kernel.git/fs/dlm/midcomms.c, branch linux-6.4.y

fs: dlm: revert check required context while close

2023-07-23T11:53:57Z

commit c6b6d6dcc7f32767d57740e0552337c8de40610b upstream. This patch reverts commit 2c3fa6ae4d52 ("dlm: check required context while close"). The function dlm_midcomms_close(), which will call later dlm_lowcomms_close(), is called when the cluster manager tells the node got fenced which means on midcomms/lowcomms layer to disconnect the node from the cluster communication. The node can rejoin the cluster later. This patch was ensuring no new message were able to be triggered when we are in the close() function context. This was done by checking if the lockspace has been stopped. However there is a missing check that we only need to check specific lockspaces where the fenced node is member of. This is currently complicated because there is no way to easily check if a node is part of a specific lockspace without stopping the recovery. For now we just revert this commit as it is just a check to finding possible leaks of stopping lockspaces before close() is called. Cc: stable@vger.kernel.org Fixes: 2c3fa6ae4d52 ("dlm: check required context while close") Signed-off-by: Alexander Aring Signed-off-by: David Teigland Signed-off-by: Greg Kroah-Hartman

fs: dlm: remove unnecessary waker_up() calls

2023-01-23T22:27:28Z

The wake_up() is already handled inside of midcomms_node_reset() when switching the state to CLOSED state. So there is not need to call it after midcomms_node_reset() again. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: move state change into else branch

2023-01-23T22:27:27Z

Currently we can switch at first into DLM_CLOSE_WAIT state and then do another state change if a condition is true. Instead of doing two state changes we handle the other state change inside an else branch of this condition. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: remove newline in log_print

2023-01-23T22:27:26Z

There is an API difference between log_print() and other printk()s to put a newline or not. This one was introduced by mistake because log_print() adds a newline. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: reduce the shutdown timeout to 5 secs

2023-01-23T22:27:20Z

When a shutdown is stuck, time out after 5 seconds instead of 3 minutes. After this timeout we try a forced shutdown. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: wait until all midcomms nodes detect version

2023-01-23T20:58:19Z

The current dlm version detection is very complex due to backwards compatablilty with earlier dlm protocol versions. It takes some time to detect if a peer node has a specific DLM version. If it's not detected, we just cut the socket connection. There could be cases where the local node has not detected the version yet, but the peer node has. In these cases, we are trying to shutdown the dlm connection with a FIN/ACK message exchange to be sure the other peer is ready to shutdown the connection on dlm application level. However this mechanism is only available on DLM protocol version 3.2 and we need to be sure the DLM version is detected before. To make it more robust we introduce a a "best effort" wait to wait for the version detection before shutdown the dlm connection. This need to be done before the kthread recoverd for recovery handling is stopped, because recovery handling will trigger enough messages to have a version detection going on. It is a corner case which was detected by modprobe dlm_locktroture module and rmmod dlm_locktorture module directly afterwards (in a looping behaviour). In practice probably nobody would leave a lockspace immediately after joining it. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: ignore unexpected non dlm opts msgs

2023-01-23T20:42:02Z

This patch ignores unexpected RCOM_NAMES/RCOM_STATUS messages. To be backwards compatible, those messages are not part of the new reliable DLM OPTS encapsulation header, and have their own retransmit handling using sequence number matching When we get unexpected non dlm opts messages, we should allow them and let RCOM message handling filter them out using sequence numbers. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: bring back previous shutdown handling

2023-01-23T20:36:37Z

This patch mostly reverts commit 4f567acb0b86 ("fs: dlm: remove socket shutdown handling"). There can be situations where the dlm midcomms nodes hash and lowcomms connection hash are not equal, but we need to guarantee that the lowcomms are all closed on a last release of a dlm lockspace, when a shutdown is invoked. This patch guarantees that we always close all sockets managed by the lowcomms connection hash, and calls shutdown for the last message sent. This ensures we don't cut the socket, which could cause the peer to get a connection reset. In future we should try to merge the midcomms/lowcomms hashes into one hash and not handle both in separate hashes. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: send FIN ack back in right cases

2023-01-23T20:30:07Z

This patch moves to send a ack back for receiving a FIN message only when we are in valid states. In other cases and there might be a sender waiting for a ack we just let it timeout at the senders time and hopefully all other cleanups will remove the FIN message on their sending queue. As an example we should never send out an ACK being in LAST_ACK state or we cannot assume a working socket communication when we are in CLOSED state. Cc: stable@vger.kernel.org Fixes: 489d8e559c65 ("fs: dlm: add reliable connection if reconnect") Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: move sending fin message into state change handling

2023-01-23T20:30:06Z

This patch moves the send fin handling, which should appear in a specific state change, into the state change handling while the per node state_lock is held. I experienced issues with other messages because we changed the state and a fin message was sent out in a different state. Cc: stable@vger.kernel.org Fixes: 489d8e559c65 ("fs: dlm: add reliable connection if reconnect") Signed-off-by: Alexander Aring Signed-off-by: David Teigland