In the current implementation, the driver tries to allocate contiguous
memory, and if it fails, it falls back to 4K fragmented allocation.

Once the memory is fragmented, the first allocation might take a lot
of time, and even fail, which can cause connection failures.

This patch changes the logic to always allocate with 4K granularity,
since it's more robust and more likely to succeed.

This patch was tested with Lustre and no performance degradation
was observed.

Note: This commit eliminates the "shrinking WQE" feature. This feature
depended on using vmap to create a virtually contiguous send WQ.
vmap use was abandoned due to problems with several processors (see the
commit cited below). As a result, shrinking WQE was available only with
physically contiguous send WQs. Allocating such send WQs caused the
problems described above.
Therefore, as a side effect of eliminating the use of large physically
contiguous send WQs, the shrinking WQE feature became unavailable.

Warning example:
worker/20:1: page allocation failure: order:8, mode:0x80d0
CPU: 20 PID: 513 Comm: kworker/20:1 Tainted: G OE ------------
Workqueue: ib_cm cm_work_handler [ib_cm]
Call Trace:
[<ffffffff81686d81>] dump_stack+0x19/0x1b
[<ffffffff81186160>] warn_alloc_failed+0x110/0x180
[<ffffffff8118a954>] __alloc_pages_nodemask+0x9b4/0xba0
[<ffffffff811ce868>] alloc_pages_current+0x98/0x110
[<ffffffff81184fae>] __get_free_pages+0xe/0x50
[<ffffffff8133f6fe>] swiotlb_alloc_coherent+0x5e/0x150
[<ffffffff81062551>] x86_swiotlb_alloc_coherent+0x41/0x50
[<ffffffffa056b4c4>] mlx4_buf_direct_alloc.isra.7+0xc4/0x180 [mlx4_core]
[<ffffffffa056b73b>] mlx4_buf_alloc+0x1bb/0x260 [mlx4_core]
[<ffffffffa0b15496>] create_qp_common+0x536/0x1000 [mlx4_ib]
[<ffffffff811c6ef7>] ? dma_pool_free+0xa7/0xd0
[<ffffffffa0b163c1>] mlx4_ib_create_qp+0x3b1/0xdc0 [mlx4_ib]
[<ffffffffa0b01bc2>] ? mlx4_ib_create_cq+0x2d2/0x430 [mlx4_ib]
[<ffffffffa0b21f20>] mlx4_ib_create_qp_wrp+0x10/0x20 [mlx4_ib]
[<ffffffffa08f152a>] ib_create_qp+0x7a/0x2f0 [ib_core]
[<ffffffffa06205d4>] rdma_create_qp+0x34/0xb0 [rdma_cm]
[<ffffffffa08275c9>] kiblnd_create_conn+0xbf9/0x1950 [ko2iblnd]
[<ffffffffa074077a>] ? cfs_percpt_unlock+0x1a/0xb0 [libcfs]
[<ffffffffa0835519>] kiblnd_passive_connect+0xa99/0x18c0 [ko2iblnd]

Fixes: 73898db0 ("net/mlx4: Avoid wrong virtual mappings")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This clearly indicates that the input is a bitwise combination of values
in an enum, and identifies which enum contains the definition of the bits.

Special accessors are provided that handle the mandatory validation of the
allowed bits and enforce the correct type for bitwise flags.

If we had introduced this at the start then the kabi would have uniformly
used u64 data to pass flags, however today there is a mixture of u64 and
u32 flags. All places are converted to accept both sizes and the accessor
fixes it. This allows all existing flags to grow to u64 in future without
any hassle.

Finally all flags are, by definition, optional. If flags are not passed
the accessor does not fail, but provides a value of zero.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>

Since neither ib_post_send() nor ib_post_recv() modify the data structure
their second argument points at, declare that argument const. This change
makes it necessary to declare the 'bad_wr' argument const too and also to
modify all ULPs that call ib_post_send(), ib_post_recv() or
ib_post_srq_recv(). This patch does not change any functionality but makes
it possible for the compiler to verify whether the
ib_post_(send|recv|srq_recv) really do not modify the posted work request.

To make this possible, only one cast had to be introduce that casts away
constness, namely in rpcrdma_post_recvs(). The only way I can think of to
avoid that cast is to introduce an additional loop in that function or to
change the data type of bad_wr from struct ib_recv_wr ** into int
(an index that refers to an element in the work request list). However,
both approaches would require even more extensive changes than this
patch.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Since the next patch will constify the wr pointer, do not modify the data
that pointer points at.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

When posting a send work request, the work request that is posted is not
modified by any of the RDMA drivers. Make this explicit by constifying
most ib_send_wr pointers in RDMA transport drivers.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Since the next patch will change the return type of these functions into a
const pointer and since the iSER driver modifies the work request these
functions return a pointer two, inline two work request conversion
function calls. This patch does not change any functionality.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Code changes in smc have become so complicated this cycle that the RDMA
patches to remove ib_query_gid in smc create too complex merge conflicts.
Allow those conflicts to be resolved by using the net/smc hunks by
providing a compatibility wrapper. During the second phase of the merge
window this wrapper will be deleted and smc updated to use the new API.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The driver implements the modify_cq callback, but did not set the bit to
expose it to userspace.
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Because the data structure of hip08 is little endian, it needs to fix the
immediate field of wqe and cqe into __le32.
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

In order to avoid using usleep function in lock function, we use delay
function instead of it.  Besides, it also use brackets for standardized
the computed order.
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

When hop_num is more than three, it need to return -EINVAL.  This patch
fixes it.
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

When create loop qp fail, it will return the correct result when
modify_qp() fails.
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This patch adds PCI matching for the hns 50GE NIC.
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

When init cmq fail in initial flow of RoCE, it should return the errno of
cmq_init function, not of the rest call.
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

When a CX5 device is configured in dual-port RoCE mode, after creating
many VFs against port 1, creating the same number of VFs against port 2
will flood kernel/syslog with something like
"mlx5_*:mlx5_ib_bind_slave_port:4266:(pid 5269): port 2 already
affiliated."

So basically, when traversing mlx5_ib_dev_list, mlx5_ib_add_slave_port()
repeatedly attempts to bind the new mpi structure to every device on the
list until it finds an unbound device.

Change the log level from warn to dbg to avoid log flooding as the warning
should be harmless.
Signed-off-by: Qing Huang <qing.huang@oracle.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This patch avoids that the following compiler warning is reported when
building with gcc 8 and W=1:

drivers/infiniband/hw/usnic/usnic_fwd.c:95:2: warning: 'strncpy' output may be truncated copying 16 bytes from a string of length 20 [-Wstringop-truncation]
  strncpy(ufdev->name, netdev_name(ufdev->netdev),
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    sizeof(ufdev->name) - 1);
    ~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The call in svc_rdma_post_chunk_ctxt() does actually use bad_wr.

Fixes: ed288d74 ("net/xprtrdma: Simplify ib_post_(send|recv|srq_recv)() calls")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Currently if the cm_id is not bound to any netdevice, than for such cm_id,
net namespace is ignored; which is incorrect.

Regardless of cm_id bound to a netdevice or not, net namespace must
match. When a cm_id is bound to a netdevice, in such case net namespace
and netdevice both must match.

Fixes: 4c21b5bc ("IB/cma: Add net_dev and private data checks to RDMA CM")
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

When netdevice is not found for a request, and if it for RoCE port,
currently it allows matching the listener as long as port number matches
by ignoring the netdevice.

Now that we always prefer to have netdevice associated with RoCE, when
netdevice is not found, don't consider RoCE ports.

In other words, a NULL netdevice with RoCE is not acceptable. Therefore,
remove this confusing RoCE port ignorance check.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

For RoCE, when CM requests are received for RC and UD connections,
netdevice of the incoming request is unavailable. Because of that CM
requests are always forwarded to init_net namespace.

Now that we have the GID attribute available, introduce SGID attribute in
incoming CM requests and refer to the netdevice of it.  This is similar to
existing SGID attribute field in outgoing CM requests for RC and UD
transports.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This driver doesn't provide any kernel services, it only provides
an interface via uverbs, so it should depend on, not select, uverbs
support.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This patch implements the srq specific verbs such as create/destroy/modify
and post_srq_recv. And adds srq specific structures and defines to t4.h
and uapi.

Also updates the cq poll logic to deal with completions that are
associated with the SRQ's.

This patch also handles kernel mode SRQ_LIMIT events as well as flushed
SRQ buffers
Signed-off-by: Raju Rangoju <rajur@chelsio.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This patch adds kernel mode t4_srq structures and support functions,
uapi structures and defines, as well as firmware work request structures.
Signed-off-by: Raju Rangoju <rajur@chelsio.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Remove unnecessary parentheses to fix the clang warning of extraneous
parentheses.
Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This patch avoids that the following compiler warning is reported when
building with gcc 8 and W=1:

In function 'ocrdma_mbx_get_ctrl_attribs',
    inlined from 'ocrdma_init_hw' at drivers/infiniband/hw/ocrdma/ocrdma_hw.c:3224:11:
drivers/infiniband/hw/ocrdma/ocrdma_hw.c:1368:3: warning: 'strncpy' output may be truncated copying 31 bytes from a string of length 31 [-Wstringop-truncation]
   strncpy(dev->model_number,
   ^~~~~~~~~~~~~~~~~~~~~~~~~~
    hba_attribs->controller_model_number, 31);
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

We have a parallel unlocked reader and writer with ib_uverbs_get_context()
vs everything else, and nothing guarantees this works properly.

Audit and fix all of the places that access ucontext to use one of the
following locking schemes:
- Call ib_uverbs_get_ucontext() under SRCU and check for failure
- Access the ucontext through an struct ib_uobject context member
  while holding a READ or WRITE lock on the uobject.
  This value cannot be NULL and has no race.
- Hold the ucontext_lock and check for ufile->ucontext !NULL

This also re-implements ib_uverbs_get_ucontext() in a way that is safe
against concurrent ib_uverbs_get_context() and disassociation.

As a side effect, every access to ucontext in the commands is via
ib_uverbs_get_context() with an error check, or via the uobject, so there
is no longer any need for the core code to check ucontext on every command
call. These checks are also removed.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This approach matches the standard flow of the typical write method that
relies on the HW object to store the device and the uobject to access the
ucontext.  Avoids the use of the devx_ufile2uctx in several places will
make revising the semantics of ib_uverbs_get_ucontext() in the next patch
simpler.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Allocating the struct file during alloc_begin creates this strange
asymmetry with IDR, where the FD has two krefs pointing at it during the
pre-commit phase. In particular this makes the abort process for FD very
strange and confusing.

For instance abort currently calls the type's destroy_object twice, and
the fops release once if abort is done. This is very counter intuitive. No
fops should be called until alloc_commit succeeds, and destroy_object
should only ever be called once.

Moving the struct file allocation to the alloc_commit is now simple, as we
already support failure of rdma_alloc_commit_uobject, with all the
required rollback pieces.

This creates an understandable symmetry with IDR and simplifies/fixes the
abort handling for FD types.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The ioctl framework already does this correctly, but the write path did
not. This is trivially fixed by simply using a standard pattern to return
uobj_alloc_commit() as the last statement in every function.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The locking here has always been a bit crazy and spread out, upon some
careful analysis we can simplify things.

Create a single function uverbs_destroy_ufile_hw() that internally handles
all locking. This pulls together pieces of this process that were
sprinkled all over the places into one place, and covers them with one
lock.

This eliminates several duplicate/confusing locks and makes the control
flow in ib_uverbs_close() and ib_uverbs_free_hw_resources() extremely
simple.

Unfortunately we have to keep an extra mutex, ucontext_lock.  This lock is
logically part of the rwsem and provides the 'down write, fail if write
locked, wait if read locked' semantic we require.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Rename 'cleanup_rwsem' to 'hw_destroy_rwsem' which is held across any call
to the type destroy function (aka 'hw' destroy). The main purpose of this
lock is to prevent normal add and destroy from running concurrently with
uverbs_cleanup_ufile()

Since the uobjects list is always manipulated under the 'hw_destroy_rwsem'
we can eliminate the uobjects_lock in the cleanup function. This allows
converting that lock to a very simple spinlock with a narrow critical
section.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The locking requirements here have changed slightly now that we can rely
on the ib_uverbs_file always existing and containing all the necessary
locking infrastructure.

That means we can get rid of the cleanup_mutex usage (this was protecting
the check on !uboj->context).

Otherwise, follow the same pattern that IDR uses for destroy, acquire
exclusive write access, then call destroy and the undo the 'lookup'.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This wasn't wrong, but the placement of two krefs didn't make any
sense. Follow some simple rules.

- A kref is held inside uobjects_list
- A kref is held inside the IDR
- A kref is held inside file->private
- A stack based kref is passed bettwen alloc_begin and
  alloc_abort/alloc_commit

Any place we destroy one of the above pointers, we stick a put,
or 'move' the kref into another pointer.

The key functions have sensible semantics:
- alloc_uobj fully initializes the common members in uobj, including
  the list
- Get rid of the uverbs_idr_remove_uobj helper since IDR remove
  does require put, but it depends on the situation. Later
  patches will re-consolidate this differently.
- alloc_abort always consumes the passed kref, done in the type
- alloc_commit always consumes the passed kref, done in the type
- rdma_remove_commit_uobject always pairs with a lookup_get

After it is all done the only control flow change is to:
- move a get from alloc_commit_fd_uobject to rdma_alloc_commit_uobject
- add a put to remove_commit_idr_uobject
- Consistenly use rdma_lookup_put in rdma_remove_commit_uobject at
  the right place
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The alloc_commit callback makes the uobj visible to other threads,
and it does so using a 'move' semantic of the uobj kref on the stack
into the public storage (eg the IDR, uobject list and file_private_data)

Once this is done another thread could start up and trigger deletion
of the kref. Fortunately cleanup_rwsem happens to prevent this from
being a bug, but that is a fantastically unclear side effect.

Re-organize things so that alloc_commit is that last thing to touch
the uobj, get rid of the sneaky implicit dependency on cleanup_rwsem,
and add a comment reminding that uobj is no longer kref'd after
alloc_commit.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Our ABI for write() uses a s32 for FDs and a u32 for IDRs, but internally
we ended up implicitly casting these ABI values into an 'int'. For ioctl()
we use a s64 for FDs and a u64 for IDRs, again casting to an int.

The various casts to int are all missing range checks which can cause
userspace values that should be considered invalid to be accepted.

Fix this by making the generic lookup routine accept a s64, which does not
truncate the write API's u32/s32 or the ioctl API's s64. Then push the
detailed range checking down to the actual type implementations to be
shared by both interfaces.

Finally, change the copy of the uobj->id to sign extend into a s64, so eg,
if we ever wish to return a negative value for a FD it is carried
properly.

This ensures that userspace values are never weirdly interpreted due to
the various trunctations and everything that is really out of range gets
an EINVAL.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

If the method fails after calling rdma_explicit_destroy (eg if
copy_to_user faults) then it will trigger a kernel oops:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
PGD 800000000548d067 P4D 800000000548d067 PUD 54a0067 PMD 0
SMP PTI
CPU: 0 PID: 359 Comm: ibv_rc_pingpong Not tainted 4.18.0-rc1+ #28
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
RIP: 0010:          (null)
Code: Bad RIP value.
RSP: 0018:ffffc900001a3bf0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88000603bd00 RCX: 0000000000000003
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff88000603bd00
RBP: 0000000000000001 R08: ffffc900001a3cf8 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc900001a3cf0
R13: 0000000000000000 R14: ffffc900001a3cf0 R15: 0000000000000000
FS:  00007fb00dda8700(0000) GS:ffff880007c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 000000000548e004 CR4: 00000000003606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ? rdma_lookup_put_uobject+0x22/0x50 [ib_uverbs]
 ? uverbs_finalize_object+0x3b/0x60 [ib_uverbs]
 ? uverbs_finalize_attrs+0x128/0x140 [ib_uverbs]
 ? ib_uverbs_cmd_verbs+0x698/0x7c0 [ib_uverbs]
 ? find_held_lock+0x2d/0x90
 ? __might_fault+0x39/0x90
 ? ib_uverbs_ioctl+0x111/0x1f0 [ib_uverbs]
 ? do_vfs_ioctl+0xa0/0x6d0
 ? trace_hardirqs_on_caller+0xed/0x180
 ? _raw_spin_unlock_irq+0x24/0x40
 ? syscall_trace_enter+0x138/0x1d0
 ? ksys_ioctl+0x35/0x60
 ? __x64_sys_ioctl+0x11/0x20
 ? do_syscall_64+0x5b/0x1c0
 ? entry_SYSCALL_64_after_hwframe+0x49/0xbe

This is because the type was replaced with the null_type during explicit
destroy that cannot complete the destruction.

One of the side effects of replacing the type is to make the object
handle totally unreachable - so no other command could attempt to use
it, even though it remains on the uboject list.

We can get the same end result by just fully destroying the object inside
rdma_explicit_destroy and leaving the caller the residual kref for the
uobj with no attached HW object, and no presence in the ubojects list.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>

Instead of declaring and passing a dummy 'bad_wr' pointer, pass NULL
as third argument to ib_post_(send|recv|srq_recv)().
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Instead of declaring and passing a dummy 'bad_wr' pointer, pass NULL
as third argument to ib_post_(send|recv|srq_recv)().
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Remove a WARN_ON() statement that verifies something that is guaranteed
by the RDMA API, namely that the failed_wr pointer is not touched if an
ib_post_send() call succeeds and that it points at the failed wr if an
ib_post_send() call fails.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Instead of declaring and passing a dummy 'bad_wr' pointer, pass NULL
as third argument to ib_post_(send|recv|srq_recv)().
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>