565 lines
15 KiB
C
565 lines
15 KiB
C
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/*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
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* 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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*/
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#ifndef _ASM_UACCESS_H
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#define _ASM_UACCESS_H
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <asm/asm-eva.h>
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#include <asm/extable.h>
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#ifdef CONFIG_32BIT
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#define __UA_LIMIT 0x80000000UL
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#define TASK_SIZE_MAX KSEG0
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#define __UA_ADDR ".word"
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#define __UA_LA "la"
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#define __UA_ADDU "addu"
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#define __UA_t0 "$8"
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#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;
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#define __UA_LIMIT __ua_limit
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#define TASK_SIZE_MAX XKSSEG
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#define __UA_ADDR ".dword"
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#define __UA_LA "dla"
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#define __UA_ADDU "daddu"
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#define __UA_t0 "$12"
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#define __UA_t1 "$13"
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#endif /* CONFIG_64BIT */
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#include <asm-generic/access_ok.h>
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/*
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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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*
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* Context: User context only. This function may sleep if pagefaults are
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* enabled.
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*
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* This macro copies a single simple value from kernel space to user
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* space. It supports simple types like char and int, but not larger
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* data types like structures or arrays.
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*
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* @ptr must have pointer-to-simple-variable type, and @x must be assignable
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* to the result of dereferencing @ptr.
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*
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* Returns zero on success, or -EFAULT on error.
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*/
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#define put_user(x, ptr) \
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({ \
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__typeof__(*(ptr)) __user *__p = (ptr); \
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\
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might_fault(); \
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access_ok(__p, sizeof(*__p)) ? __put_user((x), __p) : -EFAULT; \
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})
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/*
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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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*
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* Context: User context only. This function may sleep if pagefaults are
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* enabled.
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*
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* This macro copies a single simple variable from user space to kernel
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* space. It supports simple types like char and int, but not larger
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* data types like structures or arrays.
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*
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* @ptr must have pointer-to-simple-variable type, and the result of
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* dereferencing @ptr must be assignable to @x without a cast.
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*
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* Returns zero on success, or -EFAULT on error.
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* On error, the variable @x is set to zero.
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*/
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#define get_user(x, ptr) \
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({ \
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const __typeof__(*(ptr)) __user *__p = (ptr); \
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\
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might_fault(); \
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access_ok(__p, sizeof(*__p)) ? __get_user((x), __p) : \
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((x) = 0, -EFAULT); \
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})
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/*
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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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*
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* Context: User context only. This function may sleep if pagefaults are
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* enabled.
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*
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* This macro copies a single simple value from kernel space to user
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* space. It supports simple types like char and int, but not larger
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* data types like structures or arrays.
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*
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* @ptr must have pointer-to-simple-variable type, and @x must be assignable
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* to the result of dereferencing @ptr.
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*
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* Caller must check the pointer with access_ok() before calling this
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* function.
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*
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* Returns zero on success, or -EFAULT on error.
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*/
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#define __put_user(x, ptr) \
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({ \
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__typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
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__typeof__(*(ptr)) __pu_val = (x); \
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int __pu_err = 0; \
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\
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__chk_user_ptr(__pu_ptr); \
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switch (sizeof(*__pu_ptr)) { \
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case 1: \
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__put_data_asm(user_sb, __pu_ptr); \
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break; \
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case 2: \
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__put_data_asm(user_sh, __pu_ptr); \
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break; \
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case 4: \
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__put_data_asm(user_sw, __pu_ptr); \
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break; \
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case 8: \
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__PUT_DW(user_sd, __pu_ptr); \
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break; \
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default: \
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BUILD_BUG(); \
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} \
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\
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__pu_err; \
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})
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/*
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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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*
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* Context: User context only. This function may sleep if pagefaults are
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* enabled.
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*
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* This macro copies a single simple variable from user space to kernel
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* space. It supports simple types like char and int, but not larger
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* data types like structures or arrays.
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*
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* @ptr must have pointer-to-simple-variable type, and the result of
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* dereferencing @ptr must be assignable to @x without a cast.
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*
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* Caller must check the pointer with access_ok() before calling this
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* function.
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*
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* Returns zero on success, or -EFAULT on error.
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* On error, the variable @x is set to zero.
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*/
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#define __get_user(x, ptr) \
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({ \
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const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \
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int __gu_err = 0; \
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\
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__chk_user_ptr(__gu_ptr); \
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switch (sizeof(*__gu_ptr)) { \
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case 1: \
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__get_data_asm((x), user_lb, __gu_ptr); \
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break; \
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case 2: \
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__get_data_asm((x), user_lh, __gu_ptr); \
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break; \
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case 4: \
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__get_data_asm((x), user_lw, __gu_ptr); \
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break; \
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case 8: \
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__GET_DW((x), user_ld, __gu_ptr); \
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break; \
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default: \
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BUILD_BUG(); \
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} \
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\
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__gu_err; \
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})
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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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#ifdef CONFIG_32BIT
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#define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
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#endif
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#ifdef CONFIG_64BIT
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#define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr)
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#endif
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#define __get_data_asm(val, insn, addr) \
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{ \
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long __gu_tmp; \
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\
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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" \
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"3: li %0, %4 \n" \
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" move %1, $0 \n" \
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" j 2b \n" \
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" .previous \n" \
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" .section __ex_table,\"a\" \n" \
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" "__UA_ADDR "\t1b, 3b \n" \
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" .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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/*
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* Get a long long 64 using 32 bit registers.
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*/
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#define __get_data_asm_ll32(val, insn, addr) \
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{ \
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union { \
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unsigned long long l; \
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__typeof__(*(addr)) t; \
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} __gu_tmp; \
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\
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__asm__ __volatile__( \
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"1: " insn("%1", "(%3)")" \n" \
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"2: " insn("%D1", "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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" move %1, $0 \n" \
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" move %D1, $0 \n" \
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" j 3b \n" \
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" .previous \n" \
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" .section __ex_table,\"a\" \n" \
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" " __UA_ADDR " 1b, 4b \n" \
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" " __UA_ADDR " 2b, 4b \n" \
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" .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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\
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(val) = __gu_tmp.t; \
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}
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#define __get_kernel_nofault(dst, src, type, err_label) \
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do { \
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int __gu_err; \
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\
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switch (sizeof(type)) { \
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case 1: \
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__get_data_asm(*(type *)(dst), kernel_lb, \
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(__force type *)(src)); \
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break; \
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case 2: \
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__get_data_asm(*(type *)(dst), kernel_lh, \
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(__force type *)(src)); \
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break; \
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case 4: \
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__get_data_asm(*(type *)(dst), kernel_lw, \
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(__force type *)(src)); \
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break; \
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case 8: \
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__GET_DW(*(type *)(dst), kernel_ld, \
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(__force type *)(src)); \
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break; \
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default: \
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BUILD_BUG(); \
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break; \
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} \
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if (unlikely(__gu_err)) \
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goto err_label; \
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} while (0)
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/*
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* Yuck. We need two variants, one for 64bit operation and one
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* for 32 bit mode and old iron.
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*/
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#ifdef CONFIG_32BIT
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#define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr)
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#endif
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#ifdef CONFIG_64BIT
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#define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr)
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#endif
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#define __put_data_asm(insn, ptr) \
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{ \
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__asm__ __volatile__( \
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"1: "insn("%z2", "%3")" # __put_data_asm \n" \
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"2: \n" \
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" .insn \n" \
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" .section .fixup,\"ax\" \n" \
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"3: li %0, %4 \n" \
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" j 2b \n" \
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" .previous \n" \
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" .section __ex_table,\"a\" \n" \
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" " __UA_ADDR " 1b, 3b \n" \
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" .previous \n" \
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: "=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_data_asm_ll32(insn, ptr) \
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{ \
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__asm__ __volatile__( \
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"1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
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"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" \
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" .previous \n" \
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" .section __ex_table,\"a\" \n" \
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" " __UA_ADDR " 1b, 4b \n" \
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" " __UA_ADDR " 2b, 4b \n" \
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" .previous" \
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: "=r" (__pu_err) \
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: "0" (0), "r" (__pu_val), "r" (ptr), \
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"i" (-EFAULT)); \
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}
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#define __put_kernel_nofault(dst, src, type, err_label) \
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do { \
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type __pu_val; \
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int __pu_err = 0; \
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\
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__pu_val = *(__force type *)(src); \
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switch (sizeof(type)) { \
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case 1: \
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__put_data_asm(kernel_sb, (type *)(dst)); \
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break; \
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case 2: \
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__put_data_asm(kernel_sh, (type *)(dst)); \
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break; \
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case 4: \
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__put_data_asm(kernel_sw, (type *)(dst)) \
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break; \
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case 8: \
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__PUT_DW(kernel_sd, (type *)(dst)); \
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break; \
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default: \
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BUILD_BUG(); \
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break; \
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} \
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if (unlikely(__pu_err)) \
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goto err_label; \
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} while (0)
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/*
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* We're generating jump to subroutines which will be outside the range of
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* jump instructions
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*/
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#ifdef MODULE
|
||
|
|
#define __MODULE_JAL(destination) \
|
||
|
|
".set\tnoat\n\t" \
|
||
|
|
__UA_LA "\t$1, " #destination "\n\t" \
|
||
|
|
"jalr\t$1\n\t" \
|
||
|
|
".set\tat\n\t"
|
||
|
|
#else
|
||
|
|
#define __MODULE_JAL(destination) \
|
||
|
|
"jal\t" #destination "\n\t"
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) && \
|
||
|
|
defined(CONFIG_CPU_HAS_PREFETCH))
|
||
|
|
#define DADDI_SCRATCH "$3"
|
||
|
|
#else
|
||
|
|
#define DADDI_SCRATCH "$0"
|
||
|
|
#endif
|
||
|
|
|
||
|
|
extern size_t __raw_copy_from_user(void *__to, const void *__from, size_t __n);
|
||
|
|
extern size_t __raw_copy_to_user(void *__to, const void *__from, size_t __n);
|
||
|
|
|
||
|
|
static inline unsigned long
|
||
|
|
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
|
||
|
|
{
|
||
|
|
register void *__cu_to_r __asm__("$4");
|
||
|
|
register const void __user *__cu_from_r __asm__("$5");
|
||
|
|
register long __cu_len_r __asm__("$6");
|
||
|
|
|
||
|
|
__cu_to_r = to;
|
||
|
|
__cu_from_r = from;
|
||
|
|
__cu_len_r = n;
|
||
|
|
|
||
|
|
__asm__ __volatile__(
|
||
|
|
".set\tnoreorder\n\t"
|
||
|
|
__MODULE_JAL(__raw_copy_from_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)
|
||
|
|
:
|
||
|
|
: "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
|
||
|
|
DADDI_SCRATCH, "memory");
|
||
|
|
|
||
|
|
return __cu_len_r;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline unsigned long
|
||
|
|
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
|
||
|
|
{
|
||
|
|
register void __user *__cu_to_r __asm__("$4");
|
||
|
|
register const void *__cu_from_r __asm__("$5");
|
||
|
|
register long __cu_len_r __asm__("$6");
|
||
|
|
|
||
|
|
__cu_to_r = (to);
|
||
|
|
__cu_from_r = (from);
|
||
|
|
__cu_len_r = (n);
|
||
|
|
|
||
|
|
__asm__ __volatile__(
|
||
|
|
__MODULE_JAL(__raw_copy_to_user)
|
||
|
|
: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
|
||
|
|
:
|
||
|
|
: "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
|
||
|
|
DADDI_SCRATCH, "memory");
|
||
|
|
|
||
|
|
return __cu_len_r;
|
||
|
|
}
|
||
|
|
|
||
|
|
#define INLINE_COPY_FROM_USER
|
||
|
|
#define INLINE_COPY_TO_USER
|
||
|
|
|
||
|
|
extern __kernel_size_t __bzero(void __user *addr, __kernel_size_t size);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* __clear_user: - Zero a block of memory in user space, with less checking.
|
||
|
|
* @to: Destination address, in user space.
|
||
|
|
* @n: Number of bytes to zero.
|
||
|
|
*
|
||
|
|
* 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
|
||
|
|
__clear_user(void __user *addr, __kernel_size_t size)
|
||
|
|
{
|
||
|
|
__kernel_size_t res;
|
||
|
|
|
||
|
|
#ifdef CONFIG_CPU_MICROMIPS
|
||
|
|
/* micromips memset / bzero also clobbers t7 & t8 */
|
||
|
|
#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$15", "$24", "$31"
|
||
|
|
#else
|
||
|
|
#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$31"
|
||
|
|
#endif /* CONFIG_CPU_MICROMIPS */
|
||
|
|
|
||
|
|
might_fault();
|
||
|
|
__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)
|
||
|
|
: bzero_clobbers);
|
||
|
|
|
||
|
|
return res;
|
||
|
|
}
|
||
|
|
|
||
|
|
#define clear_user(addr,n) \
|
||
|
|
({ \
|
||
|
|
void __user * __cl_addr = (addr); \
|
||
|
|
unsigned long __cl_size = (n); \
|
||
|
|
if (__cl_size && access_ok(__cl_addr, __cl_size)) \
|
||
|
|
__cl_size = __clear_user(__cl_addr, __cl_size); \
|
||
|
|
__cl_size; \
|
||
|
|
})
|
||
|
|
|
||
|
|
extern long __strncpy_from_user_asm(char *__to, const char __user *__from, long __len);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* strncpy_from_user: - Copy a NUL terminated string from userspace.
|
||
|
|
* @dst: Destination address, in kernel space. This buffer must be at
|
||
|
|
* least @count bytes long.
|
||
|
|
* @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
|
||
|
|
strncpy_from_user(char *__to, const char __user *__from, long __len)
|
||
|
|
{
|
||
|
|
long res;
|
||
|
|
|
||
|
|
if (!access_ok(__from, __len))
|
||
|
|
return -EFAULT;
|
||
|
|
|
||
|
|
might_fault();
|
||
|
|
__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;
|
||
|
|
}
|
||
|
|
|
||
|
|
extern long __strnlen_user_asm(const char __user *s, long n);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* strnlen_user: - Get the size of a string in user space.
|
||
|
|
* @str: The string to measure.
|
||
|
|
*
|
||
|
|
* Context: User context only. This function may sleep if pagefaults are
|
||
|
|
* enabled.
|
||
|
|
*
|
||
|
|
* 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 the string is too long, returns a value greater than @n.
|
||
|
|
*/
|
||
|
|
static inline long strnlen_user(const char __user *s, long n)
|
||
|
|
{
|
||
|
|
long res;
|
||
|
|
|
||
|
|
if (!access_ok(s, 1))
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
might_fault();
|
||
|
|
__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;
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* _ASM_UACCESS_H */
|