fork: allow kernel code to call copy_process

The next patch adds helpers like create_io_thread, but for use by the
vhost layer. There are several functions, so they are in their own file
instead of cluttering up fork.c. This patch allows that new file to
call copy_process.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>

include/linux/sched/task.h

@@ -93,6 +93,8 @@ extern void exit_files(struct task_struct *);
 extern void exit_itimers(struct task_struct *);
 
 extern pid_t kernel_clone(struct kernel_clone_args *kargs);
+struct task_struct *copy_process(struct pid *pid, int trace, int node,
+				 struct kernel_clone_args *args);
 struct task_struct *create_io_thread(int (*fn)(void *), void *arg, int node);
 struct task_struct *fork_idle(int);
 extern pid_t kernel_thread(int (*fn)(void *), void *arg, const char *name,

kernel/fork.c

@@ -2016,7 +2016,7 @@ static void rv_task_fork(struct task_struct *p)
  * parts of the process environment (as per the clone
  * flags). The actual kick-off is left to the caller.
  */
-static __latent_entropy struct task_struct *copy_process(
+__latent_entropy struct task_struct *copy_process(
 					struct pid *pid,
 					int trace,
 					int node,