[Info-vax] Device Driver Kernel-User Buffer Mapping

[Roger Ivie]

On Wednesday, May 12, 2021 at 9:07:42 AM UTC-7, osuv... at gmail.com wrote:
> > VOID_PQ mapped_addr_base; 
> > uint64 mapped_addr_length; 
> > r0_status = sys$crmpsc_pfn_64( 
> > VA$C_P0, 
> > buf/8192, 
> > (1048576*16) / 8192, 
> > PSL$C_USER, 
> > SEC$M_EXPREG|SEC$M_WRT, 
> > &mapped_addr_base, 
> > &mapped_addr_length 
> > ); 
> > 

peeked at my code while i was at work today (can't read news there, don't have sources here at home). the only things that stand out as obviously different between my codes and yours are 1) yes, va$c_p0 needs to be passed by reference. 2) i included sec$m_pfnmap in the flags; don't recall whether that's necessary, but wouldn't surprise me. 3) i included the
final parameter (which you've omitted here; it's supposed to be optional when sec$m_expreg is set); i passed a zero in that parameter.
-- 
roger ivie
roger.ivie at gmail.com