arch/powerpc/kvm/book3s_64_mmu_hv.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License, version 2, as
   4  * published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * You should have received a copy of the GNU General Public License
  12  * along with this program; if not, write to the Free Software
  13  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  14  *
  15  * Copyright 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
  16  */
  17
  18 #include <linux/types.h>
  19 #include <linux/string.h>
  20 #include <linux/kvm.h>
  21 #include <linux/kvm_host.h>
  22 #include <linux/highmem.h>
  23 #include <linux/gfp.h>
  24 #include <linux/slab.h>
  25 #include <linux/hugetlb.h>
  26 #include <linux/vmalloc.h>
  27 #include <linux/srcu.h>
  28 #include <linux/anon_inodes.h>
  29 #include <linux/file.h>
  30 #include <linux/debugfs.h>
  31
  32 #include <asm/tlbflush.h>
  33 #include <asm/kvm_ppc.h>
  34 #include <asm/kvm_book3s.h>
  35 #include <asm/book3s/64/mmu-hash.h>
  36 #include <asm/hvcall.h>
  37 #include <asm/synch.h>
  38 #include <asm/ppc-opcode.h>
  39 #include <asm/cputable.h>
  40
  41 #include "trace_hv.h"
  42
  43 //#define DEBUG_RESIZE_HPT      1
  44
  45 #ifdef DEBUG_RESIZE_HPT
  46 #define resize_hpt_debug(resize, ...)                           \
  47         do {                                                    \
  48                 printk(KERN_DEBUG "RESIZE HPT %p: ", resize);   \
  49                 printk(__VA_ARGS__);                            \
  50         } while (0)
  51 #else
  52 #define resize_hpt_debug(resize, ...)                           \
  53         do { } while (0)
  54 #endif
  55
  56 static long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags,
  57                                 long pte_index, unsigned long pteh,
  58                                 unsigned long ptel, unsigned long *pte_idx_ret);
  59
  60 struct kvm_resize_hpt {
  61         /* These fields read-only after init */
  62         struct kvm *kvm;
  63         struct work_struct work;
  64         u32 order;
  65
  66         /* These fields protected by kvm->lock */
  67         int error;
  68         bool prepare_done;
  69
  70         /* Private to the work thread, until prepare_done is true,
  71          * then protected by kvm->resize_hpt_sem */
  72         struct kvm_hpt_info hpt;
  73 };
  74
  75 static void kvmppc_rmap_reset(struct kvm *kvm);
  76
  77 int kvmppc_allocate_hpt(struct kvm_hpt_info *info, u32 order)
  78 {
  79         unsigned long hpt = 0;
  80         int cma = 0;
  81         struct page *page = NULL;
  82         struct revmap_entry *rev;
  83         unsigned long npte;
  84
  85         if ((order < PPC_MIN_HPT_ORDER) || (order > PPC_MAX_HPT_ORDER))
  86                 return -EINVAL;
  87
  88         page = kvm_alloc_hpt_cma(1ul << (order - PAGE_SHIFT));
  89         if (page) {
  90                 hpt = (unsigned long)pfn_to_kaddr(page_to_pfn(page));
  91                 memset((void *)hpt, 0, (1ul << order));
  92                 cma = 1;
  93         }
  94
  95         if (!hpt)
  96                 hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL
  97                                        |__GFP_NOWARN, order - PAGE_SHIFT);
  98
  99         if (!hpt)
 100                 return -ENOMEM;
 101
 102         /* HPTEs are 2**4 bytes long */
 103         npte = 1ul << (order - 4);
 104
 105         /* Allocate reverse map array */
 106         rev = vmalloc(sizeof(struct revmap_entry) * npte);
 107         if (!rev) {
 108                 pr_err("kvmppc_allocate_hpt: Couldn't alloc reverse map array\n");
 109                 if (cma)
 110                         kvm_free_hpt_cma(page, 1 << (order - PAGE_SHIFT));
 111                 else
 112                         free_pages(hpt, order - PAGE_SHIFT);
 113                 return -ENOMEM;
 114         }
 115
 116         info->order = order;
 117         info->virt = hpt;
 118         info->cma = cma;
 119         info->rev = rev;
 120
 121         return 0;
 122 }
 123
 124 void kvmppc_set_hpt(struct kvm *kvm, struct kvm_hpt_info *info)
 125 {
 126         atomic64_set(&kvm->arch.mmio_update, 0);
 127         kvm->arch.hpt = *info;
 128         kvm->arch.sdr1 = __pa(info->virt) | (info->order - 18);
 129
 130         pr_debug("KVM guest htab at %lx (order %ld), LPID %x\n",
 131                  info->virt, (long)info->order, kvm->arch.lpid);
 132 }
 133
 134 long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order)
 135 {
 136         long err = -EBUSY;
 137         struct kvm_hpt_info info;
 138
 139         if (kvm_is_radix(kvm))
 140                 return -EINVAL;
 141
 142         mutex_lock(&kvm->lock);
 143         if (kvm->arch.hpte_setup_done) {
 144                 kvm->arch.hpte_setup_done = 0;
 145                 /* order hpte_setup_done vs. vcpus_running */
 146                 smp_mb();
 147                 if (atomic_read(&kvm->arch.vcpus_running)) {
 148                         kvm->arch.hpte_setup_done = 1;
 149                         goto out;
 150                 }
 151         }
 152         if (kvm->arch.hpt.order == order) {
 153                 /* We already have a suitable HPT */
 154
 155                 /* Set the entire HPT to 0, i.e. invalid HPTEs */
 156                 memset((void *)kvm->arch.hpt.virt, 0, 1ul << order);
 157                 /*
 158                  * Reset all the reverse-mapping chains for all memslots
 159                  */
 160                 kvmppc_rmap_reset(kvm);
 161                 /* Ensure that each vcpu will flush its TLB on next entry. */
 162                 cpumask_setall(&kvm->arch.need_tlb_flush);
 163                 err = 0;
 164                 goto out;
 165         }
 166
 167         if (kvm->arch.hpt.virt) {
 168                 kvmppc_free_hpt(&kvm->arch.hpt);
 169                 kvmppc_rmap_reset(kvm);
 170         }
 171
 172         err = kvmppc_allocate_hpt(&info, order);
 173         if (err < 0)
 174                 goto out;
 175         kvmppc_set_hpt(kvm, &info);
 176
 177 out:
 178         mutex_unlock(&kvm->lock);
 179         return err;
 180 }
 181
 182 void kvmppc_free_hpt(struct kvm_hpt_info *info)
 183 {
 184         vfree(info->rev);
 185         if (info->cma)
 186                 kvm_free_hpt_cma(virt_to_page(info->virt),
 187                                  1 << (info->order - PAGE_SHIFT));
 188         else if (info->virt)
 189                 free_pages(info->virt, info->order - PAGE_SHIFT);
 190         info->virt = 0;
 191         info->order = 0;
 192 }
 193
 194 /* Bits in first HPTE dword for pagesize 4k, 64k or 16M */
 195 static inline unsigned long hpte0_pgsize_encoding(unsigned long pgsize)
 196 {
 197         return (pgsize > 0x1000) ? HPTE_V_LARGE : 0;
 198 }
 199
 200 /* Bits in second HPTE dword for pagesize 4k, 64k or 16M */
 201 static inline unsigned long hpte1_pgsize_encoding(unsigned long pgsize)
 202 {
 203         return (pgsize == 0x10000) ? 0x1000 : 0;
 204 }
 205
 206 void kvmppc_map_vrma(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot,
 207                      unsigned long porder)
 208 {
 209         unsigned long i;
 210         unsigned long npages;
 211         unsigned long hp_v, hp_r;
 212         unsigned long addr, hash;
 213         unsigned long psize;
 214         unsigned long hp0, hp1;
 215         unsigned long idx_ret;
 216         long ret;
 217         struct kvm *kvm = vcpu->kvm;
 218
 219         psize = 1ul << porder;
 220         npages = memslot->npages >> (porder - PAGE_SHIFT);
 221
 222         /* VRMA can't be > 1TB */
 223         if (npages > 1ul << (40 - porder))
 224                 npages = 1ul << (40 - porder);
 225         /* Can't use more than 1 HPTE per HPTEG */
 226         if (npages > kvmppc_hpt_mask(&kvm->arch.hpt) + 1)
 227                 npages = kvmppc_hpt_mask(&kvm->arch.hpt) + 1;
 228
 229         hp0 = HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)) |
 230                 HPTE_V_BOLTED | hpte0_pgsize_encoding(psize);
 231         hp1 = hpte1_pgsize_encoding(psize) |
 232                 HPTE_R_R | HPTE_R_C | HPTE_R_M | PP_RWXX;
 233
 234         for (i = 0; i < npages; ++i) {
 235                 addr = i << porder;
 236                 /* can't use hpt_hash since va > 64 bits */
 237                 hash = (i ^ (VRMA_VSID ^ (VRMA_VSID << 25)))
 238                         & kvmppc_hpt_mask(&kvm->arch.hpt);
 239                 /*
 240                  * We assume that the hash table is empty and no
 241                  * vcpus are using it at this stage.  Since we create
 242                  * at most one HPTE per HPTEG, we just assume entry 7
 243                  * is available and use it.
 244                  */
 245                 hash = (hash << 3) + 7;
 246                 hp_v = hp0 | ((addr >> 16) & ~0x7fUL);
 247                 hp_r = hp1 | addr;
 248                 ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, hash, hp_v, hp_r,
 249                                                  &idx_ret);
 250                 if (ret != H_SUCCESS) {
 251                         pr_err("KVM: map_vrma at %lx failed, ret=%ld\n",
 252                                addr, ret);
 253                         break;
 254                 }
 255         }
 256 }
 257
 258 int kvmppc_mmu_hv_init(void)
 259 {
 260         unsigned long host_lpid, rsvd_lpid;
 261
 262         if (!cpu_has_feature(CPU_FTR_HVMODE))
 263                 return -EINVAL;
 264
 265         /* POWER7 has 10-bit LPIDs (12-bit in POWER8) */
 266         host_lpid = mfspr(SPRN_LPID);
 267         rsvd_lpid = LPID_RSVD;
 268
 269         kvmppc_init_lpid(rsvd_lpid + 1);
 270
 271         kvmppc_claim_lpid(host_lpid);
 272         /* rsvd_lpid is reserved for use in partition switching */
 273         kvmppc_claim_lpid(rsvd_lpid);
 274
 275         return 0;
 276 }
 277
 278 static void kvmppc_mmu_book3s_64_hv_reset_msr(struct kvm_vcpu *vcpu)
 279 {
 280         unsigned long msr = vcpu->arch.intr_msr;
 281
 282         /* If transactional, change to suspend mode on IRQ delivery */
 283         if (MSR_TM_TRANSACTIONAL(vcpu->arch.shregs.msr))
 284                 msr |= MSR_TS_S;
 285         else
 286                 msr |= vcpu->arch.shregs.msr & MSR_TS_MASK;
 287         kvmppc_set_msr(vcpu, msr);
 288 }
 289
 290 static long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags,
 291                                 long pte_index, unsigned long pteh,
 292                                 unsigned long ptel, unsigned long *pte_idx_ret)
 293 {
 294         long ret;
 295
 296         /* Protect linux PTE lookup from page table destruction */
 297         rcu_read_lock_sched();  /* this disables preemption too */
 298         ret = kvmppc_do_h_enter(kvm, flags, pte_index, pteh, ptel,
 299                                 current->mm->pgd, false, pte_idx_ret);
 300         rcu_read_unlock_sched();
 301         if (ret == H_TOO_HARD) {
 302                 /* this can't happen */
 303                 pr_err("KVM: Oops, kvmppc_h_enter returned too hard!\n");
 304                 ret = H_RESOURCE;       /* or something */
 305         }
 306         return ret;
 307
 308 }
 309
 310 static struct kvmppc_slb *kvmppc_mmu_book3s_hv_find_slbe(struct kvm_vcpu *vcpu,
 311                                                          gva_t eaddr)
 312 {
 313         u64 mask;
 314         int i;
 315
 316         for (i = 0; i < vcpu->arch.slb_nr; i++) {
 317                 if (!(vcpu->arch.slb[i].orige & SLB_ESID_V))
 318                         continue;
 319
 320                 if (vcpu->arch.slb[i].origv & SLB_VSID_B_1T)
 321                         mask = ESID_MASK_1T;
 322                 else
 323                         mask = ESID_MASK;
 324
 325                 if (((vcpu->arch.slb[i].orige ^ eaddr) & mask) == 0)
 326                         return &vcpu->arch.slb[i];
 327         }
 328         return NULL;
 329 }
 330
 331 static unsigned long kvmppc_mmu_get_real_addr(unsigned long v, unsigned long r,
 332                         unsigned long ea)
 333 {
 334         unsigned long ra_mask;
 335
 336         ra_mask = hpte_page_size(v, r) - 1;
 337         return (r & HPTE_R_RPN & ~ra_mask) | (ea & ra_mask);
 338 }
 339
 340 static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 341                         struct kvmppc_pte *gpte, bool data, bool iswrite)
 342 {
 343         struct kvm *kvm = vcpu->kvm;
 344         struct kvmppc_slb *slbe;
 345         unsigned long slb_v;
 346         unsigned long pp, key;
 347         unsigned long v, orig_v, gr;
 348         __be64 *hptep;
 349         int index;
 350         int virtmode = vcpu->arch.shregs.msr & (data ? MSR_DR : MSR_IR);
 351
 352         /* Get SLB entry */
 353         if (virtmode) {
 354                 slbe = kvmppc_mmu_book3s_hv_find_slbe(vcpu, eaddr);
 355                 if (!slbe)
 356                         return -EINVAL;
 357                 slb_v = slbe->origv;
 358         } else {
 359                 /* real mode access */
 360                 slb_v = vcpu->kvm->arch.vrma_slb_v;
 361         }
 362
 363         preempt_disable();
 364         /* Find the HPTE in the hash table */
 365         index = kvmppc_hv_find_lock_hpte(kvm, eaddr, slb_v,
 366                                          HPTE_V_VALID | HPTE_V_ABSENT);
 367         if (index < 0) {
 368                 preempt_enable();
 369                 return -ENOENT;
 370         }
 371         hptep = (__be64 *)(kvm->arch.hpt.virt + (index << 4));
 372         v = orig_v = be64_to_cpu(hptep[0]) & ~HPTE_V_HVLOCK;
 373         if (cpu_has_feature(CPU_FTR_ARCH_300))
 374                 v = hpte_new_to_old_v(v, be64_to_cpu(hptep[1]));
 375         gr = kvm->arch.hpt.rev[index].guest_rpte;
 376
 377         unlock_hpte(hptep, orig_v);
 378         preempt_enable();
 379
 380         gpte->eaddr = eaddr;
 381         gpte->vpage = ((v & HPTE_V_AVPN) << 4) | ((eaddr >> 12) & 0xfff);
 382
 383         /* Get PP bits and key for permission check */
 384         pp = gr & (HPTE_R_PP0 | HPTE_R_PP);
 385         key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS;
 386         key &= slb_v;
 387
 388         /* Calculate permissions */
 389         gpte->may_read = hpte_read_permission(pp, key);
 390         gpte->may_write = hpte_write_permission(pp, key);
 391         gpte->may_execute = gpte->may_read && !(gr & (HPTE_R_N | HPTE_R_G));
 392
 393         /* Storage key permission check for POWER7 */
 394         if (data && virtmode) {
 395                 int amrfield = hpte_get_skey_perm(gr, vcpu->arch.amr);
 396                 if (amrfield & 1)
 397                         gpte->may_read = 0;
 398                 if (amrfield & 2)
 399                         gpte->may_write = 0;
 400         }
 401
 402         /* Get the guest physical address */
 403         gpte->raddr = kvmppc_mmu_get_real_addr(v, gr, eaddr);
 404         return 0;
 405 }
 406
 407 /*
 408  * Quick test for whether an instruction is a load or a store.
 409  * If the instruction is a load or a store, then this will indicate
 410  * which it is, at least on server processors.  (Embedded processors
 411  * have some external PID instructions that don't follow the rule
 412  * embodied here.)  If the instruction isn't a load or store, then
 413  * this doesn't return anything useful.
 414  */
 415 static int instruction_is_store(unsigned int instr)
 416 {
 417         unsigned int mask;
 418
 419         mask = 0x10000000;
 420         if ((instr & 0xfc000000) == 0x7c000000)
 421                 mask = 0x100;           /* major opcode 31 */
 422         return (instr & mask) != 0;
 423 }
 424
 425 int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu,
 426                            unsigned long gpa, gva_t ea, int is_store)
 427 {
 428         u32 last_inst;
 429
 430         /*
 431          * If we fail, we just return to the guest and try executing it again.
 432          */
 433         if (kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst) !=
 434                 EMULATE_DONE)
 435                 return RESUME_GUEST;
 436
 437         /*
 438          * WARNING: We do not know for sure whether the instruction we just
 439          * read from memory is the same that caused the fault in the first
 440          * place.  If the instruction we read is neither an load or a store,
 441          * then it can't access memory, so we don't need to worry about
 442          * enforcing access permissions.  So, assuming it is a load or
 443          * store, we just check that its direction (load or store) is
 444          * consistent with the original fault, since that's what we
 445          * checked the access permissions against.  If there is a mismatch
 446          * we just return and retry the instruction.
 447          */
 448
 449         if (instruction_is_store(last_inst) != !!is_store)
 450                 return RESUME_GUEST;
 451
 452         /*
 453          * Emulated accesses are emulated by looking at the hash for
 454          * translation once, then performing the access later. The
 455          * translation could be invalidated in the meantime in which
 456          * point performing the subsequent memory access on the old
 457          * physical address could possibly be a security hole for the
 458          * guest (but not the host).
 459          *
 460          * This is less of an issue for MMIO stores since they aren't
 461          * globally visible. It could be an issue for MMIO loads to
 462          * a certain extent but we'll ignore it for now.
 463          */
 464
 465         vcpu->arch.paddr_accessed = gpa;
 466         vcpu->arch.vaddr_accessed = ea;
 467         return kvmppc_emulate_mmio(run, vcpu);
 468 }
 469
 470 int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 471                                 unsigned long ea, unsigned long dsisr)
 472 {
 473         struct kvm *kvm = vcpu->kvm;
 474         unsigned long hpte[3], r;
 475         unsigned long hnow_v, hnow_r;
 476         __be64 *hptep;
 477         unsigned long mmu_seq, psize, pte_size;
 478         unsigned long gpa_base, gfn_base;
 479         unsigned long gpa, gfn, hva, pfn;
 480         struct kvm_memory_slot *memslot;
 481         unsigned long *rmap;
 482         struct revmap_entry *rev;
 483         struct page *page, *pages[1];
 484         long index, ret, npages;
 485         bool is_ci;
 486         unsigned int writing, write_ok;
 487         struct vm_area_struct *vma;
 488         unsigned long rcbits;
 489         long mmio_update;
 490
 491         if (kvm_is_radix(kvm))
 492                 return kvmppc_book3s_radix_page_fault(run, vcpu, ea, dsisr);
 493
 494         /*
 495          * Real-mode code has already searched the HPT and found the
 496          * entry we're interested in.  Lock the entry and check that
 497          * it hasn't changed.  If it has, just return and re-execute the
 498          * instruction.
 499          */
 500         if (ea != vcpu->arch.pgfault_addr)
 501                 return RESUME_GUEST;
 502
 503         if (vcpu->arch.pgfault_cache) {
 504                 mmio_update = atomic64_read(&kvm->arch.mmio_update);
 505                 if (mmio_update == vcpu->arch.pgfault_cache->mmio_update) {
 506                         r = vcpu->arch.pgfault_cache->rpte;
 507                         psize = hpte_page_size(vcpu->arch.pgfault_hpte[0], r);
 508                         gpa_base = r & HPTE_R_RPN & ~(psize - 1);
 509                         gfn_base = gpa_base >> PAGE_SHIFT;
 510                         gpa = gpa_base | (ea & (psize - 1));
 511                         return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea,
 512                                                 dsisr & DSISR_ISSTORE);
 513                 }
 514         }
 515         index = vcpu->arch.pgfault_index;
 516         hptep = (__be64 *)(kvm->arch.hpt.virt + (index << 4));
 517         rev = &kvm->arch.hpt.rev[index];
 518         preempt_disable();
 519         while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
 520                 cpu_relax();
 521         hpte[0] = be64_to_cpu(hptep[0]) & ~HPTE_V_HVLOCK;
 522         hpte[1] = be64_to_cpu(hptep[1]);
 523         hpte[2] = r = rev->guest_rpte;
 524         unlock_hpte(hptep, hpte[0]);
 525         preempt_enable();
 526
 527         if (cpu_has_feature(CPU_FTR_ARCH_300)) {
 528                 hpte[0] = hpte_new_to_old_v(hpte[0], hpte[1]);
 529                 hpte[1] = hpte_new_to_old_r(hpte[1]);
 530         }
 531         if (hpte[0] != vcpu->arch.pgfault_hpte[0] ||
 532             hpte[1] != vcpu->arch.pgfault_hpte[1])
 533                 return RESUME_GUEST;
 534
 535         /* Translate the logical address and get the page */
 536         psize = hpte_page_size(hpte[0], r);
 537         gpa_base = r & HPTE_R_RPN & ~(psize - 1);
 538         gfn_base = gpa_base >> PAGE_SHIFT;
 539         gpa = gpa_base | (ea & (psize - 1));
 540         gfn = gpa >> PAGE_SHIFT;
 541         memslot = gfn_to_memslot(kvm, gfn);
 542
 543         trace_kvm_page_fault_enter(vcpu, hpte, memslot, ea, dsisr);
 544
 545         /* No memslot means it's an emulated MMIO region */
 546         if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
 547                 return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea,
 548                                               dsisr & DSISR_ISSTORE);
 549
 550         /*
 551          * This should never happen, because of the slot_is_aligned()
 552          * check in kvmppc_do_h_enter().
 553          */
 554         if (gfn_base < memslot->base_gfn)
 555                 return -EFAULT;
 556
 557         /* used to check for invalidations in progress */
 558         mmu_seq = kvm->mmu_notifier_seq;
 559         smp_rmb();
 560
 561         ret = -EFAULT;
 562         is_ci = false;
 563         pfn = 0;
 564         page = NULL;
 565         pte_size = PAGE_SIZE;
 566         writing = (dsisr & DSISR_ISSTORE) != 0;
 567         /* If writing != 0, then the HPTE must allow writing, if we get here */
 568         write_ok = writing;
 569         hva = gfn_to_hva_memslot(memslot, gfn);
 570         npages = get_user_pages_fast(hva, 1, writing, pages);
 571         if (npages < 1) {
 572                 /* Check if it's an I/O mapping */
 573                 down_read(&current->mm->mmap_sem);
 574                 vma = find_vma(current->mm, hva);
 575                 if (vma && vma->vm_start <= hva && hva + psize <= vma->vm_end &&
 576                     (vma->vm_flags & VM_PFNMAP)) {
 577                         pfn = vma->vm_pgoff +
 578                                 ((hva - vma->vm_start) >> PAGE_SHIFT);
 579                         pte_size = psize;
 580                         is_ci = pte_ci(__pte((pgprot_val(vma->vm_page_prot))));
 581                         write_ok = vma->vm_flags & VM_WRITE;
 582                 }
 583                 up_read(&current->mm->mmap_sem);
 584                 if (!pfn)
 585                         goto out_put;
 586         } else {
 587                 page = pages[0];
 588                 pfn = page_to_pfn(page);
 589                 if (PageHuge(page)) {
 590                         page = compound_head(page);
 591                         pte_size <<= compound_order(page);
 592                 }
 593                 /* if the guest wants write access, see if that is OK */
 594                 if (!writing && hpte_is_writable(r)) {
 595                         pte_t *ptep, pte;
 596                         unsigned long flags;
 597                         /*
 598                          * We need to protect against page table destruction
 599                          * hugepage split and collapse.
 600                          */
 601                         local_irq_save(flags);
 602                         ptep = find_linux_pte_or_hugepte(current->mm->pgd,
 603                                                          hva, NULL, NULL);
 604                         if (ptep) {
 605                                 pte = kvmppc_read_update_linux_pte(ptep, 1);
 606                                 if (__pte_write(pte))
 607                                         write_ok = 1;
 608                         }
 609                         local_irq_restore(flags);
 610                 }
 611         }
 612
 613         if (psize > pte_size)
 614                 goto out_put;
 615
 616         /* Check WIMG vs. the actual page we're accessing */
 617         if (!hpte_cache_flags_ok(r, is_ci)) {
 618                 if (is_ci)
 619                         goto out_put;
 620                 /*
 621                  * Allow guest to map emulated device memory as
 622                  * uncacheable, but actually make it cacheable.
 623                  */
 624                 r = (r & ~(HPTE_R_W|HPTE_R_I|HPTE_R_G)) | HPTE_R_M;
 625         }
 626
 627         /*
 628          * Set the HPTE to point to pfn.
 629          * Since the pfn is at PAGE_SIZE granularity, make sure we
 630          * don't mask out lower-order bits if psize < PAGE_SIZE.
 631          */
 632         if (psize < PAGE_SIZE)
 633                 psize = PAGE_SIZE;
 634         r = (r & HPTE_R_KEY_HI) | (r & ~(HPTE_R_PP0 - psize)) |
 635                                         ((pfn << PAGE_SHIFT) & ~(psize - 1));
 636         if (hpte_is_writable(r) && !write_ok)
 637                 r = hpte_make_readonly(r);
 638         ret = RESUME_GUEST;
 639         preempt_disable();
 640         while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
 641                 cpu_relax();
 642         hnow_v = be64_to_cpu(hptep[0]);
 643         hnow_r = be64_to_cpu(hptep[1]);
 644         if (cpu_has_feature(CPU_FTR_ARCH_300)) {
 645                 hnow_v = hpte_new_to_old_v(hnow_v, hnow_r);
 646                 hnow_r = hpte_new_to_old_r(hnow_r);
 647         }
 648         if ((hnow_v & ~HPTE_V_HVLOCK) != hpte[0] || hnow_r != hpte[1] ||
 649             rev->guest_rpte != hpte[2])
 650                 /* HPTE has been changed under us; let the guest retry */
 651                 goto out_unlock;
 652         hpte[0] = (hpte[0] & ~HPTE_V_ABSENT) | HPTE_V_VALID;
 653
 654         /* Always put the HPTE in the rmap chain for the page base address */
 655         rmap = &memslot->arch.rmap[gfn_base - memslot->base_gfn];
 656         lock_rmap(rmap);
 657
 658         /* Check if we might have been invalidated; let the guest retry if so */
 659         ret = RESUME_GUEST;
 660         if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) {
 661                 unlock_rmap(rmap);
 662                 goto out_unlock;
 663         }
 664
 665         /* Only set R/C in real HPTE if set in both *rmap and guest_rpte */
 666         rcbits = *rmap >> KVMPPC_RMAP_RC_SHIFT;
 667         r &= rcbits | ~(HPTE_R_R | HPTE_R_C);
 668
 669         if (be64_to_cpu(hptep[0]) & HPTE_V_VALID) {
 670                 /* HPTE was previously valid, so we need to invalidate it */
 671                 unlock_rmap(rmap);
 672                 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
 673                 kvmppc_invalidate_hpte(kvm, hptep, index);
 674                 /* don't lose previous R and C bits */
 675                 r |= be64_to_cpu(hptep[1]) & (HPTE_R_R | HPTE_R_C);
 676         } else {
 677                 kvmppc_add_revmap_chain(kvm, rev, rmap, index, 0);
 678         }
 679
 680         if (cpu_has_feature(CPU_FTR_ARCH_300)) {
 681                 r = hpte_old_to_new_r(hpte[0], r);
 682                 hpte[0] = hpte_old_to_new_v(hpte[0]);
 683         }
 684         hptep[1] = cpu_to_be64(r);
 685         eieio();
 686         __unlock_hpte(hptep, hpte[0]);
 687         asm volatile("ptesync" : : : "memory");
 688         preempt_enable();
 689         if (page && hpte_is_writable(r))
 690                 SetPageDirty(page);
 691
 692  out_put:
 693         trace_kvm_page_fault_exit(vcpu, hpte, ret);
 694
 695         if (page) {
 696                 /*
 697                  * We drop pages[0] here, not page because page might
 698                  * have been set to the head page of a compound, but
 699                  * we have to drop the reference on the correct tail
 700                  * page to match the get inside gup()
 701                  */
 702                 put_page(pages[0]);
 703         }
 704         return ret;
 705
 706  out_unlock:
 707         __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
 708         preempt_enable();
 709         goto out_put;
 710 }
 711
 712 static void kvmppc_rmap_reset(struct kvm *kvm)
 713 {
 714         struct kvm_memslots *slots;
 715         struct kvm_memory_slot *memslot;
 716         int srcu_idx;
 717
 718         srcu_idx = srcu_read_lock(&kvm->srcu);
 719         slots = kvm_memslots(kvm);
 720         kvm_for_each_memslot(memslot, slots) {
 721                 /*
 722                  * This assumes it is acceptable to lose reference and
 723                  * change bits across a reset.
 724                  */
 725                 memset(memslot->arch.rmap, 0,
 726                        memslot->npages * sizeof(*memslot->arch.rmap));
 727         }
 728         srcu_read_unlock(&kvm->srcu, srcu_idx);
 729 }
 730
 731 typedef int (*hva_handler_fn)(struct kvm *kvm, struct kvm_memory_slot *memslot,
 732                               unsigned long gfn);
 733
 734 static int kvm_handle_hva_range(struct kvm *kvm,
 735                                 unsigned long start,
 736                                 unsigned long end,
 737                                 hva_handler_fn handler)
 738 {
 739         int ret;
 740         int retval = 0;
 741         struct kvm_memslots *slots;
 742         struct kvm_memory_slot *memslot;
 743
 744         slots = kvm_memslots(kvm);
 745         kvm_for_each_memslot(memslot, slots) {
 746                 unsigned long hva_start, hva_end;
 747                 gfn_t gfn, gfn_end;
 748
 749                 hva_start = max(start, memslot->userspace_addr);
 750                 hva_end = min(end, memslot->userspace_addr +
 751                                         (memslot->npages << PAGE_SHIFT));
 752                 if (hva_start >= hva_end)
 753                         continue;
 754                 /*
 755                  * {gfn(page) | page intersects with [hva_start, hva_end)} =
 756                  * {gfn, gfn+1, ..., gfn_end-1}.
 757                  */
 758                 gfn = hva_to_gfn_memslot(hva_start, memslot);
 759                 gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);
 760
 761                 for (; gfn < gfn_end; ++gfn) {
 762                         ret = handler(kvm, memslot, gfn);
 763                         retval |= ret;
 764                 }
 765         }
 766
 767         return retval;
 768 }
 769
 770 static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
 771                           hva_handler_fn handler)
 772 {
 773         return kvm_handle_hva_range(kvm, hva, hva + 1, handler);
 774 }
 775
 776 /* Must be called with both HPTE and rmap locked */
 777 static void kvmppc_unmap_hpte(struct kvm *kvm, unsigned long i,
 778                               unsigned long *rmapp, unsigned long gfn)
 779 {
 780         __be64 *hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
 781         struct revmap_entry *rev = kvm->arch.hpt.rev;
 782         unsigned long j, h;
 783         unsigned long ptel, psize, rcbits;
 784
 785         j = rev[i].forw;
 786         if (j == i) {
 787                 /* chain is now empty */
 788                 *rmapp &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX);
 789         } else {
 790                 /* remove i from chain */
 791                 h = rev[i].back;
 792                 rev[h].forw = j;
 793                 rev[j].back = h;
 794                 rev[i].forw = rev[i].back = i;
 795                 *rmapp = (*rmapp & ~KVMPPC_RMAP_INDEX) | j;
 796         }
 797
 798         /* Now check and modify the HPTE */
 799         ptel = rev[i].guest_rpte;
 800         psize = hpte_page_size(be64_to_cpu(hptep[0]), ptel);
 801         if ((be64_to_cpu(hptep[0]) & HPTE_V_VALID) &&
 802             hpte_rpn(ptel, psize) == gfn) {
 803                 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
 804                 kvmppc_invalidate_hpte(kvm, hptep, i);
 805                 hptep[1] &= ~cpu_to_be64(HPTE_R_KEY_HI | HPTE_R_KEY_LO);
 806                 /* Harvest R and C */
 807                 rcbits = be64_to_cpu(hptep[1]) & (HPTE_R_R | HPTE_R_C);
 808                 *rmapp |= rcbits << KVMPPC_RMAP_RC_SHIFT;
 809                 if (rcbits & HPTE_R_C)
 810                         kvmppc_update_rmap_change(rmapp, psize);
 811                 if (rcbits & ~rev[i].guest_rpte) {
 812                         rev[i].guest_rpte = ptel | rcbits;
 813                         note_hpte_modification(kvm, &rev[i]);
 814                 }
 815         }
 816 }
 817
 818 static int kvm_unmap_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot,
 819                            unsigned long gfn)
 820 {
 821         unsigned long i;
 822         __be64 *hptep;
 823         unsigned long *rmapp;
 824
 825         rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
 826         for (;;) {
 827                 lock_rmap(rmapp);
 828                 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
 829                         unlock_rmap(rmapp);
 830                         break;
 831                 }
 832
 833                 /*
 834                  * To avoid an ABBA deadlock with the HPTE lock bit,
 835                  * we can't spin on the HPTE lock while holding the
 836                  * rmap chain lock.
 837                  */
 838                 i = *rmapp & KVMPPC_RMAP_INDEX;
 839                 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
 840                 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
 841                         /* unlock rmap before spinning on the HPTE lock */
 842                         unlock_rmap(rmapp);
 843                         while (be64_to_cpu(hptep[0]) & HPTE_V_HVLOCK)
 844                                 cpu_relax();
 845                         continue;
 846                 }
 847
 848                 kvmppc_unmap_hpte(kvm, i, rmapp, gfn);
 849                 unlock_rmap(rmapp);
 850                 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
 851         }
 852         return 0;
 853 }
 854
 855 int kvm_unmap_hva_hv(struct kvm *kvm, unsigned long hva)
 856 {
 857         hva_handler_fn handler;
 858
 859         handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp;
 860         kvm_handle_hva(kvm, hva, handler);
 861         return 0;
 862 }
 863
 864 int kvm_unmap_hva_range_hv(struct kvm *kvm, unsigned long start, unsigned long end)
 865 {
 866         hva_handler_fn handler;
 867
 868         handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp;
 869         kvm_handle_hva_range(kvm, start, end, handler);
 870         return 0;
 871 }
 872
 873 void kvmppc_core_flush_memslot_hv(struct kvm *kvm,
 874                                   struct kvm_memory_slot *memslot)
 875 {
 876         unsigned long gfn;
 877         unsigned long n;
 878         unsigned long *rmapp;
 879
 880         gfn = memslot->base_gfn;
 881         rmapp = memslot->arch.rmap;
 882         for (n = memslot->npages; n; --n, ++gfn) {
 883                 if (kvm_is_radix(kvm)) {
 884                         kvm_unmap_radix(kvm, memslot, gfn);
 885                         continue;
 886                 }
 887                 /*
 888                  * Testing the present bit without locking is OK because
 889                  * the memslot has been marked invalid already, and hence
 890                  * no new HPTEs referencing this page can be created,
 891                  * thus the present bit can't go from 0 to 1.
 892                  */
 893                 if (*rmapp & KVMPPC_RMAP_PRESENT)
 894                         kvm_unmap_rmapp(kvm, memslot, gfn);
 895                 ++rmapp;
 896         }
 897 }
 898
 899 static int kvm_age_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot,
 900                          unsigned long gfn)
 901 {
 902         struct revmap_entry *rev = kvm->arch.hpt.rev;
 903         unsigned long head, i, j;
 904         __be64 *hptep;
 905         int ret = 0;
 906         unsigned long *rmapp;
 907
 908         rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
 909  retry:
 910         lock_rmap(rmapp);
 911         if (*rmapp & KVMPPC_RMAP_REFERENCED) {
 912                 *rmapp &= ~KVMPPC_RMAP_REFERENCED;
 913                 ret = 1;
 914         }
 915         if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
 916                 unlock_rmap(rmapp);
 917                 return ret;
 918         }
 919
 920         i = head = *rmapp & KVMPPC_RMAP_INDEX;
 921         do {
 922                 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
 923                 j = rev[i].forw;
 924
 925                 /* If this HPTE isn't referenced, ignore it */
 926                 if (!(be64_to_cpu(hptep[1]) & HPTE_R_R))
 927                         continue;
 928
 929                 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
 930                         /* unlock rmap before spinning on the HPTE lock */
 931                         unlock_rmap(rmapp);
 932                         while (be64_to_cpu(hptep[0]) & HPTE_V_HVLOCK)
 933                                 cpu_relax();
 934                         goto retry;
 935                 }
 936
 937                 /* Now check and modify the HPTE */
 938                 if ((be64_to_cpu(hptep[0]) & HPTE_V_VALID) &&
 939                     (be64_to_cpu(hptep[1]) & HPTE_R_R)) {
 940                         kvmppc_clear_ref_hpte(kvm, hptep, i);
 941                         if (!(rev[i].guest_rpte & HPTE_R_R)) {
 942                                 rev[i].guest_rpte |= HPTE_R_R;
 943                                 note_hpte_modification(kvm, &rev[i]);
 944                         }
 945                         ret = 1;
 946                 }
 947                 __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
 948         } while ((i = j) != head);
 949
 950         unlock_rmap(rmapp);
 951         return ret;
 952 }
 953
 954 int kvm_age_hva_hv(struct kvm *kvm, unsigned long start, unsigned long end)
 955 {
 956         hva_handler_fn handler;
 957
 958         handler = kvm_is_radix(kvm) ? kvm_age_radix : kvm_age_rmapp;
 959         return kvm_handle_hva_range(kvm, start, end, handler);
 960 }
 961
 962 static int kvm_test_age_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot,
 963                               unsigned long gfn)
 964 {
 965         struct revmap_entry *rev = kvm->arch.hpt.rev;
 966         unsigned long head, i, j;
 967         unsigned long *hp;
 968         int ret = 1;
 969         unsigned long *rmapp;
 970
 971         rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
 972         if (*rmapp & KVMPPC_RMAP_REFERENCED)
 973                 return 1;
 974
 975         lock_rmap(rmapp);
 976         if (*rmapp & KVMPPC_RMAP_REFERENCED)
 977                 goto out;
 978
 979         if (*rmapp & KVMPPC_RMAP_PRESENT) {
 980                 i = head = *rmapp & KVMPPC_RMAP_INDEX;
 981                 do {
 982                         hp = (unsigned long *)(kvm->arch.hpt.virt + (i << 4));
 983                         j = rev[i].forw;
 984                         if (be64_to_cpu(hp[1]) & HPTE_R_R)
 985                                 goto out;
 986                 } while ((i = j) != head);
 987         }
 988         ret = 0;
 989
 990  out:
 991         unlock_rmap(rmapp);
 992         return ret;
 993 }
 994
 995 int kvm_test_age_hva_hv(struct kvm *kvm, unsigned long hva)
 996 {
 997         hva_handler_fn handler;
 998
 999         handler = kvm_is_radix(kvm) ? kvm_test_age_radix : kvm_test_age_rmapp;
1000         return kvm_handle_hva(kvm, hva, handler);
1001 }
1002
1003 void kvm_set_spte_hva_hv(struct kvm *kvm, unsigned long hva, pte_t pte)
1004 {
1005         hva_handler_fn handler;
1006
1007         handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp;
1008         kvm_handle_hva(kvm, hva, handler);
1009 }
1010
1011 static int vcpus_running(struct kvm *kvm)
1012 {
1013         return atomic_read(&kvm->arch.vcpus_running) != 0;
1014 }
1015
1016 /*
1017  * Returns the number of system pages that are dirty.
1018  * This can be more than 1 if we find a huge-page HPTE.
1019  */
1020 static int kvm_test_clear_dirty_npages(struct kvm *kvm, unsigned long *rmapp)
1021 {
1022         struct revmap_entry *rev = kvm->arch.hpt.rev;
1023         unsigned long head, i, j;
1024         unsigned long n;
1025         unsigned long v, r;
1026         __be64 *hptep;
1027         int npages_dirty = 0;
1028
1029  retry:
1030         lock_rmap(rmapp);
1031         if (*rmapp & KVMPPC_RMAP_CHANGED) {
1032                 long change_order = (*rmapp & KVMPPC_RMAP_CHG_ORDER)
1033                         >> KVMPPC_RMAP_CHG_SHIFT;
1034                 *rmapp &= ~(KVMPPC_RMAP_CHANGED | KVMPPC_RMAP_CHG_ORDER);
1035                 npages_dirty = 1;
1036                 if (change_order > PAGE_SHIFT)
1037                         npages_dirty = 1ul << (change_order - PAGE_SHIFT);
1038         }
1039         if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
1040                 unlock_rmap(rmapp);
1041                 return npages_dirty;
1042         }
1043
1044         i = head = *rmapp & KVMPPC_RMAP_INDEX;
1045         do {
1046                 unsigned long hptep1;
1047                 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4));
1048                 j = rev[i].forw;
1049
1050                 /*
1051                  * Checking the C (changed) bit here is racy since there
1052                  * is no guarantee about when the hardware writes it back.
1053                  * If the HPTE is not writable then it is stable since the
1054                  * page can't be written to, and we would have done a tlbie
1055                  * (which forces the hardware to complete any writeback)
1056                  * when making the HPTE read-only.
1057                  * If vcpus are running then this call is racy anyway
1058                  * since the page could get dirtied subsequently, so we
1059                  * expect there to be a further call which would pick up
1060                  * any delayed C bit writeback.
1061                  * Otherwise we need to do the tlbie even if C==0 in
1062                  * order to pick up any delayed writeback of C.
1063                  */
1064                 hptep1 = be64_to_cpu(hptep[1]);
1065                 if (!(hptep1 & HPTE_R_C) &&
1066                     (!hpte_is_writable(hptep1) || vcpus_running(kvm)))
1067                         continue;
1068
1069                 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
1070                         /* unlock rmap before spinning on the HPTE lock */
1071                         unlock_rmap(rmapp);
1072                         while (hptep[0] & cpu_to_be64(HPTE_V_HVLOCK))
1073                                 cpu_relax();
1074                         goto retry;
1075                 }
1076
1077                 /* Now check and modify the HPTE */
1078                 if (!(hptep[0] & cpu_to_be64(HPTE_V_VALID))) {
1079                         __unlock_hpte(hptep, be64_to_cpu(hptep[0]));
1080                         continue;
1081                 }
1082
1083                 /* need to make it temporarily absent so C is stable */
1084                 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
1085                 kvmppc_invalidate_hpte(kvm, hptep, i);
1086                 v = be64_to_cpu(hptep[0]);
1087                 r = be64_to_cpu(hptep[1]);
1088                 if (r & HPTE_R_C) {
1089                         hptep[1] = cpu_to_be64(r & ~HPTE_R_C);
1090                         if (!(rev[i].guest_rpte & HPTE_R_C)) {
1091                                 rev[i].guest_rpte |= HPTE_R_C;
1092                                 note_hpte_modification(kvm, &rev[i]);
1093                         }
1094                         n = hpte_page_size(v, r);
1095                         n = (n + PAGE_SIZE - 1) >> PAGE_SHIFT;
1096                         if (n > npages_dirty)
1097                                 npages_dirty = n;
1098                         eieio();
1099                 }
1100                 v &= ~HPTE_V_ABSENT;
1101                 v |= HPTE_V_VALID;
1102                 __unlock_hpte(hptep, v);
1103         } while ((i = j) != head);
1104
1105         unlock_rmap(rmapp);
1106         return npages_dirty;
1107 }
1108
1109 void kvmppc_harvest_vpa_dirty(struct kvmppc_vpa *vpa,
1110                               struct kvm_memory_slot *memslot,
1111                               unsigned long *map)
1112 {
1113         unsigned long gfn;
1114
1115         if (!vpa->dirty || !vpa->pinned_addr)
1116                 return;
1117         gfn = vpa->gpa >> PAGE_SHIFT;
1118         if (gfn < memslot->base_gfn ||
1119             gfn >= memslot->base_gfn + memslot->npages)
1120                 return;
1121
1122         vpa->dirty = false;
1123         if (map)
1124                 __set_bit_le(gfn - memslot->base_gfn, map);
1125 }
1126
1127 long kvmppc_hv_get_dirty_log_hpt(struct kvm *kvm,
1128                         struct kvm_memory_slot *memslot, unsigned long *map)
1129 {
1130         unsigned long i, j;
1131         unsigned long *rmapp;
1132
1133         preempt_disable();
1134         rmapp = memslot->arch.rmap;
1135         for (i = 0; i < memslot->npages; ++i) {
1136                 int npages = kvm_test_clear_dirty_npages(kvm, rmapp);
1137                 /*
1138                  * Note that if npages > 0 then i must be a multiple of npages,
1139                  * since we always put huge-page HPTEs in the rmap chain
1140                  * corresponding to their page base address.
1141                  */
1142                 if (npages && map)
1143                         for (j = i; npages; ++j, --npages)
1144                                 __set_bit_le(j, map);
1145                 ++rmapp;
1146         }
1147         preempt_enable();
1148         return 0;
1149 }
1150
1151 void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
1152                             unsigned long *nb_ret)
1153 {
1154         struct kvm_memory_slot *memslot;
1155         unsigned long gfn = gpa >> PAGE_SHIFT;
1156         struct page *page, *pages[1];
1157         int npages;
1158         unsigned long hva, offset;
1159         int srcu_idx;
1160
1161         srcu_idx = srcu_read_lock(&kvm->srcu);
1162         memslot = gfn_to_memslot(kvm, gfn);
1163         if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
1164                 goto err;
1165         hva = gfn_to_hva_memslot(memslot, gfn);
1166         npages = get_user_pages_fast(hva, 1, 1, pages);
1167         if (npages < 1)
1168                 goto err;
1169         page = pages[0];
1170         srcu_read_unlock(&kvm->srcu, srcu_idx);
1171
1172         offset = gpa & (PAGE_SIZE - 1);
1173         if (nb_ret)
1174                 *nb_ret = PAGE_SIZE - offset;
1175         return page_address(page) + offset;
1176
1177  err:
1178         srcu_read_unlock(&kvm->srcu, srcu_idx);
1179         return NULL;
1180 }
1181
1182 void kvmppc_unpin_guest_page(struct kvm *kvm, void *va, unsigned long gpa,
1183                              bool dirty)
1184 {
1185         struct page *page = virt_to_page(va);
1186         struct kvm_memory_slot *memslot;
1187         unsigned long gfn;
1188         unsigned long *rmap;
1189         int srcu_idx;
1190
1191         put_page(page);
1192
1193         if (!dirty)
1194                 return;
1195
1196         /* We need to mark this page dirty in the rmap chain */
1197         gfn = gpa >> PAGE_SHIFT;
1198         srcu_idx = srcu_read_lock(&kvm->srcu);
1199         memslot = gfn_to_memslot(kvm, gfn);
1200         if (memslot) {
1201                 if (!kvm_is_radix(kvm)) {
1202                         rmap = &memslot->arch.rmap[gfn - memslot->base_gfn];
1203                         lock_rmap(rmap);
1204                         *rmap |= KVMPPC_RMAP_CHANGED;
1205                         unlock_rmap(rmap);
1206                 } else if (memslot->dirty_bitmap) {
1207                         mark_page_dirty(kvm, gfn);
1208                 }
1209         }
1210         srcu_read_unlock(&kvm->srcu, srcu_idx);
1211 }
1212
1213 /*
1214  * HPT resizing
1215  */
1216 static int resize_hpt_allocate(struct kvm_resize_hpt *resize)
1217 {
1218         int rc;
1219
1220         rc = kvmppc_allocate_hpt(&resize->hpt, resize->order);
1221         if (rc < 0)
1222                 return rc;
1223
1224         resize_hpt_debug(resize, "resize_hpt_allocate(): HPT @ 0x%lx\n",
1225                          resize->hpt.virt);
1226
1227         return 0;
1228 }
1229
1230 static unsigned long resize_hpt_rehash_hpte(struct kvm_resize_hpt *resize,
1231                                             unsigned long idx)
1232 {
1233         struct kvm *kvm = resize->kvm;
1234         struct kvm_hpt_info *old = &kvm->arch.hpt;
1235         struct kvm_hpt_info *new = &resize->hpt;
1236         unsigned long old_hash_mask = (1ULL << (old->order - 7)) - 1;
1237         unsigned long new_hash_mask = (1ULL << (new->order - 7)) - 1;
1238         __be64 *hptep, *new_hptep;
1239         unsigned long vpte, rpte, guest_rpte;
1240         int ret;
1241         struct revmap_entry *rev;
1242         unsigned long apsize, psize, avpn, pteg, hash;
1243         unsigned long new_idx, new_pteg, replace_vpte;
1244
1245         hptep = (__be64 *)(old->virt + (idx << 4));
1246
1247         /* Guest is stopped, so new HPTEs can't be added or faulted
1248          * in, only unmapped or altered by host actions.  So, it's
1249          * safe to check this before we take the HPTE lock */
1250         vpte = be64_to_cpu(hptep[0]);
1251         if (!(vpte & HPTE_V_VALID) && !(vpte & HPTE_V_ABSENT))
1252                 return 0; /* nothing to do */
1253
1254         while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
1255                 cpu_relax();
1256
1257         vpte = be64_to_cpu(hptep[0]);
1258
1259         ret = 0;
1260         if (!(vpte & HPTE_V_VALID) && !(vpte & HPTE_V_ABSENT))
1261                 /* Nothing to do */
1262                 goto out;
1263
1264         /* Unmap */
1265         rev = &old->rev[idx];
1266         guest_rpte = rev->guest_rpte;
1267
1268         ret = -EIO;
1269         apsize = hpte_page_size(vpte, guest_rpte);
1270         if (!apsize)
1271                 goto out;
1272
1273         if (vpte & HPTE_V_VALID) {
1274                 unsigned long gfn = hpte_rpn(guest_rpte, apsize);
1275                 int srcu_idx = srcu_read_lock(&kvm->srcu);
1276                 struct kvm_memory_slot *memslot =
1277                         __gfn_to_memslot(kvm_memslots(kvm), gfn);
1278
1279                 if (memslot) {
1280                         unsigned long *rmapp;
1281                         rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
1282
1283                         lock_rmap(rmapp);
1284                         kvmppc_unmap_hpte(kvm, idx, rmapp, gfn);
1285                         unlock_rmap(rmapp);
1286                 }
1287
1288                 srcu_read_unlock(&kvm->srcu, srcu_idx);
1289         }
1290
1291         /* Reload PTE after unmap */
1292         vpte = be64_to_cpu(hptep[0]);
1293
1294         BUG_ON(vpte & HPTE_V_VALID);
1295         BUG_ON(!(vpte & HPTE_V_ABSENT));
1296
1297         ret = 0;
1298         if (!(vpte & HPTE_V_BOLTED))
1299                 goto out;
1300
1301         rpte = be64_to_cpu(hptep[1]);
1302         psize = hpte_base_page_size(vpte, rpte);
1303         avpn = HPTE_V_AVPN_VAL(vpte) & ~((psize - 1) >> 23);
1304         pteg = idx / HPTES_PER_GROUP;
1305         if (vpte & HPTE_V_SECONDARY)
1306                 pteg = ~pteg;
1307
1308         if (!(vpte & HPTE_V_1TB_SEG)) {
1309                 unsigned long offset, vsid;
1310
1311                 /* We only have 28 - 23 bits of offset in avpn */
1312                 offset = (avpn & 0x1f) << 23;
1313                 vsid = avpn >> 5;
1314                 /* We can find more bits from the pteg value */
1315                 if (psize < (1ULL << 23))
1316                         offset |= ((vsid ^ pteg) & old_hash_mask) * psize;
1317
1318                 hash = vsid ^ (offset / psize);
1319         } else {
1320                 unsigned long offset, vsid;
1321
1322                 /* We only have 40 - 23 bits of seg_off in avpn */
1323                 offset = (avpn & 0x1ffff) << 23;
1324                 vsid = avpn >> 17;
1325                 if (psize < (1ULL << 23))
1326                         offset |= ((vsid ^ (vsid << 25) ^ pteg) & old_hash_mask) * psize;
1327
1328                 hash = vsid ^ (vsid << 25) ^ (offset / psize);
1329         }
1330
1331         new_pteg = hash & new_hash_mask;
1332         if (vpte & HPTE_V_SECONDARY) {
1333                 BUG_ON(~pteg != (hash & old_hash_mask));
1334                 new_pteg = ~new_pteg;
1335         } else {
1336                 BUG_ON(pteg != (hash & old_hash_mask));
1337         }
1338
1339         new_idx = new_pteg * HPTES_PER_GROUP + (idx % HPTES_PER_GROUP);
1340         new_hptep = (__be64 *)(new->virt + (new_idx << 4));
1341
1342         replace_vpte = be64_to_cpu(new_hptep[0]);
1343
1344         if (replace_vpte & (HPTE_V_VALID | HPTE_V_ABSENT)) {
1345                 BUG_ON(new->order >= old->order);
1346
1347                 if (replace_vpte & HPTE_V_BOLTED) {
1348                         if (vpte & HPTE_V_BOLTED)
1349                                 /* Bolted collision, nothing we can do */
1350                                 ret = -ENOSPC;
1351                         /* Discard the new HPTE */
1352                         goto out;
1353                 }
1354
1355                 /* Discard the previous HPTE */
1356         }
1357
1358         new_hptep[1] = cpu_to_be64(rpte);
1359         new->rev[new_idx].guest_rpte = guest_rpte;
1360         /* No need for a barrier, since new HPT isn't active */
1361         new_hptep[0] = cpu_to_be64(vpte);
1362         unlock_hpte(new_hptep, vpte);
1363
1364 out:
1365         unlock_hpte(hptep, vpte);
1366         return ret;
1367 }
1368
1369 static int resize_hpt_rehash(struct kvm_resize_hpt *resize)
1370 {
1371         struct kvm *kvm = resize->kvm;
1372         unsigned  long i;
1373         int rc;
1374
1375         /*
1376          * resize_hpt_rehash_hpte() doesn't handle the new-format HPTEs
1377          * that POWER9 uses, and could well hit a BUG_ON on POWER9.
1378          */
1379         if (cpu_has_feature(CPU_FTR_ARCH_300))
1380                 return -EIO;
1381         for (i = 0; i < kvmppc_hpt_npte(&kvm->arch.hpt); i++) {
1382                 rc = resize_hpt_rehash_hpte(resize, i);
1383                 if (rc != 0)
1384                         return rc;
1385         }
1386
1387         return 0;
1388 }
1389
1390 static void resize_hpt_pivot(struct kvm_resize_hpt *resize)
1391 {
1392         struct kvm *kvm = resize->kvm;
1393         struct kvm_hpt_info hpt_tmp;
1394
1395         /* Exchange the pending tables in the resize structure with
1396          * the active tables */
1397
1398         resize_hpt_debug(resize, "resize_hpt_pivot()\n");
1399
1400         spin_lock(&kvm->mmu_lock);
1401         asm volatile("ptesync" : : : "memory");
1402
1403         hpt_tmp = kvm->arch.hpt;
1404         kvmppc_set_hpt(kvm, &resize->hpt);
1405         resize->hpt = hpt_tmp;
1406
1407         spin_unlock(&kvm->mmu_lock);
1408
1409         synchronize_srcu_expedited(&kvm->srcu);
1410
1411         resize_hpt_debug(resize, "resize_hpt_pivot() done\n");
1412 }
1413
1414 static void resize_hpt_release(struct kvm *kvm, struct kvm_resize_hpt *resize)
1415 {
1416         BUG_ON(kvm->arch.resize_hpt != resize);
1417
1418         if (!resize)
1419                 return;
1420
1421         if (resize->hpt.virt)
1422                 kvmppc_free_hpt(&resize->hpt);
1423
1424         kvm->arch.resize_hpt = NULL;
1425         kfree(resize);
1426 }
1427
1428 static void resize_hpt_prepare_work(struct work_struct *work)
1429 {
1430         struct kvm_resize_hpt *resize = container_of(work,
1431                                                      struct kvm_resize_hpt,
1432                                                      work);
1433         struct kvm *kvm = resize->kvm;
1434         int err;
1435
1436         resize_hpt_debug(resize, "resize_hpt_prepare_work(): order = %d\n",
1437                          resize->order);
1438
1439         err = resize_hpt_allocate(resize);
1440
1441         mutex_lock(&kvm->lock);
1442
1443         resize->error = err;
1444         resize->prepare_done = true;
1445
1446         mutex_unlock(&kvm->lock);
1447 }
1448
1449 long kvm_vm_ioctl_resize_hpt_prepare(struct kvm *kvm,
1450                                      struct kvm_ppc_resize_hpt *rhpt)
1451 {
1452         unsigned long flags = rhpt->flags;
1453         unsigned long shift = rhpt->shift;
1454         struct kvm_resize_hpt *resize;
1455         int ret;
1456
1457         if (flags != 0)
1458                 return -EINVAL;
1459
1460         if (shift && ((shift < 18) || (shift > 46)))
1461                 return -EINVAL;
1462
1463         mutex_lock(&kvm->lock);
1464
1465         resize = kvm->arch.resize_hpt;
1466
1467         if (resize) {
1468                 if (resize->order == shift) {
1469                         /* Suitable resize in progress */
1470                         if (resize->prepare_done) {
1471                                 ret = resize->error;
1472                                 if (ret != 0)
1473                                         resize_hpt_release(kvm, resize);
1474                         } else {
1475                                 ret = 100; /* estimated time in ms */
1476                         }
1477
1478                         goto out;
1479                 }
1480
1481                 /* not suitable, cancel it */
1482                 resize_hpt_release(kvm, resize);
1483         }
1484
1485         ret = 0;
1486         if (!shift)
1487                 goto out; /* nothing to do */
1488
1489         /* start new resize */
1490
1491         resize = kzalloc(sizeof(*resize), GFP_KERNEL);
1492         if (!resize) {
1493                 ret = -ENOMEM;
1494                 goto out;
1495         }
1496         resize->order = shift;
1497         resize->kvm = kvm;
1498         INIT_WORK(&resize->work, resize_hpt_prepare_work);
1499         kvm->arch.resize_hpt = resize;
1500
1501         schedule_work(&resize->work);
1502
1503         ret = 100; /* estimated time in ms */
1504
1505 out:
1506         mutex_unlock(&kvm->lock);
1507         return ret;
1508 }
1509
1510 static void resize_hpt_boot_vcpu(void *opaque)
1511 {
1512         /* Nothing to do, just force a KVM exit */
1513 }
1514
1515 long kvm_vm_ioctl_resize_hpt_commit(struct kvm *kvm,
1516                                     struct kvm_ppc_resize_hpt *rhpt)
1517 {
1518         unsigned long flags = rhpt->flags;
1519         unsigned long shift = rhpt->shift;
1520         struct kvm_resize_hpt *resize;
1521         long ret;
1522
1523         if (flags != 0)
1524                 return -EINVAL;
1525
1526         if (shift && ((shift < 18) || (shift > 46)))
1527                 return -EINVAL;
1528
1529         mutex_lock(&kvm->lock);
1530
1531         resize = kvm->arch.resize_hpt;
1532
1533         /* This shouldn't be possible */
1534         ret = -EIO;
1535         if (WARN_ON(!kvm->arch.hpte_setup_done))
1536                 goto out_no_hpt;
1537
1538         /* Stop VCPUs from running while we mess with the HPT */
1539         kvm->arch.hpte_setup_done = 0;
1540         smp_mb();
1541
1542         /* Boot all CPUs out of the guest so they re-read
1543          * hpte_setup_done */
1544         on_each_cpu(resize_hpt_boot_vcpu, NULL, 1);
1545
1546         ret = -ENXIO;
1547         if (!resize || (resize->order != shift))
1548                 goto out;
1549
1550         ret = -EBUSY;
1551         if (!resize->prepare_done)
1552                 goto out;
1553
1554         ret = resize->error;
1555         if (ret != 0)
1556                 goto out;
1557
1558         ret = resize_hpt_rehash(resize);
1559         if (ret != 0)
1560                 goto out;
1561
1562         resize_hpt_pivot(resize);
1563
1564 out:
1565         /* Let VCPUs run again */
1566         kvm->arch.hpte_setup_done = 1;
1567         smp_mb();
1568 out_no_hpt:
1569         resize_hpt_release(kvm, resize);
1570         mutex_unlock(&kvm->lock);
1571         return ret;
1572 }
1573
1574 /*
1575  * Functions for reading and writing the hash table via reads and
1576  * writes on a file descriptor.
1577  *
1578  * Reads return the guest view of the hash table, which has to be
1579  * pieced together from the real hash table and the guest_rpte
1580  * values in the revmap array.
1581  *
1582  * On writes, each HPTE written is considered in turn, and if it
1583  * is valid, it is written to the HPT as if an H_ENTER with the
1584  * exact flag set was done.  When the invalid count is non-zero
1585  * in the header written to the stream, the kernel will make
1586  * sure that that many HPTEs are invalid, and invalidate them
1587  * if not.
1588  */
1589
1590 struct kvm_htab_ctx {
1591         unsigned long   index;
1592         unsigned long   flags;
1593         struct kvm      *kvm;
1594         int             first_pass;
1595 };
1596
1597 #define HPTE_SIZE       (2 * sizeof(unsigned long))
1598
1599 /*
1600  * Returns 1 if this HPT entry has been modified or has pending
1601  * R/C bit changes.
1602  */
1603 static int hpte_dirty(struct revmap_entry *revp, __be64 *hptp)
1604 {
1605         unsigned long rcbits_unset;
1606
1607         if (revp->guest_rpte & HPTE_GR_MODIFIED)
1608                 return 1;
1609
1610         /* Also need to consider changes in reference and changed bits */
1611         rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C);
1612         if ((be64_to_cpu(hptp[0]) & HPTE_V_VALID) &&
1613             (be64_to_cpu(hptp[1]) & rcbits_unset))
1614                 return 1;
1615
1616         return 0;
1617 }
1618
1619 static long record_hpte(unsigned long flags, __be64 *hptp,
1620                         unsigned long *hpte, struct revmap_entry *revp,
1621                         int want_valid, int first_pass)
1622 {
1623         unsigned long v, r, hr;
1624         unsigned long rcbits_unset;
1625         int ok = 1;
1626         int valid, dirty;
1627
1628         /* Unmodified entries are uninteresting except on the first pass */
1629         dirty = hpte_dirty(revp, hptp);
1630         if (!first_pass && !dirty)
1631                 return 0;
1632
1633         valid = 0;
1634         if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)) {
1635                 valid = 1;
1636                 if ((flags & KVM_GET_HTAB_BOLTED_ONLY) &&
1637                     !(be64_to_cpu(hptp[0]) & HPTE_V_BOLTED))
1638                         valid = 0;
1639         }
1640         if (valid != want_valid)
1641                 return 0;
1642
1643         v = r = 0;
1644         if (valid || dirty) {
1645                 /* lock the HPTE so it's stable and read it */
1646                 preempt_disable();
1647                 while (!try_lock_hpte(hptp, HPTE_V_HVLOCK))
1648                         cpu_relax();
1649                 v = be64_to_cpu(hptp[0]);
1650                 hr = be64_to_cpu(hptp[1]);
1651                 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
1652                         v = hpte_new_to_old_v(v, hr);
1653                         hr = hpte_new_to_old_r(hr);
1654                 }
1655
1656                 /* re-evaluate valid and dirty from synchronized HPTE value */
1657                 valid = !!(v & HPTE_V_VALID);
1658                 dirty = !!(revp->guest_rpte & HPTE_GR_MODIFIED);
1659
1660                 /* Harvest R and C into guest view if necessary */
1661                 rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C);
1662                 if (valid && (rcbits_unset & hr)) {
1663                         revp->guest_rpte |= (hr &
1664                                 (HPTE_R_R | HPTE_R_C)) | HPTE_GR_MODIFIED;
1665                         dirty = 1;
1666                 }
1667
1668                 if (v & HPTE_V_ABSENT) {
1669                         v &= ~HPTE_V_ABSENT;
1670                         v |= HPTE_V_VALID;
1671                         valid = 1;
1672                 }
1673                 if ((flags & KVM_GET_HTAB_BOLTED_ONLY) && !(v & HPTE_V_BOLTED))
1674                         valid = 0;
1675
1676                 r = revp->guest_rpte;
1677                 /* only clear modified if this is the right sort of entry */
1678                 if (valid == want_valid && dirty) {
1679                         r &= ~HPTE_GR_MODIFIED;
1680                         revp->guest_rpte = r;
1681                 }
1682                 unlock_hpte(hptp, be64_to_cpu(hptp[0]));
1683                 preempt_enable();
1684                 if (!(valid == want_valid && (first_pass || dirty)))
1685                         ok = 0;
1686         }
1687         hpte[0] = cpu_to_be64(v);
1688         hpte[1] = cpu_to_be64(r);
1689         return ok;
1690 }
1691
1692 static ssize_t kvm_htab_read(struct file *file, char __user *buf,
1693                              size_t count, loff_t *ppos)
1694 {
1695         struct kvm_htab_ctx *ctx = file->private_data;
1696         struct kvm *kvm = ctx->kvm;
1697         struct kvm_get_htab_header hdr;
1698         __be64 *hptp;
1699         struct revmap_entry *revp;
1700         unsigned long i, nb, nw;
1701         unsigned long __user *lbuf;
1702         struct kvm_get_htab_header __user *hptr;
1703         unsigned long flags;
1704         int first_pass;
1705         unsigned long hpte[2];
1706
1707         if (!access_ok(VERIFY_WRITE, buf, count))
1708                 return -EFAULT;
1709
1710         first_pass = ctx->first_pass;
1711         flags = ctx->flags;
1712
1713         i = ctx->index;
1714         hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
1715         revp = kvm->arch.hpt.rev + i;
1716         lbuf = (unsigned long __user *)buf;
1717
1718         nb = 0;
1719         while (nb + sizeof(hdr) + HPTE_SIZE < count) {
1720                 /* Initialize header */
1721                 hptr = (struct kvm_get_htab_header __user *)buf;
1722                 hdr.n_valid = 0;
1723                 hdr.n_invalid = 0;
1724                 nw = nb;
1725                 nb += sizeof(hdr);
1726                 lbuf = (unsigned long __user *)(buf + sizeof(hdr));
1727
1728                 /* Skip uninteresting entries, i.e. clean on not-first pass */
1729                 if (!first_pass) {
1730                         while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
1731                                !hpte_dirty(revp, hptp)) {
1732                                 ++i;
1733                                 hptp += 2;
1734                                 ++revp;
1735                         }
1736                 }
1737                 hdr.index = i;
1738
1739                 /* Grab a series of valid entries */
1740                 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
1741                        hdr.n_valid < 0xffff &&
1742                        nb + HPTE_SIZE < count &&
1743                        record_hpte(flags, hptp, hpte, revp, 1, first_pass)) {
1744                         /* valid entry, write it out */
1745                         ++hdr.n_valid;
1746                         if (__put_user(hpte[0], lbuf) ||
1747                             __put_user(hpte[1], lbuf + 1))
1748                                 return -EFAULT;
1749                         nb += HPTE_SIZE;
1750                         lbuf += 2;
1751                         ++i;
1752                         hptp += 2;
1753                         ++revp;
1754                 }
1755                 /* Now skip invalid entries while we can */
1756                 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
1757                        hdr.n_invalid < 0xffff &&
1758                        record_hpte(flags, hptp, hpte, revp, 0, first_pass)) {
1759                         /* found an invalid entry */
1760                         ++hdr.n_invalid;
1761                         ++i;
1762                         hptp += 2;
1763                         ++revp;
1764                 }
1765
1766                 if (hdr.n_valid || hdr.n_invalid) {
1767                         /* write back the header */
1768                         if (__copy_to_user(hptr, &hdr, sizeof(hdr)))
1769                                 return -EFAULT;
1770                         nw = nb;
1771                         buf = (char __user *)lbuf;
1772                 } else {
1773                         nb = nw;
1774                 }
1775
1776                 /* Check if we've wrapped around the hash table */
1777                 if (i >= kvmppc_hpt_npte(&kvm->arch.hpt)) {
1778                         i = 0;
1779                         ctx->first_pass = 0;
1780                         break;
1781                 }
1782         }
1783
1784         ctx->index = i;
1785
1786         return nb;
1787 }
1788
1789 static ssize_t kvm_htab_write(struct file *file, const char __user *buf,
1790                               size_t count, loff_t *ppos)
1791 {
1792         struct kvm_htab_ctx *ctx = file->private_data;
1793         struct kvm *kvm = ctx->kvm;
1794         struct kvm_get_htab_header hdr;
1795         unsigned long i, j;
1796         unsigned long v, r;
1797         unsigned long __user *lbuf;
1798         __be64 *hptp;
1799         unsigned long tmp[2];
1800         ssize_t nb;
1801         long int err, ret;
1802         int hpte_setup;
1803
1804         if (!access_ok(VERIFY_READ, buf, count))
1805                 return -EFAULT;
1806
1807         /* lock out vcpus from running while we're doing this */
1808         mutex_lock(&kvm->lock);
1809         hpte_setup = kvm->arch.hpte_setup_done;
1810         if (hpte_setup) {
1811                 kvm->arch.hpte_setup_done = 0;  /* temporarily */
1812                 /* order hpte_setup_done vs. vcpus_running */
1813                 smp_mb();
1814                 if (atomic_read(&kvm->arch.vcpus_running)) {
1815                         kvm->arch.hpte_setup_done = 1;
1816                         mutex_unlock(&kvm->lock);
1817                         return -EBUSY;
1818                 }
1819         }
1820
1821         err = 0;
1822         for (nb = 0; nb + sizeof(hdr) <= count; ) {
1823                 err = -EFAULT;
1824                 if (__copy_from_user(&hdr, buf, sizeof(hdr)))
1825                         break;
1826
1827                 err = 0;
1828                 if (nb + hdr.n_valid * HPTE_SIZE > count)
1829                         break;
1830
1831                 nb += sizeof(hdr);
1832                 buf += sizeof(hdr);
1833
1834                 err = -EINVAL;
1835                 i = hdr.index;
1836                 if (i >= kvmppc_hpt_npte(&kvm->arch.hpt) ||
1837                     i + hdr.n_valid + hdr.n_invalid > kvmppc_hpt_npte(&kvm->arch.hpt))
1838                         break;
1839
1840                 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
1841                 lbuf = (unsigned long __user *)buf;
1842                 for (j = 0; j < hdr.n_valid; ++j) {
1843                         __be64 hpte_v;
1844                         __be64 hpte_r;
1845
1846                         err = -EFAULT;
1847                         if (__get_user(hpte_v, lbuf) ||
1848                             __get_user(hpte_r, lbuf + 1))
1849                                 goto out;
1850                         v = be64_to_cpu(hpte_v);
1851                         r = be64_to_cpu(hpte_r);
1852                         err = -EINVAL;
1853                         if (!(v & HPTE_V_VALID))
1854                                 goto out;
1855                         lbuf += 2;
1856                         nb += HPTE_SIZE;
1857
1858                         if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT))
1859                                 kvmppc_do_h_remove(kvm, 0, i, 0, tmp);
1860                         err = -EIO;
1861                         ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, i, v, r,
1862                                                          tmp);
1863                         if (ret != H_SUCCESS) {
1864                                 pr_err("kvm_htab_write ret %ld i=%ld v=%lx "
1865                                        "r=%lx\n", ret, i, v, r);
1866                                 goto out;
1867                         }
1868                         if (!hpte_setup && is_vrma_hpte(v)) {
1869                                 unsigned long psize = hpte_base_page_size(v, r);
1870                                 unsigned long senc = slb_pgsize_encoding(psize);
1871                                 unsigned long lpcr;
1872
1873                                 kvm->arch.vrma_slb_v = senc | SLB_VSID_B_1T |
1874                                         (VRMA_VSID << SLB_VSID_SHIFT_1T);
1875                                 lpcr = senc << (LPCR_VRMASD_SH - 4);
1876                                 kvmppc_update_lpcr(kvm, lpcr, LPCR_VRMASD);
1877                                 hpte_setup = 1;
1878                         }
1879                         ++i;
1880                         hptp += 2;
1881                 }
1882
1883                 for (j = 0; j < hdr.n_invalid; ++j) {
1884                         if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT))
1885                                 kvmppc_do_h_remove(kvm, 0, i, 0, tmp);
1886                         ++i;
1887                         hptp += 2;
1888                 }
1889                 err = 0;
1890         }
1891
1892  out:
1893         /* Order HPTE updates vs. hpte_setup_done */
1894         smp_wmb();
1895         kvm->arch.hpte_setup_done = hpte_setup;
1896         mutex_unlock(&kvm->lock);
1897
1898         if (err)
1899                 return err;
1900         return nb;
1901 }
1902
1903 static int kvm_htab_release(struct inode *inode, struct file *filp)
1904 {
1905         struct kvm_htab_ctx *ctx = filp->private_data;
1906
1907         filp->private_data = NULL;
1908         if (!(ctx->flags & KVM_GET_HTAB_WRITE))
1909                 atomic_dec(&ctx->kvm->arch.hpte_mod_interest);
1910         kvm_put_kvm(ctx->kvm);
1911         kfree(ctx);
1912         return 0;
1913 }
1914
1915 static const struct file_operations kvm_htab_fops = {
1916         .read           = kvm_htab_read,
1917         .write          = kvm_htab_write,
1918         .llseek         = default_llseek,
1919         .release        = kvm_htab_release,
1920 };
1921
1922 int kvm_vm_ioctl_get_htab_fd(struct kvm *kvm, struct kvm_get_htab_fd *ghf)
1923 {
1924         int ret;
1925         struct kvm_htab_ctx *ctx;
1926         int rwflag;
1927
1928         /* reject flags we don't recognize */
1929         if (ghf->flags & ~(KVM_GET_HTAB_BOLTED_ONLY | KVM_GET_HTAB_WRITE))
1930                 return -EINVAL;
1931         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1932         if (!ctx)
1933                 return -ENOMEM;
1934         kvm_get_kvm(kvm);
1935         ctx->kvm = kvm;
1936         ctx->index = ghf->start_index;
1937         ctx->flags = ghf->flags;
1938         ctx->first_pass = 1;
1939
1940         rwflag = (ghf->flags & KVM_GET_HTAB_WRITE) ? O_WRONLY : O_RDONLY;
1941         ret = anon_inode_getfd("kvm-htab", &kvm_htab_fops, ctx, rwflag | O_CLOEXEC);
1942         if (ret < 0) {
1943                 kvm_put_kvm(kvm);
1944                 return ret;
1945         }
1946
1947         if (rwflag == O_RDONLY) {
1948                 mutex_lock(&kvm->slots_lock);
1949                 atomic_inc(&kvm->arch.hpte_mod_interest);
1950                 /* make sure kvmppc_do_h_enter etc. see the increment */
1951                 synchronize_srcu_expedited(&kvm->srcu);
1952                 mutex_unlock(&kvm->slots_lock);
1953         }
1954
1955         return ret;
1956 }
1957
1958 struct debugfs_htab_state {
1959         struct kvm      *kvm;
1960         struct mutex    mutex;
1961         unsigned long   hpt_index;
1962         int             chars_left;
1963         int             buf_index;
1964         char            buf[64];
1965 };
1966
1967 static int debugfs_htab_open(struct inode *inode, struct file *file)
1968 {
1969         struct kvm *kvm = inode->i_private;
1970         struct debugfs_htab_state *p;
1971
1972         p = kzalloc(sizeof(*p), GFP_KERNEL);
1973         if (!p)
1974                 return -ENOMEM;
1975
1976         kvm_get_kvm(kvm);
1977         p->kvm = kvm;
1978         mutex_init(&p->mutex);
1979         file->private_data = p;
1980
1981         return nonseekable_open(inode, file);
1982 }
1983
1984 static int debugfs_htab_release(struct inode *inode, struct file *file)
1985 {
1986         struct debugfs_htab_state *p = file->private_data;
1987
1988         kvm_put_kvm(p->kvm);
1989         kfree(p);
1990         return 0;
1991 }
1992
1993 static ssize_t debugfs_htab_read(struct file *file, char __user *buf,
1994                                  size_t len, loff_t *ppos)
1995 {
1996         struct debugfs_htab_state *p = file->private_data;
1997         ssize_t ret, r;
1998         unsigned long i, n;
1999         unsigned long v, hr, gr;
2000         struct kvm *kvm;
2001         __be64 *hptp;
2002
2003         ret = mutex_lock_interruptible(&p->mutex);
2004         if (ret)
2005                 return ret;
2006
2007         if (p->chars_left) {
2008                 n = p->chars_left;
2009                 if (n > len)
2010                         n = len;
2011                 r = copy_to_user(buf, p->buf + p->buf_index, n);
2012                 n -= r;
2013                 p->chars_left -= n;
2014                 p->buf_index += n;
2015                 buf += n;
2016                 len -= n;
2017                 ret = n;
2018                 if (r) {
2019                         if (!n)
2020                                 ret = -EFAULT;
2021                         goto out;
2022                 }
2023         }
2024
2025         kvm = p->kvm;
2026         i = p->hpt_index;
2027         hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
2028         for (; len != 0 && i < kvmppc_hpt_npte(&kvm->arch.hpt);
2029              ++i, hptp += 2) {
2030                 if (!(be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)))
2031                         continue;
2032
2033                 /* lock the HPTE so it's stable and read it */
2034                 preempt_disable();
2035                 while (!try_lock_hpte(hptp, HPTE_V_HVLOCK))
2036                         cpu_relax();
2037                 v = be64_to_cpu(hptp[0]) & ~HPTE_V_HVLOCK;
2038                 hr = be64_to_cpu(hptp[1]);
2039                 gr = kvm->arch.hpt.rev[i].guest_rpte;
2040                 unlock_hpte(hptp, v);
2041                 preempt_enable();
2042
2043                 if (!(v & (HPTE_V_VALID | HPTE_V_ABSENT)))
2044                         continue;
2045
2046                 n = scnprintf(p->buf, sizeof(p->buf),
2047                               "%6lx %.16lx %.16lx %.16lx\n",
2048                               i, v, hr, gr);
2049                 p->chars_left = n;
2050                 if (n > len)
2051                         n = len;
2052                 r = copy_to_user(buf, p->buf, n);
2053                 n -= r;
2054                 p->chars_left -= n;
2055                 p->buf_index = n;
2056                 buf += n;
2057                 len -= n;
2058                 ret += n;
2059                 if (r) {
2060                         if (!ret)
2061                                 ret = -EFAULT;
2062                         goto out;
2063                 }
2064         }
2065         p->hpt_index = i;
2066
2067  out:
2068         mutex_unlock(&p->mutex);
2069         return ret;
2070 }
2071
2072 static ssize_t debugfs_htab_write(struct file *file, const char __user *buf,
2073                            size_t len, loff_t *ppos)
2074 {
2075         return -EACCES;
2076 }
2077
2078 static const struct file_operations debugfs_htab_fops = {
2079         .owner   = THIS_MODULE,
2080         .open    = debugfs_htab_open,
2081         .release = debugfs_htab_release,
2082         .read    = debugfs_htab_read,
2083         .write   = debugfs_htab_write,
2084         .llseek  = generic_file_llseek,
2085 };
2086
2087 void kvmppc_mmu_debugfs_init(struct kvm *kvm)
2088 {
2089         kvm->arch.htab_dentry = debugfs_create_file("htab", 0400,
2090                                                     kvm->arch.debugfs_dir, kvm,
2091                                                     &debugfs_htab_fops);
2092 }
2093
2094 void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu)
2095 {
2096         struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
2097
2098         vcpu->arch.slb_nr = 32;         /* POWER7/POWER8 */
2099
2100         if (kvm_is_radix(vcpu->kvm))
2101                 mmu->xlate = kvmppc_mmu_radix_xlate;
2102         else
2103                 mmu->xlate = kvmppc_mmu_book3s_64_hv_xlate;
2104         mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr;
2105
2106         vcpu->arch.hflags |= BOOK3S_HFLAG_SLB;
2107 }