diff options
Diffstat (limited to 'include/linux/sysfs.h')
| -rw-r--r-- | include/linux/sysfs.h | 230 |
1 files changed, 201 insertions, 29 deletions
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 2caa34c1ca1a..f418aae4f113 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -61,22 +61,37 @@ do { \ /** * struct attribute_group - data structure used to declare an attribute group. * @name: Optional: Attribute group name - * If specified, the attribute group will be created in - * a new subdirectory with this name. + * If specified, the attribute group will be created in a + * new subdirectory with this name. Additionally when a + * group is named, @is_visible and @is_bin_visible may + * return SYSFS_GROUP_INVISIBLE to control visibility of + * the directory itself. * @is_visible: Optional: Function to return permissions associated with an - * attribute of the group. Will be called repeatedly for each - * non-binary attribute in the group. Only read/write + * attribute of the group. Will be called repeatedly for + * each non-binary attribute in the group. Only read/write * permissions as well as SYSFS_PREALLOC are accepted. Must - * return 0 if an attribute is not visible. The returned value - * will replace static permissions defined in struct attribute. + * return 0 if an attribute is not visible. The returned + * value will replace static permissions defined in struct + * attribute. Use SYSFS_GROUP_VISIBLE() when assigning this + * callback to specify separate _group_visible() and + * _attr_visible() handlers. * @is_bin_visible: * Optional: Function to return permissions associated with a * binary attribute of the group. Will be called repeatedly * for each binary attribute in the group. Only read/write - * permissions as well as SYSFS_PREALLOC are accepted. Must - * return 0 if a binary attribute is not visible. The returned - * value will replace static permissions defined in - * struct bin_attribute. + * permissions as well as SYSFS_PREALLOC (and the + * visibility flags for named groups) are accepted. Must + * return 0 if a binary attribute is not visible. The + * returned value will replace static permissions defined + * in struct bin_attribute. If @is_visible is not set, Use + * SYSFS_GROUP_VISIBLE() when assigning this callback to + * specify separate _group_visible() and _attr_visible() + * handlers. + * @bin_size: + * Optional: Function to return the size of a binary attribute + * of the group. Will be called repeatedly for each binary + * attribute in the group. Overwrites the size field embedded + * inside the attribute itself. * @attrs: Pointer to NULL terminated list of attributes. * @bin_attrs: Pointer to NULL terminated list of binary attributes. * Either attrs or bin_attrs or both must be provided. @@ -86,18 +101,132 @@ struct attribute_group { umode_t (*is_visible)(struct kobject *, struct attribute *, int); umode_t (*is_bin_visible)(struct kobject *, - struct bin_attribute *, int); + const struct bin_attribute *, int); + size_t (*bin_size)(struct kobject *, + const struct bin_attribute *, + int); struct attribute **attrs; - struct bin_attribute **bin_attrs; + union { + const struct bin_attribute *const *bin_attrs; + const struct bin_attribute *const *bin_attrs_new; + }; }; +#define SYSFS_PREALLOC 010000 +#define SYSFS_GROUP_INVISIBLE 020000 + +/* + * DEFINE_SYSFS_GROUP_VISIBLE(name): + * A helper macro to pair with the assignment of ".is_visible = + * SYSFS_GROUP_VISIBLE(name)", that arranges for the directory + * associated with a named attribute_group to optionally be hidden. + * This allows for static declaration of attribute_groups, and the + * simplification of attribute visibility lifetime that implies, + * without polluting sysfs with empty attribute directories. + * Ex. + * + * static umode_t example_attr_visible(struct kobject *kobj, + * struct attribute *attr, int n) + * { + * if (example_attr_condition) + * return 0; + * else if (ro_attr_condition) + * return 0444; + * return a->mode; + * } + * + * static bool example_group_visible(struct kobject *kobj) + * { + * if (example_group_condition) + * return false; + * return true; + * } + * + * DEFINE_SYSFS_GROUP_VISIBLE(example); + * + * static struct attribute_group example_group = { + * .name = "example", + * .is_visible = SYSFS_GROUP_VISIBLE(example), + * .attrs = &example_attrs, + * }; + * + * Note that it expects <name>_attr_visible and <name>_group_visible to + * be defined. For cases where individual attributes do not need + * separate visibility consideration, only entire group visibility at + * once, see DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(). + */ +#define DEFINE_SYSFS_GROUP_VISIBLE(name) \ + static inline umode_t sysfs_group_visible_##name( \ + struct kobject *kobj, struct attribute *attr, int n) \ + { \ + if (n == 0 && !name##_group_visible(kobj)) \ + return SYSFS_GROUP_INVISIBLE; \ + return name##_attr_visible(kobj, attr, n); \ + } + +/* + * DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(name): + * A helper macro to pair with SYSFS_GROUP_VISIBLE() that like + * DEFINE_SYSFS_GROUP_VISIBLE() controls group visibility, but does + * not require the implementation of a per-attribute visibility + * callback. + * Ex. + * + * static bool example_group_visible(struct kobject *kobj) + * { + * if (example_group_condition) + * return false; + * return true; + * } + * + * DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(example); + * + * static struct attribute_group example_group = { + * .name = "example", + * .is_visible = SYSFS_GROUP_VISIBLE(example), + * .attrs = &example_attrs, + * }; + */ +#define DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(name) \ + static inline umode_t sysfs_group_visible_##name( \ + struct kobject *kobj, struct attribute *a, int n) \ + { \ + if (n == 0 && !name##_group_visible(kobj)) \ + return SYSFS_GROUP_INVISIBLE; \ + return a->mode; \ + } + +/* + * Same as DEFINE_SYSFS_GROUP_VISIBLE, but for groups with only binary + * attributes. If an attribute_group defines both text and binary + * attributes, the group visibility is determined by the function + * specified to is_visible() not is_bin_visible() + */ +#define DEFINE_SYSFS_BIN_GROUP_VISIBLE(name) \ + static inline umode_t sysfs_group_visible_##name( \ + struct kobject *kobj, const struct bin_attribute *attr, int n) \ + { \ + if (n == 0 && !name##_group_visible(kobj)) \ + return SYSFS_GROUP_INVISIBLE; \ + return name##_attr_visible(kobj, attr, n); \ + } + +#define DEFINE_SIMPLE_SYSFS_BIN_GROUP_VISIBLE(name) \ + static inline umode_t sysfs_group_visible_##name( \ + struct kobject *kobj, const struct bin_attribute *a, int n) \ + { \ + if (n == 0 && !name##_group_visible(kobj)) \ + return SYSFS_GROUP_INVISIBLE; \ + return a->mode; \ + } + +#define SYSFS_GROUP_VISIBLE(fn) sysfs_group_visible_##fn + /* * Use these macros to make defining attributes easier. * See include/linux/device.h for examples.. */ -#define SYSFS_PREALLOC 010000 - #define __ATTR(_name, _mode, _show, _store) { \ .attr = {.name = __stringify(_name), \ .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \ @@ -162,18 +291,32 @@ static const struct attribute_group _name##_group = { \ }; \ __ATTRIBUTE_GROUPS(_name) +#define BIN_ATTRIBUTE_GROUPS(_name) \ +static const struct attribute_group _name##_group = { \ + .bin_attrs_new = _name##_attrs, \ +}; \ +__ATTRIBUTE_GROUPS(_name) + struct file; struct vm_area_struct; +struct address_space; struct bin_attribute { struct attribute attr; size_t size; void *private; - ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *, + struct address_space *(*f_mapping)(void); + ssize_t (*read)(struct file *, struct kobject *, const struct bin_attribute *, char *, loff_t, size_t); - ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *, + ssize_t (*read_new)(struct file *, struct kobject *, const struct bin_attribute *, + char *, loff_t, size_t); + ssize_t (*write)(struct file *, struct kobject *, const struct bin_attribute *, char *, loff_t, size_t); - int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr, + ssize_t (*write_new)(struct file *, struct kobject *, + const struct bin_attribute *, char *, loff_t, size_t); + loff_t (*llseek)(struct file *, struct kobject *, const struct bin_attribute *, + loff_t, int); + int (*mmap)(struct file *, struct kobject *, const struct bin_attribute *attr, struct vm_area_struct *vma); }; @@ -192,22 +335,16 @@ struct bin_attribute { /* macros to create static binary attributes easier */ #define __BIN_ATTR(_name, _mode, _read, _write, _size) { \ .attr = { .name = __stringify(_name), .mode = _mode }, \ - .read = _read, \ - .write = _write, \ + .read = _read, \ + .write = _write, \ .size = _size, \ } -#define __BIN_ATTR_RO(_name, _size) { \ - .attr = { .name = __stringify(_name), .mode = 0444 }, \ - .read = _name##_read, \ - .size = _size, \ -} +#define __BIN_ATTR_RO(_name, _size) \ + __BIN_ATTR(_name, 0444, _name##_read, NULL, _size) -#define __BIN_ATTR_WO(_name, _size) { \ - .attr = { .name = __stringify(_name), .mode = 0200 }, \ - .write = _name##_write, \ - .size = _size, \ -} +#define __BIN_ATTR_WO(_name, _size) \ + __BIN_ATTR(_name, 0200, NULL, _name##_write, _size) #define __BIN_ATTR_RW(_name, _size) \ __BIN_ATTR(_name, 0644, _name##_read, _name##_write, _size) @@ -227,6 +364,28 @@ struct bin_attribute bin_attr_##_name = __BIN_ATTR_WO(_name, _size) #define BIN_ATTR_RW(_name, _size) \ struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size) + +#define __BIN_ATTR_ADMIN_RO(_name, _size) \ + __BIN_ATTR(_name, 0400, _name##_read, NULL, _size) + +#define __BIN_ATTR_ADMIN_RW(_name, _size) \ + __BIN_ATTR(_name, 0600, _name##_read, _name##_write, _size) + +#define BIN_ATTR_ADMIN_RO(_name, _size) \ +struct bin_attribute bin_attr_##_name = __BIN_ATTR_ADMIN_RO(_name, _size) + +#define BIN_ATTR_ADMIN_RW(_name, _size) \ +struct bin_attribute bin_attr_##_name = __BIN_ATTR_ADMIN_RW(_name, _size) + +#define __BIN_ATTR_SIMPLE_RO(_name, _mode) \ + __BIN_ATTR(_name, _mode, sysfs_bin_attr_simple_read, NULL, 0) + +#define BIN_ATTR_SIMPLE_RO(_name) \ +struct bin_attribute bin_attr_##_name = __BIN_ATTR_SIMPLE_RO(_name, 0444) + +#define BIN_ATTR_SIMPLE_ADMIN_RO(_name) \ +struct bin_attribute bin_attr_##_name = __BIN_ATTR_SIMPLE_RO(_name, 0400) + struct sysfs_ops { ssize_t (*show)(struct kobject *, struct attribute *, char *); ssize_t (*store)(struct kobject *, struct attribute *, const char *, size_t); @@ -334,6 +493,10 @@ int sysfs_emit(char *buf, const char *fmt, ...); __printf(3, 4) int sysfs_emit_at(char *buf, int at, const char *fmt, ...); +ssize_t sysfs_bin_attr_simple_read(struct file *file, struct kobject *kobj, + const struct bin_attribute *attr, char *buf, + loff_t off, size_t count); + #else /* CONFIG_SYSFS */ static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) @@ -591,6 +754,15 @@ static inline int sysfs_emit_at(char *buf, int at, const char *fmt, ...) { return 0; } + +static inline ssize_t sysfs_bin_attr_simple_read(struct file *file, + struct kobject *kobj, + const struct bin_attribute *attr, + char *buf, loff_t off, + size_t count) +{ + return 0; +} #endif /* CONFIG_SYSFS */ static inline int __must_check sysfs_create_file(struct kobject *kobj, |