1 /* SPDX-License-Identifier: GPL-2.0 */
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
4 #ifndef __ASM_CSKY_UACCESS_H
5 #define __ASM_CSKY_UACCESS_H
8 * User space memory access functions
10 #include <linux/compiler.h>
11 #include <linux/errno.h>
12 #include <linux/types.h>
13 #include <linux/sched.h>
15 #include <linux/string.h>
16 #include <linux/version.h>
17 #include <asm/segment.h>
19 static inline int access_ok(const void *addr, unsigned long size)
21 unsigned long limit = current_thread_info()->addr_limit.seg;
23 return (((unsigned long)addr < limit) &&
24 ((unsigned long)(addr + size) < limit));
27 #define __addr_ok(addr) (access_ok(addr, 0))
29 extern int __put_user_bad(void);
32 * Tell gcc we read from memory instead of writing: this is because
33 * we do not write to any memory gcc knows about, so there are no
38 * These are the main single-value transfer routines. They automatically
39 * use the right size if we just have the right pointer type.
41 * This gets kind of ugly. We want to return _two_ values in "get_user()"
42 * and yet we don't want to do any pointers, because that is too much
43 * of a performance impact. Thus we have a few rather ugly macros here,
44 * and hide all the ugliness from the user.
46 * The "__xxx" versions of the user access functions are versions that
47 * do not verify the address space, that must have been done previously
48 * with a separate "access_ok()" call (this is used when we do multiple
49 * accesses to the same area of user memory).
51 * As we use the same address space for kernel and user data on
52 * Ckcore, we can just do these as direct assignments. (Of course, the
53 * exception handling means that it's no longer "just"...)
56 #define put_user(x, ptr) \
57 __put_user_check((x), (ptr), sizeof(*(ptr)))
59 #define __put_user(x, ptr) \
60 __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
62 #define __ptr(x) ((unsigned long *)(x))
64 #define get_user(x, ptr) \
65 __get_user_check((x), (ptr), sizeof(*(ptr)))
67 #define __get_user(x, ptr) \
68 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
70 #define __put_user_nocheck(x, ptr, size) \
73 typeof(*(ptr)) *__pu_addr = (ptr); \
74 typeof(*(ptr)) __pu_val = (typeof(*(ptr)))(x); \
76 __put_user_size(__pu_val, (__pu_addr), (size), \
81 #define __put_user_check(x, ptr, size) \
83 long __pu_err = -EFAULT; \
84 typeof(*(ptr)) *__pu_addr = (ptr); \
85 typeof(*(ptr)) __pu_val = (typeof(*(ptr)))(x); \
86 if (access_ok(__pu_addr, size) && __pu_addr) \
87 __put_user_size(__pu_val, __pu_addr, (size), __pu_err); \
91 #define __put_user_size(x, ptr, size, retval) \
96 __put_user_asm_b(x, ptr, retval); \
99 __put_user_asm_h(x, ptr, retval); \
102 __put_user_asm_w(x, ptr, retval); \
105 __put_user_asm_64(x, ptr, retval); \
113 * We don't tell gcc that we are accessing memory, but this is OK
114 * because we do not write to any memory gcc knows about, so there
115 * are no aliasing issues.
117 * Note that PC at a fault is the address *after* the faulting
120 #define __put_user_asm_b(x, ptr, err) \
124 "1: stb %1, (%2,0) \n" \
128 ".section __ex_table, \"a\" \n" \
133 : "=r"(err), "=r"(x), "=r"(ptr), "=r"(errcode) \
134 : "0"(err), "1"(x), "2"(ptr), "3"(-EFAULT) \
138 #define __put_user_asm_h(x, ptr, err) \
142 "1: sth %1, (%2,0) \n" \
146 ".section __ex_table, \"a\" \n" \
151 : "=r"(err), "=r"(x), "=r"(ptr), "=r"(errcode) \
152 : "0"(err), "1"(x), "2"(ptr), "3"(-EFAULT) \
156 #define __put_user_asm_w(x, ptr, err) \
160 "1: stw %1, (%2,0) \n" \
164 ".section __ex_table,\"a\" \n" \
169 : "=r"(err), "=r"(x), "=r"(ptr), "=r"(errcode) \
170 : "0"(err), "1"(x), "2"(ptr), "3"(-EFAULT) \
174 #define __put_user_asm_64(x, ptr, err) \
178 typeof(*(ptr))src = (typeof(*(ptr)))x; \
179 typeof(*(ptr))*psrc = &src; \
182 " ldw %3, (%1, 0) \n" \
183 "1: stw %3, (%2, 0) \n" \
184 " ldw %3, (%1, 4) \n" \
185 "2: stw %3, (%2, 4) \n" \
189 ".section __ex_table, \"a\" \n" \
195 : "=r"(err), "=r"(psrc), "=r"(ptr), \
196 "=r"(tmp), "=r"(errcode) \
197 : "0"(err), "1"(psrc), "2"(ptr), "3"(0), "4"(-EFAULT) \
201 #define __get_user_nocheck(x, ptr, size) \
204 __get_user_size(x, (ptr), (size), __gu_err); \
208 #define __get_user_check(x, ptr, size) \
210 int __gu_err = -EFAULT; \
211 const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \
212 if (access_ok(__gu_ptr, size) && __gu_ptr) \
213 __get_user_size(x, __gu_ptr, size, __gu_err); \
217 #define __get_user_size(x, ptr, size, retval) \
221 __get_user_asm_common((x), ptr, "ldb", retval); \
224 __get_user_asm_common((x), ptr, "ldh", retval); \
227 __get_user_asm_common((x), ptr, "ldw", retval); \
231 (retval) = __get_user_bad(); \
235 #define __get_user_asm_common(x, ptr, ins, err) \
239 "1: " ins " %1, (%4,0) \n" \
245 ".section __ex_table,\"a\" \n" \
250 : "=r"(err), "=r"(x), "=r"(errcode) \
251 : "0"(0), "r"(ptr), "2"(-EFAULT) \
255 extern int __get_user_bad(void);
257 #define ___copy_to_user(to, from, n) \
259 int w0, w1, w2, w3; \
261 "0: cmpnei %1, 0 \n" \
269 "1: cmplti %0, 16 \n" /* 4W */ \
271 " ldw %3, (%2, 0) \n" \
272 " ldw %4, (%2, 4) \n" \
273 " ldw %5, (%2, 8) \n" \
274 " ldw %6, (%2, 12) \n" \
275 "2: stw %3, (%1, 0) \n" \
276 "9: stw %4, (%1, 4) \n" \
277 "10: stw %5, (%1, 8) \n" \
278 "11: stw %6, (%1, 12) \n" \
283 "3: cmplti %0, 4 \n" /* 1W */ \
285 " ldw %3, (%2, 0) \n" \
286 "4: stw %3, (%1, 0) \n" \
291 "5: cmpnei %0, 0 \n" /* 1B */ \
293 " ldb %3, (%2, 0) \n" \
294 "6: stb %3, (%1, 0) \n" \
301 "12: subi %0, 4 \n" \
303 ".section __ex_table, \"a\" \n" \
313 : "=r"(n), "=r"(to), "=r"(from), "=r"(w0), \
314 "=r"(w1), "=r"(w2), "=r"(w3) \
315 : "0"(n), "1"(to), "2"(from) \
319 #define ___copy_from_user(to, from, n) \
324 "0: cmpnei %1, 0 \n" \
332 "1: cmplti %0, 16 \n" \
334 "2: ldw %3, (%2, 0) \n" \
335 "10: ldw %4, (%2, 4) \n" \
336 " stw %3, (%1, 0) \n" \
337 " stw %4, (%1, 4) \n" \
338 "11: ldw %3, (%2, 8) \n" \
339 "12: ldw %4, (%2, 12) \n" \
340 " stw %3, (%1, 8) \n" \
341 " stw %4, (%1, 12) \n" \
346 "3: cmplti %0, 4 \n" \
348 "4: ldw %3, (%2, 0) \n" \
349 " stw %3, (%1, 0) \n" \
354 "5: cmpnei %0, 0 \n" \
356 "6: ldb %3, (%2, 0) \n" \
357 " stb %3, (%1, 0) \n" \
362 "8: stw %3, (%1, 0) \n" \
367 "13: stw %3, (%1, 8) \n" \
370 ".section __ex_table, \"a\" \n" \
380 : "=r"(n), "=r"(to), "=r"(from), "=r"(nsave), \
382 : "0"(n), "1"(to), "2"(from) \
386 unsigned long raw_copy_from_user(void *to, const void *from, unsigned long n);
387 unsigned long raw_copy_to_user(void *to, const void *from, unsigned long n);
389 unsigned long clear_user(void *to, unsigned long n);
390 unsigned long __clear_user(void __user *to, unsigned long n);
392 long strncpy_from_user(char *dst, const char *src, long count);
393 long __strncpy_from_user(char *dst, const char *src, long count);
396 * Return the size of a string (including the ending 0)
398 * Return 0 on exception, a value greater than N if too long
400 long strnlen_user(const char *src, long n);
402 #define strlen_user(str) strnlen_user(str, 32767)
404 struct exception_table_entry {
406 unsigned long nextinsn;
409 extern int fixup_exception(struct pt_regs *regs);
411 #endif /* __ASM_CSKY_UACCESS_H */