On Thu, 21 Mar 2024 12:47:18 +0800, Jason Wang <[email protected]> wrote:
> On Tue, Mar 12, 2024 at 11:36 AM Xuan Zhuo <[email protected]> wrote:
> >
> > This commit structure the indirect desc table.
> > Then we can get the desc num directly when doing unmap.
> >
> > And save the dma info to the struct, then the indirect
> > will not use the dma fields of the desc_extra. The subsequent
> > commits will make the dma fields are optional. But for
> > the indirect case, we must record the dma info.
> >
> > Signed-off-by: Xuan Zhuo <[email protected]>
> > ---
> > drivers/virtio/virtio_ring.c | 66 +++++++++++++++++++++---------------
> > 1 file changed, 38 insertions(+), 28 deletions(-)
> >
> > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> > index 0dfbd17e5a87..22a588bba166 100644
> > --- a/drivers/virtio/virtio_ring.c
> > +++ b/drivers/virtio/virtio_ring.c
> > @@ -72,9 +72,16 @@ struct vring_desc_state_split {
> > struct vring_desc *indir_desc; /* Indirect descriptor, if any. */
> > };
> >
> > +struct vring_packed_desc_indir {
> > + dma_addr_t addr; /* Descriptor Array DMA addr. */
> > + u32 len; /* Descriptor Array length. */
> > + u32 num;
> > + struct vring_packed_desc desc[];
> > +};
> > +
> > struct vring_desc_state_packed {
> > void *data; /* Data for callback. */
> > - struct vring_packed_desc *indir_desc; /* Indirect descriptor, if
> > any. */
> > + struct vring_packed_desc_indir *indir_desc; /* Indirect descriptor,
> > if any. */
>
> Maybe it's better just to have a vring_desc_extra here.
Do you mean replacing vring_packed_desc_indir by vring_desc_extra?
I am ok for that. But vring_desc_extra has two extra items:
u16 flags; /* Descriptor flags. */
u16 next; /* The next desc state in a list. */
vring_packed_desc_indir has "desc". I think that is more convenient.
So, I think vring_packed_desc_indir is appropriate.
Or I missed something.
Thanks.
>
> Thanks
>
