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