uaccess.h 34.7 KB
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/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
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 * Copyright (C) 2007  Maciej W. Rozycki
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 * Copyright (C) 2014, Imagination Technologies Ltd.
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 */
#ifndef _ASM_UACCESS_H
#define _ASM_UACCESS_H

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/thread_info.h>
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#include <asm/asm-eva.h>
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/*
 * The fs value determines whether argument validity checking should be
 * performed or not.  If get_fs() == USER_DS, checking is performed, with
 * get_fs() == KERNEL_DS, checking is bypassed.
 *
 * For historical reasons, these macros are grossly misnamed.
 */
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#ifdef CONFIG_32BIT
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#ifdef CONFIG_KVM_GUEST
#define __UA_LIMIT 0x40000000UL
#else
#define __UA_LIMIT 0x80000000UL
#endif
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#define __UA_ADDR	".word"
#define __UA_LA		"la"
#define __UA_ADDU	"addu"
#define __UA_t0		"$8"
#define __UA_t1		"$9"

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#endif /* CONFIG_32BIT */
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#ifdef CONFIG_64BIT
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extern u64 __ua_limit;

#define __UA_LIMIT	__ua_limit
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#define __UA_ADDR	".dword"
#define __UA_LA		"dla"
#define __UA_ADDU	"daddu"
#define __UA_t0		"$12"
#define __UA_t1		"$13"

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#endif /* CONFIG_64BIT */
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/*
 * USER_DS is a bitmask that has the bits set that may not be set in a valid
 * userspace address.  Note that we limit 32-bit userspace to 0x7fff8000 but
 * the arithmetic we're doing only works if the limit is a power of two, so
 * we use 0x80000000 here on 32-bit kernels.  If a process passes an invalid
 * address in this range it's the process's problem, not ours :-)
 */

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#ifdef CONFIG_KVM_GUEST
#define KERNEL_DS	((mm_segment_t) { 0x80000000UL })
#define USER_DS		((mm_segment_t) { 0xC0000000UL })
#else
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#define KERNEL_DS	((mm_segment_t) { 0UL })
#define USER_DS		((mm_segment_t) { __UA_LIMIT })
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#endif
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#define VERIFY_READ    0
#define VERIFY_WRITE   1

#define get_ds()	(KERNEL_DS)
#define get_fs()	(current_thread_info()->addr_limit)
#define set_fs(x)	(current_thread_info()->addr_limit = (x))

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#define segment_eq(a, b)	((a).seg == (b).seg)
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/*
 * Is a address valid? This does a straighforward calculation rather
 * than tests.
 *
 * Address valid if:
 *  - "addr" doesn't have any high-bits set
 *  - AND "size" doesn't have any high-bits set
 *  - AND "addr+size" doesn't have any high-bits set
 *  - OR we are in kernel mode.
 *
 * __ua_size() is a trick to avoid runtime checking of positive constant
 * sizes; for those we already know at compile time that the size is ok.
 */
#define __ua_size(size)							\
	((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))

/*
 * access_ok: - Checks if a user space pointer is valid
 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that
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 *	  %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
 *	  to write to a block, it is always safe to read from it.
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 * @addr: User space pointer to start of block to check
 * @size: Size of block to check
 *
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 * Context: User context only.	This function may sleep.
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 *
 * Checks if a pointer to a block of memory in user space is valid.
 *
 * Returns true (nonzero) if the memory block may be valid, false (zero)
 * if it is definitely invalid.
 *
 * Note that, depending on architecture, this function probably just
 * checks that the pointer is in the user space range - after calling
 * this function, memory access functions may still return -EFAULT.
 */

#define __access_mask get_fs().seg

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#define __access_ok(addr, size, mask)					\
({									\
	unsigned long __addr = (unsigned long) (addr);			\
	unsigned long __size = size;					\
	unsigned long __mask = mask;					\
	unsigned long __ok;						\
									\
	__chk_user_ptr(addr);						\
	__ok = (signed long)(__mask & (__addr | (__addr + __size) |	\
		__ua_size(__size)));					\
	__ok == 0;							\
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})
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#define access_ok(type, addr, size)					\
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	likely(__access_ok((addr), (size), __access_mask))
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/*
 * put_user: - Write a simple value into user space.
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 * @x:	 Value to copy to user space.
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 * @ptr: Destination address, in user space.
 *
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 * Context: User context only.	This function may sleep.
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 *
 * This macro copies a single simple value from kernel space to user
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 * to the result of dereferencing @ptr.
 *
 * Returns zero on success, or -EFAULT on error.
 */
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#define put_user(x,ptr) \
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	__put_user_check((x), (ptr), sizeof(*(ptr)))
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/*
 * get_user: - Get a simple variable from user space.
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 * @x:	 Variable to store result.
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 * @ptr: Source address, in user space.
 *
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 * Context: User context only.	This function may sleep.
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 *
 * This macro copies a single simple variable from user space to kernel
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and the result of
 * dereferencing @ptr must be assignable to @x without a cast.
 *
 * Returns zero on success, or -EFAULT on error.
 * On error, the variable @x is set to zero.
 */
#define get_user(x,ptr) \
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	__get_user_check((x), (ptr), sizeof(*(ptr)))
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/*
 * __put_user: - Write a simple value into user space, with less checking.
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 * @x:	 Value to copy to user space.
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 * @ptr: Destination address, in user space.
 *
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 * Context: User context only.	This function may sleep.
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 *
 * This macro copies a single simple value from kernel space to user
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 * to the result of dereferencing @ptr.
 *
 * Caller must check the pointer with access_ok() before calling this
 * function.
 *
 * Returns zero on success, or -EFAULT on error.
 */
#define __put_user(x,ptr) \
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	__put_user_nocheck((x), (ptr), sizeof(*(ptr)))
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/*
 * __get_user: - Get a simple variable from user space, with less checking.
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 * @x:	 Variable to store result.
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 * @ptr: Source address, in user space.
 *
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 * Context: User context only.	This function may sleep.
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 *
 * This macro copies a single simple variable from user space to kernel
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and the result of
 * dereferencing @ptr must be assignable to @x without a cast.
 *
 * Caller must check the pointer with access_ok() before calling this
 * function.
 *
 * Returns zero on success, or -EFAULT on error.
 * On error, the variable @x is set to zero.
 */
#define __get_user(x,ptr) \
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	__get_user_nocheck((x), (ptr), sizeof(*(ptr)))
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struct __large_struct { unsigned long buf[100]; };
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#define __m(x) (*(struct __large_struct __user *)(x))
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/*
 * Yuck.  We need two variants, one for 64bit operation and one
 * for 32 bit mode and old iron.
 */
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#ifndef CONFIG_EVA
#define __get_kernel_common(val, size, ptr) __get_user_common(val, size, ptr)
#else
/*
 * Kernel specific functions for EVA. We need to use normal load instructions
 * to read data from kernel when operating in EVA mode. We use these macros to
 * avoid redefining __get_user_asm for EVA.
 */
#undef _loadd
#undef _loadw
#undef _loadh
#undef _loadb
#ifdef CONFIG_32BIT
#define _loadd			_loadw
#else
#define _loadd(reg, addr)	"ld " reg ", " addr
#endif
#define _loadw(reg, addr)	"lw " reg ", " addr
#define _loadh(reg, addr)	"lh " reg ", " addr
#define _loadb(reg, addr)	"lb " reg ", " addr

#define __get_kernel_common(val, size, ptr)				\
do {									\
	switch (size) {							\
	case 1: __get_user_asm(val, _loadb, ptr); break;		\
	case 2: __get_user_asm(val, _loadh, ptr); break;		\
	case 4: __get_user_asm(val, _loadw, ptr); break;		\
	case 8: __GET_USER_DW(val, _loadd, ptr); break;			\
	default: __get_user_unknown(); break;				\
	}								\
} while (0)
#endif

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#ifdef CONFIG_32BIT
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#define __GET_USER_DW(val, insn, ptr) __get_user_asm_ll32(val, insn, ptr)
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#endif
#ifdef CONFIG_64BIT
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#define __GET_USER_DW(val, insn, ptr) __get_user_asm(val, insn, ptr)
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#endif

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extern void __get_user_unknown(void);

#define __get_user_common(val, size, ptr)				\
do {									\
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	switch (size) {							\
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	case 1: __get_user_asm(val, user_lb, ptr); break;		\
	case 2: __get_user_asm(val, user_lh, ptr); break;		\
	case 4: __get_user_asm(val, user_lw, ptr); break;		\
	case 8: __GET_USER_DW(val, user_ld, ptr); break;		\
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	default: __get_user_unknown(); break;				\
	}								\
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} while (0)

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#define __get_user_nocheck(x, ptr, size)				\
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({									\
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	int __gu_err;							\
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									\
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	if (segment_eq(get_fs(), get_ds())) {				\
		__get_kernel_common((x), size, ptr);			\
	} else {							\
		__chk_user_ptr(ptr);					\
		__get_user_common((x), size, ptr);			\
	}								\
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	__gu_err;							\
})

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#define __get_user_check(x, ptr, size)					\
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({									\
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	int __gu_err = -EFAULT;						\
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	const __typeof__(*(ptr)) __user * __gu_ptr = (ptr);		\
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									\
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	might_fault();							\
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	if (likely(access_ok(VERIFY_READ,  __gu_ptr, size))) {		\
		if (segment_eq(get_fs(), get_ds()))			\
			__get_kernel_common((x), size, __gu_ptr);	\
		else							\
			__get_user_common((x), size, __gu_ptr);		\
	}								\
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									\
	__gu_err;							\
})

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#define __get_user_asm(val, insn, addr)					\
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{									\
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	long __gu_tmp;							\
									\
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	__asm__ __volatile__(						\
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	"1:	"insn("%1", "%3")"				\n"	\
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	"2:							\n"	\
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	"	.insn						\n"	\
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	"	.section .fixup,\"ax\"				\n"	\
	"3:	li	%0, %4					\n"	\
	"	j	2b					\n"	\
	"	.previous					\n"	\
	"	.section __ex_table,\"a\"			\n"	\
	"	"__UA_ADDR "\t1b, 3b				\n"	\
	"	.previous					\n"	\
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	: "=r" (__gu_err), "=r" (__gu_tmp)				\
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	: "0" (0), "o" (__m(addr)), "i" (-EFAULT));			\
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									\
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	(val) = (__typeof__(*(addr))) __gu_tmp;				\
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}
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/*
 * Get a long long 64 using 32 bit registers.
 */
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#define __get_user_asm_ll32(val, insn, addr)				\
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{									\
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	union {								\
		unsigned long long	l;				\
		__typeof__(*(addr))	t;				\
	} __gu_tmp;							\
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									\
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	__asm__ __volatile__(						\
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	"1:	" insn("%1", "(%3)")"				\n"	\
	"2:	" insn("%D1", "4(%3)")"				\n"	\
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	"3:							\n"	\
	"	.insn						\n"	\
	"	.section	.fixup,\"ax\"			\n"	\
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	"4:	li	%0, %4					\n"	\
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	"	move	%1, $0					\n"	\
	"	move	%D1, $0					\n"	\
	"	j	3b					\n"	\
	"	.previous					\n"	\
	"	.section	__ex_table,\"a\"		\n"	\
	"	" __UA_ADDR "	1b, 4b				\n"	\
	"	" __UA_ADDR "	2b, 4b				\n"	\
	"	.previous					\n"	\
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	: "=r" (__gu_err), "=&r" (__gu_tmp.l)				\
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	: "0" (0), "r" (addr), "i" (-EFAULT));				\
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									\
	(val) = __gu_tmp.t;						\
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}
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#ifndef CONFIG_EVA
#define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
#else
/*
 * Kernel specific functions for EVA. We need to use normal load instructions
 * to read data from kernel when operating in EVA mode. We use these macros to
 * avoid redefining __get_user_asm for EVA.
 */
#undef _stored
#undef _storew
#undef _storeh
#undef _storeb
#ifdef CONFIG_32BIT
#define _stored			_storew
#else
#define _stored(reg, addr)	"ld " reg ", " addr
#endif

#define _storew(reg, addr)	"sw " reg ", " addr
#define _storeh(reg, addr)	"sh " reg ", " addr
#define _storeb(reg, addr)	"sb " reg ", " addr

#define __put_kernel_common(ptr, size)					\
do {									\
	switch (size) {							\
	case 1: __put_user_asm(_storeb, ptr); break;			\
	case 2: __put_user_asm(_storeh, ptr); break;			\
	case 4: __put_user_asm(_storew, ptr); break;			\
	case 8: __PUT_USER_DW(_stored, ptr); break;			\
	default: __put_user_unknown(); break;				\
	}								\
} while(0)
#endif

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/*
 * Yuck.  We need two variants, one for 64bit operation and one
 * for 32 bit mode and old iron.
 */
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#ifdef CONFIG_32BIT
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#define __PUT_USER_DW(insn, ptr) __put_user_asm_ll32(insn, ptr)
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#endif
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#ifdef CONFIG_64BIT
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#define __PUT_USER_DW(insn, ptr) __put_user_asm(insn, ptr)
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#endif
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#define __put_user_common(ptr, size)					\
do {									\
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	switch (size) {							\
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	case 1: __put_user_asm(user_sb, ptr); break;			\
	case 2: __put_user_asm(user_sh, ptr); break;			\
	case 4: __put_user_asm(user_sw, ptr); break;			\
	case 8: __PUT_USER_DW(user_sd, ptr); break;			\
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	default: __put_user_unknown(); break;				\
	}								\
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} while (0)

#define __put_user_nocheck(x, ptr, size)				\
({									\
	__typeof__(*(ptr)) __pu_val;					\
	int __pu_err = 0;						\
									\
	__pu_val = (x);							\
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	if (segment_eq(get_fs(), get_ds())) {				\
		__put_kernel_common(ptr, size);				\
	} else {							\
		__chk_user_ptr(ptr);					\
		__put_user_common(ptr, size);				\
	}								\
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	__pu_err;							\
})

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#define __put_user_check(x, ptr, size)					\
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({									\
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	__typeof__(*(ptr)) __user *__pu_addr = (ptr);			\
	__typeof__(*(ptr)) __pu_val = (x);				\
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	int __pu_err = -EFAULT;						\
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									\
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	might_fault();							\
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	if (likely(access_ok(VERIFY_WRITE,  __pu_addr, size))) {	\
		if (segment_eq(get_fs(), get_ds()))			\
			__put_kernel_common(__pu_addr, size);		\
		else							\
			__put_user_common(__pu_addr, size);		\
	}								\
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									\
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	__pu_err;							\
})

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#define __put_user_asm(insn, ptr)					\
{									\
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	__asm__ __volatile__(						\
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	"1:	"insn("%z2", "%3")"	# __put_user_asm	\n"	\
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	"2:							\n"	\
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	"	.insn						\n"	\
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	"	.section	.fixup,\"ax\"			\n"	\
	"3:	li	%0, %4					\n"	\
	"	j	2b					\n"	\
	"	.previous					\n"	\
	"	.section	__ex_table,\"a\"		\n"	\
	"	" __UA_ADDR "	1b, 3b				\n"	\
	"	.previous					\n"	\
	: "=r" (__pu_err)						\
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	: "0" (0), "Jr" (__pu_val), "o" (__m(ptr)),			\
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	  "i" (-EFAULT));						\
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}
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#define __put_user_asm_ll32(insn, ptr)					\
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{									\
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	__asm__ __volatile__(						\
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	"1:	"insn("%2", "(%3)")"	# __put_user_asm_ll32	\n"	\
	"2:	"insn("%D2", "4(%3)")"				\n"	\
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	"3:							\n"	\
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	"	.insn						\n"	\
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	"	.section	.fixup,\"ax\"			\n"	\
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	"4:	li	%0, %4					\n"	\
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	"	j	3b					\n"	\
	"	.previous					\n"	\
	"	.section	__ex_table,\"a\"		\n"	\
	"	" __UA_ADDR "	1b, 4b				\n"	\
	"	" __UA_ADDR "	2b, 4b				\n"	\
	"	.previous"						\
	: "=r" (__pu_err)						\
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	: "0" (0), "r" (__pu_val), "r" (ptr),				\
	  "i" (-EFAULT));						\
}
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extern void __put_user_unknown(void);

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/*
 * ul{b,h,w} are macros and there are no equivalent macros for EVA.
 * EVA unaligned access is handled in the ADE exception handler.
 */
#ifndef CONFIG_EVA
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/*
 * put_user_unaligned: - Write a simple value into user space.
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 * @x:	 Value to copy to user space.
497 498
 * @ptr: Destination address, in user space.
 *
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 * Context: User context only.	This function may sleep.
500 501 502 503 504 505 506 507 508 509 510 511 512 513 514
 *
 * This macro copies a single simple value from kernel space to user
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 * to the result of dereferencing @ptr.
 *
 * Returns zero on success, or -EFAULT on error.
 */
#define put_user_unaligned(x,ptr)	\
	__put_user_unaligned_check((x),(ptr),sizeof(*(ptr)))

/*
 * get_user_unaligned: - Get a simple variable from user space.
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 * @x:	 Variable to store result.
516 517
 * @ptr: Source address, in user space.
 *
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 * Context: User context only.	This function may sleep.
519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534
 *
 * This macro copies a single simple variable from user space to kernel
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and the result of
 * dereferencing @ptr must be assignable to @x without a cast.
 *
 * Returns zero on success, or -EFAULT on error.
 * On error, the variable @x is set to zero.
 */
#define get_user_unaligned(x,ptr) \
	__get_user_unaligned_check((x),(ptr),sizeof(*(ptr)))

/*
 * __put_user_unaligned: - Write a simple value into user space, with less checking.
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 * @x:	 Value to copy to user space.
536 537
 * @ptr: Destination address, in user space.
 *
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 * Context: User context only.	This function may sleep.
539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556
 *
 * This macro copies a single simple value from kernel space to user
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 * to the result of dereferencing @ptr.
 *
 * Caller must check the pointer with access_ok() before calling this
 * function.
 *
 * Returns zero on success, or -EFAULT on error.
 */
#define __put_user_unaligned(x,ptr) \
	__put_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))

/*
 * __get_user_unaligned: - Get a simple variable from user space, with less checking.
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 * @x:	 Variable to store result.
558 559
 * @ptr: Source address, in user space.
 *
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 * Context: User context only.	This function may sleep.
561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629
 *
 * This macro copies a single simple variable from user space to kernel
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and the result of
 * dereferencing @ptr must be assignable to @x without a cast.
 *
 * Caller must check the pointer with access_ok() before calling this
 * function.
 *
 * Returns zero on success, or -EFAULT on error.
 * On error, the variable @x is set to zero.
 */
#define __get_user_unaligned(x,ptr) \
	__get_user__unalignednocheck((x),(ptr),sizeof(*(ptr)))

/*
 * Yuck.  We need two variants, one for 64bit operation and one
 * for 32 bit mode and old iron.
 */
#ifdef CONFIG_32BIT
#define __GET_USER_UNALIGNED_DW(val, ptr)				\
	__get_user_unaligned_asm_ll32(val, ptr)
#endif
#ifdef CONFIG_64BIT
#define __GET_USER_UNALIGNED_DW(val, ptr)				\
	__get_user_unaligned_asm(val, "uld", ptr)
#endif

extern void __get_user_unaligned_unknown(void);

#define __get_user_unaligned_common(val, size, ptr)			\
do {									\
	switch (size) {							\
	case 1: __get_user_asm(val, "lb", ptr); break;			\
	case 2: __get_user_unaligned_asm(val, "ulh", ptr); break;	\
	case 4: __get_user_unaligned_asm(val, "ulw", ptr); break;	\
	case 8: __GET_USER_UNALIGNED_DW(val, ptr); break;		\
	default: __get_user_unaligned_unknown(); break;			\
	}								\
} while (0)

#define __get_user_unaligned_nocheck(x,ptr,size)			\
({									\
	int __gu_err;							\
									\
	__get_user_unaligned_common((x), size, ptr);			\
	__gu_err;							\
})

#define __get_user_unaligned_check(x,ptr,size)				\
({									\
	int __gu_err = -EFAULT;						\
	const __typeof__(*(ptr)) __user * __gu_ptr = (ptr);		\
									\
	if (likely(access_ok(VERIFY_READ,  __gu_ptr, size)))		\
		__get_user_unaligned_common((x), size, __gu_ptr);	\
									\
	__gu_err;							\
})

#define __get_user_unaligned_asm(val, insn, addr)			\
{									\
	long __gu_tmp;							\
									\
	__asm__ __volatile__(						\
	"1:	" insn "	%1, %3				\n"	\
	"2:							\n"	\
630
	"	.insn						\n"	\
631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649
	"	.section .fixup,\"ax\"				\n"	\
	"3:	li	%0, %4					\n"	\
	"	j	2b					\n"	\
	"	.previous					\n"	\
	"	.section __ex_table,\"a\"			\n"	\
	"	"__UA_ADDR "\t1b, 3b				\n"	\
	"	"__UA_ADDR "\t1b + 4, 3b			\n"	\
	"	.previous					\n"	\
	: "=r" (__gu_err), "=r" (__gu_tmp)				\
	: "0" (0), "o" (__m(addr)), "i" (-EFAULT));			\
									\
	(val) = (__typeof__(*(addr))) __gu_tmp;				\
}

/*
 * Get a long long 64 using 32 bit registers.
 */
#define __get_user_unaligned_asm_ll32(val, addr)			\
{									\
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	unsigned long long __gu_tmp;					\
651 652 653 654 655
									\
	__asm__ __volatile__(						\
	"1:	ulw	%1, (%3)				\n"	\
	"2:	ulw	%D1, 4(%3)				\n"	\
	"	move	%0, $0					\n"	\
656 657 658
	"3:							\n"	\
	"	.insn						\n"	\
	"	.section	.fixup,\"ax\"			\n"	\
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	"4:	li	%0, %4					\n"	\
	"	move	%1, $0					\n"	\
	"	move	%D1, $0					\n"	\
	"	j	3b					\n"	\
	"	.previous					\n"	\
	"	.section	__ex_table,\"a\"		\n"	\
	"	" __UA_ADDR "	1b, 4b				\n"	\
	"	" __UA_ADDR "	1b + 4, 4b			\n"	\
	"	" __UA_ADDR "	2b, 4b				\n"	\
	"	" __UA_ADDR "	2b + 4, 4b			\n"	\
	"	.previous					\n"	\
	: "=r" (__gu_err), "=&r" (__gu_tmp)				\
	: "0" (0), "r" (addr), "i" (-EFAULT));				\
	(val) = (__typeof__(*(addr))) __gu_tmp;				\
}

/*
 * Yuck.  We need two variants, one for 64bit operation and one
 * for 32 bit mode and old iron.
 */
#ifdef CONFIG_32BIT
#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm_ll32(ptr)
#endif
#ifdef CONFIG_64BIT
#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm("usd", ptr)
#endif

686 687
#define __put_user_unaligned_common(ptr, size)				\
do {									\
688 689 690 691 692 693
	switch (size) {							\
	case 1: __put_user_asm("sb", ptr); break;			\
	case 2: __put_user_unaligned_asm("ush", ptr); break;		\
	case 4: __put_user_unaligned_asm("usw", ptr); break;		\
	case 8: __PUT_USER_UNALIGNED_DW(ptr); break;			\
	default: __put_user_unaligned_unknown(); break;			\
694 695 696 697 698 699 700 701 702
} while (0)

#define __put_user_unaligned_nocheck(x,ptr,size)			\
({									\
	__typeof__(*(ptr)) __pu_val;					\
	int __pu_err = 0;						\
									\
	__pu_val = (x);							\
	__put_user_unaligned_common(ptr, size);				\
703 704 705 706 707 708 709 710 711
	__pu_err;							\
})

#define __put_user_unaligned_check(x,ptr,size)				\
({									\
	__typeof__(*(ptr)) __user *__pu_addr = (ptr);			\
	__typeof__(*(ptr)) __pu_val = (x);				\
	int __pu_err = -EFAULT;						\
									\
712 713 714
	if (likely(access_ok(VERIFY_WRITE,  __pu_addr, size)))		\
		__put_user_unaligned_common(__pu_addr, size);		\
									\
715 716 717 718 719 720 721 722
	__pu_err;							\
})

#define __put_user_unaligned_asm(insn, ptr)				\
{									\
	__asm__ __volatile__(						\
	"1:	" insn "	%z2, %3		# __put_user_unaligned_asm\n" \
	"2:							\n"	\
723
	"	.insn						\n"	\
724 725 726 727 728 729 730 731 732 733 734 735 736 737 738
	"	.section	.fixup,\"ax\"			\n"	\
	"3:	li	%0, %4					\n"	\
	"	j	2b					\n"	\
	"	.previous					\n"	\
	"	.section	__ex_table,\"a\"		\n"	\
	"	" __UA_ADDR "	1b, 3b				\n"	\
	"	.previous					\n"	\
	: "=r" (__pu_err)						\
	: "0" (0), "Jr" (__pu_val), "o" (__m(ptr)),			\
	  "i" (-EFAULT));						\
}

#define __put_user_unaligned_asm_ll32(ptr)				\
{									\
	__asm__ __volatile__(						\
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	"1:	sw	%2, (%3)	# __put_user_unaligned_asm_ll32 \n" \
740 741
	"2:	sw	%D2, 4(%3)				\n"	\
	"3:							\n"	\
742
	"	.insn						\n"	\
743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758
	"	.section	.fixup,\"ax\"			\n"	\
	"4:	li	%0, %4					\n"	\
	"	j	3b					\n"	\
	"	.previous					\n"	\
	"	.section	__ex_table,\"a\"		\n"	\
	"	" __UA_ADDR "	1b, 4b				\n"	\
	"	" __UA_ADDR "	1b + 4, 4b			\n"	\
	"	" __UA_ADDR "	2b, 4b				\n"	\
	"	" __UA_ADDR "	2b + 4, 4b			\n"	\
	"	.previous"						\
	: "=r" (__pu_err)						\
	: "0" (0), "r" (__pu_val), "r" (ptr),				\
	  "i" (-EFAULT));						\
}

extern void __put_user_unaligned_unknown(void);
759
#endif
760

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/*
 * We're generating jump to subroutines which will be outside the range of
 * jump instructions
 */
#ifdef MODULE
#define __MODULE_JAL(destination)					\
	".set\tnoat\n\t"						\
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	__UA_LA "\t$1, " #destination "\n\t"				\
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	"jalr\t$1\n\t"							\
	".set\tat\n\t"
#else
#define __MODULE_JAL(destination)					\
	"jal\t" #destination "\n\t"
#endif

776 777 778 779 780 781
#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
#define DADDI_SCRATCH "$0"
#else
#define DADDI_SCRATCH "$3"
#endif

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extern size_t __copy_user(void *__to, const void *__from, size_t __n);

784
#define __invoke_copy_to_user(to, from, n)				\
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({									\
786 787 788
	register void __user *__cu_to_r __asm__("$4");			\
	register const void *__cu_from_r __asm__("$5");			\
	register long __cu_len_r __asm__("$6");				\
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									\
	__cu_to_r = (to);						\
	__cu_from_r = (from);						\
	__cu_len_r = (n);						\
	__asm__ __volatile__(						\
	__MODULE_JAL(__copy_user)					\
	: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)	\
	:								\
797
	: "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",	\
798
	  DADDI_SCRATCH, "memory");					\
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	__cu_len_r;							\
})

/*
 * __copy_to_user: - Copy a block of data into user space, with less checking.
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 * @to:	  Destination address, in user space.
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 * @from: Source address, in kernel space.
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 * @n:	  Number of bytes to copy.
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 *
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 * Context: User context only.	This function may sleep.
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 *
 * Copy data from kernel space to user space.  Caller must check
 * the specified block with access_ok() before calling this function.
 *
 * Returns number of bytes that could not be copied.
 * On success, this will be zero.
 */
816
#define __copy_to_user(to, from, n)					\
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({									\
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	void __user *__cu_to;						\
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	const void *__cu_from;						\
	long __cu_len;							\
									\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
825
	might_fault();							\
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	__cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
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	__cu_len;							\
})

830 831
extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);

832
#define __copy_to_user_inatomic(to, from, n)				\
833 834 835 836 837 838 839 840
({									\
	void __user *__cu_to;						\
	const void *__cu_from;						\
	long __cu_len;							\
									\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
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	__cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
842 843 844
	__cu_len;							\
})

845
#define __copy_from_user_inatomic(to, from, n)				\
846 847 848 849 850 851 852 853
({									\
	void *__cu_to;							\
	const void __user *__cu_from;					\
	long __cu_len;							\
									\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
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	__cu_len = __invoke_copy_from_user_inatomic(__cu_to, __cu_from, \
						    __cu_len);		\
856 857
	__cu_len;							\
})
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/*
 * copy_to_user: - Copy a block of data into user space.
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 * @to:	  Destination address, in user space.
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 * @from: Source address, in kernel space.
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 * @n:	  Number of bytes to copy.
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 *
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 * Context: User context only.	This function may sleep.
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 *
 * Copy data from kernel space to user space.
 *
 * Returns number of bytes that could not be copied.
 * On success, this will be zero.
 */
872
#define copy_to_user(to, from, n)					\
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({									\
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	void __user *__cu_to;						\
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	const void *__cu_from;						\
	long __cu_len;							\
									\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
881 882
	if (access_ok(VERIFY_WRITE, __cu_to, __cu_len)) {		\
		might_fault();						\
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		__cu_len = __invoke_copy_to_user(__cu_to, __cu_from,	\
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						 __cu_len);		\
885
	}								\
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	__cu_len;							\
})

889
#define __invoke_copy_from_user(to, from, n)				\
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({									\
891 892 893
	register void *__cu_to_r __asm__("$4");				\
	register const void __user *__cu_from_r __asm__("$5");		\
	register long __cu_len_r __asm__("$6");				\
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									\
	__cu_to_r = (to);						\
	__cu_from_r = (from);						\
	__cu_len_r = (n);						\
	__asm__ __volatile__(						\
	".set\tnoreorder\n\t"						\
	__MODULE_JAL(__copy_user)					\
	".set\tnoat\n\t"						\
	__UA_ADDU "\t$1, %1, %2\n\t"					\
	".set\tat\n\t"							\
	".set\treorder"							\
	: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)	\
	:								\
907
	: "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",	\
908
	  DADDI_SCRATCH, "memory");					\
909 910 911
	__cu_len_r;							\
})

912
#define __invoke_copy_from_user_inatomic(to, from, n)			\
913
({									\
914 915 916
	register void *__cu_to_r __asm__("$4");				\
	register const void __user *__cu_from_r __asm__("$5");		\
	register long __cu_len_r __asm__("$6");				\
917 918 919 920 921 922 923 924 925 926 927 928 929
									\
	__cu_to_r = (to);						\
	__cu_from_r = (from);						\
	__cu_len_r = (n);						\
	__asm__ __volatile__(						\
	".set\tnoreorder\n\t"						\
	__MODULE_JAL(__copy_user_inatomic)				\
	".set\tnoat\n\t"						\
	__UA_ADDU "\t$1, %1, %2\n\t"					\
	".set\tat\n\t"							\
	".set\treorder"							\
	: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)	\
	:								\
930
	: "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",	\
931
	  DADDI_SCRATCH, "memory");					\
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	__cu_len_r;							\
})

/*
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 * __copy_from_user: - Copy a block of data from user space, with less checking.
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 * @to:	  Destination address, in kernel space.
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 * @from: Source address, in user space.
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 * @n:	  Number of bytes to copy.
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 *
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 * Context: User context only.	This function may sleep.
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 *
 * Copy data from user space to kernel space.  Caller must check
 * the specified block with access_ok() before calling this function.
 *
 * Returns number of bytes that could not be copied.
 * On success, this will be zero.
 *
 * If some data could not be copied, this function will pad the copied
 * data to the requested size using zero bytes.
 */
952
#define __copy_from_user(to, from, n)					\
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({									\
	void *__cu_to;							\
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	const void __user *__cu_from;					\
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	long __cu_len;							\
									\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
961
	might_fault();							\
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	__cu_len = __invoke_copy_from_user(__cu_to, __cu_from,		\
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					   __cu_len);			\
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	__cu_len;							\
})

/*
 * copy_from_user: - Copy a block of data from user space.
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 * @to:	  Destination address, in kernel space.
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 * @from: Source address, in user space.
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 * @n:	  Number of bytes to copy.
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 *
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 * Context: User context only.	This function may sleep.
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 *
 * Copy data from user space to kernel space.
 *
 * Returns number of bytes that could not be copied.
 * On success, this will be zero.
 *
 * If some data could not be copied, this function will pad the copied
 * data to the requested size using zero bytes.
 */
983
#define copy_from_user(to, from, n)					\
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({									\
	void *__cu_to;							\
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	const void __user *__cu_from;					\
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	long __cu_len;							\
									\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
992 993
	if (access_ok(VERIFY_READ, __cu_from, __cu_len)) {		\
		might_fault();						\
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		__cu_len = __invoke_copy_from_user(__cu_to, __cu_from,	\
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						   __cu_len);		\
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	}								\
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	__cu_len;							\
})

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#define __copy_in_user(to, from, n)					\
({									\
	void __user *__cu_to;						\
	const void __user *__cu_from;					\
	long __cu_len;							\
									\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
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	might_fault();							\
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	__cu_len = __invoke_copy_from_user(__cu_to, __cu_from,		\
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					   __cu_len);			\
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	__cu_len;							\
})
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#define copy_in_user(to, from, n)					\
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({									\
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	void __user *__cu_to;						\
	const void __user *__cu_from;					\
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	long __cu_len;							\
									\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
	if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) &&	\
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		   access_ok(VERIFY_WRITE, __cu_to, __cu_len))) {	\
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		might_fault();						\
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		__cu_len = __invoke_copy_from_user(__cu_to, __cu_from,	\
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						   __cu_len);		\
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	}								\
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	__cu_len;							\
})

/*
 * __clear_user: - Zero a block of memory in user space, with less checking.
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 * @to:	  Destination address, in user space.
 * @n:	  Number of bytes to zero.
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 *
 * Zero a block of memory in user space.  Caller must check
 * the specified block with access_ok() before calling this function.
 *
 * Returns number of bytes that could not be cleared.
 * On success, this will be zero.
 */
static inline __kernel_size_t
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__clear_user(void __user *addr, __kernel_size_t size)
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{
	__kernel_size_t res;

1049
	might_fault();
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	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, $0\n\t"
		"move\t$6, %2\n\t"
		__MODULE_JAL(__bzero)
		"move\t%0, $6"
		: "=r" (res)
		: "r" (addr), "r" (size)
		: "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");

	return res;
}

#define clear_user(addr,n)						\
({									\
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	void __user * __cl_addr = (addr);				\
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	unsigned long __cl_size = (n);					\
	if (__cl_size && access_ok(VERIFY_WRITE,			\
1068
					__cl_addr, __cl_size))		\
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		__cl_size = __clear_user(__cl_addr, __cl_size);		\
	__cl_size;							\
})

/*
 * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
 * @dst:   Destination address, in kernel space.  This buffer must be at
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 *	   least @count bytes long.
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 * @src:   Source address, in user space.
 * @count: Maximum number of bytes to copy, including the trailing NUL.
 *
 * Copies a NUL-terminated string from userspace to kernel space.
 * Caller must check the specified block with access_ok() before calling
 * this function.
 *
 * On success, returns the length of the string (not including the trailing
 * NUL).
 *
 * If access to userspace fails, returns -EFAULT (some data may have been
 * copied).
 *
 * If @count is smaller than the length of the string, copies @count bytes
 * and returns @count.
 */
static inline long
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__strncpy_from_user(char *__to, const char __user *__from, long __len)
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{
	long res;

1098
	might_fault();
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	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, %2\n\t"
		"move\t$6, %3\n\t"
		__MODULE_JAL(__strncpy_from_user_nocheck_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (__to), "r" (__from), "r" (__len)
		: "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");

	return res;
}

/*
 * strncpy_from_user: - Copy a NUL terminated string from userspace.
 * @dst:   Destination address, in kernel space.  This buffer must be at
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 *	   least @count bytes long.
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 * @src:   Source address, in user space.
 * @count: Maximum number of bytes to copy, including the trailing NUL.
 *
 * Copies a NUL-terminated string from userspace to kernel space.
 *
 * On success, returns the length of the string (not including the trailing
 * NUL).
 *
 * If access to userspace fails, returns -EFAULT (some data may have been
 * copied).
 *
 * If @count is smaller than the length of the string, copies @count bytes
 * and returns @count.
 */
static inline long
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strncpy_from_user(char *__to, const char __user *__from, long __len)
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{
	long res;

1135
	might_fault();
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	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, %2\n\t"
		"move\t$6, %3\n\t"
		__MODULE_JAL(__strncpy_from_user_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (__to), "r" (__from), "r" (__len)
		: "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");

	return res;
}

/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
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static inline long __strlen_user(const char __user *s)
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{
	long res;

1154
	might_fault();
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	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		__MODULE_JAL(__strlen_user_nocheck_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (s)
		: "$2", "$4", __UA_t0, "$31");

	return res;
}

/*
 * strlen_user: - Get the size of a string in user space.
 * @str: The string to measure.
 *
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 * Context: User context only.	This function may sleep.
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 *
 * Get the size of a NUL-terminated string in user space.
 *
 * Returns the size of the string INCLUDING the terminating NUL.
 * On exception, returns 0.
 *
 * If there is a limit on the length of a valid string, you may wish to
 * consider using strnlen_user() instead.
 */
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static inline long strlen_user(const char __user *s)
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{
	long res;

1184
	might_fault();
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	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		__MODULE_JAL(__strlen_user_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (s)
		: "$2", "$4", __UA_t0, "$31");

	return res;
}

/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
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static inline long __strnlen_user(const char __user *s, long n)
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{
	long res;

1201
	might_fault();
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	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, %2\n\t"
		__MODULE_JAL(__strnlen_user_nocheck_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (s), "r" (n)
		: "$2", "$4", "$5", __UA_t0, "$31");

	return res;
}

/*
 * strlen_user: - Get the size of a string in user space.
 * @str: The string to measure.
 *
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 * Context: User context only.	This function may sleep.
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 *
 * Get the size of a NUL-terminated string in user space.
 *
 * Returns the size of the string INCLUDING the terminating NUL.
 * On exception, returns 0.
 *
 * If there is a limit on the length of a valid string, you may wish to
 * consider using strnlen_user() instead.
 */
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static inline long strnlen_user(const char __user *s, long n)
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{
	long res;

1232
	might_fault();
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	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, %2\n\t"
		__MODULE_JAL(__strnlen_user_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (s), "r" (n)
		: "$2", "$4", "$5", __UA_t0, "$31");

	return res;
}

struct exception_table_entry
{
	unsigned long insn;
	unsigned long nextinsn;
};

extern int fixup_exception(struct pt_regs *regs);

#endif /* _ASM_UACCESS_H */