exit: support non-blocking pidfds

[linux-2.6-microblaze.git] / kernel / exit.c

diff --git a/kernel/exit.c b/kernel/exit.c
index 733e80f..1f51c27 100644 (file)
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1474,7 +1474,7 @@ end:
        return retval;
 }
 
-static struct pid *pidfd_get_pid(unsigned int fd)
+static struct pid *pidfd_get_pid(unsigned int fd, unsigned int *flags)
 {
        struct fd f;
        struct pid *pid;
@@ -1484,8 +1484,10 @@ static struct pid *pidfd_get_pid(unsigned int fd)
                return ERR_PTR(-EBADF);
 
        pid = pidfd_pid(f.file);
-       if (!IS_ERR(pid))
+       if (!IS_ERR(pid)) {
                get_pid(pid);
+               *flags = f.file->f_flags;
+       }
 
        fdput(f);
        return pid;
@@ -1498,6 +1500,7 @@ static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
        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))
@@ -1531,9 +1534,10 @@ static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
                if (upid < 0)
                        return -EINVAL;
 
-               pid = pidfd_get_pid(upid);
+               pid = pidfd_get_pid(upid, &f_flags);
                if (IS_ERR(pid))
                        return PTR_ERR(pid);
+
                break;
        default:
                return -EINVAL;
@@ -1544,7 +1548,12 @@ static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
        wo.wo_flags     = options;
        wo.wo_info      = infop;
        wo.wo_rusage    = ru;
+       if (f_flags & O_NONBLOCK)
+               wo.wo_flags |= WNOHANG;
+
        ret = do_wait(&wo);
+       if (!ret && !(options & WNOHANG) && (f_flags & O_NONBLOCK))
+               ret = -EAGAIN;
 
        put_pid(pid);
        return ret;