#include <linux/shm.h>
#include <linux/mman.h>
#include <linux/swap.h>
+#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/highmem.h>
#include <linux/security.h>
struct address_space *mapping = NULL;
struct mm_struct *mm = vma->vm_mm;
pte_t *old_pte, *new_pte, pte;
- spinlock_t *old_ptl;
+ spinlock_t *old_ptl, *new_ptl;
if (vma->vm_file) {
/*
new_vma->vm_truncate_count = 0;
}
+ /*
+ * We don't have to worry about the ordering of src and dst
+ * pte locks because exclusive mmap_sem prevents deadlock.
+ */
old_pte = pte_offset_map_lock(mm, old_pmd, old_addr, &old_ptl);
new_pte = pte_offset_map_nested(new_pmd, new_addr);
+ new_ptl = pte_lockptr(mm, new_pmd);
+ if (new_ptl != old_ptl)
+ spin_lock_nested(new_ptl, SINGLE_DEPTH_NESTING);
for (; old_addr < old_end; old_pte++, old_addr += PAGE_SIZE,
new_pte++, new_addr += PAGE_SIZE) {
set_pte_at(mm, new_addr, new_pte, pte);
}
+ if (new_ptl != old_ptl)
+ spin_unlock(new_ptl);
pte_unmap_nested(new_pte - 1);
pte_unmap_unlock(old_pte - 1, old_ptl);
if (mapping)
/* We can't remap across vm area boundaries */
if (old_len > vma->vm_end - addr)
goto out;
- if (vma->vm_flags & VM_DONTEXPAND) {
+ if (vma->vm_flags & (VM_DONTEXPAND | VM_PFNMAP)) {
if (new_len > old_len)
goto out;
}