xref: /linux/arch/parisc/include/asm/uaccess.h (revision 0905809b38bda1fa0b206986c44d846e46f13c1d)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __PARISC_UACCESS_H
3 #define __PARISC_UACCESS_H
4 
5 /*
6  * User space memory access functions
7  */
8 #include <asm/page.h>
9 #include <asm/cache.h>
10 #include <asm/extable.h>
11 
12 #include <linux/bug.h>
13 #include <linux/string.h>
14 
15 #define TASK_SIZE_MAX DEFAULT_TASK_SIZE
16 #include <asm/pgtable.h>
17 #include <asm-generic/access_ok.h>
18 
19 #define put_user __put_user
20 #define get_user __get_user
21 
22 #if !defined(CONFIG_64BIT)
23 #define LDD_USER(sr, val, ptr)	__get_user_asm64(sr, val, ptr)
24 #define STD_USER(sr, x, ptr)	__put_user_asm64(sr, x, ptr)
25 #else
26 #define LDD_USER(sr, val, ptr)	__get_user_asm(sr, val, "ldd", ptr)
27 #define STD_USER(sr, x, ptr)	__put_user_asm(sr, "std", x, ptr)
28 #endif
29 
30 #define __get_user_internal(sr, val, ptr)		\
31 ({							\
32 	ASM_EXCEPTIONTABLE_VAR(__gu_err);		\
33 							\
34 	switch (sizeof(*(ptr))) {			\
35 	case 1: __get_user_asm(sr, val, "ldb", ptr); break; \
36 	case 2: __get_user_asm(sr, val, "ldh", ptr); break; \
37 	case 4: __get_user_asm(sr, val, "ldw", ptr); break; \
38 	case 8: LDD_USER(sr, val, ptr); break;		\
39 	default: BUILD_BUG();				\
40 	}						\
41 							\
42 	__gu_err;					\
43 })
44 
45 #define __probe_user_internal(sr, error, ptr)			\
46 ({								\
47 	__asm__("\tproberi (%%sr%1,%2),%3,%0\n"			\
48 		"\tcmpiclr,= 1,%0,%0\n"				\
49 		"\tldi %4,%0\n"					\
50 		: "=r"(error)					\
51 		: "i"(sr), "r"(ptr), "i"(PRIV_USER),		\
52 		  "i"(-EFAULT));				\
53 })
54 
55 #define __get_user(val, ptr)					\
56 ({								\
57 	register long __gu_err;					\
58 								\
59 	__gu_err = __get_user_internal(SR_USER, val, ptr);	\
60 	if (likely(!__gu_err))					\
61 		__probe_user_internal(SR_USER, __gu_err, ptr);	\
62 	__gu_err;						\
63 })
64 
65 #define __get_user_asm(sr, val, ldx, ptr)		\
66 {							\
67 	register long __gu_val;				\
68 							\
69 	__asm__("1: " ldx " 0(%%sr%2,%3),%0\n"		\
70 		"9:\n"					\
71 		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b, "%1")	\
72 		: "=r"(__gu_val), "+r"(__gu_err)        \
73 		: "i"(sr), "r"(ptr));			\
74 							\
75 	(val) = (__force __typeof__(*(ptr))) __gu_val;	\
76 }
77 
78 #define __get_kernel_nofault(dst, src, type, err_label)	\
79 {							\
80 	type __z;					\
81 	long __err;					\
82 	__err = __get_user_internal(SR_KERNEL, __z, (type *)(src)); \
83 	if (unlikely(__err))				\
84 		goto err_label;				\
85 	else						\
86 		*(type *)(dst) = __z;			\
87 }
88 
89 
90 #if !defined(CONFIG_64BIT)
91 
92 #define __get_user_asm64(sr, val, ptr)			\
93 {							\
94 	union {						\
95 		unsigned long long	l;		\
96 		__typeof__(*(ptr))	t;		\
97 	} __gu_tmp;					\
98 							\
99 	__asm__("   copy %%r0,%R0\n"			\
100 		"1: ldw 0(%%sr%2,%3),%0\n"		\
101 		"2: ldw 4(%%sr%2,%3),%R0\n"		\
102 		"9:\n"					\
103 		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b, "%1")	\
104 		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b, "%1")	\
105 		: "=&r"(__gu_tmp.l), "+r"(__gu_err)	\
106 		: "i"(sr), "r"(ptr));			\
107 							\
108 	(val) = __gu_tmp.t;				\
109 }
110 
111 #endif /* !defined(CONFIG_64BIT) */
112 
113 
114 #define __put_user_internal(sr, x, ptr)				\
115 ({								\
116 	ASM_EXCEPTIONTABLE_VAR(__pu_err);		      	\
117 								\
118 	switch (sizeof(*(ptr))) {				\
119 	case 1: __put_user_asm(sr, "stb", x, ptr); break;	\
120 	case 2: __put_user_asm(sr, "sth", x, ptr); break;	\
121 	case 4: __put_user_asm(sr, "stw", x, ptr); break;	\
122 	case 8: STD_USER(sr, x, ptr); break;			\
123 	default: BUILD_BUG();					\
124 	}							\
125 								\
126 	__pu_err;						\
127 })
128 
129 #define __put_user(x, ptr)					\
130 ({								\
131 	__typeof__(&*(ptr)) __ptr = ptr;			\
132 	__typeof__(*(__ptr)) __x = (__typeof__(*(__ptr)))(x);	\
133 	__put_user_internal(SR_USER, __x, __ptr);		\
134 })
135 
136 #define __put_kernel_nofault(dst, src, type, err_label)		\
137 {								\
138 	type __z = *(type *)(src);				\
139 	long __err;						\
140 	__err = __put_user_internal(SR_KERNEL, __z, (type *)(dst)); \
141 	if (unlikely(__err))					\
142 		goto err_label;					\
143 }
144 
145 
146 
147 
148 /*
149  * The "__put_user/kernel_asm()" macros tell gcc they read from memory
150  * instead of writing. This is because they do not write to any memory
151  * gcc knows about, so there are no aliasing issues. These macros must
152  * also be aware that fixups are executed in the context of the fault,
153  * and any registers used there must be listed as clobbers.
154  * The register holding the possible EFAULT error (ASM_EXCEPTIONTABLE_REG)
155  * is already listed as input and output register.
156  */
157 
158 #define __put_user_asm(sr, stx, x, ptr)				\
159 	__asm__ __volatile__ (					\
160 		"1: " stx " %1,0(%%sr%2,%3)\n"			\
161 		"9:\n"						\
162 		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b, "%0")	\
163 		: "+r"(__pu_err)				\
164 		: "r"(x), "i"(sr), "r"(ptr))
165 
166 
167 #if !defined(CONFIG_64BIT)
168 
169 #define __put_user_asm64(sr, __val, ptr) do {			\
170 	__asm__ __volatile__ (					\
171 		"1: stw %1,0(%%sr%2,%3)\n"			\
172 		"2: stw %R1,4(%%sr%2,%3)\n"			\
173 		"9:\n"						\
174 		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b, "%0")	\
175 		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b, "%0")	\
176 		: "+r"(__pu_err)				\
177 		: "r"(__val), "i"(sr), "r"(ptr));		\
178 } while (0)
179 
180 #endif /* !defined(CONFIG_64BIT) */
181 
182 /*
183  * Complex access routines -- external declarations
184  */
185 
186 extern long strncpy_from_user(char *, const char __user *, long);
187 extern __must_check unsigned lclear_user(void __user *, unsigned long);
188 extern __must_check long strnlen_user(const char __user *src, long n);
189 /*
190  * Complex access routines -- macros
191  */
192 
193 #define clear_user lclear_user
194 #define __clear_user lclear_user
195 
196 unsigned long __must_check raw_copy_to_user(void __user *dst, const void *src,
197 					    unsigned long len);
198 unsigned long __must_check raw_copy_from_user(void *dst, const void __user *src,
199 					    unsigned long len);
200 #define INLINE_COPY_TO_USER
201 #define INLINE_COPY_FROM_USER
202 
203 #endif /* __PARISC_UACCESS_H */
204