diff options
Diffstat (limited to 'mm/swap.h')
| -rw-r--r-- | mm/swap.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/mm/swap.h b/mm/swap.h index aa62463976d5..2269eb9df0af 100644 --- a/mm/swap.h +++ b/mm/swap.h @@ -201,4 +201,22 @@ static inline int swap_zeromap_batch(swp_entry_t entry, int max_nr, #endif /* CONFIG_SWAP */ +/** + * folio_index - File index of a folio. + * @folio: The folio. + * + * For a folio which is either in the page cache or the swap cache, + * return its index within the address_space it belongs to. If you know + * the folio is definitely in the page cache, you can look at the folio's + * index directly. + * + * Return: The index (offset in units of pages) of a folio in its file. + */ +static inline pgoff_t folio_index(struct folio *folio) +{ + if (unlikely(folio_test_swapcache(folio))) + return swap_cache_index(folio->swap); + return folio->index; +} + #endif /* _MM_SWAP_H */ |