[RFC v2 07/20] drm/i915: pre-alloc instead of drm_mm search/get_block

[David Herrmann]

i915 is the last user of the weird search+get_block drm_mm API. Convert it
to an explicit kmalloc()+insert_node().

Signed-off-by: David Herrmann <dh.herrmann at gmail.com>
---
 drivers/gpu/drm/i915/i915_gem.c        |  9 +++--
 drivers/gpu/drm/i915/i915_gem_stolen.c | 72 ++++++++++++++++++++++------------
 2 files changed, 53 insertions(+), 28 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 324f3c5..f7c3b09 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2628,7 +2628,8 @@ i915_gem_object_unbind(struct drm_i915_gem_object *obj)
 	/* Avoid an unnecessary call to unbind on rebind. */
 	obj->map_and_fenceable = true;
 
-	drm_mm_put_block(obj->gtt_space);
+	drm_mm_remove_node(obj->gtt_space);
+	kfree(obj->gtt_space);
 	obj->gtt_space = NULL;
 	obj->gtt_offset = 0;
 
@@ -3146,14 +3147,16 @@ search_free:
 	}
 	if (WARN_ON(!i915_gem_valid_gtt_space(dev, node, obj->cache_level))) {
 		i915_gem_object_unpin_pages(obj);
-		drm_mm_put_block(node);
+		drm_mm_remove_node(node);
+		kfree(node);
 		return -EINVAL;
 	}
 
 	ret = i915_gem_gtt_prepare_object(obj);
 	if (ret) {
 		i915_gem_object_unpin_pages(obj);
-		drm_mm_put_block(node);
+		drm_mm_remove_node(node);
+		kfree(node);
 		return ret;
 	}
 
diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 982d473..820e78f 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -95,31 +95,39 @@ static int i915_setup_compression(struct drm_device *dev, int size)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);
+	int ret;
 
-	/* Try to over-allocate to reduce reallocations and fragmentation */
-	compressed_fb = drm_mm_search_free(&dev_priv->mm.stolen,
-					   size <<= 1, 4096, 0);
-	if (!compressed_fb)
-		compressed_fb = drm_mm_search_free(&dev_priv->mm.stolen,
-						   size >>= 1, 4096, 0);
-	if (compressed_fb)
-		compressed_fb = drm_mm_get_block(compressed_fb, size, 4096);
+	compressed_fb = kzalloc(sizeof(*compressed_fb), GFP_KERNEL);
 	if (!compressed_fb)
 		goto err;
 
+	/* Try to over-allocate to reduce reallocations and fragmentation */
+	ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
+				 size <<= 1, 4096, false);
+	if (ret)
+		ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_fb,
+					 size >>= 1, 4096, false);
+	if (ret) {
+		kfree(compressed_fb);
+		goto err;
+	}
+
 	if (HAS_PCH_SPLIT(dev))
 		I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
 	else if (IS_GM45(dev)) {
 		I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
 	} else {
-		compressed_llb = drm_mm_search_free(&dev_priv->mm.stolen,
-						    4096, 4096, 0);
-		if (compressed_llb)
-			compressed_llb = drm_mm_get_block(compressed_llb,
-							  4096, 4096);
+		compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
 		if (!compressed_llb)
 			goto err_fb;
 
+		ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
+					 4096, 4096, false);
+		if (ret) {
+			kfree(compressed_llb);
+			goto err_fb;
+		}
+
 		dev_priv->compressed_llb = compressed_llb;
 
 		I915_WRITE(FBC_CFB_BASE,
@@ -137,7 +145,8 @@ static int i915_setup_compression(struct drm_device *dev, int size)
 	return 0;
 
 err_fb:
-	drm_mm_put_block(compressed_fb);
+	drm_mm_remove_node(compressed_fb);
+	kfree(compressed_fb);
 err:
 	pr_info_once("drm: not enough stolen space for compressed buffer (need %d more bytes), disabling. Hint: you may be able to increase stolen memory size in the BIOS to avoid this.\n", size);
 	return -ENOSPC;
@@ -166,11 +175,15 @@ void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
 	if (dev_priv->cfb_size == 0)
 		return;
 
-	if (dev_priv->compressed_fb)
-		drm_mm_put_block(dev_priv->compressed_fb);
+	if (dev_priv->compressed_fb) {
+		drm_mm_remove_node(dev_priv->compressed_fb);
+		kfree(dev_priv->compressed_fb);
+	}
 
-	if (dev_priv->compressed_llb)
-		drm_mm_put_block(dev_priv->compressed_llb);
+	if (dev_priv->compressed_llb) {
+		drm_mm_remove_node(dev_priv->compressed_llb);
+		kfree(dev_priv->compressed_llb);
+	}
 
 	dev_priv->cfb_size = 0;
 }
@@ -302,6 +315,7 @@ 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;
+	int ret;
 
 	if (!drm_mm_initialized(&dev_priv->mm.stolen))
 		return NULL;
@@ -310,17 +324,23 @@ i915_gem_object_create_stolen(struct drm_device *dev, u32 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)
+	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
+	if (!stolen)
 		return NULL;
 
+	ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,
+				 4096, false);
+	if (ret) {
+		kfree(stolen);
+		return NULL;
+	}
+
 	obj = _i915_gem_object_create_stolen(dev, stolen);
 	if (obj)
 		return obj;
 
-	drm_mm_put_block(stolen);
+	drm_mm_remove_node(stolen);
+	kfree(stolen);
 	return NULL;
 }
 
@@ -358,7 +378,8 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 	obj = _i915_gem_object_create_stolen(dev, stolen);
 	if (obj == NULL) {
 		DRM_DEBUG_KMS("failed to allocate stolen object\n");
-		drm_mm_put_block(stolen);
+		drm_mm_remove_node(stolen);
+		kfree(stolen);
 		return NULL;
 	}
 
@@ -396,7 +417,8 @@ void
 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 {
 	if (obj->stolen) {
-		drm_mm_put_block(obj->stolen);
+		drm_mm_remove_node(obj->stolen);
+		kfree(obj->stolen);
 		obj->stolen = NULL;
 	}
 }
-- 
1.8.3.2