Commit 2a55e7b5 authored by Laura Abbott's avatar Laura Abbott Committed by Greg Kroah-Hartman
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staging: android: ion: Call dma_map_sg for syncing and mapping 



Technically, calling dma_buf_map_attachment should return a buffer
properly dma_mapped. Add calls to dma_map_sg to begin_cpu_access to
ensure this happens. As a side effect, this lets Ion buffers take
advantage of the dma_buf sync ioctls.

Signed-off-by: default avatarLaura Abbott <labbott@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 17fd283f

drivers/staging/android/ion/ion.c

+102 −49
Original line number Diff line number Diff line
@@ -162,6 +162,7 @@ static struct ion_buffer *ion_buffer_create(struct ion_heap *heap, 
	buffer->dev = dev;

	buffer->size = len;

	INIT_LIST_HEAD(&buffer->vmas);

	INIT_LIST_HEAD(&buffer->attachments);

	mutex_init(&buffer->lock);

	/*

	 * this will set up dma addresses for the sglist -- it is not
@@ -796,10 +797,6 @@ void ion_client_destroy(struct ion_client *client) 
}

EXPORT_SYMBOL(ion_client_destroy);



static void ion_buffer_sync_for_device(struct ion_buffer *buffer,

				       struct device *dev,

				       enum dma_data_direction direction);



static struct sg_table *dup_sg_table(struct sg_table *table)

{

	struct sg_table *new_table;
@@ -826,22 +823,89 @@ static struct sg_table *dup_sg_table(struct sg_table *table) 
	return new_table;

}



static void free_duped_table(struct sg_table *table)

{

	sg_free_table(table);

	kfree(table);

}



struct ion_dma_buf_attachment {

	struct device *dev;

	struct sg_table *table;

	struct list_head list;

};



static int ion_dma_buf_attach(struct dma_buf *dmabuf, struct device *dev,

				struct dma_buf_attachment *attachment)

{

	struct ion_dma_buf_attachment *a;

	struct sg_table *table;

	struct ion_buffer *buffer = dmabuf->priv;



	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 = dev;

	INIT_LIST_HEAD(&a->list);



	attachment->priv = a;



	mutex_lock(&buffer->lock);

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

	mutex_unlock(&buffer->lock);



	return 0;

}



static void ion_dma_buf_detatch(struct dma_buf *dmabuf,

				struct dma_buf_attachment *attachment)

{

	struct ion_dma_buf_attachment *a = attachment->priv;

	struct ion_buffer *buffer = dmabuf->priv;



	free_duped_table(a->table);

	mutex_lock(&buffer->lock);

	list_del(&a->list);

	mutex_unlock(&buffer->lock);



	kfree(a);

}





static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment,

					enum dma_data_direction direction)

{

	struct dma_buf *dmabuf = attachment->dmabuf;

	struct ion_buffer *buffer = dmabuf->priv;

	struct ion_dma_buf_attachment *a = attachment->priv;

	struct sg_table *table;

	int ret;



	table = a->table;



	ion_buffer_sync_for_device(buffer, attachment->dev, direction);

	return dup_sg_table(buffer->sg_table);

	if (!dma_map_sg(attachment->dev, table->sgl, table->nents,

			direction)){

		ret = -ENOMEM;

		goto err;

	}

	return table;



err:

	free_duped_table(table);

	return ERR_PTR(ret);

}



static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment,

			      struct sg_table *table,

			      enum dma_data_direction direction)

{

	sg_free_table(table);

	kfree(table);

	dma_unmap_sg(attachment->dev, table->sgl, table->nents, direction);

}



void ion_pages_sync_for_device(struct device *dev, struct page *page,
@@ -865,38 +929,6 @@ struct ion_vma_list { 
	struct vm_area_struct *vma;

};



static void ion_buffer_sync_for_device(struct ion_buffer *buffer,

				       struct device *dev,

				       enum dma_data_direction dir)

{

	struct ion_vma_list *vma_list;

	int pages = PAGE_ALIGN(buffer->size) / PAGE_SIZE;

	int i;



	pr_debug("%s: syncing for device %s\n", __func__,

		 dev ? dev_name(dev) : "null");



	if (!ion_buffer_fault_user_mappings(buffer))

		return;



	mutex_lock(&buffer->lock);

	for (i = 0; i < pages; i++) {

		struct page *page = buffer->pages[i];



		if (ion_buffer_page_is_dirty(page))

			ion_pages_sync_for_device(dev, ion_buffer_page(page),

						  PAGE_SIZE, dir);



		ion_buffer_page_clean(buffer->pages + i);

	}

	list_for_each_entry(vma_list, &buffer->vmas, list) {

		struct vm_area_struct *vma = vma_list->vma;



		zap_page_range(vma, vma->vm_start, vma->vm_end - vma->vm_start);

	}

	mutex_unlock(&buffer->lock);

}



static int ion_vm_fault(struct vm_fault *vmf)

{

	struct ion_buffer *buffer = vmf->vma->vm_private_data;
@@ -1014,27 +1046,46 @@ static int ion_dma_buf_begin_cpu_access(struct dma_buf *dmabuf, 
{

	struct ion_buffer *buffer = dmabuf->priv;

	void *vaddr;

	struct ion_dma_buf_attachment *a;



	if (!buffer->heap->ops->map_kernel) {

		pr_err("%s: map kernel is not implemented by this heap.\n",

		       __func__);

		return -ENODEV;

	/*

	 * TODO: Move this elsewhere because we don't always need a vaddr

	 */

	if (buffer->heap->ops->map_kernel) {

		mutex_lock(&buffer->lock);

		vaddr = ion_buffer_kmap_get(buffer);

		mutex_unlock(&buffer->lock);

	}





	mutex_lock(&buffer->lock);

	vaddr = ion_buffer_kmap_get(buffer);

	list_for_each_entry(a, &buffer->attachments, list) {

		dma_sync_sg_for_cpu(a->dev, a->table->sgl, a->table->nents,

					DMA_BIDIRECTIONAL);

	}

	mutex_unlock(&buffer->lock);

	return PTR_ERR_OR_ZERO(vaddr);



	return 0;

}



static int ion_dma_buf_end_cpu_access(struct dma_buf *dmabuf,

				      enum dma_data_direction direction)

{

	struct ion_buffer *buffer = dmabuf->priv;

	struct ion_dma_buf_attachment *a;



	if (buffer->heap->ops->map_kernel) {

		mutex_lock(&buffer->lock);

		ion_buffer_kmap_put(buffer);

		mutex_unlock(&buffer->lock);

	}



	mutex_lock(&buffer->lock);

	list_for_each_entry(a, &buffer->attachments, list) {

		dma_sync_sg_for_device(a->dev, a->table->sgl, a->table->nents,

					DMA_BIDIRECTIONAL);

	}

	mutex_unlock(&buffer->lock);



	return 0;

}
@@ -1044,6 +1095,8 @@ static const struct dma_buf_ops dma_buf_ops = { 
	.unmap_dma_buf = ion_unmap_dma_buf,

	.mmap = ion_mmap,

	.release = ion_dma_buf_release,

	.attach = ion_dma_buf_attach,

	.detach = ion_dma_buf_detatch,

	.begin_cpu_access = ion_dma_buf_begin_cpu_access,

	.end_cpu_access = ion_dma_buf_end_cpu_access,

	.kmap_atomic = ion_dma_buf_kmap,

drivers/staging/android/ion/ion_priv.h

+1 −0
Original line number Diff line number Diff line
@@ -72,6 +72,7 @@ struct ion_buffer { 
	struct sg_table *sg_table;

	struct page **pages;

	struct list_head vmas;

	struct list_head attachments;

	/* used to track orphaned buffers */

	int handle_count;

	char task_comm[TASK_COMM_LEN];

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