[PATCH] Centralize i386 Constants

__FIXADDR_TOP and PAGE_OFFSET are hardcoded in various places.  I had to
change it to run the kernel under qemu-fast, so I wanted to centralize
them.

To do this, we rename vsyscall.lds to vsyscall.lds.s, and generate it from
vsyscall.lds.S.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (created)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/i386/kernel/Makefile

@@ -47,12 +47,14 @@ quiet_cmd_syscall = SYSCALL $@
       cmd_syscall = $(CC) -nostdlib $(SYSCFLAGS_$(@F)) \
 		          -Wl,-T,$(filter-out FORCE,$^) -o $@
 
+export AFLAGS_vsyscall.lds.o += -P -C -U$(ARCH)
+
 vsyscall-flags = -shared -s -Wl,-soname=linux-gate.so.1
 SYSCFLAGS_vsyscall-sysenter.so	= $(vsyscall-flags)
 SYSCFLAGS_vsyscall-int80.so	= $(vsyscall-flags)
 
 $(obj)/vsyscall-int80.so $(obj)/vsyscall-sysenter.so: \
-$(obj)/vsyscall-%.so: $(src)/vsyscall.lds $(obj)/vsyscall-%.o FORCE
+$(obj)/vsyscall-%.so: $(src)/vsyscall.lds.s $(obj)/vsyscall-%.o FORCE
 	$(call if_changed,syscall)
 
 # We also create a special relocatable object that should mirror the symbol
@@ -63,5 +65,5 @@ $(obj)/built-in.o: $(obj)/vsyscall-syms.o
 $(obj)/built-in.o: ld_flags += -R $(obj)/vsyscall-syms.o
 
 SYSCFLAGS_vsyscall-syms.o = -r
-$(obj)/vsyscall-syms.o: $(src)/vsyscall.lds $(obj)/vsyscall-sysenter.o FORCE
+$(obj)/vsyscall-syms.o: $(src)/vsyscall.lds.s $(obj)/vsyscall-sysenter.o FORCE
 	$(call if_changed,syscall)

arch/i386/kernel/vmlinux.lds.S

@@ -4,6 +4,7 @@
 
 #include <asm-generic/vmlinux.lds.h>
 #include <asm/thread_info.h>
+#include <asm/page.h>
 
 OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386")
 OUTPUT_ARCH(i386)
@@ -11,7 +12,7 @@ ENTRY(startup_32)
 jiffies = jiffies_64;
 SECTIONS
 {
-  . = 0xC0000000 + 0x100000;
+  . = __PAGE_OFFSET + 0x100000;
   /* read-only */
   _text = .;			/* Text and read-only data */
   .text : {

arch/i386/kernel/vsyscall.lds → arch/i386/kernel/vsyscall.lds.S

@@ -3,9 +3,9 @@
  * object prelinked to its virtual address, and with only one read-only
  * segment (that fits in one page).  This script controls its layout.
  */
+#include <asm/fixmap.h>
 
-/* This must match <asm/fixmap.h>.  */
-VSYSCALL_BASE = 0xffffe000;
+VSYSCALL_BASE = __FIXADDR_TOP - 0x1000;
 
 SECTIONS
 {

include/asm-i386/fixmap.h

@@ -14,6 +14,15 @@
 #define _ASM_FIXMAP_H
 
 #include <linux/config.h>
+
+/* used by vmalloc.c, vsyscall.lds.S.
+ *
+ * Leave one empty page between vmalloc'ed areas and
+ * the start of the fixmap.
+ */
+#define __FIXADDR_TOP	0xfffff000
+
+#ifndef __ASSEMBLY__
 #include <linux/kernel.h>
 #include <asm/acpi.h>
 #include <asm/apicdef.h>
@@ -97,13 +106,8 @@ extern void __set_fixmap (enum fixed_addresses idx,
 #define clear_fixmap(idx) \
 		__set_fixmap(idx, 0, __pgprot(0))
 
-/*
- * used by vmalloc.c.
- *
- * Leave one empty page between vmalloc'ed areas and
- * the start of the fixmap.
- */
-#define FIXADDR_TOP	(0xfffff000UL)
+#define FIXADDR_TOP	((unsigned long)__FIXADDR_TOP)
+
 #define __FIXADDR_SIZE	(__end_of_permanent_fixed_addresses << PAGE_SHIFT)
 #define FIXADDR_START	(FIXADDR_TOP - __FIXADDR_SIZE)
 
@@ -148,4 +152,5 @@ static inline unsigned long virt_to_fix(const unsigned long vaddr)
 	return __virt_to_fix(vaddr);
 }
 
+#endif /* !__ASSEMBLY__ */
 #endif