From patchwork Mon Jan 10 18:50:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dai Ngo X-Patchwork-Id: 12709058 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 7B108C4332F for ; Mon, 10 Jan 2022 18:51:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242458AbiAJSvX (ORCPT ); Mon, 10 Jan 2022 13:51:23 -0500 Received: from mx0a-00069f02.pphosted.com ([205.220.165.32]:46964 "EHLO mx0a-00069f02.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242474AbiAJSvS (ORCPT ); Mon, 10 Jan 2022 13:51:18 -0500 Received: from pps.filterd (m0246629.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 20AIlSlP001336; Mon, 10 Jan 2022 18:51:13 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2021-07-09; bh=DweiOUgl/hkOGesDpgQ+/pDf8TBMxj3hc8JKRsSd/zQ=; b=PYz25vHQtr1wUhW3jZFPbEylPBjvYB4SXCZwL9XOQyq8oB5brTo+6J4sVpw+VlbpD4Xu WkPaW5ecTpkNAcsRoKi90r6FIQDKIOvPs4A3xsCUfGLQW+PuA/cdQLGo50+QRCVIaJla dnCp/x/Pqd2V5QeDuWqcnvSvn1LSycdfFTH4nXBa3WMU0uZHGaw3qevzGmKSExuINJot HvhKIvgyA4vkKA7e+amc2nORozfTLs4rpRt1KNrDyzpYioeT7Q2YZxhBSSdUvh0O9/bC iOFKBXp6rC6n7GEACy22kNk2a3dYfxcEHlOwky7YHfWBcj1Xi7UMPg24WwBBXPyPZAhk nA== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by mx0b-00069f02.pphosted.com with ESMTP id 3dgn748y9f-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 10 Jan 2022 18:51:13 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.1.2/8.16.1.2) with SMTP id 20AIk7Br115835; Mon, 10 Jan 2022 18:51:12 GMT Received: from pps.reinject (localhost [127.0.0.1]) by userp3030.oracle.com with ESMTP id 3deyqvubdn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 10 Jan 2022 18:51:12 +0000 Received: from userp3030.oracle.com (userp3030.oracle.com [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 20AIpBum140178; Mon, 10 Jan 2022 18:51:11 GMT Received: from ca-common-hq.us.oracle.com (ca-common-hq.us.oracle.com [10.211.9.209]) by userp3030.oracle.com with ESMTP id 3deyqvubcm-2; Mon, 10 Jan 2022 18:51:11 +0000 From: Dai Ngo To: bfields@fieldses.org, chuck.lever@oracle.com Cc: jlayton@redhat.com, viro@zeniv.linux.org.uk, linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH RFC v9 1/2] fs/lock: add new callback, lm_expire_lock, to lock_manager_operations Date: Mon, 10 Jan 2022 10:50:52 -0800 Message-Id: <1641840653-23059-2-git-send-email-dai.ngo@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1641840653-23059-1-git-send-email-dai.ngo@oracle.com> References: <1641840653-23059-1-git-send-email-dai.ngo@oracle.com> X-Proofpoint-ORIG-GUID: sD_JpfSElReBvfXbf17yIVY4irReKXMW X-Proofpoint-GUID: sD_JpfSElReBvfXbf17yIVY4irReKXMW Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Add new callback, lm_expire_lock, to lock_manager_operations to allow the lock manager to take appropriate action to resolve the lock conflict if possible. The callback takes 1 argument, the file_lock of the blocker and returns true if the conflict was resolved else returns false. Note that the lock manager has to be able to resolve the conflict while the spinlock flc_lock is held. Lock manager, such as NFSv4 courteous server, uses this callback to resolve conflict by destroying lock owner, or the NFSv4 courtesy client (client that has expired but allowed to maintains its states) that owns the lock. Signed-off-by: Dai Ngo --- fs/locks.c | 14 ++++++++++---- include/linux/fs.h | 1 + 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index 3d6fb4ae847b..5844fd29560d 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -963,10 +963,13 @@ posix_test_lock(struct file *filp, struct file_lock *fl) spin_lock(&ctx->flc_lock); list_for_each_entry(cfl, &ctx->flc_posix, fl_list) { - if (posix_locks_conflict(fl, cfl)) { - locks_copy_conflock(fl, cfl); - goto out; - } + if (!posix_locks_conflict(fl, cfl)) + continue; + if (cfl->fl_lmops && cfl->fl_lmops->lm_expire_lock && + cfl->fl_lmops->lm_expire_lock(cfl)) + continue; + locks_copy_conflock(fl, cfl); + goto out; } fl->fl_type = F_UNLCK; out: @@ -1169,6 +1172,9 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request, list_for_each_entry(fl, &ctx->flc_posix, fl_list) { if (!posix_locks_conflict(request, fl)) continue; + if (fl->fl_lmops && fl->fl_lmops->lm_expire_lock && + fl->fl_lmops->lm_expire_lock(fl)) + continue; if (conflock) locks_copy_conflock(conflock, fl); error = -EAGAIN; diff --git a/include/linux/fs.h b/include/linux/fs.h index e7a633353fd2..0f70e0b39834 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1071,6 +1071,7 @@ struct lock_manager_operations { int (*lm_change)(struct file_lock *, int, struct list_head *); void (*lm_setup)(struct file_lock *, void **); bool (*lm_breaker_owns_lease)(struct file_lock *); + bool (*lm_expire_lock)(struct file_lock *cfl); }; struct lock_manager {