1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2019 Western Digital Corporation or its affiliates. 4 * 5 * Authors: 6 * Anup Patel <anup.patel@wdc.com> 7 */ 8 9 #include <linux/bitops.h> 10 #include <linux/errno.h> 11 #include <linux/err.h> 12 #include <linux/hugetlb.h> 13 #include <linux/module.h> 14 #include <linux/uaccess.h> 15 #include <linux/vmalloc.h> 16 #include <linux/kvm_host.h> 17 #include <linux/sched/signal.h> 18 #include <asm/csr.h> 19 #include <asm/page.h> 20 #include <asm/pgtable.h> 21 22 #ifdef CONFIG_64BIT 23 static unsigned long gstage_mode __ro_after_init = (HGATP_MODE_SV39X4 << HGATP_MODE_SHIFT); 24 static unsigned long gstage_pgd_levels __ro_after_init = 3; 25 #define gstage_index_bits 9 26 #else 27 static unsigned long gstage_mode __ro_after_init = (HGATP_MODE_SV32X4 << HGATP_MODE_SHIFT); 28 static unsigned long gstage_pgd_levels __ro_after_init = 2; 29 #define gstage_index_bits 10 30 #endif 31 32 #define gstage_pgd_xbits 2 33 #define gstage_pgd_size (1UL << (HGATP_PAGE_SHIFT + gstage_pgd_xbits)) 34 #define gstage_gpa_bits (HGATP_PAGE_SHIFT + \ 35 (gstage_pgd_levels * gstage_index_bits) + \ 36 gstage_pgd_xbits) 37 #define gstage_gpa_size ((gpa_t)(1ULL << gstage_gpa_bits)) 38 39 #define gstage_pte_leaf(__ptep) \ 40 (pte_val(*(__ptep)) & (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)) 41 42 static inline unsigned long gstage_pte_index(gpa_t addr, u32 level) 43 { 44 unsigned long mask; 45 unsigned long shift = HGATP_PAGE_SHIFT + (gstage_index_bits * level); 46 47 if (level == (gstage_pgd_levels - 1)) 48 mask = (PTRS_PER_PTE * (1UL << gstage_pgd_xbits)) - 1; 49 else 50 mask = PTRS_PER_PTE - 1; 51 52 return (addr >> shift) & mask; 53 } 54 55 static inline unsigned long gstage_pte_page_vaddr(pte_t pte) 56 { 57 return (unsigned long)pfn_to_virt(__page_val_to_pfn(pte_val(pte))); 58 } 59 60 static int gstage_page_size_to_level(unsigned long page_size, u32 *out_level) 61 { 62 u32 i; 63 unsigned long psz = 1UL << 12; 64 65 for (i = 0; i < gstage_pgd_levels; i++) { 66 if (page_size == (psz << (i * gstage_index_bits))) { 67 *out_level = i; 68 return 0; 69 } 70 } 71 72 return -EINVAL; 73 } 74 75 static int gstage_level_to_page_order(u32 level, unsigned long *out_pgorder) 76 { 77 if (gstage_pgd_levels < level) 78 return -EINVAL; 79 80 *out_pgorder = 12 + (level * gstage_index_bits); 81 return 0; 82 } 83 84 static int gstage_level_to_page_size(u32 level, unsigned long *out_pgsize) 85 { 86 int rc; 87 unsigned long page_order = PAGE_SHIFT; 88 89 rc = gstage_level_to_page_order(level, &page_order); 90 if (rc) 91 return rc; 92 93 *out_pgsize = BIT(page_order); 94 return 0; 95 } 96 97 static bool gstage_get_leaf_entry(struct kvm *kvm, gpa_t addr, 98 pte_t **ptepp, u32 *ptep_level) 99 { 100 pte_t *ptep; 101 u32 current_level = gstage_pgd_levels - 1; 102 103 *ptep_level = current_level; 104 ptep = (pte_t *)kvm->arch.pgd; 105 ptep = &ptep[gstage_pte_index(addr, current_level)]; 106 while (ptep && pte_val(ptep_get(ptep))) { 107 if (gstage_pte_leaf(ptep)) { 108 *ptep_level = current_level; 109 *ptepp = ptep; 110 return true; 111 } 112 113 if (current_level) { 114 current_level--; 115 *ptep_level = current_level; 116 ptep = (pte_t *)gstage_pte_page_vaddr(ptep_get(ptep)); 117 ptep = &ptep[gstage_pte_index(addr, current_level)]; 118 } else { 119 ptep = NULL; 120 } 121 } 122 123 return false; 124 } 125 126 static void gstage_remote_tlb_flush(struct kvm *kvm, u32 level, gpa_t addr) 127 { 128 unsigned long order = PAGE_SHIFT; 129 130 if (gstage_level_to_page_order(level, &order)) 131 return; 132 addr &= ~(BIT(order) - 1); 133 134 kvm_riscv_hfence_gvma_vmid_gpa(kvm, -1UL, 0, addr, BIT(order), order); 135 } 136 137 static int gstage_set_pte(struct kvm *kvm, u32 level, 138 struct kvm_mmu_memory_cache *pcache, 139 gpa_t addr, const pte_t *new_pte) 140 { 141 u32 current_level = gstage_pgd_levels - 1; 142 pte_t *next_ptep = (pte_t *)kvm->arch.pgd; 143 pte_t *ptep = &next_ptep[gstage_pte_index(addr, current_level)]; 144 145 if (current_level < level) 146 return -EINVAL; 147 148 while (current_level != level) { 149 if (gstage_pte_leaf(ptep)) 150 return -EEXIST; 151 152 if (!pte_val(ptep_get(ptep))) { 153 if (!pcache) 154 return -ENOMEM; 155 next_ptep = kvm_mmu_memory_cache_alloc(pcache); 156 if (!next_ptep) 157 return -ENOMEM; 158 set_pte(ptep, pfn_pte(PFN_DOWN(__pa(next_ptep)), 159 __pgprot(_PAGE_TABLE))); 160 } else { 161 if (gstage_pte_leaf(ptep)) 162 return -EEXIST; 163 next_ptep = (pte_t *)gstage_pte_page_vaddr(ptep_get(ptep)); 164 } 165 166 current_level--; 167 ptep = &next_ptep[gstage_pte_index(addr, current_level)]; 168 } 169 170 set_pte(ptep, *new_pte); 171 if (gstage_pte_leaf(ptep)) 172 gstage_remote_tlb_flush(kvm, current_level, addr); 173 174 return 0; 175 } 176 177 static int gstage_map_page(struct kvm *kvm, 178 struct kvm_mmu_memory_cache *pcache, 179 gpa_t gpa, phys_addr_t hpa, 180 unsigned long page_size, 181 bool page_rdonly, bool page_exec) 182 { 183 int ret; 184 u32 level = 0; 185 pte_t new_pte; 186 pgprot_t prot; 187 188 ret = gstage_page_size_to_level(page_size, &level); 189 if (ret) 190 return ret; 191 192 /* 193 * A RISC-V implementation can choose to either: 194 * 1) Update 'A' and 'D' PTE bits in hardware 195 * 2) Generate page fault when 'A' and/or 'D' bits are not set 196 * PTE so that software can update these bits. 197 * 198 * We support both options mentioned above. To achieve this, we 199 * always set 'A' and 'D' PTE bits at time of creating G-stage 200 * mapping. To support KVM dirty page logging with both options 201 * mentioned above, we will write-protect G-stage PTEs to track 202 * dirty pages. 203 */ 204 205 if (page_exec) { 206 if (page_rdonly) 207 prot = PAGE_READ_EXEC; 208 else 209 prot = PAGE_WRITE_EXEC; 210 } else { 211 if (page_rdonly) 212 prot = PAGE_READ; 213 else 214 prot = PAGE_WRITE; 215 } 216 new_pte = pfn_pte(PFN_DOWN(hpa), prot); 217 new_pte = pte_mkdirty(new_pte); 218 219 return gstage_set_pte(kvm, level, pcache, gpa, &new_pte); 220 } 221 222 enum gstage_op { 223 GSTAGE_OP_NOP = 0, /* Nothing */ 224 GSTAGE_OP_CLEAR, /* Clear/Unmap */ 225 GSTAGE_OP_WP, /* Write-protect */ 226 }; 227 228 static void gstage_op_pte(struct kvm *kvm, gpa_t addr, 229 pte_t *ptep, u32 ptep_level, enum gstage_op op) 230 { 231 int i, ret; 232 pte_t *next_ptep; 233 u32 next_ptep_level; 234 unsigned long next_page_size, page_size; 235 236 ret = gstage_level_to_page_size(ptep_level, &page_size); 237 if (ret) 238 return; 239 240 BUG_ON(addr & (page_size - 1)); 241 242 if (!pte_val(ptep_get(ptep))) 243 return; 244 245 if (ptep_level && !gstage_pte_leaf(ptep)) { 246 next_ptep = (pte_t *)gstage_pte_page_vaddr(ptep_get(ptep)); 247 next_ptep_level = ptep_level - 1; 248 ret = gstage_level_to_page_size(next_ptep_level, 249 &next_page_size); 250 if (ret) 251 return; 252 253 if (op == GSTAGE_OP_CLEAR) 254 set_pte(ptep, __pte(0)); 255 for (i = 0; i < PTRS_PER_PTE; i++) 256 gstage_op_pte(kvm, addr + i * next_page_size, 257 &next_ptep[i], next_ptep_level, op); 258 if (op == GSTAGE_OP_CLEAR) 259 put_page(virt_to_page(next_ptep)); 260 } else { 261 if (op == GSTAGE_OP_CLEAR) 262 set_pte(ptep, __pte(0)); 263 else if (op == GSTAGE_OP_WP) 264 set_pte(ptep, __pte(pte_val(ptep_get(ptep)) & ~_PAGE_WRITE)); 265 gstage_remote_tlb_flush(kvm, ptep_level, addr); 266 } 267 } 268 269 static void gstage_unmap_range(struct kvm *kvm, gpa_t start, 270 gpa_t size, bool may_block) 271 { 272 int ret; 273 pte_t *ptep; 274 u32 ptep_level; 275 bool found_leaf; 276 unsigned long page_size; 277 gpa_t addr = start, end = start + size; 278 279 while (addr < end) { 280 found_leaf = gstage_get_leaf_entry(kvm, addr, 281 &ptep, &ptep_level); 282 ret = gstage_level_to_page_size(ptep_level, &page_size); 283 if (ret) 284 break; 285 286 if (!found_leaf) 287 goto next; 288 289 if (!(addr & (page_size - 1)) && ((end - addr) >= page_size)) 290 gstage_op_pte(kvm, addr, ptep, 291 ptep_level, GSTAGE_OP_CLEAR); 292 293 next: 294 addr += page_size; 295 296 /* 297 * If the range is too large, release the kvm->mmu_lock 298 * to prevent starvation and lockup detector warnings. 299 */ 300 if (may_block && addr < end) 301 cond_resched_lock(&kvm->mmu_lock); 302 } 303 } 304 305 static void gstage_wp_range(struct kvm *kvm, gpa_t start, gpa_t end) 306 { 307 int ret; 308 pte_t *ptep; 309 u32 ptep_level; 310 bool found_leaf; 311 gpa_t addr = start; 312 unsigned long page_size; 313 314 while (addr < end) { 315 found_leaf = gstage_get_leaf_entry(kvm, addr, 316 &ptep, &ptep_level); 317 ret = gstage_level_to_page_size(ptep_level, &page_size); 318 if (ret) 319 break; 320 321 if (!found_leaf) 322 goto next; 323 324 if (!(addr & (page_size - 1)) && ((end - addr) >= page_size)) 325 gstage_op_pte(kvm, addr, ptep, 326 ptep_level, GSTAGE_OP_WP); 327 328 next: 329 addr += page_size; 330 } 331 } 332 333 static void gstage_wp_memory_region(struct kvm *kvm, int slot) 334 { 335 struct kvm_memslots *slots = kvm_memslots(kvm); 336 struct kvm_memory_slot *memslot = id_to_memslot(slots, slot); 337 phys_addr_t start = memslot->base_gfn << PAGE_SHIFT; 338 phys_addr_t end = (memslot->base_gfn + memslot->npages) << PAGE_SHIFT; 339 340 spin_lock(&kvm->mmu_lock); 341 gstage_wp_range(kvm, start, end); 342 spin_unlock(&kvm->mmu_lock); 343 kvm_flush_remote_tlbs(kvm); 344 } 345 346 int kvm_riscv_gstage_ioremap(struct kvm *kvm, gpa_t gpa, 347 phys_addr_t hpa, unsigned long size, 348 bool writable, bool in_atomic) 349 { 350 pte_t pte; 351 int ret = 0; 352 unsigned long pfn; 353 phys_addr_t addr, end; 354 struct kvm_mmu_memory_cache pcache = { 355 .gfp_custom = (in_atomic) ? GFP_ATOMIC | __GFP_ACCOUNT : 0, 356 .gfp_zero = __GFP_ZERO, 357 }; 358 359 end = (gpa + size + PAGE_SIZE - 1) & PAGE_MASK; 360 pfn = __phys_to_pfn(hpa); 361 362 for (addr = gpa; addr < end; addr += PAGE_SIZE) { 363 pte = pfn_pte(pfn, PAGE_KERNEL_IO); 364 365 if (!writable) 366 pte = pte_wrprotect(pte); 367 368 ret = kvm_mmu_topup_memory_cache(&pcache, gstage_pgd_levels); 369 if (ret) 370 goto out; 371 372 spin_lock(&kvm->mmu_lock); 373 ret = gstage_set_pte(kvm, 0, &pcache, addr, &pte); 374 spin_unlock(&kvm->mmu_lock); 375 if (ret) 376 goto out; 377 378 pfn++; 379 } 380 381 out: 382 kvm_mmu_free_memory_cache(&pcache); 383 return ret; 384 } 385 386 void kvm_riscv_gstage_iounmap(struct kvm *kvm, gpa_t gpa, unsigned long size) 387 { 388 spin_lock(&kvm->mmu_lock); 389 gstage_unmap_range(kvm, gpa, size, false); 390 spin_unlock(&kvm->mmu_lock); 391 } 392 393 void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm, 394 struct kvm_memory_slot *slot, 395 gfn_t gfn_offset, 396 unsigned long mask) 397 { 398 phys_addr_t base_gfn = slot->base_gfn + gfn_offset; 399 phys_addr_t start = (base_gfn + __ffs(mask)) << PAGE_SHIFT; 400 phys_addr_t end = (base_gfn + __fls(mask) + 1) << PAGE_SHIFT; 401 402 gstage_wp_range(kvm, start, end); 403 } 404 405 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 406 { 407 } 408 409 void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free) 410 { 411 } 412 413 void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) 414 { 415 } 416 417 void kvm_arch_flush_shadow_all(struct kvm *kvm) 418 { 419 kvm_riscv_gstage_free_pgd(kvm); 420 } 421 422 void kvm_arch_flush_shadow_memslot(struct kvm *kvm, 423 struct kvm_memory_slot *slot) 424 { 425 gpa_t gpa = slot->base_gfn << PAGE_SHIFT; 426 phys_addr_t size = slot->npages << PAGE_SHIFT; 427 428 spin_lock(&kvm->mmu_lock); 429 gstage_unmap_range(kvm, gpa, size, false); 430 spin_unlock(&kvm->mmu_lock); 431 } 432 433 void kvm_arch_commit_memory_region(struct kvm *kvm, 434 struct kvm_memory_slot *old, 435 const struct kvm_memory_slot *new, 436 enum kvm_mr_change change) 437 { 438 /* 439 * At this point memslot has been committed and there is an 440 * allocated dirty_bitmap[], dirty pages will be tracked while 441 * the memory slot is write protected. 442 */ 443 if (change != KVM_MR_DELETE && new->flags & KVM_MEM_LOG_DIRTY_PAGES) 444 gstage_wp_memory_region(kvm, new->id); 445 } 446 447 int kvm_arch_prepare_memory_region(struct kvm *kvm, 448 const struct kvm_memory_slot *old, 449 struct kvm_memory_slot *new, 450 enum kvm_mr_change change) 451 { 452 hva_t hva, reg_end, size; 453 gpa_t base_gpa; 454 bool writable; 455 int ret = 0; 456 457 if (change != KVM_MR_CREATE && change != KVM_MR_MOVE && 458 change != KVM_MR_FLAGS_ONLY) 459 return 0; 460 461 /* 462 * Prevent userspace from creating a memory region outside of the GPA 463 * space addressable by the KVM guest GPA space. 464 */ 465 if ((new->base_gfn + new->npages) >= 466 (gstage_gpa_size >> PAGE_SHIFT)) 467 return -EFAULT; 468 469 hva = new->userspace_addr; 470 size = new->npages << PAGE_SHIFT; 471 reg_end = hva + size; 472 base_gpa = new->base_gfn << PAGE_SHIFT; 473 writable = !(new->flags & KVM_MEM_READONLY); 474 475 mmap_read_lock(current->mm); 476 477 /* 478 * A memory region could potentially cover multiple VMAs, and 479 * any holes between them, so iterate over all of them to find 480 * out if we can map any of them right now. 481 * 482 * +--------------------------------------------+ 483 * +---------------+----------------+ +----------------+ 484 * | : VMA 1 | VMA 2 | | VMA 3 : | 485 * +---------------+----------------+ +----------------+ 486 * | memory region | 487 * +--------------------------------------------+ 488 */ 489 do { 490 struct vm_area_struct *vma = find_vma(current->mm, hva); 491 hva_t vm_start, vm_end; 492 493 if (!vma || vma->vm_start >= reg_end) 494 break; 495 496 /* 497 * Mapping a read-only VMA is only allowed if the 498 * memory region is configured as read-only. 499 */ 500 if (writable && !(vma->vm_flags & VM_WRITE)) { 501 ret = -EPERM; 502 break; 503 } 504 505 /* Take the intersection of this VMA with the memory region */ 506 vm_start = max(hva, vma->vm_start); 507 vm_end = min(reg_end, vma->vm_end); 508 509 if (vma->vm_flags & VM_PFNMAP) { 510 gpa_t gpa = base_gpa + (vm_start - hva); 511 phys_addr_t pa; 512 513 pa = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT; 514 pa += vm_start - vma->vm_start; 515 516 /* IO region dirty page logging not allowed */ 517 if (new->flags & KVM_MEM_LOG_DIRTY_PAGES) { 518 ret = -EINVAL; 519 goto out; 520 } 521 522 ret = kvm_riscv_gstage_ioremap(kvm, gpa, pa, 523 vm_end - vm_start, 524 writable, false); 525 if (ret) 526 break; 527 } 528 hva = vm_end; 529 } while (hva < reg_end); 530 531 if (change == KVM_MR_FLAGS_ONLY) 532 goto out; 533 534 if (ret) 535 kvm_riscv_gstage_iounmap(kvm, base_gpa, size); 536 537 out: 538 mmap_read_unlock(current->mm); 539 return ret; 540 } 541 542 bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range) 543 { 544 if (!kvm->arch.pgd) 545 return false; 546 547 gstage_unmap_range(kvm, range->start << PAGE_SHIFT, 548 (range->end - range->start) << PAGE_SHIFT, 549 range->may_block); 550 return false; 551 } 552 553 bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range) 554 { 555 int ret; 556 kvm_pfn_t pfn = pte_pfn(range->arg.pte); 557 558 if (!kvm->arch.pgd) 559 return false; 560 561 WARN_ON(range->end - range->start != 1); 562 563 ret = gstage_map_page(kvm, NULL, range->start << PAGE_SHIFT, 564 __pfn_to_phys(pfn), PAGE_SIZE, true, true); 565 if (ret) { 566 kvm_debug("Failed to map G-stage page (error %d)\n", ret); 567 return true; 568 } 569 570 return false; 571 } 572 573 bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) 574 { 575 pte_t *ptep; 576 u32 ptep_level = 0; 577 u64 size = (range->end - range->start) << PAGE_SHIFT; 578 579 if (!kvm->arch.pgd) 580 return false; 581 582 WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); 583 584 if (!gstage_get_leaf_entry(kvm, range->start << PAGE_SHIFT, 585 &ptep, &ptep_level)) 586 return false; 587 588 return ptep_test_and_clear_young(NULL, 0, ptep); 589 } 590 591 bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) 592 { 593 pte_t *ptep; 594 u32 ptep_level = 0; 595 u64 size = (range->end - range->start) << PAGE_SHIFT; 596 597 if (!kvm->arch.pgd) 598 return false; 599 600 WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); 601 602 if (!gstage_get_leaf_entry(kvm, range->start << PAGE_SHIFT, 603 &ptep, &ptep_level)) 604 return false; 605 606 return pte_young(ptep_get(ptep)); 607 } 608 609 int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, 610 struct kvm_memory_slot *memslot, 611 gpa_t gpa, unsigned long hva, bool is_write) 612 { 613 int ret; 614 kvm_pfn_t hfn; 615 bool writable; 616 short vma_pageshift; 617 gfn_t gfn = gpa >> PAGE_SHIFT; 618 struct vm_area_struct *vma; 619 struct kvm *kvm = vcpu->kvm; 620 struct kvm_mmu_memory_cache *pcache = &vcpu->arch.mmu_page_cache; 621 bool logging = (memslot->dirty_bitmap && 622 !(memslot->flags & KVM_MEM_READONLY)) ? true : false; 623 unsigned long vma_pagesize, mmu_seq; 624 625 /* We need minimum second+third level pages */ 626 ret = kvm_mmu_topup_memory_cache(pcache, gstage_pgd_levels); 627 if (ret) { 628 kvm_err("Failed to topup G-stage cache\n"); 629 return ret; 630 } 631 632 mmap_read_lock(current->mm); 633 634 vma = vma_lookup(current->mm, hva); 635 if (unlikely(!vma)) { 636 kvm_err("Failed to find VMA for hva 0x%lx\n", hva); 637 mmap_read_unlock(current->mm); 638 return -EFAULT; 639 } 640 641 if (is_vm_hugetlb_page(vma)) 642 vma_pageshift = huge_page_shift(hstate_vma(vma)); 643 else 644 vma_pageshift = PAGE_SHIFT; 645 vma_pagesize = 1ULL << vma_pageshift; 646 if (logging || (vma->vm_flags & VM_PFNMAP)) 647 vma_pagesize = PAGE_SIZE; 648 649 if (vma_pagesize == PMD_SIZE || vma_pagesize == PUD_SIZE) 650 gfn = (gpa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT; 651 652 /* 653 * Read mmu_invalidate_seq so that KVM can detect if the results of 654 * vma_lookup() or gfn_to_pfn_prot() become stale priort to acquiring 655 * kvm->mmu_lock. 656 * 657 * Rely on mmap_read_unlock() for an implicit smp_rmb(), which pairs 658 * with the smp_wmb() in kvm_mmu_invalidate_end(). 659 */ 660 mmu_seq = kvm->mmu_invalidate_seq; 661 mmap_read_unlock(current->mm); 662 663 if (vma_pagesize != PUD_SIZE && 664 vma_pagesize != PMD_SIZE && 665 vma_pagesize != PAGE_SIZE) { 666 kvm_err("Invalid VMA page size 0x%lx\n", vma_pagesize); 667 return -EFAULT; 668 } 669 670 hfn = gfn_to_pfn_prot(kvm, gfn, is_write, &writable); 671 if (hfn == KVM_PFN_ERR_HWPOISON) { 672 send_sig_mceerr(BUS_MCEERR_AR, (void __user *)hva, 673 vma_pageshift, current); 674 return 0; 675 } 676 if (is_error_noslot_pfn(hfn)) 677 return -EFAULT; 678 679 /* 680 * If logging is active then we allow writable pages only 681 * for write faults. 682 */ 683 if (logging && !is_write) 684 writable = false; 685 686 spin_lock(&kvm->mmu_lock); 687 688 if (mmu_invalidate_retry(kvm, mmu_seq)) 689 goto out_unlock; 690 691 if (writable) { 692 kvm_set_pfn_dirty(hfn); 693 mark_page_dirty(kvm, gfn); 694 ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, 695 vma_pagesize, false, true); 696 } else { 697 ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, 698 vma_pagesize, true, true); 699 } 700 701 if (ret) 702 kvm_err("Failed to map in G-stage\n"); 703 704 out_unlock: 705 spin_unlock(&kvm->mmu_lock); 706 kvm_set_pfn_accessed(hfn); 707 kvm_release_pfn_clean(hfn); 708 return ret; 709 } 710 711 int kvm_riscv_gstage_alloc_pgd(struct kvm *kvm) 712 { 713 struct page *pgd_page; 714 715 if (kvm->arch.pgd != NULL) { 716 kvm_err("kvm_arch already initialized?\n"); 717 return -EINVAL; 718 } 719 720 pgd_page = alloc_pages(GFP_KERNEL | __GFP_ZERO, 721 get_order(gstage_pgd_size)); 722 if (!pgd_page) 723 return -ENOMEM; 724 kvm->arch.pgd = page_to_virt(pgd_page); 725 kvm->arch.pgd_phys = page_to_phys(pgd_page); 726 727 return 0; 728 } 729 730 void kvm_riscv_gstage_free_pgd(struct kvm *kvm) 731 { 732 void *pgd = NULL; 733 734 spin_lock(&kvm->mmu_lock); 735 if (kvm->arch.pgd) { 736 gstage_unmap_range(kvm, 0UL, gstage_gpa_size, false); 737 pgd = READ_ONCE(kvm->arch.pgd); 738 kvm->arch.pgd = NULL; 739 kvm->arch.pgd_phys = 0; 740 } 741 spin_unlock(&kvm->mmu_lock); 742 743 if (pgd) 744 free_pages((unsigned long)pgd, get_order(gstage_pgd_size)); 745 } 746 747 void kvm_riscv_gstage_update_hgatp(struct kvm_vcpu *vcpu) 748 { 749 unsigned long hgatp = gstage_mode; 750 struct kvm_arch *k = &vcpu->kvm->arch; 751 752 hgatp |= (READ_ONCE(k->vmid.vmid) << HGATP_VMID_SHIFT) & HGATP_VMID; 753 hgatp |= (k->pgd_phys >> PAGE_SHIFT) & HGATP_PPN; 754 755 csr_write(CSR_HGATP, hgatp); 756 757 if (!kvm_riscv_gstage_vmid_bits()) 758 kvm_riscv_local_hfence_gvma_all(); 759 } 760 761 void __init kvm_riscv_gstage_mode_detect(void) 762 { 763 #ifdef CONFIG_64BIT 764 /* Try Sv57x4 G-stage mode */ 765 csr_write(CSR_HGATP, HGATP_MODE_SV57X4 << HGATP_MODE_SHIFT); 766 if ((csr_read(CSR_HGATP) >> HGATP_MODE_SHIFT) == HGATP_MODE_SV57X4) { 767 gstage_mode = (HGATP_MODE_SV57X4 << HGATP_MODE_SHIFT); 768 gstage_pgd_levels = 5; 769 goto skip_sv48x4_test; 770 } 771 772 /* Try Sv48x4 G-stage mode */ 773 csr_write(CSR_HGATP, HGATP_MODE_SV48X4 << HGATP_MODE_SHIFT); 774 if ((csr_read(CSR_HGATP) >> HGATP_MODE_SHIFT) == HGATP_MODE_SV48X4) { 775 gstage_mode = (HGATP_MODE_SV48X4 << HGATP_MODE_SHIFT); 776 gstage_pgd_levels = 4; 777 } 778 skip_sv48x4_test: 779 780 csr_write(CSR_HGATP, 0); 781 kvm_riscv_local_hfence_gvma_all(); 782 #endif 783 } 784 785 unsigned long __init kvm_riscv_gstage_mode(void) 786 { 787 return gstage_mode >> HGATP_MODE_SHIFT; 788 } 789 790 int kvm_riscv_gstage_gpa_bits(void) 791 { 792 return gstage_gpa_bits; 793 } 794