2022-04-06 22:51:41

by Dai Ngo

[permalink] [raw]
Subject: [PATCH RFC v20 02/10] NFSD: Add lm_lock_expired call out

Add callout function nfsd4_lm_lock_expired for lm_lock_expired.
If lock request has conflict with courtesy client then expire the
courtesy client and return no conflict to caller.

Signed-off-by: Dai Ngo <[email protected]>
---
fs/nfsd/nfs4state.c | 22 ++++++++++++++++++++++
fs/nfsd/state.h | 14 ++++++++++++++
2 files changed, 36 insertions(+)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index a65d59510681..80772662236b 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -6578,10 +6578,32 @@ nfsd4_lm_notify(struct file_lock *fl)
}
}

+/**
+ * nfsd4_lm_lock_expired - check if lock conflict can be resolved.
+ *
+ * @fl: pointer to file_lock with a potential conflict
+ * Return values:
+ * %false: real conflict, lock conflict can not be resolved.
+ * %true: no conflict, lock conflict was resolved.
+ *
+ * Note that this function is called while the flc_lock is held.
+ */
+static bool
+nfsd4_lm_lock_expired(struct file_lock *fl)
+{
+ struct nfs4_lockowner *lo;
+
+ if (!fl)
+ return false;
+ lo = (struct nfs4_lockowner *)fl->fl_owner;
+ return nfsd4_expire_courtesy_clnt(lo->lo_owner.so_client);
+}
+
static const struct lock_manager_operations nfsd_posix_mng_ops = {
.lm_notify = nfsd4_lm_notify,
.lm_get_owner = nfsd4_lm_get_owner,
.lm_put_owner = nfsd4_lm_put_owner,
+ .lm_lock_expired = nfsd4_lm_lock_expired,
};

static inline void
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 7f78da5d1408..8b81493ee48a 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -735,4 +735,18 @@ extern void nfsd4_client_record_remove(struct nfs4_client *clp);
extern int nfsd4_client_record_check(struct nfs4_client *clp);
extern void nfsd4_record_grace_done(struct nfsd_net *nn);

+static inline bool
+nfsd4_expire_courtesy_clnt(struct nfs4_client *clp)
+{
+ bool rc = false;
+
+ spin_lock(&clp->cl_cs_lock);
+ if (clp->cl_cs_client_state == NFSD4_CLIENT_COURTESY)
+ clp->cl_cs_client_state = NFSD4_CLIENT_EXPIRED;
+ if (clp->cl_cs_client_state == NFSD4_CLIENT_EXPIRED)
+ rc = true;
+ spin_unlock(&clp->cl_cs_lock);
+ return rc;
+}
+
#endif /* NFSD4_STATE_H */
--
2.9.5