Commit Graph

98 Commits

Author SHA1 Message Date
Håkon Bugge
126f760ca9 rds: Fix incorrect statistics counting
In rds_send_xmit() there is logic to batch the sends. However, if
another thread has acquired the lock and has incremented the send_gen,
it is considered a race and we yield. The code incrementing the
s_send_lock_queue_raced statistics counter did not count this event
correctly.

This commit counts the race condition correctly.

Changes from v1:
- Removed check for *someone_on_xmit()*
- Fixed incorrect indentation

Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Reviewed-by: Knut Omang <knut.omang@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-07 20:07:13 -07:00
Håkon Bugge
f530f39f5f rds: Fix non-atomic operation on shared flag variable
The bits in m_flags in struct rds_message are used for a plurality of
reasons, and from different contexts. To avoid any missing updates to
m_flags, use the atomic set_bit() instead of the non-atomic equivalent.

Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Reviewed-by: Knut Omang <knut.omang@oracle.com>
Reviewed-by: Wei Lin Guay <wei.lin.guay@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-05 14:49:49 -07:00
Håkon Bugge
e623a48ee4 rds: Make sure updates to cp_send_gen can be observed
cp->cp_send_gen is treated as a normal variable, although it may be
used by different threads.

This is fixed by using {READ,WRITE}_ONCE when it is incremented and
READ_ONCE when it is read outside the {acquire,release}_in_xmit
protection.

Normative reference from the Linux-Kernel Memory Model:

    Loads from and stores to shared (but non-atomic) variables should
    be protected with the READ_ONCE(), WRITE_ONCE(), and
    ACCESS_ONCE().

Clause 5.1.2.4/25 in the C standard is also relevant.

Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Reviewed-by: Knut Omang <knut.omang@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-20 15:33:01 -07:00
Sowmini Varadhan
69b92b5b74 rds: tcp: send handshake ping-probe from passive endpoint
The RDS handshake ping probe added by commit 5916e2c155
("RDS: TCP: Enable multipath RDS for TCP") is sent from rds_sendmsg()
before the first data packet is sent to a peer. If the conversation
is not bidirectional  (i.e., one side is always passive and never
invokes rds_sendmsg()) and the passive side restarts its rds_tcp
module, a new HS ping probe needs to be sent, so that the number
of paths can be re-established.

This patch achieves that by sending a HS ping probe from
rds_tcp_accept_one() when c_npaths is 0 (i.e., we have not done
a handshake probe with this peer yet).

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Tested-by: Jenny Xu <jenny.x.xu@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-22 11:34:04 -04:00
Sowmini Varadhan
00354de577 rds: tcp: various endian-ness fixes
Found when testing between sparc and x86 machines on different
subnets, so the address comparison patterns hit the corner cases and
brought out some bugs fixed by this patch.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Tested-by: Imanti Mendez <imanti.mendez@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16 12:45:15 -04:00
Avinash Repaka
f9fb69adb6 RDS: make message size limit compliant with spec
RDS support max message size as 1M but the code doesn't check this
in all cases. Patch fixes it for RDMA & non-RDMA and RDS MR size
and its enforced irrespective of underlying transport.

Signed-off-by: Avinash Repaka <avinash.repaka@oracle.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
2017-01-02 14:02:57 -08:00
Santosh Shilimkar
941f8d55f6 RDS: RDMA: Fix the composite message user notification
When application sends an RDS RDMA composite message consist of
RDMA transfer to be followed up by non RDMA payload, it expect to
be notified *only* when the full message gets delivered. RDS RDMA
notification doesn't behave this way though.

Thanks to Venkat for debug and root casuing the issue
where only first part of the message(RDMA) was
successfully delivered but remainder payload delivery failed.
In that case, application should not be notified with
a false positive of message delivery success.

Fix this case by making sure the user gets notified only after
the full message delivery.

Reviewed-by: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
2017-01-02 14:02:54 -08:00
Santosh Shilimkar
584a8279a4 RDS: RDMA: return appropriate error on rdma map failures
The first message to a remote node should prompt a new
connection even if it is RDMA operation. For RDMA operation
the MR mapping can fail because connections is not yet up.

Since the connection establishment is asynchronous,
we make sure the map failure because of unavailable
connection reach to the user by appropriate error code.
Before returning to the user, lets trigger the connection
so that its ready for the next retry.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
2017-01-02 14:02:46 -08:00
Santosh Shilimkar
bb7897631d RDS: mark few internal functions static to make sparse build happy
Fixes below warnings:
warning: symbol 'rds_send_probe' was not declared. Should it be static?
warning: symbol 'rds_send_ping' was not declared. Should it be static?
warning: symbol 'rds_tcp_accept_one_path' was not declared. Should it be static?
warning: symbol 'rds_walk_conn_path_info' was not declared. Should it be static?

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
2017-01-02 14:02:40 -08:00
Sowmini Varadhan
905dd4184e RDS: TCP: Track peer's connection generation number
The RDS transport has to be able to distinguish between
two types of failure events:
(a) when the transport fails (e.g., TCP connection reset)
    but the RDS socket/connection layer on both sides stays
    the same
(b) when the peer's RDS layer itself resets (e.g., due to module
    reload or machine reboot at the peer)
In case (a) both sides must reconnect and continue the RDS messaging
without any message loss or disruption to the message sequence numbers,
and this is achieved by rds_send_path_reset().

In case (b) we should reset all rds_connection state to the
new incarnation of the peer. Examples of state that needs to
be reset are next expected rx sequence number from, or messages to be
retransmitted to, the new incarnation of the peer.

To achieve this, the RDS handshake probe added as part of
commit 5916e2c155 ("RDS: TCP: Enable multipath RDS for TCP")
is enhanced so that sender and receiver of the RDS ping-probe
will add a generation number as part of the RDS_EXTHDR_GEN_NUM
extension header. Each peer stores local and remote generation
numbers as part of each rds_connection. Changes in generation
number will be detected via incoming handshake probe ping
request or response and will allow the receiver to reset rds_connection
state.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-17 13:35:18 -05:00
Sowmini Varadhan
5916e2c155 RDS: TCP: Enable multipath RDS for TCP
Use RDS probe-ping to compute how many paths may be used with
the peer, and to synchronously start the multiple paths. If mprds is
supported, hash outgoing traffic to one of multiple paths in rds_sendmsg()
when multipath RDS is supported by the transport.

CC: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-15 11:36:58 -07:00
Sowmini Varadhan
226f7a7d97 RDS: Rework path specific indirections
Refactor code to avoid separate indirections for single-path
and multipath transports. All transports (both single and mp-capable)
will get a pointer to the rds_conn_path, and can trivially derive
the rds_connection from the ->cp_conn.

Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-01 16:45:17 -04:00
Sowmini Varadhan
d769ef81d5 RDS: Update rds_conn_shutdown to work with rds_conn_path
This commit changes rds_conn_shutdown to take a rds_conn_path *
argument, allowing it to shutdown paths other than c_path[0] for
MP-capable transports.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:44 -07:00
Sowmini Varadhan
3c0a59001a RDS: Add rds_conn_path_connect_if_down() for MP-aware callers
rds_conn_path_connect_if_down() works on the rds_conn_path
that it is passed. Callers who are not t_m_capable may continue
calling rds_conn_connect_if_down, which will invoke
rds_conn_path_connect_if_down() with the default c_path[0].

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:43 -07:00
Sowmini Varadhan
45997e9e2e RDS: Make rds_send_pong() take a rds_conn_path argument
This commit allows rds_send_pong() callers to send back
the rds pong message on some path other than c_path[0] by
passing in a struct rds_conn_path * argument.  It also
removes the last dependency on the #defines in rds_single.h
from send.c

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:43 -07:00
Sowmini Varadhan
01ff34ed44 RDS: Extract rds_conn_path from i_conn_path in rds_send_drop_to() for MP-capable transports
Explicitly set up rds_conn_path, either from i_conn_path (for
MP capable transpots) or as c_path[0], and use this in
rds_send_drop_to()

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:43 -07:00
Sowmini Varadhan
1f9ecd7eac RDS: Pass rds_conn_path to rds_send_xmit()
Pass a struct rds_conn_path to rds_send_xmit so that MP capable
transports can transmit packets on something other than c_path[0].
The eventual goal for MP capable transports is to hash the rds
socket to a path based on the bound local address/port, and use
this path as the argument to rds_send_xmit()

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:43 -07:00
Sowmini Varadhan
780a6d9e16 RDS: Make rds_send_queue_rm() rds_conn_path aware
Pass the rds_conn_path to rds_send_queue_rm, and use it to initialize
the i_conn_path field in struct rds_incoming. This commit also makes
rds_send_queue_rm() MP capable, because it now takes locks
specific to the rds_conn_path passed in, instead of defaulting to
the c_path[0] based defines from rds_single_path.h

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:42 -07:00
Sowmini Varadhan
7d885d0fc6 RDS: Remove stale function rds_send_get_message()
The only caller of rds_send_get_message() was
rds_iw_send_cq_comp_handler() which was removed as part of
commit dcdede0406 ("RDS: Drop stale iWARP RDMA transport"),
so remove rds_send_get_message() for the same reason.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:42 -07:00
Sowmini Varadhan
5c3d274c75 RDS: Add rds_send_path_drop_acked()
rds_send_path_drop_acked() is the path-specific version of
rds_send_drop_acked() to be invoked by MP capable callers.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:42 -07:00
Sowmini Varadhan
4e9b551c14 RDS: Add rds_send_path_reset()
rds_send_path_reset() is the path specific version of rds_send_reset()
intended for MP capable callers.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:42 -07:00
Sowmini Varadhan
0cb43965d4 RDS: split out connection specific state from rds_connection to rds_conn_path
In preparation for multipath RDS, split the rds_connection
structure into a base structure, and a per-path struct rds_conn_path.
The base structure tracks information and locks common to all
paths. The workqs for send/recv/shutdown etc are tracked per
rds_conn_path. Thus the workq callbacks now work with rds_conn_path.

This commit allows for one rds_conn_path per rds_connection, and will
be extended into multiple conn_paths in  subsequent commits.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 23:50:41 -07:00
Sowmini Varadhan
0b6f760cff RDS: TCP: Retransmit half-sent datagrams when switching sockets in rds_tcp_reset_callbacks
When we switch a connection's sockets in rds_tcp_rest_callbacks,
any partially sent datagram must be retransmitted on the new
socket so that the receiver can correctly reassmble the RDS
datagram. Use rds_send_reset() which is designed for this purpose.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 15:10:15 -07:00
Quentin Casasnovas
8c7188b234 RDS: fix race condition when sending a message on unbound socket
Sasha's found a NULL pointer dereference in the RDS connection code when
sending a message to an apparently unbound socket.  The problem is caused
by the code checking if the socket is bound in rds_sendmsg(), which checks
the rs_bound_addr field without taking a lock on the socket.  This opens a
race where rs_bound_addr is temporarily set but where the transport is not
in rds_bind(), leading to a NULL pointer dereference when trying to
dereference 'trans' in __rds_conn_create().

Vegard wrote a reproducer for this issue, so kindly ask him to share if
you're interested.

I cannot reproduce the NULL pointer dereference using Vegard's reproducer
with this patch, whereas I could without.

Complete earlier incomplete fix to CVE-2015-6937:

  74e98eb085 ("RDS: verify the underlying transport exists before creating a connection")

Cc: David S. Miller <davem@davemloft.net>
Cc: stable@vger.kernel.org

Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com>
Reviewed-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-24 17:20:09 -05:00
santosh.shilimkar@oracle.com
7b4b000951 RDS: fix rds-ping deadlock over TCP transport
Sowmini found hang with rds-ping while testing RDS over TCP. Its
a corner case and doesn't happen always. The issue is not reproducible
with IB transport. Its clear from below dump why we see it with RDS TCP.

 [<ffffffff8153b7e5>] do_tcp_setsockopt+0xb5/0x740
 [<ffffffff8153bec4>] tcp_setsockopt+0x24/0x30
 [<ffffffff814d57d4>] sock_common_setsockopt+0x14/0x20
 [<ffffffffa096071d>] rds_tcp_xmit_prepare+0x5d/0x70 [rds_tcp]
 [<ffffffffa093b5f7>] rds_send_xmit+0xd7/0x740 [rds]
 [<ffffffffa093bda2>] rds_send_pong+0x142/0x180 [rds]
 [<ffffffffa0939d34>] rds_recv_incoming+0x274/0x330 [rds]
 [<ffffffff810815ae>] ? ttwu_queue+0x11e/0x130
 [<ffffffff814dcacd>] ? skb_copy_bits+0x6d/0x2c0
 [<ffffffffa0960350>] rds_tcp_data_recv+0x2f0/0x3d0 [rds_tcp]
 [<ffffffff8153d836>] tcp_read_sock+0x96/0x1c0
 [<ffffffffa0960060>] ? rds_tcp_recv_init+0x40/0x40 [rds_tcp]
 [<ffffffff814d6a90>] ? sock_def_write_space+0xa0/0xa0
 [<ffffffffa09604d1>] rds_tcp_data_ready+0xa1/0xf0 [rds_tcp]
 [<ffffffff81545249>] tcp_data_queue+0x379/0x5b0
 [<ffffffffa0960cdb>] ? rds_tcp_write_space+0xbb/0x110 [rds_tcp]
 [<ffffffff81547fd2>] tcp_rcv_established+0x2e2/0x6e0
 [<ffffffff81552602>] tcp_v4_do_rcv+0x122/0x220
 [<ffffffff81553627>] tcp_v4_rcv+0x867/0x880
 [<ffffffff8152e0b3>] ip_local_deliver_finish+0xa3/0x220

This happens because rds_send_xmit() chain wants to take
sock_lock which is already taken by tcp_v4_rcv() on its
way to rds_tcp_data_ready(). Commit db6526dcb5 ("RDS: use
rds_send_xmit() state instead of RDS_LL_SEND_FULL") which
was trying to opportunistically finish the send request
in same thread context.

But because of above recursive lock hang with RDS TCP,
the send work from rds_send_pong() needs to deferred to
worker to avoid lock up. Given RDS ping is more of connectivity
test than performance critical path, its should be ok even
for transport like IB.

Reported-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by:  Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Acked-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-18 22:45:55 -07:00
Santosh Shilimkar
0c28c04500 RDS: IB: split send completion handling and do batch ack
Similar to what we did with receive CQ completion handling, we split
the transmit completion handler so that it lets us implement batched
work completion handling.

We re-use the cq_poll routine and makes use of RDS_IB_SEND_OP to
identify the send vs receive completion event handler invocation.

Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
2015-10-05 11:19:01 -07:00
Santosh Shilimkar
db6526dcb5 RDS: use rds_send_xmit() state instead of RDS_LL_SEND_FULL
In Transport indepedent rds_sendmsg(), we shouldn't make decisions based
on RDS_LL_SEND_FULL which is used to manage the ring for RDMA based
transports. We can safely issue rds_send_xmit() and the using its
return value take decision on deferred work. This will also fix
the scenario where at times we are seeing connections stuck with
the LL_SEND_FULL bit getting set and never cleared.

We kick krdsd after any time we see -ENOMEM or -EAGAIN from the
ring allocation code.

Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
2015-10-05 11:19:01 -07:00
Santosh Shilimkar
4bebdd7a4d RDS: defer the over_batch work to send worker
Current process gives up if its send work over the batch limit.
The work queue will get  kicked to finish off any other requests.
This fixes remainder condition from commit 443be0e5af ("RDS: make
sure not to loop forever inside rds_send_xmit").

The restart condition is only for the case where we reached to
over_batch code for some other reason so just retrying again
before giving up.

While at it, make sure we use already available 'send_batch_count'
parameter instead of magic value. The batch count threshold value
of 1024 came via commit 443be0e5af ("RDS: make sure not to loop
forever inside rds_send_xmit"). The idea is to process as big a
batch as we can but at the same time we don't hold other waiting
processes for send. Hence back-off after the send_batch_count
limit (1024) to avoid soft-lock ups.

Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
2015-10-05 11:18:45 -07:00
Mukesh Kacker
06e8941e22 RDS: return EMSGSIZE for oversize requests before processing/queueing
rds_send_queue_rm() allows for the "current datagram" being queued
to exceed SO_SNDBUF thresholds by checking bytes queued without
counting in length of current datagram. (Since sk_sndbuf is set
to twice requested SO_SNDBUF value as a kernel heuristic this
is usually fine!)

If this "current datagram" squeezing past the threshold is itself
many times the size of the sk_sndbuf threshold itself then even
twice the SO_SNDBUF does not save us and it gets queued but
cannot be transmitted. Threads block and deadlock and device
becomes unusable. The check for this datagram not exceeding
SNDBUF thresholds (EMSGSIZE) is not done on this datagram as
that check is only done if queueing attempt fails.
(Datagrams that follow this datagram fail queueing attempts, go
through the check and eventually trip EMSGSIZE error but zero
length datagrams silently fail!)

This fix moves the check for datagrams exceeding SNDBUF limits
before any processing or queueing is attempted and returns EMSGSIZE
early in the rds_sndmsg() code. This change also ensures that all
datagrams get checked for exceeding SNDBUF/sk_sndbuf size limits
and the large datagrams that exceed those limits do not get to
rds_send_queue_rm() code for processing.

Signed-off-by: Mukesh Kacker <mukesh.kacker@oracle.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-25 13:35:31 -07:00
santosh.shilimkar@oracle.com
dfcec251d2 RDS: make sure rds_send_drop_to properly takes the m_rs_lock
rds_send_drop_to() is used during socket tear down to find all the
messages on the socket and flush them .  It can race with the
acking code unless it takes the m_rs_lock on each and every message.

This plugs a hole where we didn't take m_rs_lock on any message that
didn't have the RDS_MSG_ON_CONN set.  Taking m_rs_lock avoids
double frees and other memory corruptions as the ack code trusts
the message m_rs pointer on a socket that had actually been freed.

We must take m_rs_lock to access m_rs.  Because of lock nesting and
rs access, we also need to acquire rs_lock.

Reviewed-by: Ajaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-25 13:35:31 -07:00
santosh.shilimkar@oracle.com
4f73113c63 RDS: Mark message mapped before transmit
rds_send_xmit() marks the rds message map flag after
xmit_[rdma/atomic]() which is clearly wrong.  We need
to maintain the ownership between transport and rds.

Also take care of error path.

Reviewed-by: Ajaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-25 13:35:30 -07:00
santosh.shilimkar@oracle.com
0c48424021 RDS: check for congestion updates during rds_send_xmit
Ensure we don't keep sending the data if the link is congested.

Reviewed-by: Ajaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-25 13:35:30 -07:00
Sowmini Varadhan
d5a8ac28a7 RDS-TCP: Make RDS-TCP work correctly when it is set up in a netns other than init_net
Open the sockets calling sock_create_kern() with the correct struct net
pointer, and use that struct net pointer when verifying the
address passed to rds_bind().

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-07 11:29:57 -07:00
David S. Miller
87ffabb1f0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The dwmac-socfpga.c conflict was a case of a bug fix overlapping
changes in net-next to handle an error pointer differently.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-14 15:44:14 -04:00
Sowmini Varadhan
443be0e5af RDS: make sure not to loop forever inside rds_send_xmit
If a determined set of concurrent senders keep the send queue full,
we can loop forever inside rds_send_xmit.  This fix has two parts.

First we are dropping out of the while(1) loop after we've processed a
large batch of messages.

Second we add a generation number that gets bumped each time the
xmit bit lock is acquired.  If someone else has jumped in and
made progress in the queue, we skip our goto restart.

Original patch by Chris Mason.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-08 15:17:32 -04:00
Ying Xue
1b78414047 net: Remove iocb argument from sendmsg and recvmsg
After TIPC doesn't depend on iocb argument in its internal
implementations of sendmsg() and recvmsg() hooks defined in proto
structure, no any user is using iocb argument in them at all now.
Then we can drop the redundant iocb argument completely from kinds of
implementations of both sendmsg() and recvmsg() in the entire
networking stack.

Cc: Christoph Hellwig <hch@lst.de>
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-02 13:06:31 -05:00
Gu Zheng
f95b414edb net: introduce helper macro for_each_cmsghdr
Introduce helper macro for_each_cmsghdr as a wrapper of the enumerating
cmsghdr from msghdr, just cleanup.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-10 22:41:55 -05:00
Al Viro
c0371da604 put iov_iter into msghdr
Note that the code _using_ ->msg_iter at that point will be very
unhappy with anything other than unshifted iovec-backed iov_iter.
We still need to convert users to proper primitives.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-09 16:29:03 -05:00
Al Viro
083735f4b0 rds: switch rds_message_copy_from_user() to iov_iter
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-24 05:16:43 -05:00
Herton R. Krzesinski
593cbb3ec6 net/rds: fix possible double free on sock tear down
I got a report of a double free happening at RDS slab cache. One
suspicion was that may be somewhere we were doing a sock_hold/sock_put
on an already freed sock. Thus after providing a kernel with the
following change:

 static inline void sock_hold(struct sock *sk)
 {
-       atomic_inc(&sk->sk_refcnt);
+       if (!atomic_inc_not_zero(&sk->sk_refcnt))
+               WARN(1, "Trying to hold sock already gone: %p (family: %hd)\n",
+                       sk, sk->sk_family);
 }

The warning successfuly triggered:

Trying to hold sock already gone: ffff81f6dda61280 (family: 21)
WARNING: at include/net/sock.h:350 sock_hold()
Call Trace:
<IRQ>  [<ffffffff8adac135>] :rds:rds_send_remove_from_sock+0xf0/0x21b
[<ffffffff8adad35c>] :rds:rds_send_drop_acked+0xbf/0xcf
[<ffffffff8addf546>] :rds_rdma:rds_ib_recv_tasklet_fn+0x256/0x2dc
[<ffffffff8009899a>] tasklet_action+0x8f/0x12b
[<ffffffff800125a2>] __do_softirq+0x89/0x133
[<ffffffff8005f30c>] call_softirq+0x1c/0x28
[<ffffffff8006e644>] do_softirq+0x2c/0x7d
[<ffffffff8006e4d4>] do_IRQ+0xee/0xf7
[<ffffffff8005e625>] ret_from_intr+0x0/0xa
<EOI>

Looking at the call chain above, the only way I think this would be
possible is if somewhere we already released the same socket->sock which
is assigned to the rds_message at rds_send_remove_from_sock. Which seems
only possible to happen after the tear down done on rds_release.

rds_release properly calls rds_send_drop_to to drop the socket from any
rds_message, and some proper synchronization is in place to avoid race
with rds_send_drop_acked/rds_send_remove_from_sock. However, I still see
a very narrow window where it may be possible we touch a sock already
released: when rds_release races with rds_send_drop_acked, we check
RDS_MSG_ON_CONN to avoid cleanup on the same rds_message, but in this
specific case we don't clear rm->m_rs. In this case, it seems we could
then go on at rds_send_drop_to and after it returns, the sock is freed
by last sock_put on rds_release, with concurrently we being at
rds_send_remove_from_sock; then at some point in the loop at
rds_send_remove_from_sock we process an rds_message which didn't have
rm->m_rs unset for a freed sock, and a possible sock_hold on an sock
already gone at rds_release happens.

This hopefully address the described condition above and avoids a double
free on "second last" sock_put. In addition, I removed the comment about
socket destruction on top of rds_send_drop_acked: we call rds_send_drop_to
in rds_release and we should have things properly serialized there, thus
I can't see the comment being accurate there.

Signed-off-by: Herton R. Krzesinski <herton@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-03 12:52:00 -07:00
Peter Zijlstra
4e857c58ef arch: Mass conversion of smp_mb__*()
Mostly scripted conversion of the smp_mb__* barriers.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-18 14:20:48 +02:00
Steffen Hurrle
342dfc306f net: add build-time checks for msg->msg_name size
This is a follow-up patch to f3d3342602 ("net: rework recvmsg
handler msg_name and msg_namelen logic").

DECLARE_SOCKADDR validates that the structure we use for writing the
name information to is not larger than the buffer which is reserved
for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR
consistently in sendmsg code paths.

Signed-off-by: Steffen Hurrle <steffen@hurrle.net>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-18 23:04:16 -08:00
jeff.liu
5175a5e76b RDS: fix rds-ping spinlock recursion
This is the revised patch for fixing rds-ping spinlock recursion
according to Venkat's suggestions.

RDS ping/pong over TCP feature has been broken for years(2.6.39 to
3.6.0) since we have to set TCP cork and call kernel_sendmsg() between
ping/pong which both need to lock "struct sock *sk". However, this
lock has already been hold before rds_tcp_data_ready() callback is
triggerred. As a result, we always facing spinlock resursion which
would resulting in system panic.

Given that RDS ping is only used to test the connectivity and not for
serious performance measurements, we can queue the pong transmit to
rds_wq as a delayed response.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
CC: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
CC: David S. Miller <davem@davemloft.net>
CC: James Morris <james.l.morris@oracle.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-09 13:57:23 -04:00
Dave Jones
a6506e1486 Remove printk from rds_sendmsg
no socket layer outputs a message for this error and neither should rds.

Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-20 16:12:11 -04:00
Paul Gortmaker
bc3b2d7fb9 net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules
These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:30 -04:00
Paul Gortmaker
d9b9384215 net: add moduleparam.h for users of module_param/MODULE_PARM_DESC
These files were getting access to these two via the implicit
presence of module.h everywhere.  They aren't modules, so they
don't need the full module.h inclusion though.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:29 -04:00
Manuel Zerpies
cb0a605649 net/rds: use prink_ratelimited() instead of printk_ratelimit()
Since printk_ratelimit() shouldn't be used anymore (see comment in
include/linux/printk.h), replace it with printk_ratelimited()

Signed-off-by: Manuel Zerpies <manuel.f.zerpies@ww.stud.uni-erlangen.de>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>
2011-06-17 00:03:03 -04:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Andy Grover
d139ff0907 RDS: Let rds_message_alloc_sgs() return NULL
Even with the previous fix, we still are reading the iovecs once
to determine SGs needed, and then again later on. Preallocating
space for sg lists as part of rds_message seemed like a good idea
but it might be better to not do this. While working to redo that
code, this patch attempts to protect against userspace rewriting
the rds_iovec array between the first and second accesses.

The consequences of this would be either a too-small or too-large
sg list array. Too large is not an issue. This patch changes all
callers of message_alloc_sgs to handle running out of preallocated
sgs, and fail gracefully.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-30 16:34:18 -07:00
stephen hemminger
ff51bf8415 rds: make local functions/variables static
The RDS protocol has lots of functions that should be
declared static. rds_message_get/add_version_extension is
removed since it defined but never used.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-21 04:26:39 -07:00