arch/powerpc/kvm/book3s_64_mmu

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This source file includes following definitions.
__kvmhv_copy_tofrom_guest_radix
kvmhv_copy_tofrom_guest_radix
kvmhv_copy_from_guest_radix
kvmhv_copy_to_guest_radix
kvmppc_mmu_walk_radix_tree
kvmppc_mmu_radix_translate_table
kvmppc_mmu_radix_xlate
kvmppc_radix_tlbie_page
kvmppc_radix_flush_pwc
kvmppc_radix_update_pte
kvmppc_radix_set_pte_at
kvmppc_pte_alloc
kvmppc_pte_free
kvmppc_pmd_alloc
kvmppc_pmd_free
kvmppc_unmap_pte
kvmppc_unmap_free_pte
kvmppc_unmap_free_pmd
kvmppc_unmap_free_pud
kvmppc_free_pgtable_radix
kvmppc_free_radix
kvmppc_unmap_free_pmd_entry_table
kvmppc_unmap_free_pud_entry_table
kvmppc_create_pte
kvmppc_hv_handle_set_rc
kvmppc_book3s_instantiate_page
kvmppc_book3s_radix_page_fault
kvm_unmap_radix
kvm_age_radix
kvm_test_age_radix
kvm_radix_test_clear_dirty
kvmppc_hv_get_dirty_log_radix
kvmppc_radix_flush_memslot
add_rmmu_ap_encoding
kvmhv_get_rmmu_info
kvmppc_init_vm_radix
pte_ctor
pmd_ctor
debugfs_radix_open
debugfs_radix_release
debugfs_radix_read
debugfs_radix_write
kvmhv_radix_debugfs_init
kvmppc_radix_init
kvmppc_radix_exit
   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 
  15 #include <asm/kvm_ppc.h>
  16 #include <asm/kvm_book3s.h>
  17 #include <asm/page.h>
  18 #include <asm/mmu.h>
  19 #include <asm/pgtable.h>
  20 #include <asm/pgalloc.h>
  21 #include <asm/pte-walk.h>
  22 
  23 /*
  24  * Supported radix tree geometry.
  25  * Like p9, we support either 5 or 9 bits at the first (lowest) level,
  26  * for a page size of 64k or 4k.
  27  */
  28 static int p9_supported_radix_bits[4] = { 5, 9, 9, 13 };
  29 
  30 unsigned long __kvmhv_copy_tofrom_guest_radix(int lpid, int pid,
  31                                               gva_t eaddr, void *to, void *from,
  32                                               unsigned long n)
  33 {
  34         int uninitialized_var(old_pid), old_lpid;
  35         unsigned long quadrant, ret = n;
  36         bool is_load = !!to;
  37 
  38         /* Can't access quadrants 1 or 2 in non-HV mode, call the HV to do it */
  39         if (kvmhv_on_pseries())
  40                 return plpar_hcall_norets(H_COPY_TOFROM_GUEST, lpid, pid, eaddr,
  41                                           __pa(to), __pa(from), n);
  42 
  43         quadrant = 1;
  44         if (!pid)
  45                 quadrant = 2;
  46         if (is_load)
  47                 from = (void *) (eaddr | (quadrant << 62));
  48         else
  49                 to = (void *) (eaddr | (quadrant << 62));
  50 
  51         preempt_disable();
  52 
  53         /* switch the lpid first to avoid running host with unallocated pid */
  54         old_lpid = mfspr(SPRN_LPID);
  55         if (old_lpid != lpid)
  56                 mtspr(SPRN_LPID, lpid);
  57         if (quadrant == 1) {
  58                 old_pid = mfspr(SPRN_PID);
  59                 if (old_pid != pid)
  60                         mtspr(SPRN_PID, pid);
  61         }
  62         isync();
  63 
  64         pagefault_disable();
  65         if (is_load)
  66                 ret = raw_copy_from_user(to, from, n);
  67         else
  68                 ret = raw_copy_to_user(to, from, n);
  69         pagefault_enable();
  70 
  71         /* switch the pid first to avoid running host with unallocated pid */
  72         if (quadrant == 1 && pid != old_pid)
  73                 mtspr(SPRN_PID, old_pid);
  74         if (lpid != old_lpid)
  75                 mtspr(SPRN_LPID, old_lpid);
  76         isync();
  77 
  78         preempt_enable();
  79 
  80         return ret;
  81 }
  82 EXPORT_SYMBOL_GPL(__kvmhv_copy_tofrom_guest_radix);
  83 
  84 static long kvmhv_copy_tofrom_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr,
  85                                           void *to, void *from, unsigned long n)
  86 {
  87         int lpid = vcpu->kvm->arch.lpid;
  88         int pid = vcpu->arch.pid;
  89 
  90         /* This would cause a data segment intr so don't allow the access */
  91         if (eaddr & (0x3FFUL << 52))
  92                 return -EINVAL;
  93 
  94         /* Should we be using the nested lpid */
  95         if (vcpu->arch.nested)
  96                 lpid = vcpu->arch.nested->shadow_lpid;
  97 
  98         /* If accessing quadrant 3 then pid is expected to be 0 */
  99         if (((eaddr >> 62) & 0x3) == 0x3)
 100                 pid = 0;
 101 
 102         eaddr &= ~(0xFFFUL << 52);
 103 
 104         return __kvmhv_copy_tofrom_guest_radix(lpid, pid, eaddr, to, from, n);
 105 }
 106 
 107 long kvmhv_copy_from_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, void *to,
 108                                  unsigned long n)
 109 {
 110         long ret;
 111 
 112         ret = kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, to, NULL, n);
 113         if (ret > 0)
 114                 memset(to + (n - ret), 0, ret);
 115 
 116         return ret;
 117 }
 118 EXPORT_SYMBOL_GPL(kvmhv_copy_from_guest_radix);
 119 
 120 long kvmhv_copy_to_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr, void *from,
 121                                unsigned long n)
 122 {
 123         return kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, NULL, from, n);
 124 }
 125 EXPORT_SYMBOL_GPL(kvmhv_copy_to_guest_radix);
 126 
 127 int kvmppc_mmu_walk_radix_tree(struct kvm_vcpu *vcpu, gva_t eaddr,
 128                                struct kvmppc_pte *gpte, u64 root,
 129                                u64 *pte_ret_p)
 130 {
 131         struct kvm *kvm = vcpu->kvm;
 132         int ret, level, ps;
 133         unsigned long rts, bits, offset, index;
 134         u64 pte, base, gpa;
 135         __be64 rpte;
 136 
 137         rts = ((root & RTS1_MASK) >> (RTS1_SHIFT - 3)) |
 138                 ((root & RTS2_MASK) >> RTS2_SHIFT);
 139         bits = root & RPDS_MASK;
 140         base = root & RPDB_MASK;
 141 
 142         offset = rts + 31;
 143 
 144         /* Current implementations only support 52-bit space */
 145         if (offset != 52)
 146                 return -EINVAL;
 147 
 148         /* Walk each level of the radix tree */
 149         for (level = 3; level >= 0; --level) {
 150                 u64 addr;
 151                 /* Check a valid size */
 152                 if (level && bits != p9_supported_radix_bits[level])
 153                         return -EINVAL;
 154                 if (level == 0 && !(bits == 5 || bits == 9))
 155                         return -EINVAL;
 156                 offset -= bits;
 157                 index = (eaddr >> offset) & ((1UL << bits) - 1);
 158                 /* Check that low bits of page table base are zero */
 159                 if (base & ((1UL << (bits + 3)) - 1))
 160                         return -EINVAL;
 161                 /* Read the entry from guest memory */
 162                 addr = base + (index * sizeof(rpte));
 163                 ret = kvm_read_guest(kvm, addr, &rpte, sizeof(rpte));
 164                 if (ret) {
 165                         if (pte_ret_p)
 166                                 *pte_ret_p = addr;
 167                         return ret;
 168                 }
 169                 pte = __be64_to_cpu(rpte);
 170                 if (!(pte & _PAGE_PRESENT))
 171                         return -ENOENT;
 172                 /* Check if a leaf entry */
 173                 if (pte & _PAGE_PTE)
 174                         break;
 175                 /* Get ready to walk the next level */
 176                 base = pte & RPDB_MASK;
 177                 bits = pte & RPDS_MASK;
 178         }
 179 
 180         /* Need a leaf at lowest level; 512GB pages not supported */
 181         if (level < 0 || level == 3)
 182                 return -EINVAL;
 183 
 184         /* We found a valid leaf PTE */
 185         /* Offset is now log base 2 of the page size */
 186         gpa = pte & 0x01fffffffffff000ul;
 187         if (gpa & ((1ul << offset) - 1))
 188                 return -EINVAL;
 189         gpa |= eaddr & ((1ul << offset) - 1);
 190         for (ps = MMU_PAGE_4K; ps < MMU_PAGE_COUNT; ++ps)
 191                 if (offset == mmu_psize_defs[ps].shift)
 192                         break;
 193         gpte->page_size = ps;
 194         gpte->page_shift = offset;
 195 
 196         gpte->eaddr = eaddr;
 197         gpte->raddr = gpa;
 198 
 199         /* Work out permissions */
 200         gpte->may_read = !!(pte & _PAGE_READ);
 201         gpte->may_write = !!(pte & _PAGE_WRITE);
 202         gpte->may_execute = !!(pte & _PAGE_EXEC);
 203 
 204         gpte->rc = pte & (_PAGE_ACCESSED | _PAGE_DIRTY);
 205 
 206         if (pte_ret_p)
 207                 *pte_ret_p = pte;
 208 
 209         return 0;
 210 }
 211 
 212 /*
 213  * Used to walk a partition or process table radix tree in guest memory
 214  * Note: We exploit the fact that a partition table and a process
 215  * table have the same layout, a partition-scoped page table and a
 216  * process-scoped page table have the same layout, and the 2nd
 217  * doubleword of a partition table entry has the same layout as
 218  * the PTCR register.
 219  */
 220 int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr,
 221                                      struct kvmppc_pte *gpte, u64 table,
 222                                      int table_index, u64 *pte_ret_p)
 223 {
 224         struct kvm *kvm = vcpu->kvm;
 225         int ret;
 226         unsigned long size, ptbl, root;
 227         struct prtb_entry entry;
 228 
 229         if ((table & PRTS_MASK) > 24)
 230                 return -EINVAL;
 231         size = 1ul << ((table & PRTS_MASK) + 12);
 232 
 233         /* Is the table big enough to contain this entry? */
 234         if ((table_index * sizeof(entry)) >= size)
 235                 return -EINVAL;
 236 
 237         /* Read the table to find the root of the radix tree */
 238         ptbl = (table & PRTB_MASK) + (table_index * sizeof(entry));
 239         ret = kvm_read_guest(kvm, ptbl, &entry, sizeof(entry));
 240         if (ret)
 241                 return ret;
 242 
 243         /* Root is stored in the first double word */
 244         root = be64_to_cpu(entry.prtb0);
 245 
 246         return kvmppc_mmu_walk_radix_tree(vcpu, eaddr, gpte, root, pte_ret_p);
 247 }
 248 
 249 int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 250                            struct kvmppc_pte *gpte, bool data, bool iswrite)
 251 {
 252         u32 pid;
 253         u64 pte;
 254         int ret;
 255 
 256         /* Work out effective PID */
 257         switch (eaddr >> 62) {
 258         case 0:
 259                 pid = vcpu->arch.pid;
 260                 break;
 261         case 3:
 262                 pid = 0;
 263                 break;
 264         default:
 265                 return -EINVAL;
 266         }
 267 
 268         ret = kvmppc_mmu_radix_translate_table(vcpu, eaddr, gpte,
 269                                 vcpu->kvm->arch.process_table, pid, &pte);
 270         if (ret)
 271                 return ret;
 272 
 273         /* Check privilege (applies only to process scoped translations) */
 274         if (kvmppc_get_msr(vcpu) & MSR_PR) {
 275                 if (pte & _PAGE_PRIVILEGED) {
 276                         gpte->may_read = 0;
 277                         gpte->may_write = 0;
 278                         gpte->may_execute = 0;
 279                 }
 280         } else {
 281                 if (!(pte & _PAGE_PRIVILEGED)) {
 282                         /* Check AMR/IAMR to see if strict mode is in force */
 283                         if (vcpu->arch.amr & (1ul << 62))
 284                                 gpte->may_read = 0;
 285                         if (vcpu->arch.amr & (1ul << 63))
 286                                 gpte->may_write = 0;
 287                         if (vcpu->arch.iamr & (1ul << 62))
 288                                 gpte->may_execute = 0;
 289                 }
 290         }
 291 
 292         return 0;
 293 }
 294 
 295 void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr,
 296                              unsigned int pshift, unsigned int lpid)
 297 {
 298         unsigned long psize = PAGE_SIZE;
 299         int psi;
 300         long rc;
 301         unsigned long rb;
 302 
 303         if (pshift)
 304                 psize = 1UL << pshift;
 305         else
 306                 pshift = PAGE_SHIFT;
 307 
 308         addr &= ~(psize - 1);
 309 
 310         if (!kvmhv_on_pseries()) {
 311                 radix__flush_tlb_lpid_page(lpid, addr, psize);
 312                 return;
 313         }
 314 
 315         psi = shift_to_mmu_psize(pshift);
 316         rb = addr | (mmu_get_ap(psi) << PPC_BITLSHIFT(58));
 317         rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(0, 0, 1),
 318                                 lpid, rb);
 319         if (rc)
 320                 pr_err("KVM: TLB page invalidation hcall failed, rc=%ld\n", rc);
 321 }
 322 
 323 static void kvmppc_radix_flush_pwc(struct kvm *kvm, unsigned int lpid)
 324 {
 325         long rc;
 326 
 327         if (!kvmhv_on_pseries()) {
 328                 radix__flush_pwc_lpid(lpid);
 329                 return;
 330         }
 331 
 332         rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(1, 0, 1),
 333                                 lpid, TLBIEL_INVAL_SET_LPID);
 334         if (rc)
 335                 pr_err("KVM: TLB PWC invalidation hcall failed, rc=%ld\n", rc);
 336 }
 337 
 338 static unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep,
 339                                       unsigned long clr, unsigned long set,
 340                                       unsigned long addr, unsigned int shift)
 341 {
 342         return __radix_pte_update(ptep, clr, set);
 343 }
 344 
 345 void kvmppc_radix_set_pte_at(struct kvm *kvm, unsigned long addr,
 346                              pte_t *ptep, pte_t pte)
 347 {
 348         radix__set_pte_at(kvm->mm, addr, ptep, pte, 0);
 349 }
 350 
 351 static struct kmem_cache *kvm_pte_cache;
 352 static struct kmem_cache *kvm_pmd_cache;
 353 
 354 static pte_t *kvmppc_pte_alloc(void)
 355 {
 356         return kmem_cache_alloc(kvm_pte_cache, GFP_KERNEL);
 357 }
 358 
 359 static void kvmppc_pte_free(pte_t *ptep)
 360 {
 361         kmem_cache_free(kvm_pte_cache, ptep);
 362 }
 363 
 364 static pmd_t *kvmppc_pmd_alloc(void)
 365 {
 366         return kmem_cache_alloc(kvm_pmd_cache, GFP_KERNEL);
 367 }
 368 
 369 static void kvmppc_pmd_free(pmd_t *pmdp)
 370 {
 371         kmem_cache_free(kvm_pmd_cache, pmdp);
 372 }
 373 
 374 /* Called with kvm->mmu_lock held */
 375 void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa,
 376                       unsigned int shift,
 377                       const struct kvm_memory_slot *memslot,
 378                       unsigned int lpid)
 379 
 380 {
 381         unsigned long old;
 382         unsigned long gfn = gpa >> PAGE_SHIFT;
 383         unsigned long page_size = PAGE_SIZE;
 384         unsigned long hpa;
 385 
 386         old = kvmppc_radix_update_pte(kvm, pte, ~0UL, 0, gpa, shift);
 387         kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid);
 388 
 389         /* The following only applies to L1 entries */
 390         if (lpid != kvm->arch.lpid)
 391                 return;
 392 
 393         if (!memslot) {
 394                 memslot = gfn_to_memslot(kvm, gfn);
 395                 if (!memslot)
 396                         return;
 397         }
 398         if (shift) { /* 1GB or 2MB page */
 399                 page_size = 1ul << shift;
 400                 if (shift == PMD_SHIFT)
 401                         kvm->stat.num_2M_pages--;
 402                 else if (shift == PUD_SHIFT)
 403                         kvm->stat.num_1G_pages--;
 404         }
 405 
 406         gpa &= ~(page_size - 1);
 407         hpa = old & PTE_RPN_MASK;
 408         kvmhv_remove_nest_rmap_range(kvm, memslot, gpa, hpa, page_size);
 409 
 410         if ((old & _PAGE_DIRTY) && memslot->dirty_bitmap)
 411                 kvmppc_update_dirty_map(memslot, gfn, page_size);
 412 }
 413 
 414 /*
 415  * kvmppc_free_p?d are used to free existing page tables, and recursively
 416  * descend and clear and free children.
 417  * Callers are responsible for flushing the PWC.
 418  *
 419  * When page tables are being unmapped/freed as part of page fault path
 420  * (full == false), ptes are not expected. There is code to unmap them
 421  * and emit a warning if encountered, but there may already be data
 422  * corruption due to the unexpected mappings.
 423  */
 424 static void kvmppc_unmap_free_pte(struct kvm *kvm, pte_t *pte, bool full,
 425                                   unsigned int lpid)
 426 {
 427         if (full) {
 428                 memset(pte, 0, sizeof(long) << PTE_INDEX_SIZE);
 429         } else {
 430                 pte_t *p = pte;
 431                 unsigned long it;
 432 
 433                 for (it = 0; it < PTRS_PER_PTE; ++it, ++p) {
 434                         if (pte_val(*p) == 0)
 435                                 continue;
 436                         WARN_ON_ONCE(1);
 437                         kvmppc_unmap_pte(kvm, p,
 438                                          pte_pfn(*p) << PAGE_SHIFT,
 439                                          PAGE_SHIFT, NULL, lpid);
 440                 }
 441         }
 442 
 443         kvmppc_pte_free(pte);
 444 }
 445 
 446 static void kvmppc_unmap_free_pmd(struct kvm *kvm, pmd_t *pmd, bool full,
 447                                   unsigned int lpid)
 448 {
 449         unsigned long im;
 450         pmd_t *p = pmd;
 451 
 452         for (im = 0; im < PTRS_PER_PMD; ++im, ++p) {
 453                 if (!pmd_present(*p))
 454                         continue;
 455                 if (pmd_is_leaf(*p)) {
 456                         if (full) {
 457                                 pmd_clear(p);
 458                         } else {
 459                                 WARN_ON_ONCE(1);
 460                                 kvmppc_unmap_pte(kvm, (pte_t *)p,
 461                                          pte_pfn(*(pte_t *)p) << PAGE_SHIFT,
 462                                          PMD_SHIFT, NULL, lpid);
 463                         }
 464                 } else {
 465                         pte_t *pte;
 466 
 467                         pte = pte_offset_map(p, 0);
 468                         kvmppc_unmap_free_pte(kvm, pte, full, lpid);
 469                         pmd_clear(p);
 470                 }
 471         }
 472         kvmppc_pmd_free(pmd);
 473 }
 474 
 475 static void kvmppc_unmap_free_pud(struct kvm *kvm, pud_t *pud,
 476                                   unsigned int lpid)
 477 {
 478         unsigned long iu;
 479         pud_t *p = pud;
 480 
 481         for (iu = 0; iu < PTRS_PER_PUD; ++iu, ++p) {
 482                 if (!pud_present(*p))
 483                         continue;
 484                 if (pud_is_leaf(*p)) {
 485                         pud_clear(p);
 486                 } else {
 487                         pmd_t *pmd;
 488 
 489                         pmd = pmd_offset(p, 0);
 490                         kvmppc_unmap_free_pmd(kvm, pmd, true, lpid);
 491                         pud_clear(p);
 492                 }
 493         }
 494         pud_free(kvm->mm, pud);
 495 }
 496 
 497 void kvmppc_free_pgtable_radix(struct kvm *kvm, pgd_t *pgd, unsigned int lpid)
 498 {
 499         unsigned long ig;
 500 
 501         for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) {
 502                 pud_t *pud;
 503 
 504                 if (!pgd_present(*pgd))
 505                         continue;
 506                 pud = pud_offset(pgd, 0);
 507                 kvmppc_unmap_free_pud(kvm, pud, lpid);
 508                 pgd_clear(pgd);
 509         }
 510 }
 511 
 512 void kvmppc_free_radix(struct kvm *kvm)
 513 {
 514         if (kvm->arch.pgtable) {
 515                 kvmppc_free_pgtable_radix(kvm, kvm->arch.pgtable,
 516                                           kvm->arch.lpid);
 517                 pgd_free(kvm->mm, kvm->arch.pgtable);
 518                 kvm->arch.pgtable = NULL;
 519         }
 520 }
 521 
 522 static void kvmppc_unmap_free_pmd_entry_table(struct kvm *kvm, pmd_t *pmd,
 523                                         unsigned long gpa, unsigned int lpid)
 524 {
 525         pte_t *pte = pte_offset_kernel(pmd, 0);
 526 
 527         /*
 528          * Clearing the pmd entry then flushing the PWC ensures that the pte
 529          * page no longer be cached by the MMU, so can be freed without
 530          * flushing the PWC again.
 531          */
 532         pmd_clear(pmd);
 533         kvmppc_radix_flush_pwc(kvm, lpid);
 534 
 535         kvmppc_unmap_free_pte(kvm, pte, false, lpid);
 536 }
 537 
 538 static void kvmppc_unmap_free_pud_entry_table(struct kvm *kvm, pud_t *pud,
 539                                         unsigned long gpa, unsigned int lpid)
 540 {
 541         pmd_t *pmd = pmd_offset(pud, 0);
 542 
 543         /*
 544          * Clearing the pud entry then flushing the PWC ensures that the pmd
 545          * page and any children pte pages will no longer be cached by the MMU,
 546          * so can be freed without flushing the PWC again.
 547          */
 548         pud_clear(pud);
 549         kvmppc_radix_flush_pwc(kvm, lpid);
 550 
 551         kvmppc_unmap_free_pmd(kvm, pmd, false, lpid);
 552 }
 553 
 554 /*
 555  * There are a number of bits which may differ between different faults to
 556  * the same partition scope entry. RC bits, in the course of cleaning and
 557  * aging. And the write bit can change, either the access could have been
 558  * upgraded, or a read fault could happen concurrently with a write fault
 559  * that sets those bits first.
 560  */
 561 #define PTE_BITS_MUST_MATCH (~(_PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED))
 562 
 563 int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
 564                       unsigned long gpa, unsigned int level,
 565                       unsigned long mmu_seq, unsigned int lpid,
 566                       unsigned long *rmapp, struct rmap_nested **n_rmap)
 567 {
 568         pgd_t *pgd;
 569         pud_t *pud, *new_pud = NULL;
 570         pmd_t *pmd, *new_pmd = NULL;
 571         pte_t *ptep, *new_ptep = NULL;
 572         int ret;
 573 
 574         /* Traverse the guest's 2nd-level tree, allocate new levels needed */
 575         pgd = pgtable + pgd_index(gpa);
 576         pud = NULL;
 577         if (pgd_present(*pgd))
 578                 pud = pud_offset(pgd, gpa);
 579         else
 580                 new_pud = pud_alloc_one(kvm->mm, gpa);
 581 
 582         pmd = NULL;
 583         if (pud && pud_present(*pud) && !pud_is_leaf(*pud))
 584                 pmd = pmd_offset(pud, gpa);
 585         else if (level <= 1)
 586                 new_pmd = kvmppc_pmd_alloc();
 587 
 588         if (level == 0 && !(pmd && pmd_present(*pmd) && !pmd_is_leaf(*pmd)))
 589                 new_ptep = kvmppc_pte_alloc();
 590 
 591         /* Check if we might have been invalidated; let the guest retry if so */
 592         spin_lock(&kvm->mmu_lock);
 593         ret = -EAGAIN;
 594         if (mmu_notifier_retry(kvm, mmu_seq))
 595                 goto out_unlock;
 596 
 597         /* Now traverse again under the lock and change the tree */
 598         ret = -ENOMEM;
 599         if (pgd_none(*pgd)) {
 600                 if (!new_pud)
 601                         goto out_unlock;
 602                 pgd_populate(kvm->mm, pgd, new_pud);
 603                 new_pud = NULL;
 604         }
 605         pud = pud_offset(pgd, gpa);
 606         if (pud_is_leaf(*pud)) {
 607                 unsigned long hgpa = gpa & PUD_MASK;
 608 
 609                 /* Check if we raced and someone else has set the same thing */
 610                 if (level == 2) {
 611                         if (pud_raw(*pud) == pte_raw(pte)) {
 612                                 ret = 0;
 613                                 goto out_unlock;
 614                         }
 615                         /* Valid 1GB page here already, add our extra bits */
 616                         WARN_ON_ONCE((pud_val(*pud) ^ pte_val(pte)) &
 617                                                         PTE_BITS_MUST_MATCH);
 618                         kvmppc_radix_update_pte(kvm, (pte_t *)pud,
 619                                               0, pte_val(pte), hgpa, PUD_SHIFT);
 620                         ret = 0;
 621                         goto out_unlock;
 622                 }
 623                 /*
 624                  * If we raced with another CPU which has just put
 625                  * a 1GB pte in after we saw a pmd page, try again.
 626                  */
 627                 if (!new_pmd) {
 628                         ret = -EAGAIN;
 629                         goto out_unlock;
 630                 }
 631                 /* Valid 1GB page here already, remove it */
 632                 kvmppc_unmap_pte(kvm, (pte_t *)pud, hgpa, PUD_SHIFT, NULL,
 633                                  lpid);
 634         }
 635         if (level == 2) {
 636                 if (!pud_none(*pud)) {
 637                         /*
 638                          * There's a page table page here, but we wanted to
 639                          * install a large page, so remove and free the page
 640                          * table page.
 641                          */
 642                         kvmppc_unmap_free_pud_entry_table(kvm, pud, gpa, lpid);
 643                 }
 644                 kvmppc_radix_set_pte_at(kvm, gpa, (pte_t *)pud, pte);
 645                 if (rmapp && n_rmap)
 646                         kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap);
 647                 ret = 0;
 648                 goto out_unlock;
 649         }
 650         if (pud_none(*pud)) {
 651                 if (!new_pmd)
 652                         goto out_unlock;
 653                 pud_populate(kvm->mm, pud, new_pmd);
 654                 new_pmd = NULL;
 655         }
 656         pmd = pmd_offset(pud, gpa);
 657         if (pmd_is_leaf(*pmd)) {
 658                 unsigned long lgpa = gpa & PMD_MASK;
 659 
 660                 /* Check if we raced and someone else has set the same thing */
 661                 if (level == 1) {
 662                         if (pmd_raw(*pmd) == pte_raw(pte)) {
 663                                 ret = 0;
 664                                 goto out_unlock;
 665                         }
 666                         /* Valid 2MB page here already, add our extra bits */
 667                         WARN_ON_ONCE((pmd_val(*pmd) ^ pte_val(pte)) &
 668                                                         PTE_BITS_MUST_MATCH);
 669                         kvmppc_radix_update_pte(kvm, pmdp_ptep(pmd),
 670                                         0, pte_val(pte), lgpa, PMD_SHIFT);
 671                         ret = 0;
 672                         goto out_unlock;
 673                 }
 674 
 675                 /*
 676                  * If we raced with another CPU which has just put
 677                  * a 2MB pte in after we saw a pte page, try again.
 678                  */
 679                 if (!new_ptep) {
 680                         ret = -EAGAIN;
 681                         goto out_unlock;
 682                 }
 683                 /* Valid 2MB page here already, remove it */
 684                 kvmppc_unmap_pte(kvm, pmdp_ptep(pmd), lgpa, PMD_SHIFT, NULL,
 685                                  lpid);
 686         }
 687         if (level == 1) {
 688                 if (!pmd_none(*pmd)) {
 689                         /*
 690                          * There's a page table page here, but we wanted to
 691                          * install a large page, so remove and free the page
 692                          * table page.
 693                          */
 694                         kvmppc_unmap_free_pmd_entry_table(kvm, pmd, gpa, lpid);
 695                 }
 696                 kvmppc_radix_set_pte_at(kvm, gpa, pmdp_ptep(pmd), pte);
 697                 if (rmapp && n_rmap)
 698                         kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap);
 699                 ret = 0;
 700                 goto out_unlock;
 701         }
 702         if (pmd_none(*pmd)) {
 703                 if (!new_ptep)
 704                         goto out_unlock;
 705                 pmd_populate(kvm->mm, pmd, new_ptep);
 706                 new_ptep = NULL;
 707         }
 708         ptep = pte_offset_kernel(pmd, gpa);
 709         if (pte_present(*ptep)) {
 710                 /* Check if someone else set the same thing */
 711                 if (pte_raw(*ptep) == pte_raw(pte)) {
 712                         ret = 0;
 713                         goto out_unlock;
 714                 }
 715                 /* Valid page here already, add our extra bits */
 716                 WARN_ON_ONCE((pte_val(*ptep) ^ pte_val(pte)) &
 717                                                         PTE_BITS_MUST_MATCH);
 718                 kvmppc_radix_update_pte(kvm, ptep, 0, pte_val(pte), gpa, 0);
 719                 ret = 0;
 720                 goto out_unlock;
 721         }
 722         kvmppc_radix_set_pte_at(kvm, gpa, ptep, pte);
 723         if (rmapp && n_rmap)
 724                 kvmhv_insert_nest_rmap(kvm, rmapp, n_rmap);
 725         ret = 0;
 726 
 727  out_unlock:
 728         spin_unlock(&kvm->mmu_lock);
 729         if (new_pud)
 730                 pud_free(kvm->mm, new_pud);
 731         if (new_pmd)
 732                 kvmppc_pmd_free(new_pmd);
 733         if (new_ptep)
 734                 kvmppc_pte_free(new_ptep);
 735         return ret;
 736 }
 737 
 738 bool kvmppc_hv_handle_set_rc(struct kvm *kvm, pgd_t *pgtable, bool writing,
 739                              unsigned long gpa, unsigned int lpid)
 740 {
 741         unsigned long pgflags;
 742         unsigned int shift;
 743         pte_t *ptep;
 744 
 745         /*
 746          * Need to set an R or C bit in the 2nd-level tables;
 747          * since we are just helping out the hardware here,
 748          * it is sufficient to do what the hardware does.
 749          */
 750         pgflags = _PAGE_ACCESSED;
 751         if (writing)
 752                 pgflags |= _PAGE_DIRTY;
 753         /*
 754          * We are walking the secondary (partition-scoped) page table here.
 755          * We can do this without disabling irq because the Linux MM
 756          * subsystem doesn't do THP splits and collapses on this tree.
 757          */
 758         ptep = __find_linux_pte(pgtable, gpa, NULL, &shift);
 759         if (ptep && pte_present(*ptep) && (!writing || pte_write(*ptep))) {
 760                 kvmppc_radix_update_pte(kvm, ptep, 0, pgflags, gpa, shift);
 761                 return true;
 762         }
 763         return false;
 764 }
 765 
 766 int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu,
 767                                    unsigned long gpa,
 768                                    struct kvm_memory_slot *memslot,
 769                                    bool writing, bool kvm_ro,
 770                                    pte_t *inserted_pte, unsigned int *levelp)
 771 {
 772         struct kvm *kvm = vcpu->kvm;
 773         struct page *page = NULL;
 774         unsigned long mmu_seq;
 775         unsigned long hva, gfn = gpa >> PAGE_SHIFT;
 776         bool upgrade_write = false;
 777         bool *upgrade_p = &upgrade_write;
 778         pte_t pte, *ptep;
 779         unsigned int shift, level;
 780         int ret;
 781         bool large_enable;
 782 
 783         /* used to check for invalidations in progress */
 784         mmu_seq = kvm->mmu_notifier_seq;
 785         smp_rmb();
 786 
 787         /*
 788          * Do a fast check first, since __gfn_to_pfn_memslot doesn't
 789          * do it with !atomic && !async, which is how we call it.
 790          * We always ask for write permission since the common case
 791          * is that the page is writable.
 792          */
 793         hva = gfn_to_hva_memslot(memslot, gfn);
 794         if (!kvm_ro && __get_user_pages_fast(hva, 1, 1, &page) == 1) {
 795                 upgrade_write = true;
 796         } else {
 797                 unsigned long pfn;
 798 
 799                 /* Call KVM generic code to do the slow-path check */
 800                 pfn = __gfn_to_pfn_memslot(memslot, gfn, false, NULL,
 801                                            writing, upgrade_p);
 802                 if (is_error_noslot_pfn(pfn))
 803                         return -EFAULT;
 804                 page = NULL;
 805                 if (pfn_valid(pfn)) {
 806                         page = pfn_to_page(pfn);
 807                         if (PageReserved(page))
 808                                 page = NULL;
 809                 }
 810         }
 811 
 812         /*
 813          * Read the PTE from the process' radix tree and use that
 814          * so we get the shift and attribute bits.
 815          */
 816         local_irq_disable();
 817         ptep = __find_linux_pte(vcpu->arch.pgdir, hva, NULL, &shift);
 818         /*
 819          * If the PTE disappeared temporarily due to a THP
 820          * collapse, just return and let the guest try again.
 821          */
 822         if (!ptep) {
 823                 local_irq_enable();
 824                 if (page)
 825                         put_page(page);
 826                 return RESUME_GUEST;
 827         }
 828         pte = *ptep;
 829         local_irq_enable();
 830 
 831         /* If we're logging dirty pages, always map single pages */
 832         large_enable = !(memslot->flags & KVM_MEM_LOG_DIRTY_PAGES);
 833 
 834         /* Get pte level from shift/size */
 835         if (large_enable && shift == PUD_SHIFT &&
 836             (gpa & (PUD_SIZE - PAGE_SIZE)) ==
 837             (hva & (PUD_SIZE - PAGE_SIZE))) {
 838                 level = 2;
 839         } else if (large_enable && shift == PMD_SHIFT &&
 840                    (gpa & (PMD_SIZE - PAGE_SIZE)) ==
 841                    (hva & (PMD_SIZE - PAGE_SIZE))) {
 842                 level = 1;
 843         } else {
 844                 level = 0;
 845                 if (shift > PAGE_SHIFT) {
 846                         /*
 847                          * If the pte maps more than one page, bring over
 848                          * bits from the virtual address to get the real
 849                          * address of the specific single page we want.
 850                          */
 851                         unsigned long rpnmask = (1ul << shift) - PAGE_SIZE;
 852                         pte = __pte(pte_val(pte) | (hva & rpnmask));
 853                 }
 854         }
 855 
 856         pte = __pte(pte_val(pte) | _PAGE_EXEC | _PAGE_ACCESSED);
 857         if (writing || upgrade_write) {
 858                 if (pte_val(pte) & _PAGE_WRITE)
 859                         pte = __pte(pte_val(pte) | _PAGE_DIRTY);
 860         } else {
 861                 pte = __pte(pte_val(pte) & ~(_PAGE_WRITE | _PAGE_DIRTY));
 862         }
 863 
 864         /* Allocate space in the tree and write the PTE */
 865         ret = kvmppc_create_pte(kvm, kvm->arch.pgtable, pte, gpa, level,
 866                                 mmu_seq, kvm->arch.lpid, NULL, NULL);
 867         if (inserted_pte)
 868                 *inserted_pte = pte;
 869         if (levelp)
 870                 *levelp = level;
 871 
 872         if (page) {
 873                 if (!ret && (pte_val(pte) & _PAGE_WRITE))
 874                         set_page_dirty_lock(page);
 875                 put_page(page);
 876         }
 877 
 878         /* Increment number of large pages if we (successfully) inserted one */
 879         if (!ret) {
 880                 if (level == 1)
 881                         kvm->stat.num_2M_pages++;
 882                 else if (level == 2)
 883                         kvm->stat.num_1G_pages++;
 884         }
 885 
 886         return ret;
 887 }
 888 
 889 int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 890                                    unsigned long ea, unsigned long dsisr)
 891 {
 892         struct kvm *kvm = vcpu->kvm;
 893         unsigned long gpa, gfn;
 894         struct kvm_memory_slot *memslot;
 895         long ret;
 896         bool writing = !!(dsisr & DSISR_ISSTORE);
 897         bool kvm_ro = false;
 898 
 899         /* Check for unusual errors */
 900         if (dsisr & DSISR_UNSUPP_MMU) {
 901                 pr_err("KVM: Got unsupported MMU fault\n");
 902                 return -EFAULT;
 903         }
 904         if (dsisr & DSISR_BADACCESS) {
 905                 /* Reflect to the guest as DSI */
 906                 pr_err("KVM: Got radix HV page fault with DSISR=%lx\n", dsisr);
 907                 kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
 908                 return RESUME_GUEST;
 909         }
 910 
 911         /* Translate the logical address */
 912         gpa = vcpu->arch.fault_gpa & ~0xfffUL;
 913         gpa &= ~0xF000000000000000ul;
 914         gfn = gpa >> PAGE_SHIFT;
 915         if (!(dsisr & DSISR_PRTABLE_FAULT))
 916                 gpa |= ea & 0xfff;
 917 
 918         /* Get the corresponding memslot */
 919         memslot = gfn_to_memslot(kvm, gfn);
 920 
 921         /* No memslot means it's an emulated MMIO region */
 922         if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
 923                 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS |
 924                              DSISR_SET_RC)) {
 925                         /*
 926                          * Bad address in guest page table tree, or other
 927                          * unusual error - reflect it to the guest as DSI.
 928                          */
 929                         kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
 930                         return RESUME_GUEST;
 931                 }
 932                 return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea, writing);
 933         }
 934 
 935         if (memslot->flags & KVM_MEM_READONLY) {
 936                 if (writing) {
 937                         /* give the guest a DSI */
 938                         kvmppc_core_queue_data_storage(vcpu, ea, DSISR_ISSTORE |
 939                                                        DSISR_PROTFAULT);
 940                         return RESUME_GUEST;
 941                 }
 942                 kvm_ro = true;
 943         }
 944 
 945         /* Failed to set the reference/change bits */
 946         if (dsisr & DSISR_SET_RC) {
 947                 spin_lock(&kvm->mmu_lock);
 948                 if (kvmppc_hv_handle_set_rc(kvm, kvm->arch.pgtable,
 949                                             writing, gpa, kvm->arch.lpid))
 950                         dsisr &= ~DSISR_SET_RC;
 951                 spin_unlock(&kvm->mmu_lock);
 952 
 953                 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE |
 954                                DSISR_PROTFAULT | DSISR_SET_RC)))
 955                         return RESUME_GUEST;
 956         }
 957 
 958         /* Try to insert a pte */
 959         ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot, writing,
 960                                              kvm_ro, NULL, NULL);
 961 
 962         if (ret == 0 || ret == -EAGAIN)
 963                 ret = RESUME_GUEST;
 964         return ret;
 965 }
 966 
 967 /* Called with kvm->mmu_lock held */
 968 int kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
 969                     unsigned long gfn)
 970 {
 971         pte_t *ptep;
 972         unsigned long gpa = gfn << PAGE_SHIFT;
 973         unsigned int shift;
 974 
 975         ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
 976         if (ptep && pte_present(*ptep))
 977                 kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot,
 978                                  kvm->arch.lpid);
 979         return 0;                               
 980 }
 981 
 982 /* Called with kvm->mmu_lock held */
 983 int kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
 984                   unsigned long gfn)
 985 {
 986         pte_t *ptep;
 987         unsigned long gpa = gfn << PAGE_SHIFT;
 988         unsigned int shift;
 989         int ref = 0;
 990         unsigned long old, *rmapp;
 991 
 992         ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
 993         if (ptep && pte_present(*ptep) && pte_young(*ptep)) {
 994                 old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_ACCESSED, 0,
 995                                               gpa, shift);
 996                 /* XXX need to flush tlb here? */
 997                 /* Also clear bit in ptes in shadow pgtable for nested guests */
 998                 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
 999                 kvmhv_update_nest_rmap_rc_list(kvm, rmapp, _PAGE_ACCESSED, 0,
1000                                                old & PTE_RPN_MASK,
1001                                                1UL << shift);
1002                 ref = 1;
1003         }
1004         return ref;
1005 }
1006 
1007 /* Called with kvm->mmu_lock held */
1008 int kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
1009                        unsigned long gfn)
1010 {
1011         pte_t *ptep;
1012         unsigned long gpa = gfn << PAGE_SHIFT;
1013         unsigned int shift;
1014         int ref = 0;
1015 
1016         ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
1017         if (ptep && pte_present(*ptep) && pte_young(*ptep))
1018                 ref = 1;
1019         return ref;
1020 }
1021 
1022 /* Returns the number of PAGE_SIZE pages that are dirty */
1023 static int kvm_radix_test_clear_dirty(struct kvm *kvm,
1024                                 struct kvm_memory_slot *memslot, int pagenum)
1025 {
1026         unsigned long gfn = memslot->base_gfn + pagenum;
1027         unsigned long gpa = gfn << PAGE_SHIFT;
1028         pte_t *ptep;
1029         unsigned int shift;
1030         int ret = 0;
1031         unsigned long old, *rmapp;
1032 
1033         ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
1034         if (ptep && pte_present(*ptep) && pte_dirty(*ptep)) {
1035                 ret = 1;
1036                 if (shift)
1037                         ret = 1 << (shift - PAGE_SHIFT);
1038                 spin_lock(&kvm->mmu_lock);
1039                 old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_DIRTY, 0,
1040                                               gpa, shift);
1041                 kvmppc_radix_tlbie_page(kvm, gpa, shift, kvm->arch.lpid);
1042                 /* Also clear bit in ptes in shadow pgtable for nested guests */
1043                 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
1044                 kvmhv_update_nest_rmap_rc_list(kvm, rmapp, _PAGE_DIRTY, 0,
1045                                                old & PTE_RPN_MASK,
1046                                                1UL << shift);
1047                 spin_unlock(&kvm->mmu_lock);
1048         }
1049         return ret;
1050 }
1051 
1052 long kvmppc_hv_get_dirty_log_radix(struct kvm *kvm,
1053                         struct kvm_memory_slot *memslot, unsigned long *map)
1054 {
1055         unsigned long i, j;
1056         int npages;
1057 
1058         for (i = 0; i < memslot->npages; i = j) {
1059                 npages = kvm_radix_test_clear_dirty(kvm, memslot, i);
1060 
1061                 /*
1062                  * Note that if npages > 0 then i must be a multiple of npages,
1063                  * since huge pages are only used to back the guest at guest
1064                  * real addresses that are a multiple of their size.
1065                  * Since we have at most one PTE covering any given guest
1066                  * real address, if npages > 1 we can skip to i + npages.
1067                  */
1068                 j = i + 1;
1069                 if (npages) {
1070                         set_dirty_bits(map, i, npages);
1071                         j = i + npages;
1072                 }
1073         }
1074         return 0;
1075 }
1076 
1077 void kvmppc_radix_flush_memslot(struct kvm *kvm,
1078                                 const struct kvm_memory_slot *memslot)
1079 {
1080         unsigned long n;
1081         pte_t *ptep;
1082         unsigned long gpa;
1083         unsigned int shift;
1084 
1085         gpa = memslot->base_gfn << PAGE_SHIFT;
1086         spin_lock(&kvm->mmu_lock);
1087         for (n = memslot->npages; n; --n) {
1088                 ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
1089                 if (ptep && pte_present(*ptep))
1090                         kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot,
1091                                          kvm->arch.lpid);
1092                 gpa += PAGE_SIZE;
1093         }
1094         spin_unlock(&kvm->mmu_lock);
1095 }
1096 
1097 static void add_rmmu_ap_encoding(struct kvm_ppc_rmmu_info *info,
1098                                  int psize, int *indexp)
1099 {
1100         if (!mmu_psize_defs[psize].shift)
1101                 return;
1102         info->ap_encodings[*indexp] = mmu_psize_defs[psize].shift |
1103                 (mmu_psize_defs[psize].ap << 29);
1104         ++(*indexp);
1105 }
1106 
1107 int kvmhv_get_rmmu_info(struct kvm *kvm, struct kvm_ppc_rmmu_info *info)
1108 {
1109         int i;
1110 
1111         if (!radix_enabled())
1112                 return -EINVAL;
1113         memset(info, 0, sizeof(*info));
1114 
1115         /* 4k page size */
1116         info->geometries[0].page_shift = 12;
1117         info->geometries[0].level_bits[0] = 9;
1118         for (i = 1; i < 4; ++i)
1119                 info->geometries[0].level_bits[i] = p9_supported_radix_bits[i];
1120         /* 64k page size */
1121         info->geometries[1].page_shift = 16;
1122         for (i = 0; i < 4; ++i)
1123                 info->geometries[1].level_bits[i] = p9_supported_radix_bits[i];
1124 
1125         i = 0;
1126         add_rmmu_ap_encoding(info, MMU_PAGE_4K, &i);
1127         add_rmmu_ap_encoding(info, MMU_PAGE_64K, &i);
1128         add_rmmu_ap_encoding(info, MMU_PAGE_2M, &i);
1129         add_rmmu_ap_encoding(info, MMU_PAGE_1G, &i);
1130 
1131         return 0;
1132 }
1133 
1134 int kvmppc_init_vm_radix(struct kvm *kvm)
1135 {
1136         kvm->arch.pgtable = pgd_alloc(kvm->mm);
1137         if (!kvm->arch.pgtable)
1138                 return -ENOMEM;
1139         return 0;
1140 }
1141 
1142 static void pte_ctor(void *addr)
1143 {
1144         memset(addr, 0, RADIX_PTE_TABLE_SIZE);
1145 }
1146 
1147 static void pmd_ctor(void *addr)
1148 {
1149         memset(addr, 0, RADIX_PMD_TABLE_SIZE);
1150 }
1151 
1152 struct debugfs_radix_state {
1153         struct kvm      *kvm;
1154         struct mutex    mutex;
1155         unsigned long   gpa;
1156         int             lpid;
1157         int             chars_left;
1158         int             buf_index;
1159         char            buf[128];
1160         u8              hdr;
1161 };
1162 
1163 static int debugfs_radix_open(struct inode *inode, struct file *file)
1164 {
1165         struct kvm *kvm = inode->i_private;
1166         struct debugfs_radix_state *p;
1167 
1168         p = kzalloc(sizeof(*p), GFP_KERNEL);
1169         if (!p)
1170                 return -ENOMEM;
1171 
1172         kvm_get_kvm(kvm);
1173         p->kvm = kvm;
1174         mutex_init(&p->mutex);
1175         file->private_data = p;
1176 
1177         return nonseekable_open(inode, file);
1178 }
1179 
1180 static int debugfs_radix_release(struct inode *inode, struct file *file)
1181 {
1182         struct debugfs_radix_state *p = file->private_data;
1183 
1184         kvm_put_kvm(p->kvm);
1185         kfree(p);
1186         return 0;
1187 }
1188 
1189 static ssize_t debugfs_radix_read(struct file *file, char __user *buf,
1190                                  size_t len, loff_t *ppos)
1191 {
1192         struct debugfs_radix_state *p = file->private_data;
1193         ssize_t ret, r;
1194         unsigned long n;
1195         struct kvm *kvm;
1196         unsigned long gpa;
1197         pgd_t *pgt;
1198         struct kvm_nested_guest *nested;
1199         pgd_t pgd, *pgdp;
1200         pud_t pud, *pudp;
1201         pmd_t pmd, *pmdp;
1202         pte_t *ptep;
1203         int shift;
1204         unsigned long pte;
1205 
1206         kvm = p->kvm;
1207         if (!kvm_is_radix(kvm))
1208                 return 0;
1209 
1210         ret = mutex_lock_interruptible(&p->mutex);
1211         if (ret)
1212                 return ret;
1213 
1214         if (p->chars_left) {
1215                 n = p->chars_left;
1216                 if (n > len)
1217                         n = len;
1218                 r = copy_to_user(buf, p->buf + p->buf_index, n);
1219                 n -= r;
1220                 p->chars_left -= n;
1221                 p->buf_index += n;
1222                 buf += n;
1223                 len -= n;
1224                 ret = n;
1225                 if (r) {
1226                         if (!n)
1227                                 ret = -EFAULT;
1228                         goto out;
1229                 }
1230         }
1231 
1232         gpa = p->gpa;
1233         nested = NULL;
1234         pgt = NULL;
1235         while (len != 0 && p->lpid >= 0) {
1236                 if (gpa >= RADIX_PGTABLE_RANGE) {
1237                         gpa = 0;
1238                         pgt = NULL;
1239                         if (nested) {
1240                                 kvmhv_put_nested(nested);
1241                                 nested = NULL;
1242                         }
1243                         p->lpid = kvmhv_nested_next_lpid(kvm, p->lpid);
1244                         p->hdr = 0;
1245                         if (p->lpid < 0)
1246                                 break;
1247                 }
1248                 if (!pgt) {
1249                         if (p->lpid == 0) {
1250                                 pgt = kvm->arch.pgtable;
1251                         } else {
1252                                 nested = kvmhv_get_nested(kvm, p->lpid, false);
1253                                 if (!nested) {
1254                                         gpa = RADIX_PGTABLE_RANGE;
1255                                         continue;
1256                                 }
1257                                 pgt = nested->shadow_pgtable;
1258                         }
1259                 }
1260                 n = 0;
1261                 if (!p->hdr) {
1262                         if (p->lpid > 0)
1263                                 n = scnprintf(p->buf, sizeof(p->buf),
1264                                               "\nNested LPID %d: ", p->lpid);
1265                         n += scnprintf(p->buf + n, sizeof(p->buf) - n,
1266                                       "pgdir: %lx\n", (unsigned long)pgt);
1267                         p->hdr = 1;
1268                         goto copy;
1269                 }
1270 
1271                 pgdp = pgt + pgd_index(gpa);
1272                 pgd = READ_ONCE(*pgdp);
1273                 if (!(pgd_val(pgd) & _PAGE_PRESENT)) {
1274                         gpa = (gpa & PGDIR_MASK) + PGDIR_SIZE;
1275                         continue;
1276                 }
1277 
1278                 pudp = pud_offset(&pgd, gpa);
1279                 pud = READ_ONCE(*pudp);
1280                 if (!(pud_val(pud) & _PAGE_PRESENT)) {
1281                         gpa = (gpa & PUD_MASK) + PUD_SIZE;
1282                         continue;
1283                 }
1284                 if (pud_val(pud) & _PAGE_PTE) {
1285                         pte = pud_val(pud);
1286                         shift = PUD_SHIFT;
1287                         goto leaf;
1288                 }
1289 
1290                 pmdp = pmd_offset(&pud, gpa);
1291                 pmd = READ_ONCE(*pmdp);
1292                 if (!(pmd_val(pmd) & _PAGE_PRESENT)) {
1293                         gpa = (gpa & PMD_MASK) + PMD_SIZE;
1294                         continue;
1295                 }
1296                 if (pmd_val(pmd) & _PAGE_PTE) {
1297                         pte = pmd_val(pmd);
1298                         shift = PMD_SHIFT;
1299                         goto leaf;
1300                 }
1301 
1302                 ptep = pte_offset_kernel(&pmd, gpa);
1303                 pte = pte_val(READ_ONCE(*ptep));
1304                 if (!(pte & _PAGE_PRESENT)) {
1305                         gpa += PAGE_SIZE;
1306                         continue;
1307                 }
1308                 shift = PAGE_SHIFT;
1309         leaf:
1310                 n = scnprintf(p->buf, sizeof(p->buf),
1311                               " %lx: %lx %d\n", gpa, pte, shift);
1312                 gpa += 1ul << shift;
1313         copy:
1314                 p->chars_left = n;
1315                 if (n > len)
1316                         n = len;
1317                 r = copy_to_user(buf, p->buf, n);
1318                 n -= r;
1319                 p->chars_left -= n;
1320                 p->buf_index = n;
1321                 buf += n;
1322                 len -= n;
1323                 ret += n;
1324                 if (r) {
1325                         if (!ret)
1326                                 ret = -EFAULT;
1327                         break;
1328                 }
1329         }
1330         p->gpa = gpa;
1331         if (nested)
1332                 kvmhv_put_nested(nested);
1333 
1334  out:
1335         mutex_unlock(&p->mutex);
1336         return ret;
1337 }
1338 
1339 static ssize_t debugfs_radix_write(struct file *file, const char __user *buf,
1340                            size_t len, loff_t *ppos)
1341 {
1342         return -EACCES;
1343 }
1344 
1345 static const struct file_operations debugfs_radix_fops = {
1346         .owner   = THIS_MODULE,
1347         .open    = debugfs_radix_open,
1348         .release = debugfs_radix_release,
1349         .read    = debugfs_radix_read,
1350         .write   = debugfs_radix_write,
1351         .llseek  = generic_file_llseek,
1352 };
1353 
1354 void kvmhv_radix_debugfs_init(struct kvm *kvm)
1355 {
1356         kvm->arch.radix_dentry = debugfs_create_file("radix", 0400,
1357                                                      kvm->arch.debugfs_dir, kvm,
1358                                                      &debugfs_radix_fops);
1359 }
1360 
1361 int kvmppc_radix_init(void)
1362 {
1363         unsigned long size = sizeof(void *) << RADIX_PTE_INDEX_SIZE;
1364 
1365         kvm_pte_cache = kmem_cache_create("kvm-pte", size, size, 0, pte_ctor);
1366         if (!kvm_pte_cache)
1367                 return -ENOMEM;
1368 
1369         size = sizeof(void *) << RADIX_PMD_INDEX_SIZE;
1370 
1371         kvm_pmd_cache = kmem_cache_create("kvm-pmd", size, size, 0, pmd_ctor);
1372         if (!kvm_pmd_cache) {
1373                 kmem_cache_destroy(kvm_pte_cache);
1374                 return -ENOMEM;
1375         }
1376 
1377         return 0;
1378 }
1379 
1380 void kvmppc_radix_exit(void)
1381 {
1382         kmem_cache_destroy(kvm_pte_cache);
1383         kmem_cache_destroy(kvm_pmd_cache);
1384 }
/* [<][>][^][v][top][bottom][index][help] */
root/arch/powerpc/kvm/book3s_64_mmu_radix.c

DEFINITIONS
