[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

drivers/scsi/qla2xxx/tcm_qla2xxx.h

@@ -0,0 +1,82 @@
+#include <target/target_core_base.h>
+#include <linux/btree.h>
+
+#define TCM_QLA2XXX_VERSION	"v0.1"
+/* length of ASCII WWPNs including pad */
+#define TCM_QLA2XXX_NAMELEN	32
+/* lenth of ASCII NPIV 'WWPN+WWNN' including pad */
+#define TCM_QLA2XXX_NPIV_NAMELEN 66
+
+#include "qla_target.h"
+
+struct tcm_qla2xxx_nacl {
+	/* From libfc struct fc_rport->port_id */
+	u32 nport_id;
+	/* Binary World Wide unique Node Name for remote FC Initiator Nport */
+	u64 nport_wwnn;
+	/* ASCII formatted WWPN for FC Initiator Nport */
+	char nport_name[TCM_QLA2XXX_NAMELEN];
+	/* Pointer to qla_tgt_sess */
+	struct qla_tgt_sess *qla_tgt_sess;
+	/* Pointer to TCM FC nexus */
+	struct se_session *nport_nexus;
+	/* Returned by tcm_qla2xxx_make_nodeacl() */
+	struct se_node_acl se_node_acl;
+};
+
+struct tcm_qla2xxx_tpg_attrib {
+	int generate_node_acls;
+	int cache_dynamic_acls;
+	int demo_mode_write_protect;
+	int prod_mode_write_protect;
+};
+
+struct tcm_qla2xxx_tpg {
+	/* FC lport target portal group tag for TCM */
+	u16 lport_tpgt;
+	/* Atomic bit to determine TPG active status */
+	atomic_t lport_tpg_enabled;
+	/* Pointer back to tcm_qla2xxx_lport */
+	struct tcm_qla2xxx_lport *lport;
+	/* Used by tcm_qla2xxx_tpg_attrib_cit */
+	struct tcm_qla2xxx_tpg_attrib tpg_attrib;
+	/* Returned by tcm_qla2xxx_make_tpg() */
+	struct se_portal_group se_tpg;
+};
+
+#define QLA_TPG_ATTRIB(tpg)	(&(tpg)->tpg_attrib)
+
+struct tcm_qla2xxx_fc_loopid {
+	struct se_node_acl *se_nacl;
+};
+
+struct tcm_qla2xxx_lport {
+	/* SCSI protocol the lport is providing */
+	u8 lport_proto_id;
+	/* Binary World Wide unique Port Name for FC Target Lport */
+	u64 lport_wwpn;
+	/* Binary World Wide unique Port Name for FC NPIV Target Lport */
+	u64 lport_npiv_wwpn;
+	/* Binary World Wide unique Node Name for FC NPIV Target Lport */
+	u64 lport_npiv_wwnn;
+	/* ASCII formatted WWPN for FC Target Lport */
+	char lport_name[TCM_QLA2XXX_NAMELEN];
+	/* ASCII formatted WWPN+WWNN for NPIV FC Target Lport */
+	char lport_npiv_name[TCM_QLA2XXX_NPIV_NAMELEN];
+	/* map for fc_port pointers in 24-bit FC Port ID space */
+	struct btree_head32 lport_fcport_map;
+	/* vmalloc-ed memory for fc_port pointers for 16-bit FC loop ID */
+	struct tcm_qla2xxx_fc_loopid *lport_loopid_map;
+	/* Pointer to struct scsi_qla_host from qla2xxx LLD */
+	struct scsi_qla_host *qla_vha;
+	/* Pointer to struct scsi_qla_host for NPIV VP from qla2xxx LLD */
+	struct scsi_qla_host *qla_npiv_vp;
+	/* Pointer to struct qla_tgt pointer */
+	struct qla_tgt lport_qla_tgt;
+	/* Pointer to struct fc_vport for NPIV vport from libfc */
+	struct fc_vport *npiv_vport;
+	/* Pointer to TPG=1 for non NPIV mode */
+	struct tcm_qla2xxx_tpg *tpg_1;
+	/* Returned by tcm_qla2xxx_make_lport() */
+	struct se_wwn lport_wwn;
+};