@@ -393,29 +393,24 @@ static int folio_expected_refs(struct address_space *mapping,
}
/*
- * Replace the page in the mapping.
+ * Replace the folio in the mapping.
*
* The number of remaining references must be:
- * 1 for anonymous pages without a mapping
- * 2 for pages with a mapping
- * 3 for pages with a mapping and PagePrivate/PagePrivate2 set.
+ * 1 for anonymous folios without a mapping
+ * 2 for folios with a mapping
+ * 3 for folios with a mapping and PagePrivate/PagePrivate2 set.
*/
-int folio_migrate_mapping(struct address_space *mapping,
- struct folio *newfolio, struct folio *folio, int extra_count)
+static int __folio_migrate_mapping(struct address_space *mapping,
+ struct folio *newfolio, struct folio *folio, int expected_count)
{
XA_STATE(xas, &mapping->i_pages, folio_index(folio));
struct zone *oldzone, *newzone;
int dirty;
- int expected_count = folio_expected_refs(mapping, folio) + extra_count;
long nr = folio_nr_pages(folio);
long entries, i;
if (!mapping) {
- /* Anonymous page without mapping */
- if (folio_ref_count(folio) != expected_count)
- return -EAGAIN;
-
- /* No turning back from here */
+ /* Anonymous folio without mapping, no turning back from here */
newfolio->index = folio->index;
newfolio->mapping = folio->mapping;
if (folio_test_swapbacked(folio))
@@ -452,7 +447,7 @@ int folio_migrate_mapping(struct address_space *mapping,
entries = 1;
}
- /* Move dirty while page refs frozen and newpage not yet exposed */
+ /* Move dirty while folio refs frozen and newfolio not yet exposed */
dirty = folio_test_dirty(folio);
if (dirty) {
folio_clear_dirty(folio);
@@ -466,7 +461,7 @@ int folio_migrate_mapping(struct address_space *mapping,
}
/*
- * Drop cache reference from old page by unfreezing
+ * Drop cache reference from old folio by unfreezing
* to one less reference.
* We know this isn't the last reference.
*/
@@ -477,11 +472,11 @@ int folio_migrate_mapping(struct address_space *mapping,
/*
* If moved to a different zone then also account
- * the page for that zone. Other VM counters will be
+ * the folio for that zone. Other VM counters will be
* taken care of when we establish references to the
- * new page and drop references to the old page.
+ * new folio and drop references to the old folio.
*
- * Note that anonymous pages are accounted for
+ * Note that anonymous folios are accounted for
* via NR_FILE_PAGES and NR_ANON_MAPPED if they
* are mapped to swap space.
*/
@@ -521,6 +516,17 @@ int folio_migrate_mapping(struct address_space *mapping,
return MIGRATEPAGE_SUCCESS;
}
+
+int folio_migrate_mapping(struct address_space *mapping,
+ struct folio *newfolio, struct folio *folio, int extra_count)
+{
+ int expected_count = folio_expected_refs(mapping, folio) + extra_count;
+
+ if (folio_ref_count(folio) != expected_count)
+ return -EAGAIN;
+
+ return __folio_migrate_mapping(mapping, newfolio, folio, expected_count);
+}
EXPORT_SYMBOL(folio_migrate_mapping);
/*
The folio refcount check is moved out for both !mapping and mapping folio, also update comment from page to folio for folio_migrate_mapping(). No functional change intended. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> --- mm/migrate.c | 40 +++++++++++++++++++++++----------------- 1 file changed, 23 insertions(+), 17 deletions(-)