[deliverable/linux.git] / drivers / media / v4l2-core / videobuf2-dma-contig.c

/*
 * videobuf2-dma-contig.c - DMA contig memory allocator for videobuf2
 *
 * Copyright (C) 2010 Samsung Electronics
 *
 * Author: Pawel Osciak <pawel@osciak.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>

#include <media/videobuf2-core.h>
#include <media/videobuf2-dma-contig.h>
#include <media/videobuf2-memops.h>

struct vb2_dc_conf {
	struct device		*dev;
};

struct vb2_dc_buf {
	struct device			*dev;
	void				*vaddr;
	unsigned long			size;
	dma_addr_t			dma_addr;
	enum dma_data_direction		dma_dir;
	struct sg_table			*dma_sgt;

	/* MMAP related */
	struct vb2_vmarea_handler	handler;
	atomic_t			refcount;

	/* USERPTR related */
	struct vm_area_struct		*vma;
};

/*********************************************/
/*        scatterlist table functions        */
/*********************************************/


static void vb2_dc_sgt_foreach_page(struct sg_table *sgt,
	void (*cb)(struct page *pg))
{
	struct scatterlist *s;
	unsigned int i;

	for_each_sg(sgt->sgl, s, sgt->orig_nents, i) {
		struct page *page = sg_page(s);
		unsigned int n_pages = PAGE_ALIGN(s->offset + s->length)
			>> PAGE_SHIFT;
		unsigned int j;

		for (j = 0; j < n_pages; ++j, ++page)
			cb(page);
	}
}

static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt)
{
	struct scatterlist *s;
	dma_addr_t expected = sg_dma_address(sgt->sgl);
	unsigned int i;
	unsigned long size = 0;

	for_each_sg(sgt->sgl, s, sgt->nents, i) {
		if (sg_dma_address(s) != expected)
			break;
		expected = sg_dma_address(s) + sg_dma_len(s);
		size += sg_dma_len(s);
	}
	return size;
}

/*********************************************/
/*         callbacks for all buffers         */
/*********************************************/

static void *vb2_dc_cookie(void *buf_priv)
{
	struct vb2_dc_buf *buf = buf_priv;

	return &buf->dma_addr;
}

static void *vb2_dc_vaddr(void *buf_priv)
{
	struct vb2_dc_buf *buf = buf_priv;

	return buf->vaddr;
}

static unsigned int vb2_dc_num_users(void *buf_priv)
{
	struct vb2_dc_buf *buf = buf_priv;

	return atomic_read(&buf->refcount);
}

/*********************************************/
/*        callbacks for MMAP buffers         */
/*********************************************/

static void vb2_dc_put(void *buf_priv)
{
	struct vb2_dc_buf *buf = buf_priv;

	if (!atomic_dec_and_test(&buf->refcount))
		return;

	dma_free_coherent(buf->dev, buf->size, buf->vaddr, buf->dma_addr);
	kfree(buf);
}

static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size)
{
	struct vb2_dc_conf *conf = alloc_ctx;
	struct device *dev = conf->dev;
	struct vb2_dc_buf *buf;

	buf = kzalloc(sizeof *buf, GFP_KERNEL);
	if (!buf)
		return ERR_PTR(-ENOMEM);

	buf->vaddr = dma_alloc_coherent(dev, size, &buf->dma_addr, GFP_KERNEL);
	if (!buf->vaddr) {
		dev_err(dev, "dma_alloc_coherent of size %ld failed\n", size);
		kfree(buf);
		return ERR_PTR(-ENOMEM);
	}

	buf->dev = dev;
	buf->size = size;

	buf->handler.refcount = &buf->refcount;
	buf->handler.put = vb2_dc_put;
	buf->handler.arg = buf;

	atomic_inc(&buf->refcount);

	return buf;
}

static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma)
{
	struct vb2_dc_buf *buf = buf_priv;

	if (!buf) {
		printk(KERN_ERR "No buffer to map\n");
		return -EINVAL;
	}

	return vb2_mmap_pfn_range(vma, buf->dma_addr, buf->size,
				  &vb2_common_vm_ops, &buf->handler);
}

/*********************************************/
/*       callbacks for USERPTR buffers       */
/*********************************************/

static inline int vma_is_io(struct vm_area_struct *vma)
{
	return !!(vma->vm_flags & (VM_IO | VM_PFNMAP));
}

static int vb2_dc_get_user_pages(unsigned long start, struct page **pages,
	int n_pages, struct vm_area_struct *vma, int write)
{
	if (vma_is_io(vma)) {
		unsigned int i;

		for (i = 0; i < n_pages; ++i, start += PAGE_SIZE) {
			unsigned long pfn;
			int ret = follow_pfn(vma, start, &pfn);

			if (ret) {
				pr_err("no page for address %lu\n", start);
				return ret;
			}
			pages[i] = pfn_to_page(pfn);
		}
	} else {
		int n;

		n = get_user_pages(current, current->mm, start & PAGE_MASK,
			n_pages, write, 1, pages, NULL);
		/* negative error means that no page was pinned */
		n = max(n, 0);
		if (n != n_pages) {
			pr_err("got only %d of %d user pages\n", n, n_pages);
			while (n)
				put_page(pages[--n]);
			return -EFAULT;
		}
	}

	return 0;
}

static void vb2_dc_put_dirty_page(struct page *page)
{
	set_page_dirty_lock(page);
	put_page(page);
}

static void vb2_dc_put_userptr(void *buf_priv)
{
	struct vb2_dc_buf *buf = buf_priv;
	struct sg_table *sgt = buf->dma_sgt;

	dma_unmap_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir);
	if (!vma_is_io(buf->vma))
		vb2_dc_sgt_foreach_page(sgt, vb2_dc_put_dirty_page);

	sg_free_table(sgt);
	kfree(sgt);
	vb2_put_vma(buf->vma);
	kfree(buf);
}

static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr,
	unsigned long size, int write)
{
	struct vb2_dc_conf *conf = alloc_ctx;
	struct vb2_dc_buf *buf;
	unsigned long start;
	unsigned long end;
	unsigned long offset;
	struct page **pages;
	int n_pages;
	int ret = 0;
	struct vm_area_struct *vma;
	struct sg_table *sgt;
	unsigned long contig_size;

	buf = kzalloc(sizeof *buf, GFP_KERNEL);
	if (!buf)
		return ERR_PTR(-ENOMEM);

	buf->dev = conf->dev;
	buf->dma_dir = write ? DMA_FROM_DEVICE : DMA_TO_DEVICE;

	start = vaddr & PAGE_MASK;
	offset = vaddr & ~PAGE_MASK;
	end = PAGE_ALIGN(vaddr + size);
	n_pages = (end - start) >> PAGE_SHIFT;

	pages = kmalloc(n_pages * sizeof(pages[0]), GFP_KERNEL);
	if (!pages) {
		ret = -ENOMEM;
		pr_err("failed to allocate pages table\n");
		goto fail_buf;
	}

	/* current->mm->mmap_sem is taken by videobuf2 core */
	vma = find_vma(current->mm, vaddr);
	if (!vma) {
		pr_err("no vma for address %lu\n", vaddr);
		ret = -EFAULT;
		goto fail_pages;
	}

	if (vma->vm_end < vaddr + size) {
		pr_err("vma at %lu is too small for %lu bytes\n", vaddr, size);
		ret = -EFAULT;
		goto fail_pages;
	}

	buf->vma = vb2_get_vma(vma);
	if (!buf->vma) {
		pr_err("failed to copy vma\n");
		ret = -ENOMEM;
		goto fail_pages;
	}

	/* extract page list from userspace mapping */
	ret = vb2_dc_get_user_pages(start, pages, n_pages, vma, write);
	if (ret) {
		pr_err("failed to get user pages\n");
		goto fail_vma;
	}

	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
	if (!sgt) {
		pr_err("failed to allocate sg table\n");
		ret = -ENOMEM;
		goto fail_get_user_pages;
	}

	ret = sg_alloc_table_from_pages(sgt, pages, n_pages,
		offset, size, GFP_KERNEL);
	if (ret) {
		pr_err("failed to initialize sg table\n");
		goto fail_sgt;
	}

	/* pages are no longer needed */
	kfree(pages);
	pages = NULL;

	sgt->nents = dma_map_sg(buf->dev, sgt->sgl, sgt->orig_nents,
		buf->dma_dir);
	if (sgt->nents <= 0) {
		pr_err("failed to map scatterlist\n");
		ret = -EIO;
		goto fail_sgt_init;
	}

	contig_size = vb2_dc_get_contiguous_size(sgt);
	if (contig_size < size) {
		pr_err("contiguous mapping is too small %lu/%lu\n",
			contig_size, size);
		ret = -EFAULT;
		goto fail_map_sg;
	}

	buf->dma_addr = sg_dma_address(sgt->sgl);
	buf->size = size;
	buf->dma_sgt = sgt;

	return buf;

fail_map_sg:
	dma_unmap_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir);

fail_sgt_init:
	if (!vma_is_io(buf->vma))
		vb2_dc_sgt_foreach_page(sgt, put_page);
	sg_free_table(sgt);

fail_sgt:
	kfree(sgt);

fail_get_user_pages:
	if (pages && !vma_is_io(buf->vma))
		while (n_pages)
			put_page(pages[--n_pages]);

fail_vma:
	vb2_put_vma(buf->vma);

fail_pages:
	kfree(pages); /* kfree is NULL-proof */

fail_buf:
	kfree(buf);

	return ERR_PTR(ret);
}

/*********************************************/
/*       DMA CONTIG exported functions       */
/*********************************************/

const struct vb2_mem_ops vb2_dma_contig_memops = {
	.alloc		= vb2_dc_alloc,
	.put		= vb2_dc_put,
	.cookie		= vb2_dc_cookie,
	.vaddr		= vb2_dc_vaddr,
	.mmap		= vb2_dc_mmap,
	.get_userptr	= vb2_dc_get_userptr,
	.put_userptr	= vb2_dc_put_userptr,
	.num_users	= vb2_dc_num_users,
};
EXPORT_SYMBOL_GPL(vb2_dma_contig_memops);

void *vb2_dma_contig_init_ctx(struct device *dev)
{
	struct vb2_dc_conf *conf;

	conf = kzalloc(sizeof *conf, GFP_KERNEL);
	if (!conf)
		return ERR_PTR(-ENOMEM);

	conf->dev = dev;

	return conf;
}
EXPORT_SYMBOL_GPL(vb2_dma_contig_init_ctx);

void vb2_dma_contig_cleanup_ctx(void *alloc_ctx)
{
	kfree(alloc_ctx);
}
EXPORT_SYMBOL_GPL(vb2_dma_contig_cleanup_ctx);

MODULE_DESCRIPTION("DMA-contig memory handling routines for videobuf2");
MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
1a758d4e PO	1	/*
	2	* videobuf2-dma-contig.c - DMA contig memory allocator for videobuf2
	3	*
	4	* Copyright (C) 2010 Samsung Electronics
	5	*
95072084	6	* Author: Pawel Osciak <pawel@osciak.com>
1a758d4e PO	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation.
	11	*/
	12
	13	#include <linux/module.h>
e15dab75 TS	14	#include <linux/scatterlist.h>
e15dab75 TS	15	#include <linux/sched.h>
1a758d4e PO	16	#include <linux/slab.h>
	17	#include <linux/dma-mapping.h>
	18
	19	#include <media/videobuf2-core.h>
d0df3c38	20	#include <media/videobuf2-dma-contig.h>
1a758d4e PO	21	#include <media/videobuf2-memops.h>
	22
	23	struct vb2_dc_conf {
	24	struct device *dev;
	25	};
	26
	27	struct vb2_dc_buf {
72f86bff	28	struct device *dev;
1a758d4e	29	void *vaddr;
1a758d4e	30	unsigned long size;
40d8b766	31	dma_addr_t dma_addr;
e15dab75 TS	32	enum dma_data_direction dma_dir;
e15dab75 TS	33	struct sg_table *dma_sgt;
40d8b766 LP	34
40d8b766 LP	35	/* MMAP related */
1a758d4e	36	struct vb2_vmarea_handler handler;
40d8b766 LP	37	atomic_t refcount;
	38
	39	/* USERPTR related */
	40	struct vm_area_struct *vma;
1a758d4e PO	41	};
1a758d4e PO	42
e15dab75 TS	43	/*********************************************/
	44	/* scatterlist table functions */
	45	/*********************************************/
	46
	47
	48	static void vb2_dc_sgt_foreach_page(struct sg_table *sgt,
	49	void (cb)(struct page pg))
	50	{
	51	struct scatterlist *s;
	52	unsigned int i;
	53
	54	for_each_sg(sgt->sgl, s, sgt->orig_nents, i) {
	55	struct page *page = sg_page(s);
	56	unsigned int n_pages = PAGE_ALIGN(s->offset + s->length)
	57	>> PAGE_SHIFT;
	58	unsigned int j;
	59
	60	for (j = 0; j < n_pages; ++j, ++page)
	61	cb(page);
	62	}
	63	}
	64
	65	static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt)
	66	{
	67	struct scatterlist *s;
	68	dma_addr_t expected = sg_dma_address(sgt->sgl);
	69	unsigned int i;
	70	unsigned long size = 0;
	71
	72	for_each_sg(sgt->sgl, s, sgt->nents, i) {
	73	if (sg_dma_address(s) != expected)
	74	break;
	75	expected = sg_dma_address(s) + sg_dma_len(s);
	76	size += sg_dma_len(s);
	77	}
	78	return size;
	79	}
	80
40d8b766 LP	81	/*********************************************/
	82	/* callbacks for all buffers */
	83	/*********************************************/
	84
	85	static void vb2_dc_cookie(void buf_priv)
	86	{
	87	struct vb2_dc_buf *buf = buf_priv;
	88
	89	return &buf->dma_addr;
	90	}
	91
	92	static void vb2_dc_vaddr(void buf_priv)
	93	{
	94	struct vb2_dc_buf *buf = buf_priv;
	95
	96	return buf->vaddr;
	97	}
	98
	99	static unsigned int vb2_dc_num_users(void *buf_priv)
	100	{
	101	struct vb2_dc_buf *buf = buf_priv;
	102
	103	return atomic_read(&buf->refcount);
	104	}
	105
	106	/*********************************************/
	107	/* callbacks for MMAP buffers */
	108	/*********************************************/
	109
	110	static void vb2_dc_put(void *buf_priv)
	111	{
	112	struct vb2_dc_buf *buf = buf_priv;
	113
	114	if (!atomic_dec_and_test(&buf->refcount))
	115	return;
	116
	117	dma_free_coherent(buf->dev, buf->size, buf->vaddr, buf->dma_addr);
	118	kfree(buf);
	119	}
1a758d4e	120
f7f129ce	121	static void vb2_dc_alloc(void alloc_ctx, unsigned long size)
1a758d4e PO	122	{
1a758d4e PO	123	struct vb2_dc_conf *conf = alloc_ctx;
72f86bff	124	struct device *dev = conf->dev;
1a758d4e PO	125	struct vb2_dc_buf *buf;
	126
	127	buf = kzalloc(sizeof *buf, GFP_KERNEL);
	128	if (!buf)
	129	return ERR_PTR(-ENOMEM);
	130
72f86bff	131	buf->vaddr = dma_alloc_coherent(dev, size, &buf->dma_addr, GFP_KERNEL);
1a758d4e	132	if (!buf->vaddr) {
72f86bff	133	dev_err(dev, "dma_alloc_coherent of size %ld failed\n", size);
1a758d4e PO	134	kfree(buf);
	135	return ERR_PTR(-ENOMEM);
	136	}
	137
72f86bff	138	buf->dev = dev;
1a758d4e PO	139	buf->size = size;
	140
	141	buf->handler.refcount = &buf->refcount;
f7f129ce	142	buf->handler.put = vb2_dc_put;
1a758d4e PO	143	buf->handler.arg = buf;
	144
	145	atomic_inc(&buf->refcount);
	146
	147	return buf;
	148	}
	149
f7f129ce	150	static int vb2_dc_mmap(void buf_priv, struct vm_area_struct vma)
1a758d4e PO	151	{
	152	struct vb2_dc_buf *buf = buf_priv;
	153
	154	if (!buf) {
	155	printk(KERN_ERR "No buffer to map\n");
	156	return -EINVAL;
	157	}
	158
ba7fcb0c	159	return vb2_mmap_pfn_range(vma, buf->dma_addr, buf->size,
1a758d4e PO	160	&vb2_common_vm_ops, &buf->handler);
	161	}
	162
40d8b766 LP	163	/*********************************************/
	164	/* callbacks for USERPTR buffers */
	165	/*********************************************/
	166
e15dab75 TS	167	static inline int vma_is_io(struct vm_area_struct *vma)
	168	{
	169	return !!(vma->vm_flags & (VM_IO \| VM_PFNMAP));
	170	}
	171
	172	static int vb2_dc_get_user_pages(unsigned long start, struct page **pages,
	173	int n_pages, struct vm_area_struct *vma, int write)
	174	{
	175	if (vma_is_io(vma)) {
	176	unsigned int i;
	177
	178	for (i = 0; i < n_pages; ++i, start += PAGE_SIZE) {
	179	unsigned long pfn;
	180	int ret = follow_pfn(vma, start, &pfn);
	181
	182	if (ret) {
	183	pr_err("no page for address %lu\n", start);
	184	return ret;
	185	}
	186	pages[i] = pfn_to_page(pfn);
	187	}
	188	} else {
	189	int n;
	190
	191	n = get_user_pages(current, current->mm, start & PAGE_MASK,
	192	n_pages, write, 1, pages, NULL);
	193	/* negative error means that no page was pinned */
	194	n = max(n, 0);
	195	if (n != n_pages) {
	196	pr_err("got only %d of %d user pages\n", n, n_pages);
	197	while (n)
	198	put_page(pages[--n]);
	199	return -EFAULT;
	200	}
	201	}
	202
	203	return 0;
	204	}
	205
	206	static void vb2_dc_put_dirty_page(struct page *page)
	207	{
	208	set_page_dirty_lock(page);
	209	put_page(page);
	210	}
	211
	212	static void vb2_dc_put_userptr(void *buf_priv)
	213	{
	214	struct vb2_dc_buf *buf = buf_priv;
	215	struct sg_table *sgt = buf->dma_sgt;
	216
	217	dma_unmap_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir);
	218	if (!vma_is_io(buf->vma))
	219	vb2_dc_sgt_foreach_page(sgt, vb2_dc_put_dirty_page);
	220
	221	sg_free_table(sgt);
	222	kfree(sgt);
	223	vb2_put_vma(buf->vma);
	224	kfree(buf);
	225	}
	226
f7f129ce	227	static void vb2_dc_get_userptr(void alloc_ctx, unsigned long vaddr,
e15dab75	228	unsigned long size, int write)
1a758d4e	229	{
e15dab75	230	struct vb2_dc_conf *conf = alloc_ctx;
1a758d4e	231	struct vb2_dc_buf *buf;
e15dab75 TS	232	unsigned long start;
	233	unsigned long end;
	234	unsigned long offset;
	235	struct page **pages;
	236	int n_pages;
	237	int ret = 0;
1a758d4e	238	struct vm_area_struct *vma;
e15dab75 TS	239	struct sg_table *sgt;
e15dab75 TS	240	unsigned long contig_size;
1a758d4e PO	241
	242	buf = kzalloc(sizeof *buf, GFP_KERNEL);
	243	if (!buf)
	244	return ERR_PTR(-ENOMEM);
	245
e15dab75 TS	246	buf->dev = conf->dev;
	247	buf->dma_dir = write ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
	248
	249	start = vaddr & PAGE_MASK;
	250	offset = vaddr & ~PAGE_MASK;
	251	end = PAGE_ALIGN(vaddr + size);
	252	n_pages = (end - start) >> PAGE_SHIFT;
	253
	254	pages = kmalloc(n_pages * sizeof(pages[0]), GFP_KERNEL);
	255	if (!pages) {
	256	ret = -ENOMEM;
	257	pr_err("failed to allocate pages table\n");
	258	goto fail_buf;
	259	}
	260
	261	/* current->mm->mmap_sem is taken by videobuf2 core */
	262	vma = find_vma(current->mm, vaddr);
	263	if (!vma) {
	264	pr_err("no vma for address %lu\n", vaddr);
	265	ret = -EFAULT;
	266	goto fail_pages;
	267	}
	268
	269	if (vma->vm_end < vaddr + size) {
	270	pr_err("vma at %lu is too small for %lu bytes\n", vaddr, size);
	271	ret = -EFAULT;
	272	goto fail_pages;
	273	}
	274
	275	buf->vma = vb2_get_vma(vma);
	276	if (!buf->vma) {
	277	pr_err("failed to copy vma\n");
	278	ret = -ENOMEM;
	279	goto fail_pages;
	280	}
	281
	282	/* extract page list from userspace mapping */
	283	ret = vb2_dc_get_user_pages(start, pages, n_pages, vma, write);
1a758d4e	284	if (ret) {
e15dab75 TS	285	pr_err("failed to get user pages\n");
	286	goto fail_vma;
	287	}
	288
	289	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
	290	if (!sgt) {
	291	pr_err("failed to allocate sg table\n");
	292	ret = -ENOMEM;
	293	goto fail_get_user_pages;
	294	}
	295
	296	ret = sg_alloc_table_from_pages(sgt, pages, n_pages,
	297	offset, size, GFP_KERNEL);
	298	if (ret) {
	299	pr_err("failed to initialize sg table\n");
	300	goto fail_sgt;
	301	}
	302
	303	/* pages are no longer needed */
	304	kfree(pages);
	305	pages = NULL;
	306
	307	sgt->nents = dma_map_sg(buf->dev, sgt->sgl, sgt->orig_nents,
	308	buf->dma_dir);
	309	if (sgt->nents <= 0) {
	310	pr_err("failed to map scatterlist\n");
	311	ret = -EIO;
	312	goto fail_sgt_init;
	313	}
	314
	315	contig_size = vb2_dc_get_contiguous_size(sgt);
	316	if (contig_size < size) {
	317	pr_err("contiguous mapping is too small %lu/%lu\n",
	318	contig_size, size);
	319	ret = -EFAULT;
	320	goto fail_map_sg;
1a758d4e PO	321	}
1a758d4e PO	322
e15dab75	323	buf->dma_addr = sg_dma_address(sgt->sgl);
1a758d4e	324	buf->size = size;
e15dab75	325	buf->dma_sgt = sgt;
1a758d4e PO	326
1a758d4e PO	327	return buf;
1a758d4e	328
e15dab75 TS	329	fail_map_sg:
e15dab75 TS	330	dma_unmap_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir);
1a758d4e	331
e15dab75 TS	332	fail_sgt_init:
	333	if (!vma_is_io(buf->vma))
	334	vb2_dc_sgt_foreach_page(sgt, put_page);
	335	sg_free_table(sgt);
	336
	337	fail_sgt:
	338	kfree(sgt);
1a758d4e	339
e15dab75 TS	340	fail_get_user_pages:
	341	if (pages && !vma_is_io(buf->vma))
	342	while (n_pages)
	343	put_page(pages[--n_pages]);
	344
	345	fail_vma:
1a758d4e	346	vb2_put_vma(buf->vma);
e15dab75 TS	347
	348	fail_pages:
	349	kfree(pages); /* kfree is NULL-proof */
	350
	351	fail_buf:
1a758d4e	352	kfree(buf);
e15dab75 TS	353
e15dab75 TS	354	return ERR_PTR(ret);
1a758d4e PO	355	}
1a758d4e PO	356
40d8b766 LP	357	/*********************************************/
	358	/* DMA CONTIG exported functions */
	359	/*********************************************/
	360
1a758d4e	361	const struct vb2_mem_ops vb2_dma_contig_memops = {
f7f129ce LP	362	.alloc = vb2_dc_alloc,
	363	.put = vb2_dc_put,
	364	.cookie = vb2_dc_cookie,
	365	.vaddr = vb2_dc_vaddr,
	366	.mmap = vb2_dc_mmap,
	367	.get_userptr = vb2_dc_get_userptr,
	368	.put_userptr = vb2_dc_put_userptr,
	369	.num_users = vb2_dc_num_users,
1a758d4e PO	370	};
	371	EXPORT_SYMBOL_GPL(vb2_dma_contig_memops);
	372
	373	void vb2_dma_contig_init_ctx(struct device dev)
	374	{
	375	struct vb2_dc_conf *conf;
	376
	377	conf = kzalloc(sizeof *conf, GFP_KERNEL);
	378	if (!conf)
	379	return ERR_PTR(-ENOMEM);
	380
	381	conf->dev = dev;
	382
	383	return conf;
	384	}
	385	EXPORT_SYMBOL_GPL(vb2_dma_contig_init_ctx);
	386
	387	void vb2_dma_contig_cleanup_ctx(void *alloc_ctx)
	388	{
	389	kfree(alloc_ctx);
	390	}
	391	EXPORT_SYMBOL_GPL(vb2_dma_contig_cleanup_ctx);
	392
	393	MODULE_DESCRIPTION("DMA-contig memory handling routines for videobuf2");
95072084	394	MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
1a758d4e	395	MODULE_LICENSE("GPL");