drm/i915/cmdparser: Use cached vmappings
[cascardo/linux.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 <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_gem_dmabuf.h"
38 #include "i915_trace.h"
39 #include "intel_drv.h"
40 #include "intel_frontbuffer.h"
41
42 #define DBG_USE_CPU_RELOC 0 /* -1 force GTT relocs; 1 force CPU relocs */
43
44 #define  __EXEC_OBJECT_HAS_PIN          (1<<31)
45 #define  __EXEC_OBJECT_HAS_FENCE        (1<<30)
46 #define  __EXEC_OBJECT_NEEDS_MAP        (1<<29)
47 #define  __EXEC_OBJECT_NEEDS_BIAS       (1<<28)
48 #define  __EXEC_OBJECT_INTERNAL_FLAGS (0xf<<28) /* all of the above */
49
50 #define BATCH_OFFSET_BIAS (256*1024)
51
52 struct i915_execbuffer_params {
53         struct drm_device               *dev;
54         struct drm_file                 *file;
55         struct i915_vma                 *batch;
56         u32                             dispatch_flags;
57         u32                             args_batch_start_offset;
58         struct intel_engine_cs          *engine;
59         struct i915_gem_context         *ctx;
60         struct drm_i915_gem_request     *request;
61 };
62
63 struct eb_vmas {
64         struct drm_i915_private *i915;
65         struct list_head vmas;
66         int and;
67         union {
68                 struct i915_vma *lut[0];
69                 struct hlist_head buckets[0];
70         };
71 };
72
73 static struct eb_vmas *
74 eb_create(struct drm_i915_private *i915,
75           struct drm_i915_gem_execbuffer2 *args)
76 {
77         struct eb_vmas *eb = NULL;
78
79         if (args->flags & I915_EXEC_HANDLE_LUT) {
80                 unsigned size = args->buffer_count;
81                 size *= sizeof(struct i915_vma *);
82                 size += sizeof(struct eb_vmas);
83                 eb = kmalloc(size, GFP_TEMPORARY | __GFP_NOWARN | __GFP_NORETRY);
84         }
85
86         if (eb == NULL) {
87                 unsigned size = args->buffer_count;
88                 unsigned count = PAGE_SIZE / sizeof(struct hlist_head) / 2;
89                 BUILD_BUG_ON_NOT_POWER_OF_2(PAGE_SIZE / sizeof(struct hlist_head));
90                 while (count > 2*size)
91                         count >>= 1;
92                 eb = kzalloc(count*sizeof(struct hlist_head) +
93                              sizeof(struct eb_vmas),
94                              GFP_TEMPORARY);
95                 if (eb == NULL)
96                         return eb;
97
98                 eb->and = count - 1;
99         } else
100                 eb->and = -args->buffer_count;
101
102         eb->i915 = i915;
103         INIT_LIST_HEAD(&eb->vmas);
104         return eb;
105 }
106
107 static void
108 eb_reset(struct eb_vmas *eb)
109 {
110         if (eb->and >= 0)
111                 memset(eb->buckets, 0, (eb->and+1)*sizeof(struct hlist_head));
112 }
113
114 static struct i915_vma *
115 eb_get_batch(struct eb_vmas *eb)
116 {
117         struct i915_vma *vma = list_entry(eb->vmas.prev, typeof(*vma), exec_list);
118
119         /*
120          * SNA is doing fancy tricks with compressing batch buffers, which leads
121          * to negative relocation deltas. Usually that works out ok since the
122          * relocate address is still positive, except when the batch is placed
123          * very low in the GTT. Ensure this doesn't happen.
124          *
125          * Note that actual hangs have only been observed on gen7, but for
126          * paranoia do it everywhere.
127          */
128         if ((vma->exec_entry->flags & EXEC_OBJECT_PINNED) == 0)
129                 vma->exec_entry->flags |= __EXEC_OBJECT_NEEDS_BIAS;
130
131         return vma;
132 }
133
134 static int
135 eb_lookup_vmas(struct eb_vmas *eb,
136                struct drm_i915_gem_exec_object2 *exec,
137                const struct drm_i915_gem_execbuffer2 *args,
138                struct i915_address_space *vm,
139                struct drm_file *file)
140 {
141         struct drm_i915_gem_object *obj;
142         struct list_head objects;
143         int i, ret;
144
145         INIT_LIST_HEAD(&objects);
146         spin_lock(&file->table_lock);
147         /* Grab a reference to the object and release the lock so we can lookup
148          * or create the VMA without using GFP_ATOMIC */
149         for (i = 0; i < args->buffer_count; i++) {
150                 obj = to_intel_bo(idr_find(&file->object_idr, exec[i].handle));
151                 if (obj == NULL) {
152                         spin_unlock(&file->table_lock);
153                         DRM_DEBUG("Invalid object handle %d at index %d\n",
154                                    exec[i].handle, i);
155                         ret = -ENOENT;
156                         goto err;
157                 }
158
159                 if (!list_empty(&obj->obj_exec_link)) {
160                         spin_unlock(&file->table_lock);
161                         DRM_DEBUG("Object %p [handle %d, index %d] appears more than once in object list\n",
162                                    obj, exec[i].handle, i);
163                         ret = -EINVAL;
164                         goto err;
165                 }
166
167                 i915_gem_object_get(obj);
168                 list_add_tail(&obj->obj_exec_link, &objects);
169         }
170         spin_unlock(&file->table_lock);
171
172         i = 0;
173         while (!list_empty(&objects)) {
174                 struct i915_vma *vma;
175
176                 obj = list_first_entry(&objects,
177                                        struct drm_i915_gem_object,
178                                        obj_exec_link);
179
180                 /*
181                  * NOTE: We can leak any vmas created here when something fails
182                  * later on. But that's no issue since vma_unbind can deal with
183                  * vmas which are not actually bound. And since only
184                  * lookup_or_create exists as an interface to get at the vma
185                  * from the (obj, vm) we don't run the risk of creating
186                  * duplicated vmas for the same vm.
187                  */
188                 vma = i915_gem_obj_lookup_or_create_vma(obj, vm, NULL);
189                 if (unlikely(IS_ERR(vma))) {
190                         DRM_DEBUG("Failed to lookup VMA\n");
191                         ret = PTR_ERR(vma);
192                         goto err;
193                 }
194
195                 /* Transfer ownership from the objects list to the vmas list. */
196                 list_add_tail(&vma->exec_list, &eb->vmas);
197                 list_del_init(&obj->obj_exec_link);
198
199                 vma->exec_entry = &exec[i];
200                 if (eb->and < 0) {
201                         eb->lut[i] = vma;
202                 } else {
203                         uint32_t handle = args->flags & I915_EXEC_HANDLE_LUT ? i : exec[i].handle;
204                         vma->exec_handle = handle;
205                         hlist_add_head(&vma->exec_node,
206                                        &eb->buckets[handle & eb->and]);
207                 }
208                 ++i;
209         }
210
211         return 0;
212
213
214 err:
215         while (!list_empty(&objects)) {
216                 obj = list_first_entry(&objects,
217                                        struct drm_i915_gem_object,
218                                        obj_exec_link);
219                 list_del_init(&obj->obj_exec_link);
220                 i915_gem_object_put(obj);
221         }
222         /*
223          * Objects already transfered to the vmas list will be unreferenced by
224          * eb_destroy.
225          */
226
227         return ret;
228 }
229
230 static struct i915_vma *eb_get_vma(struct eb_vmas *eb, unsigned long handle)
231 {
232         if (eb->and < 0) {
233                 if (handle >= -eb->and)
234                         return NULL;
235                 return eb->lut[handle];
236         } else {
237                 struct hlist_head *head;
238                 struct i915_vma *vma;
239
240                 head = &eb->buckets[handle & eb->and];
241                 hlist_for_each_entry(vma, head, exec_node) {
242                         if (vma->exec_handle == handle)
243                                 return vma;
244                 }
245                 return NULL;
246         }
247 }
248
249 static void
250 i915_gem_execbuffer_unreserve_vma(struct i915_vma *vma)
251 {
252         struct drm_i915_gem_exec_object2 *entry;
253
254         if (!drm_mm_node_allocated(&vma->node))
255                 return;
256
257         entry = vma->exec_entry;
258
259         if (entry->flags & __EXEC_OBJECT_HAS_FENCE)
260                 i915_vma_unpin_fence(vma);
261
262         if (entry->flags & __EXEC_OBJECT_HAS_PIN)
263                 __i915_vma_unpin(vma);
264
265         entry->flags &= ~(__EXEC_OBJECT_HAS_FENCE | __EXEC_OBJECT_HAS_PIN);
266 }
267
268 static void eb_destroy(struct eb_vmas *eb)
269 {
270         while (!list_empty(&eb->vmas)) {
271                 struct i915_vma *vma;
272
273                 vma = list_first_entry(&eb->vmas,
274                                        struct i915_vma,
275                                        exec_list);
276                 list_del_init(&vma->exec_list);
277                 i915_gem_execbuffer_unreserve_vma(vma);
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(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         cache->use_64bit_reloc = INTEL_GEN(cache->i915) >= 8;
336         cache->node.allocated = false;
337 }
338
339 static inline void *unmask_page(unsigned long p)
340 {
341         return (void *)(uintptr_t)(p & PAGE_MASK);
342 }
343
344 static inline unsigned int unmask_flags(unsigned long p)
345 {
346         return p & ~PAGE_MASK;
347 }
348
349 #define KMAP 0x4 /* after CLFLUSH_FLAGS */
350
351 static void reloc_cache_fini(struct reloc_cache *cache)
352 {
353         void *vaddr;
354
355         if (!cache->vaddr)
356                 return;
357
358         vaddr = unmask_page(cache->vaddr);
359         if (cache->vaddr & KMAP) {
360                 if (cache->vaddr & CLFLUSH_AFTER)
361                         mb();
362
363                 kunmap_atomic(vaddr);
364                 i915_gem_obj_finish_shmem_access((struct drm_i915_gem_object *)cache->node.mm);
365         } else {
366                 wmb();
367                 io_mapping_unmap_atomic((void __iomem *)vaddr);
368                 if (cache->node.allocated) {
369                         struct i915_ggtt *ggtt = &cache->i915->ggtt;
370
371                         ggtt->base.clear_range(&ggtt->base,
372                                                cache->node.start,
373                                                cache->node.size,
374                                                true);
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->node.allocated) {
423                 wmb();
424                 ggtt->base.insert_page(&ggtt->base,
425                                        i915_gem_object_get_dma_address(obj, page),
426                                        cache->node.start, I915_CACHE_NONE, 0);
427                 cache->page = page;
428                 return unmask_page(cache->vaddr);
429         }
430
431         if (cache->vaddr) {
432                 io_mapping_unmap_atomic(unmask_page(cache->vaddr));
433         } else {
434                 struct i915_vma *vma;
435                 int ret;
436
437                 if (use_cpu_reloc(obj))
438                         return NULL;
439
440                 ret = i915_gem_object_set_to_gtt_domain(obj, true);
441                 if (ret)
442                         return ERR_PTR(ret);
443
444                 vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
445                                                PIN_MAPPABLE | PIN_NONBLOCK);
446                 if (IS_ERR(vma)) {
447                         memset(&cache->node, 0, sizeof(cache->node));
448                         ret = drm_mm_insert_node_in_range_generic
449                                 (&ggtt->base.mm, &cache->node,
450                                  4096, 0, 0,
451                                  0, ggtt->mappable_end,
452                                  DRM_MM_SEARCH_DEFAULT,
453                                  DRM_MM_CREATE_DEFAULT);
454                         if (ret)
455                                 return ERR_PTR(ret);
456                 } else {
457                         ret = i915_vma_put_fence(vma);
458                         if (ret) {
459                                 i915_vma_unpin(vma);
460                                 return ERR_PTR(ret);
461                         }
462
463                         cache->node.start = vma->node.start;
464                         cache->node.mm = (void *)vma;
465                 }
466         }
467
468         offset = cache->node.start;
469         if (cache->node.allocated) {
470                 ggtt->base.insert_page(&ggtt->base,
471                                        i915_gem_object_get_dma_address(obj, page),
472                                        offset, I915_CACHE_NONE, 0);
473         } else {
474                 offset += page << PAGE_SHIFT;
475         }
476
477         vaddr = io_mapping_map_atomic_wc(cache->i915->ggtt.mappable, offset);
478         cache->page = page;
479         cache->vaddr = (unsigned long)vaddr;
480
481         return vaddr;
482 }
483
484 static void *reloc_vaddr(struct drm_i915_gem_object *obj,
485                          struct reloc_cache *cache,
486                          int page)
487 {
488         void *vaddr;
489
490         if (cache->page == page) {
491                 vaddr = unmask_page(cache->vaddr);
492         } else {
493                 vaddr = NULL;
494                 if ((cache->vaddr & KMAP) == 0)
495                         vaddr = reloc_iomap(obj, cache, page);
496                 if (!vaddr)
497                         vaddr = reloc_kmap(obj, cache, page);
498         }
499
500         return vaddr;
501 }
502
503 static void clflush_write32(u32 *addr, u32 value, unsigned int flushes)
504 {
505         if (unlikely(flushes & (CLFLUSH_BEFORE | CLFLUSH_AFTER))) {
506                 if (flushes & CLFLUSH_BEFORE) {
507                         clflushopt(addr);
508                         mb();
509                 }
510
511                 *addr = value;
512
513                 /* Writes to the same cacheline are serialised by the CPU
514                  * (including clflush). On the write path, we only require
515                  * that it hits memory in an orderly fashion and place
516                  * mb barriers at the start and end of the relocation phase
517                  * to ensure ordering of clflush wrt to the system.
518                  */
519                 if (flushes & CLFLUSH_AFTER)
520                         clflushopt(addr);
521         } else
522                 *addr = value;
523 }
524
525 static int
526 relocate_entry(struct drm_i915_gem_object *obj,
527                const struct drm_i915_gem_relocation_entry *reloc,
528                struct reloc_cache *cache,
529                u64 target_offset)
530 {
531         u64 offset = reloc->offset;
532         bool wide = cache->use_64bit_reloc;
533         void *vaddr;
534
535         target_offset = relocation_target(reloc, target_offset);
536 repeat:
537         vaddr = reloc_vaddr(obj, cache, offset >> PAGE_SHIFT);
538         if (IS_ERR(vaddr))
539                 return PTR_ERR(vaddr);
540
541         clflush_write32(vaddr + offset_in_page(offset),
542                         lower_32_bits(target_offset),
543                         cache->vaddr);
544
545         if (wide) {
546                 offset += sizeof(u32);
547                 target_offset >>= 32;
548                 wide = false;
549                 goto repeat;
550         }
551
552         return 0;
553 }
554
555 static bool object_is_idle(struct drm_i915_gem_object *obj)
556 {
557         unsigned long active = i915_gem_object_get_active(obj);
558         int idx;
559
560         for_each_active(active, idx) {
561                 if (!i915_gem_active_is_idle(&obj->last_read[idx],
562                                              &obj->base.dev->struct_mutex))
563                         return false;
564         }
565
566         return true;
567 }
568
569 static int
570 i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj,
571                                    struct eb_vmas *eb,
572                                    struct drm_i915_gem_relocation_entry *reloc,
573                                    struct reloc_cache *cache)
574 {
575         struct drm_device *dev = obj->base.dev;
576         struct drm_gem_object *target_obj;
577         struct drm_i915_gem_object *target_i915_obj;
578         struct i915_vma *target_vma;
579         uint64_t target_offset;
580         int ret;
581
582         /* we've already hold a reference to all valid objects */
583         target_vma = eb_get_vma(eb, reloc->target_handle);
584         if (unlikely(target_vma == NULL))
585                 return -ENOENT;
586         target_i915_obj = target_vma->obj;
587         target_obj = &target_vma->obj->base;
588
589         target_offset = gen8_canonical_addr(target_vma->node.start);
590
591         /* Sandybridge PPGTT errata: We need a global gtt mapping for MI and
592          * pipe_control writes because the gpu doesn't properly redirect them
593          * through the ppgtt for non_secure batchbuffers. */
594         if (unlikely(IS_GEN6(dev) &&
595             reloc->write_domain == I915_GEM_DOMAIN_INSTRUCTION)) {
596                 ret = i915_vma_bind(target_vma, target_i915_obj->cache_level,
597                                     PIN_GLOBAL);
598                 if (WARN_ONCE(ret, "Unexpected failure to bind target VMA!"))
599                         return ret;
600         }
601
602         /* Validate that the target is in a valid r/w GPU domain */
603         if (unlikely(reloc->write_domain & (reloc->write_domain - 1))) {
604                 DRM_DEBUG("reloc with multiple write domains: "
605                           "obj %p target %d offset %d "
606                           "read %08x write %08x",
607                           obj, reloc->target_handle,
608                           (int) reloc->offset,
609                           reloc->read_domains,
610                           reloc->write_domain);
611                 return -EINVAL;
612         }
613         if (unlikely((reloc->write_domain | reloc->read_domains)
614                      & ~I915_GEM_GPU_DOMAINS)) {
615                 DRM_DEBUG("reloc with read/write non-GPU domains: "
616                           "obj %p target %d offset %d "
617                           "read %08x write %08x",
618                           obj, reloc->target_handle,
619                           (int) reloc->offset,
620                           reloc->read_domains,
621                           reloc->write_domain);
622                 return -EINVAL;
623         }
624
625         target_obj->pending_read_domains |= reloc->read_domains;
626         target_obj->pending_write_domain |= reloc->write_domain;
627
628         /* If the relocation already has the right value in it, no
629          * more work needs to be done.
630          */
631         if (target_offset == reloc->presumed_offset)
632                 return 0;
633
634         /* Check that the relocation address is valid... */
635         if (unlikely(reloc->offset >
636                      obj->base.size - (cache->use_64bit_reloc ? 8 : 4))) {
637                 DRM_DEBUG("Relocation beyond object bounds: "
638                           "obj %p target %d offset %d size %d.\n",
639                           obj, reloc->target_handle,
640                           (int) reloc->offset,
641                           (int) obj->base.size);
642                 return -EINVAL;
643         }
644         if (unlikely(reloc->offset & 3)) {
645                 DRM_DEBUG("Relocation not 4-byte aligned: "
646                           "obj %p target %d offset %d.\n",
647                           obj, reloc->target_handle,
648                           (int) reloc->offset);
649                 return -EINVAL;
650         }
651
652         /* We can't wait for rendering with pagefaults disabled */
653         if (pagefault_disabled() && !object_is_idle(obj))
654                 return -EFAULT;
655
656         ret = relocate_entry(obj, reloc, cache, target_offset);
657         if (ret)
658                 return ret;
659
660         /* and update the user's relocation entry */
661         reloc->presumed_offset = target_offset;
662         return 0;
663 }
664
665 static int
666 i915_gem_execbuffer_relocate_vma(struct i915_vma *vma,
667                                  struct eb_vmas *eb)
668 {
669 #define N_RELOC(x) ((x) / sizeof(struct drm_i915_gem_relocation_entry))
670         struct drm_i915_gem_relocation_entry stack_reloc[N_RELOC(512)];
671         struct drm_i915_gem_relocation_entry __user *user_relocs;
672         struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
673         struct reloc_cache cache;
674         int remain, ret = 0;
675
676         user_relocs = u64_to_user_ptr(entry->relocs_ptr);
677         reloc_cache_init(&cache, eb->i915);
678
679         remain = entry->relocation_count;
680         while (remain) {
681                 struct drm_i915_gem_relocation_entry *r = stack_reloc;
682                 int count = remain;
683                 if (count > ARRAY_SIZE(stack_reloc))
684                         count = ARRAY_SIZE(stack_reloc);
685                 remain -= count;
686
687                 if (__copy_from_user_inatomic(r, user_relocs, count*sizeof(r[0]))) {
688                         ret = -EFAULT;
689                         goto out;
690                 }
691
692                 do {
693                         u64 offset = r->presumed_offset;
694
695                         ret = i915_gem_execbuffer_relocate_entry(vma->obj, eb, r, &cache);
696                         if (ret)
697                                 goto out;
698
699                         if (r->presumed_offset != offset &&
700                             __put_user(r->presumed_offset,
701                                        &user_relocs->presumed_offset)) {
702                                 ret = -EFAULT;
703                                 goto out;
704                         }
705
706                         user_relocs++;
707                         r++;
708                 } while (--count);
709         }
710
711 out:
712         reloc_cache_fini(&cache);
713         return ret;
714 #undef N_RELOC
715 }
716
717 static int
718 i915_gem_execbuffer_relocate_vma_slow(struct i915_vma *vma,
719                                       struct eb_vmas *eb,
720                                       struct drm_i915_gem_relocation_entry *relocs)
721 {
722         const struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
723         struct reloc_cache cache;
724         int i, ret = 0;
725
726         reloc_cache_init(&cache, eb->i915);
727         for (i = 0; i < entry->relocation_count; i++) {
728                 ret = i915_gem_execbuffer_relocate_entry(vma->obj, eb, &relocs[i], &cache);
729                 if (ret)
730                         break;
731         }
732         reloc_cache_fini(&cache);
733
734         return ret;
735 }
736
737 static int
738 i915_gem_execbuffer_relocate(struct eb_vmas *eb)
739 {
740         struct i915_vma *vma;
741         int ret = 0;
742
743         /* This is the fast path and we cannot handle a pagefault whilst
744          * holding the struct mutex lest the user pass in the relocations
745          * contained within a mmaped bo. For in such a case we, the page
746          * fault handler would call i915_gem_fault() and we would try to
747          * acquire the struct mutex again. Obviously this is bad and so
748          * lockdep complains vehemently.
749          */
750         pagefault_disable();
751         list_for_each_entry(vma, &eb->vmas, exec_list) {
752                 ret = i915_gem_execbuffer_relocate_vma(vma, eb);
753                 if (ret)
754                         break;
755         }
756         pagefault_enable();
757
758         return ret;
759 }
760
761 static bool only_mappable_for_reloc(unsigned int flags)
762 {
763         return (flags & (EXEC_OBJECT_NEEDS_FENCE | __EXEC_OBJECT_NEEDS_MAP)) ==
764                 __EXEC_OBJECT_NEEDS_MAP;
765 }
766
767 static int
768 i915_gem_execbuffer_reserve_vma(struct i915_vma *vma,
769                                 struct intel_engine_cs *engine,
770                                 bool *need_reloc)
771 {
772         struct drm_i915_gem_object *obj = vma->obj;
773         struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
774         uint64_t flags;
775         int ret;
776
777         flags = PIN_USER;
778         if (entry->flags & EXEC_OBJECT_NEEDS_GTT)
779                 flags |= PIN_GLOBAL;
780
781         if (!drm_mm_node_allocated(&vma->node)) {
782                 /* Wa32bitGeneralStateOffset & Wa32bitInstructionBaseOffset,
783                  * limit address to the first 4GBs for unflagged objects.
784                  */
785                 if ((entry->flags & EXEC_OBJECT_SUPPORTS_48B_ADDRESS) == 0)
786                         flags |= PIN_ZONE_4G;
787                 if (entry->flags & __EXEC_OBJECT_NEEDS_MAP)
788                         flags |= PIN_GLOBAL | PIN_MAPPABLE;
789                 if (entry->flags & __EXEC_OBJECT_NEEDS_BIAS)
790                         flags |= BATCH_OFFSET_BIAS | PIN_OFFSET_BIAS;
791                 if (entry->flags & EXEC_OBJECT_PINNED)
792                         flags |= entry->offset | PIN_OFFSET_FIXED;
793                 if ((flags & PIN_MAPPABLE) == 0)
794                         flags |= PIN_HIGH;
795         }
796
797         ret = i915_vma_pin(vma,
798                            entry->pad_to_size,
799                            entry->alignment,
800                            flags);
801         if ((ret == -ENOSPC || ret == -E2BIG) &&
802             only_mappable_for_reloc(entry->flags))
803                 ret = i915_vma_pin(vma,
804                                    entry->pad_to_size,
805                                    entry->alignment,
806                                    flags & ~PIN_MAPPABLE);
807         if (ret)
808                 return ret;
809
810         entry->flags |= __EXEC_OBJECT_HAS_PIN;
811
812         if (entry->flags & EXEC_OBJECT_NEEDS_FENCE) {
813                 ret = i915_vma_get_fence(vma);
814                 if (ret)
815                         return ret;
816
817                 if (i915_vma_pin_fence(vma))
818                         entry->flags |= __EXEC_OBJECT_HAS_FENCE;
819         }
820
821         if (entry->offset != vma->node.start) {
822                 entry->offset = vma->node.start;
823                 *need_reloc = true;
824         }
825
826         if (entry->flags & EXEC_OBJECT_WRITE) {
827                 obj->base.pending_read_domains = I915_GEM_DOMAIN_RENDER;
828                 obj->base.pending_write_domain = I915_GEM_DOMAIN_RENDER;
829         }
830
831         return 0;
832 }
833
834 static bool
835 need_reloc_mappable(struct i915_vma *vma)
836 {
837         struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
838
839         if (entry->relocation_count == 0)
840                 return false;
841
842         if (!i915_vma_is_ggtt(vma))
843                 return false;
844
845         /* See also use_cpu_reloc() */
846         if (HAS_LLC(vma->obj->base.dev))
847                 return false;
848
849         if (vma->obj->base.write_domain == I915_GEM_DOMAIN_CPU)
850                 return false;
851
852         return true;
853 }
854
855 static bool
856 eb_vma_misplaced(struct i915_vma *vma)
857 {
858         struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
859
860         WARN_ON(entry->flags & __EXEC_OBJECT_NEEDS_MAP &&
861                 !i915_vma_is_ggtt(vma));
862
863         if (entry->alignment &&
864             vma->node.start & (entry->alignment - 1))
865                 return true;
866
867         if (vma->node.size < entry->pad_to_size)
868                 return true;
869
870         if (entry->flags & EXEC_OBJECT_PINNED &&
871             vma->node.start != entry->offset)
872                 return true;
873
874         if (entry->flags & __EXEC_OBJECT_NEEDS_BIAS &&
875             vma->node.start < BATCH_OFFSET_BIAS)
876                 return true;
877
878         /* avoid costly ping-pong once a batch bo ended up non-mappable */
879         if (entry->flags & __EXEC_OBJECT_NEEDS_MAP &&
880             !i915_vma_is_map_and_fenceable(vma))
881                 return !only_mappable_for_reloc(entry->flags);
882
883         if ((entry->flags & EXEC_OBJECT_SUPPORTS_48B_ADDRESS) == 0 &&
884             (vma->node.start + vma->node.size - 1) >> 32)
885                 return true;
886
887         return false;
888 }
889
890 static int
891 i915_gem_execbuffer_reserve(struct intel_engine_cs *engine,
892                             struct list_head *vmas,
893                             struct i915_gem_context *ctx,
894                             bool *need_relocs)
895 {
896         struct drm_i915_gem_object *obj;
897         struct i915_vma *vma;
898         struct i915_address_space *vm;
899         struct list_head ordered_vmas;
900         struct list_head pinned_vmas;
901         bool has_fenced_gpu_access = INTEL_GEN(engine->i915) < 4;
902         int retry;
903
904         vm = list_first_entry(vmas, struct i915_vma, exec_list)->vm;
905
906         INIT_LIST_HEAD(&ordered_vmas);
907         INIT_LIST_HEAD(&pinned_vmas);
908         while (!list_empty(vmas)) {
909                 struct drm_i915_gem_exec_object2 *entry;
910                 bool need_fence, need_mappable;
911
912                 vma = list_first_entry(vmas, struct i915_vma, exec_list);
913                 obj = vma->obj;
914                 entry = vma->exec_entry;
915
916                 if (ctx->flags & CONTEXT_NO_ZEROMAP)
917                         entry->flags |= __EXEC_OBJECT_NEEDS_BIAS;
918
919                 if (!has_fenced_gpu_access)
920                         entry->flags &= ~EXEC_OBJECT_NEEDS_FENCE;
921                 need_fence =
922                         entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
923                         i915_gem_object_is_tiled(obj);
924                 need_mappable = need_fence || need_reloc_mappable(vma);
925
926                 if (entry->flags & EXEC_OBJECT_PINNED)
927                         list_move_tail(&vma->exec_list, &pinned_vmas);
928                 else if (need_mappable) {
929                         entry->flags |= __EXEC_OBJECT_NEEDS_MAP;
930                         list_move(&vma->exec_list, &ordered_vmas);
931                 } else
932                         list_move_tail(&vma->exec_list, &ordered_vmas);
933
934                 obj->base.pending_read_domains = I915_GEM_GPU_DOMAINS & ~I915_GEM_DOMAIN_COMMAND;
935                 obj->base.pending_write_domain = 0;
936         }
937         list_splice(&ordered_vmas, vmas);
938         list_splice(&pinned_vmas, vmas);
939
940         /* Attempt to pin all of the buffers into the GTT.
941          * This is done in 3 phases:
942          *
943          * 1a. Unbind all objects that do not match the GTT constraints for
944          *     the execbuffer (fenceable, mappable, alignment etc).
945          * 1b. Increment pin count for already bound objects.
946          * 2.  Bind new objects.
947          * 3.  Decrement pin count.
948          *
949          * This avoid unnecessary unbinding of later objects in order to make
950          * room for the earlier objects *unless* we need to defragment.
951          */
952         retry = 0;
953         do {
954                 int ret = 0;
955
956                 /* Unbind any ill-fitting objects or pin. */
957                 list_for_each_entry(vma, vmas, exec_list) {
958                         if (!drm_mm_node_allocated(&vma->node))
959                                 continue;
960
961                         if (eb_vma_misplaced(vma))
962                                 ret = i915_vma_unbind(vma);
963                         else
964                                 ret = i915_gem_execbuffer_reserve_vma(vma,
965                                                                       engine,
966                                                                       need_relocs);
967                         if (ret)
968                                 goto err;
969                 }
970
971                 /* Bind fresh objects */
972                 list_for_each_entry(vma, vmas, exec_list) {
973                         if (drm_mm_node_allocated(&vma->node))
974                                 continue;
975
976                         ret = i915_gem_execbuffer_reserve_vma(vma, engine,
977                                                               need_relocs);
978                         if (ret)
979                                 goto err;
980                 }
981
982 err:
983                 if (ret != -ENOSPC || retry++)
984                         return ret;
985
986                 /* Decrement pin count for bound objects */
987                 list_for_each_entry(vma, vmas, exec_list)
988                         i915_gem_execbuffer_unreserve_vma(vma);
989
990                 ret = i915_gem_evict_vm(vm, true);
991                 if (ret)
992                         return ret;
993         } while (1);
994 }
995
996 static int
997 i915_gem_execbuffer_relocate_slow(struct drm_device *dev,
998                                   struct drm_i915_gem_execbuffer2 *args,
999                                   struct drm_file *file,
1000                                   struct intel_engine_cs *engine,
1001                                   struct eb_vmas *eb,
1002                                   struct drm_i915_gem_exec_object2 *exec,
1003                                   struct i915_gem_context *ctx)
1004 {
1005         struct drm_i915_gem_relocation_entry *reloc;
1006         struct i915_address_space *vm;
1007         struct i915_vma *vma;
1008         bool need_relocs;
1009         int *reloc_offset;
1010         int i, total, ret;
1011         unsigned count = args->buffer_count;
1012
1013         vm = list_first_entry(&eb->vmas, struct i915_vma, exec_list)->vm;
1014
1015         /* We may process another execbuffer during the unlock... */
1016         while (!list_empty(&eb->vmas)) {
1017                 vma = list_first_entry(&eb->vmas, struct i915_vma, exec_list);
1018                 list_del_init(&vma->exec_list);
1019                 i915_gem_execbuffer_unreserve_vma(vma);
1020                 i915_vma_put(vma);
1021         }
1022
1023         mutex_unlock(&dev->struct_mutex);
1024
1025         total = 0;
1026         for (i = 0; i < count; i++)
1027                 total += exec[i].relocation_count;
1028
1029         reloc_offset = drm_malloc_ab(count, sizeof(*reloc_offset));
1030         reloc = drm_malloc_ab(total, sizeof(*reloc));
1031         if (reloc == NULL || reloc_offset == NULL) {
1032                 drm_free_large(reloc);
1033                 drm_free_large(reloc_offset);
1034                 mutex_lock(&dev->struct_mutex);
1035                 return -ENOMEM;
1036         }
1037
1038         total = 0;
1039         for (i = 0; i < count; i++) {
1040                 struct drm_i915_gem_relocation_entry __user *user_relocs;
1041                 u64 invalid_offset = (u64)-1;
1042                 int j;
1043
1044                 user_relocs = u64_to_user_ptr(exec[i].relocs_ptr);
1045
1046                 if (copy_from_user(reloc+total, user_relocs,
1047                                    exec[i].relocation_count * sizeof(*reloc))) {
1048                         ret = -EFAULT;
1049                         mutex_lock(&dev->struct_mutex);
1050                         goto err;
1051                 }
1052
1053                 /* As we do not update the known relocation offsets after
1054                  * relocating (due to the complexities in lock handling),
1055                  * we need to mark them as invalid now so that we force the
1056                  * relocation processing next time. Just in case the target
1057                  * object is evicted and then rebound into its old
1058                  * presumed_offset before the next execbuffer - if that
1059                  * happened we would make the mistake of assuming that the
1060                  * relocations were valid.
1061                  */
1062                 for (j = 0; j < exec[i].relocation_count; j++) {
1063                         if (__copy_to_user(&user_relocs[j].presumed_offset,
1064                                            &invalid_offset,
1065                                            sizeof(invalid_offset))) {
1066                                 ret = -EFAULT;
1067                                 mutex_lock(&dev->struct_mutex);
1068                                 goto err;
1069                         }
1070                 }
1071
1072                 reloc_offset[i] = total;
1073                 total += exec[i].relocation_count;
1074         }
1075
1076         ret = i915_mutex_lock_interruptible(dev);
1077         if (ret) {
1078                 mutex_lock(&dev->struct_mutex);
1079                 goto err;
1080         }
1081
1082         /* reacquire the objects */
1083         eb_reset(eb);
1084         ret = eb_lookup_vmas(eb, exec, args, vm, file);
1085         if (ret)
1086                 goto err;
1087
1088         need_relocs = (args->flags & I915_EXEC_NO_RELOC) == 0;
1089         ret = i915_gem_execbuffer_reserve(engine, &eb->vmas, ctx,
1090                                           &need_relocs);
1091         if (ret)
1092                 goto err;
1093
1094         list_for_each_entry(vma, &eb->vmas, exec_list) {
1095                 int offset = vma->exec_entry - exec;
1096                 ret = i915_gem_execbuffer_relocate_vma_slow(vma, eb,
1097                                                             reloc + reloc_offset[offset]);
1098                 if (ret)
1099                         goto err;
1100         }
1101
1102         /* Leave the user relocations as are, this is the painfully slow path,
1103          * and we want to avoid the complication of dropping the lock whilst
1104          * having buffers reserved in the aperture and so causing spurious
1105          * ENOSPC for random operations.
1106          */
1107
1108 err:
1109         drm_free_large(reloc);
1110         drm_free_large(reloc_offset);
1111         return ret;
1112 }
1113
1114 static unsigned int eb_other_engines(struct drm_i915_gem_request *req)
1115 {
1116         unsigned int mask;
1117
1118         mask = ~intel_engine_flag(req->engine) & I915_BO_ACTIVE_MASK;
1119         mask <<= I915_BO_ACTIVE_SHIFT;
1120
1121         return mask;
1122 }
1123
1124 static int
1125 i915_gem_execbuffer_move_to_gpu(struct drm_i915_gem_request *req,
1126                                 struct list_head *vmas)
1127 {
1128         const unsigned int other_rings = eb_other_engines(req);
1129         struct i915_vma *vma;
1130         int ret;
1131
1132         list_for_each_entry(vma, vmas, exec_list) {
1133                 struct drm_i915_gem_object *obj = vma->obj;
1134
1135                 if (obj->flags & other_rings) {
1136                         ret = i915_gem_object_sync(obj, req);
1137                         if (ret)
1138                                 return ret;
1139                 }
1140
1141                 if (obj->base.write_domain & I915_GEM_DOMAIN_CPU)
1142                         i915_gem_clflush_object(obj, false);
1143         }
1144
1145         /* Unconditionally flush any chipset caches (for streaming writes). */
1146         i915_gem_chipset_flush(req->engine->i915);
1147
1148         /* Unconditionally invalidate GPU caches and TLBs. */
1149         return req->engine->emit_flush(req, EMIT_INVALIDATE);
1150 }
1151
1152 static bool
1153 i915_gem_check_execbuffer(struct drm_i915_gem_execbuffer2 *exec)
1154 {
1155         if (exec->flags & __I915_EXEC_UNKNOWN_FLAGS)
1156                 return false;
1157
1158         /* Kernel clipping was a DRI1 misfeature */
1159         if (exec->num_cliprects || exec->cliprects_ptr)
1160                 return false;
1161
1162         if (exec->DR4 == 0xffffffff) {
1163                 DRM_DEBUG("UXA submitting garbage DR4, fixing up\n");
1164                 exec->DR4 = 0;
1165         }
1166         if (exec->DR1 || exec->DR4)
1167                 return false;
1168
1169         if ((exec->batch_start_offset | exec->batch_len) & 0x7)
1170                 return false;
1171
1172         return true;
1173 }
1174
1175 static int
1176 validate_exec_list(struct drm_device *dev,
1177                    struct drm_i915_gem_exec_object2 *exec,
1178                    int count)
1179 {
1180         unsigned relocs_total = 0;
1181         unsigned relocs_max = UINT_MAX / sizeof(struct drm_i915_gem_relocation_entry);
1182         unsigned invalid_flags;
1183         int i;
1184
1185         /* INTERNAL flags must not overlap with external ones */
1186         BUILD_BUG_ON(__EXEC_OBJECT_INTERNAL_FLAGS & ~__EXEC_OBJECT_UNKNOWN_FLAGS);
1187
1188         invalid_flags = __EXEC_OBJECT_UNKNOWN_FLAGS;
1189         if (USES_FULL_PPGTT(dev))
1190                 invalid_flags |= EXEC_OBJECT_NEEDS_GTT;
1191
1192         for (i = 0; i < count; i++) {
1193                 char __user *ptr = u64_to_user_ptr(exec[i].relocs_ptr);
1194                 int length; /* limited by fault_in_pages_readable() */
1195
1196                 if (exec[i].flags & invalid_flags)
1197                         return -EINVAL;
1198
1199                 /* Offset can be used as input (EXEC_OBJECT_PINNED), reject
1200                  * any non-page-aligned or non-canonical addresses.
1201                  */
1202                 if (exec[i].flags & EXEC_OBJECT_PINNED) {
1203                         if (exec[i].offset !=
1204                             gen8_canonical_addr(exec[i].offset & PAGE_MASK))
1205                                 return -EINVAL;
1206
1207                         /* From drm_mm perspective address space is continuous,
1208                          * so from this point we're always using non-canonical
1209                          * form internally.
1210                          */
1211                         exec[i].offset = gen8_noncanonical_addr(exec[i].offset);
1212                 }
1213
1214                 if (exec[i].alignment && !is_power_of_2(exec[i].alignment))
1215                         return -EINVAL;
1216
1217                 /* pad_to_size was once a reserved field, so sanitize it */
1218                 if (exec[i].flags & EXEC_OBJECT_PAD_TO_SIZE) {
1219                         if (offset_in_page(exec[i].pad_to_size))
1220                                 return -EINVAL;
1221                 } else {
1222                         exec[i].pad_to_size = 0;
1223                 }
1224
1225                 /* First check for malicious input causing overflow in
1226                  * the worst case where we need to allocate the entire
1227                  * relocation tree as a single array.
1228                  */
1229                 if (exec[i].relocation_count > relocs_max - relocs_total)
1230                         return -EINVAL;
1231                 relocs_total += exec[i].relocation_count;
1232
1233                 length = exec[i].relocation_count *
1234                         sizeof(struct drm_i915_gem_relocation_entry);
1235                 /*
1236                  * We must check that the entire relocation array is safe
1237                  * to read, but since we may need to update the presumed
1238                  * offsets during execution, check for full write access.
1239                  */
1240                 if (!access_ok(VERIFY_WRITE, ptr, length))
1241                         return -EFAULT;
1242
1243                 if (likely(!i915.prefault_disable)) {
1244                         if (fault_in_multipages_readable(ptr, length))
1245                                 return -EFAULT;
1246                 }
1247         }
1248
1249         return 0;
1250 }
1251
1252 static struct i915_gem_context *
1253 i915_gem_validate_context(struct drm_device *dev, struct drm_file *file,
1254                           struct intel_engine_cs *engine, const u32 ctx_id)
1255 {
1256         struct i915_gem_context *ctx = NULL;
1257         struct i915_ctx_hang_stats *hs;
1258
1259         if (engine->id != RCS && ctx_id != DEFAULT_CONTEXT_HANDLE)
1260                 return ERR_PTR(-EINVAL);
1261
1262         ctx = i915_gem_context_lookup(file->driver_priv, ctx_id);
1263         if (IS_ERR(ctx))
1264                 return ctx;
1265
1266         hs = &ctx->hang_stats;
1267         if (hs->banned) {
1268                 DRM_DEBUG("Context %u tried to submit while banned\n", ctx_id);
1269                 return ERR_PTR(-EIO);
1270         }
1271
1272         return ctx;
1273 }
1274
1275 void i915_vma_move_to_active(struct i915_vma *vma,
1276                              struct drm_i915_gem_request *req,
1277                              unsigned int flags)
1278 {
1279         struct drm_i915_gem_object *obj = vma->obj;
1280         const unsigned int idx = req->engine->id;
1281
1282         GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
1283
1284         obj->dirty = 1; /* be paranoid  */
1285
1286         /* Add a reference if we're newly entering the active list.
1287          * The order in which we add operations to the retirement queue is
1288          * vital here: mark_active adds to the start of the callback list,
1289          * such that subsequent callbacks are called first. Therefore we
1290          * add the active reference first and queue for it to be dropped
1291          * *last*.
1292          */
1293         if (!i915_gem_object_is_active(obj))
1294                 i915_gem_object_get(obj);
1295         i915_gem_object_set_active(obj, idx);
1296         i915_gem_active_set(&obj->last_read[idx], req);
1297
1298         if (flags & EXEC_OBJECT_WRITE) {
1299                 i915_gem_active_set(&obj->last_write, req);
1300
1301                 intel_fb_obj_invalidate(obj, ORIGIN_CS);
1302
1303                 /* update for the implicit flush after a batch */
1304                 obj->base.write_domain &= ~I915_GEM_GPU_DOMAINS;
1305         }
1306
1307         if (flags & EXEC_OBJECT_NEEDS_FENCE)
1308                 i915_gem_active_set(&vma->last_fence, req);
1309
1310         i915_vma_set_active(vma, idx);
1311         i915_gem_active_set(&vma->last_read[idx], req);
1312         list_move_tail(&vma->vm_link, &vma->vm->active_list);
1313 }
1314
1315 static void eb_export_fence(struct drm_i915_gem_object *obj,
1316                             struct drm_i915_gem_request *req,
1317                             unsigned int flags)
1318 {
1319         struct reservation_object *resv;
1320
1321         resv = i915_gem_object_get_dmabuf_resv(obj);
1322         if (!resv)
1323                 return;
1324
1325         /* Ignore errors from failing to allocate the new fence, we can't
1326          * handle an error right now. Worst case should be missed
1327          * synchronisation leading to rendering corruption.
1328          */
1329         ww_mutex_lock(&resv->lock, NULL);
1330         if (flags & EXEC_OBJECT_WRITE)
1331                 reservation_object_add_excl_fence(resv, &req->fence);
1332         else if (reservation_object_reserve_shared(resv) == 0)
1333                 reservation_object_add_shared_fence(resv, &req->fence);
1334         ww_mutex_unlock(&resv->lock);
1335 }
1336
1337 static void
1338 i915_gem_execbuffer_move_to_active(struct list_head *vmas,
1339                                    struct drm_i915_gem_request *req)
1340 {
1341         struct i915_vma *vma;
1342
1343         list_for_each_entry(vma, vmas, exec_list) {
1344                 struct drm_i915_gem_object *obj = vma->obj;
1345                 u32 old_read = obj->base.read_domains;
1346                 u32 old_write = obj->base.write_domain;
1347
1348                 obj->base.write_domain = obj->base.pending_write_domain;
1349                 if (obj->base.write_domain)
1350                         vma->exec_entry->flags |= EXEC_OBJECT_WRITE;
1351                 else
1352                         obj->base.pending_read_domains |= obj->base.read_domains;
1353                 obj->base.read_domains = obj->base.pending_read_domains;
1354
1355                 i915_vma_move_to_active(vma, req, vma->exec_entry->flags);
1356                 eb_export_fence(obj, req, vma->exec_entry->flags);
1357                 trace_i915_gem_object_change_domain(obj, old_read, old_write);
1358         }
1359 }
1360
1361 static int
1362 i915_reset_gen7_sol_offsets(struct drm_i915_gem_request *req)
1363 {
1364         struct intel_ring *ring = req->ring;
1365         int ret, i;
1366
1367         if (!IS_GEN7(req->i915) || req->engine->id != RCS) {
1368                 DRM_DEBUG("sol reset is gen7/rcs only\n");
1369                 return -EINVAL;
1370         }
1371
1372         ret = intel_ring_begin(req, 4 * 3);
1373         if (ret)
1374                 return ret;
1375
1376         for (i = 0; i < 4; i++) {
1377                 intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
1378                 intel_ring_emit_reg(ring, GEN7_SO_WRITE_OFFSET(i));
1379                 intel_ring_emit(ring, 0);
1380         }
1381
1382         intel_ring_advance(ring);
1383
1384         return 0;
1385 }
1386
1387 static struct i915_vma *
1388 i915_gem_execbuffer_parse(struct intel_engine_cs *engine,
1389                           struct drm_i915_gem_exec_object2 *shadow_exec_entry,
1390                           struct drm_i915_gem_object *batch_obj,
1391                           struct eb_vmas *eb,
1392                           u32 batch_start_offset,
1393                           u32 batch_len,
1394                           bool is_master)
1395 {
1396         struct drm_i915_gem_object *shadow_batch_obj;
1397         struct i915_vma *vma;
1398         int ret;
1399
1400         shadow_batch_obj = i915_gem_batch_pool_get(&engine->batch_pool,
1401                                                    PAGE_ALIGN(batch_len));
1402         if (IS_ERR(shadow_batch_obj))
1403                 return ERR_CAST(shadow_batch_obj);
1404
1405         ret = intel_engine_cmd_parser(engine,
1406                                       batch_obj,
1407                                       shadow_batch_obj,
1408                                       batch_start_offset,
1409                                       batch_len,
1410                                       is_master);
1411         if (ret) {
1412                 if (ret == -EACCES) /* unhandled chained batch */
1413                         vma = NULL;
1414                 else
1415                         vma = ERR_PTR(ret);
1416                 goto out;
1417         }
1418
1419         vma = i915_gem_object_ggtt_pin(shadow_batch_obj, NULL, 0, 0, 0);
1420         if (IS_ERR(vma))
1421                 goto out;
1422
1423         memset(shadow_exec_entry, 0, sizeof(*shadow_exec_entry));
1424
1425         vma->exec_entry = shadow_exec_entry;
1426         vma->exec_entry->flags = __EXEC_OBJECT_HAS_PIN;
1427         i915_gem_object_get(shadow_batch_obj);
1428         list_add_tail(&vma->exec_list, &eb->vmas);
1429
1430 out:
1431         i915_gem_object_unpin_pages(shadow_batch_obj);
1432         return vma;
1433 }
1434
1435 static int
1436 execbuf_submit(struct i915_execbuffer_params *params,
1437                struct drm_i915_gem_execbuffer2 *args,
1438                struct list_head *vmas)
1439 {
1440         struct drm_i915_private *dev_priv = params->request->i915;
1441         u64 exec_start, exec_len;
1442         int instp_mode;
1443         u32 instp_mask;
1444         int ret;
1445
1446         ret = i915_gem_execbuffer_move_to_gpu(params->request, vmas);
1447         if (ret)
1448                 return ret;
1449
1450         ret = i915_switch_context(params->request);
1451         if (ret)
1452                 return ret;
1453
1454         instp_mode = args->flags & I915_EXEC_CONSTANTS_MASK;
1455         instp_mask = I915_EXEC_CONSTANTS_MASK;
1456         switch (instp_mode) {
1457         case I915_EXEC_CONSTANTS_REL_GENERAL:
1458         case I915_EXEC_CONSTANTS_ABSOLUTE:
1459         case I915_EXEC_CONSTANTS_REL_SURFACE:
1460                 if (instp_mode != 0 && params->engine->id != RCS) {
1461                         DRM_DEBUG("non-0 rel constants mode on non-RCS\n");
1462                         return -EINVAL;
1463                 }
1464
1465                 if (instp_mode != dev_priv->relative_constants_mode) {
1466                         if (INTEL_INFO(dev_priv)->gen < 4) {
1467                                 DRM_DEBUG("no rel constants on pre-gen4\n");
1468                                 return -EINVAL;
1469                         }
1470
1471                         if (INTEL_INFO(dev_priv)->gen > 5 &&
1472                             instp_mode == I915_EXEC_CONSTANTS_REL_SURFACE) {
1473                                 DRM_DEBUG("rel surface constants mode invalid on gen5+\n");
1474                                 return -EINVAL;
1475                         }
1476
1477                         /* The HW changed the meaning on this bit on gen6 */
1478                         if (INTEL_INFO(dev_priv)->gen >= 6)
1479                                 instp_mask &= ~I915_EXEC_CONSTANTS_REL_SURFACE;
1480                 }
1481                 break;
1482         default:
1483                 DRM_DEBUG("execbuf with unknown constants: %d\n", instp_mode);
1484                 return -EINVAL;
1485         }
1486
1487         if (params->engine->id == RCS &&
1488             instp_mode != dev_priv->relative_constants_mode) {
1489                 struct intel_ring *ring = params->request->ring;
1490
1491                 ret = intel_ring_begin(params->request, 4);
1492                 if (ret)
1493                         return ret;
1494
1495                 intel_ring_emit(ring, MI_NOOP);
1496                 intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
1497                 intel_ring_emit_reg(ring, INSTPM);
1498                 intel_ring_emit(ring, instp_mask << 16 | instp_mode);
1499                 intel_ring_advance(ring);
1500
1501                 dev_priv->relative_constants_mode = instp_mode;
1502         }
1503
1504         if (args->flags & I915_EXEC_GEN7_SOL_RESET) {
1505                 ret = i915_reset_gen7_sol_offsets(params->request);
1506                 if (ret)
1507                         return ret;
1508         }
1509
1510         exec_len   = args->batch_len;
1511         exec_start = params->batch->node.start +
1512                      params->args_batch_start_offset;
1513
1514         if (exec_len == 0)
1515                 exec_len = params->batch->size - params->args_batch_start_offset;
1516
1517         ret = params->engine->emit_bb_start(params->request,
1518                                             exec_start, exec_len,
1519                                             params->dispatch_flags);
1520         if (ret)
1521                 return ret;
1522
1523         trace_i915_gem_ring_dispatch(params->request, params->dispatch_flags);
1524
1525         i915_gem_execbuffer_move_to_active(vmas, params->request);
1526
1527         return 0;
1528 }
1529
1530 /**
1531  * Find one BSD ring to dispatch the corresponding BSD command.
1532  * The engine index is returned.
1533  */
1534 static unsigned int
1535 gen8_dispatch_bsd_engine(struct drm_i915_private *dev_priv,
1536                          struct drm_file *file)
1537 {
1538         struct drm_i915_file_private *file_priv = file->driver_priv;
1539
1540         /* Check whether the file_priv has already selected one ring. */
1541         if ((int)file_priv->bsd_engine < 0) {
1542                 /* If not, use the ping-pong mechanism to select one. */
1543                 mutex_lock(&dev_priv->drm.struct_mutex);
1544                 file_priv->bsd_engine = dev_priv->mm.bsd_engine_dispatch_index;
1545                 dev_priv->mm.bsd_engine_dispatch_index ^= 1;
1546                 mutex_unlock(&dev_priv->drm.struct_mutex);
1547         }
1548
1549         return file_priv->bsd_engine;
1550 }
1551
1552 #define I915_USER_RINGS (4)
1553
1554 static const enum intel_engine_id user_ring_map[I915_USER_RINGS + 1] = {
1555         [I915_EXEC_DEFAULT]     = RCS,
1556         [I915_EXEC_RENDER]      = RCS,
1557         [I915_EXEC_BLT]         = BCS,
1558         [I915_EXEC_BSD]         = VCS,
1559         [I915_EXEC_VEBOX]       = VECS
1560 };
1561
1562 static struct intel_engine_cs *
1563 eb_select_engine(struct drm_i915_private *dev_priv,
1564                  struct drm_file *file,
1565                  struct drm_i915_gem_execbuffer2 *args)
1566 {
1567         unsigned int user_ring_id = args->flags & I915_EXEC_RING_MASK;
1568         struct intel_engine_cs *engine;
1569
1570         if (user_ring_id > I915_USER_RINGS) {
1571                 DRM_DEBUG("execbuf with unknown ring: %u\n", user_ring_id);
1572                 return NULL;
1573         }
1574
1575         if ((user_ring_id != I915_EXEC_BSD) &&
1576             ((args->flags & I915_EXEC_BSD_MASK) != 0)) {
1577                 DRM_DEBUG("execbuf with non bsd ring but with invalid "
1578                           "bsd dispatch flags: %d\n", (int)(args->flags));
1579                 return NULL;
1580         }
1581
1582         if (user_ring_id == I915_EXEC_BSD && HAS_BSD2(dev_priv)) {
1583                 unsigned int bsd_idx = args->flags & I915_EXEC_BSD_MASK;
1584
1585                 if (bsd_idx == I915_EXEC_BSD_DEFAULT) {
1586                         bsd_idx = gen8_dispatch_bsd_engine(dev_priv, file);
1587                 } else if (bsd_idx >= I915_EXEC_BSD_RING1 &&
1588                            bsd_idx <= I915_EXEC_BSD_RING2) {
1589                         bsd_idx >>= I915_EXEC_BSD_SHIFT;
1590                         bsd_idx--;
1591                 } else {
1592                         DRM_DEBUG("execbuf with unknown bsd ring: %u\n",
1593                                   bsd_idx);
1594                         return NULL;
1595                 }
1596
1597                 engine = &dev_priv->engine[_VCS(bsd_idx)];
1598         } else {
1599                 engine = &dev_priv->engine[user_ring_map[user_ring_id]];
1600         }
1601
1602         if (!intel_engine_initialized(engine)) {
1603                 DRM_DEBUG("execbuf with invalid ring: %u\n", user_ring_id);
1604                 return NULL;
1605         }
1606
1607         return engine;
1608 }
1609
1610 static int
1611 i915_gem_do_execbuffer(struct drm_device *dev, void *data,
1612                        struct drm_file *file,
1613                        struct drm_i915_gem_execbuffer2 *args,
1614                        struct drm_i915_gem_exec_object2 *exec)
1615 {
1616         struct drm_i915_private *dev_priv = to_i915(dev);
1617         struct i915_ggtt *ggtt = &dev_priv->ggtt;
1618         struct eb_vmas *eb;
1619         struct drm_i915_gem_exec_object2 shadow_exec_entry;
1620         struct intel_engine_cs *engine;
1621         struct i915_gem_context *ctx;
1622         struct i915_address_space *vm;
1623         struct i915_execbuffer_params params_master; /* XXX: will be removed later */
1624         struct i915_execbuffer_params *params = &params_master;
1625         const u32 ctx_id = i915_execbuffer2_get_context_id(*args);
1626         u32 dispatch_flags;
1627         int ret;
1628         bool need_relocs;
1629
1630         if (!i915_gem_check_execbuffer(args))
1631                 return -EINVAL;
1632
1633         ret = validate_exec_list(dev, exec, args->buffer_count);
1634         if (ret)
1635                 return ret;
1636
1637         dispatch_flags = 0;
1638         if (args->flags & I915_EXEC_SECURE) {
1639                 if (!drm_is_current_master(file) || !capable(CAP_SYS_ADMIN))
1640                     return -EPERM;
1641
1642                 dispatch_flags |= I915_DISPATCH_SECURE;
1643         }
1644         if (args->flags & I915_EXEC_IS_PINNED)
1645                 dispatch_flags |= I915_DISPATCH_PINNED;
1646
1647         engine = eb_select_engine(dev_priv, file, args);
1648         if (!engine)
1649                 return -EINVAL;
1650
1651         if (args->buffer_count < 1) {
1652                 DRM_DEBUG("execbuf with %d buffers\n", args->buffer_count);
1653                 return -EINVAL;
1654         }
1655
1656         if (args->flags & I915_EXEC_RESOURCE_STREAMER) {
1657                 if (!HAS_RESOURCE_STREAMER(dev)) {
1658                         DRM_DEBUG("RS is only allowed for Haswell, Gen8 and above\n");
1659                         return -EINVAL;
1660                 }
1661                 if (engine->id != RCS) {
1662                         DRM_DEBUG("RS is not available on %s\n",
1663                                  engine->name);
1664                         return -EINVAL;
1665                 }
1666
1667                 dispatch_flags |= I915_DISPATCH_RS;
1668         }
1669
1670         /* Take a local wakeref for preparing to dispatch the execbuf as
1671          * we expect to access the hardware fairly frequently in the
1672          * process. Upon first dispatch, we acquire another prolonged
1673          * wakeref that we hold until the GPU has been idle for at least
1674          * 100ms.
1675          */
1676         intel_runtime_pm_get(dev_priv);
1677
1678         ret = i915_mutex_lock_interruptible(dev);
1679         if (ret)
1680                 goto pre_mutex_err;
1681
1682         ctx = i915_gem_validate_context(dev, file, engine, ctx_id);
1683         if (IS_ERR(ctx)) {
1684                 mutex_unlock(&dev->struct_mutex);
1685                 ret = PTR_ERR(ctx);
1686                 goto pre_mutex_err;
1687         }
1688
1689         i915_gem_context_get(ctx);
1690
1691         if (ctx->ppgtt)
1692                 vm = &ctx->ppgtt->base;
1693         else
1694                 vm = &ggtt->base;
1695
1696         memset(&params_master, 0x00, sizeof(params_master));
1697
1698         eb = eb_create(dev_priv, args);
1699         if (eb == NULL) {
1700                 i915_gem_context_put(ctx);
1701                 mutex_unlock(&dev->struct_mutex);
1702                 ret = -ENOMEM;
1703                 goto pre_mutex_err;
1704         }
1705
1706         /* Look up object handles */
1707         ret = eb_lookup_vmas(eb, exec, args, vm, file);
1708         if (ret)
1709                 goto err;
1710
1711         /* take note of the batch buffer before we might reorder the lists */
1712         params->batch = eb_get_batch(eb);
1713
1714         /* Move the objects en-masse into the GTT, evicting if necessary. */
1715         need_relocs = (args->flags & I915_EXEC_NO_RELOC) == 0;
1716         ret = i915_gem_execbuffer_reserve(engine, &eb->vmas, ctx,
1717                                           &need_relocs);
1718         if (ret)
1719                 goto err;
1720
1721         /* The objects are in their final locations, apply the relocations. */
1722         if (need_relocs)
1723                 ret = i915_gem_execbuffer_relocate(eb);
1724         if (ret) {
1725                 if (ret == -EFAULT) {
1726                         ret = i915_gem_execbuffer_relocate_slow(dev, args, file,
1727                                                                 engine,
1728                                                                 eb, exec, ctx);
1729                         BUG_ON(!mutex_is_locked(&dev->struct_mutex));
1730                 }
1731                 if (ret)
1732                         goto err;
1733         }
1734
1735         /* Set the pending read domains for the batch buffer to COMMAND */
1736         if (params->batch->obj->base.pending_write_domain) {
1737                 DRM_DEBUG("Attempting to use self-modifying batch buffer\n");
1738                 ret = -EINVAL;
1739                 goto err;
1740         }
1741         if (args->batch_start_offset > params->batch->size ||
1742             args->batch_len > params->batch->size - args->batch_start_offset) {
1743                 DRM_DEBUG("Attempting to use out-of-bounds batch\n");
1744                 ret = -EINVAL;
1745                 goto err;
1746         }
1747
1748         params->args_batch_start_offset = args->batch_start_offset;
1749         if (intel_engine_needs_cmd_parser(engine) && args->batch_len) {
1750                 struct i915_vma *vma;
1751
1752                 vma = i915_gem_execbuffer_parse(engine, &shadow_exec_entry,
1753                                                 params->batch->obj,
1754                                                 eb,
1755                                                 args->batch_start_offset,
1756                                                 args->batch_len,
1757                                                 drm_is_current_master(file));
1758                 if (IS_ERR(vma)) {
1759                         ret = PTR_ERR(vma);
1760                         goto err;
1761                 }
1762
1763                 if (vma) {
1764                         /*
1765                          * Batch parsed and accepted:
1766                          *
1767                          * Set the DISPATCH_SECURE bit to remove the NON_SECURE
1768                          * bit from MI_BATCH_BUFFER_START commands issued in
1769                          * the dispatch_execbuffer implementations. We
1770                          * specifically don't want that set on batches the
1771                          * command parser has accepted.
1772                          */
1773                         dispatch_flags |= I915_DISPATCH_SECURE;
1774                         params->args_batch_start_offset = 0;
1775                         params->batch = vma;
1776                 }
1777         }
1778
1779         params->batch->obj->base.pending_read_domains |= I915_GEM_DOMAIN_COMMAND;
1780
1781         /* snb/ivb/vlv conflate the "batch in ppgtt" bit with the "non-secure
1782          * batch" bit. Hence we need to pin secure batches into the global gtt.
1783          * hsw should have this fixed, but bdw mucks it up again. */
1784         if (dispatch_flags & I915_DISPATCH_SECURE) {
1785                 struct drm_i915_gem_object *obj = params->batch->obj;
1786                 struct i915_vma *vma;
1787
1788                 /*
1789                  * So on first glance it looks freaky that we pin the batch here
1790                  * outside of the reservation loop. But:
1791                  * - The batch is already pinned into the relevant ppgtt, so we
1792                  *   already have the backing storage fully allocated.
1793                  * - No other BO uses the global gtt (well contexts, but meh),
1794                  *   so we don't really have issues with multiple objects not
1795                  *   fitting due to fragmentation.
1796                  * So this is actually safe.
1797                  */
1798                 vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
1799                 if (IS_ERR(vma)) {
1800                         ret = PTR_ERR(vma);
1801                         goto err;
1802                 }
1803
1804                 params->batch = vma;
1805         }
1806
1807         /* Allocate a request for this batch buffer nice and early. */
1808         params->request = i915_gem_request_alloc(engine, ctx);
1809         if (IS_ERR(params->request)) {
1810                 ret = PTR_ERR(params->request);
1811                 goto err_batch_unpin;
1812         }
1813
1814         /* Whilst this request exists, batch_obj will be on the
1815          * active_list, and so will hold the active reference. Only when this
1816          * request is retired will the the batch_obj be moved onto the
1817          * inactive_list and lose its active reference. Hence we do not need
1818          * to explicitly hold another reference here.
1819          */
1820         params->request->batch = params->batch;
1821
1822         ret = i915_gem_request_add_to_client(params->request, file);
1823         if (ret)
1824                 goto err_request;
1825
1826         /*
1827          * Save assorted stuff away to pass through to *_submission().
1828          * NB: This data should be 'persistent' and not local as it will
1829          * kept around beyond the duration of the IOCTL once the GPU
1830          * scheduler arrives.
1831          */
1832         params->dev                     = dev;
1833         params->file                    = file;
1834         params->engine                    = engine;
1835         params->dispatch_flags          = dispatch_flags;
1836         params->ctx                     = ctx;
1837
1838         ret = execbuf_submit(params, args, &eb->vmas);
1839 err_request:
1840         __i915_add_request(params->request, ret == 0);
1841
1842 err_batch_unpin:
1843         /*
1844          * FIXME: We crucially rely upon the active tracking for the (ppgtt)
1845          * batch vma for correctness. For less ugly and less fragility this
1846          * needs to be adjusted to also track the ggtt batch vma properly as
1847          * active.
1848          */
1849         if (dispatch_flags & I915_DISPATCH_SECURE)
1850                 i915_vma_unpin(params->batch);
1851 err:
1852         /* the request owns the ref now */
1853         i915_gem_context_put(ctx);
1854         eb_destroy(eb);
1855
1856         mutex_unlock(&dev->struct_mutex);
1857
1858 pre_mutex_err:
1859         /* intel_gpu_busy should also get a ref, so it will free when the device
1860          * is really idle. */
1861         intel_runtime_pm_put(dev_priv);
1862         return ret;
1863 }
1864
1865 /*
1866  * Legacy execbuffer just creates an exec2 list from the original exec object
1867  * list array and passes it to the real function.
1868  */
1869 int
1870 i915_gem_execbuffer(struct drm_device *dev, void *data,
1871                     struct drm_file *file)
1872 {
1873         struct drm_i915_gem_execbuffer *args = data;
1874         struct drm_i915_gem_execbuffer2 exec2;
1875         struct drm_i915_gem_exec_object *exec_list = NULL;
1876         struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1877         int ret, i;
1878
1879         if (args->buffer_count < 1) {
1880                 DRM_DEBUG("execbuf with %d buffers\n", args->buffer_count);
1881                 return -EINVAL;
1882         }
1883
1884         /* Copy in the exec list from userland */
1885         exec_list = drm_malloc_ab(sizeof(*exec_list), args->buffer_count);
1886         exec2_list = drm_malloc_ab(sizeof(*exec2_list), args->buffer_count);
1887         if (exec_list == NULL || exec2_list == NULL) {
1888                 DRM_DEBUG("Failed to allocate exec list for %d buffers\n",
1889                           args->buffer_count);
1890                 drm_free_large(exec_list);
1891                 drm_free_large(exec2_list);
1892                 return -ENOMEM;
1893         }
1894         ret = copy_from_user(exec_list,
1895                              u64_to_user_ptr(args->buffers_ptr),
1896                              sizeof(*exec_list) * args->buffer_count);
1897         if (ret != 0) {
1898                 DRM_DEBUG("copy %d exec entries failed %d\n",
1899                           args->buffer_count, ret);
1900                 drm_free_large(exec_list);
1901                 drm_free_large(exec2_list);
1902                 return -EFAULT;
1903         }
1904
1905         for (i = 0; i < args->buffer_count; i++) {
1906                 exec2_list[i].handle = exec_list[i].handle;
1907                 exec2_list[i].relocation_count = exec_list[i].relocation_count;
1908                 exec2_list[i].relocs_ptr = exec_list[i].relocs_ptr;
1909                 exec2_list[i].alignment = exec_list[i].alignment;
1910                 exec2_list[i].offset = exec_list[i].offset;
1911                 if (INTEL_INFO(dev)->gen < 4)
1912                         exec2_list[i].flags = EXEC_OBJECT_NEEDS_FENCE;
1913                 else
1914                         exec2_list[i].flags = 0;
1915         }
1916
1917         exec2.buffers_ptr = args->buffers_ptr;
1918         exec2.buffer_count = args->buffer_count;
1919         exec2.batch_start_offset = args->batch_start_offset;
1920         exec2.batch_len = args->batch_len;
1921         exec2.DR1 = args->DR1;
1922         exec2.DR4 = args->DR4;
1923         exec2.num_cliprects = args->num_cliprects;
1924         exec2.cliprects_ptr = args->cliprects_ptr;
1925         exec2.flags = I915_EXEC_RENDER;
1926         i915_execbuffer2_set_context_id(exec2, 0);
1927
1928         ret = i915_gem_do_execbuffer(dev, data, file, &exec2, exec2_list);
1929         if (!ret) {
1930                 struct drm_i915_gem_exec_object __user *user_exec_list =
1931                         u64_to_user_ptr(args->buffers_ptr);
1932
1933                 /* Copy the new buffer offsets back to the user's exec list. */
1934                 for (i = 0; i < args->buffer_count; i++) {
1935                         exec2_list[i].offset =
1936                                 gen8_canonical_addr(exec2_list[i].offset);
1937                         ret = __copy_to_user(&user_exec_list[i].offset,
1938                                              &exec2_list[i].offset,
1939                                              sizeof(user_exec_list[i].offset));
1940                         if (ret) {
1941                                 ret = -EFAULT;
1942                                 DRM_DEBUG("failed to copy %d exec entries "
1943                                           "back to user (%d)\n",
1944                                           args->buffer_count, ret);
1945                                 break;
1946                         }
1947                 }
1948         }
1949
1950         drm_free_large(exec_list);
1951         drm_free_large(exec2_list);
1952         return ret;
1953 }
1954
1955 int
1956 i915_gem_execbuffer2(struct drm_device *dev, void *data,
1957                      struct drm_file *file)
1958 {
1959         struct drm_i915_gem_execbuffer2 *args = data;
1960         struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1961         int ret;
1962
1963         if (args->buffer_count < 1 ||
1964             args->buffer_count > UINT_MAX / sizeof(*exec2_list)) {
1965                 DRM_DEBUG("execbuf2 with %d buffers\n", args->buffer_count);
1966                 return -EINVAL;
1967         }
1968
1969         if (args->rsvd2 != 0) {
1970                 DRM_DEBUG("dirty rvsd2 field\n");
1971                 return -EINVAL;
1972         }
1973
1974         exec2_list = drm_malloc_gfp(args->buffer_count,
1975                                     sizeof(*exec2_list),
1976                                     GFP_TEMPORARY);
1977         if (exec2_list == NULL) {
1978                 DRM_DEBUG("Failed to allocate exec list for %d buffers\n",
1979                           args->buffer_count);
1980                 return -ENOMEM;
1981         }
1982         ret = copy_from_user(exec2_list,
1983                              u64_to_user_ptr(args->buffers_ptr),
1984                              sizeof(*exec2_list) * args->buffer_count);
1985         if (ret != 0) {
1986                 DRM_DEBUG("copy %d exec entries failed %d\n",
1987                           args->buffer_count, ret);
1988                 drm_free_large(exec2_list);
1989                 return -EFAULT;
1990         }
1991
1992         ret = i915_gem_do_execbuffer(dev, data, file, args, exec2_list);
1993         if (!ret) {
1994                 /* Copy the new buffer offsets back to the user's exec list. */
1995                 struct drm_i915_gem_exec_object2 __user *user_exec_list =
1996                                    u64_to_user_ptr(args->buffers_ptr);
1997                 int i;
1998
1999                 for (i = 0; i < args->buffer_count; i++) {
2000                         exec2_list[i].offset =
2001                                 gen8_canonical_addr(exec2_list[i].offset);
2002                         ret = __copy_to_user(&user_exec_list[i].offset,
2003                                              &exec2_list[i].offset,
2004                                              sizeof(user_exec_list[i].offset));
2005                         if (ret) {
2006                                 ret = -EFAULT;
2007                                 DRM_DEBUG("failed to copy %d exec entries "
2008                                           "back to user\n",
2009                                           args->buffer_count);
2010                                 break;
2011                         }
2012                 }
2013         }
2014
2015         drm_free_large(exec2_list);
2016         return ret;
2017 }