From patchwork Tue Apr 20 22:08:04 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Axel Rasmussen X-Patchwork-Id: 12215125 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 78EA3C4360C for ; Tue, 20 Apr 2021 22:08:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 49650613E6 for ; Tue, 20 Apr 2021 22:08:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234398AbhDTWJP (ORCPT ); Tue, 20 Apr 2021 18:09:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40448 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234330AbhDTWJC (ORCPT ); Tue, 20 Apr 2021 18:09:02 -0400 Received: from mail-qv1-xf49.google.com (mail-qv1-xf49.google.com [IPv6:2607:f8b0:4864:20::f49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA45FC061348 for ; Tue, 20 Apr 2021 15:08:27 -0700 (PDT) Received: by mail-qv1-xf49.google.com with SMTP id l61-20020a0c84430000b02901a9a7e363edso4147406qva.16 for ; Tue, 20 Apr 2021 15:08:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=+mbkINT23NQwVcWMsgi99GnmaMWJZnHq8mB1mAGG8Zs=; b=po9ArG7ZdtzYVDcv5vyMGKJeuPtnghxwSIn+gUjtsSZPemrE/klwSLC5Hm14ZzmVBr J4fsL1TqZkclrXJQjUYboxz/RZII5pyYDh6HnkqPk414pWLjG4kpolNiR9s75do6g2Pr DpY3NvwNL7a+rT74p+SLBJs1f45c6PET88l3inft/kpGjTYvvhQIjy7gAGRUbiwr4Fv2 2Q7p3yMlGf9aUzi7Tio8EON2fR6Vu88aq+LcqtbIUmOgkVbX/B3Am1bivGu/zj7wXnBW aW6henJINq/oy28fXQsFp37HYoat5FM6j15ZtXY1rxjN5oKqtEd6dQFDNqVQnNPT/ZSQ kwZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=+mbkINT23NQwVcWMsgi99GnmaMWJZnHq8mB1mAGG8Zs=; b=Huz20MbrTJR2KyD7t/1fjWBTlvlkrzesXQ4JL9l+M/J72iC/bUF8UkleYRp1LVXVY1 OnVtpOHXqzRhTHhjmcWs4uGl7fcpgaCDwmCYr7Gh4wxJoKo5fqyK1mJ9dDIrYnbLJGXx UcuUbYTqTzA/j1GC3e0RQzpfdhA9p7EWAe3CrrlJrViSbhpDkOqXQGTFMROWHstPBcH6 uUL8IrFnCTBlH/tcfsOZ6CPZUWs/6s6rtomY+14cFp7f1gLVr7+SyzpW1crZABY5vOXX HnJZpgwsU9eoBpHg3hD1cbUPPs2MqkJrqE1S4hmbd/b154Rv3CNObfeokRXs6u/U59sY ScuA== X-Gm-Message-State: AOAM533Ju5vu2oJGhbGg5wItsSJ+CJFg+33kQNKSSk8PJfrUl7wUDjgt 9aazbf0PZSXzPmcWZTngywaf+iDVPjUyiUZcwulu X-Google-Smtp-Source: ABdhPJzDCW1ZTwiCo7QhfK6grPFLercdg6lvY5/FYqbdhC5uCIc0YWN0hcRTy+dnp5ILgkSMhBf0eQ1k/vGiUVro3wEN X-Received: from ajr0.svl.corp.google.com ([2620:15c:2cd:203:c40e:ee2c:2ab8:257a]) (user=axelrasmussen job=sendgmr) by 2002:ad4:4944:: with SMTP id o4mr29064929qvy.18.1618956506891; Tue, 20 Apr 2021 15:08:26 -0700 (PDT) Date: Tue, 20 Apr 2021 15:08:04 -0700 In-Reply-To: <20210420220804.486803-1-axelrasmussen@google.com> Message-Id: <20210420220804.486803-11-axelrasmussen@google.com> Mime-Version: 1.0 References: <20210420220804.486803-1-axelrasmussen@google.com> X-Mailer: git-send-email 2.31.1.368.gbe11c130af-goog Subject: [PATCH v4 10/10] userfaultfd: update documentation to mention shmem minor faults From: Axel Rasmussen To: Alexander Viro , Andrea Arcangeli , Andrew Morton , Hugh Dickins , Jerome Glisse , Joe Perches , Lokesh Gidra , Mike Kravetz , Mike Rapoport , Peter Xu , Shaohua Li , Shuah Khan , Stephen Rothwell , Wang Qing Cc: linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Axel Rasmussen , Brian Geffon , "Dr . David Alan Gilbert" , Mina Almasry , Oliver Upton Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Generally, the documentation we wrote for hugetlbfs-based minor faults still all applies. The only missing piece is to mention the new feature flag which indicates that the kernel supports this for shmem as well. Signed-off-by: Axel Rasmussen Acked-by: Hugh Dickins --- Documentation/admin-guide/mm/userfaultfd.rst | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/mm/userfaultfd.rst b/Documentation/admin-guide/mm/userfaultfd.rst index 3aa38e8b8361..6528036093e1 100644 --- a/Documentation/admin-guide/mm/userfaultfd.rst +++ b/Documentation/admin-guide/mm/userfaultfd.rst @@ -77,7 +77,8 @@ events, except page fault notifications, may be generated: - ``UFFD_FEATURE_MINOR_HUGETLBFS`` indicates that the kernel supports ``UFFDIO_REGISTER_MODE_MINOR`` registration for hugetlbfs virtual memory - areas. + areas. ``UFFD_FEATURE_MINOR_SHMEM`` is the analogous feature indicating + support for shmem virtual memory areas. The userland application should set the feature flags it intends to use when invoking the ``UFFDIO_API`` ioctl, to request that those features be