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