mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-12 13:55:32 +00:00
ba631941ef
This patch adds the ability to change (set/clear) features while the file system is mounted. A bitmask is added for each feature set for the support to set and clear the bits. A message indicating which bit has been set or cleared is issued when it's been changed and also when permission or support for a particular bit has been denied. Since the the attributes can now be writable, we need to introduce another struct attribute to hold the different permissions. If neither set or clear is supported, the file will have 0444 permissions. If either set or clear is supported, the file will have 0644 permissions and the store handler will filter out the write based on the bitmask. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <clm@fb.com>
54 lines
1.8 KiB
C
54 lines
1.8 KiB
C
#ifndef _BTRFS_SYSFS_H_
|
|
#define _BTRFS_SYSFS_H_
|
|
|
|
enum btrfs_feature_set {
|
|
FEAT_COMPAT,
|
|
FEAT_COMPAT_RO,
|
|
FEAT_INCOMPAT,
|
|
FEAT_MAX
|
|
};
|
|
|
|
#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
|
|
{ \
|
|
.attr = { .name = __stringify(_name), .mode = _mode }, \
|
|
.show = _show, \
|
|
.store = _store, \
|
|
}
|
|
|
|
#define BTRFS_ATTR_RW(_name, _mode, _show, _store) \
|
|
static struct kobj_attribute btrfs_attr_##_name = \
|
|
__INIT_KOBJ_ATTR(_name, _mode, _show, _store)
|
|
#define BTRFS_ATTR(_name, _mode, _show) \
|
|
BTRFS_ATTR_RW(_name, _mode, _show, NULL)
|
|
#define BTRFS_ATTR_PTR(_name) (&btrfs_attr_##_name.attr)
|
|
|
|
struct btrfs_feature_attr {
|
|
struct kobj_attribute kobj_attr;
|
|
enum btrfs_feature_set feature_set;
|
|
u64 feature_bit;
|
|
};
|
|
|
|
#define BTRFS_FEAT_ATTR(_name, _feature_set, _prefix, _feature_bit) \
|
|
static struct btrfs_feature_attr btrfs_attr_##_name = { \
|
|
.kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
|
|
btrfs_feature_attr_show, \
|
|
btrfs_feature_attr_store), \
|
|
.feature_set = _feature_set, \
|
|
.feature_bit = _prefix ##_## _feature_bit, \
|
|
}
|
|
#define BTRFS_FEAT_ATTR_PTR(_name) (&btrfs_attr_##_name.kobj_attr.attr)
|
|
|
|
#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
|
|
BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
|
|
#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
|
|
BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT, feature)
|
|
#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
|
|
BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
|
|
|
|
/* convert from attribute */
|
|
#define to_btrfs_feature_attr(a) \
|
|
container_of(a, struct btrfs_feature_attr, kobj_attr)
|
|
#define attr_to_btrfs_attr(a) container_of(a, struct kobj_attribute, attr)
|
|
#define attr_to_btrfs_feature_attr(a) \
|
|
to_btrfs_feature_attr(attr_to_btrfs_attr(a))
|
|
#endif /* _BTRFS_SYSFS_H_ */
|