if a busy sas device is unplugged, the pending io on that device will

never complete.

when we get a detach event from the firmware, we currently deactivate the
device and then request the scsi midlayer attempt to detach the device.
this diff now deactivates the device and then resets the target, forcing
the ioc to complete the pending operations. once the reset has completed
we then request a detach of the kernel device.

this lets me hotplug busy sas disks without leaking scsi_xfers or bufs or
anything.

2 files changed, 105 insertions, 14 deletions

diff --git a/sys/dev/ic/mpi.c b/sys/dev/ic/mpi.c
index 0a16fe2e38f..5366cbc3205 100644
--- a/sys/dev/ic/mpi.c
+++ b/sys/dev/ic/mpi.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mpi.c,v 1.160 2010/09/13 07:11:47 dlg Exp $ */
+/*	$OpenBSD: mpi.c,v 1.161 2010/09/13 07:48:12 dlg Exp $ */
 
 /*
  * Copyright (c) 2005, 2006, 2009 David Gwynne <dlg@openbsd.org>
@@ -137,9 +137,13 @@ int			mpi_scsi_probe_virtual(struct scsi_link *);
 
 int			mpi_eventnotify(struct mpi_softc *);
 void			mpi_eventnotify_done(struct mpi_ccb *);
+void			mpi_eventnotify_free(struct mpi_softc *,
+			    struct mpi_rcb *);
 void			mpi_eventack(void *, void *);
 void			mpi_eventack_done(struct mpi_ccb *);
-void			mpi_evt_sas(struct mpi_softc *, struct mpi_rcb *);
+int			mpi_evt_sas(struct mpi_softc *, struct mpi_rcb *);
+void			mpi_evt_sas_detach(void *, void *);
+void			mpi_evt_sas_detach_done(struct mpi_ccb *);
 void			mpi_evt_fc_rescan(struct mpi_softc *);
 void			mpi_fc_rescan(void *, void *);
 
@@ -260,8 +264,13 @@ mpi_attach(struct mpi_softc *sc)
 	}
 
 	switch (sc->sc_porttype) {
-	case MPI_PORTFACTS_PORTTYPE_FC:
 	case MPI_PORTFACTS_PORTTYPE_SAS:
+		SIMPLEQ_INIT(&sc->sc_evt_scan_queue);
+		mtx_init(&sc->sc_evt_scan_mtx, IPL_BIO);
+		scsi_ioh_set(&sc->sc_evt_scan_handler, &sc->sc_iopool,
+		    mpi_evt_sas_detach, sc);
+		/* FALLTHROUGH */
+	case MPI_PORTFACTS_PORTTYPE_FC:
 		if (mpi_eventnotify(sc) != 0) {
 			printf("%s: unable to enable events\n", DEVNAME(sc));
 			goto free_replies;
@@ -2240,7 +2249,10 @@ mpi_eventnotify_done(struct mpi_ccb *ccb)
 		if (sc->sc_scsibus == NULL)
 			break;
 
-		mpi_evt_sas(sc, rcb);
+		if (mpi_evt_sas(sc, rcb) != 0) {
+			/* reply is freed later on */
+			return;
+		}
 		break;
 
 	case MPI_EVENT_RESCAN:
@@ -2255,16 +2267,24 @@ mpi_eventnotify_done(struct mpi_ccb *ccb)
 		break;
 	}
 
+	mpi_eventnotify_free(sc, rcb);
+}
+
+void
+mpi_eventnotify_free(struct mpi_softc *sc, struct mpi_rcb *rcb)
+{
+	struct mpi_msg_event_reply		*enp = rcb->rcb_reply;
+
 	if (enp->ack_required) {
 		mtx_enter(&sc->sc_evt_ack_mtx);
 		SIMPLEQ_INSERT_TAIL(&sc->sc_evt_ack_queue, rcb, rcb_link);
 		mtx_leave(&sc->sc_evt_ack_mtx);
 		scsi_ioh_add(&sc->sc_evt_ack_handler);
 	} else
-		mpi_push_reply(sc, ccb->ccb_rcb);
+		mpi_push_reply(sc, rcb);
 }
 
-void
+int
 mpi_evt_sas(struct mpi_softc *sc, struct mpi_rcb *rcb)
 {
 	struct mpi_evt_sas_change		*ch;
@@ -2275,7 +2295,7 @@ mpi_evt_sas(struct mpi_softc *sc, struct mpi_rcb *rcb)
 	ch = (struct mpi_evt_sas_change *)data;
 
 	if (ch->bus != 0)
-		return;
+		return (0);
 
 	switch (ch->reason) {
 	case MPI_EVT_SASCH_REASON_ADDED:
@@ -2288,12 +2308,14 @@ mpi_evt_sas(struct mpi_softc *sc, struct mpi_rcb *rcb)
 
 	case MPI_EVT_SASCH_REASON_NOT_RESPONDING:
 		scsi_activate(sc->sc_scsibus, ch->target, -1, DVACT_DEACTIVATE);
-		if (scsi_req_detach(sc->sc_scsibus, ch->target, -1,
-		    DETACH_FORCE) != 0) {
-			printf("%s: unable to request detach of %d\n",
-			    DEVNAME(sc), ch->target);
-		}
-		break;
+
+		mtx_enter(&sc->sc_evt_scan_mtx);
+		SIMPLEQ_INSERT_TAIL(&sc->sc_evt_scan_queue, rcb, rcb_link);
+		mtx_leave(&sc->sc_evt_scan_mtx);
+		scsi_ioh_add(&sc->sc_evt_scan_handler);
+
+		/* we'll handle event ack later on */
+		return (1);
 
 	case MPI_EVT_SASCH_REASON_SMART_DATA:
 	case MPI_EVT_SASCH_REASON_UNSUPPORTED:
@@ -2304,6 +2326,71 @@ mpi_evt_sas(struct mpi_softc *sc, struct mpi_rcb *rcb)
 		    "0x%02x\n", DEVNAME(sc), ch->reason);
 		break;
 	}
+
+	return (0);
+}
+
+void
+mpi_evt_sas_detach(void *cookie, void *io)
+{
+	struct mpi_softc			*sc = cookie;
+	struct mpi_ccb				*ccb = io;
+	struct mpi_rcb				*rcb, *next;
+	struct mpi_msg_event_reply		*enp;
+	struct mpi_evt_sas_change		*ch;
+	struct mpi_msg_scsi_task_request	*str;
+
+	DNPRINTF(MPI_D_EVT, "%s: event sas detach handler\n", DEVNAME(sc));
+
+	mtx_enter(&sc->sc_evt_scan_mtx);
+	rcb = SIMPLEQ_FIRST(&sc->sc_evt_scan_queue);
+	if (rcb != NULL) {
+		next = SIMPLEQ_NEXT(rcb, rcb_link);
+		SIMPLEQ_REMOVE_HEAD(&sc->sc_evt_scan_queue, rcb_link);
+	}
+	mtx_leave(&sc->sc_evt_scan_mtx);
+
+	if (rcb == NULL) {
+		scsi_io_put(&sc->sc_iopool, ccb);
+		return;
+	}
+
+	enp = rcb->rcb_reply;
+	ch = (struct mpi_evt_sas_change *)(enp + 1);
+
+	ccb->ccb_done = mpi_evt_sas_detach_done;
+	str = ccb->ccb_cmd;
+
+	str->target_id = ch->target;
+	str->bus = 0;
+	str->function = MPI_FUNCTION_SCSI_TASK_MGMT;
+
+	str->task_type = MPI_MSG_SCSI_TASK_TYPE_TARGET_RESET;
+
+	str->msg_context = htole32(ccb->ccb_id);
+
+	mpi_eventnotify_free(sc, rcb);
+
+	mpi_start(sc, ccb);
+
+	if (next != NULL)
+		scsi_ioh_add(&sc->sc_evt_scan_handler);
+}
+
+void
+mpi_evt_sas_detach_done(struct mpi_ccb *ccb)
+{
+	struct mpi_softc			*sc = ccb->ccb_sc;
+	struct mpi_msg_scsi_task_reply		*r = ccb->ccb_rcb->rcb_reply;
+
+	if (scsi_req_detach(sc->sc_scsibus, r->target_id, -1,
+	    DETACH_FORCE) != 0) {
+		printf("%s: unable to request detach of %d\n",
+		    DEVNAME(sc), r->target_id);
+	}
+
+	mpi_push_reply(sc, ccb->ccb_rcb);
+	scsi_io_put(&sc->sc_iopool, ccb);
 }
 
 void
diff --git a/sys/dev/ic/mpivar.h b/sys/dev/ic/mpivar.h
index d06f7c70151..911217d1a82 100644
--- a/sys/dev/ic/mpivar.h
+++ b/sys/dev/ic/mpivar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mpivar.h,v 1.34 2010/09/13 06:53:43 dlg Exp $ */
+/*	$OpenBSD: mpivar.h,v 1.35 2010/09/13 07:48:12 dlg Exp $ */
 
 /*
  * Copyright (c) 2005 David Gwynne <dlg@openbsd.org>
@@ -140,6 +140,10 @@ struct mpi_softc {
 	struct mutex		sc_evt_ack_mtx;
 	struct scsi_iohandler	sc_evt_ack_handler;
 
+	struct mpi_rcb_list	sc_evt_scan_queue;
+	struct mutex		sc_evt_scan_mtx;
+	struct scsi_iohandler	sc_evt_scan_handler;
+
 	struct workq_task	sc_evt_rescan;
 	struct mutex		sc_evt_rescan_mtx;
 	u_int			sc_evt_rescan_sem;