[4/4] ion: Add chunk heap

diff --git a/drivers/gpu/ion/Makefile b/drivers/gpu/ion/Makefile
index dc788e1..5634084 100644
--- a/drivers/gpu/ion/Makefile
+++ b/drivers/gpu/ion/Makefile
@@ -1,2 +1,2 @@ 
 obj-$(CONFIG_ION) +=	ion.o ion_heap.o ion_page_pool.o ion_system_heap.o \
-				ion_carveout_heap.o
+				ion_carveout_heap.o ion_chunk_heap.o
diff --git a/drivers/gpu/ion/ion_chunk_heap.c b/drivers/gpu/ion/ion_chunk_heap.c
new file mode 100644
index 0000000..22313c0
--- /dev/null
+++ b/drivers/gpu/ion/ion_chunk_heap.c
@@ -0,0 +1,207 @@ 
+/*
+ * drivers/gpu/ion/ion_chunk_heap.c
+ *
+ * Copyright (C) 2012 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/genalloc.h>
+#include <linux/io.h>
+#include <linux/ion.h>
+#include <linux/mm.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include "ion_priv.h"
+
+/* #include <asm/mach/map.h> */
+
+struct ion_chunk_heap {
+	struct ion_heap heap;
+	struct gen_pool *pool;
+	ion_phys_addr_t base;
+	unsigned long chunk_size;
+	unsigned long size;
+	unsigned long allocated;
+};
+
+static int ion_chunk_heap_allocate(struct ion_heap *heap,
+				      struct ion_buffer *buffer,
+				      unsigned long size, unsigned long align,
+				      unsigned long flags)
+{
+	struct ion_chunk_heap *chunk_heap =
+		container_of(heap, struct ion_chunk_heap, heap);
+	struct sg_table *table;
+	struct scatterlist *sg;
+	int ret, i;
+	unsigned long num_chunks;
+
+	if (ion_buffer_fault_user_mappings(buffer))
+		return -ENOMEM;
+
+	num_chunks = ALIGN(size, chunk_heap->chunk_size) /
+		chunk_heap->chunk_size;
+	buffer->size = num_chunks * chunk_heap->chunk_size;
+
+	if (buffer->size > chunk_heap->size - chunk_heap->allocated)
+		return -ENOMEM;
+
+	table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
+	if (!table)
+		return -ENOMEM;
+	ret = sg_alloc_table(table, num_chunks, GFP_KERNEL);
+	if (ret) {
+		kfree(table);
+		return ret;
+	}
+
+	sg = table->sgl;
+	for (i = 0; i < num_chunks; i++) {
+		unsigned long paddr = gen_pool_alloc(chunk_heap->pool,
+						     chunk_heap->chunk_size);
+		if (!paddr)
+			goto err;
+		sg_set_page(sg, phys_to_page(paddr), chunk_heap->chunk_size, 0);
+		sg = sg_next(sg);
+	}
+
+	buffer->priv_virt = table;
+	chunk_heap->allocated += buffer->size;
+	return 0;
+err:
+	sg = table->sgl;
+	for (i -= 1; i >= 0; i--) {
+		gen_pool_free(chunk_heap->pool, page_to_phys(sg_page(sg)),
+			      sg_dma_len(sg));
+		sg = sg_next(sg);
+	}
+	sg_free_table(table);
+	kfree(table);
+	return -ENOMEM;
+}
+
+static void ion_chunk_heap_free(struct ion_buffer *buffer)
+{
+	struct ion_heap *heap = buffer->heap;
+	struct ion_chunk_heap *chunk_heap =
+		container_of(heap, struct ion_chunk_heap, heap);
+	struct sg_table *table = buffer->priv_virt;
+	struct scatterlist *sg;
+	int i;
+
+	ion_heap_buffer_zero(buffer);
+
+	for_each_sg(table->sgl, sg, table->nents, i) {
+		if (ion_buffer_cached(buffer))
+			dma_sync_single_for_device(NULL,
+				pfn_to_dma(NULL, page_to_pfn(sg_page(sg))),
+				sg_dma_len(sg), DMA_BIDIRECTIONAL);
+		gen_pool_free(chunk_heap->pool, page_to_phys(sg_page(sg)),
+			      sg_dma_len(sg));
+	}
+	chunk_heap->allocated -= buffer->size;
+	sg_free_table(table);
+	kfree(table);
+}
+
+struct sg_table *ion_chunk_heap_map_dma(struct ion_heap *heap,
+					 struct ion_buffer *buffer)
+{
+	return buffer->priv_virt;
+}
+
+void ion_chunk_heap_unmap_dma(struct ion_heap *heap,
+			       struct ion_buffer *buffer)
+{
+	return;
+}
+
+static struct ion_heap_ops chunk_heap_ops = {
+	.allocate = ion_chunk_heap_allocate,
+	.free = ion_chunk_heap_free,
+	.map_dma = ion_chunk_heap_map_dma,
+	.unmap_dma = ion_chunk_heap_unmap_dma,
+	.map_user = ion_heap_map_user,
+};
+
+struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *heap_data)
+{
+	struct ion_chunk_heap *chunk_heap;
+	struct vm_struct *vm_struct;
+	pgprot_t pgprot = pgprot_writecombine(PAGE_KERNEL);
+	int i, ret;
+
+
+	chunk_heap = kzalloc(sizeof(struct ion_chunk_heap), GFP_KERNEL);
+	if (!chunk_heap)
+		return ERR_PTR(-ENOMEM);
+
+	chunk_heap->chunk_size = (unsigned long)heap_data->priv;
+	chunk_heap->pool = gen_pool_create(get_order(chunk_heap->chunk_size) +
+					   PAGE_SHIFT, -1);
+	if (!chunk_heap->pool) {
+		ret = -ENOMEM;
+		goto error_gen_pool_create;
+	}
+	chunk_heap->base = heap_data->base;
+	chunk_heap->size = heap_data->size;
+	chunk_heap->allocated = 0;
+
+	vm_struct = get_vm_area(PAGE_SIZE, VM_ALLOC);
+	if (!vm_struct) {
+		ret = -ENOMEM;
+		goto error;
+	}
+	for (i = 0; i < chunk_heap->size; i += PAGE_SIZE) {
+		struct page *page = phys_to_page(chunk_heap->base + i);
+		struct page **pages = &page;
+
+		ret = map_vm_area(vm_struct, pgprot, &pages);
+		if (ret)
+			goto error_map_vm_area;
+		memset(vm_struct->addr, 0, PAGE_SIZE);
+		unmap_kernel_range((unsigned long)vm_struct->addr, PAGE_SIZE);
+	}
+	free_vm_area(vm_struct);
+
+	dma_sync_single_for_device(NULL,
+		pfn_to_dma(NULL, page_to_pfn(phys_to_page(heap_data->base))),
+		heap_data->size, DMA_BIDIRECTIONAL);
+	gen_pool_add(chunk_heap->pool, chunk_heap->base, heap_data->size, -1);
+	chunk_heap->heap.ops = &chunk_heap_ops;
+	chunk_heap->heap.type = ION_HEAP_TYPE_CHUNK;
+	chunk_heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
+	pr_info("%s: base %lu size %lu align %ld\n", __func__, chunk_heap->base,
+		heap_data->size, heap_data->align);
+
+	return &chunk_heap->heap;
+
+error_map_vm_area:
+	free_vm_area(vm_struct);
+error:
+	gen_pool_destroy(chunk_heap->pool);
+error_gen_pool_create:
+	kfree(chunk_heap);
+	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;
+}
diff --git a/drivers/gpu/ion/ion_heap.c b/drivers/gpu/ion/ion_heap.c
index 3a565fc..4692a46 100644
--- a/drivers/gpu/ion/ion_heap.c
+++ b/drivers/gpu/ion/ion_heap.c
@@ -104,6 +104,9 @@  struct ion_heap *ion_heap_create(struct ion_platform_heap *heap_data)
 	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;
 	default:
 		pr_err("%s: Invalid heap type %d\n", __func__,
 		       heap_data->type);
@@ -137,6 +140,9 @@  void ion_heap_destroy(struct ion_heap *heap)
 	case ION_HEAP_TYPE_CARVEOUT:
 		ion_carveout_heap_destroy(heap);
 		break;
+	case ION_HEAP_TYPE_CHUNK:
+		ion_chunk_heap_destroy(heap);
+		break;
 	default:
 		pr_err("%s: Invalid heap type %d\n", __func__,
 		       heap->type);
diff --git a/include/linux/ion.h b/include/linux/ion.h
index 1ef8a0d..d60745e 100644
--- a/include/linux/ion.h
+++ b/include/linux/ion.h
@@ -35,6 +35,7 @@  enum ion_heap_type {
 	ION_HEAP_TYPE_SYSTEM,
 	ION_HEAP_TYPE_SYSTEM_CONTIG,
 	ION_HEAP_TYPE_CARVEOUT,
+	ION_HEAP_TYPE_CHUNK,
 	ION_NUM_HEAPS = 16,
 };