From 30b7f2b9dea3b2ec03a0b2b0f82b93e4e06ba62e Mon Sep 17 00:00:00 2001 From: Andreas Schwab Date: Fri, 9 Aug 2013 14:19:02 +0100 Subject: linux-user: Add signal handling for AArch64 This patch adds signal handling for AArch64. The code is based on the respective source in the Linux kernel. Signed-off-by: Andreas Schwab Signed-off-by: Alexander Graf Signed-off-by: John Rigby Message-id: 1368505980-17151-10-git-send-email-john.rigby@linaro.org [PMM: fixed style nits: tabs, long lines; pulled target_signal.h in from a later patch; it fits better here] Signed-off-by: Peter Maydell --- linux-user/aarch64/target_signal.h | 29 +++++ linux-user/signal.c | 260 +++++++++++++++++++++++++++++++++++++ 2 files changed, 289 insertions(+) create mode 100644 linux-user/aarch64/target_signal.h diff --git a/linux-user/aarch64/target_signal.h b/linux-user/aarch64/target_signal.h new file mode 100644 index 0000000000..e8c677de11 --- /dev/null +++ b/linux-user/aarch64/target_signal.h @@ -0,0 +1,29 @@ +#ifndef TARGET_SIGNAL_H +#define TARGET_SIGNAL_H + +#include "cpu.h" + +/* this struct defines a stack used during syscall handling */ + +typedef struct target_sigaltstack { + abi_ulong ss_sp; + abi_int ss_flags; + abi_ulong ss_size; +} target_stack_t; + + +/* + * sigaltstack controls + */ +#define TARGET_SS_ONSTACK 1 +#define TARGET_SS_DISABLE 2 + +#define TARGET_MINSIGSTKSZ 2048 +#define TARGET_SIGSTKSZ 8192 + +static inline abi_ulong get_sp_from_cpustate(CPUARMState *state) +{ + return state->xregs[31]; +} + +#endif /* TARGET_SIGNAL_H */ diff --git a/linux-user/signal.c b/linux-user/signal.c index 23d65dab77..7751c47ef1 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -1092,6 +1092,266 @@ badframe: return 0; } +#elif defined(TARGET_AARCH64) + +struct target_sigcontext { + uint64_t fault_address; + /* AArch64 registers */ + uint64_t regs[31]; + uint64_t sp; + uint64_t pc; + uint64_t pstate; + /* 4K reserved for FP/SIMD state and future expansion */ + char __reserved[4096] __attribute__((__aligned__(16))); +}; + +struct target_ucontext { + abi_ulong tuc_flags; + abi_ulong tuc_link; + target_stack_t tuc_stack; + target_sigset_t tuc_sigmask; + /* glibc uses a 1024-bit sigset_t */ + char __unused[1024 / 8 - sizeof(target_sigset_t)]; + /* last for future expansion */ + struct target_sigcontext tuc_mcontext; +}; + +/* + * Header to be used at the beginning of structures extending the user + * context. Such structures must be placed after the rt_sigframe on the stack + * and be 16-byte aligned. The last structure must be a dummy one with the + * magic and size set to 0. + */ +struct target_aarch64_ctx { + uint32_t magic; + uint32_t size; +}; + +#define TARGET_FPSIMD_MAGIC 0x46508001 + +struct target_fpsimd_context { + struct target_aarch64_ctx head; + uint32_t fpsr; + uint32_t fpcr; + uint64_t vregs[32 * 2]; /* really uint128_t vregs[32] */ +}; + +/* + * Auxiliary context saved in the sigcontext.__reserved array. Not exported to + * user space as it will change with the addition of new context. User space + * should check the magic/size information. + */ +struct target_aux_context { + struct target_fpsimd_context fpsimd; + /* additional context to be added before "end" */ + struct target_aarch64_ctx end; +}; + +struct target_rt_sigframe { + struct target_siginfo info; + struct target_ucontext uc; + uint64_t fp; + uint64_t lr; + uint32_t tramp[2]; +}; + +static int target_setup_sigframe(struct target_rt_sigframe *sf, + CPUARMState *env, target_sigset_t *set) +{ + int i; + struct target_aux_context *aux = + (struct target_aux_context *)sf->uc.tuc_mcontext.__reserved; + + /* set up the stack frame for unwinding */ + __put_user(env->xregs[29], &sf->fp); + __put_user(env->xregs[30], &sf->lr); + + for (i = 0; i < 31; i++) { + __put_user(env->xregs[i], &sf->uc.tuc_mcontext.regs[i]); + } + __put_user(env->xregs[31], &sf->uc.tuc_mcontext.sp); + __put_user(env->pc, &sf->uc.tuc_mcontext.pc); + __put_user(env->pstate, &sf->uc.tuc_mcontext.pstate); + + __put_user(/*current->thread.fault_address*/ 0, + &sf->uc.tuc_mcontext.fault_address); + + for (i = 0; i < TARGET_NSIG_WORDS; i++) { + __put_user(set->sig[i], &sf->uc.tuc_sigmask.sig[i]); + } + + for (i = 0; i < 32; i++) { +#ifdef TARGET_WORDS_BIGENDIAN + __put_user(env->vfp.regs[i * 2], &aux->fpsimd.vregs[i * 2 + 1]); + __put_user(env->vfp.regs[i * 2 + 1], &aux->fpsimd.vregs[i * 2]); +#else + __put_user(env->vfp.regs[i * 2], &aux->fpsimd.vregs[i * 2]); + __put_user(env->vfp.regs[i * 2 + 1], &aux->fpsimd.vregs[i * 2 + 1]); +#endif + } + __put_user(/*env->fpsr*/0, &aux->fpsimd.fpsr); + __put_user(/*env->fpcr*/0, &aux->fpsimd.fpcr); + __put_user(TARGET_FPSIMD_MAGIC, &aux->fpsimd.head.magic); + __put_user(sizeof(struct target_fpsimd_context), + &aux->fpsimd.head.size); + + /* set the "end" magic */ + __put_user(0, &aux->end.magic); + __put_user(0, &aux->end.size); + + return 0; +} + +static int target_restore_sigframe(CPUARMState *env, + struct target_rt_sigframe *sf) +{ + sigset_t set; + int i; + struct target_aux_context *aux = + (struct target_aux_context *)sf->uc.tuc_mcontext.__reserved; + uint32_t magic, size; + + target_to_host_sigset(&set, &sf->uc.tuc_sigmask); + sigprocmask(SIG_SETMASK, &set, NULL); + + for (i = 0; i < 31; i++) { + __get_user(env->xregs[i], &sf->uc.tuc_mcontext.regs[i]); + } + + __get_user(env->xregs[31], &sf->uc.tuc_mcontext.sp); + __get_user(env->pc, &sf->uc.tuc_mcontext.pc); + __get_user(env->pstate, &sf->uc.tuc_mcontext.pstate); + + __get_user(magic, &aux->fpsimd.head.magic); + __get_user(size, &aux->fpsimd.head.size); + + if (magic != TARGET_FPSIMD_MAGIC + || size != sizeof(struct target_fpsimd_context)) { + return 1; + } + + for (i = 0; i < 32 * 2; i++) { + __get_user(env->vfp.regs[i], &aux->fpsimd.vregs[i]); + } + + return 0; +} + +static abi_ulong get_sigframe(struct target_sigaction *ka, CPUARMState *env) +{ + abi_ulong sp; + + sp = env->xregs[31]; + + /* + * This is the X/Open sanctioned signal stack switching. + */ + if ((ka->sa_flags & SA_ONSTACK) && !sas_ss_flags(sp)) { + sp = target_sigaltstack_used.ss_sp + target_sigaltstack_used.ss_size; + } + + sp = (sp - sizeof(struct target_rt_sigframe)) & ~15; + + return sp; +} + +static void target_setup_frame(int usig, struct target_sigaction *ka, + target_siginfo_t *info, target_sigset_t *set, + CPUARMState *env) +{ + struct target_rt_sigframe *frame; + abi_ulong frame_addr; + + frame_addr = get_sigframe(ka, env); + if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) { + goto give_sigsegv; + } + + __put_user(0, &frame->uc.tuc_flags); + __put_user(0, &frame->uc.tuc_link); + + __put_user(target_sigaltstack_used.ss_sp, + &frame->uc.tuc_stack.ss_sp); + __put_user(sas_ss_flags(env->xregs[31]), + &frame->uc.tuc_stack.ss_flags); + __put_user(target_sigaltstack_used.ss_size, + &frame->uc.tuc_stack.ss_size); + target_setup_sigframe(frame, env, set); + /* mov x8,#__NR_rt_sigreturn; svc #0 */ + __put_user(0xd2801168, &frame->tramp[0]); + __put_user(0xd4000001, &frame->tramp[1]); + env->xregs[0] = usig; + env->xregs[31] = frame_addr; + env->xregs[29] = env->xregs[31] + offsetof(struct target_rt_sigframe, fp); + env->pc = ka->_sa_handler; + env->xregs[30] = env->xregs[31] + + offsetof(struct target_rt_sigframe, tramp); + if (info) { + if (copy_siginfo_to_user(&frame->info, info)) { + goto give_sigsegv; + } + env->xregs[1] = frame_addr + offsetof(struct target_rt_sigframe, info); + env->xregs[2] = frame_addr + offsetof(struct target_rt_sigframe, uc); + } + + unlock_user_struct(frame, frame_addr, 1); + return; + + give_sigsegv: + unlock_user_struct(frame, frame_addr, 1); + force_sig(TARGET_SIGSEGV); +} + +static void setup_rt_frame(int sig, struct target_sigaction *ka, + target_siginfo_t *info, target_sigset_t *set, + CPUARMState *env) +{ + target_setup_frame(sig, ka, info, set, env); +} + +static void setup_frame(int sig, struct target_sigaction *ka, + target_sigset_t *set, CPUARMState *env) +{ + target_setup_frame(sig, ka, 0, set, env); +} + +long do_rt_sigreturn(CPUARMState *env) +{ + struct target_rt_sigframe *frame; + abi_ulong frame_addr = env->xregs[31]; + + if (frame_addr & 15) { + goto badframe; + } + + if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) { + goto badframe; + } + + if (target_restore_sigframe(env, frame)) { + goto badframe; + } + + if (do_sigaltstack(frame_addr + + offsetof(struct target_rt_sigframe, uc.tuc_stack), + 0, get_sp_from_cpustate(env)) == -EFAULT) { + goto badframe; + } + + unlock_user_struct(frame, frame_addr, 0); + return env->xregs[0]; + + badframe: + unlock_user_struct(frame, frame_addr, 0); + force_sig(TARGET_SIGSEGV); + return 0; +} + +long do_sigreturn(CPUARMState *env) +{ + return do_rt_sigreturn(env); +} + #elif defined(TARGET_ARM) struct target_sigcontext { -- cgit v1.2.3