From patchwork Fri Oct 22 19:06:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12578797 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CD750C433FE for ; Fri, 22 Oct 2021 19:07:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BB82361038 for ; Fri, 22 Oct 2021 19:07:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234318AbhJVTJp (ORCPT ); Fri, 22 Oct 2021 15:09:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:44446 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234355AbhJVTJ2 (ORCPT ); Fri, 22 Oct 2021 15:09:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634929630; 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=x0vMs89lbKIvv77HDWLfkiKl93g6M7RmmJVwa+wH8Ww=; b=EcmGKRKX/5LdYyv10Zmap7V06cZbZVKVjYNCRuhPE54rPawKkvDQQr64AxX3lgpiuByC/B GT6geu/0RWue9kjsCOoCFrTx4R1FrQ+hWaPGN/ibRDVzc5YCmH6uTaKJTgUEnviej/80IF hXHQ7qe+OGARg+56/O3s5FfYMcsTd/0= 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-355-utPonfrpOiy9HDloa8csrQ-1; Fri, 22 Oct 2021 15:07:04 -0400 X-MC-Unique: utPonfrpOiy9HDloa8csrQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8519418D6A2A; Fri, 22 Oct 2021 19:07:02 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 67F3217CDB; Fri, 22 Oct 2021 19:06:55 +0000 (UTC) Organization: Red Hat UK Ltd. 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Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH v2 34/53] cachefiles: Provide a function to check how much space there is 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: Fri, 22 Oct 2021 20:06:54 +0100 Message-ID: <163492961456.1038219.2922367243827932852.stgit@warthog.procyon.org.uk> In-Reply-To: <163492911924.1038219.13107463173777870713.stgit@warthog.procyon.org.uk> References: <163492911924.1038219.13107463173777870713.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Provide a function to check how much space there is. This also flips the state on the cache and will signal the daemon to inform it of the change and to ask it to do some culling if necessary. Signed-off-by: David Howells cc: linux-cachefs@redhat.com --- fs/cachefiles/Makefile | 1 fs/cachefiles/daemon.c | 108 ++++++++++++++++++++++++++++++++++++++++++++++ fs/cachefiles/internal.h | 15 ++++++ 3 files changed, 124 insertions(+) create mode 100644 fs/cachefiles/daemon.c diff --git a/fs/cachefiles/Makefile b/fs/cachefiles/Makefile index 183fb5f3b8b1..4c80d9af151f 100644 --- a/fs/cachefiles/Makefile +++ b/fs/cachefiles/Makefile @@ -4,6 +4,7 @@ # cachefiles-y := \ + daemon.o \ main.o cachefiles-$(CONFIG_CACHEFILES_ERROR_INJECTION) += error_inject.o diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c new file mode 100644 index 000000000000..dca2520a14ee --- /dev/null +++ b/fs/cachefiles/daemon.c @@ -0,0 +1,108 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Daemon interface + * + * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "internal.h" + +/* + * see if we have space for a number of pages and/or a number of files in the + * cache + */ +int cachefiles_has_space(struct cachefiles_cache *cache, + unsigned fnr, unsigned bnr) +{ + struct kstatfs stats; + int ret; + + struct path path = { + .mnt = cache->mnt, + .dentry = cache->store, + }; + + //_enter("{%llu,%llu,%llu,%llu,%llu,%llu},%u,%u", + // (unsigned long long) cache->frun, + // (unsigned long long) cache->fcull, + // (unsigned long long) cache->fstop, + // (unsigned long long) cache->brun, + // (unsigned long long) cache->bcull, + // (unsigned long long) cache->bstop, + // fnr, bnr); + + /* find out how many pages of blockdev are available */ + memset(&stats, 0, sizeof(stats)); + + ret = vfs_statfs(&path, &stats); + if (ret < 0) { + trace_cachefiles_vfs_error(NULL, d_inode(cache->store), ret, + cachefiles_trace_statfs_error); + if (ret == -EIO) + cachefiles_io_error(cache, "statfs failed"); + _leave(" = %d", ret); + return ret; + } + + stats.f_bavail >>= cache->bshift; + + //_debug("avail %llu,%llu", + // (unsigned long long) stats.f_ffree, + // (unsigned long long) stats.f_bavail); + + /* see if there is sufficient space */ + if (stats.f_ffree > fnr) + stats.f_ffree -= fnr; + else + stats.f_ffree = 0; + + if (stats.f_bavail > bnr) + stats.f_bavail -= bnr; + else + stats.f_bavail = 0; + + ret = -ENOBUFS; + if (stats.f_ffree < cache->fstop || + stats.f_bavail < cache->bstop) + goto begin_cull; + + ret = 0; + if (stats.f_ffree < cache->fcull || + stats.f_bavail < cache->bcull) + goto begin_cull; + + if (test_bit(CACHEFILES_CULLING, &cache->flags) && + stats.f_ffree >= cache->frun && + stats.f_bavail >= cache->brun && + test_and_clear_bit(CACHEFILES_CULLING, &cache->flags) + ) { + _debug("cease culling"); + cachefiles_state_changed(cache); + } + + //_leave(" = 0"); + return 0; + +begin_cull: + if (!test_and_set_bit(CACHEFILES_CULLING, &cache->flags)) { + _debug("### CULL CACHE ###"); + cachefiles_state_changed(cache); + } + + _leave(" = %d", ret); + return ret; +} diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index 230a1a2bf01d..3ccc8411c502 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -114,6 +114,21 @@ struct cachefiles_cache { #include +/* + * note change of state for daemon + */ +static inline void cachefiles_state_changed(struct cachefiles_cache *cache) +{ + set_bit(CACHEFILES_STATE_CHANGED, &cache->flags); + wake_up_all(&cache->daemon_pollwq); +} + +/* + * daemon.c + */ +extern int cachefiles_has_space(struct cachefiles_cache *cache, + unsigned fnr, unsigned bnr); + /* * error_inject.c */