[src/trunk]: src/sys/dev/ic Fix a few nits in gem_detach:

[martin <martin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/92e721f4eaef
branches:  trunk
changeset: 749607:92e721f4eaef
user:      martin <martin%NetBSD.org@localhost>
date:      Fri Dec 04 11:55:01 2009 +0000

description:
Fix a few nits in gem_detach:
Shuffle some bus_dmamem_ operations around, so they actually clean up
in the correct order.
Do not destroy a callout that might be stopped by if_detach later.
When detaching child devices fails, we have passed the point of no return
already, so complete our own cleanup and return the error in the end.
This happens for example when we have been unable to accomodate all phy
devices at attach time (and this is a separate bug).

diffstat:

 sys/dev/ic/gem.c |  23 ++++++++++-------------
 1 files changed, 10 insertions(+), 13 deletions(-)

diffs (78 lines):

diff -r b6d081a8b29e -r 92e721f4eaef sys/dev/ic/gem.c
--- a/sys/dev/ic/gem.c  Fri Dec 04 11:21:07 2009 +0000
+++ b/sys/dev/ic/gem.c  Fri Dec 04 11:55:01 2009 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: gem.c,v 1.85 2009/07/27 18:10:53 dyoung Exp $ */
+/*     $NetBSD: gem.c,v 1.86 2009/12/04 11:55:01 martin Exp $ */
 
 /*
  *
@@ -37,7 +37,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: gem.c,v 1.85 2009/07/27 18:10:53 dyoung Exp $");
+__KERNEL_RCSID(0, "$NetBSD: gem.c,v 1.86 2009/12/04 11:55:01 martin Exp $");
 
 #include "opt_inet.h"
 #include "bpfilter.h"
@@ -150,13 +150,9 @@
 int
 gem_detach(struct gem_softc *sc, int flags)
 {
-       char *nullbuf;
-       int i, rc;
+       int i, rc = 0;
        struct ifnet *ifp = &sc->sc_ethercom.ec_if;
 
-       nullbuf =
-           (char *)sc->sc_control_data + sizeof(struct gem_control_data);
-
        /*
         * Free any resources we've allocated during the attach.
         * Do this in reverse order and fall through.
@@ -177,18 +173,19 @@
 #endif
                evcnt_detach(&sc->sc_ev_intr);
 
-               callout_destroy(&sc->sc_tick_ch);
 #if NRND > 0
                rnd_detach_source(&sc->rnd_source);
 #endif
                ether_ifdetach(ifp);
                if_detach(ifp);
                ifmedia_delete_instance(&sc->sc_mii.mii_media, IFM_INST_ANY);
+
+               callout_destroy(&sc->sc_tick_ch);
+
                /*FALLTHROUGH*/
        case GEM_ATT_MII:
                sc->sc_att_stage = GEM_ATT_MII;
-               if ((rc = config_detach_children(sc->sc_dev, flags)) != 0)
-                       return rc;
+               rc = config_detach_children(sc->sc_dev, flags);
                /*FALLTHROUGH*/
        case GEM_ATT_7:
                for (i = 0; i < GEM_NRXDESC; i++) {
@@ -206,10 +203,10 @@
                bus_dmamap_unload(sc->sc_dmatag, sc->sc_cddmamap);
                /*FALLTHROUGH*/
        case GEM_ATT_5:
-               bus_dmamap_destroy(sc->sc_dmatag, sc->sc_nulldmamap);
+               bus_dmamap_unload(sc->sc_dmatag, sc->sc_nulldmamap);
                /*FALLTHROUGH*/
        case GEM_ATT_4:
-               bus_dmamem_unmap(sc->sc_dmatag, nullbuf, ETHER_MIN_TX);
+               bus_dmamap_destroy(sc->sc_dmatag, sc->sc_nulldmamap);
                /*FALLTHROUGH*/
        case GEM_ATT_3:
                bus_dmamap_destroy(sc->sc_dmatag, sc->sc_cddmamap);
@@ -227,7 +224,7 @@
        case GEM_ATT_BACKEND_0:
                break;
        }
-       return 0;
+       return rc;
 }
 
 static void