[PATCH 6/8] nfsd4: introduce nfs4_client.cl_refcount

Benny Halevy
2010-05-04T22:44:44Z

Currently just initialize the cl_refcount to 1
and decrement in expire_client(), conditionally freeing the
client when the refcount reaches 0.

To be used later by nfsv4.1 compounds to keep the client from
timing out while in use.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
---
fs/nfsd/nfs4state.c | 5 ++++-
fs/nfsd/state.h | 1 +
2 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index cd02567..4b1d39f 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -739,8 +739,10 @@ expire_client(struct nfs4_client *clp)
list_del(&clp->cl_strhash);
spin_lock(&client_lock);
unhash_client_locked(clp);
+ BUG_ON(clp->cl_refcount <= 0);
+ if (--clp->cl_refcount <= 0)
+ free_client(clp);
spin_unlock(&client_lock);
- free_client(clp);
}

static void copy_verf(struct nfs4_client *target, nfs4_verifier *source)
@@ -826,6 +828,7 @@ static struct nfs4_client *create_client(struct xdr_netobj name, char *recdir,
}

memcpy(clp->cl_recdir, recdir, HEXDIR_LEN);
+ clp->cl_refcount = 1;
atomic_set(&clp->cl_cb_set, 0);
INIT_LIST_HEAD(&clp->cl_idhash);
INIT_LIST_HEAD(&clp->cl_strhash);
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 98836fd..09c827d 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -233,6 +233,7 @@ struct nfs4_client {
struct nfsd4_clid_slot cl_cs_slot; /* create_session slot */
u32 cl_exchange_flags;
struct nfs4_sessionid cl_sessionid;
+ int cl_refcount; /* use under client_lock */

/* for nfs41 callbacks */
/* We currently support a single back channel with a single slot */
--
1.6.5.1