1 #ifndef __PARISC_UACCESS_H
2 #define __PARISC_UACCESS_H
5 * User space memory access functions
10 #include <asm-generic/uaccess-unaligned.h>
12 #include <linux/bug.h>
13 #include <linux/string.h>
16 #define VERIFY_WRITE 1
18 #define KERNEL_DS ((mm_segment_t){0})
19 #define USER_DS ((mm_segment_t){1})
21 #define segment_eq(a, b) ((a).seg == (b).seg)
23 #define get_ds() (KERNEL_DS)
24 #define get_fs() (current_thread_info()->addr_limit)
25 #define set_fs(x) (current_thread_info()->addr_limit = (x))
28 * Note that since kernel addresses are in a separate address space on
29 * parisc, we don't need to do anything for access_ok().
30 * We just let the page fault handler do the right thing. This also means
31 * that put_user is the same as __put_user, etc.
34 static inline long access_ok(int type, const void __user * addr,
40 #define put_user __put_user
41 #define get_user __get_user
43 #if !defined(CONFIG_64BIT)
44 #define LDD_KERNEL(ptr) BUILD_BUG()
45 #define LDD_USER(ptr) BUILD_BUG()
46 #define STD_KERNEL(x, ptr) __put_kernel_asm64(x, ptr)
47 #define STD_USER(x, ptr) __put_user_asm64(x, ptr)
48 #define ASM_WORD_INSN ".word\t"
50 #define LDD_KERNEL(ptr) __get_kernel_asm("ldd", ptr)
51 #define LDD_USER(ptr) __get_user_asm("ldd", ptr)
52 #define STD_KERNEL(x, ptr) __put_kernel_asm("std", x, ptr)
53 #define STD_USER(x, ptr) __put_user_asm("std", x, ptr)
54 #define ASM_WORD_INSN ".dword\t"
58 * The exception table contains two values: the first is an address
59 * for an instruction that is allowed to fault, and the second is
60 * the address to the fixup routine. Even on a 64bit kernel we could
61 * use a 32bit (unsigned int) address here.
64 #define ARCH_HAS_RELATIVE_EXTABLE
65 struct exception_table_entry {
66 int insn; /* relative address of insn that is allowed to fault. */
67 int fixup; /* relative address of fixup routine */
70 #define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
71 ".section __ex_table,\"aw\"\n" \
72 ".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \
76 * The page fault handler stores, in a per-cpu area, the following information
77 * if a fixup routine is available.
79 struct exception_data {
80 unsigned long fault_ip;
81 unsigned long fault_gp;
82 unsigned long fault_space;
83 unsigned long fault_addr;
86 #define __get_user(x, ptr) \
88 register long __gu_err __asm__ ("r8") = 0; \
89 register long __gu_val __asm__ ("r9") = 0; \
91 if (segment_eq(get_fs(), KERNEL_DS)) { \
92 switch (sizeof(*(ptr))) { \
93 case 1: __get_kernel_asm("ldb", ptr); break; \
94 case 2: __get_kernel_asm("ldh", ptr); break; \
95 case 4: __get_kernel_asm("ldw", ptr); break; \
96 case 8: LDD_KERNEL(ptr); break; \
97 default: BUILD_BUG(); break; \
101 switch (sizeof(*(ptr))) { \
102 case 1: __get_user_asm("ldb", ptr); break; \
103 case 2: __get_user_asm("ldh", ptr); break; \
104 case 4: __get_user_asm("ldw", ptr); break; \
105 case 8: LDD_USER(ptr); break; \
106 default: BUILD_BUG(); break; \
110 (x) = (__force __typeof__(*(ptr))) __gu_val; \
114 #define __get_kernel_asm(ldx, ptr) \
115 __asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \
116 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
117 : "=r"(__gu_val), "=r"(__gu_err) \
118 : "r"(ptr), "1"(__gu_err) \
121 #define __get_user_asm(ldx, ptr) \
122 __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \
123 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
124 : "=r"(__gu_val), "=r"(__gu_err) \
125 : "r"(ptr), "1"(__gu_err) \
128 #define __put_user(x, ptr) \
130 register long __pu_err __asm__ ("r8") = 0; \
131 __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \
133 if (segment_eq(get_fs(), KERNEL_DS)) { \
134 switch (sizeof(*(ptr))) { \
135 case 1: __put_kernel_asm("stb", __x, ptr); break; \
136 case 2: __put_kernel_asm("sth", __x, ptr); break; \
137 case 4: __put_kernel_asm("stw", __x, ptr); break; \
138 case 8: STD_KERNEL(__x, ptr); break; \
139 default: BUILD_BUG(); break; \
143 switch (sizeof(*(ptr))) { \
144 case 1: __put_user_asm("stb", __x, ptr); break; \
145 case 2: __put_user_asm("sth", __x, ptr); break; \
146 case 4: __put_user_asm("stw", __x, ptr); break; \
147 case 8: STD_USER(__x, ptr); break; \
148 default: BUILD_BUG(); break; \
156 * The "__put_user/kernel_asm()" macros tell gcc they read from memory
157 * instead of writing. This is because they do not write to any memory
158 * gcc knows about, so there are no aliasing issues. These macros must
159 * also be aware that "fixup_put_user_skip_[12]" are executed in the
160 * context of the fault, and any registers used there must be listed
161 * as clobbers. In this case only "r1" is used by the current routines.
162 * r8/r9 are already listed as err/val.
165 #define __put_kernel_asm(stx, x, ptr) \
166 __asm__ __volatile__ ( \
167 "\n1:\t" stx "\t%2,0(%1)\n\t" \
168 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
170 : "r"(ptr), "r"(x), "0"(__pu_err) \
173 #define __put_user_asm(stx, x, ptr) \
174 __asm__ __volatile__ ( \
175 "\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \
176 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
178 : "r"(ptr), "r"(x), "0"(__pu_err) \
182 #if !defined(CONFIG_64BIT)
184 #define __put_kernel_asm64(__val, ptr) do { \
185 __asm__ __volatile__ ( \
186 "\n1:\tstw %2,0(%1)" \
187 "\n2:\tstw %R2,4(%1)\n\t" \
188 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
189 ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
191 : "r"(ptr), "r"(__val), "0"(__pu_err) \
195 #define __put_user_asm64(__val, ptr) do { \
196 __asm__ __volatile__ ( \
197 "\n1:\tstw %2,0(%%sr3,%1)" \
198 "\n2:\tstw %R2,4(%%sr3,%1)\n\t" \
199 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
200 ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
202 : "r"(ptr), "r"(__val), "0"(__pu_err) \
206 #endif /* !defined(CONFIG_64BIT) */
210 * Complex access routines -- external declarations
213 extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
214 extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
215 extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
216 extern long strncpy_from_user(char *, const char __user *, long);
217 extern unsigned lclear_user(void __user *, unsigned long);
218 extern long lstrnlen_user(const char __user *, long);
220 * Complex access routines -- macros
222 #define user_addr_max() (~0UL)
224 #define strnlen_user lstrnlen_user
225 #define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
226 #define clear_user lclear_user
227 #define __clear_user lclear_user
229 unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len);
230 #define __copy_to_user copy_to_user
231 unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len);
232 unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len);
233 #define __copy_in_user copy_in_user
234 #define __copy_to_user_inatomic __copy_to_user
235 #define __copy_from_user_inatomic __copy_from_user
237 extern void copy_from_user_overflow(void)
238 #ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
239 __compiletime_error("copy_from_user() buffer size is not provably correct")
241 __compiletime_warning("copy_from_user() buffer size is not provably correct")
245 static inline unsigned long __must_check copy_from_user(void *to,
246 const void __user *from,
249 int sz = __compiletime_object_size(to);
250 unsigned long ret = n;
252 if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n))
253 ret = __copy_from_user(to, from, n);
255 copy_from_user_overflow();
257 memset(to + (n - ret), 0, ret);
262 int fixup_exception(struct pt_regs *regs);
264 #endif /* __PARISC_UACCESS_H */