1 /* 2 * VFIO: IOMMU DMA mapping support for TCE on POWER 3 * 4 * Copyright (C) 2013 IBM Corp. All rights reserved. 5 * Author: Alexey Kardashevskiy <aik@ozlabs.ru> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * Derived from original vfio_iommu_type1.c: 12 * Copyright (C) 2012 Red Hat, Inc. All rights reserved. 13 * Author: Alex Williamson <alex.williamson@redhat.com> 14 */ 15 16 #include <linux/module.h> 17 #include <linux/pci.h> 18 #include <linux/slab.h> 19 #include <linux/uaccess.h> 20 #include <linux/err.h> 21 #include <linux/vfio.h> 22 #include <linux/vmalloc.h> 23 #include <linux/sched/mm.h> 24 #include <linux/sched/signal.h> 25 26 #include <asm/iommu.h> 27 #include <asm/tce.h> 28 #include <asm/mmu_context.h> 29 30 #define DRIVER_VERSION "0.1" 31 #define DRIVER_AUTHOR "aik@ozlabs.ru" 32 #define DRIVER_DESC "VFIO IOMMU SPAPR TCE" 33 34 static void tce_iommu_detach_group(void *iommu_data, 35 struct iommu_group *iommu_group); 36 37 static long try_increment_locked_vm(struct mm_struct *mm, long npages) 38 { 39 long ret = 0, locked, lock_limit; 40 41 if (WARN_ON_ONCE(!mm)) 42 return -EPERM; 43 44 if (!npages) 45 return 0; 46 47 down_write(&mm->mmap_sem); 48 locked = mm->locked_vm + npages; 49 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 50 if (locked > lock_limit && !capable(CAP_IPC_LOCK)) 51 ret = -ENOMEM; 52 else 53 mm->locked_vm += npages; 54 55 pr_debug("[%d] RLIMIT_MEMLOCK +%ld %ld/%ld%s\n", current->pid, 56 npages << PAGE_SHIFT, 57 mm->locked_vm << PAGE_SHIFT, 58 rlimit(RLIMIT_MEMLOCK), 59 ret ? " - exceeded" : ""); 60 61 up_write(&mm->mmap_sem); 62 63 return ret; 64 } 65 66 static void decrement_locked_vm(struct mm_struct *mm, long npages) 67 { 68 if (!mm || !npages) 69 return; 70 71 down_write(&mm->mmap_sem); 72 if (WARN_ON_ONCE(npages > mm->locked_vm)) 73 npages = mm->locked_vm; 74 mm->locked_vm -= npages; 75 pr_debug("[%d] RLIMIT_MEMLOCK -%ld %ld/%ld\n", current->pid, 76 npages << PAGE_SHIFT, 77 mm->locked_vm << PAGE_SHIFT, 78 rlimit(RLIMIT_MEMLOCK)); 79 up_write(&mm->mmap_sem); 80 } 81 82 /* 83 * VFIO IOMMU fd for SPAPR_TCE IOMMU implementation 84 * 85 * This code handles mapping and unmapping of user data buffers 86 * into DMA'ble space using the IOMMU 87 */ 88 89 struct tce_iommu_group { 90 struct list_head next; 91 struct iommu_group *grp; 92 }; 93 94 /* 95 * A container needs to remember which preregistered region it has 96 * referenced to do proper cleanup at the userspace process exit. 97 */ 98 struct tce_iommu_prereg { 99 struct list_head next; 100 struct mm_iommu_table_group_mem_t *mem; 101 }; 102 103 /* 104 * The container descriptor supports only a single group per container. 105 * Required by the API as the container is not supplied with the IOMMU group 106 * at the moment of initialization. 107 */ 108 struct tce_container { 109 struct mutex lock; 110 bool enabled; 111 bool v2; 112 bool def_window_pending; 113 unsigned long locked_pages; 114 struct mm_struct *mm; 115 struct iommu_table *tables[IOMMU_TABLE_GROUP_MAX_TABLES]; 116 struct list_head group_list; 117 struct list_head prereg_list; 118 }; 119 120 static long tce_iommu_mm_set(struct tce_container *container) 121 { 122 if (container->mm) { 123 if (container->mm == current->mm) 124 return 0; 125 return -EPERM; 126 } 127 BUG_ON(!current->mm); 128 container->mm = current->mm; 129 atomic_inc(&container->mm->mm_count); 130 131 return 0; 132 } 133 134 static long tce_iommu_prereg_free(struct tce_container *container, 135 struct tce_iommu_prereg *tcemem) 136 { 137 long ret; 138 139 ret = mm_iommu_put(container->mm, tcemem->mem); 140 if (ret) 141 return ret; 142 143 list_del(&tcemem->next); 144 kfree(tcemem); 145 146 return 0; 147 } 148 149 static long tce_iommu_unregister_pages(struct tce_container *container, 150 __u64 vaddr, __u64 size) 151 { 152 struct mm_iommu_table_group_mem_t *mem; 153 struct tce_iommu_prereg *tcemem; 154 bool found = false; 155 156 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK)) 157 return -EINVAL; 158 159 mem = mm_iommu_find(container->mm, vaddr, size >> PAGE_SHIFT); 160 if (!mem) 161 return -ENOENT; 162 163 list_for_each_entry(tcemem, &container->prereg_list, next) { 164 if (tcemem->mem == mem) { 165 found = true; 166 break; 167 } 168 } 169 170 if (!found) 171 return -ENOENT; 172 173 return tce_iommu_prereg_free(container, tcemem); 174 } 175 176 static long tce_iommu_register_pages(struct tce_container *container, 177 __u64 vaddr, __u64 size) 178 { 179 long ret = 0; 180 struct mm_iommu_table_group_mem_t *mem = NULL; 181 struct tce_iommu_prereg *tcemem; 182 unsigned long entries = size >> PAGE_SHIFT; 183 184 if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK) || 185 ((vaddr + size) < vaddr)) 186 return -EINVAL; 187 188 mem = mm_iommu_find(container->mm, vaddr, entries); 189 if (mem) { 190 list_for_each_entry(tcemem, &container->prereg_list, next) { 191 if (tcemem->mem == mem) 192 return -EBUSY; 193 } 194 } 195 196 ret = mm_iommu_get(container->mm, vaddr, entries, &mem); 197 if (ret) 198 return ret; 199 200 tcemem = kzalloc(sizeof(*tcemem), GFP_KERNEL); 201 if (!tcemem) { 202 mm_iommu_put(container->mm, mem); 203 return -ENOMEM; 204 } 205 206 tcemem->mem = mem; 207 list_add(&tcemem->next, &container->prereg_list); 208 209 container->enabled = true; 210 211 return 0; 212 } 213 214 static bool tce_page_is_contained(struct page *page, unsigned page_shift) 215 { 216 /* 217 * Check that the TCE table granularity is not bigger than the size of 218 * a page we just found. Otherwise the hardware can get access to 219 * a bigger memory chunk that it should. 220 */ 221 return (PAGE_SHIFT + compound_order(compound_head(page))) >= page_shift; 222 } 223 224 static inline bool tce_groups_attached(struct tce_container *container) 225 { 226 return !list_empty(&container->group_list); 227 } 228 229 static long tce_iommu_find_table(struct tce_container *container, 230 phys_addr_t ioba, struct iommu_table **ptbl) 231 { 232 long i; 233 234 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 235 struct iommu_table *tbl = container->tables[i]; 236 237 if (tbl) { 238 unsigned long entry = ioba >> tbl->it_page_shift; 239 unsigned long start = tbl->it_offset; 240 unsigned long end = start + tbl->it_size; 241 242 if ((start <= entry) && (entry < end)) { 243 *ptbl = tbl; 244 return i; 245 } 246 } 247 } 248 249 return -1; 250 } 251 252 static int tce_iommu_find_free_table(struct tce_container *container) 253 { 254 int i; 255 256 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 257 if (!container->tables[i]) 258 return i; 259 } 260 261 return -ENOSPC; 262 } 263 264 static int tce_iommu_enable(struct tce_container *container) 265 { 266 int ret = 0; 267 unsigned long locked; 268 struct iommu_table_group *table_group; 269 struct tce_iommu_group *tcegrp; 270 271 if (container->enabled) 272 return -EBUSY; 273 274 /* 275 * When userspace pages are mapped into the IOMMU, they are effectively 276 * locked memory, so, theoretically, we need to update the accounting 277 * of locked pages on each map and unmap. For powerpc, the map unmap 278 * paths can be very hot, though, and the accounting would kill 279 * performance, especially since it would be difficult to impossible 280 * to handle the accounting in real mode only. 281 * 282 * To address that, rather than precisely accounting every page, we 283 * instead account for a worst case on locked memory when the iommu is 284 * enabled and disabled. The worst case upper bound on locked memory 285 * is the size of the whole iommu window, which is usually relatively 286 * small (compared to total memory sizes) on POWER hardware. 287 * 288 * Also we don't have a nice way to fail on H_PUT_TCE due to ulimits, 289 * that would effectively kill the guest at random points, much better 290 * enforcing the limit based on the max that the guest can map. 291 * 292 * Unfortunately at the moment it counts whole tables, no matter how 293 * much memory the guest has. I.e. for 4GB guest and 4 IOMMU groups 294 * each with 2GB DMA window, 8GB will be counted here. The reason for 295 * this is that we cannot tell here the amount of RAM used by the guest 296 * as this information is only available from KVM and VFIO is 297 * KVM agnostic. 298 * 299 * So we do not allow enabling a container without a group attached 300 * as there is no way to know how much we should increment 301 * the locked_vm counter. 302 */ 303 if (!tce_groups_attached(container)) 304 return -ENODEV; 305 306 tcegrp = list_first_entry(&container->group_list, 307 struct tce_iommu_group, next); 308 table_group = iommu_group_get_iommudata(tcegrp->grp); 309 if (!table_group) 310 return -ENODEV; 311 312 if (!table_group->tce32_size) 313 return -EPERM; 314 315 ret = tce_iommu_mm_set(container); 316 if (ret) 317 return ret; 318 319 locked = table_group->tce32_size >> PAGE_SHIFT; 320 ret = try_increment_locked_vm(container->mm, locked); 321 if (ret) 322 return ret; 323 324 container->locked_pages = locked; 325 326 container->enabled = true; 327 328 return ret; 329 } 330 331 static void tce_iommu_disable(struct tce_container *container) 332 { 333 if (!container->enabled) 334 return; 335 336 container->enabled = false; 337 338 BUG_ON(!container->mm); 339 decrement_locked_vm(container->mm, container->locked_pages); 340 } 341 342 static void *tce_iommu_open(unsigned long arg) 343 { 344 struct tce_container *container; 345 346 if ((arg != VFIO_SPAPR_TCE_IOMMU) && (arg != VFIO_SPAPR_TCE_v2_IOMMU)) { 347 pr_err("tce_vfio: Wrong IOMMU type\n"); 348 return ERR_PTR(-EINVAL); 349 } 350 351 container = kzalloc(sizeof(*container), GFP_KERNEL); 352 if (!container) 353 return ERR_PTR(-ENOMEM); 354 355 mutex_init(&container->lock); 356 INIT_LIST_HEAD_RCU(&container->group_list); 357 INIT_LIST_HEAD_RCU(&container->prereg_list); 358 359 container->v2 = arg == VFIO_SPAPR_TCE_v2_IOMMU; 360 361 return container; 362 } 363 364 static int tce_iommu_clear(struct tce_container *container, 365 struct iommu_table *tbl, 366 unsigned long entry, unsigned long pages); 367 static void tce_iommu_free_table(struct tce_container *container, 368 struct iommu_table *tbl); 369 370 static void tce_iommu_release(void *iommu_data) 371 { 372 struct tce_container *container = iommu_data; 373 struct tce_iommu_group *tcegrp; 374 long i; 375 376 while (tce_groups_attached(container)) { 377 tcegrp = list_first_entry(&container->group_list, 378 struct tce_iommu_group, next); 379 tce_iommu_detach_group(iommu_data, tcegrp->grp); 380 } 381 382 /* 383 * If VFIO created a table, it was not disposed 384 * by tce_iommu_detach_group() so do it now. 385 */ 386 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 387 struct iommu_table *tbl = container->tables[i]; 388 389 if (!tbl) 390 continue; 391 392 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size); 393 tce_iommu_free_table(container, tbl); 394 } 395 396 while (!list_empty(&container->prereg_list)) { 397 struct tce_iommu_prereg *tcemem; 398 399 tcemem = list_first_entry(&container->prereg_list, 400 struct tce_iommu_prereg, next); 401 WARN_ON_ONCE(tce_iommu_prereg_free(container, tcemem)); 402 } 403 404 tce_iommu_disable(container); 405 if (container->mm) 406 mmdrop(container->mm); 407 mutex_destroy(&container->lock); 408 409 kfree(container); 410 } 411 412 static void tce_iommu_unuse_page(struct tce_container *container, 413 unsigned long hpa) 414 { 415 struct page *page; 416 417 page = pfn_to_page(hpa >> PAGE_SHIFT); 418 put_page(page); 419 } 420 421 static int tce_iommu_prereg_ua_to_hpa(struct tce_container *container, 422 unsigned long tce, unsigned long size, 423 unsigned long *phpa, struct mm_iommu_table_group_mem_t **pmem) 424 { 425 long ret = 0; 426 struct mm_iommu_table_group_mem_t *mem; 427 428 mem = mm_iommu_lookup(container->mm, tce, size); 429 if (!mem) 430 return -EINVAL; 431 432 ret = mm_iommu_ua_to_hpa(mem, tce, phpa); 433 if (ret) 434 return -EINVAL; 435 436 *pmem = mem; 437 438 return 0; 439 } 440 441 static void tce_iommu_unuse_page_v2(struct tce_container *container, 442 struct iommu_table *tbl, unsigned long entry) 443 { 444 struct mm_iommu_table_group_mem_t *mem = NULL; 445 int ret; 446 unsigned long hpa = 0; 447 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry); 448 449 if (!pua) 450 return; 451 452 ret = tce_iommu_prereg_ua_to_hpa(container, be64_to_cpu(*pua), 453 IOMMU_PAGE_SIZE(tbl), &hpa, &mem); 454 if (ret) 455 pr_debug("%s: tce %llx at #%lx was not cached, ret=%d\n", 456 __func__, be64_to_cpu(*pua), entry, ret); 457 if (mem) 458 mm_iommu_mapped_dec(mem); 459 460 *pua = cpu_to_be64(0); 461 } 462 463 static int tce_iommu_clear(struct tce_container *container, 464 struct iommu_table *tbl, 465 unsigned long entry, unsigned long pages) 466 { 467 unsigned long oldhpa; 468 long ret; 469 enum dma_data_direction direction; 470 471 for ( ; pages; --pages, ++entry) { 472 cond_resched(); 473 474 direction = DMA_NONE; 475 oldhpa = 0; 476 ret = iommu_tce_xchg(tbl, entry, &oldhpa, &direction); 477 if (ret) 478 continue; 479 480 if (direction == DMA_NONE) 481 continue; 482 483 if (container->v2) { 484 tce_iommu_unuse_page_v2(container, tbl, entry); 485 continue; 486 } 487 488 tce_iommu_unuse_page(container, oldhpa); 489 } 490 491 return 0; 492 } 493 494 static int tce_iommu_use_page(unsigned long tce, unsigned long *hpa) 495 { 496 struct page *page = NULL; 497 enum dma_data_direction direction = iommu_tce_direction(tce); 498 499 if (get_user_pages_fast(tce & PAGE_MASK, 1, 500 direction != DMA_TO_DEVICE, &page) != 1) 501 return -EFAULT; 502 503 *hpa = __pa((unsigned long) page_address(page)); 504 505 return 0; 506 } 507 508 static long tce_iommu_build(struct tce_container *container, 509 struct iommu_table *tbl, 510 unsigned long entry, unsigned long tce, unsigned long pages, 511 enum dma_data_direction direction) 512 { 513 long i, ret = 0; 514 struct page *page; 515 unsigned long hpa; 516 enum dma_data_direction dirtmp; 517 518 for (i = 0; i < pages; ++i) { 519 unsigned long offset = tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK; 520 521 ret = tce_iommu_use_page(tce, &hpa); 522 if (ret) 523 break; 524 525 page = pfn_to_page(hpa >> PAGE_SHIFT); 526 if (!tce_page_is_contained(page, tbl->it_page_shift)) { 527 ret = -EPERM; 528 break; 529 } 530 531 hpa |= offset; 532 dirtmp = direction; 533 ret = iommu_tce_xchg(tbl, entry + i, &hpa, &dirtmp); 534 if (ret) { 535 tce_iommu_unuse_page(container, hpa); 536 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n", 537 __func__, entry << tbl->it_page_shift, 538 tce, ret); 539 break; 540 } 541 542 if (dirtmp != DMA_NONE) 543 tce_iommu_unuse_page(container, hpa); 544 545 tce += IOMMU_PAGE_SIZE(tbl); 546 } 547 548 if (ret) 549 tce_iommu_clear(container, tbl, entry, i); 550 551 return ret; 552 } 553 554 static long tce_iommu_build_v2(struct tce_container *container, 555 struct iommu_table *tbl, 556 unsigned long entry, unsigned long tce, unsigned long pages, 557 enum dma_data_direction direction) 558 { 559 long i, ret = 0; 560 struct page *page; 561 unsigned long hpa; 562 enum dma_data_direction dirtmp; 563 564 for (i = 0; i < pages; ++i) { 565 struct mm_iommu_table_group_mem_t *mem = NULL; 566 __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry + i); 567 568 ret = tce_iommu_prereg_ua_to_hpa(container, 569 tce, IOMMU_PAGE_SIZE(tbl), &hpa, &mem); 570 if (ret) 571 break; 572 573 page = pfn_to_page(hpa >> PAGE_SHIFT); 574 if (!tce_page_is_contained(page, tbl->it_page_shift)) { 575 ret = -EPERM; 576 break; 577 } 578 579 /* Preserve offset within IOMMU page */ 580 hpa |= tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK; 581 dirtmp = direction; 582 583 /* The registered region is being unregistered */ 584 if (mm_iommu_mapped_inc(mem)) 585 break; 586 587 ret = iommu_tce_xchg(tbl, entry + i, &hpa, &dirtmp); 588 if (ret) { 589 /* dirtmp cannot be DMA_NONE here */ 590 tce_iommu_unuse_page_v2(container, tbl, entry + i); 591 pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n", 592 __func__, entry << tbl->it_page_shift, 593 tce, ret); 594 break; 595 } 596 597 if (dirtmp != DMA_NONE) 598 tce_iommu_unuse_page_v2(container, tbl, entry + i); 599 600 *pua = cpu_to_be64(tce); 601 602 tce += IOMMU_PAGE_SIZE(tbl); 603 } 604 605 if (ret) 606 tce_iommu_clear(container, tbl, entry, i); 607 608 return ret; 609 } 610 611 static long tce_iommu_create_table(struct tce_container *container, 612 struct iommu_table_group *table_group, 613 int num, 614 __u32 page_shift, 615 __u64 window_size, 616 __u32 levels, 617 struct iommu_table **ptbl) 618 { 619 long ret, table_size; 620 621 table_size = table_group->ops->get_table_size(page_shift, window_size, 622 levels); 623 if (!table_size) 624 return -EINVAL; 625 626 ret = try_increment_locked_vm(container->mm, table_size >> PAGE_SHIFT); 627 if (ret) 628 return ret; 629 630 ret = table_group->ops->create_table(table_group, num, 631 page_shift, window_size, levels, ptbl); 632 633 WARN_ON(!ret && !(*ptbl)->it_ops->free); 634 WARN_ON(!ret && ((*ptbl)->it_allocated_size != table_size)); 635 636 return ret; 637 } 638 639 static void tce_iommu_free_table(struct tce_container *container, 640 struct iommu_table *tbl) 641 { 642 unsigned long pages = tbl->it_allocated_size >> PAGE_SHIFT; 643 644 iommu_tce_table_put(tbl); 645 decrement_locked_vm(container->mm, pages); 646 } 647 648 static long tce_iommu_create_window(struct tce_container *container, 649 __u32 page_shift, __u64 window_size, __u32 levels, 650 __u64 *start_addr) 651 { 652 struct tce_iommu_group *tcegrp; 653 struct iommu_table_group *table_group; 654 struct iommu_table *tbl = NULL; 655 long ret, num; 656 657 num = tce_iommu_find_free_table(container); 658 if (num < 0) 659 return num; 660 661 /* Get the first group for ops::create_table */ 662 tcegrp = list_first_entry(&container->group_list, 663 struct tce_iommu_group, next); 664 table_group = iommu_group_get_iommudata(tcegrp->grp); 665 if (!table_group) 666 return -EFAULT; 667 668 if (!(table_group->pgsizes & (1ULL << page_shift))) 669 return -EINVAL; 670 671 if (!table_group->ops->set_window || !table_group->ops->unset_window || 672 !table_group->ops->get_table_size || 673 !table_group->ops->create_table) 674 return -EPERM; 675 676 /* Create TCE table */ 677 ret = tce_iommu_create_table(container, table_group, num, 678 page_shift, window_size, levels, &tbl); 679 if (ret) 680 return ret; 681 682 BUG_ON(!tbl->it_ops->free); 683 684 /* 685 * Program the table to every group. 686 * Groups have been tested for compatibility at the attach time. 687 */ 688 list_for_each_entry(tcegrp, &container->group_list, next) { 689 table_group = iommu_group_get_iommudata(tcegrp->grp); 690 691 ret = table_group->ops->set_window(table_group, num, tbl); 692 if (ret) 693 goto unset_exit; 694 } 695 696 container->tables[num] = tbl; 697 698 /* Return start address assigned by platform in create_table() */ 699 *start_addr = tbl->it_offset << tbl->it_page_shift; 700 701 return 0; 702 703 unset_exit: 704 list_for_each_entry(tcegrp, &container->group_list, next) { 705 table_group = iommu_group_get_iommudata(tcegrp->grp); 706 table_group->ops->unset_window(table_group, num); 707 } 708 tce_iommu_free_table(container, tbl); 709 710 return ret; 711 } 712 713 static long tce_iommu_remove_window(struct tce_container *container, 714 __u64 start_addr) 715 { 716 struct iommu_table_group *table_group = NULL; 717 struct iommu_table *tbl; 718 struct tce_iommu_group *tcegrp; 719 int num; 720 721 num = tce_iommu_find_table(container, start_addr, &tbl); 722 if (num < 0) 723 return -EINVAL; 724 725 BUG_ON(!tbl->it_size); 726 727 /* Detach groups from IOMMUs */ 728 list_for_each_entry(tcegrp, &container->group_list, next) { 729 table_group = iommu_group_get_iommudata(tcegrp->grp); 730 731 /* 732 * SPAPR TCE IOMMU exposes the default DMA window to 733 * the guest via dma32_window_start/size of 734 * VFIO_IOMMU_SPAPR_TCE_GET_INFO. Some platforms allow 735 * the userspace to remove this window, some do not so 736 * here we check for the platform capability. 737 */ 738 if (!table_group->ops || !table_group->ops->unset_window) 739 return -EPERM; 740 741 table_group->ops->unset_window(table_group, num); 742 } 743 744 /* Free table */ 745 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size); 746 tce_iommu_free_table(container, tbl); 747 container->tables[num] = NULL; 748 749 return 0; 750 } 751 752 static long tce_iommu_create_default_window(struct tce_container *container) 753 { 754 long ret; 755 __u64 start_addr = 0; 756 struct tce_iommu_group *tcegrp; 757 struct iommu_table_group *table_group; 758 759 if (!container->def_window_pending) 760 return 0; 761 762 if (!tce_groups_attached(container)) 763 return -ENODEV; 764 765 tcegrp = list_first_entry(&container->group_list, 766 struct tce_iommu_group, next); 767 table_group = iommu_group_get_iommudata(tcegrp->grp); 768 if (!table_group) 769 return -ENODEV; 770 771 ret = tce_iommu_create_window(container, IOMMU_PAGE_SHIFT_4K, 772 table_group->tce32_size, 1, &start_addr); 773 WARN_ON_ONCE(!ret && start_addr); 774 775 if (!ret) 776 container->def_window_pending = false; 777 778 return ret; 779 } 780 781 static long tce_iommu_ioctl(void *iommu_data, 782 unsigned int cmd, unsigned long arg) 783 { 784 struct tce_container *container = iommu_data; 785 unsigned long minsz, ddwsz; 786 long ret; 787 788 switch (cmd) { 789 case VFIO_CHECK_EXTENSION: 790 switch (arg) { 791 case VFIO_SPAPR_TCE_IOMMU: 792 case VFIO_SPAPR_TCE_v2_IOMMU: 793 ret = 1; 794 break; 795 default: 796 ret = vfio_spapr_iommu_eeh_ioctl(NULL, cmd, arg); 797 break; 798 } 799 800 return (ret < 0) ? 0 : ret; 801 } 802 803 /* 804 * Sanity check to prevent one userspace from manipulating 805 * another userspace mm. 806 */ 807 BUG_ON(!container); 808 if (container->mm && container->mm != current->mm) 809 return -EPERM; 810 811 switch (cmd) { 812 case VFIO_IOMMU_SPAPR_TCE_GET_INFO: { 813 struct vfio_iommu_spapr_tce_info info; 814 struct tce_iommu_group *tcegrp; 815 struct iommu_table_group *table_group; 816 817 if (!tce_groups_attached(container)) 818 return -ENXIO; 819 820 tcegrp = list_first_entry(&container->group_list, 821 struct tce_iommu_group, next); 822 table_group = iommu_group_get_iommudata(tcegrp->grp); 823 824 if (!table_group) 825 return -ENXIO; 826 827 minsz = offsetofend(struct vfio_iommu_spapr_tce_info, 828 dma32_window_size); 829 830 if (copy_from_user(&info, (void __user *)arg, minsz)) 831 return -EFAULT; 832 833 if (info.argsz < minsz) 834 return -EINVAL; 835 836 info.dma32_window_start = table_group->tce32_start; 837 info.dma32_window_size = table_group->tce32_size; 838 info.flags = 0; 839 memset(&info.ddw, 0, sizeof(info.ddw)); 840 841 if (table_group->max_dynamic_windows_supported && 842 container->v2) { 843 info.flags |= VFIO_IOMMU_SPAPR_INFO_DDW; 844 info.ddw.pgsizes = table_group->pgsizes; 845 info.ddw.max_dynamic_windows_supported = 846 table_group->max_dynamic_windows_supported; 847 info.ddw.levels = table_group->max_levels; 848 } 849 850 ddwsz = offsetofend(struct vfio_iommu_spapr_tce_info, ddw); 851 852 if (info.argsz >= ddwsz) 853 minsz = ddwsz; 854 855 if (copy_to_user((void __user *)arg, &info, minsz)) 856 return -EFAULT; 857 858 return 0; 859 } 860 case VFIO_IOMMU_MAP_DMA: { 861 struct vfio_iommu_type1_dma_map param; 862 struct iommu_table *tbl = NULL; 863 long num; 864 enum dma_data_direction direction; 865 866 if (!container->enabled) 867 return -EPERM; 868 869 minsz = offsetofend(struct vfio_iommu_type1_dma_map, size); 870 871 if (copy_from_user(¶m, (void __user *)arg, minsz)) 872 return -EFAULT; 873 874 if (param.argsz < minsz) 875 return -EINVAL; 876 877 if (param.flags & ~(VFIO_DMA_MAP_FLAG_READ | 878 VFIO_DMA_MAP_FLAG_WRITE)) 879 return -EINVAL; 880 881 ret = tce_iommu_create_default_window(container); 882 if (ret) 883 return ret; 884 885 num = tce_iommu_find_table(container, param.iova, &tbl); 886 if (num < 0) 887 return -ENXIO; 888 889 if ((param.size & ~IOMMU_PAGE_MASK(tbl)) || 890 (param.vaddr & ~IOMMU_PAGE_MASK(tbl))) 891 return -EINVAL; 892 893 /* iova is checked by the IOMMU API */ 894 if (param.flags & VFIO_DMA_MAP_FLAG_READ) { 895 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE) 896 direction = DMA_BIDIRECTIONAL; 897 else 898 direction = DMA_TO_DEVICE; 899 } else { 900 if (param.flags & VFIO_DMA_MAP_FLAG_WRITE) 901 direction = DMA_FROM_DEVICE; 902 else 903 return -EINVAL; 904 } 905 906 ret = iommu_tce_put_param_check(tbl, param.iova, param.vaddr); 907 if (ret) 908 return ret; 909 910 if (container->v2) 911 ret = tce_iommu_build_v2(container, tbl, 912 param.iova >> tbl->it_page_shift, 913 param.vaddr, 914 param.size >> tbl->it_page_shift, 915 direction); 916 else 917 ret = tce_iommu_build(container, tbl, 918 param.iova >> tbl->it_page_shift, 919 param.vaddr, 920 param.size >> tbl->it_page_shift, 921 direction); 922 923 iommu_flush_tce(tbl); 924 925 return ret; 926 } 927 case VFIO_IOMMU_UNMAP_DMA: { 928 struct vfio_iommu_type1_dma_unmap param; 929 struct iommu_table *tbl = NULL; 930 long num; 931 932 if (!container->enabled) 933 return -EPERM; 934 935 minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, 936 size); 937 938 if (copy_from_user(¶m, (void __user *)arg, minsz)) 939 return -EFAULT; 940 941 if (param.argsz < minsz) 942 return -EINVAL; 943 944 /* No flag is supported now */ 945 if (param.flags) 946 return -EINVAL; 947 948 ret = tce_iommu_create_default_window(container); 949 if (ret) 950 return ret; 951 952 num = tce_iommu_find_table(container, param.iova, &tbl); 953 if (num < 0) 954 return -ENXIO; 955 956 if (param.size & ~IOMMU_PAGE_MASK(tbl)) 957 return -EINVAL; 958 959 ret = iommu_tce_clear_param_check(tbl, param.iova, 0, 960 param.size >> tbl->it_page_shift); 961 if (ret) 962 return ret; 963 964 ret = tce_iommu_clear(container, tbl, 965 param.iova >> tbl->it_page_shift, 966 param.size >> tbl->it_page_shift); 967 iommu_flush_tce(tbl); 968 969 return ret; 970 } 971 case VFIO_IOMMU_SPAPR_REGISTER_MEMORY: { 972 struct vfio_iommu_spapr_register_memory param; 973 974 if (!container->v2) 975 break; 976 977 minsz = offsetofend(struct vfio_iommu_spapr_register_memory, 978 size); 979 980 ret = tce_iommu_mm_set(container); 981 if (ret) 982 return ret; 983 984 if (copy_from_user(¶m, (void __user *)arg, minsz)) 985 return -EFAULT; 986 987 if (param.argsz < minsz) 988 return -EINVAL; 989 990 /* No flag is supported now */ 991 if (param.flags) 992 return -EINVAL; 993 994 mutex_lock(&container->lock); 995 ret = tce_iommu_register_pages(container, param.vaddr, 996 param.size); 997 mutex_unlock(&container->lock); 998 999 return ret; 1000 } 1001 case VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY: { 1002 struct vfio_iommu_spapr_register_memory param; 1003 1004 if (!container->v2) 1005 break; 1006 1007 if (!container->mm) 1008 return -EPERM; 1009 1010 minsz = offsetofend(struct vfio_iommu_spapr_register_memory, 1011 size); 1012 1013 if (copy_from_user(¶m, (void __user *)arg, minsz)) 1014 return -EFAULT; 1015 1016 if (param.argsz < minsz) 1017 return -EINVAL; 1018 1019 /* No flag is supported now */ 1020 if (param.flags) 1021 return -EINVAL; 1022 1023 mutex_lock(&container->lock); 1024 ret = tce_iommu_unregister_pages(container, param.vaddr, 1025 param.size); 1026 mutex_unlock(&container->lock); 1027 1028 return ret; 1029 } 1030 case VFIO_IOMMU_ENABLE: 1031 if (container->v2) 1032 break; 1033 1034 mutex_lock(&container->lock); 1035 ret = tce_iommu_enable(container); 1036 mutex_unlock(&container->lock); 1037 return ret; 1038 1039 1040 case VFIO_IOMMU_DISABLE: 1041 if (container->v2) 1042 break; 1043 1044 mutex_lock(&container->lock); 1045 tce_iommu_disable(container); 1046 mutex_unlock(&container->lock); 1047 return 0; 1048 1049 case VFIO_EEH_PE_OP: { 1050 struct tce_iommu_group *tcegrp; 1051 1052 ret = 0; 1053 list_for_each_entry(tcegrp, &container->group_list, next) { 1054 ret = vfio_spapr_iommu_eeh_ioctl(tcegrp->grp, 1055 cmd, arg); 1056 if (ret) 1057 return ret; 1058 } 1059 return ret; 1060 } 1061 1062 case VFIO_IOMMU_SPAPR_TCE_CREATE: { 1063 struct vfio_iommu_spapr_tce_create create; 1064 1065 if (!container->v2) 1066 break; 1067 1068 ret = tce_iommu_mm_set(container); 1069 if (ret) 1070 return ret; 1071 1072 if (!tce_groups_attached(container)) 1073 return -ENXIO; 1074 1075 minsz = offsetofend(struct vfio_iommu_spapr_tce_create, 1076 start_addr); 1077 1078 if (copy_from_user(&create, (void __user *)arg, minsz)) 1079 return -EFAULT; 1080 1081 if (create.argsz < minsz) 1082 return -EINVAL; 1083 1084 if (create.flags) 1085 return -EINVAL; 1086 1087 mutex_lock(&container->lock); 1088 1089 ret = tce_iommu_create_default_window(container); 1090 if (!ret) 1091 ret = tce_iommu_create_window(container, 1092 create.page_shift, 1093 create.window_size, create.levels, 1094 &create.start_addr); 1095 1096 mutex_unlock(&container->lock); 1097 1098 if (!ret && copy_to_user((void __user *)arg, &create, minsz)) 1099 ret = -EFAULT; 1100 1101 return ret; 1102 } 1103 case VFIO_IOMMU_SPAPR_TCE_REMOVE: { 1104 struct vfio_iommu_spapr_tce_remove remove; 1105 1106 if (!container->v2) 1107 break; 1108 1109 ret = tce_iommu_mm_set(container); 1110 if (ret) 1111 return ret; 1112 1113 if (!tce_groups_attached(container)) 1114 return -ENXIO; 1115 1116 minsz = offsetofend(struct vfio_iommu_spapr_tce_remove, 1117 start_addr); 1118 1119 if (copy_from_user(&remove, (void __user *)arg, minsz)) 1120 return -EFAULT; 1121 1122 if (remove.argsz < minsz) 1123 return -EINVAL; 1124 1125 if (remove.flags) 1126 return -EINVAL; 1127 1128 if (container->def_window_pending && !remove.start_addr) { 1129 container->def_window_pending = false; 1130 return 0; 1131 } 1132 1133 mutex_lock(&container->lock); 1134 1135 ret = tce_iommu_remove_window(container, remove.start_addr); 1136 1137 mutex_unlock(&container->lock); 1138 1139 return ret; 1140 } 1141 } 1142 1143 return -ENOTTY; 1144 } 1145 1146 static void tce_iommu_release_ownership(struct tce_container *container, 1147 struct iommu_table_group *table_group) 1148 { 1149 int i; 1150 1151 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 1152 struct iommu_table *tbl = container->tables[i]; 1153 1154 if (!tbl) 1155 continue; 1156 1157 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size); 1158 if (tbl->it_map) 1159 iommu_release_ownership(tbl); 1160 1161 container->tables[i] = NULL; 1162 } 1163 } 1164 1165 static int tce_iommu_take_ownership(struct tce_container *container, 1166 struct iommu_table_group *table_group) 1167 { 1168 int i, j, rc = 0; 1169 1170 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 1171 struct iommu_table *tbl = table_group->tables[i]; 1172 1173 if (!tbl || !tbl->it_map) 1174 continue; 1175 1176 rc = iommu_take_ownership(tbl); 1177 if (rc) { 1178 for (j = 0; j < i; ++j) 1179 iommu_release_ownership( 1180 table_group->tables[j]); 1181 1182 return rc; 1183 } 1184 } 1185 1186 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) 1187 container->tables[i] = table_group->tables[i]; 1188 1189 return 0; 1190 } 1191 1192 static void tce_iommu_release_ownership_ddw(struct tce_container *container, 1193 struct iommu_table_group *table_group) 1194 { 1195 long i; 1196 1197 if (!table_group->ops->unset_window) { 1198 WARN_ON_ONCE(1); 1199 return; 1200 } 1201 1202 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) 1203 table_group->ops->unset_window(table_group, i); 1204 1205 table_group->ops->release_ownership(table_group); 1206 } 1207 1208 static long tce_iommu_take_ownership_ddw(struct tce_container *container, 1209 struct iommu_table_group *table_group) 1210 { 1211 long i, ret = 0; 1212 1213 if (!table_group->ops->create_table || !table_group->ops->set_window || 1214 !table_group->ops->release_ownership) { 1215 WARN_ON_ONCE(1); 1216 return -EFAULT; 1217 } 1218 1219 table_group->ops->take_ownership(table_group); 1220 1221 /* Set all windows to the new group */ 1222 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { 1223 struct iommu_table *tbl = container->tables[i]; 1224 1225 if (!tbl) 1226 continue; 1227 1228 ret = table_group->ops->set_window(table_group, i, tbl); 1229 if (ret) 1230 goto release_exit; 1231 } 1232 1233 return 0; 1234 1235 release_exit: 1236 for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) 1237 table_group->ops->unset_window(table_group, i); 1238 1239 table_group->ops->release_ownership(table_group); 1240 1241 return ret; 1242 } 1243 1244 static int tce_iommu_attach_group(void *iommu_data, 1245 struct iommu_group *iommu_group) 1246 { 1247 int ret; 1248 struct tce_container *container = iommu_data; 1249 struct iommu_table_group *table_group; 1250 struct tce_iommu_group *tcegrp = NULL; 1251 1252 mutex_lock(&container->lock); 1253 1254 /* pr_debug("tce_vfio: Attaching group #%u to iommu %p\n", 1255 iommu_group_id(iommu_group), iommu_group); */ 1256 table_group = iommu_group_get_iommudata(iommu_group); 1257 if (!table_group) { 1258 ret = -ENODEV; 1259 goto unlock_exit; 1260 } 1261 1262 if (tce_groups_attached(container) && (!table_group->ops || 1263 !table_group->ops->take_ownership || 1264 !table_group->ops->release_ownership)) { 1265 ret = -EBUSY; 1266 goto unlock_exit; 1267 } 1268 1269 /* Check if new group has the same iommu_ops (i.e. compatible) */ 1270 list_for_each_entry(tcegrp, &container->group_list, next) { 1271 struct iommu_table_group *table_group_tmp; 1272 1273 if (tcegrp->grp == iommu_group) { 1274 pr_warn("tce_vfio: Group %d is already attached\n", 1275 iommu_group_id(iommu_group)); 1276 ret = -EBUSY; 1277 goto unlock_exit; 1278 } 1279 table_group_tmp = iommu_group_get_iommudata(tcegrp->grp); 1280 if (table_group_tmp->ops->create_table != 1281 table_group->ops->create_table) { 1282 pr_warn("tce_vfio: Group %d is incompatible with group %d\n", 1283 iommu_group_id(iommu_group), 1284 iommu_group_id(tcegrp->grp)); 1285 ret = -EPERM; 1286 goto unlock_exit; 1287 } 1288 } 1289 1290 tcegrp = kzalloc(sizeof(*tcegrp), GFP_KERNEL); 1291 if (!tcegrp) { 1292 ret = -ENOMEM; 1293 goto unlock_exit; 1294 } 1295 1296 if (!table_group->ops || !table_group->ops->take_ownership || 1297 !table_group->ops->release_ownership) { 1298 if (container->v2) { 1299 ret = -EPERM; 1300 goto unlock_exit; 1301 } 1302 ret = tce_iommu_take_ownership(container, table_group); 1303 } else { 1304 if (!container->v2) { 1305 ret = -EPERM; 1306 goto unlock_exit; 1307 } 1308 ret = tce_iommu_take_ownership_ddw(container, table_group); 1309 if (!tce_groups_attached(container) && !container->tables[0]) 1310 container->def_window_pending = true; 1311 } 1312 1313 if (!ret) { 1314 tcegrp->grp = iommu_group; 1315 list_add(&tcegrp->next, &container->group_list); 1316 } 1317 1318 unlock_exit: 1319 if (ret && tcegrp) 1320 kfree(tcegrp); 1321 1322 mutex_unlock(&container->lock); 1323 1324 return ret; 1325 } 1326 1327 static void tce_iommu_detach_group(void *iommu_data, 1328 struct iommu_group *iommu_group) 1329 { 1330 struct tce_container *container = iommu_data; 1331 struct iommu_table_group *table_group; 1332 bool found = false; 1333 struct tce_iommu_group *tcegrp; 1334 1335 mutex_lock(&container->lock); 1336 1337 list_for_each_entry(tcegrp, &container->group_list, next) { 1338 if (tcegrp->grp == iommu_group) { 1339 found = true; 1340 break; 1341 } 1342 } 1343 1344 if (!found) { 1345 pr_warn("tce_vfio: detaching unattached group #%u\n", 1346 iommu_group_id(iommu_group)); 1347 goto unlock_exit; 1348 } 1349 1350 list_del(&tcegrp->next); 1351 kfree(tcegrp); 1352 1353 table_group = iommu_group_get_iommudata(iommu_group); 1354 BUG_ON(!table_group); 1355 1356 if (!table_group->ops || !table_group->ops->release_ownership) 1357 tce_iommu_release_ownership(container, table_group); 1358 else 1359 tce_iommu_release_ownership_ddw(container, table_group); 1360 1361 unlock_exit: 1362 mutex_unlock(&container->lock); 1363 } 1364 1365 const struct vfio_iommu_driver_ops tce_iommu_driver_ops = { 1366 .name = "iommu-vfio-powerpc", 1367 .owner = THIS_MODULE, 1368 .open = tce_iommu_open, 1369 .release = tce_iommu_release, 1370 .ioctl = tce_iommu_ioctl, 1371 .attach_group = tce_iommu_attach_group, 1372 .detach_group = tce_iommu_detach_group, 1373 }; 1374 1375 static int __init tce_iommu_init(void) 1376 { 1377 return vfio_register_iommu_driver(&tce_iommu_driver_ops); 1378 } 1379 1380 static void __exit tce_iommu_cleanup(void) 1381 { 1382 vfio_unregister_iommu_driver(&tce_iommu_driver_ops); 1383 } 1384 1385 module_init(tce_iommu_init); 1386 module_exit(tce_iommu_cleanup); 1387 1388 MODULE_VERSION(DRIVER_VERSION); 1389 MODULE_LICENSE("GPL v2"); 1390 MODULE_AUTHOR(DRIVER_AUTHOR); 1391 MODULE_DESCRIPTION(DRIVER_DESC); 1392 1393