arch/nds32/include/asm/uaccess.h - linux - Git at Google

 /* 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>

 #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);

 #define KERNEL_DS 	((mm_segment_t) { ~0UL })
 #define USER_DS		((mm_segment_t) {TASK_SIZE - 1})

 #define get_fs()	(current_thread_info()->addr_limit)
 #define user_addr_max	get_fs

 static inline void set_fs(mm_segment_t fs)
 {
 	current_thread_info()->addr_limit = fs;
 }

 #define uaccess_kernel()	(get_fs() == KERNEL_DS)

 #define __range_ok(addr, size) (size <= get_fs() && addr <= (get_fs() -size))

 #define access_ok(addr, size)	\
 	__range_ok((unsigned long)addr, (unsigned long)size)
 /*
  * 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	__get_user					\

 #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_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	__put_user					\

 #define __put_user(x, ptr)						\
 ({									\
 	long __pu_err = 0;						\
 	__put_user_err((x), (ptr), __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 */
	/* 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>

	#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);

	#define KERNEL_DS ((mm_segment_t) { ~0UL })
	#define USER_DS ((mm_segment_t) {TASK_SIZE - 1})

	#define get_fs() (current_thread_info()->addr_limit)
	#define user_addr_max get_fs

	static inline void set_fs(mm_segment_t fs)
	{
	current_thread_info()->addr_limit = fs;
	}

	#define uaccess_kernel() (get_fs() == KERNEL_DS)

	#define __range_ok(addr, size) (size <= get_fs() && addr <= (get_fs() -size))

	#define access_ok(addr, size) \
	__range_ok((unsigned long)addr, (unsigned long)size)
	/*
	* 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 __get_user \

	#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_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 __put_user \

	#define __put_user(x, ptr) \
	({ \
	long __pu_err = 0; \
	__put_user_err((x), (ptr), __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 */