parisc: tracehook_report_syscall

This makes parisc use the standard tracehook_report_syscall_entry
and tracehook_report_syscall_exit hooks in <linux/tracehook.h>.

To do this, we need to access current->thread.regs, and to know
whether we're entering or exiting the syscall, so add this to
syscall_trace.

Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>

2 files changed, 14 insertions, 13 deletions

diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c
index 927db3668b6f..2118ed02e886 100644
--- a/arch/parisc/kernel/ptrace.c
+++ b/arch/parisc/kernel/ptrace.c
@@ -13,6 +13,7 @@
 #include <linux/smp.h>
 #include <linux/errno.h>
 #include <linux/ptrace.h>
+#include <linux/tracehook.h>
 #include <linux/user.h>
 #include <linux/personality.h>
 #include <linux/security.h>
@@ -264,21 +265,19 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 #endif
 
 
-void syscall_trace(void)
+void syscall_trace(int why)
 {
+        struct pt_regs *regs = &current->thread.regs;
+
         if (!test_thread_flag(TIF_SYSCALL_TRACE))
                 return;
-        if (!(current->ptrace & PT_PTRACED))
-                return;
-        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
+         * Report the system call for tracing.  Entry tracing can
+         * decide to abort the call.  We handle that by setting an
+         * invalid syscall number (-1) to force an ENOSYS error.
          */
-        if (current->exit_code) {
-                send_sig(current->exit_code, current, 1);
-                current->exit_code = 0;
-        }
+        if (why)
+                tracehook_report_syscall_exit(regs, 0);
+        else if (tracehook_report_syscall_entry(regs))
+                regs->gr[20] = -1;      /* force ENOSYS */
 }
diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S
index 59fc1a43ec3e..5698668166cd 100644
--- a/arch/parisc/kernel/syscall.S
+++ b/arch/parisc/kernel/syscall.S
@@ -288,6 +288,7 @@ tracesys:
         STREG   %r18,PT_GR18(%r2)
         /* Finished saving things for the debugger */
 
+        ldi     0,%r26                          /* syscall entry */
         ldil    L%syscall_trace,%r1
         ldil    L%tracesys_next,%r2
         be      R%syscall_trace(%sr7,%r1)
@@ -336,6 +337,7 @@ tracesys_exit:
 #ifdef CONFIG_64BIT
         ldo     -16(%r30),%r29                  /* Reference param save area */
 #endif
+        ldi     1,%r26                          /* syscall exit */
         bl      syscall_trace, %r2
         STREG   %r28,TASK_PT_GR28(%r1)          /* save return value now */
         ldo     -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1      /* get task ptr */
@@ -358,7 +360,7 @@ tracesys_sigexit:
         ldo     -16(%r30),%r29                  /* Reference param save area */
 #endif
         bl      syscall_trace, %r2
-        nop
+        ldi     1,%r26                          /* syscall exit */
 
         ldil    L%syscall_exit_rfi,%r1
         be,n    R%syscall_exit_rfi(%sr7,%r1)