[RFC Patch 03/12] IXGBE: Add sysfs interface for Qemu to migrate VF status in the PF driver

From: Lan Tianyu
Date: Wed Oct 21 2015 - 12:55:08 EST


This patch is to add sysfs interface state_in_pf under sysfs directory
of VF PCI device for Qemu to get and put VF status in the PF driver during
migration.

Signed-off-by: Lan Tianyu <tianyu.lan@xxxxxxxxx>
---
drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c | 156 ++++++++++++++++++++++++-
1 file changed, 155 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
index ab2a2e2..89671eb 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
@@ -124,6 +124,157 @@ static int __ixgbe_enable_sriov(struct ixgbe_adapter *adapter)
return -ENOMEM;
}

+#define IXGBE_PCI_VFCOMMAND 0x4
+#define IXGBE_PCI_VFMSIXMC 0x72
+#define IXGBE_SRIOV_VF_OFFSET 0x180
+#define IXGBE_SRIOV_VF_STRIDE 0x2
+
+#define to_adapter(dev) ((struct ixgbe_adapter *)(pci_get_drvdata(to_pci_dev(dev)->physfn)))
+
+struct state_in_pf {
+ u16 command;
+ u16 msix_message_control;
+ struct vf_data_storage vf_data;
+};
+
+static struct pci_dev *ixgbe_get_virtfn_dev(struct pci_dev *pdev, int vfn)
+{
+ u16 rid = pdev->devfn + IXGBE_SRIOV_VF_OFFSET + IXGBE_SRIOV_VF_STRIDE * vfn;
+ return pci_get_bus_and_slot(pdev->bus->number + (rid >> 8), rid & 0xff);
+}
+
+static ssize_t ixgbe_show_state_in_pf(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ixgbe_adapter *adapter = to_adapter(dev);
+ struct pci_dev *pdev = adapter->pdev, *vdev;
+ struct pci_dev *vf_pdev = to_pci_dev(dev);
+ struct ixgbe_hw *hw = &adapter->hw;
+ struct state_in_pf *state = (struct state_in_pf *)buf;
+ int vfn = vf_pdev->virtfn_index;
+ u32 reg, reg_offset, vf_shift;
+
+ /* Clear VF mac and disable VF */
+ ixgbe_del_mac_filter(adapter, adapter->vfinfo[vfn].vf_mac_addresses, vfn);
+
+ /* Record PCI configurations */
+ vdev = ixgbe_get_virtfn_dev(pdev, vfn);
+ if (vdev) {
+ pci_read_config_word(vdev, IXGBE_PCI_VFCOMMAND, &state->command);
+ pci_read_config_word(vdev, IXGBE_PCI_VFMSIXMC, &state->msix_message_control);
+ }
+ else
+ printk(KERN_WARNING "Unable to find VF device.\n");
+
+ /* Record states hold by PF */
+ memcpy(&state->vf_data, &adapter->vfinfo[vfn], sizeof(struct vf_data_storage));
+
+ vf_shift = vfn % 32;
+ reg_offset = vfn / 32;
+
+ reg = IXGBE_READ_REG(hw, IXGBE_VFTE(reg_offset));
+ reg &= ~(1 << vf_shift);
+ IXGBE_WRITE_REG(hw, IXGBE_VFTE(reg_offset), reg);
+
+ reg = IXGBE_READ_REG(hw, IXGBE_VFRE(reg_offset));
+ reg &= ~(1 << vf_shift);
+ IXGBE_WRITE_REG(hw, IXGBE_VFRE(reg_offset), reg);
+
+ reg = IXGBE_READ_REG(hw, IXGBE_VMECM(reg_offset));
+ reg &= ~(1 << vf_shift);
+ IXGBE_WRITE_REG(hw, IXGBE_VMECM(reg_offset), reg);
+
+ return sizeof(struct state_in_pf);
+}
+
+static ssize_t ixgbe_store_state_in_pf(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ixgbe_adapter *adapter = to_adapter(dev);
+ struct pci_dev *pdev = adapter->pdev, *vdev;
+ struct pci_dev *vf_pdev = to_pci_dev(dev);
+ struct state_in_pf *state = (struct state_in_pf *)buf;
+ int vfn = vf_pdev->virtfn_index;
+
+ /* Check struct size */
+ if (count != sizeof(struct state_in_pf)) {
+ printk(KERN_ERR "State in PF size does not fit.\n");
+ goto out;
+ }
+
+ /* Restore PCI configurations */
+ vdev = ixgbe_get_virtfn_dev(pdev, vfn);
+ if (vdev) {
+ pci_write_config_word(vdev, IXGBE_PCI_VFCOMMAND, state->command);
+ pci_write_config_word(vdev, IXGBE_PCI_VFMSIXMC, state->msix_message_control);
+ }
+
+ /* Restore states hold by PF */
+ memcpy(&adapter->vfinfo[vfn], &state->vf_data, sizeof(struct vf_data_storage));
+
+ out:
+ return count;
+}
+
+static struct device_attribute ixgbe_per_state_in_pf_attribute =
+ __ATTR(state_in_pf, S_IRUGO | S_IWUSR,
+ ixgbe_show_state_in_pf, ixgbe_store_state_in_pf);
+
+void ixgbe_add_vf_attrib(struct ixgbe_adapter *adapter)
+{
+ struct pci_dev *pdev = adapter->pdev;
+ struct pci_dev *vfdev;
+ unsigned short vf_id;
+ int pos, ret;
+
+ pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_SRIOV);
+ if (!pos)
+ return;
+
+ /* get the device ID for the VF */
+ pci_read_config_word(pdev, pos + PCI_SRIOV_VF_DID, &vf_id);
+
+ vfdev = pci_get_device(pdev->vendor, vf_id, NULL);
+
+ while (vfdev) {
+ if (vfdev->is_virtfn) {
+ ret = device_create_file(&vfdev->dev,
+ &ixgbe_per_state_in_pf_attribute);
+ if (ret)
+ pr_warn("Unable to add VF attribute for dev %s,\n",
+ dev_name(&vfdev->dev));
+ }
+
+ vfdev = pci_get_device(pdev->vendor, vf_id, vfdev);
+ }
+}
+
+void ixgbe_remove_vf_attrib(struct ixgbe_adapter *adapter)
+{
+ struct pci_dev *pdev = adapter->pdev;
+ struct pci_dev *vfdev;
+ unsigned short vf_id;
+ int pos;
+
+ pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_SRIOV);
+ if (!pos)
+ return;
+
+ /* get the device ID for the VF */
+ pci_read_config_word(pdev, pos + PCI_SRIOV_VF_DID, &vf_id);
+
+ vfdev = pci_get_device(pdev->vendor, vf_id, NULL);
+
+ while (vfdev) {
+ if (vfdev->is_virtfn) {
+ device_remove_file(&vfdev->dev, &ixgbe_per_state_in_pf_attribute);
+ }
+
+ vfdev = pci_get_device(pdev->vendor, vf_id, vfdev);
+ }
+}
+
/* Note this function is called when the user wants to enable SR-IOV
* VFs using the now deprecated module parameter
*/
@@ -198,6 +349,9 @@ int ixgbe_disable_sriov(struct ixgbe_adapter *adapter)
if (!(adapter->flags & IXGBE_FLAG_SRIOV_ENABLED))
return 0;

+
+ ixgbe_remove_vf_attrib(adapter);
+
#ifdef CONFIG_PCI_IOV
/*
* If our VFs are assigned we cannot shut down SR-IOV
@@ -284,7 +438,7 @@ static int ixgbe_pci_sriov_enable(struct pci_dev *dev, int num_vfs)
return err;
}
ixgbe_sriov_reinit(adapter);
-
+ ixgbe_add_vf_attrib(adapter);
return num_vfs;
#else
return 0;
--
1.8.4.rc0.1.g8f6a3e5.dirty

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