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/*
*
* drivers/staging/android/ion/ion.c
*
* Copyright (C) 2011 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/device.h>
#include <linux/err.h>
#include <linux/file.h>
#include <linux/freezer.h>
#include <linux/fs.h>
#include <linux/anon_inodes.h>
#include <linux/kthread.h>
#include <linux/list.h>
#include <linux/memblock.h>
#include <linux/miscdevice.h>
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/mm_types.h>
#include <linux/rbtree.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/debugfs.h>
#include <linux/dma-buf.h>
#include <linux/idr.h>
#include <linux/sched/task.h>
#include "ion.h"
static struct ion_device *internal_dev;
static int heap_id;
bool ion_buffer_cached(struct ion_buffer *buffer)
{
return !!(buffer->flags & ION_FLAG_CACHED);
}
/* this function should only be called while dev->lock is held */
static void ion_buffer_add(struct ion_device *dev,
struct ion_buffer *buffer)
{
struct rb_node **p = &dev->buffers.rb_node;
struct rb_node *parent = NULL;
struct ion_buffer *entry;
while (*p) {
parent = *p;
entry = rb_entry(parent, struct ion_buffer, node);
if (buffer < entry) {
p = &(*p)->rb_left;
} else if (buffer > entry) {
p = &(*p)->rb_right;
} else {
pr_err("%s: buffer already found.", __func__);
BUG();
}
}
rb_link_node(&buffer->node, parent, p);
rb_insert_color(&buffer->node, &dev->buffers);
}
/* 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;
struct sg_table *table;
int ret;
buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
if (!buffer)
return ERR_PTR(-ENOMEM);
buffer->heap = heap;
buffer->flags = flags;
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 == NULL) {
WARN_ONCE(1, "This heap needs to set the sgtable");
ret = -EINVAL;
goto err1;
}
table = buffer->sg_table;
buffer->dev = dev;
buffer->size = len;
buffer->dev = dev;
buffer->size = len;
INIT_LIST_HEAD(&buffer->vmas);
INIT_LIST_HEAD(&buffer->attachments);
mutex_init(&buffer->lock);
mutex_lock(&dev->buffer_lock);
ion_buffer_add(dev, buffer);
mutex_unlock(&dev->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 (WARN_ON(buffer->kmap_cnt > 0))
buffer->heap->ops->unmap_kernel(buffer->heap, buffer);
buffer->heap->ops->free(buffer);
vfree(buffer->pages);
kfree(buffer);
}
static void _ion_buffer_destroy(struct ion_buffer *buffer)
{
struct ion_heap *heap = buffer->heap;
struct ion_device *dev = buffer->dev;
mutex_lock(&dev->buffer_lock);
rb_erase(&buffer->node, &dev->buffers);
mutex_unlock(&dev->buffer_lock);
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 == NULL,
"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->nents, GFP_KERNEL);
if (ret) {
kfree(new_table);
return ERR_PTR(-ENOMEM);
}
new_sg = new_table->sgl;
for_each_sg(table->sgl, sg, table->nents, i) {
memcpy(new_sg, sg, sizeof(*sg));
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 device *dev,
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 = 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_detatch(struct dma_buf *dmabuf,
struct dma_buf_attachment *attachment)
{
struct ion_dma_buf_attachment *a = attachment->priv;
struct ion_buffer *buffer = dmabuf->priv;
free_duped_table(a->table);
mutex_lock(&buffer->lock);
list_del(&a->list);
mutex_unlock(&buffer->lock);
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;
if (!dma_map_sg(attachment->dev, table->sgl, table->nents,
direction)){
ret = -ENOMEM;
goto err;
}
return table;
err:
free_duped_table(table);
return ERR_PTR(ret);
}
static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment,
struct sg_table *table,
enum dma_data_direction direction)
{
dma_unmap_sg(attachment->dev, table->sgl, table->nents, direction);
}
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 void *ion_dma_buf_kmap(struct dma_buf *dmabuf, unsigned long offset)
{
struct ion_buffer *buffer = dmabuf->priv;
return buffer->vaddr + offset * PAGE_SIZE;
}
static void ion_dma_buf_kunmap(struct dma_buf *dmabuf, unsigned long offset,
void *ptr)
{
}
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;
/*
* 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);
mutex_unlock(&buffer->lock);
}
mutex_lock(&buffer->lock);
list_for_each_entry(a, &buffer->attachments, list) {
dma_sync_sg_for_cpu(a->dev, a->table->sgl, a->table->nents,
DMA_BIDIRECTIONAL);
}
mutex_unlock(&buffer->lock);
return 0;
}
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_sg_for_device(a->dev, a->table->sgl, a->table->nents,
DMA_BIDIRECTIONAL);
}
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_detatch,
.begin_cpu_access = ion_dma_buf_begin_cpu_access,
.end_cpu_access = ion_dma_buf_end_cpu_access,
.map_atomic = ion_dma_buf_kmap,
.unmap_atomic = ion_dma_buf_kunmap,
.map = ion_dma_buf_kmap,
.unmap = ion_dma_buf_kunmap,
};
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 == NULL)
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;
}
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;
}
static const struct file_operations ion_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = ion_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = ion_ioctl,
#endif
};
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 dentry *debug_file;
struct ion_device *dev = internal_dev;
if (!heap->ops->allocate || !heap->ops->free)
pr_err("%s: can not add heap with invalid ops struct.\n",
__func__);
spin_lock_init(&heap->free_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)
ion_heap_init_shrinker(heap);
heap->dev = dev;
down_write(&dev->lock);
heap->id = heap_id++;
/*
* use negative heap->id to reverse the priority -- when traversing
* the list later attempt higher id numbers first
*/
plist_node_init(&heap->node, -heap->id);
plist_add(&heap->node, &dev->heaps);
if (heap->shrinker.count_objects && heap->shrinker.scan_objects) {
char debug_name[64];
snprintf(debug_name, 64, "%s_shrink", heap->name);
debug_file = debugfs_create_file(
debug_name, 0644, dev->debug_root, heap,
&debug_shrink_fops);
if (!debug_file) {
char buf[256], *path;
path = dentry_path(dev->debug_root, buf, 256);
pr_err("Failed to create heap shrinker debugfs at %s/%s\n",
path, debug_name);
}
}
dev->heap_cnt++;
up_write(&dev->lock);
}
EXPORT_SYMBOL(ion_device_add_heap);
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);
if (!idev->debug_root) {
pr_err("ion: failed to create debugfs root directory.\n");
goto debugfs_done;
}
debugfs_done:
idev->buffers = RB_ROOT;
mutex_init(&idev->buffer_lock);
init_rwsem(&idev->lock);
plist_head_init(&idev->heaps);
internal_dev = idev;
return 0;
}
subsys_initcall(ion_device_create);
|