Messages in this thread | | | Date | Sat, 2 May 2020 02:32:12 +0200 | From | Sebastian Reichel <> | Subject | Re: [PATCH 1/4] power_supply: Cleanup power supply sysfs attribute list |
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Hi,
On Fri, Apr 24, 2020 at 11:35:30AM -0600, Mathew King wrote: > Make the device attribute list used to create sysfs attributes more > robust by decoupling the list order from order of the enum defined in > power_supply.h. This is done by using a designated initializer in the > POWER_SUPPLY_ATTR macro.
Thanks for doing this :)
> Also properties not added to the list will still be created with > name in the format "prop_*".
This is bad. We don't want to expose PROP_%d to userspace and risk this becoming ABI. Instead it should not be registered and a warning should be printed. This means we can drop the prop_name field and directly use upper, which will always be in TEXT segment then.
For the lower case name, I think it's better to provide it as second argument to POWER_SUPPLY_ATTR. Not very elegant solution, but it means, that the string is in the TEXT segment and that we can have the complete dev_attr initialized from the macro.
-- Sebastian
> Signed-off-by: Mathew King <mathewk@chromium.org> > --- > drivers/power/supply/power_supply.h | 7 +- > drivers/power/supply/power_supply_core.c | 9 +- > drivers/power/supply/power_supply_sysfs.c | 290 +++++++++++++--------- > 3 files changed, 179 insertions(+), 127 deletions(-) > > diff --git a/drivers/power/supply/power_supply.h b/drivers/power/supply/power_supply.h > index c310d4f36c10..e3475d35ec2a 100644 > --- a/drivers/power/supply/power_supply.h > +++ b/drivers/power/supply/power_supply.h > @@ -15,12 +15,15 @@ struct power_supply; > > #ifdef CONFIG_SYSFS > > -extern void power_supply_init_attrs(struct device_type *dev_type); > +extern int power_supply_init_attrs(struct device_type *dev_type); > +extern void power_supply_destroy_attrs(void); > extern int power_supply_uevent(struct device *dev, struct kobj_uevent_env *env); > > #else > > -static inline void power_supply_init_attrs(struct device_type *dev_type) {} > +static inline int power_supply_init_attrs(struct device_type *dev_type) > +{ return 0; } > +static void power_supply_destroy_attrs(void) {} > #define power_supply_uevent NULL > > #endif /* CONFIG_SYSFS */ > diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c > index 1a9a9fae73d3..7fb99302b532 100644 > --- a/drivers/power/supply/power_supply_core.c > +++ b/drivers/power/supply/power_supply_core.c > @@ -1329,19 +1329,26 @@ EXPORT_SYMBOL_GPL(power_supply_get_drvdata); > > static int __init power_supply_class_init(void) > { > + int ret; > power_supply_class = class_create(THIS_MODULE, "power_supply"); > > if (IS_ERR(power_supply_class)) > return PTR_ERR(power_supply_class); > > power_supply_class->dev_uevent = power_supply_uevent; > - power_supply_init_attrs(&power_supply_dev_type); > + > + ret = power_supply_init_attrs(&power_supply_dev_type); > + if (ret) { > + class_destroy(power_supply_class); > + return ret; > + } > > return 0; > } > > static void __exit power_supply_class_exit(void) > { > + power_supply_destroy_attrs(); > class_destroy(power_supply_class); > } > > diff --git a/drivers/power/supply/power_supply_sysfs.c b/drivers/power/supply/power_supply_sysfs.c > index f37ad4eae60b..b579081599d7 100644 > --- a/drivers/power/supply/power_supply_sysfs.c > +++ b/drivers/power/supply/power_supply_sysfs.c > @@ -18,27 +18,22 @@ > > #include "power_supply.h" > > -/* > - * This is because the name "current" breaks the device attr macro. > - * The "current" word resolves to "(get_current())" so instead of > - * "current" "(get_current())" appears in the sysfs. > - * > - * The source of this definition is the device.h which calls __ATTR > - * macro in sysfs.h which calls the __stringify macro. > - * > - * Only modification that the name is not tried to be resolved > - * (as a macro let's say). > - */ > +#define UNDEF_PROP_NAME_FMT "PROP_%d" > +#define UNDEF_PROP_NAME_LEN (strlen(UNDEF_PROP_NAME_FMT) + 2) > + > +struct power_supply_attr { > + const char *prop_name; > + const char *upper_name; > + const char *lower_name; > + struct device_attribute dev_attr; > +}; > > -#define POWER_SUPPLY_ATTR(_name) \ > -{ \ > - .attr = { .name = #_name }, \ > - .show = power_supply_show_property, \ > - .store = power_supply_store_property, \ > +#define POWER_SUPPLY_ATTR(_name) \ > +[POWER_SUPPLY_PROP_ ## _name] = \ > +{ \ > + .prop_name = #_name \ > } > > -static struct device_attribute power_supply_attrs[]; > - > static const char * const power_supply_type_text[] = { > "Unknown", "Battery", "UPS", "Mains", "USB", > "USB_DCP", "USB_CDP", "USB_ACA", "USB_C", > @@ -77,6 +72,91 @@ static const char * const power_supply_scope_text[] = { > "Unknown", "System", "Device" > }; > > +static struct power_supply_attr power_supply_attrs[] = { > + /* Properties of type `int' */ > + POWER_SUPPLY_ATTR(STATUS), > + POWER_SUPPLY_ATTR(CHARGE_TYPE), > + POWER_SUPPLY_ATTR(HEALTH), > + POWER_SUPPLY_ATTR(PRESENT), > + POWER_SUPPLY_ATTR(ONLINE), > + POWER_SUPPLY_ATTR(AUTHENTIC), > + POWER_SUPPLY_ATTR(TECHNOLOGY), > + POWER_SUPPLY_ATTR(CYCLE_COUNT), > + POWER_SUPPLY_ATTR(VOLTAGE_MAX), > + POWER_SUPPLY_ATTR(VOLTAGE_MIN), > + POWER_SUPPLY_ATTR(VOLTAGE_MAX_DESIGN), > + POWER_SUPPLY_ATTR(VOLTAGE_MIN_DESIGN), > + POWER_SUPPLY_ATTR(VOLTAGE_NOW), > + POWER_SUPPLY_ATTR(VOLTAGE_AVG), > + POWER_SUPPLY_ATTR(VOLTAGE_OCV), > + POWER_SUPPLY_ATTR(VOLTAGE_BOOT), > + POWER_SUPPLY_ATTR(CURRENT_MAX), > + POWER_SUPPLY_ATTR(CURRENT_NOW), > + POWER_SUPPLY_ATTR(CURRENT_AVG), > + POWER_SUPPLY_ATTR(CURRENT_BOOT), > + POWER_SUPPLY_ATTR(POWER_NOW), > + POWER_SUPPLY_ATTR(POWER_AVG), > + POWER_SUPPLY_ATTR(CHARGE_FULL_DESIGN), > + POWER_SUPPLY_ATTR(CHARGE_EMPTY_DESIGN), > + POWER_SUPPLY_ATTR(CHARGE_FULL), > + POWER_SUPPLY_ATTR(CHARGE_EMPTY), > + POWER_SUPPLY_ATTR(CHARGE_NOW), > + POWER_SUPPLY_ATTR(CHARGE_AVG), > + POWER_SUPPLY_ATTR(CHARGE_COUNTER), > + POWER_SUPPLY_ATTR(CONSTANT_CHARGE_CURRENT), > + POWER_SUPPLY_ATTR(CONSTANT_CHARGE_CURRENT_MAX), > + POWER_SUPPLY_ATTR(CONSTANT_CHARGE_VOLTAGE), > + POWER_SUPPLY_ATTR(CONSTANT_CHARGE_VOLTAGE_MAX), > + POWER_SUPPLY_ATTR(CHARGE_CONTROL_LIMIT), > + POWER_SUPPLY_ATTR(CHARGE_CONTROL_LIMIT_MAX), > + POWER_SUPPLY_ATTR(CHARGE_CONTROL_START_THRESHOLD), > + POWER_SUPPLY_ATTR(CHARGE_CONTROL_END_THRESHOLD), > + POWER_SUPPLY_ATTR(INPUT_CURRENT_LIMIT), > + POWER_SUPPLY_ATTR(INPUT_VOLTAGE_LIMIT), > + POWER_SUPPLY_ATTR(INPUT_POWER_LIMIT), > + POWER_SUPPLY_ATTR(ENERGY_FULL_DESIGN), > + POWER_SUPPLY_ATTR(ENERGY_EMPTY_DESIGN), > + POWER_SUPPLY_ATTR(ENERGY_FULL), > + POWER_SUPPLY_ATTR(ENERGY_EMPTY), > + POWER_SUPPLY_ATTR(ENERGY_NOW), > + POWER_SUPPLY_ATTR(ENERGY_AVG), > + POWER_SUPPLY_ATTR(CAPACITY), > + POWER_SUPPLY_ATTR(CAPACITY_ALERT_MIN), > + POWER_SUPPLY_ATTR(CAPACITY_ALERT_MAX), > + POWER_SUPPLY_ATTR(CAPACITY_LEVEL), > + POWER_SUPPLY_ATTR(TEMP), > + POWER_SUPPLY_ATTR(TEMP_MAX), > + POWER_SUPPLY_ATTR(TEMP_MIN), > + POWER_SUPPLY_ATTR(TEMP_ALERT_MIN), > + POWER_SUPPLY_ATTR(TEMP_ALERT_MAX), > + POWER_SUPPLY_ATTR(TEMP_AMBIENT), > + POWER_SUPPLY_ATTR(TEMP_AMBIENT_ALERT_MIN), > + POWER_SUPPLY_ATTR(TEMP_AMBIENT_ALERT_MAX), > + POWER_SUPPLY_ATTR(TIME_TO_EMPTY_NOW), > + POWER_SUPPLY_ATTR(TIME_TO_EMPTY_AVG), > + POWER_SUPPLY_ATTR(TIME_TO_FULL_NOW), > + POWER_SUPPLY_ATTR(TIME_TO_FULL_AVG), > + POWER_SUPPLY_ATTR(TYPE), > + POWER_SUPPLY_ATTR(USB_TYPE), > + POWER_SUPPLY_ATTR(SCOPE), > + POWER_SUPPLY_ATTR(PRECHARGE_CURRENT), > + POWER_SUPPLY_ATTR(CHARGE_TERM_CURRENT), > + POWER_SUPPLY_ATTR(CALIBRATE), > + /* Properties of type `const char *' */ > + POWER_SUPPLY_ATTR(MODEL_NAME), > + POWER_SUPPLY_ATTR(MANUFACTURER), > + POWER_SUPPLY_ATTR(SERIAL_NUMBER), > +}; > + > +static struct attribute * > +__power_supply_attrs[ARRAY_SIZE(power_supply_attrs) + 1]; > + > +static enum power_supply_property dev_attr_psp(struct device_attribute *attr) > +{ > + return container_of(attr, struct power_supply_attr, dev_attr) - > + power_supply_attrs; > +} > + > static ssize_t power_supply_show_usb_type(struct device *dev, > enum power_supply_usb_type *usb_types, > ssize_t num_usb_types, > @@ -117,7 +197,7 @@ static ssize_t power_supply_show_property(struct device *dev, > char *buf) { > ssize_t ret; > struct power_supply *psy = dev_get_drvdata(dev); > - enum power_supply_property psp = attr - power_supply_attrs; > + enum power_supply_property psp = dev_attr_psp(attr); > union power_supply_propval value; > > if (psp == POWER_SUPPLY_PROP_TYPE) { > @@ -186,7 +266,7 @@ static ssize_t power_supply_store_property(struct device *dev, > const char *buf, size_t count) { > ssize_t ret; > struct power_supply *psy = dev_get_drvdata(dev); > - enum power_supply_property psp = attr - power_supply_attrs; > + enum power_supply_property psp = dev_attr_psp(attr); > union power_supply_propval value; > > switch (psp) { > @@ -235,86 +315,6 @@ static ssize_t power_supply_store_property(struct device *dev, > return count; > } > > -/* Must be in the same order as POWER_SUPPLY_PROP_* */ > -static struct device_attribute power_supply_attrs[] = { > - /* Properties of type `int' */ > - POWER_SUPPLY_ATTR(status), > - POWER_SUPPLY_ATTR(charge_type), > - POWER_SUPPLY_ATTR(health), > - POWER_SUPPLY_ATTR(present), > - POWER_SUPPLY_ATTR(online), > - POWER_SUPPLY_ATTR(authentic), > - POWER_SUPPLY_ATTR(technology), > - POWER_SUPPLY_ATTR(cycle_count), > - POWER_SUPPLY_ATTR(voltage_max), > - POWER_SUPPLY_ATTR(voltage_min), > - POWER_SUPPLY_ATTR(voltage_max_design), > - POWER_SUPPLY_ATTR(voltage_min_design), > - POWER_SUPPLY_ATTR(voltage_now), > - POWER_SUPPLY_ATTR(voltage_avg), > - POWER_SUPPLY_ATTR(voltage_ocv), > - POWER_SUPPLY_ATTR(voltage_boot), > - POWER_SUPPLY_ATTR(current_max), > - POWER_SUPPLY_ATTR(current_now), > - POWER_SUPPLY_ATTR(current_avg), > - POWER_SUPPLY_ATTR(current_boot), > - POWER_SUPPLY_ATTR(power_now), > - POWER_SUPPLY_ATTR(power_avg), > - POWER_SUPPLY_ATTR(charge_full_design), > - POWER_SUPPLY_ATTR(charge_empty_design), > - POWER_SUPPLY_ATTR(charge_full), > - POWER_SUPPLY_ATTR(charge_empty), > - POWER_SUPPLY_ATTR(charge_now), > - POWER_SUPPLY_ATTR(charge_avg), > - POWER_SUPPLY_ATTR(charge_counter), > - POWER_SUPPLY_ATTR(constant_charge_current), > - POWER_SUPPLY_ATTR(constant_charge_current_max), > - POWER_SUPPLY_ATTR(constant_charge_voltage), > - POWER_SUPPLY_ATTR(constant_charge_voltage_max), > - POWER_SUPPLY_ATTR(charge_control_limit), > - POWER_SUPPLY_ATTR(charge_control_limit_max), > - POWER_SUPPLY_ATTR(charge_control_start_threshold), > - POWER_SUPPLY_ATTR(charge_control_end_threshold), > - POWER_SUPPLY_ATTR(input_current_limit), > - POWER_SUPPLY_ATTR(input_voltage_limit), > - POWER_SUPPLY_ATTR(input_power_limit), > - POWER_SUPPLY_ATTR(energy_full_design), > - POWER_SUPPLY_ATTR(energy_empty_design), > - POWER_SUPPLY_ATTR(energy_full), > - POWER_SUPPLY_ATTR(energy_empty), > - POWER_SUPPLY_ATTR(energy_now), > - POWER_SUPPLY_ATTR(energy_avg), > - POWER_SUPPLY_ATTR(capacity), > - POWER_SUPPLY_ATTR(capacity_alert_min), > - POWER_SUPPLY_ATTR(capacity_alert_max), > - POWER_SUPPLY_ATTR(capacity_level), > - POWER_SUPPLY_ATTR(temp), > - POWER_SUPPLY_ATTR(temp_max), > - POWER_SUPPLY_ATTR(temp_min), > - POWER_SUPPLY_ATTR(temp_alert_min), > - POWER_SUPPLY_ATTR(temp_alert_max), > - POWER_SUPPLY_ATTR(temp_ambient), > - POWER_SUPPLY_ATTR(temp_ambient_alert_min), > - POWER_SUPPLY_ATTR(temp_ambient_alert_max), > - POWER_SUPPLY_ATTR(time_to_empty_now), > - POWER_SUPPLY_ATTR(time_to_empty_avg), > - POWER_SUPPLY_ATTR(time_to_full_now), > - POWER_SUPPLY_ATTR(time_to_full_avg), > - POWER_SUPPLY_ATTR(type), > - POWER_SUPPLY_ATTR(usb_type), > - POWER_SUPPLY_ATTR(scope), > - POWER_SUPPLY_ATTR(precharge_current), > - POWER_SUPPLY_ATTR(charge_term_current), > - POWER_SUPPLY_ATTR(calibrate), > - /* Properties of type `const char *' */ > - POWER_SUPPLY_ATTR(model_name), > - POWER_SUPPLY_ATTR(manufacturer), > - POWER_SUPPLY_ATTR(serial_number), > -}; > - > -static struct attribute * > -__power_supply_attrs[ARRAY_SIZE(power_supply_attrs) + 1]; > - > static umode_t power_supply_attr_is_visible(struct kobject *kobj, > struct attribute *attr, > int attrno) > @@ -352,17 +352,7 @@ static const struct attribute_group *power_supply_attr_groups[] = { > NULL, > }; > > -void power_supply_init_attrs(struct device_type *dev_type) > -{ > - int i; > - > - dev_type->groups = power_supply_attr_groups; > - > - for (i = 0; i < ARRAY_SIZE(power_supply_attrs); i++) > - __power_supply_attrs[i] = &power_supply_attrs[i].attr; > -} > - > -static char *kstruprdup(const char *str, gfp_t gfp) > +static char *kstrlwrdup(const char *str, gfp_t gfp) > { > char *ret, *ustr; > > @@ -372,19 +362,75 @@ static char *kstruprdup(const char *str, gfp_t gfp) > return NULL; > > while (*str) > - *ustr++ = toupper(*str++); > + *ustr++ = tolower(*str++); > > *ustr = 0; > > return ret; > } > > +int power_supply_init_attrs(struct device_type *dev_type) > +{ > + int i; > + > + dev_type->groups = power_supply_attr_groups; > + > + for (i = 0; i < ARRAY_SIZE(power_supply_attrs); i++) { > + const char *upper, *lower; > + struct device_attribute *attr; > + > + upper = power_supply_attrs[i].prop_name; > + > + if (!upper) { > + char *name = kmalloc(UNDEF_PROP_NAME_LEN, GFP_KERNEL); > + > + if (!name) > + goto err_no_mem; > + > + sprintf(name, UNDEF_PROP_NAME_FMT, i); > + upper = name; > + } > + > + lower = kstrlwrdup(upper, GFP_KERNEL); > + > + if (!lower) > + goto err_no_mem; > + > + power_supply_attrs[i].upper_name = upper; > + power_supply_attrs[i].lower_name = lower; > + > + attr = &power_supply_attrs[i].dev_attr; > + > + attr->attr.name = lower; > + attr->show = power_supply_show_property; > + attr->store = power_supply_store_property; > + __power_supply_attrs[i] = &attr->attr; > + } > + > + return 0; > + > +err_no_mem: > + power_supply_destroy_attrs(); > + return -ENOMEM; > +} > + > +void power_supply_destroy_attrs(void) > +{ > + int i; > + > + for (i = 0; i < ARRAY_SIZE(power_supply_attrs); i++) { > + kfree(power_supply_attrs[i].lower_name); > + > + if (!power_supply_attrs[i].prop_name) > + kfree(power_supply_attrs[i].upper_name); > + } > +} > + > int power_supply_uevent(struct device *dev, struct kobj_uevent_env *env) > { > struct power_supply *psy = dev_get_drvdata(dev); > int ret = 0, j; > char *prop_buf; > - char *attrname; > > if (!psy || !psy->desc) { > dev_dbg(dev, "No power supply yet\n"); > @@ -400,12 +446,14 @@ int power_supply_uevent(struct device *dev, struct kobj_uevent_env *env) > return -ENOMEM; > > for (j = 0; j < psy->desc->num_properties; j++) { > - struct device_attribute *attr; > + struct power_supply_attr *pwr_attr; > + struct device_attribute *dev_attr; > char *line; > > - attr = &power_supply_attrs[psy->desc->properties[j]]; > + pwr_attr = &power_supply_attrs[psy->desc->properties[j]]; > + dev_attr = &pwr_attr->dev_attr; > > - ret = power_supply_show_property(dev, attr, prop_buf); > + ret = power_supply_show_property(dev, dev_attr, prop_buf); > if (ret == -ENODEV || ret == -ENODATA) { > /* When a battery is absent, we expect -ENODEV. Don't abort; > send the uevent with at least the the PRESENT=0 property */ > @@ -420,14 +468,8 @@ int power_supply_uevent(struct device *dev, struct kobj_uevent_env *env) > if (line) > *line = 0; > > - attrname = kstruprdup(attr->attr.name, GFP_KERNEL); > - if (!attrname) { > - ret = -ENOMEM; > - goto out; > - } > - > - ret = add_uevent_var(env, "POWER_SUPPLY_%s=%s", attrname, prop_buf); > - kfree(attrname); > + ret = add_uevent_var(env, "POWER_SUPPLY_%s=%s", > + pwr_attr->upper_name, prop_buf); > if (ret) > goto out; > } > -- > 2.26.2.303.gf8c07b1a785-goog > [unhandled content-type:application/pgp-signature] | |