These patches allow to open file using O_DIRECT and bypass the host I/O cache.
The v2 is a new version including comments from Anthony Liguori ("directio"
has been renamed "cache"), from Balazs Attila-Mihaly (for Win32 support,
not tested) and Samuel Thibault (for the generic function qemu_memalign()".
[PATCH 1/2] Add "cache" parameter to "-drive"
Using "cache=off" with "-drive" will open the disk image
file using "O_DIRECT".
[PATCH 2/2] Direct IDE I/O
This patch enhances the "-drive ,cache=off" mode with IDE drive emulation
by removing the buffer used in the IDE emulation.
Laurent
