Re: [PATCH] arm/monitor vm-events: Implement guest-request support

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

On Thu, 18 Feb 2016, Corneliu ZUZU wrote:
> diff --git a/MAINTAINERS b/MAINTAINERS
> index cd4da04..768ad32 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -356,6 +356,7 @@ M:	Tamas K Lengyel <tamas@tklengyel.com>
>  S:	Supported
>  F:	xen/common/vm_event.c
>  F:	xen/common/mem_access.c
> +F:	xen/common/hvm/event.c
>  F:	xen/common/monitor.c
>  F:	xen/arch/x86/hvm/event.c
>  F:	xen/arch/x86/monitor.c

This needs an Ack from Tamas or Razvan



> diff --git a/xen/arch/arm/hvm.c b/xen/arch/arm/hvm.c
> index 056db1a..767edd1 100644
> --- a/xen/arch/arm/hvm.c
> +++ b/xen/arch/arm/hvm.c
> @@ -22,6 +22,7 @@
>  #include <xen/errno.h>
>  #include <xen/guest_access.h>
>  #include <xen/sched.h>
> +#include <xen/hvm/event.h>
>  
>  #include <xsm/xsm.h>
>  
> @@ -72,6 +73,13 @@ long do_hvm_op(unsigned long op, XEN_GUEST_HANDLE_PARAM(void) arg)
>          break;
>      }
>  
> +    case HVMOP_guest_request_vm_event:
> +        if ( guest_handle_is_null(arg) )
> +            hvm_event_guest_request();
> +        else
> +            rc = -EINVAL;
> +        break;
> +
>      default:
>      {
>          gdprintk(XENLOG_DEBUG, "HVMOP op=%lu: not implemented\n", op);
> diff --git a/xen/common/Makefile b/xen/common/Makefile
> index 0d76efe..703faa5 100644
> --- a/xen/common/Makefile
> +++ b/xen/common/Makefile
> @@ -67,7 +67,7 @@ obj-$(xenoprof)    += xenoprof.o
>  
>  obj-$(CONFIG_COMPAT) += $(addprefix compat/,domain.o kernel.o memory.o multicall.o tmem_xen.o xlat.o)
>  
> -subdir-$(CONFIG_X86) += hvm
> +subdir-y += hvm
>  
>  subdir-$(coverage) += gcov
>  
> diff --git a/xen/common/hvm/Makefile b/xen/common/hvm/Makefile
> index a464a57..11e109d 100644
> --- a/xen/common/hvm/Makefile
> +++ b/xen/common/hvm/Makefile
> @@ -1 +1,2 @@
> -obj-y += save.o
> +obj-$(CONFIG_X86) += save.o
> +obj-y += event.o
> diff --git a/xen/common/hvm/event.c b/xen/common/hvm/event.c
> new file mode 100644
> index 0000000..28ceadc
> --- /dev/null
> +++ b/xen/common/hvm/event.c
> @@ -0,0 +1,96 @@
> +/*
> + * xen/common/hvm/event.c
> + *
> + * Common hardware virtual machine event abstractions.
> + *
> + * Copyright (c) 2004, Intel Corporation.
> + * Copyright (c) 2005, International Business Machines Corporation.
> + * Copyright (c) 2008, Citrix Systems, Inc.
> + * Copyright (c) 2016, Bitdefender S.R.L.
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
> + * more details.
> + *
> + * You should have received a copy of the GNU General Public License along with
> + * this program; If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <xen/hvm/event.h>
> +#include <xen/vm_event.h>
> +#include <asm/hvm/event.h>
> +#if CONFIG_X86
> +#include <asm/altp2m.h>
> +#endif
> +
> +int hvm_event_traps(struct vcpu *v, uint8_t sync, vm_event_request_t *req)
> +{
> +    int rc;
> +    struct domain *d = v->domain;
> +
> +    rc = vm_event_claim_slot(d, &d->vm_event->monitor);
> +    switch ( rc )
> +    {
> +    case 0:
> +        break;
> +    case -ENOSYS:
> +        /*
> +         * If there was no ring to handle the event, then
> +         * simply continue executing normally.
> +         */
> +        return 1;
> +    default:
> +        return rc;
> +    };
> +
> +    if ( sync )
> +    {
> +        req->flags |= VM_EVENT_FLAG_VCPU_PAUSED;
> +        vm_event_vcpu_pause(v);
> +    }
> +
> +#if CONFIG_X86
> +    if ( altp2m_active(d) )

I would rather

#define altp2m_active(d) (0)

on ARM, removing the two ifdefs in this file.


> +    {
> +        req->flags |= VM_EVENT_FLAG_ALTERNATE_P2M;
> +        req->altp2m_idx = vcpu_altp2m(v).p2midx;
> +    }
> +#endif
> +
> +    arch_hvm_event_fill_regs(req);
> +
> +    vm_event_put_request(d, &d->vm_event->monitor, req);
> +
> +    return 1;
> +}
> +
> +void hvm_event_guest_request(void)
> +{
> +    struct vcpu *curr = current;
> +    struct domain *d = curr->domain;
> +
> +    if ( d->monitor.guest_request_enabled )
> +    {
> +        vm_event_request_t req = {
> +            .reason = VM_EVENT_REASON_GUEST_REQUEST,
> +            .vcpu_id = curr->vcpu_id,
> +        };
> +
> +        hvm_event_traps(curr, d->monitor.guest_request_sync, &req);
> +    }
> +}
> +
> +/*
> + * Local variables:
> + * mode: C
> + * c-file-style: "BSD"
> + * c-basic-offset: 4
> + * tab-width: 4
> + * indent-tabs-mode: nil
> + * End:
> + */