r_m_copy_from_user used to allocate the rm as well as kernel
buffers for the data, and then copy the data in. Now, sendmsg()
allocates the rm, although the data buffer alloc still happens
in r_m_copy_from_user.

SGs are still allocated with rm, but now r_m_alloc_sgs() is
used to reserve them. This allows multiple SG lists to be
allocated from the one rm -- this is important once we also
want to alloc our rdma sgl from this pool.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>

First, it looks to me like the atomic_inc is wrong.
We should be decrementing refcount only once here, no? It's
already being done by the mr_put() at the end.

Second, simplify the logic a bit by bailing early (with a warning)
if !mr.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>

Clearly separate rdma-related variables in rm from data-related ones.
This is in anticipation of adding atomic support.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>

Favor "if (foo)" style over "if (foo != NULL)".
Signed-off-by: NAndy Grover <andy.grover@oracle.com>

This fits better in connection.c, rather than threads.c.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>

Do not nest m_rs_lock under c_lock

Disable interrupts in {rdma,atomic}_send_complete
Signed-off-by: NAndy Grover <andy.grover@oracle.com>

This function has been the source of numerous bugs; it's just
too complicated. Simplified to nest spinlocks cleanly within
the second loop body, and kick out early if there are no
rms to drop.

This will be a little slower because conn lock is grabbed for
each entry instead of "caching" the lock across rms, but this
should be entirely irrelevant to fastpath performance.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>

On second look at this bug (OFED #2002), it seems that the
collision is not with the retransmission queue (packet acked
by the peer), but with the local send completion.  A theoretical
sequence of events (from time t0 to t3) is thought to be as
follows,

Thread #1
t0:
    sock_release
    rds_release
    rds_send_drop_to /* wait on send completion */
t2:
    rds_rdma_drop_keys()   /* destroy & free all mrs */

Thread #2
t1:
    rds_ib_send_cq_comp_handler
    rds_ib_send_unmap_rm
    rds_message_unmapped   /* wake up #1 @ t0 */
t3:
    rds_message_put
    rds_message_purge
    rds_mr_put   /* memory corruption detected */

The problem with the rds_rdma_drop_keys() is it could
remove a mr's refcount more than its due (i.e. repeatedly
as long as it still remains in the tree (mr->r_refcount > 0)).
Theoretically it should remove only one reference - reference
by the tree.

        /* Release any MRs associated with this socket */
        while ((node = rb_first(&rs->rs_rdma_keys))) {
                mr = container_of(node, struct rds_mr, r_rb_node);
                if (mr->r_trans == rs->rs_transport)
                        mr->r_invalidate = 0;
                rds_mr_put(mr);
        }

I think the correct way of doing it is to remove the mr from
the tree and rds_destroy_mr it first, then a rds_mr_put()
to decrement its reference count by one.  Whichever thread
holds the last reference will free the mr via rds_mr_put().
Signed-off-by: NTina Yang <tina.yang@oracle.com>
Signed-off-by: NAndy Grover <andy.grover@oracle.com>

in_interrupt() is true in softirqs. The BUG_ONs are supposed
to check for if irqs are disabled, so we should use
BUG_ON(irqs_disabled()) instead, duh.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>

struct rds_rdma_notify contains a 32 bits hole on 64bit arches,
make sure it is zeroed before copying it to user.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Andy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a mutex_unlock missing on the error path.  In each case, whenever the
label out is reached from elsewhere in the function, mutex is not locked.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E1;
@@

* mutex_lock(E1);
  <+... when != E1
  if (...) {
    ... when != E1
*   return ...;
  }
  ...+>
* mutex_unlock(E1);
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Reviewed-by: NZach Brown <zach.brown@oracle.com>
Acked-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Also added an explicit break; to avoid
a fallthrough in net/ipv4/tcp_input.c
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the original code, the "goto out" calls "rdma_destroy_id(cm_id);"
That isn't needed here and would cause problems because "cm_id" is an
ERR_PTR.  The new code just returns directly.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Acked-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Define a new function to return the waitqueue of a "struct sock".

static inline wait_queue_head_t *sk_sleep(struct sock *sk)
{
	return sk->sk_sleep;
}

Change all read occurrences of sk_sleep by a call to this function.

Needed for a future RCU conversion. sk_sleep wont be a field directly
available.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

We never use "sk" so this patch removes it.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Create per-cpu workqueue threads instead of a single
krdsd thread. This is a step towards better scalability.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

set_page_dirty() unconditionally re-enables interrupts, so
if we call it with irqs off, they will be on after the call,
and that's bad. This patch moves the call after we've re-enabled
interrupts in send_drop_to(), so it's safe.

Also, add BUG_ONs to let us know if we ever do call set_page_dirty
with interrupts off.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the RDMA op has aborted with a remote access error,
in addition to what we already do (tell userspace it has
completed with an error) also unmap it and put() the rm.

Otherwise, hangs may occur on arches that track maps and
will not exit without proper cleanup.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rds_poll_waitq's listeners will be awoken if we receive a congestion
notification. Bad performance may result because *all* polled sockets
contend for this single lock. However, it should not be necessary to
wake pollers when a congestion update arrives if they have never
experienced congestion, and not putting these on the waitq will
hopefully greatly reduce contention.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It seems rds_send_drop_to() called
__rds_rdma_send_complete(rs, rm, RDS_RDMA_CANCELED)
with only rds_sock lock, but not rds_message lock. It raced with
other threads that is attempting to modify the rds_message as well,
such as from within rds_rdma_send_complete().
Signed-off-by: NTina Yang <tina.yang@oracle.com>
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RDS's error messages when a connection goes down are a little
extreme. A connection may go down, and it will be re-established,
and everything is fine. This patch links these messages through
rdsdebug(), instead of to printk directly.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

if a machine is shut down without closing sockets properly, and
freeing all MRs, then a BUG_ON will bring it down. This patch
changes these to WARN_ONs -- leaking MRs is not fatal (although
not ideal, and there is more work to do here for a proper fix.)
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix a deadlock between rds_rdma_send_complete() and
rds_send_remove_from_sock() when rds socket lock and
rds message lock are acquired out-of-order.
Signed-off-by: NTina Yang <Tina.Yang@oracle.com>
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have two kinds of loopback: software (via loop transport)
and hardware (via IB). sw is used for 127.0.0.1, and doesn't
support rdma ops. hw is used for sends to local device IPs,
and supports rdma. Both are used in different cases.

For both of these, when there is a congestion map update, we
want to call rds_cong_map_updated() but not actually send
anything -- since loopback local and foreign congestion maps
point to the same spot, they're already in sync.

The old code never called sw loop's xmit_cong_map(),so
rds_cong_map_updated() wasn't being called for it. sw loop
ports would not work right with the congestion monitor.

Fixing that meant that hw loopback now would send congestion maps
to itself. This is also undesirable (racy), so we check for this
case in the ib-specific xmit code.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of waking the send thread whenever any send space is available,
wait until it is at least half empty. This is modeled on how
sock_def_write_space() does it, and may help to minimize context
switches.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Other transports use rds_page_copy_user, which updates our
s_copy_to_user counter. TCP doesn't, so it needs to explicity
call rds_stats_add().
Reported-by: NRichard Frank <richard.frank@oracle.com>
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Most likely cut n paste error - sendmsg() was checking sock_rcvtimeo.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

BUGging on a runtime error code should be avoided. This
patch also eliminates all other BUG()s that have no real
reason to exist.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Andy Grover <andy.grover@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Not including net/atm/

Compiled tested x86 allyesconfig only
Added a > 80 column line or two, which I ignored.
Existing checkpatch plaints willfully, cheerfully ignored.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The RDMA CM is intended to support the use of a loopback address
when establishing a connection; however, the behavior of the CM
when loopback addresses are used is confusing and does not always
work, depending on whether loopback was specified by the server,
the client, or both.

The defined behavior of rdma_bind_addr is to associate an RDMA
device with an rdma_cm_id, as long as the user specified a non-
zero address.  (ie they weren't just trying to reserve a port)
Currently, if the loopback address is passed to rdam_bind_addr,
no device is associated with the rdma_cm_id.  Fix this.

If a loopback address is specified by the client as the destination
address for a connection, it will fail to establish a connection.
This is true even if the server is listing across all addresses or
on the loopback address itself.  The issue is that the server tries
to translate the IP address carried in the REQ message to a local
net_device address, which fails.  The translation is not needed in
this case, since the REQ carries the actual HW address that should
be used.

Finally, cleanup loopback support to be more transport neutral.
Replace separate calls to get/set the sgid and dgid from the
device address to a single call that behaves correctly depending
on the format of the device address.  And support both IPv4 and
IPv6 address formats.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>

[ Fixed RDS build by s/ib_addr_get/rdma_addr_get/  - Roland ]
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

For consistency drop & in front of every proc_handler.  Explicity
taking the address is unnecessary and it prevents optimizations
like stubbing the proc_handlers to NULL.

Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

Now that sys_sysctl is a compatiblity wrapper around /proc/sys
all sysctl strategy routines, and all ctl_name and strategy
entries in the sysctl tables are unused, and can be
revmoed.

In addition neigh_sysctl_register has been modified to no longer
take a strategy argument and it's callers have been modified not
to pass one.

Cc: "David Miller" <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: netdev@vger.kernel.org
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

The generic __sock_create function has a kern argument which allows the
security system to make decisions based on if a socket is being created by
the kernel or by userspace.  This patch passes that flag to the
net_proto_family specific create function, so it can do the same thing.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move receive processing from event handler to a tasklet.
This should help prevent hangcheck timer from going off
when RDS is under heavy load.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This issue was discovered by HP's Pradeep and fixed in OFED
1.3, but not fixed in later versions, since the fix's implementation
was not immediately applyable to the later code. This patch should
do the trick for 1.4+ codebases.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove explicit destruction of passive connection when destroying
active end of the connection. The passive end is also on the
device's connection list, and will thus be cleaned up properly.
Panic was caused by trying to clean it up twice.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

"At rds_ib_recv_refill_one(), it first executes atomic_read(&rds_ib_allocation)
for if-condition checking,

and then executes atomic_inc(&rds_ib_allocation) if the condition was
not satisfied.

However, if any other code which updates rds_ib_allocation executes
between these two atomic operation executions,
it seems that it may result race condition. (especially when
rds_ib_allocation + 1 == rds_ib_sysctl_max_recv_allocation)"

This patch fixes this by using atomic_inc_unless to eliminate the
possibility of allocating more than rds_ib_sysctl_max_recv_allocation
and then decrementing the count if the allocation fails. It also
makes an identical change to the iwarp transport.
Reported-by: NShin Hong <hongshin@gmail.com>
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RDS currently supports a GET_MR sockopt to establish a
memory region (MR) for a chunk of memory. However, the fastreg
method ties a MR to a particular destination. The GET_MR_FOR_DEST
sockopt allows the remote machine to be specified, and thus
support for fastreg (aka FRWRs).

Note that this patch does *not* do all of this - it simply
implements the new sockopt in terms of the old one, so applications
can begin to use the new sockopt in preparation for cutover to
FRWRs.
Signed-off-by: NAndy Grover <andy.grover@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>