From mboxrd@z Thu Jan 1 00:00:00 1970 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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BEB0EC433F5 for ; Mon, 27 Dec 2021 12:55:46 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4JMyMP2T5Kz302G for ; Mon, 27 Dec 2021 23:55:45 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.131; helo=out30-131.freemail.mail.aliyun.com; envelope-from=jefflexu@linux.alibaba.com; receiver=) Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com [115.124.30.131]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4JMyMG3cNhz30RS for ; Mon, 27 Dec 2021 23:55:37 +1100 (AEDT) X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R161e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=e01e04400; MF=jefflexu@linux.alibaba.com; NM=1; PH=DS; RN=12; SR=0; TI=SMTPD_---0V.xJoPB_1640609686; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0V.xJoPB_1640609686) by smtp.aliyun-inc.com(127.0.0.1); Mon, 27 Dec 2021 20:54:47 +0800 From: Jeffle Xu To: dhowells@redhat.com, linux-cachefs@redhat.com, xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Subject: [PATCH v1 02/23] cachefiles: add mode command to distinguish modes Date: Mon, 27 Dec 2021 20:54:23 +0800 Message-Id: <20211227125444.21187-3-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20211227125444.21187-1-jefflexu@linux.alibaba.com> References: <20211227125444.21187-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: tao.peng@linux.alibaba.com, linux-kernel@vger.kernel.org, joseph.qi@linux.alibaba.com, bo.liu@linux.alibaba.com, linux-fsdevel@vger.kernel.org, eguan@linux.alibaba.com, gerry@linux.alibaba.com Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" Add one flag bit to distinguish the new introduced demand-read mode from the original mode. User daemon could set the specified mode with 'mode' command. If user daemon doesn't ever explicitly set the mode, then the behaviour is the same with that prior this patch, i.e. cachefiles serves as the local cache for remote fs by default. Signed-off-by: Jeffle Xu --- fs/cachefiles/daemon.c | 32 ++++++++++++++++++++++++++++++++ fs/cachefiles/internal.h | 1 + 2 files changed, 33 insertions(+) diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index 871f1e0f423d..892a9bdba53f 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -41,6 +41,7 @@ static int cachefiles_daemon_dir(struct cachefiles_cache *, char *); static int cachefiles_daemon_inuse(struct cachefiles_cache *, char *); static int cachefiles_daemon_secctx(struct cachefiles_cache *, char *); static int cachefiles_daemon_tag(struct cachefiles_cache *, char *); +static int cachefiles_daemon_mode(struct cachefiles_cache *, char *); static int cachefiles_daemon_bind(struct cachefiles_cache *, char *); static void cachefiles_daemon_unbind(struct cachefiles_cache *); @@ -83,6 +84,7 @@ static const struct cachefiles_daemon_cmd cachefiles_daemon_cmds[] = { { "inuse", cachefiles_daemon_inuse }, { "secctx", cachefiles_daemon_secctx }, { "tag", cachefiles_daemon_tag }, + { "mode", cachefiles_daemon_mode }, { "", NULL } }; @@ -671,6 +673,36 @@ static int cachefiles_daemon_inuse(struct cachefiles_cache *cache, char *args) return -EINVAL; } +/* + * Set the cache mode + * - command: "mode cache|demand" + */ +static int cachefiles_daemon_mode(struct cachefiles_cache *cache, char *args) +{ + _enter(",%s", args); + + if (test_bit(CACHEFILES_READY, &cache->flags)) { + pr_err("Cache already started\n"); + return -EINVAL; + } + + if (!*args) { + pr_err("Empty mode specified\n"); + return -EINVAL; + } + + if (!strncmp(args, "cache", strlen("cache"))) { + clear_bit(CACHEFILES_DEMAND_MODE, &cache->flags); + } else if (!strncmp(args, "demand", strlen("demand"))) { + set_bit(CACHEFILES_DEMAND_MODE, &cache->flags); + } else { + pr_err("Invalid mode specified\n"); + return -EINVAL; + } + + return 0; +} + /* * Bind a directory as a cache */ diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index e0ed811d628d..a8e6500889d7 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -98,6 +98,7 @@ struct cachefiles_cache { #define CACHEFILES_DEAD 1 /* T if cache dead */ #define CACHEFILES_CULLING 2 /* T if cull engaged */ #define CACHEFILES_STATE_CHANGED 3 /* T if state changed (poll trigger) */ +#define CACHEFILES_DEMAND_MODE 4 /* T if works in demand read mode for read-only fs */ char *rootdirname; /* name of cache root directory */ char *secctx; /* LSM security context */ char *tag; /* cache binding tag */ -- 2.27.0