From patchwork Fri May 19 07:40:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13247809 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 794FAC7EE2E for ; Fri, 19 May 2023 07:44:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231483AbjESHo0 (ORCPT ); Fri, 19 May 2023 03:44:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231415AbjESHni (ORCPT ); Fri, 19 May 2023 03:43:38 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 012981BC5 for ; Fri, 19 May 2023 00:42:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684482136; 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=gBG1rbAQ+/pvrFxoUU2GMJeglrqrT3cq++hcE5SQo7w=; b=isULdRdZ5A8Vh41OscA8cV8RG+Qah0NQQm4uY37zr+D81Of0I/IEhSS7okoyt8tQ+xDLnt NQV/85LAC5ILAioT8SPnZxNoSVvqPbi1Smh/g2HyFOmiWiUdBz8BUVeR7n4+g/R/34cpLF pKRspjSKKUbPcTxxqbCDyysJygaKurc= 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-465-_MfV9O_bPYGXDbkMXz1GRA-1; Fri, 19 May 2023 03:42:06 -0400 X-MC-Unique: _MfV9O_bPYGXDbkMXz1GRA-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 F0AF585A5BA; Fri, 19 May 2023 07:42:05 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.221]) by smtp.corp.redhat.com (Postfix) with ESMTP id 505E5C0004B; Fri, 19 May 2023 07:42:03 +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 , Mark Fasheh , Joel Becker , Joseph Qi , ocfs2-devel@oss.oracle.com Subject: [PATCH v20 19/32] ocfs2: Provide a splice-read stub Date: Fri, 19 May 2023 08:40:34 +0100 Message-Id: <20230519074047.1739879-20-dhowells@redhat.com> In-Reply-To: <20230519074047.1739879-1-dhowells@redhat.com> References: <20230519074047.1739879-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Provide a splice_read stub for ocfs2. This emits trace lines and does an atime lock/update before calling filemap_splice_read(). It doesn't do this for around direct_splice_read() as that will call ->read_iter(). A couple of new tracepoints are added for this purpose. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Mark Fasheh cc: Joel Becker cc: Joseph Qi cc: ocfs2-devel@oss.oracle.com cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org --- fs/ocfs2/file.c | 42 +++++++++++++++++++++++++++++++++++++++++- fs/ocfs2/ocfs2_trace.h | 3 +++ 2 files changed, 44 insertions(+), 1 deletion(-) diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index efb09de4343d..27c54a71ec57 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2581,6 +2581,46 @@ static ssize_t ocfs2_file_read_iter(struct kiocb *iocb, return ret; } +static ssize_t ocfs2_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 = 0; + int lock_level = 0; + + trace_ocfs2_file_splice_read(inode, in, in->f_path.dentry, + (unsigned long long)OCFS2_I(inode)->ip_blkno, + in->f_path.dentry->d_name.len, + in->f_path.dentry->d_name.name, + 0); + + if (in->f_flags & O_DIRECT) + return direct_splice_read(in, ppos, pipe, len, flags); + + /* + * We're fine letting folks race truncates and extending writes with + * read across the cluster, just like they can locally. Hence no + * rw_lock during read. + * + * Take and drop the meta data lock to update inode fields like i_size. + * This allows the checks down below generic_file_splice_read() a + * chance of actually working. + */ + ret = ocfs2_inode_lock_atime(inode, in->f_path.mnt, &lock_level, true); + if (ret < 0) { + if (ret != -EAGAIN) + mlog_errno(ret); + goto bail; + } + ocfs2_inode_unlock(inode, lock_level); + + ret = filemap_splice_read(in, ppos, pipe, len, flags); + trace_filemap_splice_read_ret(ret); +bail: + return ret; +} + /* Refer generic_file_llseek_unlocked() */ static loff_t ocfs2_file_llseek(struct file *file, loff_t offset, int whence) { @@ -2744,7 +2784,7 @@ const struct file_operations ocfs2_fops = { #endif .lock = ocfs2_lock, .flock = ocfs2_flock, - .splice_read = generic_file_splice_read, + .splice_read = ocfs2_file_splice_read, .splice_write = iter_file_splice_write, .fallocate = ocfs2_fallocate, .remap_file_range = ocfs2_remap_file_range, diff --git a/fs/ocfs2/ocfs2_trace.h b/fs/ocfs2/ocfs2_trace.h index dc4bce1649c1..b8c3d1702076 100644 --- a/fs/ocfs2/ocfs2_trace.h +++ b/fs/ocfs2/ocfs2_trace.h @@ -1319,6 +1319,8 @@ DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_write); DEFINE_OCFS2_FILE_OPS(ocfs2_file_read_iter); +DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_read); + DEFINE_OCFS2_ULL_ULL_ULL_EVENT(ocfs2_truncate_file); DEFINE_OCFS2_ULL_ULL_EVENT(ocfs2_truncate_file_error); @@ -1470,6 +1472,7 @@ TRACE_EVENT(ocfs2_prepare_inode_for_write, ); DEFINE_OCFS2_INT_EVENT(generic_file_read_iter_ret); +DEFINE_OCFS2_INT_EVENT(filemap_splice_read_ret); /* End of trace events for fs/ocfs2/file.c. */