ext4: create ext4_kset dynamically

ksets contain a kobject and they should always be allocated dynamically,
because it is unknown to whoever creates them when ksets can be
released.

Signed-off-by: Riccardo Schirone <sirmy15@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 192ade7d6fe6d82be5bdfc93c319d7c50062d8b1..1205261f130cbfa8ae82632399aa7beb73e4cc6a 100644 (file)
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -330,6 +330,13 @@ static void ext4_sb_release(struct kobject *kobj)
        complete(&sbi->s_kobj_unregister);
 }
 
+static void ext4_kset_release(struct kobject *kobj)
+{
+       struct kset *kset = container_of(kobj, struct kset, kobj);
+
+       kfree(kset);
+}
+
 static const struct sysfs_ops ext4_attr_ops = {
        .show   = ext4_attr_show,
        .store  = ext4_attr_store,
@@ -343,11 +350,10 @@ static struct kobj_type ext4_sb_ktype = {
 
 static struct kobj_type ext4_ktype = {
        .sysfs_ops      = &ext4_attr_ops,
+       .release        = ext4_kset_release,
 };
 
-static struct kset ext4_kset = {
-       .kobj   = {.ktype = &ext4_ktype},
-};
+static struct kset *ext4_kset;
 
 static struct kobj_type ext4_feat_ktype = {
        .default_attrs  = ext4_feat_attrs,
@@ -392,7 +398,7 @@ int ext4_register_sysfs(struct super_block *sb)
        const struct ext4_proc_files *p;
        int err;
 
-       sbi->s_kobj.kset = &ext4_kset;
+       sbi->s_kobj.kset = ext4_kset;
        init_completion(&sbi->s_kobj_unregister);
        err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, NULL,
                                   "%s", sb->s_id);
@@ -430,13 +436,16 @@ int __init ext4_init_sysfs(void)
 {
        int ret;
 
-       kobject_set_name(&ext4_kset.kobj, "ext4");
-       ext4_kset.kobj.parent = fs_kobj;
-       ret = kset_register(&ext4_kset);
-       if (ret) {
-               kset_unregister(&ext4_kset);
-               return ret;
-       }
+       ext4_kset = kzalloc(sizeof(*ext4_kset), GFP_KERNEL);
+       if (!ext4_kset)
+               return -ENOMEM;
+
+       kobject_set_name(&ext4_kset->kobj, "ext4");
+       ext4_kset->kobj.parent = fs_kobj;
+       ext4_kset->kobj.ktype = &ext4_ktype;
+       ret = kset_register(ext4_kset);
+       if (ret)
+               goto kset_err;
 
        ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL);
        if (!ext4_feat) {
@@ -444,7 +453,7 @@ int __init ext4_init_sysfs(void)
                goto kset_err;
        }
 
-       ext4_feat->kset = &ext4_kset;
+       ext4_feat->kset = ext4_kset;
        ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype,
                                   NULL, "features");
        if (ret)
@@ -456,14 +465,16 @@ int __init ext4_init_sysfs(void)
 feat_err:
        kobject_put(ext4_feat);
 kset_err:
-       kset_unregister(&ext4_kset);
+       kset_unregister(ext4_kset);
+       ext4_kset = NULL;
        return ret;
 }
 
 void ext4_exit_sysfs(void)
 {
        kobject_put(ext4_feat);
-       kset_unregister(&ext4_kset);
+       kset_unregister(ext4_kset);
+       ext4_kset = NULL;
        remove_proc_entry(proc_dirname, NULL);
        ext4_proc_root = NULL;
 }