target: Address legacy PYX_TRANSPORT_* return code breakage

This patch removes legacy usage of PYX_TRANSPORT_* return codes in a number
of locations and addresses cases where transport_generic_request_failure()
was returning the incorrect sense upon CHECK_CONDITION status after the
v3.1 converson to use errno return codes.

This includes the conversion of transport_generic_request_failure() to
process cmd->scsi_sense_reason and handle extra TCM_RESERVATION_CONFLICT
before calling transport_send_check_condition_and_sense() to queue up
response status.  It also drops PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES legacy
usgae, and returns TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE w/ a response
for these cases.

transport_generic_allocate_tasks(), transport_generic_new_cmd(), backend
SCF_SCSI_DATA_SG_IO_CDB ->do_task(), and emulated ->execute_task() have
all been updated to set se_cmd->scsi_sense_reason and return errno codes
universally upon failure.  This includes cmd->scsi_sense_reason assignment
in target_core_alua.c, target_core_pr.c and target_core_cdb.c emulation code.

Finally it updates fabric modules to remove the legacy usage, and for
TFO->new_cmd_map() callers forwards return values outside of fabric code.
iscsi-target has also been updated to remove a handful of special cases
related to the cleanup and signaling QUEUE_FULL handling w/ ft_write_pending()

(v2: Drop extra SCF_SCSI_CDB_EXCEPTION check during failure from
     transport_generic_new_cmd, and re-add missing task->task_error_status
     assignment in transport_complete_task)

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

1 files changed, 16 insertions, 9 deletions

diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_core_alua.c
index 88f2ad43ec8b..cd61331c1482 100644
--- a/drivers/target/target_core_alua.c
+++ b/drivers/target/target_core_alua.c
@@ -191,9 +191,10 @@ int target_emulate_set_target_port_groups(struct se_task *task)
 	int alua_access_state, primary = 0, rc;
 	u16 tg_pt_id, rtpi;
 
-	if (!l_port)
-		return PYX_TRANSPORT_LU_COMM_FAILURE;
-
+	if (!l_port) {
+		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		return -EINVAL;
+	}
 	buf = transport_kmap_first_data_page(cmd);
 
 	/*
@@ -203,7 +204,8 @@ int target_emulate_set_target_port_groups(struct se_task *task)
 	l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
 	if (!l_tg_pt_gp_mem) {
 		pr_err("Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
-		rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+		cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
+		rc = -EINVAL;
 		goto out;
 	}
 	spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
@@ -211,7 +213,8 @@ int target_emulate_set_target_port_groups(struct se_task *task)
 	if (!l_tg_pt_gp) {
 		spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 		pr_err("Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
-		rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+		cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
+		rc = -EINVAL;
 		goto out;
 	}
 	rc = (l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA);
@@ -220,7 +223,8 @@ int target_emulate_set_target_port_groups(struct se_task *task)
 	if (!rc) {
 		pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
 				" while TPGS_EXPLICT_ALUA is disabled\n");
-		rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+		cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
+		rc = -EINVAL;
 		goto out;
 	}
 
@@ -245,7 +249,8 @@ int target_emulate_set_target_port_groups(struct se_task *task)
 			 * REQUEST, and the additional sense code set to INVALID
 			 * FIELD IN PARAMETER LIST.
 			 */
-			rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
+			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
+			rc = -EINVAL;
 			goto out;
 		}
 		rc = -1;
@@ -298,7 +303,8 @@ int target_emulate_set_target_port_groups(struct se_task *task)
 			 * throw an exception with ASCQ: INVALID_PARAMETER_LIST
 			 */
 			if (rc != 0) {
-				rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
+				cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
+				rc = -EINVAL;
 				goto out;
 			}
 		} else {
@@ -335,7 +341,8 @@ int target_emulate_set_target_port_groups(struct se_task *task)
 			 * INVALID_PARAMETER_LIST
 			 */
 			if (rc != 0) {
-				rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
+				cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
+				rc = -EINVAL;
 				goto out;
 			}
 		}