linux.git/fs/dlm, branch v6.8

dlm: update format header reflect current format

2023-12-20T21:36:48+00:00

Over the time the dlm debugfs format string has been changed but the
header wasn't updated. This patch changes the first line dump header and
their meaning to reflect the current formats.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

dlm: fix format seq ops type 4

2023-12-20T21:36:48+00:00

This patch fixes to set the type 4 format ops in case of table_open4().
It got accidentially changed by commit 541adb0d4d10 ("fs: dlm: debugfs
for queued callbacks") and since them toss debug dumps the same format
as format 5 that are the queued ast callbacks for lkbs.

Fixes: 541adb0d4d10 ("fs: dlm: debugfs for queued callbacks")
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

dlm: use FL_SLEEP to determine blocking vs non-blocking

2023-11-16T17:59:19+00:00

This patch uses the FL_SLEEP flag in struct file_lock to determine if
the lock request is a blocking or non-blocking request. Before dlm was
using IS_SETLKW() was being used which is not usable for lock requests
coming from lockd when EXPORT_OP_SAFE_ASYNC_LOCK inside the export flags
is set.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

dlm: use fl_owner from lockd

2023-11-16T17:59:19+00:00

This patch is changing the fl_owner value in case of an nfs lock request
to not be the pid of lockd. Instead this patch changes it to be the
owner value that nfs is giving us.

Currently there exists proved problems with this behaviour. One nfsd
server was created to export a gfs2 filesystem mount. Two nfs clients
doing a nfs mount of this export. Those two clients should conflict each
other operating on the same nfs file.

A small test program was written:

int main(int argc, const char *argv[])
{
	struct flock fl = {
		.l_type = F_WRLCK,
		.l_whence = SEEK_SET,
		.l_start = 1L,
		.l_len = 1L,
	};
	int fd;

	fd = open("filename", O_RDWR | O_CREAT, 0700);
	printf("try to lock...\n");
	fcntl(fd, F_SETLKW, &fl);
	printf("locked!\n");
	getc(stdin);

	return 0;
}

Running on both clients at the same time and don't interrupting by
pressing any key. It will show that both clients are able to acquire the
lock which shouldn't be the case. The issue is here that the fl_owner
value is the same and the lock context of both clients should be
separated.

This patch lets lockd define how to deal with lock contexts and chose
hopefully the right fl_owner value. A test after this patch was made and
the locks conflicts each other which should be the case.

Acked-by: Jeff Layton 
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

dlm: use kernel_connect() and kernel_bind()

2023-11-16T17:58:42+00:00

Recent changes to kernel_connect() and kernel_bind() ensure that
callers are insulated from changes to the address parameter made by BPF
SOCK_ADDR hooks. This patch wraps direct calls to ops->connect() and
ops->bind() with kernel_connect() and kernel_bind() to protect callers
in such cases.

Link: https://lore.kernel.org/netdev/9944248dba1bce861375fcce9de663934d933ba9.camel@redhat.com/
Fixes: d74bad4e74ee ("bpf: Hooks for sys_connect")
Fixes: 4fbac77d2d09 ("bpf: Hooks for sys_bind")
Cc: stable@vger.kernel.org
Signed-off-by: Jordan Rife 
Signed-off-by: David Teigland

dlm: slow down filling up processing queue

2023-10-12T20:21:00+00:00

If there is a burst of message the receive worker will filling up the
processing queue but where are too slow to process dlm messages. This
patch will slow down the receiver worker to keep the buffer on the
socket layer to tell the sender to backoff. This is done by a threshold
to get the next buffers from the socket after all messages were
processed done by a flush_workqueue(). This however only occurs when we
have a message burst when we e.g. create 1 million locks. If we put more
and more new messages to process in the processqueue we will soon run out
of memory.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

dlm: fix no ack after final message

2023-10-12T20:20:55+00:00

In case of an final DLM message we can't should not send an ack out
after the final message. This patch moves the ack message before the
messages will be transmitted. If it's the final message and the
receiving node turns into DLM_CLOSED state another ack messages will
being received and turning the receiving node into DLM_ESTABLISHED
again.

Fixes: 1696c75f1864 ("fs: dlm: add send ack threshold and append acks to msgs")
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

dlm: be sure we reset all nodes at forced shutdown

2023-10-12T20:20:48+00:00

In case we running in a force shutdown in either midcomms or lowcomms
implementation we will make sure we reset all per midcomms node
information.

Fixes: 63e711b08160 ("fs: dlm: create midcomms nodes when configure")
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

dlm: fix remove member after close call

2023-10-12T20:20:37+00:00

The idea of commit 63e711b08160 ("fs: dlm: create midcomms nodes when
configure") is to set the midcomms node lifetime when a node joins or
leaves the cluster. Currently we can hit the following warning:

[10844.611495] ------------[ cut here ]------------
[10844.615913] WARNING: CPU: 4 PID: 84304 at fs/dlm/midcomms.c:1263
dlm_midcomms_remove_member+0x13f/0x180 [dlm]

or running in a state where we hit a midcomms node usage count in a
negative value:

[  260.830782] node 2 users dec count -1

The first warning happens when the a specific node does not exists and
it was probably removed but dlm_midcomms_close() which is called when a
node leaves the cluster. The second kernel log message is probably in a
case when dlm_midcomms_addr() is called when a joined the cluster but
due fencing a node leaved the cluster without getting removed from the
lockspace. If the node joins the cluster and it was removed from the
cluster due fencing the first call is to remove the node from lockspaces
triggered by the user space. In both cases if the node wasn't found or
the user count is zero, we should ignore any additional midcomms handling
of dlm_midcomms_remove_member().

Fixes: 63e711b08160 ("fs: dlm: create midcomms nodes when configure")
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

dlm: fix creating multiple node structures

2023-10-12T20:20:28+00:00

This patch will lookup existing nodes instead of always creating them
when dlm_midcomms_addr() is called. The idea is here to create midcomms
nodes when user space getting informed that nodes joins the cluster. This
is the case when dlm_midcomms_addr() is called, however it can be called
multiple times by user space to add several address configurations to one
node e.g. when using SCTP. Those multiple times need to be filtered out
and we doing that by looking up if the node exists before. Due configfs
entry it is safe that this function gets only called once at a time.

Fixes: 63e711b08160 ("fs: dlm: create midcomms nodes when configure")
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland