Re: [PATCH 1/4 2.6.28] cxgb3 - manage a private ip address for iSCSI

[PATCH 1/4 2.6.28] cxgb3 - manage a private ip address for iSCSI

From: Karen Xie <redacted>

Create a per port sysfs entry to pass an IP address to the NIC driver, and a control call for the iSCSI driver to grab it.
The IP address is required in both drivers to manage ARP requests and connection set up.

Signed-off-by: Divy Le Ray <redacted>
---

 drivers/net/cxgb3/adapter.h        |    1 +
 drivers/net/cxgb3/cxgb3_ctl_defs.h |    7 ++++
 drivers/net/cxgb3/cxgb3_main.c     |   65 ++++++++++++++++++++++++++++++++++++
 drivers/net/cxgb3/cxgb3_offload.c  |    6 +++
 4 files changed, 79 insertions(+), 0 deletions(-)

diff --git a/drivers/net/cxgb3/adapter.h b/drivers/net/cxgb3/adapter.h
index 2711404..0e4fe95 100644
--- a/drivers/net/cxgb3/adapter.h
+++ b/drivers/net/cxgb3/adapter.h

@@ -64,6 +64,7 @@ struct port_info {
 	struct link_config link_config;
 	struct net_device_stats netstats;
 	int activity;
+	__be32 iscsi_ipaddr;
 };
 
 enum {				/* adapter flags */

diff --git a/drivers/net/cxgb3/cxgb3_ctl_defs.h b/drivers/net/cxgb3/cxgb3_ctl_defs.h
index 6ad9240..e171aa8 100644
--- a/drivers/net/cxgb3/cxgb3_ctl_defs.h
+++ b/drivers/net/cxgb3/cxgb3_ctl_defs.h

@@ -57,6 +57,7 @@ enum {
 	RDMA_GET_MIB		= 19,
 
 	GET_RX_PAGE_INFO	= 50,
+	GET_ISCSI_IPADDR	= 51,
 };
 
 /*

@@ -86,6 +87,12 @@ struct iff_mac {
 	u16 vlan_tag;
 };
 
+/* Structure used to request a port's iSCSI IP address */
+struct iscsi_ipaddr {
+	struct net_device *dev;		/* the net_device */
+	__be32 ipaddr;			/* the return iSCSI IP address */
+};
+
 struct pci_dev;
 
 /*

diff --git a/drivers/net/cxgb3/cxgb3_main.c b/drivers/net/cxgb3/cxgb3_main.c
index 5447f3e..1c8952c 100644
--- a/drivers/net/cxgb3/cxgb3_main.c
+++ b/drivers/net/cxgb3/cxgb3_main.c

@@ -687,6 +687,66 @@ static struct attribute *offload_attrs[] = {
 
 static struct attribute_group offload_attr_group = {.attrs = offload_attrs };
 
+static ssize_t iscsi_ipaddr_attr_show(struct device *d,
+				      char *buf)

+#define ISCSI_IPADDR_ATTR(name) \
+static ssize_t show_##name(struct device *d, struct device_attribute *attr, \
+			   char *buf) \
+{ \
+	return iscsi_ipaddr_attr_show(d, buf); \
+} \
+static ssize_t store_##name(struct device *d, struct device_attribute *attr, \
+                            const char *buf, size_t len) \
+{ \
+	return iscsi_ipaddr_attr_store(d, buf, len); \
+} \
+static DEVICE_ATTR(name, S_IRUGO | S_IWUSR, show_##name, store_##name)
+
+ISCSI_IPADDR_ATTR(iscsi_ipaddr);
+
+static struct attribute *iscsi_offload_attrs[] = {
+	&dev_attr_iscsi_ipaddr.attr,
+	NULL
+};
+
+static struct attribute_group iscsi_offload_attr_group = {
+        .attrs = iscsi_offload_attrs
+};
+
 /*
  * Sends an sk_buff to an offload queue driver
  * after dealing with any active network taps.

@@ -1078,6 +1138,7 @@ static int cxgb_open(struct net_device *dev)
 		if (err)
 			printk(KERN_WARNING
 			       "Could not initialize offload capabilities\n");
+		sysfs_create_group(&dev->dev.kobj, &iscsi_offload_attr_group);
 	}
 
 	link_start(dev);

@@ -1100,6 +1161,9 @@ static int cxgb_close(struct net_device *dev)
 	netif_carrier_off(dev);
 	t3_mac_disable(&pi->mac, MAC_DIRECTION_TX | MAC_DIRECTION_RX);
 
+        if (is_offload(adapter) && !ofld_disable)
+		sysfs_remove_group(&dev->dev.kobj, &iscsi_offload_attr_group);
+
 	spin_lock(&adapter->work_lock);	/* sync with update task */
 	clear_bit(pi->port_id, &adapter->open_device_map);
 	spin_unlock(&adapter->work_lock);

@@ -2681,6 +2745,7 @@ static int __devinit init_one(struct pci_dev *pdev,
 		pi->first_qset = i;
 		pi->activity = 0;
 		pi->port_id = i;
+		pi->iscsi_ipaddr = 0;
 		netif_carrier_off(netdev);
 		netdev->irq = pdev->irq;
 		netdev->mem_start = mmio_start;

diff --git a/drivers/net/cxgb3/cxgb3_offload.c b/drivers/net/cxgb3/cxgb3_offload.c
index c5b3de1..d5687dc 100644
--- a/drivers/net/cxgb3/cxgb3_offload.c
+++ b/drivers/net/cxgb3/cxgb3_offload.c

@@ -407,6 +407,12 @@ static int cxgb_offload_ctl(struct t3cdev *tdev, unsigned int req, void *data)
 		rx_page_info->page_size = tp->rx_pg_size;
 		rx_page_info->num = tp->rx_num_pgs;
 		break;
+	case GET_ISCSI_IPADDR: {
+		struct iscsi_ipaddr *p = data;
+		struct port_info *pi = netdev_priv(p->dev);
+		p->ipaddr = pi->iscsi_ipaddr;
+		break;
+	}
 	default:
 		return -EOPNOTSUPP;
 	}