Commit Graph

254 Commits

Author SHA1 Message Date
Alexander Aring
feae43f8aa fs: dlm: print cluster addr if non-cluster node connects
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>
2022-01-04 09:40:24 -06:00
Alexander Aring
e4dc81ed5a fs: dlm: memory cache for lowcomms hotpath
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>
2021-12-07 12:42:26 -06:00
Alexander Aring
3af2326ca0 fs: dlm: memory cache for writequeue_entry
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>
2021-12-07 12:42:26 -06:00
Alexander Aring
be3b0400ed fs: dlm: remove wq_alloc mutex
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>
2021-12-07 12:42:26 -06:00
Alexander Aring
bcbfea41e1 fs: dlm: check for pending users filling buffers
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>
2021-12-07 12:42:26 -06:00
Alexander Aring
1b9beda83e fs: dlm: fix build with CONFIG_IPV6 disabled
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>
2021-11-17 08:46:23 -06:00
Alexander Aring
92c4460538 fs: dlm: replace use of socket sk_callback_lock with sock_lock
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>
2021-11-15 11:49:18 -06:00
Alexander Aring
4c3d90570b fs: dlm: don't call kernel_getpeername() in error_report()
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>
2021-11-15 11:49:18 -06:00
Alexander Aring
b87b1883ef fs: dlm: remove double list_first_entry call
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>
2021-11-03 16:07:20 -05:00
Alexander Aring
5c16febbc1 fs: dlm: let handle callback data as void
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>
2021-11-02 14:39:20 -05:00
Alexander Aring
92732376fd fs: dlm: trace socket handling
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>
2021-11-02 14:39:20 -05:00
Alexander Aring
fe93367541 fs: dlm: remove check SCTP is loaded message
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>
2021-11-02 14:39:20 -05:00
Alexander Aring
b97f85259f fs: dlm: implement delayed ack handling
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>
2021-08-19 11:33:03 -05:00
Alexander Aring
62699b3f0a fs: dlm: move receive loop into receive handler
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>
2021-07-19 11:56:36 -05:00
Alexander Aring
c51b022179 fs: dlm: fix multiple empty writequeue alloc
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>
2021-07-19 11:56:35 -05:00
Alexander Aring
8728a455d2 fs: dlm: generic connect func
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>
2021-07-19 11:56:34 -05:00
Alexander Aring
90d21fc047 fs: dlm: auto load sctp module
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>
2021-07-19 11:56:26 -05:00
Alexander Aring
2dc6b1158c fs: dlm: introduce generic listen
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>
2021-07-19 11:53:43 -05:00
Alexander Aring
a66c008cd1 fs: dlm: move to static proto ops
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>
2021-07-19 11:53:43 -05:00
Alexander Aring
66d5955a09 fs: dlm: introduce con_next_wq helper
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>
2021-07-19 11:53:43 -05:00
Alexander Aring
052849beea fs: dlm: clear CF_APP_LIMITED on close
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>
2021-07-19 11:53:43 -05:00
Alexander Aring
feb704bd17 fs: dlm: use sk->sk_socket instead of con->sock
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>
2021-07-19 11:53:43 -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
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
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
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
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
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
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
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
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
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
Alexander Aring
692f51c8cb fs: dlm: add get buffer error handling
This patch adds an error handling to the get buffer functionality if the
user is requesting a buffer length which is more than possible of
the internal buffer allocator. This should never happen because specific
handling decided by compile time, but will warn if somebody forget about
to handle this limitation right.

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
5cbec208dc fs: dlm: fix proper srcu api call
This patch will use call_srcu() instead of call_rcu() because the
related datastructure resource are handled under srcu context. I assume
the current code is fine anyway since free_conn() must be called when
the related resource are not in use otherwise. However it will correct
the overall handling in a srcu context.

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
4f2b30fd9b fs: dlm: fix race in nodeid2con
This patch fixes a race in nodeid2con in cases that we parallel running
a lookup and both will create a connection structure for the same nodeid.
It's a rare case to create a new connection structure to keep reader
lockless we just do a lookup inside the protection area again and drop
previous work if this race happens.

Fixes: a47666eb76 ("fs: dlm: make connection hash lockless")
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-10-01 09:25:07 -05:00
Alexander Aring
4798cbbfbd fs: dlm: rework receive handling
This patch reworks the current receive handling of dlm. As I tried to
change the send handling to fix reorder issues I took a look into the
receive handling and simplified it, it works as the following:

Each connection has a preallocated receive buffer with a minimum length of
4096. On receive, the upper layer protocol will process all dlm message
until there is not enough data anymore. If there exists "leftover" data at
the end of the receive buffer because the dlm message wasn't fully received
it will be copied to the begin of the preallocated receive buffer. Next
receive more data will be appended to the previous "leftover" data and
processing will begin again.

This will remove a lot of code of the current mechanism. Inside the
processing functionality we will ensure with a memmove() that the dlm
message should be memory aligned. To have a dlm message always started
at the beginning of the buffer will reduce some amount of memmove()
calls because src and dest pointers are the same.

The cluster attribute "buffer_size" becomes a new meaning, it's now the
size of application layer receive buffer size. If this is changed during
runtime the receive buffer will be reallocated. It's important that the
receive buffer size has at minimum the size of the maximum possible dlm
message size otherwise the received message cannot be placed inside
the receive buffer size.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-09-29 14:00:32 -05:00
Alexander Aring
3f78cd7d24 fs: dlm: fix mark per nodeid setting
This patch fixes to set per nodeid mark configuration for accepted
sockets as well. Before this patch only the listen socket mark value was
used for all accepted connections. This patch will ensure that the
cluster mark attribute value will be always used for all sockets, if a
per nodeid mark value is specified dlm will use this value for the
specific node.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-09-29 14:00:32 -05:00
Alexander Aring
0461e0db94 fs: dlm: remove lock dependency warning
During my experiments to make dlm robust against tcpkill application I
was able to run sometimes in a circular lock dependency warning between
clusters_root.subsys.su_mutex and con->sock_mutex. We don't need to
held the sock_mutex when getting the mark value which held the
clusters_root.subsys.su_mutex. This patch moves the specific handling
just before the sock_mutex will be held.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-09-29 14:00:32 -05:00
Alexander Aring
7ae0451e2e fs: dlm: use free_con to free connection
This patch use free_con() functionality to free the listen connection if
listen fails. It also fixes an issue that a freed resource is still part
of the connection_hash as hlist_del() is not called in this case. The
only difference is that free_con() handles othercon as well, but this is
never been set for the listen connection.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring
948c47e9bc fs: dlm: handle possible othercon writequeues
This patch adds free of possible other writequeue entries in othercon
member of struct connection.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring
0de984323a fs: dlm: move free writequeue into con free
This patch just move the free of struct connection member writequeue
into the functionality when struct connection will be freed instead of
doing two iterations.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring
043697f030 fs: dlm: fix dlm_local_addr memory leak
This patch fixes the following memory detected by kmemleak and umount
gfs2 filesystem which removed the last lockspace:

unreferenced object 0xffff9264f4f48f00 (size 128):
  comm "mount", pid 425, jiffies 4294690253 (age 48.159s)
  hex dump (first 32 bytes):
    02 00 52 48 c0 a8 7a fb 00 00 00 00 00 00 00 00  ..RH..z.........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<0000000067a34940>] kmemdup+0x18/0x40
    [<00000000c935f9ab>] init_local+0x4c/0xa0
    [<00000000bbd286ef>] dlm_lowcomms_start+0x28/0x160
    [<00000000a86625cb>] dlm_new_lockspace+0x7e/0xb80
    [<000000008df6cd63>] gdlm_mount+0x1cc/0x5de
    [<00000000b67df8c7>] gfs2_lm_mount.constprop.0+0x1a3/0x1d3
    [<000000006642ac5e>] gfs2_fill_super+0x717/0xba9
    [<00000000d3ab7118>] get_tree_bdev+0x17f/0x280
    [<000000001975926e>] gfs2_get_tree+0x21/0x90
    [<00000000561ce1c4>] vfs_get_tree+0x28/0xc0
    [<000000007fecaf63>] path_mount+0x434/0xc00
    [<00000000636b9594>] __x64_sys_mount+0xe3/0x120
    [<00000000cc478a33>] do_syscall_64+0x33/0x40
    [<00000000ce9ccf01>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring
a47666eb76 fs: dlm: make connection hash lockless
There are some problems with the connections_lock. During my
experiements I saw sometimes circular dependencies with sock_lock.
The reason here might be code parts which runs nodeid2con() before
or after sock_lock is acquired.

Another issue are missing locks in for_conn() iteration. Maybe this
works fine because for_conn() is running in a context where
connection_hash cannot be manipulated by others anymore.

However this patch changes the connection_hash to be protected by
sleepable rcu. The hotpath function __find_con() is implemented
lockless as it is only a reader of connection_hash and this hopefully
fixes the circular locking dependencies. The iteration for_conn() will
still call some sleepable functionality, that's why we use sleepable rcu
in this case.

This patch removes the kmemcache functionality as I think I need to
make some free() functionality via call_rcu(). However allocation time
isn't here an issue. The dlm_allow_con will not be protected by a lock
anymore as I think it's enough to just set and flush workqueues
afterwards.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring
aa7ab1e208 fs: dlm: synchronize dlm before shutdown
This patch moves the dlm workqueue dlm synchronization before shutdown
handling. The patch just flushes all pending work before starting to
shutdown the connection. At least for the send_workqeue we should flush
the workqueue to make sure there is no new connection handling going on
as dlm_allow_conn switch is turned to false before.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring
055923bf6b fs: dlm: implement tcp graceful shutdown
During my code inspection I saw there is no implementation of a graceful
shutdown for tcp. This patch will introduce a graceful shutdown for tcp
connections. The shutdown is implemented synchronized as
dlm_lowcomms_stop() is called to end all dlm communication. After shutdown
is done, a lot of flush and closing functionality will be called. However
I don't see a problem with that.

The waitqueue for synchronize the shutdown has a timeout of 10 seconds, if
timeout a force close will be exectued.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:54 -05:00
Alexander Aring
ba3ab3ca68 fs: dlm: change handling of reconnects
This patch changes the handling of reconnects. At first we only close
the connection related to the communication failure. If we get a new
connection for an already existing connection we close the existing
connection and take the new one.

This patch improves significantly the stability of tcp connections while
running "tcpkill -9 -i $IFACE port 21064" while generating a lot of dlm
messages e.g. on a gfs2 mount with many files. My test setup shows that a
deadlock is "more" unlikely. Before this patch I wasn't able to get
not a deadlock after 5 seconds. After this patch my observation is
that it's more likely to survive after 5 seconds and more, but still a
deadlock occurs after certain time. My guess is that there are still
"segments" inside the tcp writequeue or retransmit queue which get dropped
when receiving a tcp reset [1]. Hard to reproduce because the right message
need to be inside these queues, which might even be in the 5 first seconds
with this patch.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/net/ipv4/tcp_input.c?h=v5.8-rc6#n4122

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:54 -05:00
Alexander Aring
0ea47e4d21 fs: dlm: don't close socket on invalid message
This patch doesn't close sockets when there is an invalid dlm message
received. The connection will probably reconnect anyway so. To not
close the connection will reduce the number of possible failtures.
As we don't have a different strategy to react on such scenario
just keep going the connection and ignore the message.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:53 -05:00
Alexander Aring
9c9f168f5b fs: dlm: set skb mark per peer socket
This patch adds support to set the skb mark value for the DLM tcp and
sctp socket per peer. The mark value will be offered as per comm value
of configfs. At creation time of the peer socket it will be set as
socket option.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:52 -05:00
Alexander Aring
a5b7ab6352 fs: dlm: set skb mark for listen socket
This patch adds support to set the skb mark value for the DLM listen
tcp and sctp sockets. The mark value will be offered as cluster
configuration. At creation time of the listen socket it will be set as
socket option.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:51 -05:00
Christoph Hellwig
c0425a4249 net: add a new bind_add method
The SCTP protocol allows to bind multiple address to a socket.  That
feature is currently only exposed as a socket option.  Add a bind_add
method struct proto that allows to bind additional addresses, and
switch the dlm code to use the method instead of going through the
socket option from kernel space.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-29 13:10:39 -07:00
Christoph Hellwig
40ef92c6ec sctp: add sctp_sock_set_nodelay
Add a helper to directly set the SCTP_NODELAY sockopt from kernel space
without going through a fake uaccess.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-29 13:10:39 -07:00
Christoph Hellwig
12abc5ee78 tcp: add tcp_sock_set_nodelay
Add a helper to directly set the TCP_NODELAY sockopt from kernel space
without going through a fake uaccess.  Cleanup the callers to avoid
pointless wrappers now that this is a simple function call.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28 11:11:45 -07:00
Christoph Hellwig
26cfabf9cd net: add sock_set_rcvbuf
Add a helper to directly set the SO_RCVBUFFORCE sockopt from kernel space
without going through a fake uaccess.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28 11:11:44 -07:00
Christoph Hellwig
ce3d9544ce net: add sock_set_keepalive
Add a helper to directly set the SO_KEEPALIVE sockopt from kernel space
without going through a fake uaccess.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28 11:11:44 -07:00
Christoph Hellwig
76ee0785f4 net: add sock_set_sndtimeo
Add a helper to directly set the SO_SNDTIMEO_NEW sockopt from kernel
space without going through a fake uaccess.  The interface is
simplified to only pass the seconds value, as that is the only
thing needed at the moment.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28 11:11:44 -07:00
Christoph Hellwig
b58f0e8f38 net: add sock_set_reuseaddr
Add a helper to directly set the SO_REUSEADDR sockopt from kernel space
without going through a fake uaccess.

For this the iscsi target now has to formally depend on inet to avoid
a mostly theoretical compile failure.  For actual operation it already
did depend on having ipv4 or ipv6 support.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28 11:11:44 -07:00
Christoph Hellwig
0774dc7643 dlm: use the tcp version of accept_from_sock for sctp as well
The only difference between a few missing fixes applied to the SCTP
one is that TCP uses ->getpeername to get the remote address, while
SCTP uses kernel_getsockopt(.. SCTP_PRIMARY_ADDR).  But given that
getpeername is defined to return the primary address for sctp, there
doesn't seem to be any reason for the different way of quering the
peername, or all the code duplication.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-27 15:11:33 -07:00
Arnd Bergmann
5311f707b4 dlm: use SO_SNDTIMEO_NEW instead of SO_SNDTIMEO_OLD
Eliminate one more use of 'struct timeval' from the kernel so
we can eventually remove the definition as well.

The kernel supports the new format with a 64-bit time_t version
of timeval here, so use that instead of the old timeval.

Acked-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-12-18 18:07:31 +01:00
David Windsor
b355516f45 dlm: check if workqueues are NULL before flushing/destroying
If the DLM lowcomms stack is shut down before any DLM
traffic can be generated, flush_workqueue() and
destroy_workqueue() can be called on empty send and/or recv
workqueues.

Insert guard conditionals to only call flush_workqueue()
and destroy_workqueue() on workqueues that are not NULL.

Signed-off-by: David Windsor <dwindsor@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2019-07-11 11:01:58 -05:00
Thomas Gleixner
2522fe45a1 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 193
Based on 1 normalized pattern(s):

  this copyrighted material is made available to anyone wishing to use
  modify copy or redistribute it subject to the terms and conditions
  of the gnu general public license v 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 45 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170027.342746075@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:21 -07:00
Deepa Dinamani
45bdc66159 socket: Rename SO_RCVTIMEO/ SO_SNDTIMEO with _OLD suffixes
SO_RCVTIMEO and SO_SNDTIMEO socket options use struct timeval
as the time format. struct timeval is not y2038 safe.
The subsequent patches in the series add support for new socket
timeout options with _NEW suffix that will use y2038 safe
data structures. Although the existing struct timeval layout
is sufficiently wide to represent timeouts, because of the way
libc will interpret time_t based on user defined flag, these
new flags provide a way of having a structure that is the same
for all architectures consistently.
Rename the existing options with _OLD suffix forms so that the
right option is enabled for userspace applications according
to the architecture and time_t definition of libc.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Cc: ccaulfie@redhat.com
Cc: deller@gmx.de
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: rth@twiddle.net
Cc: cluster-devel@redhat.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-03 11:17:31 -08:00
David Howells
aa563d7bca iov_iter: Separate type from direction and use accessor functions
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:07 +01:00
Gang He
da3627c30d dlm: remove O_NONBLOCK flag in sctp_connect_to_sock
We should remove O_NONBLOCK flag when calling sock->ops->connect()
in sctp_connect_to_sock() function.
Why?
1. up to now, sctp socket connect() function ignores the flag argument,
that means O_NONBLOCK flag does not take effect, then we should remove
it to avoid the confusion (but is not urgent).
2. for the future, there will be a patch to fix this problem, then the flag
argument will take effect, the patch has been queued at https://git.kernel.o
rg/pub/scm/linux/kernel/git/davem/net.git/commit/net/sctp?id=644fbdeacf1d3ed
d366e44b8ba214de9d1dd66a9.
But, the O_NONBLOCK flag will make sock->ops->connect() directly return
without any wait time, then the connection will not be established, DLM kernel
module will call sock->ops->connect() again and again, the bad results are,
CPU usage is almost 100%, even trigger soft_lockup problem if the related
configurations are enabled,
DLM kernel module also prints lots of messages like,
[Fri Apr 27 11:23:43 2018] dlm: connecting to 172167592
[Fri Apr 27 11:23:43 2018] dlm: connecting to 172167592
[Fri Apr 27 11:23:43 2018] dlm: connecting to 172167592
[Fri Apr 27 11:23:43 2018] dlm: connecting to 172167592
The upper application (e.g. ocfs2 mount command) is hanged at new_lockspace(),
the whole backtrace is as below,
tb0307-nd2:~ # cat /proc/2935/stack
[<0>] new_lockspace+0x957/0xac0 [dlm]
[<0>] dlm_new_lockspace+0xae/0x140 [dlm]
[<0>] user_cluster_connect+0xc3/0x3a0 [ocfs2_stack_user]
[<0>] ocfs2_cluster_connect+0x144/0x220 [ocfs2_stackglue]
[<0>] ocfs2_dlm_init+0x215/0x440 [ocfs2]
[<0>] ocfs2_fill_super+0xcb0/0x1290 [ocfs2]
[<0>] mount_bdev+0x173/0x1b0
[<0>] mount_fs+0x35/0x150
[<0>] vfs_kern_mount.part.23+0x54/0x100
[<0>] do_mount+0x59a/0xc40
[<0>] SyS_mount+0x80/0xd0
[<0>] do_syscall_64+0x76/0x140
[<0>] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[<0>] 0xffffffffffffffff

So, I think we should remove O_NONBLOCK flag here, since DLM kernel module can
not handle non-block sockect in connect() properly.

Signed-off-by: Gang He <ghe@suse.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2018-05-29 10:48:35 -05:00
Gang He
f706d83015 dlm: make sctp_connect_to_sock() return in specified time
When the user setup a two-ring cluster, DLM kernel module
will automatically selects to use SCTP protocol to communicate
between each node. There will be about 5 minute hang in DLM
kernel module, in case one ring is broken before switching to
another ring, this will potentially affect the dependent upper
applications, e.g. ocfs2, gfs2, clvm and clustered-MD, etc.
Unfortunately, if the user setup a two-ring cluster, we can not
specify DLM communication protocol with TCP explicitly, since
DLM kernel module only supports SCTP protocol for multiple
ring cluster.
Base on my investigation, the time is spent in sock->ops->connect()
function before returns ETIMEDOUT(-110) error, since O_NONBLOCK
argument in connect() function does not work here, then we should
make sock->ops->connect() function return in specified time via
setting socket SO_SNDTIMEO atrribute.

Signed-off-by: Gang He <ghe@suse.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2018-05-02 10:28:35 -05:00
Gang He
b09c603ca4 dlm: fix a clerical error when set SCTP_NODELAY
There is a clerical error when turn off Nagle's algorithm in
sctp_connect_to_sock() function, this results in turn off
Nagle's algorithm failure.
After this correction, DLM performance will be improved obviously
when using SCTP procotol.

Signed-off-by: Gang He <ghe@suse.com>
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David Teigland <teigland@redhat.com>
2018-05-02 10:22:25 -05:00
Denys Vlasenko
9b2c45d479 net: make getname() functions return length rather than use int* parameter
Changes since v1:
Added changes in these files:
    drivers/infiniband/hw/usnic/usnic_transport.c
    drivers/staging/lustre/lnet/lnet/lib-socket.c
    drivers/target/iscsi/iscsi_target_login.c
    drivers/vhost/net.c
    fs/dlm/lowcomms.c
    fs/ocfs2/cluster/tcp.c
    security/tomoyo/network.c

Before:
All these functions either return a negative error indicator,
or store length of sockaddr into "int *socklen" parameter
and return zero on success.

"int *socklen" parameter is awkward. For example, if caller does not
care, it still needs to provide on-stack storage for the value
it does not need.

None of the many FOO_getname() functions of various protocols
ever used old value of *socklen. They always just overwrite it.

This change drops this parameter, and makes all these functions, on success,
return length of sockaddr. It's always >= 0 and can be differentiated
from an error.

Tests in callers are changed from "if (err)" to "if (err < 0)", where needed.

rpc_sockname() lost "int buflen" parameter, since its only use was
to be passed to kernel_getsockname() as &buflen and subsequently
not used in any way.

Userspace API is not changed.

    text    data     bss      dec     hex filename
30108430 2633624  873672 33615726 200ef6e vmlinux.before.o
30108109 2633612  873672 33615393 200ee21 vmlinux.o

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
CC: linux-bluetooth@vger.kernel.org
CC: linux-decnet-user@lists.sourceforge.net
CC: linux-wireless@vger.kernel.org
CC: linux-rdma@vger.kernel.org
CC: linux-sctp@vger.kernel.org
CC: linux-nfs@vger.kernel.org
CC: linux-x25@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-12 14:15:04 -05:00
Al Viro
c8c7840ea9 dlm: switch to sock_recvmsg()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-12-02 20:37:47 -05:00
tsutomu.owa@toshiba.co.jp
26b41099e7 DLM: fix NULL pointer dereference in send_to_sock()
The writequeue and writequeue_lock member of othercon was not initialized.
If lowcomms_state_change() is called from network layer, othercon->swork
may be scheduled. In this case, send_to_sock() will generate a NULL pointer
reference. We avoid this problem by correctly initializing writequeue and
writequeue_lock member of othercon.

Signed-off-by: Tadashi Miyauchi <miyauchi@toshiba-tops.co.jp>
Signed-off-by: Tsutomu Owa <tsutomu.owa@toshiba.co.jp>
Signed-off-by: David Teigland <teigland@redhat.com>
2017-09-25 12:45:21 -05:00
tsutomu.owa@toshiba.co.jp
0aa18464c8 DLM: fix to reschedule rwork
When an error occurs in kernel_recvmsg or kernel_sendpage and
close_connection is called and receive work is already scheduled,
receive work is canceled. In that case, the receive work will not
be scheduled forever after reconnection, because CF_READ_PENDING
flag is established.

Signed-off-by: Tadashi Miyauchi <miyauchi@toshiba-tops.co.jp>
Signed-off-by: Tsutomu Owa <tsutomu.owa@toshiba.co.jp>
Signed-off-by: David Teigland <teigland@redhat.com>
2017-09-25 12:45:21 -05:00
tsutomu.owa@toshiba.co.jp
93eaadebe9 DLM: fix to use sk_callback_lock correctly
In the current implementation, we think that exclusion control between
processing to set the callback function to the connection structure and
processing to refer to the connection structure from the callback function
was not enough. We fix them.

Signed-off-by: Tadashi Miyauchi <miyauchi@toshiba-tops.co.jp>
Signed-off-by: Tsutomu Owa <tsutomu.owa@toshiba.co.jp>
Signed-off-by: David Teigland <teigland@redhat.com>
2017-09-25 12:45:21 -05:00
tsutomu.owa@toshiba.co.jp
3421fb15be DLM: fix memory leak in tcp_accept_from_sock()
The sk member of the socket generated by sock_create_kern() is overwritten
by ops->accept(). So the previous sk will not be released.
We use kernel_accept() instead of sock_create_kern() and ops->accept().

Signed-off-by: Tadashi Miyauchi <miyauchi@toshiba-tops.co.jp>
Signed-off-by: Tsutomu Owa <tsutomu.owa@toshiba.co.jp>
Signed-off-by: David Teigland <teigland@redhat.com>
2017-09-25 12:45:21 -05:00
tsutomu.owa@toshiba.co.jp
173a31fe2b DLM: use CF_CLOSE flag to stop dlm_send correctly
If reconnection fails while executing dlm_lowcomms_stop,
dlm_send will not stop.

Signed-off-by: Tadashi Miyauchi <miyauchi@toshiba-tops.co.jp>
Signed-off-by: Tsutomu Owa <tsutomu.owa@toshiba.co.jp>
Signed-off-by: David Teigland <teigland@redhat.com>
2017-09-25 12:45:21 -05:00
tsutomu.owa@toshiba.co.jp
8a4abb0819 DLM: Reanimate CF_WRITE_PENDING flag
CF_WRITE_PENDING flag has been reanimated to make dlm_send stop properly
when running dlm_lowcomms_stop.

Signed-off-by: Tadashi Miyauchi <miyauchi@toshiba-tops.co.jp>
Signed-off-by: Tsutomu Owa <tsutomu.owa@toshiba.co.jp>
Signed-off-by: David Teigland <teigland@redhat.com>
2017-09-25 12:45:21 -05:00
tsutomu.owa@toshiba.co.jp
c553e173b0 DLM: close othercon at send/receive error
If an error occurs in the sending / receiving process, if othercon
exists, sending / receiving processing using othercon may also result
in an error. We fix to pre-close othercon as well.

Signed-off-by: Tadashi Miyauchi <miyauchi@toshiba-tops.co.jp>
Signed-off-by: Tsutomu Owa <tsutomu.owa@toshiba.co.jp>
Signed-off-by: David Teigland <teigland@redhat.com>
2017-09-25 12:45:21 -05:00