[PATCH] media: pvrusb2: Convert timers to use timer_setup()

From: Kees Cook
Date: Tue Oct 24 2017 - 11:23:42 EST


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

Cc: Mike Isely <isely@xxxxxxxxx>
Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Cc: linux-media@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
drivers/media/usb/pvrusb2/pvrusb2-hdw.c | 64 ++++++++++++++++++---------------
1 file changed, 36 insertions(+), 28 deletions(-)

diff --git a/drivers/media/usb/pvrusb2/pvrusb2-hdw.c b/drivers/media/usb/pvrusb2/pvrusb2-hdw.c
index ad5b25b89699..8289ee482f49 100644
--- a/drivers/media/usb/pvrusb2/pvrusb2-hdw.c
+++ b/drivers/media/usb/pvrusb2/pvrusb2-hdw.c
@@ -330,10 +330,10 @@ static void pvr2_hdw_state_log_state(struct pvr2_hdw *);
static int pvr2_hdw_cmd_usbstream(struct pvr2_hdw *hdw,int runFl);
static int pvr2_hdw_commit_setup(struct pvr2_hdw *hdw);
static int pvr2_hdw_get_eeprom_addr(struct pvr2_hdw *hdw);
-static void pvr2_hdw_quiescent_timeout(unsigned long);
-static void pvr2_hdw_decoder_stabilization_timeout(unsigned long);
-static void pvr2_hdw_encoder_wait_timeout(unsigned long);
-static void pvr2_hdw_encoder_run_timeout(unsigned long);
+static void pvr2_hdw_quiescent_timeout(struct timer_list *);
+static void pvr2_hdw_decoder_stabilization_timeout(struct timer_list *);
+static void pvr2_hdw_encoder_wait_timeout(struct timer_list *);
+static void pvr2_hdw_encoder_run_timeout(struct timer_list *);
static int pvr2_issue_simple_cmd(struct pvr2_hdw *,u32);
static int pvr2_send_request_ex(struct pvr2_hdw *hdw,
unsigned int timeout,int probe_fl,
@@ -2373,18 +2373,15 @@ struct pvr2_hdw *pvr2_hdw_create(struct usb_interface *intf,
}
if (!hdw) goto fail;

- setup_timer(&hdw->quiescent_timer, pvr2_hdw_quiescent_timeout,
- (unsigned long)hdw);
+ timer_setup(&hdw->quiescent_timer, pvr2_hdw_quiescent_timeout, 0);

- setup_timer(&hdw->decoder_stabilization_timer,
- pvr2_hdw_decoder_stabilization_timeout,
- (unsigned long)hdw);
+ timer_setup(&hdw->decoder_stabilization_timer,
+ pvr2_hdw_decoder_stabilization_timeout, 0);

- setup_timer(&hdw->encoder_wait_timer, pvr2_hdw_encoder_wait_timeout,
- (unsigned long)hdw);
+ timer_setup(&hdw->encoder_wait_timer, pvr2_hdw_encoder_wait_timeout,
+ 0);

- setup_timer(&hdw->encoder_run_timer, pvr2_hdw_encoder_run_timeout,
- (unsigned long)hdw);
+ timer_setup(&hdw->encoder_run_timer, pvr2_hdw_encoder_run_timeout, 0);

hdw->master_state = PVR2_STATE_DEAD;

@@ -3539,10 +3536,16 @@ static void pvr2_ctl_read_complete(struct urb *urb)
complete(&hdw->ctl_done);
}

+struct hdw_timer {
+ struct timer_list timer;
+ struct pvr2_hdw *hdw;
+};

-static void pvr2_ctl_timeout(unsigned long data)
+static void pvr2_ctl_timeout(struct timer_list *t)
{
- struct pvr2_hdw *hdw = (struct pvr2_hdw *)data;
+ struct hdw_timer *timer = from_timer(timer, t, timer);
+ struct pvr2_hdw *hdw = timer->hdw;
+
if (hdw->ctl_write_pend_flag || hdw->ctl_read_pend_flag) {
hdw->ctl_timeout_flag = !0;
if (hdw->ctl_write_pend_flag)
@@ -3564,7 +3567,10 @@ static int pvr2_send_request_ex(struct pvr2_hdw *hdw,
{
unsigned int idx;
int status = 0;
- struct timer_list timer;
+ struct hdw_timer timer = {
+ .hdw = hdw,
+ };
+
if (!hdw->ctl_lock_held) {
pvr2_trace(PVR2_TRACE_ERROR_LEGS,
"Attempted to execute control transfer without lock!!");
@@ -3621,8 +3627,8 @@ static int pvr2_send_request_ex(struct pvr2_hdw *hdw,
hdw->ctl_timeout_flag = 0;
hdw->ctl_write_pend_flag = 0;
hdw->ctl_read_pend_flag = 0;
- setup_timer(&timer, pvr2_ctl_timeout, (unsigned long)hdw);
- timer.expires = jiffies + timeout;
+ timer_setup_on_stack(&timer.timer, pvr2_ctl_timeout, 0);
+ timer.timer.expires = jiffies + timeout;

if (write_len && write_data) {
hdw->cmd_debug_state = 2;
@@ -3677,7 +3683,7 @@ status);
}

/* Start timer */
- add_timer(&timer);
+ add_timer(&timer.timer);

/* Now wait for all I/O to complete */
hdw->cmd_debug_state = 4;
@@ -3687,7 +3693,7 @@ status);
hdw->cmd_debug_state = 5;

/* Stop timer */
- del_timer_sync(&timer);
+ del_timer_sync(&timer.timer);

hdw->cmd_debug_state = 6;
status = 0;
@@ -3769,6 +3775,8 @@ status);
if ((status < 0) && (!probe_fl)) {
pvr2_hdw_render_useless(hdw);
}
+ destroy_timer_on_stack(&timer.timer);
+
return status;
}

@@ -4366,9 +4374,9 @@ static int state_eval_encoder_run(struct pvr2_hdw *hdw)


/* Timeout function for quiescent timer. */
-static void pvr2_hdw_quiescent_timeout(unsigned long data)
+static void pvr2_hdw_quiescent_timeout(struct timer_list *t)
{
- struct pvr2_hdw *hdw = (struct pvr2_hdw *)data;
+ struct pvr2_hdw *hdw = from_timer(hdw, t, quiescent_timer);
hdw->state_decoder_quiescent = !0;
trace_stbit("state_decoder_quiescent",hdw->state_decoder_quiescent);
hdw->state_stale = !0;
@@ -4377,9 +4385,9 @@ static void pvr2_hdw_quiescent_timeout(unsigned long data)


/* Timeout function for decoder stabilization timer. */
-static void pvr2_hdw_decoder_stabilization_timeout(unsigned long data)
+static void pvr2_hdw_decoder_stabilization_timeout(struct timer_list *t)
{
- struct pvr2_hdw *hdw = (struct pvr2_hdw *)data;
+ struct pvr2_hdw *hdw = from_timer(hdw, t, decoder_stabilization_timer);
hdw->state_decoder_ready = !0;
trace_stbit("state_decoder_ready", hdw->state_decoder_ready);
hdw->state_stale = !0;
@@ -4388,9 +4396,9 @@ static void pvr2_hdw_decoder_stabilization_timeout(unsigned long data)


/* Timeout function for encoder wait timer. */
-static void pvr2_hdw_encoder_wait_timeout(unsigned long data)
+static void pvr2_hdw_encoder_wait_timeout(struct timer_list *t)
{
- struct pvr2_hdw *hdw = (struct pvr2_hdw *)data;
+ struct pvr2_hdw *hdw = from_timer(hdw, t, encoder_wait_timer);
hdw->state_encoder_waitok = !0;
trace_stbit("state_encoder_waitok",hdw->state_encoder_waitok);
hdw->state_stale = !0;
@@ -4399,9 +4407,9 @@ static void pvr2_hdw_encoder_wait_timeout(unsigned long data)


/* Timeout function for encoder run timer. */
-static void pvr2_hdw_encoder_run_timeout(unsigned long data)
+static void pvr2_hdw_encoder_run_timeout(struct timer_list *t)
{
- struct pvr2_hdw *hdw = (struct pvr2_hdw *)data;
+ struct pvr2_hdw *hdw = from_timer(hdw, t, encoder_run_timer);
if (!hdw->state_encoder_runok) {
hdw->state_encoder_runok = !0;
trace_stbit("state_encoder_runok",hdw->state_encoder_runok);
--
2.7.4


--
Kees Cook
Pixel Security