From d26daa75b0e155b5bc8c050cc964cd6ef794bd88 Mon Sep 17 00:00:00 2001
From: bluhm <bluhm@openbsd.org>
Date: Mon, 15 Jan 2018 23:58:43 +0000
Subject: [PATCH] Add tests that unmount a file system while it is busy.  On a
 vnd device "cp -r" and "rm -rf" are working in the background while "umount
 -f" or "mount -ur" are executed.  Then "fsck -f" is used to verify that the
 file system is clean. Currently this triggers a bug quite reliably.  After
 the mount point has been changed to read-only, the file system check shows
 that not everything was flushed and synced properly.

---
 regress/sys/kern/mount/Makefile     | 76 +++++++++++++++++++++++------
 regress/sys/kern/mount/disktemplate |  2 +-
 2 files changed, 61 insertions(+), 17 deletions(-)

diff --git a/regress/sys/kern/mount/Makefile b/regress/sys/kern/mount/Makefile
index eb877ef1574..bb5cf66f39c 100644
--- a/regress/sys/kern/mount/Makefile
+++ b/regress/sys/kern/mount/Makefile
@@ -1,19 +1,14 @@
-# $OpenBSD: Makefile,v 1.4 2017/04/12 14:46:31 bluhm Exp $
+# $OpenBSD: Makefile,v 1.5 2018/01/15 23:58:43 bluhm Exp $
 
-# This regress test uses a disk template to create 15 partitions on
-# a vnd device.  All are initialized with a ffs file system.  Then
-# they are mounted nestedly in /mnt, see disktemplate for the tree
-# layout.  The unmount-nested test uses umount -f to unmount /mnt,
-# without -f it does not work.  It is checked that the kernel does
-# the unmount recursively.  There must be no dangling mount points.
-# The whole tests have to be run as root.
+# This regress test uses a vnd device to run mount and unmount.
+# All tests have to be run as root.
 
-CLEANFILES=	diskimage stamp-*
+CLEANFILES=	diskimage *.log
 
 .PHONY: disk mount unconfig clean
 
 disk: unconfig
-	dd if=/dev/zero of=diskimage bs=100k count=16
+	dd if=/dev/null of=diskimage bs=1m seek=1100
 	vnconfig vnd0 diskimage
 	disklabel -wA -T ${.CURDIR}/disktemplate vnd0
 	disklabel vnd0
@@ -26,6 +21,8 @@ disk: unconfig
 mount: disk
 	mkdir -p /mnt/regress-mount
 	mount /dev/vnd0a /mnt/regress-mount
+
+mount-nested: mount
 	mkdir /mnt/regress-mount/b
 	mount /dev/vnd0b /mnt/regress-mount/b
 	f=/mnt/regress-mount; for p in d e f g h i j k l m n o p;\
@@ -34,24 +31,71 @@ mount: disk
 	[ `mount | grep -c '/dev/vnd0. on /mnt/regress-mount\>'` -eq 15 ]
 
 unconfig:
+	@echo '\n======== $@ ========'
 	-umount -f /dev/vnd0a 2>/dev/null || true
 	-rmdir /mnt/regress-mount 2>/dev/null || true
 	-vnconfig -u vnd0 2>/dev/null || true
-	-rm -f stamp-setup
 
-stamp-setup:
-	@echo '\n======== $@ ========'
-	${.MAKE} -C ${.CURDIR} mount
-	date >$@
+# The unmount-nested test uses a disk template to create 15 partitions
+# on a vnd device.  All are initialized with a ffs file system.
+# Then they are mounted nestedly in /mnt, see disktemplate for the
+# tree layout.  The unmount-nested test uses umount -f to unmount
+# /mnt, without -f it does not work.  It is checked that the kernel
+# does the unmount recursively.  There must be no dangling mount
+# points.
 
 REGRESS_TARGETS+=	run-regress-unmount-nested
-run-regress-unmount-nested: stamp-setup
+run-regress-unmount-nested: mount-nested
 	@echo '\n======== $@ ========'
 	! umount /mnt/regress-mount
 	umount -f /mnt/regress-mount
 	mount
 	[ `mount | grep -c '/dev/vnd0. on /mnt/regress-mount\>'` -eq 0 ]
 
+# Create a 1 GB vnd partition and fill the ffs file system it with
+# cp -r.  After 15 seconds clean it with rm -rf.  While this is
+# running, unmount with -f.  Run fsck -f to see that everything is
+# clean.
+
+REGRESS_TARGETS+=	run-regress-unmount-busy
+run-regress-unmount-busy: mount
+	@echo '\n======== $@ ========'
+	cp -r /usr /mnt/regress-mount &
+	sleep 5
+	sync
+	sleep 10
+	rm -rf /mnt/regress-mount/usr &
+	sleep .1
+	umount -f /mnt/regress-mount
+	fsck -f -y /dev/rvnd0a 2>&1 | tee fsck.log
+	! egrep 'yes|FILE SYSTEM WAS MODIFIED|MARKING FILE SYSTEM CLEAN' \
+	    fsck.log
+
+# Create a 1 GB vnd partition and fill the ffs file system it with
+# cp -r.  After 15 seconds clean it with rm -rf.  While this is
+# running, remount read-only with -ur.  Unmount the partition and
+# run fsck -f to see that everything is clean.
+
+REGRESS_TARGETS+=	run-regress-mount-readonly
+run-regress-mount-readonly: mount
+	@echo '\n======== $@ ========'
+	cp -r /usr /mnt/regress-mount &
+	sleep 5
+	sync
+	sleep 10
+	rm -rf /mnt/regress-mount/usr &
+	sleep .1
+	mount -f -ur /mnt/regress-mount
+	# XXX mount -ur should not return before it is done
+	for i in `jot 20`; do \
+	    pgrep -xf 'cp -r /usr' || \
+	    pgrep -xf 'rm -rf /mnt/regress-mount/usr' || \
+	    break; sleep 1; done
+	umount /mnt/regress-mount
+	fsck -f -y /dev/rvnd0a 2>&1 | tee fsck.log
+	! egrep 'yes|FILE SYSTEM WAS MODIFIED|MARKING FILE SYSTEM CLEAN' \
+	    fsck.log
+
 REGRESS_TARGETS+=	run-regress-cleanup
 run-regress-cleanup:
 	@echo '\n======== $@ ========'
diff --git a/regress/sys/kern/mount/disktemplate b/regress/sys/kern/mount/disktemplate
index 9199795373b..eeca0403c52 100644
--- a/regress/sys/kern/mount/disktemplate
+++ b/regress/sys/kern/mount/disktemplate
@@ -1,4 +1,4 @@
-/mnt					100k
+/mnt					1G
 /mnt/b					100k
 /mnt/d					100k
 /mnt/d/e				100k
-- 
2.20.1