drivers/gpu/drm/i915/i915_gem_execbuffer.c

   1 /*
   2  * Copyright © 2008,2010 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 <[email protected]>
  25  *    Chris Wilson <[email protected]>
  26  *
  27  */
  28
  29 #include <linux/dma_remapping.h>
  30 #include <linux/reservation.h>
  31 #include <linux/uaccess.h>
  32
  33 #include <drm/drmP.h>
  34 #include <drm/i915_drm.h>
  35
  36 #include "i915_drv.h"
  37 #include "i915_trace.h"
  38 #include "intel_drv.h"
  39 #include "intel_frontbuffer.h"
  40
  41 #define DBG_USE_CPU_RELOC 0 /* -1 force GTT relocs; 1 force CPU relocs */
  42
  43 #define  __EXEC_OBJECT_HAS_PIN          (1<<31)
  44 #define  __EXEC_OBJECT_HAS_FENCE        (1<<30)
  45 #define  __EXEC_OBJECT_NEEDS_MAP        (1<<29)
  46 #define  __EXEC_OBJECT_NEEDS_BIAS       (1<<28)
  47 #define  __EXEC_OBJECT_INTERNAL_FLAGS (0xf<<28) /* all of the above */
  48
  49 #define BATCH_OFFSET_BIAS (256*1024)
  50
  51 struct i915_execbuffer_params {
  52         struct drm_device               *dev;
  53         struct drm_file                 *file;
  54         struct i915_vma                 *batch;
  55         u32                             dispatch_flags;
  56         u32                             args_batch_start_offset;
  57         struct intel_engine_cs          *engine;
  58         struct i915_gem_context         *ctx;
  59         struct drm_i915_gem_request     *request;
  60 };
  61
  62 struct eb_vmas {
  63         struct drm_i915_private *i915;
  64         struct list_head vmas;
  65         int and;
  66         union {
  67                 struct i915_vma *lut[0];
  68                 struct hlist_head buckets[0];
  69         };
  70 };
  71
  72 static struct eb_vmas *
  73 eb_create(struct drm_i915_private *i915,
  74           struct drm_i915_gem_execbuffer2 *args)
  75 {
  76         struct eb_vmas *eb = NULL;
  77
  78         if (args->flags & I915_EXEC_HANDLE_LUT) {
  79                 unsigned size = args->buffer_count;
  80                 size *= sizeof(struct i915_vma *);
  81                 size += sizeof(struct eb_vmas);
  82                 eb = kmalloc(size, GFP_TEMPORARY | __GFP_NOWARN | __GFP_NORETRY);
  83         }
  84
  85         if (eb == NULL) {
  86                 unsigned size = args->buffer_count;
  87                 unsigned count = PAGE_SIZE / sizeof(struct hlist_head) / 2;
  88                 BUILD_BUG_ON_NOT_POWER_OF_2(PAGE_SIZE / sizeof(struct hlist_head));
  89                 while (count > 2*size)
  90                         count >>= 1;
  91                 eb = kzalloc(count*sizeof(struct hlist_head) +
  92                              sizeof(struct eb_vmas),
  93                              GFP_TEMPORARY);
  94                 if (eb == NULL)
  95                         return eb;
  96
  97                 eb->and = count - 1;
  98         } else
  99                 eb->and = -args->buffer_count;
 100
 101         eb->i915 = i915;
 102         INIT_LIST_HEAD(&eb->vmas);
 103         return eb;
 104 }
 105
 106 static void
 107 eb_reset(struct eb_vmas *eb)
 108 {
 109         if (eb->and >= 0)
 110                 memset(eb->buckets, 0, (eb->and+1)*sizeof(struct hlist_head));
 111 }
 112
 113 static struct i915_vma *
 114 eb_get_batch(struct eb_vmas *eb)
 115 {
 116         struct i915_vma *vma = list_entry(eb->vmas.prev, typeof(*vma), exec_list);
 117
 118         /*
 119          * SNA is doing fancy tricks with compressing batch buffers, which leads
 120          * to negative relocation deltas. Usually that works out ok since the
 121          * relocate address is still positive, except when the batch is placed
 122          * very low in the GTT. Ensure this doesn't happen.
 123          *
 124          * Note that actual hangs have only been observed on gen7, but for
 125          * paranoia do it everywhere.
 126          */
 127         if ((vma->exec_entry->flags & EXEC_OBJECT_PINNED) == 0)
 128                 vma->exec_entry->flags |= __EXEC_OBJECT_NEEDS_BIAS;
 129
 130         return vma;
 131 }
 132
 133 static int
 134 eb_lookup_vmas(struct eb_vmas *eb,
 135                struct drm_i915_gem_exec_object2 *exec,
 136                const struct drm_i915_gem_execbuffer2 *args,
 137                struct i915_address_space *vm,
 138                struct drm_file *file)
 139 {
 140         struct drm_i915_gem_object *obj;
 141         struct list_head objects;
 142         int i, ret;
 143
 144         INIT_LIST_HEAD(&objects);
 145         spin_lock(&file->table_lock);
 146         /* Grab a reference to the object and release the lock so we can lookup
 147          * or create the VMA without using GFP_ATOMIC */
 148         for (i = 0; i < args->buffer_count; i++) {
 149                 obj = to_intel_bo(idr_find(&file->object_idr, exec[i].handle));
 150                 if (obj == NULL) {
 151                         spin_unlock(&file->table_lock);
 152                         DRM_DEBUG("Invalid object handle %d at index %d\n",
 153                                    exec[i].handle, i);
 154                         ret = -ENOENT;
 155                         goto err;
 156                 }
 157
 158                 if (!list_empty(&obj->obj_exec_link)) {
 159                         spin_unlock(&file->table_lock);
 160                         DRM_DEBUG("Object %p [handle %d, index %d] appears more than once in object list\n",
 161                                    obj, exec[i].handle, i);
 162                         ret = -EINVAL;
 163                         goto err;
 164                 }
 165
 166                 i915_gem_object_get(obj);
 167                 list_add_tail(&obj->obj_exec_link, &objects);
 168         }
 169         spin_unlock(&file->table_lock);
 170
 171         i = 0;
 172         while (!list_empty(&objects)) {
 173                 struct i915_vma *vma;
 174
 175                 obj = list_first_entry(&objects,
 176                                        struct drm_i915_gem_object,
 177                                        obj_exec_link);
 178
 179                 /*
 180                  * NOTE: We can leak any vmas created here when something fails
 181                  * later on. But that's no issue since vma_unbind can deal with
 182                  * vmas which are not actually bound. And since only
 183                  * lookup_or_create exists as an interface to get at the vma
 184                  * from the (obj, vm) we don't run the risk of creating
 185                  * duplicated vmas for the same vm.
 186                  */
 187                 vma = i915_vma_instance(obj, vm, NULL);
 188                 if (unlikely(IS_ERR(vma))) {
 189                         DRM_DEBUG("Failed to lookup VMA\n");
 190                         ret = PTR_ERR(vma);
 191                         goto err;
 192                 }
 193
 194                 /* Transfer ownership from the objects list to the vmas list. */
 195                 list_add_tail(&vma->exec_list, &eb->vmas);
 196                 list_del_init(&obj->obj_exec_link);
 197
 198                 vma->exec_entry = &exec[i];
 199                 if (eb->and < 0) {
 200                         eb->lut[i] = vma;
 201                 } else {
 202                         uint32_t handle = args->flags & I915_EXEC_HANDLE_LUT ? i : exec[i].handle;
 203                         vma->exec_handle = handle;
 204                         hlist_add_head(&vma->exec_node,
 205                                        &eb->buckets[handle & eb->and]);
 206                 }
 207                 ++i;
 208         }
 209
 210         return 0;
 211
 212
 213 err:
 214         while (!list_empty(&objects)) {
 215                 obj = list_first_entry(&objects,
 216                                        struct drm_i915_gem_object,
 217                                        obj_exec_link);
 218                 list_del_init(&obj->obj_exec_link);
 219                 i915_gem_object_put(obj);
 220         }
 221         /*
 222          * Objects already transfered to the vmas list will be unreferenced by
 223          * eb_destroy.
 224          */
 225
 226         return ret;
 227 }
 228
 229 static struct i915_vma *eb_get_vma(struct eb_vmas *eb, unsigned long handle)
 230 {
 231         if (eb->and < 0) {
 232                 if (handle >= -eb->and)
 233                         return NULL;
 234                 return eb->lut[handle];
 235         } else {
 236                 struct hlist_head *head;
 237                 struct i915_vma *vma;
 238
 239                 head = &eb->buckets[handle & eb->and];
 240                 hlist_for_each_entry(vma, head, exec_node) {
 241                         if (vma->exec_handle == handle)
 242                                 return vma;
 243                 }
 244                 return NULL;
 245         }
 246 }
 247
 248 static void
 249 i915_gem_execbuffer_unreserve_vma(struct i915_vma *vma)
 250 {
 251         struct drm_i915_gem_exec_object2 *entry;
 252
 253         if (!drm_mm_node_allocated(&vma->node))
 254                 return;
 255
 256         entry = vma->exec_entry;
 257
 258         if (entry->flags & __EXEC_OBJECT_HAS_FENCE)
 259                 i915_vma_unpin_fence(vma);
 260
 261         if (entry->flags & __EXEC_OBJECT_HAS_PIN)
 262                 __i915_vma_unpin(vma);
 263
 264         entry->flags &= ~(__EXEC_OBJECT_HAS_FENCE | __EXEC_OBJECT_HAS_PIN);
 265 }
 266
 267 static void eb_destroy(struct eb_vmas *eb)
 268 {
 269         while (!list_empty(&eb->vmas)) {
 270                 struct i915_vma *vma;
 271
 272                 vma = list_first_entry(&eb->vmas,
 273                                        struct i915_vma,
 274                                        exec_list);
 275                 list_del_init(&vma->exec_list);
 276                 i915_gem_execbuffer_unreserve_vma(vma);
 277                 vma->exec_entry = NULL;
 278                 i915_vma_put(vma);
 279         }
 280         kfree(eb);
 281 }
 282
 283 static inline int use_cpu_reloc(struct drm_i915_gem_object *obj)
 284 {
 285         if (!i915_gem_object_has_struct_page(obj))
 286                 return false;
 287
 288         if (DBG_USE_CPU_RELOC)
 289                 return DBG_USE_CPU_RELOC > 0;
 290
 291         return (HAS_LLC(to_i915(obj->base.dev)) ||
 292                 obj->base.write_domain == I915_GEM_DOMAIN_CPU ||
 293                 obj->cache_level != I915_CACHE_NONE);
 294 }
 295
 296 /* Used to convert any address to canonical form.
 297  * Starting from gen8, some commands (e.g. STATE_BASE_ADDRESS,
 298  * MI_LOAD_REGISTER_MEM and others, see Broadwell PRM Vol2a) require the
 299  * addresses to be in a canonical form:
 300  * "GraphicsAddress[63:48] are ignored by the HW and assumed to be in correct
 301  * canonical form [63:48] == [47]."
 302  */
 303 #define GEN8_HIGH_ADDRESS_BIT 47
 304 static inline uint64_t gen8_canonical_addr(uint64_t address)
 305 {
 306         return sign_extend64(address, GEN8_HIGH_ADDRESS_BIT);
 307 }
 308
 309 static inline uint64_t gen8_noncanonical_addr(uint64_t address)
 310 {
 311         return address & ((1ULL << (GEN8_HIGH_ADDRESS_BIT + 1)) - 1);
 312 }
 313
 314 static inline uint64_t
 315 relocation_target(const struct drm_i915_gem_relocation_entry *reloc,
 316                   uint64_t target_offset)
 317 {
 318         return gen8_canonical_addr((int)reloc->delta + target_offset);
 319 }
 320
 321 struct reloc_cache {
 322         struct drm_i915_private *i915;
 323         struct drm_mm_node node;
 324         unsigned long vaddr;
 325         unsigned int page;
 326         bool use_64bit_reloc;
 327 };
 328
 329 static void reloc_cache_init(struct reloc_cache *cache,
 330                              struct drm_i915_private *i915)
 331 {
 332         cache->page = -1;
 333         cache->vaddr = 0;
 334         cache->i915 = i915;
 335         /* Must be a variable in the struct to allow GCC to unroll. */
 336         cache->use_64bit_reloc = HAS_64BIT_RELOC(i915);
 337         cache->node.allocated = false;
 338 }
 339
 340 static inline void *unmask_page(unsigned long p)
 341 {
 342         return (void *)(uintptr_t)(p & PAGE_MASK);
 343 }
 344
 345 static inline unsigned int unmask_flags(unsigned long p)
 346 {
 347         return p & ~PAGE_MASK;
 348 }
 349
 350 #define KMAP 0x4 /* after CLFLUSH_FLAGS */
 351
 352 static void reloc_cache_fini(struct reloc_cache *cache)
 353 {
 354         void *vaddr;
 355
 356         if (!cache->vaddr)
 357                 return;
 358
 359         vaddr = unmask_page(cache->vaddr);
 360         if (cache->vaddr & KMAP) {
 361                 if (cache->vaddr & CLFLUSH_AFTER)
 362                         mb();
 363
 364                 kunmap_atomic(vaddr);
 365                 i915_gem_obj_finish_shmem_access((struct drm_i915_gem_object *)cache->node.mm);
 366         } else {
 367                 wmb();
 368                 io_mapping_unmap_atomic((void __iomem *)vaddr);
 369                 if (cache->node.allocated) {
 370                         struct i915_ggtt *ggtt = &cache->i915->ggtt;
 371
 372                         ggtt->base.clear_range(&ggtt->base,
 373                                                cache->node.start,
 374                                                cache->node.size);
 375                         drm_mm_remove_node(&cache->node);
 376                 } else {
 377                         i915_vma_unpin((struct i915_vma *)cache->node.mm);
 378                 }
 379         }
 380 }
 381
 382 static void *reloc_kmap(struct drm_i915_gem_object *obj,
 383                         struct reloc_cache *cache,
 384                         int page)
 385 {
 386         void *vaddr;
 387
 388         if (cache->vaddr) {
 389                 kunmap_atomic(unmask_page(cache->vaddr));
 390         } else {
 391                 unsigned int flushes;
 392                 int ret;
 393
 394                 ret = i915_gem_obj_prepare_shmem_write(obj, &flushes);
 395                 if (ret)
 396                         return ERR_PTR(ret);
 397
 398                 BUILD_BUG_ON(KMAP & CLFLUSH_FLAGS);
 399                 BUILD_BUG_ON((KMAP | CLFLUSH_FLAGS) & PAGE_MASK);
 400
 401                 cache->vaddr = flushes | KMAP;
 402                 cache->node.mm = (void *)obj;
 403                 if (flushes)
 404                         mb();
 405         }
 406
 407         vaddr = kmap_atomic(i915_gem_object_get_dirty_page(obj, page));
 408         cache->vaddr = unmask_flags(cache->vaddr) | (unsigned long)vaddr;
 409         cache->page = page;
 410
 411         return vaddr;
 412 }
 413
 414 static void *reloc_iomap(struct drm_i915_gem_object *obj,
 415                          struct reloc_cache *cache,
 416                          int page)
 417 {
 418         struct i915_ggtt *ggtt = &cache->i915->ggtt;
 419         unsigned long offset;
 420         void *vaddr;
 421
 422         if (cache->vaddr) {
 423                 io_mapping_unmap_atomic((void __force __iomem *) unmask_page(cache->vaddr));
 424         } else {
 425                 struct i915_vma *vma;
 426                 int ret;
 427
 428                 if (use_cpu_reloc(obj))
 429                         return NULL;
 430
 431                 ret = i915_gem_object_set_to_gtt_domain(obj, true);
 432                 if (ret)
 433                         return ERR_PTR(ret);
 434
 435                 vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
 436                                                PIN_MAPPABLE | PIN_NONBLOCK);
 437                 if (IS_ERR(vma)) {
 438                         memset(&cache->node, 0, sizeof(cache->node));
 439                         ret = drm_mm_insert_node_in_range
 440                                 (&ggtt->base.mm, &cache->node,
 441                                  PAGE_SIZE, 0, I915_COLOR_UNEVICTABLE,
 442                                  0, ggtt->mappable_end,
 443                                  DRM_MM_INSERT_LOW);
 444                         if (ret) /* no inactive aperture space, use cpu reloc */
 445                                 return NULL;
 446                 } else {
 447                         ret = i915_vma_put_fence(vma);
 448                         if (ret) {
 449                                 i915_vma_unpin(vma);
 450                                 return ERR_PTR(ret);
 451                         }
 452
 453                         cache->node.start = vma->node.start;
 454                         cache->node.mm = (void *)vma;
 455                 }
 456         }
 457
 458         offset = cache->node.start;
 459         if (cache->node.allocated) {
 460                 wmb();
 461                 ggtt->base.insert_page(&ggtt->base,
 462                                        i915_gem_object_get_dma_address(obj, page),
 463                                        offset, I915_CACHE_NONE, 0);
 464         } else {
 465                 offset += page << PAGE_SHIFT;
 466         }
 467
 468         vaddr = (void __force *) io_mapping_map_atomic_wc(&cache->i915->ggtt.mappable, offset);
 469         cache->page = page;
 470         cache->vaddr = (unsigned long)vaddr;
 471
 472         return vaddr;
 473 }
 474
 475 static void *reloc_vaddr(struct drm_i915_gem_object *obj,
 476                          struct reloc_cache *cache,
 477                          int page)
 478 {
 479         void *vaddr;
 480
 481         if (cache->page == page) {
 482                 vaddr = unmask_page(cache->vaddr);
 483         } else {
 484                 vaddr = NULL;
 485                 if ((cache->vaddr & KMAP) == 0)
 486                         vaddr = reloc_iomap(obj, cache, page);
 487                 if (!vaddr)
 488                         vaddr = reloc_kmap(obj, cache, page);
 489         }
 490
 491         return vaddr;
 492 }
 493
 494 static void clflush_write32(u32 *addr, u32 value, unsigned int flushes)
 495 {
 496         if (unlikely(flushes & (CLFLUSH_BEFORE | CLFLUSH_AFTER))) {
 497                 if (flushes & CLFLUSH_BEFORE) {
 498                         clflushopt(addr);
 499                         mb();
 500                 }
 501
 502                 *addr = value;
 503
 504                 /* Writes to the same cacheline are serialised by the CPU
 505                  * (including clflush). On the write path, we only require
 506                  * that it hits memory in an orderly fashion and place
 507                  * mb barriers at the start and end of the relocation phase
 508                  * to ensure ordering of clflush wrt to the system.
 509                  */
 510                 if (flushes & CLFLUSH_AFTER)
 511                         clflushopt(addr);
 512         } else
 513                 *addr = value;
 514 }
 515
 516 static int
 517 relocate_entry(struct drm_i915_gem_object *obj,
 518                const struct drm_i915_gem_relocation_entry *reloc,
 519                struct reloc_cache *cache,
 520                u64 target_offset)
 521 {
 522         u64 offset = reloc->offset;
 523         bool wide = cache->use_64bit_reloc;
 524         void *vaddr;
 525
 526         target_offset = relocation_target(reloc, target_offset);
 527 repeat:
 528         vaddr = reloc_vaddr(obj, cache, offset >> PAGE_SHIFT);
 529         if (IS_ERR(vaddr))
 530                 return PTR_ERR(vaddr);
 531
 532         clflush_write32(vaddr + offset_in_page(offset),
 533                         lower_32_bits(target_offset),
 534                         cache->vaddr);
 535
 536         if (wide) {
 537                 offset += sizeof(u32);
 538                 target_offset >>= 32;
 539                 wide = false;
 540                 goto repeat;
 541         }
 542
 543         return 0;
 544 }
 545
 546 static int
 547 i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj,
 548                                    struct eb_vmas *eb,
 549                                    struct drm_i915_gem_relocation_entry *reloc,
 550                                    struct reloc_cache *cache)
 551 {
 552         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
 553         struct drm_gem_object *target_obj;
 554         struct drm_i915_gem_object *target_i915_obj;
 555         struct i915_vma *target_vma;
 556         uint64_t target_offset;
 557         int ret;
 558
 559         /* we've already hold a reference to all valid objects */
 560         target_vma = eb_get_vma(eb, reloc->target_handle);
 561         if (unlikely(target_vma == NULL))
 562                 return -ENOENT;
 563         target_i915_obj = target_vma->obj;
 564         target_obj = &target_vma->obj->base;
 565
 566         target_offset = gen8_canonical_addr(target_vma->node.start);
 567
 568         /* Sandybridge PPGTT errata: We need a global gtt mapping for MI and
 569          * pipe_control writes because the gpu doesn't properly redirect them
 570          * through the ppgtt for non_secure batchbuffers. */
 571         if (unlikely(IS_GEN6(dev_priv) &&
 572             reloc->write_domain == I915_GEM_DOMAIN_INSTRUCTION)) {
 573                 ret = i915_vma_bind(target_vma, target_i915_obj->cache_level,
 574                                     PIN_GLOBAL);
 575                 if (WARN_ONCE(ret, "Unexpected failure to bind target VMA!"))
 576                         return ret;
 577         }
 578
 579         /* Validate that the target is in a valid r/w GPU domain */
 580         if (unlikely(reloc->write_domain & (reloc->write_domain - 1))) {
 581                 DRM_DEBUG("reloc with multiple write domains: "
 582                           "obj %p target %d offset %d "
 583                           "read %08x write %08x",
 584                           obj, reloc->target_handle,
 585                           (int) reloc->offset,
 586                           reloc->read_domains,
 587                           reloc->write_domain);
 588                 return -EINVAL;
 589         }
 590         if (unlikely((reloc->write_domain | reloc->read_domains)
 591                      & ~I915_GEM_GPU_DOMAINS)) {
 592                 DRM_DEBUG("reloc with read/write non-GPU domains: "
 593                           "obj %p target %d offset %d "
 594                           "read %08x write %08x",
 595                           obj, reloc->target_handle,
 596                           (int) reloc->offset,
 597                           reloc->read_domains,
 598                           reloc->write_domain);
 599                 return -EINVAL;
 600         }
 601
 602         target_obj->pending_read_domains |= reloc->read_domains;
 603         target_obj->pending_write_domain |= reloc->write_domain;
 604
 605         /* If the relocation already has the right value in it, no
 606          * more work needs to be done.
 607          */
 608         if (target_offset == reloc->presumed_offset)
 609                 return 0;
 610
 611         /* Check that the relocation address is valid... */
 612         if (unlikely(reloc->offset >
 613                      obj->base.size - (cache->use_64bit_reloc ? 8 : 4))) {
 614                 DRM_DEBUG("Relocation beyond object bounds: "
 615                           "obj %p target %d offset %d size %d.\n",
 616                           obj, reloc->target_handle,
 617                           (int) reloc->offset,
 618                           (int) obj->base.size);
 619                 return -EINVAL;
 620         }
 621         if (unlikely(reloc->offset & 3)) {
 622                 DRM_DEBUG("Relocation not 4-byte aligned: "
 623                           "obj %p target %d offset %d.\n",
 624                           obj, reloc->target_handle,
 625                           (int) reloc->offset);
 626                 return -EINVAL;
 627         }
 628
 629         ret = relocate_entry(obj, reloc, cache, target_offset);
 630         if (ret)
 631                 return ret;
 632
 633         /* and update the user's relocation entry */
 634         reloc->presumed_offset = target_offset;
 635         return 0;
 636 }
 637
 638 static int
 639 i915_gem_execbuffer_relocate_vma(struct i915_vma *vma,
 640                                  struct eb_vmas *eb)
 641 {
 642 #define N_RELOC(x) ((x) / sizeof(struct drm_i915_gem_relocation_entry))
 643         struct drm_i915_gem_relocation_entry stack_reloc[N_RELOC(512)];
 644         struct drm_i915_gem_relocation_entry __user *user_relocs;
 645         struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
 646         struct reloc_cache cache;
 647         int remain, ret = 0;
 648
 649         user_relocs = u64_to_user_ptr(entry->relocs_ptr);
 650         reloc_cache_init(&cache, eb->i915);
 651
 652         remain = entry->relocation_count;
 653         while (remain) {
 654                 struct drm_i915_gem_relocation_entry *r = stack_reloc;
 655                 unsigned long unwritten;
 656                 unsigned int count;
 657
 658                 count = min_t(unsigned int, remain, ARRAY_SIZE(stack_reloc));
 659                 remain -= count;
 660
 661                 /* This is the fast path and we cannot handle a pagefault
 662                  * whilst holding the struct mutex lest the user pass in the
 663                  * relocations contained within a mmaped bo. For in such a case
 664                  * we, the page fault handler would call i915_gem_fault() and
 665                  * we would try to acquire the struct mutex again. Obviously
 666                  * this is bad and so lockdep complains vehemently.
 667                  */
 668                 pagefault_disable();
 669                 unwritten = __copy_from_user_inatomic(r, user_relocs, count*sizeof(r[0]));
 670                 pagefault_enable();
 671                 if (unlikely(unwritten)) {
 672                         ret = -EFAULT;
 673                         goto out;
 674                 }
 675
 676                 do {
 677                         u64 offset = r->presumed_offset;
 678
 679                         ret = i915_gem_execbuffer_relocate_entry(vma->obj, eb, r, &cache);
 680                         if (ret)
 681                                 goto out;
 682
 683                         if (r->presumed_offset != offset) {
 684                                 pagefault_disable();
 685                                 unwritten = __put_user(r->presumed_offset,
 686                                                        &user_relocs->presumed_offset);
 687                                 pagefault_enable();
 688                                 if (unlikely(unwritten)) {
 689                                         /* Note that reporting an error now
 690                                          * leaves everything in an inconsistent
 691                                          * state as we have *already* changed
 692                                          * the relocation value inside the
 693                                          * object. As we have not changed the
 694                                          * reloc.presumed_offset or will not
 695                                          * change the execobject.offset, on the
 696                                          * call we may not rewrite the value
 697                                          * inside the object, leaving it
 698                                          * dangling and causing a GPU hang.
 699                                          */
 700                                         ret = -EFAULT;
 701                                         goto out;
 702                                 }
 703                         }
 704
 705                         user_relocs++;
 706                         r++;
 707                 } while (--count);
 708         }
 709
 710 out:
 711         reloc_cache_fini(&cache);
 712         return ret;
 713 #undef N_RELOC
 714 }
 715
 716 static int
 717 i915_gem_execbuffer_relocate_vma_slow(struct i915_vma *vma,
 718                                       struct eb_vmas *eb,
 719                                       struct drm_i915_gem_relocation_entry *relocs)
 720 {
 721         const struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
 722         struct reloc_cache cache;
 723         int i, ret = 0;
 724
 725         reloc_cache_init(&cache, eb->i915);
 726         for (i = 0; i < entry->relocation_count; i++) {
 727                 ret = i915_gem_execbuffer_relocate_entry(vma->obj, eb, &relocs[i], &cache);
 728                 if (ret)
 729                         break;
 730         }
 731         reloc_cache_fini(&cache);
 732
 733         return ret;
 734 }
 735
 736 static int
 737 i915_gem_execbuffer_relocate(struct eb_vmas *eb)
 738 {
 739         struct i915_vma *vma;
 740         int ret = 0;
 741
 742         list_for_each_entry(vma, &eb->vmas, exec_list) {
 743                 ret = i915_gem_execbuffer_relocate_vma(vma, eb);
 744                 if (ret)
 745                         break;
 746         }
 747
 748         return ret;
 749 }
 750
 751 static bool only_mappable_for_reloc(unsigned int flags)
 752 {
 753         return (flags & (EXEC_OBJECT_NEEDS_FENCE | __EXEC_OBJECT_NEEDS_MAP)) ==
 754                 __EXEC_OBJECT_NEEDS_MAP;
 755 }
 756
 757 static int
 758 i915_gem_execbuffer_reserve_vma(struct i915_vma *vma,
 759                                 struct intel_engine_cs *engine,
 760                                 bool *need_reloc)
 761 {
 762         struct drm_i915_gem_object *obj = vma->obj;
 763         struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
 764         uint64_t flags;
 765         int ret;
 766
 767         flags = PIN_USER;
 768         if (entry->flags & EXEC_OBJECT_NEEDS_GTT)
 769                 flags |= PIN_GLOBAL;
 770
 771         if (!drm_mm_node_allocated(&vma->node)) {
 772                 /* Wa32bitGeneralStateOffset & Wa32bitInstructionBaseOffset,
 773                  * limit address to the first 4GBs for unflagged objects.
 774                  */
 775                 if ((entry->flags & EXEC_OBJECT_SUPPORTS_48B_ADDRESS) == 0)
 776                         flags |= PIN_ZONE_4G;
 777                 if (entry->flags & __EXEC_OBJECT_NEEDS_MAP)
 778                         flags |= PIN_GLOBAL | PIN_MAPPABLE;
 779                 if (entry->flags & __EXEC_OBJECT_NEEDS_BIAS)
 780                         flags |= BATCH_OFFSET_BIAS | PIN_OFFSET_BIAS;
 781                 if (entry->flags & EXEC_OBJECT_PINNED)
 782                         flags |= entry->offset | PIN_OFFSET_FIXED;
 783                 if ((flags & PIN_MAPPABLE) == 0)
 784                         flags |= PIN_HIGH;
 785         }
 786
 787         ret = i915_vma_pin(vma,
 788                            entry->pad_to_size,
 789                            entry->alignment,
 790                            flags);
 791         if ((ret == -ENOSPC || ret == -E2BIG) &&
 792             only_mappable_for_reloc(entry->flags))
 793                 ret = i915_vma_pin(vma,
 794                                    entry->pad_to_size,
 795                                    entry->alignment,
 796                                    flags & ~PIN_MAPPABLE);
 797         if (ret)
 798                 return ret;
 799
 800         entry->flags |= __EXEC_OBJECT_HAS_PIN;
 801
 802         if (entry->flags & EXEC_OBJECT_NEEDS_FENCE) {
 803                 ret = i915_vma_get_fence(vma);
 804                 if (ret)
 805                         return ret;
 806
 807                 if (i915_vma_pin_fence(vma))
 808                         entry->flags |= __EXEC_OBJECT_HAS_FENCE;
 809         }
 810
 811         if (entry->offset != vma->node.start) {
 812                 entry->offset = vma->node.start;
 813                 *need_reloc = true;
 814         }
 815
 816         if (entry->flags & EXEC_OBJECT_WRITE) {
 817                 obj->base.pending_read_domains = I915_GEM_DOMAIN_RENDER;
 818                 obj->base.pending_write_domain = I915_GEM_DOMAIN_RENDER;
 819         }
 820
 821         return 0;
 822 }
 823
 824 static bool
 825 need_reloc_mappable(struct i915_vma *vma)
 826 {
 827         struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
 828
 829         if (entry->relocation_count == 0)
 830                 return false;
 831
 832         if (!i915_vma_is_ggtt(vma))
 833                 return false;
 834
 835         /* See also use_cpu_reloc() */
 836         if (HAS_LLC(to_i915(vma->obj->base.dev)))
 837                 return false;
 838
 839         if (vma->obj->base.write_domain == I915_GEM_DOMAIN_CPU)
 840                 return false;
 841
 842         return true;
 843 }
 844
 845 static bool
 846 eb_vma_misplaced(struct i915_vma *vma)
 847 {
 848         struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
 849
 850         WARN_ON(entry->flags & __EXEC_OBJECT_NEEDS_MAP &&
 851                 !i915_vma_is_ggtt(vma));
 852
 853         if (entry->alignment && !IS_ALIGNED(vma->node.start, entry->alignment))
 854                 return true;
 855
 856         if (vma->node.size < entry->pad_to_size)
 857                 return true;
 858
 859         if (entry->flags & EXEC_OBJECT_PINNED &&
 860             vma->node.start != entry->offset)
 861                 return true;
 862
 863         if (entry->flags & __EXEC_OBJECT_NEEDS_BIAS &&
 864             vma->node.start < BATCH_OFFSET_BIAS)
 865                 return true;
 866
 867         /* avoid costly ping-pong once a batch bo ended up non-mappable */
 868         if (entry->flags & __EXEC_OBJECT_NEEDS_MAP &&
 869             !i915_vma_is_map_and_fenceable(vma))
 870                 return !only_mappable_for_reloc(entry->flags);
 871
 872         if ((entry->flags & EXEC_OBJECT_SUPPORTS_48B_ADDRESS) == 0 &&
 873             (vma->node.start + vma->node.size - 1) >> 32)
 874                 return true;
 875
 876         return false;
 877 }
 878
 879 static int
 880 i915_gem_execbuffer_reserve(struct intel_engine_cs *engine,
 881                             struct list_head *vmas,
 882                             struct i915_gem_context *ctx,
 883                             bool *need_relocs)
 884 {
 885         struct drm_i915_gem_object *obj;
 886         struct i915_vma *vma;
 887         struct i915_address_space *vm;
 888         struct list_head ordered_vmas;
 889         struct list_head pinned_vmas;
 890         bool has_fenced_gpu_access = INTEL_GEN(engine->i915) < 4;
 891         bool needs_unfenced_map = INTEL_INFO(engine->i915)->unfenced_needs_alignment;
 892         int retry;
 893
 894         vm = list_first_entry(vmas, struct i915_vma, exec_list)->vm;
 895
 896         INIT_LIST_HEAD(&ordered_vmas);
 897         INIT_LIST_HEAD(&pinned_vmas);
 898         while (!list_empty(vmas)) {
 899                 struct drm_i915_gem_exec_object2 *entry;
 900                 bool need_fence, need_mappable;
 901
 902                 vma = list_first_entry(vmas, struct i915_vma, exec_list);
 903                 obj = vma->obj;
 904                 entry = vma->exec_entry;
 905
 906                 if (ctx->flags & CONTEXT_NO_ZEROMAP)
 907                         entry->flags |= __EXEC_OBJECT_NEEDS_BIAS;
 908
 909                 if (!has_fenced_gpu_access)
 910                         entry->flags &= ~EXEC_OBJECT_NEEDS_FENCE;
 911                 need_fence =
 912                         (entry->flags & EXEC_OBJECT_NEEDS_FENCE ||
 913                          needs_unfenced_map) &&
 914                         i915_gem_object_is_tiled(obj);
 915                 need_mappable = need_fence || need_reloc_mappable(vma);
 916
 917                 if (entry->flags & EXEC_OBJECT_PINNED)
 918                         list_move_tail(&vma->exec_list, &pinned_vmas);
 919                 else if (need_mappable) {
 920                         entry->flags |= __EXEC_OBJECT_NEEDS_MAP;
 921                         list_move(&vma->exec_list, &ordered_vmas);
 922                 } else
 923                         list_move_tail(&vma->exec_list, &ordered_vmas);
 924
 925                 obj->base.pending_read_domains = I915_GEM_GPU_DOMAINS & ~I915_GEM_DOMAIN_COMMAND;
 926                 obj->base.pending_write_domain = 0;
 927         }
 928         list_splice(&ordered_vmas, vmas);
 929         list_splice(&pinned_vmas, vmas);
 930
 931         /* Attempt to pin all of the buffers into the GTT.
 932          * This is done in 3 phases:
 933          *
 934          * 1a. Unbind all objects that do not match the GTT constraints for
 935          *     the execbuffer (fenceable, mappable, alignment etc).
 936          * 1b. Increment pin count for already bound objects.
 937          * 2.  Bind new objects.
 938          * 3.  Decrement pin count.
 939          *
 940          * This avoid unnecessary unbinding of later objects in order to make
 941          * room for the earlier objects *unless* we need to defragment.
 942          */
 943         retry = 0;
 944         do {
 945                 int ret = 0;
 946
 947                 /* Unbind any ill-fitting objects or pin. */
 948                 list_for_each_entry(vma, vmas, exec_list) {
 949                         if (!drm_mm_node_allocated(&vma->node))
 950                                 continue;
 951
 952                         if (eb_vma_misplaced(vma))
 953                                 ret = i915_vma_unbind(vma);
 954                         else
 955                                 ret = i915_gem_execbuffer_reserve_vma(vma,
 956                                                                       engine,
 957                                                                       need_relocs);
 958                         if (ret)
 959                                 goto err;
 960                 }
 961
 962                 /* Bind fresh objects */
 963                 list_for_each_entry(vma, vmas, exec_list) {
 964                         if (drm_mm_node_allocated(&vma->node))
 965                                 continue;
 966
 967                         ret = i915_gem_execbuffer_reserve_vma(vma, engine,
 968                                                               need_relocs);
 969                         if (ret)
 970                                 goto err;
 971                 }
 972
 973 err:
 974                 if (ret != -ENOSPC || retry++)
 975                         return ret;
 976
 977                 /* Decrement pin count for bound objects */
 978                 list_for_each_entry(vma, vmas, exec_list)
 979                         i915_gem_execbuffer_unreserve_vma(vma);
 980
 981                 ret = i915_gem_evict_vm(vm, true);
 982                 if (ret)
 983                         return ret;
 984         } while (1);
 985 }
 986
 987 static int
 988 i915_gem_execbuffer_relocate_slow(struct drm_device *dev,
 989                                   struct drm_i915_gem_execbuffer2 *args,
 990                                   struct drm_file *file,
 991                                   struct intel_engine_cs *engine,
 992                                   struct eb_vmas *eb,
 993                                   struct drm_i915_gem_exec_object2 *exec,
 994                                   struct i915_gem_context *ctx)
 995 {
 996         struct drm_i915_gem_relocation_entry *reloc;
 997         struct i915_address_space *vm;
 998         struct i915_vma *vma;
 999         bool need_relocs;
1000         int *reloc_offset;
1001         int i, total, ret;
1002         unsigned count = args->buffer_count;
1003
1004         vm = list_first_entry(&eb->vmas, struct i915_vma, exec_list)->vm;
1005
1006         /* We may process another execbuffer during the unlock... */
1007         while (!list_empty(&eb->vmas)) {
1008                 vma = list_first_entry(&eb->vmas, struct i915_vma, exec_list);
1009                 list_del_init(&vma->exec_list);
1010                 i915_gem_execbuffer_unreserve_vma(vma);
1011                 i915_vma_put(vma);
1012         }
1013
1014         mutex_unlock(&dev->struct_mutex);
1015
1016         total = 0;
1017         for (i = 0; i < count; i++)
1018                 total += exec[i].relocation_count;
1019
1020         reloc_offset = drm_malloc_ab(count, sizeof(*reloc_offset));
1021         reloc = drm_malloc_ab(total, sizeof(*reloc));
1022         if (reloc == NULL || reloc_offset == NULL) {
1023                 drm_free_large(reloc);
1024                 drm_free_large(reloc_offset);
1025                 mutex_lock(&dev->struct_mutex);
1026                 return -ENOMEM;
1027         }
1028
1029         total = 0;
1030         for (i = 0; i < count; i++) {
1031                 struct drm_i915_gem_relocation_entry __user *user_relocs;
1032                 u64 invalid_offset = (u64)-1;
1033                 int j;
1034
1035                 user_relocs = u64_to_user_ptr(exec[i].relocs_ptr);
1036
1037                 if (copy_from_user(reloc+total, user_relocs,
1038                                    exec[i].relocation_count * sizeof(*reloc))) {
1039                         ret = -EFAULT;
1040                         mutex_lock(&dev->struct_mutex);
1041                         goto err;
1042                 }
1043
1044                 /* As we do not update the known relocation offsets after
1045                  * relocating (due to the complexities in lock handling),
1046                  * we need to mark them as invalid now so that we force the
1047                  * relocation processing next time. Just in case the target
1048                  * object is evicted and then rebound into its old
1049                  * presumed_offset before the next execbuffer - if that
1050                  * happened we would make the mistake of assuming that the
1051                  * relocations were valid.
1052                  */
1053                 for (j = 0; j < exec[i].relocation_count; j++) {
1054                         if (__copy_to_user(&user_relocs[j].presumed_offset,
1055                                            &invalid_offset,
1056                                            sizeof(invalid_offset))) {
1057                                 ret = -EFAULT;
1058                                 mutex_lock(&dev->struct_mutex);
1059                                 goto err;
1060                         }
1061                 }
1062
1063                 reloc_offset[i] = total;
1064                 total += exec[i].relocation_count;
1065         }
1066
1067         ret = i915_mutex_lock_interruptible(dev);
1068         if (ret) {
1069                 mutex_lock(&dev->struct_mutex);
1070                 goto err;
1071         }
1072
1073         /* reacquire the objects */
1074         eb_reset(eb);
1075         ret = eb_lookup_vmas(eb, exec, args, vm, file);
1076         if (ret)
1077                 goto err;
1078
1079         need_relocs = (args->flags & I915_EXEC_NO_RELOC) == 0;
1080         ret = i915_gem_execbuffer_reserve(engine, &eb->vmas, ctx,
1081                                           &need_relocs);
1082         if (ret)
1083                 goto err;
1084
1085         list_for_each_entry(vma, &eb->vmas, exec_list) {
1086                 int offset = vma->exec_entry - exec;
1087                 ret = i915_gem_execbuffer_relocate_vma_slow(vma, eb,
1088                                                             reloc + reloc_offset[offset]);
1089                 if (ret)
1090                         goto err;
1091         }
1092
1093         /* Leave the user relocations as are, this is the painfully slow path,
1094          * and we want to avoid the complication of dropping the lock whilst
1095          * having buffers reserved in the aperture and so causing spurious
1096          * ENOSPC for random operations.
1097          */
1098
1099 err:
1100         drm_free_large(reloc);
1101         drm_free_large(reloc_offset);
1102         return ret;
1103 }
1104
1105 static int
1106 i915_gem_execbuffer_move_to_gpu(struct drm_i915_gem_request *req,
1107                                 struct list_head *vmas)
1108 {
1109         struct i915_vma *vma;
1110         int ret;
1111
1112         list_for_each_entry(vma, vmas, exec_list) {
1113                 struct drm_i915_gem_object *obj = vma->obj;
1114
1115                 ret = i915_gem_request_await_object
1116                         (req, obj, obj->base.pending_write_domain);
1117                 if (ret)
1118                         return ret;
1119
1120                 if (obj->base.write_domain & I915_GEM_DOMAIN_CPU)
1121                         i915_gem_clflush_object(obj, false);
1122         }
1123
1124         /* Unconditionally flush any chipset caches (for streaming writes). */
1125         i915_gem_chipset_flush(req->engine->i915);
1126
1127         /* Unconditionally invalidate GPU caches and TLBs. */
1128         return req->engine->emit_flush(req, EMIT_INVALIDATE);
1129 }
1130
1131 static bool
1132 i915_gem_check_execbuffer(struct drm_i915_gem_execbuffer2 *exec)
1133 {
1134         if (exec->flags & __I915_EXEC_UNKNOWN_FLAGS)
1135                 return false;
1136
1137         /* Kernel clipping was a DRI1 misfeature */
1138         if (exec->num_cliprects || exec->cliprects_ptr)
1139                 return false;
1140
1141         if (exec->DR4 == 0xffffffff) {
1142                 DRM_DEBUG("UXA submitting garbage DR4, fixing up\n");
1143                 exec->DR4 = 0;
1144         }
1145         if (exec->DR1 || exec->DR4)
1146                 return false;
1147
1148         if ((exec->batch_start_offset | exec->batch_len) & 0x7)
1149                 return false;
1150
1151         return true;
1152 }
1153
1154 static int
1155 validate_exec_list(struct drm_device *dev,
1156                    struct drm_i915_gem_exec_object2 *exec,
1157                    int count)
1158 {
1159         unsigned relocs_total = 0;
1160         unsigned relocs_max = UINT_MAX / sizeof(struct drm_i915_gem_relocation_entry);
1161         unsigned invalid_flags;
1162         int i;
1163
1164         /* INTERNAL flags must not overlap with external ones */
1165         BUILD_BUG_ON(__EXEC_OBJECT_INTERNAL_FLAGS & ~__EXEC_OBJECT_UNKNOWN_FLAGS);
1166
1167         invalid_flags = __EXEC_OBJECT_UNKNOWN_FLAGS;
1168         if (USES_FULL_PPGTT(dev))
1169                 invalid_flags |= EXEC_OBJECT_NEEDS_GTT;
1170
1171         for (i = 0; i < count; i++) {
1172                 char __user *ptr = u64_to_user_ptr(exec[i].relocs_ptr);
1173                 int length; /* limited by fault_in_pages_readable() */
1174
1175                 if (exec[i].flags & invalid_flags)
1176                         return -EINVAL;
1177
1178                 /* Offset can be used as input (EXEC_OBJECT_PINNED), reject
1179                  * any non-page-aligned or non-canonical addresses.
1180                  */
1181                 if (exec[i].flags & EXEC_OBJECT_PINNED) {
1182                         if (exec[i].offset !=
1183                             gen8_canonical_addr(exec[i].offset & PAGE_MASK))
1184                                 return -EINVAL;
1185                 }
1186
1187                 /* From drm_mm perspective address space is continuous,
1188                  * so from this point we're always using non-canonical
1189                  * form internally.
1190                  */
1191                 exec[i].offset = gen8_noncanonical_addr(exec[i].offset);
1192
1193                 if (exec[i].alignment && !is_power_of_2(exec[i].alignment))
1194                         return -EINVAL;
1195
1196                 /* pad_to_size was once a reserved field, so sanitize it */
1197                 if (exec[i].flags & EXEC_OBJECT_PAD_TO_SIZE) {
1198                         if (offset_in_page(exec[i].pad_to_size))
1199                                 return -EINVAL;
1200                 } else {
1201                         exec[i].pad_to_size = 0;
1202                 }
1203
1204                 /* First check for malicious input causing overflow in
1205                  * the worst case where we need to allocate the entire
1206                  * relocation tree as a single array.
1207                  */
1208                 if (exec[i].relocation_count > relocs_max - relocs_total)
1209                         return -EINVAL;
1210                 relocs_total += exec[i].relocation_count;
1211
1212                 length = exec[i].relocation_count *
1213                         sizeof(struct drm_i915_gem_relocation_entry);
1214                 /*
1215                  * We must check that the entire relocation array is safe
1216                  * to read, but since we may need to update the presumed
1217                  * offsets during execution, check for full write access.
1218                  */
1219                 if (!access_ok(VERIFY_WRITE, ptr, length))
1220                         return -EFAULT;
1221
1222                 if (likely(!i915.prefault_disable)) {
1223                         if (fault_in_pages_readable(ptr, length))
1224                                 return -EFAULT;
1225                 }
1226         }
1227
1228         return 0;
1229 }
1230
1231 static struct i915_gem_context *
1232 i915_gem_validate_context(struct drm_device *dev, struct drm_file *file,
1233                           struct intel_engine_cs *engine, const u32 ctx_id)
1234 {
1235         struct i915_gem_context *ctx;
1236
1237         ctx = i915_gem_context_lookup(file->driver_priv, ctx_id);
1238         if (IS_ERR(ctx))
1239                 return ctx;
1240
1241         if (i915_gem_context_is_banned(ctx)) {
1242                 DRM_DEBUG("Context %u tried to submit while banned\n", ctx_id);
1243                 return ERR_PTR(-EIO);
1244         }
1245
1246         return ctx;
1247 }
1248
1249 static bool gpu_write_needs_clflush(struct drm_i915_gem_object *obj)
1250 {
1251         return !(obj->cache_level == I915_CACHE_NONE ||
1252                  obj->cache_level == I915_CACHE_WT);
1253 }
1254
1255 void i915_vma_move_to_active(struct i915_vma *vma,
1256                              struct drm_i915_gem_request *req,
1257                              unsigned int flags)
1258 {
1259         struct drm_i915_gem_object *obj = vma->obj;
1260         const unsigned int idx = req->engine->id;
1261
1262         lockdep_assert_held(&req->i915->drm.struct_mutex);
1263         GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
1264
1265         /* Add a reference if we're newly entering the active list.
1266          * The order in which we add operations to the retirement queue is
1267          * vital here: mark_active adds to the start of the callback list,
1268          * such that subsequent callbacks are called first. Therefore we
1269          * add the active reference first and queue for it to be dropped
1270          * *last*.
1271          */
1272         if (!i915_vma_is_active(vma))
1273                 obj->active_count++;
1274         i915_vma_set_active(vma, idx);
1275         i915_gem_active_set(&vma->last_read[idx], req);
1276         list_move_tail(&vma->vm_link, &vma->vm->active_list);
1277
1278         if (flags & EXEC_OBJECT_WRITE) {
1279                 if (intel_fb_obj_invalidate(obj, ORIGIN_CS))
1280                         i915_gem_active_set(&obj->frontbuffer_write, req);
1281
1282                 /* update for the implicit flush after a batch */
1283                 obj->base.write_domain &= ~I915_GEM_GPU_DOMAINS;
1284                 if (!obj->cache_dirty && gpu_write_needs_clflush(obj))
1285                         obj->cache_dirty = true;
1286         }
1287
1288         if (flags & EXEC_OBJECT_NEEDS_FENCE)
1289                 i915_gem_active_set(&vma->last_fence, req);
1290 }
1291
1292 static void eb_export_fence(struct drm_i915_gem_object *obj,
1293                             struct drm_i915_gem_request *req,
1294                             unsigned int flags)
1295 {
1296         struct reservation_object *resv = obj->resv;
1297
1298         /* Ignore errors from failing to allocate the new fence, we can't
1299          * handle an error right now. Worst case should be missed
1300          * synchronisation leading to rendering corruption.
1301          */
1302         ww_mutex_lock(&resv->lock, NULL);
1303         if (flags & EXEC_OBJECT_WRITE)
1304                 reservation_object_add_excl_fence(resv, &req->fence);
1305         else if (reservation_object_reserve_shared(resv) == 0)
1306                 reservation_object_add_shared_fence(resv, &req->fence);
1307         ww_mutex_unlock(&resv->lock);
1308 }
1309
1310 static void
1311 i915_gem_execbuffer_move_to_active(struct list_head *vmas,
1312                                    struct drm_i915_gem_request *req)
1313 {
1314         struct i915_vma *vma;
1315
1316         list_for_each_entry(vma, vmas, exec_list) {
1317                 struct drm_i915_gem_object *obj = vma->obj;
1318                 u32 old_read = obj->base.read_domains;
1319                 u32 old_write = obj->base.write_domain;
1320
1321                 obj->base.write_domain = obj->base.pending_write_domain;
1322                 if (obj->base.write_domain)
1323                         vma->exec_entry->flags |= EXEC_OBJECT_WRITE;
1324                 else
1325                         obj->base.pending_read_domains |= obj->base.read_domains;
1326                 obj->base.read_domains = obj->base.pending_read_domains;
1327
1328                 i915_vma_move_to_active(vma, req, vma->exec_entry->flags);
1329                 eb_export_fence(obj, req, vma->exec_entry->flags);
1330                 trace_i915_gem_object_change_domain(obj, old_read, old_write);
1331         }
1332 }
1333
1334 static int
1335 i915_reset_gen7_sol_offsets(struct drm_i915_gem_request *req)
1336 {
1337         struct intel_ring *ring = req->ring;
1338         int ret, i;
1339
1340         if (!IS_GEN7(req->i915) || req->engine->id != RCS) {
1341                 DRM_DEBUG("sol reset is gen7/rcs only\n");
1342                 return -EINVAL;
1343         }
1344
1345         ret = intel_ring_begin(req, 4 * 3);
1346         if (ret)
1347                 return ret;
1348
1349         for (i = 0; i < 4; i++) {
1350                 intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
1351                 intel_ring_emit_reg(ring, GEN7_SO_WRITE_OFFSET(i));
1352                 intel_ring_emit(ring, 0);
1353         }
1354
1355         intel_ring_advance(ring);
1356
1357         return 0;
1358 }
1359
1360 static struct i915_vma *
1361 i915_gem_execbuffer_parse(struct intel_engine_cs *engine,
1362                           struct drm_i915_gem_exec_object2 *shadow_exec_entry,
1363                           struct drm_i915_gem_object *batch_obj,
1364                           struct eb_vmas *eb,
1365                           u32 batch_start_offset,
1366                           u32 batch_len,
1367                           bool is_master)
1368 {
1369         struct drm_i915_gem_object *shadow_batch_obj;
1370         struct i915_vma *vma;
1371         int ret;
1372
1373         shadow_batch_obj = i915_gem_batch_pool_get(&engine->batch_pool,
1374                                                    PAGE_ALIGN(batch_len));
1375         if (IS_ERR(shadow_batch_obj))
1376                 return ERR_CAST(shadow_batch_obj);
1377
1378         ret = intel_engine_cmd_parser(engine,
1379                                       batch_obj,
1380                                       shadow_batch_obj,
1381                                       batch_start_offset,
1382                                       batch_len,
1383                                       is_master);
1384         if (ret) {
1385                 if (ret == -EACCES) /* unhandled chained batch */
1386                         vma = NULL;
1387                 else
1388                         vma = ERR_PTR(ret);
1389                 goto out;
1390         }
1391
1392         vma = i915_gem_object_ggtt_pin(shadow_batch_obj, NULL, 0, 0, 0);
1393         if (IS_ERR(vma))
1394                 goto out;
1395
1396         memset(shadow_exec_entry, 0, sizeof(*shadow_exec_entry));
1397
1398         vma->exec_entry = shadow_exec_entry;
1399         vma->exec_entry->flags = __EXEC_OBJECT_HAS_PIN;
1400         i915_gem_object_get(shadow_batch_obj);
1401         list_add_tail(&vma->exec_list, &eb->vmas);
1402
1403 out:
1404         i915_gem_object_unpin_pages(shadow_batch_obj);
1405         return vma;
1406 }
1407
1408 static int
1409 execbuf_submit(struct i915_execbuffer_params *params,
1410                struct drm_i915_gem_execbuffer2 *args,
1411                struct list_head *vmas)
1412 {
1413         u64 exec_start, exec_len;
1414         int ret;
1415
1416         ret = i915_gem_execbuffer_move_to_gpu(params->request, vmas);
1417         if (ret)
1418                 return ret;
1419
1420         ret = i915_switch_context(params->request);
1421         if (ret)
1422                 return ret;
1423
1424         if (args->flags & I915_EXEC_CONSTANTS_MASK) {
1425                 DRM_DEBUG("I915_EXEC_CONSTANTS_* unsupported\n");
1426                 return -EINVAL;
1427         }
1428
1429         if (args->flags & I915_EXEC_GEN7_SOL_RESET) {
1430                 ret = i915_reset_gen7_sol_offsets(params->request);
1431                 if (ret)
1432                         return ret;
1433         }
1434
1435         exec_len   = args->batch_len;
1436         exec_start = params->batch->node.start +
1437                      params->args_batch_start_offset;
1438
1439         if (exec_len == 0)
1440                 exec_len = params->batch->size - params->args_batch_start_offset;
1441
1442         ret = params->engine->emit_bb_start(params->request,
1443                                             exec_start, exec_len,
1444                                             params->dispatch_flags);
1445         if (ret)
1446                 return ret;
1447
1448         trace_i915_gem_ring_dispatch(params->request, params->dispatch_flags);
1449
1450         i915_gem_execbuffer_move_to_active(vmas, params->request);
1451
1452         return 0;
1453 }
1454
1455 /**
1456  * Find one BSD ring to dispatch the corresponding BSD command.
1457  * The engine index is returned.
1458  */
1459 static unsigned int
1460 gen8_dispatch_bsd_engine(struct drm_i915_private *dev_priv,
1461                          struct drm_file *file)
1462 {
1463         struct drm_i915_file_private *file_priv = file->driver_priv;
1464
1465         /* Check whether the file_priv has already selected one ring. */
1466         if ((int)file_priv->bsd_engine < 0)
1467                 file_priv->bsd_engine = atomic_fetch_xor(1,
1468                          &dev_priv->mm.bsd_engine_dispatch_index);
1469
1470         return file_priv->bsd_engine;
1471 }
1472
1473 #define I915_USER_RINGS (4)
1474
1475 static const enum intel_engine_id user_ring_map[I915_USER_RINGS + 1] = {
1476         [I915_EXEC_DEFAULT]     = RCS,
1477         [I915_EXEC_RENDER]      = RCS,
1478         [I915_EXEC_BLT]         = BCS,
1479         [I915_EXEC_BSD]         = VCS,
1480         [I915_EXEC_VEBOX]       = VECS
1481 };
1482
1483 static struct intel_engine_cs *
1484 eb_select_engine(struct drm_i915_private *dev_priv,
1485                  struct drm_file *file,
1486                  struct drm_i915_gem_execbuffer2 *args)
1487 {
1488         unsigned int user_ring_id = args->flags & I915_EXEC_RING_MASK;
1489         struct intel_engine_cs *engine;
1490
1491         if (user_ring_id > I915_USER_RINGS) {
1492                 DRM_DEBUG("execbuf with unknown ring: %u\n", user_ring_id);
1493                 return NULL;
1494         }
1495
1496         if ((user_ring_id != I915_EXEC_BSD) &&
1497             ((args->flags & I915_EXEC_BSD_MASK) != 0)) {
1498                 DRM_DEBUG("execbuf with non bsd ring but with invalid "
1499                           "bsd dispatch flags: %d\n", (int)(args->flags));
1500                 return NULL;
1501         }
1502
1503         if (user_ring_id == I915_EXEC_BSD && HAS_BSD2(dev_priv)) {
1504                 unsigned int bsd_idx = args->flags & I915_EXEC_BSD_MASK;
1505
1506                 if (bsd_idx == I915_EXEC_BSD_DEFAULT) {
1507                         bsd_idx = gen8_dispatch_bsd_engine(dev_priv, file);
1508                 } else if (bsd_idx >= I915_EXEC_BSD_RING1 &&
1509                            bsd_idx <= I915_EXEC_BSD_RING2) {
1510                         bsd_idx >>= I915_EXEC_BSD_SHIFT;
1511                         bsd_idx--;
1512                 } else {
1513                         DRM_DEBUG("execbuf with unknown bsd ring: %u\n",
1514                                   bsd_idx);
1515                         return NULL;
1516                 }
1517
1518                 engine = dev_priv->engine[_VCS(bsd_idx)];
1519         } else {
1520                 engine = dev_priv->engine[user_ring_map[user_ring_id]];
1521         }
1522
1523         if (!engine) {
1524                 DRM_DEBUG("execbuf with invalid ring: %u\n", user_ring_id);
1525                 return NULL;
1526         }
1527
1528         return engine;
1529 }
1530
1531 static int
1532 i915_gem_do_execbuffer(struct drm_device *dev, void *data,
1533                        struct drm_file *file,
1534                        struct drm_i915_gem_execbuffer2 *args,
1535                        struct drm_i915_gem_exec_object2 *exec)
1536 {
1537         struct drm_i915_private *dev_priv = to_i915(dev);
1538         struct i915_ggtt *ggtt = &dev_priv->ggtt;
1539         struct eb_vmas *eb;
1540         struct drm_i915_gem_exec_object2 shadow_exec_entry;
1541         struct intel_engine_cs *engine;
1542         struct i915_gem_context *ctx;
1543         struct i915_address_space *vm;
1544         struct i915_execbuffer_params params_master; /* XXX: will be removed later */
1545         struct i915_execbuffer_params *params = &params_master;
1546         const u32 ctx_id = i915_execbuffer2_get_context_id(*args);
1547         u32 dispatch_flags;
1548         int ret;
1549         bool need_relocs;
1550
1551         if (!i915_gem_check_execbuffer(args))
1552                 return -EINVAL;
1553
1554         ret = validate_exec_list(dev, exec, args->buffer_count);
1555         if (ret)
1556                 return ret;
1557
1558         dispatch_flags = 0;
1559         if (args->flags & I915_EXEC_SECURE) {
1560                 if (!drm_is_current_master(file) || !capable(CAP_SYS_ADMIN))
1561                     return -EPERM;
1562
1563                 dispatch_flags |= I915_DISPATCH_SECURE;
1564         }
1565         if (args->flags & I915_EXEC_IS_PINNED)
1566                 dispatch_flags |= I915_DISPATCH_PINNED;
1567
1568         engine = eb_select_engine(dev_priv, file, args);
1569         if (!engine)
1570                 return -EINVAL;
1571
1572         if (args->buffer_count < 1) {
1573                 DRM_DEBUG("execbuf with %d buffers\n", args->buffer_count);
1574                 return -EINVAL;
1575         }
1576
1577         if (args->flags & I915_EXEC_RESOURCE_STREAMER) {
1578                 if (!HAS_RESOURCE_STREAMER(dev_priv)) {
1579                         DRM_DEBUG("RS is only allowed for Haswell, Gen8 and above\n");
1580                         return -EINVAL;
1581                 }
1582                 if (engine->id != RCS) {
1583                         DRM_DEBUG("RS is not available on %s\n",
1584                                  engine->name);
1585                         return -EINVAL;
1586                 }
1587
1588                 dispatch_flags |= I915_DISPATCH_RS;
1589         }
1590
1591         /* Take a local wakeref for preparing to dispatch the execbuf as
1592          * we expect to access the hardware fairly frequently in the
1593          * process. Upon first dispatch, we acquire another prolonged
1594          * wakeref that we hold until the GPU has been idle for at least
1595          * 100ms.
1596          */
1597         intel_runtime_pm_get(dev_priv);
1598
1599         ret = i915_mutex_lock_interruptible(dev);
1600         if (ret)
1601                 goto pre_mutex_err;
1602
1603         ctx = i915_gem_validate_context(dev, file, engine, ctx_id);
1604         if (IS_ERR(ctx)) {
1605                 mutex_unlock(&dev->struct_mutex);
1606                 ret = PTR_ERR(ctx);
1607                 goto pre_mutex_err;
1608         }
1609
1610         i915_gem_context_get(ctx);
1611
1612         if (ctx->ppgtt)
1613                 vm = &ctx->ppgtt->base;
1614         else
1615                 vm = &ggtt->base;
1616
1617         memset(&params_master, 0x00, sizeof(params_master));
1618
1619         eb = eb_create(dev_priv, args);
1620         if (eb == NULL) {
1621                 i915_gem_context_put(ctx);
1622                 mutex_unlock(&dev->struct_mutex);
1623                 ret = -ENOMEM;
1624                 goto pre_mutex_err;
1625         }
1626
1627         /* Look up object handles */
1628         ret = eb_lookup_vmas(eb, exec, args, vm, file);
1629         if (ret)
1630                 goto err;
1631
1632         /* take note of the batch buffer before we might reorder the lists */
1633         params->batch = eb_get_batch(eb);
1634
1635         /* Move the objects en-masse into the GTT, evicting if necessary. */
1636         need_relocs = (args->flags & I915_EXEC_NO_RELOC) == 0;
1637         ret = i915_gem_execbuffer_reserve(engine, &eb->vmas, ctx,
1638                                           &need_relocs);
1639         if (ret)
1640                 goto err;
1641
1642         /* The objects are in their final locations, apply the relocations. */
1643         if (need_relocs)
1644                 ret = i915_gem_execbuffer_relocate(eb);
1645         if (ret) {
1646                 if (ret == -EFAULT) {
1647                         ret = i915_gem_execbuffer_relocate_slow(dev, args, file,
1648                                                                 engine,
1649                                                                 eb, exec, ctx);
1650                         BUG_ON(!mutex_is_locked(&dev->struct_mutex));
1651                 }
1652                 if (ret)
1653                         goto err;
1654         }
1655
1656         /* Set the pending read domains for the batch buffer to COMMAND */
1657         if (params->batch->obj->base.pending_write_domain) {
1658                 DRM_DEBUG("Attempting to use self-modifying batch buffer\n");
1659                 ret = -EINVAL;
1660                 goto err;
1661         }
1662         if (args->batch_start_offset > params->batch->size ||
1663             args->batch_len > params->batch->size - args->batch_start_offset) {
1664                 DRM_DEBUG("Attempting to use out-of-bounds batch\n");
1665                 ret = -EINVAL;
1666                 goto err;
1667         }
1668
1669         params->args_batch_start_offset = args->batch_start_offset;
1670         if (engine->needs_cmd_parser && args->batch_len) {
1671                 struct i915_vma *vma;
1672
1673                 vma = i915_gem_execbuffer_parse(engine, &shadow_exec_entry,
1674                                                 params->batch->obj,
1675                                                 eb,
1676                                                 args->batch_start_offset,
1677                                                 args->batch_len,
1678                                                 drm_is_current_master(file));
1679                 if (IS_ERR(vma)) {
1680                         ret = PTR_ERR(vma);
1681                         goto err;
1682                 }
1683
1684                 if (vma) {
1685                         /*
1686                          * Batch parsed and accepted:
1687                          *
1688                          * Set the DISPATCH_SECURE bit to remove the NON_SECURE
1689                          * bit from MI_BATCH_BUFFER_START commands issued in
1690                          * the dispatch_execbuffer implementations. We
1691                          * specifically don't want that set on batches the
1692                          * command parser has accepted.
1693                          */
1694                         dispatch_flags |= I915_DISPATCH_SECURE;
1695                         params->args_batch_start_offset = 0;
1696                         params->batch = vma;
1697                 }
1698         }
1699
1700         params->batch->obj->base.pending_read_domains |= I915_GEM_DOMAIN_COMMAND;
1701
1702         /* snb/ivb/vlv conflate the "batch in ppgtt" bit with the "non-secure
1703          * batch" bit. Hence we need to pin secure batches into the global gtt.
1704          * hsw should have this fixed, but bdw mucks it up again. */
1705         if (dispatch_flags & I915_DISPATCH_SECURE) {
1706                 struct drm_i915_gem_object *obj = params->batch->obj;
1707                 struct i915_vma *vma;
1708
1709                 /*
1710                  * So on first glance it looks freaky that we pin the batch here
1711                  * outside of the reservation loop. But:
1712                  * - The batch is already pinned into the relevant ppgtt, so we
1713                  *   already have the backing storage fully allocated.
1714                  * - No other BO uses the global gtt (well contexts, but meh),
1715                  *   so we don't really have issues with multiple objects not
1716                  *   fitting due to fragmentation.
1717                  * So this is actually safe.
1718                  */
1719                 vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
1720                 if (IS_ERR(vma)) {
1721                         ret = PTR_ERR(vma);
1722                         goto err;
1723                 }
1724
1725                 params->batch = vma;
1726         }
1727
1728         /* Allocate a request for this batch buffer nice and early. */
1729         params->request = i915_gem_request_alloc(engine, ctx);
1730         if (IS_ERR(params->request)) {
1731                 ret = PTR_ERR(params->request);
1732                 goto err_batch_unpin;
1733         }
1734
1735         /* Whilst this request exists, batch_obj will be on the
1736          * active_list, and so will hold the active reference. Only when this
1737          * request is retired will the the batch_obj be moved onto the
1738          * inactive_list and lose its active reference. Hence we do not need
1739          * to explicitly hold another reference here.
1740          */
1741         params->request->batch = params->batch;
1742
1743         ret = i915_gem_request_add_to_client(params->request, file);
1744         if (ret)
1745                 goto err_request;
1746
1747         /*
1748          * Save assorted stuff away to pass through to *_submission().
1749          * NB: This data should be 'persistent' and not local as it will
1750          * kept around beyond the duration of the IOCTL once the GPU
1751          * scheduler arrives.
1752          */
1753         params->dev                     = dev;
1754         params->file                    = file;
1755         params->engine                    = engine;
1756         params->dispatch_flags          = dispatch_flags;
1757         params->ctx                     = ctx;
1758
1759         ret = execbuf_submit(params, args, &eb->vmas);
1760 err_request:
1761         __i915_add_request(params->request, ret == 0);
1762
1763 err_batch_unpin:
1764         /*
1765          * FIXME: We crucially rely upon the active tracking for the (ppgtt)
1766          * batch vma for correctness. For less ugly and less fragility this
1767          * needs to be adjusted to also track the ggtt batch vma properly as
1768          * active.
1769          */
1770         if (dispatch_flags & I915_DISPATCH_SECURE)
1771                 i915_vma_unpin(params->batch);
1772 err:
1773         /* the request owns the ref now */
1774         i915_gem_context_put(ctx);
1775         eb_destroy(eb);
1776
1777         mutex_unlock(&dev->struct_mutex);
1778
1779 pre_mutex_err:
1780         /* intel_gpu_busy should also get a ref, so it will free when the device
1781          * is really idle. */
1782         intel_runtime_pm_put(dev_priv);
1783         return ret;
1784 }
1785
1786 /*
1787  * Legacy execbuffer just creates an exec2 list from the original exec object
1788  * list array and passes it to the real function.
1789  */
1790 int
1791 i915_gem_execbuffer(struct drm_device *dev, void *data,
1792                     struct drm_file *file)
1793 {
1794         struct drm_i915_gem_execbuffer *args = data;
1795         struct drm_i915_gem_execbuffer2 exec2;
1796         struct drm_i915_gem_exec_object *exec_list = NULL;
1797         struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1798         int ret, i;
1799
1800         if (args->buffer_count < 1) {
1801                 DRM_DEBUG("execbuf with %d buffers\n", args->buffer_count);
1802                 return -EINVAL;
1803         }
1804
1805         /* Copy in the exec list from userland */
1806         exec_list = drm_malloc_ab(sizeof(*exec_list), args->buffer_count);
1807         exec2_list = drm_malloc_ab(sizeof(*exec2_list), args->buffer_count);
1808         if (exec_list == NULL || exec2_list == NULL) {
1809                 DRM_DEBUG("Failed to allocate exec list for %d buffers\n",
1810                           args->buffer_count);
1811                 drm_free_large(exec_list);
1812                 drm_free_large(exec2_list);
1813                 return -ENOMEM;
1814         }
1815         ret = copy_from_user(exec_list,
1816                              u64_to_user_ptr(args->buffers_ptr),
1817                              sizeof(*exec_list) * args->buffer_count);
1818         if (ret != 0) {
1819                 DRM_DEBUG("copy %d exec entries failed %d\n",
1820                           args->buffer_count, ret);
1821                 drm_free_large(exec_list);
1822                 drm_free_large(exec2_list);
1823                 return -EFAULT;
1824         }
1825
1826         for (i = 0; i < args->buffer_count; i++) {
1827                 exec2_list[i].handle = exec_list[i].handle;
1828                 exec2_list[i].relocation_count = exec_list[i].relocation_count;
1829                 exec2_list[i].relocs_ptr = exec_list[i].relocs_ptr;
1830                 exec2_list[i].alignment = exec_list[i].alignment;
1831                 exec2_list[i].offset = exec_list[i].offset;
1832                 if (INTEL_GEN(to_i915(dev)) < 4)
1833                         exec2_list[i].flags = EXEC_OBJECT_NEEDS_FENCE;
1834                 else
1835                         exec2_list[i].flags = 0;
1836         }
1837
1838         exec2.buffers_ptr = args->buffers_ptr;
1839         exec2.buffer_count = args->buffer_count;
1840         exec2.batch_start_offset = args->batch_start_offset;
1841         exec2.batch_len = args->batch_len;
1842         exec2.DR1 = args->DR1;
1843         exec2.DR4 = args->DR4;
1844         exec2.num_cliprects = args->num_cliprects;
1845         exec2.cliprects_ptr = args->cliprects_ptr;
1846         exec2.flags = I915_EXEC_RENDER;
1847         i915_execbuffer2_set_context_id(exec2, 0);
1848
1849         ret = i915_gem_do_execbuffer(dev, data, file, &exec2, exec2_list);
1850         if (!ret) {
1851                 struct drm_i915_gem_exec_object __user *user_exec_list =
1852                         u64_to_user_ptr(args->buffers_ptr);
1853
1854                 /* Copy the new buffer offsets back to the user's exec list. */
1855                 for (i = 0; i < args->buffer_count; i++) {
1856                         exec2_list[i].offset =
1857                                 gen8_canonical_addr(exec2_list[i].offset);
1858                         ret = __copy_to_user(&user_exec_list[i].offset,
1859                                              &exec2_list[i].offset,
1860                                              sizeof(user_exec_list[i].offset));
1861                         if (ret) {
1862                                 ret = -EFAULT;
1863                                 DRM_DEBUG("failed to copy %d exec entries "
1864                                           "back to user (%d)\n",
1865                                           args->buffer_count, ret);
1866                                 break;
1867                         }
1868                 }
1869         }
1870
1871         drm_free_large(exec_list);
1872         drm_free_large(exec2_list);
1873         return ret;
1874 }
1875
1876 int
1877 i915_gem_execbuffer2(struct drm_device *dev, void *data,
1878                      struct drm_file *file)
1879 {
1880         struct drm_i915_gem_execbuffer2 *args = data;
1881         struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1882         int ret;
1883
1884         if (args->buffer_count < 1 ||
1885             args->buffer_count > UINT_MAX / sizeof(*exec2_list)) {
1886                 DRM_DEBUG("execbuf2 with %d buffers\n", args->buffer_count);
1887                 return -EINVAL;
1888         }
1889
1890         if (args->rsvd2 != 0) {
1891                 DRM_DEBUG("dirty rvsd2 field\n");
1892                 return -EINVAL;
1893         }
1894
1895         exec2_list = drm_malloc_gfp(args->buffer_count,
1896                                     sizeof(*exec2_list),
1897                                     GFP_TEMPORARY);
1898         if (exec2_list == NULL) {
1899                 DRM_DEBUG("Failed to allocate exec list for %d buffers\n",
1900                           args->buffer_count);
1901                 return -ENOMEM;
1902         }
1903         ret = copy_from_user(exec2_list,
1904                              u64_to_user_ptr(args->buffers_ptr),
1905                              sizeof(*exec2_list) * args->buffer_count);
1906         if (ret != 0) {
1907                 DRM_DEBUG("copy %d exec entries failed %d\n",
1908                           args->buffer_count, ret);
1909                 drm_free_large(exec2_list);
1910                 return -EFAULT;
1911         }
1912
1913         ret = i915_gem_do_execbuffer(dev, data, file, args, exec2_list);
1914         if (!ret) {
1915                 /* Copy the new buffer offsets back to the user's exec list. */
1916                 struct drm_i915_gem_exec_object2 __user *user_exec_list =
1917                                    u64_to_user_ptr(args->buffers_ptr);
1918                 int i;
1919
1920                 for (i = 0; i < args->buffer_count; i++) {
1921                         exec2_list[i].offset =
1922                                 gen8_canonical_addr(exec2_list[i].offset);
1923                         ret = __copy_to_user(&user_exec_list[i].offset,
1924                                              &exec2_list[i].offset,
1925                                              sizeof(user_exec_list[i].offset));
1926                         if (ret) {
1927                                 ret = -EFAULT;
1928                                 DRM_DEBUG("failed to copy %d exec entries "
1929                                           "back to user\n",
1930                                           args->buffer_count);
1931                                 break;
1932                         }
1933                 }
1934         }
1935
1936         drm_free_large(exec2_list);
1937         return ret;
1938 }