x86, um: merge Kconfig.i386 and Kconfig.x86_64

Signed-off-by: Al Viro <[email protected]>
Signed-off-by: H. Peter Anvin <[email protected]>

arch/um/Kconfig

@@ -85,6 +85,10 @@ config STATIC_LINK
 	  Additionally, this option enables using higher memory spaces (up to
 	  2.75G) for UML.
 
+config SUBARCH
+	string
+	option env="SUBARCH"
+
 source "arch/um/Kconfig.arch"
 source "mm/Kconfig"
 source "kernel/time/Kconfig"

arch/um/Kconfig.i386 → arch/um/Kconfig.x86

@@ -5,24 +5,25 @@ source "arch/x86/Kconfig.cpu"
 endmenu
 
 config UML_X86
+	def_bool y
+
+config 64BIT
 	bool
-	default y
+	default SUBARCH = "x86_64"
 
 config X86_32
-	bool
-	default y
-  	select HAVE_AOUT
+	def_bool !64BIT
+	select HAVE_AOUT
 
 config RWSEM_XCHGADD_ALGORITHM
-	def_bool y
+	def_bool X86_XADD
 
-config 64BIT
-	bool
-	default n
+config RWSEM_GENERIC_SPINLOCK
+	def_bool !X86_XADD
 
 config 3_LEVEL_PGTABLES
-	bool "Three-level pagetables (EXPERIMENTAL)"
-	default n
+	bool "Three-level pagetables (EXPERIMENTAL)" if !64BIT
+	default 64BIT
 	depends on EXPERIMENTAL
 	help
 	Three-level pagetables will let UML have more than 4G of physical
@@ -33,13 +34,13 @@ config 3_LEVEL_PGTABLES
 	N (on x86-64 it's automatically enabled, instead, as it's safe there).
 
 config ARCH_HAS_SC_SIGNALS
-	bool
-	default y
+	def_bool !64BIT
 
 config ARCH_REUSE_HOST_VSYSCALL_AREA
-	bool
-	default y
+	def_bool !64BIT
+
+config SMP_BROKEN
+	def_bool 64BIT
 
 config GENERIC_HWEIGHT
-	bool
-	default y
+	def_bool y

arch/um/Makefile

@@ -96,9 +96,9 @@ define archhelp
 endef
 
 ifneq ($(KBUILD_SRC),)
-$(shell mkdir -p $(ARCH_DIR) && ln -fsn $(srctree)/$(ARCH_DIR)/Kconfig.$(SUBARCH) $(ARCH_DIR)/Kconfig.arch)
+$(shell mkdir -p $(ARCH_DIR) && ln -fsn $(srctree)/$(ARCH_DIR)/Kconfig.$(HEADER_ARCH) $(ARCH_DIR)/Kconfig.arch)
 else
-$(shell ln -fsn Kconfig.$(SUBARCH) $(ARCH_DIR)/Kconfig.arch)
+$(shell ln -fsn Kconfig.$(HEADER_ARCH) $(ARCH_DIR)/Kconfig.arch)
 endif
 
 archprepare: $(ARCH_SYMLINKS) $(ARCH_DIR)/include/shared/user_constants.h