xref: /openbmc/linux/arch/sh/include/asm/uaccess.h (revision a2818ee4)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_SH_UACCESS_H
3 #define __ASM_SH_UACCESS_H
4 
5 #include <asm/segment.h>
6 #include <asm/extable.h>
7 
8 #define __addr_ok(addr) \
9 	((unsigned long __force)(addr) < current_thread_info()->addr_limit.seg)
10 
11 /*
12  * __access_ok: Check if address with size is OK or not.
13  *
14  * Uhhuh, this needs 33-bit arithmetic. We have a carry..
15  *
16  * sum := addr + size;  carry? --> flag = true;
17  * if (sum >= addr_limit) flag = true;
18  */
19 #define __access_ok(addr, size)		\
20 	(__addr_ok((addr) + (size)))
21 #define access_ok(addr, size)	\
22 	(__chk_user_ptr(addr),		\
23 	 __access_ok((unsigned long __force)(addr), (size)))
24 
25 #define user_addr_max()	(current_thread_info()->addr_limit.seg)
26 
27 /*
28  * Uh, these should become the main single-value transfer routines ...
29  * They automatically use the right size if we just have the right
30  * pointer type ...
31  *
32  * As SuperH uses the same address space for kernel and user data, we
33  * can just do these as direct assignments.
34  *
35  * Careful to not
36  * (a) re-use the arguments for side effects (sizeof is ok)
37  * (b) require any knowledge of processes at this stage
38  */
39 #define put_user(x,ptr)		__put_user_check((x), (ptr), sizeof(*(ptr)))
40 #define get_user(x,ptr)		__get_user_check((x), (ptr), sizeof(*(ptr)))
41 
42 /*
43  * The "__xxx" versions do not do address space checking, useful when
44  * doing multiple accesses to the same area (the user has to do the
45  * checks by hand with "access_ok()")
46  */
47 #define __put_user(x,ptr)	__put_user_nocheck((x), (ptr), sizeof(*(ptr)))
48 #define __get_user(x,ptr)	__get_user_nocheck((x), (ptr), sizeof(*(ptr)))
49 
50 struct __large_struct { unsigned long buf[100]; };
51 #define __m(x) (*(struct __large_struct __user *)(x))
52 
53 #define __get_user_nocheck(x,ptr,size)				\
54 ({								\
55 	long __gu_err;						\
56 	unsigned long __gu_val;					\
57 	const __typeof__(*(ptr)) __user *__gu_addr = (ptr);	\
58 	__chk_user_ptr(ptr);					\
59 	__get_user_size(__gu_val, __gu_addr, (size), __gu_err);	\
60 	(x) = (__force __typeof__(*(ptr)))__gu_val;		\
61 	__gu_err;						\
62 })
63 
64 #define __get_user_check(x,ptr,size)					\
65 ({									\
66 	long __gu_err = -EFAULT;					\
67 	unsigned long __gu_val = 0;					\
68 	const __typeof__(*(ptr)) *__gu_addr = (ptr);			\
69 	if (likely(access_ok(__gu_addr, (size))))		\
70 		__get_user_size(__gu_val, __gu_addr, (size), __gu_err);	\
71 	(x) = (__force __typeof__(*(ptr)))__gu_val;			\
72 	__gu_err;							\
73 })
74 
75 #define __put_user_nocheck(x,ptr,size)				\
76 ({								\
77 	long __pu_err;						\
78 	__typeof__(*(ptr)) __user *__pu_addr = (ptr);		\
79 	__typeof__(*(ptr)) __pu_val = x;			\
80 	__chk_user_ptr(ptr);					\
81 	__put_user_size(__pu_val, __pu_addr, (size), __pu_err);	\
82 	__pu_err;						\
83 })
84 
85 #define __put_user_check(x,ptr,size)				\
86 ({								\
87 	long __pu_err = -EFAULT;				\
88 	__typeof__(*(ptr)) __user *__pu_addr = (ptr);		\
89 	__typeof__(*(ptr)) __pu_val = x;			\
90 	if (likely(access_ok(__pu_addr, size)))	\
91 		__put_user_size(__pu_val, __pu_addr, (size),	\
92 				__pu_err);			\
93 	__pu_err;						\
94 })
95 
96 #ifdef CONFIG_SUPERH32
97 # include <asm/uaccess_32.h>
98 #else
99 # include <asm/uaccess_64.h>
100 #endif
101 
102 extern long strncpy_from_user(char *dest, const char __user *src, long count);
103 
104 extern __must_check long strnlen_user(const char __user *str, long n);
105 
106 /* Generic arbitrary sized copy.  */
107 /* Return the number of bytes NOT copied */
108 __kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n);
109 
110 static __always_inline unsigned long
111 raw_copy_from_user(void *to, const void __user *from, unsigned long n)
112 {
113 	return __copy_user(to, (__force void *)from, n);
114 }
115 
116 static __always_inline unsigned long __must_check
117 raw_copy_to_user(void __user *to, const void *from, unsigned long n)
118 {
119 	return __copy_user((__force void *)to, from, n);
120 }
121 #define INLINE_COPY_FROM_USER
122 #define INLINE_COPY_TO_USER
123 
124 /*
125  * Clear the area and return remaining number of bytes
126  * (on failure.  Usually it's 0.)
127  */
128 __kernel_size_t __clear_user(void *addr, __kernel_size_t size);
129 
130 #define clear_user(addr,n)						\
131 ({									\
132 	void __user * __cl_addr = (addr);				\
133 	unsigned long __cl_size = (n);					\
134 									\
135 	if (__cl_size && access_ok(__cl_addr, __cl_size))		\
136 		__cl_size = __clear_user(__cl_addr, __cl_size);		\
137 									\
138 	__cl_size;							\
139 })
140 
141 extern void *set_exception_table_vec(unsigned int vec, void *handler);
142 
143 static inline void *set_exception_table_evt(unsigned int evt, void *handler)
144 {
145 	return set_exception_table_vec(evt >> 5, handler);
146 }
147 
148 struct mem_access {
149 	unsigned long (*from)(void *dst, const void __user *src, unsigned long cnt);
150 	unsigned long (*to)(void __user *dst, const void *src, unsigned long cnt);
151 };
152 
153 int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs,
154 			    struct mem_access *ma, int, unsigned long address);
155 
156 #endif /* __ASM_SH_UACCESS_H */
157