Commit Graph

618 Commits

Author SHA1 Message Date
Alexander Aring
957adb68b3 fs: dlm: invalid buffer access in lookup error
This patch will evaluate the message length if a dlm opts header can fit
in before accessing it if a node lookup fails. The invalid sequence
error means that the version detection failed and an unexpected message
arrived. For debugging such situation the type of arrived message is
important to know.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-06-11 12:44:47 -05:00
Alexander Aring
f5fe8d5107 fs: dlm: fix race in mhandle deletion
This patch fixes a race between mhandle deletion in case of receiving an
acknowledge and flush of all pending mhandle in cases of an timeout or
resetting node states.

Fixes: 489d8e559c ("fs: dlm: add reliable connection if reconnect")
Reported-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-06-11 12:44:47 -05:00
Alexander Aring
d10a0b8875 fs: dlm: rename socket and app buffer defines
This patch renames DEFAULT_BUFFER_SIZE to DLM_MAX_SOCKET_BUFSIZE and
LOWCOMMS_MAX_TX_BUFFER_LEN to DLM_MAX_APP_BUFSIZE as they are proper
names to define what's behind those values. The DLM_MAX_SOCKET_BUFSIZE
defines the maximum size of buffer which can be handled on socket layer,
the DLM_MAX_APP_BUFSIZE defines the maximum size of buffer which can be
handled by the DLM application layer.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-06-02 11:53:04 -05:00
Alexander Aring
ac7d5d036d fs: dlm: introduce proto values
Currently the dlm protocol values are that TCP is 0 and everything else
is SCTP. This makes it difficult to introduce possible other transport
layers. The only one user space tool dlm_controld, which I am aware of,
handles the protocol value 1 for SCTP. We change it now to handle SCTP
as 1, this will break user space API but it will fix it so we can add
possible other transport layers.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-06-02 11:53:04 -05:00
Alexander Aring
9a4139a794 fs: dlm: move dlm allow conn
This patch checks if possible allowing new connections is allowed before
queueing the listen socket to accept new connections.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-06-02 11:53:04 -05:00
Alexander Aring
6c6a1cc666 fs: dlm: use alloc_ordered_workqueue
The proper way to allocate ordered workqueues is to use
alloc_ordered_workqueue() function. The current way implies an ordered
workqueue which is also required by dlm.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-06-02 11:53:04 -05:00
Alexander Aring
700ab1c363 fs: dlm: fix memory leak when fenced
I got some kmemleak report when a node was fenced. The user space tool
dlm_controld will therefore run some rmdir() in dlm configfs which was
triggering some memleaks. This patch stores the sps and cms attributes
which stores some handling for subdirectories of the configfs cluster
entry and free them if they get released as the parent directory gets
freed.

unreferenced object 0xffff88810d9e3e00 (size 192):
  comm "dlm_controld", pid 342, jiffies 4294698126 (age 55438.801s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 73 70 61 63 65 73 00 00  ........spaces..
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000db8b640b>] make_cluster+0x5d/0x360
    [<000000006a571db4>] configfs_mkdir+0x274/0x730
    [<00000000b094501c>] vfs_mkdir+0x27e/0x340
    [<0000000058b0adaf>] do_mkdirat+0xff/0x1b0
    [<00000000d1ffd156>] do_syscall_64+0x40/0x80
    [<00000000ab1408c8>] entry_SYSCALL_64_after_hwframe+0x44/0xae
unreferenced object 0xffff88810d9e3a00 (size 192):
  comm "dlm_controld", pid 342, jiffies 4294698126 (age 55438.801s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 63 6f 6d 6d 73 00 00 00  ........comms...
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000a7ef6ad2>] make_cluster+0x82/0x360
    [<000000006a571db4>] configfs_mkdir+0x274/0x730
    [<00000000b094501c>] vfs_mkdir+0x27e/0x340
    [<0000000058b0adaf>] do_mkdirat+0xff/0x1b0
    [<00000000d1ffd156>] do_syscall_64+0x40/0x80
    [<00000000ab1408c8>] entry_SYSCALL_64_after_hwframe+0x44/0xae

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-06-02 11:53:04 -05:00
Alexander Aring
fcef0e6c27 fs: dlm: fix lowcomms_start error case
This patch fixes the error path handling in lowcomms_start(). We need to
cleanup some static allocated data structure and cleanup possible
workqueue if these have started.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-06-02 11:53:04 -05:00
Colin Ian King
7d3848c03e fs: dlm: Fix spelling mistake "stucked" -> "stuck"
There are spelling mistake in log messages. Fix these.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-26 09:49:04 -05:00
Colin Ian King
f6089981d0 fs: dlm: Fix memory leak of object mh
There is an error return path that is not kfree'ing mh after
it has been successfully allocates.  Fix this by moving the
call to create_rcom to after the check on rc_in->rc_id check
to avoid this.

Thanks to Alexander Ahring Oder Aring for suggesting the
correct way to fix this.

Addresses-Coverity: ("Resource leak")
Fixes: a070a91cf1 ("fs: dlm: add more midcomms hooks")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-26 09:49:04 -05:00
Alexander Aring
706474fbc5 fs: dlm: don't allow half transmitted messages
This patch will clean a dirty page buffer if a reconnect occurs. If a page
buffer was half transmitted we cannot start inside the middle of a dlm
message if a node connects again. I observed invalid length receptions
errors and was guessing that this behaviour occurs, after this patch I
never saw an invalid message length again. This patch might drops more
messages for dlm version 3.1 but 3.1 can't deal with half messages as
well, for 3.2 it might trigger more re-transmissions but will not leave dlm
in a broken state.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
5b2f981fde fs: dlm: add midcomms debugfs functionality
This patch adds functionality to debug midcomms per connection state
inside a comms directory which is similar like dlm configfs. Currently
there exists the possibility to read out two attributes which is the
send queue counter and the version of each midcomms node state.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
489d8e559c fs: dlm: add reliable connection if reconnect
This patch introduce to make a tcp lowcomms connection reliable even if
reconnects occurs. This is done by an application layer re-transmission
handling and sequence numbers in dlm protocols. There are three new dlm
commands:

DLM_OPTS:

This will encapsulate an existing dlm message (and rcom message if they
don't have an own application side re-transmission handling). As optional
handling additional tlv's (type length fields) can be appended. This can
be for example a sequence number field. However because in DLM_OPTS the
lockspace field is unused and a sequence number is a mandatory field it
isn't made as a tlv and we put the sequence number inside the lockspace
id. The possibility to add optional options are still there for future
purposes.

DLM_ACK:

Just a dlm header to acknowledge the receive of a DLM_OPTS message to
it's sender.

DLM_FIN:

This provides a 4 way handshake for connection termination inclusive
support for half-closed connections. It's provided on application layer
because SCTP doesn't support half-closed sockets, the shutdown() call
can interrupted by e.g. TCP resets itself and a hard logic to implement
it because the othercon paradigm in lowcomms. The 4-way termination
handshake also solve problems to synchronize peer EOF arrival and that
the cluster manager removes the peer in the node membership handling of
DLM. In some cases messages can be still transmitted in this time and we
need to wait for the node membership event.

To provide a reliable connection the node will retransmit all
unacknowledges message to it's peer on reconnect. The receiver will then
filtering out the next received message and drop all messages which are
duplicates.

As RCOM_STATUS and RCOM_NAMES messages are the first messages which are
exchanged and they have they own re-transmission handling, there exists
logic that these messages must be first. If these messages arrives we
store the dlm version field. This handling is on DLM 3.1 and after this
patch 3.2 the same. A backwards compatibility handling has been added
which seems to work on tests without tcpkill, however it's not recommended
to use DLM 3.1 and 3.2 at the same time, because DLM 3.2 tries to fix long
term bugs in the DLM protocol.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
8e2e40860c fs: dlm: add union in dlm header for lockspace id
This patch adds union inside the lockspace id to handle it also for
another use case for a different dlm command.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
37a247da51 fs: dlm: move out some hash functionality
This patch moves out some lowcomms hash functionality into lowcomms
header to provide them to other layers like midcomms as well.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
2874d1a68c fs: dlm: add functionality to re-transmit a message
This patch introduces a retransmit functionality for a lowcomms message
handle. It's just allocates a new buffer and transmit it again, no
special handling about prioritize it because keeping bytestream in order.

To avoid another connection look some refactor was done to make a new
buffer allocation with a preexisting connection pointer.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
8f2dc78dbc fs: dlm: make buffer handling per msg
This patch makes the void pointer handle for lowcomms functionality per
message and not per page allocation entry. A refcount handling for the
handle was added to keep the message alive until the user doesn't need
it anymore.

There exists now a per message callback which will be called when
allocating a new buffer. This callback will be guaranteed to be called
according the order of the sending buffer, which can be used that the
caller increments a sequence number for the dlm message handle.

For transition process we cast the dlm_mhandle to dlm_msg and vice versa
until the midcomms layer will implement a specific dlm_mhandle structure.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
a070a91cf1 fs: dlm: add more midcomms hooks
This patch prepares hooks to redirect to the midcomms layer which will
be used by the midcomms re-transmit handling.

There exists the new concept of stateless buffers allocation and
commits. This can be used to bypass the midcomms re-transmit handling. It
is used by RCOM_STATUS and RCOM_NAMES messages, because they have their
own ping-like re-transmit handling. As well these two messages will be
used to determine the DLM version per node, because these two messages
are per observation the first messages which are exchanged.

Cluster manager events for node membership are added to add support for
half-closed connections in cases that the peer connection get to
an end of file but DLM still holds membership of the node. In
this time DLM can still trigger new message which we should allow. After
the cluster manager node removal event occurs it safe to close the
connection.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
6fb5cf9d42 fs: dlm: public header in out utility
This patch allows to use header_out() and header_in() outside of dlm
util functionality.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
8aa31cbf20 fs: dlm: fix connection tcp EOF handling
This patch fixes the EOF handling for TCP that if and EOF is received we
will close the socket next time the writequeue runs empty. This is a
half-closed socket functionality which doesn't exists in SCTP. The
midcomms layer will do a half closed socket functionality on DLM side to
solve this problem for the SCTP case. However there is still the last ack
flying around but other reset functionality will take care of it if it got
lost.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
c6aa00e3d2 fs: dlm: cancel work sync othercon
These rx tx flags arguments are for signaling close_connection() from
which worker they are called. Obviously the receive worker cannot cancel
itself and vice versa for swork. For the othercon the receive worker
should only be used, however to avoid deadlocks we should pass the same
flags as the original close_connection() was called.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
ba868d9dea fs: dlm: reconnect if socket error report occurs
This patch will change the reconnect handling that if an error occurs
if a socket error callback is occurred. This will also handle reconnects
in a non blocking connecting case which is currently missing. If error
ECONNREFUSED is reported we delay the reconnect by one second.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
7443bc9625 fs: dlm: set is othercon flag
There is a is othercon flag which is never used, this patch will set it
and printout a warning if the othercon ever sends a dlm message which
should never be the case.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
b38bc9c2b3 fs: dlm: fix srcu read lock usage
This patch holds the srcu connection read lock in cases where we lookup
the connections and accessing it. We don't hold the srcu lock in workers
function where the scheduled worker is part of the connection itself.
The connection should not be freed if any worker is scheduled or
pending.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
2df6b7627a fs: dlm: add dlm macros for ratelimit log
This patch add ratelimit macro to dlm subsystem and will set the
connecting log message to ratelimit. In non blocking connecting cases it
will print out this message a lot.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Alexander Aring
c937aabbd7 fs: dlm: always run complete for possible waiters
This patch changes the ping_members() result that we always run
complete() for possible waiters. We handle the -EINTR error code as
successful. This error code is returned if the recovery is stopped which
is likely that a new recovery is triggered with a new members
configuration and ping_members() runs again.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-05-25 09:22:20 -05:00
Yang Yingliang
2fd8db2dd0 fs: dlm: fix missing unlock on error in accept_from_sock()
Add the missing unlock before return from accept_from_sock()
in the error handling case.

Fixes: 6cde210a97 ("fs: dlm: add helper for init connection")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-29 13:28:18 -05:00
Alexander Aring
9d232469bc fs: dlm: add shutdown hook
This patch fixes issues which occurs when dlm lowcomms synchronize their
workqueues but dlm application layer already released the lockspace. In
such cases messages like:

dlm: gfs2: release_lockspace final free
dlm: invalid lockspace 3841231384 from 1 cmd 1 type 11

are printed on the kernel log. This patch is solving this issue by
introducing a new "shutdown" hook before calling "stop" hook when the
lockspace is going to be released finally. This should pretend any
dlm messages sitting in the workqueues during or after lockspace
removal.

It's necessary to call dlm_scand_stop() as I instrumented
dlm_lowcomms_get_buffer() code to report a warning after it's called after
dlm_midcomms_shutdown() functionality, see below:

WARNING: CPU: 1 PID: 3794 at fs/dlm/midcomms.c:1003 dlm_midcomms_get_buffer+0x167/0x180
Modules linked in: joydev iTCO_wdt intel_pmc_bxt iTCO_vendor_support drm_ttm_helper ttm pcspkr serio_raw i2c_i801 i2c_smbus drm_kms_helper virtio_scsi lpc_ich virtio_balloon virtio_console xhci_pci xhci_pci_renesas cec qemu_fw_cfg drm [last unloaded: qxl]
CPU: 1 PID: 3794 Comm: dlm_scand Tainted: G        W         5.11.0+ #26
Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.13.0-2.module+el8.3.0+7353+9de0a3cc 04/01/2014
RIP: 0010:dlm_midcomms_get_buffer+0x167/0x180
Code: 5d 41 5c 41 5d 41 5e 41 5f c3 0f 0b 45 31 e4 5b 5d 4c 89 e0 41 5c 41 5d 41 5e 41 5f c3 4c 89 e7 45 31 e4 e8 3b f1 ec ff eb 86 <0f> 0b 4c 89 e7 45 31 e4 e8 2c f1 ec ff e9 74 ff ff ff 0f 1f 80 00
RSP: 0018:ffffa81503f8fe60 EFLAGS: 00010202
RAX: 0000000000000008 RBX: ffff8f969827f200 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffffad1e89a0 RDI: ffff8f96a5294160
RBP: 0000000000000001 R08: 0000000000000000 R09: ffff8f96a250bc60
R10: 00000000000045d3 R11: 0000000000000000 R12: ffff8f96a250bc60
R13: ffffa81503f8fec8 R14: 0000000000000070 R15: 0000000000000c40
FS:  0000000000000000(0000) GS:ffff8f96fbc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055aa3351c000 CR3: 000000010bf22000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 dlm_scan_rsbs+0x420/0x670
 ? dlm_uevent+0x20/0x20
 dlm_scand+0xbf/0xe0
 kthread+0x13a/0x150
 ? __kthread_bind_mask+0x60/0x60
 ret_from_fork+0x22/0x30

To synchronize all dlm scand messages we stop it right before shutdown
hook.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
eec054b5a7 fs: dlm: flush swork on shutdown
This patch fixes the flushing of send work before shutdown. The function
cancel_work_sync() is not the right workqueue functionality to use here
as it would cancel the work if the work queues itself. In cases of
EAGAIN in send() for dlm message we need to be sure that everything is
send out before. The function flush_work() will ensure that every send
work is be done inclusive in EAGAIN cases.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
df9e06b800 fs: dlm: remove unaligned memory access handling
This patch removes unaligned memory access handling for receiving
midcomms messages. This handling will not fix the unaligned memory
access in general. All messages should be length aligned to 8 bytes,
there exists cases where this isn't the case. It's part of the sending
handling to not send such messages. As the sending handling itself, with
the internal allocator of page buffers, can occur in unaligned memory
access of dlm message fields we just ignore that problem for now as it
seems this code is used by architecture which can handle it.

This patch adds a comment to take care about that problem in a major
bump of dlm protocol.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
710176e836 fs: dlm: check on minimum msglen size
This patch adds an additional check for minimum dlm header size which is
an invalid dlm message and signals a broken stream. A msglen field cannot
be less than the dlm header size because the field is inclusive header
lengths.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
f0747ebf48 fs: dlm: simplify writequeue handling
This patch cleans up the current dlm sending allocator handling by using
some named macros, list functionality and removes some goto statements.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
e1a7cbce53 fs: dlm: use GFP_ZERO for page buffer
This patch uses GFP_ZERO for allocate a page for the internal dlm
sending buffer allocator instead of calling memset zero after every
allocation. An already allocated space will never be reused again.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
c45674fbdd fs: dlm: change allocation limits
While running tcpkill I experienced invalid header length values while
receiving to check that a node doesn't try to send a invalid dlm message
we also check on applications minimum allocation limit. Also use
DEFAULT_BUFFER_SIZE as maximum allocation limit. The define
LOWCOMMS_MAX_TX_BUFFER_LEN is to calculate maximum buffer limits on
application layer, future midcomms layer will subtract their needs from
this define.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
517461630d fs: dlm: add check if dlm is currently running
This patch adds checks for dlm config attributes regarding to protocol
parameters as it makes only sense to change them when dlm is not running.
It also adds a check for valid protocol specifiers and return invalid
argument if they are not supported.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
8aa9540b49 fs: dlm: add errno handling to check callback
This allows to return individual errno values for the config attribute
check callback instead of returning invalid argument only.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
e9a470acd9 fs: dlm: set subclass for othercon sock_mutex
This patch sets the lockdep subclass for the othercon socket mutex. In
various places the connection socket mutex is held while locking the
othercon socket mutex. This patch will remove lockdep warnings when such
case occurs.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
b30a624f50 fs: dlm: set connected bit after accept
This patch sets the CF_CONNECTED bit when dlm accepts a connection from
another node. If we don't set this bit, next time if the connection
socket gets writable it will assume an event that the connection is
successfully connected. However that is only the case when the
connection did a connect.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
e125fbeb53 fs: dlm: fix mark setting deadlock
This patch fixes an deadlock issue when dlm_lowcomms_close() is called.
When dlm_lowcomms_close() is called the clusters_root.subsys.su_mutex is
held to remove configfs items. At this time we flushing (e.g.
cancel_work_sync()) the workers of send and recv workqueue. Due the fact
that we accessing configfs items (mark values), these workers will lock
clusters_root.subsys.su_mutex as well which are already hold by
dlm_lowcomms_close() and ends in a deadlock situation.

[67170.703046] ======================================================
[67170.703965] WARNING: possible circular locking dependency detected
[67170.704758] 5.11.0-rc4+ #22 Tainted: G        W
[67170.705433] ------------------------------------------------------
[67170.706228] dlm_controld/280 is trying to acquire lock:
[67170.706915] ffff9f2f475a6948 ((wq_completion)dlm_recv){+.+.}-{0:0}, at: __flush_work+0x203/0x4c0
[67170.708026]
               but task is already holding lock:
[67170.708758] ffffffffa132f878 (&clusters_root.subsys.su_mutex){+.+.}-{3:3}, at: configfs_rmdir+0x29b/0x310
[67170.710016]
               which lock already depends on the new lock.

The new behaviour adds the mark value to the node address configuration
which doesn't require to held the clusters_root.subsys.su_mutex by
accessing mark values in a separate datastructure. However the mark
values can be set now only after a node address was set which is the
case when the user is using dlm_controld.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
92c48950b4 fs: dlm: fix debugfs dump
This patch fixes the following message which randomly pops up during
glocktop call:

seq_file: buggy .next function table_seq_next did not update position index

The issue is that seq_read_iter() in fs/seq_file.c also needs an
increment of the index in an non next record case as well which this
patch fixes otherwise seq_read_iter() will print out the above message.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring
4f19d071f9 fs: dlm: check on existing node address
This patch checks if we add twice the same address to a per node address
array. This should never be the case and we report -EEXIST to the user
space.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring
40c6b83e5a fs: dlm: constify addr_compare
This patch just constify some function parameter which should be have a
read access only.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring
1a26bfafbc fs: dlm: fix check for multi-homed hosts
This patch will use the runtime array size dlm_local_count variable
to check the actual size of the dlm_local_addr array. There exists
currently a cleanup bug, because the tcp_listen_for_all() functionality
might check on a dangled pointer.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring
d11ccd451b fs: dlm: listen socket out of connection hash
This patch introduces a own connection structure for the listen socket
handling instead of handling the listen socket as normal connection
structure in the connection hash. We can remove some nodeid equals zero
validation checks, because this nodeid should not exists anymore inside
the node hash. This patch also removes the sock mutex in
accept_from_sock() function because this function can't occur in another
parallel context if it's scheduled on only one workqueue.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring
13004e8afe fs: dlm: refactor sctp sock parameter
This patch refactors sctp_bind_addrs() to work with a socket parameter
instead of a connection parameter.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring
42873c903b fs: dlm: move shutdown action to node creation
This patch move the assignment for the shutdown action callback to the
node creation functionality.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring
0672c3c280 fs: dlm: move connect callback in node creation
This patch moves the assignment for the connect callback to the node
creation instead of assign some dummy functionality. The assignment
which connect functionality will be used will be detected according to
the configfs setting.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring
6cde210a97 fs: dlm: add helper for init connection
This patch will move the connection structure initialization into an
own function. This avoids cases to update the othercon initialization.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring
19633c7e20 fs: dlm: handle non blocked connect event
The manpage of connect shows that in non blocked mode a writeability
indicates successful connection event. This patch is handling this event
inside the writeability callback. In case of SCTP we use blocking
connect functionality which indicates a successful connect when the
function returns with a successful return value.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring
53a5edaa05 fs: dlm: flush othercon at close
This patch ensures we also flush the othercon writequeue when a lowcomms
close occurs.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00