xref: /linux/arch/um/include/shared/skas/stub-data.h (revision 76ed9158e1d474e963fc59da7a461b27a2212c5a)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 
4  * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
5  * Copyright (C) 2005 Jeff Dike (jdike@karaya.com)
6  */
7 
8 #ifndef __STUB_DATA_H
9 #define __STUB_DATA_H
10 
11 #include <linux/compiler_types.h>
12 #include <as-layout.h>
13 #include <sysdep/tls.h>
14 
15 #define STUB_NEXT_SYSCALL(s) \
16 	((struct stub_syscall *) (((unsigned long) s) + (s)->cmd_len))
17 
18 enum stub_syscall_type {
19 	STUB_SYSCALL_UNSET = 0,
20 	STUB_SYSCALL_MMAP,
21 	STUB_SYSCALL_MUNMAP,
22 	STUB_SYSCALL_MPROTECT,
23 	STUB_SYSCALL_LDT,
24 };
25 
26 struct stub_syscall {
27 	union {
28 		struct {
29 			unsigned long addr;
30 			unsigned long length;
31 			unsigned long offset;
32 			int fd;
33 			int prot;
34 		} mem;
35 		struct {
36 			user_desc_t desc;
37 			int func;
38 		} ldt;
39 	};
40 
41 	enum stub_syscall_type syscall;
42 };
43 
44 struct stub_data {
45 	unsigned long offset;
46 	int fd;
47 	long err, child_err;
48 
49 	int syscall_data_len;
50 	/* 128 leaves enough room for additional fields in the struct */
51 	struct stub_syscall syscall_data[(UM_KERN_PAGE_SIZE - 128) / sizeof(struct stub_syscall)] __aligned(16);
52 
53 	/* Stack for our signal handlers and for calling into . */
54 	unsigned char sigstack[UM_KERN_PAGE_SIZE] __aligned(UM_KERN_PAGE_SIZE);
55 };
56 
57 #endif
58