1 files changed, 68 insertions, 39 deletions

diff --git a/hw/acpi/viot.c b/hw/acpi/viot.c
index c1af75206e..4e0bf69067 100644
--- a/hw/acpi/viot.c
+++ b/hw/acpi/viot.c
@@ -10,17 +10,40 @@
 #include "hw/pci/pci.h"
 #include "hw/pci/pci_host.h"
 
-struct viot_pci_ranges {
-    GArray *blob;
-    size_t count;
-    uint16_t output_node;
+struct viot_pci_host_range {
+    int min_bus;
+    int max_bus;
 };
 
+static void build_pci_host_range(GArray *table_data, int min_bus, int max_bus,
+                                 uint16_t output_node)
+{
+    /* Type */
+    build_append_int_noprefix(table_data, 1 /* PCI range */, 1);
+    /* Reserved */
+    build_append_int_noprefix(table_data, 0, 1);
+    /* Length */
+    build_append_int_noprefix(table_data, 24, 2);
+    /* Endpoint start */
+    build_append_int_noprefix(table_data, PCI_BUILD_BDF(min_bus, 0), 4);
+    /* PCI Segment start */
+    build_append_int_noprefix(table_data, 0, 2);
+    /* PCI Segment end */
+    build_append_int_noprefix(table_data, 0, 2);
+    /* PCI BDF start */
+    build_append_int_noprefix(table_data, PCI_BUILD_BDF(min_bus, 0), 2);
+    /* PCI BDF end */
+    build_append_int_noprefix(table_data, PCI_BUILD_BDF(max_bus, 0xff), 2);
+    /* Output node */
+    build_append_int_noprefix(table_data, output_node, 2);
+    /* Reserved */
+    build_append_int_noprefix(table_data, 0, 6);
+}
+
 /* Build PCI range for a given PCI host bridge */
-static int build_pci_range_node(Object *obj, void *opaque)
+static int enumerate_pci_host_bridges(Object *obj, void *opaque)
 {
-    struct viot_pci_ranges *pci_ranges = opaque;
-    GArray *blob = pci_ranges->blob;
+    GArray *pci_host_ranges = opaque;
 
     if (object_dynamic_cast(obj, TYPE_PCI_HOST_BRIDGE)) {
         PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus;
@@ -30,34 +53,31 @@ static int build_pci_range_node(Object *obj, void *opaque)
 
             pci_bus_range(bus, &min_bus, &max_bus);
 
-            /* Type */
-            build_append_int_noprefix(blob, 1 /* PCI range */, 1);
-            /* Reserved */
-            build_append_int_noprefix(blob, 0, 1);
-            /* Length */
-            build_append_int_noprefix(blob, 24, 2);
-            /* Endpoint start */
-            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 4);
-            /* PCI Segment start */
-            build_append_int_noprefix(blob, 0, 2);
-            /* PCI Segment end */
-            build_append_int_noprefix(blob, 0, 2);
-            /* PCI BDF start */
-            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 2);
-            /* PCI BDF end */
-            build_append_int_noprefix(blob, PCI_BUILD_BDF(max_bus, 0xff), 2);
-            /* Output node */
-            build_append_int_noprefix(blob, pci_ranges->output_node, 2);
-            /* Reserved */
-            build_append_int_noprefix(blob, 0, 6);
-
-            pci_ranges->count++;
+            const struct viot_pci_host_range pci_host_range = {
+                .min_bus = min_bus,
+                .max_bus = max_bus,
+            };
+            g_array_append_val(pci_host_ranges, pci_host_range);
         }
     }
 
     return 0;
 }
 
+static gint pci_host_range_compare(gconstpointer a, gconstpointer b)
+{
+    struct viot_pci_host_range *range_a = (struct viot_pci_host_range *)a;
+    struct viot_pci_host_range *range_b = (struct viot_pci_host_range *)b;
+
+    if (range_a->min_bus < range_b->min_bus) {
+        return -1;
+    } else if (range_a->min_bus > range_b->min_bus) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
 /*
  * Generate a VIOT table with one PCI-based virtio-iommu that manages PCI
  * endpoints.
@@ -72,19 +92,22 @@ void build_viot(MachineState *ms, GArray *table_data, BIOSLinker *linker,
     int viommu_off = 48;
     AcpiTable table = { .sig = "VIOT", .rev = 0,
                         .oem_id = oem_id, .oem_table_id = oem_table_id };
-    struct viot_pci_ranges pci_ranges = {
-        .output_node = viommu_off,
-        .blob = g_array_new(false, true /* clear */, 1),
-    };
+    GArray *pci_host_ranges =  g_array_new(false, true,
+                                           sizeof(struct viot_pci_host_range));
+    struct viot_pci_host_range *pci_host_range;
+    int i;
 
     /* Build the list of PCI ranges that this viommu manages */
-    object_child_foreach_recursive(OBJECT(ms), build_pci_range_node,
-                                   &pci_ranges);
+    object_child_foreach_recursive(OBJECT(ms), enumerate_pci_host_bridges,
+                                   pci_host_ranges);
+
+    /* Sort the pci host ranges by min_bus */
+    g_array_sort(pci_host_ranges, pci_host_range_compare);
 
     /* ACPI table header */
     acpi_table_begin(&table, table_data);
     /* Node count */
-    build_append_int_noprefix(table_data, pci_ranges.count + 1, 2);
+    build_append_int_noprefix(table_data, pci_host_ranges->len + 1, 2);
     /* Node offset */
     build_append_int_noprefix(table_data, viommu_off, 2);
     /* Reserved */
@@ -105,9 +128,15 @@ void build_viot(MachineState *ms, GArray *table_data, BIOSLinker *linker,
     build_append_int_noprefix(table_data, 0, 8);
 
     /* PCI ranges found above */
-    g_array_append_vals(table_data, pci_ranges.blob->data,
-                        pci_ranges.blob->len);
-    g_array_free(pci_ranges.blob, true);
+    for (i = 0; i < pci_host_ranges->len; i++) {
+        pci_host_range = &g_array_index(pci_host_ranges,
+                                        struct viot_pci_host_range, i);
+
+        build_pci_host_range(table_data, pci_host_range->min_bus,
+                             pci_host_range->max_bus, viommu_off);
+    }
+
+    g_array_free(pci_host_ranges, true);
 
     acpi_table_end(linker, &table);
 }