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>

1 files changed, 0 insertions, 16 deletions

diff --git a/arch/um/sys-i386/tls.c b/arch/um/sys-i386/tls.c
index fea8e5e15cc4..0340b96d101b 100644
--- a/arch/um/sys-i386/tls.c
+++ b/arch/um/sys-i386/tls.c
@@ -18,10 +18,7 @@
 #include "mode_kern.h"
 #include "os.h"
 #include "mode.h"
-
-#ifdef CONFIG_MODE_SKAS
 #include "skas.h"
-#endif
 
 /*
  * If needed we can detect when it's uninitialized.
@@ -31,7 +28,6 @@
 static int host_supports_tls = -1;
 int host_gdt_entry_tls_min;
 
-#ifdef CONFIG_MODE_SKAS
 int do_set_thread_area_skas(struct user_desc *info)
 {
 	int ret;
@@ -53,7 +49,6 @@ int do_get_thread_area_skas(struct user_desc *info)
 	put_cpu();
 	return ret;
 }
-#endif
 
 /*
  * sys_get_thread_area: get a yet unused TLS descriptor index.
@@ -187,17 +182,6 @@ int arch_switch_tls_skas(struct task_struct *from, struct task_struct *to)
 	return 0;
 }
 
-int arch_switch_tls_tt(struct task_struct *from, struct task_struct *to)
-{
-	if (!host_supports_tls)
-		return 0;
-
-	if (needs_TLS_update(to))
-		return load_TLS(0, to);
-
-	return 0;
-}
-
 static int set_tls_entry(struct task_struct* task, struct user_desc *info,
 			 int idx, int flushed)
 {