target: Convert acl_node_lock to be IRQ-disabling

With qla2xxx, acl_node_lock is taken inside qla2xxx's hardware_lock,
which is taken in hardirq context.  This means acl_node_lock must become
an IRQ-disabling lock; in particular this fixes lockdep warnings along
the lines of

    ======================================================
    [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]

     (&(&se_tpg->acl_node_lock)->rlock){+.....}, at: [<ffffffffa026f872>] transport_deregister_session+0x92/0x140 [target_core_mod]

    and this task is already holding:
     (&(&ha->hardware_lock)->rlock){-.-...}, at: [<ffffffffa017c5e7>] qla_tgt_stop_phase1+0x57/0x2c0 [qla2xxx]
    which would create a new lock dependency:
     (&(&ha->hardware_lock)->rlock){-.-...} -> (&(&se_tpg->acl_node_lock)->rlock){+.....}

    but this new dependency connects a HARDIRQ-irq-safe lock:
     (&(&ha->hardware_lock)->rlock){-.-...}

    to a HARDIRQ-irq-unsafe lock:
     (&(&se_tpg->acl_node_lock)->rlock){+.....}

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/target/tcm_fc/tfc_conf.c b/drivers/target/tcm_fc/tfc_conf.c
index 520a8baae794..b15879d43e22 100644
--- a/drivers/target/tcm_fc/tfc_conf.c
+++ b/drivers/target/tcm_fc/tfc_conf.c
@@ -256,7 +256,7 @@ struct ft_node_acl *ft_acl_get(struct ft_tpg *tpg, struct fc_rport_priv *rdata)
         struct se_portal_group *se_tpg = &tpg->se_tpg;
         struct se_node_acl *se_acl;
 
-        spin_lock_bh(&se_tpg->acl_node_lock);
+        spin_lock_irq(&se_tpg->acl_node_lock);
         list_for_each_entry(se_acl, &se_tpg->acl_node_list, acl_list) {
                 acl = container_of(se_acl, struct ft_node_acl, se_node_acl);
                 pr_debug("acl %p port_name %llx\n",
@@ -270,7 +270,7 @@ struct ft_node_acl *ft_acl_get(struct ft_tpg *tpg, struct fc_rport_priv *rdata)
                         break;
                 }
         }
-        spin_unlock_bh(&se_tpg->acl_node_lock);
+        spin_unlock_irq(&se_tpg->acl_node_lock);
         return found;
 }