summaryrefslogtreecommitdiffstats
path: root/mm/pgtable-generic.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/pgtable-generic.c')
-rw-r--r--mm/pgtable-generic.c58
1 files changed, 57 insertions, 1 deletions
diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
index d2fc52bffafc..4d454953046f 100644
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -10,6 +10,8 @@
#include <linux/pagemap.h>
#include <linux/hugetlb.h>
#include <linux/pgtable.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
#include <linux/mm_inline.h>
#include <asm/tlb.h>
@@ -66,7 +68,7 @@ int ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep,
pte_t entry, int dirty)
{
- int changed = !pte_same(*ptep, entry);
+ int changed = !pte_same(ptep_get(ptep), entry);
if (changed) {
set_pte_at(vma->vm_mm, address, ptep, entry);
flush_tlb_fix_spurious_fault(vma, address, ptep);
@@ -229,3 +231,57 @@ pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address,
}
#endif
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
+pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp)
+{
+ pmd_t pmdval;
+
+ /* rcu_read_lock() to be added later */
+ pmdval = pmdp_get_lockless(pmd);
+ if (pmdvalp)
+ *pmdvalp = pmdval;
+ if (unlikely(pmd_none(pmdval) || is_pmd_migration_entry(pmdval)))
+ goto nomap;
+ if (unlikely(pmd_trans_huge(pmdval) || pmd_devmap(pmdval)))
+ goto nomap;
+ if (unlikely(pmd_bad(pmdval))) {
+ pmd_clear_bad(pmd);
+ goto nomap;
+ }
+ return __pte_map(&pmdval, addr);
+nomap:
+ /* rcu_read_unlock() to be added later */
+ return NULL;
+}
+
+pte_t *pte_offset_map_nolock(struct mm_struct *mm, pmd_t *pmd,
+ unsigned long addr, spinlock_t **ptlp)
+{
+ pmd_t pmdval;
+ pte_t *pte;
+
+ pte = __pte_offset_map(pmd, addr, &pmdval);
+ if (likely(pte))
+ *ptlp = pte_lockptr(mm, &pmdval);
+ return pte;
+}
+
+pte_t *__pte_offset_map_lock(struct mm_struct *mm, pmd_t *pmd,
+ unsigned long addr, spinlock_t **ptlp)
+{
+ spinlock_t *ptl;
+ pmd_t pmdval;
+ pte_t *pte;
+again:
+ pte = __pte_offset_map(pmd, addr, &pmdval);
+ if (unlikely(!pte))
+ return pte;
+ ptl = pte_lockptr(mm, &pmdval);
+ spin_lock(ptl);
+ if (likely(pmd_same(pmdval, pmdp_get_lockless(pmd)))) {
+ *ptlp = ptl;
+ return pte;
+ }
+ pte_unmap_unlock(pte, ptl);
+ goto again;
+}