diff mbox series

[v6,14/19] hw/pci: Introduce helper function pci_device_get_iommu_bus_devfn()

Message ID 20240603061023.269738-15-zhenzhong.duan@intel.com (mailing list archive)
State New, archived
Headers show
Series Add a host IOMMU device abstraction to check with vIOMMU | expand

Commit Message

Duan, Zhenzhong June 3, 2024, 6:10 a.m. UTC 
Extract out pci_device_get_iommu_bus_devfn() from
pci_device_iommu_address_space() to facilitate
implementation of pci_device_[set|unset]_iommu_device()
in following patch.

No functional change intended.

Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 hw/pci/pci.c | 48 +++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 45 insertions(+), 3 deletions(-)

Comments

Eric Auger June 3, 2024, 1:40 p.m. UTC | #1 
On 6/3/24 08:10, Zhenzhong Duan wrote:
> Extract out pci_device_get_iommu_bus_devfn() from
> pci_device_iommu_address_space() to facilitate
> implementation of pci_device_[set|unset]_iommu_device()
> in following patch.
>
> No functional change intended.
>
> Signed-off-by: Yi Liu <yi.l.liu@intel.com>
> Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Eric
> ---
>  hw/pci/pci.c | 48 +++++++++++++++++++++++++++++++++++++++++++++---
>  1 file changed, 45 insertions(+), 3 deletions(-)
>
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 324c1302d2..02a4bb2af6 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -2648,11 +2648,27 @@ static void pci_device_class_base_init(ObjectClass *klass, void *data)
>      }
>  }
>  
> -AddressSpace *pci_device_iommu_address_space(PCIDevice *dev)
> +/*
> + * Get IOMMU root bus, aliased bus and devfn of a PCI device
> + *
> + * IOMMU root bus is needed by all call sites to call into iommu_ops.
> + * For call sites which don't need aliased BDF, passing NULL to
> + * aliased_[bus|devfn] is allowed.
> + *
> + * @piommu_bus: return root #PCIBus backed by an IOMMU for the PCI device.
> + *
> + * @aliased_bus: return aliased #PCIBus of the PCI device, optional.
> + *
> + * @aliased_devfn: return aliased devfn of the PCI device, optional.
> + */
> +static void pci_device_get_iommu_bus_devfn(PCIDevice *dev,
> +                                           PCIBus **piommu_bus,
> +                                           PCIBus **aliased_bus,
> +                                           int *aliased_devfn)
>  {
>      PCIBus *bus = pci_get_bus(dev);
>      PCIBus *iommu_bus = bus;
> -    uint8_t devfn = dev->devfn;
> +    int devfn = dev->devfn;
>  
>      while (iommu_bus && !iommu_bus->iommu_ops && iommu_bus->parent_dev) {
>          PCIBus *parent_bus = pci_get_bus(iommu_bus->parent_dev);
> @@ -2693,7 +2709,33 @@ AddressSpace *pci_device_iommu_address_space(PCIDevice *dev)
>  
>          iommu_bus = parent_bus;
>      }
> -    if (!pci_bus_bypass_iommu(bus) && iommu_bus->iommu_ops) {
> +
> +    assert(0 <= devfn && devfn < PCI_DEVFN_MAX);
> +    assert(iommu_bus);
> +
> +    if (pci_bus_bypass_iommu(bus) || !iommu_bus->iommu_ops) {
> +        iommu_bus = NULL;
> +    }
> +
> +    *piommu_bus = iommu_bus;
> +
> +    if (aliased_bus) {
> +        *aliased_bus = bus;
> +    }
> +
> +    if (aliased_devfn) {
> +        *aliased_devfn = devfn;
> +    }
> +}
> +
> +AddressSpace *pci_device_iommu_address_space(PCIDevice *dev)
> +{
> +    PCIBus *bus;
> +    PCIBus *iommu_bus;
> +    int devfn;
> +
> +    pci_device_get_iommu_bus_devfn(dev, &iommu_bus, &bus, &devfn);
> +    if (iommu_bus) {
>          return iommu_bus->iommu_ops->get_address_space(bus,
>                                   iommu_bus->iommu_opaque, devfn);
>      }
diff mbox series

Patch

diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 324c1302d2..02a4bb2af6 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -2648,11 +2648,27 @@  static void pci_device_class_base_init(ObjectClass *klass, void *data)
     }
 }
 
-AddressSpace *pci_device_iommu_address_space(PCIDevice *dev)
+/*
+ * Get IOMMU root bus, aliased bus and devfn of a PCI device
+ *
+ * IOMMU root bus is needed by all call sites to call into iommu_ops.
+ * For call sites which don't need aliased BDF, passing NULL to
+ * aliased_[bus|devfn] is allowed.
+ *
+ * @piommu_bus: return root #PCIBus backed by an IOMMU for the PCI device.
+ *
+ * @aliased_bus: return aliased #PCIBus of the PCI device, optional.
+ *
+ * @aliased_devfn: return aliased devfn of the PCI device, optional.
+ */
+static void pci_device_get_iommu_bus_devfn(PCIDevice *dev,
+                                           PCIBus **piommu_bus,
+                                           PCIBus **aliased_bus,
+                                           int *aliased_devfn)
 {
     PCIBus *bus = pci_get_bus(dev);
     PCIBus *iommu_bus = bus;
-    uint8_t devfn = dev->devfn;
+    int devfn = dev->devfn;
 
     while (iommu_bus && !iommu_bus->iommu_ops && iommu_bus->parent_dev) {
         PCIBus *parent_bus = pci_get_bus(iommu_bus->parent_dev);
@@ -2693,7 +2709,33 @@  AddressSpace *pci_device_iommu_address_space(PCIDevice *dev)
 
         iommu_bus = parent_bus;
     }
-    if (!pci_bus_bypass_iommu(bus) && iommu_bus->iommu_ops) {
+
+    assert(0 <= devfn && devfn < PCI_DEVFN_MAX);
+    assert(iommu_bus);
+
+    if (pci_bus_bypass_iommu(bus) || !iommu_bus->iommu_ops) {
+        iommu_bus = NULL;
+    }
+
+    *piommu_bus = iommu_bus;
+
+    if (aliased_bus) {
+        *aliased_bus = bus;
+    }
+
+    if (aliased_devfn) {
+        *aliased_devfn = devfn;
+    }
+}
+
+AddressSpace *pci_device_iommu_address_space(PCIDevice *dev)
+{
+    PCIBus *bus;
+    PCIBus *iommu_bus;
+    int devfn;
+
+    pci_device_get_iommu_bus_devfn(dev, &iommu_bus, &bus, &devfn);
+    if (iommu_bus) {
         return iommu_bus->iommu_ops->get_address_space(bus,
                                  iommu_bus->iommu_opaque, devfn);
     }