xref: /freebsd/sys/sys/sysent.h (revision 8ab2f5ecc596131f6ca790d6ae35540c06ed7985)
1 /*-
2  * Copyright (c) 1982, 1988, 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #ifndef _SYS_SYSENT_H_
33 #define	_SYS_SYSENT_H_
34 
35 struct thread;
36 
37 typedef	int	sy_call_t(struct thread *, void *);
38 
39 struct sysent {		/* system call table */
40 	int	sy_narg;	/* number of arguments */
41 	sy_call_t *sy_call;	/* implementing function */
42 };
43 
44 #define SYF_ARGMASK	0x0000FFFF
45 #define SYF_MPSAFE	0x00010000
46 
47 struct image_params;
48 struct __sigset;
49 struct trapframe;
50 struct vnode;
51 
52 struct sysentvec {
53 	int		sv_size;	/* number of entries */
54 	struct sysent	*sv_table;	/* pointer to sysent */
55 	u_int		sv_mask;	/* optional mask to index */
56 	int		sv_sigsize;	/* size of signal translation table */
57 	int		*sv_sigtbl;	/* signal translation table */
58 	int		sv_errsize;	/* size of errno translation table */
59 	int 		*sv_errtbl;	/* errno translation table */
60 	int		(*sv_transtrap)(int, int);
61 					/* translate trap-to-signal mapping */
62 	int		(*sv_fixup)(register_t **, struct image_params *);
63 					/* stack fixup function */
64 	void		(*sv_sendsig)(void (*)(int), int, struct __sigset *,
65 			    u_long);	/* send signal */
66 	char 		*sv_sigcode;	/* start of sigtramp code */
67 	int 		*sv_szsigcode;	/* size of sigtramp code */
68 	void		(*sv_prepsyscall)(struct trapframe *, int *, u_int *,
69 			    caddr_t *);
70 	char		*sv_name;	/* name of binary type */
71 	int		(*sv_coredump)(struct thread *, struct vnode *, off_t);
72 					/* function to dump core, or NULL */
73 	int		(*sv_imgact_try)(struct image_params *);
74 	int		sv_minsigstksz;	/* minimum signal stack size */
75 	int		sv_pagesize;	/* pagesize */
76 	vm_offset_t	sv_minuser;	/* VM_MIN_ADDRESS */
77 	vm_offset_t	sv_maxuser;	/* VM_MAXUSER_ADDRESS */
78 	vm_offset_t	sv_usrstack;	/* USRSTACK */
79 	vm_offset_t	sv_psstrings;	/* PS_STRINGS */
80 	int		sv_stackprot;	/* vm protection for stack */
81 	register_t	*(*sv_copyout_strings)(struct image_params *);
82 	void		(*sv_setregs)(struct thread *, u_long, u_long, u_long);
83 	void		(*sv_fixlimits)(struct image_params *);
84 };
85 
86 #ifdef _KERNEL
87 extern struct sysentvec aout_sysvec;
88 extern struct sysentvec elf_freebsd_sysvec;
89 extern struct sysentvec null_sysvec;
90 extern struct sysent sysent[];
91 
92 #define NO_SYSCALL (-1)
93 
94 struct module;
95 
96 struct syscall_module_data {
97        int     (*chainevh)(struct module *, int, void *); /* next handler */
98        void    *chainarg;      /* arg for next event handler */
99        int     *offset;         /* offset into sysent */
100        struct  sysent *new_sysent; /* new sysent */
101        struct  sysent old_sysent; /* old sysent */
102 };
103 
104 #define SYSCALL_MODULE(name, offset, new_sysent, evh, arg)     \
105 static struct syscall_module_data name##_syscall_mod = {       \
106        evh, arg, offset, new_sysent, { 0, NULL }               \
107 };                                                             \
108                                                                \
109 static moduledata_t name##_mod = {                             \
110        #name,                                                  \
111        syscall_module_handler,                                 \
112        &name##_syscall_mod                                     \
113 };                                                             \
114 DECLARE_MODULE(name, name##_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE)
115 
116 #define SYSCALL_MODULE_HELPER(syscallname)              \
117 static int syscallname##_syscall = SYS_##syscallname;   \
118 static struct sysent syscallname##_sysent = {           \
119     (sizeof(struct syscallname ## _args )               \
120      / sizeof(register_t)),                             \
121     (sy_call_t *)& syscallname                          \
122 };                                                      \
123 SYSCALL_MODULE(syscallname,                             \
124     & syscallname##_syscall, & syscallname##_sysent,    \
125     NULL, NULL);
126 
127 int    syscall_register(int *offset, struct sysent *new_sysent,
128 	    struct sysent *old_sysent);
129 int    syscall_deregister(int *offset, struct sysent *old_sysent);
130 int    syscall_module_handler(struct module *mod, int what, void *arg);
131 
132 #endif /* _KERNEL */
133 
134 #endif /* !_SYS_SYSENT_H_ */
135