This review is not for erofs specifically, but for all file systems using
the same scheme.
> +static const char *erofs_xattr_prefix(int xattr_index, struct dentry *dentry)
> +{
> + const char *name = NULL;
> + const struct xattr_handler *handler = NULL;
> +
> + switch (xattr_index) {
> + case EROFS_XATTR_INDEX_USER:
> + handler = &erofs_xattr_user_handler;
> + break;
> + case EROFS_XATTR_INDEX_TRUSTED:
> + handler = &erofs_xattr_trusted_handler;
> + break;
> +#ifdef CONFIG_EROFS_FS_SECURITY
> + case EROFS_XATTR_INDEX_SECURITY:
> + handler = &erofs_xattr_security_handler;
> + break;
> +#endif
> +#ifdef CONFIG_EROFS_FS_POSIX_ACL
> + case EROFS_XATTR_INDEX_POSIX_ACL_ACCESS:
> + if (posix_acl_dentry_list(dentry))
> + name = XATTR_NAME_POSIX_ACL_ACCESS;
> + break;
> + case EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT:
> + if (posix_acl_dentry_list(dentry))
> + name = XATTR_NAME_POSIX_ACL_DEFAULT;
> + break;
> +#endif
> + default:
> + return NULL;
> + }
> +
> + if (xattr_dentry_list(handler, dentry))
> + name = xattr_prefix(handler);
I'm not a huge fan of all this duplicate logic in the file systems
that is more verbose and a bit confusing. Until we remove the
xattr handlers entirely, I wonder if we just need to keep a
special ->list for posix xattrs, just to be able to keep the
old logic in all these file system. That is a ->list that
works for xattr_dentry_list, but never actually lists anything.
That would remove all this boiler plate for now without minimal
core additions. Eventually we can hopefully remove first ->list
and then the xattr handlers entirely, but until then this seems
like a step backwards.
