From patchwork Wed Aug 31 02:49:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ronnie Sahlberg X-Patchwork-Id: 12960274 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 924DFECAAD5 for ; Wed, 31 Aug 2022 02:50:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229565AbiHaCuN (ORCPT ); Tue, 30 Aug 2022 22:50:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231161AbiHaCuM (ORCPT ); Tue, 30 Aug 2022 22:50:12 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 63A454D4C6 for ; Tue, 30 Aug 2022 19:50:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1661914210; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jVY2WMjgGK08eQlqeVLw/a2bBJHT8CTVNDR1qNLLd8E=; b=fRY6ylVoCFelj0izi+3K33Q6QtlTPQMIVgHAwvFPK40PZG9yAKXUenZ75JXZzCuArGetF6 0O/fgFQDd3p0viEPhapgcew+FsbRIYaCwOjK5qW8YppO5KJzjKcKyRUTfD3B7REVjhwmPd bBj5GnVa4FuerSGYKxGM4li8xDjbKpo= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-187-cTCq6suPNiSoXs2ylFXhiA-1; Tue, 30 Aug 2022 22:50:07 -0400 X-MC-Unique: cTCq6suPNiSoXs2ylFXhiA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id ECDA51C04B42; Wed, 31 Aug 2022 02:50:06 +0000 (UTC) Received: from localhost.localdomain (vpn2-52-20.bne.redhat.com [10.64.52.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id 29A534010D43; Wed, 31 Aug 2022 02:50:05 +0000 (UTC) From: Ronnie Sahlberg To: linux-cifs Cc: Steve French , Ronnie Sahlberg Subject: [PATCH 6/6] cifs: Add a laundromat thread that will timeout any directory leases we have Date: Wed, 31 Aug 2022 12:49:47 +1000 Message-Id: <20220831024947.3917507-7-lsahlber@redhat.com> In-Reply-To: <20220831024947.3917507-1-lsahlber@redhat.com> References: <20220831024947.3917507-1-lsahlber@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.11.54.2 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org after a timeout of 5 seconds. Later we will add instrumentation to tweak this value. Signed-off-by: Ronnie Sahlberg --- fs/cifs/cached_dir.c | 87 ++++++++++++++++++++++++++++++++++++++------ fs/cifs/cached_dir.h | 1 + 2 files changed, 76 insertions(+), 12 deletions(-) diff --git a/fs/cifs/cached_dir.c b/fs/cifs/cached_dir.c index 20aba23d8d88..16ab0cb9c53c 100644 --- a/fs/cifs/cached_dir.c +++ b/fs/cifs/cached_dir.c @@ -61,17 +61,12 @@ static struct cached_fid *find_or_create_cached_dir(struct cached_fids *cfids, } static struct dentry * -path_to_dentry(struct cifs_sb_info *cifs_sb, const char *full_path) +path_to_dentry(struct cifs_sb_info *cifs_sb, const char *path) { struct dentry *dentry; - char *path = NULL; - char *s, *p; + const char *s, *p; char sep; - path = kstrdup(full_path, GFP_ATOMIC); - if (path == NULL) - return ERR_PTR(-ENOMEM); - sep = CIFS_DIR_SEP(cifs_sb); dentry = dget(cifs_sb->root); s = path; @@ -100,7 +95,7 @@ path_to_dentry(struct cifs_sb_info *cifs_sb, const char *full_path) dput(dentry); dentry = child; } while (!IS_ERR(dentry)); - kfree(path); + return dentry; } @@ -255,15 +250,14 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon, (char *)&cfid->file_all_info)) cfid->file_all_info_is_valid = true; - if (!strlen(path)) { + if (!path[0]) dentry = dget(cifs_sb->root); - cfid->dentry = dentry; - } else{ + else { dentry = path_to_dentry(cifs_sb, path); if (IS_ERR(dentry)) goto oshr_free; - cfid->dentry = dentry; } + cfid->dentry = dentry; cfid->tcon = tcon; cfid->time = jiffies; cfid->is_open = true; @@ -505,6 +499,55 @@ static void free_cached_dir(struct cached_fid *cfid) kfree(cfid); } + + +static int +cifs_cfids_laundromat_thread(void *p) +{ + struct cached_fids *cfids = p; + struct cached_fid *cfid, *q; + struct list_head entry; + + while (!kthread_should_stop()) { + ssleep(1); + INIT_LIST_HEAD(&entry); + if (kthread_should_stop()) + return 0; + spin_lock(&cfids->cfid_list_lock); + list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { + if (jiffies > cfid->time + HZ * 5) { + list_del(&cfid->entry); + list_add(&cfid->entry, &entry); + cfids->num_entries--; + } + } + spin_unlock(&cfids->cfid_list_lock); + + list_for_each_entry_safe(cfid, q, &entry, entry) { + cfid->on_list = false; + list_del(&cfid->entry); + /* + * Cancel, and wait for the work to finish in + * case we are racing with it. + */ + cancel_work_sync(&cfid->lease_break); + if (cfid->has_lease) { + /* + * We lease has not yet been cancelled from + * the server so we need to drop the reference. + */ + spin_lock(&cfids->cfid_list_lock); + cfid->has_lease = false; + spin_unlock(&cfids->cfid_list_lock); + kref_put(&cfid->refcount, smb2_close_cached_fid); + } + } + } + + return 0; +} + + struct cached_fids *init_cached_dirs(void) { struct cached_fids *cfids; @@ -514,6 +557,20 @@ struct cached_fids *init_cached_dirs(void) return NULL; spin_lock_init(&cfids->cfid_list_lock); INIT_LIST_HEAD(&cfids->entries); + + /* + * since we're in a cifs function already, we know that + * this will succeed. No need for try_module_get(). + */ + __module_get(THIS_MODULE); + cfids->laundromat = kthread_run(cifs_cfids_laundromat_thread, + cfids, "cifsd-cfid-laundromat"); + if (IS_ERR(cfids->laundromat)) { + cifs_dbg(VFS, "Failed to start cfids laundromat thread.\n"); + kfree(cfids); + module_put(THIS_MODULE); + return NULL; + } return cfids; } @@ -526,6 +583,12 @@ void free_cached_dirs(struct cached_fids *cfids) struct cached_fid *cfid, *q; struct list_head entry; + if (cfids->laundromat) { + kthread_stop(cfids->laundromat); + cfids->laundromat = NULL; + module_put(THIS_MODULE); + } + INIT_LIST_HEAD(&entry); spin_lock(&cfids->cfid_list_lock); list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { diff --git a/fs/cifs/cached_dir.h b/fs/cifs/cached_dir.h index e536304ca2ce..4ab9b10cd098 100644 --- a/fs/cifs/cached_dir.h +++ b/fs/cifs/cached_dir.h @@ -57,6 +57,7 @@ struct cached_fids { spinlock_t cfid_list_lock; int num_entries; struct list_head entries; + struct task_struct *laundromat; }; extern struct cached_fids *init_cached_dirs(void);