diff mbox series

[for-4.2,v10,05/15] virtio-iommu: Add the iommu regions

Message ID 20190730172137.23114-6-eric.auger@redhat.com
State New
Headers show
Series VIRTIO-IOMMU device | expand

Commit Message

Eric Auger July 30, 2019, 5:21 p.m. UTC 
This patch initializes the iommu memory regions so that
PCIe end point transactions get translated. The translation
function is not yet implemented though.

Signed-off-by: Eric Auger <eric.auger@redhat.com>

---

v9 -> v10:
- remove pc/virt machine headers
- virtio_iommu_find_add_as: mr_index introduced in that patch
  and name properly freed

v6 -> v7:
- use primary_bus
- rebase on new translate proto featuring iommu_idx

v5 -> v6:
- include qapi/error.h
- fix g_hash_table_lookup key in virtio_iommu_find_add_as

v4 -> v5:
- use PCI bus handle as a key
- use get_primary_pci_bus() callback

v3 -> v4:
- add trace_virtio_iommu_init_iommu_mr

v2 -> v3:
- use IOMMUMemoryRegion
- iommu mr name built with BDF
- rename smmu_get_sid into virtio_iommu_get_sid and use PCI_BUILD_BDF
---
 hw/virtio/trace-events           |  2 +
 hw/virtio/virtio-iommu.c         | 92 ++++++++++++++++++++++++++++++++
 include/hw/virtio/virtio-iommu.h |  2 +
 3 files changed, 96 insertions(+)

Comments

Peter Xu Aug. 16, 2019, 4 a.m. UTC | #1 
On Tue, Jul 30, 2019 at 07:21:27PM +0200, Eric Auger wrote:

[...]

>  static void virtio_iommu_get_config(VirtIODevice *vdev, uint8_t *config_data)
>  {
>      VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
> @@ -266,6 +333,15 @@ static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
>      virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MAP_UNMAP);
>      virtio_add_feature(&s->features, VIRTIO_IOMMU_F_BYPASS);
>      virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MMIO);
> +
> +    memset(s->as_by_bus_num, 0, sizeof(s->as_by_bus_num));
> +    s->as_by_busptr = g_hash_table_new(NULL, NULL);

VT-d was using g_hash_table_new_full() so that potentially VTDBus can
still be freed.  Here for IOMMUPCIBus allocated in
virtio_iommu_find_add_as() I think it'll be leaked if we remove
entries in the hash table?

So I started to wonder whether PCI/PCIe buses are allowed to be
plugged/unplugged after all because I never tried.  With latest
5.3.0-rc4 guest I gave it a shot and I see the error below.  It could
be something that I did wrong or it could be simply that it's not
working at all.  Have you tried anything like that?  Michael/Alex?

bin=x86_64-softmmu/qemu-system-x86_64
$bin -M q35,accel=kvm,kernel-irqchip=on -smp 8 -m 2G -cpu host \
     -monitor telnet::6666,server,nowait -nographic \
     -device e1000,netdev=net0 \
     -netdev user,id=net0,hostfwd=tcp::5555-:22 \
     -device pcie-pci-bridge,bus=pcie.0,id=pci.1 \
     -drive file=/images/default.qcow2,if=none,cache=none,id=drive0 \
     -device virtio-blk,drive=drive0

(qemu) device_add pci-bridge,bus=pci.1,id=pci.2,chassis_nr=1,addr=1.0

[   66.172352] pci 0000:01:01.0: [1b36:0001] type 01 class 0x060400
[   66.176897] pci 0000:01:01.0: reg 0x10: [mem 0x00000000-0x000000ff 64bit]
[   66.186130] pci 0000:01:01.0: No bus number available for hot-added bridge
[   66.189489] shpchp 0000:00:03.0: BAR 14: assigned [mem 0x80000000-0x800fffff]
[   66.193235] pci 0000:01:01.0: BAR 0: assigned [mem 0x80000000-0x800000ff 64bit]
[   66.198587] shpchp 0000:00:03.0: PCI bridge to [bus 01]
[   66.204113] shpchp 0000:00:03.0:   bridge window [mem 0x80000000-0x800fffff]
[   66.215212] shpchp 0000:01:01.0: HPC vendor_id 1b36 device_id 1 ss_vid 0 ss_did 0
[   66.218531] shpchp 0000:01:01.0: enabling device (0000 -> 0002)
[   66.229204] BUG: kernel NULL pointer dereference, address: 00000000000000e2
[   66.232124] #PF: supervisor write access in kernel mode
[   66.234369] #PF: error_code(0x0002) - not-present page
[   66.236585] PGD 0 P4D 0
[   66.237431] Oops: 0002 [#1] SMP PTI
[   66.238617] CPU: 2 PID: 277 Comm: kworker/2:1 Kdump: loaded Not tainted 5.3.0-rc4 #85
[   66.241200] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[   66.244916] Workqueue: shpchp-1 shpchp_pushbutton_thread
[   66.246583] RIP: 0010:shpc_init.cold+0x5c3/0x8a1
[   66.248041] Code: 24 90 01 00 00 8b 49 08 40 80 fe 02 0f 85 f4 01 00 00 f7 c1 00 00 00 f0 0f 84 b2 01 00 00 b9 13 00 00 00 80 3d 33 40 38 02 00 <88> 8a e26
[   66.253771] RSP: 0018:ffffc9000025bb68 EFLAGS: 00010246
[   66.255418] RAX: 00000000000000ff RBX: 0000000000000000 RCX: 0000000000000000
[   66.257763] RDX: 0000000000000000 RSI: ffffffff826bcd01 RDI: ffffffff826bcd60
[   66.260065] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
[   66.263184] R10: 0000000000000005 R11: 0000000000000000 R12: ffff888032425400
[   66.265706] R13: ffffc9000017109c R14: ffff888033da7000 R15: 000000000000001f
[   66.268200] FS:  0000000000000000(0000) GS:ffff88807fc80000(0000) knlGS:0000000000000000
[   66.270826] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   66.272731] CR2: 00000000000000e2 CR3: 0000000033afc002 CR4: 0000000000360ee0
[   66.275373] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   66.277947] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   66.279965] Call Trace:
[   66.280627]  shpc_probe+0x91/0x32b
[   66.281644]  local_pci_probe+0x42/0x80
[   66.282752]  pci_device_probe+0x107/0x1a0
[   66.283877]  really_probe+0xf0/0x380
[   66.284862]  driver_probe_device+0x59/0xd0
[   66.285988]  ? driver_allows_async_probing+0x50/0x50
[   66.287937]  bus_for_each_drv+0x7e/0xc0
[   66.289752]  __device_attach+0xe1/0x160
[   66.292076]  pci_bus_add_device+0x4b/0x70
[   66.295244]  pci_bus_add_devices+0x2c/0x64
[   66.297429]  shpchp_configure_device+0xc1/0xe0
[   66.299692]  board_added+0x117/0x240
[   66.301589]  shpchp_enable_slot+0x121/0x2e0
[   66.303686]  shpchp_pushbutton_thread+0x70/0xa0
[   66.305941]  process_one_work+0x221/0x500
[   66.308253]  worker_thread+0x50/0x3b0
[   66.310512]  kthread+0xfb/0x130
[   66.312422]  ? process_one_work+0x500/0x500
[   66.314617]  ? kthread_park+0x80/0x80
[   66.316489]  ret_from_fork+0x3a/0x50
[   66.318293] Modules linked in: intel_rapl_msr intel_rapl_common kvm_intel kvm crct10dif_pclmul bochs_drm crc32_pclmul drm_vram_helper ghash_clmulni_intel o
[   66.331179] CR2: 00000000000000e2
[   66.333090] ---[ end trace cfc73b2e92e207d4 ]---
[   66.335431] RIP: 0010:shpc_init.cold+0x5c3/0x8a1
[   66.337790] Code: 24 90 01 00 00 8b 49 08 40 80 fe 02 0f 85 f4 01 00 00 f7 c1 00 00 00 f0 0f 84 b2 01 00 00 b9 13 00 00 00 80 3d 33 40 38 02 00 <88> 8a e26
[   66.346561] RSP: 0018:ffffc9000025bb68 EFLAGS: 00010246
[   66.348659] RAX: 00000000000000ff RBX: 0000000000000000 RCX: 0000000000000000
[   66.351412] RDX: 0000000000000000 RSI: ffffffff826bcd01 RDI: ffffffff826bcd60
[   66.354204] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
[   66.357013] R10: 0000000000000005 R11: 0000000000000000 R12: ffff888032425400
[   66.360117] R13: ffffc9000017109c R14: ffff888033da7000 R15: 000000000000001f
[   66.362953] FS:  0000000000000000(0000) GS:ffff88807fc80000(0000) knlGS:0000000000000000
[   66.366003] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   66.368756] CR2: 00000000000000e2 CR3: 0000000033afc002 CR4: 0000000000360ee0
[   66.371769] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   66.376036] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Regards,
Eric Auger Aug. 29, 2019, 12:51 p.m. UTC | #2 
Hi Peter,

On 8/16/19 6:00 AM, Peter Xu wrote:
> On Tue, Jul 30, 2019 at 07:21:27PM +0200, Eric Auger wrote:
> 
> [...]
> 
>>  static void virtio_iommu_get_config(VirtIODevice *vdev, uint8_t *config_data)
>>  {
>>      VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
>> @@ -266,6 +333,15 @@ static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
>>      virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MAP_UNMAP);
>>      virtio_add_feature(&s->features, VIRTIO_IOMMU_F_BYPASS);
>>      virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MMIO);
>> +
>> +    memset(s->as_by_bus_num, 0, sizeof(s->as_by_bus_num));
>> +    s->as_by_busptr = g_hash_table_new(NULL, NULL);
> 
> VT-d was using g_hash_table_new_full() so that potentially VTDBus can
> still be freed.  Here for IOMMUPCIBus allocated in
> virtio_iommu_find_add_as() I think it'll be leaked if we remove
> entries in the hash table?
> 
> So I started to wonder whether PCI/PCIe buses are allowed to be
> plugged/unplugged after all because I never tried.  With latest
> 5.3.0-rc4 guest I gave it a shot and I see the error below.  It could
> be something that I did wrong or it could be simply that it's not
> working at all.  Have you tried anything like that?  Michael/Alex?

I have never tried this on my end.

However looking at docs/pcie_pci_bridge.txt it seems possible to hotplug
a pcie_pci_bridge downstream to a pcie-root-port under specific
conditions (see limitations section). So I guess the situation you
describe may happen. I switched to _full version.

Thanks

Eric


> 
> bin=x86_64-softmmu/qemu-system-x86_64
> $bin -M q35,accel=kvm,kernel-irqchip=on -smp 8 -m 2G -cpu host \
>      -monitor telnet::6666,server,nowait -nographic \
>      -device e1000,netdev=net0 \
>      -netdev user,id=net0,hostfwd=tcp::5555-:22 \
>      -device pcie-pci-bridge,bus=pcie.0,id=pci.1 \
>      -drive file=/images/default.qcow2,if=none,cache=none,id=drive0 \
>      -device virtio-blk,drive=drive0
> 
> (qemu) device_add pci-bridge,bus=pci.1,id=pci.2,chassis_nr=1,addr=1.0
> 
> [   66.172352] pci 0000:01:01.0: [1b36:0001] type 01 class 0x060400
> [   66.176897] pci 0000:01:01.0: reg 0x10: [mem 0x00000000-0x000000ff 64bit]
> [   66.186130] pci 0000:01:01.0: No bus number available for hot-added bridge
> [   66.189489] shpchp 0000:00:03.0: BAR 14: assigned [mem 0x80000000-0x800fffff]
> [   66.193235] pci 0000:01:01.0: BAR 0: assigned [mem 0x80000000-0x800000ff 64bit]
> [   66.198587] shpchp 0000:00:03.0: PCI bridge to [bus 01]
> [   66.204113] shpchp 0000:00:03.0:   bridge window [mem 0x80000000-0x800fffff]
> [   66.215212] shpchp 0000:01:01.0: HPC vendor_id 1b36 device_id 1 ss_vid 0 ss_did 0
> [   66.218531] shpchp 0000:01:01.0: enabling device (0000 -> 0002)
> [   66.229204] BUG: kernel NULL pointer dereference, address: 00000000000000e2
> [   66.232124] #PF: supervisor write access in kernel mode
> [   66.234369] #PF: error_code(0x0002) - not-present page
> [   66.236585] PGD 0 P4D 0
> [   66.237431] Oops: 0002 [#1] SMP PTI
> [   66.238617] CPU: 2 PID: 277 Comm: kworker/2:1 Kdump: loaded Not tainted 5.3.0-rc4 #85
> [   66.241200] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
> [   66.244916] Workqueue: shpchp-1 shpchp_pushbutton_thread
> [   66.246583] RIP: 0010:shpc_init.cold+0x5c3/0x8a1
> [   66.248041] Code: 24 90 01 00 00 8b 49 08 40 80 fe 02 0f 85 f4 01 00 00 f7 c1 00 00 00 f0 0f 84 b2 01 00 00 b9 13 00 00 00 80 3d 33 40 38 02 00 <88> 8a e26
> [   66.253771] RSP: 0018:ffffc9000025bb68 EFLAGS: 00010246
> [   66.255418] RAX: 00000000000000ff RBX: 0000000000000000 RCX: 0000000000000000
> [   66.257763] RDX: 0000000000000000 RSI: ffffffff826bcd01 RDI: ffffffff826bcd60
> [   66.260065] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
> [   66.263184] R10: 0000000000000005 R11: 0000000000000000 R12: ffff888032425400
> [   66.265706] R13: ffffc9000017109c R14: ffff888033da7000 R15: 000000000000001f
> [   66.268200] FS:  0000000000000000(0000) GS:ffff88807fc80000(0000) knlGS:0000000000000000
> [   66.270826] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [   66.272731] CR2: 00000000000000e2 CR3: 0000000033afc002 CR4: 0000000000360ee0
> [   66.275373] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [   66.277947] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [   66.279965] Call Trace:
> [   66.280627]  shpc_probe+0x91/0x32b
> [   66.281644]  local_pci_probe+0x42/0x80
> [   66.282752]  pci_device_probe+0x107/0x1a0
> [   66.283877]  really_probe+0xf0/0x380
> [   66.284862]  driver_probe_device+0x59/0xd0
> [   66.285988]  ? driver_allows_async_probing+0x50/0x50
> [   66.287937]  bus_for_each_drv+0x7e/0xc0
> [   66.289752]  __device_attach+0xe1/0x160
> [   66.292076]  pci_bus_add_device+0x4b/0x70
> [   66.295244]  pci_bus_add_devices+0x2c/0x64
> [   66.297429]  shpchp_configure_device+0xc1/0xe0
> [   66.299692]  board_added+0x117/0x240
> [   66.301589]  shpchp_enable_slot+0x121/0x2e0
> [   66.303686]  shpchp_pushbutton_thread+0x70/0xa0
> [   66.305941]  process_one_work+0x221/0x500
> [   66.308253]  worker_thread+0x50/0x3b0
> [   66.310512]  kthread+0xfb/0x130
> [   66.312422]  ? process_one_work+0x500/0x500
> [   66.314617]  ? kthread_park+0x80/0x80
> [   66.316489]  ret_from_fork+0x3a/0x50
> [   66.318293] Modules linked in: intel_rapl_msr intel_rapl_common kvm_intel kvm crct10dif_pclmul bochs_drm crc32_pclmul drm_vram_helper ghash_clmulni_intel o
> [   66.331179] CR2: 00000000000000e2
> [   66.333090] ---[ end trace cfc73b2e92e207d4 ]---
> [   66.335431] RIP: 0010:shpc_init.cold+0x5c3/0x8a1
> [   66.337790] Code: 24 90 01 00 00 8b 49 08 40 80 fe 02 0f 85 f4 01 00 00 f7 c1 00 00 00 f0 0f 84 b2 01 00 00 b9 13 00 00 00 80 3d 33 40 38 02 00 <88> 8a e26
> [   66.346561] RSP: 0018:ffffc9000025bb68 EFLAGS: 00010246
> [   66.348659] RAX: 00000000000000ff RBX: 0000000000000000 RCX: 0000000000000000
> [   66.351412] RDX: 0000000000000000 RSI: ffffffff826bcd01 RDI: ffffffff826bcd60
> [   66.354204] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
> [   66.357013] R10: 0000000000000005 R11: 0000000000000000 R12: ffff888032425400
> [   66.360117] R13: ffffc9000017109c R14: ffff888033da7000 R15: 000000000000001f
> [   66.362953] FS:  0000000000000000(0000) GS:ffff88807fc80000(0000) knlGS:0000000000000000
> [   66.366003] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [   66.368756] CR2: 00000000000000e2 CR3: 0000000033afc002 CR4: 0000000000360ee0
> [   66.371769] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [   66.376036] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> 
> Regards,
>
diff mbox series

Patch

diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index c7276116e7..b32169d56c 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -65,3 +65,5 @@  virtio_iommu_attach(uint32_t domain_id, uint32_t ep_id) "domain=%d endpoint=%d"
 virtio_iommu_detach(uint32_t domain_id, uint32_t ep_id) "domain=%d endpoint=%d"
 virtio_iommu_map(uint32_t domain_id, uint64_t virt_start, uint64_t virt_end, uint64_t phys_start, uint32_t flags) "domain=%d virt_start=0x%"PRIx64" virt_end=0x%"PRIx64 " phys_start=0x%"PRIx64" flags=%d"
 virtio_iommu_unmap(uint32_t domain_id, uint64_t virt_start, uint64_t virt_end) "domain=%d virt_start=0x%"PRIx64" virt_end=0x%"PRIx64
+virtio_iommu_translate(const char *name, uint32_t rid, uint64_t iova, int flag) "mr=%s rid=%d addr=0x%"PRIx64" flag=%d"
+virtio_iommu_init_iommu_mr(char *iommu_mr) "init %s"
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 658249c81e..1610e2f773 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -22,6 +22,8 @@ 
 #include "qemu-common.h"
 #include "hw/virtio/virtio.h"
 #include "sysemu/kvm.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
 #include "trace.h"
 
 #include "standard-headers/linux/virtio_ids.h"
@@ -33,6 +35,50 @@ 
 /* Max size */
 #define VIOMMU_DEFAULT_QUEUE_SIZE 256
 
+static inline uint16_t virtio_iommu_get_sid(IOMMUDevice *dev)
+{
+    return PCI_BUILD_BDF(pci_bus_num(dev->bus), dev->devfn);
+}
+
+static AddressSpace *virtio_iommu_find_add_as(PCIBus *bus, void *opaque,
+                                              int devfn)
+{
+    VirtIOIOMMU *s = opaque;
+    IOMMUPciBus *sbus = g_hash_table_lookup(s->as_by_busptr, bus);
+    static uint32_t mr_index;
+    IOMMUDevice *sdev;
+
+    if (!sbus) {
+        sbus = g_malloc0(sizeof(IOMMUPciBus) +
+                         sizeof(IOMMUDevice *) * IOMMU_PCI_DEVFN_MAX);
+        sbus->bus = bus;
+        g_hash_table_insert(s->as_by_busptr, bus, sbus);
+    }
+
+    sdev = sbus->pbdev[devfn];
+    if (!sdev) {
+        char *name = g_strdup_printf("%s-%d-%d",
+                                     TYPE_VIRTIO_IOMMU_MEMORY_REGION,
+                                     mr_index++, devfn);
+        sdev = sbus->pbdev[devfn] = g_malloc0(sizeof(IOMMUDevice));
+
+        sdev->viommu = s;
+        sdev->bus = bus;
+        sdev->devfn = devfn;
+
+        trace_virtio_iommu_init_iommu_mr(name);
+
+        memory_region_init_iommu(&sdev->iommu_mr, sizeof(sdev->iommu_mr),
+                                 TYPE_VIRTIO_IOMMU_MEMORY_REGION,
+                                 OBJECT(s), name,
+                                 UINT64_MAX);
+        address_space_init(&sdev->as,
+                           MEMORY_REGION(&sdev->iommu_mr), TYPE_VIRTIO_IOMMU);
+        g_free(name);
+    }
+    return &sdev->as;
+}
+
 static int virtio_iommu_attach(VirtIOIOMMU *s,
                                struct virtio_iommu_req_attach *req)
 {
@@ -192,6 +238,27 @@  out:
     }
 }
 
+static IOMMUTLBEntry virtio_iommu_translate(IOMMUMemoryRegion *mr, hwaddr addr,
+                                            IOMMUAccessFlags flag,
+                                            int iommu_idx)
+{
+    IOMMUDevice *sdev = container_of(mr, IOMMUDevice, iommu_mr);
+    uint32_t sid;
+
+    IOMMUTLBEntry entry = {
+        .target_as = &address_space_memory,
+        .iova = addr,
+        .translated_addr = addr,
+        .addr_mask = ~(hwaddr)0,
+        .perm = IOMMU_NONE,
+    };
+
+    sid = virtio_iommu_get_sid(sdev);
+
+    trace_virtio_iommu_translate(mr->parent_obj.name, sid, addr, flag);
+    return entry;
+}
+
 static void virtio_iommu_get_config(VirtIODevice *vdev, uint8_t *config_data)
 {
     VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
@@ -266,6 +333,15 @@  static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
     virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MAP_UNMAP);
     virtio_add_feature(&s->features, VIRTIO_IOMMU_F_BYPASS);
     virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MMIO);
+
+    memset(s->as_by_bus_num, 0, sizeof(s->as_by_bus_num));
+    s->as_by_busptr = g_hash_table_new(NULL, NULL);
+
+    if (s->primary_bus) {
+        pci_setup_iommu(s->primary_bus, virtio_iommu_find_add_as, s);
+    } else {
+        error_setg(errp, "VIRTIO-IOMMU is not attached to any PCI bus!");
+    }
 }
 
 static void virtio_iommu_device_unrealize(DeviceState *dev, Error **errp)
@@ -324,6 +400,14 @@  static void virtio_iommu_class_init(ObjectClass *klass, void *data)
     vdc->vmsd = &vmstate_virtio_iommu_device;
 }
 
+static void virtio_iommu_memory_region_class_init(ObjectClass *klass,
+                                                  void *data)
+{
+    IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_CLASS(klass);
+
+    imrc->translate = virtio_iommu_translate;
+}
+
 static const TypeInfo virtio_iommu_info = {
     .name = TYPE_VIRTIO_IOMMU,
     .parent = TYPE_VIRTIO_DEVICE,
@@ -332,9 +416,17 @@  static const TypeInfo virtio_iommu_info = {
     .class_init = virtio_iommu_class_init,
 };
 
+static const TypeInfo virtio_iommu_memory_region_info = {
+    .parent = TYPE_IOMMU_MEMORY_REGION,
+    .name = TYPE_VIRTIO_IOMMU_MEMORY_REGION,
+    .class_init = virtio_iommu_memory_region_class_init,
+};
+
+
 static void virtio_register_types(void)
 {
     type_register_static(&virtio_iommu_info);
+    type_register_static(&virtio_iommu_memory_region_info);
 }
 
 type_init(virtio_register_types)
diff --git a/include/hw/virtio/virtio-iommu.h b/include/hw/virtio/virtio-iommu.h
index 4d47b6abeb..f55f48d304 100644
--- a/include/hw/virtio/virtio-iommu.h
+++ b/include/hw/virtio/virtio-iommu.h
@@ -28,6 +28,8 @@ 
 #define VIRTIO_IOMMU(obj) \
         OBJECT_CHECK(VirtIOIOMMU, (obj), TYPE_VIRTIO_IOMMU)
 
+#define TYPE_VIRTIO_IOMMU_MEMORY_REGION "virtio-iommu-memory-region"
+
 #define IOMMU_PCI_BUS_MAX      256
 #define IOMMU_PCI_DEVFN_MAX    256