[PATCH 4.9 12/69] CIFS: reconnect thread reschedule itself

From: Greg Kroah-Hartman
Date: Wed Apr 19 2017 - 11:16:57 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Germano Percossi <germano.percossi@xxxxxxxxxx>

commit 18ea43113f5b74a97dd4be9bddbac10d68b1a6ce upstream.

In case of error, smb2_reconnect_server reschedule itself
with a delay, to avoid being too aggressive.

Signed-off-by: Germano Percossi <germano.percossi@xxxxxxxxxx>
Reviewed-by: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/cifs/smb2pdu.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1987,6 +1987,9 @@ void smb2_reconnect_server(struct work_s
struct cifs_tcon *tcon, *tcon2;
struct list_head tmp_list;
int tcon_exist = false;
+ int rc;
+ int resched = false;
+

/* Prevent simultaneous reconnects that can corrupt tcon->rlist list */
mutex_lock(&server->reconnect_mutex);
@@ -2014,13 +2017,18 @@ void smb2_reconnect_server(struct work_s
spin_unlock(&cifs_tcp_ses_lock);

list_for_each_entry_safe(tcon, tcon2, &tmp_list, rlist) {
- if (!smb2_reconnect(SMB2_INTERNAL_CMD, tcon))
+ rc = smb2_reconnect(SMB2_INTERNAL_CMD, tcon);
+ if (!rc)
cifs_reopen_persistent_handles(tcon);
+ else
+ resched = true;
list_del_init(&tcon->rlist);
cifs_put_tcon(tcon);
}

cifs_dbg(FYI, "Reconnecting tcons finished\n");
+ if (resched)
+ queue_delayed_work(cifsiod_wq, &server->reconnect, 2 * HZ);
mutex_unlock(&server->reconnect_mutex);

/* now we can safely release srv struct */