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>

2 files changed, 14 insertions, 27 deletions

diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index f5ef3cc0497c..37a239556889 100644
--- 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 ae7985ec7b8e..e2461968efb2 100644
--- 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);
 }