[src/riastradh-drm2]: src/sys/external/bsd/drm2/drm Little stab at making drm...

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

details:   https://anonhg.NetBSD.org/src/rev/17707cabe5c8
branches:  riastradh-drm2
changeset: 788474:17707cabe5c8
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Wed Jul 24 03:58:19 2013 +0000

description:
Little stab at making drm_attach fail more gracefully.

diffstat:

 sys/external/bsd/drm2/drm/drm_drv.c |  54 ++++++++++++++++++++++++------------
 1 files changed, 36 insertions(+), 18 deletions(-)

diffs (147 lines):

diff -r a4037582dcd1 -r 17707cabe5c8 sys/external/bsd/drm2/drm/drm_drv.c
--- a/sys/external/bsd/drm2/drm/drm_drv.c       Wed Jul 24 03:58:04 2013 +0000
+++ b/sys/external/bsd/drm2/drm/drm_drv.c       Wed Jul 24 03:58:19 2013 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: drm_drv.c,v 1.1.2.18 2013/07/24 03:56:33 riastradh Exp $       */
+/*     $NetBSD: drm_drv.c,v 1.1.2.19 2013/07/24 03:58:19 riastradh Exp $       */
 
 /*-
  * Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: drm_drv.c,v 1.1.2.18 2013/07/24 03:56:33 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: drm_drv.c,v 1.1.2.19 2013/07/24 03:58:19 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/types.h>
@@ -59,6 +59,7 @@
        struct drm_device       *sc_drm_dev;
        struct drm_minor        sc_minor[__arraycount(drm_minor_types)];
        unsigned int            sc_opencount;
+       bool                    sc_initialized;
 };
 
 struct drm_attach_args {
@@ -71,6 +72,8 @@
 static void    drm_attach(device_t, device_t, void *);
 static int     drm_detach(device_t, int);
 
+static void    drm_undo_fill_in_dev(struct drm_device *);
+
 static struct drm_softc *drm_dev_softc(dev_t);
 static struct drm_minor *drm_dev_minor(dev_t);
 
@@ -266,13 +269,15 @@
 
        aprint_normal("\n");
 
+       sc->sc_initialized = false;     /* paranoia */
+
        dev->driver = daa->daa_driver;
        sc->sc_drm_dev = dev;
        sc->sc_opencount = 0;
 
        if (device_unit(self) >= 64) { /* XXX Need to do something here!  */
                aprint_error_dev(self, "can't handle >=64 drm devices!");
-               return;
+               goto fail0;
        }
 
        for (i = 0; i < __arraycount(drm_minor_types); i++) {
@@ -295,13 +300,9 @@
         */
        error = drm_fill_in_dev(dev, NULL, dev->driver);
        if (error) {
-               /*
-                * XXX This leaves the driver in a state such that
-                * detaching it will fail horribly.  Please fix!
-                */
                aprint_error_dev(parent, "unable to initialize drm: %d\n",
                    error);
-               return;
+               goto fail0;
        }
 
        if (dev->driver->load != NULL) {
@@ -309,13 +310,23 @@
                if (error) {
                        aprint_error_dev(parent, "unable to load driver: %d\n",
                            error);
-                       return;
+                       goto fail1;
                }
        }
 
 #if 0                          /* XXX drm wsdisplay */
        attach wsdisplay;
 #endif
+
+       /* Success!  */
+       sc->sc_initialized = true;
+       return;
+
+fail2: __unused
+       if (dev->driver->unload != NULL)
+               (*dev->driver->unload)(dev);
+fail1: drm_undo_fill_in_dev(dev);
+fail0: return;
 }
 
 static int
@@ -325,18 +336,31 @@
        KASSERT(sc != NULL);
        struct drm_device *const dev = sc->sc_drm_dev;
        KASSERT(dev != NULL);
-       const struct drm_driver *const driver = dev->driver;
-       KASSERT(driver != NULL);
+
+       if (!sc->sc_initialized)
+               return 0;
 
        if (sc->sc_opencount != 0)
                return EBUSY;
 
+       /* XXX The placement of this is pretty random...  */
+       if (dev->driver->unload != NULL)
+               (*dev->driver->unload)(dev);
+
+       drm_undo_fill_in_dev(dev);
+
+       return 0;
+}
+
+static void
+drm_undo_fill_in_dev(struct drm_device *dev)
+{
        /*
         * XXX Synchronize with drm_fill_in_dev, perhaps with reference
         * to drm_put_dev.
         */
 
-       if (ISSET(driver->driver_features, DRIVER_GEM))
+       if (ISSET(dev->driver->driver_features, DRIVER_GEM))
                drm_gem_destroy(dev);
 
        drm_ctxbitmap_cleanup(dev);
@@ -353,10 +377,6 @@
                DRM_DEBUG("mtrr_del=%d\n", error);
        }
 
-       /* XXX The placement of this is pretty random...  */
-       if (dev->driver->unload != NULL)
-               (*dev->driver->unload)(dev);
-
        /* XXX Move into dev->driver->bus->agp_destroy.  */
        if (drm_core_has_AGP(dev) && (dev->agp != NULL)) {
                kfree(dev->agp);
@@ -370,8 +390,6 @@
        linux_mutex_destroy(&dev->struct_mutex);
        spin_lock_destroy(&dev->event_lock);
        spin_lock_destroy(&dev->count_lock);
-
-       return 0;
 }
 
 static struct drm_softc *