[v3,1/5] kernel/pid.c: remove static qualifier from pidfd_create()

Commit Message

Matthew Bobrowski July 21, 2021, 6:17 a.m. UTC

With the idea of returning pidfds from the fanotify API, we need to
expose a mechanism for creating pidfds. We drop the static qualifier
from pidfd_create() and add its declaration to linux/pid.h so that the
pidfd_create() helper can be called from other kernel subsystems
i.e. fanotify.

Signed-off-by: Matthew Bobrowski <[e-mail]>
Acked-by: Christian Brauner <[e-mail]>
---
 include/linux/pid.h | 1 +
 kernel/pid.c        | 4 +++-
 2 files changed, 4 insertions(+), 1 deletion(-)

Patch

diff --git a/include/linux/pid.h b/include/linux/pid.h
index fa10acb8d6a4..af308e15f174 100644
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -78,6 +78,7 @@  struct file;
 
 extern struct pid *pidfd_pid(const struct file *file);
 struct pid *pidfd_get_pid(unsigned int fd, unsigned int *flags);
+int pidfd_create(struct pid *pid, unsigned int flags);
 
 static inline struct pid *get_pid(struct pid *pid)
 {
diff --git a/kernel/pid.c b/kernel/pid.c
index ebdf9c60cd0b..d3cd95b8b080 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -550,10 +550,12 @@  struct pid *pidfd_get_pid(unsigned int fd, unsigned int *flags)
  * Note, that this function can only be called after the fd table has
  * been unshared to avoid leaking the pidfd to the new process.
  *
+ * This symbol should not be explicitly exported to loadable modules.
+ *
  * Return: On success, a cloexec pidfd is returned.
  *         On error, a negative errno number will be returned.
  */
-static int pidfd_create(struct pid *pid, unsigned int flags)
+int pidfd_create(struct pid *pid, unsigned int flags)
 {
 	int fd;