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