Revert "staging: android: ion: Remove file ion_carveout_heap.c"

	  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_CMA_HEAP

	bool "Ion CMA heap support"

	depends on ION && DMA_CMA

# SPDX-License-Identifier: GPL-2.0

obj-$(CONFIG_ION) += ion.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_CMA_HEAP) += ion_cma_heap.o

// SPDX-License-Identifier: GPL-2.0

/*

 * ION Memory Allocator carveout heap helper

 *

 * Copyright (C) 2011 Google, Inc.

 */

#include <linux/dma-mapping.h>

#include <linux/err.h>

#include <linux/genalloc.h>

#include <linux/io.h>

#include <linux/mm.h>

#include <linux/scatterlist.h>

#include <linux/slab.h>

#include "ion.h"

#define ION_CARVEOUT_ALLOCATE_FAIL	-1

struct ion_carveout_heap {

	struct ion_heap heap;

	struct gen_pool *pool;

};

static phys_addr_t ion_carveout_allocate(struct ion_heap *heap,

					 unsigned long size)

{

	struct ion_carveout_heap *carveout_heap =

		container_of(heap, struct ion_carveout_heap, heap);

	unsigned long offset = gen_pool_alloc(carveout_heap->pool, size);

	if (!offset)

		return ION_CARVEOUT_ALLOCATE_FAIL;

	return offset;

}

static void ion_carveout_free(struct ion_heap *heap, phys_addr_t addr,

			      unsigned long size)

{

	struct ion_carveout_heap *carveout_heap =

		container_of(heap, struct ion_carveout_heap, heap);

	if (addr == ION_CARVEOUT_ALLOCATE_FAIL)

		return;

	gen_pool_free(carveout_heap->pool, addr, size);

}

static int ion_carveout_heap_allocate(struct ion_heap *heap,

				      struct ion_buffer *buffer,

				      unsigned long size,

				      unsigned long flags)

{

	struct sg_table *table;

	phys_addr_t paddr;

	int ret;

	table = kmalloc(sizeof(*table), GFP_KERNEL);

	if (!table)

		return -ENOMEM;

	ret = sg_alloc_table(table, 1, GFP_KERNEL);

	if (ret)

		goto err_free;

	paddr = ion_carveout_allocate(heap, size);

	if (paddr == ION_CARVEOUT_ALLOCATE_FAIL) {

		ret = -ENOMEM;

		goto err_free_table;

	}

	sg_set_page(table->sgl, pfn_to_page(PFN_DOWN(paddr)), size, 0);

	buffer->sg_table = table;

	return 0;

err_free_table:

	sg_free_table(table);

err_free:

	kfree(table);

	return ret;

}

static void ion_carveout_heap_free(struct ion_buffer *buffer)

{

	struct ion_heap *heap = buffer->heap;

	struct sg_table *table = buffer->sg_table;

	struct page *page = sg_page(table->sgl);

	phys_addr_t paddr = PFN_PHYS(page_to_pfn(page));

	ion_heap_buffer_zero(buffer);

	ion_carveout_free(heap, paddr, buffer->size);

	sg_free_table(table);

	kfree(table);

}

static struct ion_heap_ops carveout_heap_ops = {

	.allocate = ion_carveout_heap_allocate,

	.free = ion_carveout_heap_free,

	.map_user = ion_heap_map_user,

	.map_kernel = ion_heap_map_kernel,

	.unmap_kernel = ion_heap_unmap_kernel,

};

struct ion_heap *ion_carveout_heap_create(phys_addr_t base, size_t size)

{

	struct ion_carveout_heap *carveout_heap;

	int ret;

	struct page *page;

	page = pfn_to_page(PFN_DOWN(base));

	ret = ion_heap_pages_zero(page, size, pgprot_writecombine(PAGE_KERNEL));

	if (ret)

		return ERR_PTR(ret);

	carveout_heap = kzalloc(sizeof(*carveout_heap), GFP_KERNEL);

	if (!carveout_heap)

		return ERR_PTR(-ENOMEM);

	carveout_heap->pool = gen_pool_create(PAGE_SHIFT, -1);

	if (!carveout_heap->pool) {

		kfree(carveout_heap);

		return ERR_PTR(-ENOMEM);

	}

	gen_pool_add(carveout_heap->pool, base, size, -1);

	carveout_heap->heap.ops = &carveout_heap_ops;

	carveout_heap->heap.type = ION_HEAP_TYPE_CARVEOUT;

	carveout_heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;

	return &carveout_heap->heap;

}