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;
From:   David Howells <dhowells@redhat.com>
To:     Jens Axboe <axboe@kernel.dk>, Al Viro <viro@zeniv.linux.org.uk>,
        Christoph Hellwig <hch@infradead.org>
Cc:     David Howells <dhowells@redhat.com>,
        Matthew Wilcox <willy@infradead.org>, Jan Kara <jack@suse.cz>,
        Jeff Layton <jlayton@kernel.org>,
        David Hildenbrand <david@redhat.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Logan Gunthorpe <logang@deltatee.com>,
        Hillf Danton <hdanton@sina.com>,
        Christian Brauner <brauner@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Christoph Hellwig <hch@lst.de>,
        Mike Marshall <hubcap@omnibond.com>,
        Martin Brandenburg <martin@omnibond.com>,
        devel@lists.orangefs.org
Subject: [PATCH v22 23/31] orangefs: Provide a splice-read wrapper
Date:   Mon, 22 May 2023 14:50:10 +0100
Message-Id: <20230522135018.2742245-24-dhowells@redhat.com>
In-Reply-To: <20230522135018.2742245-1-dhowells@redhat.com>
References: <20230522135018.2742245-1-dhowells@redhat.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Provide a splice_read wrapper for ocfs2.  This increments the read stats
and then locks the inode across the call to filemap_splice_read() and a
revalidation of the mapping.  Splicing from direct I/O is done by the
caller.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Christoph Hellwig <hch@lst.de>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: Jens Axboe <axboe@kernel.dk>
cc: Mike Marshall <hubcap@omnibond.com>
cc: Martin Brandenburg <martin@omnibond.com>
cc: devel@lists.orangefs.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-block@vger.kernel.org
cc: linux-mm@kvack.org
---
 fs/orangefs/file.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/fs/orangefs/file.c b/fs/orangefs/file.c
index 1a4301a38aa7..d68372241b30 100644
--- a/fs/orangefs/file.c
+++ b/fs/orangefs/file.c
@@ -337,6 +337,26 @@ static ssize_t orangefs_file_read_iter(struct kiocb *iocb,
 	return ret;
 }
 
+static ssize_t orangefs_file_splice_read(struct file *in, loff_t *ppos,
+					 struct pipe_inode_info *pipe,
+					 size_t len, unsigned int flags)
+{
+	struct inode *inode = file_inode(in);
+	ssize_t ret;
+
+	orangefs_stats.reads++;
+
+	down_read(&inode->i_rwsem);
+	ret = orangefs_revalidate_mapping(inode);
+	if (ret)
+		goto out;
+
+	ret = filemap_splice_read(in, ppos, pipe, len, flags);
+out:
+	up_read(&inode->i_rwsem);
+	return ret;
+}
+
 static ssize_t orangefs_file_write_iter(struct kiocb *iocb,
     struct iov_iter *iter)
 {
@@ -556,7 +576,7 @@ const struct file_operations orangefs_file_operations = {
 	.lock		= orangefs_lock,
 	.mmap		= orangefs_file_mmap,
 	.open		= generic_file_open,
-	.splice_read    = generic_file_splice_read,
+	.splice_read    = orangefs_file_splice_read,
 	.splice_write   = iter_file_splice_write,
 	.flush		= orangefs_flush,
 	.release	= orangefs_file_release,