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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* $Id: uaccess.h,v 1.35 2002/02/09 19:49:31 davem Exp $ */
2#ifndef _ASM_UACCESS_H
3#define _ASM_UACCESS_H
4
5/*
6 * User space memory access functions
7 */
8
9#ifdef __KERNEL__
10#include <linux/compiler.h>
11#include <linux/sched.h>
12#include <linux/string.h>
13#include <asm/a.out.h>
14#include <asm/asi.h>
15#include <asm/system.h>
16#include <asm/spitfire.h>
17#include <asm-generic/uaccess.h>
18#endif
19
20#ifndef __ASSEMBLY__
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) \
47do { \
48 set_thread_current_ds((val).seg); \
49 __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg)); \
50} while(0)
51
52static inline int __access_ok(const void __user * addr, unsigned long size)
53{
54 return 1;
55}
56
57static inline int access_ok(int type, const void __user * addr, unsigned long size)
58{
59 return 1;
60}
61
Linus Torvalds1da177e2005-04-16 15:20:36 -070062/*
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.
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 */
74
David S. Miller8cf14af2005-09-28 20:21:11 -070075struct exception_table_entry {
76 unsigned int insn, fixup;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077};
78
Linus Torvalds1da177e2005-04-16 15:20:36 -070079extern void __ret_efault(void);
David S. Miller5fd29752005-09-28 20:41:45 -070080extern void __retl_efault(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
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) ({ \
92unsigned 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) ({ \
97unsigned 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
104struct __large_struct { unsigned long buf[100]; };
105#define __m(x) ((struct __large_struct *)(x))
106
107#define __put_user_nocheck(data,addr,size) ({ \
108register int __pu_ret; \
109switch (size) { \
110case 1: __put_user_asm(data,b,addr,__pu_ret); break; \
111case 2: __put_user_asm(data,h,addr,__pu_ret); break; \
112case 4: __put_user_asm(data,w,addr,__pu_ret); break; \
113case 8: __put_user_asm(data,x,addr,__pu_ret); break; \
114default: __pu_ret = __put_user_bad(); break; \
115} __pu_ret; })
116
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117#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 "b 2b\n\t" \
127 " mov %3, %0\n\n\t" \
128 ".previous\n\t" \
David S. Miller4d000d52006-03-04 23:23:56 -0800129 ".section __ex_table,\"a\"\n\t" \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 ".align 4\n\t" \
131 ".word 1b, 3b\n\t" \
132 ".previous\n\n\t" \
133 : "=r" (ret) : "r" (x), "r" (__m(addr)), \
134 "i" (-EFAULT))
135
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136extern int __put_user_bad(void);
137
138#define __get_user_nocheck(data,addr,size,type) ({ \
139register int __gu_ret; \
140register unsigned long __gu_val; \
141switch (size) { \
142case 1: __get_user_asm(__gu_val,ub,addr,__gu_ret); break; \
143case 2: __get_user_asm(__gu_val,uh,addr,__gu_ret); break; \
144case 4: __get_user_asm(__gu_val,uw,addr,__gu_ret); break; \
145case 8: __get_user_asm(__gu_val,x,addr,__gu_ret); break; \
146default: __gu_val = 0; __gu_ret = __get_user_bad(); break; \
147} data = (type) __gu_val; __gu_ret; })
148
149#define __get_user_nocheck_ret(data,addr,size,type,retval) ({ \
150register unsigned long __gu_val __asm__ ("l1"); \
151switch (size) { \
152case 1: __get_user_asm_ret(__gu_val,ub,addr,retval); break; \
153case 2: __get_user_asm_ret(__gu_val,uh,addr,retval); break; \
154case 4: __get_user_asm_ret(__gu_val,uw,addr,retval); break; \
155case 8: __get_user_asm_ret(__gu_val,x,addr,retval); break; \
156default: if (__get_user_bad()) return retval; \
157} data = (type) __gu_val; })
158
159#define __get_user_asm(x,size,addr,ret) \
160__asm__ __volatile__( \
161 "/* Get user asm, inline. */\n" \
162"1:\t" "ld"#size "a [%2] %%asi, %1\n\t" \
163 "clr %0\n" \
164"2:\n\n\t" \
165 ".section .fixup,#alloc,#execinstr\n\t" \
166 ".align 4\n" \
167"3:\n\t" \
168 "clr %1\n\t" \
169 "b 2b\n\t" \
170 " mov %3, %0\n\n\t" \
171 ".previous\n\t" \
David S. Miller4d000d52006-03-04 23:23:56 -0800172 ".section __ex_table,\"a\"\n\t" \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 ".align 4\n\t" \
174 ".word 1b, 3b\n\n\t" \
175 ".previous\n\t" \
176 : "=r" (ret), "=r" (x) : "r" (__m(addr)), \
177 "i" (-EFAULT))
178
179#define __get_user_asm_ret(x,size,addr,retval) \
180if (__builtin_constant_p(retval) && retval == -EFAULT) \
181__asm__ __volatile__( \
182 "/* Get user asm ret, inline. */\n" \
183"1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \
David S. Miller4d000d52006-03-04 23:23:56 -0800184 ".section __ex_table,\"a\"\n\t" \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 ".align 4\n\t" \
186 ".word 1b,__ret_efault\n\n\t" \
187 ".previous\n\t" \
188 : "=r" (x) : "r" (__m(addr))); \
189else \
190__asm__ __volatile__( \
191 "/* Get user asm ret, inline. */\n" \
192"1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \
193 ".section .fixup,#alloc,#execinstr\n\t" \
194 ".align 4\n" \
195"3:\n\t" \
196 "ret\n\t" \
197 " restore %%g0, %2, %%o0\n\n\t" \
198 ".previous\n\t" \
David S. Miller4d000d52006-03-04 23:23:56 -0800199 ".section __ex_table,\"a\"\n\t" \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 ".align 4\n\t" \
201 ".word 1b, 3b\n\n\t" \
202 ".previous\n\t" \
203 : "=r" (x) : "r" (__m(addr)), "i" (retval))
204
205extern int __get_user_bad(void);
206
207extern unsigned long __must_check ___copy_from_user(void *to,
208 const void __user *from,
209 unsigned long size);
210extern unsigned long copy_from_user_fixup(void *to, const void __user *from,
211 unsigned long size);
212static inline unsigned long __must_check
213copy_from_user(void *to, const void __user *from, unsigned long size)
214{
215 unsigned long ret = ___copy_from_user(to, from, size);
216
David S. Millerefdc1e22005-09-28 21:06:47 -0700217 if (unlikely(ret))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 ret = copy_from_user_fixup(to, from, size);
219 return ret;
220}
221#define __copy_from_user copy_from_user
222
223extern unsigned long __must_check ___copy_to_user(void __user *to,
224 const void *from,
225 unsigned long size);
226extern unsigned long copy_to_user_fixup(void __user *to, const void *from,
227 unsigned long size);
228static inline unsigned long __must_check
229copy_to_user(void __user *to, const void *from, unsigned long size)
230{
231 unsigned long ret = ___copy_to_user(to, from, size);
232
David S. Millerefdc1e22005-09-28 21:06:47 -0700233 if (unlikely(ret))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 ret = copy_to_user_fixup(to, from, size);
235 return ret;
236}
237#define __copy_to_user copy_to_user
238
239extern unsigned long __must_check ___copy_in_user(void __user *to,
240 const void __user *from,
241 unsigned long size);
242extern unsigned long copy_in_user_fixup(void __user *to, void __user *from,
243 unsigned long size);
244static inline unsigned long __must_check
245copy_in_user(void __user *to, void __user *from, unsigned long size)
246{
247 unsigned long ret = ___copy_in_user(to, from, size);
248
David S. Millerefdc1e22005-09-28 21:06:47 -0700249 if (unlikely(ret))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 ret = copy_in_user_fixup(to, from, size);
251 return ret;
252}
253#define __copy_in_user copy_in_user
254
David S. Millerc857e3f2006-02-17 10:35:23 -0800255extern unsigned long __must_check __clear_user(void __user *, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256
257#define clear_user __clear_user
258
259extern long __must_check __strncpy_from_user(char *dest, const char __user *src, long count);
260
261#define strncpy_from_user __strncpy_from_user
262
263extern long __strlen_user(const char __user *);
264extern long __strnlen_user(const char __user *, long len);
265
266#define strlen_user __strlen_user
267#define strnlen_user __strnlen_user
268#define __copy_to_user_inatomic __copy_to_user
269#define __copy_from_user_inatomic __copy_from_user
270
271#endif /* __ASSEMBLY__ */
272
273#endif /* _ASM_UACCESS_H */