From owner-freebsd-hackers@freebsd.org Fri Apr 13 02:40:07 2018 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 9F9C0F82729 for ; Fri, 13 Apr 2018 02:40:07 +0000 (UTC) (envelope-from theron.tarigo@gmail.com) Received: from mail-yb0-x22e.google.com (mail-yb0-x22e.google.com [IPv6:2607:f8b0:4002:c09::22e]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 30B9C784D0 for ; Fri, 13 Apr 2018 02:40:07 +0000 (UTC) (envelope-from theron.tarigo@gmail.com) Received: by mail-yb0-x22e.google.com with SMTP id c1-v6so3417822ybm.2 for ; Thu, 12 Apr 2018 19:40:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:subject:from:to:cc:references:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=E9guRet8n09kYw7LT68IPT+0Cf4V9tjb6vkW9EXk2N0=; b=uMfylPnK6rMTsQDJ7xXMiAZyUmOoN77iuv0V+9bNvEwwWG3W9G1jIIbd2sKGtnPCdy CiCdD64S3vSLXK5aOUN3RLXyfOvVk9mk8JZdbeKJ6K0ab7HYNp3zZ6tjzrHHwCfGaTK0 FVjI/2dBK9mpyOF7hT+oCYuRuczHiEG2E966iOrHANcTS40adAlSyMq4yeGKVnoTPE0t 3dr+USjxmVQmNmvLHKVYBXbBGFBHwqNV3zPGycBz3Wa3JPeLEbYpM+orevYEjRaPXW64 VbtcKzJcSObQ3IMungKsk38sXwkl5jq1aT8Sb6koqO+2j1P6AUfSQFZHrHrrFQbakDfs pX8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:subject:from:to:cc:references:message-id :date:user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=E9guRet8n09kYw7LT68IPT+0Cf4V9tjb6vkW9EXk2N0=; b=AWvjOhec3xwJddSSHsoGz7RT1MQ83xa6BvTbBP7KFu5TbNSLqJg8400NtdI8v6hlQK Kw8MUWuouoFsyPawN7Irl3Csk0q/TKPTg3rBQrUU0rHfR5T6nxEY7XGzph1f7p5xpRuV msZyImEF+bMrFhUE4/ZP40bGm5G6mnmEzj+3VLLMTpuyR+ukCUVdS2mX01OPTnQF3Uof 0kNB8NLWUueW9F8YoEvDnaSGU5bht9EjFjliB3A+AkitDbOZN19YOQt7q0MGYsGyTG8A l/YhiK5i8npIchbx3gIgwmVc1HMr/XcOFDeFMFMvUgDKwor0h/qvbgXxBq7lu5/uQq+G pqgQ== X-Gm-Message-State: ALQs6tAWxvQ8HNokqZAICU4CCbFcSOicxB0Z06yPUkhAYZnvRaXGoO2N gsPK52w8ykAzffhEDh8SDyQ5ozZV X-Google-Smtp-Source: AIpwx4+EO+LZ6nEUAVkkkcrIK5BvGw4A7wEFj1uMzHyI88Rphr/FXTrQXmzwYzuyb0E8476YSmO3CQ== X-Received: by 2002:a25:8e09:: with SMTP id p9-v6mr2809240ybl.352.1523587206613; Thu, 12 Apr 2018 19:40:06 -0700 (PDT) Received: from [168.122.154.98] (dhcp-resnet-168-122-154-98.bu.edu. [168.122.154.98]) by smtp.gmail.com with ESMTPSA id m53sm4292832qtf.67.2018.04.12.19.40.06 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 12 Apr 2018 19:40:06 -0700 (PDT) Sender: Theron Tarigo Subject: Re: mount system call for nullfs From: Theron Tarigo To: Alfonso Sabato Siciliano Cc: freebsd-hackers@freebsd.org References: <76f78cee-e62a-67fb-3d84-e420c50a4ba1@gmail.com> Message-ID: <7edc3b8a-5278-dcfb-538e-a9d968dde9fc@gmail.com> Date: Thu, 12 Apr 2018 22:40:05 -0400 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <76f78cee-e62a-67fb-3d84-e420c50a4ba1@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Apr 2018 02:40:07 -0000 Sorry, I notice now this: On 04/12/18 21:30, Alfonso Sabato Siciliano wrote: > (the implementation of mount_nullfs(8) uses nmount syscall so it is not > usefulI; Why would mount instead of nmount be more useful? /usr/src/sbin/mount/mount.c notes that         /* XXX: We need to get away from implementing external mount          *      programs for every filesystem, and move towards having          *      each filesystem properly implement the nmount() system call.          */ It might be that mount_nullfs only works at the moment with the nmount-based implementation, in which case you would need to work around this.