control: use reference-counted pid
Instead of storing the PID number, take a reference to the task's pid
structure. This protects against duplicates due to PID overflows, and
using pid_vnr() ensures that the PID returned by snd_ctl_elem_info() is
correct as seen from the current namespace.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/control.h b/include/sound/control.h
index 3517745..112374d 100644
--- a/include/sound/control.h
+++ b/include/sound/control.h
@@ -86,10 +86,12 @@
#define snd_kctl_event(n) list_entry(n, struct snd_kctl_event, list)
+struct pid;
+
struct snd_ctl_file {
struct list_head list; /* list of all control files */
struct snd_card *card;
- pid_t pid;
+ struct pid *pid;
int prefer_pcm_subdevice;
int prefer_rawmidi_subdevice;
wait_queue_head_t change_sleep;
