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e50be648aa
It is safer and simpler to drop the uaccess assembly macros in favour of
inline C functions. Although this bloats the Image size slightly, it
aligns our user copy routines with '{get,put}_user()' and generally
makes the code a lot easier to reason about.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
[will: tweaked commit message and changed temporary variable names]
Signed-off-by: Will Deacon <will@kernel.org>
69 lines
1.3 KiB
ArmAsm
69 lines
1.3 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (C) 2012 ARM Ltd.
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*/
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#include <linux/linkage.h>
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#include <asm/asm-uaccess.h>
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#include <asm/assembler.h>
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#include <asm/cache.h>
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/*
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* Copy from user space to a kernel buffer (alignment handled by the hardware)
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*
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* Parameters:
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* x0 - to
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* x1 - from
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* x2 - n
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* Returns:
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* x0 - bytes not copied
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*/
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.macro ldrb1 ptr, regB, val
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uao_user_alternative 9998f, ldrb, ldtrb, \ptr, \regB, \val
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.endm
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.macro strb1 ptr, regB, val
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strb \ptr, [\regB], \val
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.endm
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.macro ldrh1 ptr, regB, val
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uao_user_alternative 9998f, ldrh, ldtrh, \ptr, \regB, \val
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.endm
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.macro strh1 ptr, regB, val
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strh \ptr, [\regB], \val
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.endm
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.macro ldr1 ptr, regB, val
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uao_user_alternative 9998f, ldr, ldtr, \ptr, \regB, \val
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.endm
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.macro str1 ptr, regB, val
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str \ptr, [\regB], \val
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.endm
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.macro ldp1 ptr, regB, regC, val
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uao_ldp 9998f, \ptr, \regB, \regC, \val
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.endm
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.macro stp1 ptr, regB, regC, val
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stp \ptr, \regB, [\regC], \val
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.endm
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end .req x5
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ENTRY(__arch_copy_from_user)
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add end, x0, x2
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#include "copy_template.S"
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mov x0, #0 // Nothing to copy
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ret
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ENDPROC(__arch_copy_from_user)
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EXPORT_SYMBOL(__arch_copy_from_user)
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.section .fixup,"ax"
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.align 2
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9998: sub x0, end, dst // bytes not copied
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ret
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.previous
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