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-rw-r--r--arch/powerpc/mm/mmap.c256
1 files changed, 0 insertions, 256 deletions
diff --git a/arch/powerpc/mm/mmap.c b/arch/powerpc/mm/mmap.c
deleted file mode 100644
index c475cf810aa8..000000000000
--- a/arch/powerpc/mm/mmap.c
+++ /dev/null
@@ -1,256 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * flexible mmap layout support
- *
- * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
- * All Rights Reserved.
- *
- * Started by Ingo Molnar <mingo@elte.hu>
- */
-
-#include <linux/personality.h>
-#include <linux/mm.h>
-#include <linux/random.h>
-#include <linux/sched/signal.h>
-#include <linux/sched/mm.h>
-#include <linux/elf-randomize.h>
-#include <linux/security.h>
-#include <linux/mman.h>
-
-/*
- * Top of mmap area (just below the process stack).
- *
- * Leave at least a ~128 MB hole.
- */
-#define MIN_GAP (128*1024*1024)
-#define MAX_GAP (TASK_SIZE/6*5)
-
-static inline int mmap_is_legacy(struct rlimit *rlim_stack)
-{
- if (current->personality & ADDR_COMPAT_LAYOUT)
- return 1;
-
- if (rlim_stack->rlim_cur == RLIM_INFINITY)
- return 1;
-
- return sysctl_legacy_va_layout;
-}
-
-unsigned long arch_mmap_rnd(void)
-{
- unsigned long shift, rnd;
-
- shift = mmap_rnd_bits;
-#ifdef CONFIG_COMPAT
- if (is_32bit_task())
- shift = mmap_rnd_compat_bits;
-#endif
- rnd = get_random_long() % (1ul << shift);
-
- return rnd << PAGE_SHIFT;
-}
-
-static inline unsigned long stack_maxrandom_size(void)
-{
- if (!(current->flags & PF_RANDOMIZE))
- return 0;
-
- /* 8MB for 32bit, 1GB for 64bit */
- if (is_32bit_task())
- return (1<<23);
- else
- return (1<<30);
-}
-
-static inline unsigned long mmap_base(unsigned long rnd,
- struct rlimit *rlim_stack)
-{
- unsigned long gap = rlim_stack->rlim_cur;
- unsigned long pad = stack_maxrandom_size() + stack_guard_gap;
-
- /* Values close to RLIM_INFINITY can overflow. */
- if (gap + pad > gap)
- gap += pad;
-
- if (gap < MIN_GAP)
- gap = MIN_GAP;
- else if (gap > MAX_GAP)
- gap = MAX_GAP;
-
- return PAGE_ALIGN(DEFAULT_MAP_WINDOW - gap - rnd);
-}
-
-#ifdef HAVE_ARCH_UNMAPPED_AREA
-#ifdef CONFIG_PPC_RADIX_MMU
-/*
- * Same function as generic code used only for radix, because we don't need to overload
- * the generic one. But we will have to duplicate, because hash select
- * HAVE_ARCH_UNMAPPED_AREA
- */
-static unsigned long
-radix__arch_get_unmapped_area(struct file *filp, unsigned long addr,
- unsigned long len, unsigned long pgoff,
- unsigned long flags)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- int fixed = (flags & MAP_FIXED);
- unsigned long high_limit;
- struct vm_unmapped_area_info info;
-
- high_limit = DEFAULT_MAP_WINDOW;
- if (addr >= high_limit || (fixed && (addr + len > high_limit)))
- high_limit = TASK_SIZE;
-
- if (len > high_limit)
- return -ENOMEM;
-
- if (fixed) {
- if (addr > high_limit - len)
- return -ENOMEM;
- return addr;
- }
-
- if (addr) {
- addr = PAGE_ALIGN(addr);
- vma = find_vma(mm, addr);
- if (high_limit - len >= addr && addr >= mmap_min_addr &&
- (!vma || addr + len <= vm_start_gap(vma)))
- return addr;
- }
-
- info.flags = 0;
- info.length = len;
- info.low_limit = mm->mmap_base;
- info.high_limit = high_limit;
- info.align_mask = 0;
-
- return vm_unmapped_area(&info);
-}
-
-static unsigned long
-radix__arch_get_unmapped_area_topdown(struct file *filp,
- const unsigned long addr0,
- const unsigned long len,
- const unsigned long pgoff,
- const unsigned long flags)
-{
- struct vm_area_struct *vma;
- struct mm_struct *mm = current->mm;
- unsigned long addr = addr0;
- int fixed = (flags & MAP_FIXED);
- unsigned long high_limit;
- struct vm_unmapped_area_info info;
-
- high_limit = DEFAULT_MAP_WINDOW;
- if (addr >= high_limit || (fixed && (addr + len > high_limit)))
- high_limit = TASK_SIZE;
-
- if (len > high_limit)
- return -ENOMEM;
-
- if (fixed) {
- if (addr > high_limit - len)
- return -ENOMEM;
- return addr;
- }
-
- if (addr) {
- addr = PAGE_ALIGN(addr);
- vma = find_vma(mm, addr);
- if (high_limit - len >= addr && addr >= mmap_min_addr &&
- (!vma || addr + len <= vm_start_gap(vma)))
- return addr;
- }
-
- info.flags = VM_UNMAPPED_AREA_TOPDOWN;
- info.length = len;
- info.low_limit = max(PAGE_SIZE, mmap_min_addr);
- info.high_limit = mm->mmap_base + (high_limit - DEFAULT_MAP_WINDOW);
- info.align_mask = 0;
-
- addr = vm_unmapped_area(&info);
- if (!(addr & ~PAGE_MASK))
- return addr;
- VM_BUG_ON(addr != -ENOMEM);
-
- /*
- * A failed mmap() very likely causes application failure,
- * so fall back to the bottom-up function here. This scenario
- * can happen with large stack limits and large mmap()
- * allocations.
- */
- return radix__arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
-}
-#endif
-
-unsigned long arch_get_unmapped_area(struct file *filp,
- unsigned long addr,
- unsigned long len,
- unsigned long pgoff,
- unsigned long flags)
-{
-#ifdef CONFIG_PPC_MM_SLICES
- return slice_get_unmapped_area(addr, len, flags,
- mm_ctx_user_psize(&current->mm->context), 0);
-#else
- BUG();
-#endif
-}
-
-unsigned long arch_get_unmapped_area_topdown(struct file *filp,
- const unsigned long addr0,
- const unsigned long len,
- const unsigned long pgoff,
- const unsigned long flags)
-{
-#ifdef CONFIG_PPC_MM_SLICES
- return slice_get_unmapped_area(addr0, len, flags,
- mm_ctx_user_psize(&current->mm->context), 1);
-#else
- BUG();
-#endif
-}
-#endif /* HAVE_ARCH_UNMAPPED_AREA */
-
-static void radix__arch_pick_mmap_layout(struct mm_struct *mm,
- unsigned long random_factor,
- struct rlimit *rlim_stack)
-{
-#ifdef CONFIG_PPC_RADIX_MMU
- if (mmap_is_legacy(rlim_stack)) {
- mm->mmap_base = TASK_UNMAPPED_BASE;
- mm->get_unmapped_area = radix__arch_get_unmapped_area;
- } else {
- mm->mmap_base = mmap_base(random_factor, rlim_stack);
- mm->get_unmapped_area = radix__arch_get_unmapped_area_topdown;
- }
-#endif
-}
-
-/*
- * 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, struct rlimit *rlim_stack)
-{
- unsigned long random_factor = 0UL;
-
- if (current->flags & PF_RANDOMIZE)
- random_factor = arch_mmap_rnd();
-
- if (radix_enabled())
- return radix__arch_pick_mmap_layout(mm, random_factor,
- rlim_stack);
- /*
- * Fall back to the standard layout if the personality
- * bit is set, or if the expected stack growth is unlimited:
- */
- if (mmap_is_legacy(rlim_stack)) {
- mm->mmap_base = TASK_UNMAPPED_BASE;
- mm->get_unmapped_area = arch_get_unmapped_area;
- } else {
- mm->mmap_base = mmap_base(random_factor, rlim_stack);
- mm->get_unmapped_area = arch_get_unmapped_area_topdown;
- }
-}
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