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 E2AED3E3DA5; Thu, 16 Apr 2026 17:35:50 +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=1776360951; cv=none; b=BP3ZUFxNFW0miDNdAO8lUEEDVZlnxFQZ+jHLSP2+15tiIkADyKagC4mKjsJiXL1+/fi5qcI7xJt98VmZTbSVAMv9knSOS+IRnT3r8lvP/edsH6iPlqJsxZcoCKDT8HGjZLdLOLN2SN0TX3jVz8zQH4maMlZ2asX/Q2I0lJDW/x4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776360951; c=relaxed/simple; bh=Nk+Hk9zcNVhLvAPUEL4gA5EfzqizEie4iShWDqU6Hfw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=gLhZWTF3tmRUwL2BQ82+SV1rQ3jFDrveq1g3FEaOyiNeeioVDhA83njSUquOHRchUqci2Vod5RpcB+LRxVuU7lAcyE6xCeCygqsHmJSO82VKmDbuCo2FjIqbwhgaSyHw4aehz8SrT0sWbgUJyM5l48MPMAoWbnDAtI9tlEQ53RM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kj+7i0pU; 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="kj+7i0pU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 073ECC2BCB0; Thu, 16 Apr 2026 17:35:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776360950; bh=Nk+Hk9zcNVhLvAPUEL4gA5EfzqizEie4iShWDqU6Hfw=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=kj+7i0pUwpDdWbjv7vvPoTye7Il5NTJB+i//3U6Qsmao2241WimsBi/lhnNMkELRj ZScINtKuWhUDBNk2Co0CdIOHscBPbHoxl2/+EoFn+xehGWR3imN1afL8hXalp91vK4 IJOlz8OYpEQQ1qgxC+EgpUgxDnw/JlSve1IXWfmRhM1Xr5AbFYnBEiIFRoNlN1ithA mtecqZ3d1/kca3ie8G4DBYQCW2np/9oelosm9kFYw4MUZ3IJuJ5JB69be+Z5usQfoh 1QjW+uJu72HIrLEO0vsykQLZ7rTW9IWPBHf7i8G6A0qXJvez+U+6PbFTzwCrJ+ae1e yLm25lMMT2VUA== From: Jeff Layton Date: Thu, 16 Apr 2026 10:35:17 -0700 Subject: [PATCH v2 16/28] nfsd: add data structures for handling CB_NOTIFY Precedence: bulk X-Mailing-List: linux-fsdevel@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: <20260416-dir-deleg-v2-16-851426a550f6@kernel.org> References: <20260416-dir-deleg-v2-0-851426a550f6@kernel.org> In-Reply-To: <20260416-dir-deleg-v2-0-851426a550f6@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=9015; i=jlayton@kernel.org; h=from:subject:message-id; bh=Nk+Hk9zcNVhLvAPUEL4gA5EfzqizEie4iShWDqU6Hfw=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBp4R3lqwKItNMQ/NB3i04nee6wIsTYntJCphsXG e7YySTNAliJAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCaeEd5QAKCRAADmhBGVaC FR0YEAC9I4QnglLLdayZd2OdQQkSO2kNpQfnsNDY3JJ2aMNsLW1G3GgrOiz4B8bWKznAp/fUGJ1 nrdbK2nFRuf4lXDQPaY27YNiIWbgQkqK8q29GcZeQ8Bs0zhAaVDcopcg4rM+kX2AeoWkJQNUWxv eULgxXP4mkAjE48X42H6fM+ANY0w4qGoUEb4vD8xQCGx1L+nYNcF8kYceSprnqDCGc9thXnwTqd 5bhzV/2OlTQff5bauE5v4Ovxi+gcHZ9o38Ojm4MK0+hgCJkU3zjowClg4CoYv3rcHMpoRZwPHwl JBjTg4maAu2lAit0nZhetYkVWKtJ7fc0gi3i5fFjpZLWf2bLd9tRj0nu0BHntknxWgRTlnb618a PDiX80teJKrDUfU4nFIOn+s2hEhAS1yb3zsvqI9+ToZ+282+Jl2Ipu4HJMiteqa1diPc8oZaVyy STwcplguQSinBIspCTXD/xok5wu5+3b9/Q1GG0Z2mNK7GZ1cbKTiulB/Fe29CrGA9JtLCzdnAxb bi5DWM8G2F+WKbc9uRcAGHaxaO/Fzi/73GaeDxkrPzmxrNqODP27uYYDPbabHfnF4fh3xmdx0QF n84hABUkCaRYyiZxan0EnL4dmzleaolUAdeLfhnuA4xc2PerWT0jOLFTLQF4fr+F1H/dga9YjE9 5NE1uYdEb93A1pg== 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 ef04e26b4f30..eefce9e7c628 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -126,6 +126,7 @@ 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; @@ -1123,29 +1124,31 @@ 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); @@ -1155,19 +1158,75 @@ 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_put_stid(&dp->dl_stid); + return NULL; + } + + ncn->ncn_nf = kcalloc(NOTIFY4_EVENT_QUEUE_SIZE, sizeof(*ncn->ncn_nf), GFP_KERNEL); + if (!ncn->ncn_nf) { + nfs4_put_stid(&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) { @@ -3389,6 +3448,30 @@ 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, @@ -3401,6 +3484,12 @@ 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 = @@ -9683,7 +9772,7 @@ 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