From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rui Wang Subject: [PATCH V4 1/3] x86/ioapic: Support hot-removal of IOAPICs present during boot Date: Wed, 22 Jun 2016 15:40:19 +0800 Message-ID: <1466581219-20538-1-git-send-email-rui.y.wang@intel.com> References: <20160616170958.GA7250@localhost> Return-path: In-Reply-To: <20160616170958.GA7250@localhost> Sender: linux-pci-owner@vger.kernel.org To: helgaas@kernel.org Cc: tglx@linutronix.de, rjw@rjwysocki.net, tony.luck@intel.com, bhelgaas@google.com, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, rui.y.wang@intel.com List-Id: linux-acpi@vger.kernel.org v4: Add comments explaining when to call acpi_ioapic_add(). v3: Previous versions break mips. This version fixes it. IOAPICs present during system boot aren't added to ioapic_list, thus are unable to be hot-removed. Fix it by calling acpi_ioapic_add() during root bus enumeration. Signed-off-by: Rui Wang --- drivers/acpi/internal.h | 2 -- drivers/acpi/ioapic.c | 7 ++++--- drivers/acpi/pci_root.c | 13 ++++++++++++- drivers/pci/setup-bus.c | 7 ++++++- include/linux/acpi.h | 3 +++ 5 files changed, 25 insertions(+), 7 deletions(-) diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 27cc7fe..6d8e67e 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -40,10 +40,8 @@ int acpi_sysfs_init(void); void acpi_container_init(void); void acpi_memory_hotplug_init(void); #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC -int acpi_ioapic_add(struct acpi_pci_root *root); int acpi_ioapic_remove(struct acpi_pci_root *root); #else -static inline int acpi_ioapic_add(struct acpi_pci_root *root) { return 0; } static inline int acpi_ioapic_remove(struct acpi_pci_root *root) { return 0; } #endif #ifdef CONFIG_ACPI_DOCK diff --git a/drivers/acpi/ioapic.c b/drivers/acpi/ioapic.c index ccdc8db..0f272e2 100644 --- a/drivers/acpi/ioapic.c +++ b/drivers/acpi/ioapic.c @@ -189,16 +189,17 @@ exit: return AE_OK; } -int acpi_ioapic_add(struct acpi_pci_root *root) +int acpi_ioapic_add(acpi_handle root_handle) { acpi_status status, retval = AE_OK; - status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root->device->handle, + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root_handle, UINT_MAX, handle_ioapic_add, NULL, - root->device->handle, (void **)&retval); + root_handle, (void **)&retval); return ACPI_SUCCESS(status) && ACPI_SUCCESS(retval) ? 0 : -ENODEV; } +EXPORT_SYMBOL_GPL(acpi_ioapic_add); int acpi_ioapic_remove(struct acpi_pci_root *root) { diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index ae3fe4e..31e4440 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -614,7 +614,18 @@ static int acpi_pci_root_add(struct acpi_device *device, if (hotadd) { pcibios_resource_survey_bus(root->bus); pci_assign_unassigned_root_bus_resources(root->bus); - acpi_ioapic_add(root); + + /* + * This is only called for the hotadd case. For the boot-time + * case, we need to wait until after PCI initialization in + * order to deal with IOAPICs mapped in on a PCI BAR. + * + * This is currently x86-specific, because acpi_ioapic_add() + * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC. + * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC + * (see drivers/acpi/Kconfig). + */ + acpi_ioapic_add(root->device->handle); } pci_lock_rescan_remove(); diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 55641a3..0658921 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -25,6 +25,7 @@ #include #include #include +#include #include "pci.h" unsigned int pci_flags; @@ -1779,8 +1780,12 @@ void __init pci_assign_unassigned_resources(void) { struct pci_bus *root_bus; - list_for_each_entry(root_bus, &pci_root_buses, node) + list_for_each_entry(root_bus, &pci_root_buses, node) { pci_assign_unassigned_root_bus_resources(root_bus); +#ifdef CONFIG_X86 + acpi_ioapic_add(ACPI_HANDLE(root_bus->bridge)); +#endif + } } void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge) diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 288fac5..3ed22df 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -262,6 +262,9 @@ int acpi_unmap_cpu(int cpu); #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr); +int acpi_ioapic_add(acpi_handle root); +#else +static inline int acpi_ioapic_add(acpi_handle root) { return 0; } #endif int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base); -- 1.8.3.1