[RFC][PATCH 6/7] Define do_fork_with_pids()

[sukadev-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org]

From: Sukadev Bhattiprolu <sukadev-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>

do_fork_with_pids() is same as do_fork(), except that it takes an
additional, target_pids, parameter. This parameter, currently unused,
specifies the target_pids of the process in each of its pid namespaces.

Signed-off-by: Sukadev Bhattiprolu <sukadev-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
---
 include/linux/sched.h |    1 +
 kernel/fork.c         |   17 ++++++++++++++---
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index b4c38bc..2173df1 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1995,6 +1995,7 @@ extern int disallow_signal(int);

 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
+extern long do_fork_with_pids(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *, pid_t *target_pids);
 struct task_struct *fork_idle(int);

 extern void set_task_comm(struct task_struct *tsk, char *from);
diff --git a/kernel/fork.c b/kernel/fork.c
index 373411e..912d008 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1340,17 +1340,17 @@ struct task_struct * __cpuinit fork_idle(int cpu)
  * It copies the process, and if successful kick-starts
  * it and waits for it to finish using the VM if required.
  */
-long do_fork(unsigned long clone_flags,
+long do_fork_with_pids(unsigned long clone_flags,
 	      unsigned long stack_start,
 	      struct pt_regs *regs,
 	      unsigned long stack_size,
 	      int __user *parent_tidptr,
-	      int __user *child_tidptr)
+	      int __user *child_tidptr,
+	      pid_t *target_pids)
 {
 	struct task_struct *p;
 	int trace = 0;
 	long nr;
-	pid_t *target_pids = NULL;

 	/*
 	 * Do some preliminary argument and permissions checking before we
@@ -1448,6 +1448,17 @@ long do_fork(unsigned long clone_flags,
 	return nr;
 }

+long do_fork(unsigned long clone_flags,
+	      unsigned long stack_start,
+	      struct pt_regs *regs,
+	      unsigned long stack_size,
+	      int __user *parent_tidptr,
+	      int __user *child_tidptr)
+{
+	return do_fork_with_pids(clone_flags, stack_start, regs, stack_size,
+			parent_tidptr, child_tidptr, NULL);
+}
+
 #ifndef ARCH_MIN_MMSTRUCT_ALIGN
 #define ARCH_MIN_MMSTRUCT_ALIGN 0
 #endif
-- 
1.5.2.5