From 99bca5d776a3011214041c42107a210fe315a35e Mon Sep 17 00:00:00 2001 From: Elizabeth Figura Date: Sun, 19 May 2024 15:24:35 -0500 Subject: ntsync: Introduce NTSYNC_IOC_EVENT_PULSE. This corresponds to the NT syscall NtPulseEvent(). This wakes up any waiters as if the event had been set, but does not set the event, instead resetting it if it had been signalled. Thus, for a manual-reset event, all waiters are woken, whereas for an auto-reset event, at most one waiter is woken. Signed-off-by: Elizabeth Figura --- drivers/misc/ntsync.c | 8 ++++++-- include/uapi/linux/ntsync.h | 1 + 2 files changed, 7 insertions(+), 2 deletions(-) --- a/drivers/misc/ntsync.c +++ b/drivers/misc/ntsync.c @@ -534,7 +534,7 @@ static int ntsync_mutex_kill(struct ntsy return ret; } -static int ntsync_event_set(struct ntsync_obj *event, void __user *argp) +static int ntsync_event_set(struct ntsync_obj *event, void __user *argp, bool pulse) { struct ntsync_device *dev = event->dev; __u32 prev_state; @@ -550,6 +550,8 @@ static int ntsync_event_set(struct ntsyn if (all) try_wake_all_obj(dev, event); try_wake_any_event(event); + if (pulse) + event->u.event.signaled = false; ntsync_unlock_obj(dev, event, all); @@ -605,9 +607,11 @@ static long ntsync_obj_ioctl(struct file case NTSYNC_IOC_MUTEX_KILL: return ntsync_mutex_kill(obj, argp); case NTSYNC_IOC_EVENT_SET: - return ntsync_event_set(obj, argp); + return ntsync_event_set(obj, argp, false); case NTSYNC_IOC_EVENT_RESET: return ntsync_event_reset(obj, argp); + case NTSYNC_IOC_EVENT_PULSE: + return ntsync_event_set(obj, argp, true); default: return -ENOIOCTLCMD; } --- a/include/uapi/linux/ntsync.h +++ b/include/uapi/linux/ntsync.h @@ -53,5 +53,6 @@ struct ntsync_wait_args { #define NTSYNC_IOC_MUTEX_KILL _IOW ('N', 0x86, __u32) #define NTSYNC_IOC_EVENT_SET _IOR ('N', 0x88, __u32) #define NTSYNC_IOC_EVENT_RESET _IOR ('N', 0x89, __u32) +#define NTSYNC_IOC_EVENT_PULSE _IOR ('N', 0x8a, __u32) #endif