xref: /linux/arch/sparc/include/asm/uaccess_64.h (revision 98838d95075a5295f3478ceba18bcccf472e30f4)
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 #include <asm/extable_64.h>
17 #endif
18 
19 #ifndef __ASSEMBLY__
20 
21 #include <asm/processor.h>
22 
23 /*
24  * Sparc64 is segmented, though more like the M68K than the I386.
25  * We use the secondary ASI to address user memory, which references a
26  * completely different VM map, thus there is zero chance of the user
27  * doing something queer and tricking us into poking kernel memory.
28  *
29  * What is left here is basically what is needed for the other parts of
30  * the kernel that expect to be able to manipulate, erum, "segments".
31  * Or perhaps more properly, permissions.
32  *
33  * "For historical reasons, these macros are grossly misnamed." -Linus
34  */
35 
36 #define KERNEL_DS   ((mm_segment_t) { ASI_P })
37 #define USER_DS     ((mm_segment_t) { ASI_AIUS })	/* har har har */
38 
39 #define VERIFY_READ	0
40 #define VERIFY_WRITE	1
41 
42 #define get_fs() ((mm_segment_t){(current_thread_info()->current_ds)})
43 #define get_ds() (KERNEL_DS)
44 
45 #define segment_eq(a, b)  ((a).seg == (b).seg)
46 
47 #define set_fs(val)								\
48 do {										\
49 	current_thread_info()->current_ds = (val).seg;				\
50 	__asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg));	\
51 } while(0)
52 
53 /*
54  * Test whether a block of memory is a valid user space address.
55  * Returns 0 if the range is valid, nonzero otherwise.
56  */
57 static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, unsigned long limit)
58 {
59 	if (__builtin_constant_p(size))
60 		return addr > limit - size;
61 
62 	addr += size;
63 	if (addr < size)
64 		return true;
65 
66 	return addr > limit;
67 }
68 
69 #define __range_not_ok(addr, size, limit)                               \
70 ({                                                                      \
71 	__chk_user_ptr(addr);                                           \
72 	__chk_range_not_ok((unsigned long __force)(addr), size, limit); \
73 })
74 
75 static inline int __access_ok(const void __user * addr, unsigned long size)
76 {
77 	return 1;
78 }
79 
80 static inline int access_ok(int type, const void __user * addr, unsigned long size)
81 {
82 	return 1;
83 }
84 
85 void __ret_efault(void);
86 void __retl_efault(void);
87 
88 /* Uh, these should become the main single-value transfer routines..
89  * They automatically use the right size if we just have the right
90  * pointer type..
91  *
92  * This gets kind of ugly. We want to return _two_ values in "get_user()"
93  * and yet we don't want to do any pointers, because that is too much
94  * of a performance impact. Thus we have a few rather ugly macros here,
95  * and hide all the ugliness from the user.
96  */
97 #define put_user(x, ptr) ({ \
98 	unsigned long __pu_addr = (unsigned long)(ptr); \
99 	__chk_user_ptr(ptr); \
100 	__put_user_nocheck((__typeof__(*(ptr)))(x), __pu_addr, sizeof(*(ptr)));\
101 })
102 
103 #define get_user(x, ptr) ({ \
104 	unsigned long __gu_addr = (unsigned long)(ptr); \
105 	__chk_user_ptr(ptr); \
106 	__get_user_nocheck((x), __gu_addr, sizeof(*(ptr)), __typeof__(*(ptr)));\
107 })
108 
109 #define __put_user(x, ptr) put_user(x, ptr)
110 #define __get_user(x, ptr) get_user(x, ptr)
111 
112 struct __large_struct { unsigned long buf[100]; };
113 #define __m(x) ((struct __large_struct *)(x))
114 
115 #define __put_user_nocheck(data, addr, size) ({			\
116 	register int __pu_ret;					\
117 	switch (size) {						\
118 	case 1: __put_user_asm(data, b, addr, __pu_ret); break;	\
119 	case 2: __put_user_asm(data, h, addr, __pu_ret); break;	\
120 	case 4: __put_user_asm(data, w, addr, __pu_ret); break;	\
121 	case 8: __put_user_asm(data, x, addr, __pu_ret); break;	\
122 	default: __pu_ret = __put_user_bad(); break;		\
123 	}							\
124 	__pu_ret;						\
125 })
126 
127 #define __put_user_asm(x, size, addr, ret)				\
128 __asm__ __volatile__(							\
129 		"/* Put user asm, inline. */\n"				\
130 	"1:\t"	"st"#size "a %1, [%2] %%asi\n\t"			\
131 		"clr	%0\n"						\
132 	"2:\n\n\t"							\
133 		".section .fixup,#alloc,#execinstr\n\t"			\
134 		".align	4\n"						\
135 	"3:\n\t"							\
136 		"sethi	%%hi(2b), %0\n\t"				\
137 		"jmpl	%0 + %%lo(2b), %%g0\n\t"			\
138 		" mov	%3, %0\n\n\t"					\
139 		".previous\n\t"						\
140 		".section __ex_table,\"a\"\n\t"				\
141 		".align	4\n\t"						\
142 		".word	1b, 3b\n\t"					\
143 		".previous\n\n\t"					\
144 	       : "=r" (ret) : "r" (x), "r" (__m(addr)),			\
145 		 "i" (-EFAULT))
146 
147 int __put_user_bad(void);
148 
149 #define __get_user_nocheck(data, addr, size, type) ({			     \
150 	register int __gu_ret;						     \
151 	register unsigned long __gu_val;				     \
152 	switch (size) {							     \
153 		case 1: __get_user_asm(__gu_val, ub, addr, __gu_ret); break; \
154 		case 2: __get_user_asm(__gu_val, uh, addr, __gu_ret); break; \
155 		case 4: __get_user_asm(__gu_val, uw, addr, __gu_ret); break; \
156 		case 8: __get_user_asm(__gu_val, x, addr, __gu_ret); break;  \
157 		default:						     \
158 			__gu_val = 0;					     \
159 			__gu_ret = __get_user_bad();			     \
160 			break;						     \
161 	} 								     \
162 	data = (__force type) __gu_val;					     \
163 	 __gu_ret;							     \
164 })
165 
166 #define __get_user_asm(x, size, addr, ret)				\
167 __asm__ __volatile__(							\
168 		"/* Get user asm, inline. */\n"				\
169 	"1:\t"	"ld"#size "a [%2] %%asi, %1\n\t"			\
170 		"clr	%0\n"						\
171 	"2:\n\n\t"							\
172 		".section .fixup,#alloc,#execinstr\n\t"			\
173 		".align	4\n"						\
174 	"3:\n\t"							\
175 		"sethi	%%hi(2b), %0\n\t"				\
176 		"clr	%1\n\t"						\
177 		"jmpl	%0 + %%lo(2b), %%g0\n\t"			\
178 		" mov	%3, %0\n\n\t"					\
179 		".previous\n\t"						\
180 		".section __ex_table,\"a\"\n\t"				\
181 		".align	4\n\t"						\
182 		".word	1b, 3b\n\n\t"					\
183 		".previous\n\t"						\
184 	       : "=r" (ret), "=r" (x) : "r" (__m(addr)),		\
185 		 "i" (-EFAULT))
186 
187 int __get_user_bad(void);
188 
189 unsigned long __must_check ___copy_from_user(void *to,
190 					     const void __user *from,
191 					     unsigned long size);
192 unsigned long copy_from_user_fixup(void *to, const void __user *from,
193 				   unsigned long size);
194 static inline unsigned long __must_check
195 copy_from_user(void *to, const void __user *from, unsigned long size)
196 {
197 	unsigned long ret;
198 
199 	check_object_size(to, size, false);
200 
201 	ret = ___copy_from_user(to, from, size);
202 	if (unlikely(ret))
203 		ret = copy_from_user_fixup(to, from, size);
204 
205 	return ret;
206 }
207 #define __copy_from_user copy_from_user
208 
209 unsigned long __must_check ___copy_to_user(void __user *to,
210 					   const void *from,
211 					   unsigned long size);
212 unsigned long copy_to_user_fixup(void __user *to, const void *from,
213 				 unsigned long size);
214 static inline unsigned long __must_check
215 copy_to_user(void __user *to, const void *from, unsigned long size)
216 {
217 	unsigned long ret;
218 
219 	check_object_size(from, size, true);
220 
221 	ret = ___copy_to_user(to, from, size);
222 	if (unlikely(ret))
223 		ret = copy_to_user_fixup(to, from, size);
224 	return ret;
225 }
226 #define __copy_to_user copy_to_user
227 
228 unsigned long __must_check ___copy_in_user(void __user *to,
229 					   const void __user *from,
230 					   unsigned long size);
231 unsigned long copy_in_user_fixup(void __user *to, void __user *from,
232 				 unsigned long size);
233 static inline unsigned long __must_check
234 copy_in_user(void __user *to, void __user *from, unsigned long size)
235 {
236 	unsigned long ret = ___copy_in_user(to, from, size);
237 
238 	if (unlikely(ret))
239 		ret = copy_in_user_fixup(to, from, size);
240 	return ret;
241 }
242 #define __copy_in_user copy_in_user
243 
244 unsigned long __must_check __clear_user(void __user *, unsigned long);
245 
246 #define clear_user __clear_user
247 
248 __must_check long strlen_user(const char __user *str);
249 __must_check long strnlen_user(const char __user *str, long n);
250 
251 #define __copy_to_user_inatomic __copy_to_user
252 #define __copy_from_user_inatomic __copy_from_user
253 
254 struct pt_regs;
255 unsigned long compute_effective_address(struct pt_regs *,
256 					unsigned int insn,
257 					unsigned int rd);
258 
259 #endif  /* __ASSEMBLY__ */
260 
261 #endif /* _ASM_UACCESS_H */
262