Pull utrace into release branch

5 files changed, 101 insertions, 52 deletions

diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index 0dd6c1419d8..7ef0c594f5e 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -534,6 +534,11 @@ GLOBAL_ENTRY(ia64_trace_syscall)
  	stf.spill [r16]=f10
  	stf.spill [r17]=f11
 	br.call.sptk.many rp=syscall_trace_enter // give parent a chance to catch syscall args
+	cmp.lt p6,p0=r8,r0			// check tracehook
+	adds r2=PT(R8)+16,sp			// r2 = &pt_regs.r8
+	adds r3=PT(R10)+16,sp			// r3 = &pt_regs.r10
+	mov r10=0
+(p6)	br.cond.sptk strace_error		// syscall failed ->
 	adds r16=PT(F6)+16,sp
 	adds r17=PT(F7)+16,sp
 	;;
diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c
index fc8f3509df2..ada4605d122 100644
--- a/arch/ia64/kernel/perfmon.c
+++ b/arch/ia64/kernel/perfmon.c
@@ -40,6 +40,7 @@
 #include <linux/capability.h>
 #include <linux/rcupdate.h>
 #include <linux/completion.h>
+#include <linux/tracehook.h>
 
 #include <asm/errno.h>
 #include <asm/intrinsics.h>
@@ -3684,7 +3685,7 @@ pfm_restart(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
 
 		PFM_SET_WORK_PENDING(task, 1);
 
-		tsk_set_notify_resume(task);
+		set_notify_resume(task);
 
 		/*
 		 * XXX: send reschedule if task runs on another CPU
@@ -5044,8 +5045,6 @@ pfm_handle_work(void)
 
 	PFM_SET_WORK_PENDING(current, 0);
 
-	tsk_clear_notify_resume(current);
-
 	regs = task_pt_regs(current);
 
 	/*
@@ -5414,7 +5413,7 @@ pfm_overflow_handler(struct task_struct *task, pfm_context_t *ctx, u64 pmc0, str
 			 * when coming from ctxsw, current still points to the
 			 * previous task, therefore we must work with task and not current.
 			 */
-			tsk_set_notify_resume(task);
+			set_notify_resume(task);
 		}
 		/*
 		 * defer until state is changed (shorten spin window). the context is locked
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index 3ab8373103e..341a0319a5b 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -28,6 +28,7 @@
 #include <linux/delay.h>
 #include <linux/kdebug.h>
 #include <linux/utsname.h>
+#include <linux/tracehook.h>
 
 #include <asm/cpu.h>
 #include <asm/delay.h>
@@ -160,21 +161,6 @@ show_regs (struct pt_regs *regs)
 		show_stack(NULL, NULL);
 }
 
-void tsk_clear_notify_resume(struct task_struct *tsk)
-{
-#ifdef CONFIG_PERFMON
-	if (tsk->thread.pfm_needs_checking)
-		return;
-#endif
-	if (test_ti_thread_flag(task_thread_info(tsk), TIF_RESTORE_RSE))
-		return;
-	clear_ti_thread_flag(task_thread_info(tsk), TIF_NOTIFY_RESUME);
-}
-
-/*
- * do_notify_resume_user():
- *	Called from notify_resume_user at entry.S, with interrupts disabled.
- */
 void
 do_notify_resume_user(sigset_t *unused, struct sigscratch *scr, long in_syscall)
 {
@@ -203,6 +189,11 @@ do_notify_resume_user(sigset_t *unused, struct sigscratch *scr, long in_syscall)
 		ia64_do_signal(scr, in_syscall);
 	}
 
+	if (test_thread_flag(TIF_NOTIFY_RESUME)) {
+		clear_thread_flag(TIF_NOTIFY_RESUME);
+		tracehook_notify_resume(&scr->pt);
+	}
+
 	/* copy user rbs to kernel rbs */
 	if (unlikely(test_thread_flag(TIF_RESTORE_RSE))) {
 		local_irq_enable();	/* force interrupt enable */
diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c
index 2a9943b5947..92c9689b7d9 100644
--- a/arch/ia64/kernel/ptrace.c
+++ b/arch/ia64/kernel/ptrace.c
@@ -22,6 +22,7 @@
 #include <linux/signal.h>
 #include <linux/regset.h>
 #include <linux/elf.h>
+#include <linux/tracehook.h>
 
 #include <asm/pgtable.h>
 #include <asm/processor.h>
@@ -603,7 +604,7 @@ void ia64_ptrace_stop(void)
 {
 	if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE))
 		return;
-	tsk_set_notify_resume(current);
+	set_notify_resume(current);
 	unw_init_running(do_sync_rbs, ia64_sync_user_rbs);
 }
 
@@ -613,7 +614,6 @@ void ia64_ptrace_stop(void)
 void ia64_sync_krbs(void)
 {
 	clear_tsk_thread_flag(current, TIF_RESTORE_RSE);
-	tsk_clear_notify_resume(current);
 
 	unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs);
 }
@@ -644,7 +644,7 @@ ptrace_attach_sync_user_rbs (struct task_struct *child)
 		spin_lock_irq(&child->sighand->siglock);
 		if (child->state == TASK_STOPPED &&
 		    !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
-			tsk_set_notify_resume(child);
+			set_notify_resume(child);
 
 			child->state = TASK_TRACED;
 			stopped = 1;
@@ -1232,37 +1232,16 @@ arch_ptrace (struct task_struct *child, long request, long addr, long data)
 }
 
 
-static void
-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;
-	}
-}
-
 /* "asmlinkage" so the input arguments are preserved... */
 
-asmlinkage void
+asmlinkage long
 syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
 		     long arg4, long arg5, long arg6, long arg7,
 		     struct pt_regs regs)
 {
-	if (test_thread_flag(TIF_SYSCALL_TRACE) 
-	    && (current->ptrace & PT_PTRACED))
-		syscall_trace();
+	if (test_thread_flag(TIF_SYSCALL_TRACE))
+		if (tracehook_report_syscall_entry(&regs))
+			return -ENOSYS;
 
 	/* copy user rbs to kernel rbs */
 	if (test_thread_flag(TIF_RESTORE_RSE))
@@ -1283,6 +1262,7 @@ syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
 		audit_syscall_entry(arch, syscall, arg0, arg1, arg2, arg3);
 	}
 
+	return 0;
 }
 
 /* "asmlinkage" so the input arguments are preserved... */
@@ -1292,6 +1272,8 @@ syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
 		     long arg4, long arg5, long arg6, long arg7,
 		     struct pt_regs regs)
 {
+	int step;
+
 	if (unlikely(current->audit_context)) {
 		int success = AUDITSC_RESULT(regs.r10);
 		long result = regs.r8;
@@ -1301,10 +1283,9 @@ syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
 		audit_syscall_exit(success, result);
 	}
 
-	if ((test_thread_flag(TIF_SYSCALL_TRACE)
-	    || test_thread_flag(TIF_SINGLESTEP))
-	    && (current->ptrace & PT_PTRACED))
-		syscall_trace();
+	step = test_thread_flag(TIF_SINGLESTEP);
+	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+		tracehook_report_syscall_exit(&regs, step);
 
 	/* copy user rbs to kernel rbs */
 	if (test_thread_flag(TIF_RESTORE_RSE))
@@ -1940,7 +1921,7 @@ gpregs_writeback(struct task_struct *target,
 {
 	if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE))
 		return 0;
-	tsk_set_notify_resume(target);
+	set_notify_resume(target);
 	return do_regset_call(do_gpregs_writeback, target, regset, 0, 0,
 		NULL, NULL);
 }
@@ -2199,3 +2180,68 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
 #endif
 	return &user_ia64_view;
 }
+
+struct syscall_get_set_args {
+	unsigned int i;
+	unsigned int n;
+	unsigned long *args;
+	struct pt_regs *regs;
+	int rw;
+};
+
+static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data)
+{
+	struct syscall_get_set_args *args = data;
+	struct pt_regs *pt = args->regs;
+	unsigned long *krbs, cfm, ndirty;
+	int i, count;
+
+	if (unw_unwind_to_user(info) < 0)
+		return;
+
+	cfm = pt->cr_ifs;
+	krbs = (unsigned long *)info->task + IA64_RBS_OFFSET/8;
+	ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
+
+	count = 0;
+	if (in_syscall(pt))
+		count = min_t(int, args->n, cfm & 0x7f);
+
+	for (i = 0; i < count; i++) {
+		if (args->rw)
+			*ia64_rse_skip_regs(krbs, ndirty + i + args->i) =
+				args->args[i];
+		else
+			args->args[i] = *ia64_rse_skip_regs(krbs,
+				ndirty + i + args->i);
+	}
+
+	if (!args->rw) {
+		while (i < args->n) {
+			args->args[i] = 0;
+			i++;
+		}
+	}
+}
+
+void ia64_syscall_get_set_arguments(struct task_struct *task,
+	struct pt_regs *regs, unsigned int i, unsigned int n,
+	unsigned long *args, int rw)
+{
+	struct syscall_get_set_args data = {
+		.i = i,
+		.n = n,
+		.args = args,
+		.regs = regs,
+		.rw = rw,
+	};
+
+	if (task == current)
+		unw_init_running(syscall_get_set_args_cb, &data);
+	else {
+		struct unw_frame_info ufi;
+		memset(&ufi, 0, sizeof(ufi));
+		unw_init_from_blocked_task(&ufi, task);
+		syscall_get_set_args_cb(&ufi, &data);
+	}
+}
diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c
index 19c5a78636f..e12500a9c44 100644
--- a/arch/ia64/kernel/signal.c
+++ b/arch/ia64/kernel/signal.c
@@ -11,6 +11,7 @@
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/ptrace.h>
+#include <linux/tracehook.h>
 #include <linux/sched.h>
 #include <linux/signal.h>
 #include <linux/smp.h>
@@ -439,6 +440,13 @@ handle_signal (unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigse
 		sigaddset(&current->blocked, sig);
 	recalc_sigpending();
 	spin_unlock_irq(&current->sighand->siglock);
+
+	/*
+	 * Let tracing know that we've done the handler setup.
+	 */
+	tracehook_signal_handler(sig, info, ka, &scr->pt,
+				 test_thread_flag(TIF_SINGLESTEP));
+
 	return 1;
 }