On Thu, 2021-06-03 at 14:05 +1000, Nicholas Piggin wrote:
> Excerpts from Haren Myneni's message of May 21, 2021 7:30 pm:
> > PowerNV uses registers to open/close VAS windows, and getting the
> > paste address. Whereas the hypervisor calls are used on PowerVM.
> >
> > This patch adds the platform specific user space window operations
> > and register with the common VAS user space interface.
>
> Basic idea makes sense. I don't understand this code in detail
> though.
> A couple of things,
>
> > Signed-off-by: Haren Myneni <haren@xxxxxxxxxxxxx>
> > ---
> > arch/powerpc/include/asm/vas.h | 14 +++++-
> > arch/powerpc/platforms/book3s/vas-api.c | 52 ++++++++++++-----
> > ----
> > arch/powerpc/platforms/powernv/vas-window.c | 46
> > +++++++++++++++++-
> > 3 files changed, 89 insertions(+), 23 deletions(-)
> >
> > diff --git a/arch/powerpc/include/asm/vas.h
> > b/arch/powerpc/include/asm/vas.h
> > index 6076adf9ab4f..668303198772 100644
> > --- a/arch/powerpc/include/asm/vas.h
> > +++ b/arch/powerpc/include/asm/vas.h
> > @@ -5,6 +5,7 @@
> >
> > #ifndef _ASM_POWERPC_VAS_H
> > #define _ASM_POWERPC_VAS_H
> > +#include <uapi/asm/vas-api.h>
> >
> > struct vas_window;
> >
> > @@ -48,6 +49,16 @@ enum vas_cop_type {
> > VAS_COP_TYPE_MAX,
> > };
> >
> > +/*
> > + * User space window operations used for powernv and powerVM
> > + */
> > +struct vas_user_win_ops {
> > + struct vas_window * (*open_win)(struct vas_tx_win_open_attr *,
> > + enum vas_cop_type);
> > + u64 (*paste_addr)(void *);
> > + int (*close_win)(void *);
>
> Without looking further into the series, why do these two take void
> *
> when the first returns a vas_window * which appears to be the
> required
> argument to these?
Yes, vas_window * should be passed instead of void * for paste_addr() /
close_win()
>
> > +static struct vas_user_win_ops vops = {
> > + .open_win = vas_user_win_open,
> > + .paste_addr = vas_user_win_paste_addr,
> > + .close_win = vas_user_win_close,
> > +};
>
> const?
>
> Thanks,
> Nick
