From patchwork Fri May 31 16:46:53 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amir Goldstein X-Patchwork-Id: 10970475 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 5258A15E6 for ; Fri, 31 May 2019 16:47:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 43A4928D26 for ; Fri, 31 May 2019 16:47:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 377B628D80; Fri, 31 May 2019 16:47:17 +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 CFCE428D26 for ; Fri, 31 May 2019 16:47:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727030AbfEaQrO (ORCPT ); Fri, 31 May 2019 12:47:14 -0400 Received: from mail-wm1-f66.google.com ([209.85.128.66]:50705 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727003AbfEaQrN (ORCPT ); Fri, 31 May 2019 12:47:13 -0400 Received: by mail-wm1-f66.google.com with SMTP id f204so2453641wme.0; Fri, 31 May 2019 09:47:11 -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=7z+URgKWKe9baBNXTRuiwAT8xxeo4lu6F54jeoU5vwA=; b=LFLr6fmpK1pv59BZ5pGUGCOjYzE4yp97eEuGDDRdFTBA5bMeUpACnEKw54TdDVG58q Gz2KSF+rmusjkhvqwlDCfYITVnz+L4I7qgTMmNnJYQwZmcsoXXGkedodYGm/b5vlsq7q QI1bnRvTW1AYYo4ucUYJQw6pDrPLEOGJLU+XGp1i1HeDDZiP5/zfDM/qX8/9MGwCYy07 LnQ+x7BaBb32uenPLaHeXumiEacQ9shNbhdxfNEtV7eUhsVS4bD8uP17SuGbUrfyj/ej ea3QyVOYRKZJUEJWyDmsRCCC+lX/1AhYgSmhqz8thB8aj1sZL6dZ4d6VCCSqQXu5fHED j+YA== 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=7z+URgKWKe9baBNXTRuiwAT8xxeo4lu6F54jeoU5vwA=; b=E5vNR6YikYgL+3bUQhTtTa6RsQ+rHjhg1GJEy+2WmFX+A/yaejGsCNIkmAeSUdm3rJ tX4fDg12SVi8aAymFCrIQhWl3iDvv4jD5RrnMSu4UU8vF59SKm01UR8OFNLSNoLPRd97 NpjjQdQJ8MYmLKDuKHcGt+bgM+PCvyHau7ba4WEpsq/ah1AioTlUZrtGSJCnNwYHfSiI LzLAKAJ54jRqg3j5CYakMHy1TPJY4ZDrbyY+LSohZql9eZkY41YIPm71Ei5d3GSx3gUI Zo+G/pTUut0fMtOYdmm5cwqTmbnNvVPJbfieP5jpgAeN2jelpqjzXNbGmvPWK0R2xuU7 Jj+g== X-Gm-Message-State: APjAAAWvF6TFUggC1pr9XfuAeMf+c4WIQzEKSZmBSYQq3sX+TBh+MMGt BU+/SBNj1ec5kj8j7MIXdbA= X-Google-Smtp-Source: APXvYqz3T4EEheFeEouY+WuKNMAIR95jioZXVsKQWFBS1fa+ziG4bTL0aCq8vUDOoku1rSk0AKcxlg== X-Received: by 2002:a1c:f606:: with SMTP id w6mr6665229wmc.130.1559321230954; Fri, 31 May 2019 09:47:10 -0700 (PDT) Received: from localhost.localdomain ([5.102.238.208]) by smtp.gmail.com with ESMTPSA id n5sm7669593wrj.27.2019.05.31.09.47.09 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 31 May 2019 09:47:10 -0700 (PDT) From: Amir Goldstein To: "Darrick J . Wong" Cc: Dave Chinner , Christoph Hellwig , linux-xfs@vger.kernel.org, Olga Kornievskaia , Luis Henriques , Al Viro , linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, ceph-devel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, Dave Chinner Subject: [PATCH v4 1/9] vfs: introduce generic_copy_file_range() Date: Fri, 31 May 2019 19:46:53 +0300 Message-Id: <20190531164701.15112-2-amir73il@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190531164701.15112-1-amir73il@gmail.com> References: <20190531164701.15112-1-amir73il@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: Dave Chinner Right now if vfs_copy_file_range() does not use any offload mechanism, it falls back to calling do_splice_direct(). This fails to do basic sanity checks on the files being copied. Before we start adding this necessarily functionality to the fallback path, separate it out into generic_copy_file_range(). generic_copy_file_range() has the same prototype as ->copy_file_range() so that filesystems can use it in their custom ->copy_file_range() method if they so choose. Signed-off-by: Dave Chinner Signed-off-by: Amir Goldstein Reviewed-by: Darrick J. Wong --- fs/read_write.c | 35 ++++++++++++++++++++++++++++++++--- include/linux/fs.h | 3 +++ 2 files changed, 35 insertions(+), 3 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index c543d965e288..676b02fae589 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1565,6 +1565,36 @@ COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, } #endif +/** + * generic_copy_file_range - copy data between two files + * @file_in: file structure to read from + * @pos_in: file offset to read from + * @file_out: file structure to write data to + * @pos_out: file offset to write data to + * @len: amount of data to copy + * @flags: copy flags + * + * This is a generic filesystem helper to copy data from one file to another. + * It has no constraints on the source or destination file owners - the files + * can belong to different superblocks and different filesystem types. Short + * copies are allowed. + * + * This should be called from the @file_out filesystem, as per the + * ->copy_file_range() method. + * + * Returns the number of bytes copied or a negative error indicating the + * failure. + */ + +ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + size_t len, unsigned int flags) +{ + return do_splice_direct(file_in, &pos_in, file_out, &pos_out, + len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0); +} +EXPORT_SYMBOL(generic_copy_file_range); + /* * copy_file_range() differs from regular file read and write in that it * specifically allows return partial success. When it does so is up to @@ -1632,9 +1662,8 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, goto done; } - ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out, - len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0); - + ret = generic_copy_file_range(file_in, pos_in, file_out, pos_out, len, + flags); done: if (ret > 0) { fsnotify_access(file_in); diff --git a/include/linux/fs.h b/include/linux/fs.h index f7fdfe93e25d..ea17858310ff 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1889,6 +1889,9 @@ extern ssize_t vfs_readv(struct file *, const struct iovec __user *, unsigned long, loff_t *, rwf_t); extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *, loff_t, size_t, unsigned int); +extern ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + size_t len, unsigned int flags); extern int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, loff_t *count,