Re: [Qemu-devel] Re: [PATCH v2 2/4] Clean-up a little bit the RW related bits of BDRV_O_FLAGS. BDRV_O_RDONLY gone (and so is BDRV_O_ACCESS). Default value for bdrv_flags (0/zero) is READ-ONLY. Need to explicitly request READ-WRITE.

[Markus Armbruster]

"Michael S. Tsirkin" <address@hidden> writes:

> On Wed, Jan 20, 2010 at 08:26:56AM +0100, Markus Armbruster wrote:
>> Jamie Lokier <address@hidden> writes:
>> 
>> > Michael S. Tsirkin wrote:
>> >> On Mon, Jan 18, 2010 at 11:34:59AM +0100, Markus Armbruster wrote:
>> >> > BDRV_O_RDWR is a flag, just like BDRV_SNAPSHOT.  We don't have
>> >> > BDRV_DONT_SNAPSHOT, either.
>> >> 
>> >> Well, this just mirros the file access macros: we have RDONLY, WRONLY
>> >> and RDRW. I assume this similarity is just historical?
>> >
>> > To avoid confusion, why don't we just call the flag BDRV_O_WRITABLE.
>> > Then it's obvious what clearing that flag means.
>> 
>> Sounds good to me.
>
> Won't it be confused with WRONLY?

I doubt it.  "Writable" implies "write-only" no more than "readable"
implies "read-only".