1 files changed, 78 insertions, 172 deletions

diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index a895e69379f..93b9ca42e5c 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -1,7 +1,7 @@
 /*
  * This file handles the architecture dependent parts of process handling.
  *
- *    Copyright IBM Corp. 1999,2009
+ *    Copyright IBM Corp. 1999, 2009
  *    Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
  *		 Hartmut Penner <hp@de.ibm.com>,
  *		 Denis Joseph Barrow,
@@ -9,42 +9,29 @@
 
 #include <linux/compiler.h>
 #include <linux/cpu.h>
-#include <linux/errno.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
-#include <linux/fs.h>
+#include <linux/elfcore.h>
 #include <linux/smp.h>
-#include <linux/stddef.h>
 #include <linux/slab.h>
-#include <linux/unistd.h>
-#include <linux/ptrace.h>
-#include <linux/vmalloc.h>
-#include <linux/user.h>
 #include <linux/interrupt.h>
-#include <linux/delay.h>
-#include <linux/reboot.h>
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/notifier.h>
 #include <linux/tick.h>
-#include <linux/elfcore.h>
-#include <linux/kernel_stat.h>
 #include <linux/personality.h>
 #include <linux/syscalls.h>
 #include <linux/compat.h>
 #include <linux/kprobes.h>
 #include <linux/random.h>
-#include <asm/compat.h>
-#include <asm/uaccess.h>
-#include <asm/pgtable.h>
-#include <asm/system.h>
+#include <linux/module.h>
 #include <asm/io.h>
 #include <asm/processor.h>
+#include <asm/vtimer.h>
+#include <asm/exec.h>
 #include <asm/irq.h>
-#include <asm/timer.h>
 #include <asm/nmi.h>
 #include <asm/smp.h>
+#include <asm/switch_to.h>
+#include <asm/runtime_instr.h>
 #include "entry.h"
 
 asmlinkage void ret_from_fork(void) asm ("ret_from_fork");
@@ -74,82 +61,38 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
 	return sf->gprs[8];
 }
 
-/*
- * The idle loop on a S390...
- */
-static void default_idle(void)
+void arch_cpu_idle(void)
 {
-	if (cpu_is_offline(smp_processor_id()))
-		cpu_die();
-	local_irq_disable();
-	if (need_resched()) {
-		local_irq_enable();
-		return;
-	}
 	local_mcck_disable();
-	if (test_thread_flag(TIF_MCCK_PENDING)) {
+	if (test_cpu_flag(CIF_MCCK_PENDING)) {
 		local_mcck_enable();
 		local_irq_enable();
-		s390_handle_mcck();
 		return;
 	}
-	trace_hardirqs_on();
-	/* Don't trace preempt off for idle. */
-	stop_critical_timings();
-	/* Stop virtual timer and halt the cpu. */
+	/* Halt the cpu and keep track of cpu time accounting. */
 	vtime_stop_cpu();
-	/* Reenable preemption tracer. */
-	start_critical_timings();
+	local_irq_enable();
 }
 
-void cpu_idle(void)
+void arch_cpu_idle_exit(void)
 {
-	for (;;) {
-		tick_nohz_stop_sched_tick(1);
-		while (!need_resched())
-			default_idle();
-		tick_nohz_restart_sched_tick();
-		preempt_enable_no_resched();
-		schedule();
-		preempt_disable();
-	}
+	if (test_cpu_flag(CIF_MCCK_PENDING))
+		s390_handle_mcck();
 }
 
-extern void __kprobes kernel_thread_starter(void);
-
-asm(
-	".section .kprobes.text, \"ax\"\n"
-	".global kernel_thread_starter\n"
-	"kernel_thread_starter:\n"
-	"    la    2,0(10)\n"
-	"    basr  14,9\n"
-	"    la    2,0\n"
-	"    br    11\n"
-	".previous\n");
-
-int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
+void arch_cpu_idle_dead(void)
 {
-	struct pt_regs regs;
-
-	memset(&regs, 0, sizeof(regs));
-	regs.psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
-	regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE;
-	regs.gprs[9] = (unsigned long) fn;
-	regs.gprs[10] = (unsigned long) arg;
-	regs.gprs[11] = (unsigned long) do_exit;
-	regs.orig_gpr2 = -1;
-
-	/* Ok, create the new process.. */
-	return do_fork(flags | CLONE_VM | CLONE_UNTRACED,
-		       0, &regs, 0, NULL, NULL);
+	cpu_die();
 }
-EXPORT_SYMBOL(kernel_thread);
+
+extern void __kprobes kernel_thread_starter(void);
 
 /*
  * Free current thread data structures etc..
  */
 void exit_thread(void)
 {
+	exit_thread_runtime_instr();
 }
 
 void flush_thread(void)
@@ -161,8 +104,7 @@ void release_thread(struct task_struct *dead_task)
 }
 
 int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
-		unsigned long unused,
-		struct task_struct *p, struct pt_regs *regs)
+		unsigned long arg, struct task_struct *p)
 {
 	struct thread_info *ti;
 	struct fake_frame
@@ -173,93 +115,82 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
 
 	frame = container_of(task_pt_regs(p), struct fake_frame, childregs);
 	p->thread.ksp = (unsigned long) frame;
-	/* Store access registers to kernel stack of new process. */
-	frame->childregs = *regs;
-	frame->childregs.gprs[2] = 0;	/* child returns 0 on fork. */
-	frame->childregs.gprs[15] = new_stackp;
-	frame->sf.back_chain = 0;
+	/* Save access registers to new thread structure. */
+	save_access_regs(&p->thread.acrs[0]);
+	/* start new process with ar4 pointing to the correct address space */
+	p->thread.mm_segment = get_fs();
+	/* Don't copy debug registers */
+	memset(&p->thread.per_user, 0, sizeof(p->thread.per_user));
+	memset(&p->thread.per_event, 0, sizeof(p->thread.per_event));
+	clear_tsk_thread_flag(p, TIF_SINGLE_STEP);
+	/* Initialize per thread user and system timer values */
+	ti = task_thread_info(p);
+	ti->user_timer = 0;
+	ti->system_timer = 0;
 
+	frame->sf.back_chain = 0;
 	/* new return point is ret_from_fork */
 	frame->sf.gprs[8] = (unsigned long) ret_from_fork;
-
 	/* fake return stack for resume(), don't go back to schedule */
 	frame->sf.gprs[9] = (unsigned long) frame;
 
-	/* Save access registers to new thread structure. */
-	save_access_regs(&p->thread.acrs[0]);
+	/* Store access registers to kernel stack of new process. */
+	if (unlikely(p->flags & PF_KTHREAD)) {
+		/* kernel thread */
+		memset(&frame->childregs, 0, sizeof(struct pt_regs));
+		frame->childregs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_DAT |
+				PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
+		frame->childregs.psw.addr = PSW_ADDR_AMODE |
+				(unsigned long) kernel_thread_starter;
+		frame->childregs.gprs[9] = new_stackp; /* function */
+		frame->childregs.gprs[10] = arg;
+		frame->childregs.gprs[11] = (unsigned long) do_exit;
+		frame->childregs.orig_gpr2 = -1;
+
+		return 0;
+	}
+	frame->childregs = *current_pt_regs();
+	frame->childregs.gprs[2] = 0;	/* child returns 0 on fork. */
+	frame->childregs.flags = 0;
+	if (new_stackp)
+		frame->childregs.gprs[15] = new_stackp;
+
+	/* Don't copy runtime instrumentation info */
+	p->thread.ri_cb = NULL;
+	p->thread.ri_signum = 0;
+	frame->childregs.psw.mask &= ~PSW_MASK_RI;
 
 #ifndef CONFIG_64BIT
 	/*
 	 * save fprs to current->thread.fp_regs to merge them with
 	 * the emulated registers and then copy the result to the child.
 	 */
-	save_fp_regs(&current->thread.fp_regs);
+	save_fp_ctl(&current->thread.fp_regs.fpc);
+	save_fp_regs(current->thread.fp_regs.fprs);
 	memcpy(&p->thread.fp_regs, &current->thread.fp_regs,
 	       sizeof(s390_fp_regs));
 	/* Set a new TLS ?  */
 	if (clone_flags & CLONE_SETTLS)
-		p->thread.acrs[0] = regs->gprs[6];
+		p->thread.acrs[0] = frame->childregs.gprs[6];
 #else /* CONFIG_64BIT */
 	/* Save the fpu registers to new thread structure. */
-	save_fp_regs(&p->thread.fp_regs);
+	save_fp_ctl(&p->thread.fp_regs.fpc);
+	save_fp_regs(p->thread.fp_regs.fprs);
+	p->thread.fp_regs.pad = 0;
 	/* Set a new TLS ?  */
 	if (clone_flags & CLONE_SETTLS) {
+		unsigned long tls = frame->childregs.gprs[6];
 		if (is_compat_task()) {
-			p->thread.acrs[0] = (unsigned int) regs->gprs[6];
+			p->thread.acrs[0] = (unsigned int)tls;
 		} else {
-			p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32);
-			p->thread.acrs[1] = (unsigned int) regs->gprs[6];
+			p->thread.acrs[0] = (unsigned int)(tls >> 32);
+			p->thread.acrs[1] = (unsigned int)tls;
 		}
 	}
 #endif /* CONFIG_64BIT */
-	/* start new process with ar4 pointing to the correct address space */
-	p->thread.mm_segment = get_fs();
-	/* Don't copy debug registers */
-	memset(&p->thread.per_user, 0, sizeof(p->thread.per_user));
-	memset(&p->thread.per_event, 0, sizeof(p->thread.per_event));
-	clear_tsk_thread_flag(p, TIF_SINGLE_STEP);
-	clear_tsk_thread_flag(p, TIF_PER_TRAP);
-	/* Initialize per thread user and system timer values */
-	ti = task_thread_info(p);
-	ti->user_timer = 0;
-	ti->system_timer = 0;
 	return 0;
 }
 
-SYSCALL_DEFINE0(fork)
-{
-	struct pt_regs *regs = task_pt_regs(current);
-	return do_fork(SIGCHLD, regs->gprs[15], regs, 0, NULL, NULL);
-}
-
-SYSCALL_DEFINE4(clone, unsigned long, newsp, unsigned long, clone_flags,
-		int __user *, parent_tidptr, int __user *, child_tidptr)
-{
-	struct pt_regs *regs = task_pt_regs(current);
-
-	if (!newsp)
-		newsp = regs->gprs[15];
-	return do_fork(clone_flags, newsp, regs, 0,
-		       parent_tidptr, child_tidptr);
-}
-
-/*
- * This is trivial, and on the face of it looks like it
- * could equally well be done in user mode.
- *
- * Not so, for quite unobvious reasons - register pressure.
- * In user mode vfork() cannot have a stack frame, and if
- * done by calling the "clone()" system call directly, you
- * do not have enough call-clobbered registers to hold all
- * the information you need.
- */
-SYSCALL_DEFINE0(vfork)
-{
-	struct pt_regs *regs = task_pt_regs(current);
-	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD,
-		       regs->gprs[15], regs, 0, NULL, NULL);
-}
-
 asmlinkage void execve_tail(void)
 {
 	current->thread.fp_regs.fpc = 0;
@@ -268,31 +199,6 @@ asmlinkage void execve_tail(void)
 }
 
 /*
- * sys_execve() executes a new program.
- */
-SYSCALL_DEFINE3(execve, const char __user *, name,
-		const char __user *const __user *, argv,
-		const char __user *const __user *, envp)
-{
-	struct pt_regs *regs = task_pt_regs(current);
-	char *filename;
-	long rc;
-
-	filename = getname(name);
-	rc = PTR_ERR(filename);
-	if (IS_ERR(filename))
-		return rc;
-	rc = do_execve(filename, argv, envp, regs);
-	if (rc)
-		goto out;
-	execve_tail();
-	rc = regs->gprs[2];
-out:
-	putname(filename);
-	return rc;
-}
-
-/*
  * fill in the FPU structure for a core dump.
  */
 int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)
@@ -302,10 +208,12 @@ int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)
 	 * save fprs to current->thread.fp_regs to merge them with
 	 * the emulated registers and then copy the result to the dump.
 	 */
-	save_fp_regs(&current->thread.fp_regs);
+	save_fp_ctl(&current->thread.fp_regs.fpc);
+	save_fp_regs(current->thread.fp_regs.fprs);
 	memcpy(fpregs, &current->thread.fp_regs, sizeof(s390_fp_regs));
 #else /* CONFIG_64BIT */
-	save_fp_regs(fpregs);
+	save_fp_ctl(&fpregs->fpc);
+	save_fp_regs(fpregs->fprs);
 #endif /* CONFIG_64BIT */
 	return 1;
 }
@@ -353,20 +261,18 @@ static inline unsigned long brk_rnd(void)
 
 unsigned long arch_randomize_brk(struct mm_struct *mm)
 {
-	unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());
+	unsigned long ret;
 
-	if (ret < mm->brk)
-		return mm->brk;
-	return ret;
+	ret = PAGE_ALIGN(mm->brk + brk_rnd());
+	return (ret > mm->brk) ? ret : mm->brk;
 }
 
 unsigned long randomize_et_dyn(unsigned long base)
 {
-	unsigned long ret = PAGE_ALIGN(base + brk_rnd());
+	unsigned long ret;
 
 	if (!(current->flags & PF_RANDOMIZE))
 		return base;
-	if (ret < base)
-		return base;
-	return ret;
+	ret = PAGE_ALIGN(base + brk_rnd());
+	return (ret > base) ? ret : base;
 }