[deliverable/linux.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 ERR_PTR(-ENOMEM);

	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 ERR_PTR(-ENOMEM);
	}

	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;
	int ret = -ENOMEM;

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

	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)) {
		ret = PTR_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 ERR_PTR(ret);
}

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	43	if (!buf)
0ff657b0	44	return ERR_PTR(-ENOMEM);
3c18ff06 PO	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	55	kfree(buf);
0ff657b0	56	return ERR_PTR(-ENOMEM);
3c18ff06 PO	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;
0ff657b0	80	int ret = -ENOMEM;
4419b8ac AP	81
	82	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
	83	if (!buf)
0ff657b0	84	return ERR_PTR(-ENOMEM);
4419b8ac	85
cd474037	86	buf->dma_dir = dma_dir;
4419b8ac AP	87	offset = vaddr & ~PAGE_MASK;
4419b8ac AP	88	buf->size = size;
5a9e4dec	89	vec = vb2_create_framevec(vaddr, size, dma_dir == DMA_FROM_DEVICE);
0ff657b0 HV	90	if (IS_ERR(vec)) {
0ff657b0 HV	91	ret = PTR_ERR(vec);
5a9e4dec	92	goto fail_pfnvec_create;
0ff657b0	93	}
5a9e4dec JK	94	buf->vec = vec;
	95	n_pages = frame_vector_count(vec);
	96	if (frame_vector_to_pages(vec) < 0) {
	97	unsigned long *nums = frame_vector_pfns(vec);
	98
	99	/*
	100	* We cannot get page pointers for these pfns. Check memory is
	101	* physically contiguous and use direct mapping.
	102	*/
	103	for (i = 1; i < n_pages; i++)
	104	if (nums[i-1] + 1 != nums[i])
	105	goto fail_map;
	106	buf->vaddr = (__force void *)
	107	ioremap_nocache(nums[0] << PAGE_SHIFT, size);
570d2a48	108	} else {
5a9e4dec	109	buf->vaddr = vm_map_ram(frame_vector_pages(vec), n_pages, -1,
570d2a48	110	PAGE_KERNEL);
570d2a48	111	}
4419b8ac	112
5a9e4dec JK	113	if (!buf->vaddr)
5a9e4dec JK	114	goto fail_map;
4419b8ac AP	115	buf->vaddr += offset;
	116	return buf;
	117
5a9e4dec JK	118	fail_map:
	119	vb2_destroy_framevec(vec);
	120	fail_pfnvec_create:
4419b8ac AP	121	kfree(buf);
4419b8ac AP	122
0ff657b0	123	return ERR_PTR(ret);
4419b8ac AP	124	}
	125
	126	static void vb2_vmalloc_put_userptr(void *buf_priv)
3c18ff06 PO	127	{
3c18ff06 PO	128	struct vb2_vmalloc_buf *buf = buf_priv;
4419b8ac AP	129	unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK;
4419b8ac AP	130	unsigned int i;
5a9e4dec JK	131	struct page **pages;
5a9e4dec JK	132	unsigned int n_pages;
4419b8ac	133
5a9e4dec JK	134	if (!buf->vec->is_pfns) {
	135	n_pages = frame_vector_count(buf->vec);
	136	pages = frame_vector_pages(buf->vec);
570d2a48	137	if (vaddr)
5a9e4dec JK	138	vm_unmap_ram((void *)vaddr, n_pages);
	139	if (buf->dma_dir == DMA_FROM_DEVICE)
	140	for (i = 0; i < n_pages; i++)
	141	set_page_dirty_lock(pages[i]);
570d2a48	142	} else {
7c424dd1	143	iounmap((__force void __iomem *)buf->vaddr);
4419b8ac	144	}
5a9e4dec	145	vb2_destroy_framevec(buf->vec);
4419b8ac AP	146	kfree(buf);
4419b8ac AP	147	}
3c18ff06	148
4419b8ac AP	149	static void vb2_vmalloc_vaddr(void buf_priv)
	150	{
	151	struct vb2_vmalloc_buf *buf = buf_priv;
3c18ff06 PO	152
3c18ff06 PO	153	if (!buf->vaddr) {
4419b8ac AP	154	pr_err("Address of an unallocated plane requested "
4419b8ac AP	155	"or cannot map user pointer\n");
3c18ff06 PO	156	return NULL;
	157	}
	158
	159	return buf->vaddr;
	160	}
	161
	162	static unsigned int vb2_vmalloc_num_users(void *buf_priv)
	163	{
	164	struct vb2_vmalloc_buf *buf = buf_priv;
	165	return atomic_read(&buf->refcount);
	166	}
	167
	168	static int vb2_vmalloc_mmap(void buf_priv, struct vm_area_struct vma)
	169	{
	170	struct vb2_vmalloc_buf *buf = buf_priv;
	171	int ret;
	172
	173	if (!buf) {
4419b8ac	174	pr_err("No memory to map\n");
3c18ff06 PO	175	return -EINVAL;
	176	}
	177
	178	ret = remap_vmalloc_range(vma, buf->vaddr, 0);
	179	if (ret) {
4419b8ac	180	pr_err("Remapping vmalloc memory, error: %d\n", ret);
3c18ff06 PO	181	return ret;
	182	}
	183
	184	/*
	185	* Make sure that vm_areas for 2 buffers won't be merged together
	186	*/
	187	vma->vm_flags \|= VM_DONTEXPAND;
	188
	189	/*
	190	* Use common vm_area operations to track buffer refcount.
	191	*/
	192	vma->vm_private_data = &buf->handler;
	193	vma->vm_ops = &vb2_common_vm_ops;
	194
	195	vma->vm_ops->open(vma);
	196
	197	return 0;
	198	}
	199
99f3cd52	200	#ifdef CONFIG_HAS_DMA
46506350 HV	201	/*********************************************/
	202	/* DMABUF ops for exporters */
	203	/*********************************************/
	204
	205	struct vb2_vmalloc_attachment {
	206	struct sg_table sgt;
	207	enum dma_data_direction dma_dir;
	208	};
	209
	210	static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf dbuf, struct device dev,
	211	struct dma_buf_attachment *dbuf_attach)
	212	{
	213	struct vb2_vmalloc_attachment *attach;
	214	struct vb2_vmalloc_buf *buf = dbuf->priv;
	215	int num_pages = PAGE_ALIGN(buf->size) / PAGE_SIZE;
	216	struct sg_table *sgt;
	217	struct scatterlist *sg;
	218	void *vaddr = buf->vaddr;
	219	int ret;
	220	int i;
	221
	222	attach = kzalloc(sizeof(*attach), GFP_KERNEL);
	223	if (!attach)
	224	return -ENOMEM;
	225
	226	sgt = &attach->sgt;
	227	ret = sg_alloc_table(sgt, num_pages, GFP_KERNEL);
	228	if (ret) {
	229	kfree(attach);
	230	return ret;
	231	}
	232	for_each_sg(sgt->sgl, sg, sgt->nents, i) {
	233	struct page *page = vmalloc_to_page(vaddr);
	234
	235	if (!page) {
	236	sg_free_table(sgt);
	237	kfree(attach);
	238	return -ENOMEM;
	239	}
	240	sg_set_page(sg, page, PAGE_SIZE, 0);
	241	vaddr += PAGE_SIZE;
	242	}
	243
	244	attach->dma_dir = DMA_NONE;
	245	dbuf_attach->priv = attach;
	246	return 0;
	247	}
	248
	249	static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf *dbuf,
	250	struct dma_buf_attachment *db_attach)
	251	{
	252	struct vb2_vmalloc_attachment *attach = db_attach->priv;
	253	struct sg_table *sgt;
	254
	255	if (!attach)
	256	return;
	257
	258	sgt = &attach->sgt;
	259
	260	/* release the scatterlist cache */
	261	if (attach->dma_dir != DMA_NONE)
	262	dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
	263	attach->dma_dir);
	264	sg_free_table(sgt);
265	kfree(attach);
266	db_attach->priv = NULL;
267	}
268
269	static struct sg_table *vb2_vmalloc_dmabuf_ops_map(
270	struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir)
271	{
272	struct vb2_vmalloc_attachment *attach = db_attach->priv;
273	/* stealing dmabuf mutex to serialize map/unmap operations */
274	struct mutex *lock = &db_attach->dmabuf->lock;
275	struct sg_table *sgt;
46506350 HV	276
	277	mutex_lock(lock);
	278
	279	sgt = &attach->sgt;
	280	/* return previously mapped sg table */
	281	if (attach->dma_dir == dma_dir) {
	282	mutex_unlock(lock);
	283	return sgt;
	284	}
	285
	286	/* release any previous cache */
	287	if (attach->dma_dir != DMA_NONE) {
	288	dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
	289	attach->dma_dir);
	290	attach->dma_dir = DMA_NONE;
	291	}
	292
	293	/* mapping to the client with new direction */
ba81c6ed RR	294	sgt->nents = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
	295	dma_dir);
	296	if (!sgt->nents) {
46506350 HV	297	pr_err("failed to map scatterlist\n");
	298	mutex_unlock(lock);
	299	return ERR_PTR(-EIO);
	300	}
	301
	302	attach->dma_dir = dma_dir;
	303
	304	mutex_unlock(lock);
	305
	306	return sgt;
	307	}
	308
	309	static void vb2_vmalloc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach,
	310	struct sg_table *sgt, enum dma_data_direction dma_dir)
	311	{
	312	/* nothing to be done here */
	313	}
	314
	315	static void vb2_vmalloc_dmabuf_ops_release(struct dma_buf *dbuf)
	316	{
	317	/* drop reference obtained in vb2_vmalloc_get_dmabuf */
	318	vb2_vmalloc_put(dbuf->priv);
	319	}
	320
	321	static void vb2_vmalloc_dmabuf_ops_kmap(struct dma_buf dbuf, unsigned long pgnum)
	322	{
	323	struct vb2_vmalloc_buf *buf = dbuf->priv;
	324
	325	return buf->vaddr + pgnum * PAGE_SIZE;
	326	}
	327
	328	static void vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf dbuf)
	329	{
	330	struct vb2_vmalloc_buf *buf = dbuf->priv;
	331
	332	return buf->vaddr;
	333	}
	334
	335	static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf,
	336	struct vm_area_struct *vma)
	337	{
	338	return vb2_vmalloc_mmap(dbuf->priv, vma);
	339	}
	340
	341	static struct dma_buf_ops vb2_vmalloc_dmabuf_ops = {
	342	.attach = vb2_vmalloc_dmabuf_ops_attach,
	343	.detach = vb2_vmalloc_dmabuf_ops_detach,
	344	.map_dma_buf = vb2_vmalloc_dmabuf_ops_map,
	345	.unmap_dma_buf = vb2_vmalloc_dmabuf_ops_unmap,
	346	.kmap = vb2_vmalloc_dmabuf_ops_kmap,
	347	.kmap_atomic = vb2_vmalloc_dmabuf_ops_kmap,
	348	.vmap = vb2_vmalloc_dmabuf_ops_vmap,
	349	.mmap = vb2_vmalloc_dmabuf_ops_mmap,
	350	.release = vb2_vmalloc_dmabuf_ops_release,
	351	};
	352
	353	static struct dma_buf vb2_vmalloc_get_dmabuf(void buf_priv, unsigned long flags)
	354	{
	355	struct vb2_vmalloc_buf *buf = buf_priv;
	356	struct dma_buf *dbuf;
d8fbe341 SS	357	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
	358
	359	exp_info.ops = &vb2_vmalloc_dmabuf_ops;
	360	exp_info.size = buf->size;
	361	exp_info.flags = flags;
	362	exp_info.priv = buf;
46506350 HV	363
	364	if (WARN_ON(!buf->vaddr))
	365	return NULL;
	366
d8fbe341	367	dbuf = dma_buf_export(&exp_info);
46506350 HV	368	if (IS_ERR(dbuf))
	369	return NULL;
	370
	371	/* dmabuf keeps reference to vb2 buffer */
	372	atomic_inc(&buf->refcount);
	373
	374	return dbuf;
	375	}
99f3cd52 GU	376	#endif /* CONFIG_HAS_DMA */
99f3cd52 GU	377
46506350	378
89d2ee08 TS	379	/*********************************************/
	380	/* callbacks for DMABUF buffers */
	381	/*********************************************/
	382
	383	static int vb2_vmalloc_map_dmabuf(void *mem_priv)
	384	{
	385	struct vb2_vmalloc_buf *buf = mem_priv;
	386
	387	buf->vaddr = dma_buf_vmap(buf->dbuf);
	388
	389	return buf->vaddr ? 0 : -EFAULT;
	390	}
	391
	392	static void vb2_vmalloc_unmap_dmabuf(void *mem_priv)
	393	{
	394	struct vb2_vmalloc_buf *buf = mem_priv;
	395
	396	dma_buf_vunmap(buf->dbuf, buf->vaddr);
	397	buf->vaddr = NULL;
	398	}
	399
	400	static void vb2_vmalloc_detach_dmabuf(void *mem_priv)
	401	{
	402	struct vb2_vmalloc_buf *buf = mem_priv;
	403
	404	if (buf->vaddr)
	405	dma_buf_vunmap(buf->dbuf, buf->vaddr);
	406
	407	kfree(buf);
	408	}
	409
36c0f8b3	410	static void vb2_vmalloc_attach_dmabuf(struct device dev, struct dma_buf *dbuf,
cd474037	411	unsigned long size, enum dma_data_direction dma_dir)
89d2ee08 TS	412	{
	413	struct vb2_vmalloc_buf *buf;
	414
	415	if (dbuf->size < size)
	416	return ERR_PTR(-EFAULT);
	417
	418	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
	419	if (!buf)
	420	return ERR_PTR(-ENOMEM);
	421
	422	buf->dbuf = dbuf;
cd474037	423	buf->dma_dir = dma_dir;
89d2ee08 TS	424	buf->size = size;
	425
	426	return buf;
	427	}
	428
	429
3c18ff06 PO	430	const struct vb2_mem_ops vb2_vmalloc_memops = {
	431	.alloc = vb2_vmalloc_alloc,
	432	.put = vb2_vmalloc_put,
4419b8ac AP	433	.get_userptr = vb2_vmalloc_get_userptr,
4419b8ac AP	434	.put_userptr = vb2_vmalloc_put_userptr,
99f3cd52	435	#ifdef CONFIG_HAS_DMA
46506350	436	.get_dmabuf = vb2_vmalloc_get_dmabuf,
99f3cd52	437	#endif
89d2ee08 TS	438	.map_dmabuf = vb2_vmalloc_map_dmabuf,
	439	.unmap_dmabuf = vb2_vmalloc_unmap_dmabuf,
	440	.attach_dmabuf = vb2_vmalloc_attach_dmabuf,
	441	.detach_dmabuf = vb2_vmalloc_detach_dmabuf,
3c18ff06 PO	442	.vaddr = vb2_vmalloc_vaddr,
	443	.mmap = vb2_vmalloc_mmap,
	444	.num_users = vb2_vmalloc_num_users,
	445	};
	446	EXPORT_SYMBOL_GPL(vb2_vmalloc_memops);
	447
	448	MODULE_DESCRIPTION("vmalloc memory handling routines for videobuf2");
95072084	449	MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
3c18ff06	450	MODULE_LICENSE("GPL");