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 <drm/drmP.h>
30 #include <drm/i915_drm.h>
31 #include "i915_drv.h"
32 #include "i915_trace.h"
33 #include "intel_drv.h"
34 #include <linux/pagemap.h>
35 #include <asm/cpufeature.h>
36 
37 #define  __EXEC_OBJECT_HAS_PIN (1<<31)
38 #define  __EXEC_OBJECT_HAS_FENCE (1<<30)
39 #define  __EXEC_OBJECT_NEEDS_MAP (1<<29)
40 #define  __EXEC_OBJECT_NEEDS_BIAS (1<<28)
41 
42 #define BATCH_OFFSET_BIAS (256*1024)
43 
44 struct eb_vmas {
45 	struct list_head vmas;
46 	int and;
47 	union {
48 		struct i915_vma *lut[0];
49 		struct hlist_head buckets[0];
50 	};
51 };
52 
53 static struct eb_vmas *
54 eb_create(struct drm_i915_gem_execbuffer2 *args)
55 {
56 	struct eb_vmas *eb = NULL;
57 
58 	if (args->flags & I915_EXEC_HANDLE_LUT) {
59 		unsigned size = args->buffer_count;
60 		size *= sizeof(struct i915_vma *);
61 		size += sizeof(struct eb_vmas);
62 		eb = kmalloc(size, M_DRM, M_NOWAIT);
63 	}
64 
65 	if (eb == NULL) {
66 		unsigned size = args->buffer_count;
67 		unsigned count = PAGE_SIZE / sizeof(struct hlist_head) / 2;
68 		BUILD_BUG_ON_NOT_POWER_OF_2(PAGE_SIZE / sizeof(struct hlist_head));
69 		while (count > 2*size)
70 			count >>= 1;
71 		eb = kzalloc(count*sizeof(struct hlist_head) +
72 			     sizeof(struct eb_vmas),
73 			     GFP_TEMPORARY);
74 		if (eb == NULL)
75 			return eb;
76 
77 		eb->and = count - 1;
78 	} else
79 		eb->and = -args->buffer_count;
80 
81 	INIT_LIST_HEAD(&eb->vmas);
82 	return eb;
83 }
84 
85 static void
86 eb_reset(struct eb_vmas *eb)
87 {
88 	if (eb->and >= 0)
89 		memset(eb->buckets, 0, (eb->and+1)*sizeof(struct hlist_head));
90 }
91 
92 static int
93 eb_lookup_vmas(struct eb_vmas *eb,
94 	       struct drm_i915_gem_exec_object2 *exec,
95 	       const struct drm_i915_gem_execbuffer2 *args,
96 	       struct i915_address_space *vm,
97 	       struct drm_file *file)
98 {
99 	struct drm_i915_gem_object *obj;
100 	struct list_head objects;
101 	int i, ret;
102 
103 	INIT_LIST_HEAD(&objects);
104 	lockmgr(&file->table_lock, LK_EXCLUSIVE);
105 	/* Grab a reference to the object and release the lock so we can lookup
106 	 * or create the VMA without using GFP_ATOMIC */
107 	for (i = 0; i < args->buffer_count; i++) {
108 		obj = to_intel_bo(idr_find(&file->object_idr, exec[i].handle));
109 		if (obj == NULL) {
110 			lockmgr(&file->table_lock, LK_RELEASE);
111 			DRM_DEBUG("Invalid object handle %d at index %d\n",
112 				   exec[i].handle, i);
113 			ret = -ENOENT;
114 			goto err;
115 		}
116 
117 		if (!list_empty(&obj->obj_exec_link)) {
118 			lockmgr(&file->table_lock, LK_RELEASE);
119 			DRM_DEBUG("Object %p [handle %d, index %d] appears more than once in object list\n",
120 				   obj, exec[i].handle, i);
121 			ret = -EINVAL;
122 			goto err;
123 		}
124 
125 		drm_gem_object_reference(&obj->base);
126 		list_add_tail(&obj->obj_exec_link, &objects);
127 	}
128 	lockmgr(&file->table_lock, LK_RELEASE);
129 
130 	i = 0;
131 	while (!list_empty(&objects)) {
132 		struct i915_vma *vma;
133 
134 		obj = list_first_entry(&objects,
135 				       struct drm_i915_gem_object,
136 				       obj_exec_link);
137 
138 		/*
139 		 * NOTE: We can leak any vmas created here when something fails
140 		 * later on. But that's no issue since vma_unbind can deal with
141 		 * vmas which are not actually bound. And since only
142 		 * lookup_or_create exists as an interface to get at the vma
143 		 * from the (obj, vm) we don't run the risk of creating
144 		 * duplicated vmas for the same vm.
145 		 */
146 		vma = i915_gem_obj_lookup_or_create_vma(obj, vm);
147 		if (IS_ERR(vma)) {
148 			DRM_DEBUG("Failed to lookup VMA\n");
149 			ret = PTR_ERR(vma);
150 			goto err;
151 		}
152 
153 		/* Transfer ownership from the objects list to the vmas list. */
154 		list_add_tail(&vma->exec_list, &eb->vmas);
155 		list_del_init(&obj->obj_exec_link);
156 
157 		vma->exec_entry = &exec[i];
158 		if (eb->and < 0) {
159 			eb->lut[i] = vma;
160 		} else {
161 			uint32_t handle = args->flags & I915_EXEC_HANDLE_LUT ? i : exec[i].handle;
162 			vma->exec_handle = handle;
163 			hlist_add_head(&vma->exec_node,
164 				       &eb->buckets[handle & eb->and]);
165 		}
166 		++i;
167 	}
168 
169 	return 0;
170 
171 
172 err:
173 	while (!list_empty(&objects)) {
174 		obj = list_first_entry(&objects,
175 				       struct drm_i915_gem_object,
176 				       obj_exec_link);
177 		list_del_init(&obj->obj_exec_link);
178 		drm_gem_object_unreference(&obj->base);
179 	}
180 	/*
181 	 * Objects already transfered to the vmas list will be unreferenced by
182 	 * eb_destroy.
183 	 */
184 
185 	return ret;
186 }
187 
188 static struct i915_vma *eb_get_vma(struct eb_vmas *eb, unsigned long handle)
189 {
190 	if (eb->and < 0) {
191 		if (handle >= -eb->and)
192 			return NULL;
193 		return eb->lut[handle];
194 	} else {
195 		struct hlist_head *head;
196 		struct hlist_node *node;
197 
198 		head = &eb->buckets[handle & eb->and];
199 		hlist_for_each(node, head) {
200 			struct i915_vma *vma;
201 
202 			vma = hlist_entry(node, struct i915_vma, exec_node);
203 			if (vma->exec_handle == handle)
204 				return vma;
205 		}
206 		return NULL;
207 	}
208 }
209 
210 static void
211 i915_gem_execbuffer_unreserve_vma(struct i915_vma *vma)
212 {
213 	struct drm_i915_gem_exec_object2 *entry;
214 	struct drm_i915_gem_object *obj = vma->obj;
215 
216 	if (!drm_mm_node_allocated(&vma->node))
217 		return;
218 
219 	entry = vma->exec_entry;
220 
221 	if (entry->flags & __EXEC_OBJECT_HAS_FENCE)
222 		i915_gem_object_unpin_fence(obj);
223 
224 	if (entry->flags & __EXEC_OBJECT_HAS_PIN)
225 		vma->pin_count--;
226 
227 	entry->flags &= ~(__EXEC_OBJECT_HAS_FENCE | __EXEC_OBJECT_HAS_PIN);
228 }
229 
230 static void eb_destroy(struct eb_vmas *eb)
231 {
232 	while (!list_empty(&eb->vmas)) {
233 		struct i915_vma *vma;
234 
235 		vma = list_first_entry(&eb->vmas,
236 				       struct i915_vma,
237 				       exec_list);
238 		list_del_init(&vma->exec_list);
239 		i915_gem_execbuffer_unreserve_vma(vma);
240 		drm_gem_object_unreference(&vma->obj->base);
241 	}
242 	kfree(eb);
243 }
244 
245 static inline int use_cpu_reloc(struct drm_i915_gem_object *obj)
246 {
247 	return (HAS_LLC(obj->base.dev) ||
248 		obj->base.write_domain == I915_GEM_DOMAIN_CPU ||
249 		obj->cache_level != I915_CACHE_NONE);
250 }
251 
252 static int
253 relocate_entry_cpu(struct drm_i915_gem_object *obj,
254 		   struct drm_i915_gem_relocation_entry *reloc,
255 		   uint64_t target_offset)
256 {
257 	struct drm_device *dev = obj->base.dev;
258 	uint32_t page_offset = offset_in_page(reloc->offset);
259 	uint64_t delta = reloc->delta + target_offset;
260 	char *vaddr;
261 	int ret;
262 
263 	ret = i915_gem_object_set_to_cpu_domain(obj, true);
264 	if (ret)
265 		return ret;
266 
267 	vaddr = kmap_atomic(i915_gem_object_get_page(obj,
268 				reloc->offset >> PAGE_SHIFT));
269 	*(uint32_t *)(vaddr + page_offset) = lower_32_bits(delta);
270 
271 	if (INTEL_INFO(dev)->gen >= 8) {
272 		page_offset = offset_in_page(page_offset + sizeof(uint32_t));
273 
274 		if (page_offset == 0) {
275 			kunmap_atomic(vaddr);
276 			vaddr = kmap_atomic(i915_gem_object_get_page(obj,
277 			    (reloc->offset + sizeof(uint32_t)) >> PAGE_SHIFT));
278 		}
279 
280 		*(uint32_t *)(vaddr + page_offset) = upper_32_bits(delta);
281 	}
282 
283 	kunmap_atomic(vaddr);
284 
285 	return 0;
286 }
287 
288 static int
289 relocate_entry_gtt(struct drm_i915_gem_object *obj,
290 		   struct drm_i915_gem_relocation_entry *reloc,
291 		   uint64_t target_offset)
292 {
293 	struct drm_device *dev = obj->base.dev;
294 	struct drm_i915_private *dev_priv = dev->dev_private;
295 	uint64_t delta = reloc->delta + target_offset;
296 	uint64_t offset;
297 	void __iomem *reloc_page;
298 	int ret;
299 
300 	ret = i915_gem_object_set_to_gtt_domain(obj, true);
301 	if (ret)
302 		return ret;
303 
304 	ret = i915_gem_object_put_fence(obj);
305 	if (ret)
306 		return ret;
307 
308 	/* Map the page containing the relocation we're going to perform.  */
309 	offset = i915_gem_obj_ggtt_offset(obj);
310 	offset += reloc->offset;
311 	reloc_page = io_mapping_map_atomic_wc(dev_priv->gtt.mappable,
312 					      offset & ~PAGE_MASK);
313 	iowrite32(lower_32_bits(delta), reloc_page + offset_in_page(offset));
314 
315 	if (INTEL_INFO(dev)->gen >= 8) {
316 		offset += sizeof(uint32_t);
317 
318 		if (offset_in_page(offset) == 0) {
319 			io_mapping_unmap_atomic(reloc_page);
320 			reloc_page =
321 				io_mapping_map_atomic_wc(dev_priv->gtt.mappable,
322 							 offset);
323 		}
324 
325 		iowrite32(upper_32_bits(delta),
326 			  reloc_page + offset_in_page(offset));
327 	}
328 
329 	io_mapping_unmap_atomic(reloc_page);
330 
331 	return 0;
332 }
333 
334 static void
335 clflush_write32(void *addr, uint32_t value)
336 {
337 	/* This is not a fast path, so KISS. */
338 	drm_clflush_virt_range(addr, sizeof(uint32_t));
339 	*(uint32_t *)addr = value;
340 	drm_clflush_virt_range(addr, sizeof(uint32_t));
341 }
342 
343 static int
344 relocate_entry_clflush(struct drm_i915_gem_object *obj,
345 		       struct drm_i915_gem_relocation_entry *reloc,
346 		       uint64_t target_offset)
347 {
348 	struct drm_device *dev = obj->base.dev;
349 	uint32_t page_offset = offset_in_page(reloc->offset);
350 	uint64_t delta = (int)reloc->delta + target_offset;
351 	char *vaddr;
352 	int ret;
353 
354 	ret = i915_gem_object_set_to_gtt_domain(obj, true);
355 	if (ret)
356 		return ret;
357 
358 	vaddr = kmap_atomic(i915_gem_object_get_page(obj,
359 				reloc->offset >> PAGE_SHIFT));
360 	clflush_write32(vaddr + page_offset, lower_32_bits(delta));
361 
362 	if (INTEL_INFO(dev)->gen >= 8) {
363 		page_offset = offset_in_page(page_offset + sizeof(uint32_t));
364 
365 		if (page_offset == 0) {
366 			kunmap_atomic(vaddr);
367 			vaddr = kmap_atomic(i915_gem_object_get_page(obj,
368 			    (reloc->offset + sizeof(uint32_t)) >> PAGE_SHIFT));
369 		}
370 
371 		clflush_write32(vaddr + page_offset, upper_32_bits(delta));
372 	}
373 
374 	kunmap_atomic(vaddr);
375 
376 	return 0;
377 }
378 
379 static int
380 i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj,
381 				   struct eb_vmas *eb,
382 				   struct drm_i915_gem_relocation_entry *reloc)
383 {
384 	struct drm_device *dev = obj->base.dev;
385 	struct drm_gem_object *target_obj;
386 	struct drm_i915_gem_object *target_i915_obj;
387 	struct i915_vma *target_vma;
388 	uint64_t target_offset;
389 	int ret;
390 
391 	/* we've already hold a reference to all valid objects */
392 	target_vma = eb_get_vma(eb, reloc->target_handle);
393 	if (unlikely(target_vma == NULL))
394 		return -ENOENT;
395 	target_i915_obj = target_vma->obj;
396 	target_obj = &target_vma->obj->base;
397 
398 	target_offset = target_vma->node.start;
399 
400 	/* Sandybridge PPGTT errata: We need a global gtt mapping for MI and
401 	 * pipe_control writes because the gpu doesn't properly redirect them
402 	 * through the ppgtt for non_secure batchbuffers. */
403 	if (unlikely(IS_GEN6(dev) &&
404 	    reloc->write_domain == I915_GEM_DOMAIN_INSTRUCTION)) {
405 		ret = i915_vma_bind(target_vma, target_i915_obj->cache_level,
406 				    PIN_GLOBAL);
407 		if (WARN_ONCE(ret, "Unexpected failure to bind target VMA!"))
408 			return ret;
409 	}
410 
411 	/* Validate that the target is in a valid r/w GPU domain */
412 	if (unlikely(reloc->write_domain & (reloc->write_domain - 1))) {
413 		DRM_DEBUG("reloc with multiple write domains: "
414 			  "obj %p target %d offset %d "
415 			  "read %08x write %08x",
416 			  obj, reloc->target_handle,
417 			  (int) reloc->offset,
418 			  reloc->read_domains,
419 			  reloc->write_domain);
420 		return -EINVAL;
421 	}
422 	if (unlikely((reloc->write_domain | reloc->read_domains)
423 		     & ~I915_GEM_GPU_DOMAINS)) {
424 		DRM_DEBUG("reloc with read/write non-GPU domains: "
425 			  "obj %p target %d offset %d "
426 			  "read %08x write %08x",
427 			  obj, reloc->target_handle,
428 			  (int) reloc->offset,
429 			  reloc->read_domains,
430 			  reloc->write_domain);
431 		return -EINVAL;
432 	}
433 
434 	target_obj->pending_read_domains |= reloc->read_domains;
435 	target_obj->pending_write_domain |= reloc->write_domain;
436 
437 	/* If the relocation already has the right value in it, no
438 	 * more work needs to be done.
439 	 */
440 	if (target_offset == reloc->presumed_offset)
441 		return 0;
442 
443 	/* Check that the relocation address is valid... */
444 	if (unlikely(reloc->offset >
445 		obj->base.size - (INTEL_INFO(dev)->gen >= 8 ? 8 : 4))) {
446 		DRM_DEBUG("Relocation beyond object bounds: "
447 			  "obj %p target %d offset %d size %d.\n",
448 			  obj, reloc->target_handle,
449 			  (int) reloc->offset,
450 			  (int) obj->base.size);
451 		return -EINVAL;
452 	}
453 	if (unlikely(reloc->offset & 3)) {
454 		DRM_DEBUG("Relocation not 4-byte aligned: "
455 			  "obj %p target %d offset %d.\n",
456 			  obj, reloc->target_handle,
457 			  (int) reloc->offset);
458 		return -EINVAL;
459 	}
460 
461 	/* We can't wait for rendering with pagefaults disabled */
462 	if (obj->active && (curthread->td_flags & TDF_NOFAULT))
463 		return -EFAULT;
464 
465 	if (use_cpu_reloc(obj))
466 		ret = relocate_entry_cpu(obj, reloc, target_offset);
467 	else if (obj->map_and_fenceable)
468 		ret = relocate_entry_gtt(obj, reloc, target_offset);
469 	else if (cpu_has_clflush)
470 		ret = relocate_entry_clflush(obj, reloc, target_offset);
471 	else {
472 		WARN_ONCE(1, "Impossible case in relocation handling\n");
473 		ret = -ENODEV;
474 	}
475 
476 	if (ret)
477 		return ret;
478 
479 	/* and update the user's relocation entry */
480 	reloc->presumed_offset = target_offset;
481 
482 	return 0;
483 }
484 
485 static int
486 i915_gem_execbuffer_relocate_vma(struct i915_vma *vma,
487 				 struct eb_vmas *eb)
488 {
489 #define N_RELOC(x) ((x) / sizeof(struct drm_i915_gem_relocation_entry))
490 	struct drm_i915_gem_relocation_entry stack_reloc[N_RELOC(512)];
491 	struct drm_i915_gem_relocation_entry __user *user_relocs;
492 	struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
493 	int remain, ret;
494 
495 	user_relocs = to_user_ptr(entry->relocs_ptr);
496 
497 	remain = entry->relocation_count;
498 	while (remain) {
499 		struct drm_i915_gem_relocation_entry *r = stack_reloc;
500 		int count = remain;
501 		if (count > ARRAY_SIZE(stack_reloc))
502 			count = ARRAY_SIZE(stack_reloc);
503 		remain -= count;
504 
505 		if (__copy_from_user_inatomic(r, user_relocs, count*sizeof(r[0])))
506 			return -EFAULT;
507 
508 		do {
509 			u64 offset = r->presumed_offset;
510 
511 			ret = i915_gem_execbuffer_relocate_entry(vma->obj, eb, r);
512 			if (ret)
513 				return ret;
514 
515 			if (r->presumed_offset != offset &&
516 			    __copy_to_user_inatomic(&user_relocs->presumed_offset,
517 						    &r->presumed_offset,
518 						    sizeof(r->presumed_offset))) {
519 				return -EFAULT;
520 			}
521 
522 			user_relocs++;
523 			r++;
524 		} while (--count);
525 	}
526 
527 	return 0;
528 #undef N_RELOC
529 }
530 
531 static int
532 i915_gem_execbuffer_relocate_vma_slow(struct i915_vma *vma,
533 				      struct eb_vmas *eb,
534 				      struct drm_i915_gem_relocation_entry *relocs)
535 {
536 	const struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
537 	int i, ret;
538 
539 	for (i = 0; i < entry->relocation_count; i++) {
540 		ret = i915_gem_execbuffer_relocate_entry(vma->obj, eb, &relocs[i]);
541 		if (ret)
542 			return ret;
543 	}
544 
545 	return 0;
546 }
547 
548 static int
549 i915_gem_execbuffer_relocate(struct eb_vmas *eb)
550 {
551 	struct i915_vma *vma;
552 	int ret = 0;
553 
554 	/* This is the fast path and we cannot handle a pagefault whilst
555 	 * holding the struct mutex lest the user pass in the relocations
556 	 * contained within a mmaped bo. For in such a case we, the page
557 	 * fault handler would call i915_gem_fault() and we would try to
558 	 * acquire the struct mutex again. Obviously this is bad and so
559 	 * lockdep complains vehemently.
560 	 */
561 	pagefault_disable();
562 	list_for_each_entry(vma, &eb->vmas, exec_list) {
563 		ret = i915_gem_execbuffer_relocate_vma(vma, eb);
564 		if (ret)
565 			break;
566 	}
567 	pagefault_enable();
568 
569 	return ret;
570 }
571 
572 static bool only_mappable_for_reloc(unsigned int flags)
573 {
574 	return (flags & (EXEC_OBJECT_NEEDS_FENCE | __EXEC_OBJECT_NEEDS_MAP)) ==
575 		__EXEC_OBJECT_NEEDS_MAP;
576 }
577 
578 static int
579 i915_gem_execbuffer_reserve_vma(struct i915_vma *vma,
580 				struct intel_engine_cs *ring,
581 				bool *need_reloc)
582 {
583 	struct drm_i915_gem_object *obj = vma->obj;
584 	struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
585 	uint64_t flags;
586 	int ret;
587 
588 	flags = PIN_USER;
589 	if (entry->flags & EXEC_OBJECT_NEEDS_GTT)
590 		flags |= PIN_GLOBAL;
591 
592 	if (!drm_mm_node_allocated(&vma->node)) {
593 		if (entry->flags & __EXEC_OBJECT_NEEDS_MAP)
594 			flags |= PIN_GLOBAL | PIN_MAPPABLE;
595 		if (entry->flags & __EXEC_OBJECT_NEEDS_BIAS)
596 			flags |= BATCH_OFFSET_BIAS | PIN_OFFSET_BIAS;
597 	}
598 
599 	ret = i915_gem_object_pin(obj, vma->vm, entry->alignment, flags);
600 	if ((ret == -ENOSPC  || ret == -E2BIG) &&
601 	    only_mappable_for_reloc(entry->flags))
602 		ret = i915_gem_object_pin(obj, vma->vm,
603 					  entry->alignment,
604 					  flags & ~PIN_MAPPABLE);
605 	if (ret)
606 		return ret;
607 
608 	entry->flags |= __EXEC_OBJECT_HAS_PIN;
609 
610 	if (entry->flags & EXEC_OBJECT_NEEDS_FENCE) {
611 		ret = i915_gem_object_get_fence(obj);
612 		if (ret)
613 			return ret;
614 
615 		if (i915_gem_object_pin_fence(obj))
616 			entry->flags |= __EXEC_OBJECT_HAS_FENCE;
617 	}
618 
619 	if (entry->offset != vma->node.start) {
620 		entry->offset = vma->node.start;
621 		*need_reloc = true;
622 	}
623 
624 	if (entry->flags & EXEC_OBJECT_WRITE) {
625 		obj->base.pending_read_domains = I915_GEM_DOMAIN_RENDER;
626 		obj->base.pending_write_domain = I915_GEM_DOMAIN_RENDER;
627 	}
628 
629 	return 0;
630 }
631 
632 static bool
633 need_reloc_mappable(struct i915_vma *vma)
634 {
635 	struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
636 
637 	if (entry->relocation_count == 0)
638 		return false;
639 
640 	if (!i915_is_ggtt(vma->vm))
641 		return false;
642 
643 	/* See also use_cpu_reloc() */
644 	if (HAS_LLC(vma->obj->base.dev))
645 		return false;
646 
647 	if (vma->obj->base.write_domain == I915_GEM_DOMAIN_CPU)
648 		return false;
649 
650 	return true;
651 }
652 
653 static bool
654 eb_vma_misplaced(struct i915_vma *vma)
655 {
656 	struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
657 	struct drm_i915_gem_object *obj = vma->obj;
658 
659 	WARN_ON(entry->flags & __EXEC_OBJECT_NEEDS_MAP &&
660 	       !i915_is_ggtt(vma->vm));
661 
662 	if (entry->alignment &&
663 	    vma->node.start & (entry->alignment - 1))
664 		return true;
665 
666 	if (entry->flags & __EXEC_OBJECT_NEEDS_BIAS &&
667 	    vma->node.start < BATCH_OFFSET_BIAS)
668 		return true;
669 
670 	/* avoid costly ping-pong once a batch bo ended up non-mappable */
671 	if (entry->flags & __EXEC_OBJECT_NEEDS_MAP && !obj->map_and_fenceable)
672 		return !only_mappable_for_reloc(entry->flags);
673 
674 	return false;
675 }
676 
677 static int
678 i915_gem_execbuffer_reserve(struct intel_engine_cs *ring,
679 			    struct list_head *vmas,
680 			    struct intel_context *ctx,
681 			    bool *need_relocs)
682 {
683 	struct drm_i915_gem_object *obj;
684 	struct i915_vma *vma;
685 	struct i915_address_space *vm;
686 	struct list_head ordered_vmas;
687 	bool has_fenced_gpu_access = INTEL_INFO(ring->dev)->gen < 4;
688 	int retry;
689 
690 	i915_gem_retire_requests_ring(ring);
691 
692 	vm = list_first_entry(vmas, struct i915_vma, exec_list)->vm;
693 
694 	INIT_LIST_HEAD(&ordered_vmas);
695 	while (!list_empty(vmas)) {
696 		struct drm_i915_gem_exec_object2 *entry;
697 		bool need_fence, need_mappable;
698 
699 		vma = list_first_entry(vmas, struct i915_vma, exec_list);
700 		obj = vma->obj;
701 		entry = vma->exec_entry;
702 
703 		if (ctx->flags & CONTEXT_NO_ZEROMAP)
704 			entry->flags |= __EXEC_OBJECT_NEEDS_BIAS;
705 
706 		if (!has_fenced_gpu_access)
707 			entry->flags &= ~EXEC_OBJECT_NEEDS_FENCE;
708 		need_fence =
709 			entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
710 			obj->tiling_mode != I915_TILING_NONE;
711 		need_mappable = need_fence || need_reloc_mappable(vma);
712 
713 		if (need_mappable) {
714 			entry->flags |= __EXEC_OBJECT_NEEDS_MAP;
715 			list_move(&vma->exec_list, &ordered_vmas);
716 		} else
717 			list_move_tail(&vma->exec_list, &ordered_vmas);
718 
719 		obj->base.pending_read_domains = I915_GEM_GPU_DOMAINS & ~I915_GEM_DOMAIN_COMMAND;
720 		obj->base.pending_write_domain = 0;
721 	}
722 	list_splice(&ordered_vmas, vmas);
723 
724 	/* Attempt to pin all of the buffers into the GTT.
725 	 * This is done in 3 phases:
726 	 *
727 	 * 1a. Unbind all objects that do not match the GTT constraints for
728 	 *     the execbuffer (fenceable, mappable, alignment etc).
729 	 * 1b. Increment pin count for already bound objects.
730 	 * 2.  Bind new objects.
731 	 * 3.  Decrement pin count.
732 	 *
733 	 * This avoid unnecessary unbinding of later objects in order to make
734 	 * room for the earlier objects *unless* we need to defragment.
735 	 */
736 	retry = 0;
737 	do {
738 		int ret = 0;
739 
740 		/* Unbind any ill-fitting objects or pin. */
741 		list_for_each_entry(vma, vmas, exec_list) {
742 			if (!drm_mm_node_allocated(&vma->node))
743 				continue;
744 
745 			if (eb_vma_misplaced(vma))
746 				ret = i915_vma_unbind(vma);
747 			else
748 				ret = i915_gem_execbuffer_reserve_vma(vma, ring, need_relocs);
749 			if (ret)
750 				goto err;
751 		}
752 
753 		/* Bind fresh objects */
754 		list_for_each_entry(vma, vmas, exec_list) {
755 			if (drm_mm_node_allocated(&vma->node))
756 				continue;
757 
758 			ret = i915_gem_execbuffer_reserve_vma(vma, ring, need_relocs);
759 			if (ret)
760 				goto err;
761 		}
762 
763 err:
764 		if (ret != -ENOSPC || retry++)
765 			return ret;
766 
767 		/* Decrement pin count for bound objects */
768 		list_for_each_entry(vma, vmas, exec_list)
769 			i915_gem_execbuffer_unreserve_vma(vma);
770 
771 		ret = i915_gem_evict_vm(vm, true);
772 		if (ret)
773 			return ret;
774 	} while (1);
775 }
776 
777 static int
778 i915_gem_execbuffer_relocate_slow(struct drm_device *dev,
779 				  struct drm_i915_gem_execbuffer2 *args,
780 				  struct drm_file *file,
781 				  struct intel_engine_cs *ring,
782 				  struct eb_vmas *eb,
783 				  struct drm_i915_gem_exec_object2 *exec,
784 				  struct intel_context *ctx)
785 {
786 	struct drm_i915_gem_relocation_entry *reloc;
787 	struct i915_address_space *vm;
788 	struct i915_vma *vma;
789 	bool need_relocs;
790 	int *reloc_offset;
791 	int i, total, ret;
792 	unsigned count = args->buffer_count;
793 
794 	vm = list_first_entry(&eb->vmas, struct i915_vma, exec_list)->vm;
795 
796 	/* We may process another execbuffer during the unlock... */
797 	while (!list_empty(&eb->vmas)) {
798 		vma = list_first_entry(&eb->vmas, struct i915_vma, exec_list);
799 		list_del_init(&vma->exec_list);
800 		i915_gem_execbuffer_unreserve_vma(vma);
801 		drm_gem_object_unreference(&vma->obj->base);
802 	}
803 
804 	mutex_unlock(&dev->struct_mutex);
805 
806 	total = 0;
807 	for (i = 0; i < count; i++)
808 		total += exec[i].relocation_count;
809 
810 	reloc_offset = drm_malloc_ab(count, sizeof(*reloc_offset));
811 	reloc = drm_malloc_ab(total, sizeof(*reloc));
812 	if (reloc == NULL || reloc_offset == NULL) {
813 		drm_free_large(reloc);
814 		drm_free_large(reloc_offset);
815 		mutex_lock(&dev->struct_mutex);
816 		return -ENOMEM;
817 	}
818 
819 	total = 0;
820 	for (i = 0; i < count; i++) {
821 		struct drm_i915_gem_relocation_entry __user *user_relocs;
822 		u64 invalid_offset = (u64)-1;
823 		int j;
824 
825 		user_relocs = to_user_ptr(exec[i].relocs_ptr);
826 
827 		if (copy_from_user(reloc+total, user_relocs,
828 				   exec[i].relocation_count * sizeof(*reloc))) {
829 			ret = -EFAULT;
830 			mutex_lock(&dev->struct_mutex);
831 			goto err;
832 		}
833 
834 		/* As we do not update the known relocation offsets after
835 		 * relocating (due to the complexities in lock handling),
836 		 * we need to mark them as invalid now so that we force the
837 		 * relocation processing next time. Just in case the target
838 		 * object is evicted and then rebound into its old
839 		 * presumed_offset before the next execbuffer - if that
840 		 * happened we would make the mistake of assuming that the
841 		 * relocations were valid.
842 		 */
843 		for (j = 0; j < exec[i].relocation_count; j++) {
844 			if (__copy_to_user(&user_relocs[j].presumed_offset,
845 					   &invalid_offset,
846 					   sizeof(invalid_offset))) {
847 				ret = -EFAULT;
848 				mutex_lock(&dev->struct_mutex);
849 				goto err;
850 			}
851 		}
852 
853 		reloc_offset[i] = total;
854 		total += exec[i].relocation_count;
855 	}
856 
857 	ret = i915_mutex_lock_interruptible(dev);
858 	if (ret) {
859 		mutex_lock(&dev->struct_mutex);
860 		goto err;
861 	}
862 
863 	/* reacquire the objects */
864 	eb_reset(eb);
865 	ret = eb_lookup_vmas(eb, exec, args, vm, file);
866 	if (ret)
867 		goto err;
868 
869 	need_relocs = (args->flags & I915_EXEC_NO_RELOC) == 0;
870 	ret = i915_gem_execbuffer_reserve(ring, &eb->vmas, ctx, &need_relocs);
871 	if (ret)
872 		goto err;
873 
874 	list_for_each_entry(vma, &eb->vmas, exec_list) {
875 		int offset = vma->exec_entry - exec;
876 		ret = i915_gem_execbuffer_relocate_vma_slow(vma, eb,
877 							    reloc + reloc_offset[offset]);
878 		if (ret)
879 			goto err;
880 	}
881 
882 	/* Leave the user relocations as are, this is the painfully slow path,
883 	 * and we want to avoid the complication of dropping the lock whilst
884 	 * having buffers reserved in the aperture and so causing spurious
885 	 * ENOSPC for random operations.
886 	 */
887 
888 err:
889 	drm_free_large(reloc);
890 	drm_free_large(reloc_offset);
891 	return ret;
892 }
893 
894 static int
895 i915_gem_execbuffer_move_to_gpu(struct drm_i915_gem_request *req,
896 				struct list_head *vmas)
897 {
898 	const unsigned other_rings = ~intel_ring_flag(req->ring);
899 	struct i915_vma *vma;
900 	uint32_t flush_domains = 0;
901 	bool flush_chipset = false;
902 	int ret;
903 
904 	list_for_each_entry(vma, vmas, exec_list) {
905 		struct drm_i915_gem_object *obj = vma->obj;
906 
907 		if (obj->active & other_rings) {
908 			ret = i915_gem_object_sync(obj, req->ring, &req);
909 			if (ret)
910 				return ret;
911 		}
912 
913 		if (obj->base.write_domain & I915_GEM_DOMAIN_CPU)
914 			flush_chipset |= i915_gem_clflush_object(obj, false);
915 
916 		flush_domains |= obj->base.write_domain;
917 	}
918 
919 	if (flush_chipset)
920 		i915_gem_chipset_flush(req->ring->dev);
921 
922 	if (flush_domains & I915_GEM_DOMAIN_GTT)
923 		wmb();
924 
925 	/* Unconditionally invalidate gpu caches and ensure that we do flush
926 	 * any residual writes from the previous batch.
927 	 */
928 	return intel_ring_invalidate_all_caches(req);
929 }
930 
931 static bool
932 i915_gem_check_execbuffer(struct drm_i915_gem_execbuffer2 *exec)
933 {
934 	if (exec->flags & __I915_EXEC_UNKNOWN_FLAGS)
935 		return false;
936 
937 	return ((exec->batch_start_offset | exec->batch_len) & 0x7) == 0;
938 }
939 
940 static int
941 validate_exec_list(struct drm_device *dev,
942 		   struct drm_i915_gem_exec_object2 *exec,
943 		   int count)
944 {
945 	unsigned relocs_total = 0;
946 	unsigned relocs_max = UINT_MAX / sizeof(struct drm_i915_gem_relocation_entry);
947 	unsigned invalid_flags;
948 	int i;
949 
950 	invalid_flags = __EXEC_OBJECT_UNKNOWN_FLAGS;
951 	if (USES_FULL_PPGTT(dev))
952 		invalid_flags |= EXEC_OBJECT_NEEDS_GTT;
953 
954 	for (i = 0; i < count; i++) {
955 		char __user *ptr = to_user_ptr(exec[i].relocs_ptr);
956 		int length; /* limited by fault_in_pages_readable() */
957 
958 		if (exec[i].flags & invalid_flags)
959 			return -EINVAL;
960 
961 		if (exec[i].alignment && !is_power_of_2(exec[i].alignment))
962 			return -EINVAL;
963 
964 		/* First check for malicious input causing overflow in
965 		 * the worst case where we need to allocate the entire
966 		 * relocation tree as a single array.
967 		 */
968 		if (exec[i].relocation_count > relocs_max - relocs_total)
969 			return -EINVAL;
970 		relocs_total += exec[i].relocation_count;
971 
972 		length = exec[i].relocation_count *
973 			sizeof(struct drm_i915_gem_relocation_entry);
974 		/*
975 		 * We must check that the entire relocation array is safe
976 		 * to read, but since we may need to update the presumed
977 		 * offsets during execution, check for full write access.
978 		 */
979 #if 0
980 		if (!access_ok(VERIFY_WRITE, ptr, length))
981 			return -EFAULT;
982 #endif
983 
984 		if (likely(!i915.prefault_disable)) {
985 			if (fault_in_multipages_readable(ptr, length))
986 				return -EFAULT;
987 		}
988 	}
989 
990 	return 0;
991 }
992 
993 static struct intel_context *
994 i915_gem_validate_context(struct drm_device *dev, struct drm_file *file,
995 			  struct intel_engine_cs *ring, const u32 ctx_id)
996 {
997 	struct intel_context *ctx = NULL;
998 	struct i915_ctx_hang_stats *hs;
999 
1000 	if (ring->id != RCS && ctx_id != DEFAULT_CONTEXT_HANDLE)
1001 		return ERR_PTR(-EINVAL);
1002 
1003 	ctx = i915_gem_context_get(file->driver_priv, ctx_id);
1004 	if (IS_ERR(ctx))
1005 		return ctx;
1006 
1007 	hs = &ctx->hang_stats;
1008 	if (hs->banned) {
1009 		DRM_DEBUG("Context %u tried to submit while banned\n", ctx_id);
1010 		return ERR_PTR(-EIO);
1011 	}
1012 
1013 	if (i915.enable_execlists && !ctx->engine[ring->id].state) {
1014 		int ret = intel_lr_context_deferred_create(ctx, ring);
1015 		if (ret) {
1016 			DRM_DEBUG("Could not create LRC %u: %d\n", ctx_id, ret);
1017 			return ERR_PTR(ret);
1018 		}
1019 	}
1020 
1021 	return ctx;
1022 }
1023 
1024 void
1025 i915_gem_execbuffer_move_to_active(struct list_head *vmas,
1026 				   struct drm_i915_gem_request *req)
1027 {
1028 	struct intel_engine_cs *ring = i915_gem_request_get_ring(req);
1029 	struct i915_vma *vma;
1030 
1031 	list_for_each_entry(vma, vmas, exec_list) {
1032 		struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
1033 		struct drm_i915_gem_object *obj = vma->obj;
1034 		u32 old_read = obj->base.read_domains;
1035 		u32 old_write = obj->base.write_domain;
1036 
1037 		obj->dirty = 1; /* be paranoid  */
1038 		obj->base.write_domain = obj->base.pending_write_domain;
1039 		if (obj->base.write_domain == 0)
1040 			obj->base.pending_read_domains |= obj->base.read_domains;
1041 		obj->base.read_domains = obj->base.pending_read_domains;
1042 
1043 		i915_vma_move_to_active(vma, req);
1044 		if (obj->base.write_domain) {
1045 			i915_gem_request_assign(&obj->last_write_req, req);
1046 
1047 			intel_fb_obj_invalidate(obj, ORIGIN_CS);
1048 
1049 			/* update for the implicit flush after a batch */
1050 			obj->base.write_domain &= ~I915_GEM_GPU_DOMAINS;
1051 		}
1052 		if (entry->flags & EXEC_OBJECT_NEEDS_FENCE) {
1053 			i915_gem_request_assign(&obj->last_fenced_req, req);
1054 			if (entry->flags & __EXEC_OBJECT_HAS_FENCE) {
1055 				struct drm_i915_private *dev_priv = to_i915(ring->dev);
1056 				list_move_tail(&dev_priv->fence_regs[obj->fence_reg].lru_list,
1057 					       &dev_priv->mm.fence_list);
1058 			}
1059 		}
1060 
1061 		trace_i915_gem_object_change_domain(obj, old_read, old_write);
1062 	}
1063 }
1064 
1065 void
1066 i915_gem_execbuffer_retire_commands(struct i915_execbuffer_params *params)
1067 {
1068 	/* Unconditionally force add_request to emit a full flush. */
1069 	params->ring->gpu_caches_dirty = true;
1070 
1071 	/* Add a breadcrumb for the completion of the batch buffer */
1072 	__i915_add_request(params->request, params->batch_obj, true);
1073 }
1074 
1075 static int
1076 i915_reset_gen7_sol_offsets(struct drm_device *dev,
1077 			    struct drm_i915_gem_request *req)
1078 {
1079 	struct intel_engine_cs *ring = req->ring;
1080 	struct drm_i915_private *dev_priv = dev->dev_private;
1081 	int ret, i;
1082 
1083 	if (!IS_GEN7(dev) || ring != &dev_priv->ring[RCS]) {
1084 		DRM_DEBUG("sol reset is gen7/rcs only\n");
1085 		return -EINVAL;
1086 	}
1087 
1088 	ret = intel_ring_begin(req, 4 * 3);
1089 	if (ret)
1090 		return ret;
1091 
1092 	for (i = 0; i < 4; i++) {
1093 		intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
1094 		intel_ring_emit(ring, GEN7_SO_WRITE_OFFSET(i));
1095 		intel_ring_emit(ring, 0);
1096 	}
1097 
1098 	intel_ring_advance(ring);
1099 
1100 	return 0;
1101 }
1102 
1103 static int
1104 i915_emit_box(struct drm_i915_gem_request *req,
1105 	      struct drm_clip_rect *box,
1106 	      int DR1, int DR4)
1107 {
1108 	struct intel_engine_cs *ring = req->ring;
1109 	int ret;
1110 
1111 	if (box->y2 <= box->y1 || box->x2 <= box->x1 ||
1112 	    box->y2 <= 0 || box->x2 <= 0) {
1113 		DRM_ERROR("Bad box %d,%d..%d,%d\n",
1114 			  box->x1, box->y1, box->x2, box->y2);
1115 		return -EINVAL;
1116 	}
1117 
1118 	if (INTEL_INFO(ring->dev)->gen >= 4) {
1119 		ret = intel_ring_begin(req, 4);
1120 		if (ret)
1121 			return ret;
1122 
1123 		intel_ring_emit(ring, GFX_OP_DRAWRECT_INFO_I965);
1124 		intel_ring_emit(ring, (box->x1 & 0xffff) | box->y1 << 16);
1125 		intel_ring_emit(ring, ((box->x2 - 1) & 0xffff) | (box->y2 - 1) << 16);
1126 		intel_ring_emit(ring, DR4);
1127 	} else {
1128 		ret = intel_ring_begin(req, 6);
1129 		if (ret)
1130 			return ret;
1131 
1132 		intel_ring_emit(ring, GFX_OP_DRAWRECT_INFO);
1133 		intel_ring_emit(ring, DR1);
1134 		intel_ring_emit(ring, (box->x1 & 0xffff) | box->y1 << 16);
1135 		intel_ring_emit(ring, ((box->x2 - 1) & 0xffff) | (box->y2 - 1) << 16);
1136 		intel_ring_emit(ring, DR4);
1137 		intel_ring_emit(ring, 0);
1138 	}
1139 	intel_ring_advance(ring);
1140 
1141 	return 0;
1142 }
1143 
1144 static struct drm_i915_gem_object*
1145 i915_gem_execbuffer_parse(struct intel_engine_cs *ring,
1146 			  struct drm_i915_gem_exec_object2 *shadow_exec_entry,
1147 			  struct eb_vmas *eb,
1148 			  struct drm_i915_gem_object *batch_obj,
1149 			  u32 batch_start_offset,
1150 			  u32 batch_len,
1151 			  bool is_master)
1152 {
1153 	struct drm_i915_gem_object *shadow_batch_obj;
1154 	struct i915_vma *vma;
1155 	int ret;
1156 
1157 	shadow_batch_obj = i915_gem_batch_pool_get(&ring->batch_pool,
1158 						   PAGE_ALIGN(batch_len));
1159 	if (IS_ERR(shadow_batch_obj))
1160 		return shadow_batch_obj;
1161 
1162 	ret = i915_parse_cmds(ring,
1163 			      batch_obj,
1164 			      shadow_batch_obj,
1165 			      batch_start_offset,
1166 			      batch_len,
1167 			      is_master);
1168 	if (ret)
1169 		goto err;
1170 
1171 	ret = i915_gem_obj_ggtt_pin(shadow_batch_obj, 0, 0);
1172 	if (ret)
1173 		goto err;
1174 
1175 	i915_gem_object_unpin_pages(shadow_batch_obj);
1176 
1177 	memset(shadow_exec_entry, 0, sizeof(*shadow_exec_entry));
1178 
1179 	vma = i915_gem_obj_to_ggtt(shadow_batch_obj);
1180 	vma->exec_entry = shadow_exec_entry;
1181 	vma->exec_entry->flags = __EXEC_OBJECT_HAS_PIN;
1182 	drm_gem_object_reference(&shadow_batch_obj->base);
1183 	list_add_tail(&vma->exec_list, &eb->vmas);
1184 
1185 	shadow_batch_obj->base.pending_read_domains = I915_GEM_DOMAIN_COMMAND;
1186 
1187 	return shadow_batch_obj;
1188 
1189 err:
1190 	i915_gem_object_unpin_pages(shadow_batch_obj);
1191 	if (ret == -EACCES) /* unhandled chained batch */
1192 		return batch_obj;
1193 	else
1194 		return ERR_PTR(ret);
1195 }
1196 
1197 int
1198 i915_gem_ringbuffer_submission(struct i915_execbuffer_params *params,
1199 			       struct drm_i915_gem_execbuffer2 *args,
1200 			       struct list_head *vmas)
1201 {
1202 	struct drm_clip_rect *cliprects = NULL;
1203 	struct drm_device *dev = params->dev;
1204 	struct intel_engine_cs *ring = params->ring;
1205 	struct drm_i915_private *dev_priv = dev->dev_private;
1206 	u64 exec_start, exec_len;
1207 	int instp_mode;
1208 	u32 instp_mask;
1209 	int i, ret = 0;
1210 
1211 	if (args->num_cliprects != 0) {
1212 		if (ring != &dev_priv->ring[RCS]) {
1213 			DRM_DEBUG("clip rectangles are only valid with the render ring\n");
1214 			return -EINVAL;
1215 		}
1216 
1217 		if (INTEL_INFO(dev)->gen >= 5) {
1218 			DRM_DEBUG("clip rectangles are only valid on pre-gen5\n");
1219 			return -EINVAL;
1220 		}
1221 
1222 		if (args->num_cliprects > UINT_MAX / sizeof(*cliprects)) {
1223 			DRM_DEBUG("execbuf with %u cliprects\n",
1224 				  args->num_cliprects);
1225 			return -EINVAL;
1226 		}
1227 
1228 		cliprects = kcalloc(args->num_cliprects,
1229 				    sizeof(*cliprects),
1230 				    GFP_KERNEL);
1231 		if (cliprects == NULL) {
1232 			ret = -ENOMEM;
1233 			goto error;
1234 		}
1235 
1236 		if (copy_from_user(cliprects,
1237 				   to_user_ptr(args->cliprects_ptr),
1238 				   sizeof(*cliprects)*args->num_cliprects)) {
1239 			ret = -EFAULT;
1240 			goto error;
1241 		}
1242 	} else {
1243 		if (args->DR4 == 0xffffffff) {
1244 			DRM_DEBUG("UXA submitting garbage DR4, fixing up\n");
1245 			args->DR4 = 0;
1246 		}
1247 
1248 		if (args->DR1 || args->DR4 || args->cliprects_ptr) {
1249 			DRM_DEBUG("0 cliprects but dirt in cliprects fields\n");
1250 			return -EINVAL;
1251 		}
1252 	}
1253 
1254 	ret = i915_gem_execbuffer_move_to_gpu(params->request, vmas);
1255 	if (ret)
1256 		goto error;
1257 
1258 	ret = i915_switch_context(params->request);
1259 	if (ret)
1260 		goto error;
1261 
1262 	WARN(params->ctx->ppgtt && params->ctx->ppgtt->pd_dirty_rings & (1<<ring->id),
1263 	     "%s didn't clear reload\n", ring->name);
1264 
1265 	instp_mode = args->flags & I915_EXEC_CONSTANTS_MASK;
1266 	instp_mask = I915_EXEC_CONSTANTS_MASK;
1267 	switch (instp_mode) {
1268 	case I915_EXEC_CONSTANTS_REL_GENERAL:
1269 	case I915_EXEC_CONSTANTS_ABSOLUTE:
1270 	case I915_EXEC_CONSTANTS_REL_SURFACE:
1271 		if (instp_mode != 0 && ring != &dev_priv->ring[RCS]) {
1272 			DRM_DEBUG("non-0 rel constants mode on non-RCS\n");
1273 			ret = -EINVAL;
1274 			goto error;
1275 		}
1276 
1277 		if (instp_mode != dev_priv->relative_constants_mode) {
1278 			if (INTEL_INFO(dev)->gen < 4) {
1279 				DRM_DEBUG("no rel constants on pre-gen4\n");
1280 				ret = -EINVAL;
1281 				goto error;
1282 			}
1283 
1284 			if (INTEL_INFO(dev)->gen > 5 &&
1285 			    instp_mode == I915_EXEC_CONSTANTS_REL_SURFACE) {
1286 				DRM_DEBUG("rel surface constants mode invalid on gen5+\n");
1287 				ret = -EINVAL;
1288 				goto error;
1289 			}
1290 
1291 			/* The HW changed the meaning on this bit on gen6 */
1292 			if (INTEL_INFO(dev)->gen >= 6)
1293 				instp_mask &= ~I915_EXEC_CONSTANTS_REL_SURFACE;
1294 		}
1295 		break;
1296 	default:
1297 		DRM_DEBUG("execbuf with unknown constants: %d\n", instp_mode);
1298 		ret = -EINVAL;
1299 		goto error;
1300 	}
1301 
1302 	if (ring == &dev_priv->ring[RCS] &&
1303 			instp_mode != dev_priv->relative_constants_mode) {
1304 		ret = intel_ring_begin(params->request, 4);
1305 		if (ret)
1306 			goto error;
1307 
1308 		intel_ring_emit(ring, MI_NOOP);
1309 		intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
1310 		intel_ring_emit(ring, INSTPM);
1311 		intel_ring_emit(ring, instp_mask << 16 | instp_mode);
1312 		intel_ring_advance(ring);
1313 
1314 		dev_priv->relative_constants_mode = instp_mode;
1315 	}
1316 
1317 	if (args->flags & I915_EXEC_GEN7_SOL_RESET) {
1318 		ret = i915_reset_gen7_sol_offsets(dev, params->request);
1319 		if (ret)
1320 			goto error;
1321 	}
1322 
1323 	exec_len   = args->batch_len;
1324 	exec_start = params->batch_obj_vm_offset +
1325 		     params->args_batch_start_offset;
1326 
1327 	if (cliprects) {
1328 		for (i = 0; i < args->num_cliprects; i++) {
1329 			ret = i915_emit_box(params->request, &cliprects[i],
1330 					    args->DR1, args->DR4);
1331 			if (ret)
1332 				goto error;
1333 
1334 			ret = ring->dispatch_execbuffer(params->request,
1335 							exec_start, exec_len,
1336 							params->dispatch_flags);
1337 			if (ret)
1338 				goto error;
1339 		}
1340 	} else {
1341 		ret = ring->dispatch_execbuffer(params->request,
1342 						exec_start, exec_len,
1343 						params->dispatch_flags);
1344 		if (ret)
1345 			return ret;
1346 	}
1347 
1348 	trace_i915_gem_ring_dispatch(params->request, params->dispatch_flags);
1349 
1350 	i915_gem_execbuffer_move_to_active(vmas, params->request);
1351 	i915_gem_execbuffer_retire_commands(params);
1352 
1353 error:
1354 	kfree(cliprects);
1355 	return ret;
1356 }
1357 
1358 /**
1359  * Find one BSD ring to dispatch the corresponding BSD command.
1360  * The Ring ID is returned.
1361  */
1362 static int gen8_dispatch_bsd_ring(struct drm_device *dev,
1363 				  struct drm_file *file)
1364 {
1365 	struct drm_i915_private *dev_priv = dev->dev_private;
1366 	struct drm_i915_file_private *file_priv = file->driver_priv;
1367 
1368 	/* Check whether the file_priv is using one ring */
1369 	if (file_priv->bsd_ring)
1370 		return file_priv->bsd_ring->id;
1371 	else {
1372 		/* If no, use the ping-pong mechanism to select one ring */
1373 		int ring_id;
1374 
1375 		mutex_lock(&dev->struct_mutex);
1376 		if (dev_priv->mm.bsd_ring_dispatch_index == 0) {
1377 			ring_id = VCS;
1378 			dev_priv->mm.bsd_ring_dispatch_index = 1;
1379 		} else {
1380 			ring_id = VCS2;
1381 			dev_priv->mm.bsd_ring_dispatch_index = 0;
1382 		}
1383 		file_priv->bsd_ring = &dev_priv->ring[ring_id];
1384 		mutex_unlock(&dev->struct_mutex);
1385 		return ring_id;
1386 	}
1387 }
1388 
1389 static struct drm_i915_gem_object *
1390 eb_get_batch(struct eb_vmas *eb)
1391 {
1392 	struct i915_vma *vma = list_entry(eb->vmas.prev, typeof(*vma), exec_list);
1393 
1394 	/*
1395 	 * SNA is doing fancy tricks with compressing batch buffers, which leads
1396 	 * to negative relocation deltas. Usually that works out ok since the
1397 	 * relocate address is still positive, except when the batch is placed
1398 	 * very low in the GTT. Ensure this doesn't happen.
1399 	 *
1400 	 * Note that actual hangs have only been observed on gen7, but for
1401 	 * paranoia do it everywhere.
1402 	 */
1403 	vma->exec_entry->flags |= __EXEC_OBJECT_NEEDS_BIAS;
1404 
1405 	return vma->obj;
1406 }
1407 
1408 static int
1409 i915_gem_do_execbuffer(struct drm_device *dev, void *data,
1410 		       struct drm_file *file,
1411 		       struct drm_i915_gem_execbuffer2 *args,
1412 		       struct drm_i915_gem_exec_object2 *exec)
1413 {
1414 	struct drm_i915_private *dev_priv = dev->dev_private;
1415 	struct eb_vmas *eb;
1416 	struct drm_i915_gem_object *batch_obj;
1417 	struct drm_i915_gem_exec_object2 shadow_exec_entry;
1418 	struct intel_engine_cs *ring;
1419 	struct intel_context *ctx;
1420 	struct i915_address_space *vm;
1421 	struct i915_execbuffer_params params_master; /* XXX: will be removed later */
1422 	struct i915_execbuffer_params *params = &params_master;
1423 	const u32 ctx_id = i915_execbuffer2_get_context_id(*args);
1424 	u32 dispatch_flags;
1425 	int ret;
1426 	bool need_relocs;
1427 
1428 	if (!i915_gem_check_execbuffer(args))
1429 		return -EINVAL;
1430 
1431 	ret = validate_exec_list(dev, exec, args->buffer_count);
1432 	if (ret)
1433 		return ret;
1434 
1435 	dispatch_flags = 0;
1436 	if (args->flags & I915_EXEC_SECURE) {
1437 		dispatch_flags |= I915_DISPATCH_SECURE;
1438 	}
1439 	if (args->flags & I915_EXEC_IS_PINNED)
1440 		dispatch_flags |= I915_DISPATCH_PINNED;
1441 
1442 	if ((args->flags & I915_EXEC_RING_MASK) > LAST_USER_RING) {
1443 		DRM_DEBUG("execbuf with unknown ring: %d\n",
1444 			  (int)(args->flags & I915_EXEC_RING_MASK));
1445 		return -EINVAL;
1446 	}
1447 
1448 	if (((args->flags & I915_EXEC_RING_MASK) != I915_EXEC_BSD) &&
1449 	    ((args->flags & I915_EXEC_BSD_MASK) != 0)) {
1450 		DRM_DEBUG("execbuf with non bsd ring but with invalid "
1451 			"bsd dispatch flags: %d\n", (int)(args->flags));
1452 		return -EINVAL;
1453 	}
1454 
1455 	if ((args->flags & I915_EXEC_RING_MASK) == I915_EXEC_DEFAULT)
1456 		ring = &dev_priv->ring[RCS];
1457 	else if ((args->flags & I915_EXEC_RING_MASK) == I915_EXEC_BSD) {
1458 		if (HAS_BSD2(dev)) {
1459 			int ring_id;
1460 
1461 			switch (args->flags & I915_EXEC_BSD_MASK) {
1462 			case I915_EXEC_BSD_DEFAULT:
1463 				ring_id = gen8_dispatch_bsd_ring(dev, file);
1464 				ring = &dev_priv->ring[ring_id];
1465 				break;
1466 			case I915_EXEC_BSD_RING1:
1467 				ring = &dev_priv->ring[VCS];
1468 				break;
1469 			case I915_EXEC_BSD_RING2:
1470 				ring = &dev_priv->ring[VCS2];
1471 				break;
1472 			default:
1473 				DRM_DEBUG("execbuf with unknown bsd ring: %d\n",
1474 					  (int)(args->flags & I915_EXEC_BSD_MASK));
1475 				return -EINVAL;
1476 			}
1477 		} else
1478 			ring = &dev_priv->ring[VCS];
1479 	} else
1480 		ring = &dev_priv->ring[(args->flags & I915_EXEC_RING_MASK) - 1];
1481 
1482 	if (!intel_ring_initialized(ring)) {
1483 		DRM_DEBUG("execbuf with invalid ring: %d\n",
1484 			  (int)(args->flags & I915_EXEC_RING_MASK));
1485 		return -EINVAL;
1486 	}
1487 
1488 	if (args->buffer_count < 1) {
1489 		DRM_DEBUG("execbuf with %d buffers\n", args->buffer_count);
1490 		return -EINVAL;
1491 	}
1492 
1493 	if (args->flags & I915_EXEC_RESOURCE_STREAMER) {
1494 		if (!HAS_RESOURCE_STREAMER(dev)) {
1495 			DRM_DEBUG("RS is only allowed for Haswell, Gen8 and above\n");
1496 			return -EINVAL;
1497 		}
1498 		if (ring->id != RCS) {
1499 			DRM_DEBUG("RS is not available on %s\n",
1500 				 ring->name);
1501 			return -EINVAL;
1502 		}
1503 
1504 		dispatch_flags |= I915_DISPATCH_RS;
1505 	}
1506 
1507 	intel_runtime_pm_get(dev_priv);
1508 
1509 	ret = i915_mutex_lock_interruptible(dev);
1510 	if (ret)
1511 		goto pre_mutex_err;
1512 
1513 	ctx = i915_gem_validate_context(dev, file, ring, ctx_id);
1514 	if (IS_ERR(ctx)) {
1515 		mutex_unlock(&dev->struct_mutex);
1516 		ret = PTR_ERR(ctx);
1517 		goto pre_mutex_err;
1518 	}
1519 
1520 	i915_gem_context_reference(ctx);
1521 
1522 	if (ctx->ppgtt)
1523 		vm = &ctx->ppgtt->base;
1524 	else
1525 		vm = &dev_priv->gtt.base;
1526 
1527 	memset(&params_master, 0x00, sizeof(params_master));
1528 
1529 	eb = eb_create(args);
1530 	if (eb == NULL) {
1531 		i915_gem_context_unreference(ctx);
1532 		mutex_unlock(&dev->struct_mutex);
1533 		ret = -ENOMEM;
1534 		goto pre_mutex_err;
1535 	}
1536 
1537 	/* Look up object handles */
1538 	ret = eb_lookup_vmas(eb, exec, args, vm, file);
1539 	if (ret)
1540 		goto err;
1541 
1542 	/* take note of the batch buffer before we might reorder the lists */
1543 	batch_obj = eb_get_batch(eb);
1544 
1545 	/* Move the objects en-masse into the GTT, evicting if necessary. */
1546 	need_relocs = (args->flags & I915_EXEC_NO_RELOC) == 0;
1547 	ret = i915_gem_execbuffer_reserve(ring, &eb->vmas, ctx, &need_relocs);
1548 	if (ret)
1549 		goto err;
1550 
1551 	/* The objects are in their final locations, apply the relocations. */
1552 	if (need_relocs)
1553 		ret = i915_gem_execbuffer_relocate(eb);
1554 	if (ret) {
1555 		if (ret == -EFAULT) {
1556 			ret = i915_gem_execbuffer_relocate_slow(dev, args, file, ring,
1557 								eb, exec, ctx);
1558 			BUG_ON(!mutex_is_locked(&dev->struct_mutex));
1559 		}
1560 		if (ret)
1561 			goto err;
1562 	}
1563 
1564 	/* Set the pending read domains for the batch buffer to COMMAND */
1565 	if (batch_obj->base.pending_write_domain) {
1566 		DRM_DEBUG("Attempting to use self-modifying batch buffer\n");
1567 		ret = -EINVAL;
1568 		goto err;
1569 	}
1570 
1571 	params->args_batch_start_offset = args->batch_start_offset;
1572 	if (i915_needs_cmd_parser(ring) && args->batch_len) {
1573 		struct drm_i915_gem_object *parsed_batch_obj;
1574 
1575 		parsed_batch_obj = i915_gem_execbuffer_parse(ring,
1576 						      &shadow_exec_entry,
1577 						      eb,
1578 						      batch_obj,
1579 						      args->batch_start_offset,
1580 						      args->batch_len,
1581 						      file->is_master);
1582 		if (IS_ERR(parsed_batch_obj)) {
1583 			ret = PTR_ERR(parsed_batch_obj);
1584 			goto err;
1585 		}
1586 
1587 		/*
1588 		 * parsed_batch_obj == batch_obj means batch not fully parsed:
1589 		 * Accept, but don't promote to secure.
1590 		 */
1591 
1592 		if (parsed_batch_obj != batch_obj) {
1593 			/*
1594 			 * Batch parsed and accepted:
1595 			 *
1596 			 * Set the DISPATCH_SECURE bit to remove the NON_SECURE
1597 			 * bit from MI_BATCH_BUFFER_START commands issued in
1598 			 * the dispatch_execbuffer implementations. We
1599 			 * specifically don't want that set on batches the
1600 			 * command parser has accepted.
1601 			 */
1602 			dispatch_flags |= I915_DISPATCH_SECURE;
1603 			params->args_batch_start_offset = 0;
1604 			batch_obj = parsed_batch_obj;
1605 		}
1606 	}
1607 
1608 	batch_obj->base.pending_read_domains |= I915_GEM_DOMAIN_COMMAND;
1609 
1610 	/* snb/ivb/vlv conflate the "batch in ppgtt" bit with the "non-secure
1611 	 * batch" bit. Hence we need to pin secure batches into the global gtt.
1612 	 * hsw should have this fixed, but bdw mucks it up again. */
1613 	if (dispatch_flags & I915_DISPATCH_SECURE) {
1614 		/*
1615 		 * So on first glance it looks freaky that we pin the batch here
1616 		 * outside of the reservation loop. But:
1617 		 * - The batch is already pinned into the relevant ppgtt, so we
1618 		 *   already have the backing storage fully allocated.
1619 		 * - No other BO uses the global gtt (well contexts, but meh),
1620 		 *   so we don't really have issues with multiple objects not
1621 		 *   fitting due to fragmentation.
1622 		 * So this is actually safe.
1623 		 */
1624 		ret = i915_gem_obj_ggtt_pin(batch_obj, 0, 0);
1625 		if (ret)
1626 			goto err;
1627 
1628 		params->batch_obj_vm_offset = i915_gem_obj_ggtt_offset(batch_obj);
1629 	} else
1630 		params->batch_obj_vm_offset = i915_gem_obj_offset(batch_obj, vm);
1631 
1632 	/* Allocate a request for this batch buffer nice and early. */
1633 	ret = i915_gem_request_alloc(ring, ctx, &params->request);
1634 	if (ret)
1635 		goto err_batch_unpin;
1636 
1637 	ret = i915_gem_request_add_to_client(params->request, file);
1638 	if (ret)
1639 		goto err_batch_unpin;
1640 
1641 	/*
1642 	 * Save assorted stuff away to pass through to *_submission().
1643 	 * NB: This data should be 'persistent' and not local as it will
1644 	 * kept around beyond the duration of the IOCTL once the GPU
1645 	 * scheduler arrives.
1646 	 */
1647 	params->dev                     = dev;
1648 	params->file                    = file;
1649 	params->ring                    = ring;
1650 	params->dispatch_flags          = dispatch_flags;
1651 	params->batch_obj               = batch_obj;
1652 	params->ctx                     = ctx;
1653 
1654 	ret = dev_priv->gt.execbuf_submit(params, args, &eb->vmas);
1655 
1656 err_batch_unpin:
1657 	/*
1658 	 * FIXME: We crucially rely upon the active tracking for the (ppgtt)
1659 	 * batch vma for correctness. For less ugly and less fragility this
1660 	 * needs to be adjusted to also track the ggtt batch vma properly as
1661 	 * active.
1662 	 */
1663 	if (dispatch_flags & I915_DISPATCH_SECURE)
1664 		i915_gem_object_ggtt_unpin(batch_obj);
1665 
1666 err:
1667 	/* the request owns the ref now */
1668 	i915_gem_context_unreference(ctx);
1669 	eb_destroy(eb);
1670 
1671 	/*
1672 	 * If the request was created but not successfully submitted then it
1673 	 * must be freed again. If it was submitted then it is being tracked
1674 	 * on the active request list and no clean up is required here.
1675 	 */
1676 	if (ret && params->request)
1677 		i915_gem_request_cancel(params->request);
1678 
1679 	mutex_unlock(&dev->struct_mutex);
1680 
1681 pre_mutex_err:
1682 	/* intel_gpu_busy should also get a ref, so it will free when the device
1683 	 * is really idle. */
1684 	intel_runtime_pm_put(dev_priv);
1685 	return ret;
1686 }
1687 
1688 /*
1689  * Legacy execbuffer just creates an exec2 list from the original exec object
1690  * list array and passes it to the real function.
1691  */
1692 int
1693 i915_gem_execbuffer(struct drm_device *dev, void *data,
1694 		    struct drm_file *file)
1695 {
1696 	struct drm_i915_gem_execbuffer *args = data;
1697 	struct drm_i915_gem_execbuffer2 exec2;
1698 	struct drm_i915_gem_exec_object *exec_list = NULL;
1699 	struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1700 	int ret, i;
1701 
1702 	if (args->buffer_count < 1) {
1703 		DRM_DEBUG("execbuf with %d buffers\n", args->buffer_count);
1704 		return -EINVAL;
1705 	}
1706 
1707 	/* Copy in the exec list from userland */
1708 	exec_list = drm_malloc_ab(sizeof(*exec_list), args->buffer_count);
1709 	exec2_list = drm_malloc_ab(sizeof(*exec2_list), args->buffer_count);
1710 	if (exec_list == NULL || exec2_list == NULL) {
1711 		DRM_DEBUG("Failed to allocate exec list for %d buffers\n",
1712 			  args->buffer_count);
1713 		drm_free_large(exec_list);
1714 		drm_free_large(exec2_list);
1715 		return -ENOMEM;
1716 	}
1717 	ret = copy_from_user(exec_list,
1718 			     to_user_ptr(args->buffers_ptr),
1719 			     sizeof(*exec_list) * args->buffer_count);
1720 	if (ret != 0) {
1721 		DRM_DEBUG("copy %d exec entries failed %d\n",
1722 			  args->buffer_count, ret);
1723 		drm_free_large(exec_list);
1724 		drm_free_large(exec2_list);
1725 		return -EFAULT;
1726 	}
1727 
1728 	for (i = 0; i < args->buffer_count; i++) {
1729 		exec2_list[i].handle = exec_list[i].handle;
1730 		exec2_list[i].relocation_count = exec_list[i].relocation_count;
1731 		exec2_list[i].relocs_ptr = exec_list[i].relocs_ptr;
1732 		exec2_list[i].alignment = exec_list[i].alignment;
1733 		exec2_list[i].offset = exec_list[i].offset;
1734 		if (INTEL_INFO(dev)->gen < 4)
1735 			exec2_list[i].flags = EXEC_OBJECT_NEEDS_FENCE;
1736 		else
1737 			exec2_list[i].flags = 0;
1738 	}
1739 
1740 	exec2.buffers_ptr = args->buffers_ptr;
1741 	exec2.buffer_count = args->buffer_count;
1742 	exec2.batch_start_offset = args->batch_start_offset;
1743 	exec2.batch_len = args->batch_len;
1744 	exec2.DR1 = args->DR1;
1745 	exec2.DR4 = args->DR4;
1746 	exec2.num_cliprects = args->num_cliprects;
1747 	exec2.cliprects_ptr = args->cliprects_ptr;
1748 	exec2.flags = I915_EXEC_RENDER;
1749 	i915_execbuffer2_set_context_id(exec2, 0);
1750 
1751 	ret = i915_gem_do_execbuffer(dev, data, file, &exec2, exec2_list);
1752 	if (!ret) {
1753 		struct drm_i915_gem_exec_object __user *user_exec_list =
1754 			to_user_ptr(args->buffers_ptr);
1755 
1756 		/* Copy the new buffer offsets back to the user's exec list. */
1757 		for (i = 0; i < args->buffer_count; i++) {
1758 			ret = __copy_to_user(&user_exec_list[i].offset,
1759 					     &exec2_list[i].offset,
1760 					     sizeof(user_exec_list[i].offset));
1761 			if (ret) {
1762 				ret = -EFAULT;
1763 				DRM_DEBUG("failed to copy %d exec entries "
1764 					  "back to user (%d)\n",
1765 					  args->buffer_count, ret);
1766 				break;
1767 			}
1768 		}
1769 	}
1770 
1771 	drm_free_large(exec_list);
1772 	drm_free_large(exec2_list);
1773 	return ret;
1774 }
1775 
1776 int
1777 i915_gem_execbuffer2(struct drm_device *dev, void *data,
1778 		     struct drm_file *file)
1779 {
1780 	struct drm_i915_gem_execbuffer2 *args = data;
1781 	struct drm_i915_gem_exec_object2 *exec2_list = NULL;
1782 	int ret;
1783 
1784 	if (args->buffer_count < 1 ||
1785 	    args->buffer_count > UINT_MAX / sizeof(*exec2_list)) {
1786 		DRM_DEBUG("execbuf2 with %d buffers\n", args->buffer_count);
1787 		return -EINVAL;
1788 	}
1789 
1790 	if (args->rsvd2 != 0) {
1791 		DRM_DEBUG("dirty rvsd2 field\n");
1792 		return -EINVAL;
1793 	}
1794 
1795 	exec2_list = kmalloc(sizeof(*exec2_list)*args->buffer_count,
1796 			     M_DRM, M_NOWAIT);
1797 	if (exec2_list == NULL)
1798 		exec2_list = drm_malloc_ab(sizeof(*exec2_list),
1799 					   args->buffer_count);
1800 	if (exec2_list == NULL) {
1801 		DRM_DEBUG("Failed to allocate exec list for %d buffers\n",
1802 			  args->buffer_count);
1803 		return -ENOMEM;
1804 	}
1805 	ret = copy_from_user(exec2_list,
1806 			     to_user_ptr(args->buffers_ptr),
1807 			     sizeof(*exec2_list) * args->buffer_count);
1808 	if (ret != 0) {
1809 		DRM_DEBUG("copy %d exec entries failed %d\n",
1810 			  args->buffer_count, ret);
1811 		drm_free_large(exec2_list);
1812 		return -EFAULT;
1813 	}
1814 
1815 	ret = i915_gem_do_execbuffer(dev, data, file, args, exec2_list);
1816 	if (!ret) {
1817 		/* Copy the new buffer offsets back to the user's exec list. */
1818 		struct drm_i915_gem_exec_object2 __user *user_exec_list =
1819 				   to_user_ptr(args->buffers_ptr);
1820 		int i;
1821 
1822 		for (i = 0; i < args->buffer_count; i++) {
1823 			ret = __copy_to_user(&user_exec_list[i].offset,
1824 					     &exec2_list[i].offset,
1825 					     sizeof(user_exec_list[i].offset));
1826 			if (ret) {
1827 				ret = -EFAULT;
1828 				DRM_DEBUG("failed to copy %d exec entries "
1829 					  "back to user\n",
1830 					  args->buffer_count);
1831 				break;
1832 			}
1833 		}
1834 	}
1835 
1836 	drm_free_large(exec2_list);
1837 	return ret;
1838 }
1839