From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f198.google.com (mail-wr0-f198.google.com [209.85.128.198]) by kanga.kvack.org (Postfix) with ESMTP id AF4936B0038 for ; Sun, 2 Apr 2017 09:36:32 -0400 (EDT) Received: by mail-wr0-f198.google.com with SMTP id l43so20650716wre.4 for ; Sun, 02 Apr 2017 06:36:32 -0700 (PDT) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id h34si16035922wrh.233.2017.04.02.06.36.30 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 02 Apr 2017 06:36:31 -0700 (PDT) Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v32DXXjm071582 for ; Sun, 2 Apr 2017 09:36:29 -0400 Received: from e06smtp11.uk.ibm.com (e06smtp11.uk.ibm.com [195.75.94.107]) by mx0b-001b2d01.pphosted.com with ESMTP id 29jyf0nepw-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Sun, 02 Apr 2017 09:36:29 -0400 Received: from localhost by e06smtp11.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sun, 2 Apr 2017 14:36:27 +0100 From: Mike Rapoport Subject: [PATCH for 4.11] userfaultfd: report actual registered features in fdinfo Date: Sun, 2 Apr 2017 16:36:21 +0300 Message-Id: <1491140181-22121-1-git-send-email-rppt@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Andrea Arcangeli , Pavel Emelyanov , linux-mm@kvack.org, Mike Rapoport fdinfo for userfault file descriptor reports UFFD_API_FEATURES. Up until recently, the UFFD_API_FEATURES was defined as 0, therefore corresponding field in fdinfo always contained zero. Now, with introduction of several additional features, UFFD_API_FEATURES is not longer 0 and it seems better to report actual features requested for the userfaultfd object described by the fdinfo. First, the applications that were using userfault will still see zero at the features field in fdinfo. Next, reporting actual features rather than available features, gives clear indication of what userfault features are used by an application. Signed-off-by: Mike Rapoport --- fs/userfaultfd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 1d227b0..f7555fc 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1756,7 +1756,7 @@ static void userfaultfd_show_fdinfo(struct seq_file *m, struct file *f) * protocols: aa:... bb:... */ seq_printf(m, "pending:\t%lu\ntotal:\t%lu\nAPI:\t%Lx:%x:%Lx\n", - pending, total, UFFD_API, UFFD_API_FEATURES, + pending, total, UFFD_API, ctx->features, UFFD_API_IOCTLS|UFFD_API_RANGE_IOCTLS); } #endif -- 1.9.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org