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