Commit | Line | Data |
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457f2180 HC |
1 | /* |
2 | * Standard user space access functions based on mvcp/mvcs and doing | |
3 | * interesting things in the secondary space mode. | |
4 | * | |
5 | * Copyright IBM Corp. 2006,2014 | |
6 | * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), | |
7 | * Gerald Schaefer (gerald.schaefer@de.ibm.com) | |
8 | */ | |
9 | ||
10 | #include <linux/jump_label.h> | |
11 | #include <linux/uaccess.h> | |
12 | #include <linux/export.h> | |
13 | #include <linux/errno.h> | |
14 | #include <linux/mm.h> | |
15 | #include <asm/mmu_context.h> | |
16 | #include <asm/facility.h> | |
17 | ||
ed79e946 | 18 | static DEFINE_STATIC_KEY_FALSE(have_mvcos); |
457f2180 HC |
19 | |
20 | static inline unsigned long copy_from_user_mvcos(void *x, const void __user *ptr, | |
21 | unsigned long size) | |
22 | { | |
23 | register unsigned long reg0 asm("0") = 0x81UL; | |
24 | unsigned long tmp1, tmp2; | |
25 | ||
26 | tmp1 = -4096UL; | |
27 | asm volatile( | |
28 | "0: .insn ss,0xc80000000000,0(%0,%2),0(%1),0\n" | |
29 | "9: jz 7f\n" | |
5a79859a HC |
30 | "1: algr %0,%3\n" |
31 | " slgr %1,%3\n" | |
32 | " slgr %2,%3\n" | |
457f2180 HC |
33 | " j 0b\n" |
34 | "2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */ | |
35 | " nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */ | |
5a79859a HC |
36 | " slgr %4,%1\n" |
37 | " clgr %0,%4\n" /* copy crosses next page boundary? */ | |
457f2180 HC |
38 | " jnh 4f\n" |
39 | "3: .insn ss,0xc80000000000,0(%4,%2),0(%1),0\n" | |
5a79859a HC |
40 | "10:slgr %0,%4\n" |
41 | " algr %2,%4\n" | |
42 | "4: lghi %4,-1\n" | |
43 | " algr %4,%0\n" /* copy remaining size, subtract 1 */ | |
457f2180 HC |
44 | " bras %3,6f\n" /* memset loop */ |
45 | " xc 0(1,%2),0(%2)\n" | |
46 | "5: xc 0(256,%2),0(%2)\n" | |
47 | " la %2,256(%2)\n" | |
5a79859a | 48 | "6: aghi %4,-256\n" |
457f2180 HC |
49 | " jnm 5b\n" |
50 | " ex %4,0(%3)\n" | |
51 | " j 8f\n" | |
b8ac5e2f | 52 | "7: slgr %0,%0\n" |
457f2180 HC |
53 | "8:\n" |
54 | EX_TABLE(0b,2b) EX_TABLE(3b,4b) EX_TABLE(9b,2b) EX_TABLE(10b,4b) | |
55 | : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) | |
56 | : "d" (reg0) : "cc", "memory"); | |
57 | return size; | |
58 | } | |
59 | ||
60 | static inline unsigned long copy_from_user_mvcp(void *x, const void __user *ptr, | |
61 | unsigned long size) | |
62 | { | |
63 | unsigned long tmp1, tmp2; | |
64 | ||
beef560b | 65 | load_kernel_asce(); |
457f2180 HC |
66 | tmp1 = -256UL; |
67 | asm volatile( | |
68 | " sacf 0\n" | |
69 | "0: mvcp 0(%0,%2),0(%1),%3\n" | |
70 | "10:jz 8f\n" | |
5a79859a | 71 | "1: algr %0,%3\n" |
457f2180 HC |
72 | " la %1,256(%1)\n" |
73 | " la %2,256(%2)\n" | |
74 | "2: mvcp 0(%0,%2),0(%1),%3\n" | |
75 | "11:jnz 1b\n" | |
76 | " j 8f\n" | |
77 | "3: la %4,255(%1)\n" /* %4 = ptr + 255 */ | |
5a79859a | 78 | " lghi %3,-4096\n" |
457f2180 | 79 | " nr %4,%3\n" /* %4 = (ptr + 255) & -4096 */ |
5a79859a HC |
80 | " slgr %4,%1\n" |
81 | " clgr %0,%4\n" /* copy crosses next page boundary? */ | |
457f2180 HC |
82 | " jnh 5f\n" |
83 | "4: mvcp 0(%4,%2),0(%1),%3\n" | |
5a79859a HC |
84 | "12:slgr %0,%4\n" |
85 | " algr %2,%4\n" | |
86 | "5: lghi %4,-1\n" | |
87 | " algr %4,%0\n" /* copy remaining size, subtract 1 */ | |
457f2180 HC |
88 | " bras %3,7f\n" /* memset loop */ |
89 | " xc 0(1,%2),0(%2)\n" | |
90 | "6: xc 0(256,%2),0(%2)\n" | |
91 | " la %2,256(%2)\n" | |
5a79859a | 92 | "7: aghi %4,-256\n" |
457f2180 HC |
93 | " jnm 6b\n" |
94 | " ex %4,0(%3)\n" | |
95 | " j 9f\n" | |
b8ac5e2f | 96 | "8: slgr %0,%0\n" |
457f2180 HC |
97 | "9: sacf 768\n" |
98 | EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,5b) | |
99 | EX_TABLE(10b,3b) EX_TABLE(11b,3b) EX_TABLE(12b,5b) | |
100 | : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) | |
101 | : : "cc", "memory"); | |
102 | return size; | |
103 | } | |
104 | ||
105 | unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n) | |
106 | { | |
97433ea4 | 107 | check_object_size(to, n, false); |
ed79e946 | 108 | if (static_branch_likely(&have_mvcos)) |
457f2180 HC |
109 | return copy_from_user_mvcos(to, from, n); |
110 | return copy_from_user_mvcp(to, from, n); | |
111 | } | |
112 | EXPORT_SYMBOL(__copy_from_user); | |
113 | ||
114 | static inline unsigned long copy_to_user_mvcos(void __user *ptr, const void *x, | |
115 | unsigned long size) | |
116 | { | |
117 | register unsigned long reg0 asm("0") = 0x810000UL; | |
118 | unsigned long tmp1, tmp2; | |
119 | ||
120 | tmp1 = -4096UL; | |
121 | asm volatile( | |
122 | "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n" | |
123 | "6: jz 4f\n" | |
5a79859a HC |
124 | "1: algr %0,%3\n" |
125 | " slgr %1,%3\n" | |
126 | " slgr %2,%3\n" | |
457f2180 HC |
127 | " j 0b\n" |
128 | "2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */ | |
129 | " nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */ | |
5a79859a HC |
130 | " slgr %4,%1\n" |
131 | " clgr %0,%4\n" /* copy crosses next page boundary? */ | |
457f2180 HC |
132 | " jnh 5f\n" |
133 | "3: .insn ss,0xc80000000000,0(%4,%1),0(%2),0\n" | |
5a79859a | 134 | "7: slgr %0,%4\n" |
457f2180 | 135 | " j 5f\n" |
5a79859a | 136 | "4: slgr %0,%0\n" |
457f2180 HC |
137 | "5:\n" |
138 | EX_TABLE(0b,2b) EX_TABLE(3b,5b) EX_TABLE(6b,2b) EX_TABLE(7b,5b) | |
139 | : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) | |
140 | : "d" (reg0) : "cc", "memory"); | |
141 | return size; | |
142 | } | |
143 | ||
144 | static inline unsigned long copy_to_user_mvcs(void __user *ptr, const void *x, | |
145 | unsigned long size) | |
146 | { | |
147 | unsigned long tmp1, tmp2; | |
148 | ||
beef560b | 149 | load_kernel_asce(); |
457f2180 HC |
150 | tmp1 = -256UL; |
151 | asm volatile( | |
152 | " sacf 0\n" | |
153 | "0: mvcs 0(%0,%1),0(%2),%3\n" | |
154 | "7: jz 5f\n" | |
5a79859a | 155 | "1: algr %0,%3\n" |
457f2180 HC |
156 | " la %1,256(%1)\n" |
157 | " la %2,256(%2)\n" | |
158 | "2: mvcs 0(%0,%1),0(%2),%3\n" | |
159 | "8: jnz 1b\n" | |
160 | " j 5f\n" | |
161 | "3: la %4,255(%1)\n" /* %4 = ptr + 255 */ | |
5a79859a | 162 | " lghi %3,-4096\n" |
457f2180 | 163 | " nr %4,%3\n" /* %4 = (ptr + 255) & -4096 */ |
5a79859a HC |
164 | " slgr %4,%1\n" |
165 | " clgr %0,%4\n" /* copy crosses next page boundary? */ | |
457f2180 HC |
166 | " jnh 6f\n" |
167 | "4: mvcs 0(%4,%1),0(%2),%3\n" | |
5a79859a | 168 | "9: slgr %0,%4\n" |
457f2180 | 169 | " j 6f\n" |
5a79859a | 170 | "5: slgr %0,%0\n" |
457f2180 HC |
171 | "6: sacf 768\n" |
172 | EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,6b) | |
173 | EX_TABLE(7b,3b) EX_TABLE(8b,3b) EX_TABLE(9b,6b) | |
174 | : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) | |
175 | : : "cc", "memory"); | |
176 | return size; | |
177 | } | |
178 | ||
179 | unsigned long __copy_to_user(void __user *to, const void *from, unsigned long n) | |
180 | { | |
97433ea4 | 181 | check_object_size(from, n, true); |
ed79e946 | 182 | if (static_branch_likely(&have_mvcos)) |
457f2180 HC |
183 | return copy_to_user_mvcos(to, from, n); |
184 | return copy_to_user_mvcs(to, from, n); | |
185 | } | |
186 | EXPORT_SYMBOL(__copy_to_user); | |
187 | ||
188 | static inline unsigned long copy_in_user_mvcos(void __user *to, const void __user *from, | |
189 | unsigned long size) | |
190 | { | |
191 | register unsigned long reg0 asm("0") = 0x810081UL; | |
192 | unsigned long tmp1, tmp2; | |
193 | ||
194 | tmp1 = -4096UL; | |
195 | /* FIXME: copy with reduced length. */ | |
196 | asm volatile( | |
197 | "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n" | |
198 | " jz 2f\n" | |
5a79859a HC |
199 | "1: algr %0,%3\n" |
200 | " slgr %1,%3\n" | |
201 | " slgr %2,%3\n" | |
457f2180 | 202 | " j 0b\n" |
5a79859a | 203 | "2:slgr %0,%0\n" |
457f2180 HC |
204 | "3: \n" |
205 | EX_TABLE(0b,3b) | |
206 | : "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2) | |
207 | : "d" (reg0) : "cc", "memory"); | |
208 | return size; | |
209 | } | |
210 | ||
211 | static inline unsigned long copy_in_user_mvc(void __user *to, const void __user *from, | |
212 | unsigned long size) | |
213 | { | |
214 | unsigned long tmp1; | |
215 | ||
beef560b | 216 | load_kernel_asce(); |
457f2180 HC |
217 | asm volatile( |
218 | " sacf 256\n" | |
5a79859a | 219 | " aghi %0,-1\n" |
457f2180 HC |
220 | " jo 5f\n" |
221 | " bras %3,3f\n" | |
5a79859a | 222 | "0: aghi %0,257\n" |
457f2180 HC |
223 | "1: mvc 0(1,%1),0(%2)\n" |
224 | " la %1,1(%1)\n" | |
225 | " la %2,1(%2)\n" | |
5a79859a | 226 | " aghi %0,-1\n" |
457f2180 HC |
227 | " jnz 1b\n" |
228 | " j 5f\n" | |
229 | "2: mvc 0(256,%1),0(%2)\n" | |
230 | " la %1,256(%1)\n" | |
231 | " la %2,256(%2)\n" | |
5a79859a | 232 | "3: aghi %0,-256\n" |
457f2180 HC |
233 | " jnm 2b\n" |
234 | "4: ex %0,1b-0b(%3)\n" | |
5a79859a | 235 | "5: slgr %0,%0\n" |
457f2180 HC |
236 | "6: sacf 768\n" |
237 | EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b) | |
238 | : "+a" (size), "+a" (to), "+a" (from), "=a" (tmp1) | |
239 | : : "cc", "memory"); | |
240 | return size; | |
241 | } | |
242 | ||
243 | unsigned long __copy_in_user(void __user *to, const void __user *from, unsigned long n) | |
244 | { | |
ed79e946 | 245 | if (static_branch_likely(&have_mvcos)) |
457f2180 HC |
246 | return copy_in_user_mvcos(to, from, n); |
247 | return copy_in_user_mvc(to, from, n); | |
248 | } | |
249 | EXPORT_SYMBOL(__copy_in_user); | |
250 | ||
251 | static inline unsigned long clear_user_mvcos(void __user *to, unsigned long size) | |
252 | { | |
253 | register unsigned long reg0 asm("0") = 0x810000UL; | |
254 | unsigned long tmp1, tmp2; | |
255 | ||
256 | tmp1 = -4096UL; | |
257 | asm volatile( | |
258 | "0: .insn ss,0xc80000000000,0(%0,%1),0(%4),0\n" | |
259 | " jz 4f\n" | |
5a79859a HC |
260 | "1: algr %0,%2\n" |
261 | " slgr %1,%2\n" | |
457f2180 HC |
262 | " j 0b\n" |
263 | "2: la %3,4095(%1)\n"/* %4 = to + 4095 */ | |
264 | " nr %3,%2\n" /* %4 = (to + 4095) & -4096 */ | |
5a79859a HC |
265 | " slgr %3,%1\n" |
266 | " clgr %0,%3\n" /* copy crosses next page boundary? */ | |
457f2180 HC |
267 | " jnh 5f\n" |
268 | "3: .insn ss,0xc80000000000,0(%3,%1),0(%4),0\n" | |
5a79859a | 269 | " slgr %0,%3\n" |
457f2180 | 270 | " j 5f\n" |
b8ac5e2f | 271 | "4: slgr %0,%0\n" |
457f2180 HC |
272 | "5:\n" |
273 | EX_TABLE(0b,2b) EX_TABLE(3b,5b) | |
274 | : "+a" (size), "+a" (to), "+a" (tmp1), "=a" (tmp2) | |
275 | : "a" (empty_zero_page), "d" (reg0) : "cc", "memory"); | |
276 | return size; | |
277 | } | |
278 | ||
279 | static inline unsigned long clear_user_xc(void __user *to, unsigned long size) | |
280 | { | |
281 | unsigned long tmp1, tmp2; | |
282 | ||
beef560b | 283 | load_kernel_asce(); |
457f2180 HC |
284 | asm volatile( |
285 | " sacf 256\n" | |
5a79859a | 286 | " aghi %0,-1\n" |
457f2180 HC |
287 | " jo 5f\n" |
288 | " bras %3,3f\n" | |
289 | " xc 0(1,%1),0(%1)\n" | |
5a79859a | 290 | "0: aghi %0,257\n" |
457f2180 HC |
291 | " la %2,255(%1)\n" /* %2 = ptr + 255 */ |
292 | " srl %2,12\n" | |
293 | " sll %2,12\n" /* %2 = (ptr + 255) & -4096 */ | |
5a79859a HC |
294 | " slgr %2,%1\n" |
295 | " clgr %0,%2\n" /* clear crosses next page boundary? */ | |
457f2180 | 296 | " jnh 5f\n" |
5a79859a | 297 | " aghi %2,-1\n" |
457f2180 | 298 | "1: ex %2,0(%3)\n" |
5a79859a HC |
299 | " aghi %2,1\n" |
300 | " slgr %0,%2\n" | |
457f2180 HC |
301 | " j 5f\n" |
302 | "2: xc 0(256,%1),0(%1)\n" | |
303 | " la %1,256(%1)\n" | |
5a79859a | 304 | "3: aghi %0,-256\n" |
457f2180 HC |
305 | " jnm 2b\n" |
306 | "4: ex %0,0(%3)\n" | |
5a79859a | 307 | "5: slgr %0,%0\n" |
457f2180 HC |
308 | "6: sacf 768\n" |
309 | EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b) | |
310 | : "+a" (size), "+a" (to), "=a" (tmp1), "=a" (tmp2) | |
311 | : : "cc", "memory"); | |
312 | return size; | |
313 | } | |
314 | ||
315 | unsigned long __clear_user(void __user *to, unsigned long size) | |
316 | { | |
ed79e946 | 317 | if (static_branch_likely(&have_mvcos)) |
457f2180 HC |
318 | return clear_user_mvcos(to, size); |
319 | return clear_user_xc(to, size); | |
320 | } | |
321 | EXPORT_SYMBOL(__clear_user); | |
322 | ||
323 | static inline unsigned long strnlen_user_srst(const char __user *src, | |
324 | unsigned long size) | |
325 | { | |
326 | register unsigned long reg0 asm("0") = 0; | |
327 | unsigned long tmp1, tmp2; | |
328 | ||
457f2180 HC |
329 | asm volatile( |
330 | " la %2,0(%1)\n" | |
331 | " la %3,0(%0,%1)\n" | |
5a79859a | 332 | " slgr %0,%0\n" |
457f2180 HC |
333 | " sacf 256\n" |
334 | "0: srst %3,%2\n" | |
335 | " jo 0b\n" | |
336 | " la %0,1(%3)\n" /* strnlen_user results includes \0 */ | |
5a79859a | 337 | " slgr %0,%1\n" |
457f2180 HC |
338 | "1: sacf 768\n" |
339 | EX_TABLE(0b,1b) | |
340 | : "+a" (size), "+a" (src), "=a" (tmp1), "=a" (tmp2) | |
341 | : "d" (reg0) : "cc", "memory"); | |
342 | return size; | |
343 | } | |
344 | ||
345 | unsigned long __strnlen_user(const char __user *src, unsigned long size) | |
346 | { | |
fa255f51 HC |
347 | if (unlikely(!size)) |
348 | return 0; | |
beef560b | 349 | load_kernel_asce(); |
457f2180 HC |
350 | return strnlen_user_srst(src, size); |
351 | } | |
352 | EXPORT_SYMBOL(__strnlen_user); | |
353 | ||
354 | long __strncpy_from_user(char *dst, const char __user *src, long size) | |
355 | { | |
356 | size_t done, len, offset, len_str; | |
357 | ||
358 | if (unlikely(size <= 0)) | |
359 | return 0; | |
360 | done = 0; | |
361 | do { | |
362 | offset = (size_t)src & ~PAGE_MASK; | |
363 | len = min(size - done, PAGE_SIZE - offset); | |
364 | if (copy_from_user(dst, src, len)) | |
365 | return -EFAULT; | |
366 | len_str = strnlen(dst, len); | |
367 | done += len_str; | |
368 | src += len_str; | |
369 | dst += len_str; | |
370 | } while ((len_str == len) && (done < size)); | |
371 | return done; | |
372 | } | |
373 | EXPORT_SYMBOL(__strncpy_from_user); | |
374 | ||
457f2180 HC |
375 | static int __init uaccess_init(void) |
376 | { | |
cabc4abe | 377 | if (test_facility(27)) |
ed79e946 | 378 | static_branch_enable(&have_mvcos); |
457f2180 HC |
379 | return 0; |
380 | } | |
381 | early_initcall(uaccess_init); |