/* Forward declaration */
static int hugetlb_acct_memory(struct hstate *h, long delta);
+static void hugetlb_unshare_pmds(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end);
static inline bool subpool_is_free(struct hugepage_subpool *spool)
{
{
if (addr & ~(huge_page_mask(hstate_vma(vma))))
return -EINVAL;
+
+ /*
+ * PMD sharing is only possible for PUD_SIZE-aligned address ranges
+ * in HugeTLB VMAs. If we will lose PUD_SIZE alignment due to this
+ * split, unshare PMDs in the PUD_SIZE interval surrounding addr now.
+ */
+ if (addr & ~PUD_MASK) {
+ /*
+ * hugetlb_vm_op_split is called right before we attempt to
+ * split the VMA. We will need to unshare PMDs in the old and
+ * new VMAs, so let's unshare before we split.
+ */
+ unsigned long floor = addr & PUD_MASK;
+ unsigned long ceil = floor + PUD_SIZE;
+
+ if (floor >= vma->vm_start && ceil <= vma->vm_end)
+ hugetlb_unshare_pmds(vma, floor, ceil);
+ }
+
return 0;
}
ptl = huge_pte_lockptr(h, dst_mm, dst_pte);
spin_lock(ptl);
+ ret = -EIO;
+ if (PageHWPoison(page))
+ goto out_release_unlock;
+
/*
* Recheck the i_size after holding PT lock to make sure not
* to leave any page mapped (as page_mapped()) beyond the end
}
}
-/*
- * This function will unconditionally remove all the shared pmd pgtable entries
- * within the specific vma for a hugetlbfs memory range.
- */
-void hugetlb_unshare_all_pmds(struct vm_area_struct *vma)
+static void hugetlb_unshare_pmds(struct vm_area_struct *vma,
+ unsigned long start,
+ unsigned long end)
{
struct hstate *h = hstate_vma(vma);
unsigned long sz = huge_page_size(h);
struct mm_struct *mm = vma->vm_mm;
struct mmu_notifier_range range;
- unsigned long address, start, end;
+ unsigned long address;
spinlock_t *ptl;
pte_t *ptep;
if (!(vma->vm_flags & VM_MAYSHARE))
return;
- start = ALIGN(vma->vm_start, PUD_SIZE);
- end = ALIGN_DOWN(vma->vm_end, PUD_SIZE);
-
if (start >= end)
return;
mmu_notifier_invalidate_range_end(&range);
}
+/*
+ * This function will unconditionally remove all the shared pmd pgtable entries
+ * within the specific vma for a hugetlbfs memory range.
+ */
+void hugetlb_unshare_all_pmds(struct vm_area_struct *vma)
+{
+ hugetlb_unshare_pmds(vma, ALIGN(vma->vm_start, PUD_SIZE),
+ ALIGN_DOWN(vma->vm_end, PUD_SIZE));
+}
+
#ifdef CONFIG_CMA
static bool cma_reserve_called __initdata;