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