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