diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-firmware-acpi | 10 | ||||
| -rw-r--r-- | drivers/acpi/internal.h | 2 | ||||
| -rw-r--r-- | drivers/acpi/scan.c | 84 | ||||
| -rw-r--r-- | drivers/acpi/sysfs.c | 31 | ||||
| -rw-r--r-- | include/acpi/acpi_bus.h | 1 |
5 files changed, 128 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-firmware-acpi b/Documentation/ABI/testing/sysfs-firmware-acpi index ce9bee9..b4436cca 100644 --- a/Documentation/ABI/testing/sysfs-firmware-acpi +++ b/Documentation/ABI/testing/sysfs-firmware-acpi @@ -44,6 +44,16 @@ Description: or 0 (unset). Attempts to write any other values to it will cause -EINVAL to be returned. +What: /sys/firmware/acpi/hotplug/force_remove +Date: May 2013 +Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> +Description: + The number in this file (0 or 1) determines whether (1) or not + (0) the ACPI subsystem will allow devices to be hot-removed even + if they cannot be put offline gracefully (from the kernel's + viewpoint). That number can be changed by writing a boolean + value to this file. + What: /sys/firmware/acpi/interrupts/ Date: February 2008 Contact: Len Brown <lenb@kernel.org> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 6f1afd9..4548f0a 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -47,6 +47,8 @@ void acpi_memory_hotplug_init(void); static inline void acpi_memory_hotplug_init(void) {} #endif +extern bool acpi_force_hot_remove; + void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug, const char *name); int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler, diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index fe158fd..4fd3920 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -27,6 +27,12 @@ extern struct acpi_device *acpi_root; #define ACPI_IS_ROOT_DEVICE(device) (!(device)->parent) +/* + * If set, devices will be hot-removed even if they cannot be put offline + * gracefully (from the kernel's standpoint). + */ +bool acpi_force_hot_remove; + static const char *dummy_hid = "device"; static LIST_HEAD(acpi_device_list); @@ -120,6 +126,59 @@ acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, cha } static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL); +static acpi_status acpi_bus_offline_companions(acpi_handle handle, u32 lvl, + void *data, void **ret_p) +{ + struct acpi_device *device = NULL; + struct acpi_device_physical_node *pn; + acpi_status status = AE_OK; + + if (acpi_bus_get_device(handle, &device)) + return AE_OK; + + mutex_lock(&device->physical_node_lock); + + list_for_each_entry(pn, &device->physical_node_list, node) { + int ret; + + ret = device_offline(pn->dev); + if (acpi_force_hot_remove) + continue; + + if (ret < 0) { + status = AE_ERROR; + break; + } + pn->put_online = !ret; + } + + mutex_unlock(&device->physical_node_lock); + + return status; +} + +static acpi_status acpi_bus_online_companions(acpi_handle handle, u32 lvl, + void *data, void **ret_p) +{ + struct acpi_device *device = NULL; + struct acpi_device_physical_node *pn; + + if (acpi_bus_get_device(handle, &device)) + return AE_OK; + + mutex_lock(&device->physical_node_lock); + + list_for_each_entry(pn, &device->physical_node_list, node) + if (pn->put_online) { + device_online(pn->dev); + pn->put_online = false; + } + + mutex_unlock(&device->physical_node_lock); + + return AE_OK; +} + static int acpi_scan_hot_remove(struct acpi_device *device) { acpi_handle handle = device->handle; @@ -136,10 +195,33 @@ static int acpi_scan_hot_remove(struct acpi_device *device) return -EINVAL; } + lock_device_hotplug(); + + status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, + NULL, acpi_bus_offline_companions, NULL, + NULL); + if (ACPI_SUCCESS(status) || acpi_force_hot_remove) + status = acpi_bus_offline_companions(handle, 0, NULL, NULL); + + if (ACPI_FAILURE(status) && !acpi_force_hot_remove) { + acpi_bus_online_companions(handle, 0, NULL, NULL); + acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, + acpi_bus_online_companions, NULL, NULL, + NULL); + + unlock_device_hotplug(); + + put_device(&device->dev); + return -EBUSY; + } + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Hot-removing device %s...\n", dev_name(&device->dev))); acpi_bus_trim(device); + + unlock_device_hotplug(); + /* Device node has been unregistered. */ put_device(&device->dev); device = NULL; @@ -236,6 +318,7 @@ static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source) int error; mutex_lock(&acpi_scan_lock); + lock_device_hotplug(); acpi_bus_get_device(handle, &device); if (device) { @@ -259,6 +342,7 @@ static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source) kobject_uevent(&device->dev.kobj, KOBJ_ONLINE); out: + unlock_device_hotplug(); acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL); mutex_unlock(&acpi_scan_lock); } diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c index fcae5fa..5c5d162 100644 --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -780,6 +780,33 @@ void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug, pr_err(PREFIX "Unable to add hotplug profile '%s'\n", name); } +static ssize_t force_remove_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", !!acpi_force_hot_remove); +} + +static ssize_t force_remove_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t size) +{ + bool val; + int ret; + + ret = strtobool(buf, &val); + if (ret < 0) + return ret; + + lock_device_hotplug(); + acpi_force_hot_remove = val; + unlock_device_hotplug(); + return size; +} + +static const struct kobj_attribute force_remove_attr = + __ATTR(force_remove, S_IRUGO | S_IWUSR, force_remove_show, + force_remove_store); + int __init acpi_sysfs_init(void) { int result; @@ -789,6 +816,10 @@ int __init acpi_sysfs_init(void) return result; hotplug_kobj = kobject_create_and_add("hotplug", acpi_kobj); + result = sysfs_create_file(hotplug_kobj, &force_remove_attr.attr); + if (result) + return result; + result = sysfs_create_file(acpi_kobj, &pm_profile_attr.attr); return result; } diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index 98db31d..4d5d3e7 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -286,6 +286,7 @@ struct acpi_device_physical_node { u8 node_id; struct list_head node; struct device *dev; + bool put_online:1; }; /* set maximum of physical nodes to 32 for expansibility */ |
