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Diffstat (limited to 'mm/swapfile.c')
-rw-r--r--mm/swapfile.c43
1 files changed, 9 insertions, 34 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c
index e5fd5385f0c..cc367f7e75d 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -395,6 +395,9 @@ void free_swap_and_cache(swp_entry_t entry)
struct swap_info_struct * p;
struct page *page = NULL;
+ if (is_migration_entry(entry))
+ return;
+
p = swap_info_get(entry);
if (p) {
if (swap_entry_free(p, swp_offset(entry)) == 1) {
@@ -615,15 +618,6 @@ static int unuse_mm(struct mm_struct *mm,
return 0;
}
-#ifdef CONFIG_MIGRATION
-int remove_vma_swap(struct vm_area_struct *vma, struct page *page)
-{
- swp_entry_t entry = { .val = page_private(page) };
-
- return unuse_vma(vma, entry, page);
-}
-#endif
-
/*
* Scan swap_map from current position to next entry still in use.
* Recycle to start on reaching the end, returning 0 when empty.
@@ -716,7 +710,6 @@ static int try_to_unuse(unsigned int type)
*/
swap_map = &si->swap_map[i];
entry = swp_entry(type, i);
-again:
page = read_swap_cache_async(entry, NULL, 0);
if (!page) {
/*
@@ -751,12 +744,6 @@ again:
wait_on_page_locked(page);
wait_on_page_writeback(page);
lock_page(page);
- if (!PageSwapCache(page)) {
- /* Page migration has occured */
- unlock_page(page);
- page_cache_release(page);
- goto again;
- }
wait_on_page_writeback(page);
/*
@@ -785,10 +772,8 @@ again:
while (*swap_map > 1 && !retval &&
(p = p->next) != &start_mm->mmlist) {
mm = list_entry(p, struct mm_struct, mmlist);
- if (atomic_inc_return(&mm->mm_users) == 1) {
- atomic_dec(&mm->mm_users);
+ if (!atomic_inc_not_zero(&mm->mm_users))
continue;
- }
spin_unlock(&mmlist_lock);
mmput(prev_mm);
prev_mm = mm;
@@ -1407,19 +1392,7 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags)
if (!(p->flags & SWP_USED))
break;
error = -EPERM;
- /*
- * Test if adding another swap device is possible. There are
- * two limiting factors: 1) the number of bits for the swap
- * type swp_entry_t definition and 2) the number of bits for
- * the swap type in the swap ptes as defined by the different
- * architectures. To honor both limitations a swap entry
- * with swap offset 0 and swap type ~0UL is created, encoded
- * to a swap pte, decoded to a swp_entry_t again and finally
- * the swap type part is extracted. This will mask all bits
- * from the initial ~0UL that can't be encoded in either the
- * swp_entry_t or the architecture definition of a swap pte.
- */
- if (type > swp_type(pte_to_swp_entry(swp_entry_to_pte(swp_entry(~0UL,0))))) {
+ if (type >= MAX_SWAPFILES) {
spin_unlock(&swap_lock);
goto out;
}
@@ -1504,8 +1477,7 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags)
error = -EINVAL;
goto bad_swap;
}
- page = read_cache_page(mapping, 0,
- (filler_t *)mapping->a_ops->readpage, swap_file);
+ page = read_mapping_page(mapping, 0, swap_file);
if (IS_ERR(page)) {
error = PTR_ERR(page);
goto bad_swap;
@@ -1709,6 +1681,9 @@ int swap_duplicate(swp_entry_t entry)
unsigned long offset, type;
int result = 0;
+ if (is_migration_entry(entry))
+ return 1;
+
type = swp_type(entry);
if (type >= nr_swapfiles)
goto bad_file;