1 #ifndef __PARISC_UACCESS_H
2 #define __PARISC_UACCESS_H
3
4 /*
5 * User space memory access functions
6 */
7 #include <asm/page.h>
8 #include <asm/cache.h>
9 #include <asm/errno.h>
10 #include <asm-generic/uaccess-unaligned.h>
11
12 #define VERIFY_READ 0
13 #define VERIFY_WRITE 1
14
15 #define KERNEL_DS ((mm_segment_t){0})
16 #define USER_DS ((mm_segment_t){1})
17
18 #define segment_eq(a,b) ((a).seg == (b).seg)
19
20 #define get_ds() (KERNEL_DS)
21 #define get_fs() (current_thread_info()->addr_limit)
22 #define set_fs(x) (current_thread_info()->addr_limit = (x))
23
24 /*
25 * Note that since kernel addresses are in a separate address space on
26 * parisc, we don't need to do anything for access_ok().
27 * We just let the page fault handler do the right thing. This also means
28 * that put_user is the same as __put_user, etc.
29 */
30
31 extern int __get_kernel_bad(void);
32 extern int __get_user_bad(void);
33 extern int __put_kernel_bad(void);
34 extern int __put_user_bad(void);
35
access_ok(int type,const void __user * addr,unsigned long size)36 static inline long access_ok(int type, const void __user * addr,
37 unsigned long size)
38 {
39 return 1;
40 }
41
42 #define put_user __put_user
43 #define get_user __get_user
44
45 #if !defined(CONFIG_64BIT)
46 #define LDD_KERNEL(ptr) __get_kernel_bad();
47 #define LDD_USER(ptr) __get_user_bad();
48 #define STD_KERNEL(x, ptr) __put_kernel_asm64(x,ptr)
49 #define STD_USER(x, ptr) __put_user_asm64(x,ptr)
50 #define ASM_WORD_INSN ".word\t"
51 #else
52 #define LDD_KERNEL(ptr) __get_kernel_asm("ldd",ptr)
53 #define LDD_USER(ptr) __get_user_asm("ldd",ptr)
54 #define STD_KERNEL(x, ptr) __put_kernel_asm("std",x,ptr)
55 #define STD_USER(x, ptr) __put_user_asm("std",x,ptr)
56 #define ASM_WORD_INSN ".dword\t"
57 #endif
58
59 /*
60 * The exception table contains two values: the first is an address
61 * for an instruction that is allowed to fault, and the second is
62 * the address to the fixup routine.
63 */
64
65 struct exception_table_entry {
66 unsigned long insn; /* address of insn that is allowed to fault. */
67 long fixup; /* fixup routine */
68 };
69
70 #define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
71 ".section __ex_table,\"aw\"\n" \
72 ASM_WORD_INSN #fault_addr ", " #except_addr "\n\t" \
73 ".previous\n"
74
75 /*
76 * The page fault handler stores, in a per-cpu area, the following information
77 * if a fixup routine is available.
78 */
79 struct exception_data {
80 unsigned long fault_ip;
81 unsigned long fault_space;
82 unsigned long fault_addr;
83 };
84
85 #define __get_user(x,ptr) \
86 ({ \
87 register long __gu_err __asm__ ("r8") = 0; \
88 register long __gu_val __asm__ ("r9") = 0; \
89 \
90 if (segment_eq(get_fs(),KERNEL_DS)) { \
91 switch (sizeof(*(ptr))) { \
92 case 1: __get_kernel_asm("ldb",ptr); break; \
93 case 2: __get_kernel_asm("ldh",ptr); break; \
94 case 4: __get_kernel_asm("ldw",ptr); break; \
95 case 8: LDD_KERNEL(ptr); break; \
96 default: __get_kernel_bad(); break; \
97 } \
98 } \
99 else { \
100 switch (sizeof(*(ptr))) { \
101 case 1: __get_user_asm("ldb",ptr); break; \
102 case 2: __get_user_asm("ldh",ptr); break; \
103 case 4: __get_user_asm("ldw",ptr); break; \
104 case 8: LDD_USER(ptr); break; \
105 default: __get_user_bad(); break; \
106 } \
107 } \
108 \
109 (x) = (__typeof__(*(ptr))) __gu_val; \
110 __gu_err; \
111 })
112
113 #define __get_kernel_asm(ldx,ptr) \
114 __asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \
115 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
116 : "=r"(__gu_val), "=r"(__gu_err) \
117 : "r"(ptr), "1"(__gu_err) \
118 : "r1");
119
120 #define __get_user_asm(ldx,ptr) \
121 __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \
122 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_get_user_skip_1)\
123 : "=r"(__gu_val), "=r"(__gu_err) \
124 : "r"(ptr), "1"(__gu_err) \
125 : "r1");
126
127 #define __put_user(x,ptr) \
128 ({ \
129 register long __pu_err __asm__ ("r8") = 0; \
130 __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \
131 \
132 if (segment_eq(get_fs(),KERNEL_DS)) { \
133 switch (sizeof(*(ptr))) { \
134 case 1: __put_kernel_asm("stb",__x,ptr); break; \
135 case 2: __put_kernel_asm("sth",__x,ptr); break; \
136 case 4: __put_kernel_asm("stw",__x,ptr); break; \
137 case 8: STD_KERNEL(__x,ptr); break; \
138 default: __put_kernel_bad(); break; \
139 } \
140 } \
141 else { \
142 switch (sizeof(*(ptr))) { \
143 case 1: __put_user_asm("stb",__x,ptr); break; \
144 case 2: __put_user_asm("sth",__x,ptr); break; \
145 case 4: __put_user_asm("stw",__x,ptr); break; \
146 case 8: STD_USER(__x,ptr); break; \
147 default: __put_user_bad(); break; \
148 } \
149 } \
150 \
151 __pu_err; \
152 })
153
154 /*
155 * The "__put_user/kernel_asm()" macros tell gcc they read from memory
156 * instead of writing. This is because they do not write to any memory
157 * gcc knows about, so there are no aliasing issues. These macros must
158 * also be aware that "fixup_put_user_skip_[12]" are executed in the
159 * context of the fault, and any registers used there must be listed
160 * as clobbers. In this case only "r1" is used by the current routines.
161 * r8/r9 are already listed as err/val.
162 */
163
164 #define __put_kernel_asm(stx,x,ptr) \
165 __asm__ __volatile__ ( \
166 "\n1:\t" stx "\t%2,0(%1)\n\t" \
167 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\
168 : "=r"(__pu_err) \
169 : "r"(ptr), "r"(x), "0"(__pu_err) \
170 : "r1")
171
172 #define __put_user_asm(stx,x,ptr) \
173 __asm__ __volatile__ ( \
174 "\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \
175 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\
176 : "=r"(__pu_err) \
177 : "r"(ptr), "r"(x), "0"(__pu_err) \
178 : "r1")
179
180
181 #if !defined(CONFIG_64BIT)
182
183 #define __put_kernel_asm64(__val,ptr) do { \
184 u64 __val64 = (u64)(__val); \
185 u32 hi = (__val64) >> 32; \
186 u32 lo = (__val64) & 0xffffffff; \
187 __asm__ __volatile__ ( \
188 "\n1:\tstw %2,0(%1)" \
189 "\n2:\tstw %3,4(%1)\n\t" \
190 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\
191 ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\
192 : "=r"(__pu_err) \
193 : "r"(ptr), "r"(hi), "r"(lo), "0"(__pu_err) \
194 : "r1"); \
195 } while (0)
196
197 #define __put_user_asm64(__val,ptr) do { \
198 u64 __val64 = (u64)(__val); \
199 u32 hi = (__val64) >> 32; \
200 u32 lo = (__val64) & 0xffffffff; \
201 __asm__ __volatile__ ( \
202 "\n1:\tstw %2,0(%%sr3,%1)" \
203 "\n2:\tstw %3,4(%%sr3,%1)\n\t" \
204 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\
205 ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\
206 : "=r"(__pu_err) \
207 : "r"(ptr), "r"(hi), "r"(lo), "0"(__pu_err) \
208 : "r1"); \
209 } while (0)
210
211 #endif /* !defined(CONFIG_64BIT) */
212
213
214 /*
215 * Complex access routines -- external declarations
216 */
217
218 extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
219 extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
220 extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
221 extern long lstrncpy_from_user(char *, const char __user *, long);
222 extern unsigned lclear_user(void __user *,unsigned long);
223 extern long lstrnlen_user(const char __user *,long);
224
225 /*
226 * Complex access routines -- macros
227 */
228
229 #define strncpy_from_user lstrncpy_from_user
230 #define strnlen_user lstrnlen_user
231 #define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
232 #define clear_user lclear_user
233 #define __clear_user lclear_user
234
235 unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len);
236 #define __copy_to_user copy_to_user
237 unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len);
238 unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len);
239 #define __copy_in_user copy_in_user
240 #define __copy_to_user_inatomic __copy_to_user
241 #define __copy_from_user_inatomic __copy_from_user
242
243 extern void copy_from_user_overflow(void)
244 #ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
245 __compiletime_error("copy_from_user() buffer size is not provably correct")
246 #else
247 __compiletime_warning("copy_from_user() buffer size is not provably correct")
248 #endif
249 ;
250
copy_from_user(void * to,const void __user * from,unsigned long n)251 static inline unsigned long __must_check copy_from_user(void *to,
252 const void __user *from,
253 unsigned long n)
254 {
255 int sz = __compiletime_object_size(to);
256 int ret = -EFAULT;
257
258 if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n))
259 ret = __copy_from_user(to, from, n);
260 else
261 copy_from_user_overflow();
262
263 return ret;
264 }
265
266 struct pt_regs;
267 int fixup_exception(struct pt_regs *regs);
268
269 #endif /* __PARISC_UACCESS_H */
270