[mirror_ubuntu-disco-kernel.git] / drivers / media / common / videobuf2 / 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/refcount.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;
	refcount_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);
	}

	refcount_set(&buf->refcount, 1);
	return buf;
}

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

	if (refcount_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 ||
					       dma_dir == DMA_BIDIRECTIONAL);
	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(__pfn_to_phys(nums[0]), size + offset);
	} 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 ||
		    buf->dma_dir == DMA_BIDIRECTIONAL)
			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 refcount_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 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 const 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,
	.map = 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 */
	refcount_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>
6c4bb65d	16	#include <linux/refcount.h>
4419b8ac	17	#include <linux/sched.h>
3c18ff06 PO	18	#include <linux/slab.h>
	19	#include <linux/vmalloc.h>
	20
c139990e	21	#include <media/videobuf2-v4l2.h>
ddb9fa25	22	#include <media/videobuf2-vmalloc.h>
3c18ff06 PO	23	#include <media/videobuf2-memops.h>
	24
	25	struct vb2_vmalloc_buf {
	26	void *vaddr;
5a9e4dec	27	struct frame_vector *vec;
cd474037	28	enum dma_data_direction dma_dir;
3c18ff06	29	unsigned long size;
6c4bb65d	30	refcount_t refcount;
3c18ff06	31	struct vb2_vmarea_handler handler;
89d2ee08	32	struct dma_buf *dbuf;
3c18ff06 PO	33	};
	34
	35	static void vb2_vmalloc_put(void *buf_priv);
	36
00085f1e	37	static void vb2_vmalloc_alloc(struct device dev, unsigned long attrs,
d16e832d HV	38	unsigned long size, enum dma_data_direction dma_dir,
d16e832d HV	39	gfp_t gfp_flags)
3c18ff06 PO	40	{
	41	struct vb2_vmalloc_buf *buf;
	42
b6ba2057	43	buf = kzalloc(sizeof(*buf), GFP_KERNEL \| gfp_flags);
3c18ff06	44	if (!buf)
0ff657b0	45	return ERR_PTR(-ENOMEM);
3c18ff06 PO	46
	47	buf->size = size;
	48	buf->vaddr = vmalloc_user(buf->size);
d935c57e	49	buf->dma_dir = dma_dir;
3c18ff06 PO	50	buf->handler.refcount = &buf->refcount;
	51	buf->handler.put = vb2_vmalloc_put;
	52	buf->handler.arg = buf;
	53
	54	if (!buf->vaddr) {
4419b8ac	55	pr_debug("vmalloc of size %ld failed\n", buf->size);
3c18ff06	56	kfree(buf);
0ff657b0	57	return ERR_PTR(-ENOMEM);
3c18ff06 PO	58	}
3c18ff06 PO	59
6c4bb65d	60	refcount_set(&buf->refcount, 1);
3c18ff06 PO	61	return buf;
	62	}
	63
	64	static void vb2_vmalloc_put(void *buf_priv)
	65	{
	66	struct vb2_vmalloc_buf *buf = buf_priv;
	67
6c4bb65d	68	if (refcount_dec_and_test(&buf->refcount)) {
3c18ff06 PO	69	vfree(buf->vaddr);
	70	kfree(buf);
	71	}
	72	}
	73
36c0f8b3	74	static void vb2_vmalloc_get_userptr(struct device dev, unsigned long vaddr,
cd474037 HV	75	unsigned long size,
cd474037 HV	76	enum dma_data_direction dma_dir)
4419b8ac AP	77	{
4419b8ac AP	78	struct vb2_vmalloc_buf *buf;
5a9e4dec JK	79	struct frame_vector *vec;
5a9e4dec JK	80	int n_pages, offset, i;
0ff657b0	81	int ret = -ENOMEM;
4419b8ac AP	82
	83	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
	84	if (!buf)
0ff657b0	85	return ERR_PTR(-ENOMEM);
4419b8ac	86
cd474037	87	buf->dma_dir = dma_dir;
4419b8ac AP	88	offset = vaddr & ~PAGE_MASK;
4419b8ac AP	89	buf->size = size;
5b6f9abe SV	90	vec = vb2_create_framevec(vaddr, size, dma_dir == DMA_FROM_DEVICE \|\|
5b6f9abe SV	91	dma_dir == DMA_BIDIRECTIONAL);
0ff657b0 HV	92	if (IS_ERR(vec)) {
0ff657b0 HV	93	ret = PTR_ERR(vec);
5a9e4dec	94	goto fail_pfnvec_create;
0ff657b0	95	}
5a9e4dec JK	96	buf->vec = vec;
	97	n_pages = frame_vector_count(vec);
	98	if (frame_vector_to_pages(vec) < 0) {
	99	unsigned long *nums = frame_vector_pfns(vec);
	100
	101	/*
	102	* We cannot get page pointers for these pfns. Check memory is
	103	* physically contiguous and use direct mapping.
	104	*/
	105	for (i = 1; i < n_pages; i++)
	106	if (nums[i-1] + 1 != nums[i])
	107	goto fail_map;
	108	buf->vaddr = (__force void *)
d13a0139	109	ioremap_nocache(__pfn_to_phys(nums[0]), size + offset);
570d2a48	110	} else {
5a9e4dec	111	buf->vaddr = vm_map_ram(frame_vector_pages(vec), n_pages, -1,
570d2a48	112	PAGE_KERNEL);
570d2a48	113	}
4419b8ac	114
5a9e4dec JK	115	if (!buf->vaddr)
5a9e4dec JK	116	goto fail_map;
4419b8ac AP	117	buf->vaddr += offset;
	118	return buf;
	119
5a9e4dec JK	120	fail_map:
	121	vb2_destroy_framevec(vec);
	122	fail_pfnvec_create:
4419b8ac AP	123	kfree(buf);
4419b8ac AP	124
0ff657b0	125	return ERR_PTR(ret);
4419b8ac AP	126	}
	127
	128	static void vb2_vmalloc_put_userptr(void *buf_priv)
3c18ff06 PO	129	{
3c18ff06 PO	130	struct vb2_vmalloc_buf *buf = buf_priv;
4419b8ac AP	131	unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK;
4419b8ac AP	132	unsigned int i;
5a9e4dec JK	133	struct page **pages;
5a9e4dec JK	134	unsigned int n_pages;
4419b8ac	135
5a9e4dec JK	136	if (!buf->vec->is_pfns) {
	137	n_pages = frame_vector_count(buf->vec);
	138	pages = frame_vector_pages(buf->vec);
570d2a48	139	if (vaddr)
5a9e4dec	140	vm_unmap_ram((void *)vaddr, n_pages);
5b6f9abe SV	141	if (buf->dma_dir == DMA_FROM_DEVICE \|\|
5b6f9abe SV	142	buf->dma_dir == DMA_BIDIRECTIONAL)
5a9e4dec JK	143	for (i = 0; i < n_pages; i++)
5a9e4dec JK	144	set_page_dirty_lock(pages[i]);
570d2a48	145	} else {
7c424dd1	146	iounmap((__force void __iomem *)buf->vaddr);
4419b8ac	147	}
5a9e4dec	148	vb2_destroy_framevec(buf->vec);
4419b8ac AP	149	kfree(buf);
4419b8ac AP	150	}
3c18ff06	151
4419b8ac AP	152	static void vb2_vmalloc_vaddr(void buf_priv)
	153	{
	154	struct vb2_vmalloc_buf *buf = buf_priv;
3c18ff06 PO	155
3c18ff06 PO	156	if (!buf->vaddr) {
8720427c	157	pr_err("Address of an unallocated plane requested or cannot map user pointer\n");
3c18ff06 PO	158	return NULL;
	159	}
	160
	161	return buf->vaddr;
	162	}
	163
	164	static unsigned int vb2_vmalloc_num_users(void *buf_priv)
	165	{
	166	struct vb2_vmalloc_buf *buf = buf_priv;
6c4bb65d	167	return refcount_read(&buf->refcount);
3c18ff06 PO	168	}
	169
	170	static int vb2_vmalloc_mmap(void buf_priv, struct vm_area_struct vma)
	171	{
	172	struct vb2_vmalloc_buf *buf = buf_priv;
	173	int ret;
	174
	175	if (!buf) {
4419b8ac	176	pr_err("No memory to map\n");
3c18ff06 PO	177	return -EINVAL;
	178	}
	179
	180	ret = remap_vmalloc_range(vma, buf->vaddr, 0);
	181	if (ret) {
4419b8ac	182	pr_err("Remapping vmalloc memory, error: %d\n", ret);
3c18ff06 PO	183	return ret;
	184	}
	185
	186	/*
	187	* Make sure that vm_areas for 2 buffers won't be merged together
	188	*/
	189	vma->vm_flags \|= VM_DONTEXPAND;
	190
	191	/*
	192	* Use common vm_area operations to track buffer refcount.
	193	*/
	194	vma->vm_private_data = &buf->handler;
	195	vma->vm_ops = &vb2_common_vm_ops;
	196
	197	vma->vm_ops->open(vma);
	198
	199	return 0;
	200	}
	201
99f3cd52	202	#ifdef CONFIG_HAS_DMA
46506350 HV	203	/*********************************************/
	204	/* DMABUF ops for exporters */
	205	/*********************************************/
	206
	207	struct vb2_vmalloc_attachment {
	208	struct sg_table sgt;
	209	enum dma_data_direction dma_dir;
	210	};
	211
a19741e5	212	static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf *dbuf,
46506350 HV	213	struct dma_buf_attachment *dbuf_attach)
	214	{
	215	struct vb2_vmalloc_attachment *attach;
	216	struct vb2_vmalloc_buf *buf = dbuf->priv;
	217	int num_pages = PAGE_ALIGN(buf->size) / PAGE_SIZE;
	218	struct sg_table *sgt;
	219	struct scatterlist *sg;
	220	void *vaddr = buf->vaddr;
	221	int ret;
	222	int i;
	223
	224	attach = kzalloc(sizeof(*attach), GFP_KERNEL);
	225	if (!attach)
	226	return -ENOMEM;
	227
	228	sgt = &attach->sgt;
	229	ret = sg_alloc_table(sgt, num_pages, GFP_KERNEL);
	230	if (ret) {
	231	kfree(attach);
	232	return ret;
	233	}
	234	for_each_sg(sgt->sgl, sg, sgt->nents, i) {
	235	struct page *page = vmalloc_to_page(vaddr);
	236
	237	if (!page) {
	238	sg_free_table(sgt);
	239	kfree(attach);
	240	return -ENOMEM;
	241	}
	242	sg_set_page(sg, page, PAGE_SIZE, 0);
	243	vaddr += PAGE_SIZE;
	244	}
	245
	246	attach->dma_dir = DMA_NONE;
	247	dbuf_attach->priv = attach;
	248	return 0;
	249	}
	250
	251	static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf *dbuf,
	252	struct dma_buf_attachment *db_attach)
	253	{
	254	struct vb2_vmalloc_attachment *attach = db_attach->priv;
	255	struct sg_table *sgt;
	256
	257	if (!attach)
	258	return;
	259
	260	sgt = &attach->sgt;
	261
	262	/* release the scatterlist cache */
	263	if (attach->dma_dir != DMA_NONE)
	264	dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
	265	attach->dma_dir);
	266	sg_free_table(sgt);
	267	kfree(attach);
	268	db_attach->priv = NULL;
	269	}
	270
	271	static struct sg_table *vb2_vmalloc_dmabuf_ops_map(
	272	struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir)
	273	{
	274	struct vb2_vmalloc_attachment *attach = db_attach->priv;
	275	/* stealing dmabuf mutex to serialize map/unmap operations */
	276	struct mutex *lock = &db_attach->dmabuf->lock;
277	struct sg_table *sgt;
46506350 HV	278
	279	mutex_lock(lock);
	280
	281	sgt = &attach->sgt;
	282	/* return previously mapped sg table */
	283	if (attach->dma_dir == dma_dir) {
	284	mutex_unlock(lock);
	285	return sgt;
	286	}
	287
	288	/* release any previous cache */
	289	if (attach->dma_dir != DMA_NONE) {
	290	dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
	291	attach->dma_dir);
	292	attach->dma_dir = DMA_NONE;
	293	}
	294
	295	/* mapping to the client with new direction */
ba81c6ed RRD	296	sgt->nents = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
	297	dma_dir);
	298	if (!sgt->nents) {
46506350 HV	299	pr_err("failed to map scatterlist\n");
	300	mutex_unlock(lock);
	301	return ERR_PTR(-EIO);
	302	}
	303
	304	attach->dma_dir = dma_dir;
	305
	306	mutex_unlock(lock);
	307
	308	return sgt;
	309	}
	310
	311	static void vb2_vmalloc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach,
	312	struct sg_table *sgt, enum dma_data_direction dma_dir)
	313	{
	314	/* nothing to be done here */
	315	}
	316
	317	static void vb2_vmalloc_dmabuf_ops_release(struct dma_buf *dbuf)
	318	{
	319	/* drop reference obtained in vb2_vmalloc_get_dmabuf */
	320	vb2_vmalloc_put(dbuf->priv);
	321	}
	322
	323	static void vb2_vmalloc_dmabuf_ops_kmap(struct dma_buf dbuf, unsigned long pgnum)
	324	{
	325	struct vb2_vmalloc_buf *buf = dbuf->priv;
	326
	327	return buf->vaddr + pgnum * PAGE_SIZE;
	328	}
	329
	330	static void vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf dbuf)
	331	{
	332	struct vb2_vmalloc_buf *buf = dbuf->priv;
	333
	334	return buf->vaddr;
	335	}
	336
	337	static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf,
	338	struct vm_area_struct *vma)
	339	{
	340	return vb2_vmalloc_mmap(dbuf->priv, vma);
	341	}
	342
59310b7a	343	static const struct dma_buf_ops vb2_vmalloc_dmabuf_ops = {
46506350 HV	344	.attach = vb2_vmalloc_dmabuf_ops_attach,
	345	.detach = vb2_vmalloc_dmabuf_ops_detach,
	346	.map_dma_buf = vb2_vmalloc_dmabuf_ops_map,
	347	.unmap_dma_buf = vb2_vmalloc_dmabuf_ops_unmap,
f9b67f00	348	.map = vb2_vmalloc_dmabuf_ops_kmap,
46506350 HV	349	.vmap = vb2_vmalloc_dmabuf_ops_vmap,
	350	.mmap = vb2_vmalloc_dmabuf_ops_mmap,
	351	.release = vb2_vmalloc_dmabuf_ops_release,
	352	};
	353
	354	static struct dma_buf vb2_vmalloc_get_dmabuf(void buf_priv, unsigned long flags)
	355	{
	356	struct vb2_vmalloc_buf *buf = buf_priv;
	357	struct dma_buf *dbuf;
d8fbe341 SS	358	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
	359
	360	exp_info.ops = &vb2_vmalloc_dmabuf_ops;
	361	exp_info.size = buf->size;
	362	exp_info.flags = flags;
	363	exp_info.priv = buf;
46506350 HV	364
	365	if (WARN_ON(!buf->vaddr))
	366	return NULL;
	367
d8fbe341	368	dbuf = dma_buf_export(&exp_info);
46506350 HV	369	if (IS_ERR(dbuf))
	370	return NULL;
	371
	372	/* dmabuf keeps reference to vb2 buffer */
6c4bb65d	373	refcount_inc(&buf->refcount);
46506350 HV	374
	375	return dbuf;
	376	}
99f3cd52 GU	377	#endif /* CONFIG_HAS_DMA */
99f3cd52 GU	378
46506350	379
89d2ee08 TS	380	/*********************************************/
	381	/* callbacks for DMABUF buffers */
	382	/*********************************************/
	383
	384	static int vb2_vmalloc_map_dmabuf(void *mem_priv)
	385	{
	386	struct vb2_vmalloc_buf *buf = mem_priv;
	387
	388	buf->vaddr = dma_buf_vmap(buf->dbuf);
	389
	390	return buf->vaddr ? 0 : -EFAULT;
	391	}
	392
	393	static void vb2_vmalloc_unmap_dmabuf(void *mem_priv)
	394	{
	395	struct vb2_vmalloc_buf *buf = mem_priv;
	396
	397	dma_buf_vunmap(buf->dbuf, buf->vaddr);
	398	buf->vaddr = NULL;
	399	}
	400
	401	static void vb2_vmalloc_detach_dmabuf(void *mem_priv)
	402	{
	403	struct vb2_vmalloc_buf *buf = mem_priv;
	404
	405	if (buf->vaddr)
	406	dma_buf_vunmap(buf->dbuf, buf->vaddr);
	407
	408	kfree(buf);
	409	}
	410
36c0f8b3	411	static void vb2_vmalloc_attach_dmabuf(struct device dev, struct dma_buf *dbuf,
cd474037	412	unsigned long size, enum dma_data_direction dma_dir)
89d2ee08 TS	413	{
	414	struct vb2_vmalloc_buf *buf;
	415
	416	if (dbuf->size < size)
	417	return ERR_PTR(-EFAULT);
	418
	419	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
	420	if (!buf)
	421	return ERR_PTR(-ENOMEM);
	422
	423	buf->dbuf = dbuf;
cd474037	424	buf->dma_dir = dma_dir;
89d2ee08 TS	425	buf->size = size;
	426
	427	return buf;
	428	}
	429
	430
3c18ff06 PO	431	const struct vb2_mem_ops vb2_vmalloc_memops = {
	432	.alloc = vb2_vmalloc_alloc,
	433	.put = vb2_vmalloc_put,
4419b8ac AP	434	.get_userptr = vb2_vmalloc_get_userptr,
4419b8ac AP	435	.put_userptr = vb2_vmalloc_put_userptr,
99f3cd52	436	#ifdef CONFIG_HAS_DMA
46506350	437	.get_dmabuf = vb2_vmalloc_get_dmabuf,
99f3cd52	438	#endif
89d2ee08 TS	439	.map_dmabuf = vb2_vmalloc_map_dmabuf,
	440	.unmap_dmabuf = vb2_vmalloc_unmap_dmabuf,
	441	.attach_dmabuf = vb2_vmalloc_attach_dmabuf,
	442	.detach_dmabuf = vb2_vmalloc_detach_dmabuf,
3c18ff06 PO	443	.vaddr = vb2_vmalloc_vaddr,
	444	.mmap = vb2_vmalloc_mmap,
	445	.num_users = vb2_vmalloc_num_users,
	446	};
	447	EXPORT_SYMBOL_GPL(vb2_vmalloc_memops);
	448
	449	MODULE_DESCRIPTION("vmalloc memory handling routines for videobuf2");
95072084	450	MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
3c18ff06	451	MODULE_LICENSE("GPL");