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Diffstat (limited to 'mm/mlock.c')
-rw-r--r--mm/mlock.c81
1 files changed, 64 insertions, 17 deletions
diff --git a/mm/mlock.c b/mm/mlock.c
index 4f31864..67b3dd8 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -377,18 +377,10 @@ static int mlock_fixup(struct vm_area_struct *vma, struct vm_area_struct **prev,
int ret = 0;
int lock = newflags & VM_LOCKED;
- if (newflags == vma->vm_flags ||
- (vma->vm_flags & (VM_IO | VM_PFNMAP)))
+ if (newflags == vma->vm_flags || (vma->vm_flags & VM_SPECIAL) ||
+ is_vm_hugetlb_page(vma) || vma == get_gate_vma(current))
goto out; /* don't set VM_LOCKED, don't count */
- if ((vma->vm_flags & (VM_DONTEXPAND | VM_RESERVED)) ||
- is_vm_hugetlb_page(vma) ||
- vma == get_gate_vma(current)) {
- if (lock)
- make_pages_present(start, end);
- goto out; /* don't set VM_LOCKED, don't count */
- }
-
pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
*prev = vma_merge(mm, *prev, start, end, newflags, vma->anon_vma,
vma->vm_file, pgoff, vma_policy(vma));
@@ -424,14 +416,10 @@ success:
* set VM_LOCKED, __mlock_vma_pages_range will bring it back.
*/
- if (lock) {
+ if (lock)
vma->vm_flags = newflags;
- ret = __mlock_vma_pages_range(vma, start, end);
- if (ret < 0)
- ret = __mlock_posix_error_return(ret);
- } else {
+ else
munlock_vma_pages_range(vma, start, end);
- }
out:
*prev = vma;
@@ -444,7 +432,8 @@ static int do_mlock(unsigned long start, size_t len, int on)
struct vm_area_struct * vma, * prev;
int error;
- len = PAGE_ALIGN(len);
+ VM_BUG_ON(start & ~PAGE_MASK);
+ VM_BUG_ON(len != PAGE_ALIGN(len));
end = start + len;
if (end < start)
return -EINVAL;
@@ -487,6 +476,58 @@ static int do_mlock(unsigned long start, size_t len, int on)
return error;
}
+static int do_mlock_pages(unsigned long start, size_t len, int ignore_errors)
+{
+ struct mm_struct *mm = current->mm;
+ unsigned long end, nstart, nend;
+ struct vm_area_struct *vma = NULL;
+ int ret = 0;
+
+ VM_BUG_ON(start & ~PAGE_MASK);
+ VM_BUG_ON(len != PAGE_ALIGN(len));
+ end = start + len;
+
+ down_read(&mm->mmap_sem);
+ for (nstart = start; nstart < end; nstart = nend) {
+ /*
+ * We want to fault in pages for [nstart; end) address range.
+ * Find first corresponding VMA.
+ */
+ if (!vma)
+ vma = find_vma(mm, nstart);
+ else
+ vma = vma->vm_next;
+ if (!vma || vma->vm_start >= end)
+ break;
+ /*
+ * Set [nstart; nend) to intersection of desired address
+ * range with the first VMA. Also, skip undesirable VMA types.
+ */
+ nend = min(end, vma->vm_end);
+ if (vma->vm_flags & (VM_IO | VM_PFNMAP))
+ continue;
+ if (nstart < vma->vm_start)
+ nstart = vma->vm_start;
+ /*
+ * Now fault in a range of pages within the first VMA.
+ */
+ if (vma->vm_flags & VM_LOCKED) {
+ ret = __mlock_vma_pages_range(vma, nstart, nend);
+ if (ret < 0 && ignore_errors) {
+ ret = 0;
+ continue; /* continue at next VMA */
+ }
+ if (ret) {
+ ret = __mlock_posix_error_return(ret);
+ break;
+ }
+ } else
+ make_pages_present(nstart, nend);
+ }
+ up_read(&mm->mmap_sem);
+ return ret; /* 0 or negative error code */
+}
+
SYSCALL_DEFINE2(mlock, unsigned long, start, size_t, len)
{
unsigned long locked;
@@ -512,6 +553,8 @@ SYSCALL_DEFINE2(mlock, unsigned long, start, size_t, len)
if ((locked <= lock_limit) || capable(CAP_IPC_LOCK))
error = do_mlock(start, len, 1);
up_write(&current->mm->mmap_sem);
+ if (!error)
+ error = do_mlock_pages(start, len, 0);
return error;
}
@@ -576,6 +619,10 @@ SYSCALL_DEFINE1(mlockall, int, flags)
capable(CAP_IPC_LOCK))
ret = do_mlockall(flags);
up_write(&current->mm->mmap_sem);
+ if (!ret && (flags & MCL_CURRENT)) {
+ /* Ignore errors */
+ do_mlock_pages(0, TASK_SIZE, 1);
+ }
out:
return ret;
}
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