Module Name: src
Committed By: mlelstv
Date: Thu Aug 20 23:08:33 UTC 2015
Modified Files:
src/sys/dev/dkwedge: dk.c
Log Message:
when scanning for disklabels, close block device only when this was
the first open. The device driver doesn't do reference counting.
This is still subject to race conditions.
To generate a diff of this commit:
cvs rdiff -u -r1.79 -r1.80 src/sys/dev/dkwedge/dk.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/dkwedge/dk.c
diff -u src/sys/dev/dkwedge/dk.c:1.79 src/sys/dev/dkwedge/dk.c:1.80
--- src/sys/dev/dkwedge/dk.c:1.79 Fri Jan 2 01:14:22 2015
+++ src/sys/dev/dkwedge/dk.c Thu Aug 20 23:08:33 2015
@@ -1,4 +1,4 @@
-/* $NetBSD: dk.c,v 1.79 2015/01/02 01:14:22 christos Exp $ */
+/* $NetBSD: dk.c,v 1.80 2015/08/20 23:08:33 mlelstv Exp $ */
/*-
* Copyright (c) 2004, 2005, 2006, 2007 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.79 2015/01/02 01:14:22 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.80 2015/08/20 23:08:33 mlelstv Exp $");
#ifdef _KERNEL_OPT
#include "opt_dkwedge.h"
@@ -944,7 +944,7 @@ dkwedge_read(struct disk *pdk, struct vn
void *tbuf, size_t len)
{
buf_t *bp;
- int error;
+ int error, isopen;
/*
* The kernel cannot read from a character device vnode
@@ -964,6 +964,12 @@ dkwedge_read(struct disk *pdk, struct vn
bp->b_cylinder = 0;
bp->b_error = 0;
+ /*
+ * XXX Only the last user of a block device can close it.
+ * There is no reference counting in the driver.
+ */
+ isopen = pdk->dk_bopenmask & (1 << DISKPART(bp->b_dev));
+
error = bdev_open(bp->b_dev, FREAD, S_IFBLK, curlwp);
if (error)
return error;
@@ -972,7 +978,8 @@ dkwedge_read(struct disk *pdk, struct vn
error = biowait(bp);
putiobuf(bp);
- bdev_close(bp->b_dev, FREAD, S_IFBLK, curlwp);
+ if (!isopen)
+ bdev_close(bp->b_dev, FREAD, S_IFBLK, curlwp);
return error;
}
