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

struct vb2_vmalloc_buf {
	void				*vaddr;
	struct page			**pages;
	struct vm_area_struct		*vma;
	enum dma_data_direction		dma_dir;
	unsigned long			size;
	unsigned int			n_pages;
	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, 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->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;
	unsigned long first, last;
	int n_pages, offset;
	struct vm_area_struct *vma;
	dma_addr_t physp;

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

	buf->dma_dir = dma_dir;
	offset = vaddr & ~PAGE_MASK;
	buf->size = size;


	vma = find_vma(current->mm, vaddr);
	if (vma && (vma->vm_flags & VM_PFNMAP) && (vma->vm_pgoff)) {
		if (vb2_get_contig_userptr(vaddr, size, &vma, &physp))
			goto fail_pages_array_alloc;
		buf->vma = vma;
		buf->vaddr = ioremap_nocache(physp, size);
		if (!buf->vaddr)
			goto fail_pages_array_alloc;
	} else {
		first = vaddr >> PAGE_SHIFT;
		last  = (vaddr + size - 1) >> PAGE_SHIFT;
		buf->n_pages = last - first + 1;
		buf->pages = kzalloc(buf->n_pages * sizeof(struct page *),
				     GFP_KERNEL);
		if (!buf->pages)
			goto fail_pages_array_alloc;

		/* current->mm->mmap_sem is taken by videobuf2 core */
		n_pages = get_user_pages(current, current->mm,
					 vaddr & PAGE_MASK, buf->n_pages,
					 dma_dir == DMA_FROM_DEVICE,
					 1, /* force */
					 buf->pages, NULL);
		if (n_pages != buf->n_pages)
			goto fail_get_user_pages;

		buf->vaddr = vm_map_ram(buf->pages, buf->n_pages, -1,
					PAGE_KERNEL);
		if (!buf->vaddr)
			goto fail_get_user_pages;
	}

	buf->vaddr += offset;
	return buf;

fail_get_user_pages:
	pr_debug("get_user_pages requested/got: %d/%d]\n", n_pages,
		 buf->n_pages);
	while (--n_pages >= 0)
		put_page(buf->pages[n_pages]);
	kfree(buf->pages);

fail_pages_array_alloc:
	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;

	if (buf->pages) {
		if (vaddr)
			vm_unmap_ram((void *)vaddr, buf->n_pages);
		for (i = 0; i < buf->n_pages; ++i) {
			if (buf->dma_dir == DMA_FROM_DEVICE)
				set_page_dirty_lock(buf->pages[i]);
			put_page(buf->pages[i]);
		}
		kfree(buf->pages);
	} else {
		if (buf->vma)
			vb2_put_vma(buf->vma);
		iounmap(buf->vaddr);
	}
	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;
}

/*********************************************/
/*       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,
	.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
	20	#include <media/videobuf2-core.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;
4419b8ac	26	struct page **pages;
570d2a48	27	struct vm_area_struct *vma;
cd474037	28	enum dma_data_direction dma_dir;
3c18ff06	29	unsigned long size;
4419b8ac	30	unsigned int n_pages;
3c18ff06 PO	31	atomic_t refcount;
3c18ff06 PO	32	struct vb2_vmarea_handler handler;
89d2ee08	33	struct dma_buf *dbuf;
3c18ff06 PO	34	};
	35
	36	static void vb2_vmalloc_put(void *buf_priv);
	37
b6ba2057	38	static void vb2_vmalloc_alloc(void alloc_ctx, unsigned long size, 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);
	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	{
	76	struct vb2_vmalloc_buf *buf;
	77	unsigned long first, last;
	78	int n_pages, offset;
570d2a48 JM	79	struct vm_area_struct *vma;
570d2a48 JM	80	dma_addr_t physp;
4419b8ac AP	81
	82	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
	83	if (!buf)
	84	return NULL;
	85
cd474037	86	buf->dma_dir = dma_dir;
4419b8ac AP	87	offset = vaddr & ~PAGE_MASK;
	88	buf->size = size;
	89
4419b8ac	90
570d2a48 JM	91	vma = find_vma(current->mm, vaddr);
	92	if (vma && (vma->vm_flags & VM_PFNMAP) && (vma->vm_pgoff)) {
	93	if (vb2_get_contig_userptr(vaddr, size, &vma, &physp))
	94	goto fail_pages_array_alloc;
	95	buf->vma = vma;
	96	buf->vaddr = ioremap_nocache(physp, size);
	97	if (!buf->vaddr)
	98	goto fail_pages_array_alloc;
	99	} else {
	100	first = vaddr >> PAGE_SHIFT;
	101	last = (vaddr + size - 1) >> PAGE_SHIFT;
	102	buf->n_pages = last - first + 1;
	103	buf->pages = kzalloc(buf->n_pages * sizeof(struct page *),
	104	GFP_KERNEL);
	105	if (!buf->pages)
	106	goto fail_pages_array_alloc;
	107
	108	/* current->mm->mmap_sem is taken by videobuf2 core */
	109	n_pages = get_user_pages(current, current->mm,
	110	vaddr & PAGE_MASK, buf->n_pages,
cd474037 HV	111	dma_dir == DMA_FROM_DEVICE,
cd474037 HV	112	1, /* force */
570d2a48 JM	113	buf->pages, NULL);
	114	if (n_pages != buf->n_pages)
	115	goto fail_get_user_pages;
	116
	117	buf->vaddr = vm_map_ram(buf->pages, buf->n_pages, -1,
	118	PAGE_KERNEL);
	119	if (!buf->vaddr)
	120	goto fail_get_user_pages;
	121	}
4419b8ac AP	122
	123	buf->vaddr += offset;
	124	return buf;
	125
	126	fail_get_user_pages:
	127	pr_debug("get_user_pages requested/got: %d/%d]\n", n_pages,
	128	buf->n_pages);
	129	while (--n_pages >= 0)
	130	put_page(buf->pages[n_pages]);
	131	kfree(buf->pages);
	132
	133	fail_pages_array_alloc:
	134	kfree(buf);
	135
	136	return NULL;
	137	}
	138
	139	static void vb2_vmalloc_put_userptr(void *buf_priv)
3c18ff06 PO	140	{
3c18ff06 PO	141	struct vb2_vmalloc_buf *buf = buf_priv;
4419b8ac AP	142	unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK;
	143	unsigned int i;
	144
570d2a48 JM	145	if (buf->pages) {
	146	if (vaddr)
	147	vm_unmap_ram((void *)vaddr, buf->n_pages);
	148	for (i = 0; i < buf->n_pages; ++i) {
cd474037	149	if (buf->dma_dir == DMA_FROM_DEVICE)
570d2a48 JM	150	set_page_dirty_lock(buf->pages[i]);
	151	put_page(buf->pages[i]);
	152	}
	153	kfree(buf->pages);
	154	} else {
	155	if (buf->vma)
	156	vb2_put_vma(buf->vma);
	157	iounmap(buf->vaddr);
4419b8ac	158	}
4419b8ac AP	159	kfree(buf);
4419b8ac AP	160	}
3c18ff06	161
4419b8ac AP	162	static void vb2_vmalloc_vaddr(void buf_priv)
	163	{
	164	struct vb2_vmalloc_buf *buf = buf_priv;
3c18ff06 PO	165
3c18ff06 PO	166	if (!buf->vaddr) {
4419b8ac AP	167	pr_err("Address of an unallocated plane requested "
4419b8ac AP	168	"or cannot map user pointer\n");
3c18ff06 PO	169	return NULL;
	170	}
	171
	172	return buf->vaddr;
	173	}
	174
	175	static unsigned int vb2_vmalloc_num_users(void *buf_priv)
	176	{
	177	struct vb2_vmalloc_buf *buf = buf_priv;
	178	return atomic_read(&buf->refcount);
	179	}
	180
	181	static int vb2_vmalloc_mmap(void buf_priv, struct vm_area_struct vma)
	182	{
	183	struct vb2_vmalloc_buf *buf = buf_priv;
	184	int ret;
	185
	186	if (!buf) {
4419b8ac	187	pr_err("No memory to map\n");
3c18ff06 PO	188	return -EINVAL;
	189	}
	190
	191	ret = remap_vmalloc_range(vma, buf->vaddr, 0);
	192	if (ret) {
4419b8ac	193	pr_err("Remapping vmalloc memory, error: %d\n", ret);
3c18ff06 PO	194	return ret;
	195	}
	196
	197	/*
	198	* Make sure that vm_areas for 2 buffers won't be merged together
	199	*/
	200	vma->vm_flags \|= VM_DONTEXPAND;
	201
	202	/*
	203	* Use common vm_area operations to track buffer refcount.
	204	*/
	205	vma->vm_private_data = &buf->handler;
	206	vma->vm_ops = &vb2_common_vm_ops;
	207
	208	vma->vm_ops->open(vma);
	209
	210	return 0;
	211	}
	212
89d2ee08 TS	213	/*********************************************/
	214	/* callbacks for DMABUF buffers */
	215	/*********************************************/
	216
	217	static int vb2_vmalloc_map_dmabuf(void *mem_priv)
	218	{
	219	struct vb2_vmalloc_buf *buf = mem_priv;
	220
	221	buf->vaddr = dma_buf_vmap(buf->dbuf);
	222
	223	return buf->vaddr ? 0 : -EFAULT;
	224	}
	225
	226	static void vb2_vmalloc_unmap_dmabuf(void *mem_priv)
	227	{
	228	struct vb2_vmalloc_buf *buf = mem_priv;
	229
	230	dma_buf_vunmap(buf->dbuf, buf->vaddr);
	231	buf->vaddr = NULL;
	232	}
	233
	234	static void vb2_vmalloc_detach_dmabuf(void *mem_priv)
	235	{
	236	struct vb2_vmalloc_buf *buf = mem_priv;
	237
	238	if (buf->vaddr)
	239	dma_buf_vunmap(buf->dbuf, buf->vaddr);
	240
	241	kfree(buf);
	242	}
	243
	244	static void vb2_vmalloc_attach_dmabuf(void alloc_ctx, struct dma_buf *dbuf,
cd474037	245	unsigned long size, enum dma_data_direction dma_dir)
89d2ee08 TS	246	{
	247	struct vb2_vmalloc_buf *buf;
	248
	249	if (dbuf->size < size)
	250	return ERR_PTR(-EFAULT);
	251
	252	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
	253	if (!buf)
	254	return ERR_PTR(-ENOMEM);
	255
	256	buf->dbuf = dbuf;
cd474037	257	buf->dma_dir = dma_dir;
89d2ee08 TS	258	buf->size = size;
	259
	260	return buf;
	261	}
	262
	263
3c18ff06 PO	264	const struct vb2_mem_ops vb2_vmalloc_memops = {
	265	.alloc = vb2_vmalloc_alloc,
	266	.put = vb2_vmalloc_put,
4419b8ac AP	267	.get_userptr = vb2_vmalloc_get_userptr,
4419b8ac AP	268	.put_userptr = vb2_vmalloc_put_userptr,
89d2ee08 TS	269	.map_dmabuf = vb2_vmalloc_map_dmabuf,
	270	.unmap_dmabuf = vb2_vmalloc_unmap_dmabuf,
	271	.attach_dmabuf = vb2_vmalloc_attach_dmabuf,
	272	.detach_dmabuf = vb2_vmalloc_detach_dmabuf,
3c18ff06 PO	273	.vaddr = vb2_vmalloc_vaddr,
	274	.mmap = vb2_vmalloc_mmap,
	275	.num_users = vb2_vmalloc_num_users,
	276	};
	277	EXPORT_SYMBOL_GPL(vb2_vmalloc_memops);
	278
	279	MODULE_DESCRIPTION("vmalloc memory handling routines for videobuf2");
95072084	280	MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
3c18ff06	281	MODULE_LICENSE("GPL");