diff options
| -rw-r--r-- | include/linux/swap.h | 5 | ||||
| -rw-r--r-- | mm/swapfile.c | 47 |
2 files changed, 52 insertions, 0 deletions
diff --git a/include/linux/swap.h b/include/linux/swap.h index bd450023b9a4..0f41fe49c9dc 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -478,6 +478,7 @@ extern void swap_shmem_alloc(swp_entry_t); extern int swap_duplicate(swp_entry_t); extern int swapcache_prepare(swp_entry_t); extern void swap_free(swp_entry_t); +extern void swap_free_nr(swp_entry_t entry, int nr_pages); extern void swapcache_free_entries(swp_entry_t *entries, int n); extern void free_swap_and_cache_nr(swp_entry_t entry, int nr); int swap_type_of(dev_t device, sector_t offset); @@ -559,6 +560,10 @@ static inline void swap_free(swp_entry_t swp) { } +static inline void swap_free_nr(swp_entry_t entry, int nr_pages) +{ +} + static inline void put_swap_folio(struct folio *folio, swp_entry_t swp) { } diff --git a/mm/swapfile.c b/mm/swapfile.c index f1e559e216bd..92a045d34a97 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1356,6 +1356,53 @@ void swap_free(swp_entry_t entry) __swap_entry_free(p, entry); } +static void cluster_swap_free_nr(struct swap_info_struct *sis, + unsigned long offset, int nr_pages) +{ + struct swap_cluster_info *ci; + DECLARE_BITMAP(to_free, BITS_PER_LONG) = { 0 }; + int i, nr; + + ci = lock_cluster_or_swap_info(sis, offset); + while (nr_pages) { + nr = min(BITS_PER_LONG, nr_pages); + for (i = 0; i < nr; i++) { + if (!__swap_entry_free_locked(sis, offset + i, 1)) + bitmap_set(to_free, i, 1); + } + if (!bitmap_empty(to_free, BITS_PER_LONG)) { + unlock_cluster_or_swap_info(sis, ci); + for_each_set_bit(i, to_free, BITS_PER_LONG) + free_swap_slot(swp_entry(sis->type, offset + i)); + if (nr == nr_pages) + return; + bitmap_clear(to_free, 0, BITS_PER_LONG); + ci = lock_cluster_or_swap_info(sis, offset); + } + offset += nr; + nr_pages -= nr; + } + unlock_cluster_or_swap_info(sis, ci); +} + +void swap_free_nr(swp_entry_t entry, int nr_pages) +{ + int nr; + struct swap_info_struct *sis; + unsigned long offset = swp_offset(entry); + + sis = _swap_info_get(entry); + if (!sis) + return; + + while (nr_pages) { + nr = min_t(int, nr_pages, SWAPFILE_CLUSTER - offset % SWAPFILE_CLUSTER); + cluster_swap_free_nr(sis, offset, nr); + offset += nr; + nr_pages -= nr; + } +} + /* * Called after dropping swapcache to decrease refcnt to swap entries. */ |