MFp4: Large set of CAM inprovements.

- Unify bus reset/probe sequence. Whenever bus attached at boot or later,
CAM will automatically reset and scan it. It allows to remove duplicate
code from many drivers.
- Any bus, attached before CAM completed it's boot-time initialization,
will equally join to the process, delaying boot if needed.
- New kern.cam.boot_delay loader tunable should help controllers that
are still unable to register their buses in time (such as slow USB/
PCCard/ CardBus devices), by adding one more event to wait on boot.
- To allow synchronization between different CAM levels, concept of
requests priorities was extended. Priorities now split between several
"run levels". Device can be freezed at specified level, allowing higher
priority requests to pass. For example, no payload requests allowed,
until PMP driver enable port. ATA XPT negotiate transfer parameters,
periph driver configure caching and so on.
- Frozen requests are no more counted by request allocation scheduler.
It fixes deadlocks, when frozen low priority payload requests occupying
slots, required by higher levels to manage theit execution.
- Two last changes were holding proper ATA reinitialization and error
recovery implementation. Now it is done: SATA controllers and Port
Multipliers now implement automatic hot-plug and should correctly
recover from timeouts and bus resets.
- Improve SCSI error recovery for devices on buses without automatic sense
reporting, such as ATAPI or USB. For example, it allows CAM to wait, while
CD drive loads disk, instead of immediately return error status.
- Decapitalize diagnostic messages and make them more readable and sensible.
- Teach PMP driver to limit maximum speed on fan-out ports.
- Make boot wait for PMP scan completes, and make rescan more reliable.
- Fix pass driver, to return CCB to user level in case of error.
- Increase number of retries in cd driver, as device may return several UAs.

1 files changed, 5 insertions, 54 deletions

diff --git a/sys/dev/twa/tw_osl_cam.c b/sys/dev/twa/tw_osl_cam.c
index b7a085f19789..1d22920f291b 100644
--- a/sys/dev/twa/tw_osl_cam.c
+++ b/sys/dev/twa/tw_osl_cam.c
@@ -56,7 +56,6 @@
 static TW_VOID	twa_action(struct cam_sim *sim, union ccb *ccb);
 static TW_VOID	twa_poll(struct cam_sim *sim);
 static TW_VOID	twa_timeout(TW_VOID *arg);
-static TW_VOID	twa_bus_scan_cb(struct cam_periph *periph, union ccb *ccb);
 
 static TW_INT32	tw_osli_execute_scsi(struct tw_osli_req_context *req,
 	union ccb *ccb);
@@ -76,7 +75,6 @@ TW_INT32
 tw_osli_cam_attach(struct twa_softc *sc)
 {
 	struct cam_devq		*devq;
-	TW_INT32		error;
 
 	tw_osli_dbg_dprintf(3, sc, "entered");
 
@@ -149,23 +147,8 @@ tw_osli_cam_attach(struct twa_softc *sc)
 		mtx_unlock(sc->sim_lock);
 		return(ENXIO);
 	}
-
-	tw_osli_dbg_dprintf(3, sc, "Calling xpt_setup_ccb");
 	mtx_unlock(sc->sim_lock);
 
-	tw_osli_dbg_dprintf(3, sc, "Calling tw_osli_request_bus_scan");
-	/*
-	 * Request a bus scan, so that CAM gets to know of
-	 * the logical units that we control.
-	 */
-	if ((error = tw_osli_request_bus_scan(sc)))
-		tw_osli_printf(sc, "error = %d",
-			TW_CL_SEVERITY_ERROR_STRING,
-			TW_CL_MESSAGE_SOURCE_FREEBSD_DRIVER,
-			0x2104,
-			"Bus scan request to CAM failed",
-			error);
-	
 	tw_osli_dbg_dprintf(3, sc, "exiting");
 	return(0);
 }
@@ -561,7 +544,6 @@ twa_timeout(TW_VOID *arg)
 TW_INT32
 tw_osli_request_bus_scan(struct twa_softc *sc)
 {
-	struct cam_path	*path;
 	union ccb	*ccb;
 
 	tw_osli_dbg_dprintf(3, sc, "entering");
@@ -569,13 +551,12 @@ tw_osli_request_bus_scan(struct twa_softc *sc)
 	/* If we get here before sc->sim is initialized, return an error. */
 	if (!(sc->sim))
 		return(ENXIO);
-	if ((ccb = malloc(sizeof(union ccb), M_TEMP, M_WAITOK)) == NULL)
+	if ((ccb = xpt_alloc_ccb()) == NULL)
 		return(ENOMEM);
-	bzero(ccb, sizeof(union ccb));
 	mtx_lock(sc->sim_lock);
-	if (xpt_create_path(&path, xpt_periph, cam_sim_path(sc->sim),
-			    CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD) != CAM_REQ_CMP) {
-		free(ccb, M_TEMP);
+	if (xpt_create_path(&ccb->ccb_h.path, xpt_periph, cam_sim_path(sc->sim),
+	    CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD) != CAM_REQ_CMP) {
+		xpt_free_ccb(ccb);
 		mtx_unlock(sc->sim_lock);
 		return(EIO);
 	}
@@ -586,11 +567,7 @@ tw_osli_request_bus_scan(struct twa_softc *sc)
 		sc->state &= ~TW_OSLI_CTLR_STATE_SIMQ_FROZEN;
 	}
 
-	xpt_setup_ccb(&ccb->ccb_h, path, 5);
-	ccb->ccb_h.func_code = XPT_SCAN_BUS;
-	ccb->ccb_h.cbfcnp = twa_bus_scan_cb;
-	ccb->crcn.flags = CAM_FLAG_NONE;
-	xpt_action(ccb);
+	xpt_rescan(ccb);
 	mtx_unlock(sc->sim_lock);
 	return(0);
 }
@@ -598,32 +575,6 @@ tw_osli_request_bus_scan(struct twa_softc *sc)
 
 
 /*
- * Function name:	twa_bus_scan_cb
- * Description:		Callback from CAM on a bus scan request.
- *
- * Input:		periph	-- we don't use this
- *			ccb	-- bus scan request ccb that we sent to CAM
- * Output:		None
- * Return value:	None
- */
-static TW_VOID
-twa_bus_scan_cb(struct cam_periph *periph, union ccb *ccb)
-{
-	tw_osli_dbg_printf(3, "entering");
-
-	if (ccb->ccb_h.status != CAM_REQ_CMP)
-		printf("cam_scan_callback: failure status = %x\n",
-			ccb->ccb_h.status);
-	else
-		tw_osli_dbg_printf(3, "success");
-
-	xpt_free_path(ccb->ccb_h.path);
-	free(ccb, M_TEMP);
-}
-
-
-
-/*
  * Function name:	tw_osli_allow_new_requests
  * Description:		Sets the appropriate status bits in a ccb such that,
  *			when the ccb is completed by a call to xpt_done,