[PATCH 1/3] drm: add mmap function to prime helpers

[PATCH 1/3] drm: add mmap function to prime helpers

[Joonyoung Shim]

This adds to call low-level mmap() from prime helpers.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
---
 drivers/gpu/drm/drm_prime.c | 5 ++++-
 include/drm/drmP.h          | 2 ++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index d92853e..3a008b2 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -165,7 +165,10 @@ static void drm_gem_dmabuf_kunmap(struct dma_buf *dma_buf,
 static int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf,
 		struct vm_area_struct *vma)
 {
-	return -EINVAL;
+	struct drm_gem_object *obj = dma_buf->priv;
+	struct drm_device *dev = obj->dev;
+
+	return dev->driver->gem_prime_mmap(obj, vma);
 }
 
 static const struct dma_buf_ops drm_gem_prime_dmabuf_ops =  {
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 82670ac..12083dc 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -937,6 +937,8 @@ struct drm_driver {
 				struct sg_table *sgt);
 	void *(*gem_prime_vmap)(struct drm_gem_object *obj);
 	void (*gem_prime_vunmap)(struct drm_gem_object *obj, void *vaddr);
+	int (*gem_prime_mmap)(struct drm_gem_object *obj,
+				struct vm_area_struct *vma);
 
 	/* vga arb irq handler */
 	void (*vgaarb_irq)(struct drm_device *dev, bool state);
-- 
1.8.1.2

[PATCH 2/3] drm/cma: add low-level hook functions to use prime helpers

[Joonyoung Shim]

Instead of using the dma_buf functionality for GEM CMA, we can use prime
helpers if we can provide low-level hook functions for GEM CMA.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
---
 drivers/gpu/drm/drm_gem_cma_helper.c | 76 ++++++++++++++++++++++++++++++++++++
 include/drm/drm_gem_cma_helper.h     |  9 +++++
 2 files changed, 85 insertions(+)

diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
index 9efabce..41a4635 100644
--- a/drivers/gpu/drm/drm_gem_cma_helper.c
+++ b/drivers/gpu/drm/drm_gem_cma_helper.c
@@ -599,3 +599,79 @@ error_gem_free:
 	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(drm_gem_cma_dmabuf_import);
+
+/* low-level interface prime helpers */
+struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)
+{
+	struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
+	struct sg_table *sgt;
+	int ret;
+
+	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
+	if (!sgt)
+		return NULL;
+
+	ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,
+			      cma_obj->paddr, obj->size);
+	if (ret < 0)
+		goto out;
+
+	return sgt;
+
+out:
+	kfree(sgt);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_get_sg_table);
+
+struct drm_gem_object *
+drm_gem_cma_prime_import_sg_table(struct drm_device *dev, size_t size,
+				  struct sg_table *sgt)
+{
+	struct drm_gem_cma_object *cma_obj;
+
+	if (sgt->nents != 1)
+		return ERR_PTR(-EINVAL);
+
+	/* Create a CMA GEM buffer. */
+	cma_obj = __drm_gem_cma_create(dev, size);
+	if (IS_ERR(cma_obj))
+		return ERR_PTR(PTR_ERR(cma_obj));
+
+	cma_obj->paddr = sg_dma_address(sgt->sgl);
+	cma_obj->sgt = sgt;
+
+	DRM_DEBUG_PRIME("dma_addr = 0x%x, size = %zu\n", cma_obj->paddr, size);
+
+	return &cma_obj->base;
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_import_sg_table);
+
+int drm_gem_cma_prime_mmap(struct drm_gem_object *obj,
+			   struct vm_area_struct *vma)
+{
+	struct drm_gem_cma_object *cma_obj;
+	int ret;
+
+	ret = drm_gem_mmap_obj(obj, obj->size, vma);
+	if (ret < 0)
+		return ret;
+
+	cma_obj = to_drm_gem_cma_obj(obj);
+	return drm_gem_cma_mmap_obj(cma_obj, vma);
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_mmap);
+
+void *drm_gem_cma_prime_vmap(struct drm_gem_object *obj)
+{
+	struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
+
+	return cma_obj->vaddr;
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vmap);
+
+void drm_gem_cma_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
+{
+	/* Nothing to do */
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vunmap);
diff --git a/include/drm/drm_gem_cma_helper.h b/include/drm/drm_gem_cma_helper.h
index 6e17251..9d39d2a 100644
--- a/include/drm/drm_gem_cma_helper.h
+++ b/include/drm/drm_gem_cma_helper.h
@@ -54,4 +54,13 @@ struct dma_buf *drm_gem_cma_dmabuf_export(struct drm_device *drm_dev,
 struct drm_gem_object *drm_gem_cma_dmabuf_import(struct drm_device *drm_dev,
 						 struct dma_buf *dma_buf);
 
+struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj);
+struct drm_gem_object *
+drm_gem_cma_prime_import_sg_table(struct drm_device *dev, size_t size,
+				  struct sg_table *sgt);
+int drm_gem_cma_prime_mmap(struct drm_gem_object *obj,
+			   struct vm_area_struct *vma);
+void *drm_gem_cma_prime_vmap(struct drm_gem_object *obj);
+void drm_gem_cma_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
+
 #endif /* __DRM_GEM_CMA_HELPER_H__ */
-- 
1.8.1.2

[PATCH 3/3] drm/cma: remove GEM CMA specific dma_buf functionality

[Joonyoung Shim]

We can use prime helpers instead.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
---
 drivers/gpu/drm/drm_gem_cma_helper.c | 283 -----------------------------------
 include/drm/drm_gem_cma_helper.h     |   6 -
 2 files changed, 289 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
index 41a4635..076b045 100644
--- a/drivers/gpu/drm/drm_gem_cma_helper.c
+++ b/drivers/gpu/drm/drm_gem_cma_helper.c
@@ -317,289 +317,6 @@ void drm_gem_cma_describe(struct drm_gem_cma_object *cma_obj, struct seq_file *m
 EXPORT_SYMBOL_GPL(drm_gem_cma_describe);
 #endif
 
-/* -----------------------------------------------------------------------------
- * DMA-BUF
- */
-
-struct drm_gem_cma_dmabuf_attachment {
-	struct sg_table sgt;
-	enum dma_data_direction dir;
-};
-
-static int drm_gem_cma_dmabuf_attach(struct dma_buf *dmabuf, struct device *dev,
-				     struct dma_buf_attachment *attach)
-{
-	struct drm_gem_cma_dmabuf_attachment *cma_attach;
-
-	cma_attach = kzalloc(sizeof(*cma_attach), GFP_KERNEL);
-	if (!cma_attach)
-		return -ENOMEM;
-
-	cma_attach->dir = DMA_NONE;
-	attach->priv = cma_attach;
-
-	return 0;
-}
-
-static void drm_gem_cma_dmabuf_detach(struct dma_buf *dmabuf,
-				      struct dma_buf_attachment *attach)
-{
-	struct drm_gem_cma_dmabuf_attachment *cma_attach = attach->priv;
-	struct sg_table *sgt;
-
-	if (cma_attach == NULL)
-		return;
-
-	sgt = &cma_attach->sgt;
-
-	if (cma_attach->dir != DMA_NONE)
-		dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents,
-				cma_attach->dir);
-
-	sg_free_table(sgt);
-	kfree(cma_attach);
-	attach->priv = NULL;
-}
-
-static struct sg_table *
-drm_gem_cma_dmabuf_map(struct dma_buf_attachment *attach,
-		       enum dma_data_direction dir)
-{
-	struct drm_gem_cma_dmabuf_attachment *cma_attach = attach->priv;
-	struct drm_gem_cma_object *cma_obj = attach->dmabuf->priv;
-	struct drm_device *drm = cma_obj->base.dev;
-	struct scatterlist *rd, *wr;
-	struct sg_table *sgt;
-	unsigned int i;
-	int nents, ret;
-
-	DRM_DEBUG_PRIME("\n");
-
-	if (WARN_ON(dir == DMA_NONE))
-		return ERR_PTR(-EINVAL);
-
-	/* Return the cached mapping when possible. */
-	if (cma_attach->dir == dir)
-		return &cma_attach->sgt;
-
-	/* Two mappings with different directions for the same attachment are
-	 * not allowed.
-	 */
-	if (WARN_ON(cma_attach->dir != DMA_NONE))
-		return ERR_PTR(-EBUSY);
-
-	sgt = &cma_attach->sgt;
-
-	ret = sg_alloc_table(sgt, cma_obj->sgt->orig_nents, GFP_KERNEL);
-	if (ret) {
-		DRM_ERROR("failed to alloc sgt.\n");
-		return ERR_PTR(-ENOMEM);
-	}
-
-	mutex_lock(&drm->struct_mutex);
-
-	rd = cma_obj->sgt->sgl;
-	wr = sgt->sgl;
-	for (i = 0; i < sgt->orig_nents; ++i) {
-		sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
-		rd = sg_next(rd);
-		wr = sg_next(wr);
-	}
-
-	nents = dma_map_sg(attach->dev, sgt->sgl, sgt->orig_nents, dir);
-	if (!nents) {
-		DRM_ERROR("failed to map sgl with iommu.\n");
-		sg_free_table(sgt);
-		sgt = ERR_PTR(-EIO);
-		goto done;
-	}
-
-	cma_attach->dir = dir;
-	attach->priv = cma_attach;
-
-	DRM_DEBUG_PRIME("buffer size = %zu\n", cma_obj->base.size);
-
-done:
-	mutex_unlock(&drm->struct_mutex);
-	return sgt;
-}
-
-static void drm_gem_cma_dmabuf_unmap(struct dma_buf_attachment *attach,
-				     struct sg_table *sgt,
-				     enum dma_data_direction dir)
-{
-	/* Nothing to do. */
-}
-
-static void drm_gem_cma_dmabuf_release(struct dma_buf *dmabuf)
-{
-	struct drm_gem_cma_object *cma_obj = dmabuf->priv;
-
-	DRM_DEBUG_PRIME("%s\n", __FILE__);
-
-	/*
-	 * drm_gem_cma_dmabuf_release() call means that file object's
-	 * f_count is 0 and it calls drm_gem_object_handle_unreference()
-	 * to drop the references that these values had been increased
-	 * at drm_prime_handle_to_fd()
-	 */
-	if (cma_obj->base.export_dma_buf == dmabuf) {
-		cma_obj->base.export_dma_buf = NULL;
-
-		/*
-		 * drop this gem object refcount to release allocated buffer
-		 * and resources.
-		 */
-		drm_gem_object_unreference_unlocked(&cma_obj->base);
-	}
-}
-
-static void *drm_gem_cma_dmabuf_kmap_atomic(struct dma_buf *dmabuf,
-					    unsigned long page_num)
-{
-	/* TODO */
-
-	return NULL;
-}
-
-static void drm_gem_cma_dmabuf_kunmap_atomic(struct dma_buf *dmabuf,
-					     unsigned long page_num, void *addr)
-{
-	/* TODO */
-}
-
-static void *drm_gem_cma_dmabuf_kmap(struct dma_buf *dmabuf,
-				     unsigned long page_num)
-{
-	/* TODO */
-
-	return NULL;
-}
-
-static void drm_gem_cma_dmabuf_kunmap(struct dma_buf *dmabuf,
-				      unsigned long page_num, void *addr)
-{
-	/* TODO */
-}
-
-static int drm_gem_cma_dmabuf_mmap(struct dma_buf *dmabuf,
-				   struct vm_area_struct *vma)
-{
-	struct drm_gem_cma_object *cma_obj = dmabuf->priv;
-	struct drm_gem_object *gem_obj = &cma_obj->base;
-	int ret;
-
-	ret = drm_gem_mmap_obj(gem_obj, gem_obj->size, vma);
-	if (ret < 0)
-		return ret;
-
-	return drm_gem_cma_mmap_obj(cma_obj, vma);
-}
-
-static void *drm_gem_cma_dmabuf_vmap(struct dma_buf *dmabuf)
-{
-	struct drm_gem_cma_object *cma_obj = dmabuf->priv;
-
-	return cma_obj->vaddr;
-}
-
-static struct dma_buf_ops drm_gem_cma_dmabuf_ops = {
-	.attach			= drm_gem_cma_dmabuf_attach,
-	.detach			= drm_gem_cma_dmabuf_detach,
-	.map_dma_buf		= drm_gem_cma_dmabuf_map,
-	.unmap_dma_buf		= drm_gem_cma_dmabuf_unmap,
-	.kmap			= drm_gem_cma_dmabuf_kmap,
-	.kmap_atomic		= drm_gem_cma_dmabuf_kmap_atomic,
-	.kunmap			= drm_gem_cma_dmabuf_kunmap,
-	.kunmap_atomic		= drm_gem_cma_dmabuf_kunmap_atomic,
-	.mmap			= drm_gem_cma_dmabuf_mmap,
-	.vmap			= drm_gem_cma_dmabuf_vmap,
-	.release		= drm_gem_cma_dmabuf_release,
-};
-
-struct dma_buf *drm_gem_cma_dmabuf_export(struct drm_device *drm,
-					  struct drm_gem_object *obj, int flags)
-{
-	struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
-
-	return dma_buf_export(cma_obj, &drm_gem_cma_dmabuf_ops,
-			      cma_obj->base.size, flags);
-}
-EXPORT_SYMBOL_GPL(drm_gem_cma_dmabuf_export);
-
-struct drm_gem_object *drm_gem_cma_dmabuf_import(struct drm_device *drm,
-						 struct dma_buf *dma_buf)
-{
-	struct drm_gem_cma_object *cma_obj;
-	struct dma_buf_attachment *attach;
-	struct sg_table *sgt;
-	int ret;
-
-	DRM_DEBUG_PRIME("%s\n", __FILE__);
-
-	/* is this one of own objects? */
-	if (dma_buf->ops == &drm_gem_cma_dmabuf_ops) {
-		struct drm_gem_object *obj;
-
-		cma_obj = dma_buf->priv;
-		obj = &cma_obj->base;
-
-		/* is it from our device? */
-		if (obj->dev == drm) {
-			/*
-			 * Importing dmabuf exported from out own gem increases
-			 * refcount on gem itself instead of f_count of dmabuf.
-			 */
-			drm_gem_object_reference(obj);
-			dma_buf_put(dma_buf);
-			return obj;
-		}
-	}
-
-	/* Create a CMA GEM buffer. */
-	cma_obj = __drm_gem_cma_create(drm, dma_buf->size);
-	if (IS_ERR(cma_obj))
-		return ERR_PTR(PTR_ERR(cma_obj));
-
-	/* Attach to the buffer and map it. Make sure the mapping is contiguous
-	 * on the device memory bus, as that's all we support.
-	 */
-	attach = dma_buf_attach(dma_buf, drm->dev);
-	if (IS_ERR(attach)) {
-		ret = -EINVAL;
-		goto error_gem_free;
-	}
-
-	sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
-	if (IS_ERR_OR_NULL(sgt)) {
-		ret = sgt ? PTR_ERR(sgt) : -ENOMEM;
-		goto error_buf_detach;
-	}
-
-	if (sgt->nents != 1) {
-		ret = -EINVAL;
-		goto error_buf_unmap;
-	}
-
-	cma_obj->base.import_attach = attach;
-	cma_obj->paddr = sg_dma_address(sgt->sgl);
-	cma_obj->sgt = sgt;
-
-	DRM_DEBUG_PRIME("dma_addr = 0x%x, size = %zu\n", cma_obj->paddr,
-			dma_buf->size);
-
-	return &cma_obj->base;
-
-error_buf_unmap:
-	dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
-error_buf_detach:
-	dma_buf_detach(dma_buf, attach);
-error_gem_free:
-	drm_gem_cma_free_object(&cma_obj->base);
-	return ERR_PTR(ret);
-}
-EXPORT_SYMBOL_GPL(drm_gem_cma_dmabuf_import);
-
 /* low-level interface prime helpers */
 struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)
 {
diff --git a/include/drm/drm_gem_cma_helper.h b/include/drm/drm_gem_cma_helper.h
index 9d39d2a..c34f27f 100644
--- a/include/drm/drm_gem_cma_helper.h
+++ b/include/drm/drm_gem_cma_helper.h
@@ -48,12 +48,6 @@ extern const struct vm_operations_struct drm_gem_cma_vm_ops;
 void drm_gem_cma_describe(struct drm_gem_cma_object *obj, struct seq_file *m);
 #endif
 
-struct dma_buf *drm_gem_cma_dmabuf_export(struct drm_device *drm_dev,
-					  struct drm_gem_object *obj,
-					  int flags);
-struct drm_gem_object *drm_gem_cma_dmabuf_import(struct drm_device *drm_dev,
-						 struct dma_buf *dma_buf);
-
 struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj);
 struct drm_gem_object *
 drm_gem_cma_prime_import_sg_table(struct drm_device *dev, size_t size,
-- 
1.8.1.2

Re: [PATCH 1/3] drm: add mmap function to prime helpers

[Aaron Plattner]

On 06/12/2013 06:16 AM, Joonyoung Shim wrote:
> This adds to call low-level mmap() from prime helpers.
>
> Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
> ---
>   drivers/gpu/drm/drm_prime.c | 5 ++++-
>   include/drm/drmP.h          | 2 ++
>   2 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
> index d92853e..3a008b2 100644
> --- a/drivers/gpu/drm/drm_prime.c
> +++ b/drivers/gpu/drm/drm_prime.c
> @@ -165,7 +165,10 @@ static void drm_gem_dmabuf_kunmap(struct dma_buf *dma_buf,
>   static int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf,
>   		struct vm_area_struct *vma)
>   {
> -	return -EINVAL;
> +	struct drm_gem_object *obj = dma_buf->priv;
> +	struct drm_device *dev = obj->dev;
> +
> +	return dev->driver->gem_prime_mmap(obj, vma);

Won't this crash if the driver doesn't fill in the new field and 
userspace tries to map it?

>   }
>
>   static const struct dma_buf_ops drm_gem_prime_dmabuf_ops =  {
> diff --git a/include/drm/drmP.h b/include/drm/drmP.h
> index 82670ac..12083dc 100644
> --- a/include/drm/drmP.h
> +++ b/include/drm/drmP.h
> @@ -937,6 +937,8 @@ struct drm_driver {
>   				struct sg_table *sgt);
>   	void *(*gem_prime_vmap)(struct drm_gem_object *obj);
>   	void (*gem_prime_vunmap)(struct drm_gem_object *obj, void *vaddr);
> +	int (*gem_prime_mmap)(struct drm_gem_object *obj,
> +				struct vm_area_struct *vma);
>
>   	/* vga arb irq handler */
>   	void (*vgaarb_irq)(struct drm_device *dev, bool state);
>

-- 
Aaron

Re: [PATCH 1/3] drm: add mmap function to prime helpers

[Joonyoung Shim]

On 06/15/2013 02:16 AM, Aaron Plattner wrote:
> On 06/12/2013 06:16 AM, Joonyoung Shim wrote:
>> This adds to call low-level mmap() from prime helpers.
>>
>> Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
>> ---
>>   drivers/gpu/drm/drm_prime.c | 5 ++++-
>>   include/drm/drmP.h          | 2 ++
>>   2 files changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
>> index d92853e..3a008b2 100644
>> --- a/drivers/gpu/drm/drm_prime.c
>> +++ b/drivers/gpu/drm/drm_prime.c
>> @@ -165,7 +165,10 @@ static void drm_gem_dmabuf_kunmap(struct dma_buf 
>> *dma_buf,
>>   static int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf,
>>           struct vm_area_struct *vma)
>>   {
>> -    return -EINVAL;
>> +    struct drm_gem_object *obj = dma_buf->priv;
>> +    struct drm_device *dev = obj->dev;
>> +
>> +    return dev->driver->gem_prime_mmap(obj, vma);
>
> Won't this crash if the driver doesn't fill in the new field and 
> userspace tries to map it?
>

Right, if gem_prime_mmap field is NULL, should return error.

Thanks for comments.