m68knommu: NPTL support for uClinux

Port syscalls for NPTL support to m68knommu.

Signed-off-by: Maxim Kuvyrkov <maxim@codesourcery.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

arch/m68k/include/asm/thread_info_no.h

@@ -37,6 +37,7 @@ struct thread_info {
 	unsigned long	   flags;		/* low level flags */
 	int		   cpu;			/* cpu we're on */
 	int		   preempt_count;	/* 0 => preemptable, <0 => BUG */
+	unsigned long	   tp_value;		/* thread pointer */
 	struct restart_block restart_block;
 };
 

arch/m68knommu/kernel/process.c

@@ -221,6 +221,10 @@ int copy_thread(unsigned long clone_flags,
 
 	p->thread.usp = usp;
 	p->thread.ksp = (unsigned long)childstack;
+
+	if (clone_flags & CLONE_SETTLS)
+		task_thread_info(p)->tp_value = regs->d5;
+
 	/*
 	 * Must save the current SFC/DFC value, NOT the value when
 	 * the parent was last descheduled - RGH  10-08-96

arch/m68knommu/kernel/ptrace.c

@@ -319,6 +319,11 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 		}
 #endif
 
+	case PTRACE_GET_THREAD_AREA:
+		ret = put_user(task_thread_info(child)->tp_value,
+			       (unsigned long __user *)data);
+		break;
+
 		default:
 			ret = -EIO;
 			break;

arch/m68knommu/kernel/sys_m68k.c

@@ -190,3 +190,39 @@ int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 			: "d" (__a), "d" (__b), "d" (__c));
 	return __res;
 }
+
+asmlinkage unsigned long sys_get_thread_area(void)
+{
+	return current_thread_info()->tp_value;
+}
+
+asmlinkage int sys_set_thread_area(unsigned long tp)
+{
+	current_thread_info()->tp_value = tp;
+	return 0;
+}
+
+/* This syscall gets its arguments in A0 (mem), D2 (oldval) and
+   D1 (newval).  */
+asmlinkage int
+sys_atomic_cmpxchg_32(unsigned long newval, int oldval, int d3, int d4, int d5,
+		      unsigned long __user * mem)
+{
+	struct mm_struct *mm = current->mm;
+	unsigned long mem_value;
+
+	down_read(&mm->mmap_sem);
+
+	mem_value = *mem;
+	if (mem_value == oldval)
+		*mem = newval;
+
+	up_read(&mm->mmap_sem);
+	return mem_value;
+}
+
+asmlinkage int sys_atomic_barrier(void)
+{
+	/* no code needed for uniprocs */
+	return 0;
+}

arch/m68knommu/kernel/syscalltable.S

@@ -351,6 +351,10 @@ ENTRY(sys_call_table)
 	.long sys_pwritev		/* 330 */
 	.long sys_rt_tgsigqueueinfo
 	.long sys_perf_event_open
+	.long sys_get_thread_area
+	.long sys_set_thread_area
+	.long sys_atomic_cmpxchg_32	/* 335 */
+	.long sys_atomic_barrier
 
 	.rept NR_syscalls-(.-sys_call_table)/4
 		.long sys_ni_syscall