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08dbd0f8ef
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 and only version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 94 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141334.043630402@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
45 lines
1.1 KiB
C
45 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
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*/
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/*
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* Support for user memory access from kernel. This will
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* probably be inlined for performance at some point, but
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* for ease of debug, and to a lesser degree for code size,
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* we implement here as subroutines.
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*/
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#include <linux/types.h>
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#include <linux/uaccess.h>
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#include <asm/pgtable.h>
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/*
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* For clear_user(), exploit previously defined copy_to_user function
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* and the fact that we've got a handy zero page defined in kernel/head.S
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*
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* dczero here would be even faster.
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*/
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__kernel_size_t __clear_user_hexagon(void __user *dest, unsigned long count)
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{
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long uncleared;
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while (count > PAGE_SIZE) {
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uncleared = raw_copy_to_user(dest, &empty_zero_page, PAGE_SIZE);
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if (uncleared)
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return count - (PAGE_SIZE - uncleared);
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count -= PAGE_SIZE;
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dest += PAGE_SIZE;
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}
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if (count)
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count = raw_copy_to_user(dest, &empty_zero_page, count);
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return count;
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}
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unsigned long clear_user_hexagon(void __user *dest, unsigned long count)
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{
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if (!access_ok(dest, count))
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return count;
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else
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return __clear_user_hexagon(dest, count);
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}
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