[SCSI] libfcoe: Move common code from fcoe to libfcoe module

To facilitate LLDDs to reuse the code, skb queue related functions are moved to
libfcoe, so that both fcoe and bnx2fc drivers can use them. The common structures
fcoe_port, fcoe_percpu_s are moved to libfcoe. fcoe_port will now have an
opaque pointer that points to corresponding driver's interface structure.
Also, fcoe_start_io and fcoe_fc_crc are moved to libfcoe.

As part of this change, fixed fcoe_start_io to return ENOMEM if
skb_clone fails.

Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 21 insertions, 196 deletions

diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 46c57e5755a..495456fe452 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -75,7 +75,6 @@ static int fcoe_xmit(struct fc_lport *, struct fc_frame *);
 static int fcoe_rcv(struct sk_buff *, struct net_device *,
 		    struct packet_type *, struct net_device *);
 static int fcoe_percpu_receive_thread(void *);
-static void fcoe_clean_pending_queue(struct fc_lport *);
 static void fcoe_percpu_clean(struct fc_lport *);
 static int fcoe_link_speed_update(struct fc_lport *);
 static int fcoe_link_ok(struct fc_lport *);
@@ -83,7 +82,6 @@ static int fcoe_link_ok(struct fc_lport *);
 static struct fc_lport *fcoe_hostlist_lookup(const struct net_device *);
 static int fcoe_hostlist_add(const struct fc_lport *);
 
-static void fcoe_check_wait_queue(struct fc_lport *, struct sk_buff *);
 static int fcoe_device_notification(struct notifier_block *, ulong, void *);
 static void fcoe_dev_setup(void);
 static void fcoe_dev_cleanup(void);
@@ -506,7 +504,7 @@ static void fcoe_fip_send(struct fcoe_ctlr *fip, struct sk_buff *skb)
 static void fcoe_update_src_mac(struct fc_lport *lport, u8 *addr)
 {
 	struct fcoe_port *port = lport_priv(lport);
-	struct fcoe_interface *fcoe = port->fcoe;
+	struct fcoe_interface *fcoe = port->priv;
 
 	rtnl_lock();
 	if (!is_zero_ether_addr(port->data_src_addr))
@@ -562,17 +560,6 @@ static int fcoe_lport_config(struct fc_lport *lport)
 }
 
 /**
- * fcoe_queue_timer() - The fcoe queue timer
- * @lport: The local port
- *
- * Calls fcoe_check_wait_queue on timeout
- */
-static void fcoe_queue_timer(ulong lport)
-{
-	fcoe_check_wait_queue((struct fc_lport *)lport, NULL);
-}
-
-/**
  * fcoe_get_wwn() - Get the world wide name from LLD if it supports it
  * @netdev: the associated net device
  * @wwn: the output WWN
@@ -651,7 +638,7 @@ static int fcoe_netdev_config(struct fc_lport *lport, struct net_device *netdev)
 
 	/* Setup lport private data to point to fcoe softc */
 	port = lport_priv(lport);
-	fcoe = port->fcoe;
+	fcoe = port->priv;
 
 	/*
 	 * Determine max frame size based on underlying device and optional
@@ -761,7 +748,7 @@ bool fcoe_oem_match(struct fc_frame *fp)
 static inline int fcoe_em_config(struct fc_lport *lport)
 {
 	struct fcoe_port *port = lport_priv(lport);
-	struct fcoe_interface *fcoe = port->fcoe;
+	struct fcoe_interface *fcoe = port->priv;
 	struct fcoe_interface *oldfcoe = NULL;
 	struct net_device *old_real_dev, *cur_real_dev;
 	u16 min_xid = FCOE_MIN_XID;
@@ -845,7 +832,7 @@ skip_oem:
 static void fcoe_if_destroy(struct fc_lport *lport)
 {
 	struct fcoe_port *port = lport_priv(lport);
-	struct fcoe_interface *fcoe = port->fcoe;
+	struct fcoe_interface *fcoe = port->priv;
 	struct net_device *netdev = fcoe->netdev;
 
 	FCOE_NETDEV_DBG(netdev, "Destroying interface\n");
@@ -966,7 +953,9 @@ static struct fc_lport *fcoe_if_create(struct fcoe_interface *fcoe,
 	}
 	port = lport_priv(lport);
 	port->lport = lport;
-	port->fcoe = fcoe;
+	port->priv = fcoe;
+	port->max_queue_depth = FCOE_MAX_QUEUE_DEPTH;
+	port->min_queue_depth = FCOE_MIN_QUEUE_DEPTH;
 	INIT_WORK(&port->destroy_work, fcoe_destroy_work);
 
 	/* configure a fc_lport including the exchange manager */
@@ -1362,108 +1351,22 @@ err2:
 }
 
 /**
- * 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
- */
-static inline int fcoe_start_io(struct sk_buff *skb)
-{
-	struct sk_buff *nskb;
-	int rc;
-
-	nskb = skb_clone(skb, GFP_ATOMIC);
-	rc = dev_queue_xmit(nskb);
-	if (rc != 0)
-		return rc;
-	kfree_skb(skb);
-	return 0;
-}
-
-/**
- * fcoe_get_paged_crc_eof() - Allocate a page to be used for the trailer CRC
+ * fcoe_alloc_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
  *
- * 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
  */
-static int fcoe_get_paged_crc_eof(struct sk_buff *skb, int tlen)
+static int fcoe_alloc_paged_crc_eof(struct sk_buff *skb, int tlen)
 {
 	struct fcoe_percpu_s *fps;
-	struct page *page;
+	int rc;
 
 	fps = &get_cpu_var(fcoe_percpu);
-	page = fps->crc_eof_page;
-	if (!page) {
-		page = alloc_page(GFP_ATOMIC);
-		if (!page) {
-			put_cpu_var(fcoe_percpu);
-			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);
-	}
+	rc = fcoe_get_paged_crc_eof(skb, tlen, fps);
 	put_cpu_var(fcoe_percpu);
-	return 0;
-}
 
-/**
- * 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);
-	struct skb_frag_struct *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 = frag->page_offset;
-		len = frag->size;
-		while (len > 0) {
-			clen = min(len, PAGE_SIZE - (off & ~PAGE_MASK));
-			data = kmap_atomic(frag->page + (off >> PAGE_SHIFT),
-					   KM_SKB_DATA_SOFTIRQ);
-			crc = crc32(crc, data + (off & ~PAGE_MASK), clen);
-			kunmap_atomic(data, KM_SKB_DATA_SOFTIRQ);
-			off += clen;
-			len -= clen;
-		}
-	}
-	return crc;
+	return rc;
 }
 
 /**
@@ -1486,7 +1389,7 @@ int fcoe_xmit(struct fc_lport *lport, struct fc_frame *fp)
 	unsigned int tlen;		/* trailer length */
 	unsigned int elen;		/* eth header, may include vlan */
 	struct fcoe_port *port = lport_priv(lport);
-	struct fcoe_interface *fcoe = port->fcoe;
+	struct fcoe_interface *fcoe = port->priv;
 	u8 sof, eof;
 	struct fcoe_hdr *hp;
 
@@ -1527,7 +1430,7 @@ int fcoe_xmit(struct fc_lport *lport, struct fc_frame *fp)
 	/* copy port crc and eof to the skb buff */
 	if (skb_is_nonlinear(skb)) {
 		skb_frag_t *frag;
-		if (fcoe_get_paged_crc_eof(skb, tlen)) {
+		if (fcoe_alloc_paged_crc_eof(skb, tlen)) {
 			kfree_skb(skb);
 			return -ENOMEM;
 		}
@@ -1636,7 +1539,7 @@ static inline int fcoe_filter_frames(struct fc_lport *lport,
 	if (fh->fh_r_ctl == FC_RCTL_DD_SOL_DATA && fh->fh_type == FC_TYPE_FCP)
 		return 0;
 
-	fcoe = ((struct fcoe_port *)lport_priv(lport))->fcoe;
+	fcoe = ((struct fcoe_port *)lport_priv(lport))->priv;
 	if (is_fip_mode(&fcoe->ctlr) && fc_frame_payload_op(fp) == ELS_LOGO &&
 	    ntoh24(fh->fh_s_id) == FC_FID_FLOGI) {
 		FCOE_DBG("fcoe: dropping FCoE lport LOGO in fip mode\n");
@@ -1771,64 +1674,6 @@ int fcoe_percpu_receive_thread(void *arg)
 }
 
 /**
- * fcoe_check_wait_queue() - Attempt to clear the transmit backlog
- * @lport: The local port whose backlog is to be cleared
- *
- * 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.
- */
-static 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 < FCOE_LOW_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 > FCOE_MAX_QUEUE_DEPTH)
-		lport->qfull = 1;
-	spin_unlock_bh(&port->fcoe_pending_queue.lock);
-	return;
-}
-
-/**
  * fcoe_dev_setup() - Setup the link change notification interface
  */
 static void fcoe_dev_setup(void)
@@ -2180,8 +2025,7 @@ out_nodev:
  */
 int fcoe_link_speed_update(struct fc_lport *lport)
 {
-	struct fcoe_port *port = lport_priv(lport);
-	struct net_device *netdev = port->fcoe->netdev;
+	struct net_device *netdev = fcoe_netdev(lport);
 	struct ethtool_cmd ecmd = { ETHTOOL_GSET };
 
 	if (!dev_ethtool_get_settings(netdev, &ecmd)) {
@@ -2212,8 +2056,7 @@ int fcoe_link_speed_update(struct fc_lport *lport)
  */
 int fcoe_link_ok(struct fc_lport *lport)
 {
-	struct fcoe_port *port = lport_priv(lport);
-	struct net_device *netdev = port->fcoe->netdev;
+	struct net_device *netdev = fcoe_netdev(lport);
 
 	if (netif_oper_up(netdev))
 		return 0;
@@ -2277,24 +2120,6 @@ void fcoe_percpu_clean(struct fc_lport *lport)
 }
 
 /**
- * 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);
-}
-
-/**
  * fcoe_reset() - Reset a local port
  * @shost: The SCSI host associated with the local port to be reset
  *
@@ -2361,7 +2186,7 @@ static int fcoe_hostlist_add(const struct fc_lport *lport)
 	fcoe = fcoe_hostlist_lookup_port(fcoe_netdev(lport));
 	if (!fcoe) {
 		port = lport_priv(lport);
-		fcoe = port->fcoe;
+		fcoe = port->priv;
 		list_add_tail(&fcoe->list, &fcoe_hostlist);
 	}
 	return 0;
@@ -2555,7 +2380,7 @@ static struct fc_seq *fcoe_elsct_send(struct fc_lport *lport, u32 did,
 				      void *arg, u32 timeout)
 {
 	struct fcoe_port *port = lport_priv(lport);
-	struct fcoe_interface *fcoe = port->fcoe;
+	struct fcoe_interface *fcoe = port->priv;
 	struct fcoe_ctlr *fip = &fcoe->ctlr;
 	struct fc_frame_header *fh = fc_frame_header_get(fp);
 
@@ -2588,7 +2413,7 @@ static int fcoe_vport_create(struct fc_vport *vport, bool disabled)
 	struct Scsi_Host *shost = vport_to_shost(vport);
 	struct fc_lport *n_port = shost_priv(shost);
 	struct fcoe_port *port = lport_priv(n_port);
-	struct fcoe_interface *fcoe = port->fcoe;
+	struct fcoe_interface *fcoe = port->priv;
 	struct net_device *netdev = fcoe->netdev;
 	struct fc_lport *vn_port;
 
@@ -2732,7 +2557,7 @@ static void fcoe_set_port_id(struct fc_lport *lport,
 			     u32 port_id, struct fc_frame *fp)
 {
 	struct fcoe_port *port = lport_priv(lport);
-	struct fcoe_interface *fcoe = port->fcoe;
+	struct fcoe_interface *fcoe = port->priv;
 
 	if (fp && fc_frame_payload_op(fp) == ELS_FLOGI)
 		fcoe_ctlr_recv_flogi(&fcoe->ctlr, lport, fp);