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-rw-r--r--kernel/fork.c110
1 files changed, 0 insertions, 110 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 3f22ec90c5c6..662a61f340ce 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1993,116 +1993,6 @@ struct pid *pidfd_pid(const struct file *file)
return ERR_PTR(-EBADF);
}
-static int pidfd_release(struct inode *inode, struct file *file)
-{
- struct pid *pid = file->private_data;
-
- file->private_data = NULL;
- put_pid(pid);
- return 0;
-}
-
-#ifdef CONFIG_PROC_FS
-/**
- * pidfd_show_fdinfo - print information about a pidfd
- * @m: proc fdinfo file
- * @f: file referencing a pidfd
- *
- * Pid:
- * This function will print the pid that a given pidfd refers to in the
- * pid namespace of the procfs instance.
- * If the pid namespace of the process is not a descendant of the pid
- * namespace of the procfs instance 0 will be shown as its pid. This is
- * similar to calling getppid() on a process whose parent is outside of
- * its pid namespace.
- *
- * NSpid:
- * If pid namespaces are supported then this function will also print
- * the pid of a given pidfd refers to for all descendant pid namespaces
- * starting from the current pid namespace of the instance, i.e. the
- * Pid field and the first entry in the NSpid field will be identical.
- * If the pid namespace of the process is not a descendant of the pid
- * namespace of the procfs instance 0 will be shown as its first NSpid
- * entry and no others will be shown.
- * Note that this differs from the Pid and NSpid fields in
- * /proc/<pid>/status where Pid and NSpid are always shown relative to
- * the pid namespace of the procfs instance. The difference becomes
- * obvious when sending around a pidfd between pid namespaces from a
- * different branch of the tree, i.e. where no ancestral relation is
- * present between the pid namespaces:
- * - create two new pid namespaces ns1 and ns2 in the initial pid
- * namespace (also take care to create new mount namespaces in the
- * new pid namespace and mount procfs)
- * - create a process with a pidfd in ns1
- * - send pidfd from ns1 to ns2
- * - read /proc/self/fdinfo/<pidfd> and observe that both Pid and NSpid
- * have exactly one entry, which is 0
- */
-static void pidfd_show_fdinfo(struct seq_file *m, struct file *f)
-{
- struct pid *pid = f->private_data;
- struct pid_namespace *ns;
- pid_t nr = -1;
-
- if (likely(pid_has_task(pid, PIDTYPE_PID))) {
- ns = proc_pid_ns(file_inode(m->file)->i_sb);
- nr = pid_nr_ns(pid, ns);
- }
-
- seq_put_decimal_ll(m, "Pid:\t", nr);
-
-#ifdef CONFIG_PID_NS
- seq_put_decimal_ll(m, "\nNSpid:\t", nr);
- if (nr > 0) {
- int i;
-
- /* If nr is non-zero it means that 'pid' is valid and that
- * ns, i.e. the pid namespace associated with the procfs
- * instance, is in the pid namespace hierarchy of pid.
- * Start at one below the already printed level.
- */
- for (i = ns->level + 1; i <= pid->level; i++)
- seq_put_decimal_ll(m, "\t", pid->numbers[i].nr);
- }
-#endif
- seq_putc(m, '\n');
-}
-#endif
-
-/*
- * Poll support for process exit notification.
- */
-static __poll_t pidfd_poll(struct file *file, struct poll_table_struct *pts)
-{
- struct pid *pid = file->private_data;
- bool thread = file->f_flags & PIDFD_THREAD;
- struct task_struct *task;
- __poll_t poll_flags = 0;
-
- poll_wait(file, &pid->wait_pidfd, pts);
- /*
- * Depending on PIDFD_THREAD, inform pollers when the thread
- * or the whole thread-group exits.
- */
- rcu_read_lock();
- task = pid_task(pid, PIDTYPE_PID);
- if (!task)
- poll_flags = EPOLLIN | EPOLLRDNORM | EPOLLHUP;
- else if (task->exit_state && (thread || thread_group_empty(task)))
- poll_flags = EPOLLIN | EPOLLRDNORM;
- rcu_read_unlock();
-
- return poll_flags;
-}
-
-const struct file_operations pidfd_fops = {
- .release = pidfd_release,
- .poll = pidfd_poll,
-#ifdef CONFIG_PROC_FS
- .show_fdinfo = pidfd_show_fdinfo,
-#endif
-};
-
/**
* __pidfd_prepare - allocate a new pidfd_file and reserve a pidfd
* @pid: the struct pid for which to create a pidfd