[PATCH] XZ compressed memory disk

[Szymon Janc]

Hello,

Attached patches add support for XZ compressed memory disk.
01_xzmisc.diff moves some code from xzio to xzembed to reuse it in xzmemdisk
02_xzmemdisk.diff adds new module xzmemdisk.mod and new option for grub-mkimage 

xzmemdisk.mod depends on gcry_crc.mod and crypto.mod (~22KiB)

To compress memdisk please use following command:
xz --lzma2=dict=2MiB --check=crc32 memdisk.tar
You can adjust dictionary size if needed (dictionary larger than memdisk.tar 
does not improve compression ratio).

I've noticed that on i386 memdisk.tar gets better compresion ratio without BCJ 
filter.

Example (all GRUB modules in tar) size profit:  1296 KiB vs 392 KiB.

Comments and testing(!) are welcome :)

-- 
Szymon K. Janc
address@hidden // GG: 1383435

01_xzmisc.diff
Description: Text Data

02_xzmemdisk.diff
Description: Text Data