[tip:timers/core] kthread: Convert callback to use from_timer()

[tip-bot for Kees Cook]

Commit-ID:  fe5c3b69b540e3387223a696f327c1bb8880d1ac
Gitweb:     https://git.kernel.org/tip/fe5c3b69b540e3387223a696f327c1bb8880d1ac
Author:     Kees Cook <keescook@xxxxxxxxxxxx>
AuthorDate: Wed, 4 Oct 2017 16:27:06 -0700
Committer:  Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Thu, 5 Oct 2017 15:01:22 +0200

kthread: Convert callback to use from_timer()

In preparation for unconditionally passing the struct timer_list pointer
to all timer callbacks, switch kthread to use from_timer() and pass the
timer pointer explicitly.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: Len Brown <len.brown@xxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Lai Jiangshan <jiangshanlai@xxxxxxxxx>
Cc: Sebastian Reichel <sre@xxxxxxxxxx>
Cc: Kalle Valo <kvalo@xxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Pavel Machek <pavel@xxxxxx>
Cc: linux1394-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: Chris Metcalf <cmetcalf@xxxxxxxxxxxx>
Cc: linux-s390@xxxxxxxxxxxxxxx
Cc: linux-wireless@xxxxxxxxxxxxxxx
Cc: "James E.J. Bottomley" <jejb@xxxxxxxxxxxxxxxxxx>
Cc: Wim Van Sebroeck <wim@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Ursula Braun <ubraun@xxxxxxxxxxxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Cc: Harish Patil <harish.patil@xxxxxxxxxx>
Cc: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Cc: Manish Chopra <manish.chopra@xxxxxxxxxx>
Cc: Petr Mladek <pmladek@xxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: linux-pm@xxxxxxxxxxxxxxx
Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Cc: Julian Wiedmann <jwi@xxxxxxxxxxxxxxxxxx>
Cc: John Stultz <john.stultz@xxxxxxxxxx>
Cc: Mark Gross <mark.gross@xxxxxxxxx>
Cc: linux-watchdog@xxxxxxxxxxxxxxx
Cc: linux-scsi@xxxxxxxxxxxxxxx
Cc: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Stefan Richter <stefanr@xxxxxxxxxxxxxxxxx>
Cc: Michael Reed <mdr@xxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx>
Link: https://lkml.kernel.org/r/1507159627-127660-13-git-send-email-keescook@xxxxxxxxxxxx

---
 include/linux/kthread.h | 10 +++++-----
 kernel/kthread.c        | 10 ++++------
 2 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/include/linux/kthread.h b/include/linux/kthread.h
index 0d622b3..35cbe3b 100644
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h
@@ -75,7 +75,7 @@ extern int tsk_fork_get_node(struct task_struct *tsk);
  */
 struct kthread_work;
 typedef void (*kthread_work_func_t)(struct kthread_work *work);
-void kthread_delayed_work_timer_fn(unsigned long __data);
+void kthread_delayed_work_timer_fn(struct timer_list *t);
 
 enum {
 	KTW_FREEZABLE		= 1 << 0,	/* freeze during suspend */
@@ -116,8 +116,8 @@ struct kthread_delayed_work {
 
 #define KTHREAD_DELAYED_WORK_INIT(dwork, fn) {				\
 	.work = KTHREAD_WORK_INIT((dwork).work, (fn)),			\
-	.timer = __TIMER_INITIALIZER(kthread_delayed_work_timer_fn,	\
-				     (unsigned long)&(dwork),		\
+	.timer = __TIMER_INITIALIZER((TIMER_FUNC_TYPE)kthread_delayed_work_timer_fn,\
+				     (TIMER_DATA_TYPE)&(dwork.timer),	\
 				     TIMER_IRQSAFE),			\
 	}
 
@@ -164,8 +164,8 @@ extern void __kthread_init_worker(struct kthread_worker *worker,
 	do {								\
 		kthread_init_work(&(dwork)->work, (fn));		\
 		__setup_timer(&(dwork)->timer,				\
-			      kthread_delayed_work_timer_fn,		\
-			      (unsigned long)(dwork),			\
+			      (TIMER_FUNC_TYPE)kthread_delayed_work_timer_fn,\
+			      (TIMER_DATA_TYPE)&(dwork)->timer,		\
 			      TIMER_IRQSAFE);				\
 	} while (0)
 
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 1c19edf..ba3992c 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -798,15 +798,14 @@ EXPORT_SYMBOL_GPL(kthread_queue_work);
 /**
  * kthread_delayed_work_timer_fn - callback that queues the associated kthread
  *	delayed work when the timer expires.
- * @__data: pointer to the data associated with the timer
+ * @t: pointer to the expired timer
  *
  * The format of the function is defined by struct timer_list.
  * It should have been called from irqsafe timer with irq already off.
  */
-void kthread_delayed_work_timer_fn(unsigned long __data)
+void kthread_delayed_work_timer_fn(struct timer_list *t)
 {
-	struct kthread_delayed_work *dwork =
-		(struct kthread_delayed_work *)__data;
+	struct kthread_delayed_work *dwork = from_timer(dwork, t, timer);
 	struct kthread_work *work = &dwork->work;
 	struct kthread_worker *worker = work->worker;
 
@@ -837,8 +836,7 @@ void __kthread_queue_delayed_work(struct kthread_worker *worker,
 	struct timer_list *timer = &dwork->timer;
 	struct kthread_work *work = &dwork->work;
 
-	WARN_ON_ONCE(timer->function != kthread_delayed_work_timer_fn ||
-		     timer->data != (unsigned long)dwork);
+	WARN_ON_ONCE(timer->function != (TIMER_FUNC_TYPE)kthread_delayed_work_timer_fn);
 
 	/*
 	 * If @delay is 0, queue @dwork->work immediately.  This is for