diff options
| -rw-r--r-- | fs/nfs/delegation.c | 42 |
1 files changed, 28 insertions, 14 deletions
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index 15671245c6ee..8d9ec494a944 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -129,21 +129,35 @@ again: */ void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res) { - struct nfs_delegation *delegation = NFS_I(inode)->delegation; - struct rpc_cred *oldcred; + struct nfs_delegation *delegation; + struct rpc_cred *oldcred = NULL; - if (delegation == NULL) - return; - memcpy(delegation->stateid.data, res->delegation.data, - sizeof(delegation->stateid.data)); - delegation->type = res->delegation_type; - delegation->maxsize = res->maxsize; - oldcred = delegation->cred; - delegation->cred = get_rpccred(cred); - clear_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags); - NFS_I(inode)->delegation_state = delegation->type; - smp_wmb(); - put_rpccred(oldcred); + rcu_read_lock(); + delegation = rcu_dereference(NFS_I(inode)->delegation); + if (delegation != NULL) { + spin_lock(&delegation->lock); + if (delegation->inode != NULL) { + memcpy(delegation->stateid.data, res->delegation.data, + sizeof(delegation->stateid.data)); + delegation->type = res->delegation_type; + delegation->maxsize = res->maxsize; + oldcred = delegation->cred; + delegation->cred = get_rpccred(cred); + clear_bit(NFS_DELEGATION_NEED_RECLAIM, + &delegation->flags); + NFS_I(inode)->delegation_state = delegation->type; + spin_unlock(&delegation->lock); + put_rpccred(oldcred); + rcu_read_unlock(); + } else { + /* We appear to have raced with a delegation return. */ + spin_unlock(&delegation->lock); + rcu_read_unlock(); + nfs_inode_set_delegation(inode, cred, res); + } + } else { + rcu_read_unlock(); + } } static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync) |