scst: Remove redundant values and simplify known conditions

Remove overwritten initial values, unused offsets and zero-bit flag
operands. Derive the saved sense length from its captured value and rely
on C zero initialization for static-duration userspace objects. The FC
copy path remains unconditional because its buffers outlive the request.

Select CRC availability with the same four CONFIG predicates and use
else for a negative SRP residual only inside the nonzero-residual branch.
Group ternary bit tests and trim the PR filename's newline with strchr(),
retaining the empty-filename fallback. Manual review also identified the
overwritten QLogic tag initializer; every allocator branch assigns it.

Cppcheck reports:
  redundantAssignment: Variable 'tp' is reassigned a value before the
    old one has been used.
  unreadVariable: Variable 'sg_cnt' is assigned a value that is never used.
  unreadVariable: Variable 'data_offset' is assigned a value that is
    never used.
  clarifyCalculation: Clarify calculation precedence for '&' and '?'.
  ignoredReturnValue: Return value of function strsep() is not used.
  knownConditionTrueFalse: Condition '!crc32c' is always false.
  knownConditionTrueFalse: Condition 'resid<0' is always true.
  badBitmaskCheck: Operator '|' with one operand equal to zero is redundant.
It also marks the initial rc value in dev_user_process_cleanup() unread.

Checkpatch reports GLOBAL_INITIALISERS:
  do not initialise globals to false

fcst/ft_io.c

@@ -107,8 +107,6 @@ int ft_send_read_data(struct scst_cmd *cmd)
 #endif
 	}
 
-	/* no scatter/gather in skb for odd word length due to fc_seq_send() */
-	use_sg = !(remaining % 4) && lport->sg_supp;
 	/*
 	 * Note: since libfc_function_template.seq_send() sends frames
 	 * asynchronously and since the SCST data buffer is freed as soon as

iscsi-scst/kernel/digest.c

@@ -26,17 +26,13 @@
 
 void digest_alg_available(int *val)
 {
-#if defined(CONFIG_LIBCRC32C_MODULE) || defined(CONFIG_LIBCRC32C) ||	\
-	defined(CONFIG_CRC32_MODULE) || defined(CONFIG_CRC32)
-	int crc32c = 1;
-#else
-	int crc32c = 0;
-#endif
-
-	if ((*val & DIGEST_CRC32C) && !crc32c) {
+#if !defined(CONFIG_LIBCRC32C_MODULE) && !defined(CONFIG_LIBCRC32C) && \
+	!defined(CONFIG_CRC32_MODULE) && !defined(CONFIG_CRC32)
+	if (*val & DIGEST_CRC32C) {
 		PRINT_ERROR("CRC32C digest algorithm not available in kernel");
 		*val &= ~DIGEST_CRC32C;
 	}
+#endif
 }
 
 /**

iscsi-scst/kernel/isert-scst/iser_pdu.c

@@ -268,7 +268,6 @@ int isert_prepare_rdma(struct isert_cmnd *isert_pdu,
 	}
 
 	buff_offset = 0;
-	sg_cnt = 0;
 	for (wr_cnt = 0, sg_offset = 0; sg_offset < isert_buf->sg_cnt;
 	     ++wr_cnt) {
 		sg_cnt = min((int)isert_conn->max_sge,

iscsi-scst/kernel/isert-scst/iser_rdma.c

@@ -286,7 +286,6 @@ static void isert_rx_pdu_parse_headers(struct isert_cmnd *isert_pdu)
 	u8 *addr = isert_buf->addr;
 	struct isert_hdr *isert_hdr = (struct isert_hdr *)addr;
 	struct iscsi_hdr *bhs = (struct iscsi_hdr *)(addr + sizeof(*isert_hdr));
-	unsigned int data_offset = ISER_HDRS_SZ;
 	unsigned int ahssize;
 
 	TRACE_ENTRY();
@@ -317,7 +316,6 @@ static void isert_rx_pdu_parse_headers(struct isert_cmnd *isert_pdu)
 		isert_pdu->ahs = NULL;
 	} else {
 		isert_pdu->ahs = addr + ISER_HDRS_SZ;
-		data_offset += ahssize;
 	}
 	iscsi_cmnd->pdu.ahs = isert_pdu->ahs;
 

iscsi-scst/usr/log.c

@@ -24,7 +24,7 @@
 #include "iscsid.h"
 
 int log_daemon = 1;
-int log_level = 0;
+int log_level;
 
 void log_init(void)
 {

qla2x00t-32gbit/qla2x00-target/scst_qla2xxx.c

@@ -486,7 +486,7 @@ static struct qla_tgt_cmd *sqa_qla2xxx_get_cmd(struct fc_port *sess)
 	struct sqa_scst_tgt *sqa_tgt =
 		(struct sqa_scst_tgt *)sess->vha->vha_tgt.target_lport_ptr;
 	struct qla_tgt_cmd *cmd;
-	int tag = -ENOENT;
+	int tag;
 
 #if QLT_USE_PERCPU_IDA
 	tag = percpu_ida_alloc(&sqa_tgt->tgt_tag_pool, TASK_RUNNING);

scst/src/dev_handlers/scst_user_main.c

@@ -3834,7 +3834,7 @@ SCST_KUNIT_VISIBLE
 int dev_user_process_cleanup(struct scst_user_dev *dev)
 {
 	struct scst_user_cmd *ucmd;
-	int rc = 0, res = 1;
+	int rc, res = 1;
 
 	TRACE_ENTRY();
 

scst/src/dev_handlers/scst_vdisk_main.c

@@ -1869,7 +1869,7 @@ static enum compl_status_e vdisk_exec_format_unit(struct vdisk_cmd_params *p)
 				break;
 			default:
 				scst_set_invalid_field_in_parm_list(cmd, 0,
-					SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+					SCST_INVAL_FIELD_BIT_OFFS_VALID);
 				goto out;
 			}
 			break;
@@ -1877,7 +1877,7 @@ static enum compl_status_e vdisk_exec_format_unit(struct vdisk_cmd_params *p)
 			switch (prot_usage) {
 			default:
 				scst_set_invalid_field_in_parm_list(cmd, 0,
-					SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+					SCST_INVAL_FIELD_BIT_OFFS_VALID);
 				goto out;
 			}
 			break;
@@ -1888,7 +1888,7 @@ static enum compl_status_e vdisk_exec_format_unit(struct vdisk_cmd_params *p)
 				break;
 			default:
 				scst_set_invalid_field_in_parm_list(cmd, 0,
-					SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+					SCST_INVAL_FIELD_BIT_OFFS_VALID);
 				goto out;
 			}
 			break;
@@ -1902,7 +1902,7 @@ static enum compl_status_e vdisk_exec_format_unit(struct vdisk_cmd_params *p)
 				break;
 			default:
 				scst_set_invalid_field_in_parm_list(cmd, 0,
-					SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+					SCST_INVAL_FIELD_BIT_OFFS_VALID);
 				goto out;
 			}
 			break;
@@ -3495,7 +3495,7 @@ static enum compl_status_e vdisk_exec_unmap(struct vdisk_cmd_params *p)
 
 	if (unlikely(cmd->cdb[1] & 1)) {
 		TRACE_DBG("ANCHOR not supported");
-		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		goto out;
 	}
 
@@ -4402,7 +4402,7 @@ out:
 
 out_not_sup:
 	TRACE(TRACE_MINOR, "MODE SENSE: Unsupported page %x", pcode);
-	scst_set_invalid_field_in_cdb(cmd, 2, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+	scst_set_invalid_field_in_cdb(cmd, 2, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 	goto out_put;
 }
 
@@ -4598,7 +4598,7 @@ static void vdisk_caching_m_pg_select(unsigned char *p, struct scst_vdisk_dev *v
 
 	if (save && (!vdev_saved_mode_pages_enabled || virt_dev->nv_cache)) {
 		TRACE(TRACE_MINOR | TRACE_SCSI, "MODE SELECT: saved cache page not supported");
-		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		goto out;
 	}
 
@@ -4710,7 +4710,7 @@ static enum compl_status_e vdisk_exec_mode_select(struct vdisk_cmd_params *p)
 			TRACE(TRACE_MINOR, "MODE SELECT: Invalid request %x",
 			      address[offset] & 0x3f);
 			scst_set_invalid_field_in_parm_list(cmd, offset,
-							    SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+							    SCST_INVAL_FIELD_BIT_OFFS_VALID);
 			goto out_put;
 		}
 		offset += address[offset + 1];
@@ -4731,7 +4731,7 @@ static enum compl_status_e vdisk_exec_log(struct vdisk_cmd_params *p)
 	TRACE_ENTRY();
 
 	/* No log pages are supported */
-	scst_set_invalid_field_in_cdb(cmd, 2, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+	scst_set_invalid_field_in_cdb(cmd, 2, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 
 	TRACE_EXIT();
 	return CMD_SUCCEEDED;
@@ -4882,7 +4882,7 @@ out:
 static enum compl_status_e vdisk_exec_get_lba_status(struct vdisk_cmd_params *p)
 {
 	/* Changing it don't forget to add it to vdisk_opcode_descriptors! */
-	scst_set_invalid_field_in_cdb(p->cmd, 1, 0 | SCST_INVAL_FIELD_BIT_OFFS_VALID);
+	scst_set_invalid_field_in_cdb(p->cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 	return CMD_SUCCEEDED;
 }
 
@@ -4896,7 +4896,7 @@ enum compl_status_e vdisk_exec_sai_16(struct vdisk_cmd_params *p)
 	case SAI_GET_LBA_STATUS:
 		return vdisk_exec_get_lba_status(p);
 	}
-	scst_set_invalid_field_in_cdb(p->cmd, 1, 0 | SCST_INVAL_FIELD_BIT_OFFS_VALID);
+	scst_set_invalid_field_in_cdb(p->cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 	return CMD_SUCCEEDED;
 }
 

scst/src/scst_copy_mgr.c

@@ -582,7 +582,7 @@ static void scst_cm_prepare_final_sense(struct scst_cmd *ec_cmd)
 	int d_sense = scst_get_cmd_dev_d_sense(ec_cmd);
 	bool copy_sense = false;
 	int sense_to_copy = ec_cmd->sense_valid_len;
-	int sense_len = ec_cmd->sense_valid_len;
+	int sense_len = sense_to_copy;
 
 	TRACE_ENTRY();
 
@@ -2228,7 +2228,7 @@ enum scst_exec_res scst_cm_rcv_copy_res_exec(struct scst_cmd *cmd)
 	default:
 		TRACE(TRACE_MINOR, "%s: action %d not supported",
 		      cmd->op_name, action);
-		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		break;
 	}
 
@@ -2970,7 +2970,7 @@ static int scst_cm_parse_id_tgt_descr(struct scst_cmd *cmd, const uint8_t *seg,
 		PRINT_WARNING("PERIPHERAL DEVICE TYPE %d not supported",
 			      seg[1] & 0xF);
 		scst_set_invalid_field_in_parm_list(cmd, offs + 1,
-						    SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+						    SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		goto out_err;
 	}
 
@@ -3203,7 +3203,6 @@ skip_fcmd_create:
 					sBUG();
 					break;
 				}
-				tp = t;
 			}
 			tp = t;
 		}

scst/src/scst_event.c

@@ -1113,8 +1113,7 @@ int scst_event_init(void)
 
 	TRACE_ENTRY();
 
-	scst_event_wq = alloc_workqueue("scst_event_wq", 0
-					| WQ_UNBOUND,
+	scst_event_wq = alloc_workqueue("scst_event_wq", WQ_UNBOUND,
 					0);
 	if (unlikely(!scst_event_wq)) {
 		PRINT_ERROR("Failed to allocate scst_event_wq");

scst/src/scst_lib.c

@@ -7428,7 +7428,7 @@ struct scst_session *scst_alloc_session(struct scst_tgt *tgt, gfp_t gfp_mask,
 		 * To do: remove higher order allocation from the code below
 		 * for the GFP_ATOMIC case.
 		 */
-		sess->lat_stats = gfp_mask & GFP_ATOMIC ?
+		sess->lat_stats = (gfp_mask & GFP_ATOMIC) ?
 			kzalloc_obj(*sess->lat_stats, gfp_mask) :
 			vzalloc(sizeof(*sess->lat_stats));
 		if (!sess->lat_stats)
@@ -12118,7 +12118,7 @@ static int get_cdb_info_ext_copy(struct scst_cmd *cmd,
 		PRINT_WARNING("Not supported %s service action 0x%x",
 			scst_get_opcode_name(cmd), cmd->cdb[1]);
 		scst_set_invalid_field_in_cdb(cmd, 1,
-			0 | SCST_INVAL_FIELD_BIT_OFFS_VALID);
+			SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		return 1;
 	}
 
@@ -15692,8 +15692,7 @@ int __init scst_lib_init(void)
 
 	scst_scsi_op_list_init();
 
-	scst_release_acg_wq = alloc_workqueue("scst_release_acg", 0
-					      | WQ_UNBOUND,
+	scst_release_acg_wq = alloc_workqueue("scst_release_acg", WQ_UNBOUND,
 					      0);
 	if (unlikely(!scst_release_acg_wq)) {
 		PRINT_ERROR("Failed to allocate scst_release_acg_wq");

scst/src/scst_local_cmd.c

@@ -303,7 +303,7 @@ static enum scst_exec_res scst_exec_set_tpgs(struct scst_cmd *cmd)
 		PRINT_ERROR("SET TARGET PORT GROUPS: not explicit ALUA mode (dev %s)",
 			    dev->virt_name);
 		/* Invalid opcode, i.e. SA field */
-		scst_set_invalid_field_in_cdb(cmd, 1, 0 | SCST_INVAL_FIELD_BIT_OFFS_VALID);
+		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		goto out;
 	}
 
@@ -415,7 +415,7 @@ static enum scst_exec_res scst_report_supported_opcodes(struct scst_cmd *cmd)
 					      req_opcode, cmd->dev->virt_name,
 					      cmd->sess->initiator_name);
 					scst_set_invalid_field_in_cdb(cmd, 2,
-								      SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+								      SCST_INVAL_FIELD_BIT_OFFS_VALID);
 					goto out_compl;
 				}
 				buf_len = 4 + op->od_cdb_size;
@@ -442,7 +442,7 @@ static enum scst_exec_res scst_report_supported_opcodes(struct scst_cmd *cmd)
 					      req_opcode, cmd->dev->virt_name,
 					      cmd->sess->initiator_name);
 					scst_set_invalid_field_in_cdb(cmd, 2,
-								      SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+								      SCST_INVAL_FIELD_BIT_OFFS_VALID);
 					goto out_compl;
 				}
 				if (req_sa != op->od_serv_action) {
@@ -465,7 +465,7 @@ static enum scst_exec_res scst_report_supported_opcodes(struct scst_cmd *cmd)
 	default:
 		PRINT_ERROR("REPORT SUPPORTED OPERATION CODES: REPORTING OPTIONS %x not supported (dev %s, initiator %s)",
 			    options, cmd->dev->virt_name, cmd->sess->initiator_name);
-		scst_set_invalid_field_in_cdb(cmd, 2, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+		scst_set_invalid_field_in_cdb(cmd, 2, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		goto out_compl;
 	}
 
@@ -842,7 +842,7 @@ out_done:
 	return SCST_EXEC_COMPLETED;
 
 out_unsup_act:
-	scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+	scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 	goto out_complete;
 }
 
@@ -970,7 +970,7 @@ enum scst_exec_res scst_persistent_reserve_out_local(struct scst_cmd *cmd)
 		scst_pr_register_and_move(cmd, buffer, buffer_size);
 		break;
 	default:
-		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		goto out_unlock;
 	}
 

scst/src/scst_pres.c

@@ -1882,7 +1882,7 @@ void scst_pr_reserve(struct scst_cmd *cmd, uint8_t *buffer, int buffer_size)
 
 	if (!scst_pr_type_valid(type)) {
 		TRACE_PR("Invalid reservation type %d", type);
-		scst_set_invalid_field_in_cdb(cmd, 2, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+		scst_set_invalid_field_in_cdb(cmd, 2, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		goto out;
 	}
 
@@ -2080,7 +2080,7 @@ static void scst_pr_do_preempt(struct scst_cmd *cmd, uint8_t *buffer, int buffer
 
 	if (!scst_pr_type_valid(type)) {
 		TRACE_PR("Invalid reservation type %d", type);
-		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+		scst_set_invalid_field_in_cdb(cmd, 1, SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		goto out;
 	}
 

scst/src/scst_sysfs.c

@@ -3222,8 +3222,9 @@ static ssize_t scst_dev_sysfs_pr_file_name_store(struct kobject *kobj, struct ko
 		PRINT_ERROR("Unable to kasprintf() PR file name");
 		goto out;
 	}
-	p = pr_file_name;
-	strsep(&p, "\n"); /* strip trailing whitespace */
+	p = strchr(pr_file_name, '\n');
+	if (p)
+		*p = '\0';
 	if (pr_file_name[0] == '\0') {
 		kfree(pr_file_name);
 		pr_file_name = kasprintf(GFP_KERNEL, "%s/%s", SCST_PR_DIR,

scst/src/scst_targ.c

@@ -1152,7 +1152,7 @@ int scst_parse_cmd(struct scst_cmd *cmd)
 		PRINT_ERROR("Linked commands are not supported (opcode %s)",
 			    scst_get_opcode_name(cmd));
 		scst_set_invalid_field_in_cdb(cmd, cmd->cdb_len - 1,
-					      SCST_INVAL_FIELD_BIT_OFFS_VALID | 0);
+					      SCST_INVAL_FIELD_BIT_OFFS_VALID);
 		goto out_done;
 	}
 

scst_local/scst_local.c

@@ -170,7 +170,7 @@ static int scst_local_get_sas_transport_id(struct scst_local_sess *sess, uint8_t
 		goto out;
 	}
 
-	tr_id[0] = 0x00 | SCSI_TRANSPORTID_PROTOCOLID_SAS;
+	tr_id[0] = SCSI_TRANSPORTID_PROTOCOLID_SAS;
 
 	/*
 	 * Assemble a valid SAS address = 0x5OOUUIIR12345678 ... Does SCST

srpt/src/ib_srpt.c

@@ -1649,14 +1649,14 @@ static int srpt_build_cmd_rsp(struct srpt_rdma_ch *ch,
 		if (scst_cmd_get_data_direction(cmd) & SCST_DATA_READ) {
 			if (resid > 0)
 				srp_rsp->flags |= SRP_RSP_FLAG_DIUNDER;
-			else if (resid < 0)
+			else
 				srp_rsp->flags |= SRP_RSP_FLAG_DIOVER;
 			srp_rsp->data_in_res_cnt = cpu_to_be32(abs(resid));
 		}
 		if (scst_cmd_get_data_direction(cmd) & SCST_DATA_WRITE) {
 			if (resid > 0)
 				srp_rsp->flags |= SRP_RSP_FLAG_DOUNDER;
-			else if (resid < 0)
+			else
 				srp_rsp->flags |= SRP_RSP_FLAG_DOOVER;
 			srp_rsp->data_out_res_cnt = cpu_to_be32(abs(resid));
 		}
@@ -2651,7 +2651,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
 		list_add_tail(&ch->ioctx_ring[i]->free_list, &ch->free_list);
 	}
 	if (!sdev->use_srq) {
-		u16 imm_data_offset = req->req_flags & SRP_IMMED_REQUESTED ?
+		u16 imm_data_offset = (req->req_flags & SRP_IMMED_REQUESTED) ?
 			be16_to_cpu(req->imm_data_offset) : 0;
 		u16 alignment_offset;
 		u32 req_sz;

usr/events/events.c

@@ -52,7 +52,7 @@ char *app_name;
 # endif
 #endif /* DEBUG */
 
-bool log_daemon = false; /* needed for the tracing infrastructure */
+bool log_daemon; /* needed for the tracing infrastructure */
 unsigned long trace_flag = DEFAULT_LOG_FLAGS;
 #endif /* defined(DEBUG) || defined(TRACING) */
 

usr/fileio/fileio.c

@@ -69,7 +69,7 @@ char *app_name;
 unsigned long trace_flag = DEFAULT_LOG_FLAGS;
 #endif /* defined(DEBUG) || defined(TRACING) */
 
-bool log_daemon = false;
+bool log_daemon;
 
 #define DEF_BLOCK_SHIFT		9
 #define THREADS			7