sysfs, kernfs: introduce sysfs_root_sd

Currently, it's assumed that there's a single kernfs hierarchy in the
system anchored at sysfs_root which is defined as a global struct.  To
allow other users of kernfs, this will be made dynamic.  Introduce a
new global variable sysfs_root_sd which points to &sysfs_root and
convert all &sysfs_root users.

This patch doesn't introduce any behavior difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index e5c4e711805048dae0ede17e445d1dafbb83a4aa..2fea501889e756774da3ccd110088ff08c0d354e 100644 (file)
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -68,7 +68,7 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
        if (kobj->parent)
                parent_sd = kobj->parent->sd;
        else
-               parent_sd = &sysfs_root;
+               parent_sd = sysfs_root_sd;
 
        if (!parent_sd)
                return -ENOENT;
@@ -134,7 +134,7 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj,
 
        BUG_ON(!sd->s_parent);
        new_parent_sd = new_parent_kobj && new_parent_kobj->sd ?
-               new_parent_kobj->sd : &sysfs_root;
+               new_parent_kobj->sd : sysfs_root_sd;
 
        return kernfs_rename_ns(sd, new_parent_sd, sd->s_name, new_ns);
 }

diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
index 0c80f03790167c4513f9a43eee4b5e146cb8becd..7cbd1fce28262f8a3c42bb16450d6c33a47a5346 100644 (file)
--- a/fs/sysfs/mount.c
+++ b/fs/sysfs/mount.c
@@ -32,7 +32,7 @@ static const struct super_operations sysfs_ops = {
        .evict_inode    = sysfs_evict_inode,
 };
 
-struct sysfs_dirent sysfs_root = {
+static struct sysfs_dirent sysfs_root = {
        .s_name         = "",
        .s_count        = ATOMIC_INIT(1),
        .s_flags        = SYSFS_DIR,
@@ -40,6 +40,8 @@ struct sysfs_dirent sysfs_root = {
        .s_ino          = 1,
 };
 
+struct sysfs_dirent *sysfs_root_sd = &sysfs_root;
+
 static int sysfs_fill_super(struct super_block *sb)
 {
        struct inode *inode;
@@ -53,7 +55,7 @@ static int sysfs_fill_super(struct super_block *sb)
 
        /* get root inode, initialize and unlock it */
        mutex_lock(&sysfs_mutex);
-       inode = sysfs_get_inode(sb, &sysfs_root);
+       inode = sysfs_get_inode(sb, sysfs_root_sd);
        mutex_unlock(&sysfs_mutex);
        if (!inode) {
                pr_debug("sysfs: could not get root inode\n");
@@ -66,7 +68,7 @@ static int sysfs_fill_super(struct super_block *sb)
                pr_debug("%s: could not get root dentry!\n", __func__);
                return -ENOMEM;
        }
-       root->d_fsdata = &sysfs_root;
+       root->d_fsdata = sysfs_root_sd;
        sb->s_root = root;
        sb->s_d_op = &sysfs_dentry_ops;
        return 0;

diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index 6797c9c2e43af3064166385267e99e924934e26e..62f0e014ec4898f1085d716204ff121b9c6dbbc0 100644 (file)
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -70,7 +70,7 @@ static int sysfs_do_create_link(struct kobject *kobj, struct kobject *target,
        struct sysfs_dirent *parent_sd = NULL;
 
        if (!kobj)
-               parent_sd = &sysfs_root;
+               parent_sd = sysfs_root_sd;
        else
                parent_sd = kobj->sd;
 
@@ -144,7 +144,7 @@ void sysfs_remove_link(struct kobject *kobj, const char *name)
        struct sysfs_dirent *parent_sd = NULL;
 
        if (!kobj)
-               parent_sd = &sysfs_root;
+               parent_sd = sysfs_root_sd;
        else
                parent_sd = kobj->sd;
 
@@ -170,7 +170,7 @@ int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *targ,
        int result;
 
        if (!kobj)
-               parent_sd = &sysfs_root;
+               parent_sd = sysfs_root_sd;
        else
                parent_sd = kobj->sd;
 

diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index ce97907e2894d9b6d232fb05c006e5b0981f7a12..2b217cef90be1ec9fa24c9798740dcaef1683f14 100644 (file)
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -28,7 +28,7 @@ struct sysfs_super_info {
        const void              *ns;
 };
 #define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
-extern struct sysfs_dirent sysfs_root;
+extern struct sysfs_dirent *sysfs_root_sd;
 extern struct kmem_cache *sysfs_dir_cachep;
 
 /*