1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * SPARC64 Huge TLB page support. 4 * 5 * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net) 6 */ 7 8 #include <linux/fs.h> 9 #include <linux/mm.h> 10 #include <linux/sched/mm.h> 11 #include <linux/hugetlb.h> 12 #include <linux/pagemap.h> 13 #include <linux/sysctl.h> 14 15 #include <asm/mman.h> 16 #include <asm/pgalloc.h> 17 #include <asm/tlb.h> 18 #include <asm/tlbflush.h> 19 #include <asm/cacheflush.h> 20 #include <asm/mmu_context.h> 21 22 /* Slightly simplified from the non-hugepage variant because by 23 * definition we don't have to worry about any page coloring stuff 24 */ 25 26 static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp, 27 unsigned long addr, 28 unsigned long len, 29 unsigned long pgoff, 30 unsigned long flags) 31 { 32 struct hstate *h = hstate_file(filp); 33 unsigned long task_size = TASK_SIZE; 34 struct vm_unmapped_area_info info; 35 36 if (test_thread_flag(TIF_32BIT)) 37 task_size = STACK_TOP32; 38 39 info.flags = 0; 40 info.length = len; 41 info.low_limit = TASK_UNMAPPED_BASE; 42 info.high_limit = min(task_size, VA_EXCLUDE_START); 43 info.align_mask = PAGE_MASK & ~huge_page_mask(h); 44 info.align_offset = 0; 45 addr = vm_unmapped_area(&info); 46 47 if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) { 48 VM_BUG_ON(addr != -ENOMEM); 49 info.low_limit = VA_EXCLUDE_END; 50 info.high_limit = task_size; 51 addr = vm_unmapped_area(&info); 52 } 53 54 return addr; 55 } 56 57 static unsigned long 58 hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, 59 const unsigned long len, 60 const unsigned long pgoff, 61 const unsigned long flags) 62 { 63 struct hstate *h = hstate_file(filp); 64 struct mm_struct *mm = current->mm; 65 unsigned long addr = addr0; 66 struct vm_unmapped_area_info info; 67 68 /* This should only ever run for 32-bit processes. */ 69 BUG_ON(!test_thread_flag(TIF_32BIT)); 70 71 info.flags = VM_UNMAPPED_AREA_TOPDOWN; 72 info.length = len; 73 info.low_limit = PAGE_SIZE; 74 info.high_limit = mm->mmap_base; 75 info.align_mask = PAGE_MASK & ~huge_page_mask(h); 76 info.align_offset = 0; 77 addr = vm_unmapped_area(&info); 78 79 /* 80 * A failed mmap() very likely causes application failure, 81 * so fall back to the bottom-up function here. This scenario 82 * can happen with large stack limits and large mmap() 83 * allocations. 84 */ 85 if (addr & ~PAGE_MASK) { 86 VM_BUG_ON(addr != -ENOMEM); 87 info.flags = 0; 88 info.low_limit = TASK_UNMAPPED_BASE; 89 info.high_limit = STACK_TOP32; 90 addr = vm_unmapped_area(&info); 91 } 92 93 return addr; 94 } 95 96 unsigned long 97 hugetlb_get_unmapped_area(struct file *file, unsigned long addr, 98 unsigned long len, unsigned long pgoff, unsigned long flags) 99 { 100 struct hstate *h = hstate_file(file); 101 struct mm_struct *mm = current->mm; 102 struct vm_area_struct *vma; 103 unsigned long task_size = TASK_SIZE; 104 105 if (test_thread_flag(TIF_32BIT)) 106 task_size = STACK_TOP32; 107 108 if (len & ~huge_page_mask(h)) 109 return -EINVAL; 110 if (len > task_size) 111 return -ENOMEM; 112 113 if (flags & MAP_FIXED) { 114 if (prepare_hugepage_range(file, addr, len)) 115 return -EINVAL; 116 return addr; 117 } 118 119 if (addr) { 120 addr = ALIGN(addr, huge_page_size(h)); 121 vma = find_vma(mm, addr); 122 if (task_size - len >= addr && 123 (!vma || addr + len <= vm_start_gap(vma))) 124 return addr; 125 } 126 if (mm->get_unmapped_area == arch_get_unmapped_area) 127 return hugetlb_get_unmapped_area_bottomup(file, addr, len, 128 pgoff, flags); 129 else 130 return hugetlb_get_unmapped_area_topdown(file, addr, len, 131 pgoff, flags); 132 } 133 134 static pte_t sun4u_hugepage_shift_to_tte(pte_t entry, unsigned int shift) 135 { 136 return entry; 137 } 138 139 static pte_t sun4v_hugepage_shift_to_tte(pte_t entry, unsigned int shift) 140 { 141 unsigned long hugepage_size = _PAGE_SZ4MB_4V; 142 143 pte_val(entry) = pte_val(entry) & ~_PAGE_SZALL_4V; 144 145 switch (shift) { 146 case HPAGE_16GB_SHIFT: 147 hugepage_size = _PAGE_SZ16GB_4V; 148 pte_val(entry) |= _PAGE_PUD_HUGE; 149 break; 150 case HPAGE_2GB_SHIFT: 151 hugepage_size = _PAGE_SZ2GB_4V; 152 pte_val(entry) |= _PAGE_PMD_HUGE; 153 break; 154 case HPAGE_256MB_SHIFT: 155 hugepage_size = _PAGE_SZ256MB_4V; 156 pte_val(entry) |= _PAGE_PMD_HUGE; 157 break; 158 case HPAGE_SHIFT: 159 pte_val(entry) |= _PAGE_PMD_HUGE; 160 break; 161 case HPAGE_64K_SHIFT: 162 hugepage_size = _PAGE_SZ64K_4V; 163 break; 164 default: 165 WARN_ONCE(1, "unsupported hugepage shift=%u\n", shift); 166 } 167 168 pte_val(entry) = pte_val(entry) | hugepage_size; 169 return entry; 170 } 171 172 static pte_t hugepage_shift_to_tte(pte_t entry, unsigned int shift) 173 { 174 if (tlb_type == hypervisor) 175 return sun4v_hugepage_shift_to_tte(entry, shift); 176 else 177 return sun4u_hugepage_shift_to_tte(entry, shift); 178 } 179 180 pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags) 181 { 182 pte_t pte; 183 184 entry = pte_mkhuge(entry); 185 pte = hugepage_shift_to_tte(entry, shift); 186 187 #ifdef CONFIG_SPARC64 188 /* If this vma has ADI enabled on it, turn on TTE.mcd 189 */ 190 if (flags & VM_SPARC_ADI) 191 return pte_mkmcd(pte); 192 else 193 return pte_mknotmcd(pte); 194 #else 195 return pte; 196 #endif 197 } 198 199 static unsigned int sun4v_huge_tte_to_shift(pte_t entry) 200 { 201 unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4V; 202 unsigned int shift; 203 204 switch (tte_szbits) { 205 case _PAGE_SZ16GB_4V: 206 shift = HPAGE_16GB_SHIFT; 207 break; 208 case _PAGE_SZ2GB_4V: 209 shift = HPAGE_2GB_SHIFT; 210 break; 211 case _PAGE_SZ256MB_4V: 212 shift = HPAGE_256MB_SHIFT; 213 break; 214 case _PAGE_SZ4MB_4V: 215 shift = REAL_HPAGE_SHIFT; 216 break; 217 case _PAGE_SZ64K_4V: 218 shift = HPAGE_64K_SHIFT; 219 break; 220 default: 221 shift = PAGE_SHIFT; 222 break; 223 } 224 return shift; 225 } 226 227 static unsigned int sun4u_huge_tte_to_shift(pte_t entry) 228 { 229 unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4U; 230 unsigned int shift; 231 232 switch (tte_szbits) { 233 case _PAGE_SZ256MB_4U: 234 shift = HPAGE_256MB_SHIFT; 235 break; 236 case _PAGE_SZ4MB_4U: 237 shift = REAL_HPAGE_SHIFT; 238 break; 239 case _PAGE_SZ64K_4U: 240 shift = HPAGE_64K_SHIFT; 241 break; 242 default: 243 shift = PAGE_SHIFT; 244 break; 245 } 246 return shift; 247 } 248 249 static unsigned long tte_to_shift(pte_t entry) 250 { 251 if (tlb_type == hypervisor) 252 return sun4v_huge_tte_to_shift(entry); 253 254 return sun4u_huge_tte_to_shift(entry); 255 } 256 257 static unsigned int huge_tte_to_shift(pte_t entry) 258 { 259 unsigned long shift = tte_to_shift(entry); 260 261 if (shift == PAGE_SHIFT) 262 WARN_ONCE(1, "tto_to_shift: invalid hugepage tte=0x%lx\n", 263 pte_val(entry)); 264 265 return shift; 266 } 267 268 static unsigned long huge_tte_to_size(pte_t pte) 269 { 270 unsigned long size = 1UL << huge_tte_to_shift(pte); 271 272 if (size == REAL_HPAGE_SIZE) 273 size = HPAGE_SIZE; 274 return size; 275 } 276 277 unsigned long pud_leaf_size(pud_t pud) { return 1UL << tte_to_shift(*(pte_t *)&pud); } 278 unsigned long pmd_leaf_size(pmd_t pmd) { return 1UL << tte_to_shift(*(pte_t *)&pmd); } 279 unsigned long pte_leaf_size(pte_t pte) { return 1UL << tte_to_shift(pte); } 280 281 pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, 282 unsigned long addr, unsigned long sz) 283 { 284 pgd_t *pgd; 285 p4d_t *p4d; 286 pud_t *pud; 287 pmd_t *pmd; 288 289 pgd = pgd_offset(mm, addr); 290 p4d = p4d_offset(pgd, addr); 291 pud = pud_alloc(mm, p4d, addr); 292 if (!pud) 293 return NULL; 294 if (sz >= PUD_SIZE) 295 return (pte_t *)pud; 296 pmd = pmd_alloc(mm, pud, addr); 297 if (!pmd) 298 return NULL; 299 if (sz >= PMD_SIZE) 300 return (pte_t *)pmd; 301 return pte_alloc_map(mm, pmd, addr); 302 } 303 304 pte_t *huge_pte_offset(struct mm_struct *mm, 305 unsigned long addr, unsigned long sz) 306 { 307 pgd_t *pgd; 308 p4d_t *p4d; 309 pud_t *pud; 310 pmd_t *pmd; 311 312 pgd = pgd_offset(mm, addr); 313 if (pgd_none(*pgd)) 314 return NULL; 315 p4d = p4d_offset(pgd, addr); 316 if (p4d_none(*p4d)) 317 return NULL; 318 pud = pud_offset(p4d, addr); 319 if (pud_none(*pud)) 320 return NULL; 321 if (is_hugetlb_pud(*pud)) 322 return (pte_t *)pud; 323 pmd = pmd_offset(pud, addr); 324 if (pmd_none(*pmd)) 325 return NULL; 326 if (is_hugetlb_pmd(*pmd)) 327 return (pte_t *)pmd; 328 return pte_offset_map(pmd, addr); 329 } 330 331 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, 332 pte_t *ptep, pte_t entry) 333 { 334 unsigned int nptes, orig_shift, shift; 335 unsigned long i, size; 336 pte_t orig; 337 338 size = huge_tte_to_size(entry); 339 340 shift = PAGE_SHIFT; 341 if (size >= PUD_SIZE) 342 shift = PUD_SHIFT; 343 else if (size >= PMD_SIZE) 344 shift = PMD_SHIFT; 345 else 346 shift = PAGE_SHIFT; 347 348 nptes = size >> shift; 349 350 if (!pte_present(*ptep) && pte_present(entry)) 351 mm->context.hugetlb_pte_count += nptes; 352 353 addr &= ~(size - 1); 354 orig = *ptep; 355 orig_shift = pte_none(orig) ? PAGE_SHIFT : huge_tte_to_shift(orig); 356 357 for (i = 0; i < nptes; i++) 358 ptep[i] = __pte(pte_val(entry) + (i << shift)); 359 360 maybe_tlb_batch_add(mm, addr, ptep, orig, 0, orig_shift); 361 /* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */ 362 if (size == HPAGE_SIZE) 363 maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, orig, 0, 364 orig_shift); 365 } 366 367 pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, 368 pte_t *ptep) 369 { 370 unsigned int i, nptes, orig_shift, shift; 371 unsigned long size; 372 pte_t entry; 373 374 entry = *ptep; 375 size = huge_tte_to_size(entry); 376 377 shift = PAGE_SHIFT; 378 if (size >= PUD_SIZE) 379 shift = PUD_SHIFT; 380 else if (size >= PMD_SIZE) 381 shift = PMD_SHIFT; 382 else 383 shift = PAGE_SHIFT; 384 385 nptes = size >> shift; 386 orig_shift = pte_none(entry) ? PAGE_SHIFT : huge_tte_to_shift(entry); 387 388 if (pte_present(entry)) 389 mm->context.hugetlb_pte_count -= nptes; 390 391 addr &= ~(size - 1); 392 for (i = 0; i < nptes; i++) 393 ptep[i] = __pte(0UL); 394 395 maybe_tlb_batch_add(mm, addr, ptep, entry, 0, orig_shift); 396 /* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */ 397 if (size == HPAGE_SIZE) 398 maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, entry, 0, 399 orig_shift); 400 401 return entry; 402 } 403 404 int pmd_huge(pmd_t pmd) 405 { 406 return !pmd_none(pmd) && 407 (pmd_val(pmd) & (_PAGE_VALID|_PAGE_PMD_HUGE)) != _PAGE_VALID; 408 } 409 410 int pud_huge(pud_t pud) 411 { 412 return !pud_none(pud) && 413 (pud_val(pud) & (_PAGE_VALID|_PAGE_PUD_HUGE)) != _PAGE_VALID; 414 } 415 416 static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd, 417 unsigned long addr) 418 { 419 pgtable_t token = pmd_pgtable(*pmd); 420 421 pmd_clear(pmd); 422 pte_free_tlb(tlb, token, addr); 423 mm_dec_nr_ptes(tlb->mm); 424 } 425 426 static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud, 427 unsigned long addr, unsigned long end, 428 unsigned long floor, unsigned long ceiling) 429 { 430 pmd_t *pmd; 431 unsigned long next; 432 unsigned long start; 433 434 start = addr; 435 pmd = pmd_offset(pud, addr); 436 do { 437 next = pmd_addr_end(addr, end); 438 if (pmd_none(*pmd)) 439 continue; 440 if (is_hugetlb_pmd(*pmd)) 441 pmd_clear(pmd); 442 else 443 hugetlb_free_pte_range(tlb, pmd, addr); 444 } while (pmd++, addr = next, addr != end); 445 446 start &= PUD_MASK; 447 if (start < floor) 448 return; 449 if (ceiling) { 450 ceiling &= PUD_MASK; 451 if (!ceiling) 452 return; 453 } 454 if (end - 1 > ceiling - 1) 455 return; 456 457 pmd = pmd_offset(pud, start); 458 pud_clear(pud); 459 pmd_free_tlb(tlb, pmd, start); 460 mm_dec_nr_pmds(tlb->mm); 461 } 462 463 static void hugetlb_free_pud_range(struct mmu_gather *tlb, p4d_t *p4d, 464 unsigned long addr, unsigned long end, 465 unsigned long floor, unsigned long ceiling) 466 { 467 pud_t *pud; 468 unsigned long next; 469 unsigned long start; 470 471 start = addr; 472 pud = pud_offset(p4d, addr); 473 do { 474 next = pud_addr_end(addr, end); 475 if (pud_none_or_clear_bad(pud)) 476 continue; 477 if (is_hugetlb_pud(*pud)) 478 pud_clear(pud); 479 else 480 hugetlb_free_pmd_range(tlb, pud, addr, next, floor, 481 ceiling); 482 } while (pud++, addr = next, addr != end); 483 484 start &= PGDIR_MASK; 485 if (start < floor) 486 return; 487 if (ceiling) { 488 ceiling &= PGDIR_MASK; 489 if (!ceiling) 490 return; 491 } 492 if (end - 1 > ceiling - 1) 493 return; 494 495 pud = pud_offset(p4d, start); 496 p4d_clear(p4d); 497 pud_free_tlb(tlb, pud, start); 498 mm_dec_nr_puds(tlb->mm); 499 } 500 501 void hugetlb_free_pgd_range(struct mmu_gather *tlb, 502 unsigned long addr, unsigned long end, 503 unsigned long floor, unsigned long ceiling) 504 { 505 pgd_t *pgd; 506 p4d_t *p4d; 507 unsigned long next; 508 509 addr &= PMD_MASK; 510 if (addr < floor) { 511 addr += PMD_SIZE; 512 if (!addr) 513 return; 514 } 515 if (ceiling) { 516 ceiling &= PMD_MASK; 517 if (!ceiling) 518 return; 519 } 520 if (end - 1 > ceiling - 1) 521 end -= PMD_SIZE; 522 if (addr > end - 1) 523 return; 524 525 pgd = pgd_offset(tlb->mm, addr); 526 p4d = p4d_offset(pgd, addr); 527 do { 528 next = p4d_addr_end(addr, end); 529 if (p4d_none_or_clear_bad(p4d)) 530 continue; 531 hugetlb_free_pud_range(tlb, p4d, addr, next, floor, ceiling); 532 } while (p4d++, addr = next, addr != end); 533 } 534