[PATCH RFC v2 23/28] nfsd: make nfsd4_callback_ops->prepare operation bool return

[Jeff Layton <jlayton@kernel.org>]

For a CB_NOTIFY operation, we need to stop processing the callback
if an allocation fails. Change the ->prepare callback operation to
return true if processing should continue, and false otherwise.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/nfsd/nfs4callback.c | 5 ++++-
 fs/nfsd/nfs4layouts.c  | 3 ++-
 fs/nfsd/nfs4state.c    | 6 ++++--
 fs/nfsd/state.h        | 6 +++---
 4 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 2dca686d67fc0f0fcf7997a252b4f5988b9de6c7..fe7b20b94d76efd309e27c1a3ef359e7101dac80 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -1785,7 +1785,10 @@ nfsd4_run_cb_work(struct work_struct *work)
 
 	if (!test_and_clear_bit(NFSD4_CALLBACK_REQUEUE, &cb->cb_flags)) {
 		if (cb->cb_ops && cb->cb_ops->prepare)
-			cb->cb_ops->prepare(cb);
+			if (!cb->cb_ops->prepare(cb)) {
+				nfsd41_destroy_cb(cb);
+				return;
+			}
 	}
 
 	cb->cb_msg.rpc_cred = clp->cl_cb_cred;
diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
index 290271ac424540e4405a5fd0eacc8db9f47603cd..f23699998e4c978b4af0c87cc0a959851ef5ac4b 100644
--- a/fs/nfsd/nfs4layouts.c
+++ b/fs/nfsd/nfs4layouts.c
@@ -653,7 +653,7 @@ nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls, struct nfsd_file *file)
 	}
 }
 
-static void
+static bool
 nfsd4_cb_layout_prepare(struct nfsd4_callback *cb)
 {
 	struct nfs4_layout_stateid *ls =
@@ -662,6 +662,7 @@ nfsd4_cb_layout_prepare(struct nfsd4_callback *cb)
 	mutex_lock(&ls->ls_mutex);
 	nfs4_inc_and_copy_stateid(&ls->ls_recall_sid, &ls->ls_stid);
 	mutex_unlock(&ls->ls_mutex);
+	return true;
 }
 
 static int
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 164020a01b737f76d2780b30274e75dcc3def819..5860d44fea0a4f854d65c87bcacb8eea19ce82e4 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -362,12 +362,13 @@ remove_blocked_locks(struct nfs4_lockowner *lo)
 	}
 }
 
-static void
+static bool
 nfsd4_cb_notify_lock_prepare(struct nfsd4_callback *cb)
 {
 	struct nfsd4_blocked_lock	*nbl = container_of(cb,
 						struct nfsd4_blocked_lock, nbl_cb);
 	locks_delete_block(&nbl->nbl_lock);
+	return true;
 }
 
 static int
@@ -5482,7 +5483,7 @@ bool nfsd_wait_for_delegreturn(struct svc_rqst *rqstp, struct inode *inode)
 	return timeo > 0;
 }
 
-static void nfsd4_cb_recall_prepare(struct nfsd4_callback *cb)
+static bool nfsd4_cb_recall_prepare(struct nfsd4_callback *cb)
 {
 	struct nfs4_delegation *dp = cb_to_delegation(cb);
 	struct nfsd_net *nn = net_generic(dp->dl_stid.sc_client->net,
@@ -5503,6 +5504,7 @@ static void nfsd4_cb_recall_prepare(struct nfsd4_callback *cb)
 		list_add_tail(&dp->dl_recall_lru, &nn->del_recall_lru);
 	}
 	spin_unlock(&state_lock);
+	return true;
 }
 
 static int nfsd4_cb_recall_done(struct nfsd4_callback *cb,
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 706bbc7076a4f1d0be3ea7067d193683821d74eb..98f87fa724ee242f3a855faa205223b0e09a16ed 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -97,9 +97,9 @@ struct nfsd4_callback {
 };
 
 struct nfsd4_callback_ops {
-	void (*prepare)(struct nfsd4_callback *);
-	int (*done)(struct nfsd4_callback *, struct rpc_task *);
-	void (*release)(struct nfsd4_callback *);
+	bool (*prepare)(struct nfsd4_callback *cb);
+	int (*done)(struct nfsd4_callback *cb, struct rpc_task *task);
+	void (*release)(struct nfsd4_callback *cb);
 	uint32_t opcode;
 };
 

-- 
2.49.0