From patchwork Fri Nov 20 15:08:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 11920711 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 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 B8EA8C64E7C for ; Fri, 20 Nov 2020 15:09:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6DB042224E for ; Fri, 20 Nov 2020 15:09:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="HQVJsPuW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728569AbgKTPIh (ORCPT ); Fri, 20 Nov 2020 10:08:37 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:23291 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728283AbgKTPIg (ORCPT ); Fri, 20 Nov 2020 10:08:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1605884915; 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=JMNAHTCAjTwh70Q7McXz/EQugFKxJcb35XHm86NOyR0=; b=HQVJsPuWcZNHIFhhY31FtfPz4uQt+dxOs7sih3b7UIArCtYO5al7ArK3g78+pTNPE5gg9N sf6NTPofkFxk8OIZZHELzs6shM7cueoxCxolodO93u0P3pbIn/ZzvgLYLGpNnb649n7zzt 1t+NaMwmn1wId4zZSMUPg+3AHw7zh4Y= 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-249-YBK7ucxvMO2Xq1tUAz8TKw-1; Fri, 20 Nov 2020 10:08:31 -0500 X-MC-Unique: YBK7ucxvMO2Xq1tUAz8TKw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A608018B9F01; Fri, 20 Nov 2020 15:08:29 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-112-246.rdu2.redhat.com [10.10.112.246]) by smtp.corp.redhat.com (Postfix) with ESMTP id 083A55D6AD; Fri, 20 Nov 2020 15:08:23 +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: [RFC PATCH 27/76] fscache: Keep track of size of a file last set independently on the server From: David Howells To: Trond Myklebust , Anna Schumaker , Steve French , Dominique Martinet Cc: dhowells@redhat.com, Jeff Layton , Matthew Wilcox , 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-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Fri, 20 Nov 2020 15:08:23 +0000 Message-ID: <160588490313.3465195.6021579928823503470.stgit@warthog.procyon.org.uk> In-Reply-To: <160588455242.3465195.3214733858273019178.stgit@warthog.procyon.org.uk> References: <160588455242.3465195.3214733858273019178.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org Keep track of the size of a file that we're caching as last set independently on the server by another client. As long as this does not change, we can make the assumption that anything over that boundary, if not represented in the local cache, will not be represented on the server either and can be just cleared rather than being read, thereby saving a trip to the server. This only works if we make space in the cache by zapping whole files and not just punching bits out of them as if we write to the server but don't keep a copy in the cache, the assumption mentioned above no longer holds true. We also need to update this size when invalidation occurs. Signed-off-by: David Howells --- fs/afs/inode.c | 2 +- fs/fscache/cookie.c | 6 +++++- include/linux/fscache.h | 8 +++++--- 3 files changed, 11 insertions(+), 5 deletions(-) diff --git a/fs/afs/inode.c b/fs/afs/inode.c index df999d703e2b..0ba2815f8152 100644 --- a/fs/afs/inode.c +++ b/fs/afs/inode.c @@ -569,7 +569,7 @@ static void afs_zap_data(struct afs_vnode *vnode) _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode); #ifdef CONFIG_AFS_FSCACHE - fscache_invalidate(vnode->cache); + fscache_invalidate(vnode->cache, i_size_read(&vnode->vfs_inode)); #endif /* nuke all the non-dirty pages that aren't locked, mapped or being diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c index e6b87596b1d0..230025a1495c 100644 --- a/fs/fscache/cookie.c +++ b/fs/fscache/cookie.c @@ -159,6 +159,7 @@ struct fscache_cookie *fscache_alloc_cookie( cookie->key_len = index_key_len; cookie->aux_len = aux_data_len; cookie->object_size = object_size; + cookie->zero_point = object_size; strlcpy(cookie->type_name, type_name, sizeof(cookie->type_name)); if (fscache_set_key(cookie, index_key, index_key_len) < 0) @@ -532,7 +533,7 @@ void fscache_set_cookie_stage(struct fscache_cookie *cookie, /* * Invalidate an object. Callable with spinlocks held. */ -void __fscache_invalidate(struct fscache_cookie *cookie) +void __fscache_invalidate(struct fscache_cookie *cookie, loff_t new_size) { struct fscache_object *object = NULL; @@ -548,6 +549,9 @@ void __fscache_invalidate(struct fscache_cookie *cookie) ASSERTCMP(cookie->type, ==, FSCACHE_COOKIE_TYPE_DATAFILE); spin_lock(&cookie->lock); + cookie->object_size = new_size; + cookie->zero_point = new_size; + if (!hlist_empty(&cookie->backing_objects)) object = hlist_entry(cookie->backing_objects.first, struct fscache_object, cookie_link); diff --git a/include/linux/fscache.h b/include/linux/fscache.h index 3cd18ddc3903..8d47c7a08456 100644 --- a/include/linux/fscache.h +++ b/include/linux/fscache.h @@ -118,6 +118,7 @@ struct fscache_cookie { struct list_head proc_link; /* Link in proc list */ char type_name[8]; /* Cookie type name */ loff_t object_size; /* Size of the netfs object */ + loff_t zero_point; /* Size after which no data on server */ unsigned long flags; #define FSCACHE_COOKIE_RELINQUISHED 6 /* T if cookie has been relinquished */ @@ -201,7 +202,7 @@ extern int __fscache_begin_operation(struct fscache_cookie *, struct fscache_op_ enum fscache_want_stage); extern void __fscache_relinquish_cookie(struct fscache_cookie *, bool); extern void __fscache_update_cookie(struct fscache_cookie *, const void *, const loff_t *); -extern void __fscache_invalidate(struct fscache_cookie *); +extern void __fscache_invalidate(struct fscache_cookie *, loff_t); /** * fscache_register_netfs - Register a filesystem as desiring caching services @@ -427,6 +428,7 @@ void fscache_unpin_cookie(struct fscache_cookie *cookie) /** * fscache_invalidate - Notify cache that an object needs invalidation * @cookie: The cookie representing the cache object + * @size: The revised size of the object. * * Notify the cache that an object is needs to be invalidated and that it * should abort any retrievals or stores it is doing on the cache. The object @@ -438,10 +440,10 @@ void fscache_unpin_cookie(struct fscache_cookie *cookie) * description. */ static inline -void fscache_invalidate(struct fscache_cookie *cookie) +void fscache_invalidate(struct fscache_cookie *cookie, loff_t size) { if (fscache_cookie_valid(cookie)) - __fscache_invalidate(cookie); + __fscache_invalidate(cookie, size); } /**