Release 4.11 mm/mremap.c

/*
 *      mm/mremap.c
 *
 *      (C) Copyright 1996 Linus Torvalds
 *
 *      Address space accounting code   <alan@lxorguk.ukuu.org.uk>
 *      (C) Copyright 2002 Red Hat Inc, All Rights Reserved
 */

#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/shm.h>
#include <linux/ksm.h>
#include <linux/mman.h>
#include <linux/swap.h>
#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/swapops.h>
#include <linux/highmem.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/mmu_notifier.h>
#include <linux/uaccess.h>
#include <linux/mm-arch-hooks.h>
#include <linux/userfaultfd_k.h>

#include <asm/cacheflush.h>
#include <asm/tlbflush.h>

#include "internal.h"



static pmd_t *get_old_pmd(struct mm_struct *mm, unsigned long addr)
{
	pgd_t *pgd;
	p4d_t *p4d;
	pud_t *pud;
	pmd_t *pmd;

	pgd = pgd_offset(mm, addr);
	if (pgd_none_or_clear_bad(pgd))
		return NULL;

	p4d = p4d_offset(pgd, addr);
	if (p4d_none_or_clear_bad(p4d))
		return NULL;

	pud = pud_offset(p4d, addr);
	if (pud_none_or_clear_bad(pud))
		return NULL;

	pmd = pmd_offset(pud, addr);
	if (pmd_none(*pmd))
		return NULL;

	return pmd;
}

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Andrew Morton
58
51.79%
2
25.00%
Kirill A. Shutemov
24
21.43%
1
12.50%
Andi Kleen
22
19.64%
1
12.50%
Linus Torvalds (pre-git)
3
2.68%
1
12.50%
Hugh Dickins
3
2.68%
2
25.00%
Andrea Arcangeli
2
1.79%
1
12.50%
Total
112
100.00%
8
100.00%



static pmd_t *alloc_new_pmd(struct mm_struct *mm, struct vm_area_struct *vma,
			    unsigned long addr)
{
	pgd_t *pgd;
	p4d_t *p4d;
	pud_t *pud;
	pmd_t *pmd;

	pgd = pgd_offset(mm, addr);
	p4d = p4d_alloc(mm, pgd, addr);
	if (!p4d)
		return NULL;
	pud = pud_alloc(mm, p4d, addr);
	if (!pud)
		return NULL;

	pmd = pmd_alloc(mm, pud, addr);
	if (!pmd)
		return NULL;

	VM_BUG_ON(pmd_trans_huge(*pmd));

	return pmd;
}

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Linus Torvalds (pre-git)
34
29.57%
1
14.29%
Andi Kleen
30
26.09%
1
14.29%
Kirill A. Shutemov
24
20.87%
1
14.29%
Andrea Arcangeli
14
12.17%
1
14.29%
Hugh Dickins
11
9.57%
2
28.57%
Linus Torvalds
2
1.74%
1
14.29%
Total
115
100.00%
7
100.00%



static void take_rmap_locks(struct vm_area_struct *vma)
{
	if (vma->vm_file)
		i_mmap_lock_write(vma->vm_file->f_mapping);
	if (vma->anon_vma)
		anon_vma_lock_write(vma->anon_vma);
}

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39
100.00%
1
100.00%
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39
100.00%
1
100.00%



static void drop_rmap_locks(struct vm_area_struct *vma)
{
	if (vma->anon_vma)
		anon_vma_unlock_write(vma->anon_vma);
	if (vma->vm_file)
		i_mmap_unlock_write(vma->vm_file->f_mapping);
}

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39
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1
100.00%
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39
100.00%
1
100.00%



static pte_t move_soft_dirty_pte(pte_t pte)
{
	/*
         * Set soft dirty bit so we can notice
         * in userspace the ptes were moved.
         */
#ifdef CONFIG_MEM_SOFT_DIRTY
	if (pte_present(pte))
		pte = pte_mksoft_dirty(pte);
	else if (is_swap_pte(pte))
		pte = pte_swp_mksoft_dirty(pte);
#endif
	return pte;
}

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Cyrill V. Gorcunov
47
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1
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47
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1
100.00%



static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
		unsigned long old_addr, unsigned long old_end,
		struct vm_area_struct *new_vma, pmd_t *new_pmd,
		unsigned long new_addr, bool need_rmap_locks, bool *need_flush)
{
	struct mm_struct *mm = vma->vm_mm;
	pte_t *old_pte, *new_pte, pte;
	spinlock_t *old_ptl, *new_ptl;
	bool force_flush = false;
	unsigned long len = old_end - old_addr;

	/*
         * When need_rmap_locks is true, we take the i_mmap_rwsem and anon_vma
         * locks to ensure that rmap will always observe either the old or the
         * new ptes. This is the easiest way to avoid races with
         * truncate_pagecache(), page migration, etc...
         *
         * When need_rmap_locks is false, we use other ways to avoid
         * such races:
         *
         * - During exec() shift_arg_pages(), we use a specially tagged vma
         *   which rmap call sites look for using is_vma_temporary_stack().
         *
         * - During mremap(), new_vma is often known to be placed after vma
         *   in rmap traversal order. This ensures rmap will always observe
         *   either the old pte, or the new pte, or both (the page table locks
         *   serialize access to individual ptes, but only rmap traversal
         *   order guarantees that we won't miss both the old and new ptes).
         */
	if (need_rmap_locks)
		take_rmap_locks(vma);

	/*
         * We don't have to worry about the ordering of src and dst
         * pte locks because exclusive mmap_sem prevents deadlock.
         */
	old_pte = pte_offset_map_lock(mm, old_pmd, old_addr, &old_ptl);
	new_pte = pte_offset_map(new_pmd, new_addr);
	new_ptl = pte_lockptr(mm, new_pmd);
	if (new_ptl != old_ptl)
		spin_lock_nested(new_ptl, SINGLE_DEPTH_NESTING);
	arch_enter_lazy_mmu_mode();

	for (; old_addr < old_end; old_pte++, old_addr += PAGE_SIZE,
				   new_pte++, new_addr += PAGE_SIZE) {
		if (pte_none(*old_pte))
			continue;

		pte = ptep_get_and_clear(mm, old_addr, old_pte);
		/*
                 * If we are remapping a dirty PTE, make sure
                 * to flush TLB before we drop the PTL for the
                 * old PTE or we may race with page_mkclean().
                 *
                 * This check has to be done after we removed the
                 * old PTE from page tables or another thread may
                 * dirty it after the check and before the removal.
                 */
		if (pte_present(pte) && pte_dirty(pte))
			force_flush = true;
		pte = move_pte(pte, new_vma->vm_page_prot, old_addr, new_addr);
		pte = move_soft_dirty_pte(pte);
		set_pte_at(mm, new_addr, new_pte, pte);
	}

	arch_leave_lazy_mmu_mode();
	if (new_ptl != old_ptl)
		spin_unlock(new_ptl);
	pte_unmap(new_pte - 1);
	if (force_flush)
		flush_tlb_range(vma, old_end - len, old_end);
	else
		*need_flush = true;
	pte_unmap_unlock(old_pte - 1, old_ptl);
	if (need_rmap_locks)
		drop_rmap_locks(vma);
}

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Hugh Dickins
110
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5
19.23%
Aaron Lu
66
22.53%
2
7.69%
Linus Torvalds (pre-git)
26
8.87%
1
3.85%
Andrew Morton
26
8.87%
5
19.23%
Nicholas Piggin
13
4.44%
2
7.69%
Kanoj Sarcar
11
3.75%
1
3.85%
Michel Lespinasse
10
3.41%
2
7.69%
Ingo Molnar
8
2.73%
2
7.69%
Cyrill V. Gorcunov
7
2.39%
1
3.85%
Zachary Amsden
6
2.05%
1
3.85%
David S. Miller
5
1.71%
1
3.85%
Linus Torvalds
2
0.68%
1
3.85%
Peter Zijlstra
2
0.68%
1
3.85%
Davidlohr Bueso A
1
0.34%
1
3.85%
Total
293
100.00%
26
100.00%


#define LATENCY_LIMIT	(64 * PAGE_SIZE)



unsigned long move_page_tables(struct vm_area_struct *vma,
		unsigned long old_addr, struct vm_area_struct *new_vma,
		unsigned long new_addr, unsigned long len,
		bool need_rmap_locks)
{
	unsigned long extent, next, old_end;
	pmd_t *old_pmd, *new_pmd;
	bool need_flush = false;
	unsigned long mmun_start;	/* For mmu_notifiers */
	unsigned long mmun_end;		/* For mmu_notifiers */

	old_end = old_addr + len;
	flush_cache_range(vma, old_addr, old_end);

	mmun_start = old_addr;
	mmun_end   = old_end;
	mmu_notifier_invalidate_range_start(vma->vm_mm, mmun_start, mmun_end);

	for (; old_addr < old_end; old_addr += extent, new_addr += extent) {
		cond_resched();
		next = (old_addr + PMD_SIZE) & PMD_MASK;
		/* even if next overflowed, extent below will be ok */
		extent = next - old_addr;
		if (extent > old_end - old_addr)
			extent = old_end - old_addr;
		old_pmd = get_old_pmd(vma->vm_mm, old_addr);
		if (!old_pmd)
			continue;
		new_pmd = alloc_new_pmd(vma->vm_mm, vma, new_addr);
		if (!new_pmd)
			break;
		if (pmd_trans_huge(*old_pmd)) {
			if (extent == HPAGE_PMD_SIZE) {
				bool moved;
				/* See comment in move_ptes() */
				if (need_rmap_locks)
					take_rmap_locks(vma);
				moved = move_huge_pmd(vma, old_addr, new_addr,
						    old_end, old_pmd, new_pmd,
						    &need_flush);
				if (need_rmap_locks)
					drop_rmap_locks(vma);
				if (moved)
					continue;
			}
			split_huge_pmd(vma, old_pmd, old_addr);
			if (pmd_trans_unstable(old_pmd))
				continue;
		}
		if (pte_alloc(new_vma->vm_mm, new_pmd, new_addr))
			break;
		next = (new_addr + PMD_SIZE) & PMD_MASK;
		if (extent > next - new_addr)
			extent = next - new_addr;
		if (extent > LATENCY_LIMIT)
			extent = LATENCY_LIMIT;
		move_ptes(vma, old_pmd, old_addr, old_addr + extent, new_vma,
			  new_pmd, new_addr, need_rmap_locks, &need_flush);
	}
	if (need_flush)
		flush_tlb_range(vma, old_end-len, old_addr);

	mmu_notifier_invalidate_range_end(vma->vm_mm, mmun_start, mmun_end);

	return len + old_addr - old_end;	/* how much done */
}

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Hugh Dickins
145
39.19%
4
17.39%
Andrea Arcangeli
108
29.19%
4
17.39%
Linus Torvalds (pre-git)
36
9.73%
2
8.70%
Kirill A. Shutemov
35
9.46%
6
26.09%
Sagi Grimberg
22
5.95%
1
4.35%
Andrew Morton
8
2.16%
1
4.35%
Aaron Lu
6
1.62%
1
4.35%
Michel Lespinasse
5
1.35%
1
4.35%
Linus Torvalds
3
0.81%
1
4.35%
Naoya Horiguchi
1
0.27%
1
4.35%
Kanoj Sarcar
1
0.27%
1
4.35%
Total
370
100.00%
23
100.00%



static unsigned long move_vma(struct vm_area_struct *vma,
		unsigned long old_addr, unsigned long old_len,
		unsigned long new_len, unsigned long new_addr,
		bool *locked, struct vm_userfaultfd_ctx *uf,
		struct list_head *uf_unmap)
{
	struct mm_struct *mm = vma->vm_mm;
	struct vm_area_struct *new_vma;
	unsigned long vm_flags = vma->vm_flags;
	unsigned long new_pgoff;
	unsigned long moved_len;
	unsigned long excess = 0;
	unsigned long hiwater_vm;
	int split = 0;
	int err;
	bool need_rmap_locks;

	/*
         * We'd prefer to avoid failure later on in do_munmap:
         * which may split one vma into three before unmapping.
         */
	if (mm->map_count >= sysctl_max_map_count - 3)
		return -ENOMEM;

	/*
         * Advise KSM to break any KSM pages in the area to be moved:
         * it would be confusing if they were to turn up at the new
         * location, where they happen to coincide with different KSM
         * pages recently unmapped.  But leave vma->vm_flags as it was,
         * so KSM can come around to merge on vma and new_vma afterwards.
         */
	err = ksm_madvise(vma, old_addr, old_addr + old_len,
						MADV_UNMERGEABLE, &vm_flags);
	if (err)
		return err;

	new_pgoff = vma->vm_pgoff + ((old_addr - vma->vm_start) >> PAGE_SHIFT);
	new_vma = copy_vma(&vma, new_addr, new_len, new_pgoff,
			   &need_rmap_locks);
	if (!new_vma)
		return -ENOMEM;

	moved_len = move_page_tables(vma, old_addr, new_vma, new_addr, old_len,
				     need_rmap_locks);
	if (moved_len < old_len) {
		err = -ENOMEM;
	} else if (vma->vm_ops && vma->vm_ops->mremap) {
		err = vma->vm_ops->mremap(new_vma);
	}

	if (unlikely(err)) {
		/*
                 * On error, move entries back from new area to old,
                 * which will succeed since page tables still there,
                 * and then proceed to unmap new area instead of old.
                 */
		move_page_tables(new_vma, new_addr, vma, old_addr, moved_len,
				 true);
		vma = new_vma;
		old_len = new_len;
		old_addr = new_addr;
		new_addr = err;
	} else {
		mremap_userfaultfd_prep(new_vma, uf);
		arch_remap(mm, old_addr, old_addr + old_len,
			   new_addr, new_addr + new_len);
	}

	/* Conceal VM_ACCOUNT so old reservation is not undone */
	if (vm_flags & VM_ACCOUNT) {
		vma->vm_flags &= ~VM_ACCOUNT;
		excess = vma->vm_end - vma->vm_start - old_len;
		if (old_addr > vma->vm_start &&
		    old_addr + old_len < vma->vm_end)
			split = 1;
	}

	/*
         * If we failed to move page tables we still do total_vm increment
         * since do_munmap() will decrement it by old_len == new_len.
         *
         * Since total_vm is about to be raised artificially high for a
         * moment, we need to restore high watermark afterwards: if stats
         * are taken meanwhile, total_vm and hiwater_vm appear too high.
         * If this were a serious issue, we'd add a flag to do_munmap().
         */
	hiwater_vm = mm->hiwater_vm;
	vm_stat_account(mm, vma->vm_flags, new_len >> PAGE_SHIFT);

	/* Tell pfnmap has moved from this vma */
	if (unlikely(vma->vm_flags & VM_PFNMAP))
		untrack_pfn_moved(vma);

	if (do_munmap(mm, old_addr, old_len, uf_unmap) < 0) {
		/* OOM: unable to split vma, just get accounts right */
		vm_unacct_memory(excess >> PAGE_SHIFT);
		excess = 0;
	}
	mm->hiwater_vm = hiwater_vm;

	/* Restore VM_ACCOUNT if one or two pieces of vma left */
	if (excess) {
		vma->vm_flags |= VM_ACCOUNT;
		if (split)
			vma->vm_next->vm_flags |= VM_ACCOUNT;
	}

	if (vm_flags & VM_LOCKED) {
		mm->locked_vm += new_len >> PAGE_SHIFT;
		*locked = true;
	}

	return new_addr;
}

Contributors
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Hugh Dickins
124
26.33%
8
29.63%
Andrew Morton
109
23.14%
2
7.41%
Linus Torvalds (pre-git)
72
15.29%
5
18.52%
Pavel Emelyanov
30
6.37%
2
7.41%
Oleg Nesterov
27
5.73%
2
7.41%
Linus Torvalds
26
5.52%
2
7.41%
Al Viro
25
5.31%
1
3.70%
Laurent Dufour
18
3.82%
1
3.70%
Toshi Kani
17
3.61%
1
3.70%
Michel Lespinasse
16
3.40%
2
7.41%
Mike Rapoport
7
1.49%
1
3.70%
Total
471
100.00%
27
100.00%



static struct vm_area_struct *vma_to_resize(unsigned long addr,
	unsigned long old_len, unsigned long new_len, unsigned long *p)
{
	struct mm_struct *mm = current->mm;
	struct vm_area_struct *vma = find_vma(mm, addr);
	unsigned long pgoff;

	if (!vma || vma->vm_start > addr)
		return ERR_PTR(-EFAULT);

	if (is_vm_hugetlb_page(vma))
		return ERR_PTR(-EINVAL);

	/* We can't remap across vm area boundaries */
	if (old_len > vma->vm_end - addr)
		return ERR_PTR(-EFAULT);

	if (new_len == old_len)
		return vma;

	/* Need to be careful about a growing mapping */
	pgoff = (addr - vma->vm_start) >> PAGE_SHIFT;
	pgoff += vma->vm_pgoff;
	if (pgoff + (new_len >> PAGE_SHIFT) < pgoff)
		return ERR_PTR(-EINVAL);

	if (vma->vm_flags & (VM_DONTEXPAND | VM_PFNMAP))
		return ERR_PTR(-EFAULT);

	if (vma->vm_flags & VM_LOCKED) {
		unsigned long locked, lock_limit;
		locked = mm->locked_vm << PAGE_SHIFT;
		lock_limit = rlimit(RLIMIT_MEMLOCK);
		locked += new_len - old_len;
		if (locked > lock_limit && !capable(CAP_IPC_LOCK))
			return ERR_PTR(-EAGAIN);
	}

	if (!may_expand_vm(mm, vma->vm_flags,
				(new_len - old_len) >> PAGE_SHIFT))
		return ERR_PTR(-ENOMEM);

	if (vma->vm_flags & VM_ACCOUNT) {
		unsigned long charged = (new_len - old_len) >> PAGE_SHIFT;
		if (security_vm_enough_memory_mm(mm, charged))
			return ERR_PTR(-ENOMEM);
		*p = charged;
	}

	return vma;
}

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Al Viro
180
61.02%
2
28.57%
Derek
51
17.29%
1
14.29%
Linus Torvalds
31
10.51%
1
14.29%
Oleg Nesterov
26
8.81%
1
14.29%
Konstantin Khlebnikov
4
1.36%
1
14.29%
Jiri Slaby
3
1.02%
1
14.29%
Total
295
100.00%
7
100.00%



static unsigned long mremap_to(unsigned long addr, unsigned long old_len,
		unsigned long new_addr, unsigned long new_len, bool *locked,
		struct vm_userfaultfd_ctx *uf,
		struct list_head *uf_unmap)
{
	struct mm_struct *mm = current->mm;
	struct vm_area_struct *vma;
	unsigned long ret = -EINVAL;
	unsigned long charged = 0;
	unsigned long map_flags;

	if (offset_in_page(new_addr))
		goto out;

	if (new_len > TASK_SIZE || new_addr > TASK_SIZE - new_len)
		goto out;

	/* Ensure the old/new locations do not overlap */
	if (addr + old_len > new_addr && new_addr + new_len > addr)
		goto out;

	ret = do_munmap(mm, new_addr, new_len, NULL);
	if (ret)
		goto out;

	if (old_len >= new_len) {
		ret = do_munmap(mm, addr+new_len, old_len - new_len, uf_unmap);
		if (ret && old_len != new_len)
			goto out;
		old_len = new_len;
	}

	vma = vma_to_resize(addr, old_len, new_len, &charged);
	if (IS_ERR(vma)) {
		ret = PTR_ERR(vma);
		goto out;
	}

	map_flags = MAP_FIXED;
	if (vma->vm_flags & VM_MAYSHARE)
		map_flags |= MAP_SHARED;

	ret = get_unmapped_area(vma->vm_file, new_addr, new_len, vma->vm_pgoff +
				((addr - vma->vm_start) >> PAGE_SHIFT),
				map_flags);
	if (offset_in_page(ret))
		goto out1;

	ret = move_vma(vma, addr, old_len, new_len, new_addr, locked, uf,
		       uf_unmap);
	if (!(offset_in_page(ret)))
		goto out;
out1:
	vm_unacct_memory(charged);

out:
	return ret;
}

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Al Viro
132
43.00%
2
13.33%
Linus Torvalds (pre-git)
96
31.27%
5
33.33%
Andrew Morton
32
10.42%
2
13.33%
Mike Rapoport
11
3.58%
1
6.67%
Hugh Dickins
9
2.93%
1
6.67%
Alexander Kuleshov
9
2.93%
1
6.67%
Pavel Emelyanov
7
2.28%
1
6.67%
Michel Lespinasse
6
1.95%
1
6.67%
Oleg Nesterov
5
1.63%
1
6.67%
Total
307
100.00%
15
100.00%



static int vma_expandable(struct vm_area_struct *vma, unsigned long delta)
{
	unsigned long end = vma->vm_end + delta;
	if (end < vma->vm_end) /* overflow */
		return 0;
	if (vma->vm_next && vma->vm_next->vm_start < end) /* intersection */
		return 0;
	if (get_unmapped_area(NULL, vma->vm_start, end - vma->vm_start,
			      0, MAP_FIXED) & ~PAGE_MASK)
		return 0;
	return 1;
}

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CommitProp
Al Viro
85
100.00%
3
100.00%
Total
85
100.00%
3
100.00%

/*
 * Expand (or shrink) an existing mapping, potentially moving it at the
 * same time (controlled by the MREMAP_MAYMOVE flag and available VM space)
 *
 * MREMAP_FIXED option added 5-Dec-1999 by Benjamin LaHaise
 * This option implies MREMAP_MAYMOVE.
 */

SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
		unsigned long, new_len, unsigned long, flags,
		unsigned long, new_addr)
{
	struct mm_struct *mm = current->mm;
	struct vm_area_struct *vma;
	unsigned long ret = -EINVAL;
	unsigned long charged = 0;
	bool locked = false;
	struct vm_userfaultfd_ctx uf = NULL_VM_UFFD_CTX;
	LIST_HEAD(uf_unmap);

	if (flags & ~(MREMAP_FIXED | MREMAP_MAYMOVE))
		return ret;

	if (flags & MREMAP_FIXED && !(flags & MREMAP_MAYMOVE))
		return ret;

	if (offset_in_page(addr))
		return ret;

	old_len = PAGE_ALIGN(old_len);
	new_len = PAGE_ALIGN(new_len);

	/*
         * We allow a zero old-len as a special case
         * for DOS-emu "duplicate shm area" thing. But
         * a zero new-len is nonsensical.
         */
	if (!new_len)
		return ret;

	if (down_write_killable(&current->mm->mmap_sem))
		return -EINTR;

	if (flags & MREMAP_FIXED) {
		ret = mremap_to(addr, old_len, new_addr, new_len,
				&locked, &uf, &uf_unmap);
		goto out;
	}

	/*
         * Always allow a shrinking remap: that just unmaps
         * the unnecessary pages..
         * do_munmap does all the needed commit accounting
         */
	if (old_len >= new_len) {
		ret = do_munmap(mm, addr+new_len, old_len - new_len, &uf_unmap);
		if (ret && old_len != new_len)
			goto out;
		ret = addr;
		goto out;
	}

	/*
         * Ok, we need to grow..
         */
	vma = vma_to_resize(addr, old_len, new_len, &charged);
	if (IS_ERR(vma)) {
		ret = PTR_ERR(vma);
		goto out;
	}

	/* old_len exactly to the end of the area..
         */
	if (old_len == vma->vm_end - addr) {
		/* can we just expand the current mapping? */
		if (vma_expandable(vma, new_len - old_len)) {
			int pages = (new_len - old_len) >> PAGE_SHIFT;

			if (vma_adjust(vma, vma->vm_start, addr + new_len,
				       vma->vm_pgoff, NULL)) {
				ret = -ENOMEM;
				goto out;
			}

			vm_stat_account(mm, vma->vm_flags, pages);
			if (vma->vm_flags & VM_LOCKED) {
				mm->locked_vm += pages;
				locked = true;
				new_addr = addr;
			}
			ret = addr;
			goto out;
		}
	}

	/*
         * We weren't able to just expand or shrink the area,
         * we need to create a new one and move it..
         */
	ret = -ENOMEM;
	if (flags & MREMAP_MAYMOVE) {
		unsigned long map_flags = 0;
		if (vma->vm_flags & VM_MAYSHARE)
			map_flags |= MAP_SHARED;

		new_addr = get_unmapped_area(vma->vm_file, 0, new_len,
					vma->vm_pgoff +
					((addr - vma->vm_start) >> PAGE_SHIFT),
					map_flags);
		if (offset_in_page(new_addr)) {
			ret = new_addr;
			goto out;
		}

		ret = move_vma(vma, addr, old_len, new_len, new_addr,
			       &locked, &uf, &uf_unmap);
	}
out:
	if (offset_in_page(ret)) {
		vm_unacct_memory(charged);
		locked = 0;
	}
	up_write(&current->mm->mmap_sem);
	if (locked && new_len > old_len)
		mm_populate(new_addr + old_len, new_len - old_len);
	mremap_userfaultfd_complete(&uf, addr, new_addr, old_len);
	userfaultfd_unmap_complete(mm, &uf_unmap);
	return ret;
}
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5
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1.74%
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0.87%
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1.19%
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21
0.75%
1
0.87%
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0.65%
1
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17
0.61%
1
0.87%
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16
0.58%
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2.61%
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1.74%
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0.43%
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0.40%
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1
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0.11%
1
0.87%
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3
0.11%
1
0.87%
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0.11%
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0.11%
1
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1
0.04%
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1
0.04%
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1
0.04%
1
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Davidlohr Bueso A
1
0.04%
1
0.87%
Total
2782
100.00%
115
100.00%
Directory: mm

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