Commit 82334252 authored by Shyam Prasad N's avatar Shyam Prasad N Committed by Steve French
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Revert "cifs: reconnect work should have reference on server struct" 



This reverts commit 19a4b9d6.

This earlier commit was making an assumption that each mod_delayed_work
called for the reconnect work would result in smb2_reconnect_server
being called twice. This assumption turns out to be untrue. So reverting
this change for now.

I will submit a follow-up patch to fix the actual problem in a different
way.

Signed-off-by: default avatarShyam Prasad N <sprasad@microsoft.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 691a41d8

fs/smb/client/connect.c

+6 −21
Original line number Diff line number Diff line
@@ -402,13 +402,7 @@ static int __cifs_reconnect(struct TCP_Server_Info *server, 
			spin_unlock(&server->srv_lock);

			cifs_swn_reset_server_dstaddr(server);

			cifs_server_unlock(server);



			/* increase ref count which reconnect work will drop */

			spin_lock(&cifs_tcp_ses_lock);

			server->srv_count++;

			spin_unlock(&cifs_tcp_ses_lock);

			if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0))

				cifs_put_tcp_session(server, false);

			mod_delayed_work(cifsiod_wq, &server->reconnect, 0);

		}

	} while (server->tcpStatus == CifsNeedReconnect);
@@ -538,13 +532,7 @@ static int reconnect_dfs_server(struct TCP_Server_Info *server) 
		spin_unlock(&server->srv_lock);

		cifs_swn_reset_server_dstaddr(server);

		cifs_server_unlock(server);



		/* increase ref count which reconnect work will drop */

		spin_lock(&cifs_tcp_ses_lock);

		server->srv_count++;

		spin_unlock(&cifs_tcp_ses_lock);

		if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0))

			cifs_put_tcp_session(server, false);

		mod_delayed_work(cifsiod_wq, &server->reconnect, 0);

	} while (server->tcpStatus == CifsNeedReconnect);



	mutex_lock(&server->refpath_lock);
@@ -1626,19 +1614,16 @@ cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect) 


	cancel_delayed_work_sync(&server->echo);



	if (from_reconnect) {

	if (from_reconnect)

		/*

		 * Avoid deadlock here: reconnect work calls

		 * cifs_put_tcp_session() at its end. Need to be sure

		 * that reconnect work does nothing with server pointer after

		 * that step.

		 */

		if (cancel_delayed_work(&server->reconnect))

			cifs_put_tcp_session(server, from_reconnect);

	} else {

		if (cancel_delayed_work_sync(&server->reconnect))

			cifs_put_tcp_session(server, from_reconnect);

	}

		cancel_delayed_work(&server->reconnect);

	else

		cancel_delayed_work_sync(&server->reconnect);



	spin_lock(&server->srv_lock);

	server->tcpStatus = CifsExiting;

fs/smb/client/smb2pdu.c

+10 −13
Original line number Diff line number Diff line
@@ -3952,6 +3952,12 @@ void smb2_reconnect_server(struct work_struct *work) 
		}

		spin_unlock(&ses->chan_lock);

	}

	/*

	 * Get the reference to server struct to be sure that the last call of

	 * cifs_put_tcon() in the loop below won't release the server pointer.

	 */

	if (tcon_exist || ses_exist)

		server->srv_count++;



	spin_unlock(&cifs_tcp_ses_lock);
@@ -3999,17 +4005,13 @@ void smb2_reconnect_server(struct work_struct *work) 


done:

	cifs_dbg(FYI, "Reconnecting tcons and channels finished\n");

	if (resched) {

	if (resched)

		queue_delayed_work(cifsiod_wq, &server->reconnect, 2 * HZ);

	mutex_unlock(&pserver->reconnect_mutex);



		/* no need to put tcp session as we're retrying */

		return;

	}

	mutex_unlock(&pserver->reconnect_mutex);



	/* now we can safely release srv struct */

	cifs_put_tcp_session(server, true);

	if (tcon_exist || ses_exist)

		cifs_put_tcp_session(server, 1);

}



int
@@ -4029,12 +4031,7 @@ SMB2_echo(struct TCP_Server_Info *server) 
	    server->ops->need_neg(server)) {

		spin_unlock(&server->srv_lock);

		/* No need to send echo on newly established connections */

		spin_lock(&cifs_tcp_ses_lock);

		server->srv_count++;

		spin_unlock(&cifs_tcp_ses_lock);

		if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0))

			cifs_put_tcp_session(server, false);



		mod_delayed_work(cifsiod_wq, &server->reconnect, 0);

		return rc;

	}

	spin_unlock(&server->srv_lock);