index c116921651948851c74a2cc11a3faa2715c393ee..015c7f7b635d812e137c42fcab69e5e76d1bdd7d 100644 (file)
#include <linux/sched.h>
#include <linux/shrinker.h>
#include <linux/types.h>
+#include <linux/miscdevice.h>
+
+
+
+/**
+ * struct ion_device - the metadata of the ion device node
+ * @dev: the actual misc device
+ * @buffers: an rb tree of all the existing buffers
+ * @buffer_lock: lock protecting the tree of buffers
+ * @lock: rwsem protecting the tree of heaps and clients
+ * @heaps: list of all the heaps in the system
+ * @user_clients: list of all the clients created from userspace
+ */
+struct ion_device {
+ struct miscdevice dev;
+ struct rb_root buffers;
+ struct mutex buffer_lock;
+ struct rw_semaphore lock;
+ struct plist_head heaps;
+ long (*custom_ioctl) (struct ion_client *client, unsigned int cmd,
+ unsigned long arg);
+ struct rb_root clients;
+ struct dentry *debug_root;
+};
+
+/**
+ * struct ion_client - a process/hw block local address space
+ * @node: node in the tree of all clients
+ * @dev: backpointer to ion device
+ * @handles: an rb tree of all the handles in this client
+ * @lock: lock protecting the tree of handles
+ * @name: used for debugging
+ * @task: used for debugging
+ *
+ * A client represents a list of buffers this client may access.
+ * The mutex stored here is used to protect both handles tree
+ * as well as the handles themselves, and should be held while modifying either.
+ */
+struct ion_client {
+ struct rb_node node;
+ struct ion_device *dev;
+ struct rb_root handles;
+ struct mutex lock;
+ const char *name;
+ struct task_struct *task;
+ pid_t pid;
+ struct dentry *debug_root;
+};
+
+/**
+ * ion_handle - a client local reference to a buffer
+ * @ref: reference count
+ * @client: back pointer to the client the buffer resides in
+ * @buffer: pointer to the buffer
+ * @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
+ *
+ * Modifications to node, map_cnt or mapping should be protected by the
+ * lock in the client. Other fields are never changed after initialization.
+ */
+struct ion_handle {
+ struct kref ref;
+ struct ion_client *client;
+ struct ion_buffer *buffer;
+ struct rb_node node;
+ unsigned int kmap_cnt;
+};
+
struct ion_buffer *ion_handle_buffer(struct ion_handle *handle);