1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * NILFS inode operations.
4 *
5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6 *
7 * Written by Ryusuke Konishi.
8 *
9 */
10
11 #include <linux/buffer_head.h>
12 #include <linux/gfp.h>
13 #include <linux/mpage.h>
14 #include <linux/pagemap.h>
15 #include <linux/writeback.h>
16 #include <linux/uio.h>
17 #include <linux/fiemap.h>
18 #include "nilfs.h"
19 #include "btnode.h"
20 #include "segment.h"
21 #include "page.h"
22 #include "mdt.h"
23 #include "cpfile.h"
24 #include "ifile.h"
25
26 /**
27 * struct nilfs_iget_args - arguments used during comparison between inodes
28 * @ino: inode number
29 * @cno: checkpoint number
30 * @root: pointer on NILFS root object (mounted checkpoint)
31 * @for_gc: inode for GC flag
32 * @for_btnc: inode for B-tree node cache flag
33 * @for_shadow: inode for shadowed page cache flag
34 */
35 struct nilfs_iget_args {
36 u64 ino;
37 __u64 cno;
38 struct nilfs_root *root;
39 bool for_gc;
40 bool for_btnc;
41 bool for_shadow;
42 };
43
44 static int nilfs_iget_test(struct inode *inode, void *opaque);
45
46 void nilfs_inode_add_blocks(struct inode *inode, int n)
47 {
48 struct nilfs_root *root = NILFS_I(inode)->i_root;
49
50 inode_add_bytes(inode, i_blocksize(inode) * n);
51 if (root)
52 atomic64_add(n, &root->blocks_count);
53 }
54
55 void nilfs_inode_sub_blocks(struct inode *inode, int n)
56 {
57 struct nilfs_root *root = NILFS_I(inode)->i_root;
58
59 inode_sub_bytes(inode, i_blocksize(inode) * n);
60 if (root)
61 atomic64_sub(n, &root->blocks_count);
62 }
63
64 /**
65 * nilfs_get_block() - get a file block on the filesystem (callback function)
66 * @inode: inode struct of the target file
67 * @blkoff: file block number
68 * @bh_result: buffer head to be mapped on
69 * @create: indicate whether allocating the block or not when it has not
70 * been allocated yet.
71 *
72 * This function does not issue actual read request of the specified data
73 * block. It is done by VFS.
74 */
75 int nilfs_get_block(struct inode *inode, sector_t blkoff,
76 struct buffer_head *bh_result, int create)
77 {
78 struct nilfs_inode_info *ii = NILFS_I(inode);
79 struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
80 __u64 blknum = 0;
81 int err = 0, ret;
82 unsigned int maxblocks = bh_result->b_size >> inode->i_blkbits;
83
84 down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
85 ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
86 up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
87 if (ret >= 0) { /* found */
88 map_bh(bh_result, inode->i_sb, blknum);
89 if (ret > 0)
90 bh_result->b_size = (ret << inode->i_blkbits);
91 goto out;
92 }
93 /* data block was not found */
94 if (ret == -ENOENT && create) {
95 struct nilfs_transaction_info ti;
96
97 bh_result->b_blocknr = 0;
98 err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
99 if (unlikely(err))
100 goto out;
101 err = nilfs_bmap_insert(ii->i_bmap, blkoff,
102 (unsigned long)bh_result);
103 if (unlikely(err != 0)) {
104 if (err == -EEXIST) {
105 /*
106 * The get_block() function could be called
107 * from multiple callers for an inode.
108 * However, the page having this block must
109 * be locked in this case.
110 */
111 nilfs_warn(inode->i_sb,
112 "%s (ino=%lu): a race condition while inserting a data block at offset=%llu",
113 __func__, inode->i_ino,
114 (unsigned long long)blkoff);
115 err = -EAGAIN;
116 }
117 nilfs_transaction_abort(inode->i_sb);
118 goto out;
119 }
120 nilfs_mark_inode_dirty_sync(inode);
121 nilfs_transaction_commit(inode->i_sb); /* never fails */
122 /* Error handling should be detailed */
123 set_buffer_new(bh_result);
124 set_buffer_delay(bh_result);
125 map_bh(bh_result, inode->i_sb, 0);
126 /* Disk block number must be changed to proper value */
127
128 } else if (ret == -ENOENT) {
129 /*
130 * not found is not error (e.g. hole); must return without
131 * the mapped state flag.
132 */
133 ;
134 } else {
135 err = ret;
136 }
137
138 out:
139 return err;
140 }
141
142 /**
143 * nilfs_read_folio() - implement read_folio() method of nilfs_aops {}
144 * address_space_operations.
145 * @file: file struct of the file to be read
146 * @folio: the folio to be read
147 */
148 static int nilfs_read_folio(struct file *file, struct folio *folio)
149 {
150 return mpage_read_folio(folio, nilfs_get_block);
151 }
152
153 static void nilfs_readahead(struct readahead_control *rac)
154 {
155 mpage_readahead(rac, nilfs_get_block);
156 }
157
158 static int nilfs_writepages(struct address_space *mapping,
159 struct writeback_control *wbc)
160 {
161 struct inode *inode = mapping->host;
162 int err = 0;
163
164 if (sb_rdonly(inode->i_sb)) {
165 nilfs_clear_dirty_pages(mapping, false);
166 return -EROFS;
167 }
168
169 if (wbc->sync_mode == WB_SYNC_ALL)
170 err = nilfs_construct_dsync_segment(inode->i_sb, inode,
171 wbc->range_start,
172 wbc->range_end);
173 return err;
174 }
175
176 static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
177 {
178 struct folio *folio = page_folio(page);
179 struct inode *inode = folio->mapping->host;
180 int err;
181
182 if (sb_rdonly(inode->i_sb)) {
183 /*
184 * It means that filesystem was remounted in read-only
185 * mode because of error or metadata corruption. But we
186 * have dirty pages that try to be flushed in background.
187 * So, here we simply discard this dirty page.
188 */
189 nilfs_clear_folio_dirty(folio, false);
190 folio_unlock(folio);
191 return -EROFS;
192 }
193
194 folio_redirty_for_writepage(wbc, folio);
195 folio_unlock(folio);
196
197 if (wbc->sync_mode == WB_SYNC_ALL) {
198 err = nilfs_construct_segment(inode->i_sb);
199 if (unlikely(err))
200 return err;
201 } else if (wbc->for_reclaim)
202 nilfs_flush_segment(inode->i_sb, inode->i_ino);
203
204 return 0;
205 }
206
207 static bool nilfs_dirty_folio(struct address_space *mapping,
208 struct folio *folio)
209 {
210 struct inode *inode = mapping->host;
211 struct buffer_head *head;
212 unsigned int nr_dirty = 0;
213 bool ret = filemap_dirty_folio(mapping, folio);
214
215 /*
216 * The page may not be locked, eg if called from try_to_unmap_one()
217 */
218 spin_lock(&mapping->i_private_lock);
219 head = folio_buffers(folio);
220 if (head) {
221 struct buffer_head *bh = head;
222
223 do {
224 /* Do not mark hole blocks dirty */
225 if (buffer_dirty(bh) || !buffer_mapped(bh))
226 continue;
227
228 set_buffer_dirty(bh);
229 nr_dirty++;
230 } while (bh = bh->b_this_page, bh != head);
231 } else if (ret) {
232 nr_dirty = 1 << (folio_shift(folio) - inode->i_blkbits);
233 }
234 spin_unlock(&mapping->i_private_lock);
235
236 if (nr_dirty)
237 nilfs_set_file_dirty(inode, nr_dirty);
238 return ret;
239 }
240
241 void nilfs_write_failed(struct address_space *mapping, loff_t to)
242 {
243 struct inode *inode = mapping->host;
244
245 if (to > inode->i_size) {
246 truncate_pagecache(inode, inode->i_size);
247 nilfs_truncate(inode);
248 }
249 }
250
251 static int nilfs_write_begin(struct file *file, struct address_space *mapping,
252 loff_t pos, unsigned len,
253 struct page **pagep, void **fsdata)
254
255 {
256 struct inode *inode = mapping->host;
257 int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
258
259 if (unlikely(err))
260 return err;
261
262 err = block_write_begin(mapping, pos, len, pagep, nilfs_get_block);
263 if (unlikely(err)) {
264 nilfs_write_failed(mapping, pos + len);
265 nilfs_transaction_abort(inode->i_sb);
266 }
267 return err;
268 }
269
270 static int nilfs_write_end(struct file *file, struct address_space *mapping,
271 loff_t pos, unsigned len, unsigned copied,
272 struct page *page, void *fsdata)
273 {
274 struct inode *inode = mapping->host;
275 unsigned int start = pos & (PAGE_SIZE - 1);
276 unsigned int nr_dirty;
277 int err;
278
279 nr_dirty = nilfs_page_count_clean_buffers(page, start,
280 start + copied);
281 copied = generic_write_end(file, mapping, pos, len, copied, page,
282 fsdata);
283 nilfs_set_file_dirty(inode, nr_dirty);
284 err = nilfs_transaction_commit(inode->i_sb);
285 return err ? : copied;
286 }
287
288 static ssize_t
289 nilfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
290 {
291 struct inode *inode = file_inode(iocb->ki_filp);
292
293 if (iov_iter_rw(iter) == WRITE)
294 return 0;
295
296 /* Needs synchronization with the cleaner */
297 return blockdev_direct_IO(iocb, inode, iter, nilfs_get_block);
298 }
299
300 const struct address_space_operations nilfs_aops = {
301 .writepage = nilfs_writepage,
302 .read_folio = nilfs_read_folio,
303 .writepages = nilfs_writepages,
304 .dirty_folio = nilfs_dirty_folio,
305 .readahead = nilfs_readahead,
306 .write_begin = nilfs_write_begin,
307 .write_end = nilfs_write_end,
308 .invalidate_folio = block_invalidate_folio,
309 .direct_IO = nilfs_direct_IO,
310 .is_partially_uptodate = block_is_partially_uptodate,
311 };
312
313 static int nilfs_insert_inode_locked(struct inode *inode,
314 struct nilfs_root *root,
315 unsigned long ino)
316 {
317 struct nilfs_iget_args args = {
318 .ino = ino, .root = root, .cno = 0, .for_gc = false,
319 .for_btnc = false, .for_shadow = false
320 };
321
322 return insert_inode_locked4(inode, ino, nilfs_iget_test, &args);
323 }
324
325 struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
326 {
327 struct super_block *sb = dir->i_sb;
328 struct the_nilfs *nilfs = sb->s_fs_info;
329 struct inode *inode;
330 struct nilfs_inode_info *ii;
331 struct nilfs_root *root;
332 struct buffer_head *bh;
333 int err = -ENOMEM;
334 ino_t ino;
335
336 inode = new_inode(sb);
337 if (unlikely(!inode))
338 goto failed;
339
340 mapping_set_gfp_mask(inode->i_mapping,
341 mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
342
343 root = NILFS_I(dir)->i_root;
344 ii = NILFS_I(inode);
345 ii->i_state = BIT(NILFS_I_NEW);
346 ii->i_root = root;
347
348 err = nilfs_ifile_create_inode(root->ifile, &ino, &bh);
349 if (unlikely(err))
350 goto failed_ifile_create_inode;
351 /* reference count of i_bh inherits from nilfs_mdt_read_block() */
352
353 if (unlikely(ino < NILFS_USER_INO)) {
354 nilfs_warn(sb,
355 "inode bitmap is inconsistent for reserved inodes");
356 do {
357 brelse(bh);
358 err = nilfs_ifile_create_inode(root->ifile, &ino, &bh);
359 if (unlikely(err))
360 goto failed_ifile_create_inode;
361 } while (ino < NILFS_USER_INO);
362
363 nilfs_info(sb, "repaired inode bitmap for reserved inodes");
364 }
365 ii->i_bh = bh;
366
367 atomic64_inc(&root->inodes_count);
368 inode_init_owner(&nop_mnt_idmap, inode, dir, mode);
369 inode->i_ino = ino;
370 simple_inode_init_ts(inode);
371
372 if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
373 err = nilfs_bmap_read(ii->i_bmap, NULL);
374 if (err < 0)
375 goto failed_after_creation;
376
377 set_bit(NILFS_I_BMAP, &ii->i_state);
378 /* No lock is needed; iget() ensures it. */
379 }
380
381 ii->i_flags = nilfs_mask_flags(
382 mode, NILFS_I(dir)->i_flags & NILFS_FL_INHERITED);
383
384 /* ii->i_file_acl = 0; */
385 /* ii->i_dir_acl = 0; */
386 ii->i_dir_start_lookup = 0;
387 nilfs_set_inode_flags(inode);
388 spin_lock(&nilfs->ns_next_gen_lock);
389 inode->i_generation = nilfs->ns_next_generation++;
390 spin_unlock(&nilfs->ns_next_gen_lock);
391 if (nilfs_insert_inode_locked(inode, root, ino) < 0) {
392 err = -EIO;
393 goto failed_after_creation;
394 }
395
396 err = nilfs_init_acl(inode, dir);
397 if (unlikely(err))
398 /*
399 * Never occur. When supporting nilfs_init_acl(),
400 * proper cancellation of above jobs should be considered.
401 */
402 goto failed_after_creation;
403
404 return inode;
405
406 failed_after_creation:
407 clear_nlink(inode);
408 if (inode->i_state & I_NEW)
409 unlock_new_inode(inode);
410 iput(inode); /*
411 * raw_inode will be deleted through
412 * nilfs_evict_inode().
413 */
414 goto failed;
415
416 failed_ifile_create_inode:
417 make_bad_inode(inode);
418 iput(inode);
419 failed:
420 return ERR_PTR(err);
421 }
422
423 void nilfs_set_inode_flags(struct inode *inode)
424 {
425 unsigned int flags = NILFS_I(inode)->i_flags;
426 unsigned int new_fl = 0;
427
428 if (flags & FS_SYNC_FL)
429 new_fl |= S_SYNC;
430 if (flags & FS_APPEND_FL)
431 new_fl |= S_APPEND;
432 if (flags & FS_IMMUTABLE_FL)
433 new_fl |= S_IMMUTABLE;
434 if (flags & FS_NOATIME_FL)
435 new_fl |= S_NOATIME;
436 if (flags & FS_DIRSYNC_FL)
437 new_fl |= S_DIRSYNC;
438 inode_set_flags(inode, new_fl, S_SYNC | S_APPEND | S_IMMUTABLE |
439 S_NOATIME | S_DIRSYNC);
440 }
441
442 int nilfs_read_inode_common(struct inode *inode,
443 struct nilfs_inode *raw_inode)
444 {
445 struct nilfs_inode_info *ii = NILFS_I(inode);
446 int err;
447
448 inode->i_mode = le16_to_cpu(raw_inode->i_mode);
449 i_uid_write(inode, le32_to_cpu(raw_inode->i_uid));
450 i_gid_write(inode, le32_to_cpu(raw_inode->i_gid));
451 set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
452 inode->i_size = le64_to_cpu(raw_inode->i_size);
453 inode_set_atime(inode, le64_to_cpu(raw_inode->i_mtime),
454 le32_to_cpu(raw_inode->i_mtime_nsec));
455 inode_set_ctime(inode, le64_to_cpu(raw_inode->i_ctime),
456 le32_to_cpu(raw_inode->i_ctime_nsec));
457 inode_set_mtime(inode, le64_to_cpu(raw_inode->i_mtime),
458 le32_to_cpu(raw_inode->i_mtime_nsec));
459 if (nilfs_is_metadata_file_inode(inode) && !S_ISREG(inode->i_mode))
460 return -EIO; /* this inode is for metadata and corrupted */
461 if (inode->i_nlink == 0)
462 return -ESTALE; /* this inode is deleted */
463
464 inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
465 ii->i_flags = le32_to_cpu(raw_inode->i_flags);
466 #if 0
467 ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
468 ii->i_dir_acl = S_ISREG(inode->i_mode) ?
469 0 : le32_to_cpu(raw_inode->i_dir_acl);
470 #endif
471 ii->i_dir_start_lookup = 0;
472 inode->i_generation = le32_to_cpu(raw_inode->i_generation);
473
474 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
475 S_ISLNK(inode->i_mode)) {
476 err = nilfs_bmap_read(ii->i_bmap, raw_inode);
477 if (err < 0)
478 return err;
479 set_bit(NILFS_I_BMAP, &ii->i_state);
480 /* No lock is needed; iget() ensures it. */
481 }
482 return 0;
483 }
484
485 static int __nilfs_read_inode(struct super_block *sb,
486 struct nilfs_root *root, unsigned long ino,
487 struct inode *inode)
488 {
489 struct the_nilfs *nilfs = sb->s_fs_info;
490 struct buffer_head *bh;
491 struct nilfs_inode *raw_inode;
492 int err;
493
494 down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
495 err = nilfs_ifile_get_inode_block(root->ifile, ino, &bh);
496 if (unlikely(err))
497 goto bad_inode;
498
499 raw_inode = nilfs_ifile_map_inode(root->ifile, ino, bh);
500
501 err = nilfs_read_inode_common(inode, raw_inode);
502 if (err)
503 goto failed_unmap;
504
505 if (S_ISREG(inode->i_mode)) {
506 inode->i_op = &nilfs_file_inode_operations;
507 inode->i_fop = &nilfs_file_operations;
508 inode->i_mapping->a_ops = &nilfs_aops;
509 } else if (S_ISDIR(inode->i_mode)) {
510 inode->i_op = &nilfs_dir_inode_operations;
511 inode->i_fop = &nilfs_dir_operations;
512 inode->i_mapping->a_ops = &nilfs_aops;
513 } else if (S_ISLNK(inode->i_mode)) {
514 inode->i_op = &nilfs_symlink_inode_operations;
515 inode_nohighmem(inode);
516 inode->i_mapping->a_ops = &nilfs_aops;
517 } else {
518 inode->i_op = &nilfs_special_inode_operations;
519 init_special_inode(
520 inode, inode->i_mode,
521 huge_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
522 }
523 nilfs_ifile_unmap_inode(raw_inode);
524 brelse(bh);
525 up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
526 nilfs_set_inode_flags(inode);
527 mapping_set_gfp_mask(inode->i_mapping,
528 mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
529 return 0;
530
531 failed_unmap:
532 nilfs_ifile_unmap_inode(raw_inode);
533 brelse(bh);
534
535 bad_inode:
536 up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
537 return err;
538 }
539
540 static int nilfs_iget_test(struct inode *inode, void *opaque)
541 {
542 struct nilfs_iget_args *args = opaque;
543 struct nilfs_inode_info *ii;
544
545 if (args->ino != inode->i_ino || args->root != NILFS_I(inode)->i_root)
546 return 0;
547
548 ii = NILFS_I(inode);
549 if (test_bit(NILFS_I_BTNC, &ii->i_state)) {
550 if (!args->for_btnc)
551 return 0;
552 } else if (args->for_btnc) {
553 return 0;
554 }
555 if (test_bit(NILFS_I_SHADOW, &ii->i_state)) {
556 if (!args->for_shadow)
557 return 0;
558 } else if (args->for_shadow) {
559 return 0;
560 }
561
562 if (!test_bit(NILFS_I_GCINODE, &ii->i_state))
563 return !args->for_gc;
564
565 return args->for_gc && args->cno == ii->i_cno;
566 }
567
568 static int nilfs_iget_set(struct inode *inode, void *opaque)
569 {
570 struct nilfs_iget_args *args = opaque;
571
572 inode->i_ino = args->ino;
573 NILFS_I(inode)->i_cno = args->cno;
574 NILFS_I(inode)->i_root = args->root;
575 if (args->root && args->ino == NILFS_ROOT_INO)
576 nilfs_get_root(args->root);
577
578 if (args->for_gc)
579 NILFS_I(inode)->i_state = BIT(NILFS_I_GCINODE);
580 if (args->for_btnc)
581 NILFS_I(inode)->i_state |= BIT(NILFS_I_BTNC);
582 if (args->for_shadow)
583 NILFS_I(inode)->i_state |= BIT(NILFS_I_SHADOW);
584 return 0;
585 }
586
587 struct inode *nilfs_ilookup(struct super_block *sb, struct nilfs_root *root,
588 unsigned long ino)
589 {
590 struct nilfs_iget_args args = {
591 .ino = ino, .root = root, .cno = 0, .for_gc = false,
592 .for_btnc = false, .for_shadow = false
593 };
594
595 return ilookup5(sb, ino, nilfs_iget_test, &args);
596 }
597
598 struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
599 unsigned long ino)
600 {
601 struct nilfs_iget_args args = {
602 .ino = ino, .root = root, .cno = 0, .for_gc = false,
603 .for_btnc = false, .for_shadow = false
604 };
605
606 return iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
607 }
608
609 struct inode *nilfs_iget(struct super_block *sb, struct nilfs_root *root,
610 unsigned long ino)
611 {
612 struct inode *inode;
613 int err;
614
615 inode = nilfs_iget_locked(sb, root, ino);
616 if (unlikely(!inode))
617 return ERR_PTR(-ENOMEM);
618 if (!(inode->i_state & I_NEW))
619 return inode;
620
621 err = __nilfs_read_inode(sb, root, ino, inode);
622 if (unlikely(err)) {
623 iget_failed(inode);
624 return ERR_PTR(err);
625 }
626 unlock_new_inode(inode);
627 return inode;
628 }
629
630 struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
631 __u64 cno)
632 {
633 struct nilfs_iget_args args = {
634 .ino = ino, .root = NULL, .cno = cno, .for_gc = true,
635 .for_btnc = false, .for_shadow = false
636 };
637 struct inode *inode;
638 int err;
639
640 inode = iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
641 if (unlikely(!inode))
642 return ERR_PTR(-ENOMEM);
643 if (!(inode->i_state & I_NEW))
644 return inode;
645
646 err = nilfs_init_gcinode(inode);
647 if (unlikely(err)) {
648 iget_failed(inode);
649 return ERR_PTR(err);
650 }
651 unlock_new_inode(inode);
652 return inode;
653 }
654
655 /**
656 * nilfs_attach_btree_node_cache - attach a B-tree node cache to the inode
657 * @inode: inode object
658 *
659 * nilfs_attach_btree_node_cache() attaches a B-tree node cache to @inode,
660 * or does nothing if the inode already has it. This function allocates
661 * an additional inode to maintain page cache of B-tree nodes one-on-one.
662 *
663 * Return Value: On success, 0 is returned. On errors, one of the following
664 * negative error code is returned.
665 *
666 * %-ENOMEM - Insufficient memory available.
667 */
668 int nilfs_attach_btree_node_cache(struct inode *inode)
669 {
670 struct nilfs_inode_info *ii = NILFS_I(inode);
671 struct inode *btnc_inode;
672 struct nilfs_iget_args args;
673
674 if (ii->i_assoc_inode)
675 return 0;
676
677 args.ino = inode->i_ino;
678 args.root = ii->i_root;
679 args.cno = ii->i_cno;
680 args.for_gc = test_bit(NILFS_I_GCINODE, &ii->i_state) != 0;
681 args.for_btnc = true;
682 args.for_shadow = test_bit(NILFS_I_SHADOW, &ii->i_state) != 0;
683
684 btnc_inode = iget5_locked(inode->i_sb, inode->i_ino, nilfs_iget_test,
685 nilfs_iget_set, &args);
686 if (unlikely(!btnc_inode))
687 return -ENOMEM;
688 if (btnc_inode->i_state & I_NEW) {
689 nilfs_init_btnc_inode(btnc_inode);
690 unlock_new_inode(btnc_inode);
691 }
692 NILFS_I(btnc_inode)->i_assoc_inode = inode;
693 NILFS_I(btnc_inode)->i_bmap = ii->i_bmap;
694 ii->i_assoc_inode = btnc_inode;
695
696 return 0;
697 }
698
699 /**
700 * nilfs_detach_btree_node_cache - detach the B-tree node cache from the inode
701 * @inode: inode object
702 *
703 * nilfs_detach_btree_node_cache() detaches the B-tree node cache and its
704 * holder inode bound to @inode, or does nothing if @inode doesn't have it.
705 */
706 void nilfs_detach_btree_node_cache(struct inode *inode)
707 {
708 struct nilfs_inode_info *ii = NILFS_I(inode);
709 struct inode *btnc_inode = ii->i_assoc_inode;
710
711 if (btnc_inode) {
712 NILFS_I(btnc_inode)->i_assoc_inode = NULL;
713 ii->i_assoc_inode = NULL;
714 iput(btnc_inode);
715 }
716 }
717
718 /**
719 * nilfs_iget_for_shadow - obtain inode for shadow mapping
720 * @inode: inode object that uses shadow mapping
721 *
722 * nilfs_iget_for_shadow() allocates a pair of inodes that holds page
723 * caches for shadow mapping. The page cache for data pages is set up
724 * in one inode and the one for b-tree node pages is set up in the
725 * other inode, which is attached to the former inode.
726 *
727 * Return Value: On success, a pointer to the inode for data pages is
728 * returned. On errors, one of the following negative error code is returned
729 * in a pointer type.
730 *
731 * %-ENOMEM - Insufficient memory available.
732 */
733 struct inode *nilfs_iget_for_shadow(struct inode *inode)
734 {
735 struct nilfs_iget_args args = {
736 .ino = inode->i_ino, .root = NULL, .cno = 0, .for_gc = false,
737 .for_btnc = false, .for_shadow = true
738 };
739 struct inode *s_inode;
740 int err;
741
742 s_inode = iget5_locked(inode->i_sb, inode->i_ino, nilfs_iget_test,
743 nilfs_iget_set, &args);
744 if (unlikely(!s_inode))
745 return ERR_PTR(-ENOMEM);
746 if (!(s_inode->i_state & I_NEW))
747 return inode;
748
749 NILFS_I(s_inode)->i_flags = 0;
750 memset(NILFS_I(s_inode)->i_bmap, 0, sizeof(struct nilfs_bmap));
751 mapping_set_gfp_mask(s_inode->i_mapping, GFP_NOFS);
752
753 err = nilfs_attach_btree_node_cache(s_inode);
754 if (unlikely(err)) {
755 iget_failed(s_inode);
756 return ERR_PTR(err);
757 }
758 unlock_new_inode(s_inode);
759 return s_inode;
760 }
761
762 /**
763 * nilfs_write_inode_common - export common inode information to on-disk inode
764 * @inode: inode object
765 * @raw_inode: on-disk inode
766 *
767 * This function writes standard information from the on-memory inode @inode
768 * to @raw_inode on ifile, cpfile or a super root block. Since inode bmap
769 * data is not exported, nilfs_bmap_write() must be called separately during
770 * log writing.
771 */
772 void nilfs_write_inode_common(struct inode *inode,
773 struct nilfs_inode *raw_inode)
774 {
775 struct nilfs_inode_info *ii = NILFS_I(inode);
776
777 raw_inode->i_mode = cpu_to_le16(inode->i_mode);
778 raw_inode->i_uid = cpu_to_le32(i_uid_read(inode));
779 raw_inode->i_gid = cpu_to_le32(i_gid_read(inode));
780 raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
781 raw_inode->i_size = cpu_to_le64(inode->i_size);
782 raw_inode->i_ctime = cpu_to_le64(inode_get_ctime_sec(inode));
783 raw_inode->i_mtime = cpu_to_le64(inode_get_mtime_sec(inode));
784 raw_inode->i_ctime_nsec = cpu_to_le32(inode_get_ctime_nsec(inode));
785 raw_inode->i_mtime_nsec = cpu_to_le32(inode_get_mtime_nsec(inode));
786 raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
787
788 raw_inode->i_flags = cpu_to_le32(ii->i_flags);
789 raw_inode->i_generation = cpu_to_le32(inode->i_generation);
790
791 /*
792 * When extending inode, nilfs->ns_inode_size should be checked
793 * for substitutions of appended fields.
794 */
795 }
796
797 void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh, int flags)
798 {
799 ino_t ino = inode->i_ino;
800 struct nilfs_inode_info *ii = NILFS_I(inode);
801 struct inode *ifile = ii->i_root->ifile;
802 struct nilfs_inode *raw_inode;
803
804 raw_inode = nilfs_ifile_map_inode(ifile, ino, ibh);
805
806 if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
807 memset(raw_inode, 0, NILFS_MDT(ifile)->mi_entry_size);
808 if (flags & I_DIRTY_DATASYNC)
809 set_bit(NILFS_I_INODE_SYNC, &ii->i_state);
810
811 nilfs_write_inode_common(inode, raw_inode);
812
813 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
814 raw_inode->i_device_code =
815 cpu_to_le64(huge_encode_dev(inode->i_rdev));
816
817 nilfs_ifile_unmap_inode(raw_inode);
818 }
819
820 #define NILFS_MAX_TRUNCATE_BLOCKS 16384 /* 64MB for 4KB block */
821
822 static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
823 unsigned long from)
824 {
825 __u64 b;
826 int ret;
827
828 if (!test_bit(NILFS_I_BMAP, &ii->i_state))
829 return;
830 repeat:
831 ret = nilfs_bmap_last_key(ii->i_bmap, &b);
832 if (ret == -ENOENT)
833 return;
834 else if (ret < 0)
835 goto failed;
836
837 if (b < from)
838 return;
839
840 b -= min_t(__u64, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
841 ret = nilfs_bmap_truncate(ii->i_bmap, b);
842 nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
843 if (!ret || (ret == -ENOMEM &&
844 nilfs_bmap_truncate(ii->i_bmap, b) == 0))
845 goto repeat;
846
847 failed:
848 nilfs_warn(ii->vfs_inode.i_sb, "error %d truncating bmap (ino=%lu)",
849 ret, ii->vfs_inode.i_ino);
850 }
851
852 void nilfs_truncate(struct inode *inode)
853 {
854 unsigned long blkoff;
855 unsigned int blocksize;
856 struct nilfs_transaction_info ti;
857 struct super_block *sb = inode->i_sb;
858 struct nilfs_inode_info *ii = NILFS_I(inode);
859
860 if (!test_bit(NILFS_I_BMAP, &ii->i_state))
861 return;
862 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
863 return;
864
865 blocksize = sb->s_blocksize;
866 blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
867 nilfs_transaction_begin(sb, &ti, 0); /* never fails */
868
869 block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
870
871 nilfs_truncate_bmap(ii, blkoff);
872
873 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
874 if (IS_SYNC(inode))
875 nilfs_set_transaction_flag(NILFS_TI_SYNC);
876
877 nilfs_mark_inode_dirty(inode);
878 nilfs_set_file_dirty(inode, 0);
879 nilfs_transaction_commit(sb);
880 /*
881 * May construct a logical segment and may fail in sync mode.
882 * But truncate has no return value.
883 */
884 }
885
886 static void nilfs_clear_inode(struct inode *inode)
887 {
888 struct nilfs_inode_info *ii = NILFS_I(inode);
889
890 /*
891 * Free resources allocated in nilfs_read_inode(), here.
892 */
893 BUG_ON(!list_empty(&ii->i_dirty));
894 brelse(ii->i_bh);
895 ii->i_bh = NULL;
896
897 if (nilfs_is_metadata_file_inode(inode))
898 nilfs_mdt_clear(inode);
899
900 if (test_bit(NILFS_I_BMAP, &ii->i_state))
901 nilfs_bmap_clear(ii->i_bmap);
902
903 if (!test_bit(NILFS_I_BTNC, &ii->i_state))
904 nilfs_detach_btree_node_cache(inode);
905
906 if (ii->i_root && inode->i_ino == NILFS_ROOT_INO)
907 nilfs_put_root(ii->i_root);
908 }
909
910 void nilfs_evict_inode(struct inode *inode)
911 {
912 struct nilfs_transaction_info ti;
913 struct super_block *sb = inode->i_sb;
914 struct nilfs_inode_info *ii = NILFS_I(inode);
915 struct the_nilfs *nilfs;
916 int ret;
917
918 if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
919 truncate_inode_pages_final(&inode->i_data);
920 clear_inode(inode);
921 nilfs_clear_inode(inode);
922 return;
923 }
924 nilfs_transaction_begin(sb, &ti, 0); /* never fails */
925
926 truncate_inode_pages_final(&inode->i_data);
927
928 nilfs = sb->s_fs_info;
929 if (unlikely(sb_rdonly(sb) || !nilfs->ns_writer)) {
930 /*
931 * If this inode is about to be disposed after the file system
932 * has been degraded to read-only due to file system corruption
933 * or after the writer has been detached, do not make any
934 * changes that cause writes, just clear it.
935 * Do this check after read-locking ns_segctor_sem by
936 * nilfs_transaction_begin() in order to avoid a race with
937 * the writer detach operation.
938 */
939 clear_inode(inode);
940 nilfs_clear_inode(inode);
941 nilfs_transaction_abort(sb);
942 return;
943 }
944
945 /* TODO: some of the following operations may fail. */
946 nilfs_truncate_bmap(ii, 0);
947 nilfs_mark_inode_dirty(inode);
948 clear_inode(inode);
949
950 ret = nilfs_ifile_delete_inode(ii->i_root->ifile, inode->i_ino);
951 if (!ret)
952 atomic64_dec(&ii->i_root->inodes_count);
953
954 nilfs_clear_inode(inode);
955
956 if (IS_SYNC(inode))
957 nilfs_set_transaction_flag(NILFS_TI_SYNC);
958 nilfs_transaction_commit(sb);
959 /*
960 * May construct a logical segment and may fail in sync mode.
961 * But delete_inode has no return value.
962 */
963 }
964
965 int nilfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
966 struct iattr *iattr)
967 {
968 struct nilfs_transaction_info ti;
969 struct inode *inode = d_inode(dentry);
970 struct super_block *sb = inode->i_sb;
971 int err;
972
973 err = setattr_prepare(&nop_mnt_idmap, dentry, iattr);
974 if (err)
975 return err;
976
977 err = nilfs_transaction_begin(sb, &ti, 0);
978 if (unlikely(err))
979 return err;
980
981 if ((iattr->ia_valid & ATTR_SIZE) &&
982 iattr->ia_size != i_size_read(inode)) {
983 inode_dio_wait(inode);
984 truncate_setsize(inode, iattr->ia_size);
985 nilfs_truncate(inode);
986 }
987
988 setattr_copy(&nop_mnt_idmap, inode, iattr);
989 mark_inode_dirty(inode);
990
991 if (iattr->ia_valid & ATTR_MODE) {
992 err = nilfs_acl_chmod(inode);
993 if (unlikely(err))
994 goto out_err;
995 }
996
997 return nilfs_transaction_commit(sb);
998
999 out_err:
1000 nilfs_transaction_abort(sb);
1001 return err;
1002 }
1003
1004 int nilfs_permission(struct mnt_idmap *idmap, struct inode *inode,
1005 int mask)
1006 {
1007 struct nilfs_root *root = NILFS_I(inode)->i_root;
1008
1009 if ((mask & MAY_WRITE) && root &&
1010 root->cno != NILFS_CPTREE_CURRENT_CNO)
1011 return -EROFS; /* snapshot is not writable */
1012
1013 return generic_permission(&nop_mnt_idmap, inode, mask);
1014 }
1015
1016 int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
1017 {
1018 struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1019 struct nilfs_inode_info *ii = NILFS_I(inode);
1020 int err;
1021
1022 spin_lock(&nilfs->ns_inode_lock);
1023 if (ii->i_bh == NULL || unlikely(!buffer_uptodate(ii->i_bh))) {
1024 spin_unlock(&nilfs->ns_inode_lock);
1025 err = nilfs_ifile_get_inode_block(ii->i_root->ifile,
1026 inode->i_ino, pbh);
1027 if (unlikely(err))
1028 return err;
1029 spin_lock(&nilfs->ns_inode_lock);
1030 if (ii->i_bh == NULL)
1031 ii->i_bh = *pbh;
1032 else if (unlikely(!buffer_uptodate(ii->i_bh))) {
1033 __brelse(ii->i_bh);
1034 ii->i_bh = *pbh;
1035 } else {
1036 brelse(*pbh);
1037 *pbh = ii->i_bh;
1038 }
1039 } else
1040 *pbh = ii->i_bh;
1041
1042 get_bh(*pbh);
1043 spin_unlock(&nilfs->ns_inode_lock);
1044 return 0;
1045 }
1046
1047 int nilfs_inode_dirty(struct inode *inode)
1048 {
1049 struct nilfs_inode_info *ii = NILFS_I(inode);
1050 struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1051 int ret = 0;
1052
1053 if (!list_empty(&ii->i_dirty)) {
1054 spin_lock(&nilfs->ns_inode_lock);
1055 ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
1056 test_bit(NILFS_I_BUSY, &ii->i_state);
1057 spin_unlock(&nilfs->ns_inode_lock);
1058 }
1059 return ret;
1060 }
1061
1062 int nilfs_set_file_dirty(struct inode *inode, unsigned int nr_dirty)
1063 {
1064 struct nilfs_inode_info *ii = NILFS_I(inode);
1065 struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1066
1067 atomic_add(nr_dirty, &nilfs->ns_ndirtyblks);
1068
1069 if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
1070 return 0;
1071
1072 spin_lock(&nilfs->ns_inode_lock);
1073 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
1074 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
1075 /*
1076 * Because this routine may race with nilfs_dispose_list(),
1077 * we have to check NILFS_I_QUEUED here, too.
1078 */
1079 if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
1080 /*
1081 * This will happen when somebody is freeing
1082 * this inode.
1083 */
1084 nilfs_warn(inode->i_sb,
1085 "cannot set file dirty (ino=%lu): the file is being freed",
1086 inode->i_ino);
1087 spin_unlock(&nilfs->ns_inode_lock);
1088 return -EINVAL; /*
1089 * NILFS_I_DIRTY may remain for
1090 * freeing inode.
1091 */
1092 }
1093 list_move_tail(&ii->i_dirty, &nilfs->ns_dirty_files);
1094 set_bit(NILFS_I_QUEUED, &ii->i_state);
1095 }
1096 spin_unlock(&nilfs->ns_inode_lock);
1097 return 0;
1098 }
1099
1100 int __nilfs_mark_inode_dirty(struct inode *inode, int flags)
1101 {
1102 struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1103 struct buffer_head *ibh;
1104 int err;
1105
1106 /*
1107 * Do not dirty inodes after the log writer has been detached
1108 * and its nilfs_root struct has been freed.
1109 */
1110 if (unlikely(nilfs_purging(nilfs)))
1111 return 0;
1112
1113 err = nilfs_load_inode_block(inode, &ibh);
1114 if (unlikely(err)) {
1115 nilfs_warn(inode->i_sb,
1116 "cannot mark inode dirty (ino=%lu): error %d loading inode block",
1117 inode->i_ino, err);
1118 return err;
1119 }
1120 nilfs_update_inode(inode, ibh, flags);
1121 mark_buffer_dirty(ibh);
1122 nilfs_mdt_mark_dirty(NILFS_I(inode)->i_root->ifile);
1123 brelse(ibh);
1124 return 0;
1125 }
1126
1127 /**
1128 * nilfs_dirty_inode - reflect changes on given inode to an inode block.
1129 * @inode: inode of the file to be registered.
1130 * @flags: flags to determine the dirty state of the inode
1131 *
1132 * nilfs_dirty_inode() loads a inode block containing the specified
1133 * @inode and copies data from a nilfs_inode to a corresponding inode
1134 * entry in the inode block. This operation is excluded from the segment
1135 * construction. This function can be called both as a single operation
1136 * and as a part of indivisible file operations.
1137 */
1138 void nilfs_dirty_inode(struct inode *inode, int flags)
1139 {
1140 struct nilfs_transaction_info ti;
1141 struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
1142
1143 if (is_bad_inode(inode)) {
1144 nilfs_warn(inode->i_sb,
1145 "tried to mark bad_inode dirty. ignored.");
1146 dump_stack();
1147 return;
1148 }
1149 if (mdi) {
1150 nilfs_mdt_mark_dirty(inode);
1151 return;
1152 }
1153 nilfs_transaction_begin(inode->i_sb, &ti, 0);
1154 __nilfs_mark_inode_dirty(inode, flags);
1155 nilfs_transaction_commit(inode->i_sb); /* never fails */
1156 }
1157
1158 int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1159 __u64 start, __u64 len)
1160 {
1161 struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1162 __u64 logical = 0, phys = 0, size = 0;
1163 __u32 flags = 0;
1164 loff_t isize;
1165 sector_t blkoff, end_blkoff;
1166 sector_t delalloc_blkoff;
1167 unsigned long delalloc_blklen;
1168 unsigned int blkbits = inode->i_blkbits;
1169 int ret, n;
1170
1171 ret = fiemap_prep(inode, fieinfo, start, &len, 0);
1172 if (ret)
1173 return ret;
1174
1175 inode_lock(inode);
1176
1177 isize = i_size_read(inode);
1178
1179 blkoff = start >> blkbits;
1180 end_blkoff = (start + len - 1) >> blkbits;
1181
1182 delalloc_blklen = nilfs_find_uncommitted_extent(inode, blkoff,
1183 &delalloc_blkoff);
1184
1185 do {
1186 __u64 blkphy;
1187 unsigned int maxblocks;
1188
1189 if (delalloc_blklen && blkoff == delalloc_blkoff) {
1190 if (size) {
1191 /* End of the current extent */
1192 ret = fiemap_fill_next_extent(
1193 fieinfo, logical, phys, size, flags);
1194 if (ret)
1195 break;
1196 }
1197 if (blkoff > end_blkoff)
1198 break;
1199
1200 flags = FIEMAP_EXTENT_MERGED | FIEMAP_EXTENT_DELALLOC;
1201 logical = blkoff << blkbits;
1202 phys = 0;
1203 size = delalloc_blklen << blkbits;
1204
1205 blkoff = delalloc_blkoff + delalloc_blklen;
1206 delalloc_blklen = nilfs_find_uncommitted_extent(
1207 inode, blkoff, &delalloc_blkoff);
1208 continue;
1209 }
1210
1211 /*
1212 * Limit the number of blocks that we look up so as
1213 * not to get into the next delayed allocation extent.
1214 */
1215 maxblocks = INT_MAX;
1216 if (delalloc_blklen)
1217 maxblocks = min_t(sector_t, delalloc_blkoff - blkoff,
1218 maxblocks);
1219 blkphy = 0;
1220
1221 down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1222 n = nilfs_bmap_lookup_contig(
1223 NILFS_I(inode)->i_bmap, blkoff, &blkphy, maxblocks);
1224 up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1225
1226 if (n < 0) {
1227 int past_eof;
1228
1229 if (unlikely(n != -ENOENT))
1230 break; /* error */
1231
1232 /* HOLE */
1233 blkoff++;
1234 past_eof = ((blkoff << blkbits) >= isize);
1235
1236 if (size) {
1237 /* End of the current extent */
1238
1239 if (past_eof)
1240 flags |= FIEMAP_EXTENT_LAST;
1241
1242 ret = fiemap_fill_next_extent(
1243 fieinfo, logical, phys, size, flags);
1244 if (ret)
1245 break;
1246 size = 0;
1247 }
1248 if (blkoff > end_blkoff || past_eof)
1249 break;
1250 } else {
1251 if (size) {
1252 if (phys && blkphy << blkbits == phys + size) {
1253 /* The current extent goes on */
1254 size += n << blkbits;
1255 } else {
1256 /* Terminate the current extent */
1257 ret = fiemap_fill_next_extent(
1258 fieinfo, logical, phys, size,
1259 flags);
1260 if (ret || blkoff > end_blkoff)
1261 break;
1262
1263 /* Start another extent */
1264 flags = FIEMAP_EXTENT_MERGED;
1265 logical = blkoff << blkbits;
1266 phys = blkphy << blkbits;
1267 size = n << blkbits;
1268 }
1269 } else {
1270 /* Start a new extent */
1271 flags = FIEMAP_EXTENT_MERGED;
1272 logical = blkoff << blkbits;
1273 phys = blkphy << blkbits;
1274 size = n << blkbits;
1275 }
1276 blkoff += n;
1277 }
1278 cond_resched();
1279 } while (true);
1280
1281 /* If ret is 1 then we just hit the end of the extent array */
1282 if (ret == 1)
1283 ret = 0;
1284
1285 inode_unlock(inode);
1286 return ret;
1287 }
1288
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