1 /* 2 * PPC Huge TLB Page Support for Kernel. 3 * 4 * Copyright (C) 2003 David Gibson, IBM Corporation. 5 * Copyright (C) 2011 Becky Bruce, Freescale Semiconductor 6 * 7 * Based on the IA-32 version: 8 * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com> 9 */ 10 11 #include <linux/mm.h> 12 #include <linux/io.h> 13 #include <linux/slab.h> 14 #include <linux/hugetlb.h> 15 #include <linux/of_fdt.h> 16 #include <linux/memblock.h> 17 #include <linux/bootmem.h> 18 #include <linux/moduleparam.h> 19 #include <asm/pgtable.h> 20 #include <asm/pgalloc.h> 21 #include <asm/tlb.h> 22 #include <asm/setup.h> 23 24 #define PAGE_SHIFT_64K 16 25 #define PAGE_SHIFT_16M 24 26 #define PAGE_SHIFT_16G 34 27 28 unsigned int HPAGE_SHIFT; 29 30 /* 31 * Tracks gpages after the device tree is scanned and before the 32 * huge_boot_pages list is ready. On non-Freescale implementations, this is 33 * just used to track 16G pages and so is a single array. FSL-based 34 * implementations may have more than one gpage size, so we need multiple 35 * arrays 36 */ 37 #ifdef CONFIG_PPC_FSL_BOOK3E 38 #define MAX_NUMBER_GPAGES 128 39 struct psize_gpages { 40 u64 gpage_list[MAX_NUMBER_GPAGES]; 41 unsigned int nr_gpages; 42 }; 43 static struct psize_gpages gpage_freearray[MMU_PAGE_COUNT]; 44 #else 45 #define MAX_NUMBER_GPAGES 1024 46 static u64 gpage_freearray[MAX_NUMBER_GPAGES]; 47 static unsigned nr_gpages; 48 #endif 49 50 static inline int shift_to_mmu_psize(unsigned int shift) 51 { 52 int psize; 53 54 for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) 55 if (mmu_psize_defs[psize].shift == shift) 56 return psize; 57 return -1; 58 } 59 60 static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize) 61 { 62 if (mmu_psize_defs[mmu_psize].shift) 63 return mmu_psize_defs[mmu_psize].shift; 64 BUG(); 65 } 66 67 #define hugepd_none(hpd) ((hpd).pd == 0) 68 69 pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea, unsigned *shift) 70 { 71 pgd_t *pg; 72 pud_t *pu; 73 pmd_t *pm; 74 hugepd_t *hpdp = NULL; 75 unsigned pdshift = PGDIR_SHIFT; 76 77 if (shift) 78 *shift = 0; 79 80 pg = pgdir + pgd_index(ea); 81 if (is_hugepd(pg)) { 82 hpdp = (hugepd_t *)pg; 83 } else if (!pgd_none(*pg)) { 84 pdshift = PUD_SHIFT; 85 pu = pud_offset(pg, ea); 86 if (is_hugepd(pu)) 87 hpdp = (hugepd_t *)pu; 88 else if (!pud_none(*pu)) { 89 pdshift = PMD_SHIFT; 90 pm = pmd_offset(pu, ea); 91 if (is_hugepd(pm)) 92 hpdp = (hugepd_t *)pm; 93 else if (!pmd_none(*pm)) { 94 return pte_offset_kernel(pm, ea); 95 } 96 } 97 } 98 99 if (!hpdp) 100 return NULL; 101 102 if (shift) 103 *shift = hugepd_shift(*hpdp); 104 return hugepte_offset(hpdp, ea, pdshift); 105 } 106 107 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) 108 { 109 return find_linux_pte_or_hugepte(mm->pgd, addr, NULL); 110 } 111 112 static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp, 113 unsigned long address, unsigned pdshift, unsigned pshift) 114 { 115 struct kmem_cache *cachep; 116 pte_t *new; 117 118 #ifdef CONFIG_PPC_FSL_BOOK3E 119 int i; 120 int num_hugepd = 1 << (pshift - pdshift); 121 cachep = hugepte_cache; 122 #else 123 cachep = PGT_CACHE(pdshift - pshift); 124 #endif 125 126 new = kmem_cache_zalloc(cachep, GFP_KERNEL|__GFP_REPEAT); 127 128 BUG_ON(pshift > HUGEPD_SHIFT_MASK); 129 BUG_ON((unsigned long)new & HUGEPD_SHIFT_MASK); 130 131 if (! new) 132 return -ENOMEM; 133 134 spin_lock(&mm->page_table_lock); 135 #ifdef CONFIG_PPC_FSL_BOOK3E 136 /* 137 * We have multiple higher-level entries that point to the same 138 * actual pte location. Fill in each as we go and backtrack on error. 139 * We need all of these so the DTLB pgtable walk code can find the 140 * right higher-level entry without knowing if it's a hugepage or not. 141 */ 142 for (i = 0; i < num_hugepd; i++, hpdp++) { 143 if (unlikely(!hugepd_none(*hpdp))) 144 break; 145 else 146 hpdp->pd = ((unsigned long)new & ~PD_HUGE) | pshift; 147 } 148 /* If we bailed from the for loop early, an error occurred, clean up */ 149 if (i < num_hugepd) { 150 for (i = i - 1 ; i >= 0; i--, hpdp--) 151 hpdp->pd = 0; 152 kmem_cache_free(cachep, new); 153 } 154 #else 155 if (!hugepd_none(*hpdp)) 156 kmem_cache_free(cachep, new); 157 else 158 hpdp->pd = ((unsigned long)new & ~PD_HUGE) | pshift; 159 #endif 160 spin_unlock(&mm->page_table_lock); 161 return 0; 162 } 163 164 /* 165 * These macros define how to determine which level of the page table holds 166 * the hpdp. 167 */ 168 #ifdef CONFIG_PPC_FSL_BOOK3E 169 #define HUGEPD_PGD_SHIFT PGDIR_SHIFT 170 #define HUGEPD_PUD_SHIFT PUD_SHIFT 171 #else 172 #define HUGEPD_PGD_SHIFT PUD_SHIFT 173 #define HUGEPD_PUD_SHIFT PMD_SHIFT 174 #endif 175 176 pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz) 177 { 178 pgd_t *pg; 179 pud_t *pu; 180 pmd_t *pm; 181 hugepd_t *hpdp = NULL; 182 unsigned pshift = __ffs(sz); 183 unsigned pdshift = PGDIR_SHIFT; 184 185 addr &= ~(sz-1); 186 187 pg = pgd_offset(mm, addr); 188 189 if (pshift >= HUGEPD_PGD_SHIFT) { 190 hpdp = (hugepd_t *)pg; 191 } else { 192 pdshift = PUD_SHIFT; 193 pu = pud_alloc(mm, pg, addr); 194 if (pshift >= HUGEPD_PUD_SHIFT) { 195 hpdp = (hugepd_t *)pu; 196 } else { 197 pdshift = PMD_SHIFT; 198 pm = pmd_alloc(mm, pu, addr); 199 hpdp = (hugepd_t *)pm; 200 } 201 } 202 203 if (!hpdp) 204 return NULL; 205 206 BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp)); 207 208 if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, pdshift, pshift)) 209 return NULL; 210 211 return hugepte_offset(hpdp, addr, pdshift); 212 } 213 214 #ifdef CONFIG_PPC_FSL_BOOK3E 215 /* Build list of addresses of gigantic pages. This function is used in early 216 * boot before the buddy or bootmem allocator is setup. 217 */ 218 void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages) 219 { 220 unsigned int idx = shift_to_mmu_psize(__ffs(page_size)); 221 int i; 222 223 if (addr == 0) 224 return; 225 226 gpage_freearray[idx].nr_gpages = number_of_pages; 227 228 for (i = 0; i < number_of_pages; i++) { 229 gpage_freearray[idx].gpage_list[i] = addr; 230 addr += page_size; 231 } 232 } 233 234 /* 235 * Moves the gigantic page addresses from the temporary list to the 236 * huge_boot_pages list. 237 */ 238 int alloc_bootmem_huge_page(struct hstate *hstate) 239 { 240 struct huge_bootmem_page *m; 241 int idx = shift_to_mmu_psize(hstate->order + PAGE_SHIFT); 242 int nr_gpages = gpage_freearray[idx].nr_gpages; 243 244 if (nr_gpages == 0) 245 return 0; 246 247 #ifdef CONFIG_HIGHMEM 248 /* 249 * If gpages can be in highmem we can't use the trick of storing the 250 * data structure in the page; allocate space for this 251 */ 252 m = alloc_bootmem(sizeof(struct huge_bootmem_page)); 253 m->phys = gpage_freearray[idx].gpage_list[--nr_gpages]; 254 #else 255 m = phys_to_virt(gpage_freearray[idx].gpage_list[--nr_gpages]); 256 #endif 257 258 list_add(&m->list, &huge_boot_pages); 259 gpage_freearray[idx].nr_gpages = nr_gpages; 260 gpage_freearray[idx].gpage_list[nr_gpages] = 0; 261 m->hstate = hstate; 262 263 return 1; 264 } 265 /* 266 * Scan the command line hugepagesz= options for gigantic pages; store those in 267 * a list that we use to allocate the memory once all options are parsed. 268 */ 269 270 unsigned long gpage_npages[MMU_PAGE_COUNT]; 271 272 static int __init do_gpage_early_setup(char *param, char *val) 273 { 274 static phys_addr_t size; 275 unsigned long npages; 276 277 /* 278 * The hugepagesz and hugepages cmdline options are interleaved. We 279 * use the size variable to keep track of whether or not this was done 280 * properly and skip over instances where it is incorrect. Other 281 * command-line parsing code will issue warnings, so we don't need to. 282 * 283 */ 284 if ((strcmp(param, "default_hugepagesz") == 0) || 285 (strcmp(param, "hugepagesz") == 0)) { 286 size = memparse(val, NULL); 287 } else if (strcmp(param, "hugepages") == 0) { 288 if (size != 0) { 289 if (sscanf(val, "%lu", &npages) <= 0) 290 npages = 0; 291 gpage_npages[shift_to_mmu_psize(__ffs(size))] = npages; 292 size = 0; 293 } 294 } 295 return 0; 296 } 297 298 299 /* 300 * This function allocates physical space for pages that are larger than the 301 * buddy allocator can handle. We want to allocate these in highmem because 302 * the amount of lowmem is limited. This means that this function MUST be 303 * called before lowmem_end_addr is set up in MMU_init() in order for the lmb 304 * allocate to grab highmem. 305 */ 306 void __init reserve_hugetlb_gpages(void) 307 { 308 static __initdata char cmdline[COMMAND_LINE_SIZE]; 309 phys_addr_t size, base; 310 int i; 311 312 strlcpy(cmdline, boot_command_line, COMMAND_LINE_SIZE); 313 parse_args("hugetlb gpages", cmdline, NULL, 0, &do_gpage_early_setup); 314 315 /* 316 * Walk gpage list in reverse, allocating larger page sizes first. 317 * Skip over unsupported sizes, or sizes that have 0 gpages allocated. 318 * When we reach the point in the list where pages are no longer 319 * considered gpages, we're done. 320 */ 321 for (i = MMU_PAGE_COUNT-1; i >= 0; i--) { 322 if (mmu_psize_defs[i].shift == 0 || gpage_npages[i] == 0) 323 continue; 324 else if (mmu_psize_to_shift(i) < (MAX_ORDER + PAGE_SHIFT)) 325 break; 326 327 size = (phys_addr_t)(1ULL << mmu_psize_to_shift(i)); 328 base = memblock_alloc_base(size * gpage_npages[i], size, 329 MEMBLOCK_ALLOC_ANYWHERE); 330 add_gpage(base, size, gpage_npages[i]); 331 } 332 } 333 334 #else /* !PPC_FSL_BOOK3E */ 335 336 /* Build list of addresses of gigantic pages. This function is used in early 337 * boot before the buddy or bootmem allocator is setup. 338 */ 339 void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages) 340 { 341 if (!addr) 342 return; 343 while (number_of_pages > 0) { 344 gpage_freearray[nr_gpages] = addr; 345 nr_gpages++; 346 number_of_pages--; 347 addr += page_size; 348 } 349 } 350 351 /* Moves the gigantic page addresses from the temporary list to the 352 * huge_boot_pages list. 353 */ 354 int alloc_bootmem_huge_page(struct hstate *hstate) 355 { 356 struct huge_bootmem_page *m; 357 if (nr_gpages == 0) 358 return 0; 359 m = phys_to_virt(gpage_freearray[--nr_gpages]); 360 gpage_freearray[nr_gpages] = 0; 361 list_add(&m->list, &huge_boot_pages); 362 m->hstate = hstate; 363 return 1; 364 } 365 #endif 366 367 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) 368 { 369 return 0; 370 } 371 372 #ifdef CONFIG_PPC_FSL_BOOK3E 373 #define HUGEPD_FREELIST_SIZE \ 374 ((PAGE_SIZE - sizeof(struct hugepd_freelist)) / sizeof(pte_t)) 375 376 struct hugepd_freelist { 377 struct rcu_head rcu; 378 unsigned int index; 379 void *ptes[0]; 380 }; 381 382 static DEFINE_PER_CPU(struct hugepd_freelist *, hugepd_freelist_cur); 383 384 static void hugepd_free_rcu_callback(struct rcu_head *head) 385 { 386 struct hugepd_freelist *batch = 387 container_of(head, struct hugepd_freelist, rcu); 388 unsigned int i; 389 390 for (i = 0; i < batch->index; i++) 391 kmem_cache_free(hugepte_cache, batch->ptes[i]); 392 393 free_page((unsigned long)batch); 394 } 395 396 static void hugepd_free(struct mmu_gather *tlb, void *hugepte) 397 { 398 struct hugepd_freelist **batchp; 399 400 batchp = &__get_cpu_var(hugepd_freelist_cur); 401 402 if (atomic_read(&tlb->mm->mm_users) < 2 || 403 cpumask_equal(mm_cpumask(tlb->mm), 404 cpumask_of(smp_processor_id()))) { 405 kmem_cache_free(hugepte_cache, hugepte); 406 return; 407 } 408 409 if (*batchp == NULL) { 410 *batchp = (struct hugepd_freelist *)__get_free_page(GFP_ATOMIC); 411 (*batchp)->index = 0; 412 } 413 414 (*batchp)->ptes[(*batchp)->index++] = hugepte; 415 if ((*batchp)->index == HUGEPD_FREELIST_SIZE) { 416 call_rcu_sched(&(*batchp)->rcu, hugepd_free_rcu_callback); 417 *batchp = NULL; 418 } 419 } 420 #endif 421 422 static void free_hugepd_range(struct mmu_gather *tlb, hugepd_t *hpdp, int pdshift, 423 unsigned long start, unsigned long end, 424 unsigned long floor, unsigned long ceiling) 425 { 426 pte_t *hugepte = hugepd_page(*hpdp); 427 int i; 428 429 unsigned long pdmask = ~((1UL << pdshift) - 1); 430 unsigned int num_hugepd = 1; 431 432 #ifdef CONFIG_PPC_FSL_BOOK3E 433 /* Note: On fsl the hpdp may be the first of several */ 434 num_hugepd = (1 << (hugepd_shift(*hpdp) - pdshift)); 435 #else 436 unsigned int shift = hugepd_shift(*hpdp); 437 #endif 438 439 start &= pdmask; 440 if (start < floor) 441 return; 442 if (ceiling) { 443 ceiling &= pdmask; 444 if (! ceiling) 445 return; 446 } 447 if (end - 1 > ceiling - 1) 448 return; 449 450 for (i = 0; i < num_hugepd; i++, hpdp++) 451 hpdp->pd = 0; 452 453 tlb->need_flush = 1; 454 455 #ifdef CONFIG_PPC_FSL_BOOK3E 456 hugepd_free(tlb, hugepte); 457 #else 458 pgtable_free_tlb(tlb, hugepte, pdshift - shift); 459 #endif 460 } 461 462 static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud, 463 unsigned long addr, unsigned long end, 464 unsigned long floor, unsigned long ceiling) 465 { 466 pmd_t *pmd; 467 unsigned long next; 468 unsigned long start; 469 470 start = addr; 471 do { 472 pmd = pmd_offset(pud, addr); 473 next = pmd_addr_end(addr, end); 474 if (pmd_none(*pmd)) 475 continue; 476 #ifdef CONFIG_PPC_FSL_BOOK3E 477 /* 478 * Increment next by the size of the huge mapping since 479 * there may be more than one entry at this level for a 480 * single hugepage, but all of them point to 481 * the same kmem cache that holds the hugepte. 482 */ 483 next = addr + (1 << hugepd_shift(*(hugepd_t *)pmd)); 484 #endif 485 free_hugepd_range(tlb, (hugepd_t *)pmd, PMD_SHIFT, 486 addr, next, floor, ceiling); 487 } while (addr = next, addr != end); 488 489 start &= PUD_MASK; 490 if (start < floor) 491 return; 492 if (ceiling) { 493 ceiling &= PUD_MASK; 494 if (!ceiling) 495 return; 496 } 497 if (end - 1 > ceiling - 1) 498 return; 499 500 pmd = pmd_offset(pud, start); 501 pud_clear(pud); 502 pmd_free_tlb(tlb, pmd, start); 503 } 504 505 static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd, 506 unsigned long addr, unsigned long end, 507 unsigned long floor, unsigned long ceiling) 508 { 509 pud_t *pud; 510 unsigned long next; 511 unsigned long start; 512 513 start = addr; 514 do { 515 pud = pud_offset(pgd, addr); 516 next = pud_addr_end(addr, end); 517 if (!is_hugepd(pud)) { 518 if (pud_none_or_clear_bad(pud)) 519 continue; 520 hugetlb_free_pmd_range(tlb, pud, addr, next, floor, 521 ceiling); 522 } else { 523 #ifdef CONFIG_PPC_FSL_BOOK3E 524 /* 525 * Increment next by the size of the huge mapping since 526 * there may be more than one entry at this level for a 527 * single hugepage, but all of them point to 528 * the same kmem cache that holds the hugepte. 529 */ 530 next = addr + (1 << hugepd_shift(*(hugepd_t *)pud)); 531 #endif 532 free_hugepd_range(tlb, (hugepd_t *)pud, PUD_SHIFT, 533 addr, next, floor, ceiling); 534 } 535 } while (addr = next, addr != end); 536 537 start &= PGDIR_MASK; 538 if (start < floor) 539 return; 540 if (ceiling) { 541 ceiling &= PGDIR_MASK; 542 if (!ceiling) 543 return; 544 } 545 if (end - 1 > ceiling - 1) 546 return; 547 548 pud = pud_offset(pgd, start); 549 pgd_clear(pgd); 550 pud_free_tlb(tlb, pud, start); 551 } 552 553 /* 554 * This function frees user-level page tables of a process. 555 * 556 * Must be called with pagetable lock held. 557 */ 558 void hugetlb_free_pgd_range(struct mmu_gather *tlb, 559 unsigned long addr, unsigned long end, 560 unsigned long floor, unsigned long ceiling) 561 { 562 pgd_t *pgd; 563 unsigned long next; 564 565 /* 566 * Because there are a number of different possible pagetable 567 * layouts for hugepage ranges, we limit knowledge of how 568 * things should be laid out to the allocation path 569 * (huge_pte_alloc(), above). Everything else works out the 570 * structure as it goes from information in the hugepd 571 * pointers. That means that we can't here use the 572 * optimization used in the normal page free_pgd_range(), of 573 * checking whether we're actually covering a large enough 574 * range to have to do anything at the top level of the walk 575 * instead of at the bottom. 576 * 577 * To make sense of this, you should probably go read the big 578 * block comment at the top of the normal free_pgd_range(), 579 * too. 580 */ 581 582 do { 583 next = pgd_addr_end(addr, end); 584 pgd = pgd_offset(tlb->mm, addr); 585 if (!is_hugepd(pgd)) { 586 if (pgd_none_or_clear_bad(pgd)) 587 continue; 588 hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling); 589 } else { 590 #ifdef CONFIG_PPC_FSL_BOOK3E 591 /* 592 * Increment next by the size of the huge mapping since 593 * there may be more than one entry at the pgd level 594 * for a single hugepage, but all of them point to the 595 * same kmem cache that holds the hugepte. 596 */ 597 next = addr + (1 << hugepd_shift(*(hugepd_t *)pgd)); 598 #endif 599 free_hugepd_range(tlb, (hugepd_t *)pgd, PGDIR_SHIFT, 600 addr, next, floor, ceiling); 601 } 602 } while (addr = next, addr != end); 603 } 604 605 struct page * 606 follow_huge_addr(struct mm_struct *mm, unsigned long address, int write) 607 { 608 pte_t *ptep; 609 struct page *page; 610 unsigned shift; 611 unsigned long mask; 612 613 ptep = find_linux_pte_or_hugepte(mm->pgd, address, &shift); 614 615 /* Verify it is a huge page else bail. */ 616 if (!ptep || !shift) 617 return ERR_PTR(-EINVAL); 618 619 mask = (1UL << shift) - 1; 620 page = pte_page(*ptep); 621 if (page) 622 page += (address & mask) / PAGE_SIZE; 623 624 return page; 625 } 626 627 int pmd_huge(pmd_t pmd) 628 { 629 return 0; 630 } 631 632 int pud_huge(pud_t pud) 633 { 634 return 0; 635 } 636 637 struct page * 638 follow_huge_pmd(struct mm_struct *mm, unsigned long address, 639 pmd_t *pmd, int write) 640 { 641 BUG(); 642 return NULL; 643 } 644 645 static noinline int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr, 646 unsigned long end, int write, struct page **pages, int *nr) 647 { 648 unsigned long mask; 649 unsigned long pte_end; 650 struct page *head, *page, *tail; 651 pte_t pte; 652 int refs; 653 654 pte_end = (addr + sz) & ~(sz-1); 655 if (pte_end < end) 656 end = pte_end; 657 658 pte = *ptep; 659 mask = _PAGE_PRESENT | _PAGE_USER; 660 if (write) 661 mask |= _PAGE_RW; 662 663 if ((pte_val(pte) & mask) != mask) 664 return 0; 665 666 /* hugepages are never "special" */ 667 VM_BUG_ON(!pfn_valid(pte_pfn(pte))); 668 669 refs = 0; 670 head = pte_page(pte); 671 672 page = head + ((addr & (sz-1)) >> PAGE_SHIFT); 673 tail = page; 674 do { 675 VM_BUG_ON(compound_head(page) != head); 676 pages[*nr] = page; 677 (*nr)++; 678 page++; 679 refs++; 680 } while (addr += PAGE_SIZE, addr != end); 681 682 if (!page_cache_add_speculative(head, refs)) { 683 *nr -= refs; 684 return 0; 685 } 686 687 if (unlikely(pte_val(pte) != pte_val(*ptep))) { 688 /* Could be optimized better */ 689 *nr -= refs; 690 while (refs--) 691 put_page(head); 692 return 0; 693 } 694 695 /* 696 * Any tail page need their mapcount reference taken before we 697 * return. 698 */ 699 while (refs--) { 700 if (PageTail(tail)) 701 get_huge_page_tail(tail); 702 tail++; 703 } 704 705 return 1; 706 } 707 708 static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end, 709 unsigned long sz) 710 { 711 unsigned long __boundary = (addr + sz) & ~(sz-1); 712 return (__boundary - 1 < end - 1) ? __boundary : end; 713 } 714 715 int gup_hugepd(hugepd_t *hugepd, unsigned pdshift, 716 unsigned long addr, unsigned long end, 717 int write, struct page **pages, int *nr) 718 { 719 pte_t *ptep; 720 unsigned long sz = 1UL << hugepd_shift(*hugepd); 721 unsigned long next; 722 723 ptep = hugepte_offset(hugepd, addr, pdshift); 724 do { 725 next = hugepte_addr_end(addr, end, sz); 726 if (!gup_hugepte(ptep, sz, addr, end, write, pages, nr)) 727 return 0; 728 } while (ptep++, addr = next, addr != end); 729 730 return 1; 731 } 732 733 #ifdef CONFIG_PPC_MM_SLICES 734 unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, 735 unsigned long len, unsigned long pgoff, 736 unsigned long flags) 737 { 738 struct hstate *hstate = hstate_file(file); 739 int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate)); 740 741 return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0); 742 } 743 #endif 744 745 unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) 746 { 747 #ifdef CONFIG_PPC_MM_SLICES 748 unsigned int psize = get_slice_psize(vma->vm_mm, vma->vm_start); 749 750 return 1UL << mmu_psize_to_shift(psize); 751 #else 752 if (!is_vm_hugetlb_page(vma)) 753 return PAGE_SIZE; 754 755 return huge_page_size(hstate_vma(vma)); 756 #endif 757 } 758 759 static inline bool is_power_of_4(unsigned long x) 760 { 761 if (is_power_of_2(x)) 762 return (__ilog2(x) % 2) ? false : true; 763 return false; 764 } 765 766 static int __init add_huge_page_size(unsigned long long size) 767 { 768 int shift = __ffs(size); 769 int mmu_psize; 770 771 /* Check that it is a page size supported by the hardware and 772 * that it fits within pagetable and slice limits. */ 773 #ifdef CONFIG_PPC_FSL_BOOK3E 774 if ((size < PAGE_SIZE) || !is_power_of_4(size)) 775 return -EINVAL; 776 #else 777 if (!is_power_of_2(size) 778 || (shift > SLICE_HIGH_SHIFT) || (shift <= PAGE_SHIFT)) 779 return -EINVAL; 780 #endif 781 782 if ((mmu_psize = shift_to_mmu_psize(shift)) < 0) 783 return -EINVAL; 784 785 #ifdef CONFIG_SPU_FS_64K_LS 786 /* Disable support for 64K huge pages when 64K SPU local store 787 * support is enabled as the current implementation conflicts. 788 */ 789 if (shift == PAGE_SHIFT_64K) 790 return -EINVAL; 791 #endif /* CONFIG_SPU_FS_64K_LS */ 792 793 BUG_ON(mmu_psize_defs[mmu_psize].shift != shift); 794 795 /* Return if huge page size has already been setup */ 796 if (size_to_hstate(size)) 797 return 0; 798 799 hugetlb_add_hstate(shift - PAGE_SHIFT); 800 801 return 0; 802 } 803 804 static int __init hugepage_setup_sz(char *str) 805 { 806 unsigned long long size; 807 808 size = memparse(str, &str); 809 810 if (add_huge_page_size(size) != 0) 811 printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size); 812 813 return 1; 814 } 815 __setup("hugepagesz=", hugepage_setup_sz); 816 817 #ifdef CONFIG_PPC_FSL_BOOK3E 818 struct kmem_cache *hugepte_cache; 819 static int __init hugetlbpage_init(void) 820 { 821 int psize; 822 823 for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { 824 unsigned shift; 825 826 if (!mmu_psize_defs[psize].shift) 827 continue; 828 829 shift = mmu_psize_to_shift(psize); 830 831 /* Don't treat normal page sizes as huge... */ 832 if (shift != PAGE_SHIFT) 833 if (add_huge_page_size(1ULL << shift) < 0) 834 continue; 835 } 836 837 /* 838 * Create a kmem cache for hugeptes. The bottom bits in the pte have 839 * size information encoded in them, so align them to allow this 840 */ 841 hugepte_cache = kmem_cache_create("hugepte-cache", sizeof(pte_t), 842 HUGEPD_SHIFT_MASK + 1, 0, NULL); 843 if (hugepte_cache == NULL) 844 panic("%s: Unable to create kmem cache for hugeptes\n", 845 __func__); 846 847 /* Default hpage size = 4M */ 848 if (mmu_psize_defs[MMU_PAGE_4M].shift) 849 HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_4M].shift; 850 else 851 panic("%s: Unable to set default huge page size\n", __func__); 852 853 854 return 0; 855 } 856 #else 857 static int __init hugetlbpage_init(void) 858 { 859 int psize; 860 861 if (!mmu_has_feature(MMU_FTR_16M_PAGE)) 862 return -ENODEV; 863 864 for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { 865 unsigned shift; 866 unsigned pdshift; 867 868 if (!mmu_psize_defs[psize].shift) 869 continue; 870 871 shift = mmu_psize_to_shift(psize); 872 873 if (add_huge_page_size(1ULL << shift) < 0) 874 continue; 875 876 if (shift < PMD_SHIFT) 877 pdshift = PMD_SHIFT; 878 else if (shift < PUD_SHIFT) 879 pdshift = PUD_SHIFT; 880 else 881 pdshift = PGDIR_SHIFT; 882 883 pgtable_cache_add(pdshift - shift, NULL); 884 if (!PGT_CACHE(pdshift - shift)) 885 panic("hugetlbpage_init(): could not create " 886 "pgtable cache for %d bit pagesize\n", shift); 887 } 888 889 /* Set default large page size. Currently, we pick 16M or 1M 890 * depending on what is available 891 */ 892 if (mmu_psize_defs[MMU_PAGE_16M].shift) 893 HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_16M].shift; 894 else if (mmu_psize_defs[MMU_PAGE_1M].shift) 895 HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_1M].shift; 896 897 return 0; 898 } 899 #endif 900 module_init(hugetlbpage_init); 901 902 void flush_dcache_icache_hugepage(struct page *page) 903 { 904 int i; 905 void *start; 906 907 BUG_ON(!PageCompound(page)); 908 909 for (i = 0; i < (1UL << compound_order(page)); i++) { 910 if (!PageHighMem(page)) { 911 __flush_dcache_icache(page_address(page+i)); 912 } else { 913 start = kmap_atomic(page+i, KM_PPC_SYNC_ICACHE); 914 __flush_dcache_icache(start); 915 kunmap_atomic(start, KM_PPC_SYNC_ICACHE); 916 } 917 } 918 } 919