xref: /xnu-11417.140.69/osfmk/kern/smr_types.h (revision 43a90889846e00bfb5cf1d255cdc0a701a1e05a4)
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28 
29 #ifndef _KERN_SMR_TYPES_H_
30 #define _KERN_SMR_TYPES_H_
31 
32 #include <sys/cdefs.h>
33 #include <stdbool.h>
34 #include <stdint.h>
35 #include <os/base.h>
36 
37 __BEGIN_DECLS
38 
39 /*!
40  * @typedef smr_seq_t
41  *
42  * @brief
43  * Represents an opaque SMR sequence number.
44  */
45 typedef unsigned long           smr_seq_t;
46 
47 /*!
48  * @typedef smr_t
49  *
50  * @brief
51  * Type for an SMR domain.
52  */
53 typedef struct smr             *smr_t;
54 
55 
56 /*!
57  * @typedef smr_node_t
58  *
59  * @brief
60  * Intrusive data structure used with @c ssmr_call() to defer callbacks
61  * to a safe time.
62  */
63 typedef struct smr_node        *smr_node_t;
64 
65 /*!
66  * @typedef smr_cb_t
67  *
68  * @brief
69  * A callback acting on an @c smr_node_t to destroy it.
70  */
71 typedef void (*smr_cb_t)(smr_node_t);
72 
73 struct smr_node {
74 	struct smr_node        *smrn_next;
75 	smr_cb_t XNU_PTRAUTH_SIGNED_FUNCTION_PTR("ssmr_cb_t") smrn_cb;
76 };
77 
78 /*!
79  * @macro SMR_POINTER_DECL
80  *
81  * @brief
82  * Macro to declare a pointer type that uses SMR for access.
83  */
84 #define SMR_POINTER_DECL(name, type_t) \
85 	struct name { type_t volatile __smr_ptr; }
86 
87 /*!
88  * @macro SMR_POINTER
89  *
90  * @brief
91  * Macro to declare a pointer that uses SMR for access.
92  */
93 #define SMR_POINTER(type_t) \
94 	SMR_POINTER_DECL(, type_t)
95 
96 
97 /* internal types that clients should not use directly */
98 typedef SMR_POINTER(struct smrq_slink *) __smrq_slink_t;
99 typedef SMR_POINTER(struct smrq_link *)  __smrq_link_t;
100 
101 
102 /*!
103  * @struct smrq_slink
104  *
105  * @brief
106  * Type used to represent a linkage in an SMR queue
107  * (single form, with O(n) deletion).
108  */
109 struct smrq_slink {
110 	__smrq_slink_t          next;
111 };
112 
113 /*!
114  * @struct smrq_link
115  *
116  * @brief
117  * Type used to represent a linkage in an SMR queue
118  * (double form, with O(1) deletion).
119  */
120 struct smrq_link {
121 	__smrq_link_t           next;
122 	__smrq_link_t          *prev;
123 };
124 
125 
126 /*!
127  * @struct smrq_slist_head
128  *
129  * @brief
130  * Type used to represent the head of a singly linked list.
131  *
132  * @discussion
133  * This must be used with @c smrq_slink linkages.
134  *
135  * This type supports:
136  * - insertion at the head,
137  * - O(n) removal / replacement.
138  */
139 struct smrq_slist_head {
140 	__smrq_slink_t          first;
141 };
142 
143 #define SMRQ_SLIST_INITIALIZER(name) \
144 	{ .first = { NULL } }
145 
146 /*!
147  * @struct smrq_list_head
148  *
149  * @brief
150  * Type used to represent the head of a doubly linked list.
151  *
152  * @discussion
153  * This must be used with @c smrq_link linkages.
154  *
155  * This type supports:
156  * - insertion at the head,
157  * - O(1) removal / replacement.
158  */
159 struct smrq_list_head {
160 	__smrq_link_t           first;
161 };
162 
163 #define SMRQ_LIST_INITIALIZER(name) \
164 	{ .first = { NULL } }
165 
166 /*!
167  * @struct smrq_stailq_head
168  *
169  * @brief
170  * Type used to represent the head of a singly linked tail-queue.
171  *
172  * @discussion
173  * This must be used with @c smrq_slink linkages.
174  *
175  * This type supports:
176  * - insertion at the head,
177  * - insertion at the tail,
178  * - O(n) removal / replacement.
179  */
180 struct smrq_stailq_head {
181 	__smrq_slink_t          first;
182 	__smrq_slink_t         *last;
183 };
184 
185 #define SMRQ_STAILQ_INITIALIZER(name) \
186 	{ .first = { NULL }, .last = &(name).first }
187 
188 /*!
189  * @struct smrq_tailq_head
190  *
191  * @brief
192  * Type used to represent the head of a doubly linked tail-queue.
193  *
194  * @discussion
195  * This must be used with @c smrq_link linkages.
196  *
197  * This type supports:
198  * - insertion at the head,
199  * - insertion at the tail,
200  * - O(1) removal / replacement.
201  */
202 struct smrq_tailq_head {
203 	__smrq_link_t           first;
204 	__smrq_link_t          *last;
205 };
206 
207 #define SMRQ_TAILQ_INITIALIZER(name) \
208 	{ .first = { NULL }, .last = &(name).first }
209 
210 __END_DECLS
211 
212 #endif /* _KERN_SMR_TYPES_H_ */
213