On Tue, Jul 15, 2014 at 10:45 AM, Ley Foon Tan <lftan@xxxxxxxxxx> wrote: > This patch adds support for signal handling. > > Signed-off-by: Ley Foon Tan <lftan@xxxxxxxxxx> > --- > arch/nios2/include/asm/signal.h | 22 +++ > arch/nios2/include/asm/ucontext.h | 34 ++++ > arch/nios2/include/uapi/asm/sigcontext.h | 30 +++ > arch/nios2/include/uapi/asm/signal.h | 23 +++ > arch/nios2/kernel/signal.c | 316 +++++++++++++++++++++++++++++++ > 5 files changed, 425 insertions(+) > create mode 100644 arch/nios2/include/asm/signal.h > create mode 100644 arch/nios2/include/asm/ucontext.h > create mode 100644 arch/nios2/include/uapi/asm/sigcontext.h > create mode 100644 arch/nios2/include/uapi/asm/signal.h > create mode 100644 arch/nios2/kernel/signal.c > > diff --git a/arch/nios2/include/asm/signal.h b/arch/nios2/include/asm/signal.h > new file mode 100644 > index 0000000..bbcf11e > --- /dev/null > +++ b/arch/nios2/include/asm/signal.h > @@ -0,0 +1,22 @@ > +/* > + * Copyright Altera Corporation (C) 2013. All rights reserved > + * > + * This program is free software; you can redistribute it and/or modify it > + * under the terms and conditions of the GNU General Public License, > + * version 2, as published by the Free Software Foundation. > + * > + * This program is distributed in the hope 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/>. > + * > + */ > +#ifndef _NIOS2_SIGNAL_H > +#define _NIOS2_SIGNAL_H > + > +#include <uapi/asm/signal.h> > + > +#endif /* _NIOS2_SIGNAL_H */ > diff --git a/arch/nios2/include/asm/ucontext.h b/arch/nios2/include/asm/ucontext.h > new file mode 100644 > index 0000000..5870ef4 > --- /dev/null > +++ b/arch/nios2/include/asm/ucontext.h > @@ -0,0 +1,34 @@ > +/* > + * Copyright (C) 2010 Tobias Klauser <tklauser@xxxxxxxxxx> > + * Copyright (C) 2004 Microtronix Datacom Ltd > + * > + * derived from m68knommu > + * > + * This file is subject to the terms and conditions of the GNU General Public > + * License. See the file "COPYING" in the main directory of this archive > + * for more details. > + */ > + > +#ifndef _ASM_NIOS2_UCONTEXT_H > +#define _ASM_NIOS2_UCONTEXT_H > + > +typedef int greg_t; > +#define NGREG 32 > +typedef greg_t gregset_t[NGREG]; > + > +struct mcontext { > + int version; > + gregset_t gregs; > +}; > + > +#define MCONTEXT_VERSION 2 > + > +struct ucontext { > + unsigned long uc_flags; > + struct ucontext *uc_link; > + stack_t uc_stack; > + struct mcontext uc_mcontext; > + sigset_t uc_sigmask; /* mask last for extensibility */ > +}; > + > +#endif > diff --git a/arch/nios2/include/uapi/asm/sigcontext.h b/arch/nios2/include/uapi/asm/sigcontext.h > new file mode 100644 > index 0000000..6bfd880 > --- /dev/null > +++ b/arch/nios2/include/uapi/asm/sigcontext.h > @@ -0,0 +1,30 @@ > +/* > + * Taken from the m68knommu. > + * > + * Copyright (C) 2004, Microtronix Datacom Ltd. > + * > + * 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 as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * 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, GOOD TITLE or > + * NON INFRINGEMENT. See the GNU General Public License for more > + * details. > + */ > + > +#ifndef _ASM_NIOS2_SIGCONTEXT_H > +#define _ASM_NIOS2_SIGCONTEXT_H > + > +#include <asm/ptrace.h> > + > +struct sigcontext { > + struct pt_regs regs; > + unsigned long sc_mask; /* old sigmask */ > +}; > + > +#endif > diff --git a/arch/nios2/include/uapi/asm/signal.h b/arch/nios2/include/uapi/asm/signal.h > new file mode 100644 > index 0000000..f29ee63 > --- /dev/null > +++ b/arch/nios2/include/uapi/asm/signal.h > @@ -0,0 +1,23 @@ > +/* > + * Copyright Altera Corporation (C) 2013. All rights reserved > + * > + * This program is free software; you can redistribute it and/or modify it > + * under the terms and conditions of the GNU General Public License, > + * version 2, as published by the Free Software Foundation. > + * > + * This program is distributed in the hope 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/>. > + * > + */ > +#ifndef _ASM_NIOS2_SIGNAL_H > +#define _ASM_NIOS2_SIGNAL_H > + > +#define SA_RESTORER 0x04000000 > +#include <asm-generic/signal.h> > + > +#endif /* _ASM_NIOS2_SIGNAL_H */ > diff --git a/arch/nios2/kernel/signal.c b/arch/nios2/kernel/signal.c > new file mode 100644 > index 0000000..3f649d8 > --- /dev/null > +++ b/arch/nios2/kernel/signal.c > @@ -0,0 +1,316 @@ > +/* > + * Copyright (C) 2013 Altera Corporation > + * Copyright (C) 2011-2012 Tobias Klauser <tklauser@xxxxxxxxxx> > + * Copyright (C) 2004 Microtronix Datacom Ltd > + * Copyright (C) 1991, 1992 Linus Torvalds > + * > + * This file is based on kernel/signal.c from m68knommu. > + * > + * This file is subject to the terms and conditions of the GNU General Public > + * License. See the file COPYING in the main directory of this archive > + * for more details. > + */ > + > +#include <linux/signal.h> > +#include <linux/errno.h> > +#include <linux/ptrace.h> > +#include <linux/uaccess.h> > +#include <linux/unistd.h> > +#include <linux/personality.h> > +#include <linux/tracehook.h> > + > +#include <asm/ucontext.h> > +#include <asm/cacheflush.h> > + > +#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) > + > +static int do_signal(struct pt_regs *regs, int in_syscall); Do you really need this prototype? > +/* > + * Do a signal return; undo the signal stack. > + * > + * Keep the return code on the stack quadword aligned! > + * That makes the cache flush below easier. > + */ > + > +struct rt_sigframe { > + struct siginfo info; > + struct ucontext uc; > +}; > + > +static inline int rt_restore_ucontext(struct pt_regs *regs, > + struct switch_stack *sw, > + struct ucontext *uc, int *pr2) > +{ > + int temp; > + greg_t *gregs = uc->uc_mcontext.gregs; > + int err; > + > + err = __get_user(temp, &uc->uc_mcontext.version); > + if (temp != MCONTEXT_VERSION) > + goto badframe; > + /* restore passed registers */ > + err |= __get_user(regs->r1, &gregs[0]); > + err |= __get_user(regs->r2, &gregs[1]); > + err |= __get_user(regs->r3, &gregs[2]); > + err |= __get_user(regs->r4, &gregs[3]); > + err |= __get_user(regs->r5, &gregs[4]); > + err |= __get_user(regs->r6, &gregs[5]); > + err |= __get_user(regs->r7, &gregs[6]); > + err |= __get_user(regs->r8, &gregs[7]); > + err |= __get_user(regs->r9, &gregs[8]); > + err |= __get_user(regs->r10, &gregs[9]); > + err |= __get_user(regs->r11, &gregs[10]); > + err |= __get_user(regs->r12, &gregs[11]); > + err |= __get_user(regs->r13, &gregs[12]); > + err |= __get_user(regs->r14, &gregs[13]); > + err |= __get_user(regs->r15, &gregs[14]); > + err |= __get_user(sw->r16, &gregs[15]); > + err |= __get_user(sw->r17, &gregs[16]); > + err |= __get_user(sw->r18, &gregs[17]); > + err |= __get_user(sw->r19, &gregs[18]); > + err |= __get_user(sw->r20, &gregs[19]); > + err |= __get_user(sw->r21, &gregs[20]); > + err |= __get_user(sw->r22, &gregs[21]); > + err |= __get_user(sw->r23, &gregs[22]); > + /* gregs[23] is handled below */ > + err |= __get_user(sw->fp, &gregs[24]); /* Verify, should this be > + settable */ > + err |= __get_user(sw->gp, &gregs[25]); /* Verify, should this be > + settable */ > + > + err |= __get_user(temp, &gregs[26]); /* Not really necessary no user > + settable bits */ > + err |= __get_user(regs->ea, &gregs[27]); > + > + err |= __get_user(regs->ra, &gregs[23]); > + err |= __get_user(regs->sp, &gregs[28]); > + > + regs->estatus = (regs->estatus & 0xffffffff); > + regs->orig_r2 = -1; /* disable syscall checks */ > + > + err |= restore_altstack(&uc->uc_stack); > + if (err) > + goto badframe; > + > + *pr2 = regs->r2; > + return err; > + > +badframe: > + return 1; > +} > + > +asmlinkage int do_rt_sigreturn(struct switch_stack *sw) > +{ > + struct pt_regs *regs = (struct pt_regs *)(sw + 1); > + /* Verify, can we follow the stack back */ > + struct rt_sigframe *frame = (struct rt_sigframe *) regs->sp; > + sigset_t set; > + int rval; > + > + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) > + goto badframe; > + > + if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) > + goto badframe; > + > + sigdelsetmask(&set, ~_BLOCKABLE); > + spin_lock_irq(¤t->sighand->siglock); > + current->blocked = set; > + recalc_sigpending(); > + spin_unlock_irq(¤t->sighand->siglock); Why aren't you using set_current_blocked() here? > + if (rt_restore_ucontext(regs, sw, &frame->uc, &rval)) > + goto badframe; > + > + return rval; > + > +badframe: > + force_sig(SIGSEGV, current); > + return 0; > +} > + > +static inline int rt_setup_ucontext(struct ucontext *uc, struct pt_regs *regs) > +{ > + struct switch_stack *sw = (struct switch_stack *)regs - 1; > + greg_t *gregs = uc->uc_mcontext.gregs; > + int err = 0; > + > + err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); > + err |= __put_user(regs->r1, &gregs[0]); > + err |= __put_user(regs->r2, &gregs[1]); > + err |= __put_user(regs->r3, &gregs[2]); > + err |= __put_user(regs->r4, &gregs[3]); > + err |= __put_user(regs->r5, &gregs[4]); > + err |= __put_user(regs->r6, &gregs[5]); > + err |= __put_user(regs->r7, &gregs[6]); > + err |= __put_user(regs->r8, &gregs[7]); > + err |= __put_user(regs->r9, &gregs[8]); > + err |= __put_user(regs->r10, &gregs[9]); > + err |= __put_user(regs->r11, &gregs[10]); > + err |= __put_user(regs->r12, &gregs[11]); > + err |= __put_user(regs->r13, &gregs[12]); > + err |= __put_user(regs->r14, &gregs[13]); > + err |= __put_user(regs->r15, &gregs[14]); > + err |= __put_user(sw->r16, &gregs[15]); > + err |= __put_user(sw->r17, &gregs[16]); > + err |= __put_user(sw->r18, &gregs[17]); > + err |= __put_user(sw->r19, &gregs[18]); > + err |= __put_user(sw->r20, &gregs[19]); > + err |= __put_user(sw->r21, &gregs[20]); > + err |= __put_user(sw->r22, &gregs[21]); > + err |= __put_user(sw->r23, &gregs[22]); > + err |= __put_user(regs->ra, &gregs[23]); > + err |= __put_user(sw->fp, &gregs[24]); > + err |= __put_user(sw->gp, &gregs[25]); > + err |= __put_user(regs->ea, &gregs[27]); > + err |= __put_user(regs->sp, &gregs[28]); > + return err; > +} > + > +static inline void push_cache(unsigned long vaddr) > +{ > + flush_dcache_range(vaddr, vaddr + 12); > + flush_icache_range(vaddr, vaddr + 12); > +} > + > +static inline void *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, > + size_t frame_size) > +{ > + unsigned long usp; > + > + /* Default to using normal stack. */ > + usp = regs->sp; > + > + /* This is the X/Open sanctioned signal stack switching. */ > + usp = sigsp(usp, ksig); > + > + /* Verify, is it 32 or 64 bit aligned */ > + return (void *)((usp - frame_size) & -8UL); > +} > + > +static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, > + struct pt_regs *regs) > +{ > + struct rt_sigframe *frame; > + int err = 0; > + > + frame = get_sigframe(ksig, regs, sizeof(*frame)); > + > + if (ksig->ka.sa.sa_flags & SA_SIGINFO) > + err |= copy_siginfo_to_user(&frame->info, &ksig->info); > + > + /* Create the ucontext. */ > + err |= __put_user(0, &frame->uc.uc_flags); > + err |= __put_user(0, &frame->uc.uc_link); > + err |= __save_altstack(&frame->uc.uc_stack, regs->sp); > + err |= rt_setup_ucontext(&frame->uc, regs); > + err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); You neither check nor propagate this error code. > + /* Set up to return from userspace; jump to fixed address sigreturn > + trampoline on kuser page. */ > + regs->ra = (unsigned long) (0x1040); > + > + /* Set up registers for signal handler */ > + regs->sp = (unsigned long) frame; > + regs->r4 = (unsigned long) ksig->sig; > + regs->r5 = (unsigned long) &frame->info; > + regs->r6 = (unsigned long) &frame->uc; > + regs->ea = (unsigned long) ksig->ka.sa.sa_handler; > + return 0; > +} > + > +static inline void handle_restart(struct pt_regs *regs, struct k_sigaction *ka, > + int has_handler) > +{ > + switch (regs->r2) { > + case ERESTART_RESTARTBLOCK: > + case ERESTARTNOHAND: > + regs->r2 = EINTR; > + regs->r7 = 1; > + break; > + case ERESTARTSYS: > + if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) { > + regs->r2 = EINTR; > + regs->r7 = 1; > + break; > + } > + /* fallthrough */ > + case ERESTARTNOINTR: > + regs->r2 = regs->orig_r2; > + regs->r7 = regs->orig_r7; > + regs->ea -= 4; > + break; > + } > +} > + > +/* > + * OK, we're invoking a handler > + */ > +static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) > +{ > + int ret; > + sigset_t *oldset = sigmask_to_save(); > + > + /* set up the stack frame */ > + ret = setup_rt_frame(ksig, oldset, regs); > + > + signal_setup_done(ret, ksig, 0); > +} > + > +static int do_signal(struct pt_regs *regs, int in_syscall) > +{ > + struct ksignal ksig; > + > + current->thread.kregs = regs; > + > + if (get_signal(&ksig)) { > + /* > + * Are we from a system call? If so, check system call > + * restarting. > + */ > + if (in_syscall) > + handle_restart(regs, &ksig.ka, 1); > + /* Whee! Actually deliver the signal. */ > + handle_signal(&ksig, regs); > + return 1; > + } > + > + /* > + * No signal to deliver to the process - restart the syscall. > + */ > + if (in_syscall) { > + /* Did the syscall return an error code */ > + if (regs->r7 == 1) { > + if (regs->r2 == ERESTARTNOHAND || > + regs->r2 == ERESTARTSYS || > + regs->r2 == ERESTARTNOINTR) { > + regs->r2 = regs->orig_r2; > + regs->r7 = regs->orig_r7; > + regs->ea -= 4; > + } else if (regs->r2 == ERESTART_RESTARTBLOCK) { > + regs->r2 = __NR_restart_syscall; > + regs->ea -= 4; > + } > + } > + } > + > + return 0; > +} > + > +asmlinkage void do_notify_resume(struct pt_regs *regs, int in_syscall) > +{ > + /* > + * We want the common case to go fast, which is why we may in certain > + * cases get here from kernel mode. Just return without doing anything > + * if so. > + */ > + if (!user_mode(regs)) > + return; > + > + if (test_thread_flag(TIF_SIGPENDING)) > + do_signal(regs, in_syscall); > + > + if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) > + tracehook_notify_resume(regs); > +} > -- > 1.8.2.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-arch" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Thanks, //richard -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
