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 #include <linux/debugfs.h> 40 41 #include <asm/interrupt.h> 42 #include <asm/processor.h> 43 #include <asm/mmu.h> 44 #include <asm/mmu_context.h> 45 #include <asm/page.h> 46 #include <asm/types.h> 47 #include <linux/uaccess.h> 48 #include <asm/machdep.h> 49 #include <asm/prom.h> 50 #include <asm/io.h> 51 #include <asm/eeh.h> 52 #include <asm/tlb.h> 53 #include <asm/cacheflush.h> 54 #include <asm/cputable.h> 55 #include <asm/sections.h> 56 #include <asm/copro.h> 57 #include <asm/udbg.h> 58 #include <asm/code-patching.h> 59 #include <asm/fadump.h> 60 #include <asm/firmware.h> 61 #include <asm/tm.h> 62 #include <asm/trace.h> 63 #include <asm/ps3.h> 64 #include <asm/pte-walk.h> 65 #include <asm/asm-prototypes.h> 66 #include <asm/ultravisor.h> 67 68 #include <mm/mmu_decl.h> 69 70 #include "internal.h" 71 72 73 #ifdef DEBUG 74 #define DBG(fmt...) udbg_printf(fmt) 75 #else 76 #define DBG(fmt...) 77 #endif 78 79 #ifdef DEBUG_LOW 80 #define DBG_LOW(fmt...) udbg_printf(fmt) 81 #else 82 #define DBG_LOW(fmt...) 83 #endif 84 85 #define KB (1024) 86 #define MB (1024*KB) 87 #define GB (1024L*MB) 88 89 /* 90 * Note: pte --> Linux PTE 91 * HPTE --> PowerPC Hashed Page Table Entry 92 * 93 * Execution context: 94 * htab_initialize is called with the MMU off (of course), but 95 * the kernel has been copied down to zero so it can directly 96 * reference global data. At this point it is very difficult 97 * to print debug info. 98 * 99 */ 100 101 static unsigned long _SDR1; 102 103 u8 hpte_page_sizes[1 << LP_BITS]; 104 EXPORT_SYMBOL_GPL(hpte_page_sizes); 105 106 struct hash_pte *htab_address; 107 unsigned long htab_size_bytes; 108 unsigned long htab_hash_mask; 109 EXPORT_SYMBOL_GPL(htab_hash_mask); 110 int mmu_linear_psize = MMU_PAGE_4K; 111 EXPORT_SYMBOL_GPL(mmu_linear_psize); 112 int mmu_virtual_psize = MMU_PAGE_4K; 113 int mmu_vmalloc_psize = MMU_PAGE_4K; 114 EXPORT_SYMBOL_GPL(mmu_vmalloc_psize); 115 int mmu_io_psize = MMU_PAGE_4K; 116 int mmu_kernel_ssize = MMU_SEGSIZE_256M; 117 EXPORT_SYMBOL_GPL(mmu_kernel_ssize); 118 int mmu_highuser_ssize = MMU_SEGSIZE_256M; 119 u16 mmu_slb_size = 64; 120 EXPORT_SYMBOL_GPL(mmu_slb_size); 121 #ifdef CONFIG_PPC_64K_PAGES 122 int mmu_ci_restrictions; 123 #endif 124 #ifdef CONFIG_DEBUG_PAGEALLOC 125 static u8 *linear_map_hash_slots; 126 static unsigned long linear_map_hash_count; 127 static DEFINE_SPINLOCK(linear_map_hash_lock); 128 #endif /* CONFIG_DEBUG_PAGEALLOC */ 129 struct mmu_hash_ops mmu_hash_ops; 130 EXPORT_SYMBOL(mmu_hash_ops); 131 132 /* 133 * These are definitions of page sizes arrays to be used when none 134 * is provided by the firmware. 135 */ 136 137 /* 138 * Fallback (4k pages only) 139 */ 140 static struct mmu_psize_def mmu_psize_defaults[] = { 141 [MMU_PAGE_4K] = { 142 .shift = 12, 143 .sllp = 0, 144 .penc = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1}, 145 .avpnm = 0, 146 .tlbiel = 0, 147 }, 148 }; 149 150 /* 151 * POWER4, GPUL, POWER5 152 * 153 * Support for 16Mb large pages 154 */ 155 static struct mmu_psize_def mmu_psize_defaults_gp[] = { 156 [MMU_PAGE_4K] = { 157 .shift = 12, 158 .sllp = 0, 159 .penc = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1}, 160 .avpnm = 0, 161 .tlbiel = 1, 162 }, 163 [MMU_PAGE_16M] = { 164 .shift = 24, 165 .sllp = SLB_VSID_L, 166 .penc = {[0 ... MMU_PAGE_16M - 1] = -1, [MMU_PAGE_16M] = 0, 167 [MMU_PAGE_16M + 1 ... MMU_PAGE_COUNT - 1] = -1 }, 168 .avpnm = 0x1UL, 169 .tlbiel = 0, 170 }, 171 }; 172 173 static inline void tlbiel_hash_set_isa206(unsigned int set, unsigned int is) 174 { 175 unsigned long rb; 176 177 rb = (set << PPC_BITLSHIFT(51)) | (is << PPC_BITLSHIFT(53)); 178 179 asm volatile("tlbiel %0" : : "r" (rb)); 180 } 181 182 /* 183 * tlbiel instruction for hash, set invalidation 184 * i.e., r=1 and is=01 or is=10 or is=11 185 */ 186 static __always_inline void tlbiel_hash_set_isa300(unsigned int set, unsigned int is, 187 unsigned int pid, 188 unsigned int ric, unsigned int prs) 189 { 190 unsigned long rb; 191 unsigned long rs; 192 unsigned int r = 0; /* hash format */ 193 194 rb = (set << PPC_BITLSHIFT(51)) | (is << PPC_BITLSHIFT(53)); 195 rs = ((unsigned long)pid << PPC_BITLSHIFT(31)); 196 197 asm volatile(PPC_TLBIEL(%0, %1, %2, %3, %4) 198 : : "r"(rb), "r"(rs), "i"(ric), "i"(prs), "i"(r) 199 : "memory"); 200 } 201 202 203 static void tlbiel_all_isa206(unsigned int num_sets, unsigned int is) 204 { 205 unsigned int set; 206 207 asm volatile("ptesync": : :"memory"); 208 209 for (set = 0; set < num_sets; set++) 210 tlbiel_hash_set_isa206(set, is); 211 212 ppc_after_tlbiel_barrier(); 213 } 214 215 static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is) 216 { 217 unsigned int set; 218 219 asm volatile("ptesync": : :"memory"); 220 221 /* 222 * Flush the partition table cache if this is HV mode. 223 */ 224 if (early_cpu_has_feature(CPU_FTR_HVMODE)) 225 tlbiel_hash_set_isa300(0, is, 0, 2, 0); 226 227 /* 228 * Now invalidate the process table cache. UPRT=0 HPT modes (what 229 * current hardware implements) do not use the process table, but 230 * add the flushes anyway. 231 * 232 * From ISA v3.0B p. 1078: 233 * The following forms are invalid. 234 * * PRS=1, R=0, and RIC!=2 (The only process-scoped 235 * HPT caching is of the Process Table.) 236 */ 237 tlbiel_hash_set_isa300(0, is, 0, 2, 1); 238 239 /* 240 * Then flush the sets of the TLB proper. Hash mode uses 241 * partition scoped TLB translations, which may be flushed 242 * in !HV mode. 243 */ 244 for (set = 0; set < num_sets; set++) 245 tlbiel_hash_set_isa300(set, is, 0, 0, 0); 246 247 ppc_after_tlbiel_barrier(); 248 249 asm volatile(PPC_ISA_3_0_INVALIDATE_ERAT "; isync" : : :"memory"); 250 } 251 252 void hash__tlbiel_all(unsigned int action) 253 { 254 unsigned int is; 255 256 switch (action) { 257 case TLB_INVAL_SCOPE_GLOBAL: 258 is = 3; 259 break; 260 case TLB_INVAL_SCOPE_LPID: 261 is = 2; 262 break; 263 default: 264 BUG(); 265 } 266 267 if (early_cpu_has_feature(CPU_FTR_ARCH_300)) 268 tlbiel_all_isa300(POWER9_TLB_SETS_HASH, is); 269 else if (early_cpu_has_feature(CPU_FTR_ARCH_207S)) 270 tlbiel_all_isa206(POWER8_TLB_SETS, is); 271 else if (early_cpu_has_feature(CPU_FTR_ARCH_206)) 272 tlbiel_all_isa206(POWER7_TLB_SETS, is); 273 else 274 WARN(1, "%s called on pre-POWER7 CPU\n", __func__); 275 } 276 277 /* 278 * 'R' and 'C' update notes: 279 * - Under pHyp or KVM, the updatepp path will not set C, thus it *will* 280 * create writeable HPTEs without C set, because the hcall H_PROTECT 281 * that we use in that case will not update C 282 * - The above is however not a problem, because we also don't do that 283 * fancy "no flush" variant of eviction and we use H_REMOVE which will 284 * do the right thing and thus we don't have the race I described earlier 285 * 286 * - Under bare metal, we do have the race, so we need R and C set 287 * - We make sure R is always set and never lost 288 * - C is _PAGE_DIRTY, and *should* always be set for a writeable mapping 289 */ 290 unsigned long htab_convert_pte_flags(unsigned long pteflags, unsigned long flags) 291 { 292 unsigned long rflags = 0; 293 294 /* _PAGE_EXEC -> NOEXEC */ 295 if ((pteflags & _PAGE_EXEC) == 0) 296 rflags |= HPTE_R_N; 297 /* 298 * PPP bits: 299 * Linux uses slb key 0 for kernel and 1 for user. 300 * kernel RW areas are mapped with PPP=0b000 301 * User area is mapped with PPP=0b010 for read/write 302 * or PPP=0b011 for read-only (including writeable but clean pages). 303 */ 304 if (pteflags & _PAGE_PRIVILEGED) { 305 /* 306 * Kernel read only mapped with ppp bits 0b110 307 */ 308 if (!(pteflags & _PAGE_WRITE)) { 309 if (mmu_has_feature(MMU_FTR_KERNEL_RO)) 310 rflags |= (HPTE_R_PP0 | 0x2); 311 else 312 rflags |= 0x3; 313 } 314 } else { 315 if (pteflags & _PAGE_RWX) 316 rflags |= 0x2; 317 if (!((pteflags & _PAGE_WRITE) && (pteflags & _PAGE_DIRTY))) 318 rflags |= 0x1; 319 } 320 /* 321 * We can't allow hardware to update hpte bits. Hence always 322 * set 'R' bit and set 'C' if it is a write fault 323 */ 324 rflags |= HPTE_R_R; 325 326 if (pteflags & _PAGE_DIRTY) 327 rflags |= HPTE_R_C; 328 /* 329 * Add in WIG bits 330 */ 331 332 if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_TOLERANT) 333 rflags |= HPTE_R_I; 334 else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_NON_IDEMPOTENT) 335 rflags |= (HPTE_R_I | HPTE_R_G); 336 else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_SAO) 337 rflags |= (HPTE_R_W | HPTE_R_I | HPTE_R_M); 338 else 339 /* 340 * Add memory coherence if cache inhibited is not set 341 */ 342 rflags |= HPTE_R_M; 343 344 rflags |= pte_to_hpte_pkey_bits(pteflags, flags); 345 return rflags; 346 } 347 348 int htab_bolt_mapping(unsigned long vstart, unsigned long vend, 349 unsigned long pstart, unsigned long prot, 350 int psize, int ssize) 351 { 352 unsigned long vaddr, paddr; 353 unsigned int step, shift; 354 int ret = 0; 355 356 shift = mmu_psize_defs[psize].shift; 357 step = 1 << shift; 358 359 prot = htab_convert_pte_flags(prot, HPTE_USE_KERNEL_KEY); 360 361 DBG("htab_bolt_mapping(%lx..%lx -> %lx (%lx,%d,%d)\n", 362 vstart, vend, pstart, prot, psize, ssize); 363 364 /* Carefully map only the possible range */ 365 vaddr = ALIGN(vstart, step); 366 paddr = ALIGN(pstart, step); 367 vend = ALIGN_DOWN(vend, step); 368 369 for (; vaddr < vend; vaddr += step, paddr += step) { 370 unsigned long hash, hpteg; 371 unsigned long vsid = get_kernel_vsid(vaddr, ssize); 372 unsigned long vpn = hpt_vpn(vaddr, vsid, ssize); 373 unsigned long tprot = prot; 374 bool secondary_hash = false; 375 376 /* 377 * If we hit a bad address return error. 378 */ 379 if (!vsid) 380 return -1; 381 /* Make kernel text executable */ 382 if (overlaps_kernel_text(vaddr, vaddr + step)) 383 tprot &= ~HPTE_R_N; 384 385 /* 386 * If relocatable, check if it overlaps interrupt vectors that 387 * are copied down to real 0. For relocatable kernel 388 * (e.g. kdump case) we copy interrupt vectors down to real 389 * address 0. Mark that region as executable. This is 390 * because on p8 system with relocation on exception feature 391 * enabled, exceptions are raised with MMU (IR=DR=1) ON. Hence 392 * in order to execute the interrupt handlers in virtual 393 * mode the vector region need to be marked as executable. 394 */ 395 if ((PHYSICAL_START > MEMORY_START) && 396 overlaps_interrupt_vector_text(vaddr, vaddr + step)) 397 tprot &= ~HPTE_R_N; 398 399 hash = hpt_hash(vpn, shift, ssize); 400 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 401 402 BUG_ON(!mmu_hash_ops.hpte_insert); 403 repeat: 404 ret = mmu_hash_ops.hpte_insert(hpteg, vpn, paddr, tprot, 405 HPTE_V_BOLTED, psize, psize, 406 ssize); 407 if (ret == -1) { 408 /* 409 * Try to to keep bolted entries in primary. 410 * Remove non bolted entries and try insert again 411 */ 412 ret = mmu_hash_ops.hpte_remove(hpteg); 413 if (ret != -1) 414 ret = mmu_hash_ops.hpte_insert(hpteg, vpn, paddr, tprot, 415 HPTE_V_BOLTED, psize, psize, 416 ssize); 417 if (ret == -1 && !secondary_hash) { 418 secondary_hash = true; 419 hpteg = ((~hash & htab_hash_mask) * HPTES_PER_GROUP); 420 goto repeat; 421 } 422 } 423 424 if (ret < 0) 425 break; 426 427 cond_resched(); 428 #ifdef CONFIG_DEBUG_PAGEALLOC 429 if (debug_pagealloc_enabled() && 430 (paddr >> PAGE_SHIFT) < linear_map_hash_count) 431 linear_map_hash_slots[paddr >> PAGE_SHIFT] = ret | 0x80; 432 #endif /* CONFIG_DEBUG_PAGEALLOC */ 433 } 434 return ret < 0 ? ret : 0; 435 } 436 437 int htab_remove_mapping(unsigned long vstart, unsigned long vend, 438 int psize, int ssize) 439 { 440 unsigned long vaddr, time_limit; 441 unsigned int step, shift; 442 int rc; 443 int ret = 0; 444 445 shift = mmu_psize_defs[psize].shift; 446 step = 1 << shift; 447 448 if (!mmu_hash_ops.hpte_removebolted) 449 return -ENODEV; 450 451 /* Unmap the full range specificied */ 452 vaddr = ALIGN_DOWN(vstart, step); 453 time_limit = jiffies + HZ; 454 455 for (;vaddr < vend; vaddr += step) { 456 rc = mmu_hash_ops.hpte_removebolted(vaddr, psize, ssize); 457 458 /* 459 * For large number of mappings introduce a cond_resched() 460 * to prevent softlockup warnings. 461 */ 462 if (time_after(jiffies, time_limit)) { 463 cond_resched(); 464 time_limit = jiffies + HZ; 465 } 466 if (rc == -ENOENT) { 467 ret = -ENOENT; 468 continue; 469 } 470 if (rc < 0) 471 return rc; 472 } 473 474 return ret; 475 } 476 477 static bool disable_1tb_segments = false; 478 479 static int __init parse_disable_1tb_segments(char *p) 480 { 481 disable_1tb_segments = true; 482 return 0; 483 } 484 early_param("disable_1tb_segments", parse_disable_1tb_segments); 485 486 static int __init htab_dt_scan_seg_sizes(unsigned long node, 487 const char *uname, int depth, 488 void *data) 489 { 490 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 491 const __be32 *prop; 492 int size = 0; 493 494 /* We are scanning "cpu" nodes only */ 495 if (type == NULL || strcmp(type, "cpu") != 0) 496 return 0; 497 498 prop = of_get_flat_dt_prop(node, "ibm,processor-segment-sizes", &size); 499 if (prop == NULL) 500 return 0; 501 for (; size >= 4; size -= 4, ++prop) { 502 if (be32_to_cpu(prop[0]) == 40) { 503 DBG("1T segment support detected\n"); 504 505 if (disable_1tb_segments) { 506 DBG("1T segments disabled by command line\n"); 507 break; 508 } 509 510 cur_cpu_spec->mmu_features |= MMU_FTR_1T_SEGMENT; 511 return 1; 512 } 513 } 514 cur_cpu_spec->mmu_features &= ~MMU_FTR_NO_SLBIE_B; 515 return 0; 516 } 517 518 static int __init get_idx_from_shift(unsigned int shift) 519 { 520 int idx = -1; 521 522 switch (shift) { 523 case 0xc: 524 idx = MMU_PAGE_4K; 525 break; 526 case 0x10: 527 idx = MMU_PAGE_64K; 528 break; 529 case 0x14: 530 idx = MMU_PAGE_1M; 531 break; 532 case 0x18: 533 idx = MMU_PAGE_16M; 534 break; 535 case 0x22: 536 idx = MMU_PAGE_16G; 537 break; 538 } 539 return idx; 540 } 541 542 static int __init htab_dt_scan_page_sizes(unsigned long node, 543 const char *uname, int depth, 544 void *data) 545 { 546 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 547 const __be32 *prop; 548 int size = 0; 549 550 /* We are scanning "cpu" nodes only */ 551 if (type == NULL || strcmp(type, "cpu") != 0) 552 return 0; 553 554 prop = of_get_flat_dt_prop(node, "ibm,segment-page-sizes", &size); 555 if (!prop) 556 return 0; 557 558 pr_info("Page sizes from device-tree:\n"); 559 size /= 4; 560 cur_cpu_spec->mmu_features &= ~(MMU_FTR_16M_PAGE); 561 while(size > 0) { 562 unsigned int base_shift = be32_to_cpu(prop[0]); 563 unsigned int slbenc = be32_to_cpu(prop[1]); 564 unsigned int lpnum = be32_to_cpu(prop[2]); 565 struct mmu_psize_def *def; 566 int idx, base_idx; 567 568 size -= 3; prop += 3; 569 base_idx = get_idx_from_shift(base_shift); 570 if (base_idx < 0) { 571 /* skip the pte encoding also */ 572 prop += lpnum * 2; size -= lpnum * 2; 573 continue; 574 } 575 def = &mmu_psize_defs[base_idx]; 576 if (base_idx == MMU_PAGE_16M) 577 cur_cpu_spec->mmu_features |= MMU_FTR_16M_PAGE; 578 579 def->shift = base_shift; 580 if (base_shift <= 23) 581 def->avpnm = 0; 582 else 583 def->avpnm = (1 << (base_shift - 23)) - 1; 584 def->sllp = slbenc; 585 /* 586 * We don't know for sure what's up with tlbiel, so 587 * for now we only set it for 4K and 64K pages 588 */ 589 if (base_idx == MMU_PAGE_4K || base_idx == MMU_PAGE_64K) 590 def->tlbiel = 1; 591 else 592 def->tlbiel = 0; 593 594 while (size > 0 && lpnum) { 595 unsigned int shift = be32_to_cpu(prop[0]); 596 int penc = be32_to_cpu(prop[1]); 597 598 prop += 2; size -= 2; 599 lpnum--; 600 601 idx = get_idx_from_shift(shift); 602 if (idx < 0) 603 continue; 604 605 if (penc == -1) 606 pr_err("Invalid penc for base_shift=%d " 607 "shift=%d\n", base_shift, shift); 608 609 def->penc[idx] = penc; 610 pr_info("base_shift=%d: shift=%d, sllp=0x%04lx," 611 " avpnm=0x%08lx, tlbiel=%d, penc=%d\n", 612 base_shift, shift, def->sllp, 613 def->avpnm, def->tlbiel, def->penc[idx]); 614 } 615 } 616 617 return 1; 618 } 619 620 #ifdef CONFIG_HUGETLB_PAGE 621 /* 622 * Scan for 16G memory blocks that have been set aside for huge pages 623 * and reserve those blocks for 16G huge pages. 624 */ 625 static int __init htab_dt_scan_hugepage_blocks(unsigned long node, 626 const char *uname, int depth, 627 void *data) { 628 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 629 const __be64 *addr_prop; 630 const __be32 *page_count_prop; 631 unsigned int expected_pages; 632 long unsigned int phys_addr; 633 long unsigned int block_size; 634 635 /* We are scanning "memory" nodes only */ 636 if (type == NULL || strcmp(type, "memory") != 0) 637 return 0; 638 639 /* 640 * This property is the log base 2 of the number of virtual pages that 641 * will represent this memory block. 642 */ 643 page_count_prop = of_get_flat_dt_prop(node, "ibm,expected#pages", NULL); 644 if (page_count_prop == NULL) 645 return 0; 646 expected_pages = (1 << be32_to_cpu(page_count_prop[0])); 647 addr_prop = of_get_flat_dt_prop(node, "reg", NULL); 648 if (addr_prop == NULL) 649 return 0; 650 phys_addr = be64_to_cpu(addr_prop[0]); 651 block_size = be64_to_cpu(addr_prop[1]); 652 if (block_size != (16 * GB)) 653 return 0; 654 printk(KERN_INFO "Huge page(16GB) memory: " 655 "addr = 0x%lX size = 0x%lX pages = %d\n", 656 phys_addr, block_size, expected_pages); 657 if (phys_addr + block_size * expected_pages <= memblock_end_of_DRAM()) { 658 memblock_reserve(phys_addr, block_size * expected_pages); 659 pseries_add_gpage(phys_addr, block_size, expected_pages); 660 } 661 return 0; 662 } 663 #endif /* CONFIG_HUGETLB_PAGE */ 664 665 static void __init mmu_psize_set_default_penc(void) 666 { 667 int bpsize, apsize; 668 for (bpsize = 0; bpsize < MMU_PAGE_COUNT; bpsize++) 669 for (apsize = 0; apsize < MMU_PAGE_COUNT; apsize++) 670 mmu_psize_defs[bpsize].penc[apsize] = -1; 671 } 672 673 #ifdef CONFIG_PPC_64K_PAGES 674 675 static bool __init might_have_hea(void) 676 { 677 /* 678 * The HEA ethernet adapter requires awareness of the 679 * GX bus. Without that awareness we can easily assume 680 * we will never see an HEA ethernet device. 681 */ 682 #ifdef CONFIG_IBMEBUS 683 return !cpu_has_feature(CPU_FTR_ARCH_207S) && 684 firmware_has_feature(FW_FEATURE_SPLPAR); 685 #else 686 return false; 687 #endif 688 } 689 690 #endif /* #ifdef CONFIG_PPC_64K_PAGES */ 691 692 static void __init htab_scan_page_sizes(void) 693 { 694 int rc; 695 696 /* se the invalid penc to -1 */ 697 mmu_psize_set_default_penc(); 698 699 /* Default to 4K pages only */ 700 memcpy(mmu_psize_defs, mmu_psize_defaults, 701 sizeof(mmu_psize_defaults)); 702 703 /* 704 * Try to find the available page sizes in the device-tree 705 */ 706 rc = of_scan_flat_dt(htab_dt_scan_page_sizes, NULL); 707 if (rc == 0 && early_mmu_has_feature(MMU_FTR_16M_PAGE)) { 708 /* 709 * Nothing in the device-tree, but the CPU supports 16M pages, 710 * so let's fallback on a known size list for 16M capable CPUs. 711 */ 712 memcpy(mmu_psize_defs, mmu_psize_defaults_gp, 713 sizeof(mmu_psize_defaults_gp)); 714 } 715 716 #ifdef CONFIG_HUGETLB_PAGE 717 if (!hugetlb_disabled && !early_radix_enabled() ) { 718 /* Reserve 16G huge page memory sections for huge pages */ 719 of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL); 720 } 721 #endif /* CONFIG_HUGETLB_PAGE */ 722 } 723 724 /* 725 * Fill in the hpte_page_sizes[] array. 726 * We go through the mmu_psize_defs[] array looking for all the 727 * supported base/actual page size combinations. Each combination 728 * has a unique pagesize encoding (penc) value in the low bits of 729 * the LP field of the HPTE. For actual page sizes less than 1MB, 730 * some of the upper LP bits are used for RPN bits, meaning that 731 * we need to fill in several entries in hpte_page_sizes[]. 732 * 733 * In diagrammatic form, with r = RPN bits and z = page size bits: 734 * PTE LP actual page size 735 * rrrr rrrz >=8KB 736 * rrrr rrzz >=16KB 737 * rrrr rzzz >=32KB 738 * rrrr zzzz >=64KB 739 * ... 740 * 741 * The zzzz bits are implementation-specific but are chosen so that 742 * no encoding for a larger page size uses the same value in its 743 * low-order N bits as the encoding for the 2^(12+N) byte page size 744 * (if it exists). 745 */ 746 static void __init init_hpte_page_sizes(void) 747 { 748 long int ap, bp; 749 long int shift, penc; 750 751 for (bp = 0; bp < MMU_PAGE_COUNT; ++bp) { 752 if (!mmu_psize_defs[bp].shift) 753 continue; /* not a supported page size */ 754 for (ap = bp; ap < MMU_PAGE_COUNT; ++ap) { 755 penc = mmu_psize_defs[bp].penc[ap]; 756 if (penc == -1 || !mmu_psize_defs[ap].shift) 757 continue; 758 shift = mmu_psize_defs[ap].shift - LP_SHIFT; 759 if (shift <= 0) 760 continue; /* should never happen */ 761 /* 762 * For page sizes less than 1MB, this loop 763 * replicates the entry for all possible values 764 * of the rrrr bits. 765 */ 766 while (penc < (1 << LP_BITS)) { 767 hpte_page_sizes[penc] = (ap << 4) | bp; 768 penc += 1 << shift; 769 } 770 } 771 } 772 } 773 774 static void __init htab_init_page_sizes(void) 775 { 776 bool aligned = true; 777 init_hpte_page_sizes(); 778 779 if (!debug_pagealloc_enabled()) { 780 /* 781 * Pick a size for the linear mapping. Currently, we only 782 * support 16M, 1M and 4K which is the default 783 */ 784 if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && 785 (unsigned long)_stext % 0x1000000) { 786 if (mmu_psize_defs[MMU_PAGE_16M].shift) 787 pr_warn("Kernel not 16M aligned, disabling 16M linear map alignment\n"); 788 aligned = false; 789 } 790 791 if (mmu_psize_defs[MMU_PAGE_16M].shift && aligned) 792 mmu_linear_psize = MMU_PAGE_16M; 793 else if (mmu_psize_defs[MMU_PAGE_1M].shift) 794 mmu_linear_psize = MMU_PAGE_1M; 795 } 796 797 #ifdef CONFIG_PPC_64K_PAGES 798 /* 799 * Pick a size for the ordinary pages. Default is 4K, we support 800 * 64K for user mappings and vmalloc if supported by the processor. 801 * We only use 64k for ioremap if the processor 802 * (and firmware) support cache-inhibited large pages. 803 * If not, we use 4k and set mmu_ci_restrictions so that 804 * hash_page knows to switch processes that use cache-inhibited 805 * mappings to 4k pages. 806 */ 807 if (mmu_psize_defs[MMU_PAGE_64K].shift) { 808 mmu_virtual_psize = MMU_PAGE_64K; 809 mmu_vmalloc_psize = MMU_PAGE_64K; 810 if (mmu_linear_psize == MMU_PAGE_4K) 811 mmu_linear_psize = MMU_PAGE_64K; 812 if (mmu_has_feature(MMU_FTR_CI_LARGE_PAGE)) { 813 /* 814 * When running on pSeries using 64k pages for ioremap 815 * would stop us accessing the HEA ethernet. So if we 816 * have the chance of ever seeing one, stay at 4k. 817 */ 818 if (!might_have_hea()) 819 mmu_io_psize = MMU_PAGE_64K; 820 } else 821 mmu_ci_restrictions = 1; 822 } 823 #endif /* CONFIG_PPC_64K_PAGES */ 824 825 #ifdef CONFIG_SPARSEMEM_VMEMMAP 826 /* 827 * We try to use 16M pages for vmemmap if that is supported 828 * and we have at least 1G of RAM at boot 829 */ 830 if (mmu_psize_defs[MMU_PAGE_16M].shift && 831 memblock_phys_mem_size() >= 0x40000000) 832 mmu_vmemmap_psize = MMU_PAGE_16M; 833 else 834 mmu_vmemmap_psize = mmu_virtual_psize; 835 #endif /* CONFIG_SPARSEMEM_VMEMMAP */ 836 837 printk(KERN_DEBUG "Page orders: linear mapping = %d, " 838 "virtual = %d, io = %d" 839 #ifdef CONFIG_SPARSEMEM_VMEMMAP 840 ", vmemmap = %d" 841 #endif 842 "\n", 843 mmu_psize_defs[mmu_linear_psize].shift, 844 mmu_psize_defs[mmu_virtual_psize].shift, 845 mmu_psize_defs[mmu_io_psize].shift 846 #ifdef CONFIG_SPARSEMEM_VMEMMAP 847 ,mmu_psize_defs[mmu_vmemmap_psize].shift 848 #endif 849 ); 850 } 851 852 static int __init htab_dt_scan_pftsize(unsigned long node, 853 const char *uname, int depth, 854 void *data) 855 { 856 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 857 const __be32 *prop; 858 859 /* We are scanning "cpu" nodes only */ 860 if (type == NULL || strcmp(type, "cpu") != 0) 861 return 0; 862 863 prop = of_get_flat_dt_prop(node, "ibm,pft-size", NULL); 864 if (prop != NULL) { 865 /* pft_size[0] is the NUMA CEC cookie */ 866 ppc64_pft_size = be32_to_cpu(prop[1]); 867 return 1; 868 } 869 return 0; 870 } 871 872 unsigned htab_shift_for_mem_size(unsigned long mem_size) 873 { 874 unsigned memshift = __ilog2(mem_size); 875 unsigned pshift = mmu_psize_defs[mmu_virtual_psize].shift; 876 unsigned pteg_shift; 877 878 /* round mem_size up to next power of 2 */ 879 if ((1UL << memshift) < mem_size) 880 memshift += 1; 881 882 /* aim for 2 pages / pteg */ 883 pteg_shift = memshift - (pshift + 1); 884 885 /* 886 * 2^11 PTEGS of 128 bytes each, ie. 2^18 bytes is the minimum htab 887 * size permitted by the architecture. 888 */ 889 return max(pteg_shift + 7, 18U); 890 } 891 892 static unsigned long __init htab_get_table_size(void) 893 { 894 /* 895 * If hash size isn't already provided by the platform, we try to 896 * retrieve it from the device-tree. If it's not there neither, we 897 * calculate it now based on the total RAM size 898 */ 899 if (ppc64_pft_size == 0) 900 of_scan_flat_dt(htab_dt_scan_pftsize, NULL); 901 if (ppc64_pft_size) 902 return 1UL << ppc64_pft_size; 903 904 return 1UL << htab_shift_for_mem_size(memblock_phys_mem_size()); 905 } 906 907 #ifdef CONFIG_MEMORY_HOTPLUG 908 static int resize_hpt_for_hotplug(unsigned long new_mem_size) 909 { 910 unsigned target_hpt_shift; 911 912 if (!mmu_hash_ops.resize_hpt) 913 return 0; 914 915 target_hpt_shift = htab_shift_for_mem_size(new_mem_size); 916 917 /* 918 * To avoid lots of HPT resizes if memory size is fluctuating 919 * across a boundary, we deliberately have some hysterisis 920 * here: we immediately increase the HPT size if the target 921 * shift exceeds the current shift, but we won't attempt to 922 * reduce unless the target shift is at least 2 below the 923 * current shift 924 */ 925 if (target_hpt_shift > ppc64_pft_size || 926 target_hpt_shift < ppc64_pft_size - 1) 927 return mmu_hash_ops.resize_hpt(target_hpt_shift); 928 929 return 0; 930 } 931 932 int hash__create_section_mapping(unsigned long start, unsigned long end, 933 int nid, pgprot_t prot) 934 { 935 int rc; 936 937 if (end >= H_VMALLOC_START) { 938 pr_warn("Outside the supported range\n"); 939 return -1; 940 } 941 942 resize_hpt_for_hotplug(memblock_phys_mem_size()); 943 944 rc = htab_bolt_mapping(start, end, __pa(start), 945 pgprot_val(prot), mmu_linear_psize, 946 mmu_kernel_ssize); 947 948 if (rc < 0) { 949 int rc2 = htab_remove_mapping(start, end, mmu_linear_psize, 950 mmu_kernel_ssize); 951 BUG_ON(rc2 && (rc2 != -ENOENT)); 952 } 953 return rc; 954 } 955 956 int hash__remove_section_mapping(unsigned long start, unsigned long end) 957 { 958 int rc = htab_remove_mapping(start, end, mmu_linear_psize, 959 mmu_kernel_ssize); 960 961 if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC) 962 pr_warn("Hash collision while resizing HPT\n"); 963 964 return rc; 965 } 966 #endif /* CONFIG_MEMORY_HOTPLUG */ 967 968 static void __init hash_init_partition_table(phys_addr_t hash_table, 969 unsigned long htab_size) 970 { 971 mmu_partition_table_init(); 972 973 /* 974 * PS field (VRMA page size) is not used for LPID 0, hence set to 0. 975 * For now, UPRT is 0 and we have no segment table. 976 */ 977 htab_size = __ilog2(htab_size) - 18; 978 mmu_partition_table_set_entry(0, hash_table | htab_size, 0, false); 979 pr_info("Partition table %p\n", partition_tb); 980 } 981 982 static void __init htab_initialize(void) 983 { 984 unsigned long table; 985 unsigned long pteg_count; 986 unsigned long prot; 987 phys_addr_t base = 0, size = 0, end; 988 u64 i; 989 990 DBG(" -> htab_initialize()\n"); 991 992 if (mmu_has_feature(MMU_FTR_1T_SEGMENT)) { 993 mmu_kernel_ssize = MMU_SEGSIZE_1T; 994 mmu_highuser_ssize = MMU_SEGSIZE_1T; 995 printk(KERN_INFO "Using 1TB segments\n"); 996 } 997 998 if (stress_slb_enabled) 999 static_branch_enable(&stress_slb_key); 1000 1001 /* 1002 * Calculate the required size of the htab. We want the number of 1003 * PTEGs to equal one half the number of real pages. 1004 */ 1005 htab_size_bytes = htab_get_table_size(); 1006 pteg_count = htab_size_bytes >> 7; 1007 1008 htab_hash_mask = pteg_count - 1; 1009 1010 if (firmware_has_feature(FW_FEATURE_LPAR) || 1011 firmware_has_feature(FW_FEATURE_PS3_LV1)) { 1012 /* Using a hypervisor which owns the htab */ 1013 htab_address = NULL; 1014 _SDR1 = 0; 1015 #ifdef CONFIG_FA_DUMP 1016 /* 1017 * If firmware assisted dump is active firmware preserves 1018 * the contents of htab along with entire partition memory. 1019 * Clear the htab if firmware assisted dump is active so 1020 * that we dont end up using old mappings. 1021 */ 1022 if (is_fadump_active() && mmu_hash_ops.hpte_clear_all) 1023 mmu_hash_ops.hpte_clear_all(); 1024 #endif 1025 } else { 1026 unsigned long limit = MEMBLOCK_ALLOC_ANYWHERE; 1027 1028 #ifdef CONFIG_PPC_CELL 1029 /* 1030 * Cell may require the hash table down low when using the 1031 * Axon IOMMU in order to fit the dynamic region over it, see 1032 * comments in cell/iommu.c 1033 */ 1034 if (fdt_subnode_offset(initial_boot_params, 0, "axon") > 0) { 1035 limit = 0x80000000; 1036 pr_info("Hash table forced below 2G for Axon IOMMU\n"); 1037 } 1038 #endif /* CONFIG_PPC_CELL */ 1039 1040 table = memblock_phys_alloc_range(htab_size_bytes, 1041 htab_size_bytes, 1042 0, limit); 1043 if (!table) 1044 panic("ERROR: Failed to allocate %pa bytes below %pa\n", 1045 &htab_size_bytes, &limit); 1046 1047 DBG("Hash table allocated at %lx, size: %lx\n", table, 1048 htab_size_bytes); 1049 1050 htab_address = __va(table); 1051 1052 /* htab absolute addr + encoded htabsize */ 1053 _SDR1 = table + __ilog2(htab_size_bytes) - 18; 1054 1055 /* Initialize the HPT with no entries */ 1056 memset((void *)table, 0, htab_size_bytes); 1057 1058 if (!cpu_has_feature(CPU_FTR_ARCH_300)) 1059 /* Set SDR1 */ 1060 mtspr(SPRN_SDR1, _SDR1); 1061 else 1062 hash_init_partition_table(table, htab_size_bytes); 1063 } 1064 1065 prot = pgprot_val(PAGE_KERNEL); 1066 1067 #ifdef CONFIG_DEBUG_PAGEALLOC 1068 if (debug_pagealloc_enabled()) { 1069 linear_map_hash_count = memblock_end_of_DRAM() >> PAGE_SHIFT; 1070 linear_map_hash_slots = memblock_alloc_try_nid( 1071 linear_map_hash_count, 1, MEMBLOCK_LOW_LIMIT, 1072 ppc64_rma_size, NUMA_NO_NODE); 1073 if (!linear_map_hash_slots) 1074 panic("%s: Failed to allocate %lu bytes max_addr=%pa\n", 1075 __func__, linear_map_hash_count, &ppc64_rma_size); 1076 } 1077 #endif /* CONFIG_DEBUG_PAGEALLOC */ 1078 1079 /* create bolted the linear mapping in the hash table */ 1080 for_each_mem_range(i, &base, &end) { 1081 size = end - base; 1082 base = (unsigned long)__va(base); 1083 1084 DBG("creating mapping for region: %lx..%lx (prot: %lx)\n", 1085 base, size, prot); 1086 1087 if ((base + size) >= H_VMALLOC_START) { 1088 pr_warn("Outside the supported range\n"); 1089 continue; 1090 } 1091 1092 BUG_ON(htab_bolt_mapping(base, base + size, __pa(base), 1093 prot, mmu_linear_psize, mmu_kernel_ssize)); 1094 } 1095 memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE); 1096 1097 /* 1098 * If we have a memory_limit and we've allocated TCEs then we need to 1099 * explicitly map the TCE area at the top of RAM. We also cope with the 1100 * case that the TCEs start below memory_limit. 1101 * tce_alloc_start/end are 16MB aligned so the mapping should work 1102 * for either 4K or 16MB pages. 1103 */ 1104 if (tce_alloc_start) { 1105 tce_alloc_start = (unsigned long)__va(tce_alloc_start); 1106 tce_alloc_end = (unsigned long)__va(tce_alloc_end); 1107 1108 if (base + size >= tce_alloc_start) 1109 tce_alloc_start = base + size + 1; 1110 1111 BUG_ON(htab_bolt_mapping(tce_alloc_start, tce_alloc_end, 1112 __pa(tce_alloc_start), prot, 1113 mmu_linear_psize, mmu_kernel_ssize)); 1114 } 1115 1116 1117 DBG(" <- htab_initialize()\n"); 1118 } 1119 #undef KB 1120 #undef MB 1121 1122 void __init hash__early_init_devtree(void) 1123 { 1124 /* Initialize segment sizes */ 1125 of_scan_flat_dt(htab_dt_scan_seg_sizes, NULL); 1126 1127 /* Initialize page sizes */ 1128 htab_scan_page_sizes(); 1129 } 1130 1131 static struct hash_mm_context init_hash_mm_context; 1132 void __init hash__early_init_mmu(void) 1133 { 1134 #ifndef CONFIG_PPC_64K_PAGES 1135 /* 1136 * We have code in __hash_page_4K() and elsewhere, which assumes it can 1137 * do the following: 1138 * new_pte |= (slot << H_PAGE_F_GIX_SHIFT) & (H_PAGE_F_SECOND | H_PAGE_F_GIX); 1139 * 1140 * Where the slot number is between 0-15, and values of 8-15 indicate 1141 * the secondary bucket. For that code to work H_PAGE_F_SECOND and 1142 * H_PAGE_F_GIX must occupy four contiguous bits in the PTE, and 1143 * H_PAGE_F_SECOND must be placed above H_PAGE_F_GIX. Assert that here 1144 * with a BUILD_BUG_ON(). 1145 */ 1146 BUILD_BUG_ON(H_PAGE_F_SECOND != (1ul << (H_PAGE_F_GIX_SHIFT + 3))); 1147 #endif /* CONFIG_PPC_64K_PAGES */ 1148 1149 htab_init_page_sizes(); 1150 1151 /* 1152 * initialize page table size 1153 */ 1154 __pte_frag_nr = H_PTE_FRAG_NR; 1155 __pte_frag_size_shift = H_PTE_FRAG_SIZE_SHIFT; 1156 __pmd_frag_nr = H_PMD_FRAG_NR; 1157 __pmd_frag_size_shift = H_PMD_FRAG_SIZE_SHIFT; 1158 1159 __pte_index_size = H_PTE_INDEX_SIZE; 1160 __pmd_index_size = H_PMD_INDEX_SIZE; 1161 __pud_index_size = H_PUD_INDEX_SIZE; 1162 __pgd_index_size = H_PGD_INDEX_SIZE; 1163 __pud_cache_index = H_PUD_CACHE_INDEX; 1164 __pte_table_size = H_PTE_TABLE_SIZE; 1165 __pmd_table_size = H_PMD_TABLE_SIZE; 1166 __pud_table_size = H_PUD_TABLE_SIZE; 1167 __pgd_table_size = H_PGD_TABLE_SIZE; 1168 /* 1169 * 4k use hugepd format, so for hash set then to 1170 * zero 1171 */ 1172 __pmd_val_bits = HASH_PMD_VAL_BITS; 1173 __pud_val_bits = HASH_PUD_VAL_BITS; 1174 __pgd_val_bits = HASH_PGD_VAL_BITS; 1175 1176 __kernel_virt_start = H_KERN_VIRT_START; 1177 __vmalloc_start = H_VMALLOC_START; 1178 __vmalloc_end = H_VMALLOC_END; 1179 __kernel_io_start = H_KERN_IO_START; 1180 __kernel_io_end = H_KERN_IO_END; 1181 vmemmap = (struct page *)H_VMEMMAP_START; 1182 ioremap_bot = IOREMAP_BASE; 1183 1184 #ifdef CONFIG_PCI 1185 pci_io_base = ISA_IO_BASE; 1186 #endif 1187 1188 /* Select appropriate backend */ 1189 if (firmware_has_feature(FW_FEATURE_PS3_LV1)) 1190 ps3_early_mm_init(); 1191 else if (firmware_has_feature(FW_FEATURE_LPAR)) 1192 hpte_init_pseries(); 1193 else if (IS_ENABLED(CONFIG_PPC_HASH_MMU_NATIVE)) 1194 hpte_init_native(); 1195 1196 if (!mmu_hash_ops.hpte_insert) 1197 panic("hash__early_init_mmu: No MMU hash ops defined!\n"); 1198 1199 /* 1200 * Initialize the MMU Hash table and create the linear mapping 1201 * of memory. Has to be done before SLB initialization as this is 1202 * currently where the page size encoding is obtained. 1203 */ 1204 htab_initialize(); 1205 1206 init_mm.context.hash_context = &init_hash_mm_context; 1207 mm_ctx_set_slb_addr_limit(&init_mm.context, SLB_ADDR_LIMIT_DEFAULT); 1208 1209 pr_info("Initializing hash mmu with SLB\n"); 1210 /* Initialize SLB management */ 1211 slb_initialize(); 1212 1213 if (cpu_has_feature(CPU_FTR_ARCH_206) 1214 && cpu_has_feature(CPU_FTR_HVMODE)) 1215 tlbiel_all(); 1216 } 1217 1218 #ifdef CONFIG_SMP 1219 void hash__early_init_mmu_secondary(void) 1220 { 1221 /* Initialize hash table for that CPU */ 1222 if (!firmware_has_feature(FW_FEATURE_LPAR)) { 1223 1224 if (!cpu_has_feature(CPU_FTR_ARCH_300)) 1225 mtspr(SPRN_SDR1, _SDR1); 1226 else 1227 set_ptcr_when_no_uv(__pa(partition_tb) | 1228 (PATB_SIZE_SHIFT - 12)); 1229 } 1230 /* Initialize SLB */ 1231 slb_initialize(); 1232 1233 if (cpu_has_feature(CPU_FTR_ARCH_206) 1234 && cpu_has_feature(CPU_FTR_HVMODE)) 1235 tlbiel_all(); 1236 1237 #ifdef CONFIG_PPC_MEM_KEYS 1238 if (mmu_has_feature(MMU_FTR_PKEY)) 1239 mtspr(SPRN_UAMOR, default_uamor); 1240 #endif 1241 } 1242 #endif /* CONFIG_SMP */ 1243 1244 /* 1245 * Called by asm hashtable.S for doing lazy icache flush 1246 */ 1247 unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap) 1248 { 1249 struct page *page; 1250 1251 if (!pfn_valid(pte_pfn(pte))) 1252 return pp; 1253 1254 page = pte_page(pte); 1255 1256 /* page is dirty */ 1257 if (!test_bit(PG_dcache_clean, &page->flags) && !PageReserved(page)) { 1258 if (trap == INTERRUPT_INST_STORAGE) { 1259 flush_dcache_icache_page(page); 1260 set_bit(PG_dcache_clean, &page->flags); 1261 } else 1262 pp |= HPTE_R_N; 1263 } 1264 return pp; 1265 } 1266 1267 #ifdef CONFIG_PPC_MM_SLICES 1268 static unsigned int get_paca_psize(unsigned long addr) 1269 { 1270 unsigned char *psizes; 1271 unsigned long index, mask_index; 1272 1273 if (addr < SLICE_LOW_TOP) { 1274 psizes = get_paca()->mm_ctx_low_slices_psize; 1275 index = GET_LOW_SLICE_INDEX(addr); 1276 } else { 1277 psizes = get_paca()->mm_ctx_high_slices_psize; 1278 index = GET_HIGH_SLICE_INDEX(addr); 1279 } 1280 mask_index = index & 0x1; 1281 return (psizes[index >> 1] >> (mask_index * 4)) & 0xF; 1282 } 1283 1284 #else 1285 unsigned int get_paca_psize(unsigned long addr) 1286 { 1287 return get_paca()->mm_ctx_user_psize; 1288 } 1289 #endif 1290 1291 /* 1292 * Demote a segment to using 4k pages. 1293 * For now this makes the whole process use 4k pages. 1294 */ 1295 #ifdef CONFIG_PPC_64K_PAGES 1296 void demote_segment_4k(struct mm_struct *mm, unsigned long addr) 1297 { 1298 if (get_slice_psize(mm, addr) == MMU_PAGE_4K) 1299 return; 1300 slice_set_range_psize(mm, addr, 1, MMU_PAGE_4K); 1301 copro_flush_all_slbs(mm); 1302 if ((get_paca_psize(addr) != MMU_PAGE_4K) && (current->mm == mm)) { 1303 1304 copy_mm_to_paca(mm); 1305 slb_flush_and_restore_bolted(); 1306 } 1307 } 1308 #endif /* CONFIG_PPC_64K_PAGES */ 1309 1310 #ifdef CONFIG_PPC_SUBPAGE_PROT 1311 /* 1312 * This looks up a 2-bit protection code for a 4k subpage of a 64k page. 1313 * Userspace sets the subpage permissions using the subpage_prot system call. 1314 * 1315 * Result is 0: full permissions, _PAGE_RW: read-only, 1316 * _PAGE_RWX: no access. 1317 */ 1318 static int subpage_protection(struct mm_struct *mm, unsigned long ea) 1319 { 1320 struct subpage_prot_table *spt = mm_ctx_subpage_prot(&mm->context); 1321 u32 spp = 0; 1322 u32 **sbpm, *sbpp; 1323 1324 if (!spt) 1325 return 0; 1326 1327 if (ea >= spt->maxaddr) 1328 return 0; 1329 if (ea < 0x100000000UL) { 1330 /* addresses below 4GB use spt->low_prot */ 1331 sbpm = spt->low_prot; 1332 } else { 1333 sbpm = spt->protptrs[ea >> SBP_L3_SHIFT]; 1334 if (!sbpm) 1335 return 0; 1336 } 1337 sbpp = sbpm[(ea >> SBP_L2_SHIFT) & (SBP_L2_COUNT - 1)]; 1338 if (!sbpp) 1339 return 0; 1340 spp = sbpp[(ea >> PAGE_SHIFT) & (SBP_L1_COUNT - 1)]; 1341 1342 /* extract 2-bit bitfield for this 4k subpage */ 1343 spp >>= 30 - 2 * ((ea >> 12) & 0xf); 1344 1345 /* 1346 * 0 -> full premission 1347 * 1 -> Read only 1348 * 2 -> no access. 1349 * We return the flag that need to be cleared. 1350 */ 1351 spp = ((spp & 2) ? _PAGE_RWX : 0) | ((spp & 1) ? _PAGE_WRITE : 0); 1352 return spp; 1353 } 1354 1355 #else /* CONFIG_PPC_SUBPAGE_PROT */ 1356 static inline int subpage_protection(struct mm_struct *mm, unsigned long ea) 1357 { 1358 return 0; 1359 } 1360 #endif 1361 1362 void hash_failure_debug(unsigned long ea, unsigned long access, 1363 unsigned long vsid, unsigned long trap, 1364 int ssize, int psize, int lpsize, unsigned long pte) 1365 { 1366 if (!printk_ratelimit()) 1367 return; 1368 pr_info("mm: Hashing failure ! EA=0x%lx access=0x%lx current=%s\n", 1369 ea, access, current->comm); 1370 pr_info(" trap=0x%lx vsid=0x%lx ssize=%d base psize=%d psize %d pte=0x%lx\n", 1371 trap, vsid, ssize, psize, lpsize, pte); 1372 } 1373 1374 static void check_paca_psize(unsigned long ea, struct mm_struct *mm, 1375 int psize, bool user_region) 1376 { 1377 if (user_region) { 1378 if (psize != get_paca_psize(ea)) { 1379 copy_mm_to_paca(mm); 1380 slb_flush_and_restore_bolted(); 1381 } 1382 } else if (get_paca()->vmalloc_sllp != 1383 mmu_psize_defs[mmu_vmalloc_psize].sllp) { 1384 get_paca()->vmalloc_sllp = 1385 mmu_psize_defs[mmu_vmalloc_psize].sllp; 1386 slb_vmalloc_update(); 1387 } 1388 } 1389 1390 /* 1391 * Result code is: 1392 * 0 - handled 1393 * 1 - normal page fault 1394 * -1 - critical hash insertion error 1395 * -2 - access not permitted by subpage protection mechanism 1396 */ 1397 int hash_page_mm(struct mm_struct *mm, unsigned long ea, 1398 unsigned long access, unsigned long trap, 1399 unsigned long flags) 1400 { 1401 bool is_thp; 1402 pgd_t *pgdir; 1403 unsigned long vsid; 1404 pte_t *ptep; 1405 unsigned hugeshift; 1406 int rc, user_region = 0; 1407 int psize, ssize; 1408 1409 DBG_LOW("hash_page(ea=%016lx, access=%lx, trap=%lx\n", 1410 ea, access, trap); 1411 trace_hash_fault(ea, access, trap); 1412 1413 /* Get region & vsid */ 1414 switch (get_region_id(ea)) { 1415 case USER_REGION_ID: 1416 user_region = 1; 1417 if (! mm) { 1418 DBG_LOW(" user region with no mm !\n"); 1419 rc = 1; 1420 goto bail; 1421 } 1422 psize = get_slice_psize(mm, ea); 1423 ssize = user_segment_size(ea); 1424 vsid = get_user_vsid(&mm->context, ea, ssize); 1425 break; 1426 case VMALLOC_REGION_ID: 1427 vsid = get_kernel_vsid(ea, mmu_kernel_ssize); 1428 psize = mmu_vmalloc_psize; 1429 ssize = mmu_kernel_ssize; 1430 flags |= HPTE_USE_KERNEL_KEY; 1431 break; 1432 1433 case IO_REGION_ID: 1434 vsid = get_kernel_vsid(ea, mmu_kernel_ssize); 1435 psize = mmu_io_psize; 1436 ssize = mmu_kernel_ssize; 1437 flags |= HPTE_USE_KERNEL_KEY; 1438 break; 1439 default: 1440 /* 1441 * Not a valid range 1442 * Send the problem up to do_page_fault() 1443 */ 1444 rc = 1; 1445 goto bail; 1446 } 1447 DBG_LOW(" mm=%p, mm->pgdir=%p, vsid=%016lx\n", mm, mm->pgd, vsid); 1448 1449 /* Bad address. */ 1450 if (!vsid) { 1451 DBG_LOW("Bad address!\n"); 1452 rc = 1; 1453 goto bail; 1454 } 1455 /* Get pgdir */ 1456 pgdir = mm->pgd; 1457 if (pgdir == NULL) { 1458 rc = 1; 1459 goto bail; 1460 } 1461 1462 /* Check CPU locality */ 1463 if (user_region && mm_is_thread_local(mm)) 1464 flags |= HPTE_LOCAL_UPDATE; 1465 1466 #ifndef CONFIG_PPC_64K_PAGES 1467 /* 1468 * If we use 4K pages and our psize is not 4K, then we might 1469 * be hitting a special driver mapping, and need to align the 1470 * address before we fetch the PTE. 1471 * 1472 * It could also be a hugepage mapping, in which case this is 1473 * not necessary, but it's not harmful, either. 1474 */ 1475 if (psize != MMU_PAGE_4K) 1476 ea &= ~((1ul << mmu_psize_defs[psize].shift) - 1); 1477 #endif /* CONFIG_PPC_64K_PAGES */ 1478 1479 /* Get PTE and page size from page tables */ 1480 ptep = find_linux_pte(pgdir, ea, &is_thp, &hugeshift); 1481 if (ptep == NULL || !pte_present(*ptep)) { 1482 DBG_LOW(" no PTE !\n"); 1483 rc = 1; 1484 goto bail; 1485 } 1486 1487 /* 1488 * Add _PAGE_PRESENT to the required access perm. If there are parallel 1489 * updates to the pte that can possibly clear _PAGE_PTE, catch that too. 1490 * 1491 * We can safely use the return pte address in rest of the function 1492 * because we do set H_PAGE_BUSY which prevents further updates to pte 1493 * from generic code. 1494 */ 1495 access |= _PAGE_PRESENT | _PAGE_PTE; 1496 1497 /* 1498 * Pre-check access permissions (will be re-checked atomically 1499 * in __hash_page_XX but this pre-check is a fast path 1500 */ 1501 if (!check_pte_access(access, pte_val(*ptep))) { 1502 DBG_LOW(" no access !\n"); 1503 rc = 1; 1504 goto bail; 1505 } 1506 1507 if (hugeshift) { 1508 if (is_thp) 1509 rc = __hash_page_thp(ea, access, vsid, (pmd_t *)ptep, 1510 trap, flags, ssize, psize); 1511 #ifdef CONFIG_HUGETLB_PAGE 1512 else 1513 rc = __hash_page_huge(ea, access, vsid, ptep, trap, 1514 flags, ssize, hugeshift, psize); 1515 #else 1516 else { 1517 /* 1518 * if we have hugeshift, and is not transhuge with 1519 * hugetlb disabled, something is really wrong. 1520 */ 1521 rc = 1; 1522 WARN_ON(1); 1523 } 1524 #endif 1525 if (current->mm == mm) 1526 check_paca_psize(ea, mm, psize, user_region); 1527 1528 goto bail; 1529 } 1530 1531 #ifndef CONFIG_PPC_64K_PAGES 1532 DBG_LOW(" i-pte: %016lx\n", pte_val(*ptep)); 1533 #else 1534 DBG_LOW(" i-pte: %016lx %016lx\n", pte_val(*ptep), 1535 pte_val(*(ptep + PTRS_PER_PTE))); 1536 #endif 1537 /* Do actual hashing */ 1538 #ifdef CONFIG_PPC_64K_PAGES 1539 /* If H_PAGE_4K_PFN is set, make sure this is a 4k segment */ 1540 if ((pte_val(*ptep) & H_PAGE_4K_PFN) && psize == MMU_PAGE_64K) { 1541 demote_segment_4k(mm, ea); 1542 psize = MMU_PAGE_4K; 1543 } 1544 1545 /* 1546 * If this PTE is non-cacheable and we have restrictions on 1547 * using non cacheable large pages, then we switch to 4k 1548 */ 1549 if (mmu_ci_restrictions && psize == MMU_PAGE_64K && pte_ci(*ptep)) { 1550 if (user_region) { 1551 demote_segment_4k(mm, ea); 1552 psize = MMU_PAGE_4K; 1553 } else if (ea < VMALLOC_END) { 1554 /* 1555 * some driver did a non-cacheable mapping 1556 * in vmalloc space, so switch vmalloc 1557 * to 4k pages 1558 */ 1559 printk(KERN_ALERT "Reducing vmalloc segment " 1560 "to 4kB pages because of " 1561 "non-cacheable mapping\n"); 1562 psize = mmu_vmalloc_psize = MMU_PAGE_4K; 1563 copro_flush_all_slbs(mm); 1564 } 1565 } 1566 1567 #endif /* CONFIG_PPC_64K_PAGES */ 1568 1569 if (current->mm == mm) 1570 check_paca_psize(ea, mm, psize, user_region); 1571 1572 #ifdef CONFIG_PPC_64K_PAGES 1573 if (psize == MMU_PAGE_64K) 1574 rc = __hash_page_64K(ea, access, vsid, ptep, trap, 1575 flags, ssize); 1576 else 1577 #endif /* CONFIG_PPC_64K_PAGES */ 1578 { 1579 int spp = subpage_protection(mm, ea); 1580 if (access & spp) 1581 rc = -2; 1582 else 1583 rc = __hash_page_4K(ea, access, vsid, ptep, trap, 1584 flags, ssize, spp); 1585 } 1586 1587 /* 1588 * Dump some info in case of hash insertion failure, they should 1589 * never happen so it is really useful to know if/when they do 1590 */ 1591 if (rc == -1) 1592 hash_failure_debug(ea, access, vsid, trap, ssize, psize, 1593 psize, pte_val(*ptep)); 1594 #ifndef CONFIG_PPC_64K_PAGES 1595 DBG_LOW(" o-pte: %016lx\n", pte_val(*ptep)); 1596 #else 1597 DBG_LOW(" o-pte: %016lx %016lx\n", pte_val(*ptep), 1598 pte_val(*(ptep + PTRS_PER_PTE))); 1599 #endif 1600 DBG_LOW(" -> rc=%d\n", rc); 1601 1602 bail: 1603 return rc; 1604 } 1605 EXPORT_SYMBOL_GPL(hash_page_mm); 1606 1607 int hash_page(unsigned long ea, unsigned long access, unsigned long trap, 1608 unsigned long dsisr) 1609 { 1610 unsigned long flags = 0; 1611 struct mm_struct *mm = current->mm; 1612 1613 if ((get_region_id(ea) == VMALLOC_REGION_ID) || 1614 (get_region_id(ea) == IO_REGION_ID)) 1615 mm = &init_mm; 1616 1617 if (dsisr & DSISR_NOHPTE) 1618 flags |= HPTE_NOHPTE_UPDATE; 1619 1620 return hash_page_mm(mm, ea, access, trap, flags); 1621 } 1622 EXPORT_SYMBOL_GPL(hash_page); 1623 1624 DECLARE_INTERRUPT_HANDLER(__do_hash_fault); 1625 DEFINE_INTERRUPT_HANDLER(__do_hash_fault) 1626 { 1627 unsigned long ea = regs->dar; 1628 unsigned long dsisr = regs->dsisr; 1629 unsigned long access = _PAGE_PRESENT | _PAGE_READ; 1630 unsigned long flags = 0; 1631 struct mm_struct *mm; 1632 unsigned int region_id; 1633 long err; 1634 1635 if (unlikely(dsisr & (DSISR_BAD_FAULT_64S | DSISR_KEYFAULT))) { 1636 hash__do_page_fault(regs); 1637 return; 1638 } 1639 1640 region_id = get_region_id(ea); 1641 if ((region_id == VMALLOC_REGION_ID) || (region_id == IO_REGION_ID)) 1642 mm = &init_mm; 1643 else 1644 mm = current->mm; 1645 1646 if (dsisr & DSISR_NOHPTE) 1647 flags |= HPTE_NOHPTE_UPDATE; 1648 1649 if (dsisr & DSISR_ISSTORE) 1650 access |= _PAGE_WRITE; 1651 /* 1652 * We set _PAGE_PRIVILEGED only when 1653 * kernel mode access kernel space. 1654 * 1655 * _PAGE_PRIVILEGED is NOT set 1656 * 1) when kernel mode access user space 1657 * 2) user space access kernel space. 1658 */ 1659 access |= _PAGE_PRIVILEGED; 1660 if (user_mode(regs) || (region_id == USER_REGION_ID)) 1661 access &= ~_PAGE_PRIVILEGED; 1662 1663 if (TRAP(regs) == INTERRUPT_INST_STORAGE) 1664 access |= _PAGE_EXEC; 1665 1666 err = hash_page_mm(mm, ea, access, TRAP(regs), flags); 1667 if (unlikely(err < 0)) { 1668 // failed to instert a hash PTE due to an hypervisor error 1669 if (user_mode(regs)) { 1670 if (IS_ENABLED(CONFIG_PPC_SUBPAGE_PROT) && err == -2) 1671 _exception(SIGSEGV, regs, SEGV_ACCERR, ea); 1672 else 1673 _exception(SIGBUS, regs, BUS_ADRERR, ea); 1674 } else { 1675 bad_page_fault(regs, SIGBUS); 1676 } 1677 err = 0; 1678 1679 } else if (err) { 1680 hash__do_page_fault(regs); 1681 } 1682 } 1683 1684 /* 1685 * The _RAW interrupt entry checks for the in_nmi() case before 1686 * running the full handler. 1687 */ 1688 DEFINE_INTERRUPT_HANDLER_RAW(do_hash_fault) 1689 { 1690 /* 1691 * If we are in an "NMI" (e.g., an interrupt when soft-disabled), then 1692 * don't call hash_page, just fail the fault. This is required to 1693 * prevent re-entrancy problems in the hash code, namely perf 1694 * interrupts hitting while something holds H_PAGE_BUSY, and taking a 1695 * hash fault. See the comment in hash_preload(). 1696 * 1697 * We come here as a result of a DSI at a point where we don't want 1698 * to call hash_page, such as when we are accessing memory (possibly 1699 * user memory) inside a PMU interrupt that occurred while interrupts 1700 * were soft-disabled. We want to invoke the exception handler for 1701 * the access, or panic if there isn't a handler. 1702 */ 1703 if (unlikely(in_nmi())) { 1704 do_bad_page_fault_segv(regs); 1705 return 0; 1706 } 1707 1708 __do_hash_fault(regs); 1709 1710 return 0; 1711 } 1712 1713 #ifdef CONFIG_PPC_MM_SLICES 1714 static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) 1715 { 1716 int psize = get_slice_psize(mm, ea); 1717 1718 /* We only prefault standard pages for now */ 1719 if (unlikely(psize != mm_ctx_user_psize(&mm->context))) 1720 return false; 1721 1722 /* 1723 * Don't prefault if subpage protection is enabled for the EA. 1724 */ 1725 if (unlikely((psize == MMU_PAGE_4K) && subpage_protection(mm, ea))) 1726 return false; 1727 1728 return true; 1729 } 1730 #else 1731 static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) 1732 { 1733 return true; 1734 } 1735 #endif 1736 1737 static void hash_preload(struct mm_struct *mm, pte_t *ptep, unsigned long ea, 1738 bool is_exec, unsigned long trap) 1739 { 1740 unsigned long vsid; 1741 pgd_t *pgdir; 1742 int rc, ssize, update_flags = 0; 1743 unsigned long access = _PAGE_PRESENT | _PAGE_READ | (is_exec ? _PAGE_EXEC : 0); 1744 unsigned long flags; 1745 1746 BUG_ON(get_region_id(ea) != USER_REGION_ID); 1747 1748 if (!should_hash_preload(mm, ea)) 1749 return; 1750 1751 DBG_LOW("hash_preload(mm=%p, mm->pgdir=%p, ea=%016lx, access=%lx," 1752 " trap=%lx\n", mm, mm->pgd, ea, access, trap); 1753 1754 /* Get Linux PTE if available */ 1755 pgdir = mm->pgd; 1756 if (pgdir == NULL) 1757 return; 1758 1759 /* Get VSID */ 1760 ssize = user_segment_size(ea); 1761 vsid = get_user_vsid(&mm->context, ea, ssize); 1762 if (!vsid) 1763 return; 1764 1765 #ifdef CONFIG_PPC_64K_PAGES 1766 /* If either H_PAGE_4K_PFN or cache inhibited is set (and we are on 1767 * a 64K kernel), then we don't preload, hash_page() will take 1768 * care of it once we actually try to access the page. 1769 * That way we don't have to duplicate all of the logic for segment 1770 * page size demotion here 1771 * Called with PTL held, hence can be sure the value won't change in 1772 * between. 1773 */ 1774 if ((pte_val(*ptep) & H_PAGE_4K_PFN) || pte_ci(*ptep)) 1775 return; 1776 #endif /* CONFIG_PPC_64K_PAGES */ 1777 1778 /* 1779 * __hash_page_* must run with interrupts off, as it sets the 1780 * H_PAGE_BUSY bit. It's possible for perf interrupts to hit at any 1781 * time and may take a hash fault reading the user stack, see 1782 * read_user_stack_slow() in the powerpc/perf code. 1783 * 1784 * If that takes a hash fault on the same page as we lock here, it 1785 * will bail out when seeing H_PAGE_BUSY set, and retry the access 1786 * leading to an infinite loop. 1787 * 1788 * Disabling interrupts here does not prevent perf interrupts, but it 1789 * will prevent them taking hash faults (see the NMI test in 1790 * do_hash_page), then read_user_stack's copy_from_user_nofault will 1791 * fail and perf will fall back to read_user_stack_slow(), which 1792 * walks the Linux page tables. 1793 * 1794 * Interrupts must also be off for the duration of the 1795 * mm_is_thread_local test and update, to prevent preempt running the 1796 * mm on another CPU (XXX: this may be racy vs kthread_use_mm). 1797 */ 1798 local_irq_save(flags); 1799 1800 /* Is that local to this CPU ? */ 1801 if (mm_is_thread_local(mm)) 1802 update_flags |= HPTE_LOCAL_UPDATE; 1803 1804 /* Hash it in */ 1805 #ifdef CONFIG_PPC_64K_PAGES 1806 if (mm_ctx_user_psize(&mm->context) == MMU_PAGE_64K) 1807 rc = __hash_page_64K(ea, access, vsid, ptep, trap, 1808 update_flags, ssize); 1809 else 1810 #endif /* CONFIG_PPC_64K_PAGES */ 1811 rc = __hash_page_4K(ea, access, vsid, ptep, trap, update_flags, 1812 ssize, subpage_protection(mm, ea)); 1813 1814 /* Dump some info in case of hash insertion failure, they should 1815 * never happen so it is really useful to know if/when they do 1816 */ 1817 if (rc == -1) 1818 hash_failure_debug(ea, access, vsid, trap, ssize, 1819 mm_ctx_user_psize(&mm->context), 1820 mm_ctx_user_psize(&mm->context), 1821 pte_val(*ptep)); 1822 1823 local_irq_restore(flags); 1824 } 1825 1826 /* 1827 * This is called at the end of handling a user page fault, when the 1828 * fault has been handled by updating a PTE in the linux page tables. 1829 * We use it to preload an HPTE into the hash table corresponding to 1830 * the updated linux PTE. 1831 * 1832 * This must always be called with the pte lock held. 1833 */ 1834 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 1835 pte_t *ptep) 1836 { 1837 /* 1838 * We don't need to worry about _PAGE_PRESENT here because we are 1839 * called with either mm->page_table_lock held or ptl lock held 1840 */ 1841 unsigned long trap; 1842 bool is_exec; 1843 1844 if (radix_enabled()) 1845 return; 1846 1847 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 1848 if (!pte_young(*ptep) || address >= TASK_SIZE) 1849 return; 1850 1851 /* 1852 * We try to figure out if we are coming from an instruction 1853 * access fault and pass that down to __hash_page so we avoid 1854 * double-faulting on execution of fresh text. We have to test 1855 * for regs NULL since init will get here first thing at boot. 1856 * 1857 * We also avoid filling the hash if not coming from a fault. 1858 */ 1859 1860 trap = current->thread.regs ? TRAP(current->thread.regs) : 0UL; 1861 switch (trap) { 1862 case 0x300: 1863 is_exec = false; 1864 break; 1865 case 0x400: 1866 is_exec = true; 1867 break; 1868 default: 1869 return; 1870 } 1871 1872 hash_preload(vma->vm_mm, ptep, address, is_exec, trap); 1873 } 1874 1875 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1876 static inline void tm_flush_hash_page(int local) 1877 { 1878 /* 1879 * Transactions are not aborted by tlbiel, only tlbie. Without, syncing a 1880 * page back to a block device w/PIO could pick up transactional data 1881 * (bad!) so we force an abort here. Before the sync the page will be 1882 * made read-only, which will flush_hash_page. BIG ISSUE here: if the 1883 * kernel uses a page from userspace without unmapping it first, it may 1884 * see the speculated version. 1885 */ 1886 if (local && cpu_has_feature(CPU_FTR_TM) && current->thread.regs && 1887 MSR_TM_ACTIVE(current->thread.regs->msr)) { 1888 tm_enable(); 1889 tm_abort(TM_CAUSE_TLBI); 1890 } 1891 } 1892 #else 1893 static inline void tm_flush_hash_page(int local) 1894 { 1895 } 1896 #endif 1897 1898 /* 1899 * Return the global hash slot, corresponding to the given PTE, which contains 1900 * the HPTE. 1901 */ 1902 unsigned long pte_get_hash_gslot(unsigned long vpn, unsigned long shift, 1903 int ssize, real_pte_t rpte, unsigned int subpg_index) 1904 { 1905 unsigned long hash, gslot, hidx; 1906 1907 hash = hpt_hash(vpn, shift, ssize); 1908 hidx = __rpte_to_hidx(rpte, subpg_index); 1909 if (hidx & _PTEIDX_SECONDARY) 1910 hash = ~hash; 1911 gslot = (hash & htab_hash_mask) * HPTES_PER_GROUP; 1912 gslot += hidx & _PTEIDX_GROUP_IX; 1913 return gslot; 1914 } 1915 1916 void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize, 1917 unsigned long flags) 1918 { 1919 unsigned long index, shift, gslot; 1920 int local = flags & HPTE_LOCAL_UPDATE; 1921 1922 DBG_LOW("flush_hash_page(vpn=%016lx)\n", vpn); 1923 pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) { 1924 gslot = pte_get_hash_gslot(vpn, shift, ssize, pte, index); 1925 DBG_LOW(" sub %ld: gslot=%lx\n", index, gslot); 1926 /* 1927 * We use same base page size and actual psize, because we don't 1928 * use these functions for hugepage 1929 */ 1930 mmu_hash_ops.hpte_invalidate(gslot, vpn, psize, psize, 1931 ssize, local); 1932 } pte_iterate_hashed_end(); 1933 1934 tm_flush_hash_page(local); 1935 } 1936 1937 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1938 void flush_hash_hugepage(unsigned long vsid, unsigned long addr, 1939 pmd_t *pmdp, unsigned int psize, int ssize, 1940 unsigned long flags) 1941 { 1942 int i, max_hpte_count, valid; 1943 unsigned long s_addr; 1944 unsigned char *hpte_slot_array; 1945 unsigned long hidx, shift, vpn, hash, slot; 1946 int local = flags & HPTE_LOCAL_UPDATE; 1947 1948 s_addr = addr & HPAGE_PMD_MASK; 1949 hpte_slot_array = get_hpte_slot_array(pmdp); 1950 /* 1951 * IF we try to do a HUGE PTE update after a withdraw is done. 1952 * we will find the below NULL. This happens when we do 1953 * split_huge_pmd 1954 */ 1955 if (!hpte_slot_array) 1956 return; 1957 1958 if (mmu_hash_ops.hugepage_invalidate) { 1959 mmu_hash_ops.hugepage_invalidate(vsid, s_addr, hpte_slot_array, 1960 psize, ssize, local); 1961 goto tm_abort; 1962 } 1963 /* 1964 * No bluk hpte removal support, invalidate each entry 1965 */ 1966 shift = mmu_psize_defs[psize].shift; 1967 max_hpte_count = HPAGE_PMD_SIZE >> shift; 1968 for (i = 0; i < max_hpte_count; i++) { 1969 /* 1970 * 8 bits per each hpte entries 1971 * 000| [ secondary group (one bit) | hidx (3 bits) | valid bit] 1972 */ 1973 valid = hpte_valid(hpte_slot_array, i); 1974 if (!valid) 1975 continue; 1976 hidx = hpte_hash_index(hpte_slot_array, i); 1977 1978 /* get the vpn */ 1979 addr = s_addr + (i * (1ul << shift)); 1980 vpn = hpt_vpn(addr, vsid, ssize); 1981 hash = hpt_hash(vpn, shift, ssize); 1982 if (hidx & _PTEIDX_SECONDARY) 1983 hash = ~hash; 1984 1985 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; 1986 slot += hidx & _PTEIDX_GROUP_IX; 1987 mmu_hash_ops.hpte_invalidate(slot, vpn, psize, 1988 MMU_PAGE_16M, ssize, local); 1989 } 1990 tm_abort: 1991 tm_flush_hash_page(local); 1992 } 1993 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1994 1995 void flush_hash_range(unsigned long number, int local) 1996 { 1997 if (mmu_hash_ops.flush_hash_range) 1998 mmu_hash_ops.flush_hash_range(number, local); 1999 else { 2000 int i; 2001 struct ppc64_tlb_batch *batch = 2002 this_cpu_ptr(&ppc64_tlb_batch); 2003 2004 for (i = 0; i < number; i++) 2005 flush_hash_page(batch->vpn[i], batch->pte[i], 2006 batch->psize, batch->ssize, local); 2007 } 2008 } 2009 2010 long hpte_insert_repeating(unsigned long hash, unsigned long vpn, 2011 unsigned long pa, unsigned long rflags, 2012 unsigned long vflags, int psize, int ssize) 2013 { 2014 unsigned long hpte_group; 2015 long slot; 2016 2017 repeat: 2018 hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP; 2019 2020 /* Insert into the hash table, primary slot */ 2021 slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, vflags, 2022 psize, psize, ssize); 2023 2024 /* Primary is full, try the secondary */ 2025 if (unlikely(slot == -1)) { 2026 hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP; 2027 slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, 2028 vflags | HPTE_V_SECONDARY, 2029 psize, psize, ssize); 2030 if (slot == -1) { 2031 if (mftb() & 0x1) 2032 hpte_group = (hash & htab_hash_mask) * 2033 HPTES_PER_GROUP; 2034 2035 mmu_hash_ops.hpte_remove(hpte_group); 2036 goto repeat; 2037 } 2038 } 2039 2040 return slot; 2041 } 2042 2043 #ifdef CONFIG_DEBUG_PAGEALLOC 2044 static void kernel_map_linear_page(unsigned long vaddr, unsigned long lmi) 2045 { 2046 unsigned long hash; 2047 unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize); 2048 unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize); 2049 unsigned long mode = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL), HPTE_USE_KERNEL_KEY); 2050 long ret; 2051 2052 hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize); 2053 2054 /* Don't create HPTE entries for bad address */ 2055 if (!vsid) 2056 return; 2057 2058 ret = hpte_insert_repeating(hash, vpn, __pa(vaddr), mode, 2059 HPTE_V_BOLTED, 2060 mmu_linear_psize, mmu_kernel_ssize); 2061 2062 BUG_ON (ret < 0); 2063 spin_lock(&linear_map_hash_lock); 2064 BUG_ON(linear_map_hash_slots[lmi] & 0x80); 2065 linear_map_hash_slots[lmi] = ret | 0x80; 2066 spin_unlock(&linear_map_hash_lock); 2067 } 2068 2069 static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi) 2070 { 2071 unsigned long hash, hidx, slot; 2072 unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize); 2073 unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize); 2074 2075 hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize); 2076 spin_lock(&linear_map_hash_lock); 2077 BUG_ON(!(linear_map_hash_slots[lmi] & 0x80)); 2078 hidx = linear_map_hash_slots[lmi] & 0x7f; 2079 linear_map_hash_slots[lmi] = 0; 2080 spin_unlock(&linear_map_hash_lock); 2081 if (hidx & _PTEIDX_SECONDARY) 2082 hash = ~hash; 2083 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; 2084 slot += hidx & _PTEIDX_GROUP_IX; 2085 mmu_hash_ops.hpte_invalidate(slot, vpn, mmu_linear_psize, 2086 mmu_linear_psize, 2087 mmu_kernel_ssize, 0); 2088 } 2089 2090 void hash__kernel_map_pages(struct page *page, int numpages, int enable) 2091 { 2092 unsigned long flags, vaddr, lmi; 2093 int i; 2094 2095 local_irq_save(flags); 2096 for (i = 0; i < numpages; i++, page++) { 2097 vaddr = (unsigned long)page_address(page); 2098 lmi = __pa(vaddr) >> PAGE_SHIFT; 2099 if (lmi >= linear_map_hash_count) 2100 continue; 2101 if (enable) 2102 kernel_map_linear_page(vaddr, lmi); 2103 else 2104 kernel_unmap_linear_page(vaddr, lmi); 2105 } 2106 local_irq_restore(flags); 2107 } 2108 #endif /* CONFIG_DEBUG_PAGEALLOC */ 2109 2110 void hash__setup_initial_memory_limit(phys_addr_t first_memblock_base, 2111 phys_addr_t first_memblock_size) 2112 { 2113 /* 2114 * We don't currently support the first MEMBLOCK not mapping 0 2115 * physical on those processors 2116 */ 2117 BUG_ON(first_memblock_base != 0); 2118 2119 /* 2120 * On virtualized systems the first entry is our RMA region aka VRMA, 2121 * non-virtualized 64-bit hash MMU systems don't have a limitation 2122 * on real mode access. 2123 * 2124 * For guests on platforms before POWER9, we clamp the it limit to 1G 2125 * to avoid some funky things such as RTAS bugs etc... 2126 * 2127 * On POWER9 we limit to 1TB in case the host erroneously told us that 2128 * the RMA was >1TB. Effective address bits 0:23 are treated as zero 2129 * (meaning the access is aliased to zero i.e. addr = addr % 1TB) 2130 * for virtual real mode addressing and so it doesn't make sense to 2131 * have an area larger than 1TB as it can't be addressed. 2132 */ 2133 if (!early_cpu_has_feature(CPU_FTR_HVMODE)) { 2134 ppc64_rma_size = first_memblock_size; 2135 if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) 2136 ppc64_rma_size = min_t(u64, ppc64_rma_size, 0x40000000); 2137 else 2138 ppc64_rma_size = min_t(u64, ppc64_rma_size, 2139 1UL << SID_SHIFT_1T); 2140 2141 /* Finally limit subsequent allocations */ 2142 memblock_set_current_limit(ppc64_rma_size); 2143 } else { 2144 ppc64_rma_size = ULONG_MAX; 2145 } 2146 } 2147 2148 #ifdef CONFIG_DEBUG_FS 2149 2150 static int hpt_order_get(void *data, u64 *val) 2151 { 2152 *val = ppc64_pft_size; 2153 return 0; 2154 } 2155 2156 static int hpt_order_set(void *data, u64 val) 2157 { 2158 int ret; 2159 2160 if (!mmu_hash_ops.resize_hpt) 2161 return -ENODEV; 2162 2163 cpus_read_lock(); 2164 ret = mmu_hash_ops.resize_hpt(val); 2165 cpus_read_unlock(); 2166 2167 return ret; 2168 } 2169 2170 DEFINE_DEBUGFS_ATTRIBUTE(fops_hpt_order, hpt_order_get, hpt_order_set, "%llu\n"); 2171 2172 static int __init hash64_debugfs(void) 2173 { 2174 debugfs_create_file("hpt_order", 0600, arch_debugfs_dir, NULL, 2175 &fops_hpt_order); 2176 return 0; 2177 } 2178 machine_device_initcall(pseries, hash64_debugfs); 2179 #endif /* CONFIG_DEBUG_FS */ 2180 2181 void __init print_system_hash_info(void) 2182 { 2183 pr_info("ppc64_pft_size = 0x%llx\n", ppc64_pft_size); 2184 2185 if (htab_hash_mask) 2186 pr_info("htab_hash_mask = 0x%lx\n", htab_hash_mask); 2187 } 2188