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bh=pM2ysDzppt/NTb8ZyH27IEzbM3T0VU0XmStR2DOq6rE=; b=SS7NsFASiIta7fo9ki72BUGPXIlM8RpvEJQsWk5fyELmuhKfz7tR3ipYp8FW0VGEcrGWXt F2+Ex1YwLecY/ID53kxoCuJCZ6okzfrVlbnpdJs+2hRQjZKq9MEA+afIq56TVWj3sIstMR Z/dy6IKe9SOlfiXUBSPfgpmEnvU7eEA= 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-553-qL7E6ESWO2O9-esN8xS6hw-1; Mon, 22 May 2023 09:50:45 -0400 X-MC-Unique: qL7E6ESWO2O9-esN8xS6hw-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 DBA44101AA74; Mon, 22 May 2023 13:50:44 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id 882EE40C6CD8; Mon, 22 May 2023 13:50:41 +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 v22 05/31] splice: Make do_splice_to() generic and export it Date: Mon, 22 May 2023 14:49:52 +0100 Message-Id: <20230522135018.2742245-6-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 X-Rspamd-Queue-Id: B5DC0C0016 X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: rqkgwmsx5ajq7p71x9wrbio4tx5h4wdc X-HE-Tag: 1684763449-795473 X-HE-Meta: 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 5T2JZ6Do dXb8EnyYO87vYvksWz3DUDfy2R26OnEXNsodGJhL9vGu5rPqqcFJ2WX2OOG7IpL5OKnqOkSU7yqyvMl2nb1gxRRfShPgOozU/Eb/PJmFhrf+rSUoN8lrLpF1j3VD3FGhxwDtC0aLCA/DOmWoMS/2rCEV5aQafktBotfZSeswI7oIuD58THkGdeq39+DaktKa6pllnF5Yd2HQJaZpwgVJc6cU2Myth5DALBtQwnFWcMwxkvRBu5wzF58EPYxi+gBDR4qBTAoMqsgqTwtCBxhGvFSGgIvWEaay5oSndhLh0OUsyccz/FYreS0mmT/HkdhkQQbjmXHOYKX0qNbnE98j7D2Mm0BEZfOqx5j64bKzJM7i1RN36LpucmspYomv1Z3ecVTCj09i0J4Xedu7yTLHo4lCcl/m4RCZo2rOmQTUSsms8d2iZrLfJ4ZleIN3FlwjAX+iOCUV7LvuNOL1/ZP9KVQFfIYkHmKGybpPwwvX8jkJmqASVioDDp7yDJw70kUxMq21v X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 Reviewed-by: Christian Brauner 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] --- 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 f9a9be797b0c..d815a69f6589 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -867,12 +867,24 @@ 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; @@ -895,6 +907,7 @@ 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 @@ -964,7 +977,7 @@ 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; @@ -1112,7 +1125,7 @@ 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,