1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
|
#ifndef __PARISC_UACCESS_H
#define __PARISC_UACCESS_H
/*
* User space memory access functions
*/
#include <asm/page.h>
#include <asm/cache.h>
#include <asm/errno.h>
#include <asm-generic/uaccess-unaligned.h>
#include <linux/bug.h>
#define VERIFY_READ 0
#define VERIFY_WRITE 1
#define KERNEL_DS ((mm_segment_t){0})
#define USER_DS ((mm_segment_t){1})
#define segment_eq(a, b) ((a).seg == (b).seg)
#define get_ds() (KERNEL_DS)
#define get_fs() (current_thread_info()->addr_limit)
#define set_fs(x) (current_thread_info()->addr_limit = (x))
/*
* Note that since kernel addresses are in a separate address space on
* parisc, we don't need to do anything for access_ok().
* We just let the page fault handler do the right thing. This also means
* that put_user is the same as __put_user, etc.
*/
static inline long access_ok(int type, const void __user * addr,
unsigned long size)
{
return 1;
}
#define put_user __put_user
#define get_user __get_user
#if !defined(CONFIG_64BIT)
#define LDD_USER(ptr) __get_user_asm64(ptr)
#define STD_USER(x, ptr) __put_user_asm64(x, ptr)
#else
#define LDD_USER(ptr) __get_user_asm("ldd", ptr)
#define STD_USER(x, ptr) __put_user_asm("std", x, ptr)
#endif
/*
* The exception table contains two values: the first is the relative offset to
* the address of the instruction that is allowed to fault, and the second is
* the relative offset to the address of the fixup routine. Since relative
* addresses are used, 32bit values are sufficient even on 64bit kernel.
*/
#define ARCH_HAS_RELATIVE_EXTABLE
struct exception_table_entry {
int insn; /* relative address of insn that is allowed to fault. */
int fixup; /* relative address of fixup routine */
};
#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
".section __ex_table,\"aw\"\n" \
".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \
".previous\n"
/*
* The page fault handler stores, in a per-cpu area, the following information
* if a fixup routine is available.
*/
struct exception_data {
unsigned long fault_ip;
unsigned long fault_gp;
unsigned long fault_space;
unsigned long fault_addr;
};
/*
* load_sr2() preloads the space register %%sr2 - based on the value of
* get_fs() - with either a value of 0 to access kernel space (KERNEL_DS which
* is 0), or with the current value of %%sr3 to access user space (USER_DS)
* memory. The following __get_user_asm() and __put_user_asm() functions have
* %%sr2 hard-coded to access the requested memory.
*/
#define load_sr2() \
__asm__(" or,= %0,%%r0,%%r0\n\t" \
" mfsp %%sr3,%0\n\t" \
" mtsp %0,%%sr2\n\t" \
: : "r"(get_fs()) : )
#define __get_user(x, ptr) \
({ \
register long __gu_err __asm__ ("r8") = 0; \
register long __gu_val __asm__ ("r9") = 0; \
\
load_sr2(); \
switch (sizeof(*(ptr))) { \
case 1: __get_user_asm("ldb", ptr); break; \
case 2: __get_user_asm("ldh", ptr); break; \
case 4: __get_user_asm("ldw", ptr); break; \
case 8: LDD_USER(ptr); break; \
default: BUILD_BUG(); break; \
} \
\
(x) = (__force __typeof__(*(ptr))) __gu_val; \
__gu_err; \
})
#define __get_user_asm(ldx, ptr) \
__asm__("\n1:\t" ldx "\t0(%%sr2,%2),%0\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err) \
: "r1");
#if !defined(CONFIG_64BIT)
#define __get_user_asm64(ptr) \
__asm__("\n1:\tldw 0(%%sr2,%2),%0" \
"\n2:\tldw 4(%%sr2,%2),%R0\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_2)\
ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_get_user_skip_1)\
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err) \
: "r1");
#endif /* !defined(CONFIG_64BIT) */
#define __put_user(x, ptr) \
({ \
register long __pu_err __asm__ ("r8") = 0; \
__typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \
\
load_sr2(); \
switch (sizeof(*(ptr))) { \
case 1: __put_user_asm("stb", __x, ptr); break; \
case 2: __put_user_asm("sth", __x, ptr); break; \
case 4: __put_user_asm("stw", __x, ptr); break; \
case 8: STD_USER(__x, ptr); break; \
default: BUILD_BUG(); break; \
} \
\
__pu_err; \
})
/*
* The "__put_user/kernel_asm()" macros tell gcc they read from memory
* instead of writing. This is because they do not write to any memory
* gcc knows about, so there are no aliasing issues. These macros must
* also be aware that "fixup_put_user_skip_[12]" are executed in the
* context of the fault, and any registers used there must be listed
* as clobbers. In this case only "r1" is used by the current routines.
* r8/r9 are already listed as err/val.
*/
#define __put_user_asm(stx, x, ptr) \
__asm__ __volatile__ ( \
"\n1:\t" stx "\t%2,0(%%sr2,%1)\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err) \
: "r1")
#if !defined(CONFIG_64BIT)
#define __put_user_asm64(__val, ptr) do { \
__asm__ __volatile__ ( \
"\n1:\tstw %2,0(%%sr2,%1)" \
"\n2:\tstw %R2,4(%%sr2,%1)\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
: "=r"(__pu_err) \
: "r"(ptr), "r"(__val), "0"(__pu_err) \
: "r1"); \
} while (0)
#endif /* !defined(CONFIG_64BIT) */
/*
* Complex access routines -- external declarations
*/
extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
extern long strncpy_from_user(char *, const char __user *, long);
extern unsigned lclear_user(void __user *, unsigned long);
extern long lstrnlen_user(const char __user *, long);
/*
* Complex access routines -- macros
*/
#define user_addr_max() (~0UL)
#define strnlen_user lstrnlen_user
#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
#define clear_user lclear_user
#define __clear_user lclear_user
unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len);
#define __copy_to_user copy_to_user
unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len);
unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len);
#define __copy_in_user copy_in_user
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
extern void __compiletime_error("usercopy buffer size is too small")
__bad_copy_user(void);
static inline void copy_user_overflow(int size, unsigned long count)
{
WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
}
static inline unsigned long __must_check copy_from_user(void *to,
const void __user *from,
unsigned long n)
{
int sz = __compiletime_object_size(to);
int ret = -EFAULT;
if (likely(sz == -1 || sz >= n))
ret = __copy_from_user(to, from, n);
else if (!__builtin_constant_p(n))
copy_user_overflow(sz, n);
else
__bad_copy_user();
return ret;
}
struct pt_regs;
int fixup_exception(struct pt_regs *regs);
#endif /* __PARISC_UACCESS_H */
|
