Commits 71c29bd5c235 ("IB/uverbs: Add devnode method to set path/mode")
and c3af0980ce01 ("IB: Add devnode methods to cm_class and umad_class")
added devnode methods that set the mode.

However, these methods don't check for a NULL mode, and so we get a
crash when unloading modules because devtmpfs_delete_node() calls
device_get_devnode() with mode == NULL.

Add the missing checks.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.de>
[ Also fix cm.c.  - Roland ]
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  RDMA/cma: Save PID of ID's owner
  RDMA/cma: Add support for netlink statistics export
  RDMA/cma: Pass QP type into rdma_create_id()
  RDMA: Update exported headers list
  RDMA/cma: Export enum cma_state in <rdma/rdma_cm.h>
  RDMA/nes: Add a check for strict_strtoul()
  RDMA/cxgb3: Don't post zero-byte read if endpoint is going away
  RDMA/cxgb4: Use completion objects for event blocking
  IB/srp: Fix integer -> pointer cast warnings
  IB: Add devnode methods to cm_class and umad_class
  IB/mad: Return EPROTONOSUPPORT when an RDMA device lacks the QP required
  IB/uverbs: Add devnode method to set path/mode
  RDMA/ucma: Add .nodename/.mode to tell userspace where to create device node
  RDMA: Add netlink infrastructure
  RDMA: Add error handling to ib_core_init()

Save the PID associated with an RDMA CM ID for reporting via netlink.

Signed-off-by: Nir Muchtar <nirm@voltaire.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

Add callbacks and data types for statistics export of all current
devices/ids.  The schema for RDMA CM is a series of netlink messages.
Each one contains an rdma_cm_stat struct.  Additionally, two netlink
attributes are created for the addresses for each message (if
applicable).

Their types used are:
RDMA_NL_RDMA_CM_ATTR_SRC_ADDR (The source address for this ID)
RDMA_NL_RDMA_CM_ATTR_DST_ADDR (The destination address for this ID)
sockaddr_* structs are encapsulated within these attributes.

In other words, every transaction contains a series of messages like:

-------message 1-------
struct rdma_cm_id_stats {
       __u32 qp_num;
       __u32 bound_dev_if;
       __u32 port_space;
       __s32 pid;
       __u8 cm_state;
       __u8 node_type;
       __u8 port_num;
       __u8 reserved;
}
RDMA_NL_RDMA_CM_ATTR_SRC_ADDR attribute - contains the source address
RDMA_NL_RDMA_CM_ATTR_DST_ADDR attribute - contains the destination address
-------end 1-------
-------message 2-------
struct rdma_cm_id_stats
RDMA_NL_RDMA_CM_ATTR_SRC_ADDR attribute
RDMA_NL_RDMA_CM_ATTR_DST_ADDR attribute
-------end 2-------

Signed-off-by: Nir Muchtar <nirm@voltaire.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

The RDMA CM currently infers the QP type from the port space selected
by the user.  In the future (eg with RDMA_PS_IB or XRC), there may not
be a 1-1 correspondence between port space and QP type.  For netlink
export of RDMA CM state, we want to export the QP type to userspace,
so it is cleaner to explicitly associate a QP type to an ID.

Modify rdma_create_id() to allow the user to specify the QP type, and
use it to make our selections of datagram versus connected mode.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

Move cma.c's internal definition of enum cma_state to enum rdma_cm_state
in an exported header so that it can be exported via RDMA netlink.

Signed-off-by: Nir Muchtar <nirm@voltaire.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

We want the ucmX, umadX and issmX device nodes to show up under
/dev/infiniband, and additionally ucmX should have mode 0666.  Add
appropriate devnode methods to their class structs for this.

Signed-off-by: Roland Dreier <roland@purestorage.com>

We had a script which was looping through the devices returned from
ibstat and attempted to register a SMI agent on an ethernet device.
This caused a kernel panic for IBoE devices that don't have QP0.

Fix this by checking if the QP exists before using it.

Signed-off-by: Ira Weiny <weiny2@llnl.gov>
Acked-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

We want udev to create a device node under /dev/infiniband with
permission 0666 for uverbsX devices, so add a devnode method to set the
appropriate info.

Signed-off-by: Roland Dreier <roland@purestorage.com>