sparc: use the new generic strnlen_user() function
[~shefty/rdma-dev.git] / arch / sparc / include / asm / uaccess_64.h
1 #ifndef _ASM_UACCESS_H
2 #define _ASM_UACCESS_H
3
4 /*
5  * User space memory access functions
6  */
7
8 #ifdef __KERNEL__
9 #include <linux/errno.h>
10 #include <linux/compiler.h>
11 #include <linux/string.h>
12 #include <linux/thread_info.h>
13 #include <asm/asi.h>
14 #include <asm/spitfire.h>
15 #include <asm-generic/uaccess-unaligned.h>
16 #endif
17
18 #ifndef __ASSEMBLY__
19
20 #include <asm/processor.h>
21
22 /*
23  * Sparc64 is segmented, though more like the M68K than the I386.
24  * We use the secondary ASI to address user memory, which references a
25  * completely different VM map, thus there is zero chance of the user
26  * doing something queer and tricking us into poking kernel memory.
27  *
28  * What is left here is basically what is needed for the other parts of
29  * the kernel that expect to be able to manipulate, erum, "segments".
30  * Or perhaps more properly, permissions.
31  *
32  * "For historical reasons, these macros are grossly misnamed." -Linus
33  */
34
35 #define KERNEL_DS   ((mm_segment_t) { ASI_P })
36 #define USER_DS     ((mm_segment_t) { ASI_AIUS })       /* har har har */
37
38 #define VERIFY_READ     0
39 #define VERIFY_WRITE    1
40
41 #define get_fs() ((mm_segment_t) { get_thread_current_ds() })
42 #define get_ds() (KERNEL_DS)
43
44 #define segment_eq(a,b)  ((a).seg == (b).seg)
45
46 #define set_fs(val)                                                             \
47 do {                                                                            \
48         set_thread_current_ds((val).seg);                                       \
49         __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg));        \
50 } while(0)
51
52 static inline int __access_ok(const void __user * addr, unsigned long size)
53 {
54         return 1;
55 }
56
57 static inline int access_ok(int type, const void __user * addr, unsigned long size)
58 {
59         return 1;
60 }
61
62 /*
63  * The exception table consists of pairs of addresses: the first is the
64  * address of an instruction that is allowed to fault, and the second is
65  * the address at which the program should continue.  No registers are
66  * modified, so it is entirely up to the continuation code to figure out
67  * what to do.
68  *
69  * All the routines below use bits of fixup code that are out of line
70  * with the main instruction path.  This means when everything is well,
71  * we don't even have to jump over them.  Further, they do not intrude
72  * on our cache or tlb entries.
73  */
74
75 struct exception_table_entry {
76         unsigned int insn, fixup;
77 };
78
79 extern void __ret_efault(void);
80 extern void __retl_efault(void);
81
82 /* Uh, these should become the main single-value transfer routines..
83  * They automatically use the right size if we just have the right
84  * pointer type..
85  *
86  * This gets kind of ugly. We want to return _two_ values in "get_user()"
87  * and yet we don't want to do any pointers, because that is too much
88  * of a performance impact. Thus we have a few rather ugly macros here,
89  * and hide all the ugliness from the user.
90  */
91 #define put_user(x,ptr) ({ \
92 unsigned long __pu_addr = (unsigned long)(ptr); \
93 __chk_user_ptr(ptr); \
94 __put_user_nocheck((__typeof__(*(ptr)))(x),__pu_addr,sizeof(*(ptr))); })
95
96 #define get_user(x,ptr) ({ \
97 unsigned long __gu_addr = (unsigned long)(ptr); \
98 __chk_user_ptr(ptr); \
99 __get_user_nocheck((x),__gu_addr,sizeof(*(ptr)),__typeof__(*(ptr))); })
100
101 #define __put_user(x,ptr) put_user(x,ptr)
102 #define __get_user(x,ptr) get_user(x,ptr)
103
104 struct __large_struct { unsigned long buf[100]; };
105 #define __m(x) ((struct __large_struct *)(x))
106
107 #define __put_user_nocheck(data,addr,size) ({ \
108 register int __pu_ret; \
109 switch (size) { \
110 case 1: __put_user_asm(data,b,addr,__pu_ret); break; \
111 case 2: __put_user_asm(data,h,addr,__pu_ret); break; \
112 case 4: __put_user_asm(data,w,addr,__pu_ret); break; \
113 case 8: __put_user_asm(data,x,addr,__pu_ret); break; \
114 default: __pu_ret = __put_user_bad(); break; \
115 } __pu_ret; })
116
117 #define __put_user_asm(x,size,addr,ret)                                 \
118 __asm__ __volatile__(                                                   \
119         "/* Put user asm, inline. */\n"                                 \
120 "1:\t"  "st"#size "a %1, [%2] %%asi\n\t"                                \
121         "clr    %0\n"                                                   \
122 "2:\n\n\t"                                                              \
123         ".section .fixup,#alloc,#execinstr\n\t"                         \
124         ".align 4\n"                                                    \
125 "3:\n\t"                                                                \
126         "sethi  %%hi(2b), %0\n\t"                                       \
127         "jmpl   %0 + %%lo(2b), %%g0\n\t"                                \
128         " mov   %3, %0\n\n\t"                                           \
129         ".previous\n\t"                                                 \
130         ".section __ex_table,\"a\"\n\t"                                 \
131         ".align 4\n\t"                                                  \
132         ".word  1b, 3b\n\t"                                             \
133         ".previous\n\n\t"                                               \
134        : "=r" (ret) : "r" (x), "r" (__m(addr)),                         \
135          "i" (-EFAULT))
136
137 extern int __put_user_bad(void);
138
139 #define __get_user_nocheck(data,addr,size,type) ({ \
140 register int __gu_ret; \
141 register unsigned long __gu_val; \
142 switch (size) { \
143 case 1: __get_user_asm(__gu_val,ub,addr,__gu_ret); break; \
144 case 2: __get_user_asm(__gu_val,uh,addr,__gu_ret); break; \
145 case 4: __get_user_asm(__gu_val,uw,addr,__gu_ret); break; \
146 case 8: __get_user_asm(__gu_val,x,addr,__gu_ret); break; \
147 default: __gu_val = 0; __gu_ret = __get_user_bad(); break; \
148 } data = (type) __gu_val; __gu_ret; })
149
150 #define __get_user_nocheck_ret(data,addr,size,type,retval) ({ \
151 register unsigned long __gu_val __asm__ ("l1"); \
152 switch (size) { \
153 case 1: __get_user_asm_ret(__gu_val,ub,addr,retval); break; \
154 case 2: __get_user_asm_ret(__gu_val,uh,addr,retval); break; \
155 case 4: __get_user_asm_ret(__gu_val,uw,addr,retval); break; \
156 case 8: __get_user_asm_ret(__gu_val,x,addr,retval); break; \
157 default: if (__get_user_bad()) return retval; \
158 } data = (type) __gu_val; })
159
160 #define __get_user_asm(x,size,addr,ret)                                 \
161 __asm__ __volatile__(                                                   \
162         "/* Get user asm, inline. */\n"                                 \
163 "1:\t"  "ld"#size "a [%2] %%asi, %1\n\t"                                \
164         "clr    %0\n"                                                   \
165 "2:\n\n\t"                                                              \
166         ".section .fixup,#alloc,#execinstr\n\t"                         \
167         ".align 4\n"                                                    \
168 "3:\n\t"                                                                \
169         "sethi  %%hi(2b), %0\n\t"                                       \
170         "clr    %1\n\t"                                                 \
171         "jmpl   %0 + %%lo(2b), %%g0\n\t"                                \
172         " mov   %3, %0\n\n\t"                                           \
173         ".previous\n\t"                                                 \
174         ".section __ex_table,\"a\"\n\t"                                 \
175         ".align 4\n\t"                                                  \
176         ".word  1b, 3b\n\n\t"                                           \
177         ".previous\n\t"                                                 \
178        : "=r" (ret), "=r" (x) : "r" (__m(addr)),                        \
179          "i" (-EFAULT))
180
181 #define __get_user_asm_ret(x,size,addr,retval)                          \
182 if (__builtin_constant_p(retval) && retval == -EFAULT)                  \
183 __asm__ __volatile__(                                                   \
184         "/* Get user asm ret, inline. */\n"                             \
185 "1:\t"  "ld"#size "a [%1] %%asi, %0\n\n\t"                              \
186         ".section __ex_table,\"a\"\n\t"                                 \
187         ".align 4\n\t"                                                  \
188         ".word  1b,__ret_efault\n\n\t"                                  \
189         ".previous\n\t"                                                 \
190        : "=r" (x) : "r" (__m(addr)));                                   \
191 else                                                                    \
192 __asm__ __volatile__(                                                   \
193         "/* Get user asm ret, inline. */\n"                             \
194 "1:\t"  "ld"#size "a [%1] %%asi, %0\n\n\t"                              \
195         ".section .fixup,#alloc,#execinstr\n\t"                         \
196         ".align 4\n"                                                    \
197 "3:\n\t"                                                                \
198         "ret\n\t"                                                       \
199         " restore %%g0, %2, %%o0\n\n\t"                                 \
200         ".previous\n\t"                                                 \
201         ".section __ex_table,\"a\"\n\t"                                 \
202         ".align 4\n\t"                                                  \
203         ".word  1b, 3b\n\n\t"                                           \
204         ".previous\n\t"                                                 \
205        : "=r" (x) : "r" (__m(addr)), "i" (retval))
206
207 extern int __get_user_bad(void);
208
209 extern unsigned long __must_check ___copy_from_user(void *to,
210                                                     const void __user *from,
211                                                     unsigned long size);
212 extern unsigned long copy_from_user_fixup(void *to, const void __user *from,
213                                           unsigned long size);
214 static inline unsigned long __must_check
215 copy_from_user(void *to, const void __user *from, unsigned long size)
216 {
217         unsigned long ret = ___copy_from_user(to, from, size);
218
219         if (unlikely(ret))
220                 ret = copy_from_user_fixup(to, from, size);
221
222         return ret;
223 }
224 #define __copy_from_user copy_from_user
225
226 extern unsigned long __must_check ___copy_to_user(void __user *to,
227                                                   const void *from,
228                                                   unsigned long size);
229 extern unsigned long copy_to_user_fixup(void __user *to, const void *from,
230                                         unsigned long size);
231 static inline unsigned long __must_check
232 copy_to_user(void __user *to, const void *from, unsigned long size)
233 {
234         unsigned long ret = ___copy_to_user(to, from, size);
235
236         if (unlikely(ret))
237                 ret = copy_to_user_fixup(to, from, size);
238         return ret;
239 }
240 #define __copy_to_user copy_to_user
241
242 extern unsigned long __must_check ___copy_in_user(void __user *to,
243                                                   const void __user *from,
244                                                   unsigned long size);
245 extern unsigned long copy_in_user_fixup(void __user *to, void __user *from,
246                                         unsigned long size);
247 static inline unsigned long __must_check
248 copy_in_user(void __user *to, void __user *from, unsigned long size)
249 {
250         unsigned long ret = ___copy_in_user(to, from, size);
251
252         if (unlikely(ret))
253                 ret = copy_in_user_fixup(to, from, size);
254         return ret;
255 }
256 #define __copy_in_user copy_in_user
257
258 extern unsigned long __must_check __clear_user(void __user *, unsigned long);
259
260 #define clear_user __clear_user
261
262 extern __must_check long strlen_user(const char __user *str);
263 extern __must_check long strnlen_user(const char __user *str, long n);
264
265 #define __copy_to_user_inatomic ___copy_to_user
266 #define __copy_from_user_inatomic ___copy_from_user
267
268 #endif  /* __ASSEMBLY__ */
269
270 #endif /* _ASM_UACCESS_H */