When a GID entry is invalid EAGAIN is returned. This is an incorrect error
code, there is nothing that will make this GID entry valid again in
bounded time.

Some user space tools fail incorrectly if EAGAIN is returned here, and
this represents a small ABI change from earlier kernels.

The first patch in the Fixes list makes entries that were valid before
to become invalid, allowing this code to trigger, while the second patch
in the Fixes list introduced the wrong EAGAIN.

Therefore revert the return result to EINVAL which matches the historical
expectations of the ibv_query_gid_type() API of the libibverbs user space
library.

Cc: <stable@vger.kernel.org>
Fixes: 598ff6ba ("IB/core: Refactor GID modify code for RoCE")
Fixes: 03db3a2d ("IB/core: Add RoCE GID table management")
Reviewed-by: NDaniel Jurgens <danielj@mellanox.com>
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Before [1], When MAC address of the netdevice is changed, default GID is
supposed to get deleted and added back which affects the node and/or port
GUID in below sequence.

netdevice_event()
-> NETDEV_CHANGEADDR
   default_del_cmd()
      del_netdev_default_ips()
          bond_delete_netdev_default_gids()
              ib_cache_gid_set_default_gid()
                  ib_cache_gid_del()
   add_cmd()
   [..]

However, ib_cache_gid_del() was not getting invoked in non bonding
scenarios because event_ndev and rdma_ndev are same.
Therefore, fix such condition to ignore checking upper device when event
ndev and rdma_dev are same; similar to bond_set_netdev_default_gids().

Which this fix ib_cache_gid_del() is invoked correctly; however
ib_cache_gid_del() doesn't find the default GID for deletion because
find_gid() was given default_gid = false with
GID_ATTR_FIND_MASK_DEFAULT set.
But it was getting overwritten by ib_cache_gid_set_default_gid() later
on as part of add_cmd().
Therefore, mac address change used to work for default GID.

With refactor series [1], this incorrect behavior is detected.

Therefore,
when deleting default GID, set default_gid and set MASK flag.
when deleting IP based GID, clear default_gid and set MASK flag.

[1] https://patchwork.kernel.org/patch/10319151/

Fixes: 238fdf48 ("IB/core: Add RoCE table bonding support")
Fixes: 598ff6ba ("IB/core: Refactor GID modify code for RoCE")
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When IPv6 link local address is removed, if it matches with the default
GID, default GID(s)s gets removed which may not be a desired behavior.
This behavior is introduced by refactor work in Fixes tag.

When IPv6 link address is removed, removing its equivalent RoCEv2 GID
which exactly matches with default RoCEv2 GID, is right thing to do.
However achieving it correctly requires lot more changes, likely in
roce_gid_mgmt.c and core/cache.c. This should be done as independent
patch.

Therefore, this patch preserves behavior of not deleteing default GIDs.
This is done by providing explicit hint to consider default GID property
using mask and default_gid; similar to add_gid().

Fixes: 598ff6ba ("IB/core: Refactor GID modify code for RoCE")
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Default GIDs are marked reserved at the start of the GID table at index
0 and 1 by gid_table_reserve_default().  Currently when default GID is
requested, it can still allocates an empty slot which was not marked as
RESERVED for default GID, which is incorrect.

At least in current code flow of roce_gid_mgmt.c, in theory we can
still request to allocate more than one/two default GIDs depending
on how upper devices are setup.

Therefore, it is better for cache layer to only allow our reserved slots
to be used by default GID allocation requests.

Fixes: 598ff6ba ("IB/core: Refactor GID modify code for RoCE")
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Now that ib_gid_attr contains device, port and index, simplify the
provider APIs add_gid() and del_gid() to use device, port and index
fields from the ib_gid_attr attributes structure.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Code is refactored to prepare separate functions for RoCE which can do more
complex operations related to reference counting, while still
maintainining code readability. This includes
(a) Simplification to not perform netdevice checks and modifications
for IB link layer.
(b) Do not add RoCE GID entry which has NULL netdevice; instead return
an error.
(c) If GID addition fails at provider level add_gid(), do not add the
entry in the cache and keep the entry marked as INVALID.
(d) Simplify and reuse the ib_cache_gid_add()/del() routines so that they
can be used even for modifying default GIDs. This avoid some code
duplication in modifying default GIDs.
(e) find_gid() routine refers to the data entry flags to qualify a GID
as valid or invalid GID rather than depending on attributes and zeroness
of the GID content.
(f) gid_table_reserve_default() sets the GID default attribute at
beginning while setting up the GID table. There is no need to use
default_gid flag in low level functions such as write_gid(), add_gid(),
del_gid(), as they never need to update the DEFAULT property of the GID
entry while during GID table update.

As as result of this refactor, reserved GID 0:0:0:0:0:0:0:0 is no longer
searchable as described below.

A unicast GID entry of 0:0:0:0:0:0:0:0 is Reserved GID as per the IB
spec version 1.3 section 4.1.1, point (6) whose snippet is below.

"The unicast GID address 0:0:0:0:0:0:0:0 is reserved - referred to as
the Reserved GID. It shall never be assigned to any endport. It shall
not be used as a destination address or in a global routing header
(GRH)."

GID table cache now only stores valid GID entries. Before this patch,
Reserved GID 0:0:0:0:0:0:0:0 was searchable in the GID table using
ib_find_cached_gid_by_port() and other similar find routines.

Zero GID is no longer searchable as it shall not to be present in GRH or
path recored entry as described in IB spec version 1.3 section 4.1.1,
point (6), section 12.7.10 and section 12.7.20.

ib_cache_update() is simplified to check link layer once, use unified
locking scheme for all link layers, removed temporary gid table
allocation/free logic.

Additionally,
(a) Expand ib_gid_attr to store port and index so that GID query
routines can get port and index information from the attribute structure.
(b) Expand ib_gid_attr to store device as well so that in future code when
GID reference counting is done, device is used to reach back to the GID
table entry.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Currently following inconsistencies exist.
1. ib_query_gid() returns GID from the software cache for a RoCE port
and returns GID from the HCA for an IB port.
This is incorrect because software GID cache is maintained regardless
of HCA port type.

2. GID is queries from the HCA via ib_query_gid and updated in the
software cache for IB link layer. Both of them might not be in sync.

ULPs such as SRP initiator, SRP target, IPoIB driver have historically
used ib_query_gid() API to query the GID. However CM used cached version
during CM processing, When software cache was introduced, this
inconsitency remained.

In order to simplify, improve readability and avoid link layer
specific above inconsistencies, this patch brings following changes.

1. ib_query_gid() always refers to the cache layer regardless of link
layer.

2. cache module who reads the GID entry from HCA and builds the cache,
directly invokes the HCA provider verb's query_gid() callback function.

3. ib_query_port() is being called in early stage where GID cache is not
yet build while reading port immutable property. Therefore it needs to
read the default GID from the HCA for IB link layer to publish the
subnet prefix.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

IB core maintains the GID cache entries for the GID table.
This cache table has to be maintained regardless of HCA's
support of GID table.
For IB and iWarp ports, cache is created by querying the HCA.
For RoCE cache is created based on netdev events.

Therefore just refer to the RoCE port property of the {device, port} to
decide whether to build cache by querying HCA or from netdev events.
There is no need to check if HCA support GID table or not.

ib_cache_update() referred to RoCE attribute before validating
port. Though in all current callers port is valid, it is incorrect
to query RoCE port property before validating the port. Therefore,
rdma_protocol_roce() check is done after rdma_is_port_valid() verifies
that port is valid.

Fixes: 115b68aa ("IB/ocrdma: Removed GID add/del null routines")
Reviewed-by: NDaniel Jurgens <danielj@mellanox.com>
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

ib_find_gid_by_filter() searches GID with filter only for RoCE link
layer regardless of HCA's support for GID table.
Therefore, right way to lookup is compare RoCE port property and not
the GID table property.

Fixes: 99b27e3b ("IB/cache: Add ib_find_gid_by_filter cache API")
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Due to following reasons, GID table event is generated regardless of GID
table property.

1. GID table cache is maintained at ib core layer regardless of link layer.
2. GID change event has no relation with IB link layer.
3. GID change event also doesn't depend on whether HCA supports GID table
or not.

Fixes: f3906bd3 ("IB/core: Refactor GID cache's ib_dispatch_event")
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Use rdma_is_port_valid() which performs port validity check instead of
open coding the same check.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Reviewed-by: NYuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Exported symbol's comments should be with function definition and not in
the header file. Therefore comments of ib_find_cached_gid() and
ib_find_cached_gid_by_port() functions are moved closer to their
definitions.

The function name in then comment is different than the actual function
name, fix it to be same as ib_cache_gid_find_by_filter().

Also current comment section of ib_find_cached_gid_by_port() contains the
desciption of ib_find_cached_gid(), fix that as well.
Reviewed-by: NDaniel Jurgens <danielj@mellanox.com>
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

When mlx5_ib_add is called determine if the mlx5 core device being
added is capable of dual port RoCE operation. If it is, determine
whether it is a master device or a slave device using the
num_vhca_ports and affiliate_nic_vport_criteria capabilities.

If the device is a slave, attempt to find a master device to affiliate it
with. Devices that can be affiliated will share a system image guid. If
none are found place it on a list of unaffiliated ports. If a master is
found bind the port to it by configuring the port affiliation in the NIC
vport context.

Similarly when mlx5_ib_remove is called determine the port type. If it's
a slave port, unaffiliate it from the master device, otherwise just
remove it from the unaffiliated port list.

The IB device is registered as a multiport device, even if a 2nd port is
not available for affiliation. When the 2nd port is affiliated later the
GID cache must be refreshed in order to get the default GIDs for the 2nd
port in the cache. Export roce_rescan_device to provide a mechanism to
refresh the cache after a new port is bound.

In a multiport configuration all IB object (QP, MR, PD, etc) related
commands should flow through the master mlx5_core_dev, other commands
must be sent to the slave port mlx5_core_mdev, an interface is provide
to get the correct mdev for non IB object commands.
Signed-off-by: NDaniel Jurgens <danielj@mellanox.com>
Reviewed-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leon@kernel.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

It always returns 0. Change return type to void.
Signed-off-by: NDaniel Jurgens <danielj@mellanox.com>
Reviewed-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leon@kernel.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

ib_find_gid_by_filter() is used only by ib_core, therefore avoid
exporting it.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Reviewed-by: NDaniel Jurgens <danielj@mellanox.com>
Signed-off-by: NLeon Romanovsky <leon@kernel.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Currently on every gid entry comparison miss found variable is checked;
which is not needed as those two comparison fail already indicate that
GID is not found yet.
So refactor to avoid such check and copy the GID index when found.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Reviewed-by: NDaniel Jurgens <danielj@mellanox.com>
Signed-off-by: NLeon Romanovsky <leon@kernel.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The functions ib_register_event_handler() and
ib_unregister_event_handler() always returned success and they can't fail.

Let's convert those functions to be void, remove redundant checks and
cleanup tons of goto statements.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add new LSM hooks to allocate and free security contexts and check for
permission to access a PKey.

Allocate and free a security context when creating and destroying a QP.
This context is used for controlling access to PKeys.

When a request is made to modify a QP that changes the port, PKey index,
or alternate path, check that the QP has permission for the PKey in the
PKey table index on the subnet prefix of the port. If the QP is shared
make sure all handles to the QP also have access.

Store which port and PKey index a QP is using. After the reset to init
transition the user can modify the port, PKey index and alternate path
independently. So port and PKey settings changes can be a merge of the
previous settings and the new ones.

In order to maintain access control if there are PKey table or subnet
prefix change keep a list of all QPs are using each PKey index on
each port. If a change occurs all QPs using that device and port must
have access enforced for the new cache settings.

These changes add a transaction to the QP modify process. Association
with the old port and PKey index must be maintained if the modify fails,
and must be removed if it succeeds. Association with the new port and
PKey index must be established prior to the modify and removed if the
modify fails.

1. When a QP is modified to a particular Port, PKey index or alternate
   path insert that QP into the appropriate lists.

2. Check permission to access the new settings.

3. If step 2 grants access attempt to modify the QP.

4a. If steps 2 and 3 succeed remove any prior associations.

4b. If ether fails remove the new setting associations.

If a PKey table or subnet prefix changes walk the list of QPs and
check that they have permission. If not send the QP to the error state
and raise a fatal error event. If it's a shared QP make sure all the
QPs that share the real_qp have permission as well. If the QP that
owns a security structure is denied access the security structure is
marked as such and the QP is added to an error_list. Once the moving
the QP to error is complete the security structure mark is cleared.

Maintaining the lists correctly turns QP destroy into a transaction.
The hardware driver for the device frees the ib_qp structure, so while
the destroy is in progress the ib_qp pointer in the ib_qp_security
struct is undefined. When the destroy process begins the ib_qp_security
structure is marked as destroying. This prevents any action from being
taken on the QP pointer. After the QP is destroyed successfully it
could still listed on an error_list wait for it to be processed by that
flow before cleaning up the structure.

If the destroy fails the QPs port and PKey settings are reinserted into
the appropriate lists, the destroying flag is cleared, and access control
is enforced, in case there were any cache changes during the destroy
flow.

To keep the security changes isolated a new file is used to hold security
related functionality.
Signed-off-by: NDaniel Jurgens <danielj@mellanox.com>
Acked-by: NDoug Ledford <dledford@redhat.com>
[PM: merge fixup in ib_verbs.h and uverbs_cmd.c]
Signed-off-by: NPaul Moore <paul@paul-moore.com>

Cache the subnet prefix and add a function to access it. Enforcing
security requires frequent queries of the subnet prefix and the pkeys in
the pkey table.
Signed-off-by: NDaniel Jurgens <danielj@mellanox.com>
Reviewed-by: NEli Cohen <eli@mellanox.com>
Reviewed-by: NLeon Romanovsky <leonro@mellanox.com>
Reviewed-by: NJames Morris <james.l.morris@oracle.com>
Acked-by: NDoug Ledford <dledford@redhat.com>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

Signed-off-by: NYuval Shaia <yuval.shaia@oracle.com>
Reviewed-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

As Jason suggested, we have 4 elements for per port arrays,
it's better to have a separate structure to represent them.

It simplifies code a bit, ~ 30 lines of code less :)
Signed-off-by: NJack Wang <jinpu.wang@profitbricks.com>
Reviewed-by: NMichael Wang <yun.wang@profitbricks.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Export function for rdma_cm, patch for rdma_cm to follow.
Signed-off-by: NJack Wang <jinpu.wang@profitbricks.com>
Reviewed-by: NMichael Wang <yun.wang@profitbricks.com>
Acked-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

We need a port state cache in ib_core, later we will use in rdma_cm.
Signed-off-by: NJack Wang <jinpu.wang@profitbricks.com>
Reviewed-by: NMichael Wang <yun.wang@profitbricks.com>
Acked-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The failure in ib_cache_setup_one function during
ib_register_device will leave leaked allocated memory.

Fixes: 03db3a2d ("IB/core: Add RoCE GID table management")
Signed-off-by: NLeon Romanovsky <leon@kernel.org>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Currently, when the netdevice returned by get_netdev is unregistered,
we delete all GIDs (including the default GIDs) and reset their
attributes. Therefore, when we re-register it, no default GIDs
will be assigned (as their "default GID") attribute will be reset.
Fixing this by keeping "default GID" attribute.

Fixes: 03db3a2d ('IB/core: Add RoCE GID table management')
Signed-off-by: NTalat Batheesh <talatb@mellanox.com>
Signed-off-by: NLeon Romanovsky <leon@kernel.org>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When deleting a default GID from the cache, its gid_type field is set
to 0.

This could set the gid_type to RoCE v1 for a RoCE v2 default GID,
essentially making it inaccessible to future modifications, since it
is no longer found by find_gid().

This fix preserves the gid_type value for default gids during cache
operations.

Fixes: b39ffa1d ('IB/core: Add gid_type to gid attribute')
Signed-off-by: NAviv Heller <avivh@mellanox.com>
Signed-off-by: NLeon Romanovsky <leon@kernel.org>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When we fail to find the default gid index, we can't continue
processing in this routine or else we will pass a negative
index to later routines resulting in invalid memory access
attempts and a kernel oops.

Fixes: 03db3a2d (IB/core: Add RoCE GID table management)
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When we fail to find the default gid index, we can't continue
processing in this routine or else we will pass a negative
index to later routines resulting in invalid memory access
attempts and a kernel oops.

Fixes: 03db3a2d (IB/core: Add RoCE GID table management)
Signed-off-by: NDoug Ledford <dledford@redhat.com>

1. Replaced printk with appropriate pr_warn, pr_err, pr_info.
2. Removed unnecessary prints around memory allocation failure
which are not required, as reported by the checkpatch script.
Signed-off-by: NParav Pandit <pandit.parav@gmail.com>
Reviewed-by: NHaggai Eran <haggaie@mellanox.com>
Reviewed-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When write_gid function needs to do a sleep-able operation, it unlocks
table->rwlock and then relocks it. Sparse complains about context
imbalance.

This is safe as write_gid is always called with table->rwlock.
write_gid protects from simultaneous writes to this GID entry
by setting the GID_TABLE_ENTRY_INVALID flag.

Fixes: 9c584f04 ('IB/core: Change per-entry lock in RoCE GID table to
		     one lock')
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Users would like to control the behaviour of rdma_cm.
For example, old applications which don't set the
required RoCE gid type could be executed on RoCE V2
network types. In order to support this configuration,
we implement a configfs for rdma_cm.

In order to use the configfs, one needs to mount it and
mkdir <IB device name> inside rdma_cm directory.

The patch adds support for a single configuration file,
default_roce_mode. The mode can either be "IB/RoCE v1" or
"RoCE v2".
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Adding RoCE v2 GID type and port type. Vendors
which support this type will get their GID table
populated with RoCE v2 GIDs automatically.
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

In order to support multiple GID types, we need to store the gid_type
with each GID. This is also aligned with the RoCE v2 annex "RoCEv2 PORT
GID table entries shall have a "GID type" attribute that denotes the L3
Address type". The currently supported GID is IB_GID_TYPE_IB which is
also RoCE v1 GID type.

This implies that gid_type should be added to roce_gid_table meta-data.
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Previously, we've searched the GID table twice: first when we searched
the table for a GID matching the proposed new one, and second when we
didn't find a match, we searched again for an empty GID slot in the
table.  Instead, search the table once noting the first empty slot as
we search for our target GID.
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Reviewed-by: NHaggai Eran <haggaie@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Previously, IB GID cached used a lock per entry. This could result
in spending a lot of CPU cycles for locking and unlocking just
in order to find a GID. Changing this in favor of one lock per
a GID table.
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Reviewed-by: NHaggai Eran <haggaie@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Refactor ib_dispatch_event into a new function in order to avoid
duplicating code in the next patch.
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Reviewed-by: NHaggai Eran <haggaie@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

GID cache API users might want to search for GIDs with specific
attributes rather than just specifying GID, net device and port.
This is used in a later patch, where we find the sgid index by
L2 Ethernet attributes.
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Reviewed-By: NDevesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Sometime consumers might want to search for a GID in a specific port.
For example, when a WC arrives and we want to search the GID
that matches that port - it's better to search only the relevant
port.
Exposing and renaming ib_cache_gid_find_by_port in order to match
the naming convention of the module.
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Adding an ability to query the IB cache by a netdev and get the
attributes of a GID. These parameters are necessary in order to
successfully resolve the required GID (when the netdevice is known)
and get the Ethernet L2 attributes from a GID.
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Reviewed-By: NDevesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When ib_cache_gid_set_default_gid is called from several threads,
updating the table could make find_gid fail, therefore a negative
index will be retruned and an invalid table entry will be used.
Locking find_gid as well fixes this problem.

Fixes: 03db3a2d ('IB/core: Add RoCE GID table management')
Signed-off-by: NDoron Tsur <doront@mellanox.com>
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>