From e1eecd1d9d4c1ade32e0499272f04d67a8ae913d Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 9 Mar 2018 17:09:43 +0000 Subject: aarch64-linux-user: Remove struct target_aux_context MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This changes the qemu signal frame layout to be more like the kernel's, in that the various records are dynamically allocated rather than fixed in place by a structure. For now, all of the allocation is out of uc.tuc_mcontext.__reserved, so the allocation is actually trivial. That will change with SVE support. Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-id: 20180303143823.27055-4-richard.henderson@linaro.org Reviewed-by: Alex Bennée Signed-off-by: Peter Maydell --- linux-user/signal.c | 89 ++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 61 insertions(+), 28 deletions(-) (limited to 'linux-user') diff --git a/linux-user/signal.c b/linux-user/signal.c index 761d6acbf3..0f2b155c33 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -1446,20 +1446,12 @@ struct target_fpsimd_context { 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; +}; + +struct target_rt_frame_record { uint64_t fp; uint64_t lr; uint32_t tramp[2]; @@ -1565,20 +1557,47 @@ static void target_restore_fpsimd_record(CPUARMState *env, static int target_restore_sigframe(CPUARMState *env, struct target_rt_sigframe *sf) { - struct target_aux_context *aux - = (struct target_aux_context *)sf->uc.tuc_mcontext.__reserved; - uint32_t magic, size; + struct target_aarch64_ctx *ctx; + struct target_fpsimd_context *fpsimd = NULL; target_restore_general_frame(env, sf); - __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)) { - target_restore_fpsimd_record(env, &aux->fpsimd); - } else { + ctx = (struct target_aarch64_ctx *)sf->uc.tuc_mcontext.__reserved; + while (ctx) { + uint32_t magic, size; + + __get_user(magic, &ctx->magic); + __get_user(size, &ctx->size); + switch (magic) { + case 0: + if (size != 0) { + return 1; + } + ctx = NULL; + continue; + + case TARGET_FPSIMD_MAGIC: + if (fpsimd || size != sizeof(struct target_fpsimd_context)) { + return 1; + } + fpsimd = (struct target_fpsimd_context *)ctx; + break; + + default: + /* Unknown record -- we certainly didn't generate it. + * Did we in fact get out of sync? + */ + return 1; + } + ctx = (void *)ctx + size; + } + + /* Require FPSIMD always. */ + if (!fpsimd) { return 1; } + target_restore_fpsimd_record(env, fpsimd); + return 0; } @@ -1604,20 +1623,33 @@ static void target_setup_frame(int usig, struct target_sigaction *ka, target_siginfo_t *info, target_sigset_t *set, CPUARMState *env) { + int size = offsetof(struct target_rt_sigframe, uc.tuc_mcontext.__reserved); + int fpsimd_ofs, end1_ofs, fr_ofs; struct target_rt_sigframe *frame; - struct target_aux_context *aux; + struct target_rt_frame_record *fr; abi_ulong frame_addr, return_addr; + fpsimd_ofs = size; + size += sizeof(struct target_fpsimd_context); + end1_ofs = size; + size += sizeof(struct target_aarch64_ctx); + fr_ofs = size; + size += sizeof(struct target_rt_frame_record); + frame_addr = get_sigframe(ka, env); trace_user_setup_frame(env, frame_addr); if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) { goto give_sigsegv; } - aux = (struct target_aux_context *)frame->uc.tuc_mcontext.__reserved; target_setup_general_frame(frame, env, set); - target_setup_fpsimd_record(&aux->fpsimd, env); - target_setup_end_record(&aux->end); + target_setup_fpsimd_record((void *)frame + fpsimd_ofs, env); + target_setup_end_record((void *)frame + end1_ofs); + + /* Set up the stack frame for unwinding. */ + fr = (void *)frame + fr_ofs; + __put_user(env->xregs[29], &fr->fp); + __put_user(env->xregs[30], &fr->lr); if (ka->sa_flags & TARGET_SA_RESTORER) { return_addr = ka->sa_restorer; @@ -1627,13 +1659,14 @@ static void target_setup_frame(int usig, struct target_sigaction *ka, * Since these are instructions they need to be put as little-endian * regardless of target default or current CPU endianness. */ - __put_user_e(0xd2801168, &frame->tramp[0], le); - __put_user_e(0xd4000001, &frame->tramp[1], le); - return_addr = frame_addr + offsetof(struct target_rt_sigframe, tramp); + __put_user_e(0xd2801168, &fr->tramp[0], le); + __put_user_e(0xd4000001, &fr->tramp[1], le); + return_addr = frame_addr + fr_ofs + + offsetof(struct target_rt_frame_record, tramp); } env->xregs[0] = usig; env->xregs[31] = frame_addr; - env->xregs[29] = env->xregs[31] + offsetof(struct target_rt_sigframe, fp); + env->xregs[29] = frame_addr + fr_ofs; env->pc = ka->_sa_handler; env->xregs[30] = return_addr; if (info) { -- cgit v1.2.1