[S390] ptrace changes

* System call parameter and result access functions
* Add tracehook calls
* Split syscall_trace into two functions do_syscall_trace_enter and
  do_syscall_trace_exit

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 40 insertions, 10 deletions

diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 708cf9cf9a35..ed500ef799b7 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -49,9 +49,9 @@ SP_ILC	     =	STACK_FRAME_OVERHEAD + __PT_ILC
 SP_TRAP      =  STACK_FRAME_OVERHEAD + __PT_TRAP
 SP_SIZE      =  STACK_FRAME_OVERHEAD + __PT_SIZE
 
-_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
                  _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
-_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
                  _TIF_MCCK_PENDING)
 
 STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
@@ -318,6 +318,8 @@ sysc_work:
         bo      BASED(sysc_reschedule)
         tm      __TI_flags+3(%r9),_TIF_SIGPENDING
         bnz     BASED(sysc_sigpending)
+        tm      __TI_flags+3(%r9),_TIF_NOTIFY_RESUME
+        bnz     BASED(sysc_notify_resume)
         tm      __TI_flags+3(%r9),_TIF_RESTART_SVC
         bo      BASED(sysc_restart)
         tm      __TI_flags+3(%r9),_TIF_SINGLE_STEP
@@ -356,6 +358,16 @@ sysc_sigpending:
         b       BASED(sysc_work_loop)
 
 #
+# _TIF_NOTIFY_RESUME is set, call do_notify_resume
+#
+sysc_notify_resume:
+        la      %r2,SP_PTREGS(%r15)     # load pt_regs
+        l       %r1,BASED(.Ldo_notify_resume)
+        la      %r14,BASED(sysc_work_loop)
+        br      %r1                     # call do_notify_resume
+
+
+#
 # _TIF_RESTART_SVC is set, set up registers and restart svc
 #
 sysc_restart:
@@ -378,20 +390,21 @@ sysc_singlestep:
         br      %r1                     # branch to do_single_step
 
 #
-# call trace before and after sys_call
+# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
+# and after the system call
 #
 sysc_tracesys:
-        l       %r1,BASED(.Ltrace)
+        l       %r1,BASED(.Ltrace_entry)
         la      %r2,SP_PTREGS(%r15)     # load pt_regs
         la      %r3,0
         srl     %r7,2
         st      %r7,SP_R2(%r15)
         basr    %r14,%r1
-        clc     SP_R2(4,%r15),BASED(.Lnr_syscalls)
+        cl      %r2,BASED(.Lnr_syscalls)
         bnl     BASED(sysc_tracenogo)
         l       %r8,BASED(.Lsysc_table)
-        l       %r7,SP_R2(%r15)         # strace might have changed the
-        sll     %r7,2                   #  system call
+        lr      %r7,%r2
+        sll     %r7,2                   # *4
         l       %r8,0(%r7,%r8)
 sysc_tracego:
         lm      %r3,%r6,SP_R3(%r15)
@@ -401,9 +414,8 @@ sysc_tracego:
 sysc_tracenogo:
         tm      __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
         bz      BASED(sysc_return)
-        l       %r1,BASED(.Ltrace)
+        l       %r1,BASED(.Ltrace_exit)
         la      %r2,SP_PTREGS(%r15)     # load pt_regs
-        la      %r3,1
         la      %r14,BASED(sysc_return)
         br      %r1
 
@@ -666,6 +678,8 @@ io_work_loop:
         bo      BASED(io_reschedule)
         tm      __TI_flags+3(%r9),_TIF_SIGPENDING
         bnz     BASED(io_sigpending)
+        tm      __TI_flags+3(%r9),_TIF_NOTIFY_RESUME
+        bnz     BASED(io_notify_resume)
         b       BASED(io_restore)
 io_work_done:
 
@@ -704,6 +718,19 @@ io_sigpending:
         TRACE_IRQS_OFF
         b       BASED(io_work_loop)
 
+#
+# _TIF_SIGPENDING is set, call do_signal
+#
+io_notify_resume:
+        TRACE_IRQS_ON
+        stosm   __SF_EMPTY(%r15),0x03   # reenable interrupts
+        la      %r2,SP_PTREGS(%r15)     # load pt_regs
+        l       %r1,BASED(.Ldo_notify_resume)
+        basr    %r14,%r1                # call do_signal
+        stnsm   __SF_EMPTY(%r15),0xfc   # disable I/O and ext. interrupts
+        TRACE_IRQS_OFF
+        b       BASED(io_work_loop)
+
 /*
  * External interrupt handler routine
  */
@@ -1070,6 +1097,8 @@ cleanup_io_leave_insn:
 .Ldo_IRQ:       .long   do_IRQ
 .Ldo_extint:    .long   do_extint
 .Ldo_signal:    .long   do_signal
+.Ldo_notify_resume:
+                .long   do_notify_resume
 .Lhandle_per:   .long   do_single_step
 .Ldo_execve:    .long   do_execve
 .Lexecve_tail:  .long   execve_tail
@@ -1079,7 +1108,8 @@ cleanup_io_leave_insn:
 .Lpreempt_schedule_irq:
                 .long   preempt_schedule_irq
 #endif
-.Ltrace:        .long   syscall_trace
+.Ltrace_entry:  .long   do_syscall_trace_enter
+.Ltrace_exit:   .long   do_syscall_trace_exit
 .Lschedtail:    .long   schedule_tail
 .Lsysc_table:   .long   sys_call_table
 #ifdef CONFIG_TRACE_IRQFLAGS