diff options
| -rw-r--r-- | fs/nfs/localio.c | 11 | ||||
| -rw-r--r-- | fs/nfs_common/nfslocalio.c | 39 |
2 files changed, 20 insertions, 30 deletions
diff --git a/fs/nfs/localio.c b/fs/nfs/localio.c index a4bacd9a5052..7a33da477da3 100644 --- a/fs/nfs/localio.c +++ b/fs/nfs/localio.c @@ -282,14 +282,9 @@ nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred, return NULL; rcu_read_lock(); /* try to swap in the pointer */ - spin_lock(&clp->cl_uuid.lock); - nf = rcu_dereference_protected(*pnf, 1); - if (!nf) { - nf = new; - new = NULL; - rcu_assign_pointer(*pnf, nf); - } - spin_unlock(&clp->cl_uuid.lock); + nf = unrcu_pointer(cmpxchg(pnf, NULL, RCU_INITIALIZER(new))); + if (!nf) + swap(nf, new); } nf = nfs_local_file_get(nf); rcu_read_unlock(); diff --git a/fs/nfs_common/nfslocalio.c b/fs/nfs_common/nfslocalio.c index 6a0bdea6d644..bdf251332b6b 100644 --- a/fs/nfs_common/nfslocalio.c +++ b/fs/nfs_common/nfslocalio.c @@ -273,8 +273,8 @@ EXPORT_SYMBOL_GPL(nfs_open_local_fh); void nfs_close_local_fh(struct nfs_file_localio *nfl) { - struct nfsd_file *ro_nf = NULL; - struct nfsd_file *rw_nf = NULL; + struct nfsd_file *ro_nf; + struct nfsd_file *rw_nf; nfs_uuid_t *nfs_uuid; rcu_read_lock(); @@ -285,28 +285,23 @@ void nfs_close_local_fh(struct nfs_file_localio *nfl) return; } - ro_nf = rcu_access_pointer(nfl->ro_file); - rw_nf = rcu_access_pointer(nfl->rw_file); - if (ro_nf || rw_nf) { - spin_lock(&nfs_uuid->lock); - if (ro_nf) - ro_nf = rcu_dereference_protected(xchg(&nfl->ro_file, NULL), 1); - if (rw_nf) - rw_nf = rcu_dereference_protected(xchg(&nfl->rw_file, NULL), 1); - - /* Remove nfl from nfs_uuid->files list */ - RCU_INIT_POINTER(nfl->nfs_uuid, NULL); - list_del_init(&nfl->list); - spin_unlock(&nfs_uuid->lock); - rcu_read_unlock(); + ro_nf = unrcu_pointer(xchg(&nfl->ro_file, NULL)); + rw_nf = unrcu_pointer(xchg(&nfl->rw_file, NULL)); - if (ro_nf) - nfs_to_nfsd_file_put_local(ro_nf); - if (rw_nf) - nfs_to_nfsd_file_put_local(rw_nf); - return; - } + spin_lock(&nfs_uuid->lock); + /* Remove nfl from nfs_uuid->files list */ + list_del_init(&nfl->list); + spin_unlock(&nfs_uuid->lock); rcu_read_unlock(); + /* Now we can allow racing nfs_close_local_fh() to + * skip the locking. + */ + RCU_INIT_POINTER(nfl->nfs_uuid, NULL); + + if (ro_nf) + nfs_to_nfsd_file_put_local(ro_nf); + if (rw_nf) + nfs_to_nfsd_file_put_local(rw_nf); } EXPORT_SYMBOL_GPL(nfs_close_local_fh); |