staging: lustre: mdt: disable IMA support

For IMA (Integrity Measurement Architecture), there are two xattr
"security.ima" and "security.evm" to protect the file to be modified
accidentally or maliciously, the two xattr are not compatible with
VBR, then disable it to workaround the problem currently and enable
it when the conditions are ready.
Signed-off-by: Hongchao Zhang <hongchao.zhang@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6455
Reviewed-on: http://review.whamcloud.com/14928Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/llite/xattr.c

@@ -126,6 +126,11 @@ ll_xattr_set_common(const struct xattr_handler *handler,
 	    strcmp(name, "selinux") == 0)
 		return -EOPNOTSUPP;
 
+	/*FIXME: enable IMA when the conditions are ready */
+	if (handler->flags == XATTR_SECURITY_T &&
+	    (!strcmp(name, "ima") || !strcmp(name, "evm")))
+		return -EOPNOTSUPP;
+
 	sprintf(fullname, "%s%s\n", handler->prefix, name);
 	rc = md_setxattr(sbi->ll_md_exp, ll_inode2fid(inode),
 			 valid, fullname, pv, size, 0, flags,