5.10-stable review patch. If anyone has any objections, please let me know.
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From: Jeff Layton jlayton@kernel.org
[ Upstream commit b95239ca4954a0d48b19c09ce7e8f31b453b4216 ]
queue_work can return false and not queue anything, if the work is already queued. If that happens in the case of a CB_RECALL, we'll have taken an extra reference to the stid that will never be put. Ensure we throw a warning in that case.
Signed-off-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/nfs4callback.c | 14 ++++++++++++-- fs/nfsd/nfs4state.c | 5 ++--- fs/nfsd/state.h | 2 +- 3 files changed, 15 insertions(+), 6 deletions(-)
diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c index face8908a40b1..39989c14c8a1e 100644 --- a/fs/nfsd/nfs4callback.c +++ b/fs/nfsd/nfs4callback.c @@ -1373,11 +1373,21 @@ void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, cb->cb_holds_slot = false; }
-void nfsd4_run_cb(struct nfsd4_callback *cb) +/** + * nfsd4_run_cb - queue up a callback job to run + * @cb: callback to queue + * + * Kick off a callback to do its thing. Returns false if it was already + * on a queue, true otherwise. + */ +bool nfsd4_run_cb(struct nfsd4_callback *cb) { struct nfs4_client *clp = cb->cb_clp; + bool queued;
nfsd41_cb_inflight_begin(clp); - if (!nfsd4_queue_cb(cb)) + queued = nfsd4_queue_cb(cb); + if (!queued) nfsd41_cb_inflight_end(clp); + return queued; } diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index e9fc5a357fc4d..fc6188d70796d 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -4874,14 +4874,13 @@ static void nfsd_break_one_deleg(struct nfs4_delegation *dp) * we know it's safe to take a reference. */ refcount_inc(&dp->dl_stid.sc_count); - nfsd4_run_cb(&dp->dl_recall); + WARN_ON_ONCE(!nfsd4_run_cb(&dp->dl_recall)); }
/* Called from break_lease() with flc_lock held. */ static bool nfsd_break_deleg_cb(struct file_lock *fl) { - bool ret = false; struct nfs4_delegation *dp = (struct nfs4_delegation *)fl->fl_owner; struct nfs4_file *fp = dp->dl_stid.sc_file; struct nfs4_client *clp = dp->dl_stid.sc_client; @@ -4907,7 +4906,7 @@ nfsd_break_deleg_cb(struct file_lock *fl) fp->fi_had_conflict = true; nfsd_break_one_deleg(dp); spin_unlock(&fp->fi_lock); - return ret; + return false; }
/** diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h index b3477087a9fc3..e2daef3cc0034 100644 --- a/fs/nfsd/state.h +++ b/fs/nfsd/state.h @@ -692,7 +692,7 @@ extern void nfsd4_probe_callback_sync(struct nfs4_client *clp); extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *); extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op); -extern void nfsd4_run_cb(struct nfsd4_callback *cb); +extern bool nfsd4_run_cb(struct nfsd4_callback *cb); extern int nfsd4_create_callback_queue(void); extern void nfsd4_destroy_callback_queue(void); extern void nfsd4_shutdown_callback(struct nfs4_client *);