From patchwork Fri Jan 28 19:39:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dai Ngo X-Patchwork-Id: 12728990 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 793B4C4332F for ; Fri, 28 Jan 2022 19:40:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344235AbiA1TkB (ORCPT ); Fri, 28 Jan 2022 14:40:01 -0500 Received: from mx0a-00069f02.pphosted.com ([205.220.165.32]:30290 "EHLO mx0a-00069f02.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344147AbiA1TkA (ORCPT ); Fri, 28 Jan 2022 14:40:00 -0500 Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 20SIi0ff032646; Fri, 28 Jan 2022 19:39:57 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=2sS1wkdpPi8hqyth/o0IYJ7+3AIJhshz50LoLfajj5M=; b=EcRnbqB0So7dMfC8fE5yzsqTqbgfV14XOUKWedcrRx23ADBKjAABdXE5vtpbMwuuhFby rvn5TBOJt6g3CXTXJwrHr2Qkm7ADhTlegAWYQi5F6YbKBMjJVfwhjkKc+B2hBF8K912e jyMzUfNcIwXkrbUAljWyN1LxS1VVuuVToK8IDZyrL25LFWkI9/+RSWI39TR/zg35ThFr Xm0ue/JeWHAZnKPHKKdjrEzAqJ8wD+aNUOxaARLyp09837q3VRiA3EsXs7gnMf36klGU QN0ZKQ+xqa5qtodzzRgWax0mX4HE5BMvovXEl4SMzNJIRkj1mDucjfGsKgGqWtVjw45n oQ== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by mx0b-00069f02.pphosted.com with ESMTP id 3duwrxmaqy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 Jan 2022 19:39:57 +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 20SJR9jO192126; Fri, 28 Jan 2022 19:39:55 GMT Received: from pps.reinject (localhost [127.0.0.1]) by userp3030.oracle.com with ESMTP id 3dr726eqwn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 Jan 2022 19:39:55 +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 20SJdsjM038315; Fri, 28 Jan 2022 19:39:55 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 3dr726eqv5-2; Fri, 28 Jan 2022 19:39:55 +0000 From: Dai Ngo To: chuck.lever@oracle.com, bfields@fieldses.org Cc: jlayton@redhat.com, viro@zeniv.linux.org.uk, linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH RFC 1/3] fs/lock: add new callback, lm_expire_lock, to lock_manager_operations Date: Fri, 28 Jan 2022 11:39:31 -0800 Message-Id: <1643398773-29149-2-git-send-email-dai.ngo@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1643398773-29149-1-git-send-email-dai.ngo@oracle.com> References: <1643398773-29149-1-git-send-email-dai.ngo@oracle.com> X-Proofpoint-GUID: 018YHAd9NSw6lKZAvwOhgyeXmG5ENiHG X-Proofpoint-ORIG-GUID: 018YHAd9NSw6lKZAvwOhgyeXmG5ENiHG Precedence: bulk List-ID: X-Mailing-List: linux-nfs@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 Acked-by: Jeff Layton --- Documentation/filesystems/locking.rst | 2 ++ fs/locks.c | 14 ++++++++++---- include/linux/fs.h | 1 + 3 files changed, 13 insertions(+), 4 deletions(-) diff --git a/Documentation/filesystems/locking.rst b/Documentation/filesystems/locking.rst index d36fe79167b3..57ce0fbc8ab1 100644 --- a/Documentation/filesystems/locking.rst +++ b/Documentation/filesystems/locking.rst @@ -439,6 +439,7 @@ prototypes:: void (*lm_break)(struct file_lock *); /* break_lease callback */ int (*lm_change)(struct file_lock **, int); bool (*lm_breaker_owns_lease)(struct file_lock *); + bool (*lm_lock_conflict)(struct file_lock *); locking rules: @@ -450,6 +451,7 @@ lm_grant: no no no lm_break: yes no no lm_change yes no no lm_breaker_owns_lease: no no no +lm_lock_conflict: no no no ====================== ============= ================= ========= buffer_head diff --git a/fs/locks.c b/fs/locks.c index 0fca9d680978..052b42cc7f25 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -853,10 +853,13 @@ 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_lock_conflict && + !cfl->fl_lmops->lm_lock_conflict(cfl)) + continue; + locks_copy_conflock(fl, cfl); + goto out; } fl->fl_type = F_UNLCK; out: @@ -1059,6 +1062,9 @@ 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_lock_conflict && + !fl->fl_lmops->lm_lock_conflict(fl)) + continue; if (conflock) locks_copy_conflock(conflock, fl); error = -EAGAIN; diff --git a/include/linux/fs.h b/include/linux/fs.h index bbf812ce89a8..21cb7afe2d63 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1068,6 +1068,7 @@ 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_lock_conflict)(struct file_lock *cfl); }; struct lock_manager { From patchwork Fri Jan 28 19:39:32 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dai Ngo X-Patchwork-Id: 12728989 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 1E101C433F5 for ; Fri, 28 Jan 2022 19:40:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344229AbiA1TkB (ORCPT ); Fri, 28 Jan 2022 14:40:01 -0500 Received: from mx0a-00069f02.pphosted.com ([205.220.165.32]:29864 "EHLO mx0a-00069f02.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241858AbiA1TkA (ORCPT ); Fri, 28 Jan 2022 14:40:00 -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 20SJ2i5p019366; 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Fri, 28 Jan 2022 19:39:56 +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 20SJdsjO038315; Fri, 28 Jan 2022 19:39:55 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 3dr726eqv5-3; Fri, 28 Jan 2022 19:39:55 +0000 From: Dai Ngo To: chuck.lever@oracle.com, bfields@fieldses.org Cc: jlayton@redhat.com, viro@zeniv.linux.org.uk, linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH RFC 2/3] fs/lock: only call lm_breaker_owns_lease if there is conflict. Date: Fri, 28 Jan 2022 11:39:32 -0800 Message-Id: <1643398773-29149-3-git-send-email-dai.ngo@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1643398773-29149-1-git-send-email-dai.ngo@oracle.com> References: <1643398773-29149-1-git-send-email-dai.ngo@oracle.com> X-Proofpoint-GUID: d9hHfsj75U2YCzCov2wt9gD9OmAWgIsW X-Proofpoint-ORIG-GUID: d9hHfsj75U2YCzCov2wt9gD9OmAWgIsW Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Modify leases_conflict to call lm_breaker_owns_lease only if there is real conflict. This is to allow the lock manager to resolve the conflict if possible. Signed-off-by: Dai Ngo Acked-by: Jeff Layton --- fs/locks.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index 052b42cc7f25..456717873cff 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1357,9 +1357,6 @@ static bool leases_conflict(struct file_lock *lease, struct file_lock *breaker) { bool rc; - if (lease->fl_lmops->lm_breaker_owns_lease - && lease->fl_lmops->lm_breaker_owns_lease(lease)) - return false; if ((breaker->fl_flags & FL_LAYOUT) != (lease->fl_flags & FL_LAYOUT)) { rc = false; goto trace; @@ -1370,6 +1367,9 @@ static bool leases_conflict(struct file_lock *lease, struct file_lock *breaker) } rc = locks_conflict(breaker, lease); + if (rc && lease->fl_lmops->lm_breaker_owns_lease && + lease->fl_lmops->lm_breaker_owns_lease(lease)) + rc = false; trace: trace_leases_conflict(rc, lease, breaker); return rc; From patchwork Fri Jan 28 19:39:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dai Ngo X-Patchwork-Id: 12728991 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 EF8F0C43217 for ; Fri, 28 Jan 2022 19:40:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241858AbiA1TkC (ORCPT ); Fri, 28 Jan 2022 14:40:02 -0500 Received: from mx0a-00069f02.pphosted.com ([205.220.165.32]:31762 "EHLO mx0a-00069f02.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232304AbiA1TkB (ORCPT ); Fri, 28 Jan 2022 14:40:01 -0500 Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 20SIacwq032625; Fri, 28 Jan 2022 19:39:58 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=1JGJ4iFQOXtOw9VMTAO0bZ/ZY1/MORzy1q25oNyUk/8=; b=dov4NGzhjBrRFWjkyNq/Q0Y65efQPJKUOIRBf+hqD/7A4pgWeTYAMrbOMI3cB46Xi38B 5eaO5sHCTV6zEaK/2argSsN9939dgj81iqoeh3Q9oW2MBG+LJK+bDlZjjeFpwxxXMHTi o4oiF7NQGfWchU//kex0VuVS/7/dwY3B6S6bCysmT2iEpx2nEXb84u1/UXe6xhm0N/yb hEdU4qF7H76cxIaHXiCwGTx41bxZ1tJpTcyo2D7GXGnQH1tpTd0vX0CXUEmV89QrWULl DJVGUMHqWAMPTNcsVL0BaDkpFFtw01tR0J9+DmnnnnCdHHIOfXXpHgixN+ueiG49dk33 Rw== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by mx0b-00069f02.pphosted.com with ESMTP id 3duwrxmar2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 Jan 2022 19:39:58 +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 20SJRASD192177; Fri, 28 Jan 2022 19:39:56 GMT Received: from pps.reinject (localhost [127.0.0.1]) by userp3030.oracle.com with ESMTP id 3dr726eqy0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 Jan 2022 19:39:56 +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 20SJdsjQ038315; Fri, 28 Jan 2022 19:39:56 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 3dr726eqv5-4; Fri, 28 Jan 2022 19:39:56 +0000 From: Dai Ngo To: chuck.lever@oracle.com, bfields@fieldses.org Cc: jlayton@redhat.com, viro@zeniv.linux.org.uk, linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH RFC 3/3] nfsd: Initial implementation of NFSv4 Courteous Server Date: Fri, 28 Jan 2022 11:39:33 -0800 Message-Id: <1643398773-29149-4-git-send-email-dai.ngo@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1643398773-29149-1-git-send-email-dai.ngo@oracle.com> References: <1643398773-29149-1-git-send-email-dai.ngo@oracle.com> X-Proofpoint-GUID: S7w9nZQdvHjxpiWp4W6amzUe45NCXOzt X-Proofpoint-ORIG-GUID: S7w9nZQdvHjxpiWp4W6amzUe45NCXOzt Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Currently an NFSv4 client must maintain its lease by using the at least one of the state tokens or if nothing else, by issuing a RENEW (4.0), or a singleton SEQUENCE (4.1) at least once during each lease period. If the client fails to renew the lease, for any reason, the Linux server expunges the state tokens immediately upon detection of the "failure to renew the lease" condition and begins returning NFS4ERR_EXPIRED if the client should reconnect and attempt to use the (now) expired state. The default lease period for the Linux server is 90 seconds. The typical client cuts that in half and will issue a lease renewing operation every 45 seconds. The 90 second lease period is very short considering the potential for moderately long term network partitions. A network partition refers to any loss of network connectivity between the NFS client and the NFS server, regardless of its root cause. This includes NIC failures, NIC driver bugs, network misconfigurations & administrative errors, routers & switches crashing and/or having software updates applied, even down to cables being physically pulled. In most cases, these network failures are transient, although the duration is unknown. A server which does not immediately expunge the state on lease expiration is known as a Courteous Server. A Courteous Server continues to recognize previously generated state tokens as valid until conflict arises between the expired state and the requests from another client, or the server reboots. The initial implementation of the Courteous Server will do the following: . When the laundromat thread detects an expired client and if that client still has established state on the Linux server and there is no waiters for the client's locks then deletes the client persistent record and marks the client as COURTESY_CLIENT and skips destroying the client and all of state, otherwise destroys the client as usual. . Client persistent record is added to the client database when the courtesy client reconnects and transits to normal client. . Lock/delegation/share reversation conflict with courtesy client is resolved by marking the courtesy client as DESTROY_COURTESY_CLIENT, effectively disable it, then allow the current request to proceed immediately. . Courtesy client marked as DESTROY_COURTESY_CLIENT is not allowed to reconnect to reuse itsstate. It is expired by the laundromat asynchronously in the background. Signed-off-by: Dai Ngo --- fs/nfsd/nfs4state.c | 454 +++++++++++++++++++++++++++++++++++++++++++++++----- fs/nfsd/state.h | 5 + 2 files changed, 415 insertions(+), 44 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 1956d377d1a6..b302d857e196 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -125,6 +125,8 @@ static void free_session(struct nfsd4_session *); static const struct nfsd4_callback_ops nfsd4_cb_recall_ops; static const struct nfsd4_callback_ops nfsd4_cb_notify_lock_ops; +static const int courtesy_client_expiry = (24 * 60 * 60); /* in secs */ + static bool is_session_dead(struct nfsd4_session *ses) { return ses->se_flags & NFS4_SESSION_DEAD; @@ -1913,14 +1915,37 @@ __find_in_sessionid_hashtbl(struct nfs4_sessionid *sessionid, struct net *net) static struct nfsd4_session * find_in_sessionid_hashtbl(struct nfs4_sessionid *sessionid, struct net *net, - __be32 *ret) + __be32 *ret, bool *courtesy_clnt) { struct nfsd4_session *session; __be32 status = nfserr_badsession; + struct nfs4_client *clp; session = __find_in_sessionid_hashtbl(sessionid, net); if (!session) goto out; + clp = session->se_client; + if (courtesy_clnt) + *courtesy_clnt = false; + if (clp) { + /* need to sync with thread resolving lock/deleg conflict */ + spin_lock(&clp->cl_cs_lock); + if (test_bit(NFSD4_DESTROY_COURTESY_CLIENT, &clp->cl_flags)) { + spin_unlock(&clp->cl_cs_lock); + session = NULL; + goto out; + } + if (test_bit(NFSD4_COURTESY_CLIENT, &clp->cl_flags)) { + if (!courtesy_clnt) { + spin_unlock(&clp->cl_cs_lock); + session = NULL; + goto out; + } + clear_bit(NFSD4_COURTESY_CLIENT, &clp->cl_flags); + *courtesy_clnt = true; + } + spin_unlock(&clp->cl_cs_lock); + } status = nfsd4_get_session_locked(session); if (status) session = NULL; @@ -1990,6 +2015,7 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) INIT_LIST_HEAD(&clp->cl_openowners); INIT_LIST_HEAD(&clp->cl_delegations); INIT_LIST_HEAD(&clp->cl_lru); + INIT_LIST_HEAD(&clp->cl_cs_list); INIT_LIST_HEAD(&clp->cl_revoked); #ifdef CONFIG_NFSD_PNFS INIT_LIST_HEAD(&clp->cl_lo_states); @@ -1997,6 +2023,7 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name) INIT_LIST_HEAD(&clp->async_copies); spin_lock_init(&clp->async_lock); spin_lock_init(&clp->cl_lock); + spin_lock_init(&clp->cl_cs_lock); rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table"); return clp; err_no_hashtbl: @@ -2394,6 +2421,10 @@ static int client_info_show(struct seq_file *m, void *v) seq_puts(m, "status: confirmed\n"); else seq_puts(m, "status: unconfirmed\n"); + seq_printf(m, "courtesy client: %s\n", + test_bit(NFSD4_COURTESY_CLIENT, &clp->cl_flags) ? "yes" : "no"); + seq_printf(m, "seconds from last renew: %lld\n", + ktime_get_boottime_seconds() - clp->cl_time); seq_printf(m, "name: "); seq_quote_mem(m, clp->cl_name.data, clp->cl_name.len); seq_printf(m, "\nminor version: %d\n", clp->cl_minorversion); @@ -2801,12 +2832,15 @@ add_clp_to_name_tree(struct nfs4_client *new_clp, struct rb_root *root) } static struct nfs4_client * -find_clp_in_name_tree(struct xdr_netobj *name, struct rb_root *root) +find_clp_in_name_tree(struct xdr_netobj *name, struct rb_root *root, + bool *courtesy_client) { int cmp; struct rb_node *node = root->rb_node; struct nfs4_client *clp; + if (courtesy_client) + *courtesy_client = false; while (node) { clp = rb_entry(node, struct nfs4_client, cl_namenode); cmp = compare_blob(&clp->cl_name, name); @@ -2814,8 +2848,29 @@ find_clp_in_name_tree(struct xdr_netobj *name, struct rb_root *root) node = node->rb_left; else if (cmp < 0) node = node->rb_right; - else + else { + /* sync with thread resolving lock/deleg conflict */ + spin_lock(&clp->cl_cs_lock); + if (test_bit(NFSD4_DESTROY_COURTESY_CLIENT, + &clp->cl_flags)) { + spin_unlock(&clp->cl_cs_lock); + return NULL; + } + if (test_bit(NFSD4_COURTESY_CLIENT, + &clp->cl_flags)) { + if (!courtesy_client) { + set_bit(NFSD4_DESTROY_COURTESY_CLIENT, + &clp->cl_flags); + spin_unlock(&clp->cl_cs_lock); + return NULL; + } + clear_bit(NFSD4_COURTESY_CLIENT, + &clp->cl_flags); + *courtesy_client = true; + } + spin_unlock(&clp->cl_cs_lock); return clp; + } } return NULL; } @@ -2852,15 +2907,38 @@ move_to_confirmed(struct nfs4_client *clp) } static struct nfs4_client * -find_client_in_id_table(struct list_head *tbl, clientid_t *clid, bool sessions) +find_client_in_id_table(struct list_head *tbl, clientid_t *clid, bool sessions, + bool *courtesy_clnt) { struct nfs4_client *clp; unsigned int idhashval = clientid_hashval(clid->cl_id); + if (courtesy_clnt) + *courtesy_clnt = false; list_for_each_entry(clp, &tbl[idhashval], cl_idhash) { if (same_clid(&clp->cl_clientid, clid)) { if ((bool)clp->cl_minorversion != sessions) return NULL; + + /* need to sync with thread resolving lock/deleg conflict */ + spin_lock(&clp->cl_cs_lock); + if (test_bit(NFSD4_DESTROY_COURTESY_CLIENT, + &clp->cl_flags)) { + spin_unlock(&clp->cl_cs_lock); + continue; + } + if (test_bit(NFSD4_COURTESY_CLIENT, &clp->cl_flags)) { + if (!courtesy_clnt) { + set_bit(NFSD4_DESTROY_COURTESY_CLIENT, + &clp->cl_flags); + spin_unlock(&clp->cl_cs_lock); + continue; + } + clear_bit(NFSD4_COURTESY_CLIENT, + &clp->cl_flags); + *courtesy_clnt = true; + } + spin_unlock(&clp->cl_cs_lock); renew_client_locked(clp); return clp; } @@ -2869,12 +2947,13 @@ find_client_in_id_table(struct list_head *tbl, clientid_t *clid, bool sessions) } static struct nfs4_client * -find_confirmed_client(clientid_t *clid, bool sessions, struct nfsd_net *nn) +find_confirmed_client(clientid_t *clid, bool sessions, struct nfsd_net *nn, + bool *courtesy_clnt) { struct list_head *tbl = nn->conf_id_hashtbl; lockdep_assert_held(&nn->client_lock); - return find_client_in_id_table(tbl, clid, sessions); + return find_client_in_id_table(tbl, clid, sessions, courtesy_clnt); } static struct nfs4_client * @@ -2883,7 +2962,7 @@ find_unconfirmed_client(clientid_t *clid, bool sessions, struct nfsd_net *nn) struct list_head *tbl = nn->unconf_id_hashtbl; lockdep_assert_held(&nn->client_lock); - return find_client_in_id_table(tbl, clid, sessions); + return find_client_in_id_table(tbl, clid, sessions, NULL); } static bool clp_used_exchangeid(struct nfs4_client *clp) @@ -2892,17 +2971,18 @@ static bool clp_used_exchangeid(struct nfs4_client *clp) } static struct nfs4_client * -find_confirmed_client_by_name(struct xdr_netobj *name, struct nfsd_net *nn) +find_confirmed_client_by_name(struct xdr_netobj *name, struct nfsd_net *nn, + bool *courtesy_clnt) { lockdep_assert_held(&nn->client_lock); - return find_clp_in_name_tree(name, &nn->conf_name_tree); + return find_clp_in_name_tree(name, &nn->conf_name_tree, courtesy_clnt); } static struct nfs4_client * find_unconfirmed_client_by_name(struct xdr_netobj *name, struct nfsd_net *nn) { lockdep_assert_held(&nn->client_lock); - return find_clp_in_name_tree(name, &nn->unconf_name_tree); + return find_clp_in_name_tree(name, &nn->unconf_name_tree, NULL); } static void @@ -3176,7 +3256,7 @@ nfsd4_exchange_id(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, /* Cases below refer to rfc 5661 section 18.35.4: */ spin_lock(&nn->client_lock); - conf = find_confirmed_client_by_name(&exid->clname, nn); + conf = find_confirmed_client_by_name(&exid->clname, nn, NULL); if (conf) { bool creds_match = same_creds(&conf->cl_cred, &rqstp->rq_cred); bool verfs_match = same_verf(&verf, &conf->cl_verifier); @@ -3443,7 +3523,7 @@ nfsd4_create_session(struct svc_rqst *rqstp, spin_lock(&nn->client_lock); unconf = find_unconfirmed_client(&cr_ses->clientid, true, nn); - conf = find_confirmed_client(&cr_ses->clientid, true, nn); + conf = find_confirmed_client(&cr_ses->clientid, true, nn, NULL); WARN_ON_ONCE(conf && unconf); if (conf) { @@ -3474,7 +3554,7 @@ nfsd4_create_session(struct svc_rqst *rqstp, status = nfserr_seq_misordered; goto out_free_conn; } - old = find_confirmed_client_by_name(&unconf->cl_name, nn); + old = find_confirmed_client_by_name(&unconf->cl_name, nn, NULL); if (old) { status = mark_client_expired_locked(old); if (status) { @@ -3613,11 +3693,13 @@ __be32 nfsd4_bind_conn_to_session(struct svc_rqst *rqstp, struct nfsd4_session *session; struct net *net = SVC_NET(rqstp); struct nfsd_net *nn = net_generic(net, nfsd_net_id); + bool courtesy_clnt; if (!nfsd4_last_compound_op(rqstp)) return nfserr_not_only_op; spin_lock(&nn->client_lock); - session = find_in_sessionid_hashtbl(&bcts->sessionid, net, &status); + session = find_in_sessionid_hashtbl(&bcts->sessionid, net, &status, + &courtesy_clnt); spin_unlock(&nn->client_lock); if (!session) goto out_no_session; @@ -3647,6 +3729,8 @@ __be32 nfsd4_bind_conn_to_session(struct svc_rqst *rqstp, out: nfsd4_put_session(session); out_no_session: + if (status == nfs_ok && courtesy_clnt) + nfsd4_client_record_create(session->se_client); return status; } @@ -3676,7 +3760,7 @@ nfsd4_destroy_session(struct svc_rqst *r, struct nfsd4_compound_state *cstate, } dump_sessionid(__func__, sessionid); spin_lock(&nn->client_lock); - ses = find_in_sessionid_hashtbl(sessionid, net, &status); + ses = find_in_sessionid_hashtbl(sessionid, net, &status, NULL); if (!ses) goto out_client_lock; status = nfserr_wrong_cred; @@ -3790,6 +3874,7 @@ nfsd4_sequence(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, int buflen; struct net *net = SVC_NET(rqstp); struct nfsd_net *nn = net_generic(net, nfsd_net_id); + bool courtesy_clnt; if (resp->opcnt != 1) return nfserr_sequence_pos; @@ -3803,7 +3888,8 @@ nfsd4_sequence(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, return nfserr_jukebox; spin_lock(&nn->client_lock); - session = find_in_sessionid_hashtbl(&seq->sessionid, net, &status); + session = find_in_sessionid_hashtbl(&seq->sessionid, net, &status, + &courtesy_clnt); if (!session) goto out_no_session; clp = session->se_client; @@ -3893,6 +3979,8 @@ nfsd4_sequence(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, if (conn) free_conn(conn); spin_unlock(&nn->client_lock); + if (status == nfs_ok && courtesy_clnt) + nfsd4_client_record_create(clp); return status; out_put_session: nfsd4_put_session_locked(session); @@ -3928,7 +4016,7 @@ nfsd4_destroy_clientid(struct svc_rqst *rqstp, spin_lock(&nn->client_lock); unconf = find_unconfirmed_client(&dc->clientid, true, nn); - conf = find_confirmed_client(&dc->clientid, true, nn); + conf = find_confirmed_client(&dc->clientid, true, nn, NULL); WARN_ON_ONCE(conf && unconf); if (conf) { @@ -4012,12 +4100,18 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, struct nfs4_client *unconf = NULL; __be32 status; struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id); + bool courtesy_clnt = false; + struct nfs4_client *cclient = NULL; new = create_client(clname, rqstp, &clverifier); if (new == NULL) return nfserr_jukebox; spin_lock(&nn->client_lock); - conf = find_confirmed_client_by_name(&clname, nn); + conf = find_confirmed_client_by_name(&clname, nn, &courtesy_clnt); + if (conf && courtesy_clnt) { + cclient = conf; + conf = NULL; + } if (conf && client_has_state(conf)) { status = nfserr_clid_inuse; if (clp_used_exchangeid(conf)) @@ -4048,7 +4142,11 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, new = NULL; status = nfs_ok; out: + if (cclient) + unhash_client_locked(cclient); spin_unlock(&nn->client_lock); + if (cclient) + expire_client(cclient); if (new) free_client(new); if (unconf) { @@ -4076,8 +4174,9 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp, return nfserr_stale_clientid; spin_lock(&nn->client_lock); - conf = find_confirmed_client(clid, false, nn); + conf = find_confirmed_client(clid, false, nn, NULL); unconf = find_unconfirmed_client(clid, false, nn); + /* * We try hard to give out unique clientid's, so if we get an * attempt to confirm the same clientid with a different cred, @@ -4107,7 +4206,7 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp, unhash_client_locked(old); nfsd4_change_callback(conf, &unconf->cl_cb_conn); } else { - old = find_confirmed_client_by_name(&unconf->cl_name, nn); + old = find_confirmed_client_by_name(&unconf->cl_name, nn, NULL); if (old) { status = nfserr_clid_inuse; if (client_has_state(old) @@ -4691,18 +4790,41 @@ nfsd_break_deleg_cb(struct file_lock *fl) return ret; } +/* + * Function returns true if lease conflict was resolved + * else returns false. + */ static bool nfsd_breaker_owns_lease(struct file_lock *fl) { struct nfs4_delegation *dl = fl->fl_owner; struct svc_rqst *rqst; struct nfs4_client *clp; + clp = dl->dl_stid.sc_client; + + /* + * need to sync with courtesy client trying to reconnect using + * the cl_cs_lock, nn->client_lock can not be used since this + * function is called with the fl_lck held. + */ + spin_lock(&clp->cl_cs_lock); + if (test_bit(NFSD4_DESTROY_COURTESY_CLIENT, &clp->cl_flags)) { + spin_unlock(&clp->cl_cs_lock); + return true; + } + if (test_bit(NFSD4_COURTESY_CLIENT, &clp->cl_flags)) { + set_bit(NFSD4_DESTROY_COURTESY_CLIENT, &clp->cl_flags); + spin_unlock(&clp->cl_cs_lock); + return true; + } + spin_unlock(&clp->cl_cs_lock); + if (!i_am_nfsd()) - return NULL; + return false; rqst = kthread_data(current); /* Note rq_prog == NFS_ACL_PROGRAM is also possible: */ if (rqst->rq_prog != NFS_PROGRAM || rqst->rq_vers < 4) - return NULL; + return false; clp = *(rqst->rq_lease_breaker); return dl->dl_stid.sc_client == clp; } @@ -4735,12 +4857,12 @@ static __be32 nfsd4_check_seqid(struct nfsd4_compound_state *cstate, struct nfs4 } static struct nfs4_client *lookup_clientid(clientid_t *clid, bool sessions, - struct nfsd_net *nn) + struct nfsd_net *nn, bool *courtesy_clnt) { struct nfs4_client *found; spin_lock(&nn->client_lock); - found = find_confirmed_client(clid, sessions, nn); + found = find_confirmed_client(clid, sessions, nn, courtesy_clnt); if (found) atomic_inc(&found->cl_rpc_users); spin_unlock(&nn->client_lock); @@ -4751,6 +4873,8 @@ static __be32 set_client(clientid_t *clid, struct nfsd4_compound_state *cstate, struct nfsd_net *nn) { + bool courtesy_clnt; + if (cstate->clp) { if (!same_clid(&cstate->clp->cl_clientid, clid)) return nfserr_stale_clientid; @@ -4762,9 +4886,12 @@ static __be32 set_client(clientid_t *clid, * We're in the 4.0 case (otherwise the SEQUENCE op would have * set cstate->clp), so session = false: */ - cstate->clp = lookup_clientid(clid, false, nn); + cstate->clp = lookup_clientid(clid, false, nn, &courtesy_clnt); if (!cstate->clp) return nfserr_expired; + + if (courtesy_clnt) + nfsd4_client_record_create(cstate->clp); return nfs_ok; } @@ -4917,9 +5044,89 @@ nfsd4_truncate(struct svc_rqst *rqstp, struct svc_fh *fh, return nfsd_setattr(rqstp, fh, &iattr, 0, (time64_t)0); } -static __be32 nfs4_get_vfs_file(struct svc_rqst *rqstp, struct nfs4_file *fp, +static bool +nfs4_check_access_deny_bmap(struct nfs4_ol_stateid *stp, u32 access, + bool share_access) +{ + if (share_access) { + if (!stp->st_deny_bmap) + return false; + + if ((stp->st_deny_bmap & (1 << NFS4_SHARE_DENY_BOTH)) || + (access & NFS4_SHARE_ACCESS_READ && + stp->st_deny_bmap & (1 << NFS4_SHARE_DENY_READ)) || + (access & NFS4_SHARE_ACCESS_WRITE && + stp->st_deny_bmap & (1 << NFS4_SHARE_DENY_WRITE))) { + return true; + } + return false; + } + if ((access & NFS4_SHARE_DENY_BOTH) || + (access & NFS4_SHARE_DENY_READ && + stp->st_access_bmap & (1 << NFS4_SHARE_ACCESS_READ)) || + (access & NFS4_SHARE_DENY_WRITE && + stp->st_access_bmap & (1 << NFS4_SHARE_ACCESS_WRITE))) { + return true; + } + return false; +} + +/* + * This function is called to check whether nfserr_share_denied should + * be returning to client. + * + * access: is op_share_access if share_access is true. + * Check if access mode, op_share_access, would conflict with + * the current deny mode of the file 'fp'. + * access: is op_share_deny if share_access is false. + * Check if the deny mode, op_share_deny, would conflict with + * current access of the file 'fp'. + * stp: skip checking this entry. + * new_stp: normal open, not open upgrade. + * + * Function returns: + * true - access/deny mode conflict with normal client. + * false - no conflict or conflict with courtesy client(s) is resolved. + */ +static bool +nfs4_conflict_clients(struct nfs4_file *fp, bool new_stp, + struct nfs4_ol_stateid *stp, u32 access, bool share_access) +{ + struct nfs4_ol_stateid *st; + struct nfs4_client *cl; + bool conflict = false; + + lockdep_assert_held(&fp->fi_lock); + list_for_each_entry(st, &fp->fi_stateids, st_perfile) { + if (st->st_openstp || (st == stp && new_stp) || + (!nfs4_check_access_deny_bmap(st, + access, share_access))) + continue; + + /* need to sync with courtesy client trying to reconnect */ + cl = st->st_stid.sc_client; + spin_lock(&cl->cl_cs_lock); + if (test_bit(NFSD4_DESTROY_COURTESY_CLIENT, &cl->cl_flags)) { + spin_unlock(&cl->cl_cs_lock); + continue; + } + if (test_bit(NFSD4_COURTESY_CLIENT, &cl->cl_flags)) { + set_bit(NFSD4_DESTROY_COURTESY_CLIENT, &cl->cl_flags); + spin_unlock(&cl->cl_cs_lock); + continue; + } + /* conflict not caused by courtesy client */ + spin_unlock(&cl->cl_cs_lock); + conflict = true; + break; + } + return conflict; +} + +static __be32 +nfs4_get_vfs_file(struct svc_rqst *rqstp, struct nfs4_file *fp, struct svc_fh *cur_fh, struct nfs4_ol_stateid *stp, - struct nfsd4_open *open) + struct nfsd4_open *open, bool new_stp) { struct nfsd_file *nf = NULL; __be32 status; @@ -4935,15 +5142,29 @@ static __be32 nfs4_get_vfs_file(struct svc_rqst *rqstp, struct nfs4_file *fp, */ status = nfs4_file_check_deny(fp, open->op_share_deny); if (status != nfs_ok) { - spin_unlock(&fp->fi_lock); - goto out; + if (status != nfserr_share_denied) { + spin_unlock(&fp->fi_lock); + goto out; + } + if (nfs4_conflict_clients(fp, new_stp, stp, + open->op_share_deny, false)) { + spin_unlock(&fp->fi_lock); + goto out; + } } /* set access to the file */ status = nfs4_file_get_access(fp, open->op_share_access); if (status != nfs_ok) { - spin_unlock(&fp->fi_lock); - goto out; + if (status != nfserr_share_denied) { + spin_unlock(&fp->fi_lock); + goto out; + } + if (nfs4_conflict_clients(fp, new_stp, stp, + open->op_share_access, true)) { + spin_unlock(&fp->fi_lock); + goto out; + } } /* Set access bits in stateid */ @@ -4994,7 +5215,7 @@ nfs4_upgrade_open(struct svc_rqst *rqstp, struct nfs4_file *fp, struct svc_fh *c unsigned char old_deny_bmap = stp->st_deny_bmap; if (!test_access(open->op_share_access, stp)) - return nfs4_get_vfs_file(rqstp, fp, cur_fh, stp, open); + return nfs4_get_vfs_file(rqstp, fp, cur_fh, stp, open, false); /* test and set deny mode */ spin_lock(&fp->fi_lock); @@ -5343,7 +5564,7 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf goto out; } } else { - status = nfs4_get_vfs_file(rqstp, fp, current_fh, stp, open); + status = nfs4_get_vfs_file(rqstp, fp, current_fh, stp, open, true); if (status) { stp->st_stid.sc_type = NFS4_CLOSED_STID; release_open_stateid(stp); @@ -5577,6 +5798,122 @@ static void nfsd4_ssc_expire_umount(struct nfsd_net *nn) } #endif +static bool +nfs4_anylock_blocker(struct nfs4_client *clp) +{ + int i; + struct nfs4_stateowner *so, *tmp; + struct nfs4_lockowner *lo; + struct nfs4_ol_stateid *stp; + struct nfs4_file *nf; + struct inode *ino; + struct file_lock_context *ctx; + struct file_lock *fl; + + spin_lock(&clp->cl_lock); + for (i = 0; i < OWNER_HASH_SIZE; i++) { + /* scan each lock owner */ + list_for_each_entry_safe(so, tmp, &clp->cl_ownerstr_hashtbl[i], + so_strhash) { + if (so->so_is_open_owner) + continue; + + /* scan lock states of this lock owner */ + lo = lockowner(so); + list_for_each_entry(stp, &lo->lo_owner.so_stateids, + st_perstateowner) { + nf = stp->st_stid.sc_file; + ino = nf->fi_inode; + ctx = ino->i_flctx; + if (!ctx) + continue; + /* check each lock belongs to this lock state */ + list_for_each_entry(fl, &ctx->flc_posix, fl_list) { + if (fl->fl_owner != lo) + continue; + if (!list_empty(&fl->fl_blocked_requests)) { + spin_unlock(&clp->cl_lock); + return true; + } + } + } + } + } + spin_unlock(&clp->cl_lock); + return false; +} + +static void +nfs4_get_client_reaplist(struct nfsd_net *nn, struct list_head *reaplist, + struct laundry_time *lt) +{ + struct list_head *pos, *next; + struct nfs4_client *clp; + bool cour; + struct list_head cslist; + + INIT_LIST_HEAD(reaplist); + INIT_LIST_HEAD(&cslist); + spin_lock(&nn->client_lock); + list_for_each_safe(pos, next, &nn->client_lru) { + clp = list_entry(pos, struct nfs4_client, cl_lru); + if (!state_expired(lt, clp->cl_time)) + break; + + /* client expired */ + if (!client_has_state(clp)) { + if (mark_client_expired_locked(clp)) + continue; + list_add(&clp->cl_lru, reaplist); + continue; + } + + /* expired client has state */ + if (test_bit(NFSD4_DESTROY_COURTESY_CLIENT, &clp->cl_flags)) + goto exp_client; + + cour = test_bit(NFSD4_COURTESY_CLIENT, &clp->cl_flags); + if (cour && + ktime_get_boottime_seconds() >= clp->courtesy_client_expiry) + goto exp_client; + + if (nfs4_anylock_blocker(clp)) { + /* expired client has state and has blocker. */ +exp_client: + if (mark_client_expired_locked(clp)) + continue; + list_add(&clp->cl_lru, reaplist); + continue; + } + /* + * Client expired and has state and has no blockers. + * If there is race condition with blockers, next time + * the laundromat runs it will catch it and expires + * the client. Client is expected to retry on lock or + * lease conflict. + */ + if (!cour) { + set_bit(NFSD4_COURTESY_CLIENT, &clp->cl_flags); + clp->courtesy_client_expiry = ktime_get_boottime_seconds() + + courtesy_client_expiry; + list_add(&clp->cl_cs_list, &cslist); + } + } + spin_unlock(&nn->client_lock); + + list_for_each_entry(clp, &cslist, cl_cs_list) { + spin_lock(&clp->cl_cs_lock); + if (test_bit(NFSD4_DESTROY_COURTESY_CLIENT, &clp->cl_flags) || + !test_bit(NFSD4_COURTESY_CLIENT, + &clp->cl_flags)) { + spin_unlock(&clp->cl_cs_lock); + continue; + } + spin_unlock(&clp->cl_cs_lock); + nfsd4_client_record_remove(clp); + } +} + static time64_t nfs4_laundromat(struct nfsd_net *nn) { @@ -5610,16 +5947,7 @@ nfs4_laundromat(struct nfsd_net *nn) } spin_unlock(&nn->s2s_cp_lock); - spin_lock(&nn->client_lock); - list_for_each_safe(pos, next, &nn->client_lru) { - clp = list_entry(pos, struct nfs4_client, cl_lru); - if (!state_expired(<, clp->cl_time)) - break; - if (mark_client_expired_locked(clp)) - continue; - list_add(&clp->cl_lru, &reaplist); - } - spin_unlock(&nn->client_lock); + nfs4_get_client_reaplist(nn, &reaplist, <); list_for_each_safe(pos, next, &reaplist) { clp = list_entry(pos, struct nfs4_client, cl_lru); trace_nfsd_clid_purged(&clp->cl_clientid); @@ -5998,7 +6326,7 @@ static __be32 find_cpntf_state(struct nfsd_net *nn, stateid_t *st, cps->cpntf_time = ktime_get_boottime_seconds(); status = nfserr_expired; - found = lookup_clientid(&cps->cp_p_clid, true, nn); + found = lookup_clientid(&cps->cp_p_clid, true, nn, NULL); if (!found) goto out; @@ -6501,6 +6829,43 @@ nfs4_transform_lock_offset(struct file_lock *lock) lock->fl_end = OFFSET_MAX; } +/** + * nfsd4_fl_lock_conflict - check if lock conflict can be resolved. + * + * @fl: pointer to file_lock with a potential conflict + * Return values: + * %true: real conflict, lock conflict can not be resolved. + * %false: no conflict, lock conflict was resolved. + * + * Note that this function is called while the flc_lock is held. + */ +static bool +nfsd4_fl_lock_conflict(struct file_lock *fl) +{ + struct nfs4_lockowner *lo; + struct nfs4_client *clp; + bool rc = true; + + if (!fl) + return true; + lo = (struct nfs4_lockowner *)fl->fl_owner; + clp = lo->lo_owner.so_client; + + /* need to sync with courtesy client trying to reconnect */ + spin_lock(&clp->cl_cs_lock); + if (test_bit(NFSD4_DESTROY_COURTESY_CLIENT, &clp->cl_flags)) + rc = false; + else { + if (test_bit(NFSD4_COURTESY_CLIENT, &clp->cl_flags)) { + set_bit(NFSD4_DESTROY_COURTESY_CLIENT, &clp->cl_flags); + rc = false; + } else + rc = true; + } + spin_unlock(&clp->cl_cs_lock); + return rc; +} + static fl_owner_t nfsd4_fl_get_owner(fl_owner_t owner) { @@ -6548,6 +6913,7 @@ static const struct lock_manager_operations nfsd_posix_mng_ops = { .lm_notify = nfsd4_lm_notify, .lm_get_owner = nfsd4_fl_get_owner, .lm_put_owner = nfsd4_fl_put_owner, + .lm_lock_conflict = nfsd4_fl_lock_conflict, }; static inline void diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h index e73bdbb1634a..b75f4c70706d 100644 --- a/fs/nfsd/state.h +++ b/fs/nfsd/state.h @@ -345,6 +345,8 @@ struct nfs4_client { #define NFSD4_CLIENT_UPCALL_LOCK (5) /* upcall serialization */ #define NFSD4_CLIENT_CB_FLAG_MASK (1 << NFSD4_CLIENT_CB_UPDATE | \ 1 << NFSD4_CLIENT_CB_KILL) +#define NFSD4_COURTESY_CLIENT (6) /* be nice to expired client */ +#define NFSD4_DESTROY_COURTESY_CLIENT (7) unsigned long cl_flags; const struct cred *cl_cb_cred; struct rpc_clnt *cl_cb_client; @@ -385,6 +387,9 @@ struct nfs4_client { struct list_head async_copies; /* list of async copies */ spinlock_t async_lock; /* lock for async copies */ atomic_t cl_cb_inflight; /* Outstanding callbacks */ + int courtesy_client_expiry; + spinlock_t cl_cs_lock; + struct list_head cl_cs_list; }; /* struct nfs4_client_reset