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 static 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 = 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;
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 es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES);
48 ep = exfat_get_dentry_cached(es, 0);
49 ep2 = exfat_get_dentry_cached(es, 1);
51 ep->dentry.file.attr = cpu_to_le16(exfat_make_attr(inode));
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,
70 /* File size should be zero if there is no cluster allocated */
71 on_disk_size = i_size_read(inode);
73 if (ei->start_clu == EXFAT_EOF_CLUSTER)
76 ep2->dentry.stream.valid_size = cpu_to_le64(on_disk_size);
77 ep2->dentry.stream.size = ep2->dentry.stream.valid_size;
79 exfat_update_dir_chksum_with_entry_set(es);
80 return exfat_free_dentry_set(es, sync);
83 int exfat_write_inode(struct inode *inode, struct writeback_control *wbc)
87 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
88 ret = __exfat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
89 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
94 void exfat_sync_inode(struct inode *inode)
96 lockdep_assert_held(&EXFAT_SB(inode->i_sb)->s_lock);
97 __exfat_write_inode(inode, 1);
101 * Input: inode, (logical) clu_offset, target allocation area
102 * Output: errcode, cluster number
103 * *clu = (~0), if it's unable to allocate a new cluster
105 static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset,
106 unsigned int *clu, int create)
108 int ret, modified = false;
109 unsigned int last_clu;
110 struct exfat_chain new_clu;
111 struct super_block *sb = inode->i_sb;
112 struct exfat_sb_info *sbi = EXFAT_SB(sb);
113 struct exfat_inode_info *ei = EXFAT_I(inode);
114 unsigned int local_clu_offset = clu_offset;
115 unsigned int num_to_be_allocated = 0, num_clusters = 0;
117 if (ei->i_size_ondisk > 0)
119 EXFAT_B_TO_CLU_ROUND_UP(ei->i_size_ondisk, sbi);
121 if (clu_offset >= num_clusters)
122 num_to_be_allocated = clu_offset - num_clusters + 1;
124 if (!create && (num_to_be_allocated > 0)) {
125 *clu = EXFAT_EOF_CLUSTER;
129 *clu = last_clu = ei->start_clu;
131 if (ei->flags == ALLOC_NO_FAT_CHAIN) {
132 if (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
133 last_clu += clu_offset - 1;
135 if (clu_offset == num_clusters)
136 *clu = EXFAT_EOF_CLUSTER;
140 } else if (ei->type == TYPE_FILE) {
141 unsigned int fclus = 0;
142 int err = exfat_get_cluster(inode, clu_offset,
143 &fclus, clu, &last_clu, 1);
149 /* hint information */
150 if (clu_offset > 0 && ei->hint_bmap.off != EXFAT_EOF_CLUSTER &&
151 ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) {
152 clu_offset -= ei->hint_bmap.off;
153 /* hint_bmap.clu should be valid */
154 WARN_ON(ei->hint_bmap.clu < 2);
155 *clu = ei->hint_bmap.clu;
158 while (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
160 if (exfat_get_next_cluster(sb, clu))
166 if (*clu == EXFAT_EOF_CLUSTER) {
167 exfat_set_volume_dirty(sb);
169 new_clu.dir = (last_clu == EXFAT_EOF_CLUSTER) ?
170 EXFAT_EOF_CLUSTER : last_clu + 1;
172 new_clu.flags = ei->flags;
174 /* allocate a cluster */
175 if (num_to_be_allocated < 1) {
176 /* Broken FAT (i_sze > allocated FAT) */
177 exfat_fs_error(sb, "broken FAT chain.");
181 ret = exfat_alloc_cluster(inode, num_to_be_allocated, &new_clu,
182 inode_needs_sync(inode));
186 if (new_clu.dir == EXFAT_EOF_CLUSTER ||
187 new_clu.dir == EXFAT_FREE_CLUSTER) {
189 "bogus cluster new allocated (last_clu : %u, new_clu : %u)",
190 last_clu, new_clu.dir);
194 /* append to the FAT chain */
195 if (last_clu == EXFAT_EOF_CLUSTER) {
196 if (new_clu.flags == ALLOC_FAT_CHAIN)
197 ei->flags = ALLOC_FAT_CHAIN;
198 ei->start_clu = new_clu.dir;
201 if (new_clu.flags != ei->flags) {
202 /* no-fat-chain bit is disabled,
203 * so fat-chain should be synced with
206 exfat_chain_cont_cluster(sb, ei->start_clu,
208 ei->flags = ALLOC_FAT_CHAIN;
211 if (new_clu.flags == ALLOC_FAT_CHAIN)
212 if (exfat_ent_set(sb, last_clu, new_clu.dir))
216 num_clusters += num_to_be_allocated;
219 if (ei->dir.dir != DIR_DELETED && modified) {
220 struct exfat_dentry *ep;
221 struct exfat_entry_set_cache *es;
224 es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry,
228 /* get stream entry */
229 ep = exfat_get_dentry_cached(es, 1);
231 /* update directory entry */
232 ep->dentry.stream.flags = ei->flags;
233 ep->dentry.stream.start_clu =
234 cpu_to_le32(ei->start_clu);
235 ep->dentry.stream.valid_size =
236 cpu_to_le64(i_size_read(inode));
237 ep->dentry.stream.size =
238 ep->dentry.stream.valid_size;
240 exfat_update_dir_chksum_with_entry_set(es);
241 err = exfat_free_dentry_set(es, inode_needs_sync(inode));
244 } /* end of if != DIR_DELETED */
247 num_to_be_allocated << sbi->sect_per_clus_bits;
250 * Move *clu pointer along FAT chains (hole care) because the
251 * caller of this function expect *clu to be the last cluster.
252 * This only works when num_to_be_allocated >= 2,
253 * *clu = (the first cluster of the allocated chain) =>
254 * (the last cluster of ...)
256 if (ei->flags == ALLOC_NO_FAT_CHAIN) {
257 *clu += num_to_be_allocated - 1;
259 while (num_to_be_allocated > 1) {
260 if (exfat_get_next_cluster(sb, clu))
262 num_to_be_allocated--;
268 /* hint information */
269 ei->hint_bmap.off = local_clu_offset;
270 ei->hint_bmap.clu = *clu;
275 static int exfat_map_new_buffer(struct exfat_inode_info *ei,
276 struct buffer_head *bh, loff_t pos)
278 if (buffer_delay(bh) && pos > ei->i_size_aligned)
283 * Adjust i_size_aligned if i_size_ondisk is bigger than it.
285 if (ei->i_size_ondisk > ei->i_size_aligned)
286 ei->i_size_aligned = ei->i_size_ondisk;
290 static int exfat_get_block(struct inode *inode, sector_t iblock,
291 struct buffer_head *bh_result, int create)
293 struct exfat_inode_info *ei = EXFAT_I(inode);
294 struct super_block *sb = inode->i_sb;
295 struct exfat_sb_info *sbi = EXFAT_SB(sb);
296 unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
298 unsigned long mapped_blocks = 0;
299 unsigned int cluster, sec_offset;
304 mutex_lock(&sbi->s_lock);
305 last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb);
306 if (iblock >= last_block && !create)
309 /* Is this block already allocated? */
310 err = exfat_map_cluster(inode, iblock >> sbi->sect_per_clus_bits,
314 exfat_fs_error_ratelimit(sb,
315 "failed to bmap (inode : %p iblock : %llu, err : %d)",
316 inode, (unsigned long long)iblock, err);
320 if (cluster == EXFAT_EOF_CLUSTER)
323 /* sector offset in cluster */
324 sec_offset = iblock & (sbi->sect_per_clus - 1);
326 phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset;
327 mapped_blocks = sbi->sect_per_clus - sec_offset;
328 max_blocks = min(mapped_blocks, max_blocks);
330 /* Treat newly added block / cluster */
331 if (iblock < last_block)
334 if (create || buffer_delay(bh_result)) {
335 pos = EXFAT_BLK_TO_B((iblock + 1), sb);
336 if (ei->i_size_ondisk < pos)
337 ei->i_size_ondisk = pos;
341 err = exfat_map_new_buffer(ei, bh_result, pos);
344 "requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n",
345 pos, ei->i_size_aligned);
350 if (buffer_delay(bh_result))
351 clear_buffer_delay(bh_result);
352 map_bh(bh_result, sb, phys);
354 bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb);
356 mutex_unlock(&sbi->s_lock);
360 static int exfat_read_folio(struct file *file, struct folio *folio)
362 return mpage_read_folio(folio, exfat_get_block);
365 static void exfat_readahead(struct readahead_control *rac)
367 mpage_readahead(rac, exfat_get_block);
370 static int exfat_writepage(struct page *page, struct writeback_control *wbc)
372 return block_write_full_page(page, exfat_get_block, wbc);
375 static int exfat_writepages(struct address_space *mapping,
376 struct writeback_control *wbc)
378 return mpage_writepages(mapping, wbc, exfat_get_block);
381 static void exfat_write_failed(struct address_space *mapping, loff_t to)
383 struct inode *inode = mapping->host;
385 if (to > i_size_read(inode)) {
386 truncate_pagecache(inode, i_size_read(inode));
387 exfat_truncate(inode, EXFAT_I(inode)->i_size_aligned);
391 static int exfat_write_begin(struct file *file, struct address_space *mapping,
392 loff_t pos, unsigned int len,
393 struct page **pagep, void **fsdata)
398 ret = cont_write_begin(file, mapping, pos, len, pagep, fsdata,
400 &EXFAT_I(mapping->host)->i_size_ondisk);
403 exfat_write_failed(mapping, pos+len);
408 static int exfat_write_end(struct file *file, struct address_space *mapping,
409 loff_t pos, unsigned int len, unsigned int copied,
410 struct page *pagep, void *fsdata)
412 struct inode *inode = mapping->host;
413 struct exfat_inode_info *ei = EXFAT_I(inode);
416 err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
418 if (ei->i_size_aligned < i_size_read(inode)) {
419 exfat_fs_error(inode->i_sb,
420 "invalid size(size(%llu) > aligned(%llu)\n",
421 i_size_read(inode), ei->i_size_aligned);
426 exfat_write_failed(mapping, pos+len);
428 if (!(err < 0) && !(ei->attr & ATTR_ARCHIVE)) {
429 inode->i_mtime = inode->i_ctime = current_time(inode);
430 ei->attr |= ATTR_ARCHIVE;
431 mark_inode_dirty(inode);
437 static ssize_t exfat_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
439 struct address_space *mapping = iocb->ki_filp->f_mapping;
440 struct inode *inode = mapping->host;
441 loff_t size = iocb->ki_pos + iov_iter_count(iter);
442 int rw = iov_iter_rw(iter);
447 * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
448 * so we need to update the ->i_size_aligned to block boundary.
450 * But we must fill the remaining area or hole by nul for
451 * updating ->i_size_aligned
453 * Return 0, and fallback to normal buffered write.
455 if (EXFAT_I(inode)->i_size_aligned < size)
460 * Need to use the DIO_LOCKING for avoiding the race
461 * condition of exfat_get_block() and ->truncate().
463 ret = blockdev_direct_IO(iocb, inode, iter, exfat_get_block);
464 if (ret < 0 && (rw & WRITE))
465 exfat_write_failed(mapping, size);
469 static sector_t exfat_aop_bmap(struct address_space *mapping, sector_t block)
473 /* exfat_get_cluster() assumes the requested blocknr isn't truncated. */
474 down_read(&EXFAT_I(mapping->host)->truncate_lock);
475 blocknr = generic_block_bmap(mapping, block, exfat_get_block);
476 up_read(&EXFAT_I(mapping->host)->truncate_lock);
481 * exfat_block_truncate_page() zeroes out a mapping from file offset `from'
482 * up to the end of the block which corresponds to `from'.
483 * This is required during truncate to physically zeroout the tail end
484 * of that block so it doesn't yield old data if the file is later grown.
485 * Also, avoid causing failure from fsx for cases of "data past EOF"
487 int exfat_block_truncate_page(struct inode *inode, loff_t from)
489 return block_truncate_page(inode->i_mapping, from, exfat_get_block);
492 static const struct address_space_operations exfat_aops = {
493 .dirty_folio = block_dirty_folio,
494 .invalidate_folio = block_invalidate_folio,
495 .read_folio = exfat_read_folio,
496 .readahead = exfat_readahead,
497 .writepage = exfat_writepage,
498 .writepages = exfat_writepages,
499 .write_begin = exfat_write_begin,
500 .write_end = exfat_write_end,
501 .direct_IO = exfat_direct_IO,
502 .bmap = exfat_aop_bmap
505 static inline unsigned long exfat_hash(loff_t i_pos)
507 return hash_32(i_pos, EXFAT_HASH_BITS);
510 void exfat_hash_inode(struct inode *inode, loff_t i_pos)
512 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
513 struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
515 spin_lock(&sbi->inode_hash_lock);
516 EXFAT_I(inode)->i_pos = i_pos;
517 hlist_add_head(&EXFAT_I(inode)->i_hash_fat, head);
518 spin_unlock(&sbi->inode_hash_lock);
521 void exfat_unhash_inode(struct inode *inode)
523 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
525 spin_lock(&sbi->inode_hash_lock);
526 hlist_del_init(&EXFAT_I(inode)->i_hash_fat);
527 EXFAT_I(inode)->i_pos = 0;
528 spin_unlock(&sbi->inode_hash_lock);
531 struct inode *exfat_iget(struct super_block *sb, loff_t i_pos)
533 struct exfat_sb_info *sbi = EXFAT_SB(sb);
534 struct exfat_inode_info *info;
535 struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
536 struct inode *inode = NULL;
538 spin_lock(&sbi->inode_hash_lock);
539 hlist_for_each_entry(info, head, i_hash_fat) {
540 WARN_ON(info->vfs_inode.i_sb != sb);
542 if (i_pos != info->i_pos)
544 inode = igrab(&info->vfs_inode);
548 spin_unlock(&sbi->inode_hash_lock);
552 /* doesn't deal with root inode */
553 static int exfat_fill_inode(struct inode *inode, struct exfat_dir_entry *info)
555 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
556 struct exfat_inode_info *ei = EXFAT_I(inode);
557 loff_t size = info->size;
560 ei->entry = info->entry;
561 ei->attr = info->attr;
562 ei->start_clu = info->start_clu;
563 ei->flags = info->flags;
564 ei->type = info->type;
567 ei->hint_stat.eidx = 0;
568 ei->hint_stat.clu = info->start_clu;
569 ei->hint_femp.eidx = EXFAT_HINT_NONE;
570 ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
573 inode->i_uid = sbi->options.fs_uid;
574 inode->i_gid = sbi->options.fs_gid;
575 inode_inc_iversion(inode);
576 inode->i_generation = prandom_u32();
578 if (info->attr & ATTR_SUBDIR) { /* directory */
579 inode->i_generation &= ~1;
580 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
581 inode->i_op = &exfat_dir_inode_operations;
582 inode->i_fop = &exfat_dir_operations;
583 set_nlink(inode, info->num_subdirs);
584 } else { /* regular file */
585 inode->i_generation |= 1;
586 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
587 inode->i_op = &exfat_file_inode_operations;
588 inode->i_fop = &exfat_file_operations;
589 inode->i_mapping->a_ops = &exfat_aops;
590 inode->i_mapping->nrpages = 0;
593 i_size_write(inode, size);
595 /* ondisk and aligned size should be aligned with block size */
596 if (size & (inode->i_sb->s_blocksize - 1)) {
597 size |= (inode->i_sb->s_blocksize - 1);
601 ei->i_size_aligned = size;
602 ei->i_size_ondisk = size;
604 exfat_save_attr(inode, info->attr);
606 inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >>
608 inode->i_mtime = info->mtime;
609 inode->i_ctime = info->mtime;
610 ei->i_crtime = info->crtime;
611 inode->i_atime = info->atime;
616 struct inode *exfat_build_inode(struct super_block *sb,
617 struct exfat_dir_entry *info, loff_t i_pos)
622 inode = exfat_iget(sb, i_pos);
625 inode = new_inode(sb);
627 inode = ERR_PTR(-ENOMEM);
630 inode->i_ino = iunique(sb, EXFAT_ROOT_INO);
631 inode_set_iversion(inode, 1);
632 err = exfat_fill_inode(inode, info);
635 inode = ERR_PTR(err);
638 exfat_hash_inode(inode, i_pos);
639 insert_inode_hash(inode);
644 void exfat_evict_inode(struct inode *inode)
646 truncate_inode_pages(&inode->i_data, 0);
648 if (!inode->i_nlink) {
649 i_size_write(inode, 0);
650 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
651 __exfat_truncate(inode, 0);
652 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
655 invalidate_inode_buffers(inode);
657 exfat_cache_inval_inode(inode);
658 exfat_unhash_inode(inode);