diff options
Diffstat (limited to 'arch/mips/kernel/signal_n32.c')
| -rw-r--r-- | arch/mips/kernel/signal_n32.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/arch/mips/kernel/signal_n32.c b/arch/mips/kernel/signal_n32.c new file mode 100644 index 000000000..cfc77b694 --- /dev/null +++ b/arch/mips/kernel/signal_n32.c @@ -0,0 +1,148 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2003 Broadcom Corporation + */ +#include <linux/cache.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/errno.h> +#include <linux/wait.h> +#include <linux/ptrace.h> +#include <linux/unistd.h> +#include <linux/compat.h> +#include <linux/bitops.h> + +#include <asm/abi.h> +#include <asm/asm.h> +#include <asm/cacheflush.h> +#include <asm/compat-signal.h> +#include <asm/sim.h> +#include <linux/uaccess.h> +#include <asm/ucontext.h> +#include <asm/fpu.h> +#include <asm/cpu-features.h> + +#include "signal-common.h" + +/* + * Including <asm/unistd.h> would give use the 64-bit syscall numbers ... + */ +#define __NR_N32_restart_syscall 6214 + +extern int setup_sigcontext(struct pt_regs *, struct sigcontext __user *); +extern int restore_sigcontext(struct pt_regs *, struct sigcontext __user *); + +struct ucontextn32 { + u32 uc_flags; + s32 uc_link; + compat_stack_t uc_stack; + struct sigcontext uc_mcontext; + compat_sigset_t uc_sigmask; /* mask last for extensibility */ +}; + +struct rt_sigframe_n32 { + u32 rs_ass[4]; /* argument save space for o32 */ + u32 rs_pad[2]; /* Was: signal trampoline */ + struct compat_siginfo rs_info; + struct ucontextn32 rs_uc; +}; + +asmlinkage void sysn32_rt_sigreturn(void) +{ + struct rt_sigframe_n32 __user *frame; + struct pt_regs *regs; + sigset_t set; + int sig; + + regs = current_pt_regs(); + frame = (struct rt_sigframe_n32 __user *)regs->regs[29]; + if (!access_ok(frame, sizeof(*frame))) + goto badframe; + if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask)) + 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); + + if (compat_restore_altstack(&frame->rs_uc.uc_stack)) + goto badframe; + + /* + * Don't let your children do this ... + */ + __asm__ __volatile__( + "move\t$29, %0\n\t" + "j\tsyscall_exit" + : /* no outputs */ + : "r" (regs)); + /* Unreached */ + +badframe: + force_sig(SIGSEGV); +} + +static int setup_rt_frame_n32(void *sig_return, struct ksignal *ksig, + struct pt_regs *regs, sigset_t *set) +{ + struct rt_sigframe_n32 __user *frame; + int err = 0; + + frame = get_sigframe(ksig, regs, sizeof(*frame)); + if (!access_ok(frame, sizeof (*frame))) + return -EFAULT; + + /* Create siginfo. */ + err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info); + + /* Create the ucontext. */ + err |= __put_user(0, &frame->rs_uc.uc_flags); + err |= __put_user(0, &frame->rs_uc.uc_link); + err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]); + err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext); + err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set); + + if (err) + return -EFAULT; + + /* + * Arguments to signal handler: + * + * a0 = signal number + * a1 = 0 (should be cause) + * a2 = pointer to ucontext + * + * $25 and c0_epc point to the signal handler, $29 points to + * the struct rt_sigframe. + */ + 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) frame; + regs->regs[31] = (unsigned long) sig_return; + regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler; + + DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", + current->comm, current->pid, + frame, regs->cp0_epc, regs->regs[31]); + + return 0; +} + +struct mips_abi mips_abi_n32 = { + .setup_rt_frame = setup_rt_frame_n32, + .restart = __NR_N32_restart_syscall, + + .off_sc_fpregs = offsetof(struct sigcontext, sc_fpregs), + .off_sc_fpc_csr = offsetof(struct sigcontext, sc_fpc_csr), + .off_sc_used_math = offsetof(struct sigcontext, sc_used_math), + + .vdso = &vdso_image_n32, +}; |