nfsd: nfsd4_process_open2() must reference the delegation stateid

Ensure that nfsd4_process_open2() keeps a reference to the delegation
stateid until it is done working with it. Necessary step toward
client_mutex removal.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 2df6af9..5cb6305 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3325,6 +3325,8 @@ static struct nfs4_delegation *find_deleg_stateid(struct nfs4_client *cl, statei
        ret = find_stateid_by_type(cl, s, NFS4_DELEG_STID);
        if (!ret)
                return NULL;
+       /* FIXME: move into find_stateid_by_type */
+       atomic_inc(&ret->sc_count);
        return delegstateid(ret);
 }
 
@@ -3340,14 +3342,18 @@ nfs4_check_deleg(struct nfs4_client *cl, struct nfsd4_open *open,
 {
        int flags;
        __be32 status = nfserr_bad_stateid;
+       struct nfs4_delegation *deleg;
 
-       *dp = find_deleg_stateid(cl, &open->op_delegate_stateid);
-       if (*dp == NULL)
+       deleg = find_deleg_stateid(cl, &open->op_delegate_stateid);
+       if (deleg == NULL)
                goto out;
        flags = share_access_to_flags(open->op_share_access);
-       status = nfs4_check_delegmode(*dp, flags);
-       if (status)
-               *dp = NULL;
+       status = nfs4_check_delegmode(deleg, flags);
+       if (status) {
+               nfs4_put_stid(&deleg->dl_stid);
+               goto out;
+       }
+       *dp = deleg;
 out:
        if (!nfsd4_is_deleg_cur(open))
                return nfs_ok;
@@ -3828,6 +3834,8 @@ out:
        if (!(open->op_openowner->oo_flags & NFS4_OO_CONFIRMED) &&
            !nfsd4_has_session(&resp->cstate))
                open->op_rflags |= NFS4_OPEN_RESULT_CONFIRM;
+       if (dp)
+               nfs4_put_stid(&dp->dl_stid);
 
        return status;
 }