struct swap_list_t swap_list = {-1, -1};
-struct swap_info_struct swap_info[MAX_SWAPFILES];
+static struct swap_info_struct swap_info[MAX_SWAPFILES];
static DEFINE_MUTEX(swapon_mutex);
last_in_cluster = offset + SWAPFILE_CLUSTER;
else if (offset == last_in_cluster) {
spin_lock(&swap_lock);
- si->cluster_next = offset-SWAPFILE_CLUSTER-1;
+ si->cluster_next = offset-SWAPFILE_CLUSTER+1;
goto cluster;
}
if (unlikely(--latency_ration < 0)) {
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)
- page = find_trylock_page(&swapper_space, entry.val);
+ if (swap_entry_free(p, swp_offset(entry)) == 1) {
+ page = find_get_page(&swapper_space, entry.val);
+ if (page && unlikely(TestSetPageLocked(page))) {
+ page_cache_release(page);
+ page = NULL;
+ }
+ }
spin_unlock(&swap_lock);
}
if (page) {
int one_user;
BUG_ON(PagePrivate(page));
- page_cache_get(page);
one_user = (page_count(page) == 2);
/* Only cache user (+us), or swap space full? Free it! */
- if (!PageWriteback(page) && (one_user || vm_swap_full())) {
+ /* Also recheck PageSwapCache after page is locked (above) */
+ if (PageSwapCache(page) && !PageWriteback(page) &&
+ (one_user || vm_swap_full())) {
delete_from_swap_cache(page);
SetPageDirty(page);
}
}
}
+#ifdef CONFIG_SOFTWARE_SUSPEND
+/*
+ * Find the swap type that corresponds to given device (if any)
+ *
+ * This is needed for software suspend and is done in such a way that inode
+ * aliasing is allowed.
+ */
+int swap_type_of(dev_t device)
+{
+ int i;
+
+ spin_lock(&swap_lock);
+ for (i = 0; i < nr_swapfiles; i++) {
+ struct inode *inode;
+
+ if (!(swap_info[i].flags & SWP_WRITEOK))
+ continue;
+ if (!device) {
+ spin_unlock(&swap_lock);
+ return i;
+ }
+ inode = swap_info->swap_file->f_dentry->d_inode;
+ if (S_ISBLK(inode->i_mode) &&
+ device == MKDEV(imajor(inode), iminor(inode))) {
+ spin_unlock(&swap_lock);
+ return i;
+ }
+ }
+ spin_unlock(&swap_lock);
+ return -ENODEV;
+}
+
+/*
+ * Return either the total number of swap pages of given type, or the number
+ * of free pages of that type (depending on @free)
+ *
+ * This is needed for software suspend
+ */
+unsigned int count_swap_pages(int type, int free)
+{
+ unsigned int n = 0;
+
+ if (type < nr_swapfiles) {
+ spin_lock(&swap_lock);
+ if (swap_info[type].flags & SWP_WRITEOK) {
+ n = swap_info[type].pages;
+ if (free)
+ n -= swap_info[type].inuse_pages;
+ }
+ spin_unlock(&swap_lock);
+ }
+ return n;
+}
+#endif
+
/*
* No need to decide whether this PTE shares the swap entry with others,
* just let do_wp_page work it out if a write is requested later - to
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.
*/
swap_map = &si->swap_map[i];
entry = swp_entry(type, i);
-again:
page = read_swap_cache_async(entry, NULL, 0);
if (!page) {
/*
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);
/*
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;
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;
}
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;
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;
projects / karo-tx-linux.git / blobdiff