xref: /linux/drivers/md/dm-vdo/completion.h (revision 906fd46a65383cd639e5eec72a047efc33045d86)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright 2023 Red Hat
4  */
5 
6 #ifndef VDO_COMPLETION_H
7 #define VDO_COMPLETION_H
8 
9 #include "permassert.h"
10 
11 #include "status-codes.h"
12 #include "types.h"
13 
14 /**
15  * vdo_run_completion() - Run a completion's callback or error handler on the current thread.
16  *
17  * Context: This function must be called from the correct callback thread.
18  */
19 static inline void vdo_run_completion(struct vdo_completion *completion)
20 {
21 	if ((completion->result != VDO_SUCCESS) && (completion->error_handler != NULL)) {
22 		completion->error_handler(completion);
23 		return;
24 	}
25 
26 	completion->callback(completion);
27 }
28 
29 void vdo_set_completion_result(struct vdo_completion *completion, int result);
30 
31 void vdo_initialize_completion(struct vdo_completion *completion, struct vdo *vdo,
32 			       enum vdo_completion_type type);
33 
34 /**
35  * vdo_reset_completion() - Reset a completion to a clean state, while keeping the type, vdo and
36  *                          parent information.
37  */
38 static inline void vdo_reset_completion(struct vdo_completion *completion)
39 {
40 	completion->result = VDO_SUCCESS;
41 	completion->complete = false;
42 }
43 
44 void vdo_launch_completion_with_priority(struct vdo_completion *completion,
45 					 enum vdo_completion_priority priority);
46 
47 /**
48  * vdo_launch_completion() - Launch a completion with default priority.
49  */
50 static inline void vdo_launch_completion(struct vdo_completion *completion)
51 {
52 	vdo_launch_completion_with_priority(completion, VDO_WORK_Q_DEFAULT_PRIORITY);
53 }
54 
55 /**
56  * vdo_continue_completion() - Continue processing a completion.
57  * @result: The current result (will not mask older errors).
58  *
59  * Continue processing a completion by setting the current result and calling
60  * vdo_launch_completion().
61  */
62 static inline void vdo_continue_completion(struct vdo_completion *completion, int result)
63 {
64 	vdo_set_completion_result(completion, result);
65 	vdo_launch_completion(completion);
66 }
67 
68 void vdo_finish_completion(struct vdo_completion *completion);
69 
70 /**
71  * vdo_fail_completion() - Set the result of a completion if it does not already have an error,
72  *                         then finish it.
73  */
74 static inline void vdo_fail_completion(struct vdo_completion *completion, int result)
75 {
76 	vdo_set_completion_result(completion, result);
77 	vdo_finish_completion(completion);
78 }
79 
80 /**
81  * vdo_assert_completion_type() - Assert that a completion is of the correct type.
82  *
83  * Return: VDO_SUCCESS or an error
84  */
85 static inline int vdo_assert_completion_type(struct vdo_completion *completion,
86 					     enum vdo_completion_type expected)
87 {
88 	return VDO_ASSERT(expected == completion->type,
89 			  "completion type should be %u, not %u", expected,
90 			  completion->type);
91 }
92 
93 static inline void vdo_set_completion_callback(struct vdo_completion *completion,
94 					       vdo_action_fn callback,
95 					       thread_id_t callback_thread_id)
96 {
97 	completion->callback = callback;
98 	completion->callback_thread_id = callback_thread_id;
99 }
100 
101 /**
102  * vdo_launch_completion_callback() - Set the callback for a completion and launch it immediately.
103  */
104 static inline void vdo_launch_completion_callback(struct vdo_completion *completion,
105 						  vdo_action_fn callback,
106 						  thread_id_t callback_thread_id)
107 {
108 	vdo_set_completion_callback(completion, callback, callback_thread_id);
109 	vdo_launch_completion(completion);
110 }
111 
112 /**
113  * vdo_prepare_completion() - Prepare a completion for launch.
114  *
115  * Resets the completion, and then sets its callback, error handler, callback thread, and parent.
116  */
117 static inline void vdo_prepare_completion(struct vdo_completion *completion,
118 					  vdo_action_fn callback,
119 					  vdo_action_fn error_handler,
120 					  thread_id_t callback_thread_id, void *parent)
121 {
122 	vdo_reset_completion(completion);
123 	vdo_set_completion_callback(completion, callback, callback_thread_id);
124 	completion->error_handler = error_handler;
125 	completion->parent = parent;
126 }
127 
128 /**
129  * vdo_prepare_completion_for_requeue() - Prepare a completion for launch ensuring that it will
130  *                                        always be requeued.
131  *
132  * Resets the completion, and then sets its callback, error handler, callback thread, and parent.
133  */
134 static inline void vdo_prepare_completion_for_requeue(struct vdo_completion *completion,
135 						      vdo_action_fn callback,
136 						      vdo_action_fn error_handler,
137 						      thread_id_t callback_thread_id,
138 						      void *parent)
139 {
140 	vdo_prepare_completion(completion, callback, error_handler,
141 			       callback_thread_id, parent);
142 	completion->requeue = true;
143 }
144 
145 void vdo_enqueue_completion(struct vdo_completion *completion,
146 			    enum vdo_completion_priority priority);
147 
148 
149 bool vdo_requeue_completion_if_needed(struct vdo_completion *completion,
150 				      thread_id_t callback_thread_id);
151 
152 #endif /* VDO_COMPLETION_H */
153