Re: [gsoc] Virtio block device driver

[Stéphanie Ouillon <stephanie@xxxxxxxxx>]

Hello,

I was actually using an older code. Now I updated my code, and it's 
okay. Thanks for the help.


Stéphanie

Le 02/06/11 06:26, Tim Bisson a écrit :
> On 5/31/11 1:05 PM, Stéphanie Ouillon wrote:
> > Hello,
> >
> > I modified some parts of the code of the virtio block device driver 
> > that has been already ported from NetBSD.
> > The code is available here : github.com/arroway/virtio_DragonFlyBSD
> >
> > The initially ported block device driver is available in the block/ 
> > direectory : it was working on its own.
> > What I did is that I modified it so that it could work with a more 
> > general interface, virtio.c
> Can you clarify what you mean by make it "work with a more general 
> interface, virtio.c"? The block driver as it was, would use virtio.c. 
> For example, virtio_negotiate_features() is in virtio.c and is called 
> from virtio-blk.c
>
> I'm referring to the last code written for the virtio-block:
> http://gitorious.org/virtio-drivers/virtio-drivers/trees/master
>
> > First the virtio module is called, and it detects or not a virtio 
> > device. Then, according to the type of the virtio device ( here, a 
> > block device ), it calls the virtio_blk module.
> >
> > I've got some problems to attach my virtio device with virtio_blk.
> >
> > Here is what I did, as I told my mentor Pratyush  Kshirsagar :
> >
> > Some functions were defined twice : in virtio_blk.c and in virtio.c. 
> > In virtio.c, their prototypes accepted a virtio_softc * structure, 
> > but in virtio_blk.c, they wanted a virtio_blk_softc * structure.
> > Now, I only use the functions in virtio.c ( I deleted the 
> > corresponding functions in virtio_blk.c to keep ony the functions 
> > that were specific to the block device ).
> >
> >  So I changed the definition of virtio_blk_softc * structure in 
> > virtio_blk.c. Now it looks like this :
> > (like in the netbsd code)
> >
> > *struct virtio_blk_softc {*
> >
> >     device_t sc_dev;
> >
> > *struct virtio_softc *sc_virtio;*
> >     struct virtqueue sc_vq[1];
> >
> >     struct virtio_blk_req    *sc_reqs;
> >     int sc_readonly;
> >     uint32_t    sc_features;
> >     int     maxxfersize;
> >
> > /    //added : what for ?/
> >     bus_dma_segment_t    sc_reqs_segs[1];
> > /    //I don't use it at the moment ( virtio_blk_attach() )/
> > /    kmutex_t    sc_lock;/
> >
> > /// Block stuff : for testing/ /with /devstat
> >     cdev_t cdev;
> >     struct devstat stats;
> >     struct disk disk;
> >
> > *};*
>
> I think you might be using an older version of the virtio block code? 
> In the gitorious tree I pointed to earlier, there is a pointer to 
> virtio_softc in virtio_blk_softc.
>
> Thanks,
> Tim