Give the SCSI layer the ability to requeue i/o's rejected by a driver

using the new NO_CCB result. Currently a no-op since no driver produces
that result.

ok dlg@ marco@ deraadt@

1 files changed, 41 insertions, 12 deletions

diff --git a/sys/scsi/sd.c b/sys/scsi/sd.c
index d7152397f64..b65b219aead 100644
--- a/sys/scsi/sd.c
+++ b/sys/scsi/sd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sd.c,v 1.114 2006/11/28 16:56:50 dlg Exp $	*/
+/*	$OpenBSD: sd.c,v 1.115 2006/12/12 02:44:36 krw Exp $	*/
 /*	$NetBSD: sd.c,v 1.111 1997/04/02 02:29:41 mycroft Exp $	*/
 
 /*-
@@ -57,7 +57,7 @@
 #include <sys/types.h>
 #include <sys/param.h>
 #include <sys/systm.h>
-#include <sys/kernel.h>
+#include <sys/timeout.h>
 #include <sys/file.h>
 #include <sys/stat.h>
 #include <sys/ioctl.h>
@@ -98,6 +98,7 @@ void	sdminphys(struct buf *);
 void	sdgetdisklabel(dev_t, struct sd_softc *, struct disklabel *,
 			    struct cpu_disklabel *, int);
 void	sdstart(void *);
+void	sdrestart(void *);
 void	sddone(struct scsi_xfer *);
 void	sd_shutdown(void *);
 int	sd_reassign_blocks(struct sd_softc *, u_long);
@@ -209,6 +210,8 @@ sdattach(parent, self, aux)
 	 */
 	printf("\n");
 
+	timeout_set(&sd->sc_timeout, sdrestart, sd);
+
 	/* Spin up the unit ready or not. */
 	scsi_start(sc_link, SSS_START, scsi_autoconf | SCSI_SILENT |
 	    SCSI_IGNORE_ILLEGAL_REQUEST | SCSI_IGNORE_MEDIA_CHANGE);
@@ -495,6 +498,8 @@ sdclose(dev, flag, fmt, p)
 
 			sd->sc_link->flags &= ~SDEV_EJECTING;
 		}
+
+		timeout_del(&sd->sc_timeout);
 	}
 
 	sdunlock(sd);
@@ -601,7 +606,7 @@ done:
  * continues to be drained.
  *
  * must be called at the correct (highish) spl level
- * sdstart() is called at splbio from sdstrategy and scsi_done
+ * sdstart() is called at splbio from sdstrategy, sdrestart and scsi_done
  */
 void
 sdstart(v)
@@ -706,14 +711,6 @@ sdstart(v)
 		disk_busy(&sd->sc_dk);
 
 		/*
-		 * Mark the disk dirty so that the cache will be
-		 * flushed on close.
-		 */
-		if ((bp->b_flags & B_READ) == 0)
-			sd->flags |= SDF_DIRTY;
-
-
-		/*
 		 * Call the routine that chats with the adapter.
 		 * Note: we cannot sleep as we may be an interrupt
 		 */
@@ -721,15 +718,45 @@ sdstart(v)
 		    (u_char *)bp->b_data, bp->b_bcount,
 		    SDRETRIES, 60000, bp, SCSI_NOSLEEP |
 		    ((bp->b_flags & B_READ) ? SCSI_DATA_IN : SCSI_DATA_OUT));
-		if (error) {
+		switch (error) {
+		case 0:
+			/*
+			 * Mark the disk dirty so that the cache will be
+			 * flushed on close.
+			 */
+			if ((bp->b_flags & B_READ) == 0)
+				sd->flags |= SDF_DIRTY;
+			timeout_del(&sd->sc_timeout);
+			break;
+		case EAGAIN:
+			/*
+			 * The device can't start another i/o. Try again later.
+			 */
+			dp->b_actf = bp;
+			disk_unbusy(&sd->sc_dk, 0, 0);
+			timeout_add(&sd->sc_timeout, 1);
+			return;
+		default:
 			disk_unbusy(&sd->sc_dk, 0, 0);
 			printf("%s: not queued, error %d\n",
 			    sd->sc_dev.dv_xname, error);
+			break;
 		}
 	}
 }
 
 void
+sdrestart(v)
+	void *v;
+{
+	int s;
+
+	s = splbio();
+	sdstart(v);
+	splx(s);
+}
+
+void
 sddone(xs)
 	struct scsi_xfer *xs;
 {
@@ -1036,6 +1063,8 @@ sd_shutdown(arg)
 	 */
 	if ((sd->flags & SDF_DIRTY) != 0)
 		sd_flush(sd, SCSI_AUTOCONF);
+
+	timeout_del(&sd->sc_timeout);
 }
 
 /*