linux-stable.git/fs/dlm, branch v6.6.2

fs: dlm: Simplify buffer size computation in dlm_create_debug_file()

2023-11-20T10:59:37+00:00

[ Upstream commit 19b3102c0b5350621e7492281f2be0f071fb7e31 ]

Use sizeof(name) instead of the equivalent, but hard coded,
DLM_LOCKSPACE_LEN + 8.

This is less verbose and more future proof.

Signed-off-by: Christophe JAILLET 
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland 
Signed-off-by: Sasha Levin

dlm: fix no ack after final message

2023-11-20T10:59:21+00:00

[ Upstream commit 6212e4528b248a4bc9b4fe68e029a84689c67461 ]

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 
Signed-off-by: Sasha Levin

dlm: be sure we reset all nodes at forced shutdown

2023-11-20T10:59:21+00:00

[ Upstream commit e759eb3e27e5b624930548f1c0eda90da6e26ee9 ]

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 
Signed-off-by: Sasha Levin

dlm: fix remove member after close call

2023-11-20T10:59:21+00:00

[ Upstream commit 2776635edc7fcd62e03cb2efb93c31f685887460 ]

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 
Signed-off-by: Sasha Levin

dlm: fix creating multiple node structures

2023-11-20T10:59:21+00:00

[ Upstream commit fe9b619e6e94acf0b068fb1a8f658f5a96b8fad7 ]

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 
Signed-off-by: Sasha Levin

fs: dlm: Fix the size of a buffer in dlm_create_debug_file()

2023-11-20T10:59:20+00:00

[ Upstream commit b859e01054354033f480d9df41b0ebc2c7537379 ]

8 is not the maximum size of the suffix used when creating debugfs files.

Let the compiler compute the correct size, and only give a hint about the
longest possible string that is used.

When building with W=1, this fixes the following warnings:

  fs/dlm/debug_fs.c: In function ‘dlm_create_debug_file’:
  fs/dlm/debug_fs.c:1020:58: error: ‘snprintf’ output may be truncated before the last format character [-Werror=format-truncation=]
   1020 |         snprintf(name, DLM_LOCKSPACE_LEN + 8, "%s_waiters", ls->ls_name);
        |                                                          ^
  fs/dlm/debug_fs.c:1020:9: note: ‘snprintf’ output between 9 and 73 bytes into a destination of size 72
   1020 |         snprintf(name, DLM_LOCKSPACE_LEN + 8, "%s_waiters", ls->ls_name);
        |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  fs/dlm/debug_fs.c:1031:50: error: ‘_queued_asts’ directive output may be truncated writing 12 bytes into a region of size between 8 and 72 [-Werror=format-truncation=]
   1031 |         snprintf(name, DLM_LOCKSPACE_LEN + 8, "%s_queued_asts", ls->ls_name);
        |                                                  ^~~~~~~~~~~~
  fs/dlm/debug_fs.c:1031:9: note: ‘snprintf’ output between 13 and 77 bytes into a destination of size 72
   1031 |         snprintf(name, DLM_LOCKSPACE_LEN + 8, "%s_queued_asts", ls->ls_name);
        |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 541adb0d4d10b ("fs: dlm: debugfs for queued callbacks")
Signed-off-by: Christophe JAILLET 
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland 
Signed-off-by: Sasha Levin

dlm: fix plock lookup when using multiple lockspaces

2023-08-25T15:31:39+00:00

All posix lock ops, for all lockspaces (gfs2 file systems) are
sent to userspace (dlm_controld) through a single misc device.
The dlm_controld daemon reads the ops from the misc device
and sends them to other cluster nodes using separate, per-lockspace
cluster api communication channels.  The ops for a single lockspace
are ordered at this level, so that the results are received in
the same sequence that the requests were sent.  When the results
are sent back to the kernel via the misc device, they are again
funneled through the single misc device for all lockspaces.  When
the dlm code in the kernel processes the results from the misc
device, these results will be returned in the same sequence that
the requests were sent, on a per-lockspace basis.  A recent change
in this request/reply matching code missed the "per-lockspace"
check (fsid comparison) when matching request and reply, so replies
could be incorrectly matched to requests from other lockspaces.

Cc: stable@vger.kernel.org
Reported-by: Barry Marson 
Fixes: 57e2c2f2d94c ("fs: dlm: fix mismatch of plock results from userspace")
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

fs: dlm: don't use RCOM_NAMES for version detection

2023-08-10T15:33:03+00:00

Currently RCOM_STATUS and RCOM_NAMES inclusive their replies are being
used to determine the DLM version. The RCOM_NAMES messages are triggered
in DLM recovery when calling dlm_recover_directory() only. At this time
the DLM version need to be determined. I ran some tests and did not
expirenced some issues. When the DLM version detection was developed
probably I run once in a case of RCOM_NAMES and the version was not
detected yet. However it seems to be not necessary.

For backwards compatibility we still need to accept RCOM_NAMES messages
which are not protected regarding the DLM message reliability layer aka
stateless message. This patch changes that RCOM_NAMES we are sending out
after this patch are not stateless anymore.

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

fs: dlm: create midcomms nodes when configure

2023-08-10T15:33:03+00:00

This patch puts the life of a midcomms node the same as a lowcomms
connection. The lowcomms connection lifetime was changed by commit
6f0b0b5d7ae7 ("fs: dlm: remove dlm_node_addrs lookup list"). In the
future the midcomms node instances can be merged with lowcomms
connection structure as the lifetime is the same and states can be
controlled over values or flags.

Before midcomms nodes were generated during version detection. This is
not necessary anymore when the nodes are created when the cluster
manager configures DLM via configfs. When a midcomms node is created over
configfs it well set DLM_VERSION_NOT_SET as version. This indicates that
the version of the midcomms node is still unknown and need to be probed
via certain rcom messages.

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

fs: dlm: constify receive buffer

2023-08-10T15:33:03+00:00

The dlm receive buffer should be never manipulated as DLM is the last
instance of parsing layer. This patch constify the whole receive buffer
so we are sure it never gets manipulated when it's being parsed.

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