Re: [PATCH v6 4/7] pid: move pidfd_get_pid function to pid.c

process_madvise syscall needs pidfd_get_pid function to translate
pidfd to pid so this patch move the function to kernel/pid.c.

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christian Brauner <christian@brauner.io>
Suggested-by: Alexander Duyck <redacted>
Reviewed-by: Alexander Duyck <redacted>
Signed-off-by: Minchan Kim <minchan@kernel.org>
---
 include/linux/pid.h |  1 +
 kernel/exit.c       | 17 -----------------
 kernel/pid.c        | 17 +++++++++++++++++
 3 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/include/linux/pid.h b/include/linux/pid.h
index 998ae7d24450..993f68cb45c2 100644
--- a/include/linux/pid.h
+++ b/include/linux/pid.h

@@ -75,6 +75,7 @@ extern const struct file_operations pidfd_fops;
 struct file;

 extern struct pid *pidfd_pid(const struct file *file);
+struct pid *pidfd_get_pid(unsigned int fd);

 static inline struct pid *get_pid(struct pid *pid)
 {

diff --git a/kernel/exit.c b/kernel/exit.c
index 0b81b26a872a..43375f9d8bbc 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c

@@ -1470,23 +1470,6 @@ static long do_wait(struct wait_opts *wo)
        return retval;
 }

-static struct pid *pidfd_get_pid(unsigned int fd)
-{
-       struct fd f;
-       struct pid *pid;
-
-       f = fdget(fd);
-       if (!f.file)
-               return ERR_PTR(-EBADF);
-
-       pid = pidfd_pid(f.file);
-       if (!IS_ERR(pid))
-               get_pid(pid);
-
-       fdput(f);
-       return pid;
-}
-
 static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
                          int options, struct rusage *ru)
 {

diff --git a/kernel/pid.c b/kernel/pid.c
index 0f4ecb57214c..360ba480a2a9 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c

@@ -496,6 +496,23 @@ struct pid *find_ge_pid(int nr, struct pid_namespace *ns)
        return idr_get_next(&ns->idr, &nr);
 }

+struct pid *pidfd_get_pid(unsigned int fd)
+{
+       struct fd f;
+       struct pid *pid;
+
+       f = fdget(fd);
+       if (!f.file)
+               return ERR_PTR(-EBADF);
+
+       pid = pidfd_pid(f.file);
+       if (!IS_ERR(pid))
+               get_pid(pid);
+
+       fdput(f);
+       return pid;
+}
+
 /**
  * pidfd_create() - Create a new pid file descriptor.
  *
--

2.25.0.265.gbab2e86ba0-goog