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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 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 see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
83 lines
1.7 KiB
C
83 lines
1.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (C) 2013 ARM Ltd.
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*/
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#ifndef __ASM_WORD_AT_A_TIME_H
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#define __ASM_WORD_AT_A_TIME_H
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#include <linux/uaccess.h>
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#ifndef __AARCH64EB__
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#include <linux/kernel.h>
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struct word_at_a_time {
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const unsigned long one_bits, high_bits;
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};
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#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }
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static inline unsigned long has_zero(unsigned long a, unsigned long *bits,
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const struct word_at_a_time *c)
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{
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unsigned long mask = ((a - c->one_bits) & ~a) & c->high_bits;
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*bits = mask;
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return mask;
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}
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#define prep_zero_mask(a, bits, c) (bits)
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static inline unsigned long create_zero_mask(unsigned long bits)
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{
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bits = (bits - 1) & ~bits;
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return bits >> 7;
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}
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static inline unsigned long find_zero(unsigned long mask)
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{
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return fls64(mask) >> 3;
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}
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#define zero_bytemask(mask) (mask)
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#else /* __AARCH64EB__ */
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#include <asm-generic/word-at-a-time.h>
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#endif
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/*
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* Load an unaligned word from kernel space.
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*
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* In the (very unlikely) case of the word being a page-crosser
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* and the next page not being mapped, take the exception and
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* return zeroes in the non-existing part.
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*/
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static inline unsigned long load_unaligned_zeropad(const void *addr)
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{
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unsigned long ret, offset;
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/* Load word from unaligned pointer addr */
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asm(
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"1: ldr %0, %3\n"
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"2:\n"
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" .pushsection .fixup,\"ax\"\n"
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" .align 2\n"
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"3: and %1, %2, #0x7\n"
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" bic %2, %2, #0x7\n"
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" ldr %0, [%2]\n"
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" lsl %1, %1, #0x3\n"
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#ifndef __AARCH64EB__
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" lsr %0, %0, %1\n"
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#else
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" lsl %0, %0, %1\n"
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#endif
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" b 2b\n"
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" .popsection\n"
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_ASM_EXTABLE(1b, 3b)
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: "=&r" (ret), "=&r" (offset)
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: "r" (addr), "Q" (*(unsigned long *)addr));
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return ret;
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}
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#endif /* __ASM_WORD_AT_A_TIME_H */
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