summaryrefslogtreecommitdiff
path: root/mm/mremap.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/mremap.c')
-rw-r--r--mm/mremap.c27
1 files changed, 9 insertions, 18 deletions
diff --git a/mm/mremap.c b/mm/mremap.c
index 616facc3d28a..8de77b632a20 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -28,9 +28,6 @@ static pmd_t *get_old_pmd(struct mm_struct *mm, unsigned long addr)
pud_t *pud;
pmd_t *pmd;
- /*
- * We don't need page_table_lock: we have mmap_sem exclusively.
- */
pgd = pgd_offset(mm, addr);
if (pgd_none_or_clear_bad(pgd))
return NULL;
@@ -50,25 +47,20 @@ static pmd_t *alloc_new_pmd(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pud_t *pud;
- pmd_t *pmd = NULL;
+ pmd_t *pmd;
- /*
- * We do need page_table_lock: because allocators expect that.
- */
- spin_lock(&mm->page_table_lock);
pgd = pgd_offset(mm, addr);
pud = pud_alloc(mm, pgd, addr);
if (!pud)
- goto out;
+ return NULL;
pmd = pmd_alloc(mm, pud, addr);
if (!pmd)
- goto out;
+ return NULL;
if (!pmd_present(*pmd) && __pte_alloc(mm, pmd, addr))
- pmd = NULL;
-out:
- spin_unlock(&mm->page_table_lock);
+ return NULL;
+
return pmd;
}
@@ -80,6 +72,7 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
struct address_space *mapping = NULL;
struct mm_struct *mm = vma->vm_mm;
pte_t *old_pte, *new_pte, pte;
+ spinlock_t *old_ptl;
if (vma->vm_file) {
/*
@@ -95,9 +88,8 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
new_vma->vm_truncate_count = 0;
}
- spin_lock(&mm->page_table_lock);
- old_pte = pte_offset_map(old_pmd, old_addr);
- new_pte = pte_offset_map_nested(new_pmd, new_addr);
+ old_pte = pte_offset_map_lock(mm, old_pmd, old_addr, &old_ptl);
+ new_pte = pte_offset_map_nested(new_pmd, new_addr);
for (; old_addr < old_end; old_pte++, old_addr += PAGE_SIZE,
new_pte++, new_addr += PAGE_SIZE) {
@@ -110,8 +102,7 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
}
pte_unmap_nested(new_pte - 1);
- pte_unmap(old_pte - 1);
- spin_unlock(&mm->page_table_lock);
+ pte_unmap_unlock(old_pte - 1, old_ptl);
if (mapping)
spin_unlock(&mapping->i_mmap_lock);
}