include/uapi/linux/android/binder.h

Source file repositories/reference/linux-study-clean/include/uapi/linux/android/binder.h

File Facts

System
Linux kernel
Corpus path
include/uapi/linux/android/binder.h
Extension
.h
Size
17227 bytes
Lines
593
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

struct binder_object_header {
	__u32        type;
};

/*
 * This is the flattened representation of a Binder object for transfer
 * between processes.  The 'offsets' supplied as part of a binder transaction
 * contains offsets into the data where these structures occur.  The Binder
 * driver takes care of re-writing the structure type and data as it moves
 * between processes.
 */
struct flat_binder_object {
	struct binder_object_header	hdr;
	__u32				flags;

	/* 8 bytes of data. */
	union {
		binder_uintptr_t	binder;	/* local object */
		__u32			handle;	/* remote object */
	};

	/* extra data associated with local object */
	binder_uintptr_t	cookie;
};

/**
 * struct binder_fd_object - describes a filedescriptor to be fixed up.
 * @hdr:	common header structure
 * @pad_flags:	padding to remain compatible with old userspace code
 * @pad_binder:	padding to remain compatible with old userspace code
 * @fd:		file descriptor
 * @cookie:	opaque data, used by user-space
 */
struct binder_fd_object {
	struct binder_object_header	hdr;
	__u32				pad_flags;
	union {
		binder_uintptr_t	pad_binder;
		__u32			fd;
	};

	binder_uintptr_t		cookie;
};

/* struct binder_buffer_object - object describing a userspace buffer
 * @hdr:		common header structure
 * @flags:		one or more BINDER_BUFFER_* flags
 * @buffer:		address of the buffer
 * @length:		length of the buffer
 * @parent:		index in offset array pointing to parent buffer
 * @parent_offset:	offset in @parent pointing to this buffer
 *
 * A binder_buffer object represents an object that the
 * binder kernel driver can copy verbatim to the target
 * address space. A buffer itself may be pointed to from
 * within another buffer, meaning that the pointer inside
 * that other buffer needs to be fixed up as well. This
 * can be done by setting the BINDER_BUFFER_FLAG_HAS_PARENT
 * flag in @flags, by setting @parent buffer to the index
 * in the offset array pointing to the parent binder_buffer_object,
 * and by setting @parent_offset to the offset in the parent buffer
 * at which the pointer to this buffer is located.
 */
struct binder_buffer_object {
	struct binder_object_header	hdr;
	__u32				flags;
	binder_uintptr_t		buffer;
	binder_size_t			length;
	binder_size_t			parent;
	binder_size_t			parent_offset;
};

enum {
	BINDER_BUFFER_FLAG_HAS_PARENT = 0x01,
};

/* struct binder_fd_array_object - object describing an array of fds in a buffer
 * @hdr:		common header structure
 * @pad:		padding to ensure correct alignment
 * @num_fds:		number of file descriptors in the buffer
 * @parent:		index in offset array to buffer holding the fd array
 * @parent_offset:	start offset of fd array in the buffer
 *
 * A binder_fd_array object represents an array of file
 * descriptors embedded in a binder_buffer_object. It is
 * different from a regular binder_buffer_object because it
 * describes a list of file descriptors to fix up, not an opaque
 * blob of memory, and hence the kernel needs to treat it differently.
 *
 * An example of how this would be used is with Android's

Annotation

Implementation Notes