iscsi-target: Remove SCF_SE_LUN_CMD flag abuses

This patch removes a number of SCF_SE_LUN_CMD flag abuses within iscsi-target
code to determine when iscsit_release_cmd() or transport_generic_free_cmd()
should be called while releasing an individual iscsi_cmd descriptor.

In the place of SCF_SE_LUN_CMD checks, this patch converts existing code to
use a new iscsit_free_cmd() that inspects iscsi_cmd->iscsi_opcode types to
determine which of the above functions should be invoked.  It also removes the
now unnecessary special case checking in iscsit_release_commands_from_conn().

(hch: Use iscsit_free_cmd instead of open-coded alternative)

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

4 files changed, 28 insertions, 56 deletions

diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index e4b9ba296dcf..d86e18dc163a 100644
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -3538,16 +3538,8 @@ get_immediate:
                                 spin_lock_bh(&conn->cmd_lock);
                                 list_del(&cmd->i_list);
                                 spin_unlock_bh(&conn->cmd_lock);
-                                /*
-                                 * Determine if a struct se_cmd is assoicated with
-                                 * this struct iscsi_cmd.
-                                 */
-                                if (!(cmd->se_cmd.se_cmd_flags & SCF_SE_LUN_CMD) &&
-                                    !(cmd->tmr_req))
-                                        iscsit_release_cmd(cmd);
-                                else
-                                        transport_generic_free_cmd(&cmd->se_cmd,
-                                                                1);
+
+                                iscsit_free_cmd(cmd);
                                 goto get_immediate;
                         case ISTATE_SEND_NOPIN_WANT_RESPONSE:
                                 spin_unlock_bh(&cmd->istate_lock);
@@ -3947,30 +3939,13 @@ static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
          */
         spin_lock_bh(&conn->cmd_lock);
         list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_list) {
-                if (!(cmd->se_cmd.se_cmd_flags & SCF_SE_LUN_CMD)) {
-
-                        list_del(&cmd->i_list);
-                        spin_unlock_bh(&conn->cmd_lock);
-                        iscsit_increment_maxcmdsn(cmd, sess);
-                        /*
-                         * Special cases for active iSCSI TMR, and
-                         * transport_lookup_cmd_lun() failing from
-                         * iscsit_get_lun_for_cmd() in iscsit_handle_scsi_cmd().
-                         */
-                        if (cmd->tmr_req)
-                                transport_generic_free_cmd(&cmd->se_cmd, 1);
-                        else
-                                iscsit_release_cmd(cmd);
 
-                        spin_lock_bh(&conn->cmd_lock);
-                        continue;
-                }
                 list_del(&cmd->i_list);
                 spin_unlock_bh(&conn->cmd_lock);
 
                 iscsit_increment_maxcmdsn(cmd, sess);
 
-                transport_generic_free_cmd(&cmd->se_cmd, 1);
+                iscsit_free_cmd(cmd);
 
                 spin_lock_bh(&conn->cmd_lock);
         }
diff --git a/drivers/target/iscsi/iscsi_target_erl2.c b/drivers/target/iscsi/iscsi_target_erl2.c
index c3803b2fdd65..0b8404c30125 100644
--- a/drivers/target/iscsi/iscsi_target_erl2.c
+++ b/drivers/target/iscsi/iscsi_target_erl2.c
@@ -143,10 +143,7 @@ void iscsit_free_connection_recovery_entires(struct iscsi_session *sess)
                         list_del(&cmd->i_list);
                         cmd->conn = NULL;
                         spin_unlock(&cr->conn_recovery_cmd_lock);
-                        if (!(cmd->se_cmd.se_cmd_flags & SCF_SE_LUN_CMD))
-                                iscsit_release_cmd(cmd);
-                        else
-                                transport_generic_free_cmd(&cmd->se_cmd, 1);
+                        iscsit_free_cmd(cmd);
                         spin_lock(&cr->conn_recovery_cmd_lock);
                 }
                 spin_unlock(&cr->conn_recovery_cmd_lock);
@@ -168,10 +165,7 @@ void iscsit_free_connection_recovery_entires(struct iscsi_session *sess)
                         list_del(&cmd->i_list);
                         cmd->conn = NULL;
                         spin_unlock(&cr->conn_recovery_cmd_lock);
-                        if (!(cmd->se_cmd.se_cmd_flags & SCF_SE_LUN_CMD))
-                                iscsit_release_cmd(cmd);
-                        else
-                                transport_generic_free_cmd(&cmd->se_cmd, 1);
+                        iscsit_free_cmd(cmd);
                         spin_lock(&cr->conn_recovery_cmd_lock);
                 }
                 spin_unlock(&cr->conn_recovery_cmd_lock);
@@ -256,10 +250,7 @@ void iscsit_discard_cr_cmds_by_expstatsn(
                 iscsit_remove_cmd_from_connection_recovery(cmd, sess);
 
                 spin_unlock(&cr->conn_recovery_cmd_lock);
-                if (!(cmd->se_cmd.se_cmd_flags & SCF_SE_LUN_CMD))
-                        iscsit_release_cmd(cmd);
-                else
-                        transport_generic_free_cmd(&cmd->se_cmd, 1);
+                iscsit_free_cmd(cmd);
                 spin_lock(&cr->conn_recovery_cmd_lock);
         }
         spin_unlock(&cr->conn_recovery_cmd_lock);
@@ -313,10 +304,7 @@ int iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(struct iscsi_conn *conn)
                 list_del(&cmd->i_list);
 
                 spin_unlock_bh(&conn->cmd_lock);
-                if (!(cmd->se_cmd.se_cmd_flags & SCF_SE_LUN_CMD))
-                        iscsit_release_cmd(cmd);
-                else
-                        transport_generic_free_cmd(&cmd->se_cmd, 1);
+                iscsit_free_cmd(cmd);
                 spin_lock_bh(&conn->cmd_lock);
         }
         spin_unlock_bh(&conn->cmd_lock);
@@ -369,11 +357,7 @@ int iscsit_prepare_cmds_for_realligance(struct iscsi_conn *conn)
 
                         list_del(&cmd->i_list);
                         spin_unlock_bh(&conn->cmd_lock);
-
-                        if (!(cmd->se_cmd.se_cmd_flags & SCF_SE_LUN_CMD))
-                                iscsit_release_cmd(cmd);
-                        else
-                                transport_generic_free_cmd(&cmd->se_cmd, 1);
+                        iscsit_free_cmd(cmd);
                         spin_lock_bh(&conn->cmd_lock);
                         continue;
                 }
@@ -393,11 +377,7 @@ int iscsit_prepare_cmds_for_realligance(struct iscsi_conn *conn)
                      (cmd->cmd_sn >= conn->sess->exp_cmd_sn)) {
                         list_del(&cmd->i_list);
                         spin_unlock_bh(&conn->cmd_lock);
-
-                        if (!(cmd->se_cmd.se_cmd_flags & SCF_SE_LUN_CMD))
-                                iscsit_release_cmd(cmd);
-                        else
-                                transport_generic_free_cmd(&cmd->se_cmd, 1);
+                        iscsit_free_cmd(cmd);
                         spin_lock_bh(&conn->cmd_lock);
                         continue;
                 }
@@ -422,8 +402,7 @@ int iscsit_prepare_cmds_for_realligance(struct iscsi_conn *conn)
 
                 iscsit_free_all_datain_reqs(cmd);
 
-                if (cmd->se_cmd.se_cmd_flags & SCF_SE_LUN_CMD)
-                        transport_wait_for_tasks(&cmd->se_cmd);
+                transport_wait_for_tasks(&cmd->se_cmd);
                 /*
                  * Add the struct iscsi_cmd to the connection recovery cmd list
                  */
diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c
index c4be6223b9cc..02348f727bd4 100644
--- a/drivers/target/iscsi/iscsi_target_util.c
+++ b/drivers/target/iscsi/iscsi_target_util.c
@@ -840,6 +840,23 @@ void iscsit_release_cmd(struct iscsi_cmd *cmd)
         kmem_cache_free(lio_cmd_cache, cmd);
 }
 
+void iscsit_free_cmd(struct iscsi_cmd *cmd)
+{
+        /*
+         * Determine if a struct se_cmd is assoicated with
+         * this struct iscsi_cmd.
+         */
+        switch (cmd->iscsi_opcode) {
+        case ISCSI_OP_SCSI_CMD:
+        case ISCSI_OP_SCSI_TMFUNC:
+                transport_generic_free_cmd(&cmd->se_cmd, 1);
+                break;
+        default:
+                iscsit_release_cmd(cmd);
+                break;
+        }
+}
+
 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 {
         spin_lock_bh(&sess->session_usage_lock);
diff --git a/drivers/target/iscsi/iscsi_target_util.h b/drivers/target/iscsi/iscsi_target_util.h
index 2cd49d607bda..835bf7de0281 100644
--- a/drivers/target/iscsi/iscsi_target_util.h
+++ b/drivers/target/iscsi/iscsi_target_util.h
@@ -30,6 +30,7 @@ extern struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_c
 extern void iscsit_remove_cmd_from_tx_queues(struct iscsi_cmd *, struct iscsi_conn *);
 extern void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *);
 extern void iscsit_release_cmd(struct iscsi_cmd *);
+extern void iscsit_free_cmd(struct iscsi_cmd *);
 extern int iscsit_check_session_usage_count(struct iscsi_session *);
 extern void iscsit_dec_session_usage_count(struct iscsi_session *);
 extern void iscsit_inc_session_usage_count(struct iscsi_session *);