Re: [Xen-devel] [PATCH 3 of 6] REDO: mem_access & mem_access 2: access listener can be required

[Keir Fraser <keir@xxxxxxx>]

I don't like to add extra creation flags unless it's really hard to avoid.
Could you have a domctl to specify this flag after the domain is created?

 -- Keir

On 04/01/2011 22:07, "Joe Epstein" <jepstein98@xxxxxxxxx> wrote:

> * Adds the ability to create a domain that requires an access listener;
>   that is, it pauses the VCPU if there is no memory event listener.
> 
> Signed-off-by: Joe Epstein <jepstein98@xxxxxxxxx>
> 
> diff -r 06b0916eb91d -r 85a7611248b8 xen/include/public/domctl.h
> --- a/xen/include/public/domctl.h Tue Jan 04 11:59:48 2011 -0800
> +++ b/xen/include/public/domctl.h Tue Jan 04 12:16:42 2011 -0800
> @@ -47,17 +47,20 @@
>      uint32_t ssidref;
>      xen_domain_handle_t handle;
>   /* Is this an HVM guest (as opposed to a PV guest)? */
> -#define _XEN_DOMCTL_CDF_hvm_guest     0
> -#define XEN_DOMCTL_CDF_hvm_guest      (1U<<_XEN_DOMCTL_CDF_hvm_guest)
> +#define _XEN_DOMCTL_CDF_hvm_guest        0
> +#define XEN_DOMCTL_CDF_hvm_guest         (1U<<_XEN_DOMCTL_CDF_hvm_guest)
>   /* Use hardware-assisted paging if available? */
> -#define _XEN_DOMCTL_CDF_hap           1
> -#define XEN_DOMCTL_CDF_hap            (1U<<_XEN_DOMCTL_CDF_hap)
> +#define _XEN_DOMCTL_CDF_hap              1
> +#define XEN_DOMCTL_CDF_hap               (1U<<_XEN_DOMCTL_CDF_hap)
>   /* Should domain memory integrity be verifed by tboot during Sx? */
> -#define _XEN_DOMCTL_CDF_s3_integrity  2
> -#define XEN_DOMCTL_CDF_s3_integrity   (1U<<_XEN_DOMCTL_CDF_s3_integrity)
> +#define _XEN_DOMCTL_CDF_s3_integrity     2
> +#define XEN_DOMCTL_CDF_s3_integrity      (1U<<_XEN_DOMCTL_CDF_s3_integrity)
>   /* Disable out-of-sync shadow page tables? */
> -#define _XEN_DOMCTL_CDF_oos_off       3
> -#define XEN_DOMCTL_CDF_oos_off        (1U<<_XEN_DOMCTL_CDF_oos_off)
> +#define _XEN_DOMCTL_CDF_oos_off          3
> +#define XEN_DOMCTL_CDF_oos_off           (1U<<_XEN_DOMCTL_CDF_oos_off)
> + /* Require mem_event listener for access; else pause */
> +#define _XEN_DOMCTL_CDF_access_required  4
> +#define XEN_DOMCTL_CDF_access_required
> (1U<<_XEN_DOMCTL_CDF_access_required)
>      uint32_t flags;
>  };
>  typedef struct xen_domctl_createdomain xen_domctl_createdomain_t;
> diff -r 06b0916eb91d -r 85a7611248b8 xen/include/xen/sched.h
> --- a/xen/include/xen/sched.h Tue Jan 04 11:59:48 2011 -0800
> +++ b/xen/include/xen/sched.h Tue Jan 04 12:16:42 2011 -0800
> @@ -403,22 +403,24 @@
>  struct domain *domain_create(
>      domid_t domid, unsigned int domcr_flags, ssidref_t ssidref);
>   /* DOMCRF_hvm: Create an HVM domain, as opposed to a PV domain. */
> -#define _DOMCRF_hvm           0
> -#define DOMCRF_hvm            (1U<<_DOMCRF_hvm)
> +#define _DOMCRF_hvm                0
> +#define DOMCRF_hvm                 (1U<<_DOMCRF_hvm)
>   /* DOMCRF_hap: Create a domain with hardware-assisted paging. */
> -#define _DOMCRF_hap           1
> -#define DOMCRF_hap            (1U<<_DOMCRF_hap)
> +#define _DOMCRF_hap                1
> +#define DOMCRF_hap                 (1U<<_DOMCRF_hap)
>   /* DOMCRF_s3_integrity: Create a domain with tboot memory integrity
> protection
>                          by tboot */
> -#define _DOMCRF_s3_integrity  2
> -#define DOMCRF_s3_integrity   (1U<<_DOMCRF_s3_integrity)
> +#define _DOMCRF_s3_integrity       2
> +#define DOMCRF_s3_integrity        (1U<<_DOMCRF_s3_integrity)
>   /* DOMCRF_dummy: Create a dummy domain (not scheduled; not on domain list)
> */
> -#define _DOMCRF_dummy         3
> -#define DOMCRF_dummy          (1U<<_DOMCRF_dummy)
> +#define _DOMCRF_dummy              3
> +#define DOMCRF_dummy               (1U<<_DOMCRF_dummy)
>   /* DOMCRF_oos_off: dont use out-of-sync optimization for shadow page tables
> */
> -#define _DOMCRF_oos_off         4
> -#define DOMCRF_oos_off          (1U<<_DOMCRF_oos_off)
> -
> +#define _DOMCRF_oos_off            4
> +#define DOMCRF_oos_off             (1U<<_DOMCRF_oos_off)
> +/* DOMCRF_access_required: mem_event listener required for access;
> else pause */
> +#define _DOMCRF_access_required    5
> +#define DOMCRF_access_required     (1U<<_DOMCRF_access_required)
>  /*
>   * rcu_lock_domain_by_id() is more efficient than get_domain_by_id().
>   * This is the preferred function if the returned domain reference
> diff -r 06b0916eb91d -r 85a7611248b8 xen/include/asm-x86/p2m.h
> --- a/xen/include/asm-x86/p2m.h Tue Jan 04 11:59:48 2011 -0800
> +++ b/xen/include/asm-x86/p2m.h Tue Jan 04 12:16:42 2011 -0800
> @@ -422,7 +422,7 @@
>  }
> 
>  /* Init the datastructures for later use by the p2m code */
> -int p2m_init(struct domain *d);
> +int p2m_init(struct domain *d, unsigned int domcr_flags);
> 
>  /* Allocate a new p2m table for a domain.
>   *
> diff -r 06b0916eb91d -r 85a7611248b8 xen/arch/x86/mm/p2m.c
> --- a/xen/arch/x86/mm/p2m.c Tue Jan 04 11:59:48 2011 -0800
> +++ b/xen/arch/x86/mm/p2m.c Tue Jan 04 12:16:42 2011 -0800
> @@ -1744,7 +1744,7 @@
>      return;
>  }
> 
> -int p2m_init(struct domain *d)
> +int p2m_init(struct domain *d, unsigned int domcr_flags)
>  {
>      struct p2m_domain *p2m;
> 
> @@ -1752,7 +1752,10 @@
>      if ( p2m == NULL )
>          return -ENOMEM;
>      p2m_initialise(d, p2m);
> -
> +
> +    if ( domcr_flags & DOMCRF_access_required )
> +        p2m->access_required = 1;
> +
>      return 0;
>  }
> 
> diff -r 06b0916eb91d -r 85a7611248b8 xen/arch/x86/mm/paging.c
> --- a/xen/arch/x86/mm/paging.c Tue Jan 04 11:59:48 2011 -0800
> +++ b/xen/arch/x86/mm/paging.c Tue Jan 04 12:16:42 2011 -0800
> @@ -647,7 +647,7 @@
>  {
>      int rc;
> 
> -    if ( (rc = p2m_init(d)) != 0 )
> +    if ( (rc = p2m_init(d, domcr_flags)) != 0 )
>          return rc;
> 
>      /* The order of the *_init calls below is important, as the later
> diff -r 06b0916eb91d -r 85a7611248b8 xen/common/domctl.c
> --- a/xen/common/domctl.c Tue Jan 04 11:59:48 2011 -0800
> +++ b/xen/common/domctl.c Tue Jan 04 12:16:42 2011 -0800
> @@ -398,7 +398,7 @@
>          if ( supervisor_mode_kernel ||
>               (op->u.createdomain.flags &
>               ~(XEN_DOMCTL_CDF_hvm_guest | XEN_DOMCTL_CDF_hap |
> -               XEN_DOMCTL_CDF_s3_integrity | XEN_DOMCTL_CDF_oos_off)) )
> +               XEN_DOMCTL_CDF_s3_integrity | XEN_DOMCTL_CDF_oos_off |
> XEN_DOMCTL_CDF_access_required)) )
>              break;
> 
>          dom = op->domain;
> @@ -434,6 +434,8 @@
>              domcr_flags |= DOMCRF_s3_integrity;
>          if ( op->u.createdomain.flags & XEN_DOMCTL_CDF_oos_off )
>              domcr_flags |= DOMCRF_oos_off;
> +        if ( op->u.createdomain.flags & XEN_DOMCTL_CDF_access_required )
> +            domcr_flags |= DOMCRF_access_required;
> 
>          ret = -ENOMEM;
>          d = domain_create(dom, domcr_flags, op->u.createdomain.ssidref);
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel