xref: /xnu-8796.101.5/osfmk/kern/sync_sema.h (revision aca3beaa3dfbd42498b42c5e5ce20a938e6554e5)
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28 /*
29  * @OSF_COPYRIGHT@
30  *
31  */
32 /*
33  *	File:	kern/sync_sema.h
34  *	Author:	Joseph CaraDonna
35  *
36  *	Contains RT distributed semaphore synchronization service definitions.
37  */
38 
39 #ifndef _KERN_SYNC_SEMA_H_
40 #define _KERN_SYNC_SEMA_H_
41 
42 #include <kern/kern_types.h>
43 #include <mach/sync_policy.h>
44 #include <mach/clock_types.h>
45 
46 #ifdef MACH_KERNEL_PRIVATE
47 
48 #include <kern/queue.h>
49 #include <kern/waitq.h>
50 #include <os/refcnt.h>
51 
52 typedef struct semaphore {
53 	queue_chain_t     task_link;  /* chain of semaphores owned by a task */
54 	struct waitq      waitq;      /* queue of blocked threads & lock     */
55 	task_t            owner;      /* task that owns semaphore            */
56 	ipc_port_t        port;       /* semaphore port                      */
57 	os_ref_atomic_t   ref_count;  /* reference count                     */
58 	int               count;      /* current count value                 */
59 } Semaphore;
60 
61 #define semaphore_lock(semaphore)   waitq_lock(&(semaphore)->waitq)
62 #define semaphore_unlock(semaphore) waitq_unlock(&(semaphore)->waitq)
63 
64 extern void semaphore_reference(
65 	semaphore_t semaphore);
66 
67 extern void semaphore_dereference(
68 	semaphore_t semaphore);
69 
70 #pragma GCC visibility push(hidden)
71 
72 extern void semaphore_destroy_all(
73 	task_t      task);
74 
75 extern semaphore_t convert_port_to_semaphore(
76 	ipc_port_t  port);
77 
78 extern ipc_port_t convert_semaphore_to_port(
79 	semaphore_t semaphore);
80 
81 extern kern_return_t port_name_to_semaphore(
82 	mach_port_name_t  name,
83 	semaphore_t       *semaphore);
84 
85 #pragma GCC visibility pop
86 #endif /* MACH_KERNEL_PRIVATE */
87 #if XNU_KERNEL_PRIVATE
88 #pragma GCC visibility push(hidden)
89 
90 #define SEMAPHORE_CONT_NULL ((semaphore_cont_t)NULL)
91 typedef void (*semaphore_cont_t)(kern_return_t);
92 
93 extern kern_return_t semaphore_signal_internal_trap(
94 	mach_port_name_t sema_name);
95 
96 extern kern_return_t semaphore_timedwait_signal_trap_internal(
97 	mach_port_name_t wait_name,
98 	mach_port_name_t signal_name,
99 	unsigned int     sec,
100 	clock_res_t      nsec,
101 	semaphore_cont_t);
102 
103 extern kern_return_t semaphore_timedwait_trap_internal(
104 	mach_port_name_t name,
105 	unsigned int     sec,
106 	clock_res_t      nsec,
107 	semaphore_cont_t);
108 
109 extern kern_return_t semaphore_wait_signal_trap_internal(
110 	mach_port_name_t wait_name,
111 	mach_port_name_t signal_name,
112 	semaphore_cont_t);
113 
114 extern kern_return_t semaphore_wait_trap_internal(
115 	mach_port_name_t name,
116 	semaphore_cont_t);
117 
118 #pragma GCC visibility pop
119 #endif /* XNU_KERNEL_PRIVATE */
120 #endif /* _KERN_SYNC_SEMA_H_ */
121