[SCSI] iscsi class: sysfs group is_visible callout for iscsi host attrs

The iscsi class currently does not support writable sysfs
attrs for LLD sysfs settings. This patch converts the
iscsi class and driver's host attrs to use the attribute
container sysfs group and the sysfs group's is_visible callout
to be able to support readable or writable sysfs attrs.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

12 files changed, 94 insertions, 46 deletions

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
index 4f2411298b2..84e8c293a71 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.c
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -635,6 +635,15 @@ iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep)
 static mode_t iser_attr_is_visible(int param_type, int param)
 {
 	switch (param_type) {
+	case ISCSI_HOST_PARAM:
+		switch (param) {
+		case ISCSI_HOST_PARAM_NETDEV_NAME:
+		case ISCSI_HOST_PARAM_HWADDRESS:
+		case ISCSI_HOST_PARAM_INITIATOR_NAME:
+			return S_IRUGO;
+		default:
+			return 0;
+		}
 	case ISCSI_PARAM:
 		switch (param) {
 		case ISCSI_PARAM_MAX_RECV_DLENGTH:
@@ -697,9 +706,6 @@ static struct iscsi_transport iscsi_iser_transport = {
 	.owner                  = THIS_MODULE,
 	.name                   = "iser",
 	.caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T,
-	.host_param_mask	= ISCSI_HOST_HWADDRESS |
-				  ISCSI_HOST_NETDEV_NAME |
-				  ISCSI_HOST_INITIATOR_NAME,
 	/* session management */
 	.create_session         = iscsi_iser_session_create,
 	.destroy_session        = iscsi_iser_session_destroy,
diff --git a/drivers/scsi/be2iscsi/be_iscsi.c b/drivers/scsi/be2iscsi/be_iscsi.c
index ecd19bb3b20..feadaa28808 100644
--- a/drivers/scsi/be2iscsi/be_iscsi.c
+++ b/drivers/scsi/be2iscsi/be_iscsi.c
@@ -737,6 +737,15 @@ void beiscsi_ep_disconnect(struct iscsi_endpoint *ep)
 mode_t be2iscsi_attr_is_visible(int param_type, int param)
 {
 	switch (param_type) {
+	case ISCSI_HOST_PARAM:
+		switch (param) {
+		case ISCSI_HOST_PARAM_HWADDRESS:
+		case ISCSI_HOST_PARAM_IPADDRESS:
+		case ISCSI_HOST_PARAM_INITIATOR_NAME:
+			return S_IRUGO;
+		default:
+			return 0;
+		}
 	case ISCSI_PARAM:
 		switch (param) {
 		case ISCSI_PARAM_MAX_RECV_DLENGTH:
diff --git a/drivers/scsi/be2iscsi/be_main.c b/drivers/scsi/be2iscsi/be_main.c
index 93a3c708411..72ac64bbcea 100644
--- a/drivers/scsi/be2iscsi/be_main.c
+++ b/drivers/scsi/be2iscsi/be_main.c
@@ -4364,8 +4364,6 @@ struct iscsi_transport beiscsi_iscsi_transport = {
 	.name = DRV_NAME,
 	.caps = CAP_RECOVERY_L0 | CAP_HDRDGST | CAP_TEXT_NEGO |
 		CAP_MULTI_R2T | CAP_DATADGST | CAP_DATA_PATH_OFFLOAD,
-	.host_param_mask = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
-				ISCSI_HOST_INITIATOR_NAME,
 	.create_session = beiscsi_session_create,
 	.destroy_session = beiscsi_session_destroy,
 	.create_conn = beiscsi_conn_create,
diff --git a/drivers/scsi/bnx2i/bnx2i_iscsi.c b/drivers/scsi/bnx2i/bnx2i_iscsi.c
index 2db3399d273..d1e69719097 100644
--- a/drivers/scsi/bnx2i/bnx2i_iscsi.c
+++ b/drivers/scsi/bnx2i/bnx2i_iscsi.c
@@ -2180,6 +2180,15 @@ static int bnx2i_nl_set_path(struct Scsi_Host *shost, struct iscsi_path *params)
 static mode_t bnx2i_attr_is_visible(int param_type, int param)
 {
 	switch (param_type) {
+	case ISCSI_HOST_PARAM:
+		switch (param) {
+		case ISCSI_HOST_PARAM_NETDEV_NAME:
+		case ISCSI_HOST_PARAM_HWADDRESS:
+		case ISCSI_HOST_PARAM_IPADDRESS:
+			return S_IRUGO;
+		default:
+			return 0;
+		}
 	case ISCSI_PARAM:
 		switch (param) {
 		case ISCSI_PARAM_MAX_RECV_DLENGTH:
@@ -2251,8 +2260,6 @@ struct iscsi_transport bnx2i_iscsi_transport = {
 				  CAP_MULTI_R2T | CAP_DATADGST |
 				  CAP_DATA_PATH_OFFLOAD |
 				  CAP_TEXT_NEGO,
-	.host_param_mask	= ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
-				  ISCSI_HOST_NETDEV_NAME,
 	.create_session		= bnx2i_session_create,
 	.destroy_session	= bnx2i_session_destroy,
 	.create_conn		= bnx2i_conn_create,
diff --git a/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c b/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c
index 50d4e3f0503..f76185b010d 100644
--- a/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c
+++ b/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c
@@ -106,9 +106,6 @@ static struct iscsi_transport cxgb3i_iscsi_transport = {
 	.caps		= CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
 				| CAP_DATADGST | CAP_DIGEST_OFFLOAD |
 				CAP_PADDING_OFFLOAD | CAP_TEXT_NEGO,
-	.host_param_mask	= ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
-				ISCSI_HOST_INITIATOR_NAME |
-				ISCSI_HOST_NETDEV_NAME,
 	.attr_is_visible	= cxgbi_attr_is_visible,
 	.get_host_param	= cxgbi_get_host_param,
 	.set_host_param	= cxgbi_set_host_param,
diff --git a/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c b/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c
index 72f19ef7e01..628a6983a20 100644
--- a/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c
+++ b/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c
@@ -107,9 +107,6 @@ static struct iscsi_transport cxgb4i_iscsi_transport = {
 	.caps		= CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST |
 				CAP_DATADGST | CAP_DIGEST_OFFLOAD |
 				CAP_PADDING_OFFLOAD | CAP_TEXT_NEGO,
-	.host_param_mask	= ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
-				ISCSI_HOST_INITIATOR_NAME |
-				ISCSI_HOST_NETDEV_NAME,
 	.attr_is_visible	= cxgbi_attr_is_visible,
 	.get_host_param	= cxgbi_get_host_param,
 	.set_host_param	= cxgbi_set_host_param,
diff --git a/drivers/scsi/cxgbi/libcxgbi.c b/drivers/scsi/cxgbi/libcxgbi.c
index f9c2ca0d808..67ded44557e 100644
--- a/drivers/scsi/cxgbi/libcxgbi.c
+++ b/drivers/scsi/cxgbi/libcxgbi.c
@@ -2569,6 +2569,16 @@ EXPORT_SYMBOL_GPL(cxgbi_iscsi_cleanup);
 mode_t cxgbi_attr_is_visible(int param_type, int param)
 {
 	switch (param_type) {
+	case ISCSI_HOST_PARAM:
+		switch (param) {
+		case ISCSI_HOST_PARAM_NETDEV_NAME:
+		case ISCSI_HOST_PARAM_HWADDRESS:
+		case ISCSI_HOST_PARAM_IPADDRESS:
+		case ISCSI_HOST_PARAM_INITIATOR_NAME:
+			return S_IRUGO;
+		default:
+			return 0;
+		}
 	case ISCSI_PARAM:
 		switch (param) {
 		case ISCSI_PARAM_MAX_RECV_DLENGTH:
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 6ab21221176..23e706673d0 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -875,6 +875,16 @@ static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)
 static mode_t iscsi_sw_tcp_attr_is_visible(int param_type, int param)
 {
 	switch (param_type) {
+	case ISCSI_HOST_PARAM:
+		switch (param) {
+		case ISCSI_HOST_PARAM_NETDEV_NAME:
+		case ISCSI_HOST_PARAM_HWADDRESS:
+		case ISCSI_HOST_PARAM_IPADDRESS:
+		case ISCSI_HOST_PARAM_INITIATOR_NAME:
+			return S_IRUGO;
+		default:
+			return 0;
+		}
 	case ISCSI_PARAM:
 		switch (param) {
 		case ISCSI_PARAM_MAX_RECV_DLENGTH:
@@ -955,9 +965,6 @@ static struct iscsi_transport iscsi_sw_tcp_transport = {
 	.name			= "tcp",
 	.caps			= CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
 				  | CAP_DATADGST,
-	.host_param_mask	= ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
-				  ISCSI_HOST_INITIATOR_NAME |
-				  ISCSI_HOST_NETDEV_NAME,
 	/* session management */
 	.create_session		= iscsi_sw_tcp_session_create,
 	.destroy_session	= iscsi_sw_tcp_session_destroy,
diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index df6da3cb124..a9da3152ee5 100644
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -138,9 +138,6 @@ static struct iscsi_transport qla4xxx_iscsi_transport = {
 	.name			= DRIVER_NAME,
 	.caps			= CAP_FW_DB | CAP_SENDTARGETS_OFFLOAD |
 				  CAP_DATA_PATH_OFFLOAD,
-	.host_param_mask	= ISCSI_HOST_HWADDRESS |
-				  ISCSI_HOST_IPADDRESS |
-				  ISCSI_HOST_INITIATOR_NAME,
 	.tgt_dscvr		= qla4xxx_tgt_dscvr,
 	.attr_is_visible	= ql4_attr_is_visible,
 	.get_conn_param		= qla4xxx_conn_get_param,
@@ -156,6 +153,15 @@ static struct scsi_transport_template *qla4xxx_scsi_transport;
 static mode_t ql4_attr_is_visible(int param_type, int param)
 {
 	switch (param_type) {
+	case ISCSI_HOST_PARAM:
+		switch (param) {
+		case ISCSI_HOST_PARAM_HWADDRESS:
+		case ISCSI_HOST_PARAM_IPADDRESS:
+		case ISCSI_HOST_PARAM_INITIATOR_NAME:
+			return S_IRUGO;
+		default:
+			return 0;
+		}
 	case ISCSI_PARAM:
 		switch (param) {
 		case ISCSI_PARAM_CONN_ADDRESS:
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index a8dd85dc77b..2e9b6821559 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -32,8 +32,6 @@
 #include <scsi/iscsi_if.h>
 #include <scsi/scsi_cmnd.h>
 
-#define ISCSI_HOST_ATTRS 4
-
 #define ISCSI_TRANSPORT_VERSION "2.0-870"
 
 static int dbg_session;
@@ -74,7 +72,6 @@ struct iscsi_internal {
 	struct list_head list;
 	struct device dev;
 
-	struct device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
 	struct transport_container conn_cont;
 	struct transport_container session_cont;
 };
@@ -2301,13 +2298,42 @@ iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
 
-#define SETUP_HOST_RD_ATTR(field, param_flag)				\
-do {									\
-	if (tt->host_param_mask & param_flag) {				\
-		priv->host_attrs[count] = &dev_attr_host_##field; \
-		count++;						\
-	}								\
-} while (0)
+static struct attribute *iscsi_host_attrs[] = {
+	&dev_attr_host_netdev.attr,
+	&dev_attr_host_hwaddress.attr,
+	&dev_attr_host_ipaddress.attr,
+	&dev_attr_host_initiatorname.attr,
+	NULL,
+};
+
+static mode_t iscsi_host_attr_is_visible(struct kobject *kobj,
+					 struct attribute *attr, int i)
+{
+	struct device *cdev = container_of(kobj, struct device, kobj);
+	struct Scsi_Host *shost = transport_class_to_shost(cdev);
+	struct iscsi_internal *priv = to_iscsi_internal(shost->transportt);
+	int param;
+
+	if (attr == &dev_attr_host_netdev.attr)
+		param = ISCSI_HOST_PARAM_NETDEV_NAME;
+	else if (attr == &dev_attr_host_hwaddress.attr)
+		param = ISCSI_HOST_PARAM_HWADDRESS;
+	else if (attr == &dev_attr_host_ipaddress.attr)
+		param = ISCSI_HOST_PARAM_IPADDRESS;
+	else if (attr == &dev_attr_host_initiatorname.attr)
+		param = ISCSI_HOST_PARAM_INITIATOR_NAME;
+	else {
+		WARN_ONCE(1, "Invalid host attr");
+		return 0;
+	}
+
+	return priv->iscsi_transport->attr_is_visible(ISCSI_HOST_PARAM, param);
+}
+
+static struct attribute_group iscsi_host_group = {
+	.attrs = iscsi_host_attrs,
+	.is_visible = iscsi_host_attr_is_visible,
+};
 
 static int iscsi_session_match(struct attribute_container *cont,
 			   struct device *dev)
@@ -2379,7 +2405,7 @@ iscsi_register_transport(struct iscsi_transport *tt)
 {
 	struct iscsi_internal *priv;
 	unsigned long flags;
-	int count = 0, err;
+	int err;
 
 	BUG_ON(!tt);
 
@@ -2406,20 +2432,12 @@ iscsi_register_transport(struct iscsi_transport *tt)
 		goto unregister_dev;
 
 	/* host parameters */
-	priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
 	priv->t.host_attrs.ac.class = &iscsi_host_class.class;
 	priv->t.host_attrs.ac.match = iscsi_host_match;
+	priv->t.host_attrs.ac.grp = &iscsi_host_group;
 	priv->t.host_size = sizeof(struct iscsi_cls_host);
 	transport_container_register(&priv->t.host_attrs);
 
-	SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
-	SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
-	SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
-	SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
-	BUG_ON(count > ISCSI_HOST_ATTRS);
-	priv->host_attrs[count] = NULL;
-	count = 0;
-
 	/* connection parameters */
 	priv->conn_cont.ac.class = &iscsi_connection_class.class;
 	priv->conn_cont.ac.match = iscsi_conn_match;
diff --git a/include/scsi/iscsi_if.h b/include/scsi/iscsi_if.h
index 164a753fdd3..3753f7e3638 100644
--- a/include/scsi/iscsi_if.h
+++ b/include/scsi/iscsi_if.h
@@ -391,11 +391,6 @@ enum iscsi_host_param {
 	ISCSI_HOST_PARAM_MAX,
 };
 
-#define ISCSI_HOST_HWADDRESS		(1ULL << ISCSI_HOST_PARAM_HWADDRESS)
-#define ISCSI_HOST_INITIATOR_NAME	(1ULL << ISCSI_HOST_PARAM_INITIATOR_NAME)
-#define ISCSI_HOST_NETDEV_NAME		(1ULL << ISCSI_HOST_PARAM_NETDEV_NAME)
-#define ISCSI_HOST_IPADDRESS		(1ULL << ISCSI_HOST_PARAM_IPADDRESS)
-
 #define iscsi_ptr(_handle) ((void*)(unsigned long)_handle)
 #define iscsi_handle(_ptr) ((uint64_t)(unsigned long)_ptr)
 
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index b9e9ef5a881..77e6dd60fb4 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -85,8 +85,6 @@ struct iscsi_transport {
 	struct module *owner;
 	char *name;
 	unsigned int caps;
-	/* LLD sets this to indicate what values it can export to sysfs */
-	uint64_t host_param_mask;
 
 	struct iscsi_cls_session *(*create_session) (struct iscsi_endpoint *ep,
 					uint16_t cmds_max, uint16_t qdepth,