// SPDX-License-Identifier: GPL-2.0 /* * Irqdomain for Linux to run as the root partition on Microsoft Hypervisor. * * Authors: * Sunil Muthuswamy * Wei Liu */ #include #include #include static int hv_map_interrupt(union hv_device_id device_id, bool level, int cpu, int vector, struct hv_interrupt_entry *entry) { struct hv_input_map_device_interrupt *input; struct hv_output_map_device_interrupt *output; struct hv_device_interrupt_descriptor *intr_desc; unsigned long flags; u64 status; int nr_bank, var_size; local_irq_save(flags); input = *this_cpu_ptr(hyperv_pcpu_input_arg); output = *this_cpu_ptr(hyperv_pcpu_output_arg); intr_desc = &input->interrupt_descriptor; memset(input, 0, sizeof(*input)); input->partition_id = hv_current_partition_id; input->device_id = device_id.as_uint64; intr_desc->interrupt_type = HV_X64_INTERRUPT_TYPE_FIXED; intr_desc->vector_count = 1; intr_desc->target.vector = vector; if (level) intr_desc->trigger_mode = HV_INTERRUPT_TRIGGER_MODE_LEVEL; else intr_desc->trigger_mode = HV_INTERRUPT_TRIGGER_MODE_EDGE; intr_desc->target.vp_set.valid_bank_mask = 0; intr_desc->target.vp_set.format = HV_GENERIC_SET_SPARSE_4K; nr_bank = cpumask_to_vpset(&(intr_desc->target.vp_set), cpumask_of(cpu)); if (nr_bank < 0) { local_irq_restore(flags); pr_err("%s: unable to generate VP set\n", __func__); return EINVAL; } intr_desc->target.flags = HV_DEVICE_INTERRUPT_TARGET_PROCESSOR_SET; /* * var-sized hypercall, var-size starts after vp_mask (thus * vp_set.format does not count, but vp_set.valid_bank_mask * does). */ var_size = nr_bank + 1; status = hv_do_rep_hypercall(HVCALL_MAP_DEVICE_INTERRUPT, 0, var_size, input, output); *entry = output->interrupt_entry; local_irq_restore(flags); if (!hv_result_success(status)) pr_err("%s: hypercall failed, status %lld\n", __func__, status); return hv_result(status); } static int hv_unmap_interrupt(u64 id, struct hv_interrupt_entry *old_entry) { unsigned long flags; struct hv_input_unmap_device_interrupt *input; struct hv_interrupt_entry *intr_entry; u64 status; local_irq_save(flags); input = *this_cpu_ptr(hyperv_pcpu_input_arg); memset(input, 0, sizeof(*input)); intr_entry = &input->interrupt_entry; input->partition_id = hv_current_partition_id; input->device_id = id; *intr_entry = *old_entry; status = hv_do_hypercall(HVCALL_UNMAP_DEVICE_INTERRUPT, input, NULL); local_irq_restore(flags); return hv_result(status); } #ifdef CONFIG_PCI_MSI struct rid_data { struct pci_dev *bridge; u32 rid; }; static int get_rid_cb(struct pci_dev *pdev, u16 alias, void *data) { struct rid_data *rd = data; u8 bus = PCI_BUS_NUM(rd->rid); if (pdev->bus->number != bus || PCI_BUS_NUM(alias) != bus) { rd->bridge = pdev; rd->rid = alias; } return 0; } static union hv_device_id hv_build_pci_dev_id(struct pci_dev *dev) { union hv_device_id dev_id; struct rid_data data = { .bridge = NULL, .rid = PCI_DEVID(dev->bus->number, dev->devfn) }; pci_for_each_dma_alias(dev, get_rid_cb, &data); dev_id.as_uint64 = 0; dev_id.device_type = HV_DEVICE_TYPE_PCI; dev_id.pci.segment = pci_domain_nr(dev->bus); dev_id.pci.bdf.bus = PCI_BUS_NUM(data.rid); dev_id.pci.bdf.device = PCI_SLOT(data.rid); dev_id.pci.bdf.function = PCI_FUNC(data.rid); dev_id.pci.source_shadow = HV_SOURCE_SHADOW_NONE; if (data.bridge) { int pos; /* * Microsoft Hypervisor requires a bus range when the bridge is * running in PCI-X mode. * * To distinguish conventional vs PCI-X bridge, we can check * the bridge's PCI-X Secondary Status Register, Secondary Bus * Mode and Frequency bits. See PCI Express to PCI/PCI-X Bridge * Specification Revision 1.0 5.2.2.1.3. * * Value zero means it is in conventional mode, otherwise it is * in PCI-X mode. */ pos = pci_find_capability(data.bridge, PCI_CAP_ID_PCIX); if (pos) { u16 status; pci_read_config_word(data.bridge, pos + PCI_X_BRIDGE_SSTATUS, &status); if (status & PCI_X_SSTATUS_FREQ) { /* Non-zero, PCI-X mode */ u8 sec_bus, sub_bus; dev_id.pci.source_shadow = HV_SOURCE_SHADOW_BRIDGE_BUS_RANGE; pci_read_config_byte(data.bridge, PCI_SECONDARY_BUS, &sec_bus); dev_id.pci.shadow_bus_range.secondary_bus = sec_bus; pci_read_config_byte(data.bridge, PCI_SUBORDINATE_BUS, &sub_bus); dev_id.pci.shadow_bus_range.subordinate_bus = sub_bus; } } } return dev_id; } static int hv_map_msi_interrupt(struct pci_dev *dev, int cpu, int vector, struct hv_interrupt_entry *entry) { union hv_device_id device_id = hv_build_pci_dev_id(dev); return hv_map_interrupt(device_id, false, cpu, vector, entry); } static inline void entry_to_msi_msg(struct hv_interrupt_entry *entry, struct msi_msg *msg) { /* High address is always 0 */ msg->address_hi = 0; msg->address_lo = entry->msi_entry.address.as_uint32; msg->data = entry->msi_entry.data.as_uint32; } static int hv_unmap_msi_interrupt(struct pci_dev *dev, struct hv_interrupt_entry *old_entry); static void hv_irq_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) { struct msi_desc *msidesc; struct pci_dev *dev; struct hv_interrupt_entry out_entry, *stored_entry; struct irq_cfg *cfg = irqd_cfg(data); cpumask_t *affinity; int cpu; u64 status; msidesc = irq_data_get_msi_desc(data); dev = msi_desc_to_pci_dev(msidesc); if (!cfg) { pr_debug("%s: cfg is NULL", __func__); return; } affinity = irq_data_get_effective_affinity_mask(data); cpu = cpumask_first_and(affinity, cpu_online_mask); if (data->chip_data) { /* * This interrupt is already mapped. Let's unmap first. * * We don't use retarget interrupt hypercalls here because * Microsoft Hypervisor doens't allow root to change the vector * or specify VPs outside of the set that is initially used * during mapping. */ stored_entry = data->chip_data; data->chip_data = NULL; status = hv_unmap_msi_interrupt(dev, stored_entry); kfree(stored_entry); if (status != HV_STATUS_SUCCESS) { pr_debug("%s: failed to unmap, status %lld", __func__, status); return; } } stored_entry = kzalloc(sizeof(*stored_entry), GFP_ATOMIC); if (!stored_entry) { pr_debug("%s: failed to allocate chip data\n", __func__); return; } status = hv_map_msi_interrupt(dev, cpu, cfg->vector, &out_entry); if (status != HV_STATUS_SUCCESS) { kfree(stored_entry); return; } *stored_entry = out_entry; data->chip_data = stored_entry; entry_to_msi_msg(&out_entry, msg); return; } static int hv_unmap_msi_interrupt(struct pci_dev *dev, struct hv_interrupt_entry *old_entry) { return hv_unmap_interrupt(hv_build_pci_dev_id(dev).as_uint64, old_entry); } static void hv_teardown_msi_irq_common(struct pci_dev *dev, struct msi_desc *msidesc, int irq) { u64 status; struct hv_interrupt_entry old_entry; struct irq_desc *desc; struct irq_data *data; struct msi_msg msg; desc = irq_to_desc(irq); if (!desc) { pr_debug("%s: no irq desc\n", __func__); return; } data = &desc->irq_data; if (!data) { pr_debug("%s: no irq data\n", __func__); return; } if (!data->chip_data) { pr_debug("%s: no chip data\n!", __func__); return; } old_entry = *(struct hv_interrupt_entry *)data->chip_data; entry_to_msi_msg(&old_entry, &msg); kfree(data->chip_data); data->chip_data = NULL; status = hv_unmap_msi_interrupt(dev, &old_entry); if (status != HV_STATUS_SUCCESS) { pr_err("%s: hypercall failed, status %lld\n", __func__, status); return; } } static void hv_msi_domain_free_irqs(struct irq_domain *domain, struct device *dev) { int i; struct msi_desc *entry; struct pci_dev *pdev; if (WARN_ON_ONCE(!dev_is_pci(dev))) return; pdev = to_pci_dev(dev); for_each_pci_msi_entry(entry, pdev) { if (entry->irq) { for (i = 0; i < entry->nvec_used; i++) { hv_teardown_msi_irq_common(pdev, entry, entry->irq + i); irq_domain_free_irqs(entry->irq + i, 1); } } } } /* * IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices, * which implement the MSI or MSI-X Capability Structure. */ static struct irq_chip hv_pci_msi_controller = { .name = "HV-PCI-MSI", .irq_unmask = pci_msi_unmask_irq, .irq_mask = pci_msi_mask_irq, .irq_ack = irq_chip_ack_parent, .irq_retrigger = irq_chip_retrigger_hierarchy, .irq_compose_msi_msg = hv_irq_compose_msi_msg, .irq_set_affinity = msi_domain_set_affinity, .flags = IRQCHIP_SKIP_SET_WAKE, }; static struct msi_domain_ops pci_msi_domain_ops = { .domain_free_irqs = hv_msi_domain_free_irqs, .msi_prepare = pci_msi_prepare, }; static struct msi_domain_info hv_pci_msi_domain_info = { .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | MSI_FLAG_PCI_MSIX, .ops = &pci_msi_domain_ops, .chip = &hv_pci_msi_controller, .handler = handle_edge_irq, .handler_name = "edge", }; struct irq_domain * __init hv_create_pci_msi_domain(void) { struct irq_domain *d = NULL; struct fwnode_handle *fn; fn = irq_domain_alloc_named_fwnode("HV-PCI-MSI"); if (fn) d = pci_msi_create_irq_domain(fn, &hv_pci_msi_domain_info, x86_vector_domain); /* No point in going further if we can't get an irq domain */ BUG_ON(!d); return d; } #endif /* CONFIG_PCI_MSI */ int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *entry) { union hv_device_id device_id; device_id.as_uint64 = 0; device_id.device_type = HV_DEVICE_TYPE_IOAPIC; device_id.ioapic.ioapic_id = (u8)ioapic_id; return hv_unmap_interrupt(device_id.as_uint64, entry); } EXPORT_SYMBOL_GPL(hv_unmap_ioapic_interrupt); int hv_map_ioapic_interrupt(int ioapic_id, bool level, int cpu, int vector, struct hv_interrupt_entry *entry) { union hv_device_id device_id; device_id.as_uint64 = 0; device_id.device_type = HV_DEVICE_TYPE_IOAPIC; device_id.ioapic.ioapic_id = (u8)ioapic_id; return hv_map_interrupt(device_id, level, cpu, vector, entry); } EXPORT_SYMBOL_GPL(hv_map_ioapic_interrupt);