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 #include <asm/firmware.h> 26 27 /* 28 * Supported radix tree geometry. 29 * Like p9, we support either 5 or 9 bits at the first (lowest) level, 30 * for a page size of 64k or 4k. 31 */ 32 static int p9_supported_radix_bits[4] = { 5, 9, 9, 13 }; 33 34 unsigned long __kvmhv_copy_tofrom_guest_radix(int lpid, int pid, 35 gva_t eaddr, void *to, void *from, 36 unsigned long n) 37 { 38 int old_pid, old_lpid; 39 unsigned long quadrant, ret = n; 40 bool is_load = !!to; 41 42 /* Can't access quadrants 1 or 2 in non-HV mode, call the HV to do it */ 43 if (kvmhv_on_pseries()) 44 return plpar_hcall_norets(H_COPY_TOFROM_GUEST, lpid, pid, eaddr, 45 (to != NULL) ? __pa(to): 0, 46 (from != NULL) ? __pa(from): 0, n); 47 48 if (eaddr & (0xFFFUL << 52)) 49 return ret; 50 51 quadrant = 1; 52 if (!pid) 53 quadrant = 2; 54 if (is_load) 55 from = (void *) (eaddr | (quadrant << 62)); 56 else 57 to = (void *) (eaddr | (quadrant << 62)); 58 59 preempt_disable(); 60 61 asm volatile("hwsync" ::: "memory"); 62 isync(); 63 /* switch the lpid first to avoid running host with unallocated pid */ 64 old_lpid = mfspr(SPRN_LPID); 65 if (old_lpid != lpid) 66 mtspr(SPRN_LPID, lpid); 67 if (quadrant == 1) { 68 old_pid = mfspr(SPRN_PID); 69 if (old_pid != pid) 70 mtspr(SPRN_PID, pid); 71 } 72 isync(); 73 74 pagefault_disable(); 75 if (is_load) 76 ret = __copy_from_user_inatomic(to, (const void __user *)from, n); 77 else 78 ret = __copy_to_user_inatomic((void __user *)to, from, n); 79 pagefault_enable(); 80 81 asm volatile("hwsync" ::: "memory"); 82 isync(); 83 /* switch the pid first to avoid running host with unallocated pid */ 84 if (quadrant == 1 && pid != old_pid) 85 mtspr(SPRN_PID, old_pid); 86 if (lpid != old_lpid) 87 mtspr(SPRN_LPID, old_lpid); 88 isync(); 89 90 preempt_enable(); 91 92 return ret; 93 } 94 95 static long kvmhv_copy_tofrom_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, 96 void *to, void *from, unsigned long n) 97 { 98 int lpid = vcpu->kvm->arch.lpid; 99 int pid = vcpu->arch.pid; 100 101 /* This would cause a data segment intr so don't allow the access */ 102 if (eaddr & (0x3FFUL << 52)) 103 return -EINVAL; 104 105 /* Should we be using the nested lpid */ 106 if (vcpu->arch.nested) 107 lpid = vcpu->arch.nested->shadow_lpid; 108 109 /* If accessing quadrant 3 then pid is expected to be 0 */ 110 if (((eaddr >> 62) & 0x3) == 0x3) 111 pid = 0; 112 113 eaddr &= ~(0xFFFUL << 52); 114 115 return __kvmhv_copy_tofrom_guest_radix(lpid, pid, eaddr, to, from, n); 116 } 117 118 long kvmhv_copy_from_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, void *to, 119 unsigned long n) 120 { 121 long ret; 122 123 ret = kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, to, NULL, n); 124 if (ret > 0) 125 memset(to + (n - ret), 0, ret); 126 127 return ret; 128 } 129 130 long kvmhv_copy_to_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, void *from, 131 unsigned long n) 132 { 133 return kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, NULL, from, n); 134 } 135 136 int kvmppc_mmu_walk_radix_tree(struct kvm_vcpu *vcpu, gva_t eaddr, 137 struct kvmppc_pte *gpte, u64 root, 138 u64 *pte_ret_p) 139 { 140 struct kvm *kvm = vcpu->kvm; 141 int ret, level, ps; 142 unsigned long rts, bits, offset, index; 143 u64 pte, base, gpa; 144 __be64 rpte; 145 146 rts = ((root & RTS1_MASK) >> (RTS1_SHIFT - 3)) | 147 ((root & RTS2_MASK) >> RTS2_SHIFT); 148 bits = root & RPDS_MASK; 149 base = root & RPDB_MASK; 150 151 offset = rts + 31; 152 153 /* Current implementations only support 52-bit space */ 154 if (offset != 52) 155 return -EINVAL; 156 157 /* Walk each level of the radix tree */ 158 for (level = 3; level >= 0; --level) { 159 u64 addr; 160 /* Check a valid size */ 161 if (level && bits != p9_supported_radix_bits[level]) 162 return -EINVAL; 163 if (level == 0 && !(bits == 5 || bits == 9)) 164 return -EINVAL; 165 offset -= bits; 166 index = (eaddr >> offset) & ((1UL << bits) - 1); 167 /* Check that low bits of page table base are zero */ 168 if (base & ((1UL << (bits + 3)) - 1)) 169 return -EINVAL; 170 /* Read the entry from guest memory */ 171 addr = base + (index * sizeof(rpte)); 172 173 kvm_vcpu_srcu_read_lock(vcpu); 174 ret = kvm_read_guest(kvm, addr, &rpte, sizeof(rpte)); 175 kvm_vcpu_srcu_read_unlock(vcpu); 176 if (ret) { 177 if (pte_ret_p) 178 *pte_ret_p = addr; 179 return ret; 180 } 181 pte = __be64_to_cpu(rpte); 182 if (!(pte & _PAGE_PRESENT)) 183 return -ENOENT; 184 /* Check if a leaf entry */ 185 if (pte & _PAGE_PTE) 186 break; 187 /* Get ready to walk the next level */ 188 base = pte & RPDB_MASK; 189 bits = pte & RPDS_MASK; 190 } 191 192 /* Need a leaf at lowest level; 512GB pages not supported */ 193 if (level < 0 || level == 3) 194 return -EINVAL; 195 196 /* We found a valid leaf PTE */ 197 /* Offset is now log base 2 of the page size */ 198 gpa = pte & 0x01fffffffffff000ul; 199 if (gpa & ((1ul << offset) - 1)) 200 return -EINVAL; 201 gpa |= eaddr & ((1ul << offset) - 1); 202 for (ps = MMU_PAGE_4K; ps < MMU_PAGE_COUNT; ++ps) 203 if (offset == mmu_psize_defs[ps].shift) 204 break; 205 gpte->page_size = ps; 206 gpte->page_shift = offset; 207 208 gpte->eaddr = eaddr; 209 gpte->raddr = gpa; 210 211 /* Work out permissions */ 212 gpte->may_read = !!(pte & _PAGE_READ); 213 gpte->may_write = !!(pte & _PAGE_WRITE); 214 gpte->may_execute = !!(pte & _PAGE_EXEC); 215 216 gpte->rc = pte & (_PAGE_ACCESSED | _PAGE_DIRTY); 217 218 if (pte_ret_p) 219 *pte_ret_p = pte; 220 221 return 0; 222 } 223 224 /* 225 * Used to walk a partition or process table radix tree in guest memory 226 * Note: We exploit the fact that a partition table and a process 227 * table have the same layout, a partition-scoped page table and a 228 * process-scoped page table have the same layout, and the 2nd 229 * doubleword of a partition table entry has the same layout as 230 * the PTCR register. 231 */ 232 int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr, 233 struct kvmppc_pte *gpte, u64 table, 234 int table_index, u64 *pte_ret_p) 235 { 236 struct kvm *kvm = vcpu->kvm; 237 int ret; 238 unsigned long size, ptbl, root; 239 struct prtb_entry entry; 240 241 if ((table & PRTS_MASK) > 24) 242 return -EINVAL; 243 size = 1ul << ((table & PRTS_MASK) + 12); 244 245 /* Is the table big enough to contain this entry? */ 246 if ((table_index * sizeof(entry)) >= size) 247 return -EINVAL; 248 249 /* Read the table to find the root of the radix tree */ 250 ptbl = (table & PRTB_MASK) + (table_index * sizeof(entry)); 251 kvm_vcpu_srcu_read_lock(vcpu); 252 ret = kvm_read_guest(kvm, ptbl, &entry, sizeof(entry)); 253 kvm_vcpu_srcu_read_unlock(vcpu); 254 if (ret) 255 return ret; 256 257 /* Root is stored in the first double word */ 258 root = be64_to_cpu(entry.prtb0); 259 260 return kvmppc_mmu_walk_radix_tree(vcpu, eaddr, gpte, root, pte_ret_p); 261 } 262 263 int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, 264 struct kvmppc_pte *gpte, bool data, bool iswrite) 265 { 266 u32 pid; 267 u64 pte; 268 int ret; 269 270 /* Work out effective PID */ 271 switch (eaddr >> 62) { 272 case 0: 273 pid = vcpu->arch.pid; 274 break; 275 case 3: 276 pid = 0; 277 break; 278 default: 279 return -EINVAL; 280 } 281 282 ret = kvmppc_mmu_radix_translate_table(vcpu, eaddr, gpte, 283 vcpu->kvm->arch.process_table, pid, &pte); 284 if (ret) 285 return ret; 286 287 /* Check privilege (applies only to process scoped translations) */ 288 if (kvmppc_get_msr(vcpu) & MSR_PR) { 289 if (pte & _PAGE_PRIVILEGED) { 290 gpte->may_read = 0; 291 gpte->may_write = 0; 292 gpte->may_execute = 0; 293 } 294 } else { 295 if (!(pte & _PAGE_PRIVILEGED)) { 296 /* Check AMR/IAMR to see if strict mode is in force */ 297 if (vcpu->arch.amr & (1ul << 62)) 298 gpte->may_read = 0; 299 if (vcpu->arch.amr & (1ul << 63)) 300 gpte->may_write = 0; 301 if (vcpu->arch.iamr & (1ul << 62)) 302 gpte->may_execute = 0; 303 } 304 } 305 306 return 0; 307 } 308 309 void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr, 310 unsigned int pshift, unsigned int lpid) 311 { 312 unsigned long psize = PAGE_SIZE; 313 int psi; 314 long rc; 315 unsigned long rb; 316 317 if (pshift) 318 psize = 1UL << pshift; 319 else 320 pshift = PAGE_SHIFT; 321 322 addr &= ~(psize - 1); 323 324 if (!kvmhv_on_pseries()) { 325 radix__flush_tlb_lpid_page(lpid, addr, psize); 326 return; 327 } 328 329 psi = shift_to_mmu_psize(pshift); 330 331 if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE)) { 332 rb = addr | (mmu_get_ap(psi) << PPC_BITLSHIFT(58)); 333 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(0, 0, 1), 334 lpid, rb); 335 } else { 336 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU, 337 H_RPTI_TYPE_NESTED | 338 H_RPTI_TYPE_TLB, 339 psize_to_rpti_pgsize(psi), 340 addr, addr + psize); 341 } 342 343 if (rc) 344 pr_err("KVM: TLB page invalidation hcall failed, rc=%ld\n", rc); 345 } 346 347 static void kvmppc_radix_flush_pwc(struct kvm *kvm, unsigned int lpid) 348 { 349 long rc; 350 351 if (!kvmhv_on_pseries()) { 352 radix__flush_pwc_lpid(lpid); 353 return; 354 } 355 356 if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE)) 357 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(1, 0, 1), 358 lpid, TLBIEL_INVAL_SET_LPID); 359 else 360 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU, 361 H_RPTI_TYPE_NESTED | 362 H_RPTI_TYPE_PWC, H_RPTI_PAGE_ALL, 363 0, -1UL); 364 if (rc) 365 pr_err("KVM: TLB PWC invalidation hcall failed, rc=%ld\n", rc); 366 } 367 368 static unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep, 369 unsigned long clr, unsigned long set, 370 unsigned long addr, unsigned int shift) 371 { 372 return __radix_pte_update(ptep, clr, set); 373 } 374 375 static void kvmppc_radix_set_pte_at(struct kvm *kvm, unsigned long addr, 376 pte_t *ptep, pte_t pte) 377 { 378 radix__set_pte_at(kvm->mm, addr, ptep, pte, 0); 379 } 380 381 static struct kmem_cache *kvm_pte_cache; 382 static struct kmem_cache *kvm_pmd_cache; 383 384 static pte_t *kvmppc_pte_alloc(void) 385 { 386 pte_t *pte; 387 388 pte = kmem_cache_alloc(kvm_pte_cache, GFP_KERNEL); 389 /* pmd_populate() will only reference _pa(pte). */ 390 kmemleak_ignore(pte); 391 392 return pte; 393 } 394 395 static void kvmppc_pte_free(pte_t *ptep) 396 { 397 kmem_cache_free(kvm_pte_cache, ptep); 398 } 399 400 static pmd_t *kvmppc_pmd_alloc(void) 401 { 402 pmd_t *pmd; 403 404 pmd = kmem_cache_alloc(kvm_pmd_cache, GFP_KERNEL); 405 /* pud_populate() will only reference _pa(pmd). */ 406 kmemleak_ignore(pmd); 407 408 return pmd; 409 } 410 411 static void kvmppc_pmd_free(pmd_t *pmdp) 412 { 413 kmem_cache_free(kvm_pmd_cache, pmdp); 414 } 415 416 /* Called with kvm->mmu_lock held */ 417 void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa, 418 unsigned int shift, 419 const struct kvm_memory_slot *memslot, 420 unsigned int lpid) 421 422 { 423 unsigned long old; 424 unsigned long gfn = gpa >> PAGE_SHIFT; 425 unsigned long page_size = PAGE_SIZE; 426 unsigned long hpa; 427 428 old = kvmppc_radix_update_pte(kvm, pte, ~0UL, 0, gpa, shift); 429 kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid); 430 431 /* The following only applies to L1 entries */ 432 if (lpid != kvm->arch.lpid) 433 return; 434 435 if (!memslot) { 436 memslot = gfn_to_memslot(kvm, gfn); 437 if (!memslot) 438 return; 439 } 440 if (shift) { /* 1GB or 2MB page */ 441 page_size = 1ul << shift; 442 if (shift == PMD_SHIFT) 443 kvm->stat.num_2M_pages--; 444 else if (shift == PUD_SHIFT) 445 kvm->stat.num_1G_pages--; 446 } 447 448 gpa &= ~(page_size - 1); 449 hpa = old & PTE_RPN_MASK; 450 kvmhv_remove_nest_rmap_range(kvm, memslot, gpa, hpa, page_size); 451 452 if ((old & _PAGE_DIRTY) && memslot->dirty_bitmap) 453 kvmppc_update_dirty_map(memslot, gfn, page_size); 454 } 455 456 /* 457 * kvmppc_free_p?d are used to free existing page tables, and recursively 458 * descend and clear and free children. 459 * Callers are responsible for flushing the PWC. 460 * 461 * When page tables are being unmapped/freed as part of page fault path 462 * (full == false), valid ptes are generally not expected; however, there 463 * is one situation where they arise, which is when dirty page logging is 464 * turned off for a memslot while the VM is running. The new memslot 465 * becomes visible to page faults before the memslot commit function 466 * gets to flush the memslot, which can lead to a 2MB page mapping being 467 * installed for a guest physical address where there are already 64kB 468 * (or 4kB) mappings (of sub-pages of the same 2MB page). 469 */ 470 static void kvmppc_unmap_free_pte(struct kvm *kvm, pte_t *pte, bool full, 471 unsigned int lpid) 472 { 473 if (full) { 474 memset(pte, 0, sizeof(long) << RADIX_PTE_INDEX_SIZE); 475 } else { 476 pte_t *p = pte; 477 unsigned long it; 478 479 for (it = 0; it < PTRS_PER_PTE; ++it, ++p) { 480 if (pte_val(*p) == 0) 481 continue; 482 kvmppc_unmap_pte(kvm, p, 483 pte_pfn(*p) << PAGE_SHIFT, 484 PAGE_SHIFT, NULL, lpid); 485 } 486 } 487 488 kvmppc_pte_free(pte); 489 } 490 491 static void kvmppc_unmap_free_pmd(struct kvm *kvm, pmd_t *pmd, bool full, 492 unsigned int lpid) 493 { 494 unsigned long im; 495 pmd_t *p = pmd; 496 497 for (im = 0; im < PTRS_PER_PMD; ++im, ++p) { 498 if (!pmd_present(*p)) 499 continue; 500 if (pmd_is_leaf(*p)) { 501 if (full) { 502 pmd_clear(p); 503 } else { 504 WARN_ON_ONCE(1); 505 kvmppc_unmap_pte(kvm, (pte_t *)p, 506 pte_pfn(*(pte_t *)p) << PAGE_SHIFT, 507 PMD_SHIFT, NULL, lpid); 508 } 509 } else { 510 pte_t *pte; 511 512 pte = pte_offset_map(p, 0); 513 kvmppc_unmap_free_pte(kvm, pte, full, lpid); 514 pmd_clear(p); 515 } 516 } 517 kvmppc_pmd_free(pmd); 518 } 519 520 static void kvmppc_unmap_free_pud(struct kvm *kvm, pud_t *pud, 521 unsigned int lpid) 522 { 523 unsigned long iu; 524 pud_t *p = pud; 525 526 for (iu = 0; iu < PTRS_PER_PUD; ++iu, ++p) { 527 if (!pud_present(*p)) 528 continue; 529 if (pud_is_leaf(*p)) { 530 pud_clear(p); 531 } else { 532 pmd_t *pmd; 533 534 pmd = pmd_offset(p, 0); 535 kvmppc_unmap_free_pmd(kvm, pmd, true, lpid); 536 pud_clear(p); 537 } 538 } 539 pud_free(kvm->mm, pud); 540 } 541 542 void kvmppc_free_pgtable_radix(struct kvm *kvm, pgd_t *pgd, unsigned int lpid) 543 { 544 unsigned long ig; 545 546 for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) { 547 p4d_t *p4d = p4d_offset(pgd, 0); 548 pud_t *pud; 549 550 if (!p4d_present(*p4d)) 551 continue; 552 pud = pud_offset(p4d, 0); 553 kvmppc_unmap_free_pud(kvm, pud, lpid); 554 p4d_clear(p4d); 555 } 556 } 557 558 void kvmppc_free_radix(struct kvm *kvm) 559 { 560 if (kvm->arch.pgtable) { 561 kvmppc_free_pgtable_radix(kvm, kvm->arch.pgtable, 562 kvm->arch.lpid); 563 pgd_free(kvm->mm, kvm->arch.pgtable); 564 kvm->arch.pgtable = NULL; 565 } 566 } 567 568 static void kvmppc_unmap_free_pmd_entry_table(struct kvm *kvm, pmd_t *pmd, 569 unsigned long gpa, unsigned int lpid) 570 { 571 pte_t *pte = pte_offset_kernel(pmd, 0); 572 573 /* 574 * Clearing the pmd entry then flushing the PWC ensures that the pte 575 * page no longer be cached by the MMU, so can be freed without 576 * flushing the PWC again. 577 */ 578 pmd_clear(pmd); 579 kvmppc_radix_flush_pwc(kvm, lpid); 580 581 kvmppc_unmap_free_pte(kvm, pte, false, lpid); 582 } 583 584 static void kvmppc_unmap_free_pud_entry_table(struct kvm *kvm, pud_t *pud, 585 unsigned long gpa, unsigned int lpid) 586 { 587 pmd_t *pmd = pmd_offset(pud, 0); 588 589 /* 590 * Clearing the pud entry then flushing the PWC ensures that the pmd 591 * page and any children pte pages will no longer be cached by the MMU, 592 * so can be freed without flushing the PWC again. 593 */ 594 pud_clear(pud); 595 kvmppc_radix_flush_pwc(kvm, lpid); 596 597 kvmppc_unmap_free_pmd(kvm, pmd, false, lpid); 598 } 599 600 /* 601 * There are a number of bits which may differ between different faults to 602 * the same partition scope entry. RC bits, in the course of cleaning and 603 * aging. And the write bit can change, either the access could have been 604 * upgraded, or a read fault could happen concurrently with a write fault 605 * that sets those bits first. 606 */ 607 #define PTE_BITS_MUST_MATCH (~(_PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)) 608 609 int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte, 610 unsigned long gpa, unsigned int level, 611 unsigned long mmu_seq, unsigned int lpid, 612 unsigned long *rmapp, struct rmap_nested **n_rmap) 613 { 614 pgd_t *pgd; 615 p4d_t *p4d; 616 pud_t *pud, *new_pud = NULL; 617 pmd_t *pmd, *new_pmd = NULL; 618 pte_t *ptep, *new_ptep = NULL; 619 int ret; 620 621 /* Traverse the guest's 2nd-level tree, allocate new levels needed */ 622 pgd = pgtable + pgd_index(gpa); 623 p4d = p4d_offset(pgd, gpa); 624 625 pud = NULL; 626 if (p4d_present(*p4d)) 627 pud = pud_offset(p4d, gpa); 628 else 629 new_pud = pud_alloc_one(kvm->mm, gpa); 630 631 pmd = NULL; 632 if (pud && pud_present(*pud) && !pud_is_leaf(*pud)) 633 pmd = pmd_offset(pud, gpa); 634 else if (level <= 1) 635 new_pmd = kvmppc_pmd_alloc(); 636 637 if (level == 0 && !(pmd && pmd_present(*pmd) && !pmd_is_leaf(*pmd))) 638 new_ptep = kvmppc_pte_alloc(); 639 640 /* Check if we might have been invalidated; let the guest retry if so */ 641 spin_lock(&kvm->mmu_lock); 642 ret = -EAGAIN; 643 if (mmu_invalidate_retry(kvm, mmu_seq)) 644 goto out_unlock; 645 646 /* Now traverse again under the lock and change the tree */ 647 ret = -ENOMEM; 648 if (p4d_none(*p4d)) { 649 if (!new_pud) 650 goto out_unlock; 651 p4d_populate(kvm->mm, p4d, new_pud); 652 new_pud = NULL; 653 } 654 pud = pud_offset(p4d, gpa); 655 if (pud_is_leaf(*pud)) { 656 unsigned long hgpa = gpa & PUD_MASK; 657 658 /* Check if we raced and someone else has set the same thing */ 659 if (level == 2) { 660 if (pud_raw(*pud) == pte_raw(pte)) { 661 ret = 0; 662 goto out_unlock; 663 } 664 /* Valid 1GB page here already, add our extra bits */ 665 WARN_ON_ONCE((pud_val(*pud) ^ pte_val(pte)) & 666 PTE_BITS_MUST_MATCH); 667 kvmppc_radix_update_pte(kvm, (pte_t *)pud, 668 0, pte_val(pte), hgpa, PUD_SHIFT); 669 ret = 0; 670 goto out_unlock; 671 } 672 /* 673 * If we raced with another CPU which has just put 674 * a 1GB pte in after we saw a pmd page, try again. 675 */ 676 if (!new_pmd) { 677 ret = -EAGAIN; 678 goto out_unlock; 679 } 680 /* Valid 1GB page here already, remove it */ 681 kvmppc_unmap_pte(kvm, (pte_t *)pud, hgpa, PUD_SHIFT, NULL, 682 lpid); 683 } 684 if (level == 2) { 685 if (!pud_none(*pud)) { 686 /* 687 * There's a page table page here, but we wanted to 688 * install a large page, so remove and free the page 689 * table page. 690 */ 691 kvmppc_unmap_free_pud_entry_table(kvm, pud, gpa, lpid); 692 } 693 kvmppc_radix_set_pte_at(kvm, gpa, (pte_t *)pud, pte); 694 if (rmapp && n_rmap) 695 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap); 696 ret = 0; 697 goto out_unlock; 698 } 699 if (pud_none(*pud)) { 700 if (!new_pmd) 701 goto out_unlock; 702 pud_populate(kvm->mm, pud, new_pmd); 703 new_pmd = NULL; 704 } 705 pmd = pmd_offset(pud, gpa); 706 if (pmd_is_leaf(*pmd)) { 707 unsigned long lgpa = gpa & PMD_MASK; 708 709 /* Check if we raced and someone else has set the same thing */ 710 if (level == 1) { 711 if (pmd_raw(*pmd) == pte_raw(pte)) { 712 ret = 0; 713 goto out_unlock; 714 } 715 /* Valid 2MB page here already, add our extra bits */ 716 WARN_ON_ONCE((pmd_val(*pmd) ^ pte_val(pte)) & 717 PTE_BITS_MUST_MATCH); 718 kvmppc_radix_update_pte(kvm, pmdp_ptep(pmd), 719 0, pte_val(pte), lgpa, PMD_SHIFT); 720 ret = 0; 721 goto out_unlock; 722 } 723 724 /* 725 * If we raced with another CPU which has just put 726 * a 2MB pte in after we saw a pte page, try again. 727 */ 728 if (!new_ptep) { 729 ret = -EAGAIN; 730 goto out_unlock; 731 } 732 /* Valid 2MB page here already, remove it */ 733 kvmppc_unmap_pte(kvm, pmdp_ptep(pmd), lgpa, PMD_SHIFT, NULL, 734 lpid); 735 } 736 if (level == 1) { 737 if (!pmd_none(*pmd)) { 738 /* 739 * There's a page table page here, but we wanted to 740 * install a large page, so remove and free the page 741 * table page. 742 */ 743 kvmppc_unmap_free_pmd_entry_table(kvm, pmd, gpa, lpid); 744 } 745 kvmppc_radix_set_pte_at(kvm, gpa, pmdp_ptep(pmd), pte); 746 if (rmapp && n_rmap) 747 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap); 748 ret = 0; 749 goto out_unlock; 750 } 751 if (pmd_none(*pmd)) { 752 if (!new_ptep) 753 goto out_unlock; 754 pmd_populate(kvm->mm, pmd, new_ptep); 755 new_ptep = NULL; 756 } 757 ptep = pte_offset_kernel(pmd, gpa); 758 if (pte_present(*ptep)) { 759 /* Check if someone else set the same thing */ 760 if (pte_raw(*ptep) == pte_raw(pte)) { 761 ret = 0; 762 goto out_unlock; 763 } 764 /* Valid page here already, add our extra bits */ 765 WARN_ON_ONCE((pte_val(*ptep) ^ pte_val(pte)) & 766 PTE_BITS_MUST_MATCH); 767 kvmppc_radix_update_pte(kvm, ptep, 0, pte_val(pte), gpa, 0); 768 ret = 0; 769 goto out_unlock; 770 } 771 kvmppc_radix_set_pte_at(kvm, gpa, ptep, pte); 772 if (rmapp && n_rmap) 773 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap); 774 ret = 0; 775 776 out_unlock: 777 spin_unlock(&kvm->mmu_lock); 778 if (new_pud) 779 pud_free(kvm->mm, new_pud); 780 if (new_pmd) 781 kvmppc_pmd_free(new_pmd); 782 if (new_ptep) 783 kvmppc_pte_free(new_ptep); 784 return ret; 785 } 786 787 bool kvmppc_hv_handle_set_rc(struct kvm *kvm, bool nested, bool writing, 788 unsigned long gpa, unsigned int lpid) 789 { 790 unsigned long pgflags; 791 unsigned int shift; 792 pte_t *ptep; 793 794 /* 795 * Need to set an R or C bit in the 2nd-level tables; 796 * since we are just helping out the hardware here, 797 * it is sufficient to do what the hardware does. 798 */ 799 pgflags = _PAGE_ACCESSED; 800 if (writing) 801 pgflags |= _PAGE_DIRTY; 802 803 if (nested) 804 ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift); 805 else 806 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 807 808 if (ptep && pte_present(*ptep) && (!writing || pte_write(*ptep))) { 809 kvmppc_radix_update_pte(kvm, ptep, 0, pgflags, gpa, shift); 810 return true; 811 } 812 return false; 813 } 814 815 int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu, 816 unsigned long gpa, 817 struct kvm_memory_slot *memslot, 818 bool writing, bool kvm_ro, 819 pte_t *inserted_pte, unsigned int *levelp) 820 { 821 struct kvm *kvm = vcpu->kvm; 822 struct page *page = NULL; 823 unsigned long mmu_seq; 824 unsigned long hva, gfn = gpa >> PAGE_SHIFT; 825 bool upgrade_write = false; 826 bool *upgrade_p = &upgrade_write; 827 pte_t pte, *ptep; 828 unsigned int shift, level; 829 int ret; 830 bool large_enable; 831 832 /* used to check for invalidations in progress */ 833 mmu_seq = kvm->mmu_invalidate_seq; 834 smp_rmb(); 835 836 /* 837 * Do a fast check first, since __gfn_to_pfn_memslot doesn't 838 * do it with !atomic && !async, which is how we call it. 839 * We always ask for write permission since the common case 840 * is that the page is writable. 841 */ 842 hva = gfn_to_hva_memslot(memslot, gfn); 843 if (!kvm_ro && get_user_page_fast_only(hva, FOLL_WRITE, &page)) { 844 upgrade_write = true; 845 } else { 846 unsigned long pfn; 847 848 /* Call KVM generic code to do the slow-path check */ 849 pfn = __gfn_to_pfn_memslot(memslot, gfn, false, false, NULL, 850 writing, upgrade_p, NULL); 851 if (is_error_noslot_pfn(pfn)) 852 return -EFAULT; 853 page = NULL; 854 if (pfn_valid(pfn)) { 855 page = pfn_to_page(pfn); 856 if (PageReserved(page)) 857 page = NULL; 858 } 859 } 860 861 /* 862 * Read the PTE from the process' radix tree and use that 863 * so we get the shift and attribute bits. 864 */ 865 spin_lock(&kvm->mmu_lock); 866 ptep = find_kvm_host_pte(kvm, mmu_seq, hva, &shift); 867 pte = __pte(0); 868 if (ptep) 869 pte = READ_ONCE(*ptep); 870 spin_unlock(&kvm->mmu_lock); 871 /* 872 * If the PTE disappeared temporarily due to a THP 873 * collapse, just return and let the guest try again. 874 */ 875 if (!pte_present(pte)) { 876 if (page) 877 put_page(page); 878 return RESUME_GUEST; 879 } 880 881 /* If we're logging dirty pages, always map single pages */ 882 large_enable = !(memslot->flags & KVM_MEM_LOG_DIRTY_PAGES); 883 884 /* Get pte level from shift/size */ 885 if (large_enable && shift == PUD_SHIFT && 886 (gpa & (PUD_SIZE - PAGE_SIZE)) == 887 (hva & (PUD_SIZE - PAGE_SIZE))) { 888 level = 2; 889 } else if (large_enable && shift == PMD_SHIFT && 890 (gpa & (PMD_SIZE - PAGE_SIZE)) == 891 (hva & (PMD_SIZE - PAGE_SIZE))) { 892 level = 1; 893 } else { 894 level = 0; 895 if (shift > PAGE_SHIFT) { 896 /* 897 * If the pte maps more than one page, bring over 898 * bits from the virtual address to get the real 899 * address of the specific single page we want. 900 */ 901 unsigned long rpnmask = (1ul << shift) - PAGE_SIZE; 902 pte = __pte(pte_val(pte) | (hva & rpnmask)); 903 } 904 } 905 906 pte = __pte(pte_val(pte) | _PAGE_EXEC | _PAGE_ACCESSED); 907 if (writing || upgrade_write) { 908 if (pte_val(pte) & _PAGE_WRITE) 909 pte = __pte(pte_val(pte) | _PAGE_DIRTY); 910 } else { 911 pte = __pte(pte_val(pte) & ~(_PAGE_WRITE | _PAGE_DIRTY)); 912 } 913 914 /* Allocate space in the tree and write the PTE */ 915 ret = kvmppc_create_pte(kvm, kvm->arch.pgtable, pte, gpa, level, 916 mmu_seq, kvm->arch.lpid, NULL, NULL); 917 if (inserted_pte) 918 *inserted_pte = pte; 919 if (levelp) 920 *levelp = level; 921 922 if (page) { 923 if (!ret && (pte_val(pte) & _PAGE_WRITE)) 924 set_page_dirty_lock(page); 925 put_page(page); 926 } 927 928 /* Increment number of large pages if we (successfully) inserted one */ 929 if (!ret) { 930 if (level == 1) 931 kvm->stat.num_2M_pages++; 932 else if (level == 2) 933 kvm->stat.num_1G_pages++; 934 } 935 936 return ret; 937 } 938 939 int kvmppc_book3s_radix_page_fault(struct kvm_vcpu *vcpu, 940 unsigned long ea, unsigned long dsisr) 941 { 942 struct kvm *kvm = vcpu->kvm; 943 unsigned long gpa, gfn; 944 struct kvm_memory_slot *memslot; 945 long ret; 946 bool writing = !!(dsisr & DSISR_ISSTORE); 947 bool kvm_ro = false; 948 949 /* Check for unusual errors */ 950 if (dsisr & DSISR_UNSUPP_MMU) { 951 pr_err("KVM: Got unsupported MMU fault\n"); 952 return -EFAULT; 953 } 954 if (dsisr & DSISR_BADACCESS) { 955 /* Reflect to the guest as DSI */ 956 pr_err("KVM: Got radix HV page fault with DSISR=%lx\n", dsisr); 957 kvmppc_core_queue_data_storage(vcpu, 958 kvmppc_get_msr(vcpu) & SRR1_PREFIXED, 959 ea, dsisr); 960 return RESUME_GUEST; 961 } 962 963 /* Translate the logical address */ 964 gpa = vcpu->arch.fault_gpa & ~0xfffUL; 965 gpa &= ~0xF000000000000000ul; 966 gfn = gpa >> PAGE_SHIFT; 967 if (!(dsisr & DSISR_PRTABLE_FAULT)) 968 gpa |= ea & 0xfff; 969 970 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 971 return kvmppc_send_page_to_uv(kvm, gfn); 972 973 /* Get the corresponding memslot */ 974 memslot = gfn_to_memslot(kvm, gfn); 975 976 /* No memslot means it's an emulated MMIO region */ 977 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) { 978 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS | 979 DSISR_SET_RC)) { 980 /* 981 * Bad address in guest page table tree, or other 982 * unusual error - reflect it to the guest as DSI. 983 */ 984 kvmppc_core_queue_data_storage(vcpu, 985 kvmppc_get_msr(vcpu) & SRR1_PREFIXED, 986 ea, dsisr); 987 return RESUME_GUEST; 988 } 989 return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing); 990 } 991 992 if (memslot->flags & KVM_MEM_READONLY) { 993 if (writing) { 994 /* give the guest a DSI */ 995 kvmppc_core_queue_data_storage(vcpu, 996 kvmppc_get_msr(vcpu) & SRR1_PREFIXED, 997 ea, DSISR_ISSTORE | DSISR_PROTFAULT); 998 return RESUME_GUEST; 999 } 1000 kvm_ro = true; 1001 } 1002 1003 /* Failed to set the reference/change bits */ 1004 if (dsisr & DSISR_SET_RC) { 1005 spin_lock(&kvm->mmu_lock); 1006 if (kvmppc_hv_handle_set_rc(kvm, false, writing, 1007 gpa, kvm->arch.lpid)) 1008 dsisr &= ~DSISR_SET_RC; 1009 spin_unlock(&kvm->mmu_lock); 1010 1011 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE | 1012 DSISR_PROTFAULT | DSISR_SET_RC))) 1013 return RESUME_GUEST; 1014 } 1015 1016 /* Try to insert a pte */ 1017 ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot, writing, 1018 kvm_ro, NULL, NULL); 1019 1020 if (ret == 0 || ret == -EAGAIN) 1021 ret = RESUME_GUEST; 1022 return ret; 1023 } 1024 1025 /* Called with kvm->mmu_lock held */ 1026 void kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, 1027 unsigned long gfn) 1028 { 1029 pte_t *ptep; 1030 unsigned long gpa = gfn << PAGE_SHIFT; 1031 unsigned int shift; 1032 1033 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) { 1034 uv_page_inval(kvm->arch.lpid, gpa, PAGE_SHIFT); 1035 return; 1036 } 1037 1038 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1039 if (ptep && pte_present(*ptep)) 1040 kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot, 1041 kvm->arch.lpid); 1042 } 1043 1044 /* Called with kvm->mmu_lock held */ 1045 bool kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, 1046 unsigned long gfn) 1047 { 1048 pte_t *ptep; 1049 unsigned long gpa = gfn << PAGE_SHIFT; 1050 unsigned int shift; 1051 bool ref = false; 1052 unsigned long old, *rmapp; 1053 1054 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1055 return ref; 1056 1057 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1058 if (ptep && pte_present(*ptep) && pte_young(*ptep)) { 1059 old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_ACCESSED, 0, 1060 gpa, shift); 1061 /* XXX need to flush tlb here? */ 1062 /* Also clear bit in ptes in shadow pgtable for nested guests */ 1063 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 1064 kvmhv_update_nest_rmap_rc_list(kvm, rmapp, _PAGE_ACCESSED, 0, 1065 old & PTE_RPN_MASK, 1066 1UL << shift); 1067 ref = true; 1068 } 1069 return ref; 1070 } 1071 1072 /* Called with kvm->mmu_lock held */ 1073 bool kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, 1074 unsigned long gfn) 1075 1076 { 1077 pte_t *ptep; 1078 unsigned long gpa = gfn << PAGE_SHIFT; 1079 unsigned int shift; 1080 bool ref = false; 1081 1082 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1083 return ref; 1084 1085 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1086 if (ptep && pte_present(*ptep) && pte_young(*ptep)) 1087 ref = true; 1088 return ref; 1089 } 1090 1091 /* Returns the number of PAGE_SIZE pages that are dirty */ 1092 static int kvm_radix_test_clear_dirty(struct kvm *kvm, 1093 struct kvm_memory_slot *memslot, int pagenum) 1094 { 1095 unsigned long gfn = memslot->base_gfn + pagenum; 1096 unsigned long gpa = gfn << PAGE_SHIFT; 1097 pte_t *ptep, pte; 1098 unsigned int shift; 1099 int ret = 0; 1100 unsigned long old, *rmapp; 1101 1102 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1103 return ret; 1104 1105 /* 1106 * For performance reasons we don't hold kvm->mmu_lock while walking the 1107 * partition scoped table. 1108 */ 1109 ptep = find_kvm_secondary_pte_unlocked(kvm, gpa, &shift); 1110 if (!ptep) 1111 return 0; 1112 1113 pte = READ_ONCE(*ptep); 1114 if (pte_present(pte) && pte_dirty(pte)) { 1115 spin_lock(&kvm->mmu_lock); 1116 /* 1117 * Recheck the pte again 1118 */ 1119 if (pte_val(pte) != pte_val(*ptep)) { 1120 /* 1121 * We have KVM_MEM_LOG_DIRTY_PAGES enabled. Hence we can 1122 * only find PAGE_SIZE pte entries here. We can continue 1123 * to use the pte addr returned by above page table 1124 * walk. 1125 */ 1126 if (!pte_present(*ptep) || !pte_dirty(*ptep)) { 1127 spin_unlock(&kvm->mmu_lock); 1128 return 0; 1129 } 1130 } 1131 1132 ret = 1; 1133 VM_BUG_ON(shift); 1134 old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_DIRTY, 0, 1135 gpa, shift); 1136 kvmppc_radix_tlbie_page(kvm, gpa, shift, kvm->arch.lpid); 1137 /* Also clear bit in ptes in shadow pgtable for nested guests */ 1138 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 1139 kvmhv_update_nest_rmap_rc_list(kvm, rmapp, _PAGE_DIRTY, 0, 1140 old & PTE_RPN_MASK, 1141 1UL << shift); 1142 spin_unlock(&kvm->mmu_lock); 1143 } 1144 return ret; 1145 } 1146 1147 long kvmppc_hv_get_dirty_log_radix(struct kvm *kvm, 1148 struct kvm_memory_slot *memslot, unsigned long *map) 1149 { 1150 unsigned long i, j; 1151 int npages; 1152 1153 for (i = 0; i < memslot->npages; i = j) { 1154 npages = kvm_radix_test_clear_dirty(kvm, memslot, i); 1155 1156 /* 1157 * Note that if npages > 0 then i must be a multiple of npages, 1158 * since huge pages are only used to back the guest at guest 1159 * real addresses that are a multiple of their size. 1160 * Since we have at most one PTE covering any given guest 1161 * real address, if npages > 1 we can skip to i + npages. 1162 */ 1163 j = i + 1; 1164 if (npages) { 1165 set_dirty_bits(map, i, npages); 1166 j = i + npages; 1167 } 1168 } 1169 return 0; 1170 } 1171 1172 void kvmppc_radix_flush_memslot(struct kvm *kvm, 1173 const struct kvm_memory_slot *memslot) 1174 { 1175 unsigned long n; 1176 pte_t *ptep; 1177 unsigned long gpa; 1178 unsigned int shift; 1179 1180 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_START) 1181 kvmppc_uvmem_drop_pages(memslot, kvm, true); 1182 1183 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1184 return; 1185 1186 gpa = memslot->base_gfn << PAGE_SHIFT; 1187 spin_lock(&kvm->mmu_lock); 1188 for (n = memslot->npages; n; --n) { 1189 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1190 if (ptep && pte_present(*ptep)) 1191 kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot, 1192 kvm->arch.lpid); 1193 gpa += PAGE_SIZE; 1194 } 1195 /* 1196 * Increase the mmu notifier sequence number to prevent any page 1197 * fault that read the memslot earlier from writing a PTE. 1198 */ 1199 kvm->mmu_invalidate_seq++; 1200 spin_unlock(&kvm->mmu_lock); 1201 } 1202 1203 static void add_rmmu_ap_encoding(struct kvm_ppc_rmmu_info *info, 1204 int psize, int *indexp) 1205 { 1206 if (!mmu_psize_defs[psize].shift) 1207 return; 1208 info->ap_encodings[*indexp] = mmu_psize_defs[psize].shift | 1209 (mmu_psize_defs[psize].ap << 29); 1210 ++(*indexp); 1211 } 1212 1213 int kvmhv_get_rmmu_info(struct kvm *kvm, struct kvm_ppc_rmmu_info *info) 1214 { 1215 int i; 1216 1217 if (!radix_enabled()) 1218 return -EINVAL; 1219 memset(info, 0, sizeof(*info)); 1220 1221 /* 4k page size */ 1222 info->geometries[0].page_shift = 12; 1223 info->geometries[0].level_bits[0] = 9; 1224 for (i = 1; i < 4; ++i) 1225 info->geometries[0].level_bits[i] = p9_supported_radix_bits[i]; 1226 /* 64k page size */ 1227 info->geometries[1].page_shift = 16; 1228 for (i = 0; i < 4; ++i) 1229 info->geometries[1].level_bits[i] = p9_supported_radix_bits[i]; 1230 1231 i = 0; 1232 add_rmmu_ap_encoding(info, MMU_PAGE_4K, &i); 1233 add_rmmu_ap_encoding(info, MMU_PAGE_64K, &i); 1234 add_rmmu_ap_encoding(info, MMU_PAGE_2M, &i); 1235 add_rmmu_ap_encoding(info, MMU_PAGE_1G, &i); 1236 1237 return 0; 1238 } 1239 1240 int kvmppc_init_vm_radix(struct kvm *kvm) 1241 { 1242 kvm->arch.pgtable = pgd_alloc(kvm->mm); 1243 if (!kvm->arch.pgtable) 1244 return -ENOMEM; 1245 return 0; 1246 } 1247 1248 static void pte_ctor(void *addr) 1249 { 1250 memset(addr, 0, RADIX_PTE_TABLE_SIZE); 1251 } 1252 1253 static void pmd_ctor(void *addr) 1254 { 1255 memset(addr, 0, RADIX_PMD_TABLE_SIZE); 1256 } 1257 1258 struct debugfs_radix_state { 1259 struct kvm *kvm; 1260 struct mutex mutex; 1261 unsigned long gpa; 1262 int lpid; 1263 int chars_left; 1264 int buf_index; 1265 char buf[128]; 1266 u8 hdr; 1267 }; 1268 1269 static int debugfs_radix_open(struct inode *inode, struct file *file) 1270 { 1271 struct kvm *kvm = inode->i_private; 1272 struct debugfs_radix_state *p; 1273 1274 p = kzalloc(sizeof(*p), GFP_KERNEL); 1275 if (!p) 1276 return -ENOMEM; 1277 1278 kvm_get_kvm(kvm); 1279 p->kvm = kvm; 1280 mutex_init(&p->mutex); 1281 file->private_data = p; 1282 1283 return nonseekable_open(inode, file); 1284 } 1285 1286 static int debugfs_radix_release(struct inode *inode, struct file *file) 1287 { 1288 struct debugfs_radix_state *p = file->private_data; 1289 1290 kvm_put_kvm(p->kvm); 1291 kfree(p); 1292 return 0; 1293 } 1294 1295 static ssize_t debugfs_radix_read(struct file *file, char __user *buf, 1296 size_t len, loff_t *ppos) 1297 { 1298 struct debugfs_radix_state *p = file->private_data; 1299 ssize_t ret, r; 1300 unsigned long n; 1301 struct kvm *kvm; 1302 unsigned long gpa; 1303 pgd_t *pgt; 1304 struct kvm_nested_guest *nested; 1305 pgd_t *pgdp; 1306 p4d_t p4d, *p4dp; 1307 pud_t pud, *pudp; 1308 pmd_t pmd, *pmdp; 1309 pte_t *ptep; 1310 int shift; 1311 unsigned long pte; 1312 1313 kvm = p->kvm; 1314 if (!kvm_is_radix(kvm)) 1315 return 0; 1316 1317 ret = mutex_lock_interruptible(&p->mutex); 1318 if (ret) 1319 return ret; 1320 1321 if (p->chars_left) { 1322 n = p->chars_left; 1323 if (n > len) 1324 n = len; 1325 r = copy_to_user(buf, p->buf + p->buf_index, n); 1326 n -= r; 1327 p->chars_left -= n; 1328 p->buf_index += n; 1329 buf += n; 1330 len -= n; 1331 ret = n; 1332 if (r) { 1333 if (!n) 1334 ret = -EFAULT; 1335 goto out; 1336 } 1337 } 1338 1339 gpa = p->gpa; 1340 nested = NULL; 1341 pgt = NULL; 1342 while (len != 0 && p->lpid >= 0) { 1343 if (gpa >= RADIX_PGTABLE_RANGE) { 1344 gpa = 0; 1345 pgt = NULL; 1346 if (nested) { 1347 kvmhv_put_nested(nested); 1348 nested = NULL; 1349 } 1350 p->lpid = kvmhv_nested_next_lpid(kvm, p->lpid); 1351 p->hdr = 0; 1352 if (p->lpid < 0) 1353 break; 1354 } 1355 if (!pgt) { 1356 if (p->lpid == 0) { 1357 pgt = kvm->arch.pgtable; 1358 } else { 1359 nested = kvmhv_get_nested(kvm, p->lpid, false); 1360 if (!nested) { 1361 gpa = RADIX_PGTABLE_RANGE; 1362 continue; 1363 } 1364 pgt = nested->shadow_pgtable; 1365 } 1366 } 1367 n = 0; 1368 if (!p->hdr) { 1369 if (p->lpid > 0) 1370 n = scnprintf(p->buf, sizeof(p->buf), 1371 "\nNested LPID %d: ", p->lpid); 1372 n += scnprintf(p->buf + n, sizeof(p->buf) - n, 1373 "pgdir: %lx\n", (unsigned long)pgt); 1374 p->hdr = 1; 1375 goto copy; 1376 } 1377 1378 pgdp = pgt + pgd_index(gpa); 1379 p4dp = p4d_offset(pgdp, gpa); 1380 p4d = READ_ONCE(*p4dp); 1381 if (!(p4d_val(p4d) & _PAGE_PRESENT)) { 1382 gpa = (gpa & P4D_MASK) + P4D_SIZE; 1383 continue; 1384 } 1385 1386 pudp = pud_offset(&p4d, gpa); 1387 pud = READ_ONCE(*pudp); 1388 if (!(pud_val(pud) & _PAGE_PRESENT)) { 1389 gpa = (gpa & PUD_MASK) + PUD_SIZE; 1390 continue; 1391 } 1392 if (pud_val(pud) & _PAGE_PTE) { 1393 pte = pud_val(pud); 1394 shift = PUD_SHIFT; 1395 goto leaf; 1396 } 1397 1398 pmdp = pmd_offset(&pud, gpa); 1399 pmd = READ_ONCE(*pmdp); 1400 if (!(pmd_val(pmd) & _PAGE_PRESENT)) { 1401 gpa = (gpa & PMD_MASK) + PMD_SIZE; 1402 continue; 1403 } 1404 if (pmd_val(pmd) & _PAGE_PTE) { 1405 pte = pmd_val(pmd); 1406 shift = PMD_SHIFT; 1407 goto leaf; 1408 } 1409 1410 ptep = pte_offset_kernel(&pmd, gpa); 1411 pte = pte_val(READ_ONCE(*ptep)); 1412 if (!(pte & _PAGE_PRESENT)) { 1413 gpa += PAGE_SIZE; 1414 continue; 1415 } 1416 shift = PAGE_SHIFT; 1417 leaf: 1418 n = scnprintf(p->buf, sizeof(p->buf), 1419 " %lx: %lx %d\n", gpa, pte, shift); 1420 gpa += 1ul << shift; 1421 copy: 1422 p->chars_left = n; 1423 if (n > len) 1424 n = len; 1425 r = copy_to_user(buf, p->buf, n); 1426 n -= r; 1427 p->chars_left -= n; 1428 p->buf_index = n; 1429 buf += n; 1430 len -= n; 1431 ret += n; 1432 if (r) { 1433 if (!ret) 1434 ret = -EFAULT; 1435 break; 1436 } 1437 } 1438 p->gpa = gpa; 1439 if (nested) 1440 kvmhv_put_nested(nested); 1441 1442 out: 1443 mutex_unlock(&p->mutex); 1444 return ret; 1445 } 1446 1447 static ssize_t debugfs_radix_write(struct file *file, const char __user *buf, 1448 size_t len, loff_t *ppos) 1449 { 1450 return -EACCES; 1451 } 1452 1453 static const struct file_operations debugfs_radix_fops = { 1454 .owner = THIS_MODULE, 1455 .open = debugfs_radix_open, 1456 .release = debugfs_radix_release, 1457 .read = debugfs_radix_read, 1458 .write = debugfs_radix_write, 1459 .llseek = generic_file_llseek, 1460 }; 1461 1462 void kvmhv_radix_debugfs_init(struct kvm *kvm) 1463 { 1464 debugfs_create_file("radix", 0400, kvm->debugfs_dentry, kvm, 1465 &debugfs_radix_fops); 1466 } 1467 1468 int kvmppc_radix_init(void) 1469 { 1470 unsigned long size = sizeof(void *) << RADIX_PTE_INDEX_SIZE; 1471 1472 kvm_pte_cache = kmem_cache_create("kvm-pte", size, size, 0, pte_ctor); 1473 if (!kvm_pte_cache) 1474 return -ENOMEM; 1475 1476 size = sizeof(void *) << RADIX_PMD_INDEX_SIZE; 1477 1478 kvm_pmd_cache = kmem_cache_create("kvm-pmd", size, size, 0, pmd_ctor); 1479 if (!kvm_pmd_cache) { 1480 kmem_cache_destroy(kvm_pte_cache); 1481 return -ENOMEM; 1482 } 1483 1484 return 0; 1485 } 1486 1487 void kvmppc_radix_exit(void) 1488 { 1489 kmem_cache_destroy(kvm_pte_cache); 1490 kmem_cache_destroy(kvm_pmd_cache); 1491 } 1492