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authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2009-03-19 19:34:11 +0000
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>2009-03-24 13:47:33 +1100
commitd62cbf45a84d442a6b79d993c05edfb283bab8f8 (patch)
tree930ba143139eb299d045c040175789a3efb541b2 /arch/powerpc/mm/mmap.c
parent71087002cf807e25056dba4e4028a9f204dc9ffd (diff)
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powerpc/mm: Rename arch/powerpc/kernel/mmap.c to mmap_64.c
This file is only useful on 64-bit, so we name it accordingly. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/mm/mmap.c')
-rw-r--r--arch/powerpc/mm/mmap.c109
1 files changed, 0 insertions, 109 deletions
diff --git a/arch/powerpc/mm/mmap.c b/arch/powerpc/mm/mmap.c
deleted file mode 100644
index 0d957a4c70fe..000000000000
--- a/arch/powerpc/mm/mmap.c
+++ /dev/null
@@ -1,109 +0,0 @@
-/*
- * 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>
-#include <linux/random.h>
-#include <linux/sched.h>
-
-/*
- * Top of mmap area (just below the process stack).
- *
- * Leave at least a ~128 MB hole on 32bit applications.
- *
- * On 64bit applications we randomise the stack by 1GB so we need to
- * space our mmap start address by a further 1GB, otherwise there is a
- * chance the mmap area will end up closer to the stack than our ulimit
- * requires.
- */
-#define MIN_GAP32 (128*1024*1024)
-#define MIN_GAP64 ((128 + 1024)*1024*1024UL)
-#define MIN_GAP ((is_32bit_task()) ? MIN_GAP32 : MIN_GAP64)
-#define MAX_GAP (TASK_SIZE/6*5)
-
-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;
-}
-
-/*
- * Since get_random_int() returns the same value within a 1 jiffy window,
- * we will almost always get the same randomisation for the stack and mmap
- * region. This will mean the relative distance between stack and mmap will
- * be the same.
- *
- * To avoid this we can shift the randomness by 1 bit.
- */
-static unsigned long mmap_rnd(void)
-{
- unsigned long rnd = 0;
-
- if (current->flags & PF_RANDOMIZE) {
- /* 8MB for 32bit, 1GB for 64bit */
- if (is_32bit_task())
- rnd = (long)(get_random_int() % (1<<(22-PAGE_SHIFT)));
- else
- rnd = (long)(get_random_int() % (1<<(29-PAGE_SHIFT)));
- }
- return (rnd << PAGE_SHIFT) * 2;
-}
-
-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 PAGE_ALIGN(TASK_SIZE - gap - mmap_rnd());
-}
-
-/*
- * 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;
- }
-}