scsi: iscsi: Fix shost->max_id use

The iscsi offload drivers are setting the shost->max_id to the max number
of sessions they support. The problem is that max_id is not the max number
of targets but the highest identifier the targets can have. To use it to
limit the number of targets we need to set it to max sessions - 1, or we
can end up with a session we might not have preallocated resources for.

Link: https://lore.kernel.org/r/20210525181821.7617-15-michael.christie@oracle.comReviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/be2iscsi/be_main.c

@@ -416,7 +416,7 @@ static struct beiscsi_hba *beiscsi_hba_alloc(struct pci_dev *pcidev)
 			"beiscsi_hba_alloc - iscsi_host_alloc failed\n");
 		return NULL;
 	}
-	shost->max_id = BE2_MAX_SESSIONS;
+	shost->max_id = BE2_MAX_SESSIONS - 1;
 	shost->max_channel = 0;
 	shost->max_cmd_len = BEISCSI_MAX_CMD_LEN;
 	shost->max_lun = BEISCSI_NUM_MAX_LUN;
@@ -5316,7 +5316,7 @@ static int beiscsi_enable_port(struct beiscsi_hba *phba)
 	/* Re-enable UER. If different TPE occurs then it is recoverable. */
 	beiscsi_set_uer_feature(phba);
 
-	phba->shost->max_id = phba->params.cxns_per_ctrl;
+	phba->shost->max_id = phba->params.cxns_per_ctrl - 1;
 	phba->shost->can_queue = phba->params.ios_per_ctrl;
 	ret = beiscsi_init_port(phba);
 	if (ret < 0) {

drivers/scsi/bnx2i/bnx2i_iscsi.c

@@ -791,7 +791,7 @@ struct bnx2i_hba *bnx2i_alloc_hba(struct cnic_dev *cnic)
 		return NULL;
 	shost->dma_boundary = cnic->pcidev->dma_mask;
 	shost->transportt = bnx2i_scsi_xport_template;
-	shost->max_id = ISCSI_MAX_CONNS_PER_HBA;
+	shost->max_id = ISCSI_MAX_CONNS_PER_HBA - 1;
 	shost->max_channel = 0;
 	shost->max_lun = 512;
 	shost->max_cmd_len = 16;

drivers/scsi/cxgbi/libcxgbi.c

@@ -337,7 +337,7 @@ void cxgbi_hbas_remove(struct cxgbi_device *cdev)
 EXPORT_SYMBOL_GPL(cxgbi_hbas_remove);
 
 int cxgbi_hbas_add(struct cxgbi_device *cdev, u64 max_lun,
-		unsigned int max_id, struct scsi_host_template *sht,
+		unsigned int max_conns, struct scsi_host_template *sht,
 		struct scsi_transport_template *stt)
 {
 	struct cxgbi_hba *chba;
@@ -357,7 +357,7 @@ int cxgbi_hbas_add(struct cxgbi_device *cdev, u64 max_lun,
 
 		shost->transportt = stt;
 		shost->max_lun = max_lun;
-		shost->max_id = max_id;
+		shost->max_id = max_conns - 1;
 		shost->max_channel = 0;
 		shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
 

drivers/scsi/qedi/qedi_main.c

@@ -640,7 +640,7 @@ static struct qedi_ctx *qedi_host_alloc(struct pci_dev *pdev)
 		goto exit_setup_shost;
 	}
 
-	shost->max_id = QEDI_MAX_ISCSI_CONNS_PER_HBA;
+	shost->max_id = QEDI_MAX_ISCSI_CONNS_PER_HBA - 1;
 	shost->max_channel = 0;
 	shost->max_lun = ~0;
 	shost->max_cmd_len = 16;