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 drm_gem_object *obj,
133 		struct vm_area_struct *vma)
134 {
135 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
136 	pgprot_t vm_page_prot;
137 
138 	vma->vm_flags &= ~VM_PFNMAP;
139 	vma->vm_flags |= VM_MIXEDMAP;
140 
141 	vm_page_prot = vm_get_page_prot(vma->vm_flags);
142 
143 	if (etnaviv_obj->flags & ETNA_BO_WC) {
144 		vma->vm_page_prot = pgprot_writecombine(vm_page_prot);
145 	} else if (etnaviv_obj->flags & ETNA_BO_UNCACHED) {
146 		vma->vm_page_prot = pgprot_noncached(vm_page_prot);
147 	} else {
148 		/*
149 		 * Shunt off cached objs to shmem file so they have their own
150 		 * address_space (so unmap_mapping_range does what we want,
151 		 * in particular in the case of mmap'd dmabufs)
152 		 */
153 		fput(vma->vm_file);
154 		get_file(obj->filp);
155 		vma->vm_pgoff = 0;
156 		vma->vm_file  = obj->filp;
157 
158 		vma->vm_page_prot = vm_page_prot;
159 	}
160 
161 	return 0;
162 }
163 
164 int etnaviv_gem_mmap(struct file *filp, struct vm_area_struct *vma)
165 {
166 	struct etnaviv_gem_object *obj;
167 	int ret;
168 
169 	ret = drm_gem_mmap(filp, vma);
170 	if (ret) {
171 		DBG("mmap failed: %d", ret);
172 		return ret;
173 	}
174 
175 	obj = to_etnaviv_bo(vma->vm_private_data);
176 	return etnaviv_gem_mmap_obj(vma->vm_private_data, vma);
177 }
178 
179 int etnaviv_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
180 {
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 = ((unsigned long)vmf->virtual_address -
207 			vma->vm_start) >> PAGE_SHIFT;
208 
209 	page = pages[pgoff];
210 
211 	VERB("Inserting %p pfn %lx, pa %lx", vmf->virtual_address,
212 	     page_to_pfn(page), page_to_pfn(page) << PAGE_SHIFT);
213 
214 	ret = vm_insert_page(vma, (unsigned long)vmf->virtual_address, page);
215 
216 out:
217 	switch (ret) {
218 	case -EAGAIN:
219 	case 0:
220 	case -ERESTARTSYS:
221 	case -EINTR:
222 	case -EBUSY:
223 		/*
224 		 * EBUSY is ok: this just means that another thread
225 		 * already did the job.
226 		 */
227 		return VM_FAULT_NOPAGE;
228 	case -ENOMEM:
229 		return VM_FAULT_OOM;
230 	default:
231 		return VM_FAULT_SIGBUS;
232 	}
233 }
234 
235 int etnaviv_gem_mmap_offset(struct drm_gem_object *obj, u64 *offset)
236 {
237 	int ret;
238 
239 	/* Make it mmapable */
240 	ret = drm_gem_create_mmap_offset(obj);
241 	if (ret)
242 		dev_err(obj->dev->dev, "could not allocate mmap offset\n");
243 	else
244 		*offset = drm_vma_node_offset_addr(&obj->vma_node);
245 
246 	return ret;
247 }
248 
249 static struct etnaviv_vram_mapping *
250 etnaviv_gem_get_vram_mapping(struct etnaviv_gem_object *obj,
251 			     struct etnaviv_iommu *mmu)
252 {
253 	struct etnaviv_vram_mapping *mapping;
254 
255 	list_for_each_entry(mapping, &obj->vram_list, obj_node) {
256 		if (mapping->mmu == mmu)
257 			return mapping;
258 	}
259 
260 	return NULL;
261 }
262 
263 int etnaviv_gem_get_iova(struct etnaviv_gpu *gpu,
264 	struct drm_gem_object *obj, u32 *iova)
265 {
266 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
267 	struct etnaviv_vram_mapping *mapping;
268 	struct page **pages;
269 	int ret = 0;
270 
271 	mutex_lock(&etnaviv_obj->lock);
272 	mapping = etnaviv_gem_get_vram_mapping(etnaviv_obj, gpu->mmu);
273 	if (mapping) {
274 		/*
275 		 * Holding the object lock prevents the use count changing
276 		 * beneath us.  If the use count is zero, the MMU might be
277 		 * reaping this object, so take the lock and re-check that
278 		 * the MMU owns this mapping to close this race.
279 		 */
280 		if (mapping->use == 0) {
281 			mutex_lock(&gpu->mmu->lock);
282 			if (mapping->mmu == gpu->mmu)
283 				mapping->use += 1;
284 			else
285 				mapping = NULL;
286 			mutex_unlock(&gpu->mmu->lock);
287 			if (mapping)
288 				goto out;
289 		} else {
290 			mapping->use += 1;
291 			goto out;
292 		}
293 	}
294 
295 	pages = etnaviv_gem_get_pages(etnaviv_obj);
296 	if (IS_ERR(pages)) {
297 		ret = PTR_ERR(pages);
298 		goto out;
299 	}
300 
301 	/*
302 	 * See if we have a reaped vram mapping we can re-use before
303 	 * allocating a fresh mapping.
304 	 */
305 	mapping = etnaviv_gem_get_vram_mapping(etnaviv_obj, NULL);
306 	if (!mapping) {
307 		mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
308 		if (!mapping) {
309 			ret = -ENOMEM;
310 			goto out;
311 		}
312 
313 		INIT_LIST_HEAD(&mapping->scan_node);
314 		mapping->object = etnaviv_obj;
315 	} else {
316 		list_del(&mapping->obj_node);
317 	}
318 
319 	mapping->mmu = gpu->mmu;
320 	mapping->use = 1;
321 
322 	ret = etnaviv_iommu_map_gem(gpu->mmu, etnaviv_obj, gpu->memory_base,
323 				    mapping);
324 	if (ret < 0)
325 		kfree(mapping);
326 	else
327 		list_add_tail(&mapping->obj_node, &etnaviv_obj->vram_list);
328 
329 out:
330 	mutex_unlock(&etnaviv_obj->lock);
331 
332 	if (!ret) {
333 		/* Take a reference on the object */
334 		drm_gem_object_reference(obj);
335 		*iova = mapping->iova;
336 	}
337 
338 	return ret;
339 }
340 
341 void etnaviv_gem_put_iova(struct etnaviv_gpu *gpu, struct drm_gem_object *obj)
342 {
343 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
344 	struct etnaviv_vram_mapping *mapping;
345 
346 	mutex_lock(&etnaviv_obj->lock);
347 	mapping = etnaviv_gem_get_vram_mapping(etnaviv_obj, gpu->mmu);
348 
349 	WARN_ON(mapping->use == 0);
350 	mapping->use -= 1;
351 	mutex_unlock(&etnaviv_obj->lock);
352 
353 	drm_gem_object_unreference_unlocked(obj);
354 }
355 
356 void *etnaviv_gem_vmap(struct drm_gem_object *obj)
357 {
358 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
359 
360 	if (etnaviv_obj->vaddr)
361 		return etnaviv_obj->vaddr;
362 
363 	mutex_lock(&etnaviv_obj->lock);
364 	/*
365 	 * Need to check again, as we might have raced with another thread
366 	 * while waiting for the mutex.
367 	 */
368 	if (!etnaviv_obj->vaddr)
369 		etnaviv_obj->vaddr = etnaviv_obj->ops->vmap(etnaviv_obj);
370 	mutex_unlock(&etnaviv_obj->lock);
371 
372 	return etnaviv_obj->vaddr;
373 }
374 
375 static void *etnaviv_gem_vmap_impl(struct etnaviv_gem_object *obj)
376 {
377 	struct page **pages;
378 
379 	lockdep_assert_held(&obj->lock);
380 
381 	pages = etnaviv_gem_get_pages(obj);
382 	if (IS_ERR(pages))
383 		return NULL;
384 
385 	return vmap(pages, obj->base.size >> PAGE_SHIFT,
386 			VM_MAP, pgprot_writecombine(PAGE_KERNEL));
387 }
388 
389 static inline enum dma_data_direction etnaviv_op_to_dma_dir(u32 op)
390 {
391 	if (op & ETNA_PREP_READ)
392 		return DMA_FROM_DEVICE;
393 	else if (op & ETNA_PREP_WRITE)
394 		return DMA_TO_DEVICE;
395 	else
396 		return DMA_BIDIRECTIONAL;
397 }
398 
399 int etnaviv_gem_cpu_prep(struct drm_gem_object *obj, u32 op,
400 		struct timespec *timeout)
401 {
402 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
403 	struct drm_device *dev = obj->dev;
404 	bool write = !!(op & ETNA_PREP_WRITE);
405 	int ret;
406 
407 	if (op & ETNA_PREP_NOSYNC) {
408 		if (!reservation_object_test_signaled_rcu(etnaviv_obj->resv,
409 							  write))
410 			return -EBUSY;
411 	} else {
412 		unsigned long remain = etnaviv_timeout_to_jiffies(timeout);
413 
414 		ret = reservation_object_wait_timeout_rcu(etnaviv_obj->resv,
415 							  write, true, remain);
416 		if (ret <= 0)
417 			return ret == 0 ? -ETIMEDOUT : ret;
418 	}
419 
420 	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
421 		if (!etnaviv_obj->sgt) {
422 			void *ret;
423 
424 			mutex_lock(&etnaviv_obj->lock);
425 			ret = etnaviv_gem_get_pages(etnaviv_obj);
426 			mutex_unlock(&etnaviv_obj->lock);
427 			if (IS_ERR(ret))
428 				return PTR_ERR(ret);
429 		}
430 
431 		dma_sync_sg_for_cpu(dev->dev, etnaviv_obj->sgt->sgl,
432 				    etnaviv_obj->sgt->nents,
433 				    etnaviv_op_to_dma_dir(op));
434 		etnaviv_obj->last_cpu_prep_op = op;
435 	}
436 
437 	return 0;
438 }
439 
440 int etnaviv_gem_cpu_fini(struct drm_gem_object *obj)
441 {
442 	struct drm_device *dev = obj->dev;
443 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
444 
445 	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
446 		/* fini without a prep is almost certainly a userspace error */
447 		WARN_ON(etnaviv_obj->last_cpu_prep_op == 0);
448 		dma_sync_sg_for_device(dev->dev, etnaviv_obj->sgt->sgl,
449 			etnaviv_obj->sgt->nents,
450 			etnaviv_op_to_dma_dir(etnaviv_obj->last_cpu_prep_op));
451 		etnaviv_obj->last_cpu_prep_op = 0;
452 	}
453 
454 	return 0;
455 }
456 
457 int etnaviv_gem_wait_bo(struct etnaviv_gpu *gpu, struct drm_gem_object *obj,
458 	struct timespec *timeout)
459 {
460 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
461 
462 	return etnaviv_gpu_wait_obj_inactive(gpu, etnaviv_obj, timeout);
463 }
464 
465 #ifdef CONFIG_DEBUG_FS
466 static void etnaviv_gem_describe_fence(struct fence *fence,
467 	const char *type, struct seq_file *m)
468 {
469 	if (!test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags))
470 		seq_printf(m, "\t%9s: %s %s seq %u\n",
471 			   type,
472 			   fence->ops->get_driver_name(fence),
473 			   fence->ops->get_timeline_name(fence),
474 			   fence->seqno);
475 }
476 
477 static void etnaviv_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
478 {
479 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
480 	struct reservation_object *robj = etnaviv_obj->resv;
481 	struct reservation_object_list *fobj;
482 	struct fence *fence;
483 	unsigned long off = drm_vma_node_start(&obj->vma_node);
484 
485 	seq_printf(m, "%08x: %c %2d (%2d) %08lx %p %zd\n",
486 			etnaviv_obj->flags, is_active(etnaviv_obj) ? 'A' : 'I',
487 			obj->name, obj->refcount.refcount.counter,
488 			off, etnaviv_obj->vaddr, obj->size);
489 
490 	rcu_read_lock();
491 	fobj = rcu_dereference(robj->fence);
492 	if (fobj) {
493 		unsigned int i, shared_count = fobj->shared_count;
494 
495 		for (i = 0; i < shared_count; i++) {
496 			fence = rcu_dereference(fobj->shared[i]);
497 			etnaviv_gem_describe_fence(fence, "Shared", m);
498 		}
499 	}
500 
501 	fence = rcu_dereference(robj->fence_excl);
502 	if (fence)
503 		etnaviv_gem_describe_fence(fence, "Exclusive", m);
504 	rcu_read_unlock();
505 }
506 
507 void etnaviv_gem_describe_objects(struct etnaviv_drm_private *priv,
508 	struct seq_file *m)
509 {
510 	struct etnaviv_gem_object *etnaviv_obj;
511 	int count = 0;
512 	size_t size = 0;
513 
514 	mutex_lock(&priv->gem_lock);
515 	list_for_each_entry(etnaviv_obj, &priv->gem_list, gem_node) {
516 		struct drm_gem_object *obj = &etnaviv_obj->base;
517 
518 		seq_puts(m, "   ");
519 		etnaviv_gem_describe(obj, m);
520 		count++;
521 		size += obj->size;
522 	}
523 	mutex_unlock(&priv->gem_lock);
524 
525 	seq_printf(m, "Total %d objects, %zu bytes\n", count, size);
526 }
527 #endif
528 
529 static void etnaviv_gem_shmem_release(struct etnaviv_gem_object *etnaviv_obj)
530 {
531 	if (etnaviv_obj->vaddr)
532 		vunmap(etnaviv_obj->vaddr);
533 	put_pages(etnaviv_obj);
534 }
535 
536 static const struct etnaviv_gem_ops etnaviv_gem_shmem_ops = {
537 	.get_pages = etnaviv_gem_shmem_get_pages,
538 	.release = etnaviv_gem_shmem_release,
539 	.vmap = etnaviv_gem_vmap_impl,
540 };
541 
542 void etnaviv_gem_free_object(struct drm_gem_object *obj)
543 {
544 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
545 	struct etnaviv_vram_mapping *mapping, *tmp;
546 
547 	/* object should not be active */
548 	WARN_ON(is_active(etnaviv_obj));
549 
550 	list_del(&etnaviv_obj->gem_node);
551 
552 	list_for_each_entry_safe(mapping, tmp, &etnaviv_obj->vram_list,
553 				 obj_node) {
554 		struct etnaviv_iommu *mmu = mapping->mmu;
555 
556 		WARN_ON(mapping->use);
557 
558 		if (mmu)
559 			etnaviv_iommu_unmap_gem(mmu, mapping);
560 
561 		list_del(&mapping->obj_node);
562 		kfree(mapping);
563 	}
564 
565 	drm_gem_free_mmap_offset(obj);
566 	etnaviv_obj->ops->release(etnaviv_obj);
567 	if (etnaviv_obj->resv == &etnaviv_obj->_resv)
568 		reservation_object_fini(&etnaviv_obj->_resv);
569 	drm_gem_object_release(obj);
570 
571 	kfree(etnaviv_obj);
572 }
573 
574 int etnaviv_gem_obj_add(struct drm_device *dev, struct drm_gem_object *obj)
575 {
576 	struct etnaviv_drm_private *priv = dev->dev_private;
577 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
578 
579 	mutex_lock(&priv->gem_lock);
580 	list_add_tail(&etnaviv_obj->gem_node, &priv->gem_list);
581 	mutex_unlock(&priv->gem_lock);
582 
583 	return 0;
584 }
585 
586 static int etnaviv_gem_new_impl(struct drm_device *dev, u32 size, u32 flags,
587 	struct reservation_object *robj, const struct etnaviv_gem_ops *ops,
588 	struct drm_gem_object **obj)
589 {
590 	struct etnaviv_gem_object *etnaviv_obj;
591 	unsigned sz = sizeof(*etnaviv_obj);
592 	bool valid = true;
593 
594 	/* validate flags */
595 	switch (flags & ETNA_BO_CACHE_MASK) {
596 	case ETNA_BO_UNCACHED:
597 	case ETNA_BO_CACHED:
598 	case ETNA_BO_WC:
599 		break;
600 	default:
601 		valid = false;
602 	}
603 
604 	if (!valid) {
605 		dev_err(dev->dev, "invalid cache flag: %x\n",
606 			(flags & ETNA_BO_CACHE_MASK));
607 		return -EINVAL;
608 	}
609 
610 	etnaviv_obj = kzalloc(sz, GFP_KERNEL);
611 	if (!etnaviv_obj)
612 		return -ENOMEM;
613 
614 	etnaviv_obj->flags = flags;
615 	etnaviv_obj->ops = ops;
616 	if (robj) {
617 		etnaviv_obj->resv = robj;
618 	} else {
619 		etnaviv_obj->resv = &etnaviv_obj->_resv;
620 		reservation_object_init(&etnaviv_obj->_resv);
621 	}
622 
623 	mutex_init(&etnaviv_obj->lock);
624 	INIT_LIST_HEAD(&etnaviv_obj->vram_list);
625 
626 	*obj = &etnaviv_obj->base;
627 
628 	return 0;
629 }
630 
631 static struct drm_gem_object *__etnaviv_gem_new(struct drm_device *dev,
632 		u32 size, u32 flags)
633 {
634 	struct drm_gem_object *obj = NULL;
635 	int ret;
636 
637 	size = PAGE_ALIGN(size);
638 
639 	ret = etnaviv_gem_new_impl(dev, size, flags, NULL,
640 				   &etnaviv_gem_shmem_ops, &obj);
641 	if (ret)
642 		goto fail;
643 
644 	ret = drm_gem_object_init(dev, obj, size);
645 	if (ret == 0) {
646 		struct address_space *mapping;
647 
648 		/*
649 		 * Our buffers are kept pinned, so allocating them
650 		 * from the MOVABLE zone is a really bad idea, and
651 		 * conflicts with CMA.  See coments above new_inode()
652 		 * why this is required _and_ expected if you're
653 		 * going to pin these pages.
654 		 */
655 		mapping = file_inode(obj->filp)->i_mapping;
656 		mapping_set_gfp_mask(mapping, GFP_HIGHUSER);
657 	}
658 
659 	if (ret)
660 		goto fail;
661 
662 	return obj;
663 
664 fail:
665 	if (obj)
666 		drm_gem_object_unreference_unlocked(obj);
667 
668 	return ERR_PTR(ret);
669 }
670 
671 /* convenience method to construct a GEM buffer object, and userspace handle */
672 int etnaviv_gem_new_handle(struct drm_device *dev, struct drm_file *file,
673 		u32 size, u32 flags, u32 *handle)
674 {
675 	struct drm_gem_object *obj;
676 	int ret;
677 
678 	obj = __etnaviv_gem_new(dev, size, flags);
679 	if (IS_ERR(obj))
680 		return PTR_ERR(obj);
681 
682 	ret = etnaviv_gem_obj_add(dev, obj);
683 	if (ret < 0) {
684 		drm_gem_object_unreference_unlocked(obj);
685 		return ret;
686 	}
687 
688 	ret = drm_gem_handle_create(file, obj, handle);
689 
690 	/* drop reference from allocate - handle holds it now */
691 	drm_gem_object_unreference_unlocked(obj);
692 
693 	return ret;
694 }
695 
696 struct drm_gem_object *etnaviv_gem_new(struct drm_device *dev,
697 		u32 size, u32 flags)
698 {
699 	struct drm_gem_object *obj;
700 	int ret;
701 
702 	obj = __etnaviv_gem_new(dev, size, flags);
703 	if (IS_ERR(obj))
704 		return obj;
705 
706 	ret = etnaviv_gem_obj_add(dev, obj);
707 	if (ret < 0) {
708 		drm_gem_object_unreference_unlocked(obj);
709 		return ERR_PTR(ret);
710 	}
711 
712 	return obj;
713 }
714 
715 int etnaviv_gem_new_private(struct drm_device *dev, size_t size, u32 flags,
716 	struct reservation_object *robj, const struct etnaviv_gem_ops *ops,
717 	struct etnaviv_gem_object **res)
718 {
719 	struct drm_gem_object *obj;
720 	int ret;
721 
722 	ret = etnaviv_gem_new_impl(dev, size, flags, robj, ops, &obj);
723 	if (ret)
724 		return ret;
725 
726 	drm_gem_private_object_init(dev, obj, size);
727 
728 	*res = to_etnaviv_bo(obj);
729 
730 	return 0;
731 }
732 
733 struct get_pages_work {
734 	struct work_struct work;
735 	struct mm_struct *mm;
736 	struct task_struct *task;
737 	struct etnaviv_gem_object *etnaviv_obj;
738 };
739 
740 static struct page **etnaviv_gem_userptr_do_get_pages(
741 	struct etnaviv_gem_object *etnaviv_obj, struct mm_struct *mm, struct task_struct *task)
742 {
743 	int ret = 0, pinned, npages = etnaviv_obj->base.size >> PAGE_SHIFT;
744 	struct page **pvec;
745 	uintptr_t ptr;
746 
747 	pvec = drm_malloc_ab(npages, sizeof(struct page *));
748 	if (!pvec)
749 		return ERR_PTR(-ENOMEM);
750 
751 	pinned = 0;
752 	ptr = etnaviv_obj->userptr.ptr;
753 
754 	down_read(&mm->mmap_sem);
755 	while (pinned < npages) {
756 		ret = get_user_pages(task, mm, ptr, npages - pinned,
757 				     !etnaviv_obj->userptr.ro, 0,
758 				     pvec + pinned, NULL);
759 		if (ret < 0)
760 			break;
761 
762 		ptr += ret * PAGE_SIZE;
763 		pinned += ret;
764 	}
765 	up_read(&mm->mmap_sem);
766 
767 	if (ret < 0) {
768 		release_pages(pvec, pinned, 0);
769 		drm_free_large(pvec);
770 		return ERR_PTR(ret);
771 	}
772 
773 	return pvec;
774 }
775 
776 static void __etnaviv_gem_userptr_get_pages(struct work_struct *_work)
777 {
778 	struct get_pages_work *work = container_of(_work, typeof(*work), work);
779 	struct etnaviv_gem_object *etnaviv_obj = work->etnaviv_obj;
780 	struct page **pvec;
781 
782 	pvec = etnaviv_gem_userptr_do_get_pages(etnaviv_obj, work->mm, work->task);
783 
784 	mutex_lock(&etnaviv_obj->lock);
785 	if (IS_ERR(pvec)) {
786 		etnaviv_obj->userptr.work = ERR_CAST(pvec);
787 	} else {
788 		etnaviv_obj->userptr.work = NULL;
789 		etnaviv_obj->pages = pvec;
790 	}
791 
792 	mutex_unlock(&etnaviv_obj->lock);
793 	drm_gem_object_unreference_unlocked(&etnaviv_obj->base);
794 
795 	mmput(work->mm);
796 	put_task_struct(work->task);
797 	kfree(work);
798 }
799 
800 static int etnaviv_gem_userptr_get_pages(struct etnaviv_gem_object *etnaviv_obj)
801 {
802 	struct page **pvec = NULL;
803 	struct get_pages_work *work;
804 	struct mm_struct *mm;
805 	int ret, pinned, npages = etnaviv_obj->base.size >> PAGE_SHIFT;
806 
807 	if (etnaviv_obj->userptr.work) {
808 		if (IS_ERR(etnaviv_obj->userptr.work)) {
809 			ret = PTR_ERR(etnaviv_obj->userptr.work);
810 			etnaviv_obj->userptr.work = NULL;
811 		} else {
812 			ret = -EAGAIN;
813 		}
814 		return ret;
815 	}
816 
817 	mm = get_task_mm(etnaviv_obj->userptr.task);
818 	pinned = 0;
819 	if (mm == current->mm) {
820 		pvec = drm_malloc_ab(npages, sizeof(struct page *));
821 		if (!pvec) {
822 			mmput(mm);
823 			return -ENOMEM;
824 		}
825 
826 		pinned = __get_user_pages_fast(etnaviv_obj->userptr.ptr, npages,
827 					       !etnaviv_obj->userptr.ro, pvec);
828 		if (pinned < 0) {
829 			drm_free_large(pvec);
830 			mmput(mm);
831 			return pinned;
832 		}
833 
834 		if (pinned == npages) {
835 			etnaviv_obj->pages = pvec;
836 			mmput(mm);
837 			return 0;
838 		}
839 	}
840 
841 	release_pages(pvec, pinned, 0);
842 	drm_free_large(pvec);
843 
844 	work = kmalloc(sizeof(*work), GFP_KERNEL);
845 	if (!work) {
846 		mmput(mm);
847 		return -ENOMEM;
848 	}
849 
850 	get_task_struct(current);
851 	drm_gem_object_reference(&etnaviv_obj->base);
852 
853 	work->mm = mm;
854 	work->task = current;
855 	work->etnaviv_obj = etnaviv_obj;
856 
857 	etnaviv_obj->userptr.work = &work->work;
858 	INIT_WORK(&work->work, __etnaviv_gem_userptr_get_pages);
859 
860 	etnaviv_queue_work(etnaviv_obj->base.dev, &work->work);
861 
862 	return -EAGAIN;
863 }
864 
865 static void etnaviv_gem_userptr_release(struct etnaviv_gem_object *etnaviv_obj)
866 {
867 	if (etnaviv_obj->sgt) {
868 		etnaviv_gem_scatterlist_unmap(etnaviv_obj);
869 		sg_free_table(etnaviv_obj->sgt);
870 		kfree(etnaviv_obj->sgt);
871 	}
872 	if (etnaviv_obj->pages) {
873 		int npages = etnaviv_obj->base.size >> PAGE_SHIFT;
874 
875 		release_pages(etnaviv_obj->pages, npages, 0);
876 		drm_free_large(etnaviv_obj->pages);
877 	}
878 	put_task_struct(etnaviv_obj->userptr.task);
879 }
880 
881 static const struct etnaviv_gem_ops etnaviv_gem_userptr_ops = {
882 	.get_pages = etnaviv_gem_userptr_get_pages,
883 	.release = etnaviv_gem_userptr_release,
884 	.vmap = etnaviv_gem_vmap_impl,
885 };
886 
887 int etnaviv_gem_new_userptr(struct drm_device *dev, struct drm_file *file,
888 	uintptr_t ptr, u32 size, u32 flags, u32 *handle)
889 {
890 	struct etnaviv_gem_object *etnaviv_obj;
891 	int ret;
892 
893 	ret = etnaviv_gem_new_private(dev, size, ETNA_BO_CACHED, NULL,
894 				      &etnaviv_gem_userptr_ops, &etnaviv_obj);
895 	if (ret)
896 		return ret;
897 
898 	etnaviv_obj->userptr.ptr = ptr;
899 	etnaviv_obj->userptr.task = current;
900 	etnaviv_obj->userptr.ro = !(flags & ETNA_USERPTR_WRITE);
901 	get_task_struct(current);
902 
903 	ret = etnaviv_gem_obj_add(dev, &etnaviv_obj->base);
904 	if (ret) {
905 		drm_gem_object_unreference_unlocked(&etnaviv_obj->base);
906 		return ret;
907 	}
908 
909 	ret = drm_gem_handle_create(file, &etnaviv_obj->base, handle);
910 
911 	/* drop reference from allocate - handle holds it now */
912 	drm_gem_object_unreference_unlocked(&etnaviv_obj->base);
913 
914 	return ret;
915 }
916