diff --git a/mm/internal.h b/mm/internal.h
index 397183c8fe47..3a2e973138d3 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -331,27 +331,52 @@ static inline void mlock_migrate_page(struct page *newpage, struct page *page)
extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
/*
- * At what user virtual address is page expected in @vma?
+ * At what user virtual address is page expected in vma?
+ * Returns -EFAULT if all of the page is outside the range of vma.
+ * If page is a compound head, the entire compound page is considered.
*/
-static inline unsigned long
-__vma_address(struct page *page, struct vm_area_struct *vma)
-{
- pgoff_t pgoff = page_to_pgoff(page);
- return vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
-}
-
static inline unsigned long
vma_address(struct page *page, struct vm_area_struct *vma)
{
- unsigned long start, end;
+ pgoff_t pgoff;
+ unsigned long address;
- start = __vma_address(page, vma);
- end = start + PAGE_SIZE * (hpage_nr_pages(page) - 1);
+ VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */
+ pgoff = page_to_pgoff(page);
+ if (pgoff >= vma->vm_pgoff) {
+ address = vma->vm_start +
+ ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+ /* Check for address beyond vma (or wrapped through 0?) */
+ if (address < vma->vm_start || address >= vma->vm_end)
+ address = -EFAULT;
+ } else if (PageHead(page) &&
+ pgoff + (1UL << compound_order(page)) - 1 >= vma->vm_pgoff) {
+ /* Test above avoids possibility of wrap to 0 on 32-bit */
+ address = vma->vm_start;
+ } else {
+ address = -EFAULT;
+ }
+ return address;
+}
- /* page should be within @vma mapping range */
- VM_BUG_ON_VMA(end < vma->vm_start || start >= vma->vm_end, vma);
+/*
+ * Then at what user virtual address will none of the page be found in vma?
+ * Assumes that vma_address() already returned a good starting address.
+ * If page is a compound head, the entire compound page is considered.
+ */
+static inline unsigned long
+vma_address_end(struct page *page, struct vm_area_struct *vma)
+{
+ pgoff_t pgoff;
+ unsigned long address;
- return max(start, vma->vm_start);
+ VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */
+ pgoff = page_to_pgoff(page) + (1UL << compound_order(page));
+ address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+ /* Check for address beyond vma (or wrapped through 0?) */
+ if (address < vma->vm_start || address > vma->vm_end)
+ address = vma->vm_end;
+ return address;
}
#else /* !CONFIG_MMU */
diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c
index 08e283ad4660..bb7488e86bea 100644
--- a/mm/page_vma_mapped.c
+++ b/mm/page_vma_mapped.c
@@ -224,18 +224,18 @@ restart:
if (!map_pte(pvmw))
goto next_pte;
while (1) {
+ unsigned long end;
+
if (check_pte(pvmw))
return true;
next_pte:
/* Seek to next pte only makes sense for THP */
if (!PageTransHuge(pvmw->page) || PageHuge(pvmw->page))
return not_found(pvmw);
+ end = vma_address_end(pvmw->page, pvmw->vma);
do {
pvmw->address += PAGE_SIZE;
- if (pvmw->address >= pvmw->vma->vm_end ||
- pvmw->address >=
- __vma_address(pvmw->page, pvmw->vma) +
- hpage_nr_pages(pvmw->page) * PAGE_SIZE)
+ if (pvmw->address >= end)
return not_found(pvmw);
/* Did we cross page table boundary? */
if (pvmw->address % PMD_SIZE == 0) {
@@ -273,14 +273,10 @@ int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma)
.vma = vma,
.flags = PVMW_SYNC,
};
- unsigned long start, end;
- start = __vma_address(page, vma);
- end = start + PAGE_SIZE * (hpage_nr_pages(page) - 1);
-
- if (unlikely(end < vma->vm_start || start >= vma->vm_end))
+ pvmw.address = vma_address(page, vma);
+ if (pvmw.address == -EFAULT)
return 0;
- pvmw.address = max(start, vma->vm_start);
if (!page_vma_mapped_walk(&pvmw))
return 0;
page_vma_mapped_walk_done(&pvmw);
diff --git a/mm/rmap.c b/mm/rmap.c
index 5df055654e63..ff56c460af53 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -686,7 +686,6 @@ static bool should_defer_flush(struct mm_struct *mm, enum ttu_flags flags)
*/
unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma)
{
- unsigned long address;
if (PageAnon(page)) {
struct anon_vma *page__anon_vma = page_anon_vma(page);
/*
@@ -701,10 +700,8 @@ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma)
return -EFAULT;
} else
return -EFAULT;
- address = __vma_address(page, vma);
- if (unlikely(address < vma->vm_start || address >= vma->vm_end))
- return -EFAULT;
- return address;
+
+ return vma_address(page, vma);
}
pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address)
@@ -896,7 +893,7 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma,
* We have to assume the worse case ie pmd for invalidation. Note that
* the page can not be free from this function.
*/
- end = min(vma->vm_end, start + (PAGE_SIZE << compound_order(page)));
+ end = vma_address_end(page, vma);
mmu_notifier_invalidate_range_start(vma->vm_mm, start, end);
while (page_vma_mapped_walk(&pvmw)) {
@@ -1378,7 +1375,8 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
* Note that the page can not be free in this function as call of
* try_to_unmap() must hold a reference on the page.
*/
- end = min(vma->vm_end, start + (PAGE_SIZE << compound_order(page)));
+ end = PageKsm(page) ?
+ address + PAGE_SIZE : vma_address_end(page, vma);
if (PageHuge(page)) {
/*
* If sharing is possible, start and end will be adjusted
@@ -1835,6 +1833,7 @@ static void rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc,
struct vm_area_struct *vma = avc->vma;
unsigned long address = vma_address(page, vma);
+ VM_BUG_ON_VMA(address == -EFAULT, vma);
cond_resched();
if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
@@ -1889,6 +1888,7 @@ static void rmap_walk_file(struct page *page, struct rmap_walk_control *rwc,
pgoff_start, pgoff_end) {
unsigned long address = vma_address(page, vma);
+ VM_BUG_ON_VMA(address == -EFAULT, vma);
cond_resched();
if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))