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: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJason 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: NJason 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: NJason 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: NJason 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: NJason Gunthorpe <jgg@mellanox.com>

This patch considers the case that ib_flow is created by some device
driver with its specific parameters using the KABI infrastructure.

In that case both QP and ib_uflow_resources might not be applicable.
Downstream patches from this series use the above functionality.
Signed-off-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Userspace also needs to know if the port requires GRHs to properly form
the AVs it creates.
Signed-off-by: NArtemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

The internal flag IP_BASED_GIDS was added to a field that was being used
to hold the port Info CapabilityMask without considering the effects this
will have. Since most drivers just use the value from the HW MAD it means
IP_BASED_GIDS will also become set on any HW that sets the IBA flag
IsOtherLocalChangesNoticeSupported - which is not intended.

Fix this by keeping port_cap_flags only for the IBA CapabilityMask value
and store unrelated flags externally. Move the bit definitions for this to
ib_mad.h to make it clear what is happening.

To keep the uAPI unchanged define a new set of flags in the uapi header
that are only used by ib_uverbs_query_port_resp.port_cap_flags which match
the current flags supported in rdma-core, and the values exposed by the
current kernel.

Fixes: b4a26a27 ("IB: Report using RoCE IP based gids in port caps")
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NArtemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

Now that ib_uobject has a ib_uverbs_file we don't need this extra one in
ib_ucq_object.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The only purpose for this structure was to hold the ib_uobject_file
pointer, but now that is part of the standard ib_uobject the structure
no longer makes any sense, so get rid of it.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

The ucontext isn't needed any more, just pass the uverbs_file directly.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

The IDR is part of the ib_ufile so all the machinery to lock it, handle
closing and disassociation rightly belongs to the ufile not the ucontext.

This changes the lifetime of that data to match the lifetime of the file
descriptor which is always strictly longer than the lifetime of the
ucontext.

We need the entire locking machinery to continue to exist after ucontext
destruction to allow us to return the destroy data after a device has been
disassociated.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

This consolidates a bunch of repeated code patterns into a helper.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@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>

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>

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>

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>

This patch replaces the ib_device_attr.max_sge with max_send_sge and
max_recv_sge. It allows ulps to take advantage of devices that have very
different send and recv sge depths.  For example cxgb4 has a max_recv_sge
of 4, yet a max_send_sge of 16.  Splitting out these attributes allows
much more efficient use of the SQ for cxgb4 with ulps that use the RDMA_RW
API. Consider a large RDMA WRITE that has 16 scattergather entries.
With max_sge of 4, the ulp would send 4 WRITE WRs, but with max_sge of
16, it can be done with 1 WRITE WR.
Acked-by: NSagi Grimberg <sagi@grimberg.me>
Acked-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NSelvin Xavier <selvin.xavier@broadcom.com>
Acked-by: NShiraz Saleem <shiraz.saleem@intel.com>
Acked-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Since we are adding some new fields to this structure it is safest if all
users reliably initialize the struct to zero.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

Simplify the flow_resources_alloc() function call by reducing
number of goto statements.
Reviewed-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>

The flows were hidden from the C compiler; expose them as a zero-length
array to allow struct_size to work.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: NKees Cook <keescook@chromium.org>

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
    int stuff;
    void *entry[];
};

instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);

This patch makes the changes for kmalloc()-family (and kvmalloc()-family)
uses. It was done via automatic conversion with manual review for the
"CHECKME" non-standard cases noted below, using the following Coccinelle
script:

// pkey_cache = kmalloc(sizeof *pkey_cache + tprops->pkey_tbl_len *
//                      sizeof *pkey_cache->table, GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@

- alloc(sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
+ alloc(CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)
Signed-off-by: NKees Cook <keescook@chromium.org>

The struct ib_uverbs_flow_spec_action_count associates a counters object
with the flow.

Post this association the flow counters can be read via the counters
object.
Reviewed-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NRaed Salem <raeds@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

This is required when user-space drivers need to pass extra information
regarding how to handle this flow steering specification.
Reviewed-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NBoris Pismenny <borisp@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Add a new MPLS steering match filter that can match against
a single MPLS tag field.

Since the MPLS header can reside in different locations in the packet's
protocol stack as well as be encapsulated with a tunnel protocol, it
is required to know the exact location of the header in the protocol
stack.

Therefore, when including the MPLS protocol spec in the specs list,
it is mandatory to provide the list in an ordered manner, so
that it represents the actual header order in a matching packet.

Drivers that process the spec list and apply the matching rule
should treat the position of the MPLS spec in the spec list as the
actual location of the MPLS label in the packet's protocol stack.
Reviewed-by: NMark Bloch <markb@mellanox.com>
Signed-off-by: NAriel Levkovich <lariel@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Adding a new GRE steering match filter that can match against
key and protocol fields.
Reviewed-by: NMark Bloch <markb@mellanox.com>
Signed-off-by: NAriel Levkovich <lariel@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

This patch fixes a crash that happens due to access to an
uninitialized DM pointer within the MR object.

The change makes sure the DM pointer in the MR object is set to
NULL during a non-DM MR creation to prevent a false indication
that this MR is related to a DM in the dereg flow.

Fixes: be934cca ("IB/uverbs: Add device memory registration ioctl support")
Reported-by: NLijun Ou <oulijun@huawei.com>
Signed-off-by: NAriel Levkovich <lariel@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch adds a check in the ib_uverbs_rereg_mr flow to make
sure there's no attempt to rereg a device memory MR to regular MR.
In such case the command will fail with -EINVAL status.

fixes: be934cca ("IB/uverbs: Add device memory registration ioctl support")
Signed-off-by: NAriel Levkovich <lariel@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This change allows vendors to report device memory capability
max_dm_size - to user via uverbs command.
Signed-off-by: NAriel Levkovich <lariel@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Adding a new ESP steering match filter that could match against
spi and seq used in IPSec protocol.
Reviewed-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Binding a flow_action to flow steering rule requires using a new
specification. Therefore, adding such an IB_FLOW_SPEC_ACTION_HANDLE flow
specification.

Flow steering rules could use flow_action(s) and as of that we need to
avoid deleting flow_action(s) as long as they're being used.
Moreover, when the attached rules are deleted, action_handle reference
count should be decremented. Introducing a new mechanism of flow
resources to keep track on the attached action_handle(s). Later on, this
mechanism should be extended to other attached flow steering resources
like flow counters.
Reviewed-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The current implementation of kern_spec_to_ib_spec_filter, which takes
a uAPI based flow steering specification and creates the respective kernel
API flow steering structure, gets a ib_uverbs_flow_spec structure.
The new flow_action uAPI gets a match mask and filter from user-space
which aren't encoded in the flow steering's ib_uverbs_flow_spec structure.
Exporting the logic out of kern_spec_to_ib_spec_filter to get user-space
blobs rather than ib_uverbs_flow_spec structure.
Reviewed-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

This is already used in many places, get the rest of them too, only
to make the code a bit clearer & simpler.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Use macros to make names consistent in ioctl() uAPI:
The ioctl() uAPI works with object-method hierarchy. The method part
also states which handler should be executed when this method is called
from user-space. Therefore, we need to tie method, method's id, method's
handler and the object owning this method together.
Previously, this was done through explicit developer chosen names.
This makes grepping the code harder. Changing the method's name,
method's handler and object's name to be automatically generated based
on the ids.

The headers are split in a way so they be included and used by
user-space. One header strictly contains structures that are used
directly by user-space applications, where another header is used for
internal library (i.e. libibverbs) to form the ioctl() commands.
Other header simply contains the required general command structure.
Reviewed-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The QP state is internal enum which is checked at the driver
level by calling to ib_modify_qp_is_ok(). Move this check closer
to user and leave kernel users to be checked by compiler.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Implement the RDMA nldev netlink interface for dumping detailed
MR information.
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Reviewed-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Attempt to modify XRC_TGT QP type from the user space (ibv_xsrq_pingpong
invocation) will trigger the following kernel panic. It is caused by the
fact that such QPs missed uobject initialization.

[   17.408845] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
[   17.412645] IP: rdma_lookup_put_uobject+0x9/0x50
[   17.416567] PGD 0 P4D 0
[   17.419262] Oops: 0000 [#1] SMP PTI
[   17.422915] CPU: 0 PID: 455 Comm: ibv_xsrq_pingpo Not tainted 4.16.0-rc1+ #86
[   17.424765] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[   17.427399] RIP: 0010:rdma_lookup_put_uobject+0x9/0x50
[   17.428445] RSP: 0018:ffffb8c7401e7c90 EFLAGS: 00010246
[   17.429543] RAX: 0000000000000000 RBX: ffffb8c7401e7cf8 RCX: 0000000000000000
[   17.432426] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
[   17.437448] RBP: 0000000000000000 R08: 00000000000218f0 R09: ffffffff8ebc4cac
[   17.440223] R10: fffff6038052cd80 R11: ffff967694b36400 R12: ffff96769391f800
[   17.442184] R13: ffffb8c7401e7cd8 R14: 0000000000000000 R15: ffff967699f60000
[   17.443971] FS:  00007fc29207d700(0000) GS:ffff96769fc00000(0000) knlGS:0000000000000000
[   17.446623] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   17.448059] CR2: 0000000000000048 CR3: 000000001397a000 CR4: 00000000000006b0
[   17.449677] Call Trace:
[   17.450247]  modify_qp.isra.20+0x219/0x2f0
[   17.451151]  ib_uverbs_modify_qp+0x90/0xe0
[   17.452126]  ib_uverbs_write+0x1d2/0x3c0
[   17.453897]  ? __handle_mm_fault+0x93c/0xe40
[   17.454938]  __vfs_write+0x36/0x180
[   17.455875]  vfs_write+0xad/0x1e0
[   17.456766]  SyS_write+0x52/0xc0
[   17.457632]  do_syscall_64+0x75/0x180
[   17.458631]  entry_SYSCALL_64_after_hwframe+0x21/0x86
[   17.460004] RIP: 0033:0x7fc29198f5a0
[   17.460982] RSP: 002b:00007ffccc71f018 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   17.463043] RAX: ffffffffffffffda RBX: 0000000000000078 RCX: 00007fc29198f5a0
[   17.464581] RDX: 0000000000000078 RSI: 00007ffccc71f050 RDI: 0000000000000003
[   17.466148] RBP: 0000000000000000 R08: 0000000000000078 R09: 00007ffccc71f050
[   17.467750] R10: 000055b6cf87c248 R11: 0000000000000246 R12: 00007ffccc71f300
[   17.469541] R13: 000055b6cf8733a0 R14: 0000000000000000 R15: 0000000000000000
[   17.471151] Code: 00 00 0f 1f 44 00 00 48 8b 47 48 48 8b 00 48 8b 40 10 e9 0b 8b 68 00 90 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 53 89 f5 <48> 8b 47 48 48 89 fb 40 0f b6 f6 48 8b 00 48 8b 40 20 e8 e0 8a
[   17.475185] RIP: rdma_lookup_put_uobject+0x9/0x50 RSP: ffffb8c7401e7c90
[   17.476841] CR2: 0000000000000048
[   17.477764] ---[ end trace 1dbcc5354071a712 ]---
[   17.478880] Kernel panic - not syncing: Fatal exception
[   17.480277] Kernel Offset: 0xd000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)

Fixes: 2f08ee36 ("RDMA/restrack: don't use uaccess_kernel()")
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

uaccess_kernel() isn't sufficient to determine if an rdma resource is
user-mode or not.  For example, resources allocated in the add_one()
function of an ib_client get falsely labeled as user mode, when they
are kernel mode allocations.  EG: mad qps.

The result is that these qps are skipped over during a nldev query
because of an erroneous namespace mismatch.

So now we determine if the resource is user-mode by looking at the object
struct's uobject or similar pointer to know if it was allocated for user
mode applications.

Fixes: 02d8883f ("RDMA/restrack: Add general infrastructure to track RDMA resources")
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Update all the flows to ensure that function pointer exists prior
to accessing it.

This is much safer than checking the uverbs_ex_mask variable, especially
since we know that test isn't working properly and will be removed
in -next.

This prevents a user triggereable oops.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>