configfs: kill configfs_sb

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/configfs/configfs_internal.h

@@ -63,7 +63,7 @@ extern struct kmem_cache *configfs_dir_cachep;
 
 extern int configfs_is_root(struct config_item *item);
 
-extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent *);
+extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent *, struct super_block *);
 extern int configfs_create(struct dentry *, umode_t mode, int (*init)(struct inode *));
 extern int configfs_inode_init(void);
 extern void configfs_inode_exit(void);
@@ -84,7 +84,6 @@ extern int configfs_pin_fs(void);
 extern void configfs_release_fs(void);
 
 extern struct rw_semaphore configfs_rename_sem;
-extern struct super_block * configfs_sb;
 extern const struct file_operations configfs_dir_operations;
 extern const struct file_operations configfs_file_operations;
 extern const struct file_operations bin_fops;

fs/configfs/dir.c

@@ -1079,6 +1079,7 @@ int configfs_depend_item(struct configfs_subsystem *subsys,
 	int ret;
 	struct configfs_dirent *p, *root_sd, *subsys_sd = NULL;
 	struct config_item *s_item = &subsys->su_group.cg_item;
+	struct dentry *root;
 
 	/*
 	 * Pin the configfs filesystem.  This means we can safely access
@@ -1093,9 +1094,10 @@ int configfs_depend_item(struct configfs_subsystem *subsys,
 	 * subsystem is really registered, and so we need to lock out
 	 * configfs_[un]register_subsystem().
 	 */
-	mutex_lock(&configfs_sb->s_root->d_inode->i_mutex);
+	root = configfs_mount->mnt_root;
+	mutex_lock(&root->d_inode->i_mutex);
 
-	root_sd = configfs_sb->s_root->d_fsdata;
+	root_sd = root->d_fsdata;
 
 	list_for_each_entry(p, &root_sd->s_children, s_sibling) {
 		if (p->s_type & CONFIGFS_DIR) {
@@ -1129,7 +1131,7 @@ int configfs_depend_item(struct configfs_subsystem *subsys,
 out_unlock_dirent_lock:
 	spin_unlock(&configfs_dirent_lock);
 out_unlock_fs:
-	mutex_unlock(&configfs_sb->s_root->d_inode->i_mutex);
+	mutex_unlock(&root->d_inode->i_mutex);
 
 	/*
 	 * If we succeeded, the fs is pinned via other methods.  If not,
@@ -1543,6 +1545,7 @@ static inline unsigned char dt_type(struct configfs_dirent *sd)
 static int configfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
 {
 	struct dentry *dentry = filp->f_path.dentry;
+	struct super_block *sb = dentry->d_sb;
 	struct configfs_dirent * parent_sd = dentry->d_fsdata;
 	struct configfs_dirent *cursor = filp->private_data;
 	struct list_head *p, *q = &cursor->s_sibling;
@@ -1605,7 +1608,7 @@ static int configfs_readdir(struct file * filp, void * dirent, filldir_t filldir
 					ino = inode->i_ino;
 				spin_unlock(&configfs_dirent_lock);
 				if (!inode)
-					ino = iunique(configfs_sb, 2);
+					ino = iunique(sb, 2);
 
 				if (filldir(dirent, name, len, filp->f_pos, ino,
 						 dt_type(next)) < 0)
@@ -1677,6 +1680,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
 	struct config_group *group = &subsys->su_group;
 	struct qstr name;
 	struct dentry *dentry;
+	struct dentry *root;
 	struct configfs_dirent *sd;
 
 	err = configfs_pin_fs();
@@ -1686,18 +1690,18 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
 	if (!group->cg_item.ci_name)
 		group->cg_item.ci_name = group->cg_item.ci_namebuf;
 
-	sd = configfs_sb->s_root->d_fsdata;
+	root = configfs_mount->mnt_root;
+	sd = root->d_fsdata;
 	link_group(to_config_group(sd->s_element), group);
 
-	mutex_lock_nested(&configfs_sb->s_root->d_inode->i_mutex,
-			I_MUTEX_PARENT);
+	mutex_lock_nested(&root->d_inode->i_mutex, I_MUTEX_PARENT);
 
 	name.name = group->cg_item.ci_name;
 	name.len = strlen(name.name);
 	name.hash = full_name_hash(name.name, name.len);
 
 	err = -ENOMEM;
-	dentry = d_alloc(configfs_sb->s_root, &name);
+	dentry = d_alloc(root, &name);
 	if (dentry) {
 		d_add(dentry, NULL);
 
@@ -1714,7 +1718,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
 		}
 	}
 
-	mutex_unlock(&configfs_sb->s_root->d_inode->i_mutex);
+	mutex_unlock(&root->d_inode->i_mutex);
 
 	if (err) {
 		unlink_group(group);
@@ -1728,13 +1732,14 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys)
 {
 	struct config_group *group = &subsys->su_group;
 	struct dentry *dentry = group->cg_item.ci_dentry;
+	struct dentry *root = dentry->d_sb->s_root;
 
-	if (dentry->d_parent != configfs_sb->s_root) {
+	if (dentry->d_parent != root) {
 		printk(KERN_ERR "configfs: Tried to unregister non-subsystem!\n");
 		return;
 	}
 
-	mutex_lock_nested(&configfs_sb->s_root->d_inode->i_mutex,
+	mutex_lock_nested(&root->d_inode->i_mutex,
 			  I_MUTEX_PARENT);
 	mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
 	mutex_lock(&configfs_symlink_mutex);
@@ -1751,7 +1756,7 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys)
 
 	d_delete(dentry);
 
-	mutex_unlock(&configfs_sb->s_root->d_inode->i_mutex);
+	mutex_unlock(&root->d_inode->i_mutex);
 
 	dput(dentry);
 

fs/configfs/inode.c

@@ -44,8 +44,6 @@
 static struct lock_class_key default_group_class[MAX_LOCK_DEPTH];
 #endif
 
-extern struct super_block * configfs_sb;
-
 static const struct address_space_operations configfs_aops = {
 	.readpage	= simple_readpage,
 	.write_begin	= simple_write_begin,
@@ -132,9 +130,10 @@ static inline void set_inode_attr(struct inode * inode, struct iattr * iattr)
 	inode->i_ctime = iattr->ia_ctime;
 }
 
-struct inode *configfs_new_inode(umode_t mode, struct configfs_dirent * sd)
+struct inode *configfs_new_inode(umode_t mode, struct configfs_dirent *sd,
+				 struct super_block *s)
 {
-	struct inode * inode = new_inode(configfs_sb);
+	struct inode * inode = new_inode(s);
 	if (inode) {
 		inode->i_ino = get_next_ino();
 		inode->i_mapping->a_ops = &configfs_aops;
@@ -192,7 +191,7 @@ int configfs_create(struct dentry * dentry, umode_t mode, int (*init)(struct ino
 	if (dentry) {
 		if (!dentry->d_inode) {
 			struct configfs_dirent *sd = dentry->d_fsdata;
-			if ((inode = configfs_new_inode(mode, sd))) {
+			if ((inode = configfs_new_inode(mode, sd, dentry->d_sb))) {
 				if (dentry->d_parent && dentry->d_parent->d_inode) {
 					struct inode *p_inode = dentry->d_parent->d_inode;
 					p_inode->i_mtime = p_inode->i_ctime = CURRENT_TIME;

fs/configfs/mount.c

@@ -38,7 +38,6 @@
 #define CONFIGFS_MAGIC 0x62656570
 
 struct vfsmount * configfs_mount = NULL;
-struct super_block * configfs_sb = NULL;
 struct kmem_cache *configfs_dir_cachep;
 static int configfs_mnt_count = 0;
 
@@ -77,10 +76,9 @@ static int configfs_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_magic = CONFIGFS_MAGIC;
 	sb->s_op = &configfs_ops;
 	sb->s_time_gran = 1;
-	configfs_sb = sb;
 
 	inode = configfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
-				   &configfs_root);
+				   &configfs_root, sb);
 	if (inode) {
 		inode->i_op = &configfs_root_inode_operations;
 		inode->i_fop = &configfs_dir_operations;

fs/configfs/symlink.c

@@ -110,13 +110,13 @@ static int create_link(struct config_item *parent_item,
 
 
 static int get_target(const char *symname, struct path *path,
-		      struct config_item **target)
+		      struct config_item **target, struct super_block *sb)
 {
 	int ret;
 
 	ret = kern_path(symname, LOOKUP_FOLLOW|LOOKUP_DIRECTORY, path);
 	if (!ret) {
-		if (path->dentry->d_sb == configfs_sb) {
+		if (path->dentry->d_sb == sb) {
 			*target = configfs_get_config_item(path->dentry);
 			if (!*target) {
 				ret = -ENOENT;
@@ -158,7 +158,7 @@ int configfs_symlink(struct inode *dir, struct dentry *dentry, const char *symna
 	    !type->ct_item_ops->allow_link)
 		goto out_put;
 
-	ret = get_target(symname, &path, &target_item);
+	ret = get_target(symname, &path, &target_item, dentry->d_sb);
 	if (ret)
 		goto out_put;