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