The way that attaching bs->file worked was a bit unusual in that it was
the only child that would be attached to a node which is not opened yet.
Because of this, the block layer couldn't know yet which permissions the
driver would eventually need.
This patch moves the point where bs->file is attached to the beginning
of the individual .bdrv_open() implementations, so drivers already know
what they are going to do with the child. This is also more consistent
with how driver-specific children work.
For a moment, bdrv_open() gets its own BdrvChild to perform image
probing, but instead of directly assigning this BdrvChild to the BDS, it
becomes a temporary one and the node name is passed as an option to the
drivers, so that they can simply use bdrv_open_child() to create another
reference for their own use.
This duplicated child for (the not opened yet) bs is not the final
state, a follow-up patch will change the image probing code to use a
BlockBackend, which is completely independent of bs.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Given that we have raw-win32.c and raw-posix.c, my initial guess at
raw_bsd.c was that it was for dealing with raw files using code
specific to the BSD operating system (beyond what raw-posix could
do). Not so - this name was chosen back in commit e1c66c6 to
distinguish that it was a BSD licensed file, in contrast to the
then-existing raw.c with an unclear and potentially unusable
license. But since it has been more than three years since the
rewrite, it's time to pick a more useful name for this file to
avoid this type of confusion to future contributors that don't know
the backstory, as none of our other files are named solely by the
license they use.
In reality, this file deals with the raw format, which is useful
with any number of protocols, while raw-{win32,posix} deal with
the file protocol (and in turn, that protocol is not limited to
use with the raw format). So rename raw_bsd to raw-format.c. We
could have also used the shorter name raw.c, except that collides
with the earlier use of that filename for a different license,
and it's better to be safe than risk license pollution.
The next patch will also rename raw-win32.c and raw-posix.c to
further distinguish the difference in roles.
It doesn't hurt that this gets rid of an underscore in the filename,
thereby making tab-completion on 'ra<TAB>' easier (now I don't have
to type the shift key, which slows things down :)
Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Kevin Wolf
Eric Blake