[deliverable/linux.git] / drivers / media / video / 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/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 vb2_dc_conf		*conf;
	void				*vaddr;
	dma_addr_t			dma_addr;
	unsigned long			size;
	struct vm_area_struct		*vma;
	atomic_t			refcount;
	struct vb2_vmarea_handler	handler;
};

static void vb2_dma_contig_put(void *buf_priv);

static void *vb2_dma_contig_alloc(void *alloc_ctx, unsigned long size)
{
	struct vb2_dc_conf *conf = alloc_ctx;
	struct vb2_dc_buf *buf;

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

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

	buf->conf = conf;
	buf->size = size;

	buf->handler.refcount = &buf->refcount;
	buf->handler.put = vb2_dma_contig_put;
	buf->handler.arg = buf;

	atomic_inc(&buf->refcount);

	return buf;
}

static void vb2_dma_contig_put(void *buf_priv)
{
	struct vb2_dc_buf *buf = buf_priv;

	if (atomic_dec_and_test(&buf->refcount)) {
		dma_free_coherent(buf->conf->dev, buf->size, buf->vaddr,
				  buf->dma_addr);
		kfree(buf);
	}
}

static void *vb2_dma_contig_cookie(void *buf_priv)
{
	struct vb2_dc_buf *buf = buf_priv;

	return &buf->dma_addr;
}

static void *vb2_dma_contig_vaddr(void *buf_priv)
{
	struct vb2_dc_buf *buf = buf_priv;
	if (!buf)
		return NULL;

	return buf->vaddr;
}

static unsigned int vb2_dma_contig_num_users(void *buf_priv)
{
	struct vb2_dc_buf *buf = buf_priv;

	return atomic_read(&buf->refcount);
}

static int vb2_dma_contig_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);
}

static void *vb2_dma_contig_get_userptr(void *alloc_ctx, unsigned long vaddr,
					unsigned long size, int write)
{
	struct vb2_dc_buf *buf;
	struct vm_area_struct *vma;
	dma_addr_t dma_addr = 0;
	int ret;

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

	ret = vb2_get_contig_userptr(vaddr, size, &vma, &dma_addr);
	if (ret) {
		printk(KERN_ERR "Failed acquiring VMA for vaddr 0x%08lx\n",
				vaddr);
		kfree(buf);
		return ERR_PTR(ret);
	}

	buf->size = size;
	buf->dma_addr = dma_addr;
	buf->vma = vma;

	return buf;
}

static void vb2_dma_contig_put_userptr(void *mem_priv)
{
	struct vb2_dc_buf *buf = mem_priv;

	if (!buf)
		return;

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

const struct vb2_mem_ops vb2_dma_contig_memops = {
	.alloc		= vb2_dma_contig_alloc,
	.put		= vb2_dma_contig_put,
	.cookie		= vb2_dma_contig_cookie,
	.vaddr		= vb2_dma_contig_vaddr,
	.mmap		= vb2_dma_contig_mmap,
	.get_userptr	= vb2_dma_contig_get_userptr,
	.put_userptr	= vb2_dma_contig_put_userptr,
	.num_users	= vb2_dma_contig_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>
	14	#include <linux/slab.h>
	15	#include <linux/dma-mapping.h>
	16
	17	#include <media/videobuf2-core.h>
f36c7d9e	18	#include <media/videobuf2-dma-contig.h>
1a758d4e PO	19	#include <media/videobuf2-memops.h>
	20
	21	struct vb2_dc_conf {
	22	struct device *dev;
	23	};
	24
	25	struct vb2_dc_buf {
	26	struct vb2_dc_conf *conf;
	27	void *vaddr;
ba7fcb0c	28	dma_addr_t dma_addr;
1a758d4e PO	29	unsigned long size;
	30	struct vm_area_struct *vma;
	31	atomic_t refcount;
	32	struct vb2_vmarea_handler handler;
	33	};
	34
	35	static void vb2_dma_contig_put(void *buf_priv);
	36
	37	static void vb2_dma_contig_alloc(void alloc_ctx, unsigned long size)
	38	{
	39	struct vb2_dc_conf *conf = alloc_ctx;
	40	struct vb2_dc_buf *buf;
	41
	42	buf = kzalloc(sizeof *buf, GFP_KERNEL);
	43	if (!buf)
	44	return ERR_PTR(-ENOMEM);
	45
ba7fcb0c	46	buf->vaddr = dma_alloc_coherent(conf->dev, size, &buf->dma_addr,
1a758d4e PO	47	GFP_KERNEL);
	48	if (!buf->vaddr) {
	49	dev_err(conf->dev, "dma_alloc_coherent of size %ld failed\n",
99a41771	50	size);
1a758d4e PO	51	kfree(buf);
	52	return ERR_PTR(-ENOMEM);
	53	}
	54
	55	buf->conf = conf;
	56	buf->size = size;
	57
	58	buf->handler.refcount = &buf->refcount;
	59	buf->handler.put = vb2_dma_contig_put;
	60	buf->handler.arg = buf;
	61
	62	atomic_inc(&buf->refcount);
	63
	64	return buf;
	65	}
	66
	67	static void vb2_dma_contig_put(void *buf_priv)
	68	{
	69	struct vb2_dc_buf *buf = buf_priv;
	70
	71	if (atomic_dec_and_test(&buf->refcount)) {
	72	dma_free_coherent(buf->conf->dev, buf->size, buf->vaddr,
ba7fcb0c	73	buf->dma_addr);
1a758d4e PO	74	kfree(buf);
	75	}
	76	}
	77
	78	static void vb2_dma_contig_cookie(void buf_priv)
	79	{
	80	struct vb2_dc_buf *buf = buf_priv;
	81
ba7fcb0c	82	return &buf->dma_addr;
1a758d4e PO	83	}
	84
	85	static void vb2_dma_contig_vaddr(void buf_priv)
	86	{
	87	struct vb2_dc_buf *buf = buf_priv;
	88	if (!buf)
8106a390	89	return NULL;
1a758d4e PO	90
	91	return buf->vaddr;
	92	}
	93
	94	static unsigned int vb2_dma_contig_num_users(void *buf_priv)
	95	{
	96	struct vb2_dc_buf *buf = buf_priv;
	97
	98	return atomic_read(&buf->refcount);
	99	}
	100
	101	static int vb2_dma_contig_mmap(void buf_priv, struct vm_area_struct vma)
	102	{
	103	struct vb2_dc_buf *buf = buf_priv;
	104
	105	if (!buf) {
	106	printk(KERN_ERR "No buffer to map\n");
	107	return -EINVAL;
	108	}
	109
ba7fcb0c	110	return vb2_mmap_pfn_range(vma, buf->dma_addr, buf->size,
1a758d4e PO	111	&vb2_common_vm_ops, &buf->handler);
	112	}
	113
	114	static void vb2_dma_contig_get_userptr(void alloc_ctx, unsigned long vaddr,
	115	unsigned long size, int write)
	116	{
	117	struct vb2_dc_buf *buf;
	118	struct vm_area_struct *vma;
ba7fcb0c	119	dma_addr_t dma_addr = 0;
1a758d4e PO	120	int ret;
	121
	122	buf = kzalloc(sizeof *buf, GFP_KERNEL);
	123	if (!buf)
	124	return ERR_PTR(-ENOMEM);
	125
ba7fcb0c	126	ret = vb2_get_contig_userptr(vaddr, size, &vma, &dma_addr);
1a758d4e PO	127	if (ret) {
	128	printk(KERN_ERR "Failed acquiring VMA for vaddr 0x%08lx\n",
	129	vaddr);
	130	kfree(buf);
	131	return ERR_PTR(ret);
	132	}
	133
	134	buf->size = size;
ba7fcb0c	135	buf->dma_addr = dma_addr;
1a758d4e PO	136	buf->vma = vma;
	137
	138	return buf;
	139	}
	140
	141	static void vb2_dma_contig_put_userptr(void *mem_priv)
	142	{
	143	struct vb2_dc_buf *buf = mem_priv;
	144
	145	if (!buf)
	146	return;
	147
	148	vb2_put_vma(buf->vma);
	149	kfree(buf);
	150	}
	151
	152	const struct vb2_mem_ops vb2_dma_contig_memops = {
	153	.alloc = vb2_dma_contig_alloc,
	154	.put = vb2_dma_contig_put,
	155	.cookie = vb2_dma_contig_cookie,
	156	.vaddr = vb2_dma_contig_vaddr,
	157	.mmap = vb2_dma_contig_mmap,
	158	.get_userptr = vb2_dma_contig_get_userptr,
	159	.put_userptr = vb2_dma_contig_put_userptr,
	160	.num_users = vb2_dma_contig_num_users,
	161	};
	162	EXPORT_SYMBOL_GPL(vb2_dma_contig_memops);
	163
	164	void vb2_dma_contig_init_ctx(struct device dev)
	165	{
	166	struct vb2_dc_conf *conf;
	167
	168	conf = kzalloc(sizeof *conf, GFP_KERNEL);
	169	if (!conf)
	170	return ERR_PTR(-ENOMEM);
	171
	172	conf->dev = dev;
	173
	174	return conf;
	175	}
	176	EXPORT_SYMBOL_GPL(vb2_dma_contig_init_ctx);
	177
	178	void vb2_dma_contig_cleanup_ctx(void *alloc_ctx)
	179	{
	180	kfree(alloc_ctx);
	181	}
	182	EXPORT_SYMBOL_GPL(vb2_dma_contig_cleanup_ctx);
	183
	184	MODULE_DESCRIPTION("DMA-contig memory handling routines for videobuf2");
95072084	185	MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
1a758d4e	186	MODULE_LICENSE("GPL");