Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

Pull SCSI target updates from Nicholas Bellinger:
 "The most notable item is IBM virtual SCSI target driver, that was
  originally ported to target-core back in 2010 by Tomo-san, and has
  been brought forward to v4.x code by Bryant Ly, Michael Cyr and co
  over the last months.

  Also included are two ORDERED task related bug-fixes Bryant + Michael
  found along the way using ibmvscsis with AIX guests, plus a few
  miscellaneous target-core + iscsi-target bug-fixes with associated
  stable tags"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target: fix spelling mistake: "limitiation" -> "limitation"
  target: Fix residual overflow handling in target_complete_cmd_with_length
  tcm_fc: set and unset FCP_SPPF_TARG_FCN
  iscsi-target: Fix panic when adding second TCP connection to iSCSI session
  ibmvscsis: Initial commit of IBM VSCSI Tgt Driver
  target: Fix ordered task CHECK_CONDITION early exception handling
  target: Fix ordered task target_setup_cmd_from_cdb exception hang
  target: Fix max_unmap_lba_count calc overflow
  target: Fix race between iscsi-target connection shutdown + ABORT_TASK
  target: Fix missing complete during ABORT_TASK + CMD_T_FABRIC_STOP

9 files changed, 89 insertions, 53 deletions

diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index 50f3d3a0dd7b..39b928c2849d 100644
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -492,7 +492,8 @@ void iscsit_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
 	bool scsi_cmd = (cmd->iscsi_opcode == ISCSI_OP_SCSI_CMD);
 
 	spin_lock_bh(&conn->cmd_lock);
-	if (!list_empty(&cmd->i_conn_node))
+	if (!list_empty(&cmd->i_conn_node) &&
+	    !(cmd->se_cmd.transport_state & CMD_T_FABRIC_STOP))
 		list_del_init(&cmd->i_conn_node);
 	spin_unlock_bh(&conn->cmd_lock);
 
@@ -4034,6 +4035,7 @@ int iscsi_target_rx_thread(void *arg)
 
 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
 {
+	LIST_HEAD(tmp_list);
 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
 	struct iscsi_session *sess = conn->sess;
 	/*
@@ -4042,18 +4044,26 @@ static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
 	 * has been reset -> returned sleeping pre-handler state.
 	 */
 	spin_lock_bh(&conn->cmd_lock);
-	list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_conn_node) {
+	list_splice_init(&conn->conn_cmd_list, &tmp_list);
 
+	list_for_each_entry(cmd, &tmp_list, i_conn_node) {
+		struct se_cmd *se_cmd = &cmd->se_cmd;
+
+		if (se_cmd->se_tfo != NULL) {
+			spin_lock(&se_cmd->t_state_lock);
+			se_cmd->transport_state |= CMD_T_FABRIC_STOP;
+			spin_unlock(&se_cmd->t_state_lock);
+		}
+	}
+	spin_unlock_bh(&conn->cmd_lock);
+
+	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
 		list_del_init(&cmd->i_conn_node);
-		spin_unlock_bh(&conn->cmd_lock);
 
 		iscsit_increment_maxcmdsn(cmd, sess);
-
 		iscsit_free_cmd(cmd, true);
 
-		spin_lock_bh(&conn->cmd_lock);
 	}
-	spin_unlock_bh(&conn->cmd_lock);
 }
 
 static void iscsit_stop_timers_for_cmds(
diff --git a/drivers/target/iscsi/iscsi_target_login.c b/drivers/target/iscsi/iscsi_target_login.c
index b5212f0f9571..adf419fa4291 100644
--- a/drivers/target/iscsi/iscsi_target_login.c
+++ b/drivers/target/iscsi/iscsi_target_login.c
@@ -1371,8 +1371,9 @@ static int __iscsi_target_login_thread(struct iscsi_np *np)
 	}
 	login->zero_tsih = zero_tsih;
 
-	conn->sess->se_sess->sup_prot_ops =
-		conn->conn_transport->iscsit_get_sup_prot_ops(conn);
+	if (conn->sess)
+		conn->sess->se_sess->sup_prot_ops =
+			conn->conn_transport->iscsit_get_sup_prot_ops(conn);
 
 	tpg = conn->tpg;
 	if (!tpg) {
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index a4046ca6e60d..6b423485c5d6 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -821,13 +821,15 @@ struct se_device *target_alloc_device(struct se_hba *hba, const char *name)
  * in ATA and we need to set TPE=1
  */
 bool target_configure_unmap_from_queue(struct se_dev_attrib *attrib,
-				       struct request_queue *q, int block_size)
+				       struct request_queue *q)
 {
+	int block_size = queue_logical_block_size(q);
+
 	if (!blk_queue_discard(q))
 		return false;
 
-	attrib->max_unmap_lba_count = (q->limits.max_discard_sectors << 9) /
-								block_size;
+	attrib->max_unmap_lba_count =
+		q->limits.max_discard_sectors >> (ilog2(block_size) - 9);
 	/*
 	 * Currently hardcoded to 1 in Linux/SCSI code..
 	 */
diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
index 75f0f08b2a34..d545993df18b 100644
--- a/drivers/target/target_core_file.c
+++ b/drivers/target/target_core_file.c
@@ -161,8 +161,7 @@ static int fd_configure_device(struct se_device *dev)
 			dev_size, div_u64(dev_size, fd_dev->fd_block_size),
 			fd_dev->fd_block_size);
 
-		if (target_configure_unmap_from_queue(&dev->dev_attrib, q,
-						      fd_dev->fd_block_size))
+		if (target_configure_unmap_from_queue(&dev->dev_attrib, q))
 			pr_debug("IFILE: BLOCK Discard support available,"
 				 " disabled by default\n");
 		/*
@@ -523,7 +522,7 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 	 */
 	if (cmd->data_length > FD_MAX_BYTES) {
 		pr_err("FILEIO: Not able to process I/O of %u bytes due to"
-		       "FD_MAX_BYTES: %u iovec count limitiation\n",
+		       "FD_MAX_BYTES: %u iovec count limitation\n",
 			cmd->data_length, FD_MAX_BYTES);
 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 	}
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 22af12f8b8eb..47cf6c977367 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -121,8 +121,7 @@ static int iblock_configure_device(struct se_device *dev)
 	dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q);
 	dev->dev_attrib.hw_queue_depth = q->nr_requests;
 
-	if (target_configure_unmap_from_queue(&dev->dev_attrib, q,
-					      dev->dev_attrib.hw_block_size))
+	if (target_configure_unmap_from_queue(&dev->dev_attrib, q))
 		pr_debug("IBLOCK: BLOCK Discard support available,"
 			 " disabled by default\n");
 
diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h
index fc91e85f54ba..e2c970a9d61c 100644
--- a/drivers/target/target_core_internal.h
+++ b/drivers/target/target_core_internal.h
@@ -146,6 +146,7 @@ sense_reason_t	target_cmd_size_check(struct se_cmd *cmd, unsigned int size);
 void	target_qf_do_work(struct work_struct *work);
 bool	target_check_wce(struct se_device *dev);
 bool	target_check_fua(struct se_device *dev);
+void	__target_execute_cmd(struct se_cmd *, bool);
 
 /* target_core_stat.c */
 void	target_stat_setup_dev_default_groups(struct se_device *);
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index a9057aa07176..04f616b3ba0a 100644
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -602,7 +602,7 @@ static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool succes
 	cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
 	spin_unlock_irq(&cmd->t_state_lock);
 
-	__target_execute_cmd(cmd);
+	__target_execute_cmd(cmd, false);
 
 	kfree(buf);
 	return ret;
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 5ab3967dda43..6094a6beddde 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -754,7 +754,15 @@ EXPORT_SYMBOL(target_complete_cmd);
 
 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 {
-	if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
+	if (scsi_status != SAM_STAT_GOOD) {
+		return;
+	}
+
+	/*
+	 * Calculate new residual count based upon length of SCSI data
+	 * transferred.
+	 */
+	if (length < cmd->data_length) {
 		if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 			cmd->residual_count += cmd->data_length - length;
 		} else {
@@ -763,6 +771,12 @@ void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int len
 		}
 
 		cmd->data_length = length;
+	} else if (length > cmd->data_length) {
+		cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
+		cmd->residual_count = length - cmd->data_length;
+	} else {
+		cmd->se_cmd_flags &= ~(SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT);
+		cmd->residual_count = 0;
 	}
 
 	target_complete_cmd(cmd, scsi_status);
@@ -1303,23 +1317,6 @@ target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
 
 	trace_target_sequencer_start(cmd);
 
-	/*
-	 * Check for an existing UNIT ATTENTION condition
-	 */
-	ret = target_scsi3_ua_check(cmd);
-	if (ret)
-		return ret;
-
-	ret = target_alua_state_check(cmd);
-	if (ret)
-		return ret;
-
-	ret = target_check_reservation(cmd);
-	if (ret) {
-		cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
-		return ret;
-	}
-
 	ret = dev->transport->parse_cdb(cmd);
 	if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
 		pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
@@ -1761,20 +1758,45 @@ queue_full:
 }
 EXPORT_SYMBOL(transport_generic_request_failure);
 
-void __target_execute_cmd(struct se_cmd *cmd)
+void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
 {
 	sense_reason_t ret;
 
-	if (cmd->execute_cmd) {
-		ret = cmd->execute_cmd(cmd);
-		if (ret) {
-			spin_lock_irq(&cmd->t_state_lock);
-			cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
-			spin_unlock_irq(&cmd->t_state_lock);
+	if (!cmd->execute_cmd) {
+		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		goto err;
+	}
+	if (do_checks) {
+		/*
+		 * Check for an existing UNIT ATTENTION condition after
+		 * target_handle_task_attr() has done SAM task attr
+		 * checking, and possibly have already defered execution
+		 * out to target_restart_delayed_cmds() context.
+		 */
+		ret = target_scsi3_ua_check(cmd);
+		if (ret)
+			goto err;
 
-			transport_generic_request_failure(cmd, ret);
+		ret = target_alua_state_check(cmd);
+		if (ret)
+			goto err;
+
+		ret = target_check_reservation(cmd);
+		if (ret) {
+			cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
+			goto err;
 		}
 	}
+
+	ret = cmd->execute_cmd(cmd);
+	if (!ret)
+		return;
+err:
+	spin_lock_irq(&cmd->t_state_lock);
+	cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
+	spin_unlock_irq(&cmd->t_state_lock);
+
+	transport_generic_request_failure(cmd, ret);
 }
 
 static int target_write_prot_action(struct se_cmd *cmd)
@@ -1819,6 +1841,8 @@ static bool target_handle_task_attr(struct se_cmd *cmd)
 	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
 		return false;
 
+	cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
+
 	/*
 	 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
 	 * to allow the passed struct se_cmd list of tasks to the front of the list.
@@ -1899,7 +1923,7 @@ void target_execute_cmd(struct se_cmd *cmd)
 		return;
 	}
 
-	__target_execute_cmd(cmd);
+	__target_execute_cmd(cmd, true);
 }
 EXPORT_SYMBOL(target_execute_cmd);
 
@@ -1923,7 +1947,7 @@ static void target_restart_delayed_cmds(struct se_device *dev)
 		list_del(&cmd->se_delayed_node);
 		spin_unlock(&dev->delayed_cmd_lock);
 
-		__target_execute_cmd(cmd);
+		__target_execute_cmd(cmd, true);
 
 		if (cmd->sam_task_attr == TCM_ORDERED_TAG)
 			break;
@@ -1941,6 +1965,9 @@ static void transport_complete_task_attr(struct se_cmd *cmd)
 	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
 		return;
 
+	if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
+		goto restart;
+
 	if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
 		atomic_dec_mb(&dev->simple_cmds);
 		dev->dev_cur_ordered_id++;
@@ -1957,7 +1984,7 @@ static void transport_complete_task_attr(struct se_cmd *cmd)
 		pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
 			 dev->dev_cur_ordered_id);
 	}
-
+restart:
 	target_restart_delayed_cmds(dev);
 }
 
@@ -2557,15 +2584,10 @@ static void target_release_cmd_kref(struct kref *kref)
 	bool fabric_stop;
 
 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
-	if (list_empty(&se_cmd->se_cmd_list)) {
-		spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
-		target_free_cmd_mem(se_cmd);
-		se_cmd->se_tfo->release_cmd(se_cmd);
-		return;
-	}
 
 	spin_lock(&se_cmd->t_state_lock);
-	fabric_stop = (se_cmd->transport_state & CMD_T_FABRIC_STOP);
+	fabric_stop = (se_cmd->transport_state & CMD_T_FABRIC_STOP) &&
+		      (se_cmd->transport_state & CMD_T_ABORTED);
 	spin_unlock(&se_cmd->t_state_lock);
 
 	if (se_cmd->cmd_wait_set || fabric_stop) {
diff --git a/drivers/target/tcm_fc/tfc_sess.c b/drivers/target/tcm_fc/tfc_sess.c
index f5186a744399..6ffbb603d912 100644
--- a/drivers/target/tcm_fc/tfc_sess.c
+++ b/drivers/target/tcm_fc/tfc_sess.c
@@ -91,6 +91,7 @@ static void ft_tport_delete(struct ft_tport *tport)
 
 	ft_sess_delete_all(tport);
 	lport = tport->lport;
+	lport->service_params &= ~FCP_SPPF_TARG_FCN;
 	BUG_ON(tport != lport->prov[FC_TYPE_FCP]);
 	RCU_INIT_POINTER(lport->prov[FC_TYPE_FCP], NULL);
 
@@ -110,6 +111,7 @@ void ft_lport_add(struct fc_lport *lport, void *arg)
 {
 	mutex_lock(&ft_lport_lock);
 	ft_tport_get(lport);
+	lport->service_params |= FCP_SPPF_TARG_FCN;
 	mutex_unlock(&ft_lport_lock);
 }