Add a "supports_vf" flag to struct pci_driver to let drivers declare
Virtual Function (VF) support. If a driver does not support VFs, then
the PCI driver core will not probe() any VFs for that driver's devices.

On the Rust side, add a const "SUPPORTS_VF" Driver trait, defaulting to
false: drivers must explicitly opt into VF support.

Cc: Alexandre Courbot <[email protected]>
Cc: Alistair Popple <[email protected]>
Cc: Joel Fernandes <[email protected]>
Cc: Zhi Wang <[email protected]>
Cc: Alex Williamson <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Suggested-by: Danilo Krummrich <[email protected]>
Signed-off-by: John Hubbard <[email protected]>
---
 drivers/pci/pci-driver.c | 3 +++
 include/linux/pci.h      | 1 +
 rust/kernel/pci.rs       | 4 ++++
 3 files changed, 8 insertions(+)

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 63665240ae87..588666cc7254 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -412,6 +412,9 @@ static int __pci_device_probe(struct pci_driver *drv, 
struct pci_dev *pci_dev)
        if (drv->probe) {
                error = -ENODEV;
 
+               if (pci_dev->is_virtfn && !drv->supports_vf)
+                       return error;
+
                id = pci_match_device(drv, pci_dev);
                if (id)
                        error = pci_call_probe(drv, pci_dev, id);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 59876de13860..92510886a086 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -983,6 +983,7 @@ struct pci_driver {
        struct device_driver    driver;
        struct pci_dynids       dynids;
        bool driver_managed_dma;
+       bool supports_vf;       /* Will bind to Virtual Functions */
 };
 
 #define to_pci_driver(__drv)   \
diff --git a/rust/kernel/pci.rs b/rust/kernel/pci.rs
index 7fcc5f6022c1..c5d036770e65 100644
--- a/rust/kernel/pci.rs
+++ b/rust/kernel/pci.rs
@@ -47,6 +47,7 @@ unsafe fn register(
             (*pdrv.get()).probe = Some(Self::probe_callback);
             (*pdrv.get()).remove = Some(Self::remove_callback);
             (*pdrv.get()).id_table = T::ID_TABLE.as_ptr();
+            (*pdrv.get()).supports_vf = T::SUPPORTS_VF;
         }
 
         // SAFETY: `pdrv` is guaranteed to be a valid `RegType`.
@@ -268,6 +269,9 @@ pub trait Driver: Send {
     /// The table of device ids supported by the driver.
     const ID_TABLE: IdTable<Self::IdInfo>;
 
+    /// Whether the driver supports Virtual Functions.
+    const SUPPORTS_VF: bool = false;
+
     /// PCI driver probe.
     ///
     /// Called when a new pci device is added or discovered. Implementers 
should
-- 
2.51.0

Reply via email to