1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/mm/page_io.c
4 *
5 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
6 *
7 * Swap reorganised 29.12.95,
8 * Asynchronous swapping added 30.12.95. Stephen Tweedie
9 * Removed race in async swapping. 14.4.1996. Bruno Haible
10 * Add swap of shared pages through the page cache. 20.2.1998. Stephen Tweedie
11 * Always use brw_page, life becomes simpler. 12 May 1998 Eric Biederman
12 */
13
14 #include <linux/mm.h>
15 #include <linux/kernel_stat.h>
16 #include <linux/gfp.h>
17 #include <linux/pagemap.h>
18 #include <linux/swap.h>
19 #include <linux/bio.h>
20 #include <linux/swapops.h>
21 #include <linux/writeback.h>
22 #include <linux/blkdev.h>
23 #include <linux/psi.h>
24 #include <linux/uio.h>
25 #include <linux/sched/task.h>
26 #include <linux/delayacct.h>
27 #include <linux/zswap.h>
28 #include "swap.h"
29
__end_swap_bio_write(struct bio * bio)30 static void __end_swap_bio_write(struct bio *bio)
31 {
32 struct folio *folio = bio_first_folio_all(bio);
33
34 if (bio->bi_status) {
35 /*
36 * We failed to write the page out to swap-space.
37 * Re-dirty the page in order to avoid it being reclaimed.
38 * Also print a dire warning that things will go BAD (tm)
39 * very quickly.
40 *
41 * Also clear PG_reclaim to avoid folio_rotate_reclaimable()
42 */
43 folio_mark_dirty(folio);
44 pr_alert_ratelimited("Write-error on swap-device (%u:%u:%llu)\n",
45 MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
46 (unsigned long long)bio->bi_iter.bi_sector);
47 folio_clear_reclaim(folio);
48 }
49 folio_end_writeback(folio);
50 }
51
end_swap_bio_write(struct bio * bio)52 static void end_swap_bio_write(struct bio *bio)
53 {
54 __end_swap_bio_write(bio);
55 bio_put(bio);
56 }
57
__end_swap_bio_read(struct bio * bio)58 static void __end_swap_bio_read(struct bio *bio)
59 {
60 struct folio *folio = bio_first_folio_all(bio);
61
62 if (bio->bi_status) {
63 pr_alert_ratelimited("Read-error on swap-device (%u:%u:%llu)\n",
64 MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
65 (unsigned long long)bio->bi_iter.bi_sector);
66 } else {
67 folio_mark_uptodate(folio);
68 }
69 folio_unlock(folio);
70 }
71
end_swap_bio_read(struct bio * bio)72 static void end_swap_bio_read(struct bio *bio)
73 {
74 __end_swap_bio_read(bio);
75 bio_put(bio);
76 }
77
generic_swapfile_activate(struct swap_info_struct * sis,struct file * swap_file,sector_t * span)78 int generic_swapfile_activate(struct swap_info_struct *sis,
79 struct file *swap_file,
80 sector_t *span)
81 {
82 struct address_space *mapping = swap_file->f_mapping;
83 struct inode *inode = mapping->host;
84 unsigned blocks_per_page;
85 unsigned long page_no;
86 unsigned blkbits;
87 sector_t probe_block;
88 sector_t last_block;
89 sector_t lowest_block = -1;
90 sector_t highest_block = 0;
91 int nr_extents = 0;
92 int ret;
93
94 blkbits = inode->i_blkbits;
95 blocks_per_page = PAGE_SIZE >> blkbits;
96
97 /*
98 * Map all the blocks into the extent tree. This code doesn't try
99 * to be very smart.
100 */
101 probe_block = 0;
102 page_no = 0;
103 last_block = i_size_read(inode) >> blkbits;
104 while ((probe_block + blocks_per_page) <= last_block &&
105 page_no < sis->max) {
106 unsigned block_in_page;
107 sector_t first_block;
108
109 cond_resched();
110
111 first_block = probe_block;
112 ret = bmap(inode, &first_block);
113 if (ret || !first_block)
114 goto bad_bmap;
115
116 /*
117 * It must be PAGE_SIZE aligned on-disk
118 */
119 if (first_block & (blocks_per_page - 1)) {
120 probe_block++;
121 goto reprobe;
122 }
123
124 for (block_in_page = 1; block_in_page < blocks_per_page;
125 block_in_page++) {
126 sector_t block;
127
128 block = probe_block + block_in_page;
129 ret = bmap(inode, &block);
130 if (ret || !block)
131 goto bad_bmap;
132
133 if (block != first_block + block_in_page) {
134 /* Discontiguity */
135 probe_block++;
136 goto reprobe;
137 }
138 }
139
140 first_block >>= (PAGE_SHIFT - blkbits);
141 if (page_no) { /* exclude the header page */
142 if (first_block < lowest_block)
143 lowest_block = first_block;
144 if (first_block > highest_block)
145 highest_block = first_block;
146 }
147
148 /*
149 * We found a PAGE_SIZE-length, PAGE_SIZE-aligned run of blocks
150 */
151 ret = add_swap_extent(sis, page_no, 1, first_block);
152 if (ret < 0)
153 goto out;
154 nr_extents += ret;
155 page_no++;
156 probe_block += blocks_per_page;
157 reprobe:
158 continue;
159 }
160 ret = nr_extents;
161 *span = 1 + highest_block - lowest_block;
162 if (page_no == 0)
163 page_no = 1; /* force Empty message */
164 sis->max = page_no;
165 sis->pages = page_no - 1;
166 out:
167 return ret;
168 bad_bmap:
169 pr_err("swapon: swapfile has holes\n");
170 ret = -EINVAL;
171 goto out;
172 }
173
is_folio_zero_filled(struct folio * folio)174 static bool is_folio_zero_filled(struct folio *folio)
175 {
176 unsigned int pos, last_pos;
177 unsigned long *data;
178 unsigned int i;
179
180 last_pos = PAGE_SIZE / sizeof(*data) - 1;
181 for (i = 0; i < folio_nr_pages(folio); i++) {
182 data = kmap_local_folio(folio, i * PAGE_SIZE);
183 /*
184 * Check last word first, incase the page is zero-filled at
185 * the start and has non-zero data at the end, which is common
186 * in real-world workloads.
187 */
188 if (data[last_pos]) {
189 kunmap_local(data);
190 return false;
191 }
192 for (pos = 0; pos < last_pos; pos++) {
193 if (data[pos]) {
194 kunmap_local(data);
195 return false;
196 }
197 }
198 kunmap_local(data);
199 }
200
201 return true;
202 }
203
swap_zeromap_folio_set(struct folio * folio)204 static void swap_zeromap_folio_set(struct folio *folio)
205 {
206 struct obj_cgroup *objcg = get_obj_cgroup_from_folio(folio);
207 struct swap_info_struct *sis = __swap_entry_to_info(folio->swap);
208 int nr_pages = folio_nr_pages(folio);
209 swp_entry_t entry;
210 unsigned int i;
211
212 for (i = 0; i < folio_nr_pages(folio); i++) {
213 entry = page_swap_entry(folio_page(folio, i));
214 set_bit(swp_offset(entry), sis->zeromap);
215 }
216
217 count_vm_events(SWPOUT_ZERO, nr_pages);
218 if (objcg) {
219 count_objcg_events(objcg, SWPOUT_ZERO, nr_pages);
220 obj_cgroup_put(objcg);
221 }
222 }
223
swap_zeromap_folio_clear(struct folio * folio)224 static void swap_zeromap_folio_clear(struct folio *folio)
225 {
226 struct swap_info_struct *sis = __swap_entry_to_info(folio->swap);
227 swp_entry_t entry;
228 unsigned int i;
229
230 for (i = 0; i < folio_nr_pages(folio); i++) {
231 entry = page_swap_entry(folio_page(folio, i));
232 clear_bit(swp_offset(entry), sis->zeromap);
233 }
234 }
235
236 /*
237 * We may have stale swap cache pages in memory: notice
238 * them here and get rid of the unnecessary final write.
239 */
swap_writeout(struct folio * folio,struct swap_iocb ** swap_plug)240 int swap_writeout(struct folio *folio, struct swap_iocb **swap_plug)
241 {
242 int ret = 0;
243
244 if (folio_free_swap(folio))
245 goto out_unlock;
246
247 /*
248 * Arch code may have to preserve more data than just the page
249 * contents, e.g. memory tags.
250 */
251 ret = arch_prepare_to_swap(folio);
252 if (ret) {
253 folio_mark_dirty(folio);
254 goto out_unlock;
255 }
256
257 /*
258 * Use a bitmap (zeromap) to avoid doing IO for zero-filled pages.
259 * The bits in zeromap are protected by the locked swapcache folio
260 * and atomic updates are used to protect against read-modify-write
261 * corruption due to other zero swap entries seeing concurrent updates.
262 */
263 if (is_folio_zero_filled(folio)) {
264 swap_zeromap_folio_set(folio);
265 goto out_unlock;
266 }
267
268 /*
269 * Clear bits this folio occupies in the zeromap to prevent zero data
270 * being read in from any previous zero writes that occupied the same
271 * swap entries.
272 */
273 swap_zeromap_folio_clear(folio);
274
275 if (zswap_store(folio)) {
276 count_mthp_stat(folio_order(folio), MTHP_STAT_ZSWPOUT);
277 goto out_unlock;
278 }
279
280 rcu_read_lock();
281 if (!mem_cgroup_zswap_writeback_enabled(folio_memcg(folio))) {
282 rcu_read_unlock();
283 folio_mark_dirty(folio);
284 return AOP_WRITEPAGE_ACTIVATE;
285 }
286 rcu_read_unlock();
287
288 __swap_writepage(folio, swap_plug);
289 return 0;
290 out_unlock:
291 folio_unlock(folio);
292 return ret;
293 }
294
count_swpout_vm_event(struct folio * folio)295 static inline void count_swpout_vm_event(struct folio *folio)
296 {
297 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
298 if (unlikely(folio_test_pmd_mappable(folio))) {
299 count_memcg_folio_events(folio, THP_SWPOUT, 1);
300 count_vm_event(THP_SWPOUT);
301 }
302 #endif
303 count_mthp_stat(folio_order(folio), MTHP_STAT_SWPOUT);
304 count_memcg_folio_events(folio, PSWPOUT, folio_nr_pages(folio));
305 count_vm_events(PSWPOUT, folio_nr_pages(folio));
306 }
307
308 #if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
bio_associate_blkg_from_page(struct bio * bio,struct folio * folio)309 static void bio_associate_blkg_from_page(struct bio *bio, struct folio *folio)
310 {
311 struct cgroup_subsys_state *css;
312 struct mem_cgroup *memcg;
313
314 if (!folio_memcg_charged(folio))
315 return;
316
317 rcu_read_lock();
318 memcg = folio_memcg(folio);
319 css = cgroup_e_css(memcg->css.cgroup, &io_cgrp_subsys);
320 bio_associate_blkg_from_css(bio, css);
321 rcu_read_unlock();
322 }
323 #else
324 #define bio_associate_blkg_from_page(bio, folio) do { } while (0)
325 #endif /* CONFIG_MEMCG && CONFIG_BLK_CGROUP */
326
327 struct swap_iocb {
328 struct kiocb iocb;
329 struct bio_vec bvec[SWAP_CLUSTER_MAX];
330 int pages;
331 int len;
332 };
333 static mempool_t *sio_pool;
334
sio_pool_init(void)335 int sio_pool_init(void)
336 {
337 if (!sio_pool) {
338 mempool_t *pool = mempool_create_kmalloc_pool(
339 SWAP_CLUSTER_MAX, sizeof(struct swap_iocb));
340 if (cmpxchg(&sio_pool, NULL, pool))
341 mempool_destroy(pool);
342 }
343 if (!sio_pool)
344 return -ENOMEM;
345 return 0;
346 }
347
sio_write_complete(struct kiocb * iocb,long ret)348 static void sio_write_complete(struct kiocb *iocb, long ret)
349 {
350 struct swap_iocb *sio = container_of(iocb, struct swap_iocb, iocb);
351 struct page *page = sio->bvec[0].bv_page;
352 int p;
353
354 if (ret != sio->len) {
355 /*
356 * In the case of swap-over-nfs, this can be a
357 * temporary failure if the system has limited
358 * memory for allocating transmit buffers.
359 * Mark the page dirty and avoid
360 * folio_rotate_reclaimable but rate-limit the
361 * messages.
362 */
363 pr_err_ratelimited("Write error %ld on dio swapfile (%llu)\n",
364 ret, swap_dev_pos(page_swap_entry(page)));
365 for (p = 0; p < sio->pages; p++) {
366 page = sio->bvec[p].bv_page;
367 set_page_dirty(page);
368 ClearPageReclaim(page);
369 }
370 }
371
372 for (p = 0; p < sio->pages; p++)
373 end_page_writeback(sio->bvec[p].bv_page);
374
375 mempool_free(sio, sio_pool);
376 }
377
swap_writepage_fs(struct folio * folio,struct swap_iocb ** swap_plug)378 static void swap_writepage_fs(struct folio *folio, struct swap_iocb **swap_plug)
379 {
380 struct swap_iocb *sio = swap_plug ? *swap_plug : NULL;
381 struct swap_info_struct *sis = __swap_entry_to_info(folio->swap);
382 struct file *swap_file = sis->swap_file;
383 loff_t pos = swap_dev_pos(folio->swap);
384
385 count_swpout_vm_event(folio);
386 folio_start_writeback(folio);
387 folio_unlock(folio);
388 if (sio) {
389 if (sio->iocb.ki_filp != swap_file ||
390 sio->iocb.ki_pos + sio->len != pos) {
391 swap_write_unplug(sio);
392 sio = NULL;
393 }
394 }
395 if (!sio) {
396 sio = mempool_alloc(sio_pool, GFP_NOIO);
397 init_sync_kiocb(&sio->iocb, swap_file);
398 sio->iocb.ki_complete = sio_write_complete;
399 sio->iocb.ki_pos = pos;
400 sio->pages = 0;
401 sio->len = 0;
402 }
403 bvec_set_folio(&sio->bvec[sio->pages], folio, folio_size(folio), 0);
404 sio->len += folio_size(folio);
405 sio->pages += 1;
406 if (sio->pages == ARRAY_SIZE(sio->bvec) || !swap_plug) {
407 swap_write_unplug(sio);
408 sio = NULL;
409 }
410 if (swap_plug)
411 *swap_plug = sio;
412 }
413
swap_writepage_bdev_sync(struct folio * folio,struct swap_info_struct * sis)414 static void swap_writepage_bdev_sync(struct folio *folio,
415 struct swap_info_struct *sis)
416 {
417 struct bio_vec bv;
418 struct bio bio;
419
420 bio_init(&bio, sis->bdev, &bv, 1, REQ_OP_WRITE | REQ_SWAP);
421 bio.bi_iter.bi_sector = swap_folio_sector(folio);
422 bio_add_folio_nofail(&bio, folio, folio_size(folio), 0);
423
424 bio_associate_blkg_from_page(&bio, folio);
425 count_swpout_vm_event(folio);
426
427 folio_start_writeback(folio);
428 folio_unlock(folio);
429
430 submit_bio_wait(&bio);
431 __end_swap_bio_write(&bio);
432 }
433
swap_writepage_bdev_async(struct folio * folio,struct swap_info_struct * sis)434 static void swap_writepage_bdev_async(struct folio *folio,
435 struct swap_info_struct *sis)
436 {
437 struct bio *bio;
438
439 bio = bio_alloc(sis->bdev, 1, REQ_OP_WRITE | REQ_SWAP, GFP_NOIO);
440 bio->bi_iter.bi_sector = swap_folio_sector(folio);
441 bio->bi_end_io = end_swap_bio_write;
442 bio_add_folio_nofail(bio, folio, folio_size(folio), 0);
443
444 bio_associate_blkg_from_page(bio, folio);
445 count_swpout_vm_event(folio);
446 folio_start_writeback(folio);
447 folio_unlock(folio);
448 submit_bio(bio);
449 }
450
__swap_writepage(struct folio * folio,struct swap_iocb ** swap_plug)451 void __swap_writepage(struct folio *folio, struct swap_iocb **swap_plug)
452 {
453 struct swap_info_struct *sis = __swap_entry_to_info(folio->swap);
454
455 VM_BUG_ON_FOLIO(!folio_test_swapcache(folio), folio);
456 /*
457 * ->flags can be updated non-atomically,
458 * but that will never affect SWP_FS_OPS, so the data_race
459 * is safe.
460 */
461 if (data_race(sis->flags & SWP_FS_OPS))
462 swap_writepage_fs(folio, swap_plug);
463 /*
464 * ->flags can be updated non-atomically,
465 * but that will never affect SWP_SYNCHRONOUS_IO, so the data_race
466 * is safe.
467 */
468 else if (data_race(sis->flags & SWP_SYNCHRONOUS_IO))
469 swap_writepage_bdev_sync(folio, sis);
470 else
471 swap_writepage_bdev_async(folio, sis);
472 }
473
swap_write_unplug(struct swap_iocb * sio)474 void swap_write_unplug(struct swap_iocb *sio)
475 {
476 struct iov_iter from;
477 struct address_space *mapping = sio->iocb.ki_filp->f_mapping;
478 int ret;
479
480 iov_iter_bvec(&from, ITER_SOURCE, sio->bvec, sio->pages, sio->len);
481 ret = mapping->a_ops->swap_rw(&sio->iocb, &from);
482 if (ret != -EIOCBQUEUED)
483 sio_write_complete(&sio->iocb, ret);
484 }
485
sio_read_complete(struct kiocb * iocb,long ret)486 static void sio_read_complete(struct kiocb *iocb, long ret)
487 {
488 struct swap_iocb *sio = container_of(iocb, struct swap_iocb, iocb);
489 int p;
490
491 if (ret == sio->len) {
492 for (p = 0; p < sio->pages; p++) {
493 struct folio *folio = page_folio(sio->bvec[p].bv_page);
494
495 count_mthp_stat(folio_order(folio), MTHP_STAT_SWPIN);
496 count_memcg_folio_events(folio, PSWPIN, folio_nr_pages(folio));
497 folio_mark_uptodate(folio);
498 folio_unlock(folio);
499 }
500 count_vm_events(PSWPIN, sio->len >> PAGE_SHIFT);
501 } else {
502 for (p = 0; p < sio->pages; p++) {
503 struct folio *folio = page_folio(sio->bvec[p].bv_page);
504
505 folio_unlock(folio);
506 }
507 pr_alert_ratelimited("Read-error on swap-device\n");
508 }
509 mempool_free(sio, sio_pool);
510 }
511
swap_read_folio_zeromap(struct folio * folio)512 static bool swap_read_folio_zeromap(struct folio *folio)
513 {
514 int nr_pages = folio_nr_pages(folio);
515 struct obj_cgroup *objcg;
516 bool is_zeromap;
517
518 /*
519 * Swapping in a large folio that is partially in the zeromap is not
520 * currently handled. Return true without marking the folio uptodate so
521 * that an IO error is emitted (e.g. do_swap_page() will sigbus).
522 */
523 if (WARN_ON_ONCE(swap_zeromap_batch(folio->swap, nr_pages,
524 &is_zeromap) != nr_pages))
525 return true;
526
527 if (!is_zeromap)
528 return false;
529
530 objcg = get_obj_cgroup_from_folio(folio);
531 count_vm_events(SWPIN_ZERO, nr_pages);
532 if (objcg) {
533 count_objcg_events(objcg, SWPIN_ZERO, nr_pages);
534 obj_cgroup_put(objcg);
535 }
536
537 folio_zero_range(folio, 0, folio_size(folio));
538 folio_mark_uptodate(folio);
539 return true;
540 }
541
swap_read_folio_fs(struct folio * folio,struct swap_iocb ** plug)542 static void swap_read_folio_fs(struct folio *folio, struct swap_iocb **plug)
543 {
544 struct swap_info_struct *sis = __swap_entry_to_info(folio->swap);
545 struct swap_iocb *sio = NULL;
546 loff_t pos = swap_dev_pos(folio->swap);
547
548 if (plug)
549 sio = *plug;
550 if (sio) {
551 if (sio->iocb.ki_filp != sis->swap_file ||
552 sio->iocb.ki_pos + sio->len != pos) {
553 swap_read_unplug(sio);
554 sio = NULL;
555 }
556 }
557 if (!sio) {
558 sio = mempool_alloc(sio_pool, GFP_KERNEL);
559 init_sync_kiocb(&sio->iocb, sis->swap_file);
560 sio->iocb.ki_pos = pos;
561 sio->iocb.ki_complete = sio_read_complete;
562 sio->pages = 0;
563 sio->len = 0;
564 }
565 bvec_set_folio(&sio->bvec[sio->pages], folio, folio_size(folio), 0);
566 sio->len += folio_size(folio);
567 sio->pages += 1;
568 if (sio->pages == ARRAY_SIZE(sio->bvec) || !plug) {
569 swap_read_unplug(sio);
570 sio = NULL;
571 }
572 if (plug)
573 *plug = sio;
574 }
575
swap_read_folio_bdev_sync(struct folio * folio,struct swap_info_struct * sis)576 static void swap_read_folio_bdev_sync(struct folio *folio,
577 struct swap_info_struct *sis)
578 {
579 struct bio_vec bv;
580 struct bio bio;
581
582 bio_init(&bio, sis->bdev, &bv, 1, REQ_OP_READ);
583 bio.bi_iter.bi_sector = swap_folio_sector(folio);
584 bio_add_folio_nofail(&bio, folio, folio_size(folio), 0);
585 /*
586 * Keep this task valid during swap readpage because the oom killer may
587 * attempt to access it in the page fault retry time check.
588 */
589 get_task_struct(current);
590 count_mthp_stat(folio_order(folio), MTHP_STAT_SWPIN);
591 count_memcg_folio_events(folio, PSWPIN, folio_nr_pages(folio));
592 count_vm_events(PSWPIN, folio_nr_pages(folio));
593 submit_bio_wait(&bio);
594 __end_swap_bio_read(&bio);
595 put_task_struct(current);
596 }
597
swap_read_folio_bdev_async(struct folio * folio,struct swap_info_struct * sis)598 static void swap_read_folio_bdev_async(struct folio *folio,
599 struct swap_info_struct *sis)
600 {
601 struct bio *bio;
602
603 bio = bio_alloc(sis->bdev, 1, REQ_OP_READ, GFP_KERNEL);
604 bio->bi_iter.bi_sector = swap_folio_sector(folio);
605 bio->bi_end_io = end_swap_bio_read;
606 bio_add_folio_nofail(bio, folio, folio_size(folio), 0);
607 count_mthp_stat(folio_order(folio), MTHP_STAT_SWPIN);
608 count_memcg_folio_events(folio, PSWPIN, folio_nr_pages(folio));
609 count_vm_events(PSWPIN, folio_nr_pages(folio));
610 submit_bio(bio);
611 }
612
swap_read_folio(struct folio * folio,struct swap_iocb ** plug)613 void swap_read_folio(struct folio *folio, struct swap_iocb **plug)
614 {
615 struct swap_info_struct *sis = __swap_entry_to_info(folio->swap);
616 bool synchronous = sis->flags & SWP_SYNCHRONOUS_IO;
617 bool workingset = folio_test_workingset(folio);
618 unsigned long pflags;
619 bool in_thrashing;
620
621 VM_BUG_ON_FOLIO(!folio_test_swapcache(folio) && !synchronous, folio);
622 VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
623 VM_BUG_ON_FOLIO(folio_test_uptodate(folio), folio);
624
625 /*
626 * Count submission time as memory stall and delay. When the device
627 * is congested, or the submitting cgroup IO-throttled, submission
628 * can be a significant part of overall IO time.
629 */
630 if (workingset) {
631 delayacct_thrashing_start(&in_thrashing);
632 psi_memstall_enter(&pflags);
633 }
634 delayacct_swapin_start();
635
636 if (swap_read_folio_zeromap(folio)) {
637 folio_unlock(folio);
638 goto finish;
639 }
640
641 if (zswap_load(folio) != -ENOENT)
642 goto finish;
643
644 /* We have to read from slower devices. Increase zswap protection. */
645 zswap_folio_swapin(folio);
646
647 if (data_race(sis->flags & SWP_FS_OPS)) {
648 swap_read_folio_fs(folio, plug);
649 } else if (synchronous) {
650 swap_read_folio_bdev_sync(folio, sis);
651 } else {
652 swap_read_folio_bdev_async(folio, sis);
653 }
654
655 finish:
656 if (workingset) {
657 delayacct_thrashing_end(&in_thrashing);
658 psi_memstall_leave(&pflags);
659 }
660 delayacct_swapin_end();
661 }
662
__swap_read_unplug(struct swap_iocb * sio)663 void __swap_read_unplug(struct swap_iocb *sio)
664 {
665 struct iov_iter from;
666 struct address_space *mapping = sio->iocb.ki_filp->f_mapping;
667 int ret;
668
669 iov_iter_bvec(&from, ITER_DEST, sio->bvec, sio->pages, sio->len);
670 ret = mapping->a_ops->swap_rw(&sio->iocb, &from);
671 if (ret != -EIOCBQUEUED)
672 sio_read_complete(&sio->iocb, ret);
673 }
674