drivers/vfio/vfio_iommu_spapr_tce.c

   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 <asm/iommu.h>
  23 #include <asm/tce.h>
  24
  25 #define DRIVER_VERSION  "0.1"
  26 #define DRIVER_AUTHOR   "aik@ozlabs.ru"
  27 #define DRIVER_DESC     "VFIO IOMMU SPAPR TCE"
  28
  29 static void tce_iommu_detach_group(void *iommu_data,
  30                 struct iommu_group *iommu_group);
  31
  32 static long try_increment_locked_vm(long npages)
  33 {
  34         long ret = 0, locked, lock_limit;
  35
  36         if (!current || !current->mm)
  37                 return -ESRCH; /* process exited */
  38
  39         if (!npages)
  40                 return 0;
  41
  42         down_write(&current->mm->mmap_sem);
  43         locked = current->mm->locked_vm + npages;
  44         lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
  45         if (locked > lock_limit && !capable(CAP_IPC_LOCK))
  46                 ret = -ENOMEM;
  47         else
  48                 current->mm->locked_vm += npages;
  49
  50         pr_debug("[%d] RLIMIT_MEMLOCK +%ld %ld/%ld%s\n", current->pid,
  51                         npages << PAGE_SHIFT,
  52                         current->mm->locked_vm << PAGE_SHIFT,
  53                         rlimit(RLIMIT_MEMLOCK),
  54                         ret ? " - exceeded" : "");
  55
  56         up_write(&current->mm->mmap_sem);
  57
  58         return ret;
  59 }
  60
  61 static void decrement_locked_vm(long npages)
  62 {
  63         if (!current || !current->mm || !npages)
  64                 return; /* process exited */
  65
  66         down_write(&current->mm->mmap_sem);
  67         if (WARN_ON_ONCE(npages > current->mm->locked_vm))
  68                 npages = current->mm->locked_vm;
  69         current->mm->locked_vm -= npages;
  70         pr_debug("[%d] RLIMIT_MEMLOCK -%ld %ld/%ld\n", current->pid,
  71                         npages << PAGE_SHIFT,
  72                         current->mm->locked_vm << PAGE_SHIFT,
  73                         rlimit(RLIMIT_MEMLOCK));
  74         up_write(&current->mm->mmap_sem);
  75 }
  76
  77 /*
  78  * VFIO IOMMU fd for SPAPR_TCE IOMMU implementation
  79  *
  80  * This code handles mapping and unmapping of user data buffers
  81  * into DMA'ble space using the IOMMU
  82  */
  83
  84 /*
  85  * The container descriptor supports only a single group per container.
  86  * Required by the API as the container is not supplied with the IOMMU group
  87  * at the moment of initialization.
  88  */
  89 struct tce_container {
  90         struct mutex lock;
  91         struct iommu_group *grp;
  92         bool enabled;
  93         unsigned long locked_pages;
  94 };
  95
  96 static bool tce_page_is_contained(struct page *page, unsigned page_shift)
  97 {
  98         /*
  99          * Check that the TCE table granularity is not bigger than the size of
 100          * a page we just found. Otherwise the hardware can get access to
 101          * a bigger memory chunk that it should.
 102          */
 103         return (PAGE_SHIFT + compound_order(compound_head(page))) >= page_shift;
 104 }
 105
 106 static long tce_iommu_find_table(struct tce_container *container,
 107                 phys_addr_t ioba, struct iommu_table **ptbl)
 108 {
 109         long i;
 110         struct iommu_table_group *table_group;
 111
 112         table_group = iommu_group_get_iommudata(container->grp);
 113         if (!table_group)
 114                 return -1;
 115
 116         for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
 117                 struct iommu_table *tbl = table_group->tables[i];
 118
 119                 if (tbl) {
 120                         unsigned long entry = ioba >> tbl->it_page_shift;
 121                         unsigned long start = tbl->it_offset;
 122                         unsigned long end = start + tbl->it_size;
 123
 124                         if ((start <= entry) && (entry < end)) {
 125                                 *ptbl = tbl;
 126                                 return i;
 127                         }
 128                 }
 129         }
 130
 131         return -1;
 132 }
 133
 134 static int tce_iommu_enable(struct tce_container *container)
 135 {
 136         int ret = 0;
 137         unsigned long locked;
 138         struct iommu_table_group *table_group;
 139
 140         if (!container->grp)
 141                 return -ENXIO;
 142
 143         if (!current->mm)
 144                 return -ESRCH; /* process exited */
 145
 146         if (container->enabled)
 147                 return -EBUSY;
 148
 149         /*
 150          * When userspace pages are mapped into the IOMMU, they are effectively
 151          * locked memory, so, theoretically, we need to update the accounting
 152          * of locked pages on each map and unmap.  For powerpc, the map unmap
 153          * paths can be very hot, though, and the accounting would kill
 154          * performance, especially since it would be difficult to impossible
 155          * to handle the accounting in real mode only.
 156          *
 157          * To address that, rather than precisely accounting every page, we
 158          * instead account for a worst case on locked memory when the iommu is
 159          * enabled and disabled.  The worst case upper bound on locked memory
 160          * is the size of the whole iommu window, which is usually relatively
 161          * small (compared to total memory sizes) on POWER hardware.
 162          *
 163          * Also we don't have a nice way to fail on H_PUT_TCE due to ulimits,
 164          * that would effectively kill the guest at random points, much better
 165          * enforcing the limit based on the max that the guest can map.
 166          *
 167          * Unfortunately at the moment it counts whole tables, no matter how
 168          * much memory the guest has. I.e. for 4GB guest and 4 IOMMU groups
 169          * each with 2GB DMA window, 8GB will be counted here. The reason for
 170          * this is that we cannot tell here the amount of RAM used by the guest
 171          * as this information is only available from KVM and VFIO is
 172          * KVM agnostic.
 173          *
 174          * So we do not allow enabling a container without a group attached
 175          * as there is no way to know how much we should increment
 176          * the locked_vm counter.
 177          */
 178         table_group = iommu_group_get_iommudata(container->grp);
 179         if (!table_group)
 180                 return -ENODEV;
 181
 182         if (!table_group->tce32_size)
 183                 return -EPERM;
 184
 185         locked = table_group->tce32_size >> PAGE_SHIFT;
 186         ret = try_increment_locked_vm(locked);
 187         if (ret)
 188                 return ret;
 189
 190         container->locked_pages = locked;
 191
 192         container->enabled = true;
 193
 194         return ret;
 195 }
 196
 197 static void tce_iommu_disable(struct tce_container *container)
 198 {
 199         if (!container->enabled)
 200                 return;
 201
 202         container->enabled = false;
 203
 204         if (!current->mm)
 205                 return;
 206
 207         decrement_locked_vm(container->locked_pages);
 208 }
 209
 210 static void *tce_iommu_open(unsigned long arg)
 211 {
 212         struct tce_container *container;
 213
 214         if (arg != VFIO_SPAPR_TCE_IOMMU) {
 215                 pr_err("tce_vfio: Wrong IOMMU type\n");
 216                 return ERR_PTR(-EINVAL);
 217         }
 218
 219         container = kzalloc(sizeof(*container), GFP_KERNEL);
 220         if (!container)
 221                 return ERR_PTR(-ENOMEM);
 222
 223         mutex_init(&container->lock);
 224
 225         return container;
 226 }
 227
 228 static void tce_iommu_release(void *iommu_data)
 229 {
 230         struct tce_container *container = iommu_data;
 231
 232         WARN_ON(container->grp);
 233
 234         if (container->grp)
 235                 tce_iommu_detach_group(iommu_data, container->grp);
 236
 237         tce_iommu_disable(container);
 238         mutex_destroy(&container->lock);
 239
 240         kfree(container);
 241 }
 242
 243 static void tce_iommu_unuse_page(struct tce_container *container,
 244                 unsigned long hpa)
 245 {
 246         struct page *page;
 247
 248         page = pfn_to_page(hpa >> PAGE_SHIFT);
 249         put_page(page);
 250 }
 251
 252 static int tce_iommu_clear(struct tce_container *container,
 253                 struct iommu_table *tbl,
 254                 unsigned long entry, unsigned long pages)
 255 {
 256         unsigned long oldhpa;
 257         long ret;
 258         enum dma_data_direction direction;
 259
 260         for ( ; pages; --pages, ++entry) {
 261                 direction = DMA_NONE;
 262                 oldhpa = 0;
 263                 ret = iommu_tce_xchg(tbl, entry, &oldhpa, &direction);
 264                 if (ret)
 265                         continue;
 266
 267                 if (direction == DMA_NONE)
 268                         continue;
 269
 270                 tce_iommu_unuse_page(container, oldhpa);
 271         }
 272
 273         return 0;
 274 }
 275
 276 static int tce_iommu_use_page(unsigned long tce, unsigned long *hpa)
 277 {
 278         struct page *page = NULL;
 279         enum dma_data_direction direction = iommu_tce_direction(tce);
 280
 281         if (get_user_pages_fast(tce & PAGE_MASK, 1,
 282                         direction != DMA_TO_DEVICE, &page) != 1)
 283                 return -EFAULT;
 284
 285         *hpa = __pa((unsigned long) page_address(page));
 286
 287         return 0;
 288 }
 289
 290 static long tce_iommu_build(struct tce_container *container,
 291                 struct iommu_table *tbl,
 292                 unsigned long entry, unsigned long tce, unsigned long pages,
 293                 enum dma_data_direction direction)
 294 {
 295         long i, ret = 0;
 296         struct page *page;
 297         unsigned long hpa;
 298         enum dma_data_direction dirtmp;
 299
 300         for (i = 0; i < pages; ++i) {
 301                 unsigned long offset = tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
 302
 303                 ret = tce_iommu_use_page(tce, &hpa);
 304                 if (ret)
 305                         break;
 306
 307                 page = pfn_to_page(hpa >> PAGE_SHIFT);
 308                 if (!tce_page_is_contained(page, tbl->it_page_shift)) {
 309                         ret = -EPERM;
 310                         break;
 311                 }
 312
 313                 hpa |= offset;
 314                 dirtmp = direction;
 315                 ret = iommu_tce_xchg(tbl, entry + i, &hpa, &dirtmp);
 316                 if (ret) {
 317                         tce_iommu_unuse_page(container, hpa);
 318                         pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n",
 319                                         __func__, entry << tbl->it_page_shift,
 320                                         tce, ret);
 321                         break;
 322                 }
 323
 324                 if (dirtmp != DMA_NONE)
 325                         tce_iommu_unuse_page(container, hpa);
 326
 327                 tce += IOMMU_PAGE_SIZE(tbl);
 328         }
 329
 330         if (ret)
 331                 tce_iommu_clear(container, tbl, entry, i);
 332
 333         return ret;
 334 }
 335
 336 static long tce_iommu_create_table(struct tce_container *container,
 337                         struct iommu_table_group *table_group,
 338                         int num,
 339                         __u32 page_shift,
 340                         __u64 window_size,
 341                         __u32 levels,
 342                         struct iommu_table **ptbl)
 343 {
 344         long ret, table_size;
 345
 346         table_size = table_group->ops->get_table_size(page_shift, window_size,
 347                         levels);
 348         if (!table_size)
 349                 return -EINVAL;
 350
 351         ret = try_increment_locked_vm(table_size >> PAGE_SHIFT);
 352         if (ret)
 353                 return ret;
 354
 355         ret = table_group->ops->create_table(table_group, num,
 356                         page_shift, window_size, levels, ptbl);
 357
 358         WARN_ON(!ret && !(*ptbl)->it_ops->free);
 359         WARN_ON(!ret && ((*ptbl)->it_allocated_size != table_size));
 360
 361         if (ret)
 362                 decrement_locked_vm(table_size >> PAGE_SHIFT);
 363
 364         return ret;
 365 }
 366
 367 static void tce_iommu_free_table(struct iommu_table *tbl)
 368 {
 369         unsigned long pages = tbl->it_allocated_size >> PAGE_SHIFT;
 370
 371         tbl->it_ops->free(tbl);
 372         decrement_locked_vm(pages);
 373 }
 374
 375 static long tce_iommu_ioctl(void *iommu_data,
 376                                  unsigned int cmd, unsigned long arg)
 377 {
 378         struct tce_container *container = iommu_data;
 379         unsigned long minsz;
 380         long ret;
 381
 382         switch (cmd) {
 383         case VFIO_CHECK_EXTENSION:
 384                 switch (arg) {
 385                 case VFIO_SPAPR_TCE_IOMMU:
 386                         ret = 1;
 387                         break;
 388                 default:
 389                         ret = vfio_spapr_iommu_eeh_ioctl(NULL, cmd, arg);
 390                         break;
 391                 }
 392
 393                 return (ret < 0) ? 0 : ret;
 394
 395         case VFIO_IOMMU_SPAPR_TCE_GET_INFO: {
 396                 struct vfio_iommu_spapr_tce_info info;
 397                 struct iommu_table_group *table_group;
 398
 399                 if (WARN_ON(!container->grp))
 400                         return -ENXIO;
 401
 402                 table_group = iommu_group_get_iommudata(container->grp);
 403
 404                 if (!table_group)
 405                         return -ENXIO;
 406
 407                 minsz = offsetofend(struct vfio_iommu_spapr_tce_info,
 408                                 dma32_window_size);
 409
 410                 if (copy_from_user(&info, (void __user *)arg, minsz))
 411                         return -EFAULT;
 412
 413                 if (info.argsz < minsz)
 414                         return -EINVAL;
 415
 416                 info.dma32_window_start = table_group->tce32_start;
 417                 info.dma32_window_size = table_group->tce32_size;
 418                 info.flags = 0;
 419
 420                 if (copy_to_user((void __user *)arg, &info, minsz))
 421                         return -EFAULT;
 422
 423                 return 0;
 424         }
 425         case VFIO_IOMMU_MAP_DMA: {
 426                 struct vfio_iommu_type1_dma_map param;
 427                 struct iommu_table *tbl = NULL;
 428                 long num;
 429                 enum dma_data_direction direction;
 430
 431                 if (!container->enabled)
 432                         return -EPERM;
 433
 434                 minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
 435
 436                 if (copy_from_user(&param, (void __user *)arg, minsz))
 437                         return -EFAULT;
 438
 439                 if (param.argsz < minsz)
 440                         return -EINVAL;
 441
 442                 if (param.flags & ~(VFIO_DMA_MAP_FLAG_READ |
 443                                 VFIO_DMA_MAP_FLAG_WRITE))
 444                         return -EINVAL;
 445
 446                 num = tce_iommu_find_table(container, param.iova, &tbl);
 447                 if (num < 0)
 448                         return -ENXIO;
 449
 450                 if ((param.size & ~IOMMU_PAGE_MASK(tbl)) ||
 451                                 (param.vaddr & ~IOMMU_PAGE_MASK(tbl)))
 452                         return -EINVAL;
 453
 454                 /* iova is checked by the IOMMU API */
 455                 if (param.flags & VFIO_DMA_MAP_FLAG_READ) {
 456                         if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
 457                                 direction = DMA_BIDIRECTIONAL;
 458                         else
 459                                 direction = DMA_TO_DEVICE;
 460                 } else {
 461                         if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
 462                                 direction = DMA_FROM_DEVICE;
 463                         else
 464                                 return -EINVAL;
 465                 }
 466
 467                 ret = iommu_tce_put_param_check(tbl, param.iova, param.vaddr);
 468                 if (ret)
 469                         return ret;
 470
 471                 ret = tce_iommu_build(container, tbl,
 472                                 param.iova >> tbl->it_page_shift,
 473                                 param.vaddr,
 474                                 param.size >> tbl->it_page_shift,
 475                                 direction);
 476
 477                 iommu_flush_tce(tbl);
 478
 479                 return ret;
 480         }
 481         case VFIO_IOMMU_UNMAP_DMA: {
 482                 struct vfio_iommu_type1_dma_unmap param;
 483                 struct iommu_table *tbl = NULL;
 484                 long num;
 485
 486                 if (!container->enabled)
 487                         return -EPERM;
 488
 489                 minsz = offsetofend(struct vfio_iommu_type1_dma_unmap,
 490                                 size);
 491
 492                 if (copy_from_user(&param, (void __user *)arg, minsz))
 493                         return -EFAULT;
 494
 495                 if (param.argsz < minsz)
 496                         return -EINVAL;
 497
 498                 /* No flag is supported now */
 499                 if (param.flags)
 500                         return -EINVAL;
 501
 502                 num = tce_iommu_find_table(container, param.iova, &tbl);
 503                 if (num < 0)
 504                         return -ENXIO;
 505
 506                 if (param.size & ~IOMMU_PAGE_MASK(tbl))
 507                         return -EINVAL;
 508
 509                 ret = iommu_tce_clear_param_check(tbl, param.iova, 0,
 510                                 param.size >> tbl->it_page_shift);
 511                 if (ret)
 512                         return ret;
 513
 514                 ret = tce_iommu_clear(container, tbl,
 515                                 param.iova >> tbl->it_page_shift,
 516                                 param.size >> tbl->it_page_shift);
 517                 iommu_flush_tce(tbl);
 518
 519                 return ret;
 520         }
 521         case VFIO_IOMMU_ENABLE:
 522                 mutex_lock(&container->lock);
 523                 ret = tce_iommu_enable(container);
 524                 mutex_unlock(&container->lock);
 525                 return ret;
 526
 527
 528         case VFIO_IOMMU_DISABLE:
 529                 mutex_lock(&container->lock);
 530                 tce_iommu_disable(container);
 531                 mutex_unlock(&container->lock);
 532                 return 0;
 533         case VFIO_EEH_PE_OP:
 534                 if (!container->grp)
 535                         return -ENODEV;
 536
 537                 return vfio_spapr_iommu_eeh_ioctl(container->grp,
 538                                                   cmd, arg);
 539         }
 540
 541         return -ENOTTY;
 542 }
 543
 544 static void tce_iommu_release_ownership(struct tce_container *container,
 545                 struct iommu_table_group *table_group)
 546 {
 547         int i;
 548
 549         for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
 550                 struct iommu_table *tbl = table_group->tables[i];
 551
 552                 if (!tbl)
 553                         continue;
 554
 555                 tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
 556                 if (tbl->it_map)
 557                         iommu_release_ownership(tbl);
 558         }
 559 }
 560
 561 static int tce_iommu_take_ownership(struct tce_container *container,
 562                 struct iommu_table_group *table_group)
 563 {
 564         int i, j, rc = 0;
 565
 566         for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
 567                 struct iommu_table *tbl = table_group->tables[i];
 568
 569                 if (!tbl || !tbl->it_map)
 570                         continue;
 571
 572                 rc = iommu_take_ownership(tbl);
 573                 if (rc) {
 574                         for (j = 0; j < i; ++j)
 575                                 iommu_release_ownership(
 576                                                 table_group->tables[j]);
 577
 578                         return rc;
 579                 }
 580         }
 581
 582         return 0;
 583 }
 584
 585 static void tce_iommu_release_ownership_ddw(struct tce_container *container,
 586                 struct iommu_table_group *table_group)
 587 {
 588         long i;
 589
 590         if (!table_group->ops->unset_window) {
 591                 WARN_ON_ONCE(1);
 592                 return;
 593         }
 594
 595         for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
 596                 /* Store table pointer as unset_window resets it */
 597                 struct iommu_table *tbl = table_group->tables[i];
 598
 599                 if (!tbl)
 600                         continue;
 601
 602                 table_group->ops->unset_window(table_group, i);
 603                 tce_iommu_clear(container, tbl,
 604                                 tbl->it_offset, tbl->it_size);
 605                 tce_iommu_free_table(tbl);
 606         }
 607
 608         table_group->ops->release_ownership(table_group);
 609 }
 610
 611 static long tce_iommu_take_ownership_ddw(struct tce_container *container,
 612                 struct iommu_table_group *table_group)
 613 {
 614         long ret;
 615         struct iommu_table *tbl = NULL;
 616
 617         if (!table_group->ops->create_table || !table_group->ops->set_window ||
 618                         !table_group->ops->release_ownership) {
 619                 WARN_ON_ONCE(1);
 620                 return -EFAULT;
 621         }
 622
 623         table_group->ops->take_ownership(table_group);
 624
 625         ret = tce_iommu_create_table(container,
 626                         table_group,
 627                         0, /* window number */
 628                         IOMMU_PAGE_SHIFT_4K,
 629                         table_group->tce32_size,
 630                         1, /* default levels */
 631                         &tbl);
 632         if (!ret) {
 633                 ret = table_group->ops->set_window(table_group, 0, tbl);
 634                 if (ret)
 635                         tce_iommu_free_table(tbl);
 636                 else
 637                         table_group->tables[0] = tbl;
 638         }
 639
 640         if (ret)
 641                 table_group->ops->release_ownership(table_group);
 642
 643         return ret;
 644 }
 645
 646 static int tce_iommu_attach_group(void *iommu_data,
 647                 struct iommu_group *iommu_group)
 648 {
 649         int ret;
 650         struct tce_container *container = iommu_data;
 651         struct iommu_table_group *table_group;
 652
 653         mutex_lock(&container->lock);
 654
 655         /* pr_debug("tce_vfio: Attaching group #%u to iommu %p\n",
 656                         iommu_group_id(iommu_group), iommu_group); */
 657         if (container->grp) {
 658                 pr_warn("tce_vfio: Only one group per IOMMU container is allowed, existing id=%d, attaching id=%d\n",
 659                                 iommu_group_id(container->grp),
 660                                 iommu_group_id(iommu_group));
 661                 ret = -EBUSY;
 662                 goto unlock_exit;
 663         }
 664
 665         if (container->enabled) {
 666                 pr_err("tce_vfio: attaching group #%u to enabled container\n",
 667                                 iommu_group_id(iommu_group));
 668                 ret = -EBUSY;
 669                 goto unlock_exit;
 670         }
 671
 672         table_group = iommu_group_get_iommudata(iommu_group);
 673         if (!table_group) {
 674                 ret = -ENXIO;
 675                 goto unlock_exit;
 676         }
 677
 678         if (!table_group->ops || !table_group->ops->take_ownership ||
 679                         !table_group->ops->release_ownership)
 680                 ret = tce_iommu_take_ownership(container, table_group);
 681         else
 682                 ret = tce_iommu_take_ownership_ddw(container, table_group);
 683
 684         if (!ret)
 685                 container->grp = iommu_group;
 686
 687 unlock_exit:
 688         mutex_unlock(&container->lock);
 689
 690         return ret;
 691 }
 692
 693 static void tce_iommu_detach_group(void *iommu_data,
 694                 struct iommu_group *iommu_group)
 695 {
 696         struct tce_container *container = iommu_data;
 697         struct iommu_table_group *table_group;
 698
 699         mutex_lock(&container->lock);
 700         if (iommu_group != container->grp) {
 701                 pr_warn("tce_vfio: detaching group #%u, expected group is #%u\n",
 702                                 iommu_group_id(iommu_group),
 703                                 iommu_group_id(container->grp));
 704                 goto unlock_exit;
 705         }
 706
 707         if (container->enabled) {
 708                 pr_warn("tce_vfio: detaching group #%u from enabled container, forcing disable\n",
 709                                 iommu_group_id(container->grp));
 710                 tce_iommu_disable(container);
 711         }
 712
 713         /* pr_debug("tce_vfio: detaching group #%u from iommu %p\n",
 714            iommu_group_id(iommu_group), iommu_group); */
 715         container->grp = NULL;
 716
 717         table_group = iommu_group_get_iommudata(iommu_group);
 718         BUG_ON(!table_group);
 719
 720         if (!table_group->ops || !table_group->ops->release_ownership)
 721                 tce_iommu_release_ownership(container, table_group);
 722         else
 723                 tce_iommu_release_ownership_ddw(container, table_group);
 724
 725 unlock_exit:
 726         mutex_unlock(&container->lock);
 727 }
 728
 729 const struct vfio_iommu_driver_ops tce_iommu_driver_ops = {
 730         .name           = "iommu-vfio-powerpc",
 731         .owner          = THIS_MODULE,
 732         .open           = tce_iommu_open,
 733         .release        = tce_iommu_release,
 734         .ioctl          = tce_iommu_ioctl,
 735         .attach_group   = tce_iommu_attach_group,
 736         .detach_group   = tce_iommu_detach_group,
 737 };
 738
 739 static int __init tce_iommu_init(void)
 740 {
 741         return vfio_register_iommu_driver(&tce_iommu_driver_ops);
 742 }
 743
 744 static void __exit tce_iommu_cleanup(void)
 745 {
 746         vfio_unregister_iommu_driver(&tce_iommu_driver_ops);
 747 }
 748
 749 module_init(tce_iommu_init);
 750 module_exit(tce_iommu_cleanup);
 751
 752 MODULE_VERSION(DRIVER_VERSION);
 753 MODULE_LICENSE("GPL v2");
 754 MODULE_AUTHOR(DRIVER_AUTHOR);
 755 MODULE_DESCRIPTION(DRIVER_DESC);
 756