Remove sleep() from invalidate call in ses driver, waiting for daemon

process exit. Instead use CAM's standard reference counting to prevent
periph going away until process won't complete. I think that sleep in
single CAM SWI thread is not a good idea and may lead to deadlocks if
daemon process waits for some command completion. Combined with recent
patch avoiding use of CAM SWI for ATA it just causes panics because of
sleeps prohibited in interrupt thread context.

1 files changed, 8 insertions, 10 deletions

diff --git a/sys/cam/scsi/scsi_enc.c b/sys/cam/scsi/scsi_enc.c
index 03e43bc..b1868a6 100644
--- a/sys/cam/scsi/scsi_enc.c
+++ b/sys/cam/scsi/scsi_enc.c
@@ -136,15 +136,8 @@ enc_oninvalidate(struct cam_periph *periph)
 	 */
 	enc->enc_flags |= ENC_FLAG_SHUTDOWN;
 	if (enc->enc_daemon != NULL) {
-		/* Signal and wait for the ses daemon to terminate. */
+		/* Signal the ses daemon to terminate. */
 		wakeup(enc->enc_daemon);
-		/*
-		 * We're called with the SIM mutex held, but we're dropping
-		 * the update mutex here on sleep.  So we have to manually
-		 * drop the SIM mutex.
-		 */
-		cam_periph_sleep(enc->periph, enc->enc_daemon,
-				 PUSER, "thtrm", 0);
 	}
 	callout_drain(&enc->status_updater);
 
@@ -839,6 +832,7 @@ enc_daemon(void *arg)
 	}
 	enc->enc_daemon = NULL;
 	cam_periph_unlock(enc->periph);
+	cam_periph_release(enc->periph);
 	kproc_exit(0);
 }
 
@@ -849,6 +843,9 @@ enc_kproc_init(enc_softc_t *enc)
 
 	callout_init_mtx(&enc->status_updater, enc->periph->sim->mtx, 0);
 
+	if (cam_periph_acquire(enc->periph) != CAM_REQ_CMP)
+		return (ENXIO);
+
 	result = kproc_create(enc_daemon, enc, &enc->enc_daemon, /*flags*/0,
 			      /*stackpgs*/0, "enc_daemon%d",
 			      enc->periph->unit_number);
@@ -857,7 +854,8 @@ enc_kproc_init(enc_softc_t *enc)
 		cam_periph_lock(enc->periph);
 		enc->enc_vec.poll_status(enc);
 		cam_periph_unlock(enc->periph);
-	}
+	} else
+		cam_periph_release(enc->periph);
 	return (result);
 }
  
@@ -955,7 +953,7 @@ enc_ctor(struct cam_periph *periph, void *arg)
 		err = enc_kproc_init(enc);
 		if (err) {
 			xpt_print(periph->path,
-				  "error %d string enc_daemon\n", err);
+				  "error %d starting enc_daemon\n", err);
 			goto out;
 		}
 	}