blob: 22a410b8003b78954f972523e98d341d30eefa27 [file] [log] [blame]
Bryan Wu1394f032007-05-06 14:50:22 -07001/* Changes made by Lineo Inc. May 2001
2 *
3 * Based on: include/asm-m68knommu/uaccess.h
4 */
5
6#ifndef __BLACKFIN_UACCESS_H
7#define __BLACKFIN_UACCESS_H
8
9/*
10 * User space memory access functions
11 */
12#include <linux/sched.h>
13#include <linux/mm.h>
14#include <linux/string.h>
15
16#include <asm/segment.h>
Sonic Zhangbde7db82007-05-21 18:09:34 +080017#ifdef CONFIG_ACCESS_CHECK
Bryan Wu1394f032007-05-06 14:50:22 -070018# include <asm/bfin-global.h>
19#endif
20
21#define get_ds() (KERNEL_DS)
22#define get_fs() (current_thread_info()->addr_limit)
23
24static inline void set_fs(mm_segment_t fs)
25{
26 current_thread_info()->addr_limit = fs;
27}
28
29#define segment_eq(a,b) ((a) == (b))
30
31#define VERIFY_READ 0
32#define VERIFY_WRITE 1
33
Bernd Schmidt3ca32c12007-12-24 12:40:29 +080034#define access_ok(type, addr, size) _access_ok((unsigned long)(addr), (size))
Bryan Wu1394f032007-05-06 14:50:22 -070035
36static inline int is_in_rom(unsigned long addr)
37{
38 /*
39 * What we are really trying to do is determine if addr is
40 * in an allocated kernel memory region. If not then assume
41 * we cannot free it or otherwise de-allocate it. Ideally
42 * we could restrict this to really being in a ROM or flash,
43 * but that would need to be done on a board by board basis,
44 * not globally.
45 */
46 if ((addr < _ramstart) || (addr >= _ramend))
47 return (1);
48
49 /* Default case, not in ROM */
50 return (0);
51}
52
53/*
54 * The fs value determines whether argument validity checking should be
55 * performed or not. If get_fs() == USER_DS, checking is performed, with
56 * get_fs() == KERNEL_DS, checking is bypassed.
57 */
58
Sonic Zhangbde7db82007-05-21 18:09:34 +080059#ifndef CONFIG_ACCESS_CHECK
Bryan Wu1394f032007-05-06 14:50:22 -070060static inline int _access_ok(unsigned long addr, unsigned long size) { return 1; }
61#else
62#ifdef CONFIG_ACCESS_OK_L1
63extern int _access_ok(unsigned long addr, unsigned long size)__attribute__((l1_text));
64#else
65extern int _access_ok(unsigned long addr, unsigned long size);
66#endif
67#endif
68
69/*
70 * The exception table consists of pairs of addresses: the first is the
71 * address of an instruction that is allowed to fault, and the second is
72 * the address at which the program should continue. No registers are
73 * modified, so it is entirely up to the continuation code to figure out
74 * what to do.
75 *
76 * All the routines below use bits of fixup code that are out of line
77 * with the main instruction path. This means when everything is well,
78 * we don't even have to jump over them. Further, they do not intrude
79 * on our cache or tlb entries.
80 */
81
82struct exception_table_entry {
83 unsigned long insn, fixup;
84};
85
86/* Returns 0 if exception not found and fixup otherwise. */
87extern unsigned long search_exception_table(unsigned long);
88
89/*
90 * These are the main single-value transfer routines. They automatically
91 * use the right size if we just have the right pointer type.
92 */
93
94#define put_user(x,p) \
95 ({ \
96 int _err = 0; \
97 typeof(*(p)) _x = (x); \
98 typeof(*(p)) *_p = (p); \
99 if (!access_ok(VERIFY_WRITE, _p, sizeof(*(_p)))) {\
100 _err = -EFAULT; \
101 } \
102 else { \
103 switch (sizeof (*(_p))) { \
104 case 1: \
105 __put_user_asm(_x, _p, B); \
106 break; \
107 case 2: \
108 __put_user_asm(_x, _p, W); \
109 break; \
110 case 4: \
111 __put_user_asm(_x, _p, ); \
112 break; \
113 case 8: { \
114 long _xl, _xh; \
115 _xl = ((long *)&_x)[0]; \
116 _xh = ((long *)&_x)[1]; \
117 __put_user_asm(_xl, ((long *)_p)+0, ); \
118 __put_user_asm(_xh, ((long *)_p)+1, ); \
119 } break; \
120 default: \
121 _err = __put_user_bad(); \
122 break; \
123 } \
124 } \
125 _err; \
126 })
127
128#define __put_user(x,p) put_user(x,p)
129static inline int bad_user_access_length(void)
130{
131 panic("bad_user_access_length");
132 return -1;
133}
134
135#define __put_user_bad() (printk(KERN_INFO "put_user_bad %s:%d %s\n",\
136 __FILE__, __LINE__, __FUNCTION__),\
137 bad_user_access_length(), (-EFAULT))
138
139/*
140 * Tell gcc we read from memory instead of writing: this is because
141 * we do not write to any memory gcc knows about, so there are no
142 * aliasing issues.
143 */
144
145#define __ptr(x) ((unsigned long *)(x))
146
147#define __put_user_asm(x,p,bhw) \
148 __asm__ (#bhw"[%1] = %0;\n\t" \
149 : /* no outputs */ \
150 :"d" (x),"a" (__ptr(p)) : "memory")
151
152#define get_user(x,p) \
153 ({ \
154 int _err = 0; \
155 typeof(*(p)) *_p = (p); \
156 if (!access_ok(VERIFY_READ, _p, sizeof(*(_p)))) { \
157 _err = -EFAULT; \
158 } \
159 else { \
160 switch (sizeof(*(_p))) { \
161 case 1: \
162 __get_user_asm(x, _p, B,(Z)); \
163 break; \
164 case 2: \
165 __get_user_asm(x, _p, W,(Z)); \
166 break; \
167 case 4: \
168 __get_user_asm(x, _p, , ); \
169 break; \
170 case 8: { \
171 unsigned long _xl, _xh; \
172 __get_user_asm(_xl, ((unsigned long *)_p)+0, , ); \
173 __get_user_asm(_xh, ((unsigned long *)_p)+1, , ); \
174 ((unsigned long *)&x)[0] = _xl; \
175 ((unsigned long *)&x)[1] = _xh; \
176 } break; \
177 default: \
178 x = 0; \
179 printk(KERN_INFO "get_user_bad: %s:%d %s\n", \
180 __FILE__, __LINE__, __FUNCTION__); \
181 _err = __get_user_bad(); \
182 break; \
183 } \
184 } \
185 _err; \
186 })
187
188#define __get_user(x,p) get_user(x,p)
189
190#define __get_user_bad() (bad_user_access_length(), (-EFAULT))
191
192#define __get_user_asm(x,p,bhw,option) \
193 { \
194 unsigned long _tmp; \
195 __asm__ ("%0 =" #bhw "[%1]"#option";\n\t" \
196 : "=d" (_tmp) \
197 : "a" (__ptr(p))); \
198 (x) = (__typeof__(*(p))) _tmp; \
199 }
200
201#define __copy_from_user(to, from, n) copy_from_user(to, from, n)
202#define __copy_to_user(to, from, n) copy_to_user(to, from, n)
203#define __copy_to_user_inatomic __copy_to_user
204#define __copy_from_user_inatomic __copy_from_user
205
206#define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n))\
207 return retval; })
208
209#define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n))\
210 return retval; })
211
212static inline long copy_from_user(void *to,
213 const void __user * from, unsigned long n)
214{
215 if (access_ok(VERIFY_READ, from, n))
216 memcpy(to, from, n);
217 else
218 return n;
219 return 0;
220}
221
222static inline long copy_to_user(void *to,
223 const void __user * from, unsigned long n)
224{
225 if (access_ok(VERIFY_WRITE, to, n))
226 memcpy(to, from, n);
227 else
228 return n;
229 return 0;
230}
231
232/*
233 * Copy a null terminated string from userspace.
234 */
235
236static inline long strncpy_from_user(char *dst,
237 const char *src, long count)
238{
239 char *tmp;
240 if (!access_ok(VERIFY_READ, src, 1))
241 return -EFAULT;
242 strncpy(dst, src, count);
243 for (tmp = dst; *tmp && count > 0; tmp++, count--) ;
244 return (tmp - dst);
245}
246
247/*
248 * Return the size of a string (including the ending 0)
249 *
250 * Return 0 on exception, a value greater than N if too long
251 */
252static inline long strnlen_user(const char *src, long n)
253{
254 return (strlen(src) + 1);
255}
256
257#define strlen_user(str) strnlen_user(str, 32767)
258
259/*
260 * Zero Userspace
261 */
262
263static inline unsigned long __clear_user(void *to, unsigned long n)
264{
265 memset(to, 0, n);
266 return 0;
267}
268
269#define clear_user(to, n) __clear_user(to, n)
270
271#endif /* _BLACKFIN_UACCESS_H */