sk: change sk_interface_phc to sk_get_ts_info

this patch changes sk_interface_phc to sk_get_ts_info, by allowing the function
to store all the data returned by Ethtool's get_ts_info IOCTL in a struct. A new
struct "sk_ts_info" contains the same data as well as a field for specifying the
structure as valid (in order to support old kernels without the IOCTL). The
valid field should be set only when the IOCTL successfully populates the fields.

A follow-on patch will add new functionality possible because of these
changes. This patch only updates the programs which use the call to perform the
minimum they already do, using the new interface.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>

config.c

@@ -464,6 +464,8 @@ int config_create_interface(char *name, struct config *cfg)
 	iface->transport = cfg->transport;
 	memcpy(&iface->pod, &cfg->pod, sizeof(cfg->pod));
 
+	sk_get_ts_info(name, &iface->ts_info);
+
 	cfg->nports++;
 
 	return i;

config.h

@@ -24,6 +24,7 @@
 #include "dm.h"
 #include "transport.h"
 #include "servo.h"
+#include "sk.h"
 
 #define MAX_PORTS 8
 #define MAX_IFNAME_SIZE 16
@@ -34,6 +35,7 @@ struct interface {
 	enum delay_mechanism dm;
 	enum transport_type transport;
 	struct port_defaults pod;
+	struct sk_ts_info ts_info;
 };
 
 #define CFG_IGNORE_DM           (1 << 0)

phc2sys.c

@@ -298,13 +298,13 @@ int main(int argc, char *argv[])
 	}
 
 	if (src == CLOCK_INVALID && ethdev) {
-		int phc_index = -1;
+		struct sk_ts_info ts_info;
 		char phc_device[16];
-		if (sk_interface_phc(ethdev, &phc_index) || phc_index < 0) {
+		if (sk_get_ts_info(ethdev, &ts_info) || !ts_info.valid) {
 			fprintf(stderr, "can't autodiscover PHC device\n");
 			return -1;
 		}
-		sprintf(phc_device, "/dev/ptp%d", phc_index);
+		sprintf(phc_device, "/dev/ptp%d", ts_info.phc_index);
 		src = clock_open(phc_device);
 	}
 	if (!(device || src != CLOCK_INVALID) || dst == CLOCK_INVALID) {

port.c

@@ -1663,7 +1663,6 @@ struct port *port_open(int phc_index,
 		       struct clock *clock)
 {
 	struct port *p = malloc(sizeof(*p));
-	int checked_phc_index = -1;
 
 	if (!p)
 		return NULL;
@@ -1672,12 +1671,12 @@ struct port *port_open(int phc_index,
 
 	if (interface->transport == TRANS_UDS)
 		; /* UDS cannot have a PHC. */
-	else if (sk_interface_phc(interface->name, &checked_phc_index))
+	else if (!interface->ts_info.valid)
 		pr_warning("port %d: get_ts_info not supported", number);
-	else if (phc_index >= 0 && phc_index != checked_phc_index) {
+	else if (phc_index >= 0 && phc_index != interface->ts_info.phc_index) {
 		pr_err("port %d: PHC device mismatch", number);
 		pr_err("port %d: /dev/ptp%d requested, but /dev/ptp%d attached",
-		       number, phc_index, checked_phc_index);
+		       number, phc_index, interface->ts_info.phc_index);
 		free(p);
 		return NULL;
 	}

ptp4l.c

@@ -263,9 +263,12 @@ int main(int argc, char *argv[])
 			fprintf(stderr, "bad ptp device string\n");
 			return -1;
 		}
-	} else if (sk_interface_phc(iface[0].name, &phc_index)) {
-		fprintf(stderr, "get_ts_info not supported\n"
-				"please specify ptp device\n");
+	} else if (iface[0].ts_info.valid) {
+		phc_index = iface[0].ts_info.phc_index;
+	} else {
+		fprintf(stderr, "ptp device not specified and\n"
+			        "automatic determination is not\n"
+			        "supported. please specify ptp device\n");
 		return -1;
 	}
 

sk.c

@@ -88,7 +88,7 @@ int sk_interface_index(int fd, char *name)
 	return ifreq.ifr_ifindex;
 }
 
-int sk_interface_phc(char *name, int *index)
+int sk_get_ts_info(char *name, struct sk_ts_info *sk_info)
 {
 #ifdef ETHTOOL_GET_TS_INFO
 	struct ethtool_ts_info info;
@@ -98,29 +98,38 @@ int sk_interface_phc(char *name, int *index)
 	memset(&ifr, 0, sizeof(ifr));
 	memset(&info, 0, sizeof(info));
 	info.cmd = ETHTOOL_GET_TS_INFO;
-	strcpy(ifr.ifr_name, name);
+	strncpy(ifr.ifr_name, name, IFNAMSIZ - 1);
 	ifr.ifr_data = (char *) &info;
 	fd = socket(AF_INET, SOCK_DGRAM, 0);
 
 	if (fd < 0) {
 		pr_err("socket failed: %m");
-		return -1;
+		goto failed;
 	}
 
 	err = ioctl(fd, SIOCETHTOOL, &ifr);
 	if (err < 0) {
 		pr_err("ioctl SIOCETHTOOL failed: %m");
 		close(fd);
-		return -1;
+		goto failed;
 	}
 
 	close(fd);
-	*index = info.phc_index;
 
-	return info.phc_index < 0 ? -1 : 0;
-#else
-	return -1;
+	/* copy the necessary data to sk_info */
+	memset(sk_info, 0, sizeof(struct sk_ts_info));
+	sk_info->valid = 1;
+	sk_info->phc_index = info.phc_index;
+	sk_info->so_timestamping = info.so_timestamping;
+	sk_info->tx_types = info.tx_types;
+	sk_info->rx_filters = info.rx_filters;
+
+	return 0;
 #endif
+failed:
+	/* clear data and ensure it is not marked valid */
+	memset(sk_info, 0, sizeof(struct sk_ts_info));
+	return -1;
 }
 
 int sk_interface_macaddr(char *name, unsigned char *mac, int len)

sk.h

@@ -22,6 +22,19 @@
 
 #include "transport.h"
 
+/**
+ * struct sk_ts_info - supported timestamping information
+ * @valid: set to non-zero when the info struct contains valid data
+ * @info: structure containing the values returned by GET_TS_INFO
+ */
+struct sk_ts_info {
+	int valid;
+	int phc_index;
+	unsigned int so_timestamping;
+	unsigned int tx_types;
+	unsigned int rx_filters;
+};
+
 /**
  * Obtain the numerical index from a network interface by name.
  * @param fd      An open socket.
@@ -31,12 +44,12 @@
 int sk_interface_index(int fd, char *device);
 
 /**
- * Obtain the PHC device index of a network interface.
+ * Obtain supported timestamping information
  * @param name	    The name of the interface
- * @return index    The non-negative phc index associated with this iface.
- *                  On error a negative integer is returned.
+ * @param info      Struct containing obtained timestamping information.
+ * @return          zero on success, negative on failure.
  */
-int sk_interface_phc(char *name, int *index);
+int sk_get_ts_info(char *name, struct sk_ts_info *sk_info);
 
 /**
  * Obtain the MAC address of a network interface.