namespaces: move proc_net_get_sb to a generic fs/super.c helper

[safe/jmp/linux-2.6] / fs / super.c

diff --git a/fs/super.c b/fs/super.c
index 77cb4ec..786fe7d 100644 (file)
--- a/fs/super.c
+++ b/fs/super.c
@@ -771,6 +771,46 @@ void kill_litter_super(struct super_block *sb)
 
 EXPORT_SYMBOL(kill_litter_super);
 
+static int ns_test_super(struct super_block *sb, void *data)
+{
+       return sb->s_fs_info == data;
+}
+
+static int ns_set_super(struct super_block *sb, void *data)
+{
+       sb->s_fs_info = data;
+       return set_anon_super(sb, NULL);
+}
+
+int get_sb_ns(struct file_system_type *fs_type, int flags, void *data,
+       int (*fill_super)(struct super_block *, void *, int),
+       struct vfsmount *mnt)
+{
+       struct super_block *sb;
+
+       sb = sget(fs_type, ns_test_super, ns_set_super, data);
+       if (IS_ERR(sb))
+               return PTR_ERR(sb);
+
+       if (!sb->s_root) {
+               int err;
+               sb->s_flags = flags;
+               err = fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
+               if (err) {
+                       up_write(&sb->s_umount);
+                       deactivate_super(sb);
+                       return err;
+               }
+
+               sb->s_flags |= MS_ACTIVE;
+       }
+
+       simple_set_mnt(mnt, sb);
+       return 0;
+}
+
+EXPORT_SYMBOL(get_sb_ns);
+
 #ifdef CONFIG_BLOCK
 static int set_bdev_super(struct super_block *s, void *data)
 {