From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 55CDA3B7B71; Tue, 7 Apr 2026 13:22:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775568170; cv=none; b=n+Wg6CGa++LYHum5qJlKJtndVGkHjXqYJvRGnLQwvtR4/+ABDR17Qr+2ZjvFhHCNjxl3wAnOL2argczJI3bgzR9B7ScTSMXXC4N8/R6Uv/lOAtxkgtvNwhDzbOWfwnFiUyrOtuQ3m+W2x4eWUr1nSk3H7eqMuNReLRtSXKeVsUo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775568170; c=relaxed/simple; bh=KI9Y73gpFpkREBJqDZaHuXcw1A6OI3TbZ6+Ci8pMqFc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=CpS1A3c5M7dI9M6lSW9p9Hu8y7wDKCULkOqNi8YdG0IlwEOXI4vzJvo76XM/OiloXiGKSslpOfHHNfwi1tfCaw3CCxwaGQ348kb1+zqkV46CmOnxaItGMpjy6LxKafuDXR2jMRkQwfe4KQuo0N7s/NnisGTTN06NdJh1hwXHZ0I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=sh17iT23; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="sh17iT23" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 03880C116C6; Tue, 7 Apr 2026 13:22:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775568170; bh=KI9Y73gpFpkREBJqDZaHuXcw1A6OI3TbZ6+Ci8pMqFc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=sh17iT23RohKQT5nPmE9xYPv7QFIYIaSi+QmBmk5Iaid24c/kI6h+70ZsV2M9idpQ NbmnMJj/T0rYc8eXgznDnU09zwQto/hlRLrqYP2Es7g/ZRGib0cANAoN0dcU0XPw4Y 8DIMAt85SMdxwJB+kIh9J3ghuw3jks7UrU/joXYyr4vgbXeXsiPKRdsi502b4+V3SD IlCRtQPcdNLGciRjddH+0rqhByUnwxOW56rhhI13061WV58QIVikD8z5uP2wJ1bugY +rVKRwteOpFkHEs2Y8phx3VYab2ScPI7dwpD+oBzA9RHWS2PuufWYkDR9ZrwSb7BKM IOqz4JQtoGZxQ== From: Jeff Layton Date: Tue, 07 Apr 2026 09:21:25 -0400 Subject: [PATCH 12/24] nfsd: add data structures for handling CB_NOTIFY Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260407-dir-deleg-v1-12-aaf68c478abd@kernel.org> References: <20260407-dir-deleg-v1-0-aaf68c478abd@kernel.org> In-Reply-To: <20260407-dir-deleg-v1-0-aaf68c478abd@kernel.org> To: Alexander Viro , Christian Brauner , Jan Kara , Chuck Lever , Alexander Aring , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Jonathan Corbet , Shuah Khan , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey , Trond Myklebust , Anna Schumaker , Amir Goldstein Cc: Calum Mackay , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-nfs@vger.kernel.org, Jeff Layton X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=9027; i=jlayton@kernel.org; h=from:subject:message-id; bh=KI9Y73gpFpkREBJqDZaHuXcw1A6OI3TbZ6+Ci8pMqFc=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBp1QUHPbJV2fy3FfTxF6+BUanjoTP5HQztisfaf sHKsVqncOuJAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCadUFBwAKCRAADmhBGVaC FcScEACy+rF43hJ9TFJjTFnzIujKjQuzaohU8LprcdE2I72v6boOF/yOJB55+IgOR2l+W0vVOog G9mGmUDS1R+HWIBIs067V0Hq+8u1vknvnHJKp0xxCao2bkMKrK9D9wKkMVuhdSlhDV3pmXZTzZE ODtptmTKcoxNuxKQUpPjlFR6TUTtRsisZrFOVRumYQXymWXWbsUeIlz2ot2oebx4mi+vzEbTAl3 Gu6Sybfk5Wz37T5mYoq/OYmFK8/gHx0LgzsoSnaKoEfXrsgJIQn5XOHoZ+TJRQS9eJD4ODG9P+N Xc3AFVgWjrCJIuf8SvfRFXgmyYFGjAfAR0vNuqHRvdnE6DARqxLU2SCc2vFgkZ6ZtDqyMbjstVi 9AiNaN+f0akVpHILssHXT9zeX4yvurV/O5K/R8sWO9DRnDqnf1nor4WvraBLzAWXolVFmnN8Ljb bjD4P8ANTAsqIW2B4y3nj6FwAWZDRo3/88xN3Ol2qFtPflpGLTqB5zv5X2BwzpJscfnDRimunBZ 15PaQf1wE5BuDwAsStuDJtceVyN+HJjU0NJmBb1ySpwkl8n1EzHVegsdiJsm2ulqePZPgTFUMsy STVut9YcYH2Qe5peA/mIh+3NX4S9jfQLAwCXvXlZwYMXiutx2NEYS120Ak8xsFW6m1vK7FyaHha bTVcGPeQlaOWleQ== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 Add the data structures, allocation helpers, and callback operations needed for directory delegation CB_NOTIFY support: - struct nfsd_notify_event: carries fsnotify events for CB_NOTIFY - struct nfsd4_cb_notify: per-delegation state for notification handling - Union dl_cb_fattr with dl_cb_notify in nfs4_delegation since a delegation is either a regular file delegation or a directory delegation, never both Refactor alloc_init_deleg() into a common __alloc_init_deleg() base with a pluggable sc_free callback, and add alloc_init_dir_deleg() which allocates the page array and notify4 buffer needed for CB_NOTIFY encoding. Add skeleton nfsd4_cb_notify_ops with done/release handlers that will be filled in when the notification path is wired up. Signed-off-by: Jeff Layton --- fs/nfsd/nfs4state.c | 117 +++++++++++++++++++++++++++++++++++++++++++++------- fs/nfsd/state.h | 46 ++++++++++++++++++++- 2 files changed, 147 insertions(+), 16 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 4afe7e68fb51..b2b8c454fc0f 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -124,6 +124,7 @@ 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 struct nfsd4_callback_ops nfsd4_cb_getattr_ops; +static const struct nfsd4_callback_ops nfsd4_cb_notify_ops; static struct workqueue_struct *laundry_wq; @@ -1121,29 +1122,31 @@ static void block_delegations(struct knfsd_fh *fh) } static struct nfs4_delegation * -alloc_init_deleg(struct nfs4_client *clp, struct nfs4_file *fp, - struct nfs4_clnt_odstate *odstate, u32 dl_type) +__alloc_init_deleg(struct nfs4_client *clp, struct nfs4_file *fp, + struct nfs4_clnt_odstate *odstate, u32 dl_type, + void (*sc_free)(struct nfs4_stid *)) { struct nfs4_delegation *dp; struct nfs4_stid *stid; long n; - dprintk("NFSD alloc_init_deleg\n"); + if (delegation_blocked(&fp->fi_fhandle)) + return NULL; + n = atomic_long_inc_return(&num_delegations); if (n < 0 || n > max_delegations) goto out_dec; - if (delegation_blocked(&fp->fi_fhandle)) - goto out_dec; - stid = nfs4_alloc_stid(clp, deleg_slab, nfs4_free_deleg); + + stid = nfs4_alloc_stid(clp, deleg_slab, sc_free); if (stid == NULL) goto out_dec; - dp = delegstateid(stid); /* * delegation seqid's are never incremented. The 4.1 special * meaning of seqid 0 isn't meaningful, really, but let's avoid - * 0 anyway just for consistency and use 1: + * 0 anyway just for consistency and use 1. */ + dp = delegstateid(stid); dp->dl_stid.sc_stateid.si_generation = 1; INIT_LIST_HEAD(&dp->dl_perfile); INIT_LIST_HEAD(&dp->dl_perclnt); @@ -1153,19 +1156,75 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_file *fp, dp->dl_type = dl_type; dp->dl_retries = 1; dp->dl_recalled = false; - nfsd4_init_cb(&dp->dl_recall, dp->dl_stid.sc_client, - &nfsd4_cb_recall_ops, NFSPROC4_CLNT_CB_RECALL); - nfsd4_init_cb(&dp->dl_cb_fattr.ncf_getattr, dp->dl_stid.sc_client, - &nfsd4_cb_getattr_ops, NFSPROC4_CLNT_CB_GETATTR); - dp->dl_cb_fattr.ncf_file_modified = false; get_nfs4_file(fp); dp->dl_stid.sc_file = fp; + nfsd4_init_cb(&dp->dl_recall, dp->dl_stid.sc_client, + &nfsd4_cb_recall_ops, NFSPROC4_CLNT_CB_RECALL); return dp; out_dec: atomic_long_dec(&num_delegations); return NULL; } +static struct nfs4_delegation * +alloc_init_deleg(struct nfs4_client *clp, struct nfs4_file *fp, + struct nfs4_clnt_odstate *odstate, u32 dl_type) +{ + struct nfs4_delegation *dp; + + dp = __alloc_init_deleg(clp, fp, odstate, dl_type, nfs4_free_deleg); + if (!dp) + return NULL; + + nfsd4_init_cb(&dp->dl_cb_fattr.ncf_getattr, dp->dl_stid.sc_client, + &nfsd4_cb_getattr_ops, NFSPROC4_CLNT_CB_GETATTR); + dp->dl_cb_fattr.ncf_file_modified = false; + return dp; +} + +static void nfs4_free_dir_deleg(struct nfs4_stid *stid) +{ + struct nfs4_delegation *dp = delegstateid(stid); + struct nfsd4_cb_notify *ncn = &dp->dl_cb_notify; + int i; + + for (i = 0; i < ncn->ncn_evt_cnt; ++i) + nfsd_notify_event_put(ncn->ncn_evt[i]); + release_pages(ncn->ncn_pages, NOTIFY4_PAGE_ARRAY_SIZE); + kfree(ncn->ncn_nf); + nfs4_free_deleg(stid); +} + +static struct nfs4_delegation * +alloc_init_dir_deleg(struct nfs4_client *clp, struct nfs4_file *fp) +{ + struct nfs4_delegation *dp; + struct nfsd4_cb_notify *ncn; + int npages; + + dp = __alloc_init_deleg(clp, fp, NULL, NFS4_OPEN_DELEGATE_READ, nfs4_free_dir_deleg); + if (!dp) + return NULL; + + ncn = &dp->dl_cb_notify; + + npages = alloc_pages_bulk(GFP_KERNEL, NOTIFY4_PAGE_ARRAY_SIZE, ncn->ncn_pages); + if (npages != NOTIFY4_PAGE_ARRAY_SIZE) { + nfs4_free_dir_deleg(&dp->dl_stid); + return NULL; + } + + ncn->ncn_nf = kcalloc(NOTIFY4_EVENT_QUEUE_SIZE, sizeof(*ncn->ncn_nf), GFP_KERNEL); + if (!ncn->ncn_nf) { + nfs4_free_dir_deleg(&dp->dl_stid); + return NULL; + } + spin_lock_init(&ncn->ncn_lock); + nfsd4_init_cb(&ncn->ncn_cb, dp->dl_stid.sc_client, + &nfsd4_cb_notify_ops, NFSPROC4_CLNT_CB_NOTIFY); + return dp; +} + void nfs4_put_stid(struct nfs4_stid *s) { @@ -3381,6 +3440,30 @@ nfsd4_cb_getattr_release(struct nfsd4_callback *cb) nfs4_put_stid(&dp->dl_stid); } +static int +nfsd4_cb_notify_done(struct nfsd4_callback *cb, + struct rpc_task *task) +{ + switch (task->tk_status) { + case -NFS4ERR_DELAY: + rpc_delay(task, 2 * HZ); + return 0; + default: + return 1; + } +} + +static void +nfsd4_cb_notify_release(struct nfsd4_callback *cb) +{ + struct nfsd4_cb_notify *ncn = + container_of(cb, struct nfsd4_cb_notify, ncn_cb); + struct nfs4_delegation *dp = + container_of(ncn, struct nfs4_delegation, dl_cb_notify); + + nfs4_put_stid(&dp->dl_stid); +} + static const struct nfsd4_callback_ops nfsd4_cb_recall_any_ops = { .done = nfsd4_cb_recall_any_done, .release = nfsd4_cb_recall_any_release, @@ -3393,6 +3476,12 @@ static const struct nfsd4_callback_ops nfsd4_cb_getattr_ops = { .opcode = OP_CB_GETATTR, }; +static const struct nfsd4_callback_ops nfsd4_cb_notify_ops = { + .done = nfsd4_cb_notify_done, + .release = nfsd4_cb_notify_release, + .opcode = OP_CB_NOTIFY, +}; + static void nfs4_cb_getattr(struct nfs4_cb_fattr *ncf) { struct nfs4_delegation *dp = @@ -9661,7 +9750,7 @@ nfsd_get_dir_deleg(struct nfsd4_compound_state *cstate, /* Try to set up the lease */ status = -ENOMEM; - dp = alloc_init_deleg(clp, fp, NULL, NFS4_OPEN_DELEGATE_READ); + dp = alloc_init_dir_deleg(clp, fp); if (!dp) goto out_delegees; if (cstate->current_fh.fh_export) diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h index eb5946b0999e..500e07e47909 100644 --- a/fs/nfsd/state.h +++ b/fs/nfsd/state.h @@ -197,6 +197,44 @@ struct nfs4_cb_fattr { #define NOTIFY4_EVENT_QUEUE_SIZE 3 #define NOTIFY4_PAGE_ARRAY_SIZE 1 +struct nfsd_notify_event { + refcount_t ne_ref; // refcount + u32 ne_mask; // FS_* mask from fsnotify callback + struct dentry *ne_dentry; // dentry reference to target + u32 ne_namelen; // length of ne_name + char ne_name[]; // name of dentry being changed +}; + +static inline struct nfsd_notify_event *nfsd_notify_event_get(struct nfsd_notify_event *ne) +{ + refcount_inc(&ne->ne_ref); + return ne; +} + +static inline void nfsd_notify_event_put(struct nfsd_notify_event *ne) +{ + if (refcount_dec_and_test(&ne->ne_ref)) { + dput(ne->ne_dentry); + kfree(ne); + } +} + +/* + * Represents a directory delegation. The callback is for handling CB_NOTIFYs. + * As notifications from fsnotify come in, allocate a new event, take the ncn_lock, + * and add it to the ncn_evt queue. The CB_NOTIFY prepare handler will take the + * lock, clean out the list and process it. + */ +struct nfsd4_cb_notify { + spinlock_t ncn_lock; // protects the evt queue and count + int ncn_evt_cnt; // count of events in ncn_evt + int ncn_nf_cnt; // count of valid entries in ncn_nf + struct nfsd_notify_event *ncn_evt[NOTIFY4_EVENT_QUEUE_SIZE]; // list of events + struct page *ncn_pages[NOTIFY4_PAGE_ARRAY_SIZE]; // for encoding + struct notify4 *ncn_nf; // array of notify4's to be sent + struct nfsd4_callback ncn_cb; // notify4 callback +}; + /* * Represents a delegation stateid. The nfs4_client holds references to these * and they are put when it is being destroyed or when the delegation is @@ -233,8 +271,12 @@ struct nfs4_delegation { bool dl_written; bool dl_setattr; - /* for CB_GETATTR */ - struct nfs4_cb_fattr dl_cb_fattr; + union { + /* for CB_GETATTR */ + struct nfs4_cb_fattr dl_cb_fattr; + /* for CB_NOTIFY */ + struct nfsd4_cb_notify dl_cb_notify; + }; /* For delegated timestamps */ struct timespec64 dl_atime; -- 2.53.0