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

pc, pci, virtio: new features, cleanups, fixes

- interrupt remapping for intel iommus
- a bunch of virtio cleanups
- fixes all over the place

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

# gpg: Signature made Thu 21 Jul 2016 18:49:30 BST
# gpg:                using RSA key 0x281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (57 commits)
  intel_iommu: avoid unnamed fields
  virtio: Update migration docs
  virtio-gpu: Wrap in vmstate
  virtio-gpu: Use migrate_add_blocker for virgl migration blocking
  virtio-input: Wrap in vmstate
  9pfs: Wrap in vmstate
  virtio-serial: Wrap in vmstate
  virtio-net: Wrap in vmstate
  virtio-balloon: Wrap in vmstate
  virtio-rng: Wrap in vmstate
  virtio-blk: Wrap in vmstate
  virtio-scsi: Wrap in vmstate
  virtio: Migration helper function and macro
  virtio-serial: Remove old migration version support
  virtio-net: Remove old migration version support
  virtio-scsi: Replace HandleOutput typedef
  Revert "mirror: Workaround for unexpected iohandler events during completion"
  virtio-scsi: Call virtio_add_queue_aio
  virtio-blk: Call virtio_add_queue_aio
  virtio: Introduce virtio_add_queue_aio
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

8 files changed, 646 insertions, 30 deletions

diff --git a/hw/i386/Makefile.objs b/hw/i386/Makefile.objs
index b52d5b8..90e94ff 100644
--- a/hw/i386/Makefile.objs
+++ b/hw/i386/Makefile.objs
@@ -2,7 +2,7 @@ obj-$(CONFIG_KVM) += kvm/
 obj-y += multiboot.o
 obj-y += pc.o pc_piix.o pc_q35.o
 obj-y += pc_sysfw.o
-obj-y += intel_iommu.o
+obj-y += x86-iommu.o intel_iommu.o
 obj-$(CONFIG_XEN) += ../xenpv/ xen/
 
 obj-y += kvmvapic.o
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index fbba461..77c40d9 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -52,13 +52,14 @@
 #include "hw/i386/ich9.h"
 #include "hw/pci/pci_bus.h"
 #include "hw/pci-host/q35.h"
-#include "hw/i386/intel_iommu.h"
+#include "hw/i386/x86-iommu.h"
 #include "hw/timer/hpet.h"
 
 #include "hw/acpi/aml-build.h"
 
 #include "qapi/qmp/qint.h"
 #include "qom/qom-qobject.h"
+#include "hw/i386/x86-iommu.h"
 
 #include "hw/acpi/ipmi.h"
 
@@ -80,6 +81,9 @@
 #define ACPI_BUILD_DPRINTF(fmt, ...)
 #endif
 
+/* Default IOAPIC ID */
+#define ACPI_BUILD_IOAPIC_ID 0x0
+
 typedef struct AcpiMcfgInfo {
     uint64_t mcfg_base;
     uint32_t mcfg_size;
@@ -383,7 +387,6 @@ build_madt(GArray *table_data, BIOSLinker *linker, PCMachineState *pcms)
     io_apic = acpi_data_push(table_data, sizeof *io_apic);
     io_apic->type = ACPI_APIC_IO;
     io_apic->length = sizeof(*io_apic);
-#define ACPI_BUILD_IOAPIC_ID 0x0
     io_apic->io_apic_id = ACPI_BUILD_IOAPIC_ID;
     io_apic->address = cpu_to_le32(IO_APIC_DEFAULT_ADDRESS);
     io_apic->interrupt = cpu_to_le32(0);
@@ -2454,6 +2457,10 @@ build_mcfg_q35(GArray *table_data, BIOSLinker *linker, AcpiMcfgInfo *info)
     build_header(linker, table_data, (void *)mcfg, sig, len, 1, NULL, NULL);
 }
 
+/*
+ * VT-d spec 8.1 DMA Remapping Reporting Structure
+ * (version Oct. 2014 or later)
+ */
 static void
 build_dmar_q35(GArray *table_data, BIOSLinker *linker)
 {
@@ -2461,19 +2468,38 @@ build_dmar_q35(GArray *table_data, BIOSLinker *linker)
 
     AcpiTableDmar *dmar;
     AcpiDmarHardwareUnit *drhd;
+    uint8_t dmar_flags = 0;
+    X86IOMMUState *iommu = x86_iommu_get_default();
+    AcpiDmarDeviceScope *scope = NULL;
+    /* Root complex IOAPIC use one path[0] only */
+    size_t ioapic_scope_size = sizeof(*scope) + sizeof(scope->path[0]);
+
+    assert(iommu);
+    if (iommu->intr_supported) {
+        dmar_flags |= 0x1;      /* Flags: 0x1: INT_REMAP */
+    }
 
     dmar = acpi_data_push(table_data, sizeof(*dmar));
     dmar->host_address_width = VTD_HOST_ADDRESS_WIDTH - 1;
-    dmar->flags = 0;    /* No intr_remap for now */
+    dmar->flags = dmar_flags;
 
     /* DMAR Remapping Hardware Unit Definition structure */
-    drhd = acpi_data_push(table_data, sizeof(*drhd));
+    drhd = acpi_data_push(table_data, sizeof(*drhd) + ioapic_scope_size);
     drhd->type = cpu_to_le16(ACPI_DMAR_TYPE_HARDWARE_UNIT);
-    drhd->length = cpu_to_le16(sizeof(*drhd));   /* No device scope now */
+    drhd->length = cpu_to_le16(sizeof(*drhd) + ioapic_scope_size);
     drhd->flags = ACPI_DMAR_INCLUDE_PCI_ALL;
     drhd->pci_segment = cpu_to_le16(0);
     drhd->address = cpu_to_le64(Q35_HOST_BRIDGE_IOMMU_ADDR);
 
+    /* Scope definition for the root-complex IOAPIC. See VT-d spec
+     * 8.3.1 (version Oct. 2014 or later). */
+    scope = &drhd->scope[0];
+    scope->entry_type = 0x03;   /* Type: 0x03 for IOAPIC */
+    scope->length = ioapic_scope_size;
+    scope->enumeration_id = ACPI_BUILD_IOAPIC_ID;
+    scope->bus = Q35_PSEUDO_BUS_PLATFORM;
+    scope->path[0] = cpu_to_le16(Q35_PSEUDO_DEVFN_IOAPIC);
+
     build_header(linker, table_data, (void *)(table_data->data + dmar_start),
                  "DMAR", table_data->len - dmar_start, 1, NULL, NULL);
 }
@@ -2539,12 +2565,7 @@ static bool acpi_get_mcfg(AcpiMcfgInfo *mcfg)
 
 static bool acpi_has_iommu(void)
 {
-    bool ambiguous;
-    Object *intel_iommu;
-
-    intel_iommu = object_resolve_path_type("", TYPE_INTEL_IOMMU_DEVICE,
-                                           &ambiguous);
-    return intel_iommu && !ambiguous;
+    return !!x86_iommu_get_default();
 }
 
 static
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 464f2a0..28c31a2 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -20,18 +20,23 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/error-report.h"
 #include "hw/sysbus.h"
 #include "exec/address-spaces.h"
 #include "intel_iommu_internal.h"
 #include "hw/pci/pci.h"
 #include "hw/pci/pci_bus.h"
 #include "hw/i386/pc.h"
+#include "hw/boards.h"
+#include "hw/i386/x86-iommu.h"
+#include "hw/pci-host/q35.h"
+#include "sysemu/kvm.h"
 
 /*#define DEBUG_INTEL_IOMMU*/
 #ifdef DEBUG_INTEL_IOMMU
 enum {
     DEBUG_GENERAL, DEBUG_CSR, DEBUG_INV, DEBUG_MMU, DEBUG_FLOG,
-    DEBUG_CACHE,
+    DEBUG_CACHE, DEBUG_IR,
 };
 #define VTD_DBGBIT(x)   (1 << DEBUG_##x)
 static int vtd_dbgflags = VTD_DBGBIT(GENERAL) | VTD_DBGBIT(CSR);
@@ -192,7 +197,7 @@ static void vtd_reset_context_cache(IntelIOMMUState *s)
 
     VTD_DPRINTF(CACHE, "global context_cache_gen=1");
     while (g_hash_table_iter_next (&bus_it, NULL, (void**)&vtd_bus)) {
-        for (devfn_it = 0; devfn_it < VTD_PCI_DEVFN_MAX; ++devfn_it) {
+        for (devfn_it = 0; devfn_it < X86_IOMMU_PCI_DEVFN_MAX; ++devfn_it) {
             vtd_as = vtd_bus->dev_as[devfn_it];
             if (!vtd_as) {
                 continue;
@@ -901,6 +906,27 @@ static void vtd_root_table_setup(IntelIOMMUState *s)
                 (s->root_extended ? "(extended)" : ""));
 }
 
+static void vtd_iec_notify_all(IntelIOMMUState *s, bool global,
+                               uint32_t index, uint32_t mask)
+{
+    x86_iommu_iec_notify_all(X86_IOMMU_DEVICE(s), global, index, mask);
+}
+
+static void vtd_interrupt_remap_table_setup(IntelIOMMUState *s)
+{
+    uint64_t value = 0;
+    value = vtd_get_quad_raw(s, DMAR_IRTA_REG);
+    s->intr_size = 1UL << ((value & VTD_IRTA_SIZE_MASK) + 1);
+    s->intr_root = value & VTD_IRTA_ADDR_MASK;
+    s->intr_eime = value & VTD_IRTA_EIME;
+
+    /* Notify global invalidation */
+    vtd_iec_notify_all(s, true, 0, 0);
+
+    VTD_DPRINTF(CSR, "int remap table addr 0x%"PRIx64 " size %"PRIu32,
+                s->intr_root, s->intr_size);
+}
+
 static void vtd_context_global_invalidate(IntelIOMMUState *s)
 {
     s->context_cache_gen++;
@@ -964,7 +990,7 @@ static void vtd_context_device_invalidate(IntelIOMMUState *s,
     vtd_bus = vtd_find_as_from_bus_num(s, VTD_SID_TO_BUS(source_id));
     if (vtd_bus) {
         devfn = VTD_SID_TO_DEVFN(source_id);
-        for (devfn_it = 0; devfn_it < VTD_PCI_DEVFN_MAX; ++devfn_it) {
+        for (devfn_it = 0; devfn_it < X86_IOMMU_PCI_DEVFN_MAX; ++devfn_it) {
             vtd_as = vtd_bus->dev_as[devfn_it];
             if (vtd_as && ((devfn_it & mask) == (devfn & mask))) {
                 VTD_DPRINTF(INV, "invalidate context-cahce of devfn 0x%"PRIx16,
@@ -1139,6 +1165,16 @@ static void vtd_handle_gcmd_srtp(IntelIOMMUState *s)
     vtd_set_clear_mask_long(s, DMAR_GSTS_REG, 0, VTD_GSTS_RTPS);
 }
 
+/* Set Interrupt Remap Table Pointer */
+static void vtd_handle_gcmd_sirtp(IntelIOMMUState *s)
+{
+    VTD_DPRINTF(CSR, "set Interrupt Remap Table Pointer");
+
+    vtd_interrupt_remap_table_setup(s);
+    /* Ok - report back to driver */
+    vtd_set_clear_mask_long(s, DMAR_GSTS_REG, 0, VTD_GSTS_IRTPS);
+}
+
 /* Handle Translation Enable/Disable */
 static void vtd_handle_gcmd_te(IntelIOMMUState *s, bool en)
 {
@@ -1158,6 +1194,22 @@ static void vtd_handle_gcmd_te(IntelIOMMUState *s, bool en)
     }
 }
 
+/* Handle Interrupt Remap Enable/Disable */
+static void vtd_handle_gcmd_ire(IntelIOMMUState *s, bool en)
+{
+    VTD_DPRINTF(CSR, "Interrupt Remap Enable %s", (en ? "on" : "off"));
+
+    if (en) {
+        s->intr_enabled = true;
+        /* Ok - report back to driver */
+        vtd_set_clear_mask_long(s, DMAR_GSTS_REG, 0, VTD_GSTS_IRES);
+    } else {
+        s->intr_enabled = false;
+        /* Ok - report back to driver */
+        vtd_set_clear_mask_long(s, DMAR_GSTS_REG, VTD_GSTS_IRES, 0);
+    }
+}
+
 /* Handle write to Global Command Register */
 static void vtd_handle_gcmd_write(IntelIOMMUState *s)
 {
@@ -1178,6 +1230,14 @@ static void vtd_handle_gcmd_write(IntelIOMMUState *s)
         /* Queued Invalidation Enable */
         vtd_handle_gcmd_qie(s, val & VTD_GCMD_QIE);
     }
+    if (val & VTD_GCMD_SIRTP) {
+        /* Set/update the interrupt remapping root-table pointer */
+        vtd_handle_gcmd_sirtp(s);
+    }
+    if (changed & VTD_GCMD_IRE) {
+        /* Interrupt remap enable/disable */
+        vtd_handle_gcmd_ire(s, val & VTD_GCMD_IRE);
+    }
 }
 
 /* Handle write to Context Command Register */
@@ -1363,6 +1423,21 @@ static bool vtd_process_iotlb_desc(IntelIOMMUState *s, VTDInvDesc *inv_desc)
     return true;
 }
 
+static bool vtd_process_inv_iec_desc(IntelIOMMUState *s,
+                                     VTDInvDesc *inv_desc)
+{
+    VTD_DPRINTF(INV, "inv ir glob %d index %d mask %d",
+                inv_desc->iec.granularity,
+                inv_desc->iec.index,
+                inv_desc->iec.index_mask);
+
+    vtd_iec_notify_all(s, !inv_desc->iec.granularity,
+                       inv_desc->iec.index,
+                       inv_desc->iec.index_mask);
+
+    return true;
+}
+
 static bool vtd_process_inv_desc(IntelIOMMUState *s)
 {
     VTDInvDesc inv_desc;
@@ -1402,6 +1477,15 @@ static bool vtd_process_inv_desc(IntelIOMMUState *s)
         }
         break;
 
+    case VTD_INV_DESC_IEC:
+        VTD_DPRINTF(INV, "Invalidation Interrupt Entry Cache "
+                    "Descriptor hi 0x%"PRIx64 " lo 0x%"PRIx64,
+                    inv_desc.hi, inv_desc.lo);
+        if (!vtd_process_inv_iec_desc(s, &inv_desc)) {
+            return false;
+        }
+        break;
+
     default:
         VTD_DPRINTF(GENERAL, "error: unkonw Invalidation Descriptor type "
                     "hi 0x%"PRIx64 " lo 0x%"PRIx64 " type %"PRIu8,
@@ -1830,6 +1914,23 @@ static void vtd_mem_write(void *opaque, hwaddr addr,
         vtd_update_fsts_ppf(s);
         break;
 
+    case DMAR_IRTA_REG:
+        VTD_DPRINTF(IR, "DMAR_IRTA_REG write addr 0x%"PRIx64
+                    ", size %d, val 0x%"PRIx64, addr, size, val);
+        if (size == 4) {
+            vtd_set_long(s, addr, val);
+        } else {
+            vtd_set_quad(s, addr, val);
+        }
+        break;
+
+    case DMAR_IRTA_REG_HI:
+        VTD_DPRINTF(IR, "DMAR_IRTA_REG_HI write addr 0x%"PRIx64
+                    ", size %d, val 0x%"PRIx64, addr, size, val);
+        assert(size == 4);
+        vtd_set_long(s, addr, val);
+        break;
+
     default:
         VTD_DPRINTF(GENERAL, "error: unhandled reg write addr 0x%"PRIx64
                     ", size %d, val 0x%"PRIx64, addr, size, val);
@@ -1907,6 +2008,295 @@ static Property vtd_properties[] = {
     DEFINE_PROP_END_OF_LIST(),
 };
 
+/* Read IRTE entry with specific index */
+static int vtd_irte_get(IntelIOMMUState *iommu, uint16_t index,
+                        VTD_IR_TableEntry *entry, uint16_t sid)
+{
+    static const uint16_t vtd_svt_mask[VTD_SQ_MAX] = \
+        {0xffff, 0xfffb, 0xfff9, 0xfff8};
+    dma_addr_t addr = 0x00;
+    uint16_t mask, source_id;
+    uint8_t bus, bus_max, bus_min;
+
+    addr = iommu->intr_root + index * sizeof(*entry);
+    if (dma_memory_read(&address_space_memory, addr, entry,
+                        sizeof(*entry))) {
+        VTD_DPRINTF(GENERAL, "error: fail to access IR root at 0x%"PRIx64
+                    " + %"PRIu16, iommu->intr_root, index);
+        return -VTD_FR_IR_ROOT_INVAL;
+    }
+
+    if (!entry->irte.present) {
+        VTD_DPRINTF(GENERAL, "error: present flag not set in IRTE"
+                    " entry index %u value 0x%"PRIx64 " 0x%"PRIx64,
+                    index, le64_to_cpu(entry->data[1]),
+                    le64_to_cpu(entry->data[0]));
+        return -VTD_FR_IR_ENTRY_P;
+    }
+
+    if (entry->irte.__reserved_0 || entry->irte.__reserved_1 ||
+        entry->irte.__reserved_2) {
+        VTD_DPRINTF(GENERAL, "error: IRTE entry index %"PRIu16
+                    " reserved fields non-zero: 0x%"PRIx64 " 0x%"PRIx64,
+                    index, le64_to_cpu(entry->data[1]),
+                    le64_to_cpu(entry->data[0]));
+        return -VTD_FR_IR_IRTE_RSVD;
+    }
+
+    if (sid != X86_IOMMU_SID_INVALID) {
+        /* Validate IRTE SID */
+        source_id = le32_to_cpu(entry->irte.source_id);
+        switch (entry->irte.sid_vtype) {
+        case VTD_SVT_NONE:
+            VTD_DPRINTF(IR, "No SID validation for IRTE index %d", index);
+            break;
+
+        case VTD_SVT_ALL:
+            mask = vtd_svt_mask[entry->irte.sid_q];
+            if ((source_id & mask) != (sid & mask)) {
+                VTD_DPRINTF(GENERAL, "SID validation for IRTE index "
+                            "%d failed (reqid 0x%04x sid 0x%04x)", index,
+                            sid, source_id);
+                return -VTD_FR_IR_SID_ERR;
+            }
+            break;
+
+        case VTD_SVT_BUS:
+            bus_max = source_id >> 8;
+            bus_min = source_id & 0xff;
+            bus = sid >> 8;
+            if (bus > bus_max || bus < bus_min) {
+                VTD_DPRINTF(GENERAL, "SID validation for IRTE index %d "
+                            "failed (bus %d outside %d-%d)", index, bus,
+                            bus_min, bus_max);
+                return -VTD_FR_IR_SID_ERR;
+            }
+            break;
+
+        default:
+            VTD_DPRINTF(GENERAL, "Invalid SVT bits (0x%x) in IRTE index "
+                        "%d", entry->irte.sid_vtype, index);
+            /* Take this as verification failure. */
+            return -VTD_FR_IR_SID_ERR;
+            break;
+        }
+    }
+
+    return 0;
+}
+
+/* Fetch IRQ information of specific IR index */
+static int vtd_remap_irq_get(IntelIOMMUState *iommu, uint16_t index,
+                             VTDIrq *irq, uint16_t sid)
+{
+    VTD_IR_TableEntry irte = {};
+    int ret = 0;
+
+    ret = vtd_irte_get(iommu, index, &irte, sid);
+    if (ret) {
+        return ret;
+    }
+
+    irq->trigger_mode = irte.irte.trigger_mode;
+    irq->vector = irte.irte.vector;
+    irq->delivery_mode = irte.irte.delivery_mode;
+    irq->dest = le32_to_cpu(irte.irte.dest_id);
+    if (!iommu->intr_eime) {
+#define  VTD_IR_APIC_DEST_MASK         (0xff00ULL)
+#define  VTD_IR_APIC_DEST_SHIFT        (8)
+        irq->dest = (irq->dest & VTD_IR_APIC_DEST_MASK) >>
+            VTD_IR_APIC_DEST_SHIFT;
+    }
+    irq->dest_mode = irte.irte.dest_mode;
+    irq->redir_hint = irte.irte.redir_hint;
+
+    VTD_DPRINTF(IR, "remapping interrupt index %d: trig:%u,vec:%u,"
+                "deliver:%u,dest:%u,dest_mode:%u", index,
+                irq->trigger_mode, irq->vector, irq->delivery_mode,
+                irq->dest, irq->dest_mode);
+
+    return 0;
+}
+
+/* Generate one MSI message from VTDIrq info */
+static void vtd_generate_msi_message(VTDIrq *irq, MSIMessage *msg_out)
+{
+    VTD_MSIMessage msg = {};
+
+    /* Generate address bits */
+    msg.dest_mode = irq->dest_mode;
+    msg.redir_hint = irq->redir_hint;
+    msg.dest = irq->dest;
+    msg.__addr_head = cpu_to_le32(0xfee);
+    /* Keep this from original MSI address bits */
+    msg.__not_used = irq->msi_addr_last_bits;
+
+    /* Generate data bits */
+    msg.vector = irq->vector;
+    msg.delivery_mode = irq->delivery_mode;
+    msg.level = 1;
+    msg.trigger_mode = irq->trigger_mode;
+
+    msg_out->address = msg.msi_addr;
+    msg_out->data = msg.msi_data;
+}
+
+/* Interrupt remapping for MSI/MSI-X entry */
+static int vtd_interrupt_remap_msi(IntelIOMMUState *iommu,
+                                   MSIMessage *origin,
+                                   MSIMessage *translated,
+                                   uint16_t sid)
+{
+    int ret = 0;
+    VTD_IR_MSIAddress addr;
+    uint16_t index;
+    VTDIrq irq = {};
+
+    assert(origin && translated);
+
+    if (!iommu || !iommu->intr_enabled) {
+        goto do_not_translate;
+    }
+
+    if (origin->address & VTD_MSI_ADDR_HI_MASK) {
+        VTD_DPRINTF(GENERAL, "error: MSI addr high 32 bits nonzero"
+                    " during interrupt remapping: 0x%"PRIx32,
+                    (uint32_t)((origin->address & VTD_MSI_ADDR_HI_MASK) >> \
+                    VTD_MSI_ADDR_HI_SHIFT));
+        return -VTD_FR_IR_REQ_RSVD;
+    }
+
+    addr.data = origin->address & VTD_MSI_ADDR_LO_MASK;
+    if (le16_to_cpu(addr.addr.__head) != 0xfee) {
+        VTD_DPRINTF(GENERAL, "error: MSI addr low 32 bits invalid: "
+                    "0x%"PRIx32, addr.data);
+        return -VTD_FR_IR_REQ_RSVD;
+    }
+
+    /* This is compatible mode. */
+    if (addr.addr.int_mode != VTD_IR_INT_FORMAT_REMAP) {
+        goto do_not_translate;
+    }
+
+    index = addr.addr.index_h << 15 | le16_to_cpu(addr.addr.index_l);
+
+#define  VTD_IR_MSI_DATA_SUBHANDLE       (0x0000ffff)
+#define  VTD_IR_MSI_DATA_RESERVED        (0xffff0000)
+
+    if (addr.addr.sub_valid) {
+        /* See VT-d spec 5.1.2.2 and 5.1.3 on subhandle */
+        index += origin->data & VTD_IR_MSI_DATA_SUBHANDLE;
+    }
+
+    ret = vtd_remap_irq_get(iommu, index, &irq, sid);
+    if (ret) {
+        return ret;
+    }
+
+    if (addr.addr.sub_valid) {
+        VTD_DPRINTF(IR, "received MSI interrupt");
+        if (origin->data & VTD_IR_MSI_DATA_RESERVED) {
+            VTD_DPRINTF(GENERAL, "error: MSI data bits non-zero for "
+                        "interrupt remappable entry: 0x%"PRIx32,
+                        origin->data);
+            return -VTD_FR_IR_REQ_RSVD;
+        }
+    } else {
+        uint8_t vector = origin->data & 0xff;
+        VTD_DPRINTF(IR, "received IOAPIC interrupt");
+        /* IOAPIC entry vector should be aligned with IRTE vector
+         * (see vt-d spec 5.1.5.1). */
+        if (vector != irq.vector) {
+            VTD_DPRINTF(GENERAL, "IOAPIC vector inconsistent: "
+                        "entry: %d, IRTE: %d, index: %d",
+                        vector, irq.vector, index);
+        }
+    }
+
+    /*
+     * We'd better keep the last two bits, assuming that guest OS
+     * might modify it. Keep it does not hurt after all.
+     */
+    irq.msi_addr_last_bits = addr.addr.__not_care;
+
+    /* Translate VTDIrq to MSI message */
+    vtd_generate_msi_message(&irq, translated);
+
+    VTD_DPRINTF(IR, "mapping MSI 0x%"PRIx64":0x%"PRIx32 " -> "
+                "0x%"PRIx64":0x%"PRIx32, origin->address, origin->data,
+                translated->address, translated->data);
+    return 0;
+
+do_not_translate:
+    memcpy(translated, origin, sizeof(*origin));
+    return 0;
+}
+
+static int vtd_int_remap(X86IOMMUState *iommu, MSIMessage *src,
+                         MSIMessage *dst, uint16_t sid)
+{
+    return vtd_interrupt_remap_msi(INTEL_IOMMU_DEVICE(iommu),
+                                   src, dst, sid);
+}
+
+static MemTxResult vtd_mem_ir_read(void *opaque, hwaddr addr,
+                                   uint64_t *data, unsigned size,
+                                   MemTxAttrs attrs)
+{
+    return MEMTX_OK;
+}
+
+static MemTxResult vtd_mem_ir_write(void *opaque, hwaddr addr,
+                                    uint64_t value, unsigned size,
+                                    MemTxAttrs attrs)
+{
+    int ret = 0;
+    MSIMessage from = {}, to = {};
+    uint16_t sid = X86_IOMMU_SID_INVALID;
+
+    from.address = (uint64_t) addr + VTD_INTERRUPT_ADDR_FIRST;
+    from.data = (uint32_t) value;
+
+    if (!attrs.unspecified) {
+        /* We have explicit Source ID */
+        sid = attrs.requester_id;
+    }
+
+    ret = vtd_interrupt_remap_msi(opaque, &from, &to, sid);
+    if (ret) {
+        /* TODO: report error */
+        VTD_DPRINTF(GENERAL, "int remap fail for addr 0x%"PRIx64
+                    " data 0x%"PRIx32, from.address, from.data);
+        /* Drop this interrupt */
+        return MEMTX_ERROR;
+    }
+
+    VTD_DPRINTF(IR, "delivering MSI 0x%"PRIx64":0x%"PRIx32
+                " for device sid 0x%04x",
+                to.address, to.data, sid);
+
+    if (dma_memory_write(&address_space_memory, to.address,
+                         &to.data, size)) {
+        VTD_DPRINTF(GENERAL, "error: fail to write 0x%"PRIx64
+                    " value 0x%"PRIx32, to.address, to.data);
+    }
+
+    return MEMTX_OK;
+}
+
+static const MemoryRegionOps vtd_mem_ir_ops = {
+    .read_with_attrs = vtd_mem_ir_read,
+    .write_with_attrs = vtd_mem_ir_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .impl = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+};
 
 VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
 {
@@ -1916,7 +2306,8 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
 
     if (!vtd_bus) {
         /* No corresponding free() */
-        vtd_bus = g_malloc0(sizeof(VTDBus) + sizeof(VTDAddressSpace *) * VTD_PCI_DEVFN_MAX);
+        vtd_bus = g_malloc0(sizeof(VTDBus) + sizeof(VTDAddressSpace *) * \
+                            X86_IOMMU_PCI_DEVFN_MAX);
         vtd_bus->bus = bus;
         key = (uintptr_t)bus;
         g_hash_table_insert(s->vtd_as_by_busptr, &key, vtd_bus);
@@ -1933,6 +2324,11 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
         vtd_dev_as->context_cache_entry.context_cache_gen = 0;
         memory_region_init_iommu(&vtd_dev_as->iommu, OBJECT(s),
                                  &s->iommu_ops, "intel_iommu", UINT64_MAX);
+        memory_region_init_io(&vtd_dev_as->iommu_ir, OBJECT(s),
+                              &vtd_mem_ir_ops, s, "intel_iommu_ir",
+                              VTD_INTERRUPT_ADDR_SIZE);
+        memory_region_add_subregion(&vtd_dev_as->iommu, VTD_INTERRUPT_ADDR_FIRST,
+                                    &vtd_dev_as->iommu_ir);
         address_space_init(&vtd_dev_as->as,
                            &vtd_dev_as->iommu, "intel_iommu");
     }
@@ -1944,6 +2340,8 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
  */
 static void vtd_init(IntelIOMMUState *s)
 {
+    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(s);
+
     memset(s->csr, 0, DMAR_REG_SIZE);
     memset(s->wmask, 0, DMAR_REG_SIZE);
     memset(s->w1cmask, 0, DMAR_REG_SIZE);
@@ -1965,6 +2363,10 @@ static void vtd_init(IntelIOMMUState *s)
              VTD_CAP_SAGAW | VTD_CAP_MAMV | VTD_CAP_PSI | VTD_CAP_SLLPS;
     s->ecap = VTD_ECAP_QI | VTD_ECAP_IRO;
 
+    if (x86_iommu->intr_supported) {
+        s->ecap |= VTD_ECAP_IR | VTD_ECAP_EIM | VTD_ECAP_MHMV;
+    }
+
     vtd_reset_context_cache(s);
     vtd_reset_iotlb(s);
 
@@ -2014,6 +2416,11 @@ static void vtd_init(IntelIOMMUState *s)
     /* Fault Recording Registers, 128-bit */
     vtd_define_quad(s, DMAR_FRCD_REG_0_0, 0, 0, 0);
     vtd_define_quad(s, DMAR_FRCD_REG_0_2, 0, 0, 0x8000000000000000ULL);
+
+    /*
+     * Interrupt remapping registers.
+     */
+    vtd_define_quad(s, DMAR_IRTA_REG, 0, 0xfffffffffffff80fULL, 0);
 }
 
 /* Should not reset address_spaces when reset because devices will still use
@@ -2032,7 +2439,7 @@ static AddressSpace *vtd_host_dma_iommu(PCIBus *bus, void *opaque, int devfn)
     IntelIOMMUState *s = opaque;
     VTDAddressSpace *vtd_as;
 
-    assert(0 <= devfn && devfn <= VTD_PCI_DEVFN_MAX);
+    assert(0 <= devfn && devfn <= X86_IOMMU_PCI_DEVFN_MAX);
 
     vtd_as = vtd_find_add_as(s, bus, devfn);
     return &vtd_as->as;
@@ -2040,8 +2447,10 @@ static AddressSpace *vtd_host_dma_iommu(PCIBus *bus, void *opaque, int devfn)
 
 static void vtd_realize(DeviceState *dev, Error **errp)
 {
-    PCIBus *bus = PC_MACHINE(qdev_get_machine())->bus;
+    PCMachineState *pcms = PC_MACHINE(qdev_get_machine());
+    PCIBus *bus = pcms->bus;
     IntelIOMMUState *s = INTEL_IOMMU_DEVICE(dev);
+    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);
 
     VTD_DPRINTF(GENERAL, "");
     memset(s->vtd_as_by_bus_num, 0, sizeof(s->vtd_as_by_bus_num));
@@ -2056,22 +2465,34 @@ static void vtd_realize(DeviceState *dev, Error **errp)
     vtd_init(s);
     sysbus_mmio_map(SYS_BUS_DEVICE(s), 0, Q35_HOST_BRIDGE_IOMMU_ADDR);
     pci_setup_iommu(bus, vtd_host_dma_iommu, dev);
+    /* Pseudo address space under root PCI bus. */
+    pcms->ioapic_as = vtd_host_dma_iommu(bus, s, Q35_PSEUDO_DEVFN_IOAPIC);
+
+    /* Currently Intel IOMMU IR only support "kernel-irqchip={off|split}" */
+    if (x86_iommu->intr_supported && kvm_irqchip_in_kernel() &&
+        !kvm_irqchip_is_split()) {
+        error_report("Intel Interrupt Remapping cannot work with "
+                     "kernel-irqchip=on, please use 'split|off'.");
+        exit(1);
+    }
 }
 
 static void vtd_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    X86IOMMUClass *x86_class = X86_IOMMU_CLASS(klass);
 
     dc->reset = vtd_reset;
-    dc->realize = vtd_realize;
     dc->vmsd = &vtd_vmstate;
     dc->props = vtd_properties;
     dc->hotpluggable = false;
+    x86_class->realize = vtd_realize;
+    x86_class->int_remap = vtd_int_remap;
 }
 
 static const TypeInfo vtd_info = {
     .name          = TYPE_INTEL_IOMMU_DEVICE,
-    .parent        = TYPE_SYS_BUS_DEVICE,
+    .parent        = TYPE_X86_IOMMU_DEVICE,
     .instance_size = sizeof(IntelIOMMUState),
     .class_init    = vtd_class_init,
 };
diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index e5f514c..0829a50 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -110,6 +110,8 @@
 /* Interrupt Address Range */
 #define VTD_INTERRUPT_ADDR_FIRST    0xfee00000ULL
 #define VTD_INTERRUPT_ADDR_LAST     0xfeefffffULL
+#define VTD_INTERRUPT_ADDR_SIZE     (VTD_INTERRUPT_ADDR_LAST - \
+                                     VTD_INTERRUPT_ADDR_FIRST + 1)
 
 /* The shift of source_id in the key of IOTLB hash table */
 #define VTD_IOTLB_SID_SHIFT         36
@@ -172,10 +174,19 @@
 #define VTD_RTADDR_RTT              (1ULL << 11)
 #define VTD_RTADDR_ADDR_MASK        (VTD_HAW_MASK ^ 0xfffULL)
 
+/* IRTA_REG */
+#define VTD_IRTA_ADDR_MASK          (VTD_HAW_MASK ^ 0xfffULL)
+#define VTD_IRTA_EIME               (1ULL << 11)
+#define VTD_IRTA_SIZE_MASK          (0xfULL)
+
 /* ECAP_REG */
 /* (offset >> 4) << 8 */
 #define VTD_ECAP_IRO                (DMAR_IOTLB_REG_OFFSET << 4)
 #define VTD_ECAP_QI                 (1ULL << 1)
+/* Interrupt Remapping support */
+#define VTD_ECAP_IR                 (1ULL << 3)
+#define VTD_ECAP_EIM                (1ULL << 4)
+#define VTD_ECAP_MHMV               (15ULL << 20)
 
 /* CAP_REG */
 /* (offset >> 4) << 24 */
@@ -265,6 +276,19 @@ typedef enum VTDFaultReason {
      * context-entry.
      */
     VTD_FR_CONTEXT_ENTRY_TT,
+
+    /* Interrupt remapping transition faults */
+    VTD_FR_IR_REQ_RSVD = 0x20, /* One or more IR request reserved
+                                * fields set */
+    VTD_FR_IR_INDEX_OVER = 0x21, /* Index value greater than max */
+    VTD_FR_IR_ENTRY_P = 0x22,    /* Present (P) not set in IRTE */
+    VTD_FR_IR_ROOT_INVAL = 0x23, /* IR Root table invalid */
+    VTD_FR_IR_IRTE_RSVD = 0x24,  /* IRTE Rsvd field non-zero with
+                                  * Present flag set */
+    VTD_FR_IR_REQ_COMPAT = 0x25, /* Encountered compatible IR
+                                  * request while disabled */
+    VTD_FR_IR_SID_ERR = 0x26,   /* Invalid Source-ID */
+
     /* This is not a normal fault reason. We use this to indicate some faults
      * that are not referenced by the VT-d specification.
      * Fault event with such reason should not be recorded.
@@ -275,17 +299,35 @@ typedef enum VTDFaultReason {
 
 #define VTD_CONTEXT_CACHE_GEN_MAX       0xffffffffUL
 
+/* Interrupt Entry Cache Invalidation Descriptor: VT-d 6.5.2.7. */
+struct VTDInvDescIEC {
+    uint32_t type:4;            /* Should always be 0x4 */
+    uint32_t granularity:1;     /* If set, it's global IR invalidation */
+    uint32_t resved_1:22;
+    uint32_t index_mask:5;      /* 2^N for continuous int invalidation */
+    uint32_t index:16;          /* Start index to invalidate */
+    uint32_t reserved_2:16;
+};
+typedef struct VTDInvDescIEC VTDInvDescIEC;
+
 /* Queued Invalidation Descriptor */
-struct VTDInvDesc {
-    uint64_t lo;
-    uint64_t hi;
+union VTDInvDesc {
+    struct {
+        uint64_t lo;
+        uint64_t hi;
+    };
+    union {
+        VTDInvDescIEC iec;
+    };
 };
-typedef struct VTDInvDesc VTDInvDesc;
+typedef union VTDInvDesc VTDInvDesc;
 
 /* Masks for struct VTDInvDesc */
 #define VTD_INV_DESC_TYPE               0xf
 #define VTD_INV_DESC_CC                 0x1 /* Context-cache Invalidate Desc */
 #define VTD_INV_DESC_IOTLB              0x2
+#define VTD_INV_DESC_IEC                0x4 /* Interrupt Entry Cache
+                                               Invalidate Descriptor */
 #define VTD_INV_DESC_WAIT               0x5 /* Invalidation Wait Descriptor */
 #define VTD_INV_DESC_NONE               0   /* Not an Invalidate Descriptor */
 
diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c
index 1a429e5..8238fbc 100644
--- a/hw/i386/kvm/pci-assign.c
+++ b/hw/i386/kvm/pci-assign.c
@@ -974,10 +974,9 @@ static void assigned_dev_update_msi(PCIDevice *pci_dev)
     }
 
     if (ctrl_byte & PCI_MSI_FLAGS_ENABLE) {
-        MSIMessage msg = msi_get_message(pci_dev, 0);
         int virq;
 
-        virq = kvm_irqchip_add_msi_route(kvm_state, msg, pci_dev);
+        virq = kvm_irqchip_add_msi_route(kvm_state, 0, pci_dev);
         if (virq < 0) {
             perror("assigned_dev_update_msi: kvm_irqchip_add_msi_route");
             return;
@@ -1016,6 +1015,7 @@ static void assigned_dev_update_msi_msg(PCIDevice *pci_dev)
 
     kvm_irqchip_update_msi_route(kvm_state, assigned_dev->msi_virq[0],
                                  msi_get_message(pci_dev, 0), pci_dev);
+    kvm_irqchip_commit_routes(kvm_state);
 }
 
 static bool assigned_dev_msix_masked(MSIXTableEntry *entry)
@@ -1042,7 +1042,6 @@ static int assigned_dev_update_msix_mmio(PCIDevice *pci_dev)
     uint16_t entries_nr = 0;
     int i, r = 0;
     MSIXTableEntry *entry = adev->msix_table;
-    MSIMessage msg;
 
     /* Get the usable entry number for allocating */
     for (i = 0; i < adev->msix_max; i++, entry++) {
@@ -1079,9 +1078,7 @@ static int assigned_dev_update_msix_mmio(PCIDevice *pci_dev)
             continue;
         }
 
-        msg.address = entry->addr_lo | ((uint64_t)entry->addr_hi << 32);
-        msg.data = entry->data;
-        r = kvm_irqchip_add_msi_route(kvm_state, msg, pci_dev);
+        r = kvm_irqchip_add_msi_route(kvm_state, i, pci_dev);
         if (r < 0) {
             return r;
         }
@@ -1606,6 +1603,7 @@ static void assigned_dev_msix_mmio_write(void *opaque, hwaddr addr,
                 if (ret) {
                     error_report("Error updating irq routing entry (%d)", ret);
                 }
+                kvm_irqchip_commit_routes(kvm_state);
             }
         }
     }
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index ac7a4d5..9e3c70f 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1473,6 +1473,9 @@ void pc_memory_init(PCMachineState *pcms,
         rom_add_option(option_rom[i].name, option_rom[i].bootindex);
     }
     pcms->fw_cfg = fw_cfg;
+
+    /* Init default IOAPIC address space */
+    pcms->ioapic_as = &address_space_memory;
 }
 
 qemu_irq pc_allocate_cpu_irq(void)
diff --git a/hw/i386/trace-events b/hw/i386/trace-events
index ea77bc2..b4882c1 100644
--- a/hw/i386/trace-events
+++ b/hw/i386/trace-events
@@ -10,3 +10,6 @@ xen_pv_mmio_write(uint64_t addr) "WARNING: write to Xen PV Device MMIO space (ad
 # hw/i386/pc.c
 mhp_pc_dimm_assigned_slot(int slot) "0x%d"
 mhp_pc_dimm_assigned_address(uint64_t addr) "0x%"PRIx64
+
+# hw/i386/x86-iommu.c
+x86_iommu_iec_notify(bool global, uint32_t index, uint32_t mask) "Notify IEC invalidation: global=%d index=%" PRIu32 " mask=%" PRIu32
diff --git a/hw/i386/x86-iommu.c b/hw/i386/x86-iommu.c
new file mode 100644
index 0000000..ce26b2a
--- /dev/null
+++ b/hw/i386/x86-iommu.c
@@ -0,0 +1,128 @@
+/*
+ * QEMU emulation of common X86 IOMMU
+ *
+ * Copyright (C) 2016 Peter Xu, Red Hat <peterx@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/sysbus.h"
+#include "hw/boards.h"
+#include "hw/i386/x86-iommu.h"
+#include "qemu/error-report.h"
+#include "trace.h"
+
+void x86_iommu_iec_register_notifier(X86IOMMUState *iommu,
+                                     iec_notify_fn fn, void *data)
+{
+    IEC_Notifier *notifier = g_new0(IEC_Notifier, 1);
+
+    notifier->iec_notify = fn;
+    notifier->private = data;
+
+    QLIST_INSERT_HEAD(&iommu->iec_notifiers, notifier, list);
+}
+
+void x86_iommu_iec_notify_all(X86IOMMUState *iommu, bool global,
+                              uint32_t index, uint32_t mask)
+{
+    IEC_Notifier *notifier;
+
+    trace_x86_iommu_iec_notify(global, index, mask);
+
+    QLIST_FOREACH(notifier, &iommu->iec_notifiers, list) {
+        if (notifier->iec_notify) {
+            notifier->iec_notify(notifier->private, global,
+                                 index, mask);
+        }
+    }
+}
+
+/* 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;
+}
+
+static void x86_iommu_realize(DeviceState *dev, Error **errp)
+{
+    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);
+    X86IOMMUClass *x86_class = X86_IOMMU_GET_CLASS(dev);
+    QLIST_INIT(&x86_iommu->iec_notifiers);
+    if (x86_class->realize) {
+        x86_class->realize(dev, errp);
+    }
+    x86_iommu_set_default(X86_IOMMU_DEVICE(dev));
+}
+
+static void x86_iommu_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    dc->realize = x86_iommu_realize;
+}
+
+static bool x86_iommu_intremap_prop_get(Object *o, Error **errp)
+{
+    X86IOMMUState *s = X86_IOMMU_DEVICE(o);
+    return s->intr_supported;
+}
+
+static void x86_iommu_intremap_prop_set(Object *o, bool value, Error **errp)
+{
+    X86IOMMUState *s = X86_IOMMU_DEVICE(o);
+    s->intr_supported = value;
+}
+
+static void x86_iommu_instance_init(Object *o)
+{
+    X86IOMMUState *s = X86_IOMMU_DEVICE(o);
+
+    /* By default, do not support IR */
+    s->intr_supported = false;
+    object_property_add_bool(o, "intremap", x86_iommu_intremap_prop_get,
+                             x86_iommu_intremap_prop_set, NULL);
+}
+
+static const TypeInfo x86_iommu_info = {
+    .name          = TYPE_X86_IOMMU_DEVICE,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_init = x86_iommu_instance_init,
+    .instance_size = sizeof(X86IOMMUState),
+    .class_init    = x86_iommu_class_init,
+    .class_size    = sizeof(X86IOMMUClass),
+    .abstract      = true,
+};
+
+static void x86_iommu_register_types(void)
+{
+    type_register_static(&x86_iommu_info);
+}
+
+type_init(x86_iommu_register_types)