fix luks close timing

backup.sh

@@ -52,8 +52,26 @@ function find_usb() {
     return 1
 }
 
+
+function mount_luks() {
+    for n in `seq 0 9`; do
+        log "       trying to mount /dev/mapper/crypted_usb"
+        waiting=$(grep 'Dirty\|Writeback' /proc/meminfo | grep Writeback: | awk {'print $2'})
+        if [[ wating -eq "0" ]]; then
+            echo $1 | /usr/sbin/cryptsetup luksOpen $2 crypted_usb
+            log "[ OK ] mounted /dev/mapper/crypted_usb"
+            return 0
+        else
+            log "[FAIL] mounted /dev/mapper/crypted_usb"
+        fi
+        sleep 2
+    done
+    echo "R1"
+    return 1
+}
+
 function mount_usb() {
-    echo $LUKS_PASS | /usr/sbin/cryptsetup luksOpen $USB_PARTITION crypted_usb
+    mount_luks $LUKS_PASS $USB_PARTITION 
     if [ $? = 0 ]; then
         log "[ OK ] $USB_PARTITION decrypted"
         /usr/bin/mount /dev/mapper/crypted_usb /mnt/usb
@@ -136,11 +154,24 @@ function check_copy () {
     return 0
 }
 
+function luks_close() {
+    for n in `seq 0 9`; do
+        waiting=$(grep 'Dirty\|Writeback' /proc/meminfo | grep Writeback: | awk {'print $2'})
+        if [[ waiting -eq "0" ]]; then
+            cryptsetup luksClose /dev/mapper/crypted_usb
+            return 0
+        fi  
+        sleep 2
+    done
+    echo "R1"
+    return 1
+}
+
 function umount_usb() {
     if /usr/bin/umount $USB_MOUNT; then
         if [ $? = 0 ]; then
             log "[ OK ] umount usb disk"
-            cryptsetup luksClose /dev/mapper/crypted_usb
+            luks_close
             if [ $? = 0 ]; then
                 log "[ OK ] close disk encryption"
                 return 0