Lock the AMR driver:

- Introduce the amr_io_lock to control access to command queues, bio queues,
  and the hardware.
- Eliminate the taskqueue and do all completion processing in the ithread.
- Assign a static slot number to each command instead of doing a linear
  search for free slots each time a command is needed.
- Modify the interrupt handler to more closely match what Linux does, for
  safety.

1 files changed, 16 insertions, 0 deletions

diff --git a/sys/dev/amr/amr_cam.c b/sys/dev/amr/amr_cam.c
index 3c7aaf889dec..a342699c6192 100644
--- a/sys/dev/amr/amr_cam.c
+++ b/sys/dev/amr/amr_cam.c
@@ -262,8 +262,10 @@ amr_cam_action(struct cam_sim *sim, union ccb *ccb)
 	    /* save the channel number in the ccb */
 	    csio->ccb_h.sim_priv.entries[0].field = cam_sim_bus(sim);
 
+	    mtx_lock(&sc->amr_io_lock);
 	    amr_enqueue_ccb(sc, ccb);
 	    amr_startio(sc);
+	    mtx_unlock(&sc->amr_io_lock);
 	    return;
 	}
 	break;
@@ -491,7 +493,11 @@ out:
 static void
 amr_cam_poll(struct cam_sim *sim)
 {
+    struct amr_softc	*sc = cam_sim_softc(sim);
+
+    mtx_lock(&sc->amr_io_lock);
     amr_done(cam_sim_softc(sim));
+    mtx_unlock(&sc->amr_io_lock);
 }
 
  /********************************************************************************
@@ -500,6 +506,7 @@ amr_cam_poll(struct cam_sim *sim)
 static void
 amr_cam_complete(struct amr_command *ac)
 {
+    struct amr_softc		*sc = ac->ac_sc;
     struct amr_passthrough      *ap = (struct amr_passthrough *)ac->ac_data;
     struct ccb_scsiio           *csio = (struct ccb_scsiio *)ac->ac_private;
     struct scsi_inquiry_data    *inq = (struct scsi_inquiry_data *)csio->data_ptr;
@@ -552,7 +559,11 @@ amr_cam_complete(struct amr_command *ac)
     free(ap, M_DEVBUF);
     if ((csio->ccb_h.flags & CAM_DIR_MASK) != CAM_DIR_NONE)
 	debug(2, "%*D\n", imin(csio->dxfer_len, 16), csio->data_ptr, " ");
+    mtx_unlock(&sc->amr_io_lock);
+    mtx_lock(&Giant);
     xpt_done((union ccb *)csio);
+    mtx_unlock(&Giant);
+    mtx_lock(&sc->amr_io_lock);
     amr_releasecmd(ac);
 }
 
@@ -563,6 +574,7 @@ amr_cam_complete(struct amr_command *ac)
 static void
 amr_cam_complete_extcdb(struct amr_command *ac)
 {
+    struct amr_softc		*sc = ac->ac_sc;
     struct amr_ext_passthrough      *aep = (struct amr_ext_passthrough *)ac->ac_data;
     struct ccb_scsiio           *csio = (struct ccb_scsiio *)ac->ac_private;
     struct scsi_inquiry_data    *inq = (struct scsi_inquiry_data *)csio->data_ptr;
@@ -615,6 +627,10 @@ amr_cam_complete_extcdb(struct amr_command *ac)
     free(aep, M_DEVBUF);
     if ((csio->ccb_h.flags & CAM_DIR_MASK) != CAM_DIR_NONE)
 	debug(2, "%*D\n", imin(csio->dxfer_len, 16), csio->data_ptr, " ");
+    mtx_unlock(&sc->amr_io_lock);
+    mtx_lock(&Giant);
     xpt_done((union ccb *)csio);
+    mtx_unlock(&Giant);
+    mtx_lock(&sc->amr_io_lock);
     amr_releasecmd(ac);
 }