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Diffstat (limited to 'include/uapi/linux/pidfd.h')
-rw-r--r--include/uapi/linux/pidfd.h117
1 files changed, 116 insertions, 1 deletions
diff --git a/include/uapi/linux/pidfd.h b/include/uapi/linux/pidfd.h
index 5406fbc13074..c27a4e238e4b 100644
--- a/include/uapi/linux/pidfd.h
+++ b/include/uapi/linux/pidfd.h
@@ -5,8 +5,123 @@
#include <linux/types.h>
#include <linux/fcntl.h>
+#include <linux/ioctl.h>
/* Flags for pidfd_open(). */
-#define PIDFD_NONBLOCK O_NONBLOCK
+#define PIDFD_NONBLOCK O_NONBLOCK
+#define PIDFD_THREAD O_EXCL
+#ifdef __KERNEL__
+#include <linux/sched.h>
+#define PIDFD_STALE CLONE_PIDFD
+#endif
+
+/* Flags for pidfd_send_signal(). */
+#define PIDFD_SIGNAL_THREAD (1UL << 0)
+#define PIDFD_SIGNAL_THREAD_GROUP (1UL << 1)
+#define PIDFD_SIGNAL_PROCESS_GROUP (1UL << 2)
+
+/* Flags for pidfd_info. */
+#define PIDFD_INFO_PID (1UL << 0) /* Always returned, even if not requested */
+#define PIDFD_INFO_CREDS (1UL << 1) /* Always returned, even if not requested */
+#define PIDFD_INFO_CGROUPID (1UL << 2) /* Always returned if available, even if not requested */
+#define PIDFD_INFO_EXIT (1UL << 3) /* Only returned if requested. */
+#define PIDFD_INFO_COREDUMP (1UL << 4) /* Only returned if requested. */
+
+#define PIDFD_INFO_SIZE_VER0 64 /* sizeof first published struct */
+
+/*
+ * Values for @coredump_mask in pidfd_info.
+ * Only valid if PIDFD_INFO_COREDUMP is set in @mask.
+ *
+ * Note, the @PIDFD_COREDUMP_ROOT flag indicates that the generated
+ * coredump should be treated as sensitive and access should only be
+ * granted to privileged users.
+ */
+#define PIDFD_COREDUMPED (1U << 0) /* Did crash and... */
+#define PIDFD_COREDUMP_SKIP (1U << 1) /* coredumping generation was skipped. */
+#define PIDFD_COREDUMP_USER (1U << 2) /* coredump was done as the user. */
+#define PIDFD_COREDUMP_ROOT (1U << 3) /* coredump was done as root. */
+
+/*
+ * The concept of process and threads in userland and the kernel is a confusing
+ * one - within the kernel every thread is a 'task' with its own individual PID,
+ * however from userland's point of view threads are grouped by a single PID,
+ * which is that of the 'thread group leader', typically the first thread
+ * spawned.
+ *
+ * To cut the Gideon knot, for internal kernel usage, we refer to
+ * PIDFD_SELF_THREAD to refer to the current thread (or task from a kernel
+ * perspective), and PIDFD_SELF_THREAD_GROUP to refer to the current thread
+ * group leader...
+ */
+#define PIDFD_SELF_THREAD -10000 /* Current thread. */
+#define PIDFD_SELF_THREAD_GROUP -20000 /* Current thread group leader. */
+
+/*
+ * ...and for userland we make life simpler - PIDFD_SELF refers to the current
+ * thread, PIDFD_SELF_PROCESS refers to the process thread group leader.
+ *
+ * For nearly all practical uses, a user will want to use PIDFD_SELF.
+ */
+#define PIDFD_SELF PIDFD_SELF_THREAD
+#define PIDFD_SELF_PROCESS PIDFD_SELF_THREAD_GROUP
+
+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;
+ __u32 coredump_mask;
+ __u32 __spare1;
+};
+
+#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 */