000 PAGE_NONE 410 #define __P001 PAGE_RO 411 #define __P010 PAGE_RO 412 #define __P011 PAGE_RO 413 #define __P100 PAGE_RO 414 #define __P101 PAGE_RO 415 #define __P110 PAGE_RO 416 #define __P111 PAGE_RO 417 418 #define __S000 PAGE_NONE 419 #define __S001 PAGE_RO 420 #define __S010 PAGE_RW 421 #define __S011 PAGE_RW 422 #define __S100 PAGE_RO 423 #define __S101 PAGE_RO 424 #define __S110 PAGE_RW 425 #define __S111 PAGE_RW 426 427 static inline int mm_exclusive(struct mm_struct *mm) 428 { 429 return likely(mm == current->active_mm && 430 atomic_read(&mm->context.attach_count) <= 1); 431 } 432 433 static inline int mm_has_pgste(struct mm_struct *mm) 434 { 435 #ifdef CONFIG_PGSTE 436 if (unlikely(mm->context.has_pgste)) 437 return 1; 438 #endif 439 return 0; 440 } 441 /* 442 * pgd/pmd/pte query functions 443 */ 444 #ifndef __s390x__ 445 446 static inline int pgd_present(pgd_t pgd) { return 1; } 447 static inline int pgd_none(pgd_t pgd) { return 0; } 448 static inline int pgd_bad(pgd_t pgd) { return 0; } 449 450 static inline int pud_present(pud_t pud) { return 1; } 451 static inline int pud_none(pud_t pud) { return 0; } 452 static inline int pud_bad(pud_t pud) { return 0; } 453 454 #else /* __s390x__ */ 455 456 static inline int pgd_present(pgd_t pgd) 457 { 458 if ((pgd_val(pgd) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R2) 459 return 1; 460 return (pgd_val(pgd) & _REGION_ENTRY_ORIGIN) != 0UL; 461 } 462 463 static inline int pgd_none(pgd_t pgd) 464 { 465 if ((pgd_val(pgd) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R2) 466 return 0; 467 return (pgd_val(pgd) & _REGION_ENTRY_INV) != 0UL; 468 } 469 470 static inline int pgd_bad(pgd_t pgd) 471 { 472 /* 473 * With dynamic page table levels the pgd can be a region table 474 * entry or a segment table entry. Check for the bit that are 475 * invalid for either table entry. 476 */ 477 unsigned long mask = 478 ~_SEGMENT_ENTRY_ORIGIN & ~_REGION_ENTRY_INV & 479 ~_REGION_ENTRY_TYPE_MASK & ~_REGION_ENTRY_LENGTH; 480 return (pgd_val(pgd) & mask) != 0; 481 } 482 483 static inline int pud_present(pud_t pud) 484 { 485 if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3) 486 return 1; 487 return (pud_val(pud) & _REGION_ENTRY_ORIGIN) != 0UL; 488 } 489 490 static inline int pud_none(pud_t pud) 491 { 492 if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3) 493 return 0; 494 return (pud_val(pud) & _REGION_ENTRY_INV) != 0UL; 495 } 496 497 static inline int pud_bad(pud_t pud) 498 { 499 /* 500 * With dynamic page table levels the pud can be a region table 501 * entry or a segment table entry. Check for the bit that are 502 * invalid for either table entry. 503 */ 504 unsigned long mask = 505 ~_SEGMENT_ENTRY_ORIGIN & ~_REGION_ENTRY_INV & 506 ~_REGION_ENTRY_TYPE_MASK & ~_REGION_ENTRY_LENGTH; 507 return (pud_val(pud) & mask) != 0; 508 } 509 510 #endif /* __s390x__ */ 511 512 static inline int pmd_present(pmd_t pmd) 513 { 514 return (pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN) != 0UL; 515 } 516 517 static inline int pmd_none(pmd_t pmd) 518 { 519 return (pmd_val(pmd) & _SEGMENT_ENTRY_INV) != 0UL; 520 } 521 522 static inline int pmd_bad(pmd_t pmd) 523 { 524 unsigned long mask = ~_SEGMENT_ENTRY_ORIGIN & ~_SEGMENT_ENTRY_INV; 525 return (pmd_val(pmd) & mask) != _SEGMENT_ENTRY; 526 } 527 528 static inline int pte_none(pte_t pte) 529 { 530 return (pte_val(pte) & _PAGE_INVALID) && !(pte_val(pte) & _PAGE_SWT); 531 } 532 533 static inline int pte_present(pte_t pte) 534 { 535 unsigned long mask = _PAGE_RO | _PAGE_INVALID | _PAGE_SWT | _PAGE_SWX; 536 return (pte_val(pte) & mask) == _PAGE_TYPE_NONE || 537 (!(pte_val(pte) & _PAGE_INVALID) && 538 !(pte_val(pte) & _PAGE_SWT)); 539 } 540 541 static inline int pte_file(pte_t pte) 542 { 543 unsigned long mask = _PAGE_RO | _PAGE_INVALID | _PAGE_SWT; 544 return (pte_val(pte) & mask) == _PAGE_TYPE_FILE; 545 } 546 547 static inline int pte_special(pte_t pte) 548 { 549 return (pte_val(pte) & _PAGE_SPECIAL); 550 } 551 552 #define __HAVE_ARCH_PTE_SAME 553 static inline int pte_same(pte_t a, pte_t b) 554 { 555 return pte_val(a) == pte_val(b); 556 } 557 558 static inline pgste_t pgste_get_lock(pte_t *ptep) 559 { 560 unsigned long new = 0; 561 #ifdef CONFIG_PGSTE 562 unsigned long old; 563 564 preempt_disable(); 565 asm( 566 " lg %0,%2\n" 567 "0: lgr %1,%0\n" 568 " nihh %0,0xff7f\n" /* clear RCP_PCL_BIT in old */ 569 " oihh %1,0x0080\n" /* set RCP_PCL_BIT in new */ 570 " csg %0,%1,%2\n" 571 " jl 0b\n" 572 : "=&d" (old), "=&d" (new), "=Q" (ptep[PTRS_PER_PTE]) 573 : "Q" (ptep[PTRS_PER_PTE]) : "cc"); 574 #endif 575 return __pgste(new); 576 } 577 578 static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste) 579 { 580 #ifdef CONFIG_PGSTE 581 asm( 582 " nihh %1,0xff7f\n" /* clear RCP_PCL_BIT */ 583 " stg %1,%0\n" 584 : "=Q" (ptep[PTRS_PER_PTE]) 585 : "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE]) : "cc"); 586 preempt_enable(); 587 #endif 588 } 589 590 static inline pgste_t pgste_update_all(pte_t *ptep, pgste_t pgste) 591 { 592 #ifdef CONFIG_PGSTE 593 unsigned long address, bits; 594 unsigned char skey; 595 596 if (!pte_present(*ptep)) 597 return pgste; 598 address = pte_val(*ptep) & PAGE_MASK; 599 skey = page_get_storage_key(address); 600 bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED); 601 /* Clear page changed & referenced bit in the storage key */ 602 if (bits) { 603 skey ^= bits; 604 page_set_storage_key(address, skey, 1); 605 } 606 /* Transfer page changed & referenced bit to guest bits in pgste */ 607 pgste_val(pgste) |= bits << 48; /* RCP_GR_BIT & RCP_GC_BIT */ 608 /* Get host changed & referenced bits from pgste */ 609 bits |= (pgste_val(pgste) & (RCP_HR_BIT | RCP_HC_BIT)) >> 52; 610 /* Clear host bits in pgste. */ 611 pgste_val(pgste) &= ~(RCP_HR_BIT | RCP_HC_BIT); 612 pgste_val(pgste) &= ~(RCP_ACC_BITS | RCP_FP_BIT); 613 /* Copy page access key and fetch protection bit to pgste */ 614 pgste_val(pgste) |= 615 (unsigned long) (skey & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56; 616 /* Transfer changed and referenced to kvm user bits */ 617 pgste_val(pgste) |= bits << 45; /* KVM_UR_BIT & KVM_UC_BIT */ 618 /* Transfer changed & referenced to pte sofware bits */ 619 pte_val(*ptep) |= bits << 1; /* _PAGE_SWR & _PAGE_SWC */ 620 #endif 621 return pgste; 622 623 } 624 625 static inline pgste_t pgste_update_young(pte_t *ptep, pgste_t pgste) 626 { 627 #ifdef CONFIG_PGSTE 628 int young; 629 630 if (!pte_present(*ptep)) 631 return pgste; 632 young = page_reset_referenced(pte_val(*ptep) & PAGE_MASK); 633 /* Transfer page referenced bit to pte software bit (host view) */ 634 if (young || (pgste_val(pgste) & RCP_HR_BIT)) 635 pte_val(*ptep) |= _PAGE_SWR; 636 /* Clear host referenced bit in pgste. */ 637 pgste_val(pgste) &= ~RCP_HR_BIT; 638 /* Transfer page referenced bit to guest bit in pgste */ 639 pgste_val(pgste) |= (unsigned long) young << 50; /* set RCP_GR_BIT */ 640 #endif 641 return pgste; 642 643 } 644 645 static inline void pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry) 646 { 647 #ifdef CONFIG_PGSTE 648 unsigned long address; 649 unsigned long okey, nkey; 650 651 if (!pte_present(entry)) 652 return; 653 address = pte_val(entry) & PAGE_MASK; 654 okey = nkey = page_get_storage_key(address); 655 nkey &= ~(_PAGE_ACC_BITS | _PAGE_FP_BIT); 656 /* Set page access key and fetch protection bit from pgste */ 657 nkey |= (pgste_val(pgste) & (RCP_ACC_BITS | RCP_FP_BIT)) >> 56; 658 if (okey != nkey) 659 page_set_storage_key(address, nkey, 1); 660 #endif 661 } 662 663 /** 664 * struct gmap_struct - guest address space 665 * @mm: pointer to the parent mm_struct 666 * @table: pointer to the page directory 667 * @asce: address space control element for gmap page table 668 * @crst_list: list of all crst tables used in the guest address space 669 */ 670 struct gmap { 671 struct list_head list; 672 struct mm_struct *mm; 673 unsigned long *table; 674 unsigned long asce; 675 struct list_head crst_list; 676 }; 677 678 /** 679 * struct gmap_rmap - reverse mapping for segment table entries 680 * @next: pointer to the next gmap_rmap structure in the list 681 * @entry: pointer to a segment table entry 682 */ 683 struct gmap_rmap { 684 struct list_head list; 685 unsigned long *entry; 686 }; 687 688 /** 689 * struct gmap_pgtable - gmap information attached to a page table 690 * @vmaddr: address of the 1MB segment in the process virtual memory 691 * @mapper: list of segment table entries maping a page table 692 */ 693 struct gmap_pgtable { 694 unsigned long vmaddr; 695 struct list_head mapper; 696 }; 697 698 struct gmap *gmap_alloc(struct mm_struct *mm); 699 void gmap_free(struct gmap *gmap); 700 void gmap_enable(struct gmap *gmap); 701 void gmap_disable(struct gmap *gmap); 702 int gmap_map_segment(struct gmap *gmap, unsigned long from, 703 unsigned long to, unsigned long length); 704 int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len); 705 unsigned long __gmap_fault(unsigned long address, struct gmap *); 706 unsigned long gmap_fault(unsigned long address, struct gmap *); 707 void gmap_discard(unsigned long from, unsigned long to, struct gmap *); 708 709 /* 710 * Certain architectures need to do special things when PTEs 711 * within a page table are directly modified. Thus, the following 712 * hook is made available. 713 */ 714 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 715 pte_t *ptep, pte_t entry) 716 { 717 pgste_t pgste; 718 719 if (mm_has_pgste(mm)) { 720 pgste = pgste_get_lock(ptep); 721 pgste_set_pte(ptep, pgste, entry); 722 *ptep = entry; 723 pgste_set_unlock(ptep, pgste); 724 } else 725 *ptep = entry; 726 } 727 728 /* 729 * query functions pte_write/pte_dirty/pte_young only work if 730 * pte_present() is true. Undefined behaviour if not.. 731 */ 732 static inline int pte_write(pte_t pte) 733 { 734 return (pte_val(pte) & _PAGE_RO) == 0; 735 } 736 737 static inline int pte_dirty(pte_t pte) 738 { 739 #ifdef CONFIG_PGSTE 740 if (pte_val(pte) & _PAGE_SWC) 741 return 1; 742 #endif 743 return 0; 744 } 745 746 static inline int pte_young(pte_t pte) 747 { 748 #ifdef CONFIG_PGSTE 749 if (pte_val(pte) & _PAGE_SWR) 750 return 1; 751 #endif 752 return 0; 753 } 754 755 /* 756 * pgd/pmd/pte modification functions 757 */ 758 759 static inline void pgd_clear(pgd_t *pgd) 760 { 761 #ifdef __s390x__ 762 if ((pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R2) 763 pgd_val(*pgd) = _REGION2_ENTRY_EMPTY; 764 #endif 765 } 766 767 static inline void pud_clear(pud_t *pud) 768 { 769 #ifdef __s390x__ 770 if ((pud_val(*pud) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) 771 pud_val(*pud) = _REGION3_ENTRY_EMPTY; 772 #endif 773 } 774 775 static inline void pmd_clear(pmd_t *pmdp) 776 { 777 pmd_val(*pmdp) = _SEGMENT_ENTRY_EMPTY; 778 } 779 780 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) 781 { 782 pte_val(*ptep) = _PAGE_TYPE_EMPTY; 783 } 784 785 /* 786 * The following pte modification functions only work if 787 * pte_present() is true. Undefined behaviour if not.. 788 */ 789 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 790 { 791 pte_val(pte) &= _PAGE_CHG_MASK; 792 pte_val(pte) |= pgprot_val(newprot); 793 return pte; 794 } 795 796 static inline pte_t pte_wrprotect(pte_t pte) 797 { 798 /* Do not clobber _PAGE_TYPE_NONE pages! */ 799 if (!(pte_val(pte) & _PAGE_INVALID)) 800 pte_val(pte) |= _PAGE_RO; 801 return pte; 802 } 803 804 static inline pte_t pte_mkwrite(pte_t pte) 805 { 806 pte_val(pte) &= ~_PAGE_RO; 807 return pte; 808 } 809 810 static inline pte_t pte_mkclean(pte_t pte) 811 { 812 #ifdef CONFIG_PGSTE 813 pte_val(pte) &= ~_PAGE_SWC; 814 #endif 815 return pte; 816 } 817 818 static inline pte_t pte_mkdirty(pte_t pte) 819 { 820 return pte; 821 } 822 823 static inline pte_t pte_mkold(pte_t pte) 824 { 825 #ifdef CONFIG_PGSTE 826 pte_val(pte) &= ~_PAGE_SWR; 827 #endif 828 return pte; 829 } 830 831 static inline pte_t pte_mkyoung(pte_t pte) 832 { 833 return pte; 834 } 835 836 static inline pte_t pte_mkspecial(pte_t pte) 837 { 838 pte_val(pte) |= _PAGE_SPECIAL; 839 return pte; 840 } 841 842 #ifdef CONFIG_HUGETLB_PAGE 843 static inline pte_t pte_mkhuge(pte_t pte) 844 { 845 /* 846 * PROT_NONE needs to be remapped from the pte type to the ste type. 847 * The HW invalid bit is also different for pte and ste. The pte 848 * invalid bit happens to be the same as the ste _SEGMENT_ENTRY_LARGE 849 * bit, so we don't have to clear it. 850 */ 851 if (pte_val(pte) & _PAGE_INVALID) { 852 if (pte_val(pte) & _PAGE_SWT) 853 pte_val(pte) |= _HPAGE_TYPE_NONE; 854 pte_val(pte) |= _SEGMENT_ENTRY_INV; 855 } 856 /* 857 * Clear SW pte bits SWT and SWX, there are no SW bits in a segment 858 * table entry. 859 */ 860 pte_val(pte) &= ~(_PAGE_SWT | _PAGE_SWX); 861 /* 862 * Also set the change-override bit because we don't need dirty bit 863 * tracking for hugetlbfs pages. 864 */ 865 pte_val(pte) |= (_SEGMENT_ENTRY_LARGE | _SEGMENT_ENTRY_CO); 866 return pte; 867 } 868 #endif 869 870 /* 871 * Get (and clear) the user dirty bit for a pte. 872 */ 873 static inline int ptep_test_and_clear_user_dirty(struct mm_struct *mm, 874 pte_t *ptep) 875 { 876 pgste_t pgste; 877 int dirty = 0; 878 879 if (mm_has_pgste(mm)) { 880 pgste = pgste_get_lock(ptep); 881 pgste = pgste_update_all(ptep, pgste); 882 dirty = !!(pgste_val(pgste) & KVM_UC_BIT); 883 pgste_val(pgste) &= ~KVM_UC_BIT; 884 pgste_set_unlock(ptep, pgste); 885 return dirty; 886 } 887 return dirty; 888 } 889 890 /* 891 * Get (and clear) the user referenced bit for a pte. 892 */ 893 static inline int ptep_test_and_clear_user_young(struct mm_struct *mm, 894 pte_t *ptep) 895 { 896 pgste_t pgste; 897 int young = 0; 898 899 if (mm_has_pgste(mm)) { 900 pgste = pgste_get_lock(ptep); 901 pgste = pgste_update_young(ptep, pgste); 902 young = !!(pgste_val(pgste) & KVM_UR_BIT); 903 pgste_val(pgste) &= ~KVM_UR_BIT; 904 pgste_set_unlock(ptep, pgste); 905 } 906 return young; 907 } 908 909 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG 910 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, 911 unsigned long addr, pte_t *ptep) 912 { 913 pgste_t pgste; 914 pte_t pte; 915 916 if (mm_has_pgste(vma->vm_mm)) { 917 pgste = pgste_get_lock(ptep); 918 pgste = pgste_update_young(ptep, pgste); 919 pte = *ptep; 920 *ptep = pte_mkold(pte); 921 pgste_set_unlock(ptep, pgste); 922 return pte_young(pte); 923 } 924 return 0; 925 } 926 927 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH 928 static inline int ptep_clear_flush_young(struct vm_area_struct *vma, 929 unsigned long address, pte_t *ptep) 930 { 931 /* No need to flush TLB 932 * On s390 reference bits are in storage key and never in TLB 933 * With virtualization we handle the reference bit, without we 934 * we can simply return */ 935 return ptep_test_and_clear_young(vma, address, ptep); 936 } 937 938 static inline void __ptep_ipte(unsigned long address, pte_t *ptep) 939 { 940 if (!(pte_val(*ptep) & _PAGE_INVALID)) { 941 #ifndef __s390x__ 942 /* pto must point to the start of the segment table */ 943 pte_t *pto = (pte_t *) (((unsigned long) ptep) & 0x7ffffc00); 944 #else 945 /* ipte in zarch mode can do the math */ 946 pte_t *pto = ptep; 947 #endif 948 asm volatile( 949 " ipte %2,%3" 950 : "=m" (*ptep) : "m" (*ptep), 951 "a" (pto), "a" (address)); 952 } 953 } 954 955 /* 956 * This is hard to understand. ptep_get_and_clear and ptep_clear_flush 957 * both clear the TLB for the unmapped pte. The reason is that 958 * ptep_get_and_clear is used in common code (e.g. change_pte_range) 959 * to modify an active pte. The sequence is 960 * 1) ptep_get_and_clear 961 * 2) set_pte_at 962 * 3) flush_tlb_range 963 * On s390 the tlb needs to get flushed with the modification of the pte 964 * if the pte is active. The only way how this can be implemented is to 965 * have ptep_get_and_clear do the tlb flush. In exchange flush_tlb_range 966 * is a nop. 967 */ 968 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR 969 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, 970 unsigned long address, pte_t *ptep) 971 { 972 pgste_t pgste; 973 pte_t pte; 974 975 mm->context.flush_mm = 1; 976 if (mm_has_pgste(mm)) 977 pgste = pgste_get_lock(ptep); 978 979 pte = *ptep; 980 if (!mm_exclusive(mm)) 981 __ptep_ipte(address, ptep); 982 pte_val(*ptep) = _PAGE_TYPE_EMPTY; 983 984 if (mm_has_pgste(mm)) { 985 pgste = pgste_update_all(&pte, pgste); 986 pgste_set_unlock(ptep, pgste); 987 } 988 return pte; 989 } 990 991 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION 992 static inline pte_t ptep_modify_prot_start(struct mm_struct *mm, 993 unsigned long address, 994 pte_t *ptep) 995 { 996 pte_t pte; 997 998 mm->context.flush_mm = 1; 999 if (mm_has_pgste(mm)) 1000 pgste_get_lock(ptep); 1001 1002 pte = *ptep; 1003 if (!mm_exclusive(mm)) 1004 __ptep_ipte(address, ptep); 1005 return pte; 1006 } 1007 1008 static inline void ptep_modify_prot_commit(struct mm_struct *mm, 1009 unsigned long address, 1010 pte_t *ptep, pte_t pte) 1011 { 1012 *ptep = pte; 1013 if (mm_has_pgste(mm)) 1014 pgste_set_unlock(ptep, *(pgste_t *)(ptep + PTRS_PER_PTE)); 1015 } 1016 1017 #define __HAVE_ARCH_PTEP_CLEAR_FLUSH 1018 static inline pte_t ptep_clear_flush(struct vm_area_struct *vma, 1019 unsigned long address, pte_t *ptep) 1020 { 1021 pgste_t pgste; 1022 pte_t pte; 1023 1024 if (mm_has_pgste(vma->vm_mm)) 1025 pgste = pgste_get_lock(ptep); 1026 1027 pte = *ptep; 1028 __ptep_ipte(address, ptep); 1029 pte_val(*ptep) = _PAGE_TYPE_EMPTY; 1030 1031 if (mm_has_pgste(vma->vm_mm)) { 1032 pgste = pgste_update_all(&pte, pgste); 1033 pgste_set_unlock(ptep, pgste); 1034 } 1035 return pte; 1036 } 1037 1038 /* 1039 * The batched pte unmap code uses ptep_get_and_clear_full to clear the 1040 * ptes. Here an optimization is possible. tlb_gather_mmu flushes all 1041 * tlbs of an mm if it can guarantee that the ptes of the mm_struct 1042 * cannot be accessed while the batched unmap is running. In this case 1043 * full==1 and a simple pte_clear is enough. See tlb.h. 1044 */ 1045 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL 1046 static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, 1047 unsigned long address, 1048 pte_t *ptep, int full) 1049 { 1050 pgste_t pgste; 1051 pte_t pte; 1052 1053 if (mm_has_pgste(mm)) 1054 pgste = pgste_get_lock(ptep); 1055 1056 pte = *ptep; 1057 if (!full) 1058 __ptep_ipte(address, ptep); 1059 pte_val(*ptep) = _PAGE_TYPE_EMPTY; 1060 1061 if (mm_has_pgste(mm)) { 1062 pgste = pgste_update_all(&pte, pgste); 1063 pgste_set_unlock(ptep, pgste); 1064 } 1065 return pte; 1066 } 1067 1068 #define __HAVE_ARCH_PTEP_SET_WRPROTECT 1069 static inline pte_t ptep_set_wrprotect(struct mm_struct *mm, 1070 unsigned long address, pte_t *ptep) 1071 { 1072 pgste_t pgste; 1073 pte_t pte = *ptep; 1074 1075 if (pte_write(pte)) { 1076 mm->context.flush_mm = 1; 1077 if (mm_has_pgste(mm)) 1078 pgste = pgste_get_lock(ptep); 1079 1080 if (!mm_exclusive(mm)) 1081 __ptep_ipte(address, ptep); 1082 *ptep = pte_wrprotect(pte); 1083 1084 if (mm_has_pgste(mm)) 1085 pgste_set_unlock(ptep, pgste); 1086 } 1087 return pte; 1088 } 1089 1090 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS 1091 static inline int ptep_set_access_flags(struct vm_area_struct *vma, 1092 unsigned long address, pte_t *ptep, 1093 pte_t entry, int dirty) 1094 { 1095 pgste_t pgste; 1096 1097 if (pte_same(*ptep, entry)) 1098 return 0; 1099 if (mm_has_pgste(vma->vm_mm)) 1100 pgste = pgste_get_lock(ptep); 1101 1102 __ptep_ipte(address, ptep); 1103 *ptep = entry; 1104 1105 if (mm_has_pgste(vma->vm_mm)) 1106 pgste_set_unlock(ptep, pgste); 1107 return 1; 1108 } 1109 1110 /* 1111 * Conversion functions: convert a page and protection to a page entry, 1112 * and a page entry and page directory to the page they refer to. 1113 */ 1114 static inline pte_t mk_pte_phys(unsigned long physpage, pgprot_t pgprot) 1115 { 1116 pte_t __pte; 1117 pte_val(__pte) = physpage + pgprot_val(pgprot); 1118 return __pte; 1119 } 1120 1121 static inline pte_t mk_pte(struct page *page, pgprot_t pgprot) 1122 { 1123 unsigned long physpage = page_to_phys(page); 1124 1125 return mk_pte_phys(physpage, pgprot); 1126 } 1127 1128 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1)) 1129 #define pud_index(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1)) 1130 #define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1)) 1131 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1)) 1132 1133 #define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address)) 1134 #define pgd_offset_k(address) pgd_offset(&init_mm, address) 1135 1136 #ifndef __s390x__ 1137 1138 #define pmd_deref(pmd) (pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN) 1139 #define pud_deref(pmd) ({ BUG(); 0UL; }) 1140 #define pgd_deref(pmd) ({ BUG(); 0UL; }) 1141 1142 #define pud_offset(pgd, address) ((pud_t *) pgd) 1143 #define pmd_offset(pud, address) ((pmd_t *) pud + pmd_index(address)) 1144 1145 #else /* __s390x__ */ 1146 1147 #define pmd_deref(pmd) (pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN) 1148 #define pud_deref(pud) (pud_val(pud) & _REGION_ENTRY_ORIGIN) 1149 #define pgd_deref(pgd) (pgd_val(pgd) & _REGION_ENTRY_ORIGIN) 1150 1151 static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address) 1152 { 1153 pud_t *pud = (pud_t *) pgd; 1154 if ((pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R2) 1155 pud = (pud_t *) pgd_deref(*pgd); 1156 return pud + pud_index(address); 1157 } 1158 1159 static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) 1160 { 1161 pmd_t *pmd = (pmd_t *) pud; 1162 if ((pud_val(*pud) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) 1163 pmd = (pmd_t *) pud_deref(*pud); 1164 return pmd + pmd_index(address); 1165 } 1166 1167 #endif /* __s390x__ */ 1168 1169 #define pfn_pte(pfn,pgprot) mk_pte_phys(__pa((pfn) << PAGE_SHIFT),(pgprot)) 1170 #define pte_pfn(x) (pte_val(x) >> PAGE_SHIFT) 1171 #define pte_page(x) pfn_to_page(pte_pfn(x)) 1172 1173 #define pmd_page(pmd) pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT) 1174 1175 /* Find an entry in the lowest level page table.. */ 1176 #define pte_offset(pmd, addr) ((pte_t *) pmd_deref(*(pmd)) + pte_index(addr)) 1177 #define pte_offset_kernel(pmd, address) pte_offset(pmd,address) 1178 #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address) 1179 #define pte_unmap(pte) do { } while (0) 1180 1181 /* 1182 * 31 bit swap entry format: 1183 * A page-table entry has some bits we have to treat in a special way. 1184 * Bits 0, 20 and bit 23 have to be zero, otherwise an specification 1185 * exception will occur instead of a page translation exception. The 1186 * specifiation exception has the bad habit not to store necessary 1187 * information in the lowcore. 1188 * Bit 21 and bit 22 are the page invalid bit and the page protection 1189 * bit. We set both to indicate a swapped page. 1190 * Bit 30 and 31 are used to distinguish the different page types. For 1191 * a swapped page these bits need to be zero. 1192 * This leaves the bits 1-19 and bits 24-29 to store type and offset. 1193 * We use the 5 bits from 25-29 for the type and the 20 bits from 1-19 1194 * plus 24 for the offset. 1195 * 0| offset |0110|o|type |00| 1196 * 0 0000000001111111111 2222 2 22222 33 1197 * 0 1234567890123456789 0123 4 56789 01 1198 * 1199 * 64 bit swap entry format: 1200 * A page-table entry has some bits we have to treat in a special way. 1201 * Bits 52 and bit 55 have to be zero, otherwise an specification 1202 * exception will occur instead of a page translation exception. The 1203 * specifiation exception has the bad habit not to store necessary 1204 * information in the lowcore. 1205 * Bit 53 and bit 54 are the page invalid bit and the page protection 1206 * bit. We set both to indicate a swapped page. 1207 * Bit 62 and 63 are used to distinguish the different page types. For 1208 * a swapped page these bits need to be zero. 1209 * This leaves the bits 0-51 and bits 56-61 to store type and offset. 1210 * We use the 5 bits from 57-61 for the type and the 53 bits from 0-51 1211 * plus 56 for the offset. 1212 * | offset |0110|o|type |00| 1213 * 0000000000111111111122222222223333333333444444444455 5555 5 55566 66 1214 * 0123456789012345678901234567890123456789012345678901 2345 6 78901 23 1215 */ 1216 #ifndef __s390x__ 1217 #define __SWP_OFFSET_MASK (~0UL >> 12) 1218 #else 1219 #define __SWP_OFFSET_MASK (~0UL >> 11) 1220 #endif 1221 static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset) 1222 { 1223 pte_t pte; 1224 offset &= __SWP_OFFSET_MASK; 1225 pte_val(pte) = _PAGE_TYPE_SWAP | ((type & 0x1f) << 2) | 1226 ((offset & 1UL) << 7) | ((offset & ~1UL) << 11); 1227 return pte; 1228 } 1229 1230 #define __swp_type(entry) (((entry).val >> 2) & 0x1f) 1231 #define __swp_offset(entry) (((entry).val >> 11) | (((entry).val >> 7) & 1)) 1232 #define __swp_entry(type,offset) ((swp_entry_t) { pte_val(mk_swap_pte((type),(offset))) }) 1233 1234 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 1235 #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) 1236 1237 #ifndef __s390x__ 1238 # define PTE_FILE_MAX_BITS 26 1239 #else /* __s390x__ */ 1240 # define PTE_FILE_MAX_BITS 59 1241 #endif /* __s390x__ */ 1242 1243 #define pte_to_pgoff(__pte) \ 1244 ((((__pte).pte >> 12) << 7) + (((__pte).pte >> 1) & 0x7f)) 1245 1246 #define pgoff_to_pte(__off) \ 1247 ((pte_t) { ((((__off) & 0x7f) << 1) + (((__off) >> 7) << 12)) \ 1248 | _PAGE_TYPE_FILE }) 1249 1250 #endif /* !__ASSEMBLY__ */ 1251 1252 #define kern_addr_valid(addr) (1) 1253 1254 extern int vmem_add_mapping(unsigned long start, unsigned long size); 1255 extern int vmem_remove_mapping(unsigned long start, unsigned long size); 1256 extern int s390_enable_sie(void); 1257 1258 /* 1259 * No page table caches to initialise 1260 */ 1261 #define pgtable_cache_init() do { } while (0) 1262 1263 #include <asm-generic/pgtable.h> 1264 1265 #endif /* _S390_PAGE_H */ 1266