On Mon, 23 Sep 2024, Edgar E. Iglesias wrote:
> From: "Edgar E. Iglesias" <edgar.igles...@amd.com>
>
> Add a way to enable/disable buffered IOREQs for PVH machines
> and disable them for ARM. ARM does not support buffered
> IOREQ's nor the legacy way to map IOREQ info pages.
>
> See the following for more details:
> https://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=2fbd7e609e1803ac5e5c26e22aa8e4b5a6cddbb1
> https://xenbits.xen.org/gitweb/?p=xen.git;a=blob;f=xen/arch/arm/ioreq.c;h=2e829d2e7f3760401b96fa7c930e2015fb1cf463;hb=HEAD#l138
>
> Signed-off-by: Edgar E. Iglesias <edgar.igles...@amd.com>
Reviewed-by: Stefano Stabellini <sstabell...@kernel.org>
> ---
> hw/arm/xen-pvh.c | 3 +++
> hw/i386/xen/xen-pvh.c | 3 +++
> hw/xen/xen-pvh-common.c | 2 +-
> include/hw/xen/xen-pvh-common.h | 3 +++
> 4 files changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/hw/arm/xen-pvh.c b/hw/arm/xen-pvh.c
> index 04cb9855af..28af3910ea 100644
> --- a/hw/arm/xen-pvh.c
> +++ b/hw/arm/xen-pvh.c
> @@ -66,6 +66,9 @@ static void xen_arm_machine_class_init(ObjectClass *oc,
> void *data)
> */
> mc->max_cpus = GUEST_MAX_VCPUS;
>
> + /* Xen/ARM does not use buffered IOREQs. */
> + xpc->handle_bufioreq = HVM_IOREQSRV_BUFIOREQ_OFF;
> +
> /* List of supported features known to work on PVH ARM. */
> xpc->has_tpm = true;
> xpc->has_virtio_mmio = true;
> diff --git a/hw/i386/xen/xen-pvh.c b/hw/i386/xen/xen-pvh.c
> index 45645667e9..f1f02d3311 100644
> --- a/hw/i386/xen/xen-pvh.c
> +++ b/hw/i386/xen/xen-pvh.c
> @@ -89,6 +89,9 @@ static void xen_pvh_machine_class_init(ObjectClass *oc,
> void *data)
> /* We have an implementation specific init to create CPU objects. */
> xpc->init = xen_pvh_init;
>
> + /* Enable buffered IOREQs. */
> + xpc->handle_bufioreq = HVM_IOREQSRV_BUFIOREQ_ATOMIC;
> +
> /*
> * PCI INTX routing.
> *
> diff --git a/hw/xen/xen-pvh-common.c b/hw/xen/xen-pvh-common.c
> index 08641fdcec..76a9b2b945 100644
> --- a/hw/xen/xen-pvh-common.c
> +++ b/hw/xen/xen-pvh-common.c
> @@ -195,7 +195,7 @@ static void xen_pvh_init(MachineState *ms)
>
> xen_pvh_init_ram(s, sysmem);
> xen_register_ioreq(&s->ioreq, ms->smp.max_cpus,
> - HVM_IOREQSRV_BUFIOREQ_ATOMIC,
> + xpc->handle_bufioreq,
> &xen_memory_listener);
>
> if (s->cfg.virtio_mmio_num) {
> diff --git a/include/hw/xen/xen-pvh-common.h b/include/hw/xen/xen-pvh-common.h
> index bc09eea936..5cdd23c2f4 100644
> --- a/include/hw/xen/xen-pvh-common.h
> +++ b/include/hw/xen/xen-pvh-common.h
> @@ -43,6 +43,9 @@ struct XenPVHMachineClass {
> */
> int (*set_pci_link_route)(uint8_t line, uint8_t irq);
>
> + /* Allow implementations to optionally enable buffered ioreqs. */
> + uint8_t handle_bufioreq;
> +
> /*
> * Each implementation can optionally enable features that it
> * supports and are known to work.
> --
> 2.43.0
>
