[SCSI] iscsi_tcp: Enable any size command

Let through upto the largest command of 260 defined by the scsi standard.
iscsi core supports this already. Now that the scsi-ml supports it we can
start using large commands.

[jejb:rejections fixed up]
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Acked-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

drivers/scsi/iscsi_tcp.c

@@ -1864,7 +1864,7 @@ iscsi_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
 	shost->max_lun = iscsi_max_lun;
 	shost->max_id = 0;
 	shost->max_channel = 0;
-	shost->max_cmd_len = 16;
+	shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
 	shost->can_queue = cmds_max;
 
 	if (iscsi_host_add(shost, NULL))

include/scsi/iscsi_proto.h

@@ -22,6 +22,7 @@
 #define ISCSI_PROTO_H
 
 #include <linux/types.h>
+#include <scsi/scsi.h>
 
 #define ISCSI_DRAFT20_VERSION	0x00
 
@@ -156,7 +157,7 @@ struct iscsi_ecdb_ahdr {
 	uint8_t ahstype;
 	uint8_t reserved;
 	/* 4-byte aligned extended CDB spillover */
-	uint8_t ecdb[260 - ISCSI_CDB_SIZE];
+	uint8_t ecdb[SCSI_MAX_VARLEN_CDB_SIZE - ISCSI_CDB_SIZE];
 };
 
 /* SCSI Response Header */