The dma related ...sync_sg... functions check the link state before the
dma function is actually called. But the check in smc_link_usable()
allows links in ACTIVATING state which are not yet mapped to dma memory.
Under high load it may happen that the sync_sg functions are called for
such a link which results in an debug output like
DMA-API: mlx5_core 0002:00:00.0: device driver tries to sync
DMA memory it has not allocated [device address=0x0000000103370000]
[size=65536 bytes]
To fix that introduce a helper to check for the link state ACTIVE and
use it where appropriate. And move the link state update to ACTIVATING
to the end of smcr_link_init() when most initial setup is done.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: d854fcbfae ("net/smc: add new link state and related helpers")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As smc client the delete link requests are assigned to the flow when
_any_ flow is active. This may break other flows that do not expect
delete link requests during their handling. Fix that by assigning the
request only when an add link flow is active. With that fix the code
for smc client and smc server is the same, so remove the separate
handling.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: 9ec6bf19ec ("net/smc: llc_del_link_work and use the LLC flow for delete link")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a new ib device is up smc will send an add link invitation to the
peer if needed. This is currently done with rudimentary flow control.
Under high workload these add link invitations can disturb other llc
flows because they arrive unexpected. Fix this by integrating the
invitations into the normal llc event flow and handle them as a flow.
While at it, check for already assigned requests in the flow before
the new add link request is assigned.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: 1f90a05d9f ("net/smc: add smcr_port_add() and smcr_link_up() processing")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To be save from unexpected or late llc response messages check if the
arrived message fits to the current flow type and drop out-of-flow
messages. And drop it when there is already a response assigned to
the flow.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: ef79d439cd ("net/smc: process llc responses in tasklet context")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A delete link could arrive during confirm link processing. Handle this
situation directly in smc_llc_srv_conf_link() rather than using the
logic in smc_llc_wait() to avoid the unexpected message handling there.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: 1551c95b61 ("net/smc: final part of add link processing as SMC server")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Wait for pending sends only when smc_switch_conns() found a link to move
the connections to. Do not wait during link freeing, this can lead to
permanent hang situations. And refuse to provide a new tx slot on an
unusable link.
Fixes: c6f02ebeea ("net/smc: switch connections to alternate link")
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There might be races in scenarios where both SMC link groups are on the
same system. Prevent that by creating separate wait queues for LLC flows
and messages. Switch to non-interruptable versions of wait_event() and
wake_up() for the llc flow waiter to make sure the waiters get control
sequentially. Fine tune the llc_flow_lock to include the assignment of
the message. Write to system log when an unexpected message was
dropped. And remove an extra indirection and use the existing local
variable lgr in smc_llc_enqueue().
Fixes: 555da9af82 ("net/smc: add event-based llc_flow framework")
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes gcc '-Wunused-but-set-variable' warning:
net/smc/smc_llc.c: In function 'smc_llc_cli_conf_link':
net/smc/smc_llc.c:753:31: warning:
variable 'del_llc' set but not used [-Wunused-but-set-variable]
struct smc_llc_msg_del_link *del_llc;
^
net/smc/smc_llc.c: In function 'smc_llc_process_srv_delete_link':
net/smc/smc_llc.c:1311:33: warning:
variable 'del_llc_resp' set but not used [-Wunused-but-set-variable]
struct smc_llc_msg_del_link *del_llc_resp;
^
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Print to system log when SMC links are available or go down, link group
state changes or pnetids are applied to and removed from devices.
The log entries are triggered by either user configuration actions or
adapter activation/deactivation events and are not expected to happen
often. The entries help SMC users to keep track of the SMC link group
status and to detect when actions are needed (like to add replacements
for failed adapters).
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
During SMC-R link establishment the peers exchange the link_uid that
is used for debugging purposes. Save the peer link_uid in smc_link so it
can be retrieved by the smc_diag netlink interface.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The link_uid of an SMC-R link is exchanged between SMC peers and its
value can be used for debugging purposes. Create a unique link_uid
during link initialization and use it in communication with SMC-R peers.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow to set the reason code for the link group termination, and set
meaningful values before termination processing is triggered. This
reason code is sent to the peer in the final delete link message.
When the LLC request or response layer receives a message type that was
not handled, drop a warning and terminate the link group.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
New connections must not be assigned to asymmetric links. Add asymmetric
link tagging using new link variable link_is_asym. The new helpers
smcr_lgr_set_type() and smcr_lgr_set_type_asym() are called to set the
state of the link group, and tag all links accordingly.
smcr_lgr_conn_assign_link() respects the link tagging and will not
assign new connections to links tagged as asymmetric link.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add smc_llc_send_message_wait() which uses smc_wr_tx_send_wait() to send
an LLC message and waits for the message send to complete.
smc_llc_send_link_delete_all() calls the new function to send an
DELETE_LINK,ALL LLC message. The RFC states that the sender of this type
of message needs to wait for the completion event of the message
transmission and can terminate the link afterwards.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add smc_switch_conns() to switch all connections from a link that is
going down. Find an other link to switch the connections to, and
switch each connection to the new link. smc_switch_cursor() updates the
cursors of a connection to the state of the last successfully sent CDC
message. When there is no link to switch to, terminate the link group.
Call smc_switch_conns() when a link is going down.
And with the possibility that links of connections can switch adapt CDC
and TX functions to detect and handle link switches.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As SMC server, when a second link was deleted, trigger the setup of an
asymmetric link. Do this by enqueueing a local ADD_LINK message which
is processed by the LLC layer as if it were received from peer. Do the
same when a new IB port became active and a new link could be created.
smc_llc_srv_add_link_local() enqueues a local ADD_LINK message.
And smc_llc_srv_delete_link_local() is used the same way to enqueue a
local DELETE_LINK message. This is used when an IB port is no longer
active.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add smc_llc_process_srv_delete_link() to process a DELETE_LINK request
as SMC server. When the request is to delete ALL links then terminate
the whole link group. If not, find the link to delete by its link_id,
send the DELETE_LINK request LLC message and wait for the response.
No matter if a response was received, clear the deleted link and update
the link group state.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add smc_llc_process_cli_delete_link() to process a DELETE_LINK request
as SMC client. When the request is to delete ALL links then terminate
the whole link group. If not, find the link to delete by its link_id,
send the DELETE_LINK response LLC message and then clear the deleted
link. Finally determine and update the link group state.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce a work that is scheduled when a new DELETE_LINK LLC request is
received. The work will call either the SMC client or SMC server
DELETE_LINK processing.
And use the LLC flow framework to process incoming DELETE_LINK LLC
messages, scheduling the llc_del_link_work for those events.
With these changes smc_lgr_forget() is only called by one function and
can be migrated into smc_lgr_cleanup_early().
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a link group moved from asymmetric to symmetric state then the
dangling asymmetric link can be deleted. Add smc_llc_find_asym_link() to
find the respective link and add smc_llc_delete_asym_link() to delete
it.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch finalizes the ADD_LINK processing of new links. Send the
CONFIRM_LINK request to the peer, receive the response and set link
state to ACTIVE.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Part of SMC server new link establishment is the exchange of rkeys for
used buffers.
Loop over all used RMB buffers and send ADD_LINK_CONTINUE LLC messages
to the peer.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
First set of functions to process an ADD_LINK LLC request as an SMC
server. Find an alternate IB device, determine the new link group type
and get the index for the new link. Then initialize the link and send
the ADD_LINK LLC message to the peer. Save the contents of the response,
ready the link, map all used buffers and register the buffers with the
IB device. If any error occurs, stop the processing and clear the link.
And call smc_llc_srv_add_link() in af_smc.c to start second link
establishment after the initial link of a link group was created.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch finalizes the ADD_LINK processing of new links. Receive the
CONFIRM_LINK request from peer, complete the link initialization,
register all used buffers with the IB device and finally send the
CONFIRM_LINK response, which completes the ADD_LINK processing.
And activate smc_llc_cli_add_link() in af_smc.c.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Part of the SMC client new link establishment process is the exchange of
rkeys for all used buffers.
Add new LLC message type ADD_LINK_CONTINUE which is used to exchange
rkeys of all current RMB buffers. Add functions to iterate over all
used RMB buffers of the link group, and implement the ADD_LINK_CONTINUE
processing.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
First set of functions to process an ADD_LINK LLC request as an SMC
client. Find an alternate IB device, determine the new link group type
and get the index for the new link. Then ready the link, map the buffers
and send an ADD_LINK LLC response. If any error occurs, send a reject
LLC message and terminate the processing.
Add smc_llc_alloc_alt_link() to find a free link index for a new link,
depending on the new link group type.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/smc/smc_llc.c:544:12: warning: ‘smc_llc_alloc_alt_link’ defined but not used [-Wunused-function]
static int smc_llc_alloc_alt_link(struct smc_link_group *lgr,
^~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce a work that is scheduled when a new ADD_LINK LLC request is
received. The work will call either the SMC client or SMC server
ADD_LINK processing.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add smc_llc_alloc_alt_link() to find a free link index for a new link,
depending on the new link group type. And update constants for the
maximum number of links to 3 (2 symmetric and 1 dangling asymmetric link).
These maximum numbers are the same as used by other implementations of the
SMC-R protocol.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the introduced link down processing in all places where the link
group is terminated and take down the affected link only.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce llc_conf_mutex in the link group which is used to protect the
buffers and lgr states against parallel link reconfiguration.
This ensures that new connections do not start to register buffers with
the links of a link group when link creation or termination is running.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All LLC sends are done from worker context only, so remove the prep
functions which were used to build the message before it was sent, and
add the function content into the respective send function
smc_llc_send_add_link() and smc_llc_send_delete_link().
Extend smc_llc_send_add_link() to include the qp_mtu value in the LLC
message, which is needed to establish a link after the initial link was
created. Extend smc_llc_send_delete_link() to contain a link_id and a
reason code for the link deletion in the LLC message, which is needed
when a specific link should be deleted.
And add the list of existing DELETE_LINK reason codes.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The connection layer in af_smc.c is now using the new LLC flow
framework, which made the link state DELETING obsolete. Remove the state
and the respective helpers.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The new SMC-R multiple link support will support a maximum of 3 links,
and one CONFIRM_RKEY LLC message can transport 3 rkeys of an rmb buffer.
There is no need for the LLC message type CONFIRM_RKEY_CONTINUE which is
needed when more than 3 rkeys per rmb buffer needs to be exchanged.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the LLC flow framework for the processing of DELETE_RKEY messages
that were received from the peer.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the LLC flow framework for the processing of CONFIRM_RKEY messages
that were received from the peer.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Get rid of the extra function and move the two-liner for the TEST_LINK
response processing into the event handler function.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adapt smc_llc_do_delete_rkey() to use the LLC flow and support multiple
links when deleting the rkeys for rmb buffers at the peer.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adapt smc_llc_do_confirm_rkey() to use the LLC flow and support the
rkeys of multiple links when the CONFIRM_RKEY LLC message is build.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change the code that processes the SMC client part of connection
establishment to use the LLC flow framework (CONFIRM_LINK request
messages).
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change the code that processes the SMC server part of connection
establishment to use the LLC flow framework (CONFIRM_LINK response
messages).
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce smc_llc_eval_conf_link() to evaluate the CONFIRM_LINK message
contents. This implements this logic at the LLC layer. The function will
be used by af_smc.c to process the received LLC layer messages.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce smc_llc_enqueue() to enqueue LLC messages, and adapt
smc_llc_rx_handler() to enqueue all received LLC messages.
smc_llc_enqueue() also makes it possible to enqueue LLC messages from
local code.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The new framework allows to start specific types of LLC control flows,
protects active flows and makes it possible to wait for flows to finish
before starting a new flow.
This mechanism is used for the LLC control layer to model flows like
'add link' or 'delete link' which need to send/receive several LLC
messages and are not allowed to get interrupted by the wrong type of
messages.
'Add link' or 'Delete link' messages arriving in the middle of a flow
are delayed and processed when the current flow finished.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce smc_llc_lgr_init() and smc_llc_lgr_clear() to implement all
llc layer specific initialization and cleanup in module smc_llc.c.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When llc responses are received then possible waiters for this response
are to be notified. This can be done in tasklet context, without to
use a work in the llc work queue. Move all code that handles llc
responses into smc_llc_rx_response().
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Incoming llc messages are processed in irq tasklet context, and
a worker is used to send outgoing messages. The worker is needed
because getting a send buffer could result in a wait for a free buffer.
To make sure all incoming llc messages are processed in a serialized way
introduce an event queue and create a new queue entry for each message
which is queued to this event queue. A new worker processes the event
queue entries in order.
And remove the use of a separate worker to send outgoing llc messages
because the messages are processed in worker context already.
With this event queue the serialized llc_wq work queue is obsolete,
remove it.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cancel the testlink worker during link clear processing and remove the
extra function smc_llc_link_inactive().
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The testlink work waits for a response to the testlink request and
blocks the single threaded llc_wq. This type of work does not have to be
serialized and can be moved to the system work queue.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Before a link can be reused it must have been cleared. Lowest current
link state is INACTIVE, which does not mean that the link is already
cleared.
Add a new state UNUSED that is set when the link is cleared and can be
reused.
Add helper smc_llc_usable_link() to find an active link in a link group,
and smc_link_usable() to determine if a link is usable.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Karsten Graul