Post r223774, the NFSv4 client no longer has multiple instances

of the same lock_owner4 string. As such, the handling of cleanup
of lock_owners could be simplified. This simplification permitted
the client to do a ReleaseLockOwner operation when the process that
the lock_owner4 string represents, has exited. This permits the
server to release any storage related to the lock_owner4 string
before the associated open is closed. Without this change, it
is possible to exhaust a server's storage when a long running
process opens a file and then many child processes do locking
on the file, because the open doesn't get closed. A similar patch
was applied to the Linux NFSv4 client recently so that it wouldn't
exhaust a server's storage.

Reviewed by:	zack
MFC after:	2 weeks

1 files changed, 10 insertions, 1 deletions

diff --git a/sys/fs/nfs/nfsclstate.h b/sys/fs/nfs/nfsclstate.h
index 006ef3f..868e7cf 100644
--- a/sys/fs/nfs/nfsclstate.h
+++ b/sys/fs/nfs/nfsclstate.h
@@ -34,6 +34,7 @@
  */
 LIST_HEAD(nfsclopenhead, nfsclopen);
 LIST_HEAD(nfscllockownerhead, nfscllockowner);
+SLIST_HEAD(nfscllockownerfhhead, nfscllockownerfh);
 LIST_HEAD(nfscllockhead, nfscllock);
 LIST_HEAD(nfsclhead, nfsclclient);
 LIST_HEAD(nfsclownerhead, nfsclowner);
@@ -149,8 +150,8 @@ struct nfscllockowner {
 	struct nfsclopen	*nfsl_open;
 	NFSPROC_T		*nfsl_inprog;
 	nfsv4stateid_t		nfsl_stateid;
+	int			nfsl_lockflags;
 	u_int32_t		nfsl_seqid;
-	u_int32_t		nfsl_defunct;
 	struct nfsv4lock	nfsl_rwlock;
 	u_int8_t		nfsl_owner[NFSV4CL_LOCKNAMELEN];
 	u_int8_t		nfsl_openowner[NFSV4CL_LOCKNAMELEN];
@@ -166,6 +167,14 @@ struct nfscllock {
 	short			nfslo_type;
 };
 
+/* This structure is used to collect a list of lockowners to free up. */
+struct nfscllockownerfh {
+	SLIST_ENTRY(nfscllockownerfh)	nfslfh_list;
+	struct nfscllockownerhead	nfslfh_lock;
+	int				nfslfh_len;
+	uint8_t				nfslfh_fh[NFSX_V4FHMAX];
+};
+
 /*
  * Macro for incrementing the seqid#.
  */