1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2015-2018 Etnaviv Project
4  */
5 
6 #include <drm/drm_prime.h>
7 #include <linux/dma-mapping.h>
8 #include <linux/shmem_fs.h>
9 #include <linux/spinlock.h>
10 #include <linux/vmalloc.h>
11 
12 #include "etnaviv_drv.h"
13 #include "etnaviv_gem.h"
14 #include "etnaviv_gpu.h"
15 #include "etnaviv_mmu.h"
16 
17 static struct lock_class_key etnaviv_shm_lock_class;
18 static struct lock_class_key etnaviv_userptr_lock_class;
19 
20 static void etnaviv_gem_scatter_map(struct etnaviv_gem_object *etnaviv_obj)
21 {
22 	struct drm_device *dev = etnaviv_obj->base.dev;
23 	struct sg_table *sgt = etnaviv_obj->sgt;
24 
25 	/*
26 	 * For non-cached buffers, ensure the new pages are clean
27 	 * because display controller, GPU, etc. are not coherent.
28 	 */
29 	if (etnaviv_obj->flags & ETNA_BO_CACHE_MASK)
30 		dma_map_sgtable(dev->dev, sgt, DMA_BIDIRECTIONAL, 0);
31 }
32 
33 static void etnaviv_gem_scatterlist_unmap(struct etnaviv_gem_object *etnaviv_obj)
34 {
35 	struct drm_device *dev = etnaviv_obj->base.dev;
36 	struct sg_table *sgt = etnaviv_obj->sgt;
37 
38 	/*
39 	 * For non-cached buffers, ensure the new pages are clean
40 	 * because display controller, GPU, etc. are not coherent:
41 	 *
42 	 * WARNING: The DMA API does not support concurrent CPU
43 	 * and device access to the memory area.  With BIDIRECTIONAL,
44 	 * we will clean the cache lines which overlap the region,
45 	 * and invalidate all cache lines (partially) contained in
46 	 * the region.
47 	 *
48 	 * If you have dirty data in the overlapping cache lines,
49 	 * that will corrupt the GPU-written data.  If you have
50 	 * written into the remainder of the region, this can
51 	 * discard those writes.
52 	 */
53 	if (etnaviv_obj->flags & ETNA_BO_CACHE_MASK)
54 		dma_unmap_sgtable(dev->dev, sgt, DMA_BIDIRECTIONAL, 0);
55 }
56 
57 /* called with etnaviv_obj->lock held */
58 static int etnaviv_gem_shmem_get_pages(struct etnaviv_gem_object *etnaviv_obj)
59 {
60 	struct drm_device *dev = etnaviv_obj->base.dev;
61 	struct page **p = drm_gem_get_pages(&etnaviv_obj->base);
62 
63 	if (IS_ERR(p)) {
64 		dev_dbg(dev->dev, "could not get pages: %ld\n", PTR_ERR(p));
65 		return PTR_ERR(p);
66 	}
67 
68 	etnaviv_obj->pages = p;
69 
70 	return 0;
71 }
72 
73 static void put_pages(struct etnaviv_gem_object *etnaviv_obj)
74 {
75 	if (etnaviv_obj->sgt) {
76 		etnaviv_gem_scatterlist_unmap(etnaviv_obj);
77 		sg_free_table(etnaviv_obj->sgt);
78 		kfree(etnaviv_obj->sgt);
79 		etnaviv_obj->sgt = NULL;
80 	}
81 	if (etnaviv_obj->pages) {
82 		drm_gem_put_pages(&etnaviv_obj->base, etnaviv_obj->pages,
83 				  true, false);
84 
85 		etnaviv_obj->pages = NULL;
86 	}
87 }
88 
89 struct page **etnaviv_gem_get_pages(struct etnaviv_gem_object *etnaviv_obj)
90 {
91 	int ret;
92 
93 	lockdep_assert_held(&etnaviv_obj->lock);
94 
95 	if (!etnaviv_obj->pages) {
96 		ret = etnaviv_obj->ops->get_pages(etnaviv_obj);
97 		if (ret < 0)
98 			return ERR_PTR(ret);
99 	}
100 
101 	if (!etnaviv_obj->sgt) {
102 		struct drm_device *dev = etnaviv_obj->base.dev;
103 		int npages = etnaviv_obj->base.size >> PAGE_SHIFT;
104 		struct sg_table *sgt;
105 
106 		sgt = drm_prime_pages_to_sg(etnaviv_obj->base.dev,
107 					    etnaviv_obj->pages, npages);
108 		if (IS_ERR(sgt)) {
109 			dev_err(dev->dev, "failed to allocate sgt: %ld\n",
110 				PTR_ERR(sgt));
111 			return ERR_CAST(sgt);
112 		}
113 
114 		etnaviv_obj->sgt = sgt;
115 
116 		etnaviv_gem_scatter_map(etnaviv_obj);
117 	}
118 
119 	return etnaviv_obj->pages;
120 }
121 
122 void etnaviv_gem_put_pages(struct etnaviv_gem_object *etnaviv_obj)
123 {
124 	lockdep_assert_held(&etnaviv_obj->lock);
125 	/* when we start tracking the pin count, then do something here */
126 }
127 
128 static int etnaviv_gem_mmap_obj(struct etnaviv_gem_object *etnaviv_obj,
129 		struct vm_area_struct *vma)
130 {
131 	pgprot_t vm_page_prot;
132 
133 	vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTDUMP;
134 
135 	vm_page_prot = vm_get_page_prot(vma->vm_flags);
136 
137 	if (etnaviv_obj->flags & ETNA_BO_WC) {
138 		vma->vm_page_prot = pgprot_writecombine(vm_page_prot);
139 	} else if (etnaviv_obj->flags & ETNA_BO_UNCACHED) {
140 		vma->vm_page_prot = pgprot_noncached(vm_page_prot);
141 	} else {
142 		/*
143 		 * Shunt off cached objs to shmem file so they have their own
144 		 * address_space (so unmap_mapping_range does what we want,
145 		 * in particular in the case of mmap'd dmabufs)
146 		 */
147 		vma->vm_pgoff = 0;
148 		vma_set_file(vma, etnaviv_obj->base.filp);
149 
150 		vma->vm_page_prot = vm_page_prot;
151 	}
152 
153 	return 0;
154 }
155 
156 static int etnaviv_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
157 {
158 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
159 
160 	return etnaviv_obj->ops->mmap(etnaviv_obj, vma);
161 }
162 
163 static vm_fault_t etnaviv_gem_fault(struct vm_fault *vmf)
164 {
165 	struct vm_area_struct *vma = vmf->vma;
166 	struct drm_gem_object *obj = vma->vm_private_data;
167 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
168 	struct page **pages, *page;
169 	pgoff_t pgoff;
170 	int err;
171 
172 	/*
173 	 * Make sure we don't parallel update on a fault, nor move or remove
174 	 * something from beneath our feet.  Note that vmf_insert_page() is
175 	 * specifically coded to take care of this, so we don't have to.
176 	 */
177 	err = mutex_lock_interruptible(&etnaviv_obj->lock);
178 	if (err)
179 		return VM_FAULT_NOPAGE;
180 	/* make sure we have pages attached now */
181 	pages = etnaviv_gem_get_pages(etnaviv_obj);
182 	mutex_unlock(&etnaviv_obj->lock);
183 
184 	if (IS_ERR(pages)) {
185 		err = PTR_ERR(pages);
186 		return vmf_error(err);
187 	}
188 
189 	/* We don't use vmf->pgoff since that has the fake offset: */
190 	pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
191 
192 	page = pages[pgoff];
193 
194 	VERB("Inserting %p pfn %lx, pa %lx", (void *)vmf->address,
195 	     page_to_pfn(page), page_to_pfn(page) << PAGE_SHIFT);
196 
197 	return vmf_insert_page(vma, vmf->address, page);
198 }
199 
200 int etnaviv_gem_mmap_offset(struct drm_gem_object *obj, u64 *offset)
201 {
202 	int ret;
203 
204 	/* Make it mmapable */
205 	ret = drm_gem_create_mmap_offset(obj);
206 	if (ret)
207 		dev_err(obj->dev->dev, "could not allocate mmap offset\n");
208 	else
209 		*offset = drm_vma_node_offset_addr(&obj->vma_node);
210 
211 	return ret;
212 }
213 
214 static struct etnaviv_vram_mapping *
215 etnaviv_gem_get_vram_mapping(struct etnaviv_gem_object *obj,
216 			     struct etnaviv_iommu_context *context)
217 {
218 	struct etnaviv_vram_mapping *mapping;
219 
220 	list_for_each_entry(mapping, &obj->vram_list, obj_node) {
221 		if (mapping->context == context)
222 			return mapping;
223 	}
224 
225 	return NULL;
226 }
227 
228 void etnaviv_gem_mapping_unreference(struct etnaviv_vram_mapping *mapping)
229 {
230 	struct etnaviv_gem_object *etnaviv_obj = mapping->object;
231 
232 	mutex_lock(&etnaviv_obj->lock);
233 	WARN_ON(mapping->use == 0);
234 	mapping->use -= 1;
235 	mutex_unlock(&etnaviv_obj->lock);
236 
237 	drm_gem_object_put(&etnaviv_obj->base);
238 }
239 
240 struct etnaviv_vram_mapping *etnaviv_gem_mapping_get(
241 	struct drm_gem_object *obj, struct etnaviv_iommu_context *mmu_context,
242 	u64 va)
243 {
244 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
245 	struct etnaviv_vram_mapping *mapping;
246 	struct page **pages;
247 	int ret = 0;
248 
249 	mutex_lock(&etnaviv_obj->lock);
250 	mapping = etnaviv_gem_get_vram_mapping(etnaviv_obj, mmu_context);
251 	if (mapping) {
252 		/*
253 		 * Holding the object lock prevents the use count changing
254 		 * beneath us.  If the use count is zero, the MMU might be
255 		 * reaping this object, so take the lock and re-check that
256 		 * the MMU owns this mapping to close this race.
257 		 */
258 		if (mapping->use == 0) {
259 			mutex_lock(&mmu_context->lock);
260 			if (mapping->context == mmu_context)
261 				mapping->use += 1;
262 			else
263 				mapping = NULL;
264 			mutex_unlock(&mmu_context->lock);
265 			if (mapping)
266 				goto out;
267 		} else {
268 			mapping->use += 1;
269 			goto out;
270 		}
271 	}
272 
273 	pages = etnaviv_gem_get_pages(etnaviv_obj);
274 	if (IS_ERR(pages)) {
275 		ret = PTR_ERR(pages);
276 		goto out;
277 	}
278 
279 	/*
280 	 * See if we have a reaped vram mapping we can re-use before
281 	 * allocating a fresh mapping.
282 	 */
283 	mapping = etnaviv_gem_get_vram_mapping(etnaviv_obj, NULL);
284 	if (!mapping) {
285 		mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
286 		if (!mapping) {
287 			ret = -ENOMEM;
288 			goto out;
289 		}
290 
291 		INIT_LIST_HEAD(&mapping->scan_node);
292 		mapping->object = etnaviv_obj;
293 	} else {
294 		list_del(&mapping->obj_node);
295 	}
296 
297 	mapping->use = 1;
298 
299 	ret = etnaviv_iommu_map_gem(mmu_context, etnaviv_obj,
300 				    mmu_context->global->memory_base,
301 				    mapping, va);
302 	if (ret < 0)
303 		kfree(mapping);
304 	else
305 		list_add_tail(&mapping->obj_node, &etnaviv_obj->vram_list);
306 
307 out:
308 	mutex_unlock(&etnaviv_obj->lock);
309 
310 	if (ret)
311 		return ERR_PTR(ret);
312 
313 	/* Take a reference on the object */
314 	drm_gem_object_get(obj);
315 	return mapping;
316 }
317 
318 void *etnaviv_gem_vmap(struct drm_gem_object *obj)
319 {
320 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
321 
322 	if (etnaviv_obj->vaddr)
323 		return etnaviv_obj->vaddr;
324 
325 	mutex_lock(&etnaviv_obj->lock);
326 	/*
327 	 * Need to check again, as we might have raced with another thread
328 	 * while waiting for the mutex.
329 	 */
330 	if (!etnaviv_obj->vaddr)
331 		etnaviv_obj->vaddr = etnaviv_obj->ops->vmap(etnaviv_obj);
332 	mutex_unlock(&etnaviv_obj->lock);
333 
334 	return etnaviv_obj->vaddr;
335 }
336 
337 static void *etnaviv_gem_vmap_impl(struct etnaviv_gem_object *obj)
338 {
339 	struct page **pages;
340 
341 	lockdep_assert_held(&obj->lock);
342 
343 	pages = etnaviv_gem_get_pages(obj);
344 	if (IS_ERR(pages))
345 		return NULL;
346 
347 	return vmap(pages, obj->base.size >> PAGE_SHIFT,
348 			VM_MAP, pgprot_writecombine(PAGE_KERNEL));
349 }
350 
351 static inline enum dma_data_direction etnaviv_op_to_dma_dir(u32 op)
352 {
353 	if (op & ETNA_PREP_READ)
354 		return DMA_FROM_DEVICE;
355 	else if (op & ETNA_PREP_WRITE)
356 		return DMA_TO_DEVICE;
357 	else
358 		return DMA_BIDIRECTIONAL;
359 }
360 
361 int etnaviv_gem_cpu_prep(struct drm_gem_object *obj, u32 op,
362 		struct drm_etnaviv_timespec *timeout)
363 {
364 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
365 	struct drm_device *dev = obj->dev;
366 	bool write = !!(op & ETNA_PREP_WRITE);
367 	int ret;
368 
369 	if (!etnaviv_obj->sgt) {
370 		void *ret;
371 
372 		mutex_lock(&etnaviv_obj->lock);
373 		ret = etnaviv_gem_get_pages(etnaviv_obj);
374 		mutex_unlock(&etnaviv_obj->lock);
375 		if (IS_ERR(ret))
376 			return PTR_ERR(ret);
377 	}
378 
379 	if (op & ETNA_PREP_NOSYNC) {
380 		if (!dma_resv_test_signaled(obj->resv,
381 					    dma_resv_usage_rw(write)))
382 			return -EBUSY;
383 	} else {
384 		unsigned long remain = etnaviv_timeout_to_jiffies(timeout);
385 
386 		ret = dma_resv_wait_timeout(obj->resv, dma_resv_usage_rw(write),
387 					    true, remain);
388 		if (ret <= 0)
389 			return ret == 0 ? -ETIMEDOUT : ret;
390 	}
391 
392 	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
393 		dma_sync_sgtable_for_cpu(dev->dev, etnaviv_obj->sgt,
394 					 etnaviv_op_to_dma_dir(op));
395 		etnaviv_obj->last_cpu_prep_op = op;
396 	}
397 
398 	return 0;
399 }
400 
401 int etnaviv_gem_cpu_fini(struct drm_gem_object *obj)
402 {
403 	struct drm_device *dev = obj->dev;
404 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
405 
406 	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
407 		/* fini without a prep is almost certainly a userspace error */
408 		WARN_ON(etnaviv_obj->last_cpu_prep_op == 0);
409 		dma_sync_sgtable_for_device(dev->dev, etnaviv_obj->sgt,
410 			etnaviv_op_to_dma_dir(etnaviv_obj->last_cpu_prep_op));
411 		etnaviv_obj->last_cpu_prep_op = 0;
412 	}
413 
414 	return 0;
415 }
416 
417 int etnaviv_gem_wait_bo(struct etnaviv_gpu *gpu, struct drm_gem_object *obj,
418 	struct drm_etnaviv_timespec *timeout)
419 {
420 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
421 
422 	return etnaviv_gpu_wait_obj_inactive(gpu, etnaviv_obj, timeout);
423 }
424 
425 #ifdef CONFIG_DEBUG_FS
426 static void etnaviv_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
427 {
428 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
429 	struct dma_resv *robj = obj->resv;
430 	unsigned long off = drm_vma_node_start(&obj->vma_node);
431 	int r;
432 
433 	seq_printf(m, "%08x: %c %2d (%2d) %08lx %p %zd\n",
434 			etnaviv_obj->flags, is_active(etnaviv_obj) ? 'A' : 'I',
435 			obj->name, kref_read(&obj->refcount),
436 			off, etnaviv_obj->vaddr, obj->size);
437 
438 	r = dma_resv_lock(robj, NULL);
439 	if (r)
440 		return;
441 
442 	dma_resv_describe(robj, m);
443 	dma_resv_unlock(robj);
444 }
445 
446 void etnaviv_gem_describe_objects(struct etnaviv_drm_private *priv,
447 	struct seq_file *m)
448 {
449 	struct etnaviv_gem_object *etnaviv_obj;
450 	int count = 0;
451 	size_t size = 0;
452 
453 	mutex_lock(&priv->gem_lock);
454 	list_for_each_entry(etnaviv_obj, &priv->gem_list, gem_node) {
455 		struct drm_gem_object *obj = &etnaviv_obj->base;
456 
457 		seq_puts(m, "   ");
458 		etnaviv_gem_describe(obj, m);
459 		count++;
460 		size += obj->size;
461 	}
462 	mutex_unlock(&priv->gem_lock);
463 
464 	seq_printf(m, "Total %d objects, %zu bytes\n", count, size);
465 }
466 #endif
467 
468 static void etnaviv_gem_shmem_release(struct etnaviv_gem_object *etnaviv_obj)
469 {
470 	vunmap(etnaviv_obj->vaddr);
471 	put_pages(etnaviv_obj);
472 }
473 
474 static const struct etnaviv_gem_ops etnaviv_gem_shmem_ops = {
475 	.get_pages = etnaviv_gem_shmem_get_pages,
476 	.release = etnaviv_gem_shmem_release,
477 	.vmap = etnaviv_gem_vmap_impl,
478 	.mmap = etnaviv_gem_mmap_obj,
479 };
480 
481 void etnaviv_gem_free_object(struct drm_gem_object *obj)
482 {
483 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
484 	struct etnaviv_drm_private *priv = obj->dev->dev_private;
485 	struct etnaviv_vram_mapping *mapping, *tmp;
486 
487 	/* object should not be active */
488 	WARN_ON(is_active(etnaviv_obj));
489 
490 	mutex_lock(&priv->gem_lock);
491 	list_del(&etnaviv_obj->gem_node);
492 	mutex_unlock(&priv->gem_lock);
493 
494 	list_for_each_entry_safe(mapping, tmp, &etnaviv_obj->vram_list,
495 				 obj_node) {
496 		struct etnaviv_iommu_context *context = mapping->context;
497 
498 		WARN_ON(mapping->use);
499 
500 		if (context)
501 			etnaviv_iommu_unmap_gem(context, mapping);
502 
503 		list_del(&mapping->obj_node);
504 		kfree(mapping);
505 	}
506 
507 	drm_gem_free_mmap_offset(obj);
508 	etnaviv_obj->ops->release(etnaviv_obj);
509 	drm_gem_object_release(obj);
510 
511 	kfree(etnaviv_obj);
512 }
513 
514 void etnaviv_gem_obj_add(struct drm_device *dev, struct drm_gem_object *obj)
515 {
516 	struct etnaviv_drm_private *priv = dev->dev_private;
517 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
518 
519 	mutex_lock(&priv->gem_lock);
520 	list_add_tail(&etnaviv_obj->gem_node, &priv->gem_list);
521 	mutex_unlock(&priv->gem_lock);
522 }
523 
524 static const struct vm_operations_struct vm_ops = {
525 	.fault = etnaviv_gem_fault,
526 	.open = drm_gem_vm_open,
527 	.close = drm_gem_vm_close,
528 };
529 
530 static const struct drm_gem_object_funcs etnaviv_gem_object_funcs = {
531 	.free = etnaviv_gem_free_object,
532 	.pin = etnaviv_gem_prime_pin,
533 	.unpin = etnaviv_gem_prime_unpin,
534 	.get_sg_table = etnaviv_gem_prime_get_sg_table,
535 	.vmap = etnaviv_gem_prime_vmap,
536 	.mmap = etnaviv_gem_mmap,
537 	.vm_ops = &vm_ops,
538 };
539 
540 static int etnaviv_gem_new_impl(struct drm_device *dev, u32 size, u32 flags,
541 	const struct etnaviv_gem_ops *ops, struct drm_gem_object **obj)
542 {
543 	struct etnaviv_gem_object *etnaviv_obj;
544 	unsigned sz = sizeof(*etnaviv_obj);
545 	bool valid = true;
546 
547 	/* validate flags */
548 	switch (flags & ETNA_BO_CACHE_MASK) {
549 	case ETNA_BO_UNCACHED:
550 	case ETNA_BO_CACHED:
551 	case ETNA_BO_WC:
552 		break;
553 	default:
554 		valid = false;
555 	}
556 
557 	if (!valid) {
558 		dev_err(dev->dev, "invalid cache flag: %x\n",
559 			(flags & ETNA_BO_CACHE_MASK));
560 		return -EINVAL;
561 	}
562 
563 	etnaviv_obj = kzalloc(sz, GFP_KERNEL);
564 	if (!etnaviv_obj)
565 		return -ENOMEM;
566 
567 	etnaviv_obj->flags = flags;
568 	etnaviv_obj->ops = ops;
569 
570 	mutex_init(&etnaviv_obj->lock);
571 	INIT_LIST_HEAD(&etnaviv_obj->vram_list);
572 
573 	*obj = &etnaviv_obj->base;
574 	(*obj)->funcs = &etnaviv_gem_object_funcs;
575 
576 	return 0;
577 }
578 
579 /* convenience method to construct a GEM buffer object, and userspace handle */
580 int etnaviv_gem_new_handle(struct drm_device *dev, struct drm_file *file,
581 	u32 size, u32 flags, u32 *handle)
582 {
583 	struct etnaviv_drm_private *priv = dev->dev_private;
584 	struct drm_gem_object *obj = NULL;
585 	int ret;
586 
587 	size = PAGE_ALIGN(size);
588 
589 	ret = etnaviv_gem_new_impl(dev, size, flags,
590 				   &etnaviv_gem_shmem_ops, &obj);
591 	if (ret)
592 		goto fail;
593 
594 	lockdep_set_class(&to_etnaviv_bo(obj)->lock, &etnaviv_shm_lock_class);
595 
596 	ret = drm_gem_object_init(dev, obj, size);
597 	if (ret)
598 		goto fail;
599 
600 	/*
601 	 * Our buffers are kept pinned, so allocating them from the MOVABLE
602 	 * zone is a really bad idea, and conflicts with CMA. See comments
603 	 * above new_inode() why this is required _and_ expected if you're
604 	 * going to pin these pages.
605 	 */
606 	mapping_set_gfp_mask(obj->filp->f_mapping, priv->shm_gfp_mask);
607 
608 	etnaviv_gem_obj_add(dev, obj);
609 
610 	ret = drm_gem_handle_create(file, obj, handle);
611 
612 	/* drop reference from allocate - handle holds it now */
613 fail:
614 	drm_gem_object_put(obj);
615 
616 	return ret;
617 }
618 
619 int etnaviv_gem_new_private(struct drm_device *dev, size_t size, u32 flags,
620 	const struct etnaviv_gem_ops *ops, struct etnaviv_gem_object **res)
621 {
622 	struct drm_gem_object *obj;
623 	int ret;
624 
625 	ret = etnaviv_gem_new_impl(dev, size, flags, ops, &obj);
626 	if (ret)
627 		return ret;
628 
629 	drm_gem_private_object_init(dev, obj, size);
630 
631 	*res = to_etnaviv_bo(obj);
632 
633 	return 0;
634 }
635 
636 static int etnaviv_gem_userptr_get_pages(struct etnaviv_gem_object *etnaviv_obj)
637 {
638 	struct page **pvec = NULL;
639 	struct etnaviv_gem_userptr *userptr = &etnaviv_obj->userptr;
640 	int ret, pinned = 0, npages = etnaviv_obj->base.size >> PAGE_SHIFT;
641 
642 	might_lock_read(&current->mm->mmap_lock);
643 
644 	if (userptr->mm != current->mm)
645 		return -EPERM;
646 
647 	pvec = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
648 	if (!pvec)
649 		return -ENOMEM;
650 
651 	do {
652 		unsigned num_pages = npages - pinned;
653 		uint64_t ptr = userptr->ptr + pinned * PAGE_SIZE;
654 		struct page **pages = pvec + pinned;
655 
656 		ret = pin_user_pages_fast(ptr, num_pages,
657 					  FOLL_WRITE | FOLL_FORCE | FOLL_LONGTERM,
658 					  pages);
659 		if (ret < 0) {
660 			unpin_user_pages(pvec, pinned);
661 			kvfree(pvec);
662 			return ret;
663 		}
664 
665 		pinned += ret;
666 
667 	} while (pinned < npages);
668 
669 	etnaviv_obj->pages = pvec;
670 
671 	return 0;
672 }
673 
674 static void etnaviv_gem_userptr_release(struct etnaviv_gem_object *etnaviv_obj)
675 {
676 	if (etnaviv_obj->sgt) {
677 		etnaviv_gem_scatterlist_unmap(etnaviv_obj);
678 		sg_free_table(etnaviv_obj->sgt);
679 		kfree(etnaviv_obj->sgt);
680 	}
681 	if (etnaviv_obj->pages) {
682 		int npages = etnaviv_obj->base.size >> PAGE_SHIFT;
683 
684 		unpin_user_pages(etnaviv_obj->pages, npages);
685 		kvfree(etnaviv_obj->pages);
686 	}
687 }
688 
689 static int etnaviv_gem_userptr_mmap_obj(struct etnaviv_gem_object *etnaviv_obj,
690 		struct vm_area_struct *vma)
691 {
692 	return -EINVAL;
693 }
694 
695 static const struct etnaviv_gem_ops etnaviv_gem_userptr_ops = {
696 	.get_pages = etnaviv_gem_userptr_get_pages,
697 	.release = etnaviv_gem_userptr_release,
698 	.vmap = etnaviv_gem_vmap_impl,
699 	.mmap = etnaviv_gem_userptr_mmap_obj,
700 };
701 
702 int etnaviv_gem_new_userptr(struct drm_device *dev, struct drm_file *file,
703 	uintptr_t ptr, u32 size, u32 flags, u32 *handle)
704 {
705 	struct etnaviv_gem_object *etnaviv_obj;
706 	int ret;
707 
708 	ret = etnaviv_gem_new_private(dev, size, ETNA_BO_CACHED,
709 				      &etnaviv_gem_userptr_ops, &etnaviv_obj);
710 	if (ret)
711 		return ret;
712 
713 	lockdep_set_class(&etnaviv_obj->lock, &etnaviv_userptr_lock_class);
714 
715 	etnaviv_obj->userptr.ptr = ptr;
716 	etnaviv_obj->userptr.mm = current->mm;
717 	etnaviv_obj->userptr.ro = !(flags & ETNA_USERPTR_WRITE);
718 
719 	etnaviv_gem_obj_add(dev, &etnaviv_obj->base);
720 
721 	ret = drm_gem_handle_create(file, &etnaviv_obj->base, handle);
722 
723 	/* drop reference from allocate - handle holds it now */
724 	drm_gem_object_put(&etnaviv_obj->base);
725 	return ret;
726 }
727