[PATCH 18/64] fcoe: fcoe_interface create, destroy and refcounting

Robert Love
2009-08-25T21:00:00Z

From: Chris Leech <christopher.leech@intel.com>

Up to this point the fcoe_instance structure was simply kzalloc/kfreed. This
patch introduces create and destroy functions as well as kref based reference
counting. The create function will grow as the initialization code is moved
there.

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
---

drivers/scsi/fcoe/fcoe.c | 97 +++++++++++++++++++++++++++++++++++++---------
drivers/scsi/fcoe/fcoe.h | 1
2 files changed, 79 insertions(+), 19 deletions(-)

diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 7f14c63..d1d6b3b 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -139,6 +139,58 @@ static struct scsi_host_template fcoe_shost_template = {
};

/**
+ * fcoe_interface_create()
+ * @netdev: network interface
+ *
+ * Returns: pointer to a struct fcoe_interface or NULL on error
+ */
+static struct fcoe_interface *fcoe_interface_create(struct net_device *netdev)
+{
+ struct fcoe_interface *fcoe;
+
+ fcoe = kzalloc(sizeof(*fcoe), GFP_KERNEL);
+ if (!fcoe) {
+ FCOE_NETDEV_DBG(netdev, "Could not allocate fcoe structure\n");
+ return NULL;
+ }
+
+ kref_init(&fcoe->kref);
+ fcoe->netdev = netdev;
+
+ return fcoe;
+}
+
+/**
+ * fcoe_interface_release() - fcoe_port kref release function
+ * @kref: embedded reference count in an fcoe_interface struct
+ */
+static void fcoe_interface_release(struct kref *kref)
+{
+ struct fcoe_interface *fcoe;
+
+ fcoe = container_of(kref, struct fcoe_interface, kref);
+ kfree(fcoe);
+}
+
+/**
+ * fcoe_interface_get()
+ * @fcoe:
+ */
+static inline void fcoe_interface_get(struct fcoe_interface *fcoe)
+{
+ kref_get(&fcoe->kref);
+}
+
+/**
+ * fcoe_interface_put()
+ * @fcoe:
+ */
+static inline void fcoe_interface_put(struct fcoe_interface *fcoe)
+{
+ kref_put(&fcoe->kref, fcoe_interface_release);
+}
+
+/**
* fcoe_fip_recv - handle a received FIP frame.
* @skb: the receive skb
* @dev: associated &net_device
@@ -558,7 +610,7 @@ static void fcoe_if_destroy(struct fc_lport *lport)
/* Release the net_device and Scsi_Host */
dev_put(netdev);
scsi_host_put(lport->host);
- kfree(fcoe); /* TODO, should be refcounted */
+ fcoe_interface_put(fcoe);
}

/*
@@ -604,8 +656,8 @@ static struct libfc_function_template fcoe_libfc_fcn_templ = {
};

/**
- * fcoe_if_create() - this function creates the fcoe interface
- * @netdev: pointer the associated netdevice
+ * fcoe_if_create() - this function creates the fcoe port
+ * @fcoe: fcoe_interface structure to create an fc_lport instance on
* @parent: device pointer to be the parent in sysfs for the SCSI host
*
* Creates fc_lport struct and scsi_host for lport, configures lport
@@ -613,30 +665,23 @@ static struct libfc_function_template fcoe_libfc_fcn_templ = {
*
* Returns : The allocated fc_lport or an error pointer
*/
-static struct fc_lport *fcoe_if_create(struct net_device *netdev,
+static struct fc_lport *fcoe_if_create(struct fcoe_interface *fcoe,
struct device *parent)
{
int rc;
struct fc_lport *lport = NULL;
struct fcoe_port *port;
- struct fcoe_interface *fcoe;
struct Scsi_Host *shost;
+ struct net_device *netdev = fcoe->netdev;

FCOE_NETDEV_DBG(netdev, "Create Interface\n");

- fcoe = kzalloc(sizeof(*fcoe), GFP_KERNEL);
- if (!fcoe) {
- FCOE_NETDEV_DBG(netdev, "Could not allocate fcoe structure\n");
- rc = -ENOMEM;
- goto out;
- }
-
shost = libfc_host_alloc(&fcoe_shost_template,
sizeof(struct fcoe_port));
if (!shost) {
FCOE_NETDEV_DBG(netdev, "Could not allocate host structure\n");
rc = -ENOMEM;
- goto out_kfree_port;
+ goto out;
}
lport = shost_priv(shost);
port = lport_priv(lport);
@@ -708,7 +753,7 @@ static struct fc_lport *fcoe_if_create(struct net_device *netdev,
fcoe_ctlr_link_up(&fcoe->ctlr);

dev_hold(netdev);
-
+ fcoe_interface_get(fcoe);
return lport;

out_lp_destroy:
@@ -717,8 +762,6 @@ out_netdev_cleanup:
fcoe_netdev_cleanup(port);
out_host_put:
scsi_host_put(lport->host);
-out_kfree_port:
- kfree(fcoe);
out:
return ERR_PTR(rc);
}
@@ -1620,6 +1663,8 @@ static int fcoe_ethdrv_put(const struct net_device *netdev)
static int fcoe_destroy(const char *buffer, struct kernel_param *kp)
{
struct net_device *netdev;
+ struct fcoe_interface *fcoe;
+ struct fcoe_port *port;
struct fc_lport *lport;
int rc;

@@ -1634,6 +1679,8 @@ static int fcoe_destroy(const char *buffer, struct kernel_param *kp)
rc = -ENODEV;
goto out_putdev;
}
+ port = lport_priv(lport);
+ fcoe = port->fcoe;
fcoe_if_destroy(lport);
fcoe_ethdrv_put(netdev);
rc = 0;
@@ -1653,6 +1700,7 @@ out_nodev:
static int fcoe_create(const char *buffer, struct kernel_param *kp)
{
int rc;
+ struct fcoe_interface *fcoe;
struct fc_lport *lport;
struct net_device *netdev;

@@ -1668,15 +1716,26 @@ static int fcoe_create(const char *buffer, struct kernel_param *kp)
}
fcoe_ethdrv_get(netdev);

- lport = fcoe_if_create(netdev, &netdev->dev);
+ fcoe = fcoe_interface_create(netdev);
+ if (!fcoe) {
+ rc = -ENOMEM;
+ goto out_putdev;
+ }
+
+ lport = fcoe_if_create(fcoe, &netdev->dev);
if (IS_ERR(lport)) {
printk(KERN_ERR "fcoe: Failed to create interface (%s)\n",
netdev->name);
fcoe_ethdrv_put(netdev);
rc = -EIO;
- goto out_putdev;
+ goto out_free;
}
- rc = 0;
+
+ dev_put(netdev);
+ return 0;
+
+out_free:
+ fcoe_interface_put(fcoe);
out_putdev:
dev_put(netdev);
out_nodev:
diff --git a/drivers/scsi/fcoe/fcoe.h b/drivers/scsi/fcoe/fcoe.h
index 673e70e..ff22928 100644
--- a/drivers/scsi/fcoe/fcoe.h
+++ b/drivers/scsi/fcoe/fcoe.h
@@ -84,6 +84,7 @@ struct fcoe_interface {
struct packet_type fip_packet_type;
struct fcoe_ctlr ctlr;
struct fc_exch_mgr *oem; /* offload exchange manager */
+ struct kref kref;
};

/*