[SCSI] cxgb3i: added per-task data to track transmit progress

added per-task struct cxgb3i_task_data to track the data transmiting
progress and the state of the pdus to be transmitted.
Signed-off-by: Karen Xie <kxie@chelsio.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

drivers/scsi/cxgb3i/cxgb3i.h

@@ -20,6 +20,7 @@
 #include <linux/list.h>
 #include <linux/netdevice.h>
 #include <linux/scatterlist.h>
+#include <linux/skbuff.h>
 #include <scsi/libiscsi_tcp.h>
 
 /* from cxgb3 LLD */
@@ -113,6 +114,26 @@ struct cxgb3i_endpoint {
 	struct cxgb3i_conn *cconn;
 };
 
+/**
+ * struct cxgb3i_task_data - private iscsi task data
+ *
+ * @nr_frags:	# of coalesced page frags (from scsi sgl)
+ * @frags:	coalesced page frags (from scsi sgl)
+ * @skb:	tx pdu skb
+ * @offset:	data offset for the next pdu
+ * @count:	max. possible pdu payload
+ * @sgoffset:	offset to the first sg entry for a given offset
+ */
+#define MAX_PDU_FRAGS	((ULP2_MAX_PDU_PAYLOAD + 512 - 1) / 512)
+struct cxgb3i_task_data {
+	unsigned short nr_frags;
+	skb_frag_t frags[MAX_PDU_FRAGS];
+	struct sk_buff *skb;
+	unsigned int offset;
+	unsigned int count;
+	unsigned int sgoffset;
+};
+
 int cxgb3i_iscsi_init(void);
 void cxgb3i_iscsi_cleanup(void);
 

drivers/scsi/cxgb3i/cxgb3i_iscsi.c

@@ -364,7 +364,8 @@ cxgb3i_session_create(struct iscsi_endpoint *ep, u16 cmds_max, u16 qdepth,
 
 	cls_session = iscsi_session_setup(&cxgb3i_iscsi_transport, shost,
 					  cmds_max,
-					  sizeof(struct iscsi_tcp_task),
+					  sizeof(struct iscsi_tcp_task) +
+					  sizeof(struct cxgb3i_task_data),
 					  initial_cmdsn, ISCSI_MAX_TARGET);
 	if (!cls_session)
 		return NULL;
@@ -844,7 +845,7 @@ static struct scsi_host_template cxgb3i_host_template = {
 	.proc_name		= "cxgb3i",
 	.queuecommand		= iscsi_queuecommand,
 	.change_queue_depth	= iscsi_change_queue_depth,
-	.can_queue		= 128 * (ISCSI_DEF_XMIT_CMDS_MAX - 1),
+	.can_queue		= CXGB3I_SCSI_QDEPTH_DFLT - 1,
 	.sg_tablesize		= SG_ALL,
 	.max_sectors		= 0xFFFF,
 	.cmd_per_lun		= ISCSI_DEF_CMD_PER_LUN,