aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/include/rdma/uverbs_types.h
blob: ccd11631c167c07a617fcd2bcc71bb8bca6e5716 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
/*
 * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
 */

#ifndef _UVERBS_TYPES_
#define _UVERBS_TYPES_

#include <linux/kernel.h>
#include <rdma/ib_verbs.h>

struct uverbs_obj_type;
struct uverbs_api_object;

enum rdma_lookup_mode {
	UVERBS_LOOKUP_READ,
	UVERBS_LOOKUP_WRITE,
	/*
	 * Destroy is like LOOKUP_WRITE, except that the uobject is not
	 * locked.  uobj_destroy is used to convert a LOOKUP_DESTROY lock into
	 * a LOOKUP_WRITE lock.
	 */
	UVERBS_LOOKUP_DESTROY,
};

/*
 * The following sequences are valid:
 * Success flow:
 *   alloc_begin
 *   alloc_commit
 *    [..]
 * Access flow:
 *   lookup_get(exclusive=false) & uverbs_try_lock_object
 *   lookup_put(exclusive=false) via rdma_lookup_put_uobject
 * Destruction flow:
 *   lookup_get(exclusive=true) & uverbs_try_lock_object
 *   remove_commit
 *   remove_handle (optional)
 *   lookup_put(exclusive=true) via rdma_lookup_put_uobject
 *
 * Allocate Error flow #1
 *   alloc_begin
 *   alloc_abort
 * Allocate Error flow #2
 *   alloc_begin
 *   remove_commit
 *   alloc_abort
 * Allocate Error flow #3
 *   alloc_begin
 *   alloc_commit (fails)
 *   remove_commit
 *   alloc_abort
 *
 * In all cases the caller must hold the ufile kref until alloc_commit or
 * alloc_abort returns.
 */
struct uverbs_obj_type_class {
	struct ib_uobject *(*alloc_begin)(const struct uverbs_api_object *obj,
					  struct uverbs_attr_bundle *attrs);
	/* This consumes the kref on uobj */
	void (*alloc_commit)(struct ib_uobject *uobj);
	/* This does not consume the kref on uobj */
	void (*alloc_abort)(struct ib_uobject *uobj);

	struct ib_uobject *(*lookup_get)(const struct uverbs_api_object *obj,
					 struct ib_uverbs_file *ufile, s64 id,
					 enum rdma_lookup_mode mode);
	void (*lookup_put)(struct ib_uobject *uobj, enum rdma_lookup_mode mode);
	/* This does not consume the kref on uobj */
	int __must_check (*destroy_hw)(struct ib_uobject *uobj,
				       enum rdma_remove_reason why,
				       struct uverbs_attr_bundle *attrs);
	void (*remove_handle)(struct ib_uobject *uobj);
	void (*swap_uobjects)(struct ib_uobject *obj_old,
			      struct ib_uobject *obj_new);
};

struct uverbs_obj_type {
	const struct uverbs_obj_type_class * const type_class;
	size_t	     obj_size;
};

/*
 * Objects type classes which support a detach state (object is still alive but
 * it's not attached to any context need to make sure:
 * (a) no call through to a driver after a detach is called
 * (b) detach isn't called concurrently with context_cleanup
 */

struct uverbs_obj_idr_type {
	/*
	 * In idr based objects, uverbs_obj_type_class points to a generic
	 * idr operations. In order to specialize the underlying types (e.g. CQ,
	 * QPs, etc.), we add destroy_object specific callbacks.
	 */
	struct uverbs_obj_type  type;

	/* Free driver resources from the uobject, make the driver uncallable,
	 * and move the uobject to the detached state. If the object was
	 * destroyed by the user's request, a failure should leave the uobject
	 * completely unchanged.
	 */
	int __must_check (*destroy_object)(struct ib_uobject *uobj,
					   enum rdma_remove_reason why,
					   struct uverbs_attr_bundle *attrs);
};

struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_api_object *obj,
					   struct ib_uverbs_file *ufile, s64 id,
					   enum rdma_lookup_mode mode,
					   struct uverbs_attr_bundle *attrs);
void rdma_lookup_put_uobject(struct ib_uobject *uobj,
			     enum rdma_lookup_mode mode);
struct ib_uobject *rdma_alloc_begin_uobject(const struct uverbs_api_object *obj,
					    struct uverbs_attr_bundle *attrs);
void rdma_alloc_abort_uobject(struct ib_uobject *uobj,
			      struct uverbs_attr_bundle *attrs,
			      bool hw_obj_valid);
void rdma_alloc_commit_uobject(struct ib_uobject *uobj,
			       struct uverbs_attr_bundle *attrs);
void rdma_assign_uobject(struct ib_uobject *to_uobj,
			 struct ib_uobject *new_uobj,
			 struct uverbs_attr_bundle *attrs);

/*
 * uverbs_uobject_get is called in order to increase the reference count on
 * an uobject. This is useful when a handler wants to keep the uobject's memory
 * alive, regardless if this uobject is still alive in the context's objects
 * repository. Objects are put via uverbs_uobject_put.
 */
static inline void uverbs_uobject_get(struct ib_uobject *uobject)
{
	kref_get(&uobject->ref);
}
void uverbs_uobject_put(struct ib_uobject *uobject);

struct uverbs_obj_fd_type {
	/*
	 * In fd based objects, uverbs_obj_type_ops points to generic
	 * fd operations. In order to specialize the underlying types (e.g.
	 * completion_channel), we use fops, name and flags for fd creation.
	 * destroy_object is called when the uobject is to be destroyed,
	 * because the driver is removed or the FD is closed.
	 */
	struct uverbs_obj_type  type;
	void (*destroy_object)(struct ib_uobject *uobj,
			       enum rdma_remove_reason why);
	const struct file_operations	*fops;
	const char			*name;
	int				flags;
};

extern const struct uverbs_obj_type_class uverbs_idr_class;
extern const struct uverbs_obj_type_class uverbs_fd_class;
int uverbs_uobject_fd_release(struct inode *inode, struct file *filp);

#define UVERBS_BUILD_BUG_ON(cond) (sizeof(char[1 - 2 * !!(cond)]) -	\
				   sizeof(char))
#define UVERBS_TYPE_ALLOC_FD(_obj_size, _destroy_object, _fops, _name, _flags) \
	((&((const struct uverbs_obj_fd_type)				\
	 {.type = {							\
		.type_class = &uverbs_fd_class,				\
		.obj_size = (_obj_size) +				\
			UVERBS_BUILD_BUG_ON((_obj_size) <               \
					    sizeof(struct ib_uobject)), \
	 },								\
	 .destroy_object = _destroy_object,				\
	 .fops = _fops,							\
	 .name = _name,							\
	 .flags = _flags}))->type)
#define UVERBS_TYPE_ALLOC_IDR_SZ(_size, _destroy_object)	\
	((&((const struct uverbs_obj_idr_type)				\
	 {.type = {							\
		.type_class = &uverbs_idr_class,			\
		.obj_size = (_size) +					\
			UVERBS_BUILD_BUG_ON((_size) <			\
					    sizeof(struct ib_uobject))	\
	 },								\
	 .destroy_object = _destroy_object,}))->type)
#define UVERBS_TYPE_ALLOC_IDR(_destroy_object)			\
	 UVERBS_TYPE_ALLOC_IDR_SZ(sizeof(struct ib_uobject),	\
				  _destroy_object)

#endif