1. 31 Aug, 2017 2 commits
    • Roland Dreier's avatar
      IB/core: Add might_sleep() annotation to ib_init_ah_from_wc() · 79364227
      Roland Dreier authored
      For RoCE, ib_init_ah_from_wc() can follow the path
      
          ib_init_ah_from_wc() ->
            rdma_addr_find_l2_eth_by_grh() ->
              rdma_resolve_ip()
      
      and rdma_resolve_ip() will sleep in kzalloc() and wait_for_completion().
      
      However, developers will not see any warnings if they use ib_init_ah_from_wc()
      in an atomic context and test only on IB, because the function doesn't
      sleep in that case.
      
      Add a might_sleep() so that lockdep will catch bugs no matter what hardware is
      used to test.
      Signed-off-by: default avatarRoland Dreier <roland@purestorage.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      79364227
    • Roland Dreier's avatar
      IB/cm: Fix sleeping in atomic when RoCE is used · c7616118
      Roland Dreier authored
      A couple of places in the CM do
      
          spin_lock_irq(&cm_id_priv->lock);
          ...
          if (cm_alloc_response_msg(work->port, work->mad_recv_wc, &msg))
      
      However when the underlying transport is RoCE, this leads to a sleeping function
      being called with the lock held - the callchain is
      
          cm_alloc_response_msg() ->
            ib_create_ah_from_wc() ->
              ib_init_ah_from_wc() ->
                rdma_addr_find_l2_eth_by_grh() ->
                  rdma_resolve_ip()
      
      and rdma_resolve_ip() starts out by doing
      
          req = kzalloc(sizeof *req, GFP_KERNEL);
      
      not to mention rdma_addr_find_l2_eth_by_grh() doing
      
          wait_for_completion(&ctx.comp);
      
      to wait for the task that rdma_resolve_ip() queues up.
      
      Fix this by moving the AH creation out of the lock.
      Signed-off-by: default avatarRoland Dreier <roland@purestorage.com>
      Reviewed-by: default avatarSean Hefty <sean.hefty@intel.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      c7616118
  2. 30 Aug, 2017 2 commits
    • Matan Barak's avatar
      IB/core: Add support to finalize objects in one transaction · f43dbebf
      Matan Barak authored
      The new ioctl based infrastructure either commits or rollbacks
      all objects of the method as one transaction. In order to do
      that, we introduce a notion of dealing with a collection of
      objects that are related to a specific method.
      
      This also requires adding a notion of a method and attribute.
      A method contains a hash of attributes, where each bucket
      contains several attributes. The attributes are hashed according
      to their namespace which resides in the four upper bits of the id.
      
      For example, an object could be a CQ, which has an action of CREATE_CQ.
      This action has multiple attributes. For example, the CQ's new handle
      and the comp_channel. Each layer in this hierarchy - objects, methods
      and attributes is split into namespaces. The basic example for that is
      one namespace representing the default entities and another one
      representing the driver specific entities.
      
      When declaring these methods and attributes, we actually declare
      their specifications. When a method is executed, we actually
      allocates some space to hold auxiliary information. This auxiliary
      information contains meta-data about the required objects, such
      as pointers to their type information, pointers to the uobjects
      themselves (if exist), etc.
      The specification, along with the auxiliary information we allocated
      and filled is given to the finalize_objects function.
      Signed-off-by: default avatarMatan Barak <matanb@mellanox.com>
      Reviewed-by: default avatarYishai Hadas <yishaih@mellanox.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      f43dbebf
    • Matan Barak's avatar
      IB/core: Add a generic way to execute an operation on a uobject · a0aa309c
      Matan Barak authored
      The ioctl infrastructure treats all user-objects in the same manner.
      It gets objects ids from the user-space and by using the object type
      and type attributes mentioned in the object specification, it executes
      this required method. Passing an object id from the user-space as
      an attribute is carried out in three stages. The first is carried out
      before the actual handler and the last is carried out afterwards.
      
      The different supported operations are read, write, destroy and create.
      In the first stage, the former three actions just fetches the object
      from the repository (by using its id) and locks it. The last action
      allocates a new uobject. Afterwards, the second stage is carried out
      when the handler itself carries out the required modification of the
      object. The last stage is carried out after the handler finishes and
      commits the result. The former two operations just unlock the object.
      Destroy calls the "free object" operation, taking into account the
      object's type and releases the uobject as well. Creation just adds the
      new uobject to the repository, making the object visible to the
      application.
      
      In order to abstract these details from the ioctl infrastructure
      layer, we add uverbs_get_uobject_from_context and
      uverbs_finalize_object functions which corresponds to the first
      and last stages respectively.
      Signed-off-by: default avatarMatan Barak <matanb@mellanox.com>
      Reviewed-by: default avatarYishai Hadas <yishaih@mellanox.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      a0aa309c
  3. 29 Aug, 2017 11 commits
  4. 28 Aug, 2017 25 commits