baee502ce2
never initialized been initialized anywhere, just saved to and restored from signal frames so nonsense anyway. As neat side effect of being shared between all processors it was also abusable as a nice covert channel between processes. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
119 lines
2.7 KiB
C
119 lines
2.7 KiB
C
/*
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* Kevin D. Kissell, kevink@mips and Carsten Langgaard, carstenl@mips.com
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* Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
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*
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* This program is free software; you can distribute it and/or modify it
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* under the terms of the GNU General Public License (Version 2) as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
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*
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* Routines corresponding to Linux kernel FP context
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* manipulation primitives for the Algorithmics MIPS
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* FPU Emulator
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*/
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#include <linux/config.h>
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#include <linux/sched.h>
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#include <asm/processor.h>
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#include <asm/signal.h>
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#include <asm/uaccess.h>
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#include <asm/fpu_emulator.h>
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#define SIGNALLING_NAN 0x7ff800007ff80000LL
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void fpu_emulator_init_fpu(void)
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{
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static int first = 1;
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int i;
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if (first) {
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first = 0;
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printk("Algorithmics/MIPS FPU Emulator v1.5\n");
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}
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current->thread.fpu.soft.fcr31 = 0;
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for (i = 0; i < 32; i++) {
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current->thread.fpu.soft.fpr[i] = SIGNALLING_NAN;
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}
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}
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/*
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* Emulator context save/restore to/from a signal context
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* presumed to be on the user stack, and therefore accessed
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* with appropriate macros from uaccess.h
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*/
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int fpu_emulator_save_context(struct sigcontext *sc)
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{
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int i;
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int err = 0;
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for (i = 0; i < 32; i++) {
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err |=
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__put_user(current->thread.fpu.soft.fpr[i],
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&sc->sc_fpregs[i]);
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}
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err |= __put_user(current->thread.fpu.soft.fcr31, &sc->sc_fpc_csr);
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return err;
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}
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int fpu_emulator_restore_context(struct sigcontext *sc)
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{
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int i;
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int err = 0;
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for (i = 0; i < 32; i++) {
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err |=
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__get_user(current->thread.fpu.soft.fpr[i],
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&sc->sc_fpregs[i]);
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}
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err |= __get_user(current->thread.fpu.soft.fcr31, &sc->sc_fpc_csr);
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return err;
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}
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#ifdef CONFIG_64BIT
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/*
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* This is the o32 version
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*/
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int fpu_emulator_save_context32(struct sigcontext32 *sc)
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{
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int i;
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int err = 0;
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for (i = 0; i < 32; i+=2) {
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err |=
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__put_user(current->thread.fpu.soft.fpr[i],
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&sc->sc_fpregs[i]);
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}
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err |= __put_user(current->thread.fpu.soft.fcr31, &sc->sc_fpc_csr);
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return err;
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}
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int fpu_emulator_restore_context32(struct sigcontext32 *sc)
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{
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int i;
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int err = 0;
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for (i = 0; i < 32; i+=2) {
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err |=
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__get_user(current->thread.fpu.soft.fpr[i],
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&sc->sc_fpregs[i]);
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}
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err |= __get_user(current->thread.fpu.soft.fcr31, &sc->sc_fpc_csr);
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return err;
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}
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#endif
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