[linux-2.6-block.git] / drivers / media / v4l2-core / videobuf2-vmalloc.c

/*
 * videobuf2-vmalloc.c - vmalloc 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/io.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>

#include <media/videobuf2-v4l2.h>
#include <media/videobuf2-vmalloc.h>
#include <media/videobuf2-memops.h>

struct vb2_vmalloc_buf {
	void				*vaddr;
	struct frame_vector		*vec;
	enum dma_data_direction		dma_dir;
	unsigned long			size;
	atomic_t			refcount;
	struct vb2_vmarea_handler	handler;
	struct dma_buf			*dbuf;
};

static void vb2_vmalloc_put(void *buf_priv);

static void *vb2_vmalloc_alloc(struct device *dev, unsigned long attrs,
			       unsigned long size, enum dma_data_direction dma_dir,
			       gfp_t gfp_flags)
{
	struct vb2_vmalloc_buf *buf;

	buf = kzalloc(sizeof(*buf), GFP_KERNEL | gfp_flags);
	if (!buf)
		return NULL;

	buf->size = size;
	buf->vaddr = vmalloc_user(buf->size);
	buf->dma_dir = dma_dir;
	buf->handler.refcount = &buf->refcount;
	buf->handler.put = vb2_vmalloc_put;
	buf->handler.arg = buf;

	if (!buf->vaddr) {
		pr_debug("vmalloc of size %ld failed\n", buf->size);
		kfree(buf);
		return NULL;
	}

	atomic_inc(&buf->refcount);
	return buf;
}

static void vb2_vmalloc_put(void *buf_priv)
{
	struct vb2_vmalloc_buf *buf = buf_priv;

	if (atomic_dec_and_test(&buf->refcount)) {
		vfree(buf->vaddr);
		kfree(buf);
	}
}

static void *vb2_vmalloc_get_userptr(struct device *dev, unsigned long vaddr,
				     unsigned long size,
				     enum dma_data_direction dma_dir)
{
	struct vb2_vmalloc_buf *buf;
	struct frame_vector *vec;
	int n_pages, offset, i;

	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
	if (!buf)
		return NULL;

	buf->dma_dir = dma_dir;
	offset = vaddr & ~PAGE_MASK;
	buf->size = size;
	vec = vb2_create_framevec(vaddr, size, dma_dir == DMA_FROM_DEVICE);
	if (IS_ERR(vec))
		goto fail_pfnvec_create;
	buf->vec = vec;
	n_pages = frame_vector_count(vec);
	if (frame_vector_to_pages(vec) < 0) {
		unsigned long *nums = frame_vector_pfns(vec);

		/*
		 * We cannot get page pointers for these pfns. Check memory is
		 * physically contiguous and use direct mapping.
		 */
		for (i = 1; i < n_pages; i++)
			if (nums[i-1] + 1 != nums[i])
				goto fail_map;
		buf->vaddr = (__force void *)
				ioremap_nocache(nums[0] << PAGE_SHIFT, size);
	} else {
		buf->vaddr = vm_map_ram(frame_vector_pages(vec), n_pages, -1,
					PAGE_KERNEL);
	}

	if (!buf->vaddr)
		goto fail_map;
	buf->vaddr += offset;
	return buf;

fail_map:
	vb2_destroy_framevec(vec);
fail_pfnvec_create:
	kfree(buf);

	return NULL;
}

static void vb2_vmalloc_put_userptr(void *buf_priv)
{
	struct vb2_vmalloc_buf *buf = buf_priv;
	unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK;
	unsigned int i;
	struct page **pages;
	unsigned int n_pages;

	if (!buf->vec->is_pfns) {
		n_pages = frame_vector_count(buf->vec);
		pages = frame_vector_pages(buf->vec);
		if (vaddr)
			vm_unmap_ram((void *)vaddr, n_pages);
		if (buf->dma_dir == DMA_FROM_DEVICE)
			for (i = 0; i < n_pages; i++)
				set_page_dirty_lock(pages[i]);
	} else {
		iounmap((__force void __iomem *)buf->vaddr);
	}
	vb2_destroy_framevec(buf->vec);
	kfree(buf);
}

static void *vb2_vmalloc_vaddr(void *buf_priv)
{
	struct vb2_vmalloc_buf *buf = buf_priv;

	if (!buf->vaddr) {
		pr_err("Address of an unallocated plane requested "
		       "or cannot map user pointer\n");
		return NULL;
	}

	return buf->vaddr;
}

static unsigned int vb2_vmalloc_num_users(void *buf_priv)
{
	struct vb2_vmalloc_buf *buf = buf_priv;
	return atomic_read(&buf->refcount);
}

static int vb2_vmalloc_mmap(void *buf_priv, struct vm_area_struct *vma)
{
	struct vb2_vmalloc_buf *buf = buf_priv;
	int ret;

	if (!buf) {
		pr_err("No memory to map\n");
		return -EINVAL;
	}

	ret = remap_vmalloc_range(vma, buf->vaddr, 0);
	if (ret) {
		pr_err("Remapping vmalloc memory, error: %d\n", ret);
		return ret;
	}

	/*
	 * Make sure that vm_areas for 2 buffers won't be merged together
	 */
	vma->vm_flags		|= VM_DONTEXPAND;

	/*
	 * Use common vm_area operations to track buffer refcount.
	 */
	vma->vm_private_data	= &buf->handler;
	vma->vm_ops		= &vb2_common_vm_ops;

	vma->vm_ops->open(vma);

	return 0;
}

#ifdef CONFIG_HAS_DMA
/*********************************************/
/*         DMABUF ops for exporters          */
/*********************************************/

struct vb2_vmalloc_attachment {
	struct sg_table sgt;
	enum dma_data_direction dma_dir;
};

static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev,
	struct dma_buf_attachment *dbuf_attach)
{
	struct vb2_vmalloc_attachment *attach;
	struct vb2_vmalloc_buf *buf = dbuf->priv;
	int num_pages = PAGE_ALIGN(buf->size) / PAGE_SIZE;
	struct sg_table *sgt;
	struct scatterlist *sg;
	void *vaddr = buf->vaddr;
	int ret;
	int i;

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

	sgt = &attach->sgt;
	ret = sg_alloc_table(sgt, num_pages, GFP_KERNEL);
	if (ret) {
		kfree(attach);
		return ret;
	}
	for_each_sg(sgt->sgl, sg, sgt->nents, i) {
		struct page *page = vmalloc_to_page(vaddr);

		if (!page) {
			sg_free_table(sgt);
			kfree(attach);
			return -ENOMEM;
		}
		sg_set_page(sg, page, PAGE_SIZE, 0);
		vaddr += PAGE_SIZE;
	}

	attach->dma_dir = DMA_NONE;
	dbuf_attach->priv = attach;
	return 0;
}

static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf *dbuf,
	struct dma_buf_attachment *db_attach)
{
	struct vb2_vmalloc_attachment *attach = db_attach->priv;
	struct sg_table *sgt;

	if (!attach)
		return;

	sgt = &attach->sgt;

	/* release the scatterlist cache */
	if (attach->dma_dir != DMA_NONE)
		dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
			attach->dma_dir);
	sg_free_table(sgt);
	kfree(attach);
	db_attach->priv = NULL;
}

static struct sg_table *vb2_vmalloc_dmabuf_ops_map(
	struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir)
{
	struct vb2_vmalloc_attachment *attach = db_attach->priv;
	/* stealing dmabuf mutex to serialize map/unmap operations */
	struct mutex *lock = &db_attach->dmabuf->lock;
	struct sg_table *sgt;

	mutex_lock(lock);

	sgt = &attach->sgt;
	/* return previously mapped sg table */
	if (attach->dma_dir == dma_dir) {
		mutex_unlock(lock);
		return sgt;
	}

	/* release any previous cache */
	if (attach->dma_dir != DMA_NONE) {
		dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
			attach->dma_dir);
		attach->dma_dir = DMA_NONE;
	}

	/* mapping to the client with new direction */
	sgt->nents = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
				dma_dir);
	if (!sgt->nents) {
		pr_err("failed to map scatterlist\n");
		mutex_unlock(lock);
		return ERR_PTR(-EIO);
	}

	attach->dma_dir = dma_dir;

	mutex_unlock(lock);

	return sgt;
}

static void vb2_vmalloc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach,
	struct sg_table *sgt, enum dma_data_direction dma_dir)
{
	/* nothing to be done here */
}

static void vb2_vmalloc_dmabuf_ops_release(struct dma_buf *dbuf)
{
	/* drop reference obtained in vb2_vmalloc_get_dmabuf */
	vb2_vmalloc_put(dbuf->priv);
}

static void *vb2_vmalloc_dmabuf_ops_kmap(struct dma_buf *dbuf, unsigned long pgnum)
{
	struct vb2_vmalloc_buf *buf = dbuf->priv;

	return buf->vaddr + pgnum * PAGE_SIZE;
}

static void *vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf *dbuf)
{
	struct vb2_vmalloc_buf *buf = dbuf->priv;

	return buf->vaddr;
}

static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf,
	struct vm_area_struct *vma)
{
	return vb2_vmalloc_mmap(dbuf->priv, vma);
}

static struct dma_buf_ops vb2_vmalloc_dmabuf_ops = {
	.attach = vb2_vmalloc_dmabuf_ops_attach,
	.detach = vb2_vmalloc_dmabuf_ops_detach,
	.map_dma_buf = vb2_vmalloc_dmabuf_ops_map,
	.unmap_dma_buf = vb2_vmalloc_dmabuf_ops_unmap,
	.kmap = vb2_vmalloc_dmabuf_ops_kmap,
	.kmap_atomic = vb2_vmalloc_dmabuf_ops_kmap,
	.vmap = vb2_vmalloc_dmabuf_ops_vmap,
	.mmap = vb2_vmalloc_dmabuf_ops_mmap,
	.release = vb2_vmalloc_dmabuf_ops_release,
};

static struct dma_buf *vb2_vmalloc_get_dmabuf(void *buf_priv, unsigned long flags)
{
	struct vb2_vmalloc_buf *buf = buf_priv;
	struct dma_buf *dbuf;
	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);

	exp_info.ops = &vb2_vmalloc_dmabuf_ops;
	exp_info.size = buf->size;
	exp_info.flags = flags;
	exp_info.priv = buf;

	if (WARN_ON(!buf->vaddr))
		return NULL;

	dbuf = dma_buf_export(&exp_info);
	if (IS_ERR(dbuf))
		return NULL;

	/* dmabuf keeps reference to vb2 buffer */
	atomic_inc(&buf->refcount);

	return dbuf;
}
#endif /* CONFIG_HAS_DMA */


/*********************************************/
/*       callbacks for DMABUF buffers        */
/*********************************************/

static int vb2_vmalloc_map_dmabuf(void *mem_priv)
{
	struct vb2_vmalloc_buf *buf = mem_priv;

	buf->vaddr = dma_buf_vmap(buf->dbuf);

	return buf->vaddr ? 0 : -EFAULT;
}

static void vb2_vmalloc_unmap_dmabuf(void *mem_priv)
{
	struct vb2_vmalloc_buf *buf = mem_priv;

	dma_buf_vunmap(buf->dbuf, buf->vaddr);
	buf->vaddr = NULL;
}

static void vb2_vmalloc_detach_dmabuf(void *mem_priv)
{
	struct vb2_vmalloc_buf *buf = mem_priv;

	if (buf->vaddr)
		dma_buf_vunmap(buf->dbuf, buf->vaddr);

	kfree(buf);
}

static void *vb2_vmalloc_attach_dmabuf(struct device *dev, struct dma_buf *dbuf,
	unsigned long size, enum dma_data_direction dma_dir)
{
	struct vb2_vmalloc_buf *buf;

	if (dbuf->size < size)
		return ERR_PTR(-EFAULT);

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

	buf->dbuf = dbuf;
	buf->dma_dir = dma_dir;
	buf->size = size;

	return buf;
}


const struct vb2_mem_ops vb2_vmalloc_memops = {
	.alloc		= vb2_vmalloc_alloc,
	.put		= vb2_vmalloc_put,
	.get_userptr	= vb2_vmalloc_get_userptr,
	.put_userptr	= vb2_vmalloc_put_userptr,
#ifdef CONFIG_HAS_DMA
	.get_dmabuf	= vb2_vmalloc_get_dmabuf,
#endif
	.map_dmabuf	= vb2_vmalloc_map_dmabuf,
	.unmap_dmabuf	= vb2_vmalloc_unmap_dmabuf,
	.attach_dmabuf	= vb2_vmalloc_attach_dmabuf,
	.detach_dmabuf	= vb2_vmalloc_detach_dmabuf,
	.vaddr		= vb2_vmalloc_vaddr,
	.mmap		= vb2_vmalloc_mmap,
	.num_users	= vb2_vmalloc_num_users,
};
EXPORT_SYMBOL_GPL(vb2_vmalloc_memops);

MODULE_DESCRIPTION("vmalloc memory handling routines for videobuf2");
MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
3c18ff06 PO	1	/*
	2	* videobuf2-vmalloc.c - vmalloc memory allocator for videobuf2
	3	*
	4	* Copyright (C) 2010 Samsung Electronics
	5	*
95072084	6	* Author: Pawel Osciak <pawel@osciak.com>
3c18ff06 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
570d2a48	13	#include <linux/io.h>
3c18ff06 PO	14	#include <linux/module.h>
3c18ff06 PO	15	#include <linux/mm.h>
4419b8ac	16	#include <linux/sched.h>
3c18ff06 PO	17	#include <linux/slab.h>
	18	#include <linux/vmalloc.h>
	19
c139990e	20	#include <media/videobuf2-v4l2.h>
ddb9fa25	21	#include <media/videobuf2-vmalloc.h>
3c18ff06 PO	22	#include <media/videobuf2-memops.h>
	23
	24	struct vb2_vmalloc_buf {
	25	void *vaddr;
5a9e4dec	26	struct frame_vector *vec;
cd474037	27	enum dma_data_direction dma_dir;
3c18ff06 PO	28	unsigned long size;
	29	atomic_t refcount;
	30	struct vb2_vmarea_handler handler;
89d2ee08	31	struct dma_buf *dbuf;
3c18ff06 PO	32	};
	33
	34	static void vb2_vmalloc_put(void *buf_priv);
	35
00085f1e	36	static void vb2_vmalloc_alloc(struct device dev, unsigned long attrs,
d16e832d HV	37	unsigned long size, enum dma_data_direction dma_dir,
d16e832d HV	38	gfp_t gfp_flags)
3c18ff06 PO	39	{
	40	struct vb2_vmalloc_buf *buf;
	41
b6ba2057	42	buf = kzalloc(sizeof(*buf), GFP_KERNEL \| gfp_flags);
3c18ff06 PO	43	if (!buf)
	44	return NULL;
	45
	46	buf->size = size;
	47	buf->vaddr = vmalloc_user(buf->size);
d935c57e	48	buf->dma_dir = dma_dir;
3c18ff06 PO	49	buf->handler.refcount = &buf->refcount;
	50	buf->handler.put = vb2_vmalloc_put;
	51	buf->handler.arg = buf;
	52
	53	if (!buf->vaddr) {
4419b8ac	54	pr_debug("vmalloc of size %ld failed\n", buf->size);
3c18ff06 PO	55	kfree(buf);
	56	return NULL;
	57	}
	58
	59	atomic_inc(&buf->refcount);
3c18ff06 PO	60	return buf;
	61	}
	62
	63	static void vb2_vmalloc_put(void *buf_priv)
	64	{
	65	struct vb2_vmalloc_buf *buf = buf_priv;
	66
	67	if (atomic_dec_and_test(&buf->refcount)) {
3c18ff06 PO	68	vfree(buf->vaddr);
	69	kfree(buf);
	70	}
	71	}
	72
36c0f8b3	73	static void vb2_vmalloc_get_userptr(struct device dev, unsigned long vaddr,
cd474037 HV	74	unsigned long size,
cd474037 HV	75	enum dma_data_direction dma_dir)
4419b8ac AP	76	{
4419b8ac AP	77	struct vb2_vmalloc_buf *buf;
5a9e4dec JK	78	struct frame_vector *vec;
5a9e4dec JK	79	int n_pages, offset, i;
4419b8ac AP	80
	81	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
	82	if (!buf)
	83	return NULL;
	84
cd474037	85	buf->dma_dir = dma_dir;
4419b8ac AP	86	offset = vaddr & ~PAGE_MASK;
4419b8ac AP	87	buf->size = size;
5a9e4dec JK	88	vec = vb2_create_framevec(vaddr, size, dma_dir == DMA_FROM_DEVICE);
	89	if (IS_ERR(vec))
	90	goto fail_pfnvec_create;
	91	buf->vec = vec;
	92	n_pages = frame_vector_count(vec);
	93	if (frame_vector_to_pages(vec) < 0) {
	94	unsigned long *nums = frame_vector_pfns(vec);
	95
	96	/*
	97	* We cannot get page pointers for these pfns. Check memory is
	98	* physically contiguous and use direct mapping.
	99	*/
	100	for (i = 1; i < n_pages; i++)
	101	if (nums[i-1] + 1 != nums[i])
	102	goto fail_map;
	103	buf->vaddr = (__force void *)
	104	ioremap_nocache(nums[0] << PAGE_SHIFT, size);
570d2a48	105	} else {
5a9e4dec	106	buf->vaddr = vm_map_ram(frame_vector_pages(vec), n_pages, -1,
570d2a48	107	PAGE_KERNEL);
570d2a48	108	}
4419b8ac	109
5a9e4dec JK	110	if (!buf->vaddr)
5a9e4dec JK	111	goto fail_map;
4419b8ac AP	112	buf->vaddr += offset;
	113	return buf;
	114
5a9e4dec JK	115	fail_map:
	116	vb2_destroy_framevec(vec);
	117	fail_pfnvec_create:
4419b8ac AP	118	kfree(buf);
	119
	120	return NULL;
	121	}
	122
	123	static void vb2_vmalloc_put_userptr(void *buf_priv)
3c18ff06 PO	124	{
3c18ff06 PO	125	struct vb2_vmalloc_buf *buf = buf_priv;
4419b8ac AP	126	unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK;
4419b8ac AP	127	unsigned int i;
5a9e4dec JK	128	struct page **pages;
5a9e4dec JK	129	unsigned int n_pages;
4419b8ac	130
5a9e4dec JK	131	if (!buf->vec->is_pfns) {
	132	n_pages = frame_vector_count(buf->vec);
	133	pages = frame_vector_pages(buf->vec);
570d2a48	134	if (vaddr)
5a9e4dec JK	135	vm_unmap_ram((void *)vaddr, n_pages);
	136	if (buf->dma_dir == DMA_FROM_DEVICE)
	137	for (i = 0; i < n_pages; i++)
	138	set_page_dirty_lock(pages[i]);
570d2a48	139	} else {
7c424dd1	140	iounmap((__force void __iomem *)buf->vaddr);
4419b8ac	141	}
5a9e4dec	142	vb2_destroy_framevec(buf->vec);
4419b8ac AP	143	kfree(buf);
4419b8ac AP	144	}
3c18ff06	145
4419b8ac AP	146	static void vb2_vmalloc_vaddr(void buf_priv)
	147	{
	148	struct vb2_vmalloc_buf *buf = buf_priv;
3c18ff06 PO	149
3c18ff06 PO	150	if (!buf->vaddr) {
4419b8ac AP	151	pr_err("Address of an unallocated plane requested "
4419b8ac AP	152	"or cannot map user pointer\n");
3c18ff06 PO	153	return NULL;
	154	}
	155
	156	return buf->vaddr;
	157	}
	158
	159	static unsigned int vb2_vmalloc_num_users(void *buf_priv)
	160	{
	161	struct vb2_vmalloc_buf *buf = buf_priv;
	162	return atomic_read(&buf->refcount);
	163	}
	164
	165	static int vb2_vmalloc_mmap(void buf_priv, struct vm_area_struct vma)
	166	{
	167	struct vb2_vmalloc_buf *buf = buf_priv;
	168	int ret;
	169
	170	if (!buf) {
4419b8ac	171	pr_err("No memory to map\n");
3c18ff06 PO	172	return -EINVAL;
	173	}
	174
	175	ret = remap_vmalloc_range(vma, buf->vaddr, 0);
	176	if (ret) {
4419b8ac	177	pr_err("Remapping vmalloc memory, error: %d\n", ret);
3c18ff06 PO	178	return ret;
	179	}
	180
	181	/*
	182	* Make sure that vm_areas for 2 buffers won't be merged together
	183	*/
	184	vma->vm_flags \|= VM_DONTEXPAND;
	185
	186	/*
	187	* Use common vm_area operations to track buffer refcount.
	188	*/
	189	vma->vm_private_data = &buf->handler;
	190	vma->vm_ops = &vb2_common_vm_ops;
	191
	192	vma->vm_ops->open(vma);
	193
	194	return 0;
	195	}
	196
99f3cd52	197	#ifdef CONFIG_HAS_DMA
46506350 HV	198	/*********************************************/
	199	/* DMABUF ops for exporters */
	200	/*********************************************/
	201
	202	struct vb2_vmalloc_attachment {
	203	struct sg_table sgt;
	204	enum dma_data_direction dma_dir;
	205	};
	206
	207	static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf dbuf, struct device dev,
	208	struct dma_buf_attachment *dbuf_attach)
	209	{
	210	struct vb2_vmalloc_attachment *attach;
	211	struct vb2_vmalloc_buf *buf = dbuf->priv;
	212	int num_pages = PAGE_ALIGN(buf->size) / PAGE_SIZE;
	213	struct sg_table *sgt;
	214	struct scatterlist *sg;
	215	void *vaddr = buf->vaddr;
	216	int ret;
	217	int i;
	218
	219	attach = kzalloc(sizeof(*attach), GFP_KERNEL);
	220	if (!attach)
	221	return -ENOMEM;
	222
	223	sgt = &attach->sgt;
	224	ret = sg_alloc_table(sgt, num_pages, GFP_KERNEL);
	225	if (ret) {
	226	kfree(attach);
	227	return ret;
	228	}
	229	for_each_sg(sgt->sgl, sg, sgt->nents, i) {
	230	struct page *page = vmalloc_to_page(vaddr);
	231
	232	if (!page) {
	233	sg_free_table(sgt);
	234	kfree(attach);
	235	return -ENOMEM;
	236	}
	237	sg_set_page(sg, page, PAGE_SIZE, 0);
	238	vaddr += PAGE_SIZE;
	239	}
	240
	241	attach->dma_dir = DMA_NONE;
	242	dbuf_attach->priv = attach;
	243	return 0;
	244	}
	245
	246	static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf *dbuf,
	247	struct dma_buf_attachment *db_attach)
	248	{
	249	struct vb2_vmalloc_attachment *attach = db_attach->priv;
	250	struct sg_table *sgt;
	251
	252	if (!attach)
	253	return;
	254
	255	sgt = &attach->sgt;
	256
	257	/* release the scatterlist cache */
	258	if (attach->dma_dir != DMA_NONE)
	259	dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
	260	attach->dma_dir);
	261	sg_free_table(sgt);
262	kfree(attach);
263	db_attach->priv = NULL;
264	}
265
266	static struct sg_table *vb2_vmalloc_dmabuf_ops_map(
267	struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir)
268	{
269	struct vb2_vmalloc_attachment *attach = db_attach->priv;
270	/* stealing dmabuf mutex to serialize map/unmap operations */
271	struct mutex *lock = &db_attach->dmabuf->lock;
272	struct sg_table *sgt;
46506350 HV	273
	274	mutex_lock(lock);
	275
	276	sgt = &attach->sgt;
	277	/* return previously mapped sg table */
	278	if (attach->dma_dir == dma_dir) {
	279	mutex_unlock(lock);
	280	return sgt;
	281	}
	282
	283	/* release any previous cache */
	284	if (attach->dma_dir != DMA_NONE) {
	285	dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
	286	attach->dma_dir);
	287	attach->dma_dir = DMA_NONE;
	288	}
	289
	290	/* mapping to the client with new direction */
ba81c6ed RR	291	sgt->nents = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
	292	dma_dir);
	293	if (!sgt->nents) {
46506350 HV	294	pr_err("failed to map scatterlist\n");
	295	mutex_unlock(lock);
	296	return ERR_PTR(-EIO);
	297	}
	298
	299	attach->dma_dir = dma_dir;
	300
	301	mutex_unlock(lock);
	302
	303	return sgt;
	304	}
	305
	306	static void vb2_vmalloc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach,
	307	struct sg_table *sgt, enum dma_data_direction dma_dir)
	308	{
	309	/* nothing to be done here */
	310	}
	311
	312	static void vb2_vmalloc_dmabuf_ops_release(struct dma_buf *dbuf)
	313	{
	314	/* drop reference obtained in vb2_vmalloc_get_dmabuf */
	315	vb2_vmalloc_put(dbuf->priv);
	316	}
	317
	318	static void vb2_vmalloc_dmabuf_ops_kmap(struct dma_buf dbuf, unsigned long pgnum)
	319	{
	320	struct vb2_vmalloc_buf *buf = dbuf->priv;
	321
	322	return buf->vaddr + pgnum * PAGE_SIZE;
	323	}
	324
	325	static void vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf dbuf)
	326	{
	327	struct vb2_vmalloc_buf *buf = dbuf->priv;
	328
	329	return buf->vaddr;
	330	}
	331
	332	static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf,
	333	struct vm_area_struct *vma)
	334	{
	335	return vb2_vmalloc_mmap(dbuf->priv, vma);
	336	}
	337
	338	static struct dma_buf_ops vb2_vmalloc_dmabuf_ops = {
	339	.attach = vb2_vmalloc_dmabuf_ops_attach,
	340	.detach = vb2_vmalloc_dmabuf_ops_detach,
	341	.map_dma_buf = vb2_vmalloc_dmabuf_ops_map,
	342	.unmap_dma_buf = vb2_vmalloc_dmabuf_ops_unmap,
	343	.kmap = vb2_vmalloc_dmabuf_ops_kmap,
	344	.kmap_atomic = vb2_vmalloc_dmabuf_ops_kmap,
	345	.vmap = vb2_vmalloc_dmabuf_ops_vmap,
	346	.mmap = vb2_vmalloc_dmabuf_ops_mmap,
	347	.release = vb2_vmalloc_dmabuf_ops_release,
	348	};
	349
	350	static struct dma_buf vb2_vmalloc_get_dmabuf(void buf_priv, unsigned long flags)
	351	{
	352	struct vb2_vmalloc_buf *buf = buf_priv;
	353	struct dma_buf *dbuf;
d8fbe341 SS	354	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
	355
	356	exp_info.ops = &vb2_vmalloc_dmabuf_ops;
	357	exp_info.size = buf->size;
	358	exp_info.flags = flags;
	359	exp_info.priv = buf;
46506350 HV	360
	361	if (WARN_ON(!buf->vaddr))
	362	return NULL;
	363
d8fbe341	364	dbuf = dma_buf_export(&exp_info);
46506350 HV	365	if (IS_ERR(dbuf))
	366	return NULL;
	367
	368	/* dmabuf keeps reference to vb2 buffer */
	369	atomic_inc(&buf->refcount);
	370
	371	return dbuf;
	372	}
99f3cd52 GU	373	#endif /* CONFIG_HAS_DMA */
99f3cd52 GU	374
46506350	375
89d2ee08 TS	376	/*********************************************/
	377	/* callbacks for DMABUF buffers */
	378	/*********************************************/
	379
	380	static int vb2_vmalloc_map_dmabuf(void *mem_priv)
	381	{
	382	struct vb2_vmalloc_buf *buf = mem_priv;
	383
	384	buf->vaddr = dma_buf_vmap(buf->dbuf);
	385
	386	return buf->vaddr ? 0 : -EFAULT;
	387	}
	388
	389	static void vb2_vmalloc_unmap_dmabuf(void *mem_priv)
	390	{
	391	struct vb2_vmalloc_buf *buf = mem_priv;
	392
	393	dma_buf_vunmap(buf->dbuf, buf->vaddr);
	394	buf->vaddr = NULL;
	395	}
	396
	397	static void vb2_vmalloc_detach_dmabuf(void *mem_priv)
	398	{
	399	struct vb2_vmalloc_buf *buf = mem_priv;
	400
	401	if (buf->vaddr)
	402	dma_buf_vunmap(buf->dbuf, buf->vaddr);
	403
	404	kfree(buf);
	405	}
	406
36c0f8b3	407	static void vb2_vmalloc_attach_dmabuf(struct device dev, struct dma_buf *dbuf,
cd474037	408	unsigned long size, enum dma_data_direction dma_dir)
89d2ee08 TS	409	{
	410	struct vb2_vmalloc_buf *buf;
	411
	412	if (dbuf->size < size)
	413	return ERR_PTR(-EFAULT);
	414
	415	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
	416	if (!buf)
	417	return ERR_PTR(-ENOMEM);
	418
	419	buf->dbuf = dbuf;
cd474037	420	buf->dma_dir = dma_dir;
89d2ee08 TS	421	buf->size = size;
	422
	423	return buf;
	424	}
	425
	426
3c18ff06 PO	427	const struct vb2_mem_ops vb2_vmalloc_memops = {
	428	.alloc = vb2_vmalloc_alloc,
	429	.put = vb2_vmalloc_put,
4419b8ac AP	430	.get_userptr = vb2_vmalloc_get_userptr,
4419b8ac AP	431	.put_userptr = vb2_vmalloc_put_userptr,
99f3cd52	432	#ifdef CONFIG_HAS_DMA
46506350	433	.get_dmabuf = vb2_vmalloc_get_dmabuf,
99f3cd52	434	#endif
89d2ee08 TS	435	.map_dmabuf = vb2_vmalloc_map_dmabuf,
	436	.unmap_dmabuf = vb2_vmalloc_unmap_dmabuf,
	437	.attach_dmabuf = vb2_vmalloc_attach_dmabuf,
	438	.detach_dmabuf = vb2_vmalloc_detach_dmabuf,
3c18ff06 PO	439	.vaddr = vb2_vmalloc_vaddr,
	440	.mmap = vb2_vmalloc_mmap,
	441	.num_users = vb2_vmalloc_num_users,
	442	};
	443	EXPORT_SYMBOL_GPL(vb2_vmalloc_memops);
	444
	445	MODULE_DESCRIPTION("vmalloc memory handling routines for videobuf2");
95072084	446	MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
3c18ff06	447	MODULE_LICENSE("GPL");