nfsd: clean up refcounting for lockowners

Ensure that lockowner references are only held by lockstateids and
operations that are in-progress. With this, we can get rid of
release_lockowner_if_empty, which will be racy once we remove
client_mutex protection.

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 88225f0bbc124934e631dfa7c72501f371883022..c86fe66254b0b8321e4fe931c17d0d9ff5defb59 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -933,7 +933,7 @@ static void nfs4_free_lock_stateid(struct nfs4_stid *stid)
        nfs4_free_ol_stateid(stid);
 }
 
-static void __release_lock_stateid(struct nfs4_ol_stateid *stp)
+static void release_lock_stateid(struct nfs4_ol_stateid *stp)
 {
        struct nfs4_openowner *oo = openowner(stp->st_openstp->st_stateowner);
 
@@ -957,7 +957,7 @@ static void release_lockowner_stateids(struct nfs4_lockowner *lo)
        while (!list_empty(&lo->lo_owner.so_stateids)) {
                stp = list_first_entry(&lo->lo_owner.so_stateids,
                                struct nfs4_ol_stateid, st_perstateowner);
-               __release_lock_stateid(stp);
+               release_lock_stateid(stp);
        }
 }
 
@@ -968,21 +968,6 @@ static void release_lockowner(struct nfs4_lockowner *lo)
        nfs4_put_stateowner(&lo->lo_owner);
 }
 
-static void release_lockowner_if_empty(struct nfs4_lockowner *lo)
-{
-       if (list_empty(&lo->lo_owner.so_stateids))
-               release_lockowner(lo);
-}
-
-static void release_lock_stateid(struct nfs4_ol_stateid *stp)
-{
-       struct nfs4_lockowner *lo;
-
-       lo = lockowner(stp->st_stateowner);
-       __release_lock_stateid(stp);
-       release_lockowner_if_empty(lo);
-}
-
 static void release_open_stateid_locks(struct nfs4_ol_stateid *open_stp)
        __releases(&open_stp->st_stateowner->so_client->cl_lock)
        __acquires(&open_stp->st_stateowner->so_client->cl_lock)
@@ -4323,7 +4308,7 @@ nfsd4_free_lock_stateid(struct nfs4_ol_stateid *stp)
 
        if (check_for_locks(stp->st_stid.sc_file, lo))
                return nfserr_locks_held;
-       release_lockowner_if_empty(lo);
+       release_lock_stateid(stp);
        return nfs_ok;
 }
 
@@ -4938,8 +4923,6 @@ lookup_or_create_lock_state(struct nfsd4_compound_state *cstate,
                lo = alloc_init_lock_stateowner(strhashval, cl, ost, lock);
                if (lo == NULL)
                        return nfserr_jukebox;
-               /* FIXME: extra reference for new lockowners for the client */
-               atomic_inc(&lo->lo_owner.so_count);
        } else {
                /* with an existing lockowner, seqids must be the same */
                status = nfserr_bad_seqid;
@@ -4950,7 +4933,6 @@ lookup_or_create_lock_state(struct nfsd4_compound_state *cstate,
 
        *lst = find_or_create_lock_stateid(lo, fi, inode, ost, new);
        if (*lst == NULL) {
-               release_lockowner_if_empty(lo);
                status = nfserr_jukebox;
                goto out;
        }
@@ -5379,6 +5361,7 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp,
                        continue;
                if (same_owner_str(tmp, owner, clid)) {
                        sop = tmp;
+                       atomic_inc(&sop->so_count);
                        break;
                }
        }
@@ -5392,8 +5375,10 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp,
        lo = lockowner(sop);
        /* see if there are still any locks associated with it */
        list_for_each_entry(stp, &sop->so_stateids, st_perstateowner) {
-               if (check_for_locks(stp->st_stid.sc_file, lo))
+               if (check_for_locks(stp->st_stid.sc_file, lo)) {
+                       nfs4_put_stateowner(sop);
                        goto out;
+               }
        }
 
        status = nfs_ok;