1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ARCH_POWERPC_UACCESS_H
3 #define _ARCH_POWERPC_UACCESS_H
5 #include <asm/ppc_asm.h>
6 #include <asm/processor.h>
8 #include <asm/extable.h>
11 * The fs value determines whether argument validity checking should be
12 * performed or not. If get_fs() == USER_DS, checking is performed, with
13 * get_fs() == KERNEL_DS, checking is bypassed.
15 * For historical reasons, these macros are grossly misnamed.
17 * The fs/ds values are now the highest legal address in the "segment".
18 * This simplifies the checking in the routines below.
21 #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
23 #define KERNEL_DS MAKE_MM_SEG(~0UL)
25 /* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */
26 #define USER_DS MAKE_MM_SEG(TASK_SIZE_USER64 - 1)
28 #define USER_DS MAKE_MM_SEG(TASK_SIZE - 1)
31 #define get_ds() (KERNEL_DS)
32 #define get_fs() (current->thread.addr_limit)
34 static inline void set_fs(mm_segment_t fs)
36 current->thread.addr_limit = fs;
37 /* On user-mode return check addr_limit (fs) is correct */
38 set_thread_flag(TIF_FSCHECK);
41 #define segment_eq(a, b) ((a).seg == (b).seg)
43 #define user_addr_max() (get_fs().seg)
47 * This check is sufficient because there is a large enough
48 * gap between user addresses and the kernel addresses
50 #define __access_ok(addr, size, segment) \
51 (((addr) <= (segment).seg) && ((size) <= (segment).seg))
55 static inline int __access_ok(unsigned long addr, unsigned long size,
60 return (size == 0 || size - 1 <= seg.seg - addr);
65 #define access_ok(addr, size) \
66 (__chk_user_ptr(addr), \
67 __access_ok((__force unsigned long)(addr), (size), get_fs()))
70 * These are the main single-value transfer routines. They automatically
71 * use the right size if we just have the right pointer type.
73 * This gets kind of ugly. We want to return _two_ values in "get_user()"
74 * and yet we don't want to do any pointers, because that is too much
75 * of a performance impact. Thus we have a few rather ugly macros here,
76 * and hide all the ugliness from the user.
78 * The "__xxx" versions of the user access functions are versions that
79 * do not verify the address space, that must have been done previously
80 * with a separate "access_ok()" call (this is used when we do multiple
81 * accesses to the same area of user memory).
83 * As we use the same address space for kernel and user data on the
84 * PowerPC, we can just do these as direct assignments. (Of course, the
85 * exception handling means that it's no longer "just"...)
88 #define get_user(x, ptr) \
89 __get_user_check((x), (ptr), sizeof(*(ptr)))
90 #define put_user(x, ptr) \
91 __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
93 #define __get_user(x, ptr) \
94 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
95 #define __put_user(x, ptr) \
96 __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
98 #define __get_user_inatomic(x, ptr) \
99 __get_user_nosleep((x), (ptr), sizeof(*(ptr)))
100 #define __put_user_inatomic(x, ptr) \
101 __put_user_nosleep((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
103 extern long __put_user_bad(void);
106 * We don't tell gcc that we are accessing memory, but this is OK
107 * because we do not write to any memory gcc knows about, so there
108 * are no aliasing issues.
110 #define __put_user_asm(x, addr, err, op) \
111 __asm__ __volatile__( \
112 "1: " op " %1,0(%2) # put_user\n" \
114 ".section .fixup,\"ax\"\n" \
120 : "r" (x), "b" (addr), "i" (-EFAULT), "0" (err))
123 #define __put_user_asm2(x, ptr, retval) \
124 __put_user_asm(x, ptr, retval, "std")
125 #else /* __powerpc64__ */
126 #define __put_user_asm2(x, addr, err) \
127 __asm__ __volatile__( \
128 "1: stw %1,0(%2)\n" \
129 "2: stw %1+1,4(%2)\n" \
131 ".section .fixup,\"ax\"\n" \
138 : "r" (x), "b" (addr), "i" (-EFAULT), "0" (err))
139 #endif /* __powerpc64__ */
141 #define __put_user_size(x, ptr, size, retval) \
145 case 1: __put_user_asm(x, ptr, retval, "stb"); break; \
146 case 2: __put_user_asm(x, ptr, retval, "sth"); break; \
147 case 4: __put_user_asm(x, ptr, retval, "stw"); break; \
148 case 8: __put_user_asm2(x, ptr, retval); break; \
149 default: __put_user_bad(); \
153 #define __put_user_nocheck(x, ptr, size) \
156 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
157 if (!is_kernel_addr((unsigned long)__pu_addr)) \
159 __chk_user_ptr(ptr); \
160 __put_user_size((x), __pu_addr, (size), __pu_err); \
164 #define __put_user_check(x, ptr, size) \
166 long __pu_err = -EFAULT; \
167 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
169 if (access_ok(__pu_addr, size)) \
170 __put_user_size((x), __pu_addr, (size), __pu_err); \
174 #define __put_user_nosleep(x, ptr, size) \
177 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
178 __chk_user_ptr(ptr); \
179 __put_user_size((x), __pu_addr, (size), __pu_err); \
184 extern long __get_user_bad(void);
187 * This does an atomic 128 byte aligned load from userspace.
188 * Upto caller to do enable_kernel_vmx() before calling!
190 #define __get_user_atomic_128_aligned(kaddr, uaddr, err) \
191 __asm__ __volatile__( \
192 "1: lvx 0,0,%1 # get user\n" \
193 " stvx 0,0,%2 # put kernel\n" \
195 ".section .fixup,\"ax\"\n" \
201 : "b" (uaddr), "b" (kaddr), "i" (-EFAULT), "0" (err))
203 #define __get_user_asm(x, addr, err, op) \
204 __asm__ __volatile__( \
205 "1: "op" %1,0(%2) # get_user\n" \
207 ".section .fixup,\"ax\"\n" \
213 : "=r" (err), "=r" (x) \
214 : "b" (addr), "i" (-EFAULT), "0" (err))
217 #define __get_user_asm2(x, addr, err) \
218 __get_user_asm(x, addr, err, "ld")
219 #else /* __powerpc64__ */
220 #define __get_user_asm2(x, addr, err) \
221 __asm__ __volatile__( \
222 "1: lwz %1,0(%2)\n" \
223 "2: lwz %1+1,4(%2)\n" \
225 ".section .fixup,\"ax\"\n" \
233 : "=r" (err), "=&r" (x) \
234 : "b" (addr), "i" (-EFAULT), "0" (err))
235 #endif /* __powerpc64__ */
237 #define __get_user_size(x, ptr, size, retval) \
240 __chk_user_ptr(ptr); \
241 if (size > sizeof(x)) \
242 (x) = __get_user_bad(); \
244 case 1: __get_user_asm(x, ptr, retval, "lbz"); break; \
245 case 2: __get_user_asm(x, ptr, retval, "lhz"); break; \
246 case 4: __get_user_asm(x, ptr, retval, "lwz"); break; \
247 case 8: __get_user_asm2(x, ptr, retval); break; \
248 default: (x) = __get_user_bad(); \
253 * This is a type: either unsigned long, if the argument fits into
254 * that type, or otherwise unsigned long long.
256 #define __long_type(x) \
257 __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
259 #define __get_user_nocheck(x, ptr, size) \
262 __long_type(*(ptr)) __gu_val; \
263 __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
264 __chk_user_ptr(ptr); \
265 if (!is_kernel_addr((unsigned long)__gu_addr)) \
268 __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
269 (x) = (__typeof__(*(ptr)))__gu_val; \
273 #define __get_user_check(x, ptr, size) \
275 long __gu_err = -EFAULT; \
276 __long_type(*(ptr)) __gu_val = 0; \
277 __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
279 if (access_ok(__gu_addr, (size))) { \
281 __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
283 (x) = (__force __typeof__(*(ptr)))__gu_val; \
287 #define __get_user_nosleep(x, ptr, size) \
290 __long_type(*(ptr)) __gu_val; \
291 __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
292 __chk_user_ptr(ptr); \
294 __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
295 (x) = (__force __typeof__(*(ptr)))__gu_val; \
300 /* more complex routines */
302 extern unsigned long __copy_tofrom_user(void __user *to,
303 const void __user *from, unsigned long size);
306 static inline unsigned long
307 raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
309 return __copy_tofrom_user(to, from, n);
311 #endif /* __powerpc64__ */
313 static inline unsigned long raw_copy_from_user(void *to,
314 const void __user *from, unsigned long n)
316 if (__builtin_constant_p(n) && (n <= 8)) {
317 unsigned long ret = 1;
322 __get_user_size(*(u8 *)to, from, 1, ret);
326 __get_user_size(*(u16 *)to, from, 2, ret);
330 __get_user_size(*(u32 *)to, from, 4, ret);
334 __get_user_size(*(u64 *)to, from, 8, ret);
342 return __copy_tofrom_user((__force void __user *)to, from, n);
345 static inline unsigned long raw_copy_to_user(void __user *to,
346 const void *from, unsigned long n)
348 if (__builtin_constant_p(n) && (n <= 8)) {
349 unsigned long ret = 1;
353 __put_user_size(*(u8 *)from, (u8 __user *)to, 1, ret);
356 __put_user_size(*(u16 *)from, (u16 __user *)to, 2, ret);
359 __put_user_size(*(u32 *)from, (u32 __user *)to, 4, ret);
362 __put_user_size(*(u64 *)from, (u64 __user *)to, 8, ret);
369 return __copy_tofrom_user(to, (__force const void __user *)from, n);
372 extern unsigned long __clear_user(void __user *addr, unsigned long size);
374 static inline unsigned long clear_user(void __user *addr, unsigned long size)
377 if (likely(access_ok(addr, size)))
378 return __clear_user(addr, size);
382 extern long strncpy_from_user(char *dst, const char __user *src, long count);
383 extern __must_check long strnlen_user(const char __user *str, long n);
385 extern long __copy_from_user_flushcache(void *dst, const void __user *src,
387 extern void memcpy_page_flushcache(char *to, struct page *page, size_t offset,
390 #endif /* _ARCH_POWERPC_UACCESS_H */