nfsd: Add reference counting to the lock and open stateids
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.
Add a ->free() callback to the struct nfs4_stid, so that we can
release a reference to the stid without caring about the contents.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index b0f83be..60ab22b 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -71,6 +71,7 @@
/* forward declarations */
static bool check_for_locks(struct nfs4_file *fp, struct nfs4_lockowner *lowner);
+static void nfs4_free_ol_stateid(struct nfs4_stid *stid);
/* Locking: */
@@ -463,8 +464,8 @@
__nfs4_file_put_access(fp, O_RDONLY);
}
-static struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct
-kmem_cache *slab)
+static struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl,
+ struct kmem_cache *slab)
{
struct idr *stateids = &cl->cl_stateids;
struct nfs4_stid *stid;
@@ -500,7 +501,26 @@
static struct nfs4_ol_stateid * nfs4_alloc_stateid(struct nfs4_client *clp)
{
- return openlockstateid(nfs4_alloc_stid(clp, stateid_slab));
+ struct nfs4_stid *stid;
+ struct nfs4_ol_stateid *stp;
+
+ stid = nfs4_alloc_stid(clp, stateid_slab);
+ if (!stid)
+ return NULL;
+
+ stp = openlockstateid(stid);
+ stp->st_stid.sc_free = nfs4_free_ol_stateid;
+ return stp;
+}
+
+static void nfs4_free_deleg(struct nfs4_stid *stid)
+{
+ struct nfs4_delegation *dp = delegstateid(stid);
+
+ if (dp->dl_file)
+ put_nfs4_file(dp->dl_file);
+ kmem_cache_free(deleg_slab, stid);
+ atomic_long_dec(&num_delegations);
}
/*
@@ -594,6 +614,8 @@
dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab));
if (dp == NULL)
goto out_dec;
+
+ dp->dl_stid.sc_free = nfs4_free_deleg;
/*
* delegation seqid's are never incremented. The 4.1 special
* meaning of seqid 0 isn't meaningful, really, but let's avoid
@@ -611,28 +633,15 @@
return NULL;
}
-static void remove_stid(struct nfs4_stid *s)
-{
- struct idr *stateids = &s->sc_client->cl_stateids;
-
- idr_remove(stateids, s->sc_stateid.si_opaque.so_id);
-}
-
-static void nfs4_free_stid(struct kmem_cache *slab, struct nfs4_stid *s)
-{
- kmem_cache_free(slab, s);
-}
-
void
-nfs4_put_delegation(struct nfs4_delegation *dp)
+nfs4_put_stid(struct nfs4_stid *s)
{
- if (atomic_dec_and_test(&dp->dl_stid.sc_count)) {
- if (dp->dl_file)
- put_nfs4_file(dp->dl_file);
- remove_stid(&dp->dl_stid);
- nfs4_free_stid(deleg_slab, &dp->dl_stid);
- atomic_long_dec(&num_delegations);
- }
+ struct nfs4_client *clp = s->sc_client;
+
+ if (!atomic_dec_and_test(&s->sc_count))
+ return;
+ idr_remove(&clp->cl_stateids, s->sc_stateid.si_opaque.so_id);
+ s->sc_free(s);
}
static void nfs4_put_deleg_lease(struct nfs4_file *fp)
@@ -689,7 +698,7 @@
spin_lock(&state_lock);
unhash_delegation_locked(dp);
spin_unlock(&state_lock);
- nfs4_put_delegation(dp);
+ nfs4_put_stid(&dp->dl_stid);
}
static void revoke_delegation(struct nfs4_delegation *dp)
@@ -699,7 +708,7 @@
WARN_ON(!list_empty(&dp->dl_recall_lru));
if (clp->cl_minorversion == 0)
- nfs4_put_delegation(dp);
+ nfs4_put_stid(&dp->dl_stid);
else {
dp->dl_stid.sc_type = NFS4_REVOKED_DELEG_STID;
spin_lock(&clp->cl_lock);
@@ -885,17 +894,14 @@
list_del(&stp->st_perstateowner);
}
-static void close_generic_stateid(struct nfs4_ol_stateid *stp)
+static void nfs4_free_ol_stateid(struct nfs4_stid *stid)
{
- release_all_access(stp);
-}
+ struct nfs4_ol_stateid *stp = openlockstateid(stid);
-static void free_generic_stateid(struct nfs4_ol_stateid *stp)
-{
+ release_all_access(stp);
if (stp->st_file)
put_nfs4_file(stp->st_file);
- remove_stid(&stp->st_stid);
- nfs4_free_stid(stateid_slab, &stp->st_stid);
+ kmem_cache_free(stateid_slab, stid);
}
static void __release_lock_stateid(struct nfs4_ol_stateid *stp)
@@ -908,8 +914,7 @@
file = find_any_file(stp->st_file);
if (file)
filp_close(file, (fl_owner_t)lockowner(stp->st_stateowner));
- close_generic_stateid(stp);
- free_generic_stateid(stp);
+ nfs4_put_stid(&stp->st_stid);
}
static void unhash_lockowner(struct nfs4_lockowner *lo)
@@ -966,13 +971,12 @@
{
unhash_generic_stateid(stp);
release_open_stateid_locks(stp);
- close_generic_stateid(stp);
}
static void release_open_stateid(struct nfs4_ol_stateid *stp)
{
unhash_open_stateid(stp);
- free_generic_stateid(stp);
+ nfs4_put_stid(&stp->st_stid);
}
static void unhash_openowner(struct nfs4_openowner *oo)
@@ -993,7 +997,7 @@
struct nfs4_ol_stateid *s = oo->oo_last_closed_stid;
if (s) {
- free_generic_stateid(s);
+ nfs4_put_stid(&s->st_stid);
oo->oo_last_closed_stid = NULL;
}
}
@@ -1467,12 +1471,12 @@
while (!list_empty(&reaplist)) {
dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru);
list_del_init(&dp->dl_recall_lru);
- nfs4_put_delegation(dp);
+ nfs4_put_stid(&dp->dl_stid);
}
while (!list_empty(&clp->cl_revoked)) {
dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru);
list_del_init(&dp->dl_recall_lru);
- nfs4_put_delegation(dp);
+ nfs4_put_stid(&dp->dl_stid);
}
while (!list_empty(&clp->cl_openowners)) {
oo = list_entry(clp->cl_openowners.next, struct nfs4_openowner, oo_perclient);
@@ -3588,7 +3592,7 @@
spin_unlock(&state_lock);
out:
if (status) {
- nfs4_put_delegation(dp);
+ nfs4_put_stid(&dp->dl_stid);
return ERR_PTR(status);
}
return dp;
@@ -3818,7 +3822,7 @@
if (open->op_file)
nfsd4_free_file(open->op_file);
if (open->op_stp)
- free_generic_stateid(open->op_stp);
+ nfs4_put_stid(&open->op_stp->st_stid);
}
__be32
@@ -4266,7 +4270,7 @@
spin_lock(&cl->cl_lock);
list_del_init(&dp->dl_recall_lru);
spin_unlock(&cl->cl_lock);
- nfs4_put_delegation(dp);
+ nfs4_put_stid(s);
ret = nfs_ok;
break;
default:
@@ -4477,19 +4481,22 @@
unhash_open_stateid(s);
if (clp->cl_minorversion) {
- free_generic_stateid(s);
if (list_empty(&oo->oo_owner.so_stateids))
release_openowner(oo);
+ nfs4_put_stid(&s->st_stid);
} else {
+ /*
+ * In the 4.0 case we need to keep the owners around a
+ * little while to handle CLOSE replay. We still do need
+ * to release any file access that is held by them
+ * before returning however.
+ */
+ release_all_access(s);
if (s->st_file) {
put_nfs4_file(s->st_file);
s->st_file = NULL;
}
oo->oo_last_closed_stid = s;
- /*
- * In the 4.0 case we need to keep the owners around a
- * little while to handle CLOSE replay.
- */
if (list_empty(&oo->oo_owner.so_stateids))
move_to_close_lru(oo, clp->net);
}
@@ -5665,7 +5672,7 @@
list_for_each_safe(pos, next, &reaplist) {
dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
list_del_init(&dp->dl_recall_lru);
- nfs4_put_delegation(dp);
+ nfs4_put_stid(&dp->dl_stid);
}
nfsd4_client_tracking_exit(net);