1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * PowerPC64 port by Mike Corrigan and Dave Engebretsen 4 * {mikejc|engebret}@us.ibm.com 5 * 6 * Copyright (c) 2000 Mike Corrigan <mikejc@us.ibm.com> 7 * 8 * SMP scalability work: 9 * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM 10 * 11 * Module name: htab.c 12 * 13 * Description: 14 * PowerPC Hashed Page Table functions 15 */ 16 17 #undef DEBUG 18 #undef DEBUG_LOW 19 20 #define pr_fmt(fmt) "hash-mmu: " fmt 21 #include <linux/spinlock.h> 22 #include <linux/errno.h> 23 #include <linux/sched/mm.h> 24 #include <linux/proc_fs.h> 25 #include <linux/stat.h> 26 #include <linux/sysctl.h> 27 #include <linux/export.h> 28 #include <linux/ctype.h> 29 #include <linux/cache.h> 30 #include <linux/init.h> 31 #include <linux/signal.h> 32 #include <linux/memblock.h> 33 #include <linux/context_tracking.h> 34 #include <linux/libfdt.h> 35 #include <linux/pkeys.h> 36 #include <linux/hugetlb.h> 37 #include <linux/cpu.h> 38 #include <linux/pgtable.h> 39 40 #include <asm/debugfs.h> 41 #include <asm/processor.h> 42 #include <asm/mmu.h> 43 #include <asm/mmu_context.h> 44 #include <asm/page.h> 45 #include <asm/types.h> 46 #include <linux/uaccess.h> 47 #include <asm/machdep.h> 48 #include <asm/prom.h> 49 #include <asm/io.h> 50 #include <asm/eeh.h> 51 #include <asm/tlb.h> 52 #include <asm/cacheflush.h> 53 #include <asm/cputable.h> 54 #include <asm/sections.h> 55 #include <asm/copro.h> 56 #include <asm/udbg.h> 57 #include <asm/code-patching.h> 58 #include <asm/fadump.h> 59 #include <asm/firmware.h> 60 #include <asm/tm.h> 61 #include <asm/trace.h> 62 #include <asm/ps3.h> 63 #include <asm/pte-walk.h> 64 #include <asm/asm-prototypes.h> 65 #include <asm/ultravisor.h> 66 67 #include <mm/mmu_decl.h> 68 69 #include "internal.h" 70 71 72 #ifdef DEBUG 73 #define DBG(fmt...) udbg_printf(fmt) 74 #else 75 #define DBG(fmt...) 76 #endif 77 78 #ifdef DEBUG_LOW 79 #define DBG_LOW(fmt...) udbg_printf(fmt) 80 #else 81 #define DBG_LOW(fmt...) 82 #endif 83 84 #define KB (1024) 85 #define MB (1024*KB) 86 #define GB (1024L*MB) 87 88 /* 89 * Note: pte --> Linux PTE 90 * HPTE --> PowerPC Hashed Page Table Entry 91 * 92 * Execution context: 93 * htab_initialize is called with the MMU off (of course), but 94 * the kernel has been copied down to zero so it can directly 95 * reference global data. At this point it is very difficult 96 * to print debug info. 97 * 98 */ 99 100 static unsigned long _SDR1; 101 struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT]; 102 EXPORT_SYMBOL_GPL(mmu_psize_defs); 103 104 u8 hpte_page_sizes[1 << LP_BITS]; 105 EXPORT_SYMBOL_GPL(hpte_page_sizes); 106 107 struct hash_pte *htab_address; 108 unsigned long htab_size_bytes; 109 unsigned long htab_hash_mask; 110 EXPORT_SYMBOL_GPL(htab_hash_mask); 111 int mmu_linear_psize = MMU_PAGE_4K; 112 EXPORT_SYMBOL_GPL(mmu_linear_psize); 113 int mmu_virtual_psize = MMU_PAGE_4K; 114 int mmu_vmalloc_psize = MMU_PAGE_4K; 115 #ifdef CONFIG_SPARSEMEM_VMEMMAP 116 int mmu_vmemmap_psize = MMU_PAGE_4K; 117 #endif 118 int mmu_io_psize = MMU_PAGE_4K; 119 int mmu_kernel_ssize = MMU_SEGSIZE_256M; 120 EXPORT_SYMBOL_GPL(mmu_kernel_ssize); 121 int mmu_highuser_ssize = MMU_SEGSIZE_256M; 122 u16 mmu_slb_size = 64; 123 EXPORT_SYMBOL_GPL(mmu_slb_size); 124 #ifdef CONFIG_PPC_64K_PAGES 125 int mmu_ci_restrictions; 126 #endif 127 #ifdef CONFIG_DEBUG_PAGEALLOC 128 static u8 *linear_map_hash_slots; 129 static unsigned long linear_map_hash_count; 130 static DEFINE_SPINLOCK(linear_map_hash_lock); 131 #endif /* CONFIG_DEBUG_PAGEALLOC */ 132 struct mmu_hash_ops mmu_hash_ops; 133 EXPORT_SYMBOL(mmu_hash_ops); 134 135 /* 136 * These are definitions of page sizes arrays to be used when none 137 * is provided by the firmware. 138 */ 139 140 /* 141 * Fallback (4k pages only) 142 */ 143 static struct mmu_psize_def mmu_psize_defaults[] = { 144 [MMU_PAGE_4K] = { 145 .shift = 12, 146 .sllp = 0, 147 .penc = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1}, 148 .avpnm = 0, 149 .tlbiel = 0, 150 }, 151 }; 152 153 /* 154 * POWER4, GPUL, POWER5 155 * 156 * Support for 16Mb large pages 157 */ 158 static struct mmu_psize_def mmu_psize_defaults_gp[] = { 159 [MMU_PAGE_4K] = { 160 .shift = 12, 161 .sllp = 0, 162 .penc = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1}, 163 .avpnm = 0, 164 .tlbiel = 1, 165 }, 166 [MMU_PAGE_16M] = { 167 .shift = 24, 168 .sllp = SLB_VSID_L, 169 .penc = {[0 ... MMU_PAGE_16M - 1] = -1, [MMU_PAGE_16M] = 0, 170 [MMU_PAGE_16M + 1 ... MMU_PAGE_COUNT - 1] = -1 }, 171 .avpnm = 0x1UL, 172 .tlbiel = 0, 173 }, 174 }; 175 176 /* 177 * 'R' and 'C' update notes: 178 * - Under pHyp or KVM, the updatepp path will not set C, thus it *will* 179 * create writeable HPTEs without C set, because the hcall H_PROTECT 180 * that we use in that case will not update C 181 * - The above is however not a problem, because we also don't do that 182 * fancy "no flush" variant of eviction and we use H_REMOVE which will 183 * do the right thing and thus we don't have the race I described earlier 184 * 185 * - Under bare metal, we do have the race, so we need R and C set 186 * - We make sure R is always set and never lost 187 * - C is _PAGE_DIRTY, and *should* always be set for a writeable mapping 188 */ 189 unsigned long htab_convert_pte_flags(unsigned long pteflags) 190 { 191 unsigned long rflags = 0; 192 193 /* _PAGE_EXEC -> NOEXEC */ 194 if ((pteflags & _PAGE_EXEC) == 0) 195 rflags |= HPTE_R_N; 196 /* 197 * PPP bits: 198 * Linux uses slb key 0 for kernel and 1 for user. 199 * kernel RW areas are mapped with PPP=0b000 200 * User area is mapped with PPP=0b010 for read/write 201 * or PPP=0b011 for read-only (including writeable but clean pages). 202 */ 203 if (pteflags & _PAGE_PRIVILEGED) { 204 /* 205 * Kernel read only mapped with ppp bits 0b110 206 */ 207 if (!(pteflags & _PAGE_WRITE)) { 208 if (mmu_has_feature(MMU_FTR_KERNEL_RO)) 209 rflags |= (HPTE_R_PP0 | 0x2); 210 else 211 rflags |= 0x3; 212 } 213 } else { 214 if (pteflags & _PAGE_RWX) 215 rflags |= 0x2; 216 if (!((pteflags & _PAGE_WRITE) && (pteflags & _PAGE_DIRTY))) 217 rflags |= 0x1; 218 } 219 /* 220 * We can't allow hardware to update hpte bits. Hence always 221 * set 'R' bit and set 'C' if it is a write fault 222 */ 223 rflags |= HPTE_R_R; 224 225 if (pteflags & _PAGE_DIRTY) 226 rflags |= HPTE_R_C; 227 /* 228 * Add in WIG bits 229 */ 230 231 if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_TOLERANT) 232 rflags |= HPTE_R_I; 233 else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_NON_IDEMPOTENT) 234 rflags |= (HPTE_R_I | HPTE_R_G); 235 else 236 /* 237 * Add memory coherence if cache inhibited is not set 238 */ 239 rflags |= HPTE_R_M; 240 241 rflags |= pte_to_hpte_pkey_bits(pteflags); 242 return rflags; 243 } 244 245 int htab_bolt_mapping(unsigned long vstart, unsigned long vend, 246 unsigned long pstart, unsigned long prot, 247 int psize, int ssize) 248 { 249 unsigned long vaddr, paddr; 250 unsigned int step, shift; 251 int ret = 0; 252 253 shift = mmu_psize_defs[psize].shift; 254 step = 1 << shift; 255 256 prot = htab_convert_pte_flags(prot); 257 258 DBG("htab_bolt_mapping(%lx..%lx -> %lx (%lx,%d,%d)\n", 259 vstart, vend, pstart, prot, psize, ssize); 260 261 for (vaddr = vstart, paddr = pstart; vaddr < vend; 262 vaddr += step, paddr += step) { 263 unsigned long hash, hpteg; 264 unsigned long vsid = get_kernel_vsid(vaddr, ssize); 265 unsigned long vpn = hpt_vpn(vaddr, vsid, ssize); 266 unsigned long tprot = prot; 267 bool secondary_hash = false; 268 269 /* 270 * If we hit a bad address return error. 271 */ 272 if (!vsid) 273 return -1; 274 /* Make kernel text executable */ 275 if (overlaps_kernel_text(vaddr, vaddr + step)) 276 tprot &= ~HPTE_R_N; 277 278 /* 279 * If relocatable, check if it overlaps interrupt vectors that 280 * are copied down to real 0. For relocatable kernel 281 * (e.g. kdump case) we copy interrupt vectors down to real 282 * address 0. Mark that region as executable. This is 283 * because on p8 system with relocation on exception feature 284 * enabled, exceptions are raised with MMU (IR=DR=1) ON. Hence 285 * in order to execute the interrupt handlers in virtual 286 * mode the vector region need to be marked as executable. 287 */ 288 if ((PHYSICAL_START > MEMORY_START) && 289 overlaps_interrupt_vector_text(vaddr, vaddr + step)) 290 tprot &= ~HPTE_R_N; 291 292 hash = hpt_hash(vpn, shift, ssize); 293 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 294 295 BUG_ON(!mmu_hash_ops.hpte_insert); 296 repeat: 297 ret = mmu_hash_ops.hpte_insert(hpteg, vpn, paddr, tprot, 298 HPTE_V_BOLTED, psize, psize, 299 ssize); 300 if (ret == -1) { 301 /* 302 * Try to to keep bolted entries in primary. 303 * Remove non bolted entries and try insert again 304 */ 305 ret = mmu_hash_ops.hpte_remove(hpteg); 306 if (ret != -1) 307 ret = mmu_hash_ops.hpte_insert(hpteg, vpn, paddr, tprot, 308 HPTE_V_BOLTED, psize, psize, 309 ssize); 310 if (ret == -1 && !secondary_hash) { 311 secondary_hash = true; 312 hpteg = ((~hash & htab_hash_mask) * HPTES_PER_GROUP); 313 goto repeat; 314 } 315 } 316 317 if (ret < 0) 318 break; 319 320 cond_resched(); 321 #ifdef CONFIG_DEBUG_PAGEALLOC 322 if (debug_pagealloc_enabled() && 323 (paddr >> PAGE_SHIFT) < linear_map_hash_count) 324 linear_map_hash_slots[paddr >> PAGE_SHIFT] = ret | 0x80; 325 #endif /* CONFIG_DEBUG_PAGEALLOC */ 326 } 327 return ret < 0 ? ret : 0; 328 } 329 330 int htab_remove_mapping(unsigned long vstart, unsigned long vend, 331 int psize, int ssize) 332 { 333 unsigned long vaddr; 334 unsigned int step, shift; 335 int rc; 336 int ret = 0; 337 338 shift = mmu_psize_defs[psize].shift; 339 step = 1 << shift; 340 341 if (!mmu_hash_ops.hpte_removebolted) 342 return -ENODEV; 343 344 for (vaddr = vstart; vaddr < vend; vaddr += step) { 345 rc = mmu_hash_ops.hpte_removebolted(vaddr, psize, ssize); 346 if (rc == -ENOENT) { 347 ret = -ENOENT; 348 continue; 349 } 350 if (rc < 0) 351 return rc; 352 } 353 354 return ret; 355 } 356 357 static bool disable_1tb_segments = false; 358 359 static int __init parse_disable_1tb_segments(char *p) 360 { 361 disable_1tb_segments = true; 362 return 0; 363 } 364 early_param("disable_1tb_segments", parse_disable_1tb_segments); 365 366 static int __init htab_dt_scan_seg_sizes(unsigned long node, 367 const char *uname, int depth, 368 void *data) 369 { 370 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 371 const __be32 *prop; 372 int size = 0; 373 374 /* We are scanning "cpu" nodes only */ 375 if (type == NULL || strcmp(type, "cpu") != 0) 376 return 0; 377 378 prop = of_get_flat_dt_prop(node, "ibm,processor-segment-sizes", &size); 379 if (prop == NULL) 380 return 0; 381 for (; size >= 4; size -= 4, ++prop) { 382 if (be32_to_cpu(prop[0]) == 40) { 383 DBG("1T segment support detected\n"); 384 385 if (disable_1tb_segments) { 386 DBG("1T segments disabled by command line\n"); 387 break; 388 } 389 390 cur_cpu_spec->mmu_features |= MMU_FTR_1T_SEGMENT; 391 return 1; 392 } 393 } 394 cur_cpu_spec->mmu_features &= ~MMU_FTR_NO_SLBIE_B; 395 return 0; 396 } 397 398 static int __init get_idx_from_shift(unsigned int shift) 399 { 400 int idx = -1; 401 402 switch (shift) { 403 case 0xc: 404 idx = MMU_PAGE_4K; 405 break; 406 case 0x10: 407 idx = MMU_PAGE_64K; 408 break; 409 case 0x14: 410 idx = MMU_PAGE_1M; 411 break; 412 case 0x18: 413 idx = MMU_PAGE_16M; 414 break; 415 case 0x22: 416 idx = MMU_PAGE_16G; 417 break; 418 } 419 return idx; 420 } 421 422 static int __init htab_dt_scan_page_sizes(unsigned long node, 423 const char *uname, int depth, 424 void *data) 425 { 426 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 427 const __be32 *prop; 428 int size = 0; 429 430 /* We are scanning "cpu" nodes only */ 431 if (type == NULL || strcmp(type, "cpu") != 0) 432 return 0; 433 434 prop = of_get_flat_dt_prop(node, "ibm,segment-page-sizes", &size); 435 if (!prop) 436 return 0; 437 438 pr_info("Page sizes from device-tree:\n"); 439 size /= 4; 440 cur_cpu_spec->mmu_features &= ~(MMU_FTR_16M_PAGE); 441 while(size > 0) { 442 unsigned int base_shift = be32_to_cpu(prop[0]); 443 unsigned int slbenc = be32_to_cpu(prop[1]); 444 unsigned int lpnum = be32_to_cpu(prop[2]); 445 struct mmu_psize_def *def; 446 int idx, base_idx; 447 448 size -= 3; prop += 3; 449 base_idx = get_idx_from_shift(base_shift); 450 if (base_idx < 0) { 451 /* skip the pte encoding also */ 452 prop += lpnum * 2; size -= lpnum * 2; 453 continue; 454 } 455 def = &mmu_psize_defs[base_idx]; 456 if (base_idx == MMU_PAGE_16M) 457 cur_cpu_spec->mmu_features |= MMU_FTR_16M_PAGE; 458 459 def->shift = base_shift; 460 if (base_shift <= 23) 461 def->avpnm = 0; 462 else 463 def->avpnm = (1 << (base_shift - 23)) - 1; 464 def->sllp = slbenc; 465 /* 466 * We don't know for sure what's up with tlbiel, so 467 * for now we only set it for 4K and 64K pages 468 */ 469 if (base_idx == MMU_PAGE_4K || base_idx == MMU_PAGE_64K) 470 def->tlbiel = 1; 471 else 472 def->tlbiel = 0; 473 474 while (size > 0 && lpnum) { 475 unsigned int shift = be32_to_cpu(prop[0]); 476 int penc = be32_to_cpu(prop[1]); 477 478 prop += 2; size -= 2; 479 lpnum--; 480 481 idx = get_idx_from_shift(shift); 482 if (idx < 0) 483 continue; 484 485 if (penc == -1) 486 pr_err("Invalid penc for base_shift=%d " 487 "shift=%d\n", base_shift, shift); 488 489 def->penc[idx] = penc; 490 pr_info("base_shift=%d: shift=%d, sllp=0x%04lx," 491 " avpnm=0x%08lx, tlbiel=%d, penc=%d\n", 492 base_shift, shift, def->sllp, 493 def->avpnm, def->tlbiel, def->penc[idx]); 494 } 495 } 496 497 return 1; 498 } 499 500 #ifdef CONFIG_HUGETLB_PAGE 501 /* 502 * Scan for 16G memory blocks that have been set aside for huge pages 503 * and reserve those blocks for 16G huge pages. 504 */ 505 static int __init htab_dt_scan_hugepage_blocks(unsigned long node, 506 const char *uname, int depth, 507 void *data) { 508 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 509 const __be64 *addr_prop; 510 const __be32 *page_count_prop; 511 unsigned int expected_pages; 512 long unsigned int phys_addr; 513 long unsigned int block_size; 514 515 /* We are scanning "memory" nodes only */ 516 if (type == NULL || strcmp(type, "memory") != 0) 517 return 0; 518 519 /* 520 * This property is the log base 2 of the number of virtual pages that 521 * will represent this memory block. 522 */ 523 page_count_prop = of_get_flat_dt_prop(node, "ibm,expected#pages", NULL); 524 if (page_count_prop == NULL) 525 return 0; 526 expected_pages = (1 << be32_to_cpu(page_count_prop[0])); 527 addr_prop = of_get_flat_dt_prop(node, "reg", NULL); 528 if (addr_prop == NULL) 529 return 0; 530 phys_addr = be64_to_cpu(addr_prop[0]); 531 block_size = be64_to_cpu(addr_prop[1]); 532 if (block_size != (16 * GB)) 533 return 0; 534 printk(KERN_INFO "Huge page(16GB) memory: " 535 "addr = 0x%lX size = 0x%lX pages = %d\n", 536 phys_addr, block_size, expected_pages); 537 if (phys_addr + block_size * expected_pages <= memblock_end_of_DRAM()) { 538 memblock_reserve(phys_addr, block_size * expected_pages); 539 pseries_add_gpage(phys_addr, block_size, expected_pages); 540 } 541 return 0; 542 } 543 #endif /* CONFIG_HUGETLB_PAGE */ 544 545 static void mmu_psize_set_default_penc(void) 546 { 547 int bpsize, apsize; 548 for (bpsize = 0; bpsize < MMU_PAGE_COUNT; bpsize++) 549 for (apsize = 0; apsize < MMU_PAGE_COUNT; apsize++) 550 mmu_psize_defs[bpsize].penc[apsize] = -1; 551 } 552 553 #ifdef CONFIG_PPC_64K_PAGES 554 555 static bool might_have_hea(void) 556 { 557 /* 558 * The HEA ethernet adapter requires awareness of the 559 * GX bus. Without that awareness we can easily assume 560 * we will never see an HEA ethernet device. 561 */ 562 #ifdef CONFIG_IBMEBUS 563 return !cpu_has_feature(CPU_FTR_ARCH_207S) && 564 firmware_has_feature(FW_FEATURE_SPLPAR); 565 #else 566 return false; 567 #endif 568 } 569 570 #endif /* #ifdef CONFIG_PPC_64K_PAGES */ 571 572 static void __init htab_scan_page_sizes(void) 573 { 574 int rc; 575 576 /* se the invalid penc to -1 */ 577 mmu_psize_set_default_penc(); 578 579 /* Default to 4K pages only */ 580 memcpy(mmu_psize_defs, mmu_psize_defaults, 581 sizeof(mmu_psize_defaults)); 582 583 /* 584 * Try to find the available page sizes in the device-tree 585 */ 586 rc = of_scan_flat_dt(htab_dt_scan_page_sizes, NULL); 587 if (rc == 0 && early_mmu_has_feature(MMU_FTR_16M_PAGE)) { 588 /* 589 * Nothing in the device-tree, but the CPU supports 16M pages, 590 * so let's fallback on a known size list for 16M capable CPUs. 591 */ 592 memcpy(mmu_psize_defs, mmu_psize_defaults_gp, 593 sizeof(mmu_psize_defaults_gp)); 594 } 595 596 #ifdef CONFIG_HUGETLB_PAGE 597 if (!hugetlb_disabled && !early_radix_enabled() ) { 598 /* Reserve 16G huge page memory sections for huge pages */ 599 of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL); 600 } 601 #endif /* CONFIG_HUGETLB_PAGE */ 602 } 603 604 /* 605 * Fill in the hpte_page_sizes[] array. 606 * We go through the mmu_psize_defs[] array looking for all the 607 * supported base/actual page size combinations. Each combination 608 * has a unique pagesize encoding (penc) value in the low bits of 609 * the LP field of the HPTE. For actual page sizes less than 1MB, 610 * some of the upper LP bits are used for RPN bits, meaning that 611 * we need to fill in several entries in hpte_page_sizes[]. 612 * 613 * In diagrammatic form, with r = RPN bits and z = page size bits: 614 * PTE LP actual page size 615 * rrrr rrrz >=8KB 616 * rrrr rrzz >=16KB 617 * rrrr rzzz >=32KB 618 * rrrr zzzz >=64KB 619 * ... 620 * 621 * The zzzz bits are implementation-specific but are chosen so that 622 * no encoding for a larger page size uses the same value in its 623 * low-order N bits as the encoding for the 2^(12+N) byte page size 624 * (if it exists). 625 */ 626 static void init_hpte_page_sizes(void) 627 { 628 long int ap, bp; 629 long int shift, penc; 630 631 for (bp = 0; bp < MMU_PAGE_COUNT; ++bp) { 632 if (!mmu_psize_defs[bp].shift) 633 continue; /* not a supported page size */ 634 for (ap = bp; ap < MMU_PAGE_COUNT; ++ap) { 635 penc = mmu_psize_defs[bp].penc[ap]; 636 if (penc == -1 || !mmu_psize_defs[ap].shift) 637 continue; 638 shift = mmu_psize_defs[ap].shift - LP_SHIFT; 639 if (shift <= 0) 640 continue; /* should never happen */ 641 /* 642 * For page sizes less than 1MB, this loop 643 * replicates the entry for all possible values 644 * of the rrrr bits. 645 */ 646 while (penc < (1 << LP_BITS)) { 647 hpte_page_sizes[penc] = (ap << 4) | bp; 648 penc += 1 << shift; 649 } 650 } 651 } 652 } 653 654 static void __init htab_init_page_sizes(void) 655 { 656 bool aligned = true; 657 init_hpte_page_sizes(); 658 659 if (!debug_pagealloc_enabled()) { 660 /* 661 * Pick a size for the linear mapping. Currently, we only 662 * support 16M, 1M and 4K which is the default 663 */ 664 if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && 665 (unsigned long)_stext % 0x1000000) { 666 if (mmu_psize_defs[MMU_PAGE_16M].shift) 667 pr_warn("Kernel not 16M aligned, disabling 16M linear map alignment\n"); 668 aligned = false; 669 } 670 671 if (mmu_psize_defs[MMU_PAGE_16M].shift && aligned) 672 mmu_linear_psize = MMU_PAGE_16M; 673 else if (mmu_psize_defs[MMU_PAGE_1M].shift) 674 mmu_linear_psize = MMU_PAGE_1M; 675 } 676 677 #ifdef CONFIG_PPC_64K_PAGES 678 /* 679 * Pick a size for the ordinary pages. Default is 4K, we support 680 * 64K for user mappings and vmalloc if supported by the processor. 681 * We only use 64k for ioremap if the processor 682 * (and firmware) support cache-inhibited large pages. 683 * If not, we use 4k and set mmu_ci_restrictions so that 684 * hash_page knows to switch processes that use cache-inhibited 685 * mappings to 4k pages. 686 */ 687 if (mmu_psize_defs[MMU_PAGE_64K].shift) { 688 mmu_virtual_psize = MMU_PAGE_64K; 689 mmu_vmalloc_psize = MMU_PAGE_64K; 690 if (mmu_linear_psize == MMU_PAGE_4K) 691 mmu_linear_psize = MMU_PAGE_64K; 692 if (mmu_has_feature(MMU_FTR_CI_LARGE_PAGE)) { 693 /* 694 * When running on pSeries using 64k pages for ioremap 695 * would stop us accessing the HEA ethernet. So if we 696 * have the chance of ever seeing one, stay at 4k. 697 */ 698 if (!might_have_hea()) 699 mmu_io_psize = MMU_PAGE_64K; 700 } else 701 mmu_ci_restrictions = 1; 702 } 703 #endif /* CONFIG_PPC_64K_PAGES */ 704 705 #ifdef CONFIG_SPARSEMEM_VMEMMAP 706 /* 707 * We try to use 16M pages for vmemmap if that is supported 708 * and we have at least 1G of RAM at boot 709 */ 710 if (mmu_psize_defs[MMU_PAGE_16M].shift && 711 memblock_phys_mem_size() >= 0x40000000) 712 mmu_vmemmap_psize = MMU_PAGE_16M; 713 else 714 mmu_vmemmap_psize = mmu_virtual_psize; 715 #endif /* CONFIG_SPARSEMEM_VMEMMAP */ 716 717 printk(KERN_DEBUG "Page orders: linear mapping = %d, " 718 "virtual = %d, io = %d" 719 #ifdef CONFIG_SPARSEMEM_VMEMMAP 720 ", vmemmap = %d" 721 #endif 722 "\n", 723 mmu_psize_defs[mmu_linear_psize].shift, 724 mmu_psize_defs[mmu_virtual_psize].shift, 725 mmu_psize_defs[mmu_io_psize].shift 726 #ifdef CONFIG_SPARSEMEM_VMEMMAP 727 ,mmu_psize_defs[mmu_vmemmap_psize].shift 728 #endif 729 ); 730 } 731 732 static int __init htab_dt_scan_pftsize(unsigned long node, 733 const char *uname, int depth, 734 void *data) 735 { 736 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 737 const __be32 *prop; 738 739 /* We are scanning "cpu" nodes only */ 740 if (type == NULL || strcmp(type, "cpu") != 0) 741 return 0; 742 743 prop = of_get_flat_dt_prop(node, "ibm,pft-size", NULL); 744 if (prop != NULL) { 745 /* pft_size[0] is the NUMA CEC cookie */ 746 ppc64_pft_size = be32_to_cpu(prop[1]); 747 return 1; 748 } 749 return 0; 750 } 751 752 unsigned htab_shift_for_mem_size(unsigned long mem_size) 753 { 754 unsigned memshift = __ilog2(mem_size); 755 unsigned pshift = mmu_psize_defs[mmu_virtual_psize].shift; 756 unsigned pteg_shift; 757 758 /* round mem_size up to next power of 2 */ 759 if ((1UL << memshift) < mem_size) 760 memshift += 1; 761 762 /* aim for 2 pages / pteg */ 763 pteg_shift = memshift - (pshift + 1); 764 765 /* 766 * 2^11 PTEGS of 128 bytes each, ie. 2^18 bytes is the minimum htab 767 * size permitted by the architecture. 768 */ 769 return max(pteg_shift + 7, 18U); 770 } 771 772 static unsigned long __init htab_get_table_size(void) 773 { 774 /* 775 * If hash size isn't already provided by the platform, we try to 776 * retrieve it from the device-tree. If it's not there neither, we 777 * calculate it now based on the total RAM size 778 */ 779 if (ppc64_pft_size == 0) 780 of_scan_flat_dt(htab_dt_scan_pftsize, NULL); 781 if (ppc64_pft_size) 782 return 1UL << ppc64_pft_size; 783 784 return 1UL << htab_shift_for_mem_size(memblock_phys_mem_size()); 785 } 786 787 #ifdef CONFIG_MEMORY_HOTPLUG 788 static int resize_hpt_for_hotplug(unsigned long new_mem_size) 789 { 790 unsigned target_hpt_shift; 791 792 if (!mmu_hash_ops.resize_hpt) 793 return 0; 794 795 target_hpt_shift = htab_shift_for_mem_size(new_mem_size); 796 797 /* 798 * To avoid lots of HPT resizes if memory size is fluctuating 799 * across a boundary, we deliberately have some hysterisis 800 * here: we immediately increase the HPT size if the target 801 * shift exceeds the current shift, but we won't attempt to 802 * reduce unless the target shift is at least 2 below the 803 * current shift 804 */ 805 if (target_hpt_shift > ppc64_pft_size || 806 target_hpt_shift < ppc64_pft_size - 1) 807 return mmu_hash_ops.resize_hpt(target_hpt_shift); 808 809 return 0; 810 } 811 812 int hash__create_section_mapping(unsigned long start, unsigned long end, 813 int nid, pgprot_t prot) 814 { 815 int rc; 816 817 if (end >= H_VMALLOC_START) { 818 pr_warn("Outside the supported range\n"); 819 return -1; 820 } 821 822 resize_hpt_for_hotplug(memblock_phys_mem_size()); 823 824 rc = htab_bolt_mapping(start, end, __pa(start), 825 pgprot_val(prot), mmu_linear_psize, 826 mmu_kernel_ssize); 827 828 if (rc < 0) { 829 int rc2 = htab_remove_mapping(start, end, mmu_linear_psize, 830 mmu_kernel_ssize); 831 BUG_ON(rc2 && (rc2 != -ENOENT)); 832 } 833 return rc; 834 } 835 836 int hash__remove_section_mapping(unsigned long start, unsigned long end) 837 { 838 int rc = htab_remove_mapping(start, end, mmu_linear_psize, 839 mmu_kernel_ssize); 840 WARN_ON(rc < 0); 841 842 if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC) 843 pr_warn("Hash collision while resizing HPT\n"); 844 845 return rc; 846 } 847 #endif /* CONFIG_MEMORY_HOTPLUG */ 848 849 static void __init hash_init_partition_table(phys_addr_t hash_table, 850 unsigned long htab_size) 851 { 852 mmu_partition_table_init(); 853 854 /* 855 * PS field (VRMA page size) is not used for LPID 0, hence set to 0. 856 * For now, UPRT is 0 and we have no segment table. 857 */ 858 htab_size = __ilog2(htab_size) - 18; 859 mmu_partition_table_set_entry(0, hash_table | htab_size, 0, false); 860 pr_info("Partition table %p\n", partition_tb); 861 } 862 863 static void __init htab_initialize(void) 864 { 865 unsigned long table; 866 unsigned long pteg_count; 867 unsigned long prot; 868 unsigned long base = 0, size = 0; 869 struct memblock_region *reg; 870 871 DBG(" -> htab_initialize()\n"); 872 873 if (mmu_has_feature(MMU_FTR_1T_SEGMENT)) { 874 mmu_kernel_ssize = MMU_SEGSIZE_1T; 875 mmu_highuser_ssize = MMU_SEGSIZE_1T; 876 printk(KERN_INFO "Using 1TB segments\n"); 877 } 878 879 if (stress_slb_enabled) 880 static_branch_enable(&stress_slb_key); 881 882 /* 883 * Calculate the required size of the htab. We want the number of 884 * PTEGs to equal one half the number of real pages. 885 */ 886 htab_size_bytes = htab_get_table_size(); 887 pteg_count = htab_size_bytes >> 7; 888 889 htab_hash_mask = pteg_count - 1; 890 891 if (firmware_has_feature(FW_FEATURE_LPAR) || 892 firmware_has_feature(FW_FEATURE_PS3_LV1)) { 893 /* Using a hypervisor which owns the htab */ 894 htab_address = NULL; 895 _SDR1 = 0; 896 #ifdef CONFIG_FA_DUMP 897 /* 898 * If firmware assisted dump is active firmware preserves 899 * the contents of htab along with entire partition memory. 900 * Clear the htab if firmware assisted dump is active so 901 * that we dont end up using old mappings. 902 */ 903 if (is_fadump_active() && mmu_hash_ops.hpte_clear_all) 904 mmu_hash_ops.hpte_clear_all(); 905 #endif 906 } else { 907 unsigned long limit = MEMBLOCK_ALLOC_ANYWHERE; 908 909 #ifdef CONFIG_PPC_CELL 910 /* 911 * Cell may require the hash table down low when using the 912 * Axon IOMMU in order to fit the dynamic region over it, see 913 * comments in cell/iommu.c 914 */ 915 if (fdt_subnode_offset(initial_boot_params, 0, "axon") > 0) { 916 limit = 0x80000000; 917 pr_info("Hash table forced below 2G for Axon IOMMU\n"); 918 } 919 #endif /* CONFIG_PPC_CELL */ 920 921 table = memblock_phys_alloc_range(htab_size_bytes, 922 htab_size_bytes, 923 0, limit); 924 if (!table) 925 panic("ERROR: Failed to allocate %pa bytes below %pa\n", 926 &htab_size_bytes, &limit); 927 928 DBG("Hash table allocated at %lx, size: %lx\n", table, 929 htab_size_bytes); 930 931 htab_address = __va(table); 932 933 /* htab absolute addr + encoded htabsize */ 934 _SDR1 = table + __ilog2(htab_size_bytes) - 18; 935 936 /* Initialize the HPT with no entries */ 937 memset((void *)table, 0, htab_size_bytes); 938 939 if (!cpu_has_feature(CPU_FTR_ARCH_300)) 940 /* Set SDR1 */ 941 mtspr(SPRN_SDR1, _SDR1); 942 else 943 hash_init_partition_table(table, htab_size_bytes); 944 } 945 946 prot = pgprot_val(PAGE_KERNEL); 947 948 #ifdef CONFIG_DEBUG_PAGEALLOC 949 if (debug_pagealloc_enabled()) { 950 linear_map_hash_count = memblock_end_of_DRAM() >> PAGE_SHIFT; 951 linear_map_hash_slots = memblock_alloc_try_nid( 952 linear_map_hash_count, 1, MEMBLOCK_LOW_LIMIT, 953 ppc64_rma_size, NUMA_NO_NODE); 954 if (!linear_map_hash_slots) 955 panic("%s: Failed to allocate %lu bytes max_addr=%pa\n", 956 __func__, linear_map_hash_count, &ppc64_rma_size); 957 } 958 #endif /* CONFIG_DEBUG_PAGEALLOC */ 959 960 /* create bolted the linear mapping in the hash table */ 961 for_each_memblock(memory, reg) { 962 base = (unsigned long)__va(reg->base); 963 size = reg->size; 964 965 DBG("creating mapping for region: %lx..%lx (prot: %lx)\n", 966 base, size, prot); 967 968 if ((base + size) >= H_VMALLOC_START) { 969 pr_warn("Outside the supported range\n"); 970 continue; 971 } 972 973 BUG_ON(htab_bolt_mapping(base, base + size, __pa(base), 974 prot, mmu_linear_psize, mmu_kernel_ssize)); 975 } 976 memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE); 977 978 /* 979 * If we have a memory_limit and we've allocated TCEs then we need to 980 * explicitly map the TCE area at the top of RAM. We also cope with the 981 * case that the TCEs start below memory_limit. 982 * tce_alloc_start/end are 16MB aligned so the mapping should work 983 * for either 4K or 16MB pages. 984 */ 985 if (tce_alloc_start) { 986 tce_alloc_start = (unsigned long)__va(tce_alloc_start); 987 tce_alloc_end = (unsigned long)__va(tce_alloc_end); 988 989 if (base + size >= tce_alloc_start) 990 tce_alloc_start = base + size + 1; 991 992 BUG_ON(htab_bolt_mapping(tce_alloc_start, tce_alloc_end, 993 __pa(tce_alloc_start), prot, 994 mmu_linear_psize, mmu_kernel_ssize)); 995 } 996 997 998 DBG(" <- htab_initialize()\n"); 999 } 1000 #undef KB 1001 #undef MB 1002 1003 void __init hash__early_init_devtree(void) 1004 { 1005 /* Initialize segment sizes */ 1006 of_scan_flat_dt(htab_dt_scan_seg_sizes, NULL); 1007 1008 /* Initialize page sizes */ 1009 htab_scan_page_sizes(); 1010 } 1011 1012 static struct hash_mm_context init_hash_mm_context; 1013 void __init hash__early_init_mmu(void) 1014 { 1015 #ifndef CONFIG_PPC_64K_PAGES 1016 /* 1017 * We have code in __hash_page_4K() and elsewhere, which assumes it can 1018 * do the following: 1019 * new_pte |= (slot << H_PAGE_F_GIX_SHIFT) & (H_PAGE_F_SECOND | H_PAGE_F_GIX); 1020 * 1021 * Where the slot number is between 0-15, and values of 8-15 indicate 1022 * the secondary bucket. For that code to work H_PAGE_F_SECOND and 1023 * H_PAGE_F_GIX must occupy four contiguous bits in the PTE, and 1024 * H_PAGE_F_SECOND must be placed above H_PAGE_F_GIX. Assert that here 1025 * with a BUILD_BUG_ON(). 1026 */ 1027 BUILD_BUG_ON(H_PAGE_F_SECOND != (1ul << (H_PAGE_F_GIX_SHIFT + 3))); 1028 #endif /* CONFIG_PPC_64K_PAGES */ 1029 1030 htab_init_page_sizes(); 1031 1032 /* 1033 * initialize page table size 1034 */ 1035 __pte_frag_nr = H_PTE_FRAG_NR; 1036 __pte_frag_size_shift = H_PTE_FRAG_SIZE_SHIFT; 1037 __pmd_frag_nr = H_PMD_FRAG_NR; 1038 __pmd_frag_size_shift = H_PMD_FRAG_SIZE_SHIFT; 1039 1040 __pte_index_size = H_PTE_INDEX_SIZE; 1041 __pmd_index_size = H_PMD_INDEX_SIZE; 1042 __pud_index_size = H_PUD_INDEX_SIZE; 1043 __pgd_index_size = H_PGD_INDEX_SIZE; 1044 __pud_cache_index = H_PUD_CACHE_INDEX; 1045 __pte_table_size = H_PTE_TABLE_SIZE; 1046 __pmd_table_size = H_PMD_TABLE_SIZE; 1047 __pud_table_size = H_PUD_TABLE_SIZE; 1048 __pgd_table_size = H_PGD_TABLE_SIZE; 1049 /* 1050 * 4k use hugepd format, so for hash set then to 1051 * zero 1052 */ 1053 __pmd_val_bits = HASH_PMD_VAL_BITS; 1054 __pud_val_bits = HASH_PUD_VAL_BITS; 1055 __pgd_val_bits = HASH_PGD_VAL_BITS; 1056 1057 __kernel_virt_start = H_KERN_VIRT_START; 1058 __vmalloc_start = H_VMALLOC_START; 1059 __vmalloc_end = H_VMALLOC_END; 1060 __kernel_io_start = H_KERN_IO_START; 1061 __kernel_io_end = H_KERN_IO_END; 1062 vmemmap = (struct page *)H_VMEMMAP_START; 1063 ioremap_bot = IOREMAP_BASE; 1064 1065 #ifdef CONFIG_PCI 1066 pci_io_base = ISA_IO_BASE; 1067 #endif 1068 1069 /* Select appropriate backend */ 1070 if (firmware_has_feature(FW_FEATURE_PS3_LV1)) 1071 ps3_early_mm_init(); 1072 else if (firmware_has_feature(FW_FEATURE_LPAR)) 1073 hpte_init_pseries(); 1074 else if (IS_ENABLED(CONFIG_PPC_NATIVE)) 1075 hpte_init_native(); 1076 1077 if (!mmu_hash_ops.hpte_insert) 1078 panic("hash__early_init_mmu: No MMU hash ops defined!\n"); 1079 1080 /* 1081 * Initialize the MMU Hash table and create the linear mapping 1082 * of memory. Has to be done before SLB initialization as this is 1083 * currently where the page size encoding is obtained. 1084 */ 1085 htab_initialize(); 1086 1087 init_mm.context.hash_context = &init_hash_mm_context; 1088 mm_ctx_set_slb_addr_limit(&init_mm.context, SLB_ADDR_LIMIT_DEFAULT); 1089 1090 pr_info("Initializing hash mmu with SLB\n"); 1091 /* Initialize SLB management */ 1092 slb_initialize(); 1093 1094 if (cpu_has_feature(CPU_FTR_ARCH_206) 1095 && cpu_has_feature(CPU_FTR_HVMODE)) 1096 tlbiel_all(); 1097 } 1098 1099 #ifdef CONFIG_SMP 1100 void hash__early_init_mmu_secondary(void) 1101 { 1102 /* Initialize hash table for that CPU */ 1103 if (!firmware_has_feature(FW_FEATURE_LPAR)) { 1104 1105 if (!cpu_has_feature(CPU_FTR_ARCH_300)) 1106 mtspr(SPRN_SDR1, _SDR1); 1107 else 1108 set_ptcr_when_no_uv(__pa(partition_tb) | 1109 (PATB_SIZE_SHIFT - 12)); 1110 } 1111 /* Initialize SLB */ 1112 slb_initialize(); 1113 1114 if (cpu_has_feature(CPU_FTR_ARCH_206) 1115 && cpu_has_feature(CPU_FTR_HVMODE)) 1116 tlbiel_all(); 1117 1118 #ifdef CONFIG_PPC_MEM_KEYS 1119 if (mmu_has_feature(MMU_FTR_PKEY)) 1120 mtspr(SPRN_UAMOR, default_uamor); 1121 #endif 1122 } 1123 #endif /* CONFIG_SMP */ 1124 1125 /* 1126 * Called by asm hashtable.S for doing lazy icache flush 1127 */ 1128 unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap) 1129 { 1130 struct page *page; 1131 1132 if (!pfn_valid(pte_pfn(pte))) 1133 return pp; 1134 1135 page = pte_page(pte); 1136 1137 /* page is dirty */ 1138 if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) { 1139 if (trap == 0x400) { 1140 flush_dcache_icache_page(page); 1141 set_bit(PG_arch_1, &page->flags); 1142 } else 1143 pp |= HPTE_R_N; 1144 } 1145 return pp; 1146 } 1147 1148 #ifdef CONFIG_PPC_MM_SLICES 1149 static unsigned int get_paca_psize(unsigned long addr) 1150 { 1151 unsigned char *psizes; 1152 unsigned long index, mask_index; 1153 1154 if (addr < SLICE_LOW_TOP) { 1155 psizes = get_paca()->mm_ctx_low_slices_psize; 1156 index = GET_LOW_SLICE_INDEX(addr); 1157 } else { 1158 psizes = get_paca()->mm_ctx_high_slices_psize; 1159 index = GET_HIGH_SLICE_INDEX(addr); 1160 } 1161 mask_index = index & 0x1; 1162 return (psizes[index >> 1] >> (mask_index * 4)) & 0xF; 1163 } 1164 1165 #else 1166 unsigned int get_paca_psize(unsigned long addr) 1167 { 1168 return get_paca()->mm_ctx_user_psize; 1169 } 1170 #endif 1171 1172 /* 1173 * Demote a segment to using 4k pages. 1174 * For now this makes the whole process use 4k pages. 1175 */ 1176 #ifdef CONFIG_PPC_64K_PAGES 1177 void demote_segment_4k(struct mm_struct *mm, unsigned long addr) 1178 { 1179 if (get_slice_psize(mm, addr) == MMU_PAGE_4K) 1180 return; 1181 slice_set_range_psize(mm, addr, 1, MMU_PAGE_4K); 1182 copro_flush_all_slbs(mm); 1183 if ((get_paca_psize(addr) != MMU_PAGE_4K) && (current->mm == mm)) { 1184 1185 copy_mm_to_paca(mm); 1186 slb_flush_and_restore_bolted(); 1187 } 1188 } 1189 #endif /* CONFIG_PPC_64K_PAGES */ 1190 1191 #ifdef CONFIG_PPC_SUBPAGE_PROT 1192 /* 1193 * This looks up a 2-bit protection code for a 4k subpage of a 64k page. 1194 * Userspace sets the subpage permissions using the subpage_prot system call. 1195 * 1196 * Result is 0: full permissions, _PAGE_RW: read-only, 1197 * _PAGE_RWX: no access. 1198 */ 1199 static int subpage_protection(struct mm_struct *mm, unsigned long ea) 1200 { 1201 struct subpage_prot_table *spt = mm_ctx_subpage_prot(&mm->context); 1202 u32 spp = 0; 1203 u32 **sbpm, *sbpp; 1204 1205 if (!spt) 1206 return 0; 1207 1208 if (ea >= spt->maxaddr) 1209 return 0; 1210 if (ea < 0x100000000UL) { 1211 /* addresses below 4GB use spt->low_prot */ 1212 sbpm = spt->low_prot; 1213 } else { 1214 sbpm = spt->protptrs[ea >> SBP_L3_SHIFT]; 1215 if (!sbpm) 1216 return 0; 1217 } 1218 sbpp = sbpm[(ea >> SBP_L2_SHIFT) & (SBP_L2_COUNT - 1)]; 1219 if (!sbpp) 1220 return 0; 1221 spp = sbpp[(ea >> PAGE_SHIFT) & (SBP_L1_COUNT - 1)]; 1222 1223 /* extract 2-bit bitfield for this 4k subpage */ 1224 spp >>= 30 - 2 * ((ea >> 12) & 0xf); 1225 1226 /* 1227 * 0 -> full premission 1228 * 1 -> Read only 1229 * 2 -> no access. 1230 * We return the flag that need to be cleared. 1231 */ 1232 spp = ((spp & 2) ? _PAGE_RWX : 0) | ((spp & 1) ? _PAGE_WRITE : 0); 1233 return spp; 1234 } 1235 1236 #else /* CONFIG_PPC_SUBPAGE_PROT */ 1237 static inline int subpage_protection(struct mm_struct *mm, unsigned long ea) 1238 { 1239 return 0; 1240 } 1241 #endif 1242 1243 void hash_failure_debug(unsigned long ea, unsigned long access, 1244 unsigned long vsid, unsigned long trap, 1245 int ssize, int psize, int lpsize, unsigned long pte) 1246 { 1247 if (!printk_ratelimit()) 1248 return; 1249 pr_info("mm: Hashing failure ! EA=0x%lx access=0x%lx current=%s\n", 1250 ea, access, current->comm); 1251 pr_info(" trap=0x%lx vsid=0x%lx ssize=%d base psize=%d psize %d pte=0x%lx\n", 1252 trap, vsid, ssize, psize, lpsize, pte); 1253 } 1254 1255 static void check_paca_psize(unsigned long ea, struct mm_struct *mm, 1256 int psize, bool user_region) 1257 { 1258 if (user_region) { 1259 if (psize != get_paca_psize(ea)) { 1260 copy_mm_to_paca(mm); 1261 slb_flush_and_restore_bolted(); 1262 } 1263 } else if (get_paca()->vmalloc_sllp != 1264 mmu_psize_defs[mmu_vmalloc_psize].sllp) { 1265 get_paca()->vmalloc_sllp = 1266 mmu_psize_defs[mmu_vmalloc_psize].sllp; 1267 slb_vmalloc_update(); 1268 } 1269 } 1270 1271 /* 1272 * Result code is: 1273 * 0 - handled 1274 * 1 - normal page fault 1275 * -1 - critical hash insertion error 1276 * -2 - access not permitted by subpage protection mechanism 1277 */ 1278 int hash_page_mm(struct mm_struct *mm, unsigned long ea, 1279 unsigned long access, unsigned long trap, 1280 unsigned long flags) 1281 { 1282 bool is_thp; 1283 enum ctx_state prev_state = exception_enter(); 1284 pgd_t *pgdir; 1285 unsigned long vsid; 1286 pte_t *ptep; 1287 unsigned hugeshift; 1288 int rc, user_region = 0; 1289 int psize, ssize; 1290 1291 DBG_LOW("hash_page(ea=%016lx, access=%lx, trap=%lx\n", 1292 ea, access, trap); 1293 trace_hash_fault(ea, access, trap); 1294 1295 /* Get region & vsid */ 1296 switch (get_region_id(ea)) { 1297 case USER_REGION_ID: 1298 user_region = 1; 1299 if (! mm) { 1300 DBG_LOW(" user region with no mm !\n"); 1301 rc = 1; 1302 goto bail; 1303 } 1304 psize = get_slice_psize(mm, ea); 1305 ssize = user_segment_size(ea); 1306 vsid = get_user_vsid(&mm->context, ea, ssize); 1307 break; 1308 case VMALLOC_REGION_ID: 1309 vsid = get_kernel_vsid(ea, mmu_kernel_ssize); 1310 psize = mmu_vmalloc_psize; 1311 ssize = mmu_kernel_ssize; 1312 break; 1313 1314 case IO_REGION_ID: 1315 vsid = get_kernel_vsid(ea, mmu_kernel_ssize); 1316 psize = mmu_io_psize; 1317 ssize = mmu_kernel_ssize; 1318 break; 1319 default: 1320 /* 1321 * Not a valid range 1322 * Send the problem up to do_page_fault() 1323 */ 1324 rc = 1; 1325 goto bail; 1326 } 1327 DBG_LOW(" mm=%p, mm->pgdir=%p, vsid=%016lx\n", mm, mm->pgd, vsid); 1328 1329 /* Bad address. */ 1330 if (!vsid) { 1331 DBG_LOW("Bad address!\n"); 1332 rc = 1; 1333 goto bail; 1334 } 1335 /* Get pgdir */ 1336 pgdir = mm->pgd; 1337 if (pgdir == NULL) { 1338 rc = 1; 1339 goto bail; 1340 } 1341 1342 /* Check CPU locality */ 1343 if (user_region && mm_is_thread_local(mm)) 1344 flags |= HPTE_LOCAL_UPDATE; 1345 1346 #ifndef CONFIG_PPC_64K_PAGES 1347 /* 1348 * If we use 4K pages and our psize is not 4K, then we might 1349 * be hitting a special driver mapping, and need to align the 1350 * address before we fetch the PTE. 1351 * 1352 * It could also be a hugepage mapping, in which case this is 1353 * not necessary, but it's not harmful, either. 1354 */ 1355 if (psize != MMU_PAGE_4K) 1356 ea &= ~((1ul << mmu_psize_defs[psize].shift) - 1); 1357 #endif /* CONFIG_PPC_64K_PAGES */ 1358 1359 /* Get PTE and page size from page tables */ 1360 ptep = find_linux_pte(pgdir, ea, &is_thp, &hugeshift); 1361 if (ptep == NULL || !pte_present(*ptep)) { 1362 DBG_LOW(" no PTE !\n"); 1363 rc = 1; 1364 goto bail; 1365 } 1366 1367 /* 1368 * Add _PAGE_PRESENT to the required access perm. If there are parallel 1369 * updates to the pte that can possibly clear _PAGE_PTE, catch that too. 1370 * 1371 * We can safely use the return pte address in rest of the function 1372 * because we do set H_PAGE_BUSY which prevents further updates to pte 1373 * from generic code. 1374 */ 1375 access |= _PAGE_PRESENT | _PAGE_PTE; 1376 1377 /* 1378 * Pre-check access permissions (will be re-checked atomically 1379 * in __hash_page_XX but this pre-check is a fast path 1380 */ 1381 if (!check_pte_access(access, pte_val(*ptep))) { 1382 DBG_LOW(" no access !\n"); 1383 rc = 1; 1384 goto bail; 1385 } 1386 1387 if (hugeshift) { 1388 if (is_thp) 1389 rc = __hash_page_thp(ea, access, vsid, (pmd_t *)ptep, 1390 trap, flags, ssize, psize); 1391 #ifdef CONFIG_HUGETLB_PAGE 1392 else 1393 rc = __hash_page_huge(ea, access, vsid, ptep, trap, 1394 flags, ssize, hugeshift, psize); 1395 #else 1396 else { 1397 /* 1398 * if we have hugeshift, and is not transhuge with 1399 * hugetlb disabled, something is really wrong. 1400 */ 1401 rc = 1; 1402 WARN_ON(1); 1403 } 1404 #endif 1405 if (current->mm == mm) 1406 check_paca_psize(ea, mm, psize, user_region); 1407 1408 goto bail; 1409 } 1410 1411 #ifndef CONFIG_PPC_64K_PAGES 1412 DBG_LOW(" i-pte: %016lx\n", pte_val(*ptep)); 1413 #else 1414 DBG_LOW(" i-pte: %016lx %016lx\n", pte_val(*ptep), 1415 pte_val(*(ptep + PTRS_PER_PTE))); 1416 #endif 1417 /* Do actual hashing */ 1418 #ifdef CONFIG_PPC_64K_PAGES 1419 /* If H_PAGE_4K_PFN is set, make sure this is a 4k segment */ 1420 if ((pte_val(*ptep) & H_PAGE_4K_PFN) && psize == MMU_PAGE_64K) { 1421 demote_segment_4k(mm, ea); 1422 psize = MMU_PAGE_4K; 1423 } 1424 1425 /* 1426 * If this PTE is non-cacheable and we have restrictions on 1427 * using non cacheable large pages, then we switch to 4k 1428 */ 1429 if (mmu_ci_restrictions && psize == MMU_PAGE_64K && pte_ci(*ptep)) { 1430 if (user_region) { 1431 demote_segment_4k(mm, ea); 1432 psize = MMU_PAGE_4K; 1433 } else if (ea < VMALLOC_END) { 1434 /* 1435 * some driver did a non-cacheable mapping 1436 * in vmalloc space, so switch vmalloc 1437 * to 4k pages 1438 */ 1439 printk(KERN_ALERT "Reducing vmalloc segment " 1440 "to 4kB pages because of " 1441 "non-cacheable mapping\n"); 1442 psize = mmu_vmalloc_psize = MMU_PAGE_4K; 1443 copro_flush_all_slbs(mm); 1444 } 1445 } 1446 1447 #endif /* CONFIG_PPC_64K_PAGES */ 1448 1449 if (current->mm == mm) 1450 check_paca_psize(ea, mm, psize, user_region); 1451 1452 #ifdef CONFIG_PPC_64K_PAGES 1453 if (psize == MMU_PAGE_64K) 1454 rc = __hash_page_64K(ea, access, vsid, ptep, trap, 1455 flags, ssize); 1456 else 1457 #endif /* CONFIG_PPC_64K_PAGES */ 1458 { 1459 int spp = subpage_protection(mm, ea); 1460 if (access & spp) 1461 rc = -2; 1462 else 1463 rc = __hash_page_4K(ea, access, vsid, ptep, trap, 1464 flags, ssize, spp); 1465 } 1466 1467 /* 1468 * Dump some info in case of hash insertion failure, they should 1469 * never happen so it is really useful to know if/when they do 1470 */ 1471 if (rc == -1) 1472 hash_failure_debug(ea, access, vsid, trap, ssize, psize, 1473 psize, pte_val(*ptep)); 1474 #ifndef CONFIG_PPC_64K_PAGES 1475 DBG_LOW(" o-pte: %016lx\n", pte_val(*ptep)); 1476 #else 1477 DBG_LOW(" o-pte: %016lx %016lx\n", pte_val(*ptep), 1478 pte_val(*(ptep + PTRS_PER_PTE))); 1479 #endif 1480 DBG_LOW(" -> rc=%d\n", rc); 1481 1482 bail: 1483 exception_exit(prev_state); 1484 return rc; 1485 } 1486 EXPORT_SYMBOL_GPL(hash_page_mm); 1487 1488 int hash_page(unsigned long ea, unsigned long access, unsigned long trap, 1489 unsigned long dsisr) 1490 { 1491 unsigned long flags = 0; 1492 struct mm_struct *mm = current->mm; 1493 1494 if ((get_region_id(ea) == VMALLOC_REGION_ID) || 1495 (get_region_id(ea) == IO_REGION_ID)) 1496 mm = &init_mm; 1497 1498 if (dsisr & DSISR_NOHPTE) 1499 flags |= HPTE_NOHPTE_UPDATE; 1500 1501 return hash_page_mm(mm, ea, access, trap, flags); 1502 } 1503 EXPORT_SYMBOL_GPL(hash_page); 1504 1505 int __hash_page(unsigned long trap, unsigned long ea, unsigned long dsisr, 1506 unsigned long msr) 1507 { 1508 unsigned long access = _PAGE_PRESENT | _PAGE_READ; 1509 unsigned long flags = 0; 1510 struct mm_struct *mm = current->mm; 1511 unsigned int region_id = get_region_id(ea); 1512 1513 if ((region_id == VMALLOC_REGION_ID) || (region_id == IO_REGION_ID)) 1514 mm = &init_mm; 1515 1516 if (dsisr & DSISR_NOHPTE) 1517 flags |= HPTE_NOHPTE_UPDATE; 1518 1519 if (dsisr & DSISR_ISSTORE) 1520 access |= _PAGE_WRITE; 1521 /* 1522 * We set _PAGE_PRIVILEGED only when 1523 * kernel mode access kernel space. 1524 * 1525 * _PAGE_PRIVILEGED is NOT set 1526 * 1) when kernel mode access user space 1527 * 2) user space access kernel space. 1528 */ 1529 access |= _PAGE_PRIVILEGED; 1530 if ((msr & MSR_PR) || (region_id == USER_REGION_ID)) 1531 access &= ~_PAGE_PRIVILEGED; 1532 1533 if (trap == 0x400) 1534 access |= _PAGE_EXEC; 1535 1536 return hash_page_mm(mm, ea, access, trap, flags); 1537 } 1538 1539 #ifdef CONFIG_PPC_MM_SLICES 1540 static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) 1541 { 1542 int psize = get_slice_psize(mm, ea); 1543 1544 /* We only prefault standard pages for now */ 1545 if (unlikely(psize != mm_ctx_user_psize(&mm->context))) 1546 return false; 1547 1548 /* 1549 * Don't prefault if subpage protection is enabled for the EA. 1550 */ 1551 if (unlikely((psize == MMU_PAGE_4K) && subpage_protection(mm, ea))) 1552 return false; 1553 1554 return true; 1555 } 1556 #else 1557 static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) 1558 { 1559 return true; 1560 } 1561 #endif 1562 1563 static void hash_preload(struct mm_struct *mm, pte_t *ptep, unsigned long ea, 1564 bool is_exec, unsigned long trap) 1565 { 1566 unsigned long vsid; 1567 pgd_t *pgdir; 1568 int rc, ssize, update_flags = 0; 1569 unsigned long access = _PAGE_PRESENT | _PAGE_READ | (is_exec ? _PAGE_EXEC : 0); 1570 unsigned long flags; 1571 1572 BUG_ON(get_region_id(ea) != USER_REGION_ID); 1573 1574 if (!should_hash_preload(mm, ea)) 1575 return; 1576 1577 DBG_LOW("hash_preload(mm=%p, mm->pgdir=%p, ea=%016lx, access=%lx," 1578 " trap=%lx\n", mm, mm->pgd, ea, access, trap); 1579 1580 /* Get Linux PTE if available */ 1581 pgdir = mm->pgd; 1582 if (pgdir == NULL) 1583 return; 1584 1585 /* Get VSID */ 1586 ssize = user_segment_size(ea); 1587 vsid = get_user_vsid(&mm->context, ea, ssize); 1588 if (!vsid) 1589 return; 1590 1591 #ifdef CONFIG_PPC_64K_PAGES 1592 /* If either H_PAGE_4K_PFN or cache inhibited is set (and we are on 1593 * a 64K kernel), then we don't preload, hash_page() will take 1594 * care of it once we actually try to access the page. 1595 * That way we don't have to duplicate all of the logic for segment 1596 * page size demotion here 1597 * Called with PTL held, hence can be sure the value won't change in 1598 * between. 1599 */ 1600 if ((pte_val(*ptep) & H_PAGE_4K_PFN) || pte_ci(*ptep)) 1601 return; 1602 #endif /* CONFIG_PPC_64K_PAGES */ 1603 1604 /* 1605 * __hash_page_* must run with interrupts off, as it sets the 1606 * H_PAGE_BUSY bit. It's possible for perf interrupts to hit at any 1607 * time and may take a hash fault reading the user stack, see 1608 * read_user_stack_slow() in the powerpc/perf code. 1609 * 1610 * If that takes a hash fault on the same page as we lock here, it 1611 * will bail out when seeing H_PAGE_BUSY set, and retry the access 1612 * leading to an infinite loop. 1613 * 1614 * Disabling interrupts here does not prevent perf interrupts, but it 1615 * will prevent them taking hash faults (see the NMI test in 1616 * do_hash_page), then read_user_stack's copy_from_user_nofault will 1617 * fail and perf will fall back to read_user_stack_slow(), which 1618 * walks the Linux page tables. 1619 * 1620 * Interrupts must also be off for the duration of the 1621 * mm_is_thread_local test and update, to prevent preempt running the 1622 * mm on another CPU (XXX: this may be racy vs kthread_use_mm). 1623 */ 1624 local_irq_save(flags); 1625 1626 /* Is that local to this CPU ? */ 1627 if (mm_is_thread_local(mm)) 1628 update_flags |= HPTE_LOCAL_UPDATE; 1629 1630 /* Hash it in */ 1631 #ifdef CONFIG_PPC_64K_PAGES 1632 if (mm_ctx_user_psize(&mm->context) == MMU_PAGE_64K) 1633 rc = __hash_page_64K(ea, access, vsid, ptep, trap, 1634 update_flags, ssize); 1635 else 1636 #endif /* CONFIG_PPC_64K_PAGES */ 1637 rc = __hash_page_4K(ea, access, vsid, ptep, trap, update_flags, 1638 ssize, subpage_protection(mm, ea)); 1639 1640 /* Dump some info in case of hash insertion failure, they should 1641 * never happen so it is really useful to know if/when they do 1642 */ 1643 if (rc == -1) 1644 hash_failure_debug(ea, access, vsid, trap, ssize, 1645 mm_ctx_user_psize(&mm->context), 1646 mm_ctx_user_psize(&mm->context), 1647 pte_val(*ptep)); 1648 1649 local_irq_restore(flags); 1650 } 1651 1652 /* 1653 * This is called at the end of handling a user page fault, when the 1654 * fault has been handled by updating a PTE in the linux page tables. 1655 * We use it to preload an HPTE into the hash table corresponding to 1656 * the updated linux PTE. 1657 * 1658 * This must always be called with the pte lock held. 1659 */ 1660 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 1661 pte_t *ptep) 1662 { 1663 /* 1664 * We don't need to worry about _PAGE_PRESENT here because we are 1665 * called with either mm->page_table_lock held or ptl lock held 1666 */ 1667 unsigned long trap; 1668 bool is_exec; 1669 1670 if (radix_enabled()) 1671 return; 1672 1673 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 1674 if (!pte_young(*ptep) || address >= TASK_SIZE) 1675 return; 1676 1677 /* 1678 * We try to figure out if we are coming from an instruction 1679 * access fault and pass that down to __hash_page so we avoid 1680 * double-faulting on execution of fresh text. We have to test 1681 * for regs NULL since init will get here first thing at boot. 1682 * 1683 * We also avoid filling the hash if not coming from a fault. 1684 */ 1685 1686 trap = current->thread.regs ? TRAP(current->thread.regs) : 0UL; 1687 switch (trap) { 1688 case 0x300: 1689 is_exec = false; 1690 break; 1691 case 0x400: 1692 is_exec = true; 1693 break; 1694 default: 1695 return; 1696 } 1697 1698 hash_preload(vma->vm_mm, ptep, address, is_exec, trap); 1699 } 1700 1701 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1702 static inline void tm_flush_hash_page(int local) 1703 { 1704 /* 1705 * Transactions are not aborted by tlbiel, only tlbie. Without, syncing a 1706 * page back to a block device w/PIO could pick up transactional data 1707 * (bad!) so we force an abort here. Before the sync the page will be 1708 * made read-only, which will flush_hash_page. BIG ISSUE here: if the 1709 * kernel uses a page from userspace without unmapping it first, it may 1710 * see the speculated version. 1711 */ 1712 if (local && cpu_has_feature(CPU_FTR_TM) && current->thread.regs && 1713 MSR_TM_ACTIVE(current->thread.regs->msr)) { 1714 tm_enable(); 1715 tm_abort(TM_CAUSE_TLBI); 1716 } 1717 } 1718 #else 1719 static inline void tm_flush_hash_page(int local) 1720 { 1721 } 1722 #endif 1723 1724 /* 1725 * Return the global hash slot, corresponding to the given PTE, which contains 1726 * the HPTE. 1727 */ 1728 unsigned long pte_get_hash_gslot(unsigned long vpn, unsigned long shift, 1729 int ssize, real_pte_t rpte, unsigned int subpg_index) 1730 { 1731 unsigned long hash, gslot, hidx; 1732 1733 hash = hpt_hash(vpn, shift, ssize); 1734 hidx = __rpte_to_hidx(rpte, subpg_index); 1735 if (hidx & _PTEIDX_SECONDARY) 1736 hash = ~hash; 1737 gslot = (hash & htab_hash_mask) * HPTES_PER_GROUP; 1738 gslot += hidx & _PTEIDX_GROUP_IX; 1739 return gslot; 1740 } 1741 1742 void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize, 1743 unsigned long flags) 1744 { 1745 unsigned long index, shift, gslot; 1746 int local = flags & HPTE_LOCAL_UPDATE; 1747 1748 DBG_LOW("flush_hash_page(vpn=%016lx)\n", vpn); 1749 pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) { 1750 gslot = pte_get_hash_gslot(vpn, shift, ssize, pte, index); 1751 DBG_LOW(" sub %ld: gslot=%lx\n", index, gslot); 1752 /* 1753 * We use same base page size and actual psize, because we don't 1754 * use these functions for hugepage 1755 */ 1756 mmu_hash_ops.hpte_invalidate(gslot, vpn, psize, psize, 1757 ssize, local); 1758 } pte_iterate_hashed_end(); 1759 1760 tm_flush_hash_page(local); 1761 } 1762 1763 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1764 void flush_hash_hugepage(unsigned long vsid, unsigned long addr, 1765 pmd_t *pmdp, unsigned int psize, int ssize, 1766 unsigned long flags) 1767 { 1768 int i, max_hpte_count, valid; 1769 unsigned long s_addr; 1770 unsigned char *hpte_slot_array; 1771 unsigned long hidx, shift, vpn, hash, slot; 1772 int local = flags & HPTE_LOCAL_UPDATE; 1773 1774 s_addr = addr & HPAGE_PMD_MASK; 1775 hpte_slot_array = get_hpte_slot_array(pmdp); 1776 /* 1777 * IF we try to do a HUGE PTE update after a withdraw is done. 1778 * we will find the below NULL. This happens when we do 1779 * split_huge_pmd 1780 */ 1781 if (!hpte_slot_array) 1782 return; 1783 1784 if (mmu_hash_ops.hugepage_invalidate) { 1785 mmu_hash_ops.hugepage_invalidate(vsid, s_addr, hpte_slot_array, 1786 psize, ssize, local); 1787 goto tm_abort; 1788 } 1789 /* 1790 * No bluk hpte removal support, invalidate each entry 1791 */ 1792 shift = mmu_psize_defs[psize].shift; 1793 max_hpte_count = HPAGE_PMD_SIZE >> shift; 1794 for (i = 0; i < max_hpte_count; i++) { 1795 /* 1796 * 8 bits per each hpte entries 1797 * 000| [ secondary group (one bit) | hidx (3 bits) | valid bit] 1798 */ 1799 valid = hpte_valid(hpte_slot_array, i); 1800 if (!valid) 1801 continue; 1802 hidx = hpte_hash_index(hpte_slot_array, i); 1803 1804 /* get the vpn */ 1805 addr = s_addr + (i * (1ul << shift)); 1806 vpn = hpt_vpn(addr, vsid, ssize); 1807 hash = hpt_hash(vpn, shift, ssize); 1808 if (hidx & _PTEIDX_SECONDARY) 1809 hash = ~hash; 1810 1811 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; 1812 slot += hidx & _PTEIDX_GROUP_IX; 1813 mmu_hash_ops.hpte_invalidate(slot, vpn, psize, 1814 MMU_PAGE_16M, ssize, local); 1815 } 1816 tm_abort: 1817 tm_flush_hash_page(local); 1818 } 1819 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1820 1821 void flush_hash_range(unsigned long number, int local) 1822 { 1823 if (mmu_hash_ops.flush_hash_range) 1824 mmu_hash_ops.flush_hash_range(number, local); 1825 else { 1826 int i; 1827 struct ppc64_tlb_batch *batch = 1828 this_cpu_ptr(&ppc64_tlb_batch); 1829 1830 for (i = 0; i < number; i++) 1831 flush_hash_page(batch->vpn[i], batch->pte[i], 1832 batch->psize, batch->ssize, local); 1833 } 1834 } 1835 1836 /* 1837 * low_hash_fault is called when we the low level hash code failed 1838 * to instert a PTE due to an hypervisor error 1839 */ 1840 void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc) 1841 { 1842 enum ctx_state prev_state = exception_enter(); 1843 1844 if (user_mode(regs)) { 1845 #ifdef CONFIG_PPC_SUBPAGE_PROT 1846 if (rc == -2) 1847 _exception(SIGSEGV, regs, SEGV_ACCERR, address); 1848 else 1849 #endif 1850 _exception(SIGBUS, regs, BUS_ADRERR, address); 1851 } else 1852 bad_page_fault(regs, address, SIGBUS); 1853 1854 exception_exit(prev_state); 1855 } 1856 1857 long hpte_insert_repeating(unsigned long hash, unsigned long vpn, 1858 unsigned long pa, unsigned long rflags, 1859 unsigned long vflags, int psize, int ssize) 1860 { 1861 unsigned long hpte_group; 1862 long slot; 1863 1864 repeat: 1865 hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP; 1866 1867 /* Insert into the hash table, primary slot */ 1868 slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, vflags, 1869 psize, psize, ssize); 1870 1871 /* Primary is full, try the secondary */ 1872 if (unlikely(slot == -1)) { 1873 hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP; 1874 slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, 1875 vflags | HPTE_V_SECONDARY, 1876 psize, psize, ssize); 1877 if (slot == -1) { 1878 if (mftb() & 0x1) 1879 hpte_group = (hash & htab_hash_mask) * 1880 HPTES_PER_GROUP; 1881 1882 mmu_hash_ops.hpte_remove(hpte_group); 1883 goto repeat; 1884 } 1885 } 1886 1887 return slot; 1888 } 1889 1890 #ifdef CONFIG_DEBUG_PAGEALLOC 1891 static void kernel_map_linear_page(unsigned long vaddr, unsigned long lmi) 1892 { 1893 unsigned long hash; 1894 unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize); 1895 unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize); 1896 unsigned long mode = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL)); 1897 long ret; 1898 1899 hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize); 1900 1901 /* Don't create HPTE entries for bad address */ 1902 if (!vsid) 1903 return; 1904 1905 ret = hpte_insert_repeating(hash, vpn, __pa(vaddr), mode, 1906 HPTE_V_BOLTED, 1907 mmu_linear_psize, mmu_kernel_ssize); 1908 1909 BUG_ON (ret < 0); 1910 spin_lock(&linear_map_hash_lock); 1911 BUG_ON(linear_map_hash_slots[lmi] & 0x80); 1912 linear_map_hash_slots[lmi] = ret | 0x80; 1913 spin_unlock(&linear_map_hash_lock); 1914 } 1915 1916 static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi) 1917 { 1918 unsigned long hash, hidx, slot; 1919 unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize); 1920 unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize); 1921 1922 hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize); 1923 spin_lock(&linear_map_hash_lock); 1924 BUG_ON(!(linear_map_hash_slots[lmi] & 0x80)); 1925 hidx = linear_map_hash_slots[lmi] & 0x7f; 1926 linear_map_hash_slots[lmi] = 0; 1927 spin_unlock(&linear_map_hash_lock); 1928 if (hidx & _PTEIDX_SECONDARY) 1929 hash = ~hash; 1930 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; 1931 slot += hidx & _PTEIDX_GROUP_IX; 1932 mmu_hash_ops.hpte_invalidate(slot, vpn, mmu_linear_psize, 1933 mmu_linear_psize, 1934 mmu_kernel_ssize, 0); 1935 } 1936 1937 void __kernel_map_pages(struct page *page, int numpages, int enable) 1938 { 1939 unsigned long flags, vaddr, lmi; 1940 int i; 1941 1942 local_irq_save(flags); 1943 for (i = 0; i < numpages; i++, page++) { 1944 vaddr = (unsigned long)page_address(page); 1945 lmi = __pa(vaddr) >> PAGE_SHIFT; 1946 if (lmi >= linear_map_hash_count) 1947 continue; 1948 if (enable) 1949 kernel_map_linear_page(vaddr, lmi); 1950 else 1951 kernel_unmap_linear_page(vaddr, lmi); 1952 } 1953 local_irq_restore(flags); 1954 } 1955 #endif /* CONFIG_DEBUG_PAGEALLOC */ 1956 1957 void hash__setup_initial_memory_limit(phys_addr_t first_memblock_base, 1958 phys_addr_t first_memblock_size) 1959 { 1960 /* 1961 * We don't currently support the first MEMBLOCK not mapping 0 1962 * physical on those processors 1963 */ 1964 BUG_ON(first_memblock_base != 0); 1965 1966 /* 1967 * On virtualized systems the first entry is our RMA region aka VRMA, 1968 * non-virtualized 64-bit hash MMU systems don't have a limitation 1969 * on real mode access. 1970 * 1971 * For guests on platforms before POWER9, we clamp the it limit to 1G 1972 * to avoid some funky things such as RTAS bugs etc... 1973 * 1974 * On POWER9 we limit to 1TB in case the host erroneously told us that 1975 * the RMA was >1TB. Effective address bits 0:23 are treated as zero 1976 * (meaning the access is aliased to zero i.e. addr = addr % 1TB) 1977 * for virtual real mode addressing and so it doesn't make sense to 1978 * have an area larger than 1TB as it can't be addressed. 1979 */ 1980 if (!early_cpu_has_feature(CPU_FTR_HVMODE)) { 1981 ppc64_rma_size = first_memblock_size; 1982 if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) 1983 ppc64_rma_size = min_t(u64, ppc64_rma_size, 0x40000000); 1984 else 1985 ppc64_rma_size = min_t(u64, ppc64_rma_size, 1986 1UL << SID_SHIFT_1T); 1987 1988 /* Finally limit subsequent allocations */ 1989 memblock_set_current_limit(ppc64_rma_size); 1990 } else { 1991 ppc64_rma_size = ULONG_MAX; 1992 } 1993 } 1994 1995 #ifdef CONFIG_DEBUG_FS 1996 1997 static int hpt_order_get(void *data, u64 *val) 1998 { 1999 *val = ppc64_pft_size; 2000 return 0; 2001 } 2002 2003 static int hpt_order_set(void *data, u64 val) 2004 { 2005 int ret; 2006 2007 if (!mmu_hash_ops.resize_hpt) 2008 return -ENODEV; 2009 2010 cpus_read_lock(); 2011 ret = mmu_hash_ops.resize_hpt(val); 2012 cpus_read_unlock(); 2013 2014 return ret; 2015 } 2016 2017 DEFINE_DEBUGFS_ATTRIBUTE(fops_hpt_order, hpt_order_get, hpt_order_set, "%llu\n"); 2018 2019 static int __init hash64_debugfs(void) 2020 { 2021 debugfs_create_file("hpt_order", 0600, powerpc_debugfs_root, NULL, 2022 &fops_hpt_order); 2023 return 0; 2024 } 2025 machine_device_initcall(pseries, hash64_debugfs); 2026 #endif /* CONFIG_DEBUG_FS */ 2027 2028 void __init print_system_hash_info(void) 2029 { 2030 pr_info("ppc64_pft_size = 0x%llx\n", ppc64_pft_size); 2031 2032 if (htab_hash_mask) 2033 pr_info("htab_hash_mask = 0x%lx\n", htab_hash_mask); 2034 } 2035