diff options
| -rw-r--r-- | include/linux/mm.h | 2 | ||||
| -rw-r--r-- | include/linux/mm_types.h | 3 | ||||
| -rw-r--r-- | mm/internal.h | 5 | ||||
| -rw-r--r-- | mm/page_alloc.c | 12 |
4 files changed, 15 insertions, 7 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 860082ba8978..f366c180f2b6 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1333,6 +1333,8 @@ static inline int is_vmalloc_or_module_addr(const void *x) static inline int folio_entire_mapcount(const struct folio *folio) { VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); + if (!IS_ENABLED(CONFIG_64BIT) && unlikely(folio_large_order(folio) == 1)) + return 0; return atomic_read(&folio->_entire_mapcount) + 1; } diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 3ea2019a1aac..9499eb8e8e66 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -385,9 +385,9 @@ struct folio { struct { /* public: */ atomic_t _large_mapcount; - atomic_t _entire_mapcount; atomic_t _nr_pages_mapped; #ifdef CONFIG_64BIT + atomic_t _entire_mapcount; atomic_t _pincount; #endif /* CONFIG_64BIT */ /* private: the union with struct page is transitional */ @@ -411,6 +411,7 @@ struct folio { /* public: */ struct list_head _deferred_list; #ifndef CONFIG_64BIT + atomic_t _entire_mapcount; atomic_t _pincount; #endif /* !CONFIG_64BIT */ /* private: the union with struct page is transitional */ diff --git a/mm/internal.h b/mm/internal.h index 2d44a4c9d282..fcf0aeae3934 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -762,10 +762,11 @@ static inline void prep_compound_head(struct page *page, unsigned int order) folio_set_order(folio, order); atomic_set(&folio->_large_mapcount, -1); - atomic_set(&folio->_entire_mapcount, -1); atomic_set(&folio->_nr_pages_mapped, 0); - if (IS_ENABLED(CONFIG_64BIT) || order > 1) + if (IS_ENABLED(CONFIG_64BIT) || order > 1) { atomic_set(&folio->_pincount, 0); + atomic_set(&folio->_entire_mapcount, -1); + } if (order > 1) INIT_LIST_HEAD(&folio->_deferred_list); } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 2a9aa4439a66..e456a43811fd 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -947,10 +947,6 @@ static int free_tail_page_prepare(struct page *head_page, struct page *page) switch (page - head_page) { case 1: /* the first tail page: these may be in place of ->mapping */ - if (unlikely(folio_entire_mapcount(folio))) { - bad_page(page, "nonzero entire_mapcount"); - goto out; - } if (unlikely(folio_large_mapcount(folio))) { bad_page(page, "nonzero large_mapcount"); goto out; @@ -960,6 +956,10 @@ static int free_tail_page_prepare(struct page *head_page, struct page *page) goto out; } if (IS_ENABLED(CONFIG_64BIT)) { + if (unlikely(atomic_read(&folio->_entire_mapcount) + 1)) { + bad_page(page, "nonzero entire_mapcount"); + goto out; + } if (unlikely(atomic_read(&folio->_pincount))) { bad_page(page, "nonzero pincount"); goto out; @@ -973,6 +973,10 @@ static int free_tail_page_prepare(struct page *head_page, struct page *page) goto out; } if (!IS_ENABLED(CONFIG_64BIT)) { + if (unlikely(atomic_read(&folio->_entire_mapcount) + 1)) { + bad_page(page, "nonzero entire_mapcount"); + goto out; + } if (unlikely(atomic_read(&folio->_pincount))) { bad_page(page, "nonzero pincount"); goto out; |