usb: dwc3: host: Set XHCI_SG_TRB_CACHE_SIZE_QUIRK
[platform/kernel/linux-rpi.git] / mm / page_io.c
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
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
52 static void end_swap_bio_write(struct bio *bio)
53 {
54         __end_swap_bio_write(bio);
55         bio_put(bio);
56 }
57
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
72 static void end_swap_bio_read(struct bio *bio)
73 {
74         __end_swap_bio_read(bio);
75         bio_put(bio);
76 }
77
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         sis->highest_bit = page_no - 1;
167 out:
168         return ret;
169 bad_bmap:
170         pr_err("swapon: swapfile has holes\n");
171         ret = -EINVAL;
172         goto out;
173 }
174
175 /*
176  * We may have stale swap cache pages in memory: notice
177  * them here and get rid of the unnecessary final write.
178  */
179 int swap_writepage(struct page *page, struct writeback_control *wbc)
180 {
181         struct folio *folio = page_folio(page);
182         int ret;
183
184         if (folio_free_swap(folio)) {
185                 folio_unlock(folio);
186                 return 0;
187         }
188         /*
189          * Arch code may have to preserve more data than just the page
190          * contents, e.g. memory tags.
191          */
192         ret = arch_prepare_to_swap(&folio->page);
193         if (ret) {
194                 folio_mark_dirty(folio);
195                 folio_unlock(folio);
196                 return ret;
197         }
198         if (zswap_store(folio)) {
199                 folio_start_writeback(folio);
200                 folio_unlock(folio);
201                 folio_end_writeback(folio);
202                 return 0;
203         }
204         __swap_writepage(&folio->page, wbc);
205         return 0;
206 }
207
208 static inline void count_swpout_vm_event(struct folio *folio)
209 {
210 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
211         if (unlikely(folio_test_pmd_mappable(folio)))
212                 count_vm_event(THP_SWPOUT);
213 #endif
214         count_vm_events(PSWPOUT, folio_nr_pages(folio));
215 }
216
217 #if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
218 static void bio_associate_blkg_from_page(struct bio *bio, struct folio *folio)
219 {
220         struct cgroup_subsys_state *css;
221         struct mem_cgroup *memcg;
222
223         memcg = folio_memcg(folio);
224         if (!memcg)
225                 return;
226
227         rcu_read_lock();
228         css = cgroup_e_css(memcg->css.cgroup, &io_cgrp_subsys);
229         bio_associate_blkg_from_css(bio, css);
230         rcu_read_unlock();
231 }
232 #else
233 #define bio_associate_blkg_from_page(bio, folio)                do { } while (0)
234 #endif /* CONFIG_MEMCG && CONFIG_BLK_CGROUP */
235
236 struct swap_iocb {
237         struct kiocb            iocb;
238         struct bio_vec          bvec[SWAP_CLUSTER_MAX];
239         int                     pages;
240         int                     len;
241 };
242 static mempool_t *sio_pool;
243
244 int sio_pool_init(void)
245 {
246         if (!sio_pool) {
247                 mempool_t *pool = mempool_create_kmalloc_pool(
248                         SWAP_CLUSTER_MAX, sizeof(struct swap_iocb));
249                 if (cmpxchg(&sio_pool, NULL, pool))
250                         mempool_destroy(pool);
251         }
252         if (!sio_pool)
253                 return -ENOMEM;
254         return 0;
255 }
256
257 static void sio_write_complete(struct kiocb *iocb, long ret)
258 {
259         struct swap_iocb *sio = container_of(iocb, struct swap_iocb, iocb);
260         struct page *page = sio->bvec[0].bv_page;
261         int p;
262
263         if (ret != sio->len) {
264                 /*
265                  * In the case of swap-over-nfs, this can be a
266                  * temporary failure if the system has limited
267                  * memory for allocating transmit buffers.
268                  * Mark the page dirty and avoid
269                  * folio_rotate_reclaimable but rate-limit the
270                  * messages but do not flag PageError like
271                  * the normal direct-to-bio case as it could
272                  * be temporary.
273                  */
274                 pr_err_ratelimited("Write error %ld on dio swapfile (%llu)\n",
275                                    ret, page_file_offset(page));
276                 for (p = 0; p < sio->pages; p++) {
277                         page = sio->bvec[p].bv_page;
278                         set_page_dirty(page);
279                         ClearPageReclaim(page);
280                 }
281         } else {
282                 for (p = 0; p < sio->pages; p++)
283                         count_swpout_vm_event(page_folio(sio->bvec[p].bv_page));
284         }
285
286         for (p = 0; p < sio->pages; p++)
287                 end_page_writeback(sio->bvec[p].bv_page);
288
289         mempool_free(sio, sio_pool);
290 }
291
292 static void swap_writepage_fs(struct page *page, struct writeback_control *wbc)
293 {
294         struct swap_iocb *sio = NULL;
295         struct swap_info_struct *sis = page_swap_info(page);
296         struct file *swap_file = sis->swap_file;
297         loff_t pos = page_file_offset(page);
298
299         set_page_writeback(page);
300         unlock_page(page);
301         if (wbc->swap_plug)
302                 sio = *wbc->swap_plug;
303         if (sio) {
304                 if (sio->iocb.ki_filp != swap_file ||
305                     sio->iocb.ki_pos + sio->len != pos) {
306                         swap_write_unplug(sio);
307                         sio = NULL;
308                 }
309         }
310         if (!sio) {
311                 sio = mempool_alloc(sio_pool, GFP_NOIO);
312                 init_sync_kiocb(&sio->iocb, swap_file);
313                 sio->iocb.ki_complete = sio_write_complete;
314                 sio->iocb.ki_pos = pos;
315                 sio->pages = 0;
316                 sio->len = 0;
317         }
318         bvec_set_page(&sio->bvec[sio->pages], page, thp_size(page), 0);
319         sio->len += thp_size(page);
320         sio->pages += 1;
321         if (sio->pages == ARRAY_SIZE(sio->bvec) || !wbc->swap_plug) {
322                 swap_write_unplug(sio);
323                 sio = NULL;
324         }
325         if (wbc->swap_plug)
326                 *wbc->swap_plug = sio;
327 }
328
329 static void swap_writepage_bdev_sync(struct page *page,
330                 struct writeback_control *wbc, struct swap_info_struct *sis)
331 {
332         struct bio_vec bv;
333         struct bio bio;
334         struct folio *folio = page_folio(page);
335
336         bio_init(&bio, sis->bdev, &bv, 1,
337                  REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc));
338         bio.bi_iter.bi_sector = swap_page_sector(page);
339         __bio_add_page(&bio, page, thp_size(page), 0);
340
341         bio_associate_blkg_from_page(&bio, folio);
342         count_swpout_vm_event(folio);
343
344         folio_start_writeback(folio);
345         folio_unlock(folio);
346
347         submit_bio_wait(&bio);
348         __end_swap_bio_write(&bio);
349 }
350
351 static void swap_writepage_bdev_async(struct page *page,
352                 struct writeback_control *wbc, struct swap_info_struct *sis)
353 {
354         struct bio *bio;
355         struct folio *folio = page_folio(page);
356
357         bio = bio_alloc(sis->bdev, 1,
358                         REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc),
359                         GFP_NOIO);
360         bio->bi_iter.bi_sector = swap_page_sector(page);
361         bio->bi_end_io = end_swap_bio_write;
362         __bio_add_page(bio, page, thp_size(page), 0);
363
364         bio_associate_blkg_from_page(bio, folio);
365         count_swpout_vm_event(folio);
366         folio_start_writeback(folio);
367         folio_unlock(folio);
368         submit_bio(bio);
369 }
370
371 void __swap_writepage(struct page *page, struct writeback_control *wbc)
372 {
373         struct swap_info_struct *sis = page_swap_info(page);
374
375         VM_BUG_ON_PAGE(!PageSwapCache(page), page);
376         /*
377          * ->flags can be updated non-atomicially (scan_swap_map_slots),
378          * but that will never affect SWP_FS_OPS, so the data_race
379          * is safe.
380          */
381         if (data_race(sis->flags & SWP_FS_OPS))
382                 swap_writepage_fs(page, wbc);
383         else if (sis->flags & SWP_SYNCHRONOUS_IO)
384                 swap_writepage_bdev_sync(page, wbc, sis);
385         else
386                 swap_writepage_bdev_async(page, wbc, sis);
387 }
388
389 void swap_write_unplug(struct swap_iocb *sio)
390 {
391         struct iov_iter from;
392         struct address_space *mapping = sio->iocb.ki_filp->f_mapping;
393         int ret;
394
395         iov_iter_bvec(&from, ITER_SOURCE, sio->bvec, sio->pages, sio->len);
396         ret = mapping->a_ops->swap_rw(&sio->iocb, &from);
397         if (ret != -EIOCBQUEUED)
398                 sio_write_complete(&sio->iocb, ret);
399 }
400
401 static void sio_read_complete(struct kiocb *iocb, long ret)
402 {
403         struct swap_iocb *sio = container_of(iocb, struct swap_iocb, iocb);
404         int p;
405
406         if (ret == sio->len) {
407                 for (p = 0; p < sio->pages; p++) {
408                         struct folio *folio = page_folio(sio->bvec[p].bv_page);
409
410                         folio_mark_uptodate(folio);
411                         folio_unlock(folio);
412                 }
413                 count_vm_events(PSWPIN, sio->pages);
414         } else {
415                 for (p = 0; p < sio->pages; p++) {
416                         struct folio *folio = page_folio(sio->bvec[p].bv_page);
417
418                         folio_unlock(folio);
419                 }
420                 pr_alert_ratelimited("Read-error on swap-device\n");
421         }
422         mempool_free(sio, sio_pool);
423 }
424
425 static void swap_readpage_fs(struct page *page,
426                              struct swap_iocb **plug)
427 {
428         struct swap_info_struct *sis = page_swap_info(page);
429         struct swap_iocb *sio = NULL;
430         loff_t pos = page_file_offset(page);
431
432         if (plug)
433                 sio = *plug;
434         if (sio) {
435                 if (sio->iocb.ki_filp != sis->swap_file ||
436                     sio->iocb.ki_pos + sio->len != pos) {
437                         swap_read_unplug(sio);
438                         sio = NULL;
439                 }
440         }
441         if (!sio) {
442                 sio = mempool_alloc(sio_pool, GFP_KERNEL);
443                 init_sync_kiocb(&sio->iocb, sis->swap_file);
444                 sio->iocb.ki_pos = pos;
445                 sio->iocb.ki_complete = sio_read_complete;
446                 sio->pages = 0;
447                 sio->len = 0;
448         }
449         bvec_set_page(&sio->bvec[sio->pages], page, thp_size(page), 0);
450         sio->len += thp_size(page);
451         sio->pages += 1;
452         if (sio->pages == ARRAY_SIZE(sio->bvec) || !plug) {
453                 swap_read_unplug(sio);
454                 sio = NULL;
455         }
456         if (plug)
457                 *plug = sio;
458 }
459
460 static void swap_readpage_bdev_sync(struct page *page,
461                 struct swap_info_struct *sis)
462 {
463         struct bio_vec bv;
464         struct bio bio;
465
466         bio_init(&bio, sis->bdev, &bv, 1, REQ_OP_READ);
467         bio.bi_iter.bi_sector = swap_page_sector(page);
468         __bio_add_page(&bio, page, thp_size(page), 0);
469         /*
470          * Keep this task valid during swap readpage because the oom killer may
471          * attempt to access it in the page fault retry time check.
472          */
473         get_task_struct(current);
474         count_vm_event(PSWPIN);
475         submit_bio_wait(&bio);
476         __end_swap_bio_read(&bio);
477         put_task_struct(current);
478 }
479
480 static void swap_readpage_bdev_async(struct page *page,
481                 struct swap_info_struct *sis)
482 {
483         struct bio *bio;
484
485         bio = bio_alloc(sis->bdev, 1, REQ_OP_READ, GFP_KERNEL);
486         bio->bi_iter.bi_sector = swap_page_sector(page);
487         bio->bi_end_io = end_swap_bio_read;
488         __bio_add_page(bio, page, thp_size(page), 0);
489         count_vm_event(PSWPIN);
490         submit_bio(bio);
491 }
492
493 void swap_readpage(struct page *page, bool synchronous, struct swap_iocb **plug)
494 {
495         struct folio *folio = page_folio(page);
496         struct swap_info_struct *sis = page_swap_info(page);
497         bool workingset = folio_test_workingset(folio);
498         unsigned long pflags;
499         bool in_thrashing;
500
501         VM_BUG_ON_FOLIO(!folio_test_swapcache(folio) && !synchronous, folio);
502         VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
503         VM_BUG_ON_FOLIO(folio_test_uptodate(folio), folio);
504
505         /*
506          * Count submission time as memory stall and delay. When the device
507          * is congested, or the submitting cgroup IO-throttled, submission
508          * can be a significant part of overall IO time.
509          */
510         if (workingset) {
511                 delayacct_thrashing_start(&in_thrashing);
512                 psi_memstall_enter(&pflags);
513         }
514         delayacct_swapin_start();
515
516         if (zswap_load(folio)) {
517                 folio_mark_uptodate(folio);
518                 folio_unlock(folio);
519         } else if (data_race(sis->flags & SWP_FS_OPS)) {
520                 swap_readpage_fs(page, plug);
521         } else if (synchronous || (sis->flags & SWP_SYNCHRONOUS_IO)) {
522                 swap_readpage_bdev_sync(page, sis);
523         } else {
524                 swap_readpage_bdev_async(page, sis);
525         }
526
527         if (workingset) {
528                 delayacct_thrashing_end(&in_thrashing);
529                 psi_memstall_leave(&pflags);
530         }
531         delayacct_swapin_end();
532 }
533
534 void __swap_read_unplug(struct swap_iocb *sio)
535 {
536         struct iov_iter from;
537         struct address_space *mapping = sio->iocb.ki_filp->f_mapping;
538         int ret;
539
540         iov_iter_bvec(&from, ITER_DEST, sio->bvec, sio->pages, sio->len);
541         ret = mapping->a_ops->swap_rw(&sio->iocb, &from);
542         if (ret != -EIOCBQUEUED)
543                 sio_read_complete(&sio->iocb, ret);
544 }