1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * 4 * Copyright 2016 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> 5 */ 6 7 #include <linux/types.h> 8 #include <linux/string.h> 9 #include <linux/kvm.h> 10 #include <linux/kvm_host.h> 11 #include <linux/anon_inodes.h> 12 #include <linux/file.h> 13 #include <linux/debugfs.h> 14 #include <linux/pgtable.h> 15 16 #include <asm/kvm_ppc.h> 17 #include <asm/kvm_book3s.h> 18 #include <asm/page.h> 19 #include <asm/mmu.h> 20 #include <asm/pgalloc.h> 21 #include <asm/pte-walk.h> 22 #include <asm/ultravisor.h> 23 #include <asm/kvm_book3s_uvmem.h> 24 #include <asm/plpar_wrappers.h> 25 26 /* 27 * Supported radix tree geometry. 28 * Like p9, we support either 5 or 9 bits at the first (lowest) level, 29 * for a page size of 64k or 4k. 30 */ 31 static int p9_supported_radix_bits[4] = { 5, 9, 9, 13 }; 32 33 unsigned long __kvmhv_copy_tofrom_guest_radix(int lpid, int pid, 34 gva_t eaddr, void *to, void *from, 35 unsigned long n) 36 { 37 int old_pid, old_lpid; 38 unsigned long quadrant, ret = n; 39 bool is_load = !!to; 40 41 /* Can't access quadrants 1 or 2 in non-HV mode, call the HV to do it */ 42 if (kvmhv_on_pseries()) 43 return plpar_hcall_norets(H_COPY_TOFROM_GUEST, lpid, pid, eaddr, 44 (to != NULL) ? __pa(to): 0, 45 (from != NULL) ? __pa(from): 0, n); 46 47 if (eaddr & (0xFFFUL << 52)) 48 return ret; 49 50 quadrant = 1; 51 if (!pid) 52 quadrant = 2; 53 if (is_load) 54 from = (void *) (eaddr | (quadrant << 62)); 55 else 56 to = (void *) (eaddr | (quadrant << 62)); 57 58 preempt_disable(); 59 60 asm volatile("hwsync" ::: "memory"); 61 isync(); 62 /* switch the lpid first to avoid running host with unallocated pid */ 63 old_lpid = mfspr(SPRN_LPID); 64 if (old_lpid != lpid) 65 mtspr(SPRN_LPID, lpid); 66 if (quadrant == 1) { 67 old_pid = mfspr(SPRN_PID); 68 if (old_pid != pid) 69 mtspr(SPRN_PID, pid); 70 } 71 isync(); 72 73 pagefault_disable(); 74 if (is_load) 75 ret = __copy_from_user_inatomic(to, (const void __user *)from, n); 76 else 77 ret = __copy_to_user_inatomic((void __user *)to, from, n); 78 pagefault_enable(); 79 80 asm volatile("hwsync" ::: "memory"); 81 isync(); 82 /* switch the pid first to avoid running host with unallocated pid */ 83 if (quadrant == 1 && pid != old_pid) 84 mtspr(SPRN_PID, old_pid); 85 if (lpid != old_lpid) 86 mtspr(SPRN_LPID, old_lpid); 87 isync(); 88 89 preempt_enable(); 90 91 return ret; 92 } 93 94 static long kvmhv_copy_tofrom_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, 95 void *to, void *from, unsigned long n) 96 { 97 int lpid = vcpu->kvm->arch.lpid; 98 int pid = vcpu->arch.pid; 99 100 /* This would cause a data segment intr so don't allow the access */ 101 if (eaddr & (0x3FFUL << 52)) 102 return -EINVAL; 103 104 /* Should we be using the nested lpid */ 105 if (vcpu->arch.nested) 106 lpid = vcpu->arch.nested->shadow_lpid; 107 108 /* If accessing quadrant 3 then pid is expected to be 0 */ 109 if (((eaddr >> 62) & 0x3) == 0x3) 110 pid = 0; 111 112 eaddr &= ~(0xFFFUL << 52); 113 114 return __kvmhv_copy_tofrom_guest_radix(lpid, pid, eaddr, to, from, n); 115 } 116 117 long kvmhv_copy_from_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, void *to, 118 unsigned long n) 119 { 120 long ret; 121 122 ret = kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, to, NULL, n); 123 if (ret > 0) 124 memset(to + (n - ret), 0, ret); 125 126 return ret; 127 } 128 129 long kvmhv_copy_to_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, void *from, 130 unsigned long n) 131 { 132 return kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, NULL, from, n); 133 } 134 135 int kvmppc_mmu_walk_radix_tree(struct kvm_vcpu *vcpu, gva_t eaddr, 136 struct kvmppc_pte *gpte, u64 root, 137 u64 *pte_ret_p) 138 { 139 struct kvm *kvm = vcpu->kvm; 140 int ret, level, ps; 141 unsigned long rts, bits, offset, index; 142 u64 pte, base, gpa; 143 __be64 rpte; 144 145 rts = ((root & RTS1_MASK) >> (RTS1_SHIFT - 3)) | 146 ((root & RTS2_MASK) >> RTS2_SHIFT); 147 bits = root & RPDS_MASK; 148 base = root & RPDB_MASK; 149 150 offset = rts + 31; 151 152 /* Current implementations only support 52-bit space */ 153 if (offset != 52) 154 return -EINVAL; 155 156 /* Walk each level of the radix tree */ 157 for (level = 3; level >= 0; --level) { 158 u64 addr; 159 /* Check a valid size */ 160 if (level && bits != p9_supported_radix_bits[level]) 161 return -EINVAL; 162 if (level == 0 && !(bits == 5 || bits == 9)) 163 return -EINVAL; 164 offset -= bits; 165 index = (eaddr >> offset) & ((1UL << bits) - 1); 166 /* Check that low bits of page table base are zero */ 167 if (base & ((1UL << (bits + 3)) - 1)) 168 return -EINVAL; 169 /* Read the entry from guest memory */ 170 addr = base + (index * sizeof(rpte)); 171 172 kvm_vcpu_srcu_read_lock(vcpu); 173 ret = kvm_read_guest(kvm, addr, &rpte, sizeof(rpte)); 174 kvm_vcpu_srcu_read_unlock(vcpu); 175 if (ret) { 176 if (pte_ret_p) 177 *pte_ret_p = addr; 178 return ret; 179 } 180 pte = __be64_to_cpu(rpte); 181 if (!(pte & _PAGE_PRESENT)) 182 return -ENOENT; 183 /* Check if a leaf entry */ 184 if (pte & _PAGE_PTE) 185 break; 186 /* Get ready to walk the next level */ 187 base = pte & RPDB_MASK; 188 bits = pte & RPDS_MASK; 189 } 190 191 /* Need a leaf at lowest level; 512GB pages not supported */ 192 if (level < 0 || level == 3) 193 return -EINVAL; 194 195 /* We found a valid leaf PTE */ 196 /* Offset is now log base 2 of the page size */ 197 gpa = pte & 0x01fffffffffff000ul; 198 if (gpa & ((1ul << offset) - 1)) 199 return -EINVAL; 200 gpa |= eaddr & ((1ul << offset) - 1); 201 for (ps = MMU_PAGE_4K; ps < MMU_PAGE_COUNT; ++ps) 202 if (offset == mmu_psize_defs[ps].shift) 203 break; 204 gpte->page_size = ps; 205 gpte->page_shift = offset; 206 207 gpte->eaddr = eaddr; 208 gpte->raddr = gpa; 209 210 /* Work out permissions */ 211 gpte->may_read = !!(pte & _PAGE_READ); 212 gpte->may_write = !!(pte & _PAGE_WRITE); 213 gpte->may_execute = !!(pte & _PAGE_EXEC); 214 215 gpte->rc = pte & (_PAGE_ACCESSED | _PAGE_DIRTY); 216 217 if (pte_ret_p) 218 *pte_ret_p = pte; 219 220 return 0; 221 } 222 223 /* 224 * Used to walk a partition or process table radix tree in guest memory 225 * Note: We exploit the fact that a partition table and a process 226 * table have the same layout, a partition-scoped page table and a 227 * process-scoped page table have the same layout, and the 2nd 228 * doubleword of a partition table entry has the same layout as 229 * the PTCR register. 230 */ 231 int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr, 232 struct kvmppc_pte *gpte, u64 table, 233 int table_index, u64 *pte_ret_p) 234 { 235 struct kvm *kvm = vcpu->kvm; 236 int ret; 237 unsigned long size, ptbl, root; 238 struct prtb_entry entry; 239 240 if ((table & PRTS_MASK) > 24) 241 return -EINVAL; 242 size = 1ul << ((table & PRTS_MASK) + 12); 243 244 /* Is the table big enough to contain this entry? */ 245 if ((table_index * sizeof(entry)) >= size) 246 return -EINVAL; 247 248 /* Read the table to find the root of the radix tree */ 249 ptbl = (table & PRTB_MASK) + (table_index * sizeof(entry)); 250 kvm_vcpu_srcu_read_lock(vcpu); 251 ret = kvm_read_guest(kvm, ptbl, &entry, sizeof(entry)); 252 kvm_vcpu_srcu_read_unlock(vcpu); 253 if (ret) 254 return ret; 255 256 /* Root is stored in the first double word */ 257 root = be64_to_cpu(entry.prtb0); 258 259 return kvmppc_mmu_walk_radix_tree(vcpu, eaddr, gpte, root, pte_ret_p); 260 } 261 262 int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, 263 struct kvmppc_pte *gpte, bool data, bool iswrite) 264 { 265 u32 pid; 266 u64 pte; 267 int ret; 268 269 /* Work out effective PID */ 270 switch (eaddr >> 62) { 271 case 0: 272 pid = vcpu->arch.pid; 273 break; 274 case 3: 275 pid = 0; 276 break; 277 default: 278 return -EINVAL; 279 } 280 281 ret = kvmppc_mmu_radix_translate_table(vcpu, eaddr, gpte, 282 vcpu->kvm->arch.process_table, pid, &pte); 283 if (ret) 284 return ret; 285 286 /* Check privilege (applies only to process scoped translations) */ 287 if (kvmppc_get_msr(vcpu) & MSR_PR) { 288 if (pte & _PAGE_PRIVILEGED) { 289 gpte->may_read = 0; 290 gpte->may_write = 0; 291 gpte->may_execute = 0; 292 } 293 } else { 294 if (!(pte & _PAGE_PRIVILEGED)) { 295 /* Check AMR/IAMR to see if strict mode is in force */ 296 if (vcpu->arch.amr & (1ul << 62)) 297 gpte->may_read = 0; 298 if (vcpu->arch.amr & (1ul << 63)) 299 gpte->may_write = 0; 300 if (vcpu->arch.iamr & (1ul << 62)) 301 gpte->may_execute = 0; 302 } 303 } 304 305 return 0; 306 } 307 308 void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr, 309 unsigned int pshift, unsigned int lpid) 310 { 311 unsigned long psize = PAGE_SIZE; 312 int psi; 313 long rc; 314 unsigned long rb; 315 316 if (pshift) 317 psize = 1UL << pshift; 318 else 319 pshift = PAGE_SHIFT; 320 321 addr &= ~(psize - 1); 322 323 if (!kvmhv_on_pseries()) { 324 radix__flush_tlb_lpid_page(lpid, addr, psize); 325 return; 326 } 327 328 psi = shift_to_mmu_psize(pshift); 329 330 if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE)) { 331 rb = addr | (mmu_get_ap(psi) << PPC_BITLSHIFT(58)); 332 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(0, 0, 1), 333 lpid, rb); 334 } else { 335 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU, 336 H_RPTI_TYPE_NESTED | 337 H_RPTI_TYPE_TLB, 338 psize_to_rpti_pgsize(psi), 339 addr, addr + psize); 340 } 341 342 if (rc) 343 pr_err("KVM: TLB page invalidation hcall failed, rc=%ld\n", rc); 344 } 345 346 static void kvmppc_radix_flush_pwc(struct kvm *kvm, unsigned int lpid) 347 { 348 long rc; 349 350 if (!kvmhv_on_pseries()) { 351 radix__flush_pwc_lpid(lpid); 352 return; 353 } 354 355 if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE)) 356 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(1, 0, 1), 357 lpid, TLBIEL_INVAL_SET_LPID); 358 else 359 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU, 360 H_RPTI_TYPE_NESTED | 361 H_RPTI_TYPE_PWC, H_RPTI_PAGE_ALL, 362 0, -1UL); 363 if (rc) 364 pr_err("KVM: TLB PWC invalidation hcall failed, rc=%ld\n", rc); 365 } 366 367 static unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep, 368 unsigned long clr, unsigned long set, 369 unsigned long addr, unsigned int shift) 370 { 371 return __radix_pte_update(ptep, clr, set); 372 } 373 374 static void kvmppc_radix_set_pte_at(struct kvm *kvm, unsigned long addr, 375 pte_t *ptep, pte_t pte) 376 { 377 radix__set_pte_at(kvm->mm, addr, ptep, pte, 0); 378 } 379 380 static struct kmem_cache *kvm_pte_cache; 381 static struct kmem_cache *kvm_pmd_cache; 382 383 static pte_t *kvmppc_pte_alloc(void) 384 { 385 pte_t *pte; 386 387 pte = kmem_cache_alloc(kvm_pte_cache, GFP_KERNEL); 388 /* pmd_populate() will only reference _pa(pte). */ 389 kmemleak_ignore(pte); 390 391 return pte; 392 } 393 394 static void kvmppc_pte_free(pte_t *ptep) 395 { 396 kmem_cache_free(kvm_pte_cache, ptep); 397 } 398 399 static pmd_t *kvmppc_pmd_alloc(void) 400 { 401 pmd_t *pmd; 402 403 pmd = kmem_cache_alloc(kvm_pmd_cache, GFP_KERNEL); 404 /* pud_populate() will only reference _pa(pmd). */ 405 kmemleak_ignore(pmd); 406 407 return pmd; 408 } 409 410 static void kvmppc_pmd_free(pmd_t *pmdp) 411 { 412 kmem_cache_free(kvm_pmd_cache, pmdp); 413 } 414 415 /* Called with kvm->mmu_lock held */ 416 void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa, 417 unsigned int shift, 418 const struct kvm_memory_slot *memslot, 419 unsigned int lpid) 420 421 { 422 unsigned long old; 423 unsigned long gfn = gpa >> PAGE_SHIFT; 424 unsigned long page_size = PAGE_SIZE; 425 unsigned long hpa; 426 427 old = kvmppc_radix_update_pte(kvm, pte, ~0UL, 0, gpa, shift); 428 kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid); 429 430 /* The following only applies to L1 entries */ 431 if (lpid != kvm->arch.lpid) 432 return; 433 434 if (!memslot) { 435 memslot = gfn_to_memslot(kvm, gfn); 436 if (!memslot) 437 return; 438 } 439 if (shift) { /* 1GB or 2MB page */ 440 page_size = 1ul << shift; 441 if (shift == PMD_SHIFT) 442 kvm->stat.num_2M_pages--; 443 else if (shift == PUD_SHIFT) 444 kvm->stat.num_1G_pages--; 445 } 446 447 gpa &= ~(page_size - 1); 448 hpa = old & PTE_RPN_MASK; 449 kvmhv_remove_nest_rmap_range(kvm, memslot, gpa, hpa, page_size); 450 451 if ((old & _PAGE_DIRTY) && memslot->dirty_bitmap) 452 kvmppc_update_dirty_map(memslot, gfn, page_size); 453 } 454 455 /* 456 * kvmppc_free_p?d are used to free existing page tables, and recursively 457 * descend and clear and free children. 458 * Callers are responsible for flushing the PWC. 459 * 460 * When page tables are being unmapped/freed as part of page fault path 461 * (full == false), valid ptes are generally not expected; however, there 462 * is one situation where they arise, which is when dirty page logging is 463 * turned off for a memslot while the VM is running. The new memslot 464 * becomes visible to page faults before the memslot commit function 465 * gets to flush the memslot, which can lead to a 2MB page mapping being 466 * installed for a guest physical address where there are already 64kB 467 * (or 4kB) mappings (of sub-pages of the same 2MB page). 468 */ 469 static void kvmppc_unmap_free_pte(struct kvm *kvm, pte_t *pte, bool full, 470 unsigned int lpid) 471 { 472 if (full) { 473 memset(pte, 0, sizeof(long) << RADIX_PTE_INDEX_SIZE); 474 } else { 475 pte_t *p = pte; 476 unsigned long it; 477 478 for (it = 0; it < PTRS_PER_PTE; ++it, ++p) { 479 if (pte_val(*p) == 0) 480 continue; 481 kvmppc_unmap_pte(kvm, p, 482 pte_pfn(*p) << PAGE_SHIFT, 483 PAGE_SHIFT, NULL, lpid); 484 } 485 } 486 487 kvmppc_pte_free(pte); 488 } 489 490 static void kvmppc_unmap_free_pmd(struct kvm *kvm, pmd_t *pmd, bool full, 491 unsigned int lpid) 492 { 493 unsigned long im; 494 pmd_t *p = pmd; 495 496 for (im = 0; im < PTRS_PER_PMD; ++im, ++p) { 497 if (!pmd_present(*p)) 498 continue; 499 if (pmd_is_leaf(*p)) { 500 if (full) { 501 pmd_clear(p); 502 } else { 503 WARN_ON_ONCE(1); 504 kvmppc_unmap_pte(kvm, (pte_t *)p, 505 pte_pfn(*(pte_t *)p) << PAGE_SHIFT, 506 PMD_SHIFT, NULL, lpid); 507 } 508 } else { 509 pte_t *pte; 510 511 pte = pte_offset_map(p, 0); 512 kvmppc_unmap_free_pte(kvm, pte, full, lpid); 513 pmd_clear(p); 514 } 515 } 516 kvmppc_pmd_free(pmd); 517 } 518 519 static void kvmppc_unmap_free_pud(struct kvm *kvm, pud_t *pud, 520 unsigned int lpid) 521 { 522 unsigned long iu; 523 pud_t *p = pud; 524 525 for (iu = 0; iu < PTRS_PER_PUD; ++iu, ++p) { 526 if (!pud_present(*p)) 527 continue; 528 if (pud_is_leaf(*p)) { 529 pud_clear(p); 530 } else { 531 pmd_t *pmd; 532 533 pmd = pmd_offset(p, 0); 534 kvmppc_unmap_free_pmd(kvm, pmd, true, lpid); 535 pud_clear(p); 536 } 537 } 538 pud_free(kvm->mm, pud); 539 } 540 541 void kvmppc_free_pgtable_radix(struct kvm *kvm, pgd_t *pgd, unsigned int lpid) 542 { 543 unsigned long ig; 544 545 for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) { 546 p4d_t *p4d = p4d_offset(pgd, 0); 547 pud_t *pud; 548 549 if (!p4d_present(*p4d)) 550 continue; 551 pud = pud_offset(p4d, 0); 552 kvmppc_unmap_free_pud(kvm, pud, lpid); 553 p4d_clear(p4d); 554 } 555 } 556 557 void kvmppc_free_radix(struct kvm *kvm) 558 { 559 if (kvm->arch.pgtable) { 560 kvmppc_free_pgtable_radix(kvm, kvm->arch.pgtable, 561 kvm->arch.lpid); 562 pgd_free(kvm->mm, kvm->arch.pgtable); 563 kvm->arch.pgtable = NULL; 564 } 565 } 566 567 static void kvmppc_unmap_free_pmd_entry_table(struct kvm *kvm, pmd_t *pmd, 568 unsigned long gpa, unsigned int lpid) 569 { 570 pte_t *pte = pte_offset_kernel(pmd, 0); 571 572 /* 573 * Clearing the pmd entry then flushing the PWC ensures that the pte 574 * page no longer be cached by the MMU, so can be freed without 575 * flushing the PWC again. 576 */ 577 pmd_clear(pmd); 578 kvmppc_radix_flush_pwc(kvm, lpid); 579 580 kvmppc_unmap_free_pte(kvm, pte, false, lpid); 581 } 582 583 static void kvmppc_unmap_free_pud_entry_table(struct kvm *kvm, pud_t *pud, 584 unsigned long gpa, unsigned int lpid) 585 { 586 pmd_t *pmd = pmd_offset(pud, 0); 587 588 /* 589 * Clearing the pud entry then flushing the PWC ensures that the pmd 590 * page and any children pte pages will no longer be cached by the MMU, 591 * so can be freed without flushing the PWC again. 592 */ 593 pud_clear(pud); 594 kvmppc_radix_flush_pwc(kvm, lpid); 595 596 kvmppc_unmap_free_pmd(kvm, pmd, false, lpid); 597 } 598 599 /* 600 * There are a number of bits which may differ between different faults to 601 * the same partition scope entry. RC bits, in the course of cleaning and 602 * aging. And the write bit can change, either the access could have been 603 * upgraded, or a read fault could happen concurrently with a write fault 604 * that sets those bits first. 605 */ 606 #define PTE_BITS_MUST_MATCH (~(_PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)) 607 608 int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte, 609 unsigned long gpa, unsigned int level, 610 unsigned long mmu_seq, unsigned int lpid, 611 unsigned long *rmapp, struct rmap_nested **n_rmap) 612 { 613 pgd_t *pgd; 614 p4d_t *p4d; 615 pud_t *pud, *new_pud = NULL; 616 pmd_t *pmd, *new_pmd = NULL; 617 pte_t *ptep, *new_ptep = NULL; 618 int ret; 619 620 /* Traverse the guest's 2nd-level tree, allocate new levels needed */ 621 pgd = pgtable + pgd_index(gpa); 622 p4d = p4d_offset(pgd, gpa); 623 624 pud = NULL; 625 if (p4d_present(*p4d)) 626 pud = pud_offset(p4d, gpa); 627 else 628 new_pud = pud_alloc_one(kvm->mm, gpa); 629 630 pmd = NULL; 631 if (pud && pud_present(*pud) && !pud_is_leaf(*pud)) 632 pmd = pmd_offset(pud, gpa); 633 else if (level <= 1) 634 new_pmd = kvmppc_pmd_alloc(); 635 636 if (level == 0 && !(pmd && pmd_present(*pmd) && !pmd_is_leaf(*pmd))) 637 new_ptep = kvmppc_pte_alloc(); 638 639 /* Check if we might have been invalidated; let the guest retry if so */ 640 spin_lock(&kvm->mmu_lock); 641 ret = -EAGAIN; 642 if (mmu_notifier_retry(kvm, mmu_seq)) 643 goto out_unlock; 644 645 /* Now traverse again under the lock and change the tree */ 646 ret = -ENOMEM; 647 if (p4d_none(*p4d)) { 648 if (!new_pud) 649 goto out_unlock; 650 p4d_populate(kvm->mm, p4d, new_pud); 651 new_pud = NULL; 652 } 653 pud = pud_offset(p4d, gpa); 654 if (pud_is_leaf(*pud)) { 655 unsigned long hgpa = gpa & PUD_MASK; 656 657 /* Check if we raced and someone else has set the same thing */ 658 if (level == 2) { 659 if (pud_raw(*pud) == pte_raw(pte)) { 660 ret = 0; 661 goto out_unlock; 662 } 663 /* Valid 1GB page here already, add our extra bits */ 664 WARN_ON_ONCE((pud_val(*pud) ^ pte_val(pte)) & 665 PTE_BITS_MUST_MATCH); 666 kvmppc_radix_update_pte(kvm, (pte_t *)pud, 667 0, pte_val(pte), hgpa, PUD_SHIFT); 668 ret = 0; 669 goto out_unlock; 670 } 671 /* 672 * If we raced with another CPU which has just put 673 * a 1GB pte in after we saw a pmd page, try again. 674 */ 675 if (!new_pmd) { 676 ret = -EAGAIN; 677 goto out_unlock; 678 } 679 /* Valid 1GB page here already, remove it */ 680 kvmppc_unmap_pte(kvm, (pte_t *)pud, hgpa, PUD_SHIFT, NULL, 681 lpid); 682 } 683 if (level == 2) { 684 if (!pud_none(*pud)) { 685 /* 686 * There's a page table page here, but we wanted to 687 * install a large page, so remove and free the page 688 * table page. 689 */ 690 kvmppc_unmap_free_pud_entry_table(kvm, pud, gpa, lpid); 691 } 692 kvmppc_radix_set_pte_at(kvm, gpa, (pte_t *)pud, pte); 693 if (rmapp && n_rmap) 694 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap); 695 ret = 0; 696 goto out_unlock; 697 } 698 if (pud_none(*pud)) { 699 if (!new_pmd) 700 goto out_unlock; 701 pud_populate(kvm->mm, pud, new_pmd); 702 new_pmd = NULL; 703 } 704 pmd = pmd_offset(pud, gpa); 705 if (pmd_is_leaf(*pmd)) { 706 unsigned long lgpa = gpa & PMD_MASK; 707 708 /* Check if we raced and someone else has set the same thing */ 709 if (level == 1) { 710 if (pmd_raw(*pmd) == pte_raw(pte)) { 711 ret = 0; 712 goto out_unlock; 713 } 714 /* Valid 2MB page here already, add our extra bits */ 715 WARN_ON_ONCE((pmd_val(*pmd) ^ pte_val(pte)) & 716 PTE_BITS_MUST_MATCH); 717 kvmppc_radix_update_pte(kvm, pmdp_ptep(pmd), 718 0, pte_val(pte), lgpa, PMD_SHIFT); 719 ret = 0; 720 goto out_unlock; 721 } 722 723 /* 724 * If we raced with another CPU which has just put 725 * a 2MB pte in after we saw a pte page, try again. 726 */ 727 if (!new_ptep) { 728 ret = -EAGAIN; 729 goto out_unlock; 730 } 731 /* Valid 2MB page here already, remove it */ 732 kvmppc_unmap_pte(kvm, pmdp_ptep(pmd), lgpa, PMD_SHIFT, NULL, 733 lpid); 734 } 735 if (level == 1) { 736 if (!pmd_none(*pmd)) { 737 /* 738 * There's a page table page here, but we wanted to 739 * install a large page, so remove and free the page 740 * table page. 741 */ 742 kvmppc_unmap_free_pmd_entry_table(kvm, pmd, gpa, lpid); 743 } 744 kvmppc_radix_set_pte_at(kvm, gpa, pmdp_ptep(pmd), pte); 745 if (rmapp && n_rmap) 746 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap); 747 ret = 0; 748 goto out_unlock; 749 } 750 if (pmd_none(*pmd)) { 751 if (!new_ptep) 752 goto out_unlock; 753 pmd_populate(kvm->mm, pmd, new_ptep); 754 new_ptep = NULL; 755 } 756 ptep = pte_offset_kernel(pmd, gpa); 757 if (pte_present(*ptep)) { 758 /* Check if someone else set the same thing */ 759 if (pte_raw(*ptep) == pte_raw(pte)) { 760 ret = 0; 761 goto out_unlock; 762 } 763 /* Valid page here already, add our extra bits */ 764 WARN_ON_ONCE((pte_val(*ptep) ^ pte_val(pte)) & 765 PTE_BITS_MUST_MATCH); 766 kvmppc_radix_update_pte(kvm, ptep, 0, pte_val(pte), gpa, 0); 767 ret = 0; 768 goto out_unlock; 769 } 770 kvmppc_radix_set_pte_at(kvm, gpa, ptep, pte); 771 if (rmapp && n_rmap) 772 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap); 773 ret = 0; 774 775 out_unlock: 776 spin_unlock(&kvm->mmu_lock); 777 if (new_pud) 778 pud_free(kvm->mm, new_pud); 779 if (new_pmd) 780 kvmppc_pmd_free(new_pmd); 781 if (new_ptep) 782 kvmppc_pte_free(new_ptep); 783 return ret; 784 } 785 786 bool kvmppc_hv_handle_set_rc(struct kvm *kvm, bool nested, bool writing, 787 unsigned long gpa, unsigned int lpid) 788 { 789 unsigned long pgflags; 790 unsigned int shift; 791 pte_t *ptep; 792 793 /* 794 * Need to set an R or C bit in the 2nd-level tables; 795 * since we are just helping out the hardware here, 796 * it is sufficient to do what the hardware does. 797 */ 798 pgflags = _PAGE_ACCESSED; 799 if (writing) 800 pgflags |= _PAGE_DIRTY; 801 802 if (nested) 803 ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift); 804 else 805 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 806 807 if (ptep && pte_present(*ptep) && (!writing || pte_write(*ptep))) { 808 kvmppc_radix_update_pte(kvm, ptep, 0, pgflags, gpa, shift); 809 return true; 810 } 811 return false; 812 } 813 814 int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu, 815 unsigned long gpa, 816 struct kvm_memory_slot *memslot, 817 bool writing, bool kvm_ro, 818 pte_t *inserted_pte, unsigned int *levelp) 819 { 820 struct kvm *kvm = vcpu->kvm; 821 struct page *page = NULL; 822 unsigned long mmu_seq; 823 unsigned long hva, gfn = gpa >> PAGE_SHIFT; 824 bool upgrade_write = false; 825 bool *upgrade_p = &upgrade_write; 826 pte_t pte, *ptep; 827 unsigned int shift, level; 828 int ret; 829 bool large_enable; 830 831 /* used to check for invalidations in progress */ 832 mmu_seq = kvm->mmu_notifier_seq; 833 smp_rmb(); 834 835 /* 836 * Do a fast check first, since __gfn_to_pfn_memslot doesn't 837 * do it with !atomic && !async, which is how we call it. 838 * We always ask for write permission since the common case 839 * is that the page is writable. 840 */ 841 hva = gfn_to_hva_memslot(memslot, gfn); 842 if (!kvm_ro && get_user_page_fast_only(hva, FOLL_WRITE, &page)) { 843 upgrade_write = true; 844 } else { 845 unsigned long pfn; 846 847 /* Call KVM generic code to do the slow-path check */ 848 pfn = __gfn_to_pfn_memslot(memslot, gfn, false, NULL, 849 writing, upgrade_p, NULL); 850 if (is_error_noslot_pfn(pfn)) 851 return -EFAULT; 852 page = NULL; 853 if (pfn_valid(pfn)) { 854 page = pfn_to_page(pfn); 855 if (PageReserved(page)) 856 page = NULL; 857 } 858 } 859 860 /* 861 * Read the PTE from the process' radix tree and use that 862 * so we get the shift and attribute bits. 863 */ 864 spin_lock(&kvm->mmu_lock); 865 ptep = find_kvm_host_pte(kvm, mmu_seq, hva, &shift); 866 pte = __pte(0); 867 if (ptep) 868 pte = READ_ONCE(*ptep); 869 spin_unlock(&kvm->mmu_lock); 870 /* 871 * If the PTE disappeared temporarily due to a THP 872 * collapse, just return and let the guest try again. 873 */ 874 if (!pte_present(pte)) { 875 if (page) 876 put_page(page); 877 return RESUME_GUEST; 878 } 879 880 /* If we're logging dirty pages, always map single pages */ 881 large_enable = !(memslot->flags & KVM_MEM_LOG_DIRTY_PAGES); 882 883 /* Get pte level from shift/size */ 884 if (large_enable && shift == PUD_SHIFT && 885 (gpa & (PUD_SIZE - PAGE_SIZE)) == 886 (hva & (PUD_SIZE - PAGE_SIZE))) { 887 level = 2; 888 } else if (large_enable && shift == PMD_SHIFT && 889 (gpa & (PMD_SIZE - PAGE_SIZE)) == 890 (hva & (PMD_SIZE - PAGE_SIZE))) { 891 level = 1; 892 } else { 893 level = 0; 894 if (shift > PAGE_SHIFT) { 895 /* 896 * If the pte maps more than one page, bring over 897 * bits from the virtual address to get the real 898 * address of the specific single page we want. 899 */ 900 unsigned long rpnmask = (1ul << shift) - PAGE_SIZE; 901 pte = __pte(pte_val(pte) | (hva & rpnmask)); 902 } 903 } 904 905 pte = __pte(pte_val(pte) | _PAGE_EXEC | _PAGE_ACCESSED); 906 if (writing || upgrade_write) { 907 if (pte_val(pte) & _PAGE_WRITE) 908 pte = __pte(pte_val(pte) | _PAGE_DIRTY); 909 } else { 910 pte = __pte(pte_val(pte) & ~(_PAGE_WRITE | _PAGE_DIRTY)); 911 } 912 913 /* Allocate space in the tree and write the PTE */ 914 ret = kvmppc_create_pte(kvm, kvm->arch.pgtable, pte, gpa, level, 915 mmu_seq, kvm->arch.lpid, NULL, NULL); 916 if (inserted_pte) 917 *inserted_pte = pte; 918 if (levelp) 919 *levelp = level; 920 921 if (page) { 922 if (!ret && (pte_val(pte) & _PAGE_WRITE)) 923 set_page_dirty_lock(page); 924 put_page(page); 925 } 926 927 /* Increment number of large pages if we (successfully) inserted one */ 928 if (!ret) { 929 if (level == 1) 930 kvm->stat.num_2M_pages++; 931 else if (level == 2) 932 kvm->stat.num_1G_pages++; 933 } 934 935 return ret; 936 } 937 938 int kvmppc_book3s_radix_page_fault(struct kvm_vcpu *vcpu, 939 unsigned long ea, unsigned long dsisr) 940 { 941 struct kvm *kvm = vcpu->kvm; 942 unsigned long gpa, gfn; 943 struct kvm_memory_slot *memslot; 944 long ret; 945 bool writing = !!(dsisr & DSISR_ISSTORE); 946 bool kvm_ro = false; 947 948 /* Check for unusual errors */ 949 if (dsisr & DSISR_UNSUPP_MMU) { 950 pr_err("KVM: Got unsupported MMU fault\n"); 951 return -EFAULT; 952 } 953 if (dsisr & DSISR_BADACCESS) { 954 /* Reflect to the guest as DSI */ 955 pr_err("KVM: Got radix HV page fault with DSISR=%lx\n", dsisr); 956 kvmppc_core_queue_data_storage(vcpu, ea, dsisr); 957 return RESUME_GUEST; 958 } 959 960 /* Translate the logical address */ 961 gpa = vcpu->arch.fault_gpa & ~0xfffUL; 962 gpa &= ~0xF000000000000000ul; 963 gfn = gpa >> PAGE_SHIFT; 964 if (!(dsisr & DSISR_PRTABLE_FAULT)) 965 gpa |= ea & 0xfff; 966 967 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 968 return kvmppc_send_page_to_uv(kvm, gfn); 969 970 /* Get the corresponding memslot */ 971 memslot = gfn_to_memslot(kvm, gfn); 972 973 /* No memslot means it's an emulated MMIO region */ 974 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) { 975 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS | 976 DSISR_SET_RC)) { 977 /* 978 * Bad address in guest page table tree, or other 979 * unusual error - reflect it to the guest as DSI. 980 */ 981 kvmppc_core_queue_data_storage(vcpu, ea, dsisr); 982 return RESUME_GUEST; 983 } 984 return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing); 985 } 986 987 if (memslot->flags & KVM_MEM_READONLY) { 988 if (writing) { 989 /* give the guest a DSI */ 990 kvmppc_core_queue_data_storage(vcpu, ea, DSISR_ISSTORE | 991 DSISR_PROTFAULT); 992 return RESUME_GUEST; 993 } 994 kvm_ro = true; 995 } 996 997 /* Failed to set the reference/change bits */ 998 if (dsisr & DSISR_SET_RC) { 999 spin_lock(&kvm->mmu_lock); 1000 if (kvmppc_hv_handle_set_rc(kvm, false, writing, 1001 gpa, kvm->arch.lpid)) 1002 dsisr &= ~DSISR_SET_RC; 1003 spin_unlock(&kvm->mmu_lock); 1004 1005 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE | 1006 DSISR_PROTFAULT | DSISR_SET_RC))) 1007 return RESUME_GUEST; 1008 } 1009 1010 /* Try to insert a pte */ 1011 ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot, writing, 1012 kvm_ro, NULL, NULL); 1013 1014 if (ret == 0 || ret == -EAGAIN) 1015 ret = RESUME_GUEST; 1016 return ret; 1017 } 1018 1019 /* Called with kvm->mmu_lock held */ 1020 void kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, 1021 unsigned long gfn) 1022 { 1023 pte_t *ptep; 1024 unsigned long gpa = gfn << PAGE_SHIFT; 1025 unsigned int shift; 1026 1027 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) { 1028 uv_page_inval(kvm->arch.lpid, gpa, PAGE_SHIFT); 1029 return; 1030 } 1031 1032 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1033 if (ptep && pte_present(*ptep)) 1034 kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot, 1035 kvm->arch.lpid); 1036 } 1037 1038 /* Called with kvm->mmu_lock held */ 1039 bool kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, 1040 unsigned long gfn) 1041 { 1042 pte_t *ptep; 1043 unsigned long gpa = gfn << PAGE_SHIFT; 1044 unsigned int shift; 1045 bool ref = false; 1046 unsigned long old, *rmapp; 1047 1048 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1049 return ref; 1050 1051 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1052 if (ptep && pte_present(*ptep) && pte_young(*ptep)) { 1053 old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_ACCESSED, 0, 1054 gpa, shift); 1055 /* XXX need to flush tlb here? */ 1056 /* Also clear bit in ptes in shadow pgtable for nested guests */ 1057 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 1058 kvmhv_update_nest_rmap_rc_list(kvm, rmapp, _PAGE_ACCESSED, 0, 1059 old & PTE_RPN_MASK, 1060 1UL << shift); 1061 ref = true; 1062 } 1063 return ref; 1064 } 1065 1066 /* Called with kvm->mmu_lock held */ 1067 bool kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, 1068 unsigned long gfn) 1069 1070 { 1071 pte_t *ptep; 1072 unsigned long gpa = gfn << PAGE_SHIFT; 1073 unsigned int shift; 1074 bool ref = false; 1075 1076 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1077 return ref; 1078 1079 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1080 if (ptep && pte_present(*ptep) && pte_young(*ptep)) 1081 ref = true; 1082 return ref; 1083 } 1084 1085 /* Returns the number of PAGE_SIZE pages that are dirty */ 1086 static int kvm_radix_test_clear_dirty(struct kvm *kvm, 1087 struct kvm_memory_slot *memslot, int pagenum) 1088 { 1089 unsigned long gfn = memslot->base_gfn + pagenum; 1090 unsigned long gpa = gfn << PAGE_SHIFT; 1091 pte_t *ptep, pte; 1092 unsigned int shift; 1093 int ret = 0; 1094 unsigned long old, *rmapp; 1095 1096 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1097 return ret; 1098 1099 /* 1100 * For performance reasons we don't hold kvm->mmu_lock while walking the 1101 * partition scoped table. 1102 */ 1103 ptep = find_kvm_secondary_pte_unlocked(kvm, gpa, &shift); 1104 if (!ptep) 1105 return 0; 1106 1107 pte = READ_ONCE(*ptep); 1108 if (pte_present(pte) && pte_dirty(pte)) { 1109 spin_lock(&kvm->mmu_lock); 1110 /* 1111 * Recheck the pte again 1112 */ 1113 if (pte_val(pte) != pte_val(*ptep)) { 1114 /* 1115 * We have KVM_MEM_LOG_DIRTY_PAGES enabled. Hence we can 1116 * only find PAGE_SIZE pte entries here. We can continue 1117 * to use the pte addr returned by above page table 1118 * walk. 1119 */ 1120 if (!pte_present(*ptep) || !pte_dirty(*ptep)) { 1121 spin_unlock(&kvm->mmu_lock); 1122 return 0; 1123 } 1124 } 1125 1126 ret = 1; 1127 VM_BUG_ON(shift); 1128 old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_DIRTY, 0, 1129 gpa, shift); 1130 kvmppc_radix_tlbie_page(kvm, gpa, shift, kvm->arch.lpid); 1131 /* Also clear bit in ptes in shadow pgtable for nested guests */ 1132 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 1133 kvmhv_update_nest_rmap_rc_list(kvm, rmapp, _PAGE_DIRTY, 0, 1134 old & PTE_RPN_MASK, 1135 1UL << shift); 1136 spin_unlock(&kvm->mmu_lock); 1137 } 1138 return ret; 1139 } 1140 1141 long kvmppc_hv_get_dirty_log_radix(struct kvm *kvm, 1142 struct kvm_memory_slot *memslot, unsigned long *map) 1143 { 1144 unsigned long i, j; 1145 int npages; 1146 1147 for (i = 0; i < memslot->npages; i = j) { 1148 npages = kvm_radix_test_clear_dirty(kvm, memslot, i); 1149 1150 /* 1151 * Note that if npages > 0 then i must be a multiple of npages, 1152 * since huge pages are only used to back the guest at guest 1153 * real addresses that are a multiple of their size. 1154 * Since we have at most one PTE covering any given guest 1155 * real address, if npages > 1 we can skip to i + npages. 1156 */ 1157 j = i + 1; 1158 if (npages) { 1159 set_dirty_bits(map, i, npages); 1160 j = i + npages; 1161 } 1162 } 1163 return 0; 1164 } 1165 1166 void kvmppc_radix_flush_memslot(struct kvm *kvm, 1167 const struct kvm_memory_slot *memslot) 1168 { 1169 unsigned long n; 1170 pte_t *ptep; 1171 unsigned long gpa; 1172 unsigned int shift; 1173 1174 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_START) 1175 kvmppc_uvmem_drop_pages(memslot, kvm, true); 1176 1177 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1178 return; 1179 1180 gpa = memslot->base_gfn << PAGE_SHIFT; 1181 spin_lock(&kvm->mmu_lock); 1182 for (n = memslot->npages; n; --n) { 1183 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1184 if (ptep && pte_present(*ptep)) 1185 kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot, 1186 kvm->arch.lpid); 1187 gpa += PAGE_SIZE; 1188 } 1189 /* 1190 * Increase the mmu notifier sequence number to prevent any page 1191 * fault that read the memslot earlier from writing a PTE. 1192 */ 1193 kvm->mmu_notifier_seq++; 1194 spin_unlock(&kvm->mmu_lock); 1195 } 1196 1197 static void add_rmmu_ap_encoding(struct kvm_ppc_rmmu_info *info, 1198 int psize, int *indexp) 1199 { 1200 if (!mmu_psize_defs[psize].shift) 1201 return; 1202 info->ap_encodings[*indexp] = mmu_psize_defs[psize].shift | 1203 (mmu_psize_defs[psize].ap << 29); 1204 ++(*indexp); 1205 } 1206 1207 int kvmhv_get_rmmu_info(struct kvm *kvm, struct kvm_ppc_rmmu_info *info) 1208 { 1209 int i; 1210 1211 if (!radix_enabled()) 1212 return -EINVAL; 1213 memset(info, 0, sizeof(*info)); 1214 1215 /* 4k page size */ 1216 info->geometries[0].page_shift = 12; 1217 info->geometries[0].level_bits[0] = 9; 1218 for (i = 1; i < 4; ++i) 1219 info->geometries[0].level_bits[i] = p9_supported_radix_bits[i]; 1220 /* 64k page size */ 1221 info->geometries[1].page_shift = 16; 1222 for (i = 0; i < 4; ++i) 1223 info->geometries[1].level_bits[i] = p9_supported_radix_bits[i]; 1224 1225 i = 0; 1226 add_rmmu_ap_encoding(info, MMU_PAGE_4K, &i); 1227 add_rmmu_ap_encoding(info, MMU_PAGE_64K, &i); 1228 add_rmmu_ap_encoding(info, MMU_PAGE_2M, &i); 1229 add_rmmu_ap_encoding(info, MMU_PAGE_1G, &i); 1230 1231 return 0; 1232 } 1233 1234 int kvmppc_init_vm_radix(struct kvm *kvm) 1235 { 1236 kvm->arch.pgtable = pgd_alloc(kvm->mm); 1237 if (!kvm->arch.pgtable) 1238 return -ENOMEM; 1239 return 0; 1240 } 1241 1242 static void pte_ctor(void *addr) 1243 { 1244 memset(addr, 0, RADIX_PTE_TABLE_SIZE); 1245 } 1246 1247 static void pmd_ctor(void *addr) 1248 { 1249 memset(addr, 0, RADIX_PMD_TABLE_SIZE); 1250 } 1251 1252 struct debugfs_radix_state { 1253 struct kvm *kvm; 1254 struct mutex mutex; 1255 unsigned long gpa; 1256 int lpid; 1257 int chars_left; 1258 int buf_index; 1259 char buf[128]; 1260 u8 hdr; 1261 }; 1262 1263 static int debugfs_radix_open(struct inode *inode, struct file *file) 1264 { 1265 struct kvm *kvm = inode->i_private; 1266 struct debugfs_radix_state *p; 1267 1268 p = kzalloc(sizeof(*p), GFP_KERNEL); 1269 if (!p) 1270 return -ENOMEM; 1271 1272 kvm_get_kvm(kvm); 1273 p->kvm = kvm; 1274 mutex_init(&p->mutex); 1275 file->private_data = p; 1276 1277 return nonseekable_open(inode, file); 1278 } 1279 1280 static int debugfs_radix_release(struct inode *inode, struct file *file) 1281 { 1282 struct debugfs_radix_state *p = file->private_data; 1283 1284 kvm_put_kvm(p->kvm); 1285 kfree(p); 1286 return 0; 1287 } 1288 1289 static ssize_t debugfs_radix_read(struct file *file, char __user *buf, 1290 size_t len, loff_t *ppos) 1291 { 1292 struct debugfs_radix_state *p = file->private_data; 1293 ssize_t ret, r; 1294 unsigned long n; 1295 struct kvm *kvm; 1296 unsigned long gpa; 1297 pgd_t *pgt; 1298 struct kvm_nested_guest *nested; 1299 pgd_t *pgdp; 1300 p4d_t p4d, *p4dp; 1301 pud_t pud, *pudp; 1302 pmd_t pmd, *pmdp; 1303 pte_t *ptep; 1304 int shift; 1305 unsigned long pte; 1306 1307 kvm = p->kvm; 1308 if (!kvm_is_radix(kvm)) 1309 return 0; 1310 1311 ret = mutex_lock_interruptible(&p->mutex); 1312 if (ret) 1313 return ret; 1314 1315 if (p->chars_left) { 1316 n = p->chars_left; 1317 if (n > len) 1318 n = len; 1319 r = copy_to_user(buf, p->buf + p->buf_index, n); 1320 n -= r; 1321 p->chars_left -= n; 1322 p->buf_index += n; 1323 buf += n; 1324 len -= n; 1325 ret = n; 1326 if (r) { 1327 if (!n) 1328 ret = -EFAULT; 1329 goto out; 1330 } 1331 } 1332 1333 gpa = p->gpa; 1334 nested = NULL; 1335 pgt = NULL; 1336 while (len != 0 && p->lpid >= 0) { 1337 if (gpa >= RADIX_PGTABLE_RANGE) { 1338 gpa = 0; 1339 pgt = NULL; 1340 if (nested) { 1341 kvmhv_put_nested(nested); 1342 nested = NULL; 1343 } 1344 p->lpid = kvmhv_nested_next_lpid(kvm, p->lpid); 1345 p->hdr = 0; 1346 if (p->lpid < 0) 1347 break; 1348 } 1349 if (!pgt) { 1350 if (p->lpid == 0) { 1351 pgt = kvm->arch.pgtable; 1352 } else { 1353 nested = kvmhv_get_nested(kvm, p->lpid, false); 1354 if (!nested) { 1355 gpa = RADIX_PGTABLE_RANGE; 1356 continue; 1357 } 1358 pgt = nested->shadow_pgtable; 1359 } 1360 } 1361 n = 0; 1362 if (!p->hdr) { 1363 if (p->lpid > 0) 1364 n = scnprintf(p->buf, sizeof(p->buf), 1365 "\nNested LPID %d: ", p->lpid); 1366 n += scnprintf(p->buf + n, sizeof(p->buf) - n, 1367 "pgdir: %lx\n", (unsigned long)pgt); 1368 p->hdr = 1; 1369 goto copy; 1370 } 1371 1372 pgdp = pgt + pgd_index(gpa); 1373 p4dp = p4d_offset(pgdp, gpa); 1374 p4d = READ_ONCE(*p4dp); 1375 if (!(p4d_val(p4d) & _PAGE_PRESENT)) { 1376 gpa = (gpa & P4D_MASK) + P4D_SIZE; 1377 continue; 1378 } 1379 1380 pudp = pud_offset(&p4d, gpa); 1381 pud = READ_ONCE(*pudp); 1382 if (!(pud_val(pud) & _PAGE_PRESENT)) { 1383 gpa = (gpa & PUD_MASK) + PUD_SIZE; 1384 continue; 1385 } 1386 if (pud_val(pud) & _PAGE_PTE) { 1387 pte = pud_val(pud); 1388 shift = PUD_SHIFT; 1389 goto leaf; 1390 } 1391 1392 pmdp = pmd_offset(&pud, gpa); 1393 pmd = READ_ONCE(*pmdp); 1394 if (!(pmd_val(pmd) & _PAGE_PRESENT)) { 1395 gpa = (gpa & PMD_MASK) + PMD_SIZE; 1396 continue; 1397 } 1398 if (pmd_val(pmd) & _PAGE_PTE) { 1399 pte = pmd_val(pmd); 1400 shift = PMD_SHIFT; 1401 goto leaf; 1402 } 1403 1404 ptep = pte_offset_kernel(&pmd, gpa); 1405 pte = pte_val(READ_ONCE(*ptep)); 1406 if (!(pte & _PAGE_PRESENT)) { 1407 gpa += PAGE_SIZE; 1408 continue; 1409 } 1410 shift = PAGE_SHIFT; 1411 leaf: 1412 n = scnprintf(p->buf, sizeof(p->buf), 1413 " %lx: %lx %d\n", gpa, pte, shift); 1414 gpa += 1ul << shift; 1415 copy: 1416 p->chars_left = n; 1417 if (n > len) 1418 n = len; 1419 r = copy_to_user(buf, p->buf, n); 1420 n -= r; 1421 p->chars_left -= n; 1422 p->buf_index = n; 1423 buf += n; 1424 len -= n; 1425 ret += n; 1426 if (r) { 1427 if (!ret) 1428 ret = -EFAULT; 1429 break; 1430 } 1431 } 1432 p->gpa = gpa; 1433 if (nested) 1434 kvmhv_put_nested(nested); 1435 1436 out: 1437 mutex_unlock(&p->mutex); 1438 return ret; 1439 } 1440 1441 static ssize_t debugfs_radix_write(struct file *file, const char __user *buf, 1442 size_t len, loff_t *ppos) 1443 { 1444 return -EACCES; 1445 } 1446 1447 static const struct file_operations debugfs_radix_fops = { 1448 .owner = THIS_MODULE, 1449 .open = debugfs_radix_open, 1450 .release = debugfs_radix_release, 1451 .read = debugfs_radix_read, 1452 .write = debugfs_radix_write, 1453 .llseek = generic_file_llseek, 1454 }; 1455 1456 void kvmhv_radix_debugfs_init(struct kvm *kvm) 1457 { 1458 debugfs_create_file("radix", 0400, kvm->debugfs_dentry, kvm, 1459 &debugfs_radix_fops); 1460 } 1461 1462 int kvmppc_radix_init(void) 1463 { 1464 unsigned long size = sizeof(void *) << RADIX_PTE_INDEX_SIZE; 1465 1466 kvm_pte_cache = kmem_cache_create("kvm-pte", size, size, 0, pte_ctor); 1467 if (!kvm_pte_cache) 1468 return -ENOMEM; 1469 1470 size = sizeof(void *) << RADIX_PMD_INDEX_SIZE; 1471 1472 kvm_pmd_cache = kmem_cache_create("kvm-pmd", size, size, 0, pmd_ctor); 1473 if (!kvm_pmd_cache) { 1474 kmem_cache_destroy(kvm_pte_cache); 1475 return -ENOMEM; 1476 } 1477 1478 return 0; 1479 } 1480 1481 void kvmppc_radix_exit(void) 1482 { 1483 kmem_cache_destroy(kvm_pte_cache); 1484 kmem_cache_destroy(kvm_pmd_cache); 1485 } 1486