[SCSI] fc_transport: add target driver support

This adds minimum target driver support like the srp transport does:

- fc_remote_port_{rolechg,delete} calls
scsi_tgt_it_nexus_{create,destroy} for target drivers.

- add callbacks to notify target drivers of the nexus and tmf
operation results to fc_function_template.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

4 files changed, 66 insertions, 0 deletions

diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 7877dfdd2322..e1efa0eac4ff 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -272,6 +272,13 @@ config SCSI_FC_ATTRS
           each attached FiberChannel device to sysfs, say Y.
           Otherwise, say N.
 
+config SCSI_FC_TGT_ATTRS
+        bool "SCSI target support for FiberChannel Transport Attributes"
+        depends on SCSI_FC_ATTRS
+        depends on SCSI_TGT = y || SCSI_TGT = SCSI_FC_ATTRS
+        help
+                If you want to use SCSI target mode drivers enable this option.
+
 config SCSI_ISCSI_ATTRS
         tristate "iSCSI Transport Attributes"
         depends on SCSI && NET
diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c
index dd97f2652508..8df0f080997f 100644
--- a/drivers/scsi/scsi_transport_fc.c
+++ b/drivers/scsi/scsi_transport_fc.c
@@ -36,6 +36,7 @@
 #include <net/netlink.h>
 #include <scsi/scsi_netlink_fc.h>
 #include "scsi_priv.h"
+#include "scsi_transport_fc_internal.h"
 
 static int fc_queue_work(struct Scsi_Host *, struct work_struct *);
 static void fc_vport_sched_delete(struct work_struct *work);
@@ -1956,6 +1957,19 @@ static int fc_user_scan(struct Scsi_Host *shost, uint channel,
         return 0;
 }
 
+static int fc_tsk_mgmt_response(struct Scsi_Host *shost, u64 nexus, u64 tm_id,
+                                int result)
+{
+        struct fc_internal *i = to_fc_internal(shost->transportt);
+        return i->f->tsk_mgmt_response(shost, nexus, tm_id, result);
+}
+
+static int fc_it_nexus_response(struct Scsi_Host *shost, u64 nexus, int result)
+{
+        struct fc_internal *i = to_fc_internal(shost->transportt);
+        return i->f->it_nexus_response(shost, nexus, result);
+}
+
 struct scsi_transport_template *
 fc_attach_transport(struct fc_function_template *ft)
 {
@@ -1999,6 +2013,10 @@ fc_attach_transport(struct fc_function_template *ft)
 
         i->t.user_scan = fc_user_scan;
 
+        /* target-mode drivers' functions */
+        i->t.tsk_mgmt_response = fc_tsk_mgmt_response;
+        i->t.it_nexus_response = fc_it_nexus_response;
+
         /*
          * Setup SCSI Target Attributes.
          */
@@ -2756,6 +2774,10 @@ fc_remote_port_delete(struct fc_rport  *rport)
 
         spin_unlock_irqrestore(shost->host_lock, flags);
 
+        if (rport->roles & FC_PORT_ROLE_FCP_INITIATOR &&
+            shost->active_mode & MODE_TARGET)
+                fc_tgt_it_nexus_destroy(shost, (unsigned long)rport);
+
         scsi_target_block(&rport->dev);
 
         /* see if we need to kill io faster than waiting for device loss */
@@ -2796,6 +2818,7 @@ fc_remote_port_rolechg(struct fc_rport  *rport, u32 roles)
         struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
         unsigned long flags;
         int create = 0;
+        int ret;
 
         spin_lock_irqsave(shost->host_lock, flags);
         if (roles & FC_PORT_ROLE_FCP_TARGET) {
@@ -2804,6 +2827,12 @@ fc_remote_port_rolechg(struct fc_rport  *rport, u32 roles)
                         create = 1;
                 } else if (!(rport->roles & FC_PORT_ROLE_FCP_TARGET))
                         create = 1;
+        } else if (shost->active_mode & MODE_TARGET) {
+                ret = fc_tgt_it_nexus_create(shost, (unsigned long)rport,
+                                             (char *)&rport->node_name);
+                if (ret)
+                        printk(KERN_ERR "FC Remore Port tgt nexus failed %d\n",
+                               ret);
         }
 
         rport->roles = roles;
diff --git a/drivers/scsi/scsi_transport_fc_internal.h b/drivers/scsi/scsi_transport_fc_internal.h
new file mode 100644
index 000000000000..e7bfbe751c1f
--- /dev/null
+++ b/drivers/scsi/scsi_transport_fc_internal.h
@@ -0,0 +1,26 @@
+#include <scsi/scsi_tgt.h>
+
+#ifdef CONFIG_SCSI_FC_TGT_ATTRS
+static inline int fc_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
+                                         char *initiator)
+{
+        return scsi_tgt_it_nexus_create(shost, itn_id, initiator);
+}
+
+static inline int fc_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
+{
+        return scsi_tgt_it_nexus_destroy(shost, itn_id);
+}
+#else
+static inline int fc_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
+                                         char *initiator)
+{
+        return 0;
+}
+
+static inline int fc_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
+{
+        return 0;
+}
+
+#endif
diff --git a/include/scsi/scsi_transport_fc.h b/include/scsi/scsi_transport_fc.h
index 616a96a3ab81..e466d886e192 100644
--- a/include/scsi/scsi_transport_fc.h
+++ b/include/scsi/scsi_transport_fc.h
@@ -589,6 +589,10 @@ struct fc_function_template {
         int     (*vport_disable)(struct fc_vport *, bool);
         int     (*vport_delete)(struct fc_vport *);
 
+        /* target-mode drivers' functions */
+        int     (* tsk_mgmt_response)(struct Scsi_Host *, u64, u64, int);
+        int     (* it_nexus_response)(struct Scsi_Host *, u64, int);
+
         /* allocation lengths for host-specific data */
         u32                             dd_fcrport_size;
         u32                             dd_fcvport_size;