[PATCH] M68k update (part 42)

M68k task and thread updates

12 files changed, 241 insertions, 116 deletions

diff --git a/arch/m68k/fpsp040/skeleton.S b/arch/m68k/fpsp040/skeleton.S
index eb1bfd1252aa..9d239b3fecc0 100644
--- a/arch/m68k/fpsp040/skeleton.S
+++ b/arch/m68k/fpsp040/skeleton.S
@@ -381,9 +381,9 @@ fpsp_done:
 .Lnotkern:
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
-	tstl	%curptr@(TASK_NEEDRESCHED)
+	tstb	%curptr@(TASK_NEEDRESCHED)
 	jne	ret_from_exception	| deliver signals,
-						| reschedule etc..
+					| reschedule etc..
 	RESTORE_ALL
 
 |
diff --git a/arch/m68k/ifpsp060/iskeleton.S b/arch/m68k/ifpsp060/iskeleton.S
index 9bcd0632cee0..3a35c413efa2 100644
--- a/arch/m68k/ifpsp060/iskeleton.S
+++ b/arch/m68k/ifpsp060/iskeleton.S
@@ -75,7 +75,7 @@ _060_isp_done:
 .Lnotkern:
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
-	tstl	%curptr@(TASK_NEEDRESCHED)
+	tstb	%curptr@(TASK_NEEDRESCHED)
 	jne	ret_from_exception	| deliver signals,
 					| reschedule etc..
 	RESTORE_ALL
diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S
index b6de3c12a283..a8f20fb5c520 100644
--- a/arch/m68k/kernel/entry.S
+++ b/arch/m68k/kernel/entry.S
@@ -68,21 +68,11 @@ ENTRY(trap)
 	addql	#4,%sp
 	jra	ret_from_exception
 
-ENTRY(reschedule)
-	| save top of frame
-	movel	%sp,%curptr@(TASK_THREAD+THREAD_ESP0)
-
-	pea	ret_from_exception
-	jmp	schedule
-
-	| After a fork we jump here directly from resume,
-	| so that %d1 contains the previous task
-	| Theoretically only needed on SMP, but let's watch
-	| what happens in schedule_tail() in future...
+	| schedule_tail is only used with CONFIG_SMP
 ENTRY(ret_from_fork)
-	movel	%d1,%sp@-
+#ifdef CONFIG_SMP
 	jsr	schedule_tail
-	addql	#4,%sp
+#endif
 	jra	ret_from_exception
 
 badsys:
@@ -128,38 +118,54 @@ ENTRY(system_call)
 	| save top of frame
 	movel	%sp,%curptr@(TASK_THREAD+THREAD_ESP0)
 
-	btst	#PT_TRACESYS_BIT,%curptr@(TASK_PTRACE+PT_TRACESYS_OFF)
+	tstb	%curptr@(TASK_SYSCALL_TRACE)
 	jne	do_trace
 	cmpl	#NR_syscalls,%d0
 	jcc	badsys
 	jbsr	@(sys_call_table,%d0:l:4)@(0)
 	movel	%d0,%sp@(PT_D0)		| save the return value
 
+	|oriw	#0x0700,%sr
+	movel	%curptr@(TASK_WORK),%d0
+	jne	syscall_exit_work
+1:	RESTORE_ALL
+
+syscall_exit_work:
+	btst	#5,%sp@(PT_SR)		| check if returning to kernel
+	bnes	1b			| if so, skip resched, signals
+	tstw	%d0
+	jeq	do_signal_return
+	tstb	%d0
+	jne	do_delayed_trace
+
+	pea	resume_userspace
+	jmp	schedule
+
 ret_from_exception:
 	btst	#5,%sp@(PT_SR)		| check if returning to kernel
-	bnes	2f			| if so, skip resched, signals
+	bnes	1f			| if so, skip resched, signals
 	| only allow interrupts when we are really the last one on the
 	| kernel stack, otherwise stack overflow can occur during
 	| heavy interrupt load
 	andw	#ALLOWINT,%sr
-	tstl	%curptr@(TASK_NEEDRESCHED)
-	jne	reschedule
-#if 0
-	cmpl	#task,%curptr		| task[0] cannot have signals
-	jeq	2f
-#endif
-					| check for delayed trace
-	bclr	#PT_DTRACE_BIT,%curptr@(TASK_PTRACE+PT_DTRACE_OFF)
-	jne	do_delayed_trace
-5:
-	tstl	%curptr@(TASK_STATE)	| state
-	jne	reschedule
 
-	tstl	%curptr@(TASK_SIGPENDING)
-	jne	Lsignal_return
-2:	RESTORE_ALL
+resume_userspace:
+	movel	%curptr@(TASK_WORK),%d0
+	lsrl	#8,%d0
+	jne	exit_work
+1:	RESTORE_ALL
+
+exit_work:
+	| save top of frame
+	movel	%sp,%curptr@(TASK_THREAD+THREAD_ESP0)
+	tstb	%d0
+	jeq	do_signal_return
+
+	pea	resume_userspace
+	jmp	schedule
 
-Lsignal_return:
+do_signal_return:
+	|andw	#ALLOWINT,%sr
 	subql	#4,%sp			| dummy return address
 	SAVE_SWITCH_STACK
 	pea	%sp@(SWITCH_STACK_SIZE)
@@ -168,7 +174,7 @@ Lsignal_return:
 	addql	#8,%sp
 	RESTORE_SWITCH_STACK
 	addql	#4,%sp
-	RESTORE_ALL
+	jbra	resume_userspace
 
 do_delayed_trace:
 	bclr	#7,%sp@(PT_SR)		| clear trace bit in SR
@@ -178,13 +184,13 @@ do_delayed_trace:
 	jbsr	send_sig
 	addql	#8,%sp
 	addql	#4,%sp
-	jra	5b
+	jbra	resume_userspace
 
 
 #if 0
 #if CONFIG_AMIGA
 ami_inthandler:
-	addql	#1,irq_stat+8		| local_irq_count
+	addql	#1,irq_stat+CPUSTAT_LOCAL_IRQ_COUNT
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
 
@@ -216,14 +222,14 @@ ENTRY(nmi_handler)
 inthandler:
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
-	addql	#1,irq_stat+8		| local_irq_count
+	addql	#1,irq_stat+CPUSTAT_LOCAL_IRQ_COUNT
 					|  put exception # in d0
 	bfextu %sp@(PT_VECTOR){#4,#10},%d0
 
 	movel	%sp,%sp@-
 	movel	%d0,%sp@- 		|  put vector # on stack
 #if defined(MACH_Q40_ONLY) && defined(CONFIG_BLK_DEV_FD)
-	btstb	#4,0xff000000	| Q40 floppy needs very special treatment ...
+	btstb	#4,0xff000000		| Q40 floppy needs very special treatment ...
 	jbeq	1f
 	btstb	#3,0xff000004		
 	jbeq	1f
@@ -231,11 +237,11 @@ inthandler:
 	jbra	3f
 1:
 #endif		
-	jbsr	process_int|  process the IRQ
+	jbsr	process_int		|  process the IRQ
 3:     	addql	#8,%sp			|  pop parameters off stack
 
 ret_from_interrupt:
-	subql	#1,irq_stat+8		| local_irq_count
+	subql	#1,irq_stat+CPUSTAT_LOCAL_IRQ_COUNT
 	jeq	1f
 2:
 	RESTORE_ALL
@@ -248,11 +254,8 @@ ret_from_interrupt:
 	jhi	2b
 #endif
 	/* check if we need to do software interrupts */
-
-	movel	irq_stat,%d0		| softirq_active
-	andl	irq_stat+4,%d0		| softirq_mask
+	tstl	irq_stat+CPUSTAT_SOFTIRQ_PENDING
 	jeq	ret_from_exception
-
 	pea	ret_from_exception
 	jra	do_softirq
 
diff --git a/arch/m68k/kernel/head.S b/arch/m68k/kernel/head.S
index 2cb593986772..bcaba1d0d973 100644
--- a/arch/m68k/kernel/head.S
+++ b/arch/m68k/kernel/head.S
@@ -1543,8 +1543,8 @@ L(cache_done):
 /*
  * Setup initial stack pointer
  */
-	lea	init_task_union,%curptr
-	lea	0x2000(%curptr),%sp
+	lea	init_task,%curptr
+	lea	init_thread_union+THREAD_SIZE,%sp
 
 	putc	'K'
 
diff --git a/arch/m68k/kernel/m68k_defs.c b/arch/m68k/kernel/m68k_defs.c
index 42873ab0e674..39e22b8cf916 100644
--- a/arch/m68k/kernel/m68k_defs.c
+++ b/arch/m68k/kernel/m68k_defs.c
@@ -25,8 +25,11 @@ int main(void)
 	DEFINE(TASK_STATE, offsetof(struct task_struct, state));
 	DEFINE(TASK_FLAGS, offsetof(struct task_struct, flags));
 	DEFINE(TASK_PTRACE, offsetof(struct task_struct, ptrace));
-#error	DEFINE(TASK_SIGPENDING, offsetof(struct task_struct, work.sigpending));
-#error	DEFINE(TASK_NEEDRESCHED, offsetof(struct task_struct, work.need_resched));
+	DEFINE(TASK_WORK, offsetof(struct task_struct, thread.work));
+	DEFINE(TASK_NEEDRESCHED, offsetof(struct task_struct, thread.work.need_resched));
+	DEFINE(TASK_SYSCALL_TRACE, offsetof(struct task_struct, thread.work.syscall_trace));
+	DEFINE(TASK_SIGPENDING, offsetof(struct task_struct, thread.work.sigpending));
+	DEFINE(TASK_NOTIFY_RESUME, offsetof(struct task_struct, thread.work.notify_resume));
 	DEFINE(TASK_THREAD, offsetof(struct task_struct, thread));
 	DEFINE(TASK_MM, offsetof(struct task_struct, mm));
 	DEFINE(TASK_ACTIVE_MM, offsetof(struct task_struct, active_mm));
@@ -66,6 +69,12 @@ int main(void)
 	/* offsets into the kernel_stat struct */
 	DEFINE(STAT_IRQ, offsetof(struct kernel_stat, irqs));
 
+	/* offsets into the irq_cpustat_t struct */
+	DEFINE(CPUSTAT_SOFTIRQ_PENDING, offsetof(irq_cpustat_t, __softirq_pending));
+	DEFINE(CPUSTAT_LOCAL_IRQ_COUNT, offsetof(irq_cpustat_t, __local_irq_count));
+	DEFINE(CPUSTAT_LOCAL_BH_COUNT, offsetof(irq_cpustat_t, __local_bh_count));
+	DEFINE(CPUSTAT_SYSCALL_COUNT, offsetof(irq_cpustat_t, __syscall_count));
+
 	/* offsets into the bi_record struct */
 	DEFINE(BIR_TAG, offsetof(struct bi_record, tag));
 	DEFINE(BIR_SIZE, offsetof(struct bi_record, size));
diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c
index 2e57f752ec98..85f6e37b693f 100644
--- a/arch/m68k/kernel/process.c
+++ b/arch/m68k/kernel/process.c
@@ -24,6 +24,7 @@
 #include <linux/user.h>
 #include <linux/a.out.h>
 #include <linux/reboot.h>
+#include <linux/init_task.h>
 
 #include <asm/uaccess.h>
 #include <asm/system.h>
@@ -33,7 +34,7 @@
 #include <asm/pgtable.h>
 
 /*
- * Initial task structure. Make this a per-architecture thing,
+ * Initial task/thread structure. Make this a per-architecture thing,
  * because different architectures tend to have different
  * alignment requirements and potentially different initial
  * setup.
@@ -43,14 +44,34 @@ static struct files_struct init_files = INIT_FILES;
 static struct signal_struct init_signals = INIT_SIGNALS;
 struct mm_struct init_mm = INIT_MM(init_mm);
 
-union task_union init_task_union
-__attribute__((section("init_task"), aligned(THREAD_SIZE)))
-	= { task: INIT_TASK(init_task_union.task) };
+union thread_union init_thread_union
+__attribute__((section(".data.init_task"), aligned(THREAD_SIZE)))
+       = { INIT_THREAD_INFO(init_task) };
+
+/* initial task structure */
+struct task_struct init_task = INIT_TASK(init_task);
+
 
 asmlinkage void ret_from_fork(void);
 
 
 /*
+ * Return saved PC from a blocked thread
+ */
+unsigned long thread_saved_pc(struct task_struct *tsk)
+{
+	extern void scheduling_functions_start_here(void);
+	extern void scheduling_functions_end_here(void);
+	struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
+	/* Check whether the thread is blocked in resume() */
+	if (sw->retpc > (unsigned long)scheduling_functions_start_here &&
+	    sw->retpc < (unsigned long)scheduling_functions_end_here)
+		return ((unsigned long *)sw->a6)[1];
+	else
+		return sw->retpc;
+}
+
+/*
  * The idle loop on an m68k..
  */
 void default_idle(void)
@@ -133,23 +154,26 @@ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 	register long retval __asm__ ("d0");
 	register long clone_arg __asm__ ("d1") = flags | CLONE_VM;
 
+	retval = __NR_clone;
 	__asm__ __volatile__
 	  ("clrl %%d2\n\t"
 	   "trap #0\n\t"		/* Linux/m68k system call */
 	   "tstl %0\n\t"		/* child or parent */
 	   "jne 1f\n\t"			/* parent - jump */
 	   "lea %%sp@(%c7),%6\n\t"	/* reload current */
+	   "movel %6@,%6\n\t"
 	   "movel %3,%%sp@-\n\t"	/* push argument */
 	   "jsr %4@\n\t"		/* call fn */
 	   "movel %0,%%d1\n\t"		/* pass exit value */
-	   "movel %2,%0\n\t"		/* exit */
+	   "movel %2,%%d0\n\t"		/* exit */
 	   "trap #0\n"
 	   "1:"
-	   : "=d" (retval)
-	   : "0" (__NR_clone), "i" (__NR_exit),
+	   : "+d" (retval)
+	   : "i" (__NR_clone), "i" (__NR_exit),
 	     "r" (arg), "a" (fn), "d" (clone_arg), "r" (current),
 	     "i" (-THREAD_SIZE)
-	   : "d0", "d2");
+	   : "d2");
+
 	pid = retval;
 	}
 
@@ -366,7 +390,7 @@ unsigned long get_wchan(struct task_struct *p)
 	if (!p || p == current || p->state == TASK_RUNNING)
 		return 0;
 
-	stack_page = (unsigned long)p;
+	stack_page = (unsigned long)(p->thread_info);
 	fp = ((struct switch_stack *)p->thread.ksp)->a6;
 	do {
 		if (fp < stack_page+sizeof(struct task_struct) ||
diff --git a/arch/m68k/kernel/ptrace.c b/arch/m68k/kernel/ptrace.c
index 61c16c6e19a1..cba62cc1c115 100644
--- a/arch/m68k/kernel/ptrace.c
+++ b/arch/m68k/kernel/ptrace.c
@@ -98,12 +98,13 @@ void ptrace_disable(struct task_struct *child)
 	/* make sure the single step bit is not set. */
 	tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
 	put_reg(child, PT_SR, tmp);
+	child->thread.work.delayed_trace = 0;
+	child->thread.work.syscall_trace = 0;
 }
 
 asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
 {
 	struct task_struct *child;
-	unsigned long flags;
 	int ret;
 
 	lock_kernel();
@@ -243,14 +244,16 @@ asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
 			ret = -EIO;
 			if ((unsigned long) data > _NSIG)
 				break;
-			if (request == PTRACE_SYSCALL)
-				child->ptrace |= PT_TRACESYS;
-			else
-				child->ptrace &= ~PT_TRACESYS;
+			if (request == PTRACE_SYSCALL) {
+					child->thread.work.syscall_trace = ~0;
+			} else {
+					child->thread.work.syscall_trace = 0;
+			}
 			child->exit_code = data;
 			/* make sure the single step bit is not set. */
 			tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
 			put_reg(child, PT_SR, tmp);
+			child->thread.work.delayed_trace = 0;
 			wake_up_process(child);
 			ret = 0;
 			break;
@@ -271,6 +274,7 @@ asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
 	/* make sure the single step bit is not set. */
 			tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
 			put_reg(child, PT_SR, tmp);
+			child->thread.work.delayed_trace = 0;
 			wake_up_process(child);
 			break;
 		}
@@ -281,9 +285,10 @@ asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
 			ret = -EIO;
 			if ((unsigned long) data > _NSIG)
 				break;
-			child->ptrace &= ~PT_TRACESYS;
+			child->thread.work.syscall_trace = 0;
 			tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16);
 			put_reg(child, PT_SR, tmp);
+			child->thread.work.delayed_trace = 1;
 
 			child->exit_code = data;
 	/* give it a chance to run. */
@@ -354,7 +359,7 @@ asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
 			break;
 	}
 out_tsk:
-	free_task_struct(child);
+	put_task_struct(child);
 out:
 	unlock_kernel();
 	return ret;
@@ -362,8 +367,8 @@ out:
 
 asmlinkage void syscall_trace(void)
 {
-	if ((current->ptrace & (PT_PTRACED|PT_TRACESYS))
-			!= (PT_PTRACED|PT_TRACESYS))
+	if (!current->thread.work.delayed_trace &&
+	    !current->thread.work.syscall_trace)
 		return;
 	current->exit_code = SIGTRAP;
 	current->state = TASK_STOPPED;
diff --git a/arch/m68k/kernel/signal.c b/arch/m68k/kernel/signal.c
index bedc542cc234..e45e7441d1a3 100644
--- a/arch/m68k/kernel/signal.c
+++ b/arch/m68k/kernel/signal.c
@@ -792,10 +792,10 @@ static void setup_frame (int sig, struct k_sigaction *ka,
 		regs->stkadj = fsize;
 	}
 
-	err |= __put_user((current->exec_domain
-			   && current->exec_domain->signal_invmap
+	err |= __put_user((current_thread_info()->exec_domain
+			   && current_thread_info()->exec_domain->signal_invmap
 			   && sig < 32
-			   ? current->exec_domain->signal_invmap[sig]
+			   ? current_thread_info()->exec_domain->signal_invmap[sig]
 			   : sig),
 			  &frame->sig);
 
@@ -870,10 +870,10 @@ static void setup_rt_frame (int sig, struct k_sigaction *ka, siginfo_t *info,
 		regs->stkadj = fsize;
 	}
 
-	err |= __put_user((current->exec_domain
-			   && current->exec_domain->signal_invmap
+	err |= __put_user((current_thread_info()->exec_domain
+			   && current_thread_info()->exec_domain->signal_invmap
 			   && sig < 32
-			   ? current->exec_domain->signal_invmap[sig]
+			   ? current_thread_info()->exec_domain->signal_invmap[sig]
 			   : sig),
 			  &frame->sig);
 	err |= __put_user(&frame->info, &frame->pinfo);
diff --git a/include/asm-m68k/entry.h b/include/asm-m68k/entry.h
index c35ec2e45aa6..ab9cd8c80af2 100644
--- a/include/asm-m68k/entry.h
+++ b/include/asm-m68k/entry.h
@@ -111,6 +111,7 @@ PT_DTRACE_BIT = 2
 	movel	%sp,\reg
 	andw	#-THREAD_SIZE,\reg
 	movel	\reg,%curptr
+	movel	%curptr@,%curptr
 .endm
 
 #else /* C source */
diff --git a/include/asm-m68k/processor.h b/include/asm-m68k/processor.h
index 7ba60318ce28..864e69653644 100644
--- a/include/asm-m68k/processor.h
+++ b/include/asm-m68k/processor.h
@@ -59,11 +59,16 @@ extern inline void wrusp(unsigned long usp) {
 #define EISA_bus 0
 #define MCA_bus 0
 
-/* 
- * if you change this structure, you must change the code and offsets
- * in m68k/machasm.S
- */
-   
+struct task_work {
+	unsigned char sigpending;
+	unsigned char notify_resume;	/* request for notification on
+					   userspace execution resumption */
+	char          need_resched;
+	unsigned char delayed_trace;	/* single step a syscall */
+	unsigned char syscall_trace;	/* count of syscall interceptors */
+	unsigned char pad[3];
+};
+
 struct thread_struct {
 	unsigned long  ksp;		/* kernel stack pointer */
 	unsigned long  usp;		/* user stack pointer */
@@ -76,11 +81,13 @@ struct thread_struct {
 	unsigned long  fp[8*3];
 	unsigned long  fpcntl[3];	/* fp control regs */
 	unsigned char  fpstate[FPSTATESIZE];  /* floating point state */
+	struct task_work work;
 };
 
-#define INIT_THREAD  { \
-	sizeof(init_stack) + (unsigned long) init_stack, 0, \
-	PS_S, __KERNEL_DS, \
+#define INIT_THREAD  {						\
+	ksp: sizeof(init_stack) + (unsigned long) init_stack,	\
+	sr: PS_S, 						\
+	fs: __KERNEL_DS,					\
 }
 
 /*
@@ -117,21 +124,7 @@ static inline void exit_thread(void)
 {
 }
 
-/*
- * Return saved PC of a blocked thread.
- */
-extern inline unsigned long thread_saved_pc(struct thread_struct *t)
-{
-	extern void scheduling_functions_start_here(void);
-	extern void scheduling_functions_end_here(void);
-	struct switch_stack *sw = (struct switch_stack *)t->ksp;
-	/* Check whether the thread is blocked in resume() */
-	if (sw->retpc > (unsigned long)scheduling_functions_start_here &&
-	    sw->retpc < (unsigned long)scheduling_functions_end_here)
-		return ((unsigned long *)sw->a6)[1];
-	else
-		return sw->retpc;
-}
+extern unsigned long thread_saved_pc(struct task_struct *tsk);
 
 unsigned long get_wchan(struct task_struct *p);
 
@@ -144,17 +137,6 @@ unsigned long get_wchan(struct task_struct *p);
 	eip; })
 #define	KSTK_ESP(tsk)	((tsk) == current ? rdusp() : (tsk)->thread.usp)
 
-#define THREAD_SIZE (2*PAGE_SIZE)
-
-/* Allocation and freeing of basic task resources. */
-#define alloc_task_struct() \
-	((struct task_struct *) __get_free_pages(GFP_KERNEL,1))
-#define free_task_struct(p)	free_pages((unsigned long)(p),1)
-#define get_task_struct(tsk)      atomic_inc(&virt_to_page(tsk)->count)
-
-#define init_task	(init_task_union.task)
-#define init_stack	(init_task_union.stack)
-
 #define cpu_relax()	do { } while (0)
 
 #endif
diff --git a/include/asm-m68k/system.h b/include/asm-m68k/system.h
index efc5ab8ff507..cead336436ca 100644
--- a/include/asm-m68k/system.h
+++ b/include/asm-m68k/system.h
@@ -7,7 +7,10 @@
 #include <asm/segment.h>
 #include <asm/entry.h>
 
-#define prepare_to_switch()	do { } while(0)
+#define prepare_arch_schedule(prev)		do { } while(0)
+#define finish_arch_schedule(prev)		do { } while(0)
+#define prepare_arch_switch(rq)			do { } while(0)
+#define finish_arch_switch(rq)			spin_unlock_irq(&(rq)->lock)
 
 /*
  * switch_to(n) should switch tasks to task ptr, first checking that
@@ -32,19 +35,16 @@
  * 02/17/96 - Jes Sorensen (jds@kom.auc.dk)
  *
  * Changed 96/09/19 by Andreas Schwab
- * pass prev in a0, next in a1, offset of tss in d1, and whether
- * the mm structures are shared in d2 (to avoid atc flushing).
+ * pass prev in a0, next in a1
  */
 asmlinkage void resume(void);
-#define switch_to(prev,next,last) { \
+#define switch_to(prev,next,last) do { \
   register void *_prev __asm__ ("a0") = (prev); \
   register void *_next __asm__ ("a1") = (next); \
-  register void *_last __asm__ ("d1"); \
   __asm__ __volatile__("jbsr resume" \
-		       : "=d" (_last) : "a" (_prev), "a" (_next) \
-		       : "d0", /* "d1", */ "d2", "d3", "d4", "d5", "a0", "a1"); \
-  (last) = _last; \
-}
+		       : : "a" (_prev), "a" (_next) \
+		       : "d0", "d1", "d2", "d3", "d4", "d5", "a0", "a1"); \
+} while (0)
 
 
 /* interrupt control.. */
diff --git a/include/asm-m68k/thread_info.h b/include/asm-m68k/thread_info.h
new file mode 100644
index 000000000000..64c9f51e0c63
--- /dev/null
+++ b/include/asm-m68k/thread_info.h
@@ -0,0 +1,101 @@
+#ifndef _ASM_M68K_THREAD_INFO_H
+#define _ASM_M68K_THREAD_INFO_H
+
+#include <asm/types.h>
+#include <asm/processor.h>
+#include <asm/page.h>
+
+struct thread_info {
+	struct task_struct	*task;		/* main task structure */
+	struct exec_domain	*exec_domain;	/* execution domain */
+	__s32			preempt_count; /* 0 => preemptable, <0 => BUG */
+	__u32 cpu; /* should always be 0 on m68k */
+
+	__u8			supervisor_stack[0];
+};
+
+#define PREEMPT_ACTIVE		0x4000000
+
+#define INIT_THREAD_INFO(tsk)			\
+{						\
+	task:		&tsk,			\
+	exec_domain:	&default_exec_domain,	\
+}
+
+/* THREAD_SIZE should be 8k, so handle differently for 4k and 8k machines */
+#if PAGE_SHIFT == 13 /* 8k machines */
+#define alloc_thread_info()   ((struct thread_info *)__get_free_pages(GFP_KERNEL,0))
+#define free_thread_info(ti)  free_pages((unsigned long)(ti),0)
+#else /* otherwise assume 4k pages */
+#define alloc_thread_info()   ((struct thread_info *)__get_free_pages(GFP_KERNEL,1))
+#define free_thread_info(ti)  free_pages((unsigned long)(ti),1)
+#endif /* PAGE_SHIFT == 13 */
+
+#define init_thread_info	(init_thread_union.thread_info)
+#define init_stack		(init_thread_union.stack)
+
+#define current_thread_info()	(current->thread_info)
+
+
+#define __HAVE_THREAD_FUNCTIONS
+
+#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
+#define TIF_DELAYED_TRACE	1	/* single step a syscall */
+#define TIF_NOTIFY_RESUME	2	/* resumption notification requested */
+#define TIF_SIGPENDING		3	/* signal pending */
+#define TIF_NEED_RESCHED	4	/* rescheduling necessary */
+
+extern int thread_flag_fixme(void);
+
+/*
+ * flag set/clear/test wrappers
+ * - pass TIF_xxxx constants to these functions
+ */
+
+#define __set_tsk_thread_flag(tsk, flag, val) ({ 	\
+	switch (flag) {					\
+	case TIF_SIGPENDING:				\
+		tsk->thread.work.sigpending = val;	\
+		break;					\
+	case TIF_NEED_RESCHED:				\
+		tsk->thread.work.need_resched = val;	\
+		break;					\
+	default:					\
+		thread_flag_fixme();			\
+	}						\
+})
+
+#define __get_tsk_thread_flag(tsk, flag) ({		\
+	int ___res;					\
+	switch (flag) {					\
+	case TIF_SIGPENDING:				\
+		___res = tsk->thread.work.sigpending;	\
+		break;					\
+	case TIF_NEED_RESCHED:				\
+		___res = tsk->thread.work.need_resched;	\
+		break;					\
+	default:					\
+		___res = thread_flag_fixme();		\
+	}						\
+	___res;						\
+})
+
+#define __get_set_tsk_thread_flag(tsk, flag, val) ({	\
+	int __res = __get_tsk_thread_flag(tsk, flag);	\
+	__set_tsk_thread_flag(tsk, flag, val);		\
+	__res;						\
+})
+
+#define set_tsk_thread_flag(tsk, flag) __set_tsk_thread_flag(tsk, flag, ~0)
+#define clear_tsk_thread_flag(tsk, flag) __set_tsk_thread_flag(tsk, flag, 0)
+#define test_and_set_tsk_thread_flag(tsk, flag) __get_set_tsk_thread_flag(tsk, flag, ~0)
+#define test_tsk_thread_flag(tsk, flag) __get_tsk_thread_flag(tsk, flag)
+
+#define set_thread_flag(flag) set_tsk_thread_flag(current, flag)
+#define clear_thread_flag(flag) clear_tsk_thread_flag(current, flag)
+#define test_thread_flag(flag) test_tsk_thread_flag(current, flag)
+
+#define set_need_resched() set_thread_flag(TIF_NEED_RESCHED)
+#define clear_need_resched() clear_thread_flag(TIF_NEED_RESCHED)
+
+#endif	/* _ASM_M68K_THREAD_INFO_H */