On Tue, Oct 19, 2021 at 11:45 AM Warner Losh <imp@bsdimp.com> wrote:
>
> Implement the system call dispatch. This implements all three kinds of
> system call: direct and the two indirect variants. It handles all the
> special cases for thumb as well.
>
> Signed-off-by: Stacey Son <sson@FreeBSD.org>
> Signed-off-by: Klye Evans <kevans@FreeBSD.org>
> Signed-off-by: Warner Losh <imp@bsdimp.com>
s/Klye/Kyle/
I'll fix the typo in the QEMU.SOB file I have... <blush>
Thanks!
> ---
> bsd-user/arm/target_arch_cpu.h | 95 ++++++++++++++++++++++++++++++++++
> 1 file changed, 95 insertions(+)
>
> diff --git a/bsd-user/arm/target_arch_cpu.h b/bsd-user/arm/target_arch_cpu.h
> index 62d6ee89b6..bc2eb05cfe 100644
> --- a/bsd-user/arm/target_arch_cpu.h
> +++ b/bsd-user/arm/target_arch_cpu.h
> @@ -39,6 +39,7 @@ static inline void target_cpu_loop(CPUARMState *env)
> {
> int trapnr;
> target_siginfo_t info;
> + unsigned int n;
> CPUState *cs = env_cpu(env);
>
> for (;;) {
> @@ -57,6 +58,100 @@ static inline void target_cpu_loop(CPUARMState *env)
> queue_signal(env, info.si_signo, &info);
> }
> break;
> + case EXCP_SWI:
> + case EXCP_BKPT:
> + {
> + env->eabi = 1; /* FreeBSD is eabi only now */
> + /*
> + * system call
> + * See arm/arm/trap.c cpu_fetch_syscall_args()
> + */
> + if (trapnr == EXCP_BKPT) {
> + if (env->thumb) {
> + env->regs[15] += 2;
> + } else {
> + env->regs[15] += 4;
> + }
> + }
> + n = env->regs[7];
> + if (bsd_type == target_freebsd) {
> + int ret;
> + abi_ulong params = get_sp_from_cpustate(env);
> + int32_t syscall_nr = n;
> + int32_t arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8;
> +
> + /* See arm/arm/trap.c cpu_fetch_syscall_args() */
> + if (syscall_nr == TARGET_FREEBSD_NR_syscall) {
> + syscall_nr = env->regs[0];
> + arg1 = env->regs[1];
> + arg2 = env->regs[2];
> + arg3 = env->regs[3];
> + get_user_s32(arg4, params);
> + params += sizeof(int32_t);
> + get_user_s32(arg5, params);
> + params += sizeof(int32_t);
> + get_user_s32(arg6, params);
> + params += sizeof(int32_t);
> + get_user_s32(arg7, params);
> + arg8 = 0;
> + } else if (syscall_nr == TARGET_FREEBSD_NR___syscall) {
> + syscall_nr = env->regs[0];
> + arg1 = env->regs[2];
> + arg2 = env->regs[3];
> + get_user_s32(arg3, params);
> + params += sizeof(int32_t);
> + get_user_s32(arg4, params);
> + params += sizeof(int32_t);
> + get_user_s32(arg5, params);
> + params += sizeof(int32_t);
> + get_user_s32(arg6, params);
> + arg7 = 0;
> + arg8 = 0;
> + } else {
> + arg1 = env->regs[0];
> + arg2 = env->regs[1];
> + arg3 = env->regs[2];
> + arg4 = env->regs[3];
> + get_user_s32(arg5, params);
> + params += sizeof(int32_t);
> + get_user_s32(arg6, params);
> + params += sizeof(int32_t);
> + get_user_s32(arg7, params);
> + params += sizeof(int32_t);
> + get_user_s32(arg8, params);
> + }
> + ret = do_freebsd_syscall(env, syscall_nr, arg1, arg2, arg3,
> + arg4, arg5, arg6, arg7, arg8);
> + /*
> + * Compare to arm/arm/vm_machdep.c
> + * cpu_set_syscall_retval()
> + */
> + if (-TARGET_EJUSTRETURN == ret) {
> + /*
> + * Returning from a successful sigreturn syscall.
> + * Avoid clobbering register state.
> + */
> + break;
> + }
> + if (-TARGET_ERESTART == ret) {
> + env->regs[15] -= env->thumb ? 2 : 4;
> + break;
> + }
> + if ((unsigned int)ret >= (unsigned int)(-515)) {
> + ret = -ret;
> + cpsr_write(env, CPSR_C, CPSR_C, CPSRWriteByInstr);
> + env->regs[0] = ret;
> + } else {
> + cpsr_write(env, 0, CPSR_C, CPSRWriteByInstr);
> + env->regs[0] = ret; /* XXX need to handle lseek()? */
> + /* env->regs[1] = 0; */
> + }
> + } else {
> + fprintf(stderr, "qemu: bsd_type (= %d) syscall "
> + "not supported\n", bsd_type);
> + }
> + }
> + break;
> case EXCP_INTERRUPT:
> /* just indicate that signals should be handled asap */
> break;
> --
> 2.32.0
>
Modulo typo:
Reviewed-by: Kyle Evans <kevans@FreeBSD.org>