1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * S390 version
4 * Copyright IBM Corp. 1999, 2000
5 * Author(s): Hartmut Penner (hp@de.ibm.com),
6 * Martin Schwidefsky (schwidefsky@de.ibm.com)
7 *
8 * Derived from "include/asm-i386/uaccess.h"
9 */
10 #ifndef __S390_UACCESS_H
11 #define __S390_UACCESS_H
12
13 /*
14 * User space memory access functions
15 */
16 #include <asm/asm-extable.h>
17 #include <asm/processor.h>
18 #include <asm/ctl_reg.h>
19 #include <asm/extable.h>
20 #include <asm/facility.h>
21 #include <asm-generic/access_ok.h>
22
23 void debug_user_asce(int exit);
24
25 unsigned long __must_check
26 raw_copy_from_user(void *to, const void __user *from, unsigned long n);
27
28 unsigned long __must_check
29 raw_copy_to_user(void __user *to, const void *from, unsigned long n);
30
31 #ifndef CONFIG_KASAN
32 #define INLINE_COPY_FROM_USER
33 #define INLINE_COPY_TO_USER
34 #endif
35
36 unsigned long __must_check
37 _copy_from_user_key(void *to, const void __user *from, unsigned long n, unsigned long key);
38
39 static __always_inline unsigned long __must_check
copy_from_user_key(void * to,const void __user * from,unsigned long n,unsigned long key)40 copy_from_user_key(void *to, const void __user *from, unsigned long n, unsigned long key)
41 {
42 if (likely(check_copy_size(to, n, false)))
43 n = _copy_from_user_key(to, from, n, key);
44 return n;
45 }
46
47 unsigned long __must_check
48 _copy_to_user_key(void __user *to, const void *from, unsigned long n, unsigned long key);
49
50 static __always_inline unsigned long __must_check
copy_to_user_key(void __user * to,const void * from,unsigned long n,unsigned long key)51 copy_to_user_key(void __user *to, const void *from, unsigned long n, unsigned long key)
52 {
53 if (likely(check_copy_size(from, n, true)))
54 n = _copy_to_user_key(to, from, n, key);
55 return n;
56 }
57
58 union oac {
59 unsigned int val;
60 struct {
61 struct {
62 unsigned short key : 4;
63 unsigned short : 4;
64 unsigned short as : 2;
65 unsigned short : 4;
66 unsigned short k : 1;
67 unsigned short a : 1;
68 } oac1;
69 struct {
70 unsigned short key : 4;
71 unsigned short : 4;
72 unsigned short as : 2;
73 unsigned short : 4;
74 unsigned short k : 1;
75 unsigned short a : 1;
76 } oac2;
77 };
78 };
79
80 int __noreturn __put_user_bad(void);
81
82 #define __put_user_asm(to, from, size) \
83 ({ \
84 union oac __oac_spec = { \
85 .oac1.as = PSW_BITS_AS_SECONDARY, \
86 .oac1.a = 1, \
87 }; \
88 int __rc; \
89 \
90 asm volatile( \
91 " lr 0,%[spec]\n" \
92 "0: mvcos %[_to],%[_from],%[_size]\n" \
93 "1: xr %[rc],%[rc]\n" \
94 "2:\n" \
95 EX_TABLE_UA_STORE(0b, 2b, %[rc]) \
96 EX_TABLE_UA_STORE(1b, 2b, %[rc]) \
97 : [rc] "=&d" (__rc), [_to] "+Q" (*(to)) \
98 : [_size] "d" (size), [_from] "Q" (*(from)), \
99 [spec] "d" (__oac_spec.val) \
100 : "cc", "0"); \
101 __rc; \
102 })
103
__put_user_fn(void * x,void __user * ptr,unsigned long size)104 static __always_inline int __put_user_fn(void *x, void __user *ptr, unsigned long size)
105 {
106 int rc;
107
108 switch (size) {
109 case 1:
110 rc = __put_user_asm((unsigned char __user *)ptr,
111 (unsigned char *)x,
112 size);
113 break;
114 case 2:
115 rc = __put_user_asm((unsigned short __user *)ptr,
116 (unsigned short *)x,
117 size);
118 break;
119 case 4:
120 rc = __put_user_asm((unsigned int __user *)ptr,
121 (unsigned int *)x,
122 size);
123 break;
124 case 8:
125 rc = __put_user_asm((unsigned long __user *)ptr,
126 (unsigned long *)x,
127 size);
128 break;
129 default:
130 __put_user_bad();
131 break;
132 }
133 return rc;
134 }
135
136 int __noreturn __get_user_bad(void);
137
138 #define __get_user_asm(to, from, size) \
139 ({ \
140 union oac __oac_spec = { \
141 .oac2.as = PSW_BITS_AS_SECONDARY, \
142 .oac2.a = 1, \
143 }; \
144 int __rc; \
145 \
146 asm volatile( \
147 " lr 0,%[spec]\n" \
148 "0: mvcos 0(%[_to]),%[_from],%[_size]\n" \
149 "1: xr %[rc],%[rc]\n" \
150 "2:\n" \
151 EX_TABLE_UA_LOAD_MEM(0b, 2b, %[rc], %[_to], %[_ksize]) \
152 EX_TABLE_UA_LOAD_MEM(1b, 2b, %[rc], %[_to], %[_ksize]) \
153 : [rc] "=&d" (__rc), "=Q" (*(to)) \
154 : [_size] "d" (size), [_from] "Q" (*(from)), \
155 [spec] "d" (__oac_spec.val), [_to] "a" (to), \
156 [_ksize] "K" (size) \
157 : "cc", "0"); \
158 __rc; \
159 })
160
__get_user_fn(void * x,const void __user * ptr,unsigned long size)161 static __always_inline int __get_user_fn(void *x, const void __user *ptr, unsigned long size)
162 {
163 int rc;
164
165 switch (size) {
166 case 1:
167 rc = __get_user_asm((unsigned char *)x,
168 (unsigned char __user *)ptr,
169 size);
170 break;
171 case 2:
172 rc = __get_user_asm((unsigned short *)x,
173 (unsigned short __user *)ptr,
174 size);
175 break;
176 case 4:
177 rc = __get_user_asm((unsigned int *)x,
178 (unsigned int __user *)ptr,
179 size);
180 break;
181 case 8:
182 rc = __get_user_asm((unsigned long *)x,
183 (unsigned long __user *)ptr,
184 size);
185 break;
186 default:
187 __get_user_bad();
188 break;
189 }
190 return rc;
191 }
192
193 /*
194 * These are the main single-value transfer routines. They automatically
195 * use the right size if we just have the right pointer type.
196 */
197 #define __put_user(x, ptr) \
198 ({ \
199 __typeof__(*(ptr)) __x = (x); \
200 int __pu_err = -EFAULT; \
201 \
202 __chk_user_ptr(ptr); \
203 switch (sizeof(*(ptr))) { \
204 case 1: \
205 case 2: \
206 case 4: \
207 case 8: \
208 __pu_err = __put_user_fn(&__x, ptr, sizeof(*(ptr))); \
209 break; \
210 default: \
211 __put_user_bad(); \
212 break; \
213 } \
214 __builtin_expect(__pu_err, 0); \
215 })
216
217 #define put_user(x, ptr) \
218 ({ \
219 might_fault(); \
220 __put_user(x, ptr); \
221 })
222
223 #define __get_user(x, ptr) \
224 ({ \
225 int __gu_err = -EFAULT; \
226 \
227 __chk_user_ptr(ptr); \
228 switch (sizeof(*(ptr))) { \
229 case 1: { \
230 unsigned char __x; \
231 \
232 __gu_err = __get_user_fn(&__x, ptr, sizeof(*(ptr))); \
233 (x) = *(__force __typeof__(*(ptr)) *)&__x; \
234 break; \
235 }; \
236 case 2: { \
237 unsigned short __x; \
238 \
239 __gu_err = __get_user_fn(&__x, ptr, sizeof(*(ptr))); \
240 (x) = *(__force __typeof__(*(ptr)) *)&__x; \
241 break; \
242 }; \
243 case 4: { \
244 unsigned int __x; \
245 \
246 __gu_err = __get_user_fn(&__x, ptr, sizeof(*(ptr))); \
247 (x) = *(__force __typeof__(*(ptr)) *)&__x; \
248 break; \
249 }; \
250 case 8: { \
251 unsigned long __x; \
252 \
253 __gu_err = __get_user_fn(&__x, ptr, sizeof(*(ptr))); \
254 (x) = *(__force __typeof__(*(ptr)) *)&__x; \
255 break; \
256 }; \
257 default: \
258 __get_user_bad(); \
259 break; \
260 } \
261 __builtin_expect(__gu_err, 0); \
262 })
263
264 #define get_user(x, ptr) \
265 ({ \
266 might_fault(); \
267 __get_user(x, ptr); \
268 })
269
270 /*
271 * Copy a null terminated string from userspace.
272 */
273 long __must_check strncpy_from_user(char *dst, const char __user *src, long count);
274
275 long __must_check strnlen_user(const char __user *src, long count);
276
277 /*
278 * Zero Userspace
279 */
280 unsigned long __must_check __clear_user(void __user *to, unsigned long size);
281
clear_user(void __user * to,unsigned long n)282 static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
283 {
284 might_fault();
285 return __clear_user(to, n);
286 }
287
288 int copy_to_user_real(void __user *dest, unsigned long src, unsigned long count);
289 void *s390_kernel_write(void *dst, const void *src, size_t size);
290
291 int __noreturn __put_kernel_bad(void);
292
293 #define __put_kernel_asm(val, to, insn) \
294 ({ \
295 int __rc; \
296 \
297 asm volatile( \
298 "0: " insn " %[_val],%[_to]\n" \
299 "1: xr %[rc],%[rc]\n" \
300 "2:\n" \
301 EX_TABLE_UA_STORE(0b, 2b, %[rc]) \
302 EX_TABLE_UA_STORE(1b, 2b, %[rc]) \
303 : [rc] "=d" (__rc), [_to] "+Q" (*(to)) \
304 : [_val] "d" (val) \
305 : "cc"); \
306 __rc; \
307 })
308
309 #define __put_kernel_nofault(dst, src, type, err_label) \
310 do { \
311 unsigned long __x = (unsigned long)(*((type *)(src))); \
312 int __pk_err; \
313 \
314 switch (sizeof(type)) { \
315 case 1: \
316 __pk_err = __put_kernel_asm(__x, (type *)(dst), "stc"); \
317 break; \
318 case 2: \
319 __pk_err = __put_kernel_asm(__x, (type *)(dst), "sth"); \
320 break; \
321 case 4: \
322 __pk_err = __put_kernel_asm(__x, (type *)(dst), "st"); \
323 break; \
324 case 8: \
325 __pk_err = __put_kernel_asm(__x, (type *)(dst), "stg"); \
326 break; \
327 default: \
328 __pk_err = __put_kernel_bad(); \
329 break; \
330 } \
331 if (unlikely(__pk_err)) \
332 goto err_label; \
333 } while (0)
334
335 int __noreturn __get_kernel_bad(void);
336
337 #define __get_kernel_asm(val, from, insn) \
338 ({ \
339 int __rc; \
340 \
341 asm volatile( \
342 "0: " insn " %[_val],%[_from]\n" \
343 "1: xr %[rc],%[rc]\n" \
344 "2:\n" \
345 EX_TABLE_UA_LOAD_REG(0b, 2b, %[rc], %[_val]) \
346 EX_TABLE_UA_LOAD_REG(1b, 2b, %[rc], %[_val]) \
347 : [rc] "=d" (__rc), [_val] "=d" (val) \
348 : [_from] "Q" (*(from)) \
349 : "cc"); \
350 __rc; \
351 })
352
353 #define __get_kernel_nofault(dst, src, type, err_label) \
354 do { \
355 int __gk_err; \
356 \
357 switch (sizeof(type)) { \
358 case 1: { \
359 unsigned char __x; \
360 \
361 __gk_err = __get_kernel_asm(__x, (type *)(src), "ic"); \
362 *((type *)(dst)) = (type)__x; \
363 break; \
364 }; \
365 case 2: { \
366 unsigned short __x; \
367 \
368 __gk_err = __get_kernel_asm(__x, (type *)(src), "lh"); \
369 *((type *)(dst)) = (type)__x; \
370 break; \
371 }; \
372 case 4: { \
373 unsigned int __x; \
374 \
375 __gk_err = __get_kernel_asm(__x, (type *)(src), "l"); \
376 *((type *)(dst)) = (type)__x; \
377 break; \
378 }; \
379 case 8: { \
380 unsigned long __x; \
381 \
382 __gk_err = __get_kernel_asm(__x, (type *)(src), "lg"); \
383 *((type *)(dst)) = (type)__x; \
384 break; \
385 }; \
386 default: \
387 __gk_err = __get_kernel_bad(); \
388 break; \
389 } \
390 if (unlikely(__gk_err)) \
391 goto err_label; \
392 } while (0)
393
394 #endif /* __S390_UACCESS_H */
395