1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
6 #include <linux/init.h>
7 #include <linux/buffer_head.h>
8 #include <linux/mpage.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>
17 #include "exfat_raw.h"
20 int __exfat_write_inode(struct inode *inode, int sync)
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;
30 if (inode->i_ino == EXFAT_ROOT_INO)
34 * If the inode is already unlinked, there is no need for updating it.
36 if (ei->dir.dir == DIR_DELETED)
39 if (is_dir && ei->dir.dir == sbi->root_dir && ei->entry == -1)
42 exfat_set_volume_dirty(sb);
44 /* get the directory entry of given file or directory */
45 if (exfat_get_dentry_set(&es, sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES))
47 ep = exfat_get_dentry_cached(&es, ES_IDX_FILE);
48 ep2 = exfat_get_dentry_cached(&es, ES_IDX_STREAM);
50 ep->dentry.file.attr = cpu_to_le16(exfat_make_attr(inode));
52 /* set FILE_INFO structure using the acquired struct exfat_dentry */
53 exfat_set_entry_time(sbi, &ei->i_crtime,
54 &ep->dentry.file.create_tz,
55 &ep->dentry.file.create_time,
56 &ep->dentry.file.create_date,
57 &ep->dentry.file.create_time_cs);
58 exfat_set_entry_time(sbi, &inode->i_mtime,
59 &ep->dentry.file.modify_tz,
60 &ep->dentry.file.modify_time,
61 &ep->dentry.file.modify_date,
62 &ep->dentry.file.modify_time_cs);
63 exfat_set_entry_time(sbi, &inode->i_atime,
64 &ep->dentry.file.access_tz,
65 &ep->dentry.file.access_time,
66 &ep->dentry.file.access_date,
69 /* File size should be zero if there is no cluster allocated */
70 on_disk_size = i_size_read(inode);
72 if (ei->start_clu == EXFAT_EOF_CLUSTER)
75 ep2->dentry.stream.valid_size = cpu_to_le64(on_disk_size);
76 ep2->dentry.stream.size = ep2->dentry.stream.valid_size;
78 ep2->dentry.stream.flags = ei->flags;
79 ep2->dentry.stream.start_clu = cpu_to_le32(ei->start_clu);
81 ep2->dentry.stream.flags = ALLOC_FAT_CHAIN;
82 ep2->dentry.stream.start_clu = EXFAT_FREE_CLUSTER;
85 exfat_update_dir_chksum_with_entry_set(&es);
86 return exfat_put_dentry_set(&es, sync);
89 int exfat_write_inode(struct inode *inode, struct writeback_control *wbc)
93 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
94 ret = __exfat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
95 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
100 void exfat_sync_inode(struct inode *inode)
102 lockdep_assert_held(&EXFAT_SB(inode->i_sb)->s_lock);
103 __exfat_write_inode(inode, 1);
107 * Input: inode, (logical) clu_offset, target allocation area
108 * Output: errcode, cluster number
109 * *clu = (~0), if it's unable to allocate a new cluster
111 static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset,
112 unsigned int *clu, int create)
115 unsigned int last_clu;
116 struct exfat_chain new_clu;
117 struct super_block *sb = inode->i_sb;
118 struct exfat_sb_info *sbi = EXFAT_SB(sb);
119 struct exfat_inode_info *ei = EXFAT_I(inode);
120 unsigned int local_clu_offset = clu_offset;
121 unsigned int num_to_be_allocated = 0, num_clusters = 0;
123 if (ei->i_size_ondisk > 0)
125 EXFAT_B_TO_CLU_ROUND_UP(ei->i_size_ondisk, sbi);
127 if (clu_offset >= num_clusters)
128 num_to_be_allocated = clu_offset - num_clusters + 1;
130 if (!create && (num_to_be_allocated > 0)) {
131 *clu = EXFAT_EOF_CLUSTER;
135 *clu = last_clu = ei->start_clu;
137 if (ei->flags == ALLOC_NO_FAT_CHAIN) {
138 if (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
139 last_clu += clu_offset - 1;
141 if (clu_offset == num_clusters)
142 *clu = EXFAT_EOF_CLUSTER;
146 } else if (ei->type == TYPE_FILE) {
147 unsigned int fclus = 0;
148 int err = exfat_get_cluster(inode, clu_offset,
149 &fclus, clu, &last_clu, 1);
155 /* hint information */
156 if (clu_offset > 0 && ei->hint_bmap.off != EXFAT_EOF_CLUSTER &&
157 ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) {
158 clu_offset -= ei->hint_bmap.off;
159 /* hint_bmap.clu should be valid */
160 WARN_ON(ei->hint_bmap.clu < 2);
161 *clu = ei->hint_bmap.clu;
164 while (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
166 if (exfat_get_next_cluster(sb, clu))
172 if (*clu == EXFAT_EOF_CLUSTER) {
173 exfat_set_volume_dirty(sb);
175 new_clu.dir = (last_clu == EXFAT_EOF_CLUSTER) ?
176 EXFAT_EOF_CLUSTER : last_clu + 1;
178 new_clu.flags = ei->flags;
180 /* allocate a cluster */
181 if (num_to_be_allocated < 1) {
182 /* Broken FAT (i_sze > allocated FAT) */
183 exfat_fs_error(sb, "broken FAT chain.");
187 ret = exfat_alloc_cluster(inode, num_to_be_allocated, &new_clu,
188 inode_needs_sync(inode));
192 if (new_clu.dir == EXFAT_EOF_CLUSTER ||
193 new_clu.dir == EXFAT_FREE_CLUSTER) {
195 "bogus cluster new allocated (last_clu : %u, new_clu : %u)",
196 last_clu, new_clu.dir);
200 /* append to the FAT chain */
201 if (last_clu == EXFAT_EOF_CLUSTER) {
202 if (new_clu.flags == ALLOC_FAT_CHAIN)
203 ei->flags = ALLOC_FAT_CHAIN;
204 ei->start_clu = new_clu.dir;
206 if (new_clu.flags != ei->flags) {
207 /* no-fat-chain bit is disabled,
208 * so fat-chain should be synced with
211 exfat_chain_cont_cluster(sb, ei->start_clu,
213 ei->flags = ALLOC_FAT_CHAIN;
215 if (new_clu.flags == ALLOC_FAT_CHAIN)
216 if (exfat_ent_set(sb, last_clu, new_clu.dir))
220 num_clusters += num_to_be_allocated;
223 inode->i_blocks += EXFAT_CLU_TO_B(num_to_be_allocated, sbi) >> 9;
226 * Move *clu pointer along FAT chains (hole care) because the
227 * caller of this function expect *clu to be the last cluster.
228 * This only works when num_to_be_allocated >= 2,
229 * *clu = (the first cluster of the allocated chain) =>
230 * (the last cluster of ...)
232 if (ei->flags == ALLOC_NO_FAT_CHAIN) {
233 *clu += num_to_be_allocated - 1;
235 while (num_to_be_allocated > 1) {
236 if (exfat_get_next_cluster(sb, clu))
238 num_to_be_allocated--;
244 /* hint information */
245 ei->hint_bmap.off = local_clu_offset;
246 ei->hint_bmap.clu = *clu;
251 static int exfat_map_new_buffer(struct exfat_inode_info *ei,
252 struct buffer_head *bh, loff_t pos)
254 if (buffer_delay(bh) && pos > ei->i_size_aligned)
259 * Adjust i_size_aligned if i_size_ondisk is bigger than it.
261 if (ei->i_size_ondisk > ei->i_size_aligned)
262 ei->i_size_aligned = ei->i_size_ondisk;
266 static int exfat_get_block(struct inode *inode, sector_t iblock,
267 struct buffer_head *bh_result, int create)
269 struct exfat_inode_info *ei = EXFAT_I(inode);
270 struct super_block *sb = inode->i_sb;
271 struct exfat_sb_info *sbi = EXFAT_SB(sb);
272 unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
274 unsigned long mapped_blocks = 0;
275 unsigned int cluster, sec_offset;
280 mutex_lock(&sbi->s_lock);
281 last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb);
282 if (iblock >= last_block && !create)
285 /* Is this block already allocated? */
286 err = exfat_map_cluster(inode, iblock >> sbi->sect_per_clus_bits,
290 exfat_fs_error_ratelimit(sb,
291 "failed to bmap (inode : %p iblock : %llu, err : %d)",
292 inode, (unsigned long long)iblock, err);
296 if (cluster == EXFAT_EOF_CLUSTER)
299 /* sector offset in cluster */
300 sec_offset = iblock & (sbi->sect_per_clus - 1);
302 phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset;
303 mapped_blocks = sbi->sect_per_clus - sec_offset;
304 max_blocks = min(mapped_blocks, max_blocks);
306 /* Treat newly added block / cluster */
307 if (iblock < last_block)
310 if (create || buffer_delay(bh_result)) {
311 pos = EXFAT_BLK_TO_B((iblock + 1), sb);
312 if (ei->i_size_ondisk < pos)
313 ei->i_size_ondisk = pos;
317 err = exfat_map_new_buffer(ei, bh_result, pos);
320 "requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n",
321 pos, ei->i_size_aligned);
326 if (buffer_delay(bh_result))
327 clear_buffer_delay(bh_result);
328 map_bh(bh_result, sb, phys);
330 bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb);
332 mutex_unlock(&sbi->s_lock);
336 static int exfat_read_folio(struct file *file, struct folio *folio)
338 return mpage_read_folio(folio, exfat_get_block);
341 static void exfat_readahead(struct readahead_control *rac)
343 mpage_readahead(rac, exfat_get_block);
346 static int exfat_writepages(struct address_space *mapping,
347 struct writeback_control *wbc)
349 return mpage_writepages(mapping, wbc, exfat_get_block);
352 static void exfat_write_failed(struct address_space *mapping, loff_t to)
354 struct inode *inode = mapping->host;
356 if (to > i_size_read(inode)) {
357 truncate_pagecache(inode, i_size_read(inode));
358 inode->i_mtime = inode_set_ctime_current(inode);
359 exfat_truncate(inode);
363 static int exfat_write_begin(struct file *file, struct address_space *mapping,
364 loff_t pos, unsigned int len,
365 struct page **pagep, void **fsdata)
370 ret = cont_write_begin(file, mapping, pos, len, pagep, fsdata,
372 &EXFAT_I(mapping->host)->i_size_ondisk);
375 exfat_write_failed(mapping, pos+len);
380 static int exfat_write_end(struct file *file, struct address_space *mapping,
381 loff_t pos, unsigned int len, unsigned int copied,
382 struct page *pagep, void *fsdata)
384 struct inode *inode = mapping->host;
385 struct exfat_inode_info *ei = EXFAT_I(inode);
388 err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
390 if (ei->i_size_aligned < i_size_read(inode)) {
391 exfat_fs_error(inode->i_sb,
392 "invalid size(size(%llu) > aligned(%llu)\n",
393 i_size_read(inode), ei->i_size_aligned);
398 exfat_write_failed(mapping, pos+len);
400 if (!(err < 0) && !(ei->attr & ATTR_ARCHIVE)) {
401 inode->i_mtime = inode_set_ctime_current(inode);
402 ei->attr |= ATTR_ARCHIVE;
403 mark_inode_dirty(inode);
409 static ssize_t exfat_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
411 struct address_space *mapping = iocb->ki_filp->f_mapping;
412 struct inode *inode = mapping->host;
413 loff_t size = iocb->ki_pos + iov_iter_count(iter);
414 int rw = iov_iter_rw(iter);
419 * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
420 * so we need to update the ->i_size_aligned to block boundary.
422 * But we must fill the remaining area or hole by nul for
423 * updating ->i_size_aligned
425 * Return 0, and fallback to normal buffered write.
427 if (EXFAT_I(inode)->i_size_aligned < size)
432 * Need to use the DIO_LOCKING for avoiding the race
433 * condition of exfat_get_block() and ->truncate().
435 ret = blockdev_direct_IO(iocb, inode, iter, exfat_get_block);
436 if (ret < 0 && (rw & WRITE))
437 exfat_write_failed(mapping, size);
441 static sector_t exfat_aop_bmap(struct address_space *mapping, sector_t block)
445 /* exfat_get_cluster() assumes the requested blocknr isn't truncated. */
446 down_read(&EXFAT_I(mapping->host)->truncate_lock);
447 blocknr = generic_block_bmap(mapping, block, exfat_get_block);
448 up_read(&EXFAT_I(mapping->host)->truncate_lock);
453 * exfat_block_truncate_page() zeroes out a mapping from file offset `from'
454 * up to the end of the block which corresponds to `from'.
455 * This is required during truncate to physically zeroout the tail end
456 * of that block so it doesn't yield old data if the file is later grown.
457 * Also, avoid causing failure from fsx for cases of "data past EOF"
459 int exfat_block_truncate_page(struct inode *inode, loff_t from)
461 return block_truncate_page(inode->i_mapping, from, exfat_get_block);
464 static const struct address_space_operations exfat_aops = {
465 .dirty_folio = block_dirty_folio,
466 .invalidate_folio = block_invalidate_folio,
467 .read_folio = exfat_read_folio,
468 .readahead = exfat_readahead,
469 .writepages = exfat_writepages,
470 .write_begin = exfat_write_begin,
471 .write_end = exfat_write_end,
472 .direct_IO = exfat_direct_IO,
473 .bmap = exfat_aop_bmap,
474 .migrate_folio = buffer_migrate_folio,
477 static inline unsigned long exfat_hash(loff_t i_pos)
479 return hash_32(i_pos, EXFAT_HASH_BITS);
482 void exfat_hash_inode(struct inode *inode, loff_t i_pos)
484 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
485 struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
487 spin_lock(&sbi->inode_hash_lock);
488 EXFAT_I(inode)->i_pos = i_pos;
489 hlist_add_head(&EXFAT_I(inode)->i_hash_fat, head);
490 spin_unlock(&sbi->inode_hash_lock);
493 void exfat_unhash_inode(struct inode *inode)
495 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
497 spin_lock(&sbi->inode_hash_lock);
498 hlist_del_init(&EXFAT_I(inode)->i_hash_fat);
499 EXFAT_I(inode)->i_pos = 0;
500 spin_unlock(&sbi->inode_hash_lock);
503 struct inode *exfat_iget(struct super_block *sb, loff_t i_pos)
505 struct exfat_sb_info *sbi = EXFAT_SB(sb);
506 struct exfat_inode_info *info;
507 struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
508 struct inode *inode = NULL;
510 spin_lock(&sbi->inode_hash_lock);
511 hlist_for_each_entry(info, head, i_hash_fat) {
512 WARN_ON(info->vfs_inode.i_sb != sb);
514 if (i_pos != info->i_pos)
516 inode = igrab(&info->vfs_inode);
520 spin_unlock(&sbi->inode_hash_lock);
524 /* doesn't deal with root inode */
525 static int exfat_fill_inode(struct inode *inode, struct exfat_dir_entry *info)
527 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
528 struct exfat_inode_info *ei = EXFAT_I(inode);
529 loff_t size = info->size;
532 ei->entry = info->entry;
533 ei->attr = info->attr;
534 ei->start_clu = info->start_clu;
535 ei->flags = info->flags;
536 ei->type = info->type;
539 ei->hint_stat.eidx = 0;
540 ei->hint_stat.clu = info->start_clu;
541 ei->hint_femp.eidx = EXFAT_HINT_NONE;
542 ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
545 inode->i_uid = sbi->options.fs_uid;
546 inode->i_gid = sbi->options.fs_gid;
547 inode_inc_iversion(inode);
548 inode->i_generation = get_random_u32();
550 if (info->attr & ATTR_SUBDIR) { /* directory */
551 inode->i_generation &= ~1;
552 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
553 inode->i_op = &exfat_dir_inode_operations;
554 inode->i_fop = &exfat_dir_operations;
555 set_nlink(inode, info->num_subdirs);
556 } else { /* regular file */
557 inode->i_generation |= 1;
558 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
559 inode->i_op = &exfat_file_inode_operations;
560 inode->i_fop = &exfat_file_operations;
561 inode->i_mapping->a_ops = &exfat_aops;
562 inode->i_mapping->nrpages = 0;
565 i_size_write(inode, size);
567 /* ondisk and aligned size should be aligned with block size */
568 if (size & (inode->i_sb->s_blocksize - 1)) {
569 size |= (inode->i_sb->s_blocksize - 1);
573 ei->i_size_aligned = size;
574 ei->i_size_ondisk = size;
576 exfat_save_attr(inode, info->attr);
578 inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >> 9;
579 inode->i_mtime = info->mtime;
580 inode_set_ctime_to_ts(inode, info->mtime);
581 ei->i_crtime = info->crtime;
582 inode->i_atime = info->atime;
587 struct inode *exfat_build_inode(struct super_block *sb,
588 struct exfat_dir_entry *info, loff_t i_pos)
593 inode = exfat_iget(sb, i_pos);
596 inode = new_inode(sb);
598 inode = ERR_PTR(-ENOMEM);
601 inode->i_ino = iunique(sb, EXFAT_ROOT_INO);
602 inode_set_iversion(inode, 1);
603 err = exfat_fill_inode(inode, info);
606 inode = ERR_PTR(err);
609 exfat_hash_inode(inode, i_pos);
610 insert_inode_hash(inode);
615 void exfat_evict_inode(struct inode *inode)
617 truncate_inode_pages(&inode->i_data, 0);
619 if (!inode->i_nlink) {
620 i_size_write(inode, 0);
621 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
622 __exfat_truncate(inode);
623 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
626 invalidate_inode_buffers(inode);
628 exfat_cache_inval_inode(inode);
629 exfat_unhash_inode(inode);