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 "book3s_hv.h" 19#include <asm/page.h> 20#include <asm/mmu.h> 21#include <asm/pgalloc.h> 22#include <asm/pte-walk.h> 23#include <asm/ultravisor.h> 24#include <asm/kvm_book3s_uvmem.h> 25#include <asm/plpar_wrappers.h> 26#include <asm/firmware.h> 27 28/* 29 * Supported radix tree geometry. 30 * Like p9, we support either 5 or 9 bits at the first (lowest) level, 31 * for a page size of 64k or 4k. 32 */ 33static int p9_supported_radix_bits[4] = { 5, 9, 9, 13 }; 34 35unsigned long __kvmhv_copy_tofrom_guest_radix(int lpid, int pid, 36 gva_t eaddr, void *to, void *from, 37 unsigned long n) 38{ 39 int old_pid, old_lpid; 40 unsigned long quadrant, ret = n; 41 bool is_load = !!to; 42 43 if (kvmhv_is_nestedv2()) 44 return H_UNSUPPORTED; 45 46 /* Can't access quadrants 1 or 2 in non-HV mode, call the HV to do it */ 47 if (kvmhv_on_pseries()) 48 return plpar_hcall_norets(H_COPY_TOFROM_GUEST, lpid, pid, eaddr, 49 (to != NULL) ? __pa(to): 0, 50 (from != NULL) ? __pa(from): 0, n); 51 52 if (eaddr & (0xFFFUL << 52)) 53 return ret; 54 55 quadrant = 1; 56 if (!pid) 57 quadrant = 2; 58 if (is_load) 59 from = (void *) (eaddr | (quadrant << 62)); 60 else 61 to = (void *) (eaddr | (quadrant << 62)); 62 63 preempt_disable(); 64 65 asm volatile("hwsync" ::: "memory"); 66 isync(); 67 /* switch the lpid first to avoid running host with unallocated pid */ 68 old_lpid = mfspr(SPRN_LPID); 69 if (old_lpid != lpid) 70 mtspr(SPRN_LPID, lpid); 71 if (quadrant == 1) { 72 old_pid = mfspr(SPRN_PID); 73 if (old_pid != pid) 74 mtspr(SPRN_PID, pid); 75 } 76 isync(); 77 78 pagefault_disable(); 79 if (is_load) 80 ret = __copy_from_user_inatomic(to, (const void __user *)from, n); 81 else 82 ret = __copy_to_user_inatomic((void __user *)to, from, n); 83 pagefault_enable(); 84 85 asm volatile("hwsync" ::: "memory"); 86 isync(); 87 /* switch the pid first to avoid running host with unallocated pid */ 88 if (quadrant == 1 && pid != old_pid) 89 mtspr(SPRN_PID, old_pid); 90 if (lpid != old_lpid) 91 mtspr(SPRN_LPID, old_lpid); 92 isync(); 93 94 preempt_enable(); 95 96 return ret; 97} 98 99static long kvmhv_copy_tofrom_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, 100 void *to, void *from, unsigned long n) 101{ 102 int lpid = vcpu->kvm->arch.lpid; 103 int pid; 104 105 /* This would cause a data segment intr so don't allow the access */ 106 if (eaddr & (0x3FFUL << 52)) 107 return -EINVAL; 108 109 /* Should we be using the nested lpid */ 110 if (vcpu->arch.nested) 111 lpid = vcpu->arch.nested->shadow_lpid; 112 113 /* If accessing quadrant 3 then pid is expected to be 0 */ 114 if (((eaddr >> 62) & 0x3) == 0x3) 115 pid = 0; 116 else 117 pid = kvmppc_get_pid(vcpu); 118 119 eaddr &= ~(0xFFFUL << 52); 120 121 return __kvmhv_copy_tofrom_guest_radix(lpid, pid, eaddr, to, from, n); 122} 123 124long kvmhv_copy_from_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, void *to, 125 unsigned long n) 126{ 127 long ret; 128 129 ret = kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, to, NULL, n); 130 if (ret > 0) 131 memset(to + (n - ret), 0, ret); 132 133 return ret; 134} 135 136long kvmhv_copy_to_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, void *from, 137 unsigned long n) 138{ 139 return kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, NULL, from, n); 140} 141 142int kvmppc_mmu_walk_radix_tree(struct kvm_vcpu *vcpu, gva_t eaddr, 143 struct kvmppc_pte *gpte, u64 root, 144 u64 *pte_ret_p) 145{ 146 struct kvm *kvm = vcpu->kvm; 147 int ret, level, ps; 148 unsigned long rts, bits, offset, index; 149 u64 pte, base, gpa; 150 __be64 rpte; 151 152 rts = ((root & RTS1_MASK) >> (RTS1_SHIFT - 3)) | 153 ((root & RTS2_MASK) >> RTS2_SHIFT); 154 bits = root & RPDS_MASK; 155 base = root & RPDB_MASK; 156 157 offset = rts + 31; 158 159 /* Current implementations only support 52-bit space */ 160 if (offset != 52) 161 return -EINVAL; 162 163 /* Walk each level of the radix tree */ 164 for (level = 3; level >= 0; --level) { 165 u64 addr; 166 /* Check a valid size */ 167 if (level && bits != p9_supported_radix_bits[level]) 168 return -EINVAL; 169 if (level == 0 && !(bits == 5 || bits == 9)) 170 return -EINVAL; 171 offset -= bits; 172 index = (eaddr >> offset) & ((1UL << bits) - 1); 173 /* Check that low bits of page table base are zero */ 174 if (base & ((1UL << (bits + 3)) - 1)) 175 return -EINVAL; 176 /* Read the entry from guest memory */ 177 addr = base + (index * sizeof(rpte)); 178 179 kvm_vcpu_srcu_read_lock(vcpu); 180 ret = kvm_read_guest(kvm, addr, &rpte, sizeof(rpte)); 181 kvm_vcpu_srcu_read_unlock(vcpu); 182 if (ret) { 183 if (pte_ret_p) 184 *pte_ret_p = addr; 185 return ret; 186 } 187 pte = __be64_to_cpu(rpte); 188 if (!(pte & _PAGE_PRESENT)) 189 return -ENOENT; 190 /* Check if a leaf entry */ 191 if (pte & _PAGE_PTE) 192 break; 193 /* Get ready to walk the next level */ 194 base = pte & RPDB_MASK; 195 bits = pte & RPDS_MASK; 196 } 197 198 /* Need a leaf at lowest level; 512GB pages not supported */ 199 if (level < 0 || level == 3) 200 return -EINVAL; 201 202 /* We found a valid leaf PTE */ 203 /* Offset is now log base 2 of the page size */ 204 gpa = pte & 0x01fffffffffff000ul; 205 if (gpa & ((1ul << offset) - 1)) 206 return -EINVAL; 207 gpa |= eaddr & ((1ul << offset) - 1); 208 for (ps = MMU_PAGE_4K; ps < MMU_PAGE_COUNT; ++ps) 209 if (offset == mmu_psize_defs[ps].shift) 210 break; 211 gpte->page_size = ps; 212 gpte->page_shift = offset; 213 214 gpte->eaddr = eaddr; 215 gpte->raddr = gpa; 216 217 /* Work out permissions */ 218 gpte->may_read = !!(pte & _PAGE_READ); 219 gpte->may_write = !!(pte & _PAGE_WRITE); 220 gpte->may_execute = !!(pte & _PAGE_EXEC); 221 222 gpte->rc = pte & (_PAGE_ACCESSED | _PAGE_DIRTY); 223 224 if (pte_ret_p) 225 *pte_ret_p = pte; 226 227 return 0; 228} 229 230/* 231 * Used to walk a partition or process table radix tree in guest memory 232 * Note: We exploit the fact that a partition table and a process 233 * table have the same layout, a partition-scoped page table and a 234 * process-scoped page table have the same layout, and the 2nd 235 * doubleword of a partition table entry has the same layout as 236 * the PTCR register. 237 */ 238int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr, 239 struct kvmppc_pte *gpte, u64 table, 240 int table_index, u64 *pte_ret_p) 241{ 242 struct kvm *kvm = vcpu->kvm; 243 int ret; 244 unsigned long size, ptbl, root; 245 struct prtb_entry entry; 246 247 if ((table & PRTS_MASK) > 24) 248 return -EINVAL; 249 size = 1ul << ((table & PRTS_MASK) + 12); 250 251 /* Is the table big enough to contain this entry? */ 252 if ((table_index * sizeof(entry)) >= size) 253 return -EINVAL; 254 255 /* Read the table to find the root of the radix tree */ 256 ptbl = (table & PRTB_MASK) + (table_index * sizeof(entry)); 257 kvm_vcpu_srcu_read_lock(vcpu); 258 ret = kvm_read_guest(kvm, ptbl, &entry, sizeof(entry)); 259 kvm_vcpu_srcu_read_unlock(vcpu); 260 if (ret) 261 return ret; 262 263 /* Root is stored in the first double word */ 264 root = be64_to_cpu(entry.prtb0); 265 266 return kvmppc_mmu_walk_radix_tree(vcpu, eaddr, gpte, root, pte_ret_p); 267} 268 269int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, 270 struct kvmppc_pte *gpte, bool data, bool iswrite) 271{ 272 u32 pid; 273 u64 pte; 274 int ret; 275 276 /* Work out effective PID */ 277 switch (eaddr >> 62) { 278 case 0: 279 pid = kvmppc_get_pid(vcpu); 280 break; 281 case 3: 282 pid = 0; 283 break; 284 default: 285 return -EINVAL; 286 } 287 288 ret = kvmppc_mmu_radix_translate_table(vcpu, eaddr, gpte, 289 vcpu->kvm->arch.process_table, pid, &pte); 290 if (ret) 291 return ret; 292 293 /* Check privilege (applies only to process scoped translations) */ 294 if (kvmppc_get_msr(vcpu) & MSR_PR) { 295 if (pte & _PAGE_PRIVILEGED) { 296 gpte->may_read = 0; 297 gpte->may_write = 0; 298 gpte->may_execute = 0; 299 } 300 } else { 301 if (!(pte & _PAGE_PRIVILEGED)) { 302 /* Check AMR/IAMR to see if strict mode is in force */ 303 if (kvmppc_get_amr_hv(vcpu) & (1ul << 62)) 304 gpte->may_read = 0; 305 if (kvmppc_get_amr_hv(vcpu) & (1ul << 63)) 306 gpte->may_write = 0; 307 if (vcpu->arch.iamr & (1ul << 62)) 308 gpte->may_execute = 0; 309 } 310 } 311 312 return 0; 313} 314 315void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr, 316 unsigned int pshift, u64 lpid) 317{ 318 unsigned long psize = PAGE_SIZE; 319 int psi; 320 long rc; 321 unsigned long rb; 322 323 if (pshift) 324 psize = 1UL << pshift; 325 else 326 pshift = PAGE_SHIFT; 327 328 addr &= ~(psize - 1); 329 330 if (!kvmhv_on_pseries()) { 331 radix__flush_tlb_lpid_page(lpid, addr, psize); 332 return; 333 } 334 335 psi = shift_to_mmu_psize(pshift); 336 337 if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE)) { 338 rb = addr | (mmu_get_ap(psi) << PPC_BITLSHIFT(58)); 339 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(0, 0, 1), 340 lpid, rb); 341 } else { 342 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU, 343 H_RPTI_TYPE_NESTED | 344 H_RPTI_TYPE_TLB, 345 psize_to_rpti_pgsize(psi), 346 addr, addr + psize); 347 } 348 349 if (rc) 350 pr_err("KVM: TLB page invalidation hcall failed, rc=%ld\n", rc); 351} 352 353static void kvmppc_radix_flush_pwc(struct kvm *kvm, u64 lpid) 354{ 355 long rc; 356 357 if (!kvmhv_on_pseries()) { 358 radix__flush_pwc_lpid(lpid); 359 return; 360 } 361 362 if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE)) 363 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(1, 0, 1), 364 lpid, TLBIEL_INVAL_SET_LPID); 365 else 366 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU, 367 H_RPTI_TYPE_NESTED | 368 H_RPTI_TYPE_PWC, H_RPTI_PAGE_ALL, 369 0, -1UL); 370 if (rc) 371 pr_err("KVM: TLB PWC invalidation hcall failed, rc=%ld\n", rc); 372} 373 374static unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep, 375 unsigned long clr, unsigned long set, 376 unsigned long addr, unsigned int shift) 377{ 378 return __radix_pte_update(ptep, clr, set); 379} 380 381static void kvmppc_radix_set_pte_at(struct kvm *kvm, unsigned long addr, 382 pte_t *ptep, pte_t pte) 383{ 384 radix__set_pte_at(kvm->mm, addr, ptep, pte, 0); 385} 386 387static struct kmem_cache *kvm_pte_cache; 388static struct kmem_cache *kvm_pmd_cache; 389 390static pte_t *kvmppc_pte_alloc(void) 391{ 392 pte_t *pte; 393 394 pte = kmem_cache_alloc(kvm_pte_cache, GFP_KERNEL); 395 /* pmd_populate() will only reference _pa(pte). */ 396 kmemleak_ignore(pte); 397 398 return pte; 399} 400 401static void kvmppc_pte_free(pte_t *ptep) 402{ 403 kmem_cache_free(kvm_pte_cache, ptep); 404} 405 406static pmd_t *kvmppc_pmd_alloc(void) 407{ 408 pmd_t *pmd; 409 410 pmd = kmem_cache_alloc(kvm_pmd_cache, GFP_KERNEL); 411 /* pud_populate() will only reference _pa(pmd). */ 412 kmemleak_ignore(pmd); 413 414 return pmd; 415} 416 417static void kvmppc_pmd_free(pmd_t *pmdp) 418{ 419 kmem_cache_free(kvm_pmd_cache, pmdp); 420} 421 422/* Called with kvm->mmu_lock held */ 423void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa, 424 unsigned int shift, 425 const struct kvm_memory_slot *memslot, 426 u64 lpid) 427 428{ 429 unsigned long old; 430 unsigned long gfn = gpa >> PAGE_SHIFT; 431 unsigned long page_size = PAGE_SIZE; 432 unsigned long hpa; 433 434 old = kvmppc_radix_update_pte(kvm, pte, ~0UL, 0, gpa, shift); 435 kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid); 436 437 /* The following only applies to L1 entries */ 438 if (lpid != kvm->arch.lpid) 439 return; 440 441 if (!memslot) { 442 memslot = gfn_to_memslot(kvm, gfn); 443 if (!memslot) 444 return; 445 } 446 if (shift) { /* 1GB or 2MB page */ 447 page_size = 1ul << shift; 448 if (shift == PMD_SHIFT) 449 kvm->stat.num_2M_pages--; 450 else if (shift == PUD_SHIFT) 451 kvm->stat.num_1G_pages--; 452 } 453 454 gpa &= ~(page_size - 1); 455 hpa = old & PTE_RPN_MASK; 456 kvmhv_remove_nest_rmap_range(kvm, memslot, gpa, hpa, page_size); 457 458 if ((old & _PAGE_DIRTY) && memslot->dirty_bitmap) 459 kvmppc_update_dirty_map(memslot, gfn, page_size); 460} 461 462/* 463 * kvmppc_free_p?d are used to free existing page tables, and recursively 464 * descend and clear and free children. 465 * Callers are responsible for flushing the PWC. 466 * 467 * When page tables are being unmapped/freed as part of page fault path 468 * (full == false), valid ptes are generally not expected; however, there 469 * is one situation where they arise, which is when dirty page logging is 470 * turned off for a memslot while the VM is running. The new memslot 471 * becomes visible to page faults before the memslot commit function 472 * gets to flush the memslot, which can lead to a 2MB page mapping being 473 * installed for a guest physical address where there are already 64kB 474 * (or 4kB) mappings (of sub-pages of the same 2MB page). 475 */ 476static void kvmppc_unmap_free_pte(struct kvm *kvm, pte_t *pte, bool full, 477 u64 lpid) 478{ 479 if (full) { 480 memset(pte, 0, sizeof(long) << RADIX_PTE_INDEX_SIZE); 481 } else { 482 pte_t *p = pte; 483 unsigned long it; 484 485 for (it = 0; it < PTRS_PER_PTE; ++it, ++p) { 486 if (pte_val(*p) == 0) 487 continue; 488 kvmppc_unmap_pte(kvm, p, 489 pte_pfn(*p) << PAGE_SHIFT, 490 PAGE_SHIFT, NULL, lpid); 491 } 492 } 493 494 kvmppc_pte_free(pte); 495} 496 497static void kvmppc_unmap_free_pmd(struct kvm *kvm, pmd_t *pmd, bool full, 498 u64 lpid) 499{ 500 unsigned long im; 501 pmd_t *p = pmd; 502 503 for (im = 0; im < PTRS_PER_PMD; ++im, ++p) { 504 if (!pmd_present(*p)) 505 continue; 506 if (pmd_leaf(*p)) { 507 if (full) { 508 pmd_clear(p); 509 } else { 510 WARN_ON_ONCE(1); 511 kvmppc_unmap_pte(kvm, (pte_t *)p, 512 pte_pfn(*(pte_t *)p) << PAGE_SHIFT, 513 PMD_SHIFT, NULL, lpid); 514 } 515 } else { 516 pte_t *pte; 517 518 pte = pte_offset_kernel(p, 0); 519 kvmppc_unmap_free_pte(kvm, pte, full, lpid); 520 pmd_clear(p); 521 } 522 } 523 kvmppc_pmd_free(pmd); 524} 525 526static void kvmppc_unmap_free_pud(struct kvm *kvm, pud_t *pud, 527 u64 lpid) 528{ 529 unsigned long iu; 530 pud_t *p = pud; 531 532 for (iu = 0; iu < PTRS_PER_PUD; ++iu, ++p) { 533 if (!pud_present(*p)) 534 continue; 535 if (pud_leaf(*p)) { 536 pud_clear(p); 537 } else { 538 pmd_t *pmd; 539 540 pmd = pmd_offset(p, 0); 541 kvmppc_unmap_free_pmd(kvm, pmd, true, lpid); 542 pud_clear(p); 543 } 544 } 545 pud_free(kvm->mm, pud); 546} 547 548void kvmppc_free_pgtable_radix(struct kvm *kvm, pgd_t *pgd, u64 lpid) 549{ 550 unsigned long ig; 551 552 for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) { 553 p4d_t *p4d = p4d_offset(pgd, 0); 554 pud_t *pud; 555 556 if (!p4d_present(*p4d)) 557 continue; 558 pud = pud_offset(p4d, 0); 559 kvmppc_unmap_free_pud(kvm, pud, lpid); 560 p4d_clear(p4d); 561 } 562} 563 564void kvmppc_free_radix(struct kvm *kvm) 565{ 566 if (kvm->arch.pgtable) { 567 kvmppc_free_pgtable_radix(kvm, kvm->arch.pgtable, 568 kvm->arch.lpid); 569 pgd_free(kvm->mm, kvm->arch.pgtable); 570 kvm->arch.pgtable = NULL; 571 } 572} 573 574static void kvmppc_unmap_free_pmd_entry_table(struct kvm *kvm, pmd_t *pmd, 575 unsigned long gpa, u64 lpid) 576{ 577 pte_t *pte = pte_offset_kernel(pmd, 0); 578 579 /* 580 * Clearing the pmd entry then flushing the PWC ensures that the pte 581 * page no longer be cached by the MMU, so can be freed without 582 * flushing the PWC again. 583 */ 584 pmd_clear(pmd); 585 kvmppc_radix_flush_pwc(kvm, lpid); 586 587 kvmppc_unmap_free_pte(kvm, pte, false, lpid); 588} 589 590static void kvmppc_unmap_free_pud_entry_table(struct kvm *kvm, pud_t *pud, 591 unsigned long gpa, u64 lpid) 592{ 593 pmd_t *pmd = pmd_offset(pud, 0); 594 595 /* 596 * Clearing the pud entry then flushing the PWC ensures that the pmd 597 * page and any children pte pages will no longer be cached by the MMU, 598 * so can be freed without flushing the PWC again. 599 */ 600 pud_clear(pud); 601 kvmppc_radix_flush_pwc(kvm, lpid); 602 603 kvmppc_unmap_free_pmd(kvm, pmd, false, lpid); 604} 605 606/* 607 * There are a number of bits which may differ between different faults to 608 * the same partition scope entry. RC bits, in the course of cleaning and 609 * aging. And the write bit can change, either the access could have been 610 * upgraded, or a read fault could happen concurrently with a write fault 611 * that sets those bits first. 612 */ 613#define PTE_BITS_MUST_MATCH (~(_PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)) 614 615int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte, 616 unsigned long gpa, unsigned int level, 617 unsigned long mmu_seq, u64 lpid, 618 unsigned long *rmapp, struct rmap_nested **n_rmap) 619{ 620 pgd_t *pgd; 621 p4d_t *p4d; 622 pud_t *pud, *new_pud = NULL; 623 pmd_t *pmd, *new_pmd = NULL; 624 pte_t *ptep, *new_ptep = NULL; 625 int ret; 626 627 /* Traverse the guest's 2nd-level tree, allocate new levels needed */ 628 pgd = pgtable + pgd_index(gpa); 629 p4d = p4d_offset(pgd, gpa); 630 631 pud = NULL; 632 if (p4d_present(*p4d)) 633 pud = pud_offset(p4d, gpa); 634 else 635 new_pud = pud_alloc_one(kvm->mm, gpa); 636 637 pmd = NULL; 638 if (pud && pud_present(*pud) && !pud_leaf(*pud)) 639 pmd = pmd_offset(pud, gpa); 640 else if (level <= 1) 641 new_pmd = kvmppc_pmd_alloc(); 642 643 if (level == 0 && !(pmd && pmd_present(*pmd) && !pmd_leaf(*pmd))) 644 new_ptep = kvmppc_pte_alloc(); 645 646 /* Check if we might have been invalidated; let the guest retry if so */ 647 spin_lock(&kvm->mmu_lock); 648 ret = -EAGAIN; 649 if (mmu_invalidate_retry(kvm, mmu_seq)) 650 goto out_unlock; 651 652 /* Now traverse again under the lock and change the tree */ 653 ret = -ENOMEM; 654 if (p4d_none(*p4d)) { 655 if (!new_pud) 656 goto out_unlock; 657 p4d_populate(kvm->mm, p4d, new_pud); 658 new_pud = NULL; 659 } 660 pud = pud_offset(p4d, gpa); 661 if (pud_leaf(*pud)) { 662 unsigned long hgpa = gpa & PUD_MASK; 663 664 /* Check if we raced and someone else has set the same thing */ 665 if (level == 2) { 666 if (pud_raw(*pud) == pte_raw(pte)) { 667 ret = 0; 668 goto out_unlock; 669 } 670 /* Valid 1GB page here already, add our extra bits */ 671 WARN_ON_ONCE((pud_val(*pud) ^ pte_val(pte)) & 672 PTE_BITS_MUST_MATCH); 673 kvmppc_radix_update_pte(kvm, (pte_t *)pud, 674 0, pte_val(pte), hgpa, PUD_SHIFT); 675 ret = 0; 676 goto out_unlock; 677 } 678 /* 679 * If we raced with another CPU which has just put 680 * a 1GB pte in after we saw a pmd page, try again. 681 */ 682 if (!new_pmd) { 683 ret = -EAGAIN; 684 goto out_unlock; 685 } 686 /* Valid 1GB page here already, remove it */ 687 kvmppc_unmap_pte(kvm, (pte_t *)pud, hgpa, PUD_SHIFT, NULL, 688 lpid); 689 } 690 if (level == 2) { 691 if (!pud_none(*pud)) { 692 /* 693 * There's a page table page here, but we wanted to 694 * install a large page, so remove and free the page 695 * table page. 696 */ 697 kvmppc_unmap_free_pud_entry_table(kvm, pud, gpa, lpid); 698 } 699 kvmppc_radix_set_pte_at(kvm, gpa, (pte_t *)pud, pte); 700 if (rmapp && n_rmap) 701 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap); 702 ret = 0; 703 goto out_unlock; 704 } 705 if (pud_none(*pud)) { 706 if (!new_pmd) 707 goto out_unlock; 708 pud_populate(kvm->mm, pud, new_pmd); 709 new_pmd = NULL; 710 } 711 pmd = pmd_offset(pud, gpa); 712 if (pmd_leaf(*pmd)) { 713 unsigned long lgpa = gpa & PMD_MASK; 714 715 /* Check if we raced and someone else has set the same thing */ 716 if (level == 1) { 717 if (pmd_raw(*pmd) == pte_raw(pte)) { 718 ret = 0; 719 goto out_unlock; 720 } 721 /* Valid 2MB page here already, add our extra bits */ 722 WARN_ON_ONCE((pmd_val(*pmd) ^ pte_val(pte)) & 723 PTE_BITS_MUST_MATCH); 724 kvmppc_radix_update_pte(kvm, pmdp_ptep(pmd), 725 0, pte_val(pte), lgpa, PMD_SHIFT); 726 ret = 0; 727 goto out_unlock; 728 } 729 730 /* 731 * If we raced with another CPU which has just put 732 * a 2MB pte in after we saw a pte page, try again. 733 */ 734 if (!new_ptep) { 735 ret = -EAGAIN; 736 goto out_unlock; 737 } 738 /* Valid 2MB page here already, remove it */ 739 kvmppc_unmap_pte(kvm, pmdp_ptep(pmd), lgpa, PMD_SHIFT, NULL, 740 lpid); 741 } 742 if (level == 1) { 743 if (!pmd_none(*pmd)) { 744 /* 745 * There's a page table page here, but we wanted to 746 * install a large page, so remove and free the page 747 * table page. 748 */ 749 kvmppc_unmap_free_pmd_entry_table(kvm, pmd, gpa, lpid); 750 } 751 kvmppc_radix_set_pte_at(kvm, gpa, pmdp_ptep(pmd), pte); 752 if (rmapp && n_rmap) 753 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap); 754 ret = 0; 755 goto out_unlock; 756 } 757 if (pmd_none(*pmd)) { 758 if (!new_ptep) 759 goto out_unlock; 760 pmd_populate(kvm->mm, pmd, new_ptep); 761 new_ptep = NULL; 762 } 763 ptep = pte_offset_kernel(pmd, gpa); 764 if (pte_present(*ptep)) { 765 /* Check if someone else set the same thing */ 766 if (pte_raw(*ptep) == pte_raw(pte)) { 767 ret = 0; 768 goto out_unlock; 769 } 770 /* Valid page here already, add our extra bits */ 771 WARN_ON_ONCE((pte_val(*ptep) ^ pte_val(pte)) & 772 PTE_BITS_MUST_MATCH); 773 kvmppc_radix_update_pte(kvm, ptep, 0, pte_val(pte), gpa, 0); 774 ret = 0; 775 goto out_unlock; 776 } 777 kvmppc_radix_set_pte_at(kvm, gpa, ptep, pte); 778 if (rmapp && n_rmap) 779 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap); 780 ret = 0; 781 782 out_unlock: 783 spin_unlock(&kvm->mmu_lock); 784 if (new_pud) 785 pud_free(kvm->mm, new_pud); 786 if (new_pmd) 787 kvmppc_pmd_free(new_pmd); 788 if (new_ptep) 789 kvmppc_pte_free(new_ptep); 790 return ret; 791} 792 793bool kvmppc_hv_handle_set_rc(struct kvm *kvm, bool nested, bool writing, 794 unsigned long gpa, u64 lpid) 795{ 796 unsigned long pgflags; 797 unsigned int shift; 798 pte_t *ptep; 799 800 /* 801 * Need to set an R or C bit in the 2nd-level tables; 802 * since we are just helping out the hardware here, 803 * it is sufficient to do what the hardware does. 804 */ 805 pgflags = _PAGE_ACCESSED; 806 if (writing) 807 pgflags |= _PAGE_DIRTY; 808 809 if (nested) 810 ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift); 811 else 812 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 813 814 if (ptep && pte_present(*ptep) && (!writing || pte_write(*ptep))) { 815 kvmppc_radix_update_pte(kvm, ptep, 0, pgflags, gpa, shift); 816 return true; 817 } 818 return false; 819} 820 821int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu, 822 unsigned long gpa, 823 struct kvm_memory_slot *memslot, 824 bool writing, bool kvm_ro, 825 pte_t *inserted_pte, unsigned int *levelp) 826{ 827 struct kvm *kvm = vcpu->kvm; 828 struct page *page = NULL; 829 unsigned long mmu_seq; 830 unsigned long hva, gfn = gpa >> PAGE_SHIFT; 831 bool upgrade_write = false; 832 bool *upgrade_p = &upgrade_write; 833 pte_t pte, *ptep; 834 unsigned int shift, level; 835 int ret; 836 bool large_enable; 837 838 /* used to check for invalidations in progress */ 839 mmu_seq = kvm->mmu_invalidate_seq; 840 smp_rmb(); 841 842 /* 843 * Do a fast check first, since __gfn_to_pfn_memslot doesn't 844 * do it with !atomic && !async, which is how we call it. 845 * We always ask for write permission since the common case 846 * is that the page is writable. 847 */ 848 hva = gfn_to_hva_memslot(memslot, gfn); 849 if (!kvm_ro && get_user_page_fast_only(hva, FOLL_WRITE, &page)) { 850 upgrade_write = true; 851 } else { 852 unsigned long pfn; 853 854 /* Call KVM generic code to do the slow-path check */ 855 pfn = __gfn_to_pfn_memslot(memslot, gfn, false, false, NULL, 856 writing, upgrade_p, NULL); 857 if (is_error_noslot_pfn(pfn)) 858 return -EFAULT; 859 page = NULL; 860 if (pfn_valid(pfn)) { 861 page = pfn_to_page(pfn); 862 if (PageReserved(page)) 863 page = NULL; 864 } 865 } 866 867 /* 868 * Read the PTE from the process' radix tree and use that 869 * so we get the shift and attribute bits. 870 */ 871 spin_lock(&kvm->mmu_lock); 872 ptep = find_kvm_host_pte(kvm, mmu_seq, hva, &shift); 873 pte = __pte(0); 874 if (ptep) 875 pte = READ_ONCE(*ptep); 876 spin_unlock(&kvm->mmu_lock); 877 /* 878 * If the PTE disappeared temporarily due to a THP 879 * collapse, just return and let the guest try again. 880 */ 881 if (!pte_present(pte)) { 882 if (page) 883 put_page(page); 884 return RESUME_GUEST; 885 } 886 887 /* If we're logging dirty pages, always map single pages */ 888 large_enable = !(memslot->flags & KVM_MEM_LOG_DIRTY_PAGES); 889 890 /* Get pte level from shift/size */ 891 if (large_enable && shift == PUD_SHIFT && 892 (gpa & (PUD_SIZE - PAGE_SIZE)) == 893 (hva & (PUD_SIZE - PAGE_SIZE))) { 894 level = 2; 895 } else if (large_enable && shift == PMD_SHIFT && 896 (gpa & (PMD_SIZE - PAGE_SIZE)) == 897 (hva & (PMD_SIZE - PAGE_SIZE))) { 898 level = 1; 899 } else { 900 level = 0; 901 if (shift > PAGE_SHIFT) { 902 /* 903 * If the pte maps more than one page, bring over 904 * bits from the virtual address to get the real 905 * address of the specific single page we want. 906 */ 907 unsigned long rpnmask = (1ul << shift) - PAGE_SIZE; 908 pte = __pte(pte_val(pte) | (hva & rpnmask)); 909 } 910 } 911 912 pte = __pte(pte_val(pte) | _PAGE_EXEC | _PAGE_ACCESSED); 913 if (writing || upgrade_write) { 914 if (pte_val(pte) & _PAGE_WRITE) 915 pte = __pte(pte_val(pte) | _PAGE_DIRTY); 916 } else { 917 pte = __pte(pte_val(pte) & ~(_PAGE_WRITE | _PAGE_DIRTY)); 918 } 919 920 /* Allocate space in the tree and write the PTE */ 921 ret = kvmppc_create_pte(kvm, kvm->arch.pgtable, pte, gpa, level, 922 mmu_seq, kvm->arch.lpid, NULL, NULL); 923 if (inserted_pte) 924 *inserted_pte = pte; 925 if (levelp) 926 *levelp = level; 927 928 if (page) { 929 if (!ret && (pte_val(pte) & _PAGE_WRITE)) 930 set_page_dirty_lock(page); 931 put_page(page); 932 } 933 934 /* Increment number of large pages if we (successfully) inserted one */ 935 if (!ret) { 936 if (level == 1) 937 kvm->stat.num_2M_pages++; 938 else if (level == 2) 939 kvm->stat.num_1G_pages++; 940 } 941 942 return ret; 943} 944 945int kvmppc_book3s_radix_page_fault(struct kvm_vcpu *vcpu, 946 unsigned long ea, unsigned long dsisr) 947{ 948 struct kvm *kvm = vcpu->kvm; 949 unsigned long gpa, gfn; 950 struct kvm_memory_slot *memslot; 951 long ret; 952 bool writing = !!(dsisr & DSISR_ISSTORE); 953 bool kvm_ro = false; 954 955 /* Check for unusual errors */ 956 if (dsisr & DSISR_UNSUPP_MMU) { 957 pr_err("KVM: Got unsupported MMU fault\n"); 958 return -EFAULT; 959 } 960 if (dsisr & DSISR_BADACCESS) { 961 /* Reflect to the guest as DSI */ 962 pr_err("KVM: Got radix HV page fault with DSISR=%lx\n", dsisr); 963 kvmppc_core_queue_data_storage(vcpu, 964 kvmppc_get_msr(vcpu) & SRR1_PREFIXED, 965 ea, dsisr); 966 return RESUME_GUEST; 967 } 968 969 /* Translate the logical address */ 970 gpa = vcpu->arch.fault_gpa & ~0xfffUL; 971 gpa &= ~0xF000000000000000ul; 972 gfn = gpa >> PAGE_SHIFT; 973 if (!(dsisr & DSISR_PRTABLE_FAULT)) 974 gpa |= ea & 0xfff; 975 976 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 977 return kvmppc_send_page_to_uv(kvm, gfn); 978 979 /* Get the corresponding memslot */ 980 memslot = gfn_to_memslot(kvm, gfn); 981 982 /* No memslot means it's an emulated MMIO region */ 983 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) { 984 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS | 985 DSISR_SET_RC)) { 986 /* 987 * Bad address in guest page table tree, or other 988 * unusual error - reflect it to the guest as DSI. 989 */ 990 kvmppc_core_queue_data_storage(vcpu, 991 kvmppc_get_msr(vcpu) & SRR1_PREFIXED, 992 ea, dsisr); 993 return RESUME_GUEST; 994 } 995 return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing); 996 } 997 998 if (memslot->flags & KVM_MEM_READONLY) { 999 if (writing) { 1000 /* give the guest a DSI */ 1001 kvmppc_core_queue_data_storage(vcpu, 1002 kvmppc_get_msr(vcpu) & SRR1_PREFIXED, 1003 ea, DSISR_ISSTORE | DSISR_PROTFAULT); 1004 return RESUME_GUEST; 1005 } 1006 kvm_ro = true; 1007 } 1008 1009 /* Failed to set the reference/change bits */ 1010 if (dsisr & DSISR_SET_RC) { 1011 spin_lock(&kvm->mmu_lock); 1012 if (kvmppc_hv_handle_set_rc(kvm, false, writing, 1013 gpa, kvm->arch.lpid)) 1014 dsisr &= ~DSISR_SET_RC; 1015 spin_unlock(&kvm->mmu_lock); 1016 1017 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE | 1018 DSISR_PROTFAULT | DSISR_SET_RC))) 1019 return RESUME_GUEST; 1020 } 1021 1022 /* Try to insert a pte */ 1023 ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot, writing, 1024 kvm_ro, NULL, NULL); 1025 1026 if (ret == 0 || ret == -EAGAIN) 1027 ret = RESUME_GUEST; 1028 return ret; 1029} 1030 1031/* Called with kvm->mmu_lock held */ 1032void kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, 1033 unsigned long gfn) 1034{ 1035 pte_t *ptep; 1036 unsigned long gpa = gfn << PAGE_SHIFT; 1037 unsigned int shift; 1038 1039 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) { 1040 uv_page_inval(kvm->arch.lpid, gpa, PAGE_SHIFT); 1041 return; 1042 } 1043 1044 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1045 if (ptep && pte_present(*ptep)) 1046 kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot, 1047 kvm->arch.lpid); 1048} 1049 1050/* Called with kvm->mmu_lock held */ 1051bool kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, 1052 unsigned long gfn) 1053{ 1054 pte_t *ptep; 1055 unsigned long gpa = gfn << PAGE_SHIFT; 1056 unsigned int shift; 1057 bool ref = false; 1058 unsigned long old, *rmapp; 1059 1060 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1061 return ref; 1062 1063 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1064 if (ptep && pte_present(*ptep) && pte_young(*ptep)) { 1065 old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_ACCESSED, 0, 1066 gpa, shift); 1067 /* XXX need to flush tlb here? */ 1068 /* Also clear bit in ptes in shadow pgtable for nested guests */ 1069 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 1070 kvmhv_update_nest_rmap_rc_list(kvm, rmapp, _PAGE_ACCESSED, 0, 1071 old & PTE_RPN_MASK, 1072 1UL << shift); 1073 ref = true; 1074 } 1075 return ref; 1076} 1077 1078/* Called with kvm->mmu_lock held */ 1079bool kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, 1080 unsigned long gfn) 1081 1082{ 1083 pte_t *ptep; 1084 unsigned long gpa = gfn << PAGE_SHIFT; 1085 unsigned int shift; 1086 bool ref = false; 1087 1088 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1089 return ref; 1090 1091 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1092 if (ptep && pte_present(*ptep) && pte_young(*ptep)) 1093 ref = true; 1094 return ref; 1095} 1096 1097/* Returns the number of PAGE_SIZE pages that are dirty */ 1098static int kvm_radix_test_clear_dirty(struct kvm *kvm, 1099 struct kvm_memory_slot *memslot, int pagenum) 1100{ 1101 unsigned long gfn = memslot->base_gfn + pagenum; 1102 unsigned long gpa = gfn << PAGE_SHIFT; 1103 pte_t *ptep, pte; 1104 unsigned int shift; 1105 int ret = 0; 1106 unsigned long old, *rmapp; 1107 1108 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1109 return ret; 1110 1111 /* 1112 * For performance reasons we don't hold kvm->mmu_lock while walking the 1113 * partition scoped table. 1114 */ 1115 ptep = find_kvm_secondary_pte_unlocked(kvm, gpa, &shift); 1116 if (!ptep) 1117 return 0; 1118 1119 pte = READ_ONCE(*ptep); 1120 if (pte_present(pte) && pte_dirty(pte)) { 1121 spin_lock(&kvm->mmu_lock); 1122 /* 1123 * Recheck the pte again 1124 */ 1125 if (pte_val(pte) != pte_val(*ptep)) { 1126 /* 1127 * We have KVM_MEM_LOG_DIRTY_PAGES enabled. Hence we can 1128 * only find PAGE_SIZE pte entries here. We can continue 1129 * to use the pte addr returned by above page table 1130 * walk. 1131 */ 1132 if (!pte_present(*ptep) || !pte_dirty(*ptep)) { 1133 spin_unlock(&kvm->mmu_lock); 1134 return 0; 1135 } 1136 } 1137 1138 ret = 1; 1139 VM_BUG_ON(shift); 1140 old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_DIRTY, 0, 1141 gpa, shift); 1142 kvmppc_radix_tlbie_page(kvm, gpa, shift, kvm->arch.lpid); 1143 /* Also clear bit in ptes in shadow pgtable for nested guests */ 1144 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 1145 kvmhv_update_nest_rmap_rc_list(kvm, rmapp, _PAGE_DIRTY, 0, 1146 old & PTE_RPN_MASK, 1147 1UL << shift); 1148 spin_unlock(&kvm->mmu_lock); 1149 } 1150 return ret; 1151} 1152 1153long kvmppc_hv_get_dirty_log_radix(struct kvm *kvm, 1154 struct kvm_memory_slot *memslot, unsigned long *map) 1155{ 1156 unsigned long i, j; 1157 int npages; 1158 1159 for (i = 0; i < memslot->npages; i = j) { 1160 npages = kvm_radix_test_clear_dirty(kvm, memslot, i); 1161 1162 /* 1163 * Note that if npages > 0 then i must be a multiple of npages, 1164 * since huge pages are only used to back the guest at guest 1165 * real addresses that are a multiple of their size. 1166 * Since we have at most one PTE covering any given guest 1167 * real address, if npages > 1 we can skip to i + npages. 1168 */ 1169 j = i + 1; 1170 if (npages) { 1171 set_dirty_bits(map, i, npages); 1172 j = i + npages; 1173 } 1174 } 1175 return 0; 1176} 1177 1178void kvmppc_radix_flush_memslot(struct kvm *kvm, 1179 const struct kvm_memory_slot *memslot) 1180{ 1181 unsigned long n; 1182 pte_t *ptep; 1183 unsigned long gpa; 1184 unsigned int shift; 1185 1186 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_START) 1187 kvmppc_uvmem_drop_pages(memslot, kvm, true); 1188 1189 if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) 1190 return; 1191 1192 gpa = memslot->base_gfn << PAGE_SHIFT; 1193 spin_lock(&kvm->mmu_lock); 1194 for (n = memslot->npages; n; --n) { 1195 ptep = find_kvm_secondary_pte(kvm, gpa, &shift); 1196 if (ptep && pte_present(*ptep)) 1197 kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot, 1198 kvm->arch.lpid); 1199 gpa += PAGE_SIZE; 1200 } 1201 /* 1202 * Increase the mmu notifier sequence number to prevent any page 1203 * fault that read the memslot earlier from writing a PTE. 1204 */ 1205 kvm->mmu_invalidate_seq++; 1206 spin_unlock(&kvm->mmu_lock); 1207} 1208 1209static void add_rmmu_ap_encoding(struct kvm_ppc_rmmu_info *info, 1210 int psize, int *indexp) 1211{ 1212 if (!mmu_psize_defs[psize].shift) 1213 return; 1214 info->ap_encodings[*indexp] = mmu_psize_defs[psize].shift | 1215 (mmu_psize_defs[psize].ap << 29); 1216 ++(*indexp); 1217} 1218 1219int kvmhv_get_rmmu_info(struct kvm *kvm, struct kvm_ppc_rmmu_info *info) 1220{ 1221 int i; 1222 1223 if (!radix_enabled()) 1224 return -EINVAL; 1225 memset(info, 0, sizeof(*info)); 1226 1227 /* 4k page size */ 1228 info->geometries[0].page_shift = 12; 1229 info->geometries[0].level_bits[0] = 9; 1230 for (i = 1; i < 4; ++i) 1231 info->geometries[0].level_bits[i] = p9_supported_radix_bits[i]; 1232 /* 64k page size */ 1233 info->geometries[1].page_shift = 16; 1234 for (i = 0; i < 4; ++i) 1235 info->geometries[1].level_bits[i] = p9_supported_radix_bits[i]; 1236 1237 i = 0; 1238 add_rmmu_ap_encoding(info, MMU_PAGE_4K, &i); 1239 add_rmmu_ap_encoding(info, MMU_PAGE_64K, &i); 1240 add_rmmu_ap_encoding(info, MMU_PAGE_2M, &i); 1241 add_rmmu_ap_encoding(info, MMU_PAGE_1G, &i); 1242 1243 return 0; 1244} 1245 1246int kvmppc_init_vm_radix(struct kvm *kvm) 1247{ 1248 kvm->arch.pgtable = pgd_alloc(kvm->mm); 1249 if (!kvm->arch.pgtable) 1250 return -ENOMEM; 1251 return 0; 1252} 1253 1254static void pte_ctor(void *addr) 1255{ 1256 memset(addr, 0, RADIX_PTE_TABLE_SIZE); 1257} 1258 1259static void pmd_ctor(void *addr) 1260{ 1261 memset(addr, 0, RADIX_PMD_TABLE_SIZE); 1262} 1263 1264struct debugfs_radix_state { 1265 struct kvm *kvm; 1266 struct mutex mutex; 1267 unsigned long gpa; 1268 int lpid; 1269 int chars_left; 1270 int buf_index; 1271 char buf[128]; 1272 u8 hdr; 1273}; 1274 1275static int debugfs_radix_open(struct inode *inode, struct file *file) 1276{ 1277 struct kvm *kvm = inode->i_private; 1278 struct debugfs_radix_state *p; 1279 1280 p = kzalloc(sizeof(*p), GFP_KERNEL); 1281 if (!p) 1282 return -ENOMEM; 1283 1284 kvm_get_kvm(kvm); 1285 p->kvm = kvm; 1286 mutex_init(&p->mutex); 1287 file->private_data = p; 1288 1289 return nonseekable_open(inode, file); 1290} 1291 1292static int debugfs_radix_release(struct inode *inode, struct file *file) 1293{ 1294 struct debugfs_radix_state *p = file->private_data; 1295 1296 kvm_put_kvm(p->kvm); 1297 kfree(p); 1298 return 0; 1299} 1300 1301static ssize_t debugfs_radix_read(struct file *file, char __user *buf, 1302 size_t len, loff_t *ppos) 1303{ 1304 struct debugfs_radix_state *p = file->private_data; 1305 ssize_t ret, r; 1306 unsigned long n; 1307 struct kvm *kvm; 1308 unsigned long gpa; 1309 pgd_t *pgt; 1310 struct kvm_nested_guest *nested; 1311 pgd_t *pgdp; 1312 p4d_t p4d, *p4dp; 1313 pud_t pud, *pudp; 1314 pmd_t pmd, *pmdp; 1315 pte_t *ptep; 1316 int shift; 1317 unsigned long pte; 1318 1319 kvm = p->kvm; 1320 if (!kvm_is_radix(kvm)) 1321 return 0; 1322 1323 ret = mutex_lock_interruptible(&p->mutex); 1324 if (ret) 1325 return ret; 1326 1327 if (p->chars_left) { 1328 n = p->chars_left; 1329 if (n > len) 1330 n = len; 1331 r = copy_to_user(buf, p->buf + p->buf_index, n); 1332 n -= r; 1333 p->chars_left -= n; 1334 p->buf_index += n; 1335 buf += n; 1336 len -= n; 1337 ret = n; 1338 if (r) { 1339 if (!n) 1340 ret = -EFAULT; 1341 goto out; 1342 } 1343 } 1344 1345 gpa = p->gpa; 1346 nested = NULL; 1347 pgt = NULL; 1348 while (len != 0 && p->lpid >= 0) { 1349 if (gpa >= RADIX_PGTABLE_RANGE) { 1350 gpa = 0; 1351 pgt = NULL; 1352 if (nested) { 1353 kvmhv_put_nested(nested); 1354 nested = NULL; 1355 } 1356 p->lpid = kvmhv_nested_next_lpid(kvm, p->lpid); 1357 p->hdr = 0; 1358 if (p->lpid < 0) 1359 break; 1360 } 1361 if (!pgt) { 1362 if (p->lpid == 0) { 1363 pgt = kvm->arch.pgtable; 1364 } else { 1365 nested = kvmhv_get_nested(kvm, p->lpid, false); 1366 if (!nested) { 1367 gpa = RADIX_PGTABLE_RANGE; 1368 continue; 1369 } 1370 pgt = nested->shadow_pgtable; 1371 } 1372 } 1373 n = 0; 1374 if (!p->hdr) { 1375 if (p->lpid > 0) 1376 n = scnprintf(p->buf, sizeof(p->buf), 1377 "\nNested LPID %d: ", p->lpid); 1378 n += scnprintf(p->buf + n, sizeof(p->buf) - n, 1379 "pgdir: %lx\n", (unsigned long)pgt); 1380 p->hdr = 1; 1381 goto copy; 1382 } 1383 1384 pgdp = pgt + pgd_index(gpa); 1385 p4dp = p4d_offset(pgdp, gpa); 1386 p4d = READ_ONCE(*p4dp); 1387 if (!(p4d_val(p4d) & _PAGE_PRESENT)) { 1388 gpa = (gpa & P4D_MASK) + P4D_SIZE; 1389 continue; 1390 } 1391 1392 pudp = pud_offset(&p4d, gpa); 1393 pud = READ_ONCE(*pudp); 1394 if (!(pud_val(pud) & _PAGE_PRESENT)) { 1395 gpa = (gpa & PUD_MASK) + PUD_SIZE; 1396 continue; 1397 } 1398 if (pud_val(pud) & _PAGE_PTE) { 1399 pte = pud_val(pud); 1400 shift = PUD_SHIFT; 1401 goto leaf; 1402 } 1403 1404 pmdp = pmd_offset(&pud, gpa); 1405 pmd = READ_ONCE(*pmdp); 1406 if (!(pmd_val(pmd) & _PAGE_PRESENT)) { 1407 gpa = (gpa & PMD_MASK) + PMD_SIZE; 1408 continue; 1409 } 1410 if (pmd_val(pmd) & _PAGE_PTE) { 1411 pte = pmd_val(pmd); 1412 shift = PMD_SHIFT; 1413 goto leaf; 1414 } 1415 1416 ptep = pte_offset_kernel(&pmd, gpa); 1417 pte = pte_val(READ_ONCE(*ptep)); 1418 if (!(pte & _PAGE_PRESENT)) { 1419 gpa += PAGE_SIZE; 1420 continue; 1421 } 1422 shift = PAGE_SHIFT; 1423 leaf: 1424 n = scnprintf(p->buf, sizeof(p->buf), 1425 " %lx: %lx %d\n", gpa, pte, shift); 1426 gpa += 1ul << shift; 1427 copy: 1428 p->chars_left = n; 1429 if (n > len) 1430 n = len; 1431 r = copy_to_user(buf, p->buf, n); 1432 n -= r; 1433 p->chars_left -= n; 1434 p->buf_index = n; 1435 buf += n; 1436 len -= n; 1437 ret += n; 1438 if (r) { 1439 if (!ret) 1440 ret = -EFAULT; 1441 break; 1442 } 1443 } 1444 p->gpa = gpa; 1445 if (nested) 1446 kvmhv_put_nested(nested); 1447 1448 out: 1449 mutex_unlock(&p->mutex); 1450 return ret; 1451} 1452 1453static ssize_t debugfs_radix_write(struct file *file, const char __user *buf, 1454 size_t len, loff_t *ppos) 1455{ 1456 return -EACCES; 1457} 1458 1459static const struct file_operations debugfs_radix_fops = { 1460 .owner = THIS_MODULE, 1461 .open = debugfs_radix_open, 1462 .release = debugfs_radix_release, 1463 .read = debugfs_radix_read, 1464 .write = debugfs_radix_write, 1465 .llseek = generic_file_llseek, 1466}; 1467 1468void kvmhv_radix_debugfs_init(struct kvm *kvm) 1469{ 1470 debugfs_create_file("radix", 0400, kvm->debugfs_dentry, kvm, 1471 &debugfs_radix_fops); 1472} 1473 1474int kvmppc_radix_init(void) 1475{ 1476 unsigned long size = sizeof(void *) << RADIX_PTE_INDEX_SIZE; 1477 1478 kvm_pte_cache = kmem_cache_create("kvm-pte", size, size, 0, pte_ctor); 1479 if (!kvm_pte_cache) 1480 return -ENOMEM; 1481 1482 size = sizeof(void *) << RADIX_PMD_INDEX_SIZE; 1483 1484 kvm_pmd_cache = kmem_cache_create("kvm-pmd", size, size, 0, pmd_ctor); 1485 if (!kvm_pmd_cache) { 1486 kmem_cache_destroy(kvm_pte_cache); 1487 return -ENOMEM; 1488 } 1489 1490 return 0; 1491} 1492 1493void kvmppc_radix_exit(void) 1494{ 1495 kmem_cache_destroy(kvm_pte_cache); 1496 kmem_cache_destroy(kvm_pmd_cache); 1497} 1498