Re: [Qemu-devel] [PATCH 1/2 v2][UPDATE] Add "cache" parameter to "-drive"

[Fabrice Bellard]

Laurent Vivier wrote:
> This patch adds a new parameter to "-drive"
> 
> Using "cache=off" with "-drive" will open the disk image file using
> "O_DIRECT".
> 
> By default, "cache" is set to "on" to keep original behavior of qemu.
> 
> example:
> 
> "-drive file=my_disk.qcow2,cache=off"
> ---
>  block-raw-posix.c |    8 ++++++++
>  block-raw-win32.c |    4 ++++
>  block.c           |    2 +-
>  block.h           |    1 +
>  hw/fdc.c          |    7 ++++++-
>  hw/ide.c          |   18 ++++++++++++++----
>  hw/scsi-disk.c    |    3 ++-
>  hw/sd.c           |   11 ++++++++++-
>  osdep.c           |   20 ++++++++++++++++++++
>  osdep.h           |    1 +
>  vl.c              |   28 ++++++++++++++++++++++++----
>  11 files changed, 91 insertions(+), 12 deletions(-)
> [...]

I suggest trying to remove the malloc/free which are done at every
blk_read/write for sd.c.

Fabrice.