[src/pgoyette-localcount]: src/sys/kern In config_devfree(), free the 'struct...

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

details:   https://anonhg.NetBSD.org/src/rev/70b6763ee842
branches:  pgoyette-localcount
changeset: 852835:70b6763ee842
user:      pgoyette <pgoyette%NetBSD.org@localhost>
date:      Fri Jul 22 02:02:24 2016 +0000

description:
In config_devfree(), free the 'struct localcount'

In device_lookup_private_acquire() we need to ensure that the caller has
access to the device_t so the reference that we're acquiring can later
be device_release()d.  So we must require that the device has non-NULL
private data where the pointer back to the device_t can be stored (ie,
in xxx->sc_dev).

diffstat:

 sys/kern/subr_autoconf.c |  31 +++++++++++++++++++++++--------
 1 files changed, 23 insertions(+), 8 deletions(-)

diffs (71 lines):

diff -r 2e9fea9d7ef2 -r 70b6763ee842 sys/kern/subr_autoconf.c
--- a/sys/kern/subr_autoconf.c  Fri Jul 22 01:50:12 2016 +0000
+++ b/sys/kern/subr_autoconf.c  Fri Jul 22 02:02:24 2016 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_autoconf.c,v 1.246.2.2 2016/07/16 22:06:42 pgoyette Exp $ */
+/* $NetBSD: subr_autoconf.c,v 1.246.2.3 2016/07/22 02:02:24 pgoyette Exp $ */
 
 /*
  * Copyright (c) 1996, 2000 Christopher G. Demetriou
@@ -77,7 +77,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.246.2.2 2016/07/16 22:06:42 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.246.2.3 2016/07/22 02:02:24 pgoyette Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ddb.h"
@@ -1237,8 +1237,10 @@
 {
        int priv = (dev->dv_flags & DVF_PRIV_ALLOC);
 
-       if (dev->dv_localcnt != NULL)
+       if (dev->dv_localcnt != NULL) {
                localcount_fini(dev->dv_localcnt);
+               kmem_free(dev->dv_localcnt, sizeof(*dev->dv_localcnt));
+       }
        if (dev->dv_cfattach->ca_devsize > 0)
                kmem_free(dev->dv_private, dev->dv_cfattach->ca_devsize);
        if (priv)
@@ -2256,7 +2258,7 @@
 }
 
 /*
- * device_lookup_accquire:
+ * device_lookup_acquire:
  *
  *     Look up a device instance for a given driver and
  *     hold a reference to the device.
@@ -2307,14 +2309,27 @@
 /*
  * device_lookup_private_acquire:
  *
- *     Look up the softc and acquire a reference to the device
- *     so it won't disappear.
+ *     Look up the softc and acquire a reference to the device so it
+ *     won't disappear.  Note that the caller must ensure that it is
+ *     capable of calling device_release() at some later point in
+ *     time, thus the returned private data must contain some data
+ *     to locate the original device.  Thus the private data must be
+ *     present, not NULL!  If this cannot be guaranteed, the caller
+ *     should use device_lookup_acquire() in order to retain the
+ *     device_t pointer.
  */
 void *
 device_lookup_private_acquire(cfdriver_t cd, int unit)
 {
-
-       return device_private(device_lookup_acquire(cd, unit));
+       device_t dv;
+       void *p;
+
+       dv = device_lookup_acquire(cd, unit);
+       p = device_private(dv);
+       KASSERTMSG(p != NULL || dv == NULL,
+           "%s: device %s has no private data", __func__, cd->cd_name);
+unit, dv, p); */
+       return p;
 }
 
 /*