From patchwork Mon Nov 29 14:29:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12644993 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 DB844C4332F for ; Mon, 29 Nov 2021 14:32:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378240AbhK2OgL (ORCPT ); Mon, 29 Nov 2021 09:36:11 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:38986 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378241AbhK2OeH (ORCPT ); Mon, 29 Nov 2021 09:34:07 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1638196249; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jl5Zr3Dm5uNnrFQ85OpZDDY0r4JmMm2VTGR/GEK5Lco=; b=Ecqp8juNqnGWFbO9IfUQfMP73eGfBe0YZTmkw+RSdhbuVEjSz2Q9LnrsL1EhUbbc38odAG G7/DdeYGQBAbmnScCU5tASS+YGbkPG+7OqQ9TxjrmkGGMmGyKiGr7eOCQYYoWAENaXaSa2 DfzvPs0XVjaCOafXGlLtl57SYZh4PgA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-12-A7mscksQMhOPE0KgxEpGOw-1; Mon, 29 Nov 2021 09:30:45 -0500 X-MC-Unique: A7mscksQMhOPE0KgxEpGOw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 322F01015209; Mon, 29 Nov 2021 14:30:13 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.25]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3D99B77E21; Mon, 29 Nov 2021 14:29:32 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 28/64] fscache: Provide a function to note the release of a page From: David Howells To: linux-cachefs@redhat.com Cc: dhowells@redhat.com, Trond Myklebust , Anna Schumaker , Steve French , Dominique Martinet , Jeff Layton , Matthew Wilcox , Alexander Viro , Omar Sandoval , Linus Torvalds , linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs-developer@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 29 Nov 2021 14:29:31 +0000 Message-ID: <163819617128.215744.4725572296135656508.stgit@warthog.procyon.org.uk> In-Reply-To: <163819575444.215744.318477214576928110.stgit@warthog.procyon.org.uk> References: <163819575444.215744.318477214576928110.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Provide a function to be called from a network filesystem's releasepage method to indicate that a page has been released that might have been a reflection of data upon the server - and now that data must be reloaded from the server or the cache. This is used to end an optimisation for empty files, in particular files that have just been created locally, whereby we know there cannot yet be any data that we would need to read from the server or the cache. Signed-off-by: David Howells cc: linux-cachefs@redhat.com --- include/linux/fscache.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/include/linux/fscache.h b/include/linux/fscache.h index 912ed2d7462a..1de789f0dd26 100644 --- a/include/linux/fscache.h +++ b/include/linux/fscache.h @@ -599,4 +599,20 @@ static inline void fscache_clear_inode_writeback(struct fscache_cookie *cookie, } } +/** + * fscache_note_page_release - Note that a netfs page got released + * @cookie: The cookie corresponding to the file + * + * Note that a page that has been copied to the cache has been released. This + * means that future reads will need to look in the cache to see if it's there. + */ +static inline +void fscache_note_page_release(struct fscache_cookie *cookie) +{ + if (cookie && + test_bit(FSCACHE_COOKIE_HAVE_DATA, &cookie->flags) && + test_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags)) + clear_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags); +} + #endif /* _LINUX_FSCACHE_H */