nfs: track whether server sets MAY_NOTIFY_LOCK flag

We want to handle the two cases differently, such that we poll more
aggressively when we don't expect a callback.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

2 files changed, 3 insertions, 0 deletions

diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 804113421337..55cfeadedb6e 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -157,6 +157,7 @@ enum {
         NFS_STATE_RECLAIM_NOGRACE,      /* OPEN stateid needs to recover state */
         NFS_STATE_POSIX_LOCKS,          /* Posix locks are supported */
         NFS_STATE_RECOVERY_FAILED,      /* OPEN stateid state recovery failed */
+        NFS_STATE_MAY_NOTIFY_LOCK,      /* server may CB_NOTIFY_LOCK */
 };
 
 struct nfs4_state {
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 0aac0fbf0b58..93cf38e8098a 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2537,6 +2537,8 @@ static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata,
                 goto out;
         if (server->caps & NFS_CAP_POSIX_LOCK)
                 set_bit(NFS_STATE_POSIX_LOCKS, &state->flags);
+        if (opendata->o_res.rflags & NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK)
+                set_bit(NFS_STATE_MAY_NOTIFY_LOCK, &state->flags);
 
         dentry = opendata->dentry;
         if (d_really_is_negative(dentry)) {