Re: [PATCH v2 3/5] drm: GEM CMA: Split object creation into object alloc and DMA memory alloc

On Mon, Jun 3, 2013 at 10:20 PM, Laurent Pinchart laurent.pinchart+renesas@ideasonboard.com wrote:

This allows creating a GEM CMA object without an associated DMA memory buffer, and will be used to implement DRM PRIME support.

Signed-off-by: Laurent Pinchart laurent.pinchart+renesas@ideasonboard.com

Reviewed-by: Rob Clark robdclark@gmail.com

---

drivers/gpu/drm/drm_gem_cma_helper.c | 83 +++++++++++++++++++++--------------- 1 file changed, 48 insertions(+), 35 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c index 0a7e011..8cce330 100644 --- a/drivers/gpu/drm/drm_gem_cma_helper.c +++ b/drivers/gpu/drm/drm_gem_cma_helper.c @@ -32,62 +32,73 @@ static unsigned int get_gem_mmap_offset(struct drm_gem_object *obj) return (unsigned int)obj->map_list.hash.key << PAGE_SHIFT; }

-static void drm_gem_cma_buf_destroy(struct drm_device *drm,

•           struct drm_gem_cma_object *cma_obj)
  

-{

•   dma_free_writecombine(drm->dev, cma_obj->base.size, cma_obj->vaddr,
  

•                   cma_obj->paddr);
  

-}

/*

• • drm_gem_cma_create - allocate an object with the given size

• • __drm_gem_cma_create - Create a GEM CMA object without allocating memory
• • @drm: The drm device
• • @size: The GEM object size

• • returns a struct drm_gem_cma_object* on success or ERR_PTR values
• • on failure.

• • This function creates and initializes a GEM CMA object of the given size, but
• • doesn't allocate any memory to back the object.
• • Return a struct drm_gem_cma_object* on success or ERR_PTR values on failure.
  */

-struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm,

•           unsigned int size)
  

+static struct drm_gem_cma_object * +__drm_gem_cma_create(struct drm_device *drm, unsigned int size) { struct drm_gem_cma_object *cma_obj; struct drm_gem_object *gem_obj; int ret;

•   size = round_up(size, PAGE_SIZE);
  

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

•   cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size,
  

•                   &cma_obj->paddr, GFP_KERNEL | __GFP_NOWARN);
  

•   if (!cma_obj->vaddr) {
  

•           dev_err(drm->dev, "failed to allocate buffer with size %d\n", size);
  

•           ret = -ENOMEM;
  

•           goto err_dma_alloc;
  

•   }
  

•   gem_obj = &cma_obj->base;
  
    ret = drm_gem_object_init(drm, gem_obj, size);
    if (ret)
  

•           goto err_obj_init;
  

•           goto error;
  
    ret = drm_gem_create_mmap_offset(gem_obj);
  

•   if (ret)
  

•           goto err_create_mmap_offset;
  

•   if (ret) {
  

•           drm_gem_object_release(gem_obj);
  

•           goto error;
  

•   }
  
    return cma_obj;
  
  

-err_create_mmap_offset:

•   drm_gem_object_release(gem_obj);
  

+error:

•   kfree(cma_obj);
  

•   return ERR_PTR(ret);
  

+}

-err_obj_init:

•   drm_gem_cma_buf_destroy(drm, cma_obj);
  

+/*

• • drm_gem_cma_create - allocate an object with the given size
• • returns a struct drm_gem_cma_object* on success or ERR_PTR values
• • on failure.
• */

+struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm,

•           unsigned int size)
  

+{

•   struct drm_gem_cma_object *cma_obj;
  
  

-err_dma_alloc:

•   kfree(cma_obj);
  

•   size = round_up(size, PAGE_SIZE);
  
  

•   return ERR_PTR(ret);
  

•   cma_obj = __drm_gem_cma_create(drm, size);
  

•   if (IS_ERR(cma_obj))
  

•           return cma_obj;
  

•   cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size,
  

•                   &cma_obj->paddr, GFP_KERNEL | __GFP_NOWARN);
  

•   if (!cma_obj->vaddr) {
  

•           dev_err(drm->dev, "failed to allocate buffer with size %d\n",
  

•                   size);
  

•           drm_gem_cma_free_object(&cma_obj->base);
  

•           return ERR_PTR(-ENOMEM);
  

•   }
  

•   return cma_obj;
  

} EXPORT_SYMBOL_GPL(drm_gem_cma_create);

@@ -143,11 +154,13 @@ void drm_gem_cma_free_object(struct drm_gem_object *gem_obj) if (gem_obj->map_list.map) drm_gem_free_mmap_offset(gem_obj);

•   drm_gem_object_release(gem_obj);
  

•   cma_obj = to_drm_gem_cma_obj(gem_obj);
  
  

•   drm_gem_cma_buf_destroy(gem_obj->dev, cma_obj);
  

•   if (cma_obj->vaddr)
  

•           dma_free_writecombine(gem_obj->dev->dev, cma_obj->base.size,
  

•                                 cma_obj->vaddr, cma_obj->paddr);
  

•   drm_gem_object_release(gem_obj);
  
    kfree(cma_obj);
  

}

1.8.1.5