[deliverable/linux.git] / arch / parisc / include / asm / uaccess.h

#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_KERNEL(ptr)		BUILD_BUG()
#define LDD_USER(ptr)		BUILD_BUG()
#define STD_KERNEL(x, ptr)	__put_kernel_asm64(x, ptr)
#define STD_USER(x, ptr)	__put_user_asm64(x, ptr)
#else
#define LDD_KERNEL(ptr)		__get_kernel_asm("ldd", ptr)
#define LDD_USER(ptr)		__get_user_asm("ldd", ptr)
#define STD_KERNEL(x, ptr)	__put_kernel_asm("std", x, 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;
};

#define __get_user(x, ptr)                               \
({                                                       \
	register long __gu_err __asm__ ("r8") = 0;       \
	register long __gu_val __asm__ ("r9") = 0;       \
							 \
	if (segment_eq(get_fs(), KERNEL_DS)) {           \
	    switch (sizeof(*(ptr))) {                    \
	    case 1: __get_kernel_asm("ldb", ptr); break; \
	    case 2: __get_kernel_asm("ldh", ptr); break; \
	    case 4: __get_kernel_asm("ldw", ptr); break; \
	    case 8: LDD_KERNEL(ptr); break;		 \
	    default: BUILD_BUG(); break;		 \
	    }                                            \
	}                                                \
	else {                                           \
	    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_kernel_asm(ldx, ptr)                      \
	__asm__("\n1:\t" ldx "\t0(%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");

#define __get_user_asm(ldx, ptr)                        \
	__asm__("\n1:\t" ldx "\t0(%%sr3,%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");

#define __put_user(x, ptr)                                      \
({								\
	register long __pu_err __asm__ ("r8") = 0;      	\
        __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x);	\
								\
	if (segment_eq(get_fs(), KERNEL_DS)) {                  \
	    switch (sizeof(*(ptr))) {                           \
	    case 1: __put_kernel_asm("stb", __x, ptr); break;   \
	    case 2: __put_kernel_asm("sth", __x, ptr); break;   \
	    case 4: __put_kernel_asm("stw", __x, ptr); break;   \
	    case 8: STD_KERNEL(__x, ptr); break;		\
	    default: BUILD_BUG(); break;			\
	    }                                                   \
	}                                                       \
	else {                                                  \
	    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_kernel_asm(stx, x, ptr)                       \
	__asm__ __volatile__ (                              \
		"\n1:\t" stx "\t%2,0(%1)\n\t"		    \
		ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
		: "=r"(__pu_err)                            \
		: "r"(ptr), "r"(x), "0"(__pu_err)	    \
	    	: "r1")

#define __put_user_asm(stx, x, ptr)                         \
	__asm__ __volatile__ (                              \
		"\n1:\t" stx "\t%2,0(%%sr3,%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_kernel_asm64(__val, ptr) do {		    \
	__asm__ __volatile__ (				    \
		"\n1:\tstw %2,0(%1)"			    \
		"\n2:\tstw %R2,4(%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)

#define __put_user_asm64(__val, ptr) do {	    	    \
	__asm__ __volatile__ (				    \
		"\n1:\tstw %2,0(%%sr3,%1)"		    \
		"\n2:\tstw %R2,4(%%sr3,%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 copy_from_user_overflow(void)
#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
        __compiletime_error("copy_from_user() buffer size is not provably correct")
#else
        __compiletime_warning("copy_from_user() buffer size is not provably correct")
#endif
;

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 || !__builtin_constant_p(n) || sz >= n))
                ret = __copy_from_user(to, from, n);
        else
                copy_from_user_overflow();

        return ret;
}

struct pt_regs;
int fixup_exception(struct pt_regs *regs);

#endif /* __PARISC_UACCESS_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef __PARISC_UACCESS_H
	2	#define __PARISC_UACCESS_H
	3
	4	/*
	5	* User space memory access functions
	6	*/
1da177e4	7	#include <asm/page.h>
1da177e4	8	#include <asm/cache.h>
888c31fc	9	#include <asm/errno.h>
5b17e1cd	10	#include <asm-generic/uaccess-unaligned.h>
1da177e4	11
8dd95c68 HD	12	#include <linux/bug.h>
8dd95c68 HD	13
1da177e4 LT	14	#define VERIFY_READ 0
	15	#define VERIFY_WRITE 1
	16
	17	#define KERNEL_DS ((mm_segment_t){0})
	18	#define USER_DS ((mm_segment_t){1})
	19
b9762e7b	20	#define segment_eq(a, b) ((a).seg == (b).seg)
1da177e4 LT	21
	22	#define get_ds() (KERNEL_DS)
	23	#define get_fs() (current_thread_info()->addr_limit)
	24	#define set_fs(x) (current_thread_info()->addr_limit = (x))
	25
	26	/*
	27	* Note that since kernel addresses are in a separate address space on
e49332bd	28	* parisc, we don't need to do anything for access_ok().
1da177e4 LT	29	* We just let the page fault handler do the right thing. This also means
	30	* that put_user is the same as __put_user, etc.
	31	*/
	32
a0ffa8f0 HD	33	static inline long access_ok(int type, const void __user * addr,
a0ffa8f0 HD	34	unsigned long size)
1da177e4	35	{
a0ffa8f0	36	return 1;
1da177e4 LT	37	}
1da177e4 LT	38
1da177e4 LT	39	#define put_user __put_user
	40	#define get_user __get_user
	41
ca72a223	42	#if !defined(CONFIG_64BIT)
8dd95c68 HD	43	#define LDD_KERNEL(ptr) BUILD_BUG()
8dd95c68 HD	44	#define LDD_USER(ptr) BUILD_BUG()
b9762e7b MT	45	#define STD_KERNEL(x, ptr) __put_kernel_asm64(x, ptr)
b9762e7b MT	46	#define STD_USER(x, ptr) __put_user_asm64(x, ptr)
1da177e4	47	#else
b9762e7b MT	48	#define LDD_KERNEL(ptr) __get_kernel_asm("ldd", ptr)
	49	#define LDD_USER(ptr) __get_user_asm("ldd", ptr)
	50	#define STD_KERNEL(x, ptr) __put_kernel_asm("std", x, ptr)
	51	#define STD_USER(x, ptr) __put_user_asm("std", x, ptr)
1da177e4 LT	52	#endif
	53
	54	/*
cb910c17 HD	55	* The exception table contains two values: the first is the relative offset to
	56	* the address of the instruction that is allowed to fault, and the second is
	57	* the relative offset to the address of the fixup routine. Since relative
	58	* addresses are used, 32bit values are sufficient even on 64bit kernel.
1da177e4 LT	59	*/
1da177e4 LT	60
0de79858	61	#define ARCH_HAS_RELATIVE_EXTABLE
1da177e4	62	struct exception_table_entry {
0de79858 HD	63	int insn; /* relative address of insn that is allowed to fault. */
0de79858 HD	64	int fixup; /* relative address of fixup routine */
1da177e4 LT	65	};
1da177e4 LT	66
0b3d643f HD	67	#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
0b3d643f HD	68	".section __ex_table,\"aw\"\n" \
0de79858	69	".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \
0b3d643f HD	70	".previous\n"
0b3d643f HD	71
1da177e4 LT	72	/*
	73	* The page fault handler stores, in a per-cpu area, the following information
	74	* if a fixup routine is available.
	75	*/
	76	struct exception_data {
	77	unsigned long fault_ip;
2ef4dfd9	78	unsigned long fault_gp;
1da177e4 LT	79	unsigned long fault_space;
	80	unsigned long fault_addr;
	81	};
	82
b9762e7b MT	83	#define __get_user(x, ptr) \
	84	({ \
	85	register long __gu_err __asm__ ("r8") = 0; \
	86	register long __gu_val __asm__ ("r9") = 0; \
	87	\
	88	if (segment_eq(get_fs(), KERNEL_DS)) { \
	89	switch (sizeof(*(ptr))) { \
	90	case 1: __get_kernel_asm("ldb", ptr); break; \
	91	case 2: __get_kernel_asm("ldh", ptr); break; \
	92	case 4: __get_kernel_asm("ldw", ptr); break; \
	93	case 8: LDD_KERNEL(ptr); break; \
	94	default: BUILD_BUG(); break; \
	95	} \
	96	} \
	97	else { \
	98	switch (sizeof(*(ptr))) { \
	99	case 1: __get_user_asm("ldb", ptr); break; \
	100	case 2: __get_user_asm("ldh", ptr); break; \
	101	case 4: __get_user_asm("ldw", ptr); break; \
	102	case 8: LDD_USER(ptr); break; \
	103	default: BUILD_BUG(); break; \
	104	} \
	105	} \
	106	\
	107	(x) = (__force __typeof__(*(ptr))) __gu_val; \
	108	__gu_err; \
1da177e4 LT	109	})
1da177e4 LT	110
b9762e7b	111	#define __get_kernel_asm(ldx, ptr) \
0b3d643f HD	112	__asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \
0b3d643f HD	113	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
1da177e4 LT	114	: "=r"(__gu_val), "=r"(__gu_err) \
	115	: "r"(ptr), "1"(__gu_err) \
	116	: "r1");
	117
b9762e7b	118	#define __get_user_asm(ldx, ptr) \
0b3d643f	119	__asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \
b9762e7b	120	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
1da177e4 LT	121	: "=r"(__gu_val), "=r"(__gu_err) \
	122	: "r"(ptr), "1"(__gu_err) \
	123	: "r1");
1da177e4	124
b9762e7b	125	#define __put_user(x, ptr) \
1da177e4 LT	126	({ \
	127	register long __pu_err __asm__ ("r8") = 0; \
	128	__typeof__((ptr)) __x = (__typeof__((ptr)))(x); \
	129	\
b9762e7b	130	if (segment_eq(get_fs(), KERNEL_DS)) { \
1da177e4	131	switch (sizeof(*(ptr))) { \
b9762e7b MT	132	case 1: __put_kernel_asm("stb", __x, ptr); break; \
	133	case 2: __put_kernel_asm("sth", __x, ptr); break; \
	134	case 4: __put_kernel_asm("stw", __x, ptr); break; \
	135	case 8: STD_KERNEL(__x, ptr); break; \
8dd95c68	136	default: BUILD_BUG(); break; \
1da177e4 LT	137	} \
	138	} \
	139	else { \
	140	switch (sizeof(*(ptr))) { \
b9762e7b MT	141	case 1: __put_user_asm("stb", __x, ptr); break; \
	142	case 2: __put_user_asm("sth", __x, ptr); break; \
	143	case 4: __put_user_asm("stw", __x, ptr); break; \
	144	case 8: STD_USER(__x, ptr); break; \
8dd95c68	145	default: BUILD_BUG(); break; \
1da177e4 LT	146	} \
	147	} \
	148	\
	149	__pu_err; \
	150	})
	151
	152	/*
	153	* The "__put_user/kernel_asm()" macros tell gcc they read from memory
	154	* instead of writing. This is because they do not write to any memory
3fd3a74f CD	155	* gcc knows about, so there are no aliasing issues. These macros must
	156	* also be aware that "fixup_put_user_skip_[12]" are executed in the
	157	* context of the fault, and any registers used there must be listed
	158	* as clobbers. In this case only "r1" is used by the current routines.
	159	* r8/r9 are already listed as err/val.
1da177e4 LT	160	*/
1da177e4 LT	161
b9762e7b	162	#define __put_kernel_asm(stx, x, ptr) \
1da177e4	163	__asm__ __volatile__ ( \
0b3d643f	164	"\n1:\t" stx "\t%2,0(%1)\n\t" \
b9762e7b	165	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
1da177e4	166	: "=r"(__pu_err) \
3fd3a74f CD	167	: "r"(ptr), "r"(x), "0"(__pu_err) \
3fd3a74f CD	168	: "r1")
1da177e4	169
b9762e7b	170	#define __put_user_asm(stx, x, ptr) \
1da177e4	171	__asm__ __volatile__ ( \
0b3d643f	172	"\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \
b9762e7b	173	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
1da177e4 LT	174	: "=r"(__pu_err) \
	175	: "r"(ptr), "r"(x), "0"(__pu_err) \
	176	: "r1")
	177
1da177e4	178
ca72a223	179	#if !defined(CONFIG_64BIT)
94a1981d	180
b9762e7b	181	#define __put_kernel_asm64(__val, ptr) do { \
1da177e4	182	__asm__ __volatile__ ( \
0b3d643f	183	"\n1:\tstw %2,0(%1)" \
0f28b628	184	"\n2:\tstw %R2,4(%1)\n\t" \
b9762e7b MT	185	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
b9762e7b MT	186	ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
1da177e4	187	: "=r"(__pu_err) \
0f28b628	188	: "r"(ptr), "r"(__val), "0"(__pu_err) \
1da177e4 LT	189	: "r1"); \
	190	} while (0)
	191
b9762e7b	192	#define __put_user_asm64(__val, ptr) do { \
1da177e4	193	__asm__ __volatile__ ( \
0b3d643f	194	"\n1:\tstw %2,0(%%sr3,%1)" \
0f28b628	195	"\n2:\tstw %R2,4(%%sr3,%1)\n\t" \
b9762e7b MT	196	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
b9762e7b MT	197	ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
1da177e4	198	: "=r"(__pu_err) \
0f28b628	199	: "r"(ptr), "r"(__val), "0"(__pu_err) \
1da177e4 LT	200	: "r1"); \
	201	} while (0)
	202
ca72a223	203	#endif /* !defined(CONFIG_64BIT) */
1da177e4 LT	204
	205
	206	/*
	207	* Complex access routines -- external declarations
	208	*/
	209
	210	extern unsigned long lcopy_to_user(void __user , const void , unsigned long);
	211	extern unsigned long lcopy_from_user(void , const void __user , unsigned long);
	212	extern unsigned long lcopy_in_user(void __user , const void __user , unsigned long);
b1195c0e	213	extern long strncpy_from_user(char , const char __user , long);
b9762e7b MT	214	extern unsigned lclear_user(void __user *, unsigned long);
b9762e7b MT	215	extern long lstrnlen_user(const char __user *, long);
1da177e4 LT	216	/*
	217	* Complex access routines -- macros
	218	*/
a0ffa8f0	219	#define user_addr_max() (~0UL)
1da177e4	220
1da177e4 LT	221	#define strnlen_user lstrnlen_user
	222	#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
	223	#define clear_user lclear_user
	224	#define __clear_user lclear_user
	225
	226	unsigned long copy_to_user(void __user dst, const void src, unsigned long len);
	227	#define __copy_to_user copy_to_user
888c31fc	228	unsigned long __copy_from_user(void dst, const void __user src, unsigned long len);
1da177e4 LT	229	unsigned long copy_in_user(void __user dst, const void __user src, unsigned long len);
	230	#define __copy_in_user copy_in_user
	231	#define __copy_to_user_inatomic __copy_to_user
	232	#define __copy_from_user_inatomic __copy_from_user
	233
888c31fc HD	234	extern void copy_from_user_overflow(void)
	235	#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
	236	__compiletime_error("copy_from_user() buffer size is not provably correct")
	237	#else
	238	__compiletime_warning("copy_from_user() buffer size is not provably correct")
	239	#endif
	240	;
	241
	242	static inline unsigned long __must_check copy_from_user(void *to,
	243	const void __user *from,
	244	unsigned long n)
	245	{
	246	int sz = __compiletime_object_size(to);
	247	int ret = -EFAULT;
	248
	249	if (likely(sz == -1 \|\| !__builtin_constant_p(n) \|\| sz >= n))
	250	ret = __copy_from_user(to, from, n);
	251	else
	252	copy_from_user_overflow();
	253
	254	return ret;
	255	}
	256
e448372c	257	struct pt_regs;
c61c25eb KM	258	int fixup_exception(struct pt_regs *regs);
c61c25eb KM	259
1da177e4	260	#endif /* __PARISC_UACCESS_H */