Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android

[firefly-linux-kernel-4.4.55.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index f48196a7414c0628504daa321f8d6a857eab37d7..03a1b3f754d6aa3fc3be4aa3226beda3973bc3f6 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -211,6 +211,7 @@ static unsigned long have_free_callback __read_mostly;
 /* Ditto for the can_fork callback. */
 static unsigned long have_canfork_callback __read_mostly;
 
+static struct file_system_type cgroup2_fs_type;
 static struct cftype cgroup_dfl_base_files[];
 static struct cftype cgroup_legacy_base_files[];
 
@@ -1650,10 +1651,6 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
                        all_ss = true;
                        continue;
                }
-               if (!strcmp(token, "__DEVEL__sane_behavior")) {
-                       opts->flags |= CGRP_ROOT_SANE_BEHAVIOR;
-                       continue;
-               }
                if (!strcmp(token, "noprefix")) {
                        opts->flags |= CGRP_ROOT_NOPREFIX;
                        continue;
@@ -1720,15 +1717,6 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
                        return -ENOENT;
        }
 
-       if (opts->flags & CGRP_ROOT_SANE_BEHAVIOR) {
-               pr_warn("sane_behavior: this is still under development and its behaviors will change, proceed at your own risk\n");
-               if (nr_opts != 1) {
-                       pr_err("sane_behavior: no other mount options allowed\n");
-                       return -EINVAL;
-               }
-               return 0;
-       }
-
        /*
         * If the 'all' option was specified select all the subsystems,
         * otherwise if 'none', 'name=' and a subsystem name options were
@@ -2007,6 +1995,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
                         int flags, const char *unused_dev_name,
                         void *data)
 {
+       bool is_v2 = fs_type == &cgroup2_fs_type;
        struct super_block *pinned_sb = NULL;
        struct cgroup_subsys *ss;
        struct cgroup_root *root;
@@ -2023,6 +2012,17 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
        if (!use_task_css_set_links)
                cgroup_enable_task_cg_lists();
 
+       if (is_v2) {
+               if (data) {
+                       pr_err("cgroup2: unknown option \"%s\"\n", (char *)data);
+                       return ERR_PTR(-EINVAL);
+               }
+               cgrp_dfl_root_visible = true;
+               root = &cgrp_dfl_root;
+               cgroup_get(&root->cgrp);
+               goto out_mount;
+       }
+
        mutex_lock(&cgroup_mutex);
 
        /* First find the desired set of subsystems */
@@ -2030,15 +2030,6 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
        if (ret)
                goto out_unlock;
 
-       /* look for a matching existing root */
-       if (opts.flags & CGRP_ROOT_SANE_BEHAVIOR) {
-               cgrp_dfl_root_visible = true;
-               root = &cgrp_dfl_root;
-               cgroup_get(&root->cgrp);
-               ret = 0;
-               goto out_unlock;
-       }
-
        /*
         * Destruction of cgroup root is asynchronous, so subsystems may
         * still be dying after the previous unmount.  Let's drain the
@@ -2149,9 +2140,10 @@ out_free:
 
        if (ret)
                return ERR_PTR(ret);
-
+out_mount:
        dentry = kernfs_mount(fs_type, flags, root->kf_root,
-                               CGROUP_SUPER_MAGIC, &new_sb);
+                             is_v2 ? CGROUP2_SUPER_MAGIC : CGROUP_SUPER_MAGIC,
+                             &new_sb);
        if (IS_ERR(dentry) || !new_sb)
                cgroup_put(&root->cgrp);
 
@@ -2194,6 +2186,12 @@ static struct file_system_type cgroup_fs_type = {
        .kill_sb = cgroup_kill_sb,
 };
 
+static struct file_system_type cgroup2_fs_type = {
+       .name = "cgroup2",
+       .mount = cgroup_mount,
+       .kill_sb = cgroup_kill_sb,
+};
+
 /**
  * task_cgroup_path - cgroup path of a task in the first cgroup hierarchy
  * @task: target task
@@ -5390,6 +5388,7 @@ int __init cgroup_init(void)
 
        WARN_ON(sysfs_create_mount_point(fs_kobj, "cgroup"));
        WARN_ON(register_filesystem(&cgroup_fs_type));
+       WARN_ON(register_filesystem(&cgroup2_fs_type));
        WARN_ON(!proc_create("cgroups", 0, NULL, &proc_cgroupstats_operations));
 
        return 0;