@@ -290,6 +290,7 @@ config_item_type::
struct config_group *(*make_group)(struct config_group *group,
const char *name);
int (*commit_item)(struct config_item *item);
+ int (*uncommit_item)(struct config_item *item);
void (*disconnect_notify)(struct config_group *group,
struct config_item *item);
void (*drop_item)(struct config_group *group,
@@ -490,9 +491,6 @@ pass up an error.
Committable Items
=================
-Note:
- Committable items are currently unimplemented.
-
Some config_items cannot have a valid initial state. That is, no
default values can be specified for the item's attributes such that the
item can do its work. Userspace must configure one or more attributes,
@@ -532,4 +530,4 @@ method returns zero and the item is moved to the "live" directory.
As rmdir(2) does not work in the "live" directory, an item must be
shutdown, or "uncommitted". Again, this is done via rename(2), this
time from the "live" directory back to the "pending" one. The subsystem
-is notified by the ct_group_ops->uncommit_object() method.
+is notified by the ct_group_ops->uncommit_item() method.
@@ -56,6 +56,8 @@ struct configfs_dirent {
#define CONFIGFS_USET_DROPPING (1UL << 8)
#define CONFIGFS_USET_IN_MKDIR (1UL << 9)
#define CONFIGFS_USET_CREATING (1UL << 10)
+#define CONFIGFS_GROUP_PENDING (1UL << 11)
+#define CONFIGFS_GROUP_LIVE (1UL << 12)
#define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR | CONFIGFS_ITEM_BIN_ATTR)
extern struct mutex configfs_symlink_mutex;
@@ -656,6 +656,13 @@ static void detach_groups(struct config_group *group)
inode_unlock(d_inode(child));
+ /*
+ * Free memory allocated for the pending and live directories
+ * of committable groups.
+ */
+ if (sd->s_type & (CONFIGFS_GROUP_PENDING | CONFIGFS_GROUP_LIVE))
+ kfree(sd->s_element);
+
d_delete(child);
dput(child);
}
@@ -860,6 +867,134 @@ static void configfs_detach_item(struct config_item *item)
configfs_remove_dir(item);
}
+static bool is_committable_group(struct config_item *item)
+{
+ const struct config_item_type *type = item->ci_type;
+
+ if (type && type->ct_group_ops &&
+ type->ct_group_ops->commit_item &&
+ type->ct_group_ops->uncommit_item)
+ return true;
+
+ return false;
+}
+
+struct pending_group_data {
+ struct config_group group;
+ struct config_item_type type;
+ struct configfs_group_operations group_ops;
+};
+
+struct live_group_data {
+ struct config_group group;
+ struct config_item_type type;
+};
+
+static int create_pending_group(struct config_item *parent_item,
+ struct configfs_fragment *frag)
+{
+ const struct config_item_type *parent_type = parent_item->ci_type;
+ struct pending_group_data *pending;
+ struct configfs_dirent *sd;
+ int ret;
+
+ pending = kzalloc(sizeof(*pending), GFP_KERNEL);
+ if (!pending)
+ return -ENOMEM;
+
+ /*
+ * Let's inherit the group_ops from the parent except for item
+ * committing and uncommitting.
+ */
+ memcpy(&pending->group_ops, parent_type->ct_group_ops,
+ sizeof(struct configfs_group_operations));
+ pending->type.ct_group_ops = &pending->group_ops;
+ pending->type.ct_group_ops->commit_item = NULL;
+ pending->type.ct_group_ops->uncommit_item = NULL;
+
+ /* Let's directly reuse item_ops. */
+ pending->type.ct_item_ops = parent_type->ct_item_ops;
+ pending->type.ct_owner = parent_type->ct_owner;
+
+ config_group_init_type_name(&pending->group, "pending", &pending->type);
+
+ ret = create_default_group(to_config_group(parent_item),
+ &pending->group, frag);
+ if (ret) {
+ kfree(pending);
+ return ret;
+ }
+
+ link_group(to_config_group(parent_item), &pending->group);
+
+ sd = pending->group.cg_item.ci_dentry->d_fsdata;
+ /* Allow creating config_items in 'pending' group. */
+ sd->s_type |= (CONFIGFS_GROUP_PENDING | CONFIGFS_USET_DIR);
+
+ return 0;
+}
+
+static int create_live_group(struct config_item *parent_item,
+ struct configfs_fragment *frag)
+{
+ struct live_group_data *live;
+ struct configfs_dirent *sd;
+ int ret;
+
+ live = kzalloc(sizeof(*live), GFP_KERNEL);
+ if (!live)
+ return -ENOMEM;
+
+ live->type.ct_owner = parent_item->ci_type->ct_owner;
+
+ config_group_init_type_name(&live->group, "live", &live->type);
+
+ ret = create_default_group(to_config_group(parent_item),
+ &live->group, frag);
+ if (ret) {
+ kfree(live);
+ return ret;
+ }
+
+ link_group(to_config_group(parent_item), &live->group);
+
+ sd = live->group.cg_item.ci_dentry->d_fsdata;
+ sd->s_type |= CONFIGFS_GROUP_LIVE;
+ sd->s_type &= ~CONFIGFS_USET_DIR;
+
+ return 0;
+}
+
+static int create_committable_groups(struct config_item *parent_item,
+ struct configfs_fragment *frag)
+{
+ struct configfs_dirent *sd;
+ int ret;
+
+ ret = create_pending_group(parent_item, frag);
+ if (ret)
+ return ret;
+
+ ret = create_live_group(parent_item, frag);
+ if (ret) {
+ detach_groups(to_config_group(parent_item));
+ return ret;
+ }
+
+ /* Disallow creating items directly in the committable group. */
+ sd = parent_item->ci_dentry->d_fsdata;
+ sd->s_type &= ~CONFIGFS_USET_DIR;
+
+ return 0;
+}
+
+static void dentry_mark_dead(struct config_item *item, struct dentry *dentry)
+{
+ configfs_detach_item(item);
+ d_inode(dentry)->i_flags |= S_DEAD;
+ dont_mount(dentry);
+}
+
static int configfs_attach_group(struct config_item *parent_item,
struct config_item *item,
struct dentry *dentry,
@@ -885,11 +1020,15 @@ static int configfs_attach_group(struct config_item *parent_item,
inode_lock_nested(d_inode(dentry), I_MUTEX_CHILD);
configfs_adjust_dir_dirent_depth_before_populate(sd);
ret = populate_groups(to_config_group(item), frag);
- if (ret) {
- configfs_detach_item(item);
- d_inode(dentry)->i_flags |= S_DEAD;
- dont_mount(dentry);
+ if (ret)
+ dentry_mark_dead(item, dentry);
+
+ if (is_committable_group(item)) {
+ ret = create_committable_groups(item, frag);
+ if (ret)
+ dentry_mark_dead(item, dentry);
}
+
configfs_adjust_dir_dirent_depth_after_populate(sd);
inode_unlock(d_inode(dentry));
if (ret)
@@ -966,6 +1105,8 @@ static void configfs_dump_one(struct configfs_dirent *sd, int level)
type_print(CONFIGFS_USET_DIR);
type_print(CONFIGFS_USET_DEFAULT);
type_print(CONFIGFS_USET_DROPPING);
+ type_print(CONFIGFS_GROUP_PENDING);
+ type_print(CONFIGFS_GROUP_LIVE);
#undef type_print
}
@@ -1457,7 +1598,7 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry)
struct config_item *parent_item;
struct config_item *item;
struct configfs_subsystem *subsys;
- struct configfs_dirent *sd;
+ struct configfs_dirent *sd, *parent_sd;
struct configfs_fragment *frag;
struct module *subsys_owner = NULL, *dead_item_owner = NULL;
int ret;
@@ -1476,6 +1617,12 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry)
return -EINVAL;
}
+ parent_sd = dentry->d_parent->d_fsdata;
+ if (parent_sd->s_type & CONFIGFS_GROUP_LIVE) {
+ config_item_put(parent_item);
+ return -EPERM;
+ }
+
/* configfs_mkdir() shouldn't have allowed this */
BUG_ON(!subsys->su_group.cg_item.ci_type);
subsys_owner = subsys->su_group.cg_item.ci_type->ct_owner;
@@ -1562,9 +1709,97 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry)
return 0;
}
+static int configfs_rename(struct user_namespace *mnt_userns,
+ struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
+{
+ struct configfs_dirent *sd, *old_parent_sd, *new_parent_sd;
+ struct dentry *old_parent_dentry, *new_parent_dentry;
+ struct dentry *committable_group_dentry;
+ struct config_item *committable_group_item, *item, *new_parent_item;
+ struct configfs_subsystem *committable_group_subsys;
+ struct configfs_group_operations *committable_group_ops;
+ int ret = 0;
+
+ if (flags)
+ return -EINVAL;
+
+ old_parent_dentry = old_dentry->d_parent;
+ new_parent_dentry = new_dentry->d_parent;
+
+ sd = old_dentry->d_fsdata;
+ old_parent_sd = old_dentry->d_parent->d_fsdata;
+ new_parent_sd = new_dentry->d_parent->d_fsdata;
+
+ if (!old_parent_sd || !new_parent_sd)
+ return -EPERM;
+
+ /*
+ * Renaming must always be between a 'pending' and a 'live' group and
+ * both need to have the same parent. Changing the directory name is
+ * not allowed.
+ */
+ if (!((old_parent_sd->s_type & CONFIGFS_GROUP_PENDING) &&
+ (new_parent_sd->s_type & CONFIGFS_GROUP_LIVE)) &&
+ !((old_parent_sd->s_type & CONFIGFS_GROUP_LIVE) &&
+ (new_parent_sd->s_type & CONFIGFS_GROUP_PENDING)))
+ return -EPERM;
+
+ if (old_parent_dentry->d_parent != new_parent_dentry->d_parent)
+ return -EPERM;
+
+ if (strcmp(old_dentry->d_name.name, new_dentry->d_name.name))
+ return -EPERM;
+
+ committable_group_dentry = old_parent_dentry->d_parent;
+ /*
+ * Grab a reference to the committable group for the duration of
+ * this function.
+ */
+ committable_group_item =
+ configfs_get_config_item(committable_group_dentry);
+ committable_group_subsys =
+ to_config_group(committable_group_item)->cg_subsys;
+ committable_group_ops = committable_group_item->ci_type->ct_group_ops;
+
+ item = sd->s_element;
+ new_parent_item = new_parent_sd->s_element;
+
+ if (WARN_ON(!is_committable_group(committable_group_item))) {
+ /* This would be a result of a programming error in configfs. */
+ config_item_put(committable_group_item);
+ return -EPERM;
+ }
+
+ mutex_lock(&committable_group_subsys->su_mutex);
+
+ if ((old_parent_sd->s_type & CONFIGFS_GROUP_PENDING) &&
+ (new_parent_sd->s_type & CONFIGFS_GROUP_LIVE))
+ ret = committable_group_ops->commit_item(item);
+ else
+ ret = committable_group_ops->uncommit_item(item);
+ if (ret)
+ goto out;
+
+ spin_lock(&configfs_dirent_lock);
+ new_dentry->d_fsdata = sd;
+ list_move(&sd->s_sibling, &new_parent_sd->s_children);
+ item->ci_parent = new_parent_item;
+ d_move(old_dentry, new_dentry);
+ spin_unlock(&configfs_dirent_lock);
+
+out:
+ mutex_unlock(&committable_group_subsys->su_mutex);
+ config_item_put(committable_group_item);
+
+ return ret;
+}
+
const struct inode_operations configfs_dir_inode_operations = {
.mkdir = configfs_mkdir,
.rmdir = configfs_rmdir,
+ .rename = configfs_rename,
.symlink = configfs_symlink,
.unlink = configfs_unlink,
.lookup = configfs_lookup,
@@ -219,6 +219,7 @@ struct configfs_group_operations {
struct config_item *(*make_item)(struct config_group *group, const char *name);
struct config_group *(*make_group)(struct config_group *group, const char *name);
int (*commit_item)(struct config_item *item);
+ int (*uncommit_item)(struct config_item *item);
void (*disconnect_notify)(struct config_group *group, struct config_item *item);
void (*drop_item)(struct config_group *group, struct config_item *item);
};