[PULL 08/17] vfio/common: Add helper to consolidate iova/end calculation

[Alex Williamson <alex.williamson@redhat.com>]

From: Joao Martins <joao.m.martins@oracle.com>

In preparation to be used in device dirty tracking, move the code that
calculate a iova/end range from the container/section.  This avoids
duplication on the common checks across listener callbacks.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-9-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---
 hw/vfio/common.c |   41 +++++++++++++++++++++++++++--------------
 1 file changed, 27 insertions(+), 14 deletions(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index d38b7c1969b9..63831eab78a1 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -962,6 +962,31 @@ static bool vfio_listener_valid_section(MemoryRegionSection *section,
     return true;
 }
 
+static bool vfio_get_section_iova_range(VFIOContainer *container,
+                                        MemoryRegionSection *section,
+                                        hwaddr *out_iova, hwaddr *out_end,
+                                        Int128 *out_llend)
+{
+    Int128 llend;
+    hwaddr iova;
+
+    iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space);
+    llend = int128_make64(section->offset_within_address_space);
+    llend = int128_add(llend, section->size);
+    llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask()));
+
+    if (int128_ge(int128_make64(iova), llend)) {
+        return false;
+    }
+
+    *out_iova = iova;
+    *out_end = int128_get64(int128_sub(llend, int128_one()));
+    if (out_llend) {
+        *out_llend = llend;
+    }
+    return true;
+}
+
 static void vfio_listener_region_add(MemoryListener *listener,
                                      MemoryRegionSection *section)
 {
@@ -977,12 +1002,7 @@ static void vfio_listener_region_add(MemoryListener *listener,
         return;
     }
 
-    iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space);
-    llend = int128_make64(section->offset_within_address_space);
-    llend = int128_add(llend, section->size);
-    llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask()));
-
-    if (int128_ge(int128_make64(iova), llend)) {
+    if (!vfio_get_section_iova_range(container, section, &iova, &end, &llend)) {
         if (memory_region_is_ram_device(section->mr)) {
             trace_vfio_listener_region_add_no_dma_map(
                 memory_region_name(section->mr),
@@ -992,7 +1012,6 @@ static void vfio_listener_region_add(MemoryListener *listener,
         }
         return;
     }
-    end = int128_get64(int128_sub(llend, int128_one()));
 
     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
         hwaddr pgsize = 0;
@@ -1219,15 +1238,9 @@ static void vfio_listener_region_del(MemoryListener *listener,
          */
     }
 
-    iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space);
-    llend = int128_make64(section->offset_within_address_space);
-    llend = int128_add(llend, section->size);
-    llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask()));
-
-    if (int128_ge(int128_make64(iova), llend)) {
+    if (!vfio_get_section_iova_range(container, section, &iova, &end, &llend)) {
         return;
     }
-    end = int128_get64(int128_sub(llend, int128_one()));
 
     llsize = int128_sub(llend, int128_make64(iova));