Merge branch 'mmci' into fixes
[pandora-kernel.git] / drivers / gpu / drm / i915 / i915_gem.c
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 __must_check int i915_gem_object_flush_gpu_write_domain(struct drm_i915_gem_object *obj);
39 static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj);
40 static void i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj);
41 static __must_check int i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj,
42                                                           bool write);
43 static __must_check int i915_gem_object_set_cpu_read_domain_range(struct drm_i915_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_i915_gem_object *obj);
47 static __must_check int i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
48                                                     unsigned alignment,
49                                                     bool map_and_fenceable);
50 static void i915_gem_clear_fence_reg(struct drm_device *dev,
51                                      struct drm_i915_fence_reg *reg);
52 static int i915_gem_phys_pwrite(struct drm_device *dev,
53                                 struct drm_i915_gem_object *obj,
54                                 struct drm_i915_gem_pwrite *args,
55                                 struct drm_file *file);
56 static void i915_gem_free_object_tail(struct drm_i915_gem_object *obj);
57
58 static int i915_gem_inactive_shrink(struct shrinker *shrinker,
59                                     int nr_to_scan,
60                                     gfp_t gfp_mask);
61
62
63 /* some bookkeeping */
64 static void i915_gem_info_add_obj(struct drm_i915_private *dev_priv,
65                                   size_t size)
66 {
67         dev_priv->mm.object_count++;
68         dev_priv->mm.object_memory += size;
69 }
70
71 static void i915_gem_info_remove_obj(struct drm_i915_private *dev_priv,
72                                      size_t size)
73 {
74         dev_priv->mm.object_count--;
75         dev_priv->mm.object_memory -= size;
76 }
77
78 int
79 i915_gem_check_is_wedged(struct drm_device *dev)
80 {
81         struct drm_i915_private *dev_priv = dev->dev_private;
82         struct completion *x = &dev_priv->error_completion;
83         unsigned long flags;
84         int ret;
85
86         if (!atomic_read(&dev_priv->mm.wedged))
87                 return 0;
88
89         ret = wait_for_completion_interruptible(x);
90         if (ret)
91                 return ret;
92
93         /* Success, we reset the GPU! */
94         if (!atomic_read(&dev_priv->mm.wedged))
95                 return 0;
96
97         /* GPU is hung, bump the completion count to account for
98          * the token we just consumed so that we never hit zero and
99          * end up waiting upon a subsequent completion event that
100          * will never happen.
101          */
102         spin_lock_irqsave(&x->wait.lock, flags);
103         x->done++;
104         spin_unlock_irqrestore(&x->wait.lock, flags);
105         return -EIO;
106 }
107
108 int i915_mutex_lock_interruptible(struct drm_device *dev)
109 {
110         struct drm_i915_private *dev_priv = dev->dev_private;
111         int ret;
112
113         ret = i915_gem_check_is_wedged(dev);
114         if (ret)
115                 return ret;
116
117         ret = mutex_lock_interruptible(&dev->struct_mutex);
118         if (ret)
119                 return ret;
120
121         if (atomic_read(&dev_priv->mm.wedged)) {
122                 mutex_unlock(&dev->struct_mutex);
123                 return -EAGAIN;
124         }
125
126         WARN_ON(i915_verify_lists(dev));
127         return 0;
128 }
129
130 static inline bool
131 i915_gem_object_is_inactive(struct drm_i915_gem_object *obj)
132 {
133         return obj->gtt_space && !obj->active && obj->pin_count == 0;
134 }
135
136 void i915_gem_do_init(struct drm_device *dev,
137                       unsigned long start,
138                       unsigned long mappable_end,
139                       unsigned long end)
140 {
141         drm_i915_private_t *dev_priv = dev->dev_private;
142
143         drm_mm_init(&dev_priv->mm.gtt_space, start,
144                     end - start);
145
146         dev_priv->mm.gtt_total = end - start;
147         dev_priv->mm.mappable_gtt_total = min(end, mappable_end) - start;
148         dev_priv->mm.gtt_mappable_end = mappable_end;
149 }
150
151 int
152 i915_gem_init_ioctl(struct drm_device *dev, void *data,
153                     struct drm_file *file)
154 {
155         struct drm_i915_gem_init *args = data;
156
157         if (args->gtt_start >= args->gtt_end ||
158             (args->gtt_end | args->gtt_start) & (PAGE_SIZE - 1))
159                 return -EINVAL;
160
161         mutex_lock(&dev->struct_mutex);
162         i915_gem_do_init(dev, args->gtt_start, args->gtt_end, args->gtt_end);
163         mutex_unlock(&dev->struct_mutex);
164
165         return 0;
166 }
167
168 int
169 i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data,
170                             struct drm_file *file)
171 {
172         struct drm_i915_private *dev_priv = dev->dev_private;
173         struct drm_i915_gem_get_aperture *args = data;
174         struct drm_i915_gem_object *obj;
175         size_t pinned;
176
177         if (!(dev->driver->driver_features & DRIVER_GEM))
178                 return -ENODEV;
179
180         pinned = 0;
181         mutex_lock(&dev->struct_mutex);
182         list_for_each_entry(obj, &dev_priv->mm.pinned_list, mm_list)
183                 pinned += obj->gtt_space->size;
184         mutex_unlock(&dev->struct_mutex);
185
186         args->aper_size = dev_priv->mm.gtt_total;
187         args->aper_available_size = args->aper_size -pinned;
188
189         return 0;
190 }
191
192 /**
193  * Creates a new mm object and returns a handle to it.
194  */
195 int
196 i915_gem_create_ioctl(struct drm_device *dev, void *data,
197                       struct drm_file *file)
198 {
199         struct drm_i915_gem_create *args = data;
200         struct drm_i915_gem_object *obj;
201         int ret;
202         u32 handle;
203
204         args->size = roundup(args->size, PAGE_SIZE);
205
206         /* Allocate the new object */
207         obj = i915_gem_alloc_object(dev, args->size);
208         if (obj == NULL)
209                 return -ENOMEM;
210
211         ret = drm_gem_handle_create(file, &obj->base, &handle);
212         if (ret) {
213                 drm_gem_object_release(&obj->base);
214                 i915_gem_info_remove_obj(dev->dev_private, obj->base.size);
215                 kfree(obj);
216                 return ret;
217         }
218
219         /* drop reference from allocate - handle holds it now */
220         drm_gem_object_unreference(&obj->base);
221         trace_i915_gem_object_create(obj);
222
223         args->handle = handle;
224         return 0;
225 }
226
227 static int i915_gem_object_needs_bit17_swizzle(struct drm_i915_gem_object *obj)
228 {
229         drm_i915_private_t *dev_priv = obj->base.dev->dev_private;
230
231         return dev_priv->mm.bit_6_swizzle_x == I915_BIT_6_SWIZZLE_9_10_17 &&
232                 obj->tiling_mode != I915_TILING_NONE;
233 }
234
235 static inline void
236 slow_shmem_copy(struct page *dst_page,
237                 int dst_offset,
238                 struct page *src_page,
239                 int src_offset,
240                 int length)
241 {
242         char *dst_vaddr, *src_vaddr;
243
244         dst_vaddr = kmap(dst_page);
245         src_vaddr = kmap(src_page);
246
247         memcpy(dst_vaddr + dst_offset, src_vaddr + src_offset, length);
248
249         kunmap(src_page);
250         kunmap(dst_page);
251 }
252
253 static inline void
254 slow_shmem_bit17_copy(struct page *gpu_page,
255                       int gpu_offset,
256                       struct page *cpu_page,
257                       int cpu_offset,
258                       int length,
259                       int is_read)
260 {
261         char *gpu_vaddr, *cpu_vaddr;
262
263         /* Use the unswizzled path if this page isn't affected. */
264         if ((page_to_phys(gpu_page) & (1 << 17)) == 0) {
265                 if (is_read)
266                         return slow_shmem_copy(cpu_page, cpu_offset,
267                                                gpu_page, gpu_offset, length);
268                 else
269                         return slow_shmem_copy(gpu_page, gpu_offset,
270                                                cpu_page, cpu_offset, length);
271         }
272
273         gpu_vaddr = kmap(gpu_page);
274         cpu_vaddr = kmap(cpu_page);
275
276         /* Copy the data, XORing A6 with A17 (1). The user already knows he's
277          * XORing with the other bits (A9 for Y, A9 and A10 for X)
278          */
279         while (length > 0) {
280                 int cacheline_end = ALIGN(gpu_offset + 1, 64);
281                 int this_length = min(cacheline_end - gpu_offset, length);
282                 int swizzled_gpu_offset = gpu_offset ^ 64;
283
284                 if (is_read) {
285                         memcpy(cpu_vaddr + cpu_offset,
286                                gpu_vaddr + swizzled_gpu_offset,
287                                this_length);
288                 } else {
289                         memcpy(gpu_vaddr + swizzled_gpu_offset,
290                                cpu_vaddr + cpu_offset,
291                                this_length);
292                 }
293                 cpu_offset += this_length;
294                 gpu_offset += this_length;
295                 length -= this_length;
296         }
297
298         kunmap(cpu_page);
299         kunmap(gpu_page);
300 }
301
302 /**
303  * This is the fast shmem pread path, which attempts to copy_from_user directly
304  * from the backing pages of the object to the user's address space.  On a
305  * fault, it fails so we can fall back to i915_gem_shmem_pwrite_slow().
306  */
307 static int
308 i915_gem_shmem_pread_fast(struct drm_device *dev,
309                           struct drm_i915_gem_object *obj,
310                           struct drm_i915_gem_pread *args,
311                           struct drm_file *file)
312 {
313         struct address_space *mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping;
314         ssize_t remain;
315         loff_t offset;
316         char __user *user_data;
317         int page_offset, page_length;
318
319         user_data = (char __user *) (uintptr_t) args->data_ptr;
320         remain = args->size;
321
322         offset = args->offset;
323
324         while (remain > 0) {
325                 struct page *page;
326                 char *vaddr;
327                 int ret;
328
329                 /* Operation in this page
330                  *
331                  * page_offset = offset within page
332                  * page_length = bytes to copy for this page
333                  */
334                 page_offset = offset & (PAGE_SIZE-1);
335                 page_length = remain;
336                 if ((page_offset + remain) > PAGE_SIZE)
337                         page_length = PAGE_SIZE - page_offset;
338
339                 page = read_cache_page_gfp(mapping, offset >> PAGE_SHIFT,
340                                            GFP_HIGHUSER | __GFP_RECLAIMABLE);
341                 if (IS_ERR(page))
342                         return PTR_ERR(page);
343
344                 vaddr = kmap_atomic(page);
345                 ret = __copy_to_user_inatomic(user_data,
346                                               vaddr + page_offset,
347                                               page_length);
348                 kunmap_atomic(vaddr);
349
350                 mark_page_accessed(page);
351                 page_cache_release(page);
352                 if (ret)
353                         return -EFAULT;
354
355                 remain -= page_length;
356                 user_data += page_length;
357                 offset += page_length;
358         }
359
360         return 0;
361 }
362
363 /**
364  * This is the fallback shmem pread path, which allocates temporary storage
365  * in kernel space to copy_to_user into outside of the struct_mutex, so we
366  * can copy out of the object's backing pages while holding the struct mutex
367  * and not take page faults.
368  */
369 static int
370 i915_gem_shmem_pread_slow(struct drm_device *dev,
371                           struct drm_i915_gem_object *obj,
372                           struct drm_i915_gem_pread *args,
373                           struct drm_file *file)
374 {
375         struct address_space *mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping;
376         struct mm_struct *mm = current->mm;
377         struct page **user_pages;
378         ssize_t remain;
379         loff_t offset, pinned_pages, i;
380         loff_t first_data_page, last_data_page, num_pages;
381         int shmem_page_offset;
382         int data_page_index, data_page_offset;
383         int page_length;
384         int ret;
385         uint64_t data_ptr = args->data_ptr;
386         int do_bit17_swizzling;
387
388         remain = args->size;
389
390         /* Pin the user pages containing the data.  We can't fault while
391          * holding the struct mutex, yet we want to hold it while
392          * dereferencing the user data.
393          */
394         first_data_page = data_ptr / PAGE_SIZE;
395         last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE;
396         num_pages = last_data_page - first_data_page + 1;
397
398         user_pages = drm_malloc_ab(num_pages, sizeof(struct page *));
399         if (user_pages == NULL)
400                 return -ENOMEM;
401
402         mutex_unlock(&dev->struct_mutex);
403         down_read(&mm->mmap_sem);
404         pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr,
405                                       num_pages, 1, 0, user_pages, NULL);
406         up_read(&mm->mmap_sem);
407         mutex_lock(&dev->struct_mutex);
408         if (pinned_pages < num_pages) {
409                 ret = -EFAULT;
410                 goto out;
411         }
412
413         ret = i915_gem_object_set_cpu_read_domain_range(obj,
414                                                         args->offset,
415                                                         args->size);
416         if (ret)
417                 goto out;
418
419         do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj);
420
421         offset = args->offset;
422
423         while (remain > 0) {
424                 struct page *page;
425
426                 /* Operation in this page
427                  *
428                  * shmem_page_offset = offset within page in shmem file
429                  * data_page_index = page number in get_user_pages return
430                  * data_page_offset = offset with data_page_index page.
431                  * page_length = bytes to copy for this page
432                  */
433                 shmem_page_offset = offset & ~PAGE_MASK;
434                 data_page_index = data_ptr / PAGE_SIZE - first_data_page;
435                 data_page_offset = data_ptr & ~PAGE_MASK;
436
437                 page_length = remain;
438                 if ((shmem_page_offset + page_length) > PAGE_SIZE)
439                         page_length = PAGE_SIZE - shmem_page_offset;
440                 if ((data_page_offset + page_length) > PAGE_SIZE)
441                         page_length = PAGE_SIZE - data_page_offset;
442
443                 page = read_cache_page_gfp(mapping, offset >> PAGE_SHIFT,
444                                            GFP_HIGHUSER | __GFP_RECLAIMABLE);
445                 if (IS_ERR(page))
446                         return PTR_ERR(page);
447
448                 if (do_bit17_swizzling) {
449                         slow_shmem_bit17_copy(page,
450                                               shmem_page_offset,
451                                               user_pages[data_page_index],
452                                               data_page_offset,
453                                               page_length,
454                                               1);
455                 } else {
456                         slow_shmem_copy(user_pages[data_page_index],
457                                         data_page_offset,
458                                         page,
459                                         shmem_page_offset,
460                                         page_length);
461                 }
462
463                 mark_page_accessed(page);
464                 page_cache_release(page);
465
466                 remain -= page_length;
467                 data_ptr += page_length;
468                 offset += page_length;
469         }
470
471 out:
472         for (i = 0; i < pinned_pages; i++) {
473                 SetPageDirty(user_pages[i]);
474                 mark_page_accessed(user_pages[i]);
475                 page_cache_release(user_pages[i]);
476         }
477         drm_free_large(user_pages);
478
479         return ret;
480 }
481
482 /**
483  * Reads data from the object referenced by handle.
484  *
485  * On error, the contents of *data are undefined.
486  */
487 int
488 i915_gem_pread_ioctl(struct drm_device *dev, void *data,
489                      struct drm_file *file)
490 {
491         struct drm_i915_gem_pread *args = data;
492         struct drm_i915_gem_object *obj;
493         int ret = 0;
494
495         if (args->size == 0)
496                 return 0;
497
498         if (!access_ok(VERIFY_WRITE,
499                        (char __user *)(uintptr_t)args->data_ptr,
500                        args->size))
501                 return -EFAULT;
502
503         ret = fault_in_pages_writeable((char __user *)(uintptr_t)args->data_ptr,
504                                        args->size);
505         if (ret)
506                 return -EFAULT;
507
508         ret = i915_mutex_lock_interruptible(dev);
509         if (ret)
510                 return ret;
511
512         obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
513         if (obj == NULL) {
514                 ret = -ENOENT;
515                 goto unlock;
516         }
517
518         /* Bounds check source.  */
519         if (args->offset > obj->base.size ||
520             args->size > obj->base.size - args->offset) {
521                 ret = -EINVAL;
522                 goto out;
523         }
524
525         ret = i915_gem_object_set_cpu_read_domain_range(obj,
526                                                         args->offset,
527                                                         args->size);
528         if (ret)
529                 goto out;
530
531         ret = -EFAULT;
532         if (!i915_gem_object_needs_bit17_swizzle(obj))
533                 ret = i915_gem_shmem_pread_fast(dev, obj, args, file);
534         if (ret == -EFAULT)
535                 ret = i915_gem_shmem_pread_slow(dev, obj, args, file);
536
537 out:
538         drm_gem_object_unreference(&obj->base);
539 unlock:
540         mutex_unlock(&dev->struct_mutex);
541         return ret;
542 }
543
544 /* This is the fast write path which cannot handle
545  * page faults in the source data
546  */
547
548 static inline int
549 fast_user_write(struct io_mapping *mapping,
550                 loff_t page_base, int page_offset,
551                 char __user *user_data,
552                 int length)
553 {
554         char *vaddr_atomic;
555         unsigned long unwritten;
556
557         vaddr_atomic = io_mapping_map_atomic_wc(mapping, page_base);
558         unwritten = __copy_from_user_inatomic_nocache(vaddr_atomic + page_offset,
559                                                       user_data, length);
560         io_mapping_unmap_atomic(vaddr_atomic);
561         return unwritten;
562 }
563
564 /* Here's the write path which can sleep for
565  * page faults
566  */
567
568 static inline void
569 slow_kernel_write(struct io_mapping *mapping,
570                   loff_t gtt_base, int gtt_offset,
571                   struct page *user_page, int user_offset,
572                   int length)
573 {
574         char __iomem *dst_vaddr;
575         char *src_vaddr;
576
577         dst_vaddr = io_mapping_map_wc(mapping, gtt_base);
578         src_vaddr = kmap(user_page);
579
580         memcpy_toio(dst_vaddr + gtt_offset,
581                     src_vaddr + user_offset,
582                     length);
583
584         kunmap(user_page);
585         io_mapping_unmap(dst_vaddr);
586 }
587
588 /**
589  * This is the fast pwrite path, where we copy the data directly from the
590  * user into the GTT, uncached.
591  */
592 static int
593 i915_gem_gtt_pwrite_fast(struct drm_device *dev,
594                          struct drm_i915_gem_object *obj,
595                          struct drm_i915_gem_pwrite *args,
596                          struct drm_file *file)
597 {
598         drm_i915_private_t *dev_priv = dev->dev_private;
599         ssize_t remain;
600         loff_t offset, page_base;
601         char __user *user_data;
602         int page_offset, page_length;
603
604         user_data = (char __user *) (uintptr_t) args->data_ptr;
605         remain = args->size;
606
607         offset = obj->gtt_offset + args->offset;
608
609         while (remain > 0) {
610                 /* Operation in this page
611                  *
612                  * page_base = page offset within aperture
613                  * page_offset = offset within page
614                  * page_length = bytes to copy for this page
615                  */
616                 page_base = (offset & ~(PAGE_SIZE-1));
617                 page_offset = offset & (PAGE_SIZE-1);
618                 page_length = remain;
619                 if ((page_offset + remain) > PAGE_SIZE)
620                         page_length = PAGE_SIZE - page_offset;
621
622                 /* If we get a fault while copying data, then (presumably) our
623                  * source page isn't available.  Return the error and we'll
624                  * retry in the slow path.
625                  */
626                 if (fast_user_write(dev_priv->mm.gtt_mapping, page_base,
627                                     page_offset, user_data, page_length))
628
629                         return -EFAULT;
630
631                 remain -= page_length;
632                 user_data += page_length;
633                 offset += page_length;
634         }
635
636         return 0;
637 }
638
639 /**
640  * This is the fallback GTT pwrite path, which uses get_user_pages to pin
641  * the memory and maps it using kmap_atomic for copying.
642  *
643  * This code resulted in x11perf -rgb10text consuming about 10% more CPU
644  * than using i915_gem_gtt_pwrite_fast on a G45 (32-bit).
645  */
646 static int
647 i915_gem_gtt_pwrite_slow(struct drm_device *dev,
648                          struct drm_i915_gem_object *obj,
649                          struct drm_i915_gem_pwrite *args,
650                          struct drm_file *file)
651 {
652         drm_i915_private_t *dev_priv = dev->dev_private;
653         ssize_t remain;
654         loff_t gtt_page_base, offset;
655         loff_t first_data_page, last_data_page, num_pages;
656         loff_t pinned_pages, i;
657         struct page **user_pages;
658         struct mm_struct *mm = current->mm;
659         int gtt_page_offset, data_page_offset, data_page_index, page_length;
660         int ret;
661         uint64_t data_ptr = args->data_ptr;
662
663         remain = args->size;
664
665         /* Pin the user pages containing the data.  We can't fault while
666          * holding the struct mutex, and all of the pwrite implementations
667          * want to hold it while dereferencing the user data.
668          */
669         first_data_page = data_ptr / PAGE_SIZE;
670         last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE;
671         num_pages = last_data_page - first_data_page + 1;
672
673         user_pages = drm_malloc_ab(num_pages, sizeof(struct page *));
674         if (user_pages == NULL)
675                 return -ENOMEM;
676
677         mutex_unlock(&dev->struct_mutex);
678         down_read(&mm->mmap_sem);
679         pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr,
680                                       num_pages, 0, 0, user_pages, NULL);
681         up_read(&mm->mmap_sem);
682         mutex_lock(&dev->struct_mutex);
683         if (pinned_pages < num_pages) {
684                 ret = -EFAULT;
685                 goto out_unpin_pages;
686         }
687
688         ret = i915_gem_object_set_to_gtt_domain(obj, true);
689         if (ret)
690                 goto out_unpin_pages;
691
692         ret = i915_gem_object_put_fence(obj);
693         if (ret)
694                 goto out_unpin_pages;
695
696         offset = obj->gtt_offset + args->offset;
697
698         while (remain > 0) {
699                 /* Operation in this page
700                  *
701                  * gtt_page_base = page offset within aperture
702                  * gtt_page_offset = offset within page in aperture
703                  * data_page_index = page number in get_user_pages return
704                  * data_page_offset = offset with data_page_index page.
705                  * page_length = bytes to copy for this page
706                  */
707                 gtt_page_base = offset & PAGE_MASK;
708                 gtt_page_offset = offset & ~PAGE_MASK;
709                 data_page_index = data_ptr / PAGE_SIZE - first_data_page;
710                 data_page_offset = data_ptr & ~PAGE_MASK;
711
712                 page_length = remain;
713                 if ((gtt_page_offset + page_length) > PAGE_SIZE)
714                         page_length = PAGE_SIZE - gtt_page_offset;
715                 if ((data_page_offset + page_length) > PAGE_SIZE)
716                         page_length = PAGE_SIZE - data_page_offset;
717
718                 slow_kernel_write(dev_priv->mm.gtt_mapping,
719                                   gtt_page_base, gtt_page_offset,
720                                   user_pages[data_page_index],
721                                   data_page_offset,
722                                   page_length);
723
724                 remain -= page_length;
725                 offset += page_length;
726                 data_ptr += page_length;
727         }
728
729 out_unpin_pages:
730         for (i = 0; i < pinned_pages; i++)
731                 page_cache_release(user_pages[i]);
732         drm_free_large(user_pages);
733
734         return ret;
735 }
736
737 /**
738  * This is the fast shmem pwrite path, which attempts to directly
739  * copy_from_user into the kmapped pages backing the object.
740  */
741 static int
742 i915_gem_shmem_pwrite_fast(struct drm_device *dev,
743                            struct drm_i915_gem_object *obj,
744                            struct drm_i915_gem_pwrite *args,
745                            struct drm_file *file)
746 {
747         struct address_space *mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping;
748         ssize_t remain;
749         loff_t offset;
750         char __user *user_data;
751         int page_offset, page_length;
752
753         user_data = (char __user *) (uintptr_t) args->data_ptr;
754         remain = args->size;
755
756         offset = args->offset;
757         obj->dirty = 1;
758
759         while (remain > 0) {
760                 struct page *page;
761                 char *vaddr;
762                 int ret;
763
764                 /* Operation in this page
765                  *
766                  * page_offset = offset within page
767                  * page_length = bytes to copy for this page
768                  */
769                 page_offset = offset & (PAGE_SIZE-1);
770                 page_length = remain;
771                 if ((page_offset + remain) > PAGE_SIZE)
772                         page_length = PAGE_SIZE - page_offset;
773
774                 page = read_cache_page_gfp(mapping, offset >> PAGE_SHIFT,
775                                            GFP_HIGHUSER | __GFP_RECLAIMABLE);
776                 if (IS_ERR(page))
777                         return PTR_ERR(page);
778
779                 vaddr = kmap_atomic(page, KM_USER0);
780                 ret = __copy_from_user_inatomic(vaddr + page_offset,
781                                                 user_data,
782                                                 page_length);
783                 kunmap_atomic(vaddr, KM_USER0);
784
785                 set_page_dirty(page);
786                 mark_page_accessed(page);
787                 page_cache_release(page);
788
789                 /* If we get a fault while copying data, then (presumably) our
790                  * source page isn't available.  Return the error and we'll
791                  * retry in the slow path.
792                  */
793                 if (ret)
794                         return -EFAULT;
795
796                 remain -= page_length;
797                 user_data += page_length;
798                 offset += page_length;
799         }
800
801         return 0;
802 }
803
804 /**
805  * This is the fallback shmem pwrite path, which uses get_user_pages to pin
806  * the memory and maps it using kmap_atomic for copying.
807  *
808  * This avoids taking mmap_sem for faulting on the user's address while the
809  * struct_mutex is held.
810  */
811 static int
812 i915_gem_shmem_pwrite_slow(struct drm_device *dev,
813                            struct drm_i915_gem_object *obj,
814                            struct drm_i915_gem_pwrite *args,
815                            struct drm_file *file)
816 {
817         struct address_space *mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping;
818         struct mm_struct *mm = current->mm;
819         struct page **user_pages;
820         ssize_t remain;
821         loff_t offset, pinned_pages, i;
822         loff_t first_data_page, last_data_page, num_pages;
823         int shmem_page_offset;
824         int data_page_index,  data_page_offset;
825         int page_length;
826         int ret;
827         uint64_t data_ptr = args->data_ptr;
828         int do_bit17_swizzling;
829
830         remain = args->size;
831
832         /* Pin the user pages containing the data.  We can't fault while
833          * holding the struct mutex, and all of the pwrite implementations
834          * want to hold it while dereferencing the user data.
835          */
836         first_data_page = data_ptr / PAGE_SIZE;
837         last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE;
838         num_pages = last_data_page - first_data_page + 1;
839
840         user_pages = drm_malloc_ab(num_pages, sizeof(struct page *));
841         if (user_pages == NULL)
842                 return -ENOMEM;
843
844         mutex_unlock(&dev->struct_mutex);
845         down_read(&mm->mmap_sem);
846         pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr,
847                                       num_pages, 0, 0, user_pages, NULL);
848         up_read(&mm->mmap_sem);
849         mutex_lock(&dev->struct_mutex);
850         if (pinned_pages < num_pages) {
851                 ret = -EFAULT;
852                 goto out;
853         }
854
855         ret = i915_gem_object_set_to_cpu_domain(obj, 1);
856         if (ret)
857                 goto out;
858
859         do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj);
860
861         offset = args->offset;
862         obj->dirty = 1;
863
864         while (remain > 0) {
865                 struct page *page;
866
867                 /* Operation in this page
868                  *
869                  * shmem_page_offset = offset within page in shmem file
870                  * data_page_index = page number in get_user_pages return
871                  * data_page_offset = offset with data_page_index page.
872                  * page_length = bytes to copy for this page
873                  */
874                 shmem_page_offset = offset & ~PAGE_MASK;
875                 data_page_index = data_ptr / PAGE_SIZE - first_data_page;
876                 data_page_offset = data_ptr & ~PAGE_MASK;
877
878                 page_length = remain;
879                 if ((shmem_page_offset + page_length) > PAGE_SIZE)
880                         page_length = PAGE_SIZE - shmem_page_offset;
881                 if ((data_page_offset + page_length) > PAGE_SIZE)
882                         page_length = PAGE_SIZE - data_page_offset;
883
884                 page = read_cache_page_gfp(mapping, offset >> PAGE_SHIFT,
885                                            GFP_HIGHUSER | __GFP_RECLAIMABLE);
886                 if (IS_ERR(page)) {
887                         ret = PTR_ERR(page);
888                         goto out;
889                 }
890
891                 if (do_bit17_swizzling) {
892                         slow_shmem_bit17_copy(page,
893                                               shmem_page_offset,
894                                               user_pages[data_page_index],
895                                               data_page_offset,
896                                               page_length,
897                                               0);
898                 } else {
899                         slow_shmem_copy(page,
900                                         shmem_page_offset,
901                                         user_pages[data_page_index],
902                                         data_page_offset,
903                                         page_length);
904                 }
905
906                 set_page_dirty(page);
907                 mark_page_accessed(page);
908                 page_cache_release(page);
909
910                 remain -= page_length;
911                 data_ptr += page_length;
912                 offset += page_length;
913         }
914
915 out:
916         for (i = 0; i < pinned_pages; i++)
917                 page_cache_release(user_pages[i]);
918         drm_free_large(user_pages);
919
920         return ret;
921 }
922
923 /**
924  * Writes data to the object referenced by handle.
925  *
926  * On error, the contents of the buffer that were to be modified are undefined.
927  */
928 int
929 i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
930                       struct drm_file *file)
931 {
932         struct drm_i915_gem_pwrite *args = data;
933         struct drm_i915_gem_object *obj;
934         int ret;
935
936         if (args->size == 0)
937                 return 0;
938
939         if (!access_ok(VERIFY_READ,
940                        (char __user *)(uintptr_t)args->data_ptr,
941                        args->size))
942                 return -EFAULT;
943
944         ret = fault_in_pages_readable((char __user *)(uintptr_t)args->data_ptr,
945                                       args->size);
946         if (ret)
947                 return -EFAULT;
948
949         ret = i915_mutex_lock_interruptible(dev);
950         if (ret)
951                 return ret;
952
953         obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
954         if (obj == NULL) {
955                 ret = -ENOENT;
956                 goto unlock;
957         }
958
959         /* Bounds check destination. */
960         if (args->offset > obj->base.size ||
961             args->size > obj->base.size - args->offset) {
962                 ret = -EINVAL;
963                 goto out;
964         }
965
966         /* We can only do the GTT pwrite on untiled buffers, as otherwise
967          * it would end up going through the fenced access, and we'll get
968          * different detiling behavior between reading and writing.
969          * pread/pwrite currently are reading and writing from the CPU
970          * perspective, requiring manual detiling by the client.
971          */
972         if (obj->phys_obj)
973                 ret = i915_gem_phys_pwrite(dev, obj, args, file);
974         else if (obj->gtt_space &&
975                  obj->base.write_domain != I915_GEM_DOMAIN_CPU) {
976                 ret = i915_gem_object_pin(obj, 0, true);
977                 if (ret)
978                         goto out;
979
980                 ret = i915_gem_object_set_to_gtt_domain(obj, true);
981                 if (ret)
982                         goto out_unpin;
983
984                 ret = i915_gem_object_put_fence(obj);
985                 if (ret)
986                         goto out_unpin;
987
988                 ret = i915_gem_gtt_pwrite_fast(dev, obj, args, file);
989                 if (ret == -EFAULT)
990                         ret = i915_gem_gtt_pwrite_slow(dev, obj, args, file);
991
992 out_unpin:
993                 i915_gem_object_unpin(obj);
994         } else {
995                 ret = i915_gem_object_set_to_cpu_domain(obj, 1);
996                 if (ret)
997                         goto out;
998
999                 ret = -EFAULT;
1000                 if (!i915_gem_object_needs_bit17_swizzle(obj))
1001                         ret = i915_gem_shmem_pwrite_fast(dev, obj, args, file);
1002                 if (ret == -EFAULT)
1003                         ret = i915_gem_shmem_pwrite_slow(dev, obj, args, file);
1004         }
1005
1006 out:
1007         drm_gem_object_unreference(&obj->base);
1008 unlock:
1009         mutex_unlock(&dev->struct_mutex);
1010         return ret;
1011 }
1012
1013 /**
1014  * Called when user space prepares to use an object with the CPU, either
1015  * through the mmap ioctl's mapping or a GTT mapping.
1016  */
1017 int
1018 i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
1019                           struct drm_file *file)
1020 {
1021         struct drm_i915_gem_set_domain *args = data;
1022         struct drm_i915_gem_object *obj;
1023         uint32_t read_domains = args->read_domains;
1024         uint32_t write_domain = args->write_domain;
1025         int ret;
1026
1027         if (!(dev->driver->driver_features & DRIVER_GEM))
1028                 return -ENODEV;
1029
1030         /* Only handle setting domains to types used by the CPU. */
1031         if (write_domain & I915_GEM_GPU_DOMAINS)
1032                 return -EINVAL;
1033
1034         if (read_domains & I915_GEM_GPU_DOMAINS)
1035                 return -EINVAL;
1036
1037         /* Having something in the write domain implies it's in the read
1038          * domain, and only that read domain.  Enforce that in the request.
1039          */
1040         if (write_domain != 0 && read_domains != write_domain)
1041                 return -EINVAL;
1042
1043         ret = i915_mutex_lock_interruptible(dev);
1044         if (ret)
1045                 return ret;
1046
1047         obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
1048         if (obj == NULL) {
1049                 ret = -ENOENT;
1050                 goto unlock;
1051         }
1052
1053         if (read_domains & I915_GEM_DOMAIN_GTT) {
1054                 ret = i915_gem_object_set_to_gtt_domain(obj, write_domain != 0);
1055
1056                 /* Silently promote "you're not bound, there was nothing to do"
1057                  * to success, since the client was just asking us to
1058                  * make sure everything was done.
1059                  */
1060                 if (ret == -EINVAL)
1061                         ret = 0;
1062         } else {
1063                 ret = i915_gem_object_set_to_cpu_domain(obj, write_domain != 0);
1064         }
1065
1066         drm_gem_object_unreference(&obj->base);
1067 unlock:
1068         mutex_unlock(&dev->struct_mutex);
1069         return ret;
1070 }
1071
1072 /**
1073  * Called when user space has done writes to this buffer
1074  */
1075 int
1076 i915_gem_sw_finish_ioctl(struct drm_device *dev, void *data,
1077                          struct drm_file *file)
1078 {
1079         struct drm_i915_gem_sw_finish *args = data;
1080         struct drm_i915_gem_object *obj;
1081         int ret = 0;
1082
1083         if (!(dev->driver->driver_features & DRIVER_GEM))
1084                 return -ENODEV;
1085
1086         ret = i915_mutex_lock_interruptible(dev);
1087         if (ret)
1088                 return ret;
1089
1090         obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
1091         if (obj == NULL) {
1092                 ret = -ENOENT;
1093                 goto unlock;
1094         }
1095
1096         /* Pinned buffers may be scanout, so flush the cache */
1097         if (obj->pin_count)
1098                 i915_gem_object_flush_cpu_write_domain(obj);
1099
1100         drm_gem_object_unreference(&obj->base);
1101 unlock:
1102         mutex_unlock(&dev->struct_mutex);
1103         return ret;
1104 }
1105
1106 /**
1107  * Maps the contents of an object, returning the address it is mapped
1108  * into.
1109  *
1110  * While the mapping holds a reference on the contents of the object, it doesn't
1111  * imply a ref on the object itself.
1112  */
1113 int
1114 i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
1115                     struct drm_file *file)
1116 {
1117         struct drm_i915_private *dev_priv = dev->dev_private;
1118         struct drm_i915_gem_mmap *args = data;
1119         struct drm_gem_object *obj;
1120         loff_t offset;
1121         unsigned long addr;
1122
1123         if (!(dev->driver->driver_features & DRIVER_GEM))
1124                 return -ENODEV;
1125
1126         obj = drm_gem_object_lookup(dev, file, args->handle);
1127         if (obj == NULL)
1128                 return -ENOENT;
1129
1130         if (obj->size > dev_priv->mm.gtt_mappable_end) {
1131                 drm_gem_object_unreference_unlocked(obj);
1132                 return -E2BIG;
1133         }
1134
1135         offset = args->offset;
1136
1137         down_write(&current->mm->mmap_sem);
1138         addr = do_mmap(obj->filp, 0, args->size,
1139                        PROT_READ | PROT_WRITE, MAP_SHARED,
1140                        args->offset);
1141         up_write(&current->mm->mmap_sem);
1142         drm_gem_object_unreference_unlocked(obj);
1143         if (IS_ERR((void *)addr))
1144                 return addr;
1145
1146         args->addr_ptr = (uint64_t) addr;
1147
1148         return 0;
1149 }
1150
1151 /**
1152  * i915_gem_fault - fault a page into the GTT
1153  * vma: VMA in question
1154  * vmf: fault info
1155  *
1156  * The fault handler is set up by drm_gem_mmap() when a object is GTT mapped
1157  * from userspace.  The fault handler takes care of binding the object to
1158  * the GTT (if needed), allocating and programming a fence register (again,
1159  * only if needed based on whether the old reg is still valid or the object
1160  * is tiled) and inserting a new PTE into the faulting process.
1161  *
1162  * Note that the faulting process may involve evicting existing objects
1163  * from the GTT and/or fence registers to make room.  So performance may
1164  * suffer if the GTT working set is large or there are few fence registers
1165  * left.
1166  */
1167 int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1168 {
1169         struct drm_i915_gem_object *obj = to_intel_bo(vma->vm_private_data);
1170         struct drm_device *dev = obj->base.dev;
1171         drm_i915_private_t *dev_priv = dev->dev_private;
1172         pgoff_t page_offset;
1173         unsigned long pfn;
1174         int ret = 0;
1175         bool write = !!(vmf->flags & FAULT_FLAG_WRITE);
1176
1177         /* We don't use vmf->pgoff since that has the fake offset */
1178         page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
1179                 PAGE_SHIFT;
1180
1181         /* Now bind it into the GTT if needed */
1182         mutex_lock(&dev->struct_mutex);
1183
1184         if (!obj->map_and_fenceable) {
1185                 ret = i915_gem_object_unbind(obj);
1186                 if (ret)
1187                         goto unlock;
1188         }
1189         if (!obj->gtt_space) {
1190                 ret = i915_gem_object_bind_to_gtt(obj, 0, true);
1191                 if (ret)
1192                         goto unlock;
1193         }
1194
1195         ret = i915_gem_object_set_to_gtt_domain(obj, write);
1196         if (ret)
1197                 goto unlock;
1198
1199         if (obj->tiling_mode == I915_TILING_NONE)
1200                 ret = i915_gem_object_put_fence(obj);
1201         else
1202                 ret = i915_gem_object_get_fence(obj, NULL, true);
1203         if (ret)
1204                 goto unlock;
1205
1206         if (i915_gem_object_is_inactive(obj))
1207                 list_move_tail(&obj->mm_list, &dev_priv->mm.inactive_list);
1208
1209         obj->fault_mappable = true;
1210
1211         pfn = ((dev->agp->base + obj->gtt_offset) >> PAGE_SHIFT) +
1212                 page_offset;
1213
1214         /* Finally, remap it using the new GTT offset */
1215         ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn);
1216 unlock:
1217         mutex_unlock(&dev->struct_mutex);
1218
1219         switch (ret) {
1220         case -EAGAIN:
1221                 set_need_resched();
1222         case 0:
1223         case -ERESTARTSYS:
1224                 return VM_FAULT_NOPAGE;
1225         case -ENOMEM:
1226                 return VM_FAULT_OOM;
1227         default:
1228                 return VM_FAULT_SIGBUS;
1229         }
1230 }
1231
1232 /**
1233  * i915_gem_create_mmap_offset - create a fake mmap offset for an object
1234  * @obj: obj in question
1235  *
1236  * GEM memory mapping works by handing back to userspace a fake mmap offset
1237  * it can use in a subsequent mmap(2) call.  The DRM core code then looks
1238  * up the object based on the offset and sets up the various memory mapping
1239  * structures.
1240  *
1241  * This routine allocates and attaches a fake offset for @obj.
1242  */
1243 static int
1244 i915_gem_create_mmap_offset(struct drm_i915_gem_object *obj)
1245 {
1246         struct drm_device *dev = obj->base.dev;
1247         struct drm_gem_mm *mm = dev->mm_private;
1248         struct drm_map_list *list;
1249         struct drm_local_map *map;
1250         int ret = 0;
1251
1252         /* Set the object up for mmap'ing */
1253         list = &obj->base.map_list;
1254         list->map = kzalloc(sizeof(struct drm_map_list), GFP_KERNEL);
1255         if (!list->map)
1256                 return -ENOMEM;
1257
1258         map = list->map;
1259         map->type = _DRM_GEM;
1260         map->size = obj->base.size;
1261         map->handle = obj;
1262
1263         /* Get a DRM GEM mmap offset allocated... */
1264         list->file_offset_node = drm_mm_search_free(&mm->offset_manager,
1265                                                     obj->base.size / PAGE_SIZE,
1266                                                     0, 0);
1267         if (!list->file_offset_node) {
1268                 DRM_ERROR("failed to allocate offset for bo %d\n",
1269                           obj->base.name);
1270                 ret = -ENOSPC;
1271                 goto out_free_list;
1272         }
1273
1274         list->file_offset_node = drm_mm_get_block(list->file_offset_node,
1275                                                   obj->base.size / PAGE_SIZE,
1276                                                   0);
1277         if (!list->file_offset_node) {
1278                 ret = -ENOMEM;
1279                 goto out_free_list;
1280         }
1281
1282         list->hash.key = list->file_offset_node->start;
1283         ret = drm_ht_insert_item(&mm->offset_hash, &list->hash);
1284         if (ret) {
1285                 DRM_ERROR("failed to add to map hash\n");
1286                 goto out_free_mm;
1287         }
1288
1289         return 0;
1290
1291 out_free_mm:
1292         drm_mm_put_block(list->file_offset_node);
1293 out_free_list:
1294         kfree(list->map);
1295         list->map = NULL;
1296
1297         return ret;
1298 }
1299
1300 /**
1301  * i915_gem_release_mmap - remove physical page mappings
1302  * @obj: obj in question
1303  *
1304  * Preserve the reservation of the mmapping with the DRM core code, but
1305  * relinquish ownership of the pages back to the system.
1306  *
1307  * It is vital that we remove the page mapping if we have mapped a tiled
1308  * object through the GTT and then lose the fence register due to
1309  * resource pressure. Similarly if the object has been moved out of the
1310  * aperture, than pages mapped into userspace must be revoked. Removing the
1311  * mapping will then trigger a page fault on the next user access, allowing
1312  * fixup by i915_gem_fault().
1313  */
1314 void
1315 i915_gem_release_mmap(struct drm_i915_gem_object *obj)
1316 {
1317         if (!obj->fault_mappable)
1318                 return;
1319
1320         unmap_mapping_range(obj->base.dev->dev_mapping,
1321                             (loff_t)obj->base.map_list.hash.key<<PAGE_SHIFT,
1322                             obj->base.size, 1);
1323
1324         obj->fault_mappable = false;
1325 }
1326
1327 static void
1328 i915_gem_free_mmap_offset(struct drm_i915_gem_object *obj)
1329 {
1330         struct drm_device *dev = obj->base.dev;
1331         struct drm_gem_mm *mm = dev->mm_private;
1332         struct drm_map_list *list = &obj->base.map_list;
1333
1334         drm_ht_remove_item(&mm->offset_hash, &list->hash);
1335         drm_mm_put_block(list->file_offset_node);
1336         kfree(list->map);
1337         list->map = NULL;
1338 }
1339
1340 static uint32_t
1341 i915_gem_get_gtt_size(struct drm_i915_gem_object *obj)
1342 {
1343         struct drm_device *dev = obj->base.dev;
1344         uint32_t size;
1345
1346         if (INTEL_INFO(dev)->gen >= 4 ||
1347             obj->tiling_mode == I915_TILING_NONE)
1348                 return obj->base.size;
1349
1350         /* Previous chips need a power-of-two fence region when tiling */
1351         if (INTEL_INFO(dev)->gen == 3)
1352                 size = 1024*1024;
1353         else
1354                 size = 512*1024;
1355
1356         while (size < obj->base.size)
1357                 size <<= 1;
1358
1359         return size;
1360 }
1361
1362 /**
1363  * i915_gem_get_gtt_alignment - return required GTT alignment for an object
1364  * @obj: object to check
1365  *
1366  * Return the required GTT alignment for an object, taking into account
1367  * potential fence register mapping.
1368  */
1369 static uint32_t
1370 i915_gem_get_gtt_alignment(struct drm_i915_gem_object *obj)
1371 {
1372         struct drm_device *dev = obj->base.dev;
1373
1374         /*
1375          * Minimum alignment is 4k (GTT page size), but might be greater
1376          * if a fence register is needed for the object.
1377          */
1378         if (INTEL_INFO(dev)->gen >= 4 ||
1379             obj->tiling_mode == I915_TILING_NONE)
1380                 return 4096;
1381
1382         /*
1383          * Previous chips need to be aligned to the size of the smallest
1384          * fence register that can contain the object.
1385          */
1386         return i915_gem_get_gtt_size(obj);
1387 }
1388
1389 /**
1390  * i915_gem_get_unfenced_gtt_alignment - return required GTT alignment for an
1391  *                                       unfenced object
1392  * @obj: object to check
1393  *
1394  * Return the required GTT alignment for an object, only taking into account
1395  * unfenced tiled surface requirements.
1396  */
1397 static uint32_t
1398 i915_gem_get_unfenced_gtt_alignment(struct drm_i915_gem_object *obj)
1399 {
1400         struct drm_device *dev = obj->base.dev;
1401         int tile_height;
1402
1403         /*
1404          * Minimum alignment is 4k (GTT page size) for sane hw.
1405          */
1406         if (INTEL_INFO(dev)->gen >= 4 || IS_G33(dev) ||
1407             obj->tiling_mode == I915_TILING_NONE)
1408                 return 4096;
1409
1410         /*
1411          * Older chips need unfenced tiled buffers to be aligned to the left
1412          * edge of an even tile row (where tile rows are counted as if the bo is
1413          * placed in a fenced gtt region).
1414          */
1415         if (IS_GEN2(dev) ||
1416             (obj->tiling_mode == I915_TILING_Y && HAS_128_BYTE_Y_TILING(dev)))
1417                 tile_height = 32;
1418         else
1419                 tile_height = 8;
1420
1421         return tile_height * obj->stride * 2;
1422 }
1423
1424 /**
1425  * i915_gem_mmap_gtt_ioctl - prepare an object for GTT mmap'ing
1426  * @dev: DRM device
1427  * @data: GTT mapping ioctl data
1428  * @file: GEM object info
1429  *
1430  * Simply returns the fake offset to userspace so it can mmap it.
1431  * The mmap call will end up in drm_gem_mmap(), which will set things
1432  * up so we can get faults in the handler above.
1433  *
1434  * The fault handler will take care of binding the object into the GTT
1435  * (since it may have been evicted to make room for something), allocating
1436  * a fence register, and mapping the appropriate aperture address into
1437  * userspace.
1438  */
1439 int
1440 i915_gem_mmap_gtt_ioctl(struct drm_device *dev, void *data,
1441                         struct drm_file *file)
1442 {
1443         struct drm_i915_private *dev_priv = dev->dev_private;
1444         struct drm_i915_gem_mmap_gtt *args = data;
1445         struct drm_i915_gem_object *obj;
1446         int ret;
1447
1448         if (!(dev->driver->driver_features & DRIVER_GEM))
1449                 return -ENODEV;
1450
1451         ret = i915_mutex_lock_interruptible(dev);
1452         if (ret)
1453                 return ret;
1454
1455         obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
1456         if (obj == NULL) {
1457                 ret = -ENOENT;
1458                 goto unlock;
1459         }
1460
1461         if (obj->base.size > dev_priv->mm.gtt_mappable_end) {
1462                 ret = -E2BIG;
1463                 goto unlock;
1464         }
1465
1466         if (obj->madv != I915_MADV_WILLNEED) {
1467                 DRM_ERROR("Attempting to mmap a purgeable buffer\n");
1468                 ret = -EINVAL;
1469                 goto out;
1470         }
1471
1472         if (!obj->base.map_list.map) {
1473                 ret = i915_gem_create_mmap_offset(obj);
1474                 if (ret)
1475                         goto out;
1476         }
1477
1478         args->offset = (u64)obj->base.map_list.hash.key << PAGE_SHIFT;
1479
1480 out:
1481         drm_gem_object_unreference(&obj->base);
1482 unlock:
1483         mutex_unlock(&dev->struct_mutex);
1484         return ret;
1485 }
1486
1487 static int
1488 i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj,
1489                               gfp_t gfpmask)
1490 {
1491         int page_count, i;
1492         struct address_space *mapping;
1493         struct inode *inode;
1494         struct page *page;
1495
1496         /* Get the list of pages out of our struct file.  They'll be pinned
1497          * at this point until we release them.
1498          */
1499         page_count = obj->base.size / PAGE_SIZE;
1500         BUG_ON(obj->pages != NULL);
1501         obj->pages = drm_malloc_ab(page_count, sizeof(struct page *));
1502         if (obj->pages == NULL)
1503                 return -ENOMEM;
1504
1505         inode = obj->base.filp->f_path.dentry->d_inode;
1506         mapping = inode->i_mapping;
1507         for (i = 0; i < page_count; i++) {
1508                 page = read_cache_page_gfp(mapping, i,
1509                                            GFP_HIGHUSER |
1510                                            __GFP_COLD |
1511                                            __GFP_RECLAIMABLE |
1512                                            gfpmask);
1513                 if (IS_ERR(page))
1514                         goto err_pages;
1515
1516                 obj->pages[i] = page;
1517         }
1518
1519         if (obj->tiling_mode != I915_TILING_NONE)
1520                 i915_gem_object_do_bit_17_swizzle(obj);
1521
1522         return 0;
1523
1524 err_pages:
1525         while (i--)
1526                 page_cache_release(obj->pages[i]);
1527
1528         drm_free_large(obj->pages);
1529         obj->pages = NULL;
1530         return PTR_ERR(page);
1531 }
1532
1533 static void
1534 i915_gem_object_put_pages_gtt(struct drm_i915_gem_object *obj)
1535 {
1536         int page_count = obj->base.size / PAGE_SIZE;
1537         int i;
1538
1539         BUG_ON(obj->madv == __I915_MADV_PURGED);
1540
1541         if (obj->tiling_mode != I915_TILING_NONE)
1542                 i915_gem_object_save_bit_17_swizzle(obj);
1543
1544         if (obj->madv == I915_MADV_DONTNEED)
1545                 obj->dirty = 0;
1546
1547         for (i = 0; i < page_count; i++) {
1548                 if (obj->dirty)
1549                         set_page_dirty(obj->pages[i]);
1550
1551                 if (obj->madv == I915_MADV_WILLNEED)
1552                         mark_page_accessed(obj->pages[i]);
1553
1554                 page_cache_release(obj->pages[i]);
1555         }
1556         obj->dirty = 0;
1557
1558         drm_free_large(obj->pages);
1559         obj->pages = NULL;
1560 }
1561
1562 void
1563 i915_gem_object_move_to_active(struct drm_i915_gem_object *obj,
1564                                struct intel_ring_buffer *ring,
1565                                u32 seqno)
1566 {
1567         struct drm_device *dev = obj->base.dev;
1568         struct drm_i915_private *dev_priv = dev->dev_private;
1569
1570         BUG_ON(ring == NULL);
1571         obj->ring = ring;
1572
1573         /* Add a reference if we're newly entering the active list. */
1574         if (!obj->active) {
1575                 drm_gem_object_reference(&obj->base);
1576                 obj->active = 1;
1577         }
1578
1579         /* Move from whatever list we were on to the tail of execution. */
1580         list_move_tail(&obj->mm_list, &dev_priv->mm.active_list);
1581         list_move_tail(&obj->ring_list, &ring->active_list);
1582
1583         obj->last_rendering_seqno = seqno;
1584         if (obj->fenced_gpu_access) {
1585                 struct drm_i915_fence_reg *reg;
1586
1587                 BUG_ON(obj->fence_reg == I915_FENCE_REG_NONE);
1588
1589                 obj->last_fenced_seqno = seqno;
1590                 obj->last_fenced_ring = ring;
1591
1592                 reg = &dev_priv->fence_regs[obj->fence_reg];
1593                 list_move_tail(&reg->lru_list, &dev_priv->mm.fence_list);
1594         }
1595 }
1596
1597 static void
1598 i915_gem_object_move_off_active(struct drm_i915_gem_object *obj)
1599 {
1600         list_del_init(&obj->ring_list);
1601         obj->last_rendering_seqno = 0;
1602 }
1603
1604 static void
1605 i915_gem_object_move_to_flushing(struct drm_i915_gem_object *obj)
1606 {
1607         struct drm_device *dev = obj->base.dev;
1608         drm_i915_private_t *dev_priv = dev->dev_private;
1609
1610         BUG_ON(!obj->active);
1611         list_move_tail(&obj->mm_list, &dev_priv->mm.flushing_list);
1612
1613         i915_gem_object_move_off_active(obj);
1614 }
1615
1616 static void
1617 i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj)
1618 {
1619         struct drm_device *dev = obj->base.dev;
1620         struct drm_i915_private *dev_priv = dev->dev_private;
1621
1622         if (obj->pin_count != 0)
1623                 list_move_tail(&obj->mm_list, &dev_priv->mm.pinned_list);
1624         else
1625                 list_move_tail(&obj->mm_list, &dev_priv->mm.inactive_list);
1626
1627         BUG_ON(!list_empty(&obj->gpu_write_list));
1628         BUG_ON(!obj->active);
1629         obj->ring = NULL;
1630
1631         i915_gem_object_move_off_active(obj);
1632         obj->fenced_gpu_access = false;
1633
1634         obj->active = 0;
1635         obj->pending_gpu_write = false;
1636         drm_gem_object_unreference(&obj->base);
1637
1638         WARN_ON(i915_verify_lists(dev));
1639 }
1640
1641 /* Immediately discard the backing storage */
1642 static void
1643 i915_gem_object_truncate(struct drm_i915_gem_object *obj)
1644 {
1645         struct inode *inode;
1646
1647         /* Our goal here is to return as much of the memory as
1648          * is possible back to the system as we are called from OOM.
1649          * To do this we must instruct the shmfs to drop all of its
1650          * backing pages, *now*. Here we mirror the actions taken
1651          * when by shmem_delete_inode() to release the backing store.
1652          */
1653         inode = obj->base.filp->f_path.dentry->d_inode;
1654         truncate_inode_pages(inode->i_mapping, 0);
1655         if (inode->i_op->truncate_range)
1656                 inode->i_op->truncate_range(inode, 0, (loff_t)-1);
1657
1658         obj->madv = __I915_MADV_PURGED;
1659 }
1660
1661 static inline int
1662 i915_gem_object_is_purgeable(struct drm_i915_gem_object *obj)
1663 {
1664         return obj->madv == I915_MADV_DONTNEED;
1665 }
1666
1667 static void
1668 i915_gem_process_flushing_list(struct drm_device *dev,
1669                                uint32_t flush_domains,
1670                                struct intel_ring_buffer *ring)
1671 {
1672         struct drm_i915_gem_object *obj, *next;
1673
1674         list_for_each_entry_safe(obj, next,
1675                                  &ring->gpu_write_list,
1676                                  gpu_write_list) {
1677                 if (obj->base.write_domain & flush_domains) {
1678                         uint32_t old_write_domain = obj->base.write_domain;
1679
1680                         obj->base.write_domain = 0;
1681                         list_del_init(&obj->gpu_write_list);
1682                         i915_gem_object_move_to_active(obj, ring,
1683                                                        i915_gem_next_request_seqno(dev, ring));
1684
1685                         trace_i915_gem_object_change_domain(obj,
1686                                                             obj->base.read_domains,
1687                                                             old_write_domain);
1688                 }
1689         }
1690 }
1691
1692 int
1693 i915_add_request(struct drm_device *dev,
1694                  struct drm_file *file,
1695                  struct drm_i915_gem_request *request,
1696                  struct intel_ring_buffer *ring)
1697 {
1698         drm_i915_private_t *dev_priv = dev->dev_private;
1699         struct drm_i915_file_private *file_priv = NULL;
1700         uint32_t seqno;
1701         int was_empty;
1702         int ret;
1703
1704         BUG_ON(request == NULL);
1705
1706         if (file != NULL)
1707                 file_priv = file->driver_priv;
1708
1709         ret = ring->add_request(ring, &seqno);
1710         if (ret)
1711             return ret;
1712
1713         ring->outstanding_lazy_request = false;
1714
1715         request->seqno = seqno;
1716         request->ring = ring;
1717         request->emitted_jiffies = jiffies;
1718         was_empty = list_empty(&ring->request_list);
1719         list_add_tail(&request->list, &ring->request_list);
1720
1721         if (file_priv) {
1722                 spin_lock(&file_priv->mm.lock);
1723                 request->file_priv = file_priv;
1724                 list_add_tail(&request->client_list,
1725                               &file_priv->mm.request_list);
1726                 spin_unlock(&file_priv->mm.lock);
1727         }
1728
1729         if (!dev_priv->mm.suspended) {
1730                 mod_timer(&dev_priv->hangcheck_timer,
1731                           jiffies + msecs_to_jiffies(DRM_I915_HANGCHECK_PERIOD));
1732                 if (was_empty)
1733                         queue_delayed_work(dev_priv->wq,
1734                                            &dev_priv->mm.retire_work, HZ);
1735         }
1736         return 0;
1737 }
1738
1739 static inline void
1740 i915_gem_request_remove_from_client(struct drm_i915_gem_request *request)
1741 {
1742         struct drm_i915_file_private *file_priv = request->file_priv;
1743
1744         if (!file_priv)
1745                 return;
1746
1747         spin_lock(&file_priv->mm.lock);
1748         list_del(&request->client_list);
1749         request->file_priv = NULL;
1750         spin_unlock(&file_priv->mm.lock);
1751 }
1752
1753 static void i915_gem_reset_ring_lists(struct drm_i915_private *dev_priv,
1754                                       struct intel_ring_buffer *ring)
1755 {
1756         while (!list_empty(&ring->request_list)) {
1757                 struct drm_i915_gem_request *request;
1758
1759                 request = list_first_entry(&ring->request_list,
1760                                            struct drm_i915_gem_request,
1761                                            list);
1762
1763                 list_del(&request->list);
1764                 i915_gem_request_remove_from_client(request);
1765                 kfree(request);
1766         }
1767
1768         while (!list_empty(&ring->active_list)) {
1769                 struct drm_i915_gem_object *obj;
1770
1771                 obj = list_first_entry(&ring->active_list,
1772                                        struct drm_i915_gem_object,
1773                                        ring_list);
1774
1775                 obj->base.write_domain = 0;
1776                 list_del_init(&obj->gpu_write_list);
1777                 i915_gem_object_move_to_inactive(obj);
1778         }
1779 }
1780
1781 static void i915_gem_reset_fences(struct drm_device *dev)
1782 {
1783         struct drm_i915_private *dev_priv = dev->dev_private;
1784         int i;
1785
1786         for (i = 0; i < 16; i++) {
1787                 struct drm_i915_fence_reg *reg = &dev_priv->fence_regs[i];
1788                 struct drm_i915_gem_object *obj = reg->obj;
1789
1790                 if (!obj)
1791                         continue;
1792
1793                 if (obj->tiling_mode)
1794                         i915_gem_release_mmap(obj);
1795
1796                 reg->obj->fence_reg = I915_FENCE_REG_NONE;
1797                 reg->obj->fenced_gpu_access = false;
1798                 reg->obj->last_fenced_seqno = 0;
1799                 reg->obj->last_fenced_ring = NULL;
1800                 i915_gem_clear_fence_reg(dev, reg);
1801         }
1802 }
1803
1804 void i915_gem_reset(struct drm_device *dev)
1805 {
1806         struct drm_i915_private *dev_priv = dev->dev_private;
1807         struct drm_i915_gem_object *obj;
1808         int i;
1809
1810         for (i = 0; i < I915_NUM_RINGS; i++)
1811                 i915_gem_reset_ring_lists(dev_priv, &dev_priv->ring[i]);
1812
1813         /* Remove anything from the flushing lists. The GPU cache is likely
1814          * to be lost on reset along with the data, so simply move the
1815          * lost bo to the inactive list.
1816          */
1817         while (!list_empty(&dev_priv->mm.flushing_list)) {
1818                 obj= list_first_entry(&dev_priv->mm.flushing_list,
1819                                       struct drm_i915_gem_object,
1820                                       mm_list);
1821
1822                 obj->base.write_domain = 0;
1823                 list_del_init(&obj->gpu_write_list);
1824                 i915_gem_object_move_to_inactive(obj);
1825         }
1826
1827         /* Move everything out of the GPU domains to ensure we do any
1828          * necessary invalidation upon reuse.
1829          */
1830         list_for_each_entry(obj,
1831                             &dev_priv->mm.inactive_list,
1832                             mm_list)
1833         {
1834                 obj->base.read_domains &= ~I915_GEM_GPU_DOMAINS;
1835         }
1836
1837         /* The fence registers are invalidated so clear them out */
1838         i915_gem_reset_fences(dev);
1839 }
1840
1841 /**
1842  * This function clears the request list as sequence numbers are passed.
1843  */
1844 static void
1845 i915_gem_retire_requests_ring(struct drm_device *dev,
1846                               struct intel_ring_buffer *ring)
1847 {
1848         drm_i915_private_t *dev_priv = dev->dev_private;
1849         uint32_t seqno;
1850         int i;
1851
1852         if (!ring->status_page.page_addr ||
1853             list_empty(&ring->request_list))
1854                 return;
1855
1856         WARN_ON(i915_verify_lists(dev));
1857
1858         seqno = ring->get_seqno(ring);
1859
1860         for (i = 0; i < I915_NUM_RINGS; i++)
1861                 if (seqno >= ring->sync_seqno[i])
1862                         ring->sync_seqno[i] = 0;
1863
1864         while (!list_empty(&ring->request_list)) {
1865                 struct drm_i915_gem_request *request;
1866
1867                 request = list_first_entry(&ring->request_list,
1868                                            struct drm_i915_gem_request,
1869                                            list);
1870
1871                 if (!i915_seqno_passed(seqno, request->seqno))
1872                         break;
1873
1874                 trace_i915_gem_request_retire(dev, request->seqno);
1875
1876                 list_del(&request->list);
1877                 i915_gem_request_remove_from_client(request);
1878                 kfree(request);
1879         }
1880
1881         /* Move any buffers on the active list that are no longer referenced
1882          * by the ringbuffer to the flushing/inactive lists as appropriate.
1883          */
1884         while (!list_empty(&ring->active_list)) {
1885                 struct drm_i915_gem_object *obj;
1886
1887                 obj= list_first_entry(&ring->active_list,
1888                                       struct drm_i915_gem_object,
1889                                       ring_list);
1890
1891                 if (!i915_seqno_passed(seqno, obj->last_rendering_seqno))
1892                         break;
1893
1894                 if (obj->base.write_domain != 0)
1895                         i915_gem_object_move_to_flushing(obj);
1896                 else
1897                         i915_gem_object_move_to_inactive(obj);
1898         }
1899
1900         if (unlikely (dev_priv->trace_irq_seqno &&
1901                       i915_seqno_passed(dev_priv->trace_irq_seqno, seqno))) {
1902                 ring->irq_put(ring);
1903                 dev_priv->trace_irq_seqno = 0;
1904         }
1905
1906         WARN_ON(i915_verify_lists(dev));
1907 }
1908
1909 void
1910 i915_gem_retire_requests(struct drm_device *dev)
1911 {
1912         drm_i915_private_t *dev_priv = dev->dev_private;
1913         int i;
1914
1915         if (!list_empty(&dev_priv->mm.deferred_free_list)) {
1916             struct drm_i915_gem_object *obj, *next;
1917
1918             /* We must be careful that during unbind() we do not
1919              * accidentally infinitely recurse into retire requests.
1920              * Currently:
1921              *   retire -> free -> unbind -> wait -> retire_ring
1922              */
1923             list_for_each_entry_safe(obj, next,
1924                                      &dev_priv->mm.deferred_free_list,
1925                                      mm_list)
1926                     i915_gem_free_object_tail(obj);
1927         }
1928
1929         for (i = 0; i < I915_NUM_RINGS; i++)
1930                 i915_gem_retire_requests_ring(dev, &dev_priv->ring[i]);
1931 }
1932
1933 static void
1934 i915_gem_retire_work_handler(struct work_struct *work)
1935 {
1936         drm_i915_private_t *dev_priv;
1937         struct drm_device *dev;
1938         bool idle;
1939         int i;
1940
1941         dev_priv = container_of(work, drm_i915_private_t,
1942                                 mm.retire_work.work);
1943         dev = dev_priv->dev;
1944
1945         /* Come back later if the device is busy... */
1946         if (!mutex_trylock(&dev->struct_mutex)) {
1947                 queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, HZ);
1948                 return;
1949         }
1950
1951         i915_gem_retire_requests(dev);
1952
1953         /* Send a periodic flush down the ring so we don't hold onto GEM
1954          * objects indefinitely.
1955          */
1956         idle = true;
1957         for (i = 0; i < I915_NUM_RINGS; i++) {
1958                 struct intel_ring_buffer *ring = &dev_priv->ring[i];
1959
1960                 if (!list_empty(&ring->gpu_write_list)) {
1961                         struct drm_i915_gem_request *request;
1962                         int ret;
1963
1964                         ret = i915_gem_flush_ring(dev, ring, 0,
1965                                                   I915_GEM_GPU_DOMAINS);
1966                         request = kzalloc(sizeof(*request), GFP_KERNEL);
1967                         if (ret || request == NULL ||
1968                             i915_add_request(dev, NULL, request, ring))
1969                             kfree(request);
1970                 }
1971
1972                 idle &= list_empty(&ring->request_list);
1973         }
1974
1975         if (!dev_priv->mm.suspended && !idle)
1976                 queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, HZ);
1977
1978         mutex_unlock(&dev->struct_mutex);
1979 }
1980
1981 int
1982 i915_do_wait_request(struct drm_device *dev, uint32_t seqno,
1983                      bool interruptible, struct intel_ring_buffer *ring)
1984 {
1985         drm_i915_private_t *dev_priv = dev->dev_private;
1986         u32 ier;
1987         int ret = 0;
1988
1989         BUG_ON(seqno == 0);
1990
1991         if (atomic_read(&dev_priv->mm.wedged))
1992                 return -EAGAIN;
1993
1994         if (seqno == ring->outstanding_lazy_request) {
1995                 struct drm_i915_gem_request *request;
1996
1997                 request = kzalloc(sizeof(*request), GFP_KERNEL);
1998                 if (request == NULL)
1999                         return -ENOMEM;
2000
2001                 ret = i915_add_request(dev, NULL, request, ring);
2002                 if (ret) {
2003                         kfree(request);
2004                         return ret;
2005                 }
2006
2007                 seqno = request->seqno;
2008         }
2009
2010         if (!i915_seqno_passed(ring->get_seqno(ring), seqno)) {
2011                 if (HAS_PCH_SPLIT(dev))
2012                         ier = I915_READ(DEIER) | I915_READ(GTIER);
2013                 else
2014                         ier = I915_READ(IER);
2015                 if (!ier) {
2016                         DRM_ERROR("something (likely vbetool) disabled "
2017                                   "interrupts, re-enabling\n");
2018                         i915_driver_irq_preinstall(dev);
2019                         i915_driver_irq_postinstall(dev);
2020                 }
2021
2022                 trace_i915_gem_request_wait_begin(dev, seqno);
2023
2024                 ring->waiting_seqno = seqno;
2025                 if (ring->irq_get(ring)) {
2026                         if (interruptible)
2027                                 ret = wait_event_interruptible(ring->irq_queue,
2028                                                                i915_seqno_passed(ring->get_seqno(ring), seqno)
2029                                                                || atomic_read(&dev_priv->mm.wedged));
2030                         else
2031                                 wait_event(ring->irq_queue,
2032                                            i915_seqno_passed(ring->get_seqno(ring), seqno)
2033                                            || atomic_read(&dev_priv->mm.wedged));
2034
2035                         ring->irq_put(ring);
2036                 } else if (wait_for(i915_seqno_passed(ring->get_seqno(ring),
2037                                                       seqno) ||
2038                                     atomic_read(&dev_priv->mm.wedged), 3000))
2039                         ret = -EBUSY;
2040                 ring->waiting_seqno = 0;
2041
2042                 trace_i915_gem_request_wait_end(dev, seqno);
2043         }
2044         if (atomic_read(&dev_priv->mm.wedged))
2045                 ret = -EAGAIN;
2046
2047         if (ret && ret != -ERESTARTSYS)
2048                 DRM_ERROR("%s returns %d (awaiting %d at %d, next %d)\n",
2049                           __func__, ret, seqno, ring->get_seqno(ring),
2050                           dev_priv->next_seqno);
2051
2052         /* Directly dispatch request retiring.  While we have the work queue
2053          * to handle this, the waiter on a request often wants an associated
2054          * buffer to have made it to the inactive list, and we would need
2055          * a separate wait queue to handle that.
2056          */
2057         if (ret == 0)
2058                 i915_gem_retire_requests_ring(dev, ring);
2059
2060         return ret;
2061 }
2062
2063 /**
2064  * Waits for a sequence number to be signaled, and cleans up the
2065  * request and object lists appropriately for that event.
2066  */
2067 static int
2068 i915_wait_request(struct drm_device *dev, uint32_t seqno,
2069                   struct intel_ring_buffer *ring)
2070 {
2071         return i915_do_wait_request(dev, seqno, 1, ring);
2072 }
2073
2074 /**
2075  * Ensures that all rendering to the object has completed and the object is
2076  * safe to unbind from the GTT or access from the CPU.
2077  */
2078 int
2079 i915_gem_object_wait_rendering(struct drm_i915_gem_object *obj,
2080                                bool interruptible)
2081 {
2082         struct drm_device *dev = obj->base.dev;
2083         int ret;
2084
2085         /* This function only exists to support waiting for existing rendering,
2086          * not for emitting required flushes.
2087          */
2088         BUG_ON((obj->base.write_domain & I915_GEM_GPU_DOMAINS) != 0);
2089
2090         /* If there is rendering queued on the buffer being evicted, wait for
2091          * it.
2092          */
2093         if (obj->active) {
2094                 ret = i915_do_wait_request(dev,
2095                                            obj->last_rendering_seqno,
2096                                            interruptible,
2097                                            obj->ring);
2098                 if (ret)
2099                         return ret;
2100         }
2101
2102         return 0;
2103 }
2104
2105 /**
2106  * Unbinds an object from the GTT aperture.
2107  */
2108 int
2109 i915_gem_object_unbind(struct drm_i915_gem_object *obj)
2110 {
2111         int ret = 0;
2112
2113         if (obj->gtt_space == NULL)
2114                 return 0;
2115
2116         if (obj->pin_count != 0) {
2117                 DRM_ERROR("Attempting to unbind pinned buffer\n");
2118                 return -EINVAL;
2119         }
2120
2121         /* blow away mappings if mapped through GTT */
2122         i915_gem_release_mmap(obj);
2123
2124         /* Move the object to the CPU domain to ensure that
2125          * any possible CPU writes while it's not in the GTT
2126          * are flushed when we go to remap it. This will
2127          * also ensure that all pending GPU writes are finished
2128          * before we unbind.
2129          */
2130         ret = i915_gem_object_set_to_cpu_domain(obj, 1);
2131         if (ret == -ERESTARTSYS)
2132                 return ret;
2133         /* Continue on if we fail due to EIO, the GPU is hung so we
2134          * should be safe and we need to cleanup or else we might
2135          * cause memory corruption through use-after-free.
2136          */
2137         if (ret) {
2138                 i915_gem_clflush_object(obj);
2139                 obj->base.read_domains = obj->base.write_domain = I915_GEM_DOMAIN_CPU;
2140         }
2141
2142         /* release the fence reg _after_ flushing */
2143         ret = i915_gem_object_put_fence(obj);
2144         if (ret == -ERESTARTSYS)
2145                 return ret;
2146
2147         i915_gem_gtt_unbind_object(obj);
2148         i915_gem_object_put_pages_gtt(obj);
2149
2150         list_del_init(&obj->gtt_list);
2151         list_del_init(&obj->mm_list);
2152         /* Avoid an unnecessary call to unbind on rebind. */
2153         obj->map_and_fenceable = true;
2154
2155         drm_mm_put_block(obj->gtt_space);
2156         obj->gtt_space = NULL;
2157         obj->gtt_offset = 0;
2158
2159         if (i915_gem_object_is_purgeable(obj))
2160                 i915_gem_object_truncate(obj);
2161
2162         trace_i915_gem_object_unbind(obj);
2163
2164         return ret;
2165 }
2166
2167 int
2168 i915_gem_flush_ring(struct drm_device *dev,
2169                     struct intel_ring_buffer *ring,
2170                     uint32_t invalidate_domains,
2171                     uint32_t flush_domains)
2172 {
2173         int ret;
2174
2175         ret = ring->flush(ring, invalidate_domains, flush_domains);
2176         if (ret)
2177                 return ret;
2178
2179         i915_gem_process_flushing_list(dev, flush_domains, ring);
2180         return 0;
2181 }
2182
2183 static int i915_ring_idle(struct drm_device *dev,
2184                           struct intel_ring_buffer *ring)
2185 {
2186         int ret;
2187
2188         if (list_empty(&ring->gpu_write_list) && list_empty(&ring->active_list))
2189                 return 0;
2190
2191         if (!list_empty(&ring->gpu_write_list)) {
2192                 ret = i915_gem_flush_ring(dev, ring,
2193                                     I915_GEM_GPU_DOMAINS, I915_GEM_GPU_DOMAINS);
2194                 if (ret)
2195                         return ret;
2196         }
2197
2198         return i915_wait_request(dev,
2199                                  i915_gem_next_request_seqno(dev, ring),
2200                                  ring);
2201 }
2202
2203 int
2204 i915_gpu_idle(struct drm_device *dev)
2205 {
2206         drm_i915_private_t *dev_priv = dev->dev_private;
2207         bool lists_empty;
2208         int ret, i;
2209
2210         lists_empty = (list_empty(&dev_priv->mm.flushing_list) &&
2211                        list_empty(&dev_priv->mm.active_list));
2212         if (lists_empty)
2213                 return 0;
2214
2215         /* Flush everything onto the inactive list. */
2216         for (i = 0; i < I915_NUM_RINGS; i++) {
2217                 ret = i915_ring_idle(dev, &dev_priv->ring[i]);
2218                 if (ret)
2219                         return ret;
2220         }
2221
2222         return 0;
2223 }
2224
2225 static int sandybridge_write_fence_reg(struct drm_i915_gem_object *obj,
2226                                        struct intel_ring_buffer *pipelined)
2227 {
2228         struct drm_device *dev = obj->base.dev;
2229         drm_i915_private_t *dev_priv = dev->dev_private;
2230         u32 size = obj->gtt_space->size;
2231         int regnum = obj->fence_reg;
2232         uint64_t val;
2233
2234         val = (uint64_t)((obj->gtt_offset + size - 4096) &
2235                          0xfffff000) << 32;
2236         val |= obj->gtt_offset & 0xfffff000;
2237         val |= (uint64_t)((obj->stride / 128) - 1) <<
2238                 SANDYBRIDGE_FENCE_PITCH_SHIFT;
2239
2240         if (obj->tiling_mode == I915_TILING_Y)
2241                 val |= 1 << I965_FENCE_TILING_Y_SHIFT;
2242         val |= I965_FENCE_REG_VALID;
2243
2244         if (pipelined) {
2245                 int ret = intel_ring_begin(pipelined, 6);
2246                 if (ret)
2247                         return ret;
2248
2249                 intel_ring_emit(pipelined, MI_NOOP);
2250                 intel_ring_emit(pipelined, MI_LOAD_REGISTER_IMM(2));
2251                 intel_ring_emit(pipelined, FENCE_REG_SANDYBRIDGE_0 + regnum*8);
2252                 intel_ring_emit(pipelined, (u32)val);
2253                 intel_ring_emit(pipelined, FENCE_REG_SANDYBRIDGE_0 + regnum*8 + 4);
2254                 intel_ring_emit(pipelined, (u32)(val >> 32));
2255                 intel_ring_advance(pipelined);
2256         } else
2257                 I915_WRITE64(FENCE_REG_SANDYBRIDGE_0 + regnum * 8, val);
2258
2259         return 0;
2260 }
2261
2262 static int i965_write_fence_reg(struct drm_i915_gem_object *obj,
2263                                 struct intel_ring_buffer *pipelined)
2264 {
2265         struct drm_device *dev = obj->base.dev;
2266         drm_i915_private_t *dev_priv = dev->dev_private;
2267         u32 size = obj->gtt_space->size;
2268         int regnum = obj->fence_reg;
2269         uint64_t val;
2270
2271         val = (uint64_t)((obj->gtt_offset + size - 4096) &
2272                     0xfffff000) << 32;
2273         val |= obj->gtt_offset & 0xfffff000;
2274         val |= ((obj->stride / 128) - 1) << I965_FENCE_PITCH_SHIFT;
2275         if (obj->tiling_mode == I915_TILING_Y)
2276                 val |= 1 << I965_FENCE_TILING_Y_SHIFT;
2277         val |= I965_FENCE_REG_VALID;
2278
2279         if (pipelined) {
2280                 int ret = intel_ring_begin(pipelined, 6);
2281                 if (ret)
2282                         return ret;
2283
2284                 intel_ring_emit(pipelined, MI_NOOP);
2285                 intel_ring_emit(pipelined, MI_LOAD_REGISTER_IMM(2));
2286                 intel_ring_emit(pipelined, FENCE_REG_965_0 + regnum*8);
2287                 intel_ring_emit(pipelined, (u32)val);
2288                 intel_ring_emit(pipelined, FENCE_REG_965_0 + regnum*8 + 4);
2289                 intel_ring_emit(pipelined, (u32)(val >> 32));
2290                 intel_ring_advance(pipelined);
2291         } else
2292                 I915_WRITE64(FENCE_REG_965_0 + regnum * 8, val);
2293
2294         return 0;
2295 }
2296
2297 static int i915_write_fence_reg(struct drm_i915_gem_object *obj,
2298                                 struct intel_ring_buffer *pipelined)
2299 {
2300         struct drm_device *dev = obj->base.dev;
2301         drm_i915_private_t *dev_priv = dev->dev_private;
2302         u32 size = obj->gtt_space->size;
2303         u32 fence_reg, val, pitch_val;
2304         int tile_width;
2305
2306         if (WARN((obj->gtt_offset & ~I915_FENCE_START_MASK) ||
2307                  (size & -size) != size ||
2308                  (obj->gtt_offset & (size - 1)),
2309                  "object 0x%08x [fenceable? %d] not 1M or pot-size (0x%08x) aligned\n",
2310                  obj->gtt_offset, obj->map_and_fenceable, size))
2311                 return -EINVAL;
2312
2313         if (obj->tiling_mode == I915_TILING_Y && HAS_128_BYTE_Y_TILING(dev))
2314                 tile_width = 128;
2315         else
2316                 tile_width = 512;
2317
2318         /* Note: pitch better be a power of two tile widths */
2319         pitch_val = obj->stride / tile_width;
2320         pitch_val = ffs(pitch_val) - 1;
2321
2322         val = obj->gtt_offset;
2323         if (obj->tiling_mode == I915_TILING_Y)
2324                 val |= 1 << I830_FENCE_TILING_Y_SHIFT;
2325         val |= I915_FENCE_SIZE_BITS(size);
2326         val |= pitch_val << I830_FENCE_PITCH_SHIFT;
2327         val |= I830_FENCE_REG_VALID;
2328
2329         fence_reg = obj->fence_reg;
2330         if (fence_reg < 8)
2331                 fence_reg = FENCE_REG_830_0 + fence_reg * 4;
2332         else
2333                 fence_reg = FENCE_REG_945_8 + (fence_reg - 8) * 4;
2334
2335         if (pipelined) {
2336                 int ret = intel_ring_begin(pipelined, 4);
2337                 if (ret)
2338                         return ret;
2339
2340                 intel_ring_emit(pipelined, MI_NOOP);
2341                 intel_ring_emit(pipelined, MI_LOAD_REGISTER_IMM(1));
2342                 intel_ring_emit(pipelined, fence_reg);
2343                 intel_ring_emit(pipelined, val);
2344                 intel_ring_advance(pipelined);
2345         } else
2346                 I915_WRITE(fence_reg, val);
2347
2348         return 0;
2349 }
2350
2351 static int i830_write_fence_reg(struct drm_i915_gem_object *obj,
2352                                 struct intel_ring_buffer *pipelined)
2353 {
2354         struct drm_device *dev = obj->base.dev;
2355         drm_i915_private_t *dev_priv = dev->dev_private;
2356         u32 size = obj->gtt_space->size;
2357         int regnum = obj->fence_reg;
2358         uint32_t val;
2359         uint32_t pitch_val;
2360
2361         if (WARN((obj->gtt_offset & ~I830_FENCE_START_MASK) ||
2362                  (size & -size) != size ||
2363                  (obj->gtt_offset & (size - 1)),
2364                  "object 0x%08x not 512K or pot-size 0x%08x aligned\n",
2365                  obj->gtt_offset, size))
2366                 return -EINVAL;
2367
2368         pitch_val = obj->stride / 128;
2369         pitch_val = ffs(pitch_val) - 1;
2370
2371         val = obj->gtt_offset;
2372         if (obj->tiling_mode == I915_TILING_Y)
2373                 val |= 1 << I830_FENCE_TILING_Y_SHIFT;
2374         val |= I830_FENCE_SIZE_BITS(size);
2375         val |= pitch_val << I830_FENCE_PITCH_SHIFT;
2376         val |= I830_FENCE_REG_VALID;
2377
2378         if (pipelined) {
2379                 int ret = intel_ring_begin(pipelined, 4);
2380                 if (ret)
2381                         return ret;
2382
2383                 intel_ring_emit(pipelined, MI_NOOP);
2384                 intel_ring_emit(pipelined, MI_LOAD_REGISTER_IMM(1));
2385                 intel_ring_emit(pipelined, FENCE_REG_830_0 + regnum*4);
2386                 intel_ring_emit(pipelined, val);
2387                 intel_ring_advance(pipelined);
2388         } else
2389                 I915_WRITE(FENCE_REG_830_0 + regnum * 4, val);
2390
2391         return 0;
2392 }
2393
2394 static bool ring_passed_seqno(struct intel_ring_buffer *ring, u32 seqno)
2395 {
2396         return i915_seqno_passed(ring->get_seqno(ring), seqno);
2397 }
2398
2399 static int
2400 i915_gem_object_flush_fence(struct drm_i915_gem_object *obj,
2401                             struct intel_ring_buffer *pipelined,
2402                             bool interruptible)
2403 {
2404         int ret;
2405
2406         if (obj->fenced_gpu_access) {
2407                 if (obj->base.write_domain & I915_GEM_GPU_DOMAINS) {
2408                         ret = i915_gem_flush_ring(obj->base.dev,
2409                                                   obj->last_fenced_ring,
2410                                                   0, obj->base.write_domain);
2411                         if (ret)
2412                                 return ret;
2413                 }
2414
2415                 obj->fenced_gpu_access = false;
2416         }
2417
2418         if (obj->last_fenced_seqno && pipelined != obj->last_fenced_ring) {
2419                 if (!ring_passed_seqno(obj->last_fenced_ring,
2420                                        obj->last_fenced_seqno)) {
2421                         ret = i915_do_wait_request(obj->base.dev,
2422                                                    obj->last_fenced_seqno,
2423                                                    interruptible,
2424                                                    obj->last_fenced_ring);
2425                         if (ret)
2426                                 return ret;
2427                 }
2428
2429                 obj->last_fenced_seqno = 0;
2430                 obj->last_fenced_ring = NULL;
2431         }
2432
2433         /* Ensure that all CPU reads are completed before installing a fence
2434          * and all writes before removing the fence.
2435          */
2436         if (obj->base.read_domains & I915_GEM_DOMAIN_GTT)
2437                 mb();
2438
2439         return 0;
2440 }
2441
2442 int
2443 i915_gem_object_put_fence(struct drm_i915_gem_object *obj)
2444 {
2445         int ret;
2446
2447         if (obj->tiling_mode)
2448                 i915_gem_release_mmap(obj);
2449
2450         ret = i915_gem_object_flush_fence(obj, NULL, true);
2451         if (ret)
2452                 return ret;
2453
2454         if (obj->fence_reg != I915_FENCE_REG_NONE) {
2455                 struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
2456                 i915_gem_clear_fence_reg(obj->base.dev,
2457                                          &dev_priv->fence_regs[obj->fence_reg]);
2458
2459                 obj->fence_reg = I915_FENCE_REG_NONE;
2460         }
2461
2462         return 0;
2463 }
2464
2465 static struct drm_i915_fence_reg *
2466 i915_find_fence_reg(struct drm_device *dev,
2467                     struct intel_ring_buffer *pipelined)
2468 {
2469         struct drm_i915_private *dev_priv = dev->dev_private;
2470         struct drm_i915_fence_reg *reg, *first, *avail;
2471         int i;
2472
2473         /* First try to find a free reg */
2474         avail = NULL;
2475         for (i = dev_priv->fence_reg_start; i < dev_priv->num_fence_regs; i++) {
2476                 reg = &dev_priv->fence_regs[i];
2477                 if (!reg->obj)
2478                         return reg;
2479
2480                 if (!reg->obj->pin_count)
2481                         avail = reg;
2482         }
2483
2484         if (avail == NULL)
2485                 return NULL;
2486
2487         /* None available, try to steal one or wait for a user to finish */
2488         avail = first = NULL;
2489         list_for_each_entry(reg, &dev_priv->mm.fence_list, lru_list) {
2490                 if (reg->obj->pin_count)
2491                         continue;
2492
2493                 if (first == NULL)
2494                         first = reg;
2495
2496                 if (!pipelined ||
2497                     !reg->obj->last_fenced_ring ||
2498                     reg->obj->last_fenced_ring == pipelined) {
2499                         avail = reg;
2500                         break;
2501                 }
2502         }
2503
2504         if (avail == NULL)
2505                 avail = first;
2506
2507         return avail;
2508 }
2509
2510 /**
2511  * i915_gem_object_get_fence - set up a fence reg for an object
2512  * @obj: object to map through a fence reg
2513  * @pipelined: ring on which to queue the change, or NULL for CPU access
2514  * @interruptible: must we wait uninterruptibly for the register to retire?
2515  *
2516  * When mapping objects through the GTT, userspace wants to be able to write
2517  * to them without having to worry about swizzling if the object is tiled.
2518  *
2519  * This function walks the fence regs looking for a free one for @obj,
2520  * stealing one if it can't find any.
2521  *
2522  * It then sets up the reg based on the object's properties: address, pitch
2523  * and tiling format.
2524  */
2525 int
2526 i915_gem_object_get_fence(struct drm_i915_gem_object *obj,
2527                           struct intel_ring_buffer *pipelined,
2528                           bool interruptible)
2529 {
2530         struct drm_device *dev = obj->base.dev;
2531         struct drm_i915_private *dev_priv = dev->dev_private;
2532         struct drm_i915_fence_reg *reg;
2533         int ret;
2534
2535         /* XXX disable pipelining. There are bugs. Shocking. */
2536         pipelined = NULL;
2537
2538         /* Just update our place in the LRU if our fence is getting reused. */
2539         if (obj->fence_reg != I915_FENCE_REG_NONE) {
2540                 reg = &dev_priv->fence_regs[obj->fence_reg];
2541                 list_move_tail(&reg->lru_list, &dev_priv->mm.fence_list);
2542
2543                 if (!obj->fenced_gpu_access && !obj->last_fenced_seqno)
2544                         pipelined = NULL;
2545
2546                 if (!pipelined) {
2547                         if (reg->setup_seqno) {
2548                                 if (!ring_passed_seqno(obj->last_fenced_ring,
2549                                                        reg->setup_seqno)) {
2550                                         ret = i915_do_wait_request(obj->base.dev,
2551                                                                    reg->setup_seqno,
2552                                                                    interruptible,
2553                                                                    obj->last_fenced_ring);
2554                                         if (ret)
2555                                                 return ret;
2556                                 }
2557
2558                                 reg->setup_seqno = 0;
2559                         }
2560                 } else if (obj->last_fenced_ring &&
2561                            obj->last_fenced_ring != pipelined) {
2562                         ret = i915_gem_object_flush_fence(obj,
2563                                                           pipelined,
2564                                                           interruptible);
2565                         if (ret)
2566                                 return ret;
2567                 } else if (obj->tiling_changed) {
2568                         if (obj->fenced_gpu_access) {
2569                                 if (obj->base.write_domain & I915_GEM_GPU_DOMAINS) {
2570                                         ret = i915_gem_flush_ring(obj->base.dev, obj->ring,
2571                                                                   0, obj->base.write_domain);
2572                                         if (ret)
2573                                                 return ret;
2574                                 }
2575
2576                                 obj->fenced_gpu_access = false;
2577                         }
2578                 }
2579
2580                 if (!obj->fenced_gpu_access && !obj->last_fenced_seqno)
2581                         pipelined = NULL;
2582                 BUG_ON(!pipelined && reg->setup_seqno);
2583
2584                 if (obj->tiling_changed) {
2585                         if (pipelined) {
2586                                 reg->setup_seqno =
2587                                         i915_gem_next_request_seqno(dev, pipelined);
2588                                 obj->last_fenced_seqno = reg->setup_seqno;
2589                                 obj->last_fenced_ring = pipelined;
2590                         }
2591                         goto update;
2592                 }
2593
2594                 return 0;
2595         }
2596
2597         reg = i915_find_fence_reg(dev, pipelined);
2598         if (reg == NULL)
2599                 return -ENOSPC;
2600
2601         ret = i915_gem_object_flush_fence(obj, pipelined, interruptible);
2602         if (ret)
2603                 return ret;
2604
2605         if (reg->obj) {
2606                 struct drm_i915_gem_object *old = reg->obj;
2607
2608                 drm_gem_object_reference(&old->base);
2609
2610                 if (old->tiling_mode)
2611                         i915_gem_release_mmap(old);
2612
2613                 ret = i915_gem_object_flush_fence(old,
2614                                                   pipelined,
2615                                                   interruptible);
2616                 if (ret) {
2617                         drm_gem_object_unreference(&old->base);
2618                         return ret;
2619                 }
2620
2621                 if (old->last_fenced_seqno == 0 && obj->last_fenced_seqno == 0)
2622                         pipelined = NULL;
2623
2624                 old->fence_reg = I915_FENCE_REG_NONE;
2625                 old->last_fenced_ring = pipelined;
2626                 old->last_fenced_seqno =
2627                         pipelined ? i915_gem_next_request_seqno(dev, pipelined) : 0;
2628
2629                 drm_gem_object_unreference(&old->base);
2630         } else if (obj->last_fenced_seqno == 0)
2631                 pipelined = NULL;
2632
2633         reg->obj = obj;
2634         list_move_tail(&reg->lru_list, &dev_priv->mm.fence_list);
2635         obj->fence_reg = reg - dev_priv->fence_regs;
2636         obj->last_fenced_ring = pipelined;
2637
2638         reg->setup_seqno =
2639                 pipelined ? i915_gem_next_request_seqno(dev, pipelined) : 0;
2640         obj->last_fenced_seqno = reg->setup_seqno;
2641
2642 update:
2643         obj->tiling_changed = false;
2644         switch (INTEL_INFO(dev)->gen) {
2645         case 6:
2646                 ret = sandybridge_write_fence_reg(obj, pipelined);
2647                 break;
2648         case 5:
2649         case 4:
2650                 ret = i965_write_fence_reg(obj, pipelined);
2651                 break;
2652         case 3:
2653                 ret = i915_write_fence_reg(obj, pipelined);
2654                 break;
2655         case 2:
2656                 ret = i830_write_fence_reg(obj, pipelined);
2657                 break;
2658         }
2659
2660         return ret;
2661 }
2662
2663 /**
2664  * i915_gem_clear_fence_reg - clear out fence register info
2665  * @obj: object to clear
2666  *
2667  * Zeroes out the fence register itself and clears out the associated
2668  * data structures in dev_priv and obj.
2669  */
2670 static void
2671 i915_gem_clear_fence_reg(struct drm_device *dev,
2672                          struct drm_i915_fence_reg *reg)
2673 {
2674         drm_i915_private_t *dev_priv = dev->dev_private;
2675         uint32_t fence_reg = reg - dev_priv->fence_regs;
2676
2677         switch (INTEL_INFO(dev)->gen) {
2678         case 6:
2679                 I915_WRITE64(FENCE_REG_SANDYBRIDGE_0 + fence_reg*8, 0);
2680                 break;
2681         case 5:
2682         case 4:
2683                 I915_WRITE64(FENCE_REG_965_0 + fence_reg*8, 0);
2684                 break;
2685         case 3:
2686                 if (fence_reg >= 8)
2687                         fence_reg = FENCE_REG_945_8 + (fence_reg - 8) * 4;
2688                 else
2689         case 2:
2690                         fence_reg = FENCE_REG_830_0 + fence_reg * 4;
2691
2692                 I915_WRITE(fence_reg, 0);
2693                 break;
2694         }
2695
2696         list_del_init(&reg->lru_list);
2697         reg->obj = NULL;
2698         reg->setup_seqno = 0;
2699 }
2700
2701 /**
2702  * Finds free space in the GTT aperture and binds the object there.
2703  */
2704 static int
2705 i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
2706                             unsigned alignment,
2707                             bool map_and_fenceable)
2708 {
2709         struct drm_device *dev = obj->base.dev;
2710         drm_i915_private_t *dev_priv = dev->dev_private;
2711         struct drm_mm_node *free_space;
2712         gfp_t gfpmask = __GFP_NORETRY | __GFP_NOWARN;
2713         u32 size, fence_size, fence_alignment, unfenced_alignment;
2714         bool mappable, fenceable;
2715         int ret;
2716
2717         if (obj->madv != I915_MADV_WILLNEED) {
2718                 DRM_ERROR("Attempting to bind a purgeable object\n");
2719                 return -EINVAL;
2720         }
2721
2722         fence_size = i915_gem_get_gtt_size(obj);
2723         fence_alignment = i915_gem_get_gtt_alignment(obj);
2724         unfenced_alignment = i915_gem_get_unfenced_gtt_alignment(obj);
2725
2726         if (alignment == 0)
2727                 alignment = map_and_fenceable ? fence_alignment :
2728                                                 unfenced_alignment;
2729         if (map_and_fenceable && alignment & (fence_alignment - 1)) {
2730                 DRM_ERROR("Invalid object alignment requested %u\n", alignment);
2731                 return -EINVAL;
2732         }
2733
2734         size = map_and_fenceable ? fence_size : obj->base.size;
2735
2736         /* If the object is bigger than the entire aperture, reject it early
2737          * before evicting everything in a vain attempt to find space.
2738          */
2739         if (obj->base.size >
2740             (map_and_fenceable ? dev_priv->mm.gtt_mappable_end : dev_priv->mm.gtt_total)) {
2741                 DRM_ERROR("Attempting to bind an object larger than the aperture\n");
2742                 return -E2BIG;
2743         }
2744
2745  search_free:
2746         if (map_and_fenceable)
2747                 free_space =
2748                         drm_mm_search_free_in_range(&dev_priv->mm.gtt_space,
2749                                                     size, alignment, 0,
2750                                                     dev_priv->mm.gtt_mappable_end,
2751                                                     0);
2752         else
2753                 free_space = drm_mm_search_free(&dev_priv->mm.gtt_space,
2754                                                 size, alignment, 0);
2755
2756         if (free_space != NULL) {
2757                 if (map_and_fenceable)
2758                         obj->gtt_space =
2759                                 drm_mm_get_block_range_generic(free_space,
2760                                                                size, alignment, 0,
2761                                                                dev_priv->mm.gtt_mappable_end,
2762                                                                0);
2763                 else
2764                         obj->gtt_space =
2765                                 drm_mm_get_block(free_space, size, alignment);
2766         }
2767         if (obj->gtt_space == NULL) {
2768                 /* If the gtt is empty and we're still having trouble
2769                  * fitting our object in, we're out of memory.
2770                  */
2771                 ret = i915_gem_evict_something(dev, size, alignment,
2772                                                map_and_fenceable);
2773                 if (ret)
2774                         return ret;
2775
2776                 goto search_free;
2777         }
2778
2779         ret = i915_gem_object_get_pages_gtt(obj, gfpmask);
2780         if (ret) {
2781                 drm_mm_put_block(obj->gtt_space);
2782                 obj->gtt_space = NULL;
2783
2784                 if (ret == -ENOMEM) {
2785                         /* first try to reclaim some memory by clearing the GTT */
2786                         ret = i915_gem_evict_everything(dev, false);
2787                         if (ret) {
2788                                 /* now try to shrink everyone else */
2789                                 if (gfpmask) {
2790                                         gfpmask = 0;
2791                                         goto search_free;
2792                                 }
2793
2794                                 return -ENOMEM;
2795                         }
2796
2797                         goto search_free;
2798                 }
2799
2800                 return ret;
2801         }
2802
2803         ret = i915_gem_gtt_bind_object(obj);
2804         if (ret) {
2805                 i915_gem_object_put_pages_gtt(obj);
2806                 drm_mm_put_block(obj->gtt_space);
2807                 obj->gtt_space = NULL;
2808
2809                 if (i915_gem_evict_everything(dev, false))
2810                         return ret;
2811
2812                 goto search_free;
2813         }
2814
2815         list_add_tail(&obj->gtt_list, &dev_priv->mm.gtt_list);
2816         list_add_tail(&obj->mm_list, &dev_priv->mm.inactive_list);
2817
2818         /* Assert that the object is not currently in any GPU domain. As it
2819          * wasn't in the GTT, there shouldn't be any way it could have been in
2820          * a GPU cache
2821          */
2822         BUG_ON(obj->base.read_domains & I915_GEM_GPU_DOMAINS);
2823         BUG_ON(obj->base.write_domain & I915_GEM_GPU_DOMAINS);
2824
2825         obj->gtt_offset = obj->gtt_space->start;
2826
2827         fenceable =
2828                 obj->gtt_space->size == fence_size &&
2829                 (obj->gtt_space->start & (fence_alignment -1)) == 0;
2830
2831         mappable =
2832                 obj->gtt_offset + obj->base.size <= dev_priv->mm.gtt_mappable_end;
2833
2834         obj->map_and_fenceable = mappable && fenceable;
2835
2836         trace_i915_gem_object_bind(obj, obj->gtt_offset, map_and_fenceable);
2837         return 0;
2838 }
2839
2840 void
2841 i915_gem_clflush_object(struct drm_i915_gem_object *obj)
2842 {
2843         /* If we don't have a page list set up, then we're not pinned
2844          * to GPU, and we can ignore the cache flush because it'll happen
2845          * again at bind time.
2846          */
2847         if (obj->pages == NULL)
2848                 return;
2849
2850         trace_i915_gem_object_clflush(obj);
2851
2852         drm_clflush_pages(obj->pages, obj->base.size / PAGE_SIZE);
2853 }
2854
2855 /** Flushes any GPU write domain for the object if it's dirty. */
2856 static int
2857 i915_gem_object_flush_gpu_write_domain(struct drm_i915_gem_object *obj)
2858 {
2859         struct drm_device *dev = obj->base.dev;
2860
2861         if ((obj->base.write_domain & I915_GEM_GPU_DOMAINS) == 0)
2862                 return 0;
2863
2864         /* Queue the GPU write cache flushing we need. */
2865         return i915_gem_flush_ring(dev, obj->ring, 0, obj->base.write_domain);
2866 }
2867
2868 /** Flushes the GTT write domain for the object if it's dirty. */
2869 static void
2870 i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj)
2871 {
2872         uint32_t old_write_domain;
2873
2874         if (obj->base.write_domain != I915_GEM_DOMAIN_GTT)
2875                 return;
2876
2877         /* No actual flushing is required for the GTT write domain.  Writes
2878          * to it immediately go to main memory as far as we know, so there's
2879          * no chipset flush.  It also doesn't land in render cache.
2880          *
2881          * However, we do have to enforce the order so that all writes through
2882          * the GTT land before any writes to the device, such as updates to
2883          * the GATT itself.
2884          */
2885         wmb();
2886
2887         i915_gem_release_mmap(obj);
2888
2889         old_write_domain = obj->base.write_domain;
2890         obj->base.write_domain = 0;
2891
2892         trace_i915_gem_object_change_domain(obj,
2893                                             obj->base.read_domains,
2894                                             old_write_domain);
2895 }
2896
2897 /** Flushes the CPU write domain for the object if it's dirty. */
2898 static void
2899 i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj)
2900 {
2901         uint32_t old_write_domain;
2902
2903         if (obj->base.write_domain != I915_GEM_DOMAIN_CPU)
2904                 return;
2905
2906         i915_gem_clflush_object(obj);
2907         intel_gtt_chipset_flush();
2908         old_write_domain = obj->base.write_domain;
2909         obj->base.write_domain = 0;
2910
2911         trace_i915_gem_object_change_domain(obj,
2912                                             obj->base.read_domains,
2913                                             old_write_domain);
2914 }
2915
2916 /**
2917  * Moves a single object to the GTT read, and possibly write domain.
2918  *
2919  * This function returns when the move is complete, including waiting on
2920  * flushes to occur.
2921  */
2922 int
2923 i915_gem_object_set_to_gtt_domain(struct drm_i915_gem_object *obj, bool write)
2924 {
2925         uint32_t old_write_domain, old_read_domains;
2926         int ret;
2927
2928         /* Not valid to be called on unbound objects. */
2929         if (obj->gtt_space == NULL)
2930                 return -EINVAL;
2931
2932         ret = i915_gem_object_flush_gpu_write_domain(obj);
2933         if (ret)
2934                 return ret;
2935
2936         if (obj->pending_gpu_write || write) {
2937                 ret = i915_gem_object_wait_rendering(obj, true);
2938                 if (ret)
2939                         return ret;
2940         }
2941
2942         i915_gem_object_flush_cpu_write_domain(obj);
2943
2944         old_write_domain = obj->base.write_domain;
2945         old_read_domains = obj->base.read_domains;
2946
2947         /* It should now be out of any other write domains, and we can update
2948          * the domain values for our changes.
2949          */
2950         BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_GTT) != 0);
2951         obj->base.read_domains |= I915_GEM_DOMAIN_GTT;
2952         if (write) {
2953                 obj->base.read_domains = I915_GEM_DOMAIN_GTT;
2954                 obj->base.write_domain = I915_GEM_DOMAIN_GTT;
2955                 obj->dirty = 1;
2956         }
2957
2958         trace_i915_gem_object_change_domain(obj,
2959                                             old_read_domains,
2960                                             old_write_domain);
2961
2962         return 0;
2963 }
2964
2965 /*
2966  * Prepare buffer for display plane. Use uninterruptible for possible flush
2967  * wait, as in modesetting process we're not supposed to be interrupted.
2968  */
2969 int
2970 i915_gem_object_set_to_display_plane(struct drm_i915_gem_object *obj,
2971                                      struct intel_ring_buffer *pipelined)
2972 {
2973         uint32_t old_read_domains;
2974         int ret;
2975
2976         /* Not valid to be called on unbound objects. */
2977         if (obj->gtt_space == NULL)
2978                 return -EINVAL;
2979
2980         ret = i915_gem_object_flush_gpu_write_domain(obj);
2981         if (ret)
2982                 return ret;
2983
2984
2985         /* Currently, we are always called from an non-interruptible context. */
2986         if (pipelined != obj->ring) {
2987                 ret = i915_gem_object_wait_rendering(obj, false);
2988                 if (ret)
2989                         return ret;
2990         }
2991
2992         i915_gem_object_flush_cpu_write_domain(obj);
2993
2994         old_read_domains = obj->base.read_domains;
2995         obj->base.read_domains |= I915_GEM_DOMAIN_GTT;
2996
2997         trace_i915_gem_object_change_domain(obj,
2998                                             old_read_domains,
2999                                             obj->base.write_domain);
3000
3001         return 0;
3002 }
3003
3004 int
3005 i915_gem_object_flush_gpu(struct drm_i915_gem_object *obj,
3006                           bool interruptible)
3007 {
3008         int ret;
3009
3010         if (!obj->active)
3011                 return 0;
3012
3013         if (obj->base.write_domain & I915_GEM_GPU_DOMAINS) {
3014                 ret = i915_gem_flush_ring(obj->base.dev, obj->ring,
3015                                           0, obj->base.write_domain);
3016                 if (ret)
3017                         return ret;
3018         }
3019
3020         return i915_gem_object_wait_rendering(obj, interruptible);
3021 }
3022
3023 /**
3024  * Moves a single object to the CPU read, and possibly write domain.
3025  *
3026  * This function returns when the move is complete, including waiting on
3027  * flushes to occur.
3028  */
3029 static int
3030 i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj, bool write)
3031 {
3032         uint32_t old_write_domain, old_read_domains;
3033         int ret;
3034
3035         ret = i915_gem_object_flush_gpu_write_domain(obj);
3036         if (ret)
3037                 return ret;
3038
3039         ret = i915_gem_object_wait_rendering(obj, true);
3040         if (ret)
3041                 return ret;
3042
3043         i915_gem_object_flush_gtt_write_domain(obj);
3044
3045         /* If we have a partially-valid cache of the object in the CPU,
3046          * finish invalidating it and free the per-page flags.
3047          */
3048         i915_gem_object_set_to_full_cpu_read_domain(obj);
3049
3050         old_write_domain = obj->base.write_domain;
3051         old_read_domains = obj->base.read_domains;
3052
3053         /* Flush the CPU cache if it's still invalid. */
3054         if ((obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0) {
3055                 i915_gem_clflush_object(obj);
3056
3057                 obj->base.read_domains |= I915_GEM_DOMAIN_CPU;
3058         }
3059
3060         /* It should now be out of any other write domains, and we can update
3061          * the domain values for our changes.
3062          */
3063         BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_CPU) != 0);
3064
3065         /* If we're writing through the CPU, then the GPU read domains will
3066          * need to be invalidated at next use.
3067          */
3068         if (write) {
3069                 obj->base.read_domains = I915_GEM_DOMAIN_CPU;
3070                 obj->base.write_domain = I915_GEM_DOMAIN_CPU;
3071         }
3072
3073         trace_i915_gem_object_change_domain(obj,
3074                                             old_read_domains,
3075                                             old_write_domain);
3076
3077         return 0;
3078 }
3079
3080 /**
3081  * Moves the object from a partially CPU read to a full one.
3082  *
3083  * Note that this only resolves i915_gem_object_set_cpu_read_domain_range(),
3084  * and doesn't handle transitioning from !(read_domains & I915_GEM_DOMAIN_CPU).
3085  */
3086 static void
3087 i915_gem_object_set_to_full_cpu_read_domain(struct drm_i915_gem_object *obj)
3088 {
3089         if (!obj->page_cpu_valid)
3090                 return;
3091
3092         /* If we're partially in the CPU read domain, finish moving it in.
3093          */
3094         if (obj->base.read_domains & I915_GEM_DOMAIN_CPU) {
3095                 int i;
3096
3097                 for (i = 0; i <= (obj->base.size - 1) / PAGE_SIZE; i++) {
3098                         if (obj->page_cpu_valid[i])
3099                                 continue;
3100                         drm_clflush_pages(obj->pages + i, 1);
3101                 }
3102         }
3103
3104         /* Free the page_cpu_valid mappings which are now stale, whether
3105          * or not we've got I915_GEM_DOMAIN_CPU.
3106          */
3107         kfree(obj->page_cpu_valid);
3108         obj->page_cpu_valid = NULL;
3109 }
3110
3111 /**
3112  * Set the CPU read domain on a range of the object.
3113  *
3114  * The object ends up with I915_GEM_DOMAIN_CPU in its read flags although it's
3115  * not entirely valid.  The page_cpu_valid member of the object flags which
3116  * pages have been flushed, and will be respected by
3117  * i915_gem_object_set_to_cpu_domain() if it's called on to get a valid mapping
3118  * of the whole object.
3119  *
3120  * This function returns when the move is complete, including waiting on
3121  * flushes to occur.
3122  */
3123 static int
3124 i915_gem_object_set_cpu_read_domain_range(struct drm_i915_gem_object *obj,
3125                                           uint64_t offset, uint64_t size)
3126 {
3127         uint32_t old_read_domains;
3128         int i, ret;
3129
3130         if (offset == 0 && size == obj->base.size)
3131                 return i915_gem_object_set_to_cpu_domain(obj, 0);
3132
3133         ret = i915_gem_object_flush_gpu_write_domain(obj);
3134         if (ret)
3135                 return ret;
3136
3137         ret = i915_gem_object_wait_rendering(obj, true);
3138         if (ret)
3139                 return ret;
3140
3141         i915_gem_object_flush_gtt_write_domain(obj);
3142
3143         /* If we're already fully in the CPU read domain, we're done. */
3144         if (obj->page_cpu_valid == NULL &&
3145             (obj->base.read_domains & I915_GEM_DOMAIN_CPU) != 0)
3146                 return 0;
3147
3148         /* Otherwise, create/clear the per-page CPU read domain flag if we're
3149          * newly adding I915_GEM_DOMAIN_CPU
3150          */
3151         if (obj->page_cpu_valid == NULL) {
3152                 obj->page_cpu_valid = kzalloc(obj->base.size / PAGE_SIZE,
3153                                               GFP_KERNEL);
3154                 if (obj->page_cpu_valid == NULL)
3155                         return -ENOMEM;
3156         } else if ((obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0)
3157                 memset(obj->page_cpu_valid, 0, obj->base.size / PAGE_SIZE);
3158
3159         /* Flush the cache on any pages that are still invalid from the CPU's
3160          * perspective.
3161          */
3162         for (i = offset / PAGE_SIZE; i <= (offset + size - 1) / PAGE_SIZE;
3163              i++) {
3164                 if (obj->page_cpu_valid[i])
3165                         continue;
3166
3167                 drm_clflush_pages(obj->pages + i, 1);
3168
3169                 obj->page_cpu_valid[i] = 1;
3170         }
3171
3172         /* It should now be out of any other write domains, and we can update
3173          * the domain values for our changes.
3174          */
3175         BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_CPU) != 0);
3176
3177         old_read_domains = obj->base.read_domains;
3178         obj->base.read_domains |= I915_GEM_DOMAIN_CPU;
3179
3180         trace_i915_gem_object_change_domain(obj,
3181                                             old_read_domains,
3182                                             obj->base.write_domain);
3183
3184         return 0;
3185 }
3186
3187 /* Throttle our rendering by waiting until the ring has completed our requests
3188  * emitted over 20 msec ago.
3189  *
3190  * Note that if we were to use the current jiffies each time around the loop,
3191  * we wouldn't escape the function with any frames outstanding if the time to
3192  * render a frame was over 20ms.
3193  *
3194  * This should get us reasonable parallelism between CPU and GPU but also
3195  * relatively low latency when blocking on a particular request to finish.
3196  */
3197 static int
3198 i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file)
3199 {
3200         struct drm_i915_private *dev_priv = dev->dev_private;
3201         struct drm_i915_file_private *file_priv = file->driver_priv;
3202         unsigned long recent_enough = jiffies - msecs_to_jiffies(20);
3203         struct drm_i915_gem_request *request;
3204         struct intel_ring_buffer *ring = NULL;
3205         u32 seqno = 0;
3206         int ret;
3207
3208         spin_lock(&file_priv->mm.lock);
3209         list_for_each_entry(request, &file_priv->mm.request_list, client_list) {
3210                 if (time_after_eq(request->emitted_jiffies, recent_enough))
3211                         break;
3212
3213                 ring = request->ring;
3214                 seqno = request->seqno;
3215         }
3216         spin_unlock(&file_priv->mm.lock);
3217
3218         if (seqno == 0)
3219                 return 0;
3220
3221         ret = 0;
3222         if (!i915_seqno_passed(ring->get_seqno(ring), seqno)) {
3223                 /* And wait for the seqno passing without holding any locks and
3224                  * causing extra latency for others. This is safe as the irq
3225                  * generation is designed to be run atomically and so is
3226                  * lockless.
3227                  */
3228                 if (ring->irq_get(ring)) {
3229                         ret = wait_event_interruptible(ring->irq_queue,
3230                                                        i915_seqno_passed(ring->get_seqno(ring), seqno)
3231                                                        || atomic_read(&dev_priv->mm.wedged));
3232                         ring->irq_put(ring);
3233
3234                         if (ret == 0 && atomic_read(&dev_priv->mm.wedged))
3235                                 ret = -EIO;
3236                 }
3237         }
3238
3239         if (ret == 0)
3240                 queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, 0);
3241
3242         return ret;
3243 }
3244
3245 int
3246 i915_gem_object_pin(struct drm_i915_gem_object *obj,
3247                     uint32_t alignment,
3248                     bool map_and_fenceable)
3249 {
3250         struct drm_device *dev = obj->base.dev;
3251         struct drm_i915_private *dev_priv = dev->dev_private;
3252         int ret;
3253
3254         BUG_ON(obj->pin_count == DRM_I915_GEM_OBJECT_MAX_PIN_COUNT);
3255         WARN_ON(i915_verify_lists(dev));
3256
3257         if (obj->gtt_space != NULL) {
3258                 if ((alignment && obj->gtt_offset & (alignment - 1)) ||
3259                     (map_and_fenceable && !obj->map_and_fenceable)) {
3260                         WARN(obj->pin_count,
3261                              "bo is already pinned with incorrect alignment:"
3262                              " offset=%x, req.alignment=%x, req.map_and_fenceable=%d,"
3263                              " obj->map_and_fenceable=%d\n",
3264                              obj->gtt_offset, alignment,
3265                              map_and_fenceable,
3266                              obj->map_and_fenceable);
3267                         ret = i915_gem_object_unbind(obj);
3268                         if (ret)
3269                                 return ret;
3270                 }
3271         }
3272
3273         if (obj->gtt_space == NULL) {
3274                 ret = i915_gem_object_bind_to_gtt(obj, alignment,
3275                                                   map_and_fenceable);
3276                 if (ret)
3277                         return ret;
3278         }
3279
3280         if (obj->pin_count++ == 0) {
3281                 if (!obj->active)
3282                         list_move_tail(&obj->mm_list,
3283                                        &dev_priv->mm.pinned_list);
3284         }
3285         obj->pin_mappable |= map_and_fenceable;
3286
3287         WARN_ON(i915_verify_lists(dev));
3288         return 0;
3289 }
3290
3291 void
3292 i915_gem_object_unpin(struct drm_i915_gem_object *obj)
3293 {
3294         struct drm_device *dev = obj->base.dev;
3295         drm_i915_private_t *dev_priv = dev->dev_private;
3296
3297         WARN_ON(i915_verify_lists(dev));
3298         BUG_ON(obj->pin_count == 0);
3299         BUG_ON(obj->gtt_space == NULL);
3300
3301         if (--obj->pin_count == 0) {
3302                 if (!obj->active)
3303                         list_move_tail(&obj->mm_list,
3304                                        &dev_priv->mm.inactive_list);
3305                 obj->pin_mappable = false;
3306         }
3307         WARN_ON(i915_verify_lists(dev));
3308 }
3309
3310 int
3311 i915_gem_pin_ioctl(struct drm_device *dev, void *data,
3312                    struct drm_file *file)
3313 {
3314         struct drm_i915_gem_pin *args = data;
3315         struct drm_i915_gem_object *obj;
3316         int ret;
3317
3318         ret = i915_mutex_lock_interruptible(dev);
3319         if (ret)
3320                 return ret;
3321
3322         obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
3323         if (obj == NULL) {
3324                 ret = -ENOENT;
3325                 goto unlock;
3326         }
3327
3328         if (obj->madv != I915_MADV_WILLNEED) {
3329                 DRM_ERROR("Attempting to pin a purgeable buffer\n");
3330                 ret = -EINVAL;
3331                 goto out;
3332         }
3333
3334         if (obj->pin_filp != NULL && obj->pin_filp != file) {
3335                 DRM_ERROR("Already pinned in i915_gem_pin_ioctl(): %d\n",
3336                           args->handle);
3337                 ret = -EINVAL;
3338                 goto out;
3339         }
3340
3341         obj->user_pin_count++;
3342         obj->pin_filp = file;
3343         if (obj->user_pin_count == 1) {
3344                 ret = i915_gem_object_pin(obj, args->alignment, true);
3345                 if (ret)
3346                         goto out;
3347         }
3348
3349         /* XXX - flush the CPU caches for pinned objects
3350          * as the X server doesn't manage domains yet
3351          */
3352         i915_gem_object_flush_cpu_write_domain(obj);
3353         args->offset = obj->gtt_offset;
3354 out:
3355         drm_gem_object_unreference(&obj->base);
3356 unlock:
3357         mutex_unlock(&dev->struct_mutex);
3358         return ret;
3359 }
3360
3361 int
3362 i915_gem_unpin_ioctl(struct drm_device *dev, void *data,
3363                      struct drm_file *file)
3364 {
3365         struct drm_i915_gem_pin *args = data;
3366         struct drm_i915_gem_object *obj;
3367         int ret;
3368
3369         ret = i915_mutex_lock_interruptible(dev);
3370         if (ret)
3371                 return ret;
3372
3373         obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
3374         if (obj == NULL) {
3375                 ret = -ENOENT;
3376                 goto unlock;
3377         }
3378
3379         if (obj->pin_filp != file) {
3380                 DRM_ERROR("Not pinned by caller in i915_gem_pin_ioctl(): %d\n",
3381                           args->handle);
3382                 ret = -EINVAL;
3383                 goto out;
3384         }
3385         obj->user_pin_count--;
3386         if (obj->user_pin_count == 0) {
3387                 obj->pin_filp = NULL;
3388                 i915_gem_object_unpin(obj);
3389         }
3390
3391 out:
3392         drm_gem_object_unreference(&obj->base);
3393 unlock:
3394         mutex_unlock(&dev->struct_mutex);
3395         return ret;
3396 }
3397
3398 int
3399 i915_gem_busy_ioctl(struct drm_device *dev, void *data,
3400                     struct drm_file *file)
3401 {
3402         struct drm_i915_gem_busy *args = data;
3403         struct drm_i915_gem_object *obj;
3404         int ret;
3405
3406         ret = i915_mutex_lock_interruptible(dev);
3407         if (ret)
3408                 return ret;
3409
3410         obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
3411         if (obj == NULL) {
3412                 ret = -ENOENT;
3413                 goto unlock;
3414         }
3415
3416         /* Count all active objects as busy, even if they are currently not used
3417          * by the gpu. Users of this interface expect objects to eventually
3418          * become non-busy without any further actions, therefore emit any
3419          * necessary flushes here.
3420          */
3421         args->busy = obj->active;
3422         if (args->busy) {
3423                 /* Unconditionally flush objects, even when the gpu still uses this
3424                  * object. Userspace calling this function indicates that it wants to
3425                  * use this buffer rather sooner than later, so issuing the required
3426                  * flush earlier is beneficial.
3427                  */
3428                 if (obj->base.write_domain & I915_GEM_GPU_DOMAINS) {
3429                         ret = i915_gem_flush_ring(dev, obj->ring,
3430                                                   0, obj->base.write_domain);
3431                 } else if (obj->ring->outstanding_lazy_request ==
3432                            obj->last_rendering_seqno) {
3433                         struct drm_i915_gem_request *request;
3434
3435                         /* This ring is not being cleared by active usage,
3436                          * so emit a request to do so.
3437                          */
3438                         request = kzalloc(sizeof(*request), GFP_KERNEL);
3439                         if (request)
3440                                 ret = i915_add_request(dev,
3441                                                        NULL, request,
3442                                                        obj->ring);
3443                         else
3444                                 ret = -ENOMEM;
3445                 }
3446
3447                 /* Update the active list for the hardware's current position.
3448                  * Otherwise this only updates on a delayed timer or when irqs
3449                  * are actually unmasked, and our working set ends up being
3450                  * larger than required.
3451                  */
3452                 i915_gem_retire_requests_ring(dev, obj->ring);
3453
3454                 args->busy = obj->active;
3455         }
3456
3457         drm_gem_object_unreference(&obj->base);
3458 unlock:
3459         mutex_unlock(&dev->struct_mutex);
3460         return ret;
3461 }
3462
3463 int
3464 i915_gem_throttle_ioctl(struct drm_device *dev, void *data,
3465                         struct drm_file *file_priv)
3466 {
3467     return i915_gem_ring_throttle(dev, file_priv);
3468 }
3469
3470 int
3471 i915_gem_madvise_ioctl(struct drm_device *dev, void *data,
3472                        struct drm_file *file_priv)
3473 {
3474         struct drm_i915_gem_madvise *args = data;
3475         struct drm_i915_gem_object *obj;
3476         int ret;
3477
3478         switch (args->madv) {
3479         case I915_MADV_DONTNEED:
3480         case I915_MADV_WILLNEED:
3481             break;
3482         default:
3483             return -EINVAL;
3484         }
3485
3486         ret = i915_mutex_lock_interruptible(dev);
3487         if (ret)
3488                 return ret;
3489
3490         obj = to_intel_bo(drm_gem_object_lookup(dev, file_priv, args->handle));
3491         if (obj == NULL) {
3492                 ret = -ENOENT;
3493                 goto unlock;
3494         }
3495
3496         if (obj->pin_count) {
3497                 ret = -EINVAL;
3498                 goto out;
3499         }
3500
3501         if (obj->madv != __I915_MADV_PURGED)
3502                 obj->madv = args->madv;
3503
3504         /* if the object is no longer bound, discard its backing storage */
3505         if (i915_gem_object_is_purgeable(obj) &&
3506             obj->gtt_space == NULL)
3507                 i915_gem_object_truncate(obj);
3508
3509         args->retained = obj->madv != __I915_MADV_PURGED;
3510
3511 out:
3512         drm_gem_object_unreference(&obj->base);
3513 unlock:
3514         mutex_unlock(&dev->struct_mutex);
3515         return ret;
3516 }
3517
3518 struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
3519                                                   size_t size)
3520 {
3521         struct drm_i915_private *dev_priv = dev->dev_private;
3522         struct drm_i915_gem_object *obj;
3523
3524         obj = kzalloc(sizeof(*obj), GFP_KERNEL);
3525         if (obj == NULL)
3526                 return NULL;
3527
3528         if (drm_gem_object_init(dev, &obj->base, size) != 0) {
3529                 kfree(obj);
3530                 return NULL;
3531         }
3532
3533         i915_gem_info_add_obj(dev_priv, size);
3534
3535         obj->base.write_domain = I915_GEM_DOMAIN_CPU;
3536         obj->base.read_domains = I915_GEM_DOMAIN_CPU;
3537
3538         obj->agp_type = AGP_USER_MEMORY;
3539         obj->base.driver_private = NULL;
3540         obj->fence_reg = I915_FENCE_REG_NONE;
3541         INIT_LIST_HEAD(&obj->mm_list);
3542         INIT_LIST_HEAD(&obj->gtt_list);
3543         INIT_LIST_HEAD(&obj->ring_list);
3544         INIT_LIST_HEAD(&obj->exec_list);
3545         INIT_LIST_HEAD(&obj->gpu_write_list);
3546         obj->madv = I915_MADV_WILLNEED;
3547         /* Avoid an unnecessary call to unbind on the first bind. */
3548         obj->map_and_fenceable = true;
3549
3550         return obj;
3551 }
3552
3553 int i915_gem_init_object(struct drm_gem_object *obj)
3554 {
3555         BUG();
3556
3557         return 0;
3558 }
3559
3560 static void i915_gem_free_object_tail(struct drm_i915_gem_object *obj)
3561 {
3562         struct drm_device *dev = obj->base.dev;
3563         drm_i915_private_t *dev_priv = dev->dev_private;
3564         int ret;
3565
3566         ret = i915_gem_object_unbind(obj);
3567         if (ret == -ERESTARTSYS) {
3568                 list_move(&obj->mm_list,
3569                           &dev_priv->mm.deferred_free_list);
3570                 return;
3571         }
3572
3573         if (obj->base.map_list.map)
3574                 i915_gem_free_mmap_offset(obj);
3575
3576         drm_gem_object_release(&obj->base);
3577         i915_gem_info_remove_obj(dev_priv, obj->base.size);
3578
3579         kfree(obj->page_cpu_valid);
3580         kfree(obj->bit_17);
3581         kfree(obj);
3582 }
3583
3584 void i915_gem_free_object(struct drm_gem_object *gem_obj)
3585 {
3586         struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
3587         struct drm_device *dev = obj->base.dev;
3588
3589         trace_i915_gem_object_destroy(obj);
3590
3591         while (obj->pin_count > 0)
3592                 i915_gem_object_unpin(obj);
3593
3594         if (obj->phys_obj)
3595                 i915_gem_detach_phys_object(dev, obj);
3596
3597         i915_gem_free_object_tail(obj);
3598 }
3599
3600 int
3601 i915_gem_idle(struct drm_device *dev)
3602 {
3603         drm_i915_private_t *dev_priv = dev->dev_private;
3604         int ret;
3605
3606         mutex_lock(&dev->struct_mutex);
3607
3608         if (dev_priv->mm.suspended) {
3609                 mutex_unlock(&dev->struct_mutex);
3610                 return 0;
3611         }
3612
3613         ret = i915_gpu_idle(dev);
3614         if (ret) {
3615                 mutex_unlock(&dev->struct_mutex);
3616                 return ret;
3617         }
3618
3619         /* Under UMS, be paranoid and evict. */
3620         if (!drm_core_check_feature(dev, DRIVER_MODESET)) {
3621                 ret = i915_gem_evict_inactive(dev, false);
3622                 if (ret) {
3623                         mutex_unlock(&dev->struct_mutex);
3624                         return ret;
3625                 }
3626         }
3627
3628         i915_gem_reset_fences(dev);
3629
3630         /* Hack!  Don't let anybody do execbuf while we don't control the chip.
3631          * We need to replace this with a semaphore, or something.
3632          * And not confound mm.suspended!
3633          */
3634         dev_priv->mm.suspended = 1;
3635         del_timer_sync(&dev_priv->hangcheck_timer);
3636
3637         i915_kernel_lost_context(dev);
3638         i915_gem_cleanup_ringbuffer(dev);
3639
3640         mutex_unlock(&dev->struct_mutex);
3641
3642         /* Cancel the retire work handler, which should be idle now. */
3643         cancel_delayed_work_sync(&dev_priv->mm.retire_work);
3644
3645         return 0;
3646 }
3647
3648 int
3649 i915_gem_init_ringbuffer(struct drm_device *dev)
3650 {
3651         drm_i915_private_t *dev_priv = dev->dev_private;
3652         int ret;
3653
3654         ret = intel_init_render_ring_buffer(dev);
3655         if (ret)
3656                 return ret;
3657
3658         if (HAS_BSD(dev)) {
3659                 ret = intel_init_bsd_ring_buffer(dev);
3660                 if (ret)
3661                         goto cleanup_render_ring;
3662         }
3663
3664         if (HAS_BLT(dev)) {
3665                 ret = intel_init_blt_ring_buffer(dev);
3666                 if (ret)
3667                         goto cleanup_bsd_ring;
3668         }
3669
3670         dev_priv->next_seqno = 1;
3671
3672         return 0;
3673
3674 cleanup_bsd_ring:
3675         intel_cleanup_ring_buffer(&dev_priv->ring[VCS]);
3676 cleanup_render_ring:
3677         intel_cleanup_ring_buffer(&dev_priv->ring[RCS]);
3678         return ret;
3679 }
3680
3681 void
3682 i915_gem_cleanup_ringbuffer(struct drm_device *dev)
3683 {
3684         drm_i915_private_t *dev_priv = dev->dev_private;
3685         int i;
3686
3687         for (i = 0; i < I915_NUM_RINGS; i++)
3688                 intel_cleanup_ring_buffer(&dev_priv->ring[i]);
3689 }
3690
3691 int
3692 i915_gem_entervt_ioctl(struct drm_device *dev, void *data,
3693                        struct drm_file *file_priv)
3694 {
3695         drm_i915_private_t *dev_priv = dev->dev_private;
3696         int ret, i;
3697
3698         if (drm_core_check_feature(dev, DRIVER_MODESET))
3699                 return 0;
3700
3701         if (atomic_read(&dev_priv->mm.wedged)) {
3702                 DRM_ERROR("Reenabling wedged hardware, good luck\n");
3703                 atomic_set(&dev_priv->mm.wedged, 0);
3704         }
3705
3706         mutex_lock(&dev->struct_mutex);
3707         dev_priv->mm.suspended = 0;
3708
3709         ret = i915_gem_init_ringbuffer(dev);
3710         if (ret != 0) {
3711                 mutex_unlock(&dev->struct_mutex);
3712                 return ret;
3713         }
3714
3715         BUG_ON(!list_empty(&dev_priv->mm.active_list));
3716         BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
3717         BUG_ON(!list_empty(&dev_priv->mm.inactive_list));
3718         for (i = 0; i < I915_NUM_RINGS; i++) {
3719                 BUG_ON(!list_empty(&dev_priv->ring[i].active_list));
3720                 BUG_ON(!list_empty(&dev_priv->ring[i].request_list));
3721         }
3722         mutex_unlock(&dev->struct_mutex);
3723
3724         ret = drm_irq_install(dev);
3725         if (ret)
3726                 goto cleanup_ringbuffer;
3727
3728         return 0;
3729
3730 cleanup_ringbuffer:
3731         mutex_lock(&dev->struct_mutex);
3732         i915_gem_cleanup_ringbuffer(dev);
3733         dev_priv->mm.suspended = 1;
3734         mutex_unlock(&dev->struct_mutex);
3735
3736         return ret;
3737 }
3738
3739 int
3740 i915_gem_leavevt_ioctl(struct drm_device *dev, void *data,
3741                        struct drm_file *file_priv)
3742 {
3743         if (drm_core_check_feature(dev, DRIVER_MODESET))
3744                 return 0;
3745
3746         drm_irq_uninstall(dev);
3747         return i915_gem_idle(dev);
3748 }
3749
3750 void
3751 i915_gem_lastclose(struct drm_device *dev)
3752 {
3753         int ret;
3754
3755         if (drm_core_check_feature(dev, DRIVER_MODESET))
3756                 return;
3757
3758         ret = i915_gem_idle(dev);
3759         if (ret)
3760                 DRM_ERROR("failed to idle hardware: %d\n", ret);
3761 }
3762
3763 static void
3764 init_ring_lists(struct intel_ring_buffer *ring)
3765 {
3766         INIT_LIST_HEAD(&ring->active_list);
3767         INIT_LIST_HEAD(&ring->request_list);
3768         INIT_LIST_HEAD(&ring->gpu_write_list);
3769 }
3770
3771 void
3772 i915_gem_load(struct drm_device *dev)
3773 {
3774         int i;
3775         drm_i915_private_t *dev_priv = dev->dev_private;
3776
3777         INIT_LIST_HEAD(&dev_priv->mm.active_list);
3778         INIT_LIST_HEAD(&dev_priv->mm.flushing_list);
3779         INIT_LIST_HEAD(&dev_priv->mm.inactive_list);
3780         INIT_LIST_HEAD(&dev_priv->mm.pinned_list);
3781         INIT_LIST_HEAD(&dev_priv->mm.fence_list);
3782         INIT_LIST_HEAD(&dev_priv->mm.deferred_free_list);
3783         INIT_LIST_HEAD(&dev_priv->mm.gtt_list);
3784         for (i = 0; i < I915_NUM_RINGS; i++)
3785                 init_ring_lists(&dev_priv->ring[i]);
3786         for (i = 0; i < 16; i++)
3787                 INIT_LIST_HEAD(&dev_priv->fence_regs[i].lru_list);
3788         INIT_DELAYED_WORK(&dev_priv->mm.retire_work,
3789                           i915_gem_retire_work_handler);
3790         init_completion(&dev_priv->error_completion);
3791
3792         /* On GEN3 we really need to make sure the ARB C3 LP bit is set */
3793         if (IS_GEN3(dev)) {
3794                 u32 tmp = I915_READ(MI_ARB_STATE);
3795                 if (!(tmp & MI_ARB_C3_LP_WRITE_ENABLE)) {
3796                         /* arb state is a masked write, so set bit + bit in mask */
3797                         tmp = MI_ARB_C3_LP_WRITE_ENABLE | (MI_ARB_C3_LP_WRITE_ENABLE << MI_ARB_MASK_SHIFT);
3798                         I915_WRITE(MI_ARB_STATE, tmp);
3799                 }
3800         }
3801
3802         dev_priv->relative_constants_mode = I915_EXEC_CONSTANTS_REL_GENERAL;
3803
3804         /* Old X drivers will take 0-2 for front, back, depth buffers */
3805         if (!drm_core_check_feature(dev, DRIVER_MODESET))
3806                 dev_priv->fence_reg_start = 3;
3807
3808         if (INTEL_INFO(dev)->gen >= 4 || IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev))
3809                 dev_priv->num_fence_regs = 16;
3810         else
3811                 dev_priv->num_fence_regs = 8;
3812
3813         /* Initialize fence registers to zero */
3814         switch (INTEL_INFO(dev)->gen) {
3815         case 6:
3816                 for (i = 0; i < 16; i++)
3817                         I915_WRITE64(FENCE_REG_SANDYBRIDGE_0 + (i * 8), 0);
3818                 break;
3819         case 5:
3820         case 4:
3821                 for (i = 0; i < 16; i++)
3822                         I915_WRITE64(FENCE_REG_965_0 + (i * 8), 0);
3823                 break;
3824         case 3:
3825                 if (IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev))
3826                         for (i = 0; i < 8; i++)
3827                                 I915_WRITE(FENCE_REG_945_8 + (i * 4), 0);
3828         case 2:
3829                 for (i = 0; i < 8; i++)
3830                         I915_WRITE(FENCE_REG_830_0 + (i * 4), 0);
3831                 break;
3832         }
3833         i915_gem_detect_bit_6_swizzle(dev);
3834         init_waitqueue_head(&dev_priv->pending_flip_queue);
3835
3836         dev_priv->mm.inactive_shrinker.shrink = i915_gem_inactive_shrink;
3837         dev_priv->mm.inactive_shrinker.seeks = DEFAULT_SEEKS;
3838         register_shrinker(&dev_priv->mm.inactive_shrinker);
3839 }
3840
3841 /*
3842  * Create a physically contiguous memory object for this object
3843  * e.g. for cursor + overlay regs
3844  */
3845 static int i915_gem_init_phys_object(struct drm_device *dev,
3846                                      int id, int size, int align)
3847 {
3848         drm_i915_private_t *dev_priv = dev->dev_private;
3849         struct drm_i915_gem_phys_object *phys_obj;
3850         int ret;
3851
3852         if (dev_priv->mm.phys_objs[id - 1] || !size)
3853                 return 0;
3854
3855         phys_obj = kzalloc(sizeof(struct drm_i915_gem_phys_object), GFP_KERNEL);
3856         if (!phys_obj)
3857                 return -ENOMEM;
3858
3859         phys_obj->id = id;
3860
3861         phys_obj->handle = drm_pci_alloc(dev, size, align);
3862         if (!phys_obj->handle) {
3863                 ret = -ENOMEM;
3864                 goto kfree_obj;
3865         }
3866 #ifdef CONFIG_X86
3867         set_memory_wc((unsigned long)phys_obj->handle->vaddr, phys_obj->handle->size / PAGE_SIZE);
3868 #endif
3869
3870         dev_priv->mm.phys_objs[id - 1] = phys_obj;
3871
3872         return 0;
3873 kfree_obj:
3874         kfree(phys_obj);
3875         return ret;
3876 }
3877
3878 static void i915_gem_free_phys_object(struct drm_device *dev, int id)
3879 {
3880         drm_i915_private_t *dev_priv = dev->dev_private;
3881         struct drm_i915_gem_phys_object *phys_obj;
3882
3883         if (!dev_priv->mm.phys_objs[id - 1])
3884                 return;
3885
3886         phys_obj = dev_priv->mm.phys_objs[id - 1];
3887         if (phys_obj->cur_obj) {
3888                 i915_gem_detach_phys_object(dev, phys_obj->cur_obj);
3889         }
3890
3891 #ifdef CONFIG_X86
3892         set_memory_wb((unsigned long)phys_obj->handle->vaddr, phys_obj->handle->size / PAGE_SIZE);
3893 #endif
3894         drm_pci_free(dev, phys_obj->handle);
3895         kfree(phys_obj);
3896         dev_priv->mm.phys_objs[id - 1] = NULL;
3897 }
3898
3899 void i915_gem_free_all_phys_object(struct drm_device *dev)
3900 {
3901         int i;
3902
3903         for (i = I915_GEM_PHYS_CURSOR_0; i <= I915_MAX_PHYS_OBJECT; i++)
3904                 i915_gem_free_phys_object(dev, i);
3905 }
3906
3907 void i915_gem_detach_phys_object(struct drm_device *dev,
3908                                  struct drm_i915_gem_object *obj)
3909 {
3910         struct address_space *mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping;
3911         char *vaddr;
3912         int i;
3913         int page_count;
3914
3915         if (!obj->phys_obj)
3916                 return;
3917         vaddr = obj->phys_obj->handle->vaddr;
3918
3919         page_count = obj->base.size / PAGE_SIZE;
3920         for (i = 0; i < page_count; i++) {
3921                 struct page *page = read_cache_page_gfp(mapping, i,
3922                                                         GFP_HIGHUSER | __GFP_RECLAIMABLE);
3923                 if (!IS_ERR(page)) {
3924                         char *dst = kmap_atomic(page);
3925                         memcpy(dst, vaddr + i*PAGE_SIZE, PAGE_SIZE);
3926                         kunmap_atomic(dst);
3927
3928                         drm_clflush_pages(&page, 1);
3929
3930                         set_page_dirty(page);
3931                         mark_page_accessed(page);
3932                         page_cache_release(page);
3933                 }
3934         }
3935         intel_gtt_chipset_flush();
3936
3937         obj->phys_obj->cur_obj = NULL;
3938         obj->phys_obj = NULL;
3939 }
3940
3941 int
3942 i915_gem_attach_phys_object(struct drm_device *dev,
3943                             struct drm_i915_gem_object *obj,
3944                             int id,
3945                             int align)
3946 {
3947         struct address_space *mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping;
3948         drm_i915_private_t *dev_priv = dev->dev_private;
3949         int ret = 0;
3950         int page_count;
3951         int i;
3952
3953         if (id > I915_MAX_PHYS_OBJECT)
3954                 return -EINVAL;
3955
3956         if (obj->phys_obj) {
3957                 if (obj->phys_obj->id == id)
3958                         return 0;
3959                 i915_gem_detach_phys_object(dev, obj);
3960         }
3961
3962         /* create a new object */
3963         if (!dev_priv->mm.phys_objs[id - 1]) {
3964                 ret = i915_gem_init_phys_object(dev, id,
3965                                                 obj->base.size, align);
3966                 if (ret) {
3967                         DRM_ERROR("failed to init phys object %d size: %zu\n",
3968                                   id, obj->base.size);
3969                         return ret;
3970                 }
3971         }
3972
3973         /* bind to the object */
3974         obj->phys_obj = dev_priv->mm.phys_objs[id - 1];
3975         obj->phys_obj->cur_obj = obj;
3976
3977         page_count = obj->base.size / PAGE_SIZE;
3978
3979         for (i = 0; i < page_count; i++) {
3980                 struct page *page;
3981                 char *dst, *src;
3982
3983                 page = read_cache_page_gfp(mapping, i,
3984                                            GFP_HIGHUSER | __GFP_RECLAIMABLE);
3985                 if (IS_ERR(page))
3986                         return PTR_ERR(page);
3987
3988                 src = kmap_atomic(page);
3989                 dst = obj->phys_obj->handle->vaddr + (i * PAGE_SIZE);
3990                 memcpy(dst, src, PAGE_SIZE);
3991                 kunmap_atomic(src);
3992
3993                 mark_page_accessed(page);
3994                 page_cache_release(page);
3995         }
3996
3997         return 0;
3998 }
3999
4000 static int
4001 i915_gem_phys_pwrite(struct drm_device *dev,
4002                      struct drm_i915_gem_object *obj,
4003                      struct drm_i915_gem_pwrite *args,
4004                      struct drm_file *file_priv)
4005 {
4006         void *vaddr = obj->phys_obj->handle->vaddr + args->offset;
4007         char __user *user_data = (char __user *) (uintptr_t) args->data_ptr;
4008
4009         if (__copy_from_user_inatomic_nocache(vaddr, user_data, args->size)) {
4010                 unsigned long unwritten;
4011
4012                 /* The physical object once assigned is fixed for the lifetime
4013                  * of the obj, so we can safely drop the lock and continue
4014                  * to access vaddr.
4015                  */
4016                 mutex_unlock(&dev->struct_mutex);
4017                 unwritten = copy_from_user(vaddr, user_data, args->size);
4018                 mutex_lock(&dev->struct_mutex);
4019                 if (unwritten)
4020                         return -EFAULT;
4021         }
4022
4023         intel_gtt_chipset_flush();
4024         return 0;
4025 }
4026
4027 void i915_gem_release(struct drm_device *dev, struct drm_file *file)
4028 {
4029         struct drm_i915_file_private *file_priv = file->driver_priv;
4030
4031         /* Clean up our request list when the client is going away, so that
4032          * later retire_requests won't dereference our soon-to-be-gone
4033          * file_priv.
4034          */
4035         spin_lock(&file_priv->mm.lock);
4036         while (!list_empty(&file_priv->mm.request_list)) {
4037                 struct drm_i915_gem_request *request;
4038
4039                 request = list_first_entry(&file_priv->mm.request_list,
4040                                            struct drm_i915_gem_request,
4041                                            client_list);
4042                 list_del(&request->client_list);
4043                 request->file_priv = NULL;
4044         }
4045         spin_unlock(&file_priv->mm.lock);
4046 }
4047
4048 static int
4049 i915_gpu_is_active(struct drm_device *dev)
4050 {
4051         drm_i915_private_t *dev_priv = dev->dev_private;
4052         int lists_empty;
4053
4054         lists_empty = list_empty(&dev_priv->mm.flushing_list) &&
4055                       list_empty(&dev_priv->mm.active_list);
4056
4057         return !lists_empty;
4058 }
4059
4060 static int
4061 i915_gem_inactive_shrink(struct shrinker *shrinker,
4062                          int nr_to_scan,
4063                          gfp_t gfp_mask)
4064 {
4065         struct drm_i915_private *dev_priv =
4066                 container_of(shrinker,
4067                              struct drm_i915_private,
4068                              mm.inactive_shrinker);
4069         struct drm_device *dev = dev_priv->dev;
4070         struct drm_i915_gem_object *obj, *next;
4071         int cnt;
4072
4073         if (!mutex_trylock(&dev->struct_mutex))
4074                 return 0;
4075
4076         /* "fast-path" to count number of available objects */
4077         if (nr_to_scan == 0) {
4078                 cnt = 0;
4079                 list_for_each_entry(obj,
4080                                     &dev_priv->mm.inactive_list,
4081                                     mm_list)
4082                         cnt++;
4083                 mutex_unlock(&dev->struct_mutex);
4084                 return cnt / 100 * sysctl_vfs_cache_pressure;
4085         }
4086
4087 rescan:
4088         /* first scan for clean buffers */
4089         i915_gem_retire_requests(dev);
4090
4091         list_for_each_entry_safe(obj, next,
4092                                  &dev_priv->mm.inactive_list,
4093                                  mm_list) {
4094                 if (i915_gem_object_is_purgeable(obj)) {
4095                         if (i915_gem_object_unbind(obj) == 0 &&
4096                             --nr_to_scan == 0)
4097                                 break;
4098                 }
4099         }
4100
4101         /* second pass, evict/count anything still on the inactive list */
4102         cnt = 0;
4103         list_for_each_entry_safe(obj, next,
4104                                  &dev_priv->mm.inactive_list,
4105                                  mm_list) {
4106                 if (nr_to_scan &&
4107                     i915_gem_object_unbind(obj) == 0)
4108                         nr_to_scan--;
4109                 else
4110                         cnt++;
4111         }
4112
4113         if (nr_to_scan && i915_gpu_is_active(dev)) {
4114                 /*
4115                  * We are desperate for pages, so as a last resort, wait
4116                  * for the GPU to finish and discard whatever we can.
4117                  * This has a dramatic impact to reduce the number of
4118                  * OOM-killer events whilst running the GPU aggressively.
4119                  */
4120                 if (i915_gpu_idle(dev) == 0)
4121                         goto rescan;
4122         }
4123         mutex_unlock(&dev->struct_mutex);
4124         return cnt / 100 * sysctl_vfs_cache_pressure;
4125 }