From patchwork Fri Apr 23 13:29:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12220421 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 24D62C43470 for ; Fri, 23 Apr 2021 13:30:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDBA7601FD for ; Fri, 23 Apr 2021 13:30:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242710AbhDWNbB (ORCPT ); Fri, 23 Apr 2021 09:31:01 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:52707 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242886AbhDWNan (ORCPT ); Fri, 23 Apr 2021 09:30:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619184606; 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=Bdwsn4nWLOosF1ZHUuXNAgIl/QXjZ0WtapHyhjaqw78=; b=e2TaW505a5GYqpAi2Xmng8vr/ctIclAoUvGsdREdZdjqHCc4xFk7SyJafCdjVMimBq87J6 /yjbpGvsEG6fkWko8qguO4TZpzUF09G5OiPKondJ3yyvrHfTjFGuPMU4LGR+5cVqOfAbZT n8eUl5xsghF8s160AgZtr/WHzrbYCi4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-585-n4gWwU8oOoqmj7bzFHGoXg-1; Fri, 23 Apr 2021 09:30:05 -0400 X-MC-Unique: n4gWwU8oOoqmj7bzFHGoXg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AD2778026AD; Fri, 23 Apr 2021 13:30:02 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-112-124.rdu2.redhat.com [10.10.112.124]) by smtp.corp.redhat.com (Postfix) with ESMTP id E355150DD2; Fri, 23 Apr 2021 13:29:55 +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 v7 10/31] netfs, mm: Add set/end/wait_on_page_fscache() aliases From: David Howells To: linux-fsdevel@vger.kernel.org Cc: Jeff Layton , Dave Wysochanski , Marc Dionne , Linus Torvalds , Matthew Wilcox , linux-mm@kvack.org, linux-cachefs@redhat.com, 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, dhowells@redhat.com, Trond Myklebust , Anna Schumaker , Steve French , Dominique Martinet , Jeff Layton , David Wysochanski , "Matthew Wilcox (Oracle)" , Alexander Viro , linux-cachefs@redhat.com, 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-kernel@vger.kernel.org, linux-mm@kvack.org Date: Fri, 23 Apr 2021 14:29:55 +0100 Message-ID: <161918459512.3145707.16071556852857197755.stgit@warthog.procyon.org.uk> In-Reply-To: <161918446704.3145707.14418606303992174310.stgit@warthog.procyon.org.uk> References: <161918446704.3145707.14418606303992174310.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Add set/end/wait_on_page_fscache() as aliases of set/end/wait_page_private_2(). These allow a page to marked with PG_fscache, the flag to be removed and waiters woken and waiting for the flag to be cleared. A ref on the page is also taken and dropped. [Linus suggested putting the fscache-themed functions into the caching-specific headers rather than pagemap.h[1]] Changes: v5: - Mirror the changes to the core routines[2]. Signed-off-by: David Howells Tested-by: Jeff Layton Tested-by: Dave Wysochanski Tested-By: Marc Dionne cc: Linus Torvalds cc: Matthew Wilcox cc: linux-mm@kvack.org cc: linux-cachefs@redhat.com cc: linux-afs@lists.infradead.org cc: linux-nfs@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: v9fs-developer@lists.sourceforge.net cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/1330473.1612974547@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/CAHk-=wjgA-74ddehziVk=XAEMTKswPu1Yw4uaro1R3ibs27ztw@mail.gmail.com/ [1] Link: https://lore.kernel.org/r/161340393568.1303470.4997526899111310530.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539536093.286939.5076448803512118764.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/2499407.1616505440@warthog.procyon.org.uk/ [2] Link: https://lore.kernel.org/r/161653793873.2770958.12157243390965814502.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789075327.6155.7432127924219092385.stgit@warthog.procyon.org.uk/ # v6 --- include/linux/netfs.h | 57 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) diff --git a/include/linux/netfs.h b/include/linux/netfs.h index cc1102040488..8479d63406f7 100644 --- a/include/linux/netfs.h +++ b/include/linux/netfs.h @@ -26,4 +26,61 @@ #define TestSetPageFsCache(page) TestSetPagePrivate2((page)) #define TestClearPageFsCache(page) TestClearPagePrivate2((page)) +/** + * set_page_fscache - Set PG_fscache on a page and take a ref + * @page: The page. + * + * Set the PG_fscache (PG_private_2) flag on a page and take the reference + * needed for the VM to handle its lifetime correctly. This sets the flag and + * takes the reference unconditionally, so care must be taken not to set the + * flag again if it's already set. + */ +static inline void set_page_fscache(struct page *page) +{ + set_page_private_2(page); +} + +/** + * end_page_fscache - Clear PG_fscache and release any waiters + * @page: The page + * + * Clear the PG_fscache (PG_private_2) bit on a page and wake up any sleepers + * waiting for this. The page ref held for PG_private_2 being set is released. + * + * This is, for example, used when a netfs page is being written to a local + * disk cache, thereby allowing writes to the cache for the same page to be + * serialised. + */ +static inline void end_page_fscache(struct page *page) +{ + end_page_private_2(page); +} + +/** + * wait_on_page_fscache - Wait for PG_fscache to be cleared on a page + * @page: The page to wait on + * + * Wait for PG_fscache (aka PG_private_2) to be cleared on a page. + */ +static inline void wait_on_page_fscache(struct page *page) +{ + wait_on_page_private_2(page); +} + +/** + * wait_on_page_fscache_killable - Wait for PG_fscache to be cleared on a page + * @page: The page to wait on + * + * Wait for PG_fscache (aka PG_private_2) to be cleared on a page or until a + * fatal signal is received by the calling task. + * + * Return: + * - 0 if successful. + * - -EINTR if a fatal signal was encountered. + */ +static inline int wait_on_page_fscache_killable(struct page *page) +{ + return wait_on_page_private_2_killable(page); +} + #endif /* _LINUX_NETFS_H */