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[2620:137:e000::1:20]) by mx.google.com with ESMTP id v12-20020a63d54c000000b0050726756ee8si5578369pgi.93.2023.03.15.09.51.55; Wed, 15 Mar 2023 09:52:09 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=YO9ETLPn; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232524AbjCOQiE (ORCPT + 99 others); Wed, 15 Mar 2023 12:38:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232252AbjCOQh2 (ORCPT ); Wed, 15 Mar 2023 12:37:28 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1B5196C18F for ; Wed, 15 Mar 2023 09:36:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1678898181; 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=tPHDzTeiqkehQq1hzvPvPGknkMXTxgyXWdFbtANbawg=; b=YO9ETLPnnohMqmlfQR79OPpBzZvoSoa5LArSZ9uLU+IGs5JVvsg6/0vMGUu9lpF0lMwK/8 k8pHYzlOTsnhVrFgW3tPnAeMqQHM3tk4wY9MOjzOOnHj9C8yHTPUAGGctyvD0lzMddntvH cY1SHcAudqJL2DFfvhfPqerqRgpdopM= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-84-WUgqb5XdM1OrTaCbnHUsDQ-1; Wed, 15 Mar 2023 12:36:15 -0400 X-MC-Unique: WUgqb5XdM1OrTaCbnHUsDQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id B3540185A78F; Wed, 15 Mar 2023 16:36:14 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 639B01121314; Wed, 15 Mar 2023 16:36:12 +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 , Steve French , John Hubbard , linux-cifs@vger.kernel.org Subject: [PATCH v19 07/15] splice: Do splice read from a file without using ITER_PIPE Date: Wed, 15 Mar 2023 16:35:41 +0000 Message-Id: <20230315163549.295454-8-dhowells@redhat.com> In-Reply-To: <20230315163549.295454-1-dhowells@redhat.com> References: <20230315163549.295454-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1760453333637372219?= X-GMAIL-MSGID: =?utf-8?q?1760453333637372219?= Make generic_file_splice_read() use filemap_splice_read() and direct_splice_read() rather than using an ITER_PIPE and call_read_iter(). With this, ITER_PIPE is no longer used. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig cc: Jens Axboe cc: Steve French cc: Al Viro cc: David Hildenbrand cc: John Hubbard cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christian Brauner --- Notes: ver #18) - Split out the change to cifs to make it use generic_file_splice_read(). - Split out the unexport of filemap_splice_read() (still needed by cifs). fs/splice.c | 30 +++++++----------------------- 1 file changed, 7 insertions(+), 23 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index 90ccd3666dca..f46dd1fb367b 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -387,29 +387,13 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { - struct iov_iter to; - struct kiocb kiocb; - int ret; - - iov_iter_pipe(&to, ITER_DEST, pipe, len); - init_sync_kiocb(&kiocb, in); - kiocb.ki_pos = *ppos; - ret = call_read_iter(in, &kiocb, &to); - if (ret > 0) { - *ppos = kiocb.ki_pos; - file_accessed(in); - } else if (ret < 0) { - /* free what was emitted */ - pipe_discard_from(pipe, to.start_head); - /* - * callers of ->splice_read() expect -EAGAIN on - * "can't put anything in there", rather than -EFAULT. - */ - if (ret == -EFAULT) - ret = -EAGAIN; - } - - return ret; + if (unlikely(*ppos >= file_inode(in)->i_sb->s_maxbytes)) + return 0; + if (unlikely(!len)) + return 0; + if (in->f_flags & O_DIRECT) + return direct_splice_read(in, ppos, pipe, len, flags); + return filemap_splice_read(in, ppos, pipe, len, flags); } EXPORT_SYMBOL(generic_file_splice_read);