[thirdparty/kernel/stable.git] / arch / nds32 / include / asm / uaccess.h

/* SPDX-License-Identifier: GPL-2.0 */
// Copyright (C) 2005-2017 Andes Technology Corporation

#ifndef _ASMANDES_UACCESS_H
#define _ASMANDES_UACCESS_H

/*
 * User space memory access functions
 */
#include <linux/sched.h>
#include <asm/errno.h>
#include <asm/memory.h>
#include <asm/types.h>
#include <asm-generic/access_ok.h>

#define __asmeq(x, y)  ".ifnc " x "," y " ; .err ; .endif\n\t"

/*
 * The exception table consists of pairs of addresses: the first is the
 * address of an instruction that is allowed to fault, and the second is
 * the address at which the program should continue.  No registers are
 * modified, so it is entirely up to the continuation code to figure out
 * what to do.
 *
 * All the routines below use bits of fixup code that are out of line
 * with the main instruction path.  This means when everything is well,
 * we don't even have to jump over them.  Further, they do not intrude
 * on our cache or tlb entries.
 */

struct exception_table_entry {
	unsigned long insn, fixup;
};

extern int fixup_exception(struct pt_regs *regs);

/*
 * Single-value transfer routines.  They automatically use the right
 * size if we just have the right pointer type.  Note that the functions
 * which read from user space (*get_*) need to take care not to leak
 * kernel data even if the calling code is buggy and fails to check
 * the return value.  This means zeroing out the destination variable
 * or buffer on error.  Normally this is done out of line by the
 * fixup code, but there are a few places where it intrudes on the
 * main code path.  When we only write to user space, there is no
 * problem.
 *
 * The "__xxx" versions of the user access functions do not verify the
 * address space - it must have been done previously with a separate
 * "access_ok()" call.
 *
 * The "xxx_error" versions set the third argument to EFAULT if an
 * error occurs, and leave it unchanged on success.  Note that these
 * versions are void (ie, don't return a value as such).
 */

#define get_user(x, ptr)						\
({									\
	long __gu_err = 0;						\
	__get_user_check((x), (ptr), __gu_err);				\
	__gu_err;							\
})

#define __get_user_error(x, ptr, err)					\
({									\
	__get_user_check((x), (ptr), (err));				\
	(void)0;							\
})

#define __get_user(x, ptr)						\
({									\
	long __gu_err = 0;						\
	const __typeof__(*(ptr)) __user *__p = (ptr);			\
	__get_user_err((x), __p, (__gu_err));				\
	__gu_err;							\
})

#define __get_user_check(x, ptr, err)					\
({									\
	const __typeof__(*(ptr)) __user *__p = (ptr);			\
	might_fault();							\
	if (access_ok(__p, sizeof(*__p))) {		\
		__get_user_err((x), __p, (err));			\
	} else {							\
		(x) = 0; (err) = -EFAULT;				\
	}								\
})

#define __get_user_err(x, ptr, err)					\
do {									\
	unsigned long __gu_val;						\
	__chk_user_ptr(ptr);						\
	switch (sizeof(*(ptr))) {					\
	case 1:								\
		__get_user_asm("lbi", __gu_val, (ptr), (err));		\
		break;							\
	case 2:								\
		__get_user_asm("lhi", __gu_val, (ptr), (err));		\
		break;							\
	case 4:								\
		__get_user_asm("lwi", __gu_val, (ptr), (err));		\
		break;							\
	case 8:								\
		__get_user_asm_dword(__gu_val, (ptr), (err));		\
		break;							\
	default:							\
		BUILD_BUG(); 						\
		break;							\
	}								\
	(x) = (__force __typeof__(*(ptr)))__gu_val;			\
} while (0)

#define __get_user_asm(inst, x, addr, err)				\
	__asm__ __volatile__ (						\
		"1:	"inst"	%1,[%2]\n"				\
		"2:\n"							\
		"	.section .fixup,\"ax\"\n"			\
		"	.align	2\n"					\
		"3:	move %0, %3\n"					\
		"	move %1, #0\n"					\
		"	b	2b\n"					\
		"	.previous\n"					\
		"	.section __ex_table,\"a\"\n"			\
		"	.align	3\n"					\
		"	.long	1b, 3b\n"				\
		"	.previous"					\
		: "+r" (err), "=&r" (x)					\
		: "r" (addr), "i" (-EFAULT)				\
		: "cc")

#ifdef __NDS32_EB__
#define __gu_reg_oper0 "%H1"
#define __gu_reg_oper1 "%L1"
#else
#define __gu_reg_oper0 "%L1"
#define __gu_reg_oper1 "%H1"
#endif

#define __get_user_asm_dword(x, addr, err) 				\
	__asm__ __volatile__ (						\
		"\n1:\tlwi " __gu_reg_oper0 ",[%2]\n"			\
		"\n2:\tlwi " __gu_reg_oper1 ",[%2+4]\n"			\
		"3:\n"							\
		"	.section .fixup,\"ax\"\n"			\
		"	.align	2\n"					\
		"4:	move	%0, %3\n"				\
		"	b	3b\n"					\
		"	.previous\n"					\
		"	.section __ex_table,\"a\"\n"			\
		"	.align	3\n"					\
		"	.long	1b, 4b\n"				\
		"	.long	2b, 4b\n"				\
		"	.previous"					\
		: "+r"(err), "=&r"(x)					\
		: "r"(addr), "i"(-EFAULT)				\
		: "cc")

#define put_user(x, ptr)						\
({									\
	long __pu_err = 0;						\
	__put_user_check((x), (ptr), __pu_err);				\
	__pu_err;							\
})

#define __put_user(x, ptr)						\
({									\
	long __pu_err = 0;						\
	__typeof__(*(ptr)) __user *__p = (ptr);				\
	__put_user_err((x), __p, __pu_err);				\
	__pu_err;							\
})

#define __put_user_error(x, ptr, err)					\
({									\
	__put_user_err((x), (ptr), (err));				\
	(void)0;							\
})

#define __put_user_check(x, ptr, err)					\
({									\
	__typeof__(*(ptr)) __user *__p = (ptr);				\
	might_fault();							\
	if (access_ok(__p, sizeof(*__p))) {		\
		__put_user_err((x), __p, (err));			\
	} else	{							\
		(err) = -EFAULT;					\
	}								\
})

#define __put_user_err(x, ptr, err)					\
do {									\
	__typeof__(*(ptr)) __pu_val = (x);				\
	__chk_user_ptr(ptr);						\
	switch (sizeof(*(ptr))) {					\
	case 1:								\
		__put_user_asm("sbi", __pu_val, (ptr), (err));		\
		break;							\
	case 2: 							\
		__put_user_asm("shi", __pu_val, (ptr), (err));		\
		break;							\
	case 4: 							\
		__put_user_asm("swi", __pu_val, (ptr), (err));		\
		break;							\
	case 8:								\
		__put_user_asm_dword(__pu_val, (ptr), (err));		\
		break;							\
	default:							\
		BUILD_BUG(); 						\
		break;							\
	}								\
} while (0)

#define __put_user_asm(inst, x, addr, err)				\
	__asm__ __volatile__ (						\
		"1:	"inst"	%1,[%2]\n"				\
		"2:\n"							\
		"	.section .fixup,\"ax\"\n"			\
		"	.align	2\n"					\
		"3:	move	%0, %3\n"				\
		"	b	2b\n"					\
		"	.previous\n"					\
		"	.section __ex_table,\"a\"\n"			\
		"	.align	3\n"					\
		"	.long	1b, 3b\n"				\
		"	.previous"					\
		: "+r" (err)						\
		: "r" (x), "r" (addr), "i" (-EFAULT)			\
		: "cc")

#ifdef __NDS32_EB__
#define __pu_reg_oper0 "%H2"
#define __pu_reg_oper1 "%L2"
#else
#define __pu_reg_oper0 "%L2"
#define __pu_reg_oper1 "%H2"
#endif

#define __put_user_asm_dword(x, addr, err) 				\
	__asm__ __volatile__ (						\
		"\n1:\tswi " __pu_reg_oper0 ",[%1]\n"			\
		"\n2:\tswi " __pu_reg_oper1 ",[%1+4]\n"			\
		"3:\n"							\
		"	.section .fixup,\"ax\"\n"			\
		"	.align	2\n"					\
		"4:	move	%0, %3\n"				\
		"	b	3b\n"					\
		"	.previous\n"					\
		"	.section __ex_table,\"a\"\n"			\
		"	.align	3\n"					\
		"	.long	1b, 4b\n"				\
		"	.long	2b, 4b\n"				\
		"	.previous"					\
		: "+r"(err)						\
		: "r"(addr), "r"(x), "i"(-EFAULT)			\
		: "cc")

extern unsigned long __arch_clear_user(void __user * addr, unsigned long n);
extern long strncpy_from_user(char *dest, const char __user * src, long count);
extern __must_check long strnlen_user(const char __user * str, long n);
extern unsigned long __arch_copy_from_user(void *to, const void __user * from,
                                           unsigned long n);
extern unsigned long __arch_copy_to_user(void __user * to, const void *from,
                                         unsigned long n);

#define raw_copy_from_user __arch_copy_from_user
#define raw_copy_to_user __arch_copy_to_user

#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER
static inline unsigned long clear_user(void __user * to, unsigned long n)
{
	if (access_ok(to, n))
		n = __arch_clear_user(to, n);
	return n;
}

static inline unsigned long __clear_user(void __user * to, unsigned long n)
{
	return __arch_clear_user(to, n);
}

#endif /* _ASMNDS32_UACCESS_H */
Commit	Line	Data
7f9ea6b7	1	/* SPDX-License-Identifier: GPL-2.0 */
ace02e2b GH	2	// Copyright (C) 2005-2017 Andes Technology Corporation
	3
	4	#ifndef _ASMANDES_UACCESS_H
	5	#define _ASMANDES_UACCESS_H
	6
	7	/*
	8	* User space memory access functions
	9	*/
	10	#include <linux/sched.h>
	11	#include <asm/errno.h>
	12	#include <asm/memory.h>
	13	#include <asm/types.h>
967747bb	14	#include <asm-generic/access_ok.h>
ace02e2b	15
ace02e2b GH	16	#define __asmeq(x, y) ".ifnc " x "," y " ; .err ; .endif\n\t"
	17
	18	/*
	19	* The exception table consists of pairs of addresses: the first is the
	20	* address of an instruction that is allowed to fault, and the second is
	21	* the address at which the program should continue. No registers are
	22	* modified, so it is entirely up to the continuation code to figure out
	23	* what to do.
	24	*
	25	* All the routines below use bits of fixup code that are out of line
	26	* with the main instruction path. This means when everything is well,
	27	* we don't even have to jump over them. Further, they do not intrude
	28	* on our cache or tlb entries.
	29	*/
	30
	31	struct exception_table_entry {
	32	unsigned long insn, fixup;
	33	};
	34
	35	extern int fixup_exception(struct pt_regs *regs);
	36
ace02e2b GH	37	/*
	38	* Single-value transfer routines. They automatically use the right
	39	* size if we just have the right pointer type. Note that the functions
	40	* which read from user space (get_) need to take care not to leak
	41	* kernel data even if the calling code is buggy and fails to check
	42	* the return value. This means zeroing out the destination variable
	43	* or buffer on error. Normally this is done out of line by the
	44	* fixup code, but there are a few places where it intrudes on the
	45	* main code path. When we only write to user space, there is no
	46	* problem.
	47	*
	48	* The "__xxx" versions of the user access functions do not verify the
	49	* address space - it must have been done previously with a separate
	50	* "access_ok()" call.
	51	*
	52	* The "xxx_error" versions set the third argument to EFAULT if an
	53	* error occurs, and leave it unchanged on success. Note that these
	54	* versions are void (ie, don't return a value as such).
	55	*/
	56
8926d88c	57	#define get_user(x, ptr) \
ace02e2b GH	58	({ \
ace02e2b GH	59	long __gu_err = 0; \
487913ab	60	__get_user_check((x), (ptr), __gu_err); \
ace02e2b GH	61	__gu_err; \
	62	})
	63
7ef39548	64	#define __get_user_error(x, ptr, err) \
ace02e2b	65	({ \
487913ab	66	__get_user_check((x), (ptr), (err)); \
7ef39548	67	(void)0; \
ace02e2b GH	68	})
ace02e2b GH	69
8926d88c AB	70	#define __get_user(x, ptr) \
	71	({ \
	72	long __gu_err = 0; \
	73	const __typeof__((ptr)) __user __p = (ptr); \
	74	__get_user_err((x), __p, (__gu_err)); \
	75	__gu_err; \
	76	})
	77
487913ab ZL	78	#define __get_user_check(x, ptr, err) \
	79	({ \
	80	const __typeof__((ptr)) __user __p = (ptr); \
	81	might_fault(); \
96d4f267	82	if (access_ok(__p, sizeof(*__p))) { \
487913ab ZL	83	__get_user_err((x), __p, (err)); \
	84	} else { \
	85	(x) = 0; (err) = -EFAULT; \
	86	} \
	87	})
	88
7ef39548	89	#define __get_user_err(x, ptr, err) \
ace02e2b	90	do { \
ace02e2b	91	unsigned long __gu_val; \
487913ab ZL	92	__chk_user_ptr(ptr); \
487913ab ZL	93	switch (sizeof(*(ptr))) { \
ace02e2b	94	case 1: \
487913ab	95	__get_user_asm("lbi", __gu_val, (ptr), (err)); \
ace02e2b GH	96	break; \
ace02e2b GH	97	case 2: \
487913ab	98	__get_user_asm("lhi", __gu_val, (ptr), (err)); \
ace02e2b GH	99	break; \
ace02e2b GH	100	case 4: \
487913ab	101	__get_user_asm("lwi", __gu_val, (ptr), (err)); \
ace02e2b GH	102	break; \
ace02e2b GH	103	case 8: \
487913ab	104	__get_user_asm_dword(__gu_val, (ptr), (err)); \
ace02e2b GH	105	break; \
	106	default: \
	107	BUILD_BUG(); \
	108	break; \
	109	} \
487913ab	110	(x) = (__force __typeof__(*(ptr)))__gu_val; \
ace02e2b GH	111	} while (0)
ace02e2b GH	112
7ef39548 ZL	113	#define __get_user_asm(inst, x, addr, err) \
	114	__asm__ __volatile__ ( \
	115	"1: "inst" %1,[%2]\n" \
	116	"2:\n" \
	117	" .section .fixup,\"ax\"\n" \
	118	" .align 2\n" \
	119	"3: move %0, %3\n" \
	120	" move %1, #0\n" \
	121	" b 2b\n" \
	122	" .previous\n" \
	123	" .section __ex_table,\"a\"\n" \
	124	" .align 3\n" \
	125	" .long 1b, 3b\n" \
	126	" .previous" \
	127	: "+r" (err), "=&r" (x) \
	128	: "r" (addr), "i" (-EFAULT) \
	129	: "cc")
ace02e2b GH	130
	131	#ifdef __NDS32_EB__
	132	#define __gu_reg_oper0 "%H1"
	133	#define __gu_reg_oper1 "%L1"
	134	#else
	135	#define __gu_reg_oper0 "%L1"
	136	#define __gu_reg_oper1 "%H1"
	137	#endif
	138
	139	#define __get_user_asm_dword(x, addr, err) \
7ef39548 ZL	140	__asm__ __volatile__ ( \
	141	"\n1:\tlwi " __gu_reg_oper0 ",[%2]\n" \
	142	"\n2:\tlwi " __gu_reg_oper1 ",[%2+4]\n" \
	143	"3:\n" \
	144	" .section .fixup,\"ax\"\n" \
	145	" .align 2\n" \
	146	"4: move %0, %3\n" \
	147	" b 3b\n" \
	148	" .previous\n" \
	149	" .section __ex_table,\"a\"\n" \
	150	" .align 3\n" \
	151	" .long 1b, 4b\n" \
	152	" .long 2b, 4b\n" \
	153	" .previous" \
	154	: "+r"(err), "=&r"(x) \
	155	: "r"(addr), "i"(-EFAULT) \
	156	: "cc")
	157
8926d88c AB	158	#define put_user(x, ptr) \
	159	({ \
	160	long __pu_err = 0; \
	161	__put_user_check((x), (ptr), __pu_err); \
	162	__pu_err; \
	163	})
7ef39548 ZL	164
7ef39548 ZL	165	#define __put_user(x, ptr) \
ace02e2b GH	166	({ \
ace02e2b GH	167	long __pu_err = 0; \
8926d88c AB	168	__typeof__((ptr)) __user __p = (ptr); \
8926d88c AB	169	__put_user_err((x), __p, __pu_err); \
ace02e2b GH	170	__pu_err; \
	171	})
	172
7ef39548	173	#define __put_user_error(x, ptr, err) \
ace02e2b	174	({ \
487913ab	175	__put_user_err((x), (ptr), (err)); \
7ef39548	176	(void)0; \
ace02e2b GH	177	})
ace02e2b GH	178
487913ab ZL	179	#define __put_user_check(x, ptr, err) \
	180	({ \
	181	__typeof__((ptr)) __user __p = (ptr); \
	182	might_fault(); \
96d4f267	183	if (access_ok(__p, sizeof(*__p))) { \
487913ab ZL	184	__put_user_err((x), __p, (err)); \
	185	} else { \
	186	(err) = -EFAULT; \
	187	} \
	188	})
	189
7ef39548	190	#define __put_user_err(x, ptr, err) \
ace02e2b	191	do { \
487913ab ZL	192	__typeof__(*(ptr)) __pu_val = (x); \
	193	__chk_user_ptr(ptr); \
	194	switch (sizeof(*(ptr))) { \
ace02e2b	195	case 1: \
487913ab	196	__put_user_asm("sbi", __pu_val, (ptr), (err)); \
ace02e2b GH	197	break; \
ace02e2b GH	198	case 2: \
487913ab	199	__put_user_asm("shi", __pu_val, (ptr), (err)); \
ace02e2b GH	200	break; \
ace02e2b GH	201	case 4: \
487913ab	202	__put_user_asm("swi", __pu_val, (ptr), (err)); \
ace02e2b GH	203	break; \
ace02e2b GH	204	case 8: \
487913ab	205	__put_user_asm_dword(__pu_val, (ptr), (err)); \
ace02e2b GH	206	break; \
	207	default: \
	208	BUILD_BUG(); \
	209	break; \
	210	} \
	211	} while (0)
	212
7ef39548 ZL	213	#define __put_user_asm(inst, x, addr, err) \
	214	__asm__ __volatile__ ( \
	215	"1: "inst" %1,[%2]\n" \
	216	"2:\n" \
	217	" .section .fixup,\"ax\"\n" \
	218	" .align 2\n" \
	219	"3: move %0, %3\n" \
	220	" b 2b\n" \
	221	" .previous\n" \
	222	" .section __ex_table,\"a\"\n" \
	223	" .align 3\n" \
	224	" .long 1b, 3b\n" \
	225	" .previous" \
	226	: "+r" (err) \
	227	: "r" (x), "r" (addr), "i" (-EFAULT) \
	228	: "cc")
ace02e2b GH	229
	230	#ifdef __NDS32_EB__
	231	#define __pu_reg_oper0 "%H2"
	232	#define __pu_reg_oper1 "%L2"
	233	#else
	234	#define __pu_reg_oper0 "%L2"
	235	#define __pu_reg_oper1 "%H2"
	236	#endif
	237
	238	#define __put_user_asm_dword(x, addr, err) \
7ef39548 ZL	239	__asm__ __volatile__ ( \
	240	"\n1:\tswi " __pu_reg_oper0 ",[%1]\n" \
	241	"\n2:\tswi " __pu_reg_oper1 ",[%1+4]\n" \
	242	"3:\n" \
	243	" .section .fixup,\"ax\"\n" \
	244	" .align 2\n" \
	245	"4: move %0, %3\n" \
	246	" b 3b\n" \
	247	" .previous\n" \
	248	" .section __ex_table,\"a\"\n" \
	249	" .align 3\n" \
	250	" .long 1b, 4b\n" \
	251	" .long 2b, 4b\n" \
	252	" .previous" \
	253	: "+r"(err) \
	254	: "r"(addr), "r"(x), "i"(-EFAULT) \
	255	: "cc")
	256
ace02e2b GH	257	extern unsigned long __arch_clear_user(void __user * addr, unsigned long n);
ace02e2b GH	258	extern long strncpy_from_user(char dest, const char __user src, long count);
ace02e2b GH	259	extern __must_check long strnlen_user(const char __user * str, long n);
	260	extern unsigned long __arch_copy_from_user(void to, const void __user from,
	261	unsigned long n);
	262	extern unsigned long __arch_copy_to_user(void __user * to, const void *from,
	263	unsigned long n);
	264
	265	#define raw_copy_from_user __arch_copy_from_user
	266	#define raw_copy_to_user __arch_copy_to_user
	267
	268	#define INLINE_COPY_FROM_USER
	269	#define INLINE_COPY_TO_USER
	270	static inline unsigned long clear_user(void __user * to, unsigned long n)
	271	{
96d4f267	272	if (access_ok(to, n))
ace02e2b GH	273	n = __arch_clear_user(to, n);
	274	return n;
	275	}
	276
	277	static inline unsigned long __clear_user(void __user * to, unsigned long n)
	278	{
	279	return __arch_clear_user(to, n);
	280	}
	281
	282	#endif /* _ASMNDS32_UACCESS_H */