[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH XEN v5 09/23] tools: Refactor hypercall calling wrappers into libxencall.
On Wed, 2015-11-11 at 15:31 +0000, Wei Liu wrote: > On Wed, Nov 11, 2015 at 03:08:13PM +0000, Ian Jackson wrote: > > Ian Campbell writes ("[PATCH XEN v5 09/23] tools: Refactor hypercall > > calling wrappers into libxencall."): > > > libxencall will provide a stable API and ABI for calling hypercalls > > > (although those hypercalls themselves may not have a stable API). As > > > well as the hypercall buffer infrastructure needed in order to safely > > > provide pointer arguments to hypercalls. > > ... > > > +/* > > > + * This library allows you to make arbitrary hypercalls (subject to > > > + * sufficient permission for the process and the domain itself). > > > Note > > > + * that while the library interface is stable the hypercalls are > > > + * subject to their own rules. > > > > Something needs to say what the error handling is like. > > > > Do these functions set errno ? > > > > > +/* > > > + * Call hypercalls with varying numbers of arguments. > > > + */ > > > +int xencall0(xencall_handle *xcall, unsigned int op); > > > > Is the return value the raw hypercall return value, or is hypervisor > > do_foo returning -EFOOBAR turned into to -1/errno=EFOOBAR ? > > (Hopefully the answer to this doesn't depend on the hypercall ABI...) > > > > That is -1/errno=E_XEN_FOOBAR across all OSes. > > (I think this stems from Linux ioctl semantics. Then NetBSD etc follow > suit.) I wish it were that simple :-( _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |