int isolate_movable_page(struct page *page, isolate_mode_t mode)
{
- struct address_space *mapping;
+ const struct movable_operations *mops;
/*
* Avoid burning cycles with pages that are yet under __free_pages(),
if (!PageMovable(page) || PageIsolated(page))
goto out_no_isolated;
- mapping = page_mapping(page);
- VM_BUG_ON_PAGE(!mapping, page);
+ mops = page_movable_ops(page);
+ VM_BUG_ON_PAGE(!mops, page);
- if (!mapping->a_ops->isolate_page(page, mode))
+ if (!mops->isolate_page(page, mode))
goto out_no_isolated;
/* Driver shouldn't use PG_isolated bit of page->flags */
static void putback_movable_page(struct page *page)
{
- struct address_space *mapping;
+ const struct movable_operations *mops = page_movable_ops(page);
- mapping = page_mapping(page);
- mapping->a_ops->putback_page(page);
+ mops->putback_page(page);
ClearPageIsolated(page);
}
}
#endif
-static int expected_page_refs(struct address_space *mapping, struct page *page)
+static int folio_expected_refs(struct address_space *mapping,
+ struct folio *folio)
{
- int expected_count = 1;
+ int refs = 1;
+ if (!mapping)
+ return refs;
- if (mapping)
- expected_count += compound_nr(page) + page_has_private(page);
- return expected_count;
+ refs += folio_nr_pages(folio);
+ if (folio_test_private(folio))
+ refs++;
+
+ return refs;
}
/*
XA_STATE(xas, &mapping->i_pages, folio_index(folio));
struct zone *oldzone, *newzone;
int dirty;
- int expected_count = expected_page_refs(mapping, &folio->page) + extra_count;
+ int expected_count = folio_expected_refs(mapping, folio) + extra_count;
long nr = folio_nr_pages(folio);
if (!mapping) {
* of folio_migrate_mapping().
*/
int migrate_huge_page_move_mapping(struct address_space *mapping,
- struct page *newpage, struct page *page)
+ struct folio *dst, struct folio *src)
{
- XA_STATE(xas, &mapping->i_pages, page_index(page));
+ XA_STATE(xas, &mapping->i_pages, folio_index(src));
int expected_count;
xas_lock_irq(&xas);
- expected_count = 2 + page_has_private(page);
- if (!page_ref_freeze(page, expected_count)) {
+ expected_count = 2 + folio_has_private(src);
+ if (!folio_ref_freeze(src, expected_count)) {
xas_unlock_irq(&xas);
return -EAGAIN;
}
- newpage->index = page->index;
- newpage->mapping = page->mapping;
+ dst->index = src->index;
+ dst->mapping = src->mapping;
- get_page(newpage);
+ folio_get(dst);
- xas_store(&xas, newpage);
+ xas_store(&xas, dst);
- page_ref_unfreeze(page, expected_count - 1);
+ folio_ref_unfreeze(src, expected_count - 1);
xas_unlock_irq(&xas);
* Migration functions
***********************************************************/
-/*
- * Common logic to directly migrate a single LRU page suitable for
- * pages that do not use PagePrivate/PagePrivate2.
+/**
+ * migrate_folio() - Simple folio migration.
+ * @mapping: The address_space containing the folio.
+ * @dst: The folio to migrate the data to.
+ * @src: The folio containing the current data.
+ * @mode: How to migrate the page.
+ *
+ * Common logic to directly migrate a single LRU folio suitable for
+ * folios that do not use PagePrivate/PagePrivate2.
*
- * Pages are locked upon entry and exit.
+ * Folios are locked upon entry and exit.
*/
-int migrate_page(struct address_space *mapping,
- struct page *newpage, struct page *page,
- enum migrate_mode mode)
+int migrate_folio(struct address_space *mapping, struct folio *dst,
+ struct folio *src, enum migrate_mode mode)
{
- struct folio *newfolio = page_folio(newpage);
- struct folio *folio = page_folio(page);
int rc;
- BUG_ON(folio_test_writeback(folio)); /* Writeback must be complete */
+ BUG_ON(folio_test_writeback(src)); /* Writeback must be complete */
- rc = folio_migrate_mapping(mapping, newfolio, folio, 0);
+ rc = folio_migrate_mapping(mapping, dst, src, 0);
if (rc != MIGRATEPAGE_SUCCESS)
return rc;
if (mode != MIGRATE_SYNC_NO_COPY)
- folio_migrate_copy(newfolio, folio);
+ folio_migrate_copy(dst, src);
else
- folio_migrate_flags(newfolio, folio);
+ folio_migrate_flags(dst, src);
return MIGRATEPAGE_SUCCESS;
}
-EXPORT_SYMBOL(migrate_page);
+EXPORT_SYMBOL(migrate_folio);
#ifdef CONFIG_BLOCK
/* Returns true if all buffers are successfully locked */
return true;
}
-static int __buffer_migrate_page(struct address_space *mapping,
- struct page *newpage, struct page *page, enum migrate_mode mode,
+static int __buffer_migrate_folio(struct address_space *mapping,
+ struct folio *dst, struct folio *src, enum migrate_mode mode,
bool check_refs)
{
struct buffer_head *bh, *head;
int rc;
int expected_count;
- if (!page_has_buffers(page))
- return migrate_page(mapping, newpage, page, mode);
+ head = folio_buffers(src);
+ if (!head)
+ return migrate_folio(mapping, dst, src, mode);
/* Check whether page does not have extra refs before we do more work */
- expected_count = expected_page_refs(mapping, page);
- if (page_count(page) != expected_count)
+ expected_count = folio_expected_refs(mapping, src);
+ if (folio_ref_count(src) != expected_count)
return -EAGAIN;
- head = page_buffers(page);
if (!buffer_migrate_lock_buffers(head, mode))
return -EAGAIN;
}
}
- rc = migrate_page_move_mapping(mapping, newpage, page, 0);
+ rc = folio_migrate_mapping(mapping, dst, src, 0);
if (rc != MIGRATEPAGE_SUCCESS)
goto unlock_buffers;
- attach_page_private(newpage, detach_page_private(page));
+ folio_attach_private(dst, folio_detach_private(src));
bh = head;
do {
- set_bh_page(bh, newpage, bh_offset(bh));
+ set_bh_page(bh, &dst->page, bh_offset(bh));
bh = bh->b_this_page;
-
} while (bh != head);
if (mode != MIGRATE_SYNC_NO_COPY)
- migrate_page_copy(newpage, page);
+ folio_migrate_copy(dst, src);
else
- migrate_page_states(newpage, page);
+ folio_migrate_flags(dst, src);
rc = MIGRATEPAGE_SUCCESS;
unlock_buffers:
do {
unlock_buffer(bh);
bh = bh->b_this_page;
-
} while (bh != head);
return rc;
}
-/*
- * Migration function for pages with buffers. This function can only be used
- * if the underlying filesystem guarantees that no other references to "page"
- * exist. For example attached buffer heads are accessed only under page lock.
+/**
+ * buffer_migrate_folio() - Migration function for folios with buffers.
+ * @mapping: The address space containing @src.
+ * @dst: The folio to migrate to.
+ * @src: The folio to migrate from.
+ * @mode: How to migrate the folio.
+ *
+ * This function can only be used if the underlying filesystem guarantees
+ * that no other references to @src exist. For example attached buffer
+ * heads are accessed only under the folio lock. If your filesystem cannot
+ * provide this guarantee, buffer_migrate_folio_norefs() may be more
+ * appropriate.
+ *
+ * Return: 0 on success or a negative errno on failure.
*/
-int buffer_migrate_page(struct address_space *mapping,
- struct page *newpage, struct page *page, enum migrate_mode mode)
+int buffer_migrate_folio(struct address_space *mapping,
+ struct folio *dst, struct folio *src, enum migrate_mode mode)
{
- return __buffer_migrate_page(mapping, newpage, page, mode, false);
+ return __buffer_migrate_folio(mapping, dst, src, mode, false);
}
-EXPORT_SYMBOL(buffer_migrate_page);
+EXPORT_SYMBOL(buffer_migrate_folio);
-/*
- * Same as above except that this variant is more careful and checks that there
- * are also no buffer head references. This function is the right one for
- * mappings where buffer heads are directly looked up and referenced (such as
- * block device mappings).
+/**
+ * buffer_migrate_folio_norefs() - Migration function for folios with buffers.
+ * @mapping: The address space containing @src.
+ * @dst: The folio to migrate to.
+ * @src: The folio to migrate from.
+ * @mode: How to migrate the folio.
+ *
+ * Like buffer_migrate_folio() except that this variant is more careful
+ * and checks that there are also no buffer head references. This function
+ * is the right one for mappings where buffer heads are directly looked
+ * up and referenced (such as block device mappings).
+ *
+ * Return: 0 on success or a negative errno on failure.
*/
-int buffer_migrate_page_norefs(struct address_space *mapping,
- struct page *newpage, struct page *page, enum migrate_mode mode)
+int buffer_migrate_folio_norefs(struct address_space *mapping,
+ struct folio *dst, struct folio *src, enum migrate_mode mode)
{
- return __buffer_migrate_page(mapping, newpage, page, mode, true);
+ return __buffer_migrate_folio(mapping, dst, src, mode, true);
}
#endif
+int filemap_migrate_folio(struct address_space *mapping,
+ struct folio *dst, struct folio *src, enum migrate_mode mode)
+{
+ int ret;
+
+ ret = folio_migrate_mapping(mapping, dst, src, 0);
+ if (ret != MIGRATEPAGE_SUCCESS)
+ return ret;
+
+ if (folio_get_private(src))
+ folio_attach_private(dst, folio_detach_private(src));
+
+ if (mode != MIGRATE_SYNC_NO_COPY)
+ folio_migrate_copy(dst, src);
+ else
+ folio_migrate_flags(dst, src);
+ return MIGRATEPAGE_SUCCESS;
+}
+EXPORT_SYMBOL_GPL(filemap_migrate_folio);
+
/*
- * Writeback a page to clean the dirty state
+ * Writeback a folio to clean the dirty state
*/
-static int writeout(struct address_space *mapping, struct page *page)
+static int writeout(struct address_space *mapping, struct folio *folio)
{
- struct folio *folio = page_folio(page);
struct writeback_control wbc = {
.sync_mode = WB_SYNC_NONE,
.nr_to_write = 1,
/* No write method for the address space */
return -EINVAL;
- if (!clear_page_dirty_for_io(page))
+ if (!folio_clear_dirty_for_io(folio))
/* Someone else already triggered a write */
return -EAGAIN;
/*
- * A dirty page may imply that the underlying filesystem has
- * the page on some queue. So the page must be clean for
- * migration. Writeout may mean we loose the lock and the
- * page state is no longer what we checked for earlier.
+ * A dirty folio may imply that the underlying filesystem has
+ * the folio on some queue. So the folio must be clean for
+ * migration. Writeout may mean we lose the lock and the
+ * folio state is no longer what we checked for earlier.
* At this point we know that the migration attempt cannot
* be successful.
*/
remove_migration_ptes(folio, folio, false);
- rc = mapping->a_ops->writepage(page, &wbc);
+ rc = mapping->a_ops->writepage(&folio->page, &wbc);
if (rc != AOP_WRITEPAGE_ACTIVATE)
/* unlocked. Relock */
- lock_page(page);
+ folio_lock(folio);
return (rc < 0) ? -EIO : -EAGAIN;
}
/*
* Default handling if a filesystem does not provide a migration function.
*/
-static int fallback_migrate_page(struct address_space *mapping,
- struct page *newpage, struct page *page, enum migrate_mode mode)
+static int fallback_migrate_folio(struct address_space *mapping,
+ struct folio *dst, struct folio *src, enum migrate_mode mode)
{
- if (PageDirty(page)) {
- /* Only writeback pages in full synchronous migration */
+ if (folio_test_dirty(src)) {
+ /* Only writeback folios in full synchronous migration */
switch (mode) {
case MIGRATE_SYNC:
case MIGRATE_SYNC_NO_COPY:
default:
return -EBUSY;
}
- return writeout(mapping, page);
+ return writeout(mapping, src);
}
/*
* Buffers may be managed in a filesystem specific way.
* We must have no buffers or drop them.
*/
- if (page_has_private(page) &&
- !try_to_release_page(page, GFP_KERNEL))
+ if (folio_test_private(src) &&
+ !filemap_release_folio(src, GFP_KERNEL))
return mode == MIGRATE_SYNC ? -EAGAIN : -EBUSY;
- return migrate_page(mapping, newpage, page, mode);
+ return migrate_folio(mapping, dst, src, mode);
}
/*
static int move_to_new_folio(struct folio *dst, struct folio *src,
enum migrate_mode mode)
{
- struct address_space *mapping;
int rc = -EAGAIN;
bool is_lru = !__PageMovable(&src->page);
VM_BUG_ON_FOLIO(!folio_test_locked(src), src);
VM_BUG_ON_FOLIO(!folio_test_locked(dst), dst);
- mapping = folio_mapping(src);
-
if (likely(is_lru)) {
+ struct address_space *mapping = folio_mapping(src);
+
if (!mapping)
- rc = migrate_page(mapping, &dst->page, &src->page, mode);
- else if (mapping->a_ops->migratepage)
+ rc = migrate_folio(mapping, dst, src, mode);
+ else if (mapping->a_ops->migrate_folio)
/*
- * Most pages have a mapping and most filesystems
- * provide a migratepage callback. Anonymous pages
+ * Most folios have a mapping and most filesystems
+ * provide a migrate_folio callback. Anonymous folios
* are part of swap space which also has its own
- * migratepage callback. This is the most common path
+ * migrate_folio callback. This is the most common path
* for page migration.
*/
- rc = mapping->a_ops->migratepage(mapping, &dst->page,
- &src->page, mode);
+ rc = mapping->a_ops->migrate_folio(mapping, dst, src,
+ mode);
else
- rc = fallback_migrate_page(mapping, &dst->page,
- &src->page, mode);
+ rc = fallback_migrate_folio(mapping, dst, src, mode);
} else {
+ const struct movable_operations *mops;
+
/*
* In case of non-lru page, it could be released after
* isolation step. In that case, we shouldn't try migration.
goto out;
}
- rc = mapping->a_ops->migratepage(mapping, &dst->page,
- &src->page, mode);
+ mops = page_movable_ops(&src->page);
+ rc = mops->migrate_page(&dst->page, &src->page, mode);
WARN_ON_ONCE(rc == MIGRATEPAGE_SUCCESS &&
!folio_test_isolated(src));
}
projects / linux-2.6-microblaze.git / blobdiff