From 4208ccbe79fd8e0ec189a25823cc3bdbe848155d Mon Sep 17 00:00:00 2001 From: kib Date: Sun, 23 May 2010 18:32:02 +0000 Subject: Reorganize syscall entry and leave handling. Extend struct sysvec with three new elements: sv_fetch_syscall_args - the method to fetch syscall arguments from usermode into struct syscall_args. The structure is machine-depended (this might be reconsidered after all architectures are converted). sv_set_syscall_retval - the method to set a return value for usermode from the syscall. It is a generalization of cpu_set_syscall_retval(9) to allow ABIs to override the way to set a return value. sv_syscallnames - the table of syscall names. Use sv_set_syscall_retval in kern_sigsuspend() instead of hardcoding the call to cpu_set_syscall_retval(). The new functions syscallenter(9) and syscallret(9) are provided that use sv_*syscall* pointers and contain the common repeated code from the syscall() implementations for the architecture-specific syscall trap handlers. Syscallenter() fetches arguments, calls syscall implementation from ABI sysent table, and set up return frame. The end of syscall bookkeeping is done by syscallret(). Take advantage of single place for MI syscall handling code and implement ptrace_lwpinfo pl_flags PL_FLAG_SCE, PL_FLAG_SCX and PL_FLAG_EXEC. The SCE and SCX flags notify the debugger that the thread is stopped at syscall entry or return point respectively. The EXEC flag augments SCX and notifies debugger that the process address space was changed by one of exec(2)-family syscalls. The i386, amd64, sparc64, sun4v, powerpc and ia64 syscall()s are changed to use syscallenter()/syscallret(). MIPS and arm are not converted and use the mostly unchanged syscall() implementation. Reviewed by: jhb, marcel, marius, nwhitehorn, stas Tested by: marcel (ia64), marius (sparc64), nwhitehorn (powerpc), stas (mips) MFC after: 1 month --- sys/i386/linux/linux_sysvec.c | 54 ++++++++++++++++++++++++++++--------------- 1 file changed, 36 insertions(+), 18 deletions(-) (limited to 'sys/i386/linux/linux_sysvec.c') diff --git a/sys/i386/linux/linux_sysvec.c b/sys/i386/linux/linux_sysvec.c index 3f0c6f4..364cc0c 100644 --- a/sys/i386/linux/linux_sysvec.c +++ b/sys/i386/linux/linux_sysvec.c @@ -102,8 +102,6 @@ static int linux_fixup(register_t **stack_base, struct image_params *iparams); static int elf_linux_fixup(register_t **stack_base, struct image_params *iparams); -static void linux_prepsyscall(struct trapframe *tf, int *args, u_int *code, - caddr_t *params); static void linux_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask); static void exec_linux_setregs(struct thread *td, struct image_params *imgp, u_long stack); @@ -864,19 +862,33 @@ linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) return (EJUSTRETURN); } -/* - * MPSAFE - */ -static void -linux_prepsyscall(struct trapframe *tf, int *args, u_int *code, caddr_t *params) +static int +linux_fetch_syscall_args(struct thread *td, struct syscall_args *sa) { - args[0] = tf->tf_ebx; - args[1] = tf->tf_ecx; - args[2] = tf->tf_edx; - args[3] = tf->tf_esi; - args[4] = tf->tf_edi; - args[5] = tf->tf_ebp; /* Unconfirmed */ - *params = NULL; /* no copyin */ + struct proc *p; + struct trapframe *frame; + + p = td->td_proc; + frame = td->td_frame; + + sa->code = frame->tf_eax; + sa->args[0] = frame->tf_ebx; + sa->args[1] = frame->tf_ecx; + sa->args[2] = frame->tf_edx; + sa->args[3] = frame->tf_esi; + sa->args[4] = frame->tf_edi; + sa->args[5] = frame->tf_ebp; /* Unconfirmed */ + + if (sa->code >= p->p_sysent->sv_size) + sa->callp = &p->p_sysent->sv_table[0]; + else + sa->callp = &p->p_sysent->sv_table[sa->code]; + sa->narg = sa->callp->sy_narg; + + td->td_retval[0] = 0; + td->td_retval[1] = frame->tf_edx; + + return (0); } /* @@ -972,7 +984,7 @@ struct sysentvec linux_sysvec = { .sv_sendsig = linux_sendsig, .sv_sigcode = linux_sigcode, .sv_szsigcode = &linux_szsigcode, - .sv_prepsyscall = linux_prepsyscall, + .sv_prepsyscall = NULL, .sv_name = "Linux a.out", .sv_coredump = NULL, .sv_imgact_try = exec_linux_imgact_try, @@ -987,7 +999,10 @@ struct sysentvec linux_sysvec = { .sv_setregs = exec_linux_setregs, .sv_fixlimit = NULL, .sv_maxssiz = NULL, - .sv_flags = SV_ABI_LINUX | SV_AOUT | SV_IA32 | SV_ILP32 + .sv_flags = SV_ABI_LINUX | SV_AOUT | SV_IA32 | SV_ILP32, + .sv_set_syscall_retval = cpu_set_syscall_retval, + .sv_fetch_syscall_args = linux_fetch_syscall_args, + .sv_syscallnames = NULL, }; struct sysentvec elf_linux_sysvec = { @@ -1003,7 +1018,7 @@ struct sysentvec elf_linux_sysvec = { .sv_sendsig = linux_sendsig, .sv_sigcode = linux_sigcode, .sv_szsigcode = &linux_szsigcode, - .sv_prepsyscall = linux_prepsyscall, + .sv_prepsyscall = NULL, .sv_name = "Linux ELF", .sv_coredump = elf32_coredump, .sv_imgact_try = exec_linux_imgact_try, @@ -1018,7 +1033,10 @@ struct sysentvec elf_linux_sysvec = { .sv_setregs = exec_linux_setregs, .sv_fixlimit = NULL, .sv_maxssiz = NULL, - .sv_flags = SV_ABI_LINUX | SV_IA32 | SV_ILP32 + .sv_flags = SV_ABI_LINUX | SV_IA32 | SV_ILP32, + .sv_set_syscall_retval = cpu_set_syscall_retval, + .sv_fetch_syscall_args = linux_fetch_syscall_args, + .sv_syscallnames = NULL, }; static char GNU_ABI_VENDOR[] = "GNU"; -- cgit v1.1