The specs are required to operate the uverbs file, so they belong inside
the ib_uverbs_device, not inside the ib_device. The spec passed in the
ib_device is just a communication from the driver and should not be used
during runtime.

This also changes the lifetime of the spec memory to match the
ib_uverbs_device, however at this time the spec_root can still contain
driver pointers after disassociation, so it cannot be used if ib_dev is
NULL. This is preparation for another series.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Reviewed-by: NMichael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

For dependencies, branch based on 'mellanox/mlx5-next' of
git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux.git

Pull Dump and fill MKEY from Leon Romanovsky:

====================
MLX5 IB HCA offers the memory key, dump_fill_mkey to increase performance,
when used in a send or receive operations.

It is used to force local HCA operations to skip the PCI bus access, while
keeping track of the processed length in the ibv_sge handling.

In this three patch series, we expose various bits in our HW spec
file (mlx5_ifc.h), move unneeded for mlx5_core FW command and export such
memory key to user space thought our mlx5-abi header file.
====================

Botched auto-merge in mlx5_ib_alloc_ucontext() resolved by hand.

* branch 'mlx5-dump-fill-mkey':
  IB/mlx5: Expose dump and fill memory key
  net/mlx5: Add hardware definitions for dump_fill_mkey
  net/mlx5: Limit scope of dump_fill_mkey function
  net/mlx5: Rate limit errors in command interface
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

MLX5 IB HCA offers the memory key, dump_fill_mkey to boost
performance, when used in a send or receive operations.

It is used to force local HCA operations to skip the PCI bus access,
while keeping track of the processed length in the ibv_sge handling.

Meaning, instead of a PCI write access the HCA leaves the target
memory untouched, and skips filling that packet section. Similar
behavior is done upon send, the HCA skips data in memory relevant
to this key and saves PCI bus access.

This functionality saves PCI read/write operations.
Signed-off-by: NYonatan Cohen <yonatanc@mellanox.com>
Reviewed-by: NYishai Hadas <yishaih@mellanox.com>
Reviewed-by: NGuy Levi <guyle@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

MLX5 IB HCA offers the memory key, dump_fill_mkey to boost
performance by forcing local HCA operations to skip the PCI bus
access,

This patch adds needed hardware definitions.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

mlx5_core_dump_fill_mkey() is going to be used in next
patch in IB and doesn't need to be visible to whole
mlx5_core. Move that command to mlx5_ib.
Signed-off-by: NYonatan Cohen <yonatanc@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

The srq->swq[] is allocated in bnxt_qplib_create_srq().  It has
srq->hwq.max_elements elements so these tests should be > instead of >=
or we might go beyond the end of the array.

Fixes: 1ac5a404 ("RDMA/bnxt_re: Add bnxt_re RoCE driver")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NSelvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The sgid_tbl->tbl[] array is allocated in bnxt_qplib_alloc_sgid_tbl().
It has sgid_tbl->max elements.  So the > should be >= to prevent
accessing one element beyond the end of the array.

Fixes: 1ac5a404 ("RDMA/bnxt_re: Add bnxt_re RoCE driver")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NSelvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

"nents" is an unsigned int, so if ib_map_mr_sg() returns a negative
error code then it's type promoted to a high unsigned int which is
treated as success.

Fixes: a060b562 ("IB/core: generic RDMA READ/WRITE API")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The 2.6.18... was a hell of a ride, and by now both me and
Roi are not dealing with iser any more. Max will replace us
as maintainer, good luck to you dear!
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Acked-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

VMA lookup is supposed to be performed while mmap_sem is held.

Fixes: f26c7c83 ("i40iw: Add 2MB page support")
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

rdma_ah_find_type() can reach into ib_device->port_immutable with a
potentially out-of-bounds port number, so check that the port number is
valid first.

Fixes: 44c58487 ("IB/core: Define 'ib' and 'roce' rdma_ah_attr types")
Signed-off-by: NTarick Bedeir <tarick@google.com>
Reviewed-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

On repeated module load/unload cycles, its possible for the pvrmda driver
to encounter this crash:

...
[  297.032448] RIP: 0010:[<ffffffff839e4620>]  [<ffffffff839e4620>] netdev_walk_all_upper_dev_rcu+0x50/0xb0
[  297.034078] RSP: 0018:ffff95087780bd08  EFLAGS: 00010286
[  297.034986] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff95087a0c0000
[  297.036196] RDX: ffff95087a0c0000 RSI: ffffffff839e44e0 RDI: ffff950835d0c000
[  297.037421] RBP: ffff95087780bd40 R08: ffff95087a0e0ea0 R09: abddacd03f8e0ea0
[  297.038636] R10: abddacd03f8e0ea0 R11: ffffef5901e9dbc0 R12: ffff95087a0c0000
[  297.039854] R13: ffffffff839e44e0 R14: ffff95087a0c0000 R15: ffff950835d0c828
[  297.041071] FS:  0000000000000000(0000) GS:ffff95087fc00000(0000) knlGS:0000000000000000
[  297.042443] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  297.043429] CR2: ffffffffffffffe8 CR3: 000000007a652000 CR4: 00000000003607f0
[  297.044674] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  297.045893] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  297.047109] Call Trace:
[  297.047545]  [<ffffffff839e4698>] netdev_has_upper_dev_all_rcu+0x18/0x20
[  297.048691]  [<ffffffffc05d31af>] is_eth_port_of_netdev+0x2f/0xa0 [ib_core]
[  297.049886]  [<ffffffffc05d3180>] ? is_eth_active_slave_of_bonding_rcu+0x70/0x70 [ib_core]
...

This occurs because vmw_pvrdma on probe stores a pointer to the netdev
that exists on function 0 of the same bus/device/slot (which represents
the vmxnet3 ethernet driver).  However, it never removes this pointer if
the vmxnet3 module is removed, leading to crashes resulting from use after
free dereferencing incidents like the one above.

The fix is pretty straightforward.  vmw_pvrdma should listen for
NETDEV_REGISTER and NETDEV_UNREGISTER events in its event listener code
block, and update the stored netdev pointer accordingly.  This solution
has been tested by myself and the reporter with successful results.  This
fix also allows the pvrdma driver to find its underlying ethernet device
in the event that vmxnet3 is loaded after pvrdma, which it was not able to
do before.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Reported-by: ruquin@redhat.com
Tested-by: NAdit Ranadive <aditr@vmware.com>
Acked-by: NAdit Ranadive <aditr@vmware.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Currently the driver sets the mask of the gre_protocol to 0xffff
without consideration in the user request.

Fix it by copy the mask from the verbs spec.

Fixes: da2f22ae ("IB/mlx5: Add support for GRE flow specification")
Signed-off-by: NMaor Gottlieb <maorg@mellanox.com>
Reviewed-by: NAriel Levkovich <lariel@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The general interrupt handler is_rcv_avail_int() has two paths,
do_interrupt() (callback) and handle_user_interrupt().  The
do_interrupt() callback is for the threaded receive handling.
is_rcv_avail_int() cannot handle threaded IRQs.

If the do_interrupt() path is taken, and the IRQ returns
IRQ_WAKE_THREAD, the IRQ behavior will be indeterminate.

Remove incorrect call to do_interrupt() from is_rcv_avail_int(),
leaving the un-threaded (handle_user_interrupt()) path.

Fixes: f4f30031 ("staging/rdma/hfi1: Thread the receive interrupt.")
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NKamenee Arumugam <kamenee.arumugam@intel.com>
Signed-off-by: NMichael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The in_use_ctxts bitmask is for user receive contexts only.  Setting it for
any other type of receive context is incorrect.

Move initial set of in_use_ctxts bits from the general context init to the
user context specific init. Having this bit set can allow contexts to be
incorrectly identified by some IRQ handlers. This will allow
handle_user_interrupt() will now filter user contexts correctly.

Clean up redundant is_rcv_urgent_int() user context check.

A follow on patch will clean up an incorrect code path in the
is_rcv_avail_int().

Fixes: 8737ce95 ("IB/hfi1: Fix an assign/ordering issue with shared context IDs")
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NKamenee Arumugam <kamenee.arumugam@intel.com>
Signed-off-by: NMichael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

BUG: KASAN: use-after-free in srpt_set_enabled+0x1a9/0x1e0 [ib_srpt]
Read of size 4 at addr ffff8801269d23f8 by task check/29726

CPU: 4 PID: 29726 Comm: check Not tainted 4.18.0-rc2-dbg+ #4
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Call Trace:
 dump_stack+0xa4/0xf5
 print_address_description+0x6f/0x270
 kasan_report+0x241/0x360
 __asan_load4+0x78/0x80
 srpt_set_enabled+0x1a9/0x1e0 [ib_srpt]
 srpt_tpg_enable_store+0xb8/0x120 [ib_srpt]
 configfs_write_file+0x14e/0x1d0 [configfs]
 __vfs_write+0xd2/0x3b0
 vfs_write+0x101/0x270
 ksys_write+0xab/0x120
 __x64_sys_write+0x43/0x50
 do_syscall_64+0x77/0x230
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f235cfe6154

Fixes: aaf45bd8 ("IB/srpt: Detect session shutdown reliably")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Avoid that KASAN reports the following:

BUG: KASAN: use-after-free in srpt_close_ch+0x4f/0x1b0 [ib_srpt]
Read of size 4 at addr ffff880151180cb8 by task check/4681

CPU: 15 PID: 4681 Comm: check Not tainted 4.18.0-rc2-dbg+ #4
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Call Trace:
 dump_stack+0xa4/0xf5
 print_address_description+0x6f/0x270
 kasan_report+0x241/0x360
 __asan_load4+0x78/0x80
 srpt_close_ch+0x4f/0x1b0 [ib_srpt]
 srpt_set_enabled+0xf7/0x1e0 [ib_srpt]
 srpt_tpg_enable_store+0xb8/0x120 [ib_srpt]
 configfs_write_file+0x14e/0x1d0 [configfs]
 __vfs_write+0xd2/0x3b0
 vfs_write+0x101/0x270
 ksys_write+0xab/0x120
 __x64_sys_write+0x43/0x50
 do_syscall_64+0x77/0x230
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: aaf45bd8 ("IB/srpt: Detect session shutdown reliably")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Avoid that the compiler complains about set-but-not-used variables when
building with W=1. This patch does not change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: Leon Romanovsky <leonro@mellanox.com>
Acked-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Remove the driver version and release date information because such
information is not relevant for an upstream driver. See also commit
e1267b01 ("RDMA: Remove useless MODULE_VERSION").
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

IB_MULTICAST_LID_BASE is defined as follows:

  #define IB_MULTICAST_LID_BASE   cpu_to_be16(0xC000)

Hence use be16_to_cpu() to convert it to CPU endianness. Compile-tested
only.

Fixes: af808ece ("IB/SA: Check dlid before SA agent queries for ClassPortInfo")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: Venkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Improve uverbs_cleanup_ucontext algorithm to work properly when the
topology graph of the objects cannot be determined at compile time.  This
is the case with objects created via the devx interface in mlx5.

Typically uverbs objects must be created in a strict topologically sorted
order, so that LIFO ordering will generally cause them to be freed
properly. There are only a few cases (eg memory windows) where objects can
point to things out of the strict LIFO order.

Instead of using an explicit ordering scheme where the HW destroy is not
allowed to fail, go over the list multiple times and allow the destroy
function to fail. If progress halts then a final, desperate, cleanup is
done before leaking the memory. This indicates a driver bug.
Signed-off-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Since there are adapters that have four ports, increase the size of
the srpt_device.port[] array. This patch avoids that the following
warning is hit with quad port Chelsio adapters:

    WARN_ON(sdev->device->phys_port_cnt > ARRAY_SIZE(sdev->port));
Reported-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: Steve Wise <swise@opengridcomputing.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: <stable@vger.kernel.org>
Reviewed-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

We need to set can_queue earlier than when enabling the scsi host.
in a blk-mq enabled environment, the tagset allocation is taken
from can_queue which cannot be modified later. Also, pass an updated
.can_queue to iscsi_session_setup to have enough iscsi tasks allocated
in the session kfifo.
Reported-by: NKarandeep Chahal <karandeepchahal@gmail.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Do not call sk_dst_set() on every packet transfer because
that calls sk_tx_queue_clear(), which clears the tx queue.
A QP must stay on the same tx queue to maintain packet order.
Signed-off-by: NVijay Immanuel <vijayi@attalasystems.com>
Acked-by: NMoni Shoua <monis@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

This lock used to be protecting a call to dst_get_neighbour_noref,
however the below commit changed it to dst_neigh_lookup which no longer
requires rcu.

Access to nud_state, neigh_event_send or rdma_copy_addr does not require
RCU, so delete the lock.

Fixes: 02b61955 ("infiniband: Convert dst_fetch_ha() over to dst_neigh_lookup().")
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

The failure in releasing one UAR doesn't mean that we can't continue to
release rest of system pages, so don't return too early.

As part of cleanup, there is no need to print warning if
mlx5_cmd_free_uar() fails because such warning will be printed as part of
mlx5_cmd_exec().
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

This function is not in use - delete it.
Signed-off-by: NYuval Shaia <yuval.shaia@oracle.com>
Acked-by: NAdit Ranadive <aditr@vmware.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

port_num is untrusted data from the user, so it should be checked after
calling fill_sgid_attr, which validates it.

Fixes: 8d9ec9ad ("IB/core: Add a sgid_attr pointer to struct rdma_ah_attr")
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Any error status returned by FW will trigger a print similar to the
following error message in the dmesg.

[   55.884355] mlx5_core 0000:00:04.0: mlx5_cmd_check:712:(pid 555):
ALLOC_UAR(0x802) op_mod(0x0) failed, status limits exceeded(0x8),
syndrome (0x0)

Those prints are extremely valuable to diagnose issues with running system
and it is important to keep them. However, not-so-careful user can trigger
endless number of such prints by depleting HW resources and will spam
dmesg.

Rate limiting of such messages solves this issue.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Since slave GID's do not exist in the core gid table we can no longer use
the core code to help do this without creating inconsistencies. Directly
create the AH using mlx4 internal APIs.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Reviewed-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

kern_spec->reserved is checked prior to calling
kern_spec_to_ib_spec_filter() which makes this second check redundant.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

dma_map_sg_attrs() returns 0 on error and can't return a negative number
(ensured by BUG_ON), so don't check.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Number of specs is provided by user and in valid case can be equal to zero.
Such argument causes to call to kcalloc() with zero-length request and in
return the ZERO_SIZE_PTR is assigned. This pointer is different from NULL
and makes various if (..) checks to success.

Fixes: b6ba4a9a ("IB/uverbs: Add support for flow counters")
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Following the removal of ib_create_flow(), adjust the code to get rid of
ib_destroy_flow() too.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

There are no kernel users of this interface so lets drop it.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

In the accepted series "Refactor ib_uverbs_write path", we presented the
roadmap to get rid of uverbs_cmd_mask and uverbs_ex_cmd_mask fields in
favor of simple check of function pointer. So let's put NULL check of
create_flow function callback despite the fact that uverbs_ex_cmd_mask
still exists.

Link: https://www.spinics.net/lists/linux-rdma/msg60753.htmlSuggested-by: NMichael J Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Reflect the acquisition of SanDisk by Western Digital in my e-mail
address. Remove the reference to David Dillow's git tree since SRP patches
are queued by Doug and Jason. Remove the reference to the OpenFabrics
website since the srp_daemon source code has been moved from that website
into the rdma-core project. Add an entry for the SRP target driver.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: David Dillow <dillow@google.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

usnic has a modified version of the core codes' ib_umem_get() and
related, and the copy misses many of the bug fixes done over the years:

Commit bc3e53f6 ("mm: distinguish between mlocked and pinned pages")
Commit 87773dd5 ("IB: ib_umem_release() should decrement mm->pinned_vm
                      from ib_umem_get")
Commit 8494057a ("IB/uverbs: Prevent integer overflow in ib_umem_get
                      address arithmetic")
Commit 8abaae62 ("IB/core: disallow registering 0-sized memory region")
Commit 66578b0b ("IB/core: don't disallow registering region starting
                      at 0x0")
Commit 53376fed ("RDMA/core: not to set page dirty bit if it's already
                      set.")
Commit 8e907ed4 ("IB/umem: Use the correct mm during ib_umem_release")
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

This patch follows the logic from ib_core but considers the internal
device state upon executing the involved commands.

Specifically, Upon internal error state modify QP to an error state can
be assumed to be success as each in-progress WR going to be flushed in
error in any case as expected by that modify command.

In addition,
As the drain should never fail the driver makes sure that post_send/recv
will succeed even if the device is already in an internal error state.
As such once the driver will supply the simulated/SW CQEs the CQE for
the drain WR will be handled as well.

In case of an internal error state the CQE for the drain WR may be
completed as part of the main task that handled the error state or by
the task that issued the drain WR.

As the above depends on scheduling the code takes the relevant locks
and actions to make sure that the completion handler for that WR will
always be called after that the post_send/recv were issued but not in
parallel to the other task that handles the error flow.
Signed-off-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

This patch follows the logic from ib_core but considers the internal
device state upon executing the involved commands.

Specifically,
Upon internal error state modify QP to an error state can be assumed to
be success as each in-progress WR going to be flushed in error in any
case as expected by that modify command.

In addition,
As the drain should never fail the driver makes sure that post_send/recv
will succeed even if the device is already in an internal error state.
As such once the driver will supply the simulated/SW CQEs the CQE for
the drain WR will be handled as well.

In case of an internal error state the CQE for the drain WR may be
completed as part of the main task that handled the error state or by
the task that issued the drain WR.

As the above depends on scheduling the code takes the relevant locks and
actions to make sure that the completion handler for that WR will always
be called after that the post_send/recv were issued but not in parallel
to the other task that handles the error flow.
Signed-off-by: NYishai Hadas <yishaih@mellanox.com>
Reviewed-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>