On Sun, 2010-05-16 at 15:29 +0200, Christoph Hellwig wrote:
> On Sat, May 15, 2010 at 06:30:52AM -0700, Nicholas A. Bellinger wrote:
> > From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
> >
> > This patch adds a special BlockDriverState->sg check in block.c:find_image_format()
> > after bdrv_file_open() -> block/raw-posix.c:hdev_open() has been called to determine
> > if we are dealing with a Linux host scsi-generic device or not.
> >
> > The patch then returns the BlockDriver * from find_protocol(), skipping the subsequent
> > bdrv_read() and rest of find_image_format().
>
> That's not quite correct as we don't want to expose formats directly.
> Returning
>
> bdrv_find_format("raw");
>
> should fix it for now,
Ahh, that makes more sense.. Attached is updated patch #1:
[PATCH 1/2] [block]: Make find_image_format() return 'raw' BlockDriver for SG_IO devices
> although I really hate having these special
> cases in block.c.
Indeed having BlockDriverState->sg kinda feels kinda like a hack to
begin with, but it appears this is currently QEMU's way of telling block
code to disable internal SCSI CDB emulation for devices.
Best,
--nab
Attachment:
0001--block-Make-find_image_format-return-raw-Block.patch
Description: application/mbox
