From mboxrd@z Thu Jan 1 00:00:00 1970 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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 84685C433DF for ; Sat, 13 Jun 2020 13:05:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 657952074D for ; Sat, 13 Jun 2020 13:05:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="gWI7xlbh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726361AbgFMNFE (ORCPT ); Sat, 13 Jun 2020 09:05:04 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:60678 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726045AbgFMNFD (ORCPT ); Sat, 13 Jun 2020 09:05:03 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592053502; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=8Vkn3rEZeq1POego0MCBFrp41m1L5KDYoTSqj0fJLmA=; b=gWI7xlbhDlVweI7PNSB7xyzr2CpBMjdUitYumLvlIOoNd5TsjcMJNU9LRPDSpNzQiD8QI+ WAQkQyHT2ZyGGogZKWL87y5JJC6qPvU7kJmfVq2pRUU5VpUFL3CcrOBEe4dLJiXlIgWBAV G6ADfszgCF/QFANnsWXusnpg/5UwhZ8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-59-2oUBF2pBMki-cnGHOZyJkg-1; Sat, 13 Jun 2020 09:04:58 -0400 X-MC-Unique: 2oUBF2pBMki-cnGHOZyJkg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 70B02107ACCA; Sat, 13 Jun 2020 13:04:56 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-114-66.rdu2.redhat.com [10.10.114.66]) by smtp.corp.redhat.com (Postfix) with ESMTP id 75D905D9C5; Sat, 13 Jun 2020 13:04:53 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <1503686.1591113304@warthog.procyon.org.uk> <20200610111256.s47agmgy5gvj3zwz@ws.net.home> To: Linus Torvalds Cc: dhowells@redhat.com, Karel Zak , Al Viro , dray@redhat.com, Miklos Szeredi , Steven Whitehouse , Jeff Layton , Ian Kent , andres@anarazel.de, Christian Brauner , Jarkko Sakkinen , keyrings@vger.kernel.org, linux-fsdevel , Linux Kernel Mailing List Subject: Re: [GIT PULL] General notification queue and key notifications MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <3984624.1592053492.1@warthog.procyon.org.uk> Date: Sat, 13 Jun 2020 14:04:52 +0100 Message-ID: <3984625.1592053492@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Linus Torvalds wrote: > I'm not even convinced O_NOTIFICATION_PIPE is necessary, but at worst > it will be a useful marker. I think the only real reason for it was to > avoid any clashes with splice(), which has more complex use of the > pipe buffers. The main reason is to prevent splice because the iov_iter rewind for splice gets quite tricky if the kernel can randomly insert packets into the pipe buffer in between what splice is inserting. > I'm so far just reading this thread and the arguments for users, and I > haven't yet looked at all the actual details in the pull request - but > last time I had objections to things it wasn't the code, it was the > lack of any use. Would you be willing at this point to consider pulling the mount notifications and fsinfo() which helps support that? I could whip up pull reqs for those two pieces - or do you want to see more concrete patches that use it? David