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/kvm_ppc.h> 33 #include <asm/kvm_book3s.h> 34 #include <asm/book3s/64/mmu-hash.h> 35 #include <asm/hvcall.h> 36 #include <asm/synch.h> 37 #include <asm/ppc-opcode.h> 38 #include <asm/cputable.h> 39 #include <asm/pte-walk.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 68 /* Possible values and their usage: 69 * <0 an error occurred during allocation, 70 * -EBUSY allocation is in the progress, 71 * 0 allocation made successfuly. 72 */ 73 int error; 74 75 /* Private to the work thread, until error != -EBUSY, 76 * then protected by kvm->lock. 77 */ 78 struct kvm_hpt_info hpt; 79 }; 80 81 int kvmppc_allocate_hpt(struct kvm_hpt_info *info, u32 order) 82 { 83 unsigned long hpt = 0; 84 int cma = 0; 85 struct page *page = NULL; 86 struct revmap_entry *rev; 87 unsigned long npte; 88 89 if ((order < PPC_MIN_HPT_ORDER) || (order > PPC_MAX_HPT_ORDER)) 90 return -EINVAL; 91 92 page = kvm_alloc_hpt_cma(1ul << (order - PAGE_SHIFT)); 93 if (page) { 94 hpt = (unsigned long)pfn_to_kaddr(page_to_pfn(page)); 95 memset((void *)hpt, 0, (1ul << order)); 96 cma = 1; 97 } 98 99 if (!hpt) 100 hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL 101 |__GFP_NOWARN, order - PAGE_SHIFT); 102 103 if (!hpt) 104 return -ENOMEM; 105 106 /* HPTEs are 2**4 bytes long */ 107 npte = 1ul << (order - 4); 108 109 /* Allocate reverse map array */ 110 rev = vmalloc(array_size(npte, sizeof(struct revmap_entry))); 111 if (!rev) { 112 if (cma) 113 kvm_free_hpt_cma(page, 1 << (order - PAGE_SHIFT)); 114 else 115 free_pages(hpt, order - PAGE_SHIFT); 116 return -ENOMEM; 117 } 118 119 info->order = order; 120 info->virt = hpt; 121 info->cma = cma; 122 info->rev = rev; 123 124 return 0; 125 } 126 127 void kvmppc_set_hpt(struct kvm *kvm, struct kvm_hpt_info *info) 128 { 129 atomic64_set(&kvm->arch.mmio_update, 0); 130 kvm->arch.hpt = *info; 131 kvm->arch.sdr1 = __pa(info->virt) | (info->order - 18); 132 133 pr_debug("KVM guest htab at %lx (order %ld), LPID %x\n", 134 info->virt, (long)info->order, kvm->arch.lpid); 135 } 136 137 long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order) 138 { 139 long err = -EBUSY; 140 struct kvm_hpt_info info; 141 142 mutex_lock(&kvm->lock); 143 if (kvm->arch.mmu_ready) { 144 kvm->arch.mmu_ready = 0; 145 /* order mmu_ready vs. vcpus_running */ 146 smp_mb(); 147 if (atomic_read(&kvm->arch.vcpus_running)) { 148 kvm->arch.mmu_ready = 1; 149 goto out; 150 } 151 } 152 if (kvm_is_radix(kvm)) { 153 err = kvmppc_switch_mmu_to_hpt(kvm); 154 if (err) 155 goto out; 156 } 157 158 if (kvm->arch.hpt.order == order) { 159 /* We already have a suitable HPT */ 160 161 /* Set the entire HPT to 0, i.e. invalid HPTEs */ 162 memset((void *)kvm->arch.hpt.virt, 0, 1ul << order); 163 /* 164 * Reset all the reverse-mapping chains for all memslots 165 */ 166 kvmppc_rmap_reset(kvm); 167 err = 0; 168 goto out; 169 } 170 171 if (kvm->arch.hpt.virt) { 172 kvmppc_free_hpt(&kvm->arch.hpt); 173 kvmppc_rmap_reset(kvm); 174 } 175 176 err = kvmppc_allocate_hpt(&info, order); 177 if (err < 0) 178 goto out; 179 kvmppc_set_hpt(kvm, &info); 180 181 out: 182 if (err == 0) 183 /* Ensure that each vcpu will flush its TLB on next entry. */ 184 cpumask_setall(&kvm->arch.need_tlb_flush); 185 186 mutex_unlock(&kvm->lock); 187 return err; 188 } 189 190 void kvmppc_free_hpt(struct kvm_hpt_info *info) 191 { 192 vfree(info->rev); 193 info->rev = NULL; 194 if (info->cma) 195 kvm_free_hpt_cma(virt_to_page(info->virt), 196 1 << (info->order - PAGE_SHIFT)); 197 else if (info->virt) 198 free_pages(info->virt, info->order - PAGE_SHIFT); 199 info->virt = 0; 200 info->order = 0; 201 } 202 203 /* Bits in first HPTE dword for pagesize 4k, 64k or 16M */ 204 static inline unsigned long hpte0_pgsize_encoding(unsigned long pgsize) 205 { 206 return (pgsize > 0x1000) ? HPTE_V_LARGE : 0; 207 } 208 209 /* Bits in second HPTE dword for pagesize 4k, 64k or 16M */ 210 static inline unsigned long hpte1_pgsize_encoding(unsigned long pgsize) 211 { 212 return (pgsize == 0x10000) ? 0x1000 : 0; 213 } 214 215 void kvmppc_map_vrma(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot, 216 unsigned long porder) 217 { 218 unsigned long i; 219 unsigned long npages; 220 unsigned long hp_v, hp_r; 221 unsigned long addr, hash; 222 unsigned long psize; 223 unsigned long hp0, hp1; 224 unsigned long idx_ret; 225 long ret; 226 struct kvm *kvm = vcpu->kvm; 227 228 psize = 1ul << porder; 229 npages = memslot->npages >> (porder - PAGE_SHIFT); 230 231 /* VRMA can't be > 1TB */ 232 if (npages > 1ul << (40 - porder)) 233 npages = 1ul << (40 - porder); 234 /* Can't use more than 1 HPTE per HPTEG */ 235 if (npages > kvmppc_hpt_mask(&kvm->arch.hpt) + 1) 236 npages = kvmppc_hpt_mask(&kvm->arch.hpt) + 1; 237 238 hp0 = HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)) | 239 HPTE_V_BOLTED | hpte0_pgsize_encoding(psize); 240 hp1 = hpte1_pgsize_encoding(psize) | 241 HPTE_R_R | HPTE_R_C | HPTE_R_M | PP_RWXX; 242 243 for (i = 0; i < npages; ++i) { 244 addr = i << porder; 245 /* can't use hpt_hash since va > 64 bits */ 246 hash = (i ^ (VRMA_VSID ^ (VRMA_VSID << 25))) 247 & kvmppc_hpt_mask(&kvm->arch.hpt); 248 /* 249 * We assume that the hash table is empty and no 250 * vcpus are using it at this stage. Since we create 251 * at most one HPTE per HPTEG, we just assume entry 7 252 * is available and use it. 253 */ 254 hash = (hash << 3) + 7; 255 hp_v = hp0 | ((addr >> 16) & ~0x7fUL); 256 hp_r = hp1 | addr; 257 ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, hash, hp_v, hp_r, 258 &idx_ret); 259 if (ret != H_SUCCESS) { 260 pr_err("KVM: map_vrma at %lx failed, ret=%ld\n", 261 addr, ret); 262 break; 263 } 264 } 265 } 266 267 int kvmppc_mmu_hv_init(void) 268 { 269 unsigned long host_lpid, rsvd_lpid; 270 271 if (!mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE)) 272 return -EINVAL; 273 274 /* POWER7 has 10-bit LPIDs (12-bit in POWER8) */ 275 host_lpid = 0; 276 if (cpu_has_feature(CPU_FTR_HVMODE)) 277 host_lpid = mfspr(SPRN_LPID); 278 rsvd_lpid = LPID_RSVD; 279 280 kvmppc_init_lpid(rsvd_lpid + 1); 281 282 kvmppc_claim_lpid(host_lpid); 283 /* rsvd_lpid is reserved for use in partition switching */ 284 kvmppc_claim_lpid(rsvd_lpid); 285 286 return 0; 287 } 288 289 static void kvmppc_mmu_book3s_64_hv_reset_msr(struct kvm_vcpu *vcpu) 290 { 291 unsigned long msr = vcpu->arch.intr_msr; 292 293 /* If transactional, change to suspend mode on IRQ delivery */ 294 if (MSR_TM_TRANSACTIONAL(vcpu->arch.shregs.msr)) 295 msr |= MSR_TS_S; 296 else 297 msr |= vcpu->arch.shregs.msr & MSR_TS_MASK; 298 kvmppc_set_msr(vcpu, msr); 299 } 300 301 static long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags, 302 long pte_index, unsigned long pteh, 303 unsigned long ptel, unsigned long *pte_idx_ret) 304 { 305 long ret; 306 307 /* Protect linux PTE lookup from page table destruction */ 308 rcu_read_lock_sched(); /* this disables preemption too */ 309 ret = kvmppc_do_h_enter(kvm, flags, pte_index, pteh, ptel, 310 current->mm->pgd, false, pte_idx_ret); 311 rcu_read_unlock_sched(); 312 if (ret == H_TOO_HARD) { 313 /* this can't happen */ 314 pr_err("KVM: Oops, kvmppc_h_enter returned too hard!\n"); 315 ret = H_RESOURCE; /* or something */ 316 } 317 return ret; 318 319 } 320 321 static struct kvmppc_slb *kvmppc_mmu_book3s_hv_find_slbe(struct kvm_vcpu *vcpu, 322 gva_t eaddr) 323 { 324 u64 mask; 325 int i; 326 327 for (i = 0; i < vcpu->arch.slb_nr; i++) { 328 if (!(vcpu->arch.slb[i].orige & SLB_ESID_V)) 329 continue; 330 331 if (vcpu->arch.slb[i].origv & SLB_VSID_B_1T) 332 mask = ESID_MASK_1T; 333 else 334 mask = ESID_MASK; 335 336 if (((vcpu->arch.slb[i].orige ^ eaddr) & mask) == 0) 337 return &vcpu->arch.slb[i]; 338 } 339 return NULL; 340 } 341 342 static unsigned long kvmppc_mmu_get_real_addr(unsigned long v, unsigned long r, 343 unsigned long ea) 344 { 345 unsigned long ra_mask; 346 347 ra_mask = kvmppc_actual_pgsz(v, r) - 1; 348 return (r & HPTE_R_RPN & ~ra_mask) | (ea & ra_mask); 349 } 350 351 static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, 352 struct kvmppc_pte *gpte, bool data, bool iswrite) 353 { 354 struct kvm *kvm = vcpu->kvm; 355 struct kvmppc_slb *slbe; 356 unsigned long slb_v; 357 unsigned long pp, key; 358 unsigned long v, orig_v, gr; 359 __be64 *hptep; 360 long int index; 361 int virtmode = vcpu->arch.shregs.msr & (data ? MSR_DR : MSR_IR); 362 363 if (kvm_is_radix(vcpu->kvm)) 364 return kvmppc_mmu_radix_xlate(vcpu, eaddr, gpte, data, iswrite); 365 366 /* Get SLB entry */ 367 if (virtmode) { 368 slbe = kvmppc_mmu_book3s_hv_find_slbe(vcpu, eaddr); 369 if (!slbe) 370 return -EINVAL; 371 slb_v = slbe->origv; 372 } else { 373 /* real mode access */ 374 slb_v = vcpu->kvm->arch.vrma_slb_v; 375 } 376 377 preempt_disable(); 378 /* Find the HPTE in the hash table */ 379 index = kvmppc_hv_find_lock_hpte(kvm, eaddr, slb_v, 380 HPTE_V_VALID | HPTE_V_ABSENT); 381 if (index < 0) { 382 preempt_enable(); 383 return -ENOENT; 384 } 385 hptep = (__be64 *)(kvm->arch.hpt.virt + (index << 4)); 386 v = orig_v = be64_to_cpu(hptep[0]) & ~HPTE_V_HVLOCK; 387 if (cpu_has_feature(CPU_FTR_ARCH_300)) 388 v = hpte_new_to_old_v(v, be64_to_cpu(hptep[1])); 389 gr = kvm->arch.hpt.rev[index].guest_rpte; 390 391 unlock_hpte(hptep, orig_v); 392 preempt_enable(); 393 394 gpte->eaddr = eaddr; 395 gpte->vpage = ((v & HPTE_V_AVPN) << 4) | ((eaddr >> 12) & 0xfff); 396 397 /* Get PP bits and key for permission check */ 398 pp = gr & (HPTE_R_PP0 | HPTE_R_PP); 399 key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS; 400 key &= slb_v; 401 402 /* Calculate permissions */ 403 gpte->may_read = hpte_read_permission(pp, key); 404 gpte->may_write = hpte_write_permission(pp, key); 405 gpte->may_execute = gpte->may_read && !(gr & (HPTE_R_N | HPTE_R_G)); 406 407 /* Storage key permission check for POWER7 */ 408 if (data && virtmode) { 409 int amrfield = hpte_get_skey_perm(gr, vcpu->arch.amr); 410 if (amrfield & 1) 411 gpte->may_read = 0; 412 if (amrfield & 2) 413 gpte->may_write = 0; 414 } 415 416 /* Get the guest physical address */ 417 gpte->raddr = kvmppc_mmu_get_real_addr(v, gr, eaddr); 418 return 0; 419 } 420 421 /* 422 * Quick test for whether an instruction is a load or a store. 423 * If the instruction is a load or a store, then this will indicate 424 * which it is, at least on server processors. (Embedded processors 425 * have some external PID instructions that don't follow the rule 426 * embodied here.) If the instruction isn't a load or store, then 427 * this doesn't return anything useful. 428 */ 429 static int instruction_is_store(unsigned int instr) 430 { 431 unsigned int mask; 432 433 mask = 0x10000000; 434 if ((instr & 0xfc000000) == 0x7c000000) 435 mask = 0x100; /* major opcode 31 */ 436 return (instr & mask) != 0; 437 } 438 439 int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu, 440 unsigned long gpa, gva_t ea, int is_store) 441 { 442 u32 last_inst; 443 444 /* 445 * Fast path - check if the guest physical address corresponds to a 446 * device on the FAST_MMIO_BUS, if so we can avoid loading the 447 * instruction all together, then we can just handle it and return. 448 */ 449 if (is_store) { 450 int idx, ret; 451 452 idx = srcu_read_lock(&vcpu->kvm->srcu); 453 ret = kvm_io_bus_write(vcpu, KVM_FAST_MMIO_BUS, (gpa_t) gpa, 0, 454 NULL); 455 srcu_read_unlock(&vcpu->kvm->srcu, idx); 456 if (!ret) { 457 kvmppc_set_pc(vcpu, kvmppc_get_pc(vcpu) + 4); 458 return RESUME_GUEST; 459 } 460 } 461 462 /* 463 * If we fail, we just return to the guest and try executing it again. 464 */ 465 if (kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst) != 466 EMULATE_DONE) 467 return RESUME_GUEST; 468 469 /* 470 * WARNING: We do not know for sure whether the instruction we just 471 * read from memory is the same that caused the fault in the first 472 * place. If the instruction we read is neither an load or a store, 473 * then it can't access memory, so we don't need to worry about 474 * enforcing access permissions. So, assuming it is a load or 475 * store, we just check that its direction (load or store) is 476 * consistent with the original fault, since that's what we 477 * checked the access permissions against. If there is a mismatch 478 * we just return and retry the instruction. 479 */ 480 481 if (instruction_is_store(last_inst) != !!is_store) 482 return RESUME_GUEST; 483 484 /* 485 * Emulated accesses are emulated by looking at the hash for 486 * translation once, then performing the access later. The 487 * translation could be invalidated in the meantime in which 488 * point performing the subsequent memory access on the old 489 * physical address could possibly be a security hole for the 490 * guest (but not the host). 491 * 492 * This is less of an issue for MMIO stores since they aren't 493 * globally visible. It could be an issue for MMIO loads to 494 * a certain extent but we'll ignore it for now. 495 */ 496 497 vcpu->arch.paddr_accessed = gpa; 498 vcpu->arch.vaddr_accessed = ea; 499 return kvmppc_emulate_mmio(run, vcpu); 500 } 501 502 int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, 503 unsigned long ea, unsigned long dsisr) 504 { 505 struct kvm *kvm = vcpu->kvm; 506 unsigned long hpte[3], r; 507 unsigned long hnow_v, hnow_r; 508 __be64 *hptep; 509 unsigned long mmu_seq, psize, pte_size; 510 unsigned long gpa_base, gfn_base; 511 unsigned long gpa, gfn, hva, pfn; 512 struct kvm_memory_slot *memslot; 513 unsigned long *rmap; 514 struct revmap_entry *rev; 515 struct page *page, *pages[1]; 516 long index, ret, npages; 517 bool is_ci; 518 unsigned int writing, write_ok; 519 struct vm_area_struct *vma; 520 unsigned long rcbits; 521 long mmio_update; 522 523 if (kvm_is_radix(kvm)) 524 return kvmppc_book3s_radix_page_fault(run, vcpu, ea, dsisr); 525 526 /* 527 * Real-mode code has already searched the HPT and found the 528 * entry we're interested in. Lock the entry and check that 529 * it hasn't changed. If it has, just return and re-execute the 530 * instruction. 531 */ 532 if (ea != vcpu->arch.pgfault_addr) 533 return RESUME_GUEST; 534 535 if (vcpu->arch.pgfault_cache) { 536 mmio_update = atomic64_read(&kvm->arch.mmio_update); 537 if (mmio_update == vcpu->arch.pgfault_cache->mmio_update) { 538 r = vcpu->arch.pgfault_cache->rpte; 539 psize = kvmppc_actual_pgsz(vcpu->arch.pgfault_hpte[0], 540 r); 541 gpa_base = r & HPTE_R_RPN & ~(psize - 1); 542 gfn_base = gpa_base >> PAGE_SHIFT; 543 gpa = gpa_base | (ea & (psize - 1)); 544 return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea, 545 dsisr & DSISR_ISSTORE); 546 } 547 } 548 index = vcpu->arch.pgfault_index; 549 hptep = (__be64 *)(kvm->arch.hpt.virt + (index << 4)); 550 rev = &kvm->arch.hpt.rev[index]; 551 preempt_disable(); 552 while (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) 553 cpu_relax(); 554 hpte[0] = be64_to_cpu(hptep[0]) & ~HPTE_V_HVLOCK; 555 hpte[1] = be64_to_cpu(hptep[1]); 556 hpte[2] = r = rev->guest_rpte; 557 unlock_hpte(hptep, hpte[0]); 558 preempt_enable(); 559 560 if (cpu_has_feature(CPU_FTR_ARCH_300)) { 561 hpte[0] = hpte_new_to_old_v(hpte[0], hpte[1]); 562 hpte[1] = hpte_new_to_old_r(hpte[1]); 563 } 564 if (hpte[0] != vcpu->arch.pgfault_hpte[0] || 565 hpte[1] != vcpu->arch.pgfault_hpte[1]) 566 return RESUME_GUEST; 567 568 /* Translate the logical address and get the page */ 569 psize = kvmppc_actual_pgsz(hpte[0], r); 570 gpa_base = r & HPTE_R_RPN & ~(psize - 1); 571 gfn_base = gpa_base >> PAGE_SHIFT; 572 gpa = gpa_base | (ea & (psize - 1)); 573 gfn = gpa >> PAGE_SHIFT; 574 memslot = gfn_to_memslot(kvm, gfn); 575 576 trace_kvm_page_fault_enter(vcpu, hpte, memslot, ea, dsisr); 577 578 /* No memslot means it's an emulated MMIO region */ 579 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) 580 return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea, 581 dsisr & DSISR_ISSTORE); 582 583 /* 584 * This should never happen, because of the slot_is_aligned() 585 * check in kvmppc_do_h_enter(). 586 */ 587 if (gfn_base < memslot->base_gfn) 588 return -EFAULT; 589 590 /* used to check for invalidations in progress */ 591 mmu_seq = kvm->mmu_notifier_seq; 592 smp_rmb(); 593 594 ret = -EFAULT; 595 is_ci = false; 596 pfn = 0; 597 page = NULL; 598 pte_size = PAGE_SIZE; 599 writing = (dsisr & DSISR_ISSTORE) != 0; 600 /* If writing != 0, then the HPTE must allow writing, if we get here */ 601 write_ok = writing; 602 hva = gfn_to_hva_memslot(memslot, gfn); 603 npages = get_user_pages_fast(hva, 1, writing, pages); 604 if (npages < 1) { 605 /* Check if it's an I/O mapping */ 606 down_read(¤t->mm->mmap_sem); 607 vma = find_vma(current->mm, hva); 608 if (vma && vma->vm_start <= hva && hva + psize <= vma->vm_end && 609 (vma->vm_flags & VM_PFNMAP)) { 610 pfn = vma->vm_pgoff + 611 ((hva - vma->vm_start) >> PAGE_SHIFT); 612 pte_size = psize; 613 is_ci = pte_ci(__pte((pgprot_val(vma->vm_page_prot)))); 614 write_ok = vma->vm_flags & VM_WRITE; 615 } 616 up_read(¤t->mm->mmap_sem); 617 if (!pfn) 618 goto out_put; 619 } else { 620 page = pages[0]; 621 pfn = page_to_pfn(page); 622 if (PageHuge(page)) { 623 page = compound_head(page); 624 pte_size <<= compound_order(page); 625 } 626 /* if the guest wants write access, see if that is OK */ 627 if (!writing && hpte_is_writable(r)) { 628 pte_t *ptep, pte; 629 unsigned long flags; 630 /* 631 * We need to protect against page table destruction 632 * hugepage split and collapse. 633 */ 634 local_irq_save(flags); 635 ptep = find_current_mm_pte(current->mm->pgd, 636 hva, NULL, NULL); 637 if (ptep) { 638 pte = kvmppc_read_update_linux_pte(ptep, 1); 639 if (__pte_write(pte)) 640 write_ok = 1; 641 } 642 local_irq_restore(flags); 643 } 644 } 645 646 if (psize > pte_size) 647 goto out_put; 648 649 /* Check WIMG vs. the actual page we're accessing */ 650 if (!hpte_cache_flags_ok(r, is_ci)) { 651 if (is_ci) 652 goto out_put; 653 /* 654 * Allow guest to map emulated device memory as 655 * uncacheable, but actually make it cacheable. 656 */ 657 r = (r & ~(HPTE_R_W|HPTE_R_I|HPTE_R_G)) | HPTE_R_M; 658 } 659 660 /* 661 * Set the HPTE to point to pfn. 662 * Since the pfn is at PAGE_SIZE granularity, make sure we 663 * don't mask out lower-order bits if psize < PAGE_SIZE. 664 */ 665 if (psize < PAGE_SIZE) 666 psize = PAGE_SIZE; 667 r = (r & HPTE_R_KEY_HI) | (r & ~(HPTE_R_PP0 - psize)) | 668 ((pfn << PAGE_SHIFT) & ~(psize - 1)); 669 if (hpte_is_writable(r) && !write_ok) 670 r = hpte_make_readonly(r); 671 ret = RESUME_GUEST; 672 preempt_disable(); 673 while (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) 674 cpu_relax(); 675 hnow_v = be64_to_cpu(hptep[0]); 676 hnow_r = be64_to_cpu(hptep[1]); 677 if (cpu_has_feature(CPU_FTR_ARCH_300)) { 678 hnow_v = hpte_new_to_old_v(hnow_v, hnow_r); 679 hnow_r = hpte_new_to_old_r(hnow_r); 680 } 681 682 /* 683 * If the HPT is being resized, don't update the HPTE, 684 * instead let the guest retry after the resize operation is complete. 685 * The synchronization for mmu_ready test vs. set is provided 686 * by the HPTE lock. 687 */ 688 if (!kvm->arch.mmu_ready) 689 goto out_unlock; 690 691 if ((hnow_v & ~HPTE_V_HVLOCK) != hpte[0] || hnow_r != hpte[1] || 692 rev->guest_rpte != hpte[2]) 693 /* HPTE has been changed under us; let the guest retry */ 694 goto out_unlock; 695 hpte[0] = (hpte[0] & ~HPTE_V_ABSENT) | HPTE_V_VALID; 696 697 /* Always put the HPTE in the rmap chain for the page base address */ 698 rmap = &memslot->arch.rmap[gfn_base - memslot->base_gfn]; 699 lock_rmap(rmap); 700 701 /* Check if we might have been invalidated; let the guest retry if so */ 702 ret = RESUME_GUEST; 703 if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) { 704 unlock_rmap(rmap); 705 goto out_unlock; 706 } 707 708 /* Only set R/C in real HPTE if set in both *rmap and guest_rpte */ 709 rcbits = *rmap >> KVMPPC_RMAP_RC_SHIFT; 710 r &= rcbits | ~(HPTE_R_R | HPTE_R_C); 711 712 if (be64_to_cpu(hptep[0]) & HPTE_V_VALID) { 713 /* HPTE was previously valid, so we need to invalidate it */ 714 unlock_rmap(rmap); 715 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT); 716 kvmppc_invalidate_hpte(kvm, hptep, index); 717 /* don't lose previous R and C bits */ 718 r |= be64_to_cpu(hptep[1]) & (HPTE_R_R | HPTE_R_C); 719 } else { 720 kvmppc_add_revmap_chain(kvm, rev, rmap, index, 0); 721 } 722 723 if (cpu_has_feature(CPU_FTR_ARCH_300)) { 724 r = hpte_old_to_new_r(hpte[0], r); 725 hpte[0] = hpte_old_to_new_v(hpte[0]); 726 } 727 hptep[1] = cpu_to_be64(r); 728 eieio(); 729 __unlock_hpte(hptep, hpte[0]); 730 asm volatile("ptesync" : : : "memory"); 731 preempt_enable(); 732 if (page && hpte_is_writable(r)) 733 SetPageDirty(page); 734 735 out_put: 736 trace_kvm_page_fault_exit(vcpu, hpte, ret); 737 738 if (page) { 739 /* 740 * We drop pages[0] here, not page because page might 741 * have been set to the head page of a compound, but 742 * we have to drop the reference on the correct tail 743 * page to match the get inside gup() 744 */ 745 put_page(pages[0]); 746 } 747 return ret; 748 749 out_unlock: 750 __unlock_hpte(hptep, be64_to_cpu(hptep[0])); 751 preempt_enable(); 752 goto out_put; 753 } 754 755 void kvmppc_rmap_reset(struct kvm *kvm) 756 { 757 struct kvm_memslots *slots; 758 struct kvm_memory_slot *memslot; 759 int srcu_idx; 760 761 srcu_idx = srcu_read_lock(&kvm->srcu); 762 slots = kvm_memslots(kvm); 763 kvm_for_each_memslot(memslot, slots) { 764 /* Mutual exclusion with kvm_unmap_hva_range etc. */ 765 spin_lock(&kvm->mmu_lock); 766 /* 767 * This assumes it is acceptable to lose reference and 768 * change bits across a reset. 769 */ 770 memset(memslot->arch.rmap, 0, 771 memslot->npages * sizeof(*memslot->arch.rmap)); 772 spin_unlock(&kvm->mmu_lock); 773 } 774 srcu_read_unlock(&kvm->srcu, srcu_idx); 775 } 776 777 typedef int (*hva_handler_fn)(struct kvm *kvm, struct kvm_memory_slot *memslot, 778 unsigned long gfn); 779 780 static int kvm_handle_hva_range(struct kvm *kvm, 781 unsigned long start, 782 unsigned long end, 783 hva_handler_fn handler) 784 { 785 int ret; 786 int retval = 0; 787 struct kvm_memslots *slots; 788 struct kvm_memory_slot *memslot; 789 790 slots = kvm_memslots(kvm); 791 kvm_for_each_memslot(memslot, slots) { 792 unsigned long hva_start, hva_end; 793 gfn_t gfn, gfn_end; 794 795 hva_start = max(start, memslot->userspace_addr); 796 hva_end = min(end, memslot->userspace_addr + 797 (memslot->npages << PAGE_SHIFT)); 798 if (hva_start >= hva_end) 799 continue; 800 /* 801 * {gfn(page) | page intersects with [hva_start, hva_end)} = 802 * {gfn, gfn+1, ..., gfn_end-1}. 803 */ 804 gfn = hva_to_gfn_memslot(hva_start, memslot); 805 gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot); 806 807 for (; gfn < gfn_end; ++gfn) { 808 ret = handler(kvm, memslot, gfn); 809 retval |= ret; 810 } 811 } 812 813 return retval; 814 } 815 816 static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, 817 hva_handler_fn handler) 818 { 819 return kvm_handle_hva_range(kvm, hva, hva + 1, handler); 820 } 821 822 /* Must be called with both HPTE and rmap locked */ 823 static void kvmppc_unmap_hpte(struct kvm *kvm, unsigned long i, 824 struct kvm_memory_slot *memslot, 825 unsigned long *rmapp, unsigned long gfn) 826 { 827 __be64 *hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4)); 828 struct revmap_entry *rev = kvm->arch.hpt.rev; 829 unsigned long j, h; 830 unsigned long ptel, psize, rcbits; 831 832 j = rev[i].forw; 833 if (j == i) { 834 /* chain is now empty */ 835 *rmapp &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX); 836 } else { 837 /* remove i from chain */ 838 h = rev[i].back; 839 rev[h].forw = j; 840 rev[j].back = h; 841 rev[i].forw = rev[i].back = i; 842 *rmapp = (*rmapp & ~KVMPPC_RMAP_INDEX) | j; 843 } 844 845 /* Now check and modify the HPTE */ 846 ptel = rev[i].guest_rpte; 847 psize = kvmppc_actual_pgsz(be64_to_cpu(hptep[0]), ptel); 848 if ((be64_to_cpu(hptep[0]) & HPTE_V_VALID) && 849 hpte_rpn(ptel, psize) == gfn) { 850 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT); 851 kvmppc_invalidate_hpte(kvm, hptep, i); 852 hptep[1] &= ~cpu_to_be64(HPTE_R_KEY_HI | HPTE_R_KEY_LO); 853 /* Harvest R and C */ 854 rcbits = be64_to_cpu(hptep[1]) & (HPTE_R_R | HPTE_R_C); 855 *rmapp |= rcbits << KVMPPC_RMAP_RC_SHIFT; 856 if ((rcbits & HPTE_R_C) && memslot->dirty_bitmap) 857 kvmppc_update_dirty_map(memslot, gfn, psize); 858 if (rcbits & ~rev[i].guest_rpte) { 859 rev[i].guest_rpte = ptel | rcbits; 860 note_hpte_modification(kvm, &rev[i]); 861 } 862 } 863 } 864 865 static int kvm_unmap_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot, 866 unsigned long gfn) 867 { 868 unsigned long i; 869 __be64 *hptep; 870 unsigned long *rmapp; 871 872 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 873 for (;;) { 874 lock_rmap(rmapp); 875 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) { 876 unlock_rmap(rmapp); 877 break; 878 } 879 880 /* 881 * To avoid an ABBA deadlock with the HPTE lock bit, 882 * we can't spin on the HPTE lock while holding the 883 * rmap chain lock. 884 */ 885 i = *rmapp & KVMPPC_RMAP_INDEX; 886 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4)); 887 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) { 888 /* unlock rmap before spinning on the HPTE lock */ 889 unlock_rmap(rmapp); 890 while (be64_to_cpu(hptep[0]) & HPTE_V_HVLOCK) 891 cpu_relax(); 892 continue; 893 } 894 895 kvmppc_unmap_hpte(kvm, i, memslot, rmapp, gfn); 896 unlock_rmap(rmapp); 897 __unlock_hpte(hptep, be64_to_cpu(hptep[0])); 898 } 899 return 0; 900 } 901 902 int kvm_unmap_hva_range_hv(struct kvm *kvm, unsigned long start, unsigned long end) 903 { 904 hva_handler_fn handler; 905 906 handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp; 907 kvm_handle_hva_range(kvm, start, end, handler); 908 return 0; 909 } 910 911 void kvmppc_core_flush_memslot_hv(struct kvm *kvm, 912 struct kvm_memory_slot *memslot) 913 { 914 unsigned long gfn; 915 unsigned long n; 916 unsigned long *rmapp; 917 918 gfn = memslot->base_gfn; 919 rmapp = memslot->arch.rmap; 920 if (kvm_is_radix(kvm)) { 921 kvmppc_radix_flush_memslot(kvm, memslot); 922 return; 923 } 924 925 for (n = memslot->npages; n; --n, ++gfn) { 926 /* 927 * Testing the present bit without locking is OK because 928 * the memslot has been marked invalid already, and hence 929 * no new HPTEs referencing this page can be created, 930 * thus the present bit can't go from 0 to 1. 931 */ 932 if (*rmapp & KVMPPC_RMAP_PRESENT) 933 kvm_unmap_rmapp(kvm, memslot, gfn); 934 ++rmapp; 935 } 936 } 937 938 static int kvm_age_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot, 939 unsigned long gfn) 940 { 941 struct revmap_entry *rev = kvm->arch.hpt.rev; 942 unsigned long head, i, j; 943 __be64 *hptep; 944 int ret = 0; 945 unsigned long *rmapp; 946 947 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 948 retry: 949 lock_rmap(rmapp); 950 if (*rmapp & KVMPPC_RMAP_REFERENCED) { 951 *rmapp &= ~KVMPPC_RMAP_REFERENCED; 952 ret = 1; 953 } 954 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) { 955 unlock_rmap(rmapp); 956 return ret; 957 } 958 959 i = head = *rmapp & KVMPPC_RMAP_INDEX; 960 do { 961 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4)); 962 j = rev[i].forw; 963 964 /* If this HPTE isn't referenced, ignore it */ 965 if (!(be64_to_cpu(hptep[1]) & HPTE_R_R)) 966 continue; 967 968 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) { 969 /* unlock rmap before spinning on the HPTE lock */ 970 unlock_rmap(rmapp); 971 while (be64_to_cpu(hptep[0]) & HPTE_V_HVLOCK) 972 cpu_relax(); 973 goto retry; 974 } 975 976 /* Now check and modify the HPTE */ 977 if ((be64_to_cpu(hptep[0]) & HPTE_V_VALID) && 978 (be64_to_cpu(hptep[1]) & HPTE_R_R)) { 979 kvmppc_clear_ref_hpte(kvm, hptep, i); 980 if (!(rev[i].guest_rpte & HPTE_R_R)) { 981 rev[i].guest_rpte |= HPTE_R_R; 982 note_hpte_modification(kvm, &rev[i]); 983 } 984 ret = 1; 985 } 986 __unlock_hpte(hptep, be64_to_cpu(hptep[0])); 987 } while ((i = j) != head); 988 989 unlock_rmap(rmapp); 990 return ret; 991 } 992 993 int kvm_age_hva_hv(struct kvm *kvm, unsigned long start, unsigned long end) 994 { 995 hva_handler_fn handler; 996 997 handler = kvm_is_radix(kvm) ? kvm_age_radix : kvm_age_rmapp; 998 return kvm_handle_hva_range(kvm, start, end, handler); 999 } 1000 1001 static int kvm_test_age_rmapp(struct kvm *kvm, struct kvm_memory_slot *memslot, 1002 unsigned long gfn) 1003 { 1004 struct revmap_entry *rev = kvm->arch.hpt.rev; 1005 unsigned long head, i, j; 1006 unsigned long *hp; 1007 int ret = 1; 1008 unsigned long *rmapp; 1009 1010 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 1011 if (*rmapp & KVMPPC_RMAP_REFERENCED) 1012 return 1; 1013 1014 lock_rmap(rmapp); 1015 if (*rmapp & KVMPPC_RMAP_REFERENCED) 1016 goto out; 1017 1018 if (*rmapp & KVMPPC_RMAP_PRESENT) { 1019 i = head = *rmapp & KVMPPC_RMAP_INDEX; 1020 do { 1021 hp = (unsigned long *)(kvm->arch.hpt.virt + (i << 4)); 1022 j = rev[i].forw; 1023 if (be64_to_cpu(hp[1]) & HPTE_R_R) 1024 goto out; 1025 } while ((i = j) != head); 1026 } 1027 ret = 0; 1028 1029 out: 1030 unlock_rmap(rmapp); 1031 return ret; 1032 } 1033 1034 int kvm_test_age_hva_hv(struct kvm *kvm, unsigned long hva) 1035 { 1036 hva_handler_fn handler; 1037 1038 handler = kvm_is_radix(kvm) ? kvm_test_age_radix : kvm_test_age_rmapp; 1039 return kvm_handle_hva(kvm, hva, handler); 1040 } 1041 1042 void kvm_set_spte_hva_hv(struct kvm *kvm, unsigned long hva, pte_t pte) 1043 { 1044 hva_handler_fn handler; 1045 1046 handler = kvm_is_radix(kvm) ? kvm_unmap_radix : kvm_unmap_rmapp; 1047 kvm_handle_hva(kvm, hva, handler); 1048 } 1049 1050 static int vcpus_running(struct kvm *kvm) 1051 { 1052 return atomic_read(&kvm->arch.vcpus_running) != 0; 1053 } 1054 1055 /* 1056 * Returns the number of system pages that are dirty. 1057 * This can be more than 1 if we find a huge-page HPTE. 1058 */ 1059 static int kvm_test_clear_dirty_npages(struct kvm *kvm, unsigned long *rmapp) 1060 { 1061 struct revmap_entry *rev = kvm->arch.hpt.rev; 1062 unsigned long head, i, j; 1063 unsigned long n; 1064 unsigned long v, r; 1065 __be64 *hptep; 1066 int npages_dirty = 0; 1067 1068 retry: 1069 lock_rmap(rmapp); 1070 if (!(*rmapp & KVMPPC_RMAP_PRESENT)) { 1071 unlock_rmap(rmapp); 1072 return npages_dirty; 1073 } 1074 1075 i = head = *rmapp & KVMPPC_RMAP_INDEX; 1076 do { 1077 unsigned long hptep1; 1078 hptep = (__be64 *) (kvm->arch.hpt.virt + (i << 4)); 1079 j = rev[i].forw; 1080 1081 /* 1082 * Checking the C (changed) bit here is racy since there 1083 * is no guarantee about when the hardware writes it back. 1084 * If the HPTE is not writable then it is stable since the 1085 * page can't be written to, and we would have done a tlbie 1086 * (which forces the hardware to complete any writeback) 1087 * when making the HPTE read-only. 1088 * If vcpus are running then this call is racy anyway 1089 * since the page could get dirtied subsequently, so we 1090 * expect there to be a further call which would pick up 1091 * any delayed C bit writeback. 1092 * Otherwise we need to do the tlbie even if C==0 in 1093 * order to pick up any delayed writeback of C. 1094 */ 1095 hptep1 = be64_to_cpu(hptep[1]); 1096 if (!(hptep1 & HPTE_R_C) && 1097 (!hpte_is_writable(hptep1) || vcpus_running(kvm))) 1098 continue; 1099 1100 if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) { 1101 /* unlock rmap before spinning on the HPTE lock */ 1102 unlock_rmap(rmapp); 1103 while (hptep[0] & cpu_to_be64(HPTE_V_HVLOCK)) 1104 cpu_relax(); 1105 goto retry; 1106 } 1107 1108 /* Now check and modify the HPTE */ 1109 if (!(hptep[0] & cpu_to_be64(HPTE_V_VALID))) { 1110 __unlock_hpte(hptep, be64_to_cpu(hptep[0])); 1111 continue; 1112 } 1113 1114 /* need to make it temporarily absent so C is stable */ 1115 hptep[0] |= cpu_to_be64(HPTE_V_ABSENT); 1116 kvmppc_invalidate_hpte(kvm, hptep, i); 1117 v = be64_to_cpu(hptep[0]); 1118 r = be64_to_cpu(hptep[1]); 1119 if (r & HPTE_R_C) { 1120 hptep[1] = cpu_to_be64(r & ~HPTE_R_C); 1121 if (!(rev[i].guest_rpte & HPTE_R_C)) { 1122 rev[i].guest_rpte |= HPTE_R_C; 1123 note_hpte_modification(kvm, &rev[i]); 1124 } 1125 n = kvmppc_actual_pgsz(v, r); 1126 n = (n + PAGE_SIZE - 1) >> PAGE_SHIFT; 1127 if (n > npages_dirty) 1128 npages_dirty = n; 1129 eieio(); 1130 } 1131 v &= ~HPTE_V_ABSENT; 1132 v |= HPTE_V_VALID; 1133 __unlock_hpte(hptep, v); 1134 } while ((i = j) != head); 1135 1136 unlock_rmap(rmapp); 1137 return npages_dirty; 1138 } 1139 1140 void kvmppc_harvest_vpa_dirty(struct kvmppc_vpa *vpa, 1141 struct kvm_memory_slot *memslot, 1142 unsigned long *map) 1143 { 1144 unsigned long gfn; 1145 1146 if (!vpa->dirty || !vpa->pinned_addr) 1147 return; 1148 gfn = vpa->gpa >> PAGE_SHIFT; 1149 if (gfn < memslot->base_gfn || 1150 gfn >= memslot->base_gfn + memslot->npages) 1151 return; 1152 1153 vpa->dirty = false; 1154 if (map) 1155 __set_bit_le(gfn - memslot->base_gfn, map); 1156 } 1157 1158 long kvmppc_hv_get_dirty_log_hpt(struct kvm *kvm, 1159 struct kvm_memory_slot *memslot, unsigned long *map) 1160 { 1161 unsigned long i; 1162 unsigned long *rmapp; 1163 1164 preempt_disable(); 1165 rmapp = memslot->arch.rmap; 1166 for (i = 0; i < memslot->npages; ++i) { 1167 int npages = kvm_test_clear_dirty_npages(kvm, rmapp); 1168 /* 1169 * Note that if npages > 0 then i must be a multiple of npages, 1170 * since we always put huge-page HPTEs in the rmap chain 1171 * corresponding to their page base address. 1172 */ 1173 if (npages) 1174 set_dirty_bits(map, i, npages); 1175 ++rmapp; 1176 } 1177 preempt_enable(); 1178 return 0; 1179 } 1180 1181 void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa, 1182 unsigned long *nb_ret) 1183 { 1184 struct kvm_memory_slot *memslot; 1185 unsigned long gfn = gpa >> PAGE_SHIFT; 1186 struct page *page, *pages[1]; 1187 int npages; 1188 unsigned long hva, offset; 1189 int srcu_idx; 1190 1191 srcu_idx = srcu_read_lock(&kvm->srcu); 1192 memslot = gfn_to_memslot(kvm, gfn); 1193 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) 1194 goto err; 1195 hva = gfn_to_hva_memslot(memslot, gfn); 1196 npages = get_user_pages_fast(hva, 1, 1, pages); 1197 if (npages < 1) 1198 goto err; 1199 page = pages[0]; 1200 srcu_read_unlock(&kvm->srcu, srcu_idx); 1201 1202 offset = gpa & (PAGE_SIZE - 1); 1203 if (nb_ret) 1204 *nb_ret = PAGE_SIZE - offset; 1205 return page_address(page) + offset; 1206 1207 err: 1208 srcu_read_unlock(&kvm->srcu, srcu_idx); 1209 return NULL; 1210 } 1211 1212 void kvmppc_unpin_guest_page(struct kvm *kvm, void *va, unsigned long gpa, 1213 bool dirty) 1214 { 1215 struct page *page = virt_to_page(va); 1216 struct kvm_memory_slot *memslot; 1217 unsigned long gfn; 1218 int srcu_idx; 1219 1220 put_page(page); 1221 1222 if (!dirty) 1223 return; 1224 1225 /* We need to mark this page dirty in the memslot dirty_bitmap, if any */ 1226 gfn = gpa >> PAGE_SHIFT; 1227 srcu_idx = srcu_read_lock(&kvm->srcu); 1228 memslot = gfn_to_memslot(kvm, gfn); 1229 if (memslot && memslot->dirty_bitmap) 1230 set_bit_le(gfn - memslot->base_gfn, memslot->dirty_bitmap); 1231 srcu_read_unlock(&kvm->srcu, srcu_idx); 1232 } 1233 1234 /* 1235 * HPT resizing 1236 */ 1237 static int resize_hpt_allocate(struct kvm_resize_hpt *resize) 1238 { 1239 int rc; 1240 1241 rc = kvmppc_allocate_hpt(&resize->hpt, resize->order); 1242 if (rc < 0) 1243 return rc; 1244 1245 resize_hpt_debug(resize, "resize_hpt_allocate(): HPT @ 0x%lx\n", 1246 resize->hpt.virt); 1247 1248 return 0; 1249 } 1250 1251 static unsigned long resize_hpt_rehash_hpte(struct kvm_resize_hpt *resize, 1252 unsigned long idx) 1253 { 1254 struct kvm *kvm = resize->kvm; 1255 struct kvm_hpt_info *old = &kvm->arch.hpt; 1256 struct kvm_hpt_info *new = &resize->hpt; 1257 unsigned long old_hash_mask = (1ULL << (old->order - 7)) - 1; 1258 unsigned long new_hash_mask = (1ULL << (new->order - 7)) - 1; 1259 __be64 *hptep, *new_hptep; 1260 unsigned long vpte, rpte, guest_rpte; 1261 int ret; 1262 struct revmap_entry *rev; 1263 unsigned long apsize, avpn, pteg, hash; 1264 unsigned long new_idx, new_pteg, replace_vpte; 1265 int pshift; 1266 1267 hptep = (__be64 *)(old->virt + (idx << 4)); 1268 1269 /* Guest is stopped, so new HPTEs can't be added or faulted 1270 * in, only unmapped or altered by host actions. So, it's 1271 * safe to check this before we take the HPTE lock */ 1272 vpte = be64_to_cpu(hptep[0]); 1273 if (!(vpte & HPTE_V_VALID) && !(vpte & HPTE_V_ABSENT)) 1274 return 0; /* nothing to do */ 1275 1276 while (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) 1277 cpu_relax(); 1278 1279 vpte = be64_to_cpu(hptep[0]); 1280 1281 ret = 0; 1282 if (!(vpte & HPTE_V_VALID) && !(vpte & HPTE_V_ABSENT)) 1283 /* Nothing to do */ 1284 goto out; 1285 1286 if (cpu_has_feature(CPU_FTR_ARCH_300)) { 1287 rpte = be64_to_cpu(hptep[1]); 1288 vpte = hpte_new_to_old_v(vpte, rpte); 1289 } 1290 1291 /* Unmap */ 1292 rev = &old->rev[idx]; 1293 guest_rpte = rev->guest_rpte; 1294 1295 ret = -EIO; 1296 apsize = kvmppc_actual_pgsz(vpte, guest_rpte); 1297 if (!apsize) 1298 goto out; 1299 1300 if (vpte & HPTE_V_VALID) { 1301 unsigned long gfn = hpte_rpn(guest_rpte, apsize); 1302 int srcu_idx = srcu_read_lock(&kvm->srcu); 1303 struct kvm_memory_slot *memslot = 1304 __gfn_to_memslot(kvm_memslots(kvm), gfn); 1305 1306 if (memslot) { 1307 unsigned long *rmapp; 1308 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 1309 1310 lock_rmap(rmapp); 1311 kvmppc_unmap_hpte(kvm, idx, memslot, rmapp, gfn); 1312 unlock_rmap(rmapp); 1313 } 1314 1315 srcu_read_unlock(&kvm->srcu, srcu_idx); 1316 } 1317 1318 /* Reload PTE after unmap */ 1319 vpte = be64_to_cpu(hptep[0]); 1320 BUG_ON(vpte & HPTE_V_VALID); 1321 BUG_ON(!(vpte & HPTE_V_ABSENT)); 1322 1323 ret = 0; 1324 if (!(vpte & HPTE_V_BOLTED)) 1325 goto out; 1326 1327 rpte = be64_to_cpu(hptep[1]); 1328 1329 if (cpu_has_feature(CPU_FTR_ARCH_300)) { 1330 vpte = hpte_new_to_old_v(vpte, rpte); 1331 rpte = hpte_new_to_old_r(rpte); 1332 } 1333 1334 pshift = kvmppc_hpte_base_page_shift(vpte, rpte); 1335 avpn = HPTE_V_AVPN_VAL(vpte) & ~(((1ul << pshift) - 1) >> 23); 1336 pteg = idx / HPTES_PER_GROUP; 1337 if (vpte & HPTE_V_SECONDARY) 1338 pteg = ~pteg; 1339 1340 if (!(vpte & HPTE_V_1TB_SEG)) { 1341 unsigned long offset, vsid; 1342 1343 /* We only have 28 - 23 bits of offset in avpn */ 1344 offset = (avpn & 0x1f) << 23; 1345 vsid = avpn >> 5; 1346 /* We can find more bits from the pteg value */ 1347 if (pshift < 23) 1348 offset |= ((vsid ^ pteg) & old_hash_mask) << pshift; 1349 1350 hash = vsid ^ (offset >> pshift); 1351 } else { 1352 unsigned long offset, vsid; 1353 1354 /* We only have 40 - 23 bits of seg_off in avpn */ 1355 offset = (avpn & 0x1ffff) << 23; 1356 vsid = avpn >> 17; 1357 if (pshift < 23) 1358 offset |= ((vsid ^ (vsid << 25) ^ pteg) & old_hash_mask) << pshift; 1359 1360 hash = vsid ^ (vsid << 25) ^ (offset >> pshift); 1361 } 1362 1363 new_pteg = hash & new_hash_mask; 1364 if (vpte & HPTE_V_SECONDARY) 1365 new_pteg = ~hash & new_hash_mask; 1366 1367 new_idx = new_pteg * HPTES_PER_GROUP + (idx % HPTES_PER_GROUP); 1368 new_hptep = (__be64 *)(new->virt + (new_idx << 4)); 1369 1370 replace_vpte = be64_to_cpu(new_hptep[0]); 1371 if (cpu_has_feature(CPU_FTR_ARCH_300)) { 1372 unsigned long replace_rpte = be64_to_cpu(new_hptep[1]); 1373 replace_vpte = hpte_new_to_old_v(replace_vpte, replace_rpte); 1374 } 1375 1376 if (replace_vpte & (HPTE_V_VALID | HPTE_V_ABSENT)) { 1377 BUG_ON(new->order >= old->order); 1378 1379 if (replace_vpte & HPTE_V_BOLTED) { 1380 if (vpte & HPTE_V_BOLTED) 1381 /* Bolted collision, nothing we can do */ 1382 ret = -ENOSPC; 1383 /* Discard the new HPTE */ 1384 goto out; 1385 } 1386 1387 /* Discard the previous HPTE */ 1388 } 1389 1390 if (cpu_has_feature(CPU_FTR_ARCH_300)) { 1391 rpte = hpte_old_to_new_r(vpte, rpte); 1392 vpte = hpte_old_to_new_v(vpte); 1393 } 1394 1395 new_hptep[1] = cpu_to_be64(rpte); 1396 new->rev[new_idx].guest_rpte = guest_rpte; 1397 /* No need for a barrier, since new HPT isn't active */ 1398 new_hptep[0] = cpu_to_be64(vpte); 1399 unlock_hpte(new_hptep, vpte); 1400 1401 out: 1402 unlock_hpte(hptep, vpte); 1403 return ret; 1404 } 1405 1406 static int resize_hpt_rehash(struct kvm_resize_hpt *resize) 1407 { 1408 struct kvm *kvm = resize->kvm; 1409 unsigned long i; 1410 int rc; 1411 1412 for (i = 0; i < kvmppc_hpt_npte(&kvm->arch.hpt); i++) { 1413 rc = resize_hpt_rehash_hpte(resize, i); 1414 if (rc != 0) 1415 return rc; 1416 } 1417 1418 return 0; 1419 } 1420 1421 static void resize_hpt_pivot(struct kvm_resize_hpt *resize) 1422 { 1423 struct kvm *kvm = resize->kvm; 1424 struct kvm_hpt_info hpt_tmp; 1425 1426 /* Exchange the pending tables in the resize structure with 1427 * the active tables */ 1428 1429 resize_hpt_debug(resize, "resize_hpt_pivot()\n"); 1430 1431 spin_lock(&kvm->mmu_lock); 1432 asm volatile("ptesync" : : : "memory"); 1433 1434 hpt_tmp = kvm->arch.hpt; 1435 kvmppc_set_hpt(kvm, &resize->hpt); 1436 resize->hpt = hpt_tmp; 1437 1438 spin_unlock(&kvm->mmu_lock); 1439 1440 synchronize_srcu_expedited(&kvm->srcu); 1441 1442 if (cpu_has_feature(CPU_FTR_ARCH_300)) 1443 kvmppc_setup_partition_table(kvm); 1444 1445 resize_hpt_debug(resize, "resize_hpt_pivot() done\n"); 1446 } 1447 1448 static void resize_hpt_release(struct kvm *kvm, struct kvm_resize_hpt *resize) 1449 { 1450 if (WARN_ON(!mutex_is_locked(&kvm->lock))) 1451 return; 1452 1453 if (!resize) 1454 return; 1455 1456 if (resize->error != -EBUSY) { 1457 if (resize->hpt.virt) 1458 kvmppc_free_hpt(&resize->hpt); 1459 kfree(resize); 1460 } 1461 1462 if (kvm->arch.resize_hpt == resize) 1463 kvm->arch.resize_hpt = NULL; 1464 } 1465 1466 static void resize_hpt_prepare_work(struct work_struct *work) 1467 { 1468 struct kvm_resize_hpt *resize = container_of(work, 1469 struct kvm_resize_hpt, 1470 work); 1471 struct kvm *kvm = resize->kvm; 1472 int err = 0; 1473 1474 if (WARN_ON(resize->error != -EBUSY)) 1475 return; 1476 1477 mutex_lock(&kvm->lock); 1478 1479 /* Request is still current? */ 1480 if (kvm->arch.resize_hpt == resize) { 1481 /* We may request large allocations here: 1482 * do not sleep with kvm->lock held for a while. 1483 */ 1484 mutex_unlock(&kvm->lock); 1485 1486 resize_hpt_debug(resize, "resize_hpt_prepare_work(): order = %d\n", 1487 resize->order); 1488 1489 err = resize_hpt_allocate(resize); 1490 1491 /* We have strict assumption about -EBUSY 1492 * when preparing for HPT resize. 1493 */ 1494 if (WARN_ON(err == -EBUSY)) 1495 err = -EINPROGRESS; 1496 1497 mutex_lock(&kvm->lock); 1498 /* It is possible that kvm->arch.resize_hpt != resize 1499 * after we grab kvm->lock again. 1500 */ 1501 } 1502 1503 resize->error = err; 1504 1505 if (kvm->arch.resize_hpt != resize) 1506 resize_hpt_release(kvm, resize); 1507 1508 mutex_unlock(&kvm->lock); 1509 } 1510 1511 long kvm_vm_ioctl_resize_hpt_prepare(struct kvm *kvm, 1512 struct kvm_ppc_resize_hpt *rhpt) 1513 { 1514 unsigned long flags = rhpt->flags; 1515 unsigned long shift = rhpt->shift; 1516 struct kvm_resize_hpt *resize; 1517 int ret; 1518 1519 if (flags != 0 || kvm_is_radix(kvm)) 1520 return -EINVAL; 1521 1522 if (shift && ((shift < 18) || (shift > 46))) 1523 return -EINVAL; 1524 1525 mutex_lock(&kvm->lock); 1526 1527 resize = kvm->arch.resize_hpt; 1528 1529 if (resize) { 1530 if (resize->order == shift) { 1531 /* Suitable resize in progress? */ 1532 ret = resize->error; 1533 if (ret == -EBUSY) 1534 ret = 100; /* estimated time in ms */ 1535 else if (ret) 1536 resize_hpt_release(kvm, resize); 1537 1538 goto out; 1539 } 1540 1541 /* not suitable, cancel it */ 1542 resize_hpt_release(kvm, resize); 1543 } 1544 1545 ret = 0; 1546 if (!shift) 1547 goto out; /* nothing to do */ 1548 1549 /* start new resize */ 1550 1551 resize = kzalloc(sizeof(*resize), GFP_KERNEL); 1552 if (!resize) { 1553 ret = -ENOMEM; 1554 goto out; 1555 } 1556 1557 resize->error = -EBUSY; 1558 resize->order = shift; 1559 resize->kvm = kvm; 1560 INIT_WORK(&resize->work, resize_hpt_prepare_work); 1561 kvm->arch.resize_hpt = resize; 1562 1563 schedule_work(&resize->work); 1564 1565 ret = 100; /* estimated time in ms */ 1566 1567 out: 1568 mutex_unlock(&kvm->lock); 1569 return ret; 1570 } 1571 1572 static void resize_hpt_boot_vcpu(void *opaque) 1573 { 1574 /* Nothing to do, just force a KVM exit */ 1575 } 1576 1577 long kvm_vm_ioctl_resize_hpt_commit(struct kvm *kvm, 1578 struct kvm_ppc_resize_hpt *rhpt) 1579 { 1580 unsigned long flags = rhpt->flags; 1581 unsigned long shift = rhpt->shift; 1582 struct kvm_resize_hpt *resize; 1583 long ret; 1584 1585 if (flags != 0 || kvm_is_radix(kvm)) 1586 return -EINVAL; 1587 1588 if (shift && ((shift < 18) || (shift > 46))) 1589 return -EINVAL; 1590 1591 mutex_lock(&kvm->lock); 1592 1593 resize = kvm->arch.resize_hpt; 1594 1595 /* This shouldn't be possible */ 1596 ret = -EIO; 1597 if (WARN_ON(!kvm->arch.mmu_ready)) 1598 goto out_no_hpt; 1599 1600 /* Stop VCPUs from running while we mess with the HPT */ 1601 kvm->arch.mmu_ready = 0; 1602 smp_mb(); 1603 1604 /* Boot all CPUs out of the guest so they re-read 1605 * mmu_ready */ 1606 on_each_cpu(resize_hpt_boot_vcpu, NULL, 1); 1607 1608 ret = -ENXIO; 1609 if (!resize || (resize->order != shift)) 1610 goto out; 1611 1612 ret = resize->error; 1613 if (ret) 1614 goto out; 1615 1616 ret = resize_hpt_rehash(resize); 1617 if (ret) 1618 goto out; 1619 1620 resize_hpt_pivot(resize); 1621 1622 out: 1623 /* Let VCPUs run again */ 1624 kvm->arch.mmu_ready = 1; 1625 smp_mb(); 1626 out_no_hpt: 1627 resize_hpt_release(kvm, resize); 1628 mutex_unlock(&kvm->lock); 1629 return ret; 1630 } 1631 1632 /* 1633 * Functions for reading and writing the hash table via reads and 1634 * writes on a file descriptor. 1635 * 1636 * Reads return the guest view of the hash table, which has to be 1637 * pieced together from the real hash table and the guest_rpte 1638 * values in the revmap array. 1639 * 1640 * On writes, each HPTE written is considered in turn, and if it 1641 * is valid, it is written to the HPT as if an H_ENTER with the 1642 * exact flag set was done. When the invalid count is non-zero 1643 * in the header written to the stream, the kernel will make 1644 * sure that that many HPTEs are invalid, and invalidate them 1645 * if not. 1646 */ 1647 1648 struct kvm_htab_ctx { 1649 unsigned long index; 1650 unsigned long flags; 1651 struct kvm *kvm; 1652 int first_pass; 1653 }; 1654 1655 #define HPTE_SIZE (2 * sizeof(unsigned long)) 1656 1657 /* 1658 * Returns 1 if this HPT entry has been modified or has pending 1659 * R/C bit changes. 1660 */ 1661 static int hpte_dirty(struct revmap_entry *revp, __be64 *hptp) 1662 { 1663 unsigned long rcbits_unset; 1664 1665 if (revp->guest_rpte & HPTE_GR_MODIFIED) 1666 return 1; 1667 1668 /* Also need to consider changes in reference and changed bits */ 1669 rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C); 1670 if ((be64_to_cpu(hptp[0]) & HPTE_V_VALID) && 1671 (be64_to_cpu(hptp[1]) & rcbits_unset)) 1672 return 1; 1673 1674 return 0; 1675 } 1676 1677 static long record_hpte(unsigned long flags, __be64 *hptp, 1678 unsigned long *hpte, struct revmap_entry *revp, 1679 int want_valid, int first_pass) 1680 { 1681 unsigned long v, r, hr; 1682 unsigned long rcbits_unset; 1683 int ok = 1; 1684 int valid, dirty; 1685 1686 /* Unmodified entries are uninteresting except on the first pass */ 1687 dirty = hpte_dirty(revp, hptp); 1688 if (!first_pass && !dirty) 1689 return 0; 1690 1691 valid = 0; 1692 if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)) { 1693 valid = 1; 1694 if ((flags & KVM_GET_HTAB_BOLTED_ONLY) && 1695 !(be64_to_cpu(hptp[0]) & HPTE_V_BOLTED)) 1696 valid = 0; 1697 } 1698 if (valid != want_valid) 1699 return 0; 1700 1701 v = r = 0; 1702 if (valid || dirty) { 1703 /* lock the HPTE so it's stable and read it */ 1704 preempt_disable(); 1705 while (!try_lock_hpte(hptp, HPTE_V_HVLOCK)) 1706 cpu_relax(); 1707 v = be64_to_cpu(hptp[0]); 1708 hr = be64_to_cpu(hptp[1]); 1709 if (cpu_has_feature(CPU_FTR_ARCH_300)) { 1710 v = hpte_new_to_old_v(v, hr); 1711 hr = hpte_new_to_old_r(hr); 1712 } 1713 1714 /* re-evaluate valid and dirty from synchronized HPTE value */ 1715 valid = !!(v & HPTE_V_VALID); 1716 dirty = !!(revp->guest_rpte & HPTE_GR_MODIFIED); 1717 1718 /* Harvest R and C into guest view if necessary */ 1719 rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C); 1720 if (valid && (rcbits_unset & hr)) { 1721 revp->guest_rpte |= (hr & 1722 (HPTE_R_R | HPTE_R_C)) | HPTE_GR_MODIFIED; 1723 dirty = 1; 1724 } 1725 1726 if (v & HPTE_V_ABSENT) { 1727 v &= ~HPTE_V_ABSENT; 1728 v |= HPTE_V_VALID; 1729 valid = 1; 1730 } 1731 if ((flags & KVM_GET_HTAB_BOLTED_ONLY) && !(v & HPTE_V_BOLTED)) 1732 valid = 0; 1733 1734 r = revp->guest_rpte; 1735 /* only clear modified if this is the right sort of entry */ 1736 if (valid == want_valid && dirty) { 1737 r &= ~HPTE_GR_MODIFIED; 1738 revp->guest_rpte = r; 1739 } 1740 unlock_hpte(hptp, be64_to_cpu(hptp[0])); 1741 preempt_enable(); 1742 if (!(valid == want_valid && (first_pass || dirty))) 1743 ok = 0; 1744 } 1745 hpte[0] = cpu_to_be64(v); 1746 hpte[1] = cpu_to_be64(r); 1747 return ok; 1748 } 1749 1750 static ssize_t kvm_htab_read(struct file *file, char __user *buf, 1751 size_t count, loff_t *ppos) 1752 { 1753 struct kvm_htab_ctx *ctx = file->private_data; 1754 struct kvm *kvm = ctx->kvm; 1755 struct kvm_get_htab_header hdr; 1756 __be64 *hptp; 1757 struct revmap_entry *revp; 1758 unsigned long i, nb, nw; 1759 unsigned long __user *lbuf; 1760 struct kvm_get_htab_header __user *hptr; 1761 unsigned long flags; 1762 int first_pass; 1763 unsigned long hpte[2]; 1764 1765 if (!access_ok(buf, count)) 1766 return -EFAULT; 1767 if (kvm_is_radix(kvm)) 1768 return 0; 1769 1770 first_pass = ctx->first_pass; 1771 flags = ctx->flags; 1772 1773 i = ctx->index; 1774 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE)); 1775 revp = kvm->arch.hpt.rev + i; 1776 lbuf = (unsigned long __user *)buf; 1777 1778 nb = 0; 1779 while (nb + sizeof(hdr) + HPTE_SIZE < count) { 1780 /* Initialize header */ 1781 hptr = (struct kvm_get_htab_header __user *)buf; 1782 hdr.n_valid = 0; 1783 hdr.n_invalid = 0; 1784 nw = nb; 1785 nb += sizeof(hdr); 1786 lbuf = (unsigned long __user *)(buf + sizeof(hdr)); 1787 1788 /* Skip uninteresting entries, i.e. clean on not-first pass */ 1789 if (!first_pass) { 1790 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) && 1791 !hpte_dirty(revp, hptp)) { 1792 ++i; 1793 hptp += 2; 1794 ++revp; 1795 } 1796 } 1797 hdr.index = i; 1798 1799 /* Grab a series of valid entries */ 1800 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) && 1801 hdr.n_valid < 0xffff && 1802 nb + HPTE_SIZE < count && 1803 record_hpte(flags, hptp, hpte, revp, 1, first_pass)) { 1804 /* valid entry, write it out */ 1805 ++hdr.n_valid; 1806 if (__put_user(hpte[0], lbuf) || 1807 __put_user(hpte[1], lbuf + 1)) 1808 return -EFAULT; 1809 nb += HPTE_SIZE; 1810 lbuf += 2; 1811 ++i; 1812 hptp += 2; 1813 ++revp; 1814 } 1815 /* Now skip invalid entries while we can */ 1816 while (i < kvmppc_hpt_npte(&kvm->arch.hpt) && 1817 hdr.n_invalid < 0xffff && 1818 record_hpte(flags, hptp, hpte, revp, 0, first_pass)) { 1819 /* found an invalid entry */ 1820 ++hdr.n_invalid; 1821 ++i; 1822 hptp += 2; 1823 ++revp; 1824 } 1825 1826 if (hdr.n_valid || hdr.n_invalid) { 1827 /* write back the header */ 1828 if (__copy_to_user(hptr, &hdr, sizeof(hdr))) 1829 return -EFAULT; 1830 nw = nb; 1831 buf = (char __user *)lbuf; 1832 } else { 1833 nb = nw; 1834 } 1835 1836 /* Check if we've wrapped around the hash table */ 1837 if (i >= kvmppc_hpt_npte(&kvm->arch.hpt)) { 1838 i = 0; 1839 ctx->first_pass = 0; 1840 break; 1841 } 1842 } 1843 1844 ctx->index = i; 1845 1846 return nb; 1847 } 1848 1849 static ssize_t kvm_htab_write(struct file *file, const char __user *buf, 1850 size_t count, loff_t *ppos) 1851 { 1852 struct kvm_htab_ctx *ctx = file->private_data; 1853 struct kvm *kvm = ctx->kvm; 1854 struct kvm_get_htab_header hdr; 1855 unsigned long i, j; 1856 unsigned long v, r; 1857 unsigned long __user *lbuf; 1858 __be64 *hptp; 1859 unsigned long tmp[2]; 1860 ssize_t nb; 1861 long int err, ret; 1862 int mmu_ready; 1863 int pshift; 1864 1865 if (!access_ok(buf, count)) 1866 return -EFAULT; 1867 if (kvm_is_radix(kvm)) 1868 return -EINVAL; 1869 1870 /* lock out vcpus from running while we're doing this */ 1871 mutex_lock(&kvm->lock); 1872 mmu_ready = kvm->arch.mmu_ready; 1873 if (mmu_ready) { 1874 kvm->arch.mmu_ready = 0; /* temporarily */ 1875 /* order mmu_ready vs. vcpus_running */ 1876 smp_mb(); 1877 if (atomic_read(&kvm->arch.vcpus_running)) { 1878 kvm->arch.mmu_ready = 1; 1879 mutex_unlock(&kvm->lock); 1880 return -EBUSY; 1881 } 1882 } 1883 1884 err = 0; 1885 for (nb = 0; nb + sizeof(hdr) <= count; ) { 1886 err = -EFAULT; 1887 if (__copy_from_user(&hdr, buf, sizeof(hdr))) 1888 break; 1889 1890 err = 0; 1891 if (nb + hdr.n_valid * HPTE_SIZE > count) 1892 break; 1893 1894 nb += sizeof(hdr); 1895 buf += sizeof(hdr); 1896 1897 err = -EINVAL; 1898 i = hdr.index; 1899 if (i >= kvmppc_hpt_npte(&kvm->arch.hpt) || 1900 i + hdr.n_valid + hdr.n_invalid > kvmppc_hpt_npte(&kvm->arch.hpt)) 1901 break; 1902 1903 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE)); 1904 lbuf = (unsigned long __user *)buf; 1905 for (j = 0; j < hdr.n_valid; ++j) { 1906 __be64 hpte_v; 1907 __be64 hpte_r; 1908 1909 err = -EFAULT; 1910 if (__get_user(hpte_v, lbuf) || 1911 __get_user(hpte_r, lbuf + 1)) 1912 goto out; 1913 v = be64_to_cpu(hpte_v); 1914 r = be64_to_cpu(hpte_r); 1915 err = -EINVAL; 1916 if (!(v & HPTE_V_VALID)) 1917 goto out; 1918 pshift = kvmppc_hpte_base_page_shift(v, r); 1919 if (pshift <= 0) 1920 goto out; 1921 lbuf += 2; 1922 nb += HPTE_SIZE; 1923 1924 if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)) 1925 kvmppc_do_h_remove(kvm, 0, i, 0, tmp); 1926 err = -EIO; 1927 ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, i, v, r, 1928 tmp); 1929 if (ret != H_SUCCESS) { 1930 pr_err("kvm_htab_write ret %ld i=%ld v=%lx " 1931 "r=%lx\n", ret, i, v, r); 1932 goto out; 1933 } 1934 if (!mmu_ready && is_vrma_hpte(v)) { 1935 unsigned long senc, lpcr; 1936 1937 senc = slb_pgsize_encoding(1ul << pshift); 1938 kvm->arch.vrma_slb_v = senc | SLB_VSID_B_1T | 1939 (VRMA_VSID << SLB_VSID_SHIFT_1T); 1940 if (!cpu_has_feature(CPU_FTR_ARCH_300)) { 1941 lpcr = senc << (LPCR_VRMASD_SH - 4); 1942 kvmppc_update_lpcr(kvm, lpcr, 1943 LPCR_VRMASD); 1944 } else { 1945 kvmppc_setup_partition_table(kvm); 1946 } 1947 mmu_ready = 1; 1948 } 1949 ++i; 1950 hptp += 2; 1951 } 1952 1953 for (j = 0; j < hdr.n_invalid; ++j) { 1954 if (be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)) 1955 kvmppc_do_h_remove(kvm, 0, i, 0, tmp); 1956 ++i; 1957 hptp += 2; 1958 } 1959 err = 0; 1960 } 1961 1962 out: 1963 /* Order HPTE updates vs. mmu_ready */ 1964 smp_wmb(); 1965 kvm->arch.mmu_ready = mmu_ready; 1966 mutex_unlock(&kvm->lock); 1967 1968 if (err) 1969 return err; 1970 return nb; 1971 } 1972 1973 static int kvm_htab_release(struct inode *inode, struct file *filp) 1974 { 1975 struct kvm_htab_ctx *ctx = filp->private_data; 1976 1977 filp->private_data = NULL; 1978 if (!(ctx->flags & KVM_GET_HTAB_WRITE)) 1979 atomic_dec(&ctx->kvm->arch.hpte_mod_interest); 1980 kvm_put_kvm(ctx->kvm); 1981 kfree(ctx); 1982 return 0; 1983 } 1984 1985 static const struct file_operations kvm_htab_fops = { 1986 .read = kvm_htab_read, 1987 .write = kvm_htab_write, 1988 .llseek = default_llseek, 1989 .release = kvm_htab_release, 1990 }; 1991 1992 int kvm_vm_ioctl_get_htab_fd(struct kvm *kvm, struct kvm_get_htab_fd *ghf) 1993 { 1994 int ret; 1995 struct kvm_htab_ctx *ctx; 1996 int rwflag; 1997 1998 /* reject flags we don't recognize */ 1999 if (ghf->flags & ~(KVM_GET_HTAB_BOLTED_ONLY | KVM_GET_HTAB_WRITE)) 2000 return -EINVAL; 2001 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); 2002 if (!ctx) 2003 return -ENOMEM; 2004 kvm_get_kvm(kvm); 2005 ctx->kvm = kvm; 2006 ctx->index = ghf->start_index; 2007 ctx->flags = ghf->flags; 2008 ctx->first_pass = 1; 2009 2010 rwflag = (ghf->flags & KVM_GET_HTAB_WRITE) ? O_WRONLY : O_RDONLY; 2011 ret = anon_inode_getfd("kvm-htab", &kvm_htab_fops, ctx, rwflag | O_CLOEXEC); 2012 if (ret < 0) { 2013 kfree(ctx); 2014 kvm_put_kvm(kvm); 2015 return ret; 2016 } 2017 2018 if (rwflag == O_RDONLY) { 2019 mutex_lock(&kvm->slots_lock); 2020 atomic_inc(&kvm->arch.hpte_mod_interest); 2021 /* make sure kvmppc_do_h_enter etc. see the increment */ 2022 synchronize_srcu_expedited(&kvm->srcu); 2023 mutex_unlock(&kvm->slots_lock); 2024 } 2025 2026 return ret; 2027 } 2028 2029 struct debugfs_htab_state { 2030 struct kvm *kvm; 2031 struct mutex mutex; 2032 unsigned long hpt_index; 2033 int chars_left; 2034 int buf_index; 2035 char buf[64]; 2036 }; 2037 2038 static int debugfs_htab_open(struct inode *inode, struct file *file) 2039 { 2040 struct kvm *kvm = inode->i_private; 2041 struct debugfs_htab_state *p; 2042 2043 p = kzalloc(sizeof(*p), GFP_KERNEL); 2044 if (!p) 2045 return -ENOMEM; 2046 2047 kvm_get_kvm(kvm); 2048 p->kvm = kvm; 2049 mutex_init(&p->mutex); 2050 file->private_data = p; 2051 2052 return nonseekable_open(inode, file); 2053 } 2054 2055 static int debugfs_htab_release(struct inode *inode, struct file *file) 2056 { 2057 struct debugfs_htab_state *p = file->private_data; 2058 2059 kvm_put_kvm(p->kvm); 2060 kfree(p); 2061 return 0; 2062 } 2063 2064 static ssize_t debugfs_htab_read(struct file *file, char __user *buf, 2065 size_t len, loff_t *ppos) 2066 { 2067 struct debugfs_htab_state *p = file->private_data; 2068 ssize_t ret, r; 2069 unsigned long i, n; 2070 unsigned long v, hr, gr; 2071 struct kvm *kvm; 2072 __be64 *hptp; 2073 2074 kvm = p->kvm; 2075 if (kvm_is_radix(kvm)) 2076 return 0; 2077 2078 ret = mutex_lock_interruptible(&p->mutex); 2079 if (ret) 2080 return ret; 2081 2082 if (p->chars_left) { 2083 n = p->chars_left; 2084 if (n > len) 2085 n = len; 2086 r = copy_to_user(buf, p->buf + p->buf_index, n); 2087 n -= r; 2088 p->chars_left -= n; 2089 p->buf_index += n; 2090 buf += n; 2091 len -= n; 2092 ret = n; 2093 if (r) { 2094 if (!n) 2095 ret = -EFAULT; 2096 goto out; 2097 } 2098 } 2099 2100 i = p->hpt_index; 2101 hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE)); 2102 for (; len != 0 && i < kvmppc_hpt_npte(&kvm->arch.hpt); 2103 ++i, hptp += 2) { 2104 if (!(be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT))) 2105 continue; 2106 2107 /* lock the HPTE so it's stable and read it */ 2108 preempt_disable(); 2109 while (!try_lock_hpte(hptp, HPTE_V_HVLOCK)) 2110 cpu_relax(); 2111 v = be64_to_cpu(hptp[0]) & ~HPTE_V_HVLOCK; 2112 hr = be64_to_cpu(hptp[1]); 2113 gr = kvm->arch.hpt.rev[i].guest_rpte; 2114 unlock_hpte(hptp, v); 2115 preempt_enable(); 2116 2117 if (!(v & (HPTE_V_VALID | HPTE_V_ABSENT))) 2118 continue; 2119 2120 n = scnprintf(p->buf, sizeof(p->buf), 2121 "%6lx %.16lx %.16lx %.16lx\n", 2122 i, v, hr, gr); 2123 p->chars_left = n; 2124 if (n > len) 2125 n = len; 2126 r = copy_to_user(buf, p->buf, n); 2127 n -= r; 2128 p->chars_left -= n; 2129 p->buf_index = n; 2130 buf += n; 2131 len -= n; 2132 ret += n; 2133 if (r) { 2134 if (!ret) 2135 ret = -EFAULT; 2136 goto out; 2137 } 2138 } 2139 p->hpt_index = i; 2140 2141 out: 2142 mutex_unlock(&p->mutex); 2143 return ret; 2144 } 2145 2146 static ssize_t debugfs_htab_write(struct file *file, const char __user *buf, 2147 size_t len, loff_t *ppos) 2148 { 2149 return -EACCES; 2150 } 2151 2152 static const struct file_operations debugfs_htab_fops = { 2153 .owner = THIS_MODULE, 2154 .open = debugfs_htab_open, 2155 .release = debugfs_htab_release, 2156 .read = debugfs_htab_read, 2157 .write = debugfs_htab_write, 2158 .llseek = generic_file_llseek, 2159 }; 2160 2161 void kvmppc_mmu_debugfs_init(struct kvm *kvm) 2162 { 2163 kvm->arch.htab_dentry = debugfs_create_file("htab", 0400, 2164 kvm->arch.debugfs_dir, kvm, 2165 &debugfs_htab_fops); 2166 } 2167 2168 void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu) 2169 { 2170 struct kvmppc_mmu *mmu = &vcpu->arch.mmu; 2171 2172 vcpu->arch.slb_nr = 32; /* POWER7/POWER8 */ 2173 2174 mmu->xlate = kvmppc_mmu_book3s_64_hv_xlate; 2175 mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr; 2176 2177 vcpu->arch.hflags |= BOOK3S_HFLAG_SLB; 2178 } 2179