diff options
Diffstat (limited to 'arch/score/kernel/signal.c')
| -rw-r--r-- | arch/score/kernel/signal.c | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/arch/score/kernel/signal.c b/arch/score/kernel/signal.c new file mode 100644 index 000000000..e381c8c4f --- /dev/null +++ b/arch/score/kernel/signal.c @@ -0,0 +1,308 @@ +/* + * arch/score/kernel/signal.c + * + * Score Processor version. + * + * Copyright (C) 2009 Sunplus Core Technology Co., Ltd. + * Chen Liqin <liqin.chen@sunplusct.com> + * Lennox Wu <lennox.wu@sunplusct.com> + * + * 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. 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 the file COPYING, or write + * to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <linux/errno.h> +#include <linux/signal.h> +#include <linux/ptrace.h> +#include <linux/unistd.h> +#include <linux/uaccess.h> +#include <linux/tracehook.h> + +#include <asm/cacheflush.h> +#include <asm/syscalls.h> +#include <asm/ucontext.h> + +struct rt_sigframe { + u32 rs_ass[4]; /* argument save space */ + u32 rs_code[2]; /* signal trampoline */ + struct siginfo rs_info; + struct ucontext rs_uc; +}; + +static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) +{ + int err = 0; + unsigned long reg; + + reg = regs->cp0_epc; err |= __put_user(reg, &sc->sc_pc); + err |= __put_user(regs->cp0_psr, &sc->sc_psr); + err |= __put_user(regs->cp0_condition, &sc->sc_condition); + + +#define save_gp_reg(i) { \ + reg = regs->regs[i]; \ + err |= __put_user(reg, &sc->sc_regs[i]); \ +} while (0) + save_gp_reg(0); save_gp_reg(1); save_gp_reg(2); + save_gp_reg(3); save_gp_reg(4); save_gp_reg(5); + save_gp_reg(6); save_gp_reg(7); save_gp_reg(8); + save_gp_reg(9); save_gp_reg(10); save_gp_reg(11); + save_gp_reg(12); save_gp_reg(13); save_gp_reg(14); + save_gp_reg(15); save_gp_reg(16); save_gp_reg(17); + save_gp_reg(18); save_gp_reg(19); save_gp_reg(20); + save_gp_reg(21); save_gp_reg(22); save_gp_reg(23); + save_gp_reg(24); save_gp_reg(25); save_gp_reg(26); + save_gp_reg(27); save_gp_reg(28); save_gp_reg(29); +#undef save_gp_reg + + reg = regs->ceh; err |= __put_user(reg, &sc->sc_mdceh); + reg = regs->cel; err |= __put_user(reg, &sc->sc_mdcel); + err |= __put_user(regs->cp0_ecr, &sc->sc_ecr); + err |= __put_user(regs->cp0_ema, &sc->sc_ema); + + return err; +} + +static int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) +{ + int err = 0; + u32 reg; + + err |= __get_user(regs->cp0_epc, &sc->sc_pc); + err |= __get_user(regs->cp0_condition, &sc->sc_condition); + + err |= __get_user(reg, &sc->sc_mdceh); + regs->ceh = (int) reg; + err |= __get_user(reg, &sc->sc_mdcel); + regs->cel = (int) reg; + + err |= __get_user(reg, &sc->sc_psr); + regs->cp0_psr = (int) reg; + err |= __get_user(reg, &sc->sc_ecr); + regs->cp0_ecr = (int) reg; + err |= __get_user(reg, &sc->sc_ema); + regs->cp0_ema = (int) reg; + +#define restore_gp_reg(i) do { \ + err |= __get_user(reg, &sc->sc_regs[i]); \ + regs->regs[i] = reg; \ +} while (0) + restore_gp_reg(0); restore_gp_reg(1); restore_gp_reg(2); + restore_gp_reg(3); restore_gp_reg(4); restore_gp_reg(5); + restore_gp_reg(6); restore_gp_reg(7); restore_gp_reg(8); + restore_gp_reg(9); restore_gp_reg(10); restore_gp_reg(11); + restore_gp_reg(12); restore_gp_reg(13); restore_gp_reg(14); + restore_gp_reg(15); restore_gp_reg(16); restore_gp_reg(17); + restore_gp_reg(18); restore_gp_reg(19); restore_gp_reg(20); + restore_gp_reg(21); restore_gp_reg(22); restore_gp_reg(23); + restore_gp_reg(24); restore_gp_reg(25); restore_gp_reg(26); + restore_gp_reg(27); restore_gp_reg(28); restore_gp_reg(29); +#undef restore_gp_reg + + return err; +} + +/* + * Determine which stack to use.. + */ +static void __user *get_sigframe(struct k_sigaction *ka, + struct pt_regs *regs, size_t frame_size) +{ + unsigned long sp; + + /* Default to using normal stack */ + sp = regs->regs[0]; + sp -= 32; + + /* This is the X/Open sanctioned signal stack switching. */ + if ((ka->sa.sa_flags & SA_ONSTACK) && (!on_sig_stack(sp))) + sp = current->sas_ss_sp + current->sas_ss_size; + + return (void __user*)((sp - frame_size) & ~7); +} + +asmlinkage long +score_rt_sigreturn(struct pt_regs *regs) +{ + struct rt_sigframe __user *frame; + sigset_t set; + int sig; + + /* Always make any pending restarted system calls return -EINTR */ + current->restart_block.fn = do_no_restart_syscall; + + frame = (struct rt_sigframe __user *) regs->regs[0]; + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set))) + goto badframe; + + set_current_blocked(&set); + + sig = restore_sigcontext(regs, &frame->rs_uc.uc_mcontext); + if (sig < 0) + goto badframe; + else if (sig) + force_sig(sig, current); + + if (restore_altstack(&frame->rs_uc.uc_stack)) + goto badframe; + regs->is_syscall = 0; + + __asm__ __volatile__( + "mv\tr0, %0\n\t" + "la\tr8, syscall_exit\n\t" + "br\tr8\n\t" + : : "r" (regs) : "r8"); + +badframe: + force_sig(SIGSEGV, current); + + return 0; +} + +static int setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs, + sigset_t *set) +{ + struct rt_sigframe __user *frame; + int err = 0; + + frame = get_sigframe(&ksig->ka, regs, sizeof(*frame)); + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + return -EFAULT; + + /* + * Set up the return code ... + * + * li v0, __NR_rt_sigreturn + * syscall + */ + err |= __put_user(0x87788000 + __NR_rt_sigreturn*2, + frame->rs_code + 0); + err |= __put_user(0x80008002, frame->rs_code + 1); + flush_cache_sigtramp((unsigned long) frame->rs_code); + + err |= copy_siginfo_to_user(&frame->rs_info, &ksig->info); + err |= __put_user(0, &frame->rs_uc.uc_flags); + err |= __put_user(NULL, &frame->rs_uc.uc_link); + err |= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[0]); + err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext); + err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set)); + + if (err) + return -EFAULT; + + regs->regs[0] = (unsigned long) frame; + regs->regs[3] = (unsigned long) frame->rs_code; + regs->regs[4] = ksig->sig; + regs->regs[5] = (unsigned long) &frame->rs_info; + regs->regs[6] = (unsigned long) &frame->rs_uc; + regs->regs[29] = (unsigned long) ksig->ka.sa.sa_handler; + regs->cp0_epc = (unsigned long) ksig->ka.sa.sa_handler; + + return 0; +} + +static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) +{ + int ret; + + if (regs->is_syscall) { + switch (regs->regs[4]) { + case ERESTART_RESTARTBLOCK: + case ERESTARTNOHAND: + regs->regs[4] = EINTR; + break; + case ERESTARTSYS: + if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { + regs->regs[4] = EINTR; + break; + } + case ERESTARTNOINTR: + regs->regs[4] = regs->orig_r4; + regs->regs[7] = regs->orig_r7; + regs->cp0_epc -= 8; + } + + regs->is_syscall = 0; + } + + /* + * Set up the stack frame + */ + ret = setup_rt_frame(ksig, regs, sigmask_to_save()); + + signal_setup_done(ret, ksig, 0); +} + +static void do_signal(struct pt_regs *regs) +{ + struct ksignal ksig; + + /* + * 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 (get_signal(&ksig)) { + /* Actually deliver the signal. */ + handle_signal(&ksig, regs); + return; + } + + if (regs->is_syscall) { + if (regs->regs[4] == ERESTARTNOHAND || + regs->regs[4] == ERESTARTSYS || + regs->regs[4] == ERESTARTNOINTR) { + regs->regs[4] = regs->orig_r4; + regs->regs[7] = regs->orig_r7; + regs->cp0_epc -= 8; + } + + if (regs->regs[4] == ERESTART_RESTARTBLOCK) { + regs->regs[27] = __NR_restart_syscall; + regs->regs[4] = regs->orig_r4; + regs->regs[7] = regs->orig_r7; + regs->cp0_epc -= 8; + } + + regs->is_syscall = 0; /* Don't deal with this again. */ + } + + /* + * If there's no signal to deliver, we just put the saved sigmask + * back + */ + restore_saved_sigmask(); +} + +/* + * notification of userspace execution resumption + * - triggered by the TIF_WORK_MASK flags + */ +asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused, + __u32 thread_info_flags) +{ + /* deal with pending signal delivery */ + if (thread_info_flags & _TIF_SIGPENDING) + do_signal(regs); + if (thread_info_flags & _TIF_NOTIFY_RESUME) { + clear_thread_flag(TIF_NOTIFY_RESUME); + tracehook_notify_resume(regs); + } +} |