From: Greentime Hu <greent...@andestech.com> This patch adds support for signal handling.
Signed-off-by: Vincent Chen <vince...@andestech.com> Signed-off-by: Greentime Hu <greent...@andestech.com> --- arch/nds32/include/uapi/asm/sigcontext.h | 73 +++++++ arch/nds32/kernel/signal.c | 350 ++++++++++++++++++++++++++++++ 2 files changed, 423 insertions(+) create mode 100644 arch/nds32/include/uapi/asm/sigcontext.h create mode 100644 arch/nds32/kernel/signal.c diff --git a/arch/nds32/include/uapi/asm/sigcontext.h b/arch/nds32/include/uapi/asm/sigcontext.h new file mode 100644 index 0000000..1c0dfcb --- /dev/null +++ b/arch/nds32/include/uapi/asm/sigcontext.h @@ -0,0 +1,73 @@ +/* + * Copyright (C) 2005-2017 Andes Technology Corporation + * + * 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/>. + */ + +#ifndef _ASMNDS32_SIGCONTEXT_H +#define _ASMNDS32_SIGCONTEXT_H + +/* + * Signal context structure - contains all info to do with the state + * before the signal handler was invoked. Note: only add new entries + * to the end of the structure. + */ + +struct zol_struct { + unsigned long nds32_lc; /* $LC */ + unsigned long nds32_le; /* $LE */ + unsigned long nds32_lb; /* $LB */ +}; + +struct sigcontext { + unsigned long trap_no; + unsigned long error_code; + unsigned long oldmask; + unsigned long nds32_r0; + unsigned long nds32_r1; + unsigned long nds32_r2; + unsigned long nds32_r3; + unsigned long nds32_r4; + unsigned long nds32_r5; + unsigned long nds32_r6; + unsigned long nds32_r7; + unsigned long nds32_r8; + unsigned long nds32_r9; + unsigned long nds32_r10; + unsigned long nds32_r11; + unsigned long nds32_r12; + unsigned long nds32_r13; + unsigned long nds32_r14; + unsigned long nds32_r15; + unsigned long nds32_r16; + unsigned long nds32_r17; + unsigned long nds32_r18; + unsigned long nds32_r19; + unsigned long nds32_r20; + unsigned long nds32_r21; + unsigned long nds32_r22; + unsigned long nds32_r23; + unsigned long nds32_r24; + unsigned long nds32_r25; + unsigned long nds32_fp; /* $r28 */ + unsigned long nds32_gp; /* $r29 */ + unsigned long nds32_lp; /* $r30 */ + unsigned long nds32_sp; /* $r31 */ + unsigned long nds32_ipc; + unsigned long fault_address; + unsigned long used_math_flag; + /* FPU Registers */ + struct zol_struct zol; +}; + +#endif diff --git a/arch/nds32/kernel/signal.c b/arch/nds32/kernel/signal.c new file mode 100644 index 0000000..f43248a --- /dev/null +++ b/arch/nds32/kernel/signal.c @@ -0,0 +1,350 @@ +/* + * Copyright (C) 2005-2017 Andes Technology Corporation + * + * 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/>. + */ + +#include <linux/errno.h> +#include <linux/signal.h> +#include <linux/ptrace.h> +#include <linux/personality.h> +#include <linux/freezer.h> +#include <linux/tracehook.h> +#include <linux/uaccess.h> + +#include <asm/cacheflush.h> +#include <asm/ucontext.h> +#include <asm/unistd.h> + +#include <asm/ptrace.h> +#include <asm/vdso.h> + +struct rt_sigframe { + struct siginfo info; + struct ucontext uc; +}; + +static int restore_sigframe(struct pt_regs *regs, + struct rt_sigframe __user * sf) +{ + sigset_t set; + int err; + + err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set)); + if (err == 0) { + set_current_blocked(&set); + } + + __get_user_error(regs->uregs[0], &sf->uc.uc_mcontext.nds32_r0, err); + __get_user_error(regs->uregs[1], &sf->uc.uc_mcontext.nds32_r1, err); + __get_user_error(regs->uregs[2], &sf->uc.uc_mcontext.nds32_r2, err); + __get_user_error(regs->uregs[3], &sf->uc.uc_mcontext.nds32_r3, err); + __get_user_error(regs->uregs[4], &sf->uc.uc_mcontext.nds32_r4, err); + __get_user_error(regs->uregs[5], &sf->uc.uc_mcontext.nds32_r5, err); + __get_user_error(regs->uregs[6], &sf->uc.uc_mcontext.nds32_r6, err); + __get_user_error(regs->uregs[7], &sf->uc.uc_mcontext.nds32_r7, err); + __get_user_error(regs->uregs[8], &sf->uc.uc_mcontext.nds32_r8, err); + __get_user_error(regs->uregs[9], &sf->uc.uc_mcontext.nds32_r9, err); + __get_user_error(regs->uregs[10], &sf->uc.uc_mcontext.nds32_r10, err); + __get_user_error(regs->uregs[11], &sf->uc.uc_mcontext.nds32_r11, err); + __get_user_error(regs->uregs[12], &sf->uc.uc_mcontext.nds32_r12, err); + __get_user_error(regs->uregs[13], &sf->uc.uc_mcontext.nds32_r13, err); + __get_user_error(regs->uregs[14], &sf->uc.uc_mcontext.nds32_r14, err); + __get_user_error(regs->uregs[15], &sf->uc.uc_mcontext.nds32_r15, err); + __get_user_error(regs->uregs[16], &sf->uc.uc_mcontext.nds32_r16, err); + __get_user_error(regs->uregs[17], &sf->uc.uc_mcontext.nds32_r17, err); + __get_user_error(regs->uregs[18], &sf->uc.uc_mcontext.nds32_r18, err); + __get_user_error(regs->uregs[19], &sf->uc.uc_mcontext.nds32_r19, err); + __get_user_error(regs->uregs[20], &sf->uc.uc_mcontext.nds32_r20, err); + __get_user_error(regs->uregs[21], &sf->uc.uc_mcontext.nds32_r21, err); + __get_user_error(regs->uregs[22], &sf->uc.uc_mcontext.nds32_r22, err); + __get_user_error(regs->uregs[23], &sf->uc.uc_mcontext.nds32_r23, err); + __get_user_error(regs->uregs[24], &sf->uc.uc_mcontext.nds32_r24, err); + __get_user_error(regs->uregs[25], &sf->uc.uc_mcontext.nds32_r25, err); + + __get_user_error(regs->fp, &sf->uc.uc_mcontext.nds32_fp, err); + __get_user_error(regs->gp, &sf->uc.uc_mcontext.nds32_gp, err); + __get_user_error(regs->lp, &sf->uc.uc_mcontext.nds32_lp, err); + __get_user_error(regs->sp, &sf->uc.uc_mcontext.nds32_sp, err); + __get_user_error(regs->ipc, &sf->uc.uc_mcontext.nds32_ipc, err); +#if defined(CONFIG_HWZOL) + __get_user_error(regs->lc, &sf->uc.uc_mcontext.zol.nds32_lc, err); + __get_user_error(regs->le, &sf->uc.uc_mcontext.zol.nds32_le, err); + __get_user_error(regs->lb, &sf->uc.uc_mcontext.zol.nds32_lb, err); +#endif + + return err; +} + +asmlinkage long sys_rt_sigreturn(struct pt_regs *regs) +{ + struct rt_sigframe __user *frame; + + /* Always make any pending restarted system calls return -EINTR */ + current->restart_block.fn = do_no_restart_syscall; + + /* + * Since we stacked the signal on a 64-bit boundary, + * then 'sp' should be two-word aligned here. If it's + * not, then the user is trying to mess with us. + */ + if (regs->sp & 7) + goto badframe; + + frame = (struct rt_sigframe __user *)regs->sp; + + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + + if (restore_sigframe(regs, frame)) + goto badframe; + + if (restore_altstack(&frame->uc.uc_stack)) + goto badframe; + + return regs->uregs[0]; + +badframe: + force_sig(SIGSEGV, current); + return 0; +} + +static int +setup_sigframe(struct rt_sigframe __user * sf, struct pt_regs *regs, + sigset_t * set) +{ + int err = 0; + + + __put_user_error(regs->uregs[0], &sf->uc.uc_mcontext.nds32_r0, err); + __put_user_error(regs->uregs[1], &sf->uc.uc_mcontext.nds32_r1, err); + __put_user_error(regs->uregs[2], &sf->uc.uc_mcontext.nds32_r2, err); + __put_user_error(regs->uregs[3], &sf->uc.uc_mcontext.nds32_r3, err); + __put_user_error(regs->uregs[4], &sf->uc.uc_mcontext.nds32_r4, err); + __put_user_error(regs->uregs[5], &sf->uc.uc_mcontext.nds32_r5, err); + __put_user_error(regs->uregs[6], &sf->uc.uc_mcontext.nds32_r6, err); + __put_user_error(regs->uregs[7], &sf->uc.uc_mcontext.nds32_r7, err); + __put_user_error(regs->uregs[8], &sf->uc.uc_mcontext.nds32_r8, err); + __put_user_error(regs->uregs[9], &sf->uc.uc_mcontext.nds32_r9, err); + __put_user_error(regs->uregs[10], &sf->uc.uc_mcontext.nds32_r10, err); + __put_user_error(regs->uregs[11], &sf->uc.uc_mcontext.nds32_r11, err); + __put_user_error(regs->uregs[12], &sf->uc.uc_mcontext.nds32_r12, err); + __put_user_error(regs->uregs[13], &sf->uc.uc_mcontext.nds32_r13, err); + __put_user_error(regs->uregs[14], &sf->uc.uc_mcontext.nds32_r14, err); + __put_user_error(regs->uregs[15], &sf->uc.uc_mcontext.nds32_r15, err); + __put_user_error(regs->uregs[16], &sf->uc.uc_mcontext.nds32_r16, err); + __put_user_error(regs->uregs[17], &sf->uc.uc_mcontext.nds32_r17, err); + __put_user_error(regs->uregs[18], &sf->uc.uc_mcontext.nds32_r18, err); + __put_user_error(regs->uregs[19], &sf->uc.uc_mcontext.nds32_r19, err); + __put_user_error(regs->uregs[20], &sf->uc.uc_mcontext.nds32_r20, err); + + __put_user_error(regs->uregs[21], &sf->uc.uc_mcontext.nds32_r21, err); + __put_user_error(regs->uregs[22], &sf->uc.uc_mcontext.nds32_r22, err); + __put_user_error(regs->uregs[23], &sf->uc.uc_mcontext.nds32_r23, err); + __put_user_error(regs->uregs[24], &sf->uc.uc_mcontext.nds32_r24, err); + __put_user_error(regs->uregs[25], &sf->uc.uc_mcontext.nds32_r25, err); + __put_user_error(regs->fp, &sf->uc.uc_mcontext.nds32_fp, err); + __put_user_error(regs->gp, &sf->uc.uc_mcontext.nds32_gp, err); + __put_user_error(regs->lp, &sf->uc.uc_mcontext.nds32_lp, err); + __put_user_error(regs->sp, &sf->uc.uc_mcontext.nds32_sp, err); + __put_user_error(regs->ipc, &sf->uc.uc_mcontext.nds32_ipc, err); +#if defined(CONFIG_HWZOL) + __put_user_error(regs->lc, &sf->uc.uc_mcontext.zol.nds32_lc, err); + __put_user_error(regs->le, &sf->uc.uc_mcontext.zol.nds32_le, err); + __put_user_error(regs->lb, &sf->uc.uc_mcontext.zol.nds32_lb, err); +#endif + + __put_user_error(current->thread.trap_no, &sf->uc.uc_mcontext.trap_no, + err); + __put_user_error(current->thread.error_code, + &sf->uc.uc_mcontext.error_code, err); + __put_user_error(current->thread.address, + &sf->uc.uc_mcontext.fault_address, err); + __put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err); + + err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set)); + + return err; +} + +static inline void __user *get_sigframe(struct ksignal *ksig, + struct pt_regs *regs, int framesize) +{ + unsigned long sp = sigsp(regs->sp, ksig); + void __user *frame; + + /* + * nds32 mandates 8-byte alignment + */ + frame = (void __user *)((sp - framesize) & ~7); + + /* + * Check that we can actually write to the signal frame. + */ + if (!access_ok(VERIFY_WRITE, frame, framesize)) + frame = NULL; + + return frame; +} + +static int +setup_return(struct pt_regs *regs, struct ksignal *ksig, void __user * frame) +{ + unsigned long handler = (unsigned long)ksig->ka.sa.sa_handler; + unsigned long retcode; + + retcode = VDSO_SYMBOL(current->mm->context.vdso, rt_sigtramp); + regs->uregs[0] = ksig->sig; + regs->sp = (unsigned long)frame; + regs->lp = retcode; + regs->ipc = handler; + + return 0; +} + +static int +setup_rt_frame(struct ksignal *ksig, sigset_t * set, struct pt_regs *regs) +{ + struct rt_sigframe __user *frame = + get_sigframe(ksig, regs, sizeof(*frame)); + int err = 0; + + if (!frame) + return 1; + + err |= copy_siginfo_to_user(&frame->info, &ksig->info); + + __put_user_error(0, &frame->uc.uc_flags, err); + __put_user_error(NULL, &frame->uc.uc_link, err); + + err |= __save_altstack(&frame->uc.uc_stack, regs->sp); + err |= setup_sigframe(frame, regs, set); + if (err == 0) { + setup_return(regs, ksig, frame); + + if (err == 0) { + /* + * For realtime signals we must also set the second and third + * arguments for the signal handler. + * -- Peter Maydell <pmayd...@chiark.greenend.org.uk> 2000-12-06 + */ + regs->uregs[1] = (unsigned long)&frame->info; + regs->uregs[2] = (unsigned long)&frame->uc; + } + } + return err; +} + +/* + * 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); + + /* + * Check that the resulting registers are actually sane. + */ + ret |= !valid_user_regs(regs); + + signal_setup_done(ret, ksig, 0); +} + +/* + * Note that 'init' is a special process: it doesn't get signals it doesn't + * want to handle. Thus you cannot kill init even with a SIGKILL even by + * mistake. + * + * Note that we go through the signals twice: once to check the signals that + * the kernel can handle, and then we build all the user-level signal handling + * stack-frames in one go after that. + */ +static int do_signal(struct pt_regs *regs, int syscall) +{ + unsigned int retval = 0, continue_addr = 0, restart_addr = 0; + struct ksignal ksig; + int restart = 0; + + /* + * If we were from a system call, check for system call restarting... + */ + if (syscall) { + continue_addr = regs->ipc; + restart_addr = continue_addr - 4; + retval = regs->uregs[0]; + + /* + * Prepare for system call restart. We do this here so that a + * debugger will see the already changed PSW. + */ + switch (retval) { + case -ERESTART_RESTARTBLOCK: + restart -= 2; + case -ERESTARTNOHAND: + case -ERESTARTSYS: + case -ERESTARTNOINTR: + restart++; + regs->uregs[0] = regs->orig_r0; + regs->ipc = restart_addr; + break; + } + } + + /* + * Get the signal to deliver. When running under ptrace, at this + * point the debugger may change all our registers ... + */ + /* + * Depending on the signal settings we may need to revert the + * decision to restart the system call. But skip this if a + * debugger has chosen to restart at a different PC. + */ + if (get_signal(&ksig)) { + if (unlikely(restart) && regs->ipc == restart_addr) { + if (retval == -ERESTARTNOHAND || + retval == -ERESTART_RESTARTBLOCK + || (retval == -ERESTARTSYS + && !(ksig.ka.sa.sa_flags & SA_RESTART))) { + regs->uregs[0] = -EINTR; + regs->ipc = continue_addr; + } + } + handle_signal(&ksig, regs); + } else { + restore_saved_sigmask(); + if (unlikely(restart) && regs->ipc == restart_addr) { + regs->ipc = continue_addr; + return restart; + } + } + return 0; +} + +asmlinkage int +do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall) +{ + if (thread_flags & _TIF_SIGPENDING) + return do_signal(regs, syscall); + + if (thread_flags & _TIF_NOTIFY_RESUME) { + clear_thread_flag(TIF_NOTIFY_RESUME); + tracehook_notify_resume(regs); + } + return 0; +} -- 1.7.9.5
