fs/ufs: remove unused ufs_super_block_second pointer

[firefly-linux-kernel-4.4.55.git] / fs / kernfs / mount.c

diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c
index 0d6ce895a9eec0ce3b3329d1353b594d353aeacb..6a5f04ac87040d85179420d254d528789ddcf1d6 100644 (file)
--- a/fs/kernfs/mount.c
+++ b/fs/kernfs/mount.c
@@ -19,12 +19,49 @@
 
 struct kmem_cache *kernfs_node_cache;
 
-static const struct super_operations kernfs_sops = {
+static int kernfs_sop_remount_fs(struct super_block *sb, int *flags, char *data)
+{
+       struct kernfs_root *root = kernfs_info(sb)->root;
+       struct kernfs_syscall_ops *scops = root->syscall_ops;
+
+       if (scops && scops->remount_fs)
+               return scops->remount_fs(root, flags, data);
+       return 0;
+}
+
+static int kernfs_sop_show_options(struct seq_file *sf, struct dentry *dentry)
+{
+       struct kernfs_root *root = kernfs_root(dentry->d_fsdata);
+       struct kernfs_syscall_ops *scops = root->syscall_ops;
+
+       if (scops && scops->show_options)
+               return scops->show_options(sf, root);
+       return 0;
+}
+
+const struct super_operations kernfs_sops = {
        .statfs         = simple_statfs,
        .drop_inode     = generic_delete_inode,
        .evict_inode    = kernfs_evict_inode,
+
+       .remount_fs     = kernfs_sop_remount_fs,
+       .show_options   = kernfs_sop_show_options,
 };
 
+/**
+ * kernfs_root_from_sb - determine kernfs_root associated with a super_block
+ * @sb: the super_block in question
+ *
+ * Return the kernfs_root associated with @sb.  If @sb is not a kernfs one,
+ * %NULL is returned.
+ */
+struct kernfs_root *kernfs_root_from_sb(struct super_block *sb)
+{
+       if (sb->s_op == &kernfs_sops)
+               return kernfs_info(sb)->root;
+       return NULL;
+}
+
 static int kernfs_fill_super(struct super_block *sb)
 {
        struct kernfs_super_info *info = kernfs_info(sb);
@@ -94,6 +131,7 @@ const void *kernfs_super_ns(struct super_block *sb)
  * @fs_type: file_system_type of the fs being mounted
  * @flags: mount flags specified for the mount
  * @root: kernfs_root of the hierarchy being mounted
+ * @new_sb_created: tell the caller if we allocated a new superblock
  * @ns: optional namespace tag of the mount
  *
  * This is to be called from each kernfs user's file_system_type->mount()
@@ -104,7 +142,8 @@ const void *kernfs_super_ns(struct super_block *sb)
  * The return value can be passed to the vfs layer verbatim.
  */
 struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags,
-                              struct kernfs_root *root, const void *ns)
+                              struct kernfs_root *root, bool *new_sb_created,
+                              const void *ns)
 {
        struct super_block *sb;
        struct kernfs_super_info *info;
@@ -122,6 +161,10 @@ struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags,
                kfree(info);
        if (IS_ERR(sb))
                return ERR_CAST(sb);
+
+       if (new_sb_created)
+               *new_sb_created = !sb->s_root;
+
        if (!sb->s_root) {
                error = kernfs_fill_super(sb);
                if (error) {