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(¤t->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(¤t->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 } 2108