| Message ID | 20230420165454.9517-5-jorge.lopez2@hp.com (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
| Series | HP BIOSCFG driver | expand |
Hi Jorge, one thing I noticed: When I recommended to cut down the driver to a minimal feature set I meant the minimal feature set currently known to the kernel. This would *not* be sufficient for your HP-specific agent software. Just the standard type attributes, ordered-list and authentication. But in the end it would most probably still be a faster path to a solution that *does* include the full featureset of your requirements. Also when fixing review comments please try to fix them everywhere where applicable. Most comments affect many parts of the code. On 2023-04-20 11:54:44-0500, Jorge Lopez wrote: > --- > Based on the latest platform-drivers-x86.git/for-next > --- > .../x86/hp/hp-bioscfg/int-attributes.c | 474 ++++++++++++++++++ > 1 file changed, 474 insertions(+) > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > new file mode 100644 > index 000000000000..d8ee39dac3f9 > --- /dev/null > +++ b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > @@ -0,0 +1,474 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Functions corresponding to integer type attributes under > + * BIOS Enumeration GUID for use with hp-bioscfg driver. > + * > + * Copyright (c) 2022 Hewlett-Packard Inc. > + */ > + > +#include "bioscfg.h" > + > +GET_INSTANCE_ID(integer); > + > +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) > +{ > + int instance_id = get_integer_instance_id(kobj); > + > + if (instance_id < 0) > + return instance_id; Some attributes return -EIO here, some instance_id. This should be consistent. > + > + return sysfs_emit(buf, "%d\n", > + bioscfg_drv.integer_data[instance_id].current_value); > +} > + > +/* > + * validate_integer_input() - > + * Validate input of current_value against lower and upper bound > + * > + * @instance_id: The instance on which input is validated > + * @buf: Input value > + */ > +static int validate_integer_input(int instance_id, char *buf) > +{ > + int in_val; > + int ret; > + > + > + /* BIOS treats it as a read only attribute */ > + if (bioscfg_drv.integer_data[instance_id].common.is_readonly) > + return -EIO; > + > + ret = kstrtoint(buf, 10, &in_val); > + if (ret < 0) > + return ret; > + > + > + if (in_val < bioscfg_drv.integer_data[instance_id].lower_bound || > + in_val > bioscfg_drv.integer_data[instance_id].upper_bound) > + return -ERANGE; > + > + /* > + * set pending reboot flag depending on > + * "RequiresPhysicalPresence" value > + */ > + if (bioscfg_drv.integer_data[instance_id].common.requires_physical_presence) > + bioscfg_drv.pending_reboot = true; > + return 0; > +} > + > +static void update_integer_value(int instance_id, char *attr_value) > +{ > + int in_val; > + int ret; > + > + ret = kstrtoint(attr_value, 10, &in_val); > + if (ret == 0) > + bioscfg_drv.integer_data[instance_id].current_value = in_val; If the error is not propagated there should be at least be a warning. > +} > + > +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name_language_code, integer); > +static struct kobj_attribute integer_display_langcode = > + __ATTR_RO(display_name_language_code); > + > +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, integer); > +static struct kobj_attribute integer_display_name = > + __ATTR_RO(display_name); > + > +ATTRIBUTE_PROPERTY_STORE(current_value, integer); > +static struct kobj_attribute integer_current_val = > + __ATTR_RW_MODE(current_value, 0644); > + > +ATTRIBUTE_N_PROPERTY_SHOW(lower_bound, integer); > +static struct kobj_attribute integer_lower_bound = > + __ATTR_RO(lower_bound); > + > +ATTRIBUTE_N_PROPERTY_SHOW(upper_bound, integer); > +static struct kobj_attribute integer_upper_bound = > + __ATTR_RO(upper_bound); > + > +ATTRIBUTE_N_COMMON_PROPERTY_SHOW(prerequisites_size, integer); > +static struct kobj_attribute integer_prerequisites_size_val = > + __ATTR_RO(prerequisites_size); > + > +ATTRIBUTE_V_COMMON_PROPERTY_SHOW(prerequisites, integer); > +static struct kobj_attribute integer_prerequisites_val = > + __ATTR_RO(prerequisites); > + > +ATTRIBUTE_N_PROPERTY_SHOW(scalar_increment, integer); > +static struct kobj_attribute integer_scalar_increment = > + __ATTR_RO(scalar_increment); > + > +static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, > + char *buf) > +{ > + return sysfs_emit(buf, "integer\n"); > +} > +static struct kobj_attribute integer_type = > + __ATTR_RO(type); > + > +static struct attribute *integer_attrs[] = { > + &integer_display_langcode.attr, > + &integer_display_name.attr, > + &integer_current_val.attr, > + &integer_lower_bound.attr, > + &integer_upper_bound.attr, > + &integer_scalar_increment.attr, > + &integer_prerequisites_size_val.attr, > + &integer_prerequisites_val.attr, > + &integer_type.attr, > + NULL > +}; > + > +static const struct attribute_group integer_attr_group = { > + .attrs = integer_attrs, > +}; > + > +int alloc_integer_data(void) > +{ > + int ret = 0; No need for the ret variable. > + > + bioscfg_drv.integer_instances_count = get_instance_count(HP_WMI_BIOS_INTEGER_GUID); > + bioscfg_drv.integer_data = kcalloc(bioscfg_drv.integer_instances_count, > + sizeof(struct integer_data), GFP_KERNEL); sizeof(bioscfg_drv.integer_data); > + > + if (!bioscfg_drv.integer_data) { > + bioscfg_drv.integer_instances_count = 0; > + ret = -ENOMEM; > + } > + return ret; > +} > + > +/* Expected Values types associated with each element */ > +static const acpi_object_type expected_integer_types[] = { > + [NAME] = ACPI_TYPE_STRING, > + [VALUE] = ACPI_TYPE_STRING, > + [PATH] = ACPI_TYPE_STRING, > + [IS_READONLY] = ACPI_TYPE_INTEGER, > + [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER, > + [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER, > + [SEQUENCE] = ACPI_TYPE_INTEGER, > + [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER, > + [PREREQUISITES] = ACPI_TYPE_STRING, > + [SECURITY_LEVEL] = ACPI_TYPE_INTEGER, > + [INT_LOWER_BOUND] = ACPI_TYPE_INTEGER, > + [INT_UPPER_BOUND] = ACPI_TYPE_INTEGER, > + [INT_SCALAR_INCREMENT] = ACPI_TYPE_INTEGER Trailing comma. > +}; > + > +/* > + * populate_int_data() - > + * Populate all properties of an instance under integer attribute > + * > + * @integer_obj: ACPI object with integer data > + * @instance_id: The instance to enumerate > + * @attr_name_kobj: The parent kernel object > + */ > +int populate_integer_package_data(union acpi_object *integer_obj, > + int instance_id, > + struct kobject *attr_name_kobj) > +{ > + bioscfg_drv.integer_data[instance_id].attr_name_kobj = attr_name_kobj; > + populate_integer_elements_from_package(integer_obj, > + integer_obj->package.count, > + instance_id); > + update_attribute_permissions(bioscfg_drv.integer_data[instance_id].common.is_readonly, > + &integer_current_val); > + friendly_user_name_update(bioscfg_drv.integer_data[instance_id].common.path, > + attr_name_kobj->name, > + bioscfg_drv.integer_data[instance_id].common.display_name, > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name)); > + return sysfs_create_group(attr_name_kobj, &integer_attr_group); > +} > + > +int populate_integer_elements_from_package(union acpi_object *integer_obj, > + int integer_obj_count, > + int instance_id) > +{ > + char *str_value = NULL; > + int value_len; > + int ret = 0; > + u32 size = 0; > + u32 int_value; > + int elem = 0; > + int reqs; > + int eloc; > + > + if (!integer_obj) > + return -EINVAL; > + > + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, > + LANG_CODE_STR, > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); > + > + for (elem = 1, eloc = 1; elem < integer_obj_count; elem++, eloc++) { > + > + /* ONLY look at the first INTEGER_ELEM_CNT elements */ Why? > + if (eloc == INTEGER_ELEM_CNT) > + goto exit_integer_package; > + > + switch (integer_obj[elem].type) { > + case ACPI_TYPE_STRING: > + > + if (elem != PREREQUISITES) { > + ret = convert_hexstr_to_str(integer_obj[elem].string.pointer, > + integer_obj[elem].string.length, > + &str_value, &value_len); > + if (ret) > + continue; > + } > + break; > + case ACPI_TYPE_INTEGER: > + int_value = (u32)integer_obj[elem].integer.value; > + break; > + default: > + pr_warn("Unsupported object type [%d]\n", integer_obj[elem].type); > + continue; > + } > + /* Check that both expected and read object type match */ > + if (expected_integer_types[eloc] != integer_obj[elem].type) { > + pr_err("Error expected type %d for elem %d, but got type %d instead\n", > + expected_integer_types[eloc], elem, integer_obj[elem].type); > + return -EIO; > + } > + /* Assign appropriate element value to corresponding field*/ > + switch (eloc) { > + case VALUE: > + ret = kstrtoint(str_value, 10, &int_value); > + if (ret) > + continue; > + > + bioscfg_drv.integer_data[instance_id].current_value = int_value; > + break; > + case PATH: > + strscpy(bioscfg_drv.integer_data[instance_id].common.path, str_value, > + sizeof(bioscfg_drv.integer_data[instance_id].common.path)); > + break; > + case IS_READONLY: > + bioscfg_drv.integer_data[instance_id].common.is_readonly = int_value; > + break; > + case DISPLAY_IN_UI: > + bioscfg_drv.integer_data[instance_id].common.display_in_ui = int_value; > + break; > + case REQUIRES_PHYSICAL_PRESENCE: > + bioscfg_drv.integer_data[instance_id].common.requires_physical_presence = int_value; > + break; > + case SEQUENCE: > + bioscfg_drv.integer_data[instance_id].common.sequence = int_value; > + break; > + case PREREQUISITES_SIZE: > + bioscfg_drv.integer_data[instance_id].common.prerequisites_size = int_value; > + > + if (int_value > MAX_PREREQUISITES_SIZE) > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > + /* > + * This HACK is needed to keep the expected > + * element list pointing to the right obj[elem].type > + * when the size is zero. PREREQUISITES > + * object is omitted by BIOS when the size is > + * zero. > + */ > + if (int_value == 0) > + eloc++; > + break; > + case PREREQUISITES: > + size = bioscfg_drv.integer_data[instance_id].common.prerequisites_size; > + > + for (reqs = 0; reqs < size && reqs < MAX_PREREQUISITES_SIZE; reqs++) { > + if (elem >= integer_obj_count) { > + pr_err("Error elem-objects package is too small\n"); > + return -EINVAL; > + } > + > + ret = convert_hexstr_to_str(integer_obj[elem + reqs].string.pointer, > + integer_obj[elem + reqs].string.length, > + &str_value, &value_len); > + > + if (ret) > + continue; > + > + strscpy(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs], > + str_value, > + sizeof(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs])); > + kfree(str_value); > + } > + break; > + > + case SECURITY_LEVEL: > + bioscfg_drv.integer_data[instance_id].common.security_level = int_value; > + break; > + case INT_LOWER_BOUND: > + bioscfg_drv.integer_data[instance_id].lower_bound = int_value; > + break; > + case INT_UPPER_BOUND: > + bioscfg_drv.integer_data[instance_id].upper_bound = int_value; > + break; > + case INT_SCALAR_INCREMENT: > + bioscfg_drv.integer_data[instance_id].scalar_increment = int_value; > + break; > + default: > + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); > + break; > + } > + } > +exit_integer_package: > + kfree(str_value); > + return 0; > +} > + > + > +/* > + * populate_integer_buffer_data() - > + * Populate all properties of an instance under integer attribute > + * > + * @buffer_ptr: Buffer pointer > + * @buffer_size: Buffer size > + * @instance_id: The instance to enumerate > + * @attr_name_kobj: The parent kernel object > + */ > +int populate_integer_buffer_data(u8 *buffer_ptr, u32 *buffer_size, int instance_id, > + struct kobject *attr_name_kobj) > +{ > + bioscfg_drv.integer_data[instance_id].attr_name_kobj = attr_name_kobj; > + > + /* Populate integer elements */ > + populate_integer_elements_from_buffer(buffer_ptr, buffer_size, > + instance_id); > + update_attribute_permissions(bioscfg_drv.integer_data[instance_id].common.is_readonly, > + &integer_current_val); > + friendly_user_name_update(bioscfg_drv.integer_data[instance_id].common.path, > + attr_name_kobj->name, > + bioscfg_drv.integer_data[instance_id].common.display_name, > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name)); > + > + return sysfs_create_group(attr_name_kobj, &integer_attr_group); > +} > + > +int populate_integer_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > + int instance_id) > +{ > + char *dst = NULL; > + int elem; > + int reqs; > + int integer; > + int size = 0; > + int ret; > + int dst_size = *buffer_size / sizeof(u16); > + > + dst = kcalloc(dst_size, sizeof(char), GFP_KERNEL); > + if (!dst) > + return -ENOMEM; > + > + elem = 0; > + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, > + LANG_CODE_STR, > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); > + > + for (elem = 1; elem < 3; elem++) { > + > + ret = get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size); > + if (ret < 0) > + continue; > + > + switch (elem) { > + case VALUE: > + ret = kstrtoint(dst, 10, &integer); > + if (ret) > + continue; > + > + bioscfg_drv.integer_data[instance_id].current_value = integer; > + break; > + case PATH: > + strscpy(bioscfg_drv.integer_data[instance_id].common.path, dst, > + sizeof(bioscfg_drv.integer_data[instance_id].common.path)); > + break; > + default: > + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); > + break; > + } > + } > + > + for (elem = 3; elem < INTEGER_ELEM_CNT; elem++) { This loop pattern seems weird to me. It is not obvious that the values are read in the order of the switch() branches from the buffer. Something more obvious would be: instance.common.is_readonly = read_int_from_buf(&buffer_ptr); instance.common.display_in_ui = read_int_from_buf(&buffer_ptr); instance.common.requires_physical_presence = read_int_from_buf(&buffer_ptr); This would make it clear that these are fields read in order from the buffer. Without having to also look at the numeric values of the defines. Furthermore it would make the code shorter and errorhandling would be clearer and the API similar to the netlink APIs. Or maybe with error reporting: ret = read_int_from_buf(&buffer_ptr, &instance.common.is_readonly); if (ret) ... ret = read_int_from_buf(&buffer_ptr, &instance.common.display_in_ui); if (ret) ... > + > + if (elem != PREREQUISITES) { > + ret = get_integer_from_buffer((int **)&buffer_ptr, buffer_size, (int *)&integer); > + if (ret < 0) > + continue; > + } > + > + switch (elem) { > + > + case IS_READONLY: > + bioscfg_drv.integer_data[instance_id].common.is_readonly = integer; > + break; > + case DISPLAY_IN_UI: > + bioscfg_drv.integer_data[instance_id].common.display_in_ui = integer; > + break; > + case REQUIRES_PHYSICAL_PRESENCE: > + bioscfg_drv.integer_data[instance_id].common.requires_physical_presence = integer; > + break; > + case SEQUENCE: > + bioscfg_drv.integer_data[instance_id].common.sequence = integer; > + break; > + case PREREQUISITES_SIZE: > + bioscfg_drv.integer_data[instance_id].common.prerequisites_size = integer; > + size = integer; > + if (size > MAX_PREREQUISITES_SIZE) > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > + > + // PREREQUISITES: > + elem++; > + for (reqs = 0; reqs < size && reqs < MAX_PREREQUISITES_SIZE; reqs++) { > + ret = get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size); > + if (ret < 0) > + continue; > + > + strscpy(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs], > + dst, > + sizeof(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs])); > + } > + break; > + > + case SECURITY_LEVEL: > + bioscfg_drv.integer_data[instance_id].common.security_level = integer; > + break; > + case INT_LOWER_BOUND: > + bioscfg_drv.integer_data[instance_id].lower_bound = integer; > + break; > + case INT_UPPER_BOUND: > + bioscfg_drv.integer_data[instance_id].upper_bound = integer; > + break; > + case INT_SCALAR_INCREMENT: > + bioscfg_drv.integer_data[instance_id].scalar_increment = integer; > + break; > + > + default: > + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); > + break; > + } > + } > + kfree(dst); > + > + return 0; > +} > + > +/* > + * exit_integer_attributes() - Clear all attribute data > + * > + * Clears all data allocated for this group of attributes > + */ > +void exit_integer_attributes(void) > +{ > + int instance_id; > + > + for (instance_id = 0; instance_id < bioscfg_drv.integer_instances_count; instance_id++) { > + > + struct kobject *attr_name_kobj = bioscfg_drv.integer_data[instance_id].attr_name_kobj; > + > + if (attr_name_kobj) > + sysfs_remove_group(attr_name_kobj, &integer_attr_group); > + } > + bioscfg_drv.integer_instances_count = 0; > + > + kfree(bioscfg_drv.integer_data); > + bioscfg_drv.integer_data = NULL; > +}
On Sat, Apr 22, 2023 at 5:43 PM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > Hi Jorge, > > one thing I noticed: > > When I recommended to cut down the driver to a minimal feature set I > meant the minimal feature set currently known to the kernel. > > This would *not* be sufficient for your HP-specific agent software. > Just the standard type attributes, ordered-list and authentication. > > But in the end it would most probably still be a faster path to a > solution that *does* include the full featureset of your requirements. > > > Also when fixing review comments please try to fix them everywhere where > applicable. Most comments affect many parts of the code. Agree! > > On 2023-04-20 11:54:44-0500, Jorge Lopez wrote: > > --- > > Based on the latest platform-drivers-x86.git/for-next > > --- > > .../x86/hp/hp-bioscfg/int-attributes.c | 474 ++++++++++++++++++ > > 1 file changed, 474 insertions(+) > > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > > > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > > new file mode 100644 > > index 000000000000..d8ee39dac3f9 > > --- /dev/null > > +++ b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > > @@ -0,0 +1,474 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Functions corresponding to integer type attributes under > > + * BIOS Enumeration GUID for use with hp-bioscfg driver. > > + * > > + * Copyright (c) 2022 Hewlett-Packard Inc. > > + */ > > + > > +#include "bioscfg.h" > > + > > +GET_INSTANCE_ID(integer); > > + > > +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) > > +{ > > + int instance_id = get_integer_instance_id(kobj); > > + > > + if (instance_id < 0) > > + return instance_id; > > Some attributes return -EIO here, some instance_id. This should be > consistent. Done! > > > + > > + return sysfs_emit(buf, "%d\n", > > + bioscfg_drv.integer_data[instance_id].current_value); > > +} > > + > > +/* > > + * validate_integer_input() - > > + * Validate input of current_value against lower and upper bound > > + * > > + * @instance_id: The instance on which input is validated > > + * @buf: Input value > > + */ > > +static int validate_integer_input(int instance_id, char *buf) > > +{ > > + int in_val; > > + int ret; > > + > > + > > + /* BIOS treats it as a read only attribute */ > > + if (bioscfg_drv.integer_data[instance_id].common.is_readonly) > > + return -EIO; > > + > > + ret = kstrtoint(buf, 10, &in_val); > > + if (ret < 0) > > + return ret; > > + > > + > > + if (in_val < bioscfg_drv.integer_data[instance_id].lower_bound || > > + in_val > bioscfg_drv.integer_data[instance_id].upper_bound) > > + return -ERANGE; > > + > > + /* > > + * set pending reboot flag depending on > > + * "RequiresPhysicalPresence" value > > + */ > > + if (bioscfg_drv.integer_data[instance_id].common.requires_physical_presence) > > + bioscfg_drv.pending_reboot = true; > > + return 0; > > +} > > + > > +static void update_integer_value(int instance_id, char *attr_value) > > +{ > > + int in_val; > > + int ret; > > + > > + ret = kstrtoint(attr_value, 10, &in_val); > > + if (ret == 0) > > + bioscfg_drv.integer_data[instance_id].current_value = in_val; > > If the error is not propagated there should be at least be a warning. Done! > > > +} > > + > > +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name_language_code, integer); > > +static struct kobj_attribute integer_display_langcode = > > + __ATTR_RO(display_name_language_code); > > + > > +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, integer); > > +static struct kobj_attribute integer_display_name = > > + __ATTR_RO(display_name); > > + > > +ATTRIBUTE_PROPERTY_STORE(current_value, integer); > > +static struct kobj_attribute integer_current_val = > > + __ATTR_RW_MODE(current_value, 0644); > > + > > +ATTRIBUTE_N_PROPERTY_SHOW(lower_bound, integer); > > +static struct kobj_attribute integer_lower_bound = > > + __ATTR_RO(lower_bound); > > + > > +ATTRIBUTE_N_PROPERTY_SHOW(upper_bound, integer); > > +static struct kobj_attribute integer_upper_bound = > > + __ATTR_RO(upper_bound); > > + > > +ATTRIBUTE_N_COMMON_PROPERTY_SHOW(prerequisites_size, integer); > > +static struct kobj_attribute integer_prerequisites_size_val = > > + __ATTR_RO(prerequisites_size); > > + > > +ATTRIBUTE_V_COMMON_PROPERTY_SHOW(prerequisites, integer); > > +static struct kobj_attribute integer_prerequisites_val = > > + __ATTR_RO(prerequisites); > > + > > +ATTRIBUTE_N_PROPERTY_SHOW(scalar_increment, integer); > > +static struct kobj_attribute integer_scalar_increment = > > + __ATTR_RO(scalar_increment); > > + > > +static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, > > + char *buf) > > +{ > > + return sysfs_emit(buf, "integer\n"); > > +} > > +static struct kobj_attribute integer_type = > > + __ATTR_RO(type); > > + > > +static struct attribute *integer_attrs[] = { > > + &integer_display_langcode.attr, > > + &integer_display_name.attr, > > + &integer_current_val.attr, > > + &integer_lower_bound.attr, > > + &integer_upper_bound.attr, > > + &integer_scalar_increment.attr, > > + &integer_prerequisites_size_val.attr, > > + &integer_prerequisites_val.attr, > > + &integer_type.attr, > > + NULL > > +}; > > + > > +static const struct attribute_group integer_attr_group = { > > + .attrs = integer_attrs, > > +}; > > + > > +int alloc_integer_data(void) > > +{ > > + int ret = 0; > > No need for the ret variable. Done! > > > + > > + bioscfg_drv.integer_instances_count = get_instance_count(HP_WMI_BIOS_INTEGER_GUID); > > + bioscfg_drv.integer_data = kcalloc(bioscfg_drv.integer_instances_count, > > + sizeof(struct integer_data), GFP_KERNEL); > > sizeof(bioscfg_drv.integer_data); Done! > > > + > > + if (!bioscfg_drv.integer_data) { > > + bioscfg_drv.integer_instances_count = 0; > > + ret = -ENOMEM; > > + } > > + return ret; > > +} > > + > > +/* Expected Values types associated with each element */ > > +static const acpi_object_type expected_integer_types[] = { > > + [NAME] = ACPI_TYPE_STRING, > > + [VALUE] = ACPI_TYPE_STRING, > > + [PATH] = ACPI_TYPE_STRING, > > + [IS_READONLY] = ACPI_TYPE_INTEGER, > > + [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER, > > + [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER, > > + [SEQUENCE] = ACPI_TYPE_INTEGER, > > + [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER, > > + [PREREQUISITES] = ACPI_TYPE_STRING, > > + [SECURITY_LEVEL] = ACPI_TYPE_INTEGER, > > + [INT_LOWER_BOUND] = ACPI_TYPE_INTEGER, > > + [INT_UPPER_BOUND] = ACPI_TYPE_INTEGER, > > + [INT_SCALAR_INCREMENT] = ACPI_TYPE_INTEGER > > Trailing comma. Done! > > > +}; > > + > > +/* > > + * populate_int_data() - > > + * Populate all properties of an instance under integer attribute > > + * > > + * @integer_obj: ACPI object with integer data > > + * @instance_id: The instance to enumerate > > + * @attr_name_kobj: The parent kernel object > > + */ > > +int populate_integer_package_data(union acpi_object *integer_obj, > > + int instance_id, > > + struct kobject *attr_name_kobj) > > +{ > > + bioscfg_drv.integer_data[instance_id].attr_name_kobj = attr_name_kobj; > > + populate_integer_elements_from_package(integer_obj, > > + integer_obj->package.count, > > + instance_id); > > + update_attribute_permissions(bioscfg_drv.integer_data[instance_id].common.is_readonly, > > + &integer_current_val); > > + friendly_user_name_update(bioscfg_drv.integer_data[instance_id].common.path, > > + attr_name_kobj->name, > > + bioscfg_drv.integer_data[instance_id].common.display_name, > > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name)); > > + return sysfs_create_group(attr_name_kobj, &integer_attr_group); > > +} > > + > > +int populate_integer_elements_from_package(union acpi_object *integer_obj, > > + int integer_obj_count, > > + int instance_id) > > +{ > > + char *str_value = NULL; > > + int value_len; > > + int ret = 0; > > + u32 size = 0; > > + u32 int_value; > > + int elem = 0; > > + int reqs; > > + int eloc; > > + > > + if (!integer_obj) > > + return -EINVAL; > > + > > + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, > > + LANG_CODE_STR, > > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); > > + > > + for (elem = 1, eloc = 1; elem < integer_obj_count; elem++, eloc++) { > > + > > + /* ONLY look at the first INTEGER_ELEM_CNT elements */ > > Why? The information provided in element 0 from the package is ignored as directed by the BIOS team. Similar action is taken when reading the information from ACPI Buffer (populate_integer_elements_from_buffer()) > > > + if (eloc == INTEGER_ELEM_CNT) > > + goto exit_integer_package; > > + > > + switch (integer_obj[elem].type) { > > + case ACPI_TYPE_STRING: > > + > > + if (elem != PREREQUISITES) { > > + ret = convert_hexstr_to_str(integer_obj[elem].string.pointer, > > + integer_obj[elem].string.length, > > + &str_value, &value_len); > > + if (ret) > > + continue; > > + } > > + break; > > + case ACPI_TYPE_INTEGER: > > + int_value = (u32)integer_obj[elem].integer.value; > > + break; > > + default: > > + pr_warn("Unsupported object type [%d]\n", integer_obj[elem].type); > > + continue; > > + } > > + /* Check that both expected and read object type match */ > > + if (expected_integer_types[eloc] != integer_obj[elem].type) { > > + pr_err("Error expected type %d for elem %d, but got type %d instead\n", > > + expected_integer_types[eloc], elem, integer_obj[elem].type); > > + return -EIO; > > + } > > + /* Assign appropriate element value to corresponding field*/ > > + switch (eloc) { > > + case VALUE: > > + ret = kstrtoint(str_value, 10, &int_value); > > + if (ret) > > + continue; > > + > > + bioscfg_drv.integer_data[instance_id].current_value = int_value; > > + break; > > + case PATH: > > + strscpy(bioscfg_drv.integer_data[instance_id].common.path, str_value, > > + sizeof(bioscfg_drv.integer_data[instance_id].common.path)); > > + break; > > + case IS_READONLY: > > + bioscfg_drv.integer_data[instance_id].common.is_readonly = int_value; > > + break; > > + case DISPLAY_IN_UI: > > + bioscfg_drv.integer_data[instance_id].common.display_in_ui = int_value; > > + break; > > + case REQUIRES_PHYSICAL_PRESENCE: > > + bioscfg_drv.integer_data[instance_id].common.requires_physical_presence = int_value; > > + break; > > + case SEQUENCE: > > + bioscfg_drv.integer_data[instance_id].common.sequence = int_value; > > + break; > > + case PREREQUISITES_SIZE: > > + bioscfg_drv.integer_data[instance_id].common.prerequisites_size = int_value; > > + > > + if (int_value > MAX_PREREQUISITES_SIZE) > > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > + /* > > + * This HACK is needed to keep the expected > > + * element list pointing to the right obj[elem].type > > + * when the size is zero. PREREQUISITES > > + * object is omitted by BIOS when the size is > > + * zero. > > + */ > > + if (int_value == 0) > > + eloc++; > > + break; > > + case PREREQUISITES: > > + size = bioscfg_drv.integer_data[instance_id].common.prerequisites_size; > > + > > + for (reqs = 0; reqs < size && reqs < MAX_PREREQUISITES_SIZE; reqs++) { > > + if (elem >= integer_obj_count) { > > + pr_err("Error elem-objects package is too small\n"); > > + return -EINVAL; > > + } > > + > > + ret = convert_hexstr_to_str(integer_obj[elem + reqs].string.pointer, > > + integer_obj[elem + reqs].string.length, > > + &str_value, &value_len); > > + > > + if (ret) > > + continue; > > + > > + strscpy(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs], > > + str_value, > > + sizeof(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs])); > > + kfree(str_value); > > + } > > + break; > > + > > + case SECURITY_LEVEL: > > + bioscfg_drv.integer_data[instance_id].common.security_level = int_value; > > + break; > > + case INT_LOWER_BOUND: > > + bioscfg_drv.integer_data[instance_id].lower_bound = int_value; > > + break; > > + case INT_UPPER_BOUND: > > + bioscfg_drv.integer_data[instance_id].upper_bound = int_value; > > + break; > > + case INT_SCALAR_INCREMENT: > > + bioscfg_drv.integer_data[instance_id].scalar_increment = int_value; > > + break; > > + default: > > + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); > > + break; > > + } > > + } > > +exit_integer_package: > > + kfree(str_value); > > + return 0; > > +} > > + > > + > > +/* > > + * populate_integer_buffer_data() - > > + * Populate all properties of an instance under integer attribute > > + * > > + * @buffer_ptr: Buffer pointer > > + * @buffer_size: Buffer size > > + * @instance_id: The instance to enumerate > > + * @attr_name_kobj: The parent kernel object > > + */ > > +int populate_integer_buffer_data(u8 *buffer_ptr, u32 *buffer_size, int instance_id, > > + struct kobject *attr_name_kobj) > > +{ > > + bioscfg_drv.integer_data[instance_id].attr_name_kobj = attr_name_kobj; > > + > > + /* Populate integer elements */ > > + populate_integer_elements_from_buffer(buffer_ptr, buffer_size, > > + instance_id); > > + update_attribute_permissions(bioscfg_drv.integer_data[instance_id].common.is_readonly, > > + &integer_current_val); > > + friendly_user_name_update(bioscfg_drv.integer_data[instance_id].common.path, > > + attr_name_kobj->name, > > + bioscfg_drv.integer_data[instance_id].common.display_name, > > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name)); > > + > > + return sysfs_create_group(attr_name_kobj, &integer_attr_group); > > +} > > + > > +int populate_integer_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > > + int instance_id) > > +{ > > + char *dst = NULL; > > + int elem; > > + int reqs; > > + int integer; > > + int size = 0; > > + int ret; > > + int dst_size = *buffer_size / sizeof(u16); > > + > > + dst = kcalloc(dst_size, sizeof(char), GFP_KERNEL); > > + if (!dst) > > + return -ENOMEM; > > + > > + elem = 0; > > + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, > > + LANG_CODE_STR, > > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); > > + > > + for (elem = 1; elem < 3; elem++) { > > + > > + ret = get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size); > > + if (ret < 0) > > + continue; > > + > > + switch (elem) { > > + case VALUE: > > + ret = kstrtoint(dst, 10, &integer); > > + if (ret) > > + continue; > > + > > + bioscfg_drv.integer_data[instance_id].current_value = integer; > > + break; > > + case PATH: > > + strscpy(bioscfg_drv.integer_data[instance_id].common.path, dst, > > + sizeof(bioscfg_drv.integer_data[instance_id].common.path)); > > + break; > > + default: > > + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); > > + break; > > + } > > + } > > + > > + for (elem = 3; elem < INTEGER_ELEM_CNT; elem++) { > > This loop pattern seems weird to me. > It is not obvious that the values are read in the order of the switch() > branches from the buffer. > The order in which the data is read from the buffer is set by BIOS. The switch statement was used to enforce the reading order of the elements and provide additional clarity > Something more obvious would be: > > instance.common.is_readonly = read_int_from_buf(&buffer_ptr); > instance.common.display_in_ui = read_int_from_buf(&buffer_ptr); > instance.common.requires_physical_presence = read_int_from_buf(&buffer_ptr); > > This would make it clear that these are fields read in order from the > buffer. Without having to also look at the numeric values of the > defines. > > Furthermore it would make the code shorter and errorhandling would be > clearer and the API similar to the netlink APIs. > > Or maybe with error reporting: > > ret = read_int_from_buf(&buffer_ptr, &instance.common.is_readonly); > if (ret) > ... Instance.common.is_readonly is only evaluated when the user attempt to update an attribute current value > ret = read_int_from_buf(&buffer_ptr, &instance.common.display_in_ui); > if (ret) > ... Instance.common.display_in_ui has no specific use at this time. The code was made shorter and easier to understand by replacing the long statements with struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id]; ... integer_data->common.is_readonly = integer; Same approach was taken for all attribute files. > > > + > > + if (elem != PREREQUISITES) { > > + ret = get_integer_from_buffer((int **)&buffer_ptr, buffer_size, (int *)&integer); > > + if (ret < 0) > > + continue; > > + } > > + > > + switch (elem) { > > + > > + case IS_READONLY: > > + bioscfg_drv.integer_data[instance_id].common.is_readonly = integer; > > + break; > > + case DISPLAY_IN_UI: > > + bioscfg_drv.integer_data[instance_id].common.display_in_ui = integer; > > + break; > > + case REQUIRES_PHYSICAL_PRESENCE: > > + bioscfg_drv.integer_data[instance_id].common.requires_physical_presence = integer; > > + break; > > + case SEQUENCE: > > + bioscfg_drv.integer_data[instance_id].common.sequence = integer; > > + break; > > + case PREREQUISITES_SIZE: > > + bioscfg_drv.integer_data[instance_id].common.prerequisites_size = integer; > > + size = integer; > > + if (size > MAX_PREREQUISITES_SIZE) > > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > + > > + // PREREQUISITES: > > + elem++; > > + for (reqs = 0; reqs < size && reqs < MAX_PREREQUISITES_SIZE; reqs++) { > > + ret = get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size); > > + if (ret < 0) > > + continue; > > + > > + strscpy(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs], > > + dst, > > + sizeof(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs])); > > + } > > + break; > > + > > + case SECURITY_LEVEL: > > + bioscfg_drv.integer_data[instance_id].common.security_level = integer; > > + break; > > + case INT_LOWER_BOUND: > > + bioscfg_drv.integer_data[instance_id].lower_bound = integer; > > + break; > > + case INT_UPPER_BOUND: > > + bioscfg_drv.integer_data[instance_id].upper_bound = integer; > > + break; > > + case INT_SCALAR_INCREMENT: > > + bioscfg_drv.integer_data[instance_id].scalar_increment = integer; > > + break; > > + > > + default: > > + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); > > + break; > > + } > > + } > > + kfree(dst); > > + > > + return 0; > > +} > > + > > +/* > > + * exit_integer_attributes() - Clear all attribute data > > + * > > + * Clears all data allocated for this group of attributes > > + */ > > +void exit_integer_attributes(void) > > +{ > > + int instance_id; > > + > > + for (instance_id = 0; instance_id < bioscfg_drv.integer_instances_count; instance_id++) { > > + > > + struct kobject *attr_name_kobj = bioscfg_drv.integer_data[instance_id].attr_name_kobj; > > + > > + if (attr_name_kobj) > > + sysfs_remove_group(attr_name_kobj, &integer_attr_group); > > + } > > + bioscfg_drv.integer_instances_count = 0; > > + > > + kfree(bioscfg_drv.integer_data); > > + bioscfg_drv.integer_data = NULL; > > +}
Hi Jorge, thanks for incorporating my feedback, I'm curious for the next revision! The review comments are very terse but that is only to bring across their points better. Your effort is appreciated. On 2023-05-02 15:56:22-0500, Jorge Lopez wrote: <snip> > > On 2023-04-20 11:54:44-0500, Jorge Lopez wrote: > > > --- > > > Based on the latest platform-drivers-x86.git/for-next > > > --- > > > .../x86/hp/hp-bioscfg/int-attributes.c | 474 ++++++++++++++++++ > > > 1 file changed, 474 insertions(+) > > > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > > > > > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > > > new file mode 100644 > > > index 000000000000..d8ee39dac3f9 > > > --- /dev/null > > > +++ b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c <snip> > > > +int populate_integer_elements_from_package(union acpi_object *integer_obj, > > > + int integer_obj_count, > > > + int instance_id) > > > +{ > > > + char *str_value = NULL; > > > + int value_len; > > > + int ret = 0; > > > + u32 size = 0; > > > + u32 int_value; > > > + int elem = 0; > > > + int reqs; > > > + int eloc; > > > + > > > + if (!integer_obj) > > > + return -EINVAL; > > > + > > > + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, > > > + LANG_CODE_STR, > > > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); > > > + > > > + for (elem = 1, eloc = 1; elem < integer_obj_count; elem++, eloc++) { > > > + > > > + /* ONLY look at the first INTEGER_ELEM_CNT elements */ > > > > Why? > The information provided in element 0 from the package is ignored as > directed by the BIOS team. > Similar action is taken when reading the information from ACPI Buffer > (populate_integer_elements_from_buffer()) This should be mentioned somewhere. But my question was more why to we only look at INTEGER_ELEM_CNT? It is clear to me now, but this is very convulted. See below. <snip> > > > > > + > > > +int populate_integer_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > > > + int instance_id) > > > +{ > > > + char *dst = NULL; > > > + int elem; > > > + int reqs; > > > + int integer; > > > + int size = 0; > > > + int ret; > > > + int dst_size = *buffer_size / sizeof(u16); > > > + > > > + dst = kcalloc(dst_size, sizeof(char), GFP_KERNEL); > > > + if (!dst) > > > + return -ENOMEM; > > > + > > > + elem = 0; > > > + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, > > > + LANG_CODE_STR, > > > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); > > > + > > > + for (elem = 1; elem < 3; elem++) { > > > + > > > + ret = get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size); > > > + if (ret < 0) > > > + continue; > > > + > > > + switch (elem) { > > > + case VALUE: > > > + ret = kstrtoint(dst, 10, &integer); > > > + if (ret) > > > + continue; > > > + > > > + bioscfg_drv.integer_data[instance_id].current_value = integer; > > > + break; > > > + case PATH: > > > + strscpy(bioscfg_drv.integer_data[instance_id].common.path, dst, > > > + sizeof(bioscfg_drv.integer_data[instance_id].common.path)); > > > + break; > > > + default: > > > + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); > > > + break; > > > + } > > > + } > > > + > > > + for (elem = 3; elem < INTEGER_ELEM_CNT; elem++) { > > > > This loop pattern seems weird to me. > > It is not obvious that the values are read in the order of the switch() > > branches from the buffer. > > > > The order in which the data is read from the buffer is set by BIOS. This I understand. > The switch statement was used to enforce the reading order of the > elements and provide additional clarity This is not clear from the code alone. One also needs to know the concrete values of the enums. > > Something more obvious would be: > > > > instance.common.is_readonly = read_int_from_buf(&buffer_ptr); > > instance.common.display_in_ui = read_int_from_buf(&buffer_ptr); > > instance.common.requires_physical_presence = read_int_from_buf(&buffer_ptr); The proposed pattern above, just regular function calls, are also executed in the correct order, the order in which they are written. For a reader it is clear that the order is important and part of the ABI of the BIOS. > > This would make it clear that these are fields read in order from the > > buffer. Without having to also look at the numeric values of the > > defines. > > > > Furthermore it would make the code shorter and errorhandling would be > > clearer and the API similar to the netlink APIs. > > > > Or maybe with error reporting: > > > > ret = read_int_from_buf(&buffer_ptr, &instance.common.is_readonly); > > if (ret) > > ... > > Instance.common.is_readonly is only evaluated when the user attempt to > update an attribute current value is_readonly was only an example on how to more nicely read the data from the buffer. It applies to all values of all attribute types. > > ret = read_int_from_buf(&buffer_ptr, &instance.common.display_in_ui); > > if (ret) > > ... > > Instance.common.display_in_ui has no specific use at this time. > > The code was made shorter and easier to understand by replacing the > long statements with > > struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id]; > ... > integer_data->common.is_readonly = integer; > > Same approach was taken for all attribute files. Thanks! Please do try to use the "plain functioncall" pattern as outlined above. I think it can make the code much shorter and idiomatic.
On Tue, May 2, 2023 at 4:30 PM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > Hi Jorge, > > thanks for incorporating my feedback, I'm curious for the next revision! > > The review comments are very terse but that is only to bring across > their points better. Your effort is appreciated. > > On 2023-05-02 15:56:22-0500, Jorge Lopez wrote: > > <snip> > > > > On 2023-04-20 11:54:44-0500, Jorge Lopez wrote: > > > > --- > > > > Based on the latest platform-drivers-x86.git/for-next > > > > --- > > > > .../x86/hp/hp-bioscfg/int-attributes.c | 474 ++++++++++++++++++ > > > > 1 file changed, 474 insertions(+) > > > > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > > > > > > > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > > > > new file mode 100644 > > > > index 000000000000..d8ee39dac3f9 > > > > --- /dev/null > > > > +++ b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c > > <snip> > > > > > +int populate_integer_elements_from_package(union acpi_object *integer_obj, > > > > + int integer_obj_count, > > > > + int instance_id) > > > > +{ > > > > + char *str_value = NULL; > > > > + int value_len; > > > > + int ret = 0; > > > > + u32 size = 0; > > > > + u32 int_value; > > > > + int elem = 0; > > > > + int reqs; > > > > + int eloc; > > > > + > > > > + if (!integer_obj) > > > > + return -EINVAL; > > > > + > > > > + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, > > > > + LANG_CODE_STR, > > > > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); > > > > + > > > > + for (elem = 1, eloc = 1; elem < integer_obj_count; elem++, eloc++) { > > > > + > > > > + /* ONLY look at the first INTEGER_ELEM_CNT elements */ > > > > > > Why? > > The information provided in element 0 from the package is ignored as > > directed by the BIOS team. > > Similar action is taken when reading the information from ACPI Buffer > > (populate_integer_elements_from_buffer()) > > This should be mentioned somewhere. > > But my question was more why to we only look at INTEGER_ELEM_CNT? > It is clear to me now, but this is very convulted. See below. I am adding the following information to each attribute file for clarification. "The total number of elements (INT_ELEM_CNT) read include only data relevant to this driver and its functionality. BIOS defines the order in which each element is read. Element 0 data is not relevant to this driver hence it is ignored. For clarity, The switch statement list all element names (DISPLAY_IN_UI) which defines the order in which is read and the name matches the variable where the data is stored". > > <snip> > > > > > > > > + > > > > +int populate_integer_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > > > > + int instance_id) > > > > +{ > > > > + char *dst = NULL; > > > > + int elem; > > > > + int reqs; > > > > + int integer; > > > > + int size = 0; > > > > + int ret; > > > > + int dst_size = *buffer_size / sizeof(u16); > > > > + > > > > + dst = kcalloc(dst_size, sizeof(char), GFP_KERNEL); > > > > + if (!dst) > > > > + return -ENOMEM; > > > > + > > > > + elem = 0; > > > > + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, > > > > + LANG_CODE_STR, > > > > + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); > > > > + > > > > + for (elem = 1; elem < 3; elem++) { > > > > + > > > > + ret = get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size); > > > > + if (ret < 0) > > > > + continue; > > > > + > > > > + switch (elem) { > > > > + case VALUE: > > > > + ret = kstrtoint(dst, 10, &integer); > > > > + if (ret) > > > > + continue; > > > > + > > > > + bioscfg_drv.integer_data[instance_id].current_value = integer; > > > > + break; > > > > + case PATH: > > > > + strscpy(bioscfg_drv.integer_data[instance_id].common.path, dst, > > > > + sizeof(bioscfg_drv.integer_data[instance_id].common.path)); > > > > + break; > > > > + default: > > > > + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); > > > > + break; > > > > + } > > > > + } > > > > + > > > > + for (elem = 3; elem < INTEGER_ELEM_CNT; elem++) { > > > > > > This loop pattern seems weird to me. > > > It is not obvious that the values are read in the order of the switch() > > > branches from the buffer. > > > > > > > The order in which the data is read from the buffer is set by BIOS. > > This I understand. > > > The switch statement was used to enforce the reading order of the > > elements and provide additional clarity > > This is not clear from the code alone. One also needs to know the > concrete values of the enums. > > > > Something more obvious would be: > > > > > > instance.common.is_readonly = read_int_from_buf(&buffer_ptr); > > > instance.common.display_in_ui = read_int_from_buf(&buffer_ptr); > > > instance.common.requires_physical_presence = read_int_from_buf(&buffer_ptr); > > The proposed pattern above, just regular function calls, are also > executed in the correct order, the order in which they are written. > The code will be easier to follow and will not require checking of the results because failing conditions are ignored. This will be a good option for functions such populate_integer_elements_from_buffer(). Buffer elements. Refactoring package function, populate_integer_elements_from_package(), will introduce additional complexity and obfuscation. > For a reader it is clear that the order is important and part of the > ABI of the BIOS. > > > > This would make it clear that these are fields read in order from the > > > buffer. Without having to also look at the numeric values of the > > > defines. > > > > > > Furthermore it would make the code shorter and errorhandling would be > > > clearer and the API similar to the netlink APIs. > > > > > > Or maybe with error reporting: > > > > > > ret = read_int_from_buf(&buffer_ptr, &instance.common.is_readonly); > > > if (ret) > > > ... > > > > Instance.common.is_readonly is only evaluated when the user attempt to > > update an attribute current value > > is_readonly was only an example on how to more nicely read the data from > the buffer. It applies to all values of all attribute types. > > > > ret = read_int_from_buf(&buffer_ptr, &instance.common.display_in_ui); > > > if (ret) > > > ... > > > > Instance.common.display_in_ui has no specific use at this time. > > > > The code was made shorter and easier to understand by replacing the > > long statements with > > > > struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id]; > > ... > > integer_data->common.is_readonly = integer; > > > > Same approach was taken for all attribute files. > > Thanks! > > Please do try to use the "plain functioncall" pattern as outlined above. > I think it can make the code much shorter and idiomatic. Understood!
diff --git a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c new file mode 100644 index 000000000000..d8ee39dac3f9 --- /dev/null +++ b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c @@ -0,0 +1,474 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Functions corresponding to integer type attributes under + * BIOS Enumeration GUID for use with hp-bioscfg driver. + * + * Copyright (c) 2022 Hewlett-Packard Inc. + */ + +#include "bioscfg.h" + +GET_INSTANCE_ID(integer); + +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + int instance_id = get_integer_instance_id(kobj); + + if (instance_id < 0) + return instance_id; + + return sysfs_emit(buf, "%d\n", + bioscfg_drv.integer_data[instance_id].current_value); +} + +/* + * validate_integer_input() - + * Validate input of current_value against lower and upper bound + * + * @instance_id: The instance on which input is validated + * @buf: Input value + */ +static int validate_integer_input(int instance_id, char *buf) +{ + int in_val; + int ret; + + + /* BIOS treats it as a read only attribute */ + if (bioscfg_drv.integer_data[instance_id].common.is_readonly) + return -EIO; + + ret = kstrtoint(buf, 10, &in_val); + if (ret < 0) + return ret; + + + if (in_val < bioscfg_drv.integer_data[instance_id].lower_bound || + in_val > bioscfg_drv.integer_data[instance_id].upper_bound) + return -ERANGE; + + /* + * set pending reboot flag depending on + * "RequiresPhysicalPresence" value + */ + if (bioscfg_drv.integer_data[instance_id].common.requires_physical_presence) + bioscfg_drv.pending_reboot = true; + return 0; +} + +static void update_integer_value(int instance_id, char *attr_value) +{ + int in_val; + int ret; + + ret = kstrtoint(attr_value, 10, &in_val); + if (ret == 0) + bioscfg_drv.integer_data[instance_id].current_value = in_val; +} + +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name_language_code, integer); +static struct kobj_attribute integer_display_langcode = + __ATTR_RO(display_name_language_code); + +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, integer); +static struct kobj_attribute integer_display_name = + __ATTR_RO(display_name); + +ATTRIBUTE_PROPERTY_STORE(current_value, integer); +static struct kobj_attribute integer_current_val = + __ATTR_RW_MODE(current_value, 0644); + +ATTRIBUTE_N_PROPERTY_SHOW(lower_bound, integer); +static struct kobj_attribute integer_lower_bound = + __ATTR_RO(lower_bound); + +ATTRIBUTE_N_PROPERTY_SHOW(upper_bound, integer); +static struct kobj_attribute integer_upper_bound = + __ATTR_RO(upper_bound); + +ATTRIBUTE_N_COMMON_PROPERTY_SHOW(prerequisites_size, integer); +static struct kobj_attribute integer_prerequisites_size_val = + __ATTR_RO(prerequisites_size); + +ATTRIBUTE_V_COMMON_PROPERTY_SHOW(prerequisites, integer); +static struct kobj_attribute integer_prerequisites_val = + __ATTR_RO(prerequisites); + +ATTRIBUTE_N_PROPERTY_SHOW(scalar_increment, integer); +static struct kobj_attribute integer_scalar_increment = + __ATTR_RO(scalar_increment); + +static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "integer\n"); +} +static struct kobj_attribute integer_type = + __ATTR_RO(type); + +static struct attribute *integer_attrs[] = { + &integer_display_langcode.attr, + &integer_display_name.attr, + &integer_current_val.attr, + &integer_lower_bound.attr, + &integer_upper_bound.attr, + &integer_scalar_increment.attr, + &integer_prerequisites_size_val.attr, + &integer_prerequisites_val.attr, + &integer_type.attr, + NULL +}; + +static const struct attribute_group integer_attr_group = { + .attrs = integer_attrs, +}; + +int alloc_integer_data(void) +{ + int ret = 0; + + bioscfg_drv.integer_instances_count = get_instance_count(HP_WMI_BIOS_INTEGER_GUID); + bioscfg_drv.integer_data = kcalloc(bioscfg_drv.integer_instances_count, + sizeof(struct integer_data), GFP_KERNEL); + + if (!bioscfg_drv.integer_data) { + bioscfg_drv.integer_instances_count = 0; + ret = -ENOMEM; + } + return ret; +} + +/* Expected Values types associated with each element */ +static const acpi_object_type expected_integer_types[] = { + [NAME] = ACPI_TYPE_STRING, + [VALUE] = ACPI_TYPE_STRING, + [PATH] = ACPI_TYPE_STRING, + [IS_READONLY] = ACPI_TYPE_INTEGER, + [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER, + [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER, + [SEQUENCE] = ACPI_TYPE_INTEGER, + [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER, + [PREREQUISITES] = ACPI_TYPE_STRING, + [SECURITY_LEVEL] = ACPI_TYPE_INTEGER, + [INT_LOWER_BOUND] = ACPI_TYPE_INTEGER, + [INT_UPPER_BOUND] = ACPI_TYPE_INTEGER, + [INT_SCALAR_INCREMENT] = ACPI_TYPE_INTEGER +}; + +/* + * populate_int_data() - + * Populate all properties of an instance under integer attribute + * + * @integer_obj: ACPI object with integer data + * @instance_id: The instance to enumerate + * @attr_name_kobj: The parent kernel object + */ +int populate_integer_package_data(union acpi_object *integer_obj, + int instance_id, + struct kobject *attr_name_kobj) +{ + bioscfg_drv.integer_data[instance_id].attr_name_kobj = attr_name_kobj; + populate_integer_elements_from_package(integer_obj, + integer_obj->package.count, + instance_id); + update_attribute_permissions(bioscfg_drv.integer_data[instance_id].common.is_readonly, + &integer_current_val); + friendly_user_name_update(bioscfg_drv.integer_data[instance_id].common.path, + attr_name_kobj->name, + bioscfg_drv.integer_data[instance_id].common.display_name, + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name)); + return sysfs_create_group(attr_name_kobj, &integer_attr_group); +} + +int populate_integer_elements_from_package(union acpi_object *integer_obj, + int integer_obj_count, + int instance_id) +{ + char *str_value = NULL; + int value_len; + int ret = 0; + u32 size = 0; + u32 int_value; + int elem = 0; + int reqs; + int eloc; + + if (!integer_obj) + return -EINVAL; + + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, + LANG_CODE_STR, + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); + + for (elem = 1, eloc = 1; elem < integer_obj_count; elem++, eloc++) { + + /* ONLY look at the first INTEGER_ELEM_CNT elements */ + if (eloc == INTEGER_ELEM_CNT) + goto exit_integer_package; + + switch (integer_obj[elem].type) { + case ACPI_TYPE_STRING: + + if (elem != PREREQUISITES) { + ret = convert_hexstr_to_str(integer_obj[elem].string.pointer, + integer_obj[elem].string.length, + &str_value, &value_len); + if (ret) + continue; + } + break; + case ACPI_TYPE_INTEGER: + int_value = (u32)integer_obj[elem].integer.value; + break; + default: + pr_warn("Unsupported object type [%d]\n", integer_obj[elem].type); + continue; + } + /* Check that both expected and read object type match */ + if (expected_integer_types[eloc] != integer_obj[elem].type) { + pr_err("Error expected type %d for elem %d, but got type %d instead\n", + expected_integer_types[eloc], elem, integer_obj[elem].type); + return -EIO; + } + /* Assign appropriate element value to corresponding field*/ + switch (eloc) { + case VALUE: + ret = kstrtoint(str_value, 10, &int_value); + if (ret) + continue; + + bioscfg_drv.integer_data[instance_id].current_value = int_value; + break; + case PATH: + strscpy(bioscfg_drv.integer_data[instance_id].common.path, str_value, + sizeof(bioscfg_drv.integer_data[instance_id].common.path)); + break; + case IS_READONLY: + bioscfg_drv.integer_data[instance_id].common.is_readonly = int_value; + break; + case DISPLAY_IN_UI: + bioscfg_drv.integer_data[instance_id].common.display_in_ui = int_value; + break; + case REQUIRES_PHYSICAL_PRESENCE: + bioscfg_drv.integer_data[instance_id].common.requires_physical_presence = int_value; + break; + case SEQUENCE: + bioscfg_drv.integer_data[instance_id].common.sequence = int_value; + break; + case PREREQUISITES_SIZE: + bioscfg_drv.integer_data[instance_id].common.prerequisites_size = int_value; + + if (int_value > MAX_PREREQUISITES_SIZE) + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); + /* + * This HACK is needed to keep the expected + * element list pointing to the right obj[elem].type + * when the size is zero. PREREQUISITES + * object is omitted by BIOS when the size is + * zero. + */ + if (int_value == 0) + eloc++; + break; + case PREREQUISITES: + size = bioscfg_drv.integer_data[instance_id].common.prerequisites_size; + + for (reqs = 0; reqs < size && reqs < MAX_PREREQUISITES_SIZE; reqs++) { + if (elem >= integer_obj_count) { + pr_err("Error elem-objects package is too small\n"); + return -EINVAL; + } + + ret = convert_hexstr_to_str(integer_obj[elem + reqs].string.pointer, + integer_obj[elem + reqs].string.length, + &str_value, &value_len); + + if (ret) + continue; + + strscpy(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs], + str_value, + sizeof(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs])); + kfree(str_value); + } + break; + + case SECURITY_LEVEL: + bioscfg_drv.integer_data[instance_id].common.security_level = int_value; + break; + case INT_LOWER_BOUND: + bioscfg_drv.integer_data[instance_id].lower_bound = int_value; + break; + case INT_UPPER_BOUND: + bioscfg_drv.integer_data[instance_id].upper_bound = int_value; + break; + case INT_SCALAR_INCREMENT: + bioscfg_drv.integer_data[instance_id].scalar_increment = int_value; + break; + default: + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); + break; + } + } +exit_integer_package: + kfree(str_value); + return 0; +} + + +/* + * populate_integer_buffer_data() - + * Populate all properties of an instance under integer attribute + * + * @buffer_ptr: Buffer pointer + * @buffer_size: Buffer size + * @instance_id: The instance to enumerate + * @attr_name_kobj: The parent kernel object + */ +int populate_integer_buffer_data(u8 *buffer_ptr, u32 *buffer_size, int instance_id, + struct kobject *attr_name_kobj) +{ + bioscfg_drv.integer_data[instance_id].attr_name_kobj = attr_name_kobj; + + /* Populate integer elements */ + populate_integer_elements_from_buffer(buffer_ptr, buffer_size, + instance_id); + update_attribute_permissions(bioscfg_drv.integer_data[instance_id].common.is_readonly, + &integer_current_val); + friendly_user_name_update(bioscfg_drv.integer_data[instance_id].common.path, + attr_name_kobj->name, + bioscfg_drv.integer_data[instance_id].common.display_name, + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name)); + + return sysfs_create_group(attr_name_kobj, &integer_attr_group); +} + +int populate_integer_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, + int instance_id) +{ + char *dst = NULL; + int elem; + int reqs; + int integer; + int size = 0; + int ret; + int dst_size = *buffer_size / sizeof(u16); + + dst = kcalloc(dst_size, sizeof(char), GFP_KERNEL); + if (!dst) + return -ENOMEM; + + elem = 0; + strscpy(bioscfg_drv.integer_data[instance_id].common.display_name_language_code, + LANG_CODE_STR, + sizeof(bioscfg_drv.integer_data[instance_id].common.display_name_language_code)); + + for (elem = 1; elem < 3; elem++) { + + ret = get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size); + if (ret < 0) + continue; + + switch (elem) { + case VALUE: + ret = kstrtoint(dst, 10, &integer); + if (ret) + continue; + + bioscfg_drv.integer_data[instance_id].current_value = integer; + break; + case PATH: + strscpy(bioscfg_drv.integer_data[instance_id].common.path, dst, + sizeof(bioscfg_drv.integer_data[instance_id].common.path)); + break; + default: + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); + break; + } + } + + for (elem = 3; elem < INTEGER_ELEM_CNT; elem++) { + + if (elem != PREREQUISITES) { + ret = get_integer_from_buffer((int **)&buffer_ptr, buffer_size, (int *)&integer); + if (ret < 0) + continue; + } + + switch (elem) { + + case IS_READONLY: + bioscfg_drv.integer_data[instance_id].common.is_readonly = integer; + break; + case DISPLAY_IN_UI: + bioscfg_drv.integer_data[instance_id].common.display_in_ui = integer; + break; + case REQUIRES_PHYSICAL_PRESENCE: + bioscfg_drv.integer_data[instance_id].common.requires_physical_presence = integer; + break; + case SEQUENCE: + bioscfg_drv.integer_data[instance_id].common.sequence = integer; + break; + case PREREQUISITES_SIZE: + bioscfg_drv.integer_data[instance_id].common.prerequisites_size = integer; + size = integer; + if (size > MAX_PREREQUISITES_SIZE) + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); + + // PREREQUISITES: + elem++; + for (reqs = 0; reqs < size && reqs < MAX_PREREQUISITES_SIZE; reqs++) { + ret = get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size); + if (ret < 0) + continue; + + strscpy(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs], + dst, + sizeof(bioscfg_drv.integer_data[instance_id].common.prerequisites[reqs])); + } + break; + + case SECURITY_LEVEL: + bioscfg_drv.integer_data[instance_id].common.security_level = integer; + break; + case INT_LOWER_BOUND: + bioscfg_drv.integer_data[instance_id].lower_bound = integer; + break; + case INT_UPPER_BOUND: + bioscfg_drv.integer_data[instance_id].upper_bound = integer; + break; + case INT_SCALAR_INCREMENT: + bioscfg_drv.integer_data[instance_id].scalar_increment = integer; + break; + + default: + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); + break; + } + } + kfree(dst); + + return 0; +} + +/* + * exit_integer_attributes() - Clear all attribute data + * + * Clears all data allocated for this group of attributes + */ +void exit_integer_attributes(void) +{ + int instance_id; + + for (instance_id = 0; instance_id < bioscfg_drv.integer_instances_count; instance_id++) { + + struct kobject *attr_name_kobj = bioscfg_drv.integer_data[instance_id].attr_name_kobj; + + if (attr_name_kobj) + sysfs_remove_group(attr_name_kobj, &integer_attr_group); + } + bioscfg_drv.integer_instances_count = 0; + + kfree(bioscfg_drv.integer_data); + bioscfg_drv.integer_data = NULL; +}
HP BIOS Configuration driver purpose is to provide a driver supporting the latest sysfs class firmware attributes framework allowing the user to change BIOS settings and security solutions on HP Inc.’s commercial notebooks. Many features of HP Commercial notebooks can be managed using Windows Management Instrumentation (WMI). WMI is an implementation of Web-Based Enterprise Management (WBEM) that provides a standards-based interface for changing and monitoring system settings. HP BIOSCFG driver provides a native Linux solution and the exposed features facilitates the migration to Linux environments. The Linux security features to be provided in hp-bioscfg driver enables managing the BIOS settings and security solutions via sysfs, a virtual filesystem that can be used by user-mode applications. The new documentation cover HP-specific firmware sysfs attributes such Secure Platform Management and Sure Start. Each section provides security feature description and identifies sysfs directories and files exposed by the driver. Many HP Commercial notebooks include a feature called Secure Platform Management (SPM), which replaces older password-based BIOS settings management with public key cryptography. PC secure product management begins when a target system is provisioned with cryptographic keys that are used to ensure the integrity of communications between system management utilities and the BIOS. HP Commercial notebooks have several BIOS settings that control its behaviour and capabilities, many of which are related to security. To prevent unauthorized changes to these settings, the system can be configured to use a cryptographic signature-based authorization string that the BIOS will use to verify authorization to modify the setting. Linux Security components are under development and not published yet. The only linux component is the driver (hp bioscfg) at this time. Other published security components are under Windows. Signed-off-by: Jorge Lopez <jorge.lopez2@hp.com> --- Based on the latest platform-drivers-x86.git/for-next --- .../x86/hp/hp-bioscfg/int-attributes.c | 474 ++++++++++++++++++ 1 file changed, 474 insertions(+) create mode 100644 drivers/platform/x86/hp/hp-bioscfg/int-attributes.c