#include <linux/pagemap.h>
#include <linux/migrate.h>
#include <linux/hashtable.h>
+#include <linux/userfaultfd_k.h>
#include <asm/tlb.h>
#include <asm/pgalloc.h>
static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
struct vm_area_struct *vma,
- unsigned long haddr, pmd_t *pmd,
- struct page *page, gfp_t gfp)
+ unsigned long address, pmd_t *pmd,
+ struct page *page, gfp_t gfp,
+ unsigned int flags)
{
struct mem_cgroup *memcg;
pgtable_t pgtable;
spinlock_t *ptl;
+ unsigned long haddr = address & HPAGE_PMD_MASK;
VM_BUG_ON_PAGE(!PageCompound(page), page);
- if (mem_cgroup_try_charge(page, mm, gfp, &memcg))
- return VM_FAULT_OOM;
+ if (mem_cgroup_try_charge(page, mm, gfp, &memcg)) {
+ put_page(page);
+ count_vm_event(THP_FAULT_FALLBACK);
+ return VM_FAULT_FALLBACK;
+ }
pgtable = pte_alloc_one(mm, haddr);
if (unlikely(!pgtable)) {
mem_cgroup_cancel_charge(page, memcg);
+ put_page(page);
return VM_FAULT_OOM;
}
pte_free(mm, pgtable);
} else {
pmd_t entry;
+
+ /* Deliver the page fault to userland */
+ if (userfaultfd_missing(vma)) {
+ int ret;
+
+ spin_unlock(ptl);
+ mem_cgroup_cancel_charge(page, memcg);
+ put_page(page);
+ pte_free(mm, pgtable);
+ ret = handle_userfault(vma, address, flags,
+ VM_UFFD_MISSING);
+ VM_BUG_ON(ret & VM_FAULT_FALLBACK);
+ return ret;
+ }
+
entry = mk_huge_pmd(page, vma->vm_page_prot);
entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
page_add_new_anon_rmap(page, vma, haddr);
add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
atomic_long_inc(&mm->nr_ptes);
spin_unlock(ptl);
+ count_vm_event(THP_FAULT_ALLOC);
}
return 0;
}
/* Caller must hold page table lock. */
-static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
+static void set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
struct vm_area_struct *vma, unsigned long haddr, pmd_t *pmd,
struct page *zero_page)
{
pmd_t entry;
- if (!pmd_none(*pmd))
- return false;
entry = mk_pmd(zero_page, vma->vm_page_prot);
entry = pmd_mkhuge(entry);
pgtable_trans_huge_deposit(mm, pmd, pgtable);
set_pmd_at(mm, haddr, pmd, entry);
atomic_long_inc(&mm->nr_ptes);
- return true;
}
int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
pgtable_t pgtable;
struct page *zero_page;
bool set;
+ int ret;
pgtable = pte_alloc_one(mm, haddr);
if (unlikely(!pgtable))
return VM_FAULT_OOM;
return VM_FAULT_FALLBACK;
}
ptl = pmd_lock(mm, pmd);
- set = set_huge_zero_page(pgtable, mm, vma, haddr, pmd,
- zero_page);
- spin_unlock(ptl);
+ ret = 0;
+ set = false;
+ if (pmd_none(*pmd)) {
+ if (userfaultfd_missing(vma)) {
+ spin_unlock(ptl);
+ ret = handle_userfault(vma, address, flags,
+ VM_UFFD_MISSING);
+ VM_BUG_ON(ret & VM_FAULT_FALLBACK);
+ } else {
+ set_huge_zero_page(pgtable, mm, vma,
+ haddr, pmd,
+ zero_page);
+ spin_unlock(ptl);
+ set = true;
+ }
+ } else
+ spin_unlock(ptl);
if (!set) {
pte_free(mm, pgtable);
put_huge_zero_page();
}
- return 0;
+ return ret;
}
gfp = alloc_hugepage_gfpmask(transparent_hugepage_defrag(vma), 0);
page = alloc_hugepage_vma(gfp, vma, haddr, HPAGE_PMD_ORDER);
count_vm_event(THP_FAULT_FALLBACK);
return VM_FAULT_FALLBACK;
}
- if (unlikely(__do_huge_pmd_anonymous_page(mm, vma, haddr, pmd, page, gfp))) {
- put_page(page);
- count_vm_event(THP_FAULT_FALLBACK);
- return VM_FAULT_FALLBACK;
- }
-
- count_vm_event(THP_FAULT_ALLOC);
- return 0;
+ return __do_huge_pmd_anonymous_page(mm, vma, address, pmd, page, gfp,
+ flags);
}
int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
*/
if (is_huge_zero_pmd(pmd)) {
struct page *zero_page;
- bool set;
/*
* get_huge_zero_page() will never allocate a new page here,
* since we already have a zero page to copy. It just takes a
* reference.
*/
zero_page = get_huge_zero_page();
- set = set_huge_zero_page(pgtable, dst_mm, vma, addr, dst_pmd,
+ set_huge_zero_page(pgtable, dst_mm, vma, addr, dst_pmd,
zero_page);
- BUG_ON(!set); /* unexpected !pmd_none(dst_pmd) */
ret = 0;
goto out_unlock;
}
/* after clearing PageTail the gup refcount can be released */
smp_mb__after_atomic();
- /*
- * retain hwpoison flag of the poisoned tail page:
- * fix for the unsuitable process killed on Guest Machine(KVM)
- * by the memory-failure.
- */
- page_tail->flags &= ~PAGE_FLAGS_CHECK_AT_PREP | __PG_HWPOISON;
+ page_tail->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
page_tail->flags |= (page->flags &
((1L << PG_referenced) |
(1L << PG_swapbacked) |
_pte++, address += PAGE_SIZE) {
pte_t pteval = *_pte;
if (pte_none(pteval) || is_zero_pfn(pte_pfn(pteval))) {
- if (++none_or_zero <= khugepaged_max_ptes_none)
+ if (!userfaultfd_armed(vma) &&
+ ++none_or_zero <= khugepaged_max_ptes_none)
continue;
else
goto out;
_pte++, _address += PAGE_SIZE) {
pte_t pteval = *_pte;
if (pte_none(pteval) || is_zero_pfn(pte_pfn(pteval))) {
- if (++none_or_zero <= khugepaged_max_ptes_none)
+ if (!userfaultfd_armed(vma) &&
+ ++none_or_zero <= khugepaged_max_ptes_none)
continue;
else
goto out_unmap;
projects / firefly-linux-kernel-4.4.55.git / blobdiff