PTP: introduce new versions of IOCTLs

The current version of the IOCTL have a small problem which prevents us
from extending the API by making use of reserved fields. In these new
IOCTLs, we are now making sure that flags and rsv fields are zero which
will allow us to extend the API in the future.
Reviewed-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/ptp/ptp_chardev.c

@@ -126,7 +126,9 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 	switch (cmd) {
 
 	case PTP_CLOCK_GETCAPS:
+	case PTP_CLOCK_GETCAPS2:
 		memset(&caps, 0, sizeof(caps));
+
 		caps.max_adj = ptp->info->max_adj;
 		caps.n_alarm = ptp->info->n_alarm;
 		caps.n_ext_ts = ptp->info->n_ext_ts;
@@ -139,11 +141,24 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		break;
 
 	case PTP_EXTTS_REQUEST:
+	case PTP_EXTTS_REQUEST2:
+		memset(&req, 0, sizeof(req));
+
 		if (copy_from_user(&req.extts, (void __user *)arg,
 				   sizeof(req.extts))) {
 			err = -EFAULT;
 			break;
 		}
+		if (((req.extts.flags & ~PTP_EXTTS_VALID_FLAGS) ||
+			req.extts.rsv[0] || req.extts.rsv[1]) &&
+			cmd == PTP_EXTTS_REQUEST2) {
+			err = -EINVAL;
+			break;
+		} else if (cmd == PTP_EXTTS_REQUEST) {
+			req.extts.flags &= ~PTP_EXTTS_VALID_FLAGS;
+			req.extts.rsv[0] = 0;
+			req.extts.rsv[1] = 0;
+		}
 		if (req.extts.index >= ops->n_ext_ts) {
 			err = -EINVAL;
 			break;
@@ -154,11 +169,27 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		break;
 
 	case PTP_PEROUT_REQUEST:
+	case PTP_PEROUT_REQUEST2:
+		memset(&req, 0, sizeof(req));
+
 		if (copy_from_user(&req.perout, (void __user *)arg,
 				   sizeof(req.perout))) {
 			err = -EFAULT;
 			break;
 		}
+		if (((req.perout.flags & ~PTP_PEROUT_VALID_FLAGS) ||
+			req.perout.rsv[0] || req.perout.rsv[1] ||
+			req.perout.rsv[2] || req.perout.rsv[3]) &&
+			cmd == PTP_PEROUT_REQUEST2) {
+			err = -EINVAL;
+			break;
+		} else if (cmd == PTP_PEROUT_REQUEST) {
+			req.perout.flags &= ~PTP_PEROUT_VALID_FLAGS;
+			req.perout.rsv[0] = 0;
+			req.perout.rsv[1] = 0;
+			req.perout.rsv[2] = 0;
+			req.perout.rsv[3] = 0;
+		}
 		if (req.perout.index >= ops->n_per_out) {
 			err = -EINVAL;
 			break;
@@ -169,6 +200,9 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		break;
 
 	case PTP_ENABLE_PPS:
+	case PTP_ENABLE_PPS2:
+		memset(&req, 0, sizeof(req));
+
 		if (!capable(CAP_SYS_TIME))
 			return -EPERM;
 		req.type = PTP_CLK_REQ_PPS;
@@ -177,6 +211,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		break;
 
 	case PTP_SYS_OFFSET_PRECISE:
+	case PTP_SYS_OFFSET_PRECISE2:
 		if (!ptp->info->getcrosststamp) {
 			err = -EOPNOTSUPP;
 			break;
@@ -201,6 +236,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		break;
 
 	case PTP_SYS_OFFSET_EXTENDED:
+	case PTP_SYS_OFFSET_EXTENDED2:
 		if (!ptp->info->gettimex64) {
 			err = -EOPNOTSUPP;
 			break;
@@ -232,6 +268,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		break;
 
 	case PTP_SYS_OFFSET:
+	case PTP_SYS_OFFSET2:
 		sysoff = memdup_user((void __user *)arg, sizeof(*sysoff));
 		if (IS_ERR(sysoff)) {
 			err = PTR_ERR(sysoff);
@@ -266,10 +303,23 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		break;
 
 	case PTP_PIN_GETFUNC:
+	case PTP_PIN_GETFUNC2:
 		if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
 			err = -EFAULT;
 			break;
 		}
+		if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
+				|| pd.rsv[3] || pd.rsv[4])
+			&& cmd == PTP_PIN_GETFUNC2) {
+			err = -EINVAL;
+			break;
+		} else if (cmd == PTP_PIN_GETFUNC) {
+			pd.rsv[0] = 0;
+			pd.rsv[1] = 0;
+			pd.rsv[2] = 0;
+			pd.rsv[3] = 0;
+			pd.rsv[4] = 0;
+		}
 		pin_index = pd.index;
 		if (pin_index >= ops->n_pins) {
 			err = -EINVAL;
@@ -285,10 +335,23 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		break;
 
 	case PTP_PIN_SETFUNC:
+	case PTP_PIN_SETFUNC2:
 		if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
 			err = -EFAULT;
 			break;
 		}
+		if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
+				|| pd.rsv[3] || pd.rsv[4])
+			&& cmd == PTP_PIN_SETFUNC2) {
+			err = -EINVAL;
+			break;
+		} else if (cmd == PTP_PIN_SETFUNC) {
+			pd.rsv[0] = 0;
+			pd.rsv[1] = 0;
+			pd.rsv[2] = 0;
+			pd.rsv[3] = 0;
+			pd.rsv[4] = 0;
+		}
 		pin_index = pd.index;
 		if (pin_index >= ops->n_pins) {
 			err = -EINVAL;

include/uapi/linux/ptp_clock.h

@@ -25,10 +25,20 @@
 #include <linux/ioctl.h>
 #include <linux/types.h>
 
-/* PTP_xxx bits, for the flags field within the request structures. */
+/*
+ * Bits of the ptp_extts_request.flags field:
+ */
 #define PTP_ENABLE_FEATURE (1<<0)
 #define PTP_RISING_EDGE    (1<<1)
 #define PTP_FALLING_EDGE   (1<<2)
+#define PTP_EXTTS_VALID_FLAGS	(PTP_ENABLE_FEATURE |	\
+				 PTP_RISING_EDGE |	\
+				 PTP_FALLING_EDGE)
+
+/*
+ * Bits of the ptp_perout_request.flags field:
+ */
+#define PTP_PEROUT_VALID_FLAGS (0)
 
 /*
  * struct ptp_clock_time - represents a time value
@@ -149,6 +159,18 @@ struct ptp_pin_desc {
 #define PTP_SYS_OFFSET_EXTENDED \
 	_IOWR(PTP_CLK_MAGIC, 9, struct ptp_sys_offset_extended)
 
+#define PTP_CLOCK_GETCAPS2  _IOR(PTP_CLK_MAGIC, 10, struct ptp_clock_caps)
+#define PTP_EXTTS_REQUEST2  _IOW(PTP_CLK_MAGIC, 11, struct ptp_extts_request)
+#define PTP_PEROUT_REQUEST2 _IOW(PTP_CLK_MAGIC, 12, struct ptp_perout_request)
+#define PTP_ENABLE_PPS2     _IOW(PTP_CLK_MAGIC, 13, int)
+#define PTP_SYS_OFFSET2     _IOW(PTP_CLK_MAGIC, 14, struct ptp_sys_offset)
+#define PTP_PIN_GETFUNC2    _IOWR(PTP_CLK_MAGIC, 15, struct ptp_pin_desc)
+#define PTP_PIN_SETFUNC2    _IOW(PTP_CLK_MAGIC, 16, struct ptp_pin_desc)
+#define PTP_SYS_OFFSET_PRECISE2 \
+	_IOWR(PTP_CLK_MAGIC, 17, struct ptp_sys_offset_precise)
+#define PTP_SYS_OFFSET_EXTENDED2 \
+	_IOWR(PTP_CLK_MAGIC, 18, struct ptp_sys_offset_extended)
+
 struct ptp_extts_event {
 	struct ptp_clock_time t; /* Time event occured. */
 	unsigned int index;      /* Which channel produced the event. */