Merge patch series "target: TMF and recovery fixes"

Mike Christie <michael.christie@oracle.com> says:

The following patches apply over Martin's 6.4 branches and Linus's tree.
They fix a couple regressions in iscsit that occur when there are TMRs
executing and a connection is closed. It also includes Dimitry's fixes in
related code paths for cmd cleanup when ERL2 is used and the write pending
hang during conn cleanup.

This version of the patchset brings it back to just regressions and fixes
for bugs we have a lot of users hitting. I'm going to fix isert and get it
hooked into iscsit properly in a second patchset, because this one was
getting so large. I've also moved my cleanup type of patches for a 3rd
patchset.

Link: https://lore.kernel.org/r/20230319015620.96006-1-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Author: martinkpetersen

drivers/infiniband/ulp/isert/ib_isert.c

@@ -2506,8 +2506,8 @@ isert_wait4cmds(struct iscsit_conn *conn)
 	isert_info("iscsit_conn %p\n", conn);
 
 	if (conn->sess) {
-		target_stop_session(conn->sess->se_sess);
-		target_wait_for_sess_cmds(conn->sess->se_sess);
+		target_stop_cmd_counter(conn->cmd_cnt);
+		target_wait_for_cmds(conn->cmd_cnt);
 	}
 }
 

drivers/target/iscsi/iscsi_target.c

@@ -26,6 +26,7 @@
 #include <target/target_core_base.h>
 #include <target/target_core_fabric.h>
 
+#include <target/target_core_backend.h>
 #include <target/iscsi/iscsi_target_core.h>
 #include "iscsi_target_parameters.h"
 #include "iscsi_target_seq_pdu_list.h"
@@ -1190,9 +1191,10 @@ int iscsit_setup_scsi_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 	 */
 	__target_init_cmd(&cmd->se_cmd, &iscsi_ops,
-			 conn->sess->se_sess, be32_to_cpu(hdr->data_length),
-			 cmd->data_direction, sam_task_attr,
-			 cmd->sense_buffer + 2, scsilun_to_int(&hdr->lun));
+			  conn->sess->se_sess, be32_to_cpu(hdr->data_length),
+			  cmd->data_direction, sam_task_attr,
+			  cmd->sense_buffer + 2, scsilun_to_int(&hdr->lun),
+			  conn->cmd_cnt);
 
 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
@@ -2055,7 +2057,8 @@ iscsit_handle_task_mgt_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
 	__target_init_cmd(&cmd->se_cmd, &iscsi_ops,
 			  conn->sess->se_sess, 0, DMA_NONE,
 			  TCM_SIMPLE_TAG, cmd->sense_buffer + 2,
-			  scsilun_to_int(&hdr->lun));
+			  scsilun_to_int(&hdr->lun),
+			  conn->cmd_cnt);
 
 	target_get_sess_cmd(&cmd->se_cmd, true);
 
@@ -4218,21 +4221,33 @@ static void iscsit_release_commands_from_conn(struct iscsit_conn *conn)
 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
 		struct se_cmd *se_cmd = &cmd->se_cmd;
 
-		if (se_cmd->se_tfo != NULL) {
-			spin_lock_irq(&se_cmd->t_state_lock);
-			if (se_cmd->transport_state & CMD_T_ABORTED) {
+		if (!se_cmd->se_tfo)
+			continue;
+
+		spin_lock_irq(&se_cmd->t_state_lock);
+		if (se_cmd->transport_state & CMD_T_ABORTED) {
+			if (!(se_cmd->transport_state & CMD_T_TAS))
 				/*
 				 * LIO's abort path owns the cleanup for this,
 				 * so put it back on the list and let
 				 * aborted_task handle it.
 				 */
 				list_move_tail(&cmd->i_conn_node,
 					       &conn->conn_cmd_list);
-			} else {
-				se_cmd->transport_state |= CMD_T_FABRIC_STOP;
-			}
+		} else {
+			se_cmd->transport_state |= CMD_T_FABRIC_STOP;
+		}
+
+		if (cmd->se_cmd.t_state == TRANSPORT_WRITE_PENDING) {
+			/*
+			 * We never submitted the cmd to LIO core, so we have
+			 * to tell LIO to perform the completion process.
+			 */
 			spin_unlock_irq(&se_cmd->t_state_lock);
+			target_complete_cmd(&cmd->se_cmd, SAM_STAT_TASK_ABORTED);
+			continue;
 		}
+		spin_unlock_irq(&se_cmd->t_state_lock);
 	}
 	spin_unlock_bh(&conn->cmd_lock);
 
@@ -4243,6 +4258,16 @@ static void iscsit_release_commands_from_conn(struct iscsit_conn *conn)
 		iscsit_free_cmd(cmd, true);
 
 	}
+
+	/*
+	 * Wait on commands that were cleaned up via the aborted_task path.
+	 * LLDs that implement iscsit_wait_conn will already have waited for
+	 * commands.
+	 */
+	if (!conn->conn_transport->iscsit_wait_conn) {
+		target_stop_cmd_counter(conn->cmd_cnt);
+		target_wait_for_cmds(conn->cmd_cnt);
+	}
 }
 
 static void iscsit_stop_timers_for_cmds(
@@ -4517,6 +4542,9 @@ int iscsit_close_session(struct iscsit_session *sess, bool can_sleep)
 	iscsit_stop_time2retain_timer(sess);
 	spin_unlock_bh(&se_tpg->session_lock);
 
+	if (sess->sess_ops->ErrorRecoveryLevel == 2)
+		iscsit_free_connection_recovery_entries(sess);
+
 	/*
 	 * transport_deregister_session_configfs() will clear the
 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
@@ -4540,9 +4568,6 @@ int iscsit_close_session(struct iscsit_session *sess, bool can_sleep)
 
 	transport_deregister_session(sess->se_sess);
 
-	if (sess->sess_ops->ErrorRecoveryLevel == 2)
-		iscsit_free_connection_recovery_entries(sess);
-
 	iscsit_free_all_ooo_cmdsns(sess);
 
 	spin_lock_bh(&se_tpg->session_lock);

drivers/target/iscsi/iscsi_target_login.c

@@ -1147,8 +1147,14 @@ static struct iscsit_conn *iscsit_alloc_conn(struct iscsi_np *np)
 		goto free_conn_cpumask;
 	}
 
+	conn->cmd_cnt = target_alloc_cmd_counter();
+	if (!conn->cmd_cnt)
+		goto free_conn_allowed_cpumask;
+
 	return conn;
 
+free_conn_allowed_cpumask:
+	free_cpumask_var(conn->allowed_cpumask);
 free_conn_cpumask:
 	free_cpumask_var(conn->conn_cpumask);
 free_conn_ops:
@@ -1162,6 +1168,7 @@ static struct iscsit_conn *iscsit_alloc_conn(struct iscsi_np *np)
 
 void iscsit_free_conn(struct iscsit_conn *conn)
 {
+	target_free_cmd_counter(conn->cmd_cnt);
 	free_cpumask_var(conn->allowed_cpumask);
 	free_cpumask_var(conn->conn_cpumask);
 	kfree(conn->conn_ops);

drivers/target/target_core_device.c

@@ -741,6 +741,7 @@ struct se_device *target_alloc_device(struct se_hba *hba, const char *name)
 	spin_lock_init(&dev->t10_alua.lba_map_lock);
 
 	INIT_WORK(&dev->delayed_cmd_work, target_do_delayed_work);
+	mutex_init(&dev->lun_reset_mutex);
 
 	dev->t10_wwn.t10_dev = dev;
 	/*

drivers/target/target_core_internal.h

@@ -139,7 +139,6 @@ int	init_se_kmem_caches(void);
 void	release_se_kmem_caches(void);
 u32	scsi_get_new_index(scsi_index_t);
 void	transport_subsystem_check_init(void);
-void	transport_uninit_session(struct se_session *);
 unsigned char *transport_dump_cmd_direction(struct se_cmd *);
 void	transport_dump_dev_state(struct se_device *, char *, int *);
 void	transport_dump_dev_info(struct se_device *, struct se_lun *,

drivers/target/target_core_tmr.c

@@ -188,14 +188,23 @@ static void core_tmr_drain_tmr_list(
 	 * LUN_RESET tmr..
 	 */
 	spin_lock_irqsave(&dev->se_tmr_lock, flags);
-	if (tmr)
-		list_del_init(&tmr->tmr_list);
 	list_for_each_entry_safe(tmr_p, tmr_pp, &dev->dev_tmr_list, tmr_list) {
+		if (tmr_p == tmr)
+			continue;
+
 		cmd = tmr_p->task_cmd;
 		if (!cmd) {
 			pr_err("Unable to locate struct se_cmd for TMR\n");
 			continue;
 		}
+
+		/*
+		 * We only execute one LUN_RESET at a time so we can't wait
+		 * on them below.
+		 */
+		if (tmr_p->function == TMR_LUN_RESET)
+			continue;
+
 		/*
 		 * If this function was called with a valid pr_res_key
 		 * parameter (eg: for PROUT PREEMPT_AND_ABORT service action
@@ -379,14 +388,25 @@ int core_tmr_lun_reset(
 				tmr_nacl->initiatorname);
 		}
 	}
+
+
+	/*
+	 * We only allow one reset or preempt and abort to execute at a time
+	 * to prevent one call from claiming all the cmds causing a second
+	 * call from returning while cmds it should have waited on are still
+	 * running.
+	 */
+	mutex_lock(&dev->lun_reset_mutex);
+
 	pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n",
 		(preempt_and_abort_list) ? "Preempt" : "TMR",
 		dev->transport->name, tas);
-
 	core_tmr_drain_tmr_list(dev, tmr, preempt_and_abort_list);
 	core_tmr_drain_state_list(dev, prout_cmd, tmr_sess, tas,
 				preempt_and_abort_list);
 
+	mutex_unlock(&dev->lun_reset_mutex);
+
 	/*
 	 * Clear any legacy SPC-2 reservation when called during
 	 * LOGICAL UNIT RESET

drivers/target/target_core_tpg.c

@@ -329,7 +329,7 @@ static void target_shutdown_sessions(struct se_node_acl *acl)
 restart:
 	spin_lock_irqsave(&acl->nacl_sess_lock, flags);
 	list_for_each_entry(sess, &acl->acl_sess_list, sess_acl_list) {
-		if (atomic_read(&sess->stopped))
+		if (sess->cmd_cnt && atomic_read(&sess->cmd_cnt->stopped))
 			continue;
 
 		list_del_init(&sess->sess_acl_list);