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Diffstat (limited to 'mm/page_io.c')
-rw-r--r--mm/page_io.c60
1 files changed, 2 insertions, 58 deletions
diff --git a/mm/page_io.c b/mm/page_io.c
index b417f000b49e..a9444e67ec20 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -51,54 +51,6 @@ void end_swap_bio_write(struct bio *bio)
bio_put(bio);
}
-static void swap_slot_free_notify(struct page *page)
-{
- struct swap_info_struct *sis;
- struct gendisk *disk;
- swp_entry_t entry;
-
- /*
- * There is no guarantee that the page is in swap cache - the software
- * suspend code (at least) uses end_swap_bio_read() against a non-
- * swapcache page. So we must check PG_swapcache before proceeding with
- * this optimization.
- */
- if (unlikely(!PageSwapCache(page)))
- return;
-
- sis = page_swap_info(page);
- if (data_race(!(sis->flags & SWP_BLKDEV)))
- return;
-
- /*
- * The swap subsystem performs lazy swap slot freeing,
- * expecting that the page will be swapped out again.
- * So we can avoid an unnecessary write if the page
- * isn't redirtied.
- * This is good for real swap storage because we can
- * reduce unnecessary I/O and enhance wear-leveling
- * if an SSD is used as the as swap device.
- * But if in-memory swap device (eg zram) is used,
- * this causes a duplicated copy between uncompressed
- * data in VM-owned memory and compressed data in
- * zram-owned memory. So let's free zram-owned memory
- * and make the VM-owned decompressed page *dirty*,
- * so the page should be swapped out somewhere again if
- * we again wish to reclaim it.
- */
- disk = sis->bdev->bd_disk;
- entry.val = page_private(page);
- if (disk->fops->swap_slot_free_notify && __swap_count(entry) == 1) {
- unsigned long offset;
-
- offset = swp_offset(entry);
-
- SetPageDirty(page);
- disk->fops->swap_slot_free_notify(sis->bdev,
- offset);
- }
-}
-
static void end_swap_bio_read(struct bio *bio)
{
struct page *page = bio_first_page_all(bio);
@@ -114,7 +66,6 @@ static void end_swap_bio_read(struct bio *bio)
}
SetPageUptodate(page);
- swap_slot_free_notify(page);
out:
unlock_page(page);
WRITE_ONCE(bio->bi_private, NULL);
@@ -385,7 +336,7 @@ int swap_readpage(struct page *page, bool synchronous)
struct file *swap_file = sis->swap_file;
struct address_space *mapping = swap_file->f_mapping;
- ret = mapping->a_ops->readpage(swap_file, page);
+ ret = mapping->a_ops->read_folio(swap_file, page_folio(page));
if (!ret)
count_vm_event(PSWPIN);
goto out;
@@ -394,11 +345,6 @@ int swap_readpage(struct page *page, bool synchronous)
if (sis->flags & SWP_SYNCHRONOUS_IO) {
ret = bdev_read_page(sis->bdev, swap_page_sector(page), page);
if (!ret) {
- if (trylock_page(page)) {
- swap_slot_free_notify(page);
- unlock_page(page);
- }
-
count_vm_event(PSWPIN);
goto out;
}
@@ -414,7 +360,6 @@ int swap_readpage(struct page *page, bool synchronous)
* attempt to access it in the page fault retry time check.
*/
if (synchronous) {
- bio->bi_opf |= REQ_POLLED;
get_task_struct(current);
bio->bi_private = current;
}
@@ -426,8 +371,7 @@ int swap_readpage(struct page *page, bool synchronous)
if (!READ_ONCE(bio->bi_private))
break;
- if (!bio_poll(bio, NULL, 0))
- blk_io_schedule();
+ blk_io_schedule();
}
__set_current_state(TASK_RUNNING);
bio_put(bio);