Hexagon: Add signal functions
Signed-off-by: Richard Kuo <rkuo@codeaurora.org> Signed-off-by: Linas Vepstas <linas@codeaurora.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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33
arch/hexagon/include/asm/sigcontext.h
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33
arch/hexagon/include/asm/sigcontext.h
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/*
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* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 and
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* only version 2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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* 02110-1301, USA.
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*/
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#ifndef _ASM_SIGCONTEXT_H
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#define _ASM_SIGCONTEXT_H
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#include <asm/user.h>
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/*
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* Signal context structure - contains all info to do with the state
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* before the signal handler was invoked. Note: only add new entries
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* to the end of the structure.
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*/
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struct sigcontext {
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struct user_regs_struct sc_regs;
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} __aligned(8);
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#endif
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26
arch/hexagon/include/asm/signal.h
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26
arch/hexagon/include/asm/signal.h
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/*
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* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 and
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* only version 2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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* 02110-1301, USA.
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*/
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#ifndef _ASM_SIGNAL_H
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#define _ASM_SIGNAL_H
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extern unsigned long __rt_sigtramp_template[2];
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#include <asm-generic/signal.h>
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#endif
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30
arch/hexagon/include/asm/vdso.h
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30
arch/hexagon/include/asm/vdso.h
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@ -0,0 +1,30 @@
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/*
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* vDSO implementation for Hexagon
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*
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* Copyright (c) 2011, Code Aurora Forum. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 and
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* only version 2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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* 02110-1301, USA.
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*/
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#ifndef __ASM_VDSO_H
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#define __ASM_VDSO_H
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#include <linux/types.h>
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struct hexagon_vdso {
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u32 rt_signal_trampoline[2];
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};
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#endif /* __ASM_VDSO_H */
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345
arch/hexagon/kernel/signal.c
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345
arch/hexagon/kernel/signal.c
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/*
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* Signal support for Hexagon processor
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*
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* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 and
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* only version 2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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* 02110-1301, USA.
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*/
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#include <linux/linkage.h>
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#include <linux/syscalls.h>
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#include <linux/freezer.h>
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#include <linux/tracehook.h>
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#include <asm/registers.h>
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#include <asm/thread_info.h>
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#include <asm/unistd.h>
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#include <asm/uaccess.h>
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#include <asm/ucontext.h>
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#include <asm/cacheflush.h>
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#include <asm/signal.h>
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#include <asm/vdso.h>
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#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
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struct rt_sigframe {
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unsigned long tramp[2];
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struct siginfo info;
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struct ucontext uc;
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};
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static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
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size_t frame_size)
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{
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unsigned long sp = regs->r29;
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/* Switch to signal stack if appropriate */
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if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags(sp) == 0))
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sp = current->sas_ss_sp + current->sas_ss_size;
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return (void __user *)((sp - frame_size) & ~(sizeof(long long) - 1));
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}
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static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
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{
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unsigned long tmp;
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int err = 0;
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err |= copy_to_user(&sc->sc_regs.r0, ®s->r00,
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32*sizeof(unsigned long));
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err |= __put_user(regs->sa0, &sc->sc_regs.sa0);
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err |= __put_user(regs->lc0, &sc->sc_regs.lc0);
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err |= __put_user(regs->sa1, &sc->sc_regs.sa1);
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err |= __put_user(regs->lc1, &sc->sc_regs.lc1);
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err |= __put_user(regs->m0, &sc->sc_regs.m0);
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err |= __put_user(regs->m1, &sc->sc_regs.m1);
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err |= __put_user(regs->usr, &sc->sc_regs.usr);
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err |= __put_user(regs->preds, &sc->sc_regs.p3_0);
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err |= __put_user(regs->gp, &sc->sc_regs.gp);
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err |= __put_user(regs->ugp, &sc->sc_regs.ugp);
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tmp = pt_elr(regs); err |= __put_user(tmp, &sc->sc_regs.pc);
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tmp = pt_cause(regs); err |= __put_user(tmp, &sc->sc_regs.cause);
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tmp = pt_badva(regs); err |= __put_user(tmp, &sc->sc_regs.badva);
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return err;
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}
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static int restore_sigcontext(struct pt_regs *regs,
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struct sigcontext __user *sc)
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{
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unsigned long tmp;
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int err = 0;
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err |= copy_from_user(®s->r00, &sc->sc_regs.r0,
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32 * sizeof(unsigned long));
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err |= __get_user(regs->sa0, &sc->sc_regs.sa0);
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err |= __get_user(regs->lc0, &sc->sc_regs.lc0);
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err |= __get_user(regs->sa1, &sc->sc_regs.sa1);
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err |= __get_user(regs->lc1, &sc->sc_regs.lc1);
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err |= __get_user(regs->m0, &sc->sc_regs.m0);
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err |= __get_user(regs->m1, &sc->sc_regs.m1);
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err |= __get_user(regs->usr, &sc->sc_regs.usr);
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err |= __get_user(regs->preds, &sc->sc_regs.p3_0);
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err |= __get_user(regs->gp, &sc->sc_regs.gp);
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err |= __get_user(regs->ugp, &sc->sc_regs.ugp);
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err |= __get_user(tmp, &sc->sc_regs.pc); pt_set_elr(regs, tmp);
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return err;
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}
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/*
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* Setup signal stack frame with siginfo structure
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*/
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static int setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info,
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sigset_t *set, struct pt_regs *regs)
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{
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int err = 0;
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struct rt_sigframe __user *frame;
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struct hexagon_vdso *vdso = current->mm->context.vdso;
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frame = get_sigframe(ka, regs, sizeof(struct rt_sigframe));
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if (!access_ok(VERIFY_WRITE, frame, sizeof(struct rt_sigframe)))
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goto sigsegv;
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if (copy_siginfo_to_user(&frame->info, info))
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goto sigsegv;
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/* The on-stack signal trampoline is no longer executed;
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* however, the libgcc signal frame unwinding code checks for
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* the presence of these two numeric magic values.
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*/
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err |= __put_user(0x7800d166, &frame->tramp[0]);
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err |= __put_user(0x5400c004, &frame->tramp[1]);
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err |= setup_sigcontext(regs, &frame->uc.uc_mcontext);
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err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
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if (err)
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goto sigsegv;
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/* Load r0/r1 pair with signumber/siginfo pointer... */
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regs->r0100 = ((unsigned long long)((unsigned long)&frame->info) << 32)
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| (unsigned long long)signr;
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regs->r02 = (unsigned long) &frame->uc;
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regs->r31 = (unsigned long) vdso->rt_signal_trampoline;
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pt_psp(regs) = (unsigned long) frame;
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pt_set_elr(regs, (unsigned long)ka->sa.sa_handler);
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return 0;
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sigsegv:
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force_sigsegv(signr, current);
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return -EFAULT;
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}
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/*
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* Setup invocation of signal handler
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*/
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static int handle_signal(int sig, siginfo_t *info, struct k_sigaction *ka,
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sigset_t *oldset, struct pt_regs *regs)
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{
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int rc;
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/*
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* If we're handling a signal that aborted a system call,
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* set up the error return value before adding the signal
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* frame to the stack.
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*/
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if (regs->syscall_nr >= 0) {
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switch (regs->r00) {
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case -ERESTART_RESTARTBLOCK:
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case -ERESTARTNOHAND:
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regs->r00 = -EINTR;
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break;
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case -ERESTARTSYS:
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if (!(ka->sa.sa_flags & SA_RESTART)) {
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regs->r00 = -EINTR;
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break;
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}
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/* Fall through */
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case -ERESTARTNOINTR:
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regs->r06 = regs->syscall_nr;
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pt_set_elr(regs, pt_elr(regs) - 4);
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regs->r00 = regs->restart_r0;
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break;
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default:
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break;
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}
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}
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/*
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* Set up the stack frame; not doing the SA_SIGINFO thing. We
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* only set up the rt_frame flavor.
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*/
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rc = setup_rt_frame(sig, ka, info, oldset, regs);
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/* If there was an error on setup, no signal was delivered. */
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if (rc)
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return rc;
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spin_lock_irq(¤t->sighand->siglock);
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sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask);
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if (!(ka->sa.sa_flags & SA_NODEFER))
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sigaddset(¤t->blocked, sig);
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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return 0;
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}
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/*
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* Called from return-from-event code.
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*/
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static void do_signal(struct pt_regs *regs)
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{
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struct k_sigaction sigact;
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siginfo_t info;
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int signo;
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if (!user_mode(regs))
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return;
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if (try_to_freeze())
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goto no_signal;
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signo = get_signal_to_deliver(&info, &sigact, regs, NULL);
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if (signo > 0) {
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sigset_t *oldset;
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if (test_thread_flag(TIF_RESTORE_SIGMASK))
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oldset = ¤t->saved_sigmask;
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else
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oldset = ¤t->blocked;
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if (handle_signal(signo, &info, &sigact, oldset, regs) == 0) {
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/*
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* Successful delivery case. The saved sigmask is
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* stored in the signal frame, and will be restored
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* by sigreturn. We can clear the TIF flag.
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*/
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clear_thread_flag(TIF_RESTORE_SIGMASK);
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tracehook_signal_handler(signo, &info, &sigact, regs,
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test_thread_flag(TIF_SINGLESTEP));
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}
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return;
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}
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no_signal:
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/*
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* If we came from a system call, handle the restart.
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*/
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if (regs->syscall_nr >= 0) {
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switch (regs->r00) {
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case -ERESTARTNOHAND:
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case -ERESTARTSYS:
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case -ERESTARTNOINTR:
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regs->r06 = regs->syscall_nr;
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break;
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case -ERESTART_RESTARTBLOCK:
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regs->r06 = __NR_restart_syscall;
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break;
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default:
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goto no_restart;
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}
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pt_set_elr(regs, pt_elr(regs) - 4);
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regs->r00 = regs->restart_r0;
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}
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no_restart:
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/* If there's no signal to deliver, put the saved sigmask back */
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if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
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clear_thread_flag(TIF_RESTORE_SIGMASK);
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sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
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}
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}
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void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags)
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{
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if (thread_info_flags & _TIF_SIGPENDING)
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do_signal(regs);
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if (thread_info_flags & _TIF_NOTIFY_RESUME) {
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clear_thread_flag(TIF_NOTIFY_RESUME);
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if (current->replacement_session_keyring)
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key_replace_session_keyring();
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}
|
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}
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/*
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* Architecture-specific wrappers for signal-related system calls
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*/
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asmlinkage int sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
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{
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struct pt_regs *regs = current_thread_info()->regs;
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return do_sigaltstack(uss, uoss, regs->r29);
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}
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asmlinkage int sys_rt_sigreturn(void)
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{
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struct pt_regs *regs = current_thread_info()->regs;
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struct rt_sigframe __user *frame;
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sigset_t blocked;
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frame = (struct rt_sigframe __user *)pt_psp(regs);
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if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
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goto badframe;
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if (__copy_from_user(&blocked, &frame->uc.uc_sigmask, sizeof(blocked)))
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goto badframe;
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|
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sigdelsetmask(&blocked, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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current->blocked = blocked;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
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goto badframe;
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|
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/* Restore the user's stack as well */
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pt_psp(regs) = regs->r29;
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|
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/*
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* Leave a trace in the stack frame that this was a sigreturn.
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* If the system call is to replay, we've already restored the
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* number in the GPR slot and it will be regenerated on the
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* new system call trap entry. Note that if restore_sigcontext()
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* did something other than a bulk copy of the pt_regs struct,
|
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* we could avoid this assignment by simply not overwriting
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* regs->syscall_nr.
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*/
|
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regs->syscall_nr = __NR_rt_sigreturn;
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|
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/*
|
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* If we were meticulous, we'd only call this if we knew that
|
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* we were actually going to use an alternate stack, and we'd
|
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* consider any error to be fatal. What we do here, in common
|
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* with many other architectures, is call it blindly and only
|
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* consider the -EFAULT return case to be proof of a problem.
|
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*/
|
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if (do_sigaltstack(&frame->uc.uc_stack, NULL, pt_psp(regs)) == -EFAULT)
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goto badframe;
|
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|
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return 0;
|
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|
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badframe:
|
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force_sig(SIGSEGV, current);
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return 0;
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}
|
35
arch/hexagon/kernel/trampoline.S
Normal file
35
arch/hexagon/kernel/trampoline.S
Normal file
|
@ -0,0 +1,35 @@
|
|||
/*
|
||||
* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
|
||||
*
|
||||
* 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.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Trampoline sequences to be copied onto user stack.
|
||||
* This consumes a little more space than hand-assembling
|
||||
* immediate constants for use in C, but is more portable
|
||||
* to future tweaks to the Hexagon instruction set.
|
||||
*/
|
||||
|
||||
#include <asm/unistd.h>
|
||||
|
||||
/* Sig trampolines - call sys_sigreturn or sys_rt_sigreturn as appropriate */
|
||||
|
||||
/* plain sigreturn is gone. */
|
||||
|
||||
.globl __rt_sigtramp_template
|
||||
__rt_sigtramp_template:
|
||||
r6 = #__NR_rt_sigreturn;
|
||||
trap0(#1);
|
100
arch/hexagon/kernel/vdso.c
Normal file
100
arch/hexagon/kernel/vdso.c
Normal file
|
@ -0,0 +1,100 @@
|
|||
/*
|
||||
* vDSO implementation for Hexagon
|
||||
*
|
||||
* Copyright (c) 2011, Code Aurora Forum. All rights reserved.
|
||||
*
|
||||
* 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.
|
||||
*/
|
||||
|
||||
#include <linux/err.h>
|
||||
#include <linux/mm.h>
|
||||
#include <linux/vmalloc.h>
|
||||
|
||||
#include <asm/vdso.h>
|
||||
|
||||
static struct page *vdso_page;
|
||||
|
||||
/* Create a vDSO page holding the signal trampoline.
|
||||
* We want this for a non-executable stack.
|
||||
*/
|
||||
static int __init vdso_init(void)
|
||||
{
|
||||
struct hexagon_vdso *vdso;
|
||||
|
||||
vdso_page = alloc_page(GFP_KERNEL);
|
||||
if (!vdso_page)
|
||||
panic("Cannot allocate vdso");
|
||||
|
||||
vdso = vmap(&vdso_page, 1, 0, PAGE_KERNEL);
|
||||
if (!vdso)
|
||||
panic("Cannot map vdso");
|
||||
clear_page(vdso);
|
||||
|
||||
/* Install the signal trampoline; currently looks like this:
|
||||
* r6 = #__NR_rt_sigreturn;
|
||||
* trap0(#1);
|
||||
*/
|
||||
vdso->rt_signal_trampoline[0] = __rt_sigtramp_template[0];
|
||||
vdso->rt_signal_trampoline[1] = __rt_sigtramp_template[1];
|
||||
|
||||
vunmap(vdso);
|
||||
|
||||
return 0;
|
||||
}
|
||||
arch_initcall(vdso_init);
|
||||
|
||||
/*
|
||||
* Called from binfmt_elf. Create a VMA for the vDSO page.
|
||||
*/
|
||||
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
|
||||
{
|
||||
int ret;
|
||||
unsigned long vdso_base;
|
||||
struct mm_struct *mm = current->mm;
|
||||
|
||||
down_write(&mm->mmap_sem);
|
||||
|
||||
/* Try to get it loaded right near ld.so/glibc. */
|
||||
vdso_base = STACK_TOP;
|
||||
|
||||
vdso_base = get_unmapped_area(NULL, vdso_base, PAGE_SIZE, 0, 0);
|
||||
if (IS_ERR_VALUE(vdso_base)) {
|
||||
ret = vdso_base;
|
||||
goto up_fail;
|
||||
}
|
||||
|
||||
/* MAYWRITE to allow gdb to COW and set breakpoints. */
|
||||
ret = install_special_mapping(mm, vdso_base, PAGE_SIZE,
|
||||
VM_READ|VM_EXEC|
|
||||
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
|
||||
VM_ALWAYSDUMP,
|
||||
&vdso_page);
|
||||
|
||||
if (ret)
|
||||
goto up_fail;
|
||||
|
||||
mm->context.vdso = (void *)vdso_base;
|
||||
|
||||
up_fail:
|
||||
up_write(&mm->mmap_sem);
|
||||
return ret;
|
||||
}
|
||||
|
||||
const char *arch_vma_name(struct vm_area_struct *vma)
|
||||
{
|
||||
if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
|
||||
return "[vdso]";
|
||||
return NULL;
|
||||
}
|
Loading…
Reference in a new issue