extfat: remove ->writepage
[linux-block.git] / fs / exfat / inode.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
4  */
5
6 #include <linux/init.h>
7 #include <linux/buffer_head.h>
8 #include <linux/mpage.h>
9 #include <linux/bio.h>
10 #include <linux/blkdev.h>
11 #include <linux/time.h>
12 #include <linux/writeback.h>
13 #include <linux/uio.h>
14 #include <linux/random.h>
15 #include <linux/iversion.h>
16
17 #include "exfat_raw.h"
18 #include "exfat_fs.h"
19
20 int __exfat_write_inode(struct inode *inode, int sync)
21 {
22         unsigned long long on_disk_size;
23         struct exfat_dentry *ep, *ep2;
24         struct exfat_entry_set_cache *es = NULL;
25         struct super_block *sb = inode->i_sb;
26         struct exfat_sb_info *sbi = EXFAT_SB(sb);
27         struct exfat_inode_info *ei = EXFAT_I(inode);
28         bool is_dir = (ei->type == TYPE_DIR) ? true : false;
29
30         if (inode->i_ino == EXFAT_ROOT_INO)
31                 return 0;
32
33         /*
34          * If the inode is already unlinked, there is no need for updating it.
35          */
36         if (ei->dir.dir == DIR_DELETED)
37                 return 0;
38
39         if (is_dir && ei->dir.dir == sbi->root_dir && ei->entry == -1)
40                 return 0;
41
42         exfat_set_volume_dirty(sb);
43
44         /* get the directory entry of given file or directory */
45         es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES);
46         if (!es)
47                 return -EIO;
48         ep = exfat_get_dentry_cached(es, 0);
49         ep2 = exfat_get_dentry_cached(es, 1);
50
51         ep->dentry.file.attr = cpu_to_le16(exfat_make_attr(inode));
52
53         /* set FILE_INFO structure using the acquired struct exfat_dentry */
54         exfat_set_entry_time(sbi, &ei->i_crtime,
55                         &ep->dentry.file.create_tz,
56                         &ep->dentry.file.create_time,
57                         &ep->dentry.file.create_date,
58                         &ep->dentry.file.create_time_cs);
59         exfat_set_entry_time(sbi, &inode->i_mtime,
60                         &ep->dentry.file.modify_tz,
61                         &ep->dentry.file.modify_time,
62                         &ep->dentry.file.modify_date,
63                         &ep->dentry.file.modify_time_cs);
64         exfat_set_entry_time(sbi, &inode->i_atime,
65                         &ep->dentry.file.access_tz,
66                         &ep->dentry.file.access_time,
67                         &ep->dentry.file.access_date,
68                         NULL);
69
70         /* File size should be zero if there is no cluster allocated */
71         on_disk_size = i_size_read(inode);
72
73         if (ei->start_clu == EXFAT_EOF_CLUSTER)
74                 on_disk_size = 0;
75
76         ep2->dentry.stream.valid_size = cpu_to_le64(on_disk_size);
77         ep2->dentry.stream.size = ep2->dentry.stream.valid_size;
78         if (on_disk_size) {
79                 ep2->dentry.stream.flags = ei->flags;
80                 ep2->dentry.stream.start_clu = cpu_to_le32(ei->start_clu);
81         } else {
82                 ep2->dentry.stream.flags = ALLOC_FAT_CHAIN;
83                 ep2->dentry.stream.start_clu = EXFAT_FREE_CLUSTER;
84         }
85
86         exfat_update_dir_chksum_with_entry_set(es);
87         return exfat_free_dentry_set(es, sync);
88 }
89
90 int exfat_write_inode(struct inode *inode, struct writeback_control *wbc)
91 {
92         int ret;
93
94         mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
95         ret = __exfat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
96         mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
97
98         return ret;
99 }
100
101 void exfat_sync_inode(struct inode *inode)
102 {
103         lockdep_assert_held(&EXFAT_SB(inode->i_sb)->s_lock);
104         __exfat_write_inode(inode, 1);
105 }
106
107 /*
108  * Input: inode, (logical) clu_offset, target allocation area
109  * Output: errcode, cluster number
110  * *clu = (~0), if it's unable to allocate a new cluster
111  */
112 static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset,
113                 unsigned int *clu, int create)
114 {
115         int ret;
116         unsigned int last_clu;
117         struct exfat_chain new_clu;
118         struct super_block *sb = inode->i_sb;
119         struct exfat_sb_info *sbi = EXFAT_SB(sb);
120         struct exfat_inode_info *ei = EXFAT_I(inode);
121         unsigned int local_clu_offset = clu_offset;
122         unsigned int num_to_be_allocated = 0, num_clusters = 0;
123
124         if (ei->i_size_ondisk > 0)
125                 num_clusters =
126                         EXFAT_B_TO_CLU_ROUND_UP(ei->i_size_ondisk, sbi);
127
128         if (clu_offset >= num_clusters)
129                 num_to_be_allocated = clu_offset - num_clusters + 1;
130
131         if (!create && (num_to_be_allocated > 0)) {
132                 *clu = EXFAT_EOF_CLUSTER;
133                 return 0;
134         }
135
136         *clu = last_clu = ei->start_clu;
137
138         if (ei->flags == ALLOC_NO_FAT_CHAIN) {
139                 if (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
140                         last_clu += clu_offset - 1;
141
142                         if (clu_offset == num_clusters)
143                                 *clu = EXFAT_EOF_CLUSTER;
144                         else
145                                 *clu += clu_offset;
146                 }
147         } else if (ei->type == TYPE_FILE) {
148                 unsigned int fclus = 0;
149                 int err = exfat_get_cluster(inode, clu_offset,
150                                 &fclus, clu, &last_clu, 1);
151                 if (err)
152                         return -EIO;
153
154                 clu_offset -= fclus;
155         } else {
156                 /* hint information */
157                 if (clu_offset > 0 && ei->hint_bmap.off != EXFAT_EOF_CLUSTER &&
158                     ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) {
159                         clu_offset -= ei->hint_bmap.off;
160                         /* hint_bmap.clu should be valid */
161                         WARN_ON(ei->hint_bmap.clu < 2);
162                         *clu = ei->hint_bmap.clu;
163                 }
164
165                 while (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
166                         last_clu = *clu;
167                         if (exfat_get_next_cluster(sb, clu))
168                                 return -EIO;
169                         clu_offset--;
170                 }
171         }
172
173         if (*clu == EXFAT_EOF_CLUSTER) {
174                 exfat_set_volume_dirty(sb);
175
176                 new_clu.dir = (last_clu == EXFAT_EOF_CLUSTER) ?
177                                 EXFAT_EOF_CLUSTER : last_clu + 1;
178                 new_clu.size = 0;
179                 new_clu.flags = ei->flags;
180
181                 /* allocate a cluster */
182                 if (num_to_be_allocated < 1) {
183                         /* Broken FAT (i_sze > allocated FAT) */
184                         exfat_fs_error(sb, "broken FAT chain.");
185                         return -EIO;
186                 }
187
188                 ret = exfat_alloc_cluster(inode, num_to_be_allocated, &new_clu,
189                                 inode_needs_sync(inode));
190                 if (ret)
191                         return ret;
192
193                 if (new_clu.dir == EXFAT_EOF_CLUSTER ||
194                     new_clu.dir == EXFAT_FREE_CLUSTER) {
195                         exfat_fs_error(sb,
196                                 "bogus cluster new allocated (last_clu : %u, new_clu : %u)",
197                                 last_clu, new_clu.dir);
198                         return -EIO;
199                 }
200
201                 /* append to the FAT chain */
202                 if (last_clu == EXFAT_EOF_CLUSTER) {
203                         if (new_clu.flags == ALLOC_FAT_CHAIN)
204                                 ei->flags = ALLOC_FAT_CHAIN;
205                         ei->start_clu = new_clu.dir;
206                 } else {
207                         if (new_clu.flags != ei->flags) {
208                                 /* no-fat-chain bit is disabled,
209                                  * so fat-chain should be synced with
210                                  * alloc-bitmap
211                                  */
212                                 exfat_chain_cont_cluster(sb, ei->start_clu,
213                                         num_clusters);
214                                 ei->flags = ALLOC_FAT_CHAIN;
215                         }
216                         if (new_clu.flags == ALLOC_FAT_CHAIN)
217                                 if (exfat_ent_set(sb, last_clu, new_clu.dir))
218                                         return -EIO;
219                 }
220
221                 num_clusters += num_to_be_allocated;
222                 *clu = new_clu.dir;
223
224                 inode->i_blocks +=
225                         num_to_be_allocated << sbi->sect_per_clus_bits;
226
227                 /*
228                  * Move *clu pointer along FAT chains (hole care) because the
229                  * caller of this function expect *clu to be the last cluster.
230                  * This only works when num_to_be_allocated >= 2,
231                  * *clu = (the first cluster of the allocated chain) =>
232                  * (the last cluster of ...)
233                  */
234                 if (ei->flags == ALLOC_NO_FAT_CHAIN) {
235                         *clu += num_to_be_allocated - 1;
236                 } else {
237                         while (num_to_be_allocated > 1) {
238                                 if (exfat_get_next_cluster(sb, clu))
239                                         return -EIO;
240                                 num_to_be_allocated--;
241                         }
242                 }
243
244         }
245
246         /* hint information */
247         ei->hint_bmap.off = local_clu_offset;
248         ei->hint_bmap.clu = *clu;
249
250         return 0;
251 }
252
253 static int exfat_map_new_buffer(struct exfat_inode_info *ei,
254                 struct buffer_head *bh, loff_t pos)
255 {
256         if (buffer_delay(bh) && pos > ei->i_size_aligned)
257                 return -EIO;
258         set_buffer_new(bh);
259
260         /*
261          * Adjust i_size_aligned if i_size_ondisk is bigger than it.
262          */
263         if (ei->i_size_ondisk > ei->i_size_aligned)
264                 ei->i_size_aligned = ei->i_size_ondisk;
265         return 0;
266 }
267
268 static int exfat_get_block(struct inode *inode, sector_t iblock,
269                 struct buffer_head *bh_result, int create)
270 {
271         struct exfat_inode_info *ei = EXFAT_I(inode);
272         struct super_block *sb = inode->i_sb;
273         struct exfat_sb_info *sbi = EXFAT_SB(sb);
274         unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
275         int err = 0;
276         unsigned long mapped_blocks = 0;
277         unsigned int cluster, sec_offset;
278         sector_t last_block;
279         sector_t phys = 0;
280         loff_t pos;
281
282         mutex_lock(&sbi->s_lock);
283         last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb);
284         if (iblock >= last_block && !create)
285                 goto done;
286
287         /* Is this block already allocated? */
288         err = exfat_map_cluster(inode, iblock >> sbi->sect_per_clus_bits,
289                         &cluster, create);
290         if (err) {
291                 if (err != -ENOSPC)
292                         exfat_fs_error_ratelimit(sb,
293                                 "failed to bmap (inode : %p iblock : %llu, err : %d)",
294                                 inode, (unsigned long long)iblock, err);
295                 goto unlock_ret;
296         }
297
298         if (cluster == EXFAT_EOF_CLUSTER)
299                 goto done;
300
301         /* sector offset in cluster */
302         sec_offset = iblock & (sbi->sect_per_clus - 1);
303
304         phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset;
305         mapped_blocks = sbi->sect_per_clus - sec_offset;
306         max_blocks = min(mapped_blocks, max_blocks);
307
308         /* Treat newly added block / cluster */
309         if (iblock < last_block)
310                 create = 0;
311
312         if (create || buffer_delay(bh_result)) {
313                 pos = EXFAT_BLK_TO_B((iblock + 1), sb);
314                 if (ei->i_size_ondisk < pos)
315                         ei->i_size_ondisk = pos;
316         }
317
318         if (create) {
319                 err = exfat_map_new_buffer(ei, bh_result, pos);
320                 if (err) {
321                         exfat_fs_error(sb,
322                                         "requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n",
323                                         pos, ei->i_size_aligned);
324                         goto unlock_ret;
325                 }
326         }
327
328         if (buffer_delay(bh_result))
329                 clear_buffer_delay(bh_result);
330         map_bh(bh_result, sb, phys);
331 done:
332         bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb);
333 unlock_ret:
334         mutex_unlock(&sbi->s_lock);
335         return err;
336 }
337
338 static int exfat_read_folio(struct file *file, struct folio *folio)
339 {
340         return mpage_read_folio(folio, exfat_get_block);
341 }
342
343 static void exfat_readahead(struct readahead_control *rac)
344 {
345         mpage_readahead(rac, exfat_get_block);
346 }
347
348 static int exfat_writepages(struct address_space *mapping,
349                 struct writeback_control *wbc)
350 {
351         return mpage_writepages(mapping, wbc, exfat_get_block);
352 }
353
354 static void exfat_write_failed(struct address_space *mapping, loff_t to)
355 {
356         struct inode *inode = mapping->host;
357
358         if (to > i_size_read(inode)) {
359                 truncate_pagecache(inode, i_size_read(inode));
360                 inode->i_mtime = inode->i_ctime = current_time(inode);
361                 exfat_truncate(inode, EXFAT_I(inode)->i_size_aligned);
362         }
363 }
364
365 static int exfat_write_begin(struct file *file, struct address_space *mapping,
366                 loff_t pos, unsigned int len,
367                 struct page **pagep, void **fsdata)
368 {
369         int ret;
370
371         *pagep = NULL;
372         ret = cont_write_begin(file, mapping, pos, len, pagep, fsdata,
373                                exfat_get_block,
374                                &EXFAT_I(mapping->host)->i_size_ondisk);
375
376         if (ret < 0)
377                 exfat_write_failed(mapping, pos+len);
378
379         return ret;
380 }
381
382 static int exfat_write_end(struct file *file, struct address_space *mapping,
383                 loff_t pos, unsigned int len, unsigned int copied,
384                 struct page *pagep, void *fsdata)
385 {
386         struct inode *inode = mapping->host;
387         struct exfat_inode_info *ei = EXFAT_I(inode);
388         int err;
389
390         err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
391
392         if (ei->i_size_aligned < i_size_read(inode)) {
393                 exfat_fs_error(inode->i_sb,
394                         "invalid size(size(%llu) > aligned(%llu)\n",
395                         i_size_read(inode), ei->i_size_aligned);
396                 return -EIO;
397         }
398
399         if (err < len)
400                 exfat_write_failed(mapping, pos+len);
401
402         if (!(err < 0) && !(ei->attr & ATTR_ARCHIVE)) {
403                 inode->i_mtime = inode->i_ctime = current_time(inode);
404                 ei->attr |= ATTR_ARCHIVE;
405                 mark_inode_dirty(inode);
406         }
407
408         return err;
409 }
410
411 static ssize_t exfat_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
412 {
413         struct address_space *mapping = iocb->ki_filp->f_mapping;
414         struct inode *inode = mapping->host;
415         loff_t size = iocb->ki_pos + iov_iter_count(iter);
416         int rw = iov_iter_rw(iter);
417         ssize_t ret;
418
419         if (rw == WRITE) {
420                 /*
421                  * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
422                  * so we need to update the ->i_size_aligned to block boundary.
423                  *
424                  * But we must fill the remaining area or hole by nul for
425                  * updating ->i_size_aligned
426                  *
427                  * Return 0, and fallback to normal buffered write.
428                  */
429                 if (EXFAT_I(inode)->i_size_aligned < size)
430                         return 0;
431         }
432
433         /*
434          * Need to use the DIO_LOCKING for avoiding the race
435          * condition of exfat_get_block() and ->truncate().
436          */
437         ret = blockdev_direct_IO(iocb, inode, iter, exfat_get_block);
438         if (ret < 0 && (rw & WRITE))
439                 exfat_write_failed(mapping, size);
440         return ret;
441 }
442
443 static sector_t exfat_aop_bmap(struct address_space *mapping, sector_t block)
444 {
445         sector_t blocknr;
446
447         /* exfat_get_cluster() assumes the requested blocknr isn't truncated. */
448         down_read(&EXFAT_I(mapping->host)->truncate_lock);
449         blocknr = generic_block_bmap(mapping, block, exfat_get_block);
450         up_read(&EXFAT_I(mapping->host)->truncate_lock);
451         return blocknr;
452 }
453
454 /*
455  * exfat_block_truncate_page() zeroes out a mapping from file offset `from'
456  * up to the end of the block which corresponds to `from'.
457  * This is required during truncate to physically zeroout the tail end
458  * of that block so it doesn't yield old data if the file is later grown.
459  * Also, avoid causing failure from fsx for cases of "data past EOF"
460  */
461 int exfat_block_truncate_page(struct inode *inode, loff_t from)
462 {
463         return block_truncate_page(inode->i_mapping, from, exfat_get_block);
464 }
465
466 static const struct address_space_operations exfat_aops = {
467         .dirty_folio    = block_dirty_folio,
468         .invalidate_folio = block_invalidate_folio,
469         .read_folio     = exfat_read_folio,
470         .readahead      = exfat_readahead,
471         .writepages     = exfat_writepages,
472         .write_begin    = exfat_write_begin,
473         .write_end      = exfat_write_end,
474         .direct_IO      = exfat_direct_IO,
475         .bmap           = exfat_aop_bmap,
476         .migrate_folio  = buffer_migrate_folio,
477 };
478
479 static inline unsigned long exfat_hash(loff_t i_pos)
480 {
481         return hash_32(i_pos, EXFAT_HASH_BITS);
482 }
483
484 void exfat_hash_inode(struct inode *inode, loff_t i_pos)
485 {
486         struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
487         struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
488
489         spin_lock(&sbi->inode_hash_lock);
490         EXFAT_I(inode)->i_pos = i_pos;
491         hlist_add_head(&EXFAT_I(inode)->i_hash_fat, head);
492         spin_unlock(&sbi->inode_hash_lock);
493 }
494
495 void exfat_unhash_inode(struct inode *inode)
496 {
497         struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
498
499         spin_lock(&sbi->inode_hash_lock);
500         hlist_del_init(&EXFAT_I(inode)->i_hash_fat);
501         EXFAT_I(inode)->i_pos = 0;
502         spin_unlock(&sbi->inode_hash_lock);
503 }
504
505 struct inode *exfat_iget(struct super_block *sb, loff_t i_pos)
506 {
507         struct exfat_sb_info *sbi = EXFAT_SB(sb);
508         struct exfat_inode_info *info;
509         struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
510         struct inode *inode = NULL;
511
512         spin_lock(&sbi->inode_hash_lock);
513         hlist_for_each_entry(info, head, i_hash_fat) {
514                 WARN_ON(info->vfs_inode.i_sb != sb);
515
516                 if (i_pos != info->i_pos)
517                         continue;
518                 inode = igrab(&info->vfs_inode);
519                 if (inode)
520                         break;
521         }
522         spin_unlock(&sbi->inode_hash_lock);
523         return inode;
524 }
525
526 /* doesn't deal with root inode */
527 static int exfat_fill_inode(struct inode *inode, struct exfat_dir_entry *info)
528 {
529         struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
530         struct exfat_inode_info *ei = EXFAT_I(inode);
531         loff_t size = info->size;
532
533         ei->dir = info->dir;
534         ei->entry = info->entry;
535         ei->attr = info->attr;
536         ei->start_clu = info->start_clu;
537         ei->flags = info->flags;
538         ei->type = info->type;
539
540         ei->version = 0;
541         ei->hint_stat.eidx = 0;
542         ei->hint_stat.clu = info->start_clu;
543         ei->hint_femp.eidx = EXFAT_HINT_NONE;
544         ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
545         ei->i_pos = 0;
546
547         inode->i_uid = sbi->options.fs_uid;
548         inode->i_gid = sbi->options.fs_gid;
549         inode_inc_iversion(inode);
550         inode->i_generation = get_random_u32();
551
552         if (info->attr & ATTR_SUBDIR) { /* directory */
553                 inode->i_generation &= ~1;
554                 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
555                 inode->i_op = &exfat_dir_inode_operations;
556                 inode->i_fop = &exfat_dir_operations;
557                 set_nlink(inode, info->num_subdirs);
558         } else { /* regular file */
559                 inode->i_generation |= 1;
560                 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
561                 inode->i_op = &exfat_file_inode_operations;
562                 inode->i_fop = &exfat_file_operations;
563                 inode->i_mapping->a_ops = &exfat_aops;
564                 inode->i_mapping->nrpages = 0;
565         }
566
567         i_size_write(inode, size);
568
569         /* ondisk and aligned size should be aligned with block size */
570         if (size & (inode->i_sb->s_blocksize - 1)) {
571                 size |= (inode->i_sb->s_blocksize - 1);
572                 size++;
573         }
574
575         ei->i_size_aligned = size;
576         ei->i_size_ondisk = size;
577
578         exfat_save_attr(inode, info->attr);
579
580         inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >>
581                                 inode->i_blkbits;
582         inode->i_mtime = info->mtime;
583         inode->i_ctime = info->mtime;
584         ei->i_crtime = info->crtime;
585         inode->i_atime = info->atime;
586
587         return 0;
588 }
589
590 struct inode *exfat_build_inode(struct super_block *sb,
591                 struct exfat_dir_entry *info, loff_t i_pos)
592 {
593         struct inode *inode;
594         int err;
595
596         inode = exfat_iget(sb, i_pos);
597         if (inode)
598                 goto out;
599         inode = new_inode(sb);
600         if (!inode) {
601                 inode = ERR_PTR(-ENOMEM);
602                 goto out;
603         }
604         inode->i_ino = iunique(sb, EXFAT_ROOT_INO);
605         inode_set_iversion(inode, 1);
606         err = exfat_fill_inode(inode, info);
607         if (err) {
608                 iput(inode);
609                 inode = ERR_PTR(err);
610                 goto out;
611         }
612         exfat_hash_inode(inode, i_pos);
613         insert_inode_hash(inode);
614 out:
615         return inode;
616 }
617
618 void exfat_evict_inode(struct inode *inode)
619 {
620         truncate_inode_pages(&inode->i_data, 0);
621
622         if (!inode->i_nlink) {
623                 i_size_write(inode, 0);
624                 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
625                 __exfat_truncate(inode, 0);
626                 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
627         }
628
629         invalidate_inode_buffers(inode);
630         clear_inode(inode);
631         exfat_cache_inval_inode(inode);
632         exfat_unhash_inode(inode);
633 }