From patchwork Wed May 29 17:43:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amir Goldstein X-Patchwork-Id: 1107294 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-cifs-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="KirtEW/O"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45DdNk5Qmtz9sBr for ; Thu, 30 May 2019 03:43:34 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726245AbfE2Rnd (ORCPT ); Wed, 29 May 2019 13:43:33 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:33882 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726205AbfE2Rnc (ORCPT ); Wed, 29 May 2019 13:43:32 -0400 Received: by mail-wr1-f66.google.com with SMTP id f8so2421338wrt.1; Wed, 29 May 2019 10:43:30 -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=KirtEW/OGmn/qiY+9wme5Gh5KIVAoljOuFx+nMJamoVSeYIrxdiMzYn5QLUjJMNJI6 uozf24MrBZM0dh6RM6ilar+ioPNQplygnIYbQIwa/ooqLWPqBuBrhlnV2e3V9HQ4h/U9 XehykFGHiUsLCVmkzhfm/g2TAxLfNksM6q/YBky875wc79vfxcR/woBE98CUs3G1oZJD YwkLoRKuk/Piz4QruovX3eZYqXkGG8szNks90JbPDg8zJiAYTUAqJ/4w4TO0qDTuFFAn jrtwm0R+s8pM5yemqSKfFpK++gJfbK3DIbyxZfQfY74slW/PepSLQZFSEs5z6x0xMAoU +5gg== 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=ddMImk2vUJtWqV1qabtcdIqysuUbwayZ5EOFZHOAlumZ4lzec7wM03HWvnIPIAuN5Y xT+QLeu1KJ21CZOu04ElVQxkpYtITOR1VMwBWBzb5Ow3kw9e7DYa3uUefljVwr+nHODU 1Q8NqsdPCr2UlFtVzgRNODb9zn1xXOjUdTTW6ivfR/S6D7BuWbrORrSYz8wYxvlXvYKr pAzrVjuc84GWH0vPiF8dAtIGi9F0BnCay0cReA6sIDBs+TkY86d9jDgLahun0OkLJpF5 n6NR3Cu2SgefkAO8NPieQpO6Baq0NS+b/0T+Boc5WBgYcQwz0sopHnQ2zbdqQrYfmJqD KXDA== X-Gm-Message-State: APjAAAUQ8O8/W7qf6gvnsogKDFVx6LjS4qXdHha4UlNruS68uWBXEriY o1OcyO9vQ1l5ponwQ/iZH64= X-Google-Smtp-Source: APXvYqyjgzK5zYt1nLkJV1PTASxLCO9v2WEdLQlqLK3u4kKgGoubOcok7hkiDoMtwj/6Q0nO7aqF6A== X-Received: by 2002:adf:8bc5:: with SMTP id w5mr41103202wra.132.1559151809932; Wed, 29 May 2019 10:43:29 -0700 (PDT) Received: from localhost.localdomain ([5.102.238.208]) by smtp.gmail.com with ESMTPSA id k125sm31702wmb.34.2019.05.29.10.43.27 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 29 May 2019 10:43:29 -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 v3 01/13] vfs: introduce generic_copy_file_range() Date: Wed, 29 May 2019 20:43:05 +0300 Message-Id: <20190529174318.22424-2-amir73il@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190529174318.22424-1-amir73il@gmail.com> References: <20190529174318.22424-1-amir73il@gmail.com> Sender: linux-cifs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org 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,