diff options
Diffstat (limited to 'include/linux/pagemap.h')
| -rw-r--r-- | include/linux/pagemap.h | 52 |
1 files changed, 24 insertions, 28 deletions
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 1f50991b43e3..2c3718d592d6 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -513,39 +513,37 @@ static inline bool mapping_large_folio_support(const struct address_space *mappi return mapping_max_folio_order(mapping) > 0; } -/* Return the maximum folio size for this pagecache mapping, in bytes. */ -static inline size_t mapping_max_folio_size(const struct address_space *mapping) +/** + * mapping_pmd_folio_support() - Check if a mapping supports PMD-sized folio + * @mapping: The address_space + * + * While some mappings support large folios, they might not support PMD-sized + * folios. This function checks whether a mapping supports PMD-sized folios. + * For example, khugepaged needs this information before attempting to + * collapsing THPs. + * + * Return: True if PMD-sized folios are supported, otherwise false. + */ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static inline bool mapping_pmd_folio_support(const struct address_space *mapping) { - return PAGE_SIZE << mapping_max_folio_order(mapping); -} + /* AS_FOLIO_ORDER is only reasonable for pagecache folios */ + VM_WARN_ON_ONCE((unsigned long)mapping & FOLIO_MAPPING_ANON); -static inline int filemap_nr_thps(const struct address_space *mapping) -{ -#ifdef CONFIG_READ_ONLY_THP_FOR_FS - return atomic_read(&mapping->nr_thps); -#else - return 0; -#endif + return mapping_min_folio_order(mapping) <= PMD_ORDER && + mapping_max_folio_order(mapping) >= PMD_ORDER; } - -static inline void filemap_nr_thps_inc(struct address_space *mapping) -{ -#ifdef CONFIG_READ_ONLY_THP_FOR_FS - if (!mapping_large_folio_support(mapping)) - atomic_inc(&mapping->nr_thps); #else - WARN_ON_ONCE(mapping_large_folio_support(mapping) == 0); -#endif +static inline bool mapping_pmd_folio_support(const struct address_space *mapping) +{ + return false; } +#endif -static inline void filemap_nr_thps_dec(struct address_space *mapping) +/* Return the maximum folio size for this pagecache mapping, in bytes. */ +static inline size_t mapping_max_folio_size(const struct address_space *mapping) { -#ifdef CONFIG_READ_ONLY_THP_FOR_FS - if (!mapping_large_folio_support(mapping)) - atomic_dec(&mapping->nr_thps); -#else - WARN_ON_ONCE(mapping_large_folio_support(mapping) == 0); -#endif + return PAGE_SIZE << mapping_max_folio_order(mapping); } struct address_space *folio_mapping(const struct folio *folio); @@ -1350,7 +1348,6 @@ struct readahead_control { struct file_ra_state *ra; /* private: use the readahead_* accessors instead */ pgoff_t _index; - pgoff_t _max_index; /* limit readahead to _max_index, inclusive */ unsigned int _nr_pages; unsigned int _batch_count; bool dropbehind; @@ -1364,7 +1361,6 @@ struct readahead_control { .mapping = m, \ .ra = r, \ ._index = i, \ - ._max_index = ULONG_MAX, \ } #define VM_READAHEAD_PAGES (SZ_128K / PAGE_SIZE) |