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 indode 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);
185 if (new_clu.dir == EXFAT_EOF_CLUSTER ||
186 new_clu.dir == EXFAT_FREE_CLUSTER) {
188 "bogus cluster new allocated (last_clu : %u, new_clu : %u)",
189 last_clu, new_clu.dir);
193 /* append to the FAT chain */
194 if (last_clu == EXFAT_EOF_CLUSTER) {
195 if (new_clu.flags == ALLOC_FAT_CHAIN)
196 ei->flags = ALLOC_FAT_CHAIN;
197 ei->start_clu = new_clu.dir;
200 if (new_clu.flags != ei->flags) {
201 /* no-fat-chain bit is disabled,
202 * so fat-chain should be synced with
205 exfat_chain_cont_cluster(sb, ei->start_clu,
207 ei->flags = ALLOC_FAT_CHAIN;
210 if (new_clu.flags == ALLOC_FAT_CHAIN)
211 if (exfat_ent_set(sb, last_clu, new_clu.dir))
215 num_clusters += num_to_be_allocated;
218 if (ei->dir.dir != DIR_DELETED && modified) {
219 struct exfat_dentry *ep;
220 struct exfat_entry_set_cache *es;
223 es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry,
227 /* get stream entry */
228 ep = exfat_get_dentry_cached(es, 1);
230 /* update directory entry */
231 ep->dentry.stream.flags = ei->flags;
232 ep->dentry.stream.start_clu =
233 cpu_to_le32(ei->start_clu);
234 ep->dentry.stream.valid_size =
235 cpu_to_le64(i_size_read(inode));
236 ep->dentry.stream.size =
237 ep->dentry.stream.valid_size;
239 exfat_update_dir_chksum_with_entry_set(es);
240 err = exfat_free_dentry_set(es, inode_needs_sync(inode));
243 } /* end of if != DIR_DELETED */
246 num_to_be_allocated << sbi->sect_per_clus_bits;
249 * Move *clu pointer along FAT chains (hole care) because the
250 * caller of this function expect *clu to be the last cluster.
251 * This only works when num_to_be_allocated >= 2,
252 * *clu = (the first cluster of the allocated chain) =>
253 * (the last cluster of ...)
255 if (ei->flags == ALLOC_NO_FAT_CHAIN) {
256 *clu += num_to_be_allocated - 1;
258 while (num_to_be_allocated > 1) {
259 if (exfat_get_next_cluster(sb, clu))
261 num_to_be_allocated--;
267 /* hint information */
268 ei->hint_bmap.off = local_clu_offset;
269 ei->hint_bmap.clu = *clu;
274 static int exfat_map_new_buffer(struct exfat_inode_info *ei,
275 struct buffer_head *bh, loff_t pos)
277 if (buffer_delay(bh) && pos > ei->i_size_aligned)
282 * Adjust i_size_aligned if i_size_ondisk is bigger than it.
284 if (ei->i_size_ondisk > ei->i_size_aligned)
285 ei->i_size_aligned = ei->i_size_ondisk;
289 static int exfat_get_block(struct inode *inode, sector_t iblock,
290 struct buffer_head *bh_result, int create)
292 struct exfat_inode_info *ei = EXFAT_I(inode);
293 struct super_block *sb = inode->i_sb;
294 struct exfat_sb_info *sbi = EXFAT_SB(sb);
295 unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
297 unsigned long mapped_blocks = 0;
298 unsigned int cluster, sec_offset;
303 mutex_lock(&sbi->s_lock);
304 last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb);
305 if (iblock >= last_block && !create)
308 /* Is this block already allocated? */
309 err = exfat_map_cluster(inode, iblock >> sbi->sect_per_clus_bits,
313 exfat_fs_error_ratelimit(sb,
314 "failed to bmap (inode : %p iblock : %llu, err : %d)",
315 inode, (unsigned long long)iblock, err);
319 if (cluster == EXFAT_EOF_CLUSTER)
322 /* sector offset in cluster */
323 sec_offset = iblock & (sbi->sect_per_clus - 1);
325 phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset;
326 mapped_blocks = sbi->sect_per_clus - sec_offset;
327 max_blocks = min(mapped_blocks, max_blocks);
329 /* Treat newly added block / cluster */
330 if (iblock < last_block)
333 if (create || buffer_delay(bh_result)) {
334 pos = EXFAT_BLK_TO_B((iblock + 1), sb);
335 if (ei->i_size_ondisk < pos)
336 ei->i_size_ondisk = pos;
340 err = exfat_map_new_buffer(ei, bh_result, pos);
343 "requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n",
344 pos, ei->i_size_aligned);
349 if (buffer_delay(bh_result))
350 clear_buffer_delay(bh_result);
351 map_bh(bh_result, sb, phys);
353 bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb);
355 mutex_unlock(&sbi->s_lock);
359 static int exfat_readpage(struct file *file, struct page *page)
361 return mpage_readpage(page, exfat_get_block);
364 static void exfat_readahead(struct readahead_control *rac)
366 mpage_readahead(rac, exfat_get_block);
369 static int exfat_writepage(struct page *page, struct writeback_control *wbc)
371 return block_write_full_page(page, exfat_get_block, wbc);
374 static int exfat_writepages(struct address_space *mapping,
375 struct writeback_control *wbc)
377 return mpage_writepages(mapping, wbc, exfat_get_block);
380 static void exfat_write_failed(struct address_space *mapping, loff_t to)
382 struct inode *inode = mapping->host;
384 if (to > i_size_read(inode)) {
385 truncate_pagecache(inode, i_size_read(inode));
386 exfat_truncate(inode, EXFAT_I(inode)->i_size_aligned);
390 static int exfat_write_begin(struct file *file, struct address_space *mapping,
391 loff_t pos, unsigned int len, unsigned int flags,
392 struct page **pagep, void **fsdata)
397 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
399 &EXFAT_I(mapping->host)->i_size_ondisk);
402 exfat_write_failed(mapping, pos+len);
407 static int exfat_write_end(struct file *file, struct address_space *mapping,
408 loff_t pos, unsigned int len, unsigned int copied,
409 struct page *pagep, void *fsdata)
411 struct inode *inode = mapping->host;
412 struct exfat_inode_info *ei = EXFAT_I(inode);
415 err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
417 if (ei->i_size_aligned < i_size_read(inode)) {
418 exfat_fs_error(inode->i_sb,
419 "invalid size(size(%llu) > aligned(%llu)\n",
420 i_size_read(inode), ei->i_size_aligned);
425 exfat_write_failed(mapping, pos+len);
427 if (!(err < 0) && !(ei->attr & ATTR_ARCHIVE)) {
428 inode->i_mtime = inode->i_ctime = current_time(inode);
429 ei->attr |= ATTR_ARCHIVE;
430 mark_inode_dirty(inode);
436 static ssize_t exfat_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
438 struct address_space *mapping = iocb->ki_filp->f_mapping;
439 struct inode *inode = mapping->host;
440 loff_t size = iocb->ki_pos + iov_iter_count(iter);
441 int rw = iov_iter_rw(iter);
446 * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
447 * so we need to update the ->i_size_aligned to block boundary.
449 * But we must fill the remaining area or hole by nul for
450 * updating ->i_size_aligned
452 * Return 0, and fallback to normal buffered write.
454 if (EXFAT_I(inode)->i_size_aligned < size)
459 * Need to use the DIO_LOCKING for avoiding the race
460 * condition of exfat_get_block() and ->truncate().
462 ret = blockdev_direct_IO(iocb, inode, iter, exfat_get_block);
463 if (ret < 0 && (rw & WRITE))
464 exfat_write_failed(mapping, size);
468 static sector_t exfat_aop_bmap(struct address_space *mapping, sector_t block)
472 /* exfat_get_cluster() assumes the requested blocknr isn't truncated. */
473 down_read(&EXFAT_I(mapping->host)->truncate_lock);
474 blocknr = generic_block_bmap(mapping, block, exfat_get_block);
475 up_read(&EXFAT_I(mapping->host)->truncate_lock);
480 * exfat_block_truncate_page() zeroes out a mapping from file offset `from'
481 * up to the end of the block which corresponds to `from'.
482 * This is required during truncate to physically zeroout the tail end
483 * of that block so it doesn't yield old data if the file is later grown.
484 * Also, avoid causing failure from fsx for cases of "data past EOF"
486 int exfat_block_truncate_page(struct inode *inode, loff_t from)
488 return block_truncate_page(inode->i_mapping, from, exfat_get_block);
491 static const struct address_space_operations exfat_aops = {
492 .readpage = exfat_readpage,
493 .readahead = exfat_readahead,
494 .writepage = exfat_writepage,
495 .writepages = exfat_writepages,
496 .write_begin = exfat_write_begin,
497 .write_end = exfat_write_end,
498 .direct_IO = exfat_direct_IO,
499 .bmap = exfat_aop_bmap
502 static inline unsigned long exfat_hash(loff_t i_pos)
504 return hash_32(i_pos, EXFAT_HASH_BITS);
507 void exfat_hash_inode(struct inode *inode, loff_t i_pos)
509 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
510 struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
512 spin_lock(&sbi->inode_hash_lock);
513 EXFAT_I(inode)->i_pos = i_pos;
514 hlist_add_head(&EXFAT_I(inode)->i_hash_fat, head);
515 spin_unlock(&sbi->inode_hash_lock);
518 void exfat_unhash_inode(struct inode *inode)
520 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
522 spin_lock(&sbi->inode_hash_lock);
523 hlist_del_init(&EXFAT_I(inode)->i_hash_fat);
524 EXFAT_I(inode)->i_pos = 0;
525 spin_unlock(&sbi->inode_hash_lock);
528 struct inode *exfat_iget(struct super_block *sb, loff_t i_pos)
530 struct exfat_sb_info *sbi = EXFAT_SB(sb);
531 struct exfat_inode_info *info;
532 struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
533 struct inode *inode = NULL;
535 spin_lock(&sbi->inode_hash_lock);
536 hlist_for_each_entry(info, head, i_hash_fat) {
537 WARN_ON(info->vfs_inode.i_sb != sb);
539 if (i_pos != info->i_pos)
541 inode = igrab(&info->vfs_inode);
545 spin_unlock(&sbi->inode_hash_lock);
549 /* doesn't deal with root inode */
550 static int exfat_fill_inode(struct inode *inode, struct exfat_dir_entry *info)
552 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
553 struct exfat_inode_info *ei = EXFAT_I(inode);
554 loff_t size = info->size;
557 ei->entry = info->entry;
558 ei->attr = info->attr;
559 ei->start_clu = info->start_clu;
560 ei->flags = info->flags;
561 ei->type = info->type;
564 ei->hint_stat.eidx = 0;
565 ei->hint_stat.clu = info->start_clu;
566 ei->hint_femp.eidx = EXFAT_HINT_NONE;
567 ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
570 inode->i_uid = sbi->options.fs_uid;
571 inode->i_gid = sbi->options.fs_gid;
572 inode_inc_iversion(inode);
573 inode->i_generation = prandom_u32();
575 if (info->attr & ATTR_SUBDIR) { /* directory */
576 inode->i_generation &= ~1;
577 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
578 inode->i_op = &exfat_dir_inode_operations;
579 inode->i_fop = &exfat_dir_operations;
580 set_nlink(inode, info->num_subdirs);
581 } else { /* regular file */
582 inode->i_generation |= 1;
583 inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
584 inode->i_op = &exfat_file_inode_operations;
585 inode->i_fop = &exfat_file_operations;
586 inode->i_mapping->a_ops = &exfat_aops;
587 inode->i_mapping->nrpages = 0;
590 i_size_write(inode, size);
592 /* ondisk and aligned size should be aligned with block size */
593 if (size & (inode->i_sb->s_blocksize - 1)) {
594 size |= (inode->i_sb->s_blocksize - 1);
598 ei->i_size_aligned = size;
599 ei->i_size_ondisk = size;
601 exfat_save_attr(inode, info->attr);
603 inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >>
605 inode->i_mtime = info->mtime;
606 inode->i_ctime = info->mtime;
607 ei->i_crtime = info->crtime;
608 inode->i_atime = info->atime;
613 struct inode *exfat_build_inode(struct super_block *sb,
614 struct exfat_dir_entry *info, loff_t i_pos)
619 inode = exfat_iget(sb, i_pos);
622 inode = new_inode(sb);
624 inode = ERR_PTR(-ENOMEM);
627 inode->i_ino = iunique(sb, EXFAT_ROOT_INO);
628 inode_set_iversion(inode, 1);
629 err = exfat_fill_inode(inode, info);
632 inode = ERR_PTR(err);
635 exfat_hash_inode(inode, i_pos);
636 insert_inode_hash(inode);
641 void exfat_evict_inode(struct inode *inode)
643 truncate_inode_pages(&inode->i_data, 0);
645 if (!inode->i_nlink) {
646 i_size_write(inode, 0);
647 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
648 __exfat_truncate(inode, 0);
649 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
652 invalidate_inode_buffers(inode);
654 exfat_cache_inval_inode(inode);
655 exfat_unhash_inode(inode);