diff options
Diffstat (limited to 'Documentation/filesystems/sysfs.txt')
| -rw-r--r-- | Documentation/filesystems/sysfs.txt | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/Documentation/filesystems/sysfs.txt b/Documentation/filesystems/sysfs.txt index dc276598a65..c8bce82ddca 100644 --- a/Documentation/filesystems/sysfs.txt +++ b/Documentation/filesystems/sysfs.txt @@ -90,7 +90,7 @@ void device_remove_file(struct device *, struct device_attribute *); It also defines this helper for defining device attributes: -#define DEVICE_ATTR(_name,_mode,_show,_store) \ +#define DEVICE_ATTR(_name, _mode, _show, _store) \ struct device_attribute dev_attr_##_name = { \ .attr = {.name = __stringify(_name) , .mode = _mode }, \ .show = _show, \ @@ -99,14 +99,14 @@ struct device_attribute dev_attr_##_name = { \ For example, declaring -static DEVICE_ATTR(foo,0644,show_foo,store_foo); +static DEVICE_ATTR(foo, S_IWUSR | S_IRUGO, show_foo, store_foo); is equivalent to doing: static struct device_attribute dev_attr_foo = { .attr = { .name = "foo", - .mode = 0644, + .mode = S_IWUSR | S_IRUGO, }, .show = show_foo, .store = store_foo, @@ -121,8 +121,8 @@ set of sysfs operations for forwarding read and write calls to the show and store methods of the attribute owners. struct sysfs_ops { - ssize_t (*show)(struct kobject *, struct attribute *,char *); - ssize_t (*store)(struct kobject *,struct attribute *,const char *); + ssize_t (*show)(struct kobject *, struct attribute *, char *); + ssize_t (*store)(struct kobject *, struct attribute *, const char *); }; [ Subsystems should have already defined a struct kobj_type as a @@ -137,7 +137,7 @@ calls the associated methods. To illustrate: -#define to_dev_attr(_attr) container_of(_attr,struct device_attribute,attr) +#define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr) #define to_dev(d) container_of(d, struct device, kobj) static ssize_t @@ -148,7 +148,7 @@ dev_attr_show(struct kobject * kobj, struct attribute * attr, char * buf) ssize_t ret = 0; if (dev_attr->show) - ret = dev_attr->show(dev,buf); + ret = dev_attr->show(dev, buf); return ret; } @@ -216,16 +216,16 @@ A very simple (and naive) implementation of a device attribute is: static ssize_t show_name(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf,"%s\n",dev->name); + return snprintf(buf, PAGE_SIZE, "%s\n", dev->name); } static ssize_t store_name(struct device * dev, const char * buf) { - sscanf(buf,"%20s",dev->name); - return strlen(buf); + sscanf(buf, "%20s", dev->name); + return strnlen(buf, PAGE_SIZE); } -static DEVICE_ATTR(name,S_IRUGO,show_name,store_name); +static DEVICE_ATTR(name, S_IRUGO, show_name, store_name); (Note that the real implementation doesn't allow userspace to set the @@ -290,7 +290,7 @@ struct device_attribute { Declaring: -DEVICE_ATTR(_name,_str,_mode,_show,_store); +DEVICE_ATTR(_name, _str, _mode, _show, _store); Creation/Removal: @@ -310,7 +310,7 @@ struct bus_attribute { Declaring: -BUS_ATTR(_name,_mode,_show,_store) +BUS_ATTR(_name, _mode, _show, _store) Creation/Removal: @@ -331,7 +331,7 @@ struct driver_attribute { Declaring: -DRIVER_ATTR(_name,_mode,_show,_store) +DRIVER_ATTR(_name, _mode, _show, _store) Creation/Removal: |