From patchwork Sun May 26 06:10:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amir Goldstein X-Patchwork-Id: 10961389 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 EFC96912 for ; Sun, 26 May 2019 06:11:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E111E28A9B for ; Sun, 26 May 2019 06:11:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D598228AA7; Sun, 26 May 2019 06:11:47 +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 7C88728A9D for ; Sun, 26 May 2019 06:11:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727546AbfEZGLR (ORCPT ); Sun, 26 May 2019 02:11:17 -0400 Received: from mail-wr1-f68.google.com ([209.85.221.68]:40298 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726348AbfEZGLQ (ORCPT ); Sun, 26 May 2019 02:11:16 -0400 Received: by mail-wr1-f68.google.com with SMTP id t4so5380455wrx.7; Sat, 25 May 2019 23:11:14 -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=Klup2ajGNBsp1TUMEpHqQz9uQmHS/z24EFpQImKvOv4=; b=FDeYszfeH4Irc3xuyB+DqAbgZCUORXlYjeZn4d7Y+tjUjlMnUG7XrDqSrTZUrwQYr3 HFXa66Ce9IC0PekcO5UqvVVDiSYzcw2JaEcP94AmPKyBiWGg+t9uwIO3TpXrm9oFIe9y v8MHRb4sPJtNRBC25ZF5LOI0b5yZynVVVbNKG+5mJ2HO0brXaXLAEFWkkA53qSxnxYIU BC6E9EPB9MUz8zYBj71/eHXUsSdbEPXA2VThNzE0n8xlc6kdGXwwYzrzIBrz9A3R2Ee+ AhyNqQV85kboZpQkZ2LL8ZNN4C1I+jmLzc7PrdM/cwmP2Af2CwHmv+UPSJI0oKBjV8KE UrYA== 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=Klup2ajGNBsp1TUMEpHqQz9uQmHS/z24EFpQImKvOv4=; b=pZEhK6GtVmtfeUb7fC153h7kvDi2Fdlmo5Zdufp/RY2Aw/7QUPQ6vrgbDa0YMu5FCQ m4BdxcU69EIkJCzpE0yPfEZMwKK2KNJx+4+jnsvxgPPaDhMqdb30IMg+GimbRSaM0yKH IUyVHZPLbF6e8G0mS4yJp9f1jnXiNpJPjpxk9NX7TK0bQlgCtI+RM9C9ADtvFJQppbf5 kNavz8+JzQ7ay35ISYhvZRE5EINTgNXWc62bOO98/J/JU96O61MwYNqp36YTIUbHaZK7 pdco5737yyOsASSvmoZ2ovmNr77WiEyaYrz1binTM/cOnbRNvCPmxxoJUg6Mon8jG+yQ 7F9g== X-Gm-Message-State: APjAAAUtpSmqqNcCisKuozzQ4w/RIAAhcCYtCnJo2TArHC8FqC7VZD81 sdloiOARDa0W++VJrKD4EJA= X-Google-Smtp-Source: APXvYqyMcIanlzcPtZWca9ywK7oPKEU2lKGbCtF54UJy4mwvocGQBow4pd9xtQeuKSQI2GWlTcH24A== X-Received: by 2002:adf:ed44:: with SMTP id u4mr9097074wro.242.1558851073736; Sat, 25 May 2019 23:11:13 -0700 (PDT) Received: from localhost.localdomain ([5.102.238.208]) by smtp.gmail.com with ESMTPSA id a124sm5302943wmh.3.2019.05.25.23.11.12 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 25 May 2019 23:11:13 -0700 (PDT) From: Amir Goldstein To: "Darrick J . Wong" Cc: Dave Chinner , Christoph Hellwig , Olga Kornievskaia , Luis Henriques , Al Viro , linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, linux-api@vger.kernel.org, Dave Chinner Subject: [PATCH v2 1/8] vfs: introduce generic_copy_file_range() Date: Sun, 26 May 2019 09:10:52 +0300 Message-Id: <20190526061100.21761-2-amir73il@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190526061100.21761-1-amir73il@gmail.com> References: <20190526061100.21761-1-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,