*/
static u16 have_fork_callback __read_mostly;
static u16 have_exit_callback __read_mostly;
-static u16 have_free_callback __read_mostly;
+static u16 have_release_callback __read_mostly;
static u16 have_canfork_callback __read_mostly;
/* cgroup namespace for init task */
*root_flags = 0;
- if (!data)
+ if (!data || *data == '\0')
return 0;
while ((token = strsep(&data, ",")) != NULL) {
struct cgroup_namespace *ns)
{
struct dentry *dentry;
- bool new_sb;
+ bool new_sb = false;
dentry = kernfs_mount(fs_type, flags, root->kf_root, magic, &new_sb);
*/
if (!IS_ERR(dentry) && ns != &init_cgroup_ns) {
struct dentry *nsdentry;
+ struct super_block *sb = dentry->d_sb;
struct cgroup *cgrp;
mutex_lock(&cgroup_mutex);
spin_unlock_irq(&css_set_lock);
mutex_unlock(&cgroup_mutex);
- nsdentry = kernfs_node_dentry(cgrp->kn, dentry->d_sb);
+ nsdentry = kernfs_node_dentry(cgrp->kn, sb);
dput(dentry);
+ if (IS_ERR(nsdentry))
+ deactivate_locked_super(sb);
dentry = nsdentry;
}
- if (IS_ERR(dentry) || !new_sb)
+ if (!new_sb)
cgroup_put(&root->cgrp);
return dentry;
}
/**
- * cgroup_save_control - save control masks of a subtree
+ * cgroup_save_control - save control masks and dom_cgrp of a subtree
* @cgrp: root of the target subtree
*
- * Save ->subtree_control and ->subtree_ss_mask to the respective old_
- * prefixed fields for @cgrp's subtree including @cgrp itself.
+ * Save ->subtree_control, ->subtree_ss_mask and ->dom_cgrp to the
+ * respective old_ prefixed fields for @cgrp's subtree including @cgrp
+ * itself.
*/
static void cgroup_save_control(struct cgroup *cgrp)
{
cgroup_for_each_live_descendant_pre(dsct, d_css, cgrp) {
dsct->old_subtree_control = dsct->subtree_control;
dsct->old_subtree_ss_mask = dsct->subtree_ss_mask;
+ dsct->old_dom_cgrp = dsct->dom_cgrp;
}
}
}
/**
- * cgroup_restore_control - restore control masks of a subtree
+ * cgroup_restore_control - restore control masks and dom_cgrp of a subtree
* @cgrp: root of the target subtree
*
- * Restore ->subtree_control and ->subtree_ss_mask from the respective old_
- * prefixed fields for @cgrp's subtree including @cgrp itself.
+ * Restore ->subtree_control, ->subtree_ss_mask and ->dom_cgrp from the
+ * respective old_ prefixed fields for @cgrp's subtree including @cgrp
+ * itself.
*/
static void cgroup_restore_control(struct cgroup *cgrp)
{
cgroup_for_each_live_descendant_post(dsct, d_css, cgrp) {
dsct->subtree_control = dsct->old_subtree_control;
dsct->subtree_ss_mask = dsct->old_subtree_ss_mask;
+ dsct->dom_cgrp = dsct->old_dom_cgrp;
}
}
{
struct cgroup *parent = cgroup_parent(cgrp);
struct cgroup *dom_cgrp = parent->dom_cgrp;
+ struct cgroup *dsct;
+ struct cgroup_subsys_state *d_css;
int ret;
lockdep_assert_held(&cgroup_mutex);
if (cgroup_is_threaded(cgrp))
return 0;
+ /*
+ * If @cgroup is populated or has domain controllers enabled, it
+ * can't be switched. While the below cgroup_can_be_thread_root()
+ * test can catch the same conditions, that's only when @parent is
+ * not mixable, so let's check it explicitly.
+ */
+ if (cgroup_is_populated(cgrp) ||
+ cgrp->subtree_control & ~cgrp_dfl_threaded_ss_mask)
+ return -EOPNOTSUPP;
+
/* we're joining the parent's domain, ensure its validity */
if (!cgroup_is_valid_domain(dom_cgrp) ||
!cgroup_can_be_thread_root(dom_cgrp))
*/
cgroup_save_control(cgrp);
- cgrp->dom_cgrp = dom_cgrp;
+ cgroup_for_each_live_descendant_pre(dsct, d_css, cgrp)
+ if (dsct == cgrp || cgroup_is_threaded(dsct))
+ dsct->dom_cgrp = dom_cgrp;
+
ret = cgroup_apply_control(cgrp);
if (!ret)
parent->nr_threaded_children++;
- else
- cgrp->dom_cgrp = cgrp;
cgroup_finalize_control(cgrp, ret);
return ret;
key = &cft->lockdep_key;
#endif
kn = __kernfs_create_file(cgrp->kn, cgroup_file_name(cgrp, cft, name),
- cgroup_file_mode(cft), 0, cft->kf_ops, cft,
+ cgroup_file_mode(cft),
+ GLOBAL_ROOT_UID, GLOBAL_ROOT_GID,
+ 0, cft->kf_ops, cft,
NULL, key);
if (IS_ERR(kn))
return PTR_ERR(kn);
lockdep_assert_held(&css_set_lock);
repeat:
- /*
- * Advance iterator to find next entry. cset->tasks is consumed
- * first and then ->mg_tasks. After ->mg_tasks, we move onto the
- * next cset.
- */
- next = it->task_pos->next;
+ if (it->task_pos) {
+ /*
+ * Advance iterator to find next entry. cset->tasks is
+ * consumed first and then ->mg_tasks. After ->mg_tasks,
+ * we move onto the next cset.
+ */
+ next = it->task_pos->next;
- if (next == it->tasks_head)
- next = it->mg_tasks_head->next;
+ if (next == it->tasks_head)
+ next = it->mg_tasks_head->next;
- if (next == it->mg_tasks_head)
+ if (next == it->mg_tasks_head)
+ css_task_iter_advance_css_set(it);
+ else
+ it->task_pos = next;
+ } else {
+ /* called from start, proceed to the first cset */
css_task_iter_advance_css_set(it);
- else
- it->task_pos = next;
+ }
/* if PROCS, skip over tasks which aren't group leaders */
if ((it->flags & CSS_TASK_ITER_PROCS) && it->task_pos &&
it->cset_head = it->cset_pos;
- css_task_iter_advance_css_set(it);
+ css_task_iter_advance(it);
spin_unlock_irq(&css_set_lock);
}
},
{
.name = "cgroup.threads",
+ .flags = CFTYPE_NS_DELEGATABLE,
.release = cgroup_procs_release,
.seq_start = cgroup_threads_start,
.seq_next = cgroup_procs_next,
have_fork_callback |= (bool)ss->fork << ss->id;
have_exit_callback |= (bool)ss->exit << ss->id;
- have_free_callback |= (bool)ss->free << ss->id;
+ have_release_callback |= (bool)ss->release << ss->id;
have_canfork_callback |= (bool)ss->can_fork << ss->id;
/* At system boot, before all subsystems have been
} while_each_subsys_mask();
}
-void cgroup_free(struct task_struct *task)
+void cgroup_release(struct task_struct *task)
{
- struct css_set *cset = task_css_set(task);
struct cgroup_subsys *ss;
int ssid;
- do_each_subsys_mask(ss, ssid, have_free_callback) {
- ss->free(task);
+ do_each_subsys_mask(ss, ssid, have_release_callback) {
+ ss->release(task);
} while_each_subsys_mask();
+}
+void cgroup_free(struct task_struct *task)
+{
+ struct css_set *cset = task_css_set(task);
put_css_set(cset);
}
projects / mirror_ubuntu-bionic-kernel.git / blobdiff