[PATCH v11 1/3] xencommons: move module list into a generic place

["Luis R. Rodriguez" <mcgrof@do-not-panic.com>]

From: "Luis R. Rodriguez" <mcgrof@suse.com>

This will allow us to share the same module list with
systemd, and lets us upkeep it in one place. Document this
while at it on the top level README and expand on the wiki:

http://wiki.xen.org/wiki/Category:Host_Configuration#Kernel_modules

In order to upkeep parallelism builds be explicit about the
requirement to complete all actions before any installation
targets.

Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
---
 README                                             | 12 ++++++++
 config/Linux.modules                               | 20 ++++++++++++
 tools/hotplug/Linux/Makefile                       | 14 ++++++---
 .../Linux/init.d/{xencommons => xencommons.in}     | 16 +---------
 tools/hotplug/Linux/update-modules.sh              | 36 ++++++++++++++++++++++
 5 files changed, 79 insertions(+), 19 deletions(-)
 create mode 100644 config/Linux.modules
 rename tools/hotplug/Linux/init.d/{xencommons => xencommons.in} (89%)
 create mode 100755 tools/hotplug/Linux/update-modules.sh

diff --git a/README b/README
index 9bbe734..0c8c7aa 100644
--- a/README
+++ b/README
@@ -183,3 +183,15 @@ There are optional targets as part of Xen's top-level makefile that will
 download and build tboot: install-tboot, build-tboot, dist-tboot, clean-tboot.
 These will download the latest tar file from the SourceForge site using wget,
 then build/install/dist according to Xen's settings.
+
+Required Kernel modules
+======================
+
+Xen has a set of Kernel modules which the init scripts ensure to load before
+before starting Xen guests. The list of modules are maintained in one place:
+
+  * config/$(XEN_OS).modules
+
+For more details refer to:
+
+http://wiki.xen.org/wiki/Category:Host_Configuration#Kernel_modules
diff --git a/config/Linux.modules b/config/Linux.modules
new file mode 100644
index 0000000..8a764df
--- /dev/null
+++ b/config/Linux.modules
@@ -0,0 +1,20 @@
+# The file supports a simple language, comments are ignored, and if you there
+# are module replacements this can be listed by using a pipe to show preference
+# for the first module, followed by the older module.
+
+xen-evtchn
+xen-gntdev
+xen-gntalloc
+xen-blkback
+xen-netback
+xen-pciback
+evtchn
+gntdev
+netbk
+blkbk
+xen-scsibk
+usbbk
+pciback
+xen-acpi-processor
+# Prefer to load blktap2 if found, otherwise load blktap
+blktap2|blktap
diff --git a/tools/hotplug/Linux/Makefile b/tools/hotplug/Linux/Makefile
index d5de9e6..3d2d344 100644
--- a/tools/hotplug/Linux/Makefile
+++ b/tools/hotplug/Linux/Makefile
@@ -33,17 +33,23 @@ UDEV_RULES_DIR = $(CONFIG_DIR)/udev
 UDEV_RULES = xen-backend.rules $(UDEV_RULES-y)
 
 .PHONY: all
-all:
+all: $(XENCOMMONS_INITD)
+
+$(XENCOMMONS_INITD): $(XEN_ROOT)/config/$(XEN_OS).modules $(XENCOMMONS_INITD).in
+	$(XEN_ROOT)/tools/hotplug/Linux/update-modules.sh \
+		$(XEN_ROOT) \
+		$(XEN_OS) \
+		$(XENCOMMONS_INITD) > $@
 
 .PHONY: build
-build:
+build: all
 
 .PHONY: install
 install: all install-initd install-scripts install-udev
 
 # See docs/misc/distro_mapping.txt for INITD_DIR location
 .PHONY: install-initd
-install-initd:
+install-initd: all
 	[ -d $(DESTDIR)$(INITD_DIR) ] || $(INSTALL_DIR) $(DESTDIR)$(INITD_DIR)
 	[ -d $(DESTDIR)$(SYSCONFIG_DIR) ] || $(INSTALL_DIR) $(DESTDIR)$(SYSCONFIG_DIR)
 	[ -d $(DESTDIR)$(LIBEXEC) ] || $(INSTALL_DIR) $(DESTDIR)$(LIBEXEC)
@@ -55,7 +61,7 @@ install-initd:
 	$(INSTALL_PROG) init.d/xen-watchdog $(DESTDIR)$(INITD_DIR)
 
 .PHONY: install-scripts
-install-scripts:
+install-scripts: all
 	[ -d $(DESTDIR)$(XEN_SCRIPT_DIR) ] || \
 		$(INSTALL_DIR) $(DESTDIR)$(XEN_SCRIPT_DIR)
 	set -e; for i in $(XEN_SCRIPTS); \
diff --git a/tools/hotplug/Linux/init.d/xencommons b/tools/hotplug/Linux/init.d/xencommons.in
similarity index 89%
rename from tools/hotplug/Linux/init.d/xencommons
rename to tools/hotplug/Linux/init.d/xencommons.in
index 4ebd636..3939bcc 100644
--- a/tools/hotplug/Linux/init.d/xencommons
+++ b/tools/hotplug/Linux/init.d/xencommons.in
@@ -57,21 +57,7 @@ do_start () {
         local time=0
 	local timeout=30
 
-	modprobe xen-evtchn 2>/dev/null
-	modprobe xen-gntdev 2>/dev/null
-	modprobe xen-gntalloc 2>/dev/null
-	modprobe xen-blkback 2>/dev/null
-	modprobe xen-netback 2>/dev/null
-	modprobe xen-pciback 2>/dev/null
-	modprobe evtchn 2>/dev/null
-	modprobe gntdev 2>/dev/null
-	modprobe netbk 2>/dev/null
-	modprobe blkbk 2>/dev/null
-	modprobe xen-scsibk 2>/dev/null
-	modprobe usbbk 2>/dev/null
-	modprobe pciback 2>/dev/null
-	modprobe xen-acpi-processor 2>/dev/null
-	modprobe blktap2 2>/dev/null || modprobe blktap 2>/dev/null
+	@LOAD_MODULES@
 	mkdir -p /var/run/xen
 
 	if ! `${BINDIR}/xenstore-read -s / >/dev/null 2>&1`
diff --git a/tools/hotplug/Linux/update-modules.sh b/tools/hotplug/Linux/update-modules.sh
new file mode 100755
index 0000000..692d220
--- /dev/null
+++ b/tools/hotplug/Linux/update-modules.sh
@@ -0,0 +1,36 @@
+#!/usr/bin/env bash
+
+set -e
+
+IFS=''
+
+XEN_ROOT=$1
+XEN_OS=$2
+XENCOMMONS_INITD=$3
+
+cat  $XEN_ROOT/config/${XEN_OS}.modules	| (
+	while read l ; do
+		if echo $l | egrep -q "^#" ; then
+			continue
+		fi
+		if echo "$l" | egrep -q "\|" ; then
+			m1=${l%%|*}
+			m2=${l#*|}
+			echo "        modprobe $m1 2>/dev/null || modprobe $m2 2>/dev/null"
+		else
+			echo "        modprobe $l 2>/dev/null"
+		fi
+	done
+) > ${XENCOMMONS_INITD}.modules
+
+cat  ${XENCOMMONS_INITD}.in	| (
+	while read l ; do
+		if echo "$l" | egrep -q "@LOAD_MODULES@" ; then
+			cat ${XENCOMMONS_INITD}.modules
+		else
+			echo $l
+		fi
+	done
+)
+
+rm -f ${XENCOMMONS_INITD}.modules
-- 
2.0.1