Revert x86-64 flexmap code for now

For some as-yet unclear reason, it seems to break legacy
32-bit apps on x86-64.

Cset exclude: ak@suse.de[torvalds]|ChangeSet|20041102230307|11901

arch/x86_64/mm/Makefile

@@ -2,7 +2,7 @@
 # Makefile for the linux x86_64-specific parts of the memory manager.
 #
 
-obj-y	 := init.o fault.o ioremap.o extable.o pageattr.o mmap.o
+obj-y	 := init.o fault.o ioremap.o extable.o pageattr.o
 obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
 obj-$(CONFIG_DISCONTIGMEM) += numa.o
 obj-$(CONFIG_K8_NUMA) += k8topology.o

arch/x86_64/mm/mmap.c

-/*
- *  linux/arch/x86-64/mm/mmap.c
- *
- *  flexible mmap layout support
- *
- * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
- * All Rights Reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *
- *
- * Started by Ingo Molnar <mingo@elte.hu>
- */
-
-#include <linux/personality.h>
-#include <linux/mm.h>
-
-/*
- * Top of mmap area (just below the process stack).
- *
- * Leave an at least ~128 MB hole, 4GB for 64bit.
- */
-#define MIN_GAP (test_thread_flag(TIF_IA32) ? 4UL*1024*1024*1024 : 128*1024*1024)
-#define MAX_GAP (TASK_SIZE/6*5)
-
-static inline unsigned long mmap_base(void)
-{
-	unsigned long gap = current->signal->rlim[RLIMIT_STACK].rlim_cur;
-
-	if (gap < MIN_GAP)
-		gap = MIN_GAP;
-	else if (gap > MAX_GAP)
-		gap = MAX_GAP;
-
-	return TASK_SIZE - (gap & PAGE_MASK);
-}
-
-static inline int mmap_is_legacy(void)
-{
-	if (current->personality & ADDR_COMPAT_LAYOUT)
-		return 1;
-
-	if (current->signal->rlim[RLIMIT_STACK].rlim_cur == RLIM_INFINITY)
-		return 1;
-
-	return sysctl_legacy_va_layout;
-}
-
-/*
- * This function, called very early during the creation of a new
- * process VM image, sets up which VM layout function to use:
- */
-void arch_pick_mmap_layout(struct mm_struct *mm)
-{
-	/*
-	 * Fall back to the standard layout if the personality
-	 * bit is set, or if the expected stack growth is unlimited:
-	 */
-	if (mmap_is_legacy()) {
-		mm->mmap_base = TASK_UNMAPPED_BASE;
-		mm->get_unmapped_area = arch_get_unmapped_area;
-		mm->unmap_area = arch_unmap_area;
-	} else {
-		mm->mmap_base = mmap_base();
-		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
-		mm->unmap_area = arch_unmap_area_topdown;
-	}
-}

include/asm-x86_64/processor.h

@@ -164,6 +164,10 @@ static inline void clear_in_cr4 (unsigned long mask)
 #define MCA_bus__is_a_macro
 
 
+/*
+ * User space process size: 512GB - 1GB (default).
+ */
+#define TASK_SIZE	(0x0000007fc0000000UL)
 
 /* This decides where the kernel will search for a free chunk of vm
  * space during mmap's.
@@ -174,14 +178,6 @@ static inline void clear_in_cr4 (unsigned long mask)
 #define TASK_UNMAPPED_BASE	\
 	(test_thread_flag(TIF_IA32) ? TASK_UNMAPPED_32 : TASK_UNMAPPED_64)  
 
-
-/*
- * User space process size: 512GB - 1GB (default).
- */
-#define TASK_SIZE_64	(0x0000007fc0000000UL)
-
-#define TASK_SIZE (test_thread_flag(TIF_IA32) ? IA32_PAGE_OFFSET : TASK_SIZE_64)
-
 /*
  * Size of io_bitmap.
  */
@@ -465,6 +461,4 @@ static inline void __mwait(unsigned long eax, unsigned long ecx)
 
 #define cache_line_size() (boot_cpu_data.x86_cache_alignment)
 
-#define HAVE_ARCH_PICK_MMAP_LAYOUT
-
 #endif /* __ASM_X86_64_PROCESSOR_H */