Always set a reason_code when smc_conn_create() returns an error code.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SMC handles deferred work in tasklets. As tasklets cannot sleep this
can result in rare EBUSY conditions, so defer this work in a work queue.
The high level api functions do not defer work because they can sleep
until the llc send is actually completed.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the llc layer specific initialization and cleanup out of smc_core.c
into smc_llc.c (smc_llc_link_init and smc_llc_link_clear). Move all
initialization of a link into the new init function.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make smc_llc_send_test_link() static and remove it from the header file.
And to send a test_link response set the response flag and send the
message back as-is, without using smc_llc_send_test_link(). And because
smc_llc_send_test_link() must no longer send responses, remove the
response flag handling from the function.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove an unneeded (void *) cast from the calls to
smc_llc_send_message(). No functional changes.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Register new rmb buffers with the remote peer by exchanging a
confirm_rkey llc message.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If TCP_NODELAY is set or TCP_CORK is reset, setsockopt triggers the
tx worker. This does not make sense, if the SMC socket switched to
the TCP fallback when the connection is created. This patch adds
the additional check for the fallback case.
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Provide an implementation for splice() when we are using SMC. See
smc_splice_read() for further details.
Signed-off-by: NStefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com><
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Preparatory work for splice() support.
Signed-off-by: NStefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com><
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Turn smc_rx_wait_data into a generic function that can be used at various
instances to wait on traffic to complete with varying criteria.
Signed-off-by: NStefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com><
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some of the conditions to exit recv() are common in two pathes - cleaning up
code by moving the check up so we have it only once.
Signed-off-by: NStefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com><
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sendpage() call grabs the sock lock before calling the default
implementation - which tries to grab it once again.
Signed-off-by: NStefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com><
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When smc_wr_reg_send() fails then tag (regerr) the affected buffer and
free it in smc_buf_unuse().
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Consolidate the call to smc_wr_reg_send() in a new function.
No functional changes.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

An SMC link group is bound to a specific vlan_id. Its link uses
the RoCE-GIDs established for the specific vlan_id. This patch makes
sure the appropriate vlan_id is determined for stacked scenarios like
for instance a master bonding device with vlan devices enslaved.
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SIOCINQ returns the amount of unread data in the RMB.
SIOCOUTQ returns the amount of unsent or unacked sent data in the send
buffer.
SIOCOUTQNSD returns the amount of data prepared for sending, but
not yet sent.
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Update smc_diag.c to support ipv6 addresses on the diagnosis interface.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add periodic LLC testlink support to ensure the link is still active.
The interval time is initialized using the value of
sysctl_tcp_keepalive_time.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The smc_poll code tries to finish connect() if the socket is in
state SMC_INIT and polling of the internal CLC-socket returns with
EPOLLOUT. This makes sense for a select/poll call following a connect
call, but not without preceding connect().
With this patch smc_poll starts connect logic only, if the CLC-socket
is no longer in its initial state TCP_CLOSE.

In addition, a poll error on the internal CLC-socket is always
propagated to the SMC socket.

With this patch the code path mentioned by syzbot
https://syzkaller.appspot.com/bug?extid=03faa2dc16b8b64be396
is no longer possible.
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Reported-by: syzbot+03faa2dc16b8b64be396@syzkaller.appspotmail.com
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If sockopt TCP_DEFER_ACCEPT is set, the accept is delayed till
data is available.
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Setting sockopt TCP_NODELAY or resetting sockopt TCP_CORK
triggers data transfer.

For a corked SMC socket RDMA writes are deferred, if there is
still sufficient send buffer space available.
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Several TCP sockopts do not work for SMC. One example are the
TCP_FASTOPEN sockopts, since SMC-connection setup is based on the TCP
three-way-handshake.
If the SMC socket is still in state SMC_INIT, such sockopts trigger
fallback to TCP. Otherwise an error is returned.
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The struct smc_cdc_msg must be defined as packed so the
size is 44 bytes.
And change the structure size check so sizeof is checked.
Signed-off-by: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The internal CLC socket should exist till the SMC-socket is released.
Function tcp_listen_worker() releases the internal CLC socket of a
listen socket, if an smc_close_active() is called. This function
is called for the final release(), but it is called for shutdown
SHUT_RDWR as well. This opens a door for protection faults, if
socket calls using the internal CLC socket are called for a
shutdown listen socket.

With the changes of
commit 3d502067 ("net/smc: simplify wait when closing listen socket")
there is no need anymore to release the internal CLC socket in
function tcp_listen_worker((). It is sufficient to release it in
smc_release().

Fixes: 127f4970 ("net/smc: release clcsock from tcp_listen_worker")
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Reported-by: syzbot+9045fc589fcd196ef522@syzkaller.appspotmail.com
Reported-by: syzbot+28a2c86cf19c81d871fa@syzkaller.appspotmail.com
Reported-by: syzbot+9605e6cace1b5efd4a0a@syzkaller.appspotmail.com
Reported-by: syzbot+cf9012c597c8379d535c@syzkaller.appspotmail.com
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Calling shutdown with SHUT_RD and SHUT_RDWR for a listening SMC socket
crashes, because
   commit 127f4970 ("net/smc: release clcsock from tcp_listen_worker")
releases the internal clcsock in smc_close_active() and sets smc->clcsock
to NULL.
For SHUT_RD the smc_close_active() call is removed.
For SHUT_RDWR the kernel_sock_shutdown() call is omitted, since the
clcsock is already released.

Fixes: 127f4970 ("net/smc: release clcsock from tcp_listen_worker")
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Reported-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Not every CLC proposal message needs the maximum buffer length.
Due to the MSG_WAITALL flag, it is important to use the peeked
real length when receiving the message.

Fixes: d63d271c ("smc: switch to sock_recvmsg()")
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add ipv6 support to the smc socket layer functions. Make use of the
updated clc layer functions to retrieve and match ipv6 information.
The indicator for ipv4 or ipv6 is the protocol constant that is provided
in the socket() call with address family AF_SMC.
Based-on-patch-by: NTakanori Ueda <tkueda@jp.ibm.com>
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The CLC layer is updated to support ipv6 proposal messages from peers and
to match incoming proposal messages against the ipv6 addresses of the net
device. struct smc_clc_ipv6_prefix is updated to provide the space for an
ipv6 address (struct was not used before). SMC_CLC_MAX_LEN is updated to
include the size of the proposal prefix. Existing code in net is not
affected, the previous SMC_CLC_MAX_LEN value is large enough to hold ipv4
proposal messages.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce functions smc_clc_prfx_set to retrieve IP information for the
CLC proposal msg and smc_clc_prfx_match to match the contents of a
proposal message against the IP addresses of the net device. The new
functions replace the functionality provided by smc_clc_netinfo_by_tcpsk,
which is removed by this patch. The match functionality is extended to
scan all ipv4 addresses of the net device for a match against the
ipv4 subnet from the proposal msg.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Closing of a listen socket wakes up kernel_accept() of
smc_tcp_listen_worker(), and then has to wait till smc_tcp_listen_worker()
gives up the internal clcsock. The wait logic introduced with
commit 127f4970 ("net/smc: release clcsock from tcp_listen_worker")
might wait longer than necessary. This patch implements the idea to
implement the wait just with flush_work(), and gets rid of the extra
smc_close_wait_listen_clcsock() function.

Fixes: 127f4970 ("net/smc: release clcsock from tcp_listen_worker")
Reported-by: NHans Wippel <hwippel@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The free_work worker must be scheduled when the link group is
abnormally terminated.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make sure there is no pending or running free_work worker for the link
group when freeing the link group.
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

smc allocates a certain number of CQ entries for used RoCE devices. For
mlx5 devices the chosen constant number results in a large allocation
causing this warning:

[13355.124656] WARNING: CPU: 3 PID: 16535 at mm/page_alloc.c:3883 __alloc_pages_nodemask+0x2be/0x10c0
[13355.124657] Modules linked in: smc_diag(O) smc(O) xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp bridge stp llc ip6table_filter ip6_tables iptable_filter mlx5_ib ib_core sunrpc mlx5_core s390_trng rng_core ghash_s390 prng aes_s390 des_s390 des_generic sha512_s390 sha256_s390 sha1_s390 sha_common ptp pps_core eadm_sch dm_multipath dm_mod vhost_net tun vhost tap sch_fq_codel kvm ip_tables x_tables autofs4 [last unloaded: smc]
[13355.124672] CPU: 3 PID: 16535 Comm: kworker/3:0 Tainted: G           O    4.14.0uschi #1
[13355.124673] Hardware name: IBM 3906 M04 704 (LPAR)
[13355.124675] Workqueue: events smc_listen_work [smc]
[13355.124677] task: 00000000e2f22100 task.stack: 0000000084720000
[13355.124678] Krnl PSW : 0704c00180000000 000000000029da76 (__alloc_pages_nodemask+0x2be/0x10c0)
[13355.124681]            R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3
[13355.124682] Krnl GPRS: 0000000000000000 00550e00014080c0 0000000000000000 0000000000000001
[13355.124684]            000000000029d8b6 00000000f3bfd710 0000000000000000 00000000014080c0
[13355.124685]            0000000000000009 00000000ec277a00 0000000000200000 0000000000000000
[13355.124686]            0000000000000000 00000000000001ff 000000000029d8b6 0000000084723720
[13355.124708] Krnl Code: 000000000029da6a: a7110200		tmll	%r1,512
                          000000000029da6e: a774ff29		brc	7,29d8c0
                         #000000000029da72: a7f40001		brc	15,29da74
                         >000000000029da76: a7f4ff25		brc	15,29d8c0
                          000000000029da7a: a7380000		lhi	%r3,0
                          000000000029da7e: a7f4fef1		brc	15,29d860
                          000000000029da82: 5820f0c4		l	%r2,196(%r15)
                          000000000029da86: a53e0048		llilh	%r3,72
[13355.124720] Call Trace:
[13355.124722] ([<000000000029d8b6>] __alloc_pages_nodemask+0xfe/0x10c0)
[13355.124724]  [<000000000013bd1e>] s390_dma_alloc+0x6e/0x148
[13355.124733]  [<000003ff802eeba6>] mlx5_dma_zalloc_coherent_node+0x8e/0xe0 [mlx5_core]
[13355.124740]  [<000003ff802eee18>] mlx5_buf_alloc_node+0x70/0x108 [mlx5_core]
[13355.124744]  [<000003ff804eb410>] mlx5_ib_create_cq+0x558/0x898 [mlx5_ib]
[13355.124749]  [<000003ff80407d40>] ib_create_cq+0x48/0x88 [ib_core]
[13355.124751]  [<000003ff80109fba>] smc_ib_setup_per_ibdev+0x52/0x118 [smc]
[13355.124753]  [<000003ff8010bcb6>] smc_conn_create+0x65e/0x728 [smc]
[13355.124755]  [<000003ff801081a2>] smc_listen_work+0x2d2/0x540 [smc]
[13355.124756]  [<0000000000162c66>] process_one_work+0x1be/0x440
[13355.124758]  [<0000000000162f40>] worker_thread+0x58/0x458
[13355.124759]  [<0000000000169e7e>] kthread+0x14e/0x168
[13355.124760]  [<00000000009ce8be>] kernel_thread_starter+0x6/0xc
[13355.124762]  [<00000000009ce8b8>] kernel_thread_starter+0x0/0xc
[13355.124762] Last Breaking-Event-Address:
[13355.124764]  [<000000000029da72>] __alloc_pages_nodemask+0x2ba/0x10c0
[13355.124764] ---[ end trace 34be38b581c0b585 ]---

This patch reduces the smc constant for the maximum number of allocated
completion queue entries SMC_MAX_CQE by 2 to avoid high round up values
in the mlx5 code, and reduces the number of allocated completion queue
entries even more, if the final allocation for an mlx5 device hits the
MAX_ORDER limit.
Reported-by: NIhnken Menssen <menssen@de.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the processing of a DELETE LINK message has started,
new connections should not be added to the link group that
is about to terminate.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add initial support for the LLC messages ADD LINK and DELETE LINK.
Introduce a link state field. Extend the initial LLC handshake with
ADD LINK processing.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SMC does not support eyecatchers in RMB elements,
decline peers requesting this support.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Process and respond to CONFIRM RKEY and DELETE RKEY messages.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add TEST LINK message responses, which also serves as preparation for
support of sockopt TCP_KEEPALIVE.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The daddr field holds the destination IPv4 address. The field was set but
never used and can be removed. The addr field was a left-over from an
earlier version of non-blocking connects and can be removed.
The result of the call to kernel_getpeername is not used, the call can be
removed. Non-blocking connects are working, so remove restriction comment.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The function smc_netinfo_by_tcpsk() belongs to CLC handling.
Move it to smc_clc.c and rename to smc_clc_netinfo_by_tcpsk.
Signed-off-by: NKarsten Graul <kgraul@linux.vnet.ibm.com>
Signed-off-by: NUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>