Everything should be mounted with discard option to take advantage of block...

Everything should be mounted with discard option to take advantage of block devices which support discard/trim

Makefile.common

@@ -50,13 +50,13 @@ $(PACKAGES):
 	mount -t sysfs /sysfs mnt/sys
 	mount -t tmpfs /tmp mnt/tmp
 	if [ -d mnt/data ] ; then \
-	    mount /dev/$(DISK)4 mnt/data ; \
+	    mount -o discard /dev/$(DISK)4 mnt/data ; \
 	    mount --bind mnt/data/home mnt/home ; \
 	    mount --bind mnt/data/root mnt/root ; \
 	    mount --bind mnt/data/var mnt/var ; \
 	fi
 	mount -t tmpfs /tmp mnt/var/tmp
-	mount /dev/$(SECONDARY)1 mnt/build
+	mount -o discard /dev/$(SECONDARY)1 mnt/build
 	chroot mnt $(MAKE) -C $(current_dir)$(firstword $(subst ., ,$@)) $(word 2, $(subst ., ,$@))
 	umount -l mnt/var/tmp
 	if [ -d mnt/data ] && [[ $$(findmnt -M mnt/data) ]] ; then \

common.xml

@@ -433,10 +433,10 @@ PATH=/bin:/usr/bin:/sbin:/usr/sbin
 SECONDARY="${SECONDARY}"
 export LC_ALL PATH SECONDARY HOSTTYPE
 
-mount -o remount,rw /
+mount -o remount,rw,discard /
 
 mkdir /build
-mount /dev/${SECONDARY}1 /build
+mount -o discard /dev/${SECONDARY}1 /build
 make -C /build/packages/linux boot-${BOARD}
 if [ $? -eq 0 ]; then
     umount /dev/${SECONDARY}1
@@ -535,7 +535,7 @@ WantedBy=rescue.target
 rm /mnt/usr/lib/locale/locale-archive
 chroot mnt localedef -i en_GB -f UTF-8 en_GB.UTF-8
 /bin/umount /dev/${SECONDARY}2
-/bin/mount -o remount,rw /
+/bin/mount -o remount,rw,discard /
 /usr/bin/touch /.success
 /bin/rm -rf /etc/systemd/system/rescue.target.wants
 /bin/rm /lib/systemd/system/mount-fstab.service
@@ -641,10 +641,10 @@ SHUTDOWN_WATCHDOG="${SHUTDOWN_WATCHDOG}"
 RUNTIME_WATCHDOG="${RUNTIME_WATCHDOG}"
 export LC_ALL PATH PROJECT_NAME ID PRETTY_NAME HOSTNAME VERSION BUILD_ID ARTIFACT_NAME DEVICE_TYPE BOARD GCC_CONFIG CONSOLE ROOT_DEVICE DISK SECONDARY SHUTDOWN_WATCHDOG RUNTIME_WATCHDOG HOSTTYPE
 
-mount -o remount,rw /
+mount -o remount,rw,discard /
 
 mkdir /build
-mount /dev/${SECONDARY}1 /build
+mount -o discard /dev/${SECONDARY}1 /build
 make -C /build/packages
 if [ $? -eq 0 ]; then
     umount /dev/${SECONDARY}1
@@ -760,10 +760,10 @@ SHUTDOWN_WATCHDOG="${SHUTDOWN_WATCHDOG}"
 RUNTIME_WATCHDOG="${RUNTIME_WATCHDOG}"
 export LC_ALL PATH PROJECT_NAME ID PRETTY_NAME HOSTNAME COPYRIGHT LICENSE TRANSLATOR VERSION BUILD_ID ARTIFACT_NAME DEVICE_TYPE BOARD GCC_CONFIG CONSOLE ROOT_DEVICE DISK SECONDARY SHUTDOWN_WATCHDOG RUNTIME_WATCHDOG HOSTTYPE
 
-mount -o remount,rw /
+mount -o remount,rw,discard /
 
 mkdir /build
-mount /dev/${SECONDARY}1 /build
+mount -o discard /dev/${SECONDARY}1 /build
 make -C /build/packages
 if [ $? -eq 0 ]; then
     umount /dev/${SECONDARY}1
@@ -879,7 +879,7 @@ WantedBy=rescue.target
 /bin/mv -f /tmp/data.xz /mnt/usr/share/factorydefault/data.xz
 /sbin/fstrim -v /mnt
 /bin/umount /dev/${SECONDARY}2
-/bin/mount -o remount,rw /
+/bin/mount -o remount,rw,discard /
 /usr/bin/touch /.success
 /bin/rm -rf /etc/systemd/system/rescue.target.wants
 /bin/rm /lib/systemd/system/mount-fstab.service