drivers/gpu/drm/i915/i915_gem.c

   1 /*
   2  * Copyright © 2008-2015 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  *
  26  */
  27
  28 #include <drm/drmP.h>
  29 #include <drm/drm_vma_manager.h>
  30 #include <drm/i915_drm.h>
  31 #include "i915_drv.h"
  32 #include "i915_vgpu.h"
  33 #include "i915_trace.h"
  34 #include "intel_drv.h"
  35 #include "intel_mocs.h"
  36 #include <linux/shmem_fs.h>
  37 #include <linux/slab.h>
  38 #include <linux/swap.h>
  39 #include <linux/pci.h>
  40 #include <linux/dma-buf.h>
  41
  42 static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj);
  43 static void i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj);
  44 static void
  45 i915_gem_object_retire__write(struct drm_i915_gem_object *obj);
  46 static void
  47 i915_gem_object_retire__read(struct drm_i915_gem_object *obj, int ring);
  48
  49 static bool cpu_cache_is_coherent(struct drm_device *dev,
  50                                   enum i915_cache_level level)
  51 {
  52         return HAS_LLC(dev) || level != I915_CACHE_NONE;
  53 }
  54
  55 static bool cpu_write_needs_clflush(struct drm_i915_gem_object *obj)
  56 {
  57         if (obj->base.write_domain == I915_GEM_DOMAIN_CPU)
  58                 return false;
  59
  60         if (!cpu_cache_is_coherent(obj->base.dev, obj->cache_level))
  61                 return true;
  62
  63         return obj->pin_display;
  64 }
  65
  66 static int
  67 insert_mappable_node(struct drm_i915_private *i915,
  68                      struct drm_mm_node *node, u32 size)
  69 {
  70         memset(node, 0, sizeof(*node));
  71         return drm_mm_insert_node_in_range_generic(&i915->ggtt.base.mm, node,
  72                                                    size, 0, 0, 0,
  73                                                    i915->ggtt.mappable_end,
  74                                                    DRM_MM_SEARCH_DEFAULT,
  75                                                    DRM_MM_CREATE_DEFAULT);
  76 }
  77
  78 static void
  79 remove_mappable_node(struct drm_mm_node *node)
  80 {
  81         drm_mm_remove_node(node);
  82 }
  83
  84 /* some bookkeeping */
  85 static void i915_gem_info_add_obj(struct drm_i915_private *dev_priv,
  86                                   size_t size)
  87 {
  88         spin_lock(&dev_priv->mm.object_stat_lock);
  89         dev_priv->mm.object_count++;
  90         dev_priv->mm.object_memory += size;
  91         spin_unlock(&dev_priv->mm.object_stat_lock);
  92 }
  93
  94 static void i915_gem_info_remove_obj(struct drm_i915_private *dev_priv,
  95                                      size_t size)
  96 {
  97         spin_lock(&dev_priv->mm.object_stat_lock);
  98         dev_priv->mm.object_count--;
  99         dev_priv->mm.object_memory -= size;
 100         spin_unlock(&dev_priv->mm.object_stat_lock);
 101 }
 102
 103 static int
 104 i915_gem_wait_for_error(struct i915_gpu_error *error)
 105 {
 106         int ret;
 107
 108         if (!i915_reset_in_progress(error))
 109                 return 0;
 110
 111         /*
 112          * Only wait 10 seconds for the gpu reset to complete to avoid hanging
 113          * userspace. If it takes that long something really bad is going on and
 114          * we should simply try to bail out and fail as gracefully as possible.
 115          */
 116         ret = wait_event_interruptible_timeout(error->reset_queue,
 117                                                !i915_reset_in_progress(error),
 118                                                10*HZ);
 119         if (ret == 0) {
 120                 DRM_ERROR("Timed out waiting for the gpu reset to complete\n");
 121                 return -EIO;
 122         } else if (ret < 0) {
 123                 return ret;
 124         } else {
 125                 return 0;
 126         }
 127 }
 128
 129 int i915_mutex_lock_interruptible(struct drm_device *dev)
 130 {
 131         struct drm_i915_private *dev_priv = to_i915(dev);
 132         int ret;
 133
 134         ret = i915_gem_wait_for_error(&dev_priv->gpu_error);
 135         if (ret)
 136                 return ret;
 137
 138         ret = mutex_lock_interruptible(&dev->struct_mutex);
 139         if (ret)
 140                 return ret;
 141
 142         WARN_ON(i915_verify_lists(dev));
 143         return 0;
 144 }
 145
 146 int
 147 i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data,
 148                             struct drm_file *file)
 149 {
 150         struct drm_i915_private *dev_priv = to_i915(dev);
 151         struct i915_ggtt *ggtt = &dev_priv->ggtt;
 152         struct drm_i915_gem_get_aperture *args = data;
 153         struct i915_vma *vma;
 154         size_t pinned;
 155
 156         pinned = 0;
 157         mutex_lock(&dev->struct_mutex);
 158         list_for_each_entry(vma, &ggtt->base.active_list, vm_link)
 159                 if (vma->pin_count)
 160                         pinned += vma->node.size;
 161         list_for_each_entry(vma, &ggtt->base.inactive_list, vm_link)
 162                 if (vma->pin_count)
 163                         pinned += vma->node.size;
 164         mutex_unlock(&dev->struct_mutex);
 165
 166         args->aper_size = ggtt->base.total;
 167         args->aper_available_size = args->aper_size - pinned;
 168
 169         return 0;
 170 }
 171
 172 static int
 173 i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
 174 {
 175         struct address_space *mapping = obj->base.filp->f_mapping;
 176         char *vaddr = obj->phys_handle->vaddr;
 177         struct sg_table *st;
 178         struct scatterlist *sg;
 179         int i;
 180
 181         if (WARN_ON(i915_gem_object_needs_bit17_swizzle(obj)))
 182                 return -EINVAL;
 183
 184         for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
 185                 struct page *page;
 186                 char *src;
 187
 188                 page = shmem_read_mapping_page(mapping, i);
 189                 if (IS_ERR(page))
 190                         return PTR_ERR(page);
 191
 192                 src = kmap_atomic(page);
 193                 memcpy(vaddr, src, PAGE_SIZE);
 194                 drm_clflush_virt_range(vaddr, PAGE_SIZE);
 195                 kunmap_atomic(src);
 196
 197                 put_page(page);
 198                 vaddr += PAGE_SIZE;
 199         }
 200
 201         i915_gem_chipset_flush(to_i915(obj->base.dev));
 202
 203         st = kmalloc(sizeof(*st), GFP_KERNEL);
 204         if (st == NULL)
 205                 return -ENOMEM;
 206
 207         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 208                 kfree(st);
 209                 return -ENOMEM;
 210         }
 211
 212         sg = st->sgl;
 213         sg->offset = 0;
 214         sg->length = obj->base.size;
 215
 216         sg_dma_address(sg) = obj->phys_handle->busaddr;
 217         sg_dma_len(sg) = obj->base.size;
 218
 219         obj->pages = st;
 220         return 0;
 221 }
 222
 223 static void
 224 i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj)
 225 {
 226         int ret;
 227
 228         BUG_ON(obj->madv == __I915_MADV_PURGED);
 229
 230         ret = i915_gem_object_set_to_cpu_domain(obj, true);
 231         if (WARN_ON(ret)) {
 232                 /* In the event of a disaster, abandon all caches and
 233                  * hope for the best.
 234                  */
 235                 obj->base.read_domains = obj->base.write_domain = I915_GEM_DOMAIN_CPU;
 236         }
 237
 238         if (obj->madv == I915_MADV_DONTNEED)
 239                 obj->dirty = 0;
 240
 241         if (obj->dirty) {
 242                 struct address_space *mapping = obj->base.filp->f_mapping;
 243                 char *vaddr = obj->phys_handle->vaddr;
 244                 int i;
 245
 246                 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
 247                         struct page *page;
 248                         char *dst;
 249
 250                         page = shmem_read_mapping_page(mapping, i);
 251                         if (IS_ERR(page))
 252                                 continue;
 253
 254                         dst = kmap_atomic(page);
 255                         drm_clflush_virt_range(vaddr, PAGE_SIZE);
 256                         memcpy(dst, vaddr, PAGE_SIZE);
 257                         kunmap_atomic(dst);
 258
 259                         set_page_dirty(page);
 260                         if (obj->madv == I915_MADV_WILLNEED)
 261                                 mark_page_accessed(page);
 262                         put_page(page);
 263                         vaddr += PAGE_SIZE;
 264                 }
 265                 obj->dirty = 0;
 266         }
 267
 268         sg_free_table(obj->pages);
 269         kfree(obj->pages);
 270 }
 271
 272 static void
 273 i915_gem_object_release_phys(struct drm_i915_gem_object *obj)
 274 {
 275         drm_pci_free(obj->base.dev, obj->phys_handle);
 276 }
 277
 278 static const struct drm_i915_gem_object_ops i915_gem_phys_ops = {
 279         .get_pages = i915_gem_object_get_pages_phys,
 280         .put_pages = i915_gem_object_put_pages_phys,
 281         .release = i915_gem_object_release_phys,
 282 };
 283
 284 static int
 285 drop_pages(struct drm_i915_gem_object *obj)
 286 {
 287         struct i915_vma *vma, *next;
 288         int ret;
 289
 290         drm_gem_object_reference(&obj->base);
 291         list_for_each_entry_safe(vma, next, &obj->vma_list, obj_link)
 292                 if (i915_vma_unbind(vma))
 293                         break;
 294
 295         ret = i915_gem_object_put_pages(obj);
 296         drm_gem_object_unreference(&obj->base);
 297
 298         return ret;
 299 }
 300
 301 int
 302 i915_gem_object_attach_phys(struct drm_i915_gem_object *obj,
 303                             int align)
 304 {
 305         drm_dma_handle_t *phys;
 306         int ret;
 307
 308         if (obj->phys_handle) {
 309                 if ((unsigned long)obj->phys_handle->vaddr & (align -1))
 310                         return -EBUSY;
 311
 312                 return 0;
 313         }
 314
 315         if (obj->madv != I915_MADV_WILLNEED)
 316                 return -EFAULT;
 317
 318         if (obj->base.filp == NULL)
 319                 return -EINVAL;
 320
 321         ret = drop_pages(obj);
 322         if (ret)
 323                 return ret;
 324
 325         /* create a new object */
 326         phys = drm_pci_alloc(obj->base.dev, obj->base.size, align);
 327         if (!phys)
 328                 return -ENOMEM;
 329
 330         obj->phys_handle = phys;
 331         obj->ops = &i915_gem_phys_ops;
 332
 333         return i915_gem_object_get_pages(obj);
 334 }
 335
 336 static int
 337 i915_gem_phys_pwrite(struct drm_i915_gem_object *obj,
 338                      struct drm_i915_gem_pwrite *args,
 339                      struct drm_file *file_priv)
 340 {
 341         struct drm_device *dev = obj->base.dev;
 342         void *vaddr = obj->phys_handle->vaddr + args->offset;
 343         char __user *user_data = u64_to_user_ptr(args->data_ptr);
 344         int ret = 0;
 345
 346         /* We manually control the domain here and pretend that it
 347          * remains coherent i.e. in the GTT domain, like shmem_pwrite.
 348          */
 349         ret = i915_gem_object_wait_rendering(obj, false);
 350         if (ret)
 351                 return ret;
 352
 353         intel_fb_obj_invalidate(obj, ORIGIN_CPU);
 354         if (__copy_from_user_inatomic_nocache(vaddr, user_data, args->size)) {
 355                 unsigned long unwritten;
 356
 357                 /* The physical object once assigned is fixed for the lifetime
 358                  * of the obj, so we can safely drop the lock and continue
 359                  * to access vaddr.
 360                  */
 361                 mutex_unlock(&dev->struct_mutex);
 362                 unwritten = copy_from_user(vaddr, user_data, args->size);
 363                 mutex_lock(&dev->struct_mutex);
 364                 if (unwritten) {
 365                         ret = -EFAULT;
 366                         goto out;
 367                 }
 368         }
 369
 370         drm_clflush_virt_range(vaddr, args->size);
 371         i915_gem_chipset_flush(to_i915(dev));
 372
 373 out:
 374         intel_fb_obj_flush(obj, false, ORIGIN_CPU);
 375         return ret;
 376 }
 377
 378 void *i915_gem_object_alloc(struct drm_device *dev)
 379 {
 380         struct drm_i915_private *dev_priv = to_i915(dev);
 381         return kmem_cache_zalloc(dev_priv->objects, GFP_KERNEL);
 382 }
 383
 384 void i915_gem_object_free(struct drm_i915_gem_object *obj)
 385 {
 386         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
 387         kmem_cache_free(dev_priv->objects, obj);
 388 }
 389
 390 static int
 391 i915_gem_create(struct drm_file *file,
 392                 struct drm_device *dev,
 393                 uint64_t size,
 394                 uint32_t *handle_p)
 395 {
 396         struct drm_i915_gem_object *obj;
 397         int ret;
 398         u32 handle;
 399
 400         size = roundup(size, PAGE_SIZE);
 401         if (size == 0)
 402                 return -EINVAL;
 403
 404         /* Allocate the new object */
 405         obj = i915_gem_object_create(dev, size);
 406         if (IS_ERR(obj))
 407                 return PTR_ERR(obj);
 408
 409         ret = drm_gem_handle_create(file, &obj->base, &handle);
 410         /* drop reference from allocate - handle holds it now */
 411         drm_gem_object_unreference_unlocked(&obj->base);
 412         if (ret)
 413                 return ret;
 414
 415         *handle_p = handle;
 416         return 0;
 417 }
 418
 419 int
 420 i915_gem_dumb_create(struct drm_file *file,
 421                      struct drm_device *dev,
 422                      struct drm_mode_create_dumb *args)
 423 {
 424         /* have to work out size/pitch and return them */
 425         args->pitch = ALIGN(args->width * DIV_ROUND_UP(args->bpp, 8), 64);
 426         args->size = args->pitch * args->height;
 427         return i915_gem_create(file, dev,
 428                                args->size, &args->handle);
 429 }
 430
 431 /**
 432  * Creates a new mm object and returns a handle to it.
 433  * @dev: drm device pointer
 434  * @data: ioctl data blob
 435  * @file: drm file pointer
 436  */
 437 int
 438 i915_gem_create_ioctl(struct drm_device *dev, void *data,
 439                       struct drm_file *file)
 440 {
 441         struct drm_i915_gem_create *args = data;
 442
 443         return i915_gem_create(file, dev,
 444                                args->size, &args->handle);
 445 }
 446
 447 static inline int
 448 __copy_to_user_swizzled(char __user *cpu_vaddr,
 449                         const char *gpu_vaddr, int gpu_offset,
 450                         int length)
 451 {
 452         int ret, cpu_offset = 0;
 453
 454         while (length > 0) {
 455                 int cacheline_end = ALIGN(gpu_offset + 1, 64);
 456                 int this_length = min(cacheline_end - gpu_offset, length);
 457                 int swizzled_gpu_offset = gpu_offset ^ 64;
 458
 459                 ret = __copy_to_user(cpu_vaddr + cpu_offset,
 460                                      gpu_vaddr + swizzled_gpu_offset,
 461                                      this_length);
 462                 if (ret)
 463                         return ret + length;
 464
 465                 cpu_offset += this_length;
 466                 gpu_offset += this_length;
 467                 length -= this_length;
 468         }
 469
 470         return 0;
 471 }
 472
 473 static inline int
 474 __copy_from_user_swizzled(char *gpu_vaddr, int gpu_offset,
 475                           const char __user *cpu_vaddr,
 476                           int length)
 477 {
 478         int ret, cpu_offset = 0;
 479
 480         while (length > 0) {
 481                 int cacheline_end = ALIGN(gpu_offset + 1, 64);
 482                 int this_length = min(cacheline_end - gpu_offset, length);
 483                 int swizzled_gpu_offset = gpu_offset ^ 64;
 484
 485                 ret = __copy_from_user(gpu_vaddr + swizzled_gpu_offset,
 486                                        cpu_vaddr + cpu_offset,
 487                                        this_length);
 488                 if (ret)
 489                         return ret + length;
 490
 491                 cpu_offset += this_length;
 492                 gpu_offset += this_length;
 493                 length -= this_length;
 494         }
 495
 496         return 0;
 497 }
 498
 499 /*
 500  * Pins the specified object's pages and synchronizes the object with
 501  * GPU accesses. Sets needs_clflush to non-zero if the caller should
 502  * flush the object from the CPU cache.
 503  */
 504 int i915_gem_obj_prepare_shmem_read(struct drm_i915_gem_object *obj,
 505                                     int *needs_clflush)
 506 {
 507         int ret;
 508
 509         *needs_clflush = 0;
 510
 511         if (WARN_ON(!i915_gem_object_has_struct_page(obj)))
 512                 return -EINVAL;
 513
 514         if (!(obj->base.read_domains & I915_GEM_DOMAIN_CPU)) {
 515                 /* If we're not in the cpu read domain, set ourself into the gtt
 516                  * read domain and manually flush cachelines (if required). This
 517                  * optimizes for the case when the gpu will dirty the data
 518                  * anyway again before the next pread happens. */
 519                 *needs_clflush = !cpu_cache_is_coherent(obj->base.dev,
 520                                                         obj->cache_level);
 521                 ret = i915_gem_object_wait_rendering(obj, true);
 522                 if (ret)
 523                         return ret;
 524         }
 525
 526         ret = i915_gem_object_get_pages(obj);
 527         if (ret)
 528                 return ret;
 529
 530         i915_gem_object_pin_pages(obj);
 531
 532         return ret;
 533 }
 534
 535 /* Per-page copy function for the shmem pread fastpath.
 536  * Flushes invalid cachelines before reading the target if
 537  * needs_clflush is set. */
 538 static int
 539 shmem_pread_fast(struct page *page, int shmem_page_offset, int page_length,
 540                  char __user *user_data,
 541                  bool page_do_bit17_swizzling, bool needs_clflush)
 542 {
 543         char *vaddr;
 544         int ret;
 545
 546         if (unlikely(page_do_bit17_swizzling))
 547                 return -EINVAL;
 548
 549         vaddr = kmap_atomic(page);
 550         if (needs_clflush)
 551                 drm_clflush_virt_range(vaddr + shmem_page_offset,
 552                                        page_length);
 553         ret = __copy_to_user_inatomic(user_data,
 554                                       vaddr + shmem_page_offset,
 555                                       page_length);
 556         kunmap_atomic(vaddr);
 557
 558         return ret ? -EFAULT : 0;
 559 }
 560
 561 static void
 562 shmem_clflush_swizzled_range(char *addr, unsigned long length,
 563                              bool swizzled)
 564 {
 565         if (unlikely(swizzled)) {
 566                 unsigned long start = (unsigned long) addr;
 567                 unsigned long end = (unsigned long) addr + length;
 568
 569                 /* For swizzling simply ensure that we always flush both
 570                  * channels. Lame, but simple and it works. Swizzled
 571                  * pwrite/pread is far from a hotpath - current userspace
 572                  * doesn't use it at all. */
 573                 start = round_down(start, 128);
 574                 end = round_up(end, 128);
 575
 576                 drm_clflush_virt_range((void *)start, end - start);
 577         } else {
 578                 drm_clflush_virt_range(addr, length);
 579         }
 580
 581 }
 582
 583 /* Only difference to the fast-path function is that this can handle bit17
 584  * and uses non-atomic copy and kmap functions. */
 585 static int
 586 shmem_pread_slow(struct page *page, int shmem_page_offset, int page_length,
 587                  char __user *user_data,
 588                  bool page_do_bit17_swizzling, bool needs_clflush)
 589 {
 590         char *vaddr;
 591         int ret;
 592
 593         vaddr = kmap(page);
 594         if (needs_clflush)
 595                 shmem_clflush_swizzled_range(vaddr + shmem_page_offset,
 596                                              page_length,
 597                                              page_do_bit17_swizzling);
 598
 599         if (page_do_bit17_swizzling)
 600                 ret = __copy_to_user_swizzled(user_data,
 601                                               vaddr, shmem_page_offset,
 602                                               page_length);
 603         else
 604                 ret = __copy_to_user(user_data,
 605                                      vaddr + shmem_page_offset,
 606                                      page_length);
 607         kunmap(page);
 608
 609         return ret ? - EFAULT : 0;
 610 }
 611
 612 static inline unsigned long
 613 slow_user_access(struct io_mapping *mapping,
 614                  uint64_t page_base, int page_offset,
 615                  char __user *user_data,
 616                  unsigned long length, bool pwrite)
 617 {
 618         void __iomem *ioaddr;
 619         void *vaddr;
 620         uint64_t unwritten;
 621
 622         ioaddr = io_mapping_map_wc(mapping, page_base, PAGE_SIZE);
 623         /* We can use the cpu mem copy function because this is X86. */
 624         vaddr = (void __force *)ioaddr + page_offset;
 625         if (pwrite)
 626                 unwritten = __copy_from_user(vaddr, user_data, length);
 627         else
 628                 unwritten = __copy_to_user(user_data, vaddr, length);
 629
 630         io_mapping_unmap(ioaddr);
 631         return unwritten;
 632 }
 633
 634 static int
 635 i915_gem_gtt_pread(struct drm_device *dev,
 636                    struct drm_i915_gem_object *obj, uint64_t size,
 637                    uint64_t data_offset, uint64_t data_ptr)
 638 {
 639         struct drm_i915_private *dev_priv = to_i915(dev);
 640         struct i915_ggtt *ggtt = &dev_priv->ggtt;
 641         struct drm_mm_node node;
 642         char __user *user_data;
 643         uint64_t remain;
 644         uint64_t offset;
 645         int ret;
 646
 647         ret = i915_gem_obj_ggtt_pin(obj, 0, PIN_MAPPABLE);
 648         if (ret) {
 649                 ret = insert_mappable_node(dev_priv, &node, PAGE_SIZE);
 650                 if (ret)
 651                         goto out;
 652
 653                 ret = i915_gem_object_get_pages(obj);
 654                 if (ret) {
 655                         remove_mappable_node(&node);
 656                         goto out;
 657                 }
 658
 659                 i915_gem_object_pin_pages(obj);
 660         } else {
 661                 node.start = i915_gem_obj_ggtt_offset(obj);
 662                 node.allocated = false;
 663                 ret = i915_gem_object_put_fence(obj);
 664                 if (ret)
 665                         goto out_unpin;
 666         }
 667
 668         ret = i915_gem_object_set_to_gtt_domain(obj, false);
 669         if (ret)
 670                 goto out_unpin;
 671
 672         user_data = u64_to_user_ptr(data_ptr);
 673         remain = size;
 674         offset = data_offset;
 675
 676         mutex_unlock(&dev->struct_mutex);
 677         if (likely(!i915.prefault_disable)) {
 678                 ret = fault_in_multipages_writeable(user_data, remain);
 679                 if (ret) {
 680                         mutex_lock(&dev->struct_mutex);
 681                         goto out_unpin;
 682                 }
 683         }
 684
 685         while (remain > 0) {
 686                 /* Operation in this page
 687                  *
 688                  * page_base = page offset within aperture
 689                  * page_offset = offset within page
 690                  * page_length = bytes to copy for this page
 691                  */
 692                 u32 page_base = node.start;
 693                 unsigned page_offset = offset_in_page(offset);
 694                 unsigned page_length = PAGE_SIZE - page_offset;
 695                 page_length = remain < page_length ? remain : page_length;
 696                 if (node.allocated) {
 697                         wmb();
 698                         ggtt->base.insert_page(&ggtt->base,
 699                                                i915_gem_object_get_dma_address(obj, offset >> PAGE_SHIFT),
 700                                                node.start,
 701                                                I915_CACHE_NONE, 0);
 702                         wmb();
 703                 } else {
 704                         page_base += offset & PAGE_MASK;
 705                 }
 706                 /* This is a slow read/write as it tries to read from
 707                  * and write to user memory which may result into page
 708                  * faults, and so we cannot perform this under struct_mutex.
 709                  */
 710                 if (slow_user_access(ggtt->mappable, page_base,
 711                                      page_offset, user_data,
 712                                      page_length, false)) {
 713                         ret = -EFAULT;
 714                         break;
 715                 }
 716
 717                 remain -= page_length;
 718                 user_data += page_length;
 719                 offset += page_length;
 720         }
 721
 722         mutex_lock(&dev->struct_mutex);
 723         if (ret == 0 && (obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0) {
 724                 /* The user has modified the object whilst we tried
 725                  * reading from it, and we now have no idea what domain
 726                  * the pages should be in. As we have just been touching
 727                  * them directly, flush everything back to the GTT
 728                  * domain.
 729                  */
 730                 ret = i915_gem_object_set_to_gtt_domain(obj, false);
 731         }
 732
 733 out_unpin:
 734         if (node.allocated) {
 735                 wmb();
 736                 ggtt->base.clear_range(&ggtt->base,
 737                                        node.start, node.size,
 738                                        true);
 739                 i915_gem_object_unpin_pages(obj);
 740                 remove_mappable_node(&node);
 741         } else {
 742                 i915_gem_object_ggtt_unpin(obj);
 743         }
 744 out:
 745         return ret;
 746 }
 747
 748 static int
 749 i915_gem_shmem_pread(struct drm_device *dev,
 750                      struct drm_i915_gem_object *obj,
 751                      struct drm_i915_gem_pread *args,
 752                      struct drm_file *file)
 753 {
 754         char __user *user_data;
 755         ssize_t remain;
 756         loff_t offset;
 757         int shmem_page_offset, page_length, ret = 0;
 758         int obj_do_bit17_swizzling, page_do_bit17_swizzling;
 759         int prefaulted = 0;
 760         int needs_clflush = 0;
 761         struct sg_page_iter sg_iter;
 762
 763         if (!i915_gem_object_has_struct_page(obj))
 764                 return -ENODEV;
 765
 766         user_data = u64_to_user_ptr(args->data_ptr);
 767         remain = args->size;
 768
 769         obj_do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj);
 770
 771         ret = i915_gem_obj_prepare_shmem_read(obj, &needs_clflush);
 772         if (ret)
 773                 return ret;
 774
 775         offset = args->offset;
 776
 777         for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents,
 778                          offset >> PAGE_SHIFT) {
 779                 struct page *page = sg_page_iter_page(&sg_iter);
 780
 781                 if (remain <= 0)
 782                         break;
 783
 784                 /* Operation in this page
 785                  *
 786                  * shmem_page_offset = offset within page in shmem file
 787                  * page_length = bytes to copy for this page
 788                  */
 789                 shmem_page_offset = offset_in_page(offset);
 790                 page_length = remain;
 791                 if ((shmem_page_offset + page_length) > PAGE_SIZE)
 792                         page_length = PAGE_SIZE - shmem_page_offset;
 793
 794                 page_do_bit17_swizzling = obj_do_bit17_swizzling &&
 795                         (page_to_phys(page) & (1 << 17)) != 0;
 796
 797                 ret = shmem_pread_fast(page, shmem_page_offset, page_length,
 798                                        user_data, page_do_bit17_swizzling,
 799                                        needs_clflush);
 800                 if (ret == 0)
 801                         goto next_page;
 802
 803                 mutex_unlock(&dev->struct_mutex);
 804
 805                 if (likely(!i915.prefault_disable) && !prefaulted) {
 806                         ret = fault_in_multipages_writeable(user_data, remain);
 807                         /* Userspace is tricking us, but we've already clobbered
 808                          * its pages with the prefault and promised to write the
 809                          * data up to the first fault. Hence ignore any errors
 810                          * and just continue. */
 811                         (void)ret;
 812                         prefaulted = 1;
 813                 }
 814
 815                 ret = shmem_pread_slow(page, shmem_page_offset, page_length,
 816                                        user_data, page_do_bit17_swizzling,
 817                                        needs_clflush);
 818
 819                 mutex_lock(&dev->struct_mutex);
 820
 821                 if (ret)
 822                         goto out;
 823
 824 next_page:
 825                 remain -= page_length;
 826                 user_data += page_length;
 827                 offset += page_length;
 828         }
 829
 830 out:
 831         i915_gem_object_unpin_pages(obj);
 832
 833         return ret;
 834 }
 835
 836 /**
 837  * Reads data from the object referenced by handle.
 838  * @dev: drm device pointer
 839  * @data: ioctl data blob
 840  * @file: drm file pointer
 841  *
 842  * On error, the contents of *data are undefined.
 843  */
 844 int
 845 i915_gem_pread_ioctl(struct drm_device *dev, void *data,
 846                      struct drm_file *file)
 847 {
 848         struct drm_i915_gem_pread *args = data;
 849         struct drm_i915_gem_object *obj;
 850         int ret = 0;
 851
 852         if (args->size == 0)
 853                 return 0;
 854
 855         if (!access_ok(VERIFY_WRITE,
 856                        u64_to_user_ptr(args->data_ptr),
 857                        args->size))
 858                 return -EFAULT;
 859
 860         ret = i915_mutex_lock_interruptible(dev);
 861         if (ret)
 862                 return ret;
 863
 864         obj = to_intel_bo(drm_gem_object_lookup(file, args->handle));
 865         if (&obj->base == NULL) {
 866                 ret = -ENOENT;
 867                 goto unlock;
 868         }
 869
 870         /* Bounds check source.  */
 871         if (args->offset > obj->base.size ||
 872             args->size > obj->base.size - args->offset) {
 873                 ret = -EINVAL;
 874                 goto out;
 875         }
 876
 877         trace_i915_gem_object_pread(obj, args->offset, args->size);
 878
 879         ret = i915_gem_shmem_pread(dev, obj, args, file);
 880
 881         /* pread for non shmem backed objects */
 882         if (ret == -EFAULT || ret == -ENODEV)
 883                 ret = i915_gem_gtt_pread(dev, obj, args->size,
 884                                         args->offset, args->data_ptr);
 885
 886 out:
 887         drm_gem_object_unreference(&obj->base);
 888 unlock:
 889         mutex_unlock(&dev->struct_mutex);
 890         return ret;
 891 }
 892
 893 /* This is the fast write path which cannot handle
 894  * page faults in the source data
 895  */
 896
 897 static inline int
 898 fast_user_write(struct io_mapping *mapping,
 899                 loff_t page_base, int page_offset,
 900                 char __user *user_data,
 901                 int length)
 902 {
 903         void __iomem *vaddr_atomic;
 904         void *vaddr;
 905         unsigned long unwritten;
 906
 907         vaddr_atomic = io_mapping_map_atomic_wc(mapping, page_base);
 908         /* We can use the cpu mem copy function because this is X86. */
 909         vaddr = (void __force*)vaddr_atomic + page_offset;
 910         unwritten = __copy_from_user_inatomic_nocache(vaddr,
 911                                                       user_data, length);
 912         io_mapping_unmap_atomic(vaddr_atomic);
 913         return unwritten;
 914 }
 915
 916 /**
 917  * This is the fast pwrite path, where we copy the data directly from the
 918  * user into the GTT, uncached.
 919  * @dev: drm device pointer
 920  * @obj: i915 gem object
 921  * @args: pwrite arguments structure
 922  * @file: drm file pointer
 923  */
 924 static int
 925 i915_gem_gtt_pwrite_fast(struct drm_i915_private *i915,
 926                          struct drm_i915_gem_object *obj,
 927                          struct drm_i915_gem_pwrite *args,
 928                          struct drm_file *file)
 929 {
 930         struct i915_ggtt *ggtt = &i915->ggtt;
 931         struct drm_device *dev = obj->base.dev;
 932         struct drm_mm_node node;
 933         uint64_t remain, offset;
 934         char __user *user_data;
 935         int ret;
 936         bool hit_slow_path = false;
 937
 938         if (obj->tiling_mode != I915_TILING_NONE)
 939                 return -EFAULT;
 940
 941         ret = i915_gem_obj_ggtt_pin(obj, 0, PIN_MAPPABLE | PIN_NONBLOCK);
 942         if (ret) {
 943                 ret = insert_mappable_node(i915, &node, PAGE_SIZE);
 944                 if (ret)
 945                         goto out;
 946
 947                 ret = i915_gem_object_get_pages(obj);
 948                 if (ret) {
 949                         remove_mappable_node(&node);
 950                         goto out;
 951                 }
 952
 953                 i915_gem_object_pin_pages(obj);
 954         } else {
 955                 node.start = i915_gem_obj_ggtt_offset(obj);
 956                 node.allocated = false;
 957                 ret = i915_gem_object_put_fence(obj);
 958                 if (ret)
 959                         goto out_unpin;
 960         }
 961
 962         ret = i915_gem_object_set_to_gtt_domain(obj, true);
 963         if (ret)
 964                 goto out_unpin;
 965
 966         intel_fb_obj_invalidate(obj, ORIGIN_GTT);
 967         obj->dirty = true;
 968
 969         user_data = u64_to_user_ptr(args->data_ptr);
 970         offset = args->offset;
 971         remain = args->size;
 972         while (remain) {
 973                 /* Operation in this page
 974                  *
 975                  * page_base = page offset within aperture
 976                  * page_offset = offset within page
 977                  * page_length = bytes to copy for this page
 978                  */
 979                 u32 page_base = node.start;
 980                 unsigned page_offset = offset_in_page(offset);
 981                 unsigned page_length = PAGE_SIZE - page_offset;
 982                 page_length = remain < page_length ? remain : page_length;
 983                 if (node.allocated) {
 984                         wmb(); /* flush the write before we modify the GGTT */
 985                         ggtt->base.insert_page(&ggtt->base,
 986                                                i915_gem_object_get_dma_address(obj, offset >> PAGE_SHIFT),
 987                                                node.start, I915_CACHE_NONE, 0);
 988                         wmb(); /* flush modifications to the GGTT (insert_page) */
 989                 } else {
 990                         page_base += offset & PAGE_MASK;
 991                 }
 992                 /* If we get a fault while copying data, then (presumably) our
 993                  * source page isn't available.  Return the error and we'll
 994                  * retry in the slow path.
 995                  * If the object is non-shmem backed, we retry again with the
 996                  * path that handles page fault.
 997                  */
 998                 if (fast_user_write(ggtt->mappable, page_base,
 999                                     page_offset, user_data, page_length)) {
1000                         hit_slow_path = true;
1001                         mutex_unlock(&dev->struct_mutex);
1002                         if (slow_user_access(ggtt->mappable,
1003                                              page_base,
1004                                              page_offset, user_data,
1005                                              page_length, true)) {
1006                                 ret = -EFAULT;
1007                                 mutex_lock(&dev->struct_mutex);
1008                                 goto out_flush;
1009                         }
1010
1011                         mutex_lock(&dev->struct_mutex);
1012                 }
1013
1014                 remain -= page_length;
1015                 user_data += page_length;
1016                 offset += page_length;
1017         }
1018
1019 out_flush:
1020         if (hit_slow_path) {
1021                 if (ret == 0 &&
1022                     (obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0) {
1023                         /* The user has modified the object whilst we tried
1024                          * reading from it, and we now have no idea what domain
1025                          * the pages should be in. As we have just been touching
1026                          * them directly, flush everything back to the GTT
1027                          * domain.
1028                          */
1029                         ret = i915_gem_object_set_to_gtt_domain(obj, false);
1030                 }
1031         }
1032
1033         intel_fb_obj_flush(obj, false, ORIGIN_GTT);
1034 out_unpin:
1035         if (node.allocated) {
1036                 wmb();
1037                 ggtt->base.clear_range(&ggtt->base,
1038                                        node.start, node.size,
1039                                        true);
1040                 i915_gem_object_unpin_pages(obj);
1041                 remove_mappable_node(&node);
1042         } else {
1043                 i915_gem_object_ggtt_unpin(obj);
1044         }
1045 out:
1046         return ret;
1047 }
1048
1049 /* Per-page copy function for the shmem pwrite fastpath.
1050  * Flushes invalid cachelines before writing to the target if
1051  * needs_clflush_before is set and flushes out any written cachelines after
1052  * writing if needs_clflush is set. */
1053 static int
1054 shmem_pwrite_fast(struct page *page, int shmem_page_offset, int page_length,
1055                   char __user *user_data,
1056                   bool page_do_bit17_swizzling,
1057                   bool needs_clflush_before,
1058                   bool needs_clflush_after)
1059 {
1060         char *vaddr;
1061         int ret;
1062
1063         if (unlikely(page_do_bit17_swizzling))
1064                 return -EINVAL;
1065
1066         vaddr = kmap_atomic(page);
1067         if (needs_clflush_before)
1068                 drm_clflush_virt_range(vaddr + shmem_page_offset,
1069                                        page_length);
1070         ret = __copy_from_user_inatomic(vaddr + shmem_page_offset,
1071                                         user_data, page_length);
1072         if (needs_clflush_after)
1073                 drm_clflush_virt_range(vaddr + shmem_page_offset,
1074                                        page_length);
1075         kunmap_atomic(vaddr);
1076
1077         return ret ? -EFAULT : 0;
1078 }
1079
1080 /* Only difference to the fast-path function is that this can handle bit17
1081  * and uses non-atomic copy and kmap functions. */
1082 static int
1083 shmem_pwrite_slow(struct page *page, int shmem_page_offset, int page_length,
1084                   char __user *user_data,
1085                   bool page_do_bit17_swizzling,
1086                   bool needs_clflush_before,
1087                   bool needs_clflush_after)
1088 {
1089         char *vaddr;
1090         int ret;
1091
1092         vaddr = kmap(page);
1093         if (unlikely(needs_clflush_before || page_do_bit17_swizzling))
1094                 shmem_clflush_swizzled_range(vaddr + shmem_page_offset,
1095                                              page_length,
1096                                              page_do_bit17_swizzling);
1097         if (page_do_bit17_swizzling)
1098                 ret = __copy_from_user_swizzled(vaddr, shmem_page_offset,
1099                                                 user_data,
1100                                                 page_length);
1101         else
1102                 ret = __copy_from_user(vaddr + shmem_page_offset,
1103                                        user_data,
1104                                        page_length);
1105         if (needs_clflush_after)
1106                 shmem_clflush_swizzled_range(vaddr + shmem_page_offset,
1107                                              page_length,
1108                                              page_do_bit17_swizzling);
1109         kunmap(page);
1110
1111         return ret ? -EFAULT : 0;
1112 }
1113
1114 static int
1115 i915_gem_shmem_pwrite(struct drm_device *dev,
1116                       struct drm_i915_gem_object *obj,
1117                       struct drm_i915_gem_pwrite *args,
1118                       struct drm_file *file)
1119 {
1120         ssize_t remain;
1121         loff_t offset;
1122         char __user *user_data;
1123         int shmem_page_offset, page_length, ret = 0;
1124         int obj_do_bit17_swizzling, page_do_bit17_swizzling;
1125         int hit_slowpath = 0;
1126         int needs_clflush_after = 0;
1127         int needs_clflush_before = 0;
1128         struct sg_page_iter sg_iter;
1129
1130         user_data = u64_to_user_ptr(args->data_ptr);
1131         remain = args->size;
1132
1133         obj_do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj);
1134
1135         if (obj->base.write_domain != I915_GEM_DOMAIN_CPU) {
1136                 /* If we're not in the cpu write domain, set ourself into the gtt
1137                  * write domain and manually flush cachelines (if required). This
1138                  * optimizes for the case when the gpu will use the data
1139                  * right away and we therefore have to clflush anyway. */
1140                 needs_clflush_after = cpu_write_needs_clflush(obj);
1141                 ret = i915_gem_object_wait_rendering(obj, false);
1142                 if (ret)
1143                         return ret;
1144         }
1145         /* Same trick applies to invalidate partially written cachelines read
1146          * before writing. */
1147         if ((obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0)
1148                 needs_clflush_before =
1149                         !cpu_cache_is_coherent(dev, obj->cache_level);
1150
1151         ret = i915_gem_object_get_pages(obj);
1152         if (ret)
1153                 return ret;
1154
1155         intel_fb_obj_invalidate(obj, ORIGIN_CPU);
1156
1157         i915_gem_object_pin_pages(obj);
1158
1159         offset = args->offset;
1160         obj->dirty = 1;
1161
1162         for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents,
1163                          offset >> PAGE_SHIFT) {
1164                 struct page *page = sg_page_iter_page(&sg_iter);
1165                 int partial_cacheline_write;
1166
1167                 if (remain <= 0)
1168                         break;
1169
1170                 /* Operation in this page
1171                  *
1172                  * shmem_page_offset = offset within page in shmem file
1173                  * page_length = bytes to copy for this page
1174                  */
1175                 shmem_page_offset = offset_in_page(offset);
1176
1177                 page_length = remain;
1178                 if ((shmem_page_offset + page_length) > PAGE_SIZE)
1179                         page_length = PAGE_SIZE - shmem_page_offset;
1180
1181                 /* If we don't overwrite a cacheline completely we need to be
1182                  * careful to have up-to-date data by first clflushing. Don't
1183                  * overcomplicate things and flush the entire patch. */
1184                 partial_cacheline_write = needs_clflush_before &&
1185                         ((shmem_page_offset | page_length)
1186                                 & (boot_cpu_data.x86_clflush_size - 1));
1187
1188                 page_do_bit17_swizzling = obj_do_bit17_swizzling &&
1189                         (page_to_phys(page) & (1 << 17)) != 0;
1190
1191                 ret = shmem_pwrite_fast(page, shmem_page_offset, page_length,
1192                                         user_data, page_do_bit17_swizzling,
1193                                         partial_cacheline_write,
1194                                         needs_clflush_after);
1195                 if (ret == 0)
1196                         goto next_page;
1197
1198                 hit_slowpath = 1;
1199                 mutex_unlock(&dev->struct_mutex);
1200                 ret = shmem_pwrite_slow(page, shmem_page_offset, page_length,
1201                                         user_data, page_do_bit17_swizzling,
1202                                         partial_cacheline_write,
1203                                         needs_clflush_after);
1204
1205                 mutex_lock(&dev->struct_mutex);
1206
1207                 if (ret)
1208                         goto out;
1209
1210 next_page:
1211                 remain -= page_length;
1212                 user_data += page_length;
1213                 offset += page_length;
1214         }
1215
1216 out:
1217         i915_gem_object_unpin_pages(obj);
1218
1219         if (hit_slowpath) {
1220                 /*
1221                  * Fixup: Flush cpu caches in case we didn't flush the dirty
1222                  * cachelines in-line while writing and the object moved
1223                  * out of the cpu write domain while we've dropped the lock.
1224                  */
1225                 if (!needs_clflush_after &&
1226                     obj->base.write_domain != I915_GEM_DOMAIN_CPU) {
1227                         if (i915_gem_clflush_object(obj, obj->pin_display))
1228                                 needs_clflush_after = true;
1229                 }
1230         }
1231
1232         if (needs_clflush_after)
1233                 i915_gem_chipset_flush(to_i915(dev));
1234         else
1235                 obj->cache_dirty = true;
1236
1237         intel_fb_obj_flush(obj, false, ORIGIN_CPU);
1238         return ret;
1239 }
1240
1241 /**
1242  * Writes data to the object referenced by handle.
1243  * @dev: drm device
1244  * @data: ioctl data blob
1245  * @file: drm file
1246  *
1247  * On error, the contents of the buffer that were to be modified are undefined.
1248  */
1249 int
1250 i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
1251                       struct drm_file *file)
1252 {
1253         struct drm_i915_private *dev_priv = to_i915(dev);
1254         struct drm_i915_gem_pwrite *args = data;
1255         struct drm_i915_gem_object *obj;
1256         int ret;
1257
1258         if (args->size == 0)
1259                 return 0;
1260
1261         if (!access_ok(VERIFY_READ,
1262                        u64_to_user_ptr(args->data_ptr),
1263                        args->size))
1264                 return -EFAULT;
1265
1266         if (likely(!i915.prefault_disable)) {
1267                 ret = fault_in_multipages_readable(u64_to_user_ptr(args->data_ptr),
1268                                                    args->size);
1269                 if (ret)
1270                         return -EFAULT;
1271         }
1272
1273         intel_runtime_pm_get(dev_priv);
1274
1275         ret = i915_mutex_lock_interruptible(dev);
1276         if (ret)
1277                 goto put_rpm;
1278
1279         obj = to_intel_bo(drm_gem_object_lookup(file, args->handle));
1280         if (&obj->base == NULL) {
1281                 ret = -ENOENT;
1282                 goto unlock;
1283         }
1284
1285         /* Bounds check destination. */
1286         if (args->offset > obj->base.size ||
1287             args->size > obj->base.size - args->offset) {
1288                 ret = -EINVAL;
1289                 goto out;
1290         }
1291
1292         trace_i915_gem_object_pwrite(obj, args->offset, args->size);
1293
1294         ret = -EFAULT;
1295         /* We can only do the GTT pwrite on untiled buffers, as otherwise
1296          * it would end up going through the fenced access, and we'll get
1297          * different detiling behavior between reading and writing.
1298          * pread/pwrite currently are reading and writing from the CPU
1299          * perspective, requiring manual detiling by the client.
1300          */
1301         if (!i915_gem_object_has_struct_page(obj) ||
1302             cpu_write_needs_clflush(obj)) {
1303                 ret = i915_gem_gtt_pwrite_fast(dev_priv, obj, args, file);
1304                 /* Note that the gtt paths might fail with non-page-backed user
1305                  * pointers (e.g. gtt mappings when moving data between
1306                  * textures). Fallback to the shmem path in that case. */
1307         }
1308
1309         if (ret == -EFAULT || ret == -ENOSPC) {
1310                 if (obj->phys_handle)
1311                         ret = i915_gem_phys_pwrite(obj, args, file);
1312                 else if (i915_gem_object_has_struct_page(obj))
1313                         ret = i915_gem_shmem_pwrite(dev, obj, args, file);
1314                 else
1315                         ret = -ENODEV;
1316         }
1317
1318 out:
1319         drm_gem_object_unreference(&obj->base);
1320 unlock:
1321         mutex_unlock(&dev->struct_mutex);
1322 put_rpm:
1323         intel_runtime_pm_put(dev_priv);
1324
1325         return ret;
1326 }
1327
1328 static int
1329 i915_gem_check_wedge(unsigned reset_counter, bool interruptible)
1330 {
1331         if (__i915_terminally_wedged(reset_counter))
1332                 return -EIO;
1333
1334         if (__i915_reset_in_progress(reset_counter)) {
1335                 /* Non-interruptible callers can't handle -EAGAIN, hence return
1336                  * -EIO unconditionally for these. */
1337                 if (!interruptible)
1338                         return -EIO;
1339
1340                 return -EAGAIN;
1341         }
1342
1343         return 0;
1344 }
1345
1346 static unsigned long local_clock_us(unsigned *cpu)
1347 {
1348         unsigned long t;
1349
1350         /* Cheaply and approximately convert from nanoseconds to microseconds.
1351          * The result and subsequent calculations are also defined in the same
1352          * approximate microseconds units. The principal source of timing
1353          * error here is from the simple truncation.
1354          *
1355          * Note that local_clock() is only defined wrt to the current CPU;
1356          * the comparisons are no longer valid if we switch CPUs. Instead of
1357          * blocking preemption for the entire busywait, we can detect the CPU
1358          * switch and use that as indicator of system load and a reason to
1359          * stop busywaiting, see busywait_stop().
1360          */
1361         *cpu = get_cpu();
1362         t = local_clock() >> 10;
1363         put_cpu();
1364
1365         return t;
1366 }
1367
1368 static bool busywait_stop(unsigned long timeout, unsigned cpu)
1369 {
1370         unsigned this_cpu;
1371
1372         if (time_after(local_clock_us(&this_cpu), timeout))
1373                 return true;
1374
1375         return this_cpu != cpu;
1376 }
1377
1378 bool __i915_spin_request(const struct drm_i915_gem_request *req,
1379                          int state, unsigned long timeout_us)
1380 {
1381         unsigned cpu;
1382
1383         /* When waiting for high frequency requests, e.g. during synchronous
1384          * rendering split between the CPU and GPU, the finite amount of time
1385          * required to set up the irq and wait upon it limits the response
1386          * rate. By busywaiting on the request completion for a short while we
1387          * can service the high frequency waits as quick as possible. However,
1388          * if it is a slow request, we want to sleep as quickly as possible.
1389          * The tradeoff between waiting and sleeping is roughly the time it
1390          * takes to sleep on a request, on the order of a microsecond.
1391          */
1392
1393         timeout_us += local_clock_us(&cpu);
1394         do {
1395                 if (i915_gem_request_completed(req))
1396                         return true;
1397
1398                 if (signal_pending_state(state, current))
1399                         break;
1400
1401                 if (busywait_stop(timeout_us, cpu))
1402                         break;
1403
1404                 cpu_relax_lowlatency();
1405         } while (!need_resched());
1406
1407         return false;
1408 }
1409
1410 /**
1411  * __i915_wait_request - wait until execution of request has finished
1412  * @req: duh!
1413  * @interruptible: do an interruptible wait (normally yes)
1414  * @timeout: in - how long to wait (NULL forever); out - how much time remaining
1415  * @rps: RPS client
1416  *
1417  * Note: It is of utmost importance that the passed in seqno and reset_counter
1418  * values have been read by the caller in an smp safe manner. Where read-side
1419  * locks are involved, it is sufficient to read the reset_counter before
1420  * unlocking the lock that protects the seqno. For lockless tricks, the
1421  * reset_counter _must_ be read before, and an appropriate smp_rmb must be
1422  * inserted.
1423  *
1424  * Returns 0 if the request was found within the alloted time. Else returns the
1425  * errno with remaining time filled in timeout argument.
1426  */
1427 int __i915_wait_request(struct drm_i915_gem_request *req,
1428                         bool interruptible,
1429                         s64 *timeout,
1430                         struct intel_rps_client *rps)
1431 {
1432         int state = interruptible ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE;
1433         DEFINE_WAIT(reset);
1434         struct intel_wait wait;
1435         unsigned long timeout_remain;
1436         s64 before = 0; /* Only to silence a compiler warning. */
1437         int ret = 0;
1438
1439         might_sleep();
1440
1441         if (list_empty(&req->list))
1442                 return 0;
1443
1444         if (i915_gem_request_completed(req))
1445                 return 0;
1446
1447         timeout_remain = MAX_SCHEDULE_TIMEOUT;
1448         if (timeout) {
1449                 if (WARN_ON(*timeout < 0))
1450                         return -EINVAL;
1451
1452                 if (*timeout == 0)
1453                         return -ETIME;
1454
1455                 timeout_remain = nsecs_to_jiffies_timeout(*timeout);
1456
1457                 /*
1458                  * Record current time in case interrupted by signal, or wedged.
1459                  */
1460                 before = ktime_get_raw_ns();
1461         }
1462
1463         trace_i915_gem_request_wait_begin(req);
1464
1465         /* This client is about to stall waiting for the GPU. In many cases
1466          * this is undesirable and limits the throughput of the system, as
1467          * many clients cannot continue processing user input/output whilst
1468          * blocked. RPS autotuning may take tens of milliseconds to respond
1469          * to the GPU load and thus incurs additional latency for the client.
1470          * We can circumvent that by promoting the GPU frequency to maximum
1471          * before we wait. This makes the GPU throttle up much more quickly
1472          * (good for benchmarks and user experience, e.g. window animations),
1473          * but at a cost of spending more power processing the workload
1474          * (bad for battery). Not all clients even want their results
1475          * immediately and for them we should just let the GPU select its own
1476          * frequency to maximise efficiency. To prevent a single client from
1477          * forcing the clocks too high for the whole system, we only allow
1478          * each client to waitboost once in a busy period.
1479          */
1480         if (INTEL_INFO(req->i915)->gen >= 6)
1481                 gen6_rps_boost(req->i915, rps, req->emitted_jiffies);
1482
1483         /* Optimistic spin for the next ~jiffie before touching IRQs */
1484         if (i915_spin_request(req, state, 5))
1485                 goto complete;
1486
1487         set_current_state(state);
1488         add_wait_queue(&req->i915->gpu_error.wait_queue, &reset);
1489
1490         intel_wait_init(&wait, req->seqno);
1491         if (intel_engine_add_wait(req->engine, &wait))
1492                 /* In order to check that we haven't missed the interrupt
1493                  * as we enabled it, we need to kick ourselves to do a
1494                  * coherent check on the seqno before we sleep.
1495                  */
1496                 goto wakeup;
1497
1498         for (;;) {
1499                 if (signal_pending_state(state, current)) {
1500                         ret = -ERESTARTSYS;
1501                         break;
1502                 }
1503
1504                 timeout_remain = io_schedule_timeout(timeout_remain);
1505                 if (timeout_remain == 0) {
1506                         ret = -ETIME;
1507                         break;
1508                 }
1509
1510                 if (intel_wait_complete(&wait))
1511                         break;
1512
1513                 set_current_state(state);
1514
1515 wakeup:
1516                 /* Carefully check if the request is complete, giving time
1517                  * for the seqno to be visible following the interrupt.
1518                  * We also have to check in case we are kicked by the GPU
1519                  * reset in order to drop the struct_mutex.
1520                  */
1521                 if (__i915_request_irq_complete(req))
1522                         break;
1523
1524                 /* Only spin if we know the GPU is processing this request */
1525                 if (i915_spin_request(req, state, 2))
1526                         break;
1527         }
1528         remove_wait_queue(&req->i915->gpu_error.wait_queue, &reset);
1529
1530         intel_engine_remove_wait(req->engine, &wait);
1531         __set_current_state(TASK_RUNNING);
1532 complete:
1533         trace_i915_gem_request_wait_end(req);
1534
1535         if (timeout) {
1536                 s64 tres = *timeout - (ktime_get_raw_ns() - before);
1537
1538                 *timeout = tres < 0 ? 0 : tres;
1539
1540                 /*
1541                  * Apparently ktime isn't accurate enough and occasionally has a
1542                  * bit of mismatch in the jiffies<->nsecs<->ktime loop. So patch
1543                  * things up to make the test happy. We allow up to 1 jiffy.
1544                  *
1545                  * This is a regrssion from the timespec->ktime conversion.
1546                  */
1547                 if (ret == -ETIME && *timeout < jiffies_to_usecs(1)*1000)
1548                         *timeout = 0;
1549         }
1550
1551         if (rps && req->seqno == req->engine->last_submitted_seqno) {
1552                 /* The GPU is now idle and this client has stalled.
1553                  * Since no other client has submitted a request in the
1554                  * meantime, assume that this client is the only one
1555                  * supplying work to the GPU but is unable to keep that
1556                  * work supplied because it is waiting. Since the GPU is
1557                  * then never kept fully busy, RPS autoclocking will
1558                  * keep the clocks relatively low, causing further delays.
1559                  * Compensate by giving the synchronous client credit for
1560                  * a waitboost next time.
1561                  */
1562                 spin_lock(&req->i915->rps.client_lock);
1563                 list_del_init(&rps->link);
1564                 spin_unlock(&req->i915->rps.client_lock);
1565         }
1566
1567         return ret;
1568 }
1569
1570 int i915_gem_request_add_to_client(struct drm_i915_gem_request *req,
1571                                    struct drm_file *file)
1572 {
1573         struct drm_i915_file_private *file_priv;
1574
1575         WARN_ON(!req || !file || req->file_priv);
1576
1577         if (!req || !file)
1578                 return -EINVAL;
1579
1580         if (req->file_priv)
1581                 return -EINVAL;
1582
1583         file_priv = file->driver_priv;
1584
1585         spin_lock(&file_priv->mm.lock);
1586         req->file_priv = file_priv;
1587         list_add_tail(&req->client_list, &file_priv->mm.request_list);
1588         spin_unlock(&file_priv->mm.lock);
1589
1590         req->pid = get_pid(task_pid(current));
1591
1592         return 0;
1593 }
1594
1595 static inline void
1596 i915_gem_request_remove_from_client(struct drm_i915_gem_request *request)
1597 {
1598         struct drm_i915_file_private *file_priv = request->file_priv;
1599
1600         if (!file_priv)
1601                 return;
1602
1603         spin_lock(&file_priv->mm.lock);
1604         list_del(&request->client_list);
1605         request->file_priv = NULL;
1606         spin_unlock(&file_priv->mm.lock);
1607
1608         put_pid(request->pid);
1609         request->pid = NULL;
1610 }
1611
1612 static void i915_gem_request_retire(struct drm_i915_gem_request *request)
1613 {
1614         trace_i915_gem_request_retire(request);
1615
1616         /* We know the GPU must have read the request to have
1617          * sent us the seqno + interrupt, so use the position
1618          * of tail of the request to update the last known position
1619          * of the GPU head.
1620          *
1621          * Note this requires that we are always called in request
1622          * completion order.
1623          */
1624         request->ringbuf->last_retired_head = request->postfix;
1625
1626         list_del_init(&request->list);
1627         i915_gem_request_remove_from_client(request);
1628
1629         if (request->previous_context) {
1630                 if (i915.enable_execlists)
1631                         intel_lr_context_unpin(request->previous_context,
1632                                                request->engine);
1633         }
1634
1635         i915_gem_context_unreference(request->ctx);
1636         i915_gem_request_unreference(request);
1637 }
1638
1639 static void
1640 __i915_gem_request_retire__upto(struct drm_i915_gem_request *req)
1641 {
1642         struct intel_engine_cs *engine = req->engine;
1643         struct drm_i915_gem_request *tmp;
1644
1645         lockdep_assert_held(&engine->i915->drm.struct_mutex);
1646
1647         if (list_empty(&req->list))
1648                 return;
1649
1650         do {
1651                 tmp = list_first_entry(&engine->request_list,
1652                                        typeof(*tmp), list);
1653
1654                 i915_gem_request_retire(tmp);
1655         } while (tmp != req);
1656
1657         WARN_ON(i915_verify_lists(engine->dev));
1658 }
1659
1660 /**
1661  * Waits for a request to be signaled, and cleans up the
1662  * request and object lists appropriately for that event.
1663  * @req: request to wait on
1664  */
1665 int
1666 i915_wait_request(struct drm_i915_gem_request *req)
1667 {
1668         struct drm_i915_private *dev_priv = req->i915;
1669         bool interruptible;
1670         int ret;
1671
1672         interruptible = dev_priv->mm.interruptible;
1673
1674         BUG_ON(!mutex_is_locked(&dev_priv->drm.struct_mutex));
1675
1676         ret = __i915_wait_request(req, interruptible, NULL, NULL);
1677         if (ret)
1678                 return ret;
1679
1680         /* If the GPU hung, we want to keep the requests to find the guilty. */
1681         if (!i915_reset_in_progress(&dev_priv->gpu_error))
1682                 __i915_gem_request_retire__upto(req);
1683
1684         return 0;
1685 }
1686
1687 /**
1688  * Ensures that all rendering to the object has completed and the object is
1689  * safe to unbind from the GTT or access from the CPU.
1690  * @obj: i915 gem object
1691  * @readonly: waiting for read access or write
1692  */
1693 int
1694 i915_gem_object_wait_rendering(struct drm_i915_gem_object *obj,
1695                                bool readonly)
1696 {
1697         int ret, i;
1698
1699         if (!obj->active)
1700                 return 0;
1701
1702         if (readonly) {
1703                 if (obj->last_write_req != NULL) {
1704                         ret = i915_wait_request(obj->last_write_req);
1705                         if (ret)
1706                                 return ret;
1707
1708                         i = obj->last_write_req->engine->id;
1709                         if (obj->last_read_req[i] == obj->last_write_req)
1710                                 i915_gem_object_retire__read(obj, i);
1711                         else
1712                                 i915_gem_object_retire__write(obj);
1713                 }
1714         } else {
1715                 for (i = 0; i < I915_NUM_ENGINES; i++) {
1716                         if (obj->last_read_req[i] == NULL)
1717                                 continue;
1718
1719                         ret = i915_wait_request(obj->last_read_req[i]);
1720                         if (ret)
1721                                 return ret;
1722
1723                         i915_gem_object_retire__read(obj, i);
1724                 }
1725                 GEM_BUG_ON(obj->active);
1726         }
1727
1728         return 0;
1729 }
1730
1731 static void
1732 i915_gem_object_retire_request(struct drm_i915_gem_object *obj,
1733                                struct drm_i915_gem_request *req)
1734 {
1735         int ring = req->engine->id;
1736
1737         if (obj->last_read_req[ring] == req)
1738                 i915_gem_object_retire__read(obj, ring);
1739         else if (obj->last_write_req == req)
1740                 i915_gem_object_retire__write(obj);
1741
1742         if (!i915_reset_in_progress(&req->i915->gpu_error))
1743                 __i915_gem_request_retire__upto(req);
1744 }
1745
1746 /* A nonblocking variant of the above wait. This is a highly dangerous routine
1747  * as the object state may change during this call.
1748  */
1749 static __must_check int
1750 i915_gem_object_wait_rendering__nonblocking(struct drm_i915_gem_object *obj,
1751                                             struct intel_rps_client *rps,
1752                                             bool readonly)
1753 {
1754         struct drm_device *dev = obj->base.dev;
1755         struct drm_i915_private *dev_priv = to_i915(dev);
1756         struct drm_i915_gem_request *requests[I915_NUM_ENGINES];
1757         int ret, i, n = 0;
1758
1759         BUG_ON(!mutex_is_locked(&dev->struct_mutex));
1760         BUG_ON(!dev_priv->mm.interruptible);
1761
1762         if (!obj->active)
1763                 return 0;
1764
1765         if (readonly) {
1766                 struct drm_i915_gem_request *req;
1767
1768                 req = obj->last_write_req;
1769                 if (req == NULL)
1770                         return 0;
1771
1772                 requests[n++] = i915_gem_request_reference(req);
1773         } else {
1774                 for (i = 0; i < I915_NUM_ENGINES; i++) {
1775                         struct drm_i915_gem_request *req;
1776
1777                         req = obj->last_read_req[i];
1778                         if (req == NULL)
1779                                 continue;
1780
1781                         requests[n++] = i915_gem_request_reference(req);
1782                 }
1783         }
1784
1785         mutex_unlock(&dev->struct_mutex);
1786         ret = 0;
1787         for (i = 0; ret == 0 && i < n; i++)
1788                 ret = __i915_wait_request(requests[i], true, NULL, rps);
1789         mutex_lock(&dev->struct_mutex);
1790
1791         for (i = 0; i < n; i++) {
1792                 if (ret == 0)
1793                         i915_gem_object_retire_request(obj, requests[i]);
1794                 i915_gem_request_unreference(requests[i]);
1795         }
1796
1797         return ret;
1798 }
1799
1800 static struct intel_rps_client *to_rps_client(struct drm_file *file)
1801 {
1802         struct drm_i915_file_private *fpriv = file->driver_priv;
1803         return &fpriv->rps;
1804 }
1805
1806 static enum fb_op_origin
1807 write_origin(struct drm_i915_gem_object *obj, unsigned domain)
1808 {
1809         return domain == I915_GEM_DOMAIN_GTT && !obj->has_wc_mmap ?
1810                ORIGIN_GTT : ORIGIN_CPU;
1811 }
1812
1813 /**
1814  * Called when user space prepares to use an object with the CPU, either
1815  * through the mmap ioctl's mapping or a GTT mapping.
1816  * @dev: drm device
1817  * @data: ioctl data blob
1818  * @file: drm file
1819  */
1820 int
1821 i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
1822                           struct drm_file *file)
1823 {
1824         struct drm_i915_gem_set_domain *args = data;
1825         struct drm_i915_gem_object *obj;
1826         uint32_t read_domains = args->read_domains;
1827         uint32_t write_domain = args->write_domain;
1828         int ret;
1829
1830         /* Only handle setting domains to types used by the CPU. */
1831         if (write_domain & I915_GEM_GPU_DOMAINS)
1832                 return -EINVAL;
1833
1834         if (read_domains & I915_GEM_GPU_DOMAINS)
1835                 return -EINVAL;
1836
1837         /* Having something in the write domain implies it's in the read
1838          * domain, and only that read domain.  Enforce that in the request.
1839          */
1840         if (write_domain != 0 && read_domains != write_domain)
1841                 return -EINVAL;
1842
1843         ret = i915_mutex_lock_interruptible(dev);
1844         if (ret)
1845                 return ret;
1846
1847         obj = to_intel_bo(drm_gem_object_lookup(file, args->handle));
1848         if (&obj->base == NULL) {
1849                 ret = -ENOENT;
1850                 goto unlock;
1851         }
1852
1853         /* Try to flush the object off the GPU without holding the lock.
1854          * We will repeat the flush holding the lock in the normal manner
1855          * to catch cases where we are gazumped.
1856          */
1857         ret = i915_gem_object_wait_rendering__nonblocking(obj,
1858                                                           to_rps_client(file),
1859                                                           !write_domain);
1860         if (ret)
1861                 goto unref;
1862
1863         if (read_domains & I915_GEM_DOMAIN_GTT)
1864                 ret = i915_gem_object_set_to_gtt_domain(obj, write_domain != 0);
1865         else
1866                 ret = i915_gem_object_set_to_cpu_domain(obj, write_domain != 0);
1867
1868         if (write_domain != 0)
1869                 intel_fb_obj_invalidate(obj, write_origin(obj, write_domain));
1870
1871 unref:
1872         drm_gem_object_unreference(&obj->base);
1873 unlock:
1874         mutex_unlock(&dev->struct_mutex);
1875         return ret;
1876 }
1877
1878 /**
1879  * Called when user space has done writes to this buffer
1880  * @dev: drm device
1881  * @data: ioctl data blob
1882  * @file: drm file
1883  */
1884 int
1885 i915_gem_sw_finish_ioctl(struct drm_device *dev, void *data,
1886                          struct drm_file *file)
1887 {
1888         struct drm_i915_gem_sw_finish *args = data;
1889         struct drm_i915_gem_object *obj;
1890         int ret = 0;
1891
1892         ret = i915_mutex_lock_interruptible(dev);
1893         if (ret)
1894                 return ret;
1895
1896         obj = to_intel_bo(drm_gem_object_lookup(file, args->handle));
1897         if (&obj->base == NULL) {
1898                 ret = -ENOENT;
1899                 goto unlock;
1900         }
1901
1902         /* Pinned buffers may be scanout, so flush the cache */
1903         if (obj->pin_display)
1904                 i915_gem_object_flush_cpu_write_domain(obj);
1905
1906         drm_gem_object_unreference(&obj->base);
1907 unlock:
1908         mutex_unlock(&dev->struct_mutex);
1909         return ret;
1910 }
1911
1912 /**
1913  * i915_gem_mmap_ioctl - Maps the contents of an object, returning the address
1914  *                       it is mapped to.
1915  * @dev: drm device
1916  * @data: ioctl data blob
1917  * @file: drm file
1918  *
1919  * While the mapping holds a reference on the contents of the object, it doesn't
1920  * imply a ref on the object itself.
1921  *
1922  * IMPORTANT:
1923  *
1924  * DRM driver writers who look a this function as an example for how to do GEM
1925  * mmap support, please don't implement mmap support like here. The modern way
1926  * to implement DRM mmap support is with an mmap offset ioctl (like
1927  * i915_gem_mmap_gtt) and then using the mmap syscall on the DRM fd directly.
1928  * That way debug tooling like valgrind will understand what's going on, hiding
1929  * the mmap call in a driver private ioctl will break that. The i915 driver only
1930  * does cpu mmaps this way because we didn't know better.
1931  */
1932 int
1933 i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
1934                     struct drm_file *file)
1935 {
1936         struct drm_i915_gem_mmap *args = data;
1937         struct drm_gem_object *obj;
1938         unsigned long addr;
1939
1940         if (args->flags & ~(I915_MMAP_WC))
1941                 return -EINVAL;
1942
1943         if (args->flags & I915_MMAP_WC && !boot_cpu_has(X86_FEATURE_PAT))
1944                 return -ENODEV;
1945
1946         obj = drm_gem_object_lookup(file, args->handle);
1947         if (obj == NULL)
1948                 return -ENOENT;
1949
1950         /* prime objects have no backing filp to GEM mmap
1951          * pages from.
1952          */
1953         if (!obj->filp) {
1954                 drm_gem_object_unreference_unlocked(obj);
1955                 return -EINVAL;
1956         }
1957
1958         addr = vm_mmap(obj->filp, 0, args->size,
1959                        PROT_READ | PROT_WRITE, MAP_SHARED,
1960                        args->offset);
1961         if (args->flags & I915_MMAP_WC) {
1962                 struct mm_struct *mm = current->mm;
1963                 struct vm_area_struct *vma;
1964
1965                 if (down_write_killable(&mm->mmap_sem)) {
1966                         drm_gem_object_unreference_unlocked(obj);
1967                         return -EINTR;
1968                 }
1969                 vma = find_vma(mm, addr);
1970                 if (vma)
1971                         vma->vm_page_prot =
1972                                 pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
1973                 else
1974                         addr = -ENOMEM;
1975                 up_write(&mm->mmap_sem);
1976
1977                 /* This may race, but that's ok, it only gets set */
1978                 WRITE_ONCE(to_intel_bo(obj)->has_wc_mmap, true);
1979         }
1980         drm_gem_object_unreference_unlocked(obj);
1981         if (IS_ERR((void *)addr))
1982                 return addr;
1983
1984         args->addr_ptr = (uint64_t) addr;
1985
1986         return 0;
1987 }
1988
1989 /**
1990  * i915_gem_fault - fault a page into the GTT
1991  * @vma: VMA in question
1992  * @vmf: fault info
1993  *
1994  * The fault handler is set up by drm_gem_mmap() when a object is GTT mapped
1995  * from userspace.  The fault handler takes care of binding the object to
1996  * the GTT (if needed), allocating and programming a fence register (again,
1997  * only if needed based on whether the old reg is still valid or the object
1998  * is tiled) and inserting a new PTE into the faulting process.
1999  *
2000  * Note that the faulting process may involve evicting existing objects
2001  * from the GTT and/or fence registers to make room.  So performance may
2002  * suffer if the GTT working set is large or there are few fence registers
2003  * left.
2004  */
2005 int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2006 {
2007         struct drm_i915_gem_object *obj = to_intel_bo(vma->vm_private_data);
2008         struct drm_device *dev = obj->base.dev;
2009         struct drm_i915_private *dev_priv = to_i915(dev);
2010         struct i915_ggtt *ggtt = &dev_priv->ggtt;
2011         struct i915_ggtt_view view = i915_ggtt_view_normal;
2012         pgoff_t page_offset;
2013         unsigned long pfn;
2014         int ret = 0;
2015         bool write = !!(vmf->flags & FAULT_FLAG_WRITE);
2016
2017         intel_runtime_pm_get(dev_priv);
2018
2019         /* We don't use vmf->pgoff since that has the fake offset */
2020         page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
2021                 PAGE_SHIFT;
2022
2023         ret = i915_mutex_lock_interruptible(dev);
2024         if (ret)
2025                 goto out;
2026
2027         trace_i915_gem_object_fault(obj, page_offset, true, write);
2028
2029         /* Try to flush the object off the GPU first without holding the lock.
2030          * Upon reacquiring the lock, we will perform our sanity checks and then
2031          * repeat the flush holding the lock in the normal manner to catch cases
2032          * where we are gazumped.
2033          */
2034         ret = i915_gem_object_wait_rendering__nonblocking(obj, NULL, !write);
2035         if (ret)
2036                 goto unlock;
2037
2038         /* Access to snoopable pages through the GTT is incoherent. */
2039         if (obj->cache_level != I915_CACHE_NONE && !HAS_LLC(dev)) {
2040                 ret = -EFAULT;
2041                 goto unlock;
2042         }
2043
2044         /* Use a partial view if the object is bigger than the aperture. */
2045         if (obj->base.size >= ggtt->mappable_end &&
2046             obj->tiling_mode == I915_TILING_NONE) {
2047                 static const unsigned int chunk_size = 256; // 1 MiB
2048
2049                 memset(&view, 0, sizeof(view));
2050                 view.type = I915_GGTT_VIEW_PARTIAL;
2051                 view.params.partial.offset = rounddown(page_offset, chunk_size);
2052                 view.params.partial.size =
2053                         min_t(unsigned int,
2054                               chunk_size,
2055                               (vma->vm_end - vma->vm_start)/PAGE_SIZE -
2056                               view.params.partial.offset);
2057         }
2058
2059         /* Now pin it into the GTT if needed */
2060         ret = i915_gem_object_ggtt_pin(obj, &view, 0, PIN_MAPPABLE);
2061         if (ret)
2062                 goto unlock;
2063
2064         ret = i915_gem_object_set_to_gtt_domain(obj, write);
2065         if (ret)
2066                 goto unpin;
2067
2068         ret = i915_gem_object_get_fence(obj);
2069         if (ret)
2070                 goto unpin;
2071
2072         /* Finally, remap it using the new GTT offset */
2073         pfn = ggtt->mappable_base +
2074                 i915_gem_obj_ggtt_offset_view(obj, &view);
2075         pfn >>= PAGE_SHIFT;
2076
2077         if (unlikely(view.type == I915_GGTT_VIEW_PARTIAL)) {
2078                 /* Overriding existing pages in partial view does not cause
2079                  * us any trouble as TLBs are still valid because the fault
2080                  * is due to userspace losing part of the mapping or never
2081                  * having accessed it before (at this partials' range).
2082                  */
2083                 unsigned long base = vma->vm_start +
2084                                      (view.params.partial.offset << PAGE_SHIFT);
2085                 unsigned int i;
2086
2087                 for (i = 0; i < view.params.partial.size; i++) {
2088                         ret = vm_insert_pfn(vma, base + i * PAGE_SIZE, pfn + i);
2089                         if (ret)
2090                                 break;
2091                 }
2092
2093                 obj->fault_mappable = true;
2094         } else {
2095                 if (!obj->fault_mappable) {
2096                         unsigned long size = min_t(unsigned long,
2097                                                    vma->vm_end - vma->vm_start,
2098                                                    obj->base.size);
2099                         int i;
2100
2101                         for (i = 0; i < size >> PAGE_SHIFT; i++) {
2102                                 ret = vm_insert_pfn(vma,
2103                                                     (unsigned long)vma->vm_start + i * PAGE_SIZE,
2104                                                     pfn + i);
2105                                 if (ret)
2106                                         break;
2107                         }
2108
2109                         obj->fault_mappable = true;
2110                 } else
2111                         ret = vm_insert_pfn(vma,
2112                                             (unsigned long)vmf->virtual_address,
2113                                             pfn + page_offset);
2114         }
2115 unpin:
2116         i915_gem_object_ggtt_unpin_view(obj, &view);
2117 unlock:
2118         mutex_unlock(&dev->struct_mutex);
2119 out:
2120         switch (ret) {
2121         case -EIO:
2122                 /*
2123                  * We eat errors when the gpu is terminally wedged to avoid
2124                  * userspace unduly crashing (gl has no provisions for mmaps to
2125                  * fail). But any other -EIO isn't ours (e.g. swap in failure)
2126                  * and so needs to be reported.
2127                  */
2128                 if (!i915_terminally_wedged(&dev_priv->gpu_error)) {
2129                         ret = VM_FAULT_SIGBUS;
2130                         break;
2131                 }
2132         case -EAGAIN:
2133                 /*
2134                  * EAGAIN means the gpu is hung and we'll wait for the error
2135                  * handler to reset everything when re-faulting in
2136                  * i915_mutex_lock_interruptible.
2137                  */
2138         case 0:
2139         case -ERESTARTSYS:
2140         case -EINTR:
2141         case -EBUSY:
2142                 /*
2143                  * EBUSY is ok: this just means that another thread
2144                  * already did the job.
2145                  */
2146                 ret = VM_FAULT_NOPAGE;
2147                 break;
2148         case -ENOMEM:
2149                 ret = VM_FAULT_OOM;
2150                 break;
2151         case -ENOSPC:
2152         case -EFAULT:
2153                 ret = VM_FAULT_SIGBUS;
2154                 break;
2155         default:
2156                 WARN_ONCE(ret, "unhandled error in i915_gem_fault: %i\n", ret);
2157                 ret = VM_FAULT_SIGBUS;
2158                 break;
2159         }
2160
2161         intel_runtime_pm_put(dev_priv);
2162         return ret;
2163 }
2164
2165 /**
2166  * i915_gem_release_mmap - remove physical page mappings
2167  * @obj: obj in question
2168  *
2169  * Preserve the reservation of the mmapping with the DRM core code, but
2170  * relinquish ownership of the pages back to the system.
2171  *
2172  * It is vital that we remove the page mapping if we have mapped a tiled
2173  * object through the GTT and then lose the fence register due to
2174  * resource pressure. Similarly if the object has been moved out of the
2175  * aperture, than pages mapped into userspace must be revoked. Removing the
2176  * mapping will then trigger a page fault on the next user access, allowing
2177  * fixup by i915_gem_fault().
2178  */
2179 void
2180 i915_gem_release_mmap(struct drm_i915_gem_object *obj)
2181 {
2182         /* Serialisation between user GTT access and our code depends upon
2183          * revoking the CPU's PTE whilst the mutex is held. The next user
2184          * pagefault then has to wait until we release the mutex.
2185          */
2186         lockdep_assert_held(&obj->base.dev->struct_mutex);
2187
2188         if (!obj->fault_mappable)
2189                 return;
2190
2191         drm_vma_node_unmap(&obj->base.vma_node,
2192                            obj->base.dev->anon_inode->i_mapping);
2193
2194         /* Ensure that the CPU's PTE are revoked and there are not outstanding
2195          * memory transactions from userspace before we return. The TLB
2196          * flushing implied above by changing the PTE above *should* be
2197          * sufficient, an extra barrier here just provides us with a bit
2198          * of paranoid documentation about our requirement to serialise
2199          * memory writes before touching registers / GSM.
2200          */
2201         wmb();
2202
2203         obj->fault_mappable = false;
2204 }
2205
2206 void
2207 i915_gem_release_all_mmaps(struct drm_i915_private *dev_priv)
2208 {
2209         struct drm_i915_gem_object *obj;
2210
2211         list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list)
2212                 i915_gem_release_mmap(obj);
2213 }
2214
2215 uint32_t
2216 i915_gem_get_gtt_size(struct drm_device *dev, uint32_t size, int tiling_mode)
2217 {
2218         uint32_t gtt_size;
2219
2220         if (INTEL_INFO(dev)->gen >= 4 ||
2221             tiling_mode == I915_TILING_NONE)
2222                 return size;
2223
2224         /* Previous chips need a power-of-two fence region when tiling */
2225         if (IS_GEN3(dev))
2226                 gtt_size = 1024*1024;
2227         else
2228                 gtt_size = 512*1024;
2229
2230         while (gtt_size < size)
2231                 gtt_size <<= 1;
2232
2233         return gtt_size;
2234 }
2235
2236 /**
2237  * i915_gem_get_gtt_alignment - return required GTT alignment for an object
2238  * @dev: drm device
2239  * @size: object size
2240  * @tiling_mode: tiling mode
2241  * @fenced: is fenced alignemned required or not
2242  *
2243  * Return the required GTT alignment for an object, taking into account
2244  * potential fence register mapping.
2245  */
2246 uint32_t
2247 i915_gem_get_gtt_alignment(struct drm_device *dev, uint32_t size,
2248                            int tiling_mode, bool fenced)
2249 {
2250         /*
2251          * Minimum alignment is 4k (GTT page size), but might be greater
2252          * if a fence register is needed for the object.
2253          */
2254         if (INTEL_INFO(dev)->gen >= 4 || (!fenced && IS_G33(dev)) ||
2255             tiling_mode == I915_TILING_NONE)
2256                 return 4096;
2257
2258         /*
2259          * Previous chips need to be aligned to the size of the smallest
2260          * fence register that can contain the object.
2261          */
2262         return i915_gem_get_gtt_size(dev, size, tiling_mode);
2263 }
2264
2265 static int i915_gem_object_create_mmap_offset(struct drm_i915_gem_object *obj)
2266 {
2267         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
2268         int ret;
2269
2270         dev_priv->mm.shrinker_no_lock_stealing = true;
2271
2272         ret = drm_gem_create_mmap_offset(&obj->base);
2273         if (ret != -ENOSPC)
2274                 goto out;
2275
2276         /* Badly fragmented mmap space? The only way we can recover
2277          * space is by destroying unwanted objects. We can't randomly release
2278          * mmap_offsets as userspace expects them to be persistent for the
2279          * lifetime of the objects. The closest we can is to release the
2280          * offsets on purgeable objects by truncating it and marking it purged,
2281          * which prevents userspace from ever using that object again.
2282          */
2283         i915_gem_shrink(dev_priv,
2284                         obj->base.size >> PAGE_SHIFT,
2285                         I915_SHRINK_BOUND |
2286                         I915_SHRINK_UNBOUND |
2287                         I915_SHRINK_PURGEABLE);
2288         ret = drm_gem_create_mmap_offset(&obj->base);
2289         if (ret != -ENOSPC)
2290                 goto out;
2291
2292         i915_gem_shrink_all(dev_priv);
2293         ret = drm_gem_create_mmap_offset(&obj->base);
2294 out:
2295         dev_priv->mm.shrinker_no_lock_stealing = false;
2296
2297         return ret;
2298 }
2299
2300 static void i915_gem_object_free_mmap_offset(struct drm_i915_gem_object *obj)
2301 {
2302         drm_gem_free_mmap_offset(&obj->base);
2303 }
2304
2305 int
2306 i915_gem_mmap_gtt(struct drm_file *file,
2307                   struct drm_device *dev,
2308                   uint32_t handle,
2309                   uint64_t *offset)
2310 {
2311         struct drm_i915_gem_object *obj;
2312         int ret;
2313
2314         ret = i915_mutex_lock_interruptible(dev);
2315         if (ret)
2316                 return ret;
2317
2318         obj = to_intel_bo(drm_gem_object_lookup(file, handle));
2319         if (&obj->base == NULL) {
2320                 ret = -ENOENT;
2321                 goto unlock;
2322         }
2323
2324         if (obj->madv != I915_MADV_WILLNEED) {
2325                 DRM_DEBUG("Attempting to mmap a purgeable buffer\n");
2326                 ret = -EFAULT;
2327                 goto out;
2328         }
2329
2330         ret = i915_gem_object_create_mmap_offset(obj);
2331         if (ret)
2332                 goto out;
2333
2334         *offset = drm_vma_node_offset_addr(&obj->base.vma_node);
2335
2336 out:
2337         drm_gem_object_unreference(&obj->base);
2338 unlock:
2339         mutex_unlock(&dev->struct_mutex);
2340         return ret;
2341 }
2342
2343 /**
2344  * i915_gem_mmap_gtt_ioctl - prepare an object for GTT mmap'ing
2345  * @dev: DRM device
2346  * @data: GTT mapping ioctl data
2347  * @file: GEM object info
2348  *
2349  * Simply returns the fake offset to userspace so it can mmap it.
2350  * The mmap call will end up in drm_gem_mmap(), which will set things
2351  * up so we can get faults in the handler above.
2352  *
2353  * The fault handler will take care of binding the object into the GTT
2354  * (since it may have been evicted to make room for something), allocating
2355  * a fence register, and mapping the appropriate aperture address into
2356  * userspace.
2357  */
2358 int
2359 i915_gem_mmap_gtt_ioctl(struct drm_device *dev, void *data,
2360                         struct drm_file *file)
2361 {
2362         struct drm_i915_gem_mmap_gtt *args = data;
2363
2364         return i915_gem_mmap_gtt(file, dev, args->handle, &args->offset);
2365 }
2366
2367 /* Immediately discard the backing storage */
2368 static void
2369 i915_gem_object_truncate(struct drm_i915_gem_object *obj)
2370 {
2371         i915_gem_object_free_mmap_offset(obj);
2372
2373         if (obj->base.filp == NULL)
2374                 return;
2375
2376         /* Our goal here is to return as much of the memory as
2377          * is possible back to the system as we are called from OOM.
2378          * To do this we must instruct the shmfs to drop all of its
2379          * backing pages, *now*.
2380          */
2381         shmem_truncate_range(file_inode(obj->base.filp), 0, (loff_t)-1);
2382         obj->madv = __I915_MADV_PURGED;
2383 }
2384
2385 /* Try to discard unwanted pages */
2386 static void
2387 i915_gem_object_invalidate(struct drm_i915_gem_object *obj)
2388 {
2389         struct address_space *mapping;
2390
2391         switch (obj->madv) {
2392         case I915_MADV_DONTNEED:
2393                 i915_gem_object_truncate(obj);
2394         case __I915_MADV_PURGED:
2395                 return;
2396         }
2397
2398         if (obj->base.filp == NULL)
2399                 return;
2400
2401         mapping = obj->base.filp->f_mapping,
2402         invalidate_mapping_pages(mapping, 0, (loff_t)-1);
2403 }
2404
2405 static void
2406 i915_gem_object_put_pages_gtt(struct drm_i915_gem_object *obj)
2407 {
2408         struct sgt_iter sgt_iter;
2409         struct page *page;
2410         int ret;
2411
2412         BUG_ON(obj->madv == __I915_MADV_PURGED);
2413
2414         ret = i915_gem_object_set_to_cpu_domain(obj, true);
2415         if (WARN_ON(ret)) {
2416                 /* In the event of a disaster, abandon all caches and
2417                  * hope for the best.
2418                  */
2419                 i915_gem_clflush_object(obj, true);
2420                 obj->base.read_domains = obj->base.write_domain = I915_GEM_DOMAIN_CPU;
2421         }
2422
2423         i915_gem_gtt_finish_object(obj);
2424
2425         if (i915_gem_object_needs_bit17_swizzle(obj))
2426                 i915_gem_object_save_bit_17_swizzle(obj);
2427
2428         if (obj->madv == I915_MADV_DONTNEED)
2429                 obj->dirty = 0;
2430
2431         for_each_sgt_page(page, sgt_iter, obj->pages) {
2432                 if (obj->dirty)
2433                         set_page_dirty(page);
2434
2435                 if (obj->madv == I915_MADV_WILLNEED)
2436                         mark_page_accessed(page);
2437
2438                 put_page(page);
2439         }
2440         obj->dirty = 0;
2441
2442         sg_free_table(obj->pages);
2443         kfree(obj->pages);
2444 }
2445
2446 int
2447 i915_gem_object_put_pages(struct drm_i915_gem_object *obj)
2448 {
2449         const struct drm_i915_gem_object_ops *ops = obj->ops;
2450
2451         if (obj->pages == NULL)
2452                 return 0;
2453
2454         if (obj->pages_pin_count)
2455                 return -EBUSY;
2456
2457         BUG_ON(i915_gem_obj_bound_any(obj));
2458
2459         /* ->put_pages might need to allocate memory for the bit17 swizzle
2460          * array, hence protect them from being reaped by removing them from gtt
2461          * lists early. */
2462         list_del(&obj->global_list);
2463
2464         if (obj->mapping) {
2465                 if (is_vmalloc_addr(obj->mapping))
2466                         vunmap(obj->mapping);
2467                 else
2468                         kunmap(kmap_to_page(obj->mapping));
2469                 obj->mapping = NULL;
2470         }
2471
2472         ops->put_pages(obj);
2473         obj->pages = NULL;
2474
2475         i915_gem_object_invalidate(obj);
2476
2477         return 0;
2478 }
2479
2480 static int
2481 i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
2482 {
2483         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
2484         int page_count, i;
2485         struct address_space *mapping;
2486         struct sg_table *st;
2487         struct scatterlist *sg;
2488         struct sgt_iter sgt_iter;
2489         struct page *page;
2490         unsigned long last_pfn = 0;     /* suppress gcc warning */
2491         int ret;
2492         gfp_t gfp;
2493
2494         /* Assert that the object is not currently in any GPU domain. As it
2495          * wasn't in the GTT, there shouldn't be any way it could have been in
2496          * a GPU cache
2497          */
2498         BUG_ON(obj->base.read_domains & I915_GEM_GPU_DOMAINS);
2499         BUG_ON(obj->base.write_domain & I915_GEM_GPU_DOMAINS);
2500
2501         st = kmalloc(sizeof(*st), GFP_KERNEL);
2502         if (st == NULL)
2503                 return -ENOMEM;
2504
2505         page_count = obj->base.size / PAGE_SIZE;
2506         if (sg_alloc_table(st, page_count, GFP_KERNEL)) {
2507                 kfree(st);
2508                 return -ENOMEM;
2509         }
2510
2511         /* Get the list of pages out of our struct file.  They'll be pinned
2512          * at this point until we release them.
2513          *
2514          * Fail silently without starting the shrinker
2515          */
2516         mapping = obj->base.filp->f_mapping;
2517         gfp = mapping_gfp_constraint(mapping, ~(__GFP_IO | __GFP_RECLAIM));
2518         gfp |= __GFP_NORETRY | __GFP_NOWARN;
2519         sg = st->sgl;
2520         st->nents = 0;
2521         for (i = 0; i < page_count; i++) {
2522                 page = shmem_read_mapping_page_gfp(mapping, i, gfp);
2523                 if (IS_ERR(page)) {
2524                         i915_gem_shrink(dev_priv,
2525                                         page_count,
2526                                         I915_SHRINK_BOUND |
2527                                         I915_SHRINK_UNBOUND |
2528                                         I915_SHRINK_PURGEABLE);
2529                         page = shmem_read_mapping_page_gfp(mapping, i, gfp);
2530                 }
2531                 if (IS_ERR(page)) {
2532                         /* We've tried hard to allocate the memory by reaping
2533                          * our own buffer, now let the real VM do its job and
2534                          * go down in flames if truly OOM.
2535                          */
2536                         i915_gem_shrink_all(dev_priv);
2537                         page = shmem_read_mapping_page(mapping, i);
2538                         if (IS_ERR(page)) {
2539                                 ret = PTR_ERR(page);
2540                                 goto err_pages;
2541                         }
2542                 }
2543 #ifdef CONFIG_SWIOTLB
2544                 if (swiotlb_nr_tbl()) {
2545                         st->nents++;
2546                         sg_set_page(sg, page, PAGE_SIZE, 0);
2547                         sg = sg_next(sg);
2548                         continue;
2549                 }
2550 #endif
2551                 if (!i || page_to_pfn(page) != last_pfn + 1) {
2552                         if (i)
2553                                 sg = sg_next(sg);
2554                         st->nents++;
2555                         sg_set_page(sg, page, PAGE_SIZE, 0);
2556                 } else {
2557                         sg->length += PAGE_SIZE;
2558                 }
2559                 last_pfn = page_to_pfn(page);
2560
2561                 /* Check that the i965g/gm workaround works. */
2562                 WARN_ON((gfp & __GFP_DMA32) && (last_pfn >= 0x00100000UL));
2563         }
2564 #ifdef CONFIG_SWIOTLB
2565         if (!swiotlb_nr_tbl())
2566 #endif
2567                 sg_mark_end(sg);
2568         obj->pages = st;
2569
2570         ret = i915_gem_gtt_prepare_object(obj);
2571         if (ret)
2572                 goto err_pages;
2573
2574         if (i915_gem_object_needs_bit17_swizzle(obj))
2575                 i915_gem_object_do_bit_17_swizzle(obj);
2576
2577         if (obj->tiling_mode != I915_TILING_NONE &&
2578             dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES)
2579                 i915_gem_object_pin_pages(obj);
2580
2581         return 0;
2582
2583 err_pages:
2584         sg_mark_end(sg);
2585         for_each_sgt_page(page, sgt_iter, st)
2586                 put_page(page);
2587         sg_free_table(st);
2588         kfree(st);
2589
2590         /* shmemfs first checks if there is enough memory to allocate the page
2591          * and reports ENOSPC should there be insufficient, along with the usual
2592          * ENOMEM for a genuine allocation failure.
2593          *
2594          * We use ENOSPC in our driver to mean that we have run out of aperture
2595          * space and so want to translate the error from shmemfs back to our
2596          * usual understanding of ENOMEM.
2597          */
2598         if (ret == -ENOSPC)
2599                 ret = -ENOMEM;
2600
2601         return ret;
2602 }
2603
2604 /* Ensure that the associated pages are gathered from the backing storage
2605  * and pinned into our object. i915_gem_object_get_pages() may be called
2606  * multiple times before they are released by a single call to
2607  * i915_gem_object_put_pages() - once the pages are no longer referenced
2608  * either as a result of memory pressure (reaping pages under the shrinker)
2609  * or as the object is itself released.
2610  */
2611 int
2612 i915_gem_object_get_pages(struct drm_i915_gem_object *obj)
2613 {
2614         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
2615         const struct drm_i915_gem_object_ops *ops = obj->ops;
2616         int ret;
2617
2618         if (obj->pages)
2619                 return 0;
2620
2621         if (obj->madv != I915_MADV_WILLNEED) {
2622                 DRM_DEBUG("Attempting to obtain a purgeable object\n");
2623                 return -EFAULT;
2624         }
2625
2626         BUG_ON(obj->pages_pin_count);
2627
2628         ret = ops->get_pages(obj);
2629         if (ret)
2630                 return ret;
2631
2632         list_add_tail(&obj->global_list, &dev_priv->mm.unbound_list);
2633
2634         obj->get_page.sg = obj->pages->sgl;
2635         obj->get_page.last = 0;
2636
2637         return 0;
2638 }
2639
2640 /* The 'mapping' part of i915_gem_object_pin_map() below */
2641 static void *i915_gem_object_map(const struct drm_i915_gem_object *obj)
2642 {
2643         unsigned long n_pages = obj->base.size >> PAGE_SHIFT;
2644         struct sg_table *sgt = obj->pages;
2645         struct sgt_iter sgt_iter;
2646         struct page *page;
2647         struct page *stack_pages[32];
2648         struct page **pages = stack_pages;
2649         unsigned long i = 0;
2650         void *addr;
2651
2652         /* A single page can always be kmapped */
2653         if (n_pages == 1)
2654                 return kmap(sg_page(sgt->sgl));
2655
2656         if (n_pages > ARRAY_SIZE(stack_pages)) {
2657                 /* Too big for stack -- allocate temporary array instead */
2658                 pages = drm_malloc_gfp(n_pages, sizeof(*pages), GFP_TEMPORARY);
2659                 if (!pages)
2660                         return NULL;
2661         }
2662
2663         for_each_sgt_page(page, sgt_iter, sgt)
2664                 pages[i++] = page;
2665
2666         /* Check that we have the expected number of pages */
2667         GEM_BUG_ON(i != n_pages);
2668
2669         addr = vmap(pages, n_pages, 0, PAGE_KERNEL);
2670
2671         if (pages != stack_pages)
2672                 drm_free_large(pages);
2673
2674         return addr;
2675 }
2676
2677 /* get, pin, and map the pages of the object into kernel space */
2678 void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj)
2679 {
2680         int ret;
2681
2682         lockdep_assert_held(&obj->base.dev->struct_mutex);
2683
2684         ret = i915_gem_object_get_pages(obj);
2685         if (ret)
2686                 return ERR_PTR(ret);
2687
2688         i915_gem_object_pin_pages(obj);
2689
2690         if (!obj->mapping) {
2691                 obj->mapping = i915_gem_object_map(obj);
2692                 if (!obj->mapping) {
2693                         i915_gem_object_unpin_pages(obj);
2694                         return ERR_PTR(-ENOMEM);
2695                 }
2696         }
2697
2698         return obj->mapping;
2699 }
2700
2701 void i915_vma_move_to_active(struct i915_vma *vma,
2702                              struct drm_i915_gem_request *req)
2703 {
2704         struct drm_i915_gem_object *obj = vma->obj;
2705         struct intel_engine_cs *engine;
2706
2707         engine = i915_gem_request_get_engine(req);
2708
2709         /* Add a reference if we're newly entering the active list. */
2710         if (obj->active == 0)
2711                 drm_gem_object_reference(&obj->base);
2712         obj->active |= intel_engine_flag(engine);
2713
2714         list_move_tail(&obj->engine_list[engine->id], &engine->active_list);
2715         i915_gem_request_assign(&obj->last_read_req[engine->id], req);
2716
2717         list_move_tail(&vma->vm_link, &vma->vm->active_list);
2718 }
2719
2720 static void
2721 i915_gem_object_retire__write(struct drm_i915_gem_object *obj)
2722 {
2723         GEM_BUG_ON(obj->last_write_req == NULL);
2724         GEM_BUG_ON(!(obj->active & intel_engine_flag(obj->last_write_req->engine)));
2725
2726         i915_gem_request_assign(&obj->last_write_req, NULL);
2727         intel_fb_obj_flush(obj, true, ORIGIN_CS);
2728 }
2729
2730 static void
2731 i915_gem_object_retire__read(struct drm_i915_gem_object *obj, int ring)
2732 {
2733         struct i915_vma *vma;
2734
2735         GEM_BUG_ON(obj->last_read_req[ring] == NULL);
2736         GEM_BUG_ON(!(obj->active & (1 << ring)));
2737
2738         list_del_init(&obj->engine_list[ring]);
2739         i915_gem_request_assign(&obj->last_read_req[ring], NULL);
2740
2741         if (obj->last_write_req && obj->last_write_req->engine->id == ring)
2742                 i915_gem_object_retire__write(obj);
2743
2744         obj->active &= ~(1 << ring);
2745         if (obj->active)
2746                 return;
2747
2748         /* Bump our place on the bound list to keep it roughly in LRU order
2749          * so that we don't steal from recently used but inactive objects
2750          * (unless we are forced to ofc!)
2751          */
2752         list_move_tail(&obj->global_list,
2753                        &to_i915(obj->base.dev)->mm.bound_list);
2754
2755         list_for_each_entry(vma, &obj->vma_list, obj_link) {
2756                 if (!list_empty(&vma->vm_link))
2757                         list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
2758         }
2759
2760         i915_gem_request_assign(&obj->last_fenced_req, NULL);
2761         drm_gem_object_unreference(&obj->base);
2762 }
2763
2764 static int
2765 i915_gem_init_seqno(struct drm_i915_private *dev_priv, u32 seqno)
2766 {
2767         struct intel_engine_cs *engine;
2768         int ret;
2769
2770         /* Carefully retire all requests without writing to the rings */
2771         for_each_engine(engine, dev_priv) {
2772                 ret = intel_engine_idle(engine);
2773                 if (ret)
2774                         return ret;
2775         }
2776         i915_gem_retire_requests(dev_priv);
2777
2778         /* If the seqno wraps around, we need to clear the breadcrumb rbtree */
2779         if (!i915_seqno_passed(seqno, dev_priv->next_seqno)) {
2780                 while (intel_kick_waiters(dev_priv) ||
2781                        intel_kick_signalers(dev_priv))
2782                         yield();
2783         }
2784
2785         /* Finally reset hw state */
2786         for_each_engine(engine, dev_priv)
2787                 intel_ring_init_seqno(engine, seqno);
2788
2789         return 0;
2790 }
2791
2792 int i915_gem_set_seqno(struct drm_device *dev, u32 seqno)
2793 {
2794         struct drm_i915_private *dev_priv = to_i915(dev);
2795         int ret;
2796
2797         if (seqno == 0)
2798                 return -EINVAL;
2799
2800         /* HWS page needs to be set less than what we
2801          * will inject to ring
2802          */
2803         ret = i915_gem_init_seqno(dev_priv, seqno - 1);
2804         if (ret)
2805                 return ret;
2806
2807         /* Carefully set the last_seqno value so that wrap
2808          * detection still works
2809          */
2810         dev_priv->next_seqno = seqno;
2811         dev_priv->last_seqno = seqno - 1;
2812         if (dev_priv->last_seqno == 0)
2813                 dev_priv->last_seqno--;
2814
2815         return 0;
2816 }
2817
2818 int
2819 i915_gem_get_seqno(struct drm_i915_private *dev_priv, u32 *seqno)
2820 {
2821         /* reserve 0 for non-seqno */
2822         if (dev_priv->next_seqno == 0) {
2823                 int ret = i915_gem_init_seqno(dev_priv, 0);
2824                 if (ret)
2825                         return ret;
2826
2827                 dev_priv->next_seqno = 1;
2828         }
2829
2830         *seqno = dev_priv->last_seqno = dev_priv->next_seqno++;
2831         return 0;
2832 }
2833
2834 static void i915_gem_mark_busy(const struct intel_engine_cs *engine)
2835 {
2836         struct drm_i915_private *dev_priv = engine->i915;
2837
2838         dev_priv->gt.active_engines |= intel_engine_flag(engine);
2839         if (dev_priv->gt.awake)
2840                 return;
2841
2842         intel_runtime_pm_get_noresume(dev_priv);
2843         dev_priv->gt.awake = true;
2844
2845         i915_update_gfx_val(dev_priv);
2846         if (INTEL_GEN(dev_priv) >= 6)
2847                 gen6_rps_busy(dev_priv);
2848
2849         queue_delayed_work(dev_priv->wq,
2850                            &dev_priv->gt.retire_work,
2851                            round_jiffies_up_relative(HZ));
2852 }
2853
2854 /*
2855  * NB: This function is not allowed to fail. Doing so would mean the the
2856  * request is not being tracked for completion but the work itself is
2857  * going to happen on the hardware. This would be a Bad Thing(tm).
2858  */
2859 void __i915_add_request(struct drm_i915_gem_request *request,
2860                         struct drm_i915_gem_object *obj,
2861                         bool flush_caches)
2862 {
2863         struct intel_engine_cs *engine;
2864         struct intel_ringbuffer *ringbuf;
2865         u32 request_start;
2866         u32 reserved_tail;
2867         int ret;
2868
2869         if (WARN_ON(request == NULL))
2870                 return;
2871
2872         engine = request->engine;
2873         ringbuf = request->ringbuf;
2874
2875         /*
2876          * To ensure that this call will not fail, space for its emissions
2877          * should already have been reserved in the ring buffer. Let the ring
2878          * know that it is time to use that space up.
2879          */
2880         request_start = intel_ring_get_tail(ringbuf);
2881         reserved_tail = request->reserved_space;
2882         request->reserved_space = 0;
2883
2884         /*
2885          * Emit any outstanding flushes - execbuf can fail to emit the flush
2886          * after having emitted the batchbuffer command. Hence we need to fix
2887          * things up similar to emitting the lazy request. The difference here
2888          * is that the flush _must_ happen before the next request, no matter
2889          * what.
2890          */
2891         if (flush_caches) {
2892                 if (i915.enable_execlists)
2893                         ret = logical_ring_flush_all_caches(request);
2894                 else
2895                         ret = intel_ring_flush_all_caches(request);
2896                 /* Not allowed to fail! */
2897                 WARN(ret, "*_ring_flush_all_caches failed: %d!\n", ret);
2898         }
2899
2900         trace_i915_gem_request_add(request);
2901
2902         request->head = request_start;
2903
2904         /* Whilst this request exists, batch_obj will be on the
2905          * active_list, and so will hold the active reference. Only when this
2906          * request is retired will the the batch_obj be moved onto the
2907          * inactive_list and lose its active reference. Hence we do not need
2908          * to explicitly hold another reference here.
2909          */
2910         request->batch_obj = obj;
2911
2912         /* Seal the request and mark it as pending execution. Note that
2913          * we may inspect this state, without holding any locks, during
2914          * hangcheck. Hence we apply the barrier to ensure that we do not
2915          * see a more recent value in the hws than we are tracking.
2916          */
2917         request->emitted_jiffies = jiffies;
2918         request->previous_seqno = engine->last_submitted_seqno;
2919         smp_store_mb(engine->last_submitted_seqno, request->seqno);
2920         list_add_tail(&request->list, &engine->request_list);
2921
2922         /* Record the position of the start of the request so that
2923          * should we detect the updated seqno part-way through the
2924          * GPU processing the request, we never over-estimate the
2925          * position of the head.
2926          */
2927         request->postfix = intel_ring_get_tail(ringbuf);
2928
2929         if (i915.enable_execlists)
2930                 ret = engine->emit_request(request);
2931         else {
2932                 ret = engine->add_request(request);
2933
2934                 request->tail = intel_ring_get_tail(ringbuf);
2935         }
2936         /* Not allowed to fail! */
2937         WARN(ret, "emit|add_request failed: %d!\n", ret);
2938         /* Sanity check that the reserved size was large enough. */
2939         ret = intel_ring_get_tail(ringbuf) - request_start;
2940         if (ret < 0)
2941                 ret += ringbuf->size;
2942         WARN_ONCE(ret > reserved_tail,
2943                   "Not enough space reserved (%d bytes) "
2944                   "for adding the request (%d bytes)\n",
2945                   reserved_tail, ret);
2946
2947         i915_gem_mark_busy(engine);
2948 }
2949
2950 static bool i915_context_is_banned(const struct i915_gem_context *ctx)
2951 {
2952         unsigned long elapsed;
2953
2954         if (ctx->hang_stats.banned)
2955                 return true;
2956
2957         elapsed = get_seconds() - ctx->hang_stats.guilty_ts;
2958         if (ctx->hang_stats.ban_period_seconds &&
2959             elapsed <= ctx->hang_stats.ban_period_seconds) {
2960                 DRM_DEBUG("context hanging too fast, banning!\n");
2961                 return true;
2962         }
2963
2964         return false;
2965 }
2966
2967 static void i915_set_reset_status(struct i915_gem_context *ctx,
2968                                   const bool guilty)
2969 {
2970         struct i915_ctx_hang_stats *hs = &ctx->hang_stats;
2971
2972         if (guilty) {
2973                 hs->banned = i915_context_is_banned(ctx);
2974                 hs->batch_active++;
2975                 hs->guilty_ts = get_seconds();
2976         } else {
2977                 hs->batch_pending++;
2978         }
2979 }
2980
2981 void i915_gem_request_free(struct kref *req_ref)
2982 {
2983         struct drm_i915_gem_request *req = container_of(req_ref,
2984                                                  typeof(*req), ref);
2985         kmem_cache_free(req->i915->requests, req);
2986 }
2987
2988 static inline int
2989 __i915_gem_request_alloc(struct intel_engine_cs *engine,
2990                          struct i915_gem_context *ctx,
2991                          struct drm_i915_gem_request **req_out)
2992 {
2993         struct drm_i915_private *dev_priv = engine->i915;
2994         unsigned reset_counter = i915_reset_counter(&dev_priv->gpu_error);
2995         struct drm_i915_gem_request *req;
2996         int ret;
2997
2998         if (!req_out)
2999                 return -EINVAL;
3000
3001         *req_out = NULL;
3002
3003         /* ABI: Before userspace accesses the GPU (e.g. execbuffer), report
3004          * EIO if the GPU is already wedged, or EAGAIN to drop the struct_mutex
3005          * and restart.
3006          */
3007         ret = i915_gem_check_wedge(reset_counter, dev_priv->mm.interruptible);
3008         if (ret)
3009                 return ret;
3010
3011         req = kmem_cache_zalloc(dev_priv->requests, GFP_KERNEL);
3012         if (req == NULL)
3013                 return -ENOMEM;
3014
3015         ret = i915_gem_get_seqno(engine->i915, &req->seqno);
3016         if (ret)
3017                 goto err;
3018
3019         kref_init(&req->ref);
3020         req->i915 = dev_priv;
3021         req->engine = engine;
3022         req->ctx  = ctx;
3023         i915_gem_context_reference(req->ctx);
3024
3025         /*
3026          * Reserve space in the ring buffer for all the commands required to
3027          * eventually emit this request. This is to guarantee that the
3028          * i915_add_request() call can't fail. Note that the reserve may need
3029          * to be redone if the request is not actually submitted straight
3030          * away, e.g. because a GPU scheduler has deferred it.
3031          */
3032         req->reserved_space = MIN_SPACE_FOR_ADD_REQUEST;
3033
3034         if (i915.enable_execlists)
3035                 ret = intel_logical_ring_alloc_request_extras(req);
3036         else
3037                 ret = intel_ring_alloc_request_extras(req);
3038         if (ret)
3039                 goto err_ctx;
3040
3041         *req_out = req;
3042         return 0;
3043
3044 err_ctx:
3045         i915_gem_context_unreference(ctx);
3046 err:
3047         kmem_cache_free(dev_priv->requests, req);
3048         return ret;
3049 }
3050
3051 /**
3052  * i915_gem_request_alloc - allocate a request structure
3053  *
3054  * @engine: engine that we wish to issue the request on.
3055  * @ctx: context that the request will be associated with.
3056  *       This can be NULL if the request is not directly related to
3057  *       any specific user context, in which case this function will
3058  *       choose an appropriate context to use.
3059  *
3060  * Returns a pointer to the allocated request if successful,
3061  * or an error code if not.
3062  */
3063 struct drm_i915_gem_request *
3064 i915_gem_request_alloc(struct intel_engine_cs *engine,
3065                        struct i915_gem_context *ctx)
3066 {
3067         struct drm_i915_gem_request *req;
3068         int err;
3069
3070         if (ctx == NULL)
3071                 ctx = engine->i915->kernel_context;
3072         err = __i915_gem_request_alloc(engine, ctx, &req);
3073         return err ? ERR_PTR(err) : req;
3074 }
3075
3076 struct drm_i915_gem_request *
3077 i915_gem_find_active_request(struct intel_engine_cs *engine)
3078 {
3079         struct drm_i915_gem_request *request;
3080
3081         /* We are called by the error capture and reset at a random
3082          * point in time. In particular, note that neither is crucially
3083          * ordered with an interrupt. After a hang, the GPU is dead and we
3084          * assume that no more writes can happen (we waited long enough for
3085          * all writes that were in transaction to be flushed) - adding an
3086          * extra delay for a recent interrupt is pointless. Hence, we do
3087          * not need an engine->irq_seqno_barrier() before the seqno reads.
3088          */
3089         list_for_each_entry(request, &engine->request_list, list) {
3090                 if (i915_gem_request_completed(request))
3091                         continue;
3092
3093                 return request;
3094         }
3095
3096         return NULL;
3097 }
3098
3099 static void i915_gem_reset_engine_status(struct intel_engine_cs *engine)
3100 {
3101         struct drm_i915_gem_request *request;
3102         bool ring_hung;
3103
3104         request = i915_gem_find_active_request(engine);
3105         if (request == NULL)
3106                 return;
3107
3108         ring_hung = engine->hangcheck.score >= HANGCHECK_SCORE_RING_HUNG;
3109
3110         i915_set_reset_status(request->ctx, ring_hung);
3111         list_for_each_entry_continue(request, &engine->request_list, list)
3112                 i915_set_reset_status(request->ctx, false);
3113 }
3114
3115 static void i915_gem_reset_engine_cleanup(struct intel_engine_cs *engine)
3116 {
3117         struct intel_ringbuffer *buffer;
3118
3119         while (!list_empty(&engine->active_list)) {
3120                 struct drm_i915_gem_object *obj;
3121
3122                 obj = list_first_entry(&engine->active_list,
3123                                        struct drm_i915_gem_object,
3124                                        engine_list[engine->id]);
3125
3126                 i915_gem_object_retire__read(obj, engine->id);
3127         }
3128
3129         /*
3130          * Clear the execlists queue up before freeing the requests, as those
3131          * are the ones that keep the context and ringbuffer backing objects
3132          * pinned in place.
3133          */
3134
3135         if (i915.enable_execlists) {
3136                 /* Ensure irq handler finishes or is cancelled. */
3137                 tasklet_kill(&engine->irq_tasklet);
3138
3139                 intel_execlists_cancel_requests(engine);
3140         }
3141
3142         /*
3143          * We must free the requests after all the corresponding objects have
3144          * been moved off active lists. Which is the same order as the normal
3145          * retire_requests function does. This is important if object hold
3146          * implicit references on things like e.g. ppgtt address spaces through
3147          * the request.
3148          */
3149         while (!list_empty(&engine->request_list)) {
3150                 struct drm_i915_gem_request *request;
3151
3152                 request = list_first_entry(&engine->request_list,
3153                                            struct drm_i915_gem_request,
3154                                            list);
3155
3156                 i915_gem_request_retire(request);
3157         }
3158
3159         /* Having flushed all requests from all queues, we know that all
3160          * ringbuffers must now be empty. However, since we do not reclaim
3161          * all space when retiring the request (to prevent HEADs colliding
3162          * with rapid ringbuffer wraparound) the amount of available space
3163          * upon reset is less than when we start. Do one more pass over
3164          * all the ringbuffers to reset last_retired_head.
3165          */
3166         list_for_each_entry(buffer, &engine->buffers, link) {
3167                 buffer->last_retired_head = buffer->tail;
3168                 intel_ring_update_space(buffer);
3169         }
3170
3171         intel_ring_init_seqno(engine, engine->last_submitted_seqno);
3172
3173         engine->i915->gt.active_engines &= ~intel_engine_flag(engine);
3174 }
3175
3176 void i915_gem_reset(struct drm_device *dev)
3177 {
3178         struct drm_i915_private *dev_priv = to_i915(dev);
3179         struct intel_engine_cs *engine;
3180
3181         /*
3182          * Before we free the objects from the requests, we need to inspect
3183          * them for finding the guilty party. As the requests only borrow
3184          * their reference to the objects, the inspection must be done first.
3185          */
3186         for_each_engine(engine, dev_priv)
3187                 i915_gem_reset_engine_status(engine);
3188
3189         for_each_engine(engine, dev_priv)
3190                 i915_gem_reset_engine_cleanup(engine);
3191         mod_delayed_work(dev_priv->wq, &dev_priv->gt.idle_work, 0);
3192
3193         i915_gem_context_reset(dev);
3194
3195         i915_gem_restore_fences(dev);
3196
3197         WARN_ON(i915_verify_lists(dev));
3198 }
3199
3200 /**
3201  * This function clears the request list as sequence numbers are passed.
3202  * @engine: engine to retire requests on
3203  */
3204 void
3205 i915_gem_retire_requests_ring(struct intel_engine_cs *engine)
3206 {
3207         WARN_ON(i915_verify_lists(engine->dev));
3208
3209         /* Retire requests first as we use it above for the early return.
3210          * If we retire requests last, we may use a later seqno and so clear
3211          * the requests lists without clearing the active list, leading to
3212          * confusion.
3213          */
3214         while (!list_empty(&engine->request_list)) {
3215                 struct drm_i915_gem_request *request;
3216
3217                 request = list_first_entry(&engine->request_list,
3218                                            struct drm_i915_gem_request,
3219                                            list);
3220
3221                 if (!i915_gem_request_completed(request))
3222                         break;
3223
3224                 i915_gem_request_retire(request);
3225         }
3226
3227         /* Move any buffers on the active list that are no longer referenced
3228          * by the ringbuffer to the flushing/inactive lists as appropriate,
3229          * before we free the context associated with the requests.
3230          */
3231         while (!list_empty(&engine->active_list)) {
3232                 struct drm_i915_gem_object *obj;
3233
3234                 obj = list_first_entry(&engine->active_list,
3235                                        struct drm_i915_gem_object,
3236                                        engine_list[engine->id]);
3237
3238                 if (!list_empty(&obj->last_read_req[engine->id]->list))
3239                         break;
3240
3241                 i915_gem_object_retire__read(obj, engine->id);
3242         }
3243
3244         WARN_ON(i915_verify_lists(engine->dev));
3245 }
3246
3247 void i915_gem_retire_requests(struct drm_i915_private *dev_priv)
3248 {
3249         struct intel_engine_cs *engine;
3250
3251         lockdep_assert_held(&dev_priv->drm.struct_mutex);
3252
3253         if (dev_priv->gt.active_engines == 0)
3254                 return;
3255
3256         GEM_BUG_ON(!dev_priv->gt.awake);
3257
3258         for_each_engine(engine, dev_priv) {
3259                 i915_gem_retire_requests_ring(engine);
3260                 if (list_empty(&engine->request_list))
3261                         dev_priv->gt.active_engines &= ~intel_engine_flag(engine);
3262         }
3263
3264         if (dev_priv->gt.active_engines == 0)
3265                 queue_delayed_work(dev_priv->wq,
3266                                    &dev_priv->gt.idle_work,
3267                                    msecs_to_jiffies(100));
3268 }
3269
3270 static void
3271 i915_gem_retire_work_handler(struct work_struct *work)
3272 {
3273         struct drm_i915_private *dev_priv =
3274                 container_of(work, typeof(*dev_priv), gt.retire_work.work);
3275         struct drm_device *dev = &dev_priv->drm;
3276
3277         /* Come back later if the device is busy... */
3278         if (mutex_trylock(&dev->struct_mutex)) {
3279                 i915_gem_retire_requests(dev_priv);
3280                 mutex_unlock(&dev->struct_mutex);
3281         }
3282
3283         /* Keep the retire handler running until we are finally idle.
3284          * We do not need to do this test under locking as in the worst-case
3285          * we queue the retire worker once too often.
3286          */
3287         if (READ_ONCE(dev_priv->gt.awake))
3288                 queue_delayed_work(dev_priv->wq,
3289                                    &dev_priv->gt.retire_work,
3290                                    round_jiffies_up_relative(HZ));
3291 }
3292
3293 static void
3294 i915_gem_idle_work_handler(struct work_struct *work)
3295 {
3296         struct drm_i915_private *dev_priv =
3297                 container_of(work, typeof(*dev_priv), gt.idle_work.work);
3298         struct drm_device *dev = &dev_priv->drm;
3299         struct intel_engine_cs *engine;
3300         unsigned int stuck_engines;
3301         bool rearm_hangcheck;
3302
3303         if (!READ_ONCE(dev_priv->gt.awake))
3304                 return;
3305
3306         if (READ_ONCE(dev_priv->gt.active_engines))
3307                 return;
3308
3309         rearm_hangcheck =
3310                 cancel_delayed_work_sync(&dev_priv->gpu_error.hangcheck_work);
3311
3312         if (!mutex_trylock(&dev->struct_mutex)) {
3313                 /* Currently busy, come back later */
3314                 mod_delayed_work(dev_priv->wq,
3315                                  &dev_priv->gt.idle_work,
3316                                  msecs_to_jiffies(50));
3317                 goto out_rearm;
3318         }
3319
3320         if (dev_priv->gt.active_engines)
3321                 goto out_unlock;
3322
3323         for_each_engine(engine, dev_priv)
3324                 i915_gem_batch_pool_fini(&engine->batch_pool);
3325
3326         GEM_BUG_ON(!dev_priv->gt.awake);
3327         dev_priv->gt.awake = false;
3328         rearm_hangcheck = false;
3329
3330         stuck_engines = intel_kick_waiters(dev_priv);
3331         if (unlikely(stuck_engines)) {
3332                 DRM_DEBUG_DRIVER("kicked stuck waiters...missed irq\n");
3333                 dev_priv->gpu_error.missed_irq_rings |= stuck_engines;
3334         }
3335
3336         if (INTEL_GEN(dev_priv) >= 6)
3337                 gen6_rps_idle(dev_priv);
3338         intel_runtime_pm_put(dev_priv);
3339 out_unlock:
3340         mutex_unlock(&dev->struct_mutex);
3341
3342 out_rearm:
3343         if (rearm_hangcheck) {
3344                 GEM_BUG_ON(!dev_priv->gt.awake);
3345                 i915_queue_hangcheck(dev_priv);
3346         }
3347 }
3348
3349 /**
3350  * Ensures that an object will eventually get non-busy by flushing any required
3351  * write domains, emitting any outstanding lazy request and retiring and
3352  * completed requests.
3353  * @obj: object to flush
3354  */
3355 static int
3356 i915_gem_object_flush_active(struct drm_i915_gem_object *obj)
3357 {
3358         int i;
3359
3360         if (!obj->active)
3361                 return 0;
3362
3363         for (i = 0; i < I915_NUM_ENGINES; i++) {
3364                 struct drm_i915_gem_request *req;
3365
3366                 req = obj->last_read_req[i];
3367                 if (req == NULL)
3368                         continue;
3369
3370                 if (i915_gem_request_completed(req))
3371                         i915_gem_object_retire__read(obj, i);
3372         }
3373
3374         return 0;
3375 }
3376
3377 /**
3378  * i915_gem_wait_ioctl - implements DRM_IOCTL_I915_GEM_WAIT
3379  * @dev: drm device pointer
3380  * @data: ioctl data blob
3381  * @file: drm file pointer
3382  *
3383  * Returns 0 if successful, else an error is returned with the remaining time in
3384  * the timeout parameter.
3385  *  -ETIME: object is still busy after timeout
3386  *  -ERESTARTSYS: signal interrupted the wait
3387  *  -ENONENT: object doesn't exist
3388  * Also possible, but rare:
3389  *  -EAGAIN: GPU wedged
3390  *  -ENOMEM: damn
3391  *  -ENODEV: Internal IRQ fail
3392  *  -E?: The add request failed
3393  *
3394  * The wait ioctl with a timeout of 0 reimplements the busy ioctl. With any
3395  * non-zero timeout parameter the wait ioctl will wait for the given number of
3396  * nanoseconds on an object becoming unbusy. Since the wait itself does so
3397  * without holding struct_mutex the object may become re-busied before this
3398  * function completes. A similar but shorter * race condition exists in the busy
3399  * ioctl
3400  */
3401 int
3402 i915_gem_wait_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
3403 {
3404         struct drm_i915_gem_wait *args = data;
3405         struct drm_i915_gem_object *obj;
3406         struct drm_i915_gem_request *req[I915_NUM_ENGINES];
3407         int i, n = 0;
3408         int ret;
3409
3410         if (args->flags != 0)
3411                 return -EINVAL;
3412
3413         ret = i915_mutex_lock_interruptible(dev);
3414         if (ret)
3415                 return ret;
3416
3417         obj = to_intel_bo(drm_gem_object_lookup(file, args->bo_handle));
3418         if (&obj->base == NULL) {
3419                 mutex_unlock(&dev->struct_mutex);
3420                 return -ENOENT;
3421         }
3422
3423         /* Need to make sure the object gets inactive eventually. */
3424         ret = i915_gem_object_flush_active(obj);
3425         if (ret)
3426                 goto out;
3427
3428         if (!obj->active)
3429                 goto out;
3430
3431         /* Do this after OLR check to make sure we make forward progress polling
3432          * on this IOCTL with a timeout == 0 (like busy ioctl)
3433          */
3434         if (args->timeout_ns == 0) {
3435                 ret = -ETIME;
3436                 goto out;
3437         }
3438
3439         drm_gem_object_unreference(&obj->base);
3440
3441         for (i = 0; i < I915_NUM_ENGINES; i++) {
3442                 if (obj->last_read_req[i] == NULL)
3443                         continue;
3444
3445                 req[n++] = i915_gem_request_reference(obj->last_read_req[i]);
3446         }
3447
3448         mutex_unlock(&dev->struct_mutex);
3449
3450         for (i = 0; i < n; i++) {
3451                 if (ret == 0)
3452                         ret = __i915_wait_request(req[i], true,
3453                                                   args->timeout_ns > 0 ? &args->timeout_ns : NULL,
3454                                                   to_rps_client(file));
3455                 i915_gem_request_unreference(req[i]);
3456         }
3457         return ret;
3458
3459 out:
3460         drm_gem_object_unreference(&obj->base);
3461         mutex_unlock(&dev->struct_mutex);
3462         return ret;
3463 }
3464
3465 static int
3466 __i915_gem_object_sync(struct drm_i915_gem_object *obj,
3467                        struct intel_engine_cs *to,
3468                        struct drm_i915_gem_request *from_req,
3469                        struct drm_i915_gem_request **to_req)
3470 {
3471         struct intel_engine_cs *from;
3472         int ret;
3473
3474         from = i915_gem_request_get_engine(from_req);
3475         if (to == from)
3476                 return 0;
3477
3478         if (i915_gem_request_completed(from_req))
3479                 return 0;
3480
3481         if (!i915_semaphore_is_enabled(to_i915(obj->base.dev))) {
3482                 struct drm_i915_private *i915 = to_i915(obj->base.dev);
3483                 ret = __i915_wait_request(from_req,
3484                                           i915->mm.interruptible,
3485                                           NULL,
3486                                           &i915->rps.semaphores);
3487                 if (ret)
3488                         return ret;
3489
3490                 i915_gem_object_retire_request(obj, from_req);
3491         } else {
3492                 int idx = intel_ring_sync_index(from, to);
3493                 u32 seqno = i915_gem_request_get_seqno(from_req);
3494
3495                 WARN_ON(!to_req);
3496
3497                 if (seqno <= from->semaphore.sync_seqno[idx])
3498                         return 0;
3499
3500                 if (*to_req == NULL) {
3501                         struct drm_i915_gem_request *req;
3502
3503                         req = i915_gem_request_alloc(to, NULL);
3504                         if (IS_ERR(req))
3505                                 return PTR_ERR(req);
3506
3507                         *to_req = req;
3508                 }
3509
3510                 trace_i915_gem_ring_sync_to(*to_req, from, from_req);
3511                 ret = to->semaphore.sync_to(*to_req, from, seqno);
3512                 if (ret)
3513                         return ret;
3514
3515                 /* We use last_read_req because sync_to()
3516                  * might have just caused seqno wrap under
3517                  * the radar.
3518                  */
3519                 from->semaphore.sync_seqno[idx] =
3520                         i915_gem_request_get_seqno(obj->last_read_req[from->id]);
3521         }
3522
3523         return 0;
3524 }
3525
3526 /**
3527  * i915_gem_object_sync - sync an object to a ring.
3528  *
3529  * @obj: object which may be in use on another ring.
3530  * @to: ring we wish to use the object on. May be NULL.
3531  * @to_req: request we wish to use the object for. See below.
3532  *          This will be allocated and returned if a request is
3533  *          required but not passed in.
3534  *
3535  * This code is meant to abstract object synchronization with the GPU.
3536  * Calling with NULL implies synchronizing the object with the CPU
3537  * rather than a particular GPU ring. Conceptually we serialise writes
3538  * between engines inside the GPU. We only allow one engine to write
3539  * into a buffer at any time, but multiple readers. To ensure each has
3540  * a coherent view of memory, we must:
3541  *
3542  * - If there is an outstanding write request to the object, the new
3543  *   request must wait for it to complete (either CPU or in hw, requests
3544  *   on the same ring will be naturally ordered).
3545  *
3546  * - If we are a write request (pending_write_domain is set), the new
3547  *   request must wait for outstanding read requests to complete.
3548  *
3549  * For CPU synchronisation (NULL to) no request is required. For syncing with
3550  * rings to_req must be non-NULL. However, a request does not have to be
3551  * pre-allocated. If *to_req is NULL and sync commands will be emitted then a
3552  * request will be allocated automatically and returned through *to_req. Note
3553  * that it is not guaranteed that commands will be emitted (because the system
3554  * might already be idle). Hence there is no need to create a request that
3555  * might never have any work submitted. Note further that if a request is
3556  * returned in *to_req, it is the responsibility of the caller to submit
3557  * that request (after potentially adding more work to it).
3558  *
3559  * Returns 0 if successful, else propagates up the lower layer error.
3560  */
3561 int
3562 i915_gem_object_sync(struct drm_i915_gem_object *obj,
3563                      struct intel_engine_cs *to,
3564                      struct drm_i915_gem_request **to_req)
3565 {
3566         const bool readonly = obj->base.pending_write_domain == 0;
3567         struct drm_i915_gem_request *req[I915_NUM_ENGINES];
3568         int ret, i, n;
3569
3570         if (!obj->active)
3571                 return 0;
3572
3573         if (to == NULL)
3574                 return i915_gem_object_wait_rendering(obj, readonly);
3575
3576         n = 0;
3577         if (readonly) {
3578                 if (obj->last_write_req)
3579                         req[n++] = obj->last_write_req;
3580         } else {
3581                 for (i = 0; i < I915_NUM_ENGINES; i++)
3582                         if (obj->last_read_req[i])
3583                                 req[n++] = obj->last_read_req[i];
3584         }
3585         for (i = 0; i < n; i++) {
3586                 ret = __i915_gem_object_sync(obj, to, req[i], to_req);
3587                 if (ret)
3588                         return ret;
3589         }
3590
3591         return 0;
3592 }
3593
3594 static void i915_gem_object_finish_gtt(struct drm_i915_gem_object *obj)
3595 {
3596         u32 old_write_domain, old_read_domains;
3597
3598         /* Force a pagefault for domain tracking on next user access */
3599         i915_gem_release_mmap(obj);
3600
3601         if ((obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0)
3602                 return;
3603
3604         old_read_domains = obj->base.read_domains;
3605         old_write_domain = obj->base.write_domain;
3606
3607         obj->base.read_domains &= ~I915_GEM_DOMAIN_GTT;
3608         obj->base.write_domain &= ~I915_GEM_DOMAIN_GTT;
3609
3610         trace_i915_gem_object_change_domain(obj,
3611                                             old_read_domains,
3612                                             old_write_domain);
3613 }
3614
3615 static void __i915_vma_iounmap(struct i915_vma *vma)
3616 {
3617         GEM_BUG_ON(vma->pin_count);
3618
3619         if (vma->iomap == NULL)
3620                 return;
3621
3622         io_mapping_unmap(vma->iomap);
3623         vma->iomap = NULL;
3624 }
3625
3626 static int __i915_vma_unbind(struct i915_vma *vma, bool wait)
3627 {
3628         struct drm_i915_gem_object *obj = vma->obj;
3629         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
3630         int ret;
3631
3632         if (list_empty(&vma->obj_link))
3633                 return 0;
3634
3635         if (!drm_mm_node_allocated(&vma->node)) {
3636                 i915_gem_vma_destroy(vma);
3637                 return 0;
3638         }
3639
3640         if (vma->pin_count)
3641                 return -EBUSY;
3642
3643         BUG_ON(obj->pages == NULL);
3644
3645         if (wait) {
3646                 ret = i915_gem_object_wait_rendering(obj, false);
3647                 if (ret)
3648                         return ret;
3649         }
3650
3651         if (vma->is_ggtt && vma->ggtt_view.type == I915_GGTT_VIEW_NORMAL) {
3652                 i915_gem_object_finish_gtt(obj);
3653
3654                 /* release the fence reg _after_ flushing */
3655                 ret = i915_gem_object_put_fence(obj);
3656                 if (ret)
3657                         return ret;
3658
3659                 __i915_vma_iounmap(vma);
3660         }
3661
3662         trace_i915_vma_unbind(vma);
3663
3664         vma->vm->unbind_vma(vma);
3665         vma->bound = 0;
3666
3667         list_del_init(&vma->vm_link);
3668         if (vma->is_ggtt) {
3669                 if (vma->ggtt_view.type == I915_GGTT_VIEW_NORMAL) {
3670                         obj->map_and_fenceable = false;
3671                 } else if (vma->ggtt_view.pages) {
3672                         sg_free_table(vma->ggtt_view.pages);
3673                         kfree(vma->ggtt_view.pages);
3674                 }
3675                 vma->ggtt_view.pages = NULL;
3676         }
3677
3678         drm_mm_remove_node(&vma->node);
3679         i915_gem_vma_destroy(vma);
3680
3681         /* Since the unbound list is global, only move to that list if
3682          * no more VMAs exist. */
3683         if (list_empty(&obj->vma_list))
3684                 list_move_tail(&obj->global_list, &dev_priv->mm.unbound_list);
3685
3686         /* And finally now the object is completely decoupled from this vma,
3687          * we can drop its hold on the backing storage and allow it to be
3688          * reaped by the shrinker.
3689          */
3690         i915_gem_object_unpin_pages(obj);
3691
3692         return 0;
3693 }
3694
3695 int i915_vma_unbind(struct i915_vma *vma)
3696 {
3697         return __i915_vma_unbind(vma, true);
3698 }
3699
3700 int __i915_vma_unbind_no_wait(struct i915_vma *vma)
3701 {
3702         return __i915_vma_unbind(vma, false);
3703 }
3704
3705 int i915_gem_wait_for_idle(struct drm_i915_private *dev_priv)
3706 {
3707         struct intel_engine_cs *engine;
3708         int ret;
3709
3710         lockdep_assert_held(&dev_priv->drm.struct_mutex);
3711
3712         for_each_engine(engine, dev_priv) {
3713                 if (engine->last_context == NULL)
3714                         continue;
3715
3716                 ret = intel_engine_idle(engine);
3717                 if (ret)
3718                         return ret;
3719         }
3720
3721         WARN_ON(i915_verify_lists(dev));
3722         return 0;
3723 }
3724
3725 static bool i915_gem_valid_gtt_space(struct i915_vma *vma,
3726                                      unsigned long cache_level)
3727 {
3728         struct drm_mm_node *gtt_space = &vma->node;
3729         struct drm_mm_node *other;
3730
3731         /*
3732          * On some machines we have to be careful when putting differing types
3733          * of snoopable memory together to avoid the prefetcher crossing memory
3734          * domains and dying. During vm initialisation, we decide whether or not
3735          * these constraints apply and set the drm_mm.color_adjust
3736          * appropriately.
3737          */
3738         if (vma->vm->mm.color_adjust == NULL)
3739                 return true;
3740
3741         if (!drm_mm_node_allocated(gtt_space))
3742                 return true;
3743
3744         if (list_empty(&gtt_space->node_list))
3745                 return true;
3746
3747         other = list_entry(gtt_space->node_list.prev, struct drm_mm_node, node_list);
3748         if (other->allocated && !other->hole_follows && other->color != cache_level)
3749                 return false;
3750
3751         other = list_entry(gtt_space->node_list.next, struct drm_mm_node, node_list);
3752         if (other->allocated && !gtt_space->hole_follows && other->color != cache_level)
3753                 return false;
3754
3755         return true;
3756 }
3757
3758 /**
3759  * Finds free space in the GTT aperture and binds the object or a view of it
3760  * there.
3761  * @obj: object to bind
3762  * @vm: address space to bind into
3763  * @ggtt_view: global gtt view if applicable
3764  * @alignment: requested alignment
3765  * @flags: mask of PIN_* flags to use
3766  */
3767 static struct i915_vma *
3768 i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
3769                            struct i915_address_space *vm,
3770                            const struct i915_ggtt_view *ggtt_view,
3771                            unsigned alignment,
3772                            uint64_t flags)
3773 {
3774         struct drm_device *dev = obj->base.dev;
3775         struct drm_i915_private *dev_priv = to_i915(dev);
3776         struct i915_ggtt *ggtt = &dev_priv->ggtt;
3777         u32 fence_alignment, unfenced_alignment;
3778         u32 search_flag, alloc_flag;
3779         u64 start, end;
3780         u64 size, fence_size;
3781         struct i915_vma *vma;
3782         int ret;
3783
3784         if (i915_is_ggtt(vm)) {
3785                 u32 view_size;
3786
3787                 if (WARN_ON(!ggtt_view))
3788                         return ERR_PTR(-EINVAL);
3789
3790                 view_size = i915_ggtt_view_size(obj, ggtt_view);
3791
3792                 fence_size = i915_gem_get_gtt_size(dev,
3793                                                    view_size,
3794                                                    obj->tiling_mode);
3795                 fence_alignment = i915_gem_get_gtt_alignment(dev,
3796                                                              view_size,
3797                                                              obj->tiling_mode,
3798                                                              true);
3799                 unfenced_alignment = i915_gem_get_gtt_alignment(dev,
3800                                                                 view_size,
3801                                                                 obj->tiling_mode,
3802                                                                 false);
3803                 size = flags & PIN_MAPPABLE ? fence_size : view_size;
3804         } else {
3805                 fence_size = i915_gem_get_gtt_size(dev,
3806                                                    obj->base.size,
3807                                                    obj->tiling_mode);
3808                 fence_alignment = i915_gem_get_gtt_alignment(dev,
3809                                                              obj->base.size,
3810                                                              obj->tiling_mode,
3811                                                              true);
3812                 unfenced_alignment =
3813                         i915_gem_get_gtt_alignment(dev,
3814                                                    obj->base.size,
3815                                                    obj->tiling_mode,
3816                                                    false);
3817                 size = flags & PIN_MAPPABLE ? fence_size : obj->base.size;
3818         }
3819
3820         start = flags & PIN_OFFSET_BIAS ? flags & PIN_OFFSET_MASK : 0;
3821         end = vm->total;
3822         if (flags & PIN_MAPPABLE)
3823                 end = min_t(u64, end, ggtt->mappable_end);
3824         if (flags & PIN_ZONE_4G)
3825                 end = min_t(u64, end, (1ULL << 32) - PAGE_SIZE);
3826
3827         if (alignment == 0)
3828                 alignment = flags & PIN_MAPPABLE ? fence_alignment :
3829                                                 unfenced_alignment;
3830         if (flags & PIN_MAPPABLE && alignment & (fence_alignment - 1)) {
3831                 DRM_DEBUG("Invalid object (view type=%u) alignment requested %u\n",
3832                           ggtt_view ? ggtt_view->type : 0,
3833                           alignment);
3834                 return ERR_PTR(-EINVAL);
3835         }
3836
3837         /* If binding the object/GGTT view requires more space than the entire
3838          * aperture has, reject it early before evicting everything in a vain
3839          * attempt to find space.
3840          */
3841         if (size > end) {
3842                 DRM_DEBUG("Attempting to bind an object (view type=%u) larger than the aperture: size=%llu > %s aperture=%llu\n",
3843                           ggtt_view ? ggtt_view->type : 0,
3844                           size,
3845                           flags & PIN_MAPPABLE ? "mappable" : "total",
3846                           end);
3847                 return ERR_PTR(-E2BIG);
3848         }
3849
3850         ret = i915_gem_object_get_pages(obj);
3851         if (ret)
3852                 return ERR_PTR(ret);
3853
3854         i915_gem_object_pin_pages(obj);
3855
3856         vma = ggtt_view ? i915_gem_obj_lookup_or_create_ggtt_vma(obj, ggtt_view) :
3857                           i915_gem_obj_lookup_or_create_vma(obj, vm);
3858
3859         if (IS_ERR(vma))
3860                 goto err_unpin;
3861
3862         if (flags & PIN_OFFSET_FIXED) {
3863                 uint64_t offset = flags & PIN_OFFSET_MASK;
3864
3865                 if (offset & (alignment - 1) || offset + size > end) {
3866                         ret = -EINVAL;
3867                         goto err_free_vma;
3868                 }
3869                 vma->node.start = offset;
3870                 vma->node.size = size;
3871                 vma->node.color = obj->cache_level;
3872                 ret = drm_mm_reserve_node(&vm->mm, &vma->node);
3873                 if (ret) {
3874                         ret = i915_gem_evict_for_vma(vma);
3875                         if (ret == 0)
3876                                 ret = drm_mm_reserve_node(&vm->mm, &vma->node);
3877                 }
3878                 if (ret)
3879                         goto err_free_vma;
3880         } else {
3881                 if (flags & PIN_HIGH) {
3882                         search_flag = DRM_MM_SEARCH_BELOW;
3883                         alloc_flag = DRM_MM_CREATE_TOP;
3884                 } else {
3885                         search_flag = DRM_MM_SEARCH_DEFAULT;
3886                         alloc_flag = DRM_MM_CREATE_DEFAULT;
3887                 }
3888
3889 search_free:
3890                 ret = drm_mm_insert_node_in_range_generic(&vm->mm, &vma->node,
3891                                                           size, alignment,
3892                                                           obj->cache_level,
3893                                                           start, end,
3894                                                           search_flag,
3895                                                           alloc_flag);
3896                 if (ret) {
3897                         ret = i915_gem_evict_something(dev, vm, size, alignment,
3898                                                        obj->cache_level,
3899                                                        start, end,
3900                                                        flags);
3901                         if (ret == 0)
3902                                 goto search_free;
3903
3904                         goto err_free_vma;
3905                 }
3906         }
3907         if (WARN_ON(!i915_gem_valid_gtt_space(vma, obj->cache_level))) {
3908                 ret = -EINVAL;
3909                 goto err_remove_node;
3910         }
3911
3912         trace_i915_vma_bind(vma, flags);
3913         ret = i915_vma_bind(vma, obj->cache_level, flags);
3914         if (ret)
3915                 goto err_remove_node;
3916
3917         list_move_tail(&obj->global_list, &dev_priv->mm.bound_list);
3918         list_add_tail(&vma->vm_link, &vm->inactive_list);
3919
3920         return vma;
3921
3922 err_remove_node:
3923         drm_mm_remove_node(&vma->node);
3924 err_free_vma:
3925         i915_gem_vma_destroy(vma);
3926         vma = ERR_PTR(ret);
3927 err_unpin:
3928         i915_gem_object_unpin_pages(obj);
3929         return vma;
3930 }
3931
3932 bool
3933 i915_gem_clflush_object(struct drm_i915_gem_object *obj,
3934                         bool force)
3935 {
3936         /* If we don't have a page list set up, then we're not pinned
3937          * to GPU, and we can ignore the cache flush because it'll happen
3938          * again at bind time.
3939          */
3940         if (obj->pages == NULL)
3941                 return false;
3942
3943         /*
3944          * Stolen memory is always coherent with the GPU as it is explicitly
3945          * marked as wc by the system, or the system is cache-coherent.
3946          */
3947         if (obj->stolen || obj->phys_handle)
3948                 return false;
3949
3950         /* If the GPU is snooping the contents of the CPU cache,
3951          * we do not need to manually clear the CPU cache lines.  However,
3952          * the caches are only snooped when the render cache is
3953          * flushed/invalidated.  As we always have to emit invalidations
3954          * and flushes when moving into and out of the RENDER domain, correct
3955          * snooping behaviour occurs naturally as the result of our domain
3956          * tracking.
3957          */
3958         if (!force && cpu_cache_is_coherent(obj->base.dev, obj->cache_level)) {
3959                 obj->cache_dirty = true;
3960                 return false;
3961         }
3962
3963         trace_i915_gem_object_clflush(obj);
3964         drm_clflush_sg(obj->pages);
3965         obj->cache_dirty = false;
3966
3967         return true;
3968 }
3969
3970 /** Flushes the GTT write domain for the object if it's dirty. */
3971 static void
3972 i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj)
3973 {
3974         uint32_t old_write_domain;
3975
3976         if (obj->base.write_domain != I915_GEM_DOMAIN_GTT)
3977                 return;
3978
3979         /* No actual flushing is required for the GTT write domain.  Writes
3980          * to it immediately go to main memory as far as we know, so there's
3981          * no chipset flush.  It also doesn't land in render cache.
3982          *
3983          * However, we do have to enforce the order so that all writes through
3984          * the GTT land before any writes to the device, such as updates to
3985          * the GATT itself.
3986          */
3987         wmb();
3988
3989         old_write_domain = obj->base.write_domain;
3990         obj->base.write_domain = 0;
3991
3992         intel_fb_obj_flush(obj, false, ORIGIN_GTT);
3993
3994         trace_i915_gem_object_change_domain(obj,
3995                                             obj->base.read_domains,
3996                                             old_write_domain);
3997 }
3998
3999 /** Flushes the CPU write domain for the object if it's dirty. */
4000 static void
4001 i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj)
4002 {
4003         uint32_t old_write_domain;
4004
4005         if (obj->base.write_domain != I915_GEM_DOMAIN_CPU)
4006                 return;
4007
4008         if (i915_gem_clflush_object(obj, obj->pin_display))
4009                 i915_gem_chipset_flush(to_i915(obj->base.dev));
4010
4011         old_write_domain = obj->base.write_domain;
4012         obj->base.write_domain = 0;
4013
4014         intel_fb_obj_flush(obj, false, ORIGIN_CPU);
4015
4016         trace_i915_gem_object_change_domain(obj,
4017                                             obj->base.read_domains,
4018                                             old_write_domain);
4019 }
4020
4021 /**
4022  * Moves a single object to the GTT read, and possibly write domain.
4023  * @obj: object to act on
4024  * @write: ask for write access or read only
4025  *
4026  * This function returns when the move is complete, including waiting on
4027  * flushes to occur.
4028  */
4029 int
4030 i915_gem_object_set_to_gtt_domain(struct drm_i915_gem_object *obj, bool write)
4031 {
4032         struct drm_device *dev = obj->base.dev;
4033         struct drm_i915_private *dev_priv = to_i915(dev);
4034         struct i915_ggtt *ggtt = &dev_priv->ggtt;
4035         uint32_t old_write_domain, old_read_domains;
4036         struct i915_vma *vma;
4037         int ret;
4038
4039         if (obj->base.write_domain == I915_GEM_DOMAIN_GTT)
4040                 return 0;
4041
4042         ret = i915_gem_object_wait_rendering(obj, !write);
4043         if (ret)
4044                 return ret;
4045
4046         /* Flush and acquire obj->pages so that we are coherent through
4047          * direct access in memory with previous cached writes through
4048          * shmemfs and that our cache domain tracking remains valid.
4049          * For example, if the obj->filp was moved to swap without us
4050          * being notified and releasing the pages, we would mistakenly
4051          * continue to assume that the obj remained out of the CPU cached
4052          * domain.
4053          */
4054         ret = i915_gem_object_get_pages(obj);
4055         if (ret)
4056                 return ret;
4057
4058         i915_gem_object_flush_cpu_write_domain(obj);
4059
4060         /* Serialise direct access to this object with the barriers for
4061          * coherent writes from the GPU, by effectively invalidating the
4062          * GTT domain upon first access.
4063          */
4064         if ((obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0)
4065                 mb();
4066
4067         old_write_domain = obj->base.write_domain;
4068         old_read_domains = obj->base.read_domains;
4069
4070         /* It should now be out of any other write domains, and we can update
4071          * the domain values for our changes.
4072          */
4073         BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_GTT) != 0);
4074         obj->base.read_domains |= I915_GEM_DOMAIN_GTT;
4075         if (write) {
4076                 obj->base.read_domains = I915_GEM_DOMAIN_GTT;
4077                 obj->base.write_domain = I915_GEM_DOMAIN_GTT;
4078                 obj->dirty = 1;
4079         }
4080
4081         trace_i915_gem_object_change_domain(obj,
4082                                             old_read_domains,
4083                                             old_write_domain);
4084
4085         /* And bump the LRU for this access */
4086         vma = i915_gem_obj_to_ggtt(obj);
4087         if (vma && drm_mm_node_allocated(&vma->node) && !obj->active)
4088                 list_move_tail(&vma->vm_link,
4089                                &ggtt->base.inactive_list);
4090
4091         return 0;
4092 }
4093
4094 /**
4095  * Changes the cache-level of an object across all VMA.
4096  * @obj: object to act on
4097  * @cache_level: new cache level to set for the object
4098  *
4099  * After this function returns, the object will be in the new cache-level
4100  * across all GTT and the contents of the backing storage will be coherent,
4101  * with respect to the new cache-level. In order to keep the backing storage
4102  * coherent for all users, we only allow a single cache level to be set
4103  * globally on the object and prevent it from being changed whilst the
4104  * hardware is reading from the object. That is if the object is currently
4105  * on the scanout it will be set to uncached (or equivalent display
4106  * cache coherency) and all non-MOCS GPU access will also be uncached so
4107  * that all direct access to the scanout remains coherent.
4108  */
4109 int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
4110                                     enum i915_cache_level cache_level)
4111 {
4112         struct drm_device *dev = obj->base.dev;
4113         struct i915_vma *vma, *next;
4114         bool bound = false;
4115         int ret = 0;
4116
4117         if (obj->cache_level == cache_level)
4118                 goto out;
4119
4120         /* Inspect the list of currently bound VMA and unbind any that would
4121          * be invalid given the new cache-level. This is principally to
4122          * catch the issue of the CS prefetch crossing page boundaries and
4123          * reading an invalid PTE on older architectures.
4124          */
4125         list_for_each_entry_safe(vma, next, &obj->vma_list, obj_link) {
4126                 if (!drm_mm_node_allocated(&vma->node))
4127                         continue;
4128
4129                 if (vma->pin_count) {
4130                         DRM_DEBUG("can not change the cache level of pinned objects\n");
4131                         return -EBUSY;
4132                 }
4133
4134                 if (!i915_gem_valid_gtt_space(vma, cache_level)) {
4135                         ret = i915_vma_unbind(vma);
4136                         if (ret)
4137                                 return ret;
4138                 } else
4139                         bound = true;
4140         }
4141
4142         /* We can reuse the existing drm_mm nodes but need to change the
4143          * cache-level on the PTE. We could simply unbind them all and
4144          * rebind with the correct cache-level on next use. However since
4145          * we already have a valid slot, dma mapping, pages etc, we may as
4146          * rewrite the PTE in the belief that doing so tramples upon less
4147          * state and so involves less work.
4148          */
4149         if (bound) {
4150                 /* Before we change the PTE, the GPU must not be accessing it.
4151                  * If we wait upon the object, we know that all the bound
4152                  * VMA are no longer active.
4153                  */
4154                 ret = i915_gem_object_wait_rendering(obj, false);
4155                 if (ret)
4156                         return ret;
4157
4158                 if (!HAS_LLC(dev) && cache_level != I915_CACHE_NONE) {
4159                         /* Access to snoopable pages through the GTT is
4160                          * incoherent and on some machines causes a hard
4161                          * lockup. Relinquish the CPU mmaping to force
4162                          * userspace to refault in the pages and we can
4163                          * then double check if the GTT mapping is still
4164                          * valid for that pointer access.
4165                          */
4166                         i915_gem_release_mmap(obj);
4167
4168                         /* As we no longer need a fence for GTT access,
4169                          * we can relinquish it now (and so prevent having
4170                          * to steal a fence from someone else on the next
4171                          * fence request). Note GPU activity would have
4172                          * dropped the fence as all snoopable access is
4173                          * supposed to be linear.
4174                          */
4175                         ret = i915_gem_object_put_fence(obj);
4176                         if (ret)
4177                                 return ret;
4178                 } else {
4179                         /* We either have incoherent backing store and
4180                          * so no GTT access or the architecture is fully
4181                          * coherent. In such cases, existing GTT mmaps
4182                          * ignore the cache bit in the PTE and we can
4183                          * rewrite it without confusing the GPU or having
4184                          * to force userspace to fault back in its mmaps.
4185                          */
4186                 }
4187
4188                 list_for_each_entry(vma, &obj->vma_list, obj_link) {
4189                         if (!drm_mm_node_allocated(&vma->node))
4190                                 continue;
4191
4192                         ret = i915_vma_bind(vma, cache_level, PIN_UPDATE);
4193                         if (ret)
4194                                 return ret;
4195                 }
4196         }
4197
4198         list_for_each_entry(vma, &obj->vma_list, obj_link)
4199                 vma->node.color = cache_level;
4200         obj->cache_level = cache_level;
4201
4202 out:
4203         /* Flush the dirty CPU caches to the backing storage so that the
4204          * object is now coherent at its new cache level (with respect
4205          * to the access domain).
4206          */
4207         if (obj->cache_dirty && cpu_write_needs_clflush(obj)) {
4208                 if (i915_gem_clflush_object(obj, true))
4209                         i915_gem_chipset_flush(to_i915(obj->base.dev));
4210         }
4211
4212         return 0;
4213 }
4214
4215 int i915_gem_get_caching_ioctl(struct drm_device *dev, void *data,
4216                                struct drm_file *file)
4217 {
4218         struct drm_i915_gem_caching *args = data;
4219         struct drm_i915_gem_object *obj;
4220
4221         obj = to_intel_bo(drm_gem_object_lookup(file, args->handle));
4222         if (&obj->base == NULL)
4223                 return -ENOENT;
4224
4225         switch (obj->cache_level) {
4226         case I915_CACHE_LLC:
4227         case I915_CACHE_L3_LLC:
4228                 args->caching = I915_CACHING_CACHED;
4229                 break;
4230
4231         case I915_CACHE_WT:
4232                 args->caching = I915_CACHING_DISPLAY;
4233                 break;
4234
4235         default:
4236                 args->caching = I915_CACHING_NONE;
4237                 break;
4238         }
4239
4240         drm_gem_object_unreference_unlocked(&obj->base);
4241         return 0;
4242 }
4243
4244 int i915_gem_set_caching_ioctl(struct drm_device *dev, void *data,
4245                                struct drm_file *file)
4246 {
4247         struct drm_i915_private *dev_priv = to_i915(dev);
4248         struct drm_i915_gem_caching *args = data;
4249         struct drm_i915_gem_object *obj;
4250         enum i915_cache_level level;
4251         int ret;
4252
4253         switch (args->caching) {
4254         case I915_CACHING_NONE:
4255                 level = I915_CACHE_NONE;
4256                 break;
4257         case I915_CACHING_CACHED:
4258                 /*
4259                  * Due to a HW issue on BXT A stepping, GPU stores via a
4260                  * snooped mapping may leave stale data in a corresponding CPU
4261                  * cacheline, whereas normally such cachelines would get
4262                  * invalidated.
4263                  */
4264                 if (!HAS_LLC(dev) && !HAS_SNOOP(dev))
4265                         return -ENODEV;
4266
4267                 level = I915_CACHE_LLC;
4268                 break;
4269         case I915_CACHING_DISPLAY:
4270                 level = HAS_WT(dev) ? I915_CACHE_WT : I915_CACHE_NONE;
4271                 break;
4272         default:
4273                 return -EINVAL;
4274         }
4275
4276         intel_runtime_pm_get(dev_priv);
4277
4278         ret = i915_mutex_lock_interruptible(dev);
4279         if (ret)
4280                 goto rpm_put;
4281
4282         obj = to_intel_bo(drm_gem_object_lookup(file, args->handle));
4283         if (&obj->base == NULL) {
4284                 ret = -ENOENT;
4285                 goto unlock;
4286         }
4287
4288         ret = i915_gem_object_set_cache_level(obj, level);
4289
4290         drm_gem_object_unreference(&obj->base);
4291 unlock:
4292         mutex_unlock(&dev->struct_mutex);
4293 rpm_put:
4294         intel_runtime_pm_put(dev_priv);
4295
4296         return ret;
4297 }
4298
4299 /*
4300  * Prepare buffer for display plane (scanout, cursors, etc).
4301  * Can be called from an uninterruptible phase (modesetting) and allows
4302  * any flushes to be pipelined (for pageflips).
4303  */
4304 int
4305 i915_gem_object_pin_to_display_plane(struct drm_i915_gem_object *obj,
4306                                      u32 alignment,
4307                                      const struct i915_ggtt_view *view)
4308 {
4309         u32 old_read_domains, old_write_domain;
4310         int ret;
4311
4312         /* Mark the pin_display early so that we account for the
4313          * display coherency whilst setting up the cache domains.
4314          */
4315         obj->pin_display++;
4316
4317         /* The display engine is not coherent with the LLC cache on gen6.  As
4318          * a result, we make sure that the pinning that is about to occur is
4319          * done with uncached PTEs. This is lowest common denominator for all
4320          * chipsets.
4321          *
4322          * However for gen6+, we could do better by using the GFDT bit instead
4323          * of uncaching, which would allow us to flush all the LLC-cached data
4324          * with that bit in the PTE to main memory with just one PIPE_CONTROL.
4325          */
4326         ret = i915_gem_object_set_cache_level(obj,
4327                                               HAS_WT(obj->base.dev) ? I915_CACHE_WT : I915_CACHE_NONE);
4328         if (ret)
4329                 goto err_unpin_display;
4330
4331         /* As the user may map the buffer once pinned in the display plane
4332          * (e.g. libkms for the bootup splash), we have to ensure that we
4333          * always use map_and_fenceable for all scanout buffers.
4334          */
4335         ret = i915_gem_object_ggtt_pin(obj, view, alignment,
4336                                        view->type == I915_GGTT_VIEW_NORMAL ?
4337                                        PIN_MAPPABLE : 0);
4338         if (ret)
4339                 goto err_unpin_display;
4340
4341         i915_gem_object_flush_cpu_write_domain(obj);
4342
4343         old_write_domain = obj->base.write_domain;
4344         old_read_domains = obj->base.read_domains;
4345
4346         /* It should now be out of any other write domains, and we can update
4347          * the domain values for our changes.
4348          */
4349         obj->base.write_domain = 0;
4350         obj->base.read_domains |= I915_GEM_DOMAIN_GTT;
4351
4352         trace_i915_gem_object_change_domain(obj,
4353                                             old_read_domains,
4354                                             old_write_domain);
4355
4356         return 0;
4357
4358 err_unpin_display:
4359         obj->pin_display--;
4360         return ret;
4361 }
4362
4363 void
4364 i915_gem_object_unpin_from_display_plane(struct drm_i915_gem_object *obj,
4365                                          const struct i915_ggtt_view *view)
4366 {
4367         if (WARN_ON(obj->pin_display == 0))
4368                 return;
4369
4370         i915_gem_object_ggtt_unpin_view(obj, view);
4371
4372         obj->pin_display--;
4373 }
4374
4375 /**
4376  * Moves a single object to the CPU read, and possibly write domain.
4377  * @obj: object to act on
4378  * @write: requesting write or read-only access
4379  *
4380  * This function returns when the move is complete, including waiting on
4381  * flushes to occur.
4382  */
4383 int
4384 i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj, bool write)
4385 {
4386         uint32_t old_write_domain, old_read_domains;
4387         int ret;
4388
4389         if (obj->base.write_domain == I915_GEM_DOMAIN_CPU)
4390                 return 0;
4391
4392         ret = i915_gem_object_wait_rendering(obj, !write);
4393         if (ret)
4394                 return ret;
4395
4396         i915_gem_object_flush_gtt_write_domain(obj);
4397
4398         old_write_domain = obj->base.write_domain;
4399         old_read_domains = obj->base.read_domains;
4400
4401         /* Flush the CPU cache if it's still invalid. */
4402         if ((obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0) {
4403                 i915_gem_clflush_object(obj, false);
4404
4405                 obj->base.read_domains |= I915_GEM_DOMAIN_CPU;
4406         }
4407
4408         /* It should now be out of any other write domains, and we can update
4409          * the domain values for our changes.
4410          */
4411         BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_CPU) != 0);
4412
4413         /* If we're writing through the CPU, then the GPU read domains will
4414          * need to be invalidated at next use.
4415          */
4416         if (write) {
4417                 obj->base.read_domains = I915_GEM_DOMAIN_CPU;
4418                 obj->base.write_domain = I915_GEM_DOMAIN_CPU;
4419         }
4420
4421         trace_i915_gem_object_change_domain(obj,
4422                                             old_read_domains,
4423                                             old_write_domain);
4424
4425         return 0;
4426 }
4427
4428 /* Throttle our rendering by waiting until the ring has completed our requests
4429  * emitted over 20 msec ago.
4430  *
4431  * Note that if we were to use the current jiffies each time around the loop,
4432  * we wouldn't escape the function with any frames outstanding if the time to
4433  * render a frame was over 20ms.
4434  *
4435  * This should get us reasonable parallelism between CPU and GPU but also
4436  * relatively low latency when blocking on a particular request to finish.
4437  */
4438 static int
4439 i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file)
4440 {
4441         struct drm_i915_private *dev_priv = to_i915(dev);
4442         struct drm_i915_file_private *file_priv = file->driver_priv;
4443         unsigned long recent_enough = jiffies - DRM_I915_THROTTLE_JIFFIES;
4444         struct drm_i915_gem_request *request, *target = NULL;
4445         int ret;
4446
4447         ret = i915_gem_wait_for_error(&dev_priv->gpu_error);
4448         if (ret)
4449                 return ret;
4450
4451         /* ABI: return -EIO if already wedged */
4452         if (i915_terminally_wedged(&dev_priv->gpu_error))
4453                 return -EIO;
4454
4455         spin_lock(&file_priv->mm.lock);
4456         list_for_each_entry(request, &file_priv->mm.request_list, client_list) {
4457                 if (time_after_eq(request->emitted_jiffies, recent_enough))
4458                         break;
4459
4460                 /*
4461                  * Note that the request might not have been submitted yet.
4462                  * In which case emitted_jiffies will be zero.
4463                  */
4464                 if (!request->emitted_jiffies)
4465                         continue;
4466
4467                 target = request;
4468         }
4469         if (target)
4470                 i915_gem_request_reference(target);
4471         spin_unlock(&file_priv->mm.lock);
4472
4473         if (target == NULL)
4474                 return 0;
4475
4476         ret = __i915_wait_request(target, true, NULL, NULL);
4477         i915_gem_request_unreference(target);
4478
4479         return ret;
4480 }
4481
4482 static bool
4483 i915_vma_misplaced(struct i915_vma *vma, uint32_t alignment, uint64_t flags)
4484 {
4485         struct drm_i915_gem_object *obj = vma->obj;
4486
4487         if (alignment &&
4488             vma->node.start & (alignment - 1))
4489                 return true;
4490
4491         if (flags & PIN_MAPPABLE && !obj->map_and_fenceable)
4492                 return true;
4493
4494         if (flags & PIN_OFFSET_BIAS &&
4495             vma->node.start < (flags & PIN_OFFSET_MASK))
4496                 return true;
4497
4498         if (flags & PIN_OFFSET_FIXED &&
4499             vma->node.start != (flags & PIN_OFFSET_MASK))
4500                 return true;
4501
4502         return false;
4503 }
4504
4505 void __i915_vma_set_map_and_fenceable(struct i915_vma *vma)
4506 {
4507         struct drm_i915_gem_object *obj = vma->obj;
4508         bool mappable, fenceable;
4509         u32 fence_size, fence_alignment;
4510
4511         fence_size = i915_gem_get_gtt_size(obj->base.dev,
4512                                            obj->base.size,
4513                                            obj->tiling_mode);
4514         fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
4515                                                      obj->base.size,
4516                                                      obj->tiling_mode,
4517                                                      true);
4518
4519         fenceable = (vma->node.size == fence_size &&
4520                      (vma->node.start & (fence_alignment - 1)) == 0);
4521
4522         mappable = (vma->node.start + fence_size <=
4523                     to_i915(obj->base.dev)->ggtt.mappable_end);
4524
4525         obj->map_and_fenceable = mappable && fenceable;
4526 }
4527
4528 static int
4529 i915_gem_object_do_pin(struct drm_i915_gem_object *obj,
4530                        struct i915_address_space *vm,
4531                        const struct i915_ggtt_view *ggtt_view,
4532                        uint32_t alignment,
4533                        uint64_t flags)
4534 {
4535         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
4536         struct i915_vma *vma;
4537         unsigned bound;
4538         int ret;
4539
4540         if (WARN_ON(vm == &dev_priv->mm.aliasing_ppgtt->base))
4541                 return -ENODEV;
4542
4543         if (WARN_ON(flags & (PIN_GLOBAL | PIN_MAPPABLE) && !i915_is_ggtt(vm)))
4544                 return -EINVAL;
4545
4546         if (WARN_ON((flags & (PIN_MAPPABLE | PIN_GLOBAL)) == PIN_MAPPABLE))
4547                 return -EINVAL;
4548
4549         if (WARN_ON(i915_is_ggtt(vm) != !!ggtt_view))
4550                 return -EINVAL;
4551
4552         vma = ggtt_view ? i915_gem_obj_to_ggtt_view(obj, ggtt_view) :
4553                           i915_gem_obj_to_vma(obj, vm);
4554
4555         if (vma) {
4556                 if (WARN_ON(vma->pin_count == DRM_I915_GEM_OBJECT_MAX_PIN_COUNT))
4557                         return -EBUSY;
4558
4559                 if (i915_vma_misplaced(vma, alignment, flags)) {
4560                         WARN(vma->pin_count,
4561                              "bo is already pinned in %s with incorrect alignment:"
4562                              " offset=%08x %08x, req.alignment=%x, req.map_and_fenceable=%d,"
4563                              " obj->map_and_fenceable=%d\n",
4564                              ggtt_view ? "ggtt" : "ppgtt",
4565                              upper_32_bits(vma->node.start),
4566                              lower_32_bits(vma->node.start),
4567                              alignment,
4568                              !!(flags & PIN_MAPPABLE),
4569                              obj->map_and_fenceable);
4570                         ret = i915_vma_unbind(vma);
4571                         if (ret)
4572                                 return ret;
4573
4574                         vma = NULL;
4575                 }
4576         }
4577
4578         bound = vma ? vma->bound : 0;
4579         if (vma == NULL || !drm_mm_node_allocated(&vma->node)) {
4580                 vma = i915_gem_object_bind_to_vm(obj, vm, ggtt_view, alignment,
4581                                                  flags);
4582                 if (IS_ERR(vma))
4583                         return PTR_ERR(vma);
4584         } else {
4585                 ret = i915_vma_bind(vma, obj->cache_level, flags);
4586                 if (ret)
4587                         return ret;
4588         }
4589
4590         if (ggtt_view && ggtt_view->type == I915_GGTT_VIEW_NORMAL &&
4591             (bound ^ vma->bound) & GLOBAL_BIND) {
4592                 __i915_vma_set_map_and_fenceable(vma);
4593                 WARN_ON(flags & PIN_MAPPABLE && !obj->map_and_fenceable);
4594         }
4595
4596         vma->pin_count++;
4597         return 0;
4598 }
4599
4600 int
4601 i915_gem_object_pin(struct drm_i915_gem_object *obj,
4602                     struct i915_address_space *vm,
4603                     uint32_t alignment,
4604                     uint64_t flags)
4605 {
4606         return i915_gem_object_do_pin(obj, vm,
4607                                       i915_is_ggtt(vm) ? &i915_ggtt_view_normal : NULL,
4608                                       alignment, flags);
4609 }
4610
4611 int
4612 i915_gem_object_ggtt_pin(struct drm_i915_gem_object *obj,
4613                          const struct i915_ggtt_view *view,
4614                          uint32_t alignment,
4615                          uint64_t flags)
4616 {
4617         struct drm_device *dev = obj->base.dev;
4618         struct drm_i915_private *dev_priv = to_i915(dev);
4619         struct i915_ggtt *ggtt = &dev_priv->ggtt;
4620
4621         BUG_ON(!view);
4622
4623         return i915_gem_object_do_pin(obj, &ggtt->base, view,
4624                                       alignment, flags | PIN_GLOBAL);
4625 }
4626
4627 void
4628 i915_gem_object_ggtt_unpin_view(struct drm_i915_gem_object *obj,
4629                                 const struct i915_ggtt_view *view)
4630 {
4631         struct i915_vma *vma = i915_gem_obj_to_ggtt_view(obj, view);
4632
4633         WARN_ON(vma->pin_count == 0);
4634         WARN_ON(!i915_gem_obj_ggtt_bound_view(obj, view));
4635
4636         --vma->pin_count;
4637 }
4638
4639 int
4640 i915_gem_busy_ioctl(struct drm_device *dev, void *data,
4641                     struct drm_file *file)
4642 {
4643         struct drm_i915_gem_busy *args = data;
4644         struct drm_i915_gem_object *obj;
4645         int ret;
4646
4647         ret = i915_mutex_lock_interruptible(dev);
4648         if (ret)
4649                 return ret;
4650
4651         obj = to_intel_bo(drm_gem_object_lookup(file, args->handle));
4652         if (&obj->base == NULL) {
4653                 ret = -ENOENT;
4654                 goto unlock;
4655         }
4656
4657         /* Count all active objects as busy, even if they are currently not used
4658          * by the gpu. Users of this interface expect objects to eventually
4659          * become non-busy without any further actions, therefore emit any
4660          * necessary flushes here.
4661          */
4662         ret = i915_gem_object_flush_active(obj);
4663         if (ret)
4664                 goto unref;
4665
4666         args->busy = 0;
4667         if (obj->active) {
4668                 int i;
4669
4670                 for (i = 0; i < I915_NUM_ENGINES; i++) {
4671                         struct drm_i915_gem_request *req;
4672
4673                         req = obj->last_read_req[i];
4674                         if (req)
4675                                 args->busy |= 1 << (16 + req->engine->exec_id);
4676                 }
4677                 if (obj->last_write_req)
4678                         args->busy |= obj->last_write_req->engine->exec_id;
4679         }
4680
4681 unref:
4682         drm_gem_object_unreference(&obj->base);
4683 unlock:
4684         mutex_unlock(&dev->struct_mutex);
4685         return ret;
4686 }
4687
4688 int
4689 i915_gem_throttle_ioctl(struct drm_device *dev, void *data,
4690                         struct drm_file *file_priv)
4691 {
4692         return i915_gem_ring_throttle(dev, file_priv);
4693 }
4694
4695 int
4696 i915_gem_madvise_ioctl(struct drm_device *dev, void *data,
4697                        struct drm_file *file_priv)
4698 {
4699         struct drm_i915_private *dev_priv = to_i915(dev);
4700         struct drm_i915_gem_madvise *args = data;
4701         struct drm_i915_gem_object *obj;
4702         int ret;
4703
4704         switch (args->madv) {
4705         case I915_MADV_DONTNEED:
4706         case I915_MADV_WILLNEED:
4707             break;
4708         default:
4709             return -EINVAL;
4710         }
4711
4712         ret = i915_mutex_lock_interruptible(dev);
4713         if (ret)
4714                 return ret;
4715
4716         obj = to_intel_bo(drm_gem_object_lookup(file_priv, args->handle));
4717         if (&obj->base == NULL) {
4718                 ret = -ENOENT;
4719                 goto unlock;
4720         }
4721
4722         if (i915_gem_obj_is_pinned(obj)) {
4723                 ret = -EINVAL;
4724                 goto out;
4725         }
4726
4727         if (obj->pages &&
4728             obj->tiling_mode != I915_TILING_NONE &&
4729             dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES) {
4730                 if (obj->madv == I915_MADV_WILLNEED)
4731                         i915_gem_object_unpin_pages(obj);
4732                 if (args->madv == I915_MADV_WILLNEED)
4733                         i915_gem_object_pin_pages(obj);
4734         }
4735
4736         if (obj->madv != __I915_MADV_PURGED)
4737                 obj->madv = args->madv;
4738
4739         /* if the object is no longer attached, discard its backing storage */
4740         if (obj->madv == I915_MADV_DONTNEED && obj->pages == NULL)
4741                 i915_gem_object_truncate(obj);
4742
4743         args->retained = obj->madv != __I915_MADV_PURGED;
4744
4745 out:
4746         drm_gem_object_unreference(&obj->base);
4747 unlock:
4748         mutex_unlock(&dev->struct_mutex);
4749         return ret;
4750 }
4751
4752 void i915_gem_object_init(struct drm_i915_gem_object *obj,
4753                           const struct drm_i915_gem_object_ops *ops)
4754 {
4755         int i;
4756
4757         INIT_LIST_HEAD(&obj->global_list);
4758         for (i = 0; i < I915_NUM_ENGINES; i++)
4759                 INIT_LIST_HEAD(&obj->engine_list[i]);
4760         INIT_LIST_HEAD(&obj->obj_exec_link);
4761         INIT_LIST_HEAD(&obj->vma_list);
4762         INIT_LIST_HEAD(&obj->batch_pool_link);
4763
4764         obj->ops = ops;
4765
4766         obj->fence_reg = I915_FENCE_REG_NONE;
4767         obj->madv = I915_MADV_WILLNEED;
4768
4769         i915_gem_info_add_obj(to_i915(obj->base.dev), obj->base.size);
4770 }
4771
4772 static const struct drm_i915_gem_object_ops i915_gem_object_ops = {
4773         .flags = I915_GEM_OBJECT_HAS_STRUCT_PAGE,
4774         .get_pages = i915_gem_object_get_pages_gtt,
4775         .put_pages = i915_gem_object_put_pages_gtt,
4776 };
4777
4778 struct drm_i915_gem_object *i915_gem_object_create(struct drm_device *dev,
4779                                                   size_t size)
4780 {
4781         struct drm_i915_gem_object *obj;
4782         struct address_space *mapping;
4783         gfp_t mask;
4784         int ret;
4785
4786         obj = i915_gem_object_alloc(dev);
4787         if (obj == NULL)
4788                 return ERR_PTR(-ENOMEM);
4789
4790         ret = drm_gem_object_init(dev, &obj->base, size);
4791         if (ret)
4792                 goto fail;
4793
4794         mask = GFP_HIGHUSER | __GFP_RECLAIMABLE;
4795         if (IS_CRESTLINE(dev) || IS_BROADWATER(dev)) {
4796                 /* 965gm cannot relocate objects above 4GiB. */
4797                 mask &= ~__GFP_HIGHMEM;
4798                 mask |= __GFP_DMA32;
4799         }
4800
4801         mapping = obj->base.filp->f_mapping;
4802         mapping_set_gfp_mask(mapping, mask);
4803
4804         i915_gem_object_init(obj, &i915_gem_object_ops);
4805
4806         obj->base.write_domain = I915_GEM_DOMAIN_CPU;
4807         obj->base.read_domains = I915_GEM_DOMAIN_CPU;
4808
4809         if (HAS_LLC(dev)) {
4810                 /* On some devices, we can have the GPU use the LLC (the CPU
4811                  * cache) for about a 10% performance improvement
4812                  * compared to uncached.  Graphics requests other than
4813                  * display scanout are coherent with the CPU in
4814                  * accessing this cache.  This means in this mode we
4815                  * don't need to clflush on the CPU side, and on the
4816                  * GPU side we only need to flush internal caches to
4817                  * get data visible to the CPU.
4818                  *
4819                  * However, we maintain the display planes as UC, and so
4820                  * need to rebind when first used as such.
4821                  */
4822                 obj->cache_level = I915_CACHE_LLC;
4823         } else
4824                 obj->cache_level = I915_CACHE_NONE;
4825
4826         trace_i915_gem_object_create(obj);
4827
4828         return obj;
4829
4830 fail:
4831         i915_gem_object_free(obj);
4832
4833         return ERR_PTR(ret);
4834 }
4835
4836 static bool discard_backing_storage(struct drm_i915_gem_object *obj)
4837 {
4838         /* If we are the last user of the backing storage (be it shmemfs
4839          * pages or stolen etc), we know that the pages are going to be
4840          * immediately released. In this case, we can then skip copying
4841          * back the contents from the GPU.
4842          */
4843
4844         if (obj->madv != I915_MADV_WILLNEED)
4845                 return false;
4846
4847         if (obj->base.filp == NULL)
4848                 return true;
4849
4850         /* At first glance, this looks racy, but then again so would be
4851          * userspace racing mmap against close. However, the first external
4852          * reference to the filp can only be obtained through the
4853          * i915_gem_mmap_ioctl() which safeguards us against the user
4854          * acquiring such a reference whilst we are in the middle of
4855          * freeing the object.
4856          */
4857         return atomic_long_read(&obj->base.filp->f_count) == 1;
4858 }
4859
4860 void i915_gem_free_object(struct drm_gem_object *gem_obj)
4861 {
4862         struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
4863         struct drm_device *dev = obj->base.dev;
4864         struct drm_i915_private *dev_priv = to_i915(dev);
4865         struct i915_vma *vma, *next;
4866
4867         intel_runtime_pm_get(dev_priv);
4868
4869         trace_i915_gem_object_destroy(obj);
4870
4871         list_for_each_entry_safe(vma, next, &obj->vma_list, obj_link) {
4872                 int ret;
4873
4874                 vma->pin_count = 0;
4875                 ret = i915_vma_unbind(vma);
4876                 if (WARN_ON(ret == -ERESTARTSYS)) {
4877                         bool was_interruptible;
4878
4879                         was_interruptible = dev_priv->mm.interruptible;
4880                         dev_priv->mm.interruptible = false;
4881
4882                         WARN_ON(i915_vma_unbind(vma));
4883
4884                         dev_priv->mm.interruptible = was_interruptible;
4885                 }
4886         }
4887
4888         /* Stolen objects don't hold a ref, but do hold pin count. Fix that up
4889          * before progressing. */
4890         if (obj->stolen)
4891                 i915_gem_object_unpin_pages(obj);
4892
4893         WARN_ON(obj->frontbuffer_bits);
4894
4895         if (obj->pages && obj->madv == I915_MADV_WILLNEED &&
4896             dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES &&
4897             obj->tiling_mode != I915_TILING_NONE)
4898                 i915_gem_object_unpin_pages(obj);
4899
4900         if (WARN_ON(obj->pages_pin_count))
4901                 obj->pages_pin_count = 0;
4902         if (discard_backing_storage(obj))
4903                 obj->madv = I915_MADV_DONTNEED;
4904         i915_gem_object_put_pages(obj);
4905         i915_gem_object_free_mmap_offset(obj);
4906
4907         BUG_ON(obj->pages);
4908
4909         if (obj->base.import_attach)
4910                 drm_prime_gem_destroy(&obj->base, NULL);
4911
4912         if (obj->ops->release)
4913                 obj->ops->release(obj);
4914
4915         drm_gem_object_release(&obj->base);
4916         i915_gem_info_remove_obj(dev_priv, obj->base.size);
4917
4918         kfree(obj->bit_17);
4919         i915_gem_object_free(obj);
4920
4921         intel_runtime_pm_put(dev_priv);
4922 }
4923
4924 struct i915_vma *i915_gem_obj_to_vma(struct drm_i915_gem_object *obj,
4925                                      struct i915_address_space *vm)
4926 {
4927         struct i915_vma *vma;
4928         list_for_each_entry(vma, &obj->vma_list, obj_link) {
4929                 if (vma->ggtt_view.type == I915_GGTT_VIEW_NORMAL &&
4930                     vma->vm == vm)
4931                         return vma;
4932         }
4933         return NULL;
4934 }
4935
4936 struct i915_vma *i915_gem_obj_to_ggtt_view(struct drm_i915_gem_object *obj,
4937                                            const struct i915_ggtt_view *view)
4938 {
4939         struct i915_vma *vma;
4940
4941         GEM_BUG_ON(!view);
4942
4943         list_for_each_entry(vma, &obj->vma_list, obj_link)
4944                 if (vma->is_ggtt && i915_ggtt_view_equal(&vma->ggtt_view, view))
4945                         return vma;
4946         return NULL;
4947 }
4948
4949 void i915_gem_vma_destroy(struct i915_vma *vma)
4950 {
4951         WARN_ON(vma->node.allocated);
4952
4953         /* Keep the vma as a placeholder in the execbuffer reservation lists */
4954         if (!list_empty(&vma->exec_list))
4955                 return;
4956
4957         if (!vma->is_ggtt)
4958                 i915_ppgtt_put(i915_vm_to_ppgtt(vma->vm));
4959
4960         list_del(&vma->obj_link);
4961
4962         kmem_cache_free(to_i915(vma->obj->base.dev)->vmas, vma);
4963 }
4964
4965 static void
4966 i915_gem_stop_engines(struct drm_device *dev)
4967 {
4968         struct drm_i915_private *dev_priv = to_i915(dev);
4969         struct intel_engine_cs *engine;
4970
4971         for_each_engine(engine, dev_priv)
4972                 dev_priv->gt.stop_engine(engine);
4973 }
4974
4975 int
4976 i915_gem_suspend(struct drm_device *dev)
4977 {
4978         struct drm_i915_private *dev_priv = to_i915(dev);
4979         int ret = 0;
4980
4981         mutex_lock(&dev->struct_mutex);
4982         ret = i915_gem_wait_for_idle(dev_priv);
4983         if (ret)
4984                 goto err;
4985
4986         i915_gem_retire_requests(dev_priv);
4987
4988         i915_gem_stop_engines(dev);
4989         i915_gem_context_lost(dev_priv);
4990         mutex_unlock(&dev->struct_mutex);
4991
4992         cancel_delayed_work_sync(&dev_priv->gpu_error.hangcheck_work);
4993         cancel_delayed_work_sync(&dev_priv->gt.retire_work);
4994         flush_delayed_work(&dev_priv->gt.idle_work);
4995
4996         /* Assert that we sucessfully flushed all the work and
4997          * reset the GPU back to its idle, low power state.
4998          */
4999         WARN_ON(dev_priv->gt.awake);
5000
5001         return 0;
5002
5003 err:
5004         mutex_unlock(&dev->struct_mutex);
5005         return ret;
5006 }
5007
5008 void i915_gem_init_swizzling(struct drm_device *dev)
5009 {
5010         struct drm_i915_private *dev_priv = to_i915(dev);
5011
5012         if (INTEL_INFO(dev)->gen < 5 ||
5013             dev_priv->mm.bit_6_swizzle_x == I915_BIT_6_SWIZZLE_NONE)
5014                 return;
5015
5016         I915_WRITE(DISP_ARB_CTL, I915_READ(DISP_ARB_CTL) |
5017                                  DISP_TILE_SURFACE_SWIZZLING);
5018
5019         if (IS_GEN5(dev))
5020                 return;
5021
5022         I915_WRITE(TILECTL, I915_READ(TILECTL) | TILECTL_SWZCTL);
5023         if (IS_GEN6(dev))
5024                 I915_WRITE(ARB_MODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_SNB));
5025         else if (IS_GEN7(dev))
5026                 I915_WRITE(ARB_MODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_IVB));
5027         else if (IS_GEN8(dev))
5028                 I915_WRITE(GAMTARBMODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_BDW));
5029         else
5030                 BUG();
5031 }
5032
5033 static void init_unused_ring(struct drm_device *dev, u32 base)
5034 {
5035         struct drm_i915_private *dev_priv = to_i915(dev);
5036
5037         I915_WRITE(RING_CTL(base), 0);
5038         I915_WRITE(RING_HEAD(base), 0);
5039         I915_WRITE(RING_TAIL(base), 0);
5040         I915_WRITE(RING_START(base), 0);
5041 }
5042
5043 static void init_unused_rings(struct drm_device *dev)
5044 {
5045         if (IS_I830(dev)) {
5046                 init_unused_ring(dev, PRB1_BASE);
5047                 init_unused_ring(dev, SRB0_BASE);
5048                 init_unused_ring(dev, SRB1_BASE);
5049                 init_unused_ring(dev, SRB2_BASE);
5050                 init_unused_ring(dev, SRB3_BASE);
5051         } else if (IS_GEN2(dev)) {
5052                 init_unused_ring(dev, SRB0_BASE);
5053                 init_unused_ring(dev, SRB1_BASE);
5054         } else if (IS_GEN3(dev)) {
5055                 init_unused_ring(dev, PRB1_BASE);
5056                 init_unused_ring(dev, PRB2_BASE);
5057         }
5058 }
5059
5060 int i915_gem_init_engines(struct drm_device *dev)
5061 {
5062         struct drm_i915_private *dev_priv = to_i915(dev);
5063         int ret;
5064
5065         ret = intel_init_render_ring_buffer(dev);
5066         if (ret)
5067                 return ret;
5068
5069         if (HAS_BSD(dev)) {
5070                 ret = intel_init_bsd_ring_buffer(dev);
5071                 if (ret)
5072                         goto cleanup_render_ring;
5073         }
5074
5075         if (HAS_BLT(dev)) {
5076                 ret = intel_init_blt_ring_buffer(dev);
5077                 if (ret)
5078                         goto cleanup_bsd_ring;
5079         }
5080
5081         if (HAS_VEBOX(dev)) {
5082                 ret = intel_init_vebox_ring_buffer(dev);
5083                 if (ret)
5084                         goto cleanup_blt_ring;
5085         }
5086
5087         if (HAS_BSD2(dev)) {
5088                 ret = intel_init_bsd2_ring_buffer(dev);
5089                 if (ret)
5090                         goto cleanup_vebox_ring;
5091         }
5092
5093         return 0;
5094
5095 cleanup_vebox_ring:
5096         intel_cleanup_engine(&dev_priv->engine[VECS]);
5097 cleanup_blt_ring:
5098         intel_cleanup_engine(&dev_priv->engine[BCS]);
5099 cleanup_bsd_ring:
5100         intel_cleanup_engine(&dev_priv->engine[VCS]);
5101 cleanup_render_ring:
5102         intel_cleanup_engine(&dev_priv->engine[RCS]);
5103
5104         return ret;
5105 }
5106
5107 int
5108 i915_gem_init_hw(struct drm_device *dev)
5109 {
5110         struct drm_i915_private *dev_priv = to_i915(dev);
5111         struct intel_engine_cs *engine;
5112         int ret;
5113
5114         /* Double layer security blanket, see i915_gem_init() */
5115         intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
5116
5117         if (HAS_EDRAM(dev) && INTEL_GEN(dev_priv) < 9)
5118                 I915_WRITE(HSW_IDICR, I915_READ(HSW_IDICR) | IDIHASHMSK(0xf));
5119
5120         if (IS_HASWELL(dev))
5121                 I915_WRITE(MI_PREDICATE_RESULT_2, IS_HSW_GT3(dev) ?
5122                            LOWER_SLICE_ENABLED : LOWER_SLICE_DISABLED);
5123
5124         if (HAS_PCH_NOP(dev)) {
5125                 if (IS_IVYBRIDGE(dev)) {
5126                         u32 temp = I915_READ(GEN7_MSG_CTL);
5127                         temp &= ~(WAIT_FOR_PCH_FLR_ACK | WAIT_FOR_PCH_RESET_ACK);
5128                         I915_WRITE(GEN7_MSG_CTL, temp);
5129                 } else if (INTEL_INFO(dev)->gen >= 7) {
5130                         u32 temp = I915_READ(HSW_NDE_RSTWRN_OPT);
5131                         temp &= ~RESET_PCH_HANDSHAKE_ENABLE;
5132                         I915_WRITE(HSW_NDE_RSTWRN_OPT, temp);
5133                 }
5134         }
5135
5136         i915_gem_init_swizzling(dev);
5137
5138         /*
5139          * At least 830 can leave some of the unused rings
5140          * "active" (ie. head != tail) after resume which
5141          * will prevent c3 entry. Makes sure all unused rings
5142          * are totally idle.
5143          */
5144         init_unused_rings(dev);
5145
5146         BUG_ON(!dev_priv->kernel_context);
5147
5148         ret = i915_ppgtt_init_hw(dev);
5149         if (ret) {
5150                 DRM_ERROR("PPGTT enable HW failed %d\n", ret);
5151                 goto out;
5152         }
5153
5154         /* Need to do basic initialisation of all rings first: */
5155         for_each_engine(engine, dev_priv) {
5156                 ret = engine->init_hw(engine);
5157                 if (ret)
5158                         goto out;
5159         }
5160
5161         intel_mocs_init_l3cc_table(dev);
5162
5163         /* We can't enable contexts until all firmware is loaded */
5164         ret = intel_guc_setup(dev);
5165         if (ret)
5166                 goto out;
5167
5168 out:
5169         intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
5170         return ret;
5171 }
5172
5173 int i915_gem_init(struct drm_device *dev)
5174 {
5175         struct drm_i915_private *dev_priv = to_i915(dev);
5176         int ret;
5177
5178         mutex_lock(&dev->struct_mutex);
5179
5180         if (!i915.enable_execlists) {
5181                 dev_priv->gt.execbuf_submit = i915_gem_ringbuffer_submission;
5182                 dev_priv->gt.init_engines = i915_gem_init_engines;
5183                 dev_priv->gt.cleanup_engine = intel_cleanup_engine;
5184                 dev_priv->gt.stop_engine = intel_stop_engine;
5185         } else {
5186                 dev_priv->gt.execbuf_submit = intel_execlists_submission;
5187                 dev_priv->gt.init_engines = intel_logical_rings_init;
5188                 dev_priv->gt.cleanup_engine = intel_logical_ring_cleanup;
5189                 dev_priv->gt.stop_engine = intel_logical_ring_stop;
5190         }
5191
5192         /* This is just a security blanket to placate dragons.
5193          * On some systems, we very sporadically observe that the first TLBs
5194          * used by the CS may be stale, despite us poking the TLB reset. If
5195          * we hold the forcewake during initialisation these problems
5196          * just magically go away.
5197          */
5198         intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
5199
5200         i915_gem_init_userptr(dev_priv);
5201         i915_gem_init_ggtt(dev);
5202
5203         ret = i915_gem_context_init(dev);
5204         if (ret)
5205                 goto out_unlock;
5206
5207         ret = dev_priv->gt.init_engines(dev);
5208         if (ret)
5209                 goto out_unlock;
5210
5211         ret = i915_gem_init_hw(dev);
5212         if (ret == -EIO) {
5213                 /* Allow ring initialisation to fail by marking the GPU as
5214                  * wedged. But we only want to do this where the GPU is angry,
5215                  * for all other failure, such as an allocation failure, bail.
5216                  */
5217                 DRM_ERROR("Failed to initialize GPU, declaring it wedged\n");
5218                 atomic_or(I915_WEDGED, &dev_priv->gpu_error.reset_counter);
5219                 ret = 0;
5220         }
5221
5222 out_unlock:
5223         intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
5224         mutex_unlock(&dev->struct_mutex);
5225
5226         return ret;
5227 }
5228
5229 void
5230 i915_gem_cleanup_engines(struct drm_device *dev)
5231 {
5232         struct drm_i915_private *dev_priv = to_i915(dev);
5233         struct intel_engine_cs *engine;
5234
5235         for_each_engine(engine, dev_priv)
5236                 dev_priv->gt.cleanup_engine(engine);
5237 }
5238
5239 static void
5240 init_engine_lists(struct intel_engine_cs *engine)
5241 {
5242         INIT_LIST_HEAD(&engine->active_list);
5243         INIT_LIST_HEAD(&engine->request_list);
5244 }
5245
5246 void
5247 i915_gem_load_init_fences(struct drm_i915_private *dev_priv)
5248 {
5249         struct drm_device *dev = &dev_priv->drm;
5250
5251         if (INTEL_INFO(dev_priv)->gen >= 7 && !IS_VALLEYVIEW(dev_priv) &&
5252             !IS_CHERRYVIEW(dev_priv))
5253                 dev_priv->num_fence_regs = 32;
5254         else if (INTEL_INFO(dev_priv)->gen >= 4 || IS_I945G(dev_priv) ||
5255                  IS_I945GM(dev_priv) || IS_G33(dev_priv))
5256                 dev_priv->num_fence_regs = 16;
5257         else
5258                 dev_priv->num_fence_regs = 8;
5259
5260         if (intel_vgpu_active(dev_priv))
5261                 dev_priv->num_fence_regs =
5262                                 I915_READ(vgtif_reg(avail_rs.fence_num));
5263
5264         /* Initialize fence registers to zero */
5265         i915_gem_restore_fences(dev);
5266
5267         i915_gem_detect_bit_6_swizzle(dev);
5268 }
5269
5270 void
5271 i915_gem_load_init(struct drm_device *dev)
5272 {
5273         struct drm_i915_private *dev_priv = to_i915(dev);
5274         int i;
5275
5276         dev_priv->objects =
5277                 kmem_cache_create("i915_gem_object",
5278                                   sizeof(struct drm_i915_gem_object), 0,
5279                                   SLAB_HWCACHE_ALIGN,
5280                                   NULL);
5281         dev_priv->vmas =
5282                 kmem_cache_create("i915_gem_vma",
5283                                   sizeof(struct i915_vma), 0,
5284                                   SLAB_HWCACHE_ALIGN,
5285                                   NULL);
5286         dev_priv->requests =
5287                 kmem_cache_create("i915_gem_request",
5288                                   sizeof(struct drm_i915_gem_request), 0,
5289                                   SLAB_HWCACHE_ALIGN,
5290                                   NULL);
5291
5292         INIT_LIST_HEAD(&dev_priv->vm_list);
5293         INIT_LIST_HEAD(&dev_priv->context_list);
5294         INIT_LIST_HEAD(&dev_priv->mm.unbound_list);
5295         INIT_LIST_HEAD(&dev_priv->mm.bound_list);
5296         INIT_LIST_HEAD(&dev_priv->mm.fence_list);
5297         for (i = 0; i < I915_NUM_ENGINES; i++)
5298                 init_engine_lists(&dev_priv->engine[i]);
5299         for (i = 0; i < I915_MAX_NUM_FENCES; i++)
5300                 INIT_LIST_HEAD(&dev_priv->fence_regs[i].lru_list);
5301         INIT_DELAYED_WORK(&dev_priv->gt.retire_work,
5302                           i915_gem_retire_work_handler);
5303         INIT_DELAYED_WORK(&dev_priv->gt.idle_work,
5304                           i915_gem_idle_work_handler);
5305         init_waitqueue_head(&dev_priv->gpu_error.wait_queue);
5306         init_waitqueue_head(&dev_priv->gpu_error.reset_queue);
5307
5308         dev_priv->relative_constants_mode = I915_EXEC_CONSTANTS_REL_GENERAL;
5309
5310         INIT_LIST_HEAD(&dev_priv->mm.fence_list);
5311
5312         init_waitqueue_head(&dev_priv->pending_flip_queue);
5313
5314         dev_priv->mm.interruptible = true;
5315
5316         mutex_init(&dev_priv->fb_tracking.lock);
5317 }
5318
5319 void i915_gem_load_cleanup(struct drm_device *dev)
5320 {
5321         struct drm_i915_private *dev_priv = to_i915(dev);
5322
5323         kmem_cache_destroy(dev_priv->requests);
5324         kmem_cache_destroy(dev_priv->vmas);
5325         kmem_cache_destroy(dev_priv->objects);
5326 }
5327
5328 int i915_gem_freeze_late(struct drm_i915_private *dev_priv)
5329 {
5330         struct drm_i915_gem_object *obj;
5331
5332         /* Called just before we write the hibernation image.
5333          *
5334          * We need to update the domain tracking to reflect that the CPU
5335          * will be accessing all the pages to create and restore from the
5336          * hibernation, and so upon restoration those pages will be in the
5337          * CPU domain.
5338          *
5339          * To make sure the hibernation image contains the latest state,
5340          * we update that state just before writing out the image.
5341          */
5342
5343         list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list) {
5344                 obj->base.read_domains = I915_GEM_DOMAIN_CPU;
5345                 obj->base.write_domain = I915_GEM_DOMAIN_CPU;
5346         }
5347
5348         list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
5349                 obj->base.read_domains = I915_GEM_DOMAIN_CPU;
5350                 obj->base.write_domain = I915_GEM_DOMAIN_CPU;
5351         }
5352
5353         return 0;
5354 }
5355
5356 void i915_gem_release(struct drm_device *dev, struct drm_file *file)
5357 {
5358         struct drm_i915_file_private *file_priv = file->driver_priv;
5359
5360         /* Clean up our request list when the client is going away, so that
5361          * later retire_requests won't dereference our soon-to-be-gone
5362          * file_priv.
5363          */
5364         spin_lock(&file_priv->mm.lock);
5365         while (!list_empty(&file_priv->mm.request_list)) {
5366                 struct drm_i915_gem_request *request;
5367
5368                 request = list_first_entry(&file_priv->mm.request_list,
5369                                            struct drm_i915_gem_request,
5370                                            client_list);
5371                 list_del(&request->client_list);
5372                 request->file_priv = NULL;
5373         }
5374         spin_unlock(&file_priv->mm.lock);
5375
5376         if (!list_empty(&file_priv->rps.link)) {
5377                 spin_lock(&to_i915(dev)->rps.client_lock);
5378                 list_del(&file_priv->rps.link);
5379                 spin_unlock(&to_i915(dev)->rps.client_lock);
5380         }
5381 }
5382
5383 int i915_gem_open(struct drm_device *dev, struct drm_file *file)
5384 {
5385         struct drm_i915_file_private *file_priv;
5386         int ret;
5387
5388         DRM_DEBUG_DRIVER("\n");
5389
5390         file_priv = kzalloc(sizeof(*file_priv), GFP_KERNEL);
5391         if (!file_priv)
5392                 return -ENOMEM;
5393
5394         file->driver_priv = file_priv;
5395         file_priv->dev_priv = to_i915(dev);
5396         file_priv->file = file;
5397         INIT_LIST_HEAD(&file_priv->rps.link);
5398
5399         spin_lock_init(&file_priv->mm.lock);
5400         INIT_LIST_HEAD(&file_priv->mm.request_list);
5401
5402         file_priv->bsd_ring = -1;
5403
5404         ret = i915_gem_context_open(dev, file);
5405         if (ret)
5406                 kfree(file_priv);
5407
5408         return ret;
5409 }
5410
5411 /**
5412  * i915_gem_track_fb - update frontbuffer tracking
5413  * @old: current GEM buffer for the frontbuffer slots
5414  * @new: new GEM buffer for the frontbuffer slots
5415  * @frontbuffer_bits: bitmask of frontbuffer slots
5416  *
5417  * This updates the frontbuffer tracking bits @frontbuffer_bits by clearing them
5418  * from @old and setting them in @new. Both @old and @new can be NULL.
5419  */
5420 void i915_gem_track_fb(struct drm_i915_gem_object *old,
5421                        struct drm_i915_gem_object *new,
5422                        unsigned frontbuffer_bits)
5423 {
5424         if (old) {
5425                 WARN_ON(!mutex_is_locked(&old->base.dev->struct_mutex));
5426                 WARN_ON(!(old->frontbuffer_bits & frontbuffer_bits));
5427                 old->frontbuffer_bits &= ~frontbuffer_bits;
5428         }
5429
5430         if (new) {
5431                 WARN_ON(!mutex_is_locked(&new->base.dev->struct_mutex));
5432                 WARN_ON(new->frontbuffer_bits & frontbuffer_bits);
5433                 new->frontbuffer_bits |= frontbuffer_bits;
5434         }
5435 }
5436
5437 /* All the new VM stuff */
5438 u64 i915_gem_obj_offset(struct drm_i915_gem_object *o,
5439                         struct i915_address_space *vm)
5440 {
5441         struct drm_i915_private *dev_priv = to_i915(o->base.dev);
5442         struct i915_vma *vma;
5443
5444         WARN_ON(vm == &dev_priv->mm.aliasing_ppgtt->base);
5445
5446         list_for_each_entry(vma, &o->vma_list, obj_link) {
5447                 if (vma->is_ggtt &&
5448                     vma->ggtt_view.type != I915_GGTT_VIEW_NORMAL)
5449                         continue;
5450                 if (vma->vm == vm)
5451                         return vma->node.start;
5452         }
5453
5454         WARN(1, "%s vma for this object not found.\n",
5455              i915_is_ggtt(vm) ? "global" : "ppgtt");
5456         return -1;
5457 }
5458
5459 u64 i915_gem_obj_ggtt_offset_view(struct drm_i915_gem_object *o,
5460                                   const struct i915_ggtt_view *view)
5461 {
5462         struct i915_vma *vma;
5463
5464         list_for_each_entry(vma, &o->vma_list, obj_link)
5465                 if (vma->is_ggtt && i915_ggtt_view_equal(&vma->ggtt_view, view))
5466                         return vma->node.start;
5467
5468         WARN(1, "global vma for this object not found. (view=%u)\n", view->type);
5469         return -1;
5470 }
5471
5472 bool i915_gem_obj_bound(struct drm_i915_gem_object *o,
5473                         struct i915_address_space *vm)
5474 {
5475         struct i915_vma *vma;
5476
5477         list_for_each_entry(vma, &o->vma_list, obj_link) {
5478                 if (vma->is_ggtt &&
5479                     vma->ggtt_view.type != I915_GGTT_VIEW_NORMAL)
5480                         continue;
5481                 if (vma->vm == vm && drm_mm_node_allocated(&vma->node))
5482                         return true;
5483         }
5484
5485         return false;
5486 }
5487
5488 bool i915_gem_obj_ggtt_bound_view(struct drm_i915_gem_object *o,
5489                                   const struct i915_ggtt_view *view)
5490 {
5491         struct i915_vma *vma;
5492
5493         list_for_each_entry(vma, &o->vma_list, obj_link)
5494                 if (vma->is_ggtt &&
5495                     i915_ggtt_view_equal(&vma->ggtt_view, view) &&
5496                     drm_mm_node_allocated(&vma->node))
5497                         return true;
5498
5499         return false;
5500 }
5501
5502 bool i915_gem_obj_bound_any(struct drm_i915_gem_object *o)
5503 {
5504         struct i915_vma *vma;
5505
5506         list_for_each_entry(vma, &o->vma_list, obj_link)
5507                 if (drm_mm_node_allocated(&vma->node))
5508                         return true;
5509
5510         return false;
5511 }
5512
5513 unsigned long i915_gem_obj_ggtt_size(struct drm_i915_gem_object *o)
5514 {
5515         struct i915_vma *vma;
5516
5517         GEM_BUG_ON(list_empty(&o->vma_list));
5518
5519         list_for_each_entry(vma, &o->vma_list, obj_link) {
5520                 if (vma->is_ggtt &&
5521                     vma->ggtt_view.type == I915_GGTT_VIEW_NORMAL)
5522                         return vma->node.size;
5523         }
5524
5525         return 0;
5526 }
5527
5528 bool i915_gem_obj_is_pinned(struct drm_i915_gem_object *obj)
5529 {
5530         struct i915_vma *vma;
5531         list_for_each_entry(vma, &obj->vma_list, obj_link)
5532                 if (vma->pin_count > 0)
5533                         return true;
5534
5535         return false;
5536 }
5537
5538 /* Like i915_gem_object_get_page(), but mark the returned page dirty */
5539 struct page *
5540 i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj, int n)
5541 {
5542         struct page *page;
5543
5544         /* Only default objects have per-page dirty tracking */
5545         if (WARN_ON(!i915_gem_object_has_struct_page(obj)))
5546                 return NULL;
5547
5548         page = i915_gem_object_get_page(obj, n);
5549         set_page_dirty(page);
5550         return page;
5551 }
5552
5553 /* Allocate a new GEM object and fill it with the supplied data */
5554 struct drm_i915_gem_object *
5555 i915_gem_object_create_from_data(struct drm_device *dev,
5556                                  const void *data, size_t size)
5557 {
5558         struct drm_i915_gem_object *obj;
5559         struct sg_table *sg;
5560         size_t bytes;
5561         int ret;
5562
5563         obj = i915_gem_object_create(dev, round_up(size, PAGE_SIZE));
5564         if (IS_ERR(obj))
5565                 return obj;
5566
5567         ret = i915_gem_object_set_to_cpu_domain(obj, true);
5568         if (ret)
5569                 goto fail;
5570
5571         ret = i915_gem_object_get_pages(obj);
5572         if (ret)
5573                 goto fail;
5574
5575         i915_gem_object_pin_pages(obj);
5576         sg = obj->pages;
5577         bytes = sg_copy_from_buffer(sg->sgl, sg->nents, (void *)data, size);
5578         obj->dirty = 1;         /* Backing store is now out of date */
5579         i915_gem_object_unpin_pages(obj);
5580
5581         if (WARN_ON(bytes != size)) {
5582                 DRM_ERROR("Incomplete copy, wrote %zu of %zu", bytes, size);
5583                 ret = -EFAULT;
5584                 goto fail;
5585         }
5586
5587         return obj;
5588
5589 fail:
5590         drm_gem_object_unreference(&obj->base);
5591         return ERR_PTR(ret);
5592 }