1 files changed, 11 insertions, 7 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 9c912c004247..b421b51c3a9e 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -342,7 +342,7 @@ find_any_file(struct nfs4_file *f)
         return ret;
 }
 
-static int num_delegations;
+static atomic_long_t num_delegations;
 unsigned long max_delegations;
 
 /*
@@ -582,22 +582,23 @@ static struct nfs4_delegation *
 alloc_init_deleg(struct nfs4_client *clp, struct nfs4_ol_stateid *stp, struct svc_fh *current_fh)
 {
         struct nfs4_delegation *dp;
+        long n;
 
         dprintk("NFSD alloc_init_deleg\n");
-        if (num_delegations > max_delegations)
-                return NULL;
+        n = atomic_long_inc_return(&num_delegations);
+        if (n < 0 || n > max_delegations)
+                goto out_dec;
         if (delegation_blocked(&current_fh->fh_handle))
-                return NULL;
+                goto out_dec;
         dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab));
         if (dp == NULL)
-                return dp;
+                goto out_dec;
         /*
          * delegation seqid's are never incremented.  The 4.1 special
          * meaning of seqid 0 isn't meaningful, really, but let's avoid
          * 0 anyway just for consistency and use 1:
          */
         dp->dl_stid.sc_stateid.si_generation = 1;
-        num_delegations++;
         INIT_LIST_HEAD(&dp->dl_perfile);
         INIT_LIST_HEAD(&dp->dl_perclnt);
         INIT_LIST_HEAD(&dp->dl_recall_lru);
@@ -605,6 +606,9 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_ol_stateid *stp, struct sv
         fh_copy_shallow(&dp->dl_fh, &current_fh->fh_handle);
         INIT_WORK(&dp->dl_recall.cb_work, nfsd4_run_cb_recall);
         return dp;
+out_dec:
+        atomic_long_dec(&num_delegations);
+        return NULL;
 }
 
 static void remove_stid(struct nfs4_stid *s)
@@ -627,7 +631,7 @@ nfs4_put_delegation(struct nfs4_delegation *dp)
                         put_nfs4_file(dp->dl_file);
                 remove_stid(&dp->dl_stid);
                 nfs4_free_stid(deleg_slab, &dp->dl_stid);
-                num_delegations--;
+                atomic_long_dec(&num_delegations);
         }
 }