1 #ifndef __PARISC_UACCESS_H
2 #define __PARISC_UACCESS_H
5 * User space memory access functions
7 #include <asm/processor.h>
10 #include <asm/errno.h>
11 #include <asm-generic/uaccess-unaligned.h>
13 #include <linux/sched.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 extern int __get_kernel_bad(void);
35 extern int __get_user_bad(void);
36 extern int __put_kernel_bad(void);
37 extern int __put_user_bad(void);
41 * Test whether a block of memory is a valid user space address.
42 * Returns 0 if the range is valid, nonzero otherwise.
44 static inline int __range_not_ok(unsigned long addr, unsigned long size,
47 unsigned long __newaddr = addr + size;
48 return (__newaddr < addr || __newaddr > limit || size > limit);
52 * access_ok: - Checks if a user space pointer is valid
53 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
54 * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
55 * to write to a block, it is always safe to read from it.
56 * @addr: User space pointer to start of block to check
57 * @size: Size of block to check
59 * Context: User context only. This function may sleep.
61 * Checks if a pointer to a block of memory in user space is valid.
63 * Returns true (nonzero) if the memory block may be valid, false (zero)
64 * if it is definitely invalid.
66 * Note that, depending on architecture, this function probably just
67 * checks that the pointer is in the user space range - after calling
68 * this function, memory access functions may still return -EFAULT.
70 #define access_ok(type, addr, size) \
71 ( __chk_user_ptr(addr), \
72 !__range_not_ok((unsigned long) (__force void *) (addr), \
73 size, user_addr_max()) \
76 #define put_user __put_user
77 #define get_user __get_user
79 #if !defined(CONFIG_64BIT)
80 #define LDD_KERNEL(ptr) __get_kernel_bad();
81 #define LDD_USER(ptr) __get_user_bad();
82 #define STD_KERNEL(x, ptr) __put_kernel_asm64(x,ptr)
83 #define STD_USER(x, ptr) __put_user_asm64(x,ptr)
84 #define ASM_WORD_INSN ".word\t"
86 #define LDD_KERNEL(ptr) __get_kernel_asm("ldd",ptr)
87 #define LDD_USER(ptr) __get_user_asm("ldd",ptr)
88 #define STD_KERNEL(x, ptr) __put_kernel_asm("std",x,ptr)
89 #define STD_USER(x, ptr) __put_user_asm("std",x,ptr)
90 #define ASM_WORD_INSN ".dword\t"
94 * The exception table contains two values: the first is an address
95 * for an instruction that is allowed to fault, and the second is
96 * the address to the fixup routine. Even on a 64bit kernel we could
97 * use a 32bit (unsigned int) address here.
100 struct exception_table_entry {
101 unsigned long insn; /* address of insn that is allowed to fault. */
102 unsigned long fixup; /* fixup routine */
105 #define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
106 ".section __ex_table,\"aw\"\n" \
107 ASM_WORD_INSN #fault_addr ", " #except_addr "\n\t" \
111 * The page fault handler stores, in a per-cpu area, the following information
112 * if a fixup routine is available.
114 struct exception_data {
115 unsigned long fault_ip;
116 unsigned long fault_space;
117 unsigned long fault_addr;
120 #define __get_user(x,ptr) \
122 register long __gu_err __asm__ ("r8") = 0; \
123 register long __gu_val __asm__ ("r9") = 0; \
125 if (segment_eq(get_fs(),KERNEL_DS)) { \
126 switch (sizeof(*(ptr))) { \
127 case 1: __get_kernel_asm("ldb",ptr); break; \
128 case 2: __get_kernel_asm("ldh",ptr); break; \
129 case 4: __get_kernel_asm("ldw",ptr); break; \
130 case 8: LDD_KERNEL(ptr); break; \
131 default: __get_kernel_bad(); break; \
135 switch (sizeof(*(ptr))) { \
136 case 1: __get_user_asm("ldb",ptr); break; \
137 case 2: __get_user_asm("ldh",ptr); break; \
138 case 4: __get_user_asm("ldw",ptr); break; \
139 case 8: LDD_USER(ptr); break; \
140 default: __get_user_bad(); break; \
144 (x) = (__typeof__(*(ptr))) __gu_val; \
148 #define __get_kernel_asm(ldx,ptr) \
149 __asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \
150 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
151 : "=r"(__gu_val), "=r"(__gu_err) \
152 : "r"(ptr), "1"(__gu_err) \
155 #define __get_user_asm(ldx,ptr) \
156 __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \
157 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_get_user_skip_1)\
158 : "=r"(__gu_val), "=r"(__gu_err) \
159 : "r"(ptr), "1"(__gu_err) \
162 #define __put_user(x,ptr) \
164 register long __pu_err __asm__ ("r8") = 0; \
165 __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \
167 if (segment_eq(get_fs(),KERNEL_DS)) { \
168 switch (sizeof(*(ptr))) { \
169 case 1: __put_kernel_asm("stb",__x,ptr); break; \
170 case 2: __put_kernel_asm("sth",__x,ptr); break; \
171 case 4: __put_kernel_asm("stw",__x,ptr); break; \
172 case 8: STD_KERNEL(__x,ptr); break; \
173 default: __put_kernel_bad(); break; \
177 switch (sizeof(*(ptr))) { \
178 case 1: __put_user_asm("stb",__x,ptr); break; \
179 case 2: __put_user_asm("sth",__x,ptr); break; \
180 case 4: __put_user_asm("stw",__x,ptr); break; \
181 case 8: STD_USER(__x,ptr); break; \
182 default: __put_user_bad(); break; \
190 * The "__put_user/kernel_asm()" macros tell gcc they read from memory
191 * instead of writing. This is because they do not write to any memory
192 * gcc knows about, so there are no aliasing issues. These macros must
193 * also be aware that "fixup_put_user_skip_[12]" are executed in the
194 * context of the fault, and any registers used there must be listed
195 * as clobbers. In this case only "r1" is used by the current routines.
196 * r8/r9 are already listed as err/val.
199 #define __put_kernel_asm(stx,x,ptr) \
200 __asm__ __volatile__ ( \
201 "\n1:\t" stx "\t%2,0(%1)\n\t" \
202 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\
204 : "r"(ptr), "r"(x), "0"(__pu_err) \
207 #define __put_user_asm(stx,x,ptr) \
208 __asm__ __volatile__ ( \
209 "\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \
210 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\
212 : "r"(ptr), "r"(x), "0"(__pu_err) \
216 #if !defined(CONFIG_64BIT)
218 #define __put_kernel_asm64(__val,ptr) do { \
219 __asm__ __volatile__ ( \
220 "\n1:\tstw %2,0(%1)" \
221 "\n2:\tstw %R2,4(%1)\n\t" \
222 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\
223 ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\
225 : "r"(ptr), "r"(__val), "0"(__pu_err) \
229 #define __put_user_asm64(__val,ptr) do { \
230 __asm__ __volatile__ ( \
231 "\n1:\tstw %2,0(%%sr3,%1)" \
232 "\n2:\tstw %R2,4(%%sr3,%1)\n\t" \
233 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\
234 ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\
236 : "r"(ptr), "r"(__val), "0"(__pu_err) \
240 #endif /* !defined(CONFIG_64BIT) */
244 * Complex access routines -- external declarations
247 extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
248 extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
249 extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
250 extern long strncpy_from_user(char *, const char __user *, long);
251 extern unsigned lclear_user(void __user *,unsigned long);
252 extern long lstrnlen_user(const char __user *,long);
254 * Complex access routines -- macros
257 #define user_addr_max() (TASK_SIZE)
259 #define user_addr_max() (DEFAULT_TASK_SIZE)
262 #define strnlen_user lstrnlen_user
263 #define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
264 #define clear_user lclear_user
265 #define __clear_user lclear_user
267 unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len);
268 #define __copy_to_user copy_to_user
269 unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len);
270 unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len);
271 #define __copy_in_user copy_in_user
272 #define __copy_to_user_inatomic __copy_to_user
273 #define __copy_from_user_inatomic __copy_from_user
275 extern void copy_from_user_overflow(void)
276 #ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
277 __compiletime_error("copy_from_user() buffer size is not provably correct")
279 __compiletime_warning("copy_from_user() buffer size is not provably correct")
283 static inline unsigned long __must_check copy_from_user(void *to,
284 const void __user *from,
287 int sz = __compiletime_object_size(to);
290 if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n))
291 ret = __copy_from_user(to, from, n);
293 copy_from_user_overflow();
299 int fixup_exception(struct pt_regs *regs);
301 #endif /* __PARISC_UACCESS_H */