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 #include <linux/random.h> 41 #include <linux/elf-randomize.h> 42 #include <linux/of_fdt.h> 43 44 #include <asm/interrupt.h> 45 #include <asm/processor.h> 46 #include <asm/mmu.h> 47 #include <asm/mmu_context.h> 48 #include <asm/page.h> 49 #include <asm/types.h> 50 #include <linux/uaccess.h> 51 #include <asm/machdep.h> 52 #include <asm/io.h> 53 #include <asm/eeh.h> 54 #include <asm/tlb.h> 55 #include <asm/cacheflush.h> 56 #include <asm/cputable.h> 57 #include <asm/sections.h> 58 #include <asm/copro.h> 59 #include <asm/udbg.h> 60 #include <asm/code-patching.h> 61 #include <asm/fadump.h> 62 #include <asm/firmware.h> 63 #include <asm/tm.h> 64 #include <asm/trace.h> 65 #include <asm/ps3.h> 66 #include <asm/pte-walk.h> 67 #include <asm/asm-prototypes.h> 68 #include <asm/ultravisor.h> 69 70 #include <mm/mmu_decl.h> 71 72 #include "internal.h" 73 74 75 #ifdef DEBUG 76 #define DBG(fmt...) udbg_printf(fmt) 77 #else 78 #define DBG(fmt...) 79 #endif 80 81 #ifdef DEBUG_LOW 82 #define DBG_LOW(fmt...) udbg_printf(fmt) 83 #else 84 #define DBG_LOW(fmt...) 85 #endif 86 87 #define KB (1024) 88 #define MB (1024*KB) 89 #define GB (1024L*MB) 90 91 /* 92 * Note: pte --> Linux PTE 93 * HPTE --> PowerPC Hashed Page Table Entry 94 * 95 * Execution context: 96 * htab_initialize is called with the MMU off (of course), but 97 * the kernel has been copied down to zero so it can directly 98 * reference global data. At this point it is very difficult 99 * to print debug info. 100 * 101 */ 102 103 static unsigned long _SDR1; 104 105 u8 hpte_page_sizes[1 << LP_BITS]; 106 EXPORT_SYMBOL_GPL(hpte_page_sizes); 107 108 struct hash_pte *htab_address; 109 unsigned long htab_size_bytes; 110 unsigned long htab_hash_mask; 111 EXPORT_SYMBOL_GPL(htab_hash_mask); 112 int mmu_linear_psize = MMU_PAGE_4K; 113 EXPORT_SYMBOL_GPL(mmu_linear_psize); 114 int mmu_virtual_psize = MMU_PAGE_4K; 115 int mmu_vmalloc_psize = MMU_PAGE_4K; 116 EXPORT_SYMBOL_GPL(mmu_vmalloc_psize); 117 int mmu_io_psize = MMU_PAGE_4K; 118 int mmu_kernel_ssize = MMU_SEGSIZE_256M; 119 EXPORT_SYMBOL_GPL(mmu_kernel_ssize); 120 int mmu_highuser_ssize = MMU_SEGSIZE_256M; 121 u16 mmu_slb_size = 64; 122 EXPORT_SYMBOL_GPL(mmu_slb_size); 123 #ifdef CONFIG_PPC_64K_PAGES 124 int mmu_ci_restrictions; 125 #endif 126 #ifdef CONFIG_DEBUG_PAGEALLOC 127 static u8 *linear_map_hash_slots; 128 static unsigned long linear_map_hash_count; 129 static DEFINE_SPINLOCK(linear_map_hash_lock); 130 #endif /* CONFIG_DEBUG_PAGEALLOC */ 131 struct mmu_hash_ops mmu_hash_ops; 132 EXPORT_SYMBOL(mmu_hash_ops); 133 134 /* 135 * These are definitions of page sizes arrays to be used when none 136 * is provided by the firmware. 137 */ 138 139 /* 140 * Fallback (4k pages only) 141 */ 142 static struct mmu_psize_def mmu_psize_defaults[] = { 143 [MMU_PAGE_4K] = { 144 .shift = 12, 145 .sllp = 0, 146 .penc = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1}, 147 .avpnm = 0, 148 .tlbiel = 0, 149 }, 150 }; 151 152 /* 153 * POWER4, GPUL, POWER5 154 * 155 * Support for 16Mb large pages 156 */ 157 static struct mmu_psize_def mmu_psize_defaults_gp[] = { 158 [MMU_PAGE_4K] = { 159 .shift = 12, 160 .sllp = 0, 161 .penc = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1}, 162 .avpnm = 0, 163 .tlbiel = 1, 164 }, 165 [MMU_PAGE_16M] = { 166 .shift = 24, 167 .sllp = SLB_VSID_L, 168 .penc = {[0 ... MMU_PAGE_16M - 1] = -1, [MMU_PAGE_16M] = 0, 169 [MMU_PAGE_16M + 1 ... MMU_PAGE_COUNT - 1] = -1 }, 170 .avpnm = 0x1UL, 171 .tlbiel = 0, 172 }, 173 }; 174 175 static inline void tlbiel_hash_set_isa206(unsigned int set, unsigned int is) 176 { 177 unsigned long rb; 178 179 rb = (set << PPC_BITLSHIFT(51)) | (is << PPC_BITLSHIFT(53)); 180 181 asm volatile("tlbiel %0" : : "r" (rb)); 182 } 183 184 /* 185 * tlbiel instruction for hash, set invalidation 186 * i.e., r=1 and is=01 or is=10 or is=11 187 */ 188 static __always_inline void tlbiel_hash_set_isa300(unsigned int set, unsigned int is, 189 unsigned int pid, 190 unsigned int ric, unsigned int prs) 191 { 192 unsigned long rb; 193 unsigned long rs; 194 unsigned int r = 0; /* hash format */ 195 196 rb = (set << PPC_BITLSHIFT(51)) | (is << PPC_BITLSHIFT(53)); 197 rs = ((unsigned long)pid << PPC_BITLSHIFT(31)); 198 199 asm volatile(PPC_TLBIEL(%0, %1, %2, %3, %4) 200 : : "r"(rb), "r"(rs), "i"(ric), "i"(prs), "i"(r) 201 : "memory"); 202 } 203 204 205 static void tlbiel_all_isa206(unsigned int num_sets, unsigned int is) 206 { 207 unsigned int set; 208 209 asm volatile("ptesync": : :"memory"); 210 211 for (set = 0; set < num_sets; set++) 212 tlbiel_hash_set_isa206(set, is); 213 214 ppc_after_tlbiel_barrier(); 215 } 216 217 static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is) 218 { 219 unsigned int set; 220 221 asm volatile("ptesync": : :"memory"); 222 223 /* 224 * Flush the partition table cache if this is HV mode. 225 */ 226 if (early_cpu_has_feature(CPU_FTR_HVMODE)) 227 tlbiel_hash_set_isa300(0, is, 0, 2, 0); 228 229 /* 230 * Now invalidate the process table cache. UPRT=0 HPT modes (what 231 * current hardware implements) do not use the process table, but 232 * add the flushes anyway. 233 * 234 * From ISA v3.0B p. 1078: 235 * The following forms are invalid. 236 * * PRS=1, R=0, and RIC!=2 (The only process-scoped 237 * HPT caching is of the Process Table.) 238 */ 239 tlbiel_hash_set_isa300(0, is, 0, 2, 1); 240 241 /* 242 * Then flush the sets of the TLB proper. Hash mode uses 243 * partition scoped TLB translations, which may be flushed 244 * in !HV mode. 245 */ 246 for (set = 0; set < num_sets; set++) 247 tlbiel_hash_set_isa300(set, is, 0, 0, 0); 248 249 ppc_after_tlbiel_barrier(); 250 251 asm volatile(PPC_ISA_3_0_INVALIDATE_ERAT "; isync" : : :"memory"); 252 } 253 254 void hash__tlbiel_all(unsigned int action) 255 { 256 unsigned int is; 257 258 switch (action) { 259 case TLB_INVAL_SCOPE_GLOBAL: 260 is = 3; 261 break; 262 case TLB_INVAL_SCOPE_LPID: 263 is = 2; 264 break; 265 default: 266 BUG(); 267 } 268 269 if (early_cpu_has_feature(CPU_FTR_ARCH_300)) 270 tlbiel_all_isa300(POWER9_TLB_SETS_HASH, is); 271 else if (early_cpu_has_feature(CPU_FTR_ARCH_207S)) 272 tlbiel_all_isa206(POWER8_TLB_SETS, is); 273 else if (early_cpu_has_feature(CPU_FTR_ARCH_206)) 274 tlbiel_all_isa206(POWER7_TLB_SETS, is); 275 else 276 WARN(1, "%s called on pre-POWER7 CPU\n", __func__); 277 } 278 279 /* 280 * 'R' and 'C' update notes: 281 * - Under pHyp or KVM, the updatepp path will not set C, thus it *will* 282 * create writeable HPTEs without C set, because the hcall H_PROTECT 283 * that we use in that case will not update C 284 * - The above is however not a problem, because we also don't do that 285 * fancy "no flush" variant of eviction and we use H_REMOVE which will 286 * do the right thing and thus we don't have the race I described earlier 287 * 288 * - Under bare metal, we do have the race, so we need R and C set 289 * - We make sure R is always set and never lost 290 * - C is _PAGE_DIRTY, and *should* always be set for a writeable mapping 291 */ 292 unsigned long htab_convert_pte_flags(unsigned long pteflags, unsigned long flags) 293 { 294 unsigned long rflags = 0; 295 296 /* _PAGE_EXEC -> NOEXEC */ 297 if ((pteflags & _PAGE_EXEC) == 0) 298 rflags |= HPTE_R_N; 299 /* 300 * PPP bits: 301 * Linux uses slb key 0 for kernel and 1 for user. 302 * kernel RW areas are mapped with PPP=0b000 303 * User area is mapped with PPP=0b010 for read/write 304 * or PPP=0b011 for read-only (including writeable but clean pages). 305 */ 306 if (pteflags & _PAGE_PRIVILEGED) { 307 /* 308 * Kernel read only mapped with ppp bits 0b110 309 */ 310 if (!(pteflags & _PAGE_WRITE)) { 311 if (mmu_has_feature(MMU_FTR_KERNEL_RO)) 312 rflags |= (HPTE_R_PP0 | 0x2); 313 else 314 rflags |= 0x3; 315 } 316 } else { 317 if (pteflags & _PAGE_RWX) 318 rflags |= 0x2; 319 if (!((pteflags & _PAGE_WRITE) && (pteflags & _PAGE_DIRTY))) 320 rflags |= 0x1; 321 } 322 /* 323 * We can't allow hardware to update hpte bits. Hence always 324 * set 'R' bit and set 'C' if it is a write fault 325 */ 326 rflags |= HPTE_R_R; 327 328 if (pteflags & _PAGE_DIRTY) 329 rflags |= HPTE_R_C; 330 /* 331 * Add in WIG bits 332 */ 333 334 if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_TOLERANT) 335 rflags |= HPTE_R_I; 336 else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_NON_IDEMPOTENT) 337 rflags |= (HPTE_R_I | HPTE_R_G); 338 else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_SAO) 339 rflags |= (HPTE_R_W | HPTE_R_I | HPTE_R_M); 340 else 341 /* 342 * Add memory coherence if cache inhibited is not set 343 */ 344 rflags |= HPTE_R_M; 345 346 rflags |= pte_to_hpte_pkey_bits(pteflags, flags); 347 return rflags; 348 } 349 350 int htab_bolt_mapping(unsigned long vstart, unsigned long vend, 351 unsigned long pstart, unsigned long prot, 352 int psize, int ssize) 353 { 354 unsigned long vaddr, paddr; 355 unsigned int step, shift; 356 int ret = 0; 357 358 shift = mmu_psize_defs[psize].shift; 359 step = 1 << shift; 360 361 prot = htab_convert_pte_flags(prot, HPTE_USE_KERNEL_KEY); 362 363 DBG("htab_bolt_mapping(%lx..%lx -> %lx (%lx,%d,%d)\n", 364 vstart, vend, pstart, prot, psize, ssize); 365 366 /* Carefully map only the possible range */ 367 vaddr = ALIGN(vstart, step); 368 paddr = ALIGN(pstart, step); 369 vend = ALIGN_DOWN(vend, step); 370 371 for (; vaddr < vend; vaddr += step, paddr += step) { 372 unsigned long hash, hpteg; 373 unsigned long vsid = get_kernel_vsid(vaddr, ssize); 374 unsigned long vpn = hpt_vpn(vaddr, vsid, ssize); 375 unsigned long tprot = prot; 376 bool secondary_hash = false; 377 378 /* 379 * If we hit a bad address return error. 380 */ 381 if (!vsid) 382 return -1; 383 /* Make kernel text executable */ 384 if (overlaps_kernel_text(vaddr, vaddr + step)) 385 tprot &= ~HPTE_R_N; 386 387 /* 388 * If relocatable, check if it overlaps interrupt vectors that 389 * are copied down to real 0. For relocatable kernel 390 * (e.g. kdump case) we copy interrupt vectors down to real 391 * address 0. Mark that region as executable. This is 392 * because on p8 system with relocation on exception feature 393 * enabled, exceptions are raised with MMU (IR=DR=1) ON. Hence 394 * in order to execute the interrupt handlers in virtual 395 * mode the vector region need to be marked as executable. 396 */ 397 if ((PHYSICAL_START > MEMORY_START) && 398 overlaps_interrupt_vector_text(vaddr, vaddr + step)) 399 tprot &= ~HPTE_R_N; 400 401 hash = hpt_hash(vpn, shift, ssize); 402 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 403 404 BUG_ON(!mmu_hash_ops.hpte_insert); 405 repeat: 406 ret = mmu_hash_ops.hpte_insert(hpteg, vpn, paddr, tprot, 407 HPTE_V_BOLTED, psize, psize, 408 ssize); 409 if (ret == -1) { 410 /* 411 * Try to to keep bolted entries in primary. 412 * Remove non bolted entries and try insert again 413 */ 414 ret = mmu_hash_ops.hpte_remove(hpteg); 415 if (ret != -1) 416 ret = mmu_hash_ops.hpte_insert(hpteg, vpn, paddr, tprot, 417 HPTE_V_BOLTED, psize, psize, 418 ssize); 419 if (ret == -1 && !secondary_hash) { 420 secondary_hash = true; 421 hpteg = ((~hash & htab_hash_mask) * HPTES_PER_GROUP); 422 goto repeat; 423 } 424 } 425 426 if (ret < 0) 427 break; 428 429 cond_resched(); 430 #ifdef CONFIG_DEBUG_PAGEALLOC 431 if (debug_pagealloc_enabled() && 432 (paddr >> PAGE_SHIFT) < linear_map_hash_count) 433 linear_map_hash_slots[paddr >> PAGE_SHIFT] = ret | 0x80; 434 #endif /* CONFIG_DEBUG_PAGEALLOC */ 435 } 436 return ret < 0 ? ret : 0; 437 } 438 439 int htab_remove_mapping(unsigned long vstart, unsigned long vend, 440 int psize, int ssize) 441 { 442 unsigned long vaddr, time_limit; 443 unsigned int step, shift; 444 int rc; 445 int ret = 0; 446 447 shift = mmu_psize_defs[psize].shift; 448 step = 1 << shift; 449 450 if (!mmu_hash_ops.hpte_removebolted) 451 return -ENODEV; 452 453 /* Unmap the full range specificied */ 454 vaddr = ALIGN_DOWN(vstart, step); 455 time_limit = jiffies + HZ; 456 457 for (;vaddr < vend; vaddr += step) { 458 rc = mmu_hash_ops.hpte_removebolted(vaddr, psize, ssize); 459 460 /* 461 * For large number of mappings introduce a cond_resched() 462 * to prevent softlockup warnings. 463 */ 464 if (time_after(jiffies, time_limit)) { 465 cond_resched(); 466 time_limit = jiffies + HZ; 467 } 468 if (rc == -ENOENT) { 469 ret = -ENOENT; 470 continue; 471 } 472 if (rc < 0) 473 return rc; 474 } 475 476 return ret; 477 } 478 479 static bool disable_1tb_segments = false; 480 481 static int __init parse_disable_1tb_segments(char *p) 482 { 483 disable_1tb_segments = true; 484 return 0; 485 } 486 early_param("disable_1tb_segments", parse_disable_1tb_segments); 487 488 static int __init htab_dt_scan_seg_sizes(unsigned long node, 489 const char *uname, int depth, 490 void *data) 491 { 492 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 493 const __be32 *prop; 494 int size = 0; 495 496 /* We are scanning "cpu" nodes only */ 497 if (type == NULL || strcmp(type, "cpu") != 0) 498 return 0; 499 500 prop = of_get_flat_dt_prop(node, "ibm,processor-segment-sizes", &size); 501 if (prop == NULL) 502 return 0; 503 for (; size >= 4; size -= 4, ++prop) { 504 if (be32_to_cpu(prop[0]) == 40) { 505 DBG("1T segment support detected\n"); 506 507 if (disable_1tb_segments) { 508 DBG("1T segments disabled by command line\n"); 509 break; 510 } 511 512 cur_cpu_spec->mmu_features |= MMU_FTR_1T_SEGMENT; 513 return 1; 514 } 515 } 516 cur_cpu_spec->mmu_features &= ~MMU_FTR_NO_SLBIE_B; 517 return 0; 518 } 519 520 static int __init get_idx_from_shift(unsigned int shift) 521 { 522 int idx = -1; 523 524 switch (shift) { 525 case 0xc: 526 idx = MMU_PAGE_4K; 527 break; 528 case 0x10: 529 idx = MMU_PAGE_64K; 530 break; 531 case 0x14: 532 idx = MMU_PAGE_1M; 533 break; 534 case 0x18: 535 idx = MMU_PAGE_16M; 536 break; 537 case 0x22: 538 idx = MMU_PAGE_16G; 539 break; 540 } 541 return idx; 542 } 543 544 static int __init htab_dt_scan_page_sizes(unsigned long node, 545 const char *uname, int depth, 546 void *data) 547 { 548 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 549 const __be32 *prop; 550 int size = 0; 551 552 /* We are scanning "cpu" nodes only */ 553 if (type == NULL || strcmp(type, "cpu") != 0) 554 return 0; 555 556 prop = of_get_flat_dt_prop(node, "ibm,segment-page-sizes", &size); 557 if (!prop) 558 return 0; 559 560 pr_info("Page sizes from device-tree:\n"); 561 size /= 4; 562 cur_cpu_spec->mmu_features &= ~(MMU_FTR_16M_PAGE); 563 while(size > 0) { 564 unsigned int base_shift = be32_to_cpu(prop[0]); 565 unsigned int slbenc = be32_to_cpu(prop[1]); 566 unsigned int lpnum = be32_to_cpu(prop[2]); 567 struct mmu_psize_def *def; 568 int idx, base_idx; 569 570 size -= 3; prop += 3; 571 base_idx = get_idx_from_shift(base_shift); 572 if (base_idx < 0) { 573 /* skip the pte encoding also */ 574 prop += lpnum * 2; size -= lpnum * 2; 575 continue; 576 } 577 def = &mmu_psize_defs[base_idx]; 578 if (base_idx == MMU_PAGE_16M) 579 cur_cpu_spec->mmu_features |= MMU_FTR_16M_PAGE; 580 581 def->shift = base_shift; 582 if (base_shift <= 23) 583 def->avpnm = 0; 584 else 585 def->avpnm = (1 << (base_shift - 23)) - 1; 586 def->sllp = slbenc; 587 /* 588 * We don't know for sure what's up with tlbiel, so 589 * for now we only set it for 4K and 64K pages 590 */ 591 if (base_idx == MMU_PAGE_4K || base_idx == MMU_PAGE_64K) 592 def->tlbiel = 1; 593 else 594 def->tlbiel = 0; 595 596 while (size > 0 && lpnum) { 597 unsigned int shift = be32_to_cpu(prop[0]); 598 int penc = be32_to_cpu(prop[1]); 599 600 prop += 2; size -= 2; 601 lpnum--; 602 603 idx = get_idx_from_shift(shift); 604 if (idx < 0) 605 continue; 606 607 if (penc == -1) 608 pr_err("Invalid penc for base_shift=%d " 609 "shift=%d\n", base_shift, shift); 610 611 def->penc[idx] = penc; 612 pr_info("base_shift=%d: shift=%d, sllp=0x%04lx," 613 " avpnm=0x%08lx, tlbiel=%d, penc=%d\n", 614 base_shift, shift, def->sllp, 615 def->avpnm, def->tlbiel, def->penc[idx]); 616 } 617 } 618 619 return 1; 620 } 621 622 #ifdef CONFIG_HUGETLB_PAGE 623 /* 624 * Scan for 16G memory blocks that have been set aside for huge pages 625 * and reserve those blocks for 16G huge pages. 626 */ 627 static int __init htab_dt_scan_hugepage_blocks(unsigned long node, 628 const char *uname, int depth, 629 void *data) { 630 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 631 const __be64 *addr_prop; 632 const __be32 *page_count_prop; 633 unsigned int expected_pages; 634 long unsigned int phys_addr; 635 long unsigned int block_size; 636 637 /* We are scanning "memory" nodes only */ 638 if (type == NULL || strcmp(type, "memory") != 0) 639 return 0; 640 641 /* 642 * This property is the log base 2 of the number of virtual pages that 643 * will represent this memory block. 644 */ 645 page_count_prop = of_get_flat_dt_prop(node, "ibm,expected#pages", NULL); 646 if (page_count_prop == NULL) 647 return 0; 648 expected_pages = (1 << be32_to_cpu(page_count_prop[0])); 649 addr_prop = of_get_flat_dt_prop(node, "reg", NULL); 650 if (addr_prop == NULL) 651 return 0; 652 phys_addr = be64_to_cpu(addr_prop[0]); 653 block_size = be64_to_cpu(addr_prop[1]); 654 if (block_size != (16 * GB)) 655 return 0; 656 printk(KERN_INFO "Huge page(16GB) memory: " 657 "addr = 0x%lX size = 0x%lX pages = %d\n", 658 phys_addr, block_size, expected_pages); 659 if (phys_addr + block_size * expected_pages <= memblock_end_of_DRAM()) { 660 memblock_reserve(phys_addr, block_size * expected_pages); 661 pseries_add_gpage(phys_addr, block_size, expected_pages); 662 } 663 return 0; 664 } 665 #endif /* CONFIG_HUGETLB_PAGE */ 666 667 static void __init mmu_psize_set_default_penc(void) 668 { 669 int bpsize, apsize; 670 for (bpsize = 0; bpsize < MMU_PAGE_COUNT; bpsize++) 671 for (apsize = 0; apsize < MMU_PAGE_COUNT; apsize++) 672 mmu_psize_defs[bpsize].penc[apsize] = -1; 673 } 674 675 #ifdef CONFIG_PPC_64K_PAGES 676 677 static bool __init might_have_hea(void) 678 { 679 /* 680 * The HEA ethernet adapter requires awareness of the 681 * GX bus. Without that awareness we can easily assume 682 * we will never see an HEA ethernet device. 683 */ 684 #ifdef CONFIG_IBMEBUS 685 return !cpu_has_feature(CPU_FTR_ARCH_207S) && 686 firmware_has_feature(FW_FEATURE_SPLPAR); 687 #else 688 return false; 689 #endif 690 } 691 692 #endif /* #ifdef CONFIG_PPC_64K_PAGES */ 693 694 static void __init htab_scan_page_sizes(void) 695 { 696 int rc; 697 698 /* se the invalid penc to -1 */ 699 mmu_psize_set_default_penc(); 700 701 /* Default to 4K pages only */ 702 memcpy(mmu_psize_defs, mmu_psize_defaults, 703 sizeof(mmu_psize_defaults)); 704 705 /* 706 * Try to find the available page sizes in the device-tree 707 */ 708 rc = of_scan_flat_dt(htab_dt_scan_page_sizes, NULL); 709 if (rc == 0 && early_mmu_has_feature(MMU_FTR_16M_PAGE)) { 710 /* 711 * Nothing in the device-tree, but the CPU supports 16M pages, 712 * so let's fallback on a known size list for 16M capable CPUs. 713 */ 714 memcpy(mmu_psize_defs, mmu_psize_defaults_gp, 715 sizeof(mmu_psize_defaults_gp)); 716 } 717 718 #ifdef CONFIG_HUGETLB_PAGE 719 if (!hugetlb_disabled && !early_radix_enabled() ) { 720 /* Reserve 16G huge page memory sections for huge pages */ 721 of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL); 722 } 723 #endif /* CONFIG_HUGETLB_PAGE */ 724 } 725 726 /* 727 * Fill in the hpte_page_sizes[] array. 728 * We go through the mmu_psize_defs[] array looking for all the 729 * supported base/actual page size combinations. Each combination 730 * has a unique pagesize encoding (penc) value in the low bits of 731 * the LP field of the HPTE. For actual page sizes less than 1MB, 732 * some of the upper LP bits are used for RPN bits, meaning that 733 * we need to fill in several entries in hpte_page_sizes[]. 734 * 735 * In diagrammatic form, with r = RPN bits and z = page size bits: 736 * PTE LP actual page size 737 * rrrr rrrz >=8KB 738 * rrrr rrzz >=16KB 739 * rrrr rzzz >=32KB 740 * rrrr zzzz >=64KB 741 * ... 742 * 743 * The zzzz bits are implementation-specific but are chosen so that 744 * no encoding for a larger page size uses the same value in its 745 * low-order N bits as the encoding for the 2^(12+N) byte page size 746 * (if it exists). 747 */ 748 static void __init init_hpte_page_sizes(void) 749 { 750 long int ap, bp; 751 long int shift, penc; 752 753 for (bp = 0; bp < MMU_PAGE_COUNT; ++bp) { 754 if (!mmu_psize_defs[bp].shift) 755 continue; /* not a supported page size */ 756 for (ap = bp; ap < MMU_PAGE_COUNT; ++ap) { 757 penc = mmu_psize_defs[bp].penc[ap]; 758 if (penc == -1 || !mmu_psize_defs[ap].shift) 759 continue; 760 shift = mmu_psize_defs[ap].shift - LP_SHIFT; 761 if (shift <= 0) 762 continue; /* should never happen */ 763 /* 764 * For page sizes less than 1MB, this loop 765 * replicates the entry for all possible values 766 * of the rrrr bits. 767 */ 768 while (penc < (1 << LP_BITS)) { 769 hpte_page_sizes[penc] = (ap << 4) | bp; 770 penc += 1 << shift; 771 } 772 } 773 } 774 } 775 776 static void __init htab_init_page_sizes(void) 777 { 778 bool aligned = true; 779 init_hpte_page_sizes(); 780 781 if (!debug_pagealloc_enabled()) { 782 /* 783 * Pick a size for the linear mapping. Currently, we only 784 * support 16M, 1M and 4K which is the default 785 */ 786 if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && 787 (unsigned long)_stext % 0x1000000) { 788 if (mmu_psize_defs[MMU_PAGE_16M].shift) 789 pr_warn("Kernel not 16M aligned, disabling 16M linear map alignment\n"); 790 aligned = false; 791 } 792 793 if (mmu_psize_defs[MMU_PAGE_16M].shift && aligned) 794 mmu_linear_psize = MMU_PAGE_16M; 795 else if (mmu_psize_defs[MMU_PAGE_1M].shift) 796 mmu_linear_psize = MMU_PAGE_1M; 797 } 798 799 #ifdef CONFIG_PPC_64K_PAGES 800 /* 801 * Pick a size for the ordinary pages. Default is 4K, we support 802 * 64K for user mappings and vmalloc if supported by the processor. 803 * We only use 64k for ioremap if the processor 804 * (and firmware) support cache-inhibited large pages. 805 * If not, we use 4k and set mmu_ci_restrictions so that 806 * hash_page knows to switch processes that use cache-inhibited 807 * mappings to 4k pages. 808 */ 809 if (mmu_psize_defs[MMU_PAGE_64K].shift) { 810 mmu_virtual_psize = MMU_PAGE_64K; 811 mmu_vmalloc_psize = MMU_PAGE_64K; 812 if (mmu_linear_psize == MMU_PAGE_4K) 813 mmu_linear_psize = MMU_PAGE_64K; 814 if (mmu_has_feature(MMU_FTR_CI_LARGE_PAGE)) { 815 /* 816 * When running on pSeries using 64k pages for ioremap 817 * would stop us accessing the HEA ethernet. So if we 818 * have the chance of ever seeing one, stay at 4k. 819 */ 820 if (!might_have_hea()) 821 mmu_io_psize = MMU_PAGE_64K; 822 } else 823 mmu_ci_restrictions = 1; 824 } 825 #endif /* CONFIG_PPC_64K_PAGES */ 826 827 #ifdef CONFIG_SPARSEMEM_VMEMMAP 828 /* 829 * We try to use 16M pages for vmemmap if that is supported 830 * and we have at least 1G of RAM at boot 831 */ 832 if (mmu_psize_defs[MMU_PAGE_16M].shift && 833 memblock_phys_mem_size() >= 0x40000000) 834 mmu_vmemmap_psize = MMU_PAGE_16M; 835 else 836 mmu_vmemmap_psize = mmu_virtual_psize; 837 #endif /* CONFIG_SPARSEMEM_VMEMMAP */ 838 839 printk(KERN_DEBUG "Page orders: linear mapping = %d, " 840 "virtual = %d, io = %d" 841 #ifdef CONFIG_SPARSEMEM_VMEMMAP 842 ", vmemmap = %d" 843 #endif 844 "\n", 845 mmu_psize_defs[mmu_linear_psize].shift, 846 mmu_psize_defs[mmu_virtual_psize].shift, 847 mmu_psize_defs[mmu_io_psize].shift 848 #ifdef CONFIG_SPARSEMEM_VMEMMAP 849 ,mmu_psize_defs[mmu_vmemmap_psize].shift 850 #endif 851 ); 852 } 853 854 static int __init htab_dt_scan_pftsize(unsigned long node, 855 const char *uname, int depth, 856 void *data) 857 { 858 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 859 const __be32 *prop; 860 861 /* We are scanning "cpu" nodes only */ 862 if (type == NULL || strcmp(type, "cpu") != 0) 863 return 0; 864 865 prop = of_get_flat_dt_prop(node, "ibm,pft-size", NULL); 866 if (prop != NULL) { 867 /* pft_size[0] is the NUMA CEC cookie */ 868 ppc64_pft_size = be32_to_cpu(prop[1]); 869 return 1; 870 } 871 return 0; 872 } 873 874 unsigned htab_shift_for_mem_size(unsigned long mem_size) 875 { 876 unsigned memshift = __ilog2(mem_size); 877 unsigned pshift = mmu_psize_defs[mmu_virtual_psize].shift; 878 unsigned pteg_shift; 879 880 /* round mem_size up to next power of 2 */ 881 if ((1UL << memshift) < mem_size) 882 memshift += 1; 883 884 /* aim for 2 pages / pteg */ 885 pteg_shift = memshift - (pshift + 1); 886 887 /* 888 * 2^11 PTEGS of 128 bytes each, ie. 2^18 bytes is the minimum htab 889 * size permitted by the architecture. 890 */ 891 return max(pteg_shift + 7, 18U); 892 } 893 894 static unsigned long __init htab_get_table_size(void) 895 { 896 /* 897 * If hash size isn't already provided by the platform, we try to 898 * retrieve it from the device-tree. If it's not there neither, we 899 * calculate it now based on the total RAM size 900 */ 901 if (ppc64_pft_size == 0) 902 of_scan_flat_dt(htab_dt_scan_pftsize, NULL); 903 if (ppc64_pft_size) 904 return 1UL << ppc64_pft_size; 905 906 return 1UL << htab_shift_for_mem_size(memblock_phys_mem_size()); 907 } 908 909 #ifdef CONFIG_MEMORY_HOTPLUG 910 static int resize_hpt_for_hotplug(unsigned long new_mem_size) 911 { 912 unsigned target_hpt_shift; 913 914 if (!mmu_hash_ops.resize_hpt) 915 return 0; 916 917 target_hpt_shift = htab_shift_for_mem_size(new_mem_size); 918 919 /* 920 * To avoid lots of HPT resizes if memory size is fluctuating 921 * across a boundary, we deliberately have some hysterisis 922 * here: we immediately increase the HPT size if the target 923 * shift exceeds the current shift, but we won't attempt to 924 * reduce unless the target shift is at least 2 below the 925 * current shift 926 */ 927 if (target_hpt_shift > ppc64_pft_size || 928 target_hpt_shift < ppc64_pft_size - 1) 929 return mmu_hash_ops.resize_hpt(target_hpt_shift); 930 931 return 0; 932 } 933 934 int hash__create_section_mapping(unsigned long start, unsigned long end, 935 int nid, pgprot_t prot) 936 { 937 int rc; 938 939 if (end >= H_VMALLOC_START) { 940 pr_warn("Outside the supported range\n"); 941 return -1; 942 } 943 944 resize_hpt_for_hotplug(memblock_phys_mem_size()); 945 946 rc = htab_bolt_mapping(start, end, __pa(start), 947 pgprot_val(prot), mmu_linear_psize, 948 mmu_kernel_ssize); 949 950 if (rc < 0) { 951 int rc2 = htab_remove_mapping(start, end, mmu_linear_psize, 952 mmu_kernel_ssize); 953 BUG_ON(rc2 && (rc2 != -ENOENT)); 954 } 955 return rc; 956 } 957 958 int hash__remove_section_mapping(unsigned long start, unsigned long end) 959 { 960 int rc = htab_remove_mapping(start, end, mmu_linear_psize, 961 mmu_kernel_ssize); 962 963 if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC) 964 pr_warn("Hash collision while resizing HPT\n"); 965 966 return rc; 967 } 968 #endif /* CONFIG_MEMORY_HOTPLUG */ 969 970 static void __init hash_init_partition_table(phys_addr_t hash_table, 971 unsigned long htab_size) 972 { 973 mmu_partition_table_init(); 974 975 /* 976 * PS field (VRMA page size) is not used for LPID 0, hence set to 0. 977 * For now, UPRT is 0 and we have no segment table. 978 */ 979 htab_size = __ilog2(htab_size) - 18; 980 mmu_partition_table_set_entry(0, hash_table | htab_size, 0, false); 981 pr_info("Partition table %p\n", partition_tb); 982 } 983 984 static void __init htab_initialize(void) 985 { 986 unsigned long table; 987 unsigned long pteg_count; 988 unsigned long prot; 989 phys_addr_t base = 0, size = 0, end; 990 u64 i; 991 992 DBG(" -> htab_initialize()\n"); 993 994 if (mmu_has_feature(MMU_FTR_1T_SEGMENT)) { 995 mmu_kernel_ssize = MMU_SEGSIZE_1T; 996 mmu_highuser_ssize = MMU_SEGSIZE_1T; 997 printk(KERN_INFO "Using 1TB segments\n"); 998 } 999 1000 if (stress_slb_enabled) 1001 static_branch_enable(&stress_slb_key); 1002 1003 /* 1004 * Calculate the required size of the htab. We want the number of 1005 * PTEGs to equal one half the number of real pages. 1006 */ 1007 htab_size_bytes = htab_get_table_size(); 1008 pteg_count = htab_size_bytes >> 7; 1009 1010 htab_hash_mask = pteg_count - 1; 1011 1012 if (firmware_has_feature(FW_FEATURE_LPAR) || 1013 firmware_has_feature(FW_FEATURE_PS3_LV1)) { 1014 /* Using a hypervisor which owns the htab */ 1015 htab_address = NULL; 1016 _SDR1 = 0; 1017 #ifdef CONFIG_FA_DUMP 1018 /* 1019 * If firmware assisted dump is active firmware preserves 1020 * the contents of htab along with entire partition memory. 1021 * Clear the htab if firmware assisted dump is active so 1022 * that we dont end up using old mappings. 1023 */ 1024 if (is_fadump_active() && mmu_hash_ops.hpte_clear_all) 1025 mmu_hash_ops.hpte_clear_all(); 1026 #endif 1027 } else { 1028 unsigned long limit = MEMBLOCK_ALLOC_ANYWHERE; 1029 1030 #ifdef CONFIG_PPC_CELL 1031 /* 1032 * Cell may require the hash table down low when using the 1033 * Axon IOMMU in order to fit the dynamic region over it, see 1034 * comments in cell/iommu.c 1035 */ 1036 if (fdt_subnode_offset(initial_boot_params, 0, "axon") > 0) { 1037 limit = 0x80000000; 1038 pr_info("Hash table forced below 2G for Axon IOMMU\n"); 1039 } 1040 #endif /* CONFIG_PPC_CELL */ 1041 1042 table = memblock_phys_alloc_range(htab_size_bytes, 1043 htab_size_bytes, 1044 0, limit); 1045 if (!table) 1046 panic("ERROR: Failed to allocate %pa bytes below %pa\n", 1047 &htab_size_bytes, &limit); 1048 1049 DBG("Hash table allocated at %lx, size: %lx\n", table, 1050 htab_size_bytes); 1051 1052 htab_address = __va(table); 1053 1054 /* htab absolute addr + encoded htabsize */ 1055 _SDR1 = table + __ilog2(htab_size_bytes) - 18; 1056 1057 /* Initialize the HPT with no entries */ 1058 memset((void *)table, 0, htab_size_bytes); 1059 1060 if (!cpu_has_feature(CPU_FTR_ARCH_300)) 1061 /* Set SDR1 */ 1062 mtspr(SPRN_SDR1, _SDR1); 1063 else 1064 hash_init_partition_table(table, htab_size_bytes); 1065 } 1066 1067 prot = pgprot_val(PAGE_KERNEL); 1068 1069 #ifdef CONFIG_DEBUG_PAGEALLOC 1070 if (debug_pagealloc_enabled()) { 1071 linear_map_hash_count = memblock_end_of_DRAM() >> PAGE_SHIFT; 1072 linear_map_hash_slots = memblock_alloc_try_nid( 1073 linear_map_hash_count, 1, MEMBLOCK_LOW_LIMIT, 1074 ppc64_rma_size, NUMA_NO_NODE); 1075 if (!linear_map_hash_slots) 1076 panic("%s: Failed to allocate %lu bytes max_addr=%pa\n", 1077 __func__, linear_map_hash_count, &ppc64_rma_size); 1078 } 1079 #endif /* CONFIG_DEBUG_PAGEALLOC */ 1080 1081 /* create bolted the linear mapping in the hash table */ 1082 for_each_mem_range(i, &base, &end) { 1083 size = end - base; 1084 base = (unsigned long)__va(base); 1085 1086 DBG("creating mapping for region: %lx..%lx (prot: %lx)\n", 1087 base, size, prot); 1088 1089 if ((base + size) >= H_VMALLOC_START) { 1090 pr_warn("Outside the supported range\n"); 1091 continue; 1092 } 1093 1094 BUG_ON(htab_bolt_mapping(base, base + size, __pa(base), 1095 prot, mmu_linear_psize, mmu_kernel_ssize)); 1096 } 1097 memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE); 1098 1099 /* 1100 * If we have a memory_limit and we've allocated TCEs then we need to 1101 * explicitly map the TCE area at the top of RAM. We also cope with the 1102 * case that the TCEs start below memory_limit. 1103 * tce_alloc_start/end are 16MB aligned so the mapping should work 1104 * for either 4K or 16MB pages. 1105 */ 1106 if (tce_alloc_start) { 1107 tce_alloc_start = (unsigned long)__va(tce_alloc_start); 1108 tce_alloc_end = (unsigned long)__va(tce_alloc_end); 1109 1110 if (base + size >= tce_alloc_start) 1111 tce_alloc_start = base + size + 1; 1112 1113 BUG_ON(htab_bolt_mapping(tce_alloc_start, tce_alloc_end, 1114 __pa(tce_alloc_start), prot, 1115 mmu_linear_psize, mmu_kernel_ssize)); 1116 } 1117 1118 1119 DBG(" <- htab_initialize()\n"); 1120 } 1121 #undef KB 1122 #undef MB 1123 1124 void __init hash__early_init_devtree(void) 1125 { 1126 /* Initialize segment sizes */ 1127 of_scan_flat_dt(htab_dt_scan_seg_sizes, NULL); 1128 1129 /* Initialize page sizes */ 1130 htab_scan_page_sizes(); 1131 } 1132 1133 static struct hash_mm_context init_hash_mm_context; 1134 void __init hash__early_init_mmu(void) 1135 { 1136 #ifndef CONFIG_PPC_64K_PAGES 1137 /* 1138 * We have code in __hash_page_4K() and elsewhere, which assumes it can 1139 * do the following: 1140 * new_pte |= (slot << H_PAGE_F_GIX_SHIFT) & (H_PAGE_F_SECOND | H_PAGE_F_GIX); 1141 * 1142 * Where the slot number is between 0-15, and values of 8-15 indicate 1143 * the secondary bucket. For that code to work H_PAGE_F_SECOND and 1144 * H_PAGE_F_GIX must occupy four contiguous bits in the PTE, and 1145 * H_PAGE_F_SECOND must be placed above H_PAGE_F_GIX. Assert that here 1146 * with a BUILD_BUG_ON(). 1147 */ 1148 BUILD_BUG_ON(H_PAGE_F_SECOND != (1ul << (H_PAGE_F_GIX_SHIFT + 3))); 1149 #endif /* CONFIG_PPC_64K_PAGES */ 1150 1151 htab_init_page_sizes(); 1152 1153 /* 1154 * initialize page table size 1155 */ 1156 __pte_frag_nr = H_PTE_FRAG_NR; 1157 __pte_frag_size_shift = H_PTE_FRAG_SIZE_SHIFT; 1158 __pmd_frag_nr = H_PMD_FRAG_NR; 1159 __pmd_frag_size_shift = H_PMD_FRAG_SIZE_SHIFT; 1160 1161 __pte_index_size = H_PTE_INDEX_SIZE; 1162 __pmd_index_size = H_PMD_INDEX_SIZE; 1163 __pud_index_size = H_PUD_INDEX_SIZE; 1164 __pgd_index_size = H_PGD_INDEX_SIZE; 1165 __pud_cache_index = H_PUD_CACHE_INDEX; 1166 __pte_table_size = H_PTE_TABLE_SIZE; 1167 __pmd_table_size = H_PMD_TABLE_SIZE; 1168 __pud_table_size = H_PUD_TABLE_SIZE; 1169 __pgd_table_size = H_PGD_TABLE_SIZE; 1170 /* 1171 * 4k use hugepd format, so for hash set then to 1172 * zero 1173 */ 1174 __pmd_val_bits = HASH_PMD_VAL_BITS; 1175 __pud_val_bits = HASH_PUD_VAL_BITS; 1176 __pgd_val_bits = HASH_PGD_VAL_BITS; 1177 1178 __kernel_virt_start = H_KERN_VIRT_START; 1179 __vmalloc_start = H_VMALLOC_START; 1180 __vmalloc_end = H_VMALLOC_END; 1181 __kernel_io_start = H_KERN_IO_START; 1182 __kernel_io_end = H_KERN_IO_END; 1183 vmemmap = (struct page *)H_VMEMMAP_START; 1184 ioremap_bot = IOREMAP_BASE; 1185 1186 #ifdef CONFIG_PCI 1187 pci_io_base = ISA_IO_BASE; 1188 #endif 1189 1190 /* Select appropriate backend */ 1191 if (firmware_has_feature(FW_FEATURE_PS3_LV1)) 1192 ps3_early_mm_init(); 1193 else if (firmware_has_feature(FW_FEATURE_LPAR)) 1194 hpte_init_pseries(); 1195 else if (IS_ENABLED(CONFIG_PPC_HASH_MMU_NATIVE)) 1196 hpte_init_native(); 1197 1198 if (!mmu_hash_ops.hpte_insert) 1199 panic("hash__early_init_mmu: No MMU hash ops defined!\n"); 1200 1201 /* 1202 * Initialize the MMU Hash table and create the linear mapping 1203 * of memory. Has to be done before SLB initialization as this is 1204 * currently where the page size encoding is obtained. 1205 */ 1206 htab_initialize(); 1207 1208 init_mm.context.hash_context = &init_hash_mm_context; 1209 mm_ctx_set_slb_addr_limit(&init_mm.context, SLB_ADDR_LIMIT_DEFAULT); 1210 1211 pr_info("Initializing hash mmu with SLB\n"); 1212 /* Initialize SLB management */ 1213 slb_initialize(); 1214 1215 if (cpu_has_feature(CPU_FTR_ARCH_206) 1216 && cpu_has_feature(CPU_FTR_HVMODE)) 1217 tlbiel_all(); 1218 } 1219 1220 #ifdef CONFIG_SMP 1221 void hash__early_init_mmu_secondary(void) 1222 { 1223 /* Initialize hash table for that CPU */ 1224 if (!firmware_has_feature(FW_FEATURE_LPAR)) { 1225 1226 if (!cpu_has_feature(CPU_FTR_ARCH_300)) 1227 mtspr(SPRN_SDR1, _SDR1); 1228 else 1229 set_ptcr_when_no_uv(__pa(partition_tb) | 1230 (PATB_SIZE_SHIFT - 12)); 1231 } 1232 /* Initialize SLB */ 1233 slb_initialize(); 1234 1235 if (cpu_has_feature(CPU_FTR_ARCH_206) 1236 && cpu_has_feature(CPU_FTR_HVMODE)) 1237 tlbiel_all(); 1238 1239 #ifdef CONFIG_PPC_MEM_KEYS 1240 if (mmu_has_feature(MMU_FTR_PKEY)) 1241 mtspr(SPRN_UAMOR, default_uamor); 1242 #endif 1243 } 1244 #endif /* CONFIG_SMP */ 1245 1246 /* 1247 * Called by asm hashtable.S for doing lazy icache flush 1248 */ 1249 unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap) 1250 { 1251 struct page *page; 1252 1253 if (!pfn_valid(pte_pfn(pte))) 1254 return pp; 1255 1256 page = pte_page(pte); 1257 1258 /* page is dirty */ 1259 if (!test_bit(PG_dcache_clean, &page->flags) && !PageReserved(page)) { 1260 if (trap == INTERRUPT_INST_STORAGE) { 1261 flush_dcache_icache_page(page); 1262 set_bit(PG_dcache_clean, &page->flags); 1263 } else 1264 pp |= HPTE_R_N; 1265 } 1266 return pp; 1267 } 1268 1269 static unsigned int get_paca_psize(unsigned long addr) 1270 { 1271 unsigned char *psizes; 1272 unsigned long index, mask_index; 1273 1274 if (addr < SLICE_LOW_TOP) { 1275 psizes = get_paca()->mm_ctx_low_slices_psize; 1276 index = GET_LOW_SLICE_INDEX(addr); 1277 } else { 1278 psizes = get_paca()->mm_ctx_high_slices_psize; 1279 index = GET_HIGH_SLICE_INDEX(addr); 1280 } 1281 mask_index = index & 0x1; 1282 return (psizes[index >> 1] >> (mask_index * 4)) & 0xF; 1283 } 1284 1285 1286 /* 1287 * Demote a segment to using 4k pages. 1288 * For now this makes the whole process use 4k pages. 1289 */ 1290 #ifdef CONFIG_PPC_64K_PAGES 1291 void demote_segment_4k(struct mm_struct *mm, unsigned long addr) 1292 { 1293 if (get_slice_psize(mm, addr) == MMU_PAGE_4K) 1294 return; 1295 slice_set_range_psize(mm, addr, 1, MMU_PAGE_4K); 1296 copro_flush_all_slbs(mm); 1297 if ((get_paca_psize(addr) != MMU_PAGE_4K) && (current->mm == mm)) { 1298 1299 copy_mm_to_paca(mm); 1300 slb_flush_and_restore_bolted(); 1301 } 1302 } 1303 #endif /* CONFIG_PPC_64K_PAGES */ 1304 1305 #ifdef CONFIG_PPC_SUBPAGE_PROT 1306 /* 1307 * This looks up a 2-bit protection code for a 4k subpage of a 64k page. 1308 * Userspace sets the subpage permissions using the subpage_prot system call. 1309 * 1310 * Result is 0: full permissions, _PAGE_RW: read-only, 1311 * _PAGE_RWX: no access. 1312 */ 1313 static int subpage_protection(struct mm_struct *mm, unsigned long ea) 1314 { 1315 struct subpage_prot_table *spt = mm_ctx_subpage_prot(&mm->context); 1316 u32 spp = 0; 1317 u32 **sbpm, *sbpp; 1318 1319 if (!spt) 1320 return 0; 1321 1322 if (ea >= spt->maxaddr) 1323 return 0; 1324 if (ea < 0x100000000UL) { 1325 /* addresses below 4GB use spt->low_prot */ 1326 sbpm = spt->low_prot; 1327 } else { 1328 sbpm = spt->protptrs[ea >> SBP_L3_SHIFT]; 1329 if (!sbpm) 1330 return 0; 1331 } 1332 sbpp = sbpm[(ea >> SBP_L2_SHIFT) & (SBP_L2_COUNT - 1)]; 1333 if (!sbpp) 1334 return 0; 1335 spp = sbpp[(ea >> PAGE_SHIFT) & (SBP_L1_COUNT - 1)]; 1336 1337 /* extract 2-bit bitfield for this 4k subpage */ 1338 spp >>= 30 - 2 * ((ea >> 12) & 0xf); 1339 1340 /* 1341 * 0 -> full permission 1342 * 1 -> Read only 1343 * 2 -> no access. 1344 * We return the flag that need to be cleared. 1345 */ 1346 spp = ((spp & 2) ? _PAGE_RWX : 0) | ((spp & 1) ? _PAGE_WRITE : 0); 1347 return spp; 1348 } 1349 1350 #else /* CONFIG_PPC_SUBPAGE_PROT */ 1351 static inline int subpage_protection(struct mm_struct *mm, unsigned long ea) 1352 { 1353 return 0; 1354 } 1355 #endif 1356 1357 void hash_failure_debug(unsigned long ea, unsigned long access, 1358 unsigned long vsid, unsigned long trap, 1359 int ssize, int psize, int lpsize, unsigned long pte) 1360 { 1361 if (!printk_ratelimit()) 1362 return; 1363 pr_info("mm: Hashing failure ! EA=0x%lx access=0x%lx current=%s\n", 1364 ea, access, current->comm); 1365 pr_info(" trap=0x%lx vsid=0x%lx ssize=%d base psize=%d psize %d pte=0x%lx\n", 1366 trap, vsid, ssize, psize, lpsize, pte); 1367 } 1368 1369 static void check_paca_psize(unsigned long ea, struct mm_struct *mm, 1370 int psize, bool user_region) 1371 { 1372 if (user_region) { 1373 if (psize != get_paca_psize(ea)) { 1374 copy_mm_to_paca(mm); 1375 slb_flush_and_restore_bolted(); 1376 } 1377 } else if (get_paca()->vmalloc_sllp != 1378 mmu_psize_defs[mmu_vmalloc_psize].sllp) { 1379 get_paca()->vmalloc_sllp = 1380 mmu_psize_defs[mmu_vmalloc_psize].sllp; 1381 slb_vmalloc_update(); 1382 } 1383 } 1384 1385 /* 1386 * Result code is: 1387 * 0 - handled 1388 * 1 - normal page fault 1389 * -1 - critical hash insertion error 1390 * -2 - access not permitted by subpage protection mechanism 1391 */ 1392 int hash_page_mm(struct mm_struct *mm, unsigned long ea, 1393 unsigned long access, unsigned long trap, 1394 unsigned long flags) 1395 { 1396 bool is_thp; 1397 pgd_t *pgdir; 1398 unsigned long vsid; 1399 pte_t *ptep; 1400 unsigned hugeshift; 1401 int rc, user_region = 0; 1402 int psize, ssize; 1403 1404 DBG_LOW("hash_page(ea=%016lx, access=%lx, trap=%lx\n", 1405 ea, access, trap); 1406 trace_hash_fault(ea, access, trap); 1407 1408 /* Get region & vsid */ 1409 switch (get_region_id(ea)) { 1410 case USER_REGION_ID: 1411 user_region = 1; 1412 if (! mm) { 1413 DBG_LOW(" user region with no mm !\n"); 1414 rc = 1; 1415 goto bail; 1416 } 1417 psize = get_slice_psize(mm, ea); 1418 ssize = user_segment_size(ea); 1419 vsid = get_user_vsid(&mm->context, ea, ssize); 1420 break; 1421 case VMALLOC_REGION_ID: 1422 vsid = get_kernel_vsid(ea, mmu_kernel_ssize); 1423 psize = mmu_vmalloc_psize; 1424 ssize = mmu_kernel_ssize; 1425 flags |= HPTE_USE_KERNEL_KEY; 1426 break; 1427 1428 case IO_REGION_ID: 1429 vsid = get_kernel_vsid(ea, mmu_kernel_ssize); 1430 psize = mmu_io_psize; 1431 ssize = mmu_kernel_ssize; 1432 flags |= HPTE_USE_KERNEL_KEY; 1433 break; 1434 default: 1435 /* 1436 * Not a valid range 1437 * Send the problem up to do_page_fault() 1438 */ 1439 rc = 1; 1440 goto bail; 1441 } 1442 DBG_LOW(" mm=%p, mm->pgdir=%p, vsid=%016lx\n", mm, mm->pgd, vsid); 1443 1444 /* Bad address. */ 1445 if (!vsid) { 1446 DBG_LOW("Bad address!\n"); 1447 rc = 1; 1448 goto bail; 1449 } 1450 /* Get pgdir */ 1451 pgdir = mm->pgd; 1452 if (pgdir == NULL) { 1453 rc = 1; 1454 goto bail; 1455 } 1456 1457 /* Check CPU locality */ 1458 if (user_region && mm_is_thread_local(mm)) 1459 flags |= HPTE_LOCAL_UPDATE; 1460 1461 #ifndef CONFIG_PPC_64K_PAGES 1462 /* 1463 * If we use 4K pages and our psize is not 4K, then we might 1464 * be hitting a special driver mapping, and need to align the 1465 * address before we fetch the PTE. 1466 * 1467 * It could also be a hugepage mapping, in which case this is 1468 * not necessary, but it's not harmful, either. 1469 */ 1470 if (psize != MMU_PAGE_4K) 1471 ea &= ~((1ul << mmu_psize_defs[psize].shift) - 1); 1472 #endif /* CONFIG_PPC_64K_PAGES */ 1473 1474 /* Get PTE and page size from page tables */ 1475 ptep = find_linux_pte(pgdir, ea, &is_thp, &hugeshift); 1476 if (ptep == NULL || !pte_present(*ptep)) { 1477 DBG_LOW(" no PTE !\n"); 1478 rc = 1; 1479 goto bail; 1480 } 1481 1482 /* 1483 * Add _PAGE_PRESENT to the required access perm. If there are parallel 1484 * updates to the pte that can possibly clear _PAGE_PTE, catch that too. 1485 * 1486 * We can safely use the return pte address in rest of the function 1487 * because we do set H_PAGE_BUSY which prevents further updates to pte 1488 * from generic code. 1489 */ 1490 access |= _PAGE_PRESENT | _PAGE_PTE; 1491 1492 /* 1493 * Pre-check access permissions (will be re-checked atomically 1494 * in __hash_page_XX but this pre-check is a fast path 1495 */ 1496 if (!check_pte_access(access, pte_val(*ptep))) { 1497 DBG_LOW(" no access !\n"); 1498 rc = 1; 1499 goto bail; 1500 } 1501 1502 if (hugeshift) { 1503 if (is_thp) 1504 rc = __hash_page_thp(ea, access, vsid, (pmd_t *)ptep, 1505 trap, flags, ssize, psize); 1506 #ifdef CONFIG_HUGETLB_PAGE 1507 else 1508 rc = __hash_page_huge(ea, access, vsid, ptep, trap, 1509 flags, ssize, hugeshift, psize); 1510 #else 1511 else { 1512 /* 1513 * if we have hugeshift, and is not transhuge with 1514 * hugetlb disabled, something is really wrong. 1515 */ 1516 rc = 1; 1517 WARN_ON(1); 1518 } 1519 #endif 1520 if (current->mm == mm) 1521 check_paca_psize(ea, mm, psize, user_region); 1522 1523 goto bail; 1524 } 1525 1526 #ifndef CONFIG_PPC_64K_PAGES 1527 DBG_LOW(" i-pte: %016lx\n", pte_val(*ptep)); 1528 #else 1529 DBG_LOW(" i-pte: %016lx %016lx\n", pte_val(*ptep), 1530 pte_val(*(ptep + PTRS_PER_PTE))); 1531 #endif 1532 /* Do actual hashing */ 1533 #ifdef CONFIG_PPC_64K_PAGES 1534 /* If H_PAGE_4K_PFN is set, make sure this is a 4k segment */ 1535 if ((pte_val(*ptep) & H_PAGE_4K_PFN) && psize == MMU_PAGE_64K) { 1536 demote_segment_4k(mm, ea); 1537 psize = MMU_PAGE_4K; 1538 } 1539 1540 /* 1541 * If this PTE is non-cacheable and we have restrictions on 1542 * using non cacheable large pages, then we switch to 4k 1543 */ 1544 if (mmu_ci_restrictions && psize == MMU_PAGE_64K && pte_ci(*ptep)) { 1545 if (user_region) { 1546 demote_segment_4k(mm, ea); 1547 psize = MMU_PAGE_4K; 1548 } else if (ea < VMALLOC_END) { 1549 /* 1550 * some driver did a non-cacheable mapping 1551 * in vmalloc space, so switch vmalloc 1552 * to 4k pages 1553 */ 1554 printk(KERN_ALERT "Reducing vmalloc segment " 1555 "to 4kB pages because of " 1556 "non-cacheable mapping\n"); 1557 psize = mmu_vmalloc_psize = MMU_PAGE_4K; 1558 copro_flush_all_slbs(mm); 1559 } 1560 } 1561 1562 #endif /* CONFIG_PPC_64K_PAGES */ 1563 1564 if (current->mm == mm) 1565 check_paca_psize(ea, mm, psize, user_region); 1566 1567 #ifdef CONFIG_PPC_64K_PAGES 1568 if (psize == MMU_PAGE_64K) 1569 rc = __hash_page_64K(ea, access, vsid, ptep, trap, 1570 flags, ssize); 1571 else 1572 #endif /* CONFIG_PPC_64K_PAGES */ 1573 { 1574 int spp = subpage_protection(mm, ea); 1575 if (access & spp) 1576 rc = -2; 1577 else 1578 rc = __hash_page_4K(ea, access, vsid, ptep, trap, 1579 flags, ssize, spp); 1580 } 1581 1582 /* 1583 * Dump some info in case of hash insertion failure, they should 1584 * never happen so it is really useful to know if/when they do 1585 */ 1586 if (rc == -1) 1587 hash_failure_debug(ea, access, vsid, trap, ssize, psize, 1588 psize, pte_val(*ptep)); 1589 #ifndef CONFIG_PPC_64K_PAGES 1590 DBG_LOW(" o-pte: %016lx\n", pte_val(*ptep)); 1591 #else 1592 DBG_LOW(" o-pte: %016lx %016lx\n", pte_val(*ptep), 1593 pte_val(*(ptep + PTRS_PER_PTE))); 1594 #endif 1595 DBG_LOW(" -> rc=%d\n", rc); 1596 1597 bail: 1598 return rc; 1599 } 1600 EXPORT_SYMBOL_GPL(hash_page_mm); 1601 1602 int hash_page(unsigned long ea, unsigned long access, unsigned long trap, 1603 unsigned long dsisr) 1604 { 1605 unsigned long flags = 0; 1606 struct mm_struct *mm = current->mm; 1607 1608 if ((get_region_id(ea) == VMALLOC_REGION_ID) || 1609 (get_region_id(ea) == IO_REGION_ID)) 1610 mm = &init_mm; 1611 1612 if (dsisr & DSISR_NOHPTE) 1613 flags |= HPTE_NOHPTE_UPDATE; 1614 1615 return hash_page_mm(mm, ea, access, trap, flags); 1616 } 1617 EXPORT_SYMBOL_GPL(hash_page); 1618 1619 DEFINE_INTERRUPT_HANDLER(do_hash_fault) 1620 { 1621 unsigned long ea = regs->dar; 1622 unsigned long dsisr = regs->dsisr; 1623 unsigned long access = _PAGE_PRESENT | _PAGE_READ; 1624 unsigned long flags = 0; 1625 struct mm_struct *mm; 1626 unsigned int region_id; 1627 long err; 1628 1629 if (unlikely(dsisr & (DSISR_BAD_FAULT_64S | DSISR_KEYFAULT))) { 1630 hash__do_page_fault(regs); 1631 return; 1632 } 1633 1634 region_id = get_region_id(ea); 1635 if ((region_id == VMALLOC_REGION_ID) || (region_id == IO_REGION_ID)) 1636 mm = &init_mm; 1637 else 1638 mm = current->mm; 1639 1640 if (dsisr & DSISR_NOHPTE) 1641 flags |= HPTE_NOHPTE_UPDATE; 1642 1643 if (dsisr & DSISR_ISSTORE) 1644 access |= _PAGE_WRITE; 1645 /* 1646 * We set _PAGE_PRIVILEGED only when 1647 * kernel mode access kernel space. 1648 * 1649 * _PAGE_PRIVILEGED is NOT set 1650 * 1) when kernel mode access user space 1651 * 2) user space access kernel space. 1652 */ 1653 access |= _PAGE_PRIVILEGED; 1654 if (user_mode(regs) || (region_id == USER_REGION_ID)) 1655 access &= ~_PAGE_PRIVILEGED; 1656 1657 if (TRAP(regs) == INTERRUPT_INST_STORAGE) 1658 access |= _PAGE_EXEC; 1659 1660 err = hash_page_mm(mm, ea, access, TRAP(regs), flags); 1661 if (unlikely(err < 0)) { 1662 // failed to insert a hash PTE due to an hypervisor error 1663 if (user_mode(regs)) { 1664 if (IS_ENABLED(CONFIG_PPC_SUBPAGE_PROT) && err == -2) 1665 _exception(SIGSEGV, regs, SEGV_ACCERR, ea); 1666 else 1667 _exception(SIGBUS, regs, BUS_ADRERR, ea); 1668 } else { 1669 bad_page_fault(regs, SIGBUS); 1670 } 1671 err = 0; 1672 1673 } else if (err) { 1674 hash__do_page_fault(regs); 1675 } 1676 } 1677 1678 static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) 1679 { 1680 int psize = get_slice_psize(mm, ea); 1681 1682 /* We only prefault standard pages for now */ 1683 if (unlikely(psize != mm_ctx_user_psize(&mm->context))) 1684 return false; 1685 1686 /* 1687 * Don't prefault if subpage protection is enabled for the EA. 1688 */ 1689 if (unlikely((psize == MMU_PAGE_4K) && subpage_protection(mm, ea))) 1690 return false; 1691 1692 return true; 1693 } 1694 1695 static void hash_preload(struct mm_struct *mm, pte_t *ptep, unsigned long ea, 1696 bool is_exec, unsigned long trap) 1697 { 1698 unsigned long vsid; 1699 pgd_t *pgdir; 1700 int rc, ssize, update_flags = 0; 1701 unsigned long access = _PAGE_PRESENT | _PAGE_READ | (is_exec ? _PAGE_EXEC : 0); 1702 unsigned long flags; 1703 1704 BUG_ON(get_region_id(ea) != USER_REGION_ID); 1705 1706 if (!should_hash_preload(mm, ea)) 1707 return; 1708 1709 DBG_LOW("hash_preload(mm=%p, mm->pgdir=%p, ea=%016lx, access=%lx," 1710 " trap=%lx\n", mm, mm->pgd, ea, access, trap); 1711 1712 /* Get Linux PTE if available */ 1713 pgdir = mm->pgd; 1714 if (pgdir == NULL) 1715 return; 1716 1717 /* Get VSID */ 1718 ssize = user_segment_size(ea); 1719 vsid = get_user_vsid(&mm->context, ea, ssize); 1720 if (!vsid) 1721 return; 1722 1723 #ifdef CONFIG_PPC_64K_PAGES 1724 /* If either H_PAGE_4K_PFN or cache inhibited is set (and we are on 1725 * a 64K kernel), then we don't preload, hash_page() will take 1726 * care of it once we actually try to access the page. 1727 * That way we don't have to duplicate all of the logic for segment 1728 * page size demotion here 1729 * Called with PTL held, hence can be sure the value won't change in 1730 * between. 1731 */ 1732 if ((pte_val(*ptep) & H_PAGE_4K_PFN) || pte_ci(*ptep)) 1733 return; 1734 #endif /* CONFIG_PPC_64K_PAGES */ 1735 1736 /* 1737 * __hash_page_* must run with interrupts off, including PMI interrupts 1738 * off, as it sets the H_PAGE_BUSY bit. 1739 * 1740 * It's otherwise possible for perf interrupts to hit at any time and 1741 * may take a hash fault reading the user stack, which could take a 1742 * hash miss and deadlock on the same H_PAGE_BUSY bit. 1743 * 1744 * Interrupts must also be off for the duration of the 1745 * mm_is_thread_local test and update, to prevent preempt running the 1746 * mm on another CPU (XXX: this may be racy vs kthread_use_mm). 1747 */ 1748 powerpc_local_irq_pmu_save(flags); 1749 1750 /* Is that local to this CPU ? */ 1751 if (mm_is_thread_local(mm)) 1752 update_flags |= HPTE_LOCAL_UPDATE; 1753 1754 /* Hash it in */ 1755 #ifdef CONFIG_PPC_64K_PAGES 1756 if (mm_ctx_user_psize(&mm->context) == MMU_PAGE_64K) 1757 rc = __hash_page_64K(ea, access, vsid, ptep, trap, 1758 update_flags, ssize); 1759 else 1760 #endif /* CONFIG_PPC_64K_PAGES */ 1761 rc = __hash_page_4K(ea, access, vsid, ptep, trap, update_flags, 1762 ssize, subpage_protection(mm, ea)); 1763 1764 /* Dump some info in case of hash insertion failure, they should 1765 * never happen so it is really useful to know if/when they do 1766 */ 1767 if (rc == -1) 1768 hash_failure_debug(ea, access, vsid, trap, ssize, 1769 mm_ctx_user_psize(&mm->context), 1770 mm_ctx_user_psize(&mm->context), 1771 pte_val(*ptep)); 1772 1773 powerpc_local_irq_pmu_restore(flags); 1774 } 1775 1776 /* 1777 * This is called at the end of handling a user page fault, when the 1778 * fault has been handled by updating a PTE in the linux page tables. 1779 * We use it to preload an HPTE into the hash table corresponding to 1780 * the updated linux PTE. 1781 * 1782 * This must always be called with the pte lock held. 1783 */ 1784 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 1785 pte_t *ptep) 1786 { 1787 /* 1788 * We don't need to worry about _PAGE_PRESENT here because we are 1789 * called with either mm->page_table_lock held or ptl lock held 1790 */ 1791 unsigned long trap; 1792 bool is_exec; 1793 1794 if (radix_enabled()) 1795 return; 1796 1797 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 1798 if (!pte_young(*ptep) || address >= TASK_SIZE) 1799 return; 1800 1801 /* 1802 * We try to figure out if we are coming from an instruction 1803 * access fault and pass that down to __hash_page so we avoid 1804 * double-faulting on execution of fresh text. We have to test 1805 * for regs NULL since init will get here first thing at boot. 1806 * 1807 * We also avoid filling the hash if not coming from a fault. 1808 */ 1809 1810 trap = current->thread.regs ? TRAP(current->thread.regs) : 0UL; 1811 switch (trap) { 1812 case 0x300: 1813 is_exec = false; 1814 break; 1815 case 0x400: 1816 is_exec = true; 1817 break; 1818 default: 1819 return; 1820 } 1821 1822 hash_preload(vma->vm_mm, ptep, address, is_exec, trap); 1823 } 1824 1825 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1826 static inline void tm_flush_hash_page(int local) 1827 { 1828 /* 1829 * Transactions are not aborted by tlbiel, only tlbie. Without, syncing a 1830 * page back to a block device w/PIO could pick up transactional data 1831 * (bad!) so we force an abort here. Before the sync the page will be 1832 * made read-only, which will flush_hash_page. BIG ISSUE here: if the 1833 * kernel uses a page from userspace without unmapping it first, it may 1834 * see the speculated version. 1835 */ 1836 if (local && cpu_has_feature(CPU_FTR_TM) && current->thread.regs && 1837 MSR_TM_ACTIVE(current->thread.regs->msr)) { 1838 tm_enable(); 1839 tm_abort(TM_CAUSE_TLBI); 1840 } 1841 } 1842 #else 1843 static inline void tm_flush_hash_page(int local) 1844 { 1845 } 1846 #endif 1847 1848 /* 1849 * Return the global hash slot, corresponding to the given PTE, which contains 1850 * the HPTE. 1851 */ 1852 unsigned long pte_get_hash_gslot(unsigned long vpn, unsigned long shift, 1853 int ssize, real_pte_t rpte, unsigned int subpg_index) 1854 { 1855 unsigned long hash, gslot, hidx; 1856 1857 hash = hpt_hash(vpn, shift, ssize); 1858 hidx = __rpte_to_hidx(rpte, subpg_index); 1859 if (hidx & _PTEIDX_SECONDARY) 1860 hash = ~hash; 1861 gslot = (hash & htab_hash_mask) * HPTES_PER_GROUP; 1862 gslot += hidx & _PTEIDX_GROUP_IX; 1863 return gslot; 1864 } 1865 1866 void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize, 1867 unsigned long flags) 1868 { 1869 unsigned long index, shift, gslot; 1870 int local = flags & HPTE_LOCAL_UPDATE; 1871 1872 DBG_LOW("flush_hash_page(vpn=%016lx)\n", vpn); 1873 pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) { 1874 gslot = pte_get_hash_gslot(vpn, shift, ssize, pte, index); 1875 DBG_LOW(" sub %ld: gslot=%lx\n", index, gslot); 1876 /* 1877 * We use same base page size and actual psize, because we don't 1878 * use these functions for hugepage 1879 */ 1880 mmu_hash_ops.hpte_invalidate(gslot, vpn, psize, psize, 1881 ssize, local); 1882 } pte_iterate_hashed_end(); 1883 1884 tm_flush_hash_page(local); 1885 } 1886 1887 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1888 void flush_hash_hugepage(unsigned long vsid, unsigned long addr, 1889 pmd_t *pmdp, unsigned int psize, int ssize, 1890 unsigned long flags) 1891 { 1892 int i, max_hpte_count, valid; 1893 unsigned long s_addr; 1894 unsigned char *hpte_slot_array; 1895 unsigned long hidx, shift, vpn, hash, slot; 1896 int local = flags & HPTE_LOCAL_UPDATE; 1897 1898 s_addr = addr & HPAGE_PMD_MASK; 1899 hpte_slot_array = get_hpte_slot_array(pmdp); 1900 /* 1901 * IF we try to do a HUGE PTE update after a withdraw is done. 1902 * we will find the below NULL. This happens when we do 1903 * split_huge_pmd 1904 */ 1905 if (!hpte_slot_array) 1906 return; 1907 1908 if (mmu_hash_ops.hugepage_invalidate) { 1909 mmu_hash_ops.hugepage_invalidate(vsid, s_addr, hpte_slot_array, 1910 psize, ssize, local); 1911 goto tm_abort; 1912 } 1913 /* 1914 * No bluk hpte removal support, invalidate each entry 1915 */ 1916 shift = mmu_psize_defs[psize].shift; 1917 max_hpte_count = HPAGE_PMD_SIZE >> shift; 1918 for (i = 0; i < max_hpte_count; i++) { 1919 /* 1920 * 8 bits per each hpte entries 1921 * 000| [ secondary group (one bit) | hidx (3 bits) | valid bit] 1922 */ 1923 valid = hpte_valid(hpte_slot_array, i); 1924 if (!valid) 1925 continue; 1926 hidx = hpte_hash_index(hpte_slot_array, i); 1927 1928 /* get the vpn */ 1929 addr = s_addr + (i * (1ul << shift)); 1930 vpn = hpt_vpn(addr, vsid, ssize); 1931 hash = hpt_hash(vpn, shift, ssize); 1932 if (hidx & _PTEIDX_SECONDARY) 1933 hash = ~hash; 1934 1935 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; 1936 slot += hidx & _PTEIDX_GROUP_IX; 1937 mmu_hash_ops.hpte_invalidate(slot, vpn, psize, 1938 MMU_PAGE_16M, ssize, local); 1939 } 1940 tm_abort: 1941 tm_flush_hash_page(local); 1942 } 1943 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1944 1945 void flush_hash_range(unsigned long number, int local) 1946 { 1947 if (mmu_hash_ops.flush_hash_range) 1948 mmu_hash_ops.flush_hash_range(number, local); 1949 else { 1950 int i; 1951 struct ppc64_tlb_batch *batch = 1952 this_cpu_ptr(&ppc64_tlb_batch); 1953 1954 for (i = 0; i < number; i++) 1955 flush_hash_page(batch->vpn[i], batch->pte[i], 1956 batch->psize, batch->ssize, local); 1957 } 1958 } 1959 1960 long hpte_insert_repeating(unsigned long hash, unsigned long vpn, 1961 unsigned long pa, unsigned long rflags, 1962 unsigned long vflags, int psize, int ssize) 1963 { 1964 unsigned long hpte_group; 1965 long slot; 1966 1967 repeat: 1968 hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP; 1969 1970 /* Insert into the hash table, primary slot */ 1971 slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, vflags, 1972 psize, psize, ssize); 1973 1974 /* Primary is full, try the secondary */ 1975 if (unlikely(slot == -1)) { 1976 hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP; 1977 slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, 1978 vflags | HPTE_V_SECONDARY, 1979 psize, psize, ssize); 1980 if (slot == -1) { 1981 if (mftb() & 0x1) 1982 hpte_group = (hash & htab_hash_mask) * 1983 HPTES_PER_GROUP; 1984 1985 mmu_hash_ops.hpte_remove(hpte_group); 1986 goto repeat; 1987 } 1988 } 1989 1990 return slot; 1991 } 1992 1993 #ifdef CONFIG_DEBUG_PAGEALLOC 1994 static void kernel_map_linear_page(unsigned long vaddr, unsigned long lmi) 1995 { 1996 unsigned long hash; 1997 unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize); 1998 unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize); 1999 unsigned long mode = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL), HPTE_USE_KERNEL_KEY); 2000 long ret; 2001 2002 hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize); 2003 2004 /* Don't create HPTE entries for bad address */ 2005 if (!vsid) 2006 return; 2007 2008 ret = hpte_insert_repeating(hash, vpn, __pa(vaddr), mode, 2009 HPTE_V_BOLTED, 2010 mmu_linear_psize, mmu_kernel_ssize); 2011 2012 BUG_ON (ret < 0); 2013 spin_lock(&linear_map_hash_lock); 2014 BUG_ON(linear_map_hash_slots[lmi] & 0x80); 2015 linear_map_hash_slots[lmi] = ret | 0x80; 2016 spin_unlock(&linear_map_hash_lock); 2017 } 2018 2019 static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi) 2020 { 2021 unsigned long hash, hidx, slot; 2022 unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize); 2023 unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize); 2024 2025 hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize); 2026 spin_lock(&linear_map_hash_lock); 2027 BUG_ON(!(linear_map_hash_slots[lmi] & 0x80)); 2028 hidx = linear_map_hash_slots[lmi] & 0x7f; 2029 linear_map_hash_slots[lmi] = 0; 2030 spin_unlock(&linear_map_hash_lock); 2031 if (hidx & _PTEIDX_SECONDARY) 2032 hash = ~hash; 2033 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; 2034 slot += hidx & _PTEIDX_GROUP_IX; 2035 mmu_hash_ops.hpte_invalidate(slot, vpn, mmu_linear_psize, 2036 mmu_linear_psize, 2037 mmu_kernel_ssize, 0); 2038 } 2039 2040 void hash__kernel_map_pages(struct page *page, int numpages, int enable) 2041 { 2042 unsigned long flags, vaddr, lmi; 2043 int i; 2044 2045 local_irq_save(flags); 2046 for (i = 0; i < numpages; i++, page++) { 2047 vaddr = (unsigned long)page_address(page); 2048 lmi = __pa(vaddr) >> PAGE_SHIFT; 2049 if (lmi >= linear_map_hash_count) 2050 continue; 2051 if (enable) 2052 kernel_map_linear_page(vaddr, lmi); 2053 else 2054 kernel_unmap_linear_page(vaddr, lmi); 2055 } 2056 local_irq_restore(flags); 2057 } 2058 #endif /* CONFIG_DEBUG_PAGEALLOC */ 2059 2060 void hash__setup_initial_memory_limit(phys_addr_t first_memblock_base, 2061 phys_addr_t first_memblock_size) 2062 { 2063 /* 2064 * We don't currently support the first MEMBLOCK not mapping 0 2065 * physical on those processors 2066 */ 2067 BUG_ON(first_memblock_base != 0); 2068 2069 /* 2070 * On virtualized systems the first entry is our RMA region aka VRMA, 2071 * non-virtualized 64-bit hash MMU systems don't have a limitation 2072 * on real mode access. 2073 * 2074 * For guests on platforms before POWER9, we clamp the it limit to 1G 2075 * to avoid some funky things such as RTAS bugs etc... 2076 * 2077 * On POWER9 we limit to 1TB in case the host erroneously told us that 2078 * the RMA was >1TB. Effective address bits 0:23 are treated as zero 2079 * (meaning the access is aliased to zero i.e. addr = addr % 1TB) 2080 * for virtual real mode addressing and so it doesn't make sense to 2081 * have an area larger than 1TB as it can't be addressed. 2082 */ 2083 if (!early_cpu_has_feature(CPU_FTR_HVMODE)) { 2084 ppc64_rma_size = first_memblock_size; 2085 if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) 2086 ppc64_rma_size = min_t(u64, ppc64_rma_size, 0x40000000); 2087 else 2088 ppc64_rma_size = min_t(u64, ppc64_rma_size, 2089 1UL << SID_SHIFT_1T); 2090 2091 /* Finally limit subsequent allocations */ 2092 memblock_set_current_limit(ppc64_rma_size); 2093 } else { 2094 ppc64_rma_size = ULONG_MAX; 2095 } 2096 } 2097 2098 #ifdef CONFIG_DEBUG_FS 2099 2100 static int hpt_order_get(void *data, u64 *val) 2101 { 2102 *val = ppc64_pft_size; 2103 return 0; 2104 } 2105 2106 static int hpt_order_set(void *data, u64 val) 2107 { 2108 int ret; 2109 2110 if (!mmu_hash_ops.resize_hpt) 2111 return -ENODEV; 2112 2113 cpus_read_lock(); 2114 ret = mmu_hash_ops.resize_hpt(val); 2115 cpus_read_unlock(); 2116 2117 return ret; 2118 } 2119 2120 DEFINE_DEBUGFS_ATTRIBUTE(fops_hpt_order, hpt_order_get, hpt_order_set, "%llu\n"); 2121 2122 static int __init hash64_debugfs(void) 2123 { 2124 debugfs_create_file("hpt_order", 0600, arch_debugfs_dir, NULL, 2125 &fops_hpt_order); 2126 return 0; 2127 } 2128 machine_device_initcall(pseries, hash64_debugfs); 2129 #endif /* CONFIG_DEBUG_FS */ 2130 2131 void __init print_system_hash_info(void) 2132 { 2133 pr_info("ppc64_pft_size = 0x%llx\n", ppc64_pft_size); 2134 2135 if (htab_hash_mask) 2136 pr_info("htab_hash_mask = 0x%lx\n", htab_hash_mask); 2137 } 2138 2139 unsigned long arch_randomize_brk(struct mm_struct *mm) 2140 { 2141 /* 2142 * If we are using 1TB segments and we are allowed to randomise 2143 * the heap, we can put it above 1TB so it is backed by a 1TB 2144 * segment. Otherwise the heap will be in the bottom 1TB 2145 * which always uses 256MB segments and this may result in a 2146 * performance penalty. 2147 */ 2148 if (is_32bit_task()) 2149 return randomize_page(mm->brk, SZ_32M); 2150 else if (!radix_enabled() && mmu_highuser_ssize == MMU_SEGSIZE_1T) 2151 return randomize_page(max_t(unsigned long, mm->brk, SZ_1T), SZ_1G); 2152 else 2153 return randomize_page(mm->brk, SZ_1G); 2154 } 2155