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