From patchwork Wed Oct 24 19:58:25 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Olga Kornievskaia X-Patchwork-Id: 10654935 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B5E4714E2 for ; Wed, 24 Oct 2018 19:58:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A4CE22AFD5 for ; Wed, 24 Oct 2018 19:58:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 994EB2AFE6; Wed, 24 Oct 2018 19:58:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 51F052AFD5 for ; Wed, 24 Oct 2018 19:58:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727361AbeJYE2K (ORCPT ); Thu, 25 Oct 2018 00:28:10 -0400 Received: from mail-qk1-f194.google.com ([209.85.222.194]:46613 "EHLO mail-qk1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726221AbeJYE2K (ORCPT ); Thu, 25 Oct 2018 00:28:10 -0400 Received: by mail-qk1-f194.google.com with SMTP id a193-v6so4209626qkc.13; Wed, 24 Oct 2018 12:58:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=OalLXzSog1uf5ATRS1HbAFJ8toxAhnJN/f8XiubBLbA=; b=Al64WyJ3+yyMsTNXcu7/1veAld9d0g0HyTIZECjKoYiN1LMpQj5KchudMIGqL8kzde bcqKMsmKHgWeizagKzcGfmnVLf/bj5+JSiW7QunT9Z1usVe4qqUO8BIrgi4SliWLG+ie 5J9gqnkLJLL3PJw3hn3JPJTpAIA7edF33FGKX4NyBtYX40amPO6wHbP6tS78W31o296m g8zDopsRLT7Vh69XzWh6i3jlqui5YJEjp2Gt3kerBt5lX8pmb2aG2M4I5AebchlRpii+ WgWZI81n1qdlJS8EmZr9bUkt5xNxxZvBcsjmjhuxSNNmGkHiGq/8RZMiCV2C9NGABH0e +mQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=OalLXzSog1uf5ATRS1HbAFJ8toxAhnJN/f8XiubBLbA=; b=N9JjE14UXIfHm8+UeQndWRWzBUHRREgHcyPF4uJO6qippHVRXZg4JjHOMFWetjyb0p xJME2z0d4h1OQeSWc2Ch69XwefBEHCAAEtQJATf8u29VZ62XjrJTtaQZmMKpnMOpfEZl MugQmwKWxYvJxlssdymKytawbRVFyzkWyAGT8ZSZ6w9shhT8ct3jxjT7zR/hPR7rzkJo 5q2aXGcPlOeOo06Tpqs+BDLEF47qNvGRqsv9Y6wfBN7ImDSRaz3Brht/xqKutu8eNS6s 8Yjd+Z5rCT/08CkIDiOcLJj4813ea/ZsfQ/skyOJyL3vSpcXjiVRBnmSoN4FfHQiXJW4 vxog== X-Gm-Message-State: AGRZ1gLxirFQ/ICNPWuCWJ2kVG5iZilcG3sBiytJ11wwDw0GP8pJVqD0 +ksx2IOse961ld5a8ZXCdPA= X-Google-Smtp-Source: AJdET5dCfTz4bUm3iUVrkd0hTuIEjsr5SJ4YzkRDhuDs+NxdDoom/escgMLMcrpcE0cnCEV9PKA3kg== X-Received: by 2002:ae9:e515:: with SMTP id w21-v6mr3724872qkf.105.1540411123023; Wed, 24 Oct 2018 12:58:43 -0700 (PDT) Received: from Olgas-MBP-195.attlocal.net (172-10-226-31.lightspeed.livnmi.sbcglobal.net. [172.10.226.31]) by smtp.gmail.com with ESMTPSA id d124-v6sm3872380qkf.85.2018.10.24.12.58.41 (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 24 Oct 2018 12:58:42 -0700 (PDT) From: Olga Kornievskaia To: trond.myklebust@hammerspace.com, anna.schumaker@netapp.com, viro@zeniv.linux.org.uk, smfrench@gmail.com, miklos@szeredi.hu Cc: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-cifs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-man@vger.kernel.org Subject: [PATCH 1/1] man-page: copy_file_range(2) allow for cross-device copies Date: Wed, 24 Oct 2018 15:58:25 -0400 Message-Id: <20181024195837.35532-3-olga.kornievskaia@gmail.com> X-Mailer: git-send-email 2.10.1 (Apple Git-78) In-Reply-To: <20181024195837.35532-1-olga.kornievskaia@gmail.com> References: <20181024195837.35532-1-olga.kornievskaia@gmail.com> Sender: linux-cifs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Olga Kornievskaia A proposed VFS change removes the check for the files to reside under the same file system. Instead, a file system driver implementation is allowed to perform a cross-device copy_file_range() and if the file system fails to support it instead fallback to doing a do_splice copy. Therefore, EXDEV is no longer a possible error. Signed-off-by: Olga Kornievskaia --- man2/copy_file_range.2 | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/man2/copy_file_range.2 b/man2/copy_file_range.2 index 20374ab..723b2d0 100644 --- a/man2/copy_file_range.2 +++ b/man2/copy_file_range.2 @@ -39,7 +39,8 @@ The .BR copy_file_range () system call performs an in-kernel copy between two file descriptors without the additional cost of transferring data from the kernel to user space -and then back into the kernel. +and then back into the kernel. Since kernel version 4.21(???) passed in +file descriptors are not required to be under the same mounted file system. It copies up to .I len bytes of data from file descriptor @@ -128,10 +129,6 @@ Out of memory. .B ENOSPC There is not enough space on the target filesystem to complete the copy. .TP -.B EXDEV -The files referred to by -.IR file_in " and " file_out -are not on the same mounted filesystem. .SH VERSIONS The .BR copy_file_range ()