1 files changed, 322 insertions, 252 deletions

diff --git a/mm/page_io.c b/mm/page_io.c
index 433df1263349..ae2b49055e43 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -18,129 +18,61 @@
 #include <linux/swap.h>
 #include <linux/bio.h>
 #include <linux/swapops.h>
-#include <linux/buffer_head.h>
 #include <linux/writeback.h>
-#include <linux/frontswap.h>
 #include <linux/blkdev.h>
 #include <linux/psi.h>
 #include <linux/uio.h>
 #include <linux/sched/task.h>
+#include <linux/delayacct.h>
+#include <linux/zswap.h>
+#include "swap.h"
 
-static struct bio *get_swap_bio(gfp_t gfp_flags,
-				struct page *page, bio_end_io_t end_io)
+static void __end_swap_bio_write(struct bio *bio)
 {
-	struct bio *bio;
-
-	bio = bio_alloc(gfp_flags, 1);
-	if (bio) {
-		struct block_device *bdev;
-
-		bio->bi_iter.bi_sector = map_swap_page(page, &bdev);
-		bio_set_dev(bio, bdev);
-		bio->bi_iter.bi_sector <<= PAGE_SHIFT - 9;
-		bio->bi_end_io = end_io;
-
-		bio_add_page(bio, page, thp_size(page), 0);
-	}
-	return bio;
-}
-
-void end_swap_bio_write(struct bio *bio)
-{
-	struct page *page = bio_first_page_all(bio);
+	struct folio *folio = bio_first_folio_all(bio);
 
 	if (bio->bi_status) {
-		SetPageError(page);
 		/*
 		 * We failed to write the page out to swap-space.
 		 * Re-dirty the page in order to avoid it being reclaimed.
 		 * Also print a dire warning that things will go BAD (tm)
 		 * very quickly.
 		 *
-		 * Also clear PG_reclaim to avoid rotate_reclaimable_page()
+		 * Also clear PG_reclaim to avoid folio_rotate_reclaimable()
 		 */
-		set_page_dirty(page);
-		pr_alert("Write-error on swap-device (%u:%u:%llu)\n",
-			 MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
-			 (unsigned long long)bio->bi_iter.bi_sector);
-		ClearPageReclaim(page);
+		folio_mark_dirty(folio);
+		pr_alert_ratelimited("Write-error on swap-device (%u:%u:%llu)\n",
+				     MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
+				     (unsigned long long)bio->bi_iter.bi_sector);
+		folio_clear_reclaim(folio);
 	}
-	end_page_writeback(page);
-	bio_put(bio);
+	folio_end_writeback(folio);
 }
 
-static void swap_slot_free_notify(struct page *page)
+static void end_swap_bio_write(struct bio *bio)
 {
-	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);
-	}
+	__end_swap_bio_write(bio);
+	bio_put(bio);
 }
 
-static void end_swap_bio_read(struct bio *bio)
+static void __end_swap_bio_read(struct bio *bio)
 {
-	struct page *page = bio_first_page_all(bio);
-	struct task_struct *waiter = bio->bi_private;
+	struct folio *folio = bio_first_folio_all(bio);
 
 	if (bio->bi_status) {
-		SetPageError(page);
-		ClearPageUptodate(page);
-		pr_alert("Read-error on swap-device (%u:%u:%llu)\n",
-			 MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
-			 (unsigned long long)bio->bi_iter.bi_sector);
-		goto out;
+		pr_alert_ratelimited("Read-error on swap-device (%u:%u:%llu)\n",
+				     MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
+				     (unsigned long long)bio->bi_iter.bi_sector);
+	} else {
+		folio_mark_uptodate(folio);
 	}
+	folio_unlock(folio);
+}
 
-	SetPageUptodate(page);
-	swap_slot_free_notify(page);
-out:
-	unlock_page(page);
-	WRITE_ONCE(bio->bi_private, NULL);
+static void end_swap_bio_read(struct bio *bio)
+{
+	__end_swap_bio_read(bio);
 	bio_put(bio);
-	if (waiter) {
-		blk_wake_io_task(waiter);
-		put_task_struct(waiter);
-	}
 }
 
 int generic_swapfile_activate(struct swap_info_struct *sis,
@@ -246,231 +178,369 @@ bad_bmap:
  */
 int swap_writepage(struct page *page, struct writeback_control *wbc)
 {
-	int ret = 0;
+	struct folio *folio = page_folio(page);
+	int ret;
 
-	if (try_to_free_swap(page)) {
-		unlock_page(page);
-		goto out;
+	if (folio_free_swap(folio)) {
+		folio_unlock(folio);
+		return 0;
 	}
 	/*
 	 * Arch code may have to preserve more data than just the page
 	 * contents, e.g. memory tags.
 	 */
-	ret = arch_prepare_to_swap(page);
+	ret = arch_prepare_to_swap(&folio->page);
 	if (ret) {
-		set_page_dirty(page);
-		unlock_page(page);
-		goto out;
+		folio_mark_dirty(folio);
+		folio_unlock(folio);
+		return ret;
 	}
-	if (frontswap_store(page) == 0) {
-		set_page_writeback(page);
-		unlock_page(page);
-		end_page_writeback(page);
-		goto out;
+	if (zswap_store(folio)) {
+		folio_start_writeback(folio);
+		folio_unlock(folio);
+		folio_end_writeback(folio);
+		return 0;
+	}
+	if (!mem_cgroup_zswap_writeback_enabled(folio_memcg(folio))) {
+		folio_mark_dirty(folio);
+		return AOP_WRITEPAGE_ACTIVATE;
 	}
-	ret = __swap_writepage(page, wbc, end_swap_bio_write);
-out:
-	return ret;
-}
 
-static sector_t swap_page_sector(struct page *page)
-{
-	return (sector_t)__page_file_index(page) << (PAGE_SHIFT - 9);
+	__swap_writepage(folio, wbc);
+	return 0;
 }
 
-static inline void count_swpout_vm_event(struct page *page)
+static inline void count_swpout_vm_event(struct folio *folio)
 {
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	if (unlikely(PageTransHuge(page)))
+	if (unlikely(folio_test_pmd_mappable(folio))) {
+		count_memcg_folio_events(folio, THP_SWPOUT, 1);
 		count_vm_event(THP_SWPOUT);
+	}
 #endif
-	count_vm_events(PSWPOUT, thp_nr_pages(page));
+	count_vm_events(PSWPOUT, folio_nr_pages(folio));
 }
 
 #if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
-static void bio_associate_blkg_from_page(struct bio *bio, struct page *page)
+static void bio_associate_blkg_from_page(struct bio *bio, struct folio *folio)
 {
 	struct cgroup_subsys_state *css;
+	struct mem_cgroup *memcg;
 
-	if (!page->mem_cgroup)
+	memcg = folio_memcg(folio);
+	if (!memcg)
 		return;
 
 	rcu_read_lock();
-	css = cgroup_e_css(page->mem_cgroup->css.cgroup, &io_cgrp_subsys);
+	css = cgroup_e_css(memcg->css.cgroup, &io_cgrp_subsys);
 	bio_associate_blkg_from_css(bio, css);
 	rcu_read_unlock();
 }
 #else
-#define bio_associate_blkg_from_page(bio, page)		do { } while (0)
+#define bio_associate_blkg_from_page(bio, folio)		do { } while (0)
 #endif /* CONFIG_MEMCG && CONFIG_BLK_CGROUP */
 
-int __swap_writepage(struct page *page, struct writeback_control *wbc,
-		bio_end_io_t end_write_func)
+struct swap_iocb {
+	struct kiocb		iocb;
+	struct bio_vec		bvec[SWAP_CLUSTER_MAX];
+	int			pages;
+	int			len;
+};
+static mempool_t *sio_pool;
+
+int sio_pool_init(void)
 {
-	struct bio *bio;
-	int ret;
-	struct swap_info_struct *sis = page_swap_info(page);
-
-	VM_BUG_ON_PAGE(!PageSwapCache(page), page);
-	if (data_race(sis->flags & SWP_FS_OPS)) {
-		struct kiocb kiocb;
-		struct file *swap_file = sis->swap_file;
-		struct address_space *mapping = swap_file->f_mapping;
-		struct bio_vec bv = {
-			.bv_page = page,
-			.bv_len  = PAGE_SIZE,
-			.bv_offset = 0
-		};
-		struct iov_iter from;
-
-		iov_iter_bvec(&from, WRITE, &bv, 1, PAGE_SIZE);
-		init_sync_kiocb(&kiocb, swap_file);
-		kiocb.ki_pos = page_file_offset(page);
-
-		set_page_writeback(page);
-		unlock_page(page);
-		ret = mapping->a_ops->direct_IO(&kiocb, &from);
-		if (ret == PAGE_SIZE) {
-			count_vm_event(PSWPOUT);
-			ret = 0;
-		} else {
-			/*
-			 * In the case of swap-over-nfs, this can be a
-			 * temporary failure if the system has limited
-			 * memory for allocating transmit buffers.
-			 * Mark the page dirty and avoid
-			 * rotate_reclaimable_page but rate-limit the
-			 * messages but do not flag PageError like
-			 * the normal direct-to-bio case as it could
-			 * be temporary.
-			 */
+	if (!sio_pool) {
+		mempool_t *pool = mempool_create_kmalloc_pool(
+			SWAP_CLUSTER_MAX, sizeof(struct swap_iocb));
+		if (cmpxchg(&sio_pool, NULL, pool))
+			mempool_destroy(pool);
+	}
+	if (!sio_pool)
+		return -ENOMEM;
+	return 0;
+}
+
+static void sio_write_complete(struct kiocb *iocb, long ret)
+{
+	struct swap_iocb *sio = container_of(iocb, struct swap_iocb, iocb);
+	struct page *page = sio->bvec[0].bv_page;
+	int p;
+
+	if (ret != sio->len) {
+		/*
+		 * In the case of swap-over-nfs, this can be a
+		 * temporary failure if the system has limited
+		 * memory for allocating transmit buffers.
+		 * Mark the page dirty and avoid
+		 * folio_rotate_reclaimable but rate-limit the
+		 * messages but do not flag PageError like
+		 * the normal direct-to-bio case as it could
+		 * be temporary.
+		 */
+		pr_err_ratelimited("Write error %ld on dio swapfile (%llu)\n",
+				   ret, page_file_offset(page));
+		for (p = 0; p < sio->pages; p++) {
+			page = sio->bvec[p].bv_page;
 			set_page_dirty(page);
 			ClearPageReclaim(page);
-			pr_err_ratelimited("Write error on dio swapfile (%llu)\n",
-					   page_file_offset(page));
 		}
-		end_page_writeback(page);
-		return ret;
 	}
 
-	ret = bdev_write_page(sis->bdev, swap_page_sector(page), page, wbc);
-	if (!ret) {
-		count_swpout_vm_event(page);
-		return 0;
-	}
+	for (p = 0; p < sio->pages; p++)
+		end_page_writeback(sio->bvec[p].bv_page);
 
-	bio = get_swap_bio(GFP_NOIO, page, end_write_func);
-	if (bio == NULL) {
-		set_page_dirty(page);
-		unlock_page(page);
-		return -ENOMEM;
+	mempool_free(sio, sio_pool);
+}
+
+static void swap_writepage_fs(struct folio *folio, struct writeback_control *wbc)
+{
+	struct swap_iocb *sio = NULL;
+	struct swap_info_struct *sis = swp_swap_info(folio->swap);
+	struct file *swap_file = sis->swap_file;
+	loff_t pos = folio_file_pos(folio);
+
+	count_swpout_vm_event(folio);
+	folio_start_writeback(folio);
+	folio_unlock(folio);
+	if (wbc->swap_plug)
+		sio = *wbc->swap_plug;
+	if (sio) {
+		if (sio->iocb.ki_filp != swap_file ||
+		    sio->iocb.ki_pos + sio->len != pos) {
+			swap_write_unplug(sio);
+			sio = NULL;
+		}
 	}
-	bio->bi_opf = REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc);
-	bio_associate_blkg_from_page(bio, page);
-	count_swpout_vm_event(page);
-	set_page_writeback(page);
-	unlock_page(page);
-	submit_bio(bio);
+	if (!sio) {
+		sio = mempool_alloc(sio_pool, GFP_NOIO);
+		init_sync_kiocb(&sio->iocb, swap_file);
+		sio->iocb.ki_complete = sio_write_complete;
+		sio->iocb.ki_pos = pos;
+		sio->pages = 0;
+		sio->len = 0;
+	}
+	bvec_set_folio(&sio->bvec[sio->pages], folio, folio_size(folio), 0);
+	sio->len += folio_size(folio);
+	sio->pages += 1;
+	if (sio->pages == ARRAY_SIZE(sio->bvec) || !wbc->swap_plug) {
+		swap_write_unplug(sio);
+		sio = NULL;
+	}
+	if (wbc->swap_plug)
+		*wbc->swap_plug = sio;
+}
 
-	return 0;
+static void swap_writepage_bdev_sync(struct folio *folio,
+		struct writeback_control *wbc, struct swap_info_struct *sis)
+{
+	struct bio_vec bv;
+	struct bio bio;
+
+	bio_init(&bio, sis->bdev, &bv, 1,
+		 REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc));
+	bio.bi_iter.bi_sector = swap_folio_sector(folio);
+	bio_add_folio_nofail(&bio, folio, folio_size(folio), 0);
+
+	bio_associate_blkg_from_page(&bio, folio);
+	count_swpout_vm_event(folio);
+
+	folio_start_writeback(folio);
+	folio_unlock(folio);
+
+	submit_bio_wait(&bio);
+	__end_swap_bio_write(&bio);
 }
 
-int swap_readpage(struct page *page, bool synchronous)
+static void swap_writepage_bdev_async(struct folio *folio,
+		struct writeback_control *wbc, struct swap_info_struct *sis)
 {
 	struct bio *bio;
-	int ret = 0;
-	struct swap_info_struct *sis = page_swap_info(page);
-	blk_qc_t qc;
-	struct gendisk *disk;
-	unsigned long pflags;
 
-	VM_BUG_ON_PAGE(!PageSwapCache(page) && !synchronous, page);
-	VM_BUG_ON_PAGE(!PageLocked(page), page);
-	VM_BUG_ON_PAGE(PageUptodate(page), page);
+	bio = bio_alloc(sis->bdev, 1,
+			REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc),
+			GFP_NOIO);
+	bio->bi_iter.bi_sector = swap_folio_sector(folio);
+	bio->bi_end_io = end_swap_bio_write;
+	bio_add_folio_nofail(bio, folio, folio_size(folio), 0);
+
+	bio_associate_blkg_from_page(bio, folio);
+	count_swpout_vm_event(folio);
+	folio_start_writeback(folio);
+	folio_unlock(folio);
+	submit_bio(bio);
+}
+
+void __swap_writepage(struct folio *folio, struct writeback_control *wbc)
+{
+	struct swap_info_struct *sis = swp_swap_info(folio->swap);
 
+	VM_BUG_ON_FOLIO(!folio_test_swapcache(folio), folio);
 	/*
-	 * Count submission time as memory stall. When the device is congested,
-	 * or the submitting cgroup IO-throttled, submission can be a
-	 * significant part of overall IO time.
+	 * ->flags can be updated non-atomicially (scan_swap_map_slots),
+	 * but that will never affect SWP_FS_OPS, so the data_race
+	 * is safe.
 	 */
-	psi_memstall_enter(&pflags);
+	if (data_race(sis->flags & SWP_FS_OPS))
+		swap_writepage_fs(folio, wbc);
+	else if (sis->flags & SWP_SYNCHRONOUS_IO)
+		swap_writepage_bdev_sync(folio, wbc, sis);
+	else
+		swap_writepage_bdev_async(folio, wbc, sis);
+}
 
-	if (frontswap_load(page) == 0) {
-		SetPageUptodate(page);
-		unlock_page(page);
-		goto out;
-	}
+void swap_write_unplug(struct swap_iocb *sio)
+{
+	struct iov_iter from;
+	struct address_space *mapping = sio->iocb.ki_filp->f_mapping;
+	int ret;
 
-	if (data_race(sis->flags & SWP_FS_OPS)) {
-		struct file *swap_file = sis->swap_file;
-		struct address_space *mapping = swap_file->f_mapping;
+	iov_iter_bvec(&from, ITER_SOURCE, sio->bvec, sio->pages, sio->len);
+	ret = mapping->a_ops->swap_rw(&sio->iocb, &from);
+	if (ret != -EIOCBQUEUED)
+		sio_write_complete(&sio->iocb, ret);
+}
 
-		ret = mapping->a_ops->readpage(swap_file, page);
-		if (!ret)
-			count_vm_event(PSWPIN);
-		goto out;
-	}
+static void sio_read_complete(struct kiocb *iocb, long ret)
+{
+	struct swap_iocb *sio = container_of(iocb, struct swap_iocb, iocb);
+	int p;
 
-	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);
-			}
+	if (ret == sio->len) {
+		for (p = 0; p < sio->pages; p++) {
+			struct folio *folio = page_folio(sio->bvec[p].bv_page);
 
-			count_vm_event(PSWPIN);
-			goto out;
+			folio_mark_uptodate(folio);
+			folio_unlock(folio);
 		}
+		count_vm_events(PSWPIN, sio->pages);
+	} else {
+		for (p = 0; p < sio->pages; p++) {
+			struct folio *folio = page_folio(sio->bvec[p].bv_page);
+
+			folio_unlock(folio);
+		}
+		pr_alert_ratelimited("Read-error on swap-device\n");
 	}
+	mempool_free(sio, sio_pool);
+}
 
-	ret = 0;
-	bio = get_swap_bio(GFP_KERNEL, page, end_swap_bio_read);
-	if (bio == NULL) {
-		unlock_page(page);
-		ret = -ENOMEM;
-		goto out;
+static void swap_read_folio_fs(struct folio *folio, struct swap_iocb **plug)
+{
+	struct swap_info_struct *sis = swp_swap_info(folio->swap);
+	struct swap_iocb *sio = NULL;
+	loff_t pos = folio_file_pos(folio);
+
+	if (plug)
+		sio = *plug;
+	if (sio) {
+		if (sio->iocb.ki_filp != sis->swap_file ||
+		    sio->iocb.ki_pos + sio->len != pos) {
+			swap_read_unplug(sio);
+			sio = NULL;
+		}
+	}
+	if (!sio) {
+		sio = mempool_alloc(sio_pool, GFP_KERNEL);
+		init_sync_kiocb(&sio->iocb, sis->swap_file);
+		sio->iocb.ki_pos = pos;
+		sio->iocb.ki_complete = sio_read_complete;
+		sio->pages = 0;
+		sio->len = 0;
 	}
-	disk = bio->bi_disk;
+	bvec_set_folio(&sio->bvec[sio->pages], folio, folio_size(folio), 0);
+	sio->len += folio_size(folio);
+	sio->pages += 1;
+	if (sio->pages == ARRAY_SIZE(sio->bvec) || !plug) {
+		swap_read_unplug(sio);
+		sio = NULL;
+	}
+	if (plug)
+		*plug = sio;
+}
+
+static void swap_read_folio_bdev_sync(struct folio *folio,
+		struct swap_info_struct *sis)
+{
+	struct bio_vec bv;
+	struct bio bio;
+
+	bio_init(&bio, sis->bdev, &bv, 1, REQ_OP_READ);
+	bio.bi_iter.bi_sector = swap_folio_sector(folio);
+	bio_add_folio_nofail(&bio, folio, folio_size(folio), 0);
 	/*
 	 * Keep this task valid during swap readpage because the oom killer may
 	 * attempt to access it in the page fault retry time check.
 	 */
-	bio_set_op_attrs(bio, REQ_OP_READ, 0);
-	if (synchronous) {
-		bio->bi_opf |= REQ_HIPRI;
-		get_task_struct(current);
-		bio->bi_private = current;
-	}
+	get_task_struct(current);
 	count_vm_event(PSWPIN);
-	bio_get(bio);
-	qc = submit_bio(bio);
-	while (synchronous) {
-		set_current_state(TASK_UNINTERRUPTIBLE);
-		if (!READ_ONCE(bio->bi_private))
-			break;
-
-		if (!blk_poll(disk->queue, qc, true))
-			blk_io_schedule();
-	}
-	__set_current_state(TASK_RUNNING);
-	bio_put(bio);
+	submit_bio_wait(&bio);
+	__end_swap_bio_read(&bio);
+	put_task_struct(current);
+}
 
-out:
-	psi_memstall_leave(&pflags);
-	return ret;
+static void swap_read_folio_bdev_async(struct folio *folio,
+		struct swap_info_struct *sis)
+{
+	struct bio *bio;
+
+	bio = bio_alloc(sis->bdev, 1, REQ_OP_READ, GFP_KERNEL);
+	bio->bi_iter.bi_sector = swap_folio_sector(folio);
+	bio->bi_end_io = end_swap_bio_read;
+	bio_add_folio_nofail(bio, folio, folio_size(folio), 0);
+	count_vm_event(PSWPIN);
+	submit_bio(bio);
 }
 
-int swap_set_page_dirty(struct page *page)
+void swap_read_folio(struct folio *folio, bool synchronous,
+		struct swap_iocb **plug)
 {
-	struct swap_info_struct *sis = page_swap_info(page);
+	struct swap_info_struct *sis = swp_swap_info(folio->swap);
+	bool workingset = folio_test_workingset(folio);
+	unsigned long pflags;
+	bool in_thrashing;
 
-	if (data_race(sis->flags & SWP_FS_OPS)) {
-		struct address_space *mapping = sis->swap_file->f_mapping;
+	VM_BUG_ON_FOLIO(!folio_test_swapcache(folio) && !synchronous, folio);
+	VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
+	VM_BUG_ON_FOLIO(folio_test_uptodate(folio), folio);
 
-		VM_BUG_ON_PAGE(!PageSwapCache(page), page);
-		return mapping->a_ops->set_page_dirty(page);
+	/*
+	 * Count submission time as memory stall and delay. When the device
+	 * is congested, or the submitting cgroup IO-throttled, submission
+	 * can be a significant part of overall IO time.
+	 */
+	if (workingset) {
+		delayacct_thrashing_start(&in_thrashing);
+		psi_memstall_enter(&pflags);
+	}
+	delayacct_swapin_start();
+
+	if (zswap_load(folio)) {
+		folio_mark_uptodate(folio);
+		folio_unlock(folio);
+	} else if (data_race(sis->flags & SWP_FS_OPS)) {
+		swap_read_folio_fs(folio, plug);
+	} else if (synchronous || (sis->flags & SWP_SYNCHRONOUS_IO)) {
+		swap_read_folio_bdev_sync(folio, sis);
 	} else {
-		return __set_page_dirty_no_writeback(page);
+		swap_read_folio_bdev_async(folio, sis);
 	}
+
+	if (workingset) {
+		delayacct_thrashing_end(&in_thrashing);
+		psi_memstall_leave(&pflags);
+	}
+	delayacct_swapin_end();
+}
+
+void __swap_read_unplug(struct swap_iocb *sio)
+{
+	struct iov_iter from;
+	struct address_space *mapping = sio->iocb.ki_filp->f_mapping;
+	int ret;
+
+	iov_iter_bvec(&from, ITER_DEST, sio->bvec, sio->pages, sio->len);
+	ret = mapping->a_ops->swap_rw(&sio->iocb, &from);
+	if (ret != -EIOCBQUEUED)
+		sio_read_complete(&sio->iocb, ret);
 }