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Diffstat (limited to 'mm/mremap.c')
-rw-r--r--mm/mremap.c36
1 files changed, 13 insertions, 23 deletions
diff --git a/mm/mremap.c b/mm/mremap.c
index 975a14c4a24e..90ff09c09e84 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -515,11 +515,19 @@ static unsigned long move_vma(struct vm_area_struct *vma,
if (err)
return err;
+ if (unlikely(flags & MREMAP_DONTUNMAP && vm_flags & VM_ACCOUNT)) {
+ if (security_vm_enough_memory_mm(mm, new_len >> PAGE_SHIFT))
+ return -ENOMEM;
+ }
+
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)
+ if (!new_vma) {
+ if (unlikely(flags & MREMAP_DONTUNMAP && vm_flags & VM_ACCOUNT))
+ vm_unacct_memory(new_len >> PAGE_SHIFT);
return -ENOMEM;
+ }
moved_len = move_page_tables(vma, old_addr, new_vma, new_addr, old_len,
need_rmap_locks);
@@ -548,7 +556,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
}
/* Conceal VM_ACCOUNT so old reservation is not undone */
- if (vm_flags & VM_ACCOUNT) {
+ if (vm_flags & VM_ACCOUNT && !(flags & MREMAP_DONTUNMAP)) {
vma->vm_flags &= ~VM_ACCOUNT;
excess = vma->vm_end - vma->vm_start - old_len;
if (old_addr > vma->vm_start &&
@@ -573,34 +581,16 @@ static unsigned long move_vma(struct vm_area_struct *vma,
untrack_pfn_moved(vma);
if (unlikely(!err && (flags & MREMAP_DONTUNMAP))) {
- if (vm_flags & VM_ACCOUNT) {
- /* Always put back VM_ACCOUNT since we won't unmap */
- vma->vm_flags |= VM_ACCOUNT;
-
- vm_acct_memory(new_len >> PAGE_SHIFT);
- }
-
- /*
- * VMAs can actually be merged back together in copy_vma
- * calling merge_vma. This can happen with anonymous vmas
- * which have not yet been faulted, so if we were to consider
- * this VMA split we'll end up adding VM_ACCOUNT on the
- * next VMA, which is completely unrelated if this VMA
- * was re-merged.
- */
- if (split && new_vma == vma)
- split = 0;
-
/* We always clear VM_LOCKED[ONFAULT] on the old vma */
vma->vm_flags &= VM_LOCKED_CLEAR_MASK;
/* Because we won't unmap we don't need to touch locked_vm */
- goto out;
+ return new_addr;
}
if (do_munmap(mm, old_addr, old_len, uf_unmap) < 0) {
/* OOM: unable to split vma, just get accounts right */
- if (vm_flags & VM_ACCOUNT)
+ if (vm_flags & VM_ACCOUNT && !(flags & MREMAP_DONTUNMAP))
vm_acct_memory(new_len >> PAGE_SHIFT);
excess = 0;
}
@@ -609,7 +599,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
mm->locked_vm += new_len >> PAGE_SHIFT;
*locked = true;
}
-out:
+
mm->hiwater_vm = hiwater_vm;
/* Restore VM_ACCOUNT if one or two pieces of vma left */