[go: nahoru, domu]

1/*
2 * Copyright (C) 2012 Russell King
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8#include <linux/dma-buf.h>
9#include <linux/dma-mapping.h>
10#include <linux/shmem_fs.h>
11#include <drm/drmP.h>
12#include "armada_drm.h"
13#include "armada_gem.h"
14#include <drm/armada_drm.h>
15#include "armada_ioctlP.h"
16
17static int armada_gem_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
18{
19	struct armada_gem_object *obj = drm_to_armada_gem(vma->vm_private_data);
20	unsigned long addr = (unsigned long)vmf->virtual_address;
21	unsigned long pfn = obj->phys_addr >> PAGE_SHIFT;
22	int ret;
23
24	pfn += (addr - vma->vm_start) >> PAGE_SHIFT;
25	ret = vm_insert_pfn(vma, addr, pfn);
26
27	switch (ret) {
28	case 0:
29	case -EBUSY:
30		return VM_FAULT_NOPAGE;
31	case -ENOMEM:
32		return VM_FAULT_OOM;
33	default:
34		return VM_FAULT_SIGBUS;
35	}
36}
37
38const struct vm_operations_struct armada_gem_vm_ops = {
39	.fault	= armada_gem_vm_fault,
40	.open	= drm_gem_vm_open,
41	.close	= drm_gem_vm_close,
42};
43
44static size_t roundup_gem_size(size_t size)
45{
46	return roundup(size, PAGE_SIZE);
47}
48
49/* dev->struct_mutex is held here */
50void armada_gem_free_object(struct drm_gem_object *obj)
51{
52	struct armada_gem_object *dobj = drm_to_armada_gem(obj);
53
54	DRM_DEBUG_DRIVER("release obj %p\n", dobj);
55
56	drm_gem_free_mmap_offset(&dobj->obj);
57
58	if (dobj->page) {
59		/* page backed memory */
60		unsigned int order = get_order(dobj->obj.size);
61		__free_pages(dobj->page, order);
62	} else if (dobj->linear) {
63		/* linear backed memory */
64		drm_mm_remove_node(dobj->linear);
65		kfree(dobj->linear);
66		if (dobj->addr)
67			iounmap(dobj->addr);
68	}
69
70	if (dobj->obj.import_attach) {
71		/* We only ever display imported data */
72		dma_buf_unmap_attachment(dobj->obj.import_attach, dobj->sgt,
73					 DMA_TO_DEVICE);
74		drm_prime_gem_destroy(&dobj->obj, NULL);
75	}
76
77	drm_gem_object_release(&dobj->obj);
78
79	kfree(dobj);
80}
81
82int
83armada_gem_linear_back(struct drm_device *dev, struct armada_gem_object *obj)
84{
85	struct armada_private *priv = dev->dev_private;
86	size_t size = obj->obj.size;
87
88	if (obj->page || obj->linear)
89		return 0;
90
91	/*
92	 * If it is a small allocation (typically cursor, which will
93	 * be 32x64 or 64x32 ARGB pixels) try to get it from the system.
94	 * Framebuffers will never be this small (our minimum size for
95	 * framebuffers is larger than this anyway.)  Such objects are
96	 * only accessed by the CPU so we don't need any special handing
97	 * here.
98	 */
99	if (size <= 8192) {
100		unsigned int order = get_order(size);
101		struct page *p = alloc_pages(GFP_KERNEL, order);
102
103		if (p) {
104			obj->addr = page_address(p);
105			obj->phys_addr = page_to_phys(p);
106			obj->page = p;
107
108			memset(obj->addr, 0, PAGE_ALIGN(size));
109		}
110	}
111
112	/*
113	 * We could grab something from CMA if it's enabled, but that
114	 * involves building in a problem:
115	 *
116	 * CMA's interface uses dma_alloc_coherent(), which provides us
117	 * with an CPU virtual address and a device address.
118	 *
119	 * The CPU virtual address may be either an address in the kernel
120	 * direct mapped region (for example, as it would be on x86) or
121	 * it may be remapped into another part of kernel memory space
122	 * (eg, as it would be on ARM.)  This means virt_to_phys() on the
123	 * returned virtual address is invalid depending on the architecture
124	 * implementation.
125	 *
126	 * The device address may also not be a physical address; it may
127	 * be that there is some kind of remapping between the device and
128	 * system RAM, which makes the use of the device address also
129	 * unsafe to re-use as a physical address.
130	 *
131	 * This makes DRM usage of dma_alloc_coherent() in a generic way
132	 * at best very questionable and unsafe.
133	 */
134
135	/* Otherwise, grab it from our linear allocation */
136	if (!obj->page) {
137		struct drm_mm_node *node;
138		unsigned align = min_t(unsigned, size, SZ_2M);
139		void __iomem *ptr;
140		int ret;
141
142		node = kzalloc(sizeof(*node), GFP_KERNEL);
143		if (!node)
144			return -ENOSPC;
145
146		mutex_lock(&dev->struct_mutex);
147		ret = drm_mm_insert_node(&priv->linear, node, size, align,
148					 DRM_MM_SEARCH_DEFAULT);
149		mutex_unlock(&dev->struct_mutex);
150		if (ret) {
151			kfree(node);
152			return ret;
153		}
154
155		obj->linear = node;
156
157		/* Ensure that the memory we're returning is cleared. */
158		ptr = ioremap_wc(obj->linear->start, size);
159		if (!ptr) {
160			mutex_lock(&dev->struct_mutex);
161			drm_mm_remove_node(obj->linear);
162			mutex_unlock(&dev->struct_mutex);
163			kfree(obj->linear);
164			obj->linear = NULL;
165			return -ENOMEM;
166		}
167
168		memset_io(ptr, 0, size);
169		iounmap(ptr);
170
171		obj->phys_addr = obj->linear->start;
172		obj->dev_addr = obj->linear->start;
173	}
174
175	DRM_DEBUG_DRIVER("obj %p phys %#llx dev %#llx\n", obj,
176			 (unsigned long long)obj->phys_addr,
177			 (unsigned long long)obj->dev_addr);
178
179	return 0;
180}
181
182void *
183armada_gem_map_object(struct drm_device *dev, struct armada_gem_object *dobj)
184{
185	/* only linear objects need to be ioremap'd */
186	if (!dobj->addr && dobj->linear)
187		dobj->addr = ioremap_wc(dobj->phys_addr, dobj->obj.size);
188	return dobj->addr;
189}
190
191struct armada_gem_object *
192armada_gem_alloc_private_object(struct drm_device *dev, size_t size)
193{
194	struct armada_gem_object *obj;
195
196	size = roundup_gem_size(size);
197
198	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
199	if (!obj)
200		return NULL;
201
202	drm_gem_private_object_init(dev, &obj->obj, size);
203	obj->dev_addr = DMA_ERROR_CODE;
204
205	DRM_DEBUG_DRIVER("alloc private obj %p size %zu\n", obj, size);
206
207	return obj;
208}
209
210struct armada_gem_object *armada_gem_alloc_object(struct drm_device *dev,
211	size_t size)
212{
213	struct armada_gem_object *obj;
214	struct address_space *mapping;
215
216	size = roundup_gem_size(size);
217
218	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
219	if (!obj)
220		return NULL;
221
222	if (drm_gem_object_init(dev, &obj->obj, size)) {
223		kfree(obj);
224		return NULL;
225	}
226
227	obj->dev_addr = DMA_ERROR_CODE;
228
229	mapping = obj->obj.filp->f_path.dentry->d_inode->i_mapping;
230	mapping_set_gfp_mask(mapping, GFP_HIGHUSER | __GFP_RECLAIMABLE);
231
232	DRM_DEBUG_DRIVER("alloc obj %p size %zu\n", obj, size);
233
234	return obj;
235}
236
237/* Dumb alloc support */
238int armada_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
239	struct drm_mode_create_dumb *args)
240{
241	struct armada_gem_object *dobj;
242	u32 handle;
243	size_t size;
244	int ret;
245
246	args->pitch = armada_pitch(args->width, args->bpp);
247	args->size = size = args->pitch * args->height;
248
249	dobj = armada_gem_alloc_private_object(dev, size);
250	if (dobj == NULL)
251		return -ENOMEM;
252
253	ret = armada_gem_linear_back(dev, dobj);
254	if (ret)
255		goto err;
256
257	ret = drm_gem_handle_create(file, &dobj->obj, &handle);
258	if (ret)
259		goto err;
260
261	args->handle = handle;
262
263	/* drop reference from allocate - handle holds it now */
264	DRM_DEBUG_DRIVER("obj %p size %zu handle %#x\n", dobj, size, handle);
265 err:
266	drm_gem_object_unreference_unlocked(&dobj->obj);
267	return ret;
268}
269
270int armada_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
271	uint32_t handle, uint64_t *offset)
272{
273	struct armada_gem_object *obj;
274	int ret = 0;
275
276	mutex_lock(&dev->struct_mutex);
277	obj = armada_gem_object_lookup(dev, file, handle);
278	if (!obj) {
279		DRM_ERROR("failed to lookup gem object\n");
280		ret = -EINVAL;
281		goto err_unlock;
282	}
283
284	/* Don't allow imported objects to be mapped */
285	if (obj->obj.import_attach) {
286		ret = -EINVAL;
287		goto err_unlock;
288	}
289
290	ret = drm_gem_create_mmap_offset(&obj->obj);
291	if (ret == 0) {
292		*offset = drm_vma_node_offset_addr(&obj->obj.vma_node);
293		DRM_DEBUG_DRIVER("handle %#x offset %llx\n", handle, *offset);
294	}
295
296	drm_gem_object_unreference(&obj->obj);
297 err_unlock:
298	mutex_unlock(&dev->struct_mutex);
299
300	return ret;
301}
302
303int armada_gem_dumb_destroy(struct drm_file *file, struct drm_device *dev,
304	uint32_t handle)
305{
306	return drm_gem_handle_delete(file, handle);
307}
308
309/* Private driver gem ioctls */
310int armada_gem_create_ioctl(struct drm_device *dev, void *data,
311	struct drm_file *file)
312{
313	struct drm_armada_gem_create *args = data;
314	struct armada_gem_object *dobj;
315	size_t size;
316	u32 handle;
317	int ret;
318
319	if (args->size == 0)
320		return -ENOMEM;
321
322	size = args->size;
323
324	dobj = armada_gem_alloc_object(dev, size);
325	if (dobj == NULL)
326		return -ENOMEM;
327
328	ret = drm_gem_handle_create(file, &dobj->obj, &handle);
329	if (ret)
330		goto err;
331
332	args->handle = handle;
333
334	/* drop reference from allocate - handle holds it now */
335	DRM_DEBUG_DRIVER("obj %p size %zu handle %#x\n", dobj, size, handle);
336 err:
337	drm_gem_object_unreference_unlocked(&dobj->obj);
338	return ret;
339}
340
341/* Map a shmem-backed object into process memory space */
342int armada_gem_mmap_ioctl(struct drm_device *dev, void *data,
343	struct drm_file *file)
344{
345	struct drm_armada_gem_mmap *args = data;
346	struct armada_gem_object *dobj;
347	unsigned long addr;
348
349	dobj = armada_gem_object_lookup(dev, file, args->handle);
350	if (dobj == NULL)
351		return -ENOENT;
352
353	if (!dobj->obj.filp) {
354		drm_gem_object_unreference(&dobj->obj);
355		return -EINVAL;
356	}
357
358	addr = vm_mmap(dobj->obj.filp, 0, args->size, PROT_READ | PROT_WRITE,
359		       MAP_SHARED, args->offset);
360	drm_gem_object_unreference(&dobj->obj);
361	if (IS_ERR_VALUE(addr))
362		return addr;
363
364	args->addr = addr;
365
366	return 0;
367}
368
369int armada_gem_pwrite_ioctl(struct drm_device *dev, void *data,
370	struct drm_file *file)
371{
372	struct drm_armada_gem_pwrite *args = data;
373	struct armada_gem_object *dobj;
374	char __user *ptr;
375	int ret;
376
377	DRM_DEBUG_DRIVER("handle %u off %u size %u ptr 0x%llx\n",
378		args->handle, args->offset, args->size, args->ptr);
379
380	if (args->size == 0)
381		return 0;
382
383	ptr = (char __user *)(uintptr_t)args->ptr;
384
385	if (!access_ok(VERIFY_READ, ptr, args->size))
386		return -EFAULT;
387
388	ret = fault_in_multipages_readable(ptr, args->size);
389	if (ret)
390		return ret;
391
392	dobj = armada_gem_object_lookup(dev, file, args->handle);
393	if (dobj == NULL)
394		return -ENOENT;
395
396	/* Must be a kernel-mapped object */
397	if (!dobj->addr)
398		return -EINVAL;
399
400	if (args->offset > dobj->obj.size ||
401	    args->size > dobj->obj.size - args->offset) {
402		DRM_ERROR("invalid size: object size %u\n", dobj->obj.size);
403		ret = -EINVAL;
404		goto unref;
405	}
406
407	if (copy_from_user(dobj->addr + args->offset, ptr, args->size)) {
408		ret = -EFAULT;
409	} else if (dobj->update) {
410		dobj->update(dobj->update_data);
411		ret = 0;
412	}
413
414 unref:
415	drm_gem_object_unreference_unlocked(&dobj->obj);
416	return ret;
417}
418
419/* Prime support */
420struct sg_table *
421armada_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,
422	enum dma_data_direction dir)
423{
424	struct drm_gem_object *obj = attach->dmabuf->priv;
425	struct armada_gem_object *dobj = drm_to_armada_gem(obj);
426	struct scatterlist *sg;
427	struct sg_table *sgt;
428	int i, num;
429
430	sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
431	if (!sgt)
432		return NULL;
433
434	if (dobj->obj.filp) {
435		struct address_space *mapping;
436		int count;
437
438		count = dobj->obj.size / PAGE_SIZE;
439		if (sg_alloc_table(sgt, count, GFP_KERNEL))
440			goto free_sgt;
441
442		mapping = file_inode(dobj->obj.filp)->i_mapping;
443
444		for_each_sg(sgt->sgl, sg, count, i) {
445			struct page *page;
446
447			page = shmem_read_mapping_page(mapping, i);
448			if (IS_ERR(page)) {
449				num = i;
450				goto release;
451			}
452
453			sg_set_page(sg, page, PAGE_SIZE, 0);
454		}
455
456		if (dma_map_sg(attach->dev, sgt->sgl, sgt->nents, dir) == 0) {
457			num = sgt->nents;
458			goto release;
459		}
460	} else if (dobj->page) {
461		/* Single contiguous page */
462		if (sg_alloc_table(sgt, 1, GFP_KERNEL))
463			goto free_sgt;
464
465		sg_set_page(sgt->sgl, dobj->page, dobj->obj.size, 0);
466
467		if (dma_map_sg(attach->dev, sgt->sgl, sgt->nents, dir) == 0)
468			goto free_table;
469	} else if (dobj->linear) {
470		/* Single contiguous physical region - no struct page */
471		if (sg_alloc_table(sgt, 1, GFP_KERNEL))
472			goto free_sgt;
473		sg_dma_address(sgt->sgl) = dobj->dev_addr;
474		sg_dma_len(sgt->sgl) = dobj->obj.size;
475	} else {
476		goto free_sgt;
477	}
478	return sgt;
479
480 release:
481	for_each_sg(sgt->sgl, sg, num, i)
482		page_cache_release(sg_page(sg));
483 free_table:
484	sg_free_table(sgt);
485 free_sgt:
486	kfree(sgt);
487	return NULL;
488}
489
490static void armada_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
491	struct sg_table *sgt, enum dma_data_direction dir)
492{
493	struct drm_gem_object *obj = attach->dmabuf->priv;
494	struct armada_gem_object *dobj = drm_to_armada_gem(obj);
495	int i;
496
497	if (!dobj->linear)
498		dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir);
499
500	if (dobj->obj.filp) {
501		struct scatterlist *sg;
502		for_each_sg(sgt->sgl, sg, sgt->nents, i)
503			page_cache_release(sg_page(sg));
504	}
505
506	sg_free_table(sgt);
507	kfree(sgt);
508}
509
510static void *armada_gem_dmabuf_no_kmap(struct dma_buf *buf, unsigned long n)
511{
512	return NULL;
513}
514
515static void
516armada_gem_dmabuf_no_kunmap(struct dma_buf *buf, unsigned long n, void *addr)
517{
518}
519
520static int
521armada_gem_dmabuf_mmap(struct dma_buf *buf, struct vm_area_struct *vma)
522{
523	return -EINVAL;
524}
525
526static const struct dma_buf_ops armada_gem_prime_dmabuf_ops = {
527	.map_dma_buf	= armada_gem_prime_map_dma_buf,
528	.unmap_dma_buf	= armada_gem_prime_unmap_dma_buf,
529	.release	= drm_gem_dmabuf_release,
530	.kmap_atomic	= armada_gem_dmabuf_no_kmap,
531	.kunmap_atomic	= armada_gem_dmabuf_no_kunmap,
532	.kmap		= armada_gem_dmabuf_no_kmap,
533	.kunmap		= armada_gem_dmabuf_no_kunmap,
534	.mmap		= armada_gem_dmabuf_mmap,
535};
536
537struct dma_buf *
538armada_gem_prime_export(struct drm_device *dev, struct drm_gem_object *obj,
539	int flags)
540{
541	return dma_buf_export(obj, &armada_gem_prime_dmabuf_ops, obj->size,
542			      O_RDWR, NULL);
543}
544
545struct drm_gem_object *
546armada_gem_prime_import(struct drm_device *dev, struct dma_buf *buf)
547{
548	struct dma_buf_attachment *attach;
549	struct armada_gem_object *dobj;
550
551	if (buf->ops == &armada_gem_prime_dmabuf_ops) {
552		struct drm_gem_object *obj = buf->priv;
553		if (obj->dev == dev) {
554			/*
555			 * Importing our own dmabuf(s) increases the
556			 * refcount on the gem object itself.
557			 */
558			drm_gem_object_reference(obj);
559			return obj;
560		}
561	}
562
563	attach = dma_buf_attach(buf, dev->dev);
564	if (IS_ERR(attach))
565		return ERR_CAST(attach);
566
567	dobj = armada_gem_alloc_private_object(dev, buf->size);
568	if (!dobj) {
569		dma_buf_detach(buf, attach);
570		return ERR_PTR(-ENOMEM);
571	}
572
573	dobj->obj.import_attach = attach;
574	get_dma_buf(buf);
575
576	/*
577	 * Don't call dma_buf_map_attachment() here - it maps the
578	 * scatterlist immediately for DMA, and this is not always
579	 * an appropriate thing to do.
580	 */
581	return &dobj->obj;
582}
583
584int armada_gem_map_import(struct armada_gem_object *dobj)
585{
586	int ret;
587
588	dobj->sgt = dma_buf_map_attachment(dobj->obj.import_attach,
589					  DMA_TO_DEVICE);
590	if (!dobj->sgt) {
591		DRM_ERROR("dma_buf_map_attachment() returned NULL\n");
592		return -EINVAL;
593	}
594	if (IS_ERR(dobj->sgt)) {
595		ret = PTR_ERR(dobj->sgt);
596		dobj->sgt = NULL;
597		DRM_ERROR("dma_buf_map_attachment() error: %d\n", ret);
598		return ret;
599	}
600	if (dobj->sgt->nents > 1) {
601		DRM_ERROR("dma_buf_map_attachment() returned an (unsupported) scattered list\n");
602		return -EINVAL;
603	}
604	if (sg_dma_len(dobj->sgt->sgl) < dobj->obj.size) {
605		DRM_ERROR("dma_buf_map_attachment() returned a small buffer\n");
606		return -EINVAL;
607	}
608	dobj->dev_addr = sg_dma_address(dobj->sgt->sgl);
609	return 0;
610}
611