]> git.karo-electronics.de Git - mv-sheeva.git/blob - drivers/gpu/drm/i915/i915_gem_execbuffer.c
[SCSI] target: Add LIO target core v4.0.0-rc6
[mv-sheeva.git] / 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 <eric@anholt.net>
25  *    Chris Wilson <chris@chris-wilson.co.uk>
26  *
27  */
28
29 #include "drmP.h"
30 #include "drm.h"
31 #include "i915_drm.h"
32 #include "i915_drv.h"
33 #include "i915_trace.h"
34 #include "intel_drv.h"
35
36 struct change_domains {
37         uint32_t invalidate_domains;
38         uint32_t flush_domains;
39         uint32_t flush_rings;
40 };
41
42 /*
43  * Set the next domain for the specified object. This
44  * may not actually perform the necessary flushing/invaliding though,
45  * as that may want to be batched with other set_domain operations
46  *
47  * This is (we hope) the only really tricky part of gem. The goal
48  * is fairly simple -- track which caches hold bits of the object
49  * and make sure they remain coherent. A few concrete examples may
50  * help to explain how it works. For shorthand, we use the notation
51  * (read_domains, write_domain), e.g. (CPU, CPU) to indicate the
52  * a pair of read and write domain masks.
53  *
54  * Case 1: the batch buffer
55  *
56  *      1. Allocated
57  *      2. Written by CPU
58  *      3. Mapped to GTT
59  *      4. Read by GPU
60  *      5. Unmapped from GTT
61  *      6. Freed
62  *
63  *      Let's take these a step at a time
64  *
65  *      1. Allocated
66  *              Pages allocated from the kernel may still have
67  *              cache contents, so we set them to (CPU, CPU) always.
68  *      2. Written by CPU (using pwrite)
69  *              The pwrite function calls set_domain (CPU, CPU) and
70  *              this function does nothing (as nothing changes)
71  *      3. Mapped by GTT
72  *              This function asserts that the object is not
73  *              currently in any GPU-based read or write domains
74  *      4. Read by GPU
75  *              i915_gem_execbuffer calls set_domain (COMMAND, 0).
76  *              As write_domain is zero, this function adds in the
77  *              current read domains (CPU+COMMAND, 0).
78  *              flush_domains is set to CPU.
79  *              invalidate_domains is set to COMMAND
80  *              clflush is run to get data out of the CPU caches
81  *              then i915_dev_set_domain calls i915_gem_flush to
82  *              emit an MI_FLUSH and drm_agp_chipset_flush
83  *      5. Unmapped from GTT
84  *              i915_gem_object_unbind calls set_domain (CPU, CPU)
85  *              flush_domains and invalidate_domains end up both zero
86  *              so no flushing/invalidating happens
87  *      6. Freed
88  *              yay, done
89  *
90  * Case 2: The shared render buffer
91  *
92  *      1. Allocated
93  *      2. Mapped to GTT
94  *      3. Read/written by GPU
95  *      4. set_domain to (CPU,CPU)
96  *      5. Read/written by CPU
97  *      6. Read/written by GPU
98  *
99  *      1. Allocated
100  *              Same as last example, (CPU, CPU)
101  *      2. Mapped to GTT
102  *              Nothing changes (assertions find that it is not in the GPU)
103  *      3. Read/written by GPU
104  *              execbuffer calls set_domain (RENDER, RENDER)
105  *              flush_domains gets CPU
106  *              invalidate_domains gets GPU
107  *              clflush (obj)
108  *              MI_FLUSH and drm_agp_chipset_flush
109  *      4. set_domain (CPU, CPU)
110  *              flush_domains gets GPU
111  *              invalidate_domains gets CPU
112  *              wait_rendering (obj) to make sure all drawing is complete.
113  *              This will include an MI_FLUSH to get the data from GPU
114  *              to memory
115  *              clflush (obj) to invalidate the CPU cache
116  *              Another MI_FLUSH in i915_gem_flush (eliminate this somehow?)
117  *      5. Read/written by CPU
118  *              cache lines are loaded and dirtied
119  *      6. Read written by GPU
120  *              Same as last GPU access
121  *
122  * Case 3: The constant buffer
123  *
124  *      1. Allocated
125  *      2. Written by CPU
126  *      3. Read by GPU
127  *      4. Updated (written) by CPU again
128  *      5. Read by GPU
129  *
130  *      1. Allocated
131  *              (CPU, CPU)
132  *      2. Written by CPU
133  *              (CPU, CPU)
134  *      3. Read by GPU
135  *              (CPU+RENDER, 0)
136  *              flush_domains = CPU
137  *              invalidate_domains = RENDER
138  *              clflush (obj)
139  *              MI_FLUSH
140  *              drm_agp_chipset_flush
141  *      4. Updated (written) by CPU again
142  *              (CPU, CPU)
143  *              flush_domains = 0 (no previous write domain)
144  *              invalidate_domains = 0 (no new read domains)
145  *      5. Read by GPU
146  *              (CPU+RENDER, 0)
147  *              flush_domains = CPU
148  *              invalidate_domains = RENDER
149  *              clflush (obj)
150  *              MI_FLUSH
151  *              drm_agp_chipset_flush
152  */
153 static void
154 i915_gem_object_set_to_gpu_domain(struct drm_i915_gem_object *obj,
155                                   struct intel_ring_buffer *ring,
156                                   struct change_domains *cd)
157 {
158         uint32_t invalidate_domains = 0, flush_domains = 0;
159
160         /*
161          * If the object isn't moving to a new write domain,
162          * let the object stay in multiple read domains
163          */
164         if (obj->base.pending_write_domain == 0)
165                 obj->base.pending_read_domains |= obj->base.read_domains;
166
167         /*
168          * Flush the current write domain if
169          * the new read domains don't match. Invalidate
170          * any read domains which differ from the old
171          * write domain
172          */
173         if (obj->base.write_domain &&
174             (((obj->base.write_domain != obj->base.pending_read_domains ||
175                obj->ring != ring)) ||
176              (obj->fenced_gpu_access && !obj->pending_fenced_gpu_access))) {
177                 flush_domains |= obj->base.write_domain;
178                 invalidate_domains |=
179                         obj->base.pending_read_domains & ~obj->base.write_domain;
180         }
181         /*
182          * Invalidate any read caches which may have
183          * stale data. That is, any new read domains.
184          */
185         invalidate_domains |= obj->base.pending_read_domains & ~obj->base.read_domains;
186         if ((flush_domains | invalidate_domains) & I915_GEM_DOMAIN_CPU)
187                 i915_gem_clflush_object(obj);
188
189         /* blow away mappings if mapped through GTT */
190         if ((flush_domains | invalidate_domains) & I915_GEM_DOMAIN_GTT)
191                 i915_gem_release_mmap(obj);
192
193         /* The actual obj->write_domain will be updated with
194          * pending_write_domain after we emit the accumulated flush for all
195          * of our domain changes in execbuffers (which clears objects'
196          * write_domains).  So if we have a current write domain that we
197          * aren't changing, set pending_write_domain to that.
198          */
199         if (flush_domains == 0 && obj->base.pending_write_domain == 0)
200                 obj->base.pending_write_domain = obj->base.write_domain;
201
202         cd->invalidate_domains |= invalidate_domains;
203         cd->flush_domains |= flush_domains;
204         if (flush_domains & I915_GEM_GPU_DOMAINS)
205                 cd->flush_rings |= obj->ring->id;
206         if (invalidate_domains & I915_GEM_GPU_DOMAINS)
207                 cd->flush_rings |= ring->id;
208 }
209
210 struct eb_objects {
211         int and;
212         struct hlist_head buckets[0];
213 };
214
215 static struct eb_objects *
216 eb_create(int size)
217 {
218         struct eb_objects *eb;
219         int count = PAGE_SIZE / sizeof(struct hlist_head) / 2;
220         while (count > size)
221                 count >>= 1;
222         eb = kzalloc(count*sizeof(struct hlist_head) +
223                      sizeof(struct eb_objects),
224                      GFP_KERNEL);
225         if (eb == NULL)
226                 return eb;
227
228         eb->and = count - 1;
229         return eb;
230 }
231
232 static void
233 eb_reset(struct eb_objects *eb)
234 {
235         memset(eb->buckets, 0, (eb->and+1)*sizeof(struct hlist_head));
236 }
237
238 static void
239 eb_add_object(struct eb_objects *eb, struct drm_i915_gem_object *obj)
240 {
241         hlist_add_head(&obj->exec_node,
242                        &eb->buckets[obj->exec_handle & eb->and]);
243 }
244
245 static struct drm_i915_gem_object *
246 eb_get_object(struct eb_objects *eb, unsigned long handle)
247 {
248         struct hlist_head *head;
249         struct hlist_node *node;
250         struct drm_i915_gem_object *obj;
251
252         head = &eb->buckets[handle & eb->and];
253         hlist_for_each(node, head) {
254                 obj = hlist_entry(node, struct drm_i915_gem_object, exec_node);
255                 if (obj->exec_handle == handle)
256                         return obj;
257         }
258
259         return NULL;
260 }
261
262 static void
263 eb_destroy(struct eb_objects *eb)
264 {
265         kfree(eb);
266 }
267
268 static int
269 i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj,
270                                    struct eb_objects *eb,
271                                    struct drm_i915_gem_relocation_entry *reloc)
272 {
273         struct drm_device *dev = obj->base.dev;
274         struct drm_gem_object *target_obj;
275         uint32_t target_offset;
276         int ret = -EINVAL;
277
278         /* we've already hold a reference to all valid objects */
279         target_obj = &eb_get_object(eb, reloc->target_handle)->base;
280         if (unlikely(target_obj == NULL))
281                 return -ENOENT;
282
283         target_offset = to_intel_bo(target_obj)->gtt_offset;
284
285 #if WATCH_RELOC
286         DRM_INFO("%s: obj %p offset %08x target %d "
287                  "read %08x write %08x gtt %08x "
288                  "presumed %08x delta %08x\n",
289                  __func__,
290                  obj,
291                  (int) reloc->offset,
292                  (int) reloc->target_handle,
293                  (int) reloc->read_domains,
294                  (int) reloc->write_domain,
295                  (int) target_offset,
296                  (int) reloc->presumed_offset,
297                  reloc->delta);
298 #endif
299
300         /* The target buffer should have appeared before us in the
301          * exec_object list, so it should have a GTT space bound by now.
302          */
303         if (unlikely(target_offset == 0)) {
304                 DRM_ERROR("No GTT space found for object %d\n",
305                           reloc->target_handle);
306                 return ret;
307         }
308
309         /* Validate that the target is in a valid r/w GPU domain */
310         if (unlikely(reloc->write_domain & (reloc->write_domain - 1))) {
311                 DRM_ERROR("reloc with multiple write domains: "
312                           "obj %p target %d offset %d "
313                           "read %08x write %08x",
314                           obj, reloc->target_handle,
315                           (int) reloc->offset,
316                           reloc->read_domains,
317                           reloc->write_domain);
318                 return ret;
319         }
320         if (unlikely((reloc->write_domain | reloc->read_domains) & I915_GEM_DOMAIN_CPU)) {
321                 DRM_ERROR("reloc with read/write CPU domains: "
322                           "obj %p target %d offset %d "
323                           "read %08x write %08x",
324                           obj, reloc->target_handle,
325                           (int) reloc->offset,
326                           reloc->read_domains,
327                           reloc->write_domain);
328                 return ret;
329         }
330         if (unlikely(reloc->write_domain && target_obj->pending_write_domain &&
331                      reloc->write_domain != target_obj->pending_write_domain)) {
332                 DRM_ERROR("Write domain conflict: "
333                           "obj %p target %d offset %d "
334                           "new %08x old %08x\n",
335                           obj, reloc->target_handle,
336                           (int) reloc->offset,
337                           reloc->write_domain,
338                           target_obj->pending_write_domain);
339                 return ret;
340         }
341
342         target_obj->pending_read_domains |= reloc->read_domains;
343         target_obj->pending_write_domain |= reloc->write_domain;
344
345         /* If the relocation already has the right value in it, no
346          * more work needs to be done.
347          */
348         if (target_offset == reloc->presumed_offset)
349                 return 0;
350
351         /* Check that the relocation address is valid... */
352         if (unlikely(reloc->offset > obj->base.size - 4)) {
353                 DRM_ERROR("Relocation beyond object bounds: "
354                           "obj %p target %d offset %d size %d.\n",
355                           obj, reloc->target_handle,
356                           (int) reloc->offset,
357                           (int) obj->base.size);
358                 return ret;
359         }
360         if (unlikely(reloc->offset & 3)) {
361                 DRM_ERROR("Relocation not 4-byte aligned: "
362                           "obj %p target %d offset %d.\n",
363                           obj, reloc->target_handle,
364                           (int) reloc->offset);
365                 return ret;
366         }
367
368         /* and points to somewhere within the target object. */
369         if (unlikely(reloc->delta >= target_obj->size)) {
370                 DRM_ERROR("Relocation beyond target object bounds: "
371                           "obj %p target %d delta %d size %d.\n",
372                           obj, reloc->target_handle,
373                           (int) reloc->delta,
374                           (int) target_obj->size);
375                 return ret;
376         }
377
378         reloc->delta += target_offset;
379         if (obj->base.write_domain == I915_GEM_DOMAIN_CPU) {
380                 uint32_t page_offset = reloc->offset & ~PAGE_MASK;
381                 char *vaddr;
382
383                 vaddr = kmap_atomic(obj->pages[reloc->offset >> PAGE_SHIFT]);
384                 *(uint32_t *)(vaddr + page_offset) = reloc->delta;
385                 kunmap_atomic(vaddr);
386         } else {
387                 struct drm_i915_private *dev_priv = dev->dev_private;
388                 uint32_t __iomem *reloc_entry;
389                 void __iomem *reloc_page;
390
391                 ret = i915_gem_object_set_to_gtt_domain(obj, 1);
392                 if (ret)
393                         return ret;
394
395                 /* Map the page containing the relocation we're going to perform.  */
396                 reloc->offset += obj->gtt_offset;
397                 reloc_page = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping,
398                                                       reloc->offset & PAGE_MASK);
399                 reloc_entry = (uint32_t __iomem *)
400                         (reloc_page + (reloc->offset & ~PAGE_MASK));
401                 iowrite32(reloc->delta, reloc_entry);
402                 io_mapping_unmap_atomic(reloc_page);
403         }
404
405         /* and update the user's relocation entry */
406         reloc->presumed_offset = target_offset;
407
408         return 0;
409 }
410
411 static int
412 i915_gem_execbuffer_relocate_object(struct drm_i915_gem_object *obj,
413                                     struct eb_objects *eb)
414 {
415         struct drm_i915_gem_relocation_entry __user *user_relocs;
416         struct drm_i915_gem_exec_object2 *entry = obj->exec_entry;
417         int i, ret;
418
419         user_relocs = (void __user *)(uintptr_t)entry->relocs_ptr;
420         for (i = 0; i < entry->relocation_count; i++) {
421                 struct drm_i915_gem_relocation_entry reloc;
422
423                 if (__copy_from_user_inatomic(&reloc,
424                                               user_relocs+i,
425                                               sizeof(reloc)))
426                         return -EFAULT;
427
428                 ret = i915_gem_execbuffer_relocate_entry(obj, eb, &reloc);
429                 if (ret)
430                         return ret;
431
432                 if (__copy_to_user_inatomic(&user_relocs[i].presumed_offset,
433                                             &reloc.presumed_offset,
434                                             sizeof(reloc.presumed_offset)))
435                         return -EFAULT;
436         }
437
438         return 0;
439 }
440
441 static int
442 i915_gem_execbuffer_relocate_object_slow(struct drm_i915_gem_object *obj,
443                                          struct eb_objects *eb,
444                                          struct drm_i915_gem_relocation_entry *relocs)
445 {
446         const struct drm_i915_gem_exec_object2 *entry = obj->exec_entry;
447         int i, ret;
448
449         for (i = 0; i < entry->relocation_count; i++) {
450                 ret = i915_gem_execbuffer_relocate_entry(obj, eb, &relocs[i]);
451                 if (ret)
452                         return ret;
453         }
454
455         return 0;
456 }
457
458 static int
459 i915_gem_execbuffer_relocate(struct drm_device *dev,
460                              struct eb_objects *eb,
461                              struct list_head *objects)
462 {
463         struct drm_i915_gem_object *obj;
464         int ret;
465
466         list_for_each_entry(obj, objects, exec_list) {
467                 obj->base.pending_read_domains = 0;
468                 obj->base.pending_write_domain = 0;
469                 ret = i915_gem_execbuffer_relocate_object(obj, eb);
470                 if (ret)
471                         return ret;
472         }
473
474         return 0;
475 }
476
477 static int
478 i915_gem_execbuffer_reserve(struct intel_ring_buffer *ring,
479                             struct drm_file *file,
480                             struct list_head *objects)
481 {
482         struct drm_i915_gem_object *obj;
483         int ret, retry;
484         bool has_fenced_gpu_access = INTEL_INFO(ring->dev)->gen < 4;
485         struct list_head ordered_objects;
486
487         INIT_LIST_HEAD(&ordered_objects);
488         while (!list_empty(objects)) {
489                 struct drm_i915_gem_exec_object2 *entry;
490                 bool need_fence, need_mappable;
491
492                 obj = list_first_entry(objects,
493                                        struct drm_i915_gem_object,
494                                        exec_list);
495                 entry = obj->exec_entry;
496
497                 need_fence =
498                         has_fenced_gpu_access &&
499                         entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
500                         obj->tiling_mode != I915_TILING_NONE;
501                 need_mappable =
502                         entry->relocation_count ? true : need_fence;
503
504                 if (need_mappable)
505                         list_move(&obj->exec_list, &ordered_objects);
506                 else
507                         list_move_tail(&obj->exec_list, &ordered_objects);
508         }
509         list_splice(&ordered_objects, objects);
510
511         /* Attempt to pin all of the buffers into the GTT.
512          * This is done in 3 phases:
513          *
514          * 1a. Unbind all objects that do not match the GTT constraints for
515          *     the execbuffer (fenceable, mappable, alignment etc).
516          * 1b. Increment pin count for already bound objects.
517          * 2.  Bind new objects.
518          * 3.  Decrement pin count.
519          *
520          * This avoid unnecessary unbinding of later objects in order to makr
521          * room for the earlier objects *unless* we need to defragment.
522          */
523         retry = 0;
524         do {
525                 ret = 0;
526
527                 /* Unbind any ill-fitting objects or pin. */
528                 list_for_each_entry(obj, objects, exec_list) {
529                         struct drm_i915_gem_exec_object2 *entry = obj->exec_entry;
530                         bool need_fence, need_mappable;
531                         if (!obj->gtt_space)
532                                 continue;
533
534                         need_fence =
535                                 has_fenced_gpu_access &&
536                                 entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
537                                 obj->tiling_mode != I915_TILING_NONE;
538                         need_mappable =
539                                 entry->relocation_count ? true : need_fence;
540
541                         if ((entry->alignment && obj->gtt_offset & (entry->alignment - 1)) ||
542                             (need_mappable && !obj->map_and_fenceable))
543                                 ret = i915_gem_object_unbind(obj);
544                         else
545                                 ret = i915_gem_object_pin(obj,
546                                                           entry->alignment,
547                                                           need_mappable);
548                         if (ret)
549                                 goto err;
550
551                         entry++;
552                 }
553
554                 /* Bind fresh objects */
555                 list_for_each_entry(obj, objects, exec_list) {
556                         struct drm_i915_gem_exec_object2 *entry = obj->exec_entry;
557                         bool need_fence;
558
559                         need_fence =
560                                 has_fenced_gpu_access &&
561                                 entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
562                                 obj->tiling_mode != I915_TILING_NONE;
563
564                         if (!obj->gtt_space) {
565                                 bool need_mappable =
566                                         entry->relocation_count ? true : need_fence;
567
568                                 ret = i915_gem_object_pin(obj,
569                                                           entry->alignment,
570                                                           need_mappable);
571                                 if (ret)
572                                         break;
573                         }
574
575                         if (has_fenced_gpu_access) {
576                                 if (need_fence) {
577                                         ret = i915_gem_object_get_fence(obj, ring, 1);
578                                         if (ret)
579                                                 break;
580                                 } else if (entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
581                                            obj->tiling_mode == I915_TILING_NONE) {
582                                         /* XXX pipelined! */
583                                         ret = i915_gem_object_put_fence(obj);
584                                         if (ret)
585                                                 break;
586                                 }
587                                 obj->pending_fenced_gpu_access = need_fence;
588                         }
589
590                         entry->offset = obj->gtt_offset;
591                 }
592
593                 /* Decrement pin count for bound objects */
594                 list_for_each_entry(obj, objects, exec_list) {
595                         if (obj->gtt_space)
596                                 i915_gem_object_unpin(obj);
597                 }
598
599                 if (ret != -ENOSPC || retry > 1)
600                         return ret;
601
602                 /* First attempt, just clear anything that is purgeable.
603                  * Second attempt, clear the entire GTT.
604                  */
605                 ret = i915_gem_evict_everything(ring->dev, retry == 0);
606                 if (ret)
607                         return ret;
608
609                 retry++;
610         } while (1);
611
612 err:
613         obj = list_entry(obj->exec_list.prev,
614                          struct drm_i915_gem_object,
615                          exec_list);
616         while (objects != &obj->exec_list) {
617                 if (obj->gtt_space)
618                         i915_gem_object_unpin(obj);
619
620                 obj = list_entry(obj->exec_list.prev,
621                                  struct drm_i915_gem_object,
622                                  exec_list);
623         }
624
625         return ret;
626 }
627
628 static int
629 i915_gem_execbuffer_relocate_slow(struct drm_device *dev,
630                                   struct drm_file *file,
631                                   struct intel_ring_buffer *ring,
632                                   struct list_head *objects,
633                                   struct eb_objects *eb,
634                                   struct drm_i915_gem_exec_object2 *exec,
635                                   int count)
636 {
637         struct drm_i915_gem_relocation_entry *reloc;
638         struct drm_i915_gem_object *obj;
639         int i, total, ret;
640
641         /* We may process another execbuffer during the unlock... */
642         while (!list_empty(objects)) {
643                 obj = list_first_entry(objects,
644                                        struct drm_i915_gem_object,
645                                        exec_list);
646                 list_del_init(&obj->exec_list);
647                 drm_gem_object_unreference(&obj->base);
648         }
649
650         mutex_unlock(&dev->struct_mutex);
651
652         total = 0;
653         for (i = 0; i < count; i++)
654                 total += exec[i].relocation_count;
655
656         reloc = drm_malloc_ab(total, sizeof(*reloc));
657         if (reloc == NULL) {
658                 mutex_lock(&dev->struct_mutex);
659                 return -ENOMEM;
660         }
661
662         total = 0;
663         for (i = 0; i < count; i++) {
664                 struct drm_i915_gem_relocation_entry __user *user_relocs;
665
666                 user_relocs = (void __user *)(uintptr_t)exec[i].relocs_ptr;
667
668                 if (copy_from_user(reloc+total, user_relocs,
669                                    exec[i].relocation_count * sizeof(*reloc))) {
670                         ret = -EFAULT;
671                         mutex_lock(&dev->struct_mutex);
672                         goto err;
673                 }
674
675                 total += exec[i].relocation_count;
676         }
677
678         ret = i915_mutex_lock_interruptible(dev);
679         if (ret) {
680                 mutex_lock(&dev->struct_mutex);
681                 goto err;
682         }
683
684         /* reacquire the objects */
685         eb_reset(eb);
686         for (i = 0; i < count; i++) {
687                 struct drm_i915_gem_object *obj;
688
689                 obj = to_intel_bo(drm_gem_object_lookup(dev, file,
690                                                         exec[i].handle));
691                 if (obj == NULL) {
692                         DRM_ERROR("Invalid object handle %d at index %d\n",
693                                    exec[i].handle, i);
694                         ret = -ENOENT;
695                         goto err;
696                 }
697
698                 list_add_tail(&obj->exec_list, objects);
699                 obj->exec_handle = exec[i].handle;
700                 obj->exec_entry = &exec[i];
701                 eb_add_object(eb, obj);
702         }
703
704         ret = i915_gem_execbuffer_reserve(ring, file, objects);
705         if (ret)
706                 goto err;
707
708         total = 0;
709         list_for_each_entry(obj, objects, exec_list) {
710                 obj->base.pending_read_domains = 0;
711                 obj->base.pending_write_domain = 0;
712                 ret = i915_gem_execbuffer_relocate_object_slow(obj, eb,
713                                                                reloc + total);
714                 if (ret)
715                         goto err;
716
717                 total += exec->relocation_count;
718                 exec++;
719         }
720
721         /* Leave the user relocations as are, this is the painfully slow path,
722          * and we want to avoid the complication of dropping the lock whilst
723          * having buffers reserved in the aperture and so causing spurious
724          * ENOSPC for random operations.
725          */
726
727 err:
728         drm_free_large(reloc);
729         return ret;
730 }
731
732 static int
733 i915_gem_execbuffer_flush(struct drm_device *dev,
734                           uint32_t invalidate_domains,
735                           uint32_t flush_domains,
736                           uint32_t flush_rings)
737 {
738         drm_i915_private_t *dev_priv = dev->dev_private;
739         int i, ret;
740
741         if (flush_domains & I915_GEM_DOMAIN_CPU)
742                 intel_gtt_chipset_flush();
743
744         if (flush_domains & I915_GEM_DOMAIN_GTT)
745                 wmb();
746
747         if ((flush_domains | invalidate_domains) & I915_GEM_GPU_DOMAINS) {
748                 for (i = 0; i < I915_NUM_RINGS; i++)
749                         if (flush_rings & (1 << i)) {
750                                 ret = i915_gem_flush_ring(dev,
751                                                           &dev_priv->ring[i],
752                                                           invalidate_domains,
753                                                           flush_domains);
754                                 if (ret)
755                                         return ret;
756                         }
757         }
758
759         return 0;
760 }
761
762 static int
763 i915_gem_execbuffer_sync_rings(struct drm_i915_gem_object *obj,
764                                struct intel_ring_buffer *to)
765 {
766         struct intel_ring_buffer *from = obj->ring;
767         u32 seqno;
768         int ret, idx;
769
770         if (from == NULL || to == from)
771                 return 0;
772
773         if (INTEL_INFO(obj->base.dev)->gen < 6)
774                 return i915_gem_object_wait_rendering(obj, true);
775
776         idx = intel_ring_sync_index(from, to);
777
778         seqno = obj->last_rendering_seqno;
779         if (seqno <= from->sync_seqno[idx])
780                 return 0;
781
782         if (seqno == from->outstanding_lazy_request) {
783                 struct drm_i915_gem_request *request;
784
785                 request = kzalloc(sizeof(*request), GFP_KERNEL);
786                 if (request == NULL)
787                         return -ENOMEM;
788
789                 ret = i915_add_request(obj->base.dev, NULL, request, from);
790                 if (ret) {
791                         kfree(request);
792                         return ret;
793                 }
794
795                 seqno = request->seqno;
796         }
797
798         from->sync_seqno[idx] = seqno;
799         return intel_ring_sync(to, from, seqno - 1);
800 }
801
802 static int
803 i915_gem_execbuffer_move_to_gpu(struct intel_ring_buffer *ring,
804                                 struct list_head *objects)
805 {
806         struct drm_i915_gem_object *obj;
807         struct change_domains cd;
808         int ret;
809
810         cd.invalidate_domains = 0;
811         cd.flush_domains = 0;
812         cd.flush_rings = 0;
813         list_for_each_entry(obj, objects, exec_list)
814                 i915_gem_object_set_to_gpu_domain(obj, ring, &cd);
815
816         if (cd.invalidate_domains | cd.flush_domains) {
817 #if WATCH_EXEC
818                 DRM_INFO("%s: invalidate_domains %08x flush_domains %08x\n",
819                           __func__,
820                          cd.invalidate_domains,
821                          cd.flush_domains);
822 #endif
823                 ret = i915_gem_execbuffer_flush(ring->dev,
824                                                 cd.invalidate_domains,
825                                                 cd.flush_domains,
826                                                 cd.flush_rings);
827                 if (ret)
828                         return ret;
829         }
830
831         list_for_each_entry(obj, objects, exec_list) {
832                 ret = i915_gem_execbuffer_sync_rings(obj, ring);
833                 if (ret)
834                         return ret;
835         }
836
837         return 0;
838 }
839
840 static bool
841 i915_gem_check_execbuffer(struct drm_i915_gem_execbuffer2 *exec)
842 {
843         return ((exec->batch_start_offset | exec->batch_len) & 0x7) == 0;
844 }
845
846 static int
847 validate_exec_list(struct drm_i915_gem_exec_object2 *exec,
848                    int count)
849 {
850         int i;
851
852         for (i = 0; i < count; i++) {
853                 char __user *ptr = (char __user *)(uintptr_t)exec[i].relocs_ptr;
854                 int length; /* limited by fault_in_pages_readable() */
855
856                 /* First check for malicious input causing overflow */
857                 if (exec[i].relocation_count >
858                     INT_MAX / sizeof(struct drm_i915_gem_relocation_entry))
859                         return -EINVAL;
860
861                 length = exec[i].relocation_count *
862                         sizeof(struct drm_i915_gem_relocation_entry);
863                 if (!access_ok(VERIFY_READ, ptr, length))
864                         return -EFAULT;
865
866                 /* we may also need to update the presumed offsets */
867                 if (!access_ok(VERIFY_WRITE, ptr, length))
868                         return -EFAULT;
869
870                 if (fault_in_pages_readable(ptr, length))
871                         return -EFAULT;
872         }
873
874         return 0;
875 }
876
877 static int
878 i915_gem_execbuffer_wait_for_flips(struct intel_ring_buffer *ring,
879                                    struct list_head *objects)
880 {
881         struct drm_i915_gem_object *obj;
882         int flips;
883
884         /* Check for any pending flips. As we only maintain a flip queue depth
885          * of 1, we can simply insert a WAIT for the next display flip prior
886          * to executing the batch and avoid stalling the CPU.
887          */
888         flips = 0;
889         list_for_each_entry(obj, objects, exec_list) {
890                 if (obj->base.write_domain)
891                         flips |= atomic_read(&obj->pending_flip);
892         }
893         if (flips) {
894                 int plane, flip_mask, ret;
895
896                 for (plane = 0; flips >> plane; plane++) {
897                         if (((flips >> plane) & 1) == 0)
898                                 continue;
899
900                         if (plane)
901                                 flip_mask = MI_WAIT_FOR_PLANE_B_FLIP;
902                         else
903                                 flip_mask = MI_WAIT_FOR_PLANE_A_FLIP;
904
905                         ret = intel_ring_begin(ring, 2);
906                         if (ret)
907                                 return ret;
908
909                         intel_ring_emit(ring, MI_WAIT_FOR_EVENT | flip_mask);
910                         intel_ring_emit(ring, MI_NOOP);
911                         intel_ring_advance(ring);
912                 }
913         }
914
915         return 0;
916 }
917
918 static void
919 i915_gem_execbuffer_move_to_active(struct list_head *objects,
920                                    struct intel_ring_buffer *ring,
921                                    u32 seqno)
922 {
923         struct drm_i915_gem_object *obj;
924
925         list_for_each_entry(obj, objects, exec_list) {
926                 obj->base.read_domains = obj->base.pending_read_domains;
927                 obj->base.write_domain = obj->base.pending_write_domain;
928                 obj->fenced_gpu_access = obj->pending_fenced_gpu_access;
929
930                 i915_gem_object_move_to_active(obj, ring, seqno);
931                 if (obj->base.write_domain) {
932                         obj->dirty = 1;
933                         obj->pending_gpu_write = true;
934                         list_move_tail(&obj->gpu_write_list,
935                                        &ring->gpu_write_list);
936                         intel_mark_busy(ring->dev, obj);
937                 }
938
939                 trace_i915_gem_object_change_domain(obj,
940                                                     obj->base.read_domains,
941                                                     obj->base.write_domain);
942         }
943 }
944
945 static void
946 i915_gem_execbuffer_retire_commands(struct drm_device *dev,
947                                     struct drm_file *file,
948                                     struct intel_ring_buffer *ring)
949 {
950         struct drm_i915_gem_request *request;
951         u32 invalidate;
952
953         /*
954          * Ensure that the commands in the batch buffer are
955          * finished before the interrupt fires.
956          *
957          * The sampler always gets flushed on i965 (sigh).
958          */
959         invalidate = I915_GEM_DOMAIN_COMMAND;
960         if (INTEL_INFO(dev)->gen >= 4)
961                 invalidate |= I915_GEM_DOMAIN_SAMPLER;
962         if (ring->flush(ring, invalidate, 0)) {
963                 i915_gem_next_request_seqno(dev, ring);
964                 return;
965         }
966
967         /* Add a breadcrumb for the completion of the batch buffer */
968         request = kzalloc(sizeof(*request), GFP_KERNEL);
969         if (request == NULL || i915_add_request(dev, file, request, ring)) {
970                 i915_gem_next_request_seqno(dev, ring);
971                 kfree(request);
972         }
973 }
974
975 static int
976 i915_gem_do_execbuffer(struct drm_device *dev, void *data,
977                        struct drm_file *file,
978                        struct drm_i915_gem_execbuffer2 *args,
979                        struct drm_i915_gem_exec_object2 *exec)
980 {
981         drm_i915_private_t *dev_priv = dev->dev_private;
982         struct list_head objects;
983         struct eb_objects *eb;
984         struct drm_i915_gem_object *batch_obj;
985         struct drm_clip_rect *cliprects = NULL;
986         struct intel_ring_buffer *ring;
987         u32 exec_start, exec_len;
988         u32 seqno;
989         int ret, mode, i;
990
991         if (!i915_gem_check_execbuffer(args)) {
992                 DRM_ERROR("execbuf with invalid offset/length\n");
993                 return -EINVAL;
994         }
995
996         ret = validate_exec_list(exec, args->buffer_count);
997         if (ret)
998                 return ret;
999
1000 #if WATCH_EXEC
1001         DRM_INFO("buffers_ptr %d buffer_count %d len %08x\n",
1002                   (int) args->buffers_ptr, args->buffer_count, args->batch_len);
1003 #endif
1004         switch (args->flags & I915_EXEC_RING_MASK) {
1005         case I915_EXEC_DEFAULT:
1006         case I915_EXEC_RENDER:
1007                 ring = &dev_priv->ring[RCS];
1008                 break;
1009         case I915_EXEC_BSD:
1010                 if (!HAS_BSD(dev)) {
1011                         DRM_ERROR("execbuf with invalid ring (BSD)\n");
1012                         return -EINVAL;
1013                 }
1014                 ring = &dev_priv->ring[VCS];
1015                 break;
1016         case I915_EXEC_BLT:
1017                 if (!HAS_BLT(dev)) {
1018                         DRM_ERROR("execbuf with invalid ring (BLT)\n");
1019                         return -EINVAL;
1020                 }
1021                 ring = &dev_priv->ring[BCS];
1022                 break;
1023         default:
1024                 DRM_ERROR("execbuf with unknown ring: %d\n",
1025                           (int)(args->flags & I915_EXEC_RING_MASK));
1026                 return -EINVAL;
1027         }
1028
1029         mode = args->flags & I915_EXEC_CONSTANTS_MASK;
1030         switch (mode) {
1031         case I915_EXEC_CONSTANTS_REL_GENERAL:
1032         case I915_EXEC_CONSTANTS_ABSOLUTE:
1033         case I915_EXEC_CONSTANTS_REL_SURFACE:
1034                 if (ring == &dev_priv->ring[RCS] &&
1035                     mode != dev_priv->relative_constants_mode) {
1036                         if (INTEL_INFO(dev)->gen < 4)
1037                                 return -EINVAL;
1038
1039                         if (INTEL_INFO(dev)->gen > 5 &&
1040                             mode == I915_EXEC_CONSTANTS_REL_SURFACE)
1041                                 return -EINVAL;
1042
1043                         ret = intel_ring_begin(ring, 4);
1044                         if (ret)
1045                                 return ret;
1046
1047                         intel_ring_emit(ring, MI_NOOP);
1048                         intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
1049                         intel_ring_emit(ring, INSTPM);
1050                         intel_ring_emit(ring,
1051                                         I915_EXEC_CONSTANTS_MASK << 16 | mode);
1052                         intel_ring_advance(ring);
1053
1054                         dev_priv->relative_constants_mode = mode;
1055                 }
1056                 break;
1057         default:
1058                 DRM_ERROR("execbuf with unknown constants: %d\n", mode);
1059                 return -EINVAL;
1060         }
1061
1062         if (args->buffer_count < 1) {
1063                 DRM_ERROR("execbuf with %d buffers\n", args->buffer_count);
1064                 return -EINVAL;
1065         }
1066
1067         if (args->num_cliprects != 0) {
1068                 if (ring != &dev_priv->ring[RCS]) {
1069                         DRM_ERROR("clip rectangles are only valid with the render ring\n");
1070                         return -EINVAL;
1071                 }
1072
1073                 cliprects = kmalloc(args->num_cliprects * sizeof(*cliprects),
1074                                     GFP_KERNEL);
1075                 if (cliprects == NULL) {
1076                         ret = -ENOMEM;
1077                         goto pre_mutex_err;
1078                 }
1079
1080                 if (copy_from_user(cliprects,
1081                                      (struct drm_clip_rect __user *)(uintptr_t)
1082                                      args->cliprects_ptr,
1083                                      sizeof(*cliprects)*args->num_cliprects)) {
1084                         ret = -EFAULT;
1085                         goto pre_mutex_err;
1086                 }
1087         }
1088
1089         ret = i915_mutex_lock_interruptible(dev);
1090         if (ret)
1091                 goto pre_mutex_err;
1092
1093         if (dev_priv->mm.suspended) {
1094                 mutex_unlock(&dev->struct_mutex);
1095                 ret = -EBUSY;
1096                 goto pre_mutex_err;
1097         }
1098
1099         eb = eb_create(args->buffer_count);
1100         if (eb == NULL) {
1101                 mutex_unlock(&dev->struct_mutex);
1102                 ret = -ENOMEM;
1103                 goto pre_mutex_err;
1104         }
1105
1106         /* Look up object handles */
1107         INIT_LIST_HEAD(&objects);
1108         for (i = 0; i < args->buffer_count; i++) {
1109                 struct drm_i915_gem_object *obj;
1110
1111                 obj = to_intel_bo(drm_gem_object_lookup(dev, file,
1112                                                         exec[i].handle));
1113                 if (obj == NULL) {
1114                         DRM_ERROR("Invalid object handle %d at index %d\n",
1115                                    exec[i].handle, i);
1116                         /* prevent error path from reading uninitialized data */
1117                         ret = -ENOENT;
1118                         goto err;
1119                 }
1120
1121                 if (!list_empty(&obj->exec_list)) {
1122                         DRM_ERROR("Object %p [handle %d, index %d] appears more than once in object list\n",
1123                                    obj, exec[i].handle, i);
1124                         ret = -EINVAL;
1125                         goto err;
1126                 }
1127
1128                 list_add_tail(&obj->exec_list, &objects);
1129                 obj->exec_handle = exec[i].handle;
1130                 obj->exec_entry = &exec[i];
1131                 eb_add_object(eb, obj);
1132         }
1133
1134         /* take note of the batch buffer before we might reorder the lists */
1135         batch_obj = list_entry(objects.prev,
1136                                struct drm_i915_gem_object,
1137                                exec_list);
1138
1139         /* Move the objects en-masse into the GTT, evicting if necessary. */
1140         ret = i915_gem_execbuffer_reserve(ring, file, &objects);
1141         if (ret)
1142                 goto err;
1143
1144         /* The objects are in their final locations, apply the relocations. */
1145         ret = i915_gem_execbuffer_relocate(dev, eb, &objects);
1146         if (ret) {
1147                 if (ret == -EFAULT) {
1148                         ret = i915_gem_execbuffer_relocate_slow(dev, file, ring,
1149                                                                 &objects, eb,
1150                                                                 exec,
1151                                                                 args->buffer_count);
1152                         BUG_ON(!mutex_is_locked(&dev->struct_mutex));
1153                 }
1154                 if (ret)
1155                         goto err;
1156         }
1157
1158         /* Set the pending read domains for the batch buffer to COMMAND */
1159         if (batch_obj->base.pending_write_domain) {
1160                 DRM_ERROR("Attempting to use self-modifying batch buffer\n");
1161                 ret = -EINVAL;
1162                 goto err;
1163         }
1164         batch_obj->base.pending_read_domains |= I915_GEM_DOMAIN_COMMAND;
1165
1166         ret = i915_gem_execbuffer_move_to_gpu(ring, &objects);
1167         if (ret)
1168                 goto err;
1169
1170         ret = i915_gem_execbuffer_wait_for_flips(ring, &objects);
1171         if (ret)
1172                 goto err;
1173
1174         seqno = i915_gem_next_request_seqno(dev, ring);
1175         for (i = 0; i < I915_NUM_RINGS-1; i++) {
1176                 if (seqno < ring->sync_seqno[i]) {
1177                         /* The GPU can not handle its semaphore value wrapping,
1178                          * so every billion or so execbuffers, we need to stall
1179                          * the GPU in order to reset the counters.
1180                          */
1181                         ret = i915_gpu_idle(dev);
1182                         if (ret)
1183                                 goto err;
1184
1185                         BUG_ON(ring->sync_seqno[i]);
1186                 }
1187         }
1188
1189         exec_start = batch_obj->gtt_offset + args->batch_start_offset;
1190         exec_len = args->batch_len;
1191         if (cliprects) {
1192                 for (i = 0; i < args->num_cliprects; i++) {
1193                         ret = i915_emit_box(dev, &cliprects[i],
1194                                             args->DR1, args->DR4);
1195                         if (ret)
1196                                 goto err;
1197
1198                         ret = ring->dispatch_execbuffer(ring,
1199                                                         exec_start, exec_len);
1200                         if (ret)
1201                                 goto err;
1202                 }
1203         } else {
1204                 ret = ring->dispatch_execbuffer(ring, exec_start, exec_len);
1205                 if (ret)
1206                         goto err;
1207         }
1208
1209         i915_gem_execbuffer_move_to_active(&objects, ring, seqno);
1210         i915_gem_execbuffer_retire_commands(dev, file, ring);
1211
1212 err:
1213         eb_destroy(eb);
1214         while (!list_empty(&objects)) {
1215                 struct drm_i915_gem_object *obj;
1216
1217                 obj = list_first_entry(&objects,
1218                                        struct drm_i915_gem_object,
1219                                        exec_list);
1220                 list_del_init(&obj->exec_list);
1221                 drm_gem_object_unreference(&obj->base);
1222         }
1223
1224         mutex_unlock(&dev->struct_mutex);
1225
1226 pre_mutex_err:
1227         kfree(cliprects);
1228         return ret;
1229 }
1230
1231 /*
1232  * Legacy execbuffer just creates an exec2 list from the original exec object
1233  * list array and passes it to the real function.
1234  */
1235 int
1236 i915_gem_execbuffer(struct drm_device *dev, void *data,
1237                     struct drm_file *file)
1238 {
1239         struct drm_i915_gem_execbuffer *args = data;
1240         struct drm_i915_gem_execbuffer2 exec2;
1241         struct drm_i915_gem_exec_object *exec_list = NULL;
1242         struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1243         int ret, i;
1244
1245 #if WATCH_EXEC
1246         DRM_INFO("buffers_ptr %d buffer_count %d len %08x\n",
1247                   (int) args->buffers_ptr, args->buffer_count, args->batch_len);
1248 #endif
1249
1250         if (args->buffer_count < 1) {
1251                 DRM_ERROR("execbuf with %d buffers\n", args->buffer_count);
1252                 return -EINVAL;
1253         }
1254
1255         /* Copy in the exec list from userland */
1256         exec_list = drm_malloc_ab(sizeof(*exec_list), args->buffer_count);
1257         exec2_list = drm_malloc_ab(sizeof(*exec2_list), args->buffer_count);
1258         if (exec_list == NULL || exec2_list == NULL) {
1259                 DRM_ERROR("Failed to allocate exec list for %d buffers\n",
1260                           args->buffer_count);
1261                 drm_free_large(exec_list);
1262                 drm_free_large(exec2_list);
1263                 return -ENOMEM;
1264         }
1265         ret = copy_from_user(exec_list,
1266                              (struct drm_i915_relocation_entry __user *)
1267                              (uintptr_t) args->buffers_ptr,
1268                              sizeof(*exec_list) * args->buffer_count);
1269         if (ret != 0) {
1270                 DRM_ERROR("copy %d exec entries failed %d\n",
1271                           args->buffer_count, ret);
1272                 drm_free_large(exec_list);
1273                 drm_free_large(exec2_list);
1274                 return -EFAULT;
1275         }
1276
1277         for (i = 0; i < args->buffer_count; i++) {
1278                 exec2_list[i].handle = exec_list[i].handle;
1279                 exec2_list[i].relocation_count = exec_list[i].relocation_count;
1280                 exec2_list[i].relocs_ptr = exec_list[i].relocs_ptr;
1281                 exec2_list[i].alignment = exec_list[i].alignment;
1282                 exec2_list[i].offset = exec_list[i].offset;
1283                 if (INTEL_INFO(dev)->gen < 4)
1284                         exec2_list[i].flags = EXEC_OBJECT_NEEDS_FENCE;
1285                 else
1286                         exec2_list[i].flags = 0;
1287         }
1288
1289         exec2.buffers_ptr = args->buffers_ptr;
1290         exec2.buffer_count = args->buffer_count;
1291         exec2.batch_start_offset = args->batch_start_offset;
1292         exec2.batch_len = args->batch_len;
1293         exec2.DR1 = args->DR1;
1294         exec2.DR4 = args->DR4;
1295         exec2.num_cliprects = args->num_cliprects;
1296         exec2.cliprects_ptr = args->cliprects_ptr;
1297         exec2.flags = I915_EXEC_RENDER;
1298
1299         ret = i915_gem_do_execbuffer(dev, data, file, &exec2, exec2_list);
1300         if (!ret) {
1301                 /* Copy the new buffer offsets back to the user's exec list. */
1302                 for (i = 0; i < args->buffer_count; i++)
1303                         exec_list[i].offset = exec2_list[i].offset;
1304                 /* ... and back out to userspace */
1305                 ret = copy_to_user((struct drm_i915_relocation_entry __user *)
1306                                    (uintptr_t) args->buffers_ptr,
1307                                    exec_list,
1308                                    sizeof(*exec_list) * args->buffer_count);
1309                 if (ret) {
1310                         ret = -EFAULT;
1311                         DRM_ERROR("failed to copy %d exec entries "
1312                                   "back to user (%d)\n",
1313                                   args->buffer_count, ret);
1314                 }
1315         }
1316
1317         drm_free_large(exec_list);
1318         drm_free_large(exec2_list);
1319         return ret;
1320 }
1321
1322 int
1323 i915_gem_execbuffer2(struct drm_device *dev, void *data,
1324                      struct drm_file *file)
1325 {
1326         struct drm_i915_gem_execbuffer2 *args = data;
1327         struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1328         int ret;
1329
1330 #if WATCH_EXEC
1331         DRM_INFO("buffers_ptr %d buffer_count %d len %08x\n",
1332                   (int) args->buffers_ptr, args->buffer_count, args->batch_len);
1333 #endif
1334
1335         if (args->buffer_count < 1) {
1336                 DRM_ERROR("execbuf2 with %d buffers\n", args->buffer_count);
1337                 return -EINVAL;
1338         }
1339
1340         exec2_list = drm_malloc_ab(sizeof(*exec2_list), args->buffer_count);
1341         if (exec2_list == NULL) {
1342                 DRM_ERROR("Failed to allocate exec list for %d buffers\n",
1343                           args->buffer_count);
1344                 return -ENOMEM;
1345         }
1346         ret = copy_from_user(exec2_list,
1347                              (struct drm_i915_relocation_entry __user *)
1348                              (uintptr_t) args->buffers_ptr,
1349                              sizeof(*exec2_list) * args->buffer_count);
1350         if (ret != 0) {
1351                 DRM_ERROR("copy %d exec entries failed %d\n",
1352                           args->buffer_count, ret);
1353                 drm_free_large(exec2_list);
1354                 return -EFAULT;
1355         }
1356
1357         ret = i915_gem_do_execbuffer(dev, data, file, args, exec2_list);
1358         if (!ret) {
1359                 /* Copy the new buffer offsets back to the user's exec list. */
1360                 ret = copy_to_user((struct drm_i915_relocation_entry __user *)
1361                                    (uintptr_t) args->buffers_ptr,
1362                                    exec2_list,
1363                                    sizeof(*exec2_list) * args->buffer_count);
1364                 if (ret) {
1365                         ret = -EFAULT;
1366                         DRM_ERROR("failed to copy %d exec entries "
1367                                   "back to user (%d)\n",
1368                                   args->buffer_count, ret);
1369                 }
1370         }
1371
1372         drm_free_large(exec2_list);
1373         return ret;
1374 }