> -----Original Message-----
> From: Jan Beulich <jbeul...@suse.com>
> Sent: 07 December 2020 12:05
> To: Oleksandr Tyshchenko <olekst...@gmail.com>; Paul Durrant <p...@xen.org>
> Cc: Oleksandr Tyshchenko <oleksandr_tyshche...@epam.com>; Andrew Cooper
> <andrew.coop...@citrix.com>;
> George Dunlap <george.dun...@citrix.com>; Ian Jackson <i...@xenproject.org>;
> Julien Grall
> <jul...@xen.org>; Stefano Stabellini <sstabell...@kernel.org>; Wei Liu
> <w...@xen.org>; Roger Pau Monné
> <roger....@citrix.com>; Julien Grall <julien.gr...@arm.com>;
> xen-devel@lists.xenproject.org
> Subject: Re: [PATCH V3 08/23] xen/ioreq: Move x86's ioreq_server to struct
> domain
>
> On 30.11.2020 11:31, Oleksandr Tyshchenko wrote:
> > From: Oleksandr Tyshchenko <oleksandr_tyshche...@epam.com>
> >
> > The IOREQ is a common feature now and this struct will be used
> > on Arm as is. Move it to common struct domain. This also
> > significantly reduces the layering violation in the common code
> > (*arch.hvm* usage).
> >
> > We don't move ioreq_gfn since it is not used in the common code
> > (the "legacy" mechanism is x86 specific).
> >
> > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshche...@epam.com>
>
> Applicable parts
> Acked-by: Jan Beulich <jbeul...@suse.com>
> yet with a question, but maybe more to Paul than to you:
>
> > --- a/xen/include/asm-x86/hvm/domain.h
> > +++ b/xen/include/asm-x86/hvm/domain.h
> > @@ -63,8 +63,6 @@ struct hvm_pi_ops {
> > void (*vcpu_block)(struct vcpu *);
> > };
> >
> > -#define MAX_NR_IOREQ_SERVERS 8
> > -
> > struct hvm_domain {
> > /* Guest page range used for non-default ioreq servers */
> > struct {
> > @@ -73,12 +71,6 @@ struct hvm_domain {
> > unsigned long legacy_mask; /* indexed by HVM param number */
> > } ioreq_gfn;
> >
> > - /* Lock protects all other values in the sub-struct and the default */
> > - struct {
> > - spinlock_t lock;
> > - struct ioreq_server *server[MAX_NR_IOREQ_SERVERS];
> > - } ioreq_server;
> > -
> > /* Cached CF8 for guest PCI config cycles */
> > uint32_t pci_cf8;
> >
> > --- a/xen/include/xen/sched.h
> > +++ b/xen/include/xen/sched.h
> > @@ -316,6 +316,8 @@ struct sched_unit {
> >
> > struct evtchn_port_ops;
> >
> > +#define MAX_NR_IOREQ_SERVERS 8
> > +
> > struct domain
> > {
> > domid_t domain_id;
> > @@ -523,6 +525,14 @@ struct domain
> > /* Argo interdomain communication support */
> > struct argo_domain *argo;
> > #endif
> > +
> > +#ifdef CONFIG_IOREQ_SERVER
> > + /* Lock protects all other values in the sub-struct and the default */
> > + struct {
> > + spinlock_t lock;
> > + struct ioreq_server *server[MAX_NR_IOREQ_SERVERS];
> > + } ioreq_server;
> > +#endif
>
> The comment gets merely moved, but what "default" does it talk about?
> Is this a stale part which would better be dropped at this occasion?
>
Yes, I think that is a stale part of the comment from the days of the default
ioreq server. It can be dropped.
Paul
> Jan
