This patch prints the cluster node address if a non-cluster node
(according to the dlm config setting) tries to connect. The current
hexdump call will print in a different loglevel and only available if
dynamic debug is enabled. Additional we using the ip address format
strings to print an IETF ip4/6 string represenation.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch introduces a kmem cache for dlm_msg handles which are used
always if dlm sends a message out. Even if their are covered by midcomms
layer or not.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch introduces a kmem cache for writequeue entry. A writequeue
entry get quite a lot allocated if dlm transmit messages.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch cleanups the code for allocating a new buffer in the dlm
writequeue mechanism. There was a possible tuneup to allow scheduling
while a new writequeue entry needs to be allocated because either no
sending page is available or are full. To avoid multiple concurrent
users checking at the same time if an entry is available or full
alloc_wq was introduce that those are waiting if there is currently a
new writequeue entry in process to be queued so possible further users
will check on the new allocated writequeue entry if it's full.
To simplify the code we just remove this mutex and switch that the
already introduced spin lock will be held during writequeue check,
allocation and queueing. So other users can never check on available
writequeues while there is a new one in process but not queued yet.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Currently we don't care if the DLM application stack is filling buffers
(not committed yet) while we transmit some already committed buffers.
By checking on active writequeue users before dequeue a writequeue entry
we know there is coming more data and do nothing. We wait until the send
worker will be triggered again if the writequeue entry users hit zero.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch will surround the AF_INET6 case in sk_error_report() of dlm
with a #if IS_ENABLED(CONFIG_IPV6). The field sk->sk_v6_daddr is not
defined when CONFIG_IPV6 is disabled. If CONFIG_IPV6 is disabled, the
socket creation with AF_INET6 should already fail because a runtime
check if AF_INET6 is registered. However if there is the possibility
that AF_INET6 is set as sk_family the sk_error_report() callback will
print then an invalid family type error.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 4c3d90570b ("fs: dlm: don't call kernel_getpeername() in error_report()")
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch will replace the use of socket sk_callback_lock lock and uses
socket lock instead. Some users like sunrpc, see commit ea9afca88b
("SUNRPC: Replace use of socket sk_callback_lock with sock_lock") moving
from sk_callback_lock to sock_lock which seems to be held when the socket
callbacks are called.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
In some cases kernel_getpeername() will held the socket lock which is
already held when the socket layer calls error_report() callback. Since
commit 9dfc685e02 ("inet: remove races in inet{6}_getname()") this
problem becomes more likely because the socket lock will be held always.
You will see something like:
bob9-u5 login: [ 562.316860] BUG: spinlock recursion on CPU#7, swapper/7/0
[ 562.318562] lock: 0xffff8f2284720088, .magic: dead4ead, .owner: swapper/7/0, .owner_cpu: 7
[ 562.319522] CPU: 7 PID: 0 Comm: swapper/7 Not tainted 5.15.0+ #135
[ 562.320346] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.13.0-2.module+el8.3.0+7353+9de0a3cc 04/01/2014
[ 562.321277] Call Trace:
[ 562.321529] <IRQ>
[ 562.321734] dump_stack_lvl+0x33/0x42
[ 562.322282] do_raw_spin_lock+0x8b/0xc0
[ 562.322674] lock_sock_nested+0x1e/0x50
[ 562.323057] inet_getname+0x39/0x110
[ 562.323425] ? sock_def_readable+0x80/0x80
[ 562.323838] lowcomms_error_report+0x63/0x260 [dlm]
[ 562.324338] ? wait_for_completion_interruptible_timeout+0xd2/0x120
[ 562.324949] ? lock_timer_base+0x67/0x80
[ 562.325330] ? do_raw_spin_unlock+0x49/0xc0
[ 562.325735] ? _raw_spin_unlock_irqrestore+0x1e/0x40
[ 562.326218] ? del_timer+0x54/0x80
[ 562.326549] sk_error_report+0x12/0x70
[ 562.326919] tcp_validate_incoming+0x3c8/0x530
[ 562.327347] ? kvm_clock_read+0x14/0x30
[ 562.327718] ? ktime_get+0x3b/0xa0
[ 562.328055] tcp_rcv_established+0x121/0x660
[ 562.328466] tcp_v4_do_rcv+0x132/0x260
[ 562.328835] tcp_v4_rcv+0xcea/0xe20
[ 562.329173] ip_protocol_deliver_rcu+0x35/0x1f0
[ 562.329615] ip_local_deliver_finish+0x54/0x60
[ 562.330050] ip_local_deliver+0xf7/0x110
[ 562.330431] ? inet_rtm_getroute+0x211/0x840
[ 562.330848] ? ip_protocol_deliver_rcu+0x1f0/0x1f0
[ 562.331310] ip_rcv+0xe1/0xf0
[ 562.331603] ? ip_local_deliver+0x110/0x110
[ 562.332011] __netif_receive_skb_core+0x46a/0x1040
[ 562.332476] ? inet_gro_receive+0x263/0x2e0
[ 562.332885] __netif_receive_skb_list_core+0x13b/0x2c0
[ 562.333383] netif_receive_skb_list_internal+0x1c8/0x2f0
[ 562.333896] ? update_load_avg+0x7e/0x5e0
[ 562.334285] gro_normal_list.part.149+0x19/0x40
[ 562.334722] napi_complete_done+0x67/0x160
[ 562.335134] virtnet_poll+0x2ad/0x408 [virtio_net]
[ 562.335644] __napi_poll+0x28/0x140
[ 562.336012] net_rx_action+0x23d/0x300
[ 562.336414] __do_softirq+0xf2/0x2ea
[ 562.336803] irq_exit_rcu+0xc1/0xf0
[ 562.337173] common_interrupt+0xb9/0xd0
It is and was always forbidden to call kernel_getpeername() in context
of error_report(). To get rid of the problem we access the destination
address for the peer over the socket structure. While on it we fix to
print out the destination port of the inet socket.
Fixes: 1a31833d08 ("DLM: Replace nodeid_to_addr with kernel_getpeername")
Reported-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch removes a list_first_entry() call which is already done by
the previous con_next_wq() call.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch changes the dlm_lowcomms_new_msg() function pointer private data
from "struct mhandle *" to "void *" to provide different structures than
just "struct mhandle".
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch adds tracepoints for dlm socket receive and send
functionality. We can use it to track how much data was send or received
to or from a specific nodeid.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Since commit 764ff4011424 ("fs: dlm: auto load sctp module") we try
load the sctp module before we try to create a sctp kernel socket. That
a socket creation fails now has more likely other reasons. This patch
removes the part of error to load the sctp module and instead printout
the error code.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch changes that we don't ack each message. Lowcomms will take
care about to send an ack back after a bulk of messages was processed.
Currently it's only when the whole receive buffer was processed, there
might better positions to send an ack back but only the lowcomms
implementation know when there are more data to receive. This patch has
also disadvantages that we might retransmit more on errors, however this
is a very rare case.
Tested with make_panic on gfs2 with three nodes by running:
trace-cmd record -p function -l 'dlm_send_ack' sleep 100
and
trace-cmd report | wc -l
Before patch:
- 20548
- 21376
- 21398
After patch:
- 18338
- 20679
- 19949
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch moves the kernel_recvmsg() loop call into the
receive_from_sock() function instead of doing the loop outside the
function and abort the loop over it's return value.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch will add a mutex that a connection can allocate a writequeue
entry buffer only at a sleepable context at one time. If multiple caller
waits at the writequeue spinlock and the spinlock gets release it could
be that multiple new writequeue page buffers were allocated instead of
allocate one writequeue page buffer and other waiters will use remaining
buffer of it. It will only be the case for sleepable context which is
the common case. In non-sleepable contexts like retransmission we just
don't care about such behaviour.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch adds a generic connect function for TCP and SCTP. If the
connect functionality differs from each other additional callbacks in
dlm_proto_ops were added. The sockopts callback handling will guarantee
that sockets created by connect() will use the same options as sockets
created by accept().
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch adds a "for now" better handling of missing SCTP support in
the kernel and try to load the sctp module if SCTP is set.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch combines each transport layer listen functionality into one
listen function. Per transport layer differences are provided by
additional callbacks in dlm_proto_ops.
This patch drops silently sock_set_keepalive() for listen tcp sockets
only. This socket option is not set at connecting sockets, I also don't
see the sense of set keepalive for sockets which are created by accept()
only.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch moves the per transport socket callbacks to a static const
array. We can support only one transport socket for the init namespace
which will be determinted by reading the dlm config at lowcomms_start().
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch introduce a function to determine if something is ready to
being send in the writequeue. It's not just that the writequeue is not
empty additional the first entry need to have a valid length field.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
If send_to_sock() sets CF_APP_LIMITED limited bit and it has not been
cleared by a waiting lowcomms_write_space() yet and a close_connection()
apprears we should clear the CF_APP_LIMITED bit again because the
connection starts from a new state again at reconnect.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Instead of dereference "con->sock" we can get the socket structure over
"sk->sk_socket" as well. This patch will switch to this behaviour.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
