[SCSI] tcm_qla2xxx: Add >= 24xx series fabric module for target-core

This patch adds support for tcm_qla2xxx fabric module for target-core
using the new qla_target.c LLD logic.  This includes support for explict
NodeACLs via configfs using tcm_qla2xxx_setup_nacl_from_rport() from libfc
struct fc_host->rports, and demo-mode support for virtual LUN=0 access.

This patch also adds support for using tcm_qla2xxx_lport->lport_fcport_map
and ->lport_loopid_map of btree_head32 to track struct se_node_acl pointers
for individual 24-bit Port ID and 16-bit Loop ID values w/ qla_target_template
->find_sess_by_s_id() and ->find_sess_by_loop_id() used in a number of
locations into the primary I/O dispatch logic in qla_target.c LLD code.

The main piece for FC Nexus setup is in tcm_qla2xxx_check_initiator_node_acl(),
which calls tcm_qla2xxx_set_sess_by_[s_id,loop_id]() to setup our
lport->lport_fcport_map and lport_loopid_map pointers respectively, and
register the new nexus with TCM via __transport_register_session().

(nab: Add qla_tgt_mgmt_cmd usage with TARGET_SCF_ACK_KREF during TMRs +
      change tcm_qla2xxx_nacl->nport_id to u32 (DanC))
(danc: tcm_qla2xxx: checking for NULL instead of IS_ERR())
(roland: Fix up v3.5 breakage for removal of transport_do_task_sg_chain +
         Add hook so qla_target code can shutdown sessions)
(steveh: Convert FC address map from flat array to btree)
(randy: fix qla2xxx printk format warnings for size_t)
(joern: Make most of tcm_qla2xxx static + remove unnecessary
        workqueue_struct prototypes + use WWN_SIZE instead of hard-coded
        constants)

Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/qla2xxx/Kconfig

@@ -25,3 +25,12 @@ config SCSI_QLA_FC
 	Firmware images can be retrieved from:
 
 		ftp://ftp.qlogic.com/outgoing/linux/firmware/
+
+config TCM_QLA2XXX
+	tristate "TCM_QLA2XXX fabric module for Qlogic 2xxx series target mode HBAs"
+	depends on SCSI_QLA_FC && TARGET_CORE
+	select LIBFC
+	select BTREE
+	default n
+	---help---
+	Say Y here to enable the TCM_QLA2XXX fabric module for Qlogic 2xxx series target mode HBAs

drivers/scsi/qla2xxx/Makefile

@@ -3,3 +3,4 @@ qla2xxx-y := qla_os.o qla_init.o qla_mbx.o qla_iocb.o qla_isr.o qla_gs.o \
         qla_nx.o qla_target.o
 
 obj-$(CONFIG_SCSI_QLA_FC) += qla2xxx.o
+obj-$(CONFIG_TCM_QLA2XXX) += tcm_qla2xxx.o