Revert "staging: ion: remove from the tree"

This reverts commit e722a295cf.

MAINTAINERS

@@ -1239,6 +1239,16 @@ S:	Supported
 F:	Documentation/devicetree/bindings/rtc/google,goldfish-rtc.txt
 F:	drivers/rtc/rtc-goldfish.c
 
+ANDROID ION DRIVER
+M:	Laura Abbott <labbott@redhat.com>
+M:	Sumit Semwal <sumit.semwal@linaro.org>
+L:	devel@driverdev.osuosl.org
+L:	dri-devel@lists.freedesktop.org
+L:	linaro-mm-sig@lists.linaro.org (moderated for non-subscribers)
+S:	Supported
+F:	drivers/staging/android/ion
+F:	drivers/staging/android/uapi/ion.h
+
 AOA (Apple Onboard Audio) ALSA DRIVER
 M:	Johannes Berg <johannes@sipsolutions.net>
 L:	linuxppc-dev@lists.ozlabs.org

drivers/staging/android/Kconfig

@@ -25,6 +25,8 @@ config DEBUG_KINFO
 	   - UTS_RELEASE
 	   - BUILD_INFO(ro.build.fingerprint)
 
+source "drivers/staging/android/ion/Kconfig"
+
 endif # if ANDROID
 
 endmenu

drivers/staging/android/Makefile

@@ -1,5 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 ccflags-y += -I$(src)			# needed for trace events
 
+obj-y					+= ion/
+
 obj-$(CONFIG_ASHMEM)			+= ashmem.o
 obj-$(CONFIG_DEBUG_KINFO)	+= debug_kinfo.o

drivers/staging/android/TODO

@@ -4,5 +4,10 @@ TODO:
 	- add proper arch dependencies as needed
 	- audit userspace interfaces to make sure they are sane
 
+
+ion/
+ - Split /dev/ion up into multiple nodes (e.g. /dev/ion/heap0)
+ - Better test framework (integration with VGEM was suggested)
+
 Please send patches to Greg Kroah-Hartman <greg@kroah.com> and Cc:
 Arve Hjønnevåg <arve@android.com> and Riley Andrews <riandrews@android.com>

drivers/staging/android/ion/Kconfig

@@ -0,0 +1,27 @@
+# SPDX-License-Identifier: GPL-2.0
+menuconfig ION
+	bool "Ion Memory Manager"
+	depends on HAS_DMA && MMU
+	select GENERIC_ALLOCATOR
+	select DMA_SHARED_BUFFER
+	help
+	  Choose this option to enable the ION Memory Manager,
+	  used by Android to efficiently allocate buffers
+	  from userspace that can be shared between drivers.
+	  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_CMA_HEAP
+	bool "Ion CMA heap support"
+	depends on ION && DMA_CMA
+	help
+	  Choose this option to enable CMA heaps with Ion. This heap is backed
+	  by the Contiguous Memory Allocator (CMA). If your system has these
+	  regions, you should say Y here.

drivers/staging/android/ion/Makefile

@@ -0,0 +1,4 @@
+# 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_CMA_HEAP) += ion_cma_heap.o

drivers/staging/android/ion/ion.c

@@ -0,0 +1,649 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ION Memory Allocator
+ *
+ * Copyright (C) 2011 Google, Inc.
+ */
+
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/dma-buf.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/file.h>
+#include <linux/freezer.h>
+#include <linux/fs.h>
+#include <linux/kthread.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/mm_types.h>
+#include <linux/rbtree.h>
+#include <linux/sched/task.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+
+#include "ion.h"
+
+static struct ion_device *internal_dev;
+static int heap_id;
+
+/* this function should only be called while dev->lock is held */
+static struct ion_buffer *ion_buffer_create(struct ion_heap *heap,
+					    struct ion_device *dev,
+					    unsigned long len,
+					    unsigned long flags)
+{
+	struct ion_buffer *buffer;
+	int ret;
+
+	buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
+	if (!buffer)
+		return ERR_PTR(-ENOMEM);
+
+	buffer->heap = heap;
+	buffer->flags = flags;
+	buffer->dev = dev;
+	buffer->size = len;
+
+	ret = heap->ops->allocate(heap, buffer, len, flags);
+
+	if (ret) {
+		if (!(heap->flags & ION_HEAP_FLAG_DEFER_FREE))
+			goto err2;
+
+		ion_heap_freelist_drain(heap, 0);
+		ret = heap->ops->allocate(heap, buffer, len, flags);
+		if (ret)
+			goto err2;
+	}
+
+	if (!buffer->sg_table) {
+		WARN_ONCE(1, "This heap needs to set the sgtable");
+		ret = -EINVAL;
+		goto err1;
+	}
+
+	spin_lock(&heap->stat_lock);
+	heap->num_of_buffers++;
+	heap->num_of_alloc_bytes += len;
+	if (heap->num_of_alloc_bytes > heap->alloc_bytes_wm)
+		heap->alloc_bytes_wm = heap->num_of_alloc_bytes;
+	spin_unlock(&heap->stat_lock);
+
+	INIT_LIST_HEAD(&buffer->attachments);
+	mutex_init(&buffer->lock);
+	return buffer;
+
+err1:
+	heap->ops->free(buffer);
+err2:
+	kfree(buffer);
+	return ERR_PTR(ret);
+}
+
+void ion_buffer_destroy(struct ion_buffer *buffer)
+{
+	if (buffer->kmap_cnt > 0) {
+		pr_warn_once("%s: buffer still mapped in the kernel\n",
+			     __func__);
+		buffer->heap->ops->unmap_kernel(buffer->heap, buffer);
+	}
+	buffer->heap->ops->free(buffer);
+	spin_lock(&buffer->heap->stat_lock);
+	buffer->heap->num_of_buffers--;
+	buffer->heap->num_of_alloc_bytes -= buffer->size;
+	spin_unlock(&buffer->heap->stat_lock);
+
+	kfree(buffer);
+}
+
+static void _ion_buffer_destroy(struct ion_buffer *buffer)
+{
+	struct ion_heap *heap = buffer->heap;
+
+	if (heap->flags & ION_HEAP_FLAG_DEFER_FREE)
+		ion_heap_freelist_add(heap, buffer);
+	else
+		ion_buffer_destroy(buffer);
+}
+
+static void *ion_buffer_kmap_get(struct ion_buffer *buffer)
+{
+	void *vaddr;
+
+	if (buffer->kmap_cnt) {
+		buffer->kmap_cnt++;
+		return buffer->vaddr;
+	}
+	vaddr = buffer->heap->ops->map_kernel(buffer->heap, buffer);
+	if (WARN_ONCE(!vaddr,
+		      "heap->ops->map_kernel should return ERR_PTR on error"))
+		return ERR_PTR(-EINVAL);
+	if (IS_ERR(vaddr))
+		return vaddr;
+	buffer->vaddr = vaddr;
+	buffer->kmap_cnt++;
+	return vaddr;
+}
+
+static void ion_buffer_kmap_put(struct ion_buffer *buffer)
+{
+	buffer->kmap_cnt--;
+	if (!buffer->kmap_cnt) {
+		buffer->heap->ops->unmap_kernel(buffer->heap, buffer);
+		buffer->vaddr = NULL;
+	}
+}
+
+static struct sg_table *dup_sg_table(struct sg_table *table)
+{
+	struct sg_table *new_table;
+	int ret, i;
+	struct scatterlist *sg, *new_sg;
+
+	new_table = kzalloc(sizeof(*new_table), GFP_KERNEL);
+	if (!new_table)
+		return ERR_PTR(-ENOMEM);
+
+	ret = sg_alloc_table(new_table, table->orig_nents, GFP_KERNEL);
+	if (ret) {
+		kfree(new_table);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	new_sg = new_table->sgl;
+	for_each_sgtable_sg(table, sg, i) {
+		memcpy(new_sg, sg, sizeof(*sg));
+		new_sg->dma_address = 0;
+		new_sg = sg_next(new_sg);
+	}
+
+	return new_table;
+}
+
+static void free_duped_table(struct sg_table *table)
+{
+	sg_free_table(table);
+	kfree(table);
+}
+
+struct ion_dma_buf_attachment {
+	struct device *dev;
+	struct sg_table *table;
+	struct list_head list;
+};
+
+static int ion_dma_buf_attach(struct dma_buf *dmabuf,
+			      struct dma_buf_attachment *attachment)
+{
+	struct ion_dma_buf_attachment *a;
+	struct sg_table *table;
+	struct ion_buffer *buffer = dmabuf->priv;
+
+	a = kzalloc(sizeof(*a), GFP_KERNEL);
+	if (!a)
+		return -ENOMEM;
+
+	table = dup_sg_table(buffer->sg_table);
+	if (IS_ERR(table)) {
+		kfree(a);
+		return -ENOMEM;
+	}
+
+	a->table = table;
+	a->dev = attachment->dev;
+	INIT_LIST_HEAD(&a->list);
+
+	attachment->priv = a;
+
+	mutex_lock(&buffer->lock);
+	list_add(&a->list, &buffer->attachments);
+	mutex_unlock(&buffer->lock);
+
+	return 0;
+}
+
+static void ion_dma_buf_detach(struct dma_buf *dmabuf,
+			       struct dma_buf_attachment *attachment)
+{
+	struct ion_dma_buf_attachment *a = attachment->priv;
+	struct ion_buffer *buffer = dmabuf->priv;
+
+	mutex_lock(&buffer->lock);
+	list_del(&a->list);
+	mutex_unlock(&buffer->lock);
+	free_duped_table(a->table);
+
+	kfree(a);
+}
+
+static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment,
+					enum dma_data_direction direction)
+{
+	struct ion_dma_buf_attachment *a = attachment->priv;
+	struct sg_table *table;
+	int ret;
+
+	table = a->table;
+
+	ret = dma_map_sgtable(attachment->dev, table, direction, 0);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return table;
+}
+
+static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment,
+			      struct sg_table *table,
+			      enum dma_data_direction direction)
+{
+	dma_unmap_sgtable(attachment->dev, table, direction, 0);
+}
+
+static int ion_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
+{
+	struct ion_buffer *buffer = dmabuf->priv;
+	int ret = 0;
+
+	if (!buffer->heap->ops->map_user) {
+		pr_err("%s: this heap does not define a method for mapping to userspace\n",
+		       __func__);
+		return -EINVAL;
+	}
+
+	if (!(buffer->flags & ION_FLAG_CACHED))
+		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
+
+	mutex_lock(&buffer->lock);
+	/* now map it to userspace */
+	ret = buffer->heap->ops->map_user(buffer->heap, buffer, vma);
+	mutex_unlock(&buffer->lock);
+
+	if (ret)
+		pr_err("%s: failure mapping buffer to userspace\n",
+		       __func__);
+
+	return ret;
+}
+
+static void ion_dma_buf_release(struct dma_buf *dmabuf)
+{
+	struct ion_buffer *buffer = dmabuf->priv;
+
+	_ion_buffer_destroy(buffer);
+}
+
+static int ion_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
+					enum dma_data_direction direction)
+{
+	struct ion_buffer *buffer = dmabuf->priv;
+	void *vaddr;
+	struct ion_dma_buf_attachment *a;
+	int ret = 0;
+
+	/*
+	 * TODO: Move this elsewhere because we don't always need a vaddr
+	 */
+	if (buffer->heap->ops->map_kernel) {
+		mutex_lock(&buffer->lock);
+		vaddr = ion_buffer_kmap_get(buffer);
+		if (IS_ERR(vaddr)) {
+			ret = PTR_ERR(vaddr);
+			goto unlock;
+		}
+		mutex_unlock(&buffer->lock);
+	}
+
+	mutex_lock(&buffer->lock);
+	list_for_each_entry(a, &buffer->attachments, list)
+		dma_sync_sgtable_for_cpu(a->dev, a->table, direction);
+
+unlock:
+	mutex_unlock(&buffer->lock);
+	return ret;
+}
+
+static int ion_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
+				      enum dma_data_direction direction)
+{
+	struct ion_buffer *buffer = dmabuf->priv;
+	struct ion_dma_buf_attachment *a;
+
+	if (buffer->heap->ops->map_kernel) {
+		mutex_lock(&buffer->lock);
+		ion_buffer_kmap_put(buffer);
+		mutex_unlock(&buffer->lock);
+	}
+
+	mutex_lock(&buffer->lock);
+	list_for_each_entry(a, &buffer->attachments, list)
+		dma_sync_sgtable_for_device(a->dev, a->table, direction);
+	mutex_unlock(&buffer->lock);
+
+	return 0;
+}
+
+static const struct dma_buf_ops dma_buf_ops = {
+	.map_dma_buf = ion_map_dma_buf,
+	.unmap_dma_buf = ion_unmap_dma_buf,
+	.mmap = ion_mmap,
+	.release = ion_dma_buf_release,
+	.attach = ion_dma_buf_attach,
+	.detach = ion_dma_buf_detach,
+	.begin_cpu_access = ion_dma_buf_begin_cpu_access,
+	.end_cpu_access = ion_dma_buf_end_cpu_access,
+};
+
+static int ion_alloc(size_t len, unsigned int heap_id_mask, unsigned int flags)
+{
+	struct ion_device *dev = internal_dev;
+	struct ion_buffer *buffer = NULL;
+	struct ion_heap *heap;
+	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+	int fd;
+	struct dma_buf *dmabuf;
+
+	pr_debug("%s: len %zu heap_id_mask %u flags %x\n", __func__,
+		 len, heap_id_mask, flags);
+	/*
+	 * traverse the list of heaps available in this system in priority
+	 * order.  If the heap type is supported by the client, and matches the
+	 * request of the caller allocate from it.  Repeat until allocate has
+	 * succeeded or all heaps have been tried
+	 */
+	len = PAGE_ALIGN(len);
+
+	if (!len)
+		return -EINVAL;
+
+	down_read(&dev->lock);
+	plist_for_each_entry(heap, &dev->heaps, node) {
+		/* if the caller didn't specify this heap id */
+		if (!((1 << heap->id) & heap_id_mask))
+			continue;
+		buffer = ion_buffer_create(heap, dev, len, flags);
+		if (!IS_ERR(buffer))
+			break;
+	}
+	up_read(&dev->lock);
+
+	if (!buffer)
+		return -ENODEV;
+
+	if (IS_ERR(buffer))
+		return PTR_ERR(buffer);
+
+	exp_info.ops = &dma_buf_ops;
+	exp_info.size = buffer->size;
+	exp_info.flags = O_RDWR;
+	exp_info.priv = buffer;
+
+	dmabuf = dma_buf_export(&exp_info);
+	if (IS_ERR(dmabuf)) {
+		_ion_buffer_destroy(buffer);
+		return PTR_ERR(dmabuf);
+	}
+
+	fd = dma_buf_fd(dmabuf, O_CLOEXEC);
+	if (fd < 0)
+		dma_buf_put(dmabuf);
+
+	return fd;
+}
+
+static int ion_query_heaps(struct ion_heap_query *query)
+{
+	struct ion_device *dev = internal_dev;
+	struct ion_heap_data __user *buffer = u64_to_user_ptr(query->heaps);
+	int ret = -EINVAL, cnt = 0, max_cnt;
+	struct ion_heap *heap;
+	struct ion_heap_data hdata;
+
+	memset(&hdata, 0, sizeof(hdata));
+
+	down_read(&dev->lock);
+	if (!buffer) {
+		query->cnt = dev->heap_cnt;
+		ret = 0;
+		goto out;
+	}
+
+	if (query->cnt <= 0)
+		goto out;
+
+	max_cnt = query->cnt;
+
+	plist_for_each_entry(heap, &dev->heaps, node) {
+		strncpy(hdata.name, heap->name, MAX_HEAP_NAME);
+		hdata.name[sizeof(hdata.name) - 1] = '\0';
+		hdata.type = heap->type;
+		hdata.heap_id = heap->id;
+
+		if (copy_to_user(&buffer[cnt], &hdata, sizeof(hdata))) {
+			ret = -EFAULT;
+			goto out;
+		}
+
+		cnt++;
+		if (cnt >= max_cnt)
+			break;
+	}
+
+	query->cnt = cnt;
+	ret = 0;
+out:
+	up_read(&dev->lock);
+	return ret;
+}
+
+union ion_ioctl_arg {
+	struct ion_allocation_data allocation;
+	struct ion_heap_query query;
+};
+
+static int validate_ioctl_arg(unsigned int cmd, union ion_ioctl_arg *arg)
+{
+	switch (cmd) {
+	case ION_IOC_HEAP_QUERY:
+		if (arg->query.reserved0 ||
+		    arg->query.reserved1 ||
+		    arg->query.reserved2)
+			return -EINVAL;
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static long ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	int ret = 0;
+	union ion_ioctl_arg data;
+
+	if (_IOC_SIZE(cmd) > sizeof(data))
+		return -EINVAL;
+
+	/*
+	 * The copy_from_user is unconditional here for both read and write
+	 * to do the validate. If there is no write for the ioctl, the
+	 * buffer is cleared
+	 */
+	if (copy_from_user(&data, (void __user *)arg, _IOC_SIZE(cmd)))
+		return -EFAULT;
+
+	ret = validate_ioctl_arg(cmd, &data);
+	if (ret) {
+		pr_warn_once("%s: ioctl validate failed\n", __func__);
+		return ret;
+	}
+
+	if (!(_IOC_DIR(cmd) & _IOC_WRITE))
+		memset(&data, 0, sizeof(data));
+
+	switch (cmd) {
+	case ION_IOC_ALLOC:
+	{
+		int fd;
+
+		fd = ion_alloc(data.allocation.len,
+			       data.allocation.heap_id_mask,
+			       data.allocation.flags);
+		if (fd < 0)
+			return fd;
+
+		data.allocation.fd = fd;
+
+		break;
+	}
+	case ION_IOC_HEAP_QUERY:
+		ret = ion_query_heaps(&data.query);
+		break;
+	default:
+		return -ENOTTY;
+	}
+
+	if (_IOC_DIR(cmd) & _IOC_READ) {
+		if (copy_to_user((void __user *)arg, &data, _IOC_SIZE(cmd)))
+			return -EFAULT;
+	}
+	return ret;
+}
+
+static const struct file_operations ion_fops = {
+	.owner          = THIS_MODULE,
+	.unlocked_ioctl = ion_ioctl,
+	.compat_ioctl	= compat_ptr_ioctl,
+};
+
+static int debug_shrink_set(void *data, u64 val)
+{
+	struct ion_heap *heap = data;
+	struct shrink_control sc;
+	int objs;
+
+	sc.gfp_mask = GFP_HIGHUSER;
+	sc.nr_to_scan = val;
+
+	if (!val) {
+		objs = heap->shrinker.count_objects(&heap->shrinker, &sc);
+		sc.nr_to_scan = objs;
+	}
+
+	heap->shrinker.scan_objects(&heap->shrinker, &sc);
+	return 0;
+}
+
+static int debug_shrink_get(void *data, u64 *val)
+{
+	struct ion_heap *heap = data;
+	struct shrink_control sc;
+	int objs;
+
+	sc.gfp_mask = GFP_HIGHUSER;
+	sc.nr_to_scan = 0;
+
+	objs = heap->shrinker.count_objects(&heap->shrinker, &sc);
+	*val = objs;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(debug_shrink_fops, debug_shrink_get,
+			debug_shrink_set, "%llu\n");
+
+void ion_device_add_heap(struct ion_heap *heap)
+{
+	struct ion_device *dev = internal_dev;
+	int ret;
+	struct dentry *heap_root;
+	char debug_name[64];
+
+	if (!heap->ops->allocate || !heap->ops->free)
+		pr_err("%s: can not add heap with invalid ops struct.\n",
+		       __func__);
+
+	spin_lock_init(&heap->free_lock);
+	spin_lock_init(&heap->stat_lock);
+	heap->free_list_size = 0;
+
+	if (heap->flags & ION_HEAP_FLAG_DEFER_FREE)
+		ion_heap_init_deferred_free(heap);
+
+	if ((heap->flags & ION_HEAP_FLAG_DEFER_FREE) || heap->ops->shrink) {
+		ret = ion_heap_init_shrinker(heap);
+		if (ret)
+			pr_err("%s: Failed to register shrinker\n", __func__);
+	}
+
+	heap->dev = dev;
+	heap->num_of_buffers = 0;
+	heap->num_of_alloc_bytes = 0;
+	heap->alloc_bytes_wm = 0;
+
+	heap_root = debugfs_create_dir(heap->name, dev->debug_root);
+	debugfs_create_u64("num_of_buffers",
+			   0444, heap_root,
+			   &heap->num_of_buffers);
+	debugfs_create_u64("num_of_alloc_bytes",
+			   0444,
+			   heap_root,
+			   &heap->num_of_alloc_bytes);
+	debugfs_create_u64("alloc_bytes_wm",
+			   0444,
+			   heap_root,
+			   &heap->alloc_bytes_wm);
+
+	if (heap->shrinker.count_objects &&
+	    heap->shrinker.scan_objects) {
+		snprintf(debug_name, 64, "%s_shrink", heap->name);
+		debugfs_create_file(debug_name,
+				    0644,
+				    heap_root,
+				    heap,
+				    &debug_shrink_fops);
+	}
+
+	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
+	 */
+	plist_node_init(&heap->node, -heap->id);
+	plist_add(&heap->node, &dev->heaps);
+
+	dev->heap_cnt++;
+	up_write(&dev->lock);
+}
+EXPORT_SYMBOL(ion_device_add_heap);
+
+static int ion_device_create(void)
+{
+	struct ion_device *idev;
+	int ret;
+
+	idev = kzalloc(sizeof(*idev), GFP_KERNEL);
+	if (!idev)
+		return -ENOMEM;
+
+	idev->dev.minor = MISC_DYNAMIC_MINOR;
+	idev->dev.name = "ion";
+	idev->dev.fops = &ion_fops;
+	idev->dev.parent = NULL;
+	ret = misc_register(&idev->dev);
+	if (ret) {
+		pr_err("ion: failed to register misc device.\n");
+		kfree(idev);
+		return ret;
+	}
+
+	idev->debug_root = debugfs_create_dir("ion", NULL);
+	init_rwsem(&idev->lock);
+	plist_head_init(&idev->heaps);
+	internal_dev = idev;
+	return 0;
+}
+subsys_initcall(ion_device_create);

drivers/staging/android/ion/ion.h

@@ -0,0 +1,302 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ION Memory Allocator kernel interface header
+ *
+ * Copyright (C) 2011 Google, Inc.
+ */
+
+#ifndef _ION_H
+#define _ION_H
+
+#include <linux/device.h>
+#include <linux/dma-direction.h>
+#include <linux/kref.h>
+#include <linux/mm_types.h>
+#include <linux/mutex.h>
+#include <linux/rbtree.h>
+#include <linux/sched.h>
+#include <linux/shrinker.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+
+#include "../uapi/ion.h"
+
+/**
+ * struct ion_buffer - metadata for a particular buffer
+ * @list:		element in list of deferred freeable buffers
+ * @dev:		back pointer to the ion_device
+ * @heap:		back pointer to the heap the buffer came from
+ * @flags:		buffer specific flags
+ * @private_flags:	internal buffer specific flags
+ * @size:		size of the buffer
+ * @priv_virt:		private data to the buffer representable as
+ *			a void *
+ * @lock:		protects the buffers cnt fields
+ * @kmap_cnt:		number of times the buffer is mapped to the kernel
+ * @vaddr:		the kernel mapping if kmap_cnt is not zero
+ * @sg_table:		the sg table for the buffer
+ * @attachments:	list of devices attached to this buffer
+ */
+struct ion_buffer {
+	struct list_head list;
+	struct ion_device *dev;
+	struct ion_heap *heap;
+	unsigned long flags;
+	unsigned long private_flags;
+	size_t size;
+	void *priv_virt;
+	struct mutex lock;
+	int kmap_cnt;
+	void *vaddr;
+	struct sg_table *sg_table;
+	struct list_head attachments;
+};
+
+void ion_buffer_destroy(struct ion_buffer *buffer);
+
+/**
+ * struct ion_device - the metadata of the ion device node
+ * @dev:		the actual misc device
+ * @lock:		rwsem protecting the tree of heaps and clients
+ */
+struct ion_device {
+	struct miscdevice dev;
+	struct rw_semaphore lock;
+	struct plist_head heaps;
+	struct dentry *debug_root;
+	int heap_cnt;
+};
+
+/**
+ * struct ion_heap_ops - ops to operate on a given heap
+ * @allocate:		allocate memory
+ * @free:		free memory
+ * @map_kernel		map memory to the kernel
+ * @unmap_kernel	unmap memory to the kernel
+ * @map_user		map memory to userspace
+ *
+ * allocate, phys, and map_user return 0 on success, -errno on error.
+ * map_dma and map_kernel return pointer on success, ERR_PTR on
+ * error. @free will be called with ION_PRIV_FLAG_SHRINKER_FREE set in
+ * the buffer's private_flags when called from a shrinker. In that
+ * case, the pages being free'd must be truly free'd back to the
+ * system, not put in a page pool or otherwise cached.
+ */
+struct ion_heap_ops {
+	int (*allocate)(struct ion_heap *heap,
+			struct ion_buffer *buffer, unsigned long len,
+			unsigned long flags);
+	void (*free)(struct ion_buffer *buffer);
+	void * (*map_kernel)(struct ion_heap *heap, struct ion_buffer *buffer);
+	void (*unmap_kernel)(struct ion_heap *heap, struct ion_buffer *buffer);
+	int (*map_user)(struct ion_heap *mapper, struct ion_buffer *buffer,
+			struct vm_area_struct *vma);
+	int (*shrink)(struct ion_heap *heap, gfp_t gfp_mask, int nr_to_scan);
+};
+
+/**
+ * heap flags - flags between the heaps and core ion code
+ */
+#define ION_HEAP_FLAG_DEFER_FREE BIT(0)
+
+/**
+ * private flags - flags internal to ion
+ */
+/*
+ * Buffer is being freed from a shrinker function. Skip any possible
+ * heap-specific caching mechanism (e.g. page pools). Guarantees that
+ * any buffer storage that came from the system allocator will be
+ * returned to the system allocator.
+ */
+#define ION_PRIV_FLAG_SHRINKER_FREE BIT(0)
+
+/**
+ * struct ion_heap - represents a heap in the system
+ * @node:		rb node to put the heap on the device's tree of heaps
+ * @dev:		back pointer to the ion_device
+ * @type:		type of heap
+ * @ops:		ops struct as above
+ * @flags:		flags
+ * @id:			id of heap, also indicates priority of this heap when
+ *			allocating.  These are specified by platform data and
+ *			MUST be unique
+ * @name:		used for debugging
+ * @shrinker:		a shrinker for the heap
+ * @free_list:		free list head if deferred free is used
+ * @free_list_size	size of the deferred free list in bytes
+ * @lock:		protects the free list
+ * @waitqueue:		queue to wait on from deferred free thread
+ * @task:		task struct of deferred free thread
+ * @num_of_buffers	the number of currently allocated buffers
+ * @num_of_alloc_bytes	the number of allocated bytes
+ * @alloc_bytes_wm	the number of allocated bytes watermark
+ *
+ * Represents a pool of memory from which buffers can be made.  In some
+ * systems the only heap is regular system memory allocated via vmalloc.
+ * On others, some blocks might require large physically contiguous buffers
+ * that are allocated from a specially reserved heap.
+ */
+struct ion_heap {
+	struct plist_node node;
+	struct ion_device *dev;
+	enum ion_heap_type type;
+	struct ion_heap_ops *ops;
+	unsigned long flags;
+	unsigned int id;
+	const char *name;
+
+	/* deferred free support */
+	struct shrinker shrinker;
+	struct list_head free_list;
+	size_t free_list_size;
+	spinlock_t free_lock;
+	wait_queue_head_t waitqueue;
+	struct task_struct *task;
+
+	/* heap statistics */
+	u64 num_of_buffers;
+	u64 num_of_alloc_bytes;
+	u64 alloc_bytes_wm;
+
+	/* protect heap statistics */
+	spinlock_t stat_lock;
+};
+
+/**
+ * ion_device_add_heap - adds a heap to the ion device
+ * @heap:		the heap to add
+ */
+void ion_device_add_heap(struct ion_heap *heap);
+
+/**
+ * some helpers for common operations on buffers using the sg_table
+ * and vaddr fields
+ */
+void *ion_heap_map_kernel(struct ion_heap *heap, struct ion_buffer *buffer);
+void ion_heap_unmap_kernel(struct ion_heap *heap, struct ion_buffer *buffer);
+int ion_heap_map_user(struct ion_heap *heap, struct ion_buffer *buffer,
+		      struct vm_area_struct *vma);
+int ion_heap_buffer_zero(struct ion_buffer *buffer);
+
+/**
+ * ion_heap_init_shrinker
+ * @heap:		the heap
+ *
+ * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag or defines the shrink op
+ * this function will be called to setup a shrinker to shrink the freelists
+ * and call the heap's shrink op.
+ */
+int ion_heap_init_shrinker(struct ion_heap *heap);
+
+/**
+ * ion_heap_init_deferred_free -- initialize deferred free functionality
+ * @heap:		the heap
+ *
+ * If a heap sets the ION_HEAP_FLAG_DEFER_FREE flag this function will
+ * be called to setup deferred frees. Calls to free the buffer will
+ * return immediately and the actual free will occur some time later
+ */
+int ion_heap_init_deferred_free(struct ion_heap *heap);
+
+/**
+ * ion_heap_freelist_add - add a buffer to the deferred free list
+ * @heap:		the heap
+ * @buffer:		the buffer
+ *
+ * Adds an item to the deferred freelist.
+ */
+void ion_heap_freelist_add(struct ion_heap *heap, struct ion_buffer *buffer);
+
+/**
+ * ion_heap_freelist_drain - drain the deferred free list
+ * @heap:		the heap
+ * @size:		amount of memory to drain in bytes
+ *
+ * Drains the indicated amount of memory from the deferred freelist immediately.
+ * Returns the total amount freed.  The total freed may be higher depending
+ * on the size of the items in the list, or lower if there is insufficient
+ * total memory on the freelist.
+ */
+size_t ion_heap_freelist_drain(struct ion_heap *heap, size_t size);
+
+/**
+ * ion_heap_freelist_shrink - drain the deferred free
+ *				list, skipping any heap-specific
+ *				pooling or caching mechanisms
+ *
+ * @heap:		the heap
+ * @size:		amount of memory to drain in bytes
+ *
+ * Drains the indicated amount of memory from the deferred freelist immediately.
+ * Returns the total amount freed.  The total freed may be higher depending
+ * on the size of the items in the list, or lower if there is insufficient
+ * total memory on the freelist.
+ *
+ * Unlike with @ion_heap_freelist_drain, don't put any pages back into
+ * page pools or otherwise cache the pages. Everything must be
+ * genuinely free'd back to the system. If you're free'ing from a
+ * shrinker you probably want to use this. Note that this relies on
+ * the heap.ops.free callback honoring the ION_PRIV_FLAG_SHRINKER_FREE
+ * flag.
+ */
+size_t ion_heap_freelist_shrink(struct ion_heap *heap,
+				size_t size);
+
+/**
+ * ion_heap_freelist_size - returns the size of the freelist in bytes
+ * @heap:		the heap
+ */
+size_t ion_heap_freelist_size(struct ion_heap *heap);
+
+/**
+ * functions for creating and destroying a heap pool -- allows you
+ * to keep a pool of pre allocated memory to use from your heap.  Keeping
+ * a pool of memory that is ready for dma, ie any cached mapping have been
+ * invalidated from the cache, provides a significant performance benefit on
+ * many systems
+ */
+
+/**
+ * struct ion_page_pool - pagepool struct
+ * @high_count:		number of highmem items in the pool
+ * @low_count:		number of lowmem items in the pool
+ * @high_items:		list of highmem items
+ * @low_items:		list of lowmem items
+ * @mutex:		lock protecting this struct and especially the count
+ *			item list
+ * @gfp_mask:		gfp_mask to use from alloc
+ * @order:		order of pages in the pool
+ * @list:		plist node for list of pools
+ *
+ * Allows you to keep a pool of pre allocated pages to use from your heap.
+ * Keeping a pool of pages that is ready for dma, ie any cached mapping have
+ * been invalidated from the cache, provides a significant performance benefit
+ * on many systems
+ */
+struct ion_page_pool {
+	int high_count;
+	int low_count;
+	struct list_head high_items;
+	struct list_head low_items;
+	struct mutex mutex;
+	gfp_t gfp_mask;
+	unsigned int order;
+	struct plist_node list;
+};
+
+struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order);
+void ion_page_pool_destroy(struct ion_page_pool *pool);
+struct page *ion_page_pool_alloc(struct ion_page_pool *pool);
+void ion_page_pool_free(struct ion_page_pool *pool, struct page *page);
+
+/** ion_page_pool_shrink - shrinks the size of the memory cached in the pool
+ * @pool:		the pool
+ * @gfp_mask:		the memory type to reclaim
+ * @nr_to_scan:		number of items to shrink in pages
+ *
+ * returns the number of items freed in pages
+ */
+int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
+			 int nr_to_scan);
+
+#endif /* _ION_H */

drivers/staging/android/ion/ion_cma_heap.c

@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ION Memory Allocator CMA heap exporter
+ *
+ * Copyright (C) Linaro 2012
+ * Author: <benjamin.gaignard@linaro.org> for ST-Ericsson.
+ */
+
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/cma.h>
+#include <linux/scatterlist.h>
+#include <linux/highmem.h>
+
+#include "ion.h"
+
+struct ion_cma_heap {
+	struct ion_heap heap;
+	struct cma *cma;
+};
+
+#define to_cma_heap(x) container_of(x, struct ion_cma_heap, heap)
+
+/* ION CMA heap operations functions */
+static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer,
+			    unsigned long len,
+			    unsigned long flags)
+{
+	struct ion_cma_heap *cma_heap = to_cma_heap(heap);
+	struct sg_table *table;
+	struct page *pages;
+	unsigned long size = PAGE_ALIGN(len);
+	unsigned long nr_pages = size >> PAGE_SHIFT;
+	unsigned long align = get_order(size);
+	int ret;
+
+	if (align > CONFIG_CMA_ALIGNMENT)
+		align = CONFIG_CMA_ALIGNMENT;
+
+	pages = cma_alloc(cma_heap->cma, nr_pages, align, false);
+	if (!pages)
+		return -ENOMEM;
+
+	if (PageHighMem(pages)) {
+		unsigned long nr_clear_pages = nr_pages;
+		struct page *page = pages;
+
+		while (nr_clear_pages > 0) {
+			void *vaddr = kmap_atomic(page);
+
+			memset(vaddr, 0, PAGE_SIZE);
+			kunmap_atomic(vaddr);
+			page++;
+			nr_clear_pages--;
+		}
+	} else {
+		memset(page_address(pages), 0, size);
+	}
+
+	table = kmalloc(sizeof(*table), GFP_KERNEL);
+	if (!table)
+		goto err;
+
+	ret = sg_alloc_table(table, 1, GFP_KERNEL);
+	if (ret)
+		goto free_mem;
+
+	sg_set_page(table->sgl, pages, size, 0);
+
+	buffer->priv_virt = pages;
+	buffer->sg_table = table;
+	return 0;
+
+free_mem:
+	kfree(table);
+err:
+	cma_release(cma_heap->cma, pages, nr_pages);
+	return -ENOMEM;
+}
+
+static void ion_cma_free(struct ion_buffer *buffer)
+{
+	struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
+	struct page *pages = buffer->priv_virt;
+	unsigned long nr_pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
+
+	/* release memory */
+	cma_release(cma_heap->cma, pages, nr_pages);
+	/* release sg table */
+	sg_free_table(buffer->sg_table);
+	kfree(buffer->sg_table);
+}
+
+static struct ion_heap_ops ion_cma_ops = {
+	.allocate = ion_cma_allocate,
+	.free = ion_cma_free,
+	.map_user = ion_heap_map_user,
+	.map_kernel = ion_heap_map_kernel,
+	.unmap_kernel = ion_heap_unmap_kernel,
+};
+
+static struct ion_heap *__ion_cma_heap_create(struct cma *cma)
+{
+	struct ion_cma_heap *cma_heap;
+
+	cma_heap = kzalloc(sizeof(*cma_heap), GFP_KERNEL);
+
+	if (!cma_heap)
+		return ERR_PTR(-ENOMEM);
+
+	cma_heap->heap.ops = &ion_cma_ops;
+	cma_heap->cma = cma;
+	cma_heap->heap.type = ION_HEAP_TYPE_DMA;
+	return &cma_heap->heap;
+}
+
+static int __ion_add_cma_heaps(struct cma *cma, void *data)
+{
+	struct ion_heap *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

@@ -0,0 +1,286 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ION Memory Allocator generic heap helpers
+ *
+ * Copyright (C) 2011 Google, Inc.
+ */
+
+#include <linux/err.h>
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include <linux/mm.h>
+#include <linux/rtmutex.h>
+#include <linux/sched.h>
+#include <uapi/linux/sched/types.h>
+#include <linux/scatterlist.h>
+#include <linux/vmalloc.h>
+
+#include "ion.h"
+
+void *ion_heap_map_kernel(struct ion_heap *heap,
+			  struct ion_buffer *buffer)
+{
+	struct sg_page_iter piter;
+	void *vaddr;
+	pgprot_t pgprot;
+	struct sg_table *table = buffer->sg_table;
+	int npages = PAGE_ALIGN(buffer->size) / PAGE_SIZE;
+	struct page **pages = vmalloc(array_size(npages,
+						 sizeof(struct page *)));
+	struct page **tmp = pages;
+
+	if (!pages)
+		return ERR_PTR(-ENOMEM);
+
+	if (buffer->flags & ION_FLAG_CACHED)
+		pgprot = PAGE_KERNEL;
+	else
+		pgprot = pgprot_writecombine(PAGE_KERNEL);
+
+	for_each_sgtable_page(table, &piter, 0) {
+		BUG_ON(tmp - pages >= npages);
+		*tmp++ = sg_page_iter_page(&piter);
+	}
+
+	vaddr = vmap(pages, npages, VM_MAP, pgprot);
+	vfree(pages);
+
+	if (!vaddr)
+		return ERR_PTR(-ENOMEM);
+
+	return vaddr;
+}
+
+void ion_heap_unmap_kernel(struct ion_heap *heap,
+			   struct ion_buffer *buffer)
+{
+	vunmap(buffer->vaddr);
+}
+
+int ion_heap_map_user(struct ion_heap *heap, struct ion_buffer *buffer,
+		      struct vm_area_struct *vma)
+{
+	struct sg_page_iter piter;
+	struct sg_table *table = buffer->sg_table;
+	unsigned long addr = vma->vm_start;
+	int ret;
+
+	for_each_sgtable_page(table, &piter, vma->vm_pgoff) {
+		struct page *page = sg_page_iter_page(&piter);
+
+		ret = remap_pfn_range(vma, addr, page_to_pfn(page), PAGE_SIZE,
+				      vma->vm_page_prot);
+		if (ret)
+			return ret;
+		addr += PAGE_SIZE;
+		if (addr >= vma->vm_end)
+			return 0;
+	}
+
+	return 0;
+}
+
+static int ion_heap_clear_pages(struct page **pages, int num, pgprot_t pgprot)
+{
+	void *addr = vmap(pages, num, VM_MAP, pgprot);
+
+	if (!addr)
+		return -ENOMEM;
+	memset(addr, 0, PAGE_SIZE * num);
+	vunmap(addr);
+
+	return 0;
+}
+
+static int ion_heap_sglist_zero(struct sg_table *sgt, pgprot_t pgprot)
+{
+	int p = 0;
+	int ret = 0;
+	struct sg_page_iter piter;
+	struct page *pages[32];
+
+	for_each_sgtable_page(sgt, &piter, 0) {
+		pages[p++] = sg_page_iter_page(&piter);
+		if (p == ARRAY_SIZE(pages)) {
+			ret = ion_heap_clear_pages(pages, p, pgprot);
+			if (ret)
+				return ret;
+			p = 0;
+		}
+	}
+	if (p)
+		ret = ion_heap_clear_pages(pages, p, pgprot);
+
+	return ret;
+}
+
+int ion_heap_buffer_zero(struct ion_buffer *buffer)
+{
+	struct sg_table *table = buffer->sg_table;
+	pgprot_t pgprot;
+
+	if (buffer->flags & ION_FLAG_CACHED)
+		pgprot = PAGE_KERNEL;
+	else
+		pgprot = pgprot_writecombine(PAGE_KERNEL);
+
+	return ion_heap_sglist_zero(table, pgprot);
+}
+
+void ion_heap_freelist_add(struct ion_heap *heap, struct ion_buffer *buffer)
+{
+	spin_lock(&heap->free_lock);
+	list_add(&buffer->list, &heap->free_list);
+	heap->free_list_size += buffer->size;
+	spin_unlock(&heap->free_lock);
+	wake_up(&heap->waitqueue);
+}
+
+size_t ion_heap_freelist_size(struct ion_heap *heap)
+{
+	size_t size;
+
+	spin_lock(&heap->free_lock);
+	size = heap->free_list_size;
+	spin_unlock(&heap->free_lock);
+
+	return size;
+}
+
+static size_t _ion_heap_freelist_drain(struct ion_heap *heap, size_t size,
+				       bool skip_pools)
+{
+	struct ion_buffer *buffer;
+	size_t total_drained = 0;
+
+	if (ion_heap_freelist_size(heap) == 0)
+		return 0;
+
+	spin_lock(&heap->free_lock);
+	if (size == 0)
+		size = heap->free_list_size;
+
+	while (!list_empty(&heap->free_list)) {
+		if (total_drained >= size)
+			break;
+		buffer = list_first_entry(&heap->free_list, struct ion_buffer,
+					  list);
+		list_del(&buffer->list);
+		heap->free_list_size -= buffer->size;
+		if (skip_pools)
+			buffer->private_flags |= ION_PRIV_FLAG_SHRINKER_FREE;
+		total_drained += buffer->size;
+		spin_unlock(&heap->free_lock);
+		ion_buffer_destroy(buffer);
+		spin_lock(&heap->free_lock);
+	}
+	spin_unlock(&heap->free_lock);
+
+	return total_drained;
+}
+
+size_t ion_heap_freelist_drain(struct ion_heap *heap, size_t size)
+{
+	return _ion_heap_freelist_drain(heap, size, false);
+}
+
+size_t ion_heap_freelist_shrink(struct ion_heap *heap, size_t size)
+{
+	return _ion_heap_freelist_drain(heap, size, true);
+}
+
+static int ion_heap_deferred_free(void *data)
+{
+	struct ion_heap *heap = data;
+
+	while (true) {
+		struct ion_buffer *buffer;
+
+		wait_event_freezable(heap->waitqueue,
+				     ion_heap_freelist_size(heap) > 0);
+
+		spin_lock(&heap->free_lock);
+		if (list_empty(&heap->free_list)) {
+			spin_unlock(&heap->free_lock);
+			continue;
+		}
+		buffer = list_first_entry(&heap->free_list, struct ion_buffer,
+					  list);
+		list_del(&buffer->list);
+		heap->free_list_size -= buffer->size;
+		spin_unlock(&heap->free_lock);
+		ion_buffer_destroy(buffer);
+	}
+
+	return 0;
+}
+
+int ion_heap_init_deferred_free(struct ion_heap *heap)
+{
+	INIT_LIST_HEAD(&heap->free_list);
+	init_waitqueue_head(&heap->waitqueue);
+	heap->task = kthread_run(ion_heap_deferred_free, heap,
+				 "%s", heap->name);
+	if (IS_ERR(heap->task)) {
+		pr_err("%s: creating thread for deferred free failed\n",
+		       __func__);
+		return PTR_ERR_OR_ZERO(heap->task);
+	}
+	sched_set_normal(heap->task, 19);
+
+	return 0;
+}
+
+static unsigned long ion_heap_shrink_count(struct shrinker *shrinker,
+					   struct shrink_control *sc)
+{
+	struct ion_heap *heap = container_of(shrinker, struct ion_heap,
+					     shrinker);
+	int total = 0;
+
+	total = ion_heap_freelist_size(heap) / PAGE_SIZE;
+
+	if (heap->ops->shrink)
+		total += heap->ops->shrink(heap, sc->gfp_mask, 0);
+
+	return total;
+}
+
+static unsigned long ion_heap_shrink_scan(struct shrinker *shrinker,
+					  struct shrink_control *sc)
+{
+	struct ion_heap *heap = container_of(shrinker, struct ion_heap,
+					     shrinker);
+	int freed = 0;
+	int to_scan = sc->nr_to_scan;
+
+	if (to_scan == 0)
+		return 0;
+
+	/*
+	 * shrink the free list first, no point in zeroing the memory if we're
+	 * just going to reclaim it. Also, skip any possible page pooling.
+	 */
+	if (heap->flags & ION_HEAP_FLAG_DEFER_FREE)
+		freed = ion_heap_freelist_shrink(heap, to_scan * PAGE_SIZE) /
+				PAGE_SIZE;
+
+	to_scan -= freed;
+	if (to_scan <= 0)
+		return freed;
+
+	if (heap->ops->shrink)
+		freed += heap->ops->shrink(heap, sc->gfp_mask, to_scan);
+
+	return freed;
+}
+
+int ion_heap_init_shrinker(struct ion_heap *heap)
+{
+	heap->shrinker.count_objects = ion_heap_shrink_count;
+	heap->shrinker.scan_objects = ion_heap_shrink_scan;
+	heap->shrinker.seeks = DEFAULT_SEEKS;
+	heap->shrinker.batch = 0;
+
+	return register_shrinker(&heap->shrinker);
+}

drivers/staging/android/ion/ion_page_pool.c

@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ION Memory Allocator page pool helpers
+ *
+ * Copyright (C) 2011 Google, Inc.
+ */
+
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/swap.h>
+#include <linux/sched/signal.h>
+
+#include "ion.h"
+
+static inline struct page *ion_page_pool_alloc_pages(struct ion_page_pool *pool)
+{
+	if (fatal_signal_pending(current))
+		return NULL;
+	return alloc_pages(pool->gfp_mask, pool->order);
+}
+
+static void ion_page_pool_free_pages(struct ion_page_pool *pool,
+				     struct page *page)
+{
+	__free_pages(page, pool->order);
+}
+
+static void ion_page_pool_add(struct ion_page_pool *pool, struct page *page)
+{
+	mutex_lock(&pool->mutex);
+	if (PageHighMem(page)) {
+		list_add_tail(&page->lru, &pool->high_items);
+		pool->high_count++;
+	} else {
+		list_add_tail(&page->lru, &pool->low_items);
+		pool->low_count++;
+	}
+
+	mod_node_page_state(page_pgdat(page), NR_KERNEL_MISC_RECLAIMABLE,
+			    1 << pool->order);
+	mutex_unlock(&pool->mutex);
+}
+
+static struct page *ion_page_pool_remove(struct ion_page_pool *pool, bool high)
+{
+	struct page *page;
+
+	if (high) {
+		BUG_ON(!pool->high_count);
+		page = list_first_entry(&pool->high_items, struct page, lru);
+		pool->high_count--;
+	} else {
+		BUG_ON(!pool->low_count);
+		page = list_first_entry(&pool->low_items, struct page, lru);
+		pool->low_count--;
+	}
+
+	list_del(&page->lru);
+	mod_node_page_state(page_pgdat(page), NR_KERNEL_MISC_RECLAIMABLE,
+			    -(1 << pool->order));
+	return page;
+}
+
+struct page *ion_page_pool_alloc(struct ion_page_pool *pool)
+{
+	struct page *page = NULL;
+
+	BUG_ON(!pool);
+
+	mutex_lock(&pool->mutex);
+	if (pool->high_count)
+		page = ion_page_pool_remove(pool, true);
+	else if (pool->low_count)
+		page = ion_page_pool_remove(pool, false);
+	mutex_unlock(&pool->mutex);
+
+	if (!page)
+		page = ion_page_pool_alloc_pages(pool);
+
+	return page;
+}
+
+void ion_page_pool_free(struct ion_page_pool *pool, struct page *page)
+{
+	BUG_ON(pool->order != compound_order(page));
+
+	ion_page_pool_add(pool, page);
+}
+
+static int ion_page_pool_total(struct ion_page_pool *pool, bool high)
+{
+	int count = pool->low_count;
+
+	if (high)
+		count += pool->high_count;
+
+	return count << pool->order;
+}
+
+int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
+			 int nr_to_scan)
+{
+	int freed = 0;
+	bool high;
+
+	if (current_is_kswapd())
+		high = true;
+	else
+		high = !!(gfp_mask & __GFP_HIGHMEM);
+
+	if (nr_to_scan == 0)
+		return ion_page_pool_total(pool, high);
+
+	while (freed < nr_to_scan) {
+		struct page *page;
+
+		mutex_lock(&pool->mutex);
+		if (pool->low_count) {
+			page = ion_page_pool_remove(pool, false);
+		} else if (high && pool->high_count) {
+			page = ion_page_pool_remove(pool, true);
+		} else {
+			mutex_unlock(&pool->mutex);
+			break;
+		}
+		mutex_unlock(&pool->mutex);
+		ion_page_pool_free_pages(pool, page);
+		freed += (1 << pool->order);
+	}
+
+	return freed;
+}
+
+struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order)
+{
+	struct ion_page_pool *pool = kmalloc(sizeof(*pool), GFP_KERNEL);
+
+	if (!pool)
+		return NULL;
+	pool->high_count = 0;
+	pool->low_count = 0;
+	INIT_LIST_HEAD(&pool->low_items);
+	INIT_LIST_HEAD(&pool->high_items);
+	pool->gfp_mask = gfp_mask | __GFP_COMP;
+	pool->order = order;
+	mutex_init(&pool->mutex);
+	plist_node_init(&pool->list, order);
+
+	return pool;
+}
+
+void ion_page_pool_destroy(struct ion_page_pool *pool)
+{
+	kfree(pool);
+}

drivers/staging/android/ion/ion_system_heap.c

@@ -0,0 +1,377 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ION Memory Allocator system heap exporter
+ *
+ * Copyright (C) 2011 Google, Inc.
+ */
+
+#include <asm/page.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/highmem.h>
+#include <linux/mm.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#include "ion.h"
+
+#define NUM_ORDERS ARRAY_SIZE(orders)
+
+static gfp_t high_order_gfp_flags = (GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN |
+				     __GFP_NORETRY) & ~__GFP_RECLAIM;
+static gfp_t low_order_gfp_flags  = GFP_HIGHUSER | __GFP_ZERO;
+static const unsigned int orders[] = {8, 4, 0};
+
+static int order_to_index(unsigned int order)
+{
+	int i;
+
+	for (i = 0; i < NUM_ORDERS; i++)
+		if (order == orders[i])
+			return i;
+	BUG();
+	return -1;
+}
+
+static inline unsigned int order_to_size(int order)
+{
+	return PAGE_SIZE << order;
+}
+
+struct ion_system_heap {
+	struct ion_heap heap;
+	struct ion_page_pool *pools[NUM_ORDERS];
+};
+
+static struct page *alloc_buffer_page(struct ion_system_heap *heap,
+				      struct ion_buffer *buffer,
+				      unsigned long order)
+{
+	struct ion_page_pool *pool = heap->pools[order_to_index(order)];
+
+	return ion_page_pool_alloc(pool);
+}
+
+static void free_buffer_page(struct ion_system_heap *heap,
+			     struct ion_buffer *buffer, struct page *page)
+{
+	struct ion_page_pool *pool;
+	unsigned int order = compound_order(page);
+
+	/* go to system */
+	if (buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE) {
+		__free_pages(page, order);
+		return;
+	}
+
+	pool = heap->pools[order_to_index(order)];
+
+	ion_page_pool_free(pool, page);
+}
+
+static struct page *alloc_largest_available(struct ion_system_heap *heap,
+					    struct ion_buffer *buffer,
+					    unsigned long size,
+					    unsigned int max_order)
+{
+	struct page *page;
+	int i;
+
+	for (i = 0; i < NUM_ORDERS; i++) {
+		if (size < order_to_size(orders[i]))
+			continue;
+		if (max_order < orders[i])
+			continue;
+
+		page = alloc_buffer_page(heap, buffer, orders[i]);
+		if (!page)
+			continue;
+
+		return page;
+	}
+
+	return NULL;
+}
+
+static int ion_system_heap_allocate(struct ion_heap *heap,
+				    struct ion_buffer *buffer,
+				    unsigned long size,
+				    unsigned long flags)
+{
+	struct ion_system_heap *sys_heap = container_of(heap,
+							struct ion_system_heap,
+							heap);
+	struct sg_table *table;
+	struct scatterlist *sg;
+	struct list_head pages;
+	struct page *page, *tmp_page;
+	int i = 0;
+	unsigned long size_remaining = PAGE_ALIGN(size);
+	unsigned int max_order = orders[0];
+
+	if (size / PAGE_SIZE > totalram_pages() / 2)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&pages);
+	while (size_remaining > 0) {
+		page = alloc_largest_available(sys_heap, buffer, size_remaining,
+					       max_order);
+		if (!page)
+			goto free_pages;
+		list_add_tail(&page->lru, &pages);
+		size_remaining -= page_size(page);
+		max_order = compound_order(page);
+		i++;
+	}
+	table = kmalloc(sizeof(*table), GFP_KERNEL);
+	if (!table)
+		goto free_pages;
+
+	if (sg_alloc_table(table, i, GFP_KERNEL))
+		goto free_table;
+
+	sg = table->sgl;
+	list_for_each_entry_safe(page, tmp_page, &pages, lru) {
+		sg_set_page(sg, page, page_size(page), 0);
+		sg = sg_next(sg);
+		list_del(&page->lru);
+	}
+
+	buffer->sg_table = table;
+	return 0;
+
+free_table:
+	kfree(table);
+free_pages:
+	list_for_each_entry_safe(page, tmp_page, &pages, lru)
+		free_buffer_page(sys_heap, buffer, page);
+	return -ENOMEM;
+}
+
+static void ion_system_heap_free(struct ion_buffer *buffer)
+{
+	struct ion_system_heap *sys_heap = container_of(buffer->heap,
+							struct ion_system_heap,
+							heap);
+	struct sg_table *table = buffer->sg_table;
+	struct scatterlist *sg;
+	int i;
+
+	/* zero the buffer before goto page pool */
+	if (!(buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE))
+		ion_heap_buffer_zero(buffer);
+
+	for_each_sgtable_sg(table, sg, i)
+		free_buffer_page(sys_heap, buffer, sg_page(sg));
+	sg_free_table(table);
+	kfree(table);
+}
+
+static int ion_system_heap_shrink(struct ion_heap *heap, gfp_t gfp_mask,
+				  int nr_to_scan)
+{
+	struct ion_page_pool *pool;
+	struct ion_system_heap *sys_heap;
+	int nr_total = 0;
+	int i, nr_freed;
+	int only_scan = 0;
+
+	sys_heap = container_of(heap, struct ion_system_heap, heap);
+
+	if (!nr_to_scan)
+		only_scan = 1;
+
+	for (i = 0; i < NUM_ORDERS; i++) {
+		pool = sys_heap->pools[i];
+
+		if (only_scan) {
+			nr_total += ion_page_pool_shrink(pool,
+							 gfp_mask,
+							 nr_to_scan);
+
+		} else {
+			nr_freed = ion_page_pool_shrink(pool,
+							gfp_mask,
+							nr_to_scan);
+			nr_to_scan -= nr_freed;
+			nr_total += nr_freed;
+			if (nr_to_scan <= 0)
+				break;
+		}
+	}
+	return nr_total;
+}
+
+static struct ion_heap_ops system_heap_ops = {
+	.allocate = ion_system_heap_allocate,
+	.free = ion_system_heap_free,
+	.map_kernel = ion_heap_map_kernel,
+	.unmap_kernel = ion_heap_unmap_kernel,
+	.map_user = ion_heap_map_user,
+	.shrink = ion_system_heap_shrink,
+};
+
+static void ion_system_heap_destroy_pools(struct ion_page_pool **pools)
+{
+	int i;
+
+	for (i = 0; i < NUM_ORDERS; i++)
+		if (pools[i])
+			ion_page_pool_destroy(pools[i]);
+}
+
+static int ion_system_heap_create_pools(struct ion_page_pool **pools)
+{
+	int i;
+
+	for (i = 0; i < NUM_ORDERS; i++) {
+		struct ion_page_pool *pool;
+		gfp_t gfp_flags = low_order_gfp_flags;
+
+		if (orders[i] > 4)
+			gfp_flags = high_order_gfp_flags;
+
+		pool = ion_page_pool_create(gfp_flags, orders[i]);
+		if (!pool)
+			goto err_create_pool;
+		pools[i] = pool;
+	}
+
+	return 0;
+
+err_create_pool:
+	ion_system_heap_destroy_pools(pools);
+	return -ENOMEM;
+}
+
+static struct ion_heap *__ion_system_heap_create(void)
+{
+	struct ion_system_heap *heap;
+
+	heap = kzalloc(sizeof(*heap), GFP_KERNEL);
+	if (!heap)
+		return ERR_PTR(-ENOMEM);
+	heap->heap.ops = &system_heap_ops;
+	heap->heap.type = ION_HEAP_TYPE_SYSTEM;
+	heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
+
+	if (ion_system_heap_create_pools(heap->pools))
+		goto free_heap;
+
+	return &heap->heap;
+
+free_heap:
+	kfree(heap);
+	return ERR_PTR(-ENOMEM);
+}
+
+static int ion_system_heap_create(void)
+{
+	struct ion_heap *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,
+					   unsigned long len,
+					   unsigned long flags)
+{
+	int order = get_order(len);
+	struct page *page;
+	struct sg_table *table;
+	unsigned long i;
+	int ret;
+
+	page = alloc_pages(low_order_gfp_flags | __GFP_NOWARN, order);
+	if (!page)
+		return -ENOMEM;
+
+	split_page(page, order);
+
+	len = PAGE_ALIGN(len);
+	for (i = len >> PAGE_SHIFT; i < (1 << order); i++)
+		__free_page(page + i);
+
+	table = kmalloc(sizeof(*table), GFP_KERNEL);
+	if (!table) {
+		ret = -ENOMEM;
+		goto free_pages;
+	}
+
+	ret = sg_alloc_table(table, 1, GFP_KERNEL);
+	if (ret)
+		goto free_table;
+
+	sg_set_page(table->sgl, page, len, 0);
+
+	buffer->sg_table = table;
+
+	return 0;
+
+free_table:
+	kfree(table);
+free_pages:
+	for (i = 0; i < len >> PAGE_SHIFT; i++)
+		__free_page(page + i);
+
+	return ret;
+}
+
+static void ion_system_contig_heap_free(struct ion_buffer *buffer)
+{
+	struct sg_table *table = buffer->sg_table;
+	struct page *page = sg_page(table->sgl);
+	unsigned long pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
+	unsigned long i;
+
+	for (i = 0; i < pages; i++)
+		__free_page(page + i);
+	sg_free_table(table);
+	kfree(table);
+}
+
+static struct ion_heap_ops kmalloc_ops = {
+	.allocate = ion_system_contig_heap_allocate,
+	.free = ion_system_contig_heap_free,
+	.map_kernel = ion_heap_map_kernel,
+	.unmap_kernel = ion_heap_unmap_kernel,
+	.map_user = ion_heap_map_user,
+};
+
+static struct ion_heap *__ion_system_contig_heap_create(void)
+{
+	struct ion_heap *heap;
+
+	heap = kzalloc(sizeof(*heap), GFP_KERNEL);
+	if (!heap)
+		return ERR_PTR(-ENOMEM);
+	heap->ops = &kmalloc_ops;
+	heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
+	heap->name = "ion_system_contig_heap";
+
+	return heap;
+}
+
+static int ion_system_contig_heap_create(void)
+{
+	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);

drivers/staging/android/uapi/ion.h

@@ -0,0 +1,127 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * drivers/staging/android/uapi/ion.h
+ *
+ * Copyright (C) 2011 Google, Inc.
+ */
+
+#ifndef _UAPI_LINUX_ION_H
+#define _UAPI_LINUX_ION_H
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+/**
+ * enum ion_heap_types - list of all possible types of heaps
+ * @ION_HEAP_TYPE_SYSTEM:	 memory allocated via vmalloc
+ * @ION_HEAP_TYPE_SYSTEM_CONTIG: memory allocated via kmalloc
+ * @ION_HEAP_TYPE_CARVEOUT:	 memory allocated from a prereserved
+ *				 carveout heap, allocations are physically
+ *				 contiguous
+ * @ION_HEAP_TYPE_DMA:		 memory allocated via DMA API
+ * @ION_NUM_HEAPS:		 helper for iterating over heaps, a bit mask
+ *				 is used to identify the heaps, so only 32
+ *				 total heap types are supported
+ */
+enum ion_heap_type {
+	ION_HEAP_TYPE_SYSTEM,
+	ION_HEAP_TYPE_SYSTEM_CONTIG,
+	ION_HEAP_TYPE_CARVEOUT,
+	ION_HEAP_TYPE_CHUNK,
+	ION_HEAP_TYPE_DMA,
+	ION_HEAP_TYPE_CUSTOM, /*
+			       * must be last so device specific heaps always
+			       * are at the end of this enum
+			       */
+};
+
+#define ION_NUM_HEAP_IDS		(sizeof(unsigned int) * 8)
+
+/**
+ * allocation flags - the lower 16 bits are used by core ion, the upper 16
+ * bits are reserved for use by the heaps themselves.
+ */
+
+/*
+ * mappings of this buffer should be cached, ion will do cache maintenance
+ * when the buffer is mapped for dma
+ */
+#define ION_FLAG_CACHED 1
+
+/**
+ * DOC: Ion Userspace API
+ *
+ * create a client by opening /dev/ion
+ * most operations handled via following ioctls
+ *
+ */
+
+/**
+ * struct ion_allocation_data - metadata passed from userspace for allocations
+ * @len:		size of the allocation
+ * @heap_id_mask:	mask of heap ids to allocate from
+ * @flags:		flags passed to heap
+ * @handle:		pointer that will be populated with a cookie to use to
+ *			refer to this allocation
+ *
+ * Provided by userspace as an argument to the ioctl
+ */
+struct ion_allocation_data {
+	__u64 len;
+	__u32 heap_id_mask;
+	__u32 flags;
+	__u32 fd;
+	__u32 unused;
+};
+
+#define MAX_HEAP_NAME			32
+
+/**
+ * struct ion_heap_data - data about a heap
+ * @name - first 32 characters of the heap name
+ * @type - heap type
+ * @heap_id - heap id for the heap
+ */
+struct ion_heap_data {
+	char name[MAX_HEAP_NAME];
+	__u32 type;
+	__u32 heap_id;
+	__u32 reserved0;
+	__u32 reserved1;
+	__u32 reserved2;
+};
+
+/**
+ * struct ion_heap_query - collection of data about all heaps
+ * @cnt - total number of heaps to be copied
+ * @heaps - buffer to copy heap data
+ */
+struct ion_heap_query {
+	__u32 cnt; /* Total number of heaps to be copied */
+	__u32 reserved0; /* align to 64bits */
+	__u64 heaps; /* buffer to be populated */
+	__u32 reserved1;
+	__u32 reserved2;
+};
+
+#define ION_IOC_MAGIC		'I'
+
+/**
+ * DOC: ION_IOC_ALLOC - allocate memory
+ *
+ * Takes an ion_allocation_data struct and returns it with the handle field
+ * populated with the opaque handle for the allocation.
+ */
+#define ION_IOC_ALLOC		_IOWR(ION_IOC_MAGIC, 0, \
+				      struct ion_allocation_data)
+
+/**
+ * DOC: ION_IOC_HEAP_QUERY - information about available heaps
+ *
+ * Takes an ion_heap_query structure and populates information about
+ * available Ion heaps.
+ */
+#define ION_IOC_HEAP_QUERY     _IOWR(ION_IOC_MAGIC, 8, \
+					struct ion_heap_query)
+
+#endif /* _UAPI_LINUX_ION_H */

tools/testing/selftests/Makefile

@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
-TARGETS = arm64
+TARGETS = android
+TARGETS += arm64
 TARGETS += bpf
 TARGETS += breakpoints
 TARGETS += capabilities

tools/testing/selftests/android/Makefile

@@ -0,0 +1,39 @@
+# SPDX-License-Identifier: GPL-2.0-only
+SUBDIRS := ion
+
+TEST_PROGS := run.sh
+
+.PHONY: all clean
+
+include ../lib.mk
+
+all:
+	@for DIR in $(SUBDIRS); do		\
+		BUILD_TARGET=$(OUTPUT)/$$DIR;	\
+		mkdir $$BUILD_TARGET  -p;	\
+		make OUTPUT=$$BUILD_TARGET -C $$DIR $@;\
+		#SUBDIR test prog name should be in the form: SUBDIR_test.sh \
+		TEST=$$DIR"_test.sh"; \
+		if [ -e $$DIR/$$TEST ]; then \
+			rsync -a $$DIR/$$TEST $$BUILD_TARGET/; \
+		fi \
+	done
+
+override define INSTALL_RULE
+	mkdir -p $(INSTALL_PATH)
+install -t $(INSTALL_PATH) $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES)  $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES)
+
+	@for SUBDIR in $(SUBDIRS); do \
+		BUILD_TARGET=$(OUTPUT)/$$SUBDIR;	\
+		mkdir $$BUILD_TARGET  -p;	\
+		$(MAKE) OUTPUT=$$BUILD_TARGET -C $$SUBDIR INSTALL_PATH=$(INSTALL_PATH)/$$SUBDIR install; \
+	done;
+endef
+
+override define CLEAN
+	@for DIR in $(SUBDIRS); do		\
+		BUILD_TARGET=$(OUTPUT)/$$DIR;	\
+		mkdir $$BUILD_TARGET  -p;	\
+		make OUTPUT=$$BUILD_TARGET -C $$DIR $@;\
+	done
+endef

tools/testing/selftests/android/config

@@ -0,0 +1,5 @@
+CONFIG_ANDROID=y
+CONFIG_STAGING=y
+CONFIG_ION=y
+CONFIG_ION_SYSTEM_HEAP=y
+CONFIG_DRM_VGEM=y

tools/testing/selftests/android/ion/.gitignore

@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+ionapp_export
+ionapp_import
+ionmap_test

tools/testing/selftests/android/ion/Makefile

@@ -0,0 +1,20 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+INCLUDEDIR := -I. -I../../../../../drivers/staging/android/uapi/ -I../../../../../usr/include/
+CFLAGS := $(CFLAGS) $(INCLUDEDIR) -Wall -O2 -g
+
+TEST_GEN_FILES := ionapp_export ionapp_import ionmap_test
+
+all: $(TEST_GEN_FILES)
+
+$(TEST_GEN_FILES): ipcsocket.c ionutils.c
+
+TEST_PROGS := ion_test.sh
+
+KSFT_KHDR_INSTALL := 1
+top_srcdir = ../../../../..
+include ../../lib.mk
+
+$(OUTPUT)/ionapp_export: ionapp_export.c ipcsocket.c ionutils.c
+$(OUTPUT)/ionapp_import: ionapp_import.c ipcsocket.c ionutils.c
+$(OUTPUT)/ionmap_test: ionmap_test.c ionutils.c ipcsocket.c

tools/testing/selftests/android/ion/README

@@ -0,0 +1,101 @@
+ION BUFFER SHARING UTILITY
+==========================
+File: ion_test.sh : Utility to test ION driver buffer sharing mechanism.
+Author: Pintu Kumar <pintu.ping@gmail.com>
+
+Introduction:
+-------------
+This is a test utility to verify ION buffer sharing in user space
+between 2 independent processes.
+It uses unix domain socket (with SCM_RIGHTS) as IPC to transfer an FD to
+another process to share the same buffer.
+This utility demonstrates how ION buffer sharing can be implemented between
+two user space processes, using various heap types.
+The following heap types are supported by ION driver.
+ION_HEAP_TYPE_SYSTEM (0)
+ION_HEAP_TYPE_SYSTEM_CONTIG (1)
+ION_HEAP_TYPE_CARVEOUT (2)
+ION_HEAP_TYPE_CHUNK (3)
+ION_HEAP_TYPE_DMA (4)
+
+By default only the SYSTEM and SYSTEM_CONTIG heaps are supported.
+Each heap is associated with the respective heap id.
+This utility is designed in the form of client/server program.
+The server part (ionapp_export) is the exporter of the buffer.
+It is responsible for creating an ION client, allocating the buffer based on
+the heap id, writing some data to this buffer and then exporting the FD
+(associated with this buffer) to another process using socket IPC.
+This FD is called as buffer FD (which is different than the ION client FD).
+
+The client part (ionapp_import) is the importer of the buffer.
+It retrives the FD from the socket data and installs into its address space.
+This new FD internally points to the same kernel buffer.
+So first it reads the data that is stored in this buffer and prints it.
+Then it writes the different size of data (it could be different data) to the
+same buffer.
+Finally the buffer FD must be closed by both the exporter and importer.
+Thus the same kernel buffer is shared among two user space processes using
+ION driver and only one time allocation.
+
+Prerequisite:
+-------------
+This utility works only if /dev/ion interface is present.
+The following configs needs to be enabled in kernel to include ion driver.
+CONFIG_ANDROID=y
+CONFIG_STAGING=y
+CONFIG_ION=y
+CONFIG_ION_SYSTEM_HEAP=y
+
+This utility requires to be run as root user.
+
+
+Compile and test:
+-----------------
+This utility is made to be run as part of kselftest framework in kernel.
+To compile and run using kselftest you can simply do the following from the
+kernel top directory.
+linux$ make TARGETS=android kselftest
+Or you can also use:
+linux$ make -C tools/testing/selftests TARGETS=android run_tests
+Using the selftest it can directly execute the ion_test.sh script to test the
+buffer sharing using ion system heap.
+Currently the heap size is hard coded as just 10 bytes inside this script.
+You need to be a root user to run under selftest.
+
+You can also compile and test manually using the following steps:
+ion$ make
+These will generate 2 executable: ionapp_export, ionapp_import
+Now you can run the export and import manually by specifying the heap type
+and the heap size.
+You can also directly execute the shell script to run the test automatically.
+Simply use the following command to run the test.
+ion$ sudo ./ion_test.sh
+
+Test Results:
+-------------
+The utility is verified on Ubuntu-32 bit system with Linux Kernel 4.14.
+Here is the snapshot of the test result using kselftest.
+
+linux# make TARGETS=android kselftest
+heap_type: 0, heap_size: 10
+--------------------------------------
+heap type: 0
+  heap id: 1
+heap name: ion_system_heap
+--------------------------------------
+Fill buffer content:
+0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd
+Sharing fd: 6, Client fd: 5
+<ion_close_buffer_fd>: buffer release successfully....
+Received buffer fd: 4
+Read buffer content:
+0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0x0 0x0 0x0 0x0 0x0 0x0
+0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0
+Fill buffer content:
+0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd
+0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd 0xfd
+0xfd 0xfd
+<ion_close_buffer_fd>: buffer release successfully....
+ion_test.sh: heap_type: 0 - [PASS]
+
+ion_test.sh: done

tools/testing/selftests/android/ion/ion.h

@@ -0,0 +1,134 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * ion.h
+ *
+ * Copyright (C) 2011 Google, Inc.
+ */
+
+/* This file is copied from drivers/staging/android/uapi/ion.h
+ * This local copy is required for the selftest to pass, when build
+ * outside the kernel source tree.
+ * Please keep this file in sync with its original file until the
+ * ion driver is moved outside the staging tree.
+ */
+
+#ifndef _UAPI_LINUX_ION_H
+#define _UAPI_LINUX_ION_H
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+/**
+ * enum ion_heap_types - list of all possible types of heaps
+ * @ION_HEAP_TYPE_SYSTEM:	 memory allocated via vmalloc
+ * @ION_HEAP_TYPE_SYSTEM_CONTIG: memory allocated via kmalloc
+ * @ION_HEAP_TYPE_CARVEOUT:	 memory allocated from a prereserved
+ *				 carveout heap, allocations are physically
+ *				 contiguous
+ * @ION_HEAP_TYPE_DMA:		 memory allocated via DMA API
+ * @ION_NUM_HEAPS:		 helper for iterating over heaps, a bit mask
+ *				 is used to identify the heaps, so only 32
+ *				 total heap types are supported
+ */
+enum ion_heap_type {
+	ION_HEAP_TYPE_SYSTEM,
+	ION_HEAP_TYPE_SYSTEM_CONTIG,
+	ION_HEAP_TYPE_CARVEOUT,
+	ION_HEAP_TYPE_CHUNK,
+	ION_HEAP_TYPE_DMA,
+	ION_HEAP_TYPE_CUSTOM, /*
+			       * must be last so device specific heaps always
+			       * are at the end of this enum
+			       */
+};
+
+#define ION_NUM_HEAP_IDS		(sizeof(unsigned int) * 8)
+
+/**
+ * allocation flags - the lower 16 bits are used by core ion, the upper 16
+ * bits are reserved for use by the heaps themselves.
+ */
+
+/*
+ * mappings of this buffer should be cached, ion will do cache maintenance
+ * when the buffer is mapped for dma
+ */
+#define ION_FLAG_CACHED 1
+
+/**
+ * DOC: Ion Userspace API
+ *
+ * create a client by opening /dev/ion
+ * most operations handled via following ioctls
+ *
+ */
+
+/**
+ * struct ion_allocation_data - metadata passed from userspace for allocations
+ * @len:		size of the allocation
+ * @heap_id_mask:	mask of heap ids to allocate from
+ * @flags:		flags passed to heap
+ * @handle:		pointer that will be populated with a cookie to use to
+ *			refer to this allocation
+ *
+ * Provided by userspace as an argument to the ioctl
+ */
+struct ion_allocation_data {
+	__u64 len;
+	__u32 heap_id_mask;
+	__u32 flags;
+	__u32 fd;
+	__u32 unused;
+};
+
+#define MAX_HEAP_NAME			32
+
+/**
+ * struct ion_heap_data - data about a heap
+ * @name - first 32 characters of the heap name
+ * @type - heap type
+ * @heap_id - heap id for the heap
+ */
+struct ion_heap_data {
+	char name[MAX_HEAP_NAME];
+	__u32 type;
+	__u32 heap_id;
+	__u32 reserved0;
+	__u32 reserved1;
+	__u32 reserved2;
+};
+
+/**
+ * struct ion_heap_query - collection of data about all heaps
+ * @cnt - total number of heaps to be copied
+ * @heaps - buffer to copy heap data
+ */
+struct ion_heap_query {
+	__u32 cnt; /* Total number of heaps to be copied */
+	__u32 reserved0; /* align to 64bits */
+	__u64 heaps; /* buffer to be populated */
+	__u32 reserved1;
+	__u32 reserved2;
+};
+
+#define ION_IOC_MAGIC		'I'
+
+/**
+ * DOC: ION_IOC_ALLOC - allocate memory
+ *
+ * Takes an ion_allocation_data struct and returns it with the handle field
+ * populated with the opaque handle for the allocation.
+ */
+#define ION_IOC_ALLOC		_IOWR(ION_IOC_MAGIC, 0, \
+				      struct ion_allocation_data)
+
+/**
+ * DOC: ION_IOC_HEAP_QUERY - information about available heaps
+ *
+ * Takes an ion_heap_query structure and populates information about
+ * available Ion heaps.
+ */
+#define ION_IOC_HEAP_QUERY     _IOWR(ION_IOC_MAGIC, 8, \
+					struct ion_heap_query)
+
+#endif /* _UAPI_LINUX_ION_H */

tools/testing/selftests/android/ion/ion_test.sh

@@ -0,0 +1,58 @@
+#!/bin/bash
+
+heapsize=4096
+TCID="ion_test.sh"
+errcode=0
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+run_test()
+{
+	heaptype=$1
+	./ionapp_export -i $heaptype -s $heapsize &
+	sleep 1
+	./ionapp_import
+	if [ $? -ne 0 ]; then
+		echo "$TCID: heap_type: $heaptype - [FAIL]"
+		errcode=1
+	else
+		echo "$TCID: heap_type: $heaptype - [PASS]"
+	fi
+	sleep 1
+	echo ""
+}
+
+check_root()
+{
+	uid=$(id -u)
+	if [ $uid -ne 0 ]; then
+		echo $TCID: must be run as root >&2
+		exit $ksft_skip
+	fi
+}
+
+check_device()
+{
+	DEVICE=/dev/ion
+	if [ ! -e $DEVICE ]; then
+		echo $TCID: No $DEVICE device found >&2
+		echo $TCID: May be CONFIG_ION is not set >&2
+		exit $ksft_skip
+	fi
+}
+
+main_function()
+{
+	check_device
+	check_root
+
+	# ION_SYSTEM_HEAP TEST
+	run_test 0
+	# ION_SYSTEM_CONTIG_HEAP TEST
+	run_test 1
+}
+
+main_function
+echo "$TCID: done"
+exit $errcode

tools/testing/selftests/android/ion/ionapp_export.c

@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ionapp_export.c
+ *
+ * It is a user space utility to create and export android
+ * ion memory buffer fd to another process using unix domain socket as IPC.
+ * This acts like a server for ionapp_import(client).
+ * So, this server has to be started first before the client.
+ *
+ * Copyright (C) 2017 Pintu Kumar <pintu.ping@gmail.com>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/time.h>
+#include "ionutils.h"
+#include "ipcsocket.h"
+
+
+void print_usage(int argc, char *argv[])
+{
+	printf("Usage: %s [-h <help>] [-i <heap id>] [-s <size in bytes>]\n",
+		argv[0]);
+}
+
+int main(int argc, char *argv[])
+{
+	int opt, ret, status, heapid;
+	int sockfd, client_fd, shared_fd;
+	unsigned char *map_buf;
+	unsigned long map_len, heap_type, heap_size, flags;
+	struct ion_buffer_info info;
+	struct socket_info skinfo;
+
+	if (argc < 2) {
+		print_usage(argc, argv);
+		return -1;
+	}
+
+	heap_size = 0;
+	flags = 0;
+	heap_type = ION_HEAP_TYPE_SYSTEM;
+
+	while ((opt = getopt(argc, argv, "hi:s:")) != -1) {
+		switch (opt) {
+		case 'h':
+			print_usage(argc, argv);
+			exit(0);
+			break;
+		case 'i':
+			heapid = atoi(optarg);
+			switch (heapid) {
+			case 0:
+				heap_type = ION_HEAP_TYPE_SYSTEM;
+				break;
+			case 1:
+				heap_type = ION_HEAP_TYPE_SYSTEM_CONTIG;
+				break;
+			default:
+				printf("ERROR: heap type not supported\n");
+				exit(1);
+			}
+			break;
+		case 's':
+			heap_size = atoi(optarg);
+			break;
+		default:
+			print_usage(argc, argv);
+			exit(1);
+			break;
+		}
+	}
+
+	if (heap_size <= 0) {
+		printf("heap_size cannot be 0\n");
+		print_usage(argc, argv);
+		exit(1);
+	}
+
+	printf("heap_type: %ld, heap_size: %ld\n", heap_type, heap_size);
+	info.heap_type = heap_type;
+	info.heap_size = heap_size;
+	info.flag_type = flags;
+
+	/* This is server: open the socket connection first */
+	/* Here; 1 indicates server or exporter */
+	status = opensocket(&sockfd, SOCKET_NAME, 1);
+	if (status < 0) {
+		fprintf(stderr, "<%s>: Failed opensocket.\n", __func__);
+		goto err_socket;
+	}
+	skinfo.sockfd = sockfd;
+
+	ret = ion_export_buffer_fd(&info);
+	if (ret < 0) {
+		fprintf(stderr, "FAILED: ion_get_buffer_fd\n");
+		goto err_export;
+	}
+	client_fd = info.ionfd;
+	shared_fd = info.buffd;
+	map_buf = info.buffer;
+	map_len = info.buflen;
+	write_buffer(map_buf, map_len);
+
+	/* share ion buf fd with other user process */
+	printf("Sharing fd: %d, Client fd: %d\n", shared_fd, client_fd);
+	skinfo.datafd = shared_fd;
+	skinfo.buflen = map_len;
+
+	ret = socket_send_fd(&skinfo);
+	if (ret < 0) {
+		fprintf(stderr, "FAILED: socket_send_fd\n");
+		goto err_send;
+	}
+
+err_send:
+err_export:
+	ion_close_buffer_fd(&info);
+
+err_socket:
+	closesocket(sockfd, SOCKET_NAME);
+
+	return 0;
+}

tools/testing/selftests/android/ion/ionapp_import.c

@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ionapp_import.c
+ *
+ * It is a user space utility to receive android ion memory buffer fd
+ * over unix domain socket IPC that can be exported by ionapp_export.
+ * This acts like a client for ionapp_export.
+ *
+ * Copyright (C) 2017 Pintu Kumar <pintu.ping@gmail.com>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include "ionutils.h"
+#include "ipcsocket.h"
+
+
+int main(void)
+{
+	int ret, status;
+	int sockfd, shared_fd;
+	unsigned char *map_buf;
+	unsigned long map_len;
+	struct ion_buffer_info info;
+	struct socket_info skinfo;
+
+	/* This is the client part. Here 0 means client or importer */
+	status = opensocket(&sockfd, SOCKET_NAME, 0);
+	if (status < 0) {
+		fprintf(stderr, "No exporter exists...\n");
+		ret = status;
+		goto err_socket;
+	}
+
+	skinfo.sockfd = sockfd;
+
+	ret = socket_receive_fd(&skinfo);
+	if (ret < 0) {
+		fprintf(stderr, "Failed: socket_receive_fd\n");
+		goto err_recv;
+	}
+
+	shared_fd = skinfo.datafd;
+	printf("Received buffer fd: %d\n", shared_fd);
+	if (shared_fd <= 0) {
+		fprintf(stderr, "ERROR: improper buf fd\n");
+		ret = -1;
+		goto err_fd;
+	}
+
+	memset(&info, 0, sizeof(info));
+	info.buffd = shared_fd;
+	info.buflen = ION_BUFFER_LEN;
+
+	ret = ion_import_buffer_fd(&info);
+	if (ret < 0) {
+		fprintf(stderr, "Failed: ion_use_buffer_fd\n");
+		goto err_import;
+	}
+
+	map_buf = info.buffer;
+	map_len = info.buflen;
+	read_buffer(map_buf, map_len);
+
+	/* Write probably new data to the same buffer again */
+	map_len = ION_BUFFER_LEN;
+	write_buffer(map_buf, map_len);
+
+err_import:
+	ion_close_buffer_fd(&info);
+err_fd:
+err_recv:
+err_socket:
+	closesocket(sockfd, SOCKET_NAME);
+
+	return ret;
+}

tools/testing/selftests/android/ion/ionmap_test.c

@@ -0,0 +1,136 @@
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <linux/dma-buf.h>
+
+#include <drm/drm.h>
+
+#include "ion.h"
+#include "ionutils.h"
+
+int check_vgem(int fd)
+{
+	drm_version_t version = { 0 };
+	char name[5];
+	int ret;
+
+	version.name_len = 4;
+	version.name = name;
+
+	ret = ioctl(fd, DRM_IOCTL_VERSION, &version);
+	if (ret)
+		return 1;
+
+	return strcmp(name, "vgem");
+}
+
+int open_vgem(void)
+{
+	int i, fd;
+	const char *drmstr = "/dev/dri/card";
+
+	fd = -1;
+	for (i = 0; i < 16; i++) {
+		char name[80];
+
+		sprintf(name, "%s%u", drmstr, i);
+
+		fd = open(name, O_RDWR);
+		if (fd < 0)
+			continue;
+
+		if (check_vgem(fd)) {
+			close(fd);
+			continue;
+		} else {
+			break;
+		}
+
+	}
+	return fd;
+}
+
+int import_vgem_fd(int vgem_fd, int dma_buf_fd, uint32_t *handle)
+{
+	struct drm_prime_handle import_handle = { 0 };
+	int ret;
+
+	import_handle.fd = dma_buf_fd;
+	import_handle.flags = 0;
+	import_handle.handle = 0;
+
+	ret = ioctl(vgem_fd, DRM_IOCTL_PRIME_FD_TO_HANDLE, &import_handle);
+	if (ret == 0)
+		*handle = import_handle.handle;
+	return ret;
+}
+
+void close_handle(int vgem_fd, uint32_t handle)
+{
+	struct drm_gem_close close = { 0 };
+
+	close.handle = handle;
+	ioctl(vgem_fd, DRM_IOCTL_GEM_CLOSE, &close);
+}
+
+int main()
+{
+	int ret, vgem_fd;
+	struct ion_buffer_info info;
+	uint32_t handle = 0;
+	struct dma_buf_sync sync = { 0 };
+
+	info.heap_type = ION_HEAP_TYPE_SYSTEM;
+	info.heap_size = 4096;
+	info.flag_type = ION_FLAG_CACHED;
+
+	ret = ion_export_buffer_fd(&info);
+	if (ret < 0) {
+		printf("ion buffer alloc failed\n");
+		return -1;
+	}
+
+	vgem_fd = open_vgem();
+	if (vgem_fd < 0) {
+		ret = vgem_fd;
+		printf("Failed to open vgem\n");
+		goto out_ion;
+	}
+
+	ret = import_vgem_fd(vgem_fd, info.buffd, &handle);
+
+	if (ret < 0) {
+		printf("Failed to import buffer\n");
+		goto out_vgem;
+	}
+
+	sync.flags = DMA_BUF_SYNC_START | DMA_BUF_SYNC_RW;
+	ret = ioctl(info.buffd, DMA_BUF_IOCTL_SYNC, &sync);
+	if (ret)
+		printf("sync start failed %d\n", errno);
+
+	memset(info.buffer, 0xff, 4096);
+
+	sync.flags = DMA_BUF_SYNC_END | DMA_BUF_SYNC_RW;
+	ret = ioctl(info.buffd, DMA_BUF_IOCTL_SYNC, &sync);
+	if (ret)
+		printf("sync end failed %d\n", errno);
+
+	close_handle(vgem_fd, handle);
+	ret = 0;
+
+out_vgem:
+	close(vgem_fd);
+out_ion:
+	ion_close_buffer_fd(&info);
+	printf("done.\n");
+	return ret;
+}

tools/testing/selftests/android/ion/ionutils.c

@@ -0,0 +1,253 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+//#include <stdint.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include "ionutils.h"
+#include "ipcsocket.h"
+
+
+void write_buffer(void *buffer, unsigned long len)
+{
+	int i;
+	unsigned char *ptr = (unsigned char *)buffer;
+
+	if (!ptr) {
+		fprintf(stderr, "<%s>: Invalid buffer...\n", __func__);
+		return;
+	}
+
+	printf("Fill buffer content:\n");
+	memset(ptr, 0xfd, len);
+	for (i = 0; i < len; i++)
+		printf("0x%x ", ptr[i]);
+	printf("\n");
+}
+
+void read_buffer(void *buffer, unsigned long len)
+{
+	int i;
+	unsigned char *ptr = (unsigned char *)buffer;
+
+	if (!ptr) {
+		fprintf(stderr, "<%s>: Invalid buffer...\n", __func__);
+		return;
+	}
+
+	printf("Read buffer content:\n");
+	for (i = 0; i < len; i++)
+		printf("0x%x ", ptr[i]);
+	printf("\n");
+}
+
+int ion_export_buffer_fd(struct ion_buffer_info *ion_info)
+{
+	int i, ret, ionfd, buffer_fd;
+	unsigned int heap_id;
+	unsigned long maplen;
+	unsigned char *map_buffer;
+	struct ion_allocation_data alloc_data;
+	struct ion_heap_query query;
+	struct ion_heap_data heap_data[MAX_HEAP_COUNT];
+
+	if (!ion_info) {
+		fprintf(stderr, "<%s>: Invalid ion info\n", __func__);
+		return -1;
+	}
+
+	/* Create an ION client */
+	ionfd = open(ION_DEVICE, O_RDWR);
+	if (ionfd < 0) {
+		fprintf(stderr, "<%s>: Failed to open ion client: %s\n",
+			__func__, strerror(errno));
+		return -1;
+	}
+
+	memset(&query, 0, sizeof(query));
+	query.cnt = MAX_HEAP_COUNT;
+	query.heaps = (unsigned long int)&heap_data[0];
+	/* Query ION heap_id_mask from ION heap */
+	ret = ioctl(ionfd, ION_IOC_HEAP_QUERY, &query);
+	if (ret < 0) {
+		fprintf(stderr, "<%s>: Failed: ION_IOC_HEAP_QUERY: %s\n",
+			__func__, strerror(errno));
+		goto err_query;
+	}
+
+	heap_id = MAX_HEAP_COUNT + 1;
+	for (i = 0; i < query.cnt; i++) {
+		if (heap_data[i].type == ion_info->heap_type) {
+			heap_id = heap_data[i].heap_id;
+			break;
+		}
+	}
+
+	if (heap_id > MAX_HEAP_COUNT) {
+		fprintf(stderr, "<%s>: ERROR: heap type does not exists\n",
+			__func__);
+		goto err_heap;
+	}
+
+	alloc_data.len = ion_info->heap_size;
+	alloc_data.heap_id_mask = 1 << heap_id;
+	alloc_data.flags = ion_info->flag_type;
+
+	/* Allocate memory for this ION client as per heap_type */
+	ret = ioctl(ionfd, ION_IOC_ALLOC, &alloc_data);
+	if (ret < 0) {
+		fprintf(stderr, "<%s>: Failed: ION_IOC_ALLOC: %s\n",
+			__func__, strerror(errno));
+		goto err_alloc;
+	}
+
+	/* This will return a valid buffer fd */
+	buffer_fd = alloc_data.fd;
+	maplen = alloc_data.len;
+
+	if (buffer_fd < 0 || maplen <= 0) {
+		fprintf(stderr, "<%s>: Invalid map data, fd: %d, len: %ld\n",
+			__func__, buffer_fd, maplen);
+		goto err_fd_data;
+	}
+
+	/* Create memory mapped buffer for the buffer fd */
+	map_buffer = (unsigned char *)mmap(NULL, maplen, PROT_READ|PROT_WRITE,
+			MAP_SHARED, buffer_fd, 0);
+	if (map_buffer == MAP_FAILED) {
+		fprintf(stderr, "<%s>: Failed: mmap: %s\n",
+			__func__, strerror(errno));
+		goto err_mmap;
+	}
+
+	ion_info->ionfd = ionfd;
+	ion_info->buffd = buffer_fd;
+	ion_info->buffer = map_buffer;
+	ion_info->buflen = maplen;
+
+	return 0;
+
+	munmap(map_buffer, maplen);
+
+err_fd_data:
+err_mmap:
+	/* in case of error: close the buffer fd */
+	if (buffer_fd)
+		close(buffer_fd);
+
+err_query:
+err_heap:
+err_alloc:
+	/* In case of error: close the ion client fd */
+	if (ionfd)
+		close(ionfd);
+
+	return -1;
+}
+
+int ion_import_buffer_fd(struct ion_buffer_info *ion_info)
+{
+	int buffd;
+	unsigned char *map_buf;
+	unsigned long map_len;
+
+	if (!ion_info) {
+		fprintf(stderr, "<%s>: Invalid ion info\n", __func__);
+		return -1;
+	}
+
+	map_len = ion_info->buflen;
+	buffd = ion_info->buffd;
+
+	if (buffd < 0 || map_len <= 0) {
+		fprintf(stderr, "<%s>: Invalid map data, fd: %d, len: %ld\n",
+			__func__, buffd, map_len);
+		goto err_buffd;
+	}
+
+	map_buf = (unsigned char *)mmap(NULL, map_len, PROT_READ|PROT_WRITE,
+			MAP_SHARED, buffd, 0);
+	if (map_buf == MAP_FAILED) {
+		printf("<%s>: Failed - mmap: %s\n",
+			__func__, strerror(errno));
+		goto err_mmap;
+	}
+
+	ion_info->buffer = map_buf;
+	ion_info->buflen = map_len;
+
+	return 0;
+
+err_mmap:
+	if (buffd)
+		close(buffd);
+
+err_buffd:
+	return -1;
+}
+
+void ion_close_buffer_fd(struct ion_buffer_info *ion_info)
+{
+	if (ion_info) {
+		/* unmap the buffer properly in the end */
+		munmap(ion_info->buffer, ion_info->buflen);
+		/* close the buffer fd */
+		if (ion_info->buffd > 0)
+			close(ion_info->buffd);
+		/* Finally, close the client fd */
+		if (ion_info->ionfd > 0)
+			close(ion_info->ionfd);
+	}
+}
+
+int socket_send_fd(struct socket_info *info)
+{
+	int status;
+	int fd, sockfd;
+	struct socketdata skdata;
+
+	if (!info) {
+		fprintf(stderr, "<%s>: Invalid socket info\n", __func__);
+		return -1;
+	}
+
+	sockfd = info->sockfd;
+	fd = info->datafd;
+	memset(&skdata, 0, sizeof(skdata));
+	skdata.data = fd;
+	skdata.len = sizeof(skdata.data);
+	status = sendtosocket(sockfd, &skdata);
+	if (status < 0) {
+		fprintf(stderr, "<%s>: Failed: sendtosocket\n", __func__);
+		return -1;
+	}
+
+	return 0;
+}
+
+int socket_receive_fd(struct socket_info *info)
+{
+	int status;
+	int fd, sockfd;
+	struct socketdata skdata;
+
+	if (!info) {
+		fprintf(stderr, "<%s>: Invalid socket info\n", __func__);
+		return -1;
+	}
+
+	sockfd = info->sockfd;
+	memset(&skdata, 0, sizeof(skdata));
+	status = receivefromsocket(sockfd, &skdata);
+	if (status < 0) {
+		fprintf(stderr, "<%s>: Failed: receivefromsocket\n", __func__);
+		return -1;
+	}
+
+	fd = (int)skdata.data;
+	info->datafd = fd;
+
+	return status;
+}

tools/testing/selftests/android/ion/ionutils.h

@@ -0,0 +1,55 @@
+#ifndef __ION_UTILS_H
+#define __ION_UTILS_H
+
+#include "ion.h"
+
+#define SOCKET_NAME "ion_socket"
+#define ION_DEVICE "/dev/ion"
+
+#define ION_BUFFER_LEN	4096
+#define MAX_HEAP_COUNT	ION_HEAP_TYPE_CUSTOM
+
+struct socket_info {
+	int sockfd;
+	int datafd;
+	unsigned long buflen;
+};
+
+struct ion_buffer_info {
+	int ionfd;
+	int buffd;
+	unsigned int heap_type;
+	unsigned int flag_type;
+	unsigned long heap_size;
+	unsigned long buflen;
+	unsigned char *buffer;
+};
+
+
+/* This is used to fill the data into the mapped buffer */
+void write_buffer(void *buffer, unsigned long len);
+
+/* This is used to read the data from the exported buffer */
+void read_buffer(void *buffer, unsigned long len);
+
+/* This is used to create an ION buffer FD for the kernel buffer
+ * So you can export this same buffer to others in the form of FD
+ */
+int ion_export_buffer_fd(struct ion_buffer_info *ion_info);
+
+/* This is used to import or map an exported FD.
+ * So we point to same buffer without making a copy. Hence zero-copy.
+ */
+int ion_import_buffer_fd(struct ion_buffer_info *ion_info);
+
+/* This is used to close all references for the ION client */
+void ion_close_buffer_fd(struct ion_buffer_info *ion_info);
+
+/* This is used to send FD to another process using socket IPC */
+int socket_send_fd(struct socket_info *skinfo);
+
+/* This is used to receive FD from another process using socket IPC */
+int socket_receive_fd(struct socket_info *skinfo);
+
+
+#endif

tools/testing/selftests/android/ion/ipcsocket.c

@@ -0,0 +1,227 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <sys/un.h>
+#include <errno.h>
+
+#include "ipcsocket.h"
+
+
+int opensocket(int *sockfd, const char *name, int connecttype)
+{
+	int ret, temp = 1;
+
+	if (!name || strlen(name) > MAX_SOCK_NAME_LEN) {
+		fprintf(stderr, "<%s>: Invalid socket name.\n", __func__);
+		return -1;
+	}
+
+	ret = socket(PF_LOCAL, SOCK_STREAM, 0);
+	if (ret < 0) {
+		fprintf(stderr, "<%s>: Failed socket: <%s>\n",
+			__func__, strerror(errno));
+		return ret;
+	}
+
+	*sockfd = ret;
+	if (setsockopt(*sockfd, SOL_SOCKET, SO_REUSEADDR,
+		(char *)&temp, sizeof(int)) < 0) {
+		fprintf(stderr, "<%s>: Failed setsockopt: <%s>\n",
+		__func__, strerror(errno));
+		goto err;
+	}
+
+	sprintf(sock_name, "/tmp/%s", name);
+
+	if (connecttype == 1) {
+		/* This is for Server connection */
+		struct sockaddr_un skaddr;
+		int clientfd;
+		socklen_t sklen;
+
+		unlink(sock_name);
+		memset(&skaddr, 0, sizeof(skaddr));
+		skaddr.sun_family = AF_LOCAL;
+		strcpy(skaddr.sun_path, sock_name);
+
+		ret = bind(*sockfd, (struct sockaddr *)&skaddr,
+			SUN_LEN(&skaddr));
+		if (ret < 0) {
+			fprintf(stderr, "<%s>: Failed bind: <%s>\n",
+			__func__, strerror(errno));
+			goto err;
+		}
+
+		ret = listen(*sockfd, 5);
+		if (ret < 0) {
+			fprintf(stderr, "<%s>: Failed listen: <%s>\n",
+			__func__, strerror(errno));
+			goto err;
+		}
+
+		memset(&skaddr, 0, sizeof(skaddr));
+		sklen = sizeof(skaddr);
+
+		ret = accept(*sockfd, (struct sockaddr *)&skaddr,
+			(socklen_t *)&sklen);
+		if (ret < 0) {
+			fprintf(stderr, "<%s>: Failed accept: <%s>\n",
+			__func__, strerror(errno));
+			goto err;
+		}
+
+		clientfd = ret;
+		*sockfd = clientfd;
+	} else {
+		/* This is for client connection */
+		struct sockaddr_un skaddr;
+
+		memset(&skaddr, 0, sizeof(skaddr));
+		skaddr.sun_family = AF_LOCAL;
+		strcpy(skaddr.sun_path, sock_name);
+
+		ret = connect(*sockfd, (struct sockaddr *)&skaddr,
+			SUN_LEN(&skaddr));
+		if (ret < 0) {
+			fprintf(stderr, "<%s>: Failed connect: <%s>\n",
+			__func__, strerror(errno));
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	if (*sockfd)
+		close(*sockfd);
+
+	return ret;
+}
+
+int sendtosocket(int sockfd, struct socketdata *skdata)
+{
+	int ret, buffd;
+	unsigned int len;
+	char cmsg_b[CMSG_SPACE(sizeof(int))];
+	struct cmsghdr *cmsg;
+	struct msghdr msgh;
+	struct iovec iov;
+	struct timeval timeout;
+	fd_set selFDs;
+
+	if (!skdata) {
+		fprintf(stderr, "<%s>: socketdata is NULL\n", __func__);
+		return -1;
+	}
+
+	FD_ZERO(&selFDs);
+	FD_SET(0, &selFDs);
+	FD_SET(sockfd, &selFDs);
+	timeout.tv_sec = 20;
+	timeout.tv_usec = 0;
+
+	ret = select(sockfd+1, NULL, &selFDs, NULL, &timeout);
+	if (ret < 0) {
+		fprintf(stderr, "<%s>: Failed select: <%s>\n",
+		__func__, strerror(errno));
+		return -1;
+	}
+
+	if (FD_ISSET(sockfd, &selFDs)) {
+		buffd = skdata->data;
+		len = skdata->len;
+		memset(&msgh, 0, sizeof(msgh));
+		msgh.msg_control = &cmsg_b;
+		msgh.msg_controllen = CMSG_LEN(len);
+		iov.iov_base = "OK";
+		iov.iov_len = 2;
+		msgh.msg_iov = &iov;
+		msgh.msg_iovlen = 1;
+		cmsg = CMSG_FIRSTHDR(&msgh);
+		cmsg->cmsg_level = SOL_SOCKET;
+		cmsg->cmsg_type = SCM_RIGHTS;
+		cmsg->cmsg_len = CMSG_LEN(len);
+		memcpy(CMSG_DATA(cmsg), &buffd, len);
+
+		ret = sendmsg(sockfd, &msgh, MSG_DONTWAIT);
+		if (ret < 0) {
+			fprintf(stderr, "<%s>: Failed sendmsg: <%s>\n",
+			__func__, strerror(errno));
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+int receivefromsocket(int sockfd, struct socketdata *skdata)
+{
+	int ret, buffd;
+	unsigned int len = 0;
+	char cmsg_b[CMSG_SPACE(sizeof(int))];
+	struct cmsghdr *cmsg;
+	struct msghdr msgh;
+	struct iovec iov;
+	fd_set recvFDs;
+	char data[32];
+
+	if (!skdata) {
+		fprintf(stderr, "<%s>: socketdata is NULL\n", __func__);
+		return -1;
+	}
+
+	FD_ZERO(&recvFDs);
+	FD_SET(0, &recvFDs);
+	FD_SET(sockfd, &recvFDs);
+
+	ret = select(sockfd+1, &recvFDs, NULL, NULL, NULL);
+	if (ret < 0) {
+		fprintf(stderr, "<%s>: Failed select: <%s>\n",
+		__func__, strerror(errno));
+		return -1;
+	}
+
+	if (FD_ISSET(sockfd, &recvFDs)) {
+		len = sizeof(buffd);
+		memset(&msgh, 0, sizeof(msgh));
+		msgh.msg_control = &cmsg_b;
+		msgh.msg_controllen = CMSG_LEN(len);
+		iov.iov_base = data;
+		iov.iov_len = sizeof(data)-1;
+		msgh.msg_iov = &iov;
+		msgh.msg_iovlen = 1;
+		cmsg = CMSG_FIRSTHDR(&msgh);
+		cmsg->cmsg_level = SOL_SOCKET;
+		cmsg->cmsg_type = SCM_RIGHTS;
+		cmsg->cmsg_len = CMSG_LEN(len);
+
+		ret = recvmsg(sockfd, &msgh, MSG_DONTWAIT);
+		if (ret < 0) {
+			fprintf(stderr, "<%s>: Failed recvmsg: <%s>\n",
+			__func__, strerror(errno));
+			return -1;
+		}
+
+		memcpy(&buffd, CMSG_DATA(cmsg), len);
+		skdata->data = buffd;
+		skdata->len = len;
+	}
+	return 0;
+}
+
+int closesocket(int sockfd, char *name)
+{
+	char sockname[MAX_SOCK_NAME_LEN];
+
+	if (sockfd)
+		close(sockfd);
+	sprintf(sockname, "/tmp/%s", name);
+	unlink(sockname);
+	shutdown(sockfd, 2);
+
+	return 0;
+}

tools/testing/selftests/android/ion/ipcsocket.h

@@ -0,0 +1,35 @@
+
+#ifndef _IPCSOCKET_H
+#define _IPCSOCKET_H
+
+
+#define MAX_SOCK_NAME_LEN	64
+
+char sock_name[MAX_SOCK_NAME_LEN];
+
+/* This structure is responsible for holding the IPC data
+ * data: hold the buffer fd
+ * len: just the length of 32-bit integer fd
+ */
+struct socketdata {
+	int data;
+	unsigned int len;
+};
+
+/* This API is used to open the IPC socket connection
+ * name: implies a unique socket name in the system
+ * connecttype: implies server(0) or client(1)
+ */
+int opensocket(int *sockfd, const char *name, int connecttype);
+
+/* This is the API to send socket data over IPC socket */
+int sendtosocket(int sockfd, struct socketdata *data);
+
+/* This is the API to receive socket data over IPC socket */
+int receivefromsocket(int sockfd, struct socketdata *data);
+
+/* This is the API to close the socket connection */
+int closesocket(int sockfd, char *name);
+
+
+#endif

tools/testing/selftests/android/run.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+(cd ion; ./ion_test.sh)