[ipfire-2.x.git] / src / patches / suse-2.6.27.31 / patches.trace / s390-utrace-enablement.patch

Subject: Backport s390 kernel components required for utrace enablement

From: Ananth N. Mavinakayanahalli <ananth@in.ibm.com>

References: bnc#442709

Acked-by: John Jolly <jjolly@novell.com>
---
 arch/s390/Kconfig                   |    1 
 arch/s390/include/asm/ptrace.h      |    1 
 arch/s390/include/asm/syscall.h     |   80 ++++++++++++++++++++++++++++++++++++
 arch/s390/include/asm/thread_info.h |    2 
 arch/s390/kernel/entry.S            |   50 ++++++++++++++++++----
 arch/s390/kernel/entry64.S          |   42 ++++++++++++++----
 arch/s390/kernel/ptrace.c           |   75 +++++++++++++++++++++------------
 arch/s390/kernel/signal.c           |   13 +++++
 8 files changed, 216 insertions(+), 48 deletions(-)

--- a/arch/s390/include/asm/ptrace.h
+++ b/arch/s390/include/asm/ptrace.h
@@ -490,6 +490,7 @@ extern void user_disable_single_step(str
 
 #define user_mode(regs) (((regs)->psw.mask & PSW_MASK_PSTATE) != 0)
 #define instruction_pointer(regs) ((regs)->psw.addr & PSW_ADDR_INSN)
+#define user_stack_pointer(regs)((regs)->gprs[15])
 #define regs_return_value(regs)((regs)->gprs[2])
 #define profile_pc(regs) instruction_pointer(regs)
 extern void show_regs(struct pt_regs * regs);
--- /dev/null
+++ b/arch/s390/include/asm/syscall.h
@@ -0,0 +1,80 @@
+/*
+ * Access to user system call parameters and results
+ *
+ *  Copyright IBM Corp. 2008
+ *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_SYSCALL_H
+#define _ASM_SYSCALL_H	1
+
+#include <asm/ptrace.h>
+
+static inline long syscall_get_nr(struct task_struct *task,
+				  struct pt_regs *regs)
+{
+	if (regs->trap != __LC_SVC_OLD_PSW)
+		return -1;
+	return regs->gprs[2];
+}
+
+static inline void syscall_rollback(struct task_struct *task,
+				    struct pt_regs *regs)
+{
+	regs->gprs[2] = regs->orig_gpr2;
+}
+
+static inline long syscall_get_error(struct task_struct *task,
+				     struct pt_regs *regs)
+{
+	return (regs->gprs[2] >= -4096UL) ? -regs->gprs[2] : 0;
+}
+
+static inline long syscall_get_return_value(struct task_struct *task,
+					    struct pt_regs *regs)
+{
+	return regs->gprs[2];
+}
+
+static inline void syscall_set_return_value(struct task_struct *task,
+					    struct pt_regs *regs,
+					    int error, long val)
+{
+	regs->gprs[2] = error ? -error : val;
+}
+
+static inline void syscall_get_arguments(struct task_struct *task,
+					 struct pt_regs *regs,
+					 unsigned int i, unsigned int n,
+					 unsigned long *args)
+{
+	BUG_ON(i + n > 6);
+#ifdef CONFIG_COMPAT
+	if (test_tsk_thread_flag(task, TIF_31BIT)) {
+		if (i + n == 6)
+			args[--n] = (u32) regs->args[0];
+		while (n-- > 0)
+			args[n] = (u32) regs->gprs[2 + i + n];
+	}
+#endif
+	if (i + n == 6)
+		args[--n] = regs->args[0];
+	memcpy(args, &regs->gprs[2 + i], n * sizeof(args[0]));
+}
+
+static inline void syscall_set_arguments(struct task_struct *task,
+					 struct pt_regs *regs,
+					 unsigned int i, unsigned int n,
+					 const unsigned long *args)
+{
+	BUG_ON(i + n > 6);
+	if (i + n == 6)
+		regs->args[0] = args[--n];
+	memcpy(&regs->gprs[2 + i], args, n * sizeof(args[0]));
+}
+
+#endif	/* _ASM_SYSCALL_H */
--- a/arch/s390/include/asm/thread_info.h
+++ b/arch/s390/include/asm/thread_info.h
@@ -86,6 +86,7 @@ static inline struct thread_info *curren
  * thread information flags bit numbers
  */
 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
+#define TIF_NOTIFY_RESUME	1	/* callback before returning to user */
 #define TIF_SIGPENDING		2	/* signal pending */
 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
 #define TIF_RESTART_SVC		4	/* restart svc with new svc number */
@@ -101,6 +102,7 @@ static inline struct thread_info *curren
 #define TIF_FREEZE		21
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
+#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -76,6 +76,7 @@ config S390
 	select HAVE_KPROBES
 	select HAVE_KRETPROBES
 	select HAVE_KVM if 64BIT
+	select HAVE_ARCH_TRACEHOOK
 
 source "init/Kconfig"
 
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -52,9 +52,9 @@ SP_SIZE      =	STACK_FRAME_OVERHEAD + __
 STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
 STACK_SIZE  = 1 << STACK_SHIFT
 
-_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)
 
 #define BASED(name) name-system_call(%r13)
@@ -310,6 +310,8 @@ sysc_work:
 	jo	sysc_reschedule
 	tm	__TI_flags+7(%r9),_TIF_SIGPENDING
 	jnz	sysc_sigpending
+	tm	__TI_flags+7(%r9),_TIF_NOTIFY_RESUME
+	jnz	sysc_notify_resume
 	tm	__TI_flags+7(%r9),_TIF_RESTART_SVC
 	jo	sysc_restart
 	tm	__TI_flags+7(%r9),_TIF_SINGLE_STEP
@@ -345,6 +347,14 @@ sysc_sigpending:
 	j	sysc_work_loop
 
 #
+# _TIF_NOTIFY_RESUME is set, call do_notify_resume
+#
+sysc_notify_resume:
+	la	%r2,SP_PTREGS(%r15)	# load pt_regs
+	larl	%r14,sysc_work_loop
+	jg	do_notify_resume	# call do_notify_resume
+
+#
 # _TIF_RESTART_SVC is set, set up registers and restart svc
 #
 sysc_restart:
@@ -367,20 +377,19 @@ sysc_singlestep:
 	jg	do_single_step		# branch to do_sigtrap
 
 #
-# call syscall_trace before and after system call
-# special linkage: %r12 contains the return address for trace_svc
+# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
+# and after the system call
 #
 sysc_tracesys:
 	la	%r2,SP_PTREGS(%r15)	# load pt_regs
 	la	%r3,0
 	srl	%r7,2
 	stg	%r7,SP_R2(%r15)
-	brasl	%r14,syscall_trace
+	brasl	%r14,do_syscall_trace_enter
 	lghi	%r0,NR_syscalls
-	clg	%r0,SP_R2(%r15)
+	clgr	%r0,%r2
 	jnh	sysc_tracenogo
-	lg	%r7,SP_R2(%r15)		# strace might have changed the
-	sll	%r7,2			# system call
+	slag	%r7,%r2,2		# *4
 	lgf	%r8,0(%r7,%r10)
 sysc_tracego:
 	lmg	%r3,%r6,SP_R3(%r15)
@@ -391,9 +400,8 @@ sysc_tracenogo:
 	tm	__TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
 	jz	sysc_return
 	la	%r2,SP_PTREGS(%r15)	# load pt_regs
-	la	%r3,1
 	larl	%r14,sysc_return	# return point is sysc_return
-	jg	syscall_trace
+	jg	do_syscall_trace_exit
 
 #
 # a new process exits the kernel with ret_from_fork
@@ -672,6 +680,8 @@ io_work_loop:
 	jo	io_reschedule
 	tm	__TI_flags+7(%r9),_TIF_SIGPENDING
 	jnz	io_sigpending
+	tm	__TI_flags+7(%r9),_TIF_NOTIFY_RESUME
+	jnz	io_notify_resume
 	j	io_restore
 io_work_done:
 
@@ -712,6 +722,18 @@ io_sigpending:
 	TRACE_IRQS_OFF
 	j	io_work_loop
 
+#
+# _TIF_NOTIFY_RESUME or is set, call do_notify_resume
+#
+io_notify_resume:
+	TRACE_IRQS_ON
+	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
+	la	%r2,SP_PTREGS(%r15)	# load pt_regs
+	brasl	%r14,do_notify_resume	# call do_notify_resume
+	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
+	TRACE_IRQS_OFF
+	j	io_work_loop
+
 /*
  * External interrupt handler routine
  */
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -49,9 +49,9 @@ SP_ILC	     =	STACK_FRAME_OVERHEAD + __P
 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
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -35,6 +35,7 @@
 #include <linux/signal.h>
 #include <linux/elf.h>
 #include <linux/regset.h>
+#include <linux/tracehook.h>
 
 #include <asm/segment.h>
 #include <asm/page.h>
@@ -639,40 +640,58 @@ long compat_arch_ptrace(struct task_stru
 }
 #endif
 
-asmlinkage void
-syscall_trace(struct pt_regs *regs, int entryexit)
+asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 {
-	if (unlikely(current->audit_context) && entryexit)
-		audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]), regs->gprs[2]);
-
-	if (!test_thread_flag(TIF_SYSCALL_TRACE))
-		goto out;
-	if (!(current->ptrace & PT_PTRACED))
-		goto out;
-	ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
-				 ? 0x80 : 0));
+	long ret;
 
 	/*
-	 * If the debuffer has set an invalid system call number,
-	 * we prepare to skip the system call restart handling.
+	 * The sysc_tracesys code in entry.S stored the system
+	 * call number to gprs[2].
 	 */
-	if (!entryexit && regs->gprs[2] >= NR_syscalls)
+
+	if (is_self_ptracing(regs->gprs[2])) {
+		struct siginfo info;
+
+		memset(&info, 0, sizeof(struct siginfo));
+		info.si_signo = SIGSYS;
+		info.si_code = SYS_SYSCALL;
+		info.si_errno = regs->gprs[2];
+		info.si_addr = (void *)regs->orig_gpr2;
+		send_sig_info(SIGSYS, &info, current);
+		regs->gprs[2] = -1;
+		return -1L;
+	}
+
+	ret = regs->gprs[2];
+	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+		(tracehook_report_syscall_entry(regs) ||
+		 regs->gprs[2] >= NR_syscalls)) {
+		/*
+		 * Tracing decided this syscall should not happen or the
+		 * debugger stored an invalid system call number. Skip
+		 * the system call and the system call restart handling.
+		 */
 		regs->trap = -1;
+		ret = -1;
+	}
 
-	/*
-	 * 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;
-	}
- out:
-	if (unlikely(current->audit_context) && !entryexit)
-		audit_syscall_entry(test_thread_flag(TIF_31BIT)?AUDIT_ARCH_S390:AUDIT_ARCH_S390X,
-				    regs->gprs[2], regs->orig_gpr2, regs->gprs[3],
-				    regs->gprs[4], regs->gprs[5]);
+	if (unlikely(current->audit_context))
+		audit_syscall_entry(test_thread_flag(TIF_31BIT) ?
+				AUDIT_ARCH_S390 : AUDIT_ARCH_S390X,
+			regs->gprs[2], regs->orig_gpr2,
+			regs->gprs[3], regs->gprs[4],
+			regs->gprs[5]);
+	return ret;
+}
+
+asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
+{
+	if (unlikely(current->audit_context))
+		audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]),
+				regs->gprs[2]);
+
+	if (test_thread_flag(TIF_SYSCALL_TRACE))
+		tracehook_report_syscall_exit(regs, 0);
 }
 
 /*
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -25,6 +25,7 @@
 #include <linux/personality.h>
 #include <linux/binfmts.h>
 #include <linux/syscalls.h>
+#include <linux/tracehook.h>
 #include <asm/ucontext.h>
 #include <asm/uaccess.h>
 #include <asm/lowcore.h>
@@ -504,6 +505,12 @@ void do_signal(struct pt_regs *regs)
 			 */
 			if (current->thread.per_info.single_step)
 				set_thread_flag(TIF_SINGLE_STEP);
+
+			/*
+			 * Let tracing know that we've done the handler setup.
+			 */
+			tracehook_signal_handler(signr, &info, &ka, regs,
+					 test_thread_flag(TIF_SINGLE_STEP));
 		}
 		return;
 	}
@@ -523,3 +530,9 @@ void do_signal(struct pt_regs *regs)
 		set_thread_flag(TIF_RESTART_SVC);
 	}
 }
+
+void do_notify_resume(struct pt_regs *regs)
+{
+	clear_thread_flag(TIF_NOTIFY_RESUME);
+	tracehook_notify_resume(regs);
+}
Commit	Line	Data
00e5a55c BS	1	Subject: Backport s390 kernel components required for utrace enablement
	2
	3	From: Ananth N. Mavinakayanahalli <ananth@in.ibm.com>
	4
	5	References: bnc#442709
	6
	7	Acked-by: John Jolly <jjolly@novell.com>
	8	---
	9	arch/s390/Kconfig \| 1
	10	arch/s390/include/asm/ptrace.h \| 1
	11	arch/s390/include/asm/syscall.h \| 80 ++++++++++++++++++++++++++++++++++++
	12	arch/s390/include/asm/thread_info.h \| 2
	13	arch/s390/kernel/entry.S \| 50 ++++++++++++++++++----
	14	arch/s390/kernel/entry64.S \| 42 ++++++++++++++----
	15	arch/s390/kernel/ptrace.c \| 75 +++++++++++++++++++++------------
	16	arch/s390/kernel/signal.c \| 13 +++++
	17	8 files changed, 216 insertions(+), 48 deletions(-)
	18
	19	--- a/arch/s390/include/asm/ptrace.h
	20	+++ b/arch/s390/include/asm/ptrace.h
	21	@@ -490,6 +490,7 @@ extern void user_disable_single_step(str
	22
	23	#define user_mode(regs) (((regs)->psw.mask & PSW_MASK_PSTATE) != 0)
	24	#define instruction_pointer(regs) ((regs)->psw.addr & PSW_ADDR_INSN)
	25	+#define user_stack_pointer(regs)((regs)->gprs[15])
	26	#define regs_return_value(regs)((regs)->gprs[2])
	27	#define profile_pc(regs) instruction_pointer(regs)
	28	extern void show_regs(struct pt_regs * regs);
	29	--- /dev/null
	30	+++ b/arch/s390/include/asm/syscall.h
	31	@@ -0,0 +1,80 @@
	32	+/*
	33	+ * Access to user system call parameters and results
	34	+ *
	35	+ * Copyright IBM Corp. 2008
	36	+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
	37	+ *
	38	+ * This program is free software; you can redistribute it and/or modify
	39	+ * it under the terms of the GNU General Public License (version 2 only)
	40	+ * as published by the Free Software Foundation.
	41	+ */
	42	+
	43	+#ifndef _ASM_SYSCALL_H
	44	+#define _ASM_SYSCALL_H 1
	45	+
	46	+#include <asm/ptrace.h>
	47	+
	48	+static inline long syscall_get_nr(struct task_struct *task,
	49	+ struct pt_regs *regs)
	50	+{
	51	+ if (regs->trap != __LC_SVC_OLD_PSW)
	52	+ return -1;
	53	+ return regs->gprs[2];
	54	+}
	55	+
	56	+static inline void syscall_rollback(struct task_struct *task,
	57	+ struct pt_regs *regs)
	58	+{
	59	+ regs->gprs[2] = regs->orig_gpr2;
	60	+}
	61	+
	62	+static inline long syscall_get_error(struct task_struct *task,
	63	+ struct pt_regs *regs)
	64	+{
65	+ return (regs->gprs[2] >= -4096UL) ? -regs->gprs[2] : 0;
66	+}
67	+
68	+static inline long syscall_get_return_value(struct task_struct *task,
69	+ struct pt_regs *regs)
70	+{
71	+ return regs->gprs[2];
72	+}
73	+
74	+static inline void syscall_set_return_value(struct task_struct *task,
75	+ struct pt_regs *regs,
76	+ int error, long val)
77	+{
78	+ regs->gprs[2] = error ? -error : val;
79	+}
80	+
81	+static inline void syscall_get_arguments(struct task_struct *task,
82	+ struct pt_regs *regs,
83	+ unsigned int i, unsigned int n,
84	+ unsigned long *args)
85	+{
86	+ BUG_ON(i + n > 6);
87	+#ifdef CONFIG_COMPAT
88	+ if (test_tsk_thread_flag(task, TIF_31BIT)) {
89	+ if (i + n == 6)
90	+ args[--n] = (u32) regs->args[0];
91	+ while (n-- > 0)
92	+ args[n] = (u32) regs->gprs[2 + i + n];
93	+ }
94	+#endif
95	+ if (i + n == 6)
96	+ args[--n] = regs->args[0];
97	+ memcpy(args, &regs->gprs[2 + i], n * sizeof(args[0]));
98	+}
99	+
100	+static inline void syscall_set_arguments(struct task_struct *task,
101	+ struct pt_regs *regs,
102	+ unsigned int i, unsigned int n,
103	+ const unsigned long *args)
104	+{
105	+ BUG_ON(i + n > 6);
106	+ if (i + n == 6)
107	+ regs->args[0] = args[--n];
108	+ memcpy(&regs->gprs[2 + i], args, n * sizeof(args[0]));
109	+}
110	+
111	+#endif /* _ASM_SYSCALL_H */
112	--- a/arch/s390/include/asm/thread_info.h
113	+++ b/arch/s390/include/asm/thread_info.h
114	@@ -86,6 +86,7 @@ static inline struct thread_info *curren
115	* thread information flags bit numbers
116	*/
117	#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
118	+#define TIF_NOTIFY_RESUME 1 /* callback before returning to user */
119	#define TIF_SIGPENDING 2 /* signal pending */
120	#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
121	#define TIF_RESTART_SVC 4 /* restart svc with new svc number */
122	@@ -101,6 +102,7 @@ static inline struct thread_info *curren
123	#define TIF_FREEZE 21
124
125	#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
126	+#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
127	#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
128	#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
129	#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
130	--- a/arch/s390/Kconfig
131	+++ b/arch/s390/Kconfig
132	@@ -76,6 +76,7 @@ config S390
133	select HAVE_KPROBES
134	select HAVE_KRETPROBES
135	select HAVE_KVM if 64BIT
136	+ select HAVE_ARCH_TRACEHOOK
137
138	source "init/Kconfig"
139
140	--- a/arch/s390/kernel/entry64.S
141	+++ b/arch/s390/kernel/entry64.S
142	@@ -52,9 +52,9 @@ SP_SIZE = STACK_FRAME_OVERHEAD + __
143	STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
144	STACK_SIZE = 1 << STACK_SHIFT
145
146	-_TIF_WORK_SVC = (_TIF_SIGPENDING \| _TIF_NEED_RESCHED \| \
147	+_TIF_WORK_SVC = (_TIF_SIGPENDING \| _TIF_NOTIFY_RESUME \| _TIF_NEED_RESCHED \| \
148	_TIF_MCCK_PENDING \| _TIF_RESTART_SVC \| _TIF_SINGLE_STEP )
149	-_TIF_WORK_INT = (_TIF_SIGPENDING \| _TIF_NEED_RESCHED \| \
150	+_TIF_WORK_INT = (_TIF_SIGPENDING \| _TIF_NOTIFY_RESUME \| _TIF_NEED_RESCHED \| \
151	_TIF_MCCK_PENDING)
152
153	#define BASED(name) name-system_call(%r13)
154	@@ -310,6 +310,8 @@ sysc_work:
155	jo sysc_reschedule
156	tm __TI_flags+7(%r9),_TIF_SIGPENDING
157	jnz sysc_sigpending
158	+ tm __TI_flags+7(%r9),_TIF_NOTIFY_RESUME
159	+ jnz sysc_notify_resume
160	tm __TI_flags+7(%r9),_TIF_RESTART_SVC
161	jo sysc_restart
162	tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
163	@@ -345,6 +347,14 @@ sysc_sigpending:
164	j sysc_work_loop
165
166	#
167	+# _TIF_NOTIFY_RESUME is set, call do_notify_resume
168	+#
169	+sysc_notify_resume:
170	+ la %r2,SP_PTREGS(%r15) # load pt_regs
171	+ larl %r14,sysc_work_loop
172	+ jg do_notify_resume # call do_notify_resume
173	+
174	+#
175	# _TIF_RESTART_SVC is set, set up registers and restart svc
176	#
177	sysc_restart:
178	@@ -367,20 +377,19 @@ sysc_singlestep:
179	jg do_single_step # branch to do_sigtrap
180
181	#
182	-# call syscall_trace before and after system call
183	-# special linkage: %r12 contains the return address for trace_svc
184	+# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
185	+# and after the system call
186	#
187	sysc_tracesys:
188	la %r2,SP_PTREGS(%r15) # load pt_regs
189	la %r3,0
190	srl %r7,2
191	stg %r7,SP_R2(%r15)
192	- brasl %r14,syscall_trace
193	+ brasl %r14,do_syscall_trace_enter
194	lghi %r0,NR_syscalls
195	- clg %r0,SP_R2(%r15)
196	+ clgr %r0,%r2
197	jnh sysc_tracenogo
198	- lg %r7,SP_R2(%r15) # strace might have changed the
199	- sll %r7,2 # system call
200	+ slag %r7,%r2,2 # *4
201	lgf %r8,0(%r7,%r10)
202	sysc_tracego:
203	lmg %r3,%r6,SP_R3(%r15)
204	@@ -391,9 +400,8 @@ sysc_tracenogo:
205	tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE\|_TIF_SYSCALL_AUDIT)
206	jz sysc_return
207	la %r2,SP_PTREGS(%r15) # load pt_regs
208	- la %r3,1
209	larl %r14,sysc_return # return point is sysc_return
210	- jg syscall_trace
211	+ jg do_syscall_trace_exit
212
213	#
214	# a new process exits the kernel with ret_from_fork
215	@@ -672,6 +680,8 @@ io_work_loop:
216	jo io_reschedule
217	tm __TI_flags+7(%r9),_TIF_SIGPENDING
218	jnz io_sigpending
219	+ tm __TI_flags+7(%r9),_TIF_NOTIFY_RESUME
220	+ jnz io_notify_resume
221	j io_restore
222	io_work_done:
223
224	@@ -712,6 +722,18 @@ io_sigpending:
225	TRACE_IRQS_OFF
226	j io_work_loop
227
228	+#
229	+# _TIF_NOTIFY_RESUME or is set, call do_notify_resume
230	+#
231	+io_notify_resume:
232	+ TRACE_IRQS_ON
233	+ stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
234	+ la %r2,SP_PTREGS(%r15) # load pt_regs
235	+ brasl %r14,do_notify_resume # call do_notify_resume
236	+ stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
237	+ TRACE_IRQS_OFF
238	+ j io_work_loop
239	+
240	/*
241	* External interrupt handler routine
242	*/
243	--- a/arch/s390/kernel/entry.S
244	+++ b/arch/s390/kernel/entry.S
245	@@ -49,9 +49,9 @@ SP_ILC = STACK_FRAME_OVERHEAD + __P
246	SP_TRAP = STACK_FRAME_OVERHEAD + __PT_TRAP
247	SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE
248
249	-_TIF_WORK_SVC = (_TIF_SIGPENDING \| _TIF_NEED_RESCHED \| \
250	+_TIF_WORK_SVC = (_TIF_SIGPENDING \| _TIF_NOTIFY_RESUME \| _TIF_NEED_RESCHED \| \
251	_TIF_MCCK_PENDING \| _TIF_RESTART_SVC \| _TIF_SINGLE_STEP )
252	-_TIF_WORK_INT = (_TIF_SIGPENDING \| _TIF_NEED_RESCHED \| \
253	+_TIF_WORK_INT = (_TIF_SIGPENDING \| _TIF_NOTIFY_RESUME \| _TIF_NEED_RESCHED \| \
254	_TIF_MCCK_PENDING)
255
256	STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
257	@@ -318,6 +318,8 @@ sysc_work:
258	bo BASED(sysc_reschedule)
259	tm __TI_flags+3(%r9),_TIF_SIGPENDING
260	bnz BASED(sysc_sigpending)
261	+ tm __TI_flags+3(%r9),_TIF_NOTIFY_RESUME
262	+ bnz BASED(sysc_notify_resume)
263	tm __TI_flags+3(%r9),_TIF_RESTART_SVC
264	bo BASED(sysc_restart)
265	tm __TI_flags+3(%r9),_TIF_SINGLE_STEP
266	@@ -356,6 +358,16 @@ sysc_sigpending:
267	b BASED(sysc_work_loop)
268
269	#
270	+# _TIF_NOTIFY_RESUME is set, call do_notify_resume
271	+#
272	+sysc_notify_resume:
273	+ la %r2,SP_PTREGS(%r15) # load pt_regs
274	+ l %r1,BASED(.Ldo_notify_resume)
275	+ la %r14,BASED(sysc_work_loop)
276	+ br %r1 # call do_notify_resume
277	+
278	+
279	+#
280	# _TIF_RESTART_SVC is set, set up registers and restart svc
281	#
282	sysc_restart:
283	@@ -378,20 +390,21 @@ sysc_singlestep:
284	br %r1 # branch to do_single_step
285
286	#
287	-# call trace before and after sys_call
288	+# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
289	+# and after the system call
290	#
291	sysc_tracesys:
292	- l %r1,BASED(.Ltrace)
293	+ l %r1,BASED(.Ltrace_entry)
294	la %r2,SP_PTREGS(%r15) # load pt_regs
295	la %r3,0
296	srl %r7,2
297	st %r7,SP_R2(%r15)
298	basr %r14,%r1
299	- clc SP_R2(4,%r15),BASED(.Lnr_syscalls)
300	+ cl %r2,BASED(.Lnr_syscalls)
301	bnl BASED(sysc_tracenogo)
302	l %r8,BASED(.Lsysc_table)
303	- l %r7,SP_R2(%r15) # strace might have changed the
304	- sll %r7,2 # system call
305	+ lr %r7,%r2
306	+ sll %r7,2 # *4
307	l %r8,0(%r7,%r8)
308	sysc_tracego:
309	lm %r3,%r6,SP_R3(%r15)
310	@@ -401,9 +414,8 @@ sysc_tracego:
311	sysc_tracenogo:
312	tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE\|_TIF_SYSCALL_AUDIT)
313	bz BASED(sysc_return)
314	- l %r1,BASED(.Ltrace)
315	+ l %r1,BASED(.Ltrace_exit)
316	la %r2,SP_PTREGS(%r15) # load pt_regs
317	- la %r3,1
318	la %r14,BASED(sysc_return)
319	br %r1
320
321	@@ -666,6 +678,8 @@ io_work_loop:
322	bo BASED(io_reschedule)
323	tm __TI_flags+3(%r9),_TIF_SIGPENDING
324	bnz BASED(io_sigpending)
325	+ tm __TI_flags+3(%r9),_TIF_NOTIFY_RESUME
326	+ bnz BASED(io_notify_resume)
327	b BASED(io_restore)
328	io_work_done:
329
330	@@ -704,6 +718,19 @@ io_sigpending:
331	TRACE_IRQS_OFF
332	b BASED(io_work_loop)
333
334	+#
335	+# _TIF_SIGPENDING is set, call do_signal
336	+#
337	+io_notify_resume:
338	+ TRACE_IRQS_ON
339	+ stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
340	+ la %r2,SP_PTREGS(%r15) # load pt_regs
341	+ l %r1,BASED(.Ldo_notify_resume)
342	+ basr %r14,%r1 # call do_signal
343	+ stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
344	+ TRACE_IRQS_OFF
345	+ b BASED(io_work_loop)
346	+
347	/*
348	* External interrupt handler routine
349	*/
350	@@ -1070,6 +1097,8 @@ cleanup_io_leave_insn:
351	.Ldo_IRQ: .long do_IRQ
352	.Ldo_extint: .long do_extint
353	.Ldo_signal: .long do_signal
354	+.Ldo_notify_resume:
355	+ .long do_notify_resume
356	.Lhandle_per: .long do_single_step
357	.Ldo_execve: .long do_execve
358	.Lexecve_tail: .long execve_tail
359	@@ -1079,7 +1108,8 @@ cleanup_io_leave_insn:
360	.Lpreempt_schedule_irq:
361	.long preempt_schedule_irq
362	#endif
363	-.Ltrace: .long syscall_trace
364	+.Ltrace_entry: .long do_syscall_trace_enter
365	+.Ltrace_exit: .long do_syscall_trace_exit
366	.Lschedtail: .long schedule_tail
367	.Lsysc_table: .long sys_call_table
368	#ifdef CONFIG_TRACE_IRQFLAGS
369	--- a/arch/s390/kernel/ptrace.c
370	+++ b/arch/s390/kernel/ptrace.c
371	@@ -35,6 +35,7 @@
372	#include <linux/signal.h>
373	#include <linux/elf.h>
374	#include <linux/regset.h>
375	+#include <linux/tracehook.h>
376
377	#include <asm/segment.h>
378	#include <asm/page.h>
379	@@ -639,40 +640,58 @@ long compat_arch_ptrace(struct task_stru
380	}
381	#endif
382
383	-asmlinkage void
384	-syscall_trace(struct pt_regs *regs, int entryexit)
385	+asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
386	{
387	- if (unlikely(current->audit_context) && entryexit)
388	- audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]), regs->gprs[2]);
389	-
390	- if (!test_thread_flag(TIF_SYSCALL_TRACE))
391	- goto out;
392	- if (!(current->ptrace & PT_PTRACED))
393	- goto out;
394	- ptrace_notify(SIGTRAP \| ((current->ptrace & PT_TRACESYSGOOD)
395	- ? 0x80 : 0));
396	+ long ret;
397
398	/*
399	- * If the debuffer has set an invalid system call number,
400	- * we prepare to skip the system call restart handling.
401	+ * The sysc_tracesys code in entry.S stored the system
402	+ * call number to gprs[2].
403	*/
404	- if (!entryexit && regs->gprs[2] >= NR_syscalls)
405	+
406	+ if (is_self_ptracing(regs->gprs[2])) {
407	+ struct siginfo info;
408	+
409	+ memset(&info, 0, sizeof(struct siginfo));
410	+ info.si_signo = SIGSYS;
411	+ info.si_code = SYS_SYSCALL;
412	+ info.si_errno = regs->gprs[2];
413	+ info.si_addr = (void *)regs->orig_gpr2;
414	+ send_sig_info(SIGSYS, &info, current);
415	+ regs->gprs[2] = -1;
416	+ return -1L;
417	+ }
418	+
419	+ ret = regs->gprs[2];
420	+ if (test_thread_flag(TIF_SYSCALL_TRACE) &&
421	+ (tracehook_report_syscall_entry(regs) \|\|
422	+ regs->gprs[2] >= NR_syscalls)) {
423	+ /*
424	+ * Tracing decided this syscall should not happen or the
425	+ * debugger stored an invalid system call number. Skip
426	+ * the system call and the system call restart handling.
427	+ */
428	regs->trap = -1;
429	+ ret = -1;
430	+ }
431
432	- /*
433	- * this isn't the same as continuing with a signal, but it will do
434	- * for normal use. strace only continues with a signal if the
435	- * stopping signal is not SIGTRAP. -brl
436	- */
437	- if (current->exit_code) {
438	- send_sig(current->exit_code, current, 1);
439	- current->exit_code = 0;
440	- }
441	- out:
442	- if (unlikely(current->audit_context) && !entryexit)
443	- audit_syscall_entry(test_thread_flag(TIF_31BIT)?AUDIT_ARCH_S390:AUDIT_ARCH_S390X,
444	- regs->gprs[2], regs->orig_gpr2, regs->gprs[3],
445	- regs->gprs[4], regs->gprs[5]);
446	+ if (unlikely(current->audit_context))
447	+ audit_syscall_entry(test_thread_flag(TIF_31BIT) ?
448	+ AUDIT_ARCH_S390 : AUDIT_ARCH_S390X,
449	+ regs->gprs[2], regs->orig_gpr2,
450	+ regs->gprs[3], regs->gprs[4],
451	+ regs->gprs[5]);
452	+ return ret;
453	+}
454	+
455	+asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
456	+{
457	+ if (unlikely(current->audit_context))
458	+ audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]),
459	+ regs->gprs[2]);
460	+
461	+ if (test_thread_flag(TIF_SYSCALL_TRACE))
462	+ tracehook_report_syscall_exit(regs, 0);
463	}
464
465	/*
466	--- a/arch/s390/kernel/signal.c
467	+++ b/arch/s390/kernel/signal.c
468	@@ -25,6 +25,7 @@
469	#include <linux/personality.h>
470	#include <linux/binfmts.h>
471	#include <linux/syscalls.h>
472	+#include <linux/tracehook.h>
473	#include <asm/ucontext.h>
474	#include <asm/uaccess.h>
475	#include <asm/lowcore.h>
476	@@ -504,6 +505,12 @@ void do_signal(struct pt_regs *regs)
477	*/
478	if (current->thread.per_info.single_step)
479	set_thread_flag(TIF_SINGLE_STEP);
480	+
481	+ /*
482	+ * Let tracing know that we've done the handler setup.
483	+ */
484	+ tracehook_signal_handler(signr, &info, &ka, regs,
485	+ test_thread_flag(TIF_SINGLE_STEP));
486	}
487	return;
488	}
489	@@ -523,3 +530,9 @@ void do_signal(struct pt_regs *regs)
490	set_thread_flag(TIF_RESTART_SVC);
491	}
492	}
493	+
494	+void do_notify_resume(struct pt_regs *regs)
495	+{
496	+ clear_thread_flag(TIF_NOTIFY_RESUME);
497	+ tracehook_notify_resume(regs);
498	+}