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[2620:137:e000::1:20]) by mx.google.com with ESMTP id j188-20020a6255c5000000b005a8d1616e58si5119433pfb.25.2023.03.15.09.52.52; Wed, 15 Mar 2023 09:53:05 -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=UsJA5sxL; 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 S232298AbjCOQhO (ORCPT + 99 others); Wed, 15 Mar 2023 12:37:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36734 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232204AbjCOQg5 (ORCPT ); Wed, 15 Mar 2023 12:36:57 -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 779646F636 for ; Wed, 15 Mar 2023 09:36:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1678898167; 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=UYOaJrv+k3qRHTtCyS3jh/xO0Z1XCGBD7xHPEpqnnTw=; b=UsJA5sxLYzxWwZSz+4/jCzBhCDS+T0/S1ObJ3n5d1J+135GHMf2aUJE8wPtutUefukkzN7 cvsyqWY6iQsTNKtlYliFfA/X8NJwdJCtKdOt/vnXogMT1TNV5+XyfF/9flHY2pDBtnaocq hDaK6BjOBY7ZYKRD3KncrfMPUPVzdUs= 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-610-HjThJPlUMZe-gype1NTd7Q-1; Wed, 15 Mar 2023 12:36:04 -0400 X-MC-Unique: HjThJPlUMZe-gype1NTd7Q-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E0D933C6675C; Wed, 15 Mar 2023 16:35:58 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 95B66C164E7; Wed, 15 Mar 2023 16:35:56 +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 , Miklos Szeredi , John Hubbard , linux-unionfs@vger.kernel.org Subject: [PATCH v19 02/15] splice: Make do_splice_to() generic and export it Date: Wed, 15 Mar 2023 16:35:36 +0000 Message-Id: <20230315163549.295454-3-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 10.11.54.8 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?1760453391972635799?= X-GMAIL-MSGID: =?utf-8?q?1760453391972635799?= Rename do_splice_to() to vfs_splice_read() and export it so that it can be used as a helper when calling down to a lower layer filesystem as it performs all the necessary checks[1]. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig cc: Miklos Szeredi cc: Jens Axboe cc: Al Viro cc: John Hubbard cc: David Hildenbrand cc: Matthew Wilcox cc: linux-unionfs@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/CAJfpeguGksS3sCigmRi9hJdUec8qtM9f+_9jC1rJhsXT+dV01w@mail.gmail.com/ [1] Reviewed-by: David Hildenbrand --- fs/splice.c | 27 ++++++++++++++++++++------- include/linux/splice.h | 3 +++ 2 files changed, 23 insertions(+), 7 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index abd21a455a2b..90ccd3666dca 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -851,12 +851,24 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out, return out->f_op->splice_write(pipe, out, ppos, len, flags); } -/* - * Attempt to initiate a splice from a file to a pipe. +/** + * vfs_splice_read - Read data from a file and splice it into a pipe + * @in: File to splice from + * @ppos: Input file offset + * @pipe: Pipe to splice to + * @len: Number of bytes to splice + * @flags: Splice modifier flags (SPLICE_F_*) + * + * Splice the requested amount of data from the input file to the pipe. This + * is synchronous as the caller must hold the pipe lock across the entire + * operation. + * + * If successful, it returns the amount of data spliced, 0 if it hit the EOF or + * a hole and a negative error code otherwise. */ -static long do_splice_to(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, size_t len, - unsigned int flags) +long vfs_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags) { unsigned int p_space; int ret; @@ -879,6 +891,7 @@ static long do_splice_to(struct file *in, loff_t *ppos, return warn_unsupported(in, "read"); return in->f_op->splice_read(in, ppos, pipe, len, flags); } +EXPORT_SYMBOL_GPL(vfs_splice_read); /** * splice_direct_to_actor - splices data directly between two non-pipes @@ -949,7 +962,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd, size_t read_len; loff_t pos = sd->pos, prev_pos = pos; - ret = do_splice_to(in, &pos, pipe, len, flags); + ret = vfs_splice_read(in, &pos, pipe, len, flags); if (unlikely(ret <= 0)) goto out_release; @@ -1097,7 +1110,7 @@ long splice_file_to_pipe(struct file *in, pipe_lock(opipe); ret = wait_for_space(opipe, flags); if (!ret) - ret = do_splice_to(in, offset, opipe, len, flags); + ret = vfs_splice_read(in, offset, opipe, len, flags); pipe_unlock(opipe); if (ret > 0) wakeup_pipe_readers(opipe); diff --git a/include/linux/splice.h b/include/linux/splice.h index a55179fd60fc..8f052c3dae95 100644 --- a/include/linux/splice.h +++ b/include/linux/splice.h @@ -76,6 +76,9 @@ extern ssize_t splice_to_pipe(struct pipe_inode_info *, struct splice_pipe_desc *); extern ssize_t add_to_pipe(struct pipe_inode_info *, struct pipe_buffer *); +long vfs_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags); extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *, splice_direct_actor *); extern long do_splice(struct file *in, loff_t *off_in,