From: Keir Fraser <keir.fraser@citrix.com>
Date: Tue, 16 Jun 2009 13:04:15 +0000 (+0100)
Subject: x86: Allow guests to allocate up to 2MB (superpage) memory extents.
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~13757
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/success/%22http:/www.example.com/cgi/success?a=commitdiff_plain;h=50f27130b5c3fe5f5f6c7faaf500f6fe5521b8b9;p=xen.git

x86: Allow guests to allocate up to 2MB (superpage) memory extents.

Signed-off-by: Keir Fraser <keir.fraser@eu.citrix.com>
---

diff --git a/xen/common/memory.c b/xen/common/memory.c
index 0dd2b9282f..9717dc2be8 100644
--- a/xen/common/memory.c
+++ b/xen/common/memory.c
@@ -50,8 +50,7 @@ static void increase_reservation(struct memop_args *a)
                                      a->nr_extents-1) )
         return;
 
-    if ( (a->extent_order != 0) &&
-         !multipage_allocation_permitted(current->domain) )
+    if ( !multipage_allocation_permitted(current->domain, a->extent_order) )
         return;
 
     for ( i = a->nr_done; i < a->nr_extents; i++ )
@@ -96,8 +95,7 @@ static void populate_physmap(struct memop_args *a)
                                      a->nr_extents-1) )
         return;
 
-    if ( (a->extent_order != 0) &&
-         !multipage_allocation_permitted(current->domain) )
+    if ( !multipage_allocation_permitted(current->domain, a->extent_order) )
         return;
 
     for ( i = a->nr_done; i < a->nr_extents; i++ )
@@ -247,8 +245,10 @@ static long memory_exchange(XEN_GUEST_HANDLE(xen_memory_exchange_t) arg)
     }
 
     /* Only privileged guests can allocate multi-page contiguous extents. */
-    if ( ((exch.in.extent_order != 0) || (exch.out.extent_order != 0)) &&
-         !multipage_allocation_permitted(current->domain) )
+    if ( !multipage_allocation_permitted(current->domain,
+                                         exch.in.extent_order) ||
+         !multipage_allocation_permitted(current->domain,
+                                         exch.out.extent_order) )
     {
         rc = -EPERM;
         goto fail_early;
diff --git a/xen/include/asm-ia64/iocap.h b/xen/include/asm-ia64/iocap.h
index 4f140b8476..ae7a871e0c 100644
--- a/xen/include/asm-ia64/iocap.h
+++ b/xen/include/asm-ia64/iocap.h
@@ -15,4 +15,9 @@ extern int ioports_deny_access(struct domain *d,
 #define ioports_access_permitted(d, s, e)               \
     rangeset_contains_range((d)->arch.ioport_caps, s, e)
 
+#define multipage_allocation_permitted(d, order)        \
+    (((order) == 0) ||                                  \
+     !rangeset_is_empty((d)->iomem_caps) ||             \
+     !rangeset_is_empty((d)->arch.ioport_caps))
+
 #endif /* __IA64_IOCAP_H__ */
diff --git a/xen/include/asm-x86/iocap.h b/xen/include/asm-x86/iocap.h
index eee47228d4..591ae17368 100644
--- a/xen/include/asm-x86/iocap.h
+++ b/xen/include/asm-x86/iocap.h
@@ -18,4 +18,9 @@
     (!rangeset_is_empty((d)->iomem_caps) ||             \
      !rangeset_is_empty((d)->arch.ioport_caps))
 
+#define multipage_allocation_permitted(d, order)        \
+    (((order) <= 9) || /* allow 2MB superpages */       \
+     !rangeset_is_empty((d)->iomem_caps) ||             \
+     !rangeset_is_empty((d)->arch.ioport_caps))
+
 #endif /* __X86_IOCAP_H__ */
diff --git a/xen/include/xen/iocap.h b/xen/include/xen/iocap.h
index c32604d9c9..63bb49f140 100644
--- a/xen/include/xen/iocap.h
+++ b/xen/include/xen/iocap.h
@@ -28,8 +28,4 @@
 #define irq_access_permitted(d, i)                      \
     rangeset_contains_singleton((d)->irq_caps, i)
 
-#define multipage_allocation_permitted(d)               \
-    (!rangeset_is_empty((d)->iomem_caps) ||             \
-     !rangeset_is_empty((d)->arch.ioport_caps))
-
 #endif /* __XEN_IOCAP_H__ */