PageRenderTime 18ms CodeModel.GetById 8ms app.highlight 8ms RepoModel.GetById 1ms app.codeStats 0ms

/arch/um/kernel/tt/uaccess_user.c

https://bitbucket.org/evzijst/gittest
C | 98 lines | 66 code | 17 blank | 15 comment | 9 complexity | 61d28df9c4f03b06b043f3f8b8962d42 MD5 | raw file
 1/* 
 2 * Copyright (C) 2001 Chris Emerson (cemerson@chiark.greenend.org.uk)
 3 * Copyright (C) 2001 Jeff Dike (jdike@karaya.com)
 4 * Licensed under the GPL
 5 */
 6
 7#include <setjmp.h>
 8#include <string.h>
 9#include "user_util.h"
10#include "uml_uaccess.h"
11#include "task.h"
12#include "kern_util.h"
13
14int __do_copy_from_user(void *to, const void *from, int n,
15			void **fault_addr, void **fault_catcher)
16{
17	struct tt_regs save = TASK_REGS(get_current())->tt;
18	unsigned long fault;
19	int faulted;
20
21	fault = __do_user_copy(to, from, n, fault_addr, fault_catcher,
22			       __do_copy, &faulted);
23	TASK_REGS(get_current())->tt = save;
24
25	if(!faulted) return(0);
26	else return(n - (fault - (unsigned long) from));
27}
28
29static void __do_strncpy(void *dst, const void *src, int count)
30{
31	strncpy(dst, src, count);
32}	
33
34int __do_strncpy_from_user(char *dst, const char *src, unsigned long count,
35			   void **fault_addr, void **fault_catcher)
36{
37	struct tt_regs save = TASK_REGS(get_current())->tt;
38	unsigned long fault;
39	int faulted;
40
41	fault = __do_user_copy(dst, src, count, fault_addr, fault_catcher,
42			       __do_strncpy, &faulted);
43	TASK_REGS(get_current())->tt = save;
44
45	if(!faulted) return(strlen(dst));
46	else return(-1);
47}
48
49static void __do_clear(void *to, const void *from, int n)
50{
51	memset(to, 0, n);
52}	
53
54int __do_clear_user(void *mem, unsigned long len,
55		    void **fault_addr, void **fault_catcher)
56{
57	struct tt_regs save = TASK_REGS(get_current())->tt;
58	unsigned long fault;
59	int faulted;
60
61	fault = __do_user_copy(mem, NULL, len, fault_addr, fault_catcher,
62			       __do_clear, &faulted);
63	TASK_REGS(get_current())->tt = save;
64
65	if(!faulted) return(0);
66	else return(len - (fault - (unsigned long) mem));
67}
68
69int __do_strnlen_user(const char *str, unsigned long n,
70		      void **fault_addr, void **fault_catcher)
71{
72	struct tt_regs save = TASK_REGS(get_current())->tt;
73	int ret;
74	unsigned long *faddrp = (unsigned long *)fault_addr;
75	sigjmp_buf jbuf;
76
77	*fault_catcher = &jbuf;
78	if(sigsetjmp(jbuf, 1) == 0)
79		ret = strlen(str) + 1;
80	else ret = *faddrp - (unsigned long) str;
81
82	*fault_addr = NULL;
83	*fault_catcher = NULL;
84
85	TASK_REGS(get_current())->tt = save;
86	return ret;
87}
88
89/*
90 * Overrides for Emacs so that we follow Linus's tabbing style.
91 * Emacs will notice this stuff at the end of the file and automatically
92 * adjust the settings for this buffer only.  This must remain at the end
93 * of the file.
94 * ---------------------------------------------------------------------------
95 * Local variables:
96 * c-file-style: "linux"
97 * End:
98 */