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  * $FreeBSD: src/sys/dev/drm2/i915/i915_gem_execbuffer.c,v 1.3 2012/05/28 13:58:08 kib Exp $
28  */
29 
30 #include <sys/limits.h>
31 #include <sys/sfbuf.h>
32 
33 #include <drm/drmP.h>
34 #include <drm/i915_drm.h>
35 #include "i915_drv.h"
36 #include "intel_drv.h"
37 
38 struct change_domains {
39 	uint32_t invalidate_domains;
40 	uint32_t flush_domains;
41 	uint32_t flush_rings;
42 	uint32_t flips;
43 };
44 
45 /*
46  * Set the next domain for the specified object. This
47  * may not actually perform the necessary flushing/invaliding though,
48  * as that may want to be batched with other set_domain operations
49  *
50  * This is (we hope) the only really tricky part of gem. The goal
51  * is fairly simple -- track which caches hold bits of the object
52  * and make sure they remain coherent. A few concrete examples may
53  * help to explain how it works. For shorthand, we use the notation
54  * (read_domains, write_domain), e.g. (CPU, CPU) to indicate the
55  * a pair of read and write domain masks.
56  *
57  * Case 1: the batch buffer
58  *
59  *	1. Allocated
60  *	2. Written by CPU
61  *	3. Mapped to GTT
62  *	4. Read by GPU
63  *	5. Unmapped from GTT
64  *	6. Freed
65  *
66  *	Let's take these a step at a time
67  *
68  *	1. Allocated
69  *		Pages allocated from the kernel may still have
70  *		cache contents, so we set them to (CPU, CPU) always.
71  *	2. Written by CPU (using pwrite)
72  *		The pwrite function calls set_domain (CPU, CPU) and
73  *		this function does nothing (as nothing changes)
74  *	3. Mapped by GTT
75  *		This function asserts that the object is not
76  *		currently in any GPU-based read or write domains
77  *	4. Read by GPU
78  *		i915_gem_execbuffer calls set_domain (COMMAND, 0).
79  *		As write_domain is zero, this function adds in the
80  *		current read domains (CPU+COMMAND, 0).
81  *		flush_domains is set to CPU.
82  *		invalidate_domains is set to COMMAND
83  *		clflush is run to get data out of the CPU caches
84  *		then i915_dev_set_domain calls i915_gem_flush to
85  *		emit an MI_FLUSH and drm_agp_chipset_flush
86  *	5. Unmapped from GTT
87  *		i915_gem_object_unbind calls set_domain (CPU, CPU)
88  *		flush_domains and invalidate_domains end up both zero
89  *		so no flushing/invalidating happens
90  *	6. Freed
91  *		yay, done
92  *
93  * Case 2: The shared render buffer
94  *
95  *	1. Allocated
96  *	2. Mapped to GTT
97  *	3. Read/written by GPU
98  *	4. set_domain to (CPU,CPU)
99  *	5. Read/written by CPU
100  *	6. Read/written by GPU
101  *
102  *	1. Allocated
103  *		Same as last example, (CPU, CPU)
104  *	2. Mapped to GTT
105  *		Nothing changes (assertions find that it is not in the GPU)
106  *	3. Read/written by GPU
107  *		execbuffer calls set_domain (RENDER, RENDER)
108  *		flush_domains gets CPU
109  *		invalidate_domains gets GPU
110  *		clflush (obj)
111  *		MI_FLUSH and drm_agp_chipset_flush
112  *	4. set_domain (CPU, CPU)
113  *		flush_domains gets GPU
114  *		invalidate_domains gets CPU
115  *		wait_rendering (obj) to make sure all drawing is complete.
116  *		This will include an MI_FLUSH to get the data from GPU
117  *		to memory
118  *		clflush (obj) to invalidate the CPU cache
119  *		Another MI_FLUSH in i915_gem_flush (eliminate this somehow?)
120  *	5. Read/written by CPU
121  *		cache lines are loaded and dirtied
122  *	6. Read written by GPU
123  *		Same as last GPU access
124  *
125  * Case 3: The constant buffer
126  *
127  *	1. Allocated
128  *	2. Written by CPU
129  *	3. Read by GPU
130  *	4. Updated (written) by CPU again
131  *	5. Read by GPU
132  *
133  *	1. Allocated
134  *		(CPU, CPU)
135  *	2. Written by CPU
136  *		(CPU, CPU)
137  *	3. Read by GPU
138  *		(CPU+RENDER, 0)
139  *		flush_domains = CPU
140  *		invalidate_domains = RENDER
141  *		clflush (obj)
142  *		MI_FLUSH
143  *		drm_agp_chipset_flush
144  *	4. Updated (written) by CPU again
145  *		(CPU, CPU)
146  *		flush_domains = 0 (no previous write domain)
147  *		invalidate_domains = 0 (no new read domains)
148  *	5. Read by GPU
149  *		(CPU+RENDER, 0)
150  *		flush_domains = CPU
151  *		invalidate_domains = RENDER
152  *		clflush (obj)
153  *		MI_FLUSH
154  *		drm_agp_chipset_flush
155  */
156 static void
157 i915_gem_object_set_to_gpu_domain(struct drm_i915_gem_object *obj,
158 				  struct intel_ring_buffer *ring,
159 				  struct change_domains *cd)
160 {
161 	uint32_t invalidate_domains = 0, flush_domains = 0;
162 
163 	/*
164 	 * If the object isn't moving to a new write domain,
165 	 * let the object stay in multiple read domains
166 	 */
167 	if (obj->base.pending_write_domain == 0)
168 		obj->base.pending_read_domains |= obj->base.read_domains;
169 
170 	/*
171 	 * Flush the current write domain if
172 	 * the new read domains don't match. Invalidate
173 	 * any read domains which differ from the old
174 	 * write domain
175 	 */
176 	if (obj->base.write_domain &&
177 	    (((obj->base.write_domain != obj->base.pending_read_domains ||
178 	       obj->ring != ring)) ||
179 	     (obj->fenced_gpu_access && !obj->pending_fenced_gpu_access))) {
180 		flush_domains |= obj->base.write_domain;
181 		invalidate_domains |=
182 			obj->base.pending_read_domains & ~obj->base.write_domain;
183 	}
184 	/*
185 	 * Invalidate any read caches which may have
186 	 * stale data. That is, any new read domains.
187 	 */
188 	invalidate_domains |= obj->base.pending_read_domains & ~obj->base.read_domains;
189 	if ((flush_domains | invalidate_domains) & I915_GEM_DOMAIN_CPU)
190 		i915_gem_clflush_object(obj);
191 
192 	if (obj->base.pending_write_domain)
193 		cd->flips |= atomic_load_acq_int(&obj->pending_flip);
194 
195 	/* The actual obj->write_domain will be updated with
196 	 * pending_write_domain after we emit the accumulated flush for all
197 	 * of our domain changes in execbuffers (which clears objects'
198 	 * write_domains).  So if we have a current write domain that we
199 	 * aren't changing, set pending_write_domain to that.
200 	 */
201 	if (flush_domains == 0 && obj->base.pending_write_domain == 0)
202 		obj->base.pending_write_domain = obj->base.write_domain;
203 
204 	cd->invalidate_domains |= invalidate_domains;
205 	cd->flush_domains |= flush_domains;
206 	if (flush_domains & I915_GEM_GPU_DOMAINS)
207 		cd->flush_rings |= intel_ring_flag(obj->ring);
208 	if (invalidate_domains & I915_GEM_GPU_DOMAINS)
209 		cd->flush_rings |= intel_ring_flag(ring);
210 }
211 
212 struct eb_objects {
213 	int and;
214 	struct hlist_head buckets[0];
215 };
216 
217 static struct eb_objects *
218 eb_create(int size)
219 {
220 	struct eb_objects *eb;
221 	int count = PAGE_SIZE / sizeof(struct hlist_head) / 2;
222 	while (count > size)
223 		count >>= 1;
224 #if 0
225 	eb = kzalloc(count*sizeof(struct hlist_head) +
226 		     sizeof(struct eb_objects),
227 		     GFP_KERNEL);
228 #else
229 	eb = kmalloc(count*sizeof(struct hlist_head) +
230 		     sizeof(struct eb_objects),
231 		     DRM_I915_GEM, M_WAITOK | M_ZERO);
232 #endif
233 	if (eb == NULL)
234 		return eb;
235 
236 	eb->and = count - 1;
237 	return eb;
238 }
239 
240 static void
241 eb_reset(struct eb_objects *eb)
242 {
243 	memset(eb->buckets, 0, (eb->and+1)*sizeof(struct hlist_head));
244 }
245 
246 static void
247 eb_add_object(struct eb_objects *eb, struct drm_i915_gem_object *obj)
248 {
249 	hlist_add_head(&obj->exec_node,
250 		       &eb->buckets[obj->exec_handle & eb->and]);
251 }
252 
253 static struct drm_i915_gem_object *
254 eb_get_object(struct eb_objects *eb, unsigned long handle)
255 {
256 	struct hlist_head *head;
257 	struct hlist_node *node;
258 	struct drm_i915_gem_object *obj;
259 
260 	head = &eb->buckets[handle & eb->and];
261 	hlist_for_each(node, head) {
262 		obj = hlist_entry(node, struct drm_i915_gem_object, exec_node);
263 		if (obj->exec_handle == handle)
264 			return obj;
265 	}
266 
267 	return NULL;
268 }
269 
270 static void
271 eb_destroy(struct eb_objects *eb)
272 {
273 	drm_free(eb, DRM_I915_GEM);
274 }
275 
276 static int
277 i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj,
278 				   struct eb_objects *eb,
279 				   struct drm_i915_gem_relocation_entry *reloc)
280 {
281 	struct drm_device *dev = obj->base.dev;
282 	struct drm_gem_object *target_obj;
283 	uint32_t target_offset;
284 	int ret = -EINVAL;
285 
286 	/* we've already hold a reference to all valid objects */
287 	target_obj = &eb_get_object(eb, reloc->target_handle)->base;
288 	if (unlikely(target_obj == NULL))
289 		return -ENOENT;
290 
291 	target_offset = to_intel_bo(target_obj)->gtt_offset;
292 
293 #if WATCH_RELOC
294 	DRM_INFO("%s: obj %p offset %08x target %d "
295 		 "read %08x write %08x gtt %08x "
296 		 "presumed %08x delta %08x\n",
297 		 __func__,
298 		 obj,
299 		 (int) reloc->offset,
300 		 (int) reloc->target_handle,
301 		 (int) reloc->read_domains,
302 		 (int) reloc->write_domain,
303 		 (int) target_offset,
304 		 (int) reloc->presumed_offset,
305 		 reloc->delta);
306 #endif
307 
308 	/* The target buffer should have appeared before us in the
309 	 * exec_object list, so it should have a GTT space bound by now.
310 	 */
311 	if (unlikely(target_offset == 0)) {
312 		DRM_DEBUG("No GTT space found for object %d\n",
313 			  reloc->target_handle);
314 		return ret;
315 	}
316 
317 	/* Validate that the target is in a valid r/w GPU domain */
318 	if (unlikely(reloc->write_domain & (reloc->write_domain - 1))) {
319 		DRM_DEBUG("reloc with multiple write domains: "
320 			  "obj %p target %d offset %d "
321 			  "read %08x write %08x",
322 			  obj, reloc->target_handle,
323 			  (int) reloc->offset,
324 			  reloc->read_domains,
325 			  reloc->write_domain);
326 		return ret;
327 	}
328 	if (unlikely((reloc->write_domain | reloc->read_domains)
329 		     & ~I915_GEM_GPU_DOMAINS)) {
330 		DRM_DEBUG("reloc with read/write non-GPU domains: "
331 			  "obj %p target %d offset %d "
332 			  "read %08x write %08x",
333 			  obj, reloc->target_handle,
334 			  (int) reloc->offset,
335 			  reloc->read_domains,
336 			  reloc->write_domain);
337 		return ret;
338 	}
339 	if (unlikely(reloc->write_domain && target_obj->pending_write_domain &&
340 		     reloc->write_domain != target_obj->pending_write_domain)) {
341 		DRM_DEBUG("Write domain conflict: "
342 			  "obj %p target %d offset %d "
343 			  "new %08x old %08x\n",
344 			  obj, reloc->target_handle,
345 			  (int) reloc->offset,
346 			  reloc->write_domain,
347 			  target_obj->pending_write_domain);
348 		return ret;
349 	}
350 
351 	target_obj->pending_read_domains |= reloc->read_domains;
352 	target_obj->pending_write_domain |= reloc->write_domain;
353 
354 	/* If the relocation already has the right value in it, no
355 	 * more work needs to be done.
356 	 */
357 	if (target_offset == reloc->presumed_offset)
358 		return 0;
359 
360 	/* Check that the relocation address is valid... */
361 	if (unlikely(reloc->offset > obj->base.size - 4)) {
362 		DRM_DEBUG("Relocation beyond object bounds: "
363 			  "obj %p target %d offset %d size %d.\n",
364 			  obj, reloc->target_handle,
365 			  (int) reloc->offset,
366 			  (int) obj->base.size);
367 		return ret;
368 	}
369 	if (unlikely(reloc->offset & 3)) {
370 		DRM_DEBUG("Relocation not 4-byte aligned: "
371 			  "obj %p target %d offset %d.\n",
372 			  obj, reloc->target_handle,
373 			  (int) reloc->offset);
374 		return ret;
375 	}
376 
377 	reloc->delta += target_offset;
378 	if (obj->base.write_domain == I915_GEM_DOMAIN_CPU) {
379 		uint32_t page_offset = reloc->offset & PAGE_MASK;
380 		char *vaddr;
381 		struct sf_buf *sf;
382 
383 		sf = sf_buf_alloc(obj->pages[OFF_TO_IDX(reloc->offset)]);
384 		if (sf == NULL)
385 			return (-ENOMEM);
386 		vaddr = (void *)sf_buf_kva(sf);
387 		*(uint32_t *)(vaddr + page_offset) = reloc->delta;
388 		sf_buf_free(sf);
389 	} else {
390 		uint32_t *reloc_entry;
391 		char *reloc_page;
392 
393 		/* We can't wait for rendering with pagefaults disabled */
394 		if (obj->active && (curthread->td_flags & TDF_NOFAULT))
395 			return (-EFAULT);
396 		ret = i915_gem_object_set_to_gtt_domain(obj, 1);
397 		if (ret)
398 			return ret;
399 
400 		/*
401 		 * Map the page containing the relocation we're going
402 		 * to perform.
403 		 */
404 		reloc->offset += obj->gtt_offset;
405 		reloc_page = pmap_mapdev_attr(dev->agp->base + (reloc->offset &
406 		    ~PAGE_MASK), PAGE_SIZE, PAT_WRITE_COMBINING);
407 		reloc_entry = (uint32_t *)(reloc_page + (reloc->offset &
408 		    PAGE_MASK));
409 		*(volatile uint32_t *)reloc_entry = reloc->delta;
410 		pmap_unmapdev((vm_offset_t)reloc_page, PAGE_SIZE);
411 	}
412 
413 	/* and update the user's relocation entry */
414 	reloc->presumed_offset = target_offset;
415 
416 	return 0;
417 }
418 
419 static int
420 i915_gem_execbuffer_relocate_object(struct drm_i915_gem_object *obj,
421     struct eb_objects *eb)
422 {
423 	struct drm_i915_gem_relocation_entry *user_relocs;
424 	struct drm_i915_gem_exec_object2 *entry = obj->exec_entry;
425 	struct drm_i915_gem_relocation_entry reloc;
426 	int i, ret;
427 
428 	user_relocs = (void *)(uintptr_t)entry->relocs_ptr;
429 	for (i = 0; i < entry->relocation_count; i++) {
430 		ret = -copyin_nofault(user_relocs + i, &reloc, sizeof(reloc));
431 		if (ret != 0)
432 			return (ret);
433 
434 		ret = i915_gem_execbuffer_relocate_entry(obj, eb, &reloc);
435 		if (ret != 0)
436 			return (ret);
437 
438 		ret = -copyout_nofault(&reloc.presumed_offset,
439 		    &user_relocs[i].presumed_offset,
440 		    sizeof(reloc.presumed_offset));
441 		if (ret != 0)
442 			return (ret);
443 	}
444 
445 	return (0);
446 }
447 
448 static int
449 i915_gem_execbuffer_relocate_object_slow(struct drm_i915_gem_object *obj,
450     struct eb_objects *eb, struct drm_i915_gem_relocation_entry *relocs)
451 {
452 	const struct drm_i915_gem_exec_object2 *entry = obj->exec_entry;
453 	int i, ret;
454 
455 	for (i = 0; i < entry->relocation_count; i++) {
456 		ret = i915_gem_execbuffer_relocate_entry(obj, eb, &relocs[i]);
457 		if (ret)
458 			return ret;
459 	}
460 
461 	return 0;
462 }
463 
464 static int
465 i915_gem_execbuffer_relocate(struct drm_device *dev,
466 			     struct eb_objects *eb,
467 			     struct list_head *objects)
468 {
469 	struct drm_i915_gem_object *obj;
470 	thread_t td = curthread;
471 	int ret;
472 	int pflags;
473 
474 	/* Try to move as many of the relocation targets off the active list
475 	 * to avoid unnecessary fallbacks to the slow path, as we cannot wait
476 	 * for the retirement with pagefaults disabled.
477 	 */
478 	i915_gem_retire_requests(dev);
479 
480 	ret = 0;
481 	pflags = td->td_flags & TDF_NOFAULT;
482 	atomic_set_int(&td->td_flags, TDF_NOFAULT);
483 
484 	/* This is the fast path and we cannot handle a pagefault whilst
485 	 * holding the device lock lest the user pass in the relocations
486 	 * contained within a mmaped bo. For in such a case we, the page
487 	 * fault handler would call i915_gem_fault() and we would try to
488 	 * acquire the device lock again. Obviously this is bad.
489 	 */
490 
491 	list_for_each_entry(obj, objects, exec_list) {
492 		ret = i915_gem_execbuffer_relocate_object(obj, eb);
493 		if (ret != 0)
494 			break;
495 	}
496 
497 	if ((pflags & TDF_NOFAULT) == 0)
498 		atomic_clear_int(&td->td_flags, TDF_NOFAULT);
499 
500 	return (ret);
501 }
502 
503 #define  __EXEC_OBJECT_HAS_FENCE (1<<31)
504 
505 static int
506 pin_and_fence_object(struct drm_i915_gem_object *obj,
507 		     struct intel_ring_buffer *ring)
508 {
509 	struct drm_i915_gem_exec_object2 *entry = obj->exec_entry;
510 	bool has_fenced_gpu_access = INTEL_INFO(ring->dev)->gen < 4;
511 	bool need_fence, need_mappable;
512 	int ret;
513 
514 	need_fence =
515 		has_fenced_gpu_access &&
516 		entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
517 		obj->tiling_mode != I915_TILING_NONE;
518 	need_mappable =
519 		entry->relocation_count ? true : need_fence;
520 
521 	ret = i915_gem_object_pin(obj, entry->alignment, need_mappable);
522 	if (ret)
523 		return ret;
524 
525 	if (has_fenced_gpu_access) {
526 		if (entry->flags & EXEC_OBJECT_NEEDS_FENCE) {
527 			if (obj->tiling_mode) {
528 				ret = i915_gem_object_get_fence(obj, ring);
529 				if (ret)
530 					goto err_unpin;
531 
532 				entry->flags |= __EXEC_OBJECT_HAS_FENCE;
533 				i915_gem_object_pin_fence(obj);
534 			} else {
535 				ret = i915_gem_object_put_fence(obj);
536 				if (ret)
537 					goto err_unpin;
538 			}
539 			obj->pending_fenced_gpu_access = true;
540 		}
541 	}
542 
543 	entry->offset = obj->gtt_offset;
544 	return 0;
545 
546 err_unpin:
547 	i915_gem_object_unpin(obj);
548 	return ret;
549 }
550 
551 static int
552 i915_gem_execbuffer_reserve(struct intel_ring_buffer *ring,
553 			    struct drm_file *file,
554 			    struct list_head *objects)
555 {
556 	drm_i915_private_t *dev_priv;
557 	struct drm_i915_gem_object *obj;
558 	int ret, retry;
559 	bool has_fenced_gpu_access = INTEL_INFO(ring->dev)->gen < 4;
560 	struct list_head ordered_objects;
561 
562 	dev_priv = ring->dev->dev_private;
563 	INIT_LIST_HEAD(&ordered_objects);
564 	while (!list_empty(objects)) {
565 		struct drm_i915_gem_exec_object2 *entry;
566 		bool need_fence, need_mappable;
567 
568 		obj = list_first_entry(objects,
569 				       struct drm_i915_gem_object,
570 				       exec_list);
571 		entry = obj->exec_entry;
572 
573 		need_fence =
574 			has_fenced_gpu_access &&
575 			entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
576 			obj->tiling_mode != I915_TILING_NONE;
577 		need_mappable =
578 			entry->relocation_count ? true : need_fence;
579 
580 		if (need_mappable)
581 			list_move(&obj->exec_list, &ordered_objects);
582 		else
583 			list_move_tail(&obj->exec_list, &ordered_objects);
584 
585 		obj->base.pending_read_domains = 0;
586 		obj->base.pending_write_domain = 0;
587 	}
588 	list_splice(&ordered_objects, objects);
589 
590 	/* Attempt to pin all of the buffers into the GTT.
591 	 * This is done in 3 phases:
592 	 *
593 	 * 1a. Unbind all objects that do not match the GTT constraints for
594 	 *     the execbuffer (fenceable, mappable, alignment etc).
595 	 * 1b. Increment pin count for already bound objects and obtain
596 	 *     a fence register if required.
597 	 * 2.  Bind new objects.
598 	 * 3.  Decrement pin count.
599 	 *
600 	 * This avoid unnecessary unbinding of later objects in order to makr
601 	 * room for the earlier objects *unless* we need to defragment.
602 	 */
603 	retry = 0;
604 	do {
605 		ret = 0;
606 
607 		/* Unbind any ill-fitting objects or pin. */
608 		list_for_each_entry(obj, objects, exec_list) {
609 			struct drm_i915_gem_exec_object2 *entry = obj->exec_entry;
610 			bool need_fence, need_mappable;
611 
612 			if (!obj->gtt_space)
613 				continue;
614 
615 			need_fence =
616 				has_fenced_gpu_access &&
617 				entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
618 				obj->tiling_mode != I915_TILING_NONE;
619 			need_mappable =
620 				entry->relocation_count ? true : need_fence;
621 
622 			if ((entry->alignment && obj->gtt_offset & (entry->alignment - 1)) ||
623 			    (need_mappable && !obj->map_and_fenceable))
624 				ret = i915_gem_object_unbind(obj);
625 			else
626 				ret = pin_and_fence_object(obj, ring);
627 			if (ret)
628 				goto err;
629 		}
630 
631 		/* Bind fresh objects */
632 		list_for_each_entry(obj, objects, exec_list) {
633 			if (obj->gtt_space)
634 				continue;
635 
636 			ret = pin_and_fence_object(obj, ring);
637 			if (ret) {
638 				int ret_ignore;
639 
640 				/* This can potentially raise a harmless
641 				 * -EINVAL if we failed to bind in the above
642 				 * call. It cannot raise -EINTR since we know
643 				 * that the bo is freshly bound and so will
644 				 * not need to be flushed or waited upon.
645 				 */
646 				ret_ignore = i915_gem_object_unbind(obj);
647 				(void)ret_ignore;
648 				if (obj->gtt_space != NULL)
649 					kprintf("%s: gtt_space\n", __func__);
650 				break;
651 			}
652 		}
653 
654 		/* Decrement pin count for bound objects */
655 		list_for_each_entry(obj, objects, exec_list) {
656 			struct drm_i915_gem_exec_object2 *entry;
657 
658 			if (!obj->gtt_space)
659 				continue;
660 
661 			entry = obj->exec_entry;
662 			if (entry->flags & __EXEC_OBJECT_HAS_FENCE) {
663 				i915_gem_object_unpin_fence(obj);
664 				entry->flags &= ~__EXEC_OBJECT_HAS_FENCE;
665 			}
666 
667 			i915_gem_object_unpin(obj);
668 
669 			/* ... and ensure ppgtt mapping exist if needed. */
670 			if (dev_priv->mm.aliasing_ppgtt && !obj->has_aliasing_ppgtt_mapping) {
671 				i915_ppgtt_bind_object(dev_priv->mm.aliasing_ppgtt,
672 						       obj, obj->cache_level);
673 
674 				obj->has_aliasing_ppgtt_mapping = 1;
675 			}
676 		}
677 
678 		if (ret != -ENOSPC || retry > 1)
679 			return ret;
680 
681 		/* First attempt, just clear anything that is purgeable.
682 		 * Second attempt, clear the entire GTT.
683 		 */
684 		ret = i915_gem_evict_everything(ring->dev, retry == 0);
685 		if (ret)
686 			return ret;
687 
688 		retry++;
689 	} while (1);
690 
691 err:
692 	list_for_each_entry_continue_reverse(obj, objects, exec_list) {
693 		struct drm_i915_gem_exec_object2 *entry;
694 
695 		if (!obj->gtt_space)
696 			continue;
697 
698 		entry = obj->exec_entry;
699 		if (entry->flags & __EXEC_OBJECT_HAS_FENCE) {
700 			i915_gem_object_unpin_fence(obj);
701 			entry->flags &= ~__EXEC_OBJECT_HAS_FENCE;
702 		}
703 
704 		i915_gem_object_unpin(obj);
705 	}
706 
707 	return ret;
708 }
709 
710 static int
711 i915_gem_execbuffer_relocate_slow(struct drm_device *dev,
712     struct drm_file *file, struct intel_ring_buffer *ring,
713     struct list_head *objects, struct eb_objects *eb,
714     struct drm_i915_gem_exec_object2 *exec, int count)
715 {
716 	struct drm_i915_gem_relocation_entry *reloc;
717 	struct drm_i915_gem_object *obj;
718 	int *reloc_offset;
719 	int i, total, ret;
720 
721 	/* We may process another execbuffer during the unlock... */
722 	while (!list_empty(objects)) {
723 		obj = list_first_entry(objects,
724 				       struct drm_i915_gem_object,
725 				       exec_list);
726 		list_del_init(&obj->exec_list);
727 		drm_gem_object_unreference(&obj->base);
728 	}
729 
730 	DRM_UNLOCK(dev);
731 
732 	total = 0;
733 	for (i = 0; i < count; i++)
734 		total += exec[i].relocation_count;
735 
736 	reloc_offset = kmalloc(count * sizeof(*reloc_offset), DRM_I915_GEM,
737 	    M_WAITOK | M_ZERO);
738 	reloc = kmalloc(total * sizeof(*reloc), DRM_I915_GEM, M_WAITOK | M_ZERO);
739 
740 	total = 0;
741 	for (i = 0; i < count; i++) {
742 		struct drm_i915_gem_relocation_entry *user_relocs;
743 
744 		user_relocs = (void *)(uintptr_t)exec[i].relocs_ptr;
745 		ret = -copyin(user_relocs, reloc + total,
746 		    exec[i].relocation_count * sizeof(*reloc));
747 		if (ret != 0) {
748 			DRM_LOCK(dev);
749 			goto err;
750 		}
751 
752 		reloc_offset[i] = total;
753 		total += exec[i].relocation_count;
754 	}
755 
756 	ret = i915_mutex_lock_interruptible(dev);
757 	if (ret) {
758 		DRM_LOCK(dev);
759 		goto err;
760 	}
761 
762 	/* reacquire the objects */
763 	eb_reset(eb);
764 	for (i = 0; i < count; i++) {
765 		struct drm_i915_gem_object *obj;
766 
767 		obj = to_intel_bo(drm_gem_object_lookup(dev, file,
768 							exec[i].handle));
769 		if (&obj->base == NULL) {
770 			DRM_DEBUG("Invalid object handle %d at index %d\n",
771 				   exec[i].handle, i);
772 			ret = -ENOENT;
773 			goto err;
774 		}
775 
776 		list_add_tail(&obj->exec_list, objects);
777 		obj->exec_handle = exec[i].handle;
778 		obj->exec_entry = &exec[i];
779 		eb_add_object(eb, obj);
780 	}
781 
782 	ret = i915_gem_execbuffer_reserve(ring, file, objects);
783 	if (ret)
784 		goto err;
785 
786 	list_for_each_entry(obj, objects, exec_list) {
787 		int offset = obj->exec_entry - exec;
788 		ret = i915_gem_execbuffer_relocate_object_slow(obj, eb,
789 		    reloc + reloc_offset[offset]);
790 		if (ret)
791 			goto err;
792 	}
793 
794 	/* Leave the user relocations as are, this is the painfully slow path,
795 	 * and we want to avoid the complication of dropping the lock whilst
796 	 * having buffers reserved in the aperture and so causing spurious
797 	 * ENOSPC for random operations.
798 	 */
799 
800 err:
801 	drm_free(reloc, DRM_I915_GEM);
802 	drm_free(reloc_offset, DRM_I915_GEM);
803 	return ret;
804 }
805 
806 static int
807 i915_gem_execbuffer_flush(struct drm_device *dev,
808 			  uint32_t invalidate_domains,
809 			  uint32_t flush_domains,
810 			  uint32_t flush_rings)
811 {
812 	drm_i915_private_t *dev_priv = dev->dev_private;
813 	int i, ret;
814 
815 	if (flush_domains & I915_GEM_DOMAIN_CPU)
816 		intel_gtt_chipset_flush();
817 
818 	if (flush_domains & I915_GEM_DOMAIN_GTT)
819 		cpu_sfence();
820 
821 	if ((flush_domains | invalidate_domains) & I915_GEM_GPU_DOMAINS) {
822 		for (i = 0; i < I915_NUM_RINGS; i++)
823 			if (flush_rings & (1 << i)) {
824 				ret = i915_gem_flush_ring(&dev_priv->rings[i],
825 				    invalidate_domains, flush_domains);
826 				if (ret)
827 					return ret;
828 			}
829 	}
830 
831 	return 0;
832 }
833 
834 static bool
835 intel_enable_semaphores(struct drm_device *dev)
836 {
837 	if (INTEL_INFO(dev)->gen < 6)
838 		return 0;
839 
840 	if (i915_semaphores >= 0)
841 		return i915_semaphores;
842 
843 	/* Enable semaphores on SNB when IO remapping is off */
844 	if (INTEL_INFO(dev)->gen == 6)
845 		return !intel_iommu_enabled;
846 
847 	return 1;
848 }
849 
850 static int
851 i915_gem_execbuffer_sync_rings(struct drm_i915_gem_object *obj,
852 			       struct intel_ring_buffer *to)
853 {
854 	struct intel_ring_buffer *from = obj->ring;
855 	u32 seqno;
856 	int ret, idx;
857 
858 	if (from == NULL || to == from)
859 		return 0;
860 
861 	/* XXX gpu semaphores are implicated in various hard hangs on SNB */
862 	if (!intel_enable_semaphores(obj->base.dev))
863 		return i915_gem_object_wait_rendering(obj);
864 
865 	idx = intel_ring_sync_index(from, to);
866 
867 	seqno = obj->last_rendering_seqno;
868 	if (seqno <= from->sync_seqno[idx])
869 		return 0;
870 
871 	if (seqno == from->outstanding_lazy_request) {
872 		struct drm_i915_gem_request *request;
873 
874 		request = kmalloc(sizeof(*request), DRM_I915_GEM,
875 		    M_WAITOK | M_ZERO);
876 		ret = i915_add_request(from, NULL, request);
877 		if (ret) {
878 			drm_free(request, DRM_I915_GEM);
879 			return ret;
880 		}
881 
882 		seqno = request->seqno;
883 	}
884 
885 	from->sync_seqno[idx] = seqno;
886 
887 	return to->sync_to(to, from, seqno - 1);
888 }
889 
890 static int
891 i915_gem_execbuffer_wait_for_flips(struct intel_ring_buffer *ring, u32 flips)
892 {
893 	u32 plane, flip_mask;
894 	int ret;
895 
896 	/* Check for any pending flips. As we only maintain a flip queue depth
897 	 * of 1, we can simply insert a WAIT for the next display flip prior
898 	 * to executing the batch and avoid stalling the CPU.
899 	 */
900 
901 	for (plane = 0; flips >> plane; plane++) {
902 		if (((flips >> plane) & 1) == 0)
903 			continue;
904 
905 		if (plane)
906 			flip_mask = MI_WAIT_FOR_PLANE_B_FLIP;
907 		else
908 			flip_mask = MI_WAIT_FOR_PLANE_A_FLIP;
909 
910 		ret = intel_ring_begin(ring, 2);
911 		if (ret)
912 			return ret;
913 
914 		intel_ring_emit(ring, MI_WAIT_FOR_EVENT | flip_mask);
915 		intel_ring_emit(ring, MI_NOOP);
916 		intel_ring_advance(ring);
917 	}
918 
919 	return 0;
920 }
921 
922 static int
923 i915_gem_execbuffer_move_to_gpu(struct intel_ring_buffer *ring,
924 				struct list_head *objects)
925 {
926 	struct drm_i915_gem_object *obj;
927 	struct change_domains cd;
928 	int ret;
929 
930 	memset(&cd, 0, sizeof(cd));
931 	list_for_each_entry(obj, objects, exec_list)
932 		i915_gem_object_set_to_gpu_domain(obj, ring, &cd);
933 
934 	if (cd.invalidate_domains | cd.flush_domains) {
935 #if WATCH_EXEC
936 		DRM_INFO("%s: invalidate_domains %08x flush_domains %08x\n",
937 			  __func__,
938 			 cd.invalidate_domains,
939 			 cd.flush_domains);
940 #endif
941 		ret = i915_gem_execbuffer_flush(ring->dev,
942 						cd.invalidate_domains,
943 						cd.flush_domains,
944 						cd.flush_rings);
945 		if (ret)
946 			return ret;
947 	}
948 
949 	if (cd.flips) {
950 		ret = i915_gem_execbuffer_wait_for_flips(ring, cd.flips);
951 		if (ret)
952 			return ret;
953 	}
954 
955 	list_for_each_entry(obj, objects, exec_list) {
956 		ret = i915_gem_execbuffer_sync_rings(obj, ring);
957 		if (ret)
958 			return ret;
959 	}
960 
961 	return 0;
962 }
963 
964 static bool
965 i915_gem_check_execbuffer(struct drm_i915_gem_execbuffer2 *exec)
966 {
967 	return ((exec->batch_start_offset | exec->batch_len) & 0x7) == 0;
968 }
969 
970 static int
971 validate_exec_list(struct drm_i915_gem_exec_object2 *exec, int count,
972     vm_page_t ***map)
973 {
974 	vm_page_t *ma;
975 	int i, length, page_count;
976 
977 	/* XXXKIB various limits checking is missing there */
978 	*map = kmalloc(count * sizeof(*ma), DRM_I915_GEM, M_WAITOK | M_ZERO);
979 	for (i = 0; i < count; i++) {
980 		/* First check for malicious input causing overflow */
981 		if (exec[i].relocation_count >
982 		    INT_MAX / sizeof(struct drm_i915_gem_relocation_entry))
983 			return -EINVAL;
984 
985 		length = exec[i].relocation_count *
986 		    sizeof(struct drm_i915_gem_relocation_entry);
987 		if (length == 0) {
988 			(*map)[i] = NULL;
989 			continue;
990 		}
991 		/*
992 		 * Since both start and end of the relocation region
993 		 * may be not aligned on the page boundary, be
994 		 * conservative and request a page slot for each
995 		 * partial page.  Thus +2.
996 		 */
997 		page_count = howmany(length, PAGE_SIZE) + 2;
998 		ma = (*map)[i] = kmalloc(page_count * sizeof(vm_page_t),
999 		    DRM_I915_GEM, M_WAITOK | M_ZERO);
1000 		if (vm_fault_quick_hold_pages(&curproc->p_vmspace->vm_map,
1001 		    exec[i].relocs_ptr, length, VM_PROT_READ | VM_PROT_WRITE,
1002 		    ma, page_count) == -1) {
1003 			drm_free(ma, DRM_I915_GEM);
1004 			(*map)[i] = NULL;
1005 			return (-EFAULT);
1006 		}
1007 	}
1008 
1009 	return 0;
1010 }
1011 
1012 static void
1013 i915_gem_execbuffer_move_to_active(struct list_head *objects,
1014 				   struct intel_ring_buffer *ring,
1015 				   u32 seqno)
1016 {
1017 	struct drm_i915_gem_object *obj;
1018 	uint32_t old_read, old_write;
1019 
1020 	list_for_each_entry(obj, objects, exec_list) {
1021 		old_read = obj->base.read_domains;
1022 		old_write = obj->base.write_domain;
1023 
1024 		obj->base.read_domains = obj->base.pending_read_domains;
1025 		obj->base.write_domain = obj->base.pending_write_domain;
1026 		obj->fenced_gpu_access = obj->pending_fenced_gpu_access;
1027 
1028 		i915_gem_object_move_to_active(obj, ring, seqno);
1029 		if (obj->base.write_domain) {
1030 			obj->dirty = 1;
1031 			obj->pending_gpu_write = true;
1032 			list_move_tail(&obj->gpu_write_list,
1033 				       &ring->gpu_write_list);
1034 			intel_mark_busy(ring->dev, obj);
1035 		}
1036 	}
1037 }
1038 
1039 int i915_gem_sync_exec_requests;
1040 
1041 static void
1042 i915_gem_execbuffer_retire_commands(struct drm_device *dev,
1043 				    struct drm_file *file,
1044 				    struct intel_ring_buffer *ring)
1045 {
1046 	struct drm_i915_gem_request *request;
1047 	u32 invalidate;
1048 
1049 	/*
1050 	 * Ensure that the commands in the batch buffer are
1051 	 * finished before the interrupt fires.
1052 	 *
1053 	 * The sampler always gets flushed on i965 (sigh).
1054 	 */
1055 	invalidate = I915_GEM_DOMAIN_COMMAND;
1056 	if (INTEL_INFO(dev)->gen >= 4)
1057 		invalidate |= I915_GEM_DOMAIN_SAMPLER;
1058 	if (ring->flush(ring, invalidate, 0)) {
1059 		i915_gem_next_request_seqno(ring);
1060 		return;
1061 	}
1062 
1063 	/* Add a breadcrumb for the completion of the batch buffer */
1064 	request = kmalloc(sizeof(*request), DRM_I915_GEM, M_WAITOK | M_ZERO);
1065 	if (request == NULL || i915_add_request(ring, file, request)) {
1066 		i915_gem_next_request_seqno(ring);
1067 		drm_free(request, DRM_I915_GEM);
1068 	} else if (i915_gem_sync_exec_requests)
1069 		i915_wait_request(ring, request->seqno, true);
1070 }
1071 
1072 static void
1073 i915_gem_fix_mi_batchbuffer_end(struct drm_i915_gem_object *batch_obj,
1074     uint32_t batch_start_offset, uint32_t batch_len)
1075 {
1076 	char *mkva;
1077 	uint64_t po_r, po_w;
1078 	uint32_t cmd;
1079 
1080 	po_r = batch_obj->base.dev->agp->base + batch_obj->gtt_offset +
1081 	    batch_start_offset + batch_len;
1082 	if (batch_len > 0)
1083 		po_r -= 4;
1084 	mkva = pmap_mapdev_attr(trunc_page(po_r), 2 * PAGE_SIZE,
1085 	    PAT_WRITE_COMBINING);
1086 	po_r &= PAGE_MASK;
1087 	cmd = *(uint32_t *)(mkva + po_r);
1088 
1089 	if (cmd != MI_BATCH_BUFFER_END) {
1090 		/*
1091 		 * batch_len != 0 due to the check at the start of
1092 		 * i915_gem_do_execbuffer
1093 		 */
1094 		if (batch_obj->base.size > batch_start_offset + batch_len) {
1095 			po_w = po_r + 4;
1096 /* DRM_DEBUG("batchbuffer does not end by MI_BATCH_BUFFER_END !\n"); */
1097 		} else {
1098 			po_w = po_r;
1099 DRM_DEBUG("batchbuffer does not end by MI_BATCH_BUFFER_END, overwriting last bo cmd !\n");
1100 		}
1101 		*(uint32_t *)(mkva + po_w) = MI_BATCH_BUFFER_END;
1102 	}
1103 
1104 	pmap_unmapdev((vm_offset_t)mkva, 2 * PAGE_SIZE);
1105 }
1106 
1107 int i915_fix_mi_batchbuffer_end = 0;
1108 
1109  static int
1110 i915_reset_gen7_sol_offsets(struct drm_device *dev,
1111 			    struct intel_ring_buffer *ring)
1112 {
1113 	drm_i915_private_t *dev_priv = dev->dev_private;
1114 	int ret, i;
1115 
1116 	if (!IS_GEN7(dev) || ring != &dev_priv->rings[RCS])
1117 		return 0;
1118 
1119 	ret = intel_ring_begin(ring, 4 * 3);
1120 	if (ret)
1121 		return ret;
1122 
1123 	for (i = 0; i < 4; i++) {
1124 		intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
1125 		intel_ring_emit(ring, GEN7_SO_WRITE_OFFSET(i));
1126 		intel_ring_emit(ring, 0);
1127 	}
1128 
1129 	intel_ring_advance(ring);
1130 
1131 	return 0;
1132 }
1133 
1134 static int
1135 i915_gem_do_execbuffer(struct drm_device *dev, void *data,
1136 		       struct drm_file *file,
1137 		       struct drm_i915_gem_execbuffer2 *args,
1138 		       struct drm_i915_gem_exec_object2 *exec)
1139 {
1140 	drm_i915_private_t *dev_priv = dev->dev_private;
1141 	struct list_head objects;
1142 	struct eb_objects *eb;
1143 	struct drm_i915_gem_object *batch_obj;
1144 	struct drm_clip_rect *cliprects = NULL;
1145 	struct intel_ring_buffer *ring;
1146 	vm_page_t **relocs_ma;
1147 	u32 exec_start, exec_len;
1148 	u32 seqno;
1149 	u32 mask;
1150 	int ret, mode, i;
1151 
1152 	if (!i915_gem_check_execbuffer(args)) {
1153 		DRM_DEBUG("execbuf with invalid offset/length\n");
1154 		return -EINVAL;
1155 	}
1156 
1157 	if (args->batch_len == 0)
1158 		return (0);
1159 
1160 	ret = validate_exec_list(exec, args->buffer_count, &relocs_ma);
1161 	if (ret != 0)
1162 		goto pre_struct_lock_err;
1163 
1164 	switch (args->flags & I915_EXEC_RING_MASK) {
1165 	case I915_EXEC_DEFAULT:
1166 	case I915_EXEC_RENDER:
1167 		ring = &dev_priv->rings[RCS];
1168 		break;
1169 	case I915_EXEC_BSD:
1170 		if (!HAS_BSD(dev)) {
1171 			DRM_DEBUG("execbuf with invalid ring (BSD)\n");
1172 			return -EINVAL;
1173 		}
1174 		ring = &dev_priv->rings[VCS];
1175 		break;
1176 	case I915_EXEC_BLT:
1177 		if (!HAS_BLT(dev)) {
1178 			DRM_DEBUG("execbuf with invalid ring (BLT)\n");
1179 			return -EINVAL;
1180 		}
1181 		ring = &dev_priv->rings[BCS];
1182 		break;
1183 	default:
1184 		DRM_DEBUG("execbuf with unknown ring: %d\n",
1185 			  (int)(args->flags & I915_EXEC_RING_MASK));
1186 		ret = -EINVAL;
1187 		goto pre_struct_lock_err;
1188 	}
1189 
1190 	mode = args->flags & I915_EXEC_CONSTANTS_MASK;
1191 	mask = I915_EXEC_CONSTANTS_MASK;
1192 	switch (mode) {
1193 	case I915_EXEC_CONSTANTS_REL_GENERAL:
1194 	case I915_EXEC_CONSTANTS_ABSOLUTE:
1195 	case I915_EXEC_CONSTANTS_REL_SURFACE:
1196 		if (ring == &dev_priv->rings[RCS] &&
1197 		    mode != dev_priv->relative_constants_mode) {
1198 			if (INTEL_INFO(dev)->gen < 4) {
1199 				ret = -EINVAL;
1200 				goto pre_struct_lock_err;
1201 			}
1202 
1203 			if (INTEL_INFO(dev)->gen > 5 &&
1204 			    mode == I915_EXEC_CONSTANTS_REL_SURFACE) {
1205 				ret = -EINVAL;
1206 				goto pre_struct_lock_err;
1207 			}
1208 
1209 			/* The HW changed the meaning on this bit on gen6 */
1210 			if (INTEL_INFO(dev)->gen >= 6)
1211 				mask &= ~I915_EXEC_CONSTANTS_REL_SURFACE;
1212 		}
1213 		break;
1214 	default:
1215 		DRM_DEBUG("execbuf with unknown constants: %d\n", mode);
1216 		ret = -EINVAL;
1217 		goto pre_struct_lock_err;
1218 	}
1219 
1220 	if (args->buffer_count < 1) {
1221 		DRM_DEBUG("execbuf with %d buffers\n", args->buffer_count);
1222 		ret = -EINVAL;
1223 		goto pre_struct_lock_err;
1224 	}
1225 
1226 	if (args->num_cliprects != 0) {
1227 		if (ring != &dev_priv->rings[RCS]) {
1228 	DRM_DEBUG("clip rectangles are only valid with the render ring\n");
1229 			ret = -EINVAL;
1230 			goto pre_struct_lock_err;
1231 		}
1232 
1233 		if (args->num_cliprects > UINT_MAX / sizeof(*cliprects)) {
1234 			DRM_DEBUG("execbuf with %u cliprects\n",
1235 				  args->num_cliprects);
1236 			ret = -EINVAL;
1237 			goto pre_struct_lock_err;
1238 		}
1239 		cliprects = kmalloc( sizeof(*cliprects) * args->num_cliprects,
1240 		    DRM_I915_GEM, M_WAITOK | M_ZERO);
1241 		ret = -copyin((void *)(uintptr_t)args->cliprects_ptr, cliprects,
1242 		    sizeof(*cliprects) * args->num_cliprects);
1243 		if (ret != 0)
1244 			goto pre_struct_lock_err;
1245 	}
1246 
1247 	ret = i915_mutex_lock_interruptible(dev);
1248 	if (ret)
1249 		goto pre_struct_lock_err;
1250 
1251 	if (dev_priv->mm.suspended) {
1252 		ret = -EBUSY;
1253 		goto struct_lock_err;
1254 	}
1255 
1256 	eb = eb_create(args->buffer_count);
1257 	if (eb == NULL) {
1258 		ret = -ENOMEM;
1259 		goto struct_lock_err;
1260 	}
1261 
1262 	/* Look up object handles */
1263 	INIT_LIST_HEAD(&objects);
1264 	for (i = 0; i < args->buffer_count; i++) {
1265 		struct drm_i915_gem_object *obj;
1266 		obj = to_intel_bo(drm_gem_object_lookup(dev, file,
1267 							exec[i].handle));
1268 		if (&obj->base == NULL) {
1269 			DRM_DEBUG("Invalid object handle %d at index %d\n",
1270 				   exec[i].handle, i);
1271 			/* prevent error path from reading uninitialized data */
1272 			ret = -ENOENT;
1273 			goto err;
1274 		}
1275 
1276 		if (!list_empty(&obj->exec_list)) {
1277 			DRM_DEBUG("Object %p [handle %d, index %d] appears more than once in object list\n",
1278 				   obj, exec[i].handle, i);
1279 			ret = -EINVAL;
1280 			goto err;
1281 		}
1282 
1283 		list_add_tail(&obj->exec_list, &objects);
1284 		obj->exec_handle = exec[i].handle;
1285 		obj->exec_entry = &exec[i];
1286 		eb_add_object(eb, obj);
1287 	}
1288 
1289 	/* take note of the batch buffer before we might reorder the lists */
1290 	batch_obj = list_entry(objects.prev,
1291 			       struct drm_i915_gem_object,
1292 			       exec_list);
1293 
1294 	/* Move the objects en-masse into the GTT, evicting if necessary. */
1295 	ret = i915_gem_execbuffer_reserve(ring, file, &objects);
1296 	if (ret)
1297 		goto err;
1298 
1299 	/* The objects are in their final locations, apply the relocations. */
1300 	ret = i915_gem_execbuffer_relocate(dev, eb, &objects);
1301 	if (ret) {
1302 		if (ret == -EFAULT) {
1303 			ret = i915_gem_execbuffer_relocate_slow(dev, file, ring,
1304 			    &objects, eb, exec,	args->buffer_count);
1305 			DRM_LOCK_ASSERT(dev);
1306 		}
1307 		if (ret)
1308 			goto err;
1309 	}
1310 
1311 	/* Set the pending read domains for the batch buffer to COMMAND */
1312 	if (batch_obj->base.pending_write_domain) {
1313 		DRM_DEBUG("Attempting to use self-modifying batch buffer\n");
1314 		ret = -EINVAL;
1315 		goto err;
1316 	}
1317 	batch_obj->base.pending_read_domains |= I915_GEM_DOMAIN_COMMAND;
1318 
1319 	ret = i915_gem_execbuffer_move_to_gpu(ring, &objects);
1320 	if (ret)
1321 		goto err;
1322 
1323 	seqno = i915_gem_next_request_seqno(ring);
1324 	for (i = 0; i < I915_NUM_RINGS - 1; i++) {
1325 		if (seqno < ring->sync_seqno[i]) {
1326 			/* The GPU can not handle its semaphore value wrapping,
1327 			 * so every billion or so execbuffers, we need to stall
1328 			 * the GPU in order to reset the counters.
1329 			 */
1330 			ret = i915_gpu_idle(dev, true);
1331 			if (ret)
1332 				goto err;
1333 
1334 			KASSERT(ring->sync_seqno[i] == 0, ("Non-zero sync_seqno"));
1335 		}
1336 	}
1337 
1338 	if (ring == &dev_priv->rings[RCS] &&
1339 	    mode != dev_priv->relative_constants_mode) {
1340 		ret = intel_ring_begin(ring, 4);
1341 		if (ret)
1342 			goto err;
1343 
1344 		intel_ring_emit(ring, MI_NOOP);
1345 		intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
1346 		intel_ring_emit(ring, INSTPM);
1347 		intel_ring_emit(ring, mask << 16 | mode);
1348 		intel_ring_advance(ring);
1349 
1350 		dev_priv->relative_constants_mode = mode;
1351 	}
1352 
1353 	if (args->flags & I915_EXEC_GEN7_SOL_RESET) {
1354 		ret = i915_reset_gen7_sol_offsets(dev, ring);
1355 		if (ret)
1356 			goto err;
1357 	}
1358 
1359 	exec_start = batch_obj->gtt_offset + args->batch_start_offset;
1360 	exec_len = args->batch_len;
1361 
1362 	if (i915_fix_mi_batchbuffer_end) {
1363 		i915_gem_fix_mi_batchbuffer_end(batch_obj,
1364 		    args->batch_start_offset, args->batch_len);
1365 	}
1366 
1367 	if (cliprects) {
1368 		for (i = 0; i < args->num_cliprects; i++) {
1369 			ret = i915_emit_box_p(dev, &cliprects[i],
1370 			    args->DR1, args->DR4);
1371 			if (ret)
1372 				goto err;
1373 
1374 			ret = ring->dispatch_execbuffer(ring, exec_start,
1375 			    exec_len);
1376 			if (ret)
1377 				goto err;
1378 		}
1379 	} else {
1380 		ret = ring->dispatch_execbuffer(ring, exec_start, exec_len);
1381 		if (ret)
1382 			goto err;
1383 	}
1384 
1385 	i915_gem_execbuffer_move_to_active(&objects, ring, seqno);
1386 	i915_gem_execbuffer_retire_commands(dev, file, ring);
1387 
1388 err:
1389 	eb_destroy(eb);
1390 	while (!list_empty(&objects)) {
1391 		struct drm_i915_gem_object *obj;
1392 
1393 		obj = list_first_entry(&objects, struct drm_i915_gem_object,
1394 		    exec_list);
1395 		list_del_init(&obj->exec_list);
1396 		drm_gem_object_unreference(&obj->base);
1397 	}
1398 struct_lock_err:
1399 	DRM_UNLOCK(dev);
1400 
1401 pre_struct_lock_err:
1402 	for (i = 0; i < args->buffer_count; i++) {
1403 		if (relocs_ma[i] != NULL) {
1404 			vm_page_unhold_pages(relocs_ma[i], howmany(
1405 			    exec[i].relocation_count *
1406 			    sizeof(struct drm_i915_gem_relocation_entry),
1407 			    PAGE_SIZE));
1408 			drm_free(relocs_ma[i], DRM_I915_GEM);
1409 		}
1410 	}
1411 	drm_free(relocs_ma, DRM_I915_GEM);
1412 	drm_free(cliprects, DRM_I915_GEM);
1413 	return ret;
1414 }
1415 
1416 /*
1417  * Legacy execbuffer just creates an exec2 list from the original exec object
1418  * list array and passes it to the real function.
1419  */
1420 int
1421 i915_gem_execbuffer(struct drm_device *dev, void *data,
1422 		    struct drm_file *file)
1423 {
1424 	struct drm_i915_gem_execbuffer *args = data;
1425 	struct drm_i915_gem_execbuffer2 exec2;
1426 	struct drm_i915_gem_exec_object *exec_list = NULL;
1427 	struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1428 	int ret, i;
1429 
1430 	DRM_DEBUG("buffers_ptr %d buffer_count %d len %08x\n",
1431 	    (int) args->buffers_ptr, args->buffer_count, args->batch_len);
1432 
1433 	if (args->buffer_count < 1) {
1434 		DRM_DEBUG("execbuf with %d buffers\n", args->buffer_count);
1435 		return -EINVAL;
1436 	}
1437 
1438 	/* Copy in the exec list from userland */
1439 	/* XXXKIB user-controlled malloc size */
1440 	exec_list = kmalloc(sizeof(*exec_list) * args->buffer_count,
1441 	    DRM_I915_GEM, M_WAITOK);
1442 	exec2_list = kmalloc(sizeof(*exec2_list) * args->buffer_count,
1443 	    DRM_I915_GEM, M_WAITOK);
1444 	ret = -copyin((void *)(uintptr_t)args->buffers_ptr, exec_list,
1445 	    sizeof(*exec_list) * args->buffer_count);
1446 	if (ret != 0) {
1447 		DRM_DEBUG("copy %d exec entries failed %d\n",
1448 			  args->buffer_count, ret);
1449 		drm_free(exec_list, DRM_I915_GEM);
1450 		drm_free(exec2_list, DRM_I915_GEM);
1451 		return (ret);
1452 	}
1453 
1454 	for (i = 0; i < args->buffer_count; i++) {
1455 		exec2_list[i].handle = exec_list[i].handle;
1456 		exec2_list[i].relocation_count = exec_list[i].relocation_count;
1457 		exec2_list[i].relocs_ptr = exec_list[i].relocs_ptr;
1458 		exec2_list[i].alignment = exec_list[i].alignment;
1459 		exec2_list[i].offset = exec_list[i].offset;
1460 		if (INTEL_INFO(dev)->gen < 4)
1461 			exec2_list[i].flags = EXEC_OBJECT_NEEDS_FENCE;
1462 		else
1463 			exec2_list[i].flags = 0;
1464 	}
1465 
1466 	exec2.buffers_ptr = args->buffers_ptr;
1467 	exec2.buffer_count = args->buffer_count;
1468 	exec2.batch_start_offset = args->batch_start_offset;
1469 	exec2.batch_len = args->batch_len;
1470 	exec2.DR1 = args->DR1;
1471 	exec2.DR4 = args->DR4;
1472 	exec2.num_cliprects = args->num_cliprects;
1473 	exec2.cliprects_ptr = args->cliprects_ptr;
1474 	exec2.flags = I915_EXEC_RENDER;
1475 
1476 	ret = i915_gem_do_execbuffer(dev, data, file, &exec2, exec2_list);
1477 	if (!ret) {
1478 		/* Copy the new buffer offsets back to the user's exec list. */
1479 		for (i = 0; i < args->buffer_count; i++)
1480 			exec_list[i].offset = exec2_list[i].offset;
1481 		/* ... and back out to userspace */
1482 		ret = -copyout(exec_list, (void *)(uintptr_t)args->buffers_ptr,
1483 		    sizeof(*exec_list) * args->buffer_count);
1484 		if (ret != 0) {
1485 			DRM_DEBUG("failed to copy %d exec entries "
1486 				  "back to user (%d)\n",
1487 				  args->buffer_count, ret);
1488 		}
1489 	}
1490 
1491 	drm_free(exec_list, DRM_I915_GEM);
1492 	drm_free(exec2_list, DRM_I915_GEM);
1493 	return ret;
1494 }
1495 
1496 int
1497 i915_gem_execbuffer2(struct drm_device *dev, void *data,
1498 		     struct drm_file *file)
1499 {
1500 	struct drm_i915_gem_execbuffer2 *args = data;
1501 	struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1502 	int ret;
1503 
1504 	DRM_DEBUG("buffers_ptr %jx buffer_count %d len %08x\n",
1505 	    (uintmax_t)args->buffers_ptr, args->buffer_count, args->batch_len);
1506 
1507 	if (args->buffer_count < 1 ||
1508 	    args->buffer_count > UINT_MAX / sizeof(*exec2_list)) {
1509 		DRM_DEBUG("execbuf2 with %d buffers\n", args->buffer_count);
1510 		return -EINVAL;
1511 	}
1512 
1513 	/* XXXKIB user-controllable kmalloc size */
1514 	exec2_list = kmalloc(sizeof(*exec2_list) * args->buffer_count,
1515 	    DRM_I915_GEM, M_WAITOK);
1516 	ret = -copyin((void *)(uintptr_t)args->buffers_ptr, exec2_list,
1517 	    sizeof(*exec2_list) * args->buffer_count);
1518 	if (ret != 0) {
1519 		DRM_DEBUG("copy %d exec entries failed %d\n",
1520 			  args->buffer_count, ret);
1521 		drm_free(exec2_list, DRM_I915_GEM);
1522 		return (ret);
1523 	}
1524 
1525 	ret = i915_gem_do_execbuffer(dev, data, file, args, exec2_list);
1526 	if (!ret) {
1527 		/* Copy the new buffer offsets back to the user's exec list. */
1528 		ret = -copyout(exec2_list, (void *)(uintptr_t)args->buffers_ptr,
1529 		    sizeof(*exec2_list) * args->buffer_count);
1530 		if (ret) {
1531 			DRM_DEBUG("failed to copy %d exec entries "
1532 				  "back to user (%d)\n",
1533 				  args->buffer_count, ret);
1534 		}
1535 	}
1536 
1537 	drm_free(exec2_list, DRM_I915_GEM);
1538 	return ret;
1539 }
1540