Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 651 insertions, 0 deletions

diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c
new file mode 100644
index 000000000..c5434b998
--- /dev/null
+++ b/drivers/acpi/device_sysfs.c
@@ -0,0 +1,651 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * drivers/acpi/device_sysfs.c - ACPI device sysfs attributes and modalias.
+ *
+ * Copyright (C) 2015, Intel Corp.
+ * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/nls.h>
+
+#include "internal.h"
+
+static ssize_t acpi_object_path(acpi_handle handle, char *buf)
+{
+	struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
+	int result;
+
+	result = acpi_get_name(handle, ACPI_FULL_PATHNAME, &path);
+	if (result)
+		return result;
+
+	result = sysfs_emit(buf, "%s\n", (char *)path.pointer);
+	kfree(path.pointer);
+	return result;
+}
+
+struct acpi_data_node_attr {
+	struct attribute attr;
+	ssize_t (*show)(struct acpi_data_node *, char *);
+	ssize_t (*store)(struct acpi_data_node *, const char *, size_t count);
+};
+
+#define DATA_NODE_ATTR(_name)			\
+	static struct acpi_data_node_attr data_node_##_name =	\
+		__ATTR(_name, 0444, data_node_show_##_name, NULL)
+
+static ssize_t data_node_show_path(struct acpi_data_node *dn, char *buf)
+{
+	return dn->handle ? acpi_object_path(dn->handle, buf) : 0;
+}
+
+DATA_NODE_ATTR(path);
+
+static struct attribute *acpi_data_node_default_attrs[] = {
+	&data_node_path.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(acpi_data_node_default);
+
+#define to_data_node(k) container_of(k, struct acpi_data_node, kobj)
+#define to_attr(a) container_of(a, struct acpi_data_node_attr, attr)
+
+static ssize_t acpi_data_node_attr_show(struct kobject *kobj,
+					struct attribute *attr, char *buf)
+{
+	struct acpi_data_node *dn = to_data_node(kobj);
+	struct acpi_data_node_attr *dn_attr = to_attr(attr);
+
+	return dn_attr->show ? dn_attr->show(dn, buf) : -ENXIO;
+}
+
+static const struct sysfs_ops acpi_data_node_sysfs_ops = {
+	.show	= acpi_data_node_attr_show,
+};
+
+static void acpi_data_node_release(struct kobject *kobj)
+{
+	struct acpi_data_node *dn = to_data_node(kobj);
+
+	complete(&dn->kobj_done);
+}
+
+static const struct kobj_type acpi_data_node_ktype = {
+	.sysfs_ops = &acpi_data_node_sysfs_ops,
+	.default_groups = acpi_data_node_default_groups,
+	.release = acpi_data_node_release,
+};
+
+static void acpi_expose_nondev_subnodes(struct kobject *kobj,
+					struct acpi_device_data *data)
+{
+	struct list_head *list = &data->subnodes;
+	struct acpi_data_node *dn;
+
+	if (list_empty(list))
+		return;
+
+	list_for_each_entry(dn, list, sibling) {
+		int ret;
+
+		init_completion(&dn->kobj_done);
+		ret = kobject_init_and_add(&dn->kobj, &acpi_data_node_ktype,
+					   kobj, "%s", dn->name);
+		if (!ret)
+			acpi_expose_nondev_subnodes(&dn->kobj, &dn->data);
+		else if (dn->handle)
+			acpi_handle_err(dn->handle, "Failed to expose (%d)\n", ret);
+	}
+}
+
+static void acpi_hide_nondev_subnodes(struct acpi_device_data *data)
+{
+	struct list_head *list = &data->subnodes;
+	struct acpi_data_node *dn;
+
+	if (list_empty(list))
+		return;
+
+	list_for_each_entry_reverse(dn, list, sibling) {
+		acpi_hide_nondev_subnodes(&dn->data);
+		kobject_put(&dn->kobj);
+	}
+}
+
+/**
+ * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent
+ * @acpi_dev: ACPI device object.
+ * @modalias: Buffer to print into.
+ * @size: Size of the buffer.
+ *
+ * Creates hid/cid(s) string needed for modalias and uevent
+ * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
+ * char *modalias: "acpi:IBM0001:ACPI0001"
+ * Return: 0: no _HID and no _CID
+ *         -EINVAL: output error
+ *         -ENOMEM: output is truncated
+ */
+static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalias,
+			       int size)
+{
+	int len;
+	int count;
+	struct acpi_hardware_id *id;
+
+	/* Avoid unnecessarily loading modules for non present devices. */
+	if (!acpi_device_is_present(acpi_dev))
+		return 0;
+
+	/*
+	 * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should
+	 * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the
+	 * device's list.
+	 */
+	count = 0;
+	list_for_each_entry(id, &acpi_dev->pnp.ids, list)
+		if (strcmp(id->id, ACPI_DT_NAMESPACE_HID))
+			count++;
+
+	if (!count)
+		return 0;
+
+	len = snprintf(modalias, size, "acpi:");
+	if (len >= size)
+		return -ENOMEM;
+
+	size -= len;
+
+	list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
+		if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID))
+			continue;
+
+		count = snprintf(&modalias[len], size, "%s:", id->id);
+
+		if (count >= size)
+			return -ENOMEM;
+
+		len += count;
+		size -= count;
+	}
+
+	return len;
+}
+
+/**
+ * create_of_modalias - Creates DT compatible string for modalias and uevent
+ * @acpi_dev: ACPI device object.
+ * @modalias: Buffer to print into.
+ * @size: Size of the buffer.
+ *
+ * Expose DT compatible modalias as of:NnameTCcompatible.  This function should
+ * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of
+ * ACPI/PNP IDs.
+ */
+static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias,
+			      int size)
+{
+	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
+	const union acpi_object *of_compatible, *obj;
+	acpi_status status;
+	int len, count;
+	int i, nval;
+	char *c;
+
+	status = acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	/* DT strings are all in lower case */
+	for (c = buf.pointer; *c != '\0'; c++)
+		*c = tolower(*c);
+
+	len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer);
+	ACPI_FREE(buf.pointer);
+
+	if (len >= size)
+		return -ENOMEM;
+
+	size -= len;
+
+	of_compatible = acpi_dev->data.of_compatible;
+	if (of_compatible->type == ACPI_TYPE_PACKAGE) {
+		nval = of_compatible->package.count;
+		obj = of_compatible->package.elements;
+	} else { /* Must be ACPI_TYPE_STRING. */
+		nval = 1;
+		obj = of_compatible;
+	}
+	for (i = 0; i < nval; i++, obj++) {
+		count = snprintf(&modalias[len], size, "C%s",
+				 obj->string.pointer);
+
+		if (count >= size)
+			return -ENOMEM;
+
+		len += count;
+		size -= count;
+	}
+
+	return len;
+}
+
+int __acpi_device_uevent_modalias(const struct acpi_device *adev,
+				  struct kobj_uevent_env *env)
+{
+	int len;
+
+	if (!adev)
+		return -ENODEV;
+
+	if (list_empty(&adev->pnp.ids))
+		return 0;
+
+	if (add_uevent_var(env, "MODALIAS="))
+		return -ENOMEM;
+
+	if (adev->data.of_compatible)
+		len = create_of_modalias(adev, &env->buf[env->buflen - 1],
+					 sizeof(env->buf) - env->buflen);
+	else
+		len = create_pnp_modalias(adev, &env->buf[env->buflen - 1],
+					  sizeof(env->buf) - env->buflen);
+	if (len < 0)
+		return len;
+
+	env->buflen += len;
+
+	return 0;
+}
+
+/**
+ * acpi_device_uevent_modalias - uevent modalias for ACPI-enumerated devices.
+ * @dev: Struct device to get ACPI device node.
+ * @env: Environment variables of the kobject uevent.
+ *
+ * Create the uevent modalias field for ACPI-enumerated devices.
+ *
+ * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with
+ * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001".
+ */
+int acpi_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env)
+{
+	return __acpi_device_uevent_modalias(acpi_companion_match(dev), env);
+}
+EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
+
+static int __acpi_device_modalias(const struct acpi_device *adev, char *buf, int size)
+{
+	int len, count;
+
+	if (!adev)
+		return -ENODEV;
+
+	if (list_empty(&adev->pnp.ids))
+		return 0;
+
+	len = create_pnp_modalias(adev, buf, size - 1);
+	if (len < 0) {
+		return len;
+	} else if (len > 0) {
+		buf[len++] = '\n';
+		size -= len;
+	}
+	if (!adev->data.of_compatible)
+		return len;
+
+	count = create_of_modalias(adev, buf + len, size - 1);
+	if (count < 0) {
+		return count;
+	} else if (count > 0) {
+		len += count;
+		buf[len++] = '\n';
+	}
+
+	return len;
+}
+
+/**
+ * acpi_device_modalias - modalias sysfs attribute for ACPI-enumerated devices.
+ * @dev: Struct device to get ACPI device node.
+ * @buf: The buffer to save pnp_modalias and of_modalias.
+ * @size: Size of buffer.
+ *
+ * Create the modalias sysfs attribute for ACPI-enumerated devices.
+ *
+ * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with
+ * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001".
+ */
+int acpi_device_modalias(struct device *dev, char *buf, int size)
+{
+	return __acpi_device_modalias(acpi_companion_match(dev), buf, size);
+}
+EXPORT_SYMBOL_GPL(acpi_device_modalias);
+
+static ssize_t
+modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return __acpi_device_modalias(to_acpi_device(dev), buf, 1024);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static ssize_t real_power_state_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct acpi_device *adev = to_acpi_device(dev);
+	int state;
+	int ret;
+
+	ret = acpi_device_get_power(adev, &state);
+	if (ret)
+		return ret;
+
+	return sysfs_emit(buf, "%s\n", acpi_power_state_string(state));
+}
+
+static DEVICE_ATTR_RO(real_power_state);
+
+static ssize_t power_state_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct acpi_device *adev = to_acpi_device(dev);
+
+	return sysfs_emit(buf, "%s\n", acpi_power_state_string(adev->power.state));
+}
+
+static DEVICE_ATTR_RO(power_state);
+
+static ssize_t
+eject_store(struct device *d, struct device_attribute *attr,
+	    const char *buf, size_t count)
+{
+	struct acpi_device *acpi_device = to_acpi_device(d);
+	acpi_object_type not_used;
+	acpi_status status;
+
+	if (!count || buf[0] != '1')
+		return -EINVAL;
+
+	if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
+	    && !d->driver)
+		return -ENODEV;
+
+	status = acpi_get_type(acpi_device->handle, &not_used);
+	if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
+		return -ENODEV;
+
+	acpi_dev_get(acpi_device);
+	status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT);
+	if (ACPI_SUCCESS(status))
+		return count;
+
+	acpi_dev_put(acpi_device);
+	acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
+			  ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
+	return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
+}
+
+static DEVICE_ATTR_WO(eject);
+
+static ssize_t
+hid_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+
+	return sysfs_emit(buf, "%s\n", acpi_device_hid(acpi_dev));
+}
+static DEVICE_ATTR_RO(hid);
+
+static ssize_t cid_show(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	struct acpi_device_info *info = NULL;
+	ssize_t len = 0;
+
+	acpi_get_object_info(acpi_dev->handle, &info);
+	if (!info)
+		return 0;
+
+	if (info->valid & ACPI_VALID_CID) {
+		struct acpi_pnp_device_id_list *cid_list = &info->compatible_id_list;
+		int i;
+
+		for (i = 0; i < cid_list->count - 1; i++)
+			len += sysfs_emit_at(buf, len, "%s,", cid_list->ids[i].string);
+
+		len += sysfs_emit_at(buf, len, "%s\n", cid_list->ids[i].string);
+	}
+
+	kfree(info);
+
+	return len;
+}
+static DEVICE_ATTR_RO(cid);
+
+static ssize_t uid_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+
+	return sysfs_emit(buf, "%s\n", acpi_device_uid(acpi_dev));
+}
+static DEVICE_ATTR_RO(uid);
+
+static ssize_t adr_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+
+	if (acpi_dev->pnp.bus_address > U32_MAX)
+		return sysfs_emit(buf, "0x%016llx\n", acpi_dev->pnp.bus_address);
+	else
+		return sysfs_emit(buf, "0x%08llx\n", acpi_dev->pnp.bus_address);
+}
+static DEVICE_ATTR_RO(adr);
+
+static ssize_t path_show(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+
+	return acpi_object_path(acpi_dev->handle, buf);
+}
+static DEVICE_ATTR_RO(path);
+
+/* sysfs file that shows description text from the ACPI _STR method */
+static ssize_t description_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
+	union acpi_object *str_obj;
+	acpi_status status;
+	int result;
+
+	status = acpi_evaluate_object_typed(acpi_dev->handle, "_STR",
+					    NULL, &buffer,
+					    ACPI_TYPE_BUFFER);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	str_obj = buffer.pointer;
+
+	/*
+	 * The _STR object contains a Unicode identifier for a device.
+	 * We need to convert to utf-8 so it can be displayed.
+	 */
+	result = utf16s_to_utf8s(
+		(wchar_t *)str_obj->buffer.pointer,
+		str_obj->buffer.length,
+		UTF16_LITTLE_ENDIAN, buf,
+		PAGE_SIZE - 1);
+
+	buf[result++] = '\n';
+
+	ACPI_FREE(str_obj);
+
+	return result;
+}
+static DEVICE_ATTR_RO(description);
+
+static ssize_t
+sun_show(struct device *dev, struct device_attribute *attr,
+	 char *buf)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	acpi_status status;
+	unsigned long long sun;
+
+	status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	return sysfs_emit(buf, "%llu\n", sun);
+}
+static DEVICE_ATTR_RO(sun);
+
+static ssize_t
+hrv_show(struct device *dev, struct device_attribute *attr,
+	 char *buf)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	acpi_status status;
+	unsigned long long hrv;
+
+	status = acpi_evaluate_integer(acpi_dev->handle, "_HRV", NULL, &hrv);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	return sysfs_emit(buf, "%llu\n", hrv);
+}
+static DEVICE_ATTR_RO(hrv);
+
+static ssize_t status_show(struct device *dev, struct device_attribute *attr,
+				char *buf)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	acpi_status status;
+	unsigned long long sta;
+
+	status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	return sysfs_emit(buf, "%llu\n", sta);
+}
+static DEVICE_ATTR_RO(status);
+
+static struct attribute *acpi_attrs[] = {
+	&dev_attr_path.attr,
+	&dev_attr_hid.attr,
+	&dev_attr_cid.attr,
+	&dev_attr_modalias.attr,
+	&dev_attr_description.attr,
+	&dev_attr_adr.attr,
+	&dev_attr_uid.attr,
+	&dev_attr_sun.attr,
+	&dev_attr_hrv.attr,
+	&dev_attr_status.attr,
+	&dev_attr_eject.attr,
+	&dev_attr_power_state.attr,
+	&dev_attr_real_power_state.attr,
+	NULL
+};
+
+static bool acpi_show_attr(struct acpi_device *dev, const struct device_attribute *attr)
+{
+	/*
+	 * Devices gotten from FADT don't have a "path" attribute
+	 */
+	if (attr == &dev_attr_path)
+		return dev->handle;
+
+	if (attr == &dev_attr_hid || attr == &dev_attr_modalias)
+		return !list_empty(&dev->pnp.ids);
+
+	if (attr == &dev_attr_description)
+		return acpi_has_method(dev->handle, "_STR");
+
+	if (attr == &dev_attr_adr)
+		return dev->pnp.type.bus_address;
+
+	if (attr == &dev_attr_uid)
+		return acpi_device_uid(dev);
+
+	if (attr == &dev_attr_sun)
+		return acpi_has_method(dev->handle, "_SUN");
+
+	if (attr == &dev_attr_hrv)
+		return acpi_has_method(dev->handle, "_HRV");
+
+	if (attr == &dev_attr_status)
+		return acpi_has_method(dev->handle, "_STA");
+
+	if (attr == &dev_attr_cid)
+		return acpi_has_method(dev->handle, "_CID");
+
+	/*
+	 * If device has _EJ0, 'eject' file is created that is used to trigger
+	 * hot-removal function from userland.
+	 */
+	if (attr == &dev_attr_eject)
+		return acpi_has_method(dev->handle, "_EJ0");
+
+	if (attr == &dev_attr_power_state)
+		return dev->flags.power_manageable;
+
+	if (attr == &dev_attr_real_power_state)
+		return dev->flags.power_manageable && dev->power.flags.power_resources;
+
+	dev_warn_once(&dev->dev, "Unexpected attribute: %s\n", attr->attr.name);
+	return false;
+}
+
+static umode_t acpi_attr_is_visible(struct kobject *kobj,
+				    struct attribute *attr,
+				    int attrno)
+{
+	struct acpi_device *dev = to_acpi_device(kobj_to_dev(kobj));
+
+	if (acpi_show_attr(dev, container_of(attr, struct device_attribute, attr)))
+		return attr->mode;
+	else
+		return 0;
+}
+
+static const struct attribute_group acpi_group = {
+	.attrs = acpi_attrs,
+	.is_visible = acpi_attr_is_visible,
+};
+
+const struct attribute_group *acpi_groups[] = {
+	&acpi_group,
+	NULL
+};
+
+/**
+ * acpi_device_setup_files - Create sysfs attributes of an ACPI device.
+ * @dev: ACPI device object.
+ */
+void acpi_device_setup_files(struct acpi_device *dev)
+{
+	acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data);
+}
+
+/**
+ * acpi_device_remove_files - Remove sysfs attributes of an ACPI device.
+ * @dev: ACPI device object.
+ */
+void acpi_device_remove_files(struct acpi_device *dev)
+{
+	acpi_hide_nondev_subnodes(&dev->data);
+}