From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ms.lwn.net ([45.79.88.28]:40396 "EHLO ms.lwn.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732411AbeGKP5B (ORCPT ); Wed, 11 Jul 2018 11:57:01 -0400 Date: Wed, 11 Jul 2018 09:51:59 -0600 From: Jonathan Corbet To: David Howells Cc: viro@zeniv.linux.org.uk, linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 24/32] vfs: syscall: Add fsopen() to prepare for superblock creation [ver #9] Message-ID: <20180711095159.08e5435c@lwn.net> In-Reply-To: <153126264966.14533.3388004240803696769.stgit@warthog.procyon.org.uk> References: <153126248868.14533.9751473662727327569.stgit@warthog.procyon.org.uk> <153126264966.14533.3388004240803696769.stgit@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Tue, 10 Jul 2018 23:44:09 +0100 David Howells wrote: > sfd = fsopen("ext4", FSOPEN_CLOEXEC); > write(sfd, "s /dev/sdb1"); // note I'm ignoring write's length arg > write(sfd, "o noatime"); > write(sfd, "o acl"); > write(sfd, "o user_attr"); > write(sfd, "o iversion"); > write(sfd, "o "); > write(sfd, "r /my/container"); // root inside the fs > write(sfd, "x create"); // create the superblock A minor detail but ... the "r" operation mentioned above is not actually implemented in this system call. jon