Commit 0104fdbb authored by Chris Wilson's avatar Chris Wilson Committed by Daniel Vetter

drm/i915: Introduce i915_gem_object_create_stolen()

Allow for the creation of GEM objects backed by stolen memory. As these
are not backed by ordinary pages, we create a fake dma mapping and store
the address in the scatterlist rather than obj->pages.

v2: Mark _i915_gem_object_create_stolen() as static, as noticed by Jesse
Barnes.
Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: default avatarBen Widawsky <ben@bwidawsk.net>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent 960e3564
......@@ -1576,6 +1576,9 @@ int i915_gem_init_stolen(struct drm_device *dev);
int i915_gem_stolen_setup_compression(struct drm_device *dev, int size);
void i915_gem_stolen_cleanup_compression(struct drm_device *dev);
void i915_gem_cleanup_stolen(struct drm_device *dev);
struct drm_i915_gem_object *
i915_gem_object_create_stolen(struct drm_device *dev, u32 size);
void i915_gem_object_release_stolen(struct drm_i915_gem_object *obj);
/* i915_gem_tiling.c */
void i915_gem_detect_bit_6_swizzle(struct drm_device *dev);
......
......@@ -3772,6 +3772,7 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
obj->pages_pin_count = 0;
i915_gem_object_put_pages(obj);
i915_gem_object_free_mmap_offset(obj);
i915_gem_object_release_stolen(obj);
BUG_ON(obj->pages);
......
......@@ -192,3 +192,128 @@ int i915_gem_init_stolen(struct drm_device *dev)
return 0;
}
static struct sg_table *
i915_pages_create_for_stolen(struct drm_device *dev,
u32 offset, u32 size)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct sg_table *st;
struct scatterlist *sg;
DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
BUG_ON(offset > dev_priv->mm.gtt->stolen_size - size);
/* We hide that we have no struct page backing our stolen object
* by wrapping the contiguous physical allocation with a fake
* dma mapping in a single scatterlist.
*/
st = kmalloc(sizeof(*st), GFP_KERNEL);
if (st == NULL)
return NULL;
if (sg_alloc_table(st, 1, GFP_KERNEL)) {
kfree(st);
return NULL;
}
sg = st->sgl;
sg->offset = offset;
sg->length = size;
sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
sg_dma_len(sg) = size;
return st;
}
static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
{
BUG();
return -EINVAL;
}
static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
{
/* Should only be called during free */
sg_free_table(obj->pages);
kfree(obj->pages);
}
static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
.get_pages = i915_gem_object_get_pages_stolen,
.put_pages = i915_gem_object_put_pages_stolen,
};
static struct drm_i915_gem_object *
_i915_gem_object_create_stolen(struct drm_device *dev,
struct drm_mm_node *stolen)
{
struct drm_i915_gem_object *obj;
obj = kzalloc(sizeof(*obj), GFP_KERNEL);
if (obj == NULL)
return NULL;
if (drm_gem_private_object_init(dev, &obj->base, stolen->size))
goto cleanup;
i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
obj->pages = i915_pages_create_for_stolen(dev,
stolen->start, stolen->size);
if (obj->pages == NULL)
goto cleanup;
obj->has_dma_mapping = true;
obj->pages_pin_count = 1;
obj->stolen = stolen;
obj->base.write_domain = I915_GEM_DOMAIN_GTT;
obj->base.read_domains = I915_GEM_DOMAIN_GTT;
obj->cache_level = I915_CACHE_NONE;
return obj;
cleanup:
kfree(obj);
return NULL;
}
struct drm_i915_gem_object *
i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_i915_gem_object *obj;
struct drm_mm_node *stolen;
if (dev_priv->mm.stolen_base == 0)
return NULL;
DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
if (size == 0)
return NULL;
stolen = drm_mm_search_free(&dev_priv->mm.stolen, size, 4096, 0);
if (stolen)
stolen = drm_mm_get_block(stolen, size, 4096);
if (stolen == NULL)
return NULL;
obj = _i915_gem_object_create_stolen(dev, stolen);
if (obj)
return obj;
drm_mm_put_block(stolen);
return NULL;
}
void
i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
{
if (obj->stolen) {
drm_mm_put_block(obj->stolen);
obj->stolen = NULL;
}
}
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