Hi Eric,
>-----Original Message-----
>From: Eric Auger <eric.au...@redhat.com>
>Subject: [RFC v2 2/7] virtio-iommu: Implement set|unset]_iommu_device()
>callbacks
>
>Implement PCIIOMMUOPs [set|unset]_iommu_device() callbacks.
>In set(), a VirtioHostIOMMUDevice is allocated which holds
>a reference to the HostIOMMUDevice. This object is stored in a hash
>table indexed by PCI BDF. The handle to the Host IOMMU device
>will allow to retrieve information related to the physical IOMMU.
>
>Signed-off-by: Eric Auger <eric.au...@redhat.com>
>---
> include/hw/virtio/virtio-iommu.h | 9 ++++
> hw/virtio/virtio-iommu.c | 87
>++++++++++++++++++++++++++++++++
> 2 files changed, 96 insertions(+)
>
>diff --git a/include/hw/virtio/virtio-iommu.h b/include/hw/virtio/virtio-
>iommu.h
>index 83a52cc446..4f664ea0c4 100644
>--- a/include/hw/virtio/virtio-iommu.h
>+++ b/include/hw/virtio/virtio-iommu.h
>@@ -45,6 +45,14 @@ typedef struct IOMMUDevice {
> bool probe_done;
> } IOMMUDevice;
>
>+typedef struct VirtioHostIOMMUDevice {
>+ void *viommu;
>+ PCIBus *bus;
>+ uint8_t devfn;
>+ HostIOMMUDevice *dev;
>+ QLIST_ENTRY(VirtioHostIOMMUDevice) next;
>+} VirtioHostIOMMUDevice;
>+
> typedef struct IOMMUPciBus {
> PCIBus *bus;
> IOMMUDevice *pbdev[]; /* Parent array is sparse, so dynamically alloc
>*/
>@@ -57,6 +65,7 @@ struct VirtIOIOMMU {
> struct virtio_iommu_config config;
> uint64_t features;
> GHashTable *as_by_busptr;
>+ GHashTable *host_iommu_devices;
> IOMMUPciBus *iommu_pcibus_by_bus_num[PCI_BUS_MAX];
> PCIBus *primary_bus;
> ReservedRegion *prop_resv_regions;
>diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
>index 1326c6ec41..0680a357f0 100644
>--- a/hw/virtio/virtio-iommu.c
>+++ b/hw/virtio/virtio-iommu.c
>@@ -28,6 +28,7 @@
> #include "sysemu/kvm.h"
> #include "sysemu/reset.h"
> #include "sysemu/sysemu.h"
>+#include "sysemu/host_iommu_device.h"
Not sure if better to move this to include/hw/virtio/virtio-iommu.h
as HostIOMMUDevice is used there.
> #include "qemu/reserved-region.h"
> #include "qemu/units.h"
> #include "qapi/error.h"
>@@ -69,6 +70,11 @@ typedef struct VirtIOIOMMUMapping {
> uint32_t flags;
> } VirtIOIOMMUMapping;
>
>+struct hiod_key {
>+ PCIBus *bus;
>+ uint8_t devfn;
>+};
>+
> static inline uint16_t virtio_iommu_get_bdf(IOMMUDevice *dev)
> {
> return PCI_BUILD_BDF(pci_bus_num(dev->bus), dev->devfn);
>@@ -462,8 +468,86 @@ static AddressSpace
>*virtio_iommu_find_add_as(PCIBus *bus, void *opaque,
> return &sdev->as;
> }
>
>+static gboolean hiod_equal(gconstpointer v1, gconstpointer v2)
>+{
>+ const struct hiod_key *key1 = v1;
>+ const struct hiod_key *key2 = v2;
>+
>+ return (key1->bus == key2->bus) && (key1->devfn == key2->devfn);
>+}
>+
>+static guint hiod_hash(gconstpointer v)
>+{
>+ const struct hiod_key *key = v;
>+ guint value = (guint)(uintptr_t)key->bus;
>+
>+ return (guint)(value << 8 | key->devfn);
>+}
>+
>+static VirtioHostIOMMUDevice *
>+get_host_iommu_device(VirtIOIOMMU *viommu, PCIBus *bus, int devfn) {
>+ struct hiod_key key = {
>+ .bus = bus,
>+ .devfn = devfn,
>+ };
>+
>+ return g_hash_table_lookup(viommu->host_iommu_devices, &key);
>+}
>+
>+static bool virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque,
>int devfn,
>+ HostIOMMUDevice *hiod, Error **errp)
>+{
>+ VirtIOIOMMU *viommu = opaque;
>+ VirtioHostIOMMUDevice *vhiod;
>+ struct hiod_key *new_key;
>+
>+ assert(hiod);
>+
>+ vhiod = get_host_iommu_device(viommu, bus, devfn);
>+ if (vhiod) {
>+ error_setg(errp, "VirtioHostIOMMUDevice already exists");
>+ return false;
>+ }
>+
>+ vhiod = g_malloc0(sizeof(VirtioHostIOMMUDevice));
>+ vhiod->bus = bus;
>+ vhiod->devfn = (uint8_t)devfn;
>+ vhiod->viommu = viommu;
>+ vhiod->dev = hiod;
>+
>+ new_key = g_malloc(sizeof(*new_key));
>+ new_key->bus = bus;
>+ new_key->devfn = devfn;
>+
>+ object_ref(hiod);
>+ g_hash_table_insert(viommu->host_iommu_devices, new_key, vhiod);
>+
>+ return true;
>+}
>+
>+static void
>+virtio_iommu_unset_iommu_device(PCIBus *bus, void *opaque, int devfn)
>+{
>+ VirtIOIOMMU *viommu = opaque;
>+ VirtioHostIOMMUDevice *vhiod;
>+ struct hiod_key key = {
>+ .bus = bus,
>+ .devfn = devfn,
>+ };
>+
>+ vhiod = g_hash_table_lookup(viommu->host_iommu_devices, &key);
>+ if (!vhiod) {
>+ return;
>+ }
>+
>+ g_hash_table_remove(viommu->host_iommu_devices, &key);
>+ object_unref(vhiod->dev);
This looks a use-after-free.
Thanks
Zhenzhong
>+}
>+
> static const PCIIOMMUOps virtio_iommu_ops = {
> .get_address_space = virtio_iommu_find_add_as,
>+ .set_iommu_device = virtio_iommu_set_iommu_device,
>+ .unset_iommu_device = virtio_iommu_unset_iommu_device,
> };
>
> static int virtio_iommu_attach(VirtIOIOMMU *s,
>@@ -1357,6 +1441,9 @@ static void
>virtio_iommu_device_realize(DeviceState *dev, Error **errp)
>
> s->as_by_busptr = g_hash_table_new_full(NULL, NULL, NULL, g_free);
>
>+ s->host_iommu_devices = g_hash_table_new_full(hiod_hash,
>hiod_equal,
>+ g_free, g_free);
>+
> if (s->primary_bus) {
> pci_setup_iommu(s->primary_bus, &virtio_iommu_ops, s);
> } else {
>--
>2.41.0
