debian/patches/mkconfig_loopback.patch

   1 From 67aeec648cc3b3439d65f331adc5f757de3b1c78 Mon Sep 17 00:00:00 2001
   2 From: Colin Watson <cjwatson@debian.org>
   3 Date: Mon, 13 Jan 2014 12:13:00 +0000
   4 Subject: Handle filesystems loop-mounted on file images
   5
   6 Improve prepare_grub_to_access_device to emit appropriate commands for
   7 such filesystems, and ignore them in Linux grub.d scripts.
   8
   9 This is needed for Ubuntu's Wubi installation method.
  10
  11 This patch isn't inherently Debian/Ubuntu-specific.  losetup and
  12 /proc/mounts are Linux-specific, though, so we might need to refine this
  13 before sending it upstream.  The changes to the Linux grub.d scripts
  14 might be better handled by integrating 10_lupin properly instead.
  15
  16 Patch-Name: mkconfig_loopback.patch
  17 ---
  18  util/grub-mkconfig_lib.in   | 24 ++++++++++++++++++++++++
  19  util/grub.d/10_linux.in     |  5 +++++
  20  util/grub.d/20_linux_xen.in |  5 +++++
  21  3 files changed, 34 insertions(+)
  22
  23 diff --git a/util/grub-mkconfig_lib.in b/util/grub-mkconfig_lib.in
  24 index 3a4684e78..9ee60d5fa 100644
  25 --- a/util/grub-mkconfig_lib.in
  26 +++ b/util/grub-mkconfig_lib.in
  27 @@ -133,6 +133,22 @@ prepare_grub_to_access_device ()
  28      esac
  29    done
  30
  31 +  loop_file=
  32 +  case $1 in
  33 +    /dev/loop/*|/dev/loop[0-9])
  34 +      grub_loop_device="${1#/dev/}"
  35 +      loop_file=`losetup "$1" | sed -e "s/^[^(]*(\([^)]\+\)).*/\1/"`
  36 +      case $loop_file in
  37 +        /dev/*) ;;
  38 +        *)
  39 +          loop_device="$1"
  40 +          shift
  41 +          set -- `"${grub_probe}" --target=device "${loop_file}"` "$@"
  42 +        ;;
  43 +      esac
  44 +    ;;
  45 +  esac
  46 +
  47    # Abstraction modules aren't auto-loaded.
  48    abstraction="`"${grub_probe}" --device $@ --target=abstraction`"
  49    for module in ${abstraction} ; do
  50 @@ -165,6 +181,14 @@ prepare_grub_to_access_device ()
  51      echo "fi"
  52    fi
  53    IFS="$old_ifs"
  54 +
  55 +  if [ "x${loop_file}" != x ]; then
  56 +    loop_mountpoint="$(awk '"'${loop_file}'" ~ "^"$2 && $2 != "/" { print $2 }' /proc/mounts | tail -n1)"
  57 +    if [ "x${loop_mountpoint}" != x ]; then
  58 +      echo "loopback ${grub_loop_device} ${loop_file#$loop_mountpoint}"
  59 +      echo "set root=(${grub_loop_device})"
  60 +    fi
  61 +  fi
  62  }
  63
  64  grub_get_device_id ()
  65 diff --git a/util/grub.d/10_linux.in b/util/grub.d/10_linux.in
  66 index c34d470c9..5ff76f59a 100644
  67 --- a/util/grub.d/10_linux.in
  68 +++ b/util/grub.d/10_linux.in
  69 @@ -40,6 +40,11 @@ fi
  70  case ${GRUB_DEVICE} in
  71    /dev/loop/*|/dev/loop[0-9])
  72      GRUB_DEVICE=`losetup ${GRUB_DEVICE} | sed -e "s/^[^(]*(\([^)]\+\)).*/\1/"`
  73 +    # We can't cope with devices loop-mounted from files here.
  74 +    case ${GRUB_DEVICE} in
  75 +      /dev/*) ;;
  76 +      *) exit 0 ;;
  77 +    esac
  78    ;;
  79  esac
  80
  81 diff --git a/util/grub.d/20_linux_xen.in b/util/grub.d/20_linux_xen.in
  82 index c48af948d..af05bd276 100644
  83 --- a/util/grub.d/20_linux_xen.in
  84 +++ b/util/grub.d/20_linux_xen.in
  85 @@ -40,6 +40,11 @@ fi
  86  case ${GRUB_DEVICE} in
  87    /dev/loop/*|/dev/loop[0-9])
  88      GRUB_DEVICE=`losetup ${GRUB_DEVICE} | sed -e "s/^[^(]*(\([^)]\+\)).*/\1/"`
  89 +    # We can't cope with devices loop-mounted from files here.
  90 +    case ${GRUB_DEVICE} in
  91 +      /dev/*) ;;
  92 +      *) exit 0 ;;
  93 +    esac
  94    ;;
  95  esac
  96