1#ifndef _ASM_UACCESS_H
2#define _ASM_UACCESS_H
3
4/*
5 * User space memory access functions
6 */
7
8#ifdef __KERNEL__
9#include <linux/errno.h>
10#include <linux/compiler.h>
11#include <linux/string.h>
12#include <linux/thread_info.h>
13#include <asm/asi.h>
14#include <asm/spitfire.h>
15#include <asm-generic/uaccess-unaligned.h>
16#endif
17
18#ifndef __ASSEMBLY__
19
20#include <asm/processor.h>
21
22/*
23 * Sparc64 is segmented, though more like the M68K than the I386.
24 * We use the secondary ASI to address user memory, which references a
25 * completely different VM map, thus there is zero chance of the user
26 * doing something queer and tricking us into poking kernel memory.
27 *
28 * What is left here is basically what is needed for the other parts of
29 * the kernel that expect to be able to manipulate, erum, "segments".
30 * Or perhaps more properly, permissions.
31 *
32 * "For historical reasons, these macros are grossly misnamed." -Linus
33 */
34
35#define KERNEL_DS   ((mm_segment_t) { ASI_P })
36#define USER_DS     ((mm_segment_t) { ASI_AIUS })	/* har har har */
37
38#define VERIFY_READ	0
39#define VERIFY_WRITE	1
40
41#define get_fs() ((mm_segment_t){(current_thread_info()->current_ds)})
42#define get_ds() (KERNEL_DS)
43
44#define segment_eq(a, b)  ((a).seg == (b).seg)
45
46#define set_fs(val)								\
47do {										\
48	current_thread_info()->current_ds = (val).seg;				\
49	__asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg));	\
50} while(0)
51
52static inline int __access_ok(const void __user * addr, unsigned long size)
53{
54	return 1;
55}
56
57static inline int access_ok(int type, const void __user * addr, unsigned long size)
58{
59	return 1;
60}
61
62/*
63 * The exception table consists of pairs of addresses: the first is the
64 * address of an instruction that is allowed to fault, and the second is
65 * the address at which the program should continue.  No registers are
66 * modified, so it is entirely up to the continuation code to figure out
67 * what to do.
68 *
69 * All the routines below use bits of fixup code that are out of line
70 * with the main instruction path.  This means when everything is well,
71 * we don't even have to jump over them.  Further, they do not intrude
72 * on our cache or tlb entries.
73 */
74
75struct exception_table_entry {
76        unsigned int insn, fixup;
77};
78
79void __ret_efault(void);
80void __retl_efault(void);
81
82/* Uh, these should become the main single-value transfer routines..
83 * They automatically use the right size if we just have the right
84 * pointer type..
85 *
86 * This gets kind of ugly. We want to return _two_ values in "get_user()"
87 * and yet we don't want to do any pointers, because that is too much
88 * of a performance impact. Thus we have a few rather ugly macros here,
89 * and hide all the ugliness from the user.
90 */
91#define put_user(x, ptr) ({ \
92	unsigned long __pu_addr = (unsigned long)(ptr); \
93	__chk_user_ptr(ptr); \
94	__put_user_nocheck((__typeof__(*(ptr)))(x), __pu_addr, sizeof(*(ptr)));\
95})
96
97#define get_user(x, ptr) ({ \
98	unsigned long __gu_addr = (unsigned long)(ptr); \
99	__chk_user_ptr(ptr); \
100	__get_user_nocheck((x), __gu_addr, sizeof(*(ptr)), __typeof__(*(ptr)));\
101})
102
103#define __put_user(x, ptr) put_user(x, ptr)
104#define __get_user(x, ptr) get_user(x, ptr)
105
106struct __large_struct { unsigned long buf[100]; };
107#define __m(x) ((struct __large_struct *)(x))
108
109#define __put_user_nocheck(data, addr, size) ({			\
110	register int __pu_ret;					\
111	switch (size) {						\
112	case 1: __put_user_asm(data, b, addr, __pu_ret); break;	\
113	case 2: __put_user_asm(data, h, addr, __pu_ret); break;	\
114	case 4: __put_user_asm(data, w, addr, __pu_ret); break;	\
115	case 8: __put_user_asm(data, x, addr, __pu_ret); break;	\
116	default: __pu_ret = __put_user_bad(); break;		\
117	}							\
118	__pu_ret;						\
119})
120
121#define __put_user_asm(x, size, addr, ret)				\
122__asm__ __volatile__(							\
123		"/* Put user asm, inline. */\n"				\
124	"1:\t"	"st"#size "a %1, [%2] %%asi\n\t"			\
125		"clr	%0\n"						\
126	"2:\n\n\t"							\
127		".section .fixup,#alloc,#execinstr\n\t"			\
128		".align	4\n"						\
129	"3:\n\t"							\
130		"sethi	%%hi(2b), %0\n\t"				\
131		"jmpl	%0 + %%lo(2b), %%g0\n\t"			\
132		" mov	%3, %0\n\n\t"					\
133		".previous\n\t"						\
134		".section __ex_table,\"a\"\n\t"				\
135		".align	4\n\t"						\
136		".word	1b, 3b\n\t"					\
137		".previous\n\n\t"					\
138	       : "=r" (ret) : "r" (x), "r" (__m(addr)),			\
139		 "i" (-EFAULT))
140
141int __put_user_bad(void);
142
143#define __get_user_nocheck(data, addr, size, type) ({			     \
144	register int __gu_ret;						     \
145	register unsigned long __gu_val;				     \
146	switch (size) {							     \
147		case 1: __get_user_asm(__gu_val, ub, addr, __gu_ret); break; \
148		case 2: __get_user_asm(__gu_val, uh, addr, __gu_ret); break; \
149		case 4: __get_user_asm(__gu_val, uw, addr, __gu_ret); break; \
150		case 8: __get_user_asm(__gu_val, x, addr, __gu_ret); break;  \
151		default:						     \
152			__gu_val = 0;					     \
153			__gu_ret = __get_user_bad();			     \
154			break;						     \
155	} 								     \
156	data = (__force type) __gu_val;					     \
157	 __gu_ret;							     \
158})
159
160#define __get_user_nocheck_ret(data, addr, size, type, retval) ({	\
161	register unsigned long __gu_val __asm__ ("l1");			\
162	switch (size) {							\
163	case 1: __get_user_asm_ret(__gu_val, ub, addr, retval); break;	\
164	case 2: __get_user_asm_ret(__gu_val, uh, addr, retval); break;	\
165	case 4: __get_user_asm_ret(__gu_val, uw, addr, retval); break;	\
166	case 8: __get_user_asm_ret(__gu_val, x, addr, retval); break;	\
167	default:							\
168		if (__get_user_bad())					\
169			return retval;					\
170	}								\
171	data = (__force type) __gu_val;					\
172})
173
174#define __get_user_asm(x, size, addr, ret)				\
175__asm__ __volatile__(							\
176		"/* Get user asm, inline. */\n"				\
177	"1:\t"	"ld"#size "a [%2] %%asi, %1\n\t"			\
178		"clr	%0\n"						\
179	"2:\n\n\t"							\
180		".section .fixup,#alloc,#execinstr\n\t"			\
181		".align	4\n"						\
182	"3:\n\t"							\
183		"sethi	%%hi(2b), %0\n\t"				\
184		"clr	%1\n\t"						\
185		"jmpl	%0 + %%lo(2b), %%g0\n\t"			\
186		" mov	%3, %0\n\n\t"					\
187		".previous\n\t"						\
188		".section __ex_table,\"a\"\n\t"				\
189		".align	4\n\t"						\
190		".word	1b, 3b\n\n\t"					\
191		".previous\n\t"						\
192	       : "=r" (ret), "=r" (x) : "r" (__m(addr)),		\
193		 "i" (-EFAULT))
194
195#define __get_user_asm_ret(x, size, addr, retval)			\
196if (__builtin_constant_p(retval) && retval == -EFAULT)			\
197	__asm__ __volatile__(						\
198		"/* Get user asm ret, inline. */\n"			\
199	"1:\t"	"ld"#size "a [%1] %%asi, %0\n\n\t"			\
200		".section __ex_table,\"a\"\n\t"				\
201		".align	4\n\t"						\
202		".word	1b,__ret_efault\n\n\t"				\
203		".previous\n\t"						\
204	       : "=r" (x) : "r" (__m(addr)));				\
205else									\
206	__asm__ __volatile__(						\
207		"/* Get user asm ret, inline. */\n"			\
208	"1:\t"	"ld"#size "a [%1] %%asi, %0\n\n\t"			\
209		".section .fixup,#alloc,#execinstr\n\t"			\
210		".align	4\n"						\
211	"3:\n\t"							\
212		"ret\n\t"						\
213		" restore %%g0, %2, %%o0\n\n\t"				\
214		".previous\n\t"						\
215		".section __ex_table,\"a\"\n\t"				\
216		".align	4\n\t"						\
217		".word	1b, 3b\n\n\t"					\
218		".previous\n\t"						\
219	       : "=r" (x) : "r" (__m(addr)), "i" (retval))
220
221int __get_user_bad(void);
222
223unsigned long __must_check ___copy_from_user(void *to,
224					     const void __user *from,
225					     unsigned long size);
226unsigned long copy_from_user_fixup(void *to, const void __user *from,
227				   unsigned long size);
228static inline unsigned long __must_check
229copy_from_user(void *to, const void __user *from, unsigned long size)
230{
231	unsigned long ret = ___copy_from_user(to, from, size);
232
233	if (unlikely(ret))
234		ret = copy_from_user_fixup(to, from, size);
235
236	return ret;
237}
238#define __copy_from_user copy_from_user
239
240unsigned long __must_check ___copy_to_user(void __user *to,
241					   const void *from,
242					   unsigned long size);
243unsigned long copy_to_user_fixup(void __user *to, const void *from,
244				 unsigned long size);
245static inline unsigned long __must_check
246copy_to_user(void __user *to, const void *from, unsigned long size)
247{
248	unsigned long ret = ___copy_to_user(to, from, size);
249
250	if (unlikely(ret))
251		ret = copy_to_user_fixup(to, from, size);
252	return ret;
253}
254#define __copy_to_user copy_to_user
255
256unsigned long __must_check ___copy_in_user(void __user *to,
257					   const void __user *from,
258					   unsigned long size);
259unsigned long copy_in_user_fixup(void __user *to, void __user *from,
260				 unsigned long size);
261static inline unsigned long __must_check
262copy_in_user(void __user *to, void __user *from, unsigned long size)
263{
264	unsigned long ret = ___copy_in_user(to, from, size);
265
266	if (unlikely(ret))
267		ret = copy_in_user_fixup(to, from, size);
268	return ret;
269}
270#define __copy_in_user copy_in_user
271
272unsigned long __must_check __clear_user(void __user *, unsigned long);
273
274#define clear_user __clear_user
275
276__must_check long strlen_user(const char __user *str);
277__must_check long strnlen_user(const char __user *str, long n);
278
279#define __copy_to_user_inatomic __copy_to_user
280#define __copy_from_user_inatomic __copy_from_user
281
282struct pt_regs;
283unsigned long compute_effective_address(struct pt_regs *,
284					unsigned int insn,
285					unsigned int rd);
286
287#endif  /* __ASSEMBLY__ */
288
289#endif /* _ASM_UACCESS_H */
290