Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pc,pci,virtio: features, fixes

virtio-iommu support for x86/ACPI.
Fixes, cleanups all over the place.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Mon 01 Nov 2021 07:36:22 PM EDT
# gpg:                using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg:                issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>" [full]

* remotes/mst/tags/for_upstream:
  hw/i386: fix vmmouse registration
  pci: Export pci_for_each_device_under_bus*()
  pci: Define pci_bus_dev_fn/pci_bus_fn/pci_bus_ret_fn
  hw/i386/pc: Allow instantiating a virtio-iommu device
  hw/i386/pc: Move IOMMU singleton into PCMachineState
  hw/i386/pc: Remove x86_iommu_get_type()
  hw/acpi: Add VIOT table
  vhost-vdpa: Set discarding of RAM broken when initializing the backend
  qtest: fix 'expression is always false' build failure in qtest_has_accel()

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

24 files changed, 239 insertions, 109 deletions

diff --git a/hw/acpi/Kconfig b/hw/acpi/Kconfig
index 3b5e118..622b0b5 100644
--- a/hw/acpi/Kconfig
+++ b/hw/acpi/Kconfig
@@ -51,6 +51,10 @@ config ACPI_VMGENID
     default y
     depends on PC
 
+config ACPI_VIOT
+    bool
+    depends on ACPI
+
 config ACPI_HW_REDUCED
     bool
     select ACPI
diff --git a/hw/acpi/meson.build b/hw/acpi/meson.build
index 7d8c0eb..adf6347 100644
--- a/hw/acpi/meson.build
+++ b/hw/acpi/meson.build
@@ -20,6 +20,7 @@ acpi_ss.add(when: 'CONFIG_ACPI_APEI', if_true: files('ghes.c'), if_false: files(
 acpi_ss.add(when: 'CONFIG_ACPI_PIIX4', if_true: files('piix4.c'))
 acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_true: files('pcihp.c'))
 acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_false: files('acpi-pci-hotplug-stub.c'))
+acpi_ss.add(when: 'CONFIG_ACPI_VIOT', if_true: files('viot.c'))
 acpi_ss.add(when: 'CONFIG_ACPI_X86_ICH', if_true: files('ich9.c', 'tco.c'))
 acpi_ss.add(when: 'CONFIG_IPMI', if_true: files('ipmi.c'), if_false: files('ipmi-stub.c'))
 acpi_ss.add(when: 'CONFIG_PC', if_false: files('acpi-x86-stub.c'))
diff --git a/hw/acpi/viot.c b/hw/acpi/viot.c
new file mode 100644
index 0000000..c1af752
--- /dev/null
+++ b/hw/acpi/viot.c
@@ -0,0 +1,114 @@
+/*
+ * ACPI Virtual I/O Translation table implementation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include "qemu/osdep.h"
+#include "hw/acpi/acpi.h"
+#include "hw/acpi/aml-build.h"
+#include "hw/acpi/viot.h"
+#include "hw/pci/pci.h"
+#include "hw/pci/pci_host.h"
+
+struct viot_pci_ranges {
+    GArray *blob;
+    size_t count;
+    uint16_t output_node;
+};
+
+/* Build PCI range for a given PCI host bridge */
+static int build_pci_range_node(Object *obj, void *opaque)
+{
+    struct viot_pci_ranges *pci_ranges = opaque;
+    GArray *blob = pci_ranges->blob;
+
+    if (object_dynamic_cast(obj, TYPE_PCI_HOST_BRIDGE)) {
+        PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus;
+
+        if (bus && !pci_bus_bypass_iommu(bus)) {
+            int min_bus, max_bus;
+
+            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++;
+        }
+    }
+
+    return 0;
+}
+
+/*
+ * Generate a VIOT table with one PCI-based virtio-iommu that manages PCI
+ * endpoints.
+ *
+ * Defined in the ACPI Specification (Version TBD)
+ */
+void build_viot(MachineState *ms, GArray *table_data, BIOSLinker *linker,
+                uint16_t virtio_iommu_bdf, const char *oem_id,
+                const char *oem_table_id)
+{
+    /* The virtio-iommu node follows the 48-bytes header */
+    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),
+    };
+
+    /* Build the list of PCI ranges that this viommu manages */
+    object_child_foreach_recursive(OBJECT(ms), build_pci_range_node,
+                                   &pci_ranges);
+
+    /* ACPI table header */
+    acpi_table_begin(&table, table_data);
+    /* Node count */
+    build_append_int_noprefix(table_data, pci_ranges.count + 1, 2);
+    /* Node offset */
+    build_append_int_noprefix(table_data, viommu_off, 2);
+    /* Reserved */
+    build_append_int_noprefix(table_data, 0, 8);
+
+    /* Virtio-iommu node */
+    /* Type */
+    build_append_int_noprefix(table_data, 3 /* virtio-pci IOMMU */, 1);
+    /* Reserved */
+    build_append_int_noprefix(table_data, 0, 1);
+    /* Length */
+    build_append_int_noprefix(table_data, 16, 2);
+    /* PCI Segment */
+    build_append_int_noprefix(table_data, 0, 2);
+    /* PCI BDF number */
+    build_append_int_noprefix(table_data, virtio_iommu_bdf, 2);
+    /* Reserved */
+    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);
+
+    acpi_table_end(linker, &table);
+}
+
diff --git a/hw/acpi/viot.h b/hw/acpi/viot.h
new file mode 100644
index 0000000..9fe565b
--- /dev/null
+++ b/hw/acpi/viot.h
@@ -0,0 +1,13 @@
+/*
+ * ACPI Virtual I/O Translation Table implementation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef VIOT_H
+#define VIOT_H
+
+void build_viot(MachineState *ms, GArray *table_data, BIOSLinker *linker,
+                uint16_t virtio_iommu_bdf, const char *oem_id,
+                const char *oem_table_id);
+
+#endif /* VIOT_H */
diff --git a/hw/i386/Kconfig b/hw/i386/Kconfig
index 962d2c9..d22ac4a 100644
--- a/hw/i386/Kconfig
+++ b/hw/i386/Kconfig
@@ -59,6 +59,7 @@ config PC_ACPI
     select ACPI_X86
     select ACPI_CPU_HOTPLUG
     select ACPI_MEMORY_HOTPLUG
+    select ACPI_VIOT
     select SMBUS_EEPROM
     select PFLASH_CFI01
     depends on ACPI_SMBUS
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 81418b7..a3ad6ab 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -68,9 +68,11 @@
 #include "qom/qom-qobject.h"
 #include "hw/i386/amd_iommu.h"
 #include "hw/i386/intel_iommu.h"
+#include "hw/virtio/virtio-iommu.h"
 
 #include "hw/acpi/ipmi.h"
 #include "hw/acpi/hmat.h"
+#include "hw/acpi/viot.h"
 
 /* These are used to size the ACPI tables for -M pc-i440fx-1.7 and
  * -M pc-i440fx-2.0.  Even if the actual amount of AML generated grows
@@ -2132,8 +2134,7 @@ dmar_host_bridges(Object *obj, void *opaque)
         PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus;
 
         if (bus && !pci_bus_bypass_iommu(bus)) {
-            pci_for_each_device(bus, pci_bus_num(bus), insert_scope,
-                                scope_blob);
+            pci_for_each_device_under_bus(bus, insert_scope, scope_blob);
         }
     }
 
@@ -2339,7 +2340,7 @@ ivrs_host_bridges(Object *obj, void *opaque)
         PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus;
 
         if (bus && !pci_bus_bypass_iommu(bus)) {
-            pci_for_each_device(bus, pci_bus_num(bus), insert_ivhd, ivhd_blob);
+            pci_for_each_device_under_bus(bus, insert_ivhd, ivhd_blob);
         }
     }
 
@@ -2488,6 +2489,7 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
     PCMachineState *pcms = PC_MACHINE(machine);
     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
     X86MachineState *x86ms = X86_MACHINE(machine);
+    DeviceState *iommu = pcms->iommu;
     GArray *table_offsets;
     unsigned facs, dsdt, rsdt, fadt;
     AcpiPmInfo pm;
@@ -2604,17 +2606,20 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
         build_mcfg(tables_blob, tables->linker, &mcfg, x86ms->oem_id,
                    x86ms->oem_table_id);
     }
-    if (x86_iommu_get_default()) {
-        IommuType IOMMUType = x86_iommu_get_type();
-        if (IOMMUType == TYPE_AMD) {
-            acpi_add_table(table_offsets, tables_blob);
-            build_amd_iommu(tables_blob, tables->linker, x86ms->oem_id,
-                            x86ms->oem_table_id);
-        } else if (IOMMUType == TYPE_INTEL) {
-            acpi_add_table(table_offsets, tables_blob);
-            build_dmar_q35(tables_blob, tables->linker, x86ms->oem_id,
-                           x86ms->oem_table_id);
-        }
+    if (object_dynamic_cast(OBJECT(iommu), TYPE_AMD_IOMMU_DEVICE)) {
+        acpi_add_table(table_offsets, tables_blob);
+        build_amd_iommu(tables_blob, tables->linker, x86ms->oem_id,
+                        x86ms->oem_table_id);
+    } else if (object_dynamic_cast(OBJECT(iommu), TYPE_INTEL_IOMMU_DEVICE)) {
+        acpi_add_table(table_offsets, tables_blob);
+        build_dmar_q35(tables_blob, tables->linker, x86ms->oem_id,
+                       x86ms->oem_table_id);
+    } else if (object_dynamic_cast(OBJECT(iommu), TYPE_VIRTIO_IOMMU_PCI)) {
+        PCIDevice *pdev = PCI_DEVICE(iommu);
+
+        acpi_add_table(table_offsets, tables_blob);
+        build_viot(machine, tables_blob, tables->linker, pci_get_bdf(pdev),
+                   x86ms->oem_id, x86ms->oem_table_id);
     }
     if (machine->nvdimms_state->is_enabled) {
         nvdimm_build_acpi(table_offsets, tables_blob, tables->linker,
diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c
index 9242a0d..91fe34a 100644
--- a/hw/i386/amd_iommu.c
+++ b/hw/i386/amd_iommu.c
@@ -1538,7 +1538,6 @@ static void amdvi_sysbus_realize(DeviceState *dev, Error **errp)
 {
     int ret = 0;
     AMDVIState *s = AMD_IOMMU_DEVICE(dev);
-    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);
     MachineState *ms = MACHINE(qdev_get_machine());
     PCMachineState *pcms = PC_MACHINE(ms);
     X86MachineState *x86ms = X86_MACHINE(ms);
@@ -1548,7 +1547,6 @@ static void amdvi_sysbus_realize(DeviceState *dev, Error **errp)
                                      amdvi_uint64_equal, g_free, g_free);
 
     /* This device should take care of IOMMU PCI properties */
-    x86_iommu->type = TYPE_AMD;
     if (!qdev_realize(DEVICE(&s->pci), &bus->qbus, errp)) {
         return;
     }
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 75f0755..c27b200 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -3806,9 +3806,6 @@ static void vtd_realize(DeviceState *dev, Error **errp)
     X86MachineState *x86ms = X86_MACHINE(ms);
     PCIBus *bus = pcms->bus;
     IntelIOMMUState *s = INTEL_IOMMU_DEVICE(dev);
-    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);
-
-    x86_iommu->type = TYPE_INTEL;
 
     if (!vtd_decide_config(s, errp)) {
         return;
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 86223ac..e99017e 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -83,6 +83,7 @@
 #include "hw/i386/intel_iommu.h"
 #include "hw/net/ne2000-isa.h"
 #include "standard-headers/asm-x86/bootparam.h"
+#include "hw/virtio/virtio-iommu.h"
 #include "hw/virtio/virtio-pmem-pci.h"
 #include "hw/virtio/virtio-mem-pci.h"
 #include "hw/mem/memory-device.h"
@@ -1330,6 +1331,27 @@ static void pc_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI) ||
                object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_MEM_PCI)) {
         pc_virtio_md_pci_pre_plug(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_IOMMU_PCI)) {
+        /* Declare the APIC range as the reserved MSI region */
+        char *resv_prop_str = g_strdup_printf("0xfee00000:0xfeefffff:%d",
+                                              VIRTIO_IOMMU_RESV_MEM_T_MSI);
+
+        object_property_set_uint(OBJECT(dev), "len-reserved-regions", 1, errp);
+        object_property_set_str(OBJECT(dev), "reserved-regions[0]",
+                                resv_prop_str, errp);
+        g_free(resv_prop_str);
+    }
+
+    if (object_dynamic_cast(OBJECT(dev), TYPE_X86_IOMMU_DEVICE) ||
+        object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_IOMMU_PCI)) {
+        PCMachineState *pcms = PC_MACHINE(hotplug_dev);
+
+        if (pcms->iommu) {
+            error_setg(errp, "QEMU does not support multiple vIOMMUs "
+                       "for x86 yet.");
+            return;
+        }
+        pcms->iommu = dev;
     }
 }
 
@@ -1384,7 +1406,9 @@ static HotplugHandler *pc_get_hotplug_handler(MachineState *machine,
     if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM) ||
         object_dynamic_cast(OBJECT(dev), TYPE_CPU) ||
         object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI) ||
-        object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_MEM_PCI)) {
+        object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_MEM_PCI) ||
+        object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_IOMMU_PCI) ||
+        object_dynamic_cast(OBJECT(dev), TYPE_X86_IOMMU_DEVICE)) {
         return HOTPLUG_HANDLER(machine);
     }
 
diff --git a/hw/i386/vmmouse.c b/hw/i386/vmmouse.c
index df4798f..3d66368 100644
--- a/hw/i386/vmmouse.c
+++ b/hw/i386/vmmouse.c
@@ -158,6 +158,7 @@ static void vmmouse_read_id(VMMouseState *s)
 
     s->queue[s->nb_queue++] = VMMOUSE_VERSION;
     s->status = 0;
+    vmmouse_update_handler(s, s->absolute);
 }
 
 static void vmmouse_request_relative(VMMouseState *s)
diff --git a/hw/i386/x86-iommu-stub.c b/hw/i386/x86-iommu-stub.c
index c5ba077..781b5ff 100644
--- a/hw/i386/x86-iommu-stub.c
+++ b/hw/i386/x86-iommu-stub.c
@@ -36,8 +36,3 @@ bool x86_iommu_ir_supported(X86IOMMUState *s)
 {
     return false;
 }
-
-IommuType x86_iommu_get_type(void)
-{
-    abort();
-}
diff --git a/hw/i386/x86-iommu.c b/hw/i386/x86-iommu.c
index 86ad039..01d1132 100644
--- a/hw/i386/x86-iommu.c
+++ b/hw/i386/x86-iommu.c
@@ -77,30 +77,17 @@ void x86_iommu_irq_to_msi_message(X86IOMMUIrq *irq, MSIMessage *msg_out)
     msg_out->data = msg.msi_data;
 }
 
-/* Default X86 IOMMU device */
-static X86IOMMUState *x86_iommu_default = NULL;
-
-static void x86_iommu_set_default(X86IOMMUState *x86_iommu)
-{
-    assert(x86_iommu);
-
-    if (x86_iommu_default) {
-        error_report("QEMU does not support multiple vIOMMUs "
-                     "for x86 yet.");
-        exit(1);
-    }
-
-    x86_iommu_default = x86_iommu;
-}
-
 X86IOMMUState *x86_iommu_get_default(void)
 {
-    return x86_iommu_default;
-}
+    MachineState *ms = MACHINE(qdev_get_machine());
+    PCMachineState *pcms =
+        PC_MACHINE(object_dynamic_cast(OBJECT(ms), TYPE_PC_MACHINE));
 
-IommuType x86_iommu_get_type(void)
-{
-    return x86_iommu_default->type;
+    if (pcms &&
+        object_dynamic_cast(OBJECT(pcms->iommu), TYPE_X86_IOMMU_DEVICE)) {
+        return X86_IOMMU_DEVICE(pcms->iommu);
+    }
+    return NULL;
 }
 
 static void x86_iommu_realize(DeviceState *dev, Error **errp)
@@ -136,8 +123,6 @@ static void x86_iommu_realize(DeviceState *dev, Error **errp)
     if (x86_class->realize) {
         x86_class->realize(dev, errp);
     }
-
-    x86_iommu_set_default(X86_IOMMU_DEVICE(dev));
 }
 
 static Property x86_iommu_properties[] = {
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 186758e..4a84e47 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -1654,11 +1654,9 @@ static const pci_class_desc pci_class_descriptions[] =
     { 0, NULL}
 };
 
-static void pci_for_each_device_under_bus_reverse(PCIBus *bus,
-                                                  void (*fn)(PCIBus *b,
-                                                             PCIDevice *d,
-                                                             void *opaque),
-                                                  void *opaque)
+void pci_for_each_device_under_bus_reverse(PCIBus *bus,
+                                           pci_bus_dev_fn fn,
+                                           void *opaque)
 {
     PCIDevice *d;
     int devfn;
@@ -1672,8 +1670,7 @@ static void pci_for_each_device_under_bus_reverse(PCIBus *bus,
 }
 
 void pci_for_each_device_reverse(PCIBus *bus, int bus_num,
-                         void (*fn)(PCIBus *b, PCIDevice *d, void *opaque),
-                         void *opaque)
+                                 pci_bus_dev_fn fn, void *opaque)
 {
     bus = pci_find_bus_nr(bus, bus_num);
 
@@ -1682,10 +1679,8 @@ void pci_for_each_device_reverse(PCIBus *bus, int bus_num,
     }
 }
 
-static void pci_for_each_device_under_bus(PCIBus *bus,
-                                          void (*fn)(PCIBus *b, PCIDevice *d,
-                                                     void *opaque),
-                                          void *opaque)
+void pci_for_each_device_under_bus(PCIBus *bus,
+                                   pci_bus_dev_fn fn, void *opaque)
 {
     PCIDevice *d;
     int devfn;
@@ -1699,8 +1694,7 @@ static void pci_for_each_device_under_bus(PCIBus *bus,
 }
 
 void pci_for_each_device(PCIBus *bus, int bus_num,
-                         void (*fn)(PCIBus *b, PCIDevice *d, void *opaque),
-                         void *opaque)
+                         pci_bus_dev_fn fn, void *opaque)
 {
     bus = pci_find_bus_nr(bus, bus_num);
 
@@ -2078,10 +2072,8 @@ static PCIBus *pci_find_bus_nr(PCIBus *bus, int bus_num)
     return NULL;
 }
 
-void pci_for_each_bus_depth_first(PCIBus *bus,
-                                  void *(*begin)(PCIBus *bus, void *parent_state),
-                                  void (*end)(PCIBus *bus, void *state),
-                                  void *parent_state)
+void pci_for_each_bus_depth_first(PCIBus *bus, pci_bus_ret_fn begin,
+                                  pci_bus_fn end, void *parent_state)
 {
     PCIBus *sec;
     void *state;
diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
index 6e95d82..914a9bf 100644
--- a/hw/pci/pcie.c
+++ b/hw/pci/pcie.c
@@ -694,9 +694,7 @@ void pcie_cap_slot_write_config(PCIDevice *dev,
         (!(old_slt_ctl & PCI_EXP_SLTCTL_PCC) ||
         (old_slt_ctl & PCI_EXP_SLTCTL_PIC_OFF) != PCI_EXP_SLTCTL_PIC_OFF)) {
         PCIBus *sec_bus = pci_bridge_get_sec_bus(PCI_BRIDGE(dev));
-        pci_for_each_device(sec_bus, pci_bus_num(sec_bus),
-                            pcie_unplug_device, NULL);
-
+        pci_for_each_device_under_bus(sec_bus, pcie_unplug_device, NULL);
         pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,
                                      PCI_EXP_SLTSTA_PDS);
         if (dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA ||
diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
index 7430bd6..5bfd4aa 100644
--- a/hw/ppc/spapr_pci.c
+++ b/hw/ppc/spapr_pci.c
@@ -1317,8 +1317,7 @@ static int spapr_dt_pci_bus(SpaprPhbState *sphb, PCIBus *bus,
                           RESOURCE_CELLS_SIZE));
 
     assert(bus);
-    pci_for_each_device_reverse(bus, pci_bus_num(bus),
-                                spapr_dt_pci_device_cb, &cbinfo);
+    pci_for_each_device_under_bus_reverse(bus, spapr_dt_pci_device_cb, &cbinfo);
     if (cbinfo.err) {
         return cbinfo.err;
     }
@@ -2306,8 +2305,8 @@ static void spapr_phb_pci_enumerate_bridge(PCIBus *bus, PCIDevice *pdev,
         return;
     }
 
-    pci_for_each_device(sec_bus, pci_bus_num(sec_bus),
-                        spapr_phb_pci_enumerate_bridge, bus_no);
+    pci_for_each_device_under_bus(sec_bus, spapr_phb_pci_enumerate_bridge,
+                                  bus_no);
     pci_default_write_config(pdev, PCI_SUBORDINATE_BUS, *bus_no, 1);
 }
 
@@ -2316,9 +2315,8 @@ static void spapr_phb_pci_enumerate(SpaprPhbState *phb)
     PCIBus *bus = PCI_HOST_BRIDGE(phb)->bus;
     unsigned int bus_no = 0;
 
-    pci_for_each_device(bus, pci_bus_num(bus),
-                        spapr_phb_pci_enumerate_bridge,
-                        &bus_no);
+    pci_for_each_device_under_bus(bus, spapr_phb_pci_enumerate_bridge,
+                                  &bus_no);
 
 }
 
diff --git a/hw/ppc/spapr_pci_nvlink2.c b/hw/ppc/spapr_pci_nvlink2.c
index 8ef9b40..7fb0cf4 100644
--- a/hw/ppc/spapr_pci_nvlink2.c
+++ b/hw/ppc/spapr_pci_nvlink2.c
@@ -164,8 +164,7 @@ static void spapr_phb_pci_collect_nvgpu(PCIBus *bus, PCIDevice *pdev,
         return;
     }
 
-    pci_for_each_device(sec_bus, pci_bus_num(sec_bus),
-                        spapr_phb_pci_collect_nvgpu, opaque);
+    pci_for_each_device_under_bus(sec_bus, spapr_phb_pci_collect_nvgpu, opaque);
 }
 
 void spapr_phb_nvgpu_setup(SpaprPhbState *sphb, Error **errp)
@@ -183,8 +182,8 @@ void spapr_phb_nvgpu_setup(SpaprPhbState *sphb, Error **errp)
     sphb->nvgpus->nv2_atsd_current = sphb->nv2_atsd_win_addr;
 
     bus = PCI_HOST_BRIDGE(sphb)->bus;
-    pci_for_each_device(bus, pci_bus_num(bus),
-                        spapr_phb_pci_collect_nvgpu, sphb->nvgpus);
+    pci_for_each_device_under_bus(bus, spapr_phb_pci_collect_nvgpu,
+                                  sphb->nvgpus);
 
     if (sphb->nvgpus->err) {
         error_propagate(errp, sphb->nvgpus->err);
diff --git a/hw/ppc/spapr_pci_vfio.c b/hw/ppc/spapr_pci_vfio.c
index f3b37df..2a76b4e 100644
--- a/hw/ppc/spapr_pci_vfio.c
+++ b/hw/ppc/spapr_pci_vfio.c
@@ -164,8 +164,8 @@ static void spapr_phb_vfio_eeh_clear_dev_msix(PCIBus *bus,
 
 static void spapr_phb_vfio_eeh_clear_bus_msix(PCIBus *bus, void *opaque)
 {
-       pci_for_each_device(bus, pci_bus_num(bus),
-                           spapr_phb_vfio_eeh_clear_dev_msix, NULL);
+       pci_for_each_device_under_bus(bus, spapr_phb_vfio_eeh_clear_dev_msix,
+                                     NULL);
 }
 
 static void spapr_phb_vfio_eeh_pre_reset(SpaprPhbState *sphb)
diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index 6fafffb..1b51a72 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -1163,8 +1163,7 @@ static void s390_pci_enumerate_bridge(PCIBus *bus, PCIDevice *pdev,
     }
 
     /* Assign numbers to all child bridges. The last is the highest number. */
-    pci_for_each_device(sec_bus, pci_bus_num(sec_bus),
-                        s390_pci_enumerate_bridge, s);
+    pci_for_each_device_under_bus(sec_bus, s390_pci_enumerate_bridge, s);
     pci_default_write_config(pdev, PCI_SUBORDINATE_BUS, s->bus_no, 1);
 }
 
@@ -1193,7 +1192,7 @@ static void s390_pcihost_reset(DeviceState *dev)
      * on every system reset, we also have to reassign numbers.
      */
     s->bus_no = 0;
-    pci_for_each_device(bus, pci_bus_num(bus), s390_pci_enumerate_bridge, s);
+    pci_for_each_device_under_bus(bus, s390_pci_enumerate_bridge, s);
 }
 
 static void s390_pcihost_class_init(ObjectClass *klass, void *data)
diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 12661fd..0d80514 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -331,6 +331,17 @@ static int vhost_vdpa_init(struct vhost_dev *dev, void *opaque, Error **errp)
     struct vhost_vdpa *v;
     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_VDPA);
     trace_vhost_vdpa_init(dev, opaque);
+    int ret;
+
+    /*
+     * Similar to VFIO, we end up pinning all guest memory and have to
+     * disable discarding of RAM.
+     */
+    ret = ram_block_discard_disable(true);
+    if (ret) {
+        error_report("Cannot set discarding of RAM broken");
+        return ret;
+    }
 
     v = opaque;
     v->dev = dev;
@@ -442,6 +453,8 @@ static int vhost_vdpa_cleanup(struct vhost_dev *dev)
     memory_listener_unregister(&v->listener);
 
     dev->opaque = NULL;
+    ram_block_discard_disable(false);
+
     return 0;
 }
 
diff --git a/hw/xen/xen_pt.c b/hw/xen/xen_pt.c
index ca0a981..027190f 100644
--- a/hw/xen/xen_pt.c
+++ b/hw/xen/xen_pt.c
@@ -615,8 +615,8 @@ static void xen_pt_region_update(XenPCIPassthroughState *s,
     }
 
     args.type = d->io_regions[bar].type;
-    pci_for_each_device(pci_get_bus(d), pci_dev_bus_num(d),
-                        xen_pt_check_bar_overlap, &args);
+    pci_for_each_device_under_bus(pci_get_bus(d),
+                                  xen_pt_check_bar_overlap, &args);
     if (args.rc) {
         XEN_PT_WARN(d, "Region: %d (addr: 0x%"FMT_PCIBUS
                     ", len: 0x%"FMT_PCIBUS") is overlapped.\n",
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 11426e2..b72e5bf 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -35,6 +35,7 @@ typedef struct PCMachineState {
     I2CBus *smbus;
     PFlashCFI01 *flash[2];
     ISADevice *pcspk;
+    DeviceState *iommu;
 
     /* Configuration options: */
     uint64_t max_ram_below_4g;
diff --git a/include/hw/i386/x86-iommu.h b/include/hw/i386/x86-iommu.h
index 9de92d3..5ba0c05 100644
--- a/include/hw/i386/x86-iommu.h
+++ b/include/hw/i386/x86-iommu.h
@@ -33,12 +33,6 @@ OBJECT_DECLARE_TYPE(X86IOMMUState, X86IOMMUClass, X86_IOMMU_DEVICE)
 typedef struct X86IOMMUIrq X86IOMMUIrq;
 typedef struct X86IOMMU_MSIMessage X86IOMMU_MSIMessage;
 
-typedef enum IommuType {
-    TYPE_INTEL,
-    TYPE_AMD,
-    TYPE_NONE
-} IommuType;
-
 struct X86IOMMUClass {
     SysBusDeviceClass parent;
     /* Intel/AMD specific realize() hook */
@@ -71,7 +65,6 @@ struct X86IOMMUState {
     OnOffAuto intr_supported;   /* Whether vIOMMU supports IR */
     bool dt_supported;          /* Whether vIOMMU supports DT */
     bool pt_supported;          /* Whether vIOMMU supports pass-through */
-    IommuType type;             /* IOMMU type - AMD/Intel     */
     QLIST_HEAD(, IEC_Notifier) iec_notifiers; /* IEC notify list */
 };
 
@@ -140,11 +133,6 @@ struct X86IOMMU_MSIMessage {
  */
 X86IOMMUState *x86_iommu_get_default(void);
 
-/*
- * x86_iommu_get_type - get IOMMU type
- */
-IommuType x86_iommu_get_type(void);
-
 /**
  * x86_iommu_iec_register_notifier - register IEC (Interrupt Entry
  *                                   Cache) notifiers
diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index 7fc9013..5c4016b 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -401,6 +401,10 @@ typedef PCIINTxRoute (*pci_route_irq_fn)(void *opaque, int pin);
 OBJECT_DECLARE_TYPE(PCIBus, PCIBusClass, PCI_BUS)
 #define TYPE_PCIE_BUS "PCIE"
 
+typedef void (*pci_bus_dev_fn)(PCIBus *b, PCIDevice *d, void *opaque);
+typedef void (*pci_bus_fn)(PCIBus *b, void *opaque);
+typedef void *(*pci_bus_ret_fn)(PCIBus *b, void *opaque);
+
 bool pci_bus_is_express(PCIBus *bus);
 
 void pci_root_bus_init(PCIBus *bus, size_t bus_size, DeviceState *parent,
@@ -458,23 +462,23 @@ static inline int pci_dev_bus_num(const PCIDevice *dev)
 
 int pci_bus_numa_node(PCIBus *bus);
 void pci_for_each_device(PCIBus *bus, int bus_num,
-                         void (*fn)(PCIBus *bus, PCIDevice *d, void *opaque),
+                         pci_bus_dev_fn fn,
                          void *opaque);
 void pci_for_each_device_reverse(PCIBus *bus, int bus_num,
-                                 void (*fn)(PCIBus *bus, PCIDevice *d,
-                                            void *opaque),
+                                 pci_bus_dev_fn fn,
                                  void *opaque);
-void pci_for_each_bus_depth_first(PCIBus *bus,
-                                  void *(*begin)(PCIBus *bus, void *parent_state),
-                                  void (*end)(PCIBus *bus, void *state),
-                                  void *parent_state);
+void pci_for_each_device_under_bus(PCIBus *bus,
+                                   pci_bus_dev_fn fn, void *opaque);
+void pci_for_each_device_under_bus_reverse(PCIBus *bus,
+                                           pci_bus_dev_fn fn,
+                                           void *opaque);
+void pci_for_each_bus_depth_first(PCIBus *bus, pci_bus_ret_fn begin,
+                                  pci_bus_fn end, void *parent_state);
 PCIDevice *pci_get_function_0(PCIDevice *pci_dev);
 
 /* Use this wrapper when specific scan order is not required. */
 static inline
-void pci_for_each_bus(PCIBus *bus,
-                      void (*fn)(PCIBus *bus, void *opaque),
-                      void *opaque)
+void pci_for_each_bus(PCIBus *bus, pci_bus_fn fn, void *opaque)
 {
     pci_for_each_bus_depth_first(bus, NULL, fn, opaque);
 }
diff --git a/meson.build b/meson.build
index bc918fb..26c5812 100644
--- a/meson.build
+++ b/meson.build
@@ -75,7 +75,7 @@ else
   kvm_targets = []
 endif
 
-kvm_targets_c = ''
+kvm_targets_c = '""'
 if not get_option('kvm').disabled() and targetos == 'linux'
   kvm_targets_c = '"' + '" ,"'.join(kvm_targets) + '"'
 endif