| /* |
| * 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. |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| * Copyright (C) 1994 - 2000 Ralf Baechle |
| * Copyright (C) 1999, 2000 Silicon Graphics, Inc. |
| * Copyright (C) 2014, Imagination Technologies Ltd. |
| */ |
| #include <linux/cache.h> |
| #include <linux/context_tracking.h> |
| #include <linux/irqflags.h> |
| #include <linux/sched.h> |
| #include <linux/mm.h> |
| #include <linux/personality.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/uprobes.h> |
| #include <linux/compiler.h> |
| #include <linux/syscalls.h> |
| #include <linux/uaccess.h> |
| #include <linux/tracehook.h> |
| |
| #include <asm/abi.h> |
| #include <asm/asm.h> |
| #include <linux/bitops.h> |
| #include <asm/cacheflush.h> |
| #include <asm/fpu.h> |
| #include <asm/sim.h> |
| #include <asm/ucontext.h> |
| #include <asm/cpu-features.h> |
| #include <asm/war.h> |
| #include <asm/dsp.h> |
| #include <asm/inst.h> |
| #include <asm/msa.h> |
| |
| #include "signal-common.h" |
| |
| static int (*save_fp_context)(void __user *sc); |
| static int (*restore_fp_context)(void __user *sc); |
| |
| struct sigframe { |
| u32 sf_ass[4]; /* argument save space for o32 */ |
| u32 sf_pad[2]; /* Was: signal trampoline */ |
| |
| /* Matches struct ucontext from its uc_mcontext field onwards */ |
| struct sigcontext sf_sc; |
| sigset_t sf_mask; |
| unsigned long long sf_extcontext[0]; |
| }; |
| |
| struct rt_sigframe { |
| u32 rs_ass[4]; /* argument save space for o32 */ |
| u32 rs_pad[2]; /* Was: signal trampoline */ |
| struct siginfo rs_info; |
| struct ucontext rs_uc; |
| }; |
| |
| #ifdef CONFIG_MIPS_FP_SUPPORT |
| |
| /* |
| * Thread saved context copy to/from a signal context presumed to be on the |
| * user stack, and therefore accessed with appropriate macros from uaccess.h. |
| */ |
| static int copy_fp_to_sigcontext(void __user *sc) |
| { |
| struct mips_abi *abi = current->thread.abi; |
| uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| int i; |
| int err = 0; |
| int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1; |
| |
| for (i = 0; i < NUM_FPU_REGS; i += inc) { |
| err |= |
| __put_user(get_fpr64(¤t->thread.fpu.fpr[i], 0), |
| &fpregs[i]); |
| } |
| err |= __put_user(current->thread.fpu.fcr31, csr); |
| |
| return err; |
| } |
| |
| static int copy_fp_from_sigcontext(void __user *sc) |
| { |
| struct mips_abi *abi = current->thread.abi; |
| uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| int i; |
| int err = 0; |
| int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1; |
| u64 fpr_val; |
| |
| for (i = 0; i < NUM_FPU_REGS; i += inc) { |
| err |= __get_user(fpr_val, &fpregs[i]); |
| set_fpr64(¤t->thread.fpu.fpr[i], 0, fpr_val); |
| } |
| err |= __get_user(current->thread.fpu.fcr31, csr); |
| |
| return err; |
| } |
| |
| #else /* !CONFIG_MIPS_FP_SUPPORT */ |
| |
| static int copy_fp_to_sigcontext(void __user *sc) |
| { |
| return 0; |
| } |
| |
| static int copy_fp_from_sigcontext(void __user *sc) |
| { |
| return 0; |
| } |
| |
| #endif /* !CONFIG_MIPS_FP_SUPPORT */ |
| |
| /* |
| * Wrappers for the assembly _{save,restore}_fp_context functions. |
| */ |
| static int save_hw_fp_context(void __user *sc) |
| { |
| struct mips_abi *abi = current->thread.abi; |
| uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| |
| return _save_fp_context(fpregs, csr); |
| } |
| |
| static int restore_hw_fp_context(void __user *sc) |
| { |
| struct mips_abi *abi = current->thread.abi; |
| uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| |
| return _restore_fp_context(fpregs, csr); |
| } |
| |
| /* |
| * Extended context handling. |
| */ |
| |
| static inline void __user *sc_to_extcontext(void __user *sc) |
| { |
| struct ucontext __user *uc; |
| |
| /* |
| * We can just pretend the sigcontext is always embedded in a struct |
| * ucontext here, because the offset from sigcontext to extended |
| * context is the same in the struct sigframe case. |
| */ |
| uc = container_of(sc, struct ucontext, uc_mcontext); |
| return &uc->uc_extcontext; |
| } |
| |
| #ifdef CONFIG_CPU_HAS_MSA |
| |
| static int save_msa_extcontext(void __user *buf) |
| { |
| struct msa_extcontext __user *msa = buf; |
| uint64_t val; |
| int i, err; |
| |
| if (!thread_msa_context_live()) |
| return 0; |
| |
| /* |
| * Ensure that we can't lose the live MSA context between checking |
| * for it & writing it to memory. |
| */ |
| preempt_disable(); |
| |
| if (is_msa_enabled()) { |
| /* |
| * There are no EVA versions of the vector register load/store |
| * instructions, so MSA context has to be saved to kernel memory |
| * and then copied to user memory. The save to kernel memory |
| * should already have been done when handling scalar FP |
| * context. |
| */ |
| BUG_ON(IS_ENABLED(CONFIG_EVA)); |
| |
| err = __put_user(read_msa_csr(), &msa->csr); |
| err |= _save_msa_all_upper(&msa->wr); |
| |
| preempt_enable(); |
| } else { |
| preempt_enable(); |
| |
| err = __put_user(current->thread.fpu.msacsr, &msa->csr); |
| |
| for (i = 0; i < NUM_FPU_REGS; i++) { |
| val = get_fpr64(¤t->thread.fpu.fpr[i], 1); |
| err |= __put_user(val, &msa->wr[i]); |
| } |
| } |
| |
| err |= __put_user(MSA_EXTCONTEXT_MAGIC, &msa->ext.magic); |
| err |= __put_user(sizeof(*msa), &msa->ext.size); |
| |
| return err ? -EFAULT : sizeof(*msa); |
| } |
| |
| static int restore_msa_extcontext(void __user *buf, unsigned int size) |
| { |
| struct msa_extcontext __user *msa = buf; |
| unsigned long long val; |
| unsigned int csr; |
| int i, err; |
| |
| if (size != sizeof(*msa)) |
| return -EINVAL; |
| |
| err = get_user(csr, &msa->csr); |
| if (err) |
| return err; |
| |
| preempt_disable(); |
| |
| if (is_msa_enabled()) { |
| /* |
| * There are no EVA versions of the vector register load/store |
| * instructions, so MSA context has to be copied to kernel |
| * memory and later loaded to registers. The same is true of |
| * scalar FP context, so FPU & MSA should have already been |
| * disabled whilst handling scalar FP context. |
| */ |
| BUG_ON(IS_ENABLED(CONFIG_EVA)); |
| |
| write_msa_csr(csr); |
| err |= _restore_msa_all_upper(&msa->wr); |
| preempt_enable(); |
| } else { |
| preempt_enable(); |
| |
| current->thread.fpu.msacsr = csr; |
| |
| for (i = 0; i < NUM_FPU_REGS; i++) { |
| err |= __get_user(val, &msa->wr[i]); |
| set_fpr64(¤t->thread.fpu.fpr[i], 1, val); |
| } |
| } |
| |
| return err; |
| } |
| |
| #else /* !CONFIG_CPU_HAS_MSA */ |
| |
| static int save_msa_extcontext(void __user *buf) |
| { |
| return 0; |
| } |
| |
| static int restore_msa_extcontext(void __user *buf, unsigned int size) |
| { |
| return SIGSYS; |
| } |
| |
| #endif /* !CONFIG_CPU_HAS_MSA */ |
| |
| static int save_extcontext(void __user *buf) |
| { |
| int sz; |
| |
| sz = save_msa_extcontext(buf); |
| if (sz < 0) |
| return sz; |
| buf += sz; |
| |
| /* If no context was saved then trivially return */ |
| if (!sz) |
| return 0; |
| |
| /* Write the end marker */ |
| if (__put_user(END_EXTCONTEXT_MAGIC, (u32 *)buf)) |
| return -EFAULT; |
| |
| sz += sizeof(((struct extcontext *)NULL)->magic); |
| return sz; |
| } |
| |
| static int restore_extcontext(void __user *buf) |
| { |
| struct extcontext ext; |
| int err; |
| |
| while (1) { |
| err = __get_user(ext.magic, (unsigned int *)buf); |
| if (err) |
| return err; |
| |
| if (ext.magic == END_EXTCONTEXT_MAGIC) |
| return 0; |
| |
| err = __get_user(ext.size, (unsigned int *)(buf |
| + offsetof(struct extcontext, size))); |
| if (err) |
| return err; |
| |
| switch (ext.magic) { |
| case MSA_EXTCONTEXT_MAGIC: |
| err = restore_msa_extcontext(buf, ext.size); |
| break; |
| |
| default: |
| err = -EINVAL; |
| break; |
| } |
| |
| if (err) |
| return err; |
| |
| buf += ext.size; |
| } |
| } |
| |
| /* |
| * Helper routines |
| */ |
| int protected_save_fp_context(void __user *sc) |
| { |
| struct mips_abi *abi = current->thread.abi; |
| uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| uint32_t __user *used_math = sc + abi->off_sc_used_math; |
| unsigned int used, ext_sz; |
| int err; |
| |
| used = used_math() ? USED_FP : 0; |
| if (!used) |
| goto fp_done; |
| |
| if (!test_thread_flag(TIF_32BIT_FPREGS)) |
| used |= USED_FR1; |
| if (test_thread_flag(TIF_HYBRID_FPREGS)) |
| used |= USED_HYBRID_FPRS; |
| |
| /* |
| * EVA does not have userland equivalents of ldc1 or sdc1, so |
| * save to the kernel FP context & copy that to userland below. |
| */ |
| if (IS_ENABLED(CONFIG_EVA)) |
| lose_fpu(1); |
| |
| while (1) { |
| lock_fpu_owner(); |
| if (is_fpu_owner()) { |
| err = save_fp_context(sc); |
| unlock_fpu_owner(); |
| } else { |
| unlock_fpu_owner(); |
| err = copy_fp_to_sigcontext(sc); |
| } |
| if (likely(!err)) |
| break; |
| /* touch the sigcontext and try again */ |
| err = __put_user(0, &fpregs[0]) | |
| __put_user(0, &fpregs[31]) | |
| __put_user(0, csr); |
| if (err) |
| return err; /* really bad sigcontext */ |
| } |
| |
| fp_done: |
| ext_sz = err = save_extcontext(sc_to_extcontext(sc)); |
| if (err < 0) |
| return err; |
| used |= ext_sz ? USED_EXTCONTEXT : 0; |
| |
| return __put_user(used, used_math); |
| } |
| |
| int protected_restore_fp_context(void __user *sc) |
| { |
| struct mips_abi *abi = current->thread.abi; |
| uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| uint32_t __user *used_math = sc + abi->off_sc_used_math; |
| unsigned int used; |
| int err, sig = 0, tmp __maybe_unused; |
| |
| err = __get_user(used, used_math); |
| conditional_used_math(used & USED_FP); |
| |
| /* |
| * The signal handler may have used FPU; give it up if the program |
| * doesn't want it following sigreturn. |
| */ |
| if (err || !(used & USED_FP)) |
| lose_fpu(0); |
| if (err) |
| return err; |
| if (!(used & USED_FP)) |
| goto fp_done; |
| |
| err = sig = fpcsr_pending(csr); |
| if (err < 0) |
| return err; |
| |
| /* |
| * EVA does not have userland equivalents of ldc1 or sdc1, so we |
| * disable the FPU here such that the code below simply copies to |
| * the kernel FP context. |
| */ |
| if (IS_ENABLED(CONFIG_EVA)) |
| lose_fpu(0); |
| |
| while (1) { |
| lock_fpu_owner(); |
| if (is_fpu_owner()) { |
| err = restore_fp_context(sc); |
| unlock_fpu_owner(); |
| } else { |
| unlock_fpu_owner(); |
| err = copy_fp_from_sigcontext(sc); |
| } |
| if (likely(!err)) |
| break; |
| /* touch the sigcontext and try again */ |
| err = __get_user(tmp, &fpregs[0]) | |
| __get_user(tmp, &fpregs[31]) | |
| __get_user(tmp, csr); |
| if (err) |
| break; /* really bad sigcontext */ |
| } |
| |
| fp_done: |
| if (!err && (used & USED_EXTCONTEXT)) |
| err = restore_extcontext(sc_to_extcontext(sc)); |
| |
| return err ?: sig; |
| } |
| |
| int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) |
| { |
| int err = 0; |
| int i; |
| |
| err |= __put_user(regs->cp0_epc, &sc->sc_pc); |
| |
| err |= __put_user(0, &sc->sc_regs[0]); |
| for (i = 1; i < 32; i++) |
| err |= __put_user(regs->regs[i], &sc->sc_regs[i]); |
| |
| #ifdef CONFIG_CPU_HAS_SMARTMIPS |
| err |= __put_user(regs->acx, &sc->sc_acx); |
| #endif |
| err |= __put_user(regs->hi, &sc->sc_mdhi); |
| err |= __put_user(regs->lo, &sc->sc_mdlo); |
| if (cpu_has_dsp) { |
| err |= __put_user(mfhi1(), &sc->sc_hi1); |
| err |= __put_user(mflo1(), &sc->sc_lo1); |
| err |= __put_user(mfhi2(), &sc->sc_hi2); |
| err |= __put_user(mflo2(), &sc->sc_lo2); |
| err |= __put_user(mfhi3(), &sc->sc_hi3); |
| err |= __put_user(mflo3(), &sc->sc_lo3); |
| err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp); |
| } |
| |
| |
| /* |
| * Save FPU state to signal context. Signal handler |
| * will "inherit" current FPU state. |
| */ |
| err |= protected_save_fp_context(sc); |
| |
| return err; |
| } |
| |
| static size_t extcontext_max_size(void) |
| { |
| size_t sz = 0; |
| |
| /* |
| * The assumption here is that between this point & the point at which |
| * the extended context is saved the size of the context should only |
| * ever be able to shrink (if the task is preempted), but never grow. |
| * That is, what this function returns is an upper bound on the size of |
| * the extended context for the current task at the current time. |
| */ |
| |
| if (thread_msa_context_live()) |
| sz += sizeof(struct msa_extcontext); |
| |
| /* If any context is saved then we'll append the end marker */ |
| if (sz) |
| sz += sizeof(((struct extcontext *)NULL)->magic); |
| |
| return sz; |
| } |
| |
| int fpcsr_pending(unsigned int __user *fpcsr) |
| { |
| int err, sig = 0; |
| unsigned int csr, enabled; |
| |
| err = __get_user(csr, fpcsr); |
| enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5); |
| /* |
| * If the signal handler set some FPU exceptions, clear it and |
| * send SIGFPE. |
| */ |
| if (csr & enabled) { |
| csr &= ~enabled; |
| err |= __put_user(csr, fpcsr); |
| sig = SIGFPE; |
| } |
| return err ?: sig; |
| } |
| |
| int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) |
| { |
| unsigned long treg; |
| int err = 0; |
| int i; |
| |
| /* Always make any pending restarted system calls return -EINTR */ |
| current->restart_block.fn = do_no_restart_syscall; |
| |
| err |= __get_user(regs->cp0_epc, &sc->sc_pc); |
| |
| #ifdef CONFIG_CPU_HAS_SMARTMIPS |
| err |= __get_user(regs->acx, &sc->sc_acx); |
| #endif |
| err |= __get_user(regs->hi, &sc->sc_mdhi); |
| err |= __get_user(regs->lo, &sc->sc_mdlo); |
| if (cpu_has_dsp) { |
| err |= __get_user(treg, &sc->sc_hi1); mthi1(treg); |
| err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg); |
| err |= __get_user(treg, &sc->sc_hi2); mthi2(treg); |
| err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg); |
| err |= __get_user(treg, &sc->sc_hi3); mthi3(treg); |
| err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg); |
| err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK); |
| } |
| |
| for (i = 1; i < 32; i++) |
| err |= __get_user(regs->regs[i], &sc->sc_regs[i]); |
| |
| return err ?: protected_restore_fp_context(sc); |
| } |
| |
| void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, |
| size_t frame_size) |
| { |
| unsigned long sp; |
| |
| /* Leave space for potential extended context */ |
| frame_size += extcontext_max_size(); |
| |
| /* Default to using normal stack */ |
| sp = regs->regs[29]; |
| |
| /* |
| * FPU emulator may have it's own trampoline active just |
| * above the user stack, 16-bytes before the next lowest |
| * 16 byte boundary. Try to avoid trashing it. |
| */ |
| sp -= 32; |
| |
| sp = sigsp(sp, ksig); |
| |
| return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK)); |
| } |
| |
| /* |
| * Atomically swap in the new signal mask, and wait for a signal. |
| */ |
| |
| #ifdef CONFIG_TRAD_SIGNALS |
| SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset) |
| { |
| return sys_rt_sigsuspend(uset, sizeof(sigset_t)); |
| } |
| #endif |
| |
| #ifdef CONFIG_TRAD_SIGNALS |
| SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act, |
| struct sigaction __user *, oact) |
| { |
| struct k_sigaction new_ka, old_ka; |
| int ret; |
| int err = 0; |
| |
| if (act) { |
| old_sigset_t mask; |
| |
| if (!access_ok(VERIFY_READ, act, sizeof(*act))) |
| return -EFAULT; |
| err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler); |
| err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags); |
| err |= __get_user(mask, &act->sa_mask.sig[0]); |
| if (err) |
| return -EFAULT; |
| |
| siginitset(&new_ka.sa.sa_mask, mask); |
| } |
| |
| ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); |
| |
| if (!ret && oact) { |
| if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact))) |
| return -EFAULT; |
| err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags); |
| err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler); |
| err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig); |
| err |= __put_user(0, &oact->sa_mask.sig[1]); |
| err |= __put_user(0, &oact->sa_mask.sig[2]); |
| err |= __put_user(0, &oact->sa_mask.sig[3]); |
| if (err) |
| return -EFAULT; |
| } |
| |
| return ret; |
| } |
| #endif |
| |
| #ifdef CONFIG_TRAD_SIGNALS |
| asmlinkage void sys_sigreturn(void) |
| { |
| struct sigframe __user *frame; |
| struct pt_regs *regs; |
| sigset_t blocked; |
| int sig; |
| |
| regs = current_pt_regs(); |
| frame = (struct sigframe __user *)regs->regs[29]; |
| if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
| goto badframe; |
| if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked))) |
| goto badframe; |
| |
| set_current_blocked(&blocked); |
| |
| sig = restore_sigcontext(regs, &frame->sf_sc); |
| if (sig < 0) |
| goto badframe; |
| else if (sig) |
| force_sig(sig, current); |
| |
| /* |
| * 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, current); |
| } |
| #endif /* CONFIG_TRAD_SIGNALS */ |
| |
| asmlinkage void sys_rt_sigreturn(void) |
| { |
| struct rt_sigframe __user *frame; |
| struct pt_regs *regs; |
| sigset_t set; |
| int sig; |
| |
| regs = current_pt_regs(); |
| frame = (struct rt_sigframe __user *)regs->regs[29]; |
| 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; |
| |
| /* |
| * 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, current); |
| } |
| |
| #ifdef CONFIG_TRAD_SIGNALS |
| static int setup_frame(void *sig_return, struct ksignal *ksig, |
| struct pt_regs *regs, sigset_t *set) |
| { |
| struct sigframe __user *frame; |
| int err = 0; |
| |
| frame = get_sigframe(ksig, regs, sizeof(*frame)); |
| if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) |
| return -EFAULT; |
| |
| err |= setup_sigcontext(regs, &frame->sf_sc); |
| err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set)); |
| if (err) |
| return -EFAULT; |
| |
| /* |
| * Arguments to signal handler: |
| * |
| * a0 = signal number |
| * a1 = 0 (should be cause) |
| * a2 = pointer to struct sigcontext |
| * |
| * $25 and c0_epc point to the signal handler, $29 points to the |
| * struct sigframe. |
| */ |
| regs->regs[ 4] = ksig->sig; |
| regs->regs[ 5] = 0; |
| regs->regs[ 6] = (unsigned long) &frame->sf_sc; |
| 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; |
| } |
| #endif |
| |
| static int setup_rt_frame(void *sig_return, struct ksignal *ksig, |
| struct pt_regs *regs, sigset_t *set) |
| { |
| struct rt_sigframe __user *frame; |
| int err = 0; |
| |
| frame = get_sigframe(ksig, regs, sizeof(*frame)); |
| if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) |
| return -EFAULT; |
| |
| /* Create siginfo. */ |
| err |= copy_siginfo_to_user(&frame->rs_info, &ksig->info); |
| |
| /* Create the ucontext. */ |
| 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[29]); |
| 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; |
| |
| /* |
| * 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 = { |
| #ifdef CONFIG_TRAD_SIGNALS |
| .setup_frame = setup_frame, |
| #endif |
| .setup_rt_frame = setup_rt_frame, |
| .restart = __NR_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, |
| }; |
| |
| static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
| { |
| sigset_t *oldset = sigmask_to_save(); |
| int ret; |
| struct mips_abi *abi = current->thread.abi; |
| void *vdso = current->mm->context.vdso; |
| |
| /* |
| * If we were emulating a delay slot instruction, exit that frame such |
| * that addresses in the sigframe are as expected for userland and we |
| * don't have a problem if we reuse the thread's frame for an |
| * instruction within the signal handler. |
| */ |
| dsemul_thread_rollback(regs); |
| |
| if (regs->regs[0]) { |
| switch(regs->regs[2]) { |
| case ERESTART_RESTARTBLOCK: |
| case ERESTARTNOHAND: |
| regs->regs[2] = EINTR; |
| break; |
| case ERESTARTSYS: |
| if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { |
| regs->regs[2] = EINTR; |
| break; |
| } |
| /* fallthrough */ |
| case ERESTARTNOINTR: |
| regs->regs[7] = regs->regs[26]; |
| regs->regs[2] = regs->regs[0]; |
| regs->cp0_epc -= 4; |
| } |
| |
| regs->regs[0] = 0; /* Don't deal with this again. */ |
| } |
| |
| rseq_signal_deliver(ksig, regs); |
| |
| if (sig_uses_siginfo(&ksig->ka, abi)) |
| ret = abi->setup_rt_frame(vdso + abi->vdso->off_rt_sigreturn, |
| ksig, regs, oldset); |
| else |
| ret = abi->setup_frame(vdso + abi->vdso->off_sigreturn, |
| ksig, regs, oldset); |
| |
| signal_setup_done(ret, ksig, 0); |
| } |
| |
| static void do_signal(struct pt_regs *regs) |
| { |
| struct ksignal ksig; |
| |
| if (get_signal(&ksig)) { |
| /* Whee! Actually deliver the signal. */ |
| handle_signal(&ksig, regs); |
| return; |
| } |
| |
| if (regs->regs[0]) { |
| switch (regs->regs[2]) { |
| case ERESTARTNOHAND: |
| case ERESTARTSYS: |
| case ERESTARTNOINTR: |
| regs->regs[2] = regs->regs[0]; |
| regs->regs[7] = regs->regs[26]; |
| regs->cp0_epc -= 4; |
| break; |
| |
| case ERESTART_RESTARTBLOCK: |
| regs->regs[2] = current->thread.abi->restart; |
| regs->regs[7] = regs->regs[26]; |
| regs->cp0_epc -= 4; |
| break; |
| } |
| regs->regs[0] = 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) |
| { |
| local_irq_enable(); |
| |
| user_exit(); |
| |
| if (thread_info_flags & _TIF_UPROBE) |
| uprobe_notify_resume(regs); |
| |
| /* 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); |
| rseq_handle_notify_resume(NULL, regs); |
| } |
| |
| user_enter(); |
| } |
| |
| #if defined(CONFIG_SMP) && defined(CONFIG_MIPS_FP_SUPPORT) |
| static int smp_save_fp_context(void __user *sc) |
| { |
| return raw_cpu_has_fpu |
| ? save_hw_fp_context(sc) |
| : copy_fp_to_sigcontext(sc); |
| } |
| |
| static int smp_restore_fp_context(void __user *sc) |
| { |
| return raw_cpu_has_fpu |
| ? restore_hw_fp_context(sc) |
| : copy_fp_from_sigcontext(sc); |
| } |
| #endif |
| |
| static int signal_setup(void) |
| { |
| /* |
| * The offset from sigcontext to extended context should be the same |
| * regardless of the type of signal, such that userland can always know |
| * where to look if it wishes to find the extended context structures. |
| */ |
| BUILD_BUG_ON((offsetof(struct sigframe, sf_extcontext) - |
| offsetof(struct sigframe, sf_sc)) != |
| (offsetof(struct rt_sigframe, rs_uc.uc_extcontext) - |
| offsetof(struct rt_sigframe, rs_uc.uc_mcontext))); |
| |
| #if defined(CONFIG_SMP) && defined(CONFIG_MIPS_FP_SUPPORT) |
| /* For now just do the cpu_has_fpu check when the functions are invoked */ |
| save_fp_context = smp_save_fp_context; |
| restore_fp_context = smp_restore_fp_context; |
| #else |
| if (cpu_has_fpu) { |
| save_fp_context = save_hw_fp_context; |
| restore_fp_context = restore_hw_fp_context; |
| } else { |
| save_fp_context = copy_fp_to_sigcontext; |
| restore_fp_context = copy_fp_from_sigcontext; |
| } |
| #endif /* CONFIG_SMP */ |
| |
| return 0; |
| } |
| |
| arch_initcall(signal_setup); |