include/uapi/linux/pidfd.h

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

File Facts

System
Linux kernel
Corpus path
include/uapi/linux/pidfd.h
Extension
.h
Size
4979 bytes
Lines
125
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 pidfd_info {
	/*
	 * This mask is similar to the request_mask in statx(2).
	 *
	 * Userspace indicates what extensions or expensive-to-calculate fields
	 * they want by setting the corresponding bits in mask. The kernel
	 * will ignore bits that it does not know about.
	 *
	 * When filling the structure, the kernel will only set bits
	 * corresponding to the fields that were actually filled by the kernel.
	 * This also includes any future extensions that might be automatically
	 * filled. If the structure size is too small to contain a field
	 * (requested or not), to avoid confusion the mask will not
	 * contain a bit for that field.
	 *
	 * As such, userspace MUST verify that mask contains the
	 * corresponding flags after the ioctl(2) returns to ensure that it is
	 * using valid data.
	 */
	__u64 mask;
	/*
	 * The information contained in the following fields might be stale at the
	 * time it is received, as the target process might have exited as soon as
	 * the IOCTL was processed, and there is no way to avoid that. However, it
	 * is guaranteed that if the call was successful, then the information was
	 * correct and referred to the intended process at the time the work was
	 * performed. */
	__u64 cgroupid;
	__u32 pid;
	__u32 tgid;
	__u32 ppid;
	__u32 ruid;
	__u32 rgid;
	__u32 euid;
	__u32 egid;
	__u32 suid;
	__u32 sgid;
	__u32 fsuid;
	__u32 fsgid;
	__s32 exit_code;
	struct /* coredump info */ {
		__u32 coredump_mask;
		__u32 coredump_signal;
		__u32 coredump_code;
		__u32 coredump_pad; /* align supported_mask to 8 bytes */
	};
	__u64 supported_mask;	/* Mask flags that this kernel supports */
};

#define PIDFS_IOCTL_MAGIC 0xFF

#define PIDFD_GET_CGROUP_NAMESPACE            _IO(PIDFS_IOCTL_MAGIC, 1)
#define PIDFD_GET_IPC_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 2)
#define PIDFD_GET_MNT_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 3)
#define PIDFD_GET_NET_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 4)
#define PIDFD_GET_PID_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 5)
#define PIDFD_GET_PID_FOR_CHILDREN_NAMESPACE  _IO(PIDFS_IOCTL_MAGIC, 6)
#define PIDFD_GET_TIME_NAMESPACE              _IO(PIDFS_IOCTL_MAGIC, 7)
#define PIDFD_GET_TIME_FOR_CHILDREN_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 8)
#define PIDFD_GET_USER_NAMESPACE              _IO(PIDFS_IOCTL_MAGIC, 9)
#define PIDFD_GET_UTS_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 10)
#define PIDFD_GET_INFO                        _IOWR(PIDFS_IOCTL_MAGIC, 11, struct pidfd_info)

#endif /* _UAPI_LINUX_PIDFD_H */

Annotation

Implementation Notes