80 строки
1.5 KiB
ArmAsm
80 строки
1.5 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* User memory copying routines for the Hexagon Kernel
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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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/* The right way to do this involves valignb
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* The easy way to do this is only speed up src/dest similar alignment.
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*/
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/*
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* Copy to/from user are the same, except that for packets with a load and
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* a store, I don't know how to tell which kind of exception we got.
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* Therefore, we duplicate the function, and handle faulting addresses
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* differently for each function
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*/
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/*
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* copy to user: stores can fault
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*/
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#define src_sav r13
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#define dst_sav r12
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#define src_dst_sav r13:12
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#define d_dbuf r15:14
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#define w_dbuf r15
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#define dst r0
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#define src r1
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#define bytes r2
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#define loopcount r5
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#define FUNCNAME raw_copy_to_user
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#include "copy_user_template.S"
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/* STORE FAULTS from COPY_TO_USER */
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.falign
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1109:
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2109:
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4109:
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/* Alignment loop. r2 has been updated. Return it. */
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{
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r0 = r2
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jumpr r31
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}
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/* Normal copy loops. Use dst-dst_sav to compute distance */
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/* dst holds best write, no need to unwind any loops */
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/* X - (A - B) == X + B - A */
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.falign
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8189:
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8199:
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4189:
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4199:
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2189:
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2199:
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1189:
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1199:
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{
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r2 += sub(dst_sav,dst)
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}
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{
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r0 = r2
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jumpr r31
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}
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/* COPY TO USER: only stores can fail */
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.section __ex_table,"a"
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.long 1100b,1109b
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.long 2100b,2109b
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.long 4100b,4109b
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.long 8180b,8189b
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.long 8190b,8199b
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.long 4180b,4189b
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.long 4190b,4199b
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.long 2180b,2189b
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.long 2190b,2199b
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.long 1180b,1189b
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.long 1190b,1199b
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.previous
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