* Improved initramfs hook; now does not rely on initramfs to provide RAID

    assembly:
    - if a checked mdadm.conf file is present, use that.
    - if an unchecked mdadm.conf is present, create a temporary one
      - if that fails, use the unchecked one iff it contains at least one
        ARRAY statement. Otherwise rely on auto-generation from the initramfs
        during the book (and hope for the best).
    - if no mdadm.conf is found, create one on the fly
      - if that fails, hope that the auto-generation will work during boot
  * Improved the messages printed by the initramfs script.
  * Do not store the debconf answer for whether arrays not listed in the
    configuration file should be used.
  * Now asks again for the devices to start (preseeded with 'all') if the user
    does not want to proceed with devices not listed in the configuration
    file.

2 files changed, 117 insertions, 66 deletions

diff --git a/debian/initramfs/hook b/debian/initramfs/hook
index 6f199de1..dee88b3b 100644
--- a/debian/initramfs/hook
+++ b/debian/initramfs/hook
@@ -43,78 +43,123 @@ MDADM=$(command -v mdadm 2>/dev/null) || :
 [ -r /usr/share/initramfs-tools/hook-functions ] || exit 0
 . /usr/share/initramfs-tools/hook-functions
 
+# copy the binary as early as possible
+copy_exec $MDADM /sbin
+
+# copy all modules into the initramfs, just for safety.
+# we copy raid456 / raid5+raid6 because the hook script just won't do
+# anything when the module cannot be found.
+modules="linear multipath raid0 raid1 raid456 raid5 raid6 raid10"
+for mod in $modules; do manual_add_modules $mod; done
+
+# read in the configuration
 CONFIG=/etc/mdadm/mdadm.conf
 ALTCONFIG=/etc/mdadm.conf
+[ ! -f $CONFIG ] && [ -f $ALTCONFIG ] && CONFIG=$ALTCONFIG || :
+
+DEBIANCONFIG=/etc/default/mdadm
+INITRDSTART=all
+[ -s $DEBIANCONFIG ] && . $DEBIANCONFIG
+[ -z "$INITRDSTART" ] && INITRDSTART=none
 
-[ ! -f $CONFIG ] && [ -f $ALTCONFIG ] && CONFIG=$ALTCONFIG
+DESTMDADMCONF=$DESTDIR/etc/mdadm/mdadm.conf
+DESTCONFIG=$DESTDIR/conf/md.conf
+
+# save the homehost for now, even if we don't use it yet
 if [ -f $CONFIG ]; then
-  if [ -e /var/lib/mdadm/CONF-UNCHECKED ]; then
-    # the file comes from an old installation and hence is not guaranteed to
-    # work. We thus refuse to work.
+  homehost="$(sed -ne 's,^[[:space:]]*HOMEHOST[[:space:]]*,,p' $CONFIG)"
+fi
+if [ -z "${homehost:-}" ] || [ "${homehost:-}" = '<system>' ]; then
+  homehost="$(hostname)"
+fi
+echo "MD_HOMEHOST='$homehost'" > $DESTCONFIG
 
-    echo "E: mdadm: unchecked mdadm.conf file found." >&2
-    echo "I: mdadm: please read /usr/share/doc/mdadm/README.upgrading-2.5.3.gz ." >&2
-    echo "I: mdadm: leaving RAID initialisation to initramfs (mdrun) for now." >&2
-    exit 0
-  fi
+install_config()
+{
+  # install the configuration file
+  mkdir -p ${2%/*}
+  # only copy ARRAY and DEVICE lines, and merge continuation lines into one
+  sed -e :a -re '$!N;s/\n[[:space:]]+/ /;ta' -ne '/^(ARRAY|DEVICE)/P;D' $1 > $2
+}
 
-else
+if [ ! -f $CONFIG ]; then
   # there is no configuration file, so let's create one
+  
   if /usr/share/mdadm/mkconf generate $CONFIG; then
+    # all is well
+    install_config $CONFIG $DESTMDADMCONF
     echo "I: mdadm: auto-generated the mdadm.conf configuration file." >&2
   else
-    echo "E: mdadm: failed to autogenerate the mdadm.conf file." >&2
-    echo "I: mdadm: leaving RAID initialisation to initramfs (mdrun) for now." >&2
+    # we failed to auto-generate, so remove the file and let the emergency
+    # procedure take over
     rm -f $CONFIG
-    exit 0
+    echo "W: mdadm: failed to auto-generate the mdadm.conf file." >&2
+    echo "W: mdadm: please read /usr/share/doc/mdadm/README.upgrading-2.5.3.gz ." >&2
   fi
-fi
+  
+else 
+  
+  if [ -e /var/lib/mdadm/CONF-UNCHECKED ]; then
+    # the file comes from an old installation and hence is not guaranteed to
+    # work. We thus better create one and start all arrays to be sure.
+
+    echo "W: mdadm: unchecked configuration file: $CONFIG" >&2
+    echo "W: mdadm: please read /usr/share/doc/mdadm/README.upgrading-2.5.3.gz ." >&2
+
+    tmpfile="${DESTMDADMCONF}.tmp"
+    if /usr/share/mdadm/mkconf generate $tmpfile; then
+      # all is well, we now have a temporary configuration file
+      echo "I: mdadm: auto-generated temporary mdadm.conf configuration file." >&2
+      install_config $tmpfile $DESTMDADMCONF
+    else
+      # stuff's really broke, as we failed to generate a temporary file.
+      # let's hope the unchecked file works, provided it contains at least one
+      # ARRAY statement...
+      echo "W: mdadm: failed to auto-generate temporary mdadm.conf file." >&2
+      if grep -q '^ARRAY' $CONFIG; then
+        echo "W: mdadm: using the unchecked file and hoping for the best..." >&2
+        install_config $CONFIG $DESTMDADMCONF
+      else
+        echo "W: mdadm: no ARRAYs defined in unchecked mdadm.conf, cannot use..." >&2
+      fi
+    fi
+    rm -f $tmpfile
 
-# install the configuration file
-mkdir -p $DESTDIR/etc/mdadm
-sed -e :a -re '$!N;s/\n[[:space:]]+/ /;ta' -ne '/^(ARRAY|DEVICE)/P;D' \
-  < $CONFIG > $DESTDIR/etc/mdadm/mdadm.conf
-
-# obtain dev:level pairs from config file, honouring multiline entries
-devpairs="$(
-  while read line; do
-    for atom in $line; do
-      case "$atom" in
-        (/dev*) dev=$atom;;
-        (level=*) level=${atom#level=};;
-        (*) :;;
-      esac
-    done
-    [ -n "${dev:-}" ] && echo -n "${dev}:${level} "
-  done < $DESTDIR/etc/mdadm/mdadm.conf)"
+  else
+    # this is the ideal case
+    install_config $CONFIG $DESTMDADMCONF
+    echo "I: mdadm: using configuration file: $CONFIG" >&2
+  fi
 
-copy_exec $MDADM /sbin
+fi
 
-# copy all modules into the initramfs, just for safety.
-# we copy raid456 / raid5+raid6 because the hook script just won't do
-# anything when the module cannot be found.
-modules="linear multipath raid0 raid1 raid456 raid5 raid6 raid10"
-for mod in $modules; do manual_add_modules $mod; done
+# if at this point, $DESTMDADMCONF does not exist, we must let the initramfs
+# handle stuff.
+if [ ! -f $DESTMDADMCONF ]; then
+  echo "W: mdadm: falling back to emergency procedure in initramfs." >&2
+  exit 0
+else
+  # obtain dev:level pairs from config file, honouring multiline entries
+  devpairs="$(
+    while read line; do
+      for atom in $line; do
+        case "$atom" in
+          (/dev*) dev=$atom;;
+          (level=*) level=${atom#level=};;
+          (*) :;;
+        esac
+      done
+      [ -n "${dev:-}" ] && echo -n "${dev}:${level} "
+    done < $DESTMDADMCONF)"
+fi
 
 uniquify()
 {
   for i in $@; do echo "$i"; done | sort -u
 }
 
-DEBIANCONFIG=/etc/default/mdadm
-INITRDSTART=all
-[ -s $DEBIANCONFIG ] && . $DEBIANCONFIG
-
-# save the homehost for now, even if we don't use it yet
-homehost="$(sed -ne 's,^[[:space:]]*HOMEHOST[[:space:]]*,,p' $CONFIG)"
-if [ -z "$homehost" ] || [ "$homehost" = '<system>' ]; then
-  homehost="$(hostname)"
-fi
-echo "MD_HOMEHOST='$homehost'" > $DESTDIR/conf/md.conf
-
-[ -z "$INITRDSTART" ] && INITRDSTART=none
 if [ "$INITRDSTART" != none ] && [ -n "$devpairs" ]; then
-  echo "MD_DEVPAIRS='${devpairs% }'" >> $DESTDIR/conf/md.conf
+  echo "MD_DEVPAIRS='${devpairs% }'" >> $DESTCONFIG
 
   devs=''; levels=''
   for i in $devpairs; do
@@ -143,11 +188,11 @@ if [ "$INITRDSTART" != none ] && [ -n "$devpairs" ]; then
     break
   done
 
-  echo "MD_LEVELS='$levels'" >> $DESTDIR/conf/md.conf
+  echo "MD_LEVELS='$levels'" >> $DESTCONFIG
   if [ "$INITRDSTART" = all ]; then
-    echo "MD_DEVS=all" >> $DESTDIR/conf/md.conf
+    echo "MD_DEVS=all" >> $DESTCONFIG
   else
-    echo "MD_DEVS='$devs'" >> $DESTDIR/conf/md.conf
+    echo "MD_DEVS='$devs'" >> $DESTCONFIG
   fi
 
   # raid4 is handled by raid5
@@ -158,7 +203,7 @@ if [ "$INITRDSTART" != none ] && [ -n "$devpairs" ]; then
     && modules="$(echo $modules | sed -e 's,raid[456],raid456,g')"
 
   modules="$(uniquify $modules | tr '\n' ' ')"
-  echo "MD_MODULES='${modules% }'" >> $DESTDIR/conf/md.conf
+  echo "MD_MODULES='${modules% }'" >> $DESTCONFIG
 
   if [ "$INITRDSTART" = all ]; then
     echo "I: mdadm: will start all available MD arrays from the initial ramdisk." >&2
@@ -169,7 +214,7 @@ if [ "$INITRDSTART" != none ] && [ -n "$devpairs" ]; then
   fi
 
 else
-  echo "MD_DEVS=none" >> $DESTDIR/conf/md.conf
+  echo "MD_DEVS=none" >> $DESTCONFIG
   echo "I: mdadm: no MD arrays will be started from the initial ramdisk." >&2
 fi
 
diff --git a/debian/initramfs/script.local-top b/debian/initramfs/script.local-top
index eecbed6a..621f617a 100644
--- a/debian/initramfs/script.local-top
+++ b/debian/initramfs/script.local-top
@@ -26,7 +26,7 @@ esac
 . /scripts/functions
 
 if [ -e /scripts/local-top/md ]; then
-  log_failure_msg "old md initialisation script found, getting out of its way..."
+  log_warning_msg "old md initialisation script found, getting out of its way..."
   exit 1
 fi
 
@@ -51,7 +51,7 @@ for module in ${MD_MODULES:-}; do
   if modprobe --syslog "$module"; then
     verbose && log_success_msg "loaded module ${module}."
   else
-    verbose && log_failure_msg "failed to load module ${module}."
+    log_failure_msg "failed to load module ${module}."
   fi
 done
 log_end_msg
@@ -65,36 +65,42 @@ fi
 mkdir --parent /dev/md
 
 CONFIG=/etc/mdadm/mdadm.conf
-# this really should not be needed, but also doesn't hurt.
-[ -e $CONFIG ] || \
+# in case the hook failed to install a configuration file, this is out last
+# attempt... the "emergency procedure"... <drumroll>
+if [ ! -e $CONFIG ]; then
+  log_warning_msg "missing mdadm.conf file, trying to create one..."
+  mkdir -p ${CONFIG%/*}
   $MDADM --examine --scan --config=partitions > $CONFIG
+  if [ -s $CONFIG ]; then
+    verbose && log_success_msg "mdadm.conf created."
+  else
+    verbose && log_failure_msg "could not create mdadm.conf, the boot will likely fail."
+  fi
+  MD_DEVS=all
+fi
 
 if [ "$MD_DEVS" = all ]; then
   
   verbose && log_begin_msg "Assembling all MD arrays"
-  
   extra_args=''
   [ -n "$MD_HOMEHOST" ] && \
     extra_args="--homehost='$MD_HOMEHOST' --auto-update-homehost"
   if $MDADM --assemble --scan --run --auto=yes $extra_args; then
-    verbose && log_success_msg "success"
+    verbose && log_success_msg "assembled all arrays."
   else
-    verbose && log_failure_msg "failed"
+    log_failure_msg "failed to assemble all arrays."
   fi
-
   verbose && log_end_msg
 
 elif [ "$MD_DEVS" != none ]; then
   for dev in $MD_DEVS; do
 
     verbose && log_begin_msg "Assembling MD array $dev"
-
     if $MDADM --assemble --run --auto=yes $dev; then
       verbose && log_success_msg "started $dev"
     else
-      verbose && log_failure_msg "failed to start $dev"
+      log_failure_msg "failed to start $dev"
     fi
-
     verbose && log_end_msg
 
   done