summaryrefslogtreecommitdiff
path: root/mm/mlock.c
diff options
context:
space:
mode:
authorMatthew Wilcox (Oracle) <willy@infradead.org>2022-09-06 22:49:02 +0300
committerAndrew Morton <akpm@linux-foundation.org>2022-09-27 05:46:24 +0300
commit33108b05f39b78137c38c677b7a2d0fb7defed14 (patch)
tree5b62b4809e3c65c01a0101f2e0e47b81d930cd1a /mm/mlock.c
parent66850be55e8e5f371db2c091751a932a656c5f4d (diff)
downloadlinux-33108b05f39b78137c38c677b7a2d0fb7defed14.tar.xz
mm/mlock: use vma iterator and maple state instead of vma linked list
Handle overflow checking in count_mm_mlocked_page_nr() differently. Link: https://lkml.kernel.org/r/20220906194824.2110408-58-Liam.Howlett@oracle.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Tested-by: Yu Zhao <yuzhao@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: SeongJae Park <sj@kernel.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/mlock.c')
-rw-r--r--mm/mlock.c35
1 files changed, 19 insertions, 16 deletions
diff --git a/mm/mlock.c b/mm/mlock.c
index b14e929084cc..43d19a1f28eb 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -471,6 +471,7 @@ static int apply_vma_lock_flags(unsigned long start, size_t len,
unsigned long nstart, end, tmp;
struct vm_area_struct *vma, *prev;
int error;
+ MA_STATE(mas, &current->mm->mm_mt, start, start);
VM_BUG_ON(offset_in_page(start));
VM_BUG_ON(len != PAGE_ALIGN(len));
@@ -479,13 +480,14 @@ static int apply_vma_lock_flags(unsigned long start, size_t len,
return -EINVAL;
if (end == start)
return 0;
- vma = find_vma(current->mm, start);
- if (!vma || vma->vm_start > start)
+ vma = mas_walk(&mas);
+ if (!vma)
return -ENOMEM;
- prev = vma->vm_prev;
if (start > vma->vm_start)
prev = vma;
+ else
+ prev = mas_prev(&mas, 0);
for (nstart = start ; ; ) {
vm_flags_t newflags = vma->vm_flags & VM_LOCKED_CLEAR_MASK;
@@ -505,7 +507,7 @@ static int apply_vma_lock_flags(unsigned long start, size_t len,
if (nstart >= end)
break;
- vma = prev->vm_next;
+ vma = find_vma(prev->vm_mm, prev->vm_end);
if (!vma || vma->vm_start != nstart) {
error = -ENOMEM;
break;
@@ -526,24 +528,23 @@ static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm,
{
struct vm_area_struct *vma;
unsigned long count = 0;
+ unsigned long end;
+ VMA_ITERATOR(vmi, mm, start);
if (mm == NULL)
mm = current->mm;
- vma = find_vma(mm, start);
- if (vma == NULL)
- return 0;
-
- for (; vma ; vma = vma->vm_next) {
- if (start >= vma->vm_end)
- continue;
- if (start + len <= vma->vm_start)
- break;
+ /* Don't overflow past ULONG_MAX */
+ if (unlikely(ULONG_MAX - len < start))
+ end = ULONG_MAX;
+ else
+ end = start + len;
+ for_each_vma_range(vmi, vma, end) {
if (vma->vm_flags & VM_LOCKED) {
if (start > vma->vm_start)
count -= (start - vma->vm_start);
- if (start + len < vma->vm_end) {
- count += start + len - vma->vm_start;
+ if (end < vma->vm_end) {
+ count += end - vma->vm_start;
break;
}
count += vma->vm_end - vma->vm_start;
@@ -659,6 +660,7 @@ SYSCALL_DEFINE2(munlock, unsigned long, start, size_t, len)
*/
static int apply_mlockall_flags(int flags)
{
+ MA_STATE(mas, &current->mm->mm_mt, 0, 0);
struct vm_area_struct *vma, *prev = NULL;
vm_flags_t to_add = 0;
@@ -679,7 +681,7 @@ static int apply_mlockall_flags(int flags)
to_add |= VM_LOCKONFAULT;
}
- for (vma = current->mm->mmap; vma ; vma = prev->vm_next) {
+ mas_for_each(&mas, vma, ULONG_MAX) {
vm_flags_t newflags;
newflags = vma->vm_flags & VM_LOCKED_CLEAR_MASK;
@@ -687,6 +689,7 @@ static int apply_mlockall_flags(int flags)
/* Ignore errors */
mlock_fixup(vma, &prev, vma->vm_start, vma->vm_end, newflags);
+ mas_pause(&mas);
cond_resched();
}
out: