CVS commit: [prg-localcount2] src/sys/dev

[Paul Goyette]

Module Name:    src
Committed By:   pgoyette
Date:           Thu Apr 27 11:58:58 UTC 2017

Modified Files:
        src/sys/dev [prg-localcount2]: cgd.c

Log Message:
Fix checking of failure-to-spawn a unit (check the returned address for
NULL, vs the pointer to that address).

Ensure that that device_release() is called in all exit paths from cgd_close().

Update handling of CGDIOCCLR ioctl the same as CGDIOCSET.  In particular,
don't return without calling device_release(), as any subsequent attempt to
detach the device will hang forever waiting for its localcount to drain.


To generate a diff of this commit:
cvs rdiff -u -r1.114.4.1 -r1.114.4.2 src/sys/dev/cgd.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/sys/dev/cgd.c
diff -u src/sys/dev/cgd.c:1.114.4.1 src/sys/dev/cgd.c:1.114.4.2
--- src/sys/dev/cgd.c:1.114.4.1	Thu Apr 27 05:36:35 2017
+++ src/sys/dev/cgd.c	Thu Apr 27 11:58:58 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: cgd.c,v 1.114.4.1 2017/04/27 05:36:35 pgoyette Exp $ */
+/* $NetBSD: cgd.c,v 1.114.4.2 2017/04/27 11:58:58 pgoyette Exp $ */
 
 /*-
  * Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cgd.c,v 1.114.4.1 2017/04/27 05:36:35 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cgd.c,v 1.114.4.2 2017/04/27 11:58:58 pgoyette Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -388,8 +388,7 @@ cgd_spawn(int unit, device_t *self)
 	if (config_attach_pseudo(cf) == NULL)
 		return NULL;
 
-	*self = device_lookup_acquire(&cgd_cd, unit);
-	if (self == NULL)
+	if ((*self = device_lookup_acquire(&cgd_cd, unit)) == NULL)
 		return NULL;
 	else {
 		/*
@@ -451,8 +450,8 @@ cgdclose(dev_t dev, int flags, int fmt, 
 			    "unable to detach instance\n");
 			return error;
 		}
-	} else
-		device_release(self);
+	}
+	device_release(self);
 	return 0;
 }
 
@@ -788,8 +787,10 @@ cgdioctl(dev_t dev, u_long cmd, void *da
 		break;
 	case CGDIOCCLR:
 		if (DK_BUSY(&cs->sc_dksc, pmask))
-			return EBUSY;
-		return cgd_ioctl_clr(cs, l);
+			error = EBUSY;
+		else
+			error = cgd_ioctl_clr(cs, l);
+		break;
 	case DIOCGCACHE:
 	case DIOCCACHESYNC:
 		if (!DK_ATTACHED(dksc))