Re: [Xen-devel] [for-4.7 v3 1/2] xen: XENMEM_add_to_physmap_batch: Mark 'foreign_id' as reserved for dev_mmio

2016-05-30 Thread Jan Beulich 
>>> On 27.05.16 at 18:06,  wrote:
> The field 'foreign_id' is not used when the space is dev_mmio. As the
> space is not yet part of the stable ABI, the field is marked as reserved
> for future use.
> 
> The value should always be 0, other values will return -EOPNOTSUPP.
> 
> Signed-off-by: Julien Grall 

Acked-by: Jan Beulich 


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Re: [Xen-devel] [for-4.7 v3 1/2] xen: XENMEM_add_to_physmap_batch: Mark 'foreign_id' as reserved for dev_mmio

2016-05-30 Thread Stefano Stabellini 
On Fri, 27 May 2016, Julien Grall wrote:
> The field 'foreign_id' is not used when the space is dev_mmio. As the
> space is not yet part of the stable ABI, the field is marked as reserved
> for future use.
> 
> The value should always be 0, other values will return -EOPNOTSUPP.
> 
> Signed-off-by: Julien Grall 

Acked-by: Stefano Stabellini 


> Changes in v3:
> - s/add_to_physmap_batch_extra/xen_add_to_physmap_batch_extra/
> - Add a comment in compat
> 
> Changes in v2:
> - Return -EOPNOTSUPP rather than -ENOSYS
> - Introduce a union in the structure xenmem_add_to_physmap_batch
> ---
>  xen/arch/arm/mm.c   |  9 +++--
>  xen/arch/x86/mm.c   |  4 ++--
>  xen/common/compat/memory.c  |  7 +++
>  xen/common/memory.c | 12 +---
>  xen/include/public/memory.h | 10 +-
>  xen/include/xen/mm.h|  3 ++-
>  6 files changed, 36 insertions(+), 9 deletions(-)
> 
> diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
> index b46e23e..0aa8092 100644
> --- a/xen/arch/arm/mm.c
> +++ b/xen/arch/arm/mm.c
> @@ -1047,7 +1047,7 @@ void share_xen_page_with_privileged_guests(
>  int xenmem_add_to_physmap_one(
>  struct domain *d,
>  unsigned int space,
> -domid_t foreign_domid,
> +union xen_add_to_physmap_batch_extra extra,
>  unsigned long idx,
>  xen_pfn_t gpfn)
>  {
> @@ -1103,7 +1103,8 @@ int xenmem_add_to_physmap_one(
>  {
>  struct domain *od;
>  p2m_type_t p2mt;
> -od = rcu_lock_domain_by_any_id(foreign_domid);
> +
> +od = rcu_lock_domain_by_any_id(extra.foreign_domid);
>  if ( od == NULL )
>  return -ESRCH;
>  
> @@ -1143,6 +1144,10 @@ int xenmem_add_to_physmap_one(
>  break;
>  }
>  case XENMAPSPACE_dev_mmio:
> +/* extra should be 0. Reserved for future use. */
> +if ( extra.res0 )
> +return -EOPNOTSUPP;
> +
>  rc = map_dev_mmio_region(d, gpfn, 1, idx);
>  return rc;
>  
> diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
> index 03a4d5b..8d10a3e 100644
> --- a/xen/arch/x86/mm.c
> +++ b/xen/arch/x86/mm.c
> @@ -4769,7 +4769,7 @@ static int handle_iomem_range(unsigned long s, unsigned 
> long e, void *p)
>  int xenmem_add_to_physmap_one(
>  struct domain *d,
>  unsigned int space,
> -domid_t foreign_domid,
> +union xen_add_to_physmap_batch_extra extra,
>  unsigned long idx,
>  xen_pfn_t gpfn)
>  {
> @@ -4830,7 +4830,7 @@ int xenmem_add_to_physmap_one(
>  break;
>  }
>  case XENMAPSPACE_gmfn_foreign:
> -return p2m_add_foreign(d, idx, gpfn, foreign_domid);
> +return p2m_add_foreign(d, idx, gpfn, extra.foreign_domid);
>  default:
>  break;
>  }
> diff --git a/xen/common/compat/memory.c b/xen/common/compat/memory.c
> index 19a914d..20c7671 100644
> --- a/xen/common/compat/memory.c
> +++ b/xen/common/compat/memory.c
> @@ -253,6 +253,13 @@ int compat_memory_op(unsigned int cmd, 
> XEN_GUEST_HANDLE_PARAM(void) compat)
>  unsigned int size = cmp.atpb.size;
>  xen_ulong_t *idxs = (void *)(nat.atpb + 1);
>  xen_pfn_t *gpfns = (void *)(idxs + limit);
> +/*
> + * The union will always be 16-bit width. So it is not
> + * necessary to have the exact field which correspond to the
> + * space.
> + */
> +enum XLAT_add_to_physmap_batch_u u =
> +XLAT_add_to_physmap_batch_u_res0;
>  
>  if ( copy_from_guest(, compat, 1) ||
>   !compat_handle_okay(cmp.atpb.idxs, size) ||
> diff --git a/xen/common/memory.c b/xen/common/memory.c
> index 644f81a..ccc6436 100644
> --- a/xen/common/memory.c
> +++ b/xen/common/memory.c
> @@ -639,9 +639,15 @@ static int xenmem_add_to_physmap(struct domain *d,
>  {
>  unsigned int done = 0;
>  long rc = 0;
> +union xen_add_to_physmap_batch_extra extra;
> +
> +if ( xatp->space != XENMAPSPACE_gmfn_foreign )
> +extra.res0 = 0;
> +else
> +extra.foreign_domid = DOMID_INVALID;
>  
>  if ( xatp->space != XENMAPSPACE_gmfn_range )
> -return xenmem_add_to_physmap_one(d, xatp->space, DOMID_INVALID,
> +return xenmem_add_to_physmap_one(d, xatp->space, extra,
>   xatp->idx, xatp->gpfn);
>  
>  if ( xatp->size < start )
> @@ -658,7 +664,7 @@ static int xenmem_add_to_physmap(struct domain *d,
>  
>  while ( xatp->size > done )
>  {
> -rc = xenmem_add_to_physmap_one(d, xatp->space, DOMID_INVALID,
> +rc = xenmem_add_to_physmap_one(d, xatp->space, extra,
> xatp->idx, xatp->gpfn);
>  if ( rc < 0 )
>  break;
> @@ -719,7 +725,7 @@ static int xenmem_add_to_physmap_batch(struct domain *d,
>  }
>  
>  rc =

[Xen-devel] [for-4.7 v3 1/2] xen: XENMEM_add_to_physmap_batch: Mark 'foreign_id' as reserved for dev_mmio

2016-05-27 Thread Julien Grall 
The field 'foreign_id' is not used when the space is dev_mmio. As the
space is not yet part of the stable ABI, the field is marked as reserved
for future use.

The value should always be 0, other values will return -EOPNOTSUPP.

Signed-off-by: Julien Grall 

---
Changes in v3:
- s/add_to_physmap_batch_extra/xen_add_to_physmap_batch_extra/
- Add a comment in compat

Changes in v2:
- Return -EOPNOTSUPP rather than -ENOSYS
- Introduce a union in the structure xenmem_add_to_physmap_batch
---
 xen/arch/arm/mm.c   |  9 +++--
 xen/arch/x86/mm.c   |  4 ++--
 xen/common/compat/memory.c  |  7 +++
 xen/common/memory.c | 12 +---
 xen/include/public/memory.h | 10 +-
 xen/include/xen/mm.h|  3 ++-
 6 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index b46e23e..0aa8092 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -1047,7 +1047,7 @@ void share_xen_page_with_privileged_guests(
 int xenmem_add_to_physmap_one(
 struct domain *d,
 unsigned int space,
-domid_t foreign_domid,
+union xen_add_to_physmap_batch_extra extra,
 unsigned long idx,
 xen_pfn_t gpfn)
 {
@@ -1103,7 +1103,8 @@ int xenmem_add_to_physmap_one(
 {
 struct domain *od;
 p2m_type_t p2mt;
-od = rcu_lock_domain_by_any_id(foreign_domid);
+
+od = rcu_lock_domain_by_any_id(extra.foreign_domid);
 if ( od == NULL )
 return -ESRCH;
 
@@ -1143,6 +1144,10 @@ int xenmem_add_to_physmap_one(
 break;
 }
 case XENMAPSPACE_dev_mmio:
+/* extra should be 0. Reserved for future use. */
+if ( extra.res0 )
+return -EOPNOTSUPP;
+
 rc = map_dev_mmio_region(d, gpfn, 1, idx);
 return rc;
 
diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
index 03a4d5b..8d10a3e 100644
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -4769,7 +4769,7 @@ static int handle_iomem_range(unsigned long s, unsigned 
long e, void *p)
 int xenmem_add_to_physmap_one(
 struct domain *d,
 unsigned int space,
-domid_t foreign_domid,
+union xen_add_to_physmap_batch_extra extra,
 unsigned long idx,
 xen_pfn_t gpfn)
 {
@@ -4830,7 +4830,7 @@ int xenmem_add_to_physmap_one(
 break;
 }
 case XENMAPSPACE_gmfn_foreign:
-return p2m_add_foreign(d, idx, gpfn, foreign_domid);
+return p2m_add_foreign(d, idx, gpfn, extra.foreign_domid);
 default:
 break;
 }
diff --git a/xen/common/compat/memory.c b/xen/common/compat/memory.c
index 19a914d..20c7671 100644
--- a/xen/common/compat/memory.c
+++ b/xen/common/compat/memory.c
@@ -253,6 +253,13 @@ int compat_memory_op(unsigned int cmd, 
XEN_GUEST_HANDLE_PARAM(void) compat)
 unsigned int size = cmp.atpb.size;
 xen_ulong_t *idxs = (void *)(nat.atpb + 1);
 xen_pfn_t *gpfns = (void *)(idxs + limit);
+/*
+ * The union will always be 16-bit width. So it is not
+ * necessary to have the exact field which correspond to the
+ * space.
+ */
+enum XLAT_add_to_physmap_batch_u u =
+XLAT_add_to_physmap_batch_u_res0;
 
 if ( copy_from_guest(, compat, 1) ||
  !compat_handle_okay(cmp.atpb.idxs, size) ||
diff --git a/xen/common/memory.c b/xen/common/memory.c
index 644f81a..ccc6436 100644
--- a/xen/common/memory.c
+++ b/xen/common/memory.c
@@ -639,9 +639,15 @@ static int xenmem_add_to_physmap(struct domain *d,
 {
 unsigned int done = 0;
 long rc = 0;
+union xen_add_to_physmap_batch_extra extra;
+
+if ( xatp->space != XENMAPSPACE_gmfn_foreign )
+extra.res0 = 0;
+else
+extra.foreign_domid = DOMID_INVALID;
 
 if ( xatp->space != XENMAPSPACE_gmfn_range )
-return xenmem_add_to_physmap_one(d, xatp->space, DOMID_INVALID,
+return xenmem_add_to_physmap_one(d, xatp->space, extra,
  xatp->idx, xatp->gpfn);
 
 if ( xatp->size < start )
@@ -658,7 +664,7 @@ static int xenmem_add_to_physmap(struct domain *d,
 
 while ( xatp->size > done )
 {
-rc = xenmem_add_to_physmap_one(d, xatp->space, DOMID_INVALID,
+rc = xenmem_add_to_physmap_one(d, xatp->space, extra,
xatp->idx, xatp->gpfn);
 if ( rc < 0 )
 break;
@@ -719,7 +725,7 @@ static int xenmem_add_to_physmap_batch(struct domain *d,
 }
 
 rc = xenmem_add_to_physmap_one(d, xatpb->space,
-   xatpb->foreign_domid,
+   xatpb->u,
idx, gpfn);
 
 if ( unlikely(__copy_to_guest_offset(xatpb->errs, 0, , 1)) )
diff --git a/xen/include/public/memory.h b/xen/include/public/memory.h
index fe52ee1..5f7e0d2