m68k: Add NPTL support

This patch adds several syscalls, that provide necessary
functionality to support NPTL on m68k/ColdFire.
The syscalls are get_thread_area, set_thread_area, atomic_cmpxchg_32 and
atomic_barrier.
The cmpxchg syscall is required for ColdFire as it doesn't support 'cas'
instruction.

Also a ptrace call PTRACE_GET_THREAD_AREA is added to allow debugger to
inspect the TLS storage.

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

3 files changed, 8 insertions, 1 deletions

diff --git a/arch/m68k/include/asm/ptrace.h b/arch/m68k/include/asm/ptrace.h
index ee4011c23281..21605c736f69 100644
--- a/arch/m68k/include/asm/ptrace.h
+++ b/arch/m68k/include/asm/ptrace.h
@@ -71,6 +71,8 @@ struct switch_stack {
 #define PTRACE_GETFPREGS          14
 #define PTRACE_SETFPREGS          15
 
+#define PTRACE_GET_THREAD_AREA    25
+
 #define PTRACE_SINGLEBLOCK      33      /* resume execution until next branch */
 
 #ifdef __KERNEL__
diff --git a/arch/m68k/include/asm/thread_info_mm.h b/arch/m68k/include/asm/thread_info_mm.h
index 167e518db41b..67266c683453 100644
--- a/arch/m68k/include/asm/thread_info_mm.h
+++ b/arch/m68k/include/asm/thread_info_mm.h
@@ -16,6 +16,7 @@ struct thread_info {
         struct exec_domain      *exec_domain;   /* execution domain */
         int                     preempt_count;  /* 0 => preemptable, <0 => BUG */
         __u32 cpu; /* should always be 0 on m68k */
+        unsigned long           tp_value;       /* thread pointer */
         struct restart_block    restart_block;
 };
 #endif /* __ASSEMBLY__ */
diff --git a/arch/m68k/include/asm/unistd.h b/arch/m68k/include/asm/unistd.h
index 48b87f5ced50..d72a71dabecb 100644
--- a/arch/m68k/include/asm/unistd.h
+++ b/arch/m68k/include/asm/unistd.h
@@ -336,10 +336,14 @@
 #define __NR_pwritev            330
 #define __NR_rt_tgsigqueueinfo  331
 #define __NR_perf_event_open    332
+#define __NR_get_thread_area    333
+#define __NR_set_thread_area    334
+#define __NR_atomic_cmpxchg_32  335
+#define __NR_atomic_barrier     336
 
 #ifdef __KERNEL__
 
-#define NR_syscalls             333
+#define NR_syscalls             337
 
 #define __ARCH_WANT_IPC_PARSE_VERSION
 #define __ARCH_WANT_OLD_READDIR