target: Make standard INQUIRY return 'not connected' for tpg_virt_lun0

This patch changes target_emulate_inquiry_std() to set the 'not connected'
(0x35) bit in standard INQUIRY response data when we are processing a
request to a virtual LUN=0 mapping from struct se_device *g_lun0_dev that
have been setup for us in transport_lookup_cmd_lun().

This addresses an issue where qla2xxx FC clients need to be able
to create demo-mode I_T FC Nexuses by default, but should not be
exposing the default set of TPG LUNs to all FC clients.  This includes
adding an new optional target_core_fabric_ops->tpg_check_demo_mode_login_only()
caller to allow demo_mode nexuses to skip the old default of bulding
a demo-mode MappedLUNs list via core_tpg_add_node_to_devs().

(roland: Add missing tpg_check_demo_mode_login_only check in core_dev_add_lun)

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>

diff --git a/drivers/target/target_core_cdb.c b/drivers/target/target_core_cdb.c
index 8ae09a1..d095408 100644 (file)
--- a/drivers/target/target_core_cdb.c
+++ b/drivers/target/target_core_cdb.c
@@ -67,6 +67,7 @@ target_emulate_inquiry_std(struct se_cmd *cmd)
 {
        struct se_lun *lun = cmd->se_lun;
        struct se_device *dev = cmd->se_dev;
+       struct se_portal_group *tpg = lun->lun_sep->sep_tpg;
        unsigned char *buf;
 
        /*
@@ -81,9 +82,13 @@ target_emulate_inquiry_std(struct se_cmd *cmd)
 
        buf = transport_kmap_first_data_page(cmd);
 
-       buf[0] = dev->transport->get_device_type(dev);
-       if (buf[0] == TYPE_TAPE)
-               buf[1] = 0x80;
+       if (dev == tpg->tpg_virt_lun0.lun_se_dev) {
+               buf[0] = 0x3f; /* Not connected */
+       } else {
+               buf[0] = dev->transport->get_device_type(dev);
+               if (buf[0] == TYPE_TAPE)
+                       buf[1] = 0x80;
+       }
        buf[2] = dev->transport->get_device_rev(dev);
 
        /*

diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index b38b6c9..ec3fbcd 100644 (file)
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -1346,7 +1346,9 @@ struct se_lun *core_dev_add_lun(
                struct se_node_acl *acl;
                spin_lock_bh(&tpg->acl_node_lock);
                list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
-                       if (acl->dynamic_node_acl) {
+                       if (acl->dynamic_node_acl &&
+                           (!tpg->se_tpg_tfo->tpg_check_demo_mode_login_only ||
+                            !tpg->se_tpg_tfo->tpg_check_demo_mode_login_only(tpg))) {
                                spin_unlock_bh(&tpg->acl_node_lock);
                                core_tpg_add_node_to_devs(acl, tpg);
                                spin_lock_bh(&tpg->acl_node_lock);

diff --git a/drivers/target/target_core_tpg.c b/drivers/target/target_core_tpg.c
index 4f1ba4c..718ccd1 100644 (file)
--- a/drivers/target/target_core_tpg.c
+++ b/drivers/target/target_core_tpg.c
@@ -298,8 +298,16 @@ struct se_node_acl *core_tpg_check_initiator_node_acl(
                tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
                return NULL;
        }
-
-       core_tpg_add_node_to_devs(acl, tpg);
+       /*
+        * Here we only create demo-mode MappedLUNs from the active
+        * TPG LUNs if the fabric is not explictly asking for
+        * tpg_check_demo_mode_login_only() == 1.
+        */
+       if ((tpg->se_tpg_tfo->tpg_check_demo_mode_login_only != NULL) &&
+           (tpg->se_tpg_tfo->tpg_check_demo_mode_login_only(tpg) == 1))
+               do { ; } while (0);
+       else
+               core_tpg_add_node_to_devs(acl, tpg);
 
        spin_lock_bh(&tpg->acl_node_lock);
        list_add_tail(&acl->acl_list, &tpg->acl_node_list);

diff --git a/include/target/target_core_fabric_ops.h b/include/target/target_core_fabric_ops.h
index 2de8fe9..126c675 100644 (file)
--- a/include/target/target_core_fabric_ops.h
+++ b/include/target/target_core_fabric_ops.h
@@ -27,6 +27,12 @@ struct target_core_fabric_ops {
        int (*tpg_check_demo_mode_cache)(struct se_portal_group *);
        int (*tpg_check_demo_mode_write_protect)(struct se_portal_group *);
        int (*tpg_check_prod_mode_write_protect)(struct se_portal_group *);
+       /*
+        * Optionally used by fabrics to allow demo-mode login, but not
+        * expose any TPG LUNs, and return 'not connected' in standard
+        * inquiry response
+        */
+       int (*tpg_check_demo_mode_login_only)(struct se_portal_group *);
        struct se_node_acl *(*tpg_alloc_fabric_acl)(
                                        struct se_portal_group *);
        void (*tpg_release_fabric_acl)(struct se_portal_group *,