qeth: bridgeport support - basic control

Introduce functions to assign roles and check state of bridgeport-capable
HiperSocket devices, and sysfs attributes providing access to these
functions from userspace. Introduce udev events emitted when the state
of a bridgeport device changes.
Signed-off-by: Eugene Crosser <eugene.crosser@ru.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Reviewed-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/s390/qeth.txt

+IBM s390 QDIO Ethernet Driver
+
+HiperSockets Bridge Port Support
+
+Uevents
+
+To generate the events the device must be assigned a role of either
+a primary or a secondary Bridge Port. For more information, see
+"z/VM Connectivity, SC24-6174".
+
+When run on HiperSockets Bridge Capable Port hardware, and the state
+of some configured Bridge Port device on the channel changes, a udev
+event with ACTION=CHANGE is emitted on behalf of the corresponding
+ccwgroup device. The event has the following attributes:
+
+BRIDGEPORT=statechange -  indicates that the Bridge Port device changed
+  its state.
+
+ROLE={primary|secondary|none} - the role assigned to the port.
+
+STATE={active|standby|inactive} - the newly assumed state of the port.

drivers/s390/net/Makefile

@@ -11,7 +11,7 @@ obj-$(CONFIG_LCS) += lcs.o
 obj-$(CONFIG_CLAW) += claw.o
 qeth-y += qeth_core_sys.o qeth_core_main.o qeth_core_mpc.o
 obj-$(CONFIG_QETH) += qeth.o
-qeth_l2-y += qeth_l2_main.o
+qeth_l2-y += qeth_l2_main.o qeth_l2_sys.o
 obj-$(CONFIG_QETH_L2) += qeth_l2.o
 qeth_l3-y += qeth_l3_main.o qeth_l3_sys.o
 obj-$(CONFIG_QETH_L3) += qeth_l3.o

drivers/s390/net/qeth_core.h

@@ -156,6 +156,24 @@ struct qeth_ipa_info {
 	__u32 enabled_funcs;
 };
 
+/* SETBRIDGEPORT stuff */
+enum qeth_sbp_roles {
+	QETH_SBP_ROLE_NONE	= 0,
+	QETH_SBP_ROLE_PRIMARY	= 1,
+	QETH_SBP_ROLE_SECONDARY	= 2,
+};
+
+enum qeth_sbp_states {
+	QETH_SBP_STATE_INACTIVE	= 0,
+	QETH_SBP_STATE_STANDBY	= 1,
+	QETH_SBP_STATE_ACTIVE	= 2,
+};
+
+struct qeth_sbp_info {
+	__u32 supported_funcs;
+	enum qeth_sbp_roles role;
+};
+
 static inline int qeth_is_ipa_supported(struct qeth_ipa_info *ipa,
 		enum qeth_ipa_funcs func)
 {
@@ -672,6 +690,7 @@ struct qeth_card_options {
 	struct qeth_ipa_info adp; /*Adapter parameters*/
 	struct qeth_routing_info route6;
 	struct qeth_ipa_info ipa6;
+	struct qeth_sbp_info sbp; /* SETBRIDGEPORT options */
 	int fake_broadcast;
 	int add_hhlen;
 	int layer2;
@@ -857,6 +876,7 @@ extern struct qeth_discipline qeth_l2_discipline;
 extern struct qeth_discipline qeth_l3_discipline;
 extern const struct attribute_group *qeth_generic_attr_groups[];
 extern const struct attribute_group *qeth_osn_attr_groups[];
+extern struct workqueue_struct *qeth_wq;
 
 const char *qeth_get_cardname_short(struct qeth_card *);
 int qeth_realloc_buffer_pool(struct qeth_card *, int);
@@ -925,6 +945,11 @@ int qeth_query_card_info(struct qeth_card *card,
 int qeth_send_control_data(struct qeth_card *, int, struct qeth_cmd_buffer *,
 	int (*reply_cb)(struct qeth_card *, struct qeth_reply*, unsigned long),
 	void *reply_param);
+void qeth_bridge_state_change(struct qeth_card *card, struct qeth_ipa_cmd *cmd);
+void qeth_bridgeport_query_support(struct qeth_card *card);
+int qeth_bridgeport_query_ports(struct qeth_card *card,
+	enum qeth_sbp_roles *role, enum qeth_sbp_states *state);
+int qeth_bridgeport_setrole(struct qeth_card *card, enum qeth_sbp_roles role);
 int qeth_get_priority_queue(struct qeth_card *, struct sk_buff *, int, int);
 int qeth_get_elements_no(struct qeth_card *, struct sk_buff *, int);
 int qeth_get_elements_for_frags(struct sk_buff *);

drivers/s390/net/qeth_core_main.c

@@ -68,7 +68,7 @@ static void qeth_clear_output_buffer(struct qeth_qdio_out_q *queue,
 		enum qeth_qdio_buffer_states newbufstate);
 static int qeth_init_qdio_out_buf(struct qeth_qdio_out_q *, int);
 
-static struct workqueue_struct *qeth_wq;
+struct workqueue_struct *qeth_wq;
 
 static void qeth_close_dev_handler(struct work_struct *work)
 {
@@ -615,6 +615,13 @@ static struct qeth_ipa_cmd *qeth_check_ipa_data(struct qeth_card *card,
 					card->info.hwtrap = 2;
 				qeth_schedule_recovery(card);
 				return NULL;
+			case IPA_CMD_SETBRIDGEPORT:
+				if (cmd->data.sbp.hdr.command_code ==
+					IPA_SBP_BRIDGE_PORT_STATE_CHANGE) {
+					qeth_bridge_state_change(card, cmd);
+					return NULL;
+				} else
+					return cmd;
 			case IPA_CMD_MODCCID:
 				return cmd;
 			case IPA_CMD_REGISTER_LOCAL_ADDR:
@@ -4956,12 +4963,17 @@ int qeth_core_hardsetup_card(struct qeth_card *card)
 
 	card->options.ipa4.supported_funcs = 0;
 	card->options.adp.supported_funcs = 0;
+	card->options.sbp.supported_funcs = 0;
 	card->info.diagass_support = 0;
 	qeth_query_ipassists(card, QETH_PROT_IPV4);
 	if (qeth_is_supported(card, IPA_SETADAPTERPARMS))
 		qeth_query_setadapterparms(card);
 	if (qeth_adp_supported(card, IPA_SETADP_SET_DIAG_ASSIST))
 		qeth_query_setdiagass(card);
+	qeth_bridgeport_query_support(card);
+	if (card->options.sbp.supported_funcs)
+		dev_info(&card->gdev->dev,
+		"The device represents a HiperSockets Bridge Capable Port\n");
 	return 0;
 out:
 	dev_warn(&card->gdev->dev, "The qeth device driver failed to recover "

drivers/s390/net/qeth_core_mpc.c

@@ -249,6 +249,7 @@ static struct ipa_cmd_names qeth_ipa_cmd_names[] = {
 	{IPA_CMD_DELIP,		"delip"},
 	{IPA_CMD_SETADAPTERPARMS, "setadapterparms"},
 	{IPA_CMD_SET_DIAG_ASS,	"set_diag_ass"},
+	{IPA_CMD_SETBRIDGEPORT,	"set_bridge_port"},
 	{IPA_CMD_CREATE_ADDR,	"create_addr"},
 	{IPA_CMD_DESTROY_ADDR,	"destroy_addr"},
 	{IPA_CMD_REGISTER_LOCAL_ADDR,	"register_local_addr"},

drivers/s390/net/qeth_core_mpc.h

@@ -104,6 +104,7 @@ enum qeth_ipa_cmds {
 	IPA_CMD_DELIP			= 0xb7,
 	IPA_CMD_SETADAPTERPARMS		= 0xb8,
 	IPA_CMD_SET_DIAG_ASS		= 0xb9,
+	IPA_CMD_SETBRIDGEPORT		= 0xbe,
 	IPA_CMD_CREATE_ADDR		= 0xc3,
 	IPA_CMD_DESTROY_ADDR		= 0xc4,
 	IPA_CMD_REGISTER_LOCAL_ADDR	= 0xd1,
@@ -500,6 +501,88 @@ struct qeth_ipacmd_diagass {
 	__u8   cdata[64];
 } __attribute__ ((packed));
 
+/* SETBRIDGEPORT IPA Command:	 *********************************************/
+enum qeth_ipa_sbp_cmd {
+	IPA_SBP_QUERY_COMMANDS_SUPPORTED	= 0x00000000L,
+	IPA_SBP_RESET_BRIDGE_PORT_ROLE		= 0x00000001L,
+	IPA_SBP_SET_PRIMARY_BRIDGE_PORT		= 0x00000002L,
+	IPA_SBP_SET_SECONDARY_BRIDGE_PORT	= 0x00000004L,
+	IPA_SBP_QUERY_BRIDGE_PORTS		= 0x00000008L,
+	IPA_SBP_BRIDGE_PORT_STATE_CHANGE	= 0x00000010L,
+};
+
+struct net_if_token {
+	__u16 devnum;
+	__u8 cssid;
+	__u8 iid;
+	__u8 ssid;
+	__u8 chpid;
+	__u16 chid;
+} __packed;
+
+struct qeth_ipacmd_sbp_hdr {
+	__u32 supported_sbp_cmds;
+	__u32 enabled_sbp_cmds;
+	__u16 cmdlength;
+	__u16 reserved1;
+	__u32 command_code;
+	__u16 return_code;
+	__u8  used_total;
+	__u8  seq_no;
+	__u32 reserved2;
+} __packed;
+
+struct qeth_sbp_query_cmds_supp {
+	__u32 supported_cmds;
+	__u32 reserved;
+} __packed;
+
+struct qeth_sbp_reset_role {
+} __packed;
+
+struct qeth_sbp_set_primary {
+	struct net_if_token token;
+} __packed;
+
+struct qeth_sbp_set_secondary {
+} __packed;
+
+struct qeth_sbp_port_entry {
+		__u8 role;
+		__u8 state;
+		__u8 reserved1;
+		__u8 reserved2;
+		struct net_if_token token;
+} __packed;
+
+struct qeth_sbp_query_ports {
+	__u8 primary_bp_supported;
+	__u8 secondary_bp_supported;
+	__u8 num_entries;
+	__u8 entry_length;
+	struct qeth_sbp_port_entry entry[];
+} __packed;
+
+struct qeth_sbp_state_change {
+	__u8 primary_bp_supported;
+	__u8 secondary_bp_supported;
+	__u8 num_entries;
+	__u8 entry_length;
+	struct qeth_sbp_port_entry entry[];
+} __packed;
+
+struct qeth_ipacmd_setbridgeport {
+	struct qeth_ipacmd_sbp_hdr hdr;
+	union {
+		struct qeth_sbp_query_cmds_supp query_cmds_supp;
+		struct qeth_sbp_reset_role reset_role;
+		struct qeth_sbp_set_primary set_primary;
+		struct qeth_sbp_set_secondary set_secondary;
+		struct qeth_sbp_query_ports query_ports;
+		struct qeth_sbp_state_change state_change;
+	} data;
+} __packed;
+
 /* Header for each IPA command */
 struct qeth_ipacmd_hdr {
 	__u8   command;
@@ -529,6 +612,7 @@ struct qeth_ipa_cmd {
 		struct qeth_ipacmd_setadpparms		setadapterparms;
 		struct qeth_set_routing			setrtg;
 		struct qeth_ipacmd_diagass		diagass;
+		struct qeth_ipacmd_setbridgeport	sbp;
 	} data;
 } __attribute__ ((packed));
 

drivers/s390/net/qeth_l2.h

+/*
+ *    Copyright IBM Corp. 2013
+ *    Author(s): Eugene Crosser <eugene.crosser@ru.ibm.com>
+ */
+
+#ifndef __QETH_L2_H__
+#define __QETH_L2_H__
+
+#include "qeth_core.h"
+
+int qeth_l2_create_device_attributes(struct device *);
+void qeth_l2_remove_device_attributes(struct device *);
+void qeth_l2_setup_bridgeport_attrs(struct qeth_card *card);
+
+#endif /* __QETH_L2_H__ */

drivers/s390/net/qeth_l2_sys.c

+/*
+ *    Copyright IBM Corp. 2013
+ *    Author(s): Eugene Crosser <eugene.crosser@ru.ibm.com>
+ */
+
+#include <linux/slab.h>
+#include <asm/ebcdic.h>
+#include "qeth_l2.h"
+
+#define QETH_DEVICE_ATTR(_id, _name, _mode, _show, _store) \
+struct device_attribute dev_attr_##_id = __ATTR(_name, _mode, _show, _store)
+
+static int qeth_card_hw_is_reachable(struct qeth_card *card)
+{
+	return (card->state == CARD_STATE_SOFTSETUP) ||
+		(card->state == CARD_STATE_UP);
+}
+
+static ssize_t qeth_bridge_port_role_state_show(struct device *dev,
+				struct device_attribute *attr, char *buf,
+				int show_state)
+{
+	struct qeth_card *card = dev_get_drvdata(dev);
+	enum qeth_sbp_states state = QETH_SBP_STATE_INACTIVE;
+	int rc = 0;
+	char *word;
+
+	if (!card)
+		return -EINVAL;
+
+	mutex_lock(&card->conf_mutex);
+
+	if (qeth_card_hw_is_reachable(card) &&
+					card->options.sbp.supported_funcs)
+		rc = qeth_bridgeport_query_ports(card,
+			&card->options.sbp.role, &state);
+	if (!rc) {
+		if (show_state)
+			switch (state) {
+			case QETH_SBP_STATE_INACTIVE:
+				word = "inactive"; break;
+			case QETH_SBP_STATE_STANDBY:
+				word = "standby"; break;
+			case QETH_SBP_STATE_ACTIVE:
+				word = "active"; break;
+			default:
+				rc = -EIO;
+			}
+		else
+			switch (card->options.sbp.role) {
+			case QETH_SBP_ROLE_NONE:
+				word = "none"; break;
+			case QETH_SBP_ROLE_PRIMARY:
+				word = "primary"; break;
+			case QETH_SBP_ROLE_SECONDARY:
+				word = "secondary"; break;
+			default:
+				rc = -EIO;
+			}
+		if (rc)
+			QETH_CARD_TEXT_(card, 2, "SBP%02x:%02x",
+				card->options.sbp.role, state);
+		else
+			rc = sprintf(buf, "%s\n", word);
+	}
+
+	mutex_unlock(&card->conf_mutex);
+
+	return rc;
+}
+
+static ssize_t qeth_bridge_port_role_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	return qeth_bridge_port_role_state_show(dev, attr, buf, 0);
+}
+
+static ssize_t qeth_bridge_port_role_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct qeth_card *card = dev_get_drvdata(dev);
+	int rc = 0;
+	enum qeth_sbp_roles role;
+
+	if (!card)
+		return -EINVAL;
+	if (sysfs_streq(buf, "primary"))
+		role = QETH_SBP_ROLE_PRIMARY;
+	else if (sysfs_streq(buf, "secondary"))
+		role = QETH_SBP_ROLE_SECONDARY;
+	else if (sysfs_streq(buf, "none"))
+		role = QETH_SBP_ROLE_NONE;
+	else
+		return -EINVAL;
+
+	mutex_lock(&card->conf_mutex);
+
+	if (qeth_card_hw_is_reachable(card)) {
+		rc = qeth_bridgeport_setrole(card, role);
+		if (!rc)
+			card->options.sbp.role = role;
+	} else
+		card->options.sbp.role = role;
+
+	mutex_unlock(&card->conf_mutex);
+
+	return rc ? rc : count;
+}
+
+static DEVICE_ATTR(bridge_role, 0644, qeth_bridge_port_role_show,
+		   qeth_bridge_port_role_store);
+
+static ssize_t qeth_bridge_port_state_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	return qeth_bridge_port_role_state_show(dev, attr, buf, 1);
+}
+
+static DEVICE_ATTR(bridge_state, 0644, qeth_bridge_port_state_show,
+		   NULL);
+
+static struct attribute *qeth_l2_bridgeport_attrs[] = {
+	&dev_attr_bridge_role.attr,
+	&dev_attr_bridge_state.attr,
+	NULL,
+};
+
+static struct attribute_group qeth_l2_bridgeport_attr_group = {
+	.attrs = qeth_l2_bridgeport_attrs,
+};
+
+int qeth_l2_create_device_attributes(struct device *dev)
+{
+	return sysfs_create_group(&dev->kobj, &qeth_l2_bridgeport_attr_group);
+}
+
+void qeth_l2_remove_device_attributes(struct device *dev)
+{
+	sysfs_remove_group(&dev->kobj, &qeth_l2_bridgeport_attr_group);
+}
+
+/**
+ * qeth_l2_setup_bridgeport_attrs() - set/restore attrs when turning online.
+ * @card:			      qeth_card structure pointer
+ *
+ * Note: this function is called with conf_mutex held by the caller
+ */
+void qeth_l2_setup_bridgeport_attrs(struct qeth_card *card)
+{
+	if (!card)
+		return;
+	if (!card->options.sbp.supported_funcs)
+		return;
+	if (card->options.sbp.role != QETH_SBP_ROLE_NONE) {
+		/* Conditional to avoid spurious error messages */
+		qeth_bridgeport_setrole(card, card->options.sbp.role);
+		/* Let the callback function refresh the stored role value. */
+		qeth_bridgeport_query_ports(card,
+			&card->options.sbp.role, NULL);
+	}
+}