From: Chuck Lever <chuck.lever@oracle.com>

Add an sc_export field to struct nfs4_stid so that each stateid
records the export under which it was acquired.  The export
reference is taken via exp_get() at stateid creation and released
via exp_put() in nfs4_put_stid().

Open stateids record the export from current_fh->fh_export.
Lock stateids and delegations inherit the export from their
parent open stateid. Layout stateids inherit from their
parent stateid. Directory delegations record the export from
cstate->current_fh.

A subsequent commit uses sc_export to scope state revocation to a
specific export, avoiding the need to walk inode dentry aliases at
revocation time.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs4layouts.c |  2 ++
 fs/nfsd/nfs4state.c   | 16 +++++++++++++++-
 fs/nfsd/state.h       |  1 +
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
index 69e41105efdd..83d8fda53efd 100644
--- a/fs/nfsd/nfs4layouts.c
+++ b/fs/nfsd/nfs4layouts.c
@@ -247,6 +247,8 @@ nfsd4_alloc_layout_stateid(struct nfsd4_compound_state *cstate,
 
 	get_nfs4_file(fp);
 	stp->sc_file = fp;
+	if (parent->sc_export)
+		stp->sc_export = exp_get(parent->sc_export);
 
 	ls = layoutstateid(stp);
 	INIT_LIST_HEAD(&ls->ls_perclnt);
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 62ebc7243c4f..ebbc83d7877e 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1168,6 +1168,7 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_file *fp,
 void
 nfs4_put_stid(struct nfs4_stid *s)
 {
+	struct svc_export *exp = s->sc_export;
 	struct nfs4_file *fp = s->sc_file;
 	struct nfs4_client *clp = s->sc_client;
 
@@ -1183,6 +1184,8 @@ nfs4_put_stid(struct nfs4_stid *s)
 	nfs4_free_cpntf_statelist(clp->net, s);
 	spin_unlock(&clp->cl_lock);
 	s->sc_free(s);
+	if (exp)
+		exp_put(exp);
 	if (fp)
 		put_nfs4_file(fp);
 }
@@ -6172,6 +6175,8 @@ nfs4_set_delegation(struct nfsd4_open *open, struct nfs4_ol_stateid *stp,
 	dp = alloc_init_deleg(clp, fp, odstate, dl_type);
 	if (!dp)
 		goto out_delegees;
+	if (stp->st_stid.sc_export)
+		dp->dl_stid.sc_export = exp_get(stp->st_stid.sc_export);
 
 	fl = nfs4_alloc_init_lease(dp);
 	if (!fl)
@@ -6506,8 +6511,11 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
 			goto out;
 		}
 
-		if (!open->op_stp)
+		if (!open->op_stp) {
 			new_stp = true;
+			stp->st_stid.sc_export =
+				exp_get(current_fh->fh_export);
+		}
 	}
 
 	/*
@@ -8203,6 +8211,9 @@ init_lock_stateid(struct nfs4_ol_stateid *stp, struct nfs4_lockowner *lo,
 	stp->st_stateowner = nfs4_get_stateowner(&lo->lo_owner);
 	get_nfs4_file(fp);
 	stp->st_stid.sc_file = fp;
+	if (open_stp->st_stid.sc_export)
+		stp->st_stid.sc_export =
+			exp_get(open_stp->st_stid.sc_export);
 	stp->st_access_bmap = 0;
 	stp->st_deny_bmap = open_stp->st_deny_bmap;
 	stp->st_openstp = open_stp;
@@ -9529,6 +9540,9 @@ nfsd_get_dir_deleg(struct nfsd4_compound_state *cstate,
 	dp = alloc_init_deleg(clp, fp, NULL, NFS4_OPEN_DELEGATE_READ);
 	if (!dp)
 		goto out_delegees;
+	if (cstate->current_fh.fh_export)
+		dp->dl_stid.sc_export =
+			exp_get(cstate->current_fh.fh_export);
 
 	fl = nfs4_alloc_init_lease(dp);
 	if (!fl)
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 953675eba5c3..7d7e99eeffa5 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -145,6 +145,7 @@ struct nfs4_stid {
 	spinlock_t		sc_lock;
 	struct nfs4_client	*sc_client;
 	struct nfs4_file	*sc_file;
+	struct svc_export	*sc_export;
 	void			(*sc_free)(struct nfs4_stid *);
 };
 

-- 
2.53.0