order-list-attributes.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Functions corresponding to ordered list type attributes under
  4 * BIOS ORDERED LIST GUID for use with hp-bioscfg driver.
  5 *
  6 * Copyright (c) 2022 HP Development Company, L.P.
  7 */
  8
  9#include "bioscfg.h"
 10
 11GET_INSTANCE_ID(ordered_list);
 12
 13static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 14{
 15	int instance_id = get_ordered_list_instance_id(kobj);
 16
 17	if (instance_id < 0)
 18		return -EIO;
 19
 20	return sysfs_emit(buf, "%s\n",
 21			 bioscfg_drv.ordered_list_data[instance_id].current_value);
 22}
 23
 24static int replace_char_str(u8 *buffer, char *repl_char, char *repl_with)
 25{
 26	char *src = buffer;
 27	int buflen = strlen(buffer);
 28	int item;
 29
 30	if (buflen < 1)
 31		return -EINVAL;
 32
 33	for (item = 0; item < buflen; item++)
 34		if (src[item] == *repl_char)
 35			src[item] = *repl_with;
 36
 37	return 0;
 38}
 39
 40/**
 41 * validate_ordered_list_input() -
 42 * Validate input of current_value against possible values
 43 *
 44 * @instance: The instance on which input is validated
 45 * @buf: Input value
 46 */
 47static int validate_ordered_list_input(int instance, char *buf)
 48{
 49	/* validation is done by BIOS. This validation function will
 50	 * convert semicolon to commas. BIOS uses commas as
 51	 * separators when reporting ordered-list values.
 52	 */
 53	return replace_char_str(buf, SEMICOLON_SEP, COMMA_SEP);
 54}
 55
 56static void update_ordered_list_value(int instance, char *attr_value)
 57{
 58	struct ordered_list_data *ordered_list_data = &bioscfg_drv.ordered_list_data[instance];
 59
 60	strscpy(ordered_list_data->current_value, attr_value);
 61}
 62
 63ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, ordered_list);
 64static struct kobj_attribute ordered_list_display_name =
 65	__ATTR_RO(display_name);
 66
 67ATTRIBUTE_PROPERTY_STORE(current_value, ordered_list);
 68static struct kobj_attribute ordered_list_current_val =
 69	__ATTR_RW_MODE(current_value, 0644);
 70
 71ATTRIBUTE_VALUES_PROPERTY_SHOW(elements, ordered_list, SEMICOLON_SEP);
 72static struct kobj_attribute ordered_list_elements_val =
 73	__ATTR_RO(elements);
 74
 75static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
 76			 char *buf)
 77{
 78	return sysfs_emit(buf, "ordered-list\n");
 79}
 80
 81static struct kobj_attribute ordered_list_type =
 82	__ATTR_RO(type);
 83
 84static struct attribute *ordered_list_attrs[] = {
 85	&common_display_langcode.attr,
 86	&ordered_list_display_name.attr,
 87	&ordered_list_current_val.attr,
 88	&ordered_list_elements_val.attr,
 89	&ordered_list_type.attr,
 90	NULL
 91};
 92
 93static const struct attribute_group ordered_list_attr_group = {
 94	.attrs = ordered_list_attrs,
 95};
 96
 97int hp_alloc_ordered_list_data(void)
 98{
 99	bioscfg_drv.ordered_list_instances_count =
100		hp_get_instance_count(HP_WMI_BIOS_ORDERED_LIST_GUID);
101	bioscfg_drv.ordered_list_data = kcalloc(bioscfg_drv.ordered_list_instances_count,
102						sizeof(*bioscfg_drv.ordered_list_data),
103						GFP_KERNEL);
104	if (!bioscfg_drv.ordered_list_data) {
105		bioscfg_drv.ordered_list_instances_count = 0;
106		return -ENOMEM;
107	}
108	return 0;
109}
110
111/* Expected Values types associated with each element */
112static const acpi_object_type expected_order_types[] = {
113	[NAME]	= ACPI_TYPE_STRING,
114	[VALUE] = ACPI_TYPE_STRING,
115	[PATH] = ACPI_TYPE_STRING,
116	[IS_READONLY] = ACPI_TYPE_INTEGER,
117	[DISPLAY_IN_UI] = ACPI_TYPE_INTEGER,
118	[REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER,
119	[SEQUENCE] = ACPI_TYPE_INTEGER,
120	[PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER,
121	[PREREQUISITES] = ACPI_TYPE_STRING,
122	[SECURITY_LEVEL] = ACPI_TYPE_INTEGER,
123	[ORD_LIST_SIZE] = ACPI_TYPE_INTEGER,
124	[ORD_LIST_ELEMENTS] = ACPI_TYPE_STRING,
125};
126
127static int hp_populate_ordered_list_elements_from_package(union acpi_object *order_obj,
128							  int order_obj_count,
129							  int instance_id)
130{
131	char *str_value = NULL;
132	int value_len = 0;
133	int ret;
134	u32 size;
135	u32 int_value = 0;
136	int elem;
137	int olist_elem;
138	int reqs;
139	int eloc;
140	char *tmpstr = NULL;
141	char *part_tmp = NULL;
142	int tmp_len = 0;
143	char *part = NULL;
144	struct ordered_list_data *ordered_list_data = &bioscfg_drv.ordered_list_data[instance_id];
145
146	if (!order_obj)
147		return -EINVAL;
148
149	for (elem = 1, eloc = 1; eloc < ORD_ELEM_CNT; elem++, eloc++) {
150
151		switch (order_obj[elem].type) {
152		case ACPI_TYPE_STRING:
153			if (elem != PREREQUISITES && elem != ORD_LIST_ELEMENTS) {
154				ret = hp_convert_hexstr_to_str(order_obj[elem].string.pointer,
155							       order_obj[elem].string.length,
156							       &str_value, &value_len);
157				if (ret)
158					continue;
159			}
160			break;
161		case ACPI_TYPE_INTEGER:
162			int_value = (u32)order_obj[elem].integer.value;
163			break;
164		default:
165			pr_warn("Unsupported object type [%d]\n", order_obj[elem].type);
166			continue;
167		}
168
169		/* Check that both expected and read object type match */
170		if (expected_order_types[eloc] != order_obj[elem].type) {
171			pr_err("Error expected type %d for elem %d, but got type %d instead\n",
172			       expected_order_types[eloc], elem, order_obj[elem].type);
173			kfree(str_value);
174			return -EIO;
175		}
176
177		/* Assign appropriate element value to corresponding field*/
178		switch (eloc) {
179		case VALUE:
180			strscpy(ordered_list_data->current_value, str_value);
181			replace_char_str(ordered_list_data->current_value, COMMA_SEP, SEMICOLON_SEP);
182			break;
183		case PATH:
184			strscpy(ordered_list_data->common.path, str_value);
185			break;
186		case IS_READONLY:
187			ordered_list_data->common.is_readonly = int_value;
188			break;
189		case DISPLAY_IN_UI:
190			ordered_list_data->common.display_in_ui = int_value;
191			break;
192		case REQUIRES_PHYSICAL_PRESENCE:
193			ordered_list_data->common.requires_physical_presence = int_value;
194			break;
195		case SEQUENCE:
196			ordered_list_data->common.sequence = int_value;
197			break;
198		case PREREQUISITES_SIZE:
199			if (int_value > MAX_PREREQUISITES_SIZE) {
200				pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n");
201				int_value = MAX_PREREQUISITES_SIZE;
202			}
203			ordered_list_data->common.prerequisites_size = int_value;
204
205			/*
206			 * This step is needed to keep the expected
207			 * element list pointing to the right obj[elem].type
208			 * when the size is zero. PREREQUISITES
209			 * object is omitted by BIOS when the size is
210			 * zero.
211			 */
212			if (int_value == 0)
213				eloc++;
214			break;
215		case PREREQUISITES:
216			size = min_t(u32, ordered_list_data->common.prerequisites_size,
217				     MAX_PREREQUISITES_SIZE);
218			for (reqs = 0; reqs < size; reqs++) {
219				if (elem + reqs >= order_obj_count) {
220					pr_err("Error elem-objects package is too small\n");
221					return -EINVAL;
222				}
223
224				ret = hp_convert_hexstr_to_str(order_obj[elem + reqs].string.pointer,
225							       order_obj[elem + reqs].string.length,
226							       &str_value, &value_len);
227
228				if (ret)
229					continue;
230
231				strscpy(ordered_list_data->common.prerequisites[reqs], str_value);
232
233				kfree(str_value);
234				str_value = NULL;
235			}
236			break;
237
238		case SECURITY_LEVEL:
239			ordered_list_data->common.security_level = int_value;
240			break;
241
242		case ORD_LIST_SIZE:
243			if (int_value > MAX_ELEMENTS_SIZE) {
244				pr_warn("Order List size value exceeded the maximum number of elements supported or data may be malformed\n");
245				int_value = MAX_ELEMENTS_SIZE;
246			}
247			ordered_list_data->elements_size = int_value;
248
249			/*
250			 * This step is needed to keep the expected
251			 * element list pointing to the right obj[elem].type
252			 * when the size is zero. ORD_LIST_ELEMENTS
253			 * object is omitted by BIOS when the size is
254			 * zero.
255			 */
256			if (int_value == 0)
257				eloc++;
258			break;
259		case ORD_LIST_ELEMENTS:
260
261			/*
262			 * Ordered list data is stored in hex and comma separated format
263			 * Convert the data and split it to show each element
264			 */
265			ret = hp_convert_hexstr_to_str(str_value, value_len, &tmpstr, &tmp_len);
266			if (ret)
267				goto exit_list;
268
269			part_tmp = tmpstr;
270			part = strsep(&part_tmp, COMMA_SEP);
271
272			for (olist_elem = 0; olist_elem < MAX_ELEMENTS_SIZE && part; olist_elem++) {
273				strscpy(ordered_list_data->elements[olist_elem], part);
274				part = strsep(&part_tmp, COMMA_SEP);
275			}
276			ordered_list_data->elements_size = olist_elem;
277
278			kfree(str_value);
279			str_value = NULL;
280			break;
281		default:
282			pr_warn("Invalid element: %d found in Ordered_List attribute or data may be malformed\n", elem);
283			break;
284		}
285		kfree(tmpstr);
286		tmpstr = NULL;
287		kfree(str_value);
288		str_value = NULL;
289	}
290
291exit_list:
292	kfree(tmpstr);
293	kfree(str_value);
294	return 0;
295}
296
297/**
298 * hp_populate_ordered_list_package_data() -
299 * Populate all properties of an instance under ordered_list attribute
300 *
301 * @order_obj: ACPI object with ordered_list data
302 * @instance_id: The instance to enumerate
303 * @attr_name_kobj: The parent kernel object
304 */
305int hp_populate_ordered_list_package_data(union acpi_object *order_obj, int instance_id,
306					  struct kobject *attr_name_kobj)
307{
308	struct ordered_list_data *ordered_list_data = &bioscfg_drv.ordered_list_data[instance_id];
309
310	ordered_list_data->attr_name_kobj = attr_name_kobj;
311
312	hp_populate_ordered_list_elements_from_package(order_obj,
313						       order_obj->package.count,
314						       instance_id);
315	hp_update_attribute_permissions(ordered_list_data->common.is_readonly,
316					&ordered_list_current_val);
317	hp_friendly_user_name_update(ordered_list_data->common.path,
318				     attr_name_kobj->name,
319				     ordered_list_data->common.display_name,
320				     sizeof(ordered_list_data->common.display_name));
321	return sysfs_create_group(attr_name_kobj, &ordered_list_attr_group);
322}
323
324static int hp_populate_ordered_list_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size,
325							 int instance_id)
326{
327	int values;
328	struct ordered_list_data *ordered_list_data = &bioscfg_drv.ordered_list_data[instance_id];
329	int ret = 0;
330
331	/*
332	 * Only data relevant to this driver and its functionality is
333	 * read. BIOS defines the order in which each * element is
334	 * read. Element 0 data is not relevant to this
335	 * driver hence it is ignored. For clarity, all element names
336	 * (DISPLAY_IN_UI) which defines the order in which is read
337	 * and the name matches the variable where the data is stored.
338	 *
339	 * In earlier implementation, reported errors were ignored
340	 * causing the data to remain uninitialized. It is not
341	 * possible to determine if data read from BIOS is valid or
342	 * not. It is for this reason functions may return a error
343	 * without validating the data itself.
344	 */
345
346	// VALUE:
347	ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size, ordered_list_data->current_value,
348					sizeof(ordered_list_data->current_value));
349	if (ret < 0)
350		goto buffer_exit;
351
352	replace_char_str(ordered_list_data->current_value, COMMA_SEP, SEMICOLON_SEP);
353
354	// COMMON:
355	ret = hp_get_common_data_from_buffer(&buffer_ptr, buffer_size,
356					     &ordered_list_data->common);
357	if (ret < 0)
358		goto buffer_exit;
359
360	// ORD_LIST_SIZE:
361	ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size,
362					 &ordered_list_data->elements_size);
363
364	if (ordered_list_data->elements_size > MAX_ELEMENTS_SIZE) {
365		/* Report a message and limit elements size to maximum value */
366		pr_warn("Ordered List size value exceeded the maximum number of elements supported or data may be malformed\n");
367		ordered_list_data->elements_size = MAX_ELEMENTS_SIZE;
368	}
369
370	// ORD_LIST_ELEMENTS:
371	for (values = 0; values < ordered_list_data->elements_size; values++) {
372		ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size,
373						ordered_list_data->elements[values],
374						sizeof(ordered_list_data->elements[values]));
375		if (ret < 0)
376			break;
377	}
378
379buffer_exit:
380	return ret;
381}
382
383/**
384 * hp_populate_ordered_list_buffer_data() - Populate all properties of an
385 * instance under ordered list attribute
386 *
387 * @buffer_ptr: Buffer pointer
388 * @buffer_size: Buffer size
389 * @instance_id: The instance to enumerate
390 * @attr_name_kobj: The parent kernel object
391 */
392int hp_populate_ordered_list_buffer_data(u8 *buffer_ptr, u32 *buffer_size, int instance_id,
393					 struct kobject *attr_name_kobj)
394{
395	struct ordered_list_data *ordered_list_data = &bioscfg_drv.ordered_list_data[instance_id];
396	int ret = 0;
397
398	ordered_list_data->attr_name_kobj = attr_name_kobj;
399
400	/* Populate ordered list elements */
401	ret = hp_populate_ordered_list_elements_from_buffer(buffer_ptr, buffer_size,
402							    instance_id);
403	if (ret < 0)
404		return ret;
405
406	hp_update_attribute_permissions(ordered_list_data->common.is_readonly,
407					&ordered_list_current_val);
408	hp_friendly_user_name_update(ordered_list_data->common.path,
409				     attr_name_kobj->name,
410				     ordered_list_data->common.display_name,
411				     sizeof(ordered_list_data->common.display_name));
412
413	return sysfs_create_group(attr_name_kobj, &ordered_list_attr_group);
414}
415
416/**
417 * hp_exit_ordered_list_attributes() - Clear all attribute data
418 *
419 * Clears all data allocated for this group of attributes
420 */
421void hp_exit_ordered_list_attributes(void)
422{
423	int instance_id;
424
425	for (instance_id = 0; instance_id < bioscfg_drv.ordered_list_instances_count;
426	     instance_id++) {
427		struct kobject *attr_name_kobj =
428			bioscfg_drv.ordered_list_data[instance_id].attr_name_kobj;
429
430		if (attr_name_kobj)
431			sysfs_remove_group(attr_name_kobj,
432					   &ordered_list_attr_group);
433	}
434	bioscfg_drv.ordered_list_instances_count = 0;
435
436	kfree(bioscfg_drv.ordered_list_data);
437	bioscfg_drv.ordered_list_data = NULL;
438}