Re: [PATCH V3 1/3] vDPA/ifcvf: deduce VIRTIO device ID when probe

[Jason Wang]

在 2021/4/16 下午3:16, Zhu Lingshan 写道:

This commit deduces VIRTIO device ID as device type when probe,
then ifcvf_vdpa_get_device_id() can simply return the ID.
ifcvf_vdpa_get_features() and ifcvf_vdpa_get_config_size()
can work properly based on the device ID.

Signed-off-by: Zhu Lingshan <lingshan....@intel.com>
---
  drivers/vdpa/ifcvf/ifcvf_base.h |  1 +
  drivers/vdpa/ifcvf/ifcvf_main.c | 30 ++++++++++++++++++------------
  2 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h b/drivers/vdpa/ifcvf/ifcvf_base.h
index b2eeb16b9c2c..1c04cd256fa7 100644
--- a/drivers/vdpa/ifcvf/ifcvf_base.h
+++ b/drivers/vdpa/ifcvf/ifcvf_base.h
@@ -84,6 +84,7 @@ struct ifcvf_hw {
        u32 notify_off_multiplier;
        u64 req_features;
        u64 hw_features;
+       u32 dev_type;
        struct virtio_pci_common_cfg __iomem *common_cfg;
        void __iomem *net_cfg;
        struct vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index 44d7586019da..469a9b5737b7 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -323,19 +323,9 @@ static u32 ifcvf_vdpa_get_generation(struct vdpa_device 
*vdpa_dev)

static u32 ifcvf_vdpa_get_device_id(struct vdpa_device *vdpa_dev)

  {
-       struct ifcvf_adapter *adapter = vdpa_to_adapter(vdpa_dev);
-       struct pci_dev *pdev = adapter->pdev;
-       u32 ret = -ENODEV;
-
-       if (pdev->device < 0x1000 || pdev->device > 0x107f)
-               return ret;
-
-       if (pdev->device < 0x1040)
-               ret =  pdev->subsystem_device;
-       else
-               ret =  pdev->device - 0x1040;
+       struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);

- return ret;

+       return vf->dev_type;
  }

static u32 ifcvf_vdpa_get_vendor_id(struct vdpa_device *vdpa_dev)

@@ -466,6 +456,22 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct 
pci_device_id *id)
        pci_set_drvdata(pdev, adapter);

vf = &adapter->vf;

+
+       /* This drirver drives both modern virtio devices and transitional
+        * devices in modern mode.
+        * vDPA requires feature bit VIRTIO_F_ACCESS_PLATFORM,
+        * so legacy devices and transitional devices in legacy
+        * mode will not work for vDPA, this driver will not
+        * drive devices with legacy interface.
+        */
+       if (pdev->device < 0x1000 || pdev->device > 0x107f)
+               return -EOPNOTSUPP;

So this seems useless, id_table has already did that for us:

The driver supports:

#define IFCVF_DEVICE_ID         0x1041

and

#define C5000X_PL_BLK_DEVICE_ID        0x1001

I think we can never reach the condition above.

Thanks

+
+       if (pdev->device < 0x1040)
+               vf->dev_type =  pdev->subsystem_device;
+       else
+               vf->dev_type =  pdev->device - 0x1040;
+
        vf->base = pcim_iomap_table(pdev);

adapter->pdev = pdev;