[PATCH 3/5] exit: add kernel_waitid_prepare() helper

Jens Axboe
2023-07-11T20:44:13Z

Move the setup logic out of kernel_waitid(), and into a separate helper.

No functional changes intended in this patch.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
kernel/exit.c | 41 +++++++++++++++++++++++++++--------------
1 file changed, 27 insertions(+), 14 deletions(-)

diff --git a/kernel/exit.c b/kernel/exit.c
index d8fb124cc038..8934c91a9fe1 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1662,14 +1662,12 @@ static long do_wait(struct wait_opts *wo)
return retval;
}

-static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
- int options, struct rusage *ru)
+static int kernel_waitid_prepare(struct wait_opts *wo, int which, pid_t upid,
+ struct waitid_info *infop, int options,
+ struct rusage *ru, unsigned int *f_flags)
{
- struct wait_opts wo;
struct pid *pid = NULL;
enum pid_type type;
- long ret;
- unsigned int f_flags = 0;

if (options & ~(WNOHANG|WNOWAIT|WEXITED|WSTOPPED|WCONTINUED|
__WNOTHREAD|__WCLONE|__WALL))
@@ -1703,7 +1701,7 @@ static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
if (upid < 0)
return -EINVAL;

- pid = pidfd_get_pid(upid, &f_flags);
+ pid = pidfd_get_pid(upid, f_flags);
if (IS_ERR(pid))
return PTR_ERR(pid);

@@ -1712,19 +1710,34 @@ static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
return -EINVAL;
}

- wo.wo_type = type;
- wo.wo_pid = pid;
- wo.wo_flags = options;
- wo.wo_info = infop;
- wo.wo_rusage = ru;
- if (f_flags & O_NONBLOCK)
- wo.wo_flags |= WNOHANG;
+ wo->wo_type = type;
+ wo->wo_pid = pid;
+ wo->wo_flags = options;
+ wo->wo_info = infop;
+ wo->wo_rusage = ru;
+ if (*f_flags & O_NONBLOCK)
+ wo->wo_flags |= WNOHANG;
+
+ return 0;
+}
+
+static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
+ int options, struct rusage *ru)
+{
+ struct wait_opts wo;
+ long ret;
+ unsigned int f_flags = 0;
+
+ ret = kernel_waitid_prepare(&wo, which, upid, infop, options, ru,
+ &f_flags);
+ if (ret)
+ return ret;

ret = do_wait(&wo);
if (!ret && !(options & WNOHANG) && (f_flags & O_NONBLOCK))
ret = -EAGAIN;

- put_pid(pid);
+ put_pid(wo.wo_pid);
return ret;
}

--
2.40.1