diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
index ce59f2b503..71f4a78425 100644
--- a/xen/arch/arm/p2m.c
+++ b/xen/arch/arm/p2m.c
@@ -1061,7 +1061,7 @@ static int __p2m_set_entry(struct p2m_domain *p2m,
             flush_flags |= IOMMU_FLUSHF_added;
 
         rc = iommu_iotlb_flush(p2m->domain, _dfn(gfn_x(sgfn)),
-                               1UL << page_order, flush_flags);
+                               page_order, 1, flush_flags);
     }
     else
         rc = 0;
diff --git a/xen/arch/x86/mm/p2m-ept.c b/xen/arch/x86/mm/p2m-ept.c
index b8154a7ecc..b2ac912cde 100644
--- a/xen/arch/x86/mm/p2m-ept.c
+++ b/xen/arch/x86/mm/p2m-ept.c
@@ -843,7 +843,7 @@ out:
          need_modify_vtd_table )
     {
         if ( iommu_use_hap_pt(d) )
-            rc = iommu_iotlb_flush(d, _dfn(gfn), (1u << order),
+            rc = iommu_iotlb_flush(d, _dfn(gfn), (1u << order), 1,
                                    (iommu_flags ? IOMMU_FLUSHF_added : 0) |
                                    (vtd_pte_present ? IOMMU_FLUSHF_modified
                                                     : 0));
diff --git a/xen/common/memory.c b/xen/common/memory.c
index 714077c1e5..8de334ff10 100644
--- a/xen/common/memory.c
+++ b/xen/common/memory.c
@@ -851,12 +851,12 @@ int xenmem_add_to_physmap(struct domain *d, struct xen_add_to_physmap *xatp,
 
         this_cpu(iommu_dont_flush_iotlb) = 0;
 
-        ret = iommu_iotlb_flush(d, _dfn(xatp->idx - done), done,
+        ret = iommu_iotlb_flush(d, _dfn(xatp->idx - done), 0, done,
                                 IOMMU_FLUSHF_added | IOMMU_FLUSHF_modified);
         if ( unlikely(ret) && rc >= 0 )
             rc = ret;
 
-        ret = iommu_iotlb_flush(d, _dfn(xatp->gpfn - done), done,
+        ret = iommu_iotlb_flush(d, _dfn(xatp->gpfn - done), 0, done,
                                 IOMMU_FLUSHF_added | IOMMU_FLUSHF_modified);
         if ( unlikely(ret) && rc >= 0 )
             rc = ret;
diff --git a/xen/drivers/passthrough/amd/iommu.h b/xen/drivers/passthrough/amd/iommu.h
index e2d174f3b4..f1f0415469 100644
--- a/xen/drivers/passthrough/amd/iommu.h
+++ b/xen/drivers/passthrough/amd/iommu.h
@@ -231,7 +231,7 @@ int amd_iommu_reserve_domain_unity_map(struct domain *domain,
                                        paddr_t phys_addr, unsigned long size,
                                        int iw, int ir);
 int __must_check amd_iommu_flush_iotlb_pages(struct domain *d, dfn_t dfn,
-                                             unsigned int page_count,
+                                             unsigned long page_count,
                                              unsigned int flush_flags);
 int __must_check amd_iommu_flush_iotlb_all(struct domain *d);
 
diff --git a/xen/drivers/passthrough/amd/iommu_map.c b/xen/drivers/passthrough/amd/iommu_map.c
index 54b991294a..0cb948d114 100644
--- a/xen/drivers/passthrough/amd/iommu_map.c
+++ b/xen/drivers/passthrough/amd/iommu_map.c
@@ -351,7 +351,7 @@ int amd_iommu_unmap_page(struct domain *d, dfn_t dfn,
     return 0;
 }
 
-static unsigned long flush_count(unsigned long dfn, unsigned int page_count,
+static unsigned long flush_count(unsigned long dfn, unsigned long page_count,
                                  unsigned int order)
 {
     unsigned long start = dfn >> order;
@@ -362,7 +362,7 @@ static unsigned long flush_count(unsigned long dfn, unsigned int page_count,
 }
 
 int amd_iommu_flush_iotlb_pages(struct domain *d, dfn_t dfn,
-                                unsigned int page_count,
+                                unsigned long page_count,
                                 unsigned int flush_flags)
 {
     unsigned long dfn_l = dfn_x(dfn);
diff --git a/xen/drivers/passthrough/arm/ipmmu-vmsa.c b/xen/drivers/passthrough/arm/ipmmu-vmsa.c
index b2a65dfaaf..346165c3fa 100644
--- a/xen/drivers/passthrough/arm/ipmmu-vmsa.c
+++ b/xen/drivers/passthrough/arm/ipmmu-vmsa.c
@@ -945,7 +945,7 @@ static int __must_check ipmmu_iotlb_flush_all(struct domain *d)
 }
 
 static int __must_check ipmmu_iotlb_flush(struct domain *d, dfn_t dfn,
-                                          unsigned int page_count,
+                                          unsigned long page_count,
                                           unsigned int flush_flags)
 {
     ASSERT(flush_flags);
diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c
index 94662a8501..06f9bda47d 100644
--- a/xen/drivers/passthrough/arm/smmu.c
+++ b/xen/drivers/passthrough/arm/smmu.c
@@ -2534,7 +2534,7 @@ static int __must_check arm_smmu_iotlb_flush_all(struct domain *d)
 }
 
 static int __must_check arm_smmu_iotlb_flush(struct domain *d, dfn_t dfn,
-					     unsigned int page_count,
+					     unsigned long page_count,
 					     unsigned int flush_flags)
 {
 	ASSERT(flush_flags);
diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index e2c0193a09..568a4a5661 100644
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -235,8 +235,8 @@ void iommu_domain_destroy(struct domain *d)
 }
 
 int iommu_map(struct domain *d, dfn_t dfn, mfn_t mfn,
-              unsigned int page_order, unsigned int flags,
-              unsigned int *flush_flags)
+              unsigned int page_order, unsigned int page_count,
+              unsigned int flags, unsigned int *flush_flags)
 {
     const struct domain_iommu *hd = dom_iommu(d);
     unsigned long i;
@@ -248,7 +248,7 @@ int iommu_map(struct domain *d, dfn_t dfn, mfn_t mfn,
     ASSERT(IS_ALIGNED(dfn_x(dfn), (1ul << page_order)));
     ASSERT(IS_ALIGNED(mfn_x(mfn), (1ul << page_order)));
 
-    for ( i = 0; i < (1ul << page_order); i++ )
+    for ( i = 0; i < ((unsigned long)page_count << page_order); i++ )
     {
         rc = iommu_call(hd->platform_ops, map_page, d, dfn_add(dfn, i),
                         mfn_add(mfn, i), flags, flush_flags);
@@ -285,16 +285,16 @@ int iommu_legacy_map(struct domain *d, dfn_t dfn, mfn_t mfn,
                      unsigned int page_order, unsigned int flags)
 {
     unsigned int flush_flags = 0;
-    int rc = iommu_map(d, dfn, mfn, page_order, flags, &flush_flags);
+    int rc = iommu_map(d, dfn, mfn, page_order, 1, flags, &flush_flags);
 
     if ( !this_cpu(iommu_dont_flush_iotlb) && !rc )
-        rc = iommu_iotlb_flush(d, dfn, (1u << page_order), flush_flags);
+        rc = iommu_iotlb_flush(d, dfn, (1u << page_order), 1, flush_flags);
 
     return rc;
 }
 
 int iommu_unmap(struct domain *d, dfn_t dfn, unsigned int page_order,
-                unsigned int *flush_flags)
+                unsigned int page_count, unsigned int *flush_flags)
 {
     const struct domain_iommu *hd = dom_iommu(d);
     unsigned long i;
@@ -305,7 +305,7 @@ int iommu_unmap(struct domain *d, dfn_t dfn, unsigned int page_order,
 
     ASSERT(IS_ALIGNED(dfn_x(dfn), (1ul << page_order)));
 
-    for ( i = 0; i < (1ul << page_order); i++ )
+    for ( i = 0; i < ((unsigned long)page_count << page_order); i++ )
     {
         int err = iommu_call(hd->platform_ops, unmap_page, d, dfn_add(dfn, i),
                              flush_flags);
@@ -338,10 +338,10 @@ int iommu_unmap(struct domain *d, dfn_t dfn, unsigned int page_order,
 int iommu_legacy_unmap(struct domain *d, dfn_t dfn, unsigned int page_order)
 {
     unsigned int flush_flags = 0;
-    int rc = iommu_unmap(d, dfn, page_order, &flush_flags);
+    int rc = iommu_unmap(d, dfn, page_order, 1, &flush_flags);
 
     if ( !this_cpu(iommu_dont_flush_iotlb) && ! rc )
-        rc = iommu_iotlb_flush(d, dfn, (1u << page_order), flush_flags);
+        rc = iommu_iotlb_flush(d, dfn, (1u << page_order), 1, flush_flags);
 
     return rc;
 }
@@ -357,8 +357,8 @@ int iommu_lookup_page(struct domain *d, dfn_t dfn, mfn_t *mfn,
     return iommu_call(hd->platform_ops, lookup_page, d, dfn, mfn, flags);
 }
 
-int iommu_iotlb_flush(struct domain *d, dfn_t dfn, unsigned int page_count,
-                      unsigned int flush_flags)
+int iommu_iotlb_flush(struct domain *d, dfn_t dfn, unsigned int page_order,
+                      unsigned int page_count, unsigned int flush_flags)
 {
     const struct domain_iommu *hd = dom_iommu(d);
     int rc;
@@ -370,14 +370,15 @@ int iommu_iotlb_flush(struct domain *d, dfn_t dfn, unsigned int page_count,
     if ( dfn_eq(dfn, INVALID_DFN) )
         return -EINVAL;
 
-    rc = iommu_call(hd->platform_ops, iotlb_flush, d, dfn, page_count,
-                    flush_flags);
+    rc = iommu_call(hd->platform_ops, iotlb_flush, d, dfn,
+                    (unsigned long)page_count << page_order, flush_flags);
     if ( unlikely(rc) )
     {
         if ( !d->is_shutting_down && printk_ratelimit() )
             printk(XENLOG_ERR
-                   "d%d: IOMMU IOTLB flush failed: %d, dfn %"PRI_dfn", page count %u flags %x\n",
-                   d->domain_id, rc, dfn_x(dfn), page_count, flush_flags);
+                   "d%d: IOMMU IOTLB flush failed: %d, dfn %"PRI_dfn", page order %u, page count %u flags %x\n",
+                   d->domain_id, rc, dfn_x(dfn), page_order, page_count,
+                   flush_flags);
 
         if ( !is_hardware_domain(d) )
             domain_crash(d);
diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index 607e8b5e65..68cf0e535a 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -584,7 +584,7 @@ static int __must_check iommu_flush_all(void)
 
 static int __must_check iommu_flush_iotlb(struct domain *d, dfn_t dfn,
                                           bool_t dma_old_pte_present,
-                                          unsigned int page_count)
+                                          unsigned long page_count)
 {
     struct domain_iommu *hd = dom_iommu(d);
     struct acpi_drhd_unit *drhd;
@@ -632,7 +632,7 @@ static int __must_check iommu_flush_iotlb(struct domain *d, dfn_t dfn,
 
 static int __must_check iommu_flush_iotlb_pages(struct domain *d,
                                                 dfn_t dfn,
-                                                unsigned int page_count,
+                                                unsigned long page_count,
                                                 unsigned int flush_flags)
 {
     ASSERT(page_count && !dfn_eq(dfn, INVALID_DFN));
diff --git a/xen/drivers/passthrough/x86/iommu.c b/xen/drivers/passthrough/x86/iommu.c
index c0d4865dd7..5d1a7cb296 100644
--- a/xen/drivers/passthrough/x86/iommu.c
+++ b/xen/drivers/passthrough/x86/iommu.c
@@ -244,7 +244,7 @@ void __hwdom_init arch_iommu_hwdom_init(struct domain *d)
         else if ( paging_mode_translate(d) )
             rc = set_identity_p2m_entry(d, pfn, p2m_access_rw, 0);
         else
-            rc = iommu_map(d, _dfn(pfn), _mfn(pfn), PAGE_ORDER_4K,
+            rc = iommu_map(d, _dfn(pfn), _mfn(pfn), PAGE_ORDER_4K, 1,
                            IOMMUF_readable | IOMMUF_writable, &flush_flags);
 
         if ( rc )
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index 1831dc66b0..d9c2e764aa 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -146,10 +146,10 @@ enum
 #define IOMMU_FLUSHF_modified (1u << _IOMMU_FLUSHF_modified)
 
 int __must_check iommu_map(struct domain *d, dfn_t dfn, mfn_t mfn,
-                           unsigned int page_order, unsigned int flags,
-                           unsigned int *flush_flags);
+                           unsigned int page_order, unsigned int page_count,
+                           unsigned int flags, unsigned int *flush_flags);
 int __must_check iommu_unmap(struct domain *d, dfn_t dfn,
-                             unsigned int page_order,
+                             unsigned int page_order, unsigned int page_count,
                              unsigned int *flush_flags);
 
 int __must_check iommu_legacy_map(struct domain *d, dfn_t dfn, mfn_t mfn,
@@ -162,6 +162,7 @@ int __must_check iommu_lookup_page(struct domain *d, dfn_t dfn, mfn_t *mfn,
                                    unsigned int *flags);
 
 int __must_check iommu_iotlb_flush(struct domain *d, dfn_t dfn,
+                                   unsigned int page_order,
                                    unsigned int page_count,
                                    unsigned int flush_flags);
 int __must_check iommu_iotlb_flush_all(struct domain *d,
@@ -281,7 +282,7 @@ struct iommu_ops {
     void (*share_p2m)(struct domain *d);
     void (*crash_shutdown)(void);
     int __must_check (*iotlb_flush)(struct domain *d, dfn_t dfn,
-                                    unsigned int page_count,
+                                    unsigned long page_count,
                                     unsigned int flush_flags);
     int __must_check (*iotlb_flush_all)(struct domain *d);
     int (*get_reserved_device_memory)(iommu_grdm_t *, void *);
