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 * Copyright 2011 David Gibson, IBM Corporation <dwg@au1.ibm.com> 17 * Copyright 2016 Alexey Kardashevskiy, IBM Corporation <aik@au1.ibm.com> 18 */ 19 20 #include <linux/types.h> 21 #include <linux/string.h> 22 #include <linux/kvm.h> 23 #include <linux/kvm_host.h> 24 #include <linux/highmem.h> 25 #include <linux/gfp.h> 26 #include <linux/slab.h> 27 #include <linux/sched/signal.h> 28 #include <linux/hugetlb.h> 29 #include <linux/list.h> 30 #include <linux/anon_inodes.h> 31 #include <linux/iommu.h> 32 #include <linux/file.h> 33 34 #include <asm/kvm_ppc.h> 35 #include <asm/kvm_book3s.h> 36 #include <asm/book3s/64/mmu-hash.h> 37 #include <asm/hvcall.h> 38 #include <asm/synch.h> 39 #include <asm/ppc-opcode.h> 40 #include <asm/kvm_host.h> 41 #include <asm/udbg.h> 42 #include <asm/iommu.h> 43 #include <asm/tce.h> 44 #include <asm/mmu_context.h> 45 46 static unsigned long kvmppc_tce_pages(unsigned long iommu_pages) 47 { 48 return ALIGN(iommu_pages * sizeof(u64), PAGE_SIZE) / PAGE_SIZE; 49 } 50 51 static unsigned long kvmppc_stt_pages(unsigned long tce_pages) 52 { 53 unsigned long stt_bytes = sizeof(struct kvmppc_spapr_tce_table) + 54 (tce_pages * sizeof(struct page *)); 55 56 return tce_pages + ALIGN(stt_bytes, PAGE_SIZE) / PAGE_SIZE; 57 } 58 59 static long kvmppc_account_memlimit(unsigned long stt_pages, bool inc) 60 { 61 long ret = 0; 62 63 if (!current || !current->mm) 64 return ret; /* process exited */ 65 66 down_write(¤t->mm->mmap_sem); 67 68 if (inc) { 69 unsigned long locked, lock_limit; 70 71 locked = current->mm->locked_vm + stt_pages; 72 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 73 if (locked > lock_limit && !capable(CAP_IPC_LOCK)) 74 ret = -ENOMEM; 75 else 76 current->mm->locked_vm += stt_pages; 77 } else { 78 if (WARN_ON_ONCE(stt_pages > current->mm->locked_vm)) 79 stt_pages = current->mm->locked_vm; 80 81 current->mm->locked_vm -= stt_pages; 82 } 83 84 pr_debug("[%d] RLIMIT_MEMLOCK KVM %c%ld %ld/%ld%s\n", current->pid, 85 inc ? '+' : '-', 86 stt_pages << PAGE_SHIFT, 87 current->mm->locked_vm << PAGE_SHIFT, 88 rlimit(RLIMIT_MEMLOCK), 89 ret ? " - exceeded" : ""); 90 91 up_write(¤t->mm->mmap_sem); 92 93 return ret; 94 } 95 96 static void kvm_spapr_tce_iommu_table_free(struct rcu_head *head) 97 { 98 struct kvmppc_spapr_tce_iommu_table *stit = container_of(head, 99 struct kvmppc_spapr_tce_iommu_table, rcu); 100 101 iommu_tce_table_put(stit->tbl); 102 103 kfree(stit); 104 } 105 106 static void kvm_spapr_tce_liobn_put(struct kref *kref) 107 { 108 struct kvmppc_spapr_tce_iommu_table *stit = container_of(kref, 109 struct kvmppc_spapr_tce_iommu_table, kref); 110 111 list_del_rcu(&stit->next); 112 113 call_rcu(&stit->rcu, kvm_spapr_tce_iommu_table_free); 114 } 115 116 extern void kvm_spapr_tce_release_iommu_group(struct kvm *kvm, 117 struct iommu_group *grp) 118 { 119 int i; 120 struct kvmppc_spapr_tce_table *stt; 121 struct kvmppc_spapr_tce_iommu_table *stit, *tmp; 122 struct iommu_table_group *table_group = NULL; 123 124 list_for_each_entry_rcu(stt, &kvm->arch.spapr_tce_tables, list) { 125 126 table_group = iommu_group_get_iommudata(grp); 127 if (WARN_ON(!table_group)) 128 continue; 129 130 list_for_each_entry_safe(stit, tmp, &stt->iommu_tables, next) { 131 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 132 if (table_group->tables[i] != stit->tbl) 133 continue; 134 135 kref_put(&stit->kref, kvm_spapr_tce_liobn_put); 136 } 137 } 138 } 139 } 140 141 extern long kvm_spapr_tce_attach_iommu_group(struct kvm *kvm, int tablefd, 142 struct iommu_group *grp) 143 { 144 struct kvmppc_spapr_tce_table *stt = NULL; 145 bool found = false; 146 struct iommu_table *tbl = NULL; 147 struct iommu_table_group *table_group; 148 long i; 149 struct kvmppc_spapr_tce_iommu_table *stit; 150 struct fd f; 151 152 f = fdget(tablefd); 153 if (!f.file) 154 return -EBADF; 155 156 list_for_each_entry_rcu(stt, &kvm->arch.spapr_tce_tables, list) { 157 if (stt == f.file->private_data) { 158 found = true; 159 break; 160 } 161 } 162 163 fdput(f); 164 165 if (!found) 166 return -EINVAL; 167 168 table_group = iommu_group_get_iommudata(grp); 169 if (WARN_ON(!table_group)) 170 return -EFAULT; 171 172 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 173 struct iommu_table *tbltmp = table_group->tables[i]; 174 175 if (!tbltmp) 176 continue; 177 /* Make sure hardware table parameters are compatible */ 178 if ((tbltmp->it_page_shift <= stt->page_shift) && 179 (tbltmp->it_offset << tbltmp->it_page_shift == 180 stt->offset << stt->page_shift) && 181 (tbltmp->it_size << tbltmp->it_page_shift >= 182 stt->size << stt->page_shift)) { 183 /* 184 * Reference the table to avoid races with 185 * add/remove DMA windows. 186 */ 187 tbl = iommu_tce_table_get(tbltmp); 188 break; 189 } 190 } 191 if (!tbl) 192 return -EINVAL; 193 194 list_for_each_entry_rcu(stit, &stt->iommu_tables, next) { 195 if (tbl != stit->tbl) 196 continue; 197 198 if (!kref_get_unless_zero(&stit->kref)) { 199 /* stit is being destroyed */ 200 iommu_tce_table_put(tbl); 201 return -ENOTTY; 202 } 203 /* 204 * The table is already known to this KVM, we just increased 205 * its KVM reference counter and can return. 206 */ 207 return 0; 208 } 209 210 stit = kzalloc(sizeof(*stit), GFP_KERNEL); 211 if (!stit) { 212 iommu_tce_table_put(tbl); 213 return -ENOMEM; 214 } 215 216 stit->tbl = tbl; 217 kref_init(&stit->kref); 218 219 list_add_rcu(&stit->next, &stt->iommu_tables); 220 221 return 0; 222 } 223 224 static void release_spapr_tce_table(struct rcu_head *head) 225 { 226 struct kvmppc_spapr_tce_table *stt = container_of(head, 227 struct kvmppc_spapr_tce_table, rcu); 228 unsigned long i, npages = kvmppc_tce_pages(stt->size); 229 230 for (i = 0; i < npages; i++) 231 __free_page(stt->pages[i]); 232 233 kfree(stt); 234 } 235 236 static vm_fault_t kvm_spapr_tce_fault(struct vm_fault *vmf) 237 { 238 struct kvmppc_spapr_tce_table *stt = vmf->vma->vm_file->private_data; 239 struct page *page; 240 241 if (vmf->pgoff >= kvmppc_tce_pages(stt->size)) 242 return VM_FAULT_SIGBUS; 243 244 page = stt->pages[vmf->pgoff]; 245 get_page(page); 246 vmf->page = page; 247 return 0; 248 } 249 250 static const struct vm_operations_struct kvm_spapr_tce_vm_ops = { 251 .fault = kvm_spapr_tce_fault, 252 }; 253 254 static int kvm_spapr_tce_mmap(struct file *file, struct vm_area_struct *vma) 255 { 256 vma->vm_ops = &kvm_spapr_tce_vm_ops; 257 return 0; 258 } 259 260 static int kvm_spapr_tce_release(struct inode *inode, struct file *filp) 261 { 262 struct kvmppc_spapr_tce_table *stt = filp->private_data; 263 struct kvmppc_spapr_tce_iommu_table *stit, *tmp; 264 struct kvm *kvm = stt->kvm; 265 266 mutex_lock(&kvm->lock); 267 list_del_rcu(&stt->list); 268 mutex_unlock(&kvm->lock); 269 270 list_for_each_entry_safe(stit, tmp, &stt->iommu_tables, next) { 271 WARN_ON(!kref_read(&stit->kref)); 272 while (1) { 273 if (kref_put(&stit->kref, kvm_spapr_tce_liobn_put)) 274 break; 275 } 276 } 277 278 kvm_put_kvm(stt->kvm); 279 280 kvmppc_account_memlimit( 281 kvmppc_stt_pages(kvmppc_tce_pages(stt->size)), false); 282 call_rcu(&stt->rcu, release_spapr_tce_table); 283 284 return 0; 285 } 286 287 static const struct file_operations kvm_spapr_tce_fops = { 288 .mmap = kvm_spapr_tce_mmap, 289 .release = kvm_spapr_tce_release, 290 }; 291 292 long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, 293 struct kvm_create_spapr_tce_64 *args) 294 { 295 struct kvmppc_spapr_tce_table *stt = NULL; 296 struct kvmppc_spapr_tce_table *siter; 297 unsigned long npages, size = args->size; 298 int ret = -ENOMEM; 299 int i; 300 301 if (!args->size || args->page_shift < 12 || args->page_shift > 34 || 302 (args->offset + args->size > (ULLONG_MAX >> args->page_shift))) 303 return -EINVAL; 304 305 npages = kvmppc_tce_pages(size); 306 ret = kvmppc_account_memlimit(kvmppc_stt_pages(npages), true); 307 if (ret) 308 return ret; 309 310 ret = -ENOMEM; 311 stt = kzalloc(sizeof(*stt) + npages * sizeof(struct page *), 312 GFP_KERNEL); 313 if (!stt) 314 goto fail_acct; 315 316 stt->liobn = args->liobn; 317 stt->page_shift = args->page_shift; 318 stt->offset = args->offset; 319 stt->size = size; 320 stt->kvm = kvm; 321 INIT_LIST_HEAD_RCU(&stt->iommu_tables); 322 323 for (i = 0; i < npages; i++) { 324 stt->pages[i] = alloc_page(GFP_KERNEL | __GFP_ZERO); 325 if (!stt->pages[i]) 326 goto fail; 327 } 328 329 mutex_lock(&kvm->lock); 330 331 /* Check this LIOBN hasn't been previously allocated */ 332 ret = 0; 333 list_for_each_entry(siter, &kvm->arch.spapr_tce_tables, list) { 334 if (siter->liobn == args->liobn) { 335 ret = -EBUSY; 336 break; 337 } 338 } 339 340 kvm_get_kvm(kvm); 341 if (!ret) 342 ret = anon_inode_getfd("kvm-spapr-tce", &kvm_spapr_tce_fops, 343 stt, O_RDWR | O_CLOEXEC); 344 345 if (ret >= 0) 346 list_add_rcu(&stt->list, &kvm->arch.spapr_tce_tables); 347 else 348 kvm_put_kvm(kvm); 349 350 mutex_unlock(&kvm->lock); 351 352 if (ret >= 0) 353 return ret; 354 355 fail: 356 for (i = 0; i < npages; i++) 357 if (stt->pages[i]) 358 __free_page(stt->pages[i]); 359 360 kfree(stt); 361 fail_acct: 362 kvmppc_account_memlimit(kvmppc_stt_pages(npages), false); 363 return ret; 364 } 365 366 static long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, 367 unsigned long tce) 368 { 369 unsigned long gpa = tce & ~(TCE_PCI_READ | TCE_PCI_WRITE); 370 enum dma_data_direction dir = iommu_tce_direction(tce); 371 struct kvmppc_spapr_tce_iommu_table *stit; 372 unsigned long ua = 0; 373 374 /* Allow userspace to poison TCE table */ 375 if (dir == DMA_NONE) 376 return H_SUCCESS; 377 378 if (iommu_tce_check_gpa(stt->page_shift, gpa)) 379 return H_TOO_HARD; 380 381 if (kvmppc_tce_to_ua(stt->kvm, tce, &ua, NULL)) 382 return H_TOO_HARD; 383 384 list_for_each_entry_rcu(stit, &stt->iommu_tables, next) { 385 unsigned long hpa = 0; 386 struct mm_iommu_table_group_mem_t *mem; 387 long shift = stit->tbl->it_page_shift; 388 389 mem = mm_iommu_lookup(stt->kvm->mm, ua, 1ULL << shift); 390 if (!mem) 391 return H_TOO_HARD; 392 393 if (mm_iommu_ua_to_hpa(mem, ua, shift, &hpa)) 394 return H_TOO_HARD; 395 } 396 397 return H_SUCCESS; 398 } 399 400 static void kvmppc_clear_tce(struct mm_struct *mm, struct iommu_table *tbl, 401 unsigned long entry) 402 { 403 unsigned long hpa = 0; 404 enum dma_data_direction dir = DMA_NONE; 405 406 iommu_tce_xchg(mm, tbl, entry, &hpa, &dir); 407 } 408 409 static long kvmppc_tce_iommu_mapped_dec(struct kvm *kvm, 410 struct iommu_table *tbl, unsigned long entry) 411 { 412 struct mm_iommu_table_group_mem_t *mem = NULL; 413 const unsigned long pgsize = 1ULL << tbl->it_page_shift; 414 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl, entry); 415 416 if (!pua) 417 return H_SUCCESS; 418 419 mem = mm_iommu_lookup(kvm->mm, be64_to_cpu(*pua), pgsize); 420 if (!mem) 421 return H_TOO_HARD; 422 423 mm_iommu_mapped_dec(mem); 424 425 *pua = cpu_to_be64(0); 426 427 return H_SUCCESS; 428 } 429 430 static long kvmppc_tce_iommu_do_unmap(struct kvm *kvm, 431 struct iommu_table *tbl, unsigned long entry) 432 { 433 enum dma_data_direction dir = DMA_NONE; 434 unsigned long hpa = 0; 435 long ret; 436 437 if (WARN_ON_ONCE(iommu_tce_xchg(kvm->mm, tbl, entry, &hpa, &dir))) 438 return H_TOO_HARD; 439 440 if (dir == DMA_NONE) 441 return H_SUCCESS; 442 443 ret = kvmppc_tce_iommu_mapped_dec(kvm, tbl, entry); 444 if (ret != H_SUCCESS) 445 iommu_tce_xchg(kvm->mm, tbl, entry, &hpa, &dir); 446 447 return ret; 448 } 449 450 static long kvmppc_tce_iommu_unmap(struct kvm *kvm, 451 struct kvmppc_spapr_tce_table *stt, struct iommu_table *tbl, 452 unsigned long entry) 453 { 454 unsigned long i, ret = H_SUCCESS; 455 unsigned long subpages = 1ULL << (stt->page_shift - tbl->it_page_shift); 456 unsigned long io_entry = entry * subpages; 457 458 for (i = 0; i < subpages; ++i) { 459 ret = kvmppc_tce_iommu_do_unmap(kvm, tbl, io_entry + i); 460 if (ret != H_SUCCESS) 461 break; 462 } 463 464 return ret; 465 } 466 467 long kvmppc_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl, 468 unsigned long entry, unsigned long ua, 469 enum dma_data_direction dir) 470 { 471 long ret; 472 unsigned long hpa; 473 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry); 474 struct mm_iommu_table_group_mem_t *mem; 475 476 if (!pua) 477 /* it_userspace allocation might be delayed */ 478 return H_TOO_HARD; 479 480 mem = mm_iommu_lookup(kvm->mm, ua, 1ULL << tbl->it_page_shift); 481 if (!mem) 482 /* This only handles v2 IOMMU type, v1 is handled via ioctl() */ 483 return H_TOO_HARD; 484 485 if (WARN_ON_ONCE(mm_iommu_ua_to_hpa(mem, ua, tbl->it_page_shift, &hpa))) 486 return H_TOO_HARD; 487 488 if (mm_iommu_mapped_inc(mem)) 489 return H_TOO_HARD; 490 491 ret = iommu_tce_xchg(kvm->mm, tbl, entry, &hpa, &dir); 492 if (WARN_ON_ONCE(ret)) { 493 mm_iommu_mapped_dec(mem); 494 return H_TOO_HARD; 495 } 496 497 if (dir != DMA_NONE) 498 kvmppc_tce_iommu_mapped_dec(kvm, tbl, entry); 499 500 *pua = cpu_to_be64(ua); 501 502 return 0; 503 } 504 505 static long kvmppc_tce_iommu_map(struct kvm *kvm, 506 struct kvmppc_spapr_tce_table *stt, struct iommu_table *tbl, 507 unsigned long entry, unsigned long ua, 508 enum dma_data_direction dir) 509 { 510 unsigned long i, pgoff, ret = H_SUCCESS; 511 unsigned long subpages = 1ULL << (stt->page_shift - tbl->it_page_shift); 512 unsigned long io_entry = entry * subpages; 513 514 for (i = 0, pgoff = 0; i < subpages; 515 ++i, pgoff += IOMMU_PAGE_SIZE(tbl)) { 516 517 ret = kvmppc_tce_iommu_do_map(kvm, tbl, 518 io_entry + i, ua + pgoff, dir); 519 if (ret != H_SUCCESS) 520 break; 521 } 522 523 return ret; 524 } 525 526 long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, 527 unsigned long ioba, unsigned long tce) 528 { 529 struct kvmppc_spapr_tce_table *stt; 530 long ret, idx; 531 struct kvmppc_spapr_tce_iommu_table *stit; 532 unsigned long entry, ua = 0; 533 enum dma_data_direction dir; 534 535 /* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */ 536 /* liobn, ioba, tce); */ 537 538 stt = kvmppc_find_table(vcpu->kvm, liobn); 539 if (!stt) 540 return H_TOO_HARD; 541 542 ret = kvmppc_ioba_validate(stt, ioba, 1); 543 if (ret != H_SUCCESS) 544 return ret; 545 546 ret = kvmppc_tce_validate(stt, tce); 547 if (ret != H_SUCCESS) 548 return ret; 549 550 dir = iommu_tce_direction(tce); 551 552 idx = srcu_read_lock(&vcpu->kvm->srcu); 553 554 if ((dir != DMA_NONE) && kvmppc_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) { 555 ret = H_PARAMETER; 556 goto unlock_exit; 557 } 558 559 entry = ioba >> stt->page_shift; 560 561 list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { 562 if (dir == DMA_NONE) 563 ret = kvmppc_tce_iommu_unmap(vcpu->kvm, stt, 564 stit->tbl, entry); 565 else 566 ret = kvmppc_tce_iommu_map(vcpu->kvm, stt, stit->tbl, 567 entry, ua, dir); 568 569 if (ret != H_SUCCESS) { 570 kvmppc_clear_tce(vcpu->kvm->mm, stit->tbl, entry); 571 goto unlock_exit; 572 } 573 } 574 575 kvmppc_tce_put(stt, entry, tce); 576 577 unlock_exit: 578 srcu_read_unlock(&vcpu->kvm->srcu, idx); 579 580 return ret; 581 } 582 EXPORT_SYMBOL_GPL(kvmppc_h_put_tce); 583 584 long kvmppc_h_put_tce_indirect(struct kvm_vcpu *vcpu, 585 unsigned long liobn, unsigned long ioba, 586 unsigned long tce_list, unsigned long npages) 587 { 588 struct kvmppc_spapr_tce_table *stt; 589 long i, ret = H_SUCCESS, idx; 590 unsigned long entry, ua = 0; 591 u64 __user *tces; 592 u64 tce; 593 struct kvmppc_spapr_tce_iommu_table *stit; 594 595 stt = kvmppc_find_table(vcpu->kvm, liobn); 596 if (!stt) 597 return H_TOO_HARD; 598 599 entry = ioba >> stt->page_shift; 600 /* 601 * SPAPR spec says that the maximum size of the list is 512 TCEs 602 * so the whole table fits in 4K page 603 */ 604 if (npages > 512) 605 return H_PARAMETER; 606 607 if (tce_list & (SZ_4K - 1)) 608 return H_PARAMETER; 609 610 ret = kvmppc_ioba_validate(stt, ioba, npages); 611 if (ret != H_SUCCESS) 612 return ret; 613 614 idx = srcu_read_lock(&vcpu->kvm->srcu); 615 if (kvmppc_tce_to_ua(vcpu->kvm, tce_list, &ua, NULL)) { 616 ret = H_TOO_HARD; 617 goto unlock_exit; 618 } 619 tces = (u64 __user *) ua; 620 621 for (i = 0; i < npages; ++i) { 622 if (get_user(tce, tces + i)) { 623 ret = H_TOO_HARD; 624 goto unlock_exit; 625 } 626 tce = be64_to_cpu(tce); 627 628 ret = kvmppc_tce_validate(stt, tce); 629 if (ret != H_SUCCESS) 630 goto unlock_exit; 631 } 632 633 for (i = 0; i < npages; ++i) { 634 /* 635 * This looks unsafe, because we validate, then regrab 636 * the TCE from userspace which could have been changed by 637 * another thread. 638 * 639 * But it actually is safe, because the relevant checks will be 640 * re-executed in the following code. If userspace tries to 641 * change this dodgily it will result in a messier failure mode 642 * but won't threaten the host. 643 */ 644 if (get_user(tce, tces + i)) { 645 ret = H_TOO_HARD; 646 goto unlock_exit; 647 } 648 tce = be64_to_cpu(tce); 649 650 if (kvmppc_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) 651 return H_PARAMETER; 652 653 list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { 654 ret = kvmppc_tce_iommu_map(vcpu->kvm, stt, 655 stit->tbl, entry + i, ua, 656 iommu_tce_direction(tce)); 657 658 if (ret != H_SUCCESS) { 659 kvmppc_clear_tce(vcpu->kvm->mm, stit->tbl, 660 entry); 661 goto unlock_exit; 662 } 663 } 664 665 kvmppc_tce_put(stt, entry + i, tce); 666 } 667 668 unlock_exit: 669 srcu_read_unlock(&vcpu->kvm->srcu, idx); 670 671 return ret; 672 } 673 EXPORT_SYMBOL_GPL(kvmppc_h_put_tce_indirect); 674 675 long kvmppc_h_stuff_tce(struct kvm_vcpu *vcpu, 676 unsigned long liobn, unsigned long ioba, 677 unsigned long tce_value, unsigned long npages) 678 { 679 struct kvmppc_spapr_tce_table *stt; 680 long i, ret; 681 struct kvmppc_spapr_tce_iommu_table *stit; 682 683 stt = kvmppc_find_table(vcpu->kvm, liobn); 684 if (!stt) 685 return H_TOO_HARD; 686 687 ret = kvmppc_ioba_validate(stt, ioba, npages); 688 if (ret != H_SUCCESS) 689 return ret; 690 691 /* Check permission bits only to allow userspace poison TCE for debug */ 692 if (tce_value & (TCE_PCI_WRITE | TCE_PCI_READ)) 693 return H_PARAMETER; 694 695 list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { 696 unsigned long entry = ioba >> stt->page_shift; 697 698 for (i = 0; i < npages; ++i) { 699 ret = kvmppc_tce_iommu_unmap(vcpu->kvm, stt, 700 stit->tbl, entry + i); 701 702 if (ret == H_SUCCESS) 703 continue; 704 705 if (ret == H_TOO_HARD) 706 return ret; 707 708 WARN_ON_ONCE(1); 709 kvmppc_clear_tce(vcpu->kvm->mm, stit->tbl, entry); 710 } 711 } 712 713 for (i = 0; i < npages; ++i, ioba += (1ULL << stt->page_shift)) 714 kvmppc_tce_put(stt, ioba >> stt->page_shift, tce_value); 715 716 return H_SUCCESS; 717 } 718 EXPORT_SYMBOL_GPL(kvmppc_h_stuff_tce); 719