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TOMOYO Linux Cross Reference
Linux/fs/exfat/inode.c

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  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;
 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         struct timespec64 ts;
 30 
 31         if (inode->i_ino == EXFAT_ROOT_INO)
 32                 return 0;
 33 
 34         /*
 35          * If the inode is already unlinked, there is no need for updating it.
 36          */
 37         if (ei->dir.dir == DIR_DELETED)
 38                 return 0;
 39 
 40         if (is_dir && ei->dir.dir == sbi->root_dir && ei->entry == -1)
 41                 return 0;
 42 
 43         exfat_set_volume_dirty(sb);
 44 
 45         /* get the directory entry of given file or directory */
 46         if (exfat_get_dentry_set(&es, sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES))
 47                 return -EIO;
 48         ep = exfat_get_dentry_cached(&es, ES_IDX_FILE);
 49         ep2 = exfat_get_dentry_cached(&es, ES_IDX_STREAM);
 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         ts = inode_get_mtime(inode);
 60         exfat_set_entry_time(sbi, &ts,
 61                              &ep->dentry.file.modify_tz,
 62                              &ep->dentry.file.modify_time,
 63                              &ep->dentry.file.modify_date,
 64                              &ep->dentry.file.modify_time_cs);
 65         ts = inode_get_atime(inode);
 66         exfat_set_entry_time(sbi, &ts,
 67                              &ep->dentry.file.access_tz,
 68                              &ep->dentry.file.access_time,
 69                              &ep->dentry.file.access_date,
 70                              NULL);
 71 
 72         /* File size should be zero if there is no cluster allocated */
 73         on_disk_size = i_size_read(inode);
 74 
 75         if (ei->start_clu == EXFAT_EOF_CLUSTER)
 76                 on_disk_size = 0;
 77 
 78         ep2->dentry.stream.size = cpu_to_le64(on_disk_size);
 79         /*
 80          * mmap write does not use exfat_write_end(), valid_size may be
 81          * extended to the sector-aligned length in exfat_get_block().
 82          * So we need to fixup valid_size to the writren length.
 83          */
 84         if (on_disk_size < ei->valid_size)
 85                 ep2->dentry.stream.valid_size = ep2->dentry.stream.size;
 86         else
 87                 ep2->dentry.stream.valid_size = cpu_to_le64(ei->valid_size);
 88 
 89         if (on_disk_size) {
 90                 ep2->dentry.stream.flags = ei->flags;
 91                 ep2->dentry.stream.start_clu = cpu_to_le32(ei->start_clu);
 92         } else {
 93                 ep2->dentry.stream.flags = ALLOC_FAT_CHAIN;
 94                 ep2->dentry.stream.start_clu = EXFAT_FREE_CLUSTER;
 95         }
 96 
 97         exfat_update_dir_chksum(&es);
 98         return exfat_put_dentry_set(&es, sync);
 99 }
100 
101 int exfat_write_inode(struct inode *inode, struct writeback_control *wbc)
102 {
103         int ret;
104 
105         mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
106         ret = __exfat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
107         mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
108 
109         return ret;
110 }
111 
112 void exfat_sync_inode(struct inode *inode)
113 {
114         lockdep_assert_held(&EXFAT_SB(inode->i_sb)->s_lock);
115         __exfat_write_inode(inode, 1);
116 }
117 
118 /*
119  * Input: inode, (logical) clu_offset, target allocation area
120  * Output: errcode, cluster number
121  * *clu = (~0), if it's unable to allocate a new cluster
122  */
123 static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset,
124                 unsigned int *clu, int create)
125 {
126         int ret;
127         unsigned int last_clu;
128         struct exfat_chain new_clu;
129         struct super_block *sb = inode->i_sb;
130         struct exfat_sb_info *sbi = EXFAT_SB(sb);
131         struct exfat_inode_info *ei = EXFAT_I(inode);
132         unsigned int local_clu_offset = clu_offset;
133         unsigned int num_to_be_allocated = 0, num_clusters = 0;
134 
135         if (ei->i_size_ondisk > 0)
136                 num_clusters =
137                         EXFAT_B_TO_CLU_ROUND_UP(ei->i_size_ondisk, sbi);
138 
139         if (clu_offset >= num_clusters)
140                 num_to_be_allocated = clu_offset - num_clusters + 1;
141 
142         if (!create && (num_to_be_allocated > 0)) {
143                 *clu = EXFAT_EOF_CLUSTER;
144                 return 0;
145         }
146 
147         *clu = last_clu = ei->start_clu;
148 
149         if (ei->flags == ALLOC_NO_FAT_CHAIN) {
150                 if (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
151                         last_clu += clu_offset - 1;
152 
153                         if (clu_offset == num_clusters)
154                                 *clu = EXFAT_EOF_CLUSTER;
155                         else
156                                 *clu += clu_offset;
157                 }
158         } else if (ei->type == TYPE_FILE) {
159                 unsigned int fclus = 0;
160                 int err = exfat_get_cluster(inode, clu_offset,
161                                 &fclus, clu, &last_clu, 1);
162                 if (err)
163                         return -EIO;
164 
165                 clu_offset -= fclus;
166         } else {
167                 /* hint information */
168                 if (clu_offset > 0 && ei->hint_bmap.off != EXFAT_EOF_CLUSTER &&
169                     ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) {
170                         clu_offset -= ei->hint_bmap.off;
171                         /* hint_bmap.clu should be valid */
172                         WARN_ON(ei->hint_bmap.clu < 2);
173                         *clu = ei->hint_bmap.clu;
174                 }
175 
176                 while (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
177                         last_clu = *clu;
178                         if (exfat_get_next_cluster(sb, clu))
179                                 return -EIO;
180                         clu_offset--;
181                 }
182         }
183 
184         if (*clu == EXFAT_EOF_CLUSTER) {
185                 exfat_set_volume_dirty(sb);
186 
187                 new_clu.dir = (last_clu == EXFAT_EOF_CLUSTER) ?
188                                 EXFAT_EOF_CLUSTER : last_clu + 1;
189                 new_clu.size = 0;
190                 new_clu.flags = ei->flags;
191 
192                 /* allocate a cluster */
193                 if (num_to_be_allocated < 1) {
194                         /* Broken FAT (i_sze > allocated FAT) */
195                         exfat_fs_error(sb, "broken FAT chain.");
196                         return -EIO;
197                 }
198 
199                 ret = exfat_alloc_cluster(inode, num_to_be_allocated, &new_clu,
200                                 inode_needs_sync(inode));
201                 if (ret)
202                         return ret;
203 
204                 if (new_clu.dir == EXFAT_EOF_CLUSTER ||
205                     new_clu.dir == EXFAT_FREE_CLUSTER) {
206                         exfat_fs_error(sb,
207                                 "bogus cluster new allocated (last_clu : %u, new_clu : %u)",
208                                 last_clu, new_clu.dir);
209                         return -EIO;
210                 }
211 
212                 /* append to the FAT chain */
213                 if (last_clu == EXFAT_EOF_CLUSTER) {
214                         if (new_clu.flags == ALLOC_FAT_CHAIN)
215                                 ei->flags = ALLOC_FAT_CHAIN;
216                         ei->start_clu = new_clu.dir;
217                 } else {
218                         if (new_clu.flags != ei->flags) {
219                                 /* no-fat-chain bit is disabled,
220                                  * so fat-chain should be synced with
221                                  * alloc-bitmap
222                                  */
223                                 exfat_chain_cont_cluster(sb, ei->start_clu,
224                                         num_clusters);
225                                 ei->flags = ALLOC_FAT_CHAIN;
226                         }
227                         if (new_clu.flags == ALLOC_FAT_CHAIN)
228                                 if (exfat_ent_set(sb, last_clu, new_clu.dir))
229                                         return -EIO;
230                 }
231 
232                 num_clusters += num_to_be_allocated;
233                 *clu = new_clu.dir;
234 
235                 inode->i_blocks += EXFAT_CLU_TO_B(num_to_be_allocated, sbi) >> 9;
236 
237                 /*
238                  * Move *clu pointer along FAT chains (hole care) because the
239                  * caller of this function expect *clu to be the last cluster.
240                  * This only works when num_to_be_allocated >= 2,
241                  * *clu = (the first cluster of the allocated chain) =>
242                  * (the last cluster of ...)
243                  */
244                 if (ei->flags == ALLOC_NO_FAT_CHAIN) {
245                         *clu += num_to_be_allocated - 1;
246                 } else {
247                         while (num_to_be_allocated > 1) {
248                                 if (exfat_get_next_cluster(sb, clu))
249                                         return -EIO;
250                                 num_to_be_allocated--;
251                         }
252                 }
253 
254         }
255 
256         /* hint information */
257         ei->hint_bmap.off = local_clu_offset;
258         ei->hint_bmap.clu = *clu;
259 
260         return 0;
261 }
262 
263 static int exfat_map_new_buffer(struct exfat_inode_info *ei,
264                 struct buffer_head *bh, loff_t pos)
265 {
266         if (buffer_delay(bh) && pos > ei->i_size_aligned)
267                 return -EIO;
268         set_buffer_new(bh);
269 
270         /*
271          * Adjust i_size_aligned if i_size_ondisk is bigger than it.
272          */
273         if (ei->i_size_ondisk > ei->i_size_aligned)
274                 ei->i_size_aligned = ei->i_size_ondisk;
275         return 0;
276 }
277 
278 static int exfat_get_block(struct inode *inode, sector_t iblock,
279                 struct buffer_head *bh_result, int create)
280 {
281         struct exfat_inode_info *ei = EXFAT_I(inode);
282         struct super_block *sb = inode->i_sb;
283         struct exfat_sb_info *sbi = EXFAT_SB(sb);
284         unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
285         int err = 0;
286         unsigned long mapped_blocks = 0;
287         unsigned int cluster, sec_offset;
288         sector_t last_block;
289         sector_t phys = 0;
290         sector_t valid_blks;
291         loff_t pos;
292 
293         mutex_lock(&sbi->s_lock);
294         last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb);
295         if (iblock >= last_block && !create)
296                 goto done;
297 
298         /* Is this block already allocated? */
299         err = exfat_map_cluster(inode, iblock >> sbi->sect_per_clus_bits,
300                         &cluster, create);
301         if (err) {
302                 if (err != -ENOSPC)
303                         exfat_fs_error_ratelimit(sb,
304                                 "failed to bmap (inode : %p iblock : %llu, err : %d)",
305                                 inode, (unsigned long long)iblock, err);
306                 goto unlock_ret;
307         }
308 
309         if (cluster == EXFAT_EOF_CLUSTER)
310                 goto done;
311 
312         /* sector offset in cluster */
313         sec_offset = iblock & (sbi->sect_per_clus - 1);
314 
315         phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset;
316         mapped_blocks = sbi->sect_per_clus - sec_offset;
317         max_blocks = min(mapped_blocks, max_blocks);
318 
319         pos = EXFAT_BLK_TO_B((iblock + 1), sb);
320         if ((create && iblock >= last_block) || buffer_delay(bh_result)) {
321                 if (ei->i_size_ondisk < pos)
322                         ei->i_size_ondisk = pos;
323         }
324 
325         map_bh(bh_result, sb, phys);
326         if (buffer_delay(bh_result))
327                 clear_buffer_delay(bh_result);
328 
329         if (create) {
330                 valid_blks = EXFAT_B_TO_BLK_ROUND_UP(ei->valid_size, sb);
331 
332                 if (iblock + max_blocks < valid_blks) {
333                         /* The range has been written, map it */
334                         goto done;
335                 } else if (iblock < valid_blks) {
336                         /*
337                          * The range has been partially written,
338                          * map the written part.
339                          */
340                         max_blocks = valid_blks - iblock;
341                         goto done;
342                 }
343 
344                 /* The area has not been written, map and mark as new. */
345                 err = exfat_map_new_buffer(ei, bh_result, pos);
346                 if (err) {
347                         exfat_fs_error(sb,
348                                         "requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n",
349                                         pos, ei->i_size_aligned);
350                         goto unlock_ret;
351                 }
352 
353                 ei->valid_size = EXFAT_BLK_TO_B(iblock + max_blocks, sb);
354                 mark_inode_dirty(inode);
355         } else {
356                 valid_blks = EXFAT_B_TO_BLK(ei->valid_size, sb);
357 
358                 if (iblock + max_blocks < valid_blks) {
359                         /* The range has been written, map it */
360                         goto done;
361                 } else if (iblock < valid_blks) {
362                         /*
363                          * The area has been partially written,
364                          * map the written part.
365                          */
366                         max_blocks = valid_blks - iblock;
367                         goto done;
368                 } else if (iblock == valid_blks &&
369                            (ei->valid_size & (sb->s_blocksize - 1))) {
370                         /*
371                          * The block has been partially written,
372                          * zero the unwritten part and map the block.
373                          */
374                         loff_t size, off;
375 
376                         max_blocks = 1;
377 
378                         /*
379                          * For direct read, the unwritten part will be zeroed in
380                          * exfat_direct_IO()
381                          */
382                         if (!bh_result->b_folio)
383                                 goto done;
384 
385                         pos -= sb->s_blocksize;
386                         size = ei->valid_size - pos;
387                         off = pos & (PAGE_SIZE - 1);
388 
389                         folio_set_bh(bh_result, bh_result->b_folio, off);
390                         err = bh_read(bh_result, 0);
391                         if (err < 0)
392                                 goto unlock_ret;
393 
394                         folio_zero_segment(bh_result->b_folio, off + size,
395                                         off + sb->s_blocksize);
396                 } else {
397                         /*
398                          * The range has not been written, clear the mapped flag
399                          * to only zero the cache and do not read from disk.
400                          */
401                         clear_buffer_mapped(bh_result);
402                 }
403         }
404 done:
405         bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb);
406 unlock_ret:
407         mutex_unlock(&sbi->s_lock);
408         return err;
409 }
410 
411 static int exfat_read_folio(struct file *file, struct folio *folio)
412 {
413         return mpage_read_folio(folio, exfat_get_block);
414 }
415 
416 static void exfat_readahead(struct readahead_control *rac)
417 {
418         struct address_space *mapping = rac->mapping;
419         struct inode *inode = mapping->host;
420         struct exfat_inode_info *ei = EXFAT_I(inode);
421         loff_t pos = readahead_pos(rac);
422 
423         /* Range cross valid_size, read it page by page. */
424         if (ei->valid_size < i_size_read(inode) &&
425             pos <= ei->valid_size &&
426             ei->valid_size < pos + readahead_length(rac))
427                 return;
428 
429         mpage_readahead(rac, exfat_get_block);
430 }
431 
432 static int exfat_writepages(struct address_space *mapping,
433                 struct writeback_control *wbc)
434 {
435         return mpage_writepages(mapping, wbc, exfat_get_block);
436 }
437 
438 static void exfat_write_failed(struct address_space *mapping, loff_t to)
439 {
440         struct inode *inode = mapping->host;
441 
442         if (to > i_size_read(inode)) {
443                 truncate_pagecache(inode, i_size_read(inode));
444                 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
445                 exfat_truncate(inode);
446         }
447 }
448 
449 static int exfat_write_begin(struct file *file, struct address_space *mapping,
450                 loff_t pos, unsigned int len,
451                 struct page **pagep, void **fsdata)
452 {
453         int ret;
454 
455         *pagep = NULL;
456         ret = block_write_begin(mapping, pos, len, pagep, exfat_get_block);
457 
458         if (ret < 0)
459                 exfat_write_failed(mapping, pos+len);
460 
461         return ret;
462 }
463 
464 static int exfat_write_end(struct file *file, struct address_space *mapping,
465                 loff_t pos, unsigned int len, unsigned int copied,
466                 struct page *pagep, void *fsdata)
467 {
468         struct inode *inode = mapping->host;
469         struct exfat_inode_info *ei = EXFAT_I(inode);
470         int err;
471 
472         err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
473 
474         if (ei->i_size_aligned < i_size_read(inode)) {
475                 exfat_fs_error(inode->i_sb,
476                         "invalid size(size(%llu) > aligned(%llu)\n",
477                         i_size_read(inode), ei->i_size_aligned);
478                 return -EIO;
479         }
480 
481         if (err < len)
482                 exfat_write_failed(mapping, pos+len);
483 
484         if (!(err < 0) && pos + err > ei->valid_size) {
485                 ei->valid_size = pos + err;
486                 mark_inode_dirty(inode);
487         }
488 
489         if (!(err < 0) && !(ei->attr & EXFAT_ATTR_ARCHIVE)) {
490                 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
491                 ei->attr |= EXFAT_ATTR_ARCHIVE;
492                 mark_inode_dirty(inode);
493         }
494 
495         return err;
496 }
497 
498 static ssize_t exfat_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
499 {
500         struct address_space *mapping = iocb->ki_filp->f_mapping;
501         struct inode *inode = mapping->host;
502         struct exfat_inode_info *ei = EXFAT_I(inode);
503         loff_t pos = iocb->ki_pos;
504         loff_t size = pos + iov_iter_count(iter);
505         int rw = iov_iter_rw(iter);
506         ssize_t ret;
507 
508         if (rw == WRITE) {
509                 /*
510                  * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
511                  * so we need to update the ->i_size_aligned to block boundary.
512                  *
513                  * But we must fill the remaining area or hole by nul for
514                  * updating ->i_size_aligned
515                  *
516                  * Return 0, and fallback to normal buffered write.
517                  */
518                 if (EXFAT_I(inode)->i_size_aligned < size)
519                         return 0;
520         }
521 
522         /*
523          * Need to use the DIO_LOCKING for avoiding the race
524          * condition of exfat_get_block() and ->truncate().
525          */
526         ret = blockdev_direct_IO(iocb, inode, iter, exfat_get_block);
527         if (ret < 0) {
528                 if (rw == WRITE && ret != -EIOCBQUEUED)
529                         exfat_write_failed(mapping, size);
530 
531                 return ret;
532         } else
533                 size = pos + ret;
534 
535         /* zero the unwritten part in the partially written block */
536         if (rw == READ && pos < ei->valid_size && ei->valid_size < size) {
537                 iov_iter_revert(iter, size - ei->valid_size);
538                 iov_iter_zero(size - ei->valid_size, iter);
539         }
540 
541         return ret;
542 }
543 
544 static sector_t exfat_aop_bmap(struct address_space *mapping, sector_t block)
545 {
546         sector_t blocknr;
547 
548         /* exfat_get_cluster() assumes the requested blocknr isn't truncated. */
549         down_read(&EXFAT_I(mapping->host)->truncate_lock);
550         blocknr = generic_block_bmap(mapping, block, exfat_get_block);
551         up_read(&EXFAT_I(mapping->host)->truncate_lock);
552         return blocknr;
553 }
554 
555 /*
556  * exfat_block_truncate_page() zeroes out a mapping from file offset `from'
557  * up to the end of the block which corresponds to `from'.
558  * This is required during truncate to physically zeroout the tail end
559  * of that block so it doesn't yield old data if the file is later grown.
560  * Also, avoid causing failure from fsx for cases of "data past EOF"
561  */
562 int exfat_block_truncate_page(struct inode *inode, loff_t from)
563 {
564         return block_truncate_page(inode->i_mapping, from, exfat_get_block);
565 }
566 
567 static const struct address_space_operations exfat_aops = {
568         .dirty_folio    = block_dirty_folio,
569         .invalidate_folio = block_invalidate_folio,
570         .read_folio     = exfat_read_folio,
571         .readahead      = exfat_readahead,
572         .writepages     = exfat_writepages,
573         .write_begin    = exfat_write_begin,
574         .write_end      = exfat_write_end,
575         .direct_IO      = exfat_direct_IO,
576         .bmap           = exfat_aop_bmap,
577         .migrate_folio  = buffer_migrate_folio,
578 };
579 
580 static inline unsigned long exfat_hash(loff_t i_pos)
581 {
582         return hash_32(i_pos, EXFAT_HASH_BITS);
583 }
584 
585 void exfat_hash_inode(struct inode *inode, loff_t i_pos)
586 {
587         struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
588         struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
589 
590         spin_lock(&sbi->inode_hash_lock);
591         EXFAT_I(inode)->i_pos = i_pos;
592         hlist_add_head(&EXFAT_I(inode)->i_hash_fat, head);
593         spin_unlock(&sbi->inode_hash_lock);
594 }
595 
596 void exfat_unhash_inode(struct inode *inode)
597 {
598         struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
599 
600         spin_lock(&sbi->inode_hash_lock);
601         hlist_del_init(&EXFAT_I(inode)->i_hash_fat);
602         EXFAT_I(inode)->i_pos = 0;
603         spin_unlock(&sbi->inode_hash_lock);
604 }
605 
606 struct inode *exfat_iget(struct super_block *sb, loff_t i_pos)
607 {
608         struct exfat_sb_info *sbi = EXFAT_SB(sb);
609         struct exfat_inode_info *info;
610         struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
611         struct inode *inode = NULL;
612 
613         spin_lock(&sbi->inode_hash_lock);
614         hlist_for_each_entry(info, head, i_hash_fat) {
615                 WARN_ON(info->vfs_inode.i_sb != sb);
616 
617                 if (i_pos != info->i_pos)
618                         continue;
619                 inode = igrab(&info->vfs_inode);
620                 if (inode)
621                         break;
622         }
623         spin_unlock(&sbi->inode_hash_lock);
624         return inode;
625 }
626 
627 /* doesn't deal with root inode */
628 static int exfat_fill_inode(struct inode *inode, struct exfat_dir_entry *info)
629 {
630         struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
631         struct exfat_inode_info *ei = EXFAT_I(inode);
632         loff_t size = info->size;
633 
634         ei->dir = info->dir;
635         ei->entry = info->entry;
636         ei->attr = info->attr;
637         ei->start_clu = info->start_clu;
638         ei->flags = info->flags;
639         ei->type = info->type;
640         ei->valid_size = info->valid_size;
641 
642         ei->version = 0;
643         ei->hint_stat.eidx = 0;
644         ei->hint_stat.clu = info->start_clu;
645         ei->hint_femp.eidx = EXFAT_HINT_NONE;
646         ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
647         ei->i_pos = 0;
648 
649         inode->i_uid = sbi->options.fs_uid;
650         inode->i_gid = sbi->options.fs_gid;
651         inode_inc_iversion(inode);
652         inode->i_generation = get_random_u32();
653 
654         if (info->attr & EXFAT_ATTR_SUBDIR) { /* directory */
655                 inode->i_generation &= ~1;
656                 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
657                 inode->i_op = &exfat_dir_inode_operations;
658                 inode->i_fop = &exfat_dir_operations;
659                 set_nlink(inode, info->num_subdirs);
660         } else { /* regular file */
661                 inode->i_generation |= 1;
662                 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
663                 inode->i_op = &exfat_file_inode_operations;
664                 inode->i_fop = &exfat_file_operations;
665                 inode->i_mapping->a_ops = &exfat_aops;
666                 inode->i_mapping->nrpages = 0;
667         }
668 
669         i_size_write(inode, size);
670 
671         /* ondisk and aligned size should be aligned with block size */
672         if (size & (inode->i_sb->s_blocksize - 1)) {
673                 size |= (inode->i_sb->s_blocksize - 1);
674                 size++;
675         }
676 
677         ei->i_size_aligned = size;
678         ei->i_size_ondisk = size;
679 
680         exfat_save_attr(inode, info->attr);
681 
682         inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >> 9;
683         inode_set_mtime_to_ts(inode, info->mtime);
684         inode_set_ctime_to_ts(inode, info->mtime);
685         ei->i_crtime = info->crtime;
686         inode_set_atime_to_ts(inode, info->atime);
687 
688         return 0;
689 }
690 
691 struct inode *exfat_build_inode(struct super_block *sb,
692                 struct exfat_dir_entry *info, loff_t i_pos)
693 {
694         struct inode *inode;
695         int err;
696 
697         inode = exfat_iget(sb, i_pos);
698         if (inode)
699                 goto out;
700         inode = new_inode(sb);
701         if (!inode) {
702                 inode = ERR_PTR(-ENOMEM);
703                 goto out;
704         }
705         inode->i_ino = iunique(sb, EXFAT_ROOT_INO);
706         inode_set_iversion(inode, 1);
707         err = exfat_fill_inode(inode, info);
708         if (err) {
709                 iput(inode);
710                 inode = ERR_PTR(err);
711                 goto out;
712         }
713         exfat_hash_inode(inode, i_pos);
714         insert_inode_hash(inode);
715 out:
716         return inode;
717 }
718 
719 void exfat_evict_inode(struct inode *inode)
720 {
721         truncate_inode_pages(&inode->i_data, 0);
722 
723         if (!inode->i_nlink) {
724                 i_size_write(inode, 0);
725                 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
726                 __exfat_truncate(inode);
727                 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
728         }
729 
730         invalidate_inode_buffers(inode);
731         clear_inode(inode);
732         exfat_cache_inval_inode(inode);
733         exfat_unhash_inode(inode);
734 }
735 

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