From 0104fdbb84d7adb0e377ed05bf75eba97b007544 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 15 Nov 2012 11:32:26 +0000 Subject: [PATCH] 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: Chris Wilson Reviewed-by: Jesse Barnes Reviewed-by: Ben Widawsky Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_drv.h | 3 + drivers/gpu/drm/i915/i915_gem.c | 1 + drivers/gpu/drm/i915/i915_gem_stolen.c | 125 +++++++++++++++++++++++++ 3 files changed, 129 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 1646d036db09..d1d68f0b55e8 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -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); diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 5c8df572cd17..3de62b0127a5 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -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); diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c index 10ca473d85f2..7299d632663c 100644 --- a/drivers/gpu/drm/i915/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c @@ -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; + } +} -- 2.39.5