From patchwork Mon May 22 13:49:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13250569 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6B65EC7EE29 for ; Mon, 22 May 2023 13:53:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234203AbjEVNxA (ORCPT ); Mon, 22 May 2023 09:53:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59292 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234033AbjEVNwV (ORCPT ); Mon, 22 May 2023 09:52:21 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE6D5E45 for ; Mon, 22 May 2023 06:50:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684763456; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=NlJ+5nt1dbN0CXPyG6Okiwr3pDsREkSTcJAeP67H8Fs=; b=RqqBj2gHB5aapTzZnlPcmbtJfpejbjHZtER+girFRrO6rOtgO+x1wEWCWnDba+QNcV0mIB A7SYsDvUX0lImM5mNyhW6Nad4EgE5V8E8a03M3qT0OBxjO2DSFHiyFH2wBUtAXyK/3/uO0 P74rxFnEpga5R4xXoZ3qZW5Tbvusio4= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-443-RuncnEKyNrCpayNrIultIA-1; Mon, 22 May 2023 09:50:52 -0400 X-MC-Unique: RuncnEKyNrCpayNrIultIA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 8E38F1C01702; Mon, 22 May 2023 13:50:51 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id E7E3F40C6CD8; Mon, 22 May 2023 13:50:48 +0000 (UTC) From: David Howells To: Jens Axboe , Al Viro , Christoph Hellwig Cc: David Howells , Matthew Wilcox , Jan Kara , Jeff Layton , David Hildenbrand , Jason Gunthorpe , Logan Gunthorpe , Hillf Danton , Christian Brauner , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Christoph Hellwig Subject: [PATCH v22 07/31] splice: Make splice from an O_DIRECT fd use copy_splice_read() Date: Mon, 22 May 2023 14:49:54 +0100 Message-Id: <20230522135018.2742245-8-dhowells@redhat.com> In-Reply-To: <20230522135018.2742245-1-dhowells@redhat.com> References: <20230522135018.2742245-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Make a read splice from a file descriptor that's open O_DIRECT use copy_splice_read() to do the reading as filemap_splice_read() is unlikely to find any pagecache to splice. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Al Viro cc: Jens Axboe cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org --- Notes: ver #21) - Needs to be in vfs_splice_read(), not generic_file_splice_read(). fs/splice.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/splice.c b/fs/splice.c index fe3309ffeb26..76126b1aafcb 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -907,6 +907,12 @@ long vfs_splice_read(struct file *in, loff_t *ppos, if (unlikely(!in->f_op->splice_read)) return warn_unsupported(in, "read"); + /* + * O_DIRECT doesn't deal with the pagecache, so we allocate a buffer, + * copy into it and splice that into the pipe. + */ + if ((in->f_flags & O_DIRECT)) + return copy_splice_read(in, ppos, pipe, len, flags); return in->f_op->splice_read(in, ppos, pipe, len, flags); } EXPORT_SYMBOL_GPL(vfs_splice_read);