Disable 90-zfs.rules for test suite

When running the zconfig.sh, zpios-sanity.sh, and zfault.sh
from the installed packages the 90-zfs.rules can cause failures.
These will occur because the test suite assumes it has full
control over loading/unloading the module stack.  If the stack
gets asynchronously loaded by the udev rule the test suite
will treat it as a failure.  Resolve the issue by disabling
the offending rule during the tests and enabling it on exit.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

scripts/common.sh.in

@@ -36,6 +36,9 @@ libexecdir=@libexecdir@
 pkglibexecdir=${libexecdir}/@PACKAGE@
 bindir=@bindir@
 sbindir=@sbindir@
+udevdir=@udevdir@
+udevruledir=@udevruledir@
+sysconfdir=@sysconfdir@
 
 ETCDIR=${ETCDIR:-/etc}
 DEVDIR=${DEVDIR:-/dev/disk/zpool}
@@ -113,6 +116,19 @@ skip() {
 	echo -e "${COLOR_BROWN}Skip${COLOR_RESET}"
 }
 
+init() {
+	# Disable the udev rule 90-zfs.rules to prevent the zfs module
+	# stack from being loaded due to the detection of a zfs device.
+	# This is important because the test scripts require full control
+	# over when and how the modules are loaded/unloaded.  A trap is
+	# set to ensure the udev rule is correctly replaced on exit.
+	local RULE=${udevruledir}/90-zfs.rules
+	if test -e  ${RULE}; then
+		trap "mv ${RULE}.disabled ${RULE}; exit $?" INT TERM EXIT
+		mv ${RULE} ${RULE}.disabled
+	fi
+}
+
 spl_dump_log() {
 	${SYSCTL} -w kernel.spl.debug.dump=1 &>/dev/null
 	local NAME=`dmesg | tail -n 1 | cut -f5 -d' '`

scripts/zconfig.sh

@@ -60,6 +60,9 @@ if [ $(id -u) != 0 ]; then
 	die "Must run as root"
 fi
 
+# Initialize the test suite
+init
+
 # Perform pre-cleanup is requested
 if [ ${CLEANUP} ]; then
 	${ZFS_SH} -u

scripts/zfault.sh

@@ -86,6 +86,9 @@ if [ $(id -u) != 0 ]; then
 	die "Must run as root"
 fi
 
+# Initialize the test suite
+init
+
 # Perform pre-cleanup is requested
 if [ ${CLEANUP} ]; then
 	${ZFS_SH} -u

scripts/zpios-sanity.sh

@@ -62,6 +62,9 @@ if [ $(id -u) != 0 ]; then
 	die "Must run as root"
 fi
 
+# Initialize the test suite
+init
+
 # Perform pre-cleanup is requested
 if [ ${CLEANUP} ]; then
 	${ZFS_SH} -u