Merge tag 'fcoe-3.13' into for-linus

Pull Request for 3.13 for FCOE tree.

Signed-off-by: James Bottomley <JBottomley@Parallels.com>

9 files changed, 294 insertions, 174 deletions

diff --git a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
index 3c204ad1d5b9..9b948505d118 100644
--- a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
@@ -542,8 +542,7 @@ static void bnx2fc_recv_frame(struct sk_buff *skb)
         vn_port = fc_vport_id_lookup(lport, ntoh24(fh->fh_d_id));
         if (vn_port) {
                 port = lport_priv(vn_port);
-                if (compare_ether_addr(port->data_src_addr, dest_mac)
-                    != 0) {
+                if (!ether_addr_equal(port->data_src_addr, dest_mac)) {
                         BNX2FC_HBA_DBG(lport, "fpma mismatch\n");
                         put_cpu();
                         kfree_skb(skb);
@@ -1381,6 +1380,7 @@ struct bnx2fc_interface *bnx2fc_interface_create(struct bnx2fc_hba *hba,
                 return NULL;
         }
         ctlr = fcoe_ctlr_device_priv(ctlr_dev);
+        ctlr->cdev = ctlr_dev;
         interface = fcoe_ctlr_priv(ctlr);
         dev_hold(netdev);
         kref_init(&interface->kref);
diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 07453bbf05e7..f3170008ae71 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -408,6 +408,7 @@ static struct fcoe_interface *fcoe_interface_create(struct net_device *netdev,
         }
 
         ctlr = fcoe_ctlr_device_priv(ctlr_dev);
+        ctlr->cdev = ctlr_dev;
         fcoe = fcoe_ctlr_priv(ctlr);
 
         dev_hold(netdev);
@@ -1440,22 +1441,28 @@ static int fcoe_rcv(struct sk_buff *skb, struct net_device *netdev,
         ctlr = fcoe_to_ctlr(fcoe);
         lport = ctlr->lp;
         if (unlikely(!lport)) {
-                FCOE_NETDEV_DBG(netdev, "Cannot find hba structure");
+                FCOE_NETDEV_DBG(netdev, "Cannot find hba structure\n");
                 goto err2;
         }
         if (!lport->link_up)
                 goto err2;
 
-        FCOE_NETDEV_DBG(netdev, "skb_info: len:%d data_len:%d head:%p "
-                        "data:%p tail:%p end:%p sum:%d dev:%s",
+        FCOE_NETDEV_DBG(netdev,
+                        "skb_info: len:%d data_len:%d head:%p data:%p tail:%p end:%p sum:%d dev:%s\n",
                         skb->len, skb->data_len, skb->head, skb->data,
                         skb_tail_pointer(skb), skb_end_pointer(skb),
                         skb->csum, skb->dev ? skb->dev->name : "<NULL>");
 
+
+        skb = skb_share_check(skb, GFP_ATOMIC);
+
+        if (skb == NULL)
+                return NET_RX_DROP;
+
         eh = eth_hdr(skb);
 
         if (is_fip_mode(ctlr) &&
-            compare_ether_addr(eh->h_source, ctlr->dest_addr)) {
+            !ether_addr_equal(eh->h_source, ctlr->dest_addr)) {
                 FCOE_NETDEV_DBG(netdev, "wrong source mac address:%pM\n",
                                 eh->h_source);
                 goto err;
@@ -1540,13 +1547,13 @@ static int fcoe_rcv(struct sk_buff *skb, struct net_device *netdev,
                 wake_up_process(fps->thread);
         spin_unlock(&fps->fcoe_rx_list.lock);
 
-        return 0;
+        return NET_RX_SUCCESS;
 err:
         per_cpu_ptr(lport->stats, get_cpu())->ErrorFrames++;
         put_cpu();
 err2:
         kfree_skb(skb);
-        return -1;
+        return NET_RX_DROP;
 }
 
 /**
@@ -1788,13 +1795,13 @@ static void fcoe_recv_frame(struct sk_buff *skb)
         lport = fr->fr_dev;
         if (unlikely(!lport)) {
                 if (skb->destructor != fcoe_percpu_flush_done)
-                        FCOE_NETDEV_DBG(skb->dev, "NULL lport in skb");
+                        FCOE_NETDEV_DBG(skb->dev, "NULL lport in skb\n");
                 kfree_skb(skb);
                 return;
         }
 
-        FCOE_NETDEV_DBG(skb->dev, "skb_info: len:%d data_len:%d "
-                        "head:%p data:%p tail:%p end:%p sum:%d dev:%s",
+        FCOE_NETDEV_DBG(skb->dev,
+                        "skb_info: len:%d data_len:%d head:%p data:%p tail:%p end:%p sum:%d dev:%s\n",
                         skb->len, skb->data_len,
                         skb->head, skb->data, skb_tail_pointer(skb),
                         skb_end_pointer(skb), skb->csum,
diff --git a/drivers/scsi/fcoe/fcoe_ctlr.c b/drivers/scsi/fcoe/fcoe_ctlr.c
index 203415e02518..34a1b1f333b4 100644
--- a/drivers/scsi/fcoe/fcoe_ctlr.c
+++ b/drivers/scsi/fcoe/fcoe_ctlr.c
@@ -160,74 +160,113 @@ void fcoe_ctlr_init(struct fcoe_ctlr *fip, enum fip_state mode)
 }
 EXPORT_SYMBOL(fcoe_ctlr_init);
 
+/**
+ * fcoe_sysfs_fcf_add() - Add a fcoe_fcf{,_device} to a fcoe_ctlr{,_device}
+ * @new: The newly discovered FCF
+ *
+ * Called with fip->ctlr_mutex held
+ */
 static int fcoe_sysfs_fcf_add(struct fcoe_fcf *new)
 {
         struct fcoe_ctlr *fip = new->fip;
-        struct fcoe_ctlr_device *ctlr_dev = fcoe_ctlr_to_ctlr_dev(fip);
-        struct fcoe_fcf_device temp, *fcf_dev;
-        int rc = 0;
+        struct fcoe_ctlr_device *ctlr_dev;
+        struct fcoe_fcf_device *temp, *fcf_dev;
+        int rc = -ENOMEM;
 
         LIBFCOE_FIP_DBG(fip, "New FCF fab %16.16llx mac %pM\n",
                         new->fabric_name, new->fcf_mac);
 
-        mutex_lock(&ctlr_dev->lock);
-
-        temp.fabric_name = new->fabric_name;
-        temp.switch_name = new->switch_name;
-        temp.fc_map = new->fc_map;
-        temp.vfid = new->vfid;
-        memcpy(temp.mac, new->fcf_mac, ETH_ALEN);
-        temp.priority = new->pri;
-        temp.fka_period = new->fka_period;
-        temp.selected = 0; /* default to unselected */
-
-        fcf_dev = fcoe_fcf_device_add(ctlr_dev, &temp);
-        if (unlikely(!fcf_dev)) {
-                rc = -ENOMEM;
+        temp = kzalloc(sizeof(*temp), GFP_KERNEL);
+        if (!temp)
                 goto out;
-        }
+
+        temp->fabric_name = new->fabric_name;
+        temp->switch_name = new->switch_name;
+        temp->fc_map = new->fc_map;
+        temp->vfid = new->vfid;
+        memcpy(temp->mac, new->fcf_mac, ETH_ALEN);
+        temp->priority = new->pri;
+        temp->fka_period = new->fka_period;
+        temp->selected = 0; /* default to unselected */
 
         /*
-         * The fcoe_sysfs layer can return a CONNECTED fcf that
-         * has a priv (fcf was never deleted) or a CONNECTED fcf
-         * that doesn't have a priv (fcf was deleted). However,
-         * libfcoe will always delete FCFs before trying to add
-         * them. This is ensured because both recv_adv and
-         * age_fcfs are protected by the the fcoe_ctlr's mutex.
-         * This means that we should never get a FCF with a
-         * non-NULL priv pointer.
+         * If ctlr_dev doesn't exist then it means we're a libfcoe user
+         * who doesn't use fcoe_syfs and didn't allocate a fcoe_ctlr_device.
+         * fnic would be an example of a driver with this behavior. In this
+         * case we want to add the fcoe_fcf to the fcoe_ctlr list, but we
+         * don't want to make sysfs changes.
          */
-        BUG_ON(fcf_dev->priv);
 
-        fcf_dev->priv = new;
-        new->fcf_dev = fcf_dev;
+        ctlr_dev = fcoe_ctlr_to_ctlr_dev(fip);
+        if (ctlr_dev) {
+                mutex_lock(&ctlr_dev->lock);
+                fcf_dev = fcoe_fcf_device_add(ctlr_dev, temp);
+                if (unlikely(!fcf_dev)) {
+                        rc = -ENOMEM;
+                        mutex_unlock(&ctlr_dev->lock);
+                        goto out;
+                }
+
+                /*
+                 * The fcoe_sysfs layer can return a CONNECTED fcf that
+                 * has a priv (fcf was never deleted) or a CONNECTED fcf
+                 * that doesn't have a priv (fcf was deleted). However,
+                 * libfcoe will always delete FCFs before trying to add
+                 * them. This is ensured because both recv_adv and
+                 * age_fcfs are protected by the the fcoe_ctlr's mutex.
+                 * This means that we should never get a FCF with a
+                 * non-NULL priv pointer.
+                 */
+                BUG_ON(fcf_dev->priv);
+
+                fcf_dev->priv = new;
+                new->fcf_dev = fcf_dev;
+                mutex_unlock(&ctlr_dev->lock);
+        }
 
         list_add(&new->list, &fip->fcfs);
         fip->fcf_count++;
+        rc = 0;
 
 out:
-        mutex_unlock(&ctlr_dev->lock);
+        kfree(temp);
         return rc;
 }
 
+/**
+ * fcoe_sysfs_fcf_del() - Remove a fcoe_fcf{,_device} to a fcoe_ctlr{,_device}
+ * @new: The FCF to be removed
+ *
+ * Called with fip->ctlr_mutex held
+ */
 static void fcoe_sysfs_fcf_del(struct fcoe_fcf *new)
 {
         struct fcoe_ctlr *fip = new->fip;
-        struct fcoe_ctlr_device *ctlr_dev = fcoe_ctlr_to_ctlr_dev(fip);
+        struct fcoe_ctlr_device *cdev;
         struct fcoe_fcf_device *fcf_dev;
 
         list_del(&new->list);
         fip->fcf_count--;
 
-        mutex_lock(&ctlr_dev->lock);
-
-        fcf_dev = fcoe_fcf_to_fcf_dev(new);
-        WARN_ON(!fcf_dev);
-        new->fcf_dev = NULL;
-        fcoe_fcf_device_delete(fcf_dev);
-        kfree(new);
-
-        mutex_unlock(&ctlr_dev->lock);
+        /*
+         * If ctlr_dev doesn't exist then it means we're a libfcoe user
+         * who doesn't use fcoe_syfs and didn't allocate a fcoe_ctlr_device
+         * or a fcoe_fcf_device.
+         *
+         * fnic would be an example of a driver with this behavior. In this
+         * case we want to remove the fcoe_fcf from the fcoe_ctlr list (above),
+         * but we don't want to make sysfs changes.
+         */
+        cdev = fcoe_ctlr_to_ctlr_dev(fip);
+        if (cdev) {
+                mutex_lock(&cdev->lock);
+                fcf_dev = fcoe_fcf_to_fcf_dev(new);
+                WARN_ON(!fcf_dev);
+                new->fcf_dev = NULL;
+                fcoe_fcf_device_delete(fcf_dev);
+                kfree(new);
+                mutex_unlock(&cdev->lock);
+        }
 }
 
 /**
@@ -300,7 +339,7 @@ static void fcoe_ctlr_announce(struct fcoe_ctlr *fip)
         spin_unlock_bh(&fip->ctlr_lock);
         sel = fip->sel_fcf;
 
-        if (sel && !compare_ether_addr(sel->fcf_mac, fip->dest_addr))
+        if (sel && ether_addr_equal(sel->fcf_mac, fip->dest_addr))
                 goto unlock;
         if (!is_zero_ether_addr(fip->dest_addr)) {
                 printk(KERN_NOTICE "libfcoe: host%d: "
@@ -1000,7 +1039,7 @@ static void fcoe_ctlr_recv_adv(struct fcoe_ctlr *fip, struct sk_buff *skb)
                 if (fcf->switch_name == new.switch_name &&
                     fcf->fabric_name == new.fabric_name &&
                     fcf->fc_map == new.fc_map &&
-                    compare_ether_addr(fcf->fcf_mac, new.fcf_mac) == 0) {
+                    ether_addr_equal(fcf->fcf_mac, new.fcf_mac)) {
                         found = 1;
                         break;
                 }
@@ -1340,7 +1379,7 @@ static void fcoe_ctlr_recv_clr_vlink(struct fcoe_ctlr *fip,
                         mp = (struct fip_mac_desc *)desc;
                         if (dlen < sizeof(*mp))
                                 goto err;
-                        if (compare_ether_addr(mp->fd_mac, fcf->fcf_mac))
+                        if (!ether_addr_equal(mp->fd_mac, fcf->fcf_mac))
                                 goto err;
                         desc_mask &= ~BIT(FIP_DT_MAC);
                         break;
@@ -1418,8 +1457,8 @@ static void fcoe_ctlr_recv_clr_vlink(struct fcoe_ctlr *fip,
                          * 'port_id' is already validated, check MAC address and
                          * wwpn
                          */
-                        if (compare_ether_addr(fip->get_src_addr(vn_port),
-                                                vp->fd_mac) != 0 ||
+                        if (!ether_addr_equal(fip->get_src_addr(vn_port),
+                                              vp->fd_mac) ||
                                 get_unaligned_be64(&vp->fd_wwpn) !=
                                                         vn_port->wwpn)
                                 continue;
@@ -1453,6 +1492,9 @@ err:
  */
 void fcoe_ctlr_recv(struct fcoe_ctlr *fip, struct sk_buff *skb)
 {
+        skb = skb_share_check(skb, GFP_ATOMIC);
+        if (!skb)
+                return;
         skb_queue_tail(&fip->fip_recv_list, skb);
         schedule_work(&fip->recv_work);
 }
@@ -1479,12 +1521,12 @@ static int fcoe_ctlr_recv_handler(struct fcoe_ctlr *fip, struct sk_buff *skb)
                 goto drop;
         eh = eth_hdr(skb);
         if (fip->mode == FIP_MODE_VN2VN) {
-                if (compare_ether_addr(eh->h_dest, fip->ctl_src_addr) &&
-                    compare_ether_addr(eh->h_dest, fcoe_all_vn2vn) &&
-                    compare_ether_addr(eh->h_dest, fcoe_all_p2p))
+                if (!ether_addr_equal(eh->h_dest, fip->ctl_src_addr) &&
+                    !ether_addr_equal(eh->h_dest, fcoe_all_vn2vn) &&
+                    !ether_addr_equal(eh->h_dest, fcoe_all_p2p))
                         goto drop;
-        } else if (compare_ether_addr(eh->h_dest, fip->ctl_src_addr) &&
-                   compare_ether_addr(eh->h_dest, fcoe_all_enode))
+        } else if (!ether_addr_equal(eh->h_dest, fip->ctl_src_addr) &&
+                   !ether_addr_equal(eh->h_dest, fcoe_all_enode))
                 goto drop;
         fiph = (struct fip_header *)skb->data;
         op = ntohs(fiph->fip_op);
@@ -1856,7 +1898,7 @@ int fcoe_ctlr_recv_flogi(struct fcoe_ctlr *fip, struct fc_lport *lport,
                  * address_mode flag to use FC_OUI-based Ethernet DA.
                  * Otherwise we use the FCoE gateway addr
                  */
-                if (!compare_ether_addr(sa, (u8[6])FC_FCOE_FLOGI_MAC)) {
+                if (ether_addr_equal(sa, (u8[6])FC_FCOE_FLOGI_MAC)) {
                         fcoe_ctlr_map_dest(fip);
                 } else {
                         memcpy(fip->dest_addr, sa, ETH_ALEN);
@@ -2825,8 +2867,8 @@ unlock:
  * disabled, so that should ensure that this routine is only called
  * when nothing is happening.
  */
-void fcoe_ctlr_mode_set(struct fc_lport *lport, struct fcoe_ctlr *fip,
-                        enum fip_state fip_mode)
+static void fcoe_ctlr_mode_set(struct fc_lport *lport, struct fcoe_ctlr *fip,
+                               enum fip_state fip_mode)
 {
         void *priv;
 
diff --git a/drivers/scsi/fcoe/fcoe_sysfs.c b/drivers/scsi/fcoe/fcoe_sysfs.c
index c9382d6eee78..d0d9a2d6120f 100644
--- a/drivers/scsi/fcoe/fcoe_sysfs.c
+++ b/drivers/scsi/fcoe/fcoe_sysfs.c
@@ -300,29 +300,29 @@ static ssize_t store_ctlr_mode(struct device *dev,
 
         switch (ctlr->enabled) {
         case FCOE_CTLR_ENABLED:
-                LIBFCOE_SYSFS_DBG(ctlr, "Cannot change mode when enabled.");
+                LIBFCOE_SYSFS_DBG(ctlr, "Cannot change mode when enabled.\n");
                 return -EBUSY;
         case FCOE_CTLR_DISABLED:
                 if (!ctlr->f->set_fcoe_ctlr_mode) {
                         LIBFCOE_SYSFS_DBG(ctlr,
-                                          "Mode change not supported by LLD.");
+                                          "Mode change not supported by LLD.\n");
                         return -ENOTSUPP;
                 }
 
                 ctlr->mode = fcoe_parse_mode(mode);
                 if (ctlr->mode == FIP_CONN_TYPE_UNKNOWN) {
-                        LIBFCOE_SYSFS_DBG(ctlr,
-                                          "Unknown mode %s provided.", buf);
+                        LIBFCOE_SYSFS_DBG(ctlr, "Unknown mode %s provided.\n",
+                                          buf);
                         return -EINVAL;
                 }
 
                 ctlr->f->set_fcoe_ctlr_mode(ctlr);
-                LIBFCOE_SYSFS_DBG(ctlr, "Mode changed to %s.", buf);
+                LIBFCOE_SYSFS_DBG(ctlr, "Mode changed to %s.\n", buf);
 
                 return count;
         case FCOE_CTLR_UNUSED:
         default:
-                LIBFCOE_SYSFS_DBG(ctlr, "Mode change not supported.");
+                LIBFCOE_SYSFS_DBG(ctlr, "Mode change not supported.\n");
                 return -ENOTSUPP;
         };
 }
@@ -653,7 +653,7 @@ static int fcoe_fcf_device_match(struct fcoe_fcf_device *new,
         if (new->switch_name == old->switch_name &&
             new->fabric_name == old->fabric_name &&
             new->fc_map == old->fc_map &&
-            compare_ether_addr(new->mac, old->mac) == 0)
+            ether_addr_equal(new->mac, old->mac))
                 return 1;
         return 0;
 }
diff --git a/drivers/scsi/fnic/fnic_fcs.c b/drivers/scsi/fnic/fnic_fcs.c
index 60a1c50aa68f..1671325aec7f 100644
--- a/drivers/scsi/fnic/fnic_fcs.c
+++ b/drivers/scsi/fnic/fnic_fcs.c
@@ -658,13 +658,13 @@ void fnic_update_mac_locked(struct fnic *fnic, u8 *new)
 
         if (is_zero_ether_addr(new))
                 new = ctl;
-        if (!compare_ether_addr(data, new))
+        if (ether_addr_equal(data, new))
                 return;
         FNIC_FCS_DBG(KERN_DEBUG, fnic->lport->host, "update_mac %pM\n", new);
-        if (!is_zero_ether_addr(data) && compare_ether_addr(data, ctl))
+        if (!is_zero_ether_addr(data) && !ether_addr_equal(data, ctl))
                 vnic_dev_del_addr(fnic->vdev, data);
         memcpy(data, new, ETH_ALEN);
-        if (compare_ether_addr(new, ctl))
+        if (!ether_addr_equal(new, ctl))
                 vnic_dev_add_addr(fnic->vdev, new);
 }
 
diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c
index 587992952b3c..1b3a09473452 100644
--- a/drivers/scsi/libfc/fc_exch.c
+++ b/drivers/scsi/libfc/fc_exch.c
@@ -27,6 +27,7 @@
 #include <linux/slab.h>
 #include <linux/err.h>
 #include <linux/export.h>
+#include <linux/log2.h>
 
 #include <scsi/fc/fc_fc2.h>
 
@@ -303,10 +304,7 @@ static void fc_exch_setup_hdr(struct fc_exch *ep, struct fc_frame *fp,
                 fr_eof(fp) = FC_EOF_N;
         }
 
-        /*
-         * Initialize remainig fh fields
-         * from fc_fill_fc_hdr
-         */
+        /* Initialize remaining fh fields from fc_fill_fc_hdr */
         fh->fh_ox_id = htons(ep->oxid);
         fh->fh_rx_id = htons(ep->rxid);
         fh->fh_seq_id = ep->seq.id;
@@ -362,9 +360,10 @@ static inline void fc_exch_timer_set_locked(struct fc_exch *ep,
 
         FC_EXCH_DBG(ep, "Exchange timer armed : %d msecs\n", timer_msec);
 
-        if (queue_delayed_work(fc_exch_workqueue, &ep->timeout_work,
-                               msecs_to_jiffies(timer_msec)))
-                fc_exch_hold(ep);               /* hold for timer */
+        fc_exch_hold(ep);               /* hold for timer */
+        if (!queue_delayed_work(fc_exch_workqueue, &ep->timeout_work,
+                                msecs_to_jiffies(timer_msec)))
+                fc_exch_release(ep);
 }
 
 /**
@@ -382,6 +381,8 @@ static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec)
 /**
  * fc_exch_done_locked() - Complete an exchange with the exchange lock held
  * @ep: The exchange that is complete
+ *
+ * Note: May sleep if invoked from outside a response handler.
  */
 static int fc_exch_done_locked(struct fc_exch *ep)
 {
@@ -393,7 +394,6 @@ static int fc_exch_done_locked(struct fc_exch *ep)
          * ep, and in that case we only clear the resp and set it as
          * complete, so it can be reused by the timer to send the rrq.
          */
-        ep->resp = NULL;
         if (ep->state & FC_EX_DONE)
                 return rc;
         ep->esb_stat |= ESB_ST_COMPLETE;
@@ -464,15 +464,21 @@ static void fc_exch_delete(struct fc_exch *ep)
 }
 
 static int fc_seq_send_locked(struct fc_lport *lport, struct fc_seq *sp,
-                       struct fc_frame *fp)
+                              struct fc_frame *fp)
 {
         struct fc_exch *ep;
         struct fc_frame_header *fh = fc_frame_header_get(fp);
-        int error;
+        int error = -ENXIO;
         u32 f_ctl;
         u8 fh_type = fh->fh_type;
 
         ep = fc_seq_exch(sp);
+
+        if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL)) {
+                fc_frame_free(fp);
+                goto out;
+        }
+
         WARN_ON(!(ep->esb_stat & ESB_ST_SEQ_INIT));
 
         f_ctl = ntoh24(fh->fh_f_ctl);
@@ -515,6 +521,9 @@ out:
  * @lport: The local port that the exchange will be sent on
  * @sp:    The sequence to be sent
  * @fp:    The frame to be sent on the exchange
+ *
+ * Note: The frame will be freed either by a direct call to fc_frame_free(fp)
+ * or indirectly by calling libfc_function_template.frame_send().
  */
 static int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp,
                        struct fc_frame *fp)
@@ -581,6 +590,8 @@ static struct fc_seq *fc_seq_start_next(struct fc_seq *sp)
 
 /*
  * Set the response handler for the exchange associated with a sequence.
+ *
+ * Note: May sleep if invoked from outside a response handler.
  */
 static void fc_seq_set_resp(struct fc_seq *sp,
                             void (*resp)(struct fc_seq *, struct fc_frame *,
@@ -588,8 +599,18 @@ static void fc_seq_set_resp(struct fc_seq *sp,
                             void *arg)
 {
         struct fc_exch *ep = fc_seq_exch(sp);
+        DEFINE_WAIT(wait);
 
         spin_lock_bh(&ep->ex_lock);
+        while (ep->resp_active && ep->resp_task != current) {
+                prepare_to_wait(&ep->resp_wq, &wait, TASK_UNINTERRUPTIBLE);
+                spin_unlock_bh(&ep->ex_lock);
+
+                schedule();
+
+                spin_lock_bh(&ep->ex_lock);
+        }
+        finish_wait(&ep->resp_wq, &wait);
         ep->resp = resp;
         ep->arg = arg;
         spin_unlock_bh(&ep->ex_lock);
@@ -622,27 +643,31 @@ static int fc_exch_abort_locked(struct fc_exch *ep,
         if (!sp)
                 return -ENOMEM;
 
-        ep->esb_stat |= ESB_ST_SEQ_INIT | ESB_ST_ABNORMAL;
         if (timer_msec)
                 fc_exch_timer_set_locked(ep, timer_msec);
 
-        /*
-         * If not logged into the fabric, don't send ABTS but leave
-         * sequence active until next timeout.
-         */
-        if (!ep->sid)
-                return 0;
-
-        /*
-         * Send an abort for the sequence that timed out.
-         */
-        fp = fc_frame_alloc(ep->lp, 0);
-        if (fp) {
-                fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid,
-                               FC_TYPE_BLS, FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
-                error = fc_seq_send_locked(ep->lp, sp, fp);
-        } else
-                error = -ENOBUFS;
+        if (ep->sid) {
+                /*
+                 * Send an abort for the sequence that timed out.
+                 */
+                fp = fc_frame_alloc(ep->lp, 0);
+                if (fp) {
+                        ep->esb_stat |= ESB_ST_SEQ_INIT;
+                        fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid,
+                                       FC_TYPE_BLS, FC_FC_END_SEQ |
+                                       FC_FC_SEQ_INIT, 0);
+                        error = fc_seq_send_locked(ep->lp, sp, fp);
+                } else {
+                        error = -ENOBUFS;
+                }
+        } else {
+                /*
+                 * If not logged into the fabric, don't send ABTS but leave
+                 * sequence active until next timeout.
+                 */
+                error = 0;
+        }
+        ep->esb_stat |= ESB_ST_ABNORMAL;
         return error;
 }
 
@@ -669,6 +694,61 @@ static int fc_seq_exch_abort(const struct fc_seq *req_sp,
 }
 
 /**
+ * fc_invoke_resp() - invoke ep->resp()
+ *
+ * Notes:
+ * It is assumed that after initialization finished (this means the
+ * first unlock of ex_lock after fc_exch_alloc()) ep->resp and ep->arg are
+ * modified only via fc_seq_set_resp(). This guarantees that none of these
+ * two variables changes if ep->resp_active > 0.
+ *
+ * If an fc_seq_set_resp() call is busy modifying ep->resp and ep->arg when
+ * this function is invoked, the first spin_lock_bh() call in this function
+ * will wait until fc_seq_set_resp() has finished modifying these variables.
+ *
+ * Since fc_exch_done() invokes fc_seq_set_resp() it is guaranteed that that
+ * ep->resp() won't be invoked after fc_exch_done() has returned.
+ *
+ * The response handler itself may invoke fc_exch_done(), which will clear the
+ * ep->resp pointer.
+ *
+ * Return value:
+ * Returns true if and only if ep->resp has been invoked.
+ */
+static bool fc_invoke_resp(struct fc_exch *ep, struct fc_seq *sp,
+                           struct fc_frame *fp)
+{
+        void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
+        void *arg;
+        bool res = false;
+
+        spin_lock_bh(&ep->ex_lock);
+        ep->resp_active++;
+        if (ep->resp_task != current)
+                ep->resp_task = !ep->resp_task ? current : NULL;
+        resp = ep->resp;
+        arg = ep->arg;
+        spin_unlock_bh(&ep->ex_lock);
+
+        if (resp) {
+                resp(sp, fp, arg);
+                res = true;
+        } else if (!IS_ERR(fp)) {
+                fc_frame_free(fp);
+        }
+
+        spin_lock_bh(&ep->ex_lock);
+        if (--ep->resp_active == 0)
+                ep->resp_task = NULL;
+        spin_unlock_bh(&ep->ex_lock);
+
+        if (ep->resp_active == 0)
+                wake_up(&ep->resp_wq);
+
+        return res;
+}
+
+/**
  * fc_exch_timeout() - Handle exchange timer expiration
  * @work: The work_struct identifying the exchange that timed out
  */
@@ -677,8 +757,6 @@ static void fc_exch_timeout(struct work_struct *work)
         struct fc_exch *ep = container_of(work, struct fc_exch,
                                           timeout_work.work);
         struct fc_seq *sp = &ep->seq;
-        void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
-        void *arg;
         u32 e_stat;
         int rc = 1;
 
@@ -696,16 +774,13 @@ static void fc_exch_timeout(struct work_struct *work)
                         fc_exch_rrq(ep);
                 goto done;
         } else {
-                resp = ep->resp;
-                arg = ep->arg;
-                ep->resp = NULL;
                 if (e_stat & ESB_ST_ABNORMAL)
                         rc = fc_exch_done_locked(ep);
                 spin_unlock_bh(&ep->ex_lock);
                 if (!rc)
                         fc_exch_delete(ep);
-                if (resp)
-                        resp(sp, ERR_PTR(-FC_EX_TIMEOUT), arg);
+                fc_invoke_resp(ep, sp, ERR_PTR(-FC_EX_TIMEOUT));
+                fc_seq_set_resp(sp, NULL, ep->arg);
                 fc_seq_exch_abort(sp, 2 * ep->r_a_tov);
                 goto done;
         }
@@ -792,6 +867,8 @@ hit:
         ep->f_ctl = FC_FC_FIRST_SEQ;    /* next seq is first seq */
         ep->rxid = FC_XID_UNKNOWN;
         ep->class = mp->class;
+        ep->resp_active = 0;
+        init_waitqueue_head(&ep->resp_wq);
         INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout);
 out:
         return ep;
@@ -838,8 +915,10 @@ static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid)
                 pool = per_cpu_ptr(mp->pool, xid & fc_cpu_mask);
                 spin_lock_bh(&pool->lock);
                 ep = fc_exch_ptr_get(pool, (xid - mp->min_xid) >> fc_cpu_order);
-                if (ep && ep->xid == xid)
+                if (ep) {
+                        WARN_ON(ep->xid != xid);
                         fc_exch_hold(ep);
+                }
                 spin_unlock_bh(&pool->lock);
         }
         return ep;
@@ -850,6 +929,8 @@ static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid)
  * fc_exch_done() - Indicate that an exchange/sequence tuple is complete and
  *                  the memory allocated for the related objects may be freed.
  * @sp: The sequence that has completed
+ *
+ * Note: May sleep if invoked from outside a response handler.
  */
 static void fc_exch_done(struct fc_seq *sp)
 {
@@ -859,6 +940,8 @@ static void fc_exch_done(struct fc_seq *sp)
         spin_lock_bh(&ep->ex_lock);
         rc = fc_exch_done_locked(ep);
         spin_unlock_bh(&ep->ex_lock);
+
+        fc_seq_set_resp(sp, NULL, ep->arg);
         if (!rc)
                 fc_exch_delete(ep);
 }
@@ -987,6 +1070,7 @@ static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport,
                 }
         }
 
+        spin_lock_bh(&ep->ex_lock);
         /*
          * At this point, we have the exchange held.
          * Find or create the sequence.
@@ -1014,11 +1098,11 @@ static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport,
                                  * sending RSP, hence write request on other
                                  * end never finishes.
                                  */
-                                spin_lock_bh(&ep->ex_lock);
                                 sp->ssb_stat |= SSB_ST_RESP;
                                 sp->id = fh->fh_seq_id;
-                                spin_unlock_bh(&ep->ex_lock);
                         } else {
+                                spin_unlock_bh(&ep->ex_lock);
+
                                 /* sequence/exch should exist */
                                 reject = FC_RJT_SEQ_ID;
                                 goto rel;
@@ -1029,6 +1113,7 @@ static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport,
 
         if (f_ctl & FC_FC_SEQ_INIT)
                 ep->esb_stat |= ESB_ST_SEQ_INIT;
+        spin_unlock_bh(&ep->ex_lock);
 
         fr_seq(fp) = sp;
 out:
@@ -1291,21 +1376,23 @@ static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp)
 
         if (!ep)
                 goto reject;
+
+        fp = fc_frame_alloc(ep->lp, sizeof(*ap));
+        if (!fp)
+                goto free;
+
         spin_lock_bh(&ep->ex_lock);
         if (ep->esb_stat & ESB_ST_COMPLETE) {
                 spin_unlock_bh(&ep->ex_lock);
+
+                fc_frame_free(fp);
                 goto reject;
         }
-        if (!(ep->esb_stat & ESB_ST_REC_QUAL))
+        if (!(ep->esb_stat & ESB_ST_REC_QUAL)) {
+                ep->esb_stat |= ESB_ST_REC_QUAL;
                 fc_exch_hold(ep);               /* hold for REC_QUAL */
-        ep->esb_stat |= ESB_ST_ABNORMAL | ESB_ST_REC_QUAL;
-        fc_exch_timer_set_locked(ep, ep->r_a_tov);
-
-        fp = fc_frame_alloc(ep->lp, sizeof(*ap));
-        if (!fp) {
-                spin_unlock_bh(&ep->ex_lock);
-                goto free;
         }
+        fc_exch_timer_set_locked(ep, ep->r_a_tov);
         fh = fc_frame_header_get(fp);
         ap = fc_frame_payload_get(fp, sizeof(*ap));
         memset(ap, 0, sizeof(*ap));
@@ -1319,14 +1406,16 @@ static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp)
         }
         sp = fc_seq_start_next_locked(sp);
         fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS);
+        ep->esb_stat |= ESB_ST_ABNORMAL;
         spin_unlock_bh(&ep->ex_lock);
+
+free:
         fc_frame_free(rx_fp);
         return;
 
 reject:
         fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID);
-free:
-        fc_frame_free(rx_fp);
+        goto free;
 }
 
 /**
@@ -1416,9 +1505,7 @@ static void fc_exch_recv_req(struct fc_lport *lport, struct fc_exch_mgr *mp,
                  * If new exch resp handler is valid then call that
                  * first.
                  */
-                if (ep->resp)
-                        ep->resp(sp, fp, ep->arg);
-                else
+                if (!fc_invoke_resp(ep, sp, fp))
                         lport->tt.lport_recv(lport, fp);
                 fc_exch_release(ep);    /* release from lookup */
         } else {
@@ -1442,8 +1529,6 @@ static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
         struct fc_exch *ep;
         enum fc_sof sof;
         u32 f_ctl;
-        void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
-        void *ex_resp_arg;
         int rc;
 
         ep = fc_exch_find(mp, ntohs(fh->fh_ox_id));
@@ -1478,19 +1563,19 @@ static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
 
         f_ctl = ntoh24(fh->fh_f_ctl);
         fr_seq(fp) = sp;
+
+        spin_lock_bh(&ep->ex_lock);
         if (f_ctl & FC_FC_SEQ_INIT)
                 ep->esb_stat |= ESB_ST_SEQ_INIT;
+        spin_unlock_bh(&ep->ex_lock);
 
         if (fc_sof_needs_ack(sof))
                 fc_seq_send_ack(sp, fp);
-        resp = ep->resp;
-        ex_resp_arg = ep->arg;
 
         if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T &&
             (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) ==
             (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) {
                 spin_lock_bh(&ep->ex_lock);
-                resp = ep->resp;
                 rc = fc_exch_done_locked(ep);
                 WARN_ON(fc_seq_exch(sp) != ep);
                 spin_unlock_bh(&ep->ex_lock);
@@ -1511,10 +1596,8 @@ static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
          * If new exch resp handler is valid then call that
          * first.
          */
-        if (resp)
-                resp(sp, fp, ex_resp_arg);
-        else
-                fc_frame_free(fp);
+        fc_invoke_resp(ep, sp, fp);
+
         fc_exch_release(ep);
         return;
 rel:
@@ -1553,8 +1636,6 @@ static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
  */
 static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp)
 {
-        void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
-        void *ex_resp_arg;
         struct fc_frame_header *fh;
         struct fc_ba_acc *ap;
         struct fc_seq *sp;
@@ -1599,9 +1680,6 @@ static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp)
                 break;
         }
 
-        resp = ep->resp;
-        ex_resp_arg = ep->arg;
-
         /* do we need to do some other checks here. Can we reuse more of
          * fc_exch_recv_seq_resp
          */
@@ -1613,17 +1691,14 @@ static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp)
             ntoh24(fh->fh_f_ctl) & FC_FC_LAST_SEQ)
                 rc = fc_exch_done_locked(ep);
         spin_unlock_bh(&ep->ex_lock);
+
+        fc_exch_hold(ep);
         if (!rc)
                 fc_exch_delete(ep);
-
-        if (resp)
-                resp(sp, fp, ex_resp_arg);
-        else
-                fc_frame_free(fp);
-
+        fc_invoke_resp(ep, sp, fp);
         if (has_rec)
                 fc_exch_timer_set(ep, ep->r_a_tov);
-
+        fc_exch_release(ep);
 }
 
 /**
@@ -1662,7 +1737,7 @@ static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp)
                         break;
                 default:
                         if (ep)
-                                FC_EXCH_DBG(ep, "BLS rctl %x - %s received",
+                                FC_EXCH_DBG(ep, "BLS rctl %x - %s received\n",
                                             fh->fh_r_ctl,
                                             fc_exch_rctl_name(fh->fh_r_ctl));
                         break;
@@ -1745,32 +1820,33 @@ static void fc_seq_ls_rjt(struct fc_frame *rx_fp, enum fc_els_rjt_reason reason,
 /**
  * fc_exch_reset() - Reset an exchange
  * @ep: The exchange to be reset
+ *
+ * Note: May sleep if invoked from outside a response handler.
  */
 static void fc_exch_reset(struct fc_exch *ep)
 {
         struct fc_seq *sp;
-        void (*resp)(struct fc_seq *, struct fc_frame *, void *);
-        void *arg;
         int rc = 1;
 
         spin_lock_bh(&ep->ex_lock);
         fc_exch_abort_locked(ep, 0);
         ep->state |= FC_EX_RST_CLEANUP;
         fc_exch_timer_cancel(ep);
-        resp = ep->resp;
-        ep->resp = NULL;
         if (ep->esb_stat & ESB_ST_REC_QUAL)
                 atomic_dec(&ep->ex_refcnt);     /* drop hold for rec_qual */
         ep->esb_stat &= ~ESB_ST_REC_QUAL;
-        arg = ep->arg;
         sp = &ep->seq;
         rc = fc_exch_done_locked(ep);
         spin_unlock_bh(&ep->ex_lock);
+
+        fc_exch_hold(ep);
+
         if (!rc)
                 fc_exch_delete(ep);
 
-        if (resp)
-                resp(sp, ERR_PTR(-FC_EX_CLOSED), arg);
+        fc_invoke_resp(ep, sp, ERR_PTR(-FC_EX_CLOSED));
+        fc_seq_set_resp(sp, NULL, ep->arg);
+        fc_exch_release(ep);
 }
 
 /**
@@ -1956,13 +2032,13 @@ static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg)
 
         switch (op) {
         case ELS_LS_RJT:
-                FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ");
+                FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ\n");
                 /* fall through */
         case ELS_LS_ACC:
                 goto cleanup;
         default:
-                FC_EXCH_DBG(aborted_ep, "unexpected response op %x "
-                            "for RRQ", op);
+                FC_EXCH_DBG(aborted_ep, "unexpected response op %x for RRQ\n",
+                            op);
                 return;
         }
 
@@ -2533,13 +2609,8 @@ int fc_setup_exch_mgr(void)
          * cpu on which exchange originated by simple bitwise
          * AND operation between fc_cpu_mask and exchange id.
          */
-        fc_cpu_mask = 1;
-        fc_cpu_order = 0;
-        while (fc_cpu_mask < nr_cpu_ids) {
-                fc_cpu_mask <<= 1;
-                fc_cpu_order++;
-        }
-        fc_cpu_mask--;
+        fc_cpu_order = ilog2(roundup_pow_of_two(nr_cpu_ids));
+        fc_cpu_mask = (1 << fc_cpu_order) - 1;
 
         fc_exch_workqueue = create_singlethread_workqueue("fc_exch_workqueue");
         if (!fc_exch_workqueue)
diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c
index 5fd0f1fbe586..1d7e76e8b447 100644
--- a/drivers/scsi/libfc/fc_fcp.c
+++ b/drivers/scsi/libfc/fc_fcp.c
@@ -902,7 +902,8 @@ static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
         /*
          * Check for missing or extra data frames.
          */
-        if (unlikely(fsp->xfer_len != expected_len)) {
+        if (unlikely(fsp->cdb_status == SAM_STAT_GOOD &&
+                     fsp->xfer_len != expected_len)) {
                 if (fsp->xfer_len < expected_len) {
                         /*
                          * Some data may be queued locally,
@@ -955,12 +956,11 @@ static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
                  * Test for transport underrun, independent of response
                  * underrun status.
                  */
-                if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
+                if (fsp->cdb_status == SAM_STAT_GOOD &&
+                    fsp->xfer_len < fsp->data_len && !fsp->io_status &&
                     (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
-                     fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
+                     fsp->xfer_len < fsp->data_len - fsp->scsi_resid))
                         fsp->status_code = FC_DATA_UNDRUN;
-                        fsp->io_status = 0;
-                }
         }
 
         seq = fsp->seq_ptr;
diff --git a/drivers/scsi/libfc/fc_lport.c b/drivers/scsi/libfc/fc_lport.c
index f04d15c67df3..e01a29863c38 100644
--- a/drivers/scsi/libfc/fc_lport.c
+++ b/drivers/scsi/libfc/fc_lport.c
@@ -516,7 +516,7 @@ static void fc_lport_recv_rnid_req(struct fc_lport *lport,
  * @lport: The local port receiving the LOGO
  * @fp:    The LOGO request frame
  *
- * Locking Note: The lport lock is exected to be held before calling
+ * Locking Note: The lport lock is expected to be held before calling
  * this function.
  */
 static void fc_lport_recv_logo_req(struct fc_lport *lport, struct fc_frame *fp)
@@ -1088,7 +1088,7 @@ static void fc_lport_error(struct fc_lport *lport, struct fc_frame *fp)
 {
         unsigned long delay = 0;
         FC_LPORT_DBG(lport, "Error %ld in state %s, retries %d\n",
-                     PTR_ERR(fp), fc_lport_state(lport),
+                     IS_ERR(fp) ? -PTR_ERR(fp) : 0, fc_lport_state(lport),
                      lport->retry_count);
 
         if (PTR_ERR(fp) == -FC_EX_CLOSED)
diff --git a/drivers/scsi/libfc/fc_rport.c b/drivers/scsi/libfc/fc_rport.c
index c710d908fda6..589ff9aedd31 100644
--- a/drivers/scsi/libfc/fc_rport.c
+++ b/drivers/scsi/libfc/fc_rport.c
@@ -1705,7 +1705,7 @@ reject:
  * @rdata: The remote port that sent the PRLI request
  * @rx_fp: The PRLI request frame
  *
- * Locking Note: The rport lock is exected to be held before calling
+ * Locking Note: The rport lock is expected to be held before calling
  * this function.
  */
 static void fc_rport_recv_prli_req(struct fc_rport_priv *rdata,
@@ -1824,7 +1824,7 @@ drop:
  * @rdata: The remote port that sent the PRLO request
  * @rx_fp: The PRLO request frame
  *
- * Locking Note: The rport lock is exected to be held before calling
+ * Locking Note: The rport lock is expected to be held before calling
  * this function.
  */
 static void fc_rport_recv_prlo_req(struct fc_rport_priv *rdata,
@@ -1895,7 +1895,7 @@ drop:
  * @lport: The local port that received the LOGO request
  * @fp:    The LOGO request frame
  *
- * Locking Note: The rport lock is exected to be held before calling
+ * Locking Note: The rport lock is expected to be held before calling
  * this function.
  */
 static void fc_rport_recv_logo_req(struct fc_lport *lport, struct fc_frame *fp)