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author | Yang Zhang <yang.z.zhang@intel.com> | 2015-08-28 09:58:54 +0800 |
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committer | Yang Zhang <yang.z.zhang@intel.com> | 2015-09-01 12:44:00 +0800 |
commit | e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch) | |
tree | 66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/contrib/vm/cow | |
parent | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff) |
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/contrib/vm/cow')
-rwxr-xr-x | qemu/roms/ipxe/contrib/vm/cow | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/contrib/vm/cow b/qemu/roms/ipxe/contrib/vm/cow new file mode 100755 index 000000000..054ffdde9 --- /dev/null +++ b/qemu/roms/ipxe/contrib/vm/cow @@ -0,0 +1,49 @@ +#!/bin/sh + +set -e + +imgloop= +tmpfile= +tmploop= +dmname= +cowlink= + +function cleanup () { + set +e + [ -n "$cowlink" ] && rm $cowlink + [ -n "$dmname" ] && dmsetup remove $dmname + [ -n "$tmploop" ] && losetup -d $tmploop + [ -n "$tmpfile" ] && rm $tmpfile + [ -n "$imgloop" ] && losetup -d $imgloop +} + +trap cleanup EXIT + +imgfile=$1 ; shift +command=$1 ; shift +if [ -z "$imgfile" -o -z "$command" ] ; then + echo Syntax: $0 /path/to/image/file command [args..] + exit 1 +fi + +# Set up image loop device +x=`losetup -f` ; losetup -r $x $imgfile ; imgloop=$x + +# Create temporary file and set up temporary loop device +tmpfile=`mktemp $imgfile.XXXXXXXXXX` +truncate -r $imgfile $tmpfile +x=`losetup -f` ; losetup $x $tmpfile ; tmploop=$x + +# Create snapshot device +imgsize=`blockdev --getsz $imgloop` +x=`basename $imgfile` ; echo 0 $imgsize snapshot $imgloop $tmploop N 16 | \ + dmsetup create $x ; dmname=$x +chown --reference=$imgfile /dev/mapper/$dmname +chmod --reference=$imgfile /dev/mapper/$dmname + +# Create symlink +x=$imgfile.cow ; ln -s /dev/mapper/$dmname $x ; cowlink=$x + +# Wait until killed +echo "Created $cowlink" +$command "$@" $cowlink |