1 /*
2 * Copyright (c) 2017, Mellanox Technologies inc. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33 #ifndef _UVERBS_TYPES_
34 #define _UVERBS_TYPES_
35
36 #include <linux/kernel.h>
37 #include <linux/fs.h>
38 #include <rdma/ib_verbs.h>
39
40 struct uverbs_obj_type;
41 struct uverbs_api_object;
42 struct uverbs_attr_bundle;
43 struct ib_uverbs_file;
44
45 enum rdma_remove_reason;
46
47 enum rdma_lookup_mode {
48 UVERBS_LOOKUP_READ,
49 UVERBS_LOOKUP_WRITE,
50 /*
51 * Destroy is like LOOKUP_WRITE, except that the uobject is not
52 * locked. uobj_destroy is used to convert a LOOKUP_DESTROY lock into
53 * a LOOKUP_WRITE lock.
54 */
55 UVERBS_LOOKUP_DESTROY,
56 };
57
58 /*
59 * The following sequences are valid:
60 * Success flow:
61 * alloc_begin
62 * alloc_commit
63 * [..]
64 * Access flow:
65 * lookup_get(exclusive=false) & uverbs_try_lock_object
66 * lookup_put(exclusive=false) via rdma_lookup_put_uobject
67 * Destruction flow:
68 * lookup_get(exclusive=true) & uverbs_try_lock_object
69 * remove_commit
70 * remove_handle (optional)
71 * lookup_put(exclusive=true) via rdma_lookup_put_uobject
72 *
73 * Allocate Error flow #1
74 * alloc_begin
75 * alloc_abort
76 * Allocate Error flow #2
77 * alloc_begin
78 * remove_commit
79 * alloc_abort
80 * Allocate Error flow #3
81 * alloc_begin
82 * alloc_commit (fails)
83 * remove_commit
84 * alloc_abort
85 *
86 * In all cases the caller must hold the ufile kref until alloc_commit or
87 * alloc_abort returns.
88 */
89 struct uverbs_obj_type_class {
90 struct ib_uobject *(*alloc_begin)(const struct uverbs_api_object *obj,
91 struct uverbs_attr_bundle *attrs);
92 /* This consumes the kref on uobj */
93 void (*alloc_commit)(struct ib_uobject *uobj);
94 /* This does not consume the kref on uobj */
95 void (*alloc_abort)(struct ib_uobject *uobj);
96
97 struct ib_uobject *(*lookup_get)(const struct uverbs_api_object *obj,
98 struct ib_uverbs_file *ufile, s64 id,
99 enum rdma_lookup_mode mode);
100 void (*lookup_put)(struct ib_uobject *uobj, enum rdma_lookup_mode mode);
101 /* This does not consume the kref on uobj */
102 int __must_check (*destroy_hw)(struct ib_uobject *uobj,
103 enum rdma_remove_reason why,
104 struct uverbs_attr_bundle *attrs);
105 void (*remove_handle)(struct ib_uobject *uobj);
106 };
107
108 struct uverbs_obj_type {
109 const struct uverbs_obj_type_class * const type_class;
110 size_t obj_size;
111 };
112
113 /*
114 * Objects type classes which support a detach state (object is still alive but
115 * it's not attached to any context need to make sure:
116 * (a) no call through to a driver after a detach is called
117 * (b) detach isn't called concurrently with context_cleanup
118 */
119
120 struct uverbs_obj_idr_type {
121 /*
122 * In idr based objects, uverbs_obj_type_class points to a generic
123 * idr operations. In order to specialize the underlying types (e.g. CQ,
124 * QPs, etc.), we add destroy_object specific callbacks.
125 */
126 struct uverbs_obj_type type;
127
128 /* Free driver resources from the uobject, make the driver uncallable,
129 * and move the uobject to the detached state. If the object was
130 * destroyed by the user's request, a failure should leave the uobject
131 * completely unchanged.
132 */
133 int __must_check (*destroy_object)(struct ib_uobject *uobj,
134 enum rdma_remove_reason why,
135 struct uverbs_attr_bundle *attrs);
136 };
137
138 struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_api_object *obj,
139 struct ib_uverbs_file *ufile, s64 id,
140 enum rdma_lookup_mode mode,
141 struct uverbs_attr_bundle *attrs);
142 void rdma_lookup_put_uobject(struct ib_uobject *uobj,
143 enum rdma_lookup_mode mode);
144 struct ib_uobject *rdma_alloc_begin_uobject(const struct uverbs_api_object *obj,
145 struct uverbs_attr_bundle *attrs);
146 void rdma_alloc_abort_uobject(struct ib_uobject *uobj,
147 struct uverbs_attr_bundle *attrs);
148 void rdma_alloc_commit_uobject(struct ib_uobject *uobj,
149 struct uverbs_attr_bundle *attrs);
150
151 /*
152 * uverbs_uobject_get is called in order to increase the reference count on
153 * an uobject. This is useful when a handler wants to keep the uobject's memory
154 * alive, regardless if this uobject is still alive in the context's objects
155 * repository. Objects are put via uverbs_uobject_put.
156 */
uverbs_uobject_get(struct ib_uobject * uobject)157 static inline void uverbs_uobject_get(struct ib_uobject *uobject)
158 {
159 kref_get(&uobject->ref);
160 }
161 void uverbs_uobject_put(struct ib_uobject *uobject);
162
163 struct uverbs_obj_fd_type {
164 /*
165 * In fd based objects, uverbs_obj_type_ops points to generic
166 * fd operations. In order to specialize the underlying types (e.g.
167 * completion_channel), we use fops, name and flags for fd creation.
168 * destroy_object is called when the uobject is to be destroyed,
169 * because the driver is removed or the FD is closed.
170 */
171 struct uverbs_obj_type type;
172 int (*destroy_object)(struct ib_uobject *uobj,
173 enum rdma_remove_reason why);
174 const struct file_operations *fops;
175 const char *name;
176 int flags;
177 };
178
179 extern const struct uverbs_obj_type_class uverbs_idr_class;
180 extern const struct uverbs_obj_type_class uverbs_fd_class;
181 int uverbs_uobject_fd_release(struct inode *inode, struct file *filp);
182
183 #define UVERBS_BUILD_BUG_ON(cond) (sizeof(char[1 - 2 * !!(cond)]) - \
184 sizeof(char))
185 #define UVERBS_TYPE_ALLOC_FD(_obj_size, _destroy_object, _fops, _name, _flags) \
186 ((&((const struct uverbs_obj_fd_type) \
187 {.type = { \
188 .type_class = &uverbs_fd_class, \
189 .obj_size = (_obj_size) + \
190 UVERBS_BUILD_BUG_ON((_obj_size) < \
191 sizeof(struct ib_uobject)), \
192 }, \
193 .destroy_object = _destroy_object, \
194 .fops = _fops, \
195 .name = _name, \
196 .flags = _flags}))->type)
197 #define UVERBS_TYPE_ALLOC_IDR_SZ(_size, _destroy_object) \
198 ((&((const struct uverbs_obj_idr_type) \
199 {.type = { \
200 .type_class = &uverbs_idr_class, \
201 .obj_size = (_size) + \
202 UVERBS_BUILD_BUG_ON((_size) < \
203 sizeof(struct ib_uobject)) \
204 }, \
205 .destroy_object = _destroy_object,}))->type)
206 #define UVERBS_TYPE_ALLOC_IDR(_destroy_object) \
207 UVERBS_TYPE_ALLOC_IDR_SZ(sizeof(struct ib_uobject), \
208 _destroy_object)
209
210 #endif
211