1 /*
2  * Copyright (C) 2015 Etnaviv Project
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License version 2 as published by
6  * the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program.  If not, see <http://www.gnu.org/licenses/>.
15  */
16 
17 #include <linux/spinlock.h>
18 #include <linux/shmem_fs.h>
19 
20 #include "etnaviv_drv.h"
21 #include "etnaviv_gem.h"
22 #include "etnaviv_gpu.h"
23 #include "etnaviv_mmu.h"
24 
25 static void etnaviv_gem_scatter_map(struct etnaviv_gem_object *etnaviv_obj)
26 {
27 	struct drm_device *dev = etnaviv_obj->base.dev;
28 	struct sg_table *sgt = etnaviv_obj->sgt;
29 
30 	/*
31 	 * For non-cached buffers, ensure the new pages are clean
32 	 * because display controller, GPU, etc. are not coherent.
33 	 */
34 	if (etnaviv_obj->flags & ETNA_BO_CACHE_MASK)
35 		dma_map_sg(dev->dev, sgt->sgl, sgt->nents, DMA_BIDIRECTIONAL);
36 }
37 
38 static void etnaviv_gem_scatterlist_unmap(struct etnaviv_gem_object *etnaviv_obj)
39 {
40 	struct drm_device *dev = etnaviv_obj->base.dev;
41 	struct sg_table *sgt = etnaviv_obj->sgt;
42 
43 	/*
44 	 * For non-cached buffers, ensure the new pages are clean
45 	 * because display controller, GPU, etc. are not coherent:
46 	 *
47 	 * WARNING: The DMA API does not support concurrent CPU
48 	 * and device access to the memory area.  With BIDIRECTIONAL,
49 	 * we will clean the cache lines which overlap the region,
50 	 * and invalidate all cache lines (partially) contained in
51 	 * the region.
52 	 *
53 	 * If you have dirty data in the overlapping cache lines,
54 	 * that will corrupt the GPU-written data.  If you have
55 	 * written into the remainder of the region, this can
56 	 * discard those writes.
57 	 */
58 	if (etnaviv_obj->flags & ETNA_BO_CACHE_MASK)
59 		dma_unmap_sg(dev->dev, sgt->sgl, sgt->nents, DMA_BIDIRECTIONAL);
60 }
61 
62 /* called with etnaviv_obj->lock held */
63 static int etnaviv_gem_shmem_get_pages(struct etnaviv_gem_object *etnaviv_obj)
64 {
65 	struct drm_device *dev = etnaviv_obj->base.dev;
66 	struct page **p = drm_gem_get_pages(&etnaviv_obj->base);
67 
68 	if (IS_ERR(p)) {
69 		dev_err(dev->dev, "could not get pages: %ld\n", PTR_ERR(p));
70 		return PTR_ERR(p);
71 	}
72 
73 	etnaviv_obj->pages = p;
74 
75 	return 0;
76 }
77 
78 static void put_pages(struct etnaviv_gem_object *etnaviv_obj)
79 {
80 	if (etnaviv_obj->sgt) {
81 		etnaviv_gem_scatterlist_unmap(etnaviv_obj);
82 		sg_free_table(etnaviv_obj->sgt);
83 		kfree(etnaviv_obj->sgt);
84 		etnaviv_obj->sgt = NULL;
85 	}
86 	if (etnaviv_obj->pages) {
87 		drm_gem_put_pages(&etnaviv_obj->base, etnaviv_obj->pages,
88 				  true, false);
89 
90 		etnaviv_obj->pages = NULL;
91 	}
92 }
93 
94 struct page **etnaviv_gem_get_pages(struct etnaviv_gem_object *etnaviv_obj)
95 {
96 	int ret;
97 
98 	lockdep_assert_held(&etnaviv_obj->lock);
99 
100 	if (!etnaviv_obj->pages) {
101 		ret = etnaviv_obj->ops->get_pages(etnaviv_obj);
102 		if (ret < 0)
103 			return ERR_PTR(ret);
104 	}
105 
106 	if (!etnaviv_obj->sgt) {
107 		struct drm_device *dev = etnaviv_obj->base.dev;
108 		int npages = etnaviv_obj->base.size >> PAGE_SHIFT;
109 		struct sg_table *sgt;
110 
111 		sgt = drm_prime_pages_to_sg(etnaviv_obj->pages, npages);
112 		if (IS_ERR(sgt)) {
113 			dev_err(dev->dev, "failed to allocate sgt: %ld\n",
114 				PTR_ERR(sgt));
115 			return ERR_CAST(sgt);
116 		}
117 
118 		etnaviv_obj->sgt = sgt;
119 
120 		etnaviv_gem_scatter_map(etnaviv_obj);
121 	}
122 
123 	return etnaviv_obj->pages;
124 }
125 
126 void etnaviv_gem_put_pages(struct etnaviv_gem_object *etnaviv_obj)
127 {
128 	lockdep_assert_held(&etnaviv_obj->lock);
129 	/* when we start tracking the pin count, then do something here */
130 }
131 
132 static int etnaviv_gem_mmap_obj(struct etnaviv_gem_object *etnaviv_obj,
133 		struct vm_area_struct *vma)
134 {
135 	pgprot_t vm_page_prot;
136 
137 	vma->vm_flags &= ~VM_PFNMAP;
138 	vma->vm_flags |= VM_MIXEDMAP;
139 
140 	vm_page_prot = vm_get_page_prot(vma->vm_flags);
141 
142 	if (etnaviv_obj->flags & ETNA_BO_WC) {
143 		vma->vm_page_prot = pgprot_writecombine(vm_page_prot);
144 	} else if (etnaviv_obj->flags & ETNA_BO_UNCACHED) {
145 		vma->vm_page_prot = pgprot_noncached(vm_page_prot);
146 	} else {
147 		/*
148 		 * Shunt off cached objs to shmem file so they have their own
149 		 * address_space (so unmap_mapping_range does what we want,
150 		 * in particular in the case of mmap'd dmabufs)
151 		 */
152 		fput(vma->vm_file);
153 		get_file(etnaviv_obj->base.filp);
154 		vma->vm_pgoff = 0;
155 		vma->vm_file  = etnaviv_obj->base.filp;
156 
157 		vma->vm_page_prot = vm_page_prot;
158 	}
159 
160 	return 0;
161 }
162 
163 int etnaviv_gem_mmap(struct file *filp, struct vm_area_struct *vma)
164 {
165 	struct etnaviv_gem_object *obj;
166 	int ret;
167 
168 	ret = drm_gem_mmap(filp, vma);
169 	if (ret) {
170 		DBG("mmap failed: %d", ret);
171 		return ret;
172 	}
173 
174 	obj = to_etnaviv_bo(vma->vm_private_data);
175 	return obj->ops->mmap(obj, vma);
176 }
177 
178 int etnaviv_gem_fault(struct vm_fault *vmf)
179 {
180 	struct vm_area_struct *vma = vmf->vma;
181 	struct drm_gem_object *obj = vma->vm_private_data;
182 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
183 	struct page **pages, *page;
184 	pgoff_t pgoff;
185 	int ret;
186 
187 	/*
188 	 * Make sure we don't parallel update on a fault, nor move or remove
189 	 * something from beneath our feet.  Note that vm_insert_page() is
190 	 * specifically coded to take care of this, so we don't have to.
191 	 */
192 	ret = mutex_lock_interruptible(&etnaviv_obj->lock);
193 	if (ret)
194 		goto out;
195 
196 	/* make sure we have pages attached now */
197 	pages = etnaviv_gem_get_pages(etnaviv_obj);
198 	mutex_unlock(&etnaviv_obj->lock);
199 
200 	if (IS_ERR(pages)) {
201 		ret = PTR_ERR(pages);
202 		goto out;
203 	}
204 
205 	/* We don't use vmf->pgoff since that has the fake offset: */
206 	pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
207 
208 	page = pages[pgoff];
209 
210 	VERB("Inserting %p pfn %lx, pa %lx", (void *)vmf->address,
211 	     page_to_pfn(page), page_to_pfn(page) << PAGE_SHIFT);
212 
213 	ret = vm_insert_page(vma, vmf->address, page);
214 
215 out:
216 	switch (ret) {
217 	case -EAGAIN:
218 	case 0:
219 	case -ERESTARTSYS:
220 	case -EINTR:
221 	case -EBUSY:
222 		/*
223 		 * EBUSY is ok: this just means that another thread
224 		 * already did the job.
225 		 */
226 		return VM_FAULT_NOPAGE;
227 	case -ENOMEM:
228 		return VM_FAULT_OOM;
229 	default:
230 		return VM_FAULT_SIGBUS;
231 	}
232 }
233 
234 int etnaviv_gem_mmap_offset(struct drm_gem_object *obj, u64 *offset)
235 {
236 	int ret;
237 
238 	/* Make it mmapable */
239 	ret = drm_gem_create_mmap_offset(obj);
240 	if (ret)
241 		dev_err(obj->dev->dev, "could not allocate mmap offset\n");
242 	else
243 		*offset = drm_vma_node_offset_addr(&obj->vma_node);
244 
245 	return ret;
246 }
247 
248 static struct etnaviv_vram_mapping *
249 etnaviv_gem_get_vram_mapping(struct etnaviv_gem_object *obj,
250 			     struct etnaviv_iommu *mmu)
251 {
252 	struct etnaviv_vram_mapping *mapping;
253 
254 	list_for_each_entry(mapping, &obj->vram_list, obj_node) {
255 		if (mapping->mmu == mmu)
256 			return mapping;
257 	}
258 
259 	return NULL;
260 }
261 
262 void etnaviv_gem_mapping_reference(struct etnaviv_vram_mapping *mapping)
263 {
264 	struct etnaviv_gem_object *etnaviv_obj = mapping->object;
265 
266 	drm_gem_object_reference(&etnaviv_obj->base);
267 
268 	mutex_lock(&etnaviv_obj->lock);
269 	WARN_ON(mapping->use == 0);
270 	mapping->use += 1;
271 	mutex_unlock(&etnaviv_obj->lock);
272 }
273 
274 void etnaviv_gem_mapping_unreference(struct etnaviv_vram_mapping *mapping)
275 {
276 	struct etnaviv_gem_object *etnaviv_obj = mapping->object;
277 
278 	mutex_lock(&etnaviv_obj->lock);
279 	WARN_ON(mapping->use == 0);
280 	mapping->use -= 1;
281 	mutex_unlock(&etnaviv_obj->lock);
282 
283 	drm_gem_object_unreference_unlocked(&etnaviv_obj->base);
284 }
285 
286 struct etnaviv_vram_mapping *etnaviv_gem_mapping_get(
287 	struct drm_gem_object *obj, struct etnaviv_gpu *gpu)
288 {
289 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
290 	struct etnaviv_vram_mapping *mapping;
291 	struct page **pages;
292 	int ret = 0;
293 
294 	mutex_lock(&etnaviv_obj->lock);
295 	mapping = etnaviv_gem_get_vram_mapping(etnaviv_obj, gpu->mmu);
296 	if (mapping) {
297 		/*
298 		 * Holding the object lock prevents the use count changing
299 		 * beneath us.  If the use count is zero, the MMU might be
300 		 * reaping this object, so take the lock and re-check that
301 		 * the MMU owns this mapping to close this race.
302 		 */
303 		if (mapping->use == 0) {
304 			mutex_lock(&gpu->mmu->lock);
305 			if (mapping->mmu == gpu->mmu)
306 				mapping->use += 1;
307 			else
308 				mapping = NULL;
309 			mutex_unlock(&gpu->mmu->lock);
310 			if (mapping)
311 				goto out;
312 		} else {
313 			mapping->use += 1;
314 			goto out;
315 		}
316 	}
317 
318 	pages = etnaviv_gem_get_pages(etnaviv_obj);
319 	if (IS_ERR(pages)) {
320 		ret = PTR_ERR(pages);
321 		goto out;
322 	}
323 
324 	/*
325 	 * See if we have a reaped vram mapping we can re-use before
326 	 * allocating a fresh mapping.
327 	 */
328 	mapping = etnaviv_gem_get_vram_mapping(etnaviv_obj, NULL);
329 	if (!mapping) {
330 		mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
331 		if (!mapping) {
332 			ret = -ENOMEM;
333 			goto out;
334 		}
335 
336 		INIT_LIST_HEAD(&mapping->scan_node);
337 		mapping->object = etnaviv_obj;
338 	} else {
339 		list_del(&mapping->obj_node);
340 	}
341 
342 	mapping->mmu = gpu->mmu;
343 	mapping->use = 1;
344 
345 	ret = etnaviv_iommu_map_gem(gpu->mmu, etnaviv_obj, gpu->memory_base,
346 				    mapping);
347 	if (ret < 0)
348 		kfree(mapping);
349 	else
350 		list_add_tail(&mapping->obj_node, &etnaviv_obj->vram_list);
351 
352 out:
353 	mutex_unlock(&etnaviv_obj->lock);
354 
355 	if (ret)
356 		return ERR_PTR(ret);
357 
358 	/* Take a reference on the object */
359 	drm_gem_object_reference(obj);
360 	return mapping;
361 }
362 
363 void *etnaviv_gem_vmap(struct drm_gem_object *obj)
364 {
365 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
366 
367 	if (etnaviv_obj->vaddr)
368 		return etnaviv_obj->vaddr;
369 
370 	mutex_lock(&etnaviv_obj->lock);
371 	/*
372 	 * Need to check again, as we might have raced with another thread
373 	 * while waiting for the mutex.
374 	 */
375 	if (!etnaviv_obj->vaddr)
376 		etnaviv_obj->vaddr = etnaviv_obj->ops->vmap(etnaviv_obj);
377 	mutex_unlock(&etnaviv_obj->lock);
378 
379 	return etnaviv_obj->vaddr;
380 }
381 
382 static void *etnaviv_gem_vmap_impl(struct etnaviv_gem_object *obj)
383 {
384 	struct page **pages;
385 
386 	lockdep_assert_held(&obj->lock);
387 
388 	pages = etnaviv_gem_get_pages(obj);
389 	if (IS_ERR(pages))
390 		return NULL;
391 
392 	return vmap(pages, obj->base.size >> PAGE_SHIFT,
393 			VM_MAP, pgprot_writecombine(PAGE_KERNEL));
394 }
395 
396 static inline enum dma_data_direction etnaviv_op_to_dma_dir(u32 op)
397 {
398 	if (op & ETNA_PREP_READ)
399 		return DMA_FROM_DEVICE;
400 	else if (op & ETNA_PREP_WRITE)
401 		return DMA_TO_DEVICE;
402 	else
403 		return DMA_BIDIRECTIONAL;
404 }
405 
406 int etnaviv_gem_cpu_prep(struct drm_gem_object *obj, u32 op,
407 		struct timespec *timeout)
408 {
409 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
410 	struct drm_device *dev = obj->dev;
411 	bool write = !!(op & ETNA_PREP_WRITE);
412 	unsigned long remain =
413 		op & ETNA_PREP_NOSYNC ? 0 : etnaviv_timeout_to_jiffies(timeout);
414 	long lret;
415 
416 	lret = reservation_object_wait_timeout_rcu(etnaviv_obj->resv,
417 						   write, true, remain);
418 	if (lret < 0)
419 		return lret;
420 	else if (lret == 0)
421 		return remain == 0 ? -EBUSY : -ETIMEDOUT;
422 
423 	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
424 		if (!etnaviv_obj->sgt) {
425 			void *ret;
426 
427 			mutex_lock(&etnaviv_obj->lock);
428 			ret = etnaviv_gem_get_pages(etnaviv_obj);
429 			mutex_unlock(&etnaviv_obj->lock);
430 			if (IS_ERR(ret))
431 				return PTR_ERR(ret);
432 		}
433 
434 		dma_sync_sg_for_cpu(dev->dev, etnaviv_obj->sgt->sgl,
435 				    etnaviv_obj->sgt->nents,
436 				    etnaviv_op_to_dma_dir(op));
437 		etnaviv_obj->last_cpu_prep_op = op;
438 	}
439 
440 	return 0;
441 }
442 
443 int etnaviv_gem_cpu_fini(struct drm_gem_object *obj)
444 {
445 	struct drm_device *dev = obj->dev;
446 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
447 
448 	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
449 		/* fini without a prep is almost certainly a userspace error */
450 		WARN_ON(etnaviv_obj->last_cpu_prep_op == 0);
451 		dma_sync_sg_for_device(dev->dev, etnaviv_obj->sgt->sgl,
452 			etnaviv_obj->sgt->nents,
453 			etnaviv_op_to_dma_dir(etnaviv_obj->last_cpu_prep_op));
454 		etnaviv_obj->last_cpu_prep_op = 0;
455 	}
456 
457 	return 0;
458 }
459 
460 int etnaviv_gem_wait_bo(struct etnaviv_gpu *gpu, struct drm_gem_object *obj,
461 	struct timespec *timeout)
462 {
463 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
464 
465 	return etnaviv_gpu_wait_obj_inactive(gpu, etnaviv_obj, timeout);
466 }
467 
468 #ifdef CONFIG_DEBUG_FS
469 static void etnaviv_gem_describe_fence(struct dma_fence *fence,
470 	const char *type, struct seq_file *m)
471 {
472 	if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags))
473 		seq_printf(m, "\t%9s: %s %s seq %u\n",
474 			   type,
475 			   fence->ops->get_driver_name(fence),
476 			   fence->ops->get_timeline_name(fence),
477 			   fence->seqno);
478 }
479 
480 static void etnaviv_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
481 {
482 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
483 	struct reservation_object *robj = etnaviv_obj->resv;
484 	struct reservation_object_list *fobj;
485 	struct dma_fence *fence;
486 	unsigned long off = drm_vma_node_start(&obj->vma_node);
487 
488 	seq_printf(m, "%08x: %c %2d (%2d) %08lx %p %zd\n",
489 			etnaviv_obj->flags, is_active(etnaviv_obj) ? 'A' : 'I',
490 			obj->name, kref_read(&obj->refcount),
491 			off, etnaviv_obj->vaddr, obj->size);
492 
493 	rcu_read_lock();
494 	fobj = rcu_dereference(robj->fence);
495 	if (fobj) {
496 		unsigned int i, shared_count = fobj->shared_count;
497 
498 		for (i = 0; i < shared_count; i++) {
499 			fence = rcu_dereference(fobj->shared[i]);
500 			etnaviv_gem_describe_fence(fence, "Shared", m);
501 		}
502 	}
503 
504 	fence = rcu_dereference(robj->fence_excl);
505 	if (fence)
506 		etnaviv_gem_describe_fence(fence, "Exclusive", m);
507 	rcu_read_unlock();
508 }
509 
510 void etnaviv_gem_describe_objects(struct etnaviv_drm_private *priv,
511 	struct seq_file *m)
512 {
513 	struct etnaviv_gem_object *etnaviv_obj;
514 	int count = 0;
515 	size_t size = 0;
516 
517 	mutex_lock(&priv->gem_lock);
518 	list_for_each_entry(etnaviv_obj, &priv->gem_list, gem_node) {
519 		struct drm_gem_object *obj = &etnaviv_obj->base;
520 
521 		seq_puts(m, "   ");
522 		etnaviv_gem_describe(obj, m);
523 		count++;
524 		size += obj->size;
525 	}
526 	mutex_unlock(&priv->gem_lock);
527 
528 	seq_printf(m, "Total %d objects, %zu bytes\n", count, size);
529 }
530 #endif
531 
532 static void etnaviv_gem_shmem_release(struct etnaviv_gem_object *etnaviv_obj)
533 {
534 	vunmap(etnaviv_obj->vaddr);
535 	put_pages(etnaviv_obj);
536 }
537 
538 static const struct etnaviv_gem_ops etnaviv_gem_shmem_ops = {
539 	.get_pages = etnaviv_gem_shmem_get_pages,
540 	.release = etnaviv_gem_shmem_release,
541 	.vmap = etnaviv_gem_vmap_impl,
542 	.mmap = etnaviv_gem_mmap_obj,
543 };
544 
545 void etnaviv_gem_free_object(struct drm_gem_object *obj)
546 {
547 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
548 	struct etnaviv_vram_mapping *mapping, *tmp;
549 
550 	/* object should not be active */
551 	WARN_ON(is_active(etnaviv_obj));
552 
553 	list_del(&etnaviv_obj->gem_node);
554 
555 	list_for_each_entry_safe(mapping, tmp, &etnaviv_obj->vram_list,
556 				 obj_node) {
557 		struct etnaviv_iommu *mmu = mapping->mmu;
558 
559 		WARN_ON(mapping->use);
560 
561 		if (mmu)
562 			etnaviv_iommu_unmap_gem(mmu, mapping);
563 
564 		list_del(&mapping->obj_node);
565 		kfree(mapping);
566 	}
567 
568 	drm_gem_free_mmap_offset(obj);
569 	etnaviv_obj->ops->release(etnaviv_obj);
570 	if (etnaviv_obj->resv == &etnaviv_obj->_resv)
571 		reservation_object_fini(&etnaviv_obj->_resv);
572 	drm_gem_object_release(obj);
573 
574 	kfree(etnaviv_obj);
575 }
576 
577 int etnaviv_gem_obj_add(struct drm_device *dev, struct drm_gem_object *obj)
578 {
579 	struct etnaviv_drm_private *priv = dev->dev_private;
580 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
581 
582 	mutex_lock(&priv->gem_lock);
583 	list_add_tail(&etnaviv_obj->gem_node, &priv->gem_list);
584 	mutex_unlock(&priv->gem_lock);
585 
586 	return 0;
587 }
588 
589 static int etnaviv_gem_new_impl(struct drm_device *dev, u32 size, u32 flags,
590 	struct reservation_object *robj, const struct etnaviv_gem_ops *ops,
591 	struct drm_gem_object **obj)
592 {
593 	struct etnaviv_gem_object *etnaviv_obj;
594 	unsigned sz = sizeof(*etnaviv_obj);
595 	bool valid = true;
596 
597 	/* validate flags */
598 	switch (flags & ETNA_BO_CACHE_MASK) {
599 	case ETNA_BO_UNCACHED:
600 	case ETNA_BO_CACHED:
601 	case ETNA_BO_WC:
602 		break;
603 	default:
604 		valid = false;
605 	}
606 
607 	if (!valid) {
608 		dev_err(dev->dev, "invalid cache flag: %x\n",
609 			(flags & ETNA_BO_CACHE_MASK));
610 		return -EINVAL;
611 	}
612 
613 	etnaviv_obj = kzalloc(sz, GFP_KERNEL);
614 	if (!etnaviv_obj)
615 		return -ENOMEM;
616 
617 	etnaviv_obj->flags = flags;
618 	etnaviv_obj->ops = ops;
619 	if (robj) {
620 		etnaviv_obj->resv = robj;
621 	} else {
622 		etnaviv_obj->resv = &etnaviv_obj->_resv;
623 		reservation_object_init(&etnaviv_obj->_resv);
624 	}
625 
626 	mutex_init(&etnaviv_obj->lock);
627 	INIT_LIST_HEAD(&etnaviv_obj->vram_list);
628 
629 	*obj = &etnaviv_obj->base;
630 
631 	return 0;
632 }
633 
634 static struct drm_gem_object *__etnaviv_gem_new(struct drm_device *dev,
635 		u32 size, u32 flags)
636 {
637 	struct drm_gem_object *obj = NULL;
638 	int ret;
639 
640 	size = PAGE_ALIGN(size);
641 
642 	ret = etnaviv_gem_new_impl(dev, size, flags, NULL,
643 				   &etnaviv_gem_shmem_ops, &obj);
644 	if (ret)
645 		goto fail;
646 
647 	ret = drm_gem_object_init(dev, obj, size);
648 	if (ret == 0) {
649 		struct address_space *mapping;
650 
651 		/*
652 		 * Our buffers are kept pinned, so allocating them
653 		 * from the MOVABLE zone is a really bad idea, and
654 		 * conflicts with CMA.  See coments above new_inode()
655 		 * why this is required _and_ expected if you're
656 		 * going to pin these pages.
657 		 */
658 		mapping = obj->filp->f_mapping;
659 		mapping_set_gfp_mask(mapping, GFP_HIGHUSER);
660 	}
661 
662 	if (ret)
663 		goto fail;
664 
665 	return obj;
666 
667 fail:
668 	drm_gem_object_unreference_unlocked(obj);
669 	return ERR_PTR(ret);
670 }
671 
672 /* convenience method to construct a GEM buffer object, and userspace handle */
673 int etnaviv_gem_new_handle(struct drm_device *dev, struct drm_file *file,
674 		u32 size, u32 flags, u32 *handle)
675 {
676 	struct drm_gem_object *obj;
677 	int ret;
678 
679 	obj = __etnaviv_gem_new(dev, size, flags);
680 	if (IS_ERR(obj))
681 		return PTR_ERR(obj);
682 
683 	ret = etnaviv_gem_obj_add(dev, obj);
684 	if (ret < 0) {
685 		drm_gem_object_unreference_unlocked(obj);
686 		return ret;
687 	}
688 
689 	ret = drm_gem_handle_create(file, obj, handle);
690 
691 	/* drop reference from allocate - handle holds it now */
692 	drm_gem_object_unreference_unlocked(obj);
693 
694 	return ret;
695 }
696 
697 struct drm_gem_object *etnaviv_gem_new(struct drm_device *dev,
698 		u32 size, u32 flags)
699 {
700 	struct drm_gem_object *obj;
701 	int ret;
702 
703 	obj = __etnaviv_gem_new(dev, size, flags);
704 	if (IS_ERR(obj))
705 		return obj;
706 
707 	ret = etnaviv_gem_obj_add(dev, obj);
708 	if (ret < 0) {
709 		drm_gem_object_unreference_unlocked(obj);
710 		return ERR_PTR(ret);
711 	}
712 
713 	return obj;
714 }
715 
716 int etnaviv_gem_new_private(struct drm_device *dev, size_t size, u32 flags,
717 	struct reservation_object *robj, const struct etnaviv_gem_ops *ops,
718 	struct etnaviv_gem_object **res)
719 {
720 	struct drm_gem_object *obj;
721 	int ret;
722 
723 	ret = etnaviv_gem_new_impl(dev, size, flags, robj, ops, &obj);
724 	if (ret)
725 		return ret;
726 
727 	drm_gem_private_object_init(dev, obj, size);
728 
729 	*res = to_etnaviv_bo(obj);
730 
731 	return 0;
732 }
733 
734 struct get_pages_work {
735 	struct work_struct work;
736 	struct mm_struct *mm;
737 	struct task_struct *task;
738 	struct etnaviv_gem_object *etnaviv_obj;
739 };
740 
741 static struct page **etnaviv_gem_userptr_do_get_pages(
742 	struct etnaviv_gem_object *etnaviv_obj, struct mm_struct *mm, struct task_struct *task)
743 {
744 	int ret = 0, pinned, npages = etnaviv_obj->base.size >> PAGE_SHIFT;
745 	struct page **pvec;
746 	uintptr_t ptr;
747 	unsigned int flags = 0;
748 
749 	pvec = drm_malloc_ab(npages, sizeof(struct page *));
750 	if (!pvec)
751 		return ERR_PTR(-ENOMEM);
752 
753 	if (!etnaviv_obj->userptr.ro)
754 		flags |= FOLL_WRITE;
755 
756 	pinned = 0;
757 	ptr = etnaviv_obj->userptr.ptr;
758 
759 	down_read(&mm->mmap_sem);
760 	while (pinned < npages) {
761 		ret = get_user_pages_remote(task, mm, ptr, npages - pinned,
762 					    flags, pvec + pinned, NULL, NULL);
763 		if (ret < 0)
764 			break;
765 
766 		ptr += ret * PAGE_SIZE;
767 		pinned += ret;
768 	}
769 	up_read(&mm->mmap_sem);
770 
771 	if (ret < 0) {
772 		release_pages(pvec, pinned, 0);
773 		drm_free_large(pvec);
774 		return ERR_PTR(ret);
775 	}
776 
777 	return pvec;
778 }
779 
780 static void __etnaviv_gem_userptr_get_pages(struct work_struct *_work)
781 {
782 	struct get_pages_work *work = container_of(_work, typeof(*work), work);
783 	struct etnaviv_gem_object *etnaviv_obj = work->etnaviv_obj;
784 	struct page **pvec;
785 
786 	pvec = etnaviv_gem_userptr_do_get_pages(etnaviv_obj, work->mm, work->task);
787 
788 	mutex_lock(&etnaviv_obj->lock);
789 	if (IS_ERR(pvec)) {
790 		etnaviv_obj->userptr.work = ERR_CAST(pvec);
791 	} else {
792 		etnaviv_obj->userptr.work = NULL;
793 		etnaviv_obj->pages = pvec;
794 	}
795 
796 	mutex_unlock(&etnaviv_obj->lock);
797 	drm_gem_object_unreference_unlocked(&etnaviv_obj->base);
798 
799 	mmput(work->mm);
800 	put_task_struct(work->task);
801 	kfree(work);
802 }
803 
804 static int etnaviv_gem_userptr_get_pages(struct etnaviv_gem_object *etnaviv_obj)
805 {
806 	struct page **pvec = NULL;
807 	struct get_pages_work *work;
808 	struct mm_struct *mm;
809 	int ret, pinned, npages = etnaviv_obj->base.size >> PAGE_SHIFT;
810 
811 	if (etnaviv_obj->userptr.work) {
812 		if (IS_ERR(etnaviv_obj->userptr.work)) {
813 			ret = PTR_ERR(etnaviv_obj->userptr.work);
814 			etnaviv_obj->userptr.work = NULL;
815 		} else {
816 			ret = -EAGAIN;
817 		}
818 		return ret;
819 	}
820 
821 	mm = get_task_mm(etnaviv_obj->userptr.task);
822 	pinned = 0;
823 	if (mm == current->mm) {
824 		pvec = drm_malloc_ab(npages, sizeof(struct page *));
825 		if (!pvec) {
826 			mmput(mm);
827 			return -ENOMEM;
828 		}
829 
830 		pinned = __get_user_pages_fast(etnaviv_obj->userptr.ptr, npages,
831 					       !etnaviv_obj->userptr.ro, pvec);
832 		if (pinned < 0) {
833 			drm_free_large(pvec);
834 			mmput(mm);
835 			return pinned;
836 		}
837 
838 		if (pinned == npages) {
839 			etnaviv_obj->pages = pvec;
840 			mmput(mm);
841 			return 0;
842 		}
843 	}
844 
845 	release_pages(pvec, pinned, 0);
846 	drm_free_large(pvec);
847 
848 	work = kmalloc(sizeof(*work), GFP_KERNEL);
849 	if (!work) {
850 		mmput(mm);
851 		return -ENOMEM;
852 	}
853 
854 	get_task_struct(current);
855 	drm_gem_object_reference(&etnaviv_obj->base);
856 
857 	work->mm = mm;
858 	work->task = current;
859 	work->etnaviv_obj = etnaviv_obj;
860 
861 	etnaviv_obj->userptr.work = &work->work;
862 	INIT_WORK(&work->work, __etnaviv_gem_userptr_get_pages);
863 
864 	etnaviv_queue_work(etnaviv_obj->base.dev, &work->work);
865 
866 	return -EAGAIN;
867 }
868 
869 static void etnaviv_gem_userptr_release(struct etnaviv_gem_object *etnaviv_obj)
870 {
871 	if (etnaviv_obj->sgt) {
872 		etnaviv_gem_scatterlist_unmap(etnaviv_obj);
873 		sg_free_table(etnaviv_obj->sgt);
874 		kfree(etnaviv_obj->sgt);
875 	}
876 	if (etnaviv_obj->pages) {
877 		int npages = etnaviv_obj->base.size >> PAGE_SHIFT;
878 
879 		release_pages(etnaviv_obj->pages, npages, 0);
880 		drm_free_large(etnaviv_obj->pages);
881 	}
882 	put_task_struct(etnaviv_obj->userptr.task);
883 }
884 
885 static int etnaviv_gem_userptr_mmap_obj(struct etnaviv_gem_object *etnaviv_obj,
886 		struct vm_area_struct *vma)
887 {
888 	return -EINVAL;
889 }
890 
891 static const struct etnaviv_gem_ops etnaviv_gem_userptr_ops = {
892 	.get_pages = etnaviv_gem_userptr_get_pages,
893 	.release = etnaviv_gem_userptr_release,
894 	.vmap = etnaviv_gem_vmap_impl,
895 	.mmap = etnaviv_gem_userptr_mmap_obj,
896 };
897 
898 int etnaviv_gem_new_userptr(struct drm_device *dev, struct drm_file *file,
899 	uintptr_t ptr, u32 size, u32 flags, u32 *handle)
900 {
901 	struct etnaviv_gem_object *etnaviv_obj;
902 	int ret;
903 
904 	ret = etnaviv_gem_new_private(dev, size, ETNA_BO_CACHED, NULL,
905 				      &etnaviv_gem_userptr_ops, &etnaviv_obj);
906 	if (ret)
907 		return ret;
908 
909 	etnaviv_obj->userptr.ptr = ptr;
910 	etnaviv_obj->userptr.task = current;
911 	etnaviv_obj->userptr.ro = !(flags & ETNA_USERPTR_WRITE);
912 	get_task_struct(current);
913 
914 	ret = etnaviv_gem_obj_add(dev, &etnaviv_obj->base);
915 	if (ret)
916 		goto unreference;
917 
918 	ret = drm_gem_handle_create(file, &etnaviv_obj->base, handle);
919 unreference:
920 	/* drop reference from allocate - handle holds it now */
921 	drm_gem_object_unreference_unlocked(&etnaviv_obj->base);
922 	return ret;
923 }
924