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uaccess_64.h
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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 struct pt_regs;
269 extern unsigned long compute_effective_address(struct pt_regs *,
270  unsigned int insn,
271  unsigned int rd);
272 
273 #endif /* __ASSEMBLY__ */
274 
275 #endif /* _ASM_UACCESS_H */
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