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The current model of Ion heap registration is based on the outdated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 <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/android/ion/Kconfig

···
 	  If you're not using Android its probably safe to
 	  say N here.
 
+config ION_SYSTEM_HEAP
+	bool "Ion system heap"
+	depends on ION
+	help
+	  Choose this option to enable the Ion system heap. The system heap
+	  is backed by pages from the buddy allocator. If in doubt, say Y.
+
+config ION_CARVEOUT_HEAP
+	bool "Ion carveout heap support"
+	depends on ION
+	help
+	  Choose this option to enable carveout heaps with Ion. Carveout heaps
+	  are backed by memory reserved from the system. Allocation times are
+	  typically faster at the cost of memory not being used. Unless you
+	  know your system has these regions, you should say N here.
+
+config ION_CHUNK_HEAP
+	bool "Ion chunk heap support"
+	depends on ION
+	help
+          Choose this option to enable chunk heaps with Ion. This heap is
+	  similar in function the carveout heap but memory is broken down
+	  into smaller chunk sizes, typically corresponding to a TLB size.
+	  Unless you know your system has these regions, you should say N here.
+
 config ION_CMA_HEAP
 	bool "Ion CMA heap support"
 	depends on ION && CMA

drivers/staging/android/ion/Makefile

···
-obj-$(CONFIG_ION) +=	ion.o ion-ioctl.o ion_heap.o \
-			ion_page_pool.o ion_system_heap.o \
-			ion_carveout_heap.o ion_chunk_heap.o
+obj-$(CONFIG_ION) +=	ion.o ion-ioctl.o ion_heap.o
+obj-$(CONFIG_ION_SYSTEM_HEAP) += ion_system_heap.o ion_page_pool.o
+obj-$(CONFIG_ION_CARVEOUT_HEAP) += ion_carveout_heap.o
+obj-$(CONFIG_ION_CHUNK_HEAP) += ion_chunk_heap.o
 obj-$(CONFIG_ION_CMA_HEAP) += ion_cma_heap.o

drivers/staging/android/ion/ion.c

···
 
 #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);
···
 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",
···
 
 	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
···
 }
 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";
···
 	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);
···
 		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);
···
 	idev->clients = RB_ROOT;
 	ion_root_client = &idev->clients;
 	mutex_init(&debugfs_mutex);
-	return idev;
+	internal_dev = idev;
+	return 0;
 }
-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);
-}
-EXPORT_SYMBOL(ion_device_destroy);
+subsys_initcall(ion_device_create);

drivers/staging/android/ion/ion.h

···
 bool ion_buffer_fault_user_mappings(struct ion_buffer *buffer);
 
 /**
- * ion_device_create - allocates and returns an ion device
- *
- * returns a valid device or -PTR_ERR
- */
-struct ion_device *ion_device_create(void);
-
-/**
- * ion_device_destroy - free and device and it's resource
- * @dev:		the device
- */
-void ion_device_destroy(struct ion_device *dev);
-
-/**
  * ion_device_add_heap - adds a heap to the ion device
- * @dev:		the device
  * @heap:		the heap to add
  */
-void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap);
+void ion_device_add_heap(struct ion_heap *heap);
 
 /**
  * some helpers for common operations on buffers using the sg_table
···
  */
 size_t ion_heap_freelist_size(struct ion_heap *heap);
 
-
-/**
- * functions for creating and destroying the built in ion heaps.
- * architectures can add their own custom architecture specific
- * heaps as appropriate.
- */
-
-
-struct ion_heap *ion_heap_create(struct ion_platform_heap *heap_data);
-void ion_heap_destroy(struct ion_heap *heap);
-
-struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused);
-void ion_system_heap_destroy(struct ion_heap *heap);
-struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *heap);
-void ion_system_contig_heap_destroy(struct ion_heap *heap);
-
-struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *heap_data);
-void ion_carveout_heap_destroy(struct ion_heap *heap);
-
-struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *heap_data);
-void ion_chunk_heap_destroy(struct ion_heap *heap);
-
-struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *data);
-void ion_cma_heap_destroy(struct ion_heap *heap);
 
 /**
  * functions for creating and destroying a heap pool -- allows you

drivers/staging/android/ion/ion_carveout_heap.c

···
 
 	return &carveout_heap->heap;
 }
-
-void ion_carveout_heap_destroy(struct ion_heap *heap)
-{
-	struct ion_carveout_heap *carveout_heap =
-	     container_of(heap, struct  ion_carveout_heap, heap);
-
-	gen_pool_destroy(carveout_heap->pool);
-	kfree(carveout_heap);
-	carveout_heap = NULL;
-}

drivers/staging/android/ion/ion_chunk_heap.c

···
 	return ERR_PTR(ret);
 }
 
-void ion_chunk_heap_destroy(struct ion_heap *heap)
-{
-	struct ion_chunk_heap *chunk_heap =
-	     container_of(heap, struct  ion_chunk_heap, heap);
-
-	gen_pool_destroy(chunk_heap->pool);
-	kfree(chunk_heap);
-	chunk_heap = NULL;
-}

drivers/staging/android/ion/ion_cma_heap.c

···
 	.unmap_kernel = ion_heap_unmap_kernel,
 };
 
-struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *data)
+static struct ion_heap *__ion_cma_heap_create(struct cma *cma)
 {
 	struct ion_cma_heap *cma_heap;
 
···
 	 * get device from private heaps data, later it will be
 	 * used to make the link with reserved CMA memory
 	 */
-	cma_heap->cma = data->priv;
+	cma_heap->cma = cma;
 	cma_heap->heap.type = ION_HEAP_TYPE_DMA;
 	return &cma_heap->heap;
 }
 
-void ion_cma_heap_destroy(struct ion_heap *heap)
+int __ion_add_cma_heaps(struct cma *cma, void *data)
 {
-	struct ion_cma_heap *cma_heap = to_cma_heap(heap);
+        struct ion_heap *heap;
 
-	kfree(cma_heap);
+	heap = __ion_cma_heap_create(cma);
+	if (IS_ERR(heap))
+		return PTR_ERR(heap);
+
+	heap->name = cma_get_name(cma);
+
+        ion_device_add_heap(heap);
+        return 0;
 }
+
+static int ion_add_cma_heaps(void)
+{
+	cma_for_each_area(__ion_add_cma_heaps, NULL);
+	return 0;
+}
+device_initcall(ion_add_cma_heaps);

drivers/staging/android/ion/ion_heap.c

···
 	heap->shrinker.batch = 0;
 	register_shrinker(&heap->shrinker);
 }
-
-struct ion_heap *ion_heap_create(struct ion_platform_heap *heap_data)
-{
-	struct ion_heap *heap = NULL;
-
-	switch (heap_data->type) {
-	case ION_HEAP_TYPE_SYSTEM_CONTIG:
-		heap = ion_system_contig_heap_create(heap_data);
-		break;
-	case ION_HEAP_TYPE_SYSTEM:
-		heap = ion_system_heap_create(heap_data);
-		break;
-	case ION_HEAP_TYPE_CARVEOUT:
-		heap = ion_carveout_heap_create(heap_data);
-		break;
-	case ION_HEAP_TYPE_CHUNK:
-		heap = ion_chunk_heap_create(heap_data);
-		break;
-#ifdef CONFIG_ION_CMA_HEAP
-	case ION_HEAP_TYPE_DMA:
-		heap = ion_cma_heap_create(heap_data);
-		break;
-#endif
-	default:
-		pr_err("%s: Invalid heap type %d\n", __func__,
-		       heap_data->type);
-		return ERR_PTR(-EINVAL);
-	}
-
-	if (IS_ERR_OR_NULL(heap)) {
-		pr_err("%s: error creating heap %s type %d base %pa size %zu\n",
-		       __func__, heap_data->name, heap_data->type,
-		       &heap_data->base, heap_data->size);
-		return ERR_PTR(-EINVAL);
-	}
-
-	heap->name = heap_data->name;
-	heap->id = heap_data->id;
-	return heap;
-}
-EXPORT_SYMBOL(ion_heap_create);
-
-void ion_heap_destroy(struct ion_heap *heap)
-{
-	if (!heap)
-		return;
-
-	switch (heap->type) {
-	case ION_HEAP_TYPE_SYSTEM_CONTIG:
-		ion_system_contig_heap_destroy(heap);
-		break;
-	case ION_HEAP_TYPE_SYSTEM:
-		ion_system_heap_destroy(heap);
-		break;
-	case ION_HEAP_TYPE_CARVEOUT:
-		ion_carveout_heap_destroy(heap);
-		break;
-	case ION_HEAP_TYPE_CHUNK:
-		ion_chunk_heap_destroy(heap);
-		break;
-#ifdef CONFIG_ION_CMA_HEAP
-	case ION_HEAP_TYPE_DMA:
-		ion_cma_heap_destroy(heap);
-		break;
-#endif
-	default:
-		pr_err("%s: Invalid heap type %d\n", __func__,
-		       heap->type);
-	}
-}
-EXPORT_SYMBOL(ion_heap_destroy);

drivers/staging/android/ion/ion_system_heap.c

···
 	return -ENOMEM;
 }
 
-struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused)
+static struct ion_heap *__ion_system_heap_create(void)
 {
 	struct ion_system_heap *heap;
 
···
 	return ERR_PTR(-ENOMEM);
 }
 
-void ion_system_heap_destroy(struct ion_heap *heap)
+static int ion_system_heap_create(void)
 {
-	struct ion_system_heap *sys_heap = container_of(heap,
-							struct ion_system_heap,
-							heap);
-	int i;
+	struct ion_heap *heap;
 
-	for (i = 0; i < NUM_ORDERS; i++) {
-		ion_page_pool_destroy(sys_heap->uncached_pools[i]);
-		ion_page_pool_destroy(sys_heap->cached_pools[i]);
-	}
-	kfree(sys_heap);
+	heap = __ion_system_heap_create();
+	if (IS_ERR(heap))
+		return PTR_ERR(heap);
+	heap->name = "ion_system_heap";
+
+	ion_device_add_heap(heap);
+	return 0;
 }
+device_initcall(ion_system_heap_create);
 
 static int ion_system_contig_heap_allocate(struct ion_heap *heap,
 					   struct ion_buffer *buffer,
···
 	.map_user = ion_heap_map_user,
 };
 
-struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *unused)
+static struct ion_heap *__ion_system_contig_heap_create(void)
 {
 	struct ion_heap *heap;
 
···
 		return ERR_PTR(-ENOMEM);
 	heap->ops = &kmalloc_ops;
 	heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
+	heap->name = "ion_system_contig_heap";
 	return heap;
 }
 
-void ion_system_contig_heap_destroy(struct ion_heap *heap)
+static int ion_system_contig_heap_create(void)
 {
-	kfree(heap);
+	struct ion_heap *heap;
+
+	heap = __ion_system_contig_heap_create();
+	if (IS_ERR(heap))
+		return PTR_ERR(heap);
+
+	ion_device_add_heap(heap);
+	return 0;
 }
+device_initcall(ion_system_contig_heap_create);
+