[v2,040/117] nfsd: Add reference counting to the lock and open stateids

Commit Message

Jeff Layton June 26, 2014, 7:12 p.m. UTC

From: Trond Myklebust <[e-mail]>

When we remove the client_mutex, we'll need to be able to ensure that
these objects aren't destroyed while we're not holding locks.

Signed-off-by: Trond Myklebust <[e-mail]>
---
 fs/nfsd/nfs4state.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

Patch

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 78b90880d291..cad93b38f20b 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -872,8 +872,10 @@  static void close_generic_stateid(struct nfs4_ol_stateid *stp)
 	release_all_access(stp);
 }
 
-static void free_generic_stateid(struct nfs4_ol_stateid *stp)
+static void put_generic_stateid(struct nfs4_ol_stateid *stp)
 {
+	if (!atomic_dec_and_test(&stp->st_stid.sc_count))
+		return;
 	remove_stid(&stp->st_stid);
 	if (stp->st_file)
 		put_nfs4_file(stp->st_file);
@@ -891,7 +893,7 @@  static void __release_lock_stateid(struct nfs4_ol_stateid *stp)
 	if (file)
 		filp_close(file, (fl_owner_t)lockowner(stp->st_stateowner));
 	close_generic_stateid(stp);
-	free_generic_stateid(stp);
+	put_generic_stateid(stp);
 }
 
 static void unhash_lockowner(struct nfs4_lockowner *lo)
@@ -954,7 +956,7 @@  static void unhash_open_stateid(struct nfs4_ol_stateid *stp)
 static void release_open_stateid(struct nfs4_ol_stateid *stp)
 {
 	unhash_open_stateid(stp);
-	free_generic_stateid(stp);
+	put_generic_stateid(stp);
 }
 
 static void unhash_openowner(struct nfs4_openowner *oo)
@@ -975,7 +977,7 @@  static void release_last_closed_stateid(struct nfs4_openowner *oo)
 	struct nfs4_ol_stateid *s = oo->oo_last_closed_stid;
 
 	if (s) {
-		free_generic_stateid(s);
+		put_generic_stateid(s);
 		oo->oo_last_closed_stid = NULL;
 	}
 }
@@ -3742,7 +3744,7 @@  void nfsd4_cleanup_open_state(struct nfsd4_open *open, __be32 status)
 	if (open->op_file)
 		nfsd4_free_file(open->op_file);
 	if (open->op_stp)
-		free_generic_stateid(open->op_stp);
+		put_generic_stateid(open->op_stp);
 }
 
 static __be32 lookup_clientid(clientid_t *clid,
@@ -4435,9 +4437,9 @@  static void nfsd4_close_open_stateid(struct nfs4_ol_stateid *s)
 	unhash_open_stateid(s);
 
 	if (clp->cl_minorversion) {
-		free_generic_stateid(s);
 		if (list_empty(&oo->oo_owner.so_stateids))
 			release_openowner(oo);
+		put_generic_stateid(s);
 	} else {
 		if (s->st_file) {
 			put_nfs4_file(s->st_file);