More rototilling with target mode in an attemp to get multiple

CCB at a time outstanding reliable. It's not there yet, but this
is the direction to go in so might as well commit. So far,
multiple at a time CCBs work (see ISP_INTERNAL_TARGET test mode),
but it fails if there are more downstream than the SIM wants
to handle and SRR is sort of confused when this happens, plus
it is not entirely quite clear what one does if a CCB/CTIO fails
and you have more in flight (that don't fail, say) and more queued
up at the SIM level that haven't been started yet.

Some of this is driven because there apparently is no flow control
to requeue XPT_CONTINUE_IO requests like there are for XPT_SCSI_IO
requests. It is also more driven in that the few target mode
periph drivers there are are not really set up for handling pushback-
heck most of them don't even check for errors (and what would they
really do with them anyway? It's the initiator's problem, really....).

The data transfer arithmetic has been worked over again to handle
multiple outstanding commands, so you have a notion of what's been
moved already as well as what's currently in flight. It turns that
this led to uncovering a REPORT_LUNS bug in the ISP_INTERNAL_TARGET
code which was sending back 24 bytes of rpl data instead of the
specified 16. What happened furthermore here is that sending back
16 bytes and reporting an overrun of 8 bytes made the initiator
(running FC-Tape aware f/w) mad enough to request, and keep
requesting, another FCP response (I guess it didn't like the answer
so kept asking for it again).

Sponsored by: Spectralogic
MFC after:	1 month

1 files changed, 13 insertions, 1 deletions

diff --git a/sys/dev/isp/isp_freebsd.h b/sys/dev/isp/isp_freebsd.h
index 5bd1268..130d084 100644
--- a/sys/dev/isp/isp_freebsd.h
+++ b/sys/dev/isp/isp_freebsd.h
@@ -102,7 +102,7 @@ typedef struct {
 	void *		next;
 	uint32_t	orig_datalen;
 	uint32_t	bytes_xfered;
-	uint32_t	last_xframt;
+	uint32_t	bytes_in_transit;
 	uint32_t	tag;		/* typically f/w RX_ID */
 	uint32_t	lun;
 	uint32_t	nphdl;
@@ -112,6 +112,7 @@ typedef struct {
 	uint16_t	oxid;	/* wire oxid */
 	uint16_t	word3;	/* PRLI word3 params */
 	uint16_t	ctcnt;	/* number of CTIOs currently active */
+	uint8_t		seqno;	/* CTIO sequence number */
 	uint32_t
 			srr_notify_rcvd	: 1,
 			cdb0		: 8,
@@ -134,6 +135,14 @@ typedef struct {
 #define	ATPD_STATE_LAST_CTIO		4
 #define	ATPD_STATE_PDON			5
 
+#define	ATPD_CCB_OUTSTANDING		16
+
+#define	ATPD_SEQ_MASK			0x7f
+#define	ATPD_SEQ_NOTIFY_CAM		0x80
+#define	ATPD_SET_SEQNO(hdrp, atp)	((isphdr_t *)hdrp)->rqs_seqno &= ~ATPD_SEQ_MASK, ((isphdr_t *)hdrp)->rqs_seqno |= (atp)->seqno
+#define	ATPD_GET_SEQNO(hdrp)		(((isphdr_t *)hdrp)->rqs_seqno & ATPD_SEQ_MASK)
+#define	ATPD_GET_NCAM(hdrp)		((((isphdr_t *)hdrp)->rqs_seqno & ATPD_SEQ_NOTIFY_CAM) != 0)
+
 typedef union inot_private_data inot_private_data_t;
 union inot_private_data {
 	inot_private_data_t *next;
@@ -149,9 +158,11 @@ typedef struct isp_timed_notify_ack {
 	uint8_t data[64];	 /* sb QENTRY_LEN, but order of definitions is wrong */
 } isp_tna_t;
 
+TAILQ_HEAD(isp_ccbq, ccb_hdr);
 typedef struct tstate {
 	SLIST_ENTRY(tstate) next;
 	struct cam_path *owner;
+	struct isp_ccbq waitq;		/* waiting CCBs */
 	struct ccb_hdr_slist atios;
 	struct ccb_hdr_slist inots;
 	uint32_t hold;
@@ -179,6 +190,7 @@ struct isp_pcmd {
 	bus_dmamap_t 		dmap;		/* dma map for this command */
 	struct ispsoftc *	isp;		/* containing isp */
 	struct callout		wdog;		/* watchdog timer */
+	uint32_t		datalen;	/* data length for this command (target mode only) */
 	uint8_t			totslen;	/* sense length on status response */
 	uint8_t			cumslen;	/* sense length on status response */
 	uint8_t 		crn;		/* command reference number */