drivers/media/common/dma-buf-heaps/amlogic_heap_codec_mm.c - manifest_repos/amlogic-driver - Git at Google

 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
 /*
  * Copyright (c) 2019 Amlogic, Inc. All rights reserved.
  */

 #include <linux/dma-buf.h>
 #include <linux/dma-mapping.h>
 #include <linux/dma-heap.h>
 #include <linux/err.h>
 #include <linux/highmem.h>
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/scatterlist.h>
 #include <linux/sched/signal.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>

 #include <linux/amlogic/media/codec_mm/codec_mm.h>
 #include <linux/amlogic/media/codec_mm/dmabuf_manage.h>
 #include <linux/amlogic/media/dmabuf_heaps/amlogic_dmabuf_heap.h>

 #define DMA_BUF_CODEC_MM "CODEC_MM_DMA_BUF"

 struct codec_mm_heap_buffer {
 	struct dma_heap *heap;
 	struct list_head attachments;
 	//lock for buffer access
 	struct mutex lock;
 	unsigned long len;
 	struct sg_table sg_table;
 	int vmap_cnt;
 	void *vaddr;
 	//struct deferred_freelist_item deferred_free;
 	bool uncached;
 	unsigned long heap_flags;
 	void *priv;
 };

 struct dma_heap_attachment {
 	struct device *dev;
 	struct sg_table *table;
 	struct list_head list;
 	bool mapped;
 	bool uncached;
 };

 static struct sg_table *dup_sg_table(struct sg_table *table)
 {
 	struct sg_table *new_table;
 	int ret, i;
 	struct scatterlist *sg, *new_sg;

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

 	ret = sg_alloc_table(new_table, table->orig_nents, GFP_KERNEL);
 	if (ret) {
 		kfree(new_table);
 		return ERR_PTR(-ENOMEM);
 	}

 	new_sg = new_table->sgl;
 	for_each_sgtable_sg(table, sg, i) {
 		sg_set_page(new_sg, sg_page(sg), sg->length, sg->offset);
 		new_sg = sg_next(new_sg);
 	}

 	return new_table;
 }

 static int codec_mm_heap_attach(struct dma_buf *dmabuf,
 			      struct dma_buf_attachment *attachment)
 {
 	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
 	struct dma_heap_attachment *a;
 	struct sg_table *table;

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

 	table = dup_sg_table(&buffer->sg_table);
 	if (IS_ERR(table)) {
 		kfree(a);
 		return -ENOMEM;
 	}

 	a->table = table;
 	a->dev = attachment->dev;
 	INIT_LIST_HEAD(&a->list);
 	a->mapped = false;
 	a->uncached = buffer->uncached;
 	attachment->priv = a;

 	mutex_lock(&buffer->lock);
 	list_add(&a->list, &buffer->attachments);
 	mutex_unlock(&buffer->lock);

 	return 0;
 }

 static void codec_mm_heap_detach(struct dma_buf *dmabuf,
 			       struct dma_buf_attachment *attachment)
 {
 	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
 	struct dma_heap_attachment *a = attachment->priv;

 	mutex_lock(&buffer->lock);
 	list_del(&a->list);
 	mutex_unlock(&buffer->lock);

 	sg_free_table(a->table);
 	kfree(a->table);
 	kfree(a);
 }

 static struct sg_table *codec_mm_heap_map_dma_buf
 					(struct dma_buf_attachment *attachment,
 					enum dma_data_direction direction)
 {
 	struct dma_heap_attachment *a = attachment->priv;
 	struct sg_table *table = a->table;
 	int attr = 0;
 	int ret;

 	if (a->uncached)
 		attr = DMA_ATTR_SKIP_CPU_SYNC;

 	ret = dma_map_sgtable(attachment->dev, table, direction, attr);
 	if (ret)
 		return ERR_PTR(ret);

 	a->mapped = true;
 	return table;
 }

 static void codec_mm_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,
 				      struct sg_table *table,
 				      enum dma_data_direction direction)
 {
 	struct dma_heap_attachment *a = attachment->priv;
 	int attr = 0;

 	if (a->uncached)
 		attr = DMA_ATTR_SKIP_CPU_SYNC;
 	a->mapped = false;
 	dma_unmap_sgtable(attachment->dev, table, direction, attr);
 }

 static int codec_mm_heap_dma_buf_begin_cpu_access
 						(struct dma_buf *dmabuf,
 					enum dma_data_direction direction)
 {
 	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
 	struct dma_heap_attachment *a;

 	mutex_lock(&buffer->lock);

 	if (buffer->vmap_cnt)
 		invalidate_kernel_vmap_range(buffer->vaddr, buffer->len);

 	if (!buffer->uncached) {
 		list_for_each_entry(a, &buffer->attachments, list) {
 			if (!a->mapped)
 				continue;
 			dma_sync_sgtable_for_cpu(a->dev, a->table, direction);
 		}
 	}
 	mutex_unlock(&buffer->lock);

 	return 0;
 }

 static int codec_mm_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
 					      enum dma_data_direction direction)
 {
 	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
 	struct dma_heap_attachment *a;

 	mutex_lock(&buffer->lock);

 	if (buffer->vmap_cnt)
 		flush_kernel_vmap_range(buffer->vaddr, buffer->len);

 	if (!buffer->uncached) {
 		list_for_each_entry(a, &buffer->attachments, list) {
 			if (!a->mapped)
 				continue;
 			dma_sync_sgtable_for_device(a->dev, a->table,
 								direction);
 		}
 	}
 	mutex_unlock(&buffer->lock);

 	return 0;
 }

 static int codec_mm_heap_mmap(struct dma_buf *dmabuf,
 						struct vm_area_struct *vma)
 {
 	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
 	struct sg_table *table = &buffer->sg_table;
 	unsigned long addr = vma->vm_start;
 	struct sg_page_iter piter;
 	int ret;

 	if (buffer->uncached)
 		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);

 	for_each_sgtable_page(table, &piter, vma->vm_pgoff) {
 		struct page *page = sg_page_iter_page(&piter);

 		ret = remap_pfn_range(vma, addr, page_to_pfn(page), PAGE_SIZE,
 				      vma->vm_page_prot);
 		if (ret)
 			return ret;
 		addr += PAGE_SIZE;
 		if (addr >= vma->vm_end)
 			return 0;
 	}
 	return 0;
 }

 static void *codec_mm_heap_do_vmap(struct codec_mm_heap_buffer *buffer)
 {
 	struct sg_table *table = &buffer->sg_table;
 	int npages = PAGE_ALIGN(buffer->len) / PAGE_SIZE;
 	struct page **pages = vmalloc(sizeof(struct page *) * npages);
 	struct page **tmp = pages;
 	struct sg_page_iter piter;
 	pgprot_t pgprot = PAGE_KERNEL;
 	void *vaddr;

 	if (!pages)
 		return ERR_PTR(-ENOMEM);

 	if (buffer->uncached)
 		pgprot = pgprot_writecombine(PAGE_KERNEL);

 	for_each_sgtable_page(table, &piter, 0) {
 		WARN_ON(tmp - pages >= npages);
 		*tmp++ = sg_page_iter_page(&piter);
 	}

 	vaddr = vmap(pages, npages, VM_MAP, pgprot);
 	vfree(pages);

 	if (!vaddr)
 		return ERR_PTR(-ENOMEM);

 	return vaddr;
 }

 static int codec_mm_heap_vmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
 	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
 	void *vaddr;
 	int ret = 0;

 	mutex_lock(&buffer->lock);
 	if (buffer->vmap_cnt) {
 		buffer->vmap_cnt++;
 		iosys_map_set_vaddr(map, buffer->vaddr);
 		goto out;
 	}

 	vaddr = codec_mm_heap_do_vmap(buffer);
 	if (IS_ERR(vaddr)) {
 		ret = PTR_ERR(vaddr);
 		goto out;
 	}

 	buffer->vaddr = vaddr;
 	buffer->vmap_cnt++;
 	iosys_map_set_vaddr(map, buffer->vaddr);
 out:
 	mutex_unlock(&buffer->lock);

 	return ret;
 }

 static void codec_mm_heap_vunmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
 	struct codec_mm_heap_buffer *buffer = dmabuf->priv;

 	mutex_lock(&buffer->lock);
 	if (!--buffer->vmap_cnt) {
 		vunmap(buffer->vaddr);
 		buffer->vaddr = NULL;
 	}
 	mutex_unlock(&buffer->lock);
 	iosys_map_clear(map);
 }

 static int codec_mm_heap_zero_buffer(struct codec_mm_heap_buffer *buffer)
 {
 	struct sg_table *sgt = &buffer->sg_table;
 	struct sg_page_iter piter;
 	struct page *p;
 	void *vaddr;
 	int ret = 0;

 	for_each_sgtable_page(sgt, &piter, 0) {
 		p = sg_page_iter_page(&piter);
 		vaddr = kmap_atomic(p);
 		memset(vaddr, 0, PAGE_SIZE);
 		kunmap_atomic(vaddr);
 	}

 	return ret;
 }

 static void codec_mm_heap_dma_buf_release(struct dma_buf *dmabuf)
 {
 	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
 	struct sg_table *table;
 	phys_addr_t paddr = 0;
 	unsigned long heap_flags = buffer->heap_flags;

 	table = &buffer->sg_table;
 	if (!(heap_flags & DMABUF_FLAG_EXTEND_PROTECTED))
 		codec_mm_heap_zero_buffer(buffer);

 	paddr = PFN_PHYS(page_to_pfn(sg_page(table->sgl)));
 	if (codec_mm_free_for_dma(DMA_BUF_CODEC_MM, paddr))
 		pr_err("codec_mm free error, please fix it");

 	sg_free_table(table);
 	kfree(buffer);
 }

 static const struct dma_buf_ops codec_mm_heap_buf_ops = {
 	.attach = codec_mm_heap_attach,
 	.detach = codec_mm_heap_detach,
 	.map_dma_buf = codec_mm_heap_map_dma_buf,
 	.unmap_dma_buf = codec_mm_heap_unmap_dma_buf,
 	.begin_cpu_access = codec_mm_heap_dma_buf_begin_cpu_access,
 	.end_cpu_access = codec_mm_heap_dma_buf_end_cpu_access,
 	.mmap = codec_mm_heap_mmap,
 	.vmap = codec_mm_heap_vmap,
 	.vunmap = codec_mm_heap_vunmap,
 	.release = codec_mm_heap_dma_buf_release,
 };

 bool dmabuf_is_codec_mm_heap_buf(struct dma_buf *dmabuf)
 {
 	return dmabuf->ops == &codec_mm_heap_buf_ops;
 }
 EXPORT_SYMBOL(dmabuf_is_codec_mm_heap_buf);

 static struct dma_buf *codec_mm_heap_do_allocate(struct dma_heap *heap,
 					       unsigned long len,
 					       unsigned long fd_flags,
 					       unsigned long heap_flags,
 					       bool uncached)
 {
 	struct codec_mm_heap_buffer *buffer;
 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
 	struct dma_buf *dmabuf;
 	struct sg_table *table;
 	unsigned long paddr = 0;
 	int ret = -ENOMEM;
 	int memflags = CODEC_MM_FLAGS_DMA;

 	if (heap_flags & DMABUF_FLAG_EXTEND_PROTECTED)
 		memflags = CODEC_MM_FLAGS_TVP;

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

 	INIT_LIST_HEAD(&buffer->attachments);
 	mutex_init(&buffer->lock);
 	buffer->heap = heap;
 	buffer->len = len;
 	buffer->uncached = uncached;
 	buffer->heap_flags = heap_flags;

 	table = &buffer->sg_table;
 	if (sg_alloc_table(table, 1, GFP_KERNEL))
 		goto free_buffer;

 	paddr = codec_mm_alloc_for_dma(DMA_BUF_CODEC_MM,
 					PAGE_ALIGN(len) / PAGE_SIZE,
 					0,
 					memflags);
 	if (!paddr)
 		goto free_tables;

 	sg_set_page(table->sgl, pfn_to_page(PFN_DOWN(paddr)), len, 0);
 	/* create the dmabuf */
 	exp_info.exp_name = dma_heap_get_name(heap);
 	exp_info.ops = &codec_mm_heap_buf_ops;
 	exp_info.size = buffer->len;
 	exp_info.flags = fd_flags;
 	exp_info.priv = buffer;
 	dmabuf = dma_buf_export(&exp_info);
 	if (IS_ERR(dmabuf)) {
 		ret = PTR_ERR(dmabuf);
 		goto free_tables;
 	}
 	/*
 	 * For uncached buffers, we need to initially flush cpu cache, since
 	 * the __GFP_ZERO on the allocation means the zeroing was done by the
 	 * cpu and thus it is likely cached. Map (and implicitly flush) and
 	 * unmap it now so we don't get corruption later on.
 	 */
 	if (buffer->uncached && (!(heap_flags & DMABUF_FLAG_EXTEND_PROTECTED))) {
 		dma_map_sgtable(dma_heap_get_dev(heap), table,
 						DMA_BIDIRECTIONAL, 0);
 		dma_unmap_sgtable(dma_heap_get_dev(heap), table,
 						DMA_BIDIRECTIONAL, 0);
 	}

 	return dmabuf;
 free_tables:
 	if (paddr)
 		codec_mm_free_for_dma(DMA_BUF_CODEC_MM, paddr);
 	sg_free_table(table);
 free_buffer:
 	kfree(buffer);
 	pr_err("Allocate dmabuf %lx %lx %lx failed", len, fd_flags, heap_flags);
 	return ERR_PTR(ret);
 }

 static struct dma_buf *codec_mm_heap_allocate
 						(struct dma_heap *heap,
 						unsigned long len,
 						u32 fd_flags,
 						u64 heap_flags)
 {
 	if (!strcmp(dma_heap_get_name(heap), CODECMM_SECURE_HEAP_NAME))
 		heap_flags |= DMABUF_FLAG_EXTEND_PROTECTED;
 	else if (!strcmp(dma_heap_get_name(heap), CODECMM_CACHED_HEAP_NAME))
 		heap_flags |= DMABUF_FLAG_EXTEND_CACHED;

 	return codec_mm_heap_do_allocate(heap, len, fd_flags, heap_flags,
 		!(heap_flags & DMABUF_FLAG_EXTEND_CACHED));
 }

 /* Dummy function to be used until we can call coerce_mask_and_coherent */
 static struct dma_buf *codec_mm_heap_not_initialized
 						(struct dma_heap *heap,
 						unsigned long len,
 						u32 fd_flags,
 						u64 heap_flags)
 {
 	return ERR_PTR(-EBUSY);
 }

 static struct dma_heap_ops codec_mm_heap_ops = {
 	.allocate = codec_mm_heap_not_initialized,
 };

 int __init amlogic_codec_mm_dma_buf_init(void)
 {
 	struct dma_heap_export_info exp_info;
 	struct dma_heap *codec_mm_heap;

 	exp_info.name = CODECMM_HEAP_NAME;
 	exp_info.ops = &codec_mm_heap_ops;
 	exp_info.priv = NULL;
 	codec_mm_heap = dma_heap_add(&exp_info);
 	if (IS_ERR(codec_mm_heap))
 		return PTR_ERR(codec_mm_heap);
 	dma_coerce_mask_and_coherent(dma_heap_get_dev(codec_mm_heap),
 		DMA_BIT_MASK(64));
 	mb(); /* make sure we only set allocate after dma_mask is set */

 	exp_info.name = CODECMM_SECURE_HEAP_NAME;
 	exp_info.ops = &codec_mm_heap_ops;
 	exp_info.priv = NULL;
 	codec_mm_heap = dma_heap_add(&exp_info);
 	if (IS_ERR(codec_mm_heap))
 		return PTR_ERR(codec_mm_heap);
 	dma_coerce_mask_and_coherent(dma_heap_get_dev(codec_mm_heap),
 		DMA_BIT_MASK(64));
 	mb(); /* make sure we only set allocate after dma_mask is set */

 	exp_info.name = CODECMM_CACHED_HEAP_NAME;
 	exp_info.ops = &codec_mm_heap_ops;
 	exp_info.priv = NULL;
 	codec_mm_heap = dma_heap_add(&exp_info);
 	if (IS_ERR(codec_mm_heap))
 		return PTR_ERR(codec_mm_heap);
 	dma_coerce_mask_and_coherent(dma_heap_get_dev(codec_mm_heap),
 		DMA_BIT_MASK(64));
 	mb(); /* make sure we only set allocate after dma_mask is set */

 	codec_mm_heap_ops.allocate = codec_mm_heap_allocate;

 	pr_info("codecmm dmaheap:enter %s\n", __func__);
 	return 0;
 }

 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
	/*
	* Copyright (c) 2019 Amlogic, Inc. All rights reserved.
	*/

	#include <linux/dma-buf.h>
	#include <linux/dma-mapping.h>
	#include <linux/dma-heap.h>
	#include <linux/err.h>
	#include <linux/highmem.h>
	#include <linux/mm.h>
	#include <linux/module.h>
	#include <linux/scatterlist.h>
	#include <linux/sched/signal.h>
	#include <linux/slab.h>
	#include <linux/vmalloc.h>

	#include <linux/amlogic/media/codec_mm/codec_mm.h>
	#include <linux/amlogic/media/codec_mm/dmabuf_manage.h>
	#include <linux/amlogic/media/dmabuf_heaps/amlogic_dmabuf_heap.h>

	#define DMA_BUF_CODEC_MM "CODEC_MM_DMA_BUF"

	struct codec_mm_heap_buffer {
	struct dma_heap *heap;
	struct list_head attachments;
	//lock for buffer access
	struct mutex lock;
	unsigned long len;
	struct sg_table sg_table;
	int vmap_cnt;
	void *vaddr;
	//struct deferred_freelist_item deferred_free;
	bool uncached;
	unsigned long heap_flags;
	void *priv;
	};

	struct dma_heap_attachment {
	struct device *dev;
	struct sg_table *table;
	struct list_head list;
	bool mapped;
	bool uncached;
	};

	static struct sg_table dup_sg_table(struct sg_table table)
	{
	struct sg_table *new_table;
	int ret, i;
	struct scatterlist sg, new_sg;

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

	ret = sg_alloc_table(new_table, table->orig_nents, GFP_KERNEL);
	if (ret) {
	kfree(new_table);
	return ERR_PTR(-ENOMEM);
	}

	new_sg = new_table->sgl;
	for_each_sgtable_sg(table, sg, i) {
	sg_set_page(new_sg, sg_page(sg), sg->length, sg->offset);
	new_sg = sg_next(new_sg);
	}

	return new_table;
	}

	static int codec_mm_heap_attach(struct dma_buf *dmabuf,
	struct dma_buf_attachment *attachment)
	{
	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
	struct dma_heap_attachment *a;
	struct sg_table *table;

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

	table = dup_sg_table(&buffer->sg_table);
	if (IS_ERR(table)) {
	kfree(a);
	return -ENOMEM;
	}

	a->table = table;
	a->dev = attachment->dev;
	INIT_LIST_HEAD(&a->list);
	a->mapped = false;
	a->uncached = buffer->uncached;
	attachment->priv = a;

	mutex_lock(&buffer->lock);
	list_add(&a->list, &buffer->attachments);
	mutex_unlock(&buffer->lock);

	return 0;
	}

	static void codec_mm_heap_detach(struct dma_buf *dmabuf,
	struct dma_buf_attachment *attachment)
	{
	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
	struct dma_heap_attachment *a = attachment->priv;

	mutex_lock(&buffer->lock);
	list_del(&a->list);
	mutex_unlock(&buffer->lock);

	sg_free_table(a->table);
	kfree(a->table);
	kfree(a);
	}

	static struct sg_table *codec_mm_heap_map_dma_buf
	(struct dma_buf_attachment *attachment,
	enum dma_data_direction direction)
	{
	struct dma_heap_attachment *a = attachment->priv;
	struct sg_table *table = a->table;
	int attr = 0;
	int ret;

	if (a->uncached)
	attr = DMA_ATTR_SKIP_CPU_SYNC;

	ret = dma_map_sgtable(attachment->dev, table, direction, attr);
	if (ret)
	return ERR_PTR(ret);

	a->mapped = true;
	return table;
	}

	static void codec_mm_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,
	struct sg_table *table,
	enum dma_data_direction direction)
	{
	struct dma_heap_attachment *a = attachment->priv;
	int attr = 0;

	if (a->uncached)
	attr = DMA_ATTR_SKIP_CPU_SYNC;
	a->mapped = false;
	dma_unmap_sgtable(attachment->dev, table, direction, attr);
	}

	static int codec_mm_heap_dma_buf_begin_cpu_access
	(struct dma_buf *dmabuf,
	enum dma_data_direction direction)
	{
	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
	struct dma_heap_attachment *a;

	mutex_lock(&buffer->lock);

	if (buffer->vmap_cnt)
	invalidate_kernel_vmap_range(buffer->vaddr, buffer->len);

	if (!buffer->uncached) {
	list_for_each_entry(a, &buffer->attachments, list) {
	if (!a->mapped)
	continue;
	dma_sync_sgtable_for_cpu(a->dev, a->table, direction);
	}
	}
	mutex_unlock(&buffer->lock);

	return 0;
	}

	static int codec_mm_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
	enum dma_data_direction direction)
	{
	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
	struct dma_heap_attachment *a;

	mutex_lock(&buffer->lock);

	if (buffer->vmap_cnt)
	flush_kernel_vmap_range(buffer->vaddr, buffer->len);

	if (!buffer->uncached) {
	list_for_each_entry(a, &buffer->attachments, list) {
	if (!a->mapped)
	continue;
	dma_sync_sgtable_for_device(a->dev, a->table,
	direction);
	}
	}
	mutex_unlock(&buffer->lock);

	return 0;
	}

	static int codec_mm_heap_mmap(struct dma_buf *dmabuf,
	struct vm_area_struct *vma)
	{
	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
	struct sg_table *table = &buffer->sg_table;
	unsigned long addr = vma->vm_start;
	struct sg_page_iter piter;
	int ret;

	if (buffer->uncached)
	vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);

	for_each_sgtable_page(table, &piter, vma->vm_pgoff) {
	struct page *page = sg_page_iter_page(&piter);

	ret = remap_pfn_range(vma, addr, page_to_pfn(page), PAGE_SIZE,
	vma->vm_page_prot);
	if (ret)
	return ret;
	addr += PAGE_SIZE;
	if (addr >= vma->vm_end)
	return 0;
	}
	return 0;
	}

	static void codec_mm_heap_do_vmap(struct codec_mm_heap_buffer buffer)
	{
	struct sg_table *table = &buffer->sg_table;
	int npages = PAGE_ALIGN(buffer->len) / PAGE_SIZE;
	struct page *pages = vmalloc(sizeof(struct page ) * npages);
	struct page **tmp = pages;
	struct sg_page_iter piter;
	pgprot_t pgprot = PAGE_KERNEL;
	void *vaddr;

	if (!pages)
	return ERR_PTR(-ENOMEM);

	if (buffer->uncached)
	pgprot = pgprot_writecombine(PAGE_KERNEL);

	for_each_sgtable_page(table, &piter, 0) {
	WARN_ON(tmp - pages >= npages);
	*tmp++ = sg_page_iter_page(&piter);
	}

	vaddr = vmap(pages, npages, VM_MAP, pgprot);
	vfree(pages);

	if (!vaddr)
	return ERR_PTR(-ENOMEM);

	return vaddr;
	}

	static int codec_mm_heap_vmap(struct dma_buf dmabuf, struct iosys_map map)
	{
	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
	void *vaddr;
	int ret = 0;

	mutex_lock(&buffer->lock);
	if (buffer->vmap_cnt) {
	buffer->vmap_cnt++;
	iosys_map_set_vaddr(map, buffer->vaddr);
	goto out;
	}

	vaddr = codec_mm_heap_do_vmap(buffer);
	if (IS_ERR(vaddr)) {
	ret = PTR_ERR(vaddr);
	goto out;
	}

	buffer->vaddr = vaddr;
	buffer->vmap_cnt++;
	iosys_map_set_vaddr(map, buffer->vaddr);
	out:
	mutex_unlock(&buffer->lock);

	return ret;
	}

	static void codec_mm_heap_vunmap(struct dma_buf dmabuf, struct iosys_map map)
	{
	struct codec_mm_heap_buffer *buffer = dmabuf->priv;

	mutex_lock(&buffer->lock);
	if (!--buffer->vmap_cnt) {
	vunmap(buffer->vaddr);
	buffer->vaddr = NULL;
	}
	mutex_unlock(&buffer->lock);
	iosys_map_clear(map);
	}

	static int codec_mm_heap_zero_buffer(struct codec_mm_heap_buffer *buffer)
	{
	struct sg_table *sgt = &buffer->sg_table;
	struct sg_page_iter piter;
	struct page *p;
	void *vaddr;
	int ret = 0;

	for_each_sgtable_page(sgt, &piter, 0) {
	p = sg_page_iter_page(&piter);
	vaddr = kmap_atomic(p);
	memset(vaddr, 0, PAGE_SIZE);
	kunmap_atomic(vaddr);
	}

	return ret;
	}

	static void codec_mm_heap_dma_buf_release(struct dma_buf *dmabuf)
	{
	struct codec_mm_heap_buffer *buffer = dmabuf->priv;
	struct sg_table *table;
	phys_addr_t paddr = 0;
	unsigned long heap_flags = buffer->heap_flags;

	table = &buffer->sg_table;
	if (!(heap_flags & DMABUF_FLAG_EXTEND_PROTECTED))
	codec_mm_heap_zero_buffer(buffer);

	paddr = PFN_PHYS(page_to_pfn(sg_page(table->sgl)));
	if (codec_mm_free_for_dma(DMA_BUF_CODEC_MM, paddr))
	pr_err("codec_mm free error, please fix it");

	sg_free_table(table);
	kfree(buffer);
	}

	static const struct dma_buf_ops codec_mm_heap_buf_ops = {
	.attach = codec_mm_heap_attach,
	.detach = codec_mm_heap_detach,
	.map_dma_buf = codec_mm_heap_map_dma_buf,
	.unmap_dma_buf = codec_mm_heap_unmap_dma_buf,
	.begin_cpu_access = codec_mm_heap_dma_buf_begin_cpu_access,
	.end_cpu_access = codec_mm_heap_dma_buf_end_cpu_access,
	.mmap = codec_mm_heap_mmap,
	.vmap = codec_mm_heap_vmap,
	.vunmap = codec_mm_heap_vunmap,
	.release = codec_mm_heap_dma_buf_release,
	};

	bool dmabuf_is_codec_mm_heap_buf(struct dma_buf *dmabuf)
	{
	return dmabuf->ops == &codec_mm_heap_buf_ops;
	}
	EXPORT_SYMBOL(dmabuf_is_codec_mm_heap_buf);

	static struct dma_buf codec_mm_heap_do_allocate(struct dma_heap heap,
	unsigned long len,
	unsigned long fd_flags,
	unsigned long heap_flags,
	bool uncached)
	{
	struct codec_mm_heap_buffer *buffer;
	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
	struct dma_buf *dmabuf;
	struct sg_table *table;
	unsigned long paddr = 0;
	int ret = -ENOMEM;
	int memflags = CODEC_MM_FLAGS_DMA;

	if (heap_flags & DMABUF_FLAG_EXTEND_PROTECTED)
	memflags = CODEC_MM_FLAGS_TVP;

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

	INIT_LIST_HEAD(&buffer->attachments);
	mutex_init(&buffer->lock);
	buffer->heap = heap;
	buffer->len = len;
	buffer->uncached = uncached;
	buffer->heap_flags = heap_flags;

	table = &buffer->sg_table;
	if (sg_alloc_table(table, 1, GFP_KERNEL))
	goto free_buffer;

	paddr = codec_mm_alloc_for_dma(DMA_BUF_CODEC_MM,
	PAGE_ALIGN(len) / PAGE_SIZE,
	0,
	memflags);
	if (!paddr)
	goto free_tables;

	sg_set_page(table->sgl, pfn_to_page(PFN_DOWN(paddr)), len, 0);
	/* create the dmabuf */
	exp_info.exp_name = dma_heap_get_name(heap);
	exp_info.ops = &codec_mm_heap_buf_ops;
	exp_info.size = buffer->len;
	exp_info.flags = fd_flags;
	exp_info.priv = buffer;
	dmabuf = dma_buf_export(&exp_info);
	if (IS_ERR(dmabuf)) {
	ret = PTR_ERR(dmabuf);
	goto free_tables;
	}
	/*
	* For uncached buffers, we need to initially flush cpu cache, since
	* the __GFP_ZERO on the allocation means the zeroing was done by the
	* cpu and thus it is likely cached. Map (and implicitly flush) and
	* unmap it now so we don't get corruption later on.
	*/
	if (buffer->uncached && (!(heap_flags & DMABUF_FLAG_EXTEND_PROTECTED))) {
	dma_map_sgtable(dma_heap_get_dev(heap), table,
	DMA_BIDIRECTIONAL, 0);
	dma_unmap_sgtable(dma_heap_get_dev(heap), table,
	DMA_BIDIRECTIONAL, 0);
	}

	return dmabuf;
	free_tables:
	if (paddr)
	codec_mm_free_for_dma(DMA_BUF_CODEC_MM, paddr);
	sg_free_table(table);
	free_buffer:
	kfree(buffer);
	pr_err("Allocate dmabuf %lx %lx %lx failed", len, fd_flags, heap_flags);
	return ERR_PTR(ret);
	}

	static struct dma_buf *codec_mm_heap_allocate
	(struct dma_heap *heap,
	unsigned long len,
	u32 fd_flags,
	u64 heap_flags)
	{
	if (!strcmp(dma_heap_get_name(heap), CODECMM_SECURE_HEAP_NAME))
	heap_flags \|= DMABUF_FLAG_EXTEND_PROTECTED;
	else if (!strcmp(dma_heap_get_name(heap), CODECMM_CACHED_HEAP_NAME))
	heap_flags \|= DMABUF_FLAG_EXTEND_CACHED;

	return codec_mm_heap_do_allocate(heap, len, fd_flags, heap_flags,
	!(heap_flags & DMABUF_FLAG_EXTEND_CACHED));
	}

	/* Dummy function to be used until we can call coerce_mask_and_coherent */
	static struct dma_buf *codec_mm_heap_not_initialized
	(struct dma_heap *heap,
	unsigned long len,
	u32 fd_flags,
	u64 heap_flags)
	{
	return ERR_PTR(-EBUSY);
	}

	static struct dma_heap_ops codec_mm_heap_ops = {
	.allocate = codec_mm_heap_not_initialized,
	};

	int __init amlogic_codec_mm_dma_buf_init(void)
	{
	struct dma_heap_export_info exp_info;
	struct dma_heap *codec_mm_heap;

	exp_info.name = CODECMM_HEAP_NAME;
	exp_info.ops = &codec_mm_heap_ops;
	exp_info.priv = NULL;
	codec_mm_heap = dma_heap_add(&exp_info);
	if (IS_ERR(codec_mm_heap))
	return PTR_ERR(codec_mm_heap);
	dma_coerce_mask_and_coherent(dma_heap_get_dev(codec_mm_heap),
	DMA_BIT_MASK(64));
	mb(); /* make sure we only set allocate after dma_mask is set */

	exp_info.name = CODECMM_SECURE_HEAP_NAME;
	exp_info.ops = &codec_mm_heap_ops;
	exp_info.priv = NULL;
	codec_mm_heap = dma_heap_add(&exp_info);
	if (IS_ERR(codec_mm_heap))
	return PTR_ERR(codec_mm_heap);
	dma_coerce_mask_and_coherent(dma_heap_get_dev(codec_mm_heap),
	DMA_BIT_MASK(64));
	mb(); /* make sure we only set allocate after dma_mask is set */

	exp_info.name = CODECMM_CACHED_HEAP_NAME;
	exp_info.ops = &codec_mm_heap_ops;
	exp_info.priv = NULL;
	codec_mm_heap = dma_heap_add(&exp_info);
	if (IS_ERR(codec_mm_heap))
	return PTR_ERR(codec_mm_heap);
	dma_coerce_mask_and_coherent(dma_heap_get_dev(codec_mm_heap),
	DMA_BIT_MASK(64));
	mb(); /* make sure we only set allocate after dma_mask is set */

	codec_mm_heap_ops.allocate = codec_mm_heap_allocate;

	pr_info("codecmm dmaheap:enter %s\n", __func__);
	return 0;
	}

	MODULE_LICENSE("GPL v2");