nfsd: Add a mutex to protect the NFSv4.0 open owner replay cache
We don't want to rely on the client_mutex for protection in the case of
NFSv4 open owners. Instead, we add a mutex that will only be taken for
NFSv4.0 state mutating operations, and that will be released once the
entire compound is done.
Also, ensure that nfsd4_cstate_assign_replay/nfsd4_cstate_clear_replay
take a reference to the stateowner when they are using it for NFSv4.0
open and lock replay caching.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 5a93e5f..749608b 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1069,7 +1069,7 @@
return;
if (!seqid_mutating_err(ntohl(nfserr))) {
- cstate->replay_owner = NULL;
+ nfsd4_cstate_clear_replay(cstate);
return;
}
if (!so)
@@ -2940,6 +2940,28 @@
rp->rp_status = nfserr_serverfault;
rp->rp_buflen = 0;
rp->rp_buf = rp->rp_ibuf;
+ mutex_init(&rp->rp_mutex);
+}
+
+static void nfsd4_cstate_assign_replay(struct nfsd4_compound_state *cstate,
+ struct nfs4_stateowner *so)
+{
+ if (!nfsd4_has_session(cstate)) {
+ mutex_lock(&so->so_replay.rp_mutex);
+ cstate->replay_owner = so;
+ atomic_inc(&so->so_count);
+ }
+}
+
+void nfsd4_cstate_clear_replay(struct nfsd4_compound_state *cstate)
+{
+ struct nfs4_stateowner *so = cstate->replay_owner;
+
+ if (so != NULL) {
+ cstate->replay_owner = NULL;
+ mutex_unlock(&so->so_replay.rp_mutex);
+ nfs4_put_stateowner(so);
+ }
}
static inline void *alloc_stateowner(struct kmem_cache *slab, struct xdr_netobj *owner, struct nfs4_client *clp)
@@ -3855,7 +3877,8 @@
return status;
}
-void nfsd4_cleanup_open_state(struct nfsd4_open *open, __be32 status)
+void nfsd4_cleanup_open_state(struct nfsd4_compound_state *cstate,
+ struct nfsd4_open *open, __be32 status)
{
if (open->op_openowner) {
struct nfs4_openowner *oo = open->op_openowner;
@@ -3869,6 +3892,8 @@
} else
oo->oo_flags &= ~NFS4_OO_NEW;
}
+ if (open->op_openowner)
+ nfsd4_cstate_assign_replay(cstate, &oo->oo_owner);
}
if (open->op_file)
nfsd4_free_file(open->op_file);
@@ -4399,8 +4424,7 @@
if (status)
return status;
stp = openlockstateid(s);
- if (!nfsd4_has_session(cstate))
- cstate->replay_owner = stp->st_stateowner;
+ nfsd4_cstate_assign_replay(cstate, stp->st_stateowner);
status = nfs4_seqid_op_checks(cstate, stateid, seqid, stp);
if (!status)
@@ -4469,8 +4493,7 @@
nfs4_put_stid(&stp->st_stid);
out:
nfsd4_bump_seqid(cstate, status);
- if (!cstate->replay_owner)
- nfs4_unlock_state();
+ nfs4_unlock_state();
return status;
}
@@ -4544,8 +4567,7 @@
nfs4_put_stid(&stp->st_stid);
out:
nfsd4_bump_seqid(cstate, status);
- if (!cstate->replay_owner)
- nfs4_unlock_state();
+ nfs4_unlock_state();
return status;
}
@@ -4610,8 +4632,7 @@
/* put reference from nfs4_preprocess_seqid_op */
nfs4_put_stid(&stp->st_stid);
out:
- if (!cstate->replay_owner)
- nfs4_unlock_state();
+ nfs4_unlock_state();
return status;
}
@@ -5071,8 +5092,7 @@
if (status && new_state)
release_lock_stateid(lock_stp);
nfsd4_bump_seqid(cstate, status);
- if (!cstate->replay_owner)
- nfs4_unlock_state();
+ nfs4_unlock_state();
if (file_lock)
locks_free_lock(file_lock);
if (conflock)
@@ -5236,8 +5256,7 @@
nfs4_put_stid(&stp->st_stid);
out:
nfsd4_bump_seqid(cstate, status);
- if (!cstate->replay_owner)
- nfs4_unlock_state();
+ nfs4_unlock_state();
if (file_lock)
locks_free_lock(file_lock);
return status;