xref: /linux/drivers/gpu/drm/i915/i915_gem.c (revision 5d4a2e29fba5b2bef95b96a46b338ec4d76fa4fd)
1 /*
2  * Copyright © 2008 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  *
26  */
27 
28 #include "drmP.h"
29 #include "drm.h"
30 #include "i915_drm.h"
31 #include "i915_drv.h"
32 #include "i915_trace.h"
33 #include "intel_drv.h"
34 #include <linux/slab.h>
35 #include <linux/swap.h>
36 #include <linux/pci.h>
37 
38 static void i915_gem_object_flush_gpu_write_domain(struct drm_gem_object *obj);
39 static void i915_gem_object_flush_gtt_write_domain(struct drm_gem_object *obj);
40 static void i915_gem_object_flush_cpu_write_domain(struct drm_gem_object *obj);
41 static int i915_gem_object_set_to_cpu_domain(struct drm_gem_object *obj,
42 					     int write);
43 static int i915_gem_object_set_cpu_read_domain_range(struct drm_gem_object *obj,
44 						     uint64_t offset,
45 						     uint64_t size);
46 static void i915_gem_object_set_to_full_cpu_read_domain(struct drm_gem_object *obj);
47 static int i915_gem_object_wait_rendering(struct drm_gem_object *obj);
48 static int i915_gem_object_bind_to_gtt(struct drm_gem_object *obj,
49 					   unsigned alignment);
50 static void i915_gem_clear_fence_reg(struct drm_gem_object *obj);
51 static int i915_gem_evict_something(struct drm_device *dev, int min_size);
52 static int i915_gem_evict_from_inactive_list(struct drm_device *dev);
53 static int i915_gem_phys_pwrite(struct drm_device *dev, struct drm_gem_object *obj,
54 				struct drm_i915_gem_pwrite *args,
55 				struct drm_file *file_priv);
56 
57 static LIST_HEAD(shrink_list);
58 static DEFINE_SPINLOCK(shrink_list_lock);
59 
60 int i915_gem_do_init(struct drm_device *dev, unsigned long start,
61 		     unsigned long end)
62 {
63 	drm_i915_private_t *dev_priv = dev->dev_private;
64 
65 	if (start >= end ||
66 	    (start & (PAGE_SIZE - 1)) != 0 ||
67 	    (end & (PAGE_SIZE - 1)) != 0) {
68 		return -EINVAL;
69 	}
70 
71 	drm_mm_init(&dev_priv->mm.gtt_space, start,
72 		    end - start);
73 
74 	dev->gtt_total = (uint32_t) (end - start);
75 
76 	return 0;
77 }
78 
79 int
80 i915_gem_init_ioctl(struct drm_device *dev, void *data,
81 		    struct drm_file *file_priv)
82 {
83 	struct drm_i915_gem_init *args = data;
84 	int ret;
85 
86 	mutex_lock(&dev->struct_mutex);
87 	ret = i915_gem_do_init(dev, args->gtt_start, args->gtt_end);
88 	mutex_unlock(&dev->struct_mutex);
89 
90 	return ret;
91 }
92 
93 int
94 i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data,
95 			    struct drm_file *file_priv)
96 {
97 	struct drm_i915_gem_get_aperture *args = data;
98 
99 	if (!(dev->driver->driver_features & DRIVER_GEM))
100 		return -ENODEV;
101 
102 	args->aper_size = dev->gtt_total;
103 	args->aper_available_size = (args->aper_size -
104 				     atomic_read(&dev->pin_memory));
105 
106 	return 0;
107 }
108 
109 
110 /**
111  * Creates a new mm object and returns a handle to it.
112  */
113 int
114 i915_gem_create_ioctl(struct drm_device *dev, void *data,
115 		      struct drm_file *file_priv)
116 {
117 	struct drm_i915_gem_create *args = data;
118 	struct drm_gem_object *obj;
119 	int ret;
120 	u32 handle;
121 
122 	args->size = roundup(args->size, PAGE_SIZE);
123 
124 	/* Allocate the new object */
125 	obj = i915_gem_alloc_object(dev, args->size);
126 	if (obj == NULL)
127 		return -ENOMEM;
128 
129 	ret = drm_gem_handle_create(file_priv, obj, &handle);
130 	drm_gem_object_handle_unreference_unlocked(obj);
131 
132 	if (ret)
133 		return ret;
134 
135 	args->handle = handle;
136 
137 	return 0;
138 }
139 
140 static inline int
141 fast_shmem_read(struct page **pages,
142 		loff_t page_base, int page_offset,
143 		char __user *data,
144 		int length)
145 {
146 	char __iomem *vaddr;
147 	int unwritten;
148 
149 	vaddr = kmap_atomic(pages[page_base >> PAGE_SHIFT], KM_USER0);
150 	if (vaddr == NULL)
151 		return -ENOMEM;
152 	unwritten = __copy_to_user_inatomic(data, vaddr + page_offset, length);
153 	kunmap_atomic(vaddr, KM_USER0);
154 
155 	if (unwritten)
156 		return -EFAULT;
157 
158 	return 0;
159 }
160 
161 static int i915_gem_object_needs_bit17_swizzle(struct drm_gem_object *obj)
162 {
163 	drm_i915_private_t *dev_priv = obj->dev->dev_private;
164 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
165 
166 	return dev_priv->mm.bit_6_swizzle_x == I915_BIT_6_SWIZZLE_9_10_17 &&
167 		obj_priv->tiling_mode != I915_TILING_NONE;
168 }
169 
170 static inline void
171 slow_shmem_copy(struct page *dst_page,
172 		int dst_offset,
173 		struct page *src_page,
174 		int src_offset,
175 		int length)
176 {
177 	char *dst_vaddr, *src_vaddr;
178 
179 	dst_vaddr = kmap(dst_page);
180 	src_vaddr = kmap(src_page);
181 
182 	memcpy(dst_vaddr + dst_offset, src_vaddr + src_offset, length);
183 
184 	kunmap(src_page);
185 	kunmap(dst_page);
186 }
187 
188 static inline void
189 slow_shmem_bit17_copy(struct page *gpu_page,
190 		      int gpu_offset,
191 		      struct page *cpu_page,
192 		      int cpu_offset,
193 		      int length,
194 		      int is_read)
195 {
196 	char *gpu_vaddr, *cpu_vaddr;
197 
198 	/* Use the unswizzled path if this page isn't affected. */
199 	if ((page_to_phys(gpu_page) & (1 << 17)) == 0) {
200 		if (is_read)
201 			return slow_shmem_copy(cpu_page, cpu_offset,
202 					       gpu_page, gpu_offset, length);
203 		else
204 			return slow_shmem_copy(gpu_page, gpu_offset,
205 					       cpu_page, cpu_offset, length);
206 	}
207 
208 	gpu_vaddr = kmap(gpu_page);
209 	cpu_vaddr = kmap(cpu_page);
210 
211 	/* Copy the data, XORing A6 with A17 (1). The user already knows he's
212 	 * XORing with the other bits (A9 for Y, A9 and A10 for X)
213 	 */
214 	while (length > 0) {
215 		int cacheline_end = ALIGN(gpu_offset + 1, 64);
216 		int this_length = min(cacheline_end - gpu_offset, length);
217 		int swizzled_gpu_offset = gpu_offset ^ 64;
218 
219 		if (is_read) {
220 			memcpy(cpu_vaddr + cpu_offset,
221 			       gpu_vaddr + swizzled_gpu_offset,
222 			       this_length);
223 		} else {
224 			memcpy(gpu_vaddr + swizzled_gpu_offset,
225 			       cpu_vaddr + cpu_offset,
226 			       this_length);
227 		}
228 		cpu_offset += this_length;
229 		gpu_offset += this_length;
230 		length -= this_length;
231 	}
232 
233 	kunmap(cpu_page);
234 	kunmap(gpu_page);
235 }
236 
237 /**
238  * This is the fast shmem pread path, which attempts to copy_from_user directly
239  * from the backing pages of the object to the user's address space.  On a
240  * fault, it fails so we can fall back to i915_gem_shmem_pwrite_slow().
241  */
242 static int
243 i915_gem_shmem_pread_fast(struct drm_device *dev, struct drm_gem_object *obj,
244 			  struct drm_i915_gem_pread *args,
245 			  struct drm_file *file_priv)
246 {
247 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
248 	ssize_t remain;
249 	loff_t offset, page_base;
250 	char __user *user_data;
251 	int page_offset, page_length;
252 	int ret;
253 
254 	user_data = (char __user *) (uintptr_t) args->data_ptr;
255 	remain = args->size;
256 
257 	mutex_lock(&dev->struct_mutex);
258 
259 	ret = i915_gem_object_get_pages(obj, 0);
260 	if (ret != 0)
261 		goto fail_unlock;
262 
263 	ret = i915_gem_object_set_cpu_read_domain_range(obj, args->offset,
264 							args->size);
265 	if (ret != 0)
266 		goto fail_put_pages;
267 
268 	obj_priv = to_intel_bo(obj);
269 	offset = args->offset;
270 
271 	while (remain > 0) {
272 		/* Operation in this page
273 		 *
274 		 * page_base = page offset within aperture
275 		 * page_offset = offset within page
276 		 * page_length = bytes to copy for this page
277 		 */
278 		page_base = (offset & ~(PAGE_SIZE-1));
279 		page_offset = offset & (PAGE_SIZE-1);
280 		page_length = remain;
281 		if ((page_offset + remain) > PAGE_SIZE)
282 			page_length = PAGE_SIZE - page_offset;
283 
284 		ret = fast_shmem_read(obj_priv->pages,
285 				      page_base, page_offset,
286 				      user_data, page_length);
287 		if (ret)
288 			goto fail_put_pages;
289 
290 		remain -= page_length;
291 		user_data += page_length;
292 		offset += page_length;
293 	}
294 
295 fail_put_pages:
296 	i915_gem_object_put_pages(obj);
297 fail_unlock:
298 	mutex_unlock(&dev->struct_mutex);
299 
300 	return ret;
301 }
302 
303 static int
304 i915_gem_object_get_pages_or_evict(struct drm_gem_object *obj)
305 {
306 	int ret;
307 
308 	ret = i915_gem_object_get_pages(obj, __GFP_NORETRY | __GFP_NOWARN);
309 
310 	/* If we've insufficient memory to map in the pages, attempt
311 	 * to make some space by throwing out some old buffers.
312 	 */
313 	if (ret == -ENOMEM) {
314 		struct drm_device *dev = obj->dev;
315 
316 		ret = i915_gem_evict_something(dev, obj->size);
317 		if (ret)
318 			return ret;
319 
320 		ret = i915_gem_object_get_pages(obj, 0);
321 	}
322 
323 	return ret;
324 }
325 
326 /**
327  * This is the fallback shmem pread path, which allocates temporary storage
328  * in kernel space to copy_to_user into outside of the struct_mutex, so we
329  * can copy out of the object's backing pages while holding the struct mutex
330  * and not take page faults.
331  */
332 static int
333 i915_gem_shmem_pread_slow(struct drm_device *dev, struct drm_gem_object *obj,
334 			  struct drm_i915_gem_pread *args,
335 			  struct drm_file *file_priv)
336 {
337 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
338 	struct mm_struct *mm = current->mm;
339 	struct page **user_pages;
340 	ssize_t remain;
341 	loff_t offset, pinned_pages, i;
342 	loff_t first_data_page, last_data_page, num_pages;
343 	int shmem_page_index, shmem_page_offset;
344 	int data_page_index,  data_page_offset;
345 	int page_length;
346 	int ret;
347 	uint64_t data_ptr = args->data_ptr;
348 	int do_bit17_swizzling;
349 
350 	remain = args->size;
351 
352 	/* Pin the user pages containing the data.  We can't fault while
353 	 * holding the struct mutex, yet we want to hold it while
354 	 * dereferencing the user data.
355 	 */
356 	first_data_page = data_ptr / PAGE_SIZE;
357 	last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE;
358 	num_pages = last_data_page - first_data_page + 1;
359 
360 	user_pages = drm_calloc_large(num_pages, sizeof(struct page *));
361 	if (user_pages == NULL)
362 		return -ENOMEM;
363 
364 	down_read(&mm->mmap_sem);
365 	pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr,
366 				      num_pages, 1, 0, user_pages, NULL);
367 	up_read(&mm->mmap_sem);
368 	if (pinned_pages < num_pages) {
369 		ret = -EFAULT;
370 		goto fail_put_user_pages;
371 	}
372 
373 	do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj);
374 
375 	mutex_lock(&dev->struct_mutex);
376 
377 	ret = i915_gem_object_get_pages_or_evict(obj);
378 	if (ret)
379 		goto fail_unlock;
380 
381 	ret = i915_gem_object_set_cpu_read_domain_range(obj, args->offset,
382 							args->size);
383 	if (ret != 0)
384 		goto fail_put_pages;
385 
386 	obj_priv = to_intel_bo(obj);
387 	offset = args->offset;
388 
389 	while (remain > 0) {
390 		/* Operation in this page
391 		 *
392 		 * shmem_page_index = page number within shmem file
393 		 * shmem_page_offset = offset within page in shmem file
394 		 * data_page_index = page number in get_user_pages return
395 		 * data_page_offset = offset with data_page_index page.
396 		 * page_length = bytes to copy for this page
397 		 */
398 		shmem_page_index = offset / PAGE_SIZE;
399 		shmem_page_offset = offset & ~PAGE_MASK;
400 		data_page_index = data_ptr / PAGE_SIZE - first_data_page;
401 		data_page_offset = data_ptr & ~PAGE_MASK;
402 
403 		page_length = remain;
404 		if ((shmem_page_offset + page_length) > PAGE_SIZE)
405 			page_length = PAGE_SIZE - shmem_page_offset;
406 		if ((data_page_offset + page_length) > PAGE_SIZE)
407 			page_length = PAGE_SIZE - data_page_offset;
408 
409 		if (do_bit17_swizzling) {
410 			slow_shmem_bit17_copy(obj_priv->pages[shmem_page_index],
411 					      shmem_page_offset,
412 					      user_pages[data_page_index],
413 					      data_page_offset,
414 					      page_length,
415 					      1);
416 		} else {
417 			slow_shmem_copy(user_pages[data_page_index],
418 					data_page_offset,
419 					obj_priv->pages[shmem_page_index],
420 					shmem_page_offset,
421 					page_length);
422 		}
423 
424 		remain -= page_length;
425 		data_ptr += page_length;
426 		offset += page_length;
427 	}
428 
429 fail_put_pages:
430 	i915_gem_object_put_pages(obj);
431 fail_unlock:
432 	mutex_unlock(&dev->struct_mutex);
433 fail_put_user_pages:
434 	for (i = 0; i < pinned_pages; i++) {
435 		SetPageDirty(user_pages[i]);
436 		page_cache_release(user_pages[i]);
437 	}
438 	drm_free_large(user_pages);
439 
440 	return ret;
441 }
442 
443 /**
444  * Reads data from the object referenced by handle.
445  *
446  * On error, the contents of *data are undefined.
447  */
448 int
449 i915_gem_pread_ioctl(struct drm_device *dev, void *data,
450 		     struct drm_file *file_priv)
451 {
452 	struct drm_i915_gem_pread *args = data;
453 	struct drm_gem_object *obj;
454 	struct drm_i915_gem_object *obj_priv;
455 	int ret;
456 
457 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
458 	if (obj == NULL)
459 		return -EBADF;
460 	obj_priv = to_intel_bo(obj);
461 
462 	/* Bounds check source.
463 	 *
464 	 * XXX: This could use review for overflow issues...
465 	 */
466 	if (args->offset > obj->size || args->size > obj->size ||
467 	    args->offset + args->size > obj->size) {
468 		drm_gem_object_unreference_unlocked(obj);
469 		return -EINVAL;
470 	}
471 
472 	if (i915_gem_object_needs_bit17_swizzle(obj)) {
473 		ret = i915_gem_shmem_pread_slow(dev, obj, args, file_priv);
474 	} else {
475 		ret = i915_gem_shmem_pread_fast(dev, obj, args, file_priv);
476 		if (ret != 0)
477 			ret = i915_gem_shmem_pread_slow(dev, obj, args,
478 							file_priv);
479 	}
480 
481 	drm_gem_object_unreference_unlocked(obj);
482 
483 	return ret;
484 }
485 
486 /* This is the fast write path which cannot handle
487  * page faults in the source data
488  */
489 
490 static inline int
491 fast_user_write(struct io_mapping *mapping,
492 		loff_t page_base, int page_offset,
493 		char __user *user_data,
494 		int length)
495 {
496 	char *vaddr_atomic;
497 	unsigned long unwritten;
498 
499 	vaddr_atomic = io_mapping_map_atomic_wc(mapping, page_base);
500 	unwritten = __copy_from_user_inatomic_nocache(vaddr_atomic + page_offset,
501 						      user_data, length);
502 	io_mapping_unmap_atomic(vaddr_atomic);
503 	if (unwritten)
504 		return -EFAULT;
505 	return 0;
506 }
507 
508 /* Here's the write path which can sleep for
509  * page faults
510  */
511 
512 static inline void
513 slow_kernel_write(struct io_mapping *mapping,
514 		  loff_t gtt_base, int gtt_offset,
515 		  struct page *user_page, int user_offset,
516 		  int length)
517 {
518 	char __iomem *dst_vaddr;
519 	char *src_vaddr;
520 
521 	dst_vaddr = io_mapping_map_wc(mapping, gtt_base);
522 	src_vaddr = kmap(user_page);
523 
524 	memcpy_toio(dst_vaddr + gtt_offset,
525 		    src_vaddr + user_offset,
526 		    length);
527 
528 	kunmap(user_page);
529 	io_mapping_unmap(dst_vaddr);
530 }
531 
532 static inline int
533 fast_shmem_write(struct page **pages,
534 		 loff_t page_base, int page_offset,
535 		 char __user *data,
536 		 int length)
537 {
538 	char __iomem *vaddr;
539 	unsigned long unwritten;
540 
541 	vaddr = kmap_atomic(pages[page_base >> PAGE_SHIFT], KM_USER0);
542 	if (vaddr == NULL)
543 		return -ENOMEM;
544 	unwritten = __copy_from_user_inatomic(vaddr + page_offset, data, length);
545 	kunmap_atomic(vaddr, KM_USER0);
546 
547 	if (unwritten)
548 		return -EFAULT;
549 	return 0;
550 }
551 
552 /**
553  * This is the fast pwrite path, where we copy the data directly from the
554  * user into the GTT, uncached.
555  */
556 static int
557 i915_gem_gtt_pwrite_fast(struct drm_device *dev, struct drm_gem_object *obj,
558 			 struct drm_i915_gem_pwrite *args,
559 			 struct drm_file *file_priv)
560 {
561 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
562 	drm_i915_private_t *dev_priv = dev->dev_private;
563 	ssize_t remain;
564 	loff_t offset, page_base;
565 	char __user *user_data;
566 	int page_offset, page_length;
567 	int ret;
568 
569 	user_data = (char __user *) (uintptr_t) args->data_ptr;
570 	remain = args->size;
571 	if (!access_ok(VERIFY_READ, user_data, remain))
572 		return -EFAULT;
573 
574 
575 	mutex_lock(&dev->struct_mutex);
576 	ret = i915_gem_object_pin(obj, 0);
577 	if (ret) {
578 		mutex_unlock(&dev->struct_mutex);
579 		return ret;
580 	}
581 	ret = i915_gem_object_set_to_gtt_domain(obj, 1);
582 	if (ret)
583 		goto fail;
584 
585 	obj_priv = to_intel_bo(obj);
586 	offset = obj_priv->gtt_offset + args->offset;
587 
588 	while (remain > 0) {
589 		/* Operation in this page
590 		 *
591 		 * page_base = page offset within aperture
592 		 * page_offset = offset within page
593 		 * page_length = bytes to copy for this page
594 		 */
595 		page_base = (offset & ~(PAGE_SIZE-1));
596 		page_offset = offset & (PAGE_SIZE-1);
597 		page_length = remain;
598 		if ((page_offset + remain) > PAGE_SIZE)
599 			page_length = PAGE_SIZE - page_offset;
600 
601 		ret = fast_user_write (dev_priv->mm.gtt_mapping, page_base,
602 				       page_offset, user_data, page_length);
603 
604 		/* If we get a fault while copying data, then (presumably) our
605 		 * source page isn't available.  Return the error and we'll
606 		 * retry in the slow path.
607 		 */
608 		if (ret)
609 			goto fail;
610 
611 		remain -= page_length;
612 		user_data += page_length;
613 		offset += page_length;
614 	}
615 
616 fail:
617 	i915_gem_object_unpin(obj);
618 	mutex_unlock(&dev->struct_mutex);
619 
620 	return ret;
621 }
622 
623 /**
624  * This is the fallback GTT pwrite path, which uses get_user_pages to pin
625  * the memory and maps it using kmap_atomic for copying.
626  *
627  * This code resulted in x11perf -rgb10text consuming about 10% more CPU
628  * than using i915_gem_gtt_pwrite_fast on a G45 (32-bit).
629  */
630 static int
631 i915_gem_gtt_pwrite_slow(struct drm_device *dev, struct drm_gem_object *obj,
632 			 struct drm_i915_gem_pwrite *args,
633 			 struct drm_file *file_priv)
634 {
635 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
636 	drm_i915_private_t *dev_priv = dev->dev_private;
637 	ssize_t remain;
638 	loff_t gtt_page_base, offset;
639 	loff_t first_data_page, last_data_page, num_pages;
640 	loff_t pinned_pages, i;
641 	struct page **user_pages;
642 	struct mm_struct *mm = current->mm;
643 	int gtt_page_offset, data_page_offset, data_page_index, page_length;
644 	int ret;
645 	uint64_t data_ptr = args->data_ptr;
646 
647 	remain = args->size;
648 
649 	/* Pin the user pages containing the data.  We can't fault while
650 	 * holding the struct mutex, and all of the pwrite implementations
651 	 * want to hold it while dereferencing the user data.
652 	 */
653 	first_data_page = data_ptr / PAGE_SIZE;
654 	last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE;
655 	num_pages = last_data_page - first_data_page + 1;
656 
657 	user_pages = drm_calloc_large(num_pages, sizeof(struct page *));
658 	if (user_pages == NULL)
659 		return -ENOMEM;
660 
661 	down_read(&mm->mmap_sem);
662 	pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr,
663 				      num_pages, 0, 0, user_pages, NULL);
664 	up_read(&mm->mmap_sem);
665 	if (pinned_pages < num_pages) {
666 		ret = -EFAULT;
667 		goto out_unpin_pages;
668 	}
669 
670 	mutex_lock(&dev->struct_mutex);
671 	ret = i915_gem_object_pin(obj, 0);
672 	if (ret)
673 		goto out_unlock;
674 
675 	ret = i915_gem_object_set_to_gtt_domain(obj, 1);
676 	if (ret)
677 		goto out_unpin_object;
678 
679 	obj_priv = to_intel_bo(obj);
680 	offset = obj_priv->gtt_offset + args->offset;
681 
682 	while (remain > 0) {
683 		/* Operation in this page
684 		 *
685 		 * gtt_page_base = page offset within aperture
686 		 * gtt_page_offset = offset within page in aperture
687 		 * data_page_index = page number in get_user_pages return
688 		 * data_page_offset = offset with data_page_index page.
689 		 * page_length = bytes to copy for this page
690 		 */
691 		gtt_page_base = offset & PAGE_MASK;
692 		gtt_page_offset = offset & ~PAGE_MASK;
693 		data_page_index = data_ptr / PAGE_SIZE - first_data_page;
694 		data_page_offset = data_ptr & ~PAGE_MASK;
695 
696 		page_length = remain;
697 		if ((gtt_page_offset + page_length) > PAGE_SIZE)
698 			page_length = PAGE_SIZE - gtt_page_offset;
699 		if ((data_page_offset + page_length) > PAGE_SIZE)
700 			page_length = PAGE_SIZE - data_page_offset;
701 
702 		slow_kernel_write(dev_priv->mm.gtt_mapping,
703 				  gtt_page_base, gtt_page_offset,
704 				  user_pages[data_page_index],
705 				  data_page_offset,
706 				  page_length);
707 
708 		remain -= page_length;
709 		offset += page_length;
710 		data_ptr += page_length;
711 	}
712 
713 out_unpin_object:
714 	i915_gem_object_unpin(obj);
715 out_unlock:
716 	mutex_unlock(&dev->struct_mutex);
717 out_unpin_pages:
718 	for (i = 0; i < pinned_pages; i++)
719 		page_cache_release(user_pages[i]);
720 	drm_free_large(user_pages);
721 
722 	return ret;
723 }
724 
725 /**
726  * This is the fast shmem pwrite path, which attempts to directly
727  * copy_from_user into the kmapped pages backing the object.
728  */
729 static int
730 i915_gem_shmem_pwrite_fast(struct drm_device *dev, struct drm_gem_object *obj,
731 			   struct drm_i915_gem_pwrite *args,
732 			   struct drm_file *file_priv)
733 {
734 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
735 	ssize_t remain;
736 	loff_t offset, page_base;
737 	char __user *user_data;
738 	int page_offset, page_length;
739 	int ret;
740 
741 	user_data = (char __user *) (uintptr_t) args->data_ptr;
742 	remain = args->size;
743 
744 	mutex_lock(&dev->struct_mutex);
745 
746 	ret = i915_gem_object_get_pages(obj, 0);
747 	if (ret != 0)
748 		goto fail_unlock;
749 
750 	ret = i915_gem_object_set_to_cpu_domain(obj, 1);
751 	if (ret != 0)
752 		goto fail_put_pages;
753 
754 	obj_priv = to_intel_bo(obj);
755 	offset = args->offset;
756 	obj_priv->dirty = 1;
757 
758 	while (remain > 0) {
759 		/* Operation in this page
760 		 *
761 		 * page_base = page offset within aperture
762 		 * page_offset = offset within page
763 		 * page_length = bytes to copy for this page
764 		 */
765 		page_base = (offset & ~(PAGE_SIZE-1));
766 		page_offset = offset & (PAGE_SIZE-1);
767 		page_length = remain;
768 		if ((page_offset + remain) > PAGE_SIZE)
769 			page_length = PAGE_SIZE - page_offset;
770 
771 		ret = fast_shmem_write(obj_priv->pages,
772 				       page_base, page_offset,
773 				       user_data, page_length);
774 		if (ret)
775 			goto fail_put_pages;
776 
777 		remain -= page_length;
778 		user_data += page_length;
779 		offset += page_length;
780 	}
781 
782 fail_put_pages:
783 	i915_gem_object_put_pages(obj);
784 fail_unlock:
785 	mutex_unlock(&dev->struct_mutex);
786 
787 	return ret;
788 }
789 
790 /**
791  * This is the fallback shmem pwrite path, which uses get_user_pages to pin
792  * the memory and maps it using kmap_atomic for copying.
793  *
794  * This avoids taking mmap_sem for faulting on the user's address while the
795  * struct_mutex is held.
796  */
797 static int
798 i915_gem_shmem_pwrite_slow(struct drm_device *dev, struct drm_gem_object *obj,
799 			   struct drm_i915_gem_pwrite *args,
800 			   struct drm_file *file_priv)
801 {
802 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
803 	struct mm_struct *mm = current->mm;
804 	struct page **user_pages;
805 	ssize_t remain;
806 	loff_t offset, pinned_pages, i;
807 	loff_t first_data_page, last_data_page, num_pages;
808 	int shmem_page_index, shmem_page_offset;
809 	int data_page_index,  data_page_offset;
810 	int page_length;
811 	int ret;
812 	uint64_t data_ptr = args->data_ptr;
813 	int do_bit17_swizzling;
814 
815 	remain = args->size;
816 
817 	/* Pin the user pages containing the data.  We can't fault while
818 	 * holding the struct mutex, and all of the pwrite implementations
819 	 * want to hold it while dereferencing the user data.
820 	 */
821 	first_data_page = data_ptr / PAGE_SIZE;
822 	last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE;
823 	num_pages = last_data_page - first_data_page + 1;
824 
825 	user_pages = drm_calloc_large(num_pages, sizeof(struct page *));
826 	if (user_pages == NULL)
827 		return -ENOMEM;
828 
829 	down_read(&mm->mmap_sem);
830 	pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr,
831 				      num_pages, 0, 0, user_pages, NULL);
832 	up_read(&mm->mmap_sem);
833 	if (pinned_pages < num_pages) {
834 		ret = -EFAULT;
835 		goto fail_put_user_pages;
836 	}
837 
838 	do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj);
839 
840 	mutex_lock(&dev->struct_mutex);
841 
842 	ret = i915_gem_object_get_pages_or_evict(obj);
843 	if (ret)
844 		goto fail_unlock;
845 
846 	ret = i915_gem_object_set_to_cpu_domain(obj, 1);
847 	if (ret != 0)
848 		goto fail_put_pages;
849 
850 	obj_priv = to_intel_bo(obj);
851 	offset = args->offset;
852 	obj_priv->dirty = 1;
853 
854 	while (remain > 0) {
855 		/* Operation in this page
856 		 *
857 		 * shmem_page_index = page number within shmem file
858 		 * shmem_page_offset = offset within page in shmem file
859 		 * data_page_index = page number in get_user_pages return
860 		 * data_page_offset = offset with data_page_index page.
861 		 * page_length = bytes to copy for this page
862 		 */
863 		shmem_page_index = offset / PAGE_SIZE;
864 		shmem_page_offset = offset & ~PAGE_MASK;
865 		data_page_index = data_ptr / PAGE_SIZE - first_data_page;
866 		data_page_offset = data_ptr & ~PAGE_MASK;
867 
868 		page_length = remain;
869 		if ((shmem_page_offset + page_length) > PAGE_SIZE)
870 			page_length = PAGE_SIZE - shmem_page_offset;
871 		if ((data_page_offset + page_length) > PAGE_SIZE)
872 			page_length = PAGE_SIZE - data_page_offset;
873 
874 		if (do_bit17_swizzling) {
875 			slow_shmem_bit17_copy(obj_priv->pages[shmem_page_index],
876 					      shmem_page_offset,
877 					      user_pages[data_page_index],
878 					      data_page_offset,
879 					      page_length,
880 					      0);
881 		} else {
882 			slow_shmem_copy(obj_priv->pages[shmem_page_index],
883 					shmem_page_offset,
884 					user_pages[data_page_index],
885 					data_page_offset,
886 					page_length);
887 		}
888 
889 		remain -= page_length;
890 		data_ptr += page_length;
891 		offset += page_length;
892 	}
893 
894 fail_put_pages:
895 	i915_gem_object_put_pages(obj);
896 fail_unlock:
897 	mutex_unlock(&dev->struct_mutex);
898 fail_put_user_pages:
899 	for (i = 0; i < pinned_pages; i++)
900 		page_cache_release(user_pages[i]);
901 	drm_free_large(user_pages);
902 
903 	return ret;
904 }
905 
906 /**
907  * Writes data to the object referenced by handle.
908  *
909  * On error, the contents of the buffer that were to be modified are undefined.
910  */
911 int
912 i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
913 		      struct drm_file *file_priv)
914 {
915 	struct drm_i915_gem_pwrite *args = data;
916 	struct drm_gem_object *obj;
917 	struct drm_i915_gem_object *obj_priv;
918 	int ret = 0;
919 
920 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
921 	if (obj == NULL)
922 		return -EBADF;
923 	obj_priv = to_intel_bo(obj);
924 
925 	/* Bounds check destination.
926 	 *
927 	 * XXX: This could use review for overflow issues...
928 	 */
929 	if (args->offset > obj->size || args->size > obj->size ||
930 	    args->offset + args->size > obj->size) {
931 		drm_gem_object_unreference_unlocked(obj);
932 		return -EINVAL;
933 	}
934 
935 	/* We can only do the GTT pwrite on untiled buffers, as otherwise
936 	 * it would end up going through the fenced access, and we'll get
937 	 * different detiling behavior between reading and writing.
938 	 * pread/pwrite currently are reading and writing from the CPU
939 	 * perspective, requiring manual detiling by the client.
940 	 */
941 	if (obj_priv->phys_obj)
942 		ret = i915_gem_phys_pwrite(dev, obj, args, file_priv);
943 	else if (obj_priv->tiling_mode == I915_TILING_NONE &&
944 		 dev->gtt_total != 0 &&
945 		 obj->write_domain != I915_GEM_DOMAIN_CPU) {
946 		ret = i915_gem_gtt_pwrite_fast(dev, obj, args, file_priv);
947 		if (ret == -EFAULT) {
948 			ret = i915_gem_gtt_pwrite_slow(dev, obj, args,
949 						       file_priv);
950 		}
951 	} else if (i915_gem_object_needs_bit17_swizzle(obj)) {
952 		ret = i915_gem_shmem_pwrite_slow(dev, obj, args, file_priv);
953 	} else {
954 		ret = i915_gem_shmem_pwrite_fast(dev, obj, args, file_priv);
955 		if (ret == -EFAULT) {
956 			ret = i915_gem_shmem_pwrite_slow(dev, obj, args,
957 							 file_priv);
958 		}
959 	}
960 
961 #if WATCH_PWRITE
962 	if (ret)
963 		DRM_INFO("pwrite failed %d\n", ret);
964 #endif
965 
966 	drm_gem_object_unreference_unlocked(obj);
967 
968 	return ret;
969 }
970 
971 /**
972  * Called when user space prepares to use an object with the CPU, either
973  * through the mmap ioctl's mapping or a GTT mapping.
974  */
975 int
976 i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
977 			  struct drm_file *file_priv)
978 {
979 	struct drm_i915_private *dev_priv = dev->dev_private;
980 	struct drm_i915_gem_set_domain *args = data;
981 	struct drm_gem_object *obj;
982 	struct drm_i915_gem_object *obj_priv;
983 	uint32_t read_domains = args->read_domains;
984 	uint32_t write_domain = args->write_domain;
985 	int ret;
986 
987 	if (!(dev->driver->driver_features & DRIVER_GEM))
988 		return -ENODEV;
989 
990 	/* Only handle setting domains to types used by the CPU. */
991 	if (write_domain & I915_GEM_GPU_DOMAINS)
992 		return -EINVAL;
993 
994 	if (read_domains & I915_GEM_GPU_DOMAINS)
995 		return -EINVAL;
996 
997 	/* Having something in the write domain implies it's in the read
998 	 * domain, and only that read domain.  Enforce that in the request.
999 	 */
1000 	if (write_domain != 0 && read_domains != write_domain)
1001 		return -EINVAL;
1002 
1003 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
1004 	if (obj == NULL)
1005 		return -EBADF;
1006 	obj_priv = to_intel_bo(obj);
1007 
1008 	mutex_lock(&dev->struct_mutex);
1009 
1010 	intel_mark_busy(dev, obj);
1011 
1012 #if WATCH_BUF
1013 	DRM_INFO("set_domain_ioctl %p(%zd), %08x %08x\n",
1014 		 obj, obj->size, read_domains, write_domain);
1015 #endif
1016 	if (read_domains & I915_GEM_DOMAIN_GTT) {
1017 		ret = i915_gem_object_set_to_gtt_domain(obj, write_domain != 0);
1018 
1019 		/* Update the LRU on the fence for the CPU access that's
1020 		 * about to occur.
1021 		 */
1022 		if (obj_priv->fence_reg != I915_FENCE_REG_NONE) {
1023 			struct drm_i915_fence_reg *reg =
1024 				&dev_priv->fence_regs[obj_priv->fence_reg];
1025 			list_move_tail(&reg->lru_list,
1026 				       &dev_priv->mm.fence_list);
1027 		}
1028 
1029 		/* Silently promote "you're not bound, there was nothing to do"
1030 		 * to success, since the client was just asking us to
1031 		 * make sure everything was done.
1032 		 */
1033 		if (ret == -EINVAL)
1034 			ret = 0;
1035 	} else {
1036 		ret = i915_gem_object_set_to_cpu_domain(obj, write_domain != 0);
1037 	}
1038 
1039 	drm_gem_object_unreference(obj);
1040 	mutex_unlock(&dev->struct_mutex);
1041 	return ret;
1042 }
1043 
1044 /**
1045  * Called when user space has done writes to this buffer
1046  */
1047 int
1048 i915_gem_sw_finish_ioctl(struct drm_device *dev, void *data,
1049 		      struct drm_file *file_priv)
1050 {
1051 	struct drm_i915_gem_sw_finish *args = data;
1052 	struct drm_gem_object *obj;
1053 	struct drm_i915_gem_object *obj_priv;
1054 	int ret = 0;
1055 
1056 	if (!(dev->driver->driver_features & DRIVER_GEM))
1057 		return -ENODEV;
1058 
1059 	mutex_lock(&dev->struct_mutex);
1060 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
1061 	if (obj == NULL) {
1062 		mutex_unlock(&dev->struct_mutex);
1063 		return -EBADF;
1064 	}
1065 
1066 #if WATCH_BUF
1067 	DRM_INFO("%s: sw_finish %d (%p %zd)\n",
1068 		 __func__, args->handle, obj, obj->size);
1069 #endif
1070 	obj_priv = to_intel_bo(obj);
1071 
1072 	/* Pinned buffers may be scanout, so flush the cache */
1073 	if (obj_priv->pin_count)
1074 		i915_gem_object_flush_cpu_write_domain(obj);
1075 
1076 	drm_gem_object_unreference(obj);
1077 	mutex_unlock(&dev->struct_mutex);
1078 	return ret;
1079 }
1080 
1081 /**
1082  * Maps the contents of an object, returning the address it is mapped
1083  * into.
1084  *
1085  * While the mapping holds a reference on the contents of the object, it doesn't
1086  * imply a ref on the object itself.
1087  */
1088 int
1089 i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
1090 		   struct drm_file *file_priv)
1091 {
1092 	struct drm_i915_gem_mmap *args = data;
1093 	struct drm_gem_object *obj;
1094 	loff_t offset;
1095 	unsigned long addr;
1096 
1097 	if (!(dev->driver->driver_features & DRIVER_GEM))
1098 		return -ENODEV;
1099 
1100 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
1101 	if (obj == NULL)
1102 		return -EBADF;
1103 
1104 	offset = args->offset;
1105 
1106 	down_write(&current->mm->mmap_sem);
1107 	addr = do_mmap(obj->filp, 0, args->size,
1108 		       PROT_READ | PROT_WRITE, MAP_SHARED,
1109 		       args->offset);
1110 	up_write(&current->mm->mmap_sem);
1111 	drm_gem_object_unreference_unlocked(obj);
1112 	if (IS_ERR((void *)addr))
1113 		return addr;
1114 
1115 	args->addr_ptr = (uint64_t) addr;
1116 
1117 	return 0;
1118 }
1119 
1120 /**
1121  * i915_gem_fault - fault a page into the GTT
1122  * vma: VMA in question
1123  * vmf: fault info
1124  *
1125  * The fault handler is set up by drm_gem_mmap() when a object is GTT mapped
1126  * from userspace.  The fault handler takes care of binding the object to
1127  * the GTT (if needed), allocating and programming a fence register (again,
1128  * only if needed based on whether the old reg is still valid or the object
1129  * is tiled) and inserting a new PTE into the faulting process.
1130  *
1131  * Note that the faulting process may involve evicting existing objects
1132  * from the GTT and/or fence registers to make room.  So performance may
1133  * suffer if the GTT working set is large or there are few fence registers
1134  * left.
1135  */
1136 int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1137 {
1138 	struct drm_gem_object *obj = vma->vm_private_data;
1139 	struct drm_device *dev = obj->dev;
1140 	struct drm_i915_private *dev_priv = dev->dev_private;
1141 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1142 	pgoff_t page_offset;
1143 	unsigned long pfn;
1144 	int ret = 0;
1145 	bool write = !!(vmf->flags & FAULT_FLAG_WRITE);
1146 
1147 	/* We don't use vmf->pgoff since that has the fake offset */
1148 	page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
1149 		PAGE_SHIFT;
1150 
1151 	/* Now bind it into the GTT if needed */
1152 	mutex_lock(&dev->struct_mutex);
1153 	if (!obj_priv->gtt_space) {
1154 		ret = i915_gem_object_bind_to_gtt(obj, 0);
1155 		if (ret)
1156 			goto unlock;
1157 
1158 		list_add_tail(&obj_priv->list, &dev_priv->mm.inactive_list);
1159 
1160 		ret = i915_gem_object_set_to_gtt_domain(obj, write);
1161 		if (ret)
1162 			goto unlock;
1163 	}
1164 
1165 	/* Need a new fence register? */
1166 	if (obj_priv->tiling_mode != I915_TILING_NONE) {
1167 		ret = i915_gem_object_get_fence_reg(obj);
1168 		if (ret)
1169 			goto unlock;
1170 	}
1171 
1172 	pfn = ((dev->agp->base + obj_priv->gtt_offset) >> PAGE_SHIFT) +
1173 		page_offset;
1174 
1175 	/* Finally, remap it using the new GTT offset */
1176 	ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn);
1177 unlock:
1178 	mutex_unlock(&dev->struct_mutex);
1179 
1180 	switch (ret) {
1181 	case 0:
1182 	case -ERESTARTSYS:
1183 		return VM_FAULT_NOPAGE;
1184 	case -ENOMEM:
1185 	case -EAGAIN:
1186 		return VM_FAULT_OOM;
1187 	default:
1188 		return VM_FAULT_SIGBUS;
1189 	}
1190 }
1191 
1192 /**
1193  * i915_gem_create_mmap_offset - create a fake mmap offset for an object
1194  * @obj: obj in question
1195  *
1196  * GEM memory mapping works by handing back to userspace a fake mmap offset
1197  * it can use in a subsequent mmap(2) call.  The DRM core code then looks
1198  * up the object based on the offset and sets up the various memory mapping
1199  * structures.
1200  *
1201  * This routine allocates and attaches a fake offset for @obj.
1202  */
1203 static int
1204 i915_gem_create_mmap_offset(struct drm_gem_object *obj)
1205 {
1206 	struct drm_device *dev = obj->dev;
1207 	struct drm_gem_mm *mm = dev->mm_private;
1208 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1209 	struct drm_map_list *list;
1210 	struct drm_local_map *map;
1211 	int ret = 0;
1212 
1213 	/* Set the object up for mmap'ing */
1214 	list = &obj->map_list;
1215 	list->map = kzalloc(sizeof(struct drm_map_list), GFP_KERNEL);
1216 	if (!list->map)
1217 		return -ENOMEM;
1218 
1219 	map = list->map;
1220 	map->type = _DRM_GEM;
1221 	map->size = obj->size;
1222 	map->handle = obj;
1223 
1224 	/* Get a DRM GEM mmap offset allocated... */
1225 	list->file_offset_node = drm_mm_search_free(&mm->offset_manager,
1226 						    obj->size / PAGE_SIZE, 0, 0);
1227 	if (!list->file_offset_node) {
1228 		DRM_ERROR("failed to allocate offset for bo %d\n", obj->name);
1229 		ret = -ENOMEM;
1230 		goto out_free_list;
1231 	}
1232 
1233 	list->file_offset_node = drm_mm_get_block(list->file_offset_node,
1234 						  obj->size / PAGE_SIZE, 0);
1235 	if (!list->file_offset_node) {
1236 		ret = -ENOMEM;
1237 		goto out_free_list;
1238 	}
1239 
1240 	list->hash.key = list->file_offset_node->start;
1241 	if (drm_ht_insert_item(&mm->offset_hash, &list->hash)) {
1242 		DRM_ERROR("failed to add to map hash\n");
1243 		ret = -ENOMEM;
1244 		goto out_free_mm;
1245 	}
1246 
1247 	/* By now we should be all set, any drm_mmap request on the offset
1248 	 * below will get to our mmap & fault handler */
1249 	obj_priv->mmap_offset = ((uint64_t) list->hash.key) << PAGE_SHIFT;
1250 
1251 	return 0;
1252 
1253 out_free_mm:
1254 	drm_mm_put_block(list->file_offset_node);
1255 out_free_list:
1256 	kfree(list->map);
1257 
1258 	return ret;
1259 }
1260 
1261 /**
1262  * i915_gem_release_mmap - remove physical page mappings
1263  * @obj: obj in question
1264  *
1265  * Preserve the reservation of the mmapping with the DRM core code, but
1266  * relinquish ownership of the pages back to the system.
1267  *
1268  * It is vital that we remove the page mapping if we have mapped a tiled
1269  * object through the GTT and then lose the fence register due to
1270  * resource pressure. Similarly if the object has been moved out of the
1271  * aperture, than pages mapped into userspace must be revoked. Removing the
1272  * mapping will then trigger a page fault on the next user access, allowing
1273  * fixup by i915_gem_fault().
1274  */
1275 void
1276 i915_gem_release_mmap(struct drm_gem_object *obj)
1277 {
1278 	struct drm_device *dev = obj->dev;
1279 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1280 
1281 	if (dev->dev_mapping)
1282 		unmap_mapping_range(dev->dev_mapping,
1283 				    obj_priv->mmap_offset, obj->size, 1);
1284 }
1285 
1286 static void
1287 i915_gem_free_mmap_offset(struct drm_gem_object *obj)
1288 {
1289 	struct drm_device *dev = obj->dev;
1290 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1291 	struct drm_gem_mm *mm = dev->mm_private;
1292 	struct drm_map_list *list;
1293 
1294 	list = &obj->map_list;
1295 	drm_ht_remove_item(&mm->offset_hash, &list->hash);
1296 
1297 	if (list->file_offset_node) {
1298 		drm_mm_put_block(list->file_offset_node);
1299 		list->file_offset_node = NULL;
1300 	}
1301 
1302 	if (list->map) {
1303 		kfree(list->map);
1304 		list->map = NULL;
1305 	}
1306 
1307 	obj_priv->mmap_offset = 0;
1308 }
1309 
1310 /**
1311  * i915_gem_get_gtt_alignment - return required GTT alignment for an object
1312  * @obj: object to check
1313  *
1314  * Return the required GTT alignment for an object, taking into account
1315  * potential fence register mapping if needed.
1316  */
1317 static uint32_t
1318 i915_gem_get_gtt_alignment(struct drm_gem_object *obj)
1319 {
1320 	struct drm_device *dev = obj->dev;
1321 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1322 	int start, i;
1323 
1324 	/*
1325 	 * Minimum alignment is 4k (GTT page size), but might be greater
1326 	 * if a fence register is needed for the object.
1327 	 */
1328 	if (IS_I965G(dev) || obj_priv->tiling_mode == I915_TILING_NONE)
1329 		return 4096;
1330 
1331 	/*
1332 	 * Previous chips need to be aligned to the size of the smallest
1333 	 * fence register that can contain the object.
1334 	 */
1335 	if (IS_I9XX(dev))
1336 		start = 1024*1024;
1337 	else
1338 		start = 512*1024;
1339 
1340 	for (i = start; i < obj->size; i <<= 1)
1341 		;
1342 
1343 	return i;
1344 }
1345 
1346 /**
1347  * i915_gem_mmap_gtt_ioctl - prepare an object for GTT mmap'ing
1348  * @dev: DRM device
1349  * @data: GTT mapping ioctl data
1350  * @file_priv: GEM object info
1351  *
1352  * Simply returns the fake offset to userspace so it can mmap it.
1353  * The mmap call will end up in drm_gem_mmap(), which will set things
1354  * up so we can get faults in the handler above.
1355  *
1356  * The fault handler will take care of binding the object into the GTT
1357  * (since it may have been evicted to make room for something), allocating
1358  * a fence register, and mapping the appropriate aperture address into
1359  * userspace.
1360  */
1361 int
1362 i915_gem_mmap_gtt_ioctl(struct drm_device *dev, void *data,
1363 			struct drm_file *file_priv)
1364 {
1365 	struct drm_i915_gem_mmap_gtt *args = data;
1366 	struct drm_i915_private *dev_priv = dev->dev_private;
1367 	struct drm_gem_object *obj;
1368 	struct drm_i915_gem_object *obj_priv;
1369 	int ret;
1370 
1371 	if (!(dev->driver->driver_features & DRIVER_GEM))
1372 		return -ENODEV;
1373 
1374 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
1375 	if (obj == NULL)
1376 		return -EBADF;
1377 
1378 	mutex_lock(&dev->struct_mutex);
1379 
1380 	obj_priv = to_intel_bo(obj);
1381 
1382 	if (obj_priv->madv != I915_MADV_WILLNEED) {
1383 		DRM_ERROR("Attempting to mmap a purgeable buffer\n");
1384 		drm_gem_object_unreference(obj);
1385 		mutex_unlock(&dev->struct_mutex);
1386 		return -EINVAL;
1387 	}
1388 
1389 
1390 	if (!obj_priv->mmap_offset) {
1391 		ret = i915_gem_create_mmap_offset(obj);
1392 		if (ret) {
1393 			drm_gem_object_unreference(obj);
1394 			mutex_unlock(&dev->struct_mutex);
1395 			return ret;
1396 		}
1397 	}
1398 
1399 	args->offset = obj_priv->mmap_offset;
1400 
1401 	/*
1402 	 * Pull it into the GTT so that we have a page list (makes the
1403 	 * initial fault faster and any subsequent flushing possible).
1404 	 */
1405 	if (!obj_priv->agp_mem) {
1406 		ret = i915_gem_object_bind_to_gtt(obj, 0);
1407 		if (ret) {
1408 			drm_gem_object_unreference(obj);
1409 			mutex_unlock(&dev->struct_mutex);
1410 			return ret;
1411 		}
1412 		list_add_tail(&obj_priv->list, &dev_priv->mm.inactive_list);
1413 	}
1414 
1415 	drm_gem_object_unreference(obj);
1416 	mutex_unlock(&dev->struct_mutex);
1417 
1418 	return 0;
1419 }
1420 
1421 void
1422 i915_gem_object_put_pages(struct drm_gem_object *obj)
1423 {
1424 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1425 	int page_count = obj->size / PAGE_SIZE;
1426 	int i;
1427 
1428 	BUG_ON(obj_priv->pages_refcount == 0);
1429 	BUG_ON(obj_priv->madv == __I915_MADV_PURGED);
1430 
1431 	if (--obj_priv->pages_refcount != 0)
1432 		return;
1433 
1434 	if (obj_priv->tiling_mode != I915_TILING_NONE)
1435 		i915_gem_object_save_bit_17_swizzle(obj);
1436 
1437 	if (obj_priv->madv == I915_MADV_DONTNEED)
1438 		obj_priv->dirty = 0;
1439 
1440 	for (i = 0; i < page_count; i++) {
1441 		if (obj_priv->dirty)
1442 			set_page_dirty(obj_priv->pages[i]);
1443 
1444 		if (obj_priv->madv == I915_MADV_WILLNEED)
1445 			mark_page_accessed(obj_priv->pages[i]);
1446 
1447 		page_cache_release(obj_priv->pages[i]);
1448 	}
1449 	obj_priv->dirty = 0;
1450 
1451 	drm_free_large(obj_priv->pages);
1452 	obj_priv->pages = NULL;
1453 }
1454 
1455 static void
1456 i915_gem_object_move_to_active(struct drm_gem_object *obj, uint32_t seqno,
1457 			       struct intel_ring_buffer *ring)
1458 {
1459 	struct drm_device *dev = obj->dev;
1460 	drm_i915_private_t *dev_priv = dev->dev_private;
1461 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1462 	BUG_ON(ring == NULL);
1463 	obj_priv->ring = ring;
1464 
1465 	/* Add a reference if we're newly entering the active list. */
1466 	if (!obj_priv->active) {
1467 		drm_gem_object_reference(obj);
1468 		obj_priv->active = 1;
1469 	}
1470 	/* Move from whatever list we were on to the tail of execution. */
1471 	spin_lock(&dev_priv->mm.active_list_lock);
1472 	list_move_tail(&obj_priv->list, &ring->active_list);
1473 	spin_unlock(&dev_priv->mm.active_list_lock);
1474 	obj_priv->last_rendering_seqno = seqno;
1475 }
1476 
1477 static void
1478 i915_gem_object_move_to_flushing(struct drm_gem_object *obj)
1479 {
1480 	struct drm_device *dev = obj->dev;
1481 	drm_i915_private_t *dev_priv = dev->dev_private;
1482 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1483 
1484 	BUG_ON(!obj_priv->active);
1485 	list_move_tail(&obj_priv->list, &dev_priv->mm.flushing_list);
1486 	obj_priv->last_rendering_seqno = 0;
1487 }
1488 
1489 /* Immediately discard the backing storage */
1490 static void
1491 i915_gem_object_truncate(struct drm_gem_object *obj)
1492 {
1493 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1494 	struct inode *inode;
1495 
1496 	inode = obj->filp->f_path.dentry->d_inode;
1497 	if (inode->i_op->truncate)
1498 		inode->i_op->truncate (inode);
1499 
1500 	obj_priv->madv = __I915_MADV_PURGED;
1501 }
1502 
1503 static inline int
1504 i915_gem_object_is_purgeable(struct drm_i915_gem_object *obj_priv)
1505 {
1506 	return obj_priv->madv == I915_MADV_DONTNEED;
1507 }
1508 
1509 static void
1510 i915_gem_object_move_to_inactive(struct drm_gem_object *obj)
1511 {
1512 	struct drm_device *dev = obj->dev;
1513 	drm_i915_private_t *dev_priv = dev->dev_private;
1514 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1515 
1516 	i915_verify_inactive(dev, __FILE__, __LINE__);
1517 	if (obj_priv->pin_count != 0)
1518 		list_del_init(&obj_priv->list);
1519 	else
1520 		list_move_tail(&obj_priv->list, &dev_priv->mm.inactive_list);
1521 
1522 	BUG_ON(!list_empty(&obj_priv->gpu_write_list));
1523 
1524 	obj_priv->last_rendering_seqno = 0;
1525 	obj_priv->ring = NULL;
1526 	if (obj_priv->active) {
1527 		obj_priv->active = 0;
1528 		drm_gem_object_unreference(obj);
1529 	}
1530 	i915_verify_inactive(dev, __FILE__, __LINE__);
1531 }
1532 
1533 static void
1534 i915_gem_process_flushing_list(struct drm_device *dev,
1535 			       uint32_t flush_domains, uint32_t seqno,
1536 			       struct intel_ring_buffer *ring)
1537 {
1538 	drm_i915_private_t *dev_priv = dev->dev_private;
1539 	struct drm_i915_gem_object *obj_priv, *next;
1540 
1541 	list_for_each_entry_safe(obj_priv, next,
1542 				 &dev_priv->mm.gpu_write_list,
1543 				 gpu_write_list) {
1544 		struct drm_gem_object *obj = &obj_priv->base;
1545 
1546 		if ((obj->write_domain & flush_domains) ==
1547 		    obj->write_domain &&
1548 		    obj_priv->ring->ring_flag == ring->ring_flag) {
1549 			uint32_t old_write_domain = obj->write_domain;
1550 
1551 			obj->write_domain = 0;
1552 			list_del_init(&obj_priv->gpu_write_list);
1553 			i915_gem_object_move_to_active(obj, seqno, ring);
1554 
1555 			/* update the fence lru list */
1556 			if (obj_priv->fence_reg != I915_FENCE_REG_NONE) {
1557 				struct drm_i915_fence_reg *reg =
1558 					&dev_priv->fence_regs[obj_priv->fence_reg];
1559 				list_move_tail(&reg->lru_list,
1560 						&dev_priv->mm.fence_list);
1561 			}
1562 
1563 			trace_i915_gem_object_change_domain(obj,
1564 							    obj->read_domains,
1565 							    old_write_domain);
1566 		}
1567 	}
1568 }
1569 
1570 uint32_t
1571 i915_add_request(struct drm_device *dev, struct drm_file *file_priv,
1572 		 uint32_t flush_domains, struct intel_ring_buffer *ring)
1573 {
1574 	drm_i915_private_t *dev_priv = dev->dev_private;
1575 	struct drm_i915_file_private *i915_file_priv = NULL;
1576 	struct drm_i915_gem_request *request;
1577 	uint32_t seqno;
1578 	int was_empty;
1579 
1580 	if (file_priv != NULL)
1581 		i915_file_priv = file_priv->driver_priv;
1582 
1583 	request = kzalloc(sizeof(*request), GFP_KERNEL);
1584 	if (request == NULL)
1585 		return 0;
1586 
1587 	seqno = ring->add_request(dev, ring, file_priv, flush_domains);
1588 
1589 	request->seqno = seqno;
1590 	request->ring = ring;
1591 	request->emitted_jiffies = jiffies;
1592 	was_empty = list_empty(&ring->request_list);
1593 	list_add_tail(&request->list, &ring->request_list);
1594 
1595 	if (i915_file_priv) {
1596 		list_add_tail(&request->client_list,
1597 			      &i915_file_priv->mm.request_list);
1598 	} else {
1599 		INIT_LIST_HEAD(&request->client_list);
1600 	}
1601 
1602 	/* Associate any objects on the flushing list matching the write
1603 	 * domain we're flushing with our flush.
1604 	 */
1605 	if (flush_domains != 0)
1606 		i915_gem_process_flushing_list(dev, flush_domains, seqno, ring);
1607 
1608 	if (!dev_priv->mm.suspended) {
1609 		mod_timer(&dev_priv->hangcheck_timer, jiffies + DRM_I915_HANGCHECK_PERIOD);
1610 		if (was_empty)
1611 			queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, HZ);
1612 	}
1613 	return seqno;
1614 }
1615 
1616 /**
1617  * Command execution barrier
1618  *
1619  * Ensures that all commands in the ring are finished
1620  * before signalling the CPU
1621  */
1622 static uint32_t
1623 i915_retire_commands(struct drm_device *dev, struct intel_ring_buffer *ring)
1624 {
1625 	uint32_t flush_domains = 0;
1626 
1627 	/* The sampler always gets flushed on i965 (sigh) */
1628 	if (IS_I965G(dev))
1629 		flush_domains |= I915_GEM_DOMAIN_SAMPLER;
1630 
1631 	ring->flush(dev, ring,
1632 			I915_GEM_DOMAIN_COMMAND, flush_domains);
1633 	return flush_domains;
1634 }
1635 
1636 /**
1637  * Moves buffers associated only with the given active seqno from the active
1638  * to inactive list, potentially freeing them.
1639  */
1640 static void
1641 i915_gem_retire_request(struct drm_device *dev,
1642 			struct drm_i915_gem_request *request)
1643 {
1644 	drm_i915_private_t *dev_priv = dev->dev_private;
1645 
1646 	trace_i915_gem_request_retire(dev, request->seqno);
1647 
1648 	/* Move any buffers on the active list that are no longer referenced
1649 	 * by the ringbuffer to the flushing/inactive lists as appropriate.
1650 	 */
1651 	spin_lock(&dev_priv->mm.active_list_lock);
1652 	while (!list_empty(&request->ring->active_list)) {
1653 		struct drm_gem_object *obj;
1654 		struct drm_i915_gem_object *obj_priv;
1655 
1656 		obj_priv = list_first_entry(&request->ring->active_list,
1657 					    struct drm_i915_gem_object,
1658 					    list);
1659 		obj = &obj_priv->base;
1660 
1661 		/* If the seqno being retired doesn't match the oldest in the
1662 		 * list, then the oldest in the list must still be newer than
1663 		 * this seqno.
1664 		 */
1665 		if (obj_priv->last_rendering_seqno != request->seqno)
1666 			goto out;
1667 
1668 #if WATCH_LRU
1669 		DRM_INFO("%s: retire %d moves to inactive list %p\n",
1670 			 __func__, request->seqno, obj);
1671 #endif
1672 
1673 		if (obj->write_domain != 0)
1674 			i915_gem_object_move_to_flushing(obj);
1675 		else {
1676 			/* Take a reference on the object so it won't be
1677 			 * freed while the spinlock is held.  The list
1678 			 * protection for this spinlock is safe when breaking
1679 			 * the lock like this since the next thing we do
1680 			 * is just get the head of the list again.
1681 			 */
1682 			drm_gem_object_reference(obj);
1683 			i915_gem_object_move_to_inactive(obj);
1684 			spin_unlock(&dev_priv->mm.active_list_lock);
1685 			drm_gem_object_unreference(obj);
1686 			spin_lock(&dev_priv->mm.active_list_lock);
1687 		}
1688 	}
1689 out:
1690 	spin_unlock(&dev_priv->mm.active_list_lock);
1691 }
1692 
1693 /**
1694  * Returns true if seq1 is later than seq2.
1695  */
1696 bool
1697 i915_seqno_passed(uint32_t seq1, uint32_t seq2)
1698 {
1699 	return (int32_t)(seq1 - seq2) >= 0;
1700 }
1701 
1702 uint32_t
1703 i915_get_gem_seqno(struct drm_device *dev,
1704 		   struct intel_ring_buffer *ring)
1705 {
1706 	return ring->get_gem_seqno(dev, ring);
1707 }
1708 
1709 /**
1710  * This function clears the request list as sequence numbers are passed.
1711  */
1712 void
1713 i915_gem_retire_requests(struct drm_device *dev,
1714 		struct intel_ring_buffer *ring)
1715 {
1716 	drm_i915_private_t *dev_priv = dev->dev_private;
1717 	uint32_t seqno;
1718 
1719 	if (!ring->status_page.page_addr
1720 			|| list_empty(&ring->request_list))
1721 		return;
1722 
1723 	seqno = i915_get_gem_seqno(dev, ring);
1724 
1725 	while (!list_empty(&ring->request_list)) {
1726 		struct drm_i915_gem_request *request;
1727 		uint32_t retiring_seqno;
1728 
1729 		request = list_first_entry(&ring->request_list,
1730 					   struct drm_i915_gem_request,
1731 					   list);
1732 		retiring_seqno = request->seqno;
1733 
1734 		if (i915_seqno_passed(seqno, retiring_seqno) ||
1735 		    atomic_read(&dev_priv->mm.wedged)) {
1736 			i915_gem_retire_request(dev, request);
1737 
1738 			list_del(&request->list);
1739 			list_del(&request->client_list);
1740 			kfree(request);
1741 		} else
1742 			break;
1743 	}
1744 
1745 	if (unlikely (dev_priv->trace_irq_seqno &&
1746 		      i915_seqno_passed(dev_priv->trace_irq_seqno, seqno))) {
1747 
1748 		ring->user_irq_put(dev, ring);
1749 		dev_priv->trace_irq_seqno = 0;
1750 	}
1751 }
1752 
1753 void
1754 i915_gem_retire_work_handler(struct work_struct *work)
1755 {
1756 	drm_i915_private_t *dev_priv;
1757 	struct drm_device *dev;
1758 
1759 	dev_priv = container_of(work, drm_i915_private_t,
1760 				mm.retire_work.work);
1761 	dev = dev_priv->dev;
1762 
1763 	mutex_lock(&dev->struct_mutex);
1764 	i915_gem_retire_requests(dev, &dev_priv->render_ring);
1765 
1766 	if (HAS_BSD(dev))
1767 		i915_gem_retire_requests(dev, &dev_priv->bsd_ring);
1768 
1769 	if (!dev_priv->mm.suspended &&
1770 		(!list_empty(&dev_priv->render_ring.request_list) ||
1771 			(HAS_BSD(dev) &&
1772 			 !list_empty(&dev_priv->bsd_ring.request_list))))
1773 		queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, HZ);
1774 	mutex_unlock(&dev->struct_mutex);
1775 }
1776 
1777 int
1778 i915_do_wait_request(struct drm_device *dev, uint32_t seqno,
1779 		int interruptible, struct intel_ring_buffer *ring)
1780 {
1781 	drm_i915_private_t *dev_priv = dev->dev_private;
1782 	u32 ier;
1783 	int ret = 0;
1784 
1785 	BUG_ON(seqno == 0);
1786 
1787 	if (atomic_read(&dev_priv->mm.wedged))
1788 		return -EIO;
1789 
1790 	if (!i915_seqno_passed(ring->get_gem_seqno(dev, ring), seqno)) {
1791 		if (HAS_PCH_SPLIT(dev))
1792 			ier = I915_READ(DEIER) | I915_READ(GTIER);
1793 		else
1794 			ier = I915_READ(IER);
1795 		if (!ier) {
1796 			DRM_ERROR("something (likely vbetool) disabled "
1797 				  "interrupts, re-enabling\n");
1798 			i915_driver_irq_preinstall(dev);
1799 			i915_driver_irq_postinstall(dev);
1800 		}
1801 
1802 		trace_i915_gem_request_wait_begin(dev, seqno);
1803 
1804 		ring->waiting_gem_seqno = seqno;
1805 		ring->user_irq_get(dev, ring);
1806 		if (interruptible)
1807 			ret = wait_event_interruptible(ring->irq_queue,
1808 				i915_seqno_passed(
1809 					ring->get_gem_seqno(dev, ring), seqno)
1810 				|| atomic_read(&dev_priv->mm.wedged));
1811 		else
1812 			wait_event(ring->irq_queue,
1813 				i915_seqno_passed(
1814 					ring->get_gem_seqno(dev, ring), seqno)
1815 				|| atomic_read(&dev_priv->mm.wedged));
1816 
1817 		ring->user_irq_put(dev, ring);
1818 		ring->waiting_gem_seqno = 0;
1819 
1820 		trace_i915_gem_request_wait_end(dev, seqno);
1821 	}
1822 	if (atomic_read(&dev_priv->mm.wedged))
1823 		ret = -EIO;
1824 
1825 	if (ret && ret != -ERESTARTSYS)
1826 		DRM_ERROR("%s returns %d (awaiting %d at %d)\n",
1827 			  __func__, ret, seqno, ring->get_gem_seqno(dev, ring));
1828 
1829 	/* Directly dispatch request retiring.  While we have the work queue
1830 	 * to handle this, the waiter on a request often wants an associated
1831 	 * buffer to have made it to the inactive list, and we would need
1832 	 * a separate wait queue to handle that.
1833 	 */
1834 	if (ret == 0)
1835 		i915_gem_retire_requests(dev, ring);
1836 
1837 	return ret;
1838 }
1839 
1840 /**
1841  * Waits for a sequence number to be signaled, and cleans up the
1842  * request and object lists appropriately for that event.
1843  */
1844 static int
1845 i915_wait_request(struct drm_device *dev, uint32_t seqno,
1846 		struct intel_ring_buffer *ring)
1847 {
1848 	return i915_do_wait_request(dev, seqno, 1, ring);
1849 }
1850 
1851 static void
1852 i915_gem_flush(struct drm_device *dev,
1853 	       uint32_t invalidate_domains,
1854 	       uint32_t flush_domains)
1855 {
1856 	drm_i915_private_t *dev_priv = dev->dev_private;
1857 	if (flush_domains & I915_GEM_DOMAIN_CPU)
1858 		drm_agp_chipset_flush(dev);
1859 	dev_priv->render_ring.flush(dev, &dev_priv->render_ring,
1860 			invalidate_domains,
1861 			flush_domains);
1862 
1863 	if (HAS_BSD(dev))
1864 		dev_priv->bsd_ring.flush(dev, &dev_priv->bsd_ring,
1865 				invalidate_domains,
1866 				flush_domains);
1867 }
1868 
1869 static void
1870 i915_gem_flush_ring(struct drm_device *dev,
1871 	       uint32_t invalidate_domains,
1872 	       uint32_t flush_domains,
1873 	       struct intel_ring_buffer *ring)
1874 {
1875 	if (flush_domains & I915_GEM_DOMAIN_CPU)
1876 		drm_agp_chipset_flush(dev);
1877 	ring->flush(dev, ring,
1878 			invalidate_domains,
1879 			flush_domains);
1880 }
1881 
1882 /**
1883  * Ensures that all rendering to the object has completed and the object is
1884  * safe to unbind from the GTT or access from the CPU.
1885  */
1886 static int
1887 i915_gem_object_wait_rendering(struct drm_gem_object *obj)
1888 {
1889 	struct drm_device *dev = obj->dev;
1890 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1891 	int ret;
1892 
1893 	/* This function only exists to support waiting for existing rendering,
1894 	 * not for emitting required flushes.
1895 	 */
1896 	BUG_ON((obj->write_domain & I915_GEM_GPU_DOMAINS) != 0);
1897 
1898 	/* If there is rendering queued on the buffer being evicted, wait for
1899 	 * it.
1900 	 */
1901 	if (obj_priv->active) {
1902 #if WATCH_BUF
1903 		DRM_INFO("%s: object %p wait for seqno %08x\n",
1904 			  __func__, obj, obj_priv->last_rendering_seqno);
1905 #endif
1906 		ret = i915_wait_request(dev,
1907 				obj_priv->last_rendering_seqno, obj_priv->ring);
1908 		if (ret != 0)
1909 			return ret;
1910 	}
1911 
1912 	return 0;
1913 }
1914 
1915 /**
1916  * Unbinds an object from the GTT aperture.
1917  */
1918 int
1919 i915_gem_object_unbind(struct drm_gem_object *obj)
1920 {
1921 	struct drm_device *dev = obj->dev;
1922 	drm_i915_private_t *dev_priv = dev->dev_private;
1923 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
1924 	int ret = 0;
1925 
1926 #if WATCH_BUF
1927 	DRM_INFO("%s:%d %p\n", __func__, __LINE__, obj);
1928 	DRM_INFO("gtt_space %p\n", obj_priv->gtt_space);
1929 #endif
1930 	if (obj_priv->gtt_space == NULL)
1931 		return 0;
1932 
1933 	if (obj_priv->pin_count != 0) {
1934 		DRM_ERROR("Attempting to unbind pinned buffer\n");
1935 		return -EINVAL;
1936 	}
1937 
1938 	/* blow away mappings if mapped through GTT */
1939 	i915_gem_release_mmap(obj);
1940 
1941 	/* Move the object to the CPU domain to ensure that
1942 	 * any possible CPU writes while it's not in the GTT
1943 	 * are flushed when we go to remap it. This will
1944 	 * also ensure that all pending GPU writes are finished
1945 	 * before we unbind.
1946 	 */
1947 	ret = i915_gem_object_set_to_cpu_domain(obj, 1);
1948 	if (ret) {
1949 		if (ret != -ERESTARTSYS)
1950 			DRM_ERROR("set_domain failed: %d\n", ret);
1951 		return ret;
1952 	}
1953 
1954 	BUG_ON(obj_priv->active);
1955 
1956 	/* release the fence reg _after_ flushing */
1957 	if (obj_priv->fence_reg != I915_FENCE_REG_NONE)
1958 		i915_gem_clear_fence_reg(obj);
1959 
1960 	if (obj_priv->agp_mem != NULL) {
1961 		drm_unbind_agp(obj_priv->agp_mem);
1962 		drm_free_agp(obj_priv->agp_mem, obj->size / PAGE_SIZE);
1963 		obj_priv->agp_mem = NULL;
1964 	}
1965 
1966 	i915_gem_object_put_pages(obj);
1967 	BUG_ON(obj_priv->pages_refcount);
1968 
1969 	if (obj_priv->gtt_space) {
1970 		atomic_dec(&dev->gtt_count);
1971 		atomic_sub(obj->size, &dev->gtt_memory);
1972 
1973 		drm_mm_put_block(obj_priv->gtt_space);
1974 		obj_priv->gtt_space = NULL;
1975 	}
1976 
1977 	/* Remove ourselves from the LRU list if present. */
1978 	spin_lock(&dev_priv->mm.active_list_lock);
1979 	if (!list_empty(&obj_priv->list))
1980 		list_del_init(&obj_priv->list);
1981 	spin_unlock(&dev_priv->mm.active_list_lock);
1982 
1983 	if (i915_gem_object_is_purgeable(obj_priv))
1984 		i915_gem_object_truncate(obj);
1985 
1986 	trace_i915_gem_object_unbind(obj);
1987 
1988 	return 0;
1989 }
1990 
1991 static struct drm_gem_object *
1992 i915_gem_find_inactive_object(struct drm_device *dev, int min_size)
1993 {
1994 	drm_i915_private_t *dev_priv = dev->dev_private;
1995 	struct drm_i915_gem_object *obj_priv;
1996 	struct drm_gem_object *best = NULL;
1997 	struct drm_gem_object *first = NULL;
1998 
1999 	/* Try to find the smallest clean object */
2000 	list_for_each_entry(obj_priv, &dev_priv->mm.inactive_list, list) {
2001 		struct drm_gem_object *obj = &obj_priv->base;
2002 		if (obj->size >= min_size) {
2003 			if ((!obj_priv->dirty ||
2004 			     i915_gem_object_is_purgeable(obj_priv)) &&
2005 			    (!best || obj->size < best->size)) {
2006 				best = obj;
2007 				if (best->size == min_size)
2008 					return best;
2009 			}
2010 			if (!first)
2011 			    first = obj;
2012 		}
2013 	}
2014 
2015 	return best ? best : first;
2016 }
2017 
2018 static int
2019 i915_gpu_idle(struct drm_device *dev)
2020 {
2021 	drm_i915_private_t *dev_priv = dev->dev_private;
2022 	bool lists_empty;
2023 	uint32_t seqno1, seqno2;
2024 	int ret;
2025 
2026 	spin_lock(&dev_priv->mm.active_list_lock);
2027 	lists_empty = (list_empty(&dev_priv->mm.flushing_list) &&
2028 		       list_empty(&dev_priv->render_ring.active_list) &&
2029 		       (!HAS_BSD(dev) ||
2030 			list_empty(&dev_priv->bsd_ring.active_list)));
2031 	spin_unlock(&dev_priv->mm.active_list_lock);
2032 
2033 	if (lists_empty)
2034 		return 0;
2035 
2036 	/* Flush everything onto the inactive list. */
2037 	i915_gem_flush(dev, I915_GEM_GPU_DOMAINS, I915_GEM_GPU_DOMAINS);
2038 	seqno1 = i915_add_request(dev, NULL, I915_GEM_GPU_DOMAINS,
2039 			&dev_priv->render_ring);
2040 	if (seqno1 == 0)
2041 		return -ENOMEM;
2042 	ret = i915_wait_request(dev, seqno1, &dev_priv->render_ring);
2043 
2044 	if (HAS_BSD(dev)) {
2045 		seqno2 = i915_add_request(dev, NULL, I915_GEM_GPU_DOMAINS,
2046 				&dev_priv->bsd_ring);
2047 		if (seqno2 == 0)
2048 			return -ENOMEM;
2049 
2050 		ret = i915_wait_request(dev, seqno2, &dev_priv->bsd_ring);
2051 		if (ret)
2052 			return ret;
2053 	}
2054 
2055 
2056 	return ret;
2057 }
2058 
2059 static int
2060 i915_gem_evict_everything(struct drm_device *dev)
2061 {
2062 	drm_i915_private_t *dev_priv = dev->dev_private;
2063 	int ret;
2064 	bool lists_empty;
2065 
2066 	spin_lock(&dev_priv->mm.active_list_lock);
2067 	lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
2068 		       list_empty(&dev_priv->mm.flushing_list) &&
2069 		       list_empty(&dev_priv->render_ring.active_list) &&
2070 		       (!HAS_BSD(dev)
2071 			|| list_empty(&dev_priv->bsd_ring.active_list)));
2072 	spin_unlock(&dev_priv->mm.active_list_lock);
2073 
2074 	if (lists_empty)
2075 		return -ENOSPC;
2076 
2077 	/* Flush everything (on to the inactive lists) and evict */
2078 	ret = i915_gpu_idle(dev);
2079 	if (ret)
2080 		return ret;
2081 
2082 	BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
2083 
2084 	ret = i915_gem_evict_from_inactive_list(dev);
2085 	if (ret)
2086 		return ret;
2087 
2088 	spin_lock(&dev_priv->mm.active_list_lock);
2089 	lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
2090 		       list_empty(&dev_priv->mm.flushing_list) &&
2091 		       list_empty(&dev_priv->render_ring.active_list) &&
2092 		       (!HAS_BSD(dev)
2093 			|| list_empty(&dev_priv->bsd_ring.active_list)));
2094 	spin_unlock(&dev_priv->mm.active_list_lock);
2095 	BUG_ON(!lists_empty);
2096 
2097 	return 0;
2098 }
2099 
2100 static int
2101 i915_gem_evict_something(struct drm_device *dev, int min_size)
2102 {
2103 	drm_i915_private_t *dev_priv = dev->dev_private;
2104 	struct drm_gem_object *obj;
2105 	int ret;
2106 
2107 	struct intel_ring_buffer *render_ring = &dev_priv->render_ring;
2108 	struct intel_ring_buffer *bsd_ring = &dev_priv->bsd_ring;
2109 	for (;;) {
2110 		i915_gem_retire_requests(dev, render_ring);
2111 
2112 		if (HAS_BSD(dev))
2113 			i915_gem_retire_requests(dev, bsd_ring);
2114 
2115 		/* If there's an inactive buffer available now, grab it
2116 		 * and be done.
2117 		 */
2118 		obj = i915_gem_find_inactive_object(dev, min_size);
2119 		if (obj) {
2120 			struct drm_i915_gem_object *obj_priv;
2121 
2122 #if WATCH_LRU
2123 			DRM_INFO("%s: evicting %p\n", __func__, obj);
2124 #endif
2125 			obj_priv = to_intel_bo(obj);
2126 			BUG_ON(obj_priv->pin_count != 0);
2127 			BUG_ON(obj_priv->active);
2128 
2129 			/* Wait on the rendering and unbind the buffer. */
2130 			return i915_gem_object_unbind(obj);
2131 		}
2132 
2133 		/* If we didn't get anything, but the ring is still processing
2134 		 * things, wait for the next to finish and hopefully leave us
2135 		 * a buffer to evict.
2136 		 */
2137 		if (!list_empty(&render_ring->request_list)) {
2138 			struct drm_i915_gem_request *request;
2139 
2140 			request = list_first_entry(&render_ring->request_list,
2141 						   struct drm_i915_gem_request,
2142 						   list);
2143 
2144 			ret = i915_wait_request(dev,
2145 					request->seqno, request->ring);
2146 			if (ret)
2147 				return ret;
2148 
2149 			continue;
2150 		}
2151 
2152 		if (HAS_BSD(dev) && !list_empty(&bsd_ring->request_list)) {
2153 			struct drm_i915_gem_request *request;
2154 
2155 			request = list_first_entry(&bsd_ring->request_list,
2156 						   struct drm_i915_gem_request,
2157 						   list);
2158 
2159 			ret = i915_wait_request(dev,
2160 					request->seqno, request->ring);
2161 			if (ret)
2162 				return ret;
2163 
2164 			continue;
2165 		}
2166 
2167 		/* If we didn't have anything on the request list but there
2168 		 * are buffers awaiting a flush, emit one and try again.
2169 		 * When we wait on it, those buffers waiting for that flush
2170 		 * will get moved to inactive.
2171 		 */
2172 		if (!list_empty(&dev_priv->mm.flushing_list)) {
2173 			struct drm_i915_gem_object *obj_priv;
2174 
2175 			/* Find an object that we can immediately reuse */
2176 			list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, list) {
2177 				obj = &obj_priv->base;
2178 				if (obj->size >= min_size)
2179 					break;
2180 
2181 				obj = NULL;
2182 			}
2183 
2184 			if (obj != NULL) {
2185 				uint32_t seqno;
2186 
2187 				i915_gem_flush_ring(dev,
2188 					       obj->write_domain,
2189 					       obj->write_domain,
2190 					       obj_priv->ring);
2191 				seqno = i915_add_request(dev, NULL,
2192 						obj->write_domain,
2193 						obj_priv->ring);
2194 				if (seqno == 0)
2195 					return -ENOMEM;
2196 				continue;
2197 			}
2198 		}
2199 
2200 		/* If we didn't do any of the above, there's no single buffer
2201 		 * large enough to swap out for the new one, so just evict
2202 		 * everything and start again. (This should be rare.)
2203 		 */
2204 		if (!list_empty (&dev_priv->mm.inactive_list))
2205 			return i915_gem_evict_from_inactive_list(dev);
2206 		else
2207 			return i915_gem_evict_everything(dev);
2208 	}
2209 }
2210 
2211 int
2212 i915_gem_object_get_pages(struct drm_gem_object *obj,
2213 			  gfp_t gfpmask)
2214 {
2215 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2216 	int page_count, i;
2217 	struct address_space *mapping;
2218 	struct inode *inode;
2219 	struct page *page;
2220 
2221 	BUG_ON(obj_priv->pages_refcount
2222 			== DRM_I915_GEM_OBJECT_MAX_PAGES_REFCOUNT);
2223 
2224 	if (obj_priv->pages_refcount++ != 0)
2225 		return 0;
2226 
2227 	/* Get the list of pages out of our struct file.  They'll be pinned
2228 	 * at this point until we release them.
2229 	 */
2230 	page_count = obj->size / PAGE_SIZE;
2231 	BUG_ON(obj_priv->pages != NULL);
2232 	obj_priv->pages = drm_calloc_large(page_count, sizeof(struct page *));
2233 	if (obj_priv->pages == NULL) {
2234 		obj_priv->pages_refcount--;
2235 		return -ENOMEM;
2236 	}
2237 
2238 	inode = obj->filp->f_path.dentry->d_inode;
2239 	mapping = inode->i_mapping;
2240 	for (i = 0; i < page_count; i++) {
2241 		page = read_cache_page_gfp(mapping, i,
2242 					   mapping_gfp_mask (mapping) |
2243 					   __GFP_COLD |
2244 					   gfpmask);
2245 		if (IS_ERR(page))
2246 			goto err_pages;
2247 
2248 		obj_priv->pages[i] = page;
2249 	}
2250 
2251 	if (obj_priv->tiling_mode != I915_TILING_NONE)
2252 		i915_gem_object_do_bit_17_swizzle(obj);
2253 
2254 	return 0;
2255 
2256 err_pages:
2257 	while (i--)
2258 		page_cache_release(obj_priv->pages[i]);
2259 
2260 	drm_free_large(obj_priv->pages);
2261 	obj_priv->pages = NULL;
2262 	obj_priv->pages_refcount--;
2263 	return PTR_ERR(page);
2264 }
2265 
2266 static void sandybridge_write_fence_reg(struct drm_i915_fence_reg *reg)
2267 {
2268 	struct drm_gem_object *obj = reg->obj;
2269 	struct drm_device *dev = obj->dev;
2270 	drm_i915_private_t *dev_priv = dev->dev_private;
2271 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2272 	int regnum = obj_priv->fence_reg;
2273 	uint64_t val;
2274 
2275 	val = (uint64_t)((obj_priv->gtt_offset + obj->size - 4096) &
2276 		    0xfffff000) << 32;
2277 	val |= obj_priv->gtt_offset & 0xfffff000;
2278 	val |= (uint64_t)((obj_priv->stride / 128) - 1) <<
2279 		SANDYBRIDGE_FENCE_PITCH_SHIFT;
2280 
2281 	if (obj_priv->tiling_mode == I915_TILING_Y)
2282 		val |= 1 << I965_FENCE_TILING_Y_SHIFT;
2283 	val |= I965_FENCE_REG_VALID;
2284 
2285 	I915_WRITE64(FENCE_REG_SANDYBRIDGE_0 + (regnum * 8), val);
2286 }
2287 
2288 static void i965_write_fence_reg(struct drm_i915_fence_reg *reg)
2289 {
2290 	struct drm_gem_object *obj = reg->obj;
2291 	struct drm_device *dev = obj->dev;
2292 	drm_i915_private_t *dev_priv = dev->dev_private;
2293 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2294 	int regnum = obj_priv->fence_reg;
2295 	uint64_t val;
2296 
2297 	val = (uint64_t)((obj_priv->gtt_offset + obj->size - 4096) &
2298 		    0xfffff000) << 32;
2299 	val |= obj_priv->gtt_offset & 0xfffff000;
2300 	val |= ((obj_priv->stride / 128) - 1) << I965_FENCE_PITCH_SHIFT;
2301 	if (obj_priv->tiling_mode == I915_TILING_Y)
2302 		val |= 1 << I965_FENCE_TILING_Y_SHIFT;
2303 	val |= I965_FENCE_REG_VALID;
2304 
2305 	I915_WRITE64(FENCE_REG_965_0 + (regnum * 8), val);
2306 }
2307 
2308 static void i915_write_fence_reg(struct drm_i915_fence_reg *reg)
2309 {
2310 	struct drm_gem_object *obj = reg->obj;
2311 	struct drm_device *dev = obj->dev;
2312 	drm_i915_private_t *dev_priv = dev->dev_private;
2313 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2314 	int regnum = obj_priv->fence_reg;
2315 	int tile_width;
2316 	uint32_t fence_reg, val;
2317 	uint32_t pitch_val;
2318 
2319 	if ((obj_priv->gtt_offset & ~I915_FENCE_START_MASK) ||
2320 	    (obj_priv->gtt_offset & (obj->size - 1))) {
2321 		WARN(1, "%s: object 0x%08x not 1M or size (0x%zx) aligned\n",
2322 		     __func__, obj_priv->gtt_offset, obj->size);
2323 		return;
2324 	}
2325 
2326 	if (obj_priv->tiling_mode == I915_TILING_Y &&
2327 	    HAS_128_BYTE_Y_TILING(dev))
2328 		tile_width = 128;
2329 	else
2330 		tile_width = 512;
2331 
2332 	/* Note: pitch better be a power of two tile widths */
2333 	pitch_val = obj_priv->stride / tile_width;
2334 	pitch_val = ffs(pitch_val) - 1;
2335 
2336 	if (obj_priv->tiling_mode == I915_TILING_Y &&
2337 	    HAS_128_BYTE_Y_TILING(dev))
2338 		WARN_ON(pitch_val > I830_FENCE_MAX_PITCH_VAL);
2339 	else
2340 		WARN_ON(pitch_val > I915_FENCE_MAX_PITCH_VAL);
2341 
2342 	val = obj_priv->gtt_offset;
2343 	if (obj_priv->tiling_mode == I915_TILING_Y)
2344 		val |= 1 << I830_FENCE_TILING_Y_SHIFT;
2345 	val |= I915_FENCE_SIZE_BITS(obj->size);
2346 	val |= pitch_val << I830_FENCE_PITCH_SHIFT;
2347 	val |= I830_FENCE_REG_VALID;
2348 
2349 	if (regnum < 8)
2350 		fence_reg = FENCE_REG_830_0 + (regnum * 4);
2351 	else
2352 		fence_reg = FENCE_REG_945_8 + ((regnum - 8) * 4);
2353 	I915_WRITE(fence_reg, val);
2354 }
2355 
2356 static void i830_write_fence_reg(struct drm_i915_fence_reg *reg)
2357 {
2358 	struct drm_gem_object *obj = reg->obj;
2359 	struct drm_device *dev = obj->dev;
2360 	drm_i915_private_t *dev_priv = dev->dev_private;
2361 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2362 	int regnum = obj_priv->fence_reg;
2363 	uint32_t val;
2364 	uint32_t pitch_val;
2365 	uint32_t fence_size_bits;
2366 
2367 	if ((obj_priv->gtt_offset & ~I830_FENCE_START_MASK) ||
2368 	    (obj_priv->gtt_offset & (obj->size - 1))) {
2369 		WARN(1, "%s: object 0x%08x not 512K or size aligned\n",
2370 		     __func__, obj_priv->gtt_offset);
2371 		return;
2372 	}
2373 
2374 	pitch_val = obj_priv->stride / 128;
2375 	pitch_val = ffs(pitch_val) - 1;
2376 	WARN_ON(pitch_val > I830_FENCE_MAX_PITCH_VAL);
2377 
2378 	val = obj_priv->gtt_offset;
2379 	if (obj_priv->tiling_mode == I915_TILING_Y)
2380 		val |= 1 << I830_FENCE_TILING_Y_SHIFT;
2381 	fence_size_bits = I830_FENCE_SIZE_BITS(obj->size);
2382 	WARN_ON(fence_size_bits & ~0x00000f00);
2383 	val |= fence_size_bits;
2384 	val |= pitch_val << I830_FENCE_PITCH_SHIFT;
2385 	val |= I830_FENCE_REG_VALID;
2386 
2387 	I915_WRITE(FENCE_REG_830_0 + (regnum * 4), val);
2388 }
2389 
2390 static int i915_find_fence_reg(struct drm_device *dev)
2391 {
2392 	struct drm_i915_fence_reg *reg = NULL;
2393 	struct drm_i915_gem_object *obj_priv = NULL;
2394 	struct drm_i915_private *dev_priv = dev->dev_private;
2395 	struct drm_gem_object *obj = NULL;
2396 	int i, avail, ret;
2397 
2398 	/* First try to find a free reg */
2399 	avail = 0;
2400 	for (i = dev_priv->fence_reg_start; i < dev_priv->num_fence_regs; i++) {
2401 		reg = &dev_priv->fence_regs[i];
2402 		if (!reg->obj)
2403 			return i;
2404 
2405 		obj_priv = to_intel_bo(reg->obj);
2406 		if (!obj_priv->pin_count)
2407 		    avail++;
2408 	}
2409 
2410 	if (avail == 0)
2411 		return -ENOSPC;
2412 
2413 	/* None available, try to steal one or wait for a user to finish */
2414 	i = I915_FENCE_REG_NONE;
2415 	list_for_each_entry(reg, &dev_priv->mm.fence_list,
2416 			    lru_list) {
2417 		obj = reg->obj;
2418 		obj_priv = to_intel_bo(obj);
2419 
2420 		if (obj_priv->pin_count)
2421 			continue;
2422 
2423 		/* found one! */
2424 		i = obj_priv->fence_reg;
2425 		break;
2426 	}
2427 
2428 	BUG_ON(i == I915_FENCE_REG_NONE);
2429 
2430 	/* We only have a reference on obj from the active list. put_fence_reg
2431 	 * might drop that one, causing a use-after-free in it. So hold a
2432 	 * private reference to obj like the other callers of put_fence_reg
2433 	 * (set_tiling ioctl) do. */
2434 	drm_gem_object_reference(obj);
2435 	ret = i915_gem_object_put_fence_reg(obj);
2436 	drm_gem_object_unreference(obj);
2437 	if (ret != 0)
2438 		return ret;
2439 
2440 	return i;
2441 }
2442 
2443 /**
2444  * i915_gem_object_get_fence_reg - set up a fence reg for an object
2445  * @obj: object to map through a fence reg
2446  *
2447  * When mapping objects through the GTT, userspace wants to be able to write
2448  * to them without having to worry about swizzling if the object is tiled.
2449  *
2450  * This function walks the fence regs looking for a free one for @obj,
2451  * stealing one if it can't find any.
2452  *
2453  * It then sets up the reg based on the object's properties: address, pitch
2454  * and tiling format.
2455  */
2456 int
2457 i915_gem_object_get_fence_reg(struct drm_gem_object *obj)
2458 {
2459 	struct drm_device *dev = obj->dev;
2460 	struct drm_i915_private *dev_priv = dev->dev_private;
2461 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2462 	struct drm_i915_fence_reg *reg = NULL;
2463 	int ret;
2464 
2465 	/* Just update our place in the LRU if our fence is getting used. */
2466 	if (obj_priv->fence_reg != I915_FENCE_REG_NONE) {
2467 		reg = &dev_priv->fence_regs[obj_priv->fence_reg];
2468 		list_move_tail(&reg->lru_list, &dev_priv->mm.fence_list);
2469 		return 0;
2470 	}
2471 
2472 	switch (obj_priv->tiling_mode) {
2473 	case I915_TILING_NONE:
2474 		WARN(1, "allocating a fence for non-tiled object?\n");
2475 		break;
2476 	case I915_TILING_X:
2477 		if (!obj_priv->stride)
2478 			return -EINVAL;
2479 		WARN((obj_priv->stride & (512 - 1)),
2480 		     "object 0x%08x is X tiled but has non-512B pitch\n",
2481 		     obj_priv->gtt_offset);
2482 		break;
2483 	case I915_TILING_Y:
2484 		if (!obj_priv->stride)
2485 			return -EINVAL;
2486 		WARN((obj_priv->stride & (128 - 1)),
2487 		     "object 0x%08x is Y tiled but has non-128B pitch\n",
2488 		     obj_priv->gtt_offset);
2489 		break;
2490 	}
2491 
2492 	ret = i915_find_fence_reg(dev);
2493 	if (ret < 0)
2494 		return ret;
2495 
2496 	obj_priv->fence_reg = ret;
2497 	reg = &dev_priv->fence_regs[obj_priv->fence_reg];
2498 	list_add_tail(&reg->lru_list, &dev_priv->mm.fence_list);
2499 
2500 	reg->obj = obj;
2501 
2502 	if (IS_GEN6(dev))
2503 		sandybridge_write_fence_reg(reg);
2504 	else if (IS_I965G(dev))
2505 		i965_write_fence_reg(reg);
2506 	else if (IS_I9XX(dev))
2507 		i915_write_fence_reg(reg);
2508 	else
2509 		i830_write_fence_reg(reg);
2510 
2511 	trace_i915_gem_object_get_fence(obj, obj_priv->fence_reg,
2512 			obj_priv->tiling_mode);
2513 
2514 	return 0;
2515 }
2516 
2517 /**
2518  * i915_gem_clear_fence_reg - clear out fence register info
2519  * @obj: object to clear
2520  *
2521  * Zeroes out the fence register itself and clears out the associated
2522  * data structures in dev_priv and obj_priv.
2523  */
2524 static void
2525 i915_gem_clear_fence_reg(struct drm_gem_object *obj)
2526 {
2527 	struct drm_device *dev = obj->dev;
2528 	drm_i915_private_t *dev_priv = dev->dev_private;
2529 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2530 	struct drm_i915_fence_reg *reg =
2531 		&dev_priv->fence_regs[obj_priv->fence_reg];
2532 
2533 	if (IS_GEN6(dev)) {
2534 		I915_WRITE64(FENCE_REG_SANDYBRIDGE_0 +
2535 			     (obj_priv->fence_reg * 8), 0);
2536 	} else if (IS_I965G(dev)) {
2537 		I915_WRITE64(FENCE_REG_965_0 + (obj_priv->fence_reg * 8), 0);
2538 	} else {
2539 		uint32_t fence_reg;
2540 
2541 		if (obj_priv->fence_reg < 8)
2542 			fence_reg = FENCE_REG_830_0 + obj_priv->fence_reg * 4;
2543 		else
2544 			fence_reg = FENCE_REG_945_8 + (obj_priv->fence_reg -
2545 						       8) * 4;
2546 
2547 		I915_WRITE(fence_reg, 0);
2548 	}
2549 
2550 	reg->obj = NULL;
2551 	obj_priv->fence_reg = I915_FENCE_REG_NONE;
2552 	list_del_init(&reg->lru_list);
2553 }
2554 
2555 /**
2556  * i915_gem_object_put_fence_reg - waits on outstanding fenced access
2557  * to the buffer to finish, and then resets the fence register.
2558  * @obj: tiled object holding a fence register.
2559  *
2560  * Zeroes out the fence register itself and clears out the associated
2561  * data structures in dev_priv and obj_priv.
2562  */
2563 int
2564 i915_gem_object_put_fence_reg(struct drm_gem_object *obj)
2565 {
2566 	struct drm_device *dev = obj->dev;
2567 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2568 
2569 	if (obj_priv->fence_reg == I915_FENCE_REG_NONE)
2570 		return 0;
2571 
2572 	/* If we've changed tiling, GTT-mappings of the object
2573 	 * need to re-fault to ensure that the correct fence register
2574 	 * setup is in place.
2575 	 */
2576 	i915_gem_release_mmap(obj);
2577 
2578 	/* On the i915, GPU access to tiled buffers is via a fence,
2579 	 * therefore we must wait for any outstanding access to complete
2580 	 * before clearing the fence.
2581 	 */
2582 	if (!IS_I965G(dev)) {
2583 		int ret;
2584 
2585 		i915_gem_object_flush_gpu_write_domain(obj);
2586 		ret = i915_gem_object_wait_rendering(obj);
2587 		if (ret != 0)
2588 			return ret;
2589 	}
2590 
2591 	i915_gem_object_flush_gtt_write_domain(obj);
2592 	i915_gem_clear_fence_reg (obj);
2593 
2594 	return 0;
2595 }
2596 
2597 /**
2598  * Finds free space in the GTT aperture and binds the object there.
2599  */
2600 static int
2601 i915_gem_object_bind_to_gtt(struct drm_gem_object *obj, unsigned alignment)
2602 {
2603 	struct drm_device *dev = obj->dev;
2604 	drm_i915_private_t *dev_priv = dev->dev_private;
2605 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2606 	struct drm_mm_node *free_space;
2607 	gfp_t gfpmask =  __GFP_NORETRY | __GFP_NOWARN;
2608 	int ret;
2609 
2610 	if (obj_priv->madv != I915_MADV_WILLNEED) {
2611 		DRM_ERROR("Attempting to bind a purgeable object\n");
2612 		return -EINVAL;
2613 	}
2614 
2615 	if (alignment == 0)
2616 		alignment = i915_gem_get_gtt_alignment(obj);
2617 	if (alignment & (i915_gem_get_gtt_alignment(obj) - 1)) {
2618 		DRM_ERROR("Invalid object alignment requested %u\n", alignment);
2619 		return -EINVAL;
2620 	}
2621 
2622 	/* If the object is bigger than the entire aperture, reject it early
2623 	 * before evicting everything in a vain attempt to find space.
2624 	 */
2625 	if (obj->size > dev->gtt_total) {
2626 		DRM_ERROR("Attempting to bind an object larger than the aperture\n");
2627 		return -E2BIG;
2628 	}
2629 
2630  search_free:
2631 	free_space = drm_mm_search_free(&dev_priv->mm.gtt_space,
2632 					obj->size, alignment, 0);
2633 	if (free_space != NULL) {
2634 		obj_priv->gtt_space = drm_mm_get_block(free_space, obj->size,
2635 						       alignment);
2636 		if (obj_priv->gtt_space != NULL) {
2637 			obj_priv->gtt_space->private = obj;
2638 			obj_priv->gtt_offset = obj_priv->gtt_space->start;
2639 		}
2640 	}
2641 	if (obj_priv->gtt_space == NULL) {
2642 		/* If the gtt is empty and we're still having trouble
2643 		 * fitting our object in, we're out of memory.
2644 		 */
2645 #if WATCH_LRU
2646 		DRM_INFO("%s: GTT full, evicting something\n", __func__);
2647 #endif
2648 		ret = i915_gem_evict_something(dev, obj->size);
2649 		if (ret)
2650 			return ret;
2651 
2652 		goto search_free;
2653 	}
2654 
2655 #if WATCH_BUF
2656 	DRM_INFO("Binding object of size %zd at 0x%08x\n",
2657 		 obj->size, obj_priv->gtt_offset);
2658 #endif
2659 	ret = i915_gem_object_get_pages(obj, gfpmask);
2660 	if (ret) {
2661 		drm_mm_put_block(obj_priv->gtt_space);
2662 		obj_priv->gtt_space = NULL;
2663 
2664 		if (ret == -ENOMEM) {
2665 			/* first try to clear up some space from the GTT */
2666 			ret = i915_gem_evict_something(dev, obj->size);
2667 			if (ret) {
2668 				/* now try to shrink everyone else */
2669 				if (gfpmask) {
2670 					gfpmask = 0;
2671 					goto search_free;
2672 				}
2673 
2674 				return ret;
2675 			}
2676 
2677 			goto search_free;
2678 		}
2679 
2680 		return ret;
2681 	}
2682 
2683 	/* Create an AGP memory structure pointing at our pages, and bind it
2684 	 * into the GTT.
2685 	 */
2686 	obj_priv->agp_mem = drm_agp_bind_pages(dev,
2687 					       obj_priv->pages,
2688 					       obj->size >> PAGE_SHIFT,
2689 					       obj_priv->gtt_offset,
2690 					       obj_priv->agp_type);
2691 	if (obj_priv->agp_mem == NULL) {
2692 		i915_gem_object_put_pages(obj);
2693 		drm_mm_put_block(obj_priv->gtt_space);
2694 		obj_priv->gtt_space = NULL;
2695 
2696 		ret = i915_gem_evict_something(dev, obj->size);
2697 		if (ret)
2698 			return ret;
2699 
2700 		goto search_free;
2701 	}
2702 	atomic_inc(&dev->gtt_count);
2703 	atomic_add(obj->size, &dev->gtt_memory);
2704 
2705 	/* Assert that the object is not currently in any GPU domain. As it
2706 	 * wasn't in the GTT, there shouldn't be any way it could have been in
2707 	 * a GPU cache
2708 	 */
2709 	BUG_ON(obj->read_domains & I915_GEM_GPU_DOMAINS);
2710 	BUG_ON(obj->write_domain & I915_GEM_GPU_DOMAINS);
2711 
2712 	trace_i915_gem_object_bind(obj, obj_priv->gtt_offset);
2713 
2714 	return 0;
2715 }
2716 
2717 void
2718 i915_gem_clflush_object(struct drm_gem_object *obj)
2719 {
2720 	struct drm_i915_gem_object	*obj_priv = to_intel_bo(obj);
2721 
2722 	/* If we don't have a page list set up, then we're not pinned
2723 	 * to GPU, and we can ignore the cache flush because it'll happen
2724 	 * again at bind time.
2725 	 */
2726 	if (obj_priv->pages == NULL)
2727 		return;
2728 
2729 	trace_i915_gem_object_clflush(obj);
2730 
2731 	drm_clflush_pages(obj_priv->pages, obj->size / PAGE_SIZE);
2732 }
2733 
2734 /** Flushes any GPU write domain for the object if it's dirty. */
2735 static void
2736 i915_gem_object_flush_gpu_write_domain(struct drm_gem_object *obj)
2737 {
2738 	struct drm_device *dev = obj->dev;
2739 	uint32_t old_write_domain;
2740 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2741 
2742 	if ((obj->write_domain & I915_GEM_GPU_DOMAINS) == 0)
2743 		return;
2744 
2745 	/* Queue the GPU write cache flushing we need. */
2746 	old_write_domain = obj->write_domain;
2747 	i915_gem_flush(dev, 0, obj->write_domain);
2748 	(void) i915_add_request(dev, NULL, obj->write_domain, obj_priv->ring);
2749 	BUG_ON(obj->write_domain);
2750 
2751 	trace_i915_gem_object_change_domain(obj,
2752 					    obj->read_domains,
2753 					    old_write_domain);
2754 }
2755 
2756 /** Flushes the GTT write domain for the object if it's dirty. */
2757 static void
2758 i915_gem_object_flush_gtt_write_domain(struct drm_gem_object *obj)
2759 {
2760 	uint32_t old_write_domain;
2761 
2762 	if (obj->write_domain != I915_GEM_DOMAIN_GTT)
2763 		return;
2764 
2765 	/* No actual flushing is required for the GTT write domain.   Writes
2766 	 * to it immediately go to main memory as far as we know, so there's
2767 	 * no chipset flush.  It also doesn't land in render cache.
2768 	 */
2769 	old_write_domain = obj->write_domain;
2770 	obj->write_domain = 0;
2771 
2772 	trace_i915_gem_object_change_domain(obj,
2773 					    obj->read_domains,
2774 					    old_write_domain);
2775 }
2776 
2777 /** Flushes the CPU write domain for the object if it's dirty. */
2778 static void
2779 i915_gem_object_flush_cpu_write_domain(struct drm_gem_object *obj)
2780 {
2781 	struct drm_device *dev = obj->dev;
2782 	uint32_t old_write_domain;
2783 
2784 	if (obj->write_domain != I915_GEM_DOMAIN_CPU)
2785 		return;
2786 
2787 	i915_gem_clflush_object(obj);
2788 	drm_agp_chipset_flush(dev);
2789 	old_write_domain = obj->write_domain;
2790 	obj->write_domain = 0;
2791 
2792 	trace_i915_gem_object_change_domain(obj,
2793 					    obj->read_domains,
2794 					    old_write_domain);
2795 }
2796 
2797 void
2798 i915_gem_object_flush_write_domain(struct drm_gem_object *obj)
2799 {
2800 	switch (obj->write_domain) {
2801 	case I915_GEM_DOMAIN_GTT:
2802 		i915_gem_object_flush_gtt_write_domain(obj);
2803 		break;
2804 	case I915_GEM_DOMAIN_CPU:
2805 		i915_gem_object_flush_cpu_write_domain(obj);
2806 		break;
2807 	default:
2808 		i915_gem_object_flush_gpu_write_domain(obj);
2809 		break;
2810 	}
2811 }
2812 
2813 /**
2814  * Moves a single object to the GTT read, and possibly write domain.
2815  *
2816  * This function returns when the move is complete, including waiting on
2817  * flushes to occur.
2818  */
2819 int
2820 i915_gem_object_set_to_gtt_domain(struct drm_gem_object *obj, int write)
2821 {
2822 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2823 	uint32_t old_write_domain, old_read_domains;
2824 	int ret;
2825 
2826 	/* Not valid to be called on unbound objects. */
2827 	if (obj_priv->gtt_space == NULL)
2828 		return -EINVAL;
2829 
2830 	i915_gem_object_flush_gpu_write_domain(obj);
2831 	/* Wait on any GPU rendering and flushing to occur. */
2832 	ret = i915_gem_object_wait_rendering(obj);
2833 	if (ret != 0)
2834 		return ret;
2835 
2836 	old_write_domain = obj->write_domain;
2837 	old_read_domains = obj->read_domains;
2838 
2839 	/* If we're writing through the GTT domain, then CPU and GPU caches
2840 	 * will need to be invalidated at next use.
2841 	 */
2842 	if (write)
2843 		obj->read_domains &= I915_GEM_DOMAIN_GTT;
2844 
2845 	i915_gem_object_flush_cpu_write_domain(obj);
2846 
2847 	/* It should now be out of any other write domains, and we can update
2848 	 * the domain values for our changes.
2849 	 */
2850 	BUG_ON((obj->write_domain & ~I915_GEM_DOMAIN_GTT) != 0);
2851 	obj->read_domains |= I915_GEM_DOMAIN_GTT;
2852 	if (write) {
2853 		obj->write_domain = I915_GEM_DOMAIN_GTT;
2854 		obj_priv->dirty = 1;
2855 	}
2856 
2857 	trace_i915_gem_object_change_domain(obj,
2858 					    old_read_domains,
2859 					    old_write_domain);
2860 
2861 	return 0;
2862 }
2863 
2864 /*
2865  * Prepare buffer for display plane. Use uninterruptible for possible flush
2866  * wait, as in modesetting process we're not supposed to be interrupted.
2867  */
2868 int
2869 i915_gem_object_set_to_display_plane(struct drm_gem_object *obj)
2870 {
2871 	struct drm_device *dev = obj->dev;
2872 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
2873 	uint32_t old_write_domain, old_read_domains;
2874 	int ret;
2875 
2876 	/* Not valid to be called on unbound objects. */
2877 	if (obj_priv->gtt_space == NULL)
2878 		return -EINVAL;
2879 
2880 	i915_gem_object_flush_gpu_write_domain(obj);
2881 
2882 	/* Wait on any GPU rendering and flushing to occur. */
2883 	if (obj_priv->active) {
2884 #if WATCH_BUF
2885 		DRM_INFO("%s: object %p wait for seqno %08x\n",
2886 			  __func__, obj, obj_priv->last_rendering_seqno);
2887 #endif
2888 		ret = i915_do_wait_request(dev,
2889 				obj_priv->last_rendering_seqno,
2890 				0,
2891 				obj_priv->ring);
2892 		if (ret != 0)
2893 			return ret;
2894 	}
2895 
2896 	i915_gem_object_flush_cpu_write_domain(obj);
2897 
2898 	old_write_domain = obj->write_domain;
2899 	old_read_domains = obj->read_domains;
2900 
2901 	/* It should now be out of any other write domains, and we can update
2902 	 * the domain values for our changes.
2903 	 */
2904 	BUG_ON((obj->write_domain & ~I915_GEM_DOMAIN_GTT) != 0);
2905 	obj->read_domains = I915_GEM_DOMAIN_GTT;
2906 	obj->write_domain = I915_GEM_DOMAIN_GTT;
2907 	obj_priv->dirty = 1;
2908 
2909 	trace_i915_gem_object_change_domain(obj,
2910 					    old_read_domains,
2911 					    old_write_domain);
2912 
2913 	return 0;
2914 }
2915 
2916 /**
2917  * Moves a single object to the CPU read, and possibly write domain.
2918  *
2919  * This function returns when the move is complete, including waiting on
2920  * flushes to occur.
2921  */
2922 static int
2923 i915_gem_object_set_to_cpu_domain(struct drm_gem_object *obj, int write)
2924 {
2925 	uint32_t old_write_domain, old_read_domains;
2926 	int ret;
2927 
2928 	i915_gem_object_flush_gpu_write_domain(obj);
2929 	/* Wait on any GPU rendering and flushing to occur. */
2930 	ret = i915_gem_object_wait_rendering(obj);
2931 	if (ret != 0)
2932 		return ret;
2933 
2934 	i915_gem_object_flush_gtt_write_domain(obj);
2935 
2936 	/* If we have a partially-valid cache of the object in the CPU,
2937 	 * finish invalidating it and free the per-page flags.
2938 	 */
2939 	i915_gem_object_set_to_full_cpu_read_domain(obj);
2940 
2941 	old_write_domain = obj->write_domain;
2942 	old_read_domains = obj->read_domains;
2943 
2944 	/* Flush the CPU cache if it's still invalid. */
2945 	if ((obj->read_domains & I915_GEM_DOMAIN_CPU) == 0) {
2946 		i915_gem_clflush_object(obj);
2947 
2948 		obj->read_domains |= I915_GEM_DOMAIN_CPU;
2949 	}
2950 
2951 	/* It should now be out of any other write domains, and we can update
2952 	 * the domain values for our changes.
2953 	 */
2954 	BUG_ON((obj->write_domain & ~I915_GEM_DOMAIN_CPU) != 0);
2955 
2956 	/* If we're writing through the CPU, then the GPU read domains will
2957 	 * need to be invalidated at next use.
2958 	 */
2959 	if (write) {
2960 		obj->read_domains &= I915_GEM_DOMAIN_CPU;
2961 		obj->write_domain = I915_GEM_DOMAIN_CPU;
2962 	}
2963 
2964 	trace_i915_gem_object_change_domain(obj,
2965 					    old_read_domains,
2966 					    old_write_domain);
2967 
2968 	return 0;
2969 }
2970 
2971 /*
2972  * Set the next domain for the specified object. This
2973  * may not actually perform the necessary flushing/invaliding though,
2974  * as that may want to be batched with other set_domain operations
2975  *
2976  * This is (we hope) the only really tricky part of gem. The goal
2977  * is fairly simple -- track which caches hold bits of the object
2978  * and make sure they remain coherent. A few concrete examples may
2979  * help to explain how it works. For shorthand, we use the notation
2980  * (read_domains, write_domain), e.g. (CPU, CPU) to indicate the
2981  * a pair of read and write domain masks.
2982  *
2983  * Case 1: the batch buffer
2984  *
2985  *	1. Allocated
2986  *	2. Written by CPU
2987  *	3. Mapped to GTT
2988  *	4. Read by GPU
2989  *	5. Unmapped from GTT
2990  *	6. Freed
2991  *
2992  *	Let's take these a step at a time
2993  *
2994  *	1. Allocated
2995  *		Pages allocated from the kernel may still have
2996  *		cache contents, so we set them to (CPU, CPU) always.
2997  *	2. Written by CPU (using pwrite)
2998  *		The pwrite function calls set_domain (CPU, CPU) and
2999  *		this function does nothing (as nothing changes)
3000  *	3. Mapped by GTT
3001  *		This function asserts that the object is not
3002  *		currently in any GPU-based read or write domains
3003  *	4. Read by GPU
3004  *		i915_gem_execbuffer calls set_domain (COMMAND, 0).
3005  *		As write_domain is zero, this function adds in the
3006  *		current read domains (CPU+COMMAND, 0).
3007  *		flush_domains is set to CPU.
3008  *		invalidate_domains is set to COMMAND
3009  *		clflush is run to get data out of the CPU caches
3010  *		then i915_dev_set_domain calls i915_gem_flush to
3011  *		emit an MI_FLUSH and drm_agp_chipset_flush
3012  *	5. Unmapped from GTT
3013  *		i915_gem_object_unbind calls set_domain (CPU, CPU)
3014  *		flush_domains and invalidate_domains end up both zero
3015  *		so no flushing/invalidating happens
3016  *	6. Freed
3017  *		yay, done
3018  *
3019  * Case 2: The shared render buffer
3020  *
3021  *	1. Allocated
3022  *	2. Mapped to GTT
3023  *	3. Read/written by GPU
3024  *	4. set_domain to (CPU,CPU)
3025  *	5. Read/written by CPU
3026  *	6. Read/written by GPU
3027  *
3028  *	1. Allocated
3029  *		Same as last example, (CPU, CPU)
3030  *	2. Mapped to GTT
3031  *		Nothing changes (assertions find that it is not in the GPU)
3032  *	3. Read/written by GPU
3033  *		execbuffer calls set_domain (RENDER, RENDER)
3034  *		flush_domains gets CPU
3035  *		invalidate_domains gets GPU
3036  *		clflush (obj)
3037  *		MI_FLUSH and drm_agp_chipset_flush
3038  *	4. set_domain (CPU, CPU)
3039  *		flush_domains gets GPU
3040  *		invalidate_domains gets CPU
3041  *		wait_rendering (obj) to make sure all drawing is complete.
3042  *		This will include an MI_FLUSH to get the data from GPU
3043  *		to memory
3044  *		clflush (obj) to invalidate the CPU cache
3045  *		Another MI_FLUSH in i915_gem_flush (eliminate this somehow?)
3046  *	5. Read/written by CPU
3047  *		cache lines are loaded and dirtied
3048  *	6. Read written by GPU
3049  *		Same as last GPU access
3050  *
3051  * Case 3: The constant buffer
3052  *
3053  *	1. Allocated
3054  *	2. Written by CPU
3055  *	3. Read by GPU
3056  *	4. Updated (written) by CPU again
3057  *	5. Read by GPU
3058  *
3059  *	1. Allocated
3060  *		(CPU, CPU)
3061  *	2. Written by CPU
3062  *		(CPU, CPU)
3063  *	3. Read by GPU
3064  *		(CPU+RENDER, 0)
3065  *		flush_domains = CPU
3066  *		invalidate_domains = RENDER
3067  *		clflush (obj)
3068  *		MI_FLUSH
3069  *		drm_agp_chipset_flush
3070  *	4. Updated (written) by CPU again
3071  *		(CPU, CPU)
3072  *		flush_domains = 0 (no previous write domain)
3073  *		invalidate_domains = 0 (no new read domains)
3074  *	5. Read by GPU
3075  *		(CPU+RENDER, 0)
3076  *		flush_domains = CPU
3077  *		invalidate_domains = RENDER
3078  *		clflush (obj)
3079  *		MI_FLUSH
3080  *		drm_agp_chipset_flush
3081  */
3082 static void
3083 i915_gem_object_set_to_gpu_domain(struct drm_gem_object *obj)
3084 {
3085 	struct drm_device		*dev = obj->dev;
3086 	struct drm_i915_gem_object	*obj_priv = to_intel_bo(obj);
3087 	uint32_t			invalidate_domains = 0;
3088 	uint32_t			flush_domains = 0;
3089 	uint32_t			old_read_domains;
3090 
3091 	BUG_ON(obj->pending_read_domains & I915_GEM_DOMAIN_CPU);
3092 	BUG_ON(obj->pending_write_domain == I915_GEM_DOMAIN_CPU);
3093 
3094 	intel_mark_busy(dev, obj);
3095 
3096 #if WATCH_BUF
3097 	DRM_INFO("%s: object %p read %08x -> %08x write %08x -> %08x\n",
3098 		 __func__, obj,
3099 		 obj->read_domains, obj->pending_read_domains,
3100 		 obj->write_domain, obj->pending_write_domain);
3101 #endif
3102 	/*
3103 	 * If the object isn't moving to a new write domain,
3104 	 * let the object stay in multiple read domains
3105 	 */
3106 	if (obj->pending_write_domain == 0)
3107 		obj->pending_read_domains |= obj->read_domains;
3108 	else
3109 		obj_priv->dirty = 1;
3110 
3111 	/*
3112 	 * Flush the current write domain if
3113 	 * the new read domains don't match. Invalidate
3114 	 * any read domains which differ from the old
3115 	 * write domain
3116 	 */
3117 	if (obj->write_domain &&
3118 	    obj->write_domain != obj->pending_read_domains) {
3119 		flush_domains |= obj->write_domain;
3120 		invalidate_domains |=
3121 			obj->pending_read_domains & ~obj->write_domain;
3122 	}
3123 	/*
3124 	 * Invalidate any read caches which may have
3125 	 * stale data. That is, any new read domains.
3126 	 */
3127 	invalidate_domains |= obj->pending_read_domains & ~obj->read_domains;
3128 	if ((flush_domains | invalidate_domains) & I915_GEM_DOMAIN_CPU) {
3129 #if WATCH_BUF
3130 		DRM_INFO("%s: CPU domain flush %08x invalidate %08x\n",
3131 			 __func__, flush_domains, invalidate_domains);
3132 #endif
3133 		i915_gem_clflush_object(obj);
3134 	}
3135 
3136 	old_read_domains = obj->read_domains;
3137 
3138 	/* The actual obj->write_domain will be updated with
3139 	 * pending_write_domain after we emit the accumulated flush for all
3140 	 * of our domain changes in execbuffers (which clears objects'
3141 	 * write_domains).  So if we have a current write domain that we
3142 	 * aren't changing, set pending_write_domain to that.
3143 	 */
3144 	if (flush_domains == 0 && obj->pending_write_domain == 0)
3145 		obj->pending_write_domain = obj->write_domain;
3146 	obj->read_domains = obj->pending_read_domains;
3147 
3148 	dev->invalidate_domains |= invalidate_domains;
3149 	dev->flush_domains |= flush_domains;
3150 #if WATCH_BUF
3151 	DRM_INFO("%s: read %08x write %08x invalidate %08x flush %08x\n",
3152 		 __func__,
3153 		 obj->read_domains, obj->write_domain,
3154 		 dev->invalidate_domains, dev->flush_domains);
3155 #endif
3156 
3157 	trace_i915_gem_object_change_domain(obj,
3158 					    old_read_domains,
3159 					    obj->write_domain);
3160 }
3161 
3162 /**
3163  * Moves the object from a partially CPU read to a full one.
3164  *
3165  * Note that this only resolves i915_gem_object_set_cpu_read_domain_range(),
3166  * and doesn't handle transitioning from !(read_domains & I915_GEM_DOMAIN_CPU).
3167  */
3168 static void
3169 i915_gem_object_set_to_full_cpu_read_domain(struct drm_gem_object *obj)
3170 {
3171 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
3172 
3173 	if (!obj_priv->page_cpu_valid)
3174 		return;
3175 
3176 	/* If we're partially in the CPU read domain, finish moving it in.
3177 	 */
3178 	if (obj->read_domains & I915_GEM_DOMAIN_CPU) {
3179 		int i;
3180 
3181 		for (i = 0; i <= (obj->size - 1) / PAGE_SIZE; i++) {
3182 			if (obj_priv->page_cpu_valid[i])
3183 				continue;
3184 			drm_clflush_pages(obj_priv->pages + i, 1);
3185 		}
3186 	}
3187 
3188 	/* Free the page_cpu_valid mappings which are now stale, whether
3189 	 * or not we've got I915_GEM_DOMAIN_CPU.
3190 	 */
3191 	kfree(obj_priv->page_cpu_valid);
3192 	obj_priv->page_cpu_valid = NULL;
3193 }
3194 
3195 /**
3196  * Set the CPU read domain on a range of the object.
3197  *
3198  * The object ends up with I915_GEM_DOMAIN_CPU in its read flags although it's
3199  * not entirely valid.  The page_cpu_valid member of the object flags which
3200  * pages have been flushed, and will be respected by
3201  * i915_gem_object_set_to_cpu_domain() if it's called on to get a valid mapping
3202  * of the whole object.
3203  *
3204  * This function returns when the move is complete, including waiting on
3205  * flushes to occur.
3206  */
3207 static int
3208 i915_gem_object_set_cpu_read_domain_range(struct drm_gem_object *obj,
3209 					  uint64_t offset, uint64_t size)
3210 {
3211 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
3212 	uint32_t old_read_domains;
3213 	int i, ret;
3214 
3215 	if (offset == 0 && size == obj->size)
3216 		return i915_gem_object_set_to_cpu_domain(obj, 0);
3217 
3218 	i915_gem_object_flush_gpu_write_domain(obj);
3219 	/* Wait on any GPU rendering and flushing to occur. */
3220 	ret = i915_gem_object_wait_rendering(obj);
3221 	if (ret != 0)
3222 		return ret;
3223 	i915_gem_object_flush_gtt_write_domain(obj);
3224 
3225 	/* If we're already fully in the CPU read domain, we're done. */
3226 	if (obj_priv->page_cpu_valid == NULL &&
3227 	    (obj->read_domains & I915_GEM_DOMAIN_CPU) != 0)
3228 		return 0;
3229 
3230 	/* Otherwise, create/clear the per-page CPU read domain flag if we're
3231 	 * newly adding I915_GEM_DOMAIN_CPU
3232 	 */
3233 	if (obj_priv->page_cpu_valid == NULL) {
3234 		obj_priv->page_cpu_valid = kzalloc(obj->size / PAGE_SIZE,
3235 						   GFP_KERNEL);
3236 		if (obj_priv->page_cpu_valid == NULL)
3237 			return -ENOMEM;
3238 	} else if ((obj->read_domains & I915_GEM_DOMAIN_CPU) == 0)
3239 		memset(obj_priv->page_cpu_valid, 0, obj->size / PAGE_SIZE);
3240 
3241 	/* Flush the cache on any pages that are still invalid from the CPU's
3242 	 * perspective.
3243 	 */
3244 	for (i = offset / PAGE_SIZE; i <= (offset + size - 1) / PAGE_SIZE;
3245 	     i++) {
3246 		if (obj_priv->page_cpu_valid[i])
3247 			continue;
3248 
3249 		drm_clflush_pages(obj_priv->pages + i, 1);
3250 
3251 		obj_priv->page_cpu_valid[i] = 1;
3252 	}
3253 
3254 	/* It should now be out of any other write domains, and we can update
3255 	 * the domain values for our changes.
3256 	 */
3257 	BUG_ON((obj->write_domain & ~I915_GEM_DOMAIN_CPU) != 0);
3258 
3259 	old_read_domains = obj->read_domains;
3260 	obj->read_domains |= I915_GEM_DOMAIN_CPU;
3261 
3262 	trace_i915_gem_object_change_domain(obj,
3263 					    old_read_domains,
3264 					    obj->write_domain);
3265 
3266 	return 0;
3267 }
3268 
3269 /**
3270  * Pin an object to the GTT and evaluate the relocations landing in it.
3271  */
3272 static int
3273 i915_gem_object_pin_and_relocate(struct drm_gem_object *obj,
3274 				 struct drm_file *file_priv,
3275 				 struct drm_i915_gem_exec_object2 *entry,
3276 				 struct drm_i915_gem_relocation_entry *relocs)
3277 {
3278 	struct drm_device *dev = obj->dev;
3279 	drm_i915_private_t *dev_priv = dev->dev_private;
3280 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
3281 	int i, ret;
3282 	void __iomem *reloc_page;
3283 	bool need_fence;
3284 
3285 	need_fence = entry->flags & EXEC_OBJECT_NEEDS_FENCE &&
3286 	             obj_priv->tiling_mode != I915_TILING_NONE;
3287 
3288 	/* Check fence reg constraints and rebind if necessary */
3289 	if (need_fence &&
3290 	    !i915_gem_object_fence_offset_ok(obj,
3291 					     obj_priv->tiling_mode)) {
3292 		ret = i915_gem_object_unbind(obj);
3293 		if (ret)
3294 			return ret;
3295 	}
3296 
3297 	/* Choose the GTT offset for our buffer and put it there. */
3298 	ret = i915_gem_object_pin(obj, (uint32_t) entry->alignment);
3299 	if (ret)
3300 		return ret;
3301 
3302 	/*
3303 	 * Pre-965 chips need a fence register set up in order to
3304 	 * properly handle blits to/from tiled surfaces.
3305 	 */
3306 	if (need_fence) {
3307 		ret = i915_gem_object_get_fence_reg(obj);
3308 		if (ret != 0) {
3309 			i915_gem_object_unpin(obj);
3310 			return ret;
3311 		}
3312 	}
3313 
3314 	entry->offset = obj_priv->gtt_offset;
3315 
3316 	/* Apply the relocations, using the GTT aperture to avoid cache
3317 	 * flushing requirements.
3318 	 */
3319 	for (i = 0; i < entry->relocation_count; i++) {
3320 		struct drm_i915_gem_relocation_entry *reloc= &relocs[i];
3321 		struct drm_gem_object *target_obj;
3322 		struct drm_i915_gem_object *target_obj_priv;
3323 		uint32_t reloc_val, reloc_offset;
3324 		uint32_t __iomem *reloc_entry;
3325 
3326 		target_obj = drm_gem_object_lookup(obj->dev, file_priv,
3327 						   reloc->target_handle);
3328 		if (target_obj == NULL) {
3329 			i915_gem_object_unpin(obj);
3330 			return -EBADF;
3331 		}
3332 		target_obj_priv = to_intel_bo(target_obj);
3333 
3334 #if WATCH_RELOC
3335 		DRM_INFO("%s: obj %p offset %08x target %d "
3336 			 "read %08x write %08x gtt %08x "
3337 			 "presumed %08x delta %08x\n",
3338 			 __func__,
3339 			 obj,
3340 			 (int) reloc->offset,
3341 			 (int) reloc->target_handle,
3342 			 (int) reloc->read_domains,
3343 			 (int) reloc->write_domain,
3344 			 (int) target_obj_priv->gtt_offset,
3345 			 (int) reloc->presumed_offset,
3346 			 reloc->delta);
3347 #endif
3348 
3349 		/* The target buffer should have appeared before us in the
3350 		 * exec_object list, so it should have a GTT space bound by now.
3351 		 */
3352 		if (target_obj_priv->gtt_space == NULL) {
3353 			DRM_ERROR("No GTT space found for object %d\n",
3354 				  reloc->target_handle);
3355 			drm_gem_object_unreference(target_obj);
3356 			i915_gem_object_unpin(obj);
3357 			return -EINVAL;
3358 		}
3359 
3360 		/* Validate that the target is in a valid r/w GPU domain */
3361 		if (reloc->write_domain & (reloc->write_domain - 1)) {
3362 			DRM_ERROR("reloc with multiple write domains: "
3363 				  "obj %p target %d offset %d "
3364 				  "read %08x write %08x",
3365 				  obj, reloc->target_handle,
3366 				  (int) reloc->offset,
3367 				  reloc->read_domains,
3368 				  reloc->write_domain);
3369 			return -EINVAL;
3370 		}
3371 		if (reloc->write_domain & I915_GEM_DOMAIN_CPU ||
3372 		    reloc->read_domains & I915_GEM_DOMAIN_CPU) {
3373 			DRM_ERROR("reloc with read/write CPU domains: "
3374 				  "obj %p target %d offset %d "
3375 				  "read %08x write %08x",
3376 				  obj, reloc->target_handle,
3377 				  (int) reloc->offset,
3378 				  reloc->read_domains,
3379 				  reloc->write_domain);
3380 			drm_gem_object_unreference(target_obj);
3381 			i915_gem_object_unpin(obj);
3382 			return -EINVAL;
3383 		}
3384 		if (reloc->write_domain && target_obj->pending_write_domain &&
3385 		    reloc->write_domain != target_obj->pending_write_domain) {
3386 			DRM_ERROR("Write domain conflict: "
3387 				  "obj %p target %d offset %d "
3388 				  "new %08x old %08x\n",
3389 				  obj, reloc->target_handle,
3390 				  (int) reloc->offset,
3391 				  reloc->write_domain,
3392 				  target_obj->pending_write_domain);
3393 			drm_gem_object_unreference(target_obj);
3394 			i915_gem_object_unpin(obj);
3395 			return -EINVAL;
3396 		}
3397 
3398 		target_obj->pending_read_domains |= reloc->read_domains;
3399 		target_obj->pending_write_domain |= reloc->write_domain;
3400 
3401 		/* If the relocation already has the right value in it, no
3402 		 * more work needs to be done.
3403 		 */
3404 		if (target_obj_priv->gtt_offset == reloc->presumed_offset) {
3405 			drm_gem_object_unreference(target_obj);
3406 			continue;
3407 		}
3408 
3409 		/* Check that the relocation address is valid... */
3410 		if (reloc->offset > obj->size - 4) {
3411 			DRM_ERROR("Relocation beyond object bounds: "
3412 				  "obj %p target %d offset %d size %d.\n",
3413 				  obj, reloc->target_handle,
3414 				  (int) reloc->offset, (int) obj->size);
3415 			drm_gem_object_unreference(target_obj);
3416 			i915_gem_object_unpin(obj);
3417 			return -EINVAL;
3418 		}
3419 		if (reloc->offset & 3) {
3420 			DRM_ERROR("Relocation not 4-byte aligned: "
3421 				  "obj %p target %d offset %d.\n",
3422 				  obj, reloc->target_handle,
3423 				  (int) reloc->offset);
3424 			drm_gem_object_unreference(target_obj);
3425 			i915_gem_object_unpin(obj);
3426 			return -EINVAL;
3427 		}
3428 
3429 		/* and points to somewhere within the target object. */
3430 		if (reloc->delta >= target_obj->size) {
3431 			DRM_ERROR("Relocation beyond target object bounds: "
3432 				  "obj %p target %d delta %d size %d.\n",
3433 				  obj, reloc->target_handle,
3434 				  (int) reloc->delta, (int) target_obj->size);
3435 			drm_gem_object_unreference(target_obj);
3436 			i915_gem_object_unpin(obj);
3437 			return -EINVAL;
3438 		}
3439 
3440 		ret = i915_gem_object_set_to_gtt_domain(obj, 1);
3441 		if (ret != 0) {
3442 			drm_gem_object_unreference(target_obj);
3443 			i915_gem_object_unpin(obj);
3444 			return -EINVAL;
3445 		}
3446 
3447 		/* Map the page containing the relocation we're going to
3448 		 * perform.
3449 		 */
3450 		reloc_offset = obj_priv->gtt_offset + reloc->offset;
3451 		reloc_page = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping,
3452 						      (reloc_offset &
3453 						       ~(PAGE_SIZE - 1)));
3454 		reloc_entry = (uint32_t __iomem *)(reloc_page +
3455 						   (reloc_offset & (PAGE_SIZE - 1)));
3456 		reloc_val = target_obj_priv->gtt_offset + reloc->delta;
3457 
3458 #if WATCH_BUF
3459 		DRM_INFO("Applied relocation: %p@0x%08x %08x -> %08x\n",
3460 			  obj, (unsigned int) reloc->offset,
3461 			  readl(reloc_entry), reloc_val);
3462 #endif
3463 		writel(reloc_val, reloc_entry);
3464 		io_mapping_unmap_atomic(reloc_page);
3465 
3466 		/* The updated presumed offset for this entry will be
3467 		 * copied back out to the user.
3468 		 */
3469 		reloc->presumed_offset = target_obj_priv->gtt_offset;
3470 
3471 		drm_gem_object_unreference(target_obj);
3472 	}
3473 
3474 #if WATCH_BUF
3475 	if (0)
3476 		i915_gem_dump_object(obj, 128, __func__, ~0);
3477 #endif
3478 	return 0;
3479 }
3480 
3481 /* Throttle our rendering by waiting until the ring has completed our requests
3482  * emitted over 20 msec ago.
3483  *
3484  * Note that if we were to use the current jiffies each time around the loop,
3485  * we wouldn't escape the function with any frames outstanding if the time to
3486  * render a frame was over 20ms.
3487  *
3488  * This should get us reasonable parallelism between CPU and GPU but also
3489  * relatively low latency when blocking on a particular request to finish.
3490  */
3491 static int
3492 i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file_priv)
3493 {
3494 	struct drm_i915_file_private *i915_file_priv = file_priv->driver_priv;
3495 	int ret = 0;
3496 	unsigned long recent_enough = jiffies - msecs_to_jiffies(20);
3497 
3498 	mutex_lock(&dev->struct_mutex);
3499 	while (!list_empty(&i915_file_priv->mm.request_list)) {
3500 		struct drm_i915_gem_request *request;
3501 
3502 		request = list_first_entry(&i915_file_priv->mm.request_list,
3503 					   struct drm_i915_gem_request,
3504 					   client_list);
3505 
3506 		if (time_after_eq(request->emitted_jiffies, recent_enough))
3507 			break;
3508 
3509 		ret = i915_wait_request(dev, request->seqno, request->ring);
3510 		if (ret != 0)
3511 			break;
3512 	}
3513 	mutex_unlock(&dev->struct_mutex);
3514 
3515 	return ret;
3516 }
3517 
3518 static int
3519 i915_gem_get_relocs_from_user(struct drm_i915_gem_exec_object2 *exec_list,
3520 			      uint32_t buffer_count,
3521 			      struct drm_i915_gem_relocation_entry **relocs)
3522 {
3523 	uint32_t reloc_count = 0, reloc_index = 0, i;
3524 	int ret;
3525 
3526 	*relocs = NULL;
3527 	for (i = 0; i < buffer_count; i++) {
3528 		if (reloc_count + exec_list[i].relocation_count < reloc_count)
3529 			return -EINVAL;
3530 		reloc_count += exec_list[i].relocation_count;
3531 	}
3532 
3533 	*relocs = drm_calloc_large(reloc_count, sizeof(**relocs));
3534 	if (*relocs == NULL) {
3535 		DRM_ERROR("failed to alloc relocs, count %d\n", reloc_count);
3536 		return -ENOMEM;
3537 	}
3538 
3539 	for (i = 0; i < buffer_count; i++) {
3540 		struct drm_i915_gem_relocation_entry __user *user_relocs;
3541 
3542 		user_relocs = (void __user *)(uintptr_t)exec_list[i].relocs_ptr;
3543 
3544 		ret = copy_from_user(&(*relocs)[reloc_index],
3545 				     user_relocs,
3546 				     exec_list[i].relocation_count *
3547 				     sizeof(**relocs));
3548 		if (ret != 0) {
3549 			drm_free_large(*relocs);
3550 			*relocs = NULL;
3551 			return -EFAULT;
3552 		}
3553 
3554 		reloc_index += exec_list[i].relocation_count;
3555 	}
3556 
3557 	return 0;
3558 }
3559 
3560 static int
3561 i915_gem_put_relocs_to_user(struct drm_i915_gem_exec_object2 *exec_list,
3562 			    uint32_t buffer_count,
3563 			    struct drm_i915_gem_relocation_entry *relocs)
3564 {
3565 	uint32_t reloc_count = 0, i;
3566 	int ret = 0;
3567 
3568 	if (relocs == NULL)
3569 	    return 0;
3570 
3571 	for (i = 0; i < buffer_count; i++) {
3572 		struct drm_i915_gem_relocation_entry __user *user_relocs;
3573 		int unwritten;
3574 
3575 		user_relocs = (void __user *)(uintptr_t)exec_list[i].relocs_ptr;
3576 
3577 		unwritten = copy_to_user(user_relocs,
3578 					 &relocs[reloc_count],
3579 					 exec_list[i].relocation_count *
3580 					 sizeof(*relocs));
3581 
3582 		if (unwritten) {
3583 			ret = -EFAULT;
3584 			goto err;
3585 		}
3586 
3587 		reloc_count += exec_list[i].relocation_count;
3588 	}
3589 
3590 err:
3591 	drm_free_large(relocs);
3592 
3593 	return ret;
3594 }
3595 
3596 static int
3597 i915_gem_check_execbuffer (struct drm_i915_gem_execbuffer2 *exec,
3598 			   uint64_t exec_offset)
3599 {
3600 	uint32_t exec_start, exec_len;
3601 
3602 	exec_start = (uint32_t) exec_offset + exec->batch_start_offset;
3603 	exec_len = (uint32_t) exec->batch_len;
3604 
3605 	if ((exec_start | exec_len) & 0x7)
3606 		return -EINVAL;
3607 
3608 	if (!exec_start)
3609 		return -EINVAL;
3610 
3611 	return 0;
3612 }
3613 
3614 static int
3615 i915_gem_wait_for_pending_flip(struct drm_device *dev,
3616 			       struct drm_gem_object **object_list,
3617 			       int count)
3618 {
3619 	drm_i915_private_t *dev_priv = dev->dev_private;
3620 	struct drm_i915_gem_object *obj_priv;
3621 	DEFINE_WAIT(wait);
3622 	int i, ret = 0;
3623 
3624 	for (;;) {
3625 		prepare_to_wait(&dev_priv->pending_flip_queue,
3626 				&wait, TASK_INTERRUPTIBLE);
3627 		for (i = 0; i < count; i++) {
3628 			obj_priv = to_intel_bo(object_list[i]);
3629 			if (atomic_read(&obj_priv->pending_flip) > 0)
3630 				break;
3631 		}
3632 		if (i == count)
3633 			break;
3634 
3635 		if (!signal_pending(current)) {
3636 			mutex_unlock(&dev->struct_mutex);
3637 			schedule();
3638 			mutex_lock(&dev->struct_mutex);
3639 			continue;
3640 		}
3641 		ret = -ERESTARTSYS;
3642 		break;
3643 	}
3644 	finish_wait(&dev_priv->pending_flip_queue, &wait);
3645 
3646 	return ret;
3647 }
3648 
3649 int
3650 i915_gem_do_execbuffer(struct drm_device *dev, void *data,
3651 		       struct drm_file *file_priv,
3652 		       struct drm_i915_gem_execbuffer2 *args,
3653 		       struct drm_i915_gem_exec_object2 *exec_list)
3654 {
3655 	drm_i915_private_t *dev_priv = dev->dev_private;
3656 	struct drm_gem_object **object_list = NULL;
3657 	struct drm_gem_object *batch_obj;
3658 	struct drm_i915_gem_object *obj_priv;
3659 	struct drm_clip_rect *cliprects = NULL;
3660 	struct drm_i915_gem_relocation_entry *relocs = NULL;
3661 	int ret = 0, ret2, i, pinned = 0;
3662 	uint64_t exec_offset;
3663 	uint32_t seqno, flush_domains, reloc_index;
3664 	int pin_tries, flips;
3665 
3666 	struct intel_ring_buffer *ring = NULL;
3667 
3668 #if WATCH_EXEC
3669 	DRM_INFO("buffers_ptr %d buffer_count %d len %08x\n",
3670 		  (int) args->buffers_ptr, args->buffer_count, args->batch_len);
3671 #endif
3672 	if (args->flags & I915_EXEC_BSD) {
3673 		if (!HAS_BSD(dev)) {
3674 			DRM_ERROR("execbuf with wrong flag\n");
3675 			return -EINVAL;
3676 		}
3677 		ring = &dev_priv->bsd_ring;
3678 	} else {
3679 		ring = &dev_priv->render_ring;
3680 	}
3681 
3682 
3683 	if (args->buffer_count < 1) {
3684 		DRM_ERROR("execbuf with %d buffers\n", args->buffer_count);
3685 		return -EINVAL;
3686 	}
3687 	object_list = drm_malloc_ab(sizeof(*object_list), args->buffer_count);
3688 	if (object_list == NULL) {
3689 		DRM_ERROR("Failed to allocate object list for %d buffers\n",
3690 			  args->buffer_count);
3691 		ret = -ENOMEM;
3692 		goto pre_mutex_err;
3693 	}
3694 
3695 	if (args->num_cliprects != 0) {
3696 		cliprects = kcalloc(args->num_cliprects, sizeof(*cliprects),
3697 				    GFP_KERNEL);
3698 		if (cliprects == NULL) {
3699 			ret = -ENOMEM;
3700 			goto pre_mutex_err;
3701 		}
3702 
3703 		ret = copy_from_user(cliprects,
3704 				     (struct drm_clip_rect __user *)
3705 				     (uintptr_t) args->cliprects_ptr,
3706 				     sizeof(*cliprects) * args->num_cliprects);
3707 		if (ret != 0) {
3708 			DRM_ERROR("copy %d cliprects failed: %d\n",
3709 				  args->num_cliprects, ret);
3710 			goto pre_mutex_err;
3711 		}
3712 	}
3713 
3714 	ret = i915_gem_get_relocs_from_user(exec_list, args->buffer_count,
3715 					    &relocs);
3716 	if (ret != 0)
3717 		goto pre_mutex_err;
3718 
3719 	mutex_lock(&dev->struct_mutex);
3720 
3721 	i915_verify_inactive(dev, __FILE__, __LINE__);
3722 
3723 	if (atomic_read(&dev_priv->mm.wedged)) {
3724 		mutex_unlock(&dev->struct_mutex);
3725 		ret = -EIO;
3726 		goto pre_mutex_err;
3727 	}
3728 
3729 	if (dev_priv->mm.suspended) {
3730 		mutex_unlock(&dev->struct_mutex);
3731 		ret = -EBUSY;
3732 		goto pre_mutex_err;
3733 	}
3734 
3735 	/* Look up object handles */
3736 	flips = 0;
3737 	for (i = 0; i < args->buffer_count; i++) {
3738 		object_list[i] = drm_gem_object_lookup(dev, file_priv,
3739 						       exec_list[i].handle);
3740 		if (object_list[i] == NULL) {
3741 			DRM_ERROR("Invalid object handle %d at index %d\n",
3742 				   exec_list[i].handle, i);
3743 			/* prevent error path from reading uninitialized data */
3744 			args->buffer_count = i + 1;
3745 			ret = -EBADF;
3746 			goto err;
3747 		}
3748 
3749 		obj_priv = to_intel_bo(object_list[i]);
3750 		if (obj_priv->in_execbuffer) {
3751 			DRM_ERROR("Object %p appears more than once in object list\n",
3752 				   object_list[i]);
3753 			/* prevent error path from reading uninitialized data */
3754 			args->buffer_count = i + 1;
3755 			ret = -EBADF;
3756 			goto err;
3757 		}
3758 		obj_priv->in_execbuffer = true;
3759 		flips += atomic_read(&obj_priv->pending_flip);
3760 	}
3761 
3762 	if (flips > 0) {
3763 		ret = i915_gem_wait_for_pending_flip(dev, object_list,
3764 						     args->buffer_count);
3765 		if (ret)
3766 			goto err;
3767 	}
3768 
3769 	/* Pin and relocate */
3770 	for (pin_tries = 0; ; pin_tries++) {
3771 		ret = 0;
3772 		reloc_index = 0;
3773 
3774 		for (i = 0; i < args->buffer_count; i++) {
3775 			object_list[i]->pending_read_domains = 0;
3776 			object_list[i]->pending_write_domain = 0;
3777 			ret = i915_gem_object_pin_and_relocate(object_list[i],
3778 							       file_priv,
3779 							       &exec_list[i],
3780 							       &relocs[reloc_index]);
3781 			if (ret)
3782 				break;
3783 			pinned = i + 1;
3784 			reloc_index += exec_list[i].relocation_count;
3785 		}
3786 		/* success */
3787 		if (ret == 0)
3788 			break;
3789 
3790 		/* error other than GTT full, or we've already tried again */
3791 		if (ret != -ENOSPC || pin_tries >= 1) {
3792 			if (ret != -ERESTARTSYS) {
3793 				unsigned long long total_size = 0;
3794 				int num_fences = 0;
3795 				for (i = 0; i < args->buffer_count; i++) {
3796 					obj_priv = object_list[i]->driver_private;
3797 
3798 					total_size += object_list[i]->size;
3799 					num_fences +=
3800 						exec_list[i].flags & EXEC_OBJECT_NEEDS_FENCE &&
3801 						obj_priv->tiling_mode != I915_TILING_NONE;
3802 				}
3803 				DRM_ERROR("Failed to pin buffer %d of %d, total %llu bytes, %d fences: %d\n",
3804 					  pinned+1, args->buffer_count,
3805 					  total_size, num_fences,
3806 					  ret);
3807 				DRM_ERROR("%d objects [%d pinned], "
3808 					  "%d object bytes [%d pinned], "
3809 					  "%d/%d gtt bytes\n",
3810 					  atomic_read(&dev->object_count),
3811 					  atomic_read(&dev->pin_count),
3812 					  atomic_read(&dev->object_memory),
3813 					  atomic_read(&dev->pin_memory),
3814 					  atomic_read(&dev->gtt_memory),
3815 					  dev->gtt_total);
3816 			}
3817 			goto err;
3818 		}
3819 
3820 		/* unpin all of our buffers */
3821 		for (i = 0; i < pinned; i++)
3822 			i915_gem_object_unpin(object_list[i]);
3823 		pinned = 0;
3824 
3825 		/* evict everyone we can from the aperture */
3826 		ret = i915_gem_evict_everything(dev);
3827 		if (ret && ret != -ENOSPC)
3828 			goto err;
3829 	}
3830 
3831 	/* Set the pending read domains for the batch buffer to COMMAND */
3832 	batch_obj = object_list[args->buffer_count-1];
3833 	if (batch_obj->pending_write_domain) {
3834 		DRM_ERROR("Attempting to use self-modifying batch buffer\n");
3835 		ret = -EINVAL;
3836 		goto err;
3837 	}
3838 	batch_obj->pending_read_domains |= I915_GEM_DOMAIN_COMMAND;
3839 
3840 	/* Sanity check the batch buffer, prior to moving objects */
3841 	exec_offset = exec_list[args->buffer_count - 1].offset;
3842 	ret = i915_gem_check_execbuffer (args, exec_offset);
3843 	if (ret != 0) {
3844 		DRM_ERROR("execbuf with invalid offset/length\n");
3845 		goto err;
3846 	}
3847 
3848 	i915_verify_inactive(dev, __FILE__, __LINE__);
3849 
3850 	/* Zero the global flush/invalidate flags. These
3851 	 * will be modified as new domains are computed
3852 	 * for each object
3853 	 */
3854 	dev->invalidate_domains = 0;
3855 	dev->flush_domains = 0;
3856 
3857 	for (i = 0; i < args->buffer_count; i++) {
3858 		struct drm_gem_object *obj = object_list[i];
3859 
3860 		/* Compute new gpu domains and update invalidate/flush */
3861 		i915_gem_object_set_to_gpu_domain(obj);
3862 	}
3863 
3864 	i915_verify_inactive(dev, __FILE__, __LINE__);
3865 
3866 	if (dev->invalidate_domains | dev->flush_domains) {
3867 #if WATCH_EXEC
3868 		DRM_INFO("%s: invalidate_domains %08x flush_domains %08x\n",
3869 			  __func__,
3870 			 dev->invalidate_domains,
3871 			 dev->flush_domains);
3872 #endif
3873 		i915_gem_flush(dev,
3874 			       dev->invalidate_domains,
3875 			       dev->flush_domains);
3876 		if (dev->flush_domains & I915_GEM_GPU_DOMAINS) {
3877 			(void)i915_add_request(dev, file_priv,
3878 					dev->flush_domains,
3879 					&dev_priv->render_ring);
3880 
3881 			if (HAS_BSD(dev))
3882 				(void)i915_add_request(dev, file_priv,
3883 						dev->flush_domains,
3884 						&dev_priv->bsd_ring);
3885 		}
3886 	}
3887 
3888 	for (i = 0; i < args->buffer_count; i++) {
3889 		struct drm_gem_object *obj = object_list[i];
3890 		struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
3891 		uint32_t old_write_domain = obj->write_domain;
3892 
3893 		obj->write_domain = obj->pending_write_domain;
3894 		if (obj->write_domain)
3895 			list_move_tail(&obj_priv->gpu_write_list,
3896 				       &dev_priv->mm.gpu_write_list);
3897 		else
3898 			list_del_init(&obj_priv->gpu_write_list);
3899 
3900 		trace_i915_gem_object_change_domain(obj,
3901 						    obj->read_domains,
3902 						    old_write_domain);
3903 	}
3904 
3905 	i915_verify_inactive(dev, __FILE__, __LINE__);
3906 
3907 #if WATCH_COHERENCY
3908 	for (i = 0; i < args->buffer_count; i++) {
3909 		i915_gem_object_check_coherency(object_list[i],
3910 						exec_list[i].handle);
3911 	}
3912 #endif
3913 
3914 #if WATCH_EXEC
3915 	i915_gem_dump_object(batch_obj,
3916 			      args->batch_len,
3917 			      __func__,
3918 			      ~0);
3919 #endif
3920 
3921 	/* Exec the batchbuffer */
3922 	ret = ring->dispatch_gem_execbuffer(dev, ring, args,
3923 			cliprects, exec_offset);
3924 	if (ret) {
3925 		DRM_ERROR("dispatch failed %d\n", ret);
3926 		goto err;
3927 	}
3928 
3929 	/*
3930 	 * Ensure that the commands in the batch buffer are
3931 	 * finished before the interrupt fires
3932 	 */
3933 	flush_domains = i915_retire_commands(dev, ring);
3934 
3935 	i915_verify_inactive(dev, __FILE__, __LINE__);
3936 
3937 	/*
3938 	 * Get a seqno representing the execution of the current buffer,
3939 	 * which we can wait on.  We would like to mitigate these interrupts,
3940 	 * likely by only creating seqnos occasionally (so that we have
3941 	 * *some* interrupts representing completion of buffers that we can
3942 	 * wait on when trying to clear up gtt space).
3943 	 */
3944 	seqno = i915_add_request(dev, file_priv, flush_domains, ring);
3945 	BUG_ON(seqno == 0);
3946 	for (i = 0; i < args->buffer_count; i++) {
3947 		struct drm_gem_object *obj = object_list[i];
3948 		obj_priv = to_intel_bo(obj);
3949 
3950 		i915_gem_object_move_to_active(obj, seqno, ring);
3951 #if WATCH_LRU
3952 		DRM_INFO("%s: move to exec list %p\n", __func__, obj);
3953 #endif
3954 	}
3955 #if WATCH_LRU
3956 	i915_dump_lru(dev, __func__);
3957 #endif
3958 
3959 	i915_verify_inactive(dev, __FILE__, __LINE__);
3960 
3961 err:
3962 	for (i = 0; i < pinned; i++)
3963 		i915_gem_object_unpin(object_list[i]);
3964 
3965 	for (i = 0; i < args->buffer_count; i++) {
3966 		if (object_list[i]) {
3967 			obj_priv = to_intel_bo(object_list[i]);
3968 			obj_priv->in_execbuffer = false;
3969 		}
3970 		drm_gem_object_unreference(object_list[i]);
3971 	}
3972 
3973 	mutex_unlock(&dev->struct_mutex);
3974 
3975 pre_mutex_err:
3976 	/* Copy the updated relocations out regardless of current error
3977 	 * state.  Failure to update the relocs would mean that the next
3978 	 * time userland calls execbuf, it would do so with presumed offset
3979 	 * state that didn't match the actual object state.
3980 	 */
3981 	ret2 = i915_gem_put_relocs_to_user(exec_list, args->buffer_count,
3982 					   relocs);
3983 	if (ret2 != 0) {
3984 		DRM_ERROR("Failed to copy relocations back out: %d\n", ret2);
3985 
3986 		if (ret == 0)
3987 			ret = ret2;
3988 	}
3989 
3990 	drm_free_large(object_list);
3991 	kfree(cliprects);
3992 
3993 	return ret;
3994 }
3995 
3996 /*
3997  * Legacy execbuffer just creates an exec2 list from the original exec object
3998  * list array and passes it to the real function.
3999  */
4000 int
4001 i915_gem_execbuffer(struct drm_device *dev, void *data,
4002 		    struct drm_file *file_priv)
4003 {
4004 	struct drm_i915_gem_execbuffer *args = data;
4005 	struct drm_i915_gem_execbuffer2 exec2;
4006 	struct drm_i915_gem_exec_object *exec_list = NULL;
4007 	struct drm_i915_gem_exec_object2 *exec2_list = NULL;
4008 	int ret, i;
4009 
4010 #if WATCH_EXEC
4011 	DRM_INFO("buffers_ptr %d buffer_count %d len %08x\n",
4012 		  (int) args->buffers_ptr, args->buffer_count, args->batch_len);
4013 #endif
4014 
4015 	if (args->buffer_count < 1) {
4016 		DRM_ERROR("execbuf with %d buffers\n", args->buffer_count);
4017 		return -EINVAL;
4018 	}
4019 
4020 	/* Copy in the exec list from userland */
4021 	exec_list = drm_malloc_ab(sizeof(*exec_list), args->buffer_count);
4022 	exec2_list = drm_malloc_ab(sizeof(*exec2_list), args->buffer_count);
4023 	if (exec_list == NULL || exec2_list == NULL) {
4024 		DRM_ERROR("Failed to allocate exec list for %d buffers\n",
4025 			  args->buffer_count);
4026 		drm_free_large(exec_list);
4027 		drm_free_large(exec2_list);
4028 		return -ENOMEM;
4029 	}
4030 	ret = copy_from_user(exec_list,
4031 			     (struct drm_i915_relocation_entry __user *)
4032 			     (uintptr_t) args->buffers_ptr,
4033 			     sizeof(*exec_list) * args->buffer_count);
4034 	if (ret != 0) {
4035 		DRM_ERROR("copy %d exec entries failed %d\n",
4036 			  args->buffer_count, ret);
4037 		drm_free_large(exec_list);
4038 		drm_free_large(exec2_list);
4039 		return -EFAULT;
4040 	}
4041 
4042 	for (i = 0; i < args->buffer_count; i++) {
4043 		exec2_list[i].handle = exec_list[i].handle;
4044 		exec2_list[i].relocation_count = exec_list[i].relocation_count;
4045 		exec2_list[i].relocs_ptr = exec_list[i].relocs_ptr;
4046 		exec2_list[i].alignment = exec_list[i].alignment;
4047 		exec2_list[i].offset = exec_list[i].offset;
4048 		if (!IS_I965G(dev))
4049 			exec2_list[i].flags = EXEC_OBJECT_NEEDS_FENCE;
4050 		else
4051 			exec2_list[i].flags = 0;
4052 	}
4053 
4054 	exec2.buffers_ptr = args->buffers_ptr;
4055 	exec2.buffer_count = args->buffer_count;
4056 	exec2.batch_start_offset = args->batch_start_offset;
4057 	exec2.batch_len = args->batch_len;
4058 	exec2.DR1 = args->DR1;
4059 	exec2.DR4 = args->DR4;
4060 	exec2.num_cliprects = args->num_cliprects;
4061 	exec2.cliprects_ptr = args->cliprects_ptr;
4062 	exec2.flags = I915_EXEC_RENDER;
4063 
4064 	ret = i915_gem_do_execbuffer(dev, data, file_priv, &exec2, exec2_list);
4065 	if (!ret) {
4066 		/* Copy the new buffer offsets back to the user's exec list. */
4067 		for (i = 0; i < args->buffer_count; i++)
4068 			exec_list[i].offset = exec2_list[i].offset;
4069 		/* ... and back out to userspace */
4070 		ret = copy_to_user((struct drm_i915_relocation_entry __user *)
4071 				   (uintptr_t) args->buffers_ptr,
4072 				   exec_list,
4073 				   sizeof(*exec_list) * args->buffer_count);
4074 		if (ret) {
4075 			ret = -EFAULT;
4076 			DRM_ERROR("failed to copy %d exec entries "
4077 				  "back to user (%d)\n",
4078 				  args->buffer_count, ret);
4079 		}
4080 	}
4081 
4082 	drm_free_large(exec_list);
4083 	drm_free_large(exec2_list);
4084 	return ret;
4085 }
4086 
4087 int
4088 i915_gem_execbuffer2(struct drm_device *dev, void *data,
4089 		     struct drm_file *file_priv)
4090 {
4091 	struct drm_i915_gem_execbuffer2 *args = data;
4092 	struct drm_i915_gem_exec_object2 *exec2_list = NULL;
4093 	int ret;
4094 
4095 #if WATCH_EXEC
4096 	DRM_INFO("buffers_ptr %d buffer_count %d len %08x\n",
4097 		  (int) args->buffers_ptr, args->buffer_count, args->batch_len);
4098 #endif
4099 
4100 	if (args->buffer_count < 1) {
4101 		DRM_ERROR("execbuf2 with %d buffers\n", args->buffer_count);
4102 		return -EINVAL;
4103 	}
4104 
4105 	exec2_list = drm_malloc_ab(sizeof(*exec2_list), args->buffer_count);
4106 	if (exec2_list == NULL) {
4107 		DRM_ERROR("Failed to allocate exec list for %d buffers\n",
4108 			  args->buffer_count);
4109 		return -ENOMEM;
4110 	}
4111 	ret = copy_from_user(exec2_list,
4112 			     (struct drm_i915_relocation_entry __user *)
4113 			     (uintptr_t) args->buffers_ptr,
4114 			     sizeof(*exec2_list) * args->buffer_count);
4115 	if (ret != 0) {
4116 		DRM_ERROR("copy %d exec entries failed %d\n",
4117 			  args->buffer_count, ret);
4118 		drm_free_large(exec2_list);
4119 		return -EFAULT;
4120 	}
4121 
4122 	ret = i915_gem_do_execbuffer(dev, data, file_priv, args, exec2_list);
4123 	if (!ret) {
4124 		/* Copy the new buffer offsets back to the user's exec list. */
4125 		ret = copy_to_user((struct drm_i915_relocation_entry __user *)
4126 				   (uintptr_t) args->buffers_ptr,
4127 				   exec2_list,
4128 				   sizeof(*exec2_list) * args->buffer_count);
4129 		if (ret) {
4130 			ret = -EFAULT;
4131 			DRM_ERROR("failed to copy %d exec entries "
4132 				  "back to user (%d)\n",
4133 				  args->buffer_count, ret);
4134 		}
4135 	}
4136 
4137 	drm_free_large(exec2_list);
4138 	return ret;
4139 }
4140 
4141 int
4142 i915_gem_object_pin(struct drm_gem_object *obj, uint32_t alignment)
4143 {
4144 	struct drm_device *dev = obj->dev;
4145 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
4146 	int ret;
4147 
4148 	BUG_ON(obj_priv->pin_count == DRM_I915_GEM_OBJECT_MAX_PIN_COUNT);
4149 
4150 	i915_verify_inactive(dev, __FILE__, __LINE__);
4151 
4152 	if (obj_priv->gtt_space != NULL) {
4153 		if (alignment == 0)
4154 			alignment = i915_gem_get_gtt_alignment(obj);
4155 		if (obj_priv->gtt_offset & (alignment - 1)) {
4156 			ret = i915_gem_object_unbind(obj);
4157 			if (ret)
4158 				return ret;
4159 		}
4160 	}
4161 
4162 	if (obj_priv->gtt_space == NULL) {
4163 		ret = i915_gem_object_bind_to_gtt(obj, alignment);
4164 		if (ret)
4165 			return ret;
4166 	}
4167 
4168 	obj_priv->pin_count++;
4169 
4170 	/* If the object is not active and not pending a flush,
4171 	 * remove it from the inactive list
4172 	 */
4173 	if (obj_priv->pin_count == 1) {
4174 		atomic_inc(&dev->pin_count);
4175 		atomic_add(obj->size, &dev->pin_memory);
4176 		if (!obj_priv->active &&
4177 		    (obj->write_domain & I915_GEM_GPU_DOMAINS) == 0 &&
4178 		    !list_empty(&obj_priv->list))
4179 			list_del_init(&obj_priv->list);
4180 	}
4181 	i915_verify_inactive(dev, __FILE__, __LINE__);
4182 
4183 	return 0;
4184 }
4185 
4186 void
4187 i915_gem_object_unpin(struct drm_gem_object *obj)
4188 {
4189 	struct drm_device *dev = obj->dev;
4190 	drm_i915_private_t *dev_priv = dev->dev_private;
4191 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
4192 
4193 	i915_verify_inactive(dev, __FILE__, __LINE__);
4194 	obj_priv->pin_count--;
4195 	BUG_ON(obj_priv->pin_count < 0);
4196 	BUG_ON(obj_priv->gtt_space == NULL);
4197 
4198 	/* If the object is no longer pinned, and is
4199 	 * neither active nor being flushed, then stick it on
4200 	 * the inactive list
4201 	 */
4202 	if (obj_priv->pin_count == 0) {
4203 		if (!obj_priv->active &&
4204 		    (obj->write_domain & I915_GEM_GPU_DOMAINS) == 0)
4205 			list_move_tail(&obj_priv->list,
4206 				       &dev_priv->mm.inactive_list);
4207 		atomic_dec(&dev->pin_count);
4208 		atomic_sub(obj->size, &dev->pin_memory);
4209 	}
4210 	i915_verify_inactive(dev, __FILE__, __LINE__);
4211 }
4212 
4213 int
4214 i915_gem_pin_ioctl(struct drm_device *dev, void *data,
4215 		   struct drm_file *file_priv)
4216 {
4217 	struct drm_i915_gem_pin *args = data;
4218 	struct drm_gem_object *obj;
4219 	struct drm_i915_gem_object *obj_priv;
4220 	int ret;
4221 
4222 	mutex_lock(&dev->struct_mutex);
4223 
4224 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
4225 	if (obj == NULL) {
4226 		DRM_ERROR("Bad handle in i915_gem_pin_ioctl(): %d\n",
4227 			  args->handle);
4228 		mutex_unlock(&dev->struct_mutex);
4229 		return -EBADF;
4230 	}
4231 	obj_priv = to_intel_bo(obj);
4232 
4233 	if (obj_priv->madv != I915_MADV_WILLNEED) {
4234 		DRM_ERROR("Attempting to pin a purgeable buffer\n");
4235 		drm_gem_object_unreference(obj);
4236 		mutex_unlock(&dev->struct_mutex);
4237 		return -EINVAL;
4238 	}
4239 
4240 	if (obj_priv->pin_filp != NULL && obj_priv->pin_filp != file_priv) {
4241 		DRM_ERROR("Already pinned in i915_gem_pin_ioctl(): %d\n",
4242 			  args->handle);
4243 		drm_gem_object_unreference(obj);
4244 		mutex_unlock(&dev->struct_mutex);
4245 		return -EINVAL;
4246 	}
4247 
4248 	obj_priv->user_pin_count++;
4249 	obj_priv->pin_filp = file_priv;
4250 	if (obj_priv->user_pin_count == 1) {
4251 		ret = i915_gem_object_pin(obj, args->alignment);
4252 		if (ret != 0) {
4253 			drm_gem_object_unreference(obj);
4254 			mutex_unlock(&dev->struct_mutex);
4255 			return ret;
4256 		}
4257 	}
4258 
4259 	/* XXX - flush the CPU caches for pinned objects
4260 	 * as the X server doesn't manage domains yet
4261 	 */
4262 	i915_gem_object_flush_cpu_write_domain(obj);
4263 	args->offset = obj_priv->gtt_offset;
4264 	drm_gem_object_unreference(obj);
4265 	mutex_unlock(&dev->struct_mutex);
4266 
4267 	return 0;
4268 }
4269 
4270 int
4271 i915_gem_unpin_ioctl(struct drm_device *dev, void *data,
4272 		     struct drm_file *file_priv)
4273 {
4274 	struct drm_i915_gem_pin *args = data;
4275 	struct drm_gem_object *obj;
4276 	struct drm_i915_gem_object *obj_priv;
4277 
4278 	mutex_lock(&dev->struct_mutex);
4279 
4280 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
4281 	if (obj == NULL) {
4282 		DRM_ERROR("Bad handle in i915_gem_unpin_ioctl(): %d\n",
4283 			  args->handle);
4284 		mutex_unlock(&dev->struct_mutex);
4285 		return -EBADF;
4286 	}
4287 
4288 	obj_priv = to_intel_bo(obj);
4289 	if (obj_priv->pin_filp != file_priv) {
4290 		DRM_ERROR("Not pinned by caller in i915_gem_pin_ioctl(): %d\n",
4291 			  args->handle);
4292 		drm_gem_object_unreference(obj);
4293 		mutex_unlock(&dev->struct_mutex);
4294 		return -EINVAL;
4295 	}
4296 	obj_priv->user_pin_count--;
4297 	if (obj_priv->user_pin_count == 0) {
4298 		obj_priv->pin_filp = NULL;
4299 		i915_gem_object_unpin(obj);
4300 	}
4301 
4302 	drm_gem_object_unreference(obj);
4303 	mutex_unlock(&dev->struct_mutex);
4304 	return 0;
4305 }
4306 
4307 int
4308 i915_gem_busy_ioctl(struct drm_device *dev, void *data,
4309 		    struct drm_file *file_priv)
4310 {
4311 	struct drm_i915_gem_busy *args = data;
4312 	struct drm_gem_object *obj;
4313 	struct drm_i915_gem_object *obj_priv;
4314 	drm_i915_private_t *dev_priv = dev->dev_private;
4315 
4316 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
4317 	if (obj == NULL) {
4318 		DRM_ERROR("Bad handle in i915_gem_busy_ioctl(): %d\n",
4319 			  args->handle);
4320 		return -EBADF;
4321 	}
4322 
4323 	mutex_lock(&dev->struct_mutex);
4324 	/* Update the active list for the hardware's current position.
4325 	 * Otherwise this only updates on a delayed timer or when irqs are
4326 	 * actually unmasked, and our working set ends up being larger than
4327 	 * required.
4328 	 */
4329 	i915_gem_retire_requests(dev, &dev_priv->render_ring);
4330 
4331 	if (HAS_BSD(dev))
4332 		i915_gem_retire_requests(dev, &dev_priv->bsd_ring);
4333 
4334 	obj_priv = to_intel_bo(obj);
4335 	/* Don't count being on the flushing list against the object being
4336 	 * done.  Otherwise, a buffer left on the flushing list but not getting
4337 	 * flushed (because nobody's flushing that domain) won't ever return
4338 	 * unbusy and get reused by libdrm's bo cache.  The other expected
4339 	 * consumer of this interface, OpenGL's occlusion queries, also specs
4340 	 * that the objects get unbusy "eventually" without any interference.
4341 	 */
4342 	args->busy = obj_priv->active && obj_priv->last_rendering_seqno != 0;
4343 
4344 	drm_gem_object_unreference(obj);
4345 	mutex_unlock(&dev->struct_mutex);
4346 	return 0;
4347 }
4348 
4349 int
4350 i915_gem_throttle_ioctl(struct drm_device *dev, void *data,
4351 			struct drm_file *file_priv)
4352 {
4353     return i915_gem_ring_throttle(dev, file_priv);
4354 }
4355 
4356 int
4357 i915_gem_madvise_ioctl(struct drm_device *dev, void *data,
4358 		       struct drm_file *file_priv)
4359 {
4360 	struct drm_i915_gem_madvise *args = data;
4361 	struct drm_gem_object *obj;
4362 	struct drm_i915_gem_object *obj_priv;
4363 
4364 	switch (args->madv) {
4365 	case I915_MADV_DONTNEED:
4366 	case I915_MADV_WILLNEED:
4367 	    break;
4368 	default:
4369 	    return -EINVAL;
4370 	}
4371 
4372 	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
4373 	if (obj == NULL) {
4374 		DRM_ERROR("Bad handle in i915_gem_madvise_ioctl(): %d\n",
4375 			  args->handle);
4376 		return -EBADF;
4377 	}
4378 
4379 	mutex_lock(&dev->struct_mutex);
4380 	obj_priv = to_intel_bo(obj);
4381 
4382 	if (obj_priv->pin_count) {
4383 		drm_gem_object_unreference(obj);
4384 		mutex_unlock(&dev->struct_mutex);
4385 
4386 		DRM_ERROR("Attempted i915_gem_madvise_ioctl() on a pinned object\n");
4387 		return -EINVAL;
4388 	}
4389 
4390 	if (obj_priv->madv != __I915_MADV_PURGED)
4391 		obj_priv->madv = args->madv;
4392 
4393 	/* if the object is no longer bound, discard its backing storage */
4394 	if (i915_gem_object_is_purgeable(obj_priv) &&
4395 	    obj_priv->gtt_space == NULL)
4396 		i915_gem_object_truncate(obj);
4397 
4398 	args->retained = obj_priv->madv != __I915_MADV_PURGED;
4399 
4400 	drm_gem_object_unreference(obj);
4401 	mutex_unlock(&dev->struct_mutex);
4402 
4403 	return 0;
4404 }
4405 
4406 struct drm_gem_object * i915_gem_alloc_object(struct drm_device *dev,
4407 					      size_t size)
4408 {
4409 	struct drm_i915_gem_object *obj;
4410 
4411 	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
4412 	if (obj == NULL)
4413 		return NULL;
4414 
4415 	if (drm_gem_object_init(dev, &obj->base, size) != 0) {
4416 		kfree(obj);
4417 		return NULL;
4418 	}
4419 
4420 	obj->base.write_domain = I915_GEM_DOMAIN_CPU;
4421 	obj->base.read_domains = I915_GEM_DOMAIN_CPU;
4422 
4423 	obj->agp_type = AGP_USER_MEMORY;
4424 	obj->base.driver_private = NULL;
4425 	obj->fence_reg = I915_FENCE_REG_NONE;
4426 	INIT_LIST_HEAD(&obj->list);
4427 	INIT_LIST_HEAD(&obj->gpu_write_list);
4428 	obj->madv = I915_MADV_WILLNEED;
4429 
4430 	trace_i915_gem_object_create(&obj->base);
4431 
4432 	return &obj->base;
4433 }
4434 
4435 int i915_gem_init_object(struct drm_gem_object *obj)
4436 {
4437 	BUG();
4438 
4439 	return 0;
4440 }
4441 
4442 void i915_gem_free_object(struct drm_gem_object *obj)
4443 {
4444 	struct drm_device *dev = obj->dev;
4445 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
4446 
4447 	trace_i915_gem_object_destroy(obj);
4448 
4449 	while (obj_priv->pin_count > 0)
4450 		i915_gem_object_unpin(obj);
4451 
4452 	if (obj_priv->phys_obj)
4453 		i915_gem_detach_phys_object(dev, obj);
4454 
4455 	i915_gem_object_unbind(obj);
4456 
4457 	if (obj_priv->mmap_offset)
4458 		i915_gem_free_mmap_offset(obj);
4459 
4460 	drm_gem_object_release(obj);
4461 
4462 	kfree(obj_priv->page_cpu_valid);
4463 	kfree(obj_priv->bit_17);
4464 	kfree(obj_priv);
4465 }
4466 
4467 /** Unbinds all inactive objects. */
4468 static int
4469 i915_gem_evict_from_inactive_list(struct drm_device *dev)
4470 {
4471 	drm_i915_private_t *dev_priv = dev->dev_private;
4472 
4473 	while (!list_empty(&dev_priv->mm.inactive_list)) {
4474 		struct drm_gem_object *obj;
4475 		int ret;
4476 
4477 		obj = &list_first_entry(&dev_priv->mm.inactive_list,
4478 					struct drm_i915_gem_object,
4479 					list)->base;
4480 
4481 		ret = i915_gem_object_unbind(obj);
4482 		if (ret != 0) {
4483 			DRM_ERROR("Error unbinding object: %d\n", ret);
4484 			return ret;
4485 		}
4486 	}
4487 
4488 	return 0;
4489 }
4490 
4491 int
4492 i915_gem_idle(struct drm_device *dev)
4493 {
4494 	drm_i915_private_t *dev_priv = dev->dev_private;
4495 	int ret;
4496 
4497 	mutex_lock(&dev->struct_mutex);
4498 
4499 	if (dev_priv->mm.suspended ||
4500 			(dev_priv->render_ring.gem_object == NULL) ||
4501 			(HAS_BSD(dev) &&
4502 			 dev_priv->bsd_ring.gem_object == NULL)) {
4503 		mutex_unlock(&dev->struct_mutex);
4504 		return 0;
4505 	}
4506 
4507 	ret = i915_gpu_idle(dev);
4508 	if (ret) {
4509 		mutex_unlock(&dev->struct_mutex);
4510 		return ret;
4511 	}
4512 
4513 	/* Under UMS, be paranoid and evict. */
4514 	if (!drm_core_check_feature(dev, DRIVER_MODESET)) {
4515 		ret = i915_gem_evict_from_inactive_list(dev);
4516 		if (ret) {
4517 			mutex_unlock(&dev->struct_mutex);
4518 			return ret;
4519 		}
4520 	}
4521 
4522 	/* Hack!  Don't let anybody do execbuf while we don't control the chip.
4523 	 * We need to replace this with a semaphore, or something.
4524 	 * And not confound mm.suspended!
4525 	 */
4526 	dev_priv->mm.suspended = 1;
4527 	del_timer(&dev_priv->hangcheck_timer);
4528 
4529 	i915_kernel_lost_context(dev);
4530 	i915_gem_cleanup_ringbuffer(dev);
4531 
4532 	mutex_unlock(&dev->struct_mutex);
4533 
4534 	/* Cancel the retire work handler, which should be idle now. */
4535 	cancel_delayed_work_sync(&dev_priv->mm.retire_work);
4536 
4537 	return 0;
4538 }
4539 
4540 /*
4541  * 965+ support PIPE_CONTROL commands, which provide finer grained control
4542  * over cache flushing.
4543  */
4544 static int
4545 i915_gem_init_pipe_control(struct drm_device *dev)
4546 {
4547 	drm_i915_private_t *dev_priv = dev->dev_private;
4548 	struct drm_gem_object *obj;
4549 	struct drm_i915_gem_object *obj_priv;
4550 	int ret;
4551 
4552 	obj = i915_gem_alloc_object(dev, 4096);
4553 	if (obj == NULL) {
4554 		DRM_ERROR("Failed to allocate seqno page\n");
4555 		ret = -ENOMEM;
4556 		goto err;
4557 	}
4558 	obj_priv = to_intel_bo(obj);
4559 	obj_priv->agp_type = AGP_USER_CACHED_MEMORY;
4560 
4561 	ret = i915_gem_object_pin(obj, 4096);
4562 	if (ret)
4563 		goto err_unref;
4564 
4565 	dev_priv->seqno_gfx_addr = obj_priv->gtt_offset;
4566 	dev_priv->seqno_page =  kmap(obj_priv->pages[0]);
4567 	if (dev_priv->seqno_page == NULL)
4568 		goto err_unpin;
4569 
4570 	dev_priv->seqno_obj = obj;
4571 	memset(dev_priv->seqno_page, 0, PAGE_SIZE);
4572 
4573 	return 0;
4574 
4575 err_unpin:
4576 	i915_gem_object_unpin(obj);
4577 err_unref:
4578 	drm_gem_object_unreference(obj);
4579 err:
4580 	return ret;
4581 }
4582 
4583 
4584 static void
4585 i915_gem_cleanup_pipe_control(struct drm_device *dev)
4586 {
4587 	drm_i915_private_t *dev_priv = dev->dev_private;
4588 	struct drm_gem_object *obj;
4589 	struct drm_i915_gem_object *obj_priv;
4590 
4591 	obj = dev_priv->seqno_obj;
4592 	obj_priv = to_intel_bo(obj);
4593 	kunmap(obj_priv->pages[0]);
4594 	i915_gem_object_unpin(obj);
4595 	drm_gem_object_unreference(obj);
4596 	dev_priv->seqno_obj = NULL;
4597 
4598 	dev_priv->seqno_page = NULL;
4599 }
4600 
4601 int
4602 i915_gem_init_ringbuffer(struct drm_device *dev)
4603 {
4604 	drm_i915_private_t *dev_priv = dev->dev_private;
4605 	int ret;
4606 
4607 	dev_priv->render_ring = render_ring;
4608 
4609 	if (!I915_NEED_GFX_HWS(dev)) {
4610 		dev_priv->render_ring.status_page.page_addr
4611 			= dev_priv->status_page_dmah->vaddr;
4612 		memset(dev_priv->render_ring.status_page.page_addr,
4613 				0, PAGE_SIZE);
4614 	}
4615 
4616 	if (HAS_PIPE_CONTROL(dev)) {
4617 		ret = i915_gem_init_pipe_control(dev);
4618 		if (ret)
4619 			return ret;
4620 	}
4621 
4622 	ret = intel_init_ring_buffer(dev, &dev_priv->render_ring);
4623 	if (ret)
4624 		goto cleanup_pipe_control;
4625 
4626 	if (HAS_BSD(dev)) {
4627 		dev_priv->bsd_ring = bsd_ring;
4628 		ret = intel_init_ring_buffer(dev, &dev_priv->bsd_ring);
4629 		if (ret)
4630 			goto cleanup_render_ring;
4631 	}
4632 
4633 	return 0;
4634 
4635 cleanup_render_ring:
4636 	intel_cleanup_ring_buffer(dev, &dev_priv->render_ring);
4637 cleanup_pipe_control:
4638 	if (HAS_PIPE_CONTROL(dev))
4639 		i915_gem_cleanup_pipe_control(dev);
4640 	return ret;
4641 }
4642 
4643 void
4644 i915_gem_cleanup_ringbuffer(struct drm_device *dev)
4645 {
4646 	drm_i915_private_t *dev_priv = dev->dev_private;
4647 
4648 	intel_cleanup_ring_buffer(dev, &dev_priv->render_ring);
4649 	if (HAS_BSD(dev))
4650 		intel_cleanup_ring_buffer(dev, &dev_priv->bsd_ring);
4651 	if (HAS_PIPE_CONTROL(dev))
4652 		i915_gem_cleanup_pipe_control(dev);
4653 }
4654 
4655 int
4656 i915_gem_entervt_ioctl(struct drm_device *dev, void *data,
4657 		       struct drm_file *file_priv)
4658 {
4659 	drm_i915_private_t *dev_priv = dev->dev_private;
4660 	int ret;
4661 
4662 	if (drm_core_check_feature(dev, DRIVER_MODESET))
4663 		return 0;
4664 
4665 	if (atomic_read(&dev_priv->mm.wedged)) {
4666 		DRM_ERROR("Reenabling wedged hardware, good luck\n");
4667 		atomic_set(&dev_priv->mm.wedged, 0);
4668 	}
4669 
4670 	mutex_lock(&dev->struct_mutex);
4671 	dev_priv->mm.suspended = 0;
4672 
4673 	ret = i915_gem_init_ringbuffer(dev);
4674 	if (ret != 0) {
4675 		mutex_unlock(&dev->struct_mutex);
4676 		return ret;
4677 	}
4678 
4679 	spin_lock(&dev_priv->mm.active_list_lock);
4680 	BUG_ON(!list_empty(&dev_priv->render_ring.active_list));
4681 	BUG_ON(HAS_BSD(dev) && !list_empty(&dev_priv->bsd_ring.active_list));
4682 	spin_unlock(&dev_priv->mm.active_list_lock);
4683 
4684 	BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
4685 	BUG_ON(!list_empty(&dev_priv->mm.inactive_list));
4686 	BUG_ON(!list_empty(&dev_priv->render_ring.request_list));
4687 	BUG_ON(HAS_BSD(dev) && !list_empty(&dev_priv->bsd_ring.request_list));
4688 	mutex_unlock(&dev->struct_mutex);
4689 
4690 	drm_irq_install(dev);
4691 
4692 	return 0;
4693 }
4694 
4695 int
4696 i915_gem_leavevt_ioctl(struct drm_device *dev, void *data,
4697 		       struct drm_file *file_priv)
4698 {
4699 	if (drm_core_check_feature(dev, DRIVER_MODESET))
4700 		return 0;
4701 
4702 	drm_irq_uninstall(dev);
4703 	return i915_gem_idle(dev);
4704 }
4705 
4706 void
4707 i915_gem_lastclose(struct drm_device *dev)
4708 {
4709 	int ret;
4710 
4711 	if (drm_core_check_feature(dev, DRIVER_MODESET))
4712 		return;
4713 
4714 	ret = i915_gem_idle(dev);
4715 	if (ret)
4716 		DRM_ERROR("failed to idle hardware: %d\n", ret);
4717 }
4718 
4719 void
4720 i915_gem_load(struct drm_device *dev)
4721 {
4722 	int i;
4723 	drm_i915_private_t *dev_priv = dev->dev_private;
4724 
4725 	spin_lock_init(&dev_priv->mm.active_list_lock);
4726 	INIT_LIST_HEAD(&dev_priv->mm.flushing_list);
4727 	INIT_LIST_HEAD(&dev_priv->mm.gpu_write_list);
4728 	INIT_LIST_HEAD(&dev_priv->mm.inactive_list);
4729 	INIT_LIST_HEAD(&dev_priv->mm.fence_list);
4730 	INIT_LIST_HEAD(&dev_priv->render_ring.active_list);
4731 	INIT_LIST_HEAD(&dev_priv->render_ring.request_list);
4732 	if (HAS_BSD(dev)) {
4733 		INIT_LIST_HEAD(&dev_priv->bsd_ring.active_list);
4734 		INIT_LIST_HEAD(&dev_priv->bsd_ring.request_list);
4735 	}
4736 	for (i = 0; i < 16; i++)
4737 		INIT_LIST_HEAD(&dev_priv->fence_regs[i].lru_list);
4738 	INIT_DELAYED_WORK(&dev_priv->mm.retire_work,
4739 			  i915_gem_retire_work_handler);
4740 	spin_lock(&shrink_list_lock);
4741 	list_add(&dev_priv->mm.shrink_list, &shrink_list);
4742 	spin_unlock(&shrink_list_lock);
4743 
4744 	/* Old X drivers will take 0-2 for front, back, depth buffers */
4745 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
4746 		dev_priv->fence_reg_start = 3;
4747 
4748 	if (IS_I965G(dev) || IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev))
4749 		dev_priv->num_fence_regs = 16;
4750 	else
4751 		dev_priv->num_fence_regs = 8;
4752 
4753 	/* Initialize fence registers to zero */
4754 	if (IS_I965G(dev)) {
4755 		for (i = 0; i < 16; i++)
4756 			I915_WRITE64(FENCE_REG_965_0 + (i * 8), 0);
4757 	} else {
4758 		for (i = 0; i < 8; i++)
4759 			I915_WRITE(FENCE_REG_830_0 + (i * 4), 0);
4760 		if (IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev))
4761 			for (i = 0; i < 8; i++)
4762 				I915_WRITE(FENCE_REG_945_8 + (i * 4), 0);
4763 	}
4764 	i915_gem_detect_bit_6_swizzle(dev);
4765 	init_waitqueue_head(&dev_priv->pending_flip_queue);
4766 }
4767 
4768 /*
4769  * Create a physically contiguous memory object for this object
4770  * e.g. for cursor + overlay regs
4771  */
4772 int i915_gem_init_phys_object(struct drm_device *dev,
4773 			      int id, int size)
4774 {
4775 	drm_i915_private_t *dev_priv = dev->dev_private;
4776 	struct drm_i915_gem_phys_object *phys_obj;
4777 	int ret;
4778 
4779 	if (dev_priv->mm.phys_objs[id - 1] || !size)
4780 		return 0;
4781 
4782 	phys_obj = kzalloc(sizeof(struct drm_i915_gem_phys_object), GFP_KERNEL);
4783 	if (!phys_obj)
4784 		return -ENOMEM;
4785 
4786 	phys_obj->id = id;
4787 
4788 	phys_obj->handle = drm_pci_alloc(dev, size, 0);
4789 	if (!phys_obj->handle) {
4790 		ret = -ENOMEM;
4791 		goto kfree_obj;
4792 	}
4793 #ifdef CONFIG_X86
4794 	set_memory_wc((unsigned long)phys_obj->handle->vaddr, phys_obj->handle->size / PAGE_SIZE);
4795 #endif
4796 
4797 	dev_priv->mm.phys_objs[id - 1] = phys_obj;
4798 
4799 	return 0;
4800 kfree_obj:
4801 	kfree(phys_obj);
4802 	return ret;
4803 }
4804 
4805 void i915_gem_free_phys_object(struct drm_device *dev, int id)
4806 {
4807 	drm_i915_private_t *dev_priv = dev->dev_private;
4808 	struct drm_i915_gem_phys_object *phys_obj;
4809 
4810 	if (!dev_priv->mm.phys_objs[id - 1])
4811 		return;
4812 
4813 	phys_obj = dev_priv->mm.phys_objs[id - 1];
4814 	if (phys_obj->cur_obj) {
4815 		i915_gem_detach_phys_object(dev, phys_obj->cur_obj);
4816 	}
4817 
4818 #ifdef CONFIG_X86
4819 	set_memory_wb((unsigned long)phys_obj->handle->vaddr, phys_obj->handle->size / PAGE_SIZE);
4820 #endif
4821 	drm_pci_free(dev, phys_obj->handle);
4822 	kfree(phys_obj);
4823 	dev_priv->mm.phys_objs[id - 1] = NULL;
4824 }
4825 
4826 void i915_gem_free_all_phys_object(struct drm_device *dev)
4827 {
4828 	int i;
4829 
4830 	for (i = I915_GEM_PHYS_CURSOR_0; i <= I915_MAX_PHYS_OBJECT; i++)
4831 		i915_gem_free_phys_object(dev, i);
4832 }
4833 
4834 void i915_gem_detach_phys_object(struct drm_device *dev,
4835 				 struct drm_gem_object *obj)
4836 {
4837 	struct drm_i915_gem_object *obj_priv;
4838 	int i;
4839 	int ret;
4840 	int page_count;
4841 
4842 	obj_priv = to_intel_bo(obj);
4843 	if (!obj_priv->phys_obj)
4844 		return;
4845 
4846 	ret = i915_gem_object_get_pages(obj, 0);
4847 	if (ret)
4848 		goto out;
4849 
4850 	page_count = obj->size / PAGE_SIZE;
4851 
4852 	for (i = 0; i < page_count; i++) {
4853 		char *dst = kmap_atomic(obj_priv->pages[i], KM_USER0);
4854 		char *src = obj_priv->phys_obj->handle->vaddr + (i * PAGE_SIZE);
4855 
4856 		memcpy(dst, src, PAGE_SIZE);
4857 		kunmap_atomic(dst, KM_USER0);
4858 	}
4859 	drm_clflush_pages(obj_priv->pages, page_count);
4860 	drm_agp_chipset_flush(dev);
4861 
4862 	i915_gem_object_put_pages(obj);
4863 out:
4864 	obj_priv->phys_obj->cur_obj = NULL;
4865 	obj_priv->phys_obj = NULL;
4866 }
4867 
4868 int
4869 i915_gem_attach_phys_object(struct drm_device *dev,
4870 			    struct drm_gem_object *obj, int id)
4871 {
4872 	drm_i915_private_t *dev_priv = dev->dev_private;
4873 	struct drm_i915_gem_object *obj_priv;
4874 	int ret = 0;
4875 	int page_count;
4876 	int i;
4877 
4878 	if (id > I915_MAX_PHYS_OBJECT)
4879 		return -EINVAL;
4880 
4881 	obj_priv = to_intel_bo(obj);
4882 
4883 	if (obj_priv->phys_obj) {
4884 		if (obj_priv->phys_obj->id == id)
4885 			return 0;
4886 		i915_gem_detach_phys_object(dev, obj);
4887 	}
4888 
4889 
4890 	/* create a new object */
4891 	if (!dev_priv->mm.phys_objs[id - 1]) {
4892 		ret = i915_gem_init_phys_object(dev, id,
4893 						obj->size);
4894 		if (ret) {
4895 			DRM_ERROR("failed to init phys object %d size: %zu\n", id, obj->size);
4896 			goto out;
4897 		}
4898 	}
4899 
4900 	/* bind to the object */
4901 	obj_priv->phys_obj = dev_priv->mm.phys_objs[id - 1];
4902 	obj_priv->phys_obj->cur_obj = obj;
4903 
4904 	ret = i915_gem_object_get_pages(obj, 0);
4905 	if (ret) {
4906 		DRM_ERROR("failed to get page list\n");
4907 		goto out;
4908 	}
4909 
4910 	page_count = obj->size / PAGE_SIZE;
4911 
4912 	for (i = 0; i < page_count; i++) {
4913 		char *src = kmap_atomic(obj_priv->pages[i], KM_USER0);
4914 		char *dst = obj_priv->phys_obj->handle->vaddr + (i * PAGE_SIZE);
4915 
4916 		memcpy(dst, src, PAGE_SIZE);
4917 		kunmap_atomic(src, KM_USER0);
4918 	}
4919 
4920 	i915_gem_object_put_pages(obj);
4921 
4922 	return 0;
4923 out:
4924 	return ret;
4925 }
4926 
4927 static int
4928 i915_gem_phys_pwrite(struct drm_device *dev, struct drm_gem_object *obj,
4929 		     struct drm_i915_gem_pwrite *args,
4930 		     struct drm_file *file_priv)
4931 {
4932 	struct drm_i915_gem_object *obj_priv = to_intel_bo(obj);
4933 	void *obj_addr;
4934 	int ret;
4935 	char __user *user_data;
4936 
4937 	user_data = (char __user *) (uintptr_t) args->data_ptr;
4938 	obj_addr = obj_priv->phys_obj->handle->vaddr + args->offset;
4939 
4940 	DRM_DEBUG_DRIVER("obj_addr %p, %lld\n", obj_addr, args->size);
4941 	ret = copy_from_user(obj_addr, user_data, args->size);
4942 	if (ret)
4943 		return -EFAULT;
4944 
4945 	drm_agp_chipset_flush(dev);
4946 	return 0;
4947 }
4948 
4949 void i915_gem_release(struct drm_device * dev, struct drm_file *file_priv)
4950 {
4951 	struct drm_i915_file_private *i915_file_priv = file_priv->driver_priv;
4952 
4953 	/* Clean up our request list when the client is going away, so that
4954 	 * later retire_requests won't dereference our soon-to-be-gone
4955 	 * file_priv.
4956 	 */
4957 	mutex_lock(&dev->struct_mutex);
4958 	while (!list_empty(&i915_file_priv->mm.request_list))
4959 		list_del_init(i915_file_priv->mm.request_list.next);
4960 	mutex_unlock(&dev->struct_mutex);
4961 }
4962 
4963 static int
4964 i915_gpu_is_active(struct drm_device *dev)
4965 {
4966 	drm_i915_private_t *dev_priv = dev->dev_private;
4967 	int lists_empty;
4968 
4969 	spin_lock(&dev_priv->mm.active_list_lock);
4970 	lists_empty = list_empty(&dev_priv->mm.flushing_list) &&
4971 		      list_empty(&dev_priv->render_ring.active_list);
4972 	if (HAS_BSD(dev))
4973 		lists_empty &= list_empty(&dev_priv->bsd_ring.active_list);
4974 	spin_unlock(&dev_priv->mm.active_list_lock);
4975 
4976 	return !lists_empty;
4977 }
4978 
4979 static int
4980 i915_gem_shrink(int nr_to_scan, gfp_t gfp_mask)
4981 {
4982 	drm_i915_private_t *dev_priv, *next_dev;
4983 	struct drm_i915_gem_object *obj_priv, *next_obj;
4984 	int cnt = 0;
4985 	int would_deadlock = 1;
4986 
4987 	/* "fast-path" to count number of available objects */
4988 	if (nr_to_scan == 0) {
4989 		spin_lock(&shrink_list_lock);
4990 		list_for_each_entry(dev_priv, &shrink_list, mm.shrink_list) {
4991 			struct drm_device *dev = dev_priv->dev;
4992 
4993 			if (mutex_trylock(&dev->struct_mutex)) {
4994 				list_for_each_entry(obj_priv,
4995 						    &dev_priv->mm.inactive_list,
4996 						    list)
4997 					cnt++;
4998 				mutex_unlock(&dev->struct_mutex);
4999 			}
5000 		}
5001 		spin_unlock(&shrink_list_lock);
5002 
5003 		return (cnt / 100) * sysctl_vfs_cache_pressure;
5004 	}
5005 
5006 	spin_lock(&shrink_list_lock);
5007 
5008 rescan:
5009 	/* first scan for clean buffers */
5010 	list_for_each_entry_safe(dev_priv, next_dev,
5011 				 &shrink_list, mm.shrink_list) {
5012 		struct drm_device *dev = dev_priv->dev;
5013 
5014 		if (! mutex_trylock(&dev->struct_mutex))
5015 			continue;
5016 
5017 		spin_unlock(&shrink_list_lock);
5018 		i915_gem_retire_requests(dev, &dev_priv->render_ring);
5019 
5020 		if (HAS_BSD(dev))
5021 			i915_gem_retire_requests(dev, &dev_priv->bsd_ring);
5022 
5023 		list_for_each_entry_safe(obj_priv, next_obj,
5024 					 &dev_priv->mm.inactive_list,
5025 					 list) {
5026 			if (i915_gem_object_is_purgeable(obj_priv)) {
5027 				i915_gem_object_unbind(&obj_priv->base);
5028 				if (--nr_to_scan <= 0)
5029 					break;
5030 			}
5031 		}
5032 
5033 		spin_lock(&shrink_list_lock);
5034 		mutex_unlock(&dev->struct_mutex);
5035 
5036 		would_deadlock = 0;
5037 
5038 		if (nr_to_scan <= 0)
5039 			break;
5040 	}
5041 
5042 	/* second pass, evict/count anything still on the inactive list */
5043 	list_for_each_entry_safe(dev_priv, next_dev,
5044 				 &shrink_list, mm.shrink_list) {
5045 		struct drm_device *dev = dev_priv->dev;
5046 
5047 		if (! mutex_trylock(&dev->struct_mutex))
5048 			continue;
5049 
5050 		spin_unlock(&shrink_list_lock);
5051 
5052 		list_for_each_entry_safe(obj_priv, next_obj,
5053 					 &dev_priv->mm.inactive_list,
5054 					 list) {
5055 			if (nr_to_scan > 0) {
5056 				i915_gem_object_unbind(&obj_priv->base);
5057 				nr_to_scan--;
5058 			} else
5059 				cnt++;
5060 		}
5061 
5062 		spin_lock(&shrink_list_lock);
5063 		mutex_unlock(&dev->struct_mutex);
5064 
5065 		would_deadlock = 0;
5066 	}
5067 
5068 	if (nr_to_scan) {
5069 		int active = 0;
5070 
5071 		/*
5072 		 * We are desperate for pages, so as a last resort, wait
5073 		 * for the GPU to finish and discard whatever we can.
5074 		 * This has a dramatic impact to reduce the number of
5075 		 * OOM-killer events whilst running the GPU aggressively.
5076 		 */
5077 		list_for_each_entry(dev_priv, &shrink_list, mm.shrink_list) {
5078 			struct drm_device *dev = dev_priv->dev;
5079 
5080 			if (!mutex_trylock(&dev->struct_mutex))
5081 				continue;
5082 
5083 			spin_unlock(&shrink_list_lock);
5084 
5085 			if (i915_gpu_is_active(dev)) {
5086 				i915_gpu_idle(dev);
5087 				active++;
5088 			}
5089 
5090 			spin_lock(&shrink_list_lock);
5091 			mutex_unlock(&dev->struct_mutex);
5092 		}
5093 
5094 		if (active)
5095 			goto rescan;
5096 	}
5097 
5098 	spin_unlock(&shrink_list_lock);
5099 
5100 	if (would_deadlock)
5101 		return -1;
5102 	else if (cnt > 0)
5103 		return (cnt / 100) * sysctl_vfs_cache_pressure;
5104 	else
5105 		return 0;
5106 }
5107 
5108 static struct shrinker shrinker = {
5109 	.shrink = i915_gem_shrink,
5110 	.seeks = DEFAULT_SEEKS,
5111 };
5112 
5113 __init void
5114 i915_gem_shrinker_init(void)
5115 {
5116     register_shrinker(&shrinker);
5117 }
5118 
5119 __exit void
5120 i915_gem_shrinker_exit(void)
5121 {
5122     unregister_shrinker(&shrinker);
5123 }
5124