drivers/infiniband/core/rdma_core.h

   1 /*
   2  * Copyright (c) 2005 Topspin Communications.  All rights reserved.
   3  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
   4  * Copyright (c) 2005-2017 Mellanox Technologies. All rights reserved.
   5  * Copyright (c) 2005 Voltaire, Inc. All rights reserved.
   6  * Copyright (c) 2005 PathScale, Inc. All rights reserved.
   7  *
   8  * This software is available to you under a choice of one of two
   9  * licenses.  You may choose to be licensed under the terms of the GNU
  10  * General Public License (GPL) Version 2, available from the file
  11  * COPYING in the main directory of this source tree, or the
  12  * OpenIB.org BSD license below:
  13  *
  14  *     Redistribution and use in source and binary forms, with or
  15  *     without modification, are permitted provided that the following
  16  *     conditions are met:
  17  *
  18  *      - Redistributions of source code must retain the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer.
  21  *
  22  *      - Redistributions in binary form must reproduce the above
  23  *        copyright notice, this list of conditions and the following
  24  *        disclaimer in the documentation and/or other materials
  25  *        provided with the distribution.
  26  *
  27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  28  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  29  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  30  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  31  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  32  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  33  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  34  * SOFTWARE.
  35  */
  36
  37 #ifndef RDMA_CORE_H
  38 #define RDMA_CORE_H
  39
  40 #include <linux/idr.h>
  41 #include <rdma/uverbs_types.h>
  42 #include <rdma/uverbs_ioctl.h>
  43 #include <rdma/ib_verbs.h>
  44 #include <linux/mutex.h>
  45
  46 int uverbs_ns_idx(u16 *id, unsigned int ns_count);
  47 const struct uverbs_object_spec *uverbs_get_object(const struct ib_device *ibdev,
  48                                                    uint16_t object);
  49 const struct uverbs_method_spec *uverbs_get_method(const struct uverbs_object_spec *object,
  50                                                    uint16_t method);
  51 /*
  52  * These functions initialize the context and cleanups its uobjects.
  53  * The context has a list of objects which is protected by a mutex
  54  * on the context. initialize_ucontext should be called when we create
  55  * a context.
  56  * cleanup_ucontext removes all uobjects from the context and puts them.
  57  */
  58 void uverbs_cleanup_ucontext(struct ib_ucontext *ucontext, bool device_removed);
  59 void uverbs_initialize_ucontext(struct ib_ucontext *ucontext);
  60
  61 /*
  62  * uverbs_uobject_get is called in order to increase the reference count on
  63  * an uobject. This is useful when a handler wants to keep the uobject's memory
  64  * alive, regardless if this uobject is still alive in the context's objects
  65  * repository. Objects are put via uverbs_uobject_put.
  66  */
  67 void uverbs_uobject_get(struct ib_uobject *uobject);
  68
  69 /*
  70  * In order to indicate we no longer needs this uobject, uverbs_uobject_put
  71  * is called. When the reference count is decreased, the uobject is freed.
  72  * For example, this is used when attaching a completion channel to a CQ.
  73  */
  74 void uverbs_uobject_put(struct ib_uobject *uobject);
  75
  76 /* Indicate this fd is no longer used by this consumer, but its memory isn't
  77  * necessarily released yet. When the last reference is put, we release the
  78  * memory. After this call is executed, calling uverbs_uobject_get isn't
  79  * allowed.
  80  * This must be called from the release file_operations of the file!
  81  */
  82 void uverbs_close_fd(struct file *f);
  83
  84 /*
  85  * Get an ib_uobject that corresponds to the given id from ucontext, assuming
  86  * the object is from the given type. Lock it to the required access when
  87  * applicable.
  88  * This function could create (access == NEW), destroy (access == DESTROY)
  89  * or unlock (access == READ || access == WRITE) objects if required.
  90  * The action will be finalized only when uverbs_finalize_object or
  91  * uverbs_finalize_objects are called.
  92  */
  93 struct ib_uobject *uverbs_get_uobject_from_context(const struct uverbs_obj_type *type_attrs,
  94                                                    struct ib_ucontext *ucontext,
  95                                                    enum uverbs_obj_access access,
  96                                                    int id);
  97 int uverbs_finalize_object(struct ib_uobject *uobj,
  98                            enum uverbs_obj_access access,
  99                            bool commit);
 100 /*
 101  * Note that certain finalize stages could return a status:
 102  *   (a) alloc_commit could return a failure if the object is committed at the
 103  *       same time when the context is destroyed.
 104  *   (b) remove_commit could fail if the object wasn't destroyed successfully.
 105  * Since multiple objects could be finalized in one transaction, it is very NOT
 106  * recommended to have several finalize actions which have side effects.
 107  * For example, it's NOT recommended to have a certain action which has both
 108  * a commit action and a destroy action or two destroy objects in the same
 109  * action. The rule of thumb is to have one destroy or commit action with
 110  * multiple lookups.
 111  * The first non zero return value of finalize_object is returned from this
 112  * function. For example, this could happen when we couldn't destroy an
 113  * object.
 114  */
 115 int uverbs_finalize_objects(struct uverbs_attr_bundle *attrs_bundle,
 116                             struct uverbs_attr_spec_hash * const *spec_hash,
 117                             size_t num,
 118                             bool commit);
 119
 120 #endif /* RDMA_CORE_H */