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bh=UYOaJrv+k3qRHTtCyS3jh/xO0Z1XCGBD7xHPEpqnnTw=; b=Pc5CipQnKmUagsl6lG9tJGgx+vp/q3nZWEjzUWnRZbqvIzIjzMU9+Da1yZkWa0+B9l0lS/ HX8vzJDXWYh0/UsGB1IQpEdHVwbVM65WKVS+dHiQgs/bJU28/qVNDcDWa58JbdUrkwZDpn 57BrK+zGRLn3/e0RmJWP5kFjX79sRGY= 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-564-uckJpSsoOA-vkKCPnjkJ1Q-1; Tue, 14 Mar 2023 18:08:13 -0400 X-MC-Unique: uckJpSsoOA-vkKCPnjkJ1Q-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id DDFE73C10C69; Tue, 14 Mar 2023 22:08:12 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 93A36400F4F; Tue, 14 Mar 2023 22:08:10 +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 v18 02/15] splice: Make do_splice_to() generic and export it Date: Tue, 14 Mar 2023 22:07:44 +0000 Message-Id: <20230314220757.3827941-3-dhowells@redhat.com> In-Reply-To: <20230314220757.3827941-1-dhowells@redhat.com> References: <20230314220757.3827941-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-Rspamd-Queue-Id: B0C3F1C0005 X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: iaai8yfo3nctnn664esin3rzwaonn9hb X-HE-Tag: 1678831695-117657 X-HE-Meta: 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 F+GShaPa 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 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 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 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,