xtensa: use generic tracehooks

Use tracehook_report_syscall_{entry,exit} instead of a local copy of it
in do_syscall_trace. Allow tracehook to cancel syscall by returning
invalid syscall number to the system_call function.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index f5ef3cc..37a2395 100644 (file)
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -1899,10 +1899,11 @@ ENTRY(system_call)
        movi    a4, do_syscall_trace_enter
        s32i    a3, a2, PT_SYSCALL
        callx4  a4
+       mov     a3, a6
 
        /* syscall = sys_call_table[syscall_nr] */
 
-       movi    a4, sys_call_table;
+       movi    a4, sys_call_table
        movi    a5, __NR_syscall_count
        movi    a6, -ENOSYS
        bgeu    a3, a5, 1f

diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c
index ae7985e..e246196 100644 (file)
--- a/arch/xtensa/kernel/ptrace.c
+++ b/arch/xtensa/kernel/ptrace.c
@@ -23,6 +23,7 @@
 #include <linux/security.h>
 #include <linux/signal.h>
 #include <linux/smp.h>
+#include <linux/tracehook.h>
 #include <linux/uaccess.h>
 
 #include <asm/coprocessor.h>
@@ -468,36 +469,21 @@ long arch_ptrace(struct task_struct *child, long request,
        return ret;
 }
 
-void do_syscall_trace(void)
-{
-       /*
-        * The 0x80 provides a way for the tracing parent to distinguish
-        * between a syscall stop and SIGTRAP delivery
-        */
-       ptrace_notify(SIGTRAP |
-                     ((current->ptrace & PT_TRACESYSGOOD) ? 0x80 : 0));
-
-       /*
-        * this isn't the same as continuing with a signal, but it will do
-        * for normal use.  strace only continues with a signal if the
-        * stopping signal is not SIGTRAP.  -brl
-        */
-       if (current->exit_code) {
-               send_sig(current->exit_code, current, 1);
-               current->exit_code = 0;
-       }
-}
-
-void do_syscall_trace_enter(struct pt_regs *regs)
+unsigned long do_syscall_trace_enter(struct pt_regs *regs)
 {
        if (test_thread_flag(TIF_SYSCALL_TRACE) &&
-           (current->ptrace & PT_PTRACED))
-               do_syscall_trace();
+           tracehook_report_syscall_entry(regs))
+               return -1;
+
+       return regs->areg[2];
 }
 
 void do_syscall_trace_leave(struct pt_regs *regs)
 {
-       if (test_thread_flag(TIF_SYSCALL_TRACE) &&
-           (current->ptrace & PT_PTRACED))
-               do_syscall_trace();
+       int step;
+
+       step = test_thread_flag(TIF_SINGLESTEP);
+
+       if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+               tracehook_report_syscall_exit(regs, step);
 }