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
 46int uverbs_ns_idx(u16 *id, unsigned int ns_count);
 47const struct uverbs_object_spec *uverbs_get_object(const struct ib_device *ibdev,
 48						   uint16_t object);
 49const 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 */
 58void uverbs_cleanup_ucontext(struct ib_ucontext *ucontext, bool device_removed);
 59void 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 */
 67void 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 */
 74void 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 */
 82void 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 */
 93struct 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);
 97int 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 */
115int 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 */