[PATCH v2 4/4] xen/pci: solve compilation error on ARM with HAS_PCI enabled.

[Rahul Singh <rahul.singh@xxxxxxx>]

If mem-sharing, mem-paging and log-dirty functionality is not enabled
for architecture when HAS_PCI is enabled, compiler will throw an error.

Move code to x86 specific directory to fix compilation error.

No functional change.

Signed-off-by: Rahul Singh <rahul.singh@xxxxxxx>
---

Changes in v2:
 - Move mem-sharing , men-paging and log-dirty specific code to x86 directory. 

---
 xen/drivers/passthrough/pci.c       |  8 +-------
 xen/drivers/passthrough/x86/iommu.c | 13 +++++++++++++
 xen/include/xen/iommu.h             |  2 ++
 3 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index 04d3e2c0f9..433989e654 100644
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -22,7 +22,6 @@
 #include <xen/iommu.h>
 #include <xen/irq.h>
 #include <xen/param.h>
-#include <xen/vm_event.h>
 #include <xen/delay.h>
 #include <xen/keyhandler.h>
 #include <xen/event.h>
@@ -1418,12 +1417,7 @@ static int assign_device(struct domain *d, u16 seg, u8 
bus, u8 devfn, u32 flag)
     if ( !is_iommu_enabled(d) )
         return 0;
 
-    /* Prevent device assign if mem paging or mem sharing have been 
-     * enabled for this domain */
-    if ( d != dom_io &&
-         unlikely(mem_sharing_enabled(d) ||
-                  vm_event_check_ring(d->vm_event_paging) ||
-                  p2m_get_hostp2m(d)->global_logdirty) )
+    if( !arch_iommu_usable(d) )
         return -EXDEV;
 
     /* device_assigned() should already have cleared the device for assignment 
*/
diff --git a/xen/drivers/passthrough/x86/iommu.c 
b/xen/drivers/passthrough/x86/iommu.c
index 875e67b53b..b3d151a14c 100644
--- a/xen/drivers/passthrough/x86/iommu.c
+++ b/xen/drivers/passthrough/x86/iommu.c
@@ -23,6 +23,7 @@
 #include <asm/hvm/io.h>
 #include <asm/io_apic.h>
 #include <asm/setup.h>
+#include <xen/vm_event.h>
 
 const struct iommu_init_ops *__initdata iommu_init_ops;
 struct iommu_ops __read_mostly iommu_ops;
@@ -315,6 +316,18 @@ int iommu_update_ire_from_msi(
            ? iommu_call(&iommu_ops, update_ire_from_msi, msi_desc, msg) : 0;
 }
 
+bool_t arch_iommu_usable(struct domain *d)
+{
+
+    /* Prevent device assign if mem paging or mem sharing have been
+     * enabled for this domain */
+    if ( d != dom_io && unlikely(mem_sharing_enabled(d) ||
+                        vm_event_check_ring(d->vm_event_paging) ||
+                        p2m_get_hostp2m(d)->global_logdirty) )
+        return false;
+    else
+        return true;
+}
 /*
  * Local variables:
  * mode: C
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index 191021870f..493528cee3 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -381,6 +381,8 @@ DECLARE_PER_CPU(bool_t, iommu_dont_flush_iotlb);
 extern struct spinlock iommu_pt_cleanup_lock;
 extern struct page_list_head iommu_pt_cleanup_list;
 
+bool_t arch_iommu_usable(struct domain *d);
+
 #endif /* _IOMMU_H_ */
 
 /*
-- 
2.17.1