1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * VFIO: IOMMU DMA mapping support for TCE on POWER 4 * 5 * Copyright (C) 2013 IBM Corp. All rights reserved. 6 * Author: Alexey Kardashevskiy <aik@ozlabs.ru> 7 * 8 * Derived from original vfio_iommu_type1.c: 9 * Copyright (C) 2012 Red Hat, Inc. All rights reserved. 10 * Author: Alex Williamson <alex.williamson@redhat.com> 11 */ 12 13 #include <linux/module.h> 14 #include <linux/pci.h> 15 #include <linux/slab.h> 16 #include <linux/uaccess.h> 17 #include <linux/err.h> 18 #include <linux/vfio.h> 19 #include <linux/vmalloc.h> 20 #include <linux/sched/mm.h> 21 #include <linux/sched/signal.h> 22 #include <linux/mm.h> 23 24 #include <asm/iommu.h> 25 #include <asm/tce.h> 26 #include <asm/mmu_context.h> 27 28 #define DRIVER_VERSION "0.1" 29 #define DRIVER_AUTHOR "aik@ozlabs.ru" 30 #define DRIVER_DESC "VFIO IOMMU SPAPR TCE" 31 32 static void tce_iommu_detach_group(void *iommu_data, 33 struct iommu_group *iommu_group); 34 35 /* 36 * VFIO IOMMU fd for SPAPR_TCE IOMMU implementation 37 * 38 * This code handles mapping and unmapping of user data buffers 39 * into DMA'ble space using the IOMMU 40 */ 41 42 struct tce_iommu_group { 43 struct list_head next; 44 struct iommu_group *grp; 45 }; 46 47 /* 48 * A container needs to remember which preregistered region it has 49 * referenced to do proper cleanup at the userspace process exit. 50 */ 51 struct tce_iommu_prereg { 52 struct list_head next; 53 struct mm_iommu_table_group_mem_t *mem; 54 }; 55 56 /* 57 * The container descriptor supports only a single group per container. 58 * Required by the API as the container is not supplied with the IOMMU group 59 * at the moment of initialization. 60 */ 61 struct tce_container { 62 struct mutex lock; 63 bool enabled; 64 bool v2; 65 bool def_window_pending; 66 unsigned long locked_pages; 67 struct mm_struct *mm; 68 struct iommu_table *tables[IOMMU_TABLE_GROUP_MAX_TABLES]; 69 struct list_head group_list; 70 struct list_head prereg_list; 71 }; 72 73 static long tce_iommu_mm_set(struct tce_container *container) 74 { 75 if (container->mm) { 76 if (container->mm == current->mm) 77 return 0; 78 return -EPERM; 79 } 80 BUG_ON(!current->mm); 81 container->mm = current->mm; 82 atomic_inc(&container->mm->mm_count); 83 84 return 0; 85 } 86 87 static long tce_iommu_prereg_free(struct tce_container *container, 88 struct tce_iommu_prereg *tcemem) 89 { 90 long ret; 91 92 ret = mm_iommu_put(container->mm, tcemem->mem); 93 if (ret) 94 return ret; 95 96 list_del(&tcemem->next); 97 kfree(tcemem); 98 99 return 0; 100 } 101 102 static long tce_iommu_unregister_pages(struct tce_container *container, 103 __u64 vaddr, __u64 size) 104 { 105 struct mm_iommu_table_group_mem_t *mem; 106 struct tce_iommu_prereg *tcemem; 107 bool found = false; 108 long ret; 109 110 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK)) 111 return -EINVAL; 112 113 mem = mm_iommu_get(container->mm, vaddr, size >> PAGE_SHIFT); 114 if (!mem) 115 return -ENOENT; 116 117 list_for_each_entry(tcemem, &container->prereg_list, next) { 118 if (tcemem->mem == mem) { 119 found = true; 120 break; 121 } 122 } 123 124 if (!found) 125 ret = -ENOENT; 126 else 127 ret = tce_iommu_prereg_free(container, tcemem); 128 129 mm_iommu_put(container->mm, mem); 130 131 return ret; 132 } 133 134 static long tce_iommu_register_pages(struct tce_container *container, 135 __u64 vaddr, __u64 size) 136 { 137 long ret = 0; 138 struct mm_iommu_table_group_mem_t *mem = NULL; 139 struct tce_iommu_prereg *tcemem; 140 unsigned long entries = size >> PAGE_SHIFT; 141 142 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK) || 143 ((vaddr + size) < vaddr)) 144 return -EINVAL; 145 146 mem = mm_iommu_get(container->mm, vaddr, entries); 147 if (mem) { 148 list_for_each_entry(tcemem, &container->prereg_list, next) { 149 if (tcemem->mem == mem) { 150 ret = -EBUSY; 151 goto put_exit; 152 } 153 } 154 } else { 155 ret = mm_iommu_new(container->mm, vaddr, entries, &mem); 156 if (ret) 157 return ret; 158 } 159 160 tcemem = kzalloc(sizeof(*tcemem), GFP_KERNEL); 161 if (!tcemem) { 162 ret = -ENOMEM; 163 goto put_exit; 164 } 165 166 tcemem->mem = mem; 167 list_add(&tcemem->next, &container->prereg_list); 168 169 container->enabled = true; 170 171 return 0; 172 173 put_exit: 174 mm_iommu_put(container->mm, mem); 175 return ret; 176 } 177 178 static bool tce_page_is_contained(struct mm_struct *mm, unsigned long hpa, 179 unsigned int page_shift) 180 { 181 struct page *page; 182 unsigned long size = 0; 183 184 if (mm_iommu_is_devmem(mm, hpa, page_shift, &size)) 185 return size == (1UL << page_shift); 186 187 page = pfn_to_page(hpa >> PAGE_SHIFT); 188 /* 189 * Check that the TCE table granularity is not bigger than the size of 190 * a page we just found. Otherwise the hardware can get access to 191 * a bigger memory chunk that it should. 192 */ 193 return (PAGE_SHIFT + compound_order(compound_head(page))) >= page_shift; 194 } 195 196 static inline bool tce_groups_attached(struct tce_container *container) 197 { 198 return !list_empty(&container->group_list); 199 } 200 201 static long tce_iommu_find_table(struct tce_container *container, 202 phys_addr_t ioba, struct iommu_table **ptbl) 203 { 204 long i; 205 206 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 207 struct iommu_table *tbl = container->tables[i]; 208 209 if (tbl) { 210 unsigned long entry = ioba >> tbl->it_page_shift; 211 unsigned long start = tbl->it_offset; 212 unsigned long end = start + tbl->it_size; 213 214 if ((start <= entry) && (entry < end)) { 215 *ptbl = tbl; 216 return i; 217 } 218 } 219 } 220 221 return -1; 222 } 223 224 static int tce_iommu_find_free_table(struct tce_container *container) 225 { 226 int i; 227 228 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 229 if (!container->tables[i]) 230 return i; 231 } 232 233 return -ENOSPC; 234 } 235 236 static int tce_iommu_enable(struct tce_container *container) 237 { 238 int ret = 0; 239 unsigned long locked; 240 struct iommu_table_group *table_group; 241 struct tce_iommu_group *tcegrp; 242 243 if (container->enabled) 244 return -EBUSY; 245 246 /* 247 * When userspace pages are mapped into the IOMMU, they are effectively 248 * locked memory, so, theoretically, we need to update the accounting 249 * of locked pages on each map and unmap. For powerpc, the map unmap 250 * paths can be very hot, though, and the accounting would kill 251 * performance, especially since it would be difficult to impossible 252 * to handle the accounting in real mode only. 253 * 254 * To address that, rather than precisely accounting every page, we 255 * instead account for a worst case on locked memory when the iommu is 256 * enabled and disabled. The worst case upper bound on locked memory 257 * is the size of the whole iommu window, which is usually relatively 258 * small (compared to total memory sizes) on POWER hardware. 259 * 260 * Also we don't have a nice way to fail on H_PUT_TCE due to ulimits, 261 * that would effectively kill the guest at random points, much better 262 * enforcing the limit based on the max that the guest can map. 263 * 264 * Unfortunately at the moment it counts whole tables, no matter how 265 * much memory the guest has. I.e. for 4GB guest and 4 IOMMU groups 266 * each with 2GB DMA window, 8GB will be counted here. The reason for 267 * this is that we cannot tell here the amount of RAM used by the guest 268 * as this information is only available from KVM and VFIO is 269 * KVM agnostic. 270 * 271 * So we do not allow enabling a container without a group attached 272 * as there is no way to know how much we should increment 273 * the locked_vm counter. 274 */ 275 if (!tce_groups_attached(container)) 276 return -ENODEV; 277 278 tcegrp = list_first_entry(&container->group_list, 279 struct tce_iommu_group, next); 280 table_group = iommu_group_get_iommudata(tcegrp->grp); 281 if (!table_group) 282 return -ENODEV; 283 284 if (!table_group->tce32_size) 285 return -EPERM; 286 287 ret = tce_iommu_mm_set(container); 288 if (ret) 289 return ret; 290 291 locked = table_group->tce32_size >> PAGE_SHIFT; 292 ret = account_locked_vm(container->mm, locked, true); 293 if (ret) 294 return ret; 295 296 container->locked_pages = locked; 297 298 container->enabled = true; 299 300 return ret; 301 } 302 303 static void tce_iommu_disable(struct tce_container *container) 304 { 305 if (!container->enabled) 306 return; 307 308 container->enabled = false; 309 310 BUG_ON(!container->mm); 311 account_locked_vm(container->mm, container->locked_pages, false); 312 } 313 314 static void *tce_iommu_open(unsigned long arg) 315 { 316 struct tce_container *container; 317 318 if ((arg != VFIO_SPAPR_TCE_IOMMU) && (arg != VFIO_SPAPR_TCE_v2_IOMMU)) { 319 pr_err("tce_vfio: Wrong IOMMU type\n"); 320 return ERR_PTR(-EINVAL); 321 } 322 323 container = kzalloc(sizeof(*container), GFP_KERNEL); 324 if (!container) 325 return ERR_PTR(-ENOMEM); 326 327 mutex_init(&container->lock); 328 INIT_LIST_HEAD_RCU(&container->group_list); 329 INIT_LIST_HEAD_RCU(&container->prereg_list); 330 331 container->v2 = arg == VFIO_SPAPR_TCE_v2_IOMMU; 332 333 return container; 334 } 335 336 static int tce_iommu_clear(struct tce_container *container, 337 struct iommu_table *tbl, 338 unsigned long entry, unsigned long pages); 339 static void tce_iommu_free_table(struct tce_container *container, 340 struct iommu_table *tbl); 341 342 static void tce_iommu_release(void *iommu_data) 343 { 344 struct tce_container *container = iommu_data; 345 struct tce_iommu_group *tcegrp; 346 struct tce_iommu_prereg *tcemem, *tmtmp; 347 long i; 348 349 while (tce_groups_attached(container)) { 350 tcegrp = list_first_entry(&container->group_list, 351 struct tce_iommu_group, next); 352 tce_iommu_detach_group(iommu_data, tcegrp->grp); 353 } 354 355 /* 356 * If VFIO created a table, it was not disposed 357 * by tce_iommu_detach_group() so do it now. 358 */ 359 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 360 struct iommu_table *tbl = container->tables[i]; 361 362 if (!tbl) 363 continue; 364 365 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size); 366 tce_iommu_free_table(container, tbl); 367 } 368 369 list_for_each_entry_safe(tcemem, tmtmp, &container->prereg_list, next) 370 WARN_ON(tce_iommu_prereg_free(container, tcemem)); 371 372 tce_iommu_disable(container); 373 if (container->mm) 374 mmdrop(container->mm); 375 mutex_destroy(&container->lock); 376 377 kfree(container); 378 } 379 380 static void tce_iommu_unuse_page(struct tce_container *container, 381 unsigned long hpa) 382 { 383 struct page *page; 384 385 page = pfn_to_page(hpa >> PAGE_SHIFT); 386 put_page(page); 387 } 388 389 static int tce_iommu_prereg_ua_to_hpa(struct tce_container *container, 390 unsigned long tce, unsigned long shift, 391 unsigned long *phpa, struct mm_iommu_table_group_mem_t **pmem) 392 { 393 long ret = 0; 394 struct mm_iommu_table_group_mem_t *mem; 395 396 mem = mm_iommu_lookup(container->mm, tce, 1ULL << shift); 397 if (!mem) 398 return -EINVAL; 399 400 ret = mm_iommu_ua_to_hpa(mem, tce, shift, phpa); 401 if (ret) 402 return -EINVAL; 403 404 *pmem = mem; 405 406 return 0; 407 } 408 409 static void tce_iommu_unuse_page_v2(struct tce_container *container, 410 struct iommu_table *tbl, unsigned long entry) 411 { 412 struct mm_iommu_table_group_mem_t *mem = NULL; 413 int ret; 414 unsigned long hpa = 0; 415 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl, entry); 416 417 if (!pua) 418 return; 419 420 ret = tce_iommu_prereg_ua_to_hpa(container, be64_to_cpu(*pua), 421 tbl->it_page_shift, &hpa, &mem); 422 if (ret) 423 pr_debug("%s: tce %llx at #%lx was not cached, ret=%d\n", 424 __func__, be64_to_cpu(*pua), entry, ret); 425 if (mem) 426 mm_iommu_mapped_dec(mem); 427 428 *pua = cpu_to_be64(0); 429 } 430 431 static int tce_iommu_clear(struct tce_container *container, 432 struct iommu_table *tbl, 433 unsigned long entry, unsigned long pages) 434 { 435 unsigned long oldhpa; 436 long ret; 437 enum dma_data_direction direction; 438 unsigned long lastentry = entry + pages; 439 440 for ( ; entry < lastentry; ++entry) { 441 if (tbl->it_indirect_levels && tbl->it_userspace) { 442 /* 443 * For multilevel tables, we can take a shortcut here 444 * and skip some TCEs as we know that the userspace 445 * addresses cache is a mirror of the real TCE table 446 * and if it is missing some indirect levels, then 447 * the hardware table does not have them allocated 448 * either and therefore does not require updating. 449 */ 450 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl, 451 entry); 452 if (!pua) { 453 /* align to level_size which is power of two */ 454 entry |= tbl->it_level_size - 1; 455 continue; 456 } 457 } 458 459 cond_resched(); 460 461 direction = DMA_NONE; 462 oldhpa = 0; 463 ret = iommu_tce_xchg(container->mm, tbl, entry, &oldhpa, 464 &direction); 465 if (ret) 466 continue; 467 468 if (direction == DMA_NONE) 469 continue; 470 471 if (container->v2) { 472 tce_iommu_unuse_page_v2(container, tbl, entry); 473 continue; 474 } 475 476 tce_iommu_unuse_page(container, oldhpa); 477 } 478 479 return 0; 480 } 481 482 static int tce_iommu_use_page(unsigned long tce, unsigned long *hpa) 483 { 484 struct page *page = NULL; 485 enum dma_data_direction direction = iommu_tce_direction(tce); 486 487 if (get_user_pages_fast(tce & PAGE_MASK, 1, 488 direction != DMA_TO_DEVICE ? FOLL_WRITE : 0, 489 &page) != 1) 490 return -EFAULT; 491 492 *hpa = __pa((unsigned long) page_address(page)); 493 494 return 0; 495 } 496 497 static long tce_iommu_build(struct tce_container *container, 498 struct iommu_table *tbl, 499 unsigned long entry, unsigned long tce, unsigned long pages, 500 enum dma_data_direction direction) 501 { 502 long i, ret = 0; 503 unsigned long hpa; 504 enum dma_data_direction dirtmp; 505 506 for (i = 0; i < pages; ++i) { 507 unsigned long offset = tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK; 508 509 ret = tce_iommu_use_page(tce, &hpa); 510 if (ret) 511 break; 512 513 if (!tce_page_is_contained(container->mm, hpa, 514 tbl->it_page_shift)) { 515 ret = -EPERM; 516 break; 517 } 518 519 hpa |= offset; 520 dirtmp = direction; 521 ret = iommu_tce_xchg(container->mm, tbl, entry + i, &hpa, 522 &dirtmp); 523 if (ret) { 524 tce_iommu_unuse_page(container, hpa); 525 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n", 526 __func__, entry << tbl->it_page_shift, 527 tce, ret); 528 break; 529 } 530 531 if (dirtmp != DMA_NONE) 532 tce_iommu_unuse_page(container, hpa); 533 534 tce += IOMMU_PAGE_SIZE(tbl); 535 } 536 537 if (ret) 538 tce_iommu_clear(container, tbl, entry, i); 539 540 return ret; 541 } 542 543 static long tce_iommu_build_v2(struct tce_container *container, 544 struct iommu_table *tbl, 545 unsigned long entry, unsigned long tce, unsigned long pages, 546 enum dma_data_direction direction) 547 { 548 long i, ret = 0; 549 unsigned long hpa; 550 enum dma_data_direction dirtmp; 551 552 for (i = 0; i < pages; ++i) { 553 struct mm_iommu_table_group_mem_t *mem = NULL; 554 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry + i); 555 556 ret = tce_iommu_prereg_ua_to_hpa(container, 557 tce, tbl->it_page_shift, &hpa, &mem); 558 if (ret) 559 break; 560 561 if (!tce_page_is_contained(container->mm, hpa, 562 tbl->it_page_shift)) { 563 ret = -EPERM; 564 break; 565 } 566 567 /* Preserve offset within IOMMU page */ 568 hpa |= tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK; 569 dirtmp = direction; 570 571 /* The registered region is being unregistered */ 572 if (mm_iommu_mapped_inc(mem)) 573 break; 574 575 ret = iommu_tce_xchg(container->mm, tbl, entry + i, &hpa, 576 &dirtmp); 577 if (ret) { 578 /* dirtmp cannot be DMA_NONE here */ 579 tce_iommu_unuse_page_v2(container, tbl, entry + i); 580 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n", 581 __func__, entry << tbl->it_page_shift, 582 tce, ret); 583 break; 584 } 585 586 if (dirtmp != DMA_NONE) 587 tce_iommu_unuse_page_v2(container, tbl, entry + i); 588 589 *pua = cpu_to_be64(tce); 590 591 tce += IOMMU_PAGE_SIZE(tbl); 592 } 593 594 if (ret) 595 tce_iommu_clear(container, tbl, entry, i); 596 597 return ret; 598 } 599 600 static long tce_iommu_create_table(struct tce_container *container, 601 struct iommu_table_group *table_group, 602 int num, 603 __u32 page_shift, 604 __u64 window_size, 605 __u32 levels, 606 struct iommu_table **ptbl) 607 { 608 long ret, table_size; 609 610 table_size = table_group->ops->get_table_size(page_shift, window_size, 611 levels); 612 if (!table_size) 613 return -EINVAL; 614 615 ret = account_locked_vm(container->mm, table_size >> PAGE_SHIFT, true); 616 if (ret) 617 return ret; 618 619 ret = table_group->ops->create_table(table_group, num, 620 page_shift, window_size, levels, ptbl); 621 622 WARN_ON(!ret && !(*ptbl)->it_ops->free); 623 WARN_ON(!ret && ((*ptbl)->it_allocated_size > table_size)); 624 625 return ret; 626 } 627 628 static void tce_iommu_free_table(struct tce_container *container, 629 struct iommu_table *tbl) 630 { 631 unsigned long pages = tbl->it_allocated_size >> PAGE_SHIFT; 632 633 iommu_tce_table_put(tbl); 634 account_locked_vm(container->mm, pages, false); 635 } 636 637 static long tce_iommu_create_window(struct tce_container *container, 638 __u32 page_shift, __u64 window_size, __u32 levels, 639 __u64 *start_addr) 640 { 641 struct tce_iommu_group *tcegrp; 642 struct iommu_table_group *table_group; 643 struct iommu_table *tbl = NULL; 644 long ret, num; 645 646 num = tce_iommu_find_free_table(container); 647 if (num < 0) 648 return num; 649 650 /* Get the first group for ops::create_table */ 651 tcegrp = list_first_entry(&container->group_list, 652 struct tce_iommu_group, next); 653 table_group = iommu_group_get_iommudata(tcegrp->grp); 654 if (!table_group) 655 return -EFAULT; 656 657 if (!(table_group->pgsizes & (1ULL << page_shift))) 658 return -EINVAL; 659 660 if (!table_group->ops->set_window || !table_group->ops->unset_window || 661 !table_group->ops->get_table_size || 662 !table_group->ops->create_table) 663 return -EPERM; 664 665 /* Create TCE table */ 666 ret = tce_iommu_create_table(container, table_group, num, 667 page_shift, window_size, levels, &tbl); 668 if (ret) 669 return ret; 670 671 BUG_ON(!tbl->it_ops->free); 672 673 /* 674 * Program the table to every group. 675 * Groups have been tested for compatibility at the attach time. 676 */ 677 list_for_each_entry(tcegrp, &container->group_list, next) { 678 table_group = iommu_group_get_iommudata(tcegrp->grp); 679 680 ret = table_group->ops->set_window(table_group, num, tbl); 681 if (ret) 682 goto unset_exit; 683 } 684 685 container->tables[num] = tbl; 686 687 /* Return start address assigned by platform in create_table() */ 688 *start_addr = tbl->it_offset << tbl->it_page_shift; 689 690 return 0; 691 692 unset_exit: 693 list_for_each_entry(tcegrp, &container->group_list, next) { 694 table_group = iommu_group_get_iommudata(tcegrp->grp); 695 table_group->ops->unset_window(table_group, num); 696 } 697 tce_iommu_free_table(container, tbl); 698 699 return ret; 700 } 701 702 static long tce_iommu_remove_window(struct tce_container *container, 703 __u64 start_addr) 704 { 705 struct iommu_table_group *table_group = NULL; 706 struct iommu_table *tbl; 707 struct tce_iommu_group *tcegrp; 708 int num; 709 710 num = tce_iommu_find_table(container, start_addr, &tbl); 711 if (num < 0) 712 return -EINVAL; 713 714 BUG_ON(!tbl->it_size); 715 716 /* Detach groups from IOMMUs */ 717 list_for_each_entry(tcegrp, &container->group_list, next) { 718 table_group = iommu_group_get_iommudata(tcegrp->grp); 719 720 /* 721 * SPAPR TCE IOMMU exposes the default DMA window to 722 * the guest via dma32_window_start/size of 723 * VFIO_IOMMU_SPAPR_TCE_GET_INFO. Some platforms allow 724 * the userspace to remove this window, some do not so 725 * here we check for the platform capability. 726 */ 727 if (!table_group->ops || !table_group->ops->unset_window) 728 return -EPERM; 729 730 table_group->ops->unset_window(table_group, num); 731 } 732 733 /* Free table */ 734 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size); 735 tce_iommu_free_table(container, tbl); 736 container->tables[num] = NULL; 737 738 return 0; 739 } 740 741 static long tce_iommu_create_default_window(struct tce_container *container) 742 { 743 long ret; 744 __u64 start_addr = 0; 745 struct tce_iommu_group *tcegrp; 746 struct iommu_table_group *table_group; 747 748 if (!container->def_window_pending) 749 return 0; 750 751 if (!tce_groups_attached(container)) 752 return -ENODEV; 753 754 tcegrp = list_first_entry(&container->group_list, 755 struct tce_iommu_group, next); 756 table_group = iommu_group_get_iommudata(tcegrp->grp); 757 if (!table_group) 758 return -ENODEV; 759 760 ret = tce_iommu_create_window(container, IOMMU_PAGE_SHIFT_4K, 761 table_group->tce32_size, 1, &start_addr); 762 WARN_ON_ONCE(!ret && start_addr); 763 764 if (!ret) 765 container->def_window_pending = false; 766 767 return ret; 768 } 769 770 static long tce_iommu_ioctl(void *iommu_data, 771 unsigned int cmd, unsigned long arg) 772 { 773 struct tce_container *container = iommu_data; 774 unsigned long minsz, ddwsz; 775 long ret; 776 777 switch (cmd) { 778 case VFIO_CHECK_EXTENSION: 779 switch (arg) { 780 case VFIO_SPAPR_TCE_IOMMU: 781 case VFIO_SPAPR_TCE_v2_IOMMU: 782 ret = 1; 783 break; 784 default: 785 ret = vfio_spapr_iommu_eeh_ioctl(NULL, cmd, arg); 786 break; 787 } 788 789 return (ret < 0) ? 0 : ret; 790 } 791 792 /* 793 * Sanity check to prevent one userspace from manipulating 794 * another userspace mm. 795 */ 796 BUG_ON(!container); 797 if (container->mm && container->mm != current->mm) 798 return -EPERM; 799 800 switch (cmd) { 801 case VFIO_IOMMU_SPAPR_TCE_GET_INFO: { 802 struct vfio_iommu_spapr_tce_info info; 803 struct tce_iommu_group *tcegrp; 804 struct iommu_table_group *table_group; 805 806 if (!tce_groups_attached(container)) 807 return -ENXIO; 808 809 tcegrp = list_first_entry(&container->group_list, 810 struct tce_iommu_group, next); 811 table_group = iommu_group_get_iommudata(tcegrp->grp); 812 813 if (!table_group) 814 return -ENXIO; 815 816 minsz = offsetofend(struct vfio_iommu_spapr_tce_info, 817 dma32_window_size); 818 819 if (copy_from_user(&info, (void __user *)arg, minsz)) 820 return -EFAULT; 821 822 if (info.argsz < minsz) 823 return -EINVAL; 824 825 info.dma32_window_start = table_group->tce32_start; 826 info.dma32_window_size = table_group->tce32_size; 827 info.flags = 0; 828 memset(&info.ddw, 0, sizeof(info.ddw)); 829 830 if (table_group->max_dynamic_windows_supported && 831 container->v2) { 832 info.flags |= VFIO_IOMMU_SPAPR_INFO_DDW; 833 info.ddw.pgsizes = table_group->pgsizes; 834 info.ddw.max_dynamic_windows_supported = 835 table_group->max_dynamic_windows_supported; 836 info.ddw.levels = table_group->max_levels; 837 } 838 839 ddwsz = offsetofend(struct vfio_iommu_spapr_tce_info, ddw); 840 841 if (info.argsz >= ddwsz) 842 minsz = ddwsz; 843 844 if (copy_to_user((void __user *)arg, &info, minsz)) 845 return -EFAULT; 846 847 return 0; 848 } 849 case VFIO_IOMMU_MAP_DMA: { 850 struct vfio_iommu_type1_dma_map param; 851 struct iommu_table *tbl = NULL; 852 long num; 853 enum dma_data_direction direction; 854 855 if (!container->enabled) 856 return -EPERM; 857 858 minsz = offsetofend(struct vfio_iommu_type1_dma_map, size); 859 860 if (copy_from_user(¶m, (void __user *)arg, minsz)) 861 return -EFAULT; 862 863 if (param.argsz < minsz) 864 return -EINVAL; 865 866 if (param.flags & ~(VFIO_DMA_MAP_FLAG_READ | 867 VFIO_DMA_MAP_FLAG_WRITE)) 868 return -EINVAL; 869 870 ret = tce_iommu_create_default_window(container); 871 if (ret) 872 return ret; 873 874 num = tce_iommu_find_table(container, param.iova, &tbl); 875 if (num < 0) 876 return -ENXIO; 877 878 if ((param.size & ~IOMMU_PAGE_MASK(tbl)) || 879 (param.vaddr & ~IOMMU_PAGE_MASK(tbl))) 880 return -EINVAL; 881 882 /* iova is checked by the IOMMU API */ 883 if (param.flags & VFIO_DMA_MAP_FLAG_READ) { 884 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE) 885 direction = DMA_BIDIRECTIONAL; 886 else 887 direction = DMA_TO_DEVICE; 888 } else { 889 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE) 890 direction = DMA_FROM_DEVICE; 891 else 892 return -EINVAL; 893 } 894 895 ret = iommu_tce_put_param_check(tbl, param.iova, param.vaddr); 896 if (ret) 897 return ret; 898 899 if (container->v2) 900 ret = tce_iommu_build_v2(container, tbl, 901 param.iova >> tbl->it_page_shift, 902 param.vaddr, 903 param.size >> tbl->it_page_shift, 904 direction); 905 else 906 ret = tce_iommu_build(container, tbl, 907 param.iova >> tbl->it_page_shift, 908 param.vaddr, 909 param.size >> tbl->it_page_shift, 910 direction); 911 912 iommu_flush_tce(tbl); 913 914 return ret; 915 } 916 case VFIO_IOMMU_UNMAP_DMA: { 917 struct vfio_iommu_type1_dma_unmap param; 918 struct iommu_table *tbl = NULL; 919 long num; 920 921 if (!container->enabled) 922 return -EPERM; 923 924 minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, 925 size); 926 927 if (copy_from_user(¶m, (void __user *)arg, minsz)) 928 return -EFAULT; 929 930 if (param.argsz < minsz) 931 return -EINVAL; 932 933 /* No flag is supported now */ 934 if (param.flags) 935 return -EINVAL; 936 937 ret = tce_iommu_create_default_window(container); 938 if (ret) 939 return ret; 940 941 num = tce_iommu_find_table(container, param.iova, &tbl); 942 if (num < 0) 943 return -ENXIO; 944 945 if (param.size & ~IOMMU_PAGE_MASK(tbl)) 946 return -EINVAL; 947 948 ret = iommu_tce_clear_param_check(tbl, param.iova, 0, 949 param.size >> tbl->it_page_shift); 950 if (ret) 951 return ret; 952 953 ret = tce_iommu_clear(container, tbl, 954 param.iova >> tbl->it_page_shift, 955 param.size >> tbl->it_page_shift); 956 iommu_flush_tce(tbl); 957 958 return ret; 959 } 960 case VFIO_IOMMU_SPAPR_REGISTER_MEMORY: { 961 struct vfio_iommu_spapr_register_memory param; 962 963 if (!container->v2) 964 break; 965 966 minsz = offsetofend(struct vfio_iommu_spapr_register_memory, 967 size); 968 969 ret = tce_iommu_mm_set(container); 970 if (ret) 971 return ret; 972 973 if (copy_from_user(¶m, (void __user *)arg, minsz)) 974 return -EFAULT; 975 976 if (param.argsz < minsz) 977 return -EINVAL; 978 979 /* No flag is supported now */ 980 if (param.flags) 981 return -EINVAL; 982 983 mutex_lock(&container->lock); 984 ret = tce_iommu_register_pages(container, param.vaddr, 985 param.size); 986 mutex_unlock(&container->lock); 987 988 return ret; 989 } 990 case VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY: { 991 struct vfio_iommu_spapr_register_memory param; 992 993 if (!container->v2) 994 break; 995 996 if (!container->mm) 997 return -EPERM; 998 999 minsz = offsetofend(struct vfio_iommu_spapr_register_memory, 1000 size); 1001 1002 if (copy_from_user(¶m, (void __user *)arg, minsz)) 1003 return -EFAULT; 1004 1005 if (param.argsz < minsz) 1006 return -EINVAL; 1007 1008 /* No flag is supported now */ 1009 if (param.flags) 1010 return -EINVAL; 1011 1012 mutex_lock(&container->lock); 1013 ret = tce_iommu_unregister_pages(container, param.vaddr, 1014 param.size); 1015 mutex_unlock(&container->lock); 1016 1017 return ret; 1018 } 1019 case VFIO_IOMMU_ENABLE: 1020 if (container->v2) 1021 break; 1022 1023 mutex_lock(&container->lock); 1024 ret = tce_iommu_enable(container); 1025 mutex_unlock(&container->lock); 1026 return ret; 1027 1028 1029 case VFIO_IOMMU_DISABLE: 1030 if (container->v2) 1031 break; 1032 1033 mutex_lock(&container->lock); 1034 tce_iommu_disable(container); 1035 mutex_unlock(&container->lock); 1036 return 0; 1037 1038 case VFIO_EEH_PE_OP: { 1039 struct tce_iommu_group *tcegrp; 1040 1041 ret = 0; 1042 list_for_each_entry(tcegrp, &container->group_list, next) { 1043 ret = vfio_spapr_iommu_eeh_ioctl(tcegrp->grp, 1044 cmd, arg); 1045 if (ret) 1046 return ret; 1047 } 1048 return ret; 1049 } 1050 1051 case VFIO_IOMMU_SPAPR_TCE_CREATE: { 1052 struct vfio_iommu_spapr_tce_create create; 1053 1054 if (!container->v2) 1055 break; 1056 1057 ret = tce_iommu_mm_set(container); 1058 if (ret) 1059 return ret; 1060 1061 if (!tce_groups_attached(container)) 1062 return -ENXIO; 1063 1064 minsz = offsetofend(struct vfio_iommu_spapr_tce_create, 1065 start_addr); 1066 1067 if (copy_from_user(&create, (void __user *)arg, minsz)) 1068 return -EFAULT; 1069 1070 if (create.argsz < minsz) 1071 return -EINVAL; 1072 1073 if (create.flags) 1074 return -EINVAL; 1075 1076 mutex_lock(&container->lock); 1077 1078 ret = tce_iommu_create_default_window(container); 1079 if (!ret) 1080 ret = tce_iommu_create_window(container, 1081 create.page_shift, 1082 create.window_size, create.levels, 1083 &create.start_addr); 1084 1085 mutex_unlock(&container->lock); 1086 1087 if (!ret && copy_to_user((void __user *)arg, &create, minsz)) 1088 ret = -EFAULT; 1089 1090 return ret; 1091 } 1092 case VFIO_IOMMU_SPAPR_TCE_REMOVE: { 1093 struct vfio_iommu_spapr_tce_remove remove; 1094 1095 if (!container->v2) 1096 break; 1097 1098 ret = tce_iommu_mm_set(container); 1099 if (ret) 1100 return ret; 1101 1102 if (!tce_groups_attached(container)) 1103 return -ENXIO; 1104 1105 minsz = offsetofend(struct vfio_iommu_spapr_tce_remove, 1106 start_addr); 1107 1108 if (copy_from_user(&remove, (void __user *)arg, minsz)) 1109 return -EFAULT; 1110 1111 if (remove.argsz < minsz) 1112 return -EINVAL; 1113 1114 if (remove.flags) 1115 return -EINVAL; 1116 1117 if (container->def_window_pending && !remove.start_addr) { 1118 container->def_window_pending = false; 1119 return 0; 1120 } 1121 1122 mutex_lock(&container->lock); 1123 1124 ret = tce_iommu_remove_window(container, remove.start_addr); 1125 1126 mutex_unlock(&container->lock); 1127 1128 return ret; 1129 } 1130 } 1131 1132 return -ENOTTY; 1133 } 1134 1135 static void tce_iommu_release_ownership(struct tce_container *container, 1136 struct iommu_table_group *table_group) 1137 { 1138 int i; 1139 1140 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 1141 struct iommu_table *tbl = container->tables[i]; 1142 1143 if (!tbl) 1144 continue; 1145 1146 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size); 1147 if (tbl->it_map) 1148 iommu_release_ownership(tbl); 1149 1150 container->tables[i] = NULL; 1151 } 1152 } 1153 1154 static int tce_iommu_take_ownership(struct tce_container *container, 1155 struct iommu_table_group *table_group) 1156 { 1157 int i, j, rc = 0; 1158 1159 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 1160 struct iommu_table *tbl = table_group->tables[i]; 1161 1162 if (!tbl || !tbl->it_map) 1163 continue; 1164 1165 rc = iommu_take_ownership(tbl); 1166 if (rc) { 1167 for (j = 0; j < i; ++j) 1168 iommu_release_ownership( 1169 table_group->tables[j]); 1170 1171 return rc; 1172 } 1173 } 1174 1175 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) 1176 container->tables[i] = table_group->tables[i]; 1177 1178 return 0; 1179 } 1180 1181 static void tce_iommu_release_ownership_ddw(struct tce_container *container, 1182 struct iommu_table_group *table_group) 1183 { 1184 long i; 1185 1186 if (!table_group->ops->unset_window) { 1187 WARN_ON_ONCE(1); 1188 return; 1189 } 1190 1191 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) 1192 if (container->tables[i]) 1193 table_group->ops->unset_window(table_group, i); 1194 1195 table_group->ops->release_ownership(table_group); 1196 } 1197 1198 static long tce_iommu_take_ownership_ddw(struct tce_container *container, 1199 struct iommu_table_group *table_group) 1200 { 1201 long i, ret = 0; 1202 1203 if (!table_group->ops->create_table || !table_group->ops->set_window || 1204 !table_group->ops->release_ownership) { 1205 WARN_ON_ONCE(1); 1206 return -EFAULT; 1207 } 1208 1209 table_group->ops->take_ownership(table_group); 1210 1211 /* Set all windows to the new group */ 1212 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 1213 struct iommu_table *tbl = container->tables[i]; 1214 1215 if (!tbl) 1216 continue; 1217 1218 ret = table_group->ops->set_window(table_group, i, tbl); 1219 if (ret) 1220 goto release_exit; 1221 } 1222 1223 return 0; 1224 1225 release_exit: 1226 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) 1227 table_group->ops->unset_window(table_group, i); 1228 1229 table_group->ops->release_ownership(table_group); 1230 1231 return ret; 1232 } 1233 1234 static int tce_iommu_attach_group(void *iommu_data, 1235 struct iommu_group *iommu_group) 1236 { 1237 int ret; 1238 struct tce_container *container = iommu_data; 1239 struct iommu_table_group *table_group; 1240 struct tce_iommu_group *tcegrp = NULL; 1241 1242 mutex_lock(&container->lock); 1243 1244 /* pr_debug("tce_vfio: Attaching group #%u to iommu %p\n", 1245 iommu_group_id(iommu_group), iommu_group); */ 1246 table_group = iommu_group_get_iommudata(iommu_group); 1247 if (!table_group) { 1248 ret = -ENODEV; 1249 goto unlock_exit; 1250 } 1251 1252 if (tce_groups_attached(container) && (!table_group->ops || 1253 !table_group->ops->take_ownership || 1254 !table_group->ops->release_ownership)) { 1255 ret = -EBUSY; 1256 goto unlock_exit; 1257 } 1258 1259 /* Check if new group has the same iommu_ops (i.e. compatible) */ 1260 list_for_each_entry(tcegrp, &container->group_list, next) { 1261 struct iommu_table_group *table_group_tmp; 1262 1263 if (tcegrp->grp == iommu_group) { 1264 pr_warn("tce_vfio: Group %d is already attached\n", 1265 iommu_group_id(iommu_group)); 1266 ret = -EBUSY; 1267 goto unlock_exit; 1268 } 1269 table_group_tmp = iommu_group_get_iommudata(tcegrp->grp); 1270 if (table_group_tmp->ops->create_table != 1271 table_group->ops->create_table) { 1272 pr_warn("tce_vfio: Group %d is incompatible with group %d\n", 1273 iommu_group_id(iommu_group), 1274 iommu_group_id(tcegrp->grp)); 1275 ret = -EPERM; 1276 goto unlock_exit; 1277 } 1278 } 1279 1280 tcegrp = kzalloc(sizeof(*tcegrp), GFP_KERNEL); 1281 if (!tcegrp) { 1282 ret = -ENOMEM; 1283 goto unlock_exit; 1284 } 1285 1286 if (!table_group->ops || !table_group->ops->take_ownership || 1287 !table_group->ops->release_ownership) { 1288 if (container->v2) { 1289 ret = -EPERM; 1290 goto unlock_exit; 1291 } 1292 ret = tce_iommu_take_ownership(container, table_group); 1293 } else { 1294 if (!container->v2) { 1295 ret = -EPERM; 1296 goto unlock_exit; 1297 } 1298 ret = tce_iommu_take_ownership_ddw(container, table_group); 1299 if (!tce_groups_attached(container) && !container->tables[0]) 1300 container->def_window_pending = true; 1301 } 1302 1303 if (!ret) { 1304 tcegrp->grp = iommu_group; 1305 list_add(&tcegrp->next, &container->group_list); 1306 } 1307 1308 unlock_exit: 1309 if (ret && tcegrp) 1310 kfree(tcegrp); 1311 1312 mutex_unlock(&container->lock); 1313 1314 return ret; 1315 } 1316 1317 static void tce_iommu_detach_group(void *iommu_data, 1318 struct iommu_group *iommu_group) 1319 { 1320 struct tce_container *container = iommu_data; 1321 struct iommu_table_group *table_group; 1322 bool found = false; 1323 struct tce_iommu_group *tcegrp; 1324 1325 mutex_lock(&container->lock); 1326 1327 list_for_each_entry(tcegrp, &container->group_list, next) { 1328 if (tcegrp->grp == iommu_group) { 1329 found = true; 1330 break; 1331 } 1332 } 1333 1334 if (!found) { 1335 pr_warn("tce_vfio: detaching unattached group #%u\n", 1336 iommu_group_id(iommu_group)); 1337 goto unlock_exit; 1338 } 1339 1340 list_del(&tcegrp->next); 1341 kfree(tcegrp); 1342 1343 table_group = iommu_group_get_iommudata(iommu_group); 1344 BUG_ON(!table_group); 1345 1346 if (!table_group->ops || !table_group->ops->release_ownership) 1347 tce_iommu_release_ownership(container, table_group); 1348 else 1349 tce_iommu_release_ownership_ddw(container, table_group); 1350 1351 unlock_exit: 1352 mutex_unlock(&container->lock); 1353 } 1354 1355 static const struct vfio_iommu_driver_ops tce_iommu_driver_ops = { 1356 .name = "iommu-vfio-powerpc", 1357 .owner = THIS_MODULE, 1358 .open = tce_iommu_open, 1359 .release = tce_iommu_release, 1360 .ioctl = tce_iommu_ioctl, 1361 .attach_group = tce_iommu_attach_group, 1362 .detach_group = tce_iommu_detach_group, 1363 }; 1364 1365 static int __init tce_iommu_init(void) 1366 { 1367 return vfio_register_iommu_driver(&tce_iommu_driver_ops); 1368 } 1369 1370 static void __exit tce_iommu_cleanup(void) 1371 { 1372 vfio_unregister_iommu_driver(&tce_iommu_driver_ops); 1373 } 1374 1375 module_init(tce_iommu_init); 1376 module_exit(tce_iommu_cleanup); 1377 1378 MODULE_VERSION(DRIVER_VERSION); 1379 MODULE_LICENSE("GPL v2"); 1380 MODULE_AUTHOR(DRIVER_AUTHOR); 1381 MODULE_DESCRIPTION(DRIVER_DESC); 1382 1383