Provide the function and use it in vtd_init().  Used to reset both
context entry cache and iotlb cache for the whole IOMMU unit.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 hw/i386/intel_iommu.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 3dfada19a6..1137861a9d 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -227,6 +227,14 @@ static void vtd_reset_iotlb(IntelIOMMUState *s)
     vtd_iommu_unlock(s);
 }
 
+static void vtd_reset_caches(IntelIOMMUState *s)
+{
+    vtd_iommu_lock(s);
+    vtd_reset_iotlb_locked(s);
+    vtd_reset_context_cache_locked(s);
+    vtd_iommu_unlock(s);
+}
+
 static uint64_t vtd_get_iotlb_key(uint64_t gfn, uint16_t source_id,
                                   uint32_t level)
 {
@@ -3160,10 +3168,7 @@ static void vtd_init(IntelIOMMUState *s)
         s->cap |= VTD_CAP_CM;
     }
 
-    vtd_iommu_lock(s);
-    vtd_reset_context_cache_locked(s);
-    vtd_reset_iotlb_locked(s);
-    vtd_iommu_unlock(s);
+    vtd_reset_caches(s);
 
     /* Define registers with default values and bit semantics */
     vtd_define_long(s, DMAR_VER_REG, 0x10UL, 0, 0);
-- 
2.17.1