[PATCH 006/115] ion: Switch ion to use dma-buf

John Stultz
2013-12-13T22:26:21Z

From: Rebecca Schultz Zavin <rebecca@android.com>

Ion now uses dma-buf file descriptors to share
buffers with userspace. Ion becomes a dma-buf
exporter and any driver that can import dma-bufs
can now import ion file descriptors.

Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
[jstultz: modified patch to apply to staging directory]
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
drivers/staging/android/ion/Kconfig | 1 +
drivers/staging/android/ion/ion.c | 648 +++++++++++++-----------------------
drivers/staging/android/ion/ion.h | 58 +---
3 files changed, 236 insertions(+), 471 deletions(-)

diff --git a/drivers/staging/android/ion/Kconfig b/drivers/staging/android/ion/Kconfig
index 5b48b4e..b5bfdb4 100644
--- a/drivers/staging/android/ion/Kconfig
+++ b/drivers/staging/android/ion/Kconfig
@@ -1,6 +1,7 @@
menuconfig ION
tristate "Ion Memory Manager"
select GENERIC_ALLOCATOR
+ select DMA_SHARED_BUFFER
help
Chose this option to enable the ION Memory Manager.

diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index 3c9ca31..75bf8f2 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -30,6 +30,7 @@
#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/debugfs.h>
+#include <linux/dma-buf.h>

#include "ion.h"
#include "ion_priv.h"
@@ -50,14 +51,12 @@ struct ion_device {
struct rb_root heaps;
long (*custom_ioctl) (struct ion_client *client, unsigned int cmd,
unsigned long arg);
- struct rb_root user_clients;
- struct rb_root kernel_clients;
+ struct rb_root clients;
struct dentry *debug_root;
};

/**
* struct ion_client - a process/hw block local address space
- * @ref: for reference counting the client
* @node: node in the tree of all clients
* @dev: backpointer to ion device
* @handles: an rb tree of all the handles in this client
@@ -71,7 +70,6 @@ struct ion_device {
* as well as the handles themselves, and should be held while modifying either.
*/
struct ion_client {
- struct kref ref;
struct rb_node node;
struct ion_device *dev;
struct rb_root handles;
@@ -91,7 +89,6 @@ struct ion_client {
* @node: node in the client's handle rbtree
* @kmap_cnt: count of times this client has mapped to kernel
* @dmap_cnt: count of times this client has mapped for dma
- * @usermap_cnt: count of times this client has mapped for userspace
*
* Modifications to node, map_cnt or mapping should be protected by the
* lock in the client. Other fields are never changed after initialization.
@@ -102,8 +99,6 @@ struct ion_handle {
struct ion_buffer *buffer;
struct rb_node node;
unsigned int kmap_cnt;
- unsigned int dmap_cnt;
- unsigned int usermap_cnt;
};

/* this function should only be called while dev->lock is held */
@@ -206,17 +201,26 @@ static struct ion_handle *ion_handle_create(struct ion_client *client,
return handle;
}

+static void ion_handle_kmap_put(struct ion_handle *);
+
static void ion_handle_destroy(struct kref *kref)
{
struct ion_handle *handle = container_of(kref, struct ion_handle, ref);
- /* XXX Can a handle be destroyed while it's map count is non-zero?:
- if (handle->map_cnt) unmap
- */
- ion_buffer_put(handle->buffer);
- mutex_lock(&handle->client->lock);
+ struct ion_client *client = handle->client;
+ struct ion_buffer *buffer = handle->buffer;
+
+ mutex_lock(&client->lock);
+
+ mutex_lock(&buffer->lock);
+ while (buffer->kmap_cnt)
+ ion_handle_kmap_put(handle);
+ mutex_unlock(&buffer->lock);
+
if (!RB_EMPTY_NODE(&handle->node))
- rb_erase(&handle->node, &handle->client->handles);
- mutex_unlock(&handle->client->lock);
+ rb_erase(&handle->node, &client->handles);
+ mutex_unlock(&client->lock);
+
+ ion_buffer_put(buffer);
kfree(handle);
}

@@ -362,38 +366,6 @@ void ion_free(struct ion_client *client, struct ion_handle *handle)
ion_handle_put(handle);
}

-static void ion_client_get(struct ion_client *client);
-static int ion_client_put(struct ion_client *client);
-
-static bool _ion_map(int *buffer_cnt, int *handle_cnt)
-{
- bool map;
-
- BUG_ON(*handle_cnt != 0 && *buffer_cnt == 0);
-
- if (*buffer_cnt)
- map = false;
- else
- map = true;
- if (*handle_cnt == 0)
- (*buffer_cnt)++;
- (*handle_cnt)++;
- return map;
-}
-
-static bool _ion_unmap(int *buffer_cnt, int *handle_cnt)
-{
- BUG_ON(*handle_cnt == 0);
- (*handle_cnt)--;
- if (*handle_cnt != 0)
- return false;
- BUG_ON(*buffer_cnt == 0);
- (*buffer_cnt)--;
- if (*buffer_cnt == 0)
- return true;
- return false;
-}
-
int ion_phys(struct ion_client *client, struct ion_handle *handle,
ion_phys_addr_t *addr, size_t *len)
{
@@ -419,175 +391,85 @@ int ion_phys(struct ion_client *client, struct ion_handle *handle,
return ret;
}

-void *ion_map_kernel(struct ion_client *client, struct ion_handle *handle)
+static void *ion_handle_kmap_get(struct ion_handle *handle)
{
- struct ion_buffer *buffer;
+ struct ion_buffer *buffer = handle->buffer;
void *vaddr;

- mutex_lock(&client->lock);
- if (!ion_handle_validate(client, handle)) {
- pr_err("%s: invalid handle passed to map_kernel.\n",
- __func__);
- mutex_unlock(&client->lock);
- return ERR_PTR(-EINVAL);
+ if (handle->kmap_cnt) {
+ handle->kmap_cnt++;
+ return buffer->vaddr;
+ } else if (buffer->kmap_cnt) {
+ handle->kmap_cnt++;
+ buffer->kmap_cnt++;
+ return buffer->vaddr;
}

- buffer = handle->buffer;
- mutex_lock(&buffer->lock);
-
- if (!handle->buffer->heap->ops->map_kernel) {
- pr_err("%s: map_kernel is not implemented by this heap.\n",
- __func__);
- mutex_unlock(&buffer->lock);
- mutex_unlock(&client->lock);
- return ERR_PTR(-ENODEV);
+ vaddr = buffer->heap->ops->map_kernel(buffer->heap, buffer);
+ buffer->vaddr = vaddr;
+ if (IS_ERR_OR_NULL(vaddr)) {
+ buffer->vaddr = NULL;
+ return vaddr;
}
+ handle->kmap_cnt++;
+ buffer->kmap_cnt++;
+ return vaddr;
+}

- if (_ion_map(&buffer->kmap_cnt, &handle->kmap_cnt)) {
- vaddr = buffer->heap->ops->map_kernel(buffer->heap, buffer);
- if (IS_ERR_OR_NULL(vaddr))
- _ion_unmap(&buffer->kmap_cnt, &handle->kmap_cnt);
- buffer->vaddr = vaddr;
- } else {
- vaddr = buffer->vaddr;
+static void ion_handle_kmap_put(struct ion_handle *handle)
+{
+ struct ion_buffer *buffer = handle->buffer;
+
+ handle->kmap_cnt--;
+ if (!handle->kmap_cnt)
+ buffer->kmap_cnt--;
+ if (!buffer->kmap_cnt) {
+ buffer->heap->ops->unmap_kernel(buffer->heap, buffer);
+ buffer->vaddr = NULL;
}
- mutex_unlock(&buffer->lock);
- mutex_unlock(&client->lock);
- return vaddr;
}

-struct sg_table *ion_map_dma(struct ion_client *client,
- struct ion_handle *handle)
+void *ion_map_kernel(struct ion_client *client, struct ion_handle *handle)
{
struct ion_buffer *buffer;
- struct sg_table *table;
+ void *vaddr;

mutex_lock(&client->lock);
if (!ion_handle_validate(client, handle)) {
- pr_err("%s: invalid handle passed to map_dma.\n",
+ pr_err("%s: invalid handle passed to map_kernel.\n",
__func__);
mutex_unlock(&client->lock);
return ERR_PTR(-EINVAL);
}
+
buffer = handle->buffer;
- mutex_lock(&buffer->lock);

- if (!handle->buffer->heap->ops->map_dma) {
+ if (!handle->buffer->heap->ops->map_kernel) {
pr_err("%s: map_kernel is not implemented by this heap.\n",
__func__);
- mutex_unlock(&buffer->lock);
mutex_unlock(&client->lock);
return ERR_PTR(-ENODEV);
}
- if (_ion_map(&buffer->dmap_cnt, &handle->dmap_cnt)) {
- table = buffer->heap->ops->map_dma(buffer->heap, buffer);
- if (IS_ERR_OR_NULL(table))
- _ion_unmap(&buffer->dmap_cnt, &handle->dmap_cnt);
- buffer->sg_table = table;
- } else {
- table = buffer->sg_table;
- }
- mutex_unlock(&buffer->lock);
- mutex_unlock(&client->lock);
- return table;
-}
-
-void ion_unmap_kernel(struct ion_client *client, struct ion_handle *handle)
-{
- struct ion_buffer *buffer;

- mutex_lock(&client->lock);
- buffer = handle->buffer;
mutex_lock(&buffer->lock);
- if (_ion_unmap(&buffer->kmap_cnt, &handle->kmap_cnt)) {
- buffer->heap->ops->unmap_kernel(buffer->heap, buffer);
- buffer->vaddr = NULL;
- }
+ vaddr = ion_handle_kmap_get(handle);
mutex_unlock(&buffer->lock);
mutex_unlock(&client->lock);
+ return vaddr;
}

-void ion_unmap_dma(struct ion_client *client, struct ion_handle *handle)
+void ion_unmap_kernel(struct ion_client *client, struct ion_handle *handle)
{
struct ion_buffer *buffer;

mutex_lock(&client->lock);
buffer = handle->buffer;
mutex_lock(&buffer->lock);
- if (_ion_unmap(&buffer->dmap_cnt, &handle->dmap_cnt)) {
- buffer->heap->ops->unmap_dma(buffer->heap, buffer);
- buffer->sg_table = NULL;
- }
+ ion_handle_kmap_put(handle);
mutex_unlock(&buffer->lock);
mutex_unlock(&client->lock);
}

-
-struct ion_buffer *ion_share(struct ion_client *client,
- struct ion_handle *handle)
-{
- bool valid_handle;
-
- mutex_lock(&client->lock);
- valid_handle = ion_handle_validate(client, handle);
- mutex_unlock(&client->lock);
- if (!valid_handle) {
- WARN("%s: invalid handle passed to share.\n", __func__);
- return ERR_PTR(-EINVAL);
- }
-
- /* do not take an extra reference here, the burden is on the caller
- * to make sure the buffer doesn't go away while it's passing it
- * to another client -- ion_free should not be called on this handle
- * until the buffer has been imported into the other client
- */
- return handle->buffer;
-}
-
-struct ion_handle *ion_import(struct ion_client *client,
- struct ion_buffer *buffer)
-{
- struct ion_handle *handle = NULL;
-
- mutex_lock(&client->lock);
- /* if a handle exists for this buffer just take a reference to it */
- handle = ion_handle_lookup(client, buffer);
- if (!IS_ERR_OR_NULL(handle)) {
- ion_handle_get(handle);
- goto end;
- }
- handle = ion_handle_create(client, buffer);
- if (IS_ERR_OR_NULL(handle))
- goto end;
- ion_handle_add(client, handle);
-end:
- mutex_unlock(&client->lock);
- return handle;
-}
-
-static const struct file_operations ion_share_fops;
-
-struct ion_handle *ion_import_fd(struct ion_client *client, int fd)
-{
- struct file *file = fget(fd);
- struct ion_handle *handle;
-
- if (!file) {
- pr_err("%s: imported fd not found in file table.\n", __func__);
- return ERR_PTR(-EINVAL);
- }
- if (file->f_op != &ion_share_fops) {
- pr_err("%s: imported file is not a shared ion file.\n",
- __func__);
- handle = ERR_PTR(-EINVAL);
- goto end;
- }
- handle = ion_import(client, file->private_data);
-end:
- fput(file);
- return handle;
-}
-
static int ion_debug_client_show(struct seq_file *s, void *unused)
{
struct ion_client *client = s->private;
@@ -612,8 +494,7 @@ static int ion_debug_client_show(struct seq_file *s, void *unused)
for (i = 0; i < ION_NUM_HEAPS; i++) {
if (!names[i])
continue;
- seq_printf(s, "%16.16s: %16u %d\n", names[i], sizes[i],
- atomic_read(&client->ref.refcount));
+ seq_printf(s, "%16.16s: %16u\n", names[i], sizes[i]);
}
return 0;
}
@@ -630,29 +511,6 @@ static const struct file_operations debug_client_fops = {
.release = single_release,
};

-static struct ion_client *ion_client_lookup(struct ion_device *dev,
- struct task_struct *task)
-{
- struct rb_node *n = dev->user_clients.rb_node;
- struct ion_client *client;
-
- mutex_lock(&dev->lock);
- while (n) {
- client = rb_entry(n, struct ion_client, node);
- if (task == client->task) {
- ion_client_get(client);
- mutex_unlock(&dev->lock);
- return client;
- } else if (task < client->task) {
- n = n->rb_left;
- } else if (task > client->task) {
- n = n->rb_right;
- }
- }
- mutex_unlock(&dev->lock);
- return NULL;
-}
-
struct ion_client *ion_client_create(struct ion_device *dev,
unsigned int heap_mask,
const char *name)
@@ -678,16 +536,6 @@ struct ion_client *ion_client_create(struct ion_device *dev,
}
task_unlock(current->group_leader);

- /* if this isn't a kernel thread, see if a client already
- exists */
- if (task) {
- client = ion_client_lookup(dev, task);
- if (!IS_ERR_OR_NULL(client)) {
- put_task_struct(current->group_leader);
- return client;
- }
- }
-
client = kzalloc(sizeof(struct ion_client), GFP_KERNEL);
if (!client) {
if (task)
@@ -702,36 +550,20 @@ struct ion_client *ion_client_create(struct ion_device *dev,
client->heap_mask = heap_mask;
client->task = task;
client->pid = pid;
- kref_init(&client->ref);

mutex_lock(&dev->lock);
- if (task) {
- p = &dev->user_clients.rb_node;
- while (*p) {
- parent = *p;
- entry = rb_entry(parent, struct ion_client, node);
-
- if (task < entry->task)
- p = &(*p)->rb_left;
- else if (task > entry->task)
- p = &(*p)->rb_right;
- }
- rb_link_node(&client->node, parent, p);
- rb_insert_color(&client->node, &dev->user_clients);
- } else {
- p = &dev->kernel_clients.rb_node;
- while (*p) {
- parent = *p;
- entry = rb_entry(parent, struct ion_client, node);
-
- if (client < entry)
- p = &(*p)->rb_left;
- else if (client > entry)
- p = &(*p)->rb_right;
- }
- rb_link_node(&client->node, parent, p);
- rb_insert_color(&client->node, &dev->kernel_clients);
+ p = &dev->clients.rb_node;
+ while (*p) {
+ parent = *p;
+ entry = rb_entry(parent, struct ion_client, node);
+
+ if (client < entry)
+ p = &(*p)->rb_left;
+ else if (client > entry)
+ p = &(*p)->rb_right;
}
+ rb_link_node(&client->node, parent, p);
+ rb_insert_color(&client->node, &dev->clients);

snprintf(debug_name, 64, "%u", client->pid);
client->debug_root = debugfs_create_file(debug_name, 0664,
@@ -742,9 +574,8 @@ struct ion_client *ion_client_create(struct ion_device *dev,
return client;
}

-static void _ion_client_destroy(struct kref *kref)
+void ion_client_destroy(struct ion_client *client)
{
- struct ion_client *client = container_of(kref, struct ion_client, ref);
struct ion_device *dev = client->dev;
struct rb_node *n;

@@ -755,204 +586,192 @@ static void _ion_client_destroy(struct kref *kref)
ion_handle_destroy(&handle->ref);
}
mutex_lock(&dev->lock);
- if (client->task) {
- rb_erase(&client->node, &dev->user_clients);
+ if (client->task)
put_task_struct(client->task);
- } else {
- rb_erase(&client->node, &dev->kernel_clients);
- }
+ rb_erase(&client->node, &dev->clients);
debugfs_remove_recursive(client->debug_root);
mutex_unlock(&dev->lock);

kfree(client);
}

-static void ion_client_get(struct ion_client *client)
-{
- kref_get(&client->ref);
-}
-
-static int ion_client_put(struct ion_client *client)
-{
- return kref_put(&client->ref, _ion_client_destroy);
-}
-
-void ion_client_destroy(struct ion_client *client)
-{
- ion_client_put(client);
-}
-
-static int ion_share_release(struct inode *inode, struct file* file)
-{
- struct ion_buffer *buffer = file->private_data;
-
- pr_debug("%s: %d\n", __func__, __LINE__);
- /* drop the reference to the buffer -- this prevents the
- buffer from going away because the client holding it exited
- while it was being passed */
- ion_buffer_put(buffer);
- return 0;
-}
-
-static void ion_vma_open(struct vm_area_struct *vma)
+static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment,
+ enum dma_data_direction direction)
{
+ struct dma_buf *dmabuf = attachment->dmabuf;
+ struct ion_buffer *buffer = dmabuf->priv;
+ struct sg_table *table;

- struct ion_buffer *buffer = vma->vm_file->private_data;
- struct ion_handle *handle = vma->vm_private_data;
- struct ion_client *client;
+ mutex_lock(&buffer->lock);

- pr_debug("%s: %d\n", __func__, __LINE__);
- /* check that the client still exists and take a reference so
- it can't go away until this vma is closed */
- client = ion_client_lookup(buffer->dev, current->group_leader);
- if (IS_ERR_OR_NULL(client)) {
- vma->vm_private_data = NULL;
- return;
+ if (!buffer->heap->ops->map_dma) {
+ pr_err("%s: map_dma is not implemented by this heap.\n",
+ __func__);
+ mutex_unlock(&buffer->lock);
+ return ERR_PTR(-ENODEV);
}
-
- if (!ion_handle_validate(client, handle)) {
- ion_client_put(client);
- vma->vm_private_data = NULL;
- return;
+ /* if an sg list already exists for this buffer just return it */
+ if (buffer->dmap_cnt) {
+ table = buffer->sg_table;
+ goto end;
}

- ion_handle_get(handle);
-
- pr_debug("%s: %d client_cnt %d handle_cnt %d alloc_cnt %d\n",
- __func__, __LINE__,
- atomic_read(&client->ref.refcount),
- atomic_read(&handle->ref.refcount),
- atomic_read(&buffer->ref.refcount));
+ /* otherwise call into the heap to create one */
+ table = buffer->heap->ops->map_dma(buffer->heap, buffer);
+ if (IS_ERR_OR_NULL(table))
+ goto err;
+ buffer->sg_table = table;
+end:
+ buffer->dmap_cnt++;
+err:
+ mutex_unlock(&buffer->lock);
+ return table;
}

-static void ion_vma_close(struct vm_area_struct *vma)
+static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment,
+ struct sg_table *table,
+ enum dma_data_direction direction)
{
- struct ion_handle *handle = vma->vm_private_data;
- struct ion_buffer *buffer = vma->vm_file->private_data;
- struct ion_client *client;
+ struct dma_buf *dmabuf = attachment->dmabuf;
+ struct ion_buffer *buffer = dmabuf->priv;

- pr_debug("%s: %d\n", __func__, __LINE__);
- /* this indicates the client is gone, nothing to do here */
- if (!handle)
- return;
- client = handle->client;
- pr_debug("%s: %d client_cnt %d handle_cnt %d alloc_cnt %d\n",
- __func__, __LINE__,
- atomic_read(&client->ref.refcount),
- atomic_read(&handle->ref.refcount),
- atomic_read(&buffer->ref.refcount));
- ion_handle_put(handle);
- ion_client_put(client);
- pr_debug("%s: %d client_cnt %d handle_cnt %d alloc_cnt %d\n",
- __func__, __LINE__,
- atomic_read(&client->ref.refcount),
- atomic_read(&handle->ref.refcount),
- atomic_read(&buffer->ref.refcount));
+ mutex_lock(&buffer->lock);
+ buffer->dmap_cnt--;
+ if (!buffer->dmap_cnt) {
+ buffer->heap->ops->unmap_dma(buffer->heap, buffer);
+ buffer->sg_table = NULL;
+ }
+ mutex_unlock(&buffer->lock);
}

-static struct vm_operations_struct ion_vm_ops = {
- .open = ion_vma_open,
- .close = ion_vma_close,
-};
-
-static int ion_share_mmap(struct file *file, struct vm_area_struct *vma)
+static int ion_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
{
- struct ion_buffer *buffer = file->private_data;
- unsigned long size = vma->vm_end - vma->vm_start;
- struct ion_client *client;
- struct ion_handle *handle;
+ struct ion_buffer *buffer = dmabuf->priv;
int ret;

- pr_debug("%s: %d\n", __func__, __LINE__);
- /* make sure the client still exists, it's possible for the client to
- have gone away but the map/share fd still to be around, take
- a reference to it so it can't go away while this mapping exists */
- client = ion_client_lookup(buffer->dev, current->group_leader);
- if (IS_ERR_OR_NULL(client)) {
- pr_err("%s: trying to mmap an ion handle in a process with no "
- "ion client\n", __func__);
- return -EINVAL;
- }
-
- if ((size > buffer->size) || (size + (vma->vm_pgoff << PAGE_SHIFT) >
- buffer->size)) {
- pr_err("%s: trying to map larger area than handle has available"
- "\n", __func__);
- ret = -EINVAL;
- goto err;
- }
-
- /* find the handle and take a reference to it */
- handle = ion_import(client, buffer);
- if (IS_ERR_OR_NULL(handle)) {
- ret = -EINVAL;
- goto err;
- }
-
- if (!handle->buffer->heap->ops->map_user) {
+ if (!buffer->heap->ops->map_user) {
pr_err("%s: this heap does not define a method for mapping "
"to userspace\n", __func__);
- ret = -EINVAL;
- goto err1;
+ return -EINVAL;
}

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) {
+
+ if (ret)
pr_err("%s: failure mapping buffer to userspace\n",
__func__);
- goto err1;
- }

- vma->vm_ops = &ion_vm_ops;
- /* move the handle into the vm_private_data so we can access it from
- vma_open/close */
- vma->vm_private_data = handle;
- pr_debug("%s: %d client_cnt %d handle_cnt %d alloc_cnt %d\n",
- __func__, __LINE__,
- atomic_read(&client->ref.refcount),
- atomic_read(&handle->ref.refcount),
- atomic_read(&buffer->ref.refcount));
- return 0;
-
-err1:
- /* drop the reference to the handle */
- ion_handle_put(handle);
-err:
- /* drop the reference to the client */
- ion_client_put(client);
return ret;
}

-static const struct file_operations ion_share_fops = {
- .owner = THIS_MODULE,
- .release = ion_share_release,
- .mmap = ion_share_mmap,
-};
+static void ion_dma_buf_release(struct dma_buf *dmabuf)
+{
+ struct ion_buffer *buffer = dmabuf->priv;
+ ion_buffer_put(buffer);
+}

-static int ion_ioctl_share(struct file *parent, struct ion_client *client,
- struct ion_handle *handle)
+static void *ion_dma_buf_kmap(struct dma_buf *dmabuf, unsigned long offset)
{
- int fd = get_unused_fd();
- struct file *file;
+ return NULL;
+}

- if (fd < 0)
- return fd;
+static void ion_dma_buf_kunmap(struct dma_buf *dmabuf, unsigned long offset,
+ void *ptr)
+{
+ return;
+}
+
+static void *ion_dma_buf_kmap_atomic(struct dma_buf *dmabuf,
+ unsigned long offset)
+{
+ return NULL;
+}
+
+static void ion_dma_buf_kunmap_atomic(struct dma_buf *dmabuf,
+ unsigned long offset, void *ptr)
+{
+ return;
+}

- file = anon_inode_getfile("ion_share_fd", &ion_share_fops,
- handle->buffer, O_RDWR);
- if (IS_ERR_OR_NULL(file))
- goto err;
- ion_buffer_get(handle->buffer);
- fd_install(fd, file);

+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,
+ .kmap_atomic = ion_dma_buf_kmap_atomic,
+ .kunmap_atomic = ion_dma_buf_kunmap_atomic,
+ .kmap = ion_dma_buf_kmap,
+ .kunmap = ion_dma_buf_kunmap,
+};
+
+int ion_share_dma_buf(struct ion_client *client, struct ion_handle *handle)
+{
+ struct ion_buffer *buffer;
+ struct dma_buf *dmabuf;
+ bool valid_handle;
+ int fd;
+
+ mutex_lock(&client->lock);
+ valid_handle = ion_handle_validate(client, handle);
+ mutex_unlock(&client->lock);
+ if (!valid_handle) {
+ WARN("%s: invalid handle passed to share.\n", __func__);
+ return -EINVAL;
+ }
+
+ buffer = handle->buffer;
+ ion_buffer_get(buffer);
+ dmabuf = dma_buf_export(buffer, &dma_buf_ops, buffer->size, O_RDWR);
+ if (IS_ERR(dmabuf)) {
+ ion_buffer_put(buffer);
+ return PTR_ERR(dmabuf);
+ }
+ fd = dma_buf_fd(dmabuf, O_CLOEXEC);
+ if (fd < 0) {
+ dma_buf_put(dmabuf);
+ ion_buffer_put(buffer);
+ }
return fd;
+}

-err:
- put_unused_fd(fd);
- return -ENFILE;
+struct ion_handle *ion_import_dma_buf(struct ion_client *client, int fd)
+{
+ struct dma_buf *dmabuf;
+ struct ion_buffer *buffer;
+ struct ion_handle *handle;
+
+ dmabuf = dma_buf_get(fd);
+ if (IS_ERR_OR_NULL(dmabuf))
+ return ERR_PTR(PTR_ERR(dmabuf));
+ /* if this memory came from ion */
+
+ if (dmabuf->ops != &dma_buf_ops) {
+ pr_err("%s: can not import dmabuf from another exporter\n",
+ __func__);
+ dma_buf_put(dmabuf);
+ return ERR_PTR(-EINVAL);
+ }
+ buffer = dmabuf->priv;
+
+ mutex_lock(&client->lock);
+ /* if a handle exists for this buffer just take a reference to it */
+ handle = ion_handle_lookup(client, buffer);
+ if (!IS_ERR_OR_NULL(handle)) {
+ ion_handle_get(handle);
+ goto end;
+ }
+ handle = ion_handle_create(client, buffer);
+ if (IS_ERR_OR_NULL(handle))
+ goto end;
+ ion_handle_add(client, handle);
+end:
+ mutex_unlock(&client->lock);
+ dma_buf_put(dmabuf);
+ return handle;
}

static long ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
@@ -994,22 +813,13 @@ static long ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
ion_free(client, data.handle);
break;
}
- case ION_IOC_MAP:
case ION_IOC_SHARE:
{
struct ion_fd_data data;

if (copy_from_user(&data, (void __user *)arg, sizeof(data)))
return -EFAULT;
- mutex_lock(&client->lock);
- if (!ion_handle_validate(client, data.handle)) {
- pr_err("%s: invalid handle passed to share ioctl.\n",
- __func__);
- mutex_unlock(&client->lock);
- return -EINVAL;
- }
- data.fd = ion_ioctl_share(filp, client, data.handle);
- mutex_unlock(&client->lock);
+ data.fd = ion_share_dma_buf(client, data.handle);
if (copy_to_user((void __user *)arg, &data, sizeof(data)))
return -EFAULT;
break;
@@ -1020,8 +830,7 @@ static long ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
if (copy_from_user(&data, (void __user *)arg,
sizeof(struct ion_fd_data)))
return -EFAULT;
-
- data.handle = ion_import_fd(client, data.fd);
+ data.handle = ion_import_dma_buf(client, data.fd);
if (IS_ERR(data.handle))
data.handle = NULL;
if (copy_to_user((void __user *)arg, &data,
@@ -1052,7 +861,7 @@ static int ion_release(struct inode *inode, struct file *file)
struct ion_client *client = file->private_data;

pr_debug("%s: %d\n", __func__, __LINE__);
- ion_client_put(client);
+ ion_client_destroy(client);
return 0;
}

@@ -1103,27 +912,23 @@ static int ion_debug_heap_show(struct seq_file *s, void *unused)
struct rb_node *n;

seq_printf(s, "%16.s %16.s %16.s\n", "client", "pid", "size");
- for (n = rb_first(&dev->user_clients); n; n = rb_next(n)) {
- struct ion_client *client = rb_entry(n, struct ion_client,
- node);
- char task_comm[TASK_COMM_LEN];
- size_t size = ion_debug_heap_total(client, heap->type);
- if (!size)
- continue;

- get_task_comm(task_comm, client->task);
- seq_printf(s, "%16.s %16u %16u\n", task_comm, client->pid,
- size);
- }
-
- for (n = rb_first(&dev->kernel_clients); n; n = rb_next(n)) {
+ for (n = rb_first(&dev->clients); n; n = rb_next(n)) {
struct ion_client *client = rb_entry(n, struct ion_client,
node);
size_t size = ion_debug_heap_total(client, heap->type);
if (!size)
continue;
- seq_printf(s, "%16.s %16u %16u\n", client->name, client->pid,
- size);
+ if (client->task) {
+ char task_comm[TASK_COMM_LEN];
+
+ get_task_comm(task_comm, client->task);
+ seq_printf(s, "%16.s %16u %16u\n", task_comm,
+ client->pid, size);
+ } else {
+ seq_printf(s, "%16.s %16u %16u\n", client->name,
+ client->pid, size);
+ }
}
return 0;
}
@@ -1201,8 +1006,7 @@ struct ion_device *ion_device_create(long (*custom_ioctl)
idev->buffers = RB_ROOT;
mutex_init(&idev->lock);
idev->heaps = RB_ROOT;
- idev->user_clients = RB_ROOT;
- idev->kernel_clients = RB_ROOT;
+ idev->clients = RB_ROOT;
return idev;
}

diff --git a/drivers/staging/android/ion/ion.h b/drivers/staging/android/ion/ion.h
index 4e012b8..84ca2a9 100644
--- a/drivers/staging/android/ion/ion.h
+++ b/drivers/staging/android/ion/ion.h
@@ -176,63 +176,23 @@ void *ion_map_kernel(struct ion_client *client, struct ion_handle *handle);
void ion_unmap_kernel(struct ion_client *client, struct ion_handle *handle);

/**
- * ion_map_dma - create a dma mapping for a given handle
+ * ion_share_dma_buf() - given an ion client, create a dma-buf fd
* @client: the client
- * @handle: handle to map
- *
- * Return an sg_table describing the given handle
- */
-struct sg_table *ion_map_dma(struct ion_client *client,
- struct ion_handle *handle);
-
-/**
- * ion_unmap_dma() - destroy a dma mapping for a handle
- * @client: the client
- * @handle: handle to unmap
+ * @handle: the handle
*/
-void ion_unmap_dma(struct ion_client *client, struct ion_handle *handle);
+int ion_share_dma_buf(struct ion_client *client, struct ion_handle *handle);

/**
- * ion_share() - given a handle, obtain a buffer to pass to other clients
+ * ion_import_dma_buf() - given an dma-buf fd from the ion exporter get handle
* @client: the client
- * @handle: the handle to share
+ * @fd: the dma-buf fd
*
- * Given a handle, return a buffer, which exists in a global name
- * space, and can be passed to other clients. Should be passed into ion_import
- * to obtain a new handle for this buffer.
- *
- * NOTE: This function does do not an extra reference. The burden is on the
- * caller to make sure the buffer doesn't go away while it's being passed to
- * another client. That is, ion_free should not be called on this handle until
- * the buffer has been imported into the other client.
- */
-struct ion_buffer *ion_share(struct ion_client *client,
- struct ion_handle *handle);
-
-/**
- * ion_import() - given an buffer in another client, import it
- * @client: this blocks client
- * @buffer: the buffer to import (as obtained from ion_share)
- *
- * Given a buffer, add it to the client and return the handle to use to refer
- * to it further. This is called to share a handle from one kernel client to
- * another.
+ * Given an dma-buf fd that was allocated through ion via ion_share_dma_buf,
+ * import that fd and return a handle representing it. If a dma-buf from
+ * another exporter is passed in this function will return ERR_PTR(-EINVAL)
*/
-struct ion_handle *ion_import(struct ion_client *client,
- struct ion_buffer *buffer);
+struct ion_handle *ion_import_dma_buf(struct ion_client *client, int fd);

-/**
- * ion_import_fd() - given an fd obtained via ION_IOC_SHARE ioctl, import it
- * @client: this blocks client
- * @fd: the fd
- *
- * A helper function for drivers that will be recieving ion buffers shared
- * with them from userspace. These buffers are represented by a file
- * descriptor obtained as the return from the ION_IOC_SHARE ioctl.
- * This function coverts that fd into the underlying buffer, and returns
- * the handle to use to refer to it further.
- */
-struct ion_handle *ion_import_fd(struct ion_client *client, int fd);
#endif /* __KERNEL__ */

/**
--
1.8.3.2