diff options
| -rw-r--r-- | mm/migrate.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index 462163f5f278..94c9ebf1f33e 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -424,6 +424,22 @@ static inline bool buffer_migrate_lock_buffers(struct buffer_head *head, } #endif /* CONFIG_BLOCK */ +static int expected_page_refs(struct page *page) +{ + int expected_count = 1; + + /* + * Device public or private pages have an extra refcount as they are + * ZONE_DEVICE pages. + */ + expected_count += is_device_private_page(page); + expected_count += is_device_public_page(page); + if (page_mapping(page)) + expected_count += hpage_nr_pages(page) + page_has_private(page); + + return expected_count; +} + /* * Replace the page in the mapping. * @@ -440,14 +456,7 @@ int migrate_page_move_mapping(struct address_space *mapping, XA_STATE(xas, &mapping->i_pages, page_index(page)); struct zone *oldzone, *newzone; int dirty; - int expected_count = 1 + extra_count; - - /* - * Device public or private pages have an extra refcount as they are - * ZONE_DEVICE pages. - */ - expected_count += is_device_private_page(page); - expected_count += is_device_public_page(page); + int expected_count = expected_page_refs(page) + extra_count; if (!mapping) { /* Anonymous page without mapping */ @@ -467,8 +476,6 @@ int migrate_page_move_mapping(struct address_space *mapping, newzone = page_zone(newpage); xas_lock_irq(&xas); - - expected_count += hpage_nr_pages(page) + page_has_private(page); if (page_count(page) != expected_count || xas_load(&xas) != page) { xas_unlock_irq(&xas); return -EAGAIN; |