scsi: iscsi: Stop using the SCSI pointer

Instead of storing the iSCSI task pointer and the session age in the SCSI
pointer, use command-private variables. This patch prepares for removal of
the SCSI pointer from struct scsi_cmnd.

The list of iSCSI drivers has been obtained as follows:
$ git grep -lw iscsi_host_alloc
drivers/infiniband/ulp/iser/iscsi_iser.c
drivers/scsi/be2iscsi/be_main.c
drivers/scsi/bnx2i/bnx2i_iscsi.c
drivers/scsi/cxgbi/libcxgbi.c
drivers/scsi/iscsi_tcp.c
drivers/scsi/libiscsi.c
drivers/scsi/qedi/qedi_main.c
drivers/scsi/qla4xxx/ql4_os.c
include/scsi/libiscsi.h

Note: it is not clear to me how the qla4xxx driver can work without this
patch since it uses the scsi_cmnd::SCp.ptr member for two different
purposes:
- The qla4xxx driver uses this member to store a struct srb pointer.
- libiscsi uses this member to store a struct iscsi_task pointer.

Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Cc: Chris Leech <cleech@redhat.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Nilesh Javali <njavali@marvell.com>
Cc: Manish Rangankar <mrangankar@marvell.com>
Cc: Karen Xie <kxie@chelsio.com>
Cc: Ketan Mukadam <ketan.mukadam@broadcom.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>

iscsi

Link: https://lore.kernel.org/r/20220218195117.25689-26-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/scsi/qedi/qedi_fw.c b/drivers/scsi/qedi/qedi_fw.c
index 5916ed7662d5..4e99508ff95d 100644
--- a/drivers/scsi/qedi/qedi_fw.c
+++ b/drivers/scsi/qedi/qedi_fw.c
@@ -603,9 +603,9 @@ static void qedi_scsi_completion(struct qedi_ctx *qedi,
 		goto error;
 	}
 
-	if (!sc_cmd->SCp.ptr) {
+	if (!iscsi_cmd(sc_cmd)->task) {
 		QEDI_WARN(&qedi->dbg_ctx,
-			  "SCp.ptr is NULL, returned in another context.\n");
+			  "NULL task pointer, returned in another context.\n");
 		goto error;
 	}