Add shift_overflow() helper to assist driver authors in ensuring that
shift operations don't cause overflows or other odd conditions.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
[kees: tweaked comments and commit log, dropped unneeded assignment]
Signed-off-by: Kees Cook <keescook@chromium.org>

sgid_attr is uninitialized on the stack, initialize it to NULL.

Fixes: 39839107 ("IB/cm: Replace members of sa_path_rec with 'struct sgid_attr *'")
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Yossi Itigin <yosefe@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Move all the checking for pkey and other validity to the __ipoib_vlan_add
function. This removes the last difference from the control flow
of the __ipoib_vlan_add to make the overall design simpler to
understand.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Erez Shitrit <erezsh@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

This fixes a bug in the netlink path where the vlan_rwsem was not
held around __ipoib_vlan_add causing the child_intfs to be manipulated
unsafely.

In the process this greatly simplifies the vlan_rwsem write side locking
to only cover a single non-sleeping statement.

This also further increases the safety of the removal ordering by holding
the netdev of the parent while the child is active to ensure most bugs
become either an oops on a NULL priv or a deadlock on the netdev refcount.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Switching to priv_destructor and needs_free_netdev created a subtle
ordering problem in ipoib_remove_one.

Now that unregister_netdev frees the netdev and priv we must ensure that
the children are unregistered before trying to unregister the parent,
or child unregister will use after free.

The solution is to unregister the children, then parent, in the same batch
all while holding the rtnl_lock. This closes all the races where a new
child could have been added and ensures proper ordering.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

This mutex was introduced to deal with the deadlock formed by calling
unregister_netdev from within the sysfs callback of a netdev.

Now that we have priv_destructor and needs_free_netdev we can switch
to the more targeted solution of running the unregister from a
work queue. This avoids the deadlock and gets rid of the mutex.

The next patch in the series needs this mutex eliminated to create
atomicity of unregisteration.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Now that the unregister_netdev flow for IPoIB no longer relies on external
code we can now introduce the use of priv_destructor and
needs_free_netdev.

The rdma_netdev flow is switched to use the netdev common priv_destructor
instead of the special free_rdma_netdev and the IPOIB ULP adjusted:
 - priv_destructor needs to switch to point to the ULP's destructor
   which will then call the rdma_ndev's in the right order
 - We need to be careful around the error unwind of register_netdev
   as it sometimes calls priv_destructor on failure
 - ULPs need to use ndo_init/uninit to ensure proper ordering
   of failures around register_netdev

Switching to priv_destructor is a necessary pre-requisite to using
the rtnl new_link mechanism.

The VNIC user for rdma_netdev should also be revised, but that is left for
another patch.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Denis Drozdov <denisd@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Now that we have a proper ndo_uninit, move code that naturally pairs
with the ndo_uninit into ndo_init. This allows the netdev core to natually
handle ordering.

This fixes the situation where register_netdev can fail before calling
ndo_init, in which case it wouldn't call ndo_uninit either.

Also move a bunch of duplicated init code that is shared between child
and parent for clarity. Now the child and parent register functions look
very similar.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Currently uninit is sometimes done twice in error flows, and is sprinkled
a bit all over the place.

Improve the clarity of the design by moving all uninit only into
ndo_uinit.

Some duplication is removed:
 - Sometimes IPOIB_STOP_NEIGH_GC was done before unregister, but
   this duplicates the process in ipoib_neigh_hash_init
 - Flushing priv->wq was sometimes done before unregister,
   but that duplicates what has been done in ndo_uninit

Uniniting the IB event queue must remain before unregister_netdev as it
requires the RTNL lock to be dropped, this is moved to a helper to make
that flow really clear and remove some duplication in error flows.

If register_netdev fails (and ndo_init is NULL) then it almost always
calls ndo_uninit, which lets us remove all the extra code from the error
unwinds. The next patch in the series will close the 'almost always' hole
by pairing a proper ndo_init with ndo_uninit.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

The neigh_reap_task is self restarting, but so long as we call
cancel_delayed_work_sync() it will be guaranteed to not be running and
never start again. Thus we don't need to have the racy
IPOIB_STOP_NEIGH_GC bit, or the confusing mismatch of places sometimes
calling flush_workqueue after the cancel.

This fixes a situation where the GC work could have been left running
in some rare situations.
Signed-off-by: Erez Shitrit <erezsh@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This essentially duplicates the netdev's reg_state, so just use that
directly. The reg_state is updated under the rntl_lock, and all places
using GOING_DOWN already acquire the rtnl_lock so checking is safe.

Since the only place we use GOING_DOWN is for the parent device this
does not fix any bugs, but it is a step to tidy up the unregister flow
so that after later patches the flow is uniform and sane.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

To optimize NVME-oF READ IOPs, use a specialized WQE that combines
the RDMA WRITE and SEND_INV WR chain submitted by the NVME-oF target
driver.

This reduces uP overhead per NVME-oF IO, and results in over 10%
improvement in NVME-oF 4K READ IOPs.
Signed-off-by: Potnuri Bharat Teja <bharat@chelsio.com>
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Adds iw_cxgb4 functionality to support RDMA_WRITE_WITH_IMMEDATE opcode.
Signed-off-by: Potnuri Bharat Teja <bharat@chelsio.com>
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

In c4iw_create_qp() there are several struct members which potentially
aren't inintialized like uresp.rq_key.  I've fixed this code before in
in commit ae1fe07f ("RDMA/cxgb4: Fix stack info leak in
c4iw_create_qp()") so this time I'm just going to take a big hammer
approach and memset the whole struct to zero.  Hopefully, it will stay
fixed this time.

In c4iw_create_srq() we don't clear uresp.reserved.

Fixes: 6a0b6174 ("rdma/cxgb4: Add support for kernel mode SRQ's")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

According to IB protocol, there are some cases that work requests must
return the flush error completion status through the completion queue. Due
to hardware limitation, the driver needs to assist the flush process.

This patch adds the support of flush cqe for hip08 in the cases that
needed, such as poll cqe, post send, post recv and aeqe handle.

The patch also considered the compatibility between kernel and user space.
Signed-off-by: Yixian Liu <liuyixian@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The change of ipoib_ah data structure with adding "valid" flag and
checks of ah->valid in ipoib_start_xmit affected multicast packet flow.

Since the multicast flow doesn't invoke path_rec_start, "ah->valid" flag
remains unset, so that ipoib_start_xmit end up with neigh_refresh_path
instead of sending the packet using neigh.

"ah->valid" has to be set in multicast send flow. As a result IPoIB
starts sending packets via neigh immediately and eliminates 60sec delay
of neigh keep alive interval.

The typical example of this issue are two sequential arpings:

arping 11.134.208.9 -> got response (mcast_send)
arping 11.134.208.9 -> no response  (ah->valid = 0)

Fixes: fa9391db ("RDMA/ipoib: Update paths on CLIENT_REREG/SM_CHANGE events")
Signed-off-by: Denis Drozdov <denisd@mellanox.com>
Reviewed-by: Erez Shitrit <erezsh@mellanox.com>
Reviewed-by: Feras Daoud <ferasda@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The disassociate function was broken by design because it failed all
commands. This prevents userspace from calling destroy on a uobject after
it has detected a device fatal error and thus reclaiming the resources in
userspace is prevented.

This fix is now straightforward, when anything destroys a uobject that is
not the user the object remains on the IDR with a NULL context and object
pointer. All lookup locking modes other than DESTROY will fail. When the
user ultimately calls the destroy function it is simply dropped from the
IDR while any related information is returned.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Now that all the callbacks are safe to run concurrently with
disassociation this test can be eliminated. The ufile core infrastructure
becomes entirely self contained and is not sensitive to disassociation.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This does the same as the patch before, except for ioctl. The rules are
the same, but for the ioctl methods the core code handles setting up the
uobject.

- Retrieve the ib_dev from the uobject->context->device. This is
  safe under ioctl as the core has already done rdma_alloc_begin_uobject
  and so CREATE calls are entirely protected by the rwsem.
- Retrieve the ib_dev from uobject->object
- Call ib_uverbs_get_ucontext()
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This is a step to get rid of the global check for disassociation. In this
model, the ib_dev is not proven to be valid by the core code and cannot be
provided to the method. Instead, every method decides if it is able to
run after disassociation and obtains the ib_dev using one of three
different approaches:

- Call srcu_dereference on the udevice's ib_dev. As before, this means
  the method cannot be called after disassociation begins.
  (eg alloc ucontext)
- Retrieve the ib_dev from the ucontext, via ib_uverbs_get_ucontext()
- Retrieve the ib_dev from the uobject->object after checking
  under SRCU if disassociation has started (eg uobj_get)

Largely, the code is all ready for this, the main work is to provide a
ib_dev after calling uobj_alloc(). The few other places simply use
ib_uverbs_get_ucontext() to get the ib_dev.

This flexibility will let the next patches allow destroy to operate
after disassociation.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Commands that are reading/writing to objects can test for an ongoing
disassociation during their initial call to rdma_lookup_get_uobject.  This
directly prevents all of these commands from conflicting with an ongoing
disassociation.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

After all the recent structural changes this is now straightforward, hold
the hw_destroy_rwsem across the entire uobject creation. We already take
this semaphore on the success path, so holding it a bit longer is not
going to change the performance.

After this change none of the create callbacks require the
disassociate_srcu lock to be correct.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

After all the recent structural changes this is now straightfoward, hoist
the hw_destroy_rwsem up out of rdma_destroy_explicit and wrap it around
the uobject write lock as well as the destroy.

This is necessary as obtaining a write lock concurrently with
uverbs_destroy_ufile_hw() will cause malfunction.

After this change none of the destroy callbacks require the
disassociate_srcu lock to be correct.

This requires introducing a new lookup mode, UVERBS_LOOKUP_DESTROY as the
IOCTL interface needs to hold an unlocked kref until all command
verification is completed.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This is more readable, and future patches will need a 3rd lookup type.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

There are several flows that can destroy a uobject and each one is
minimized and sprinkled throughout the code base, making it difficult to
understand and very hard to modify the destroy path.

Consolidate all of these into uverbs_destroy_uobject() and call it in all
cases where a uobject has to be destroyed.

This makes one change to the lifecycle, during any abort (eg when
alloc_commit is not called) we always call out to alloc_abort, even if
remove_commit needs to be called to delete a HW object.

This also renames RDMA_REMOVE_DURING_CLEANUP to RDMA_REMOVE_ABORT to
clarify its actual usage and revises some of the comments to reflect what
the life cycle is for the type implementation.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The ridiculous dance with uobj_remove_commit() is not needed, the write
path can follow the same flow as ioctl - lock and destroy the HW object
then use the data left over in the uobject to form the response to
userspace.

Two helpers are introduced to make this flow straightforward for the
caller.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The core code will destroy the HW object on behalf of the method, if the
method provides an implementation it must simply copy data from the stub
uobj into the response. Destroy methods cannot touch the HW object.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The proper return code is "-EOPNOTSUPP" when the modify_cq() callback is
not supported, all drivers should generate this and all users should check
for it when detecting not supported functionality.
Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Acked-by: Leon Romanovsky <leonro@mellanox.com> (for mlx5)
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This patch avoids that sparse reports the following warning:

drivers/infiniband/hw/cxgb4/qp.c:2269:34: warning: Using plain integer as NULL pointer
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Acked-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This patch avoids that sparse complains about casts to restricted __be32.

Fixes: a3cdaa69 ("cxgb4: Adds CPL support for Shared Receive Queues")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

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

drivers/infiniband/hw/cxgb4/cm.c:1860:5: warning: variable 'status' set but not used [-Wunused-but-set-variable]
  u8 status;
     ^~~~~~

Fixes: 6a0b6174 ("rdma/cxgb4: Add support for kernel mode SRQ's")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

In rdma cm module, functions which are common between IB and iWarp
are named with cma_.
iWarp specific functions are prefixed with cma_iw.
IB specific functions are perfixed with cma_ib.

However some functions in request processing path didn't follow
cma_ib notion. Prefix them with _ib for better code clarity.
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>

cma_add_one() initializes the default GID regardless of device type.
listen_id is bound to a device and an IP address, its GID type is
initialized by cma_acquire_dev().

Therefore a valid default GID type is always available, it is not needed
to check port type during cma_acquire_dev().

Initialize gid type of a cm id when the cm_id is created instead of
doing conditional checks during cma_acquire_dev() and trying to
initialize to 0 during _cma_attach_to_dev().
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>

In various functions rdma_cm_event is zero initialized on stack using
memset() while holding lock which is not necessary.
Therefore, don't hold the lock while initializing on stack.
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>

Return bool for following internal and inline functions as their
underlying APIs return bool too.

1. cma_zero_addr()
2. cma_loopback_addr()
3. cma_any_addr()
4. ib_addr_any()
5. ib_addr_loopback()

While we are touching cma_loopback_addr(), remove extra white spaces
in it.
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>

Arrange fields of cma_req_info structure for efficiency on
stack and get rid of one bit boolean field.
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>

Constify several pointers such as path_rec, ib_cm_event and listen_id
pointers in several functions.
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>

Following APIs are not supposed to modify addr or dest_addr contents.
Therefore make those function argument const for better code
readability.

1. rdma_resolve_ip()
2. rdma_addr_size()
3. rdma_resolve_addr()
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>

Currently dst address is first set and later on cleared on either of the
3 error conditions are met.
However none of the APIs or checks are supposed to refer to the
destination address of the cm_id.
Therefore, set the destination address after necessary checks pass which
simplifies the error flow.
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>

Currently rdma_cm_id's resource tracking fields such as owner task and
kern_name and other non resource tracking fields are initialized in
in single function __rdma_create_id().

Therefore, initialize rdma_cm_id's resource type also in same init
function.
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>