@@ -89,6 +89,8 @@ static enum pci_protocol_version_t pci_protocol_version;
#define STATUS_REVISION_MISMATCH 0xC0000059
+#define SLOT_NAME_SIZE 21
+
/*
* Message Types
*/
@@ -494,6 +496,7 @@ struct hv_pci_dev {
struct list_head list_entry;
refcount_t refs;
enum hv_pcichild_state state;
+ struct pci_slot *pci_slot;
struct pci_function_description desc;
bool reported_missing;
struct hv_pcibus_device *hbus;
@@ -1457,6 +1460,28 @@ static void prepopulate_bars(struct hv_pcibus_device *hbus)
spin_unlock_irqrestore(&hbus->device_list_lock, flags);
}
+static void hv_pci_assign_slots(struct hv_pcibus_device *hbus)
+{
+ struct hv_pci_dev *hpdev;
+ char name[SLOT_NAME_SIZE];
+ unsigned long flags;
+ int slot_nr;
+
+ spin_lock_irqsave(&hbus->device_list_lock, flags);
+ list_for_each_entry(hpdev, &hbus->children, list_entry) {
+ if (hpdev->pci_slot)
+ continue;
+
+ slot_nr = PCI_SLOT(wslot_to_devfn(hpdev->desc.win_slot.slot));
+ snprintf(name, SLOT_NAME_SIZE, "%u", hpdev->desc.ser);
+ hpdev->pci_slot = pci_create_slot(hbus->pci_bus, slot_nr,
+ name, NULL);
+ if (!hpdev->pci_slot)
+ pr_warn("pci_create slot %s failed\n", name);
+ }
+ spin_unlock_irqrestore(&hbus->device_list_lock, flags);
+}
+
/**
* create_root_hv_pci_bus() - Expose a new root PCI bus
* @hbus: Root PCI bus, as understood by this driver
@@ -1480,6 +1505,7 @@ static int create_root_hv_pci_bus(struct hv_pcibus_device *hbus)
pci_lock_rescan_remove();
pci_scan_child_bus(hbus->pci_bus);
pci_bus_assign_resources(hbus->pci_bus);
+ hv_pci_assign_slots(hbus);
pci_bus_add_devices(hbus->pci_bus);
pci_unlock_rescan_remove();
hbus->state = hv_pcibus_installed;
@@ -1742,6 +1768,7 @@ static void pci_devices_present_work(struct work_struct *work)
*/
pci_lock_rescan_remove();
pci_scan_child_bus(hbus->pci_bus);
+ hv_pci_assign_slots(hbus);
pci_unlock_rescan_remove();
break;
@@ -1858,6 +1885,9 @@ static void hv_eject_device_work(struct work_struct *work)
list_del(&hpdev->list_entry);
spin_unlock_irqrestore(&hpdev->hbus->device_list_lock, flags);
+ if (hpdev->pci_slot)
+ pci_destroy_slot(hpdev->pci_slot);
+
memset(&ctxt, 0, sizeof(ctxt));
ejct_pkt = (struct pci_eject_response *)&ctxt.pkt.message;
ejct_pkt->message_type.type = PCI_EJECTION_COMPLETE;
The Hyper-V host API for PCI provides a unique "serial number" which can be used as basis for sysfs PCI slot table. This can be useful for cases where userspace wants to find the PCI device based on serial number. When an SR-IOV NIC is added, the host sends an attach message with serial number. The kernel doesn't use the serial number, but it is useful when doing the same thing in a userspace driver such as the DPDK. By having /sys/bus/pci/slots/N it provides a direct way to find the matching PCI device. There may be some cases where serial number is not unique such as when using GPU's. But the PCI slot infrastructure will handle that by adding suffix "2-1" etc. This has a side effect which may also be useful. The common udev network device naming policy uses the slot information (rather than PCI address). This causes udev to give shorter network device names for VF devices. It does not break applications or startup because the VF device must never be configured directly. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> --- drivers/pci/controller/pci-hyperv.c | 30 +++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+)