uml: throw out CONFIG_MODE_TT

This patchset throws out tt mode, which has been non-functional for a while.

This is done in phases, interspersed with code cleanups on the affected files.

The removal is done as follows:
	remove all code, config options, and files which depend on
CONFIG_MODE_TT
	get rid of the CHOOSE_MODE macro, which decided whether to
call tt-mode or skas-mode code, and replace invocations with their
skas portions
	replace all now-trivial procedures with their skas equivalents

There are now a bunch of now-redundant pieces of data structures, including
mode-specific pieces of the thread structure, pt_regs, and mm_context.  These
are all replaced with their skas-specific contents.

As part of the ongoing style compliance project, I made a style pass over all
files that were changed.  There are three such patches, one for each phase,
covering the files affected by that phase but no later ones.

I noticed that we weren't freeing the LDT state associated with a process when
it exited, so that's fixed in one of the later patches.

The last patch is a tidying patch which I've had for a while, but which caused
inexplicable crashes under tt mode.  Since that is no longer a problem, this
can now go in.

This patch:

Start getting rid of tt mode support.

This patch throws out CONFIG_MODE_TT and all config options, code, and files
which depend on it.

CONFIG_MODE_SKAS is gone and everything that depends on it is included
unconditionally.

The few changed lines are in re-written Kconfig help, lines which needed
something skas-related removed from them, and a few more which weren't
strictly deletions.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

21 files changed, 1 insertions, 344 deletions

diff --git a/arch/um/include/as-layout.h b/arch/um/include/as-layout.h
index fccf187bf4e..e44f32940f8 100644
--- a/arch/um/include/as-layout.h
+++ b/arch/um/include/as-layout.h
@@ -28,7 +28,6 @@ extern unsigned long _unprotected_end;
 extern unsigned long brk_start;
 
 extern int linux_main(int argc, char **argv);
-extern void set_cmdline(char *cmd);
 
 extern void (*sig_info[])(int, union uml_pt_regs *);
 
diff --git a/arch/um/include/choose-mode.h b/arch/um/include/choose-mode.h
index b87b36a87d9..51a387626da 100644
--- a/arch/um/include/choose-mode.h
+++ b/arch/um/include/choose-mode.h
@@ -8,26 +8,8 @@
 
 #include "uml-config.h"
 
-#if defined(UML_CONFIG_MODE_TT) && defined(UML_CONFIG_MODE_SKAS)
-#define CHOOSE_MODE(tt, skas) (mode_tt ? (tt) : (skas))
-
-extern int mode_tt;
-static inline void *__choose_mode(void *tt, void *skas) {
-	return mode_tt ? tt : skas;
-}
-
-#define __CHOOSE_MODE(tt, skas) (*( (typeof(tt) *) __choose_mode(&(tt), &(skas))))
-
-#elif defined(UML_CONFIG_MODE_SKAS)
 #define CHOOSE_MODE(tt, skas) (skas)
 
-#elif defined(UML_CONFIG_MODE_TT)
-#define CHOOSE_MODE(tt, skas) (tt)
-
-#else
-#error CONFIG_MODE_SKAS and CONFIG_MODE_TT are both disabled
-#endif
-
 #define CHOOSE_MODE_PROC(tt, skas, args...) \
 	CHOOSE_MODE(tt(args), skas(args))
 
diff --git a/arch/um/include/common-offsets.h b/arch/um/include/common-offsets.h
index 2378ff42e41..439b91f141a 100644
--- a/arch/um/include/common-offsets.h
+++ b/arch/um/include/common-offsets.h
@@ -1,9 +1,6 @@
 /* for use by sys-$SUBARCH/kernel-offsets.c */
 
 DEFINE(KERNEL_MADV_REMOVE, MADV_REMOVE);
-#ifdef CONFIG_MODE_TT
-OFFSET(HOST_TASK_EXTERN_PID, task_struct, thread.mode.tt.extern_pid);
-#endif
 
 OFFSET(HOST_TASK_REGS, task_struct, thread.regs);
 OFFSET(HOST_TASK_PID, task_struct, pid);
diff --git a/arch/um/include/irq_user.h b/arch/um/include/irq_user.h
index 15d311b9be9..741cb7d6f85 100644
--- a/arch/um/include/irq_user.h
+++ b/arch/um/include/irq_user.h
@@ -30,8 +30,4 @@ extern void deactivate_fd(int fd, int irqnum);
 extern int deactivate_all_fds(void);
 extern int activate_ipi(int fd, int pid);
 
-#ifdef CONFIG_MODE_TT
-extern void forward_interrupts(int pid);
-#endif
-
 #endif
diff --git a/arch/um/include/kern_util.h b/arch/um/include/kern_util.h
index b84b5dadb95..578156db303 100644
--- a/arch/um/include/kern_util.h
+++ b/arch/um/include/kern_util.h
@@ -34,9 +34,6 @@ extern int nsyscalls;
 	UML_ROUND_DOWN(((unsigned long) addr) + PAGE_SIZE - 1)
 
 extern int kernel_fork(unsigned long flags, int (*fn)(void *), void * arg);
-#ifdef UML_CONFIG_MODE_TT
-extern unsigned long stack_sp(unsigned long page);
-#endif
 extern int kernel_thread_proc(void *data);
 extern void syscall_segv(int sig);
 extern int current_pid(void);
@@ -82,9 +79,6 @@ extern void check_stack_overflow(void *ptr);
 extern void relay_signal(int sig, union uml_pt_regs *regs);
 extern int user_context(unsigned long sp);
 extern void timer_irq(union uml_pt_regs *regs);
-#ifdef CONFIG_MODE_TT
-extern void unprotect_stack(unsigned long stack);
-#endif
 extern void do_uml_exitcalls(void);
 extern int attach_debugger(int idle_pid, int pid, int stop);
 extern int config_gdb(char *str);
diff --git a/arch/um/include/mode.h b/arch/um/include/mode.h
index 786cf563eb0..fcce95cbc16 100644
--- a/arch/um/include/mode.h
+++ b/arch/um/include/mode.h
@@ -6,25 +6,6 @@
 #ifndef __MODE_H__
 #define __MODE_H__
 
-#include "uml-config.h"
-
-#ifdef UML_CONFIG_MODE_TT
-#include "mode-tt.h"
-#endif
-
-#ifdef UML_CONFIG_MODE_SKAS
 #include "mode-skas.h"
-#endif
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/include/mode_kern.h b/arch/um/include/mode_kern.h
index 88e5e77bf51..b2a44c0dcd0 100644
--- a/arch/um/include/mode_kern.h
+++ b/arch/um/include/mode_kern.h
@@ -6,12 +6,6 @@
 #ifndef __MODE_KERN_H__
 #define __MODE_KERN_H__
 
-#ifdef CONFIG_MODE_TT
-#include "mode_kern_tt.h"
-#endif
-
-#ifdef CONFIG_MODE_SKAS
 #include "mode_kern_skas.h"
-#endif
 
 #endif
diff --git a/arch/um/include/os.h b/arch/um/include/os.h
index c0803e67fc6..208d9b91fc9 100644
--- a/arch/um/include/os.h
+++ b/arch/um/include/os.h
@@ -178,11 +178,7 @@ extern void check_host_supports_tls(int *supports_tls, int *tls_min);
 
 /* Make sure they are clear when running in TT mode. Required by
  * SEGV_MAYBE_FIXABLE */
-#ifdef UML_CONFIG_MODE_SKAS
 #define clear_can_do_skas() do { ptrace_faultinfo = proc_mm = 0; } while (0)
-#else
-#define clear_can_do_skas() do {} while (0)
-#endif
 
 /* mem.c */
 extern int create_mem_file(unsigned long long len);
@@ -193,18 +189,11 @@ extern int os_process_parent(int pid);
 extern void os_stop_process(int pid);
 extern void os_kill_process(int pid, int reap_child);
 extern void os_kill_ptraced_process(int pid, int reap_child);
-#ifdef UML_CONFIG_MODE_TT
-extern void os_usr1_process(int pid);
-#endif
 extern long os_ptrace_ldt(long pid, long addr, long data);
 
 extern int os_getpid(void);
 extern int os_getpgrp(void);
 
-#ifdef UML_CONFIG_MODE_TT
-extern void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int));
-extern void stop(void);
-#endif
 extern void init_new_thread_signals(void);
 extern int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr);
 
@@ -217,18 +206,6 @@ extern int os_drop_memory(void *addr, int length);
 extern int can_drop_memory(void);
 extern void os_flush_stdout(void);
 
-/* tt.c
- * for tt mode only (will be deleted in future...)
- */
-extern void forward_ipi(int fd, int pid);
-extern void kill_child_dead(int pid);
-extern int wait_for_stop(int pid, int sig, int cont_type, void *relay);
-extern int protect_memory(unsigned long addr, unsigned long len,
-			  int r, int w, int x, int must_succeed);
-extern void forward_pending_sigio(int target);
-extern int start_fork_tramp(void *arg, unsigned long temp_stack,
-			    int clone_flags, int (*tramp)(void *));
-
 /* uaccess.c */
 extern unsigned long __do_user_copy(void *to, const void *from, int n,
 				    void **fault_addr, void **fault_catcher,
@@ -281,9 +258,6 @@ extern void os_dump_core(void);
 extern void switch_timers(int to_real);
 extern void idle_sleep(int secs);
 extern int set_interval(int is_virtual);
-#ifdef CONFIG_MODE_TT
-extern void enable_timer(void);
-#endif
 extern void disable_timer(void);
 extern void uml_idle_timer(void);
 extern unsigned long long os_nsecs(void);
diff --git a/arch/um/include/sysdep-i386/ptrace.h b/arch/um/include/sysdep-i386/ptrace.h
index b45a72feb08..c0ea4dbd042 100644
--- a/arch/um/include/sysdep-i386/ptrace.h
+++ b/arch/um/include/sysdep-i386/ptrace.h
@@ -14,12 +14,7 @@
 #define MAX_REG_NR (UM_FRAME_SIZE / sizeof(unsigned long))
 #define MAX_REG_OFFSET (UM_FRAME_SIZE)
 
-#ifdef UML_CONFIG_PT_PROXY
-extern void update_debugregs(int seq);
-#else
 static inline void update_debugregs(int seq) {}
-#endif
-
 
 /* syscall emulation path in ptrace */
 
@@ -31,12 +26,6 @@ void set_using_sysemu(int value);
 int get_using_sysemu(void);
 extern int sysemu_supported;
 
-#ifdef UML_CONFIG_MODE_TT
-#include "sysdep/sc.h"
-#endif
-
-#ifdef UML_CONFIG_MODE_SKAS
-
 #include "skas_ptregs.h"
 
 #define REGS_IP(r) ((r)[HOST_IP])
@@ -60,20 +49,11 @@ extern int sysemu_supported;
 
 #define REGS_RESTART_SYSCALL(r) IP_RESTART_SYSCALL(REGS_IP(r))
 
-#endif
 #ifndef PTRACE_SYSEMU_SINGLESTEP
 #define PTRACE_SYSEMU_SINGLESTEP 32
 #endif
 
 union uml_pt_regs {
-#ifdef UML_CONFIG_MODE_TT
-	struct tt_regs {
-		long syscall;
-		void *sc;
-                struct faultinfo faultinfo;
-	} tt;
-#endif
-#ifdef UML_CONFIG_MODE_SKAS
 	struct skas_regs {
 		unsigned long regs[MAX_REG_NR];
 		unsigned long fp[HOST_FP_SIZE];
@@ -82,13 +62,10 @@ union uml_pt_regs {
 		long syscall;
 		int is_user;
 	} skas;
-#endif
 };
 
 #define EMPTY_UML_PT_REGS { }
 
-extern int mode_tt;
-
 #define UPT_SC(r) ((r)->tt.sc)
 #define UPT_IP(r) \
 	__CHOOSE_MODE(SC_IP(UPT_SC(r)), REGS_IP((r)->skas.regs))
diff --git a/arch/um/include/sysdep-i386/sigcontext.h b/arch/um/include/sysdep-i386/sigcontext.h
index 23fd2644d7e..8658634ca4f 100644
--- a/arch/um/include/sysdep-i386/sigcontext.h
+++ b/arch/um/include/sysdep-i386/sigcontext.h
@@ -30,11 +30,7 @@
 #define SEGV_IS_FIXABLE(fi)	((fi)->trap_no == 14)
 
 /* SKAS3 has no trap_no on i386, but get_skas_faultinfo() sets it to 0. */
-#ifdef UML_CONFIG_MODE_SKAS
 #define SEGV_MAYBE_FIXABLE(fi)	((fi)->trap_no == 0 && ptrace_faultinfo)
-#else
-#define SEGV_MAYBE_FIXABLE(fi)	0
-#endif
 
 extern unsigned long *sc_sigmask(void *sc_ptr);
 extern int sc_get_fpregs(unsigned long buf, void *sc_ptr);
diff --git a/arch/um/include/sysdep-i386/thread.h b/arch/um/include/sysdep-i386/thread.h
index 243fed44d78..0cf7bf6e9e0 100644
--- a/arch/um/include/sysdep-i386/thread.h
+++ b/arch/um/include/sysdep-i386/thread.h
@@ -4,8 +4,5 @@
 #include <kern_constants.h>
 
 #define TASK_DEBUGREGS(task) ((unsigned long *) &(((char *) (task))[HOST_TASK_DEBUGREGS]))
-#ifdef UML_CONFIG_MODE_TT
-#define TASK_EXTERN_PID(task) *((int *) &(((char *) (task))[HOST_TASK_EXTERN_PID]))
-#endif
 
 #endif
diff --git a/arch/um/include/sysdep-x86_64/ptrace.h b/arch/um/include/sysdep-x86_64/ptrace.h
index 62403bd9966..ff525bda4c1 100644
--- a/arch/um/include/sysdep-x86_64/ptrace.h
+++ b/arch/um/include/sysdep-x86_64/ptrace.h
@@ -1,5 +1,6 @@
 /*
  * Copyright 2003 PathScale, Inc.
+ * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  *
  * Licensed under the GPL
  */
@@ -14,11 +15,6 @@
 #define MAX_REG_OFFSET (UM_FRAME_SIZE)
 #define MAX_REG_NR ((MAX_REG_OFFSET) / sizeof(unsigned long))
 
-#ifdef UML_CONFIG_MODE_TT
-#include "sysdep/sc.h"
-#endif
-
-#ifdef UML_CONFIG_MODE_SKAS
 #include "skas_ptregs.h"
 
 #define REGS_IP(r) ((r)[HOST_IP])
@@ -88,21 +84,10 @@
 
 #define REGS_ERR(r) ((r)->fault_type)
 
-#endif
-
 #include "choose-mode.h"
 
 /* XXX */
 union uml_pt_regs {
-#ifdef UML_CONFIG_MODE_TT
-	struct tt_regs {
-		long syscall;
-		unsigned long orig_rax;
-		void *sc;
-                struct faultinfo faultinfo;
-	} tt;
-#endif
-#ifdef UML_CONFIG_MODE_SKAS
 	struct skas_regs {
 		unsigned long regs[MAX_REG_NR];
 		unsigned long fp[HOST_FP_SIZE];
@@ -110,14 +95,10 @@ union uml_pt_regs {
 		long syscall;
 		int is_user;
 	} skas;
-#endif
 };
 
 #define EMPTY_UML_PT_REGS { }
 
-/* XXX */
-extern int mode_tt;
-
 #define UPT_RBX(r) __CHOOSE_MODE(SC_RBX(UPT_SC(r)), REGS_RBX((r)->skas.regs))
 #define UPT_RCX(r) __CHOOSE_MODE(SC_RCX(UPT_SC(r)), REGS_RCX((r)->skas.regs))
 #define UPT_RDX(r) __CHOOSE_MODE(SC_RDX(UPT_SC(r)), REGS_RDX((r)->skas.regs))
diff --git a/arch/um/include/sysdep-x86_64/thread.h b/arch/um/include/sysdep-x86_64/thread.h
index cbef3e1697f..d73d0b0afdb 100644
--- a/arch/um/include/sysdep-x86_64/thread.h
+++ b/arch/um/include/sysdep-x86_64/thread.h
@@ -3,8 +3,4 @@
 
 #include <kern_constants.h>
 
-#ifdef UML_CONFIG_MODE_TT
-#define TASK_EXTERN_PID(task) *((int *) &(((char *) (task))[HOST_TASK_EXTERN_PID]))
-#endif
-
 #endif
diff --git a/arch/um/include/tt/debug.h b/arch/um/include/tt/debug.h
deleted file mode 100644
index 9778fa83829..00000000000
--- a/arch/um/include/tt/debug.h
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
- * Copyright (C) 2000, 2001, 2002  Jeff Dike (jdike@karaya.com) and
- * Lars Brinkhoff.
- * Licensed under the GPL
- */
-
-#ifndef __UML_TT_DEBUG_H
-#define __UML_TT_DEBUG_H
-
-extern int debugger_proxy(int status, pid_t pid);
-extern void child_proxy(pid_t pid, int status);
-extern void init_proxy (pid_t pid, int waiting, int status);
-extern int start_debugger(char *prog, int startup, int stop, int *debugger_fd);
-extern void fake_child_exit(void);
-extern int gdb_config(char *str);
-extern int gdb_remove(int unused);
-
-#endif
diff --git a/arch/um/include/tt/mmu-tt.h b/arch/um/include/tt/mmu-tt.h
deleted file mode 100644
index 572a78b2258..00000000000
--- a/arch/um/include/tt/mmu-tt.h
+++ /dev/null
@@ -1,12 +0,0 @@
-/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- * Licensed under the GPL
- */
-
-#ifndef __TT_MMU_H
-#define __TT_MMU_H
-
-struct mmu_context_tt {
-};
-
-#endif
diff --git a/arch/um/include/tt/mode-tt.h b/arch/um/include/tt/mode-tt.h
deleted file mode 100644
index 2823cd56eea..00000000000
--- a/arch/um/include/tt/mode-tt.h
+++ /dev/null
@@ -1,23 +0,0 @@
-/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- * Licensed under the GPL
- */
-
-#ifndef __MODE_TT_H__
-#define __MODE_TT_H__
-
-#include "sysdep/ptrace.h"
-
-enum { OP_NONE, OP_EXEC, OP_FORK, OP_TRACE_ON, OP_REBOOT, OP_HALT, OP_CB };
-
-extern int tracing_pid;
-
-extern int tracer(int (*init_proc)(void *), void *sp);
-extern void sig_handler_common_tt(int sig, void *sc);
-extern void syscall_handler_tt(int sig, union uml_pt_regs *regs);
-extern void reboot_tt(void);
-extern void halt_tt(void);
-extern int is_tracer_winch(int pid, int fd, void *data);
-extern void kill_off_processes_tt(void);
-
-#endif
diff --git a/arch/um/include/tt/mode_kern_tt.h b/arch/um/include/tt/mode_kern_tt.h
deleted file mode 100644
index a4fc6305719..00000000000
--- a/arch/um/include/tt/mode_kern_tt.h
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- * Licensed under the GPL
- */
-
-#ifndef __TT_MODE_KERN_H__
-#define __TT_MODE_KERN_H__
-
-#include "linux/sched.h"
-#include "asm/page.h"
-#include "asm/ptrace.h"
-#include "asm/uaccess.h"
-
-extern void switch_to_tt(void *prev, void *next);
-extern void flush_thread_tt(void);
-extern void start_thread_tt(struct pt_regs *regs, unsigned long eip,
-			   unsigned long esp);
-extern int copy_thread_tt(int nr, unsigned long clone_flags, unsigned long sp,
-			  unsigned long stack_top, struct task_struct *p,
-			  struct pt_regs *regs);
-extern void release_thread_tt(struct task_struct *task);
-extern void initial_thread_cb_tt(void (*proc)(void *), void *arg);
-extern void init_idle_tt(void);
-extern void flush_tlb_kernel_range_tt(unsigned long start, unsigned long end);
-extern void flush_tlb_kernel_vm_tt(void);
-extern void __flush_tlb_one_tt(unsigned long addr);
-extern void flush_tlb_range_tt(struct vm_area_struct *vma,
-			       unsigned long start, unsigned long end);
-extern void flush_tlb_mm_tt(struct mm_struct *mm);
-extern void force_flush_all_tt(void);
-extern long execute_syscall_tt(void *r);
-extern void before_mem_tt(unsigned long brk_start);
-extern unsigned long set_task_sizes_tt(unsigned long *task_size_out);
-extern int start_uml_tt(void);
-extern int external_pid_tt(struct task_struct *task);
-extern int thread_pid_tt(struct task_struct *task);
-
-#define kmem_end_tt (host_task_size - ABOVE_KMEM)
-
-#endif
diff --git a/arch/um/include/tt/tt.h b/arch/um/include/tt/tt.h
deleted file mode 100644
index acb8356e1f9..00000000000
--- a/arch/um/include/tt/tt.h
+++ /dev/null
@@ -1,37 +0,0 @@
-/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- * Licensed under the GPL
- */
-
-#ifndef __TT_H__
-#define __TT_H__
-
-#include "sysdep/ptrace.h"
-
-extern int gdb_pid;
-extern int debug;
-extern int debug_stop;
-extern int debug_trace;
-
-extern int honeypot;
-
-extern int fork_tramp(void *sig_stack);
-extern int do_proc_op(void *t, int proc_id);
-extern int tracer(int (*init_proc)(void *), void *sp);
-extern void attach_process(int pid);
-extern void tracer_panic(char *format, ...)
-	__attribute__ ((format (printf, 1, 2)));
-extern void set_init_pid(int pid);
-extern int set_user_mode(void *task);
-extern void set_tracing(void *t, int tracing);
-extern int is_tracing(void *task);
-extern void syscall_handler(int sig, union uml_pt_regs *regs);
-extern void exit_kernel(int pid, void *task);
-extern void do_syscall(void *task, int pid, int local_using_sysemu);
-extern void do_sigtrap(void *task);
-extern int is_valid_pid(int pid);
-extern void remap_data(void *segment_start, void *segment_end, int w);
-extern long execute_syscall_tt(void *r);
-
-#endif
-
diff --git a/arch/um/include/tt/uaccess-tt.h b/arch/um/include/tt/uaccess-tt.h
deleted file mode 100644
index 13a64f61fcf..00000000000
--- a/arch/um/include/tt/uaccess-tt.h
+++ /dev/null
@@ -1,46 +0,0 @@
-/*
- * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
- * Licensed under the GPL
- */
-
-#ifndef __TT_UACCESS_H
-#define __TT_UACCESS_H
-
-#include "linux/string.h"
-#include "linux/sched.h"
-#include "asm/processor.h"
-#include "asm/errno.h"
-#include "asm/current.h"
-#include "asm/a.out.h"
-#include "uml_uaccess.h"
-
-#define ABOVE_KMEM (16 * 1024 * 1024)
-
-extern unsigned long end_vm;
-extern unsigned long uml_physmem;
-
-#define is_stack(addr, size) \
-	(((unsigned long) (addr) < STACK_TOP) && \
-	 ((unsigned long) (addr) >= STACK_TOP - ABOVE_KMEM) && \
-	 (((unsigned long) (addr) + (size)) <= STACK_TOP))
-
-#define access_ok_tt(type, addr, size) \
-	(is_stack(addr, size))
-
-extern int __do_copy_from_user(void *to, const void *from, int n,
-			       void **fault_addr, void **fault_catcher);
-extern int __do_strncpy_from_user(char *dst, const char *src, size_t n,
-				  void **fault_addr, void **fault_catcher);
-extern int __do_clear_user(void *mem, size_t len, void **fault_addr,
-			   void **fault_catcher);
-extern int __do_strnlen_user(const char *str, unsigned long n,
-			     void **fault_addr, void **fault_catcher);
-
-extern int copy_from_user_tt(void *to, const void __user *from, int n);
-extern int copy_to_user_tt(void __user *to, const void *from, int n);
-extern int strncpy_from_user_tt(char *dst, const char __user *src, int count);
-extern int __clear_user_tt(void __user *mem, int len);
-extern int clear_user_tt(void __user *mem, int len);
-extern int strnlen_user_tt(const void __user *str, int len);
-
-#endif
diff --git a/arch/um/include/um_mmu.h b/arch/um/include/um_mmu.h
index 0fa64323830..2461be6b0a6 100644
--- a/arch/um/include/um_mmu.h
+++ b/arch/um/include/um_mmu.h
@@ -8,33 +8,10 @@
 
 #include "uml-config.h"
 #include "choose-mode.h"
-
-#ifdef UML_CONFIG_MODE_TT
-#include "mmu-tt.h"
-#endif
-
-#ifdef UML_CONFIG_MODE_SKAS
 #include "mmu-skas.h"
-#endif
 
 typedef union mm_context {
-#ifdef UML_CONFIG_MODE_TT
-	struct mmu_context_tt tt;
-#endif
-#ifdef UML_CONFIG_MODE_SKAS
 	struct mmu_context_skas skas;
-#endif
 } mm_context_t;
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/include/um_uaccess.h b/arch/um/include/um_uaccess.h
index 5126a99b596..6757ee768cc 100644
--- a/arch/um/include/um_uaccess.h
+++ b/arch/um/include/um_uaccess.h
@@ -7,15 +7,7 @@
 #define __ARCH_UM_UACCESS_H
 
 #include "choose-mode.h"
-
-#ifdef CONFIG_MODE_TT
-#include "uaccess-tt.h"
-#endif
-
-#ifdef CONFIG_MODE_SKAS
 #include "uaccess-skas.h"
-#endif
-
 #include "asm/fixmap.h"
 
 #define __under_task_size(addr, size) \