add support for I/O statistics so that tape speeds can be observed with

iostat(8)

diff --git a/sys/scsi/st.c b/sys/scsi/st.c
index 34ee769..03312e2 100644 (file)
--- a/sys/scsi/st.c
+++ b/sys/scsi/st.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: st.c,v 1.189 2022/02/27 02:27:55 krw Exp $    */
+/*     $OpenBSD: st.c,v 1.190 2023/04/27 18:21:44 robert Exp $ */
 /*     $NetBSD: st.c,v 1.71 1997/02/21 23:03:49 thorpej Exp $  */
 
 /*
@@ -65,6 +65,7 @@
 #include <sys/buf.h>
 #include <sys/mtio.h>
 #include <sys/device.h>
+#include <sys/disk.h>
 #include <sys/conf.h>
 #include <sys/vnode.h>
 
@@ -157,6 +158,7 @@ const struct st_quirk_inquiry_pattern st_quirk_patterns[] = {
 
 struct st_softc {
        struct device sc_dev;
+       struct disk sc_dk;
 
        int flags;
 #define        ST_INFO_VALID           0x00000001
@@ -295,6 +297,8 @@ stattach(struct device *parent, struct device *self, void *aux)
 
        scsi_xsh_set(&st->sc_xsh, link, ststart);
 
+       st->sc_dk.dk_name = st->sc_dev.dv_xname;
+
        /* Set up the buf queue for this device. */
        bufq_init(&st->sc_bufq, BUFQ_FIFO);
 
@@ -309,6 +313,9 @@ stattach(struct device *parent, struct device *self, void *aux)
         * will be checked again at the first open.
         */
        CLR(link->flags, SDEV_MEDIA_LOADED);
+
+       st->sc_dk.dk_flags = DKF_NOLABELREAD;
+       disk_attach(&st->sc_dev, &st->sc_dk);
 }
 
 int
@@ -343,6 +350,8 @@ stdetach(struct device *self, int flags)
 
        bufq_destroy(&st->sc_bufq);
 
+       disk_detach(&st->sc_dk);
+
        return 0;
 }
 
@@ -365,6 +374,11 @@ stopen(dev_t dev, int flags, int fmt, struct proc *p)
        }
        link = st->sc_link;
 
+       if ((error = disk_lock(&st->sc_dk)) != 0) {
+               device_unref(&st->sc_dev);
+               return error;
+       }
+
        if (ISSET(flags, FWRITE) && ISSET(link->flags, SDEV_READONLY)) {
                error = EACCES;
                goto done;
@@ -420,6 +434,7 @@ stopen(dev_t dev, int flags, int fmt, struct proc *p)
 
 done:
        SC_DEBUG(link, SDEV_DB2, ("open complete\n"));
+       disk_unlock(&st->sc_dk);
        device_unref(&st->sc_dev);
        return error;
 }
@@ -444,6 +459,8 @@ stclose(dev_t dev, int flags, int mode, struct proc *p)
        }
        link = st->sc_link;
 
+       disk_lock_nointr(&st->sc_dk);
+
        SC_DEBUG(link, SDEV_DB1, ("closing\n"));
 
        if (ISSET(st->flags, ST_WRITTEN) && !ISSET(st->flags, ST_FM_WRITTEN))
@@ -466,6 +483,8 @@ stclose(dev_t dev, int flags, int mode, struct proc *p)
        CLR(link->flags, SDEV_OPEN);
        scsi_xsh_del(&st->sc_xsh);
 
+       disk_unlock(&st->sc_dk);
+
 done:
        device_unref(&st->sc_dev);
        return error;
@@ -924,6 +943,9 @@ ststart(struct scsi_xfer *xs)
        xs->cookie = bp;
        xs->bp = bp;
 
+       /* Instrumentation. */
+       disk_busy(&st->sc_dk);
+
        /*
         * go ask the adapter to do all this for us
         */
@@ -939,6 +961,7 @@ ststart(struct scsi_xfer *xs)
 void
 st_buf_done(struct scsi_xfer *xs)
 {
+       struct st_softc *st = xs->sc_link->device_softc;
        struct buf *bp = xs->cookie;
        int error, s;
 
@@ -985,6 +1008,9 @@ st_buf_done(struct scsi_xfer *xs)
                break;
        }
 
+       disk_unbusy(&st->sc_dk, bp->b_bcount - xs->resid, bp->b_blkno,
+               bp->b_flags & B_READ);
+
        s = splbio();
        biodone(bp);
        splx(s);