staging: android: ion: Rework heap registration/enumeration

The current model of Ion heap registration  is based on the outdated
model of board files. The replacement for board files (devicetree)
isn't a good replacement for what Ion wants to do. In actuality, Ion
wants to show what memory is available in the system for something else
to figure out what to use. Switch to a model where Ion creates its
device unconditionally and heaps are registed as available regions.
Currently, only system and CMA heaps are converted over to the new
model. Carveout and chunk heaps can be converted over when someone wants
to figure out how.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 12 insertions, 16 deletions

diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index e1fb86530c96..7d402334a546 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -40,6 +40,9 @@
 
 #include "ion.h"
 
+static struct ion_device *internal_dev;
+static int heap_id = 0;
+
 bool ion_buffer_cached(struct ion_buffer *buffer)
 {
 	return !!(buffer->flags & ION_FLAG_CACHED);
@@ -1198,9 +1201,10 @@ static int debug_shrink_get(void *data, u64 *val)
 DEFINE_SIMPLE_ATTRIBUTE(debug_shrink_fops, debug_shrink_get,
 			debug_shrink_set, "%llu\n");
 
-void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap)
+void ion_device_add_heap(struct ion_heap *heap)
 {
 	struct dentry *debug_file;
+	struct ion_device *dev = internal_dev;
 
 	if (!heap->ops->allocate || !heap->ops->free)
 		pr_err("%s: can not add heap with invalid ops struct.\n",
@@ -1217,6 +1221,7 @@ void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap)
 
 	heap->dev = dev;
 	down_write(&dev->lock);
+	heap->id = heap_id++;
 	/*
 	 * use negative heap->id to reverse the priority -- when traversing
 	 * the list later attempt higher id numbers first
@@ -1256,14 +1261,14 @@ void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap)
 }
 EXPORT_SYMBOL(ion_device_add_heap);
 
-struct ion_device *ion_device_create(void)
+int ion_device_create(void)
 {
 	struct ion_device *idev;
 	int ret;
 
 	idev = kzalloc(sizeof(*idev), GFP_KERNEL);
 	if (!idev)
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 
 	idev->dev.minor = MISC_DYNAMIC_MINOR;
 	idev->dev.name = "ion";
@@ -1273,7 +1278,7 @@ struct ion_device *ion_device_create(void)
 	if (ret) {
 		pr_err("ion: failed to register misc device.\n");
 		kfree(idev);
-		return ERR_PTR(ret);
+		return ret;
 	}
 
 	idev->debug_root = debugfs_create_dir("ion", NULL);
@@ -1292,7 +1297,6 @@ struct ion_device *ion_device_create(void)
 		pr_err("ion: failed to create debugfs clients directory.\n");
 
 debugfs_done:
-
 	idev->buffers = RB_ROOT;
 	mutex_init(&idev->buffer_lock);
 	init_rwsem(&idev->lock);
@@ -1300,15 +1304,7 @@ debugfs_done:
 	idev->clients = RB_ROOT;
 	ion_root_client = &idev->clients;
 	mutex_init(&debugfs_mutex);
-	return idev;
-}
-EXPORT_SYMBOL(ion_device_create);
-
-void ion_device_destroy(struct ion_device *dev)
-{
-	misc_deregister(&dev->dev);
-	debugfs_remove_recursive(dev->debug_root);
-	/* XXX need to free the heaps and clients ? */
-	kfree(dev);
+	internal_dev = idev;
+	return 0;
 }
-EXPORT_SYMBOL(ion_device_destroy);
+subsys_initcall(ion_device_create);