[mirror_ubuntu-artful-kernel.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 <linux/bug.h>
#include <linux/string.h>

#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.
 */

#define access_ok(type, uaddr, size)	\
	( (uaddr) == (uaddr) )

#define put_user __put_user
#define get_user __get_user

#if !defined(CONFIG_64BIT)
#define LDD_USER(val, ptr)	__get_user_asm64(val, ptr)
#define STD_USER(x, ptr)	__put_user_asm64(x, ptr)
#else
#define LDD_USER(val, ptr)	__get_user_asm(val, "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"

/*
 * ASM_EXCEPTIONTABLE_ENTRY_EFAULT() creates a special exception table entry
 * (with lowest bit set) for which the fault handler in fixup_exception() will
 * load -EFAULT into %r8 for a read or write fault, and zeroes the target
 * register in case of a read fault in get_user().
 */
#define ASM_EXCEPTIONTABLE_ENTRY_EFAULT( fault_addr, except_addr )\
	ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr + 1)

/*
 * 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_internal(val, ptr)			\
({							\
	register long __gu_err __asm__ ("r8") = 0;	\
							\
	switch (sizeof(*(ptr))) {			\
	case 1: __get_user_asm(val, "ldb", ptr); break;	\
	case 2: __get_user_asm(val, "ldh", ptr); break; \
	case 4: __get_user_asm(val, "ldw", ptr); break; \
	case 8: LDD_USER(val, ptr); break;		\
	default: BUILD_BUG();				\
	}						\
							\
	__gu_err;					\
})

#define __get_user(val, ptr)				\
({							\
	load_sr2();					\
	__get_user_internal(val, ptr);			\
})

#define __get_user_asm(val, ldx, ptr)			\
{							\
	register long __gu_val;				\
							\
	__asm__("1: " ldx " 0(%%sr2,%2),%0\n"		\
		"9:\n"					\
		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b)	\
		: "=r"(__gu_val), "=r"(__gu_err)        \
		: "r"(ptr), "1"(__gu_err));		\
							\
	(val) = (__force __typeof__(*(ptr))) __gu_val;	\
}

#if !defined(CONFIG_64BIT)

#define __get_user_asm64(val, ptr)			\
{							\
	union {						\
		unsigned long long	l;		\
		__typeof__(*(ptr))	t;		\
	} __gu_tmp;					\
							\
	__asm__("   copy %%r0,%R0\n"			\
		"1: ldw 0(%%sr2,%2),%0\n"		\
		"2: ldw 4(%%sr2,%2),%R0\n"		\
		"9:\n"					\
		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b)	\
		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b)	\
		: "=&r"(__gu_tmp.l), "=r"(__gu_err)	\
		: "r"(ptr), "1"(__gu_err));		\
							\
	(val) = __gu_tmp.t;				\
}

#endif /* !defined(CONFIG_64BIT) */


#define __put_user_internal(x, ptr)				\
({								\
	register long __pu_err __asm__ ("r8") = 0;      	\
        __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x);	\
								\
	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();					\
	}							\
								\
	__pu_err;						\
})

#define __put_user(x, ptr)					\
({								\
	load_sr2();						\
	__put_user_internal(x, ptr);				\
})


/*
 * 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 fixups are executed in the context of the fault,
 * and any registers used there must be listed as clobbers.
 * r8 is already listed as err.
 */

#define __put_user_asm(stx, x, ptr)                         \
	__asm__ __volatile__ (                              \
		"1: " stx " %2,0(%%sr2,%1)\n"		    \
		"9:\n"					    \
		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b)	    \
		: "=r"(__pu_err)                            \
		: "r"(ptr), "r"(x), "0"(__pu_err))


#if !defined(CONFIG_64BIT)

#define __put_user_asm64(__val, ptr) do {	    	    \
	__asm__ __volatile__ (				    \
		"1: stw %2,0(%%sr2,%1)\n"		    \
		"2: stw %R2,4(%%sr2,%1)\n"		    \
		"9:\n"					    \
		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b)	    \
		ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b)	    \
		: "=r"(__pu_err)                            \
		: "r"(ptr), "r"(__val), "0"(__pu_err));	    \
} while (0)

#endif /* !defined(CONFIG_64BIT) */


/*
 * Complex access routines -- external declarations
 */

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 clear_user lclear_user
#define __clear_user lclear_user

unsigned long __must_check raw_copy_to_user(void __user *dst, const void *src,
					    unsigned long len);
unsigned long __must_check raw_copy_from_user(void *dst, const void __user *src,
					    unsigned long len);
unsigned long __must_check raw_copy_in_user(void __user *dst, const void __user *src,
					    unsigned long len);
#define INLINE_COPY_TO_USER
#define INLINE_COPY_FROM_USER

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>
1da177e4	9
8dd95c68	10	#include <linux/bug.h>
aace880f	11	#include <linux/string.h>
1da177e4 LT	12
	13	#define KERNEL_DS ((mm_segment_t){0})
	14	#define USER_DS ((mm_segment_t){1})
	15
b9762e7b	16	#define segment_eq(a, b) ((a).seg == (b).seg)
1da177e4 LT	17
	18	#define get_ds() (KERNEL_DS)
	19	#define get_fs() (current_thread_info()->addr_limit)
	20	#define set_fs(x) (current_thread_info()->addr_limit = (x))
	21
	22	/*
	23	* Note that since kernel addresses are in a separate address space on
e49332bd	24	* parisc, we don't need to do anything for access_ok().
1da177e4 LT	25	* We just let the page fault handler do the right thing. This also means
	26	* that put_user is the same as __put_user, etc.
	27	*/
	28
186ecf14 HD	29	#define access_ok(type, uaddr, size) \
186ecf14 HD	30	( (uaddr) == (uaddr) )
1da177e4	31
1da177e4 LT	32	#define put_user __put_user
	33	#define get_user __get_user
	34
ca72a223	35	#if !defined(CONFIG_64BIT)
3f795cef	36	#define LDD_USER(val, ptr) __get_user_asm64(val, ptr)
b9762e7b	37	#define STD_USER(x, ptr) __put_user_asm64(x, ptr)
1da177e4	38	#else
3f795cef	39	#define LDD_USER(val, ptr) __get_user_asm(val, "ldd", ptr)
b9762e7b	40	#define STD_USER(x, ptr) __put_user_asm("std", x, ptr)
1da177e4 LT	41	#endif
	42
	43	/*
cb910c17 HD	44	* The exception table contains two values: the first is the relative offset to
	45	* the address of the instruction that is allowed to fault, and the second is
	46	* the relative offset to the address of the fixup routine. Since relative
	47	* addresses are used, 32bit values are sufficient even on 64bit kernel.
1da177e4 LT	48	*/
1da177e4 LT	49
0de79858	50	#define ARCH_HAS_RELATIVE_EXTABLE
1da177e4	51	struct exception_table_entry {
0de79858 HD	52	int insn; /* relative address of insn that is allowed to fault. */
0de79858 HD	53	int fixup; /* relative address of fixup routine */
1da177e4 LT	54	};
1da177e4 LT	55
0b3d643f HD	56	#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
0b3d643f HD	57	".section __ex_table,\"aw\"\n" \
0de79858	58	".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \
0b3d643f HD	59	".previous\n"
0b3d643f HD	60
d19f5e41 HD	61	/*
	62	* ASM_EXCEPTIONTABLE_ENTRY_EFAULT() creates a special exception table entry
	63	* (with lowest bit set) for which the fault handler in fixup_exception() will
	64	* load -EFAULT into %r8 for a read or write fault, and zeroes the target
	65	* register in case of a read fault in get_user().
	66	*/
	67	#define ASM_EXCEPTIONTABLE_ENTRY_EFAULT( fault_addr, except_addr )\
	68	ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr + 1)
	69
06bff6b9 HD	70	/*
	71	* load_sr2() preloads the space register %%sr2 - based on the value of
	72	* get_fs() - with either a value of 0 to access kernel space (KERNEL_DS which
	73	* is 0), or with the current value of %%sr3 to access user space (USER_DS)
	74	* memory. The following __get_user_asm() and __put_user_asm() functions have
	75	* %%sr2 hard-coded to access the requested memory.
	76	*/
	77	#define load_sr2() \
	78	__asm__(" or,= %0,%%r0,%%r0\n\t" \
	79	" mfsp %%sr3,%0\n\t" \
	80	" mtsp %0,%%sr2\n\t" \
	81	: : "r"(get_fs()) : )
	82
3f795cef HD	83	#define __get_user_internal(val, ptr) \
	84	({ \
	85	register long __gu_err __asm__ ("r8") = 0; \
	86	\
	87	switch (sizeof(*(ptr))) { \
	88	case 1: __get_user_asm(val, "ldb", ptr); break; \
	89	case 2: __get_user_asm(val, "ldh", ptr); break; \
	90	case 4: __get_user_asm(val, "ldw", ptr); break; \
	91	case 8: LDD_USER(val, ptr); break; \
	92	default: BUILD_BUG(); \
	93	} \
	94	\
	95	__gu_err; \
1da177e4 LT	96	})
1da177e4 LT	97
3f795cef HD	98	#define __get_user(val, ptr) \
	99	({ \
	100	load_sr2(); \
	101	__get_user_internal(val, ptr); \
	102	})
	103
	104	#define __get_user_asm(val, ldx, ptr) \
	105	{ \
	106	register long __gu_val; \
	107	\
d19f5e41 HD	108	__asm__("1: " ldx " 0(%%sr2,%2),%0\n" \
	109	"9:\n" \
	110	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
1da177e4	111	: "=r"(__gu_val), "=r"(__gu_err) \
3f795cef HD	112	: "r"(ptr), "1"(__gu_err)); \
	113	\
	114	(val) = (__force __typeof__(*(ptr))) __gu_val; \
	115	}
1da177e4	116
d2ad824f HD	117	#if !defined(CONFIG_64BIT)
d2ad824f HD	118
3f795cef HD	119	#define __get_user_asm64(val, ptr) \
	120	{ \
	121	union { \
	122	unsigned long long l; \
	123	__typeof__(*(ptr)) t; \
	124	} __gu_tmp; \
	125	\
d19f5e41 HD	126	__asm__(" copy %%r0,%R0\n" \
	127	"1: ldw 0(%%sr2,%2),%0\n" \
	128	"2: ldw 4(%%sr2,%2),%R0\n" \
	129	"9:\n" \
	130	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
	131	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \
3f795cef HD	132	: "=&r"(__gu_tmp.l), "=r"(__gu_err) \
	133	: "r"(ptr), "1"(__gu_err)); \
	134	\
	135	(val) = __gu_tmp.t; \
	136	}
d2ad824f HD	137
	138	#endif /* !defined(CONFIG_64BIT) */
	139
	140
3f795cef	141	#define __put_user_internal(x, ptr) \
1da177e4 LT	142	({ \
	143	register long __pu_err __asm__ ("r8") = 0; \
	144	__typeof__((ptr)) __x = (__typeof__((ptr)))(x); \
	145	\
06bff6b9	146	switch (sizeof(*(ptr))) { \
3f795cef HD	147	case 1: __put_user_asm("stb", __x, ptr); break; \
	148	case 2: __put_user_asm("sth", __x, ptr); break; \
	149	case 4: __put_user_asm("stw", __x, ptr); break; \
	150	case 8: STD_USER(__x, ptr); break; \
	151	default: BUILD_BUG(); \
	152	} \
1da177e4 LT	153	\
	154	__pu_err; \
	155	})
	156
3f795cef HD	157	#define __put_user(x, ptr) \
	158	({ \
	159	load_sr2(); \
	160	__put_user_internal(x, ptr); \
	161	})
	162
	163
1da177e4 LT	164	/*
	165	* The "__put_user/kernel_asm()" macros tell gcc they read from memory
	166	* instead of writing. This is because they do not write to any memory
3fd3a74f	167	* gcc knows about, so there are no aliasing issues. These macros must
d19f5e41 HD	168	* also be aware that fixups are executed in the context of the fault,
	169	* and any registers used there must be listed as clobbers.
	170	* r8 is already listed as err.
1da177e4 LT	171	*/
1da177e4 LT	172
b9762e7b	173	#define __put_user_asm(stx, x, ptr) \
1da177e4	174	__asm__ __volatile__ ( \
d19f5e41 HD	175	"1: " stx " %2,0(%%sr2,%1)\n" \
	176	"9:\n" \
	177	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
1da177e4	178	: "=r"(__pu_err) \
d19f5e41	179	: "r"(ptr), "r"(x), "0"(__pu_err))
1da177e4	180
1da177e4	181
ca72a223	182	#if !defined(CONFIG_64BIT)
94a1981d	183
b9762e7b	184	#define __put_user_asm64(__val, ptr) do { \
1da177e4	185	__asm__ __volatile__ ( \
d19f5e41 HD	186	"1: stw %2,0(%%sr2,%1)\n" \
	187	"2: stw %R2,4(%%sr2,%1)\n" \
	188	"9:\n" \
	189	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
	190	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \
1da177e4	191	: "=r"(__pu_err) \
d19f5e41	192	: "r"(ptr), "r"(__val), "0"(__pu_err)); \
1da177e4 LT	193	} while (0)
1da177e4 LT	194
ca72a223	195	#endif /* !defined(CONFIG_64BIT) */
1da177e4 LT	196
	197
	198	/*
	199	* Complex access routines -- external declarations
	200	*/
	201
b1195c0e	202	extern long strncpy_from_user(char , const char __user , long);
b9762e7b MT	203	extern unsigned lclear_user(void __user *, unsigned long);
b9762e7b MT	204	extern long lstrnlen_user(const char __user *, long);
1da177e4 LT	205	/*
	206	* Complex access routines -- macros
	207	*/
a0ffa8f0	208	#define user_addr_max() (~0UL)
1da177e4	209
1da177e4	210	#define strnlen_user lstrnlen_user
1da177e4 LT	211	#define clear_user lclear_user
	212	#define __clear_user lclear_user
	213
f64fd180 AV	214	unsigned long __must_check raw_copy_to_user(void __user dst, const void src,
	215	unsigned long len);
	216	unsigned long __must_check raw_copy_from_user(void dst, const void __user src,
	217	unsigned long len);
	218	unsigned long __must_check raw_copy_in_user(void __user dst, const void __user src,
	219	unsigned long len);
	220	#define INLINE_COPY_TO_USER
	221	#define INLINE_COPY_FROM_USER
888c31fc	222
e448372c	223	struct pt_regs;
c61c25eb KM	224	int fixup_exception(struct pt_regs *regs);
c61c25eb KM	225
1da177e4	226	#endif /* __PARISC_UACCESS_H */