+/**
+ * pci_epf_add_vepf() - associate virtual EP function to physical EP function
+ * @epf_pf: the physical EP function to which the virtual EP function should be
+ * associated
+ * @epf_vf: the virtual EP function to be added
+ *
+ * A physical endpoint function can be associated with multiple virtual
+ * endpoint functions. Invoke pci_epf_add_epf() to add a virtual PCI endpoint
+ * function to a physical PCI endpoint function.
+ */
+int pci_epf_add_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf)
+{
+ u32 vfunc_no;
+
+ if (IS_ERR_OR_NULL(epf_pf) || IS_ERR_OR_NULL(epf_vf))
+ return -EINVAL;
+
+ if (epf_pf->epc || epf_vf->epc || epf_vf->epf_pf)
+ return -EBUSY;
+
+ if (epf_pf->sec_epc || epf_vf->sec_epc)
+ return -EBUSY;
+
+ mutex_lock(&epf_pf->lock);
+ vfunc_no = find_first_zero_bit(&epf_pf->vfunction_num_map,
+ BITS_PER_LONG);
+ if (vfunc_no >= BITS_PER_LONG) {
+ mutex_unlock(&epf_pf->lock);
+ return -EINVAL;
+ }
+
+ set_bit(vfunc_no, &epf_pf->vfunction_num_map);
+ epf_vf->vfunc_no = vfunc_no;
+
+ epf_vf->epf_pf = epf_pf;
+ epf_vf->is_vf = true;
+
+ list_add_tail(&epf_vf->list, &epf_pf->pci_vepf);
+ mutex_unlock(&epf_pf->lock);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pci_epf_add_vepf);
+
+/**
+ * pci_epf_remove_vepf() - remove virtual EP function from physical EP function
+ * @epf_pf: the physical EP function from which the virtual EP function should
+ * be removed
+ * @epf_vf: the virtual EP function to be removed
+ *
+ * Invoke to remove a virtual endpoint function from the physcial endpoint
+ * function.
+ */
+void pci_epf_remove_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf)
+{
+ if (IS_ERR_OR_NULL(epf_pf) || IS_ERR_OR_NULL(epf_vf))
+ return;
+
+ mutex_lock(&epf_pf->lock);
+ clear_bit(epf_vf->vfunc_no, &epf_pf->vfunction_num_map);
+ list_del(&epf_vf->list);
+ mutex_unlock(&epf_pf->lock);
+}
+EXPORT_SYMBOL_GPL(pci_epf_remove_vepf);
+