Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1059 insertions, 0 deletions

diff --git a/drivers/scsi/fcoe/fcoe_transport.c b/drivers/scsi/fcoe/fcoe_transport.c
new file mode 100644
index 000000000..62341c635
--- /dev/null
+++ b/drivers/scsi/fcoe/fcoe_transport.c
@@ -0,0 +1,1059 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/netdevice.h>
+#include <linux/ethtool.h>
+#include <linux/errno.h>
+#include <linux/crc32.h>
+#include <scsi/libfcoe.h>
+
+#include "libfcoe.h"
+
+MODULE_AUTHOR("Open-FCoE.org");
+MODULE_DESCRIPTION("FIP discovery protocol and FCoE transport for FCoE HBAs");
+MODULE_LICENSE("GPL v2");
+
+static int fcoe_transport_create(const char *, const struct kernel_param *);
+static int fcoe_transport_destroy(const char *, const struct kernel_param *);
+static int fcoe_transport_show(char *buffer, const struct kernel_param *kp);
+static struct fcoe_transport *fcoe_transport_lookup(struct net_device *device);
+static struct fcoe_transport *fcoe_netdev_map_lookup(struct net_device *device);
+static int fcoe_transport_enable(const char *, const struct kernel_param *);
+static int fcoe_transport_disable(const char *, const struct kernel_param *);
+static int libfcoe_device_notification(struct notifier_block *notifier,
+				    ulong event, void *ptr);
+
+static LIST_HEAD(fcoe_transports);
+static DEFINE_MUTEX(ft_mutex);
+static LIST_HEAD(fcoe_netdevs);
+static DEFINE_MUTEX(fn_mutex);
+
+unsigned int libfcoe_debug_logging;
+module_param_named(debug_logging, libfcoe_debug_logging, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
+
+module_param_call(show, NULL, fcoe_transport_show, NULL, S_IRUSR);
+__MODULE_PARM_TYPE(show, "string");
+MODULE_PARM_DESC(show, " Show attached FCoE transports");
+
+module_param_call(create, fcoe_transport_create, NULL,
+		  (void *)FIP_MODE_FABRIC, S_IWUSR);
+__MODULE_PARM_TYPE(create, "string");
+MODULE_PARM_DESC(create, " Creates fcoe instance on an ethernet interface");
+
+module_param_call(create_vn2vn, fcoe_transport_create, NULL,
+		  (void *)FIP_MODE_VN2VN, S_IWUSR);
+__MODULE_PARM_TYPE(create_vn2vn, "string");
+MODULE_PARM_DESC(create_vn2vn, " Creates a VN_node to VN_node FCoE instance "
+		 "on an Ethernet interface");
+
+module_param_call(destroy, fcoe_transport_destroy, NULL, NULL, S_IWUSR);
+__MODULE_PARM_TYPE(destroy, "string");
+MODULE_PARM_DESC(destroy, " Destroys fcoe instance on an ethernet interface");
+
+module_param_call(enable, fcoe_transport_enable, NULL, NULL, S_IWUSR);
+__MODULE_PARM_TYPE(enable, "string");
+MODULE_PARM_DESC(enable, " Enables fcoe on an ethernet interface.");
+
+module_param_call(disable, fcoe_transport_disable, NULL, NULL, S_IWUSR);
+__MODULE_PARM_TYPE(disable, "string");
+MODULE_PARM_DESC(disable, " Disables fcoe on an ethernet interface.");
+
+/* notification function for packets from net device */
+static struct notifier_block libfcoe_notifier = {
+	.notifier_call = libfcoe_device_notification,
+};
+
+static const struct {
+	u32 fc_port_speed;
+#define SPEED_2000	2000
+#define SPEED_4000	4000
+#define SPEED_8000	8000
+#define SPEED_16000	16000
+#define SPEED_32000	32000
+	u32 eth_port_speed;
+} fcoe_port_speed_mapping[] = {
+	{ FC_PORTSPEED_1GBIT,   SPEED_1000   },
+	{ FC_PORTSPEED_2GBIT,   SPEED_2000   },
+	{ FC_PORTSPEED_4GBIT,   SPEED_4000   },
+	{ FC_PORTSPEED_8GBIT,   SPEED_8000   },
+	{ FC_PORTSPEED_10GBIT,  SPEED_10000  },
+	{ FC_PORTSPEED_16GBIT,  SPEED_16000  },
+	{ FC_PORTSPEED_20GBIT,  SPEED_20000  },
+	{ FC_PORTSPEED_25GBIT,  SPEED_25000  },
+	{ FC_PORTSPEED_32GBIT,  SPEED_32000  },
+	{ FC_PORTSPEED_40GBIT,  SPEED_40000  },
+	{ FC_PORTSPEED_50GBIT,  SPEED_50000  },
+	{ FC_PORTSPEED_100GBIT, SPEED_100000 },
+};
+
+static inline u32 eth2fc_speed(u32 eth_port_speed)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(fcoe_port_speed_mapping); i++) {
+		if (fcoe_port_speed_mapping[i].eth_port_speed == eth_port_speed)
+			return fcoe_port_speed_mapping[i].fc_port_speed;
+	}
+
+	return FC_PORTSPEED_UNKNOWN;
+}
+
+/**
+ * fcoe_link_speed_update() - Update the supported and actual link speeds
+ * @lport: The local port to update speeds for
+ *
+ * Returns: 0 if the ethtool query was successful
+ *          -1 if the ethtool query failed
+ */
+int fcoe_link_speed_update(struct fc_lport *lport)
+{
+	struct net_device *netdev = fcoe_get_netdev(lport);
+	struct ethtool_link_ksettings ecmd;
+
+	if (!__ethtool_get_link_ksettings(netdev, &ecmd)) {
+		lport->link_supported_speeds &= ~(FC_PORTSPEED_1GBIT  |
+		                                  FC_PORTSPEED_10GBIT |
+		                                  FC_PORTSPEED_20GBIT |
+		                                  FC_PORTSPEED_40GBIT);
+
+		if (ecmd.link_modes.supported[0] & (
+			    SUPPORTED_1000baseT_Half |
+			    SUPPORTED_1000baseT_Full |
+			    SUPPORTED_1000baseKX_Full))
+			lport->link_supported_speeds |= FC_PORTSPEED_1GBIT;
+
+		if (ecmd.link_modes.supported[0] & (
+			    SUPPORTED_10000baseT_Full   |
+			    SUPPORTED_10000baseKX4_Full |
+			    SUPPORTED_10000baseKR_Full  |
+			    SUPPORTED_10000baseR_FEC))
+			lport->link_supported_speeds |= FC_PORTSPEED_10GBIT;
+
+		if (ecmd.link_modes.supported[0] & (
+			    SUPPORTED_20000baseMLD2_Full |
+			    SUPPORTED_20000baseKR2_Full))
+			lport->link_supported_speeds |= FC_PORTSPEED_20GBIT;
+
+		if (ecmd.link_modes.supported[0] & (
+			    SUPPORTED_40000baseKR4_Full |
+			    SUPPORTED_40000baseCR4_Full |
+			    SUPPORTED_40000baseSR4_Full |
+			    SUPPORTED_40000baseLR4_Full))
+			lport->link_supported_speeds |= FC_PORTSPEED_40GBIT;
+
+		lport->link_speed = eth2fc_speed(ecmd.base.speed);
+		return 0;
+	}
+	return -1;
+}
+EXPORT_SYMBOL_GPL(fcoe_link_speed_update);
+
+/**
+ * __fcoe_get_lesb() - Get the Link Error Status Block (LESB) for a given lport
+ * @lport: The local port to update speeds for
+ * @fc_lesb: Pointer to the LESB to be filled up
+ * @netdev: Pointer to the netdev that is associated with the lport
+ *
+ * Note, the Link Error Status Block (LESB) for FCoE is defined in FC-BB-6
+ * Clause 7.11 in v1.04.
+ */
+void __fcoe_get_lesb(struct fc_lport *lport,
+		     struct fc_els_lesb *fc_lesb,
+		     struct net_device *netdev)
+{
+	unsigned int cpu;
+	u32 lfc, vlfc, mdac;
+	struct fc_stats *stats;
+	struct fcoe_fc_els_lesb *lesb;
+	struct rtnl_link_stats64 temp;
+
+	lfc = 0;
+	vlfc = 0;
+	mdac = 0;
+	lesb = (struct fcoe_fc_els_lesb *)fc_lesb;
+	memset(lesb, 0, sizeof(*lesb));
+	for_each_possible_cpu(cpu) {
+		stats = per_cpu_ptr(lport->stats, cpu);
+		lfc += READ_ONCE(stats->LinkFailureCount);
+		vlfc += READ_ONCE(stats->VLinkFailureCount);
+		mdac += READ_ONCE(stats->MissDiscAdvCount);
+	}
+	lesb->lesb_link_fail = htonl(lfc);
+	lesb->lesb_vlink_fail = htonl(vlfc);
+	lesb->lesb_miss_fka = htonl(mdac);
+	lesb->lesb_fcs_error =
+			htonl(dev_get_stats(netdev, &temp)->rx_crc_errors);
+}
+EXPORT_SYMBOL_GPL(__fcoe_get_lesb);
+
+/**
+ * fcoe_get_lesb() - Fill the FCoE Link Error Status Block
+ * @lport: the local port
+ * @fc_lesb: the link error status block
+ */
+void fcoe_get_lesb(struct fc_lport *lport,
+			 struct fc_els_lesb *fc_lesb)
+{
+	struct net_device *netdev = fcoe_get_netdev(lport);
+
+	__fcoe_get_lesb(lport, fc_lesb, netdev);
+}
+EXPORT_SYMBOL_GPL(fcoe_get_lesb);
+
+/**
+ * fcoe_ctlr_get_lesb() - Get the Link Error Status Block (LESB) for a given
+ * fcoe controller device
+ * @ctlr_dev: The given fcoe controller device
+ *
+ */
+void fcoe_ctlr_get_lesb(struct fcoe_ctlr_device *ctlr_dev)
+{
+	struct fcoe_ctlr *fip = fcoe_ctlr_device_priv(ctlr_dev);
+	struct net_device *netdev = fcoe_get_netdev(fip->lp);
+	struct fc_els_lesb *fc_lesb;
+
+	fc_lesb = (struct fc_els_lesb *)(&ctlr_dev->lesb);
+	__fcoe_get_lesb(fip->lp, fc_lesb, netdev);
+}
+EXPORT_SYMBOL_GPL(fcoe_ctlr_get_lesb);
+
+void fcoe_wwn_to_str(u64 wwn, char *buf, int len)
+{
+	u8 wwpn[8];
+
+	u64_to_wwn(wwn, wwpn);
+	snprintf(buf, len, "%02x%02x%02x%02x%02x%02x%02x%02x",
+		 wwpn[0], wwpn[1], wwpn[2], wwpn[3],
+		 wwpn[4], wwpn[5], wwpn[6], wwpn[7]);
+}
+EXPORT_SYMBOL_GPL(fcoe_wwn_to_str);
+
+/**
+ * fcoe_validate_vport_create() - Validate a vport before creating it
+ * @vport: NPIV port to be created
+ *
+ * This routine is meant to add validation for a vport before creating it
+ * via fcoe_vport_create().
+ * Current validations are:
+ *      - WWPN supplied is unique for given lport
+ */
+int fcoe_validate_vport_create(struct fc_vport *vport)
+{
+	struct Scsi_Host *shost = vport_to_shost(vport);
+	struct fc_lport *n_port = shost_priv(shost);
+	struct fc_lport *vn_port;
+	int rc = 0;
+	char buf[32];
+
+	mutex_lock(&n_port->lp_mutex);
+
+	fcoe_wwn_to_str(vport->port_name, buf, sizeof(buf));
+	/* Check if the wwpn is not same as that of the lport */
+	if (!memcmp(&n_port->wwpn, &vport->port_name, sizeof(u64))) {
+		LIBFCOE_TRANSPORT_DBG("vport WWPN 0x%s is same as that of the "
+				      "base port WWPN\n", buf);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	/* Check if there is any existing vport with same wwpn */
+	list_for_each_entry(vn_port, &n_port->vports, list) {
+		if (!memcmp(&vn_port->wwpn, &vport->port_name, sizeof(u64))) {
+			LIBFCOE_TRANSPORT_DBG("vport with given WWPN 0x%s "
+					      "already exists\n", buf);
+			rc = -EINVAL;
+			break;
+		}
+	}
+out:
+	mutex_unlock(&n_port->lp_mutex);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(fcoe_validate_vport_create);
+
+/**
+ * fcoe_get_wwn() - Get the world wide name from LLD if it supports it
+ * @netdev: the associated net device
+ * @wwn: the output WWN
+ * @type: the type of WWN (WWPN or WWNN)
+ *
+ * Returns: 0 for success
+ */
+int fcoe_get_wwn(struct net_device *netdev, u64 *wwn, int type)
+{
+	const struct net_device_ops *ops = netdev->netdev_ops;
+
+	if (ops->ndo_fcoe_get_wwn)
+		return ops->ndo_fcoe_get_wwn(netdev, wwn, type);
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(fcoe_get_wwn);
+
+/**
+ * fcoe_fc_crc() - Calculates the CRC for a given frame
+ * @fp: The frame to be checksumed
+ *
+ * This uses crc32() routine to calculate the CRC for a frame
+ *
+ * Return: The 32 bit CRC value
+ */
+u32 fcoe_fc_crc(struct fc_frame *fp)
+{
+	struct sk_buff *skb = fp_skb(fp);
+	skb_frag_t *frag;
+	unsigned char *data;
+	unsigned long off, len, clen;
+	u32 crc;
+	unsigned i;
+
+	crc = crc32(~0, skb->data, skb_headlen(skb));
+
+	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+		frag = &skb_shinfo(skb)->frags[i];
+		off = skb_frag_off(frag);
+		len = skb_frag_size(frag);
+		while (len > 0) {
+			clen = min(len, PAGE_SIZE - (off & ~PAGE_MASK));
+			data = kmap_atomic(
+				skb_frag_page(frag) + (off >> PAGE_SHIFT));
+			crc = crc32(crc, data + (off & ~PAGE_MASK), clen);
+			kunmap_atomic(data);
+			off += clen;
+			len -= clen;
+		}
+	}
+	return crc;
+}
+EXPORT_SYMBOL_GPL(fcoe_fc_crc);
+
+/**
+ * fcoe_start_io() - Start FCoE I/O
+ * @skb: The packet to be transmitted
+ *
+ * This routine is called from the net device to start transmitting
+ * FCoE packets.
+ *
+ * Returns: 0 for success
+ */
+int fcoe_start_io(struct sk_buff *skb)
+{
+	struct sk_buff *nskb;
+	int rc;
+
+	nskb = skb_clone(skb, GFP_ATOMIC);
+	if (!nskb)
+		return -ENOMEM;
+	rc = dev_queue_xmit(nskb);
+	if (rc != 0)
+		return rc;
+	kfree_skb(skb);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fcoe_start_io);
+
+
+/**
+ * fcoe_clean_pending_queue() - Dequeue a skb and free it
+ * @lport: The local port to dequeue a skb on
+ */
+void fcoe_clean_pending_queue(struct fc_lport *lport)
+{
+	struct fcoe_port  *port = lport_priv(lport);
+	struct sk_buff *skb;
+
+	spin_lock_bh(&port->fcoe_pending_queue.lock);
+	while ((skb = __skb_dequeue(&port->fcoe_pending_queue)) != NULL) {
+		spin_unlock_bh(&port->fcoe_pending_queue.lock);
+		kfree_skb(skb);
+		spin_lock_bh(&port->fcoe_pending_queue.lock);
+	}
+	spin_unlock_bh(&port->fcoe_pending_queue.lock);
+}
+EXPORT_SYMBOL_GPL(fcoe_clean_pending_queue);
+
+/**
+ * fcoe_check_wait_queue() - Attempt to clear the transmit backlog
+ * @lport: The local port whose backlog is to be cleared
+ * @skb: The received FIP packet
+ *
+ * This empties the wait_queue, dequeues the head of the wait_queue queue
+ * and calls fcoe_start_io() for each packet. If all skb have been
+ * transmitted it returns the qlen. If an error occurs it restores
+ * wait_queue (to try again later) and returns -1.
+ *
+ * The wait_queue is used when the skb transmit fails. The failed skb
+ * will go in the wait_queue which will be emptied by the timer function or
+ * by the next skb transmit.
+ */
+void fcoe_check_wait_queue(struct fc_lport *lport, struct sk_buff *skb)
+{
+	struct fcoe_port *port = lport_priv(lport);
+	int rc;
+
+	spin_lock_bh(&port->fcoe_pending_queue.lock);
+
+	if (skb)
+		__skb_queue_tail(&port->fcoe_pending_queue, skb);
+
+	if (port->fcoe_pending_queue_active)
+		goto out;
+	port->fcoe_pending_queue_active = 1;
+
+	while (port->fcoe_pending_queue.qlen) {
+		/* keep qlen > 0 until fcoe_start_io succeeds */
+		port->fcoe_pending_queue.qlen++;
+		skb = __skb_dequeue(&port->fcoe_pending_queue);
+
+		spin_unlock_bh(&port->fcoe_pending_queue.lock);
+		rc = fcoe_start_io(skb);
+		spin_lock_bh(&port->fcoe_pending_queue.lock);
+
+		if (rc) {
+			__skb_queue_head(&port->fcoe_pending_queue, skb);
+			/* undo temporary increment above */
+			port->fcoe_pending_queue.qlen--;
+			break;
+		}
+		/* undo temporary increment above */
+		port->fcoe_pending_queue.qlen--;
+	}
+
+	if (port->fcoe_pending_queue.qlen < port->min_queue_depth)
+		lport->qfull = 0;
+	if (port->fcoe_pending_queue.qlen && !timer_pending(&port->timer))
+		mod_timer(&port->timer, jiffies + 2);
+	port->fcoe_pending_queue_active = 0;
+out:
+	if (port->fcoe_pending_queue.qlen > port->max_queue_depth)
+		lport->qfull = 1;
+	spin_unlock_bh(&port->fcoe_pending_queue.lock);
+}
+EXPORT_SYMBOL_GPL(fcoe_check_wait_queue);
+
+/**
+ * fcoe_queue_timer() - The fcoe queue timer
+ * @t: Timer context use to obtain the FCoE port
+ *
+ * Calls fcoe_check_wait_queue on timeout
+ */
+void fcoe_queue_timer(struct timer_list *t)
+{
+	struct fcoe_port *port = from_timer(port, t, timer);
+
+	fcoe_check_wait_queue(port->lport, NULL);
+}
+EXPORT_SYMBOL_GPL(fcoe_queue_timer);
+
+/**
+ * fcoe_get_paged_crc_eof() - Allocate a page to be used for the trailer CRC
+ * @skb:  The packet to be transmitted
+ * @tlen: The total length of the trailer
+ * @fps:  The fcoe context
+ *
+ * This routine allocates a page for frame trailers. The page is re-used if
+ * there is enough room left on it for the current trailer. If there isn't
+ * enough buffer left a new page is allocated for the trailer. Reference to
+ * the page from this function as well as the skbs using the page fragments
+ * ensure that the page is freed at the appropriate time.
+ *
+ * Returns: 0 for success
+ */
+int fcoe_get_paged_crc_eof(struct sk_buff *skb, int tlen,
+			   struct fcoe_percpu_s *fps)
+{
+	struct page *page;
+
+	page = fps->crc_eof_page;
+	if (!page) {
+		page = alloc_page(GFP_ATOMIC);
+		if (!page)
+			return -ENOMEM;
+
+		fps->crc_eof_page = page;
+		fps->crc_eof_offset = 0;
+	}
+
+	get_page(page);
+	skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, page,
+			   fps->crc_eof_offset, tlen);
+	skb->len += tlen;
+	skb->data_len += tlen;
+	skb->truesize += tlen;
+	fps->crc_eof_offset += sizeof(struct fcoe_crc_eof);
+
+	if (fps->crc_eof_offset >= PAGE_SIZE) {
+		fps->crc_eof_page = NULL;
+		fps->crc_eof_offset = 0;
+		put_page(page);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fcoe_get_paged_crc_eof);
+
+/**
+ * fcoe_transport_lookup - find an fcoe transport that matches a netdev
+ * @netdev: The netdev to look for from all attached transports
+ *
+ * Returns : ptr to the fcoe transport that supports this netdev or NULL
+ * if not found.
+ *
+ * The ft_mutex should be held when this is called
+ */
+static struct fcoe_transport *fcoe_transport_lookup(struct net_device *netdev)
+{
+	struct fcoe_transport *ft = NULL;
+
+	list_for_each_entry(ft, &fcoe_transports, list)
+		if (ft->match && ft->match(netdev))
+			return ft;
+	return NULL;
+}
+
+/**
+ * fcoe_transport_attach - Attaches an FCoE transport
+ * @ft: The fcoe transport to be attached
+ *
+ * Returns : 0 for success
+ */
+int fcoe_transport_attach(struct fcoe_transport *ft)
+{
+	int rc = 0;
+
+	mutex_lock(&ft_mutex);
+	if (ft->attached) {
+		LIBFCOE_TRANSPORT_DBG("transport %s already attached\n",
+				       ft->name);
+		rc = -EEXIST;
+		goto out_attach;
+	}
+
+	/* Add default transport to the tail */
+	if (strcmp(ft->name, FCOE_TRANSPORT_DEFAULT))
+		list_add(&ft->list, &fcoe_transports);
+	else
+		list_add_tail(&ft->list, &fcoe_transports);
+
+	ft->attached = true;
+	LIBFCOE_TRANSPORT_DBG("attaching transport %s\n", ft->name);
+
+out_attach:
+	mutex_unlock(&ft_mutex);
+	return rc;
+}
+EXPORT_SYMBOL(fcoe_transport_attach);
+
+/**
+ * fcoe_transport_detach - Detaches an FCoE transport
+ * @ft: The fcoe transport to be attached
+ *
+ * Returns : 0 for success
+ */
+int fcoe_transport_detach(struct fcoe_transport *ft)
+{
+	int rc = 0;
+	struct fcoe_netdev_mapping *nm = NULL, *tmp;
+
+	mutex_lock(&ft_mutex);
+	if (!ft->attached) {
+		LIBFCOE_TRANSPORT_DBG("transport %s already detached\n",
+			ft->name);
+		rc = -ENODEV;
+		goto out_attach;
+	}
+
+	/* remove netdev mapping for this transport as it is going away */
+	mutex_lock(&fn_mutex);
+	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
+		if (nm->ft == ft) {
+			LIBFCOE_TRANSPORT_DBG("transport %s going away, "
+				"remove its netdev mapping for %s\n",
+				ft->name, nm->netdev->name);
+			list_del(&nm->list);
+			kfree(nm);
+		}
+	}
+	mutex_unlock(&fn_mutex);
+
+	list_del(&ft->list);
+	ft->attached = false;
+	LIBFCOE_TRANSPORT_DBG("detaching transport %s\n", ft->name);
+
+out_attach:
+	mutex_unlock(&ft_mutex);
+	return rc;
+
+}
+EXPORT_SYMBOL(fcoe_transport_detach);
+
+static int fcoe_transport_show(char *buffer, const struct kernel_param *kp)
+{
+	int i, j;
+	struct fcoe_transport *ft = NULL;
+
+	i = j = sprintf(buffer, "Attached FCoE transports:");
+	mutex_lock(&ft_mutex);
+	list_for_each_entry(ft, &fcoe_transports, list) {
+		if (i >= PAGE_SIZE - IFNAMSIZ)
+			break;
+		i += snprintf(&buffer[i], IFNAMSIZ, "%s ", ft->name);
+	}
+	mutex_unlock(&ft_mutex);
+	if (i == j)
+		i += snprintf(&buffer[i], IFNAMSIZ, "none");
+	return i;
+}
+
+static int __init fcoe_transport_init(void)
+{
+	register_netdevice_notifier(&libfcoe_notifier);
+	return 0;
+}
+
+static int fcoe_transport_exit(void)
+{
+	struct fcoe_transport *ft;
+
+	unregister_netdevice_notifier(&libfcoe_notifier);
+	mutex_lock(&ft_mutex);
+	list_for_each_entry(ft, &fcoe_transports, list)
+		printk(KERN_ERR "FCoE transport %s is still attached!\n",
+		      ft->name);
+	mutex_unlock(&ft_mutex);
+	return 0;
+}
+
+
+static int fcoe_add_netdev_mapping(struct net_device *netdev,
+					struct fcoe_transport *ft)
+{
+	struct fcoe_netdev_mapping *nm;
+
+	nm = kmalloc(sizeof(*nm), GFP_KERNEL);
+	if (!nm) {
+		printk(KERN_ERR "Unable to allocate netdev_mapping");
+		return -ENOMEM;
+	}
+
+	nm->netdev = netdev;
+	nm->ft = ft;
+
+	mutex_lock(&fn_mutex);
+	list_add(&nm->list, &fcoe_netdevs);
+	mutex_unlock(&fn_mutex);
+	return 0;
+}
+
+
+static void fcoe_del_netdev_mapping(struct net_device *netdev)
+{
+	struct fcoe_netdev_mapping *nm = NULL, *tmp;
+
+	mutex_lock(&fn_mutex);
+	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
+		if (nm->netdev == netdev) {
+			list_del(&nm->list);
+			kfree(nm);
+			mutex_unlock(&fn_mutex);
+			return;
+		}
+	}
+	mutex_unlock(&fn_mutex);
+}
+
+
+/**
+ * fcoe_netdev_map_lookup - find the fcoe transport that matches the netdev on which
+ * it was created
+ * @netdev: The net device that the FCoE interface is on
+ *
+ * Returns : ptr to the fcoe transport that supports this netdev or NULL
+ * if not found.
+ *
+ * The ft_mutex should be held when this is called
+ */
+static struct fcoe_transport *fcoe_netdev_map_lookup(struct net_device *netdev)
+{
+	struct fcoe_transport *ft = NULL;
+	struct fcoe_netdev_mapping *nm;
+
+	mutex_lock(&fn_mutex);
+	list_for_each_entry(nm, &fcoe_netdevs, list) {
+		if (netdev == nm->netdev) {
+			ft = nm->ft;
+			mutex_unlock(&fn_mutex);
+			return ft;
+		}
+	}
+
+	mutex_unlock(&fn_mutex);
+	return NULL;
+}
+
+/**
+ * fcoe_if_to_netdev() - Parse a name buffer to get a net device
+ * @buffer: The name of the net device
+ *
+ * Returns: NULL or a ptr to net_device
+ */
+static struct net_device *fcoe_if_to_netdev(const char *buffer)
+{
+	char *cp;
+	char ifname[IFNAMSIZ + 2];
+
+	if (buffer) {
+		strlcpy(ifname, buffer, IFNAMSIZ);
+		cp = ifname + strlen(ifname);
+		while (--cp >= ifname && *cp == '\n')
+			*cp = '\0';
+		return dev_get_by_name(&init_net, ifname);
+	}
+	return NULL;
+}
+
+/**
+ * libfcoe_device_notification() - Handler for net device events
+ * @notifier: The context of the notification
+ * @event:    The type of event
+ * @ptr:      The net device that the event was on
+ *
+ * This function is called by the Ethernet driver in case of link change event.
+ *
+ * Returns: 0 for success
+ */
+static int libfcoe_device_notification(struct notifier_block *notifier,
+				    ulong event, void *ptr)
+{
+	struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
+
+	switch (event) {
+	case NETDEV_UNREGISTER:
+		LIBFCOE_TRANSPORT_DBG("NETDEV_UNREGISTER %s\n",
+				      netdev->name);
+		fcoe_del_netdev_mapping(netdev);
+		break;
+	}
+	return NOTIFY_OK;
+}
+
+ssize_t fcoe_ctlr_create_store(struct bus_type *bus,
+			       const char *buf, size_t count)
+{
+	struct net_device *netdev = NULL;
+	struct fcoe_transport *ft = NULL;
+	int rc = 0;
+	int err;
+
+	mutex_lock(&ft_mutex);
+
+	netdev = fcoe_if_to_netdev(buf);
+	if (!netdev) {
+		LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buf);
+		rc = -ENODEV;
+		goto out_nodev;
+	}
+
+	ft = fcoe_netdev_map_lookup(netdev);
+	if (ft) {
+		LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
+				      "FCoE instance on %s.\n",
+				      ft->name, netdev->name);
+		rc = -EEXIST;
+		goto out_putdev;
+	}
+
+	ft = fcoe_transport_lookup(netdev);
+	if (!ft) {
+		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
+				      netdev->name);
+		rc = -ENODEV;
+		goto out_putdev;
+	}
+
+	/* pass to transport create */
+	err = ft->alloc ? ft->alloc(netdev) : -ENODEV;
+	if (err) {
+		fcoe_del_netdev_mapping(netdev);
+		rc = -ENOMEM;
+		goto out_putdev;
+	}
+
+	err = fcoe_add_netdev_mapping(netdev, ft);
+	if (err) {
+		LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
+				      "for FCoE transport %s for %s.\n",
+				      ft->name, netdev->name);
+		rc = -ENODEV;
+		goto out_putdev;
+	}
+
+	LIBFCOE_TRANSPORT_DBG("transport %s succeeded to create fcoe on %s.\n",
+			      ft->name, netdev->name);
+
+out_putdev:
+	dev_put(netdev);
+out_nodev:
+	mutex_unlock(&ft_mutex);
+	if (rc)
+		return rc;
+	return count;
+}
+
+ssize_t fcoe_ctlr_destroy_store(struct bus_type *bus,
+				const char *buf, size_t count)
+{
+	int rc = -ENODEV;
+	struct net_device *netdev = NULL;
+	struct fcoe_transport *ft = NULL;
+
+	mutex_lock(&ft_mutex);
+
+	netdev = fcoe_if_to_netdev(buf);
+	if (!netdev) {
+		LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buf);
+		goto out_nodev;
+	}
+
+	ft = fcoe_netdev_map_lookup(netdev);
+	if (!ft) {
+		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
+				      netdev->name);
+		goto out_putdev;
+	}
+
+	/* pass to transport destroy */
+	rc = ft->destroy(netdev);
+	if (rc)
+		goto out_putdev;
+
+	fcoe_del_netdev_mapping(netdev);
+	LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
+			      ft->name, (rc) ? "failed" : "succeeded",
+			      netdev->name);
+	rc = count; /* required for successful return */
+out_putdev:
+	dev_put(netdev);
+out_nodev:
+	mutex_unlock(&ft_mutex);
+	return rc;
+}
+
+/**
+ * fcoe_transport_create() - Create a fcoe interface
+ * @buffer: The name of the Ethernet interface to create on
+ * @kp:	    The associated kernel param
+ *
+ * Called from sysfs. This holds the ft_mutex while calling the
+ * registered fcoe transport's create function.
+ *
+ * Returns: 0 for success
+ */
+static int fcoe_transport_create(const char *buffer,
+				 const struct kernel_param *kp)
+{
+	int rc = -ENODEV;
+	struct net_device *netdev = NULL;
+	struct fcoe_transport *ft = NULL;
+	enum fip_mode fip_mode = (enum fip_mode)(uintptr_t)kp->arg;
+
+	mutex_lock(&ft_mutex);
+
+	netdev = fcoe_if_to_netdev(buffer);
+	if (!netdev) {
+		LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buffer);
+		goto out_nodev;
+	}
+
+	ft = fcoe_netdev_map_lookup(netdev);
+	if (ft) {
+		LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
+				      "FCoE instance on %s.\n",
+				      ft->name, netdev->name);
+		rc = -EEXIST;
+		goto out_putdev;
+	}
+
+	ft = fcoe_transport_lookup(netdev);
+	if (!ft) {
+		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
+				      netdev->name);
+		goto out_putdev;
+	}
+
+	rc = fcoe_add_netdev_mapping(netdev, ft);
+	if (rc) {
+		LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
+				      "for FCoE transport %s for %s.\n",
+				      ft->name, netdev->name);
+		goto out_putdev;
+	}
+
+	/* pass to transport create */
+	rc = ft->create ? ft->create(netdev, fip_mode) : -ENODEV;
+	if (rc)
+		fcoe_del_netdev_mapping(netdev);
+
+	LIBFCOE_TRANSPORT_DBG("transport %s %s to create fcoe on %s.\n",
+			      ft->name, (rc) ? "failed" : "succeeded",
+			      netdev->name);
+
+out_putdev:
+	dev_put(netdev);
+out_nodev:
+	mutex_unlock(&ft_mutex);
+	return rc;
+}
+
+/**
+ * fcoe_transport_destroy() - Destroy a FCoE interface
+ * @buffer: The name of the Ethernet interface to be destroyed
+ * @kp:	    The associated kernel parameter
+ *
+ * Called from sysfs. This holds the ft_mutex while calling the
+ * registered fcoe transport's destroy function.
+ *
+ * Returns: 0 for success
+ */
+static int fcoe_transport_destroy(const char *buffer,
+				  const struct kernel_param *kp)
+{
+	int rc = -ENODEV;
+	struct net_device *netdev = NULL;
+	struct fcoe_transport *ft = NULL;
+
+	mutex_lock(&ft_mutex);
+
+	netdev = fcoe_if_to_netdev(buffer);
+	if (!netdev) {
+		LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buffer);
+		goto out_nodev;
+	}
+
+	ft = fcoe_netdev_map_lookup(netdev);
+	if (!ft) {
+		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
+				      netdev->name);
+		goto out_putdev;
+	}
+
+	/* pass to transport destroy */
+	rc = ft->destroy ? ft->destroy(netdev) : -ENODEV;
+	fcoe_del_netdev_mapping(netdev);
+	LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
+			      ft->name, (rc) ? "failed" : "succeeded",
+			      netdev->name);
+
+out_putdev:
+	dev_put(netdev);
+out_nodev:
+	mutex_unlock(&ft_mutex);
+	return rc;
+}
+
+/**
+ * fcoe_transport_disable() - Disables a FCoE interface
+ * @buffer: The name of the Ethernet interface to be disabled
+ * @kp:	    The associated kernel parameter
+ *
+ * Called from sysfs.
+ *
+ * Returns: 0 for success
+ */
+static int fcoe_transport_disable(const char *buffer,
+				  const struct kernel_param *kp)
+{
+	int rc = -ENODEV;
+	struct net_device *netdev = NULL;
+	struct fcoe_transport *ft = NULL;
+
+	mutex_lock(&ft_mutex);
+
+	netdev = fcoe_if_to_netdev(buffer);
+	if (!netdev)
+		goto out_nodev;
+
+	ft = fcoe_netdev_map_lookup(netdev);
+	if (!ft)
+		goto out_putdev;
+
+	rc = ft->disable ? ft->disable(netdev) : -ENODEV;
+
+out_putdev:
+	dev_put(netdev);
+out_nodev:
+	mutex_unlock(&ft_mutex);
+	return rc;
+}
+
+/**
+ * fcoe_transport_enable() - Enables a FCoE interface
+ * @buffer: The name of the Ethernet interface to be enabled
+ * @kp:     The associated kernel parameter
+ *
+ * Called from sysfs.
+ *
+ * Returns: 0 for success
+ */
+static int fcoe_transport_enable(const char *buffer,
+				 const struct kernel_param *kp)
+{
+	int rc = -ENODEV;
+	struct net_device *netdev = NULL;
+	struct fcoe_transport *ft = NULL;
+
+	mutex_lock(&ft_mutex);
+
+	netdev = fcoe_if_to_netdev(buffer);
+	if (!netdev)
+		goto out_nodev;
+
+	ft = fcoe_netdev_map_lookup(netdev);
+	if (!ft)
+		goto out_putdev;
+
+	rc = ft->enable ? ft->enable(netdev) : -ENODEV;
+
+out_putdev:
+	dev_put(netdev);
+out_nodev:
+	mutex_unlock(&ft_mutex);
+	return rc;
+}
+
+/**
+ * libfcoe_init() - Initialization routine for libfcoe.ko
+ */
+static int __init libfcoe_init(void)
+{
+	int rc = 0;
+
+	rc = fcoe_transport_init();
+	if (rc)
+		return rc;
+
+	rc = fcoe_sysfs_setup();
+	if (rc)
+		fcoe_transport_exit();
+
+	return rc;
+}
+module_init(libfcoe_init);
+
+/**
+ * libfcoe_exit() - Tear down libfcoe.ko
+ */
+static void __exit libfcoe_exit(void)
+{
+	fcoe_sysfs_teardown();
+	fcoe_transport_exit();
+}
+module_exit(libfcoe_exit);