[PATCH 6/7] [RFC] [media]: v4l2: introduce v4l2_timeval

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The v4l2 API uses a 'struct timeval' to communicate time stamps to user
space. This is broken on 32-bit architectures as soon as we have a C library
that defines time_t as 64 bit, which then changes the structure layout of
struct v4l2_buffer.

Fortunately, almost all v4l2 drivers use monotonic timestamps and call
v4l2_get_timestamp(), which means they don't also have a y2038 problem.
This means we can keep using the existing binary layout of the structure
and do not need to worry about defining a new kernel interface for
userland with 64-bit time_t.

A possible downside of this approach is that it breaks any user space
that tries to assign the timeval structure returned from the kernel
to another timeval, or to pass a pointer to it into a function that
expects a timeval. Those will cause a build-time warning or error
that can be fixed up in a backwards compatible way.

The alternative to this patch is to leave the structure using
'struct timeval', but then we have to rework the kernel to let
it handle both 32-bit and 64-bit time_t for 32-bit user space
processes.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
 drivers/media/pci/bt8xx/bttv-driver.c      |  2 +-
 drivers/media/pci/meye/meye.h              |  2 +-
 drivers/media/pci/zoran/zoran.h            |  2 +-
 drivers/media/platform/coda/coda.h         |  2 +-
 drivers/media/platform/omap/omap_vout.c    |  4 ++--
 drivers/media/platform/omap3isp/ispstat.h  |  2 +-
 drivers/media/platform/vim2m.c             |  2 +-
 drivers/media/platform/vivid/vivid-ctrls.c |  2 +-
 drivers/media/usb/cpia2/cpia2.h            |  2 +-
 drivers/media/usb/cpia2/cpia2_v4l.c        |  2 +-
 drivers/media/usb/gspca/gspca.c            |  2 +-
 drivers/media/usb/usbvision/usbvision.h    |  2 +-
 drivers/media/v4l2-core/v4l2-common.c      |  6 +++---
 include/media/v4l2-common.h                |  2 +-
 include/media/videobuf-core.h              |  2 +-
 include/trace/events/v4l2.h                | 12 ++++++++++--
 include/uapi/linux/omap3isp.h              |  2 +-
 include/uapi/linux/videodev2.h             |  8 +++++++-
 18 files changed, 36 insertions(+), 22 deletions(-)

diff --git a/drivers/media/pci/bt8xx/bttv-driver.c b/drivers/media/pci/bt8xx/bttv-driver.c
index 15a4ebc2844d..b0ed8d799c14 100644
--- a/drivers/media/pci/bt8xx/bttv-driver.c
+++ b/drivers/media/pci/bt8xx/bttv-driver.c
@@ -3585,7 +3585,7 @@ static void
 bttv_irq_wakeup_video(struct bttv *btv, struct bttv_buffer_set *wakeup,
 		      struct bttv_buffer_set *curr, unsigned int state)
 {
-	struct timeval ts;
+	struct v4l2_timeval ts;
 
 	v4l2_get_timestamp(&ts);
 
diff --git a/drivers/media/pci/meye/meye.h b/drivers/media/pci/meye/meye.h
index 751be5e533c7..a06aa5ba9abc 100644
--- a/drivers/media/pci/meye/meye.h
+++ b/drivers/media/pci/meye/meye.h
@@ -281,7 +281,7 @@
 struct meye_grab_buffer {
 	int state;			/* state of buffer */
 	unsigned long size;		/* size of jpg frame */
-	struct timeval timestamp;	/* timestamp */
+	struct v4l2_timeval timestamp;	/* timestamp */
 	unsigned long sequence;		/* sequence number */
 };
 
diff --git a/drivers/media/pci/zoran/zoran.h b/drivers/media/pci/zoran/zoran.h
index 4e7db8939c2b..9a9f782cede9 100644
--- a/drivers/media/pci/zoran/zoran.h
+++ b/drivers/media/pci/zoran/zoran.h
@@ -39,7 +39,7 @@ struct zoran_sync {
 	unsigned long frame;	/* number of buffer that has been free'd */
 	unsigned long length;	/* number of code bytes in buffer (capture only) */
 	unsigned long seq;	/* frame sequence number */
-	struct timeval timestamp;	/* timestamp */
+	struct v4l2_timeval timestamp;	/* timestamp */
 };
 
 
diff --git a/drivers/media/platform/coda/coda.h b/drivers/media/platform/coda/coda.h
index 59b2af9c7749..fa1e15a757cd 100644
--- a/drivers/media/platform/coda/coda.h
+++ b/drivers/media/platform/coda/coda.h
@@ -138,7 +138,7 @@ struct coda_buffer_meta {
 	struct list_head	list;
 	u32			sequence;
 	struct v4l2_timecode	timecode;
-	struct timeval		timestamp;
+	struct v4l2_timeval	timestamp;
 	u32			start;
 	u32			end;
 };
diff --git a/drivers/media/platform/omap/omap_vout.c b/drivers/media/platform/omap/omap_vout.c
index 70c28d19ea04..974a238a86fe 100644
--- a/drivers/media/platform/omap/omap_vout.c
+++ b/drivers/media/platform/omap/omap_vout.c
@@ -513,7 +513,7 @@ static int omapvid_apply_changes(struct omap_vout_device *vout)
 }
 
 static int omapvid_handle_interlace_display(struct omap_vout_device *vout,
-		unsigned int irqstatus, struct timeval timevalue)
+		unsigned int irqstatus, struct v4l2_timeval timevalue)
 {
 	u32 fid;
 
@@ -557,7 +557,7 @@ static void omap_vout_isr(void *arg, unsigned int irqstatus)
 	int ret, fid, mgr_id;
 	u32 addr, irq;
 	struct omap_overlay *ovl;
-	struct timeval timevalue;
+	struct v4l2_timeval timevalue;
 	struct omapvideo_info *ovid;
 	struct omap_dss_device *cur_display;
 	struct omap_vout_device *vout = (struct omap_vout_device *)arg;
diff --git a/drivers/media/platform/omap3isp/ispstat.h b/drivers/media/platform/omap3isp/ispstat.h
index 6d9b0244f320..7b4f136567a3 100644
--- a/drivers/media/platform/omap3isp/ispstat.h
+++ b/drivers/media/platform/omap3isp/ispstat.h
@@ -39,7 +39,7 @@ struct ispstat_buffer {
 	struct sg_table sgt;
 	void *virt_addr;
 	dma_addr_t dma_addr;
-	struct timeval ts;
+	struct v4l2_timeval ts;
 	u32 buf_size;
 	u32 frame_number;
 	u16 config_counter;
diff --git a/drivers/media/platform/vim2m.c b/drivers/media/platform/vim2m.c
index 295fde5fdb75..df5daac6d099 100644
--- a/drivers/media/platform/vim2m.c
+++ b/drivers/media/platform/vim2m.c
@@ -235,7 +235,7 @@ static int device_process(struct vim2m_ctx *ctx,
 	in_vb->v4l2_buf.sequence = q_data->sequence++;
 	memcpy(&out_vb->v4l2_buf.timestamp,
 			&in_vb->v4l2_buf.timestamp,
-			sizeof(struct timeval));
+			sizeof(struct v4l2_timeval));
 	if (in_vb->v4l2_buf.flags & V4L2_BUF_FLAG_TIMECODE)
 		memcpy(&out_vb->v4l2_buf.timecode, &in_vb->v4l2_buf.timecode,
 			sizeof(struct v4l2_timecode));
diff --git a/drivers/media/platform/vivid/vivid-ctrls.c b/drivers/media/platform/vivid/vivid-ctrls.c
index 339c8b7e53c8..065f3d6c2409 100644
--- a/drivers/media/platform/vivid/vivid-ctrls.c
+++ b/drivers/media/platform/vivid/vivid-ctrls.c
@@ -935,7 +935,7 @@ static const struct v4l2_ctrl_config vivid_ctrl_has_scaler_out = {
 static int vivid_streaming_s_ctrl(struct v4l2_ctrl *ctrl)
 {
 	struct vivid_dev *dev = container_of(ctrl->handler, struct vivid_dev, ctrl_hdl_streaming);
-	struct timeval tv;
+	struct v4l2_timeval tv;
 
 	switch (ctrl->id) {
 	case VIVID_CID_DQBUF_ERROR:
diff --git a/drivers/media/usb/cpia2/cpia2.h b/drivers/media/usb/cpia2/cpia2.h
index cdef677d57ec..3e7c523784e7 100644
--- a/drivers/media/usb/cpia2/cpia2.h
+++ b/drivers/media/usb/cpia2/cpia2.h
@@ -354,7 +354,7 @@ struct cpia2_sbuf {
 };
 
 struct framebuf {
-	struct timeval timestamp;
+	struct v4l2_timeval timestamp;
 	unsigned long seq;
 	int num;
 	int length;
diff --git a/drivers/media/usb/cpia2/cpia2_v4l.c b/drivers/media/usb/cpia2/cpia2_v4l.c
index 9caea8344547..ce50d7ef4da7 100644
--- a/drivers/media/usb/cpia2/cpia2_v4l.c
+++ b/drivers/media/usb/cpia2/cpia2_v4l.c
@@ -892,7 +892,7 @@ static int find_earliest_filled_buffer(struct camera_data *cam)
 				found = i;
 			} else {
 				/* find which buffer is earlier */
-				struct timeval *tv1, *tv2;
+				struct v4l2_timeval *tv1, *tv2;
 				tv1 = &cam->buffers[i].timestamp;
 				tv2 = &cam->buffers[found].timestamp;
 				if(tv1->tv_sec < tv2->tv_sec ||
diff --git a/drivers/media/usb/gspca/gspca.c b/drivers/media/usb/gspca/gspca.c
index af5cd8213e8b..c977937da9c4 100644
--- a/drivers/media/usb/gspca/gspca.c
+++ b/drivers/media/usb/gspca/gspca.c
@@ -1898,7 +1898,7 @@ static ssize_t dev_read(struct file *file, char __user *data,
 	struct gspca_dev *gspca_dev = video_drvdata(file);
 	struct gspca_frame *frame;
 	struct v4l2_buffer v4l2_buf;
-	struct timeval timestamp;
+	struct v4l2_timeval timestamp;
 	int n, ret, ret2;
 
 	PDEBUG(D_FRAM, "read (%zd)", count);
diff --git a/drivers/media/usb/usbvision/usbvision.h b/drivers/media/usb/usbvision/usbvision.h
index 4f2e4fde38f2..512de31613df 100644
--- a/drivers/media/usb/usbvision/usbvision.h
+++ b/drivers/media/usb/usbvision/usbvision.h
@@ -320,7 +320,7 @@ struct usbvision_frame {
 	long bytes_read;				/* amount of scanlength that has been read from data */
 	struct usbvision_v4l2_format_st v4l2_format;	/* format the user needs*/
 	int v4l2_linesize;				/* bytes for one videoline*/
-	struct timeval timestamp;
+	struct v4l2_timeval timestamp;
 	int sequence;					/* How many video frames we send to user */
 };
 
diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
index 5b808500e7e7..589fab615f21 100644
--- a/drivers/media/v4l2-core/v4l2-common.c
+++ b/drivers/media/v4l2-core/v4l2-common.c
@@ -396,11 +396,11 @@ const struct v4l2_frmsize_discrete *v4l2_find_nearest_format(
 }
 EXPORT_SYMBOL_GPL(v4l2_find_nearest_format);
 
-void v4l2_get_timestamp(struct timeval *tv)
+void v4l2_get_timestamp(struct v4l2_timeval *tv)
 {
-	struct timespec ts;
+	struct timespec64 ts;
 
-	ktime_get_ts(&ts);
+	ktime_get_ts64(&ts);
 	tv->tv_sec = ts.tv_sec;
 	tv->tv_usec = ts.tv_nsec / NSEC_PER_USEC;
 }
diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
index 1cc0c5ba16b3..6e77d889c3f8 100644
--- a/include/media/v4l2-common.h
+++ b/include/media/v4l2-common.h
@@ -187,6 +187,6 @@ const struct v4l2_frmsize_discrete *v4l2_find_nearest_format(
 		const struct v4l2_discrete_probe *probe,
 		s32 width, s32 height);
 
-void v4l2_get_timestamp(struct timeval *tv);
+void v4l2_get_timestamp(struct v4l2_timeval *tv);
 
 #endif /* V4L2_COMMON_H_ */
diff --git a/include/media/videobuf-core.h b/include/media/videobuf-core.h
index d760aa73ebbb..6381338a9588 100644
--- a/include/media/videobuf-core.h
+++ b/include/media/videobuf-core.h
@@ -80,7 +80,7 @@ struct videobuf_buffer {
 	struct list_head        queue;
 	wait_queue_head_t       done;
 	unsigned int            field_count;
-	struct timeval          ts;
+	struct v4l2_timeval     ts;
 
 	/* Memory type */
 	enum v4l2_memory        memory;
diff --git a/include/trace/events/v4l2.h b/include/trace/events/v4l2.h
index dbf017bfddd9..a88be48dc473 100644
--- a/include/trace/events/v4l2.h
+++ b/include/trace/events/v4l2.h
@@ -6,6 +6,14 @@
 
 #include <linux/tracepoint.h>
 
+#ifndef v4l2_timeval_to_ns
+#define v4l2_timeval_to_ns v4l2_timeval_to_ns
+static inline u64 v4l2_timeval_to_ns(struct v4l2_timeval *tv)
+{
+	return (u64)tv->tv_sec * NSEC_PER_SEC + tv->tv_usec * NSEC_PER_USEC;
+}
+#endif
+
 /* Enums require being exported to userspace, for user tool parsing */
 #undef EM
 #undef EMe
@@ -126,7 +134,7 @@ DECLARE_EVENT_CLASS(v4l2_event_class,
 		__entry->bytesused = buf->bytesused;
 		__entry->flags = buf->flags;
 		__entry->field = buf->field;
-		__entry->timestamp = timeval_to_ns(&buf->timestamp);
+		__entry->timestamp = v4l2_timeval_to_ns(&buf->timestamp);
 		__entry->timecode_type = buf->timecode.type;
 		__entry->timecode_flags = buf->timecode.flags;
 		__entry->timecode_frames = buf->timecode.frames;
@@ -211,7 +219,7 @@ DECLARE_EVENT_CLASS(vb2_event_class,
 		__entry->bytesused = vb->v4l2_planes[0].bytesused;
 		__entry->flags = vb->v4l2_buf.flags;
 		__entry->field = vb->v4l2_buf.field;
-		__entry->timestamp = timeval_to_ns(&vb->v4l2_buf.timestamp);
+		__entry->timestamp = v4l2_timeval_to_ns(&vb->v4l2_buf.timestamp);
 		__entry->timecode_type = vb->v4l2_buf.timecode.type;
 		__entry->timecode_flags = vb->v4l2_buf.timecode.flags;
 		__entry->timecode_frames = vb->v4l2_buf.timecode.frames;
diff --git a/include/uapi/linux/omap3isp.h b/include/uapi/linux/omap3isp.h
index c090cf9249bb..2d1a085d9c9b 100644
--- a/include/uapi/linux/omap3isp.h
+++ b/include/uapi/linux/omap3isp.h
@@ -164,7 +164,7 @@ struct omap3isp_h3a_aewb_config {
  * @config_counter: Number of the configuration associated with the data.
  */
 struct omap3isp_stat_data {
-	struct timeval ts;
+	struct v4l2_timeval ts;
 	void __user *buf;
 	__u32 buf_size;
 	__u16 frame_number;
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 3228fbebcd63..b02cf054fbb8 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -803,6 +803,12 @@ struct v4l2_plane {
 	__u32			reserved[11];
 };
 
+/* used for monotonic times, therefore y2038 safe */
+struct v4l2_timeval {
+	long tv_sec;
+	long tv_usec;
+};
+
 /**
  * struct v4l2_buffer - video buffer info
  * @index:	id number of the buffer
@@ -839,7 +845,7 @@ struct v4l2_buffer {
 	__u32			bytesused;
 	__u32			flags;
 	__u32			field;
-	struct timeval		timestamp;
+	struct v4l2_timeval	timestamp;
 	struct v4l2_timecode	timecode;
 	__u32			sequence;
 
-- 
2.1.0.rc2

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