switch fat to ->s_d_op, close exportfs races there

don't bother with lock_super() in fat_fill_super() callers, while
we are at it - there won't be any concurrency anyway.

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

1 files changed, 9 insertions, 18 deletions

diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index e3ffc5e12332..f88f752babd9 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -772,13 +772,10 @@ static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry,
 
 out:
         unlock_super(sb);
-        d_set_d_op(dentry, sb->s_root->d_op);
         dentry->d_time = dentry->d_parent->d_inode->i_version;
         dentry = d_splice_alias(inode, dentry);
-        if (dentry) {
-                d_set_d_op(dentry, sb->s_root->d_op);
+        if (dentry)
                 dentry->d_time = dentry->d_parent->d_inode->i_version;
-        }
         return dentry;
 
 error:
@@ -1066,24 +1063,18 @@ static const struct inode_operations vfat_dir_inode_operations = {
         .getattr        = fat_getattr,
 };
 
-static int vfat_fill_super(struct super_block *sb, void *data, int silent)
+static void setup(struct super_block *sb)
 {
-        int res;
-
-        lock_super(sb);
-        res = fat_fill_super(sb, data, silent, &vfat_dir_inode_operations, 1);
-        if (res) {
-                unlock_super(sb);
-                return res;
-        }
-
         if (MSDOS_SB(sb)->options.name_check != 's')
-                d_set_d_op(sb->s_root, &vfat_ci_dentry_ops);
+                sb->s_d_op = &vfat_ci_dentry_ops;
         else
-                d_set_d_op(sb->s_root, &vfat_dentry_ops);
+                sb->s_d_op = &vfat_dentry_ops;
+}
 
-        unlock_super(sb);
-        return 0;
+static int vfat_fill_super(struct super_block *sb, void *data, int silent)
+{
+        return fat_fill_super(sb, data, silent, &vfat_dir_inode_operations,
+                             1, setup);
 }
 
 static struct dentry *vfat_mount(struct file_system_type *fs_type,